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  1. Fenofibrate

    Science.gov (United States)

    ... atherosclerosis) decreases the blood flow and, therefore, the oxygen supply to the heart, brain, and other parts ... to take fenofibrate.tell your doctor if you drink or have ever drunk large amounts of alcohol ...

  2. Fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of LncRNA MEG3

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    Hu, Duanmin [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Su, Cunjin [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Jiang, Min [Department of Breast Surgery, The First Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shen, Yating [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shi, Aiming; Zhao, Fenglun [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Chen, Ruidong [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Shen, Zhu [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Bao, Junjie, E-mail: baojjsdfey@sina.com [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Tang, Wen, E-mail: sztangwen@163.com [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China)

    2016-03-04

    There is still no suitable drug for pancreatic cancer treatment, which is one of the most aggressive human tumors. Maternally expressed gene 3 (MEG3), a LncRNA, has been suggested as a tumor suppressor in a range of human tumors. Studies found fenofibrate exerted anti-tumor roles in various human cancer cell lines. However, its role in pancreatic cancer remains unknown. The present study aimed to explore the impacts of fenofibrate on pancreatic cancer cell lines, and to investigate MEG3 role in its anti-tumor mechanisms. We used MTT assay to determine cells proliferation, genome-wide LncRNA microarray analysis to identify differently expressed LncRNAs, siRNA or pCDNA-MEG3 transfection to interfere or upregulate MEG3 expression, western blot to detect protein levels, real-time PCR to determine MEG3 level. Fenofibrate significantly inhibited proliferation of pancreatic cancer cells, increased MEG3 expression and p53 levels. Moreover, knockdown of MEG3 attenuated cytotoxicity induced by fenofibrate. Furthermore, overexpression of MEG3 induced cells death and increased p53 expression. Our results indicated fenofibrate inhibited pancreatic cancer cells proliferation via activation of p53 mediated by upregulation of MEG3. - Highlights: • We found that fenofibrate suppressed proliferation of pancreatic cancer cells. • We found fenofibrate increased LncRNA-MEG3 expression and p53 level in PANC-1 cells. • Inhibition of MEG3 expression attenuated anti-tumor effects of fenofibrate.

  3. Kaempferol Isolated from Nelumbo nucifera Inhibits Lipid Accumulation and Increases Fatty Acid Oxidation Signaling in Adipocytes.

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    Lee, Bonggi; Kwon, Misung; Choi, Jae Sue; Jeong, Hyoung Oh; Chung, Hae Young; Kim, Hyeung-Rak

    2015-12-01

    Stamens of Nelumbo nucifera Gaertn have been used as a Chinese medicine due to its antioxidant, hypoglycemic, and antiatherogenic activity. However, the effects of kaempferol, a main component of N. nucifera, on obesity are not fully understood. We examined the effect of kaempferol on adipogenesis and fatty acid oxidation signaling pathways in 3T3-L1 adipocytes. Kaempferol reduced cytoplasmic triglyceride (TG) accumulation in dose and time-dependent manners during adipocyte differentiation. Accumulation of TG was rapidly reversed by retrieving kaempferol treatment. Kaempferol broadly decreased mRNA or protein levels of adipogenic transcription factors and their target genes related to lipid accumulation. Kaempferol also suppressed glucose uptake and glucose transporter GLUT4 mRNA expression in adipocytes. Furthermore, protein docking simulation suggests that Kaempferol can directly bind to and activate peroxisome proliferator-activated receptor (PPAR)-α by forming hydrophobic interactions with VAL324, THR279, and LEU321 residues of PPARα. The binding affinity was higher than a well-known PPARα agonist fenofibrate. Consistently, mRNA expression levels of PPARα target genes were increased. Our study indicates while kaempferol inhibits lipogenic transcription factors and lipid accumulation, it may bind to PPARα and stimulate fatty acid oxidation signaling in adipocytes.

  4. Fenofibrate inhibits atrial metabolic remodelling in atrial fibrillation through PPAR-α/sirtuin 1/PGC-1α pathway.

    Science.gov (United States)

    Liu, Guang-Zhong; Hou, Ting-Ting; Yuan, Yue; Hang, Peng-Zhou; Zhao, Jing-Jing; Sun, Li; Zhao, Guan-Qi; Zhao, Jing; Dong, Jing-Mei; Wang, Xiao-Bing; Shi, Hang; Liu, Yong-Wu; Zhou, Jing-Hua; Dong, Zeng-Xiang; Liu, Yang; Zhan, Cheng-Chuang; Li, Yue; Li, Wei-Min

