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Sample records for high glucose-treated endothelial

  1. Importance of mitochondrial calcium uniporter in high glucose-induced endothelial cell dysfunction.

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    Chen, Wei; Yang, Jie; Chen, Shuhua; Xiang, Hong; Liu, Hengdao; Lin, Dan; Zhao, Shaoli; Peng, Hui; Chen, Pan; Chen, Alex F; Lu, Hongwei

    2017-11-01

    Mitochondrial Ca 2+ overload is implicated in hyperglycaemia-induced endothelial cell dysfunction, but the key molecular events responsible remain unclear. We examined the involvement of mitochondrial calcium uniporter, which mediates mitochondrial Ca 2+ uptake, in endothelial cell dysfunction resulting from high-glucose treatment. Human umbilical vein endothelial cells were exposed to various glucose concentrations and to high glucose (30 mM) following mitochondrial calcium uniporter inhibition or activation with ruthenium red and spermine, respectively. Subsequently, mitochondrial calcium uniporter and mitochondrial calcium uniporter regulator 1 messenger RNA and protein expression was measured by real-time polymerase chain reaction and western blotting. Ca 2+ concentrations were analysed by laser confocal microscopy, and cytoplasmic and mitochondrial oxidative stress was detected using 2',7'-dichlorofluorescein diacetate and MitoSOX Red, respectively. Apoptosis was assessed by annexin V-fluorescein isothiocyanate/propidium iodide staining, and a wound-healing assay was performed using an in vitro model. High glucose markedly upregulated mitochondrial calcium uniporter and mitochondrial calcium uniporter regulator 1 messenger RNA expression, as well as protein production, in a dose- and time-dependent manner with a maximum effect demonstrated at 72 h and 30 mM glucose concentration. Moreover, high-glucose treatment significantly raised both mitochondrial and cytoplasmic Ca 2+ and reactive oxygen species levels, increased apoptosis and compromised wound healing (all p calcium uniporter, respectively. Mitochondrial calcium uniporter plays an important role in hyperglycaemia-induced endothelial cell dysfunction and may constitute a therapeutic target to reduce vascular complications in diabetes.

  2. Hydrogen Sulphide modulating mitochondrial morphology to promote mitophagy in endothelial cells under high-glucose and high-palmitate.

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    Liu, Ning; Wu, Jichao; Zhang, Linxue; Gao, Zhaopeng; Sun, Yu; Yu, Miao; Zhao, Yajun; Dong, Shiyun; Lu, Fanghao; Zhang, Weihua

    2017-12-01

    Endothelial cell dysfunction is one of the main reasons for type II diabetes vascular complications. Hydrogen sulphide (H 2 S) has antioxidative effect, but its regulation on mitochondrial dynamics and mitophagy in aortic endothelial cells under hyperglycaemia and hyperlipidaemia is unclear. Rat aortic endothelial cells (RAECs) were treated with 40 mM glucose and 200 μM palmitate to imitate endothelium under hyperglycaemia and hyperlipidaemia, and 100 μM NaHS was used as an exogenous H 2 S donor. Firstly, we demonstrated that high glucose and palmitate decreased H 2 S production and CSE expression in RAECs. Then, the antioxidative effect of H 2 S was proved in RAECs under high glucose and palmitate to reduce mitochondrial ROS level. We also showed that exogenous H 2 S inhibited mitochondrial apoptosis in RAECs under high glucose and palmitate. Using Mito Tracker and transmission electron microscopy assay, we revealed that exogenous H 2 S decreased mitochondrial fragments and significantly reduced the expression of p-Drp-1/Drp-1 and Fis1 compared to high-glucose and high-palmitate group, whereas it increased mitophagy by transmission electron microscopy assay. We demonstrated that exogenous H 2 S facilitated Parkin recruited by PINK1 by immunoprecipitation and immunostaining assays and then ubiquitylated mitofusin 2 (Mfn2), which illuminated the mechanism of exogenous H 2 S on mitophagy. Parkin siRNA suppressed the expression of Mfn2, Nix and LC3B, which revealed that it eliminated mitophagy. In summary, exogenous H 2 S could protect RAECs against apoptosis under high glucose and palmitate by suppressing oxidative stress, decreasing mitochondrial fragments and promoting mitophagy. Based on these results, we proposed a new mechanism of H 2 S on protecting endothelium, which might provide a new strategy for type II diabetes vascular complication. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for

  3. Vochysia rufa Stem Bark Extract Protects Endothelial Cells against High Glucose Damage

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    Neire Moura de Gouveia

    2017-02-01

    Full Text Available Background: Increased oxidative stress by persistent hyperglycemia is a widely accepted factor in vascular damage responsible for type 2 diabetes complications. The plant Vochysia rufa (Vr has been used in folk medicine in Brazil for the treatment of diabetes. Thus; the protective effect of a Vr stem bark extract against a challenge by a high glucose concentration on EA.hy926 (EA endothelial cells is evaluated. Methods: Vegetal material is extracted with distilled water by maceration and evaporated until dryness under vacuum. Then; it is isolated by capillary electrophoresis–tandem mass spectrometry. Cell viability is evaluated on EA cells treated with 0.5–100 µg/mL of the Vr extract for 24 h. The extract is diluted at concentrations of 5, 10 and 25 µg/mL and maintained for 24 h along with 30 mM of glucose to evaluate its protective effect on reduced glutathione (GSH; glutathione peroxidase (GPx and reductase (GR and protein carbonyl groups. Results: V. rufa stem bark is composed mainly of sugars; such as inositol; galactose; glucose; mannose; sacarose; arabinose and ribose. Treatment with Vr up to 100 µg/mL for 24 h did not affect cell viability. Treatment of EA cells with 30 mM of glucose for 24 h significantly increased the cell damage. EA cells treated with 30 mM of glucose showed a decrease of GSH concentration and increased Radical Oxygen Species (ROS and activity of antioxidant enzymes and protein carbonyl levels; compared to control. Co-treatment of EA with 30 mM glucose plus 1–10 μg/mL Vr significantly reduced cell damage while 5–25 μg/mL Vr evoked a significant protection against the glucose insult; recovering ROS; GSH; antioxidant enzymes and carbonyls to baseline levels. Conclusion: V. rufa extract protects endothelial cells against oxidative damage by modulating ROS; GSH concentration; antioxidant enzyme activity and protein carbonyl levels.

  4. Myeloperoxidase amplified high glucose-induced endothelial dysfunction in vasculature: Role of NADPH oxidase and hypochlorous acid.

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    Tian, Rong; Ding, Yun; Peng, Yi-Yuan; Lu, Naihao

    2017-03-11

    Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-derived reactive oxygen species (ROS) such as superoxide and hydrogen peroxide (H 2 O 2 ), have emerged as important molecules in the pathogenesis of diabetic endothelial dysfunction. Additionally, neutrophils-derived myeloperoxidase (MPO) and MPO-catalyzed hypochlorous acid (HOCl) play important roles in the vascular injury. However, it is unknown whether MPO can use vascular-derived ROS to induce diabetic endothelial dysfunction. In the present study, we demonstrated that NADPH oxidase was the main source of ROS formation in high glucose-cultured human umbilical vein endothelial cells (HUVECs), and played a critical role in high glucose-induced endothelial dysfunction such as cell apoptosis, loss of cell viability and reduction of nitric oxide (NO). However, the addition of MPO could amplify the high glucose-induced endothelial dysfunction which was inhibited by the presence of apocynin (NADPH oxidase inhibitor), catalase (H 2 O 2 scavenger), or methionine (HOCl scavenger), demonstrating the contribution of NADPH oxidase-H 2 O 2 -MPO-HOCl pathway in the MPO/high glucose-induced vascular injury. In high glucose-incubated rat aortas, MPO also exacerbated the NADPH oxidase-induced impairment of endothelium-dependent relaxation. Consistent with these in vitro data, in diabetic rat aortas, both MPO expresion and NADPH oxidase activity were increased while the endothelial function was simultaneously impaired. The results suggested that vascular-bound MPO could amplify high glucose-induced vascular injury in diabetes. MPO-NADPH oxidase-HOCl may represent an important pathogenic pathway in diabetic vascular diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. High glucose concentration induces endothelial cell proliferation by regulating cyclin-D2-related miR-98.

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    Li, Xin-Xin; Liu, Yue-Mei; Li, You-Jie; Xie, Ning; Yan, Yun-Fei; Chi, Yong-Liang; Zhou, Ling; Xie, Shu-Yang; Wang, Ping-Yu

    2016-06-01

    Cyclin D2 is involved in the pathology of vascular complications of type 2 diabetes mellitus (T2DM). This study investigated the role of cyclin-D2-regulated miRNAs in endothelial cell proliferation of T2DM. Results showed that higher glucose concentration (4.5 g/l) significantly promoted the proliferation of rat aortic endothelial cells (RAOECs), and significantly increased the expression of cyclin D2 and phosphorylation of retinoblastoma 1 (p-RB1) in RAOECs compared with those under low glucose concentration. The cyclin D2-3' untranslated region is targeted by miR-98, as demonstrated by miRNA analysis software. Western blot also confirmed that cyclin D2 and p-RB1 expression was regulated by miR-98. The results indicated that miR-98 treatment can induce RAOEC apoptosis. The suppression of RAOEC growth by miR-98 might be related to regulation of Bcl-2, Bax and Caspase 9 expression. Furthermore, the expression levels of miR-98 decreased in 4.5 g/l glucose-treated cells compared with those treated by low glucose concentration. Similarly, the expression of miR-98 significantly decreased in aortas of established streptozotocin (STZ)-induced diabetic rat model compared with that in control rats; but cyclin D2 and p-RB1 levels remarkably increased in aortas of STZ-induced diabetic rats compared with those in healthy control rats. In conclusion, this study demonstrated that high glucose concentration induces cyclin D2 up-regulation and miR-98 down-regulation in the RAOECs. By regulating cyclin D2, miR-98 can inhibit human endothelial cell growth, thereby providing novel therapeutic targets for vascular complication of T2DM. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  6. Effect of Buddleja officinalis on high-glucose-induced vascular inflammation in human umbilical vein endothelial cells.

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    Lee, Yun Jung; Kang, Dae Gill; Kim, Jin Sook; Lee, Ho Sub

    2008-06-01

    In this study, we aimed to investigate whether an aqueous extract of Buddleja officinalis (ABO) suppresses high-glucose-induced vascular inflammatory processes in the primary cultured human umbilical vein endothelial cells (HUVEC). The high-glucose-induced increase in expression of cell adhesion molecules (CAMs) such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial-selectin (E-selectin) was significantly attenuated by pretreatment with ABO in a dose-dependent manner. Enhanced cell adhesion caused by high glucose in co-cultured U937 and HUVEC was also blocked by pretreatment with ABO. Pretreatment with ABO also blocked formation of high-glucose-induced reactive oxygen species (ROS). In addition, ABO suppressed the transcriptional activity of NF-kappaB and IkappaB phosphorylation under high-glucose conditions. Pretreatment with N(G)-nitro-l-arginine methyl ester (L-NAME), an endothelial nitric oxide (NO) synthase inhibitor, attenuated the protective action of ABO on high-glucose-induced CAM expression, suggesting a potential role of NO signaling. The present data suggest that ABO could suppress high-glucose-induced vascular inflammatory processes, and ABO may be closely related with the inhibition of ROS and NF-kappaB activation in HUVEC.

  7. Tea polyphenols alleviate high fat and high glucose-induced endothelial hyperpermeability by attenuating ROS production via NADPH oxidase pathway.

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    Zuo, Xuezhi; Tian, Chong; Zhao, Nana; Ren, Weiye; Meng, Yi; Jin, Xin; Zhang, Ying; Ding, Shibin; Ying, Chenjiang; Ye, Xiaolei

    2014-03-02

    Hyperglycemia-induced endothelial hyperpermeability is crucial to cardiovascular disorders and macro-vascular complications in diabetes mellitus. The objective of this study is to investigate the effects of green tea polyphenols (GTPs) on endothelial hyperpermeability and the role of nicotinamide adenine dinucleotide phosphate (NADPH) pathway. Male Wistar rats fed on a high fat diet (HF) were treated with GTPs (0, 0.8, 1.6, 3.2 g/L in drinking water) for 26 weeks. Bovine aortic endothelial cells (BAECs) were treated with high glucose (HG, 33 mmol/L) and GTPs (0.0, 0.4, or 4 μg/mL) for 24 hours in vitro. The endothelial permeabilities in rat aorta and monolayer BAECs were measured by Evans blue injection method and efflux of fluorescein isothiocyanate (FITC)-dextran, respectively. The reactive oxygen species (ROS) levels in rat aorta and monolayer BAECs were measured by dihydroethidium (DHE) and 2', 7'-dichloro-fluorescein diacetate (DCFH-DA) fluorescent probe, respectively. Protein levels of NADPH oxidase subunits were determined by Western-blot. HF diet-fed increased the endothelial permeability and ROS levels in rat aorta while HG treatments increased the endothelial permeability and ROS levels in cultured BAECs. Co-treatment with GTPs alleviated those changes both in vivo and in vitro. In in vitro studies, GTPs treatments protected against the HG-induced over-expressions of p22phox and p67phox. Diphenylene iodonium chloride (DPI), an inhibitor of NADPH oxidase, alleviated the hyperpermeability induced by HG. GTPs could alleviate endothelial hyperpermeabilities in HF diet-fed rat aorta and in HG treated BAECs. The decrease of ROS production resulting from down-regulation of NADPH oxidase contributed to the alleviation of endothelial hyperpermeability.

  8. Coenzyme Q10 Attenuates High Glucose-Induced Endothelial Progenitor Cell Dysfunction through AMP-Activated Protein Kinase Pathways

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    Hsiao-Ya Tsai

    2016-01-01

    Full Text Available Coenzyme Q10 (CoQ10, an antiapoptosis enzyme, is stored in the mitochondria of cells. We investigated whether CoQ10 can attenuate high glucose-induced endothelial progenitor cell (EPC apoptosis and clarified its mechanism. EPCs were incubated with normal glucose (5 mM or high glucose (25 mM enviroment for 3 days, followed by treatment with CoQ10 (10 μM for 24 hr. Cell proliferation, nitric oxide (NO production, and JC-1 assay were examined. The specific signal pathways of AMP-activated protein kinase (AMPK, eNOS/Akt, and heme oxygenase-1 (HO-1 were also assessed. High glucose reduced EPC functional activities, including proliferation and migration. Additionally, Akt/eNOS activity and NO production were downregulated in high glucose-stimulated EPCs. Administration of CoQ10 ameliorated high glucose-induced EPC apoptosis, including downregulation of caspase 3, upregulation of Bcl-2, and increase in mitochondrial membrane potential. Furthermore, treatment with CoQ10 reduced reactive oxygen species, enhanced eNOS/Akt activity, and increased HO-1 expression in high glucose-treated EPCs. These effects were negated by administration of AMPK inhibitor. Transplantation of CoQ10-treated EPCs under high glucose conditions into ischemic hindlimbs improved blood flow recovery. CoQ10 reduced high glucose-induced EPC apoptosis and dysfunction through upregulation of eNOS, HO-1 through the AMPK pathway. Our findings provide a potential treatment strategy targeting dysfunctional EPC in diabetic patients.

  9. Coenzyme Q10 Attenuates High Glucose-Induced Endothelial Progenitor Cell Dysfunction through AMP-Activated Protein Kinase Pathways

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    Tsai, Hsiao-Ya; Lin, Chih-Pei; Huang, Po-Hsun; Li, Szu-Yuan; Chen, Jia-Shiong; Lin, Feng-Yen; Chen, Jaw-Wen; Lin, Shing-Jong

    2016-01-01

    Coenzyme Q10 (CoQ10), an antiapoptosis enzyme, is stored in the mitochondria of cells. We investigated whether CoQ10 can attenuate high glucose-induced endothelial progenitor cell (EPC) apoptosis and clarified its mechanism. EPCs were incubated with normal glucose (5 mM) or high glucose (25 mM) enviroment for 3 days, followed by treatment with CoQ10 (10 μM) for 24 hr. Cell proliferation, nitric oxide (NO) production, and JC-1 assay were examined. The specific signal pathways of AMP-activated protein kinase (AMPK), eNOS/Akt, and heme oxygenase-1 (HO-1) were also assessed. High glucose reduced EPC functional activities, including proliferation and migration. Additionally, Akt/eNOS activity and NO production were downregulated in high glucose-stimulated EPCs. Administration of CoQ10 ameliorated high glucose-induced EPC apoptosis, including downregulation of caspase 3, upregulation of Bcl-2, and increase in mitochondrial membrane potential. Furthermore, treatment with CoQ10 reduced reactive oxygen species, enhanced eNOS/Akt activity, and increased HO-1 expression in high glucose-treated EPCs. These effects were negated by administration of AMPK inhibitor. Transplantation of CoQ10-treated EPCs under high glucose conditions into ischemic hindlimbs improved blood flow recovery. CoQ10 reduced high glucose-induced EPC apoptosis and dysfunction through upregulation of eNOS, HO-1 through the AMPK pathway. Our findings provide a potential treatment strategy targeting dysfunctional EPC in diabetic patients. PMID:26682233

  10. Buddleja officinalis inhibits high glucose-induced matrix metalloproteinase activity in human umbilical vein endothelial cells.

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    Lee, Yun Jung; Kang, Dae Gill; Kim, Jin Sook; Lee, Ho Sub

    2008-12-01

    The aim of the present investigation was to investigate whether an aqueous extract of Buddleja officinalis (ABO), a traditional Korean herbal medicine, suppresses the endothelial extracellular matrix degradation under high glucose condition. The incubation with high concentration of glucose (25 mM) increased significantly matrix metalloproteinase (MMP)-2/-9 expressions and activities in primary cultured human umbilical vein endothelial cells (HUVEC). Pretreatment with ABO decreased high glucose-induced increase of MMP-2/-9 activities in a dose-dependent manner. Real time qRT-PCR revealed that high glucose-induced MMP-2/-9 mRNA expression levels were attenuated by pretreatment with ABO. High glucose-induced MCP-1 and IL-8 mRNA expression levels also decreased by ABO. ABO decreased high glucose-induced hydrogen peroxide production, oxidative stress marker. These results provide new insights into the pathophysiological mechanisms for anti-inflammatory properties of ABO in vascular diseases associated with diabetes mellitus. (c) 2008 John Wiley & Sons, Ltd.

  11. Thiamine and benfotiamine prevent increased apoptosis in endothelial cells and pericytes cultured in high glucose.

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    Beltramo, E; Berrone, E; Buttiglieri, S; Porta, M

    2004-01-01

    High glucose induces pathological alterations in small and large vessels, possibly through increased formation of AGE, activation of aldose reductase and protein kinase C, and increased flux through the hexosamine pathway. We showed previously that thiamine and benfotiamine correct delayed replication and increase lactate production in endothelial cells subjected to high glucose. We now aim at verifying the effects of thiamine and benfotiamine on cell cycle, apoptosis, and expression of adhesion molecules in endothelial cells and pericytes, under high ambient glucose. Human umbilical vein endothelial cells and bovine retinal pericytes were cultured in normal (5.6 mmol/L) or high (28 mmol/L) glucose, with or without thiamine or benfotiamine, 50 or 100 micro mol/L. Apoptosis was determined by two separate ELISA methods, measuring DNA fragmentation and caspase-3 activity, respectively. Cell cycle and integrin subunits alpha3, alpha5, and beta1 concentration were measured by flow cytometry. Apoptosis was increased in high glucose after 3 days of culture, both in endothelium and pericytes. Thiamine and benfotiamine reversed such effects. Neither cell cycle traversal nor integrin concentrations were modified in these experimental conditions. Thiamine and benfotiamine correct increased apoptosis due to high glucose in cultured vascular cells. Further elucidations of the mechanisms through which they work could help set the basis for clinical use of this vitamin in the prevention and/or treatment of diabetic microangiopathy. Copyright 2004 John Wiley & Sons, Ltd.

  12. Anti-angiogenic mechanism of cordycepin on rhesus macaque choroid-retinal endothelial cell line cultured in high glucose condition

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    Xiao-Li Zhu*

    2016-07-01

    Full Text Available AIM: To investigate the angiogenesis effect and protective mechanism of cordycepin on rhesus macaque choroid-retinal endothelial(RF/6Acell line cultured in high glucose condition. METHODS: Cultured RF/6A cells were divided into normal control group, high glucose group and high glucose(HG+ different concentration cordycepin groups(HG+10μg/mL group, HG+50μg/mL group, HG+100μg/mL group. The cell proliferation was assessed using cholecystokinin octapeptide dye after treated for 48h. The cell migration was investigated by a Transwell assay. The tube formation was measured on Matrigel. Furthermore, the impact of cordycepin on high glucose-induced activation of VEGF and VEGF receptor 2(VEGFR-2was tested by Western blot analysis. RESULTS: Compared with normal control group, cell viability markedly increased in high glucose group(PPPPPPvs normal control group, oppositely gradually decreased with the increase of cordycepin concentrations, and had a statistically significant difference vs high glucose group(PCONCLUSION: Cordycepin can suppress the proliferation, migration and tubu formation of RF/6A in high glucose condition, might via inhibiting expression of VEGF and VEGFR-2.

  13. Benfotiamine is similar to thiamine in correcting endothelial cell defects induced by high glucose.

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    Pomero, F; Molinar Min, A; La Selva, M; Allione, A; Molinatti, G M; Porta, M

    2001-01-01

    We investigated the hypothesis that benfotiamine, a lipophilic derivative of thiamine, affects replication delay and generation of advanced glycosylation end-products (AGE) in human umbilical vein endothelial cells cultured in the presence of high glucose. Cells were grown in physiological (5.6 mM) and high (28.0 mM) concentrations of D-glucose, with and without 150 microM thiamine or benfotiamine. Cell proliferation was measured by mitochondrial dehydrogenase activity. AGE generation after 20 days was assessed fluorimetrically. Cell replication was impaired by high glucose (72.3%+/-5.1% of that in physiological glucose, p=0.001). This was corrected by the addition of either thiamine (80.6%+/-2.4%, p=0.005) or benfotiamine (87.5%+/-8.9%, p=0.006), although it not was completely normalized (p=0.001 and p=0.008, respectively) to that in physiological glucose. Increased AGE production in high glucose (159.7%+/-38.9% of fluorescence in physiological glucose, p=0.003) was reduced by thiamine (113.2%+/-16.3%, p=0.008 vs. high glucose alone) or benfotiamine (135.6%+/-49.8%, p=0.03 vs. high glucose alone) to levels similar to those observed in physiological glucose. Benfotiamine, a derivative of thiamine with better bioavailability, corrects defective replication and increased AGE generation in endothelial cells cultured in high glucose, to a similar extent as thiamine. These effects may result from normalization of accelerated glycolysis and the consequent decrease in metabolites that are extremely active in generating nonenzymatic protein glycation. The potential role of thiamine administration in the prevention or treatment of vascular complications of diabetes deserves further investigation.

  14. Aldolase B knockdown prevents high glucose-induced methylglyoxal overproduction and cellular dysfunction in endothelial cells.

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    Jianghai Liu

    Full Text Available We used cultured endothelial cells as a model to examine whether up-regulation of aldolase B and enhanced methylglyoxal (MG formation play an important role in high glucose-induced overproduction of advanced glycosylation endproducts (AGEs, oxidative stress and cellular dysfunction. High glucose (25 mM incubation up-regulated mRNA levels of aldose reductase (an enzyme converting glucose to fructose and aldolase B (a key enzyme that catalyzes MG formation from fructose and enhanced MG formation in human umbilical vein endothelial cells (HUVECs and HUVEC-derived EA. hy926 cells. High glucose-increased MG production in EA. hy926 cells was completely prevented by siRNA knockdown of aldolase B, but unaffected by siRNA knockdown of aldolase A, an enzyme responsible for MG formation during glycolysis. In addition, inhibition of cytochrome P450 2E1 or semicarbazide-sensitive amine oxidase which produces MG during the metabolism of lipid and proteins, respectively, did not alter MG production. Both high glucose (25 mM and MG (30, 100 µM increased the formation of N(ε-carboxyethyl-lysine (CEL, a MG-induced AGE, oxidative stress (determined by the generation of oxidized DCF, H(2O(2, protein carbonyls and 8-oxo-dG, O-GlcNAc modification (product of the hexosamine pathway, membrane protein kinase C activity and nuclear translocation of NF-κB in EA. hy926 cells. However, the above metabolic and signaling alterations induced by high glucose were completely prevented by knockdown of aldolase B and partially by application of aminoguanidine (a MG scavenger or alagebrium (an AGEs breaker. In conclusion, efficient inhibition of aldolase B can prevent high glucose-induced overproduction of MG and related cellular dysfunction in endothelial cells.

  15. Nanomolar Caffeic Acid Decreases Glucose Uptake and the Effects of High Glucose in Endothelial Cells.

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    Lucia Natarelli

    Full Text Available Epidemiological studies suggest that moderate and prolonged consumption of coffee is associated with a reduced risk of developing type 2 diabetes but the molecular mechanisms underlying this effect are not known. In this study, we report the effects of physiological concentrations of caffeic acid, easily achievable by normal dietary habits, in endothelial cells cultured in 25 mM of glucose (high glucose, HG. In HG, the presence of 10 nM caffeic acid was associated with a decrease of glucose uptake but not to changes of GLUT-1 membrane localization or mRNA levels. Moreover, caffeic acid countered HG-induced loss of barrier integrity, reducing actin rearrangement and FITC-dextran passage. The decreased flux of glucose associated to caffeic acid affected HG induced apoptosis by down-regulating the expression of initiator (caspase 8 and 9 and effector caspases (caspase 7 and 3 and by increasing the levels of phosphorylated Bcl-2. We also observed that caffeic acid in HG condition was associated to a reduction of p65 subunit nuclear levels with respect to HG alone. NF-κB activation has been shown to lead to apoptosis in HG treated cells and the analysis of the expression of a panel of about 90 genes related to NF-κB signaling pathway revealed that caffeic acid significantly influenced gene expression changes induced by HG. In conclusion, our results suggest that caffeic acid, decreasing the metabolic stress induced by HG, allows the activation of survival mechanisms mediated by a different modulation of NF-κB-related signaling pathways and to the activation of anti-apoptotic proteins.

  16. Ginkgolide B Suppresses TLR4-Mediated Inflammatory Response by Inhibiting the Phosphorylation of JAK2/STAT3 and p38 MAPK in High Glucose-Treated HUVECs

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    Kun Chen

    2017-01-01

    Full Text Available Aim. Ginkgolide B is a Ginkgo biloba leaf extract that has been identified as a natural platelet-activating factor receptor (PAFR antagonist. We investigated the effect of ginkgolide B on high glucose-induced TLR4 activation in human umbilical vein endothelial cells (HUVECs. Methods. Protein expression was analyzed by immunoblotting. Small-interfering RNA (siRNA was used to knock down PAFR and TLR4 expression. Results. Ginkgolide B suppressed the expression of TLR4 and MyD88 that was induced by high glucose. Ginkgolide B also reduced the levels of platelet endothelial cell adhesion molecule-1, interleukin-6, and monocyte chemotactic protein 1. Further, we examined the association between PAFR and TLR4 by coimmunoprecipitation. The result showed that high glucose treatment caused the binding of PAFR and TLR4, whereas ginkgolide B abolished this binding. The functional analysis indicated that PAFR siRNA treatment reduced TLR4 expression, and TLR4 siRNA treatment decreased PAFR expression in high glucose-treated HUVECs, further supporting the coimmunoprecipitation data. Ginkgolide B inhibited the phosphorylation of Janus kinase 2 (JAK2/signal transducer and activator of transcription 3 (STAT3 and p38 mitogen-activated protein kinase (MAPK. Conclusion. Ginkgolide B exerted protective effects by inhibiting the TLR4-mediated inflammatory response in high glucose-treated endothelial cells. The mechanism of action of ginkgolide B might be associated with inhibition of the JAK2/STAT3 and p38 MAPK phosphorylation.

  17. Effect of essential fatty acids on glucose-induced cytotoxicity to retinal vascular endothelial cells

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    Shen Junhui

    2012-07-01

    Full Text Available Abstract Background Diabetic retinopathy is a major complication of dysregulated hyperglycemia. Retinal vascular endothelial cell dysfunction is an early event in the pathogenesis of diabetic retinopathy. Studies showed that hyperglycemia-induced excess proliferation of retinal vascular endothelial cells can be abrogated by docosahexaenoic acid (DHA, 22:6 ω-3 and eicosapentaenoic acid (EPA, 20:5 ω-3. The influence of dietary omega-3 PUFA on brain zinc metabolism has been previously implied. Zn2+ is essential for the activity of Δ6 desaturase as a co-factor that, in turn, converts essential fatty acids to their respective long chain metabolites. Whether essential fatty acids (EFAs α-linolenic acid and linoleic acid have similar beneficial effect remains poorly understood. Methods RF/6A cells were treated with different concentrations of high glucose, α-linolenic acid and linoleic acid and Zn2+. The alterations in mitochondrial succinate dehydrogenase enzyme activity, cell membrane fluidity, reactive oxygen species generation, SOD enzyme and vascular endothelial growth factor (VEGF secretion were evaluated. Results Studies showed that hyperglycemia-induced excess proliferation of retinal vascular endothelial cells can be abrogated by both linoleic acid (LA and α-linolenic acid (ALA, while the saturated fatty acid, palmitic acid was ineffective. A dose–response study with ALA showed that the activity of the mitochondrial succinate dehydrogenase enzyme was suppressed at all concentrations of glucose tested to a significant degree. High glucose enhanced fluorescence polarization and microviscocity reverted to normal by treatment with Zn2+ and ALA. ALA was more potent that Zn2+. Increased level of high glucose caused slightly increased ROS generation that correlated with corresponding decrease in SOD activity. ALA suppressed ROS generation to a significant degree in a dose dependent fashion and raised SOD activity significantly. ALA suppressed

  18. The dipeptidyl peptidase-4 (DPP-4) inhibitor teneligliptin functions as antioxidant on human endothelial cells exposed to chronic hyperglycemia and metabolic high-glucose memory.

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    Pujadas, Gemma; De Nigris, Valeria; Prattichizzo, Francesco; La Sala, Lucia; Testa, Roberto; Ceriello, Antonio

    2017-06-01

    Dipeptidyl peptidase-4 inhibitors are widely used in type 2 diabetes. Endothelium plays a crucial role maintaining vascular integrity and function. Chronic exposure to high glucose drives to endothelial dysfunction generating oxidative stress. Teneligliptin is a novel dipeptidyl peptidase-4 inhibitor with antioxidant properties. This study is aimed to verify a potential protective action of teneligliptin in endothelial cells exposed to high glucose. Human umbilical vein endothelial cells were cultured under normal (5 mmol/L) or high glucose (25 mmol/L) during 21 days, or at high glucose during 14 days followed by 7 days at normal glucose, to reproduce the high-metabolic memory state. During this period, different concentrations of teneligliptin (0.1, 1.0 and 3.0 µmol/L) or sitagliptin (0.5 µmol/L) were added to cells. Ribonucleic acid and protein expression were assessed for antioxidant response, proliferation, apoptosis and endoplasmic reticulum stress markers. Teneligliptin promotes the antioxidant response in human umbilical vein endothelial cells, reducing ROS levels and inducing Nrf2-target genes messenger ribonucleic acid expression. Teneligliptin, but not sitagliptin, reduces the expression of the nicotine amide adenine dinucleotide phosphate oxidase regulatory subunit P22 -phox , however, both blunt the high glucose-induced increase of TXNIP. Teneligliptin improves proliferation rates in human umbilical vein endothelial cells exposed to high glucose, regulating the expression of cell-cycle inhibitors markers (P53, P21 and P27), and reducing proapoptotic genes (BAX and CASP3), while promotes BCL2 expression. Teneligliptin ameliorates high glucose-induced endoplasmic reticulum stress reducing the expression of several markers (BIP, PERK, ATF4, CHOP, IRE1a and ATF6). Teneligliptin has antioxidant properties, ameliorates oxidative stress and apoptotic phenotype and it can overcome the metabolic memory effect, induced by chronic exposure to high

  19. PP2A contributes to endothelial death in high glucose: inhibition by benfotiamine.

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    Du, Y; Kowluru, A; Kern, T S

    2010-12-01

    Endothelial death is critical in diabetic vascular diseases, but regulating factors have been only partially elucidated. Phosphatases play important regulatory roles in cell metabolism, but have not previously been implicated in hyperglycemia-induced cell death. We investigated the role of the phosphatase, type 2A protein phosphatase (PP2A), in hyperglycemia-induced changes in signaling and death in bovine aortic endothelial cells (BAEC). We explored also the influence of benfotiamine on this phosphatase. Activation of PP2A was assessed in BAEC by the extent of methylation and measurement of activity, and the enzyme was inhibited using selective pharmacological (okadaic acid, sodium fostriecin) and molecular (small interfering RNA) approaches. BAECs cultured in 30 mM glucose significantly increased PP2A methylation and activity, and PP2A inhibitors blocked these abnormalities. PP2A activity was increased also in aorta and retina from diabetic rats. NF-κB activity and cell death in BAEC were significantly increased in 30 mM glucose and inhibited by PP2A inhibition. NF-κB played a role in the hyperglycemia-induced death of BAEC, since blocking its translocation with SN50 also inhibited cell death. Inhibition of PP2A blocked the hyperglycemia-induced dephosphorylation of NF-κB and Bad, thus favoring cell survival. Incubation of benfotiamine with BAEC inhibited the high glucose-induced activation of PP2A and NF-κB and cell death, as well as several other metabolic defects, which likewise were inhibited by inhibitors of PP2A. Activation of PP2A contributes to endothelial cell death in high glucose, and beneficial actions of benfotiamine are due, at least in part, to inhibition of PP2A activation.

  20. High glucose, glucose fluctuation and carbonyl stress enhance brain microvascular endothelial barrier dysfunction: Implications for diabetic cerebral microvasculature.

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    Li, Wei; Maloney, Ronald E; Aw, Tak Yee

    2015-08-01

    We previously demonstrated that in normal glucose (5mM), methylglyoxal (MG, a model of carbonyl stress) induced brain microvascular endothelial cell (IHEC) dysfunction that was associated with occludin glycation and prevented by N-acetylcysteine (NAC). Herein, we investigated the impact of high glucose and low GSH, conditions that mimicked the diabetic state, on MG-induced IHEC dysfunction. MG-induced loss of transendothelial electrical resistance (TEER) was potentiated in IHECs cultured for 7 or 12 days in 25 mM glucose (hyperglycemia); moreover, barrier function remained disrupted 6h after cell transfer to normal glucose media (acute glycemic fluctuation). Notably, basal occludin glycation was elevated under these glycemic states. TEER loss was exaggerated by inhibition of glutathione (GSH) synthesis and abrogated by NAC, which corresponded to GSH decreases and increases, respectively. Significantly, glyoxalase II activity was attenuated in hyperglycemic cells. Moreover, hyperglycemia and GSH inhibition increased MG accumulation, consistent with a compromised capacity for MG elimination. α-Oxoaldehydes (MG plus glyoxal) levels were elevated in streptozotocin-induced diabetic rat plasma. Immunohistochemistry revealed a prevalence of MG-positive, but fewer occludin-positive microvessels in the diabetic brain in vivo, and Western analysis confirmed an increase in MG-occludin adducts. These results provide the first evidence that hyperglycemia and acute glucose fluctuation promote MG-occludin formation and exacerbate brain microvascular endothelial dysfunction. Low occludin expression and high glycated-occludin contents in diabetic brain in vivo are factors that would contribute to the dysfunction of the cerebral microvasculature during diabetes. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  1. High glucose, glucose fluctuation and carbonyl stress enhance brain microvascular endothelial barrier dysfunction: Implications for diabetic cerebral microvasculature

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    Wei Li

    2015-08-01

    Full Text Available We previously demonstrated that in normal glucose (5 mM, methylglyoxal (MG, a model of carbonyl stress induced brain microvascular endothelial cell (IHEC dysfunction that was associated with occludin glycation and prevented by N-acetylcysteine (NAC. Herein, we investigated the impact of high glucose and low GSH, conditions that mimicked the diabetic state, on MG-induced IHEC dysfunction. MG-induced loss of transendothelial electrical resistance (TEER was potentiated in IHECs cultured for 7 or 12 days in 25 mM glucose (hyperglycemia; moreover, barrier function remained disrupted 6 h after cell transfer to normal glucose media (acute glycemic fluctuation. Notably, basal occludin glycation was elevated under these glycemic states. TEER loss was exaggerated by inhibition of glutathione (GSH synthesis and abrogated by NAC, which corresponded to GSH decreases and increases, respectively. Significantly, glyoxalase II activity was attenuated in hyperglycemic cells. Moreover, hyperglycemia and GSH inhibition increased MG accumulation, consistent with a compromised capacity for MG elimination. α-Oxoaldehydes (MG plus glyoxal levels were elevated in streptozotocin-induced diabetic rat plasma. Immunohistochemistry revealed a prevalence of MG-positive, but fewer occludin-positive microvessels in the diabetic brain in vivo, and Western analysis confirmed an increase in MG–occludin adducts. These results provide the first evidence that hyperglycemia and acute glucose fluctuation promote MG–occludin formation and exacerbate brain microvascular endothelial dysfunction. Low occludin expression and high glycated-occludin contents in diabetic brain in vivo are factors that would contribute to the dysfunction of the cerebral microvasculature during diabetes.

  2. Monomeric adiponectin increases cell viability in porcine aortic endothelial cells cultured in normal and high glucose conditions: Data on kinases activation

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    Elena Grossini

    2016-09-01

    Full Text Available We found that monomeric adiponectin was able to increase cell viability in porcine aortic endothelial cells (PAE cultured both in normal and high glucose condition. Moreover, in normal glucose condition monomeric adiponectin increased p38MAPK, Akt, ERK1/2 and eNOS phosphorylation in a dose- and time-dependent way. Also in high glucose condition monomeric adiponectin increased eNOS and above kinases phosphorylation with similar patterns but at lower extent. For interpretation of the data presented in this article, please see the research article “Monomeric adiponectin modulates nitric oxide release and calcium movements in porcine aortic endothelial cells in normal/high glucose conditions” (Grossini et al., in press [1].

  3. Effect of perilipin-5 on apoptosis of cardiac microvascular endothelial cells induced by high fat and high glucose in mice

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    Jin DU

    2017-12-01

    Full Text Available Objective To investigate the effects and mechanisms of perilipin-5 (Plin5 on the apoptosis of mouse cardiac microvascular endothelial cells induced by high fat and high glucose. Methods The mouse cardiac microvascular endothelial cells (MCMECs cultured with high glucose medium were respectively given 0, 100, 300 and 500μmol/L palmitic acid for 24 hours. In order to explore the effects and mechanisms of Plin5 on MCMECs injuries induced by high fat and high glucose, MCMECs exposed to 300μmol/L palmitic acid for 24 hours were divided into control group, Scra siRNA group and Plin5 siRNA group. The control group was only treated with transfection reagent, the Scra siRNA group was given treatment of transfection reagent and garbled RNA, the Plin5 siRNA group was given treatment of transfection reagent and Plin5 specific siRNA. In order to further confirm the specific mechanism of Plin5 in high fat/glucose inducing MCMECs injury, MCMECs in Plin5 siRNA group were divided into vehicle group and N-acetyl cysteine (NAC group, and given the same intervention of high fat. The apoptotic rate was detected by flow cytometry, qRT-PCR and Western blotting were respectively used to detect the mRNA and protein expression of Plin5, and the intracellular reactive oxygen species (ROS level was tested by DHE staining and ELISA kit. Results The apoptotic rate of MCMECs was increased in a fat concentration-dependent manner (P<0.05. Compared with 0μmol/L palmitic acid group, the intracellular ROS content and the expression of Plin5 increased significantly in 300μmol/L palmitic acid group (P<0.05. Compared with the control group and the Scra siRNA group, the intracellular ROS content and apoptotic rate increased significantly in Plin5 siRNA group under the action of 300μmol/L palmitic acid (P<0.05. Compared with the vehicle group, the intracellular ROS content and apoptotic rate decreased remarkably in NAC group (P<0.05. Conclusion With inhibition of oxidative stress

  4. TLQP-21 protects human umbilical vein endothelial cells against high-glucose-induced apoptosis by increasing G6PD expression.

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    Wei Zhang

    Full Text Available Hyperglycemia causes oxidative stress that could damage vascular endothelial cells, leading to cardiovascular complications. The Vgf gene was identified as a nerve growth factor-responsive gene, and its protein product, VGF, is characterized by the presence of partially cleaved products. One of the VGF-derived peptides is TLQP-21, which is composed of 21 amino acids (residues 556-576. Past studies have reported that TLQP-21 could stimulate insulin secretion in pancreatic cells and protect these cells from apoptosis, which suggests that TLQP-21 has a potential function in diabetes therapy. Here, we explore the protective role of TLQP-21 against the high glucose-mediated injury of vascular endothelial cells. Using human umbilical vascular endothelial cells (HUVECs, we demonstrated that TLQP-21 (10 or 50 nM dose-dependently prevented apoptosis under high-glucose (30 mmol/L conditions (the normal glucose concentration is 5.6 mmol/L. TLQP-21 enhanced the expression of NAPDH, resulting in upregulation of glutathione (GSH and a reduction in the levels of reactive oxygen species (ROS. TLQP-21 also upregulated the expression of glucose-6-phosphate dehydrogenase (G6PD, which is known as the main source of NADPH. Knockdown of G6PD almost completely blocked the increase of NADPH induced by TLQP-21, indicating that TLQP-21 functions mainly through G6PD to promote NADPH generation. In conclusion, TLQP-21 could increase G6PD expression, which in turn may increase the synthesis of NADPH and GSH, thereby partially restoring the redox status of vascular endothelial cells under high glucose injury. We propose that TLQP-21 is a promising drug for diabetes therapy.

  5. Effects of Oral Glucose Load on Endothelial Function and on Insulin and Glucose Fluctuations in Healthy Individuals

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    A. Major-Pedersen

    2008-01-01

    Full Text Available Background/aims. Postprandial hyperglycemia, an independent risk factor for cardiovascular disease, is accompanied by endothelial dysfunction. We studied the effect of oral glucose load on insulin and glucose fluctuations, and on postprandial endothelial function in healthy individuals in order to better understand and cope with the postprandial state in insulin resistant individuals. Methods. We assessed post-oral glucose load endothelial function (flow mediated dilation, plasma insulin, and blood glucose in 9 healthy subjects. Results. The largest increases in delta FMD values (fasting FMD value subtracted from postprandial FMD value occurred at 3 hours after both glucose or placebo load, respectively: 4.80±1.41 (P = .009 and 2.34±1.47 (P = .15. Glucose and insulin concentrations achieved maximum peaks at one hour post-glucose load. Conclusion. Oral glucose load does not induce endothelial dysfunction in healthy individuals with mean insulin and glucose values of 5.6 mmol/L and 27.2 mmol/L, respectively, 2 hours after glucose load.

  6. Metformin and liraglutide ameliorate high glucose-induced oxidative stress via inhibition of PKC-NAD(P)H oxidase pathway in human aortic endothelial cells.

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    Batchuluun, Battsetseg; Inoguchi, Toyoshi; Sonoda, Noriyuki; Sasaki, Shuji; Inoue, Tomoaki; Fujimura, Yoshinori; Miura, Daisuke; Takayanagi, Ryoichi

    2014-01-01

    Metformin and glucagon like peptide-1 (GLP-1) prevent diabetic cardiovascular complications and atherosclerosis. However, the direct effects on hyperglycemia-induced oxidative stress in endothelial cells are not fully understood. Thus, we aimed to evaluate the effects of metformin and a GLP-1 analog, liraglutide on high glucose-induced oxidative stress. Production of reactive oxygen species (ROS), activation of protein kinase C (PKC) and NAD(P)H oxidase, and changes in signaling molecules in response to high glucose exposure were evaluated in human aortic endothelial cells with and without treatment of metformin and liraglutide, alone or in combination. PKC-NAD(P)H oxidase pathway was assessed by translocation of GFP-fused PKCβ2 isoform and GFP-fused p47phox, a regulatory subunit of NAD(P)H oxidase, in addition to endogenous PKC phosphorylation and NAD(P)H oxidase activity. High glucose-induced ROS overproduction was blunted by metformin or liraglutide treatment, with a further decrease by a combination of these drugs. Exposure to high glucose caused PKCβ2 translocation and a time-dependent phosphorylation of endogenous PKC but failed to induce its translocation and phosphorylation in the cells treated with metformin and liraglutide. Furthermore, both drugs inhibited p47phox translocation and NAD(P)H oxidase activation, and prevented the high glucose-induced changes in intracellulalr diacylglycerol (DAG) level and phosphorylation of AMP-activated protein kinase (AMPK). A combination of these drugs further enhanced all of these effects. Metformin and liraglutide ameliorate high glucose-induced oxidative stress by inhibiting PKC-NAD(P)H oxidase pathway. A combination of these two drugs provides augmented protective effects, suggesting the clinical usefulness in prevention of diabetic vascular complications. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Naringin Protects Against High Glucose-Induced Human Endothelial Cell Injury Via Antioxidation and CX3CL1 Downregulation

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    Guilin Li

    2017-08-01

    Full Text Available Background/Aims: The induction of endothelial injury by hyperglycemia in diabetes has been widely accepted. Naringin is a bio-flavonoid. Some studies showed that naringin alleviates diabetic complications, but the exact mechanisms by which naringin improves diabetic anomalies are not yet fully understood. The aim of this research was to study the protective effect of naringin on high glucose-induced injury of human umbilical vein endothelial cells (HUVECs. Methods: HUVECs were cultured with or without high glucose in the absence or presence of naringin for 5 days. The expression of CX3CL1 was determined by quantitative real-time RT-PCR (qPCR and western blot. The cellular bioenergetic analysis oxygen consumption rate (OCR was measured with a Seahorse Bioscience XF analyzer. Results: The production of reactive oxygen species (ROS, the expression of CX3CL1 and the level of AKT phosphorylation were increased in HUVECs cultured with high glucose compared with controls. However, naringin rescued these increases in ROS production, CX3CL1 expression and AKT phosphorylation. Nitric oxide (NO production and OCR were lower in the high glucose group, and naringin restored the changes induced by high glucose. Molecular docking results suggested that Naringin might interact with the CX3CL1 protein. Conclusion: Naringin protects HUVECs from high-glucose-induced damage through its antioxidant properties by downregulating CX3CL1 and by improving mitochondrial function.

  8. Monomeric adiponectin modulates nitric oxide release and calcium movements in porcine aortic endothelial cells in normal/high glucose conditions.

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    Grossini, Elena; Farruggio, Serena; Qoqaiche, Fatima; Raina, Giulia; Camillo, Lara; Sigaudo, Lorenzo; Mary, David; Surico, Nicola; Surico, Daniela

    2016-09-15

    Perivascular adipose tissue can be involved in the process of cardiovascular pathology through the release of adipokines, namely adiponectins. Monomeric adiponectin has been shown to increase coronary blood flow in anesthetized pigs through increased nitric oxide (NO) release and the involvement of adiponectin receptor 1 (AdipoR1). The present study was therefore planned to examine the effects of monomeric adiponectin on NO release and Ca(2+) transients in porcine aortic endothelial cells (PAEs) in normal/high glucose conditions and the related mechanisms. PAEs were treated with monomeric adiponectin alone or in the presence of intracellular kinases blocker, AdipoR1 and Ca(2+)-ATPase pump inhibitors. The role of Na(+)/Ca(2+) exchanger was examined in experiments performed in zero Na(+) medium. NO release and intracellular Ca(2+) were measured through specific probes. In PAE cultured in normal glucose conditions, monomeric adiponectin elevated NO production and [Ca(2+)]c. Similar effects were observed in high glucose conditions, although the response was lower and not transient. The Ca(2+) mobilized by monomeric adiponectin originated from an intracellular pool thapsigargin- and ATP-sensitive and from the extracellular space. Moreover, the effects of monomeric adiponectin were prevented by kinase blockers and AdipoR1 inhibitor. Finally, in normal glucose condition, a role for Na(+)/Ca(2+) exchanger and Ca(2+)-ATPase pump in restoring Ca(2+) was found. Our results add new information about the control of endothelial function elicited by monomeric adiponectin, which would be achieved by modulation of NO release and Ca(2+) transients. A signalling related to Akt, ERK1/2 and p38MAPK downstream AdipoR1 would be involved. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Effects of oral glucose load on endothelial function and on insulin and glucose fluctuations in healthy individuals

    DEFF Research Database (Denmark)

    Major-Pedersen, A; Ihlemann, N; Hermann, T S

    2008-01-01

    to better understand and cope with the postprandial state in insulin resistant individuals. METHODS: We assessed post-oral glucose load endothelial function (flow mediated dilation), plasma insulin, and blood glucose in 9 healthy subjects. RESULTS: The largest increases in delta FMD values (fasting FMD......BACKGROUND/AIMS: Postprandial hyperglycemia, an independent risk factor for cardiovascular disease, is accompanied by endothelial dysfunction. We studied the effect of oral glucose load on insulin and glucose fluctuations, and on postprandial endothelial function in healthy individuals in order...... value subtracted from postprandial FMD value) occurred at 3 hours after both glucose or placebo load, respectively: 4.80 +/- 1.41 (P = .009) and 2.34 +/- 1.47 (P = .15). Glucose and insulin concentrations achieved maximum peaks at one hour post-glucose load. CONCLUSION: Oral glucose load does not induce...

  10. Benfotiamine counteracts glucose toxicity effects on endothelial progenitor cell differentiation via Akt/FoxO signaling.

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    Marchetti, Valentina; Menghini, Rossella; Rizza, Stefano; Vivanti, Alessia; Feccia, Tiziana; Lauro, Davide; Fukamizu, Akiyoshi; Lauro, Renato; Federici, Massimo

    2006-08-01

    Dysfunction of mature endothelial cells is thought to play a major role in both micro- and macrovascular complications of diabetes. However, recent advances in biology of endothelial progenitor cells (EPCs) have highlighted their involvement in diabetes complications. To determine the effect of glucotoxicity on EPCs, human EPCs have been isolated from peripheral blood mononuclear cells of healthy donors and cultured in the presence or absence of high glucose (33 mmol/l) or high glucose plus benfotiamine to scavenge glucotoxicity. Morphological analysis revealed that high glucose significantly affected the number of endothelial cell colony forming units, uptake and binding of acLDL and Lectin-1, and the ability to differentiate into CD31- and vascular endothelial growth factor receptor 2-positive cells. Functional analysis outlined a reduced EPC involvement in de novo tube formation, when cocultured with mature endothelial cells (human umbilical vein endothelial cells) on matrigel. To explain the observed phenotypes, we have investigated the signal transduction pathways known to be involved in EPC growth and differentiation. Our results indicate that hyperglycemia impairs EPC differentiation and that the process can be restored by benfotiamine administration, via the modulation of Akt/FoxO1 activity.

  11. Far infra-red therapy promotes ischemia-induced angiogenesis in diabetic mice and restores high glucose-suppressed endothelial progenitor cell functions

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    Huang Po-Hsun

    2012-08-01

    Full Text Available Abstract Background Far infra-red (IFR therapy was shown to exert beneficial effects in cardiovascular system, but effects of IFR on endothelial progenitor cell (EPC and EPC-related vasculogenesis remain unclear. We hypothesized that IFR radiation can restore blood flow recovery in ischemic hindlimb in diabetic mice by enhancement of EPCs functions and homing process. Materials and methods Starting at 4 weeks after the onset of diabetes, unilateral hindlimb ischemia was induced in streptozotocine (STZ-induced diabetic mice, which were divided into control and IFR therapy groups (n = 6 per group. The latter mice were placed in an IFR dry sauna at 34°C for 30 min once per day for 5 weeks. Results Doppler perfusion imaging demonstrated that the ischemic limb/normal side blood perfusion ratio in the thermal therapy group was significantly increased beyond that in controls, and significantly greater capillary density was seen in the IFR therapy group. Flow cytometry analysis showed impaired EPCs (Sca-1+/Flk-1+ mobilization after ischemia surgery in diabetic mice with or without IFR therapy (n = 6 per group. However, as compared to those in the control group, bone marrow-derived EPCs differentiated into endothelial cells defined as GFP+/CD31+ double-positive cells were significantly increased in ischemic tissue around the vessels in diabetic mice that received IFR radiation. In in-vitro studies, cultured EPCs treated with IFR radiation markedly augmented high glucose-impaired EPC functions, inhibited high glucose-induced EPC senescence and reduced H2O2 production. Nude mice received human EPCs treated with IFR in high glucose medium showed a significant improvement in blood flow recovery in ischemic limb compared to those without IFR therapy. IFR therapy promoted blood flow recovery and new vessel formation in STZ-induced diabetic mice. Conclusions Administration of IFR therapy promoted collateral flow recovery and new vessel formation in STZ

  12. Metformin and Resveratrol Inhibited High Glucose-Induced Metabolic Memory of Endothelial Senescence through SIRT1/p300/p53/p21 Pathway.

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    Zhang, Erli; Guo, Qianyun; Gao, Haiyang; Xu, Ruixia; Teng, Siyong; Wu, Yongjian

    2015-01-01

    Endothelial senescence plays crucial roles in diabetic vascular complication. Recent evidence indicated that transient hyperglycaemia could potentiate persistent diabetic vascular complications, a phenomenon known as "metabolic memory." Although SIRT1 has been demonstrated to mediate high glucose-induced endothelial senescence, whether and how "metabolic memory" would affect endothelial senescence through SIRT1 signaling remains largely unknown. In this study, we investigated the involvement of SIRT1 axis as well as the protective effects of resveratrol (RSV) and metformin (MET), two potent SIRT1 activators, during the occurrence of "metabolic memory" of cellular senescence (senescent "memory"). Human umbilical vascular endothelial cells (HUVECs) were cultured in either normal glucose (NG)/high glucose (HG) media for 6 days, or 3 days of HG followed by 3 days of NG (HN), with or without RSV or MET treatment. It was shown that HN incubation triggered persistent downregulation of deacetylase SIRT1 and upregulation of acetyltransferase p300, leading to sustained hyperacetylation (at K382) and activation of p53, and subsequent p53/p21-mediated senescent "memory." In contrast, senescent "memory" was abrogated by overexpression of SIRT1 or knockdown of p300. Interestingly, we found that SIRT1 and p300 could regulate each other in response to HN stimulation, suggesting that a delicate balance between acetyltransferases and deacetylases may be particularly important for sustained acetylation and activation of non-histone proteins (such as p53), and eventually the occurrence of "metabolic memory." Furthermore, we found that RSV or MET treatment prevented senescent "memory" by modulating SIRT1/p300/p53/p21 pathway. Notably, early and continuous treatment of MET, but not RSV, was particularly important for preventing senescent "memory." In conclusion, short-term high glucose stimulation could induce sustained endothelial senescence via SIRT1/p300/p53/p21 pathway. RVS or MET

  13. miR-Let7A Controls the Cell Death and Tight Junction Density of Brain Endothelial Cells under High Glucose Condition.

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    Song, Juhyun; Yoon, So Ra; Kim, Oh Yoen

    2017-01-01

    Hyperglycemia-induced stress in the brain of patients with diabetes triggers the disruption of blood-brain barrier (BBB), leading to diverse neurological diseases including stroke and dementia. Recently, the role of microRNA becomes an interest in the research for deciphering the mechanism of brain endothelial cell damage under hyperglycemia. Therefore, we investigated whether mircoRNA Let7A (miR-Let7A) controls the damage of brain endothelial (bEnd.3) cells against high glucose condition. Cell viability, cell death marker expressions (p-53, Bax, and cleaved poly ADP-ribose polymerase), the loss of tight junction proteins (ZO-1 and claudin-5), proinflammatory response (interleukin-6, tumor necrosis factor- α ), inducible nitric oxide synthase, and nitrite production were confirmed using MTT, reverse transcription-PCR, quantitative-PCR, Western blotting, immunofluorescence, and Griess reagent assay. miR-Let7A overexpression significantly prevented cell death and loss of tight junction proteins and attenuated proinflammatory response and nitrite production in the bEnd.3 cells under high glucose condition. Taken together, we suggest that miR-Let7A may attenuate brain endothelial cell damage by controlling cell death signaling, loss of tight junction proteins, and proinflammatory response against high glucose stress. In the future, the manipulation of miR-Let7A may be a novel solution in controlling BBB disruption which leads to the central nervous system diseases.

  14. Kaempferol targets estrogen-related receptor α and suppresses the angiogenesis of human retinal endothelial cells under high glucose conditions.

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    Wu, Yan; Zhang, Qinmei; Zhang, Rui

    2017-12-01

    Diabetic retinopathy (DR) is the most common complication of diabetes and a major cause of new-onset blindness in the developed world. The present study aimed to examine the effect of kaempferol on high glucose-induced human retinal endothelial cells (HRECs) in vitro . The expression levels of various mRNAs and proteins were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. The target of kaempferol was determined using a luciferase reporter assay. In addition, HREC proliferation, migration and cell sprouting were determined using Cell Counting kit-8, wound scratch and tube formation assays, respectively. RT-qPCR and western blotting results showed that treatment with 30 mM glucose for 12, 24 and 48 h increased the expression level of estrogen-related receptor α (ERRα) mRNA and protein. The luciferase reporter assay demonstrated that kaempferol inhibited ERRα activity in HRECs. Compared with 5 mM normal glucose treatment, high (30 mM) glucose significantly promoted the proliferation, migration and tube formation of HRECs, which was antagonized by 10 and 30 µM kaempferol in a dose-dependent manner. Treatment with 30 mM glucose also increased the expression of vascular endothelial growth factor (VEGF) mRNA and protein, and the expression levels of VEGF mRNA and protein were suppressed by kaempferol (10 and 30 µM). Kaempferol (30 µM) treatment also increased the expression levels of thrombospondin 1 (TSP-1) and a disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS-1) mRNA; however, TSP-1 and ADAMTS-1 levels did not differ between high glucose and normal (5 mM) glucose conditions. The results of this study suggest that kaempferol targets ERRα and suppresses the angiogenesis of HRECs under high glucose conditions. Kaempferol may be a potential drug for use in controlling the progression of DR; however, in vivo studies are required to evaluate its efficacy and safety.

  15. Downregulation of Lysyl Oxidase Protects Retinal Endothelial Cells From High Glucose-Induced Apoptosis.

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    Kim, Dongjoon; Mecham, Robert P; Trackman, Philip C; Roy, Sayon

    2017-05-01

    To investigate the effect of reducing high glucose (HG)-induced lysyl oxidase (LOX) overexpression and increased activity on retinal endothelial cell apoptosis. Rat retinal endothelial cells (RRECs) were grown in normal (N) or HG (30 mM glucose) medium for 7 days. In parallel, RRECs were grown in HG medium and transfected with LOX small interfering RNA (siRNA), scrambled siRNA as control, or exposed to β-aminopropionitrile (BAPN), a LOX inhibitor. LOX expression, AKT activation, and caspase-3 activity were determined by Western blot (WB) analysis and apoptosis by differential dye staining assay. Moreover, to determine whether diabetes-induced LOX overexpression alters AKT activation and promotes apoptosis, changes in LOX expression, AKT phosphorylation, caspase-3 activation, and Bax expression were assessed in retinas of streptozotocin (STZ)-induced diabetic mice and LOX heterozygous knockout (LOX+/-) mice. WB analysis indicated significant LOX overexpression and reduced AKT activation under HG condition in RRECs. Interestingly, when cells grown in HG were transfected with LOX siRNA or exposed to BAPN, the number of apoptotic cells was significantly decreased concomitant with increased AKT phosphorylation. Diabetic mouse retinas exhibited LOX overexpression, decreased AKT phosphorylation, and increased Bax and caspase-3 activation compared to values in nondiabetic mice. In LOX+/- mice, reduced LOX levels were observed with increased AKT activity, and reduced Bax and caspase-3 activity. Furthermore, decreased levels of LOX in the LOX+/- mice was protective against diabetes-induced apoptosis. Findings from this study indicate that preventing LOX overexpression may be protective against HG-induced apoptosis in retinal vascular cells associated with diabetic retinopathy.

  16. Endothelial microparticle-mediated transfer of MicroRNA-126 promotes vascular endothelial cell repair via SPRED1 and is abrogated in glucose-damaged endothelial microparticles.

    Science.gov (United States)

    Jansen, Felix; Yang, Xiaoyan; Hoelscher, Marion; Cattelan, Arianna; Schmitz, Theresa; Proebsting, Sebastian; Wenzel, Daniela; Vosen, Sarah; Franklin, Bernardo S; Fleischmann, Bernd K; Nickenig, Georg; Werner, Nikos

    2013-10-29

    Repair of the endothelium after vascular injury is crucial for preserving endothelial integrity and preventing the development of vascular disease. The underlying mechanisms of endothelial cell repair are largely unknown. We sought to investigate whether endothelial microparticles (EMPs), released from apoptotic endothelial cells (ECs), influence EC repair. Systemic treatment of mice with EMPs after electric denudation of the endothelium accelerated reendothelialization in vivo. In vitro experiments revealed that EMP uptake in ECs promotes EC migration and proliferation, both critical steps in endothelial repair. To dissect the underlying mechanisms, Taqman microRNA array was performed, and microRNA (miR)-126 was identified as the predominantly expressed miR in EMPs. The following experiments demonstrated that miR-126 was transported into recipient human coronary artery endothelial cells by EMPs and functionally regulated the target protein sprouty-related, EVH1 domain-containing protein 1 (SPRED1). Knockdown of miR-126 in EMPs abrogated EMP-mediated effects on human coronary artery endothelial cell migration and proliferation in vitro and reendothelialization in vivo. Interestingly, after simulating diabetic conditions, EMPs derived from glucose-treated ECs contained significantly lower amounts of miR-126 and showed reduced endothelial repair capacity in vitro and in vivo. Finally, expression analysis of miR-126 in circulating microparticles from 176 patients with stable coronary artery disease with and without diabetes mellitus revealed a significantly reduced miR-126 expression in circulating microparticles from diabetic patients. Endothelial microparticles promote vascular endothelial repair by delivering functional miR-126 into recipient cells. In pathological hyperglycemic conditions, EMP-mediated miR-126-induced EC repair is altered.

  17. RXR agonists inhibit high glucose-induced upregulation of inflammation by suppressing activation of the NADPH oxidase-nuclear factor-κB pathway in human endothelial cells.

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    Ning, R B; Zhu, J; Chai, D J; Xu, C S; Xie, H; Lin, X Y; Zeng, J Z; Lin, J X

    2013-12-13

    An inflammatory response induced by high glucose is a cause of endothelial dysfunction in diabetes and is an important contributing link to atherosclerosis. Diabetes is an independent risk factor of atherosclerosis and activation of retinoid X receptor (RXR) has been shown to exert anti-atherogenic effects. In the present study, we examined the effects of the RXR ligands 9-cis-retinoic acid (9-cis-RA) and SR11237 on high glucose-induced inflammation in human umbilical endothelial vein endothelial cells (HUVECs) and explored the potential mechanism. Our results showed that the inflammation induced by high-glucose in HUVECs was mainly mediated by the activation of nuclear factor-B (NF- κB). High glucose-induced expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were in comparison, significantly decreased by treatment with RXR. The effect of RXR agonists was mainly due to the inhibition of NF-κB activation. Using pharmacological inhibitors and siRNA, we confirmed that nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was an upstream activator of NF-κB. Furthermore, RXR agonists significantly inhibited high glucose-induced activation of NADPH oxidase and significantly decreased the production of reactive oxygen species (ROS). To explore whether the rapid inhibitory effects of RXR agonists were in fact mediated by RXR, we examined the effect of RXR downregulation by RXR siRNA. Our results showed that RXR siRNA largely abrogated the effects of RXR agonists, suggesting the requirement of RXR expression. Therefore, we have shown that RXR is involved in the regulation of NADPH oxidase- NF-κB signal pathway, as the RXR ligands antagonized the inflammatory response in HUVECs induced by high glucose.

  18. High glucose attenuates shear-induced changes in endothelial hydraulic conductivity by degrading the glycocalyx.

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    Sandra V Lopez-Quintero

    Full Text Available Diabetes mellitus is a risk factor for cardiovascular disease; however, the mechanisms through which diabetes impairs homeostasis of the vasculature have not been completely elucidated. The endothelium interacts with circulating blood through the surface glycocalyx layer, which serves as a mechanosensor/transducer of fluid shear forces leading to biomolecular responses. Atherosclerosis localizes typically in regions of low or disturbed shear stress, but in diabetics, the distribution is more diffuse, suggesting that there is a fundamental difference in the way cells sense shear forces. In the present study, we examined the effect of hyperglycemia on mechanotranduction in bovine aortic endothelial cells (BAEC. After six days in high glucose media, we observed a decrease in heparan sulfate content coincident with a significant attenuation of the shear-induced hydraulic conductivity response, lower activation of eNOS after exposure to shear, and reduced cell alignment with shear stress. These studies are consistent with a diabetes-induced change to the glycocalyx altering endothelial response to shear stress that could affect the distribution of atherosclerotic plaques.

  19. Relationship between fluctuations in glucose levels measured by continuous glucose monitoring and vascular endothelial dysfunction in type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Torimoto Keiichi

    2013-01-01

    Full Text Available Abstract Background Fluctuations in blood glucose level cause endothelial dysfunction and play a critical role in onset and/or progression of atherosclerosis. We hypothesized that fluctuation in blood glucose levels correlate with vascular endothelial dysfunction and that this relationship can be assessed using common bedside medical devices. Methods Fluctuations in blood glucose levels were measured over 24 hours by continuous glucose monitoring (CGM on admission day 2 in 57 patients with type 2 diabetes mellitus. The reactive hyperemia index (RHI, an index of vascular endothelial function, was measured using peripheral arterial tonometry (EndoPAT on admission day 3. Results The natural logarithmic-scaled RHI (L_RHI correlated with SD (r=−0.504; PPP=0.001 and percentage of time ≥200 mg/dl (r=−0.292; P=0.028. In 12 patients with hypoglycemia, L_RHI also correlated with the percentage of time at hypoglycemia (r=−0.589; P=0.044. L_RHI did not correlate with HbA1c or fasting plasma glucose levels. Furthermore, L_RHI did not correlate with LDL cholesterol, HDL cholesterol, and triglyceride levels or with systolic and diastolic blood pressures. Finally, multivariate analysis identified MAGE as the only significant determinant of L_RHI. Conclusions Fluctuations in blood glucose levels play a significant role in vascular endothelial dysfunction in type 2 diabetes. Trial registration UMIN000007581

  20. Regulation of intracellular glucose and polyol pathway by thiamine and benfotiamine in vascular cells cultured in high glucose.

    Science.gov (United States)

    Berrone, Elena; Beltramo, Elena; Solimine, Carmela; Ape, Alessandro Ubertalli; Porta, Massimo

    2006-04-07

    Hyperglycemia is a causal factor in the development of the vascular complications of diabetes. One of the biochemical mechanisms activated by excess glucose is the polyol pathway, the key enzyme of which, aldose reductase, transforms d-glucose into d-sorbitol, leading to imbalances of intracellular homeostasis. We aimed at verifying the effects of thiamine and benfotiamine on the polyol pathway, transketolase activity, and intracellular glucose in endothelial cells and pericytes under high ambient glucose. Human umbilical vein endothelial cells and bovine retinal pericytes were cultured in normal (5.6 mmol/liter) or high (28 mmol/liter) glucose, with or without thiamine or benfotiamine 50 or 100 mumol/liter. Transketolase and aldose reductase mRNA expression was determined by reverse transcription-PCR, and their activity was measured spectrophotometrically; sorbitol concentrations were quantified by gas chromatography-mass spectrometry and intracellular glucose concentrations by fluorescent enzyme-linked immunosorbent assay method. Thiamine and benfotiamine reduce aldose reductase mRNA expression, activity, sorbitol concentrations, and intracellular glucose while increasing the expression and activity of transketolase, for which it is a coenzyme, in human endothelial cells and bovine retinal pericytes cultured in high glucose. Thiamine and benfotiamine correct polyol pathway activation induced by high glucose in vascular cells. Activation of transketolase may shift excess glycolytic metabolites into the pentose phosphate cycle, accelerate the glycolytic flux, and reduce intracellular free glucose, thereby preventing its conversion to sorbitol. This effect on the polyol pathway, together with other beneficial effects reported for thiamine in high glucose, could justify testing thiamine as a potential approach to the prevention and/or treatment of diabetic complications.

  1. High glucose induced oxidative stress and apoptosis in cardiac microvascular endothelial cells are regulated by FoxO3a.

    Directory of Open Access Journals (Sweden)

    Chaoming Peng

    Full Text Available Cardiac microvascular endothelial cells (CMECs dysfunction contributes to cardiovascular complications in diabetes, whereas, the underlying mechanism is not fully clarified. FoxO transcription factors are involved in apoptosis and reactive oxygen species (ROS production. Therefore, the present study was designed to elucidate the potential role of FoxO3a on the CMECs injury induced by high glucose.CMECs were isolated from hearts of adult rats and cultured in normal or high glucose medium for 6 h, 12 h and 24 h respectively. To down-regulate FoxO3a expression, CMECs were transfected with FoxO3a siRNA. ROS accumulation and apoptosis in CMECs were assessed by dihydroethidine (DHE staining and TUNEL assay respectively. Moreover, the expressions of Akt, FoxO3a, Bim and BclxL in CMECs were assessed by Western blotting assay.ROS accumulation in CMECs was significantly increased after high glucose incubation for 6 to 24 h. Meanwhile, high glucose also increased apoptosis in CMECs, correlated with decreased the phosphorylation expressions of Akt and FoxO3a. Moreover, high glucose incubation increased the expression of Bim, whereas increased anti-apoptotic protein BclxL. Furthermore, siRNA target FoxO3a silencing enhanced the ROS accumulation, whereas suppressed apoptosis in CMECs. FoxO3a silencing also abolished the disturbance of Bcl-2 proteins induced by high glucose in CMECs.Our data provide evidence that high glucose induced FoxO3a activation which suppressed ROS accumulation, and in parallel, resulted in apoptosis of CMECs.

  2. Resveratrol protects vascular endothelial cells from high glucose-induced apoptosis through inhibition of NADPH oxidase activation-driven oxidative stress.

    Science.gov (United States)

    Chen, Feng; Qian, Li-Hua; Deng, Bo; Liu, Zhi-Min; Zhao, Ying; Le, Ying-Ying

    2013-09-01

    Hyperglycemia-induced oxidative stress has been implicated in diabetic vascular complications in which NADPH oxidase is a major source of reactive oxygen species (ROS) generation. Resveratrol is a naturally occurring polyphenol, which has vasoprotective effects in diabetic animal models and inhibits high glucose (HG)-induced oxidative stress in endothelial cells. We aimed to examine whether HG-induced NADPH oxidase activation and ROS production contribute to glucotoxicity to endothelial cells and the effect of resveratrol on glucotoxicity. Using a murine brain microvascular endothelial cell line bEnd3, we found that NADPH oxidase inhibitor (apocynin) and resveratrol both inhibited HG-induced endothelial cell apoptosis. HG-induced elevation of NADPH oxidase activity and production of ROS were inhibited by apocynin, suggesting that HG induces endothelial cell apoptosis through NADPH oxidase-mediated ROS production. Mechanistic studies revealed that HG upregulated NADPH oxidase subunit Nox1 but not Nox2, Nox4, and p22(phox) expression through NF-κB activation, which resulted in elevation of NADPH oxidase activity and consequent ROS production. Resveratrol prevented HG-induced endothelial cell apoptosis through inhibiting HG-induced NF-κB activation, NADPH oxidase activity elevation, and ROS production. HG induces endothelial cell apoptosis through NF-κB/NADPH oxidase/ROS pathway, which was inhibited by resveratrol. Our findings provide new potential therapeutic targets against brain vascular complications of diabetes. © 2013 John Wiley & Sons Ltd.

  3. The acute effect of coffee on endothelial function and glucose metabolism following a glucose load in healthy human volunteers.

    Science.gov (United States)

    Boon, Evan A J; Croft, Kevin D; Shinde, Sujata; Hodgson, Jonathan M; Ward, Natalie C

    2017-09-20

    A diet rich in plant polyphenols has been suggested to reduce the incidence of cardiovascular disease and type 2 diabetes mellitus, in part, via improvements in endothelial function. Coffee is a rich source of phenolic compounds including the phenolic acid, chlorogenic acid (CGA). The aim of the study was to investigate the effect of coffee as a whole beverage on endothelial function, blood pressure and blood glucose concentration. Twelve healthy men and women were recruited to a randomised, placebo-controlled, cross-over study, with three treatments tested: (i) 18 g of ground caffeinated coffee containing 300 mg CGA in 200 mL of hot water, (ii) 18 g of decaffeinated coffee containing 287 mg CGA in 200 mL of hot water, and (iii) 200 mL of hot water (control). Treatment beverages were consumed twice, two hours apart, with the second beverage consumed simultaneously with a 75 g glucose load. Blood pressure was recorded and the finger prick glucose test was performed at time = 0 and then every 30 minutes up to 2 hours. Endothelial function, assessed using flow-mediated dilatation (FMD) of the brachial artery, was measured at 1 hour and a blood sample taken at 2 hours to measure plasma nitrate/nitrite and 5-CGA concentrations. The FMD response was significantly higher in the caffeinated coffee group compared to both decaffeinated coffee and water groups (P coffee and water. Blood glucose concentrations and blood pressure were not different between the three treatment groups. In conclusion, the consumption of caffeinated coffee resulted in a significant improvement in endothelial function, but there was no evidence for benefit regarding glucose metabolism or blood pressure. Although the mechanism has yet to be elucidated the results suggest that coffee as a whole beverage may improve endothelial function, or that caffeine is the component of coffee responsible for improving FMD.

  4. Brazilin Ameliorates High Glucose-Induced Vascular Inflammation via Inhibiting ROS and CAMs Production in Human Umbilical Vein Endothelial Cells

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    Thanasekaran Jayakumar

    2014-01-01

    Full Text Available Vascular inflammatory process has been suggested to play a key role in the initiation and progression of atherosclerosis, a major complication of diabetes mellitus. Recent studies have shown that brazilin exhibits antihepatotoxic, antiplatelet, cancer preventive, or anti-inflammatory properties. Thus, we investigated whether brazilin suppresses vascular inflammatory process induced by high glucose (HG in cultured human umbilical vein endothelial cells (HUVEC. HG induced nitrite production, lipid peroxidation, and intracellular reactive oxygen species formation in HUVEC cells, which was reversed by brazilin. Western blot analysis revealed that brazilin markedly inhibited HG-induced phosphorylation of endothelial nitric oxide synthase. Besides, we investigated the effects of brazilin on the MAPK signal transduction pathway because MAPK families are associated with vascular inflammation under stress. Brazilin blocked HG-induced phosphorylation of extracellular signal-regulated kinase and transcription factor NF-κB. Furthermore, brazilin concentration-dependently attenuated cell adhesion molecules (ICAM-1 and VCAM-1 expression induced by various concentrations of HG in HUVEC. Taken together, the present data suggested that brazilin could suppress high glucose-induced vascular inflammatory process, which may be closely related with the inhibition of oxidative stress, CAMs expression, and NF-κB activation in HUVEC. Our findings may highlight a new therapeutic intervention for the prevention of vascular diseases.

  5. Endothelial HIF-1α Enables Hypothalamic Glucose Uptake to Drive POMC Neurons.

    Science.gov (United States)

    Varela, Luis; Suyama, Shigetomo; Huang, Yan; Shanabrough, Marya; Tschöp, Matthias H; Gao, Xiao-Bing; Giordano, Frank J; Horvath, Tamas L

    2017-06-01

    Glucose is the primary driver of hypothalamic proopiomelanocortin (POMC) neurons. We show that endothelial hypoxia-inducible factor 1α (HIF-1α) controls glucose uptake in the hypothalamus and that it is upregulated in conditions of undernourishment, during which POMC neuronal activity is decreased. Endothelium-specific knockdown of HIF-1α impairs the ability of POMC neurons to adapt to the changing metabolic environment in vivo, resulting in overeating after food deprivation in mice. The impaired functioning of POMC neurons was reversed ex vivo or by parenchymal glucose administration. These observations indicate an active role for endothelial cells in the central control of metabolism and suggest that central vascular impairments may cause metabolic disorders. © 2017 by the American Diabetes Association.

  6. Chronic exposure to high glucose impairs bradykinin-stimulated nitric oxide production by interfering with the phospholipase-C-implicated signalling pathway in endothelial cells: evidence for the involvement of protein kinase C.

    Science.gov (United States)

    Tang, Y; Li, G D

    2004-12-01

    Overwhelming evidence indicates that endothelial cell dysfunction in diabetes is characterised by diminished endothelium-dependent relaxation, but the matter of the underlying molecular mechanism remains unclear. As nitric oxide (NO) production from the endothelium is the major player in endothelium-mediated vascular relaxation, we investigated the effects of high glucose on NO production, and the possible alterations of signalling pathways implicated in this scenario. NO production and intracellular Ca(2+) levels ([Ca(2+)](i)) were assessed using the fluorescent probes 4,5-diaminofluorescein diacetate and fura-2 respectively. Exposure of cultured bovine aortic endothelial cells to high glucose for 5 or 10 days significantly reduced NO production induced by bradykinin (but not by Ca(2+) ionophore) in a time- and dose-dependent manner. This was probably due to an attenuation in bradykinin-induced elevations of [Ca(2+)](i) under these conditions, since a close correlation between [Ca(2+)](i) increases and NO generation was observed in intact bovine aortic endothelial cells. Both bradykinin-promoted intracellular Ca(2+) mobilisation and extracellular Ca(2+) entry were affected. Moreover, bradykinin-induced formation of Ins(1,4,5)P(3), a phospholipase C product leading to increases in [Ca(2+)](i), was also inhibited following high glucose culture. This abnormality was not attributable to a decrease in inositol phospholipids, but possibly to a reduction in the number of bradykinin receptors. The alterations in NO production, the increases in [Ca(2+)](i), and the bradykinin receptor number due to high glucose could be largely reversed by protein kinase C inhibitors and D: -alpha-tocopherol (antioxidant). Chronic exposure to high glucose reduces NO generation in endothelial cells, probably by impairing phospholipase-C-mediated Ca(2+) signalling due to excess protein kinase C activation. This defect in NO release may contribute to the diminished endothelium

  7. Effects of α-lipoic acid on endothelial function in aged diabetic and high-fat fed rats

    Science.gov (United States)

    Sena, C M; Nunes, E; Louro, T; Proença, T; Fernandes, R; Boarder, M R; Seiça, R M

    2007-01-01

    Background and purpose: This study was conducted to investigate the effects of α-lipoic acid (α-LA) on endothelial function in diabetic and high-fat fed animal models and elucidate the potential mechanism underlying the benefits of α-LA. Experimental approach: Plasma metabolites reflecting glucose and lipid metabolism, endothelial function, urinary albumin excretion (UAE), plasma and aortic malondialdehyde (MDA) and urinary 8-hydroxydeoxyguanosine (8-OHdG) were assessed in non-diabetic controls (Wistar rats), untreated Goto-Kakizaki (GK) diabetic and high-fat fed GK rats (fed with atherogenic diet only, treated with α-LA and treated with vehicle, for 3 months). Vascular eNOS, nitrotyrosine, carbonyl groups and superoxide anion were also assessed in the different groups. Key results: α-LA and soybean oil significantly reduced both total and non-HDL serum cholesterol and triglycerides induced by atherogenic diet. MDA, carbonyl groups, vascular superoxide and 8-OHdG levels were higher in GK and high-fat fed GK groups and fully reversed with α-LA treatment. High-fat fed GK diabetic rats showed significantly reduced endothelial function and increased UAE, effects ameliorated with α-LA. This endothelial dysfunction was associated with decreased NO production, decreased expression of eNOS and increased vascular superoxide production and nitrotyrosine expression. Conclusions and implications: α-LA restores endothelial function and significantly improves systemic and local oxidative stress in high-fat fed GK diabetic rats. Improved endothelial function due to α-LA was at least partially attributed to recoupling of eNOS and increased NO bioavailability and represents a pharmacological approach to prevent major complications associated with type 2 diabetes. PMID:17906683

  8. Polyphenol fraction of extra virgin olive oil protects against endothelial dysfunction induced by high glucose and free fatty acids through modulation of nitric oxide and endothelin-1

    Directory of Open Access Journals (Sweden)

    Carolina Emilia Storniolo

    2014-01-01

    Full Text Available Epidemiological and clinical studies have reported that olive oil reduces the incidence of cardiovascular disease. However, the mechanisms involved in this beneficial effect have not been delineated. The endothelium plays an important role in blood pressure regulation through the release of potent vasodilator and vasoconstrictor agents such as nitric oxide (NO and endothelin-1 (ET-1, respectively, events that are disrupted in type 2 diabetes. Extra virgin olive oil contains polyphenols, compounds that exert a biological action on endothelial function. This study analyzes the effects of olive oil polyphenols on endothelial dysfunction using an in vitro model that simulates the conditions of type 2 diabetes. Our findings show that high glucose and linoleic and oleic acids decrease endothelial NO synthase phosphorylation, and consequently intracellular NO levels, and increase ET-1 synthesis by ECV304 cells. These effects may be related to the stimulation of reactive oxygen species production in these experimental conditions. Hydroxytyrosol and the polyphenol extract from extra virgin olive oil partially reversed the above events. Moreover, we observed that high glucose and free fatty acids reduced NO and increased ET-1 levels induced by acetylcholine through the modulation of intracellular calcium concentrations and endothelial NO synthase phosphorylation, events also reverted by hydroxytyrosol and polyphenol extract. Thus, our results suggest a protective effect of olive oil polyphenols on endothelial dysfunction induced by hyperglycemia and free fatty acids.

  9. Impairment of brain endothelial glucose transporter by methamphetamine causes blood-brain barrier dysfunction

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    Murrin L Charles

    2011-03-01

    Full Text Available Abstract Background Methamphetamine (METH, an addictive psycho-stimulant drug with euphoric effect is known to cause neurotoxicity due to oxidative stress, dopamine accumulation and glial cell activation. Here we hypothesized that METH-induced interference of glucose uptake and transport at the endothelium can disrupt the energy requirement of the blood-brain barrier (BBB function and integrity. We undertake this study because there is no report of METH effects on glucose uptake and transport across the blood-brain barrier (BBB to date. Results In this study, we demonstrate that METH-induced disruption of glucose uptake by endothelium lead to BBB dysfunction. Our data indicate that a low concentration of METH (20 μM increased the expression of glucose transporter protein-1 (GLUT1 in primary human brain endothelial cell (hBEC, main component of BBB without affecting the glucose uptake. A high concentration of 200 μM of METH decreased both the glucose uptake and GLUT1 protein levels in hBEC culture. Transcription process appeared to regulate the changes in METH-induced GLUT1 expression. METH-induced decrease in GLUT1 protein level was associated with reduction in BBB tight junction protein occludin and zonula occludens-1. Functional assessment of the trans-endothelial electrical resistance of the cell monolayers and permeability of dye tracers in animal model validated the pharmacokinetics and molecular findings that inhibition of glucose uptake by GLUT1 inhibitor cytochalasin B (CB aggravated the METH-induced disruption of the BBB integrity. Application of acetyl-L-carnitine suppressed the effects of METH on glucose uptake and BBB function. Conclusion Our findings suggest that impairment of GLUT1 at the brain endothelium by METH may contribute to energy-associated disruption of tight junction assembly and loss of BBB integrity.

  10. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... symptoms include the following: High blood glucose High levels of sugar in the urine Frequent urination Increased ... you should check and what your blood glucose levels should be. Checking your blood and then treating ...

  11. N-acetylcysteine is able to reduce the oxidation status and the endothelial activation after a high-glucose content meal in patients with Type 2 diabetes mellitus.

    Science.gov (United States)

    Masha, A; Brocato, L; Dinatale, S; Mascia, C; Biasi, F; Martina, V

    2009-04-01

    Post-prandial hyperglycemia seems to play a pivotal role in the pathogenesis of the cardiovascular complications of diabetes mellitus, as it leads to an oxidative stress which in turn causes a reduced NO bioavailability. These conditions produce an endothelial activation. The aim of this study was to assure that the administration of N-acetylcysteine (NAC), thiolic antioxidant, is able to decrease the oxidation status and endothelial activation after a high-glucose content meal. Ten patients with Type 2 diabetes mellitus (DMT2) (Group 1) and 10 normal subjects (Group 2) were studied. They assumed a high-glucose content meal without (phase A) or after (phase B) the administration of NAC. Glycemia, insulinemia, intercellular adhesion molecule 1, vascular adhesion molecule 1 (VCAM-1), E-selectin, malonaldehyde (MDA), and 4-hydroxynonenal (HNE) were assessed at -30, 0, +30, +60, +90, +120, and +180 min with respect to the meal consumption. During the phase A in Group 1, only HNE and MDA levels increased after the meal assumption; all parameters remained unchanged in Group 2. During the phase B, in Group 1, HNE, MDA, VCAM-1, and E-selectin levels after the meal were lower than those in phase A, while no change for all variables were observed in Group 2. A high-glucose meal produces an increase in oxidation parameters in patients with DMT2. The administration of NAC reduces the oxidative stress and, by doing so, reduces the endothelial activation. In conclusion, NAC could be efficacious in the slackening of the progression of vascular damage in DMT2.

  12. 1,4-Anhydro-4-seleno-d-talitol (SeTal) protects endothelial function in the mouse aorta by scavenging superoxide radicals under conditions of acute oxidative stress

    DEFF Research Database (Denmark)

    Ng, Hooi Hooi; Leo, Chen Huei; O'Sullivan, Kelly

    2017-01-01

    and decreased basal nitric oxide (NO) availability. SeTal (1mM) co-treatment prevented high glucose-induced endothelial dysfunction and oxidative stress in the mouse aorta. The presence of a cyclooxygenase inhibitor, indomethacin significantly improved the sensitivity to ACh in high glucose-treated aortae......, but had no effect in SeTal-treated aortae. Our data show that SeTal has potent antioxidant activity in isolated mouse aortae and prevents high glucose-induced endothelial dysfunction by decreasing superoxide levels, increasing basal NO availability and normalising the contribution of vasoconstrictor......Hyperglycaemia increases the generation of reactive oxidants in blood vessels and is a major cause of endothelial dysfunction. A water-soluble selenium-containing sugar (1,4-Anhydro-4-seleno-d-talitol, SeTal) has potent antioxidant activity in vitro and is a promising treatment to accelerate wound...

  13. Polydatin Restores Endothelium-Dependent Relaxation in Rat Aorta Rings Impaired by High Glucose: A Novel Insight into the PPARβ-NO Signaling Pathway.

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    Yang Wu

    Full Text Available Polydatin, a natural component from Polygonum Cuspidatum, has important therapeutic effects on metabolic syndrome. A novel therapeutic strategy using polydatin to improve vascular function has recently been proposed to treat diabetes-related cardiovascular complications. However, the biological role and molecular basis of polydatin's action on vascular endothelial cells (VECs-mediated vasodilatation under diabetes-related hyperglycemia condition remain elusive. The present study aimed to assess the contribution of polydatin in restoring endothelium-dependent relaxation and to determine the details of its underlying mechanism. By measuring endothelium-dependent relaxation, we found that acetylcholine-induced vasodilation was impaired by elevated glucose (55 mmol/L; however, polydatin (1, 3, 10 μmol/L could restore the relaxation in a dose-dependent manner. Polydatin could also improve the histological damage to endothelial cells in the thoracic aorta. Polydatin's effects were mediated via promoting the expression of endothelial NO synthase (eNOS, enhancing eNOS activity and decreasing the inducible NOS (iNOS level, finally resulting in a beneficial increase in NO release, which probably, at least in part, through activation of the PPARβ signaling pathway. The results provided a novel insight into polydatin action, via PPARβ-NO signaling pathways, in restoring endothelial function in high glucose conditions. The results also indicated the potential utility of polydatin to treat diabetes related cardiovascular diseases.

  14. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... your blood and then treating high blood glucose early will help you avoid problems associated with hyperglycemia. ... to detect hyperglycemia so you can treat it early — before it gets worse. If you're new ...

  15. Glucose-Treated Manganese Hexacyanoferrate for Sodium-Ion Secondary Battery

    OpenAIRE

    Moritomo, Yutaka; Goto, Kensuke; Shibata, Takayuki

    2015-01-01

    Manganese hexacyanoferrate (Mn-PBA) is a promising cathode material forsodium-ion secondary battery (SIB) with high average voltage (=3.4 V) against Na. Here,we find that the thermal decomposition of glucose modifies the surface state of Mn-PBA,without affecting the bulk crystal structure. The glucose treatment significantly improves therate properties of Mn-PBA in SIB. The critical discharge rate increases from 1 C (as-grown)to 15 C (glucose-treated). Our observation suggests that thermal tr...

  16. Glucose-Treated Manganese Hexacyanoferrate for Sodium-Ion Secondary Battery

    Directory of Open Access Journals (Sweden)

    Yutaka Moritomo

    2015-09-01

    Full Text Available Manganese hexacyanoferrate (Mn-PBA is a promising cathode material forsodium-ion secondary battery (SIB with high average voltage (=3.4 V against Na. Here,we find that the thermal decomposition of glucose modifies the surface state of Mn-PBA,without affecting the bulk crystal structure. The glucose treatment significantly improves therate properties of Mn-PBA in SIB. The critical discharge rate increases from 1 C (as-grownto 15 C (glucose-treated. Our observation suggests that thermal treatment is quite effectivefor insulating coordination polymers.

  17. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... how often you should check and what your blood glucose levels should be. Checking your blood and then treating ... I Treat Hyperglycemia? You can often lower your blood glucose level by exercising. However, if your blood glucose is ...

  18. Carbohydrate-Restriction with High-Intensity Interval Training: An Optimal Combination for Treating Metabolic Diseases?

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    Monique E. Francois

    2017-10-01

    Full Text Available Lifestyle interventions incorporating both diet and exercise strategies remain cornerstone therapies for treating metabolic disease. Carbohydrate-restriction and high-intensity interval training (HIIT have independently been shown to improve cardiovascular and metabolic health. Carbohydrate-restriction reduces postprandial hyperglycemia, thereby limiting potential deleterious metabolic and cardiovascular consequences of excessive glucose excursions. Additionally, carbohydrate-restriction has been shown to improve body composition and blood lipids. The benefits of exercise for improving insulin sensitivity are well known. In this regard, HIIT has been shown to rapidly improve glucose control, endothelial function, and cardiorespiratory fitness. Here, we report the available evidence for each strategy and speculate that the combination of carbohydrate-restriction and HIIT will synergistically maximize the benefits of both approaches. We hypothesize that this lifestyle strategy represents an optimal intervention to treat metabolic disease; however, further research is warranted in order to harness the potential benefits of carbohydrate-restriction and HIIT for improving cardiometabolic health.