    2016-03-01

    Atrial metabolic remodelling is critical for the process of atrial fibrillation (AF). The PPAR-α/sirtuin 1 /PPAR co-activator α (PGC-1α) pathway plays an important role in maintaining energy metabolism. However, the effect of the PPAR-α agonist fenofibrate on AF is unclear. Therefore, the aim of this study was to determine the effect of fenofibrate on atrial metabolic remodelling in AF and explore its possible mechanisms of action. The expression of metabolic proteins was examined in the left atria of AF patients. Thirty-two rabbits were divided into sham, AF (pacing with 600 beats·min(-1) for 1 week), fenofibrate treated (pretreated with fenofibrate before pacing) and fenofibrate alone treated (for 2 weeks) groups. HL-1 cells were subjected to rapid pacing in the presence or absence of fenofibrate, the PPAR-α antagonist GW6471 or sirtuin 1-specific inhibitor EX527. Metabolic factors, circulating biochemical metabolites, atrial electrophysiology, adenine nucleotide levels and accumulation of glycogen and lipid droplets were assessed. The PPAR-α/sirtuin 1/PGC-1α pathway was significantly inhibited in AF patients and in the rabbit/HL-1 cell models, resulting in a reduction of key downstream metabolic factors; this effect was significantly restored by fenofibrate. Fenofibrate prevented the alterations in circulating biochemical metabolites, reduced the level of adenine nucleotides and accumulation of glycogen and lipid droplets, reversed the shortened atrial effective refractory period and increased risk of AF. Fenofibrate inhibited atrial metabolic remodelling in AF by regulating the PPAR-α/sirtuin 1/PGC-1α pathway. The present study may provide a novel therapeutic strategy for AF. © 2016 The British Pharmacological Society.

  5. Hot topic: Ceramide inhibits insulin sensitivity in primary bovine adipocytes.

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    Rico, J E; Myers, W A; Laub, D J; Davis, A N; Zeng, Q; McFadden, J W

    2018-04-01

    In nonruminants, the sphingolipid ceramide inhibits insulin sensitivity by inactivating protein kinase B (AKT) within the insulin-signaling pathway. We have established that ceramide accrual develops with impaired systemic insulin action in ruminants during the transition from gestation to lactation, dietary palmitic acid supplementation, or controlled nutrient restriction. We hypothesized that ceramide promotes AKT inactivation and antagonizes insulin sensitivity in primary bovine adipocytes. Stromal-vascular cells were grown from bovine adipose tissue explants and cultured in differentiation media. To modify ceramide supply, we treated differentiated adipocytes with (1) myriocin, an inhibitor of de novo ceramide synthesis, or (2) cell-permeable C2:0-ceramide. Insulin-stimulated AKT activation (i.e., phosphorylation) and 2-deoxy-D-[ 3 H]-glucose (2DOG) uptake were measured. Treatment of adipocytes with myriocin consistently decreased concentrations of ceramide, monohexosylceramide, and lactosylceramide. The insulin-stimulated ratio of phosphorylated AKT to total AKT was increased with myriocin but decreased with C2:0-ceramide. Moreover, adipocyte insulin-stimulated 2DOG uptake was decreased with C2:0-ceramide and increased with myriocin. We conclude that ceramide inhibits insulin-stimulated glucose uptake by downregulating AKT activation in primary bovine adipocytes. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. ATF3 represses PPARγ expression and inhibits adipocyte differentiation

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    Jang, Min-Kyung; Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr

    2014-11-07

    Highlights: • ATF3 decrease the expression of PPARγ and its target gene in 3T3-L1 adipocytes. • ATF3 represses the promoter activity of PPARγ2 gene. • ATF/CRE (−1537/−1530) is critical for ATF3-mediated downregulation of PPARγ. • ATF3 binds to the promoter region containing the ATF/CRE. • ER stress inhibits adipocyte differentiation through downregulation of PPARγ by ATF3. - Abstract: Activating transcription factor 3 (ATF3) is a stress-adaptive transcription factor that mediates cellular stress response signaling. We previously reported that ATF3 represses CCAAT/enhancer binding protein α (C/EBPα) expression and inhibits 3T3-L1 adipocyte differentiation. In this study, we explored potential role of ATF3 in negatively regulating peroxisome proliferator activated receptor-γ (PPARγ). ATF3 decreased the expression of PPARγ and its target gene in 3T3-L1 adipocytes. ATF3 also repressed the activity of −2.6 Kb promoter of mouse PPARγ2. Overexpression of PPARγ significantly prevented the ATF3-mediated inhibition of 3T3-L1 differentiation. Transfection studies with 5′ deleted-reporters showed that ATF3 repressed the activity of −2037 bp promoter, whereas it did not affect the activity of −1458 bp promoter, suggesting that ATF3 responsive element is located between the −2037 and −1458. An electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 binds to ATF/CRE site (5′-TGACGTTT-3′) between −1537 and −1530. Mutation of the ATF/CRE site abrogated ATF3-mediated transrepression of the PPARγ2 promoter. Treatment with thapsigargin, endoplasmic reticulum (ER) stress inducer, increased ATF3 expression, whereas it decreased PPARγ expression. ATF3 knockdown significantly blocked the thapsigargin-mediated downregulation of PPARγ expression. Furthermore, overexpression of PPARγ prevented inhibition of 3T3-L1 differentiation by thapsigargin. Collectively, these results suggest that ATF3-mediated

  7. Feed-forward inhibition of androgen receptor activity by glucocorticoid action in human adipocytes.

    Science.gov (United States)

    Hartig, Sean M; He, Bin; Newberg, Justin Y; Ochsner, Scott A; Loose, David S; Lanz, Rainer B; McKenna, Neil J; Buehrer, Benjamin M; McGuire, Sean E; Marcelli, Marco; Mancini, Michael A

    2012-09-21

    We compared transcriptomes of terminally differentiated mouse 3T3-L1 and human adipocytes to identify cell-specific differences. Gene expression and high content analysis (HCA) data identified the androgen receptor (AR) as both expressed and functional, exclusively during early human adipocyte differentiation. The AR agonist dihydrotestosterone (DHT) inhibited human adipocyte maturation by downregulation of adipocyte marker genes, but not in 3T3-L1. It is interesting that AR induction corresponded with dexamethasone activation of the glucocorticoid receptor (GR); however, when exposed to the differentiation cocktail required for adipocyte maturation, AR adopted an antagonist conformation and was transcriptionally repressed. To further explore effectors within the cocktail, we applied an image-based support vector machine (SVM) classification scheme to show that adipocyte differentiation components inhibit AR action. The results demonstrate human adipocyte differentiation, via GR activation, upregulates AR but also inhibits AR transcriptional activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. The PPARα Agonist Fenofibrate Preserves Hippocampal Neurogenesis and Inhibits Microglial Activation After Whole-Brain Irradiation

    International Nuclear Information System (INIS)

    Ramanan, Sriram; Kooshki, Mitra; Zhao Weiling; Hsu, F.-C.; Riddle, David R.; Robbins, Mike E.

    2009-01-01

    Purpose: Whole-brain irradiation (WBI) leads to cognitive impairment months to years after radiation. Numerous studies suggest that decreased hippocampal neurogenesis and microglial activation are involved in the pathogenesis of WBI-induced brain injury. The goal of this study was to investigate whether administration of the peroxisomal proliferator-activated receptor (PPAR) α agonist fenofibrate would prevent the detrimental effect of WBI on hippocampal neurogenesis. Methods and Materials: For this study, 129S1/SvImJ wild-type and PPARα knockout mice that were fed either regular or 0.2% wt/wt fenofibrate-containing chow received either sham irradiation or WBI (10-Gy single dose of 137 Cs γ-rays). Mice were injected intraperitoneally with bromodeoxyuridine to label the surviving cells at 1 month after WBI, and the newborn neurons were counted at 2 months after WBI by use of bromodeoxyuridine/neuronal nuclei double immunofluorescence. Proliferation in the subgranular zone and microglial activation were measured at 1 week and 2 months after WBI by use of Ki-67 and CD68 immunohistochemistry, respectively. Results: Whole-brain irradiation led to a significant decrease in the number of newborn hippocampal neurons 2 months after it was performed. Fenofibrate prevented this decrease by promoting the survival of newborn cells in the dentate gyrus. In addition, fenofibrate treatment was associated with decreased microglial activation in the dentate gyrus after WBI. The neuroprotective effects of fenofibrate were abolished in the knockout mice, indicating a PPARα-dependent mechanism or mechanisms. Conclusions: These data highlight a novel role for PPARα ligands in improving neurogenesis after WBI and offer the promise of improving the quality of life for brain cancer patients receiving radiotherapy.

  9. ATF3 inhibits adipocyte differentiation of 3T3-L1 cells

    International Nuclear Information System (INIS)