  19. Carbohydrate-Restriction with High-Intensity Interval Training: An Optimal Combination for Treating Metabolic Diseases?

    Science.gov (United States)

    Francois, Monique E; Gillen, Jenna B; Little, Jonathan P

    2017-01-01

    Lifestyle interventions incorporating both diet and exercise strategies remain cornerstone therapies for treating metabolic disease. Carbohydrate-restriction and high-intensity interval training (HIIT) have independently been shown to improve cardiovascular and metabolic health. Carbohydrate-restriction reduces postprandial hyperglycemia, thereby limiting potential deleterious metabolic and cardiovascular consequences of excessive glucose excursions. Additionally, carbohydrate-restriction has been shown to improve body composition and blood lipids. The benefits of exercise for improving insulin sensitivity are well known. In this regard, HIIT has been shown to rapidly improve glucose control, endothelial function, and cardiorespiratory fitness. Here, we report the available evidence for each strategy and speculate that the combination of carbohydrate-restriction and HIIT will synergistically maximize the benefits of both approaches. We hypothesize that this lifestyle strategy represents an optimal intervention to treat metabolic disease; however, further research is warranted in order to harness the potential benefits of carbohydrate-restriction and HIIT for improving cardiometabolic health.

  20. Multi-targeted mechanisms underlying the endothelial protective effects of the diabetic-safe sweetener erythritol.

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    Daniëlle M P H J Boesten

    Full Text Available Diabetes is characterized by hyperglycemia and development of vascular pathology. Endothelial cell dysfunction is a starting point for pathogenesis of vascular complications in diabetes. We previously showed the polyol erythritol to be a hydroxyl radical scavenger preventing endothelial cell dysfunction onset in diabetic rats. To unravel mechanisms, other than scavenging of radicals, by which erythritol mediates this protective effect, we evaluated effects of erythritol in endothelial cells exposed to normal (7 mM and high glucose (30 mM or diabetic stressors (e.g. SIN-1 using targeted and transcriptomic approaches. This study demonstrates that erythritol (i.e. under non-diabetic conditions has minimal effects on endothelial cells. However, under hyperglycemic conditions erythritol protected endothelial cells against cell death induced by diabetic stressors (i.e. high glucose and peroxynitrite. Also a number of harmful effects caused by high glucose, e.g. increased nitric oxide release, are reversed. Additionally, total transcriptome analysis indicated that biological processes which are differentially regulated due to high glucose are corrected by erythritol. We conclude that erythritol protects endothelial cells during high glucose conditions via effects on multiple targets. Overall, these data indicate a therapeutically important endothelial protective effect of erythritol under hyperglycemic conditions.

  1. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... breast cancer and AIDS combined. Your gift today will help us get closer to curing diabetes and ... blood and then treating high blood glucose early will help you avoid problems associated with hyperglycemia. How ...

  2. MicroRNA-134 Contributes to Glucose-Induced Endothelial Cell Dysfunction and This Effect Can Be Reversed by Far-Infrared Irradiation.

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    Hsei-Wei Wang

    Full Text Available Diabetes mellitus (DM is a metabolic disease that is increasing worldwide. Furthermore, it is associated with the deregulation of vascular-related functions, which can develop into major complications among DM patients. Endothelial colony forming cells (ECFCs have the potential to bring about medical repairs because of their post-natal angiogenic activities; however, such activities are impaired by high glucose- (HG and the DM-associated conditions. Far-infrared radiation (FIR transfers energy as heat that is perceived by the thermoreceptors in human skin. Several studies have revealed that FIR improves vascular endothelial functioning and boost angiogenesis. FIR has been used as anti-inflammatory therapy and as a clinical treatment for peripheral circulation improvement. In addition to vascular repair, there is increasing evidence to show that FIR can be applied to a variety of diseases, including cardiovascular disorders, hypertension and arthritis. Yet mechanism of action of FIR and the biomarkers that indicate FIR effects remain unclear. MicroRNA-134 (miR-134-5p was identified by small RNA sequencing as being increased in high glucose (HG treated dfECFCs (HG-dfECFCs. Highly expressed miR-134 was also validated in dmECFCs by RT-qPCR and it is associated with impaired angiogenic activities of ECFCs. The functioning of ECFCs is improved by FIR treatment and this occurs via a reduction in the level of miR-134 and an increase in the NRIP1 transcript, a direct target of miR-134. Using a mouse ischemic hindlimb model, the recovery of impaired blood flow in the presence of HG-dfECFCs was improved by FIR pretreatment and this enhanced functionality was decreased when there was miR-134 overexpression in the FIR pretreated HG-dfECFCs. In conclusion, our results reveal that the deregulation of miR-134 is involved in angiogenic defects found in DM patients. FIR treatment improves the angiogenic activity of HG-dfECFCs and dmECFCs and FIR has potential as

  3. Effects of High Glucose on Vascular Endothelial Growth Factor Synthesis and Secretion in Aortic Vascular Smooth Muscle Cells from Obese and Lean Zucker Rats

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    Mariella Trovati

    2012-07-01

    Full Text Available Type 1 diabetes is characterized by insulin deficiency, type 2 by both insulin deficiency and insulin resistance: in both conditions, hyperglycaemia is accompanied by an increased cardiovascular risk, due to increased atherosclerotic plaque formation/instabilization and impaired collateral vessel formation. An important factor in these phenomena is the Vascular Endothelial Growth Factor (VEGF, a molecule produced also by Vascular Smooth Muscle Cells (VSMC. We aimed at evaluating the role of high glucose on VEGF-A164 synthesis and secretion in VSMC from lean insulin-sensitive and obese insulin-resistant Zucker rats (LZR and OZR. In cultured aortic VSMC from LZR and OZR incubated for 24 h with D-glucose (5.5, 15 and 25 mM or with the osmotic controls L-glucose and mannitol, we measured VEGF-A164 synthesis (western, blotting and secretion (western blotting and ELISA. We observed that: (i D-glucose dose-dependently increases VEGF-A164 synthesis and secretion in VSMC from LZR and OZR (n = 6, ANOVA p = 0.002–0.0001; (ii all the effects of 15 and 25 mM D-glucose are attenuated in VSMC from OZR vs. LZR (p = 0.0001; (iii L-glucose and mannitol reproduce the VEGF-A164 modulation induced by D-glucose in VSMC from both LZR and OZR. Thus, glucose increases via an osmotic mechanism VEGF synthesis and secretion in VSMC, an effect attenuated in the presence of insulin resistance.

  4. Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in high glucose treated human mesangial cells

    International Nuclear Information System (INIS)

    Li, Yang; Hu, Fang; Xue, Meng; Jia, Yi-Jie; Zheng, Zong-Ji; Wang, Ling; Guan, Mei-Ping; Xue, Yao-Ming

    2017-01-01

    Diabetic kidney disease (DKD) has become the leading cause of end-stage renal disease worldwide and is associated with glomerular mesangial cell (MC) proliferation and excessive extracellular matrix (ECM) production. Klotho can attenuate renal fibrosis in part by inhibiting TGF-β1/Smad3 signaling in DKD. Early growth response factor 1 (Egr-1) has been shown to play a key role in renal fibrosis in part by facilitating the formation of a positive feedback loop involving TGF-β1. However, whether Klotho down-regulates Egr-1 by inhibiting TGF-β1/Smad3 signaling in DKD is unclear. In the present study, we assessed human MCs that were incubated under high-glucose conditions to mimic diabetes. Then, we transfected the cells with Klotho plasmid or siRNA to overexpress or knock down Klotho gene and protein expression. Klotho, Egr-1, fibronectin (FN), collagen type I (Col I), Smad3 and phosphorylated Smad3 (p-Smad3) gene and protein expression levels were determined by RT-qPCR and western blotting respectively. High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. pcDNA3.1-Klotho transfection-mediated Klotho overexpression down-regulated Egr-1, FN and Col I expression and the p-Smad3/Smad3 ratio in human MCs. Conversely, siRNA-mediated Klotho silencing up-regulated Egr-1, FN, and Col I expression and the p-Smad3/Smad3 ratio. Moreover, the effects of si-Klotho on Egr-1 expression were abolished by the TGF-β1 inhibitor SB-431542. Klotho overexpression can prevent mesangial ECM production in high-glucose-treated human MCs, an effect that has been partially attributed to Egr-1 down-regulation facilitated by TGF-β1/Smad3 signaling inhibition. - Highlights: • High glucose time-dependently down-regulated Klotho mRNA and protein expression in cultured human MCs. • Klotho overexpression down-regulated Egr-1 and prevented mesangial ECM production in high-glucose-treated human MCs. • Klotho down-regulated Egr-1 by inhibiting

  5. Treating fat grafts with human endothelial progenitor cells promotes their vascularization and improves their survival in diabetes mellitus.

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    Hamed, Saher; Ben-Nun, Ohad; Egozi, Dana; Keren, Aviad; Malyarova, Nastya; Kruchevsky, Danny; Gilhar, Amos; Ullmann, Yehuda

    2012-10-01

    Bone marrow-derived endothelial progenitor cells are required for vascularization of a fat graft to form a functional microvasculature within the graft and to facilitate its integration into the surrounding tissues. Organ transplantation carries a high risk of graft loss and rejection in patients with diabetes mellitus because endothelial progenitor cell function is impaired. The authors investigated the influence of endothelial progenitor cell treatment on the phenotype and survival of human fat grafts in immunocompromised mice with experimentally induced diabetes mellitus. The authors injected 1 ml of human fat tissue into the scalps of 14 nondiabetic and 28 diabetic immunocompromised mice, and then treated some of the grafts with endothelial progenitor cells that was isolated from the blood of a human donor. The phenotype of the endothelial progenitor cell-treated fat grafts from the 14 diabetic mice was compared with that of the untreated fat grafts from 14 nondiabetic and 14 diabetic mice, 18 days and 15 weeks after fat transplantation. Determination of graft phenotype included measurements of weight and volume, vascular endothelial growth factor levels, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and caspase 3 expression levels, and histologic analysis of the extent of vascularization. The untreated grafts from the diabetic mice were fully resorbed 15 weeks after fat transplantation. The phenotype of endothelial progenitor cell-treated fat grafts from the diabetic mice was similar to that of the untreated fat grafts from the nondiabetic mice. Endothelial progenitor cell treatment of transplanted fat can increase the survival of a fat graft by inducing its vascularization and decreasing the extent of apoptosis.

  6. Sinomenine alleviates high glucose-induced renal glomerular endothelial hyperpermeability by inhibiting the activation of RhoA/ROCK signaling pathway

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    Yin, Qingqiao [Renal Department of Internal Medicine, The Third Hospital of Wuhan (China); Xia, Yuanyu, E-mail: xiayuanyu.wh@gmail.com [Renal Department of Internal Medicine, The Third Hospital of Wuhan (China); Wang, Guan [Department of Cardiology, The Second Affiliated Hospital of Guangzhou Medical University (China)

    2016-09-02

    As an early sign of diabetic cardiovascular disease, endothelial dysfunction may contribute to progressive diabetic nephropathy (DN). Endothelial hyperpermeability induced by hyperglycemia (HG) is a central pathogenesis for DN. Sinomenine (SIN) has strong anti-inflammatory and renal protective effects, following an unknown protective mechanism against HG-induced hyperpermeability. We herein explored the role of SIN in vitro in an HG-induced barrier dysfunction model in human renal glomerular endothelial cells (HRGECs). The cells were exposed to SIN and/or HG for 24 h, the permeability of which was significantly increased by HG. Moreover, junction protein occludin in the cell-cell junction area and its total expression in HRGECs were significantly decreased by HG. However, the dysfunction of tight junction and hyperpermeability of HRGECs were significantly reversed by SIN. Furthermore, SIN prevented HG-increased reactive oxygen species (ROS) by activating nuclear factor-E2-related factor 2 (Nrf2). Interestingly, activation of RhoA/ROCK induced by HG was reversed by SIN or ROCK inhibitor. HG-induced hyperpermeability was prevented by SIN. High ROS level, tight junction dysfunction and RhoA/ROCK activation were significantly attenuated with knockdown of Nrf2. Mediated by activation of Nrf2, SIN managed to significantly prevent HG-disrupted renal endothelial barrier function by suppressing the RhoA/ROCK signaling pathway through reducing ROS. We successfully identified a novel pathway via which SIN exerted antioxidative and renal protective functions, and provided a molecular basis for potential SIN applications in treating DN vascular disorders.

  7. Sinomenine alleviates high glucose-induced renal glomerular endothelial hyperpermeability by inhibiting the activation of RhoA/ROCK signaling pathway.

    Science.gov (United States)

    Yin, Qingqiao; Xia, Yuanyu; Wang, Guan

    2016-09-02

    As an early sign of diabetic cardiovascular disease, endothelial dysfunction may contribute to progressive diabetic nephropathy (DN). Endothelial hyperpermeability induced by hyperglycemia (HG) is a central pathogenesis for DN. Sinomenine (SIN) has strong anti-inflammatory and renal protective effects, following an unknown protective mechanism against HG-induced hyperpermeability. We herein explored the role of SIN in vitro in an HG-induced barrier dysfunction model in human renal glomerular endothelial cells (HRGECs). The cells were exposed to SIN and/or HG for 24 h, the permeability of which was significantly increased by HG. Moreover, junction protein occludin in the cell-cell junction area and its total expression in HRGECs were significantly decreased by HG. However, the dysfunction of tight junction and hyperpermeability of HRGECs were significantly reversed by SIN. Furthermore, SIN prevented HG-increased reactive oxygen species (ROS) by activating nuclear factor-E2-related factor 2 (Nrf2). Interestingly, activation of RhoA/ROCK induced by HG was reversed by SIN or ROCK inhibitor. HG-induced hyperpermeability was prevented by SIN. High ROS level, tight junction dysfunction and RhoA/ROCK activation were significantly attenuated with knockdown of Nrf2. Mediated by activation of Nrf2, SIN managed to significantly prevent HG-disrupted renal endothelial barrier function by suppressing the RhoA/ROCK signaling pathway through reducing ROS. We successfully identified a novel pathway via which SIN exerted antioxidative and renal protective functions, and provided a molecular basis for potential SIN applications in treating DN vascular disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Glucose-independent persistence of PAI-1 gene expression and H3K4 tri-methylation in type 1 diabetic mouse endothelium: implication in metabolic memory.

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    Takizawa, Fumihiko; Mizutani, Shuki; Ogawa, Yoshihiro; Sawada, Naoki

    2013-03-29

    Clinical trials with type 1 and type 2 diabetes have identified a phenomenon known as "metabolic memory" in which previous periods of hyperglycemia result in the long-lasting deleterious impact on cardiovascular events. Emerging evidence shows that transient hyperglycemic exposure of human endothelial cells induces histone 3 lysine 4 mono-methylation (H3K4me1) on the promoter and persistent mRNA expression of RelA and IL-8 genes, suggesting that epigenetic histone modification and chromatin structure remodeling is a key event underlying metabolic memory. This burgeoning hypothesis, however, critically remains to be tested for relevance in the disease process of diabetes in vivo, and for broader applicability to an array of genes involved in endothelial dysfunction. To address this, we used type 1 diabetes mouse model induced by streptozocin to be hyperglycemic for 8 weeks, and isolated endothelial cells that were used either freshly after isolation or after 2 to 3-week cell culture in normoglycemic conditions. mRNA expression profiling in diabetic mouse endothelial cells revealed significant and persistent up-regulation of Serpine1 encoding PAI-1, the hypo-fibrinolytic mediator leading to thrombotic diseases in diabetes, along with Rock2, Fn1 and Ccl2, whereas only Serpine 1 was persistently elevated in high glucose-treated mouse endothelial cells. Chromosome immunoprecipitation assay in type 1 diabetic mouse endothelial cells showed predominant enrichment of H3K4 tri-methylation on Serpine1 promoter, suggesting a unique epigenetic regulation in diabetic mice as opposed to high glucose-treated human ECs. Our study demonstrates the importance of combining in vivo models of diabetes with high glucose-treated cell culture to better assess the epigenetic mechanisms relevant to disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Roles of p300 and cyclic adenosine monophosphate response element binding protein in high glucose-induced hypoxia-inducible factor 1α inactivation under hypoxic conditions.

    Science.gov (United States)

    Ding, Lingtao; Yang, Minlie; Zhao, Tianlan; Lv, Guozhong

    2017-05-01

    Given the high prevalence of diabetes and burn injuries worldwide, it is essential to dissect the underlying mechanism of delayed burn wound healing in diabetes patients, especially the high glucose-induced hypoxia-inducible factor 1 (HIF-1)-mediated transcription defects. Human umbilical vein endothelial cells were cultured with low or high concentrations of glucose. HIF-1α-induced vascular endothelial growth factor (VEGF) transcription was measured by luciferase assay. Immunofluorescence staining was carried out to visualize cyclic adenosine monophosphate response element binding protein (CREB) localization. Immunoprecipitation was carried out to characterize the association between HIF-1α/p300/CREB. To test whether p300, CREB or p300+CREB co-overexpression was sufficient to rescue the HIF-1-mediated transcription defect after high glucose exposure, p300, CREB or p300+CREB co-overexpression were engineered, and VEGF expression was quantified. Finally, in vitro angiogenesis assay was carried out to test whether the high glucose-induced angiogenesis defect is rescuable by p300 and CREB co-overexpression. Chronic high glucose treatment resulted in impaired HIF-1-induced VEGF transcription and CREB exclusion from the nucleus. P300 or CREB overexpression alone cannot rescue high glucose-induced HIF-1α transcription defects. In contrast, co-overexpression of p300 and CREB dramatically ameliorated high glucose-induced impairment of HIF-1-mediated VEGF transcription, as well as in vitro angiogenesis. Finally, we showed that co-overexpression of p300 and CREB rectifies the dissociation of HIF-1α-p300-CREB protein complex in chronic high glucose-treated cells. Both p300 and CREB are required for the function integrity of HIF-1α transcription machinery and subsequent angiogenesis, suggesting future studies to improve burn wound healing might be directed to optimization of the interaction between p300, CREB and HIF-1α. © 2016 The Authors. Journal of Diabetes

  10. Inflammation determines the pro-adhesive properties of high extracellular d-glucose in human endothelial cells in vitro and rat microvessels in vivo.

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    Verónica Azcutia

    Full Text Available BACKGROUND: Hyperglycemia is acknowledged as an independent risk factor for developing diabetes-associated atherosclerosis. At present, most therapeutic approaches are targeted at a tight glycemic control in diabetic patients, although this fails to prevent macrovascular complications of the disease. Indeed, it remains highly controversial whether or not the mere elevation of extracellular D-glucose can directly promote vascular inflammation, which favors early pro-atherosclerotic events. METHODS AND FINDINGS: In the present work, increasing extracellular D-glucose from 5.5 to 22 mmol/L was neither sufficient to induce intercellular adhesion molecule-1 (ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1 expression, analyzed by flow cytometry, nor to promote leukocyte adhesion to human umbilical vein endothelial cells (HUVEC in vitro, measured by flow chamber assays. Interestingly, the elevation of D-glucose levels potentiated ICAM-1 and VCAM-1 expression and leukocyte adhesion induced by a pro-inflammatory stimulus, such as interleukin (IL-1beta (5 ng/mL. In HUVEC, high D-glucose augmented the activation of extracellular signal-regulated kinase 1/2 (ERK 1/2 and nuclear transcription factor-kappaB (NF-kappaB elicited by IL-1beta, measured by Western blot and electromobility shift assay (EMSA, respectively, but had no effect by itself. Both ERK 1/2 and NF-kappaB were necessary for VCAM-1 expression, but not for ICAM-1 expression. In vivo, leukocyte trafficking was evaluated in the rat mesenteric microcirculation by intravital microscopy. In accordance with the in vitro data, the acute intraperitoneal injection of D-glucose increased leukocyte rolling flux, adhesion and migration, but only when IL-1beta was co-administered. CONCLUSIONS: These results indicate that the elevation of extracellular D-glucose levels is not sufficient to promote vascular inflammation, and they highlight the pivotal role of a pro-inflammatory environment in diabetes, as

  11. Antioxidant and Anti-Inflammatory Effects of Blueberry Anthocyanins on High Glucose-Induced Human Retinal Capillary Endothelial Cells

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    Wuyang Huang

    2018-01-01

    Full Text Available Blueberries possess abundant anthocyanins, which benefit eye health. The purpose of this study was to explore the protective functional role of blueberry anthocyanin extract (BAE and its predominant constituents, malvidin (Mv, malvidin-3-glucoside (Mv-3-glc, and malvidin-3-galactoside (Mv-3-gal, on high glucose- (HG- induced injury in human retinal capillary endothelial cells (HRCECs. The results showed that BAE, Mv, Mv-3-glc, and Mv-3-gal enhanced cell viability (P<0.05 versus the HG group at 24 h; decreased the reactive oxygen species (ROS, P<0.01 versus the HG group both at 24 and 48 h; and increased the enzyme activity of catalase (CAT and superoxide dismutase (SOD (P<0.05 versus the HG group both at 24 and 48 h. Mv could greatly inhibit HG-induced Nox4 expression both at 24 and 48 h (P<0.05, while BAE and Mv-3-gal downregulated Nox4 only at 48 h (P<0.05. Mv, Mv-3-glc, and Mv-3-gal also changed nitric oxide (NO levels (P<0.05. BAE and Mv-3-glc also influenced angiogenesis by decreasing the vascular endothelial cell growth factor (VEGF level and inhibiting Akt pathway (P<0.05. Moreover, Mv and Mv-3-glc inhibited HG-induced intercellular adhesion molecule-1 (ICAM-1, P<0.001 and nuclear factor-kappa B (NF-κB (P<0.05. It indicated that blueberry anthocyanins protected HRCECs via antioxidant and anti-inflammatory mechanisms, which could be promising molecules for the development of nutraceuticals to prevent diabetic retinopathy.

  12. Endothelial activation and cardiometabolic profiles of treated and never-treated HIV infected Africans.

    Science.gov (United States)

    Fourie, C M T; Schutte, A E; Smith, W; Kruger, A; van Rooyen, J M

    2015-05-01

    The role the human immunodeficiency virus (HIV) and antiretroviral treatment on endothelial activation, and the subsequent relationship with cardiovascular disease, is not well understood. We investigated endothelial activation, inflammatory and cardiometabolic profiles, and measures of vascular structure and function of 66 antiretroviral treated (ART), 78 never-treated (no-ART) HIV infected and 165 HIV free Africans. Blood samples were obtained for biochemical analysis and blood pressure, pulse wave velocity (PWV) and carotid intima-media thickness (IMT) measurements were performed. The HIV infection duration was at least five years and the treatment 2.86±0.13 years. The intracellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM) levels were elevated in the HIV infected groups compared to the controls. The odds of higher adhesion molecule levels were increased when HIV infected (especially in the no-ART group); OR no-ART vs. no-HIV: ICAM 3.92 (2.2-7.0); VCAM 16.2 (7.5-35). ICAM and VCAM associated with HIV status and interleukin-6 (IL-6) in the total group (all pART: β=-0.28, p=0.01; ART: β=-0.22, p=0.07) and TC (no-ART: β=-0.36, pART: β=-0.27, p=0.03). The ART group had an unfavourable lipid profile compared to the no-ART group. The inflammatory markers (C-reactive protein (CRP) and IL-6), PWV and IMT did not differ between the three groups. HIV infected Africans showed endothelial activation when compared to HIV free controls. The endothelial activation was not accompanied by increased inflammation (as measured with CRP and IL-6), arterial stiffness or sub-clinical atherosclerosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Oxidative stress plays a role in high glucose-induced activation of pancreatic stellate cells

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    Ryu, Gyeong Ryul; Lee, Esder; Chun, Hyun-Ji; Yoon, Kun-Ho; Ko, Seung-Hyun; Ahn, Yu-Bae; Song, Ki-Ho, E-mail: kihos@catholic.ac.kr

    2013-09-20

    Highlights: •High glucose increased production of reactive oxygen species in cultured pancreatic stellate cells. •High glucose facilitated the activation of these cells. •Antioxidant treatment attenuated high glucose-induced activation of these cells. -- Abstract: The activation of pancreatic stellate cells (PSCs) is thought to be a potential mechanism underlying islet fibrosis, which may contribute to progressive β-cell failure in type 2 diabetes. Recently, we demonstrated that antioxidants reduced islet fibrosis in an animal model of type 2 diabetes. However, there is no in vitro study demonstrating that high glucose itself can induce oxidative stress in PSCs. Thus, PSCs were isolated and cultured from Sprague Dawley rats, and treated with high glucose for 72 h. High glucose increased the production of reactive oxygen species. When treated with high glucose, freshly isolated PSCs exhibited myofibroblastic transformation. During early culture (passage 1), PSCs treated with high glucose contained an increased number of α-smooth muscle actin-positive cells. During late culture (passages 2–5), PSCs treated with high glucose exhibited increases in cell proliferation, the expression of fibronectin and connective tissue growth factor, release of interleukin-6, transforming growth factor-β and collagen, and cell migration. Finally, the treatment of PSCs with high glucose and antioxidants attenuated these changes. In conclusion, we demonstrated that high glucose increased oxidative stress in primary rat PSCs, thereby facilitating the activation of these cells, while antioxidant treatment attenuated high glucose-induced PSC activation.

  14. Oxidative stress plays a role in high glucose-induced activation of pancreatic stellate cells

    International Nuclear Information System (INIS)

    Ryu, Gyeong Ryul; Lee, Esder; Chun, Hyun-Ji; Yoon, Kun-Ho; Ko, Seung-Hyun; Ahn, Yu-Bae; Song, Ki-Ho

    2013-01-01

    Highlights: •High glucose increased production of reactive oxygen species in cultured pancreatic stellate cells. •High glucose facilitated the activation of these cells. •Antioxidant treatment attenuated high glucose-induced activation of these cells. -- Abstract: The activation of pancreatic stellate cells (PSCs) is thought to be a potential mechanism underlying islet fibrosis, which may contribute to progressive β-cell failure in type 2 diabetes. Recently, we demonstrated that antioxidants reduced islet fibrosis in an animal model of type 2 diabetes. However, there is no in vitro study demonstrating that high glucose itself can induce oxidative stress in PSCs. Thus, PSCs were isolated and cultured from Sprague Dawley rats, and treated with high glucose for 72 h. High glucose increased the production of reactive oxygen species. When treated with high glucose, freshly isolated PSCs exhibited myofibroblastic transformation. During early culture (passage 1), PSCs treated with high glucose contained an increased number of α-smooth muscle actin-positive cells. During late culture (passages 2–5), PSCs treated with high glucose exhibited increases in cell proliferation, the expression of fibronectin and connective tissue growth factor, release of interleukin-6, transforming growth factor-β and collagen, and cell migration. Finally, the treatment of PSCs with high glucose and antioxidants attenuated these changes. In conclusion, we demonstrated that high glucose increased oxidative stress in primary rat PSCs, thereby facilitating the activation of these cells, while antioxidant treatment attenuated high glucose-induced PSC activation

  15. Acidic preconditioning of endothelial colony-forming cells (ECFC) promote vasculogenesis under proinflammatory and high glucose conditions in vitro and in vivo.

    Science.gov (United States)

    Mena, Hebe Agustina; Zubiry, Paula Romina; Dizier, Blandine; Schattner, Mirta; Boisson-Vidal, Catherine; Negrotto, Soledad

    2018-05-02

    We have previously demonstrated that acidic preconditioning of human endothelial colony-forming cells (ECFC) increased proliferation, migration, and tubulogenesis in vitro, and increased their regenerative potential in a murine model of hind limb ischemia without baseline disease. We now analyze whether this strategy is also effective under adverse conditions for vasculogenesis, such as the presence of ischemia-related toxic molecules or diabetes, one of the main target diseases for cell therapy due to their well-known healing impairments. Cord blood-derived CD34 + cells were seeded in endothelial growth culture medium (EGM2) and ECFC colonies were obtained after 14-21 days. ECFC were exposed at pH 6.6 (preconditioned) or pH 7.4 (nonpreconditioned) for 6 h, and then pH was restored at 7.4. A model of type 2 diabetes induced by a high-fat and high-sucrose diet was developed in nude mice and hind limb ischemia was induced in these animals by femoral artery ligation. A P value < 0.05 was considered statistically significant (by one-way analysis of variance). We found that acidic preconditioning increased ECFC adhesion and the release of pro-angiogenic molecules, and protected ECFC from the cytotoxic effects of monosodium urate crystals, histones, and tumor necrosis factor (TNF)α, which induced necrosis, pyroptosis, and apoptosis, respectively. Noncytotoxic concentrations of high glucose, TNFα, or their combination reduced ECFC proliferation, stromal cell-derived factor (SDF)1-driven migration, and tubule formation on a basement membrane matrix, whereas almost no inhibition was observed in preconditioned ECFC. In type 2 diabetic mice, intravenous administration of preconditioned ECFC significantly induced blood flow recovery at the ischemic limb as measured by Doppler, compared with the phosphate-buffered saline (PBS) and nonpreconditioned ECFC groups. Moreover, the histologic analysis of gastrocnemius muscles showed an increased vascular density and reduced

  16. 2-Deoxy-D-glucose treatment of endothelial cells induces autophagy by reactive oxygen species-mediated activation of the AMP-activated protein kinase.

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    Qilong Wang

    2011-02-01

    Full Text Available Autophagy is a cellular self-digestion process activated in response to stresses such as energy deprivation and oxidative stress. However, the mechanisms by which energy deprivation and oxidative stress trigger autophagy remain undefined. Here, we report that activation of AMP-activated protein kinase (AMPK by mitochondria-derived reactive oxygen species (ROS is required for autophagy in cultured endothelial cells. AMPK activity, ROS levels, and the markers of autophagy were monitored in confluent bovine aortic endothelial cells (BAEC treated with the glycolysis blocker 2-deoxy-D-glucose (2-DG. Treatment of BAEC with 2-DG (5 mM for 24 hours or with low concentrations of H(2O(2 (100 µM induced autophagy, including increased conversion of microtubule-associated protein light chain 3 (LC3-I to LC3-II, accumulation of GFP-tagged LC3 positive intracellular vacuoles, and increased fusion of autophagosomes with lysosomes. 2-DG-treatment also induced AMPK phosphorylation, which was blocked by either co-administration of two potent anti-oxidants (Tempol and N-Acetyl-L-cysteine or overexpression of superoxide dismutase 1 or catalase in BAEC. Further, 2-DG-induced autophagy in BAEC was blocked by overexpressing catalase or siRNA-mediated knockdown of AMPK. Finally, pretreatment of BAEC with 2-DG increased endothelial cell viability after exposure to hypoxic stress. Thus, AMPK is required for ROS-triggered autophagy in endothelial cells, which increases endothelial cell survival in response to cell stress.

  17. Gene expression profiles of glucose toxicity-exposed islet microvascular endothelial cells.

    Science.gov (United States)

    Liu, Mingming; Lu, Wenbao; Hou, Qunxing; Wang, Bing; Sheng, Youming; Wu, Qingbin; Li, Bingwei; Liu, Xueting; Zhang, Xiaoyan; Li, Ailing; Zhang, Honggang; Xiu, Ruijuan

    2018-03-25

    Islet microcirculation is mainly composed by IMECs. The aim of the study was to investigate the differences in gene expression profiles of IMECs upon glucose toxicity exposure and insulin treatment. IMECs were treated with 5.6 mmol L -1 glucose, 35 mmol L -1 glucose, and 35 mmol L -1 glucose plus 10 -8  mol L -1 insulin, respectively. Gene expression profiles were determined by microarray and verified by qPCR. GO terms and KEGG analysis were performed to assess the potential roles of differentially expressed genes. The interaction and expression tendency of differentially expressed genes were analyzed by Path-Net algorithm. Compared with glucose toxicity-exposed IMECs, 1574 mRNAs in control group and 2870 mRNAs in insulin-treated IMECs were identified with differential expression, respectively. GO and KEGG pathway analysis revealed that these genes conferred roles in regulation of apoptosis, proliferation, migration, adhesion, and metabolic process etc. Additionally, MAPK signaling pathway and apoptosis were the dominant nodes in Path-Net. IMECs survival and function pathways were significantly changed, and the expression tendency of genes from euglycemia and glucose toxicity exposure to insulin treatment was revealed and enriched in 7 patterns. Our study provides a microcirculatory framework for gene expression profiles of glucose toxicity-exposed IMECs. © 2018 John Wiley & Sons Ltd.

  18. [Circulating endothelial progenitor cell levels in treated hypertensive patients].

    Science.gov (United States)

    Maroun-Eid, C; Ortega-Hernández, A; Abad, M; García-Donaire, J A; Barbero, A; Reinares, L; Martell-Claros, N; Gómez-Garre, D

    2015-01-01

    Most optimally treated hypertensive patients still have an around 50% increased risk of any cardiovascular event, suggesting the possible existence of unidentified risk factors. In the last years there has been evidence of the essential role of circulating endothelial progenitor cells (EPCs) in the maintenance of endothelial integrity and function, increasing the interest in their involvement in cardiovascular disease. In this study, the circulating levels of EPCs and vascular endothelial growth factor (VEGF) are investigated in treated hypertensive patients with adequate control of blood pressure (BP). Blood samples were collected from treated hypertensive patients with controlled BP. Plasma levels of EPCs CD34+/KDR+ and CD34+/VE-cadherin+ were quantified by flow cytometry. Plasma concentration of VEGF was determined by ELISA. A group of healthy subjects without cardiovascular risk factors was included as controls. A total of 108 hypertensive patients were included (61±12 years, 47.2% men) of which 82.4% showed BP<140/90 mmHg, 91.7% and 81.5% controlled diabetes (HbA1c <7%) and cLDL (<130 or 100 mg/dL), respectively, and 85.2% were non-smokers. Around 45% of them were obese. Although patients had cardiovascular parameters within normal ranges, they showed significantly lower levels of CD34+/KDR+ and CD34+/VE-cadherin+ compared with healthy control group, although plasma VEGF concentration was higher in patients than in controls. Despite an optimal treatment, hypertensive patients show a decreased number of circulating EPCs that could be, at least in part, responsible for their residual cardiovascular risk, suggesting that these cells could be a therapeutic target. Copyright © 2015 SEHLELHA. Published by Elsevier España, S.L.U. All rights reserved.

  19. Trace glucose and lipid metabolism in high androgen and high-fat diet induced polycystic ovary syndrome rats

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    Zhai Hua-Ling

    2012-01-01

    Full Text Available Abstract Background There is a high prevalence of diabetes mellitus (DM and dyslipidemia in women with polycystic ovary syndrome (PCOS. The purpose of this study was to investigate the role of different metabolic pathways in the development of diabetes mellitus in high-androgen female mice fed with a high-fat diet. Methods Female Sprague-Dawley rats were divided into 3 groups: the control group(C, n = 10; the andronate-treated group (Andronate, n = 10 (treated with andronate, 1 mg/100 g body weight/day for 8 weeks; and the andronate-treated and high-fat diet group (Andronate+HFD, n = 10. The rate of glucose appearance (Ra of glucose, gluconeogenesis (GNG, and the rate of glycerol appearance (Ra of glycerol were assessed with a stable isotope tracer. The serum sex hormone levels, insulin levels, glucose concentration, and the lipid profile were also measured. Results Compared with control group, both andronate-treated groups exhibited obesity with higher insulin concentrations (P P Conclusions Andronate with HFD rat model showed ovarian and metabolic features of PCOS, significant increase in glucose Ra, GNG, and lipid profiles, as well as normal blood glucose levels. Therefore, aberrant IR, increased glucose Ra, GNG, and lipid metabolism may represent the early-stage of glucose and lipid kinetics disorder, thereby might be used as potential early-stage treatment targets for PCOS.

  20. Endothelial dysfunction in high fructose containing diet fed rats: Increased nitric oxide and decreased endothelin-1 levels in liver tissue

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    Zeki Arı

    2010-09-01

    Full Text Available Objectives: Dietary high fructose consumption which is closely associated with endothelial dysfunction via insulin re-sistance has recently increased in developed countries. Insulin resistance has a promoter effect on many metabolic disorders such as syndrome X, polycystic ovary syndrome, Type 2 diabetes mellitus etc. Our aim in this study is to understand the impact of increased fructose intake on metabolisms of glucose, insulin and endothelial dysfunction by measuring nitric oxide (NO and endothelin-1 (ET-1 levels in hepatic tissue which is crucial in fructose metabolism.Materials and Methods: We designed an animal study to understand increased fructose intake on hepatic endothe-lium. Twenty adult male albino rats were divided into two groups; the study group (group 1, n=10 received isocaloric fructose enriched diet (fructose-fed rats, containing 18.3% protein, 60.3% fructose and 5.2% fat while the control group received purified regular chow (group 2, n=10 for 2 weeks. After feeding period, blood and hepatic tissue samples were collected and glucose, insulin, NO and ET-1 levels were analysed.Results: We found increased fasting glucose and insulin levels and impaired glucose tolerance in fructose fed rats. Higher NO and lower ET–1 levels were also detected in hepatic tissue samples of the group 1.Conclusion: Increased fructose consumption has deleterious effects on glucose tolerance, insulin resistance and may cause to endothelial dysfunction.

  1. Astroglial Pentose Phosphate Pathway Rates in Response to High-Glucose Environments

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    Shinichi Takahashi

    2012-02-01

    Full Text Available ROS (reactive oxygen species play an essential role in the pathophysiology of diabetes, stroke and neurodegenerative disorders. Hyperglycaemia associated with diabetes enhances ROS production and causes oxidative stress in vascular endothelial cells, but adverse effects of either acute or chronic high-glucose environments on brain parenchymal cells remain unclear. The PPP (pentose phosphate pathway and GSH participate in a major defence mechanism against ROS in brain, and we explored the role and regulation of the astroglial PPP in response to acute and chronic high-glucose environments. PPP activity was measured in cultured neurons and astroglia by determining the difference in rate of 14CO2 production from [1-14C]glucose and [6-14C]glucose. ROS production, mainly H2O2, and GSH were also assessed. Acutely elevated glucose concentrations in the culture media increased PPP activity and GSH level in astroglia, decreasing ROS production. Chronically elevated glucose environments also induced PPP activation. Immunohistochemical analyses revealed that chronic high-glucose environments induced ER (endoplasmic reticulum stress (presumably through increased hexosamine biosynthetic pathway flux. Nuclear translocation of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2, which regulates G6PDH (glyceraldehyde-6-phosphate dehydrogenase by enhancing transcription, was also observed in association with BiP (immunoglobulin heavy-chain-binding protein expression. Acute and chronic high-glucose environments activated the PPP in astroglia, preventing ROS elevation. Therefore a rapid decrease in glucose level seems to enhance ROS toxicity, perhaps contributing to neural damage when insulin levels given to diabetic patients are not properly calibrated and plasma glucose levels are not adequately maintained. These findings may also explain the lack of evidence for clinical benefits from strict glycaemic control during the acute phase of stroke.

  2. Astroglial pentose phosphate pathway rates in response to high-glucose environments

    Science.gov (United States)

    Takahashi, Shinichi; Izawa, Yoshikane; Suzuki, Norihiro

    2012-01-01

    ROS (reactive oxygen species) play an essential role in the pathophysiology of diabetes, stroke and neurodegenerative disorders. Hyperglycaemia associated with diabetes enhances ROS production and causes oxidative stress in vascular endothelial cells, but adverse effects of either acute or chronic high-glucose environments on brain parenchymal cells remain unclear. The PPP (pentose phosphate pathway) and GSH participate in a major defence mechanism against ROS in brain, and we explored the role and regulation of the astroglial PPP in response to acute and chronic high-glucose environments. PPP activity was measured in cultured neurons and astroglia by determining the difference in rate of 14CO2 production from [1-14C]glucose and [6-14C]glucose. ROS production, mainly H2O2, and GSH were also assessed. Acutely elevated glucose concentrations in the culture media increased PPP activity and GSH level in astroglia, decreasing ROS production. Chronically elevated glucose environments also induced PPP activation. Immunohistochemical analyses revealed that chronic high-glucose environments induced ER (endoplasmic reticulum) stress (presumably through increased hexosamine biosynthetic pathway flux). Nuclear translocation of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2), which regulates G6PDH (glyceraldehyde-6-phosphate dehydrogenase) by enhancing transcription, was also observed in association with BiP (immunoglobulin heavy-chain-binding protein) expression. Acute and chronic high-glucose environments activated the PPP in astroglia, preventing ROS elevation. Therefore a rapid decrease in glucose level seems to enhance ROS toxicity, perhaps contributing to neural damage when insulin levels given to diabetic patients are not properly calibrated and plasma glucose levels are not adequately maintained. These findings may also explain the lack of evidence for clinical benefits from strict glycaemic control during the acute phase of stroke. PMID:22300409

  3. Effects of simvastatin on CAT-1-mediated arginine transport and NO level under high glucose conditions in conditionally immortalized rat inner blood-retinal barrier cell lines (TR-iBRB).

    Science.gov (United States)

    Tun, Temdara; Kang, Young-Sook

    2017-05-01

    Hyperglycemia causes the breakdown of the blood-retinal barrier by impairing endothelial nitric oxide synthase (eNOS) function. Statins have many pleiotropic effects such as improving endothelial barrier permeability and increasing eNOS mRNA stability. The objective of this study was to determine effect of simvastatin on l-arginine transport and NO production under high-glucose conditions in conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB). Changes in l-arginine transport uptake and, expression levels of cationic amino acid transporter 1 (CAT-1) and eNOS mRNA were investigated after pre-treatment with simvastatin and NOS inhibitors (l-NMMA and l-NAME) under high-glucose conditions using TR-iBRB, an in vitro model of iBRB. The NO level released from TR-iBRB cells was examined using Griess reagents. Under high glucose conditions, [ 3 H]l-arginine uptake was decreased in TR-iBRB cells. Simvastatin pretreatment elevated [ 3 H]l-arginine uptake, the expression levels of CAT-1 and eNOS mRNA, and NO production under high-glucose conditions. Moreover, the co-treatment with simvastatin and NOS inhibitors reduced [ 3 H]l-arginine uptake compared to pretreatment with simvastatin alone. Our results suggest that, in the presence of high-glucose levels, increased l-arginine uptake due to simvastatin treatment was associated with increased CAT-1 and eNOS mRNA levels, leading to higher NO production in TR-iBRB cells. Thus, simvastatin might be a good modulator for diabetic retinopathy therapy by increasing of the l-arginine uptake and improving endothelial function in retinal capillary endothelial cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Obesity-induced vascular dysfunction and arterial stiffening requires endothelial cell arginase 1.

    Science.gov (United States)

    Bhatta, Anil; Yao, Lin; Xu, Zhimin; Toque, Haroldo A; Chen, Jijun; Atawia, Reem T; Fouda, Abdelrahman Y; Bagi, Zsolt; Lucas, Rudolf; Caldwell, Ruth B; Caldwell, Robert W

    2017-11-01

    Elevation of arginase activity has been linked to vascular dysfunction in diabetes and hypertension by a mechanism involving decreased nitric oxide (NO) bioavailability due to L-arginine depletion. Excessive arginase activity also can drive L-arginine metabolism towards the production of ornithine, polyamines, and proline, promoting proliferation of vascular smooth muscle cells and collagen formation, leading to perivascular fibrosis. We hypothesized that there is a specific involvement of arginase 1 expression within the vascular endothelial cells in this pathology. To test this proposition, we used models of type 2 diabetes and metabolic syndrome. Studies were performed using wild type (WT), endothelial-specific arginase 1 knockout (EC-A1-/-) and littermate controls(A1con) mice fed high fat-high sucrose (HFHS) or normal diet (ND) for 6 months and isolated vessels exposed to palmitate-high glucose (PA/HG) media. Some WT mice or isolated vessels were treated with an arginase inhibitor, ABH [2-(S)-amino-6-boronohexanoic acid. In WT mice, the HFHS diet promoted increases in body weight, fasting blood glucose, and post-prandial insulin levels along with arterial stiffening and fibrosis, elevated blood pressure, decreased plasma levels of L-arginine, and elevated L-ornithine. The HFHS diet or PA/HG treatment also induced increases in vascular arginase activity along with oxidative stress, reduced vascular NO levels, and impaired endothelial-dependent vasorelaxation. All of these effects except obesity and hypercholesterolemia were prevented or significantly reduced by endothelial-specific deletion of arginase 1 or ABH treatment. Vascular dysfunctions in diet-induced obesity are prevented by deletion of arginase 1 in vascular endothelial cells or arginase inhibition. These findings indicate that upregulation of arginase 1 expression/activity in vascular endothelial cells has an integral role in diet-induced cardiovascular dysfunction and metabolic syndrome. Published

  5. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... On Up Treatment & Care Blood Glucose Testing Medication Doctors, Nurses & More Oral Health & Hygiene Women A1C Insulin Pregnancy 8 Tips for ... is checking your blood glucose often. Ask your doctor how often you should ... associated with hyperglycemia. How Do I Treat Hyperglycemia? ...

  6. Reduction in cardiolipin decreases mitochondrial spare respiratory capacity and increases glucose transport into and across human brain cerebral microvascular endothelial cells.

    Science.gov (United States)

    Nguyen, Hieu M; Mejia, Edgard M; Chang, Wenguang; Wang, Ying; Watson, Emily; On, Ngoc; Miller, Donald W; Hatch, Grant M

    2016-10-01

    Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. Cardiolipin is a mitochondrial phospholipid required for function of the electron transport chain and ATP generation. We examined the role of cardiolipin in maintaining mitochondrial function necessary to support barrier properties of brain microvessel endothelial cells. Knockdown of the terminal enzyme of cardiolipin synthesis, cardiolipin synthase, in hCMEC/D3 cells resulted in decreased cellular cardiolipin levels compared to controls. The reduction in cardiolipin resulted in decreased mitochondrial spare respiratory capacity, increased pyruvate kinase activity, and increased 2-deoxy-[(3) H]glucose uptake and glucose transporter-1 expression and localization to membranes in hCMEC/D3 cells compared to controls. The mechanism for the increase in glucose uptake was an increase in adenosine-5'-monophosphate kinase and protein kinase B activity and decreased glycogen synthase kinase 3 beta activity. Knockdown of cardiolipin synthase did not affect permeability of fluorescent dextran across confluent hCMEC/D3 monolayers grown on Transwell(®) inserts. In contrast, knockdown of cardiolipin synthase resulted in an increase in 2-deoxy-[(3) H]glucose transport across these monolayers compared to controls. The data indicate that in hCMEC/D3 cells, spare respiratory capacity is dependent on cardiolipin. In addition, reduction in cardiolipin in these cells alters their cellular energy status and this results in increased glucose transport into and across hCMEC/D3 monolayers. Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. In human adult brain endothelial cell hCMEC/D3 monolayers cultured on Transwell(®) plates, knockdown of cardiolipin synthase results in decrease in mitochondrial

  7. Endothelial function and insulin resistance in polycystic ovary syndrome: the effects of medical therapy.

    Science.gov (United States)

    Teede, Helena J; Meyer, Caroline; Hutchison, Samantha K; Zoungas, Sophia; McGrath, Barry P; Moran, Lisa J

    2010-01-01

    To assess the interaction between insulin resistance and endothelial function and the optimal treatment strategy addressing cardiovascular risk in polycystic ovary syndrome. Randomized controlled trial. Controlled clinical study. Overweight age- and body mass index-matched women with polycystic ovary syndrome. Six months metformin (1 g two times per day, n = 36) or oral contraceptive pill (OCP) (35 microg ethinyl E(2)-2 mg cytoproterone acetate, n = 30). Fasting and oral glucose tolerance test glucose and insulin levels, endothelial function (flow-mediated dilation, asymmetric dimethylarginine, plasminogen activator inhibitor-1, von Willebrand factor), inflammatory markers (high-sensitivity C-reactive protein), lipids, and hyperandrogenism. The OCP increased levels of glucose and insulin on oral glucose tolerance test, high-sensitivity C-reactive protein, triglycerides, and sex-hormone binding globulin and decreased levels of low-density lipoprotein cholesterol and T. Metformin decreased levels of fasting insulin, oral glucose tolerance test insulin, high-density lipoprotein cholesterol, and high-sensitivity C-reactive protein. Flow-mediated dilation increased only with metformin (+2.2% +/- 4.8%), whereas asymmetric dimethylarginine decreased equivalently for OCP and metformin (-0.3 +/- 0.1 vs. -0.1 +/- 0.1 mmol/L). Greater decreases in plasminogen activator inhibitor-1 occurred for the OCP than for metformin (-1.8 +/- 1.6 vs. -0.7 +/- 1.7 U/mL). In polycystic ovary syndrome, metformin improves insulin resistance, inflammatory markers, and endothelial function. The OCP worsens insulin resistance and glucose homeostasis, inflammatory markers, and triglycerides and has neutral or positive endothelial effects. The effect of the OCP on cardiovascular risk in polycystic ovary syndrome is unclear. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. A prescribed Chinese herbal medicine improves glucose profile and ameliorates oxidative stress in Goto-Kakisaki rats fed with high fat diet.

    Directory of Open Access Journals (Sweden)

    Lin Wu

    Full Text Available Oxidative stress (OS plays a role in hyperglycemia induced islet β cell dysfunction, however, studies on classic anti-oxidants didn't show positive results in treating diabetes. We previously demonstrated that the prescribed Chinese herbal medicine preparation "Qing Huo Yi Hao" (QHYH improved endothelial function in type 2 diabetic patients. QHYH protected endothelial cells from high glucose-induced damages by scavenging superoxide anion and reducing production of reactive oxygen species. Its active component protected C2C12 myotubes against palmitate-induced oxidative damage and mitochondrial dysfunction. In the present study, we investigated whether QHYH protected islet β cell function exacerbated by high fat diet (HFD in hyperglycemic GK rats. 4-week-old male rats were randomly divided into high HFD feeding group (n = 20 and chow diet feeding group (n = 10. Each gram of HFD contained 4.8 kcal of energy, 52% of which from fat. Rats on HFD were further divided into 2 groups given either QHYH (3 ml/Kg/d or saline through gastric tube. After intervention, serum glucose concentrations were monitored; IPGTTs were performed without anesthesia on 5 fasting rats randomly chosen from each group on week 4 and 16. Serum malondialdehyde (MDA concentrations and activities of serum antioxidant enzymes were measured on week 4 and 16. Islet β cell mass and OS marker staining was done by immunohistochemistry on week 16. QHYH prevented the exacerbation of hyperglycemia in HFD feeding GK rats for 12 weeks. On week 16, it improved the exacerbated glucose tolerance and prevented the further loss of islet β cell mass induced by HFD. QHYH markedly decreased serum MDA concentration, increased serum catalase (CAT and SOD activities on week 4. However, no differences of serum glucose concentration or OS were observed on week 16. We concluded that QHYH decreased hyperglycemia exacerbated by HFD in GK rats by improving β cell function partly via its

  9. Notch signaling protects retina from nuclear factor-kB- and poly-ADP-ribosepolymerase-mediated apoptosis under high-glucose stimulation

    Institute of Scientific and Technical Information of China (English)

    Xiuhong Qin1; Zhenzhen Zhang2; Haitao Xu1; and Yazhen Wu1

    2011-01-01

    Proliferative diabetic retinopathy,the primary cause of vision loss in adults,is one of serious microvascular complications caused by diabetes.Both poly-ADP-ribosepolymerase (PARP) and nuclear factor (NF)-kB signaling are involved in the injury process.Injury activates PARP,which in turn potentiates NF-kB activation and causes cell apoptosis.Like the NF-kB pathway,Notch1 signaling plays a key role in the regulation of cell proliferation,differentiation,and apoptosis.However,the connections between these signaling pathways are not well understood.In this study,we used both streptozotocin (STZ)-induced diabetic mice and human retinal vascular endothelial cells (HRVECs) cultured in high glucose to detect these relationships.We found that apoptosis was increased in both STZinduced diabetic mice and high-glucose-treated HRVECs,which was due to increased activation of PARP,cleaved caspase3,and reduced expression of Notch1 and p-Akt.The results of Notch1 overexpression and knockdown indicated that Notch1 signaling participated in the interaction of PARP and p50,and inhibited PARP- and p50-mediated apoptosis directly.These phenomena could be blocked by pretreatment with the PI3K inhibitor wortmannin via reducing p-Akt levels.Thus,our study demonstrated that Notch1 signaling protects cells from PARP- and NF-kB-induced apoptosis under high glucose through the activation of Akt.

  10. Lenalidomide, an anti-tumor drug, regulates retinal endothelial cell function: Implication for treating ocular neovascular disorder

    International Nuclear Information System (INIS)

    Dong, Ling-Feng; Yao, Jin; Wang, Xiao-Qun; Shan, Kun; Yang, Hong; Yan, Biao; Jiang, Qin

    2015-01-01

    Ocular angiogenesis is an important pathologic character of several ocular diseases, such as retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration (AMD). Inhibition of ocular angiogenesis has great therapeutic value for treating these dieses. Here we show that lenalidomide, an anti-tumor drug, has great anti-angiogenic potential in ocular diseases. Lenalidomide inhibits retinal endothelial cell viability in normal and pathological condition, and inhibits VEGF-induced endothelial cell migration and tube formation in vitro. Moreover, lenalidomide inhibits ocular angiogenesis in vivo through the reduction of angiogenesis- and inflammation-related protein expression. Collectively, lenalidomide is a promising drug for treating ocular angiogenesis through its anti-proliferative and anti-inflammatory property. - Highlights: • Lenalidomide inhibits retinal endothelial cell viability in vitro. • Lenalidomide inhibits retinal endothelial cell migration and tube formation. • Lenalidomide inhibits pathological ocular angiogenesis in vivo. • Lenalidomide inhibits angiogenesis- and inflammation-related protein expression.

  11. Lenalidomide, an anti-tumor drug, regulates retinal endothelial cell function: Implication for treating ocular neovascular disorder

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Ling-Feng; Yao, Jin; Wang, Xiao-Qun; Shan, Kun; Yang, Hong [Eye Hospital, Nanjing Medical University, Nanjing (China); The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing (China); Yan, Biao, E-mail: yanbiao1982@hotmail.com [Eye Hospital, Nanjing Medical University, Nanjing (China); The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing (China); Jiang, Qin, E-mail: jiangqin710@126.com [Eye Hospital, Nanjing Medical University, Nanjing (China); The Fourth School of Clinical Medicine, Nanjing Medical University, Nanjing (China)

    2015-10-02

    Ocular angiogenesis is an important pathologic character of several ocular diseases, such as retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration (AMD). Inhibition of ocular angiogenesis has great therapeutic value for treating these dieses. Here we show that lenalidomide, an anti-tumor drug, has great anti-angiogenic potential in ocular diseases. Lenalidomide inhibits retinal endothelial cell viability in normal and pathological condition, and inhibits VEGF-induced endothelial cell migration and tube formation in vitro. Moreover, lenalidomide inhibits ocular angiogenesis in vivo through the reduction of angiogenesis- and inflammation-related protein expression. Collectively, lenalidomide is a promising drug for treating ocular angiogenesis through its anti-proliferative and anti-inflammatory property. - Highlights: • Lenalidomide inhibits retinal endothelial cell viability in vitro. • Lenalidomide inhibits retinal endothelial cell migration and tube formation. • Lenalidomide inhibits pathological ocular angiogenesis in vivo. • Lenalidomide inhibits angiogenesis- and inflammation-related protein expression.

  12. Let-7i attenuates human brain microvascular endothelial cell damage in oxygen glucose deprivation model by decreasing toll-like receptor 4 expression.

    Science.gov (United States)

    Xiang, Wei; Tian, Canhui; Peng, Shunli; Zhou, Liang; Pan, Suyue; Deng, Zhen

    2017-11-04

    The let-7 family of microRNAs (miRNAs) plays an important role on endothelial cell function. However, there have been few studies on their role under ischemic conditions. In this study, we demonstrate that let-7i, belonging to the let-7 family, rescues human brain microvascular endothelial cells (HBMECs) in an oxygen-glucose deprivation (OGD) model. Our data show that the expression of let-7 family miRNAs was downregulated after OGD. Overexpression of let-7i significantly alleviated cell death and improved survival of OGD-treated HBMECs. Let-7i also protected permeability in an in vitro blood brain barrier (BBB) model. Further, let-7i downregulated the expression of toll-like receptor 4 (TLR4), an inflammation trigger. Moreover, overexpression of let-7i decreased matrix metallopeptidase 9 (MMP9) and inducible nitric oxide synthase (iNOS) expression under OGD. Upon silencing TLR4 expression in HBMECs, the anti-inflammatory effect of let-7i was abolished. Our research suggests that let-7i promotes OGD-induced inflammation via downregulating TLR4 expression. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. High glucose alters retinal astrocytes phenotype through increased production of inflammatory cytokines and oxidative stress.

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    Full Text Available Astrocytes are macroglial cells that have a crucial role in development of the retinal vasculature and maintenance of the blood-retina-barrier (BRB. Diabetes affects the physiology and function of retinal vascular cells including astrocytes (AC leading to breakdown of BRB. However, the detailed cellular mechanisms leading to retinal AC dysfunction under high glucose conditions remain unclear. Here we show that high glucose conditions did not induce the apoptosis of retinal AC, but instead increased their rate of DNA synthesis and adhesion to extracellular matrix proteins. These alterations were associated with changes in intracellular signaling pathways involved in cell survival, migration and proliferation. High glucose conditions also affected the expression of inflammatory cytokines in retinal AC, activated NF-κB, and prevented their network formation on Matrigel. In addition, we showed that the attenuation of retinal AC migration under high glucose conditions, and capillary morphogenesis of retinal endothelial cells on Matrigel, was mediated through increased oxidative stress. Antioxidant proteins including heme oxygenase-1 and peroxiredoxin-2 levels were also increased in retinal AC under high glucose conditions through nuclear localization of transcription factor nuclear factor-erythroid 2-related factor-2. Together our results demonstrated that high glucose conditions alter the function of retinal AC by increased production of inflammatory cytokines and oxidative stress with significant impact on their proliferation, adhesion, and migration.

  14. Effect of peritoneal dialysis fluid containing osmo-metabolic agents on human endothelial cells

    Directory of Open Access Journals (Sweden)

    Bonomini M

    2016-11-01

    Full Text Available Mario Bonomini,1,2 Sara Di Silvestre,3,4 Pamela Di Tomo,3,4 Natalia Di Pietro,2,4 Domitilla Mandatori,3,4 Lorenzo Di Liberato,1 Vittorio Sirolli,1,2 Francesco Chiarelli,2,4 Cesare Indiveri,5 Assunta Pandolfi,3,4 Arduino Arduini6 1Unit of Nephrology and Dialysis, 2Department of Medicine and Aging Sciences, 3Department of Medical, Oral and Biotechnological Sciences, 4Aging Research Center and Translational Medicine, CeSI-MeT, University “G. d’Annunzio”, Chieti-Pescara, 5Department DiBEST (Biologia, Ecologia, Scienze della Terra, Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende CS, Italy; 6CoreQuest, Manno, Switzerland Background: The use of glucose as the only osmotic agent in peritoneal dialysis (PD solutions (PDSs is believed to exert local (peritoneal and systemic detrimental actions, particularly in diabetic PD patients. To improve peritoneal biocompatibility, we have developed more biocompatible PDSs containing xylitol and carnitine along with significantly less amounts of glucose and have tested them in cultured Human Vein Endothelial Cells (HUVECs obtained from the umbilical cords of healthy (C and gestational diabetic (GD mothers. Methods: Primary C- and GD-HUVECs were treated for 72 hours with our PDSs (xylitol 0.7% and 1.5%, whereas carnitine and glucose were fixed at 0.02% and 0.5%, respectively and two glucose-based PDSs (glucose 1.36% or 2.27%. We examined their effects on endothelial cell proliferation (cell count, viability (3-(4,5-dimethylthiazolyl-2-2,5-diphenyltetrazolium bromide assay, intracellular nitro-oxidative stress (peroxynitrite levels, Vascular Cell Adhesion Molecule-1 and Intercellular Adhesion Molecule-1 membrane exposure (flow cytometry, and HUVEC-monocyte interactions (U937 adhesion assay. Results: Compared to glucose-based PDSs, our in vitro studies demonstrated that the tested PDSs did not change the proliferative potential both in C- and GD-HUVECs. Moreover, our

  15. Effects of Berberine on Amelioration of Hyperglycemia and Oxidative Stress in High Glucose and High Fat Diet-Induced Diabetic Hamsters In Vivo

    Directory of Open Access Journals (Sweden)

    Cong Liu

    2015-01-01

    Full Text Available This study investigated the effects of berberine on amelioration of hyperglycemia and hyperlipidemia and the mechanism involved in high glucose and high fat diet-induced diabetic hamsters. Golden hamsters fed with high glucose and high fat diet were medicated with metformin, simvastatin, and low or high dose of berberine (50 and 100 mg·kg−1 for 6 weeks. The results showed that the body weights were significantly lower in berberine-treated groups than control group. Histological analyses revealed that the treatment of berberine inhibited hepatic fat accumulation. Berberine significantly reduced plasma total cholesterol, triglyceride, free fatty acid, low density lipoprotein cholesterol, malondialdehyde, thiobarbituric acid-reactive substance, and 8-isoprostane level but significantly increased plasma superoxide dismutase activity. Glucose and insulin levels were significantly reduced in metformin and berberine-treated groups. Glucose tolerance tests documented that berberine-treated mice were more glucose tolerant. Berberine treatment increased expression of skeletal muscle glucose transporter 4 mRNA and significantly decreased liver low density lipoprotein receptor mRNA expression. The study suggested that berberine was effective in lowering blood glucose and lipids levels, reducing the body weight, and alleviating the oxidative stress in diabetic hamsters, which might be beneficial in reducing the cardiovascular risk factors in diabetes.

  16. Fenofibrate suppresses cellular metabolic memory of high glucose in diabetic retinopathy via a sirtuin 1-dependent signalling pathway.

    Science.gov (United States)

    Zhao, Shuzhi; Li, Jun; Wang, Na; Zheng, Bingqing; Li, Tao; Gu, Qing; Xu, Xun; Zheng, Zhi

    2015-10-01

    Inflammation is a major contributing factor in the development of diabetic microvascular complications, regardless of whether improved glycaemic control is achieved. Studies have increasingly indicated that fenofibrate, a lipid‑lowering therapeutic agent in clinical use, exerts a potential anti‑inflammatory effect, which is mediated by sirtuin 1 (SIRT1; an NAD+‑dependent deacetylase) in endothelial cells. The aim of the present study was to investigate the inhibitory effect of fenofibrate on metabolic memory (via the regulation of SIRT1), and inflammatory responses in cell and animal models of diabetic retinopathy (DR). The data demonstrated that high glucose treatment in human retinal endothelial cells (HRECs) inhibited the expression and deacetylase activity of SIRT1. The reduction of SIRT1 expression and deacetylase activity persisted following a return to normal glucose levels. Furthermore, nuclear factor‑κB expression was observed to be negatively correlated with SIRT1 expression and activity in HRECs under high glucose levels and the subsequent return to normal glucose levels. Fenofibrate treatment abrogated these changes. Knockdown of SIRT1 attenuated the effect of fenofibrate on high glucose‑induced NF‑κB expression. In addition, fenofibrate upregulated SIRT1 expression through peroxisome proliferator‑activated receptor α in high glucose‑induced metabolic memory. These findings indicate that fenofibrate is important in anti‑inflammatory processes and suppresses the cellular metabolic memory of high glucose‑induced stress via the SIRT1‑dependent signalling pathway. Thus, treatment with fenofibrate may offer a promising therapeutic strategy for halting the development of DR and other complications of diabetes.

  17. Inhibitory Effects of Ecklonia cava Extract on High Glucose-Induced Hepatic Stellate Cell Activation

    Directory of Open Access Journals (Sweden)

    Akiko Kojima-Yuasa

    2011-12-01

    Full Text Available Nonalcoholic steatohepatitis (NASH is a disease closely associated with obesity and diabetes. A prevalence of type 2 diabetes and a high body mass index in cryptogenic cirrhosis may imply that obesity leads to cirrhosis. Here, we examined the effects of an extract of Ecklonia cava, a brown algae, on the activation of high glucose-induced hepatic stellate cells (HSCs, key players in hepatic fibrosis. Isolated HSCs were incubated with or without a high glucose concentration. Ecklonia cava extract (ECE was added to the culture simultaneously with the high glucose. Treatment with high glucose stimulated expression of type I collagen and α-smooth muscle actin, which are markers of activation in HSCs, in a dose-dependent manner. The activation of high glucose-treated HSCs was suppressed by the ECE. An increase in the formation of intracellular reactive oxygen species (ROS and a decrease in intracellular glutathione levels were observed soon after treatment with high glucose, and these changes were suppressed by the simultaneous addition of ECE. High glucose levels stimulated the secretion of bioactive transforming growth factor-β (TGF-β from the cells, and the stimulation was also suppressed by treating the HSCs with ECE. These results suggest that the suppression of high glucose-induced HSC activation by ECE is mediated through the inhibition of ROS and/or GSH and the downregulation of TGF-β secretion. ECE is useful for preventing the development of diabetic liver fibrosis.

  18. Red Yeast Rice Protects Circulating Bone Marrow-Derived Proangiogenic Cells against High-Glucose-Induced Senescence and Oxidative Stress: The Role of Heme Oxygenase-1

    Directory of Open Access Journals (Sweden)

    Jung-Tung Liu

    2017-01-01

    Full Text Available The inflammation and oxidative stress of bone marrow-derived proangiogenic cells (PACs, also named endothelial progenitor cells, triggered by hyperglycemia contributes significantly to vascular dysfunction. There is supporting evidence that the consumption of red yeast rice (RYR; Monascus purpureus-fermented rice reduces the vascular complications of diabetes; however, the underlying mechanism remains unclear. This study aimed to elucidate the effects of RYR extract in PACs, focusing particularly on the role of a potent antioxidative enzyme, heme oxygenase-1 (HO-1. We found that treatment with RYR extract induced nuclear factor erythroid-2-related factor nuclear translocation and HO-1 mRNA and protein levels in PACs. RYR extract inhibited high-glucose-induced (30 mM PAC senescence and the development of reactive oxygen species (ROS in a dose-dependent manner. The HO-1 inducer cobalt protoporphyrin IX also decreased high-glucose-induced cell senescence and oxidative stress, whereas the HO-1 enzyme inhibitor zinc protoporphyrin IX and HO-1 small interfering RNA significantly reversed RYR extract-caused inhibition of senescence and reduction of oxidative stress in high-glucose-treated PACs. These results suggest that RYR extract serves as alternative and complementary medicine in the treatment of these diseases, by inducing HO-1, thereby decreasing the vascular complications of diabetes.

  19. Consumption of High-Polyphenol Dark Chocolate Improves Endothelial Function in Individuals with Stage 1 Hypertension and Excess Body Weight

    Directory of Open Access Journals (Sweden)

    Lívia de Paula Nogueira

    2012-01-01

    Full Text Available Background. Hypertension and excess body weight are important risk factors for endothelial dysfunction. Recent evidence suggests that high-polyphenol dark chocolate improves endothelial function and lowers blood pressure. This study aimed to evaluate the association of chocolate 70% cocoa intake with metabolic profile, oxidative stress, inflammation, blood pressure, and endothelial function in stage 1 hypertensives with excess body weight. Methods. Intervention clinical trial includes 22 stage 1 hypertensives without previous antihypertensive treatment, aged 18 to 60 years and presents a body mass index between 25.0 and 34.9 kg/m2. All participants were instructed to consume 50 g of chocolate 70% cocoa/day (2135 mg polyphenols for 4 weeks. Endothelial function was evaluated by peripheral artery tonometry using Endo-PAT 2000 (Itamar Medical. Results. Twenty participants (10 men completed the study. Comparison of pre-post intervention revealed that (1 there were no significant changes in anthropometric parameters, percentage body fat, glucose metabolism, lipid profile, biomarkers of inflammation, adhesion molecules, oxidized LDL, and blood pressure; (2 the assessment of endothelial function through the reactive hyperemia index showed a significant increase: 1.94 ± 0.18 to 2.22 ± 0.08, P=0.01. Conclusion.In individuals with stage 1 hypertension and excess body weight, high-polyphenol dark chocolate improves endothelial function.

  20. l-Cysteine supplementation increases insulin sensitivity mediated by upregulation of GSH and adiponectin in high glucose treated 3T3-L1 adipocytes.

    Science.gov (United States)

    Achari, Arunkumar E; Jain, Sushil K

    2017-09-15

    Diabetic patients have lower blood levels of l-cysteine (LC) and glutathione (GSH). This study examined the hypothesis that LC supplementation positively up regulates the effects of insulin on GSH and glucose metabolism in 3T3-L1 adipocyte model. 3T3L1 adipocytes were treated with LC (250 μM, 2 h) and/or insulin (15 or 30 nM, 2 h), and high glucose (HG, 25 mM, 20 h). Results showed that HG caused significant increase (95%) in ROS and reduction in the protein levels of DsbA-L (43%), adiponectin (64%), GCLC (20%), GCLM (21%), GSH (50%), and GLUT-4 (23%) in adipocytes. Furthermore, HG caused a reduction in total (35%) and HMW adiponectin (30%) secretion. Treatment with insulin alone significantly (p L, adiponectin, GCLC, GCLM, GSH, and GLUT-4 protein levels, glucose utilization, and improved total and HMW adiponectin secretion in HG treated adipocytes compared to HG alone. Interestingly, LC supplementation along with insulin caused greater reduction in ROS levels and significantly (p L (41% vs LC, 29% vs Insulin), adiponectin (92% Vs LC, 84% Vs insulin) protein levels and total (32% Vs LC, 22% Vs insulin) and HMW adiponectin (75% Vs LC, 39% Vs insulin) secretion compared with the either insulin or LC alone in HG-treated cells. In addition, LC supplementation along with insulin increased GCLC (21% Vs LC, 14% insulin), GCLM (28% Vs LC, 16% insulin) and GSH (25% Vs LC and insulin) levels compared with the either insulin or LC alone in HG-treated cells. Furthermore, LC and insulin increases GLUT-4 protein expression (65% Vs LC, 18% Vs Insulin), glucose utilization (57% Vs LC, 27% Vs insulin) compared with the either insulin or LC alone in HG-treated cells. Similarly, LC supplementation increased insulin action significantly in cells maintained in medium contained control glucose. To explore the beneficial effect of LC is mediated by the upregulation of GCLC, we knocked down GCLC using siRNA in adipoctyes. There was a significant decrease in DsbA-L and GLUT-4 m

  1. Endothelial cell behaviour on gas-plasma-treated PLA surfaces: the roles of surface chemistry and roughness.

    Science.gov (United States)

    Shah, Amita; Shah, Sarita; Mani, Gopinath; Wenke, Joseph; Agrawal, Mauli

    2011-04-01

    Glow-discharge gas-plasma (GP) treatment has been shown to induce surface modifications such that cell adhesion and growth are enhanced. However, it is not known which gas used in GP treatment is optimal for endothelial cell function. Polylactic acid (PLA) films treated oxygen, argon, or nitrogen GP were characterized using contact angles, scanning electron microscopy, atomic force microscopy, optical profilometry, and x-ray photoelectron spectroscopy. All three GP treatments decreased the carbon atomic concentration and surface roughness and increased the oxygen atomic concentration. Human umbilical vein endothelial cells were cultured on the PLA films for up to 7 days. Based on proliferation and live/dead assays, surface chemistry was shown to have the greatest effect on the attachment, proliferation, and viability of these cells, while roughness did not have a significant influence. Of the different gases, endothelial cell viability, attachment and proliferation were most significantly increased on PLA surfaces treated with oxygen and argon gas plasma. Copyright © 2010 John Wiley & Sons, Ltd.

  2. Nicorandil prevents endothelial dysfunction due to antioxidative effects via normalisation of NADPH oxidase and nitric oxide synthase in streptozotocin diabetic rats

    Directory of Open Access Journals (Sweden)

    Serizawa Ken-ichi

    2011-11-01

    Full Text Available Abstract Background Nicorandil, an anti-angina agent, reportedly improves outcomes even in angina patients with diabetes. However, the precise mechanism underlying the beneficial effect of nicorandil on diabetic patients has not been examined. We investigated the protective effect of nicorandil on endothelial function in diabetic rats because endothelial dysfunction is a major risk factor for cardiovascular disease in diabetes. Methods Male Sprague-Dawley rats (6 weeks old were intraperitoneally injected with streptozotocin (STZ, 40 mg/kg, once a day for 3 days to induce diabetes. Nicorandil (15 mg/kg/day and tempol (20 mg/kg/day, superoxide dismutase mimetic were administered in drinking water for one week, starting 3 weeks after STZ injection. Endothelial function was evaluated by measuring flow-mediated dilation (FMD in the femoral arteries of anaesthetised rats. Cultured human coronary artery endothelial cells (HCAECs were treated with high glucose (35.6 mM, 24 h and reactive oxygen species (ROS production with or without L-NAME (300 μM, apocynin (100 μM or nicorandil (100 μM was measured using fluorescent probes. Results Endothelial function as evaluated by FMD was significantly reduced in diabetic as compared with normal rats (diabetes, 9.7 ± 1.4%; normal, 19.5 ± 1.7%; n = 6-7. There was a 2.4-fold increase in p47phox expression, a subunit of NADPH oxidase, and a 1.8-fold increase in total eNOS expression in diabetic rat femoral arteries. Nicorandil and tempol significantly improved FMD in diabetic rats (nicorandil, 17.7 ± 2.6%; tempol, 13.3 ± 1.4%; n = 6. Nicorandil significantly inhibited the increased expressions of p47phox and total eNOS in diabetic rat femoral arteries. Furthermore, nicorandil significantly inhibited the decreased expression of GTP cyclohydrolase I and the decreased dimer/monomer ratio of eNOS. ROS production in HCAECs was increased by high-glucose treatment, which was prevented by L-NAME and nicorandil

  3. Endothelial dysfunction in metabolic and vascular disorders.

    Science.gov (United States)

    Polovina, Marija M; Potpara, Tatjana S

    2014-03-01

    Vascular endothelium has important regulatory functions in the cardiovascular system and a pivotal role in the maintenance of vascular health and metabolic homeostasis. It has long been recognized that endothelial dysfunction participates in the pathogenesis of atherosclerosis from early, preclinical lesions to advanced, thrombotic complications. In addition, endothelial dysfunction has been recently implicated in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Considering that states of insulin resistance (eg, metabolic syndrome, impaired fasting glucose, impaired glucose tolerance, and T2DM) represent the most prevalent metabolic disorders and risk factors for atherosclerosis, it is of considerable scientific and clinical interest that both metabolic and vascular disorders have endothelial dysfunction as a common background. Importantly, endothelial dysfunction has been associated with adverse outcomes in patients with established cardiovascular disease, and a growing body of evidence indicates that endothelial dysfunction also imparts adverse prognosis in states of insulin resistance. In this review, we discuss the association of insulin resistance and T2DM with endothelial dysfunction and vascular disease, with a focus on the underlying mechanisms and prognostic implications of the endothelial dysfunction in metabolic and vascular disorders. We also address current therapeutic strategies for the improvement of endothelial dysfunction.

  4. Effects of Mangifera indica (Careless) on Microcirculation and Glucose Metabolism in Healthy Volunteers.

    Science.gov (United States)

    Buchwald-Werner, Sybille; Schön, Christiane; Frank, Sonja; Reule, Claudia

    2017-07-01

    A commercial Mangifera indica fruit powder (Careless) showed beneficial acute effects on microcirculation in a randomized, double-blind, crossover pilot study. Here, long-term effects on microcirculation and glucose metabolism were investigated in a double-blind, randomized, placebo-controlled, 3-arm parallel-design study in healthy individuals. A daily dose of 100 mg or 300 mg of the fruit powder was compared to placebo after supplementation for 4 weeks. Microcirculation and endothelial function were assessed by the Oxygen-to-see System and pulse amplitude tonometry, respectively. Glucose metabolism was assessed under fasting and postprandial conditions by capillary glucose and HbA1c values.Microcirculatory reactive hyperemia flow increased, especially in the 100 mg group (p = 0.025). The 300 mg of the M. indica fruit preparation reduced postprandial glucose levels by trend if compared to placebo (p = 0.0535) accompanied by significantly lower HbA1c values compared to baseline. Furthermore, 300 mg intake significantly improved postprandial endothelial function in individuals with decreased endothelial function after high-dose glucose intake (p = 0.0408; n = 11).In conclusion, the study suggests moderate beneficial effects of M. indica fruit preparation on microcirculation, endothelial function, and glucose metabolism. Georg Thieme Verlag KG Stuttgart · New York.

  5. Effects of exposure to high glucose on primary cultured hippocampal neurons: involvement of intracellular ROS accumulation.

    Science.gov (United States)

    Liu, Di; Zhang, Hong; Gu, Wenjuan; Zhang, Mengren

    2014-06-01

    Recent studies showed that hyperglycemia is the main trigger of diabetic cognitive impairment and can cause hippocampus abnormalities. The goal of this study is to explore the effects of different concentrations of high glucose for different exposure time on cell viability as well as intracellular reactive oxygen species (ROS) generation of primary cultured hippocampal neurons. Hippocampal neurons were exposed to different concentrations of high glucose (50, 75, 100, 125, and 150 mM) for 24, 48, 72 and 96 h. Cell viability and nuclear morphology were evaluated by MTT and Hoechst assays, respectively. Intracellular ROS were monitored using the fluorescent probe DCFH-DA. The results showed that, compared with control group, the cell viability of all high glucose-treated groups decreased significantly after 72 h and there also was a significant increase of apoptotic nuclei in high glucose-treated groups from 72 to 96 h. Furthermore, 50 mM glucose induced a peak rise in ROS generation at 24 h and the intracellular ROS levels of 50 mM glucose group were significantly higher than the corresponding control group from 6 to 72 h. These results suggest that hippocampal neurons could be injured by high glucose exposure and the neuronal injury induced by high glucose is potentially mediated through intracellular ROS accumulation.

  6. The effect of metformin on monocyte secretory function in simvastatin-treated patients with impaired fasting glucose.

    Science.gov (United States)

    Krysiak, Robert; Okopien, Bogusław

    2013-01-01

    This study was designed to investigate whether metformin affects monocyte secretory function in patients with impaired fasting glucose receiving chronic statin therapy. The study included 48 patients with impaired fasting glucose treated for at least three months with simvastatin (40 mg daily). These patients were randomized to either metformin (3 g daily) or placebo, which was administered together with simvastatin for 90 days. Plasma lipids, glucose homeostasis markers, monocyte cytokine release and plasma C-reactive protein levels were determined before randomization and at the end of the treatment. Compared to placebo, metformin reduced monocyte release of tumor necrosis factor-α, interleukin-1β, interleukin-6, monocyte chemoattractant protein-1 and interleukin-8, as well as decreased plasma C-reactive protein levels, which were accompanied by an improvement in insulin sensitivity. The obtained results suggest that metformin may inhibit monocyte secretory function and reduce systemic inflammation in statin-treated patients with prediabetes. Impaired fasting glucose patients with high cardiovascular risk may receive the greatest benefits from concomitant treatment with a statin and metformin. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. High Blood Glucose: What It Means and How To Treat It

    Science.gov (United States)

    ... People who do not have diabetes typically have fasting plasma blood glucose levels that run under 100 ... blood glucose? Be sure to drink plenty of water. It is recommended to drink a minimum of ...

  8. Geraniol improves endothelial function by inhibiting NOX-2 derived oxidative stress in high fat diet fed mice

    International Nuclear Information System (INIS)

    Wang, Xiaoyu; Zhao, Shiqi; Su, Mengqi; Sun, Li; Zhang, Song; Wang, Dingyu; Liu, Zhaorui; Yuan, Yue; Liu, Yang; Li, Yue

    2016-01-01

    Endothelial dysfunction occurs in obese patients and high-fat diet (HFD) fed experimental animals. While geraniol has been reported to ameliorate inflammation and oxidative stress, inhibit tumor cell proliferation, and improve atherosclerosis, its direct effect on endothelial function remains uncharacterized. The present study therefore investigated the effect of geraniol on endothelial function in HFD mice and its underlying mechanisms. C57 BL/6 mice were fed an HFD (n = 40) or a normal diet (n = 20) for 8 weeks. HFD fed mice then were randomized to intraperitoneal treatment with geraniol (n = 20) or vehicle (n = 20) for another 6 weeks. Acetylcholine (Ach)-induced endothelial dependent vasorelaxation was measured on wire myography; reactive oxygen species (ROS) generation was assessed by fluorescence imaging, and NADPH oxidases (NOXs) and adhesive molecules VCAM-1 and ICAM-1 protein expression by western blotting. Geraniol improved endothelial function in HFD fed mice, as evidenced by its: 1. restoring endothelial dependent vasorelaxation induced by Ach, and reversing increased VCAM-1 and ICAM-1 expression; 2. attenuating HFD induced increased serum TBARS and aortic ROS generation; and 3. downregulating aortic NOX-2 expression in both HFD fed mice and in palmitic acid treated endothelial cells. Geraniol therefore protects against endothelial dysfunction induced by HFD through reducing NOX-2 associated ROS generation. -- Highlights: •Geraniol improved endothelial dependent relaxation in high fat diet fed mice. •Geraniol alleviated vascular injury in high fat diet fed mice. •Geraniol inhibited ROS generation through downregulating NOX-2 expression.

  9. Geraniol improves endothelial function by inhibiting NOX-2 derived oxidative stress in high fat diet fed mice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaoyu; Zhao, Shiqi; Su, Mengqi; Sun, Li; Zhang, Song; Wang, Dingyu; Liu, Zhaorui; Yuan, Yue; Liu, Yang [Department of Cardiology, the First Affiliated Hospital, Harbin Medical University, Harbin 150001, Heilongjiang Province (China); Li, Yue, E-mail: ly99ly@vip.163.com [Department of Cardiology, the First Affiliated Hospital, Harbin Medical University, Harbin 150001, Heilongjiang Province (China); Key Laboratory of Cardiac Diseases and Heart Failure, Harbin Medical University, Harbin, 150001, Heilongjiang Province (China)

    2016-05-20

    Endothelial dysfunction occurs in obese patients and high-fat diet (HFD) fed experimental animals. While geraniol has been reported to ameliorate inflammation and oxidative stress, inhibit tumor cell proliferation, and improve atherosclerosis, its direct effect on endothelial function remains uncharacterized. The present study therefore investigated the effect of geraniol on endothelial function in HFD mice and its underlying mechanisms. C57 BL/6 mice were fed an HFD (n = 40) or a normal diet (n = 20) for 8 weeks. HFD fed mice then were randomized to intraperitoneal treatment with geraniol (n = 20) or vehicle (n = 20) for another 6 weeks. Acetylcholine (Ach)-induced endothelial dependent vasorelaxation was measured on wire myography; reactive oxygen species (ROS) generation was assessed by fluorescence imaging, and NADPH oxidases (NOXs) and adhesive molecules VCAM-1 and ICAM-1 protein expression by western blotting. Geraniol improved endothelial function in HFD fed mice, as evidenced by its: 1. restoring endothelial dependent vasorelaxation induced by Ach, and reversing increased VCAM-1 and ICAM-1 expression; 2. attenuating HFD induced increased serum TBARS and aortic ROS generation; and 3. downregulating aortic NOX-2 expression in both HFD fed mice and in palmitic acid treated endothelial cells. Geraniol therefore protects against endothelial dysfunction induced by HFD through reducing NOX-2 associated ROS generation. -- Highlights: •Geraniol improved endothelial dependent relaxation in high fat diet fed mice. •Geraniol alleviated vascular injury in high fat diet fed mice. •Geraniol inhibited ROS generation through downregulating NOX-2 expression.

  10. Perspectives of patients with non-insulin-treated type 2 diabetes on self-monitoring of blood glucose: A qualitative study.

    Science.gov (United States)

    Chen, Chen-Mei; Hung, Li-Chen; Chen, Yang-Lin; Yeh, Mei Chang

    2018-04-01

    To explore experiences of self-monitoring of blood glucose among patients with non-insulin-treated type 2 diabetes. Self-monitoring of blood glucose is essential to diabetes care and facilitates glycaemic control. Patients' perspectives of self-monitoring of blood glucose have seldom been discussed in the literature, and engagement in self-monitoring of blood glucose is consistently low. The descriptive phenomenological method was used. Purposive sampling was conducted to recruit participants from the endocrinology departments of medical institutions in Taiwan based on the following criteria: (i) having a medical diagnosis of type 2 diabetes, (ii) not being treated with insulin, (iii) having engaged in self-monitoring of blood glucose at least once within the preceding 6 months, (iv) being at least 20 years old and (v) not having any major mental or cognitive disorders. Data were collected in outpatient consultation rooms, the participants' homes and other settings where the participants felt secure and comfortable. In-depth interviews were conducted to collect data from 16 patients with diabetes. The participants perceived that lifestyle affected blood glucose levels and did not know how to handle high or low blood glucose levels. Their willingness to continue self-monitoring of blood glucose depended on whether healthcare professionals checked or discussed their blood glucose levels with them. The patients' knowledge regarding blood glucose variation and healthcare professionals' attitudes affected the patients' self-monitoring of blood glucose behaviours. The empirical findings illustrated self-monitoring of blood glucose experiences and recommended that healthcare professionals' closely attend to patients' requirements and responses to diabetes and incorporate the self-monitoring of blood glucose into therapy plans. Healthcare professionals should reinforce patients' knowledge on appropriate responses to high and low blood glucose levels, intervene

  11. Inhibition of Endothelial p53 Improves Metabolic Abnormalities Related to Dietary Obesity

    Directory of Open Access Journals (Sweden)

    Masataka Yokoyama

    2014-06-01

    Full Text Available Accumulating evidence has suggested a role for p53 activation in various age-associated conditions. Here, we identified a crucial role of endothelial p53 activation in the regulation of glucose homeostasis. Endothelial expression of p53 was markedly upregulated when mice were fed a high-calorie diet. Disruption of endothelial p53 activation improved dietary inactivation of endothelial nitric oxide synthase that upregulated the expression of peroxisome proliferator-activated receptor-γ coactivator-1α in skeletal muscle, thereby increasing mitochondrial biogenesis and oxygen consumption. Mice with endothelial cell-specific p53 deficiency fed a high-calorie diet showed improvement of insulin sensitivity and less fat accumulation, compared with control littermates. Conversely, upregulation of endothelial p53 caused metabolic abnormalities. These results indicate that inhibition of endothelial p53 could be a novel therapeutic target to block the vicious cycle of cardiovascular and metabolic abnormalities associated with obesity.

  12. Endothelial mineralocorticoid receptor activation mediates endothelial dysfunction in diet-induced obesity.

    Science.gov (United States)

    Schäfer, Nicola; Lohmann, Christine; Winnik, Stephan; van Tits, Lambertus J; Miranda, Melroy X; Vergopoulos, Athanasios; Ruschitzka, Frank; Nussberger, Jürg; Berger, Stefan; Lüscher, Thomas F; Verrey, François; Matter, Christian M

    2013-12-01

    Aldosterone plays a crucial role in cardiovascular disease. 'Systemic' inhibition of its mineralocorticoid receptor (MR) decreases atherosclerosis by reducing inflammation and oxidative stress. Obesity, an important cardiovascular risk factor, is an inflammatory disease associated with increased plasma aldosterone levels. We have investigated the role of the 'endothelial' MR in obesity-induced endothelial dysfunction, the earliest stage in atherogenesis. C57BL/6 mice were exposed to a normal chow diet (ND) or a high-fat diet (HFD) alone or in combination with the MR antagonist eplerenone (200 mg/kg/day) for 14 weeks. Diet-induced obesity impaired endothelium-dependent relaxation in response to acetylcholine, whereas eplerenone treatment of obese mice prevented this. Expression analyses in aortic endothelial cells isolated from these mice revealed that eplerenone attenuated expression of pro-oxidative NADPH oxidase (subunits p22phox, p40phox) and increased expression of antioxidative genes (glutathione peroxidase-1, superoxide dismutase-1 and -3) in obesity. Eplerenone did not affect obesity-induced upregulation of cyclooxygenase (COX)-1 or prostacyclin synthase. Endothelial-specific MR deletion prevented endothelial dysfunction in obese (exhibiting high 'endogenous' aldosterone) and in 'exogenous' aldosterone-infused lean mice. Pre-incubation of aortic rings from aldosterone-treated animals with the COX-inhibitor indomethacin restored endothelial function. Exogenous aldosterone administration induced endothelial expression of p22phox in the presence, but not in the absence of the endothelial MR. Obesity-induced endothelial dysfunction depends on the 'endothelial' MR and is mediated by an imbalance of oxidative stress-modulating mechanisms. Therefore, MR antagonists may represent an attractive therapeutic strategy in the increasing population of obese patients to decrease vascular dysfunction and subsequent atherosclerotic complications.

  13. Evaluation of Energy Balance on Human Telomerase Reverse Transcriptase (hTERT) Alternative Splicing by Semi-quantitative RT-PCR in Human Umbilical Vein Endothelial Cells.

    Science.gov (United States)

    Behjati, Mohaddeseh; Hashemi, Mohammad; Kazemi, Mohammad; Salehi, Mansoor; Javanmard, Shaghayegh Haghjooy

    2017-01-01

    Decreased high-energy phosphate level is involved in endothelial cell injury and dysfunction. Reduced telomerase activity in endothelial cells in parallel with reduced energy levels might be due to altered direction of alternative splicing machine as a complication of depleted energy during the process of atherosclerosis. Isolated human umbilical vein endothelial cells (HUVECs) were treated for 24 hours by oligomycine (OM) and 2-deoxy glucose (2-DG). After 24 hours, the effect of energy depletion on telomerase splicing pattern was evaluated using RT-PCR. Indeed, in both treated and untargeted cells, nitric oxide (NO) and von Willebrand factor (vWF) were measured. ATP was depleted in treated cells by 43.9% compared with control group. We observed a slight decrease in NO levels ( P = 0.09) and vWF ( P = 0.395) in the setting of 49.36% ATP depletion. In both groups, no telomerase gene expression was seen. Telomerase and housekeeping gene expression were found in positive control group (colon cancer tissue) and sample tissue. The absence of telomerase gene expression in HUVECs might be due to the mortality of these cells or the low level of telomerase gene expression in these cells under normal circumstances.

  14. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Español Hyperglycemia (High Blood Glucose) Hyperglycemia is the technical term for high blood glucose (blood sugar). High ... We Are Research Leaders We Support Your Doctor Student Resources Patient Access to Research Research Resources Practice ...