    Jang, Min Kyung; Kim, Cho Hee; Seong, Je Kyung; Jung, Myeong Ho

    2012-01-01

    Highlights: ► Overexpression of ATF3 inhibits adipocyte differentiation in 3T3-L1 cells. ► Overexpression of ATF3 represses C/EBPα expression. ► ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. ► ATF3 may play a role in hypoxia-mediated inhibition of adipocyte differentiation. -- Abstract: ATF3 is a stress-adaptive gene that regulates proliferation or apoptosis under stress conditions. However, the role of ATF3 is unknown in adipocyte cells. Therefore, in this study, we investigated the functional role of ATF3 in adipocytes. Both lentivirus-mediated overexpression of ATF3 and stably-overexpressed ATF3 inhibited adipocyte differentiation in 3T3-L1 cells, as revealed by decreased lipid staining with oil red staining and reduction in adipogenic genes. Thapsigargin treatment and overexpression of ATF3 decreased C/EBPα transcript and repressed the activity of the 3.6-kb mouse C/EBPα promoter, demonstrating that ATF3 downregulates C/EBPα expression. Transfection studies using mutant constructs containing 5′-deletions in the C/EBPα promoter revealed that a putative ATF/CRE element, GGATGTCA, is located between −1921 and −1914. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. Both chemical hypoxia-mimetics or physical hypoxia led to reduce the C/EBPα mRNA and repress the promoter activity of the C/EBPα gene, whereas increase ATF3 mRNA, suggesting that ATF3 may contribute to the inhibition of adipocyte differentiation in hypoxia through downregulation of C/EBPα expression. Collectively, these results demonstrate that ATF3 represses the C/EBPα gene, resulting in inhibition of adipocyte differentiation, and thus plays a role in hypoxia-mediated inhibition of adipocyte differentiation.

  10. Carbamazepine directly inhibits adipocyte differentiation through activation of the ERK 1/2 pathway

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    Turpin, E; Muscat, A; Vatier, C; Chetrite, G; Corruble, E; Moldes, M; Fève, B

    2013-01-01

    Background and Purpose Carbamazepine (CBZ), known for its anti-epileptic, analgesic and mood-stabilizing properties, is also known to induce weight gain but the pathophysiology of this adverse effect is still largely unknown. We tested the hypothesis that CBZ could have a direct effect on adipocyte development and metabolism. Experimental Research We studied the effects of CBZ on morphological biochemical and molecular markers of adipogenesis, using several pre-adipocyte murine cell lines (3T3-L1, 3T3-F442A and T37i cells) and primary cultures of human pre-adipocytes. To delineate the mechanisms underlying the effect of CBZ, clonal expansion of pre-adipocytes, pro-adipogenic transcription factors, glucose uptake and lipolysis were also examined. Key Results CBZ strongly inhibited pre-adipocyte differentiation and triglyceride accumulation in a time- and dose-dependent manner in all models. Pleiotropic mechanisms were at the basis of the inhibitory effects of CBZ on adipogenesis and cell lipid accumulation. They included suppression of both clonal expansion and major adipogenic transcription factors such as PPAR-γ and CCAAT/enhancer binding protein-α, activation of basal lipolysis and decrease in insulin-stimulated glucose transport. Conclusions and Implications The effect of CBZ on adipogenesis involves activation of the ERK1/2 pathway. Our results show that CBZ acts directly on pre-adipocytes and adipocytes to alter adipose tissue development and metabolism. PMID:22889231

  11. Naringenin Inhibits Adipogenesis and Reduces Insulin Sensitivity and Adiponectin Expression in Adipocytes

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    Allison J. Richard

    2013-01-01

    Full Text Available Adipose tissue development and function are widely studied to examine the relationship between obesity and the metabolic syndrome. It is well documented that the inability of adipose tissue to properly increase its lipid storage capacity during the obese state can lead to metabolic dysfunction. In a blind screen of 425 botanicals, we identified naringenin as an inhibitor of adipocyte differentiation. Naringenin is one of the most abundant citrus flavonoids, and recent studies have demonstrated antihyperlipidemic capabilities. These studies have largely focused on the effects of naringenin on the liver. Our biochemical studies clearly demonstrate that naringenin inhibits adipogenesis and impairs mature fat cell function. Naringenin specifically inhibited adipogenesis in a dose-dependent fashion as judged by examining lipid accumulation and induction of adipocyte marker protein expression. In mature 3T3-L1 adipocytes, naringenin reduced the ability of insulin to induce IRS-1 tyrosine phosphorylation and substantially inhibited insulin-stimulated glucose uptake in a dose-dependent manner and over a time frame of 1.5 to 24 hours. Exposure to naringenin also inhibited adiponectin protein expression in mature murine and human adipocytes. Our studies have revealed that naringenin may have a negative impact on adipocyte-related diseases by limiting differentiation of preadipocytes, by significantly inducing insulin resistance, and by decreasing adiponectin expression in mature fat cells.