  15. Prognostic Value of CD109+ Circulating Endothelial Cells in Recurrent Glioblastomas Treated with Bevacizumab and Irinotecan

    Science.gov (United States)

    Cuppini, Lucia; Calleri, Angelica; Bruzzone, Maria Grazia; Prodi, Elena; Anghileri, Elena; Pellegatta, Serena; Mancuso, Patrizia; Porrati, Paola; Di Stefano, Anna Luisa; Ceroni, Mauro; Bertolini, Francesco; Finocchiaro, Gaetano; Eoli, Marica

    2013-01-01

    Background Recent data suggest that circulating endothelial and progenitor cells (CECs and CEPs, respectively) may have predictive potential in cancer patients treated with bevacizumab, the antibody recognizing vascular endothelial growth factor (VEGF). Here we report on CECs and CEPs investigated in 68 patients affected by recurrent glioblastoma (rGBM) treated with bevacizumab and irinotecan and two Independent Datasets of rGBM patients respectively treated with bevacizumab alone (n=32, independent dataset A: IDA) and classical antiblastic chemotherapy (n=14, independent dataset B: IDB). Methods rGBM patients with KPS ≥50 were treated until progression, as defined by MRI with RANO criteria. CECs expressing CD109, a marker of tumor endothelial cells, as well as other CEC and CEP subtypes, were investigated by six-color flow cytometry. Results A baseline count of CD109+ CEC higher than 41.1/ml (1st quartile) was associated with increased progression free survival (PFS; 20 versus 9 weeks, P=0.008) and overall survival (OS; 32 versus 23 weeks, P=0.03). Longer PFS (25 versus 8 weeks, P=0.02) and OS (27 versus 17 weeks, P=0.03) were also confirmed in IDA with CD109+ CECs higher than 41.1/ml but not in IDB. Patients treated with bevacizumab with or without irinotecan that were free from MRI progression after two months of treatment had significant decrease of CD109+ CECs: median PFS was 19 weeks; median OS 29 weeks. The presence of two non-contiguous lesions (distant disease) at baseline was an independent predictor of shorter PFS and OS (P<0.001). Conclusions Data encourage further studies on the predictive potential of CD109+ CECs in GBM patients treated with bevacizumab. PMID:24069296

  16. Restoration of Impaired Metabolic Energy Balance (ATP Pool and Tube Formation Potential of Endothelial Cells under “high glucose”, Diabetic Conditions by the Bioinorganic Polymer Polyphosphate

    Directory of Open Access Journals (Sweden)

    Xiaohong Wang

    2017-11-01

    Full Text Available Micro-vascularization is a fast, energy-dependent process that is compromised by elevated glucose concentrations such as in diabetes mellitus disease. Here, we studied the effect of the physiological bioinorganic polymer, polyphosphate (polyP, on the reduced ATP content and impaired function of endothelial cells cultivated under “high glucose” (35 mM diabetes mellitus conditions concentrations. This high-energy biopolymer has been shown to provide a source of metabolic energy, stored in its phosphoanhydride bonds. We show that exposure of human umbilical vein endothelial cells (HUVEC cells to “high glucose” levels results in reduced cell viability, increased apoptotic cell death, and a decline in intracellular ATP level. As a consequence, the ability of HUVEC cells to form tube-like structures in the in vitro cell tube formation assay was almost completely abolished under “high glucose” conditions. Those cells were grown onto a physiological collagen scaffold (collagen/basement membrane extract. We demonstrate that these adverse effects of increased glucose levels can be reversed by administration of polyP to almost normal values. Using Na-polyP, complexed in a stoichiometric (molar ratio to Ca2+ ions and in the physiological concentration range between 30 and 300 µM, an almost complete restoration of the reduced ATP pool of cells exposed to “high glucose” was found, as well as a normalization of the number of apoptotic cells and energy-dependent tube formation. It is concluded that the adverse effects on endothelial cells caused by the metabolic energy imbalance at elevated glucose concentrations can be counterbalanced by polyP, potentially opening new strategies for treatment of the micro-vascular complications in diabetic patients.

  17. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Carbohydrate Counting Make Your Carbs Count Glycemic Index Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type ... Checking Your Blood Glucose A1C and eAG Hypoglycemia (Low blood glucose) Hyperglycemia (High blood glucose) Dawn Phenomenon ...

  18. MicroRNAs in Hyperglycemia Induced Endothelial Cell Dysfunction

    Directory of Open Access Journals (Sweden)

    Maskomani Silambarasan

    2016-04-01

    Full Text Available Hyperglycemia is closely associated with prediabetes and Type 2 Diabetes Mellitus. Hyperglycemia increases the risk of vascular complications such as diabetic retinopathy, diabetic nephropathy, peripheral vascular disease and cerebro/cardiovascular diseases. Under hyperglycemic conditions, the endothelial cells become dysfunctional. In this study, we investigated the miRNA expression changes in human umbilical vein endothelial cells exposed to different glucose concentrations (5, 10, 25 and 40 mM glucose and at various time intervals (6, 12, 24 and 48 h. miRNA microarray analyses showed that there is a correlation between hyperglycemia induced endothelial dysfunction and miRNA expression. In silico pathways analyses on the altered miRNA expression showed that the majority of the affected biological pathways appeared to be associated to endothelial cell dysfunction and apoptosis. We found the expression of ten miRNAs (miR-26a-5p, -26b-5p, 29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -140-5p, -192-5p, -221-3p and -320a to increase gradually with increasing concentration of glucose. These miRNAs were also found to be involved in endothelial dysfunction. At least seven of them, miR-29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -221-3p, -320a and -192-5p, can be correlated to endothelial cell apoptosis.

  19. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Your Carbs Count Glycemic Index Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type 1 Diabetes Get ... the technical term for high blood glucose (blood sugar). High blood glucose happens when the body has ...

  20. Comparative study of expression and activity of glucose transporters between stem cell-derived brain microvascular endothelial cells and hCMEC/D3 cells.

    Science.gov (United States)

    Al-Ahmad, Abraham J

    2017-10-01

    Glucose constitutes a major source of energy of mammalian brains. Glucose uptake at the blood-brain barrier (BBB) occurs through a facilitated glucose transport, through glucose transporter 1 (GLUT1), although other isoforms have been described at the BBB. Mutations in GLUT1 are associated with the GLUT1 deficiency syndrome, yet none of the current in vitro models of the human BBB maybe suited for modeling such a disorder. In this study, we investigated the expression of glucose transporters and glucose diffusion across brain microvascular endothelial cells (BMECs) derived from healthy patient-derived induced pluripotent stem cells (iPSCs). We investigated the expression of different glucose transporters at the BBB using immunocytochemistry and flow cytometry and measured glucose uptake and diffusion across BMEC monolayers obtained from two iPSC lines and from hCMEC/D3 cells. BMEC monolayers showed expression of several glucose transporters, in particular GLUT1, GLUT3, and GLUT4. Diffusion of glucose across the monolayers was mediated via a saturable transcellular mechanism and partially inhibited by pharmacological inhibitors. Taken together, our study suggests the presence of several glucose transporters isoforms at the human BBB and demonstrates the feasibility of modeling glucose across the BBB using patient-derived stem cells. Copyright © 2017 the American Physiological Society.

  1. THE CHALLENGE OF PD PATIENTS: GLUCOSE AND GLUCOSE DEGRADATION PRODUCTS IN PD SOLUTION

    Directory of Open Access Journals (Sweden)

    Yong-Lim Kim

    2012-06-01

    Full Text Available The main osmotic agent found in the peritoneal dialysis (PD solution is glucose. It has been of a wide use for great crystalloid osmotic power at a low concentration, simple metabolism, and excellent safety. On the other hand, anywhere between 60 to 80% of the glucose in the PD solution is absorbed - a 100 to 300 mg of daily glucose absorption. Once into the systemic circulation, glucose can be a cause for metabolic complications including obesity. Indeed, the diabetiform change observed in the peritoneal membrane in the long-term PD patients is believed attributable to the high-concentration glucose in the PD solution. The glucose absorbed from peritoneal cavity raises the risk of ‘glucose toxicity’, leading to insulin resistance and beta cell failure. Clinical similarity can be found in postprandial hyperglycemia, which is known to be associated with oxidative stress, endothelial dysfunction, NF-κb, and inflammation, affecting myocardial blood flow. Moreover, it is a proven independent risk factor of coronary artery disease in patients with type 2 diabetes, particularly of female gender. Though speculative yet, glucose toxicity might explain a higher mortality of PD patients after the first year compared with those on hemodialysis (more so in female, advanced-age patients with diabetes. Also included in the picture are glucose degradation products (GDPs generated along the course of heat sterilization or storage of the PD solution. They have been shown to induce apoptosis of peritoneal mesothelial cells, renal tubular epithelial cells, and endothelial cells, while spurring production of TGF-β and VEGF and facilitating epithelial mesenchymal transition. GDPs provide a stronger reactivity than glucose in the formation of AGEs, a known cause for microvascular complications and arteriosclerosis. Unfortunately, clinical studies using a low-GDP PD solution have provided mixed results on the residual renal function, peritonitis, peritoneal

  2. Endothelial protein C receptor in renal tubular epithelial cells and ...

    African Journals Online (AJOL)

    Jane

    2011-07-20

    Jul 20, 2011 ... Some factors such as high glucose, tumor necrosis factor–α and interleukin-1β can impact on ... a direct link to the reduction of mRNA levels in endothelial ..... can it improve insulin resistance and lower blood sugar, but it can ...

  3. Dual mechanisms of NF-κB inhibition in carnosol-treated endothelial cells

    International Nuclear Information System (INIS)

    Lian, K.-C.; Chuang, J.-J.; Hsieh, C.-W.; Wung, B.-S.; Huang, G.-D.; Jian, T.-Y.; Sun, Y.-W.

    2010-01-01

    The increased adhesion of monocytes to injured endothelial layers is a critical early event in atherogenesis. Under inflammatory conditions, there is increased expression of specific cell adhesion molecules on activated vascular endothelial cells, which increases monocyte adhesion. In our current study, we demonstrate a putative mechanism for the anti-inflammatory effects of carnosol, a diterpene derived from the herb rosemary. Our results show that both carnosol and rosemary essential oils inhibit the adhesion of TNFα-induced monocytes to endothelial cells and suppress the expression of ICAM-1 at the transcriptional level. Moreover, carnosol was found to exert its inhibitory effects by blocking the degradation of the inhibitory protein IκBα in short term pretreatments but not in 12 h pretreatments. Our data show that carnosol reduces IKK-β phosphorylation in pretreatments of less than 3 h. In TNFα-treated ECs, NF-κB nuclear translocation and transcriptional activity was abolished by up to 12 h of carnosol pretreatment and this was blocked by Nrf-2 siRNA. The long-term inhibitory effects of carnosol thus appear to be mediated through its induction of Nrf-2-related genes. The inhibition of ICAM-1 expression and p65 translocation is reversed by HO-1 siRNA. Carnosol also upregulates the Nrf-2-related glutathione synthase gene and thereby increases the GSH levels after 9 h of exposure. Treating ECs with a GSH synthesis inhibitor, BSO, blocks the inhibitory effects of carnosol. In addition, carnosol increases p65 glutathionylation. Hence, our present findings indicate that carnosol suppresses TNFα-induced singling pathways through the inhibition of IKK-β activity or the upregulation of HO-1 expression. The resulting GSH levels are dependent, however, on the length of the carnosol pretreatment period.

  4. Triglycerides as an early pathophysiological marker of endothelial dysfunction in nondiabetic women with a previous history of gestational diabetes.

    Science.gov (United States)

    Sokup, Alina; Góralczyk, Barbara; Góralczyk, Krzysztof; Rość, Danuta

    2012-02-01

    To investigate whether baseline triglyceride levels are associated with early glucose dysregulation and/or cardiovascular risk in women with a previous history of gestational diabetes. Prospective postpregnancy cohort study. Polish university hospitals. Participants included 125 women with previous gestational diabetes and 40 women with normal glucose regulation during pregnancy. All women were studied 2-24 months (mean 12 ± 10 months) after the index pregnancy. Women with previous gestational diabetes were divided into tertiles in accordance with baseline triglyceride levels. We assessed glucose regulation (oral glucose tolerance test), insulin resistance (homeostasis model assessment), markers of endothelial dysfunction (soluble: intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, tissue plasminogen activator antigen, von Willebrand factor antigen), fibrinolysis (plasminogen activator inhibitor antigen), inflammation (high-sensitivity C-reactive protein) and lipid levels. Women with previous gestational diabetes (78% normal glucose regulation, 22% impaired glucose tolerance) had a high cardiometabolic risk profile compared with control women (100% normal glucose regulation). Baseline triglycerides >0.83 mmol/l were associated with a higher prevalence of impaired glucose tolerance, higher high-sensitivity C-reactive protein and triglyceride/high-density lipoprotein-cholesterol ratio. Triglycerides >1.22 mmol/l were associated with higher body fat indexes, higher insulin resistance, higher levels of endothelial dysfunction biomarkers, higher plasminogen activator inhibitor antigen and dyslipidemia. Only E-selectin was independently associated with triglyceride levels. Baseline triglyceride levels are a cardiovascular risk marker as well as a pathophysiological parameter independently associated with endothelial dysfunction in nondiabetic women with previous gestational diabetes at 2-24 months after an index pregnancy. Normalization of

  5. [Valsartan inhibits angiotensin II-Notch signaling of mesangial cells induced by high glucose].

    Science.gov (United States)

    Yuan, Qin; Lyu, Chuan; Wu, Can; Lei, Sha; Shao, Ying; Wang, Qiuyue

    2016-01-01

    To explore the role of angiotensin II (Ang II)-Notch signaling in high glucose-induced secretion of extracellular matrix of rat mesangial cells (RMCs) and to further investigate the protective effect of valsartan (one of Ang II receptor blockers) on kidney. Subcultured RMCs were divided into groups as follows: normal glucose group (5.5 mmol/L glucose); high glucose group (30 mmol/L glucose); high concentration of mannitol as osmotic control group (5.5 mmol/L glucose and 24.5 mmol/L mannitol); normal glucose plus 1 μmol/L N-[N-(3, 5-difluorophenacetyl)-L-alanyl ]-S-phenylglycine t-butyl ester (DAPT) group; normal glucose plus (1, 5, 10) μmol/L valsartan group; high glucose plus 1 μmol/L DAPT group; high glucose plus (1, 5, 10) μmol/L valsartan group. Cells and supernatants were harvested after 12, 24 and 48 hours. Notch1 expression was examined by Western blotting. Secretion of transforming growth factor (TGF-β) and fibronectin (FN) were detected by ELISA. Compared to the normal glucose group, Notch1 expression was elevated in the high glucose group after 12 hours, and peaked at 24 hours. Besides, secretion of TGF-β and FN were much higher in the high glucose group than in the normal glucose group in a time-dependent manner. Compared to the untreated group, Notch1 expression decreased in a dose-dependent manner in the valsartan or DAPT treated group under high glucose after 24 hours. After pre-treatment by either valsartan or DAPT in the high glucose group, secretion of TGF-β and FN obviously decreased as compared to the untreated group. Hyperglycemia could stimulate activation of Notch signaling in cultured RMCs, which may increase secretion of downstream fibrotic factors such as TGF-β and FN. Valsartan may decrease the secretion of downstream FN in a dose-dependent manner via inhibiting AngII-Notch signaling.

  6. High-intensity interval exercise attenuates but does not eliminate endothelial dysfunction after a fast food meal.

    Science.gov (United States)

    Tucker, Wesley J; Sawyer, Brandon J; Jarrett, Catherine L; Bhammar, Dharini M; Ryder, Justin R; Angadi, Siddhartha S; Gaesser, Glenn A

    2018-02-01

    We investigated whether two different bouts of high-intensity interval exercise (HIIE) could attenuate postprandial endothelial dysfunction. Thirteen young (27 ± 1 yr), nonexercise-trained men underwent three randomized conditions: 1) four 4-min intervals at 85-95% of maximum heart rate separated by 3 min of active recovery (HIIE 4 × 4), 2) 16 1-min intervals at 85-95% of maximum heart rate separated by 1 min of active recovery (HIIE 16 × 1), and 3) sedentary control. HIIE was performed in the afternoon, ~18 h before the morning fast food meal (1,250 kcal, 63g of fat). Brachial artery flow-mediated dilation (FMD) was performed before HIIE ( baseline 1), during fasting before meal ingestion ( baseline 2), and 30 min, 2 h, and 4 h postprandial. Capillary glucose and triglycerides were assessed at fasting, 30 min, 1 h, 2 h, and 4 h (triglycerides only). Both HIIE protocols increased fasting FMD compared with control (HIIE 4 × 4: 6.1 ± 0.4%, HIIE 16 × 1: 6.3 ± 0.5%, and control: 5.1 ± 0.4%, P fast food meal can attenuate but not entirely eliminate postprandial decreases in FMD. This effect is not dependent on reductions in postprandial lipemia or glycemia. NEW & NOTEWORTHY Two similar high-intensity interval exercise (HIIE) protocols performed ∼18 h before ingestion of a high-energy fast food meal attenuated but did not entirely eliminate postprandial endothelial dysfunction in young men largely by improving fasting endothelial function. Both HIIE protocols produced essentially identical results, suggesting high reproducibility of HIIE effects.

  7. Effect of Functional Bread Rich in Potassium, γ-Aminobutyric Acid and Angiotensin-Converting Enzyme Inhibitors on Blood Pressure, Glucose Metabolism and Endothelial Function

    Science.gov (United States)

    Becerra-Tomás, Nerea; Guasch-Ferré, Marta; Quilez, Joan; Merino, Jordi; Ferré, Raimon; Díaz-López, Andrés; Bulló, Mònica; Hernández-Alonso, Pablo; Palau-Galindo, Antoni; Salas-Salvadó, Jordi

    2015-01-01

    Abstract Because it has been suggested that food rich in γ-aminobutyric acid (GABA) or angiotensin-converting enzyme inhibitor (ACEI) peptides have beneficial effects on blood pressure (BP) and other cardiovascular risk factors, we tested the effects of low-sodium bread, but rich in potassium, GABA, and ACEI peptides on 24-hour BP, glucose metabolism, and endothelial function. A randomized, double-blind, crossover trial was conducted in 30 patients with pre or mild-to-moderate hypertension, comparing three 4-week nutritional interventions separated by 2-week washout periods. Patients were randomly assigned to consume 120 g/day of 1 of the 3 types of bread for each nutritional intervention: conventional wheat bread (CB), low-sodium wheat bread enriched in potassium (LSB), and low-sodium wheat bread rich in potassium, GABA, and ACEI peptides (LSB + G). For each period, 24-hour BP measurements, in vivo endothelial function, and biochemical samples were obtained. After LSB + G consumption, 24-hour ambulatory BP underwent a nonsignificant greater reduction than after the consumption of CB and LSB (0.26 mm Hg in systolic BP and −0.63 mm Hg in diastolic BP for CB; −0.71 mm Hg in systolic BP and −1.08 mm Hg in diastolic BP for LSB; and −0.75 mm Hg in systolic BP and −2.12 mm Hg in diastolic BP for LSB + G, respectively). Diastolic BP at rest decreased significantly during the LSB + G intervention, although there were no significant differences in changes between interventions. There were no significant differences between interventions in terms of changes in in vivo endothelial function, glucose metabolism, and peripheral inflammatory parameters. Compared with the consumption of CB or LSB, no greater beneficial effects on 24-hour BP, endothelial function, or glucose metabolism were demonstrated after the consumption of LSB + G in a population with pre or mild-to-moderate hypertension. Further studies are warranted to clarify the

  8. ALK5 inhibition maintains islet endothelial cell survival but does not enhance islet graft revascularisation or function.

    Science.gov (United States)

    King, A J F; Clarkin, C E; Austin, A L F; Ajram, L; Dhunna, J K; Jamil, M O; Ditta, S I; Ibrahim, S; Raza, Z; Jones, P M

    2015-01-01

    Islet transplantation is a potential treatment for Type 1 diabetes but long term graft function is suboptimal. The rich supply of intraislet endothelial cells diminishes rapidly after islet isolation and culture, which affects the revascularisation rate of islets after transplantation. The ALK5 pathway inhibits endothelial cell proliferation and thus inhibiting ALK5 is a potential target for improving endothelial cell survival. The aim of the study was to establish whether ALK5 inhibition prevents the loss of intraislet endothelial cells during islet culture and thus improves the functional survival of transplanted islets by enhancing their subsequent revascularisation after implantation. Islets were cultured for 48 h in the absence or presence of 2 different ALK inhibitors: SB-431542 or A-83-01. Their vascular density after culture was analysed using immunohistochemistry. Islets pre-cultured with the ALK5 inhibitors were implanted into streptozotocin-diabetic mice for either 3 or 7 days and blood glucose concentrations were monitored and vascular densities of the grafts were analysed. Islets cultured with ALK5 inhibitors had higher vascular densities than control-cultured islets. Three days after implantation, endothelial cell numbers in islet grafts were minimal, irrespective of treatment during culture. Seven days after implantation, endothelial cells were evident within the islet grafts but there was no difference between control-cultured islets and islets pre-treated with an ALK5 inhibitor. Blood glucose concentrations were no different between the treatment groups. In conclusion, inhibition of ALK5 improved intraislet endothelial cell numbers after islet culture, but this effect was lost in the early post-transplantation period. © Georg Thieme Verlag KG Stuttgart · New York.

  9. The protective role of isorhamnetin on human brain microvascular endothelial cells from cytotoxicity induced by methylglyoxal and oxygen-glucose deprivation.

    Science.gov (United States)

    Li, Wenlu; Chen, Zhigang; Yan, Min; He, Ping; Chen, Zhong; Dai, Haibin

    2016-02-01

    As the first target of stroke, cerebral endothelial cells play a key role in brain vascular repair and maintenance, and their function is impeded in diabetes. Methylglyoxal (MGO), a reactive dicarbonyl produced during glucose metabolism, accumulates in diabetic patients. MGO and MGO-induced advanced glycation end-products (AGEs) could ameliorate stroke-induced brain vascular damage, closely related with ECs dysfunction. Using MGO plus oxygen-glucose deprivation (OGD) to mimic diabetic stroke, we reported the protective effect of isorhamnetin on OGD-induced cytotoxicity after MGO treatment on primary human brain microvascular endothelial cells (HBMEC) and explored the underlying mechanisms. Treatment of MGO for 24 h significantly enhanced 3-h OGD-induced HBMEC toxic effect, which was inhibited by pretreatment of isorhamnetin (100 μmol/L). Moreover, the protective effect of isorhamnetin is multiple function dependent, which includes anti-inflammation, anti-oxidative stress and anti-apoptosis effects. Besides its well-known inhibition on the mitochondria-dependent or intrinsic apoptotic pathway, isorhamnetin also reduced activation of the extrinsic apoptotic pathway, as characterized by the decreased expression and activity of caspase 3 and caspase 8. Furthermore, pretreatment with isorhamnetin specifically inhibited FAS/FASL expression and suppressed nuclear factor-kappa B nuclear translocation. Taken together, our results indicated that isorhamnetin protected against OGD-induced cytotoxicity after MGO treatment in cultured HBMEC due to its multiple protective effects and could inhibit Fas-mediated extrinsic apoptosis. Therefore, isorhamnetin is a promising reagent for the treatment of hyperglycemia and ischemia-induced cerebral vascular degeneration. A proposed model of the potential protective mechanism of isorhamnetin, a metabolite of quercetin, on methylglyoxal (MGO) treatment plus oxygen-glucose deprivation (OGD) exposure-induced cytotoxicity in cultured human

  10. Tetrahydrobiopterin Has a Glucose-Lowering Effect by Suppressing Hepatic Gluconeogenesis in an Endothelial Nitric Oxide Synthase–Dependent Manner in Diabetic Mice

    Science.gov (United States)

    Abudukadier, Abulizi; Fujita, Yoshihito; Obara, Akio; Ohashi, Akiko; Fukushima, Toru; Sato, Yuichi; Ogura, Masahito; Nakamura, Yasuhiko; Fujimoto, Shimpei; Hosokawa, Masaya; Hasegawa, Hiroyuki; Inagaki, Nobuya

    2013-01-01

    Endothelial nitric oxide synthase (eNOS) dysfunction induces insulin resistance and glucose intolerance. Tetrahydrobiopterin (BH4) is an essential cofactor of eNOS that regulates eNOS activity. In the diabetic state, BH4 is oxidized to 7,8-dihydrobiopterin, which leads to eNOS dysfunction owing to eNOS uncoupling. The current study investigates the effects of BH4 on glucose metabolism and insulin sensitivity in diabetic mice. Single administration of BH4 lowered fasting blood glucose levels in wild-type mice with streptozotocin (STZ)-induced diabetes and alleviated eNOS dysfunction by increasing eNOS dimerization in the liver of these mice. Liver has a critical role in glucose-lowering effects of BH4 through suppression of hepatic gluconeogenesis. BH4 activated AMP kinase (AMPK), and the suppressing effect of BH4 on gluconeogenesis was AMPK-dependent. In addition, the glucose-lowering effect and activation of AMPK by BH4 did not appear in mice with STZ-induced diabetes lacking eNOS. Consecutive administration of BH4 in ob/ob mice ameliorated glucose intolerance and insulin resistance. Taken together, BH4 suppresses hepatic gluconeogenesis in an eNOS-dependent manner, and BH4 has a glucose-lowering effect as well as an insulin-sensitizing effect in diabetic mice. BH4 has potential in the treatment of type 2 diabetes. PMID:23649519

  11. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day ... DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & Care Blood Glucose Testing ...

  12. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... blood glucose High levels of sugar in the urine Frequent urination Increased thirst Part of managing your ... glucose is above 240 mg/dl, check your urine for ketones. If you have ketones, do not ...

  13. Effects of Acute Active Video Games on Endothelial Function Following a High-Fat Meal in Overweight Adolescents.

    Science.gov (United States)

    Park, Soo Hyun; Yoon, Eun Sun; Lee, Yong Hee; Kim, Chul-Ho; Bunsawat, Kanokwan; Heffernan, Kevin S; Fernall, Bo; Jae, Sae Young

    2015-06-01

    We tested the hypothesis that an active video game following a high-fat meal would partially prevent the unfavorable effect of a high-fat meal on vascular function in overweight adolescents. Twenty-four overweight adolescents were randomized to either a 60-minute active video game (AVG) group (n = 12) or seated rest (SR) as a control group (n = 12) after a high-fat meal. Blood parameters were measured, and vascular function was measured using brachial artery flow-mediated dilation (FMD) at baseline and 3 hours after a high-fat meal. No significant interaction was found in any blood parameter. A high-fat meal significantly increased blood triglyceride and glucose concentrations in both groups in a similar manner. Brachial artery FMD significantly decreased in the SR group (13.8 ± 3.2% to 11.8 ± 2.5), but increased in the AVG group (11.4 ± 4.0% to 13.3 ± 3.5), with a significant interaction (P = .034). These findings show that an active video game attenuated high-fat meal-induced endothelial dysfunction. This suggests that an active video game may have a cardioprotective effect on endothelial function in overweight adolescents when exposed to a high-fat meal.

  14. Effects of elevated glucose concentration on cultured bovine retinal endothelial (BRE) cells

    International Nuclear Information System (INIS)

    Capetandes, A.; Gerritsen, M.E.

    1986-01-01

    Salient clinical features of diabetic retinopathy include capillary microaneurysm and neovascularization, which progress with the severity of the disease. It has been suggested that exposure of the retinal vascular cells to high glucose concentrations may play a causative role in the retinopathy. In the present study, the effects of variant media glucose concentrations on BRE cell growth were determined. Normal growth curves were obtained with glucose concentrations of 100, 450 and 600 mg%, but the replication rate was decreased with 600 mg%. To determine if elevated glucose concentrations also altered DNA synthesis, BRE cells cultivated with 100 and 600 mg% glucose demonstrated increased thymidine uptake and total DNA content compared to the 100 mg% group. Furthermore, vacuolation and increased cell diameter occurred in BRE cells cultivated 600 mg% compared to 100 mg% glucose. In conclusion, increases in media glucose concentrations result in a decreased cellular replication rate, increased DNA synthesis and increased cell diameter during the log phase of growth

  15. O-hexadecyl-dextran entrapped berberine nanoparticles abrogate high glucose stress induced apoptosis in primary rat hepatocytes.

    Directory of Open Access Journals (Sweden)

    Radhika Kapoor

    Full Text Available Nanotized phytochemicals are being explored by researchers for promoting their uptake and effectiveness at lower concentrations. In this study, O-hexadecyl-dextran entrapped berberine chloride nanoparticles (BC-HDD NPs were prepared, and evaluated for their cytoprotective efficacy in high glucose stressed primary hepatocytes and the results obtained compared with bulk berberine chloride (BBR treatment. The nanotized formulation treated primary hepatocytes that were exposed to high glucose (40 mM, showed increased viability compared to the bulk BBR treated cells. BC-HDD NPs reduced the ROS generation by ∼ 3.5 fold during co-treatment, prevented GSH depletion by ∼ 1.6 fold, reduced NO formation by ∼ 5 fold and significantly prevented decline in SOD activity in stressed cells. Lipid peroxidation was also prevented by ∼ 1.9 fold in the presence of these NPs confirming the antioxidant capacity of the formulation. High glucose stress increased Bax/Bcl2 ratio followed by mitochondrial depolarization and activation of caspase-9/-3 confirming involvement of mitochondrial pathway of apoptosis in the exposed cells. Co- and post-treatment of BC-HDD NPs prevented depolarization of mitochondrial membrane, reduced Bax/Bcl2 ratio and prevented externalization of phosphatidyl-serine confirming their anti-apoptotic capacity in those cells. Sub-G1 phase apparent in high glucose stressed cells was not seen in BC-HDD NPs treated cells. The present study reveals that BC-HDD NPs at ∼ 20 fold lower concentration are as effective as BBR in preventing high glucose induced oxidative stress, mitochondrial depolarization and downstream events of apoptotic cell death.

  16. High Glucose Represses hERG K+ Channel Expression through Trafficking Inhibition

    Directory of Open Access Journals (Sweden)

    Yuan-Qi Shi

    2015-08-01

    Full Text Available Background/Aims: Abnormal QT prolongation is the most prominent cardiac electrical disturbance in patients with diabetes mellitus (DM. It is well known that the human ether-ago-go-related gene (hERG controls the rapid delayed rectifier K+ current (IKr in cardiac cells. The expression of the hERG channel is severely down-regulated in diabetic hearts, and this down-regulation is a critical contributor to the slowing of repolarization and QT prolongation. However, the intracellular mechanisms underlying the diabetes-induced hERG deficiency remain unknown. Methods: The expression of the hERG channel was assessed via western blot analysis, and the hERG current was detected with a patch-clamp technique. Results: The results of our study revealed that the expression of the hERG protein and the hERG current were substantially decreased in high-glucose-treated hERG-HEK cells. Moreover, we demonstrated that the high-glucose-mediated damage to the hERG channel depended on the down-regulation of protein levels but not the alteration of channel kinetics. These discoveries indicated that high glucose likely disrupted hERG channel trafficking. From the western blot and immunoprecipitation analyses, we found that high glucose induced trafficking inhibition through an effect on the expression of Hsp90 and its interaction with hERG. Furthermore, the high-glucose-induced inhibition of hERG channel trafficking could activate the unfolded protein response (UPR by up-regulating the expression levels of activating transcription factor-6 (ATF-6 and the ER chaperone protein calnexin. In addition, we demonstrated that 100 nM insulin up-regulated the expression of the hERG channel and rescued the hERG channel repression caused by high glucose. Conclusion: The results of our study provide the first evidence of a high-glucose-induced hERG channel deficiency resulting from the inhibition of channel trafficking. Furthermore, insulin promotes the expression of the hERG channel

  17. BIGH3 protein and macrophages in retinal endothelial cell apoptosis.

    Science.gov (United States)

    Mondragon, Albert A; Betts-Obregon, Brandi S; Moritz, Robert J; Parvathaneni, Kalpana; Navarro, Mary M; Kim, Hong Seok; Lee, Chi Fung; LeBaron, Richard G; Asmis, Reto; Tsin, Andrew T

    2015-01-01

    Diabetes is a pandemic disease with a higher occurrence in minority populations. The molecular mechanism to initiate diabetes-associated retinal angiogenesis remains largely unknown. We propose an inflammatory pathway of diabetic retinopathy in which macrophages in the diabetic eye provide TGFβ to retinal endothelial cells (REC) in the retinal microvasculature. In response to TGFβ, REC synthesize and secrete a pro-apoptotic BIGH3 (TGFβ-Induced Gene Human Clone 3) protein, which acts in an autocrine loop to induce REC apoptosis. Rhesus monkey retinal endothelial cells (RhREC) were treated with dMCM (cell media of macrophages treated with high glucose and LDL) and assayed for apoptosis (TUNEL), BIGH3 mRNA (qPCR), and protein (Western blots) expressions. Cells were also treated with ΤGFβ1 and 2 for BIGH3 mRNA and protein expression. Inhibition assays were carried out using antibodies for TGFβ1 and for BIGH3 to block apoptosis and mRNA expression. BIGH3 in cultured RhREC cells were identified by immunohistochemistry (IHC). Distribution of BIGH3 and macrophages in the diabetic mouse retina was examined with IHC. RhRECs treated with dMCM or TGFβ showed a significant increase in apoptosis and BIGH3 protein expression. Recombinant BIGH3 added to RhREC culture medium led to a dose-dependent increase in apoptosis. Antibodies (Ab) directed against BIGH3 and TGFβ, as well as TGFβ receptor blocker resulted in a significant reduction in apoptosis induced by either dMCM, TGFβ or BIGH3. IHC showed that cultured RhREC constitutively expressed BIGH3. Macrophage and BIGH3 protein were co-localized to the inner retina of the diabetic mouse eye. Our results support a novel inflammatory pathway for diabetic retinopathy. This pathway is initiated by TGFβ released from macrophages, which promotes synthesis and release of BIGH3 protein by REC and REC apoptosis.

  18. Neuroprotective effects of ginsenoside Rb1 on high glucose-induced neurotoxicity in primary cultured rat hippocampal neurons.

    Science.gov (United States)

    Liu, Di; Zhang, Hong; Gu, Wenjuan; Liu, Yuqin; Zhang, Mengren

    2013-01-01

    Ginsenoside Rb1 is one of the main active principles in traditional herb ginseng and has been reported to have a wide variety of neuroprotective effects. Endoplasmic reticulum (ER) stress has been implicated in neurodegenerative diseases, so the present study aimed to observe the effects of ginsenoside Rb1 on ER stress signaling pathways in high glucose-treated hippocampal neurons. The results from MTT, TUNEL labeling and Annexin V-FITC/PI/Hoechst assays showed that incubating neurons with 50 mM high glucose for 72 h decreased cell viability and increased the number of apoptotic cells whereas treating neurons with 1 μM Rb1 for 72 h protected the neurons against high glucose-induced cell damage. Further molecular mechanism study demonstrated that Rb1 suppressed the activation of ER stress-associated proteins including protein kinase RNA (PKR)-like ER kinase (PERK) and C/EBP homology protein (CHOP) and downregulation of Bcl-2 induced by high glucose. Moreover, Rb1 inhibited both the elevation of intracellular reactive oxygen species (ROS) and the disruption of mitochondrial membrane potential induced by high glucose. In addition, the high glucose-induced cell apoptosis, activation of ER stress, ROS accumulation and mitochondrial dysfunction can also be attenuated by the inhibitor of ER stress 4-phenylbutyric acid (4-PBA) and anti-oxidant N-acetylcysteine(NAC). In conclusion, these results suggest that Rb1 may protect neurons against high glucose-induced cell injury through inhibiting CHOP signaling pathway as well as oxidative stress and mitochondrial dysfunction.

  19. Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

    Directory of Open Access Journals (Sweden)

    W Zhao

    2009-03-01

    Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p less than 0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

  20. Induction stage-dependent expression of vascular endothelial growth factor and aquaporin-1 in diethylstilbestrol-treated rat pituitary

    Directory of Open Access Journals (Sweden)

    Z Wang

    2009-03-01

    Full Text Available The anterior pituitary gland undergoes tumourigenic changes in response to oestrogen treatment in several breeds of rats. We administered diethylstilbestrol (DES to female Wistar rats and assessed whether the expression of vascular endothelial growth factor (VEGF and aquaporin-1 (AQP-1 was altered at different time points following DES administration. In vivo magnetic resonance imaging (MRI scans showed that the mass index corresponding to the mid-sagittal area of DES-treated pituitary was significantly higher than the vehicle-controlled pituitary (p<0.01 at three specific time points, accompanied by a significant reduction in body weight. Haematoxylin and eosin (HE staining and immunohistochemical analysis demonstrated that during early stages of induction, DES increased cell proliferation and sprouting of endothelial cells, and VEGF expression transitioned from a vessel-surrounding pattern to a diffuse pattern. During later stages, angiogenesis was predominant, and VEGF expression decreased. In contrast to the early abundant expression of VEGF, endothelial expression of AQP- 1 increased during later stages. Our data indicated a dynamic scenario of biological alterations in DES-treated pituitary tissue, in which VEGF and AQP-1 exert their functions at different stages of induction, and we provide novel insights into understanding oestrogen-related tumourigenesis in the anterior pituitary gland.

  1. Endothelial RIG-I activation impairs endothelial function

    International Nuclear Information System (INIS)

    Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

    2012-01-01

    Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  2. Effect of propionyl-L-carnitine on human endothelial cells

    NARCIS (Netherlands)

    Hinsbergh, V.W.M. van; Scheffer, M.A.

    1991-01-01

    A possible protective effect of propionyl-L-carnitine on human endothelial cells was studied both under basal culture conditions and in the presence of agents capable of influencing oxidative damage, such as glucose/glucose oxidase and oxidized low-density lipoproteins. Propionyl-L-carnitine had no

  3. Northern contaminant mixtures induced morphological and functional changes in human coronary artery endothelial cells under culture conditions typifying high fat/sugar diet and ethanol exposure.

    Science.gov (United States)

    Florian, Maria; Yan, Jin; Ulhaq, Saad; Coughlan, Melanie; Laziyan, Mahemuti; Willmore, William; Jin, Xiaolei

    2013-11-16

    It has been reported that Northern populations are exposed to mixtures of various environmental contaminants unique to the Arctic (Northern contaminant mixtures - NCM) at a large range of concentrations, depending on their geological location, age, lifestyle and dietary habits. To determine if these contaminants may contribute to a cardiovascular health risk, especially when combined with a high fat and sugar diet and ethanol exposure, we treated human coronary artery endothelial cells (HCAEC) with two mixtures of 4 organic (NCM1) or 22 organic and inorganic (NCM2) chemicals detected in Northerners' blood during 2004-2005 in the presence or absence of low-density lipoprotein (1.5mg/ml), very-low-density lipoprotein (1.0mg/ml) and glucose (10mmol/L) (LVG), and in the absence or presence of 0.1% ethanol. After 24h of exposure, cell morphology and markers of cytotoxicity and endothelial function were examined. NCM1 treatment did not affect cell viability, but increased cell size, disrupted cell membrane integrity, and decreased cell density, uptake of small peptides, release of endothelin-1 (ET-1) and plasminogen activator inhibitor (PAI), while causing no changes in endothelial nitric oxide synthase (eNOS) protein expression and nitric oxide (NO) release. In contrast, NCM2 decreased cell viability, total protein yield, uptake of small peptides, eNOS protein expression, and NO release and caused membrane damage, but caused no changes in the secretion of ET-1, prostacyclin and PAI. The presence of LVG and/or alcohol did or did not influence the effects of NCM1 or NCM2 depending on the endpoint and the mixture examined. These results suggested that the effects of one or one group of contaminants may be altered by the presence of other contaminants, and that with or without the interaction of high fat and sugar diet and/or ethanol exposure, NCMs at the concentrations used caused endothelial dysfunction in vitro. It remains to be investigated if these effects of NCMs also

  4. Porphyromonas gingivalis Differentially Modulates Cell Death Profile in Ox-LDL and TNF-α Pre-Treated Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Isaac Maximiliano Bugueno

    Full Text Available Clinical studies demonstrated a potential link between atherosclerosis and periodontitis. Porphyromonas gingivalis (Pg, one of the main periodontal pathogen, has been associated to atheromatous plaque worsening. However, synergism between infection and other endothelial stressors such as oxidized-LDL or TNF-α especially on endothelial cell (EC death has not been investigated. This study aims to assess the role of Pg on EC death in an inflammatory context and to determine potential molecular pathways involved.Human umbilical vein ECs (HUVECs were infected with Pg (MOI 100 or stimulated by its lipopolysaccharide (Pg-LPS (1μg/ml for 24 to 48 hours. Cell viability was measured with AlamarBlue test, type of cell death induced was assessed using Annexin V/propidium iodide staining. mRNA expression regarding caspase-1, -3, -9, Bcl-2, Bax-1 and Apaf-1 has been evaluated with RT-qPCR. Caspases enzymatic activity and concentration of APAF-1 protein were evaluated to confirm mRNA results.Pg infection and Pg-LPS stimulation induced EC death. A cumulative effect has been observed in Ox-LDL pre-treated ECs infected or stimulated. This effect was not observed in TNF-α pre-treated cells. Pg infection promotes EC necrosis, however, in infected Ox-LDL pre-treated ECs, apoptosis was promoted. This effect was not observed in TNF-α pre-treated cells highlighting specificity of molecular pathways activated. Regarding mRNA expression, Pg increased expression of pro-apoptotic genes including caspases-1,-3,-9, Bax-1 and decreased expression of anti-apoptotic Bcl-2. In Ox-LDL pre-treated ECs, Pg increased significantly the expression of Apaf-1. These results were confirmed at the protein level.This study contributes to demonstrate that Pg and its Pg-LPS could exacerbate Ox-LDL and TNF-α induced endothelial injury through increase of EC death. Interestingly, molecular pathways are differentially modulated by the infection in function of the pre-stimulation.

  5. Endothelial RIG-I activation impairs endothelial function

    Energy Technology Data Exchange (ETDEWEB)

    Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  6. Expression of inducible nitric oxide synthase, caspase-3 and production of reactive oxygen intermediate on endothelial cells culture (HUVECs treated with P. falciparum infected erythrocytes and tumour necrosis factor-α

    Directory of Open Access Journals (Sweden)

    Loeki E. Fitri

    2006-09-01

    Full Text Available Cytoadherence of P. falciparum infected erythrocytes on endothelial cells is a key factor in development of severe malaria. This process may associated with the activation of local immune that was enhanced by tumour necrosis factor-α (TNF-α. This study was conducted to see the influence of P.falciparum infected erythrocytes cytoadherence and TNF-α treatment in inducing endothelial cells activation in vitro. inducible nitric oxide synthase (iNOS and caspase-3 expression, also reactive oxygen intermediate (ROI production were used as parameters. An Experimental laboratory study had been done to observe endothelial cells activation (HUVECs after treatment with TNF-α for 20 hours or P. falciparum infected erythrocytes for 1 hour or both of them. Normal endothelial cells culture had been used as a control. Using immunocytochemistry local immune activation of endothelial cells was determined by iNOS and caspase-3 expression. Nitro Blue Tetrazolium reduction-assay was conducted to see the ROI production semi quantitatively. inducible nitric oxide synthase expression only found on endothelial cells culture treated with P. falciparum infected erythrocytes or both P. falciparum infected erythrocytes and TNF-α. Caspase-3 expression found slightly on normal endothelial cells culture. This expression increased significantly on endothelial cells culture treated with both P.falciparum infected erythrocytes and TNF-α (p=0.000. The normal endothelial cells release low level of ROI in the presence of non-specific trigger, PMA. In the presence of P. falciparum infected erythrocytes or TNF-α or both of them, some cells showed medium to high levels of ROI. Cytoadherence of P. falciparum infected erythrocytes and TNF α treatment on endothelial cells can induce activation of local immune marked by increase inducible nitric oxide synthase and release of free radicals that cause cell damage. (Med J Indones 2006; 15:151-6 Keywords: P.falciparum ,HUVECs, TNF-α, i

  7. Changes in hippocampal synaptic functions and protein expression in monosodium glutamate-treated obese mice during development of glucose intolerance.

    Science.gov (United States)

    Sasaki-Hamada, Sachie; Hojo, Yuki; Koyama, Hajime; Otsuka, Hayuma; Oka, Jun-Ichiro

    2015-05-01

    Glucose is the sole neural fuel for the brain and is essential for cognitive function. Abnormalities in glucose tolerance may be associated with impairments in cognitive function. Experimental obese model mice can be generated by an intraperitoneal injection of monosodium glutamate (MSG; 2 mg/g) once a day for 5 days from 1 day after birth. MSG-treated mice have been shown to develop glucose intolerance and exhibit chronic neuroendocrine dysfunction associated with marked cognitive malfunctions at 28-29  weeks old. Although hippocampal synaptic plasticity is impaired in MSG-treated mice, changes in synaptic transmission remain unknown. Here, we investigated whether glucose intolerance influenced cognitive function, synaptic properties and protein expression in the hippocampus. We demonstrated that MSG-treated mice developed glucose intolerance due to an impairment in the effectiveness of insulin actions, and showed cognitive impairments in the Y-maze test. Moreover, long-term potentiation (LTP) at Schaffer collateral-CA1 pyramidal synapses in hippocampal slices was impaired, and the relationship between the slope of extracellular field excitatory postsynaptic potential and stimulus intensity of synaptic transmission was weaker in MSG-treated mice. The protein levels of vesicular glutamate transporter 1 and GluA1 glutamate receptor subunits decreased in the CA1 region of MSG-treated mice. These results suggest that deficits in glutamatergic presynapses as well as postsynapses lead to impaired synaptic plasticity in MSG-treated mice during the development of glucose intolerance, though it remains unknown whether impaired LTP is due to altered inhibitory transmission. It may be important to examine changes in glucose tolerance in order to prevent cognitive malfunctions associated with diabetes. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  8. The effect of chronic heart failure and type 2 diabetes on insulin-stimulated endothelial function is similar and additive

    DEFF Research Database (Denmark)

    Falskov, Britt; Hermann, Thomas Steffen; Rask-Madsen, Christian

    2011-01-01

    AIM: Chronic heart failure is associated with endothelial dysfunction and insulin resistance. The aim of this investigation was to study insulin-stimulated endothelial function and glucose uptake in skeletal muscles in patients with heart failure in comparison to patients with type 2 diabetes. ME...... in similar vascular insulin resistance and reduced muscular insulin-stimulated glucose uptake. The effects of systolic heart failure and type 2 diabetes appear to be additive.......AIM: Chronic heart failure is associated with endothelial dysfunction and insulin resistance. The aim of this investigation was to study insulin-stimulated endothelial function and glucose uptake in skeletal muscles in patients with heart failure in comparison to patients with type 2 diabetes...

  9. A small population of liver endothelial cells undergoes endothelial-to-mesenchymal transition in response to chronic liver injury.

    Science.gov (United States)

    Ribera, Jordi; Pauta, Montse; Melgar-Lesmes, Pedro; Córdoba, Bernat; Bosch, Anna; Calvo, Maria; Rodrigo-Torres, Daniel; Sancho-Bru, Pau; Mira, Aurea; Jiménez, Wladimiro; Morales-Ruiz, Manuel

    2017-11-01

    Rising evidence points to endothelial-to-mesenchymal transition (EndMT) as a significant source of the mesenchymal cell population in fibrotic diseases. In this context, we hypothesized that liver endothelial cells undergo EndMT during fibrosis progression. Cirrhosis in mice was induced by CCl 4 A transgenic mouse expressing a red fluorescent protein reporter under the control of Tie2 promoter (Tie2-tdTomato) was used to trace the acquisition of EndMT. Sinusoidal vascular connectivity was evaluated by intravital microscopy and high-resolution three-dimensional confocal microscopy. A modest but significant fraction of liver endothelial cells from both cirrhotic patients and CCl 4 -treated Tie2-tdTomato mice acquired an EndMT phenotype characterized by the coexpression of CD31 and α-smooth muscle actin, compared with noncirrhotic livers. Bone morphogenetic protein-7 (BMP-7) inhibited the acquisition of EndMT induced by transforming growth factor-β1 (TGF-β1) treatment in cultured primary mouse liver endothelial cells from control mice. EndMT was also reduced significantly in vivo in cirrhotic Tie2-tdTomato mice treated intraperitoneally with BMP-7 compared with untreated mice (1.9 ± 0.2 vs. 3.8 ± 0.3%, respectively; P livers correlated with a significant decrease in liver fibrosis ( P livers in both animal models and patients. BMP-7 treatment decreases the occurrence of the EndMT phenotype and has a positive impact on the severity of disease by reducing fibrosis and sinusoidal vascular disorganization. NEW & NOTEWORTHY A subpopulation of liver endothelial cells from cirrhotic patients and mice with liver fibrosis undergoes endothelial-to-mesenchymal transition. Liver endothelial cells from healthy mice could transition into a mesenchymal phenotype in culture in response to TGF-β1 treatment. Fibrotic livers treated chronically with BMP-7 showed lower EndMT acquisition, reduced fibrosis, and improved vascular organization. Copyright © 2017 the American

  10. Myeloid-Cell-Derived VEGF Maintains Brain Glucose Uptake and Limits Cognitive Impairment in Obesity.

    Science.gov (United States)

    Jais, Alexander; Solas, Maite; Backes, Heiko; Chaurasia, Bhagirath; Kleinridders, André; Theurich, Sebastian; Mauer, Jan; Steculorum, Sophie M; Hampel, Brigitte; Goldau, Julia; Alber, Jens; Förster, Carola Y; Eming, Sabine A; Schwaninger, Markus; Ferrara, Napoleone; Karsenty, Gerard; Brüning, Jens C

    2016-05-05

    High-fat diet (HFD) feeding induces rapid reprogramming of systemic metabolism. Here, we demonstrate that HFD feeding of mice downregulates glucose transporter (GLUT)-1 expression in blood-brain barrier (BBB) vascular endothelial cells (BECs) and reduces brain glucose uptake. Upon prolonged HFD feeding, GLUT1 expression is restored, which is paralleled by increased expression of vascular endothelial growth factor (VEGF) in macrophages at the BBB. In turn, inducible reduction of GLUT1 expression specifically in BECs reduces brain glucose uptake and increases VEGF serum concentrations in lean mice. Conversely, myeloid-cell-specific deletion of VEGF in VEGF(Δmyel) mice impairs BBB-GLUT1 expression, brain glucose uptake, and memory formation in obese, but not in lean mice. Moreover, obese VEGF(Δmyel) mice exhibit exaggerated progression of cognitive decline and neuroinflammation on an Alzheimer's disease background. These experiments reveal that transient, HFD-elicited reduction of brain glucose uptake initiates a compensatory increase of VEGF production and assign obesity-associated macrophage activation a homeostatic role to restore cerebral glucose metabolism, preserve cognitive function, and limit neurodegeneration in obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Hyperglycemia (High Blood Glucose)

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  12. Cigarette smoke extract counteracts atheroprotective effects of high laminar flow on endothelial function

    Directory of Open Access Journals (Sweden)

    Sindy Giebe

    2017-08-01

    Full Text Available Tobacco smoking and hemodynamic forces are key stimuli in the development of endothelial dysfunction and atherosclerosis. High laminar flow has an atheroprotective effect on the endothelium and leads to a reduced response of endothelial cells to cardiovascular risk factors compared to regions with disturbed or low laminar flow. We hypothesize that the atheroprotective effect of high laminar flow could delay the development of endothelial dysfunction caused by cigarette smoking. Primary human endothelial cells were stimulated with increasing dosages of aqueous cigarette smoke extract (CSEaq. CSEaq reduced cell viability in a dose-dependent manner. The main mediator of cellular adaption to oxidative stress, nuclear factor erythroid 2-related factor 2 (NRF2 and its target genes heme oxygenase (decycling 1 (HMOX1 or NAD(PH quinone dehydrogenase 1 (NQO1 were strongly increased by CSEaq in a dose-dependent manner. High laminar flow induced elongation of endothelial cells in the direction of flow, activated the AKT/eNOS pathway, increased eNOS expression, phosphorylation and NO release. These increases were inhibited by CSEaq. Pro-inflammatory adhesion molecules intercellular adhesion molecule-1 (ICAM1, vascular cell adhesion molecule-1 (VCAM1, selectin E (SELE and chemokine (C-C motif ligand 2 (CCL2/MCP-1 were increased by CSEaq. Low laminar flow induced VCAM1 and SELE compared to high laminar flow. High laminar flow improved endothelial wound healing. This protective effect was inhibited by CSEaq in a dose-dependent manner through the AKT/eNOS pathway. Low as well as high laminar flow decreased adhesion of monocytes to endothelial cells. Whereas, monocyte adhesion was increased by CSEaq under low laminar flow, this was not evident under high laminar flow.This study shows the activation of major atherosclerotic key parameters by CSEaq. Within this process, high laminar flow is likely to reduce the harmful effects of CSEaq to a certain degree. The

  13. Coregulation of glucose uptake and vascular endothelial growth factor (VEGF) in two small-cell lung cancer (SCLC) sublines in vivo and in vitro

    DEFF Research Database (Denmark)

    Pedersen, M W; Holm, S; Lund, E L

    2001-01-01

    We examined the relationship between (18)F- labeled 2-fluro-2-deoxy-d-glucose (FDG) uptake, and expression of glucose transporters (GLUTs) in two human small-cell lung cancer (SCLC) lines CPH 54A and CPH 54B. Changes in the expression of GLUTs and vascular endothelial growth factor (VEGF) during 12......-, 18-, and 24 hours of severe hypoxia in vivo (xenografts) and in vitro (cell cultures) were recorded for both tumor lines. The two SCLC lines are subpopulations of the same patient tumor. In spite of their common genomic origin they represent consistently different metabolic and microenvironmental...... phenotypes as well as treatment sensitivities. There were higher levels of Glut-1 protein in 54B and a correspondingly higher FDG uptake in this tumor line (P

  14. Human endothelial progenitor cells rescue cortical neurons from oxygen-glucose deprivation induced death.

    Science.gov (United States)

    Bacigaluppi, Susanna; Donzelli, Elisabetta; De Cristofaro, Valentina; Bragazzi, Nicola Luigi; D'Amico, Giovanna; Scuteri, Arianna; Tredici, Giovanni

    2016-09-19

    Cerebral ischemia is characterized by both acute and delayed neuronal injuries. Neuro-protection is a major issue that should be properly addressed from a pharmacological point of view, and cell-based treatment approaches are of interest due to their potential pleiotropic effects. Endothelial progenitor cells have the advantage of being mobilized from the bone marrow into the circulation, but have been less studied than other stem cells, such as mesenchymal stem cells. Therefore, the comparison between human endothelial progenitor cells (hEPC) and human mesenchymal progenitor cells (hMSC) in terms of efficacy in rescuing neurons from cell death after transitory ischemia is the aim of the current study, in the effort to address further directions. In vitro model of oxygen-glucose deprivation (OGD) on a primary culture of rodent cortical neurons was set up with different durations of exposure: 1, 2 and 3hrs with assessment of neuron survival. The 2hrs OGD was chosen for the subsequent experiments. After 2hrs OGD neurons were either placed in indirect co-culture with hMSC or hEPC or cultured in hMSC or hEPC conditioned medium and cell viability was evaluated by MTT assay. At day 2 after 2hrs OGD exposure, mean neuronal survival was 47.9±24.2%. In contrast, after treatment with hEPC and hMSC indirect co-culture was 74.1±27.3%; and 69.4±18.8%, respectively. In contrast, treatment with conditioned medium did not provide any advantage in terms of survival to OGD neurons The study shows the efficacy of hEPC in indirect co-culture to rescue neurons from cell death after OGD, comparable to that of hMSC. hEPC deserve further studies given their potential interest for ischemia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Hyperglycemia (High Blood Glucose)

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  16. Hydrogen sulfide inhibits high glucose-induced NADPH oxidase 4 expression and matrix increase by recruiting inducible nitric oxide synthase in kidney proximal tubular epithelial cells.

    Science.gov (United States)

    Lee, Hak Joo; Lee, Doug Yoon; Mariappan, Meenalakshmi M; Feliers, Denis; Ghosh-Choudhury, Goutam; Abboud, Hanna E; Gorin, Yves; Kasinath, Balakuntalam S

    2017-04-07

    High-glucose increases NADPH oxidase 4 (NOX4) expression, reactive oxygen species generation, and matrix protein synthesis by inhibiting AMP-activated protein kinase (AMPK) in renal cells. Because hydrogen sulfide (H 2 S) inhibits high glucose-induced matrix protein increase by activating AMPK in renal cells, we examined whether H 2 S inhibits high glucose-induced expression of NOX4 and matrix protein and whether H 2 S and NO pathways are integrated. High glucose increased NOX4 expression and activity at 24 h in renal proximal tubular epithelial cells, which was inhibited by sodium hydrosulfide (NaHS), a source of H 2 S. High glucose decreased AMPK phosphorylation and activity, which was restored by NaHS. Compound C, an AMPK inhibitor, prevented NaHS inhibition of high glucose-induced NOX4 expression. NaHS inhibition of high glucose-induced NOX4 expression was abrogated by N (ω)-nitro-l-arginine methyl ester, an inhibitor of NOS. NaHS unexpectedly augmented the expression of inducible NOS (iNOS) but not endothelial NOS. iNOS siRNA and 1400W, a selective iNOS inhibitor, abolished the ameliorative effects of NaHS on high glucose-induced NOX4 expression, reactive oxygen species generation, and, matrix laminin expression. Thus, H 2 S recruits iNOS to generate NO to inhibit high glucose-induced NOX4 expression, oxidative stress, and matrix protein accumulation in renal epithelial cells; the two gasotransmitters H 2 S and NO and their interaction may serve as therapeutic targets in diabetic kidney disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Hyperglycemia (High Blood Glucose)

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  18. Clinical value of Flash glucose monitoring in patients with type 1 diabetes treated with continuous subcutaneous insulin infusion.

    Science.gov (United States)

    Moreno-Fernandez, Jesus; Pazos-Couselo, Marcos; González-Rodriguez, Maria; Rozas, Pedro; Delgado, Manuel; Aguirre, Miguel; Garcia-Lopez, Jose Manuel

    2018-06-12

    To analyze the clinical impact of the Flash glucose monitoring system in patients with type 1 diabetes mellitus (T1DM) treated with continuous subcutaneous insulin infusion (CSII). A 24-week retrospective cohort study in CSII-treated T1DM patients exposed (1:1) to the Flash glucose monitoring system vs. self-monitoring of capillary blood glucose (SMBG). The primary outcome was the difference in hemoglobin A1c (HbA1c) levels between both groups at the end of the study. Thirty-six patients with a mean age of 38.2 years (range 22-55) and a mean T1DM duration of 20.9±7.8 years, treated with CSII for 7.1±5.4 years, were enrolled into the study. At the end of the study, mean HbA1c levels improved in patients in the Flash group (7.1±0.7 vs. 7.8±1.0, p=0.04). Only the Flash group showed a significant decrease in HbA1c levels of -0.4% (95% CI, -0.6, -0.2; p=0.004) during follow-up. Flash patients captured 93.9% of data through 17.8±9.9 scans daily. In fact, the Flash cohort showed a three-fold increase in daily self-monitoring of glucose, while daily frequency of SMBG decreased during the study (-1.8 tests/24h (95% CI -3, -0.7; p=0.01). No safety issues related to Flash use were recorded. The Flash glucose monitoring system is a novel approach to improve blood glucose control in CSII-treated T1DM patients. Randomized controlled trials are needed to assess the effectiveness of this system in CSII-treated T1DM patients. Copyright © 2018 SEEN y SED. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Antiangiogenic activity of 2-deoxy-D-glucose.

    Directory of Open Access Journals (Sweden)

    Jaime R Merchan

    2010-10-01

    Full Text Available During tumor angiogenesis, endothelial cells (ECs are engaged in a number of energy consuming biological processes, such as proliferation, migration, and capillary formation. Since glucose uptake and metabolism are increased to meet this energy need, the effects of the glycolytic inhibitor 2-deoxy-D-glucose (2-DG on in vitro and in vivo angiogenesis were investigated.In cell culture, 2-DG inhibited EC growth, induced cytotoxicity, blocked migration, and inhibited actively forming but not established endothelial capillaries. Surprisingly, 2-DG was a better inhibitor of these EC properties than two more efficacious glycolytic inhibitors, 2-fluorodeoxy-D-glucose and oxamate. As an alternative to a glycolytic inhibitory mechanism, we considered 2-DG's ability to interfere with endothelial N-linked glycosylation. 2-DG's effects were reversed by mannose, an N-linked glycosylation precursor, and at relevant concentrations 2-DG also inhibited synthesis of the lipid linked oligosaccharide (LLO N-glycosylation donor in a mannose-reversible manner. Inhibition of LLO synthesis activated the unfolded protein response (UPR, which resulted in induction of GADD153/CHOP and EC apoptosis (TUNEL assay. Thus, 2-DG's effects on ECs appeared primarily due to inhibition of LLOs synthesis, not glycolysis. 2-DG was then evaluated in two mouse models, inhibiting angiogenesis in both the matrigel plug assay and the LH(BETAT(AG transgenic retinoblastoma model.In conclusion, 2-DG inhibits endothelial cell angiogenesis in vitro and in vivo, at concentrations below those affecting tumor cells directly, most likely by interfering with N-linked glycosylation rather than glycolysis. Our data underscore the importance of glucose metabolism on neovascularization, and demonstrate a novel approach for anti-angiogenic strategies.

  20. NOX2-Induced Activation of Arginase and Diabetes-Induced Retinal Endothelial Cell Senescence

    Directory of Open Access Journals (Sweden)

    Modesto Rojas

    2017-06-01

    Full Text Available Increases in reactive oxygen species (ROS and decreases in nitric oxide (NO have been linked to vascular dysfunction during diabetic retinopathy (DR. Diabetes can reduce NO by increasing ROS and by increasing activity of arginase, which competes with nitric oxide synthase (NOS for their commons substrate l-arginine. Increased ROS and decreased NO can cause premature endothelial cell (EC senescence leading to defective vascular repair. We have previously demonstrated the involvement of NADPH oxidase 2 (NOX2-derived ROS, decreased NO and overactive arginase in DR. Here, we investigated their impact on diabetes-induced EC senescence. Studies using diabetic mice and retinal ECs treated with high glucose or H2O2 showed that increases in ROS formation, elevated arginase expression and activity, and decreased NO formation led to premature EC senescence. NOX2 blockade or arginase inhibition prevented these effects. EC senescence was also increased by inhibition of NOS activity and this was prevented by treatment with a NO donor. These results indicate that diabetes/high glucose-induced activation of arginase and decreases in NO bioavailability accelerate EC senescence. NOX2-generated ROS contribute importantly to this process. Blockade of NOX2 or arginase represents a strategy to prevent diabetes-induced premature EC senescence by preserving NO bioavailability.

  1. Quinapril treatment increases insulin-stimulated endothelial function and adiponectin gene expression in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Hermann, Thomas S; Li, Weijie; Dominguez, Helena

    2005-01-01

    OBJECTIVE: Angiotensin-converting enzyme inhibitors reduce cardiovascular mortality and improve endothelial function in type 2 diabetic patients. We hypothesized that 2 months of quinapril treatment would improve insulin-stimulated endothelial function and glucose uptake in type 2 diabetic subjects...... and simultaneously increase the expression of genes that are pertinent for endothelial function and metabolism. METHODS: Twenty-four type 2 diabetic subjects were randomized to receive 2 months of quinapril 20 mg daily or no treatment in an open parallel study. Endothelium-dependent and -independent vasodilation...... occlusion plethysmography. Gene expression was measured by real-time PCR. RESULTS: Quinapril treatment increased insulin-stimulated endothelial function in the type 2 diabetic subjects (P = 0.005), whereas forearm glucose uptake was unchanged. Endothelial function was also increased by quinapril (P = 0...

  2. Blood-Brain Glucose Transfer: Repression in Chronic Hyperglycemia

    Science.gov (United States)

    Gjedde, Albert; Crone, Christian

    1981-10-01

    Diabetic patients with increased plasma glucose concentrations may develop cerebral symptoms of hypoglycemia when their plasma glucose is rapidly lowered to normal concentrations. The symptoms may indicate insufficient transport of glucose from blood to brain. In rats with chronic hyperglycemia the maximum glucose transport capacity of the blood-brain barrier decreased from 400 to 290 micromoles per 100 grams per minute. When plasma glucose was lowered to normal values, the glucose transport rate into brain was 20 percent below normal. This suggests that repressive changes of the glucose transport mechanism occur in brain endothelial cells in response to increased plasma glucose.

  3. Mechanisms of Diabetes-Induced Endothelial Cell Senescence: Role of Arginase 1

    Directory of Open Access Journals (Sweden)

    Esraa Shosha

    2018-04-01

    Full Text Available We have recently found that diabetes-induced premature senescence of retinal endothelial cells is accompanied by NOX2-NADPH oxidase-induced increases in the ureohydrolase enzyme arginase 1 (A1. Here, we used genetic strategies to determine the specific involvement of A1 in diabetes-induced endothelial cell senescence. We used A1 knockout mice and wild type mice that were rendered diabetic with streptozotocin and retinal endothelial cells (ECs exposed to high glucose or transduced with adenovirus to overexpress A1 for these experiments. ABH [2(S-Amino-6-boronohexanoic acid] was used to inhibit arginase activity. We used Western blotting, immunolabeling, quantitative PCR, and senescence associated β-galactosidase (SA β-Gal activity to evaluate senescence. Analyses of retinal tissue extracts from diabetic mice showed significant increases in mRNA expression of the senescence-related proteins p16INK4a, p21, and p53 when compared with non-diabetic mice. SA β-Gal activity and p16INK4a immunoreactivity were also increased in retinal vessels from diabetic mice. A1 gene deletion or pharmacological inhibition protected against the induction of premature senescence. A1 overexpression or high glucose treatment increased SA β-Gal activity in cultured ECs. These results demonstrate that A1 is critically involved in diabetes-induced senescence of retinal ECs. Inhibition of arginase activity may therefore be an effective therapeutic strategy to alleviate diabetic retinopathy by preventing premature senescence.

  4. A Novel Peptide to Treat Oral Mucositis Blocks Endothelial and Epithelial Cell Apoptosis

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    Wu Xiaoyan; Chen Peili [Department of Medicine, University of Chicago, Chicago, Illinois (United States); Sonis, Stephen T. [Division of Oral Medicine, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Biomodels, Watertown, Massachusetts (United States); Lingen, Mark W. [Department of Pathology, University of Chicago, Chicago, Illinois (United States); Berger, Ann [NephRx Corporation, Kalamazoo, Michigan (United States); Toback, F. Gary, E-mail: gtoback@medicine.bsd.uchicago.edu [Department of Medicine, University of Chicago, Chicago, Illinois (United States)

    2012-07-01

    Purpose: No effective agents currently exist to treat oral mucositis (OM) in patients receiving chemoradiation for the treatment of head-and-neck cancer. We identified a novel 21-amino acid peptide derived from antrum mucosal protein-18 that is cytoprotective, mitogenic, and motogenic in tissue culture and animal models of gastrointestinal epithelial cell injury. We examined whether administration of antrum mucosal protein peptide (AMP-p) could protect against and/or speed recovery from OM. Methods and Materials: OM was induced in established hamster models by a single dose of radiation, fractionated radiation, or fractionated radiation together with cisplatin to simulate conventional treatments of head-and-neck cancer. Results: Daily subcutaneous administration of AMP-p reduced the occurrence of ulceration and accelerated mucosal recovery in all three models. A delay in the onset of erythema after irradiation was observed, suggesting that a protective effect exists even before injury to mucosal epithelial cells occurs. To test this hypothesis, the effects of AMP-p on tumor necrosis factor-{alpha}-induced apoptosis were studied in an endothelial cell line (human dermal microvascular endothelial cells) as well as an epithelial cell line (human adult low-calcium, high-temperature keratinocytes; HaCaT) used to model the oral mucosa. AMP-p treatment, either before or after cell monolayers were exposed to tumor necrosis factor-{alpha}, protected against development of apoptosis in both cell types when assessed by annexin V and propidium iodide staining followed by flow cytometry or ligase-mediated polymerase chain reaction. Conclusions: These observations suggest that the ability of AMP-p to attenuate radiation-induced OM could be attributable, at least in part, to its antiapoptotic activity.

  5. Hyperglycemia (High Blood Glucose)

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  6. Hyperglycemia (High Blood Glucose)

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  7. Hyperglycemia (High Blood Glucose)

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  8. Hyperglycemia (High Blood Glucose)

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  9. Hyperglycemia (High Blood Glucose)

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  10. Arginase promotes skeletal muscle arteriolar endothelial dysfunction in diabetic rats.

    Directory of Open Access Journals (Sweden)

    Fruzsina K. Johnson

    2013-05-01

    Full Text Available Endothelial dysfunction is a characteristic feature in diabetes that contributes to the development of vascular disease. Recently, arginase has been implicated in triggering endothelial dysfunction in diabetic patients and animals by competing with endothelial nitric oxide synthase for substrate L-arginine. While most studies have focused on the coronary circulation and large conduit blood vessels, the role of arginase in mediating diabetic endothelial dysfunction in other vascular beds has not been fully investigated. In the present study, we determined whether arginase contributes to endothelial dysfunction in skeletal muscle arterioles of diabetic rats. Diabetes was induced in male Sprague Dawley rats by streptozotocin injection. Four weeks after streptozotocin administration, blood glucose, glycated hemoglobin, and vascular arginase activity were significantly increased. In addition, a significant increase in arginase I and II mRNA expression was detected in gracilis muscle arterioles of diabetic rats compared to age-matched, vehicle control animals. To examine endothelial function, first-order gracilis muscle arterioles were isolated, cannulated in a pressure myograph system, exposed to graded levels of luminal flow, and internal vessel diameter measured. Increases in luminal flow (0-50µL/min caused progressive vasodilation in arterioles isolated from control, normoglycemic animals. However, flow-induced vasodilation was absent in arterioles obtained from streptozotocin-treated rats. Acute in-vitro pretreatment of blood vessels with the arginase inhibitors Nω-hydroxy-nor-L-arginine or S-(2-boronoethyl-L-cysteine restored flow-induced responses in arterioles from diabetic rats and abolished differences between diabetic and control animals. Similarly, acute in-vitro pretreatment with L-arginine returned flow-mediated vasodilation in vessels from diabetic animals to that of control rats. In contrast, D-arginine failed to restore flow

  11. Hyperglycemia adversely modulates endothelial nitric oxide synthase during anesthetic preconditioning through tetrahydrobiopterin- and heat shock protein 90-mediated mechanisms.

    Science.gov (United States)

    Amour, Julien; Brzezinska, Anna K; Jager, Zachary; Sullivan, Corbin; Weihrauch, Dorothee; Du, Jianhai; Vladic, Nikolina; Shi, Yang; Warltier, David C; Pratt, Phillip F; Kersten, Judy R

    2010-03-01

    Endothelial nitric oxide synthase activity is regulated by (6R-)5,6,7,8-tetrahydrobiopterin (BH4) and heat shock protein 90. The authors tested the hypothesis that hyperglycemia abolishes anesthetic preconditioning (APC) through BH4- and heat shock protein 90-dependent pathways. Myocardial infarct size was measured in rabbits in the absence or presence of APC (30 min of isoflurane), with or without hyperglycemia, and in the presence or absence of the BH4 precursor sepiapterin. Isoflurane-dependent nitric oxide production was measured (ozone chemiluminescence) in human coronary artery endothelial cells cultured in normal (5.5 mm) or high (20 mm) glucose conditions, with or without sepiapterin (10 or 100 microm). APC decreased myocardial infarct size compared with control experiments (26 +/- 6% vs. 46 +/- 3%, respectively; P < 0.05), and this action was blocked by hyperglycemia (43 +/- 4%). Sepiapterin alone had no effect on infarct size (46 +/- 3%) but restored APC during hyperglycemia (21 +/- 3%). The beneficial actions of sepiapterin to restore APC were blocked by the nitric oxide synthase inhibitor N (G)-nitro-L-arginine methyl ester (47 +/- 2%) and the BH4 synthesis inhibitor N-acetylserotonin (46 +/- 3%). Isoflurane increased nitric oxide production to 177 +/- 13% of baseline, and this action was attenuated by high glucose concentrations (125 +/- 6%). Isoflurane increased, whereas high glucose attenuated intracellular BH4/7,8-dihydrobiopterin (BH2) (high performance liquid chromatography), heat shock protein 90-endothelial nitric oxide synthase colocalization (confocal microscopy) and endothelial nitric oxide synthase activation (immunoblotting). Sepiapterin increased BH4/BH2 and dose-dependently restored nitric oxide production during hyperglycemic conditions (149 +/- 12% and 175 +/- 9%; 10 and 100 microm, respectively). The results indicate that tetrahydrobiopterin and heat shock protein 90-regulated endothelial nitric oxide synthase activity play a central

  12. Hyperglycemia (High Blood Glucose)

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  19. The Cytotoxic Role of Intermittent High Glucose on Apoptosis and Cell Viability in Pancreatic Beta Cells

    Directory of Open Access Journals (Sweden)

    Zhen Zhang

    2014-01-01

    Full Text Available Objectives. Glucose fluctuations are both strong predictor of diabetic complications and crucial factor for beta cell damages. Here we investigated the effect of intermittent high glucose (IHG on both cell apoptosis and proliferation activity in INS-1 cells and the potential mechanisms. Methods. Cells were treated with normal glucose (5.5 mmol/L, constant high glucose (CHG (25 mmol/L, and IHG (rotation per 24 h in 11.1 or 25 mmol/L for 7 days. Reactive oxygen species (ROS, xanthine oxidase (XOD level, apoptosis, cell viability, cell cycle, and expression of cyclinD1, p21, p27, and Skp2 were determined. Results. We found that IHG induced more significant apoptosis than CHG and normal glucose; intracellular ROS and XOD levels were more markedly increased in cells exposed to IHG. Cells treated with IHG showed significant decreased cell viability and increased cell proportion in G0/G1 phase. Cell cycle related proteins such as cyclinD1 and Skp2 were decreased significantly, but expressions of p27 and p21 were increased markedly. Conclusions. This study suggested that IHG plays a more toxic effect including both apoptosis-inducing and antiproliferative effects on INS-1 cells. Excessive activation of cellular stress and regulation of cyclins might be potential mechanism of impairment in INS-1 cells induced by IHG.

  20. Hypoglycemia in type 2 diabetes patients treated with insulin: the advantages of continuous glucose monitoring

    Directory of Open Access Journals (Sweden)

    Vadim Valer'evich Klimontov

    2014-03-01

    Full Text Available Aims.  To determine the incidence and risk factors for hypoglycemia in elderly insulin-treated type 2 diabetes mellitus (T2DM patients by means of continuous glucose monitoring (CGM. Materials and Methods.  We observed seventy-six hospitalized patients with T2DM, aged 65 to 79 years. Treatment with basal insulin (n=36, premixed insulin (n=12 or basal-bolus insulin regimen (n=28 was followed by metformin (n=44, glimepiride (n=14 and dipeptidyl peptidase-4 inhibitors (n=14. 2-days CGM with retrospective data analysis was performed in all patients. During CGM, three fasting and three 2-h postprandial finger-prick glucose values were obtained daily with portable glucose meter. Results.  Hypoglycemia (identified as blood glucose

  1. Influence of high glucose and advanced glycation end-products (ages) levels in human osteoblast-like cells gene expression.

    Science.gov (United States)

    Miranda, Cristina; Giner, Mercè; Montoya, M José; Vázquez, M Angeles; Miranda, M José; Pérez-Cano, Ramón

    2016-08-31

    Type 2 diabetes mellitus (T2DM) is associated with an increased risk of osteoporotic fracture. Several factors have been identified as being potentially responsible for this risk, such as alterations in bone remodelling that may have been induced by changes in circulating glucose or/and by the presence of non-oxidative end products of glycosylation (AGEs). The aim of this study is to assess whether such variations generate a change in the gene expression related to the differentiation and osteoblast activity (OPG, RANKL, RUNX2, OSTERIX, and AGE receptor) in primary cultures of human osteoblast-like cells (hOB). We recruited 32 patients; 10 patients had osteoporotic hip fractures (OP group), 12 patients had osteoporotic hip fractures with T2DM (T2DM group), and 10 patients had hip osteoarthritis (OA group) with no osteoporotic fractures and no T2DM. The gene expression was analyzed in hOB cultures treated with physiological glucose concentration (4.5 mM) as control, high glucose (25 mM), and high glucose plus AGEs (2 μg/ml) for 24 h. The hOB cultures from patients with hip fractures presented slower proliferation. Additionally, the hOB cultures from the T2DM group were the most negatively affected with respect to RUNX2 and OSX gene expression when treated solely with high glucose or with high glucose plus AGEs. Moreover, high levels of glucose induced a major decrease in the RANKL/OPG ratio when comparing the OP and the T2DM groups to the OA group. Our data indicates an altered bone remodelling rate in the T2DM group, which may, at least partially, explain the reduced bone strength and increased incidence of non-traumatic fractures in diabetic patients.

  2. High glucose increases Cdk5 activity in podocytes via transforming growth factor-β1 signaling pathway

    International Nuclear Information System (INIS)

    Zhang, Yue; Li, Hongbo; Hao, Jun; Zhou, Yi; Liu, Wei

    2014-01-01

    Podocytes are highly specialized and terminally differentiated glomerular cells that play a vital role in the development and progression of diabetic nephropathy (DN). Cyclin-dependent kinase 5 (Cdk5), who is an atypical but essential member of the Cdk family of proline-directed serine/threonine kinases, has been shown as a key regulator of podocyte differentiation, proliferation and morphology. Our previous studies demonstrated that the expression of Cdk5 was significantly increased in podocytes of diabetic rats, and was closely related with podocyte injury of DN. However, the mechanisms of how expression and activity of Cdk5 are regulated under the high glucose environment have not yet been fully elucidated. In this study, we showed that high glucose up-regulated the expression of Cdk5 and its co-activator p35 with a concomitant increase in Cdk5 kinase activity in conditionally immortalized mouse podocytes in vitro. When exposed to 30 mM glucose, transforming growth factor-β1 (TGF-β1) was activated. Most importantly, we found that SB431542, the Tgfbr1 inhibitor, significantly decreased the expression of Cdk5 and p35 and Cdk5 kinase activity in high glucose-treated podocytes. Moreover, high glucose increased the expression of early growth response-1 (Egr-1) via TGF-β1-ERK1/2 pathway in podocytes and inhibition of Egr-1 by siRNA decreased p35 expression and Cdk5 kinase activity. Furthermore, inhibition of Cdk5 kinase activity effectively alleviated podocyte apoptosis induced by high glucose or TGF-β1. Thus, the TGF-β1-ERK1/2-Egr-1 signaling pathway may regulate the p35 expression and Cdk5 kinase activity in high glucose-treated podocytes, which contributes to podocyte injury of DN. - Highlights: • HG up-regulated the expression of Cdk5 and p35, and Cdk5 activity in podocytes. • HG activated TGF-β1 pathway and SB431542 inhibited Cdk5 expression and activity. • HG increased the expression of Egr-1 via TGF-β1-ERK1/2 pathway. • Inhibition of Egr-1

  3. Red meat intake, insulin resistance, and markers of endothelial function among Iranian women.

    Science.gov (United States)

    Barak, Farzaneh; Falahi, Ebrahim; Keshteli, Ammar Hassanzadeh; Yazdannik, Ahmadreza; Saneei, Parvane; Esmaillzadeh, Ahmad

    2015-02-01

    Few data, with conflicting findings, are available linking red meat consumption to indicators of insulin resistance and endothelial dysfunction. This study aimed to investigate the association of red meat consumption with insulin resistance and endothelial dysfunction among a sample of female nurses in Isfahan, Iran. This cross-sectional study was carried out among 420 female nurses who were selected by a multistage cluster random sampling method. Usual dietary intakes were assessed using a validated food frequency questionnaire. Red meat intake was calculated by summing up the consumption of all kinds of red meat in foods and processed meat in sausages and fast foods. To measure serum concentrations of adhesion molecules and glycemic indexes, a fasting blood sample was taken. After adjustment for potential confounders, high red meat intake was significantly associated with higher fasting plasma glucose, homeostasis model assessment of insulin resistance, and lower quantitative insulin sensitivity check index. Although high red meat intake was significantly associated with higher serum insulin levels and lower homeostasis model assessment of beta-cell function in the crude model, after controlling for BMI, the association was no longer significant. Red meat consumption was associated with high concentrations of E-selectin, soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble intercellular adhesion molecule-1 (sICAM-1) after adjustment for different potential confounders. We found that increased red meat intake was associated with high concentrations of plasma endothelial dysfunction biomarkers and abnormal glucose homeostasis among Iranian women. Prospective studies are required to confirm these findings. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. New therapeutic modality for corneal endothelial disease using Rho-associated kinase inhibitor eye drops.

    Science.gov (United States)

    Koizumi, Noriko; Okumura, Naoki; Ueno, Morio; Kinoshita, Shigeru

    2014-11-01

    Corneal endothelial dysfunction accompanied by visual disturbance is a primary indication for corneal endothelial transplantation. However, despite the value and potential of endothelial graft surgery, a strictly pharmacological approach for treating corneal endothelial dysfunction remains an attractive proposition. Previously, we reported that the selective Rho-associated kinase (ROCK) inhibitor Y-27632 promotes cell adhesion and proliferation, and inhibits the apoptosis of primate corneal endothelial cells in culture. These findings have led us to develop a novel medical treatment for the early phase of corneal endothelial disease using ROCK inhibitor eye drops. In rabbit and monkey models of partial endothelial dysfunction, we showed that corneal endothelial wound healing was accelerated via the topical application of ROCK inhibitor to the ocular surface, resulting in the regeneration of a corneal endothelial monolayer with a high endothelial cell density. Based on these animal studies, we are now attempting to advance the clinical application of ROCK inhibitor eye drops for patients with corneal endothelial dysfunction. A pilot clinical study was performed at the Kyoto Prefectural University of Medicine, and the effects of Y-27632 eye drops after transcorneal freezing were evaluated in 8 patients with corneal endothelial dysfunction. We observed a positive effect of ROCK inhibitor eye drops in treating patients with central edema caused by Fuchs corneal endothelial dystrophy. We believe that our new findings will contribute to the establishment of a new approach for the treatment of corneal endothelial dysfunction.

  5. Molecular action mechanism against apoptosis by aqueous extract from guava budding leaves elucidated with human umbilical vein endothelial cell (HUVEC) model.

    Science.gov (United States)

    Hsieh, Chiu-Lan; Huang, Chien-Ning; Lin, Yuh-Charn; Peng, Robert Y

    2007-10-17

    Chronic cardiovascular and neurodegenerative complications induced by hyperglycemia have been considered to be associated most relevantly with endothelial cell damages (ECD). The protective effects of the aqueous extract of Psidium guajava L. budding leaves (PE) on the ECD in human umbilical vein endothelial cell (HUVEC) model were investigated. Results revealed that glyoxal (GO) and methylglyoxal (MGO) resulting from the glycative and autoxidative reactions of the high blood sugar glucose (G) evoked a huge production of ROS and NO, which in turn increased the production of peroxynitrite, combined with the activation of the nuclear factor kappaB (NFkappaB), leading to cell apoptosis. High plasma glucose activated p38-MAPK, and high GO increased the expressions of p38-MAPK and JNK-MAPK, whereas high MGO levels induced the activity of ERK-MAPK. Glucose and dicarbonyl compounds were all found to be good inducers of intracellular PKCs, which together with MAPK acted as the upstream triggering factor to activate NFkappaB. Conclusively, high plasma glucose together with dicarbonyl compounds can trigger the signaling pathways of MAPK and PKC and induce cell apoptosis through ROS and peroxynitrite stimulation and finally by NFkappaB activation. Such effects of PE were ascribed to its high plant polyphenolic (PPP) contents, the latter being potent ROS inhibitors capable of blocking the glycation of proteins, which otherwise could have brought forth severe detrimental effects to the cells.

  6. The role of shear stress in Blood-Brain Barrier endothelial physiology

    Directory of Open Access Journals (Sweden)

    Puvenna Vikram

    2011-05-01

    Full Text Available Abstract Background One of the most important and often neglected physiological stimuli contributing to the differentiation of vascular endothelial cells (ECs into a blood-brain barrier (BBB phenotype is shear stress (SS. With the use of a well established humanized dynamic in vitro BBB model and cDNA microarrays, we have profiled the effect of SS in the induction/suppression of ECs genes and related functions. Results Specifically, we found a significant upregulation of tight and adherens junctions proteins and genes. Trans-endothelial electrical resistance (TEER and permeability measurements to know substances have shown that SS promoted the formation of a tight and highly selective BBB. SS also increased the RNA level of multidrug resistance transporters, ion channels, and several p450 enzymes. The RNA level of a number of specialized carrier-mediated transport systems (e.g., glucose, monocarboxylic acid, etc. was also upregulated. RNA levels of modulatory enzymes of the glycolytic pathway (e.g., lactate dehydrogenase were downregulated by SS while those involved in the Krebs cycle (e.g., lactate and other dehydrogenases were upregulated. Measurements of glucose consumption versus lactate production showed that SS negatively modulated the glycolytic bioenergetic pathways of glucose metabolism in favor of the more efficient aerobic respiration. BBB ECs are responsive to inflammatory stimuli. Our data showed that SS increased the RNA levels of integrins and vascular adhesion molecules. SS also inhibited endothelial cell cycle via regulation of BTG family proteins encoding genes. This was paralleled by significant increase in the cytoskeletal protein content while that of membrane, cytosol, and nuclear sub-cellular fractions decreased. Furthermore, analysis of 2D gel electrophoresis (which allows identifying a large number of proteins per sample of EC proteins extracted from membrane sub-cellular endothelial fractions showed that SS increased

  7. Hyperglycemia (High Blood Glucose)

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  8. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools ... Complications DKA (Ketoacidosis) & Ketones Kidney Disease ... than planned or exercised less than planned. You have stress from an illness, such as a cold or flu. You have ...

  9. Thiamine and benfotiamine prevent apoptosis induced by high glucose-conditioned extracellular matrix in human retinal pericytes.

    Science.gov (United States)

    Beltramo, Elena; Nizheradze, Konstantin; Berrone, Elena; Tarallo, Sonia; Porta, Massimo

    2009-10-01

    Early and selective loss of pericytes and thickening of the basement membrane are hallmarks of diabetic retinopathy. We reported reduced adhesion, but no changes in apoptosis, of bovine retinal pericytes cultured on extracellular matrix (ECM) produced by endothelial cells in high glucose (HG). Since human and bovine pericytes may behave differently in conditions mimicking the diabetic milieu, we verified the behaviour of human retinal pericytes cultured on HG-conditioned ECM. Pericytes were cultured in physiological/HG on ECM produced by human umbilical vein endothelial cells in physiological/HG, alone or in the presence of thiamine and benfotiamine. Adhesion, proliferation, apoptosis, p53 and Bcl-2/Bax ratio (mRNA levels and protein concentrations) were measured in wild-type and immortalized human pericytes. Both types of pericytes adhered less to HG-conditioned ECM and plastic than to physiological glucose-conditioned ECM. DNA synthesis was impaired in pericytes cultured in HG on the three different surfaces but there were no differences in proliferation. DNA fragmentation and Bcl-2/Bax ratio were greatly enhanced by HG-conditioned ECM in pericytes kept in both physiological and HG. Addition of thiamine and benfotiamine to HG during ECM production completely prevented these damaging effects. Apoptosis is strongly increased in pericytes cultured on ECM produced by endothelium in HG, probably due to impairment of the Bcl-2/Bax ratio. Thiamine and benfotiamine completely revert this effect. This behaviour is therefore completely different from that of bovine pericytes, underlining the importance of establishing species-specific cell models to study the mechanisms of diabetic retinopathy. (c) 2009 John Wiley & Sons, Ltd.

  10. Endothelial microparticles released by activated protein C protect beta cells through EPCR/PAR1 and annexin A1/FPR2 pathways in islets.

    Science.gov (United States)

    Kreutter, Guillaume; Kassem, Mohamad; El Habhab, Ali; Baltzinger, Philippe; Abbas, Malak; Boisrame-Helms, Julie; Amoura, Lamia; Peluso, Jean; Yver, Blandine; Fatiha, Zobairi; Ubeaud-Sequier, Geneviève; Kessler, Laurence; Toti, Florence

    2017-11-01

    Islet transplantation is associated with early ischaemia/reperfusion, localized coagulation and redox-sensitive endothelial dysfunction. In animal models, islet cytoprotection by activated protein C (aPC) restores islet vascularization and protects graft function, suggesting that aPC triggers various lineages. aPC also prompts the release of endothelial MP that bear EPCR, its specific receptor. Microparticles (MP) are plasma membrane procoagulant vesicles, surrogate markers of stress and cellular effectors. We measured the cytoprotective effects of aPC on endothelial and insulin-secreting Rin-m5f β-cells and its role in autocrine and paracrine MP-mediated cell crosstalk under conditions of oxidative stress. MP from aPC-treated primary endothelial (EC) or β-cells were applied to H 2 O 2 -treated Rin-m5f. aPC activity was measured by enzymatic assay and ROS species by dihydroethidium. The capture of PKH26-stained MP and the expression of EPCR were probed by fluorescence microscopy and apoptosis by flow cytometry. aPC treatment enhanced both annexin A1 (ANXA1) and PAR-1 expression in EC and to a lesser extent in β-cells. MP from aPC-treated EC (eM aPC ) exhibited high EPCR and annexin A1 content, protected β-cells, restored insulin secretion and were captured by 80% of β cells in a phosphatidylserine and ANXA1-dependent mechanism. eMP activated EPCR/PAR-1 and ANXA1/FPR2-dependent pathways and up-regulated the expression of EPCR, and of FPR2/ALX, the ANXA1 receptor. Cytoprotection was confirmed in H 2 O 2 -treated rat islets with increased viability (62% versus 48% H 2 O 2 ), reduced apoptosis and preserved insulin secretion in response to glucose elevation (16 versus 5 ng/ml insulin per 10 islets). MP may prove a promising therapeutic tool in the protection of transplanted islets. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  11. Corneal endothelial rejection after penetrating keratoplasty treated with intravenous and topic corticosteroid: one year follow up

    Directory of Open Access Journals (Sweden)

    Ricardo Yuji Abe

    2013-02-01

    Full Text Available OBJECTIVE: To analyze the recovery of visual acuity (VA and graft survival after first episode of endothelial rejection in penetrating keratoplasty (PKP treated with intravenous (IV and topic corticosteroid. METHODS: Interventional, prospective, non-comparative case series study evolving 32 PKP patients in one year follow up, who presented first episode of corneal endothelial rejection. The patients were submitted to 500 mg IV injection of methylprednisolone in association with topical prednisolone. Main outcome measures included VA recovery and corneal edema regression. Second outcome included new rejections and graft failure. Multivariate analysis techniques were used to estimate rates of graft outcome events and the impact of risk factors. RESULTS: A total of 32 eyes from 32 patients (13 male and 19 female were included in the study. The mean VA (in number of letters before rejection was 48 (22 to 88 letters. Patients treated within 7 days or less of initial symptoms had better VA recovery, corneal edema regression and less graft failure (p<0.001. Patients with previous ocular surgery had worse VA recovery and more graft failure (p<0.047. CONCLUSION: The association between the other risk factors and the outcomes did not reach statistical significance in the multivariate model because of the small numbers of patients. Methylprednisolone in association with topical prednisolone is an alternative treatment for graft rejection. Our study showed that patients treated within 7 days of symptoms and no previous anterior segment surgery had better visual outcome and graft survival after treatment.

  12. Effects of acute and chronic attenuation of postprandial hyperglycemia on postglucose-load endothelial function in insulin resistant individuals: is stimulation of first phase insulin secretion beneficial for the endothelial function?

    DEFF Research Database (Denmark)

    Major-Pedersen, A; Ihlemann, N; Hermann, T S

    2008-01-01

    The aim of the study is to determine if attenuation of postprandial hyperglycemia, by acutely and chronically enhancing postprandial insulin secretion in insulin-resistant individuals, improves the endothelial dysfunction. We assessed postoral glucose-load endothelial function in 56 insulin....... We found no relationship between postprandial hyperglycemia and post-OGL FMD....

  13. Laminar shear stress inhibits endothelial cell metabolism via KLF2-mediated repression of PFKFB3

    NARCIS (Netherlands)

    Doddaballapur, Anuradha; Michalik, Katharina M.; Manavski, Yosif; Lucas, Tina; Houtkooper, Riekelt H.; You, Xintian; Chen, Wei; Zeiher, Andreas M.; Potente, Michael; Dimmeler, Stefanie; Boon, Reinier A.

    2015-01-01

    Cellular metabolism was recently shown to regulate endothelial cell phenotype profoundly. Whether the atheroprotective biomechanical stimulus elicited by laminar shear stress modulates endothelial cell metabolism is not known. Here, we show that laminar flow exposure reduced glucose uptake and

  14. Endothelial function in highly endurance-trained and sedentary, healthy young women.

    Science.gov (United States)

    Moe, Ingvild T; Hoven, Heidi; Hetland, Eva V; Rognmo, Oivind; Slørdahl, Stig A

    2005-05-01

    Endothelial function is reduced by age, chronic heart failure, coronary artery disease, hypertension or type 2 diabetes, and it is shown that aerobic exercise may reverse this trend. The effect of a high aerobic training status on endothelial function in young, healthy subjects is however less clear. The present study was designed to determine whether endothelial function is improved in highly endurance-trained young women compared to sedentary, healthy controls. Brachial artery diameter was measured in 16 endurance-trained (age: 23.7 +/- 2.5 years, maximal oxygen uptake (VO2max): 60.6 +/- 4.5 ml/kg per min) and 14 sedentary females (age: 23.7 +/- 2.1 years, VO2max: 40.5 +/- 5.6 ml/kg per min) at rest, during flow-mediated dilation (FMD) and after sublingual glycerol trinitrate administration, using high-resolution ultrasound. FMD did not differ between the endurance-trained and the sedentary females (14.8% vs 16.4%, p = NS), despite a substantial difference in VO2max of 50% (p endurance-trained group possessed however, a 9% larger resting brachial artery diameter when adjusted for body surface area. The results of the present study suggest that endothelial function is well preserved in young, healthy women, and that a high aerobic training status due to long term aerobic training does not improve the dilating capacity any further.

  15. Benfotiamine increases glucose oxidation and downregulates NADPH oxidase 4 expression in cultured human myotubes exposed to both normal and high glucose concentrations

    OpenAIRE

    Fraser, D. A.; Hessvik, N. P.; Nikolić, N.; Aas, V.; Hanssen, K. F.; Bøhn, S. K.; Thoresen, G. H.; Rustan, A. C.

    2011-01-01

    The aim of the present work was to study the effects of benfotiamine (S-benzoylthiamine O-monophosphate) on glucose and lipid metabolism and gene expression in differentiated human skeletal muscle cells (myotubes) incubated for 4 days under normal (5.5 mM glucose) and hyperglycemic (20 mM glucose) conditions. Myotubes established from lean, healthy volunteers were treated with benfotiamine for 4 days. Glucose and lipid metabolism were studied with labeled precursors. Gene expression was measu...

  16. Local cerebral metabolic rate of glucose (lCMRGlc) in treated and untreated patients with Parkinson's disease

    International Nuclear Information System (INIS)

    Rougemont, D.; Baron, J.C.; Collard, P.; Bustany, P.; Comar, D.; Agid, Y.

    1983-06-01

    Local cerebral metabolic rate of glucose (lCMRGlc) was measured twice, using positron emission tomography and 18 F-Fluoro-2-deoxy-D-glucose ( 18 FDG), in 4 patients with Parkinson disease, first unmedicated and then treated with L-DOPA. Despite a dramatic clinical improvement, no significant changes in lCMRGlc could be detected. Moreover, no reproducible differences of lCMRGlc were found between patients with Parkinson disease and with normal brain

  17. Glucose-induced serum- and glucocorticoid-regulated kinase activation in oncofetal fibronectin expression

    International Nuclear Information System (INIS)

    Khan, Zia A.; Barbin, Yousef P.; Farhangkhoee, Hana; Beier, Norbert; Scholz, Wolfgang; Chakrabarti, Subrata

    2005-01-01

    Preferential expression of oncofetal extra domain-B fibronectin (EDB + FN), a proposed angiogenic marker, has been shown in proliferative diabetic retinopathy. High levels of glucose also increase EDB + FN expression in endothelial cells (ECs) via transforming growth factor-β1 (TGF-β1) and endothelin-1 (ET-1). The present study was aimed at elucidating the role of serum- and glucocorticoid-regulated kinase (SGK-1) in glucose-induced EDB + FN expression. Using human macro- and microvascular ECs, we show that high levels of glucose, TGF-β1, and ET-1 increase the EDB + FN expression via SGK-1 alteration at the mRNA, protein, and activity levels. Inhibition of TGF-β1 and ET-1 prevented glucose-induced SGK-1 activation and the EDB + FN expression. Furthermore, using siRNA-mediated SGK-1 gene silencing, we show that glucose-induced EDB + FN expression can be completely prevented. These findings provide first evidence of glucose-induced SGK-1 activation in altered EDB + FN expression and provide novel avenues for therapeutic modalities

  18. Chronic aerobic exercise associated to dietary modification improve endothelial function and eNOS expression in high fat fed hamsters.

    Directory of Open Access Journals (Sweden)

    Beatriz C S Boa

    Full Text Available Obesity is epidemic in the western world and central adipose tissue deposition points to increased cardiovascular morbidity and mortality, independently of any association between obesity and other cardiovascular risk factors. Physical exercise has been used as non-pharmacological treatment to significantly reverse/attenuate obesity comorbidities. In this study we have investigated effects of exercise and/or dietary modification on microcirculatory function, body composition, serum glucose, iNOS and eNOS expression on 120 male hamsters treated for 12 weeks with high fat chow (HF, n = 30 starting on the 21st day of birth. From week 12 to 20, animals were randomly separated in HF (no treatment change, return to standard chow (HFSC, n = 30, high fat chow associated to an aerobic exercise training program (AET (HFEX, n = 30 and return to standard chow+AET (HFSCEX, n = 30. Microvascular reactivity in response to acetylcholine and sodium nitroprusside and macromolecular permeability increase induced by 30 minutes ischemia followed by reperfusion were assessed on the cheek pouch preparation. Total body fat and aorta eNOS and iNOS expression by immunoblotting assay were evaluated on the experimental day. Compared to HFSC and HFSCEX groups, HF and HFEX ones presented increased visceral fat [(mean±SEM (HF4.9±1.5 g and (HFEX4.7±0.9 g vs. (HFSC*3.0±0.7 g and (HFSCEX*1.9±0.4 g/100 g BW]; impaired endothelial-dependent vasodilatation [Ach 10(-8 M (HF87.9±2.7%; (HFSC*116.7±5.9%; (HFEX*109.1±4.6%; (HFSCEX*105±2.8%; Ach10(-6 M (HF95.3±3.1%; (HFSC*126±6.2%; (HFEX*122.5±2.8%; (HFSCEX*118.1±4.3% and Ach10(-4 M (HF109.5±4.8%; (HFSC*149.6±6.6%; (HFEX*143.5±5.4% and (HFSCEX*139.4±5.2%], macromolecular permeability increase after ischemia/reperfusion [(HF40.5±4.2; (HFSC*19.0±1.6; (HFEX*18.6±2.1 and (HFSCEX* 21.5±3.7 leaks/cm2, decreased eNOS expression, increased leptin and glycaemic levels. Endothelial-independent microvascular

  19. 7,8-Dihydroxyflavone ameliorates high-glucose induced diabetic apoptosis in human retinal pigment epithelial cells by activating TrkB.

    Science.gov (United States)

    Yu, Xiaoyi; Liu, Qiuhong; Wang, Xiaochuan; Liu, Hong; Wang, Yan

    2018-01-01

    In diabetic retinopathy, prolonged high-level blood glucose induced significant impairments among various retinal tissues, including retinal pigment epithelial (RPE) cells. In an in vitro model of human RPE cells, we evaluated whether 7,8-Dihydroxyflavone (DHF) may effectively prevent high glucose-induced diabetic apoptosis among human RPE cells. ARPE-19 cells, a Human RPE cell line, were treated with d-glucose (50 mM) to induce apoptosis in vitro. Prior to glucose, ARPE-19 cells were pre-incubated with various concentrations of DHF. The effect of DHF on d-glucose-induced apoptosis was examined by TUNEL assay, in a concentration-dependent manner. The biological effects of DHF on Caspase-9 (Casp-9) and TrkB signaling pathways in d-glucose-injured ARPE-19 cells were evaluated by qRT-PCR and western blot (WB) assays. A TrkB antagonist, K252a, was also applied in DHF and d-glucose treated ARPE-19 cells. Possible effect of K252a blocking TrkB signaling pathway, thus reversing DHF-modulated apoptosis prevention was also examined by TUNEL and WB assays. DHF ameliorated d-glucose-induced diabetic apoptosis in ARPE-19 cells. Apoptotic factor Casp-9, at both mRNA and protein levels, were drastically inhibited by DHF in d-glucose-injured ARPE-19 cells. Also, DHF activated TrkB signaling pathway through phosphorylation. K252a dramatically reversed the preventive effect of DHF on d-glucose-induced apoptosis in ARPE-19 cells. Further investigation showed that K252a functioned through de-activating or de-phosphorylating TrkB signaling pathway. This work demonstrates that DHF, through activation of TrkB signaling pathway, has a preventive function in d-glucose-induced apoptosis in PRE cells in diabetic retinopathy. Copyright © 2017. Published by Elsevier Inc.

  20. Effect of Functional Bread Rich in Potassium, γ-Aminobutyric Acid and Angiotensin-Converting Enzyme Inhibitors on Blood Pressure, Glucose Metabolism and Endothelial Function: A Double-blind Randomized Crossover Clinical Trial.

    Science.gov (United States)

    Becerra-Tomás, Nerea; Guasch-Ferré, Marta; Quilez, Joan; Merino, Jordi; Ferré, Raimon; Díaz-López, Andrés; Bulló, Mònica; Hernández-Alonso, Pablo; Palau-Galindo, Antoni; Salas-Salvadó, Jordi

    2015-11-01

    Because it has been suggested that food rich in γ-aminobutyric acid (GABA) or angiotensin-converting enzyme inhibitor (ACEI) peptides have beneficial effects on blood pressure (BP) and other cardiovascular risk factors, we tested the effects of low-sodium bread, but rich in potassium, GABA, and ACEI peptides on 24-hour BP, glucose metabolism, and endothelial function.A randomized, double-blind, crossover trial was conducted in 30 patients with pre or mild-to-moderate hypertension, comparing three 4-week nutritional interventions separated by 2-week washout periods. Patients were randomly assigned to consume 120 g/day of 1 of the 3 types of bread for each nutritional intervention: conventional wheat bread (CB), low-sodium wheat bread enriched in potassium (LSB), and low-sodium wheat bread rich in potassium, GABA, and ACEI peptides (LSB + G). For each period, 24-hour BP measurements, in vivo endothelial function, and biochemical samples were obtained.After LSB + G consumption, 24-hour ambulatory BP underwent a nonsignificant greater reduction than after the consumption of CB and LSB (0.26 mm Hg in systolic BP and -0.63 mm Hg in diastolic BP for CB; -0.71 mm Hg in systolic BP and -1.08 mm Hg in diastolic BP for LSB; and -0.75 mm Hg in systolic BP and -2.12 mm Hg in diastolic BP for LSB + G, respectively). Diastolic BP at rest decreased significantly during the LSB + G intervention, although there were no significant differences in changes between interventions. There were no significant differences between interventions in terms of changes in in vivo endothelial function, glucose metabolism, and peripheral inflammatory parameters.Compared with the consumption of CB or LSB, no greater beneficial effects on 24-hour BP, endothelial function, or glucose metabolism were demonstrated after the consumption of LSB + G in a population with pre or mild-to-moderate hypertension. Further studies are warranted to clarify the effect of GABA on BP

  1. Human pericyte-endothelial cell interactions in co-culture models mimicking the diabetic retinal microvascular environment.

    Science.gov (United States)

    Tarallo, Sonia; Beltramo, Elena; Berrone, Elena; Porta, Massimo

    2012-12-01

    Pericytes regulate vascular tone, perfusion pressure and endothelial cell (EC) proliferation in capillaries. Thiamine and benfotiamine counteract high glucose-induced damage in vascular cells. We standardized two human retinal pericyte (HRP)/EC co-culture models to mimic the diabetic retinal microvascular environment. We aimed at evaluating the interactions between co-cultured HRP and EC in terms of proliferation/apoptosis and the possible protective role of thiamine and benfotiamine against high glucose-induced damage. EC and HRP were co-cultured in physiological glucose and stable or intermittent high glucose, with or without thiamine/benfotiamine. No-contact model: EC were plated on a porous membrane suspended into the medium and HRP on the bottom of the same well. Cell-to-cell contact model: EC and HRP were plated on the opposite sides of the same membrane. Proliferation (cell counts and DNA synthesis), apoptosis and tubule formation in Matrigel were assessed. In the no-contact model, stable high glucose reduced proliferation of co-cultured EC/HRP and EC alone and increased co-cultured EC/HRP apoptosis. In the contact model, both stable and intermittent high glucose reduced co-cultured EC/HRP proliferation and increased apoptosis. Stable high glucose had no effects on HRP in separate cultures. Both EC and HRP proliferated better when co-cultured. Thiamine and benfotiamine reversed high glucose-induced damage in all cases. HRP are sensitive to soluble factors released by EC when cultured in high glucose conditions, as suggested by conditioned media assays. In the Matrigel models, addition of thiamine and benfotiamine re-established the high glucose-damaged interactions between EC/HRP and stabilized microtubules.

  2. Perturbation of human coronary artery endothelial cell redox state and NADPH generation by methylglyoxal.

    Directory of Open Access Journals (Sweden)

    Philip E Morgan

    Full Text Available Diabetes is associated with elevated plasma glucose, increased reactive aldehyde formation, oxidative damage, and glycation/glycoxidation of biomolecules. Cellular detoxification of, or protection against, such modifications commonly requires NADPH-dependent reducing equivalents (e.g. GSH. We hypothesised that reactive aldehydes may modulate cellular redox status via the inhibition of NADPH-generating enzymes, resulting in decreased thiol and NADPH levels. Primary human coronary artery endothelial cells (HCAEC were incubated with high glucose (25 mM, 24 h, 37°C, or methylglyoxal (MGO, glyoxal, or glycolaldehyde (100-500 µM, 1 h, 37°C, before quantification of intracellular thiols and NADPH-generating enzyme activities. Exposure to MGO, but not the other species examined, significantly (P<0.05 decreased total thiols (∼35%, further experiments with MGO showed significant losses of GSH (∼40% and NADPH (∼10%; these changes did not result in an immediate loss of cell viability. Significantly decreased (∼10% NADPH-producing enzyme activity was observed for HCAEC when glucose-6-phosphate or 2-deoxyglucose-6-phosphate were used as substrates. Cell lysate experiments showed significant MGO-dose dependent inhibition of glucose-6-phosphate-dependent enzymes and isocitrate dehydrogenase, but not malic enzyme. Analysis of intact cell or lysate proteins showed that arginine-derived hydroimidazolones were the predominant advanced glycation end-product (AGE formed; lower levels of N(ε-(carboxyethyllysine (CEL and N(ε-(carboxymethyllysine (CML were also detected. These data support a novel mechanism by which MGO exposure results in changes in redox status in human coronary artery endothelial cells, via inhibition of NADPH-generating enzymes, with resultant changes in reduced protein thiol and GSH levels. These changes may contribute to the endothelial cell dysfunction observed in diabetes-associated atherosclerosis.

  3. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Text Size: A A A Listen En Español Hyperglycemia (High Blood Glucose) Hyperglycemia is the technical term ... body can't use insulin properly. What Causes Hyperglycemia? A number of things can cause hyperglycemia: If ...

  4. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... for Association Events Messaging Tools Recruiting Advocates Local Market Planning Training Webinars News & Events Advocacy News Call ... Care > Blood Glucose Testing Share: Print Page Text Size: A A A Listen En Español Hyperglycemia (High ...

  5. A highly sensitive electrochemical glucose sensor structuring with nickel hydroxide and enzyme glucose oxidase

    International Nuclear Information System (INIS)

    Mathew, Manjusha; Sandhyarani, N.

    2013-01-01

    Graphical abstract: A combination of Ni 2+ /Ni 3+ redox couple and glucose oxidase has successfully been exploited for the realization of a highly sensitive glucose sensor for the first time. -- Highlights: • A multilayered glucose biosensor with enhanced sensitivity was fabricated. • Combination of Ni 2+ /Ni 3+ redox couple and glucose oxidase has been exploited for the first time. • Exhibits a lower detection limit of 100 nM with a high sensitivity of 16,840 μA mM −1 cm −2 . • The surface shows a low Michaelis–Menten constant value of 2.4 μM. • Detailed mechanism of sensing was proposed and justified. -- Abstract: A multilayered glucose biosensor with enhanced electron transport was fabricated via the sequential electrodeposition of chitosan gold nanocomposite (CGNC) and nickel hydroxide (Ni(OH) 2 ) on a bare gold electrode and subsequent immobilization of glucose oxidase. A thin film of Ni(OH) 2 deposited on CGNC modified gold electrode serves as an electrochemical redox probe as well as a matrix for the immobilization of glucose oxidase retaining its activity. Electron transport property of CGNC has been exploited to enhance the electron transport between the analyte and electrode. Electrochemical characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. Under optimal conditions the biosensor exhibits a linear range from 1 μM to 100 μM with a limit of detection (lod) down to 100 nM. The sensor shows a low Michaelis-Menten constant value of 2.4 μM indicates the high affinity of enzyme to the analyte points to the retained activity of enzyme after immobilization. The present glucose sensor with the high selectivity, sensitivity and stability is promising for practical clinical applications

  6. Local cerebral metabolic rate of glucose (lCMRGlc) in treated and untreated patients with Parkinson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Rougemont, D; Baron, J C; Collard, P; Bustany, P; Comar, D; Agid, Y

    1983-06-01

    Local cerebral metabolic rate of glucose (lCMRGlc) was measured twice, using positron emission tomography and /sup 18/F-Fluoro-2-deoxy-D-glucose (/sup 18/FDG), in 4 patients with Parkinson disease, first unmedicated and then treated with L-DOPA. Despite a dramatic clinical improvement, no significant changes in lCMRGlc could be detected. Moreover, no reproducible differences of lCMRGlc were found between patients with Parkinson disease and with normal brain.

  7. Conditions With High Intracellular Glucose Inhibit Sensing Through Glucose Sensor Snf3 in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Karhumaa, Kaisa; Wu, B.Q.; Kielland-Brandt, Morten

    2010-01-01

    as for amino acids. An alternating-access model of the function of transporter-like sensors has been previously suggested based on amino acid sensing, where intracellular ligand inhibits binding of extracellular ligand. Here we studied the effect of intracellular glucose on sensing of extracellular glucose...... through the transporter-like sensor Snf3 in yeast. Sensing through Snf3 was determined by measuring degradation of Mth1 protein. High intracellular glucose concentrations were achieved by using yeast strains lacking monohexose transporters which were grown on maltose. The apparent affinity...... of extracellular glucose to Snf3 was measured for cells grown in non-fermentative medium or on maltose. The apparent affinity for glucose was lowest when the intracellular glucose concentration was high. The results conform to an alternating-access model for transporter-like sensors. J. Cell. Biochem. 110: 920...

  8. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online Community ... Page Text Size: A A A Listen En Español Hyperglycemia (High Blood Glucose) Hyperglycemia is the technical ...

  9. Regulation of endothelial cell shape and monolayer permeability by atrial natriuretic peptide

    International Nuclear Information System (INIS)

    Lofton-Day, C.E.

    1989-01-01

    Atrial natriuretic peptide (ANP), considered to be an important regulator of intravascular fluid volume, binds specifically to receptors on endothelial cells. In this study, the role of ANP-specific binding was investigated by examining the effect of ANP on the morphology and macromolecular permeability of monolayer cultures of bovine aortic endothelial cells. ANP alone had no observable effect on the monolayers. However, incubation of monolayers with ANP antagonized thrombin- or glucose oxidase-induced cell shape changes and intercellular gap formation. ANP pretreatment also opposed the effect of thrombin and glucose oxidase on actin filament distribution as observed by rhodamine-phalloidin staining and digital image analysis of F0actin staining. In addition, ANP reversed cell shape changes and cytoskeletal alterations induced by thrombin treatment but did not reverse alternations induced by glucose oxidase treatment. ANP significantly reduced increases in monolayer permeability to albumin resulting from thrombin or glucose oxidases treatment. Thrombin caused a 2-fold increase in monolayer permeability to 125 I-labeled albumin, which was abolished by 10 -8 -10 -6 M ANP pretreatment. Glucose oxidase caused similar increases in permeability and was inhibited by ANP at slightly shorter time periods

  10. Effect of aluminum chloride on blood glucose level and lipid profile in normal, diabetic and treated diabetic rats.

    Science.gov (United States)

    Konda, Venugopala Rao; Eerike, Madhavi; Chary, R Prasanth; Arunachalam, Ruckmani; Yeddula, Venkata Ramana; Meti, Vinayak; Devi, T Sobita

    2017-01-01

    The objectives of the study were to assess evaluate the effects of aluminum chloride (AlCl 3 ) on blood glucose and lipid levels in normal, diabetic, and glibenclamide-treated diabetic rats. Forty-two male Wistar rats were divided into seven groups of six each. Group I was normal control, Groups II and III were given AlCl 3 50 and 100 mg/kg, and Group IV to VII were administered with streptozotocin (STZ) (60 mg/kg) intraperitoneally. Group IV was diabetic control, Group V in addition was given AlCl 3 50 mg/kg, Group VI glibenclamide (10 mg/kg), and Group VII glibenclamide and AlCl 3 (50 mg/kg) per-oral daily for 28 days. Blood glucose and lipid levels were estimated at base line, after diabetes was set in and on the last day of study. Histopathological changes in pancreas, liver, and kidney were studied. No significant change was observed in blood glucose and lipid levels in Group I. Group II and III showed a dose-dependent significant increase in blood glucose was observed. Group V had a reduction in blood glucose but not to the nondiabetic level. Group VI had significant reduction in blood sugar. In Group VII, treated with glibenclamide and AlCl 3 , there was no significant change in blood glucose reduction compared to Group VI. Lipid levels were reduced in groups treated with AlCl 3 and glibenclamide and not in other groups. Gross tissue damage was seen in pancreas in STZ group and in liver and kidney in AlCl 3 groups. AlCl 3 administration in Wistar rats caused in significant hyperglycemia in normal rats, hypoglycemia in diabetic rats, and did not influenced hypoglycemic effect of glibenclamide and in addition, resulted in reduction in lipid levels.

  11. A high-throughput colorimetric assay for glucose detection based on glucose oxidase-catalyzed enlargement of gold nanoparticles

    Science.gov (United States)

    Xiong, Yanmei; Zhang, Yuyan; Rong, Pengfei; Yang, Jie; Wang, Wei; Liu, Dingbin

    2015-09-01

    We developed a simple high-throughput colorimetric assay to detect glucose based on the glucose oxidase (GOx)-catalysed enlargement of gold nanoparticles (AuNPs). Compared with the currently available glucose kit method, the AuNP-based assay provides higher clinical sensitivity at lower cost, indicating its great potential to be a powerful tool for clinical screening of glucose.We developed a simple high-throughput colorimetric assay to detect glucose based on the glucose oxidase (GOx)-catalysed enlargement of gold nanoparticles (AuNPs). Compared with the currently available glucose kit method, the AuNP-based assay provides higher clinical sensitivity at lower cost, indicating its great potential to be a powerful tool for clinical screening of glucose. Electronic supplementary information (ESI) available: Experimental section and additional figures. See DOI: 10.1039/c5nr03758a

  12. Heme oxygenase-1 enhances autophagy in podocytes as a protective mechanism against high glucose-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Chenglong [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Zheng, Haining [Department of Hyperbaric Oxygen, Nanjing General Hospital of Nanjing Military Command, Nanjing (China); Huang, Shanshan; You, Na; Xu, Jiarong; Ye, Xiaolong; Zhu, Qun; Feng, Yamin; You, Qiang; Miao, Heng [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Ding, Dafa, E-mail: dingdafa2004@aliyun.com [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China); Lu, Yibing, E-mail: luyibing2004@126.com [Department of Endocrinology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing (China)

    2015-10-01

    Injury and loss of podocytes play vital roles in diabetic nephropathy progression. Emerging evidence suggests autophagy, which is induced by multiple stressors including hyperglycemia, plays a protective role. Meanwhile, heme oxygenase-1 (HO-1) possesses powerful anti-apoptotic properties. Therefore, we investigated the impact of autophagy on podocyte apoptosis under diabetic conditions and its association with HO-1. Mouse podocytes were cultured in vitro; apoptosis was detected by flow cytometry. Transmission electron microscopy and biochemical autophagic flux assays were used to measure the autophagy markers microtubule-associated protein 1 light chain 3-II (LC3-II) and beclin-1. LC3-II and beclin-1 expression peaked 12–24 h after exposing podocytes to high glucose. Inhibition of autophagy with 3-methyladenine or Beclin-1 siRNAs or Atg 5 siRNAs sensitized cells to apoptosis, suggesting autophagy is a survival mechanism. HO-1 inactivation inhibited autophagy, which aggravated podocyte injury in vitro. Hemin-induced autophagy also protected podocytes from hyperglycemia in vitro and was abrogated by HO-1 siRNA. Adenosine monophosphate-activated protein kinase phosphorylation was higher in hemin-treated and lower in HO-1 siRNA-treated podocytes. Suppression of AMPK activity reversed HO-1-mediated Beclin-1 upregulation and autophagy, indicating HO-1-mediated autophagy is AMPK dependent. These findings suggest HO-1 induction and regulation of autophagy are potential therapeutic targets for diabetic nephropathy. - Highlights: • High glucose leads to increased autophagy in podocytes at an early stage. • The early autophagic response protects against high glucose-induced apoptosis. • Heme oxygenase-1 enhances autophagy and decreases high glucose -mediated apoptosis. • Heme oxygenase-1 induces autophagy through the activation of AMPK.

  13. Heme oxygenase-1 enhances autophagy in podocytes as a protective mechanism against high glucose-induced apoptosis

    International Nuclear Information System (INIS)

    Dong, Chenglong; Zheng, Haining; Huang, Shanshan; You, Na; Xu, Jiarong; Ye, Xiaolong; Zhu, Qun; Feng, Yamin; You, Qiang; Miao, Heng; Ding, Dafa; Lu, Yibing

    2015-01-01

    Injury and loss of podocytes play vital roles in diabetic nephropathy progression. Emerging evidence suggests autophagy, which is induced by multiple stressors including hyperglycemia, plays a protective role. Meanwhile, heme oxygenase-1 (HO-1) possesses powerful anti-apoptotic properties. Therefore, we investigated the impact of autophagy on podocyte apoptosis under diabetic conditions and its association with HO-1. Mouse podocytes were cultured in vitro; apoptosis was detected by flow cytometry. Transmission electron microscopy and biochemical autophagic flux assays were used to measure the autophagy markers microtubule-associated protein 1 light chain 3-II (LC3-II) and beclin-1. LC3-II and beclin-1 expression peaked 12–24 h after exposing podocytes to high glucose. Inhibition of autophagy with 3-methyladenine or Beclin-1 siRNAs or Atg 5 siRNAs sensitized cells to apoptosis, suggesting autophagy is a survival mechanism. HO-1 inactivation inhibited autophagy, which aggravated podocyte injury in vitro. Hemin-induced autophagy also protected podocytes from hyperglycemia in vitro and was abrogated by HO-1 siRNA. Adenosine monophosphate-activated protein kinase phosphorylation was higher in hemin-treated and lower in HO-1 siRNA-treated podocytes. Suppression of AMPK activity reversed HO-1-mediated Beclin-1 upregulation and autophagy, indicating HO-1-mediated autophagy is AMPK dependent. These findings suggest HO-1 induction and regulation of autophagy are potential therapeutic targets for diabetic nephropathy. - Highlights: • High glucose leads to increased autophagy in podocytes at an early stage. • The early autophagic response protects against high glucose-induced apoptosis. • Heme oxygenase-1 enhances autophagy and decreases high glucose -mediated apoptosis. • Heme oxygenase-1 induces autophagy through the activation of AMPK

  14. miR-23b-3p induces the cellular metabolic memory of high glucose in diabetic retinopathy through a SIRT1-dependent signalling pathway.

    Science.gov (United States)

    Zhao, Shuzhi; Li, Tao; Li, Jun; Lu, Qianyi; Han, Changjing; Wang, Na; Qiu, Qinghua; Cao, Hui; Xu, Xun; Chen, Haibing; Zheng, Zhi

    2016-03-01

    The mechanisms underlying the cellular metabolic memory induced by high glucose remain unclear. Here, we sought to determine the effects of microRNAs (miRNAs) on metabolic memory in diabetic retinopathy. The miRNA microarray was used to examine human retinal endothelial cells (HRECs) following exposure to normal glucose (N) or high glucose (H) for 1 week or transient H for 2 days followed by N for another 5 days (H→N). Levels of sirtuin 1 (SIRT1) and acetylated-nuclear factor κB (Ac-NF-κB) were examined following transfection with miR-23b-3p inhibitor or with SIRT1 small interfering (si)RNA in the H→N group, and the apoptotic HRECs were determined by flow cytometry. Retinal tissues from diabetic rats were similarly studied following intravitreal injection of miR-23b-3p inhibitor. Chromatin immunoprecipitation (ChIP) analysis was performed to detect binding of NF-κB p65 to the potential binding site of the miR-23b-27b-24-1 gene promoter in HRECs. High glucose increased miR-23b-3p expression, even after the return to normal glucose. Luciferase assays identified SIRT1 as a target mRNA of miR-23b-3p. Reduced miR-23b-3p expression inhibited Ac-NF-κB expression by rescuing SIRT1 expression and also relieved the effect of metabolic memory induced by high glucose in HRECs. The results were confirmed in the retina using a diabetic rat model of metabolic memory. High glucose facilitated the recruitment of NF-κB p65 and promoted transcription of the miR-23b-27b-24-1 gene, which can be suppressed by decreasing miR-23b-3p expression. These studies identify a novel mechanism whereby miR-23b-3p regulates high-glucose-induced cellular metabolic memory in diabetic retinopathy through a SIRT1-dependent signalling pathway.

  15. Verocytotoxin-induced apoptosis of human microvascular endothelial cells.

    Science.gov (United States)

    Pijpers, A H; van Setten, P A; van den Heuvel, L P; Assmann, K J; Dijkman, H B; Pennings, A H; Monnens, L A; van Hinsbergh, V W

    2001-04-01

    The pathogenesis of the epidemic form of hemolytic uremic syndrome is characterized by endothelial cell damage. In this study, the role of apoptosis in verocytotoxin (VT)-mediated endothelial cell death in human glomerular microvascular endothelial cells (GMVEC), human umbilical vein endothelial cells, and foreskin microvascular endothelial cells (FMVEC) was investigated. VT induced apoptosis in GMVEC and human umbilical vein endothelial cells when the cells were prestimulated with the inflammatory mediator tumor necrosis factor-alpha (TNF-alpha). FMVEC displayed strong binding of VT and high susceptibility to VT under basal conditions, which made them suitable for the study of VT-induced apoptosis without TNF-alpha interference. On the basis of functional (flow cytometry and immunofluorescence microscopy using FITC-conjugated annexin V and propidium iodide), morphologic (transmission electron microscopy), and molecular (agarose gel electrophoresis of cellular DNA fragments) criteria, it was documented that VT induced programmed cell death in microvascular endothelial cells in a dose- and time-dependent manner. Furthermore, whereas partial inhibition of protein synthesis by VT was associated with a considerable number of apoptotic cells, comparable inhibition of protein synthesis by cycloheximide was not. This suggests that additional pathways, independent of protein synthesis inhibition, may be involved in VT-mediated apoptosis in microvascular endothelial cells. Specific inhibition of caspases by Ac-Asp-Glu-Val-Asp-CHO, but not by Ac-Tyr-Val-Ala-Asp-CHO, was accompanied by inhibition of VT-induced apoptosis in FMVEC and TNF-alpha-treated GMVEC. These data indicate that VT can induce apoptosis in human microvascular endothelial cells.

  16. Optimization of Glucose oxidase towards oxygen independency and high mediator activity for amperometric glucose determination in diabetes analytics

    OpenAIRE

    Arango Gutierrez, Erik Uwe

    2015-01-01

    Glucose oxidase is an oxidoreductase exhibiting a high β-D-glucose specificity and high stability which renders glucose oxidase well-suited for applications in diabetes care. Nevertheless, GOx activity is highly oxygen dependent which can lead to inaccuracies in amperometric β-D-glucose determinations. Therefore a directed evolution campaign with two rounds of random mutagenesis (SeSaM followed by epPCR), site saturation mutagenesis studies, and one simultaneous site saturation library (OmniC...

  17. [Effect of resveratrol on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment].

    Science.gov (United States)

    Lv, Jia-Shu; Jiang, Xue-Wei; Zhang, Yan; Zhen, Lei

    2017-02-01

    Through a study of the molecular mechanism of the effect of resveratrol(RSV) on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment, the therapeutic effect and molecular mechanism of resveratrol on periodontitis in patients with diabetes mellitus was investigated. Gingival epithelial cells were cultured in vitro; according to the way of action, the cultured cells were divided into control group, high glucose group(HG) and HG+RSV group. The mRNA expression of TLR4 was detected by PCR; The third generation of gingival epithelial cells were pre-treated with or without RSV for 24 h under high glucose conditions, and subsequently treated with LPS at 100 ng/mL for 2 h. ELISA was used to detect the secretion of IL-1 beta, IL-6, IL-8 and TNF- alpha; the activation of TLR4 downstream signaling molecules NF-κB p65, p38 MAPK, and STAT3 was determined by Western blot. SPSS17.0 software package was used for statistical analysis. RSV could reverse the increase of TLR4 level in gingival epithelial cells in high glucose medium.LPS markedly increased the expression and secretion of IL-1β, IL-6, IL-8, and TNF-α in GECs cultured in high glucose medium, which was partly blocked in the presence of RSV. Furthermore, Western blot results showed that RSV significantly suppressed the phosphorylation of TLR4 downstream factors NF-κB p65, p38MAPK, and STAT3. RSV reduces inflammatory cytokine secretion in gingival epithelial cells, through negative regulation of TLR4 signaling pathway.

  18. Glucose uptake and growth of glucose-limited chemostat cultures of Aspergillus niger and a disruptant lacking MstA, a high-affinity glucose transporter

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R; vanKuyk, Patricia A; Poulsen, Bjarne R

    2007-01-01

    This is a study of high-affinity glucose uptake in Aspergillus niger and the effect of disruption of a high-affinity monosaccharide-transporter gene, mstA. The substrate saturation constant (K(s)) of a reference strain was about 15 microM in glucose-limited chemostat culture. Disruption of mst......-affinity uptake system of A. niger. The mstA disruptant and a reference strain were cultivated in glucose-limited chemostat cultures at low, intermediate and high dilution rate (D=0.07 h(-1), 0.14 h(-1) and 0.20 h(-1)). Mycelium harvested from steady-state cultures was subjected to glucose uptake assays...

  19. Effects of spinach nitrate on insulin resistance, endothelial dysfunction markers and inflammation in mice with high-fat and high-fructose consumption

    Directory of Open Access Journals (Sweden)

    Ting Li

    2016-09-01

    Full Text Available Background: Insulin resistance, which is associated with an increased risk of cardiovascular morbidity and mortality, has become a leading nutrition problem. Inorganic nitrate enriched in spinach has been demonstrated to reverse the pathological features of insulin resistance and endothelial dysfunction. However, the effects of a direct intake of nitrate-enriched spinach on insulin resistance and endothelial dysfunction have not been studied. Objective: To investigate the effects of spinach nitrate on insulin resistance, lipid metabolism, endothelial function, and inflammation in mice fed with a high-fat and high-fructose diet. Design: A diet intervention of spinach with or without nitrate was performed in mice. A high-fat and high-fructose diet was used to cause insulin resistance, endothelial dysfunction, and inflammation in mice. The impacts of spinach nitrate on lipid profile, insulin resistance, markers of endothelial function, and inflammation were determined in mice. Results: Spinach nitrate improved the vascular endothelial function of the mice with high-fat and high-fructose consumption, as evidenced by the elevated plasma nitrite level, increased serum nitric oxide (NO level and decreased serum ET-1 level after spinach nitrate intervention. Spinach nitrate also reduced serum triglycerides, total cholesterol, and low-density lipoprotein-cholesterol levels and elevated serum high-density lipoprotein-cholesterol levels in the mice fed with a high-fat and high-fructose diet. Mice receiving spinach with 60 mg/kg of nitrate (1.02±0.34 showed a significantly low homeostasis model assessment-insulin resistance index as compared with the model mice (2.05±0.58, which is indicating that spinach nitrate could effectively improve the insulin resistance. In addition, spinach nitrate remarkably decreased the elevated serum C-reactive protein, tumor necrosis factor α, and interleukin-6 levels induced by a high-fat and high-fructose diet

  20. Nod-like receptor protein 1 inflammasome mediates neuron injury under high glucose.

    Science.gov (United States)

    Meng, Xian-Fang; Wang, Xiao-Lan; Tian, Xiu-Juan; Yang, Zhi-Hua; Chu, Guang-Pin; Zhang, Jing; Li, Man; Shi, Jing; Zhang, Chun

    2014-04-01

    Diabetic encephalopathy is one of the most common complications of diabetes. Inflammatory events during diabetes may be an important mechanism of diabetic encephalopathy. Inflammasome is a multiprotein complex consisting of Nod-like receptor proteins (NLRPs), apoptosis-associated speck-like protein (ASC), and caspase 1 or 5, which functions to switch on the inflammatory process and the release of inflammatory factors. The present study hypothesized that the formation and activation of NLRP1 inflammasome turns on neuroinflammation and neuron injury during hyperglycemia. The results demonstrated that the levels of interleukin-1 beta (IL-1β) were increased in the cortex of streptozocin (STZ)-induced diabetic rats. The levels of mature IL-1β and IL-18 were also elevated in culture medium of neurons treated with high glucose (50 mM). The expression of three essential components of the NLRP1 inflammasome complex, namely, NLRP1, ASC, and caspase 1, was also upregulated in vivo and in vitro under high glucose. Silencing the ASC gene prevented the caspase-1 activation, and inhibiting caspase 1 activity blocked hyperglycemia-induced release of inflammatory factors and neuron injury. Moreover, we found that pannexin 1 mediated the actvitation of NLRP1 inflammasome under high glucose. These results suggest that hyperglycemia induces neuroinflammation through activation of NLRP1 inflammasome, which represents a novel mechanism of diabetes-associated neuron injury.

  1. Infliximab treatment prevents hyperglycemia and the intensification of hepatic gluconeogenesis in an animal model of high fat diet-induced liver glucose overproduction

    Directory of Open Access Journals (Sweden)

    Karissa Satomi Haida

    2012-06-01

    Full Text Available The effect of infliximab on gluconeogenesis in an animal model of diet-induced liver glucose overproduction was investigated. The mice were treated with standard diet (SD group or high fat diet (HFD group. HFD group were randomly divided and treated either with saline (100 µl/dose, ip, twice a day or infliximab (10 µg in 100 µl saline per dose, ip, twice a day, i.e., 0.5 mg/kg per day. SD group also received saline. The treatment with infliximab or saline started on the first day of the introduction of the HFD and was maintained during two weeks. After this period, the mice were fasted (15 h and anesthetized. After laparotomy, blood was collected for glucose determination followed by liver perfusion in which L-alanine (5 mM was used as gluconeogenic substrate. HFD group treated with saline showed higher (p < 0.05 liver glucose production from L-alanine and fasting hyperglycemia. However, these metabolic changes were prevented by infliximab treatment. Therefore, this study suggested that infliximab could prevent the glucose overproduction and hyperglycemia related with glucose intolerance and type 2 diabetes.

  2. Plastic compressed collagen as a novel carrier for expanded human corneal endothelial cells for transplantation.

    Directory of Open Access Journals (Sweden)

    Hannah J Levis

    Full Text Available Current treatments for reversible blindness caused by corneal endothelial cell failure involve replacing the failed endothelium with donor tissue using a one donor-one recipient strategy. Due to the increasing pressure of a worldwide donor cornea shortage there has been considerable interest in developing alternative strategies to treat endothelial disorders using expanded cell replacement therapy. Protocols have been developed which allow successful expansion of endothelial cells in vitro but this approach requires a supporting material that would allow easy transfer of cells to the recipient. We describe the first use of plastic compressed collagen as a highly effective, novel carrier for human corneal endothelial cells. A human corneal endothelial cell line and primary human corneal endothelial cells retained their characteristic cobblestone morphology and expression of tight junction protein ZO-1 and pump protein Na+/K+ ATPase α1 after culture on collagen constructs for up to 14 days. Additionally, ultrastructural analysis suggested a well-integrated endothelial layer with tightly opposed cells and apical microvilli. Plastic compressed collagen is a superior biomaterial in terms of its speed and ease of production and its ability to be manipulated in a clinically relevant manner without breakage. This method provides expanded endothelial cells with a substrate that could be suitable for transplantation allowing one donor cornea to potentially treat multiple patients.

  3. CLINICAL IMPORTANCE OF ENDOTHELIAL DYSFUNCTION AND INSULIN RESISTANCE SYNDROME IN PATIENTS WITH GOUT ASSOCIATED WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    N. N. Kushnarenko

    2015-09-01

    Full Text Available Aim. To study the endothelium status and determine the correlation between endothelial dysfunction and glucose metabolism in men with gout associated with arterial hypertension (HT.Material and methods. Patients (n=175, all are males with gout were enrolled into the study. Ambulatory blood pressure monitoring (ABPM was performed in all patients. Endothelial function was studied in tests with reactive hyperemia (endothelium-dependent reaction and nitroglycerin (endothelium independent reaction in brachial artery by ultrasonic Doppler examination. The level of nitrite-nitrate and endothelin-1 in blood serum was determined by ELISA technique. Fasting blood glucose and oral glucose tolerance tests were performed as well as fasting insulin blood level was determined by immunoenzyme method. Insulin-resistance index (HOMA-IR was calculated. Patients with HOMA- IR>2.77 were considered as insulin-resistant.Results. Patients with gout demonstrated endothelial deterioration associated with activation of nitroxid producing function, elevation in endothelin-1 serum level (1.36 fmol/ml [0.91; 2.32 fmol/ml] vs 0.19 fmol/ml [0.16; 0.27 fmol/ml] in controls, p<0.05 and impairments of endothelium-dependent vasodilation (6.4% [3.3; 7.3%] vs 17.8% [12.7; 23.9%] in controls, p<0.05. The revealed changes were the most marked in patients with gout associated with HT. The correlation between some endothelial dysfunction in- dices and glucose metabolism was observed.Conclusion. ABPM, brachial artery endothelium-dependent vasodilation and glucose metabolism status should be studied in patients with gout. Complex treatment of cardiovascular diseases in patients with gout should include ω-3 polyunsaturated fatty acids, angiotensin receptor antagonists should be used for antihypertensive therapy.

  4. GABA dramatically improves glucose tolerance in streptozotocin-induced diabetic rats fed with high-fat diet.

    Science.gov (United States)

    Sohrabipour, Shahla; Sharifi, Mohammad Reza; Talebi, Ardeshir; Sharifi, Mohammadreza; Soltani, Nepton

    2018-05-05

    Skeletal muscle, hepatic insulin resistance, and beta cell dysfunction are the characteristic pathophysiological features of type 2 diabetes mellitus. GABA has an important role in pancreatic islet cells. The present study attempted to clarify the possible mechanism of GABA to improve glucose tolerance in a model of type 2 diabetes mellitus in rats. Fifty Wistar rats were divided into five groups: NDC that was fed the normal diet, CD which received a high-fat diet with streptozotocin, CD-GABA animals that received GABA via intraperitoneal injection, plus CD-Ins1 and CD-Ins2 groups which were treated with low and high doses of insulin, respectively. Body weight and blood glucose were measured weekly. Intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (ITT), urine volume, amount of water drinking, and food intake assessments were performed monthly. The hyperinsulinemic euglycemic clamp was done for assessing insulin resistance. Plasma insulin and glucagon were measured. Abdominal fat was measured. Glucagon receptor, Glucose 6 phosphatase, Phosphoenolpyruvate carboxykinase genes expression were evaluated in liver and Glucose transporter 4 (GLUT4) genes expression and protein translocation were evaluated in the muscle. GABA or insulin therapy improved blood glucose, insulin level, IPGTT, ITT, gluconeogenesis pathway, Glucagon receptor, body weight and body fat in diabetic rats. GLUT4 gene and protein expression increased. GABA whose beneficial effect was comparable to that of insulin, also increased glucose infusion rate during an euglycemic clamp. GABA could improve insulin resistance via rising GLUT4 and also decreasing the gluconeogenesis pathway and Glucagon receptor gene expression. Copyright © 2018. Published by Elsevier B.V.

  5. Portulaca oleracea Ameliorates Diabetic Vascular Inflammation and Endothelial Dysfunction in db/db Mice

    Science.gov (United States)

    Lee, An Sook; Lee, Yun Jung; Lee, So Min; Yoon, Jung Joo; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2012-01-01

    Type 2 diabetes is associated with significantly accelerated rates of micro- and macrovascular complications such as diabetic vascular inflammation and endothelial dysfunction. In the present study, we investigated the protective effect of the aqueous extract of Portulaca oleracea L. (AP), an edible plant used as a folk medicine, on diabetic vascular complications. The db/db mice were treated with AP (300 mg/kg/day, p.o.) for 10 weeks, and AP treatment markedly lowered blood glucose, plasma triglyceride, plasma level of LDL-cholesterol, and systolic blood pressure in diabetic db/db mice. Furthermore, AP significantly increased plasma level of HDL-cholesterol and insulin level. The impairment of ACh- and SNP-induced vascular relaxation of aortic rings were ameliorated by AP treatment in diabetic db/db mice. This study also showed that overexpression of VCAM-1, ICAM-1, E-selectin, MMP-2, and ET-1 were observed in aortic tissues of untreated db/db mice, which were significantly suppressed by treatment with AP. We also found that the insulin immunoreactivity of the pancreatic islets remarkably increased in AP treated db/db mice compared with untreated db/db mice. Taken together, AP suppresses hyperglycemia and diabetic vascular inflammation, and prevents the development of diabetic endothelial dysfunction for the development of diabetes and its vascular complications. PMID:22474522

  6. Chronic administration of the probiotic kefir improves the endothelial function in spontaneously hypertensive rats.

    Science.gov (United States)

    Friques, Andreia G F; Arpini, Clarisse M; Kalil, Ieda C; Gava, Agata L; Leal, Marcos A; Porto, Marcella L; Nogueira, Breno V; Dias, Ananda T; Andrade, Tadeu U; Pereira, Thiago Melo C; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

    2015-12-30

    The beverage obtained by fermentation of milk with kefir grains, a complex matrix containing acid bacteria and yeasts, has been shown to have beneficial effects in various diseases. However, its effects on hypertension and endothelial dysfunction are not yet clear. In this study, we evaluated the effects of kefir on endothelial cells and vascular responsiveness in spontaneously hypertensive rats (SHR). SHR were treated with kefir (0.3 mL/100 g body weight) for 7, 15, 30 and 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Vascular endothelial function was evaluated in aortic rings through the relaxation response to acetylcholine (ACh). The balance between reactive oxygen species (ROS) and nitric oxide (NO) synthase was evaluated through specific blockers in the ACh-induced responses and through flow cytometry in vascular tissue. Significant effects of kefir were observed only after treatment for 60 days. The high blood pressure and tachycardia exhibited by the SHR were attenuated by approximately 15 % in the SHR-kefir group. The impaired ACh-induced relaxation of the aortic rings observed in the SHR (37 ± 4 %, compared to the Wistar rats: 74 ± 5 %), was significantly attenuated in the SHR group chronically treated with kefir (52 ± 4 %). The difference in the area under the curve between before and after the NADPH oxidase blockade or NO synthase blockade of aortic rings from SHR were of approximately +90 and -60 %, respectively, when compared with Wistar rats. In the aortic rings from the SHR-kefir group, these values were reduced to +50 and -40 %, respectively. Flow cytometric analysis of aortic endothelial cells revealed increased ROS production and decreased NO bioavailability in the SHR, which were significantly attenuated by the treatment with kefir. Scanning electronic microscopy showed vascular endothelial surface injury in SHR, which was partially protected following administration of kefir for 60 days. In addition, the

  7. Effect of Ethanolic Extract of Emblica officinalis (Amla on Glucose Homeostasis in Rats Fed with High Fat Diet

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    Pallavi S. Kanthe

    2017-07-01

    Full Text Available Background: Emblica officinalis contains many biological active components which are found to have some medicinal properties against diseases. Aim and Objectives: To assess hypolipidemic and glucose regulatory actions of Ethanolic Extract of Emblica officinalis (EEO on High Fat Diet (HFD fed experimental rats. Material and Methods: Twenty four rats were divided into four groups, having six rats in each group as following; Group I- Control (20% fat; Group II (EEO 100 mg/kg/b w; Group III (30% fat and Group IV (30% fat + EEO 100 mg/kg/b w. The treatment was continued for 21 days. Gravimetric parameters and lipid profiles of all the groups were measured. Oral Glucose Tolerance Test (OGTT, fasting and postprandial glucose and fasting insulin levels were estimated. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR was calculated. Statistical analysis was done. Results: Significant alteration in serum lipid profile, fasting and post prandial blood glucose levels and fasting insulin level were observed in rats of Group III fed with high fat diet. Supplementation of EEO improved both of glycemic and lipid profiles in rats of Group IV fed with high fat diet. Conclusion: Results from the study indicate the beneficial role of EEO on dyslipidemia and glucose homeostasis in rats treated with high fat diet.

  8. High glucose impairs superoxide production from isolated blood neutrophils

    DEFF Research Database (Denmark)

    Perner, A; Nielsen, S E; Rask-Madsen, J

    2003-01-01

    Superoxide (O(2)(-)), a key antimicrobial agent in phagocytes, is produced by the activity of NADPH oxidase. High glucose concentrations may, however, impair the production of O(2)(-) through inhibition of glucose-6-phosphate dehydrogenase (G6PD), which catalyzes the formation of NADPH. This study...... measured the acute effects of high glucose or the G6PD inhibitor dehydroepiandrosterone (DHEA) on the production of O(2)(-) from isolated human neutrophils....

  9. Protective role of morin, a flavonoid, against high glucose induced oxidative stress mediated apoptosis in primary rat hepatocytes.

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    Radhika Kapoor

    Full Text Available Apoptosis is an early event of liver damage in diabetes and oxidative stress has been linked to accelerate the apoptosis in hepatocytes. Therefore, the compounds that can scavenge ROS may confer regulatory effects on high-glucose induced apoptosis. In the present study, primary rat hepatocytes were exposed to high concentration (40 mM of glucose. At this concentration decreased cell viability and enhanced ROS generation was observed. Depleted antioxidant status of hepatocytes under high glucose stress was also observed as evident from transcriptional level and activities of antioxidant enzymes. Further, mitochondrial depolarisation was accompanied by the loss of mitochondrial integrity and altered expression of Bax and Bcl-2. Increased translocation of apoptotic proteins like AIF (Apoptosis inducing factor & Endo-G (endonuclease-G from its resident place mitochondria to nucleus was also observed. Cyt-c residing in the inter-membrane space of mitochondria also translocated to cytoplasm. These apoptotic proteins initiated caspase activation, DNA fragmentation, chromatin condensation, increased apoptotic DNA content in glucose treated hepatocytes, suggesting mitochondria mediated apoptotic mode of cell death. Morin, a dietary flavonoid from Psidium guajava was effective in increasing the cell viability and decreasing the ROS level. It maintained mitochondrial integrity, inhibited release of apoptotic proteins from mitochondria, prevented DNA fragmentation, chromatin condensation and hypodiploid DNA upon exposure to high glucose. This study confirms the capacity of dietary flavonoid Morin in regulating apoptosis induced by high glucose via mitochondrial mediated pathway through intervention of oxidative stress.

  10. Activation of K+ channels and Na+/K+ ATPase prevents aortic endothelial dysfunction in 7-day lead-treated rats

    International Nuclear Information System (INIS)

    Fiorim, Jonaina; Ribeiro Júnior, Rogério Faustino; Azevedo, Bruna Fernades; Simões, Maylla Ronacher; Padilha, Alessandra Simão; Stefanon, Ivanita; Alonso, Maria Jesus; Salaices, Mercedes; Vassallo, Dalton Valentim

    2012-01-01

    Seven day exposure to a low concentration of lead acetate increases nitric oxide bioavailability suggesting a putative role of K + channels affecting vascular reactivity. This could be an adaptive mechanism at the initial stages of toxicity from lead exposure due to oxidative stress. We evaluated whether lead alters the participation of K + channels and Na + /K + -ATPase (NKA) on vascular function. Wistar rats were treated with lead (1st dose 4 μg/100 g, subsequent doses 0.05 μg/100 g, im, 7 days) or vehicle. Lead treatment reduced the contractile response of aortic rings to phenylephrine (PHE) without changing the vasodilator response to acetylcholine (ACh) or sodium nitroprusside (SNP). Furthermore, this treatment increased basal O 2 − production, and apocynin (0.3 μM), superoxide dismutase (150 U/mL) and catalase (1000 U/mL) reduced the response to PHE only in the treated group. Lead also increased aortic functional NKA activity evaluated by K + -induced relaxation curves. Ouabain (100 μM) plus L-NAME (100 μM), aminoguanidine (50 μM) or tetraethylammonium (TEA, 2 mM) reduced the K + -induced relaxation only in lead-treated rats. When aortic rings were precontracted with KCl (60 mM/L) or preincubated with TEA (2 mM), 4-aminopyridine (4-AP, 5 mM), iberiotoxin (IbTX, 30 nM), apamin (0.5 μM) or charybdotoxin (0.1 μM), the ACh-induced relaxation was more reduced in the lead-treated rats. Additionally, 4-AP and IbTX reduced the relaxation elicited by SNP more in the lead-treated rats. Results suggest that lead treatment promoted NKA and K + channels activation and these effects might contribute to the preservation of aortic endothelial function against oxidative stress. -- Highlights: ► Increased free radicals production ► Increased Na + /K + ATPase activity ► Promotes activation of the K + channels and reduced vascular reactivity ► These effects preserve endothelial function against oxidative stress. ► Low concentrations constitute environmental

  11. Tetramethylpyrazine Protects Against Oxygen-Glucose Deprivation-Induced Brain Microvascular Endothelial Cells Injury via Rho/Rho-kinase Signaling Pathway.

    Science.gov (United States)

    Yang, Guang; Qian, Chen; Wang, Ning; Lin, Chenyu; Wang, Yan; Wang, Guangyun; Piao, Xinxin

    2017-05-01

    Tetramethylpyrazine (TMP, also known as Ligustrazine), which is isolated from Chinese Herb Medicine Ligustium wollichii Franchat (Chuan Xiong), has been widely used in China for the treatment of ischemic stroke by Chinese herbalists. Brain microvascular endothelial cells (BMECs) are the integral parts of the blood-brain barrier (BBB), protecting BMECs against oxygen-glucose deprivation (OGD) which is important for the treatment of ischemic stroke. Here, we investigated the protective mechanisms of TMP, focusing on OGD-injured BMECs and the Rho/Rho-kinase (Rho-associated kinases, ROCK) signaling pathway. The model of OGD-injured BMECs was established in this study. BMECs were identified by von Willebrand factor III staining and exposed to fasudil, or TMP at different concentrations (14.3, 28.6, 57.3 µM) for 2 h before 24 h of OGD injury. The effect of each treatment was examined by cell viability assays, measurement of intracellular reactive oxygen species (ROS), and transendothelial electric resistance and western blot analysis (caspase-3, endothelial nitric oxide synthase (eNOS), RhoA, Rac1). Our results show that TMP significantly attenuated apoptosis and the permeability of BMECs induced by OGD. In addition, TMP could notably down-regulate the characteristic proteins in Rho/ROCK signaling pathway such as RhoA and Rac1, which triggered abnormal changes of eNOS and ROS, respectively. Altogether, our results show that TMP has a strong protective effect against OGD-induced BMECs injury and suggest that the mechanism might be related to the inhibition of the Rho/ROCK signaling pathway.

  12. Endothelial Fcγ Receptor IIB Activation Blunts Insulin Delivery to Skeletal Muscle to Cause Insulin Resistance in Mice

    Science.gov (United States)

    Tanigaki, Keiji; Chambliss, Ken L.; Yuhanna, Ivan S.; Sacharidou, Anastasia; Ahmed, Mohamed; Atochin, Dmitriy N.; Huang, Paul L.

    2016-01-01

    Modest elevations in C-reactive protein (CRP) are associated with type 2 diabetes. We previously revealed in mice that increased CRP causes insulin resistance and mice globally deficient in the CRP receptor Fcγ receptor IIB (FcγRIIB) were protected from the disorder. FcγRIIB is expressed in numerous cell types including endothelium and B lymphocytes. Here we investigated how endothelial FcγRIIB influences glucose homeostasis, using mice with elevated CRP expressing or lacking endothelial FcγRIIB. Whereas increased CRP caused insulin resistance in mice expressing endothelial FcγRIIB, mice deficient in the endothelial receptor were protected. The insulin resistance with endothelial FcγRIIB activation was due to impaired skeletal muscle glucose uptake caused by attenuated insulin delivery, and it was associated with blunted endothelial nitric oxide synthase (eNOS) activation in skeletal muscle. In culture, CRP suppressed endothelial cell insulin transcytosis via FcγRIIB activation and eNOS antagonism. Furthermore, in knock-in mice harboring constitutively active eNOS, elevated CRP did not invoke insulin resistance. Collectively these findings reveal that by inhibiting eNOS, endothelial FcγRIIB activation by CRP blunts insulin delivery to skeletal muscle to cause insulin resistance. Thus, a series of mechanisms in endothelium that impairs insulin movement has been identified that may contribute to type 2 diabetes pathogenesis. PMID:27207525

  13. Mouse lung contains endothelial progenitors with high capacity to form blood and lymphatic vessels

    Directory of Open Access Journals (Sweden)

    Barleon Bernhard

    2010-07-01

    Full Text Available Abstract Background Postnatal endothelial progenitor cells (EPCs have been successfully isolated from whole bone marrow, blood and the walls of conduit vessels. They can, therefore, be classified into circulating and resident progenitor cells. The differentiation capacity of resident lung endothelial progenitor cells from mouse has not been evaluated. Results In an attempt to isolate differentiated mature endothelial cells from mouse lung we found that the lung contains EPCs with a high vasculogenic capacity and capability of de novo vasculogenesis for blood and lymph vessels. Mouse lung microvascular endothelial cells (MLMVECs were isolated by selection of CD31+ cells. Whereas the majority of the CD31+ cells did not divide, some scattered cells started to proliferate giving rise to large colonies (> 3000 cells/colony. These highly dividing cells possess the capacity to integrate into various types of vessels including blood and lymph vessels unveiling the existence of local microvascular endothelial progenitor cells (LMEPCs in adult mouse lung. EPCs could be amplified > passage 30 and still expressed panendothelial markers as well as the progenitor cell antigens, but not antigens for immune cells and hematopoietic stem cells. A high percentage of these cells are also positive for Lyve1, Prox1, podoplanin and VEGFR-3 indicating that a considerabe fraction of the cells are committed to develop lymphatic endothelium. Clonogenic highly proliferating cells from limiting dilution assays were also bipotent. Combined in vitro and in vivo spheroid and matrigel assays revealed that these EPCs exhibit vasculogenic capacity by forming functional blood and lymph vessels. Conclusion The lung contains large numbers of EPCs that display commitment for both types of vessels, suggesting that lung blood and lymphatic endothelial cells are derived from a single progenitor cell.

  14. Signaling hierarchy regulating human endothelial cell development.

    Science.gov (United States)

    Kelly, Melissa A; Hirschi, Karen K

    2009-05-01

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these studies. Using human embryonic stem cells as a model system, we were able to reproducibly and robustly generate differentiated endothelial cells via coculture on OP9 marrow stromal cells. We found that, in contrast to studies in the mouse, bFGF and VEGF had no specific effects on the initiation of human vasculogenesis. However, exogenous Ihh promoted endothelial cell differentiation, as evidenced by increased production of cells with cobblestone morphology that coexpress multiple endothelial-specific genes and proteins, form lumens, and exhibit DiI-AcLDL uptake. Inhibition of BMP signaling using Noggin or BMP4, specifically, using neutralizing antibodies suppressed endothelial cell formation; whereas, addition of rhBMP4 to cells treated with the hedgehog inhibitor cyclopamine rescued endothelial cell development. Our studies revealed that Ihh promoted human endothelial cell differentiation from pluripotent hES cells via BMP signaling, providing novel insights applicable to modulating human endothelial cell formation and vascular regeneration for human clinical therapies.

  15. Influence of C-Peptide on Glucose Utilisation

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    B. Wilhelm

    2008-01-01

    Full Text Available During the recent years, multiple studies demonstrated that C-peptide is not an inert peptide, but exerts important physiological effects. C-peptide binds to cell membranes, stimulates the Na,K-ATPase and the endothelial nitric oxide (NO synthase. Moreover, there is evidence that C-peptide decreases glomerular hyperfiltration and increases glucose utilisation. Nevertheless, there is still limited knowledge concerning mechanisms leading to an increased glucose utilisation either in rats or in humans. The aim of this paper is to give an overview over the published studies regarding C-peptide and glucose metabolism from in vitro studies to longer lasting studies in humans.

  16. Optimization of high-rate TN removal in a novel constructed wetland integrated with microelectrolysis system treating high-strength digestate supernatant.

    Science.gov (United States)

    Guo, Luchen; He, Keli; Wu, Shubiao; Sun, Hao; Wang, Yanfei; Huang, Xu; Dong, Renjie

    2016-08-01

    The potential of high-rate TN removal in three aerated horizontal subsurface-flow constructed wetlands to treat high-strength anaerobic digestate supernatant was evaluated. Different strategies of intermittent aeration and effluent recirculation were applied to compare their effect on nitrogen depuration performance. Additional glucose supply and iron-activated carbon based post-treatment systems were established and examined, respectively, to further remove nitrate that accumulated in the effluents from aerated wetlands. The results showed that intermittent aeration (1 h on:1 h off) significantly improved nitrification with ammonium removal efficiency of 90% (18.1 g/(m(2)·d)), but limited TN removal efficiency (53%). Even though effluent recirculation (a ratio of 1:1) increased TN removal from 53% to 71%, the effluent nitrate concentration was still high. Additional glucose was used as a post-treatment option and further increased the TN removal to 82%; however, this implementation caused additional organic pollution. Furthermore, the iron-activated carbon system stimulated with a microelectrolysis process achieved greater than 85% effluent nitrate removal and resulted in 86% TN removal. Considering the high TN removal rate, aerated constructed wetlands integrated with a microelectrolysis-driven system show great potential for treating high-strength digestate supernatant. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Underestimation of glucose turnover corrected with high-performance liquid chromatography purification of [6-3H]glucose

    International Nuclear Information System (INIS)

    Schwenk, W.F.; Butler, P.C.; Haymond, M.W.; Rizza, R.A.

    1990-01-01

    We have recently reported that during infusion of commercially available [6-3H]glucose, a radioactive nonglucose contaminant may accumulate in plasma causing errors in the measurement of glucose turnover. To determine whether purification of this tracer by HPLC (high-performance liquid chromatography) before infusion would eliminate the contaminant in plasma and remove the underestimation of glucose turnover reported during hyperinsulinemia, four normal subjects each underwent two 5-h euglycemic clamps during infusion of insulin (1 mU.kg-1.min-1). Glucose turnover was measured with either commercially available [6-3H]glucose or with HPLC-purified [6-3H]glucose. HPLC analysis of samples from the clamps done with commercially available [6-3H]glucose showed that 9.7% of the infused tracer and 26% of the plasma glucose 3H radioactivity were contaminants. In contrast, no contaminant was observed in the plasma during infusion of HPLC-purified [6-3H]glucose. During the last hour of the clamp, mean glucose turnover using commercially available [6-3H]glucose was less (P less than 0.01) than the mean glucose infusion rate (7.6 +/- 0.3 vs. 10.5 +/- 0.3 mg.kg-1.min-1) yielding apparent negative (P less than 0.001) hepatic glucose release. In contrast, when HPLC-purified [6-3H]glucose was employed, glucose turnover equaled the glucose infusion rate (10.4 +/- 0.9 vs. 10.2 +/- 0.9 mg.kg-1.min-1) and hepatic glucose release was no longer negative. We conclude that removal of a tritiated nonglucose contaminant in [6-3H]glucose by HPLC yields correct estimations of glucose turnover at steady state

  18. Oral Mucosa Harbors a High Frequency of Endothelial Cells: A Novel Postnatal Cell Source for Angiogenic Regeneration.

    Science.gov (United States)

    Zhou, Jian; Rogers, Jason H; Lee, Scott H; Sun, DongMing; Yao, Hai; Mao, Jeremy J; Kong, Kimi Y

    2017-01-15

    Endothelial progenitor cells/endothelial cells (EPCs/ECs) have great potential to treat pathological conditions such as cardiac infarction, muscle ischemia, and bone fractures, but isolation of EPC/ECs from existing cell sources is challenging due to their low EC frequency. We have isolated endothelial progenitor (EP)-like cells from rat oral mucosa and characterized their yield, immunophenotype, growth, and in vivo angiogenic potential. The frequency of EP-like cells derived from oral mucosa is thousands of folds higher than EPCs derived from donor-match bone marrow samples. EP-like cells from oral mucosa were positive for EC markers CD31, VE-Cadherin, and VEGFR2. Oral mucosa-derived EP-like cells displayed robust uptake of acetylated low-density lipoprotein and formed stable capillary networks in Matrigel. Subcutaneously implanted oral mucosa-derived EP-like cells anastomosed with host blood vessels, implicating their ability to elicit angiogenesis. Similar to endothelial colony-forming cells, EP-like cells from oral mucosa have a significantly higher proliferative rate than human umbilical vein endothelial cells. These findings identify a putative EPC source that is easily accessible in the oral cavity, potentially from discarded tissue specimens, and yet with robust yield and potency for angiogenesis in tissue and organ regeneration.

  19. Effect of lycium barbarum polysaccharides on high glucose-induced retinal ganglion cell apoptosis, gene expression and delayed rectifier potassium current

    Directory of Open Access Journals (Sweden)

    Xiao-Fei Ma

    2017-05-01

    Full Text Available Objective: To study the effect of lycium barbarum polysaccharides (LBP on high glucoseinduced retinal ganglion cell apoptosis, gene expression and delayed rectifier potassium current. Methods: RGC-5 retinal ganglion cell lines were cultured and divided into control group, high glucose group and LBP group that were treated with normal DMEM, highglucose DMEM as well as high-glucose DMEM containing 500 ng/mL LBP respectively. After treatment, the Annexin V-FITC/PI kits were used to measure the number of apoptotic cells, fluorescence quantitative PCR kits were used to determine the expression of apoptosis genes and antioxidant genes, and patch clamp was used to test delayed rectifier potassium current. Results: 12, 24, 36 and 48 h after intervention, the number of apoptotic cells of high glucose group was significantly higher than that of control group, and the number of apoptotic cells of LBP group was significantly lower than that of high glucose group (P<0.05; 24 and 48 h after intervention, c-fos, c-jun, caspase-3, caspase-9, Nrf-2, NQO1 and HO-1 mRNA expression as well as potassium current amplitude (IK and maximum conductance (Gmax of high glucose group were significantly higher than those of control group while half maximum activation voltage (V1/2 was significantly lower than that of control group (P<0.05; c-fos, c-jun, caspase-3 and caspase-9 mRNA expression as well as IK and Gmax of LBP group were significantly lower than those of high glucose group, while Nrf-2, NQO1 and HO-1 mRNA expression as well as V1/2 of LBP group were significantly higher than those of high glucose group (P<0.05. Conclusions: LBP can reduce the high glucose-induced retinal ganglion cell apoptosis and inhibit the delayed rectifier potassium current amplitude.

  20. Designing a highly active soluble PQQ-glucose dehydrogenase for efficient glucose biosensors and biofuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Durand, Fabien [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France); Stines-Chaumeil, Claire [Universite de Bordeaux, CNRS, Institut de Biochimie et de Genetique Cellulaires, 1 rue Camille Saint Saens, 33077 Bordeaux Cedex (France); Flexer, Victoria [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France); Andre, Isabelle [Universite de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse (France); CNRS, UMR5504, F-31400 Toulouse (France); INRA, UMR 792 Ingenierie des Systemes Biologiques et des Procedes, F-31400 Toulouse (France); Mano, Nicolas, E-mail: mano@crpp-bordeaux.cnrs.fr [Universite de Bordeaux, Centre de Recherche Paul Pascal (CRPP), UPR 8641, Avenue Albert Schweitzer, 33600 Pessac (France)

    2010-11-26

    Research highlights: {yields} A new mutant of PQQ-GDH designed for glucose biosensors application. {yields} First mutant of PQQ-GDH with higher activity for D-glucose than the Wild type. {yields} Position N428 is a key point to increase the enzyme activity. {yields} Molecular modeling shows that the N428 C mutant displays a better interaction for PQQ than the WT. -- Abstract: We report for the first time a soluble PQQ-glucose dehydrogenase that is twice more active than the wild type for glucose oxidation and was obtained by combining site directed mutagenesis, modelling and steady-state kinetics. The observed enhancement is attributed to a better interaction between the cofactor and the enzyme leading to a better electron transfer. Electrochemical experiments also demonstrate the superiority of the new mutant for glucose oxidation and make it a promising enzyme for the development of high-performance glucose biosensors and biofuel cells.

  1. High Glucose Promotes Aβ Production by Inhibiting APP Degradation

    Science.gov (United States)

    Zhang, Shuting; Song, Weihong

    2013-01-01

    Abnormal deposition of neuriticplaques is the uniqueneuropathological hallmark of Alzheimer’s disease (AD).Amyloid β protein (Aβ), the major component of plaques, is generated from sequential cleavage of amyloidβ precursor protein (APP) by β-secretase and γ-secretase complex. Patients with diabetes mellitus (DM), characterized by chronic hyperglycemia,have increased risk of AD development.However, the role of high blood glucose in APP processing and Aβ generation remains elusive. In this study, we investigated the effect of high glucose on APP metabolism and Aβ generation in cultured human cells. We found that high glucose treatment significantly increased APP protein level in both neuronal-like and non-neuronal cells, and promoted Aβ generation. Furthermore, we found that high glucose-induced increase of APP level was not due to enhancement of APP gene transcription but resulted from inhibition of APP protein degradation. Taken together, our data indicated that hyperglycemia could promote AD pathogenesis by inhibiting APP degradation and enhancing Aβ production. More importantly, the elevation of APP level and Aβ generation by high glucose was caused by reduction of APP turnover rate.Thus,our study provides a molecular mechanism of increased risk of developing AD in patients withDMand suggests thatglycemic control might be potentially beneficial for reducing the incidence of AD in diabetic patients and delaying the AD progression. PMID:23894546

  2. Fiber-rich diet with brown rice improves endothelial function in type 2 diabetes mellitus: A randomized controlled trial.

    Science.gov (United States)

    Kondo, Keiko; Morino, Katsutaro; Nishio, Yoshihiko; Ishikado, Atsushi; Arima, Hisatomi; Nakao, Keiko; Nakagawa, Fumiyuki; Nikami, Fumio; Sekine, Osamu; Nemoto, Ken-Ichi; Suwa, Makoto; Matsumoto, Motonobu; Miura, Katsuyuki; Makino, Taketoshi; Ugi, Satoshi; Maegawa, Hiroshi

    2017-01-01

    A fiber-rich diet has a cardioprotective effect, but the mechanism for this remains unclear. We hypothesized that a fiber-rich diet with brown rice improves endothelial function in patients with type 2 diabetes mellitus. Twenty-eight patients with type 2 diabetes mellitus at a single general hospital in Japan were randomly assigned to a brown rice (n = 14) or white rice (n = 14) diet and were followed for 8 weeks. The primary outcome was changes in endothelial function determined from flow debt repayment by reactive hyperemia using strain-gauge plethysmography in the fasting state. Secondary outcomes were changes in HbA1c, postprandial glucose excursions, and markers of oxidative stress and inflammation. The area under the curve for glucose after ingesting 250 kcal of assigned rice was compared between baseline (T0) and at the end of the intervention (T1) to estimate glucose excursions in each group. Improvement in endothelial function, assessed by fasting flow debt repayment (20.4% vs. -5.8%, p = 0.004), was significantly greater in the brown rice diet group than the white rice diet group, although the between-group difference in change of fiber intake was small (5.6 g/day vs. -1.2 g/day, pdiet group compared with the white rice diet group (0.01 μg/L vs. -0.04 μg/L, p = 0.063). The area under the curve for glucose was subtly but consistently lower in the brown rice diet group (T0: 21.4 mmol/L*h vs. 24.0 mmol/L*h, p = 0.043, T1: 20.4 mmol/L*h vs. 23.3 mmol/L*h, p = 0.046) without changes in HbA1c. Intervention with a fiber-rich diet with brown rice effectively improved endothelial function, without changes in HbA1c levels, possibly through reducing glucose excursions.

  3. Evaluation of the EndoPAT as a Tool to Assess Endothelial Function

    Directory of Open Access Journals (Sweden)

    M. Moerland

    2012-01-01

    Endothelial function was stable over a longer period of time in renally impaired patients (coefficient of variation 13%. Endothelial function in renally impaired and type 2 diabetic patients was not decreased compared to healthy volunteers (2.9±1.4 and 1.8±0.3, resp., versus 1.8±0.5, P>0.05. The EndoPAT did not detect an effect of robust interventions on endothelial function in healthy volunteers (glucose load: change from baseline 0.08±0.50, 95% confidence interval −0.44 to 0.60; smoking: change from baseline 0.49±0.92, 95% confidence interval −0.47 to 1.46. This suggests that at present the EndoPAT might not be suitable to assess (changes in endothelial function in early-phase clinical pharmacology studies. Endothelial function as measured by the EndoPAT could be physiologically different from endothelial function as measured by conventional techniques. This should be investigated carefully before the EndoPAT can be considered a useful tool in drug development or clinical practice.

  4. Suppression of endothelial t-PA expression by prolonged high laminar shear stress

    International Nuclear Information System (INIS)

    Ulfhammer, Erik; Carlstroem, Maria; Bergh, Niklas; Larsson, Pia; Karlsson, Lena; Jern, Sverker

    2009-01-01

    Primary hypertension is associated with an impaired capacity for acute release of endothelial tissue-type plasminogen activator (t-PA), which is an important local protective response to prevent thrombus extension. As hypertensive vascular remodeling potentially results in increased vascular wall shear stress, we investigated the impact of shear on regulation of t-PA. Cultured human endothelial cells were exposed to low (≤1.5 dyn/cm 2 ) or high (25 dyn/cm 2 ) laminar shear stress for up to 48 h in two different experimental models. Using real-time RT-PCR and ELISA, shear stress was observed to time and magnitude-dependently suppress t-PA transcript and protein secretion to approximately 30% of basal levels. Mechanistic experiments revealed reduced nuclear protein binding to the t-PA specific CRE element (EMSA) and an almost completely abrogated shear response with pharmacologic JNK inhibition. We conclude that prolonged high laminar shear stress suppresses endothelial t-PA expression and may therefore contribute to the enhanced risk of arterial thrombosis in hypertensive disease.

  5. Heat shock protein 70 modulates neural progenitor cells dynamics in human neuroblastoma SH-SY5Y cells exposed to high glucose content.

    Science.gov (United States)

    Salimi, Leila; Rahbarghazi, Reza; Jafarian, Vahab; Biray Avci, Çıgır; Goker Bagca, Bakiye; Pinar Ozates, Neslihan; Khaksar, Majid; Nourazarian, Alireza

    2018-01-18

    In the current experiment, detrimental effects of high glucose condition were investigated on human neuroblastoma cells. Human neuroblastoma cell line SH-SY5Y were exposed to 5, 40, and 70 mM glucose over a period of 72 h. Survival rate and the proliferation of cells were analyzed by MTT and BrdU incorporation assays. Apoptosis was studied by the assays of flow cytometry and PCR array. In order to investigate the trans-differentiation capacity of the cell into mature neurons, we used immunofluorescence imaging to follow NeuN protein level. The transcription level of HSP70 was shown by real-time PCR analysis. MMP-2 and -9 activities were shown by gelatin Zymography. According to data from MTT and BrdU incorporation assay, 70 mM glucose reduced cell viability and proliferation rate as compared to control (5 mM glucose) and cells treated with 40 mM glucose (P Cell exposure to 70 mM glucose had potential to induced apoptosis after 72 h (P SH-SY5Y cells to detrimental effects of high glucose condition during trans-differentiation into mature neuron-like cells. Real-time PCR analysis confirmed the expression of HSP70 in cells under high content glucose levels, demonstrating the possible cell compensatory response to an insulting condition (p control vs 70 mM group  cells being exposed to 70 mM glucose. High glucose condition could abrogate the dynamics of neural progenitor cells. The intracellular level of HSP70 was proportional to cell damage in high glucose condition. © 2018 Wiley Periodicals, Inc.

  6. High Glucose Inhibits Neural Stem Cell Differentiation Through Oxidative Stress and Endoplasmic Reticulum Stress.

    Science.gov (United States)

    Chen, Xi; Shen, Wei-Bin; Yang, Penghua; Dong, Daoyin; Sun, Winny; Yang, Peixin

    2018-06-01

    Maternal diabetes induces neural tube defects by suppressing neurogenesis in the developing neuroepithelium. Our recent study further revealed that high glucose inhibited embryonic stem cell differentiation into neural lineage cells. However, the mechanism whereby high glucose suppresses neural differentiation is unclear. To investigate whether high glucose-induced oxidative stress and endoplasmic reticulum (ER) stress lead to the inhibition of neural differentiation, the effect of high glucose on neural stem cell (the C17.2 cell line) differentiation was examined. Neural stem cells were cultured in normal glucose (5 mM) or high glucose (25 mM) differentiation medium for 3, 5, and 7 days. High glucose suppressed neural stem cell differentiation by significantly decreasing the expression of the neuron marker Tuj1 and the glial cell marker GFAP and the numbers of Tuj1 + and GFAP + cells. The antioxidant enzyme superoxide dismutase mimetic Tempol reversed high glucose-decreased Tuj1 and GFAP expression and restored the numbers of neurons and glial cells differentiated from neural stem cells. Hydrogen peroxide treatment imitated the inhibitory effect of high glucose on neural stem cell differentiation. Both high glucose and hydrogen peroxide triggered ER stress, whereas Tempol blocked high glucose-induced ER stress. The ER stress inhibitor, 4-phenylbutyrate, abolished the inhibition of high glucose or hydrogen peroxide on neural stem cell differentiation. Thus, oxidative stress and its resultant ER stress mediate the inhibitory effect of high glucose on neural stem cell differentiation.

  7. N-Acetyl-Cysteine Alleviates Gut Dysbiosis and Glucose Metabolic Disorder in High-Fat Diet-Induced Mice.

    Science.gov (United States)

    Zheng, Junping; Yuan, Xubing; Zhang, Chen; Jia, Peiyuan; Jiao, Siming; Zhao, Xiaoming; Yin, Heng; Du, Yuguang; Liu, Hongtao

    2018-05-30

    N-acetyl cysteine (NAC), an anti-oxidative reagent for clinical diseases, shows potential application to diabetes and other metabolic diseases. However, it is unknown how NAC modulates the gut microbiota of mice with metabolic syndrome. In present study, we aim to demonstrate the preventive effect of NAC on intestinal dysbiosis and glucose metabolic disorder. C57BL/6J mice were fed with normal chow diet (NCD), NCD plus NAC, high-fat diet (HFD) or HFD plus NAC for five months. After the treatment, the glucose level, circulating endotoxin and metabolism-related key proteins were determined. The fecal samples were analyzed by 16S rRNA sequencing. A novel analysis was carried out to predict the functional changes of gut microbiota. In addition, Spearman's correlation between metabolic biomarkers and bacterial abundance was also assayed. The results show that NAC treatment significantly reversed the glucose intolerance, fasting glucose level, body weight and plasma endotoxin in HFD-fed mice. Further, NAC upregulated the levels of Occludin protein and mucin glycoproteins in proximal colons of HFD-treated mice. Noticeably, NAC promoted the growth of beneficial bacteria such as Akkermansia, Bifidobacterium, Lactobacillus and Allobaculum, and hampered the population of diabetes-related genera including Desulfovibrio and Blautia. Also, NAC may influence the metabolic pathways of intestinal bacteria including lipopolysaccharide biosynthesis, oxidative stress and bacterial motility. Finally, the modified gut microbiota showed close association with the metabolic changes of the NAC treated HFD-fed mice. In summary, NAC may be a potential drug to prevent glucose metabolic disturbance by reshaping the structure of gut microbiota. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. EFFECT OF HIGH-INTENSITY EXERCISE ON ENDOTHELIAL FUNCTION IN PATIENTS WITH T2DM

    Directory of Open Access Journals (Sweden)

    Carlos Alberto da Silva

    2016-04-01

    Full Text Available Introduction: Diabetes mellitus is the most common metabolic disease worldwide. Endothelial dysfunction characteristic of these patients is one of the major risk factors for atherosclerosis. Early diagnosis of endothelial dysfunction is essential for the treatment especially of non-invasive manner, such as flow mediated dilation. Physical exercise is capable of generating beneficial adaptations may improve endothelial function. Objective: Identify the effect of physical exercise, using the clinical technique of ultrasound in the assessment of the endothelial function of patients with metabolic syndrome or type 2 diabetes mellitus. Methods: Thirty-one patients with type 2 diabetes mellitus or metabolic syndrome were studied, with a mean age (± SD of 58±6 years, randomized into three groups. The training was performed for 50 minutes, four times a week. Before and after six weeks of training, subjects performed the endurance test and a study of the endothelial function of the brachial artery by high-resolution ultrasound. Results: After hyperemia, the percentage of arterial diameter was significantly higher for the high-intensity group (HI before = 2.52±2.85mm and after = 31.81±12.21mm; LI before = 3.23±3.52mm and after = 20.61±7.76mm; controls before = 3.56±2.33mm and after = 2.43±2.14mm; p<0.05. Conclusions: The high-intensity aerobic training improved the vasodilatation response-dependent endothelium, recorded by ultrasound, in patients with metabolic syndrome and type 2 diabetes.

  9. Vasodilatory effect and endothelial integrity in papaverine- and milrinone-treated human radial arteries.

    Science.gov (United States)

    Rudzinski, P; Wegrzyn, P; Lis, G J; Piatek, J; Konstanty-Kalandyk, J; Nosalski, R; Mikolajczyk, T; Jasinska, M; Pyka-Fosciak, G; Guzik, T; Litwin, J A; Korbut, R; Sadowski, J

    2013-02-01

    Prevention of the vasospasm is an important aspect of coronary artery bypass grafting (CABG) with the use of radial artery (RA) as the conduit. We compared the effect of two phosphodiesterase inhibitors papaverine and milrinone on vasodilation and endothelial integrity of human RA segments harvested from 20 CABG patients. Vasodilatory effect of the drugs were assessed by organ bath technique in RA rings precontracted with KCl and phenylephrine. Endothelial integrity was evaluated by CD34 immunofluorescence in frozen sections. Vasorelaxation induced by papaverine was significantly greater as compared to that induced by milrinone (90.47% ± 10.16% vs. 78.98% ± 19.56%, pmilrinone in the preservation of endothelial integrity (75.3% ± 12.9% vs. 51.8% ± 18.0%, pmilrinone for prevention of vasospasm in radial artery conduits used for CABG.

  10. High glucose-mediated oxidative stress impairs cell migration.

    Directory of Open Access Journals (Sweden)

    Marcelo L Lamers

    Full Text Available Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we evaluate the hypothesis that high glucose concentrations inhibit cell migration. Using CHO.K1 cells, NIH-3T3 fibroblasts, mouse embryonic fibroblasts and primary skin fibroblasts from control and diabetic rats cultured in 5 mM D-glucose (low glucose, LG, 25 mM D-glucose (high glucose, HG or 25 mM L-glucose medium (osmotic control--OC, we analyzed the migration speed, protrusion stability, cell polarity, adhesion maturation and the activity of the small Rho GTPase Rac1. We also analyzed the effects of reactive oxygen species by incubating cells with the antioxidant N-Acetyl-Cysteine (NAC. We observed that HG conditions inhibited cell migration when compared to LG or OC. This inhibition resulted from impaired cell polarity, protrusion destabilization and inhibition of adhesion maturation. Conversely, Rac1 activity, which promotes protrusion and blocks adhesion maturation, was increased in HG conditions, thus providing a mechanistic basis for the HG phenotype. Most of the HG effects were partially or completely rescued by treatment with NAC. These findings demonstrate that HG impairs cell migration due to an increase in oxidative stress that causes polarity loss, deficient adhesion and protrusion. These alterations arise, in large part, from increased Rac1 activity and may contribute to the poor wound healing observed in diabetic patients.

  11. Functional and Biochemical Endothelial Profiling In Vivo in a Murine Model of Endothelial Dysfunction; Comparison of Effects of 1-Methylnicotinamide and Angiotensin-converting Enzyme Inhibitor

    Science.gov (United States)

    Bar, Anna; Olkowicz, Mariola; Tyrankiewicz, Urszula; Kus, Edyta; Jasinski, Krzysztof; Smolenski, Ryszard T.; Skorka, Tomasz; Chlopicki, Stefan

    2017-01-01

    Although it is known that 1-methylnicotinamide (MNA) displays vasoprotective activity in mice, as yet the effect of MNA on endothelial function has not been demonstrated in vivo. Here, using magnetic resonance imaging (MRI) we profile the effects of MNA on endothelial phenotype in mice with atherosclerosis (ApoE/LDLR-/-) in vivo, in comparison to angiotensin (Ang) -converting enzyme (ACE) inhibitor (perindopril), with known vasoprotective activity. On a biochemical level, we analyzed whether MNA- or perindopril-induced improvement in endothelial function results in changes in ACE/Ang II-ACE2/Ang-(1–7) balance, and L-arginine/asymmetric dimethylarginine (ADMA) ratio. Endothelial function and permeability were evaluated in the brachiocephalic artery (BCA) in 4-month-old ApoE/LDLR-/- mice that were non-treated or treated for 1 month or 2 months with either MNA (100 mg/kg/day) or perindopril (10 mg/kg/day). The 3D IntraGate®FLASH sequence was used for evaluation of BCA volume changes following acetylcholine (Ach) administration, and for relaxation time (T1) mapping around BCA to assess endothelial permeability using an intravascular contrast agent. Activity of ACE/Ang II and ACE2/Ang-(1–7) pathways as well as metabolites of L-arginine/ADMA pathway were measured using liquid chromatography/mass spectrometry-based methods. In non-treated 6-month-old ApoE/LDLR-/- mice, Ach induced a vasoconstriction in BCA that amounted to –7.2%. 2-month treatment with either MNA or perindopril resulted in the reversal of impaired Ach-induced response to vasodilatation (4.5 and 5.5%, respectively) and a decrease in endothelial permeability (by about 60% for MNA-, as well as perindopril-treated mice). Improvement of endothelial function by MNA and perindopril was in both cases associated with the activation of ACE2/Ang-(1–7) and the inhibition of ACE/Ang II axes as evidenced by an approximately twofold increase in Ang-(1–9) and Ang-(1–7) and a proportional decrease in Ang II

  12. Benfotiamine increases glucose oxidation and downregulates NADPH oxidase 4 expression in cultured human myotubes exposed to both normal and high glucose concentrations.

    Science.gov (United States)

    Fraser, D A; Hessvik, N P; Nikolić, N; Aas, V; Hanssen, K F; Bøhn, S K; Thoresen, G H; Rustan, A C

    2012-07-01

    The aim of the present work was to study the effects of benfotiamine (S-benzoylthiamine O-monophosphate) on glucose and lipid metabolism and gene expression in differentiated human skeletal muscle cells (myotubes) incubated for 4 days under normal (5.5 mM glucose) and hyperglycemic (20 mM glucose) conditions. Myotubes established from lean, healthy volunteers were treated with benfotiamine for 4 days. Glucose and lipid metabolism were studied with labeled precursors. Gene expression was measured using real-time polymerase chain reaction (qPCR) and microarray technology. Benfotiamine significantly increased glucose oxidation under normoglycemic (35 and 49% increase at 100 and 200 μM benfotiamine, respectively) as well as hyperglycemic conditions (70% increase at 200 μM benfotiamine). Benfotiamine also increased glucose uptake. In comparison, thiamine (200 μM) increased overall glucose metabolism but did not change glucose oxidation. In contrast to glucose, mitochondrial lipid oxidation and overall lipid metabolism were unchanged by benfotiamine. The expression of NADPH oxidase 4 (NOX4) was significantly downregulated by benfotiamine treatment under both normo- and hyperglycemic conditions. Gene set enrichment analysis (GSEA) showed that befotiamine increased peroxisomal lipid oxidation and organelle (mitochondrial) membrane function. In conclusion, benfotiamine increases mitochondrial glucose oxidation in myotubes and downregulates NOX4 expression. These findings may be of relevance to type 2 diabetes where reversal of reduced glucose oxidation and mitochondrial capacity is a desirable goal.