  12. Hypoxia inhibits semicarbazide-sensitive amine oxidase activity in adipocytes.

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    Repessé, Xavier; Moldes, Marthe; Muscat, Adeline; Vatier, Camille; Chetrite, Gérard; Gille, Thomas; Planes, Carole; Filip, Anna; Mercier, Nathalie; Duranteau, Jacques; Fève, Bruno

    2015-08-15

    Semicarbazide-sensitive amine oxidase (SSAO), an enzyme highly expressed on adipocyte plasma membranes, converts primary amines into aldehydes, ammonium and hydrogen peroxide, and is likely involved in endothelial damage during the course of diabetes and obesity. We investigated whether in vitro, adipocyte SSAO was modulated under hypoxic conditions that is present in adipose tissue from obese or intensive care unit. Physical or pharmacological hypoxia decreased SSAO activity in murine adipocytes and human adipose tissue explants, while enzyme expression was preserved. This effect was time-, dose-dependent and reversible. This down-regulation was confirmed in vivo in subcutaneous adipose tissue from a rat model of hypoxia. Hypoxia-induced suppression in SSAO activity was independent of the HIF-1-α pathway or of oxidative stress, but was partially antagonized by medium acidification. Hypoxia-induced down-regulation of SSAO activity could represent an adaptive mechanism to lower toxic molecules production, and may thus protect from tissue injury during these harmful conditions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. ATF3 inhibits adipocyte differentiation of 3T3-L1 cells

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    Jang, Min Kyung; Kim, Cho Hee [School of Korean Medicine, Pusan National University, 30 Beom-eo ri, Mulguem-eup, Yangsan-si, Gyeongnam 609-735 (Korea, Republic of); Seong, Je Kyung [Department of Anatomy and Cell Biology, College of Veterinary Medicine, Seoul National University, Seoul 151-742 (Korea, Republic of); Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr [School of Korean Medicine, Pusan National University, 30 Beom-eo ri, Mulguem-eup, Yangsan-si, Gyeongnam 609-735 (Korea, Republic of)

    2012-04-27

    Highlights: Black-Right-Pointing-Pointer Overexpression of ATF3 inhibits adipocyte differentiation in 3T3-L1 cells. Black-Right-Pointing-Pointer Overexpression of ATF3 represses C/EBP{alpha} expression. Black-Right-Pointing-Pointer ATF3 directly binds to mouse C/EBP{alpha} promoter spanning from -1928 to -1907. Black-Right-Pointing-Pointer ATF3 may play a role in hypoxia-mediated inhibition of adipocyte differentiation. -- Abstract: ATF3 is a stress-adaptive gene that regulates proliferation or apoptosis under stress conditions. However, the role of ATF3 is unknown in adipocyte cells. Therefore, in this study, we investigated the functional role of ATF3 in adipocytes. Both lentivirus-mediated overexpression of ATF3 and stably-overexpressed ATF3 inhibited adipocyte differentiation in 3T3-L1 cells, as revealed by decreased lipid staining with oil red staining and reduction in adipogenic genes. Thapsigargin treatment and overexpression of ATF3 decreased C/EBP{alpha} transcript and repressed the activity of the 3.6-kb mouse C/EBP{alpha} promoter, demonstrating that ATF3 downregulates C/EBP{alpha} expression. Transfection studies using mutant constructs containing 5 Prime -deletions in the C/EBP{alpha} promoter revealed that a putative ATF/CRE element, GGATGTCA, is located between -1921 and -1914. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 directly binds to mouse C/EBP{alpha} promoter spanning from -1928 to -1907. Both chemical hypoxia-mimetics or physical hypoxia led to reduce the C/EBP{alpha} mRNA and repress the promoter activity of the C/EBP{alpha} gene, whereas increase ATF3 mRNA, suggesting that ATF3 may contribute to the inhibition of adipocyte differentiation in hypoxia through downregulation of C/EBP{alpha} expression. Collectively, these results demonstrate that ATF3 represses the C/EBP{alpha} gene, resulting in inhibition of adipocyte differentiation, and thus plays a role in hypoxia-mediated inhibition

  14. JAZF1 can regulate the expression of lipid metabolic genes and inhibit lipid accumulation in adipocytes

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    Ming, Guang-feng [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Xiao, Di; Gong, Wei-jing [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Liu, Hui-xia; Liu, Jun [Department of Geriatrics, Xiangya Hospital, Central South University, Changsha 410008, Hunan (China); Zhou, Hong-hao [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China); Liu, Zhao-qian, E-mail: liuzhaoqian63@126.com [Institute of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha 410078, Hunan (China)