  13. Atorvastatin affects negatively respiratory function of isolated endothelial mitochondria.

    Science.gov (United States)

    Broniarek, Izabela; Jarmuszkiewicz, Wieslawa

    2018-01-01

    The purpose of this research was to elucidate the direct effects of two popular blood cholesterol-lowering drugs used to treat cardiovascular diseases, atorvastatin and pravastatin, on respiratory function, membrane potential, and reactive oxygen species formation in mitochondria isolated from human umbilical vein endothelial cells (EA.hy926 cell line). Hydrophilic pravastatin did not significantly affect endothelial mitochondria function. In contrast, hydrophobic calcium-containing atorvastatin induced a loss of outer mitochondrial membrane integrity, an increase in hydrogen peroxide formation, and reductions in maximal (phosphorylating or uncoupled) respiratory rate, membrane potential and oxidative phosphorylation efficiency. The atorvastatin-induced changes indicate an impairment of mitochondrial function at the level of ATP synthesis and at the level of the respiratory chain, likely at complex I and complex III. The atorvastatin action on endothelial mitochondria was highly dependent on calcium ions and led to a disturbance in mitochondrial calcium homeostasis. Uptake of calcium ions included in atorvastatin molecule induced mitochondrial uncoupling that enhanced the inhibition of the mitochondrial respiratory chain by atorvastatin. Our results indicate that hydrophobic calcium-containing atorvastatin, widely used as anti-atherosclerotic agent, has a direct negative action on isolated endothelial mitochondria. Copyright © 2017. Published by Elsevier Inc.

  14. A free-choice high-fat high-sugar diet induces glucose intolerance and insulin unresponsiveness to a glucose load not explained by obesity

    NARCIS (Netherlands)

    La Fleur, S. E.; Luijendijk, M. C. M.; van Rozen, A. J.; Kalsbeek, A.; Adan, R. A. H.

    2011-01-01

    Objectives: In diet-induced obesity, it is not clear whether impaired glucose metabolism is caused directly by the diet, or indirectly via obesity. This study examined the effects of different free-choice, high-caloric, obesity-inducing diets on glucose metabolism. In these free-choice diets,

  15. The effects of anti-obesity intervention with orlistat and sibutramine on microvascular endothelial function.

    Science.gov (United States)

    Al-Tahami, Belqes Abdullah Mohammad; Ismail, Ab Aziz Al-Safi; Bee, Yvonne Tee Get; Awang, Siti Azima; Salha Wan Abdul Rani, Wan Rimei; Sanip, Zulkefli; Rasool, Aida Hanum Ghulam

    2015-01-01

    Obesity is associated with impaired microvascular endothelial function. We aimed to determine the effects of orlistat and sibutramine treatment on microvascular endothelial function, anthropometric and lipid profile, blood pressure (BP), and heart rate (HR). 76 subjects were recruited and randomized to receive orlistat 120 mg three times daily or sibutramine 10 mg daily for 9 months. Baseline weight, BMI, BP, HR and lipid profile were taken. Microvascular endothelial function was assessed using laser Doppler fluximetry and iontophoresis process. Maximum change (max), percent change (% change) and peak flux (peak) in perfusion to acetylcholine (ACh) and sodium nitroprusside (SNP) iontophoresis were used to quantify endothelium dependent and independent vasodilatations. 24 subjects in both groups completed the trial. After treatment, weight and BMI were decreased for both groups. AChmax, ACh % change and ACh peak were increased in orlistat-treated group but no difference was observed for sibutramine-treated group. BP and total cholesterol (TC) were reduced for orlistat-treated group. HR was reduced for orlistat-treated group but was increased in sibutramine-treated group. 9 months treatment with orlistat significantly improved microvascular endothelial function. This was associated with reductions in weight, BMI, BP, HR, TC and low density lipoprotein cholesterol. No effect was seen in microvascular endothelial function with sibutramine.

  16. Effect of pistachio diet on lipid parameters, endothelial function, inflammation, and oxidative status: a prospective study.

    Science.gov (United States)

    Sari, Ibrahim; Baltaci, Yasemin; Bagci, Cahit; Davutoglu, Vedat; Erel, Ozcan; Celik, Hakim; Ozer, Orhan; Aksoy, Nur; Aksoy, Mehmet

    2010-04-01

    Recent studies have suggested that nuts have favorable effects beyond lipid lowering. We aimed to investigate effect of the Antep pistachio (Pistacia vera L.) on blood glucose, lipid parameters, endothelial function, inflammation, and oxidation in healthy young men living in a controlled environment. A Mediterranean diet was administered to normolipidemic 32 healthy young men (mean age 22 y, range 21-24) for 4 wk. After 4 wk, participants continued to receive the Mediterranean diet but pistachio was added for 4 wk by replacing the monounsaturated fat content constituting approximately 20% of daily caloric intake. Fasting blood samples and brachial endothelial function measurements were performed at baseline and after each diet. Compared with the Mediterranean diet, the pistachio diet decreased glucose (Ppistachio diet significantly improved endothelium-dependent vasodilation (P=0.002, 30% relative increase), decreased serum interleukin-6, total oxidant status, lipid hydroperoxide, and malondialdehyde and increased superoxide dismutase (Ppistachio diet improved blood glucose level, endothelial function, and some indices of inflammation and oxidative status in healthy young men. These findings are in accordance with the idea that nuts, in particular pistachio nuts, have favorable effects beyond lipid lowering that deserve to be evaluated with prospective follow-up studies. Copyright 2010. Published by Elsevier Inc.

  17. Low Molecular Weight Heparin Improves Endothelial Function in Pregnant Women at High Risk of Preeclampsia.

    Science.gov (United States)

    McLaughlin, Kelsey; Baczyk, Dora; Potts, Audrey; Hladunewich, Michelle; Parker, John D; Kingdom, John C P

    2017-01-01

    Low molecular weight heparin (LMWH) has been investigated for the prevention of severe preeclampsia, although the mechanisms of action are unknown. The objective of this study was to investigate the cardiovascular effects of LMWH in pregnant women at high risk of preeclampsia. Pregnant women at high risk of preeclampsia (n=25) and low-risk pregnant controls (n=20) at 22 to 26 weeks' gestation underwent baseline cardiovascular assessments. High-risk women were then randomized to LMWH or saline placebo (30 mg IV bolus and 1 mg/kg subcutaneous dose). Cardiovascular function was assessed 1 and 3 hours post randomization. The in vitro endothelial effects of patient serum and exogenous LMWH on human umbilical venous endothelial cells were determined. High-risk women demonstrated a reduced cardiac output, high resistance hemodynamic profile with impaired radial artery flow-mediated dilation compared with controls. LMWH increased flow-mediated dilation in high-risk women 3 hours after randomization compared with baseline and increased plasma levels of placental growth factor, soluble fms-like tyrosine kinase-1, and myeloperoxidase. Serum from high-risk women impaired endothelial cell angiogenesis and increased PlGF-1 and PlGF-2 transcription compared with serum from low-risk controls. Coexposure of high-risk serum with LMWH improved the in vitro angiogenic response such that it was equivalent to that of low-risk serum and promoted placental growth factor secretion. LMWH improves maternal endothelial function in pregnant women at high risk of developing preeclampsia, possibly mediated through increased placental growth factor bioavailability. © 2016 American Heart Association, Inc.

  18. High-intensity Interval training enhances mobilization/functionality of endothelial progenitor cells and depressed shedding of vascular endothelial cells undergoing hypoxia.

    Science.gov (United States)

    Tsai, Hsing-Hua; Lin, Chin-Pu; Lin, Yi-Hui; Hsu, Chih-Chin; Wang, Jong-Shyan

    2016-12-01

    Exercise training improves endothelium-dependent vasodilation, whereas hypoxic stress causes vascular endothelial dysfunction. Monocyte-derived endothelial progenitor cells (Mon-EPCs) contribute to vascular repair process by differentiating into endothelial cells. This study investigates how high-intensity interval (HIT) and moderate-intensity continuous (MCT) exercise training affect circulating Mon-EPC levels and EPC functionality under hypoxic condition. Sixty healthy sedentary males were randomized to engage in either HIT (3-min intervals at 40 and 80 % VO 2max for five repetitions, n = 20) or MCT (sustained 60 % VO 2max , n = 20) for 30 min/day, 5 days/week for 6 weeks, or to a control group (CTL) that did not received exercise intervention (n = 20). Mon-EPC characteristics and EPC functionality under hypoxic exercise (HE, 100 W under 12 % O 2 ) were determined before and after HIT, MCT, and CTL. The results demonstrated that after the intervention, the HIT group exhibited larger improvements in VO 2peak , estimated peak cardiac output (Q C ), and estimated peak perfusions of frontal cerebral lobe (Q FC ) and vastus lateralis (Q VL ) than the MCT group. Furthermore, HIT (a) increased circulating CD14 ++ /CD16 - /CD34 + /KDR + (Mon-1 EPC) and CD14 ++ /CD16 + /CD34 + /KDR + (Mon-2 EPC) cell counts, (b) promoted the migration and tube formation of EPCs, (c) diminished the shedding of endothelial (CD34 - /KDR + /phosphatidylserine + ) cells, and (d) elevated plasma nitrite plus nitrate, stromal cell-derived factor-1, matrix metalloproteinase-9, and vascular endothelial growth factor-A concentrations at rest or following HE, compared to those of MCT. In addition, Mon-1 and -2 EPC counts were directly related to VO 2peak and estimated peak Q C , Q FC , and Q VL . HIT is superior to MCT for improving hemodynamic adaptation and Mon-EPC production. Moreover, HIT effectively enhances EPC functionality and suppresses endothelial injury undergoing hypoxia.

  19. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... can often lower your blood glucose level by exercising. However, if your blood glucose is above 240 ... ketones. If you have ketones, do not exercise. Exercising when ketones are present may make your blood ...

  20. Hyperglycemia (High Blood Glucose)

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    Full Text Available ... Complications DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & Care Blood Glucose ... glucose) Dawn Phenomenon Checking for Ketones Tight Diabetes Control donate en -- A Future Without Diabetes - a-future- ...

  1. Osteocalcin protects pancreatic beta cell function and survival under high glucose conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kover, Karen, E-mail: kkover@cmh.edu [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States); Yan, Yun; Tong, Pei Ying; Watkins, Dara; Li, Xiaoyu [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States); Tasch, James; Hager, Melissa [Kansas City University Medical Biosciences, Kansas City, MO (United States); Clements, Mark; Moore, Wayne V. [Division of Endocrine/Diabetes, Children' s Mercy Hospital & Clinics, Kansas City, MO 64108 (United States); University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108 (United States)

    2015-06-19

    Diabetes is characterized by progressive beta cell dysfunction and loss due in part to oxidative stress that occurs from gluco/lipotoxicity. Treatments that directly protect beta cell function and survival in the diabetic milieu are of particular interest. A growing body of evidence suggests that osteocalcin, an abundant non-collagenous protein of bone, supports beta cell function and proliferation. Based on previous gene expression data by microarray, we hypothesized that osteocalcin protects beta cells from glucose-induced oxidative stress. To test our hypothesis we cultured isolated rat islets and INS-1E cells in the presence of normal, high, or high glucose ± osteocalcin for up to 72 h. Oxidative stress and viability/mitochondrial function were measured by H{sub 2}O{sub 2} assay and Alamar Blue assay, respectively. Caspase 3/7 activity was also measured as a marker of apoptosis. A functional test, glucose stimulated insulin release, was conducted and expression of genes/protein was measured by qRT-PCR/western blot/ELISA. Osteocalcin treatment significantly reduced high glucose-induced H{sub 2}O{sub 2} levels while maintaining viability/mitochondrial function. Osteocalcin also significantly improved glucose stimulated insulin secretion and insulin content in rat islets after 48 h of high glucose exposure compared to untreated islets. As expected sustained high glucose down-regulated gene/protein expression of INS1 and BCL2 while increasing TXNIP expression. Interestingly, osteocalcin treatment reversed the effects of high glucose on gene/protein expression. We conclude that osteocalcin can protect beta cells from the negative effects of glucose-induced oxidative stress, in part, by reducing TXNIP expression, thereby preserving beta cell function and survival. - Highlights: • Osteocalcin reduces glucose-induced oxidative stress in beta cells. • Osteocalcin preserves beta cell function and survival under stress conditions. • Osteocalcin reduces glucose

  2. Osteocalcin protects pancreatic beta cell function and survival under high glucose conditions

    International Nuclear Information System (INIS)

    Kover, Karen; Yan, Yun; Tong, Pei Ying; Watkins, Dara; Li, Xiaoyu; Tasch, James; Hager, Melissa; Clements, Mark; Moore, Wayne V.

    2015-01-01

    Diabetes is characterized by progressive beta cell dysfunction and loss due in part to oxidative stress that occurs from gluco/lipotoxicity. Treatments that directly protect beta cell function and survival in the diabetic milieu are of particular interest. A growing body of evidence suggests that osteocalcin, an abundant non-collagenous protein of bone, supports beta cell function and proliferation. Based on previous gene expression data by microarray, we hypothesized that osteocalcin protects beta cells from glucose-induced oxidative stress. To test our hypothesis we cultured isolated rat islets and INS-1E cells in the presence of normal, high, or high glucose ± osteocalcin for up to 72 h. Oxidative stress and viability/mitochondrial function were measured by H 2 O 2 assay and Alamar Blue assay, respectively. Caspase 3/7 activity was also measured as a marker of apoptosis. A functional test, glucose stimulated insulin release, was conducted and expression of genes/protein was measured by qRT-PCR/western blot/ELISA. Osteocalcin treatment significantly reduced high glucose-induced H 2 O 2 levels while maintaining viability/mitochondrial function. Osteocalcin also significantly improved glucose stimulated insulin secretion and insulin content in rat islets after 48 h of high glucose exposure compared to untreated islets. As expected sustained high glucose down-regulated gene/protein expression of INS1 and BCL2 while increasing TXNIP expression. Interestingly, osteocalcin treatment reversed the effects of high glucose on gene/protein expression. We conclude that osteocalcin can protect beta cells from the negative effects of glucose-induced oxidative stress, in part, by reducing TXNIP expression, thereby preserving beta cell function and survival. - Highlights: • Osteocalcin reduces glucose-induced oxidative stress in beta cells. • Osteocalcin preserves beta cell function and survival under stress conditions. • Osteocalcin reduces glucose-induced TXNIP

  3. Polycomb repressive complex 2 regulates MiR-200b in retinal endothelial cells: potential relevance in diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Michael Anthony Ruiz

    Full Text Available Glucose-induced augmented vascular endothelial growth factor (VEGF production is a key event in diabetic retinopathy. We have previously demonstrated that downregulation of miR-200b increases VEGF, mediating structural and functional changes in the retina in diabetes. However, mechanisms regulating miR-200b in diabetes are not known. Histone methyltransferase complex, Polycomb Repressive Complex 2 (PRC2, has been shown to repress miRNAs in neoplastic process. We hypothesized that, in diabetes, PRC2 represses miR-200b through its histone H3 lysine-27 trimethylation mark. We show that human retinal microvascular endothelial cells exposed to high levels of glucose regulate miR-200b repression through histone methylation and that inhibition of PRC2 increases miR-200b while reducing VEGF. Furthermore, retinal tissue from animal models of diabetes showed increased expression of major PRC2 components, demonstrating in vivo relevance. This research established a repressive relationship between PRC2 and miR-200b, providing evidence of a novel mechanism of miRNA regulation through histone methylation.

  4. Differential effects of low and high dose folic acid on endothelial dysfunction in a murine model of mild hyperhomocysteinaemia.

    Science.gov (United States)

    Clarke, Zoe L; Moat, Stuart J; Miller, Alastair L; Randall, Michael D; Lewis, Malcolm J; Lang, Derek

    2006-12-03

    The exact mechanism(s) by which hyperhomocysteinaemia promotes vascular disease remains unclear. Moreover, recent evidence suggests that the beneficial effect of folic acid on endothelial function is independent of homocysteine-lowering. In the present study the effect of a low (400 microg/70 kg/day) and high (5 mg/70 kg/day) dose folic acid supplement on endothelium-dependent relaxation in the isolated perfused mesenteric bed of heterozygous cystathionine beta-synthase deficient mice was investigated. Elevated total plasma homocysteine and impaired relaxation responses to methacholine were observed in heterozygous mice. In the presence of N(G)-nitro-L-arginine methyl ester relaxation responses in wild-type tissues were reduced, but in heterozygous tissues were abolished. Clotrimazole and 18alpha-glycyrrhetinic acid, both inhibitors of non-nitric oxide/non-prostanoid-induced endothelium-dependent relaxation, reduced responses to methacholine in wild-type but not heterozygous tissues. The combination of N(G)-nitro-L-arginine methyl ester and either clotrimazole or 18alpha-glycyrrhetinic acid completely inhibited relaxation responses in wild-type tissues. Both low and high dose folic acid increased plasma folate, reduced total plasma homocysteine and reversed endothelial dysfunction in heterozygous mice. A greater increase in plasma folate in the high dose group was accompanied by a more significant effect on endothelial function. In the presence of N(G)-nitro-L-arginine methyl ester, a significant residual relaxation response was evident in tissues from low and high dose folic acid treated heterozygous mice. These data suggest that the impaired mesenteric relaxation in heterozygous mice is largely due to loss of the non-nitric oxide/non-prostanoid component. While low dose folic acid may restore this response in a homocysteine-dependent manner, the higher dose has an additional effect on nitric oxide-mediated relaxation that would appear to be independent of

  5. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... by Mail Close www.diabetes.org > Living With Diabetes > Treatment and Care > Blood Glucose Testing Share: Print Page ... and-how-tos, . In this section Living With Diabetes Treatment and Care Blood Glucose Testing Checking Your Blood ...

  6. Integration of a highly ordered gold nanowires array with glucose oxidase for ultra-sensitive glucose detection

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Jiewu [NanoScience and Sensor Technology Research Group, School of Applied Sciences and Engineering, Monash University, Gippsland Campus, Churchill 3842, VIC Australia (Australia); Laboratory of Functional Nanomaterials and Devices, School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, Anhui (China); Adeloju, Samuel B., E-mail: sam.adeloju@monash.edu [NanoScience and Sensor Technology Research Group, School of Applied Sciences and Engineering, Monash University, Gippsland Campus, Churchill 3842, VIC Australia (Australia); Wu, Yucheng, E-mail: ycwu@hfut.edu.cn [Laboratory of Functional Nanomaterials and Devices, School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, Anhui (China)

    2014-01-27

    Graphical abstract: -- Highlights: •Successfully synthesised highly-ordered gold nanowires array with an AAO template. •Fabricated an ultra-sensitive glucose nanobiosensor with the gold nanowires array. •Achieved sensitivity as high as 379.0 μA cm{sup −2} mM{sup −1} and detection limit as low as 50 nM. •Achieved excellent anti-interference with aid of Nafion membrane towards UA and AA. •Enabled successful detection and quantification of glucose in human blood serum. -- Abstract: A highly sensitive amperometric nanobiosensor has been developed by integration of glucose oxidase (GO{sub x}) with a gold nanowires array (AuNWA) by cross-linking with a mixture of glutaraldehyde (GLA) and bovine serum albumin (BSA). An initial investigation of the morphology of the synthesized AuNWA by field emission scanning electron microscopy (FESEM) and field emission transmission electron microscopy (FETEM) revealed that the nanowires array was highly ordered with rough surface, and the electrochemical features of the AuNWA with/without modification were also investigated. The integrated AuNWA–BSA–GLA–GO{sub x} nanobiosensor with Nafion membrane gave a very high sensitivity of 298.2 μA cm{sup −2} mM{sup −1} for amperometric detection of glucose, while also achieving a low detection limit of 0.1 μM, and a wide linear range of 5–6000 μM. Furthermore, the nanobiosensor exhibited excellent anti-interference ability towards uric acid (UA) and ascorbic acid (AA) with the aid of Nafion membrane, and the results obtained for the analysis of human blood serum indicated that the device is capable of glucose detection in real samples.

  7. Effects of Everyday Life Events on Glucose, Insulin, and Glucagon Dynamics in Continuous Subcutaneous Insulin Infusion–Treated Type 1 Diabetes: Collection of Clinical Data for Glucose Modeling

    DEFF Research Database (Denmark)

    Schmidt, Signe; Finan, Daniel Aaron; Duun-Henriksen, Anne Katrine

    2012-01-01

    metabolism, we designed and conducted a clinical study.Methods: Patients with insulin pump–treated T1D were recruited to perform everyday life events on two separate days. During the study, patients wore their insulin pumps and, in addition, a continuous glucose monitor and an activity monitor to estimate...

  8. Accuracy of Handheld Blood Glucose Meters at High Altitude

    NARCIS (Netherlands)

    de Mol, Pieter; Krabbe, Hans G.; de Vries, Suzanna T.; Fokkert, Marion J.; Dikkeschei, Bert D.; Rienks, Rienk; Bilo, Karin M.; Bilo, Henk J. G.

    2010-01-01

    Background: Due to increasing numbers of people with diabetes taking part in extreme sports (e. g., high-altitude trekking), reliable handheld blood glucose meters (BGMs) are necessary. Accurate blood glucose measurement under extreme conditions is paramount for safe recreation at altitude. Prior

  9. Pre-exercise blood glucose affects glycemic variation of aerobic exercise in patients with type 2 diabetes treated with continuous subcutaneous insulin infusion.

    Science.gov (United States)

    Hu, Yun; Zhang, Dan-Feng; Dai, Lu; Li, Zheng; Li, Hui-Qin; Li, Feng-Fei; Liu, Bing-Li; Sun, Xiao-Juan; Ye, Lei; He, Ke; Ma, Jian-Hua

    2018-05-03

    Considering the insulin sensitivity may increase by exercise particularly in patients with type 2 diabetes (T2D), glycemic variation during exercise needs to be studied when the patients are treated with insulin. This study aimed to explore the influence factors of the efficacy and safety of aerobic exercise in patients with T2D treated with Continuous Subcutaneous Insulin Infusion (CSII). A total of 267 patients with T2D, treated with CSII, were included. Glycemic variations were assessed by continuous glucose monitoring (CGM). Patients were asked to complete 30 min aerobic exercise for at least one time during CGM. The patients were divided into effective and ineffective group by incremental glucose area under curve from 0 to 60 min after exercise (AUC 0-60 min ). The patients completed a total of 776 times of aerobic exercises. Blood glucose decreased fastest in the first 60 min of exercise. Pre-exercise blood glucose (PEBG) was negatively correlated with AUC 0-60 min (standardized β = -0.386, P AUC of blood glucose ≤ 4.4 mmol/L (standardized β = -0.078, P = 0.034), and was significantly higher in effective group than in ineffective group (P AUC 0-60 min during post-dinner was significantly higher than that during pre-lunch, post-lunch and pre-dinner (P  16.7 mmol/L. Post-dinner exercise decreases the blood glucose better than other periods of the day. ChiCTR-ONC-17010400, www.chictr.org.cn. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Oral salmon calcitonin protects against impaired fasting glycemia, glucose intolerance, and obesity induced by high-fat diet and ovariectomy in rats.

    Science.gov (United States)

    Feigh, Michael; Andreassen, Kim V; Hjuler, Sara T; Nielsen, Rasmus H; Christiansen, Claus; Henriksen, Kim; Karsdal, Morten A

    2013-07-01

    Oral salmon calcitonin (sCT) has demonstrated clinical efficacy in treating osteoporosis in postmenopausal women. The postmenopausal state is also associated with obesity-related insulin resistance (IR) and type 2 diabetes. The aim of this study was to investigate the preventive effects of oral sCT on energy and glucose homeostasis in high-fat diet (HFD)- and ovariectomy (OVX)-induced obese rats. Furthermore, the weight-regulatory and gluco-regulatory effects of short-term oral sCT intervention on HFD-induced obese rats were explored. For prevention, female rats exposed to HFD with or without OVX were treated with oral sCT for 5 weeks. As intervention, HFD-induced obese male rats were treated with oral sCT for 4 days. Body weight, food intake, and plasma glucose, insulin, and leptin levels were measured, and the clinical homeostasis model assessment for insulin resistance (HOMA-IR) index was calculated. In addition, oral glucose tolerance was evaluated in the systemic and portal circulations. For prevention, oral sCT reduced body weight by ∼16% to 19% (P fasting glycemia (P obesity. Furthermore, oral sCT significantly reduced the incremental area under the curve for plasma glucose and insulin by ∼40% and ∼70%, respectively, during glucose tolerance testing. As intervention in HFD-induced obese rats, oral sCT reduced body weight, fasting glycemia, and insulinemia in conjunction with HOMA-IR (P obese rats, indicating the clinical usefulness of oral sCT in postmenopausal obesity-related IR and type 2 diabetes.

  11. Proinflammatory Stimulation of Toll-Like Receptor 9 with High Dose CpG ODN 1826 Impairs Endothelial Regeneration and Promotes Atherosclerosis in Mice.

    Directory of Open Access Journals (Sweden)

    Alexander O Krogmann

    Full Text Available Toll-like receptors (TLR of the innate immune system have been closely linked with the development of atherosclerotic lesions. TLR9 is activated by unmethylated CpG motifs within ssDNA, but also by CpG motifs in nucleic acids released during vascular apoptosis and necrosis. The role of TLR9 in vascular disease remains controversial and we sought to investigate the effects of a proinflammatory TLR9 stimulation in mice.TLR9-stimulation with high dose CpG ODN at concentrations between 6.25 nM to 30 nM induced a significant proinflammatory cytokine response in mice. This was associated with impaired reendothelialization upon acute denudation of the carotid and increased numbers of circulating endothelial microparticles, as a marker for amplified endothelial damage. Chronic TLR9 agonism in apolipoprotein E-deficient (ApoE-/- mice fed a cholesterol-rich diet increased aortic production of reactive oxygen species, the number of circulating endothelial microparticles, circulating sca-1/flk-1 positive cells, and most importantly augmented atherosclerotic plaque formation when compared to vehicle treated animals. Importantly, high concentrations of CpG ODN are required for these proatherogenic effects.Systemic stimulation of TLR9 with high dose CpG ODN impaired reendothelialization upon acute vascular injury and increased atherosclerotic plaque development in ApoE-/- mice. Further studies are necessary to fully decipher the contradictory finding of TLR9 agonism in vascular biology.

  12. Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus.

    Science.gov (United States)

    Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

    2009-10-30

    The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

  13. The negative influence of high-glucose ambience on neurogenesis in developing quail embryos.

    Directory of Open Access Journals (Sweden)

    Yao Chen

    Full Text Available Gestational diabetes is defined as glucose intolerance during pregnancy and it is presented as high blood glucose levels during the onset pregnancy. This condition has an adverse impact on fetal development but the mechanism involved is still not fully understood. In this study, we investigated the effects of high glucose on the developing quail embryo, especially its impact on the development of the nervous system. We established that high glucose altered the central nervous system mophologically, such that neural tube defects (NTDs developed. In addition, we found that high glucose impaired nerve differentiation at dorsal root ganglia and in the developing limb buds, as revealed by neurofilament (NF immunofluorescent staining. The dorsal root ganglia are normally derived from neural crest cells (NCCs, so we examine the delamination of NCCs from dorsal side of the neural tube. We established that high glucose was detrimental to the NCCs, in vivo and in vitro. High glucose also negatively affected neural differentiation by reducing the number and length of neurites emanating from neurons in culture. We established that high glucose exposure caused an increase in reactive oxidative species (ROS generation by primary cultured neurons. We hypothesized that excess ROS was the factor responsible for impairing neuron development and differentiation. We provided evidence for our hypothesis by showing that the addition of vitamin C (a powerful antioxidant could rescue the damaging effects of high glucose on cultured neurons.

  14. Effect of High Fat and High Sugar Diet on Glucose Tolerance, Insulin Response to Glucose Load and Insulin Sensitivity in Rats

    OpenAIRE

    岡﨑, 悟

    1987-01-01

    To investigate the precipitating effects of the westernized diet on diabetes mellitus, glucose tolerance and insulin response to oral glucose load (1.5g/kg body weight) and insulin sensitivity to exogenous insulin (0.2U/kg) were studied in rats fed an experimental diet for 8 weeks. Four experimental diets were used : low fat-no sugar diet (energy ratio of 10% fat, 70% starch, a model of the traditional Japanese diet), high fat-high sugar diet (40% fat, 20% starch, 20% sugar, a model of the we...

  15. Combination of nitric oxide stimulation with high-dose 18F-FDG promotes apoptosis and enhances radiation therapy of endothelial cells

    International Nuclear Information System (INIS)

    Paik, Jin-Young; Park, Jin-Won; Jung, Kyung-Ho; Lee, Eun Jeong; Lee, Kyung-Han

    2012-01-01

    Introduction: High-dose 18 F-FDG can provide targeted nuclear therapy of cancer. Endothelial cell injury is a key determinant of tumor response to radiotherapy. Here, we tested the hypothesis that activation of endothelial cell glycolytic metabolism with nitric oxide can enhance the therapeutic effect of high-dose 18 F-FDG. Methods: Calf pulmonary artery endothelial (CPAE) cells were treated with graded doses of 18 F-FDG. Glycolysis was stimulated by 24 h of exposure to the nitric oxide donor, sodium nitroprusside (SNP). Cell viability was assessed by MTT and clonogenic assays. Apoptosis was evaluated by ELISA of cytosolic DNA fragments and Western blots of cleaved caspase-3. Results: SNP stimulation (0.1 and 1 mM) augmented CPAE cell 18 F-FDG uptake to 2.6- and 4.6-fold of controls without adverse effects. Treatment with 333 μCi/ml 18 F-FDG alone reduced viable cell number to 35.4% of controls by Day 3. Combining 0.1 mM SNP stimulation significantly enhanced the killing effect, reducing cell numbers to 19.2% and 39.2% of controls by 333 and 167 μCi/ml of 18 F-FDG, respectively. 18 F-FDG also suppressed clonogenic survival to 80.8% and 43.2% of controls by 83 and 167 μCi/ml, which was again intensified by SNP to 59.7% and 21.1% of controls. The cytotoxic effect of 18 F-FDG was attributed to induction of apoptosis as shown by increased cytosolic fragmented DNA and cleaved caspase-3 levels (26.4% and 30.7% increases by 167 μCi/ml). Combining SNP stimulation significantly increased both of these levels to 1.8-fold of control cells. Conclusion: High-dose 18 F-FDG combined with nitric oxide-stimulated glycolysis is an effective method to inhibit endothelial cell survival and promote apoptosis. These results suggest a potential role of this strategy for targeted radiotherapy of angiogenic vasculature.

  16. The endothelial cell receptor GRP78 is required for mucormycosis pathogenesis in diabetic mice

    Science.gov (United States)

    Liu, Mingfu; Spellberg, Brad; Phan, Quynh T.; Fu, Yue; Fu, Yong; Lee, Amy S.; Edwards, John E.; Filler, Scott G.; Ibrahim, Ashraf S.

    2010-01-01

    Mucormycosis is a fungal infection of the sinuses, brain, or lungs that causes a mortality rate of at least 50% despite first-line therapy. Because angioinvasion is a hallmark of mucormycosis infections, we sought to define the endothelial cell receptor(s) for fungi of the order Mucorales (the fungi that cause mucormycosis). Furthermore, since patients with elevated available serum iron, including those with diabetic ketoacidosis (DKA), are uniquely susceptible to mucormycosis, we sought to define the role of iron and glucose in regulating the expression of such a receptor. Here, we have identified glucose-regulated protein 78 (GRP78) as what we believe to be a novel host receptor that mediates invasion and damage of human endothelial cells by Rhizopus oryzae, the most common etiologic species of Mucorales, but not Candida albicans or Aspergillus fumigatus. Elevated concentrations of glucose and iron, consistent with those seen during DKA, enhanced GRP78 expression and the resulting R. oryzae invasion and damage of endothelial cells in a receptor-dependent manner. Mice with DKA, which have enhanced susceptibility to mucormycosis, exhibited increased expression of GRP78 in sinus, lungs, and brain compared with normal mice. Finally, GRP78-specific immune serum protected mice with DKA from mucormycosis. These results suggest a unique susceptibility of patients with DKA to mucormycosis and provide a foundation for the development of new therapeutic interventions for these deadly infections. PMID:20484814

  17. Physalis minima Leaves Extract Induces Re-Endothelialization in Deoxycorticosterone Acetate-Salt-Induced Endothelial Dysfunction in Rats

    Directory of Open Access Journals (Sweden)

    Dian Nugrahenny

    2018-02-01

    Full Text Available The administration of deoxy-corticosterone acetate (DOCA-salt can induce oxidative stress leading to decrease the bioavailability of nitric oxide (NO, increase senescence of circulating endothelial progenitor cells (EPCs, thus contributing to endothelial dysfunction. This study was aimed to investigate the effects of Physalis minima L. leaves extract on serum NO levels, circulating EPCs number, and histopathology of tail artery endothelial cells in DOCA-salt-induced endothelial dysfunction in rats. Twenty-five male Wistar rats were randomly divided into five groups: rats without any treatment (normal, rats treated with DOCA (10 mg/kgBW s.c. twice weekly and given 0.9% NaCl to drink ad libitum for 6 weeks, and DOCA-salt-induced rats orally supplemented with P. minima leaves extract at doses of 500, 1500, or 2500 mg/kgBW for 4 weeks. Serum NO levels were measured by colorimetry. The number of circulating EPCs (CD34+/CD133+ cells was determined by flow cytometry. The tail artery sections were histologically processed with hematoxylin-eosin staining. DOCA-salt-induced rats showed significantly (p<0.05 decrease in serum NO levels and circulating EPCs number compared to the normal. There was also more detached tail artery endothelial cells in DOCA-salt-induced rats. P. minima leaves extract at a dose of 500 mg/kgBW significantly (p<0.05 increased serum NO level and circulating EPCs number, and also induced an optimal re-endothelialization in DOCA-salt-induced rats. P. minima leave extract dose-dependently increases NO bioavailability contributing to enhanced EPCs mobilization, thereby promoting re-endothelialization in DOCA-salt-induced endothelial dysfunction in rats.

  18. Role of beta-adrenoceptors in memory consolidation: beta3-adrenoceptors act on glucose uptake and beta2-adrenoceptors on glycogenolysis.

    Science.gov (United States)

    Gibbs, Marie E; Hutchinson, Dana S; Summers, Roger J

    2008-09-01

    Noradrenaline, acting via beta(2)- and beta(3)-adrenoceptors (AR), enhances memory formation in single trial-discriminated avoidance learning in day-old chicks by mechanisms involving changes in metabolism of glucose and/or glycogen. Earlier studies of memory consolidation in chicks implicated beta(3)- rather than beta(2)-ARs in enhancement of memory consolidation by glucose, but did not elucidate whether stimulation of glucose uptake or of glycolysis was responsible. This study examines the role of glucose transport in memory formation using central injection of the nonselective facilitative glucose transporter (GLUT) inhibitor cytochalasin B, the endothelial/astrocytic GLUT-1 inhibitor phloretin and the Na(+)/energy-dependent endothelial glucose transporter (SGLT) inhibitor phlorizin. Cytochalasin B inhibited memory when injected into the mesopallium (avian cortex) either close to or between 25 and 45 min after training, whereas phloretin and phlorizin only inhibited memory at 30 min. This suggested that astrocytic/endothelial (GLUT-1) transport is critical at the time of consolidation, whereas a different transporter, probably the neuronal glucose transporter (GLUT-3), is important at the time of training. Inhibition of glucose transport by cytochalasin B, phloretin, or phlorizin also interfered with beta(3)-AR-mediated memory enhancement 20 min posttraining, whereas inhibition of glycogenolysis interfered with beta(2)-AR agonist enhancement of memory. We conclude that in astrocytes (1) activities of both GLUT-1 and SGLT are essential for memory consolidation 30 min posttraining; (2) neuronal GLUT-3 is essential at the time of training; and (3) beta(2)- and beta(3)-ARs consolidate memory by different mechanisms; beta(3)-ARs stimulate central glucose transport, whereas beta(2)-ARs stimulate central glycogenolysis.

  19. Continuous Glucose Monitoring in the Cardiac ICU: Current Use and Future Directions.

    Science.gov (United States)

    Scrimgeour, Laura A; Potz, Brittany A; Sellke, Frank W; Abid, M Ruhul

    2017-11-01

    Perioperative glucose control is highly important, particularly for patients undergoing cardiac surgery. Variable glucose levels before, during and after cardiac surgery lead to increased post-operative complications and patient mortality. [1] Current methods for intensive monitoring and treating hyperglycemia in the Intensive Care Unit (ICU) usually involve hourly glucose monitoring and continuous intravenous insulin infusions. With the advent of more accurate subcutaneous glucose monitoring systems, the role of improved glucose control with newer systems deserves consideration for widespread adoption.

  20. N-Methyl-D aspartate receptor-mediated effect on glucose transporter-3 levels of high glucose exposed-SH-SY5Y dopaminergic neurons.

    Science.gov (United States)

    Engin, Ayse Basak; Engin, Evren Doruk; Karakus, Resul; Aral, Arzu; Gulbahar, Ozlem; Engin, Atilla

    2017-11-01

    High glucose and insulin lead to neuronal insulin resistance. Glucose transport into the neurons is achieved by regulatory induction of surface glucose transporter-3 (GLUT3) instead of the insulin. N-methyl-D aspartate (NMDA) receptor activity increases GLUT3 expression. This study explored whether an endogenous NMDA receptor antagonist, kynurenic acid (KynA) affects the neuronal cell viability at high glucose concentrations. SH-SY5Y neuroblastoma cells were exposed to 150-250 mg/dL glucose and 40 μU/mL insulin. In KynA and N-nitro-l-arginine methyl ester (L-NAME) supplemented cultures, oxidative stress, mitochondrial metabolic activity (MTT), nitric oxide as nitrite+nitrate (NOx) and GLUT3 were determined at the end of 24 and 48-h incubation periods. Viable cells were counted by trypan blue dye. High glucose-exposed SH-SY5Y cells showed two-times more GLUT3 expression at second 24-h period. While GLUT3-stimulated glucose transport and oxidative stress was increased, total mitochondrial metabolic activity was significantly reduced. Insulin supplementation to high glucose decreased NOx synthesis and GLUT3 levels, in contrast oxidative stress increased three-fold. KynA significantly reduced oxidative stress, and increased MTT by regulating NOx production and GLUT3 expression. KynA is a noteworthy compound, as an endogenous, specific NMDA receptor antagonist; it significantly reduces oxidative stress, while increasing cell viability at high glucose and insulin concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Negative Effects of High Glucose Exposure in Human Gonadotropin-Releasing Hormone Neurons

    Directory of Open Access Journals (Sweden)

    Annamaria Morelli

    2013-01-01

    Full Text Available Metabolic disorders are often associated with male hypogonadotropic hypogonadism, suggesting that hypothalamic defects involving GnRH neurons may impair the reproductive function. Among metabolic factors hyperglycemia has been implicated in the control of the reproductive axis at central level, both in humans and in animal models. To date, little is known about the direct effects of pathological high glucose concentrations on human GnRH neurons. In this study, we investigated the high glucose effects in the human GnRH-secreting FNC-B4 cells. Gene expression profiling by qRT-PCR, confirmed that FNC-B4 cells express GnRH and several genes relevant for GnRH neuron function (KISS1R, KISS1, sex steroid and leptin receptors, FGFR1, neuropilin 2, and semaphorins, along with glucose transporters (GLUT1, GLUT3, and GLUT4. High glucose exposure (22 mM; 40 mM significantly reduced gene and protein expression of GnRH, KISS1R, KISS1, and leptin receptor, as compared to normal glucose (5 mM. Consistent with previous studies, leptin treatment significantly induced GnRH mRNA expression at 5 mM glucose, but not in the presence of high glucose concentrations. In conclusion, our findings demonstrate a deleterious direct contribution of high glucose on human GnRH neurons, thus providing new insights into pathogenic mechanisms linking metabolic disorders to reproductive dysfunctions.

  2. Protective Effects of Hesperidin (Citrus Flavonone on High Glucose Induced Oxidative Stress and Apoptosis in a Cellular Model for Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Wayne Young Liu

    2017-12-01

    Full Text Available The aim of this study was to investigate the protective effects and mechanisms of hesperidin, a plant based active flavanone found in citrus fruits, under the oxidative stress and apoptosis induced by high levels of glucose in retinal ganglial cells (RGCs. RGC-5 cells were pretreated with hesperidin (12.5, 25, or 50 μmol/L for 6 h followed by exposure to high (33.3 mmol/L d-glucose for 48 h. The 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay was adopted to evaluate cell viability. Mitochondrial function was estimated by measuring the mitochondrial membrane potential (ΔΨm. A fluorescent probe was employed to evaluate the intercellular production of reactive oxygen species (ROS. Colorimetric assay kits were used to evaluate lipid peroxidation, antioxidant enzyme activities, and protein carbonyls formation. The expression of apoptosis-related proteins and mitogen-activated protein kinase (MAPK were measured with Western blotting. Hesperidin inhibited high glucose-mediated cell loss and restored mitochondrial function including a reversion of ΔΨm loss and cytochrome c release. Treated with hesperidin, high glucose-induced increase in ROS, malondialdehyde, and protein carbonyl levels were blocked in RGC-5 cells. Hesperidin was found to elevate the activities of superoxide dismutase, catalase, glutathione peroxidase, and to recover glutathione levels. Hesperidin inhibited high glucose-induced cell apoptosis by attenuating the downregulation of caspase-9, caspase-3, and Bax/Bcl-2. Furthermore, the phosphorylation of c-Jun N-terminal kinases (JNK and p38 MAPK triggered by high glucose were attenuated in RGC-5 cells after their incubation with hesperdin. We concluded that hesperidin may protect RGC-5 cells from high glucose-induced injury since it owns the properties of antioxidant action and blocks mitochondria-mediated apoptosis.

  3. [Investigation the Inhibitory Effects of Kaempferol on Rat Renalmesangial Cells Proliferation under High Glucose Condition].

    Science.gov (United States)

    Chen, Ni; Han, Peng-Ding; Chen, Wen; Deng, Yan

    2017-07-01

    To investigate the protective effects of kaempferol on rat renal mesangial cells under high glucose condition and explore its mechanism. The HBZY-1 cells were divided into normal glucose group (5.5 mmol/L), high glucose group (25 mmol/L), 10 μmol/L kaempferol+high glucose group, and 30 μmol/L kaempferol+high glucose group. Cell proliferative ability was measured by MTT; cell cycle was analyzed by flow cytometry; mRNA and protein levels were determined by Real-time PCR and Western blot, respectively. Kaempferol had no effect on the proliferative ability of rat renal mesangial cells under normal glucose (5.5 mmol/L) condition. High glucose (25 mmol/L) enhanced the cell proliferative ability, and this effect was antagonized by kaempferol (10-30 μmol/L) treatment. High glucose reduced the cell population at G 0 /G 1 phase with an associated increase in S phase, and had no effect on G₂/M phase; and kaempferol treatment restored high glucose-induced changes in cell cycle. Kaempferol also prevented high glucose-induced increase in fibronectin and connective tissue growth factor mRNA and protein expression levels. Kaempferol also prevented high glucose-induced increase in fibronectin and connective tissue growth factor mRNA and protein expression levels. Further, high glucose caused an increase in protein level of phosphorylated p38 mitogen-activated protein kinases (p38 MAPK), which was antagonized by kaempferol treatment. Our results suggest that kaempferol exerts its protective effect on rat renal mesangial cells under high glucose condition via p38 MAPK signaling pathway.

  4. An imidazopyridine anxiolytic alters glucose tolerance in patients: a pilot investigation.

    Science.gov (United States)

    Bottaï, T; Cartault, F; Pouget, R; Blayac, J P; Petit, P

    1995-02-01

    We have recently shown that compounds with high affinity for peripheral-type benzodiazepine receptors inhibited glucose-induced insulin secretion in vitro. We therefore performed an oral glucose tolerance test in anxious inpatients treated with the imidazopyridine derivative alpidem, which has been shown to display high affinity for these binding sites. The test was performed before and after 1 week of daily administration of the drug. As compared with pretreatment values, a significant alteration of the insulin response to glucose was observed. It is suggested that daily administration of alpidem, at therapeutically effective doses for the treatment of anxiety, may alter glucose tolerance.

  5. Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

    Science.gov (United States)

    Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

    2015-07-01

    Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy.

  6. Detection of transketolase in bone marrow-derived insulin-producing cells: benfotiamine enhances insulin synthesis and glucose metabolism.

    Science.gov (United States)

    Oh, Seh-Hoon; Witek, Rafal P; Bae, Si-Hyun; Darwiche, Houda; Jung, Youngmi; Pi, Liya; Brown, Alicia; Petersen, Bryon E

    2009-01-01

    Adult bone marrow (BM)-derived insulin-producing cells (IPCs) are capable of regulating blood glucose levels in chemically induced hyperglycemic mice. Using cell transplantation therapy, fully functional BM-derived IPCs help to mediate treatment of diabetes mellitus. Here, we demonstrate the detection of the pentose phosphate pathway enzyme, transketolase (TK), in BM-derived IPCs cultured under high-glucose conditions. Benfotiamine, a known activator of TK, was not shown to affect the proliferation of insulinoma cell line, INS-1; however, when INS-1 cells were cultured with oxythiamine, an inhibitor of TK, cell proliferation was suppressed. Treatment with benfotiamine activated glucose metabolism in INS-1 cells in high-glucose culture conditions, and appeared to maximize the BM-derived IPCs ability to synthesize insulin. Benfotiamine was not shown to induce the glucose receptor Glut-2, however it was shown to activate glucokinase, the enzyme responsible for conversion of glucose to glucose-6-phosphate. Furthermore, benfotiamine-treated groups showed upregulation of the downstream glycolytic enzyme, glyceraldehyde phosphate dehydrogenase (GAPDH). However, in cells where the pentose phosphate pathway was blocked by oxythiamine treatment, there was a clear downregulation of Glut-2, glucokinase, insulin, and GAPDH. When benfotiamine was used to treat mice transplanted with BM-derived IPCs transplanted, their glucose level was brought to a normal range. The glucose challenge of normal mice treated with benfotiamine lead to rapidly normalized blood glucose levels. These results indicate that benfotiamine activates glucose metabolism and insulin synthesis to prevent glucose toxicity caused by high concentrations of blood glucose in diabetes mellitus.

  7. Detection of Transketolase in Bone Marrow—Derived Insulin-Producing Cells: Benfotiamine Enhances Insulin Synthesis and Glucose Metabolism

    Science.gov (United States)

    Witek, Rafal P.; Bae, Si-Hyun; Darwiche, Houda; Jung, Youngmi; Pi, Liya; Brown, Alicia; Petersen, Bryon E.

    2009-01-01

    Adult bone marrow (BM)-derived insulin-producing cells (IPCs) are capable of regulating blood glucose levels in chemically induced hyperglycemic mice. Using cell transplantation therapy, fully functional BM-derived IPCs help to mediate treatment of diabetes mellitus. Here, we demonstrate the detection of the pentose phosphate pathway enzyme, transketolase (TK), in BM-derived IPCs cultured under high-glucose conditions. Benfotiamine, a known activator of TK, was not shown to affect the proliferation of insulinoma cell line, INS-1; however, when INS-1 cells were cultured with oxythiamine, an inhibitor of TK, cell proliferation was suppressed. Treatment with benfotiamine activated glucose metabolism in INS-1 cells in high-glucose culture conditions, and appeared to maximize the BM-derived IPCs ability to synthesize insulin. Benfotiamine was not shown to induce the glucose receptor Glut-2, however it was shown to activate glucokinase, the enzyme responsible for conversion of glucose to glucose-6-phosphate. Furthermore, benfotiamine-treated groups showed upregulation of the downstream glycolytic enzyme, glyceraldehyde phosphate dehydrogenase (GAPDH). However, in cells where the pentose phosphate pathway was blocked by oxythiamine treatment, there was a clear downregulation of Glut-2, glucokinase, insulin, and GAPDH. When benfotiamine was used to treat mice transplanted with BM-derived IPCs transplanted, their glucose level was brought to a normal range. The glucose challenge of normal mice treated with benfotiamine lead to rapidly normalized blood glucose levels. These results indicate that benfotiamine activates glucose metabolism and insulin synthesis to prevent glucose toxicity caused by high concentrations of blood glucose in diabetes mellitus. PMID:18393672

  8. Simvastatin Ameliorates Matrix Stiffness-Mediated Endothelial Monolayer Disruption.

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    Marsha C Lampi

    Full Text Available Arterial stiffening accompanies both aging and atherosclerosis, and age-related stiffening of the arterial intima increases RhoA activity and cell contractility contributing to increased endothelium permeability. Notably, statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase inhibitors whose pleiotropic effects include disrupting small GTPase activity; therefore, we hypothesized the statin simvastatin could be used to attenuate RhoA activity and inhibit the deleterious effects of increased age-related matrix stiffness on endothelial barrier function. Using polyacrylamide gels with stiffnesses of 2.5, 5, and 10 kPa to mimic the physiological stiffness of young and aged arteries, endothelial cells were grown to confluence and treated with simvastatin. Our data indicate that RhoA and phosphorylated myosin light chain activity increase with matrix stiffness but are attenuated when treated with the statin. Increases in cell contractility, cell-cell junction size, and indirect measurements of intercellular tension that increase with matrix stiffness, and are correlated with matrix stiffness-dependent increases in monolayer permeability, also decrease with statin treatment. Furthermore, we report that simvastatin increases activated Rac1 levels that contribute to endothelial barrier enhancing cytoskeletal reorganization. Simvastatin, which is prescribed clinically due to its ability to lower cholesterol, alters the endothelial cell response to increased matrix stiffness to restore endothelial monolayer barrier function, and therefore, presents a possible therapeutic intervention to prevent atherogenesis initiated by age-related arterial stiffening.

  9. On-chip highly sensitive saliva glucose sensing using multilayer films composed of single-walled carbon nanotubes, gold nanoparticles, and glucose oxidase

    Directory of Open Access Journals (Sweden)

    Wenjun Zhang

    2015-06-01

    Full Text Available It is very important for human health to rapidly and accurately detect glucose levels in biological environments, especially for diabetes mellitus. We proposed a simple, highly sensitive, accurate, convenient, low-cost, and disposable glucose biosensor on a single chip. A working (sensor electrode, a counter electrode, and a reference electrode are integrated on a single chip through micro-fabrication. The working electrode is functionalized through a layer-by-layer (LBL assembly of single-walled carbon nanotubes (SWNTs and multilayer films composed of chitosan (CS, gold nanoparticles (GNp, and glucose oxidase (GOx to obtain high sensitivity and accuracy. The glucose sensor has following features: (1 direct electron transfer between GOx and the electrode surface; (2 on-a-chip; (3 glucose detection down to 0.1 mg/dL (5.6 μM; (4 good sensing linearity over 0.017–0.81 mM; (5 high sensitivity (61.4 μA/mM-cm2 with a small reactive area (8 mm2; (6 fast response; (7 high reproducibility and repeatability; (8 reliable and accurate saliva glucose detection. Thus, this disposable biosensor will be an alternative for real time tracking of glucose levels from body fluids, e.g. saliva, in a noninvasive, pain-free, accurate, and continuous way. In addition to being used as a disposable glucose biosensor, it also provides a suitable platform for on-chip electrochemical sensing for other chemical agents and biomolecules.

  10. Temporal metabolomic responses of cultured HepG2 liver cells to high fructose and high glucose exposures.

    Science.gov (United States)

    Meissen, John K; Hirahatake, Kristin M; Adams, Sean H; Fiehn, Oliver

    2015-06-01

    High fructose consumption has been implicated with deleterious effects on human health, including hyperlipidemia elicited through de novo lipogenesis. However, more global effects of fructose on cellular metabolism have not been elucidated. In order to explore the metabolic impact of fructose-containing nutrients, we applied both GC-TOF and HILIC-QTOF mass spectrometry metabolomic strategies using extracts from cultured HepG2 cells exposed to fructose, glucose, or fructose + glucose. Cellular responses were analyzed in a time-dependent manner, incubated in media containing 5.5 mM glucose + 5.0 mM fructose in comparison to controls incubated in media containing either 5.5 mM glucose or 10.5 mM glucose. Mass spectrometry identified 156 unique known metabolites and a large number of unknown compounds, which revealed metabolite changes due to both utilization of fructose and high-carbohydrate loads independent of hexose structure. Fructose was shown to be partially converted to sorbitol, and generated higher levels of fructose-1-phosphate as a precursor for glycolytic intermediates. Differentially regulated ratios of 3-phosphoglycerate to serine pathway intermediates in high fructose media indicated a diversion of carbon backbones away from energy metabolism. Additionally, high fructose conditions changed levels of complex lipids toward phosphatidylethanolamines. Patterns of acylcarnitines in response to high hexose exposure (10.5 mM glucose or glucose/fructose combination) suggested a reduction in mitochondrial beta-oxidation.

  11. Effect of Berberine on PPARα/NO Activation in High Glucose- and Insulin-Induced Cardiomyocyte Hypertrophy

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    Mingfeng Wang

    2013-01-01

    Full Text Available Rhizoma coptidis, the root of Coptis chinensis Franch, has been used in China as a folk medicine in the treatment of diabetes for thousands of years. Berberine, one of the active ingredients of Rhizoma coptidis, has been reported to improve symptoms of diabetes and to treat experimental cardiac hypertrophy, respectively. The objective of this study was to evaluate the potential effect of berberine on cardiomyocyte hypertrophy in diabetes and its possible influence on peroxisome proliferator-activated receptor-α (PPARα/nitric oxide (NO signaling pathway. The cardiomyocyte hypertrophy induced by high glucose (25.5 mmol/L and insulin (0.1 μmol/L (HGI was characterized in rat primary cardiomyocyte by measuring the cell surface area, protein content, and atrial natriuretic factor mRNA expression level. Protein and mRNA expression were measured by western blot and real-time RT-PCR, respectively. The enzymatic activity of NO synthase (NOS was measured using a spectrophotometric assay, and NO concentration was measured using the Griess assay. HGI significantly induced cardiomyocyte hypertrophy and decreased the expression of PPARα and endothelial NOS at the mRNA and protein levels, which occurred in parallel with declining NOS activity and NO concentration. The effect of HGI was inhibited by berberine (0.1 to 100 μmol/L, fenofibrate (0.3 μmol/L, or L-arginine (100 μmol/L. MK886 (0.3 μmol/L, a selective PPARα antagonist, could abolish the effects of berberine and fenofibrate. NG-nitro-L-arginine-methyl ester (100 μmol/L, a NOS inhibitor, could block the effects of L-arginine, but only partially blocked the effects of berberine. These results suggest that berberine can blunt HGI-induced cardiomyocyte hypertrophy in vitro, through the activation of the PPARα/NO signaling pathway.

  12. OGG1 Involvement in High Glucose-Mediated Enhancement of Bupivacaine-Induced Oxidative DNA Damage in SH-SY5Y Cells

    Science.gov (United States)

    Liu, Zhong-Jie; Zhao, Wei; Zhang, Qing-Guo; Li, Le; Lai, Lu-Ying; Jiang, Shan; Xu, Shi-Yuan

    2015-01-01

    Hyperglycemia can inhibit expression of the 8-oxoG-DNA glycosylase (OGG1) which is one of the key repair enzymes for DNA oxidative damage. The effect of hyperglycemia on OGG1 expression in response to local anesthetics-induced DNA damage is unknown. This study was designed to determine whether high glucose inhibits OGG1 expression and aggravates bupivacaine-induced DNA damage via reactive oxygen species (ROS). SH-SY5Y cells were cultured with or without 50 mM glucose for 8 days before they were treated with 1.5 mM bupivacaine for 24 h. OGG1 expression was measured by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. ROS was estimated using the redox-sensitive fluorescent dye DCFH-DA. DNA damage was investigated with immunostaining for 8-oxodG and comet assays. OGG1 expression was inhibited in cells exposed to high glucose with concomitant increase in ROS production and more severe DNA damage as compared to control culture conditions, and these changes were further exacerbated by bupivacaine. Treatment with the antioxidant N-acetyl-L-cysteine (NAC) prevented high glucose and bupivacaine mediated increase in ROS production and restored functional expression of OGG1, which lead to attenuated high glucose-mediated exacerbation of bupivacaine neurotoxicity. Our findings indicate that subjects with diabetes may experience more detrimental effects following bupivacaine use. PMID:26161242

  13. OGG1 Involvement in High Glucose-Mediated Enhancement of Bupivacaine-Induced Oxidative DNA Damage in SH-SY5Y Cells

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    Zhong-Jie Liu

    2015-01-01

    Full Text Available Hyperglycemia can inhibit expression of the 8-oxoG-DNA glycosylase (OGG1 which is one of the key repair enzymes for DNA oxidative damage. The effect of hyperglycemia on OGG1 expression in response to local anesthetics-induced DNA damage is unknown. This study was designed to determine whether high glucose inhibits OGG1 expression and aggravates bupivacaine-induced DNA damage via reactive oxygen species (ROS. SH-SY5Y cells were cultured with or without 50 mM glucose for 8 days before they were treated with 1.5 mM bupivacaine for 24 h. OGG1 expression was measured by quantitative real-time polymerase chain reaction (qRT-PCR and western blot. ROS was estimated using the redox-sensitive fluorescent dye DCFH-DA. DNA damage was investigated with immunostaining for 8-oxodG and comet assays. OGG1 expression was inhibited in cells exposed to high glucose with concomitant increase in ROS production and more severe DNA damage as compared to control culture conditions, and these changes were further exacerbated by bupivacaine. Treatment with the antioxidant N-acetyl-L-cysteine (NAC prevented high glucose and bupivacaine mediated increase in ROS production and restored functional expression of OGG1, which lead to attenuated high glucose-mediated exacerbation of bupivacaine neurotoxicity. Our findings indicate that subjects with diabetes may experience more detrimental effects following bupivacaine use.

  14. Glucose and Lipid Dysmetabolism in a Rat Model of Prediabetes Induced by a High-Sucrose Diet

    Science.gov (United States)

    Burgeiro, Ana; Cerqueira, Manuela G.; Varela-Rodríguez, Bárbara M.; Nunes, Sara; Neto, Paula; Pereira, Frederico C.; Reis, Flávio; Carvalho, Eugénia

    2017-01-01

    Glucotoxicity and lipotoxicity are key features of type 2 diabetes mellitus, but their molecular nature during the early stages of the disease remains to be elucidated. We aimed to characterize glucose and lipid metabolism in insulin-target organs (liver, skeletal muscle, and white adipose tissue) in a rat model treated with a high-sucrose (HSu) diet. Two groups of 16-week-old male Wistar rats underwent a 9-week protocol: HSu diet (n = 10)—received 35% of sucrose in drinking water; Control (n = 12)—received vehicle (water). Body weight, food, and beverage consumption were monitored and glucose, insulin, and lipid profiles were measured. Serum and liver triglyceride concentrations, as well as the expression of genes and proteins involved in lipid biosynthesis were assessed. The insulin-stimulated glucose uptake and isoproterenol-stimulated lipolysis were also measured in freshly isolated adipocytes. Even in the absence of obesity, this rat model already presented the main features of prediabetes, with fasting normoglycemia but reduced glucose tolerance, postprandial hyperglycemia, compensatory hyperinsulinemia, as well as decreased insulin sensitivity (resistance) and hypertriglyceridemia. In addition, impaired hepatic function, including altered gluconeogenic and lipogenic pathways, as well as increased expression of acetyl-coenzyme A carboxylase 1 and fatty acid synthase in the liver, were observed, suggesting that liver glucose and lipid dysmetabolism may play a major role at this stage of the disease. PMID:28635632

  15. Insulin binding and glucose transport in adipocytes of acarbose-treated Zucker lean and obese rats.

    Science.gov (United States)

    Vasselli, J R; Flory, T; Fried, S K

    1987-01-01

    The intestinal glucosidase inhibitor acarbose was administered as a dietary admix (30 mg/100 g chow diet) to male Zucker obese and lean rats. After 15 weeks, epidiymal fat pads were removed and adipocytes isolated by collagenase digestion. Equilibrium binding of A-14 tyrosine 125I-insulin, and transport of U-14C-glucose was determined was adipocytes incubated for 50 min at 37 degrees C in 0-16000 pM insulin. Insulin binding/cell was enhanced two-fold in lean (P less than 0.01) and obese (n.s.) drug groups. In drug-treated leans, increased sensitivity of glucose transport to submaximally stimulating concentrations of insulin was observed (P less than 0.02). For both genotypes, acarbose mildly decreased insulin levels and body weight gain, although adipocyte size was unaffected. Results indicate that enhanced insulin binding accompanies metabolic improvements induced by acarbose in lean Zucker rats.

  16. Effects of flaxseed oil on anti-oxidative system and membrane deformation of human peripheral blood erythrocytes in high glucose level.

    Science.gov (United States)

    Yang, Wei; Fu, Juan; Yu, Miao; Huang, Qingde; Wang, Di; Xu, Jiqu; Deng, Qianchun; Yao, Ping; Huang, Fenghong; Liu, Liegang

    2012-07-08

    The erythrocyte membrane lesion is a serious diabetic complication. A number of studies suggested that n-3 fatty acid could reduce lipid peroxidation and elevate α- or γ-tocopherol contents in membrane of erythrocytes. However, evidence regarding the protective effects of flaxseed oil, a natural product rich in n-3 fatty acid, on lipid peroxidation, antioxidative capacity and membrane deformation of erythrocytes exposed to high glucose is limited. Human peripheral blood erythrocytes were isolated and treated with 50 mM glucose to mimic hyperglycemia in the absence or presence of three different doses of flaxseed oil (50, 100 or 200 μM) in the culture medium for 24 h. The malondialdehyde (MDA) and L-glutathione (GSH) were measured by HPLC and LC/MS respectively. The phospholipids symmetry and membrane fatty acid composition of human erythrocytes were detected by flow cytometry and gas chromatograph (GC). The morphology of human erythrocyte was illuminated by ultra scanning electron microscopy. Flaxseed oil attenuated hyperglycemia-induced increase of MDA and decrease of GSH in human erythrocytes. Human erythrocytes treated with flaxseed oil contained higher C22:5 and C22:6 than those in the 50 mM glucose control group, indicating that flaxseed oil could reduce lipid asymmetric distribution and membrane perturbation. The ultra scanning electron microscopy and flow cytometer have also indicated that flaxseed oil could protect the membrane of human erythrocytes from deformation at high glucose level. The flaxseed oil supplementation may prevent lipid peroxidation and membrane dysfunction of human erythrocytes in hyperglycemia.

  17. Anti-diabetic potential of the essential oil of Pinus koraiensis leaves toward streptozotocin-treated mice and HIT-T15 pancreatic β cells.

    Science.gov (United States)

    Joo, Hye-Eun; Lee, Hyo-Jung; Sohn, Eun Jung; Lee, Min-Ho; Ko, Hyun-Suk; Jeong, Soo-Jin; Lee, Hyo-Jeong; Kim, Sung-Hoon

    2013-01-01

    The metabolic syndrome creates risk factors for coronary heart disease, diabetes, fatty liver, obesity and several cancers. Our group has already reported that the essential oil from leaves of Pinus koraiensis SIEB (EOPK) exerted antihyperlipidemic effects by upregulating the low-density lipoprotein receptor and inhibiting acyl-coenzyme A, cholesterol acyltransferases. We evaluated in the current study the anti-diabetic effects of EOPK on mice with streptozotocin (STZ)-induced type I diabetes and on HIT-T15 pancreatic β cells. EOPK significantly protected HIT-T15 cells from STZ-induced cytotoxicity and reduced the blood glucose level in STZ-induced diabetic mice when compared with the untreated control. EOPK consistently and significantly suppressed the α-amylase activity in a dose-dependent manner and enhanced the expression of insulin at the mRNA level in STZ-treated HIT-T15 cells, while the expression of insulin was attenuated. EOPK also significantly abrogated the population of reactive oxygen species when compared to the untreated control in STZ-treated HIT-T15 cells. Furthermore, EOPK significantly reduce nitric oxide production, suppressed the phosphorylation of endothelial nitric oxide (NO) synthase and suppressed the production of vascular endothelial growth factor (VEGF) in STZ-treated HIT-T15 cells, implying its potential application to diabetic retinopathy. Overall, our findings suggest that EOPK had hypoglycemic potential by inhibiting reactive oxygene species (ROS), endothelial NO synthase (eNOS) and VEGF in STZ-treated mice and HIT-T15 pancreatic β cells as a potent anti-diabetic agent.

  18. RhoA GTPase regulates radiation-induced alterations in endothelial cell adhesion and migration

    International Nuclear Information System (INIS)

    Rousseau, Matthieu; Gaugler, Marie-Hélène; Rodallec, Audrey; Bonnaud, Stéphanie; Paris, François; Corre, Isabelle

    2011-01-01

    Highlights: ► We explore the role of RhoA in endothelial cell response to ionizing radiation. ► RhoA is rapidly activated by single high-dose of radiation. ► Radiation leads to RhoA/ROCK-dependent actin cytoskeleton remodeling. ► Radiation-induced apoptosis does not require the RhoA/ROCK pathway. ► Radiation-induced alteration of endothelial adhesion and migration requires RhoA/ROCK. -- Abstract: Endothelial cells of the microvasculature are major target of ionizing radiation, responsible of the radiation-induced vascular early dysfunctions. Molecular signaling pathways involved in endothelial responses to ionizing radiation, despite being increasingly investigated, still need precise characterization. Small GTPase RhoA and its effector ROCK are crucial signaling molecules involved in many endothelial cellular functions. Recent studies identified implication of RhoA/ROCK in radiation-induced increase in endothelial permeability but other endothelial functions altered by radiation might also require RhoA proteins. Human microvascular endothelial cells HMEC-1, either treated with Y-27632 (inhibitor of ROCK) or invalidated for RhoA by RNA interference were exposed to 15 Gy. We showed a rapid radiation-induced activation of RhoA, leading to a deep reorganisation of actin cytoskeleton with rapid formation of stress fibers. Endothelial early apoptosis induced by ionizing radiation was not affected by Y-27632 pre-treatment or RhoA depletion. Endothelial adhesion to fibronectin and formation of focal adhesions increased in response to radiation in a RhoA/ROCK-dependent manner. Consistent with its pro-adhesive role, ionizing radiation also decreased endothelial cells migration and RhoA was required for this inhibition. These results highlight the role of RhoA GTPase in ionizing radiation-induced deregulation of essential endothelial functions linked to actin cytoskeleton.

  19. Roles of glucose in photoreceptor survival.

    Science.gov (United States)

    Chertov, Andrei O; Holzhausen, Lars; Kuok, Iok Teng; Couron, Drew; Parker, Ed; Linton, Jonathan D; Sadilek, Martin; Sweet, Ian R; Hurley, James B

    2011-10-07

    Vertebrate photoreceptor neurons have a high demand for metabolic energy, and their viability is very sensitive to genetic and environmental perturbations. We investigated the relationship between energy metabolism and cell death by evaluating the metabolic effects of glucose deprivation on mouse photoreceptors. Oxygen consumption, lactate production, ATP, NADH/NAD(+), TCA cycle intermediates, morphological changes, autophagy, and viability were evaluated. We compared retinas incubated with glucose to retinas deprived of glucose or retinas treated with a mixture of mitochondrion-specific fuels. Rapid and slow phases of cell death were identified. The rapid phase is linked to reduced mitochondrial activity, and the slower phase reflects a need for substrates for cell maintenance and repair.

  20. Frequency of diabetes, impaired fasting glucose, and glucose intolerance in high-risk groups identified by a FINDRISC survey in Puebla City, Mexico

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    Hirales-Tamez O

    2012-11-01

    Full Text Available Hector García-Alcalá, Christelle Nathalie Genestier-Tamborero, Omara Hirales-Tamez, Jorge Salinas-Palma, Elena Soto-VegaFaculty of Medicine, Universidad Popular Autónoma del Estado de Puebla, Puebla Pue, MexicoBackground: As a first step in the prevention of diabetes, the International Diabetes Federation recommends identification of persons at risk using the Finnish type 2 Diabetes Risk Assessment (FINDRISC survey. The frequency of diabetes mellitus, impaired fasting glucose, and glucose intolerance in high-risk groups identified by FINDRISC is unknown in our country. The aim of this study was to determine the frequency of diabetes mellitus, impaired fasting glucose, and glucose intolerance in higher-risk groups using a FINDRISC survey in an urban population.Methods: We used a television program to invite interested adults to fill out a survey at a television station. An oral glucose tolerance test was performed in all persons with a FINDRISC score ≥ 15 points (high-risk and very high-risk groups. Patients were classified as normal (fasting glucose < 100 mg/dL and 2-hour glucose < 140 mg/dL, or having impaired fasting glucose (fasting glucose 100–125 mg/dL and 2-hour glucose < 140 mg/dL, glucose intolerance (fasting glucose < 126 mg/dL and 2-hour glucose 140–199 mg/dL, and diabetes mellitus (fasting glucose ≥ 126 mg/dL or 2-hour glucose ≥ 200 mg/dL. We describe the frequency of each diagnostic category in this selected population according to gender and age.Results: A total of 186 patients had a score ≥ 15. The frequencies of diabetes mellitus, impaired fasting glucose, glucose intolerance, and normal glucose levels were 28.6%, 25.9%, 29.2%, and 16.2%, respectively. We found a higher frequency of diabetes mellitus and impaired fasting glucose in men than in women (33% versus 27% and 40% versus 21%, respectively and more glucose intolerance in women than in men (34% versus 16%, P < 0.05. Patients with diabetes mellitus (52.55 ± 9

  1. High environmental temperature increases glucose requirement in the developing chicken embryo.

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    Roos Molenaar

    Full Text Available Environmental conditions during the perinatal period influence metabolic and developmental processes in mammals and avian species, which could impact pre- and postnatal survival and development. The current study investigated the effect of eggshell temperature (EST on glucose metabolism in broiler chicken embryos. Broiler eggs were incubated at a high (38.9°C or normal (37.8°C EST from day 10.5 of incubation onward and were injected with a bolus of [U-(13C]glucose in the chorio-allantoic fluid at day 17.5 of incubation. After [U-(13C]glucose administration, (13C enrichment was determined in intermediate pools and end-products of glucose metabolism. Oxidation of labeled glucose occurred for approximately 3 days after injection. Glucose oxidation was higher in the high than in the normal EST treatment from day 17.6 until 17.8 of incubation. The overall recovery of (13CO2 tended to be 4.7% higher in the high than in the normal EST treatment. An increase in EST (38.9°C vs 37.8°C increased (13C enrichment in plasma lactate at day 17.8 of incubation and (13C in hepatic glycogen at day 18.8 of incubation. Furthermore, high compared to normal EST resulted in a lower yolk-free body mass at day 20.9 (-2.74 g and 21.7 (-3.81 g of incubation, a lower hepatic glycogen concentration at day 18.2 (-4.37 mg/g and 18.8 (-4.59 mg/g of incubation, and a higher plasma uric acid concentration (+2.8 mg/mL/+43% at day 21.6 of incubation. These results indicate that the glucose oxidation pattern is relatively slow, but the intensity increased consistently with an increase in developmental stage of the embryo. High environmental temperatures in the perinatal period of chicken embryos increased glucose oxidation and decreased hepatic glycogen prior to the hatching process. This may limit glucose availability for successful hatching and could impact body development, probably by increased gluconeogenesis from glucogenic amino acids to allow anaerobic glycolysis.

  2. Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus

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    Brenner Benjamin

    2009-10-01

    Full Text Available Abstract Background The function of endothelial progenitor cells (EPCs, which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD, the enzyme that neutralizes superoxide anion (O2-. Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. Methods The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. Results EPCs from diabetic patients generated more O2-, had higher NAD(PH oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Conclusion Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

  3. Highly Selective and Sensitive Self-Powered Glucose Sensor Based on Capacitor Circuit.

    Science.gov (United States)

    Slaughter, Gymama; Kulkarni, Tanmay

    2017-05-03

    Enzymatic glucose biosensors are being developed to incorporate nanoscale materials with the biological recognition elements to assist in the rapid and sensitive detection of glucose. Here we present a highly sensitive and selective glucose sensor based on capacitor circuit that is capable of selectively sensing glucose while simultaneously powering a small microelectronic device. Multi-walled carbon nanotubes (MWCNTs) is chemically modified with pyrroloquinoline quinone glucose dehydrogenase (PQQ-GDH) and bilirubin oxidase (BOD) at anode and cathode, respectively, in the biofuel cell arrangement. The input voltage (as low as 0.25 V) from the biofuel cell is converted to a stepped-up power and charged to the capacitor to the voltage of 1.8 V. The frequency of the charge/discharge cycle of the capacitor corresponded to the oxidation of glucose. The biofuel cell structure-based glucose sensor synergizes the advantages of both the glucose biosensor and biofuel cell. In addition, this glucose sensor favored a very high selectivity towards glucose in the presence of competing and non-competing analytes. It exhibited unprecedented sensitivity of 37.66 Hz/mM.cm 2 and a linear range of 1 to 20 mM. This innovative self-powered glucose sensor opens new doors for implementation of biofuel cells and capacitor circuits for medical diagnosis and powering therapeutic devices.

  4. Effects of Basal Insulin Analog and Metformin on Glycaemia Control and Weight as Risk Factors for Endothelial Dysfunction

    Directory of Open Access Journals (Sweden)

    Belma Aščić – Buturović

    2008-11-01

    Full Text Available Obese patients with type 2 diabetes and impaired glucose tolerance are at increased risk of development of cardiovascular diseases. Endothelial dysfunction may be a reason for development of atherosclerosis and cardiovascular diseases. Lifestyle modification, increased physical activity, weight reduction, energy restricted diet and good glycaemia control can be useful for the endothelial function improvement and may decrease the risk of cardiovascular diseases. The aim of this study was to evaluate the effects of basal insulin analog and metformin on glycaemia control and weight as risk factors of endothelial dysfunction. Total of 15 patients (9 male and 6 female with type 2 diabetes were studied. The patients were monitored over six months period. Glycated hemoglobin (HbA1c, fasting plasma glucose (FPG, postprandial plasma glucose (PPG, and body mass index (BMI were observed. Mean age of the subjects was 53,4 ± 6,27 years. Mean diabetes duration was 3,71 ± 1,89 years. At the end of the study mean body mass index decreased from 27,5 ± 1,45 kg/m2 to 25,7 ±1,22 kg/m2. In this study we included diabetic patients with fasting glycaemia over 7 mmol/ dm3, postmeal glycaemia over 7,8 mmol/dm3 and glycated hemoglobin over 7%. Prior to the study, the patients were treated with premix insulin divided in two daily doses and metformin after the lunch, which did not result in sufficient regulation of glycaemia. We started treatment with one daily insulin basal analog and three daily doses of metformin and monitored the above mentioned parameters. We advised patients to change their lifestyle, to practice energy restricted diet and to increase their daily physical activity. Insulin doses were titrated separately for each patient (0,7-1 IU/kg. Weight reduction was recorded after the study. Mean fasting glycaemia decreased from 8,6±0,49 mmol/dm3 to 7,04±0,19 mmol/dm3 (p < 0,05. Mean postmeal glycaemia decreased from 9,74 ± 0,79 mmol/dm3 to 7,6 ± 0

  5. Infantile hemangioma-derived stem cells and endothelial cells are inhibited by class 3 semaphorins

    International Nuclear Information System (INIS)

    Nakayama, Hironao; Huang, Lan; Kelly, Ryan P.; Oudenaarden, Clara R.L.; Dagher, Adelle; Hofmann, Nicole A.; Moses, Marsha A.; Bischoff, Joyce; Klagsbrun, Michael

    2015-01-01

    Class 3 semaphorins were discovered as a family of axon guidance molecules, but are now known to be involved in diverse biologic processes. In this study, we investigated the anti-angiogenic potential of SEMA3E and SEMA3F (SEMA3E&F) in infantile hemangioma (IH). IH is a common vascular tumor that involves both vasculogenesis and angiogenesis. Our lab has identified and isolated hemangioma stem cells (HemSC), glucose transporter 1 positive (GLUT1 + ) endothelial cells (designated as GLUT1 sel cells) based on anti-GLUT1 magnetic beads selection and GLUT1-negative endothelial cells (named HemEC). We have shown that these types of cells play important roles in hemangiogenesis. We report here that SEMA3E inhibited HemEC migration and proliferation while SEMA3F was able to suppress the migration and proliferation in all three types of cells. Confocal microscopy showed that stress fibers in HemEC were reduced by SEMA3E&F and that stress fibers in HemSC were decreased by SEMA3F, which led to cytoskeletal collapse and loss of cell motility in both cell types. Additionally, SEMA3E&F were able to inhibit vascular endothelial growth factor (VEGF)-induced sprouts in all three types of cells. Further, SEMA3E&F reduced the level of p-VEGFR2 and its downstream p-ERK in HemEC. These results demonstrate that SEMA3E&F inhibit IH cell proliferation and suppress the angiogenic activities of migration and sprout formation. SEMA3E&F may have therapeutic potential to treat or prevent growth of highly proliferative IH. - Highlights: • SEMA3E&F reduce actin stress fibers and induce cytoskeletal collapse in HemEC. • SEMA3E&F inhibit angiogenic activities of HemEC. • SEMA3E&F can interrupt the VEGF-A-VEGFR2-ERK signaling pathway in HemEC. • Plexin D1 and NRP2 are induced during HemSC/GLUT1 sel -to-EC differentiation

  6. Infantile hemangioma-derived stem cells and endothelial cells are inhibited by class 3 semaphorins

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Hironao [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Division of Cell Growth and Tumor Regulation, Proteo-Science Center, Ehime University, Toon, Ehime 791-0295 (Japan); Huang, Lan [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Kelly, Ryan P.; Oudenaarden, Clara R.L. [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Dagher, Adelle; Hofmann, Nicole A.; Moses, Marsha A. [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Bischoff, Joyce, E-mail: joyce.bischoff@childrens.harvard.edu [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Klagsbrun, Michael, E-mail: michael.klagsbrun@childrens.harvard.edu [Vascular Biology Program, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Surgery, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States); Department of Pathology, Boston Children' s Hospital, Harvard Medical School, Boston, MA 02115 (United States)

    2015-08-14

    Class 3 semaphorins were discovered as a family of axon guidance molecules, but are now known to be involved in diverse biologic processes. In this study, we investigated the anti-angiogenic potential of SEMA3E and SEMA3F (SEMA3E&F) in infantile hemangioma (IH). IH is a common vascular tumor that involves both vasculogenesis and angiogenesis. Our lab has identified and isolated hemangioma stem cells (HemSC), glucose transporter 1 positive (GLUT1{sup +}) endothelial cells (designated as GLUT1{sup sel} cells) based on anti-GLUT1 magnetic beads selection and GLUT1-negative endothelial cells (named HemEC). We have shown that these types of cells play important roles in hemangiogenesis. We report here that SEMA3E inhibited HemEC migration and proliferation while SEMA3F was able to suppress the migration and proliferation in all three types of cells. Confocal microscopy showed that stress fibers in HemEC were reduced by SEMA3E&F and that stress fibers in HemSC were decreased by SEMA3F, which led to cytoskeletal collapse and loss of cell motility in both cell types. Additionally, SEMA3E&F were able to inhibit vascular endothelial growth factor (VEGF)-induced sprouts in all three types of cells. Further, SEMA3E&F reduced the level of p-VEGFR2 and its downstream p-ERK in HemEC. These results demonstrate that SEMA3E&F inhibit IH cell proliferation and suppress the angiogenic activities of migration and sprout formation. SEMA3E&F may have therapeutic potential to treat or prevent growth of highly proliferative IH. - Highlights: • SEMA3E&F reduce actin stress fibers and induce cytoskeletal collapse in HemEC. • SEMA3E&F inhibit angiogenic activities of HemEC. • SEMA3E&F can interrupt the VEGF-A-VEGFR2-ERK signaling pathway in HemEC. • Plexin D1 and NRP2 are induced during HemSC/GLUT1{sup sel}-to-EC differentiation.

  7. Modeling the ischemic blood-brain barrier; the effects of oxygen-glucose deprivation (OGD) on endothelial cells in culture

    DEFF Research Database (Denmark)

    Tornabene, Erica; Helms, Hans Christian Cederberg; Berndt, Philipp

    Introduction - The blood-brain barrier (BBB) is a physical, transport and metabolic barrier which plays a key role in preventing uncontrolled exchanges between blood and brain, ensuring an optimal environment for neurons activity. This extent interface is created by the endothelial cells forming...... pathways across the barrier in ischemic and postischemic brain endothelium is important for developing new medical therapies capable to exploit the barrier changes occurring during/after ischemia to permeate in the brain and treat this devastating disease. Materials and Methods - Primary cultures...... the wall of brain capillaries. The restrictive nature of the BBB is due to the tight junctions (TJs), which seal the intercellular clefts, limiting the paracellular diffusion, efflux transporters, which extrude xenobiotics, and metabolizing enzymes, which may break down or convert molecules during...

  8. Propolis, a Constituent of Honey, Inhibits the Development of Sugar Cataracts and High-Glucose-Induced Reactive Oxygen Species in Rat Lenses

    Directory of Open Access Journals (Sweden)

    Teppei Shibata

    2016-01-01

    Full Text Available Purpose. This study investigated the effects of oral propolis on the progression of galactose-induced sugar cataracts in rats and the in vitro effects of propolis on high-glucose-induced reactive oxygen species (ROS and cell death in cultured rat lens cells (RLECs. Methods. Galactose-fed rats and RLECs cultured in high glucose (55 mM medium were treated with propolis or vehicle control. Relative lens opacity was assessed by densitometry and changes in lens morphology by histochemical analysis. Intracellular ROS levels and cell viability were measured. Results. Oral administration of propolis significantly inhibited the onset and progression of cataract in 15% and 25% of galactose-fed rats, respectively. RLECs cultured with high glucose showed a significant increase in ROS expression with reduced cell viability. Treatment of these RLECs with 5 and 50 μg/mL propolis cultured significantly reduced ROS levels and increased cell viability, indicating that the antioxidant activity of propolis protected cells against ROS-induced damage. Conclusion. Propolis significantly inhibited the onset and progression of sugar cataract in rats and mitigated high-glucose-induced ROS production and cell death. These effects may be associated with the ability of propolis to inhibit hyperglycemia-evoked oxidative or osmotic stress-induced cellular insults.

  9. Impairment of endothelial-myocardial interaction increases the susceptibility of cardiomyocytes to ischemia/reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Thorsten M Leucker

    Full Text Available Endothelial-myocardial interactions may be critically important for ischemia/reperfusion injury. Tetrahydrobiopterin (BH4 is a required cofactor for nitric oxide (NO production by endothelial NO synthase (eNOS. Hyperglycemia (HG leads to significant increases in oxidative stress, oxidizing BH4 to enzymatically incompetent dihydrobiopterin. How alterations in endothelial BH4 content impact myocardial ischemia/reperfusion injury remains elusive. The aim of this study was to examine the effect of endothelial-myocardial interaction on ischemia/reperfusion injury, with an emphasis on the role of endothelial BH4 content. Langendorff-perfused mouse hearts were treated by triton X-100 to produce endothelial dysfunction and subsequently subjected to 30 min of ischemia followed by 2 h of reperfusion. The recovery of left ventricular systolic and diastolic function during reperfusion was impaired in triton X-100 treated hearts compared with vehicle-treated hearts. Cardiomyocytes (CMs were co-cultured with endothelial cells (ECs and subsequently subjected to 2 h of hypoxia followed by 2 h of reoxygenation. Addition of ECs to CMs at a ratio of 1∶3 significantly increased NO production and decreased lactate dehydrogenase activity compared with CMs alone. This EC-derived protection was abolished by HG. The addition of 100 µM sepiapterin (a BH4 precursor or overexpression of GTP cyclohydrolase 1 (the rate-limiting enzyme for BH4 biosynthesis in ECs by gene trasfer enhanced endothelial BH4 levels, the ratio of eNOS dimer/monomer, eNOS phosphorylation, and NO production and decreased lactate dehydrogenase activity in the presence of HG. These results demonstrate that increased BH4 content in ECs by either pharmacological or genetic approaches reduces myocardial damage during hypoxia/reoxygenation in the presence of HG. Maintaining sufficient endothelial BH4 is crucial for cardioprotection against hypoxia/reoxygenation injury.

  10. Glucose kinetics at rest and during exercise in gluconeogenesis-inhibited rats

    International Nuclear Information System (INIS)

    Turcotte, L.P.

    1988-01-01

    To evaluate the role played by gluconeogenesis in blood glucose homeostasis, untrained and trained rats were injected with mercaptopicolinic acid (MPA), a known inhibitor of the gluconeogenic enzyme, phosphoenolpyruvate carboxykinase. Glucose turnover, recycling and oxidation rates were assessed by primed-continuous infusion of [U- 14 C]- and [6- 3 H] glucose at rest and during submaximal exercise at 13.4 m/min on level grade. When compared to the untrained sham-injected animals, the untrained MPA-treated animals had 22% lower and 44% higher resting blood glucose and lactate concentrations, respectively. Resting glucose turnover, calculated from [6- 3 H]glucose, was 32% lower in the MPA-treated animals than in the sham-injected animals. During exercise, turnover increased in the sham-injected animals but remained unchanged in the MPA-treated animals. MPA-treated animals had no glucose recycling at rest or during exercise. Exercise further decreased blood glucose concentration and increased blood lactate concentration in the MPA-treated animals, but MPA treatment did not change the exercise-induced increases in glucose oxidation rate, % total VCO 2 arising from glucose oxidation and metabolic clearance rate of glucose

  11. Decrease of postprandial endothelial dysfunction by spice mix added to high-fat hamburger meat in men with Type 2 diabetes mellitus.

    Science.gov (United States)

    Li, Z; Henning, S M; Zhang, Y; Rahnama, N; Zerlin, A; Thames, G; Tseng, C H; Heber, D

    2013-05-01

    Consumption of a high-fat diet has been demonstrated to promote endothelial dysfunction, possibly through an increase in lipid peroxidation and decrease in serum nitric oxide. The present study was designed to investigate whether consumption of a hamburger cooked with a polyphenol-rich spice mixture will reduce postprandial lipid oxidation and endothelial dysfunction in men with Type 2 diabetes. Twenty-two subjects consumed burgers cooked with salt only (control burger) or with salt and spice mix (spice burger) in randomized order. The postprandial concentration of urinary malondialdehyde and nitrate/nitrite as well as the peripheral arterial tonometry score were determined. Eighteen subjects completed the study. Postprandial serum glucose, insulin and triglyceride concentrations were similar in all subjects after control burger or spice burger consumption. Urine malondialdehyde excretion in mmol/g creatinine was reduced by 31% (P spice burger compared with the control burger. Two hours after consumption of the burgers, the peripheral arterial tonometry score was significantly different between control burger consumption (-9.7 ± 21.5%) and spice burger consumption (+18.0 ± 42.4%) (P = 0.025). Mean urinary nitrate/nitrite concentrations in urine collected during the 6 h after consumption of the control burger was 9.09 ± 5.7 mmol/g creatinine, but 12.37 ± 7.00 mmol/g creatinine after the spice burger (P = 0.053). Adding a spice mix to hamburger meat prior to cooking resulted in a reduction in urinary malondialdehyde, an increase in urinary nitrate/nitrite and improvement of postprandial endothelial dysfunction in men with Type 2 diabetes. Therefore, cooking a hamburger with a polyphenol-rich spice mixture may lead to potential cardiovascular benefits in patients with Type 2 diabetes mellitus. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK.

  12. Gestational diabetes, preeclampsia and cytokine release: similarities and differences in endothelial cell function.

    Science.gov (United States)

    Rao, Rashmi; Sen, Suvajit; Han, Bing; Ramadoss, Sivakumar; Chaudhuri, Gautam

    2014-01-01

    Gestational diabetes, pre-eclampsia as well as intra-uterine infection during pregnancy affects the function of the endothelium both in the mother and the fetus leading to endothelial dysfunction. Gestational diabetes is also associated with an increased incidence of pre-eclampsia and it is likely that both the hyperglycemia as well as the release of cytokines especially TNFα during hyperglycemia may play an important role in the pathogenesis of endothelial dysfunction leading to preeclampsia. Similarly, some but not all studies have suggested that infection of the mother under certain circumstances can also lead to preeclampsia as women with either a bacterial or viral infection were at a higher risk of developing preeclampsia, compared to women without infection and infection also leads to a release in TNFα. Endothelial cells exposed to either high glucose or TNFα leads to an increase in the production of H2O2 and to a decrease in endothelial cell proliferation. The cellular and molecular mechanisms involved in this phenomenon are discussed.Gestational diabetes, pre-eclampsia as well as intra-uterine infection during pregnancy has profound effects on the fetus and long term effects on the neonate. All three conditions affect the function of the endothelium both in the mother and the fetus leading to endothelial dysfunction. Gestational diabetes is also associated with an increased incidence of pre-eclampsia and it is likely that both the hyperglycemia as well as the release of cytokines especially TNFα during hyperglycemia may play an important role in the pathogenesis of endothelial dysfunction leading to preeclampsia. It has also been suggested although not universally accepted that under certain circumstances maternal infection may also predispose to pre-eclampsia. Pre-eclampsia is also associated with the release of TNFα and endothelial dysfunction. However, the cellular and molecular mechanism(s) leading to the endothelial dysfunction by either

  13. Reduced endothelial thioredoxin-interacting protein protects arteries from damage induced by metabolic stress in vivo.

    Science.gov (United States)

    Bedarida, Tatiana; Domingues, Alison; Baron, Stephanie; Ferreira, Chrystophe; Vibert, Francoise; Cottart, Charles-Henry; Paul, Jean-Louis; Escriou, Virginie; Bigey, Pascal; Gaussem, Pascale; Leguillier, Teddy; Nivet-Antoine, Valerie

    2018-06-01

    Although thioredoxin-interacting protein (TXNIP) is involved in a variety of biologic functions, the contribution of endothelial TXNIP has not been well defined. To investigate the endothelial function of TXNIP, we generated a TXNIP knockout mouse on the Cdh5-cre background (TXNIP fl/fl cdh5 cre ). Control (TXNIP fl/fl ) and TXNIP fl/fl cdh5 cre mice were fed a high protein-low carbohydrate (HP-LC) diet for 3 mo to induce metabolic stress. We found that TXNIP fl/fl and TXNIP fl/fl cdh5 cre mice on an HP-LC diet displayed impaired glucose tolerance and dyslipidemia concretizing the metabolic stress induced. We evaluated the impact of this metabolic stress on mice with reduced endothelial TXNIP expression with regard to arterial structure and function. TXNIP fl/fl cdh5 cre mice on an HP-LC diet exhibited less endothelial dysfunction than littermate mice on an HP-LC diet. These mice were protected from decreased aortic medial cell content, impaired aortic distensibility, and increased plasminogen activator inhibitor 1 secretion. This protective effect came with lower oxidative stress and lower inflammation, with a reduced NLRP3 inflammasome expression, leading to a decrease in cleaved IL-1β. We also show the major role of TXNIP in inflammation with a knockdown model, using a TXNIP-specific, small interfering RNA included in a lipoplex. These findings demonstrate a key role for endothelial TXNIP in arterial impairments induced by metabolic stress, making endothelial TXNIP a potential therapeutic target.-Bedarida, T., Domingues, A., Baron, S., Ferreira, C., Vibert, F., Cottart, C.-H., Paul, J.-L., Escriou, V., Bigey, P., Gaussem, P., Leguillier, T., Nivet-Antoine, V. Reduced endothelial thioredoxin-interacting protein protects arteries from damage induced by metabolic stress in vivo.

  14. Hyperglycemia and oxidized-LDL exert a deleterious effect on endothelial progenitor cell migration in type 2 diabetes mellitus.

    Science.gov (United States)

    Hamed, Saher; Brenner, Benjamin; Abassi, Zaid; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

    2010-09-01

    Type 2 diabetes mellitus (DM) patients with coronary artery disease (CAD) have elevated plasma oxidized-LDL (OxLDL) levels and impaired neovascularization. Hyperglycemia and hyperlipidemia impair endothelial progenitor cell (EPC) migration, and endothelial nitric oxide (NO) bioavailability and NO synthase (NOS) activity are essential for EPC migration. Stromal-derived factor-1alpha (SDF1alpha) contributes to EPC mobilization and homing by stimulating the CXC receptor-4 (CXCR4) on the EPC plasmalemma to activate the Pi3K/Akt/eNOS signaling pathway. Therefore, we investigated the effect of high glucose (HG) and OxLDL on the migration and NO bioavailability of EPCs from healthy individuals, and then correlated the findings with those of EPCs from type 2 DM patients with and without CAD. EPCs from 15 healthy and 55 patients were exposed to HG, OxLDL, or both before evaluating EPC count, migration and NO production, and expression of CXCR4 and members of Pi3K/Akt/eNOS signaling cascade. Counts, migration, CXCR4 expression, and NO production were significantly reduced in EPCs from DM and CAD patients compared with that obtained in EPCs from healthy, and were further reduced in DM patients with CAD. The expression of CXCR4 and activation of Pi3K/Akt/eNOS signaling cascade were suppressed in OxLDL- and HG-treated EPCs, and this suppression was exacerbated when EPCs were treated simultaneously with HG and OxLDL. Hyperglycemia and elevated circulating OxLDL in DM patients with CAD severely impair EPC migration. These results suggest that the underlying mechanism for this impaired EPC migration is linked to the CXCR4/Pi3K/Akt/eNOS signaling pathway. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  15. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Tercia Rodrigues [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Carvalho da Fonseca, Anna Carolina [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Nunes, Sara Santana; Oliveira da Silva, Aline [Universidade do Estado do Rio de Janeiro (UERJ), Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biologia Celular, Laboratorio de Biologia da Celula Endotelial e da Angiogenese (LabAngio), Rio de Janeiro (Brazil); Dubois, Luiz Gustavo Feijo; Faria, Jane; Kahn, Suzana Assad [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); Viana, Nathan Bessa [Universidade Federal do Rio de Janeiro, Laboratorio de Pincas Oticas, Coordenacao de Programas de Estudos Avancados, Instituto de Ciencias Biomedicas, Rio de Janeiro (Brazil); Universidade Federal do Rio de Janeiro, Instituto de Fisica, Rio de Janeiro (Brazil); Marcondes, Jorge [Universidade Federal do Rio de Janeiro, Hospital Universitario Clementino Fraga Filho, Servico de Neurocirurgia, Rio de Janeiro (Brazil); Legrand, Chantal [Institut Universitaire d' Hematologie, Universite Paris-Diderot, Paris 7, INSERM U553, Paris (France); Moura-Neto, Vivaldo [Universidade Federal do Rio de Janeiro (UFRJ), Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciencias Biomedicas, INNT/INCT/MCT, Rio de Janeiro (Brazil); and others

    2011-09-10

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  16. Tenascin-C in the extracellular matrix promotes the selection of highly proliferative and tubulogenesis-defective endothelial cells

    International Nuclear Information System (INIS)

    Alves, Tercia Rodrigues; Carvalho da Fonseca, Anna Carolina; Nunes, Sara Santana; Oliveira da Silva, Aline; Dubois, Luiz Gustavo Feijo; Faria, Jane; Kahn, Suzana Assad; Viana, Nathan Bessa; Marcondes, Jorge; Legrand, Chantal; Moura-Neto, Vivaldo

    2011-01-01

    The extracellular matrix (ECM) contains important cues for tissue homeostasis and morphogenesis. The matricellular protein tenascin-C (TN-C) is overexpressed in remodeling tissues and cancer. In the present work, we studied the effect of different ECM-which exhibited a significant diversity in their TN-C content-in endothelial survival, proliferation and tubulogenic differentiation: autologous (endothelial) ECM devoid of TN-C, but bearing large amounts of FN; fibroblast ECM, bearing both high TN-C and FN contents; and finally, glioma-derived matrices, usually poor in FN, but very rich in TN-C. HUVECs initially adhered to the immobilized matrix produced by U373 MG glioma cells, but significantly detached and died by anoikis (50 to 80%) after 24 h, as compared with cells incubated with endothelial and fibroblast matrices. Surviving endothelial cells (20 to 50%) became up to 6-fold more proliferative and formed 74-97% less tube-like structures in vitro than cells grown on non-tumoral matrices. An antibody against the EGF-like repeats of tenascin-C (TN-C) partially rescued cells from the tubulogenic defect, indicating that this molecule is responsible for the selection of highly proliferative and tubulogenic defective endothelial cells. Interestingly, by using defined substrata, in conditions that mimic glioma and normal cell ECM composition, we observed that fibronectin (FN) modulates the TN-C-induced selection of endothelial cells. Our data show that TN-C is able to modulate endothelial branching morphogenesis in vitro and, since it is prevalent in matrices of injured and tumor tissues, also suggest a role for this protein in vascular morphogenesis, in these physiological contexts.

  17. Endothelial dysfunction in normoglycaemic first-degree relatives of type 2 diabetes mellitus complicated with hyperuricaemia.

    Science.gov (United States)

    Zhang, Junxia; Xiang, Lin; Zhang, Bilin; Cheng, Yangyang

    2017-03-01

    To reveal the effect of hyperuricaemia on endothelial function in normoglycaemic first-degree relatives of type 2 diabetes mellitus. In all, 40 first-degree relatives of type 2 diabetes mellitus with hyperuricaemia, 40 first-degree relatives of type 2 diabetes mellitus with normouricaemia and 35 healthy subjects without diabetic family history were recruited in this study. Anthropometric parameters as well as blood pressure, blood lipids, fasting blood glucose, fasting insulin, C-reactive protein, tumour necrosis factor-α and interleukin-6 were measured. Insulin resistance was assessed with homoeostasis model assessment index-insulin resistance index. To assess endothelial function, high-resolution ultrasonography was used for measuring flow- and nitroglycerine-mediated brachial artery vasodilation. When compared with control, flow-mediated dilation was lower in first-degree relatives with or without hyperuricaemia (both p type 2 diabetes mellitus (β = -0.677, p type 2 diabetes mellitus complicated with hyperuricaemia.

  18. High glucose alters the expression of genes involved in proliferation and cell-fate specification of embryonic neural stem cells.

    Science.gov (United States)

    Fu, J; Tay, S S W; Ling, E A; Dheen, S T

    2006-05-01

    Maternal diabetes induces neural tube defects during embryogenesis. Since the neural tube is derived from neural stem cells (NSCs), it is hypothesised that in diabetic pregnancy neural tube defects result from altered expression of developmental control genes, leading to abnormal proliferation and cell-fate choice of NSCs. Cell viability, proliferation index and apoptosis of NSCs and differentiated cells from mice exposed to physiological or high glucose concentration medium were examined by a tetrazolium salt assay, 5-bromo-2'-deoxyuridine incorporation, terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling and immunocytochemistry. Expression of developmental genes, including sonic hedgehog (Shh), bone morphogenetic protein 4 (Bmp4), neurogenin 1/2 (Neurog1/2), achaete-scute complex-like 1 (Ascl1), oligodendrocyte transcription factor 1 (Olig1), oligodendrocyte lineage transcription factor 2 (Olig2), hairy and enhancer of split 1/5 (Hes1/5) and delta-like 1 (Dll1), was analysed by real-time RT-PCR. Proliferation index and neuronal specification in the forebrain of embryos at embryonic day 11.5 were examined histologically. High glucose decreased the proliferation of NSCs and differentiated cells. The incidence of apoptosis was increased in NSCs treated with high glucose, but not in the differentiated cells. High glucose also accelerated neuronal and glial differentiation from NSCs. The decreased proliferation index and early differentiation of neurons were evident in the telencephalon of embryos derived from diabetic mice. Exposure to high glucose altered the mRNA expression levels of Shh, Bmp4, Neurog1/2, Ascl1, Hes1, Dll1 and Olig1 in NSCs and Shh, Dll1, Neurog1/2 and Hes5 in differentiated cells. The changes in proliferation and differentiation of NSCs exposed to high glucose are associated with altered expression of genes that are involved in cell-cycle progression and cell-fate specification during neurulation. These changes may form the

  19. Vitamin D Receptor Activation Mitigates the Impact of Uremia on Endothelial Function in the 5/6 Nephrectomized Rats

    Directory of Open Access Journals (Sweden)

    J. Ruth Wu-Wong

    2010-01-01

    Full Text Available Endothelial dysfunction increases cardiovascular disease risk in chronic kidney disease (CKD. This study investigates whether VDR activation affects endothelial function in CKD. The 5/6 nephrectomized (NX rats with experimental chronic renal insufficiency were treated with or without paricalcitol, a VDR activator. Thoracic aortic rings were precontracted with phenylephrine and then treated with acetylcholine or sodium nitroprusside. Uremia significantly affected aortic relaxation (−50.0±7.4% in NX rats versus −96.2±5.3% in SHAM at 30 M acetylcholine. The endothelial-dependent relaxation was improved to –58.2±6.0%, –77.5±7.3%, and –90.5±4.0% in NX rats treated with paricalcitol at 0.021, 0.042, and 0.083 g/kg for two weeks, respectively, while paricalcitol at 0.042 g/kg did not affect blood pressure and heart rate. Parathyroid hormone (PTH suppression alone did not improve endothelial function since cinacalcet suppressed PTH without affecting endothelial-dependent vasorelaxation. N-omega-nitro-L-arginine methyl ester completely abolished the effect of paricalcitol on improving endothelial function. These results demonstrate that VDR activation improves endothelial function in CKD.

  20. Possible involvement of 12-lipoxygenase activation in glucose-deprivation/reload-treated neurons.

    Science.gov (United States)

    Nagasawa, Kazuki; Kakuda, Taichi; Higashi, Youichirou; Fujimoto, Sadaki

    2007-12-18

    The aim of this study was to clarify whether 12-lipoxygenase (12-LOX) activation was involved in reactive oxygen species (ROS) generation, extensive poly(ADP-ribose) polymerase (PARP) activation and neuronal death induced by glucose-deprivation, followed by glucose-reload (GD/R). The decrease of neuronal viability and accumulation of poly(ADP-ribose) induced by GD/R were prevented 3-aminobenzamide, a representative PARP inhibitor, demonstrating this treatment protocol caused the same oxidative stress with the previously reported one. The PARP activation, ROS generation and decrease of neuron viability induced by GD/R treatment were almost completely abolished by an extracellular zinc chelator, CaEDTA. p47(phox), a cytosolic component of NADPH oxidase was translocated the membrane fraction by GD/R, indicating its activation, but it did not generate detectable ROS. Surprisingly, pharmacological inhibition of NADPH oxidase with apocynin and AEBSF further decreased the decreased neuron viability induced by GD/R. On the other hand, AA861, a 12-LOX inhibitor, prevented ROS generation and decrease of neuron viability caused by GD/R. Interestingly, an antioxidant, N-acetyl-l-cysteine rescued the neurons from GD/R-induced oxidative stress, implying effectiveness of antioxidant administration. These findings suggested that activation of 12-LOX, but not NADPH oxidase, following to zinc release might play an important role in ROS generation and decrease of viability in GD/R-treated neurons.

  1. First step toward near-infrared continuous glucose monitoring: in vivo evaluation of antibody coupled biomaterials

    Science.gov (United States)

    Gellynck, Karolien; Kodeck, Valérie; Van De Walle, Elke; Kersemans, Ken; De Vos, Filip; Declercq, Heidi; Dubruel, Peter; Vlaminck, Lieven

    2015-01-01

    Continuous glucose monitoring (CGM) is crucial in diabetic care. Long-term CGM systems however require an accurate sensor as well as a suitable measuring environment. Since large intravenous sensors are not feasible, measuring inside the interstitial fluid is considered the best alternative. This option, unfortunately, has the drawback of a lag time with blood glucose values. A good strategy to circumvent this is to enhance tissue integration and enrich the peri-implant vasculature. Implants of different optically transparent biomaterials (poly(methyl-methacrylate) [PMMA] and poly(dimethylsiloxane) [PDMS]) – enabling glucose monitoring in the near-infrared (NIR) spectrum – were surface-treated and subsequently implanted in goats at various implantation sites for up to 3 months. The overall in vivo biocompatibility, tissue integration, and vascularization at close proximity of the surfaces of these materials were assessed. Histological screening showed similar tissue reactions independent of the implantation site. No significant inflammation reaction was observed. Tissue integration and vascularization correlated, to some extent, with the biomaterial composition. A modification strategy, in which a vascular endothelial-cadherin antibody was coupled to the biomaterials surface through a dopamine layer, showed significantly enhanced vascularization 3 months after subcutaneous implantation. Our results suggest that the developed strategy enables the creation of tissue interactive NIR transparent packaging materials, opening the possibility of continuous glucose monitoring. PMID:25304314

  2. Comparison of endothelial progenitor cells in Parkinson's disease patients treated with levodopa and levodopa/COMT inhibitor.

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    Phil Hyu Lee

    Full Text Available BACKGROUND: Levodopa treatment in Parkinson's disease (PD increases in serum homocysteine levels due to its metabolism via catechol O-methyltransferase. Endothelial progenitor cells (EPCs have the capacity to differentiate into mature endothelial cells and are markers for endothelial functions and cardiovascular risks. Along with traditional vascular risk factors, hyperhomocysteinemia is known to decrease the level of EPCs. In the present study, we hypothesized that that levodopa-induced hyperhomocysteinemia leads to a change in EPC levels. METHODOLOGY/PRINCIPAL FINDINGS: We prospectively enrolled PD patients who had been prescribed either levodopa/carbidopa (PD-L group, n = 28 or levodopa/carbidopa/COMT inhibitor (PD-LC group, n = 25 for more than 1 year. The number of circulating EPCs was measured by flow cytometry using dual staining of anti-CD34 and anti-KDR antibodies. The EPCs were divided into tertiles based on their distributions and a logistic regression analysis was used to estimate independent predictors of the highest tertile of EPCs. The number of endothelial progenitor cells was significantly decreased in PD-L patients (118±99/mL compared with either PD-LC patients (269±258/mL, p = 0.007 or controls (206±204/mL, p = 0.012. The level of homocysteine was significantly increased in PD-L patients (14.9±5.3 µmol/L compared with either PD-LC patients (11.9±3.0 µmol/L, p = 0.028 or controls (11.1±2.5 µmol/L, p = 0.012. The level of homocysteine was negatively correlated with endothelial progenitor cell levels (r = -0.252, p = 0.028 and was an independent predictor of the highest tertile of endothelial progenitor cell levels (OR; 0.749 [95% CI: 0.584-0.961]. CONCLUSIONS/SIGNIFICANCE: These data indicate that a higher consumption of EPC for restoration of endothelial damage may be associated with chronic levodopa treatment in PD patients.

  3. Endothelial function in male body builders taking anabolic androgenic steroids

    Directory of Open Access Journals (Sweden)

    H Hashemi

    2005-11-01

    Full Text Available Background: Adverse cardiovascular events have been reported in body builders taking anabolic steroids. Adverse effects of AAS on endothelial function can initiate atherosclerosis. This study evaluates endothelial function in body builders using AAS, compared with non-steroids using athletes as controls. Methods: We recruited 30 nonsmoking male body builders taking AAS, 14 in build up phase, 8 in work out phase, and 8 in post steroid phase, and 30 nonsmoking male athletes who denied ever using steroids. Serum lipids and fasting plasma glucose were measured to exclude dyslipidemia and diabetes. Brachial artery diameter was measured by ultrasound at rest, after cuff inflation, and after sublingual glyceriltrinitrate (GTN to determine flow mediated dilation (FMD, nitro mediated dilation (NMD and ratio of FMD to NMD (index of endothelial function. Result: Use of AAS was associated with higher body mass index (BMI and low density lipoprotein–cholesterol (LDL-C. Mean ratio of flow mediated dilatation after cuff deflation to post GTN dilatation of brachial artery (index of endothelial function in body builders taking AAS was significantly lower than control group (0.96(0.05 versus 1(0.08; p=0.03. After adjusting BMI, age and weight, no significant difference was seen in index of endothelial function between two groups (p=0 .21. Conclusion: Our study indicates that taking AAS in body builders doesn’t have direct effect on endothelial function. Future study with bigger sample size and measurement of AAS metabolites is recommended. Key words: endothelium, lipids, anabolic steroids, body builders

  4. Targeting renal glucose reabsorption to treat hyperglycaemia: the pleiotropic effects of SGLT2 inhibition.

    Science.gov (United States)

    Vallon, Volker; Thomson, Scott C

    2017-02-01

    also uricosuric. These pleiotropic effects of SGLT2 inhibitors are likely to have contributed to the results of the EMPA-REG OUTCOME trial in which the SGLT2 inhibitor, empagliflozin, slowed the progression of chronic kidney disease and reduced major adverse cardiovascular events in high-risk individuals with type 2 diabetes. This review discusses the role of SGLT2 in the physiology and pathophysiology of renal glucose reabsorption and outlines the unexpected logic of inhibiting SGLT2 in the diabetic kidney.

  5. Statins Prevent Dextrose-Induced Endoplasmic Reticulum Stress and Oxidative Stress in Endothelial and HepG2 Cells.

    Science.gov (United States)

    Kojanian, Hagop; Szafran-Swietlik, Anna; Onstead-Haas, Luisa M; Haas, Michael J; Mooradian, Arshag D

    Statins have favorable effects on endothelial function partly because of their capacity to reduce oxidative stress. However, antioxidant vitamins, unlike statins, are not as cardioprotective, and this paradox has been explained by failure of vitamin antioxidants to ameliorate endoplasmic reticulum (ER) stress. To determine whether statins prevent dextrose-induced ER stress in addition to their antioxidative effects, human umbilical vein endothelial cells and HepG2 hepatocytes were treated with 27.5 mM dextrose in the presence of simvastatin (lipophilic statin that is a prodrug) and pravastatin (water-soluble active drug), and oxidative stress, ER stress, and cell death were measured. Superoxide generation was measured using 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride. ER stress was measured using the placental alkaline phosphatase assay and Western blot of glucose-regulated protein 75, c-jun-N-terminal kinase, phospho-JNK, eukaryotic initiating factor 2α and phospho-eIF2α, and X-box binding protein 1 mRNA splicing. Cell viability was measured by propidium iodide staining. Superoxide anion production, ER stress, and cell death induced by 27.5 mM dextrose were inhibited by therapeutic concentrations of simvastatin and pravastatin. The salutary effects of statins on endothelial cells in reducing both ER stress and oxidative stress observed with pravastatin and the prodrug simvastatin suggest that the effects may be independent of cholesterol-lowering activity.

  6. Activation of K{sup +} channels and Na{sup +}/K{sup +} ATPase prevents aortic endothelial dysfunction in 7-day lead-treated rats

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    Fiorim, Jonaina, E-mail: nanafiorim@hotmail.com [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Ribeiro Júnior, Rogério Faustino, E-mail: faustino43@oi.com.br [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Azevedo, Bruna Fernades, E-mail: brunafernandes.azevedo@gmail.com [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Padilha, Alessandra Simão, E-mail: ale_spadilha@yahoo.com.br [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Stefanon, Ivanita, E-mail: ivanita@pq.cnpq.br [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Alonso, Maria Jesus, E-mail: mariajesus.alonso@urjc.es [Departamento de Ciencias de la Salud III, Universidad Rey Juan Carlos, Alcorcón (Spain); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Departamento de Farmacología, Universidad Autónoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPaz) (Spain); Vassallo, Dalton Valentim, E-mail: daltonv2@terra.com.br [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil)

    2012-07-01

    Seven day exposure to a low concentration of lead acetate increases nitric oxide bioavailability suggesting a putative role of K{sup +} channels affecting vascular reactivity. This could be an adaptive mechanism at the initial stages of toxicity from lead exposure due to oxidative stress. We evaluated whether lead alters the participation of K{sup +} channels and Na{sup +}/K{sup +}-ATPase (NKA) on vascular function. Wistar rats were treated with lead (1st dose 4 μg/100 g, subsequent doses 0.05 μg/100 g, im, 7 days) or vehicle. Lead treatment reduced the contractile response of aortic rings to phenylephrine (PHE) without changing the vasodilator response to acetylcholine (ACh) or sodium nitroprusside (SNP). Furthermore, this treatment increased basal O{sub 2}{sup −} production, and apocynin (0.3 μM), superoxide dismutase (150 U/mL) and catalase (1000 U/mL) reduced the response to PHE only in the treated group. Lead also increased aortic functional NKA activity evaluated by K{sup +}-induced relaxation curves. Ouabain (100 μM) plus L-NAME (100 μM), aminoguanidine (50 μM) or tetraethylammonium (TEA, 2 mM) reduced the K{sup +}-induced relaxation only in lead-treated rats. When aortic rings were precontracted with KCl (60 mM/L) or preincubated with TEA (2 mM), 4-aminopyridine (4-AP, 5 mM), iberiotoxin (IbTX, 30 nM), apamin (0.5 μM) or charybdotoxin (0.1 μM), the ACh-induced relaxation was more reduced in the lead-treated rats. Additionally, 4-AP and IbTX reduced the relaxation elicited by SNP more in the lead-treated rats. Results suggest that lead treatment promoted NKA and K{sup +} channels activation and these effects might contribute to the preservation of aortic endothelial function against oxidative stress. -- Highlights: ► Increased free radicals production ► Increased Na{sup +}/K{sup +} ATPase activity ► Promotes activation of the K{sup +} channels and reduced vascular reactivity ► These effects preserve endothelial function against oxidative

  7. Integration of a highly ordered gold nanowires array with glucose oxidase for ultra-sensitive glucose detection.

    Science.gov (United States)

    Cui, Jiewu; Adeloju, Samuel B; Wu, Yucheng

    2014-01-27

    A highly sensitive amperometric nanobiosensor has been developed by integration of glucose oxidase (GO(x)) with a gold nanowires array (AuNWA) by cross-linking with a mixture of glutaraldehyde (GLA) and bovine serum albumin (BSA). An initial investigation of the morphology of the synthesized AuNWA by field emission scanning electron microscopy (FESEM) and field emission transmission electron microscopy (FETEM) revealed that the nanowires array was highly ordered with rough surface, and the electrochemical features of the AuNWA with/without modification were also investigated. The integrated AuNWA-BSA-GLA-GO(x) nanobiosensor with Nafion membrane gave a very high sensitivity of 298.2 μA cm(-2) mM(-1) for amperometric detection of glucose, while also achieving a low detection limit of 0.1 μM, and a wide linear range of 5-6000 μM. Furthermore, the nanobiosensor exhibited excellent anti-interference ability towards uric acid (UA) and ascorbic acid (AA) with the aid of Nafion membrane, and the results obtained for the analysis of human blood serum indicated that the device is capable of glucose detection in real samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. High glucose-induced Ca2+ overload and oxidative stress contribute to apoptosis of cardiac cells through mitochondrial dependent and independent pathways.

    Science.gov (United States)

    Kumar, Sandeep; Kain, Vasundhara; Sitasawad, Sandhya L

    2012-07-01

    Cardiac cell apoptosis is the initiating factor of cardiac complications especially diabetic cardiomyopathy. Mitochondria are susceptible to the damaging effects of elevated glucose condition. Calcium overload and oxidative insult are the two mutually non-exclusive phenomena suggested to cause cardiac dysfunction. Here, we examined the effect of high-glucose induced calcium overload in calpain-1 mediated cardiac apoptosis in an in vitro setting. H9c2, rat ventricular myoblast cell line was treated with elevated glucose condition and the cellular consequences were studied. Intracellular calcium trafficking, ROS generation, calpain-1 activation and caspase-12 and caspase-9 pathway were studied using flow cytometry, confocal microscopy and Western blot analysis. High-glucose treatment resulted in increased intracellular calcium ([Ca2+]i) which was mobilized to the mitochondria. Concomitant intra-mitochondrial calcium ([Ca2+]m) increase resulted in enhanced reactive oxygen and nitrogen species generation. These events led to mitochondrial dysfunction and apoptosis. Cardiomyocyte death exhibited several classical markers of apoptosis, including activation of caspases, appearance of annexin V on the outer plasma membrane, increased population of cells with sub-G0/G1 DNA content and nuclear condensation. Key findings include elucidation of cell signaling mechanism of high-glucose induced calcium-dependent cysteine protease calpain-1 activation, which triggers non-conventional caspases as alternate mode of cell death. This information increases the understanding of cardiac cell death under hyperglycemic condition and can possibly be extended for designing new therapeutic strategies for diabetic cardiomyopathy. The novel findings of the study reveal that high glucose induces apoptosis by both mitochondria-dependent and independent pathways via concomitant rise in intracellular calcium. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Impaired blood rheology is associated with endothelial dysfunction in patients with coronary risk factors.

    Science.gov (United States)

    Yagi, Hideki; Sumino, Hiroyuki; Aoki, Tomoyuki; Tsunekawa, Katsuhiko; Araki, Osamu; Kimura, Takao; Nara, Makoto; Ogiwara, Takayuki; Murakami, Masami

    2016-01-01

    To investigate the relationship between blood rheology and endothelial function in patients with coronary risk factors, brachial arterial flow-mediated vasodilatation (FMD), an index of endothelial function and blood passage time (BPT), an index of blood rheology, and fasting blood cell count, glucose metabolism, and plasma fibrinogen, lipid, C-reactive protein, and whole blood viscosity levels were measured in 95 patients with coronary risk factors and 37 healthy controls. Brachial arterial FMD after reactive hyperemia was assessed by ultrasonography. BPT was assessed using the microchannel method. In healthy controls, BPT significantly correlated with FMD (r = - 0.325, p index (BMI; r = 0.530, p measurement of blood rheology using the microchannel method may be useful in evaluating brachial arterial endothelial function as a marker of atherosclerosis in these patients.

  10. Ascorbic acid attenuates endothelial permeability triggered by cell-free hemoglobin.

    Science.gov (United States)

    Kuck, Jamie L; Bastarache, Julie A; Shaver, Ciara M; Fessel, Joshua P; Dikalov, Sergey I; May, James M; Ware, Lorraine B

    2018-01-01

    Increased endothelial permeability is central to shock and organ dysfunction in sepsis but therapeutics targeted to known mediators of increased endothelial permeability have been unsuccessful in patient studies. We previously reported that cell-free hemoglobin (CFH) is elevated in the majority of patients with sepsis and is associated with organ dysfunction, poor clinical outcomes and elevated markers of oxidant injury. Others have shown that Vitamin C (ascorbate) may have endothelial protective effects in sepsis. In this study, we tested the hypothesis that high levels of CFH, as seen in the circulation of patients with sepsis, disrupt endothelial barrier integrity. Human umbilical vein endothelial cells (HUVEC) were grown to confluence and treated with CFH with or without ascorbate. Monolayer permeability was measured by Electric Cell-substrate Impedance Sensing (ECIS) or transfer of 14 C-inulin. Viability was measured by trypan blue exclusion. Intracellular ascorbate was measured by HPLC. CFH increased permeability in a dose- and time-dependent manner with 1 mg/ml of CFH increasing inulin transfer by 50% without affecting cell viability. CFH (1 mg/ml) also caused a dramatic reduction in intracellular ascorbate in the same time frame (1.4 mM without CFH, 0.23 mM 18 h after 1 mg/ml CFH, p < 0.05). Pre-treatment of HUVECs with ascorbate attenuated CFH induced permeability. CFH increases endothelial permeability in part through depletion of intracellular ascorbate. Supplementation of ascorbate can attenuate increases in permeability mediated by CFH suggesting a possible therapeutic approach in sepsis. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Circulating endothelial cells and procoagulant microparticles in patients with glioblastoma: prognostic value.

    Directory of Open Access Journals (Sweden)

    Gaspar Reynés

    Full Text Available AIM: Circulating endothelial cells and microparticles are prognostic factors in cancer. However, their prognostic and predictive value in patients with glioblastoma is unclear. The objective of this study was to investigate the potential prognostic value of circulating endothelial cells and microparticles in patients with newly diagnosed glioblastoma treated with standard radiotherapy and concomitant temozolomide. In addition, we have analyzed the methylation status of the MGMT promoter. METHODS: Peripheral blood samples were obtained before and at the end of the concomitant treatment. Blood samples from healthy volunteers were also obtained as controls. Endothelial cells were measured by an immunomagnetic technique and immunofluorescence microscopy. Microparticles were quantified by flow cytometry. Microparticle-mediated procoagulant activity was measured by endogen thrombin generation and by phospholipid-dependent clotting time. Methylation status of MGMT promoter was determined by multiplex ligation-dependent probe amplification. RESULTS: Pretreatment levels of circulating endothelial cells and microparticles were higher in patients than in controls (p<0.001. After treatment, levels of microparticles and thrombin generation decreased, and phospholipid-dependent clotting time increased significantly. A high pretreatment endothelial cell count, corresponding to the 99(th percentile in controls, was associated with poor overall survival. MGMT promoter methylation was present in 27% of tumor samples and was associated to a higher overall survival (66 weeks vs 30 weeks, p<0.004. CONCLUSION: Levels of circulating endothelial cells may have prognostic value in patients with glioblastoma.

  12. Sugar Composition Analysis of Fuzi Polysaccharides by HPLC-MSn and Their Protective Effects on Schwann Cells Exposed to High Glucose

    Directory of Open Access Journals (Sweden)

    Bei-Bei Wang

    2016-11-01

    Full Text Available Fuzi has been used to treat diabetic complications for many years in china. In a previous study, we have shown that Fuzi aqueous extract can attenuate Diabetic peripheral neuropathy (DPN in rats and protect Schwann cells from injury. Thus, the protective effect of Fuzi polysaccharides (FPS on high glucose-induced SCs and the preliminary mechanism were investigated. Firstly, the FPS were obtained and their monose composition was analyzed by the combination of pre-column derivatization and high performance liquid chromatography coupled with electrospray ionization multi-tandem mass spectrometry (HPLC/ESI-MSn. The results witnessed the efficiency of this method and seven monosaccharides were tentatively identified, among which fucose was first reported. Simultaneously, m/z 215 can be considered as diagnostic ions to confirm the number of monosaccharides. Next, high glucose-induced SC model was applied and divided into model group, treated group of FPS, normal and osmotic control group. After treatment for 48 h, the data showed FPS could significantly decrease the intracellular ROS and apoptosis, which were determined by the corresponding fluorescent probes. Then, the expression of oxidative stress-related proteins in SCs were measured by Western blot. Furthermore, the protein tests found that FPS markedly up-regulated superoxide dismutase (SOD, catalase (CAT and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α protein level, but down-regulated NADPH oxidase-1 (Nox1 protein level. Moreover, FPS could also increase AMP-activated protein kinase (AMPK activation significantly. Hence, we preliminary deduced that AMPK-PGC-1α pathway may play an important role in the protective effect of FPS against high glucose-induced cell damage.

  13. Intracerebroventricular Kainic Acid-Induced Damage Affects Blood Glucose Level in d-glucose-fed Mouse Model.

    Science.gov (United States)

    Kim, Chea-Ha; Hong, Jae-Seung

    2015-03-01

    We have previously reported that the intracerebroventricular (i.c.v.) administration of kainic acid (KA) results in significant neuronal damage on the hippocampal CA3 region. In this study, we examined possible changes in the blood glucose level after i.c.v. pretreatment with KA. The blood glucose level was elevated at 30 min, began to decrease at 60 min and returned to normal at 120 min after D-glucose-feeding. We found that the blood glucose level in the KA-pretreated group was higher than in the saline-pretreated group. The up-regulation of the blood glucose level in the KA-pretreated group was still present even after 1~4 weeks. The plasma corticosterone and insulin levels were slightly higher in the KA-treated group. Corticosterone levels decreased whereas insulin levels were elevated when mice were fed with D-glucose. The i.c.v. pretreatment with KA for 24 hr caused a significant reversal of D-glucose-induced down-regulation of corticosterone level. However, the insulin level was enhanced in the KA-pretreated group compared to the vehicle-treated group when mice were fed with D-glucose. These results suggest that KA-induced alterations of the blood glucose level are related to cell death in the CA3 region whereas the up-regulation of blood glucose level in the KA-pretreated group appears to be due to a reversal of D-glucose feeding-induced down-regulation of corticosterone level.

  14. L-Cysteine supplementation increases adiponectin synthesis and secretion, and GLUT4 and glucose utilization by upregulating disulfide bond A-like protein expression mediated by MCP-1 inhibition in 3T3-L1 adipocytes exposed to high glucose.

    Science.gov (United States)

    Achari, Arunkumar Elumalai; Jain, Sushil K

    2016-03-01

    Adiponectin is an anti-diabetic and anti-atherogenic adipokine; its plasma levels are decreased in obesity, insulin resistance, and type 2 diabetes. An adiponectin-interacting protein named disulfide bond A-like protein (DsbA-L) plays an important role in the assembly of adiponectin. This study examined the hypothesis that L-cysteine (LC) regulates glucose homeostasis through the DsbA-L upregulation and synthesis and secretion of adiponectin in diabetes. 3T3L1 adipocytes were treated with LC (250 and 500 µM, 2 h) and high glucose (HG, 25 mM, 20 h). Results showed that LC supplementation significantly (p L, adiponectin, and GLUT-4 protein expression and glucose utilization in HG-treated adipocytes. LC supplementation significantly (p L expression and adiponectin levels in 3T3-L1 cells. Treatment with LC prevented the decrease in DsbA-L, adiponectin, and GLUT-4 expression in 3T3L1 adipocyte cells exposed to MCP-1. Thus, this study demonstrates that DsbA-L and adiponectin upregulation mediates the beneficial effects of LC on glucose utilization by inhibiting MCP-1 secretion in adipocytes and provides a novel mechanism by which LC supplementation can improve insulin sensitivity in diabetes.

  15. Sulodexide prevents activation of the PLA2/COX-2/VEGF inflammatory pathway in human retinal endothelial cells by blocking the effect of AGE/RAGE.

    Science.gov (United States)

    Giurdanella, Giovanni; Lazzara, Francesca; Caporarello, Nunzia; Lupo, Gabriella; Anfuso, Carmelina Daniela; Eandi, Chiara M; Leggio, Gian Marco; Drago, Filippo; Bucolo, Claudio; Salomone, Salvatore

    2017-10-15

    Diabetic retinopathy is characterized by the breakdown of endothelial blood-retinal barrier. We tested the hypothesis that sulodexide (SDX), a highly purified glycosaminoglycan composed of 80% iduronylglycosaminoglycan sulfate and 20% dermatan sulfate, protects human retinal endothelial cells (HREC) from high glucose (HG)-induced damage, through the suppression of inflammatory ERK/cPLA2/COX-2/PGE 2 pathway, by blocking the effect of advanced glycation end-products (AGEs). HREC were treated with HG (25mM) or AGEs (glycated-BSA, 2mg/ml) for 48h, with or without SDX (60μg/ml) or aflibercept (AFL, 40μg/ml), a VEGF-trap. SDX protected HREC from HG-induced damage (MTT and LDH release) and preserved their blood-retinal barrier-like properties (Trans Endothelial Electrical Resistance and junction proteins, claudin-5, VE-cadherin and occludin, immunofluorescence and immunoblot) as well as their angiogenic potential (Tube Formation Assay). Both HG and AGEs increased phosphoERK and phospho-cPLA 2 , an effect counteracted by SDX and, less efficiently, by AFL. Both HG and exogenous VEGF (80ng/ml) increased PGE 2 release, an effect partially reverted by SDX for HG and by AFL for VEGF. Analysis of NFκB activity revealed that HG increased the abundance of p65 in the nuclear fraction (nuclear translocation), an effect entirely reverted by SDX, but only partially by AFL. SDX, AFL and SDX+AFL protected HREC even when added 24h after HG. These data show that SDX protects HREC from HG damage and suggest that it counteracts the activation of ERK/cPLA2/COX-2/PGE 2 pathway by reducing AGE-related signaling and downstream NFκB activity. This mechanism, partially distinct from VEGF blockade, may contribute to the therapeutic effect of SDX. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Time-dependent change of blood flow in the prostate treated with high-intensity focused ultrasound.

    Science.gov (United States)

    Shoji, Sunao; Tonooka, Akiko; Hashimoto, Akio; Nakamoto, Masahiko; Tomonaga, Tetsuro; Nakano, Mayura; Sato, Haruhiro; Terachi, Toshiro; Koike, Junki; Uchida, Toyoaki

    2014-09-01

    Avascular areas on contrast-enhanced magnetic resonance imaging have been considered to be areas of localized prostate cancer successfully treated by high-intensity focused ultrasound. However, the optimal timing of magnetic resonance imaging has not been discussed. The thermal effect of high-intensity focused ultrasound is degraded by regional prostatic blood flow. Conversely, the mechanical effect of high-intensity focused ultrasound (cavitation) is not affected by blood flow, and can induce vessel damage. In this series, the longitudinal change of blood flow on contrast-enhanced magnetic resonance imaging was observed from postoperative day 1 to postoperative day 14 in 10 patients treated with high-intensity focused ultrasound. The median rates of increase in the non-enhanced volume of the whole gland, transition zone and peripheral zone from postoperative day 1 to postoperative day 14 were 36%, 39%, and 34%, respectively. In another pathological analysis of the prostate tissue of 17 patients immediately after high-intensity focused ultrasound without neoadjuvant hormonal therapy, we observed diffuse coagulative degeneration and partial non-coagulative prostate tissue around arteries with vascular endothelial cell detachment. These observations on contrast-enhanced magnetic resonance imaging support a time-dependent change of the blood flow in the prostate treated with high-intensity focused ultrasound. Additionally, our pathological findings support the longitudinal changes of these magnetic resonance imaging findings. Further large-scale studies will investigate the most appropriate timing of contrast-enhanced magnetic resonance imaging for evaluation of the effectiveness of high-intensity focused ultrasound for localized prostate cancer. © 2014 The Japanese Urological Association.

  17. Bevacizumab inhibits proliferation of choroidal endothelial cells by regulation of the cell cycle.

    Science.gov (United States)

    Rusovici, Raluca; Patel, Chirag J; Chalam, Kakarla V

    2013-01-01

    The purpose of this study was to evaluate cell cycle changes in choroidal endothelial cells treated with varying doses of bevacizumab in the presence of a range of concentrations of vascular endothelial growth factor (VEGF). Bevacizumab, a drug widely used in the treatment of neovascular age-related macular degeneration, choroidal neovascularization, and proliferative diabetic retinopathy, neutralizes all isoforms of VEGF. However, the effect of intravitreal administration of bevacizumab on the choroidal endothelial cell cycle has not been established. Monkey choroidal endothelial (RF/6A) cells were treated with VEGF 50 ng/mL and escalating doses of bevacizumab 0.1-2 mg/mL for 72 hours. Cell cycle changes in response to bevacizumab were analyzed by flow cytometry and propidium iodide staining. Cell proliferation was measured using the WST-1 assay. Morphological changes were recorded by bright field cell microscopy. Bevacizumab inhibited proliferation of choroidal endothelial cells by stabilization of the cell cycle in G0/G1 phase. Cell cycle analysis of VEGF-enriched choroidal endothelial cells revealed a predominant increase in the G2/M population (21.84%, P, 0.01) and a decrease in the G0/G1 phase population (55.08%, P, 0.01). Addition of escalating doses of bevacizumab stabilized VEGF-enriched cells in the G0/G1 phase (55.08%, 54.49%, 56.3%, and 64% [P, 0.01]) and arrested proliferation by inhibiting the G2/M phase (21.84%, 21.46%, 20.59%, 20.94%, and 16.1% [P, 0.01]). The increase in G0/G1 subpopulation in VEGF-enriched and bevacizumab-treated cells compared with VEGF-enriched cells alone was dose-dependent. Bevacizumab arrests proliferation of VEGF-enriched choroidal endothelial cells by stabilizing the cell cycle in the G0/G1 phase and inhibiting the G2/M phase in a dose-dependent fashion.

  18. High glucose recovery from direct enzymatic hydrolysis of bisulfite-pretreatment on non-detoxified furfural residues.

    Science.gov (United States)

    Xing, Yang; Bu, Lingxi; Sun, Dafeng; Liu, Zhiping; Liu, Shijie; Jiang, Jianxin

    2015-10-01

    This study reports four schemes to pretreat wet furfural residues (FRs) with sodium bisulfite for production of fermentable sugar. The results showed that non-detoxified FRs (pH 2-3) had great potential to lower the cost of bioconversion. The optimal process was that unwashed FRs were first pretreated with bisulfite, and the whole slurry was then directly used for enzymatic hydrolysis. A maximum glucose yield of 99.4% was achieved from substrates pretreated with 0.1 g NaHSO3/g dry substrate (DS), at a relatively low temperature of 100 °C for 3 h. Compared with raw material, enzymatic hydrolysis at a high-solid of 16.5% (w/w) specifically showed more excellent performance with bisulfite treated FRs. Direct bisulfite pretreatment improved the accessibility of substrates and the total glucose recovery. Lignosulfonate in the non-detoxified slurry decreased the non-productive adsorption of cellulase on the substrate, thus improving enzymatic hydrolysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Comparison of the effects of linagliptin and voglibose on endothelial function in patients with type 2 diabetes and coronary artery disease: a prospective, randomized, pilot study (EFFORT).

    Science.gov (United States)

    Koyama, Taku; Tanaka, Atsushi; Yoshida, Hisako; Oyama, Jun-Ichi; Toyoda, Shigeru; Sakuma, Masashi; Inoue, Teruo; Otsuka, Yoritaka; Node, Koichi

    2018-02-09

    Endothelial dysfunction contributes to poor cardiovascular prognosis in patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD). The effect of dipeptidyl peptidase-4 inhibitors on endothelial function remains controversial. We sought to compare the effects of linagliptin and voglibose on endothelial function, as assessed by reactive hyperemia-peripheral arterial tonometry (RH-PAT). Sixteen patients with newly diagnosed T2DM and CAD were randomized 1:1 to linagliptin (5 mg, once-daily) or voglibose (0.9 mg, thrice-daily). The RH-PAT and laboratory parameters, including 75 g oral glucose tolerance test, were measured at baseline and 3 months. Linagliptin increased serum levels of active glucagon-like peptide-1 and high-molecular-weight adiponectin. Age-, sex-, and baseline-adjusted changes in logarithmic RH-PAT index (LnRHI) after 3 months were significant between groups (linagliptin, 0.135 ± 0.097; voglibose, - 0.124 ± 0.091; P = 0.047). In the linagliptin group, change in LnRHI was positively correlated with change in high-density lipoprotein cholesterol and negatively correlated with changes in both urine albumin-to-creatinine ratio and high-sensitivity C-reactive protein. Furthermore, linagliptin treatment for 3 months reduced serum levels of both glucose and insulin at 2 h, relative to voglibose, in the age-, sex-, and baseline-adjusted model. Linagliptin improved endothelial function relative to voglibose, accompanied by amelioration of glycemic, renal, and cardiometabolic parameters, in patients with newly diagnosed T2DM and CAD.Trial registration Unique Trial Number, UMIN 000029169 ( https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000012442 ).

  20. Asymmetric Dimethylarginine Plasma Levels and Endothelial Function in Newly Diagnosed Type 2 Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Francesco Perticone

    2012-10-01

    Full Text Available It is now well established that major risk factors for cardiovascular diseases (CVD impact upon endothelial function by decreasing nitric oxide (NO bioavailability. Asymmetric dimethylarginine (ADMA, an endogenous analog of l-arginine, is able to inhibit the activity of endothelial-NO synthase, promoting endothelial dysfunction. Type 2 diabetes (T2D is characterized by a reduced endothelium-dependent vasodilation and increased ADMA levels and ADMA is strongly associated with micro- and macrovascular diabetic complications. However, there are not a lot of data about the role of ADMA on endothelial function in newly diagnosed T2D patients without cardiovascular (CV complications. For this aim, we have enrolled forty-five newly diagnosed T2D patients, evaluated by a oral glucose tolerance test, and thirty normal subjects. Endothelium-dependent and -independent vasodilatation was investigated by intra-arterial infusion of increasing doses of acetylcholine (ACh and sodium nitroprusside. ADMA was measured by high-performance liquid chromatography and insulin resistance (IR by HOMA. Newly diagnosed T2D patients showed higher ADMA and l-arginine mean values in comparison with normal subjects and a significantly reduced ACh-stimulated forearm blood flow (FBF. In T2D patients FBF was significantly and inversely correlated with ADMA (r = −0.524, p < 0.0001 and in a multivariate regression analysis, ADMA resulted the stronger predictor of FBF, explaining the 27.5% of variability (p < 0.0001. In conclusion, ADMA was strongly related to endothelial dysfunction also in patients with newly diagnosed T2D, without clinically manifest vascular complications. This field is of great interest for understanding the mechanisms underlying the pathogenesis of diabetic disease and its CV complications.

  1. High Sensitivity and High Detection Specificity of Gold-Nanoparticle-Grafted Nanostructured Silicon Mass Spectrometry for Glucose Analysis.

    Science.gov (United States)

    Tsao, Chia-Wen; Yang, Zhi-Jie

    2015-10-14

    Desorption/ionization on silicon (DIOS) is a high-performance matrix-free mass spectrometry (MS) analysis method that involves using silicon nanostructures as a matrix for MS desorption/ionization. In this study, gold nanoparticles grafted onto a nanostructured silicon (AuNPs-nSi) surface were demonstrated as a DIOS-MS analysis approach with high sensitivity and high detection specificity for glucose detection. A glucose sample deposited on the AuNPs-nSi surface was directly catalyzed to negatively charged gluconic acid molecules on a single AuNPs-nSi chip for MS analysis. The AuNPs-nSi surface was fabricated using two electroless deposition steps and one electroless etching step. The effects of the electroless fabrication parameters on the glucose detection efficiency were evaluated. Practical application of AuNPs-nSi MS glucose analysis in urine samples was also demonstrated in this study.

  2. Glucose Homeostasis During Short-term and Prolonged Exposure to High Altitudes

    Science.gov (United States)

    Ader, Marilyn; Bergman, Richard N.

    2015-01-01

    Most of the literature related to high altitude medicine is devoted to the short-term effects of high-altitude exposure on human physiology. However, long-term effects of living at high altitudes may be more important in relation to human disease because more than 400 million people worldwide reside above 1500 m. Interestingly, individuals living at higher altitudes have a lower fasting glycemia and better glucose tolerance compared with those who live near sea level. There is also emerging evidence of the lower prevalence of both obesity and diabetes at higher altitudes. The mechanisms underlying improved glucose control at higher altitudes remain unclear. In this review, we present the most current evidence about glucose homeostasis in residents living above 1500 m and discuss possible mechanisms that could explain the lower fasting glycemia and lower prevalence of obesity and diabetes in this population. Understanding the mechanisms that regulate and maintain the lower fasting glycemia in individuals who live at higher altitudes could lead to new therapeutics for impaired glucose homeostasis. PMID:25675133

  3. Effects of self-monitoring of glucose on distress and self-efficacy in people with non-insulin-treated Type 2 diabetes: a randomized controlled trial

    NARCIS (Netherlands)

    Malanda, U. L.; Bot, S. D. M.; Kostense, P. J.; Snoek, F. J.; Dekker, J. M.; Nijpels, G.

    2016-01-01

    To investigate the effects of self-monitoring of glucose in blood or urine, on diabetes-specific distress and self-efficacy, compared with usual care in people with non-insulin-treated Type 2 diabetes mellitus. One hundred and eighty-one participants with non-insulin-treated Type 2 diabetes mellitus

  4. High glucose suppresses embryonic stem cell differentiation into neural lineage cells

    OpenAIRE

    Yang, Penghua; Shen, Wei-bin; Reece, E. Albert; Chen, Xi; Yang, Peixin

    2016-01-01

    Abnormal neurogenesis occurs during embryonic development in human diabetic pregnancies and in animal models of diabetic embryopathy. Our previous studies in a mouse model of diabetic embryopathy have implicated that high glucose of maternal diabetes delays neurogenesis in the developing neuroepithelium leading to neural tube defects. However, the underlying process in high glucose-impaired neurogenesis is uncharacterized. Neurogenesis from embryonic stem (ES) cells provides a valuable model ...

  5. Noninvasive ultrasound molecular imaging of the effect of statins on endothelial inflammatory phenotype in early atherosclerosis.

    Directory of Open Access Journals (Sweden)

    Elham Khanicheh

    Full Text Available BACKGROUND/OBJECTIVES: Inflammatory changes on the endothelium are responsible for leukocyte recruitment to plaques in atherosclerosis. Noninvasive assessment of treatment-effects on endothelial inflammation may be of use for managing medical therapy and developing novel therapies. We hypothesized that molecular imaging of vascular cell adhesion molecule-1 (VCAM-1 with contrast enhanced ultrasound (CEU could assess treatment effects on endothelial phenotype in early atherosclerosis. METHODS: Mice with atherosclerosis produced by gene deletion of the LDL-receptor and Apobec-1-editing protein were studied. At 12 weeks of age, mice received 8 weeks of regular chow or atorvastatin-enriched chow (10 mg/kg/day. At 20 weeks, CEU molecular imaging for aortic endothelial VCAM-1 expression was performed with VCAM-1-targeted (MB(VCAM and control microbubbles (MB(Ctr. Aortic wall thickness was assessed with high frequency ultrasound. Histology, immunohistology and Western blot were used to assess plaque burden and VCAM-1 expression. RESULTS: Plaque burden was reduced on histology, and VCAM-1 was reduced on Western blot by atorvastatin, which corresponded to less endothelial expression of VCAM-1 on immunohistology. High frequency ultrasound did not detect differences in aortic wall thickness between groups. In contrast, CEU molecular imaging demonstrated selective signal enhancement for MB(VCAM in non-treated animals (MB(VCAM 2±0.3 vs MB(Ctr 0.7±0.2, p<0.01, but not in statin-treated animals (MB(VCAM 0.8±0.2 vs MB(Ctr 1.0±0.2, p = ns; p<0.01 for the effect of statin on MB(VCAM signal. CONCLUSIONS: Non-invasive CEU molecular imaging detects the effects of anti-inflammatory treatment on endothelial inflammation in early atherosclerosis. This easily accessible, low-cost technique may be useful in assessing treatment effects in preclinical research and in patients.

  6. Atherosclerosis-Associated Endothelial Cell Apoptosis by MiR-429-Mediated Down Regulation of Bcl-2

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    Tao Zhang

    2015-10-01

    Full Text Available Background/Aims: Endothelial cell injury and subsequent apoptosis play a key role in the development and pathogenesis of atherosclerosis, which is hallmarked by dysregulated lipid homeostasis, aberrant immunity and inflammation, and plaque-instability-associated coronary occlusion. Nevertheless, our understanding of the mechanisms underlying endothelial cell apoptosis is still limited. MicroRNA-429 (miR-29 is a known cancer suppressor that promotes cancer cell apoptosis. However, it is unknown whether miR-429 may be involved in the development of atherosclerosis through similar mechanisms. We addressed these questions in the current study. Methods: We examined the levels of endothelial cell apoptosis in ApoE (-/- mice suppled with high-fat diet (HFD, a mouse model for atherosclerosis (simplified as HFD mice. We analyzed the levels of anti-apoptotic protein Bcl-2 and the levels of miR-429 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-429 and 3'-UTR of Bcl-2 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-429 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL-treated human aortic endothelial cells (HAECs. Results: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/- mice that had received normal diet (simplified as NOR mice did not. HFD mice had significantly lower percentage of endothelial cells and significantly higher percentage of mesenchymal cells in the aorta than NOR mice. Significantly higher levels of endothelial cell apoptosis were detected in HFD mice, resulting from decreases in Bcl-2 protein, but not mRNA. The decreases in Bcl-2 in endothelial cells were due to increased levels of miR-429, which suppressed the translation of Bcl-2 mRNA via 3'-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. Conclusion: Atherosclerosis

  7. Pancreatic alpha-cell dysfunction contributes to the disruption of glucose homeostasis and compensatory insulin hypersecretion in glucocorticoid-treated rats.

    Directory of Open Access Journals (Sweden)

    Alex Rafacho

    Full Text Available Glucocorticoid (GC-based therapies can cause insulin resistance (IR, glucose intolerance, hyperglycemia and, occasionally, overt diabetes. Understanding the mechanisms behind these metabolic disorders could improve the management of glucose homeostasis in patients undergoing GC treatment. For this purpose, adult rats were treated with a daily injection of dexamethasone (1 mg/kg b.w., i.p. (DEX or saline as a control for 5 consecutive days. The DEX rats developed IR, augmented glycemia, hyperinsulinemia and hyperglucagonemia. Treatment of the DEX rats with a glucagon receptor antagonist normalized their blood glucose level. The characteristic inhibitory effect of glucose on glucagon secretion was impaired in the islets of the DEX rats, while no direct effects were found on α-cells in islets that were incubated with DEX in vitro. A higher proportion of docked secretory granules was found in the DEX α-cells as well as a trend towards increased α-cell mass. Additionally, insulin secretion in the presence of glucagon was augmented in the islets of the DEX rats, which was most likely due to their higher glucagon receptor content. We also found that the enzyme 11βHSD-1, which participates in GC metabolism, contributed to the insulin hypersecretion in the DEX rats under basal glucose conditions. Altogether, we showed that GC treatment induces hyperglucagonemia, which contributes to an imbalance in glucose homeostasis and compensatory β-cell hypersecretion. This hyperglucagonemia may result from altered α-cell function and, likely, α-cell mass. Additionally, blockage of the glucagon receptor seems to be effective in preventing the elevation in blood glucose levels induced by GC administration.

  8. Vildagliptin Stimulates Endothelial Cell Network Formation and Ischemia-induced Revascularization via an Endothelial Nitric-oxide Synthase-dependent Mechanism*

    Science.gov (United States)

    Ishii, Masakazu; Shibata, Rei; Kondo, Kazuhisa; Kambara, Takahiro; Shimizu, Yuuki; Tanigawa, Tohru; Bando, Yasuko K.; Nishimura, Masahiro; Ouchi, Noriyuki; Murohara, Toyoaki

    2014-01-01

    Dipeptidyl peptidase-4 inhibitors are known to lower glucose levels and are also beneficial in the management of cardiovascular disease. Here, we investigated whether a dipeptidyl peptidase-4 inhibitor, vildagliptin, modulates endothelial cell network formation and revascularization processes in vitro and in vivo. Treatment with vildagliptin enhanced blood flow recovery and capillary density in the ischemic limbs of wild-type mice, with accompanying increases in phosphorylation of Akt and endothelial nitric-oxide synthase (eNOS). In contrast to wild-type mice, treatment with vildagliptin did not improve blood flow in ischemic muscles of eNOS-deficient mice. Treatment with vildagliptin increased the levels of glucagon-like peptide-1 (GLP-1) and adiponectin, which have protective effects on the vasculature. Both vildagliptin and GLP-1 increased the differentiation of cultured human umbilical vein endothelial cells (HUVECs) into vascular-like structures, although vildagliptin was less effective than GLP-1. GLP-1 and vildagliptin also stimulated the phosphorylation of Akt and eNOS in HUVECs. Pretreatment with a PI3 kinase or NOS inhibitor blocked the stimulatory effects of both vildagliptin and GLP-1 on HUVEC differentiation. Furthermore, treatment with vildagliptin only partially increased the limb flow of ischemic muscle in adiponectin-deficient mice in vivo. GLP-1, but not vildagliptin, significantly increased adiponectin expression in differentiated 3T3-L1 adipocytes in vitro. These data indicate that vildagliptin promotes endothelial cell function via eNOS signaling, an effect that may be mediated by both GLP-1-dependent and GLP-1-independent mechanisms. The beneficial activity of GLP-1 for revascularization may also be partially mediated by its ability to increase adiponectin production. PMID:25100725

  9. Red wine consumption improves in vitro migration of endothelial progenitor cells in young, healthy individuals.

    Science.gov (United States)

    Hamed, Saher; Alshiek, Jonia; Aharon, Anat; Brenner, Benjamin; Roguin, Ariel

    2010-07-01

    Endothelial progenitor cells (EPCs) contribute to the maintenance of vascular endothelial function. The moderate consumption of red wine provides cardiovascular protection. We investigated the underlying molecular mechanism of EPC migration in young, healthy individuals who drank red wine. Fourteen healthy volunteers consumed 250 mL red wine daily for 21 consecutive days. Vascular endothelial function, plasma stromal cell-derived factor 1alpha (SDF1alpha) concentrations, and the number, migration, and nitric oxide production of EPCs were determined before and after the daily consumption of red wine. EPCs were glucose stressed to study the effect of red wine on EPC migration, proliferation, and senescence and to study the expressions of CXC chemokine receptor 4 (CXCR4) and members of the Pi3K/Akt/eNOS (phosphatidylinositol 3-kinase/protein kinase B/endothelial nitric oxide synthase) signaling pathway by Western blotting. Daily red wine consumption for 21 consecutive days significantly enhanced vascular endothelial function. Although plasma SDF1alpha concentrations were unchanged, EPC count and migration were significantly increased after this 21-d consumption period. Red wine increased the migration, proliferation, CXCR4 expression, and activity of the Pi3K/Akt/eNOS signaling pathway and decreased the extent of apoptosis in glucose-stressed EPCs. The results of the present study indicate that red wine exerts its effect through the up-regulation of CXCR4 expression and activation of the SDF1alpha/CXCR4/Pi3K/Akt/eNOS signaling pathway, which results in increased EPC migration and proliferation and decreased extent of apoptosis. Our findings suggest that these effects could be linked to the mechanism of cardiovascular protection that is associated with the regular consumption of red wine.

  10. Magnetizable stent-grafts enable endothelial cell capture

    Science.gov (United States)

    Tefft, Brandon J.; Uthamaraj, Susheil; Harburn, J. Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

  11. Magnetizable stent-grafts enable endothelial cell capture

    Energy Technology Data Exchange (ETDEWEB)

    Tefft, Brandon J. [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Uthamaraj, Susheil [Division of Engineering, Mayo Clinic, Rochester, MN (United States); Harburn, J. Jonathan [School of Medicine, Pharmacy and Health, Durham University, Stockton-on-Tees (United Kingdom); Hlinomaz, Ota [Department of Cardioangiology, St. Anne' s University Hospital, Brno (Czech Republic); Lerman, Amir [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Dragomir-Daescu, Dan [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN (United States); Sandhu, Gurpreet S., E-mail: sandhu.gurpreet@mayo.edu [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States)

    2017-04-01

    Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance. - Highlights: • Magnetic stent-grafts were made from 2205 steel stents and polyurethane nanofibers. • Stent-grafts remained patent and formed a thin and uniform neointima when implanted. • Stent-grafts captured endothelial cells labeled with magnetic nanoparticles.

  12. Chronic benzylamine administration in the drinking water improves glucose tolerance, reduces body weight gain and circulating cholesterol in high-fat diet-fed mice.

    Science.gov (United States)

    Iffiú-Soltész, Zsuzsa; Wanecq, Estelle; Lomba, Almudena; Portillo, Maria P; Pellati, Federica; Szöko, Eva; Bour, Sandy; Woodley, John; Milagro, Fermin I; Alfredo Martinez, J; Valet, Philippe; Carpéné, Christian

    2010-04-01

    Benzylamine is found in Moringa oleifera, a plant used to treat diabetes in traditional medicine. In mammals, benzylamine is metabolized by semicarbazide-sensitive amine oxidase (SSAO) to benzaldehyde and hydrogen peroxide. This latter product has insulin-mimicking action, and is involved in the effects of benzylamine on human adipocytes: stimulation of glucose transport and inhibition of lipolysis. This study examined whether chronic, oral administration of benzylamine could improve glucose tolerance and the circulating lipid profile without increasing oxidative stress in overweight and pre-diabetic mice. The benzylamine diffusion across the intestine was verified using everted gut sacs. Then, glucose handling and metabolic markers were measured in mice rendered insulin-resistant when fed a high-fat diet (HFD) and receiving or not benzylamine in their drinking water (3600micromol/(kgday)) for 17 weeks. HFD-benzylamine mice showed lower body weight gain, fasting blood glucose, total plasma cholesterol and hyperglycaemic response to glucose load when compared to HFD control. In adipocytes, insulin-induced activation of glucose transport and inhibition of lipolysis remained unchanged. In aorta, benzylamine treatment partially restored the nitrite levels that were reduced by HFD. In liver, lipid peroxidation markers were reduced. Resistin and uric acid, surrogate plasma markers of metabolic syndrome, were decreased. In spite of the putative deleterious nature of the hydrogen peroxide generated during amine oxidation, and in agreement with its in vitro insulin-like actions found on adipocytes, the SSAO-substrate benzylamine could be considered as a potential oral agent to treat metabolic syndrome. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. High glucose variability is associated with poor neurodevelopmental outcomes in neonatal hypoxic ischemic encephalopathy.

    Science.gov (United States)

    Al Shafouri, N; Narvey, M; Srinivasan, G; Vallance, J; Hansen, G

    2015-01-01

    In neonatal hypoxic ischemic encephalopathy (HIE), hypo- and hyperglycemia have been associated with poor outcomes. However, glucose variability has not been reported in this population. To examine the association between serum glucose variability within the first 24 hours and two-year neurodevelopmental outcomes in neonates cooled for HIE. In this retrospective cohort study, glucose, clinical and demographic data were documented from 23 term newborns treated with whole body therapeutic hypothermia. Severe neurodevelopmental outcomes from planned two-year assessments were defined as the presence of any one of the following: Gross Motor Function Classification System levels 3 to 5, Bayley III Motor Standard Score neurodevelopmental outcomes from 8 of 23 patients were considered severe, and this group demonstrated a significant increase of mean absolute glucose (MAG) change (-0.28 to -0.03, 95% CI, p = 0.032). There were no significant differences between outcome groups with regards to number of patients with hyperglycemic means, one or multiple hypo- or hyperglycemic measurement(s). There were also no differences between both groups with mean glucose, although mean glucose standard deviation was approaching significance. Poor neurodevelopmental outcomes in whole body cooled HIE neonates are significantly associated with MAG changes. This information may be relevant for prognostication and potential management strategies.

  14. Dexamethasone increases glucose cycling, but not glucose production, in healthy subjects

    International Nuclear Information System (INIS)

    Wajngot, A.; Khan, A.; Giacca, A.; Vranic, M.; Efendic, S.

    1990-01-01

    We established that measurement of glucose fluxes through glucose-6-phosphatase (G-6-Pase; hepatic total glucose output, HTGO), glucose cycling (GC), and glucose production (HGP), reveals early diabetogenic changes in liver metabolism. To elucidate the mechanism of the diabetogenic effect of glucocorticoids, we treated eight healthy subjects with oral dexamethasone (DEX; 15 mg over 48 h) and measured HTGO with [2-3H]glucose and HGP with [6-3H]glucose postabsorptively and during a 2-h glucose infusion (11.1 mumol.kg-1.min-1). [2-3H]- minus [6-3H]glucose equals GC. DEX significantly increased plasma glucose, insulin, C peptide, and HTGO, while HGP was unchanged. In controls and DEX, glucose infusion suppressed HTGO (82 vs. 78%) and HGP (87 vs. 91%). DEX increased GC postabsorptively (three-fold) P less than 0.005 and during glucose infusion (P less than 0.05) but decreased metabolic clearance and glucose uptake (Rd), which eventually normalized, however. Because DEX increased HTGO (G-6-Pase) and not HGP (glycogenolysis + gluconeogenesis), we assume that DEX increases HTGO and GC in humans by activating G-6-Pase directly, rather than by expanding the glucose 6-phosphate pool. Hyperglycemia caused by peripheral effects of DEX can also contribute to an increase in GC by activating glucokinase. Therefore, measurement of glucose fluxes through G-6-Pase and GC revealed significant early effects of DEX on hepatic glucose metabolism, which are not yet reflected in HGP

  15. High-performance glucose biosensor based on chitosan-glucose oxidase immobilized polypyrrole/Nafion/functionalized multi-walled carbon nanotubes bio-nanohybrid film.

    Science.gov (United States)

    Shrestha, Bishnu Kumar; Ahmad, Rafiq; Mousa, Hamouda M; Kim, In-Gi; Kim, Jeong In; Neupane, Madhav Prasad; Park, Chan Hee; Kim, Cheol Sang

    2016-11-15

    A highly electroactive bio-nanohybrid film of polypyrrole (PPy)-Nafion (Nf)-functionalized multi-walled carbon nanotubes (fMWCNTs) nanocomposite was prepared on the glassy carbon electrode (GCE) by a facile one-step electrochemical polymerization technique followed by chitosan-glucose oxidase (CH-GOx) immobilization on its surface to achieve a high-performance glucose biosensor. The as-fabricated nanohybrid composite provides high surface area for GOx immobilization and thus enhances the enzyme-loading efficiency. The structural characterization revealed that the PPy-Nf-fMWCNTs nanocomposite films were uniformly formed on GCE and after GOx immobilization, the surface porosities of the film were decreased due to enzyme encapsulation inside the bio-nanohybrid composite materials. The electrochemical behavior of the fabricated biosensor was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry measurements. The results indicated an excellent catalytic property of bio-nanohybrid film for glucose detection with improved sensitivity of 2860.3μAmM(-1)cm(-2), the linear range up to 4.7mM (R(2)=0.9992), and a low detection limit of 5μM under a signal/noise (S/N) ratio of 3. Furthermore, the resulting biosensor presented reliable selectivity, better long-term stability, good repeatability, reproducibility, and acceptable measurement of glucose concentration in real serum samples. Thus, this fabricated biosensor provides an efficient and highly sensitive platform for glucose sensing and can open up new avenues for clinical applications. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Glucosamine exposure reduces proteoglycan synthesis in primary human endothelial cells in vitro

    Directory of Open Access Journals (Sweden)

    Trine M. Reine

    2016-09-01

    Full Text Available Purpose: Glucosamine (GlcN supplements are promoted for medical reasons, for example, for patients with arthritis and other joint-related diseases. Oral intake of GlcN is followed by uptake in the intestine, transport in the circulation and thereafter delivery to chondrocytes. Here, it is postulated to have an effect on synthesis and turnover of extracellular matrix constituents expressed by these cells. Following uptake in the intestine, serum levels are transiently increased, and the endothelium is exposed to increased levels of GlcN. We investigated the possible effects of GlcN on synthesis of proteoglycans (PGs, an important matrix component, in primary human endothelial cells. Methods: Primary human endothelial cells were cultured in vitro in medium with 5 mM glucose and 0–10 mM GlcN. PGs were recovered and analysed by western blotting, or by SDS-PAGE, gel chromatography or ion-exchange chromatography of 35S-PGs after 35S-sulphate labelling of the cells. Results: The synthesis and secretion of 35S-PGs from cultured endothelial cells were reduced in a dose- and time-dependent manner after exposure to GlcN. PGs are substituted with sulphated glycosaminoglycan (GAG chains, vital for PG function. The reduction in 35S-PGs was not related to an effect on GAG chain length, number or sulphation, but rather to the total expression of PGs. Conclusion: Exposure of endothelial cells to GlcN leads to a general decrease in 35S-PG synthesis. These results suggest that exposure to high levels of GlcN can lead to decreased matrix synthesis, contrary to what has been claimed by supporters of such supplements.

  17. The Effects of High Glucose on Adipogenic and Osteogenic Differentiation of Gestational Tissue-Derived MSCs

    Directory of Open Access Journals (Sweden)

    Weerawan Hankamolsiri

    2016-01-01

    Full Text Available Most type 2 diabetic patients are obese who have increased number of visceral adipocytes. Those visceral adipocytes release several factors that enhance insulin resistance making diabetic treatment ineffective. It is known that significant percentages of visceral adipocytes are derived from mesenchymal stem cells and high glucose enhances adipogenic differentiation of mouse bone marrow-derived MSCs (BM-MSCs. However, the effect of high glucose on adipogenic differentiation of human bone marrow and gestational tissue-derived MSCs is still poorly characterized. This study aims to investigate the effects of high glucose on proliferation as well as adipogenic and osteogenic differentiation of human MSCs derived from bone marrow and several gestational tissues including chorion, placenta, and umbilical cord. We found that high glucose reduced proliferation but enhanced adipogenic differentiation of all MSCs examined. The expression levels of some adipogenic genes were also upregulated when MSCs were cultured in high glucose. Although high glucose transiently downregulated the expression levels of some osteogenic genes examined, its effect on the osteogenic differentiation levels of the MSCs is not clearly demonstrated. The knowledge gained from this study will increase our understanding about the effect of high glucose on adipogenic differentiation of MSCs and might lead to an improvement in the diabetic treatment in the future.

  18. Deletion of Protein Tyrosine Phosphatase 1B (PTP1B Enhances Endothelial Cyclooxygenase 2 Expression and Protects Mice from Type 1 Diabetes-Induced Endothelial Dysfunction.

    Directory of Open Access Journals (Sweden)

    David J Herren

    Full Text Available Protein tyrosine phosphatase 1B (PTP1B dephosphorylates receptors tyrosine kinase and acts as a molecular brake on insulin signaling pathway. Conditions of metabolic dysfunction increase PTP1B, when deletion of PTP1B protects against metabolic disorders by increasing insulin signaling. Although vascular insulin signaling contributes to the control of glucose disposal, little is known regarding the direct role of PTP1B in the control of endothelial function. We hypothesized that metabolic dysfunctions increase PTP1B expression in endothelial cells and that PTP1B deletion prevents endothelial dysfunction in situation of diminished insulin secretion. Type I diabetes (T1DM was induced in wild-type (WT and PTP1B-deficient mice (KO with streptozotocin (STZ injection. After 28 days of T1DM, KO mice exhibited a similar reduction in body weight and plasma insulin levels and a comparable increase in glycemia (WT: 384 ± 20 vs. Ko: 432 ± 29 mg/dL, cholesterol and triglycerides, as WT mice. T1DM increased PTP1B expression and impaired endothelial NO-dependent relaxation, in mouse aorta. PTP1B deletion did not affect baseline endothelial function, but preserved endothelium-dependent relaxation, in T1DM mice. NO synthase inhibition with L-NAME abolished endothelial relaxation in control and T1DM WT mice, whereas L-NAME and the cyclooxygenases inhibitor indomethacin were required to abolish endothelium relaxation in T1DM KO mice. PTP1B deletion increased COX-2 expression and PGI2 levels, in mouse aorta and plasma respectively, in T1DM mice. In parallel, simulation of diabetic conditions increased PTP1B expression and knockdown of PTP1B increased COX-2 but not COX-1 expression, in primary human aortic endothelial cells. Taken together these data indicate that deletion of PTP1B protected endothelial function by compensating the reduction in NO bioavailability by increasing COX-2-mediated release of the vasodilator prostanoid PGI2, in T1DM mice.

  19. Reduced saphenous vein prostacyclin production in the absence of endothelial detachment

    International Nuclear Information System (INIS)

    De Caterina, R.; Cruz-Bracho, M.R.; Alonso, D.R.; Subramanian, V.A.; Weksler, B.B.

    1988-01-01

    High-potassium cardioplegic solutions have been suspected of inducing vascular damage at coronary bypass surgery. In this study the authors compared prostacyclin production and endothelial morphology in saphenous vein segments perfused either with cardioplegic solutions with a potassium concentration of 20, 40 and 80 mEq/1, or with a control buffer (1) at 4 grade centigrades for 30 min; (2) at 37 grade centigrades for 15 min; (3) at 37 grade centigrades for 15 min after the addition of arachidonic acid. Prostacyclin production (6-keto-PGF 1α , pg/ml cm 2 endothelial surface area) in control treated segments was a function of temperature and of substrute availability, being (mean±SEM) 62.4±8.2 in setting (1); 309±34.7 in setting (2); and 1515.4±205.2 in setting (3). Cardioplegic solution containing 20 mEq/1 potassium did not alter prostacyclin production in any of these settings, whereas exposure of tissue to the 40 mEq/1 potassium solution decreased prostacyclin production in setting (21) and (2), and the solution containing 80 mEq/1 potassium decreased prostacyclin production in all three experimental conditions. Absence of endothelial detachment in all experimental settings was documented by immunoperoxidase staining of vascular cross-sections for the specific endothelial marker Factor VIII - related antigen and staining of ''en face'' preparations of endothelial surface with silver nitrate and silver nitrate-hematoxylin. These data indicate that cardioplegic solutions with a potassium concentration equal or greater than 40 mEq/1 can induce morphologically silent endothelial damage manifested by decreased prostacyclin production. The use of these solutions may predispose to possible thrombogenicity after coronary bypass surgery

  20. SNF3 as high affinity glucose sensor and its function in supporting the viability of Candida glabrata under glucose-limited environment

    Directory of Open Access Journals (Sweden)

    Tzu Shan eNg

    2015-12-01

    Full Text Available Candida glabrata is an emerging human fungal pathogen that has efficacious nutrient sensing and responsiveness ability. It can be seen through its ability to thrive in diverse range of nutrient limited-human anatomical sites. Therefore, nutrient sensing particularly glucose sensing is thought to be crucial in contributing to the development and fitness of the pathogen. This study aimed to elucidate the role of SNF3 (Sucrose Non Fermenting 3 as a glucose sensor and its possible role in contributing to the fitness and survivability of C. glabrata in glucose-limited environment. The SNF3 knockout strain was constructed and subjected to different glucose concentrations to evaluate its growth, biofilm formation, amphotericin B susceptibility, ex vivo survivability and effects on the transcriptional profiling of the sugar receptor repressor (SRR pathway-related genes. The SNF3Δ strain showed a retarded growth in low glucose environments (0.01% and 0.1% in both fermentation and respiration-preferred conditions but grew well in high glucose concentration environments (1% and 2%. It was also found to be more susceptible to amphotericin B in low glucose environment (0.1% and macrophage engulfment but showed no difference in the biofilm formation capability. The deletion of SNF3 also resulted in the down-regulation of about half of hexose transporters genes (4 out of 9. Overall, the deletion of SNF3 causes significant reduction in the ability of C. glabrata to sense limited surrounding glucose and consequently disrupts its competency to transport and perform the uptake of this critical nutrient. This study highlighted the role of SNF3 as a high affinity glucose sensor and its role in aiding the survivability of C. glabrata particularly in glucose limited environment.

  1. Endothelial Dysfunction Plays a Key Role in Increasing Cardiovascular Risk in Type 2 Diabetes The Hoorn Study

    NARCIS (Netherlands)

    van Sloten, T.T.; Henry, R.M.A.; Dekker, J.M.; Nijpels, G.; Unger, T.; Schram, M.T.; Stehouwer, C.D.A.

    2014-01-01

    In the pathogenesis of cardiovascular events, interaction between risk factors has seldom been identified. However, endothelial dysfunction on the one hand and type 2 diabetes mellitus, impaired glucose metabolism (IGM), and insulin resistance on the other may act synergistically (ie, interact) in

  2. Astrocyte–endothelial interactions and blood–brain barrier permeability*

    Science.gov (United States)

    Abbott, N Joan

    2002-01-01

    The blood–brain barrier (BBB) is formed by brain endothelial cells lining the cerebral microvasculature, and is an important mechanism for protecting the brain from fluctuations in plasma composition, and from circulating agents such as neurotransmitters and xenobiotics capable of disturbing neural function. The barrier also plays an important role in the homeostatic regulation of the brain microenvironment necessary for the stable and co-ordinated activity of neurones. The BBB phenotype develops under the influence of associated brain cells, especially astrocytic glia, and consists of more complex tight junctions than in other capillary endothelia, and a number of specific transport and enzyme systems which regulate molecular traffic across the endothelial cells. Transporters characteristic of the BBB phenotype include both uptake mechanisms (e.g. GLUT-1 glucose carrier, L1 amino acid transporter) and efflux transporters (e.g. P-glycoprotein). In addition to a role in long-term barrier induction and maintenance, astrocytes and other cells can release chemical factors that modulate endothelial permeability over a time-scale of seconds to minutes. Cell culture models, both primary and cell lines, have been used to investigate aspects of barrier induction and modulation. Conditioned medium taken from growing glial cells can reproduce some of the inductive effects, evidence for involvement of diffusible factors. However, for some features of endothelial differentiation and induction, the extracellular matrix plays an important role. Several candidate molecules have been identified, capable of mimicking aspects of glial-mediated barrier induction of brain endothelium; these include TGFβ, GDNF, bFGF, IL-6 and steroids. In addition, factors secreted by brain endothelial cells including leukaemia inhibitory factor (LIF) have been shown to induce astrocytic differentiation. Thus endothelium and astrocytes are involved in two-way induction. Short-term modulation of brain

  3. High activity enables life on a high-sugar diet : blood glucose regulation in nectar-feeding bats

    NARCIS (Netherlands)

    Kelm, Detlev H; Simon, Ralph; Kuhlow, Doreen; Voigt, Christian C; Ristow, Michael

    2011-01-01

    High blood glucose levels caused by excessive sugar consumption are detrimental to mammalian health and life expectancy. Despite consuming vast quantities of sugar-rich floral nectar, nectar-feeding bats are long-lived, provoking the question of how they regulate blood glucose. We investigated blood

  4. Highly sensitive antibody-aptamer sensor for vascular endothelial growth factor based on hybridization chain reaction and pH meter/indicator.

    Science.gov (United States)

    Xu, Huifeng; Kou, Fangxia; Ye, Hongzhi; Wang, Zongwen; Huang, Suixin; Liu, Xianxiang; Zhu, Xi; Lin, Zhenyu; Chen, Guonan

    2017-12-01

    Vascular endothelial growth factor (VEGF) is a crucial signaling protein for the tumor growth and metastasis, which is also acted as the biomarkers for various diseases. In this research, we fabricate an aptamer-antibody sensor for point-of-care test of VEGF. Firstly, target VEGF is captured by antibody immobilized on the microplate, and then binds with aptamer to form the sandwich structure. Next, with the assist of glucose oxidase (GOx)-functionalized ssDNAs, hybridization chain reaction occurs using the aptamer as the primer. Thus, GOx are greatly gathered on the microplate, which catalyzes the oxidization of glucose, leading to the pH change. As a result, the detect limit at a signal-to-noise was estimated to be 0.5pg/mL of target by pH meter, and 1.6pg/mL of VEGF was able to be distinguished by naked eyes. Meanwhile, this method has been used assay VEGF in the serum with the satisfactory results. Copyright © 2017. Published by Elsevier B.V.

  5. High performance separation of xylose and glucose by enzyme assisted nanofiltration

    DEFF Research Database (Denmark)

    Morthensen, Sofie Thage; Luo, Jianquan; Meyer, Anne S.

    2015-01-01

    of the integrated system. Full conversion of glucose to gluconic acid assisted by glucose oxidase (GOD) could be achieved by coupling a parallel reaction catalyzed by catalase (CAT), where H2O2 (GOD-inhibitor formed in the first reaction) was decomposed to water and oxygen. GOD has a high oxygen...

  6. Accuracy of Corneal Thickness by Swept-Source Optical Coherence Tomography and Scheimpflug Camera in Virgin and Treated Fuchs Endothelial Dystrophy.

    Science.gov (United States)

    Arnalich-Montiel, Francisco; Ortiz-Toquero, Sara; Auladell, Clara; Couceiro, Ana

    2018-06-01

    To assess intraobserver repeatability, intersession reproducibility, and agreement of swept-source Fourier-domain optical coherence tomography (SS-OCT) and the Scheimpflug camera in measuring corneal thickness in virgin and grafted eyes with Fuchs endothelial corneal dystrophy (FECD). Thirty-six control eyes, 35 FECD eyes, 30 FECD with corneal edema eyes, 25 Descemet stripping automated endothelial keratoplasty (DSAEK) eyes, and 29 Descemet membrane endothelial keratoplasty (DMEK) eyes were included. The apical center, pupillary center, and thinnest corneal thickness were determined in 3 consecutive images and repeated 2 weeks later. Repeatability and reproducibility coefficients, intraclass correlation coefficients, and 95% limits of agreement (LOA) between measurements were calculated. Agreement between devices was assessed using Bland-Altman analysis. Corneal thickness measurements were highly reproducible and repeatable with both systems. SS-OCT showed better repeatability in all corneal locations in the normal, FECD, FECD with edema, DSAEK, and DMEK groups (coefficient of variation ≤0.60%, ≤0.36%, ≤0.43%, ≤1.09%, and ≤0.48%, respectively) than the Scheimpflug (coefficient of variation ≤1.15%, ≤0.92%, ≤1.10%, ≤1.25%, and ≤1.14%, respectively). Between-session 95% LOA for SS-OCT was less than 3% for all groups except for the FECD with edema group, being almost double using the Scheimpflug camera. Differences between instruments were statistically significant in all groups and locations (P group (P ≤ 0.51); however, SS-OCT underestimated all measurements. SS-OCT provides better reproducible and repeatable measurements of corneal thickness than those obtained with the Scheimpflug camera in patients with FECD or an endothelial transplant. Variations between examinations higher than the 95% LOA observed in our study should raise awareness of changes in the endothelial function.

  7. Suppression of renal fibrosis by galectin-1 in high glucose-treated renal epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Kazuhiro, E-mail: kaokano@kc.twmu.ac.jp; Tsuruta, Yuki; Yamashita, Tetsuri; Takano, Mari; Echida, Yoshihisa; Nitta, Kosaku

    2010-11-15

    Diabetic nephropathy is the most common cause of chronic kidney disease. We investigated the ability of intracellular galectin-1 (Gal-1), a prototype of endogenous lectin, to prevent renal fibrosis by regulating cell signaling under a high glucose (HG) condition. We demonstrated that overexpression of Gal-1 reduces type I collagen (COL1) expression and transcription in human renal epithelial cells under HG conditions and transforming growth factor-{beta}1 (TGF-{beta}1) stimulation. Matrix metalloproteinase 1 (MMP1) is stimulated by Gal-1. HG conditions and TGF-{beta}1 treatment augment expression and nuclear translocation of Gal-1. In contrast, targeted inhibition of Gal-1 expression reduces COL1 expression and increases MMP1 expression. The Smad3 signaling pathway is inhibited, whereas two mitogen-activated protein kinase (MAPK) pathways, p38 and extracellular signal-regulated kinase (ERK), are activated by Gal-1, indicating that Gal-1 regulates these signaling pathways in COL1 production. Using specific inhibitors of Smad3, ERK, and p38 MAPK, we showed that ERK MAPK activated by Gal-1 plays an inhibitory role in COL1 transcription and that activation of the p38 MAPK pathway by Gal-1 plays a negative role in MMP1 production. Taken together, two MAPK pathways are stimulated by increasing levels of Gal-1 in the HG condition, leading to suppression of COL1 expression and increase of MMP1 expression.

  8. Protective effects of antioxidants on high Glucose-induced malfunctions in human glomerular mesangial cells

    Directory of Open Access Journals (Sweden)

    Hosseini R

    2000-08-01

    Full Text Available Altered functions of mesangial cells induced by high glucose concentrations are thought to play an important role in the pathogenesis of diabetic nephropathy. We therefore investigated the effect of high glucose (39.2 mM alone and in combination with taurine (500 µM or vitamin E (100 µM in serum free medium (RPMI 1640 on the proliferative growth response and turnover of type IV collagen by human glomerular mesangial cells (GMC. The results showed that the high glucose level decreases the proliferation of the GMC which is reversed by taurine and vitamin E. In order to control the osmotic effects of high glucose, the GMC were also cultured in the presence of manitol. Manitol had no effect on the proliferation of GMC. Furthermore, the results showed that addition of vitamin E or taurine to media containing high glucose could reverse and normalize the collagen turn-over by the cultured mesangial cells. These results suggest that taurie and vitamin E may function as endogenous agents in the kidney to limit the development of glomerulosclerosis in diabetic renal disease.

  9. Soluble intercellular adhesion molecule-1 and interleukin-6 levels reflect endothelial dysfunction in patients with primary hypercholesterolaemia treated with atorvastatin.

    Science.gov (United States)

    Nawawi, H; Osman, N S; Annuar, R; Khalid, B A K; Yusoff, K

    2003-08-01

    Adhesion molecules and cytokines are involved in the pathogenesis of intimal injury in atherosclerosis but their relationship with endothelial function remains unclear. The objectives of this study were to examine the effects of atorvastatin on soluble adhesion molecules, interleukin-6 (IL-6) and brachial artery endothelial-dependent flow mediated dilatation (FMD) in patients with familial (FH) and non-familial hypercholesterolaemia (NFH). A total of 74 patients (27 FH and 47 NFH) were recruited. Fasting lipid profiles, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular-cellular adhesion molecule-1 (sVCAM-1), E-selectin, IL-6 and FMD were measured at baseline, 2 weeks, 3 and 9 months post-atorvastatin treatment (FH--80 mg/day, NFH--10 mg/day). In both groups, compared to baseline, sICAM-1 levels were significantly reduced at 2 weeks, further reduced at 3 months and maintained at 9 months (P<0.0001). The IL-6 levels were significantly reduced at 3 months and 9 months compared to baseline for FH (P<0.005) and NFH (P<0.0001). In both groups, the FMD at 2 weeks was higher than baseline (P<0.005), with progressive improvement up to 9 months. FMD was negatively correlated with sICAM-1 and IL-6. In conclusion, both low and high doses of atorvastatin lead to early progressive improvement in endothelial function in patients with primary hypercholesterolaemia. sICAM-1 and IL-6 levels reflect endothelial dysfunction in these patients.

  10. Vildagliptin stimulates endothelial cell network formation and ischemia-induced revascularization via an endothelial nitric-oxide synthase-dependent mechanism.

    Science.gov (United States)

    Ishii, Masakazu; Shibata, Rei; Kondo, Kazuhisa; Kambara, Takahiro; Shimizu, Yuuki; Tanigawa, Tohru; Bando, Yasuko K; Nishimura, Masahiro; Ouchi, Noriyuki; Murohara, Toyoaki

    2014-09-26

    Dipeptidyl peptidase-4 inhibitors are known to lower glucose levels and are also beneficial in the management of cardiovascular disease. Here, we investigated whether a dipeptidyl peptidase-4 inhibitor, vildagliptin, modulates endothelial cell network formation and revascularization processes in vitro and in vivo. Treatment with vildagliptin enhanced blood flow recovery and capillary density in the ischemic limbs of wild-type mice, with accompanying increases in phosphorylation of Akt and endothelial nitric-oxide synthase (eNOS). In contrast to wild-type mice, treatment with vildagliptin did not improve blood flow in ischemic muscles of eNOS-deficient mice. Treatment with vildagliptin increased the levels of glucagon-like peptide-1 (GLP-1) and adiponectin, which have protective effects on the vasculature. Both vildagliptin and GLP-1 increased the differentiation of cultured human umbilical vein endothelial cells (HUVECs) into vascular-like structures, although vildagliptin was less effective than GLP-1. GLP-1 and vildagliptin also stimulated the phosphorylation of Akt and eNOS in HUVECs. Pretreatment with a PI3 kinase or NOS inhibitor blocked the stimulatory effects of both vildagliptin and GLP-1 on HUVEC differentiation. Furthermore, treatment with vildagliptin only partially increased the limb flow of ischemic muscle in adiponectin-deficient mice in vivo. GLP-1, but not vildagliptin, significantly increased adiponectin expression in differentiated 3T3-L1 adipocytes in vitro. These data indicate that vildagliptin promotes endothelial cell function via eNOS signaling, an effect that may be mediated by both GLP-1-dependent and GLP-1-independent mechanisms. The beneficial activity of GLP-1 for revascularization may also be partially mediated by its ability to increase adiponectin production. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Longitudinal PET evaluation of cerebral glucose metabolism in rivastigmine treated patients with mild Alzheimer's disease

    International Nuclear Information System (INIS)

    Stefanova, E.; Forsberg, A.; Wall, A.; Nilsson, A.; Langstroem, B.; Almkvist, O.; Nordberg, A.

    2006-01-01

    In this study 11 patients with mild Alzheimer's disease (AD) were treated with the cholinesterase inhibitor rivastigmine (mean dose 8.6 ± 1.3 mg) for 12 months and underwent positron emission tomography (PET) studies of cerebral glucose metabolism (CMRglc) and neuropsychological testing at baseline and after 12 months. An untreated group of 10 AD patients served as control group. While the untreated AD patients showed a significant decline of CMRglc in the temporo-parietal and frontal cortical regions after 12 months follow-up the rivastigmine-treated patients showed no decline in CMRglc in corresponding cortical brain regions. Furthermore, a significant dose-related increase in CMRglc was recorded in the right frontal association region after 12 months rivastigmine treatment. A positive correlation was observed between changes in CMRglc and several cognitive tests in patients receiving higher doses (10.5-12 mg) of rivastigmine. These results suggest a stabilization effect of rivastigmine on CMRglc in mild AD patients receiving long-term rivastigmine treatment. (author)

  12. Flavonoid-Rich Apple Improves Endothelial Function in Individuals at Risk for Cardiovascular Disease: A Randomized Controlled Clinical Trial.