    2014-03-14

    Highlights: • JAZF1 was significantly upregulated during the differentiation of 3T3-L1 preadipocytes. • JAZF1 overexpression inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes. • JAZF1 overexpression inhibited the expression of SREBP1, ACC, and FAS. • JAZF1 overexpression upregulated the expression of HSL and ATGL. • SREBP1 and JAZF1 could regulate each other in adipocytes. - Abstract: JAZF1 is a newly identified gene with unknown functions. A recent genome-wide association study showed that JAZF1 is associated with type 2 diabetes and is highly expressed in liver and adipose tissue. Studies have demonstrated that JAZF1 is the co-repressor for nuclear orphan receptor TAK1, whereas most nuclear orphan receptor family members are involved in the regulation of lipid metabolism. Therefore, JAZF1 could be closely related to glycolipid metabolism. In this study, JAZF1 was significantly upregulated during the induced differentiation process of 3T3-L1 preadipocytes. The overexpression of JAZF1 inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes and significantly inhibited the expression of SREBPl, ACC, and FAS, which were important in lipid synthesis, while upregulating the expression of key enzyme hormone-sensitive lipase in lipoclasis. Moreover, SREBPl exhibited an inhibitory function on the expression of JAZF1. SREBP1 reversed the inhibitory action on lipid accumulation of JAZF1. SREBP1 and JAZF1 were observed to regulate each other in adipocytes. Therefore, JAZF1 could regulate the expression of particular genes related to lipid metabolism and inhibit lipid accumulation in adipocytes. This result suggests that JAZF1 may be a potential target for the treatment of diseases, such as obesity and lipid metabolism disorders.

  15. JAZF1 can regulate the expression of lipid metabolic genes and inhibit lipid accumulation in adipocytes

    International Nuclear Information System (INIS)

    Ming, Guang-feng; Xiao, Di; Gong, Wei-jing; Liu, Hui-xia; Liu, Jun; Zhou, Hong-hao; Liu, Zhao-qian

    2014-01-01

    Highlights: • JAZF1 was significantly upregulated during the differentiation of 3T3-L1 preadipocytes. • JAZF1 overexpression inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes. • JAZF1 overexpression inhibited the expression of SREBP1, ACC, and FAS. • JAZF1 overexpression upregulated the expression of HSL and ATGL. • SREBP1 and JAZF1 could regulate each other in adipocytes. - Abstract: JAZF1 is a newly identified gene with unknown functions. A recent genome-wide association study showed that JAZF1 is associated with type 2 diabetes and is highly expressed in liver and adipose tissue. Studies have demonstrated that JAZF1 is the co-repressor for nuclear orphan receptor TAK1, whereas most nuclear orphan receptor family members are involved in the regulation of lipid metabolism. Therefore, JAZF1 could be closely related to glycolipid metabolism. In this study, JAZF1 was significantly upregulated during the induced differentiation process of 3T3-L1 preadipocytes. The overexpression of JAZF1 inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes and significantly inhibited the expression of SREBPl, ACC, and FAS, which were important in lipid synthesis, while upregulating the expression of key enzyme hormone-sensitive lipase in lipoclasis. Moreover, SREBPl exhibited an inhibitory function on the expression of JAZF1. SREBP1 reversed the inhibitory action on lipid accumulation of JAZF1. SREBP1 and JAZF1 were observed to regulate each other in adipocytes. Therefore, JAZF1 could regulate the expression of particular genes related to lipid metabolism and inhibit lipid accumulation in adipocytes. This result suggests that JAZF1 may be a potential target for the treatment of diseases, such as obesity and lipid metabolism disorders

  16. Uridine prevents fenofibrate-induced fatty liver.

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    Thuc T Le

    Full Text Available Uridine, a pyrimidine nucleoside, can modulate liver lipid metabolism although its specific acting targets have not been identified. Using mice with fenofibrate-induced fatty liver as a model system, the effects of uridine on liver lipid metabolism are examined. At a daily dosage of 400 mg/kg, fenofibrate treatment causes reduction of liver NAD(+/NADH ratio, induces hyper-acetylation of peroxisomal bifunctional enzyme (ECHD and acyl-CoA oxidase 1 (ACOX1, and induces excessive accumulation of long chain fatty acids (LCFA and very long chain fatty acids (VLCFA. Uridine co-administration at a daily dosage of 400 mg/kg raises NAD(+/NADH ratio, inhibits fenofibrate-induced hyper-acetylation of ECHD, ACOX1, and reduces accumulation of LCFA and VLCFA. Our data indicates a therapeutic potential for uridine co-administration to prevent fenofibrate-induced fatty liver.

  17. Perilipin 1 Mediates Lipid Metabolism Homeostasis and Inhibits Inflammatory Cytokine Synthesis in Bovine Adipocytes

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    Shiqi Zhang

    2018-03-01

    Full Text Available Dairy cows with ketosis displayed lipid metabolic disorder and high inflammatory levels. Adipose tissue is an active lipid metabolism and endocrine tissue and is closely related to lipid metabolism homeostasis and inflammation. Perilipin 1 (PLIN1, an adipocyte-specific lipid-coated protein, may be involved in the above physiological function. The aim of this study is to investigate the role of PLIN1 in lipid metabolism regulation and inflammatory factor synthesis in cow adipocytes. The results showed that PLIN1 overexpression upregulated the expression of fatty acid and triglyceride (TAG synthesis molecule sterol regulator element-binding protein-1c (SREBP-1c and its target genes, diacylglycerol acyltransferase (DGAT 1, and DGAT2, but inhibited the expression of lipolysis enzymes hormone-sensitive lipase (HSL and CGI-58 for adipose triglyceride lipase (ATGL, thus augmenting the fatty acids and TAG synthesis and inhibiting lipolysis. Importantly, PLIN1 overexpression inhibited the activation of the NF-κB inflammatory pathway and decreased the expression and content of tumor necrosis factor alpha (TNF-α, interleukin 1 beta (IL-1β, and interleukin 6 (IL-6 induced by lipopolysaccharide. Conversely, PLIN1 silencing inhibited TAG synthesis, promoted lipolysis, and overinduced the activation of the NF-κB inflammatory pathway in cow adipocytes. In ketotic cows, the expression of PLIN1 was markedly decreased, whereas lipid mobilization, NF-κB pathway, and downstream inflammatory cytokines were overinduced in adipose tissue. Taken together, these results indicate that PLIN1 can maintain lipid metabolism homeostasis and inhibit the NF-κB inflammatory pathway in adipocytes. However, low levels of PLIN1 reduced the inhibitory effect on fat mobilization, NF-κB pathway, and inflammatory cytokine synthesis in ketotic cows.

  18. HIV protease inhibitors disrupt lipid metabolism by activating endoplasmic reticulum stress and inhibiting autophagy activity in adipocytes.

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    Beth S Zha

    Full Text Available HIV protease inhibitors (PI are core components of Highly Active Antiretroviral Therapy (HAART, the most effective treatment for HIV infection currently available. However, HIV PIs have now been linked to lipodystrophy and dyslipidemia, which are major risk factors for cardiovascular disease and metabolic syndrome. Our previous studies have shown that HIV PIs activate endoplasmic reticulum (ER stress and disrupt lipid metabolism in hepatocytes and macrophages. Yet, little is known on how HIV PIs disrupt lipid metabolism in adipocytes, a major cell type involved in the pathogenesis of metabolic syndrome.Cultured and primary mouse adipocytes and human adipocytes were used to examine the effect of frequently used HIV PIs in the clinic, lopinavir/ritonavir, on adipocyte differentiation and further identify the underlying molecular mechanism of HIV PI-induced dysregulation of lipid metabolism in adipocytes. The results indicated that lopinavir alone or in combination with ritonavir, significantly activated the ER stress response, inhibited cell differentiation, and induced cell apoptosis in adipocytes. In addition, HIV PI-induced ER stress was closely linked to inhibition of autophagy activity. We also identified through the use of primary adipocytes of CHOP(-/- mice that CHOP, the major transcriptional factor of the ER stress signaling pathway, is involved in lopinavir/ritonavir-induced inhibition of cell differentiation in adipocytes. In addition, lopinavir/ritonavir-induced ER stress appears to be associated with inhibition of autophagy activity in adipocytes.Activation of ER stress and impairment of autophagy activity are involved in HIV PI-induced dysregulation of lipid metabolism in adipocytes. The key components of ER stress and autophagy signaling pathways are potential therapeutic targets for HIV PI-induced metabolic side effects in HIV patients.

  19. Rubi Fructus (Rubus coreanus Inhibits Differentiation to Adipocytes in 3T3-L1 Cells

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    Mi-Young Jeong

    2013-01-01

    Full Text Available Rubi Fructus (RF is known to exert several pharmacological effects including antitumor, antioxidant, and anti-inflammatory activities. However, its antiobesity effect has not been reported yet. This study was focused on the antidifferentiation effect of RF extract on 3T3-L1 preadipocytes. When 3T3-L1 preadipocytes were differentiating into adipocytes, 10–100 μg/mL of RF was added. Next, the lipid contents were quantified by Oil Red O staining. RF significantly reduced lipid accumulation and downregulated the expression of peroxisome proliferator-activated receptor γ (PPARγ, CCAAT0-enhancer-binding proteins α (C/EBPα, adipocyte fatty acid-binding protein 2 (aP2, resistin, and adiponectin in ways that were concentration dependent. Moreover, RF markedly upregulated liver kinase B1 and AMP-activated protein kinase (AMPK. Interestingly, pretreatment with AMPKα siRNA and RF downregulated the expression of PPARγ and C/EBPα protein as well as the adipocyte differentiation. Our study shows that RF is capable of inhibiting the differentiation of 3T3-L1 adipocytes through the modulation of PPARγ, C/EBPα, and AMPK, suggesting that it has a potential for therapeutic application in the treatment or prevention of obesity.

  20. JAZF1 can regulate the expression of lipid metabolic genes and inhibit lipid accumulation in adipocytes.

    Science.gov (United States)

    Ming, Guang-feng; Xiao, Di; Gong, Wei-jing; Liu, Hui-xia; Liu, Jun; Zhou, Hong-hao; Liu, Zhao-qian

    2014-03-14

    JAZF1 is a newly identified gene with unknown functions. A recent genome-wide association study showed that JAZF1 is associated with type 2 diabetes and is highly expressed in liver and adipose tissue. Studies have demonstrated that JAZF1 is the co-repressor for nuclear orphan receptor TAK1, whereas most nuclear orphan receptor family members are involved in the regulation of lipid metabolism. Therefore, JAZF1 could be closely related to glycolipid metabolism. In this study, JAZF1 was significantly upregulated during the induced differentiation process of 3T3-L1 preadipocytes. The overexpression of JAZF1 inhibited lipid accumulation in differentiated mature 3T3-L1 adipocytes and significantly inhibited the expression of SREBPl, ACC, and FAS, which were important in lipid synthesis, while upregulating the expression of key enzyme hormone-sensitive lipase in lipoclasis. Moreover, SREBPl exhibited an inhibitory function on the expression of JAZF1. SREBP1 reversed the inhibitory action on lipid accumulation of JAZF1. SREBP1 and JAZF1 were observed to regulate each other in adipocytes. Therefore, JAZF1 could regulate the expression of particular genes related to lipid metabolism and inhibit lipid accumulation in adipocytes. This result suggests that JAZF1 may be a potential target for the treatment of diseases, such as obesity and lipid metabolism disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Go-6976 reverses hyperglycemia-induced insulin resistance independently of cPKC inhibition in adipocytes.

    Directory of Open Access Journals (Sweden)

    Katherine A Robinson

    Full Text Available Chronic hyperglycemia induces insulin resistance by mechanisms that are incompletely understood. One model of hyperglycemia-induced insulin resistance involves chronic preincubation of adipocytes in the presence of high glucose and low insulin concentrations. We have previously shown that the mTOR complex 1 (mTORC1 plays a partial role in the development of insulin resistance in this model. Here, we demonstrate that treatment with Go-6976, a widely used "specific" inhibitor of cPKCs, alleviates hyperglycemia-induced insulin resistance. However, the effects of mTOR inhibitor, rapamycin and Go-6976 were not additive and only rapamycin restored impaired insulin-stimulated AKT activation. Although, PKCα, (but not -β was abundantly expressed in these adipocytes, our studies indicate cPKCs do not play a major role in causing insulin-resistance in this model. There was no evidence of changes in the expression or phosphorylation of PKCα, and PKCα knock-down did not prevent the reduction of insulin-stimulated glucose transport. This was also consistent with lack of IRS-1 phosphorylation on Ser-24 in hyperglycemia-induced insulin-resistant adipocytes. Treatment with Go-6976 did inhibit a component of the mTORC1 pathway, as evidenced by decreased phosphorylation of S6 ribosomal protein. Raptor knock-down enhanced the effect of insulin on glucose transport in insulin resistant adipocytes. Go-6976 had the same effect in control cells, but was ineffective in cells with Raptor knock-down. Taken together these findings suggest that Go-6976 exerts its effect in alleviating hyperglycemia-induced insulin-resistance independently of cPKC inhibition and may target components of the mTORC1 signaling pathway.

  2. Go-6976 Reverses Hyperglycemia-Induced Insulin Resistance Independently of cPKC Inhibition in Adipocytes

    Science.gov (United States)

    Robinson, Katherine A.; Hegyi, Krisztina; Hannun, Yusuf A.; Buse, Maria G.; Sethi, Jaswinder K.

    2014-01-01

    Chronic hyperglycemia induces insulin resistance by mechanisms that are incompletely understood. One model of hyperglycemia-induced insulin resistance involves chronic preincubation of adipocytes in the presence of high glucose and low insulin concentrations. We have previously shown that the mTOR complex 1 (mTORC1) plays a partial role in the development of insulin resistance in this model. Here, we demonstrate that treatment with Go-6976, a widely used “specific” inhibitor of cPKCs, alleviates hyperglycemia-induced insulin resistance. However, the effects of mTOR inhibitor, rapamycin and Go-6976 were not additive and only rapamycin restored impaired insulin-stimulated AKT activation. Although, PKCα, (but not –β) was abundantly expressed in these adipocytes, our studies indicate cPKCs do not play a major role in causing insulin-resistance in this model. There was no evidence of changes in the expression or phosphorylation of PKCα, and PKCα knock-down did not prevent the reduction of insulin-stimulated glucose transport. This was also consistent with lack of IRS-1 phosphorylation on Ser-24 in hyperglycemia-induced insulin-resistant adipocytes. Treatment with Go-6976 did inhibit a component of the mTORC1 pathway, as evidenced by decreased