    Science.gov (United States)

    Bondonno, Nicola P; Bondonno, Catherine P; Blekkenhorst, Lauren C; Considine, Michael J; Maghzal, Ghassan; Stocker, Roland; Woodman, Richard J; Ward, Natalie C; Hodgson, Jonathan M; Croft, Kevin D

    2018-02-01

    The cardioprotective effects of apples are primarily attributed to flavonoids, found predominantly in the skin. This study aimed to determine if acute and/or chronic (4 weeks) ingestion of flavonoid-rich apples improves endothelial function, blood pressure (BP), and arterial stiffness in individuals at risk for cardiovascular diseases (CVD). In this randomized, controlled cross-over trial, acute and 4 week intake of apple with skin (high flavonoid apple, HFA) is compared to intake of apple flesh only (low flavonoid apple, LFA) in 30 participants. The primary outcome is endothelial function assessed using flow-mediated dilation (FMD) of the brachial artery, while main secondary outcomes are 24 h ambulatory BP and arterial stiffness. Other outcomes include fasting serum glucose and lipoprotein profile, plasma heme oxygenase-1 (Hmox-1), F 2 -isoprostanes, flavonoid metabolites, and plasma and salivary nitrate (NO 3 - ) and nitrite (NO 2 - ) concentrations. Compared to LFA control, the HFA results in a significant increase in FMD acutely (0.8%, p flavonoid metabolites (p effect of apple skin on endothelial function, both acutely and chronically. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. High pressure HC1 conversion of cellulose to glucose

    Energy Technology Data Exchange (ETDEWEB)

    Antonoplis, Robert Alexander [Univ. of California, Berkeley, CA (United States); Blanch, Harvey W. [Univ. of California, Berkeley, CA (United States); Wilke, Charles R. [Univ. of California, Berkeley, CA (United States)

    1981-08-01

    The production of ethanol from glucose by means of fermentation represents a potential long-range alternative to oil for use as a transportation fuel. Today's rising oil prices and the dwindling world supply of oil have made other fuels, such as ethanol, attractive alternatives. It has been shown that automobiles can operate, with minor alterations, on a 10% ethanol-gasoline mixture popularly known as gasohol. Wood has long been known as a potential source of glucose. Glucose may be obtained from wood following acid hydrolysis. In this research, it was found that saturating wood particles with HCl gas under pressure was an effective pretreatment before subjecting the wood to dilute acid hydrolysis. The pretreatment is necessary because of the tight lattice structure of cellulose, which inhibits dilute acid hydrolysis. HCl gas makes the cellulose more susceptible to hydrolysis and the glucose yield is doubled when dilute acid hydrolysis is preceded by HCl saturation at high pressure. The saturation was most effectively performed in a fluidized bed reactor, with pure HCl gas fluidizing equal volumes of ground wood and inert particles. The fluidized bed effectively dissipated the large amount of heat released upon HCl absorption into the wood. Batch reaction times of one hour at 314.7 p.s.i.a. gave glucose yields of 80% and xylose yields of 95% after dilute acid hydrolysis. A non-catalytic gas-solid reaction model, with gas diffusing through the solid limiting the reaction rate, was found to describe the HCl-wood reaction in the fluidized bed. HCl was found to form a stable adduct with the lignin residue in the wood, in a ratio of 3.33 moles per mole of lignin monomer. This resulted in a loss of 0.1453 lb. of HCl per pound of wood. The adduct was broken upon the addition of water. A process design and economic evaluation for a plant to produce 214 tons per day of glucose from air-dried ground Populus tristi gave an estimated glucose cost of 15.14 cents per pound

  14. Glucose-installed, SPIO-loaded PEG- b-PCL micelles as MR contrast agents to target prostate cancer cells

    Science.gov (United States)

    Theerasilp, Man; Sunintaboon, Panya; Sungkarat, Witaya; Nasongkla, Norased

    2017-11-01

    Polymeric micelles of poly(ethylene glycol)- block-poly(ɛ-caprolactone) bearing glucose analog encapsulated with superparamagnetic iron oxide nanoparticles (Glu-SPIO micelles) were synthesized as an MRI contrast agent to target cancer cells based on high-glucose metabolism. Compared to SPIO micelles (non-targeting SPIO micelles), Glu-SPIO micelles demonstrated higher toxicity to human prostate cancer cell lines (PC-3) at high concentration. Atomic absorption spectroscopy was used to determine the amount of iron in cells. It was found that the iron in cancer cells treated by Glu-SPIO micelles were 27-fold higher than cancer cells treated by SPIO micelles at the iron concentration of 25 ppm and fivefold at the iron concentration of 100 ppm. To implement Glu-SPIO micelles as a MR contrast agent, the 3-T clinical MRI was applied to determine transverse relaxivities ( r 2*) and relaxation rate (1/ T 2*) values. In vitro MRI showed different MRI signal from cancer cells after cellular uptake of SPIO micelles and Glu-SPIO micelles. Glu-SPIO micelles was highly sensitive with the r 2* in agarose gel at 155 mM-1 s-1. Moreover, the higher 1/ T 2* value was found for cancer cells treated with Glu-SPIO micelles. These results supported that glucose ligand increased the cellular uptake of micelles by PC-3 cells with over-expressing glucose transporter on the cell membrane. Thus, glucose can be used as a small molecule ligand for targeting prostate cancer cells overexpressing glucose transporter.

  15. Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets.

    Science.gov (United States)

    Lee, Yun Jung; Choi, Deok Ho; Cho, Guk Hyun; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2012-08-06

    Arctium lappa L. (Asteraceae), burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL) seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD). EAL-I (100 mg·kg-1/day), EAL-II (200 mg·kg-1/day), and fluvastatin (3 mg·kg-1/day) groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks. Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL) in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh)-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP) and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP)-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model. The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.

  16. Arctium lappa ameliorates endothelial dysfunction in rats fed with high fat/cholesterol diets

    Directory of Open Access Journals (Sweden)

    Lee Yun

    2012-08-01

    Full Text Available Abstract Background Arctium lappa L. (Asteraceae, burdock, is a medicinal plant that is popularly used for treating hypertension, gout, hepatitis, and other inflammatory disorders. This study was performed to test the effect of ethanol extract of Arctium lappa L. (EAL seeds on vascular reactivity and inflammatory factors in rats fed a high fat/cholesterol diet (HFCD. Method EAL-I (100 mg·kg−1/day, EAL-II (200 mg·kg−1/day, and fluvastatin (3 mg·kg−1/day groups initially received HFCD alone for 8 weeks, with EAL supplementation provided during the final 6 weeks. Results Treatment with low or high doses of EAL markedly attenuated plasma levels of triglycerides and augmented plasma levels of high-density lipoprotein (HDL in HFCD-fed rats. Chronic treatment with EAL markedly reduced impairments of acetylcholine (ACh-induced relaxation of aortic rings. Furthermore, chronic treatment with EAL significantly lowered systolic blood pressure (SBP and maintained smooth and flexible intimal endothelial layers in HFCD-fed rats. Chronic treatment with EAL suppressed upregulation of intercellular adhesion molecule (ICAM-1, vascular cell adhesion molecule (VCAM-1, and E-selectin in the aorta. Chronic treatment with EAL also suppressed increases in matrix metalloproteinase (MMP-2 expression. These results suggested that EAL can inhibit HFCD-induced vascular inflammation in the rat model. Conclusion The present study provides evidence that EAL ameliorates HFCD-induced vascular dysfunction through protection of vascular relaxation and suppression of vascular inflammation.

  17. Microsporidial infection masquerading as graft rejection post-Descemet's stripping automated endothelial keratoplasty

    Directory of Open Access Journals (Sweden)

    Lumbini Devi

    2017-01-01

    Full Text Available A 51-year-old immunocompetent male with a history of Fuchs' endothelial dystrophy and immature cataract who underwent Descemet's stripping automated endothelial keratoplasty with intraocular lens implantation in both eyes presented with redness and defective vision of 1-day duration in his left eye. Slit lamp examination revealed coarse superficial punctate lesions with graft edema. He was diagnosed with acute graft rejection and treated with topical steroids. Two days later, symptoms worsened in his left eye with the involvement of his right eye showing a similar clinical picture. An infectious etiology was suspected and in vivo confocal microscopy ordered, which revealed hyperreflective dots, highly suggestive of microsporidial spores. The patient was prescribed topical fluconazole 0.3% in both eyes. This unique presentation of bilateral graft edema following microsporidial keratoconjunctivitis in postgraft patients requires a high index of suspicion as it can be easily be mistaken for and mismanaged as acute graft rejection.

  18. NFAT2 mediates high glucose-induced glomerular podocyte apoptosis through increased Bax expression

    International Nuclear Information System (INIS)

    Li, Ruizhao; Zhang, Li; Shi, Wei; Zhang, Bin; Liang, Xinling; Liu, Shuangxin; Wang, Wenjian

    2013-01-01

    Background: Hyperglycemia promotes podocyte apoptosis and plays a key role in the pathogenesis of diabetic nephropathy. However, the mechanisms that mediate hyperglycemia-induced podocyte apoptosis is still far from being fully understood. Recent studies reported that high glucose activate nuclear factor of activated T cells (NFAT) in vascular smooth muscle or pancreatic β-cells. Here, we sought to determine if hyperglycemia activates NFAT2 in cultured podocyte and whether this leads to podocyte apoptosis. Meanwhile, we also further explore the mechanisms of NFAT2 activation and NFAT2 mediates high glucose-induced podocyte apoptosis. Methods: Immortalized mouse podocytes were cultured in media containing normal glucose (NG), or high glucose (HG) or HG plus cyclosporine A (a pharmacological inhibitor of calcinerin) or 11R-VIVIT (a special inhibitor of NFAT2). The activation of NFAT2 in podocytes was detected by western blotting and immunofluorescence assay. The role of NFAT2 in hyperglycemia-induced podocyte apoptosis was further evaluated by observing the inhibition of NFAT2 activation by 11R-VIVIT using flow cytometer. Intracellular Ca 2+ was monitored in HG-treated podcocytes using Fluo-3/AM. The mRNA and protein expression of apoptosis gene Bax were measured by real time-qPCR and western blotting. Results: HG stimulation activated NFAT2 in a time- and dose-dependent manner in cultured podocytes. Pretreatment with cyclosporine A (500 nM) or 11R-VIVIT (100 nM) completely blocked NFAT2 nuclear accumulation. Meanwhile, the apoptosis effects induced by HG were also abrogated by concomitant treatment with 11R-VIVIT in cultured podocytes. We further found that HG also increased [Ca 2+ ]i, leading to activation of calcineurin, and subsequent increased nuclear accumulation of NFAT2 and Bax expression in cultured podocytes. Conclusion: Our results identify a new finding that HG-induced podocyte apoptosis is mediated by calcineurin/NFAT2/Bax signaling pathway, which may

  19. NFAT2 mediates high glucose-induced glomerular podocyte apoptosis through increased Bax expression

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ruizhao, E-mail: liruizhao1979@126.com [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Zhang, Li, E-mail: Zhanglichangde@163.com [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Southern Medical University, Guangzhou, Guangdong (China); Shi, Wei, E-mail: shiwei.gd@139.com [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Zhang, Bin, E-mail: zhangbinyes@yahoo.com.cn [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Liang, Xinling, E-mail: xinlingliang@yahoo.com [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Liu, Shuangxin, E-mail: mplsxi@yahoo.com.cn [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China); Wang, Wenjian, E-mail: wwjph@yahoo.com [Department of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, 106 Zhongshan No. 2 Road, Guangzhou, 510080 (China)

    2013-04-15

    Background: Hyperglycemia promotes podocyte apoptosis and plays a key role in the pathogenesis of diabetic nephropathy. However, the mechanisms that mediate hyperglycemia-induced podocyte apoptosis is still far from being fully understood. Recent studies reported that high glucose activate nuclear factor of activated T cells (NFAT) in vascular smooth muscle or pancreatic β-cells. Here, we sought to determine if hyperglycemia activates NFAT2 in cultured podocyte and whether this leads to podocyte apoptosis. Meanwhile, we also further explore the mechanisms of NFAT2 activation and NFAT2 mediates high glucose-induced podocyte apoptosis. Methods: Immortalized mouse podocytes were cultured in media containing normal glucose (NG), or high glucose (HG) or HG plus cyclosporine A (a pharmacological inhibitor of calcinerin) or 11R-VIVIT (a special inhibitor of NFAT2). The activation of NFAT2 in podocytes was detected by western blotting and immunofluorescence assay. The role of NFAT2 in hyperglycemia-induced podocyte apoptosis was further evaluated by observing the inhibition of NFAT2 activation by 11R-VIVIT using flow cytometer. Intracellular Ca{sup 2+} was monitored in HG-treated podcocytes using Fluo-3/AM. The mRNA and protein expression of apoptosis gene Bax were measured by real time-qPCR and western blotting. Results: HG stimulation activated NFAT2 in a time- and dose-dependent manner in cultured podocytes. Pretreatment with cyclosporine A (500 nM) or 11R-VIVIT (100 nM) completely blocked NFAT2 nuclear accumulation. Meanwhile, the apoptosis effects induced by HG were also abrogated by concomitant treatment with 11R-VIVIT in cultured podocytes. We further found that HG also increased [Ca{sup 2+}]i, leading to activation of calcineurin, and subsequent increased nuclear accumulation of NFAT2 and Bax expression in cultured podocytes. Conclusion: Our results identify a new finding that HG-induced podocyte apoptosis is mediated by calcineurin/NFAT2/Bax signaling pathway

  20. Sildenafil restores endothelial function in the apolipoprotein E knockout mouse

    Directory of Open Access Journals (Sweden)

    Balarini Camille M

    2013-01-01

    Full Text Available Abstract Background Atherosclerosis is an inflammatory process of the arterial walls and is initiated by endothelial dysfunction accompanied by an imbalance in the production of reactive oxygen species (ROS and nitric oxide (NO. Sildenafil, a selective phosphodiesterase-5 (PDE5 inhibitor used for erectile dysfunction, exerts its cardiovascular effects by enhancing the effects of NO. The aim of this study was to investigate the influence of sildenafil on endothelial function and atherosclerosis progression in apolipoprotein E knockout (apoE−/− mice. Methods ApoE−/− mice treated with sildenafil (Viagra®, 40 mg/kg/day, for 3 weeks, by oral gavage were compared to the untreated apoE−/− and the wild-type (WT mice. Aortic rings were used to evaluate the relaxation responses to acetylcholine (ACh in all of the groups. In a separate set of experiments, the roles of NO and ROS in the relaxation response to ACh were evaluated by incubating the aortic rings with L-NAME (NO synthase inhibitor or apocynin (NADPH oxidase inhibitor. In addition, the atherosclerotic lesions were quantified and superoxide production was assessed. Results Sildenafil restored the vasodilator response to acetylcholine (ACh in the aortic rings of the apoE−/− mice. Treatment with L-NAME abolished the vasodilator responses to ACh in all three groups of mice and revealed an augmented participation of NO in the endothelium-dependent vasodilation in the sildenafil-treated animals. The normalized endothelial function in sildenafil-treated apoE−/− mice was unaffected by apocynin highlighting the low levels of ROS production in these animals. Moreover, morphological analysis showed that sildenafil treatment caused approximately a 40% decrease in plaque deposition in the aorta. Conclusion This is the first study demonstrating the beneficial effects of chronic treatment with sildenafil on endothelial dysfunction and atherosclerosis in a model of spontaneous

  1. Flash Glucose-Sensing Technology as a Replacement for Blood Glucose Monitoring for the Management of Insulin-Treated Type 2 Diabetes: a Multicenter, Open-Label Randomized Controlled Trial.

    Science.gov (United States)

    Haak, Thomas; Hanaire, Hélène; Ajjan, Ramzi; Hermanns, Norbert; Riveline, Jean-Pierre; Rayman, Gerry

    2017-02-01

    Glycemic control in participants with insulin-treated diabetes remains challenging. We assessed safety and efficacy of new flash glucose-sensing technology to replace self-monitoring of blood glucose (SMBG). This open-label randomized controlled study (ClinicalTrials.gov, NCT02082184) enrolled adults with type 2 diabetes on intensive insulin therapy from 26 European diabetes centers. Following 2 weeks of blinded sensor wear, 2:1 (intervention/control) randomization (centrally, using biased-coin minimization dependant on study center and insulin administration) was to control (SMBG) or intervention (glucose-sensing technology). Participants and investigators were not masked to group allocation. Primary outcome was difference in HbA1c at 6 months in the full analysis set. Prespecified secondary outcomes included time in hypoglycemia, effect of age, and patient satisfaction. Participants (n = 224) were randomized (149 intervention, 75 controls). At 6 months, there was no difference in the change in HbA1c between intervention and controls: -3.1 ± 0.75 mmol/mol, [-0.29 ± 0.07% (mean ± SE)] and -3.4 ± 1.04 mmol/mol (-0.31 ± 0.09%) respectively; p = 0.8222. A difference was detected in participants aged glucose-sensing technology use in type 2 diabetes with intensive insulin therapy results in no difference in HbA1c change and reduced hypoglycemia, thus offering a safe, effective replacement for SMBG. ClinicalTrials.gov identifier: NCT02082184. Abbott Diabetes Care.

  2. The protective effect of magnesium lithospermate B against glucose-induced intracellular oxidative damage

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Jian [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Xiangya School of Medicine, Changsha 410078 (China); Ren, Xian [Shanghai Green Valley Pharmaceutical Co., Ltd., Shanghai 201304 (China); Hou, Rui-ying; Dai, Xing-ping [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Xiangya School of Medicine, Changsha 410078 (China); Zhao, Ying-chun [Laboratories of Functional Genomics and Proteomics, Creighton University Medical Center, Omaha, NE 68131 (United States); Xu, Xiao-jing; Zhang, Wei; Zhou, Gan; Zhou, Hong-hao [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Xiangya School of Medicine, Changsha 410078 (China); Liu, Zhao-qian, E-mail: liuzhaoqian63@126.com [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Xiangya School of Medicine, Changsha 410078 (China)

    2011-07-22

    Highlights: {yields} LAB reduced the ROS production in HEK293T cells cultured under oxidative stress. High dose of glucose enhanced the expression of HO-1 mRNA and HO-1 protein in a time-dependent manner. {yields} LAB enhanced the expression of HO-1 mRNA and HO-1 protein in a dose-dependent manner treated with high dose of glucose. {yields} LAB plays an important role against glucose-induced intracellular oxidative damage. {yields} The enhanced expression of HO-1 mRNA and HO-1 protein caused by LAB is regulated via Nrf2 signal pathway. -- Abstract: Objectives: To investigate the effects of magnesium lithospermate B (LAB) on intracellular reactive oxygen species (ROS) production induced by high dose of glucose or H{sub 2}O{sub 2}, we explored the influences of LAB on the expression of heme oxygenase-1 (HO-1) and nuclear factor E2-related factor-2 (Nrf2) in HEK293T cells after treatment with high dose of glucose. Materials and methods: The total nuclear proteins in HEK293T cells were extracted with Cytoplasmic Protein Extraction Kit. The ROS level was determined by flow cytometry. The mRNA and protein expression of HO-1 and Nrf2 were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot. Results: LAB reduced the ROS production in HEK293T cells cultured under oxidative stress. High dose of glucose enhanced the expression of HO-1 mRNA and HO-1 protein in a time-dependent manner. LAB enhanced the expression of HO-1 mRNA and HO-1 protein in a dose-dependent manner treated with high dose of glucose. The amount of Nrf2 translocation was enhanced after cells were pretreated with 50 {mu}mol/L or 100 {mu}mol/L LAB. Silencing of Nrf2 gene eliminated the enhanced expression of HO-1 protein induced by high dose of glucose plus LAB. Conclusions: LAB plays an important role against glucose-induced intracellular oxidative damage. The enhanced expression of HO-1 mRNA and HO-1 protein caused by LAB is regulated via Nrf2 signal pathway.

  3. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Complications Neuropathy Foot Complications DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & Care Blood Glucose Testing Medication Doctors, Nurses & More ...

  4. Caffeoyl glucosides from Nandina domestica inhibit LPS-induced endothelial inflammatory responses.

    Science.gov (United States)

    Kulkarni, Roshan R; Lee, Wonhwa; Jang, Tae Su; Lee, JungIn; Kwak, Soyoung; Park, Mi Seon; Lee, Hyun-Shik; Bae, Jong-Sup; Na, MinKyun

    2015-11-15

    Endothelial dysfunction is a key pathological feature of many inflammatory diseases, including sepsis. In the present study, a new caffeoyl glucoside (1) and two known caffeoylated compounds (2 and 3) were isolated from the fruits of Nandina domestica Thunb. (Berberidaceae). The compounds were investigated for their effects against lipopolysaccharide (LPS)-mediated endothelial inflammatory responses. At 20 μM, 1 and 2 inhibited LPS-induced hyperpermeability, adhesion, and migration of leukocytes across a human endothelial cell monolayer in a dose-dependent manner suggesting that 1 and 2 may serve as potential scaffolds for the development of therapeutic agents to treat vascular inflammatory disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. The Deletion of Endothelial Sodium Channel α (αENaC Impairs Endothelium-Dependent Vasodilation and Endothelial Barrier Integrity in Endotoxemia in Vivo

    Directory of Open Access Journals (Sweden)

    Magdalena Sternak

    2018-04-01

    Full Text Available The role of epithelial sodium channel (ENaC activity in the regulation of endothelial function is not clear. Here, we analyze the role of ENaC in the regulation of endothelium-dependent vasodilation and endothelial permeability in vivo in mice with conditional αENaC subunit gene inactivation in the endothelium (endo-αENaCKO mice using unique MRI-based analysis of acetylcholine-, flow-mediated dilation and vascular permeability. Mice were challenged or not with lipopolysaccharide (LPS, from Salmonella typhosa, 10 mg/kg, i.p.. In addition, changes in vascular permeability in ex vivo organs were analyzed by Evans Blue assay, while changes in vascular permeability in perfused mesenteric artery were determined by a FITC-dextran-based assay. In basal conditions, Ach-induced response was completely lost, flow-induced vasodilation was inhibited approximately by half but endothelial permeability was not changed in endo-αENaCKO vs. control mice. In LPS-treated mice, both Ach- and flow-induced vasodilation was more severely impaired in endo-αENaCKO vs. control mice. There was also a dramatic increase in permeability in lungs, brain and isolated vessels as evidenced by in vivo and ex vivo analysis in endotoxemic endo-αENaCKO vs. control mice. The impaired endothelial function in endotoxemia in endo-αENaCKO was associated with a decrease of lectin and CD31 endothelial staining in the lung as compared with control mice. In conclusion, the activity of endothelial ENaC in vivo contributes to endothelial-dependent vasodilation in the physiological conditions and the preservation of endothelial barrier integrity in endotoxemia.

  6. Impaired Glucose Tolerance in Healthy Men Treated with St. John's Wort

    DEFF Research Database (Denmark)

    Stage, Tore Bjerregaard; Damkier, Per; Christensen, Mette Marie Hougaard

    2016-01-01

    The purpose of this study was to examine if the over-the-counter herbal medicinal plant St. John's wort affects glucose tolerance in healthy men. To do this, we included 10 healthy men who were examined by a 2-hr oral glucose tolerance test on three occasions; A: Baseline, B: After 21 days...

  7. Endothelial lipase is highly expressed in macrophages in advanced human atherosclerotic lesions

    DEFF Research Database (Denmark)

    Bartels, Emil D; Nielsen, John E; Lindegaard, Marie Louise Skakkebæk

    2007-01-01

    Endothelial lipase (EL) is expressed in endothelial cells, and affects plasma lipoprotein metabolism by hydrolyzing phospholipids in HDL. To determine the cellular expression of EL mRNA and protein in human atherosclerotic lesions, we performed in situ hybridization and immunohistochemical studies...

  8. Body mass index is associated with microvascular endothelial dysfunction in patients with treated metabolic risk factors and suspected coronary artery disease

    NARCIS (Netherlands)

    D.J. Van Der Heijden (Dirk J.); M.A.H. van Leeuwen (Maarten); G.N. Janssens (Gladys N.); M.J. Lenzen (Mattie); P.M. van de Ven (Peter); E.C. Eringa (Etto ); N. van Royen (Niels)

    2017-01-01

    textabstractBackground--Obesity is key feature of the metabolic syndrome and is associated with high cardiovascular morbidity and mortality. Obesity is associated with macrovascular endothelial dysfunction, a determinant of outcome in patients with coronary artery disease. Here, we compared the

  9. Histones Induce the Procoagulant Phenotype of Endothelial Cells through Tissue Factor Up-Regulation and Thrombomodulin Down-Regulation.

    Science.gov (United States)

    Kim, Ji Eun; Yoo, Hyun Ju; Gu, Ja Yoon; Kim, Hyun Kyung

    2016-01-01

    The high circulating levels of histones found in various thrombotic diseases may compromise the anticoagulant barrier of endothelial cells. We determined how histones affect endothelial procoagulant tissue factor (TF) and anticoagulant thrombomodulin (TM). Surface antigens, soluble forms, and mRNA levels of TF and TM were measured by flow cytometry, ELISA, and real-time RT-PCR, respectively. TF and TM activity were measured using procoagulant activity, thrombin generation, or chromogenic assays. Involvement of the toll-like receptor (TLR) was assessed using the neutralizing antibodies. Histones dose-dependently induced surface antigens, activity and mRNA levels of endothelial TF. Histone-treated endothelial cells significantly shortened the lag time and enhanced the endogenous thrombin potential of normal plasma, which was normalized by a TF neutralizing antibody. Histones induced phosphatidylserine and protein-disulfide isomerase expression in endothelial cells. Histones also reduced the surface antigen, activity, and mRNA levels of endothelial TM. Polysialic acid and heparin reversed the histone-induced TF up-regulation and TM down-regulation. Activated protein C did not affect the TF up-regulation, but interrupted TM down-regulation. TLR2, and TLR4 inhibitors partially blocked the TF up-regulation. Histones induced the endothelial procoagulant phenotype through TF up-regulation and TM down-regulation. The effects of histones were partly mediated by TLR2, TLR4. Strategies to inhibit the harmful effects of histones in endothelial cells may be required in order to prevent a thrombotic environment.

  10. Ionizing radiation activates vascular endothelial growth factor-A transcription in human umbilical vein endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyounji; Kim, Kwang Seok; Jeong, Jae Hoon; Lim, Young Bin [Radiation Cancer Biology Team, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2016-12-15

    Vascular endothelial growth factor (VEGF) is an essential paracrine factor for developmental and pathological angiogenesis. VEGF also exerts its effects in an autocrine manner in VEGF-producing cells. For instance, autocrine VEGF signaling occurs in tumor cells and contributes to key aspects of tumorigenesis, such as in the function of cancer stem cells and tumor initiation, which are independent of angiogenesis. In addition to tumors cells, non-transformed cells also express VEGF. For example, a VEGF dependent intracellular autocrine mechanism is crucial for the survival of hematopoietic stem cells and hematopoiesis. Stereotactic body radiation therapy (SBRT) is a novel treatment modality for early primary cancer and oligometastatic disease. SBRT delivers high-dose hypofractionated radiation, such as 20-60 Gy, to tumors in a single fraction or 2-5 fractions. As VEGF is a critical regulator of functional integrity and viability of vascular endothelial cells, we examined whether high-dose irradiation alters VEGF signaling by measuring the expression levels of VEGFA transcript. It is generally believed that endothelial cells do not produce VEGF in response to radiation. In present study, however, we provide the first demonstration of transcriptional regulation of VEGFA in human vascular endothelial cells by IR treatment. Irradiation with doses higher than 10 Gy in a single exposure triggers up-regulation of VEGFA transcription within 2 hours in HUVECs, whereas irradiation with 10 Gy does not alter VEGFA levels. Our data have shown that high-dose irradiation triggers immediate transactivation of VEGFA in human vascular endothelial cells.

  11. Glucose kinetics in gluconeogenesis-inhibited rats during rest and exercise

    International Nuclear Information System (INIS)

    Turcotte, L.P.; Rovner, A.S.; Roark, R.R.; Brooks, G.A.

    1990-01-01

    To evaluate the role played by gluconeogenesis in blood glucose homeostasis, female Sprague-Dawley rats were injected with mercaptopicolinic acid (MPA), a gluconeogenic inhibitor. Glucose kinetics were assessed by primed, continuous infusion of [U-14C]- and [6(-3)H]glucose via an indwelling jugular catheter at rest and during submaximal exercise at 13.4 m/min on level grade. Blood samples were taken from carotid catheters and analyzed for glucose and lactate concentrations and specific activities. Tissue glycogen samples were obtained from rats after exercise as well as from unexercised animals. When compared with the sham-injected animals, MPA-treated animals had 22% lower (5.92 +/- 0.36 vs. 7.62 +/- 0.21 mM) and 44% higher (1.90 +/- 0.11 vs. 1.32 +/- 0.09 mM) resting arterial glucose and lactate concentrations, respectively. Resting glucose appearance (Ra) rates were 20% lower in the MPA-treated animals (57.2 +/- 7.5 mumol.kg-1.min-1) than in the sham-injected animals (71.1 +/- 12.1 mumol.kg-1.min-1). During exercise, Ra increased to 174.7 +/- 32.8 mumol.kg-1.min-1 in sham-injected animals. In the MPA-treated animals, there was a 35% increase during the first 15 min of exercise, followed by a decrease to the resting values. MPA-treated animals had no measurable glucose recycling at rest or during exercise. Exercise decreased blood glucose concentration (35%) and increased blood lactate concentration (160%) in the MPA-treated animals. Exercising sham-injected animals had increased blood glucose (9.8%) but no change in blood lactate concentration. Moderate depletions in liver and skeletal muscle glycogen contents were observed after exercise

  12. Effects of turtle oil on insulin sensitivity and glucose metabolism in insulin resistant cell model

    International Nuclear Information System (INIS)

    Bai Jing; Tian Yaping; Guo Duo

    2007-01-01

    To evaluate the effects of turtle oil on insulin sensitivity and glucose metabolism in an insulin-resistant (IR) cell model which was established by the way of high concentration of insulin induction with HepG 2 cell in vitro culture. The IR cells were treated by turtle oil, the glucose consumption and 3 H-D-glucose incorporation rate in IR cells were detected by the way of glucose oxidase and 3 H-D-glucose incorporation assay respectively. The state of cell proliferation was tested by MTT method. The results showed that the incorporation rate of 3 H-D-glucose in IR cells was significantly lower than that in the control cells(P 3 H-D-glucose incorporation rate in either IR cells or control cells was increased with the increase of insulin concentration. Moreover, the 3 H-D-glucose incorporation rate of IR cells increased slower than that of control cells. The MTT assay showed that turtle oil can promote the proliferation of IR cell and control cell. The glucose uptake and glucose consumption in IR cell which treated with turtle oil was significantly increase than that in the control cells (P<0.05). Turtle oil can improve the insulin sensitivity and glucose metabolism in the IR cell model. (authors)

  13. Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration

    Energy Technology Data Exchange (ETDEWEB)

    Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.; Burgos, Patricia V.; Villanueva, Carolina I. [Department of Physiology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); Figueroa, Carlos D. [Department of Anatomy, Histology and Pathology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); González, Carlos B., E-mail: cbgonzal@uach.cl [Department of Physiology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555 (United States)

    2013-11-29

    Highlights: •AVP induces mTOR phosphorylation in A-10 cells cultured in high glucose concentration. •The mTOR phosphorylation is mediated by the PI3K/Akt pathway activation. •The AVP-induced mTOR phosphorylation inhibited autophagy and stimulated cell proliferation. -- Abstract: Mammalian target of rapamycin (mTOR) complex is a key regulator of autophagy, cell growth and proliferation. Here, we studied the effects of arginine vasopressin (AVP) on mTOR activation in vascular smooth muscle cells cultured in high glucose concentration. AVP induced the mTOR phosphorylation in A-10 cells grown in high glucose, in contrast to cells cultured in normal glucose; wherein, only basal phosphorylation was observed. The AVP-induced mTOR phosphorylation was inhibited by a PI3K inhibitor. Moreover, the AVP-induced mTOR activation inhibited autophagy and increased thymidine incorporation in cells grown in high glucose. This increase was abolished by rapamycin which inhibits the mTORC1 complex formation. Our results suggest that AVP stimulates mTOR phosphorylation by activating the PI3K/Akt signaling pathway and, subsequently, inhibits autophagy and raises cell proliferation in A-10 cells maintained in high glucose concentration.

  14. Sluggish glucose tolerance in tuberculosis patients | Bell | South ...

    African Journals Online (AJOL)

    Standard oral glucose tolerance tests (OGTTs) were performed in both groups in the morning after an overnight fast. Anticoagulant-treated blood was analysed for glucose and insulin using Peridochrome Glucose (Boehringer Mannheim, Mannheim, Germany) and radioimmunoassay (RIA) (Diagnostic Products Corporation, ...

  15. Inhibition of endothelial activation: a new way to treat cerebral malaria?

    Directory of Open Access Journals (Sweden)

    2005-09-01

    Full Text Available BACKGROUND: Malaria is still a major public health problem, partly because the pathogenesis of its major complication, cerebral malaria (CM, remains incompletely understood. However tumor necrosis factor (TNF is thought to play a key role in the development of this neurological syndrome, as well as lymphotoxin alpha (LT. METHODS AND FINDINGS: Using an in vitro model of CM based on human brain-derived endothelial cells (HBEC-5i, we demonstrate the anti-inflammatory effect of LMP-420, a 2-NH2-6-Cl-9-[(5-dihydroxyboryl-pentyl] purine that is a transcriptional inhibitor of TNF. When added before or concomitantly to TNF, LMP-420 inhibits endothelial cell (EC activation, i.e., the up-regulation of both ICAM-1 and VCAM-1 on HBEC-5i surfaces. Subsequently, LMP-420 abolishes the cytoadherence of ICAM-1-specific Plasmodium falciparum-parasitized red blood cells on these EC. Identical but weaker effects are observed when LMP-420 is added with LT. LMP-420 also causes a dramatic reduction of HBEC-5i vesiculation induced by TNF or LT stimulation, as assessed by microparticle release. CONCLUSION: These data provide evidence for a strong in vitro anti-inflammatory effect of LMP-420 and suggest that targeting host cell pathogenic mechanisms might provide a new therapeutic approach to improving the outcome of CM patients.

  16. Alterations in triglyceride rich lipoproteins are related to endothelial dysfunction in metabolic syndrome.

    Science.gov (United States)

    Lucero, Diego; López, Graciela I; Gorzalczany, Susana; Duarte, Mariano; González Ballerga, Esteban; Sordá, Juan; Schreier, Laura; Zago, Valeria

    2016-08-01

    Our aim was to analyze the effect of circulating triglyceride rich lipoprotein (TRL) on endothelial function in metabolic syndrome (MetS). We studied 40 patients with MetS (ATPIII), divided into those presenting normal endothelial function (n=19) and those with endothelial dysfunction (n=21) by means of the evaluation of pulse wave velocity, before and after brachial artery ischemia. In fasting serum we measured lipid and lipoprotein profile, insulin and glucose (HOMA-IR). Moreover, isolated TRL (d<1006g/l) were chemically characterized. In parallel, using randomly selected TRL from MetS patients with endothelial dysfunction (n=6) and MetS patients with normal endothelial function (n=6), the ability of TRL to inhibit ACh-induced vasorelaxation (10(-9)-10(-5)mM) on aortic rings previously pre-contracted by noradrenaline (10(-8)mM) was evaluated. Interestingly, TRL isolated from MetS patients presenting endothelial dysfunction showed triglyceride over-enrichment (59.1±4.8 vs. 54.1±4.7%; p=0.04), even after adjusting by potential confounders (p=0.05). In addition, while TRL resulting from both MetS groups significantly inhibited endothelium dependent vasorelaxation (p<0.001), TRL from MetS patients with endothelial dysfunction showed a strong tendency to a greater inhibition of vasorelaxation (p=0.06). Moreover, TRL-triglyceride (%) showed a strong tendency to correlate with the grade of vasorelaxation inhibition exerted by TRL (r=0.60; p=0.05). These results, taken together, would allow inferring for the first time that the predominance of triglyceride over-enriched TRL in circulation in MetS would induce endothelial dysfunction, contributing to the inherent cardiovascular risk of MetS. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  17. Overexpression of Hypoxia-Inducible Factor-1α Exacerbates Endothelial Barrier Dysfunction Induced by Hypoxia

    Directory of Open Access Journals (Sweden)

    Pei Wang

    2013-09-01

    Full Text Available Background/Aims: The mechanisms involved in endothelial barrier dysfunction induced by hypoxia are incompletely understood. There is debate about the role of hypoxia-inducible factor-1α (HIF-1α in endothelial barrier disruption. The aim of this study was to investigate the effect of genetic overexpression of HIF-1α on barrier function and the underlying mechanisms in hypoxic endothelial cells. Methods: The plasmid pcDNA3.1/V5-His-HIF-1α was stably transfected into human endothelial cells. The cells were exposed to normoxia or hypoxia. The mRNA and protein expressions of HIF-1α were detected by RT-PCR and Western blot respectively. The barrier function was assessed by measuring the transendothelial electrical resistance (TER. The Western blot analysis was used to determine the protein expression of glucose transporter-1 (GLUT-1, zonular occludens-1 (ZO-1, occludin, and myosin light chain kinase (MLCK in endothelial cells. The mRNA expression of proinflammatory cytokines was detected by qRT-PCR. Results: Genetic overexpression of HIF-1α significantly increased the mRNA and protein expression of HIF-1α in endothelial cells. The overexpression of HIF-1α enhanced the hypoxia-induced increase of HIF-1α and GLUT-1 protein expression. HIF-1α overexpression not only exacerbated hypoxia-induced endothelial barrier dysfunction but also augmented hypoxia-induced up-regulation of MLCK protein expression. HIF-1α overexpression also enhanced IL-1β, IL-6 and TNF-α mRNA expression. Conclusion: We provide evidence that genetic overexpression of HIF-1α aggravates the hypoxia-induced endothelial barrier dysfunction via enhancing the up-regulation of MLCK protein expression caused by hypoxia, suggesting a potential role for HIF-1α in the pathogenesis of endothelial barrier dysfunction in hypoxia.

  18. Dynamics of Receptor-Mediated Nanoparticle Internalization into Endothelial Cells

    Science.gov (United States)

    Gonzalez-Rodriguez, David; Barakat, Abdul I.

    2015-01-01

    Nanoparticles offer a promising medical tool for targeted drug delivery, for example to treat inflamed endothelial cells during the development of atherosclerosis. To inform the design of such therapeutic strategies, we develop a computational model of nanoparticle internalization into endothelial cells, where internalization is driven by receptor-ligand binding and limited by the deformation of the cell membrane and cytoplasm. We specifically consider the case of nanoparticles targeted against ICAM-1 receptors, of relevance for treating atherosclerosis. The model computes the kinetics of the internalization process, the dynamics of binding, and the distribution of stresses exerted between the nanoparticle and the cell membrane. The model predicts the existence of an optimal nanoparticle size for fastest internalization, consistent with experimental observations, as well as the role of bond characteristics, local cell mechanical properties, and external forces in the nanoparticle internalization process. PMID:25901833

  19. Berberine, a natural antidiabetes drug, attenuates glucose neurotoxicity and promotes Nrf2-related neurite outgrowth

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Ya-Yun [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Tseng, Yu-Ting [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Lo, Yi-Ching, E-mail: yichlo@kmu.edu.tw [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

    2013-11-01

    Reactive oxygen intermediates production and apoptotic damage induced by high glucose are major causes of neuronal damage in diabetic neuropathy. Berberine (BBR), a natural antidiabetes drug with PI3K-activating activity, holds promise for diabetes because of its dual antioxidant and anti-apoptotic activities. We have previously reported that BBR attenuated H{sub 2}O{sub 2} neurotoxicity via activating the PI3K/Akt/Nrf2-dependent pathway. In this study, we further explored the novel protective mechanism of BBR on high glucose-induced apoptotic death and neurite damage of SH-SY5Y cells. Results indicated BBR (0.1–10 nM) significantly attenuated reactive oxygen species (ROS) production, nucleus condensation, and apoptotic death in high glucose-treated cells. However, AG1024, an inhibitor of insulin growth factor-1 (IGF-1) receptor, significantly abolished BBR protection against high glucose-induced neuronal death. BBR also increased Bcl-2 expression and decreased cytochrome c release. High glucose down-regulated IGF-1 receptor and phosphorylation of Akt and GSK-3β, the effects of which were attenuated by BBR treatment. BBR also activated nuclear erythroid 2-related factor 2 (Nrf2), the key antioxidative transcription factor, which is accompanied with up-regulation of hemeoxygenase-1 (HO-1). Furthermore, BBR markedly enhanced nerve growth factor (NGF) expression and promoted neurite outgrowth in high glucose-treated cells. To further determine the role of the Nrf2 in BBR neuroprotection, RNA interference directed against Nrf2 was used. Results indicated Nrf2 siRNA abolished BBR-induced HO-1, NGF, neurite outgrowth and ROS decrease. In conclusion, BBR attenuated high glucose-induced neurotoxicity, and we are the first to reveal this novel mechanism of BBR as an Nrf2 activator against glucose neurotoxicity, providing another potential therapeutic use of BBR on the treatment of diabetic complications. - Highlights: • BBR attenuates high glucose-induced ROS

  20. Berberine, a natural antidiabetes drug, attenuates glucose neurotoxicity and promotes Nrf2-related neurite outgrowth

    International Nuclear Information System (INIS)

    Hsu, Ya-Yun; Tseng, Yu-Ting; Lo, Yi-Ching

    2013-01-01

    Reactive oxygen intermediates production and apoptotic damage induced by high glucose are major causes of neuronal damage in diabetic neuropathy. Berberine (BBR), a natural antidiabetes drug with PI3K-activating activity, holds promise for diabetes because of its dual antioxidant and anti-apoptotic activities. We have previously reported that BBR attenuated H 2 O 2 neurotoxicity via activating the PI3K/Akt/Nrf2-dependent pathway. In this study, we further explored the novel protective mechanism of BBR on high glucose-induced apoptotic death and neurite damage of SH-SY5Y cells. Results indicated BBR (0.1–10 nM) significantly attenuated reactive oxygen species (ROS) production, nucleus condensation, and apoptotic death in high glucose-treated cells. However, AG1024, an inhibitor of insulin growth factor-1 (IGF-1) receptor, significantly abolished BBR protection against high glucose-induced neuronal death. BBR also increased Bcl-2 expression and decreased cytochrome c release. High glucose down-regulated IGF-1 receptor and phosphorylation of Akt and GSK-3β, the effects of which were attenuated by BBR treatment. BBR also activated nuclear erythroid 2-related factor 2 (Nrf2), the key antioxidative transcription factor, which is accompanied with up-regulation of hemeoxygenase-1 (HO-1). Furthermore, BBR markedly enhanced nerve growth factor (NGF) expression and promoted neurite outgrowth in high glucose-treated cells. To further determine the role of the Nrf2 in BBR neuroprotection, RNA interference directed against Nrf2 was used. Results indicated Nrf2 siRNA abolished BBR-induced HO-1, NGF, neurite outgrowth and ROS decrease. In conclusion, BBR attenuated high glucose-induced neurotoxicity, and we are the first to reveal this novel mechanism of BBR as an Nrf2 activator against glucose neurotoxicity, providing another potential therapeutic use of BBR on the treatment of diabetic complications. - Highlights: • BBR attenuates high glucose-induced ROS production and

  1. Endothelial cells provide a notch-dependent pro-tumoral niche for enhancing breast cancer survival, stemness and pro-metastatic properties.

    Directory of Open Access Journals (Sweden)

    Pegah Ghiabi

    Full Text Available Treating metastasis has been challenging due to tumors complexity and heterogeneity. This complexity is partly related to the crosstalk between tumor and its microenvironment. Endothelial cells -the building blocks of tumor vasculature- have been shown to have additional roles in cancer progression than angiogenesis and supplying oxygen and nutrients. Here, we show an alternative role for endothelial cells in supporting breast cancer growth and spreading independent of their vascular functions. Using endothelial cells and breast cancer cell lines MDA-MB231 and MCF-7, we developed co-culture systems to study the influence of tumor endothelium on breast tumor development by both in vitro and in vivo approaches. Our results demonstrated that endothelial cells conferred survival advantage to tumor cells under complete starvation and enriched the CD44HighCD24Low/- stem cell population in tumor cells. Moreover, endothelial cells enhanced the pro-metastatic potential of breast cancer cells. The in vitro and in vivo results concordantly confirmed a role for endothelial Jagged1 to promote breast tumor through notch activation. Here, we propose a role for endothelial cells in enhancing breast cancer progression, stemness, and pro-metastatic traits through a perfusion-independent manner. Our findings may be beneficial in developing novel therapeutic approaches.

  2. Cyclosporine Induces Endothelial Cell Release of Complement-Activating Microparticles

    Science.gov (United States)

    Renner, Brandon; Klawitter, Jelena; Goldberg, Ryan; McCullough, James W.; Ferreira, Viviana P.; Cooper, James E.; Christians, Uwe

    2013-01-01

    Defective control of the alternative pathway of complement is an important risk factor for several renal diseases, including atypical hemolytic uremic syndrome. Infections, drugs, pregnancy, and hemodynamic insults can trigger episodes of atypical hemolytic uremic syndrome in susceptible patients. Although the mechanisms linking these clinical events with disease flares are unknown, recent work has revealed that each of these clinical conditions causes cells to release microparticles. We hypothesized that microparticles released from injured endothelial cells promote intrarenal complement activation. Calcineurin inhibitors cause vascular and renal injury and can trigger hemolytic uremic syndrome. Here, we show that endothelial cells exposed to cyclosporine in vitro and in vivo release microparticles that activate the alternative pathway of complement. Cyclosporine-induced microparticles caused injury to bystander endothelial cells and are associated with complement-mediated injury of the kidneys and vasculature in cyclosporine-treated mice. Cyclosporine-induced microparticles did not bind factor H, an alternative pathway regulatory protein present in plasma, explaining their complement-activating phenotype. Finally, we found that in renal transplant patients, the number of endothelial microparticles in plasma increases 2 weeks after starting tacrolimus, and treatment with tacrolimus associated with increased C3 deposition on endothelial microparticles in the plasma of some patients. These results suggest that injury-associated release of endothelial microparticles is an important mechanism by which systemic insults trigger intravascular complement activation and complement-dependent renal diseases. PMID:24092930

  3. Ozone modifies the metabolic and endocrine response to glucose: Reproduction of effects with the stress hormone corticosterone.

    Science.gov (United States)

    Thomson, Errol M; Pilon, Shinjini; Guénette, Josée; Williams, Andrew; Holloway, Alison C

    2018-03-01

    Air pollution is associated with increased incidence of metabolic disease (e.g. metabolic syndrome, obesity, diabetes); however, underlying mechanisms are poorly understood. Air pollutants increase the release of stress hormones (human cortisol, rodent corticosterone), which could contribute to metabolic dysregulation. We assessed acute effects of ozone, and stress axis involvement, on glucose tolerance and on the metabolic (triglyceride), endocrine/energy regulation (insulin, glucagon, GLP-1, leptin, ghrelin, corticosterone), and inflammatory/endothelial (TNF, IL-6, VEGF, PAI-1) response to exogenous glucose. Male Fischer-344 rats were exposed to clean air or 0.8 ppm ozone for 4 h in whole body chambers. Hypothalamic-pituitary-adrenal (HPA) axis involvement in ozone effects was tested through subcutaneous administration of the glucocorticoid synthesis inhibitor metyrapone (50 mg/kg body weight), corticosterone (10 mg/kg body weight), or vehicle (40% propylene glycol) prior to exposure. A glucose tolerance test (2 g/kg body weight glucose) was conducted immediately after exposure, with blood samples collected at 0, 30, 60, 90, and 120 min. Ozone exposure impaired glucose tolerance, an effect accompanied by increased plasma triglycerides but no impairment of insulin release. Ozone diminished glucagon, GLP-1, and ghrelin responses to glucose, but did not significantly impact inflammatory/endothelial analytes. Metyrapone reduced corticosterone but increased glucose and triglycerides, complicating evaluation of the impact of glucocorticoid inhibition. However, administration of corticosterone reproduced the profile of ozone effects, supporting a role for the HPA axis. The results show that ozone-dependent changes in glucose tolerance are accompanied by altered metabolic and endocrine responses to glucose challenge that are reproduced by exogenous stress hormone. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  4. Continuous Glucose Monitoring vs Conventional Therapy for Glycemic Control in Adults With Type 1 Diabetes Treated With Multiple Daily Insulin Injections: The GOLD Randomized Clinical Trial.

    Science.gov (United States)

    Lind, Marcus; Polonsky, William; Hirsch, Irl B; Heise, Tim; Bolinder, Jan; Dahlqvist, Sofia; Schwarz, Erik; Ólafsdóttir, Arndís Finna; Frid, Anders; Wedel, Hans; Ahlén, Elsa; Nyström, Thomas; Hellman, Jarl

    2017-01-24

    The majority of individuals with type 1 diabetes do not meet recommended glycemic targets. To evaluate the effects of continuous glucose monitoring in adults with type 1 diabetes treated with multiple daily insulin injections. Open-label crossover randomized clinical trial conducted in 15 diabetes outpatient clinics in Sweden between February 24, 2014, and June 1, 2016 that included 161 individuals with type 1 diabetes and hemoglobin A1c (HbA1c) of at least 7.5% (58 mmol/mol) treated with multiple daily insulin injections. Participants were randomized to receive treatment using a continuous glucose monitoring system or conventional treatment for 26 weeks, separated by a washout period of 17 weeks. Difference in HbA1c between weeks 26 and 69 for the 2 treatments. Adverse events including severe hypoglycemia were also studied. Among 161 randomized participants, mean age was 43.7 years, 45.3% were women, and mean HbA1c was 8.6% (70 mmol/mol). A total of 142 participants had follow-up data in both treatment periods. Mean HbA1c was 7.92% (63 mmol/mol) during continuous glucose monitoring use and 8.35% (68 mmol/mol) during conventional treatment (mean difference, -0.43% [95% CI, -0.57% to -0.29%] or -4.7 [-6.3 to -3.1 mmol/mol]; P < .001). Of 19 secondary end points comprising psychosocial and various glycemic measures, 6 met the hierarchical testing criteria of statistical significance, favoring continuous glucose monitoring compared with conventional treatment. Five patients in the conventional treatment group and 1 patient in the continuous glucose monitoring group had severe hypoglycemia. During washout when patients used conventional therapy, 7 patients had severe hypoglycemia. Among patients with inadequately controlled type 1 diabetes treated with multiple daily insulin injections, the use of continuous glucose monitoring compared with conventional treatment for 26 weeks resulted in lower HbA1c. Further research is needed to assess clinical outcomes and longer

  5. No difference between high-fructose and high-glucose diets on liver triacylglycerol or biochemistry in healthy overweight men.

    Science.gov (United States)

    Johnston, Richard D; Stephenson, Mary C; Crossland, Hannah; Cordon, Sally M; Palcidi, Elisa; Cox, Eleanor F; Taylor, Moira A; Aithal, Guruprasad P; Macdonald, Ian A

    2013-11-01

    Diets high in fructose have been proposed to contribute to nonalcoholic fatty liver disease. We compared the effects of high-fructose and matched glucose intake on hepatic triacylglycerol (TAG) concentration and other liver parameters. In a double-blind study, we randomly assigned 32 healthy but centrally overweight men to groups that received either a high-fructose or high-glucose diet (25% energy). These diets were provided during an initial isocaloric period of 2 weeks, followed by a 6-week washout period, and then again during a hypercaloric 2-week period. The primary outcome measure was hepatic level of TAG, with additional assessments of TAG levels in serum and soleus muscle, hepatic levels of adenosine triphosphate, and systemic and hepatic insulin resistance. During the isocaloric period of the study, both groups had stable body weights and concentrations of TAG in liver, serum, and soleus muscle. The high-fructose diet produced an increase of 22 ± 52 μmol/L in the serum level of uric acid, whereas the high-glucose diet led to a reduction of 23 ± 25 μmol/L (P fructose diet also produced an increase of 0.8 ± 0.9 in the homeostasis model assessment of insulin resistance, whereas the high-glucose diet produced an increase of only 0.1 ± 0.7 (P = .03). During the hypercaloric period, participants in the high-fructose and high-glucose groups had similar increases in weight (1.0 ± 1.4 vs 0.6 ± 1.0 kg; P = .29) and absolute concentration of TAG in liver (1.70% ± 2.6% vs 2.05% ± 2.9%; P = .73) and serum (0.36 ± 0.75 vs 0.33 ± 0.38 mmol/L; P = .91), and similar results in biochemical assays of liver function. Body weight changes were associated with changes in liver biochemistry and concentration of TAGs. In the isocaloric period, overweight men who were on a high-fructose or a high-glucose diet did not develop any significant changes in hepatic concentration of TAGs or serum levels of liver enzymes. However, in the hypercaloric period

  6. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... EXPO Volunteer Opportunities Sponsorship and Exhibit Opportunities Camp ... when ketones are present may make your blood glucose level go even higher. You'll need to work with your doctor ...

  7. An investigation on body weights, blood glucose levels and pituitary-gonadal axis hormones in diabetic and metformin-treated diabetic female rats

    Directory of Open Access Journals (Sweden)

    Pouya Pournaghi

    2012-06-01

    Full Text Available Diabetes is a metabolic disorder which affects whole body systems including reproductive system. Diabetes is also a contributing factor to infertility. Metformin is one of the most common drugs to control hyperglycemia. In this study, 36 adult Sprague-Dawley female rats (170-210 g were divided into 3 groups (control, diabetic and diabetic-treated by metformin. In second and third groups, diabetes was induced by streptozotocin injection (45 mg kg-1, IP and the third group was treated by metformin hydrochloride (100 mg kg-1 day-1, PO for 8 weeks. Body weights were compared and blood glucose, gonadotropins and sexual hormones were measured. In diabetic group the blood glucose level significantly (P < 0.05 increased in comparison with that of control and metformin-treated diabetic rats. The results also revealed that, in the untreated diabetic rats, the mean body weights and pituitary-gonadal axis hormones were significantly (P < 0.05 reduced in comparison with the control. Although there were significant (P < 0.05 reduction in mean body weights in metformin-treated diabetic rats, reduction in pituitary-gonadal axis hormones was not as sharp as in untreated diabetic rats and only level of progesterone was significantly (P < 0.05 reduced in comparison with the control. The results of this investigation revealed that there was a clear relationship between experimental diabetes with body weight and pituitary-gonadal axis hormones, and treatment with metformin relatively restored diabetic complications.

  8. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Care Blood Glucose Testing Medication Doctors, Nurses & More Oral ... someone new is diagnosed. Diabetes causes more deaths a year than breast cancer and AIDS combined. Your gift today will help ...

  9. Production of water-soluble yellow pigments via high glucose stress fermentation of Monascus ruber CGMCC 10910.

    Science.gov (United States)

    Wang, Meihua; Huang, Tao; Chen, Gong; Wu, Zhenqiang

    2017-04-01

    Monascus pigments are secondary metabolites of Monascus species and are mainly composed of yellow pigments, orange pigments and red pigments. In this study, a larger proportion of Monascus yellow pigments could be obtained through the selection of the carbon source. Hydrophilic yellow pigments can be largely produced extracellularly by Monascus ruber CGMCC 10910 under conditions of high glucose fermentation with low oxidoreduction potential (ORP). However, keeping high glucose levels later in the culture causes translation or a reduction of yellow pigment. We presume that the mechanism behind this phenomenon may be attributed to the redox level of the culture broth and the high glucose stress reaction of M. ruber CGMCC 10910 during high glucose fermentation. These yellow pigments were produced via high glucose bio-fermentation without citrinin. Therefore, these pigments can act as natural pigments for applications as food additives.

  10. Biological response of rats fed with tofu treated with high hydrostatic pressure.

    Science.gov (United States)

    Préstamo, G; Arroyo, G

    2000-10-01

    Emerging technologies for food preservation have arisen in recent years, such as high-pressure (HP) hydrostatic treatment, and the biological response for this kind of food preservation is not well-known. Forty female rats (six weeks old) were used in the experiment to evaluate the biological effects of HP treatment of tofu. The animals were divided into groups that were fed with tofu (untreated), tofu treated with HP, and conventional food (as control) for 28 days. The glucose level, mineral content (calcium, potassium, zinc, and magnesium), shinbone maximum shear force, weight of the body, and weight of organs (heart, liver, spleen, and kidneys) were analyzed. The biological response for the rats was that significant differences were found in the calcium amount determined on the serum of the rats fed with untreated tofu and those fed with tofu treated with HP, and the calcium amount was lower on the rats fed with tofu treated with HP. Also, there were significant differences in the weight of the liver, and it was lower in the rats fed with tofu treated with HP. It was quite remarkable how the weight of the body and organs were smaller in the rats fed with tofu in comparison to the weight of the control rats. In the other components assayed no significant differences were found. HP produces a potential effect on tofu as it is observed in the rats response to the tofu treated with HP.

  11. Role of Hepatic Lipase and Endothelial Lipase in High-Density Lipoprotein-Mediated Reverse Cholesterol Transport

    NARCIS (Netherlands)

    Annema, Wijtske; Tietge, Uwe J. F.

    Reverse cholesterol transport (RCT) constitutes a key part of the atheroprotective properties of high-density lipoproteins (HDL). Hepatic lipase (HL) and endothelial lipase (EL) are negative regulators of plasma HDL cholesterol levels. Although overexpression of EL decreases overall

  12. Negative Effects of High Glucose Exposure in Human Gonadotropin-Releasing Hormone Neurons

    OpenAIRE

    Morelli, Annamaria; Comeglio, Paolo; Sarchielli, Erica; Cellai, Ilaria; Vignozzi, Linda; Vannelli, Gabriella B.; Maggi, Mario

    2013-01-01

    Metabolic disorders are often associated with male hypogonadotropic hypogonadism, suggesting that hypothalamic defects involving GnRH neurons may impair the reproductive function. Among metabolic factors hyperglycemia has been implicated in the control of the reproductive axis at central level, both in humans and in animal models. To date, little is known about the direct effects of pathological high glucose concentrations on human GnRH neurons. In this study, we investigated the high glucose...

  13. Unfractionated Heparin Alleviates Human Lung Endothelial Barrier Dysfunction Induced by High Mobility Group Box 1 Through Regulation of P38–GSK3β–Snail Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Zhenggang Luan

    2018-04-01

    Full Text Available Background/Aims: The high mobility group box 1 (HMGB1 has been regarded as an important inflammatory mediator. Previous studies showed the involvement of HMGB1 protein in the dysfunction of endothelial barrier function during acute lung injury. However, the molecular mechanism remains unclear. Methods: In this study, we used recombinant human HMGB1 (rhHMGB1 and HMGB1 plasmid to treat human pulmonary microvascular endothelial cell (HPMECs. We examined endothelial permeability by measuring TEER value and HRP flux. Western blot and real-time PCR were used to examined change of endothelial-to-mesenchymal transition (EndoMT markers and related pathways. Immunofluorescence was used to examine localization and expression of ZO-1 and VE-cadherin. SB203580.was used to block p38 pathway. Unfractionated heparin (UFH and RAGE siRNA were also used to antagonize the effect of HMGB1. Results: We showed that HMGB1 induced EndoMT with downregulation of ZO-1 and VE-cadherin at both mRNA and protein levels in HPMECs. We also demonstrated that HMGB1 upregulated endothelial permeability by measuring TEER value and HRP flux. Moreover, HMGB1 activated p38/GSK3β/Snail signaling pathway and treatment with p38 inhibitor SB203580 abolished its biological effects. In addition, we found that UFH was able to reverse the effect of HMGB1 on EndoMT and endothelial permeability through inhibition of p38 signaling in a dose-dependent manner. We discovered that RAGE, a membrane receptor of HMGB1, transduced p38/Snail pathway to EndoMT. RAGE siRNA inhibited the effect of HMGB1 induced EndoMT in HPMECs. Conclusion: The present study demonstrated that HMGB1 induced EndoMT through RAGE receptor and p38/GSK3β/Snail pathway. While UFH antagonized HMGB1 and maintained the integrity of the endothelial barrier through p38 inhibition.

  14. Atypical Presentation of Iridocorneal Endothelial Syndrome With Band Keratopathy but No Corneal Edema Managed With Descemet Membrane Endothelial Keratoplasty.

    Science.gov (United States)

    Zygoura, Vasiliki; Lavy, Itay; Verdijk, Robert M; Santander-García, Diana; Baydoun, Lamis; Dapena, Isabel; Melles, Gerrit R J

    2018-04-17

    To report an unusual presentation of iridocorneal endothelial (ICE) syndrome associated with band keratopathy and its management with ethylenediamine-tetraacetic acid (EDTA) chelation and Descemet membrane endothelial keratoplasty (DMEK). A 57-year-old female patient presented with unilateral progressive painless visual impairment, corneal band keratopathy, and morphological corneal endothelial changes without corneal edema or any previous ophthalmic, medical, or family history. Routine specular and confocal microscopy imaging, as well as biomicroscopy, best-corrected visual acuity, and pachymetry measurements were performed before and after the surgical procedures. Histopathologic and immunohistochemical evaluations of the surgically excised diseased DM-endothelium were performed. Superficial epithelial keratectomy with EDTA chelation was performed. After an initial period of a few months of corneal clearance, the patient presented with recurrence of visually significant band keratopathy. After 1 year, she underwent retreatment with superficial epithelial keratectomy and EDTA chelation, followed by DMEK. Histopathologic and immunohistochemical analysis showed ICE syndrome. Two years after DMEK surgery, the cornea was still clear and band keratopathy had not recurred. To the best of our knowledge, this is the first case in the literature that reports the association of ICE syndrome with band keratopathy. As band keratopathy recurred shortly after EDTA chelation, endothelial keratoplasty (DMEK) may be indicated to successfully treat such cases.

  15. Twenty-four-hour variations in blood glucose level in Japanese type 2 diabetes patients based on continuous glucose monitoring.

    Science.gov (United States)

    Hajime, Maiko; Okada, Yosuke; Mori, Hiroko; Otsuka, Takashi; Kawaguchi, Mayuko; Miyazaki, Megumi; Kuno, Fumi; Sugai, Kei; Sonoda, Satomi; Tanaka, Kenichi; Kurozumi, Akira; Narisawa, Manabu; Torimoto, Keiichi; Arao, Tadashi; Tanaka, Yoshiya

    2018-01-01

    High fluctuations in blood glucose are associated with various complications. The correlation between glycated hemoglobin (HbA1c) level and fluctuations in blood glucose level has not been studied in Japanese patients with type 2 diabetes. In the present study, blood glucose profile stratified by HbA1c level was evaluated by continuous glucose monitoring (CGM) in Japanese type 2 diabetes patients. Our retrospective study included 294 patients with type 2 diabetes who were divided by HbA1c level into five groups (≥6.0 to level and CGM data was analyzed. The primary end-point was the difference in blood glucose fluctuations among the HbA1c groups. The mean blood glucose level increased significantly with increasing HbA1c (P trend  levels of maximum blood glucose, minimum blood glucose, each preprandial blood glucose, each postprandial maximum blood glucose, range of increase in postprandial glucose from pre-meal to after breakfast, the area under the blood concentration-time curve >180 mg/dL and percentage of the area under the blood concentration-time curve >180 mg/dL were higher with higher HbA1c. Mean glucose level and pre-breakfast blood glucose level were significant and independent determinants of HbA1c. In Japanese patients treated for type 2 diabetes, the mean amplitude of glycemic excursions did not correlate with HbA1c, making it difficult to assess blood glucose fluctuations using HbA1c. Parameters other than HbA1c are required to evaluate fluctuations in blood glucose level in patients receiving treatment for type 2 diabetes. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  16. [High frequency electrocoagulation for treating noninvoluting congenital hemangioma].

    Science.gov (United States)

    Zhongqiang, Wang; Yafei, Wang; Jiashuang, Zhou; Quan, Zhou; Lijuan, Yang; Li, Wang

    2015-11-01

    To investigate the clinical efficiency of electrocoagulation for the treatment of noninvoluting congenital hemangioma. Sixteen infants with noninvoluting congenital hemangioma who were admitted to our hospital from January 2011 to June 2013 were included in this study. Color Doppler ultrasound was used to determine the hemangioma location, as well as its size and depth. High frequency electrocoagulation was adopted for the treatment. The output power was set at 10-20 W. The probes were inserted around the tumor or at the surface of the tumor. After switching on for 1-2 seconds, the direction and position of the probe was modulated until covering the whole tumor. After the treatment, the absorption of tumor was about 3-6 months. The efficiency was evaluated during the follow-up. Tumor atrophy was obvious after treatment in all patients. The temperature around the tumor mass was decreased, and the aberrant blood signals were decreased under the ultrasonic examination. Complete or partial atrophy were observed. The efficiency was graded as level I, II, III, IV in 0, 2, 9 and 5 patients, respectively. One patient showed local infection due to improper nursing, which was completely relieved after corresponding treatment. No severe adverse events were observed. High-frequency electrocoagulation is effective for treating noninvoluting congenital hemangioma through coagulating the aberrant blood vessels in the tumor, interrupting the vascular endothelial cell, blocking the aberrant blood flow, as well as leading to atrophy and absorption of tumor mass. Besides, no obvious scar is observed after the surgery.

  17. Tin-containing zeolites are highly active catalysts for the isomerization of glucose in water

    OpenAIRE

    Moliner, Manuel; Román-Leshkov, Yuriy; Davis, Mark E.

    2010-01-01

    The isomerization of glucose into fructose is a large-scale reaction for the production of high-fructose corn syrup (HFCS; reaction performed by enzyme catalysts) and recently is being considered as an intermediate step in the possible route of biomass to fuels and chemicals. Here, it is shown that a large-pore zeolite that contains tin (Sn-Beta) is able to isomerize glucose to fructose in aqueous media with high activity and selectivity. Specifically, a 10% (wt/wt) glucose solution containin...

  18. A biphasic endothelial stress-survival mechanism regulates the cellular response to vascular endothelial growth factor A

    International Nuclear Information System (INIS)

    Latham, Antony M.; Odell, Adam F.; Mughal, Nadeem A.; Issitt, Theo; Ulyatt, Clare; Walker, John H.; Homer-Vanniasinkam, Shervanthi; Ponnambalam, Sreenivasan

    2012-01-01

    Vascular endothelial growth factor A (VEGF-A) is an essential cytokine that regulates endothelial function and angiogenesis. VEGF-A binding to endothelial receptor tyrosine kinases such as VEGFR1 and VEGFR2 triggers cellular responses including survival, proliferation and new blood vessel sprouting. Increased levels of a soluble VEGFR1 splice variant (sFlt-1) correlate with endothelial dysfunction in pathologies such as pre-eclampsia; however the cellular mechanism(s) underlying the regulation and function of sFlt-1 are unclear. Here, we demonstrate the existence of a biphasic stress response in endothelial cells, using serum deprivation as a model of endothelial dysfunction. The early phase is characterized by a high VEGFR2:sFlt-1 ratio, which is reversed in the late phase. A functional consequence is a short-term increase in VEGF-A-stimulated intracellular signaling. In the late phase, sFlt-1 is secreted and deposited at the extracellular matrix. We hypothesized that under stress, increased endothelial sFlt-1 levels reduce VEGF-A bioavailability: VEGF-A treatment induces sFlt-1 expression at the cell surface and VEGF-A silencing inhibits sFlt-1 anchorage to the extracellular matrix. Treatment with recombinant sFlt-1 inhibits VEGF-A-stimulated in vitro angiogenesis and sFlt-1 silencing enhances this process. In this response, increased VEGFR2 levels are regulated by the phosphatidylinositol-3-kinase and PKB/Akt signaling pathways and increased sFlt-1 levels by the ERK1/2 signaling pathway. We conclude that during serum withdrawal, cellular sensing of environmental stress modulates sFlt-1 and VEGFR2 levels, regulating VEGF-A bioavailability and ensuring cell survival takes precedence over cell proliferation and migration. These findings may underpin an important mechanism contributing to endothelial dysfunction in pathological states. -- Highlights: ► Endothelial cells mount a stress response under conditions of low serum. ► Endothelial VEGFR levels are

  19. Andrographolide suppresses high glucose-induced fibronectin expression in mesangial cells via inhibiting the AP-1 pathway.

    Science.gov (United States)

    Lan, Tian; Wu, Teng; Gou, Hongju; Zhang, Qianqian; Li, Jiangchao; Qi, Cuiling; He, Xiaodong; Wu, Pingxiang; Wang, Lijing

    2013-11-01

    Mesangial cells (MCs) proliferation and accumulation of glomerular matrix proteins such as fibronectin (FN) are the early features of diabetic nephropathy, with MCs known to upregulate matrix protein synthesis in response to high glucose. Recently, it has been found that andrographolide has renoprotective effects on diabetic nephropathy. However, the molecular mechanism underlying these effects remains unclear. Cell viability and proliferation was evaluated by MTT. FN expression was examined by immunofluorescence and immunoblotting. Activator protein-1 (AP-1) activation was assessed by immunoblotting, luciferase reporter and electrophoretic mobility shift assays. Andrographolide significantly decreased high glucose-induced cell proliferation and FN expression in MCs. Exposure of MCs to high glucose markedly stimulated the expression of phosphorylated c-jun, whereas the stimulation was inhibited by andrographolide. Plasmid pAP-1-Luc luciferase reporter assay showed that andrographolide blocked high glucose-induced AP-1 transcriptional activity. EMSA assay demonstrated that increased AP-1 binding to an AP-1 binding site at -1,029 in the FN gene promoter upon high glucose stimulation, and the binding were disrupted by andrographolide treatment. These data indicate that andrographolide suppresses high glucose-induced FN expression by inhibiting AP-1-mediated pathway. © 2013 Wiley Periodicals, Inc.

  20. Increased Insulin following an Oral Glucose Load, Genetic Variation near the Melatonin Receptor MTNR1B, but No Biochemical Evidence of Endothelial Dysfunction in Young Asian Men and Women.

    Directory of Open Access Journals (Sweden)

    Maria A Matuszek

    Full Text Available To identify biochemical and genetic variation relating to increased risk of developing type 2 diabetes mellitus and cardiovascular disease in young, lean male and female adults of different ethnicities.Fasting blood and urine and non-fasting blood following oral glucose intake were analysed in 90 Caucasians, South Asians and South East/East Asians.There were no differences in age, birthweight, blood pressure, body mass index, percent body fat, total energy, percentage of macronutrient intake, microalbumin, leptin, cortisol, adrenocorticotropic hormone, nitric oxide metabolites, C-reactive protein, homocysteine, tumor necrosis factor-α, interleukin-6, von Willebrand factor, vascular cell adhesion molecule-1, plasminogen activator inhibitor-1, and tissue plasminogen activator. Fasting total cholesterol (P = .000, triglycerides (P = .050, low density lipoprotein (P = .009 and non-fasting blood glucose (15 min (P = .024 were elevated in South Asians compared with Caucasians, but there was no significant difference in glucose area under curve (AUC. Non-fasting insulin in South Asians (15-120 min, in South East/East Asians (60-120 min, and insulin AUC in South Asians and South East/East Asians, were elevated compared with Caucasians (P≤0.006. The molar ratio of C-peptide AUC/Insulin AUC (P = .045 and adiponectin (P = .037 were lower in South Asians compared with Caucasians. A significant difference in allele frequency distributions in Caucasians and South Asians was found for rs2166706 (P = 0.022 and rs10830963 (P = 0.009, which are both near the melatonin receptor MTNR1B.Elevated non-fasting insulin exists in young South Asians of normal fasting glucose and insulin. Hepatic clearance of insulin may be reduced in South Asians. No current biochemical evidence exists of endothelial dysfunction at this stage of development. MTNR1B signalling may be a useful therapeutic target in Asian populations in the prevention of type 2 diabetes mellitus.

  1. Increased Insulin following an Oral Glucose Load, Genetic Variation near the Melatonin Receptor MTNR1B, but No Biochemical Evidence of Endothelial Dysfunction in Young Asian Men and Women.

    Science.gov (United States)

    Matuszek, Maria A; Anton, Angelyn; Thillainathan, Sobana; Armstrong, Nicola J

    2015-01-01

    To identify biochemical and genetic variation relating to increased risk of developing type 2 diabetes mellitus and cardiovascular disease in young, lean male and female adults of different ethnicities. Fasting blood and urine and non-fasting blood following oral glucose intake were analysed in 90 Caucasians, South Asians and South East/East Asians. There were no differences in age, birthweight, blood pressure, body mass index, percent body fat, total energy, percentage of macronutrient intake, microalbumin, leptin, cortisol, adrenocorticotropic hormone, nitric oxide metabolites, C-reactive protein, homocysteine, tumor necrosis factor-α, interleukin-6, von Willebrand factor, vascular cell adhesion molecule-1, plasminogen activator inhibitor-1, and tissue plasminogen activator. Fasting total cholesterol (P = .000), triglycerides (P = .050), low density lipoprotein (P = .009) and non-fasting blood glucose (15 min) (P = .024) were elevated in South Asians compared with Caucasians, but there was no significant difference in glucose area under curve (AUC). Non-fasting insulin in South Asians (15-120 min), in South East/East Asians (60-120 min), and insulin AUC in South Asians and South East/East Asians, were elevated compared with Caucasians (P≤0.006). The molar ratio of C-peptide AUC/Insulin AUC (P = .045) and adiponectin (P = .037) were lower in South Asians compared with Caucasians. A significant difference in allele frequency distributions in Caucasians and South Asians was found for rs2166706 (P = 0.022) and rs10830963 (P = 0.009), which are both near the melatonin receptor MTNR1B. Elevated non-fasting insulin exists in young South Asians of normal fasting glucose and insulin. Hepatic clearance of insulin may be reduced in South Asians. No current biochemical evidence exists of endothelial dysfunction at this stage of development. MTNR1B signalling may be a useful therapeutic target in Asian populations in the prevention of type 2 diabetes mellitus.

  2. E2f1 mediates high glucose-induced neuronal death in cultured mouse retinal explants.

    Science.gov (United States)

    Wang, Yujiao; Zhou, Yi; Xiao, Lirong; Zheng, Shijie; Yan, Naihong; Chen, Danian

    2017-10-02

    Diabetic retinopathy (DR) is the most common complication of diabetes and remains one of the major causes of blindness in the world; infants born to diabetic mothers have higher risk of developing retinopathy of prematurity (ROP). While hyperglycemia is a major risk factor, the molecular and cellular mechanisms underlying DR and diabetic ROP are poorly understood. To explore the consequences of retinal cells under high glucose, we cultured wild type or E2f1 -/- mouse retinal explants from postnatal day 8 with normal glucose, high osmotic or high glucose media. Explants were also incubated with cobalt chloride (CoCl 2 ) to mimic the hypoxic condition. We showed that, at 7 days post exposure to high glucose, retinal explants displayed elevated cell death, ectopic cell division and intact retinal vascular plexus. Cell death mainly occurred in excitatory neurons, such as ganglion and bipolar cells, which were also ectopically dividing. Many Müller glial cells reentered the cell cycle; some had irregular morphology or migrated to other layers. High glucose inhibited the hyperoxia-induced blood vessel regression of retinal explants. Moreover, inactivation of E2f1 rescued high glucose-induced ectopic division and cell death of retinal neurons, but not ectopic cell division of Müller glial cells and vascular phenotypes. This suggests that high glucose has direct but distinct effects on retinal neurons, glial cells and blood vessels, and that E2f1 mediates its effects on retinal neurons. These findings shed new light onto mechanisms of DR and the fetal retinal abnormalities associated with maternal diabetes, and suggest possible new therapeutic strategies.

  3. A flexible and highly sensitive nonenzymatic glucose sensor based on DVD-laser scribed graphene substrate.

    Science.gov (United States)

    Lin, Songyue; Feng, Wendou; Miao, Xiaofei; Zhang, Xiangxin; Chen, Sujing; Chen, Yuanqiang; Wang, Wei; Zhang, Yining

    2018-07-01

    Flexible and implantable glucose biosensors are emerging technologies for continuous monitoring of blood-glucose of diabetes. Developing a flexible conductive substrates with high active surface area is critical for advancing the technology. Here, we successfully fabricate a flexible and highly sensitive nonenzymatic glucose by using DVD-laser scribed graphene (LSG) as a flexible conductively substrate. Copper nanoparticles (Cu-NPs) are electrodeposited as the catalyst. The LSG/Cu-NPs sensor demonstrates excellent catalytic activity toward glucose oxidation and exhibits a linear glucose detection range from 1 μM to 4.54 mM with high sensitivity (1.518 mA mM -1 cm -2 ) and low limit of detection (0.35 μM). Moreover, the LSG/Cu-NPs sensor shows excellent reproducibility and long-term stability. It is also highly selective toward glucose oxidation under the presence of various interfering species. Excellent flexing stability is also demonstrated by the LSG/Cu-NPs sensor, which is capable of maintaining 83.9% of its initial current after being bent against a 4-mm diameter rod for 180 times. The LSG/Cu-NPs sensor shows great potential for practical application as a nonenzymatic glucose biosensor. Meanwhile, the LSG conductive substrate provides a platform for the developing next-generation flexible and potentially implantable bioelectronics and biosensors. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Highly sensitive glucose sensor based on monodisperse palladium nickel/activated carbon nanocomposites.

    Science.gov (United States)

    Koskun, Yağmur; Şavk, Aysun; Şen, Betül; Şen, Fatih

    2018-06-20

    Glucose enzyme biosensors have been used for a variety of applications such as medical diagnosis, bioprocess engineering, beverage industry and environmental scanning etc. and there is still a growing interest in glucose sensors. For this purpose, addressed herein, as a novel glucose sensor, highly sensitive activated carbon (AC) decorated monodisperse nickel and palladium alloy nanocomposites modified glassy carbon electrode (Ni-Pd@AC/GCE NCs) have been synthesized by in-situ reduction technique. Raman Spectroscopy (RS), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), cyclic voltammetry (CV) and chronoamperometry (CA) were used for the characterization of the prepared non-enzymatic glucose sensor. The characteristic sensor properties of the Ni-Pd@AC/GCE electrode were compared with Ni-Pd NCs/GCE, Ni@AC/GCE and Pd@AC/GCE and the results demonstrate that the AC is very effective in the enhancement of the electrocatalytic properties of sensor. In addition, the Ni-Pd@AC/GCE nanocomposites showed a very low detection limit of 0.014 μM, a wide linear range of 0.01 mM-1 mM and a very high sensitivity of 90 mA mM -1  cm -2 . Furthermore, the recommended sensor offer the various advantageous such as facile preparation, fast response time, high selectivity and sensitivity. Lastly, monodisperse Ni-Pd@AC/GCE was utilized to detect glucose in real sample species. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Strategies for glucose control in a study population with diabetes, renal disease and anemia (Treat study).

    Science.gov (United States)

    Weinrauch, Larry A; D'Elia, John A; Finn, Peter; Lewis, Eldrin F; Desai, Akshay S; Claggett, Brian L; Cooper, Mark E; McGill, Janet B

    2016-03-01

    Glucose lowering medication use among patients with type 2 diabetes and advanced renal disease (eGFRrenal disease advances, most of the oral anti-diabetic agents requiring renal clearance must be reduced or discontinued. The potential for prolonged hypoglycemia, fluid/volume overload and congestive heart failure may complicate medication choices. In order to evaluate patterns of glycemia management we describe glucose lowering medication use among patients with advanced renal disease and type 2 diabetes in a large multinational outcome trial designed to focus on patients with eGFRrenal function when compared with standard populations with normal kidney function. The use of multiple oral agents, or oral agents plus insulin was quite common. While gender did not appear to play a role in medication choices, there were significant regional variations. For example, oral agents were used more in North America compared with other regions (Latin America, Australia/Western Europe, Russia/Eastern Europe). Patients enrolled at more advanced ages were less likely to be on a regimen of rapid-acting insulin alone consistent with recommendations that suggest a preference for longer-acting preparations in the geriatric population (1). Higher degrees of obesity were associated more complex treatment regimens. Despite this population being at high risk for cardiovascular events, the use of beta blockers (50%), statins (64%) and aspirin (48%) were relatively low, especially in the group that did not require medications to achieve adequate glycemic control. Current attempts to compare strategies for diabetes therapy must control for baseline demographic group differences influencing treatment choice. Future recommendations for glycemic control in patients with Grade 3 or higher chronic kidney disease require additional studies, with matched populations. We suggest that evaluation of studies similar to TREAT will assist in determining the optimal therapeutic regimens for populations

  6. Unhealthy Phenotype as Indicated by Salivary Biomarkers: Glucose, Insulin, VEGF-A, and IL-12p70 in Obese Kuwaiti Adolescents

    Directory of Open Access Journals (Sweden)

    Mor-Li Hartman

    2016-01-01

    Full Text Available Objective. Here, we investigated the relationships between obesity and the salivary concentrations of insulin, glucose, and 20 metabolic biomarkers in Kuwaiti adolescents. Previously, we have shown that certain salivary metabolic markers can act as surrogates for blood concentrations. Methods. Salivary samples of whole saliva were collected from 8,317 adolescents. Salivary glucose concentration was measured by a high-sensitivity glucose oxidase method implemented on a robotic chemical analyzer. The concentration of salivary insulin and 20 other metabolic biomarkers was assayed in 744 randomly selected saliva samples by multiplexed bead-based immunoassay. Results. Obesity was seen in 26.5% of the adolescents. Salivary insulin predicting hyperinsulinemia occurred in 4.3% of normal-weight adolescents, 8.3% of overweight adolescents, and 25.7% of obese adolescents (p<0.0001. Salivary glucose predicting hyperglycemia was found in only 3% of obese children and was not predictive (p=0.89. Elevated salivary glucose and insulin occurring together was associated with elevated vascular endothelial growth factor and reduced salivary interleukin-12. Conclusion. Considering the surrogate nature of salivary insulin and glucose, this study suggests that elevated insulin may be a dominant sign of metabolic disease in adolescent populations. It also appears that a proangiogenic environment may accompany elevated glucose in obese adolescents.

  7. Targeted Modification of Mitochondrial ROS Production Converts High Glucose-Induced Cytotoxicity to Cytoprotection: Effects on Anesthetic Preconditioning.

    Science.gov (United States)

    Sedlic, Filip; Muravyeva, Maria Y; Sepac, Ana; Sedlic, Marija; Williams, Anna Marie; Yang, Meiying; Bai, Xiaowen; Bosnjak, Zeljko J

    2017-01-01

    Contradictory reports on the effects of diabetes and hyperglycemia on myocardial infarction range from cytotoxicity to cytoprotection. The study was designed to investigate acute effects of high glucose-driven changes in mitochondrial metabolism and osmolarity on adaptive mechanisms and resistance to oxidative stress of isolated rat cardiomyocytes. We examined the effects of high glucose on several parameters of mitochondrial bioenergetics, including changes in oxygen consumption, mitochondrial membrane potential, and NAD(P)H fluorometry. Effects of high glucose on the endogenous cytoprotective mechanisms elicited by anesthetic preconditioning (APC) and the mediators of cell injury were also tested. These experiments included real-time measurements of reactive oxygen species (ROS) production and mitochondrial permeability transition pore (mPTP) opening in single cells by laser scanning fluorescence confocal microscopy, and cell survival assay. High glucose rapidly enhanced mitochondrial energy metabolism, observed by increase in NAD(P)H fluorescence intensity, oxygen consumption, and mitochondrial membrane potential. This substantially elevated production of ROS, accelerated opening of the mPTP, and decreased survival of cells exposed to oxidative stress. Abrogation of high glucose-induced mitochondrial hyperpolarization with 2,4 dinitrophenol (DNP) significantly, but not completely, attenuated ROS production to a level similar to hyperosmotic mannitol control. DNP treatment reversed high glucose-induced cytotoxicity to cytoprotection. Hyperosmotic mannitol treatment also induced cytoprotection. High glucose abrogated APC-induced mitochondrial depolarization, delay in mPTP opening and cytoprotection. In conclusion, high glucose-induced mitochondrial hyperpolarization abolishes APC and augments cell injury. Attenuation of high glucose-induced ROS production by eliminating mitochondrial hyperpolarization protects cardiomyocytes. J. Cell. Physiol. 232: 216-224, 2017

  8. Hyperglycemia (High Blood Glucose)

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  16. Effects on the glucose metabolism in type II diabetes model mice treated with dose-rates irradiation

    International Nuclear Information System (INIS)

    Nomura, Takaharu; Sakai, Kazuo

    2004-01-01

    The effects of low-dose rate gamma-irradiation on the type II diabetes mellitus were investigated in C57BL/KsJ-ab/db (db mouse). This mouse develops the type II diabetes within 8 weeks of the birth due to a dysfunction of the insulin receptors. As a result the db mouse shows obese and exhibits hyperinsulinism. Ten-week old female mice (12 mice in each group) were irradiated with gamma-rays at 0.35 mGy/hr, 0.65 mGy/hr or 1.2 mGy/hr in the low-dose rate irradiation facility in the Low Dose Radiation Research Center. The level of plasma glucose and insulin was measured. After 2 weeks irradiation, the glucose level slightly increased, however the difference between the irradiated mice and non-irradiated groups was not significant. The plasma insulin concentration decreased in the non-irradiated group to half of the initial level. In the irradiated group, it also decreased but in the group of 0.65 mGy/hr and 0.35 mGy/hr, it was significantly differed from that in the non-irradiated group. In the glucose tolerance test, plasma glucose level increased shortly after 0.1 mg/head glucose injection by mouth and reached to a peak at 90-120 min after the injection. The glucose level of the non-irradiated mice was slightly higher than that of irradiated mice. The plasma insulin level of non-irradiated group was enhanced after the injection and maintained the level during the test. However the levels of irradiated mice were decreased at 30-60 min after the injection. Both the level of non-irradiated an irradiated was almost same but the non-irradiated one was a little high. In all of mice, the plasma insulin level was highly elevated right after the 0.05 units/head insulin injection by i.p. and the levels were also gradually decreased. The level of the non-irradiated group was slowly decreased and was higher than the irradiated mice. The plasma glucose levels of all mice did not change after the test; however, the levels of irradiated mice were slightly lower than that of non

  17. Hyperglycemia (High Blood Glucose)

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  19. Hyperglycemia (High Blood Glucose)

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  20. Impact of high-fat diet and voluntary running on body weight and endothelial function in LDL receptor knockout mice.

    Science.gov (United States)

    Langbein, Heike; Hofmann, Anja; Brunssen, Coy; Goettsch, Winfried; Morawietz, Henning

    2015-05-01

    Obesity and physical inactivity are important cardiovascular risk factors. Regular physical exercise has been shown to mediate beneficial effects in the prevention of cardiovascular diseases. However, the impact of physical exercise on endothelial function in proatherosclerotic low-density lipoprotein receptor deficient (LDLR(-/-)) mice has not been studied so far. Six-week-old male LDLR(-/-) mice were fed a standard diet or a high-fat diet (39 kcal% fat diet) for 20 weeks. The impact of high-fat diet and voluntary running on body weight and amount of white adipose tissue was monitored. Basal tone and endothelial function was investigated in aortic rings using a Mulvany myograph. LDLR(-/-) mice on high-fat diet had increased cumulative food energy intake, but also higher physical activity compared to mice on control diet. Body weight and amount of visceral and retroperitoneal white adipose tissue of LDLR(-/-) mice were significantly increased by high-fat diet and partially reduced by voluntary running. Endothelial function in aortae of LDLR(-/-) mice was impaired after 20 weeks on standard and high-fat diet and could not be improved by voluntary running. Basal tone showed a trend to be increased by high-fat diet. Voluntary running reduced body weight and amount of white adipose tissue in LDLR(-/-) mice. Endothelial dysfunction in LDLR(-/-) mice could not be improved by voluntary running. In a clinical context, physical exercise alone might not have an influence on functional parameters and LDL-C levels in patients with familial hypercholesterolemia. However, physical activity in these patients may be in general beneficial and should be performed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Femtosecond laser cutting of endothelial grafts: comparison of endothelial and epithelial applanation.

    Science.gov (United States)

    Bernard, Aurélien; He, Zhiguo; Gauthier, Anne Sophie; Trone, Marie Caroline; Baubeau, Emmanuel; Forest, Fabien; Dumollard, Jean Marc; Peocʼh, Michel; Thuret, Gilles; Gain, Philippe

    2015-02-01

    Stromal surface quality of endothelial lamellae cut for endothelial keratoplasty with a femtosecond laser (FSL) with epithelial applanation remains disappointing. Applanation of the endothelial side of the cornea, mounted inverted on an artificial chamber, has therefore been proposed to improve cut quality. We compared lamellar quality after FSL cutting using epithelial versus endothelial applanation. Lamellae were cut with an FSL from organ-cultured corneas. After randomization, 7 were cut with epithelial applanation and 7 with endothelial applanation. Lamellae of 50-, 75-, and 100-μm thickness were targeted. Thickness was measured by optical coherence tomography before and immediately after cutting. Viable endothelial cell density was quantified immediately after cutting using triple labeling with Hoechst/ethidium/calcein-AM coupled with image analysis with ImageJ. The stromal surface was evaluated by 9 masked observers using semiquantitative scoring of scanning electronic microscopy images. Histology of 2 samples was also analyzed before lamellar detachment. Precision (difference in target/actual thickness) and thickness regularity [coefficient of variation (CV) of 10 measurements] were significantly better with endothelial applanation (precision: 18 μm; range, 10-30; CV: 11%; range, 8-12) than with epithelial applanation (precision: 84 μm; range, 54-107; P = 0.002; CV: 24%; range, 13-47; P = 0.001). Endothelial applanation provided thinner lamellae. However, viable endothelial cell density was significantly lower after endothelial applanation (1183 cells/mm2; range, 787-1725 versus 1688 cells/mm2; range, 1288-2025; P = 0.018). FSL cutting of endothelial lamellae using endothelial applanation provides thinner more regular grafts with more predictable thickness than with conventional epithelial applanation but strongly reduces the pool of viable endothelial cells.

  2. Archetypal sandwich-structured CuO for high performance non-enzymatic sensing of glucose

    Science.gov (United States)

    Meher, Sumanta Kumar; Rao, G. Ranga

    2013-02-01

    In the quest to enhance the selectivity and sensitivity of novel structured metal oxides for electrochemical non-enzymatic sensing of glucose, we report here a green synthesis of unique sandwich-structured CuO on a large scale under microwave mediated homogeneous precipitation conditions. The physicochemical studies carried out by XRD and BET methods show that the monoclinic CuO formed via thermal decomposition of Cu2(OH)2CO3 possesses monomodal channel-type pores with largely improved surface area (~43 m2 g-1) and pore volume (0.163 cm3 g-1). The fascinating surface morphology and pore structure of CuO is formulated due to homogeneous crystallization and microwave induced self assembly during synthesis. The cyclic voltammetry and chronoamperometry studies show diffusion controlled glucose oxidation at ~0.6 V (vs. Ag/AgCl) with extremely high sensitivity of 5342.8 μA mM-1 cm-2 and respective detection limit and response time of ~1 μM and ~0.7 s, under a wide dynamic concentration range of glucose. The chronoamperometry measurements demonstrate that the sensitivity of CuO to glucose is unaffected by the absence of dissolved oxygen and presence of poisoning chloride ions in the reaction medium, which essentially implies high poison resistance activity of the sandwich-structured CuO. The sandwich-structured CuO also shows insignificant interference/significant selectivity to glucose, even in the presence of high concentrations of other sugars as well as reducing species. In addition, the sandwich-structured CuO shows excellent reproducibility (relative standard deviation of ~2.4% over ten identically fabricated electrodes) and outstanding long term stability (only ~1.3% loss in sensitivity over a period of one month) during non-enzymatic electrochemical sensing of glucose. The unique microstructure and suitable channel-type pore architecture provide structural stability and maximum accessible electroactive surface for unimpeded mobility of glucose as well as the

  3. Efficacy of functional foods mixture in improving hypercholesterolemia, inflammatory and endothelial dysfunction biomarkers-induced by high cholesterol diet.

    Science.gov (United States)

    Al-Muzafar, Hessah Mohammed; Amin, Kamal Adel

    2017-10-06

    Hypercholesterolemia associated with cardiovascular diseases is a global health issue that could be alleviated by functional foods. This study aimed to explore the effects of a high-cholesterol diet on lipid profile, cardiac, inflammatory, and endothelial dysfunction biomarkers, and the possible improvement by functional foods mixture. Male albino rats weighing 100-150 g were randomly divided into four equal groups: 1st control, giving a normal diet; the 2nd received high-cholesterol diet for 8 weeks, the 3rd received the high-cholesterol diet + functional foods mixture, and the 4th administered high-cholesterol diet +atorvastatin (20 mg) orally. The results showed a significant increase in lipid profile and cardiac biomarkers levels (lactate dehydrogenase, creatine kinase and homocystein), also inflammatory markers, as, tumor necrotic factor alpha and chronic reactive proteins were elevated, moreover, vascular adhesion molecule-1 and nitric oxide synthase were disturbed in high-cholesterol diet compared with normal group. While administration of atorvastatin and functional foods mixture ameliorated these alterations. Administration of functional foods mixture and atorvastatin were effective in treating hypercholesterolemia, reduce the risk of inflammation and cardiovascular biomarkers with a high safety margin. These efficiencies may be due to its active ingredient that improve the imbalance in the measured biomarkers.

  4. LX4211 increases serum glucagon-like peptide 1 and peptide YY levels by reducing sodium/glucose cotransporter 1 (SGLT1)-mediated absorption of intestinal glucose.

    Science.gov (United States)

    Powell, David R; Smith, Melinda; Greer, Jennifer; Harris, Angela; Zhao, Sharon; DaCosta, Christopher; Mseeh, Faika; Shadoan, Melanie K; Sands, Arthur; Zambrowicz, Brian; Ding, Zhi-Ming

    2013-05-01

    LX4211 [(2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(methylthio)tetrahydro-2H-pyran-3,4,5-triol], a dual sodium/glucose cotransporter 1 (SGLT1) and SGLT2 inhibitor, is thought to decrease both renal glucose reabsorption by inhibiting SGLT2 and intestinal glucose absorption by inhibiting SGLT1. In clinical trials in patients with type 2 diabetes mellitus (T2DM), LX4211 treatment improved glycemic control while increasing circulating levels of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY). To better understand how LX4211 increases GLP-1 and PYY levels, we challenged SGLT1 knockout (-/-) mice, SGLT2-/- mice, and LX4211-treated mice with oral glucose. LX4211-treated mice and SGLT1-/- mice had increased levels of plasma GLP-1, plasma PYY, and intestinal glucose during the 6 hours after a glucose-containing meal, as reflected by area under the curve (AUC) values, whereas SGLT2-/- mice showed no response. LX4211-treated mice and SGLT1-/- mice also had increased GLP-1 AUC values, decreased glucose-dependent insulinotropic polypeptide (GIP) AUC values, and decreased blood glucose excursions during the 6 hours after a challenge with oral glucose alone. However, GLP-1 and GIP levels were not increased in LX4211-treated mice and were decreased in SGLT1-/- mice, 5 minutes after oral glucose, consistent with studies linking decreased intestinal SGLT1 activity with reduced GLP-1 and GIP levels 5 minutes after oral glucose. These data suggest that LX4211 reduces intestinal glucose absorption by inhibiting SGLT1, resulting in net increases in GLP-1 and PYY release and decreases in GIP release and blood glucose excursions. The ability to inhibit both intestinal SGLT1 and renal SGLT2 provides LX4211 with a novel dual mechanism of action for improving glycemic control in patients with T2DM.

  5. Hyperglycemia (High Blood Glucose)

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  6. Hyperglycemia (High Blood Glucose)

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  7. Proanthocyanidins Prevent High Glucose-Induced Eye Malformation by Restoring Pax6 Expression in Chick Embryo

    Directory of Open Access Journals (Sweden)

    Rui-Rong Tan

    2015-08-01

    Full Text Available Gestational diabetes mellitus (GDM is one of the leading causes of offspring malformations, in which eye malformation is an important disease. It has raised demand for therapy to improve fetal outcomes. In this study, we used chick embryo to establish a GDM model to study the protective effects of proanthocyanidins on eye development. Chick embryos were exposed to high glucose (0.2 mmol/egg on embryo development day (EDD 1. Proanthocyanidins (1 and 10 nmol/egg were injected into the air sac on EDD 0. Results showed that both dosages of proanthocyanidins could prevent the eye malformation and rescue the high glucose-induced oxidative stress significantly, which the similar effects were showed in edaravone. However, proanthocyanidins could not decrease the glucose concentration of embryo eye. Moreover, the key genes regulating eye development, Pax6, was down-regulated by high glucose. Proanthocyanidins could restore the suppressed expression of Pax6. These results indicated proanthocyanidins might be a promising natural agent to prevent high glucose-induced eye malformation by restoring Pax6 expression.

  8. Influence of corn steep liquor and glucose on colonization of control and CCB (Cu/Cr/B)-treated wood by brown rot fungi

    International Nuclear Information System (INIS)

    Humar, Miha; Amartey, Sam A.; Pohleven, Franc

    2006-01-01

    There are increasing problems with regard to the disposal of treated wood waste. Due to heavy metals or arsenic in impregnated wood waste, burning and landfill disposal options are not considered to be environmentally friendly solutions for dealing with this problem. Extraction of the heavy metals and recycling of the preservatives from the wood waste is a much more promising and environmentally friendly solution. In order to study the scale up of this process, copper/chromium/boron-treated wood specimens were exposed to copper tolerant (Antrodia vaillantii and Leucogyrophana pinastri) and copper sensitive wood decay fungi (Gloeophyllum trabeum and Poria monticola). Afterwards, the ability of fungal hyphae to penetrate and overgrow the wood specimens was investigated. The fungal growths were stimulated by immersing the specimens into aqueous solution of glucose or corn steep liquor prior to exposure to the fungi. The fastest colonization of the impregnated wood was by the copper tolerant A. vaillantii. Addition of glucose onto the surface of the wood specimens increased the fungi colonization of the specimens; however, immersion of the specimens into the solution of corn steep liquor did not have the same positive influence. These results are important in elucidating copper toxicity in wood decay fungi and for using these fungi for bioremediation of treated wood wastes

  9. A diet based on high-heat-treated foods promotes risk factors for diabetes mellitus and cardiovascular diseases.

    Science.gov (United States)

    Birlouez-Aragon, Inès; Saavedra, Giselle; Tessier, Frédéric J; Galinier, Anne; Ait-Ameur, Lamia; Lacoste, Florence; Niamba, Claude-Narcisse; Alt, Nadja; Somoza, Veronika; Lecerf, Jean-Michel

    2010-05-01

    The modern Western lifestyle is characterized by the consumption of high-heat-treated foods because of their characteristic taste and flavor. However, it has been shown that treating food at high temperatures can generate potentially harmful compounds that promote inflammation and cardiovascular disease in subjects with diabetes. The aim of this study was to determine whether high-heat-treated foods also pose a risk for healthy subjects. A randomized, crossover, diet-controlled intervention trial with 62 volunteers was designed to compare the potential metabolic effects of 2 diets, one that was based on mild steam cooking and another that was based on high-temperature cooking. These 2 diets differed mainly in their contents of Maillard reaction products (MRPs). MRPs were assessed in the diet and in subjects' feces, blood, and urine samples, with N(epsilon)-carboxymethyllysine as an indicator of MRPs. Biological indicators of glucose and lipid metabolism as well as oxidative stress were analyzed in subjects after 1 mo on each diet. In comparison with the steamed diet, 1 mo of consuming the high-heat-treated diet induced significantly lower insulin sensitivity and plasma concentrations of long-chain n-3 (omega-3) fatty acids and vitamins C and E [-17% (P markers associated with an enhanced risk of type 2 diabetes and cardiovascular diseases in healthy people. Replacing high-heat-treatment techniques by mild cooking techniques may help to positively modulate biomarkers associated with an increased risk of diabetes mellitus and cardiovascular diseases.

  10. Annexin A1 N-terminal derived peptide Ac2-26 stimulates fibroblast migration in high glucose conditions.

    Directory of Open Access Journals (Sweden)

    Valentina Bizzarro

    Full Text Available Deficient wound healing in diabetic patients is very frequent, but the cellular and molecular causes are poorly defined. In this study, we have evaluated whether Annexin A1 derived peptide Ac2-26 stimulates fibroblast migration in high glucose conditions. Using normal human skin fibroblasts WS1 in low glucose (LG or high glucose (HG we observed the enrichment of Annexin A1 protein at cell movement structures like lamellipodial extrusions and interestingly, a significant decrease in levels of the protein in HG conditions. The analysis of the translocation of Annexin A1 to cell membrane showed lower levels of Annexin A1 in both membrane pool and supernatants of WS1 cells treated with HG. Wound-healing assays using cell line transfected with Annexin A1 siRNAs indicated a slowing down in migration speed of cells suggesting that Annexin A1 has a role in the migration of WS1 cells. In order to analyze the role of extracellular Annexin A1 in cell migration, we have performed wound-healing assays using Ac2-26 showing that peptide was able to increase fibroblast cell migration in HG conditions. Experiments on the mobilization of intracellular calcium and analysis of p-ERK expression confirmed the activity of the FPR1 following stimulation with the peptide Ac2-26. A wound-healing assay on WS1 cells in the presence of the FPR agonist fMLP, of the FPR antagonist CsH and in the presence of Ac2-26 indicated that Annexin A1 influences fibroblast cell migration under HG conditions acting through FPR receptors whose expression was slightly increased in HG. In conclusion, these data demonstrate that (i Annexin A1 is involved in migration of WS1 cells, through interaction with FPRs; (ii N- terminal peptide of Annexin A1 Ac2-26 is able to stimulate direct migration of WS1 cells in high glucose treatment possibly due to the increased receptor expression observed in hyperglycemia conditions.

  11. Benfotiamine prevents increased β-amyloid production in HEK cells induced by high glucose.

    Science.gov (United States)

    Sun, Xiao-Jing; Zhao, Lei; Zhao, Na; Pan, Xiao-Li; Fei, Guo-Qiang; Jin, Li-Rong; Zhong, Chun-Jiu

    2012-10-01

    To determine whether high glucose enhances β-amyloid (Aβ) production in HEK293 Swedish mutant (APPsw) cells with Aβ precursor protein (APP) overexpression, and whether under this condition benfotiamine reduces the increased Aβ production. HEK293 APPsw cells were cultured with different concentrations of glucose for different times. The Aβ content in the supernatant was determined by ELISA. To investigate the mechanism by which benfotiamine reduced Aβ production, glycogen synthase kinase-3 (GSK-3) activity and expression were measured after the cells were cultured with 5.5 g/L glucose for 12 h. With 1.0, 3.0, 4.5, 5.5, 6.5, 7.5, 8.5, or 10.5 g/L glucose, Aβ production by HEK293 APPsw cells was highest in the presence of 5.5 g/L glucose for 6 and 12 h. The difference in Aβ content between 5.5 and 1.0 g/L was most marked after incubation for 12 h. Benfotiamine at 20 and 40 μg/mL significantly reduced Aβ production in cells incubated with 5.5 g/L glucose for 12 h. Moreover, 40 μg/mL benfotiamine significantly enhanced the ratio of phosphorylated GSK-3 to total GSK-3, together with consistent down-regulation of GSK-3 activity. High glucose increases Aβ production by HEK293 APPsw cells while benfotiamine prevents this increase. This is correlated with the modulation of GSK-3 activity.

  12. ALDH2 Inhibition Potentiates High Glucose Stress-Induced Injury in Cultured Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Guodong Pan

    2016-01-01

    Full Text Available Aldehyde dehydrogenase (ALDH gene superfamily consists of 19 isozymes. They are present in various organs and involved in metabolizing aldehydes that are biologically generated. For instance, ALDH2, a cardiac mitochondrial ALDH isozyme, is known to detoxify 4-hydroxy-2-nonenal, a reactive aldehyde produced upon lipid peroxidation in diabetic conditions. We hypothesized that inhibition of ALDH leads to the accumulation of unmetabolized 4HNE and consequently exacerbates injury in cells subjected to high glucose stress. H9C2 cardiomyocyte cell lines were pretreated with 10 μM disulfiram (DSF, an inhibitor of ALDH2 or vehicle (DMSO for 2 hours, and then subjected to high glucose stress {33 mM D-glucose (HG or 33 mM D-mannitol as an osmotic control (Ctrl} for 24 hrs. The decrease in ALDH2 activity with DSF pretreatment was higher in HG group when compared to Ctrl group. Increased 4HNE adduct formation with DSF pretreatment was higher in HG group compared to Ctrl group. Pretreatment with DSF leads to potentiated HG-induced cell death in cultured H9C2 cardiomyocytes by lowering mitochondrial membrane potential. Our results indicate that ALDH2 activity is important in preventing high glucose induced cellular dysfunction.

  13. Effects of high glucose and thiamine on the balance between matrix metalloproteinases and their tissue inhibitors in vascular cells.

    Science.gov (United States)

    Tarallo, Sonia; Beltramo, Elena; Berrone, Elena; Dentelli, Patrizia; Porta, Massimo

    2010-06-01

    Pericyte survival in diabetic retinopathy depends also on interactions with extracellular matrix (ECM) proteins, which are degraded by matrix metalloproteinases (MMP). Elevated glucose influences ECM turnover, through expression of MMP and their tissue inhibitors, TIMP. We reported on reduced pericyte adhesion to high glucose-conditioned ECM and correction by thiamine. We aimed at verifying the effects of thiamine and benfotiamine on MMP-2, MMP-9 and TIMP expression and activity in human vascular cells with high glucose. In HRP, MMP-2 activity, though not expression, increased with high glucose and decreased with thiamine and benfotiamine; TIMP-1 expression increased with high glucose plus thiamine and benfotiamine; MMP-9 was not expressed. In EC, MMP-9 and MMP-2 expression and activity increased with high glucose, but thiamine and benfotiamine had no effects; TIMP-1 expression was unchanged. Neither glucose nor thiamine modified TIMP-2 and TIMP-3 expression. TIMP-1 concentrations did not change in either HRP or EC. High glucose imbalances MMP/TIMP regulation, leading to increased ECM turnover. Thiamine and benfotiamine correct the increase in MMP-2 activity due to high glucose in HRP, while increasing TIMP-1.

  14. Normal endothelial function in patients with mild-to-moderate psoriasis: a case-control study

    DEFF Research Database (Denmark)

    Jensen, Peter R; Zachariae, Claus; Hansen, Peter

    2011-01-01

    -dependent and technically demanding ultrasound measurement of brachial artery flow-mediated vasodilation. Therefore, we decided to measure endothelial function and other cardiovascular risk factors in patients with mild-to-moderate psoriasis (n = 30) and controls (n = 30) using a newer and relatively operator......Evidence is increasing that severe psoriasis is an independent cardiovascular risk factor. Results from case-control studies of endothelial dysfunction, a marker of early atherosclerosis, in patients with moderate-to-severe psoriasis have been conflicting and were conducted with operator...... blood pressures, and plasma levels of triglycerides, very-low-density lipoprotein cholesterol and glycated glucose, compared with controls. This indicates that even mild-to-moderate psoriasis may be regarded as a systemic inflammatory disease, and that an increased risk of cardiovascular morbidity may...

  15. Human endothelial progenitor cells internalize high-density lipoprotein.

    Directory of Open Access Journals (Sweden)

    Kaemisa Srisen

    Full Text Available Endothelial progenitor cells (EPCs originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL, and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate, cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal

  16. Hyperglycemia (High Blood Glucose)

    Medline Plus

    Full Text Available ... Complications DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & Care Blood Glucose Testing ... Pinterest Youtube Instagram Diabetes Stops Here Blog Online Community Site ... Day Prediabetes My Health Advisor Tools to Know Your Risk Diabetes Basics ...

  17. Hyperuricemia Is a Risk Factor for the Onset of Impaired Fasting Glucose in Men with a High Plasma Glucose Level: A Community-Based Study

    Science.gov (United States)

    Miyake, Teruki; Kumagi, Teru; Furukawa, Shinya; Hirooka, Masashi; Kawasaki, Keitarou; Koizumi, Mitsuhito; Todo, Yasuhiko; Yamamoto, Shin; Abe, Masanori; Kitai, Kohichiro; Matsuura, Bunzo; Hiasa, Yoichi

    2014-01-01

    Background It is not clear whether elevated uric acid is a risk factor for the onset of impaired fasting glucose after stratifying by baseline fasting plasma glucose levels. We conducted a community-based retrospective longitudinal cohort study to clarify the relationship between uric acid levels and the onset of impaired fasting glucose, according to baseline fasting plasma glucose levels. Methods We enrolled 6,403 persons (3,194 men and 3,209 women), each of whom was 18–80 years old and had >2 annual check-ups during 2003–2010. After excluding persons who had fasting plasma glucose levels ≥6.11 mM and/or were currently taking anti-diabetic agents, the remaining 5,924 subjects were classified into quartiles according to baseline fasting plasma glucose levels. The onset of impaired fasting glucose was defined as fasting plasma glucose ≥6.11 mM during the observation period. Results In the quartile groups, 0.9%, 2.1%, 3.4%, and 20.2% of the men developed impaired fasting glucose, respectively, and 0.1%, 0.3%, 0.5%, and 5.6% of the women developed impaired fasting glucose, respectively (P trend fasting glucose in men with highest-quartile fasting plasma glucose levels (adjusted hazard ratio, 1.003; 95% confidence interval, 1.0001–1.005, P = 0.041). Conclusions Among men with high fasting plasma glucose, hyperuricemia may be independently associated with an elevated risk of developing impaired fasting glucose. PMID:25237894

  18. The Effect of Phloroglucinol, A Component of Ecklonia cava Extract, on Hepatic Glucose Production

    Directory of Open Access Journals (Sweden)

    Ji-Young Yoon

    2017-04-01

    Full Text Available Phloroglucinol is a phenolic compound that is one of the major compounds in Ecklonia cava (brown alga. It has many pharmacological activities, but its anti-diabetic effect is not yet fully explored. In this study, we investigated the effect of phloroglucinol on the control of blood glucose levels and the regulation of hepatic glucose production. Phloroglucinol significantly improved glucose tolerance in male C57BL/6J mice fed a high fat diet (HFD and inhibited glucose production in mouse primary hepatocytes. The expression of phosphoenol pyruvate carboxykinase (PEPCK and glucose-6-phosphatase mRNA and protein (G6Pase, enzymes involved in gluconeogenesis, were inhibited in liver tissue from phloroglucinol-treated mice and in phloroglucinol-treated HepG2 cells. In addition, phloroglucinol treatment increased phosphorylated AMP-activated protein kinase (AMPKα in HepG2 cells. Treatment with compound C, an AMPKα inhibitor, inhibited the increase of phosphorylated AMPKα and the decrease of PEPCK and G6Pase expression caused by phloroglucinol treatment. We conclude that phloroglucinol may inhibit hepatic gluconeogenesis via modulating the AMPKα signaling pathway, and thus lower blood glucose levels.

  19. Effects of 1-Methylnicotinamide (MNA) on Exercise Capacity and Endothelial Response in Diabetic Mice.

    Science.gov (United States)

    Przyborowski, Kamil; Wojewoda, Marta; Sitek, Barbara; Zakrzewska, Agnieszka; Kij, Agnieszka; Wandzel, Krystyna; Zoladz, Jerzy Andrzej; Chlopicki, Stefan

    2015-01-01

    1-Methylnicotinamide (MNA), which was initially considered to be a biologically inactive endogenous metabolite of nicotinamide, has emerged as an anti-thrombotic and anti-inflammatory agent with the capacity to release prostacyclin (PGI2). In the present study, we characterized the effects of MNA on exercise capacity and the endothelial response to exercise in diabetic mice. Eight-week-old db/db mice were untreated or treated with MNA for 4 weeks (100 mg·kg-1), and their exercise capacity as well as NO- and PGI2-dependent response to endurance running were subsequently assessed. MNA treatment of db/db mice resulted in four-fold and three-fold elevation of urine concentrations of MNA and its metabolites (Met-2PY + Met-4PY), respectively (P<0.01), but did not affect HbA1c concentration, fasting glucose concentration or lipid profile. However, insulin sensitivity was improved (P<0.01). In MNA-treated db/db mice, the time to fatigue for endurance exercise was significantly prolonged (P<0.05). Post-exercise Δ6-keto-PGF1α (difference between mean concentration in the sedentary and exercised groups) tended to increase, and post-exercise leukocytosis was substantially reduced in MNA-treated animals. In turn, the post-exercise fall in plasma concentration of nitrate was not affected by MNA. In conclusion, we demonstrated for the first time that MNA improves endurance exercise capacity in mice with diabetes, and may also decrease the cardiovascular risk of exercise.

  20. Effects of 1-Methylnicotinamide (MNA on Exercise Capacity and Endothelial Response in Diabetic Mice.

    Directory of Open Access Journals (Sweden)

    Kamil Przyborowski

    Full Text Available 1-Methylnicotinamide (MNA, which was initially considered to be a biologically inactive endogenous metabolite of nicotinamide, has emerged as an anti-thrombotic and anti-inflammatory agent with the capacity to release prostacyclin (PGI2. In the present study, we characterized the effects of MNA on exercise capacity and the endothelial response to exercise in diabetic mice. Eight-week-old db/db mice were untreated or treated with MNA for 4 weeks (100 mg·kg-1, and their exercise capacity as well as NO- and PGI2-dependent response to endurance running were subsequently assessed. MNA treatment of db/db mice resulted in four-fold and three-fold elevation of urine concentrations of MNA and its metabolites (Met-2PY + Met-4PY, respectively (P<0.01, but did not affect HbA1c concentration, fasting glucose concentration or lipid profile. However, insulin sensitivity was improved (P<0.01. In MNA-treated db/db mice, the time to fatigue for endurance exercise was significantly prolonged (P<0.05. Post-exercise Δ6-keto-PGF1α (difference between mean concentration in the sedentary and exercised groups tended to increase, and post-exercise leukocytosis was substantially reduced in MNA-treated animals. In turn, the post-exercise fall in plasma concentration of nitrate was not affected by MNA. In conclusion, we demonstrated for the first time that MNA improves endurance exercise capacity in mice with diabetes, and may also decrease the cardiovascular risk of exercise.

  1. Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet

    International Nuclear Information System (INIS)

    Zhang, Yu-Kun Jennifer; Wu, Kai Connie; Liu, Jie; Klaassen, Curtis D.

    2012-01-01

    Nrf2, a master regulator of intracellular redox homeostasis, is indicated to participate in fatty acid metabolism in liver. However, its role in diet-induced obesity remains controversial. In the current study, genetically engineered Nrf2-null, wild-type (WT), and Nrf2-activated, Keap1-knockdown (K1-KD) mice were fed either a control or a high-fat Western diet (HFD) for 12 weeks. The results indicate that the absence or enhancement of Nrf2 activity did not prevent diet-induced obesity, had limited effects on lipid metabolism, but affected blood glucose homeostasis. Whereas the Nrf2-null mice were resistant to HFD-induced glucose intolerance, the Nrf2-activated K1-KD mice exhibited prolonged elevation of circulating glucose during a glucose tolerance test even on the control diet. Feeding a HFD did not activate the Nrf2 signaling pathway in mouse livers. Fibroblast growth factor 21 (Fgf21) is a liver-derived anti-diabetic hormone that exerts glucose- and lipid-lowering effects. Fgf21 mRNA and protein were both elevated in livers of Nrf2-null mice, and Fgf21 protein was lower in K1-KD mice than WT mice. The inverse correlation between Nrf2 activity and hepatic expression of Fgf21 might explain the improved glucose tolerance in Nrf2-null mice. Furthermore, a more oxidative cellular environment in Nrf2-null mice could affect insulin signaling in liver. For example, mRNA of insulin-like growth factor binding protein 1, a gene repressed by insulin in hepatocytes, was markedly elevated in livers of Nrf2-null mice. In conclusion, genetic alteration of Nrf2 does not prevent diet-induced obesity in mice, but deficiency of Nrf2 improves glucose homeostasis, possibly through its effects on Fgf21 and/or insulin signaling. -- Highlights: ► Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet. ► The anti-diabetic hormone, Fgf21, is highly expressed in livers of Nrf2-null mice. ► The absence of Nrf2 increases the insulin-regulated Igfbp-1 mRNA in liver.

  2. Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Kun Jennifer; Wu, Kai Connie; Liu, Jie; Klaassen, Curtis D., E-mail: cklaasse@kumc.edu

    2012-11-01

    Nrf2, a master regulator of intracellular redox homeostasis, is indicated to participate in fatty acid metabolism in liver. However, its role in diet-induced obesity remains controversial. In the current study, genetically engineered Nrf2-null, wild-type (WT), and Nrf2-activated, Keap1-knockdown (K1-KD) mice were fed either a control or a high-fat Western diet (HFD) for 12 weeks. The results indicate that the absence or enhancement of Nrf2 activity did not prevent diet-induced obesity, had limited effects on lipid metabolism, but affected blood glucose homeostasis. Whereas the Nrf2-null mice were resistant to HFD-induced glucose intolerance, the Nrf2-activated K1-KD mice exhibited prolonged elevation of circulating glucose during a glucose tolerance test even on the control diet. Feeding a HFD did not activate the Nrf2 signaling pathway in mouse livers. Fibroblast growth factor 21 (Fgf21) is a liver-derived anti-diabetic hormone that exerts glucose- and lipid-lowering effects. Fgf21 mRNA and protein were both elevated in livers of Nrf2-null mice, and Fgf21 protein was lower in K1-KD mice than WT mice. The inverse correlation between Nrf2 activity and hepatic expression of Fgf21 might explain the improved glucose tolerance in Nrf2-null mice. Furthermore, a more oxidative cellular environment in Nrf2-null mice could affect insulin signaling in liver. For example, mRNA of insulin-like growth factor binding protein 1, a gene repressed by insulin in hepatocytes, was markedly elevated in livers of Nrf2-null mice. In conclusion, genetic alteration of Nrf2 does not prevent diet-induced obesity in mice, but deficiency of Nrf2 improves glucose homeostasis, possibly through its effects on Fgf21 and/or insulin signaling. -- Highlights: ► Nrf2 deficiency improves glucose tolerance in mice fed a high-fat diet. ► The anti-diabetic hormone, Fgf21, is highly expressed in livers of Nrf2-null mice. ► The absence of Nrf2 increases the insulin-regulated Igfbp-1 mRNA in liver.

  3. Endothelial Activation and Blood-Brain Barrier Disruption in Neurotoxicity after Adoptive Immunotherapy with CD19 CAR-T Cells.

    Science.gov (United States)

    Gust, Juliane; Hay, Kevin A; Hanafi, Laïla-Aïcha; Li, Daniel; Myerson, David; Gonzalez-Cuyar, Luis F; Yeung, Cecilia; Liles, W Conrad; Wurfel, Mark; Lopez, Jose A; Chen, Junmei; Chung, Dominic; Harju-Baker, Susanna; Özpolat, Tahsin; Fink, Kathleen R; Riddell, Stanley R; Maloney, David G; Turtle, Cameron J

    2017-12-01

    Lymphodepletion chemotherapy followed by infusion of CD19-targeted chimeric antigen receptor-modified T (CAR-T) cells can be complicated by neurologic adverse events (AE) in patients with refractory B-cell malignancies. In 133 adults treated with CD19 CAR-T cells, we found that acute lymphoblastic leukemia, high CD19 + cells in bone marrow, high CAR-T cell dose, cytokine release syndrome, and preexisting neurologic comorbidities were associated with increased risk of neurologic AEs. Patients with severe neurotoxicity demonstrated evidence of endothelial activation, including disseminated intravascular coagulation, capillary leak, and increased blood-brain barrier (BBB) permeability. The permeable BBB failed to protect the cerebrospinal fluid from high concentrations of systemic cytokines, including IFNγ, which induced brain vascular pericyte stress and their secretion of endothelium-activating cytokines. Endothelial activation and multifocal vascular disruption were found in the brain of a patient with fatal neurotoxicity. Biomarkers of endothelial activation were higher before treatment in patients who subsequently developed grade ≥4 neurotoxicity. Significance: We provide a detailed clinical, radiologic, and pathologic characterization of neurotoxicity after CD19 CAR-T cells, and identify risk factors for neurotoxicity. We show endothelial dysfunction and increased BBB permeability in neurotoxicity and find that patients with evidence of endothelial activation before lymphodepletion may be at increased risk of neurotoxicity. Cancer Discov; 7(12); 1404-19. ©2017 AACR. See related commentary by Mackall and Miklos, p. 1371 This article is highlighted in the In This Issue feature, p. 1355 . ©2017 American Association for Cancer Research.

  4. Beta Blockers Suppress Dextrose-Induced Endoplasmic Reticulum Stress, Oxidative Stress, and Apoptosis in Human Coronary Artery Endothelial Cells.

    Science.gov (United States)

    Haas, Michael J; Kurban, William; Shah, Harshit; Onstead-Haas, Luisa; Mooradian, Arshag D

    Beta blockers are known to have favorable effects on endothelial function partly because of their capacity to reduce oxidative stress. To determine whether beta blockers can also prevent dextrose-induced endoplasmic reticulum (ER) stress in addition to their antioxidative effects, human coronary artery endothelial cells and hepatocyte-derived HepG2 cells were treated with 27.5 mM dextrose for 24 hours in the presence of carvedilol (a lipophilic beta blockers with alpha blocking activity), propranolol (a lipophilic nonselective beta blockers), and atenolol (a water-soluble selective beta blockers), and ER stress, oxidative, stress and cell death were measured. ER stress was measured using the placental alkaline phosphatase assay and Western blot analysis of glucose regulated protein 78, c-Jun-N-terminal kinase (JNK), phospho-JNK, eukaryotic initiating factor 2α (eIF2α), and phospho-eIF2α and measurement of X-box binding protein 1 (XBP1) mRNA splicing using reverse transcriptase-polymerase chain reaction. Superoxide (SO) generation was measured using the superoxide-reactive probe 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride (MCLA) chemiluminescence. Cell viability was measured by propidium iodide staining method. The ER stress, SO production, and cell death induced by 27.5 mM dextrose were inhibited by all 3 beta blockers tested. The antioxidative and ER stress reducing effects of beta blockers were also observed in HepG2 cells. The salutary effects of beta blockers on endothelial cells in reducing both ER stress and oxidative stress may contribute to the cardioprotective effects of these agents.

  5. Tofogliflozin, a potent and highly specific sodium/glucose cotransporter 2 inhibitor, improves glycemic control in diabetic rats and mice.

    Science.gov (United States)

    Suzuki, Masayuki; Honda, Kiyofumi; Fukazawa, Masanori; Ozawa, Kazuharu; Hagita, Hitoshi; Kawai, Takahiro; Takeda, Minako; Yata, Tatsuo; Kawai, Mio; Fukuzawa, Taku; Kobayashi, Takamitsu; Sato, Tsutomu; Kawabe, Yoshiki; Ikeda, Sachiya

    2012-06-01

    Sodium/glucose cotransporter 2 (SGLT2) is the predominant mediator of renal glucose reabsorption and is an emerging molecular target for the treatment of diabetes. We identified a novel potent and selective SGLT2 inhibitor, tofogliflozin (CSG452), and examined its efficacy and pharmacological properties as an antidiabetic drug. Tofogliflozin competitively inhibited SGLT2 in cells overexpressing SGLT2, and K(i) values for human, rat, and mouse SGLT2 inhibition were 2.9, 14.9, and 6.4 nM, respectively. The selectivity of tofogliflozin toward human SGLT2 versus human SGLT1, SGLT6, and sodium/myo-inositol transporter 1 was the highest among the tested SGLT2 inhibitors under clinical development. Furthermore, no interaction with tofogliflozin was observed in any of a battery of tests examining glucose-related physiological processes, such as glucose uptake, glucose oxidation, glycogen synthesis, hepatic glucose production, glucose-stimulated insulin secretion, and glucosidase reactions. A single oral gavage of tofogliflozin increased renal glucose clearance and lowered the blood glucose level in Zucker diabetic fatty rats. Tofogliflozin also improved postprandial glucose excursion in a meal tolerance test with GK rats. In db/db mice, 4-week tofogliflozin treatment reduced glycated hemoglobin and improved glucose tolerance in the oral glucose tolerance test 4 days after the final administration. No blood glucose reduction was observed in normoglycemic SD rats treated with tofogliflozin. These findings demonstrate that tofogliflozin inhibits SGLT2 in a specific manner, lowers blood glucose levels by increasing renal glucose clearance, and improves pathological conditions of type 2 diabetes with a low hypoglycemic potential.

  6. A high-throughput fluorescence resonance energy transfer (FRET)-based endothelial cell apoptosis assay and its application for screening vascular disrupting agents

    International Nuclear Information System (INIS)

    Zhu, Xiaoming; Fu, Afu; Luo, Kathy Qian

    2012-01-01

    Highlights: ► An endothelial cell apoptosis assay using FRET-based biosensor was developed. ► The fluorescence of the cells changed from green to blue during apoptosis. ► This method was developed into a high-throughput assay in 96-well plates. ► This assay was applied to screen vascular disrupting agents. -- Abstract: In this study, we developed a high-throughput endothelial cell apoptosis assay using a fluorescence resonance energy transfer (FRET)-based biosensor. After exposure to apoptotic inducer UV-irradiation or anticancer drugs such as paclitaxel, the fluorescence of the cells changed from green to blue. We developed this method into a high-throughput assay in 96-well plates by measuring the emission ratio of yellow fluorescent protein (YFP) to cyan fluorescent protein (CFP) to monitor the activation of a key protease, caspase-3, during apoptosis. The Z′ factor for this assay was above 0.5 which indicates that this assay is suitable for a high-throughput analysis. Finally, we applied this functional high-throughput assay for screening vascular disrupting agents (VDA) which could induce endothelial cell apoptosis from our in-house compounds library and dioscin was identified as a hit. As this assay allows real time and sensitive detection of cell apoptosis, it will be a useful tool for monitoring endothelial cell apoptosis in living cell situation and for identifying new VDA candidates via a high-throughput screening.

  7. Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemia.

    Science.gov (United States)

    Grassi, Davide; Desideri, Giovambattista; Necozione, Stefano; Ruggieri, Fabrizio; Blumberg, Jeffrey B; Stornello, Michele; Ferri, Claudio

    2012-09-01

    Nitric oxide plays a pivotal role in regulating vascular tone. Different studies show endothelial function is impaired during hyperglycemia. Dark chocolate increases flow-mediated dilation in healthy and hypertensive subjects with and without glucose intolerance; however, the effect of pretreatment with dark chocolate on endothelial function and other vascular responses to hyperglycemia has not been examined. Therefore, we aimed to investigate the effects of flavanol-rich dark chocolate administration on (1) flow-mediated dilation and wave reflections; (2) blood pressure, endothelin-1 and oxidative stress, before and after oral glucose tolerance test (OGTT). Twelve healthy volunteers (5 males, 28.2±2.7 years) randomly received either 100 g/d dark chocolate or flavanol-free white chocolate for 3 days. After 7 days washout period, volunteers were switched to the other treatment. Flow-mediated dilation, stiffness index, reflection index, peak-to-peak time, blood pressure, endothelin-1 and 8-iso-PGF(2α) were evaluated after each treatment phase and OGTT. Compared with white chocolate, dark chocolate ingestion improved flow-mediated dilation (P=0.03), wave reflections, endothelin-1 and 8-iso-PGF(2α) (Pwave reflections, blood pressure, and endothelin-1 and 8-iso-PGF(2α) increased after OGTT. OGTT causes acute, transient impairment of endothelial function and oxidative stress, which is attenuated by flavanol-rich dark chocolate. These results suggest cocoa flavanols may contribute to vascular health by reducing the postprandial impairment of arterial function associated with the pathogenesis of atherosclerosis.

  8. Modulation of cGMP by human HO-1 retrovirus gene transfer in pulmonary microvessel endothelial cells.

    Science.gov (United States)

    Abraham, Nader G; Quan, Shuo; Mieyal, Paul A; Yang, Liming; Burke-Wolin, Theresa; Mingone, Christopher J; Goodman, Alvin I; Nasjletti, Alberto; Wolin, Michael S

    2002-11-01

    Carbon monoxide (CO) stimulates guanylate cyclase (GC) and increases guanosine 3',5'-cyclic monophosphate (cGMP) levels. We transfected rat-lung pulmonary endothelial cells with a retrovirus-mediated human heme oxygenase (hHO)-1 gene. Pulmonary cells that expressed hHO-1 exhibited a fourfold increase in HO activity associated with decreases in the steady-state levels of heme and cGMP without changes in soluble GC (sGC) and endothelial nitric oxide synthase (NOS) proteins or basal nitrite production. Heme elicited significant increases in CO production and intracellular cGMP levels in both pulmonary endothelial and pulmonary hHO-1-expressing cells. N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NOS, significantly decreased cGMP levels in heme-treated pulmonary endothelial cells but not heme-treated hHO-1-expressing cells. In the presence of exogenous heme, CO and cGMP levels in hHO-1-expressing cells exceeded the corresponding levels in pulmonary endothelial cells. Acute exposure of endothelial cells to SnCl2, which is an inducer of HO-1, increased cGMP levels, whereas chronic exposure decreased heme and cGMP levels. These results indicate that prolonged overexpression of HO-1 ultimately decreases sGC activity by limiting the availability of cellular heme. Heme activates sGC and enhances cGMP levels via a mechanism that is largely insensitive to NOS inhibition.

  9. Effect of docosahexaenoic acid on hippocampal neurons in high-glucose condition: involvement of PI3K/AKT/nuclear factor-κB-mediated inflammatory pathways.

    Science.gov (United States)

    Yang, R-H; Lin, J; Hou, X-H; Cao, R; Yu, F; Liu, H-Q; Ji, A-L; Xu, X-N; Zhang, L; Wang, F

    2014-08-22

    Accumulating evidence suggested that hyperglycemia played a critical role in hippocampus dysfunction in patients with diabetes mellitus. However, the multifactorial pathogenesis of hyperglycemia-induced impairments of hippocampal neurons has not been fully elucidated. Docosahexaenoic acid (DHA) has been shown to enhance learning and memory and affect neural function in various experimental conditions. The present study investigated the effects of DHA on the lipid peroxidation, the level of inflammatory cytokines and neuron apoptosis in the hippocampal neurons in high-glucose condition. High-glucose administration increased the level of tumor necrosis factor α (TNF-α) and IL-6, induced oxidative stress and apoptosis of hippocampal neurons in vitro. DHA treatment reduced oxidative stress and TNF-α expression, protected the hippocampal neurons by increasing AKT phosphorylation and decreasing caspase-3 and caspase-9 expression. These results suggested that high-glucose exposure induced injury of hippocampal neurons in vitro, and the principle mechanisms involved in the neuroprotective effect of DHA were its antioxidant and anti-apoptotic potential. DHA may thus be of use in preventing or treating neuron-degeneration resulting from hyperglycemia. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. A model of type 2 diabetes in the guinea pig using sequential diet-induced glucose intolerance and streptozotocin treatment

    Science.gov (United States)

    Ackart, David F.; Richardson, Michael A.; DiLisio, James E.; Pulford, Bruce; Basaraba, Randall J.

    2017-01-01

    ABSTRACT Type 2 diabetes is a leading cause of morbidity and mortality among noncommunicable diseases, and additional animal models that more closely replicate the pathogenesis of human type 2 diabetes are needed. The goal of this study was to develop a model of type 2 diabetes in guinea pigs, in which diet-induced glucose intolerance precedes β-cell cytotoxicity, two processes that are crucial to the development of human type 2 diabetes. Guinea pigs developed impaired glucose tolerance after 8 weeks of feeding on a high-fat, high-carbohydrate diet, as determined by oral glucose challenge. Diet-induced glucose intolerance was accompanied by β-cell hyperplasia, compensatory hyperinsulinemia, and dyslipidemia with hepatocellular steatosis. Streptozotocin (STZ) treatment alone was ineffective at inducing diabetic hyperglycemia in guinea pigs, which failed to develop sustained glucose intolerance or fasting hyperglycemia and returned to euglycemia within 21 days after treatment. However, when high-fat, high-carbohydrate diet-fed guinea pigs were treated with STZ, glucose intolerance and fasting hyperglycemia persisted beyond 21 days post-STZ treatment. Guinea pigs with diet-induced glucose intolerance subsequently treated with STZ demonstrated an insulin-secretory capacity consistent with insulin-independent diabetes. This insulin-independent state was confirmed by response to oral antihyperglycemic drugs, metformin and glipizide, which resolved glucose intolerance and extended survival compared with guinea pigs with uncontrolled diabetes. In this study, we have developed a model of sequential glucose intolerance and β-cell loss, through high-fat, high-carbohydrate diet and extensive optimization of STZ treatment in the guinea pig, which closely resembles human type 2 diabetes. This model will prove useful in the study of insulin-independent diabetes pathogenesis with or without comorbidities, where the guinea pig serves as a relevant model species. PMID:28093504

  11. A model of type 2 diabetes in the guinea pig using sequential diet-induced glucose intolerance and streptozotocin treatment.

    Science.gov (United States)

    Podell, Brendan K; Ackart, David F; Richardson, Michael A; DiLisio, James E; Pulford, Bruce; Basaraba, Randall J

    2017-02-01

    Type 2 diabetes is a leading cause of morbidity and mortality among noncommunicable diseases, and additional animal models that more closely replicate the pathogenesis of human type 2 diabetes are needed. The goal of this study was to develop a model of type 2 diabetes in guinea pigs, in which diet-induced glucose intolerance precedes β-cell cytotoxicity, two processes that are crucial to the development of human type 2 diabetes. Guinea pigs developed impaired glucose tolerance after 8 weeks of feeding on a high-fat, high-carbohydrate diet, as determined by oral glucose challenge. Diet-induced glucose intolerance was accompanied by β-cell hyperplasia, compensatory hyperinsulinemia, and dyslipidemia with hepatocellular steatosis. Streptozotocin (STZ) treatment alone was ineffective at inducing diabetic hyperglycemia in guinea pigs, which failed to develop sustained glucose intolerance or fasting hyperglycemia and returned to euglycemia within 21 days after treatment. However, when high-fat, high-carbohydrate diet-fed guinea pigs were treated with STZ, glucose intolerance and fasting hyperglycemia persisted beyond 21 days post-STZ treatment. Guinea pigs with diet-induced glucose intolerance subsequently treated with STZ demonstrated an insulin-secretory capacity consistent with insulin-independent diabetes. This insulin-independent state was confirmed by response to oral antihyperglycemic drugs, metformin and glipizide, which resolved glucose intolerance and extended survival compared with guinea pigs with uncontrolled diabetes. In this study, we have developed a model of sequential glucose intolerance and β-cell loss, through high-fat, high-carbohydrate diet and extensive optimization of STZ treatment in the guinea pig, which closely resembles human type 2 diabetes. This model will prove useful in the study of insulin-independent diabetes pathogenesis with or without comorbidities, where the guinea pig serves as a relevant model species. © 2017. Published by

  12. Pioglitazone Improves In Vitro Viability and Function of Endothelial Progenitor Cells from Individuals with Impaired Glucose Tolerance

    Science.gov (United States)

    Spigoni, Valentina; Picconi, Angela; Cito, Monia; Ridolfi, Valentina; Bonomini, Sabrina; Casali, Chiara; Zavaroni, Ivana; Gnudi, Luigi; Metra, Marco; Dei Cas, Alessandra

    2012-01-01

    Background Evidence suggests that the PPARγ-agonist insulin sensitizer pioglitazone, may provide potential beneficial cardiovascular (CV) effects beyond its anti-hyperglycaemic function. A reduced endothelial progenitor cell (EPC) number is associated with impaired glucose tolerance (IGT) or diabetes, conditions characterised by increased CV risk. Aim To evaluate whether pioglitazone can provide benefit in vitro in EPCs obtained from IGT subjects. Materials and Methods Early and late-outgrowth EPCs were obtained from peripheral blood mononuclear cells of 14 IGT subjects. The in vitro effect of pioglitazone (10 µM) with/without PPARγ-antagonist GW9662 (1 µM) was assessed on EPC viability, apoptosis, ability to form tubular-like structures and pro-inflammatory molecule expression. Results Pioglitazone increased early and late-outgrowth EPC viability, with negligible effects on apoptosis. The capacity of EPCs to form tubular-like structures was improved by pioglitazone in early (mean increase 28%; p = 0.005) and late-outgrowth (mean increase 30%; p = 0.037) EPCs. Pioglitazone reduced ICAM-1 and VCAM-1 adhesion molecule expression in both early (p = 0.001 and p = 0.012 respectively) and late-outgrowth (p = 0.047 and p = 0.048, respectively) EPCs. Similarly, pioglitazone reduced TNFα gene and protein expression in both early (p = 0.034;p = 0.022) and late-outgrowth (p = 0.026;p = 0.017) EPCs compared to control. These effects were prevented by incubation with the PPARγ-antagonist GW9662. Conclusion Pioglitazone exerts beneficial effects in vitro on EPCs isolated from IGT subjects, supporting the potential implication of pioglitazone as a CV protective agents. PMID:23139771

  13. Green tea extract with polyethylene glycol-3350 reduces body weight and improves glucose tolerance in db/db and high-fat diet mice.

    Science.gov (United States)

    Park, Jae-Hyung; Choi, Yoon Jung; Kim, Yong Woon; Kim, Sang Pyo; Cho, Ho-Chan; Ahn, Shinbyoung; Bae, Ki-Cheor; Im, Seung-Soon; Bae, Jae-Hoon; Song, Dae-Kyu

    2013-08-01

    Green tea extract (GTE) is regarded to be effective against obesity and type 2 diabetes, but definitive evidences have not been proven. Based on the assumption that the gallated catechins (GCs) in GTE attenuate intestinal glucose and lipid absorption, while enhancing insulin resistance when GCs are present in the circulation through inhibiting cellular glucose uptake in various tissues, this study attempted to block the intestinal absorption of GCs and prolong their residence time in the lumen. We then observed whether GTE containing the nonabsorbable GCs could ameliorate body weight (BW) gain and glucose intolerance in db/db and high-fat diet mice. Inhibition of the intestinal absorption of GCs was accomplished by co-administering the nontoxic polymer polyethylene glycol-3350 (PEG). C57BLKS/J db/db and high-fat diet C57BL/6 mice were treated for 4 weeks with drugs as follows: GTE, PEG, GTE+PEG, voglibose, or pioglitazone. GTE mixed with meals did not have any ameliorating effects on BW gain and glucose intolerance. However, the administration of GTE plus PEG significantly reduced BW gain, insulin resistance, and glucose intolerance, without affecting food intake and appetite. The effect was comparable to the effects of an α-glucosidase inhibitor and a peroxisome proliferator-activated receptor-γ/α agonist. These results indicate that prolonging the action of GCs of GTE in the intestinal lumen and blocking their entry into the circulation may allow GTE to be used as a prevention and treatment for both obesity and obesity-induced type 2 diabetes.

  14. Butter improves glucose tolerance compared with at highly polyunsaturated diet in the rat

    DEFF Research Database (Denmark)

    Hellgren, Lars

    in epidemiological studies, where the typical fatty acid composition of milk-fat, i.e. a high level of saturated fatty acids (SFA) and low concentration of polyunsaturated fatty acids (PUFAs), has been correlated to increased insulin-resistance. It is therefore essential to characterize the impact of milk......-fat on glucose-tolerance in intervention studies. Methods: 16 rats were divided into two groups and fed a semisynthetic diet containing 31 E-% fat, either as butter or highly polyunsaturated grapeseed oil. After 12 weeks on the diets, glucose-tolerance was assayed with the oral-glucose tolerance test (OGTT......). Results and Discussion: The OGTT revealed that the rats on the butter-containing diet, had a substantially higher glucose tolerance than the rats, which were fed grapeseed oil (area under the curve =195  31 mM*min-2 vs. 310  13 mM*min-2, n= 8, p=0.004). There were no differences in serum triacylglycerol...

  15. Ethnic Disparities in Endothelial Function and Its Cardiometabolic Correlates: The Pathobiology of Prediabetes in A Biracial Cohort Study

    Directory of Open Access Journals (Sweden)

    Ibiye Owei

    2018-03-01

    Full Text Available BackgroundEndothelial function (EF reflects the balance between vasodilatory and vasoconstrictive factors produced by (or acting on the innermost lining of blood vessels. Endothelial dysfunction, an imbalance between these factors that favors vasoconstriction, has been associated with increased risk for cardiovascular disease. However, the influence of race/ethnicity and glycemic status on association between EF and cardiovascular risk factors remain to be clarified.Subjects and methodsWe assessed EF in relation to glycemia and cardiometabolic profile in African-American (AA and European-American (EA offspring of parents with type 2 diabetes (T2D, who are participants in the prospective pathobiology and reversibility of prediabetes in a biracial cohort (PROP-ABC study. Assessments at enrollment included a 75 g oral glucose tolerance test (OGTT, blood pressure, anthropometry, body composition (DEXA, and lipid profile. Other assessments were insulin sensitivity and resting energy expenditure. EF was measured using flow-mediated vasodilation (EndoPAT 2000 and expressed as reactive hyperemia index (RHI.ResultsWe studied 190 subjects (100 AA, 90 C, mean age (±SD 53.1 ± 9.1 years, and body mass index 30.6 ± 6.8 kg/m2. Based on OGTT data, 96 subjects (52 AA, 44 EA had prediabetes and 94 subjects were normoglycemic (48 AA and 46 EA. The RHI was lower in AA than EA (2.17 ± 0.55 vs. 2.36 ± 0.72, P = 0.05 and in prediabetic than normoglycemic subjects (2.14 ± 0.62 vs. 2.38 ± 0.65, P = 0.013. Using RHI ≤ 1.68 as diagnostic cut-off, 19% of participants with prediabetes and 10% of normoglycemic participants had endothelial dysfunction (P = 0.04. In univariate models, RHI was positively associated with age and HDL cholesterol levels, and inversely associated with adiposity, diastolic blood pressure, and 2hr plasma glucose. The association between RHI and adiposity was stronger in men than women. The

  16. The SGLT2 Inhibitor Dapagliflozin Significantly Improves the Peripheral Microvascular Endothelial Function in Patients with Uncontrolled Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Sugiyama, Seigo; Jinnouchi, Hideaki; Kurinami, Noboru; Hieshima, Kunio; Yoshida, Akira; Jinnouchi, Katsunori; Nishimura, Hiroyuki; Suzuki, Tomoko; Miyamoto, Fumio; Kajiwara, Keizo; Jinnouchi, Tomio

    2018-03-30

    Objective Sodium-glucose cotransporter-2 (SGLT2) inhibitors reduce cardiovascular events and decrease the body fat mass in patients with type 2 diabetes mellitus (T2DM). We examined whether or not the SGLT2-inhibitor dapagliflozin can improve the endothelial function associated with a reduction in abdominal fat mass. Methods We prospectively recruited patients with uncontrolled (hemoglobin A1c [HbA1c] >7.0%) T2DM who were not being treated by SGLT2 inhibitors. Patients were treated with add-on dapagliflozin (5 mg/day) or non-SGLT2 inhibitor medicines for 6 months to improve their HbA1c. We measured the peripheral microvascular endothelial function as assessed by reactive hyperemia peripheral arterial tonometry (RH-PAT) and calculated the natural logarithmic transformed value of the RH-PAT index (LnRHI). We then investigated changes in the LnRHI and abdominal fat area using computed tomography (CT). Results The subjects were 54 patients with uncontrolled T2DM (72.2% men) with a mean HbA1c of 8.1%. The HbA1c was significantly decreased in both groups, with no significant difference between the groups. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly increased the LnRHI. The changes in the LnRHI were significantly greater in the dapagliflozin group than in the non-SGLT2 inhibitor group. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly decreased the abdominal visceral fat area, subcutaneous fat area (SFA), and total fat area (TFA) as assessed by CT and significantly increased the plasma adiponectin levels. The percentage changes in the LnRHI were significantly correlated with changes in the SFA, TFA, systolic blood pressure, and adiponectin. Conclusion Add-on treatment with dapagliflozin significantly improves the glycemic control and endothelial function associated with a reduction in the abdominal fat mass in patients with uncontrolled T2DM.

  17. Epigenetic regulation of the glucose transporter gene Slc2a1 by β-hydroxybutyrate underlies preferential glucose supply to the brain of fasted mice.

    Science.gov (United States)

    Tanegashima, Kosuke; Sato-Miyata, Yukiko; Funakoshi, Masabumi; Nishito, Yasumasa; Aigaki, Toshiro; Hara, Takahiko

    2017-01-01

    We carried out liquid chromatography-tandem mass spectrometry analysis of metabolites in mice. Those metabolome data showed that hepatic glucose content is reduced, but that brain glucose content is unaffected, during fasting, consistent with the priority given to brain glucose consumption during fasting. The molecular mechanisms for this preferential glucose supply to the brain are not fully understood. We also showed that the fasting-induced production of the ketone body β-hydroxybutyrate (β-OHB) enhances expression of the glucose transporter gene Slc2a1 (Glut1) via histone modification. Upon β-OHB treatment, Slc2a1 expression was up-regulated, with a concomitant increase in H3K9 acetylation at the critical cis-regulatory region of the Slc2a1 gene in brain microvascular endothelial cells and NB2a neuronal cells, shown by quantitative PCR analysis and chromatin immunoprecipitation assay. CRISPR/Cas9-mediated disruption of the Hdac2 gene increased Slc2a1 expression, suggesting that it is one of the responsible histone deacetylases (HDACs). These results confirm that β-OHB is a HDAC inhibitor and show that β-OHB plays an important role in fasting-induced epigenetic activation of a glucose transporter gene in the brain. © 2016 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  18. High volumetric power density, non-enzymatic, glucose fuel cells.

    Science.gov (United States)

    Oncescu, Vlad; Erickson, David

    2013-01-01

    The development of new implantable medical devices has been limited in the past by slow advances in lithium battery technology. Non-enzymatic glucose fuel cells are promising replacement candidates for lithium batteries because of good long-term stability and adequate power density. The devices developed to date however use an "oxygen depletion design" whereby the electrodes are stacked on top of each other leading to low volumetric power density and complicated fabrication protocols. Here we have developed a novel single-layer fuel cell with good performance (2 μW cm⁻²) and stability that can be integrated directly as a coating layer on large implantable devices, or stacked to obtain a high volumetric power density (over 16 μW cm⁻³). This represents the first demonstration of a low volume non-enzymatic fuel cell stack with high power density, greatly increasing the range of applications for non-enzymatic glucose fuel cells.

  19. In vitro induction of protein complexes between bevacizumab, VEGF-A¹⁶⁵ and heparin: explanation for deposits observed on endothelial veins in monkey eyes.

    Science.gov (United States)

    Julien, Sylvie; Biesemeier, Antje; Schraermeyer, Ulrich

    2013-04-01

    By investigating the effects of intravitreal bevacizumab on retinal vessels of monkeys, we found that bevacizumab accumulated locally at high concentration within individual blood vessels. It formed electron-dense fibrous deposits between endothelial cells and erythrocytes or granulocytes inducing retinal vein thrombosis. To better characterise the observed deposits, we investigated in vitro whether these deposits result from a complex between bevacizumab, vascular endothelial growth factor (VEGF)-A(165) and heparin. Cynomolgus monkeys were intravitreally injected with 1.25 mg bevacizumab. The eyes were enucleated between 1 and 14 days after injection and investigated by electron microscopy and immunohistochemistry. Human umbilical vein endothelial cells (HUVEC) were incubated with bevacizumab, VEGF-A(165) and heparin at different concentrations. Treatments with ranibizumab served as control. Bevacizumab and ranibizumab were detected immunohistochemically using Cy-3 or immunogold labelled antibodies. Treated animals showed bevacizumab locally at high concentration within retinal blood vessels. Electron-dense deposits inside retinal vessels and between erythrocytes were detected in three out of four treated monkeys. In vitro, many globular aggregates heavily stained with anti-human IgG were only observed with equimolar amounts (240 nM) of bevacizumab and VEGF-A(165) and 0.2 U/ml heparin and not after ranibizumab treatment. The immunogold labelling specifically localised ultrastructurally the complexes formed between bevacizumab, VEGF-A(165) and heparin at the surfaces of HUVEC cells. Heparin promotes bevacizumab immune complex deposition on to endothelial cells. Our in vitro results could explain the presence of deposits observed on endothelial veins in monkey eyes intravitreally injected with bevacizumab.

  20. Glucoregulation in normal weight schizophrenia patients treated by first generation antipsychotics

    Directory of Open Access Journals (Sweden)

    Marić Nađa

    2008-01-01

    Full Text Available Introduction Schizophrenia patients are at greater risk of obesity, diabetes mellitus (DM, lipid abnormalities and cardiovascular disorders. The metabolic complications in patients are associated with several risk factors: family history of DM, lifestyle, smoking, dietary habits, physical inactivity, but also with antipsychotic medication. In literature, most publications have been focused on the effects of the second generation antipsychotics (SGA on glucose metabolism. However, less attention has been paid to abnormality in glucoregulation, patients with schizophrenia treated with the first generation antipsychotics (FGA. Objective The present study evaluated glucose metabolism in normal weight schizophrenia patients treated with FGA. METHOD The cross-sectional study included 18 patients (FGA treated and 20 healthy controls with neither group differences in sex distribution, age, nor in BMI. Inclusion criteria were normal BMI (20-25 kg/m2. The glucose levels, insulin levels and growth hormone levels during oral glucose tolerance test (OGTT were measured. Results Fasting glucose and insulin levels did not differ significantly between groups. Groups differed in OGTT glucose and insulin peak and area under curve (AUC, level of significance p<0.05 (patients vs. controls: glucose peak 8.3±0.4 vs.6.9±0.5 mmol/l, glucose AUC 758±28 vs. 640±36 mU/l/120 min; insulin peak in patients 92.7±15.6 mU/l; insulin AUC 6060±1016 mU/l/120 min, insulin peak in controls 47.9±6.5 mU/l; insulin AUC 2597±256 mU/l/120 min. Conclusion Patients with schizophrenia, although with normal body mass index, are at high risk of abnormal glucose regulation. Not only SGA increase the risk of impaired glucoregulation and metabolic syndrome, but this may also be due to FGA or schizophrenia per se. .

  1. Therapeutically targeting mitochondrial redox signalling alleviates endothelial dysfunction in preeclampsia.

    Science.gov (United States)

    McCarthy, Cathal; Kenny, Louise C

    2016-09-08

    Aberrant placentation generating placental oxidative stress is proposed to play a critical role in the pathophysiology of preeclampsia. Unfortunately, therapeutic trials of antioxidants have been uniformly disappointing. There is provisional evidence implicating mitochondrial dysfunction as a source of oxidative stress in preeclampsia. Here we provide evidence that mitochondrial reactive oxygen species mediates endothelial dysfunction and establish that directly targeting mitochondrial scavenging may provide a protective role. Human umbilical vein endothelial cells exposed to 3% plasma from women with pregnancies complicated by preeclampsia resulted in a significant decrease in mitochondrial function with a subsequent significant increase in mitochondrial superoxide generation compared to cells exposed to plasma from women with uncomplicated pregnancies. Real-time PCR analysis showed increased expression of inflammatory markers TNF-α, TLR-9 and ICAM-1 respectively in endothelial cells treated with preeclampsia plasma. MitoTempo is a mitochondrial-targeted antioxidant, pre-treatment of cells with MitoTempo protected against hydrogen peroxide-induced cell death. Furthermore MitoTempo significantly reduced mitochondrial superoxide production in cells exposed to preeclampsia plasma by normalising mitochondrial metabolism. MitoTempo significantly altered the inflammatory profile of plasma treated cells. These novel data support a functional role for mitochondrial redox signaling in modulating the pathogenesis of preeclampsia and identifies mitochondrial-targeted antioxidants as potential therapeutic candidates.

  2. Effect of Human Myotubes-Derived Media on Glucose-Stimulated Insulin Secretion

    Directory of Open Access Journals (Sweden)

    Maria L. Mizgier

    2017-01-01

    Full Text Available Fasting to postprandial transition requires a tight adjustment of insulin secretion to its demand, so tissue (e.g., skeletal muscle glucose supply is assured while hypo-/hyperglycemia are prevented. High muscle glucose disposal after meals is pivotal for adapting to increased glycemia and might drive insulin secretion through muscle-released factors (e.g., myokines. We hypothesized that insulin influences myokine secretion and then increases glucose-stimulated insulin secretion (GSIS. In conditioned media from human myotubes incubated with/without insulin (100 nmol/L for 24 h, myokines were qualitatively and quantitatively characterized using an antibody-based array and ELISA-based technology, respectively. C57BL6/J mice islets and Wistar rat beta cells were incubated for 24 h with control and conditioned media from noninsulin- and insulin-treated myotubes prior to GSIS determination. Conditioned media from insulin-treated versus nontreated myotubes had higher RANTES but lower IL6, IL8, and MCP1 concentration. Qualitative analyses revealed that conditioned media from noninsulin- and insulin-treated myotubes expressed 32 and 23 out of 80 myokines, respectively. Islets incubated with conditioned media from noninsulin-treated myotubes had higher GSIS versus control islets (p<0.05. Meanwhile, conditioned media from insulin-treated myotubes did not influence GSIS. In beta cells, GSIS was similar across conditions. In conclusion, factors being present in noninsulin-stimulated muscle cell-derived media appear to influence GSIS in mice islets.

  3. In vitro antioxidant, hypoglycemic and oral glucose tolerance test of banana peels

    Directory of Open Access Journals (Sweden)

    V.V. Navghare

    2017-08-01

    Full Text Available Banana fruit is claimed to have antidiabetic effects despite its high calorie content, and its peels also contain vital phytoconstituents including gallocatechin. Previously banana pulp has been studied for antihyperglycemic effects, and in the present investigation antihyperglycemic effect of ethanolic extract of inner peels of Musa sapientum (EMS, Musa paradisiaca (EMP, Musa cavendish (EMC and Musa acuminata (EMA fruit was evaluated using oral glucose tolerance test in normoglycemic rats. In vitro antioxidant study was conducted using DPPH, H2O2 radical scavenging assay and ferric reducing power assay. Wistar rats were divided into fourteen groups and twelve groups received different doses of aforementioned extracts, while control group received gum acacia solution and remaining group received standard drug, glimepiride. All the rats received glucose load at a dose of 2 g/kg body weight. Groups treated with EMC and EMA showed significant decrease in glucose level (p < 0.01 at 150 min as compared to control group. In hypoglycemic study, only EMP 500 mg/kg, p.o. treated group revealed a significant decrease (p < 0.05 in glucose level at 120 min, while other groups did not show any sign of hypoglycemia. In glucose tolerance test, animals treated with EMC and EMA depicted dose dependent antihyperglycemic effect at 150 min while EMS and EMP showed significant reduction in plasma glucose at higher doses. In a similar fashion, EMA i.e. M. acuminata demonstrated highest antioxidant activity followed by EMC against DPPH radical. In ferric reducing power and H2O2 scavenging assay, EMA demonstrated maximal antioxidant activity when compared with other extracts.

  4. The anti-apoptotic effect of fluid mechanics preconditioning by cells membrane and mitochondria in rats brain microvascular endothelial cells.

    Science.gov (United States)

    Tian, Shan; Zhu, Fengping; Hu, Ruiping; Tian, Song; Chen, Xingxing; Lou, Dan; Cao, Bing; Chen, Qiulei; Li, Bai; Li, Fang; Bai, Yulong; Wu, Yi; Zhu, Yulian

    2018-01-01

    Exercise preconditioning is a simple and effective way to prevent ischemia. This paper further provided the mechanism in hemodynamic aspects at the cellular level. To study the anti-apoptotic effects of fluid mechanics preconditioning, Cultured rats brain microvascular endothelial cells were given fluid intervention in a parallel plate flow chamber before oxygen glucose deprivation. It showed that fluid mechanics preconditioning could inhibit the apoptosis of endothelial cells, and this process might be mediated by the shear stress activation of Tie-2 on cells membrane surface and Bcl-2 on the mitochondria surface. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Indirect induction of endothelial cell injury by PU- or PTFE-mediated activation of monocytes.

    Science.gov (United States)

    Liu, Xin; Xue, Yang; Sun, Jiao

    2010-01-01

    Polyurethanes (PUs) and polytetrafluoroethylene (PTFE) are widely used for making cardiovascular devices, but thrombus formation on the surfaces of these devices is inevitable. Since endothelial injury can lead to thrombosis, most of the studies on PUs or PTFE focused on their damage to endothelial cells. However, few studies have attempted to clarify whether the use of foreign objects as biomaterials can cause endothelial injury by activating the innate immune system. In this study, we aimed to investigate the roles of PU- or PTFE-stimulated immune cells in endothelial-cell injury. First, monocytes (THP-1 cells) were stimulated with PU or PTFE for 24 h and, subsequently, human umbilical vein endothelial cells (HUVECs) were treated with the supernatants of the stimulated cells for 24 h. We measured the generation of intracellular reactive oxygen species (ROS) from THP-1 cells treated with PU and PTFE for 24 h, meanwhile hydrogen dioxide (H(2)O(2)), tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the supernatants were also detected. Then, we assessed the apoptosis rate of the HUVECs and determined the expression of NO, inducible nitric oxide synthase (iNOS), and apoptosis-related proteins (p53, Bax, Bcl-2) in the HUVECs. The results showed that large amounts of ROS and low levels of pro-inflammatory cytokines (TNF-α and IL-1β) were produced by the stimulated THP-1 cells. After culturing with the supernatants of the PU- or PTFE-stimulated THP-1 cells, the apoptosis rate, NO production and expression of iNOS, p53 and Bax in the HUVECs were up-regulated, while Bcl-2 expression was down-regulated. In conclusion, the release of ROS by PU- or PTFE-treated THP-1 cells may induce iNOS expression and cause apoptosis in HUVECs via the p53, Bax and Bcl-2 proteins. These data provide the interesting finding that endothelial injury in the process of biomaterial-induced thrombosis can be initiated through the release of soluble mediators by monocytes.

  6. Long-Term Feeding of Chitosan Ameliorates Glucose and Lipid Metabolism in a High-Fructose-Diet-Impaired Rat Model of Glucose Tolerance

    Directory of Open Access Journals (Sweden)

    Shing-Hwa Liu

    2015-12-01

    Full Text Available This study was designed to investigate the effects of long-term feeding of chitosan on plasma glucose and lipids in rats fed a high-fructose (HF diet (63.1%. Male Sprague-Dawley rats aged seven weeks were used as experimental animals. Rats were divided into three groups: (1 normal group (normal; (2 HF group; (3 chitosan + HF group (HF + C. The rats were fed the experimental diets and drinking water ad libitum for 21 weeks. The results showed that chitosan (average molecular weight was about 3.8 × 105 Dalton and degree of deacetylation was about 89.8% significantly decreased body weight, paraepididymal fat mass, and retroperitoneal fat mass weight, but elevated the lipolysis rate in retroperitoneal fats of HF diet-fed rats. Supplementation of chitosan causes a decrease in plasma insulin, tumor necrosis factor (TNF-α, Interleukin (IL-6, and leptin, and an increase in plasma adiponectin. The HF diet increased hepatic lipids. However, intake of chitosan reduced the accumulation of hepatic lipids, including total cholesterol (TC and triglyceride (TG contents. In addition, chitosan elevated the excretion of fecal lipids in HF diet-fed rats. Furthermore, chitosan significantly decreased plasma TC, low-density lipoprotein cholesterol (LDL-C, very-low-density lipoprotein cholesterol (VLDL-C, the TC/high-density lipoprotein cholesterol (HDL-C ratio, and increased the HDL-C/(LDL-C + VLDL-C ratio, but elevated the plasma TG and free fatty acids concentrations in HF diet-fed rats. Plasma angiopoietin-like 4 (ANGPTL4 protein expression was not affected by the HF diet, but it was significantly increased in chitosan-supplemented, HF-diet-fed rats. The high-fructose diet induced an increase in plasma glucose and impaired glucose tolerance, but chitosan supplementation decreased plasma glucose and improved impairment of glucose tolerance and insulin tolerance. Taken together, these results indicate that supplementation with chitosan can improve the impairment

  7. Activation of Endothelial Nitric Oxide (eNOS Occurs through Different Membrane Domains in Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Jason Tran

    Full Text Available Endothelial cells respond to a large range of stimuli including circulating lipoproteins, growth factors and changes in haemodynamic mechanical forces to regulate the activity of endothelial nitric oxide synthase (eNOS and maintain blood pressure. While many signalling pathways have been mapped, the identities of membrane domains through which these signals are transmitted are less well characterized. Here, we manipulated bovine aortic endothelial cells (BAEC with cholesterol and the oxysterol 7-ketocholesterol (7KC. Using a range of microscopy techniques including confocal, 2-photon, super-resolution and electron microscopy, we found that sterol enrichment had differential effects on eNOS and caveolin-1 (Cav1 colocalisation, membrane order of the plasma membrane, caveolae numbers and Cav1 clustering. We found a correlation between cholesterol-induced condensation of the plasma membrane and enhanced high density lipoprotein (HDL-induced eNOS activity and phosphorylation suggesting that cholesterol domains, but not individual caveolae, mediate HDL stimulation of eNOS. Vascular endothelial growth factor (VEGF-induced and shear stress-induced eNOS activity was relatively independent of membrane order and may be predominantly controlled by the number of caveolae on the cell surface. Taken together, our data suggest that signals that activate and phosphorylate eNOS are transmitted through distinct membrane domains in endothelial cells.

  8. Cellular redox homeostasis in endothelial cells treated with nonmodified and Fenton-modified nanodiamond powders.

    Science.gov (United States)

    Solarska-Ściuk, K; Gajewska, A; Skolimowski, J; Gajek, A; Bartosz, G

    2014-01-01

    Diamond nanoparticles find numerous applications in pharmacy, medicine, cosmetics, and biotechnology. However, possible adverse cellular effects of diamond nanoparticle cells have been reported, which may limit their use. The aim of this study was to compare the effect of nonmodified diamond nanoparticles (D) and diamond nanoparticles modified by the Fenton reaction (D+OH) on human umbilical cord endothelial cells (HUVEC-ST). We found that both D and D+OH show time- and concentration-dependent cytotoxicity, inducing apoptosis and necrosis of HUVEC-ST. Interaction with D and D+OH also induced changes in the production of reactive oxygen and nitrogen species and changes in the level of glutathione and activities of antioxidant enzymes in the cells. These data demonstrate that diamond nanoparticles may induce oxidative stress in human endothelial cells, which contributes to their cytotoxic effects seen at higher concentrations of D and D+OH. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  9. ZnO nanowire-based glucose biosensors with different coupling agents

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Juneui [Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Lim, Sangwoo, E-mail: swlim@yonsei.ac.kr [Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Fabrication of ZnO nanowire-based glucose biosensors using different coupling agents. Black-Right-Pointing-Pointer Highest sensitivity for (3-aminopropyl)methyldiethoxysilane-treated biosensor. Black-Right-Pointing-Pointer Larger amount of glucose oxidase and lower electron transfer resistance for (3-aminopropyl)methyldiethoxysilane-treated biosensor. - Abstract: ZnO-nanowire-based glucose biosensors were fabricated by immobilizing glucose oxidase (GOx) onto a linker attached to ZnO nanowires. Different coupling agents were used, namely (3-aminopropyl)trimethoxysilane (APTMS), (3-aminopropyl)triethoxysilane (APTES), and (3-aminopropyl)methyldiethoxysilane (APS), to increase the affinity of GOx binding to ZnO nanowires. The amount of GOx immobilized on the ZnO nanowires, the performance, sensitivity, and Michaelis-Menten constant of each biosensor, and the electron transfer resistance through the biosensor were all measured in order to investigate the effect of the coupling agent on the ZnO nanowire-based biosensor. Among the different biosensors, the APS-treated biosensor had the highest sensitivity (17.72 {mu}A cm{sup -2} mM{sup -1}) and the lowest Michaelis-Menten constant (1.37 mM). Since APS-treated ZnO nanowires showed the largest number of C-N groups and the lowest electron transfer resistance through the biosensor, we concluded that these properties were the key factors in the performance of APS-treated glucose biosensors.

  10. ZnO nanowire-based glucose biosensors with different coupling agents

    International Nuclear Information System (INIS)

    Jung, Juneui; Lim, Sangwoo

    2013-01-01

    Highlights: ► Fabrication of ZnO nanowire-based glucose biosensors using different coupling agents. ► Highest sensitivity for (3-aminopropyl)methyldiethoxysilane-treated biosensor. ► Larger amount of glucose oxidase and lower electron transfer resistance for (3-aminopropyl)methyldiethoxysilane-treated biosensor. - Abstract: ZnO-nanowire-based glucose biosensors were fabricated by immobilizing glucose oxidase (GOx) onto a linker attached to ZnO nanowires. Different coupling agents were used, namely (3-aminopropyl)trimethoxysilane (APTMS), (3-aminopropyl)triethoxysilane (APTES), and (3-aminopropyl)methyldiethoxysilane (APS), to increase the affinity of GOx binding to ZnO nanowires. The amount of GOx immobilized on the ZnO nanowires, the performance, sensitivity, and Michaelis–Menten constant of each biosensor, and the electron transfer resistance through the biosensor were all measured in order to investigate the effect of the coupling agent on the ZnO nanowire-based biosensor. Among the different biosensors, the APS-treated biosensor had the highest sensitivity (17.72 μA cm −2 mM −1 ) and the lowest Michaelis–Menten constant (1.37 mM). Since APS-treated ZnO nanowires showed the largest number of C-N groups and the lowest electron transfer resistance through the biosensor, we concluded that these properties were the key factors in the performance of APS-treated glucose biosensors.

  11. Agmatine ameliorates atherosclerosis progression and endothelial dysfunction in high cholesterol-fed rabbits.

    Science.gov (United States)

    El-Awady, Mohammed S; Suddek, Ghada M

    2014-06-01

    The aim of this work was to explore possible effects of agmatine, an endogenous inhibitor of inducible nitric oxide synthase (iNOS), against hypercholesterolemia-induced lipid profile changes and endothelial dysfunction. Hypercholesterolemia was induced by feeding rabbits with a high-cholesterol diet (HCD, 0.5%) for 8 weeks. Another HCD-fed group was orally administered agmatine (10 mg/kg/day) during weeks 5 through 8. Serum lipid profile, malondialdehyde (MDA), nitric oxide (NO) and lactate dehydrogenase (LDH) were determined. Aorta was isolated to analyse vascular reactivity, atherosclerotic lesions and intima/media (I/M) ratio. HCD induced a significant increase in serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides and high-density lipoprotein cholesterol (HDL-C). Agmatine administration significantly decreased HCD-induced elevations in serum TC and LDL-C, MDA, LDH and NO while significantly increased HDL-C levels. Additionally, agmatine significantly protected against HCD-induced attenuation of rabbit aortic endothelium-dependent relaxation to acetylcholine. HCD and agmatine did not significantly influence aortic endothelium-independent relaxation to sodium nitroprusside. Moreover, agmatine significantly reduced the elevation in aortic atherosclerotic lesion area and I/M ratio. This study is the first to reveal that agmatine has the ability to ameliorate hypercholesterolemia-induced lipemic-oxidative and endothelial function injuries possibly by its antioxidant potential and/or iNOS inhibition. © 2014 Royal Pharmaceutical Society.

  12. High glucose induces inflammatory cytokine through protein kinase C-induced toll-like receptor 2 pathway in gingival fibroblasts

    International Nuclear Information System (INIS)

    Jiang, Shao-Yun; Wei, Cong-Cong; Shang, Ting-Ting; Lian, Qi; Wu, Chen-Xuan; Deng, Jia-Yin

    2012-01-01

    Highlights: ► High glucose significantly induced TLR2 expression in gingival fibroblasts. ► High glucose increased NF-κB p65 nuclear activity, IL-1β and TNF-α levels. ► PKC-α/δ-TLR2 pathway is involved in periodontal inflammation under high glucose. -- Abstract: Toll-like receptors (TLRs) play a key role in innate immune response and inflammation, especially in periodontitis. Meanwhile, hyperglycemia can induce inflammation in diabetes complications. However, the activity of TLRs in periodontitis complicated with hyperglycemia is still unclear. In the present study, high glucose (25 mmol/l) significantly induced TLR2 expression in gingival fibroblasts (p < 0.05). Also, high glucose increased nuclear factor kappa B (NF-κB) p65 nuclear activity, tumor necrosis factor-α (TNF-α) and interleukin-lβ (IL-1β) levels. Protein kinase C (PKC)-α and δ knockdown with siRNA significantly decreased TLR2 and NF-κB p65 expression (p < 0.05), whereas inhibition of PKC-β had no effect on TLR2 and NF-κB p65 under high glucose (p < 0.05). Additional studies revealed that TLR2 knockdown significantly abrogated high-glucose-induced NF-κB expression and inflammatory cytokine secretion. Collectively, these data suggest that high glucose stimulates TNF-α and IL-1β secretion via inducing TLR2 through PKC-α and PKC-δ in human gingival fibroblasts.

  13. High glucose induces inflammatory cytokine through protein kinase C-induced toll-like receptor 2 pathway in gingival fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Shao-Yun, E-mail: jiangshaoyun@yahoo.com [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Heping District, Tianjin 300070 (China); Wei, Cong-Cong; Shang, Ting-Ting; Lian, Qi; Wu, Chen-Xuan [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Heping District, Tianjin 300070 (China); Deng, Jia-Yin, E-mail: yazhou2991@126.com [School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Heping District, Tianjin 300070 (China)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer High glucose significantly induced TLR2 expression in gingival fibroblasts. Black-Right-Pointing-Pointer High glucose increased NF-{kappa}B p65 nuclear activity, IL-1{beta} and TNF-{alpha} levels. Black-Right-Pointing-Pointer PKC-{alpha}/{delta}-TLR2 pathway is involved in periodontal inflammation under high glucose. -- Abstract: Toll-like receptors (TLRs) play a key role in innate immune response and inflammation, especially in periodontitis. Meanwhile, hyperglycemia can induce inflammation in diabetes complications. However, the activity of TLRs in periodontitis complicated with hyperglycemia is still unclear. In the present study, high glucose (25 mmol/l) significantly induced TLR2 expression in gingival fibroblasts (p < 0.05). Also, high glucose increased nuclear factor kappa B (NF-{kappa}B) p65 nuclear activity, tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-l{beta} (IL-1{beta}) levels. Protein kinase C (PKC)-{alpha} and {delta} knockdown with siRNA significantly decreased TLR2 and NF-{kappa}B p65 expression (p < 0.05), whereas inhibition of PKC-{beta} had no effect on TLR2 and NF-{kappa}B p65 under high glucose (p < 0.05). Additional studies revealed that TLR2 knockdown significantly abrogated high-glucose-induced NF-{kappa}B expression and inflammatory cytokine secretion. Collectively, these data suggest that high glucose stimulates TNF-{alpha} and IL-1{beta} secretion via inducing TLR2 through PKC-{alpha} and PKC-{delta} in human gingival fibroblasts.

  14. High glucose induces activation of NF-κB inflammatory signaling through IκBα sumoylation in rat mesangial cells

    International Nuclear Information System (INIS)

    Huang, Wei; Xu, Ling; Zhou, Xueqin; Gao, Chenlin; Yang, Maojun; Chen, Guo; Zhu, Jianhua; Jiang, Lan; Gan, Huakui; Gou, Fang; Feng, Hong; Peng, Juan; Xu, Yong

    2013-01-01

    Highlights: •The expression of SUMO1, SUMO2/3 under high glucose was obviously enhanced. •High glucose induced degradation of IκBα and activation of NF-κB pathway. •Sumoylation of IκBα in high glucose were significantly decreased. •The proteasome inhibitor MG132 could partially revert the degradation of IκBα. -- Abstract: The posttranslational modification of proteins by small ubiquitin-like modifiers (SUMOs) has emerged as an important regulatory mechanism for the alteration of protein activity, stability, and cellular localization. The latest research demonstrates that sumoylation is extensively involved in the regulation of the nuclear factor κB (NF-κB) pathway, which plays a critical role in the regulation of inflammation and contributes to fibrosis in diabetic nephropathy (DN). However, the role of sumoylation in the regulation of NF-κB signaling in DN is still unclear. In the present study, we cultured rat glomerular mesangial cells (GMCs) stimulated by high glucose and divided GMCs into six groups: normal glucose group (5.6 mmol/L), high glucose groups (10, 20, and 30 mmol/L), mannitol group (i.e., osmotic control group), and MG132 intervention group (30 mmol/L glucose with MG132, a proteasome inhibitor). The expression of SUMO1, SUMO2/3, IκBα, NF-κBp65, and monocyte chemotactic protein 1 (MCP-1) was measured by Western blot, reverse-transcription polymerase chain reaction, and indirect immunofluorescence laser scanning confocal microscopy. The interaction between SUMO1, SUMO2/3, and IκBα was observed by co-immunoprecipitation. The results showed that the expression of SUMO1 and SUMO2/3 was dose- and time-dependently enhanced by high glucose (p < 0.05). However, the expression of IκBα sumoylation in high glucose was significantly decreased compared with the normal glucose group (p < 0.05). The expression of IκBα was dose- and time-dependently decreased, and NF-κBp65 and MCP-1 were increased under high glucose conditions, which

  15. Differential effect of amylin on endothelial-dependent vasodilation in mesenteric arteries from control and insulin resistant rats.

    Directory of Open Access Journals (Sweden)

    Mariam El Assar

    Full Text Available Insulin resistance (IR is frequently associated with endothelial dysfunction and has been proposed to play a major role in cardiovascular disease (CVD. On the other hand, amylin has long been related to IR. However the role of amylin in the vascular dysfunction associated to IR is not well addressed. Therefore, the aim of the study was to assess the effect of acute treatment with amylin on endothelium-dependent vasodilation of isolated mesenteric arteries from control (CR and insulin resistant (IRR rats and to evaluate the possible mechanisms involved. Five week-old male Wistar rats received 20% D-fructose dissolved in drinking water for 8 weeks and were compared with age-matched CR. Plasmatic levels of glucose, insulin and amylin were measured. Mesenteric microvessels were dissected and mounted in wire myographs to evaluate endothelium-dependent vasodilation to acetylcholine. IRR displayed a significant increase in plasmatic levels of glucose, insulin and amylin and reduced endothelium-dependent relaxation when compared to CR. Acute treatment of mesenteric arteries with r-amylin (40 pM deteriorated endothelium-dependent responses in CR. Amylin-induced reduction of endothelial responses was unaffected by the H2O2 scavenger, catalase, but was prevented by the extracellular superoxide scavenger, superoxide dismutase (SOD or the NADPH oxidase inhibitor (VAS2870. By opposite, amylin failed to further inhibit the impaired relaxation in mesenteric arteries of IRR. SOD, or VAS2870, but not catalase, ameliorated the impairment of endothelium-dependent relaxation in IRR. At concentrations present in insulin resistance conditions, amylin impairs endothelium-dependent vasodilation in mircrovessels from rats with preserved vascular function and low levels of endogenous amylin. In IRR with established endothelial dysfunction and elevated levels of amylin, additional exposure to this peptide has no effect on endothelial vasodilation. Increased superoxide

  16. Tanshinol suppresses endothelial cells apoptosis in mice with atherosclerosis via lncRNA TUG1 up-regulating the expression of miR-26a.

    Science.gov (United States)

    Chen, Chao; Cheng, Guangqing; Yang, Xiaoni; Li, Changsheng; Shi, Ran; Zhao, Ningning

    2016-01-01

    Endothelial cell (EC) apoptosis is a crucial process for the development of atherosclerosis. Tanshinol is reported to protect vascular endothelia and attenuate the formation of atherosclerosis. However, the potential molecule mechanism of the protective role of tanshinol in atherosclerosis need to be further investigated. ApoE(-/-)mice were fed with a high-fat diet and treated with tanshinol to detect the effect of tanshinol on endothelial cells apoptosis with TUNEL staining assay. qRT-PCR and Western blot were performed to examine the expression of TUG1 and miR-26a in endothelial cells. RNA-binding protein immunoprecipitation assay was performed to verify the relationship between TUG1 and miR-26a. It has been shown that tanshinol reduced the aortic atherosclerotic lesion area in the entire aorta and aortic sinus in a concentration dependent manner, and suppressed the endothelial cells apoptosis in ApoE(-/-) mice. We further found that the mRNA level of TUG1 was reduced and the expression of miR-26a was up-regulated by tanshinol in endothelial cells. In addition, TUG1 down-regulated the expression of miR-26a in ECV304 cells. Finally, it was shown that overexpression of TUG1 removed the reversed effect of tanshinol on oxidized low-density lipoprotein (ox-LDL)-induced endothelial cells apoptosis. Taken together, our study reveals that tanshinol could attenuate the endothelial cells apoptosis in atherosclerotic ApoE(-/-) mice. Moreover, low TUG1 expression and high level of miR-26a are associated with the endothelial protecting effect of tanshinol.

  17. Glucose transport in brain - effect of inflammation.

    Science.gov (United States)

    Jurcovicova, J

    2014-01-01

    Glucose is transported across the cell membrane by specific saturable transport system, which includes two types of glucose transporters: 1) sodium dependent glucose transporters (SGLTs) which transport glucose against its concentration gradient and 2) sodium independent glucose transporters (GLUTs), which transport glucose by facilitative diffusion in its concentration gradient. In the brain, both types of transporters are present with different function, affinity, capacity, and tissue distribution. GLUT1 occurs in brain in two isoforms. The more glycosylated GLUT1 is produced in brain microvasculature and ensures glucose transport across the blood brain barrier (BBB). The less glycosylated form is localized in astrocytic end-feet and cell bodies and is not present in axons, neuronal synapses or microglia. Glucose transported to astrocytes by GLUT1 is metabolized to lactate serving to neurons as energy source. Proinflammatory cytokine interleukin (IL)-1β upregulates GLUT1 in endothelial cells and astrocytes, whereas it induces neuronal death in neuronal cell culture. GLUT2 is present in hypothalamic neurons and serves as a glucose sensor in regulation of food intake. In neurons of the hippocampus, GLUT2 is supposed to regulate synaptic activity and neurotransmitter release. GLUT3 is the most abundant glucose transporter in the brain having five times higher transport capacity than GLUT1. It is present in neuropil, mostly in axons and dendrites. Its density and distribution correlate well with the local cerebral glucose demands. GLUT5 is predominantly fructose transporter. In brain, GLUT5 is the only hexose transporter in microglia, whose regulation is not yet clear. It is not present in neurons. GLUT4 and GLUT8 are insulin-regulated glucose transporters in neuronal cell bodies in the cortex and cerebellum, but mainly in the hippocampus and amygdala, where they maintain hippocampus-dependent cognitive functions. Insulin translocates GLUT4 from cytosol to plasma

  18. Growth hormone and IGF-1 deficiency exacerbate high-fat diet-induced endothelial impairment in obese Lewis dwarf rats: implications for vascular aging.

    Science.gov (United States)

    Bailey-Downs, Lora C; Sosnowska, Danuta; Toth, Peter; Mitschelen, Matthew; Gautam, Tripti; Henthorn, Jim C; Ballabh, Praveen; Koller, Akos; Farley, Julie A; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

    2012-06-01

    Previous studies suggest that the age-related decline in circulating growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels significantly contribute to vascular dysfunction in aging by impairing cellular oxidative stress resistance pathways. Obesity in elderly individuals is increasing at alarming rates, and there is evidence suggesting that elderly individuals are more vulnerable to the deleterious cardiovascular effects of obesity than younger individuals. However, the specific mechanisms through which aging, GH/IGF-1 deficiency, and obesity interact to promote the development of cardiovascular disease remain unclear. To test the hypothesis that low circulating GH/IGF-1 levels exacerbate the pro-oxidant and proinflammatory vascular effects of obesity, GH/IGF-1-deficient Lewis dwarf rats and heterozygous control rats were fed either a standard diet or a high-fat diet (HFD) for 7 months. Feeding an HFD resulted in similar relative weight gains and increases in body fat content in Lewis dwarf rats and control rats. HFD-fed Lewis dwarf rats exhibited a relative increase in blood glucose levels, lower insulin, and impaired glucose tolerance as compared with HFD-fed control rats. Analysis of serum cytokine expression signatures indicated that chronic GH/IGF-1 deficiency exacerbates HFD-induced inflammation. GH/IGF-1 deficiency also exacerbated HFD-induced endothelial dysfunction, oxidative stress, and expression of inflammatory markers (tumor necrosis factor-α, ICAM-1) in aortas of Lewis dwarf rats. Overall, our results are consistent with the available clinical and experimental evidence suggesting that GH/IGF-1 deficiency renders the cardiovascular system more vulnerable to the deleterious effects of obesity.

  19. [The role of endothelial cells and endothelial precursor cells in angiogenesis].

    Science.gov (United States)

    Poreba, Małgorzata; Usnarska-Zubkiewicz, Lidia; Kuliczkowski, Kazimierz

    2006-01-01

    Endothelium plays a key role in maintenance of vascular homeostasis in human organism. According to new data endothelial cells and hematopoietic cells have a common precursor in prenatal life--a hemangioblast, which explains the fact of sharing the same determinants on the surface of both type of cells. Circulating endothelial precursors were identified in adults and this suggests that hemangioblasts may be present not only during embriogenesis. In some clinical situations the increased numbers of endothelial cells and endothelial precursors were noted, and especially in patients with neoplastic diseases, which is probably the result of increased angiogenesis. Endothelial precursors are thought to be the promice for therapeutic purposes in future--to increase local angiogenesis.

  20. Exercise training improves in vivo endothelial repair capacity of early endothelial progenitor cells in subjects with metabolic syndrome.

    Science.gov (United States)

    Sonnenschein, Kristina; Horváth, Tibor; Mueller, Maja; Markowski, Andrea; Siegmund, Tina; Jacob, Christian; Drexler, Helmut; Landmesser, Ulf

    2011-06-01

    Endothelial dysfunction and injury are considered to contribute considerably to the development and progression of atherosclerosis. It has been suggested that intense exercise training can increase the number and angiogenic properties of early endothelial progenitor cells (EPCs). However, whether exercise training stimulates the capacity of early EPCs to promote repair of endothelial damage and potential underlying mechanisms remain to be determined. The present study was designed to evaluate the effects of moderate exercise training on in vivo endothelial repair capacity of early EPCs, and their nitric oxide and superoxide production as characterized by electron spin resonance spectroscopy analysis in subjects with metabolic syndrome. Twenty-four subjects with metabolic syndrome were randomized to an 8 weeks exercise training or a control group. Superoxide production and nitric oxide (NO) availability of early EPCs were characterized by using electron spin resonance (ESR) spectroscopy analysis. In vivo endothelial repair capacity of EPCs was examined by transplantation into nude mice with defined carotid endothelial injury. Endothelium-dependent, flow-mediated vasodilation was analysed using high-resolution ultrasound. Importantly, exercise training resulted in a substantially improved in vivo endothelial repair capacity of early EPCs (24.0 vs 12.7%; p exercise training, but not in the control group. Moreover, exercise training reduced superoxide production of EPCs, which was not observed in the control group. The present study suggests for the first time that moderate exercise training increases nitric oxide production of early endothelial progenitor cells and reduces their superoxide production. Importantly, this is associated with a marked beneficial effect on the in vivo endothelial repair capacity of early EPCs in subjects with metabolic syndrome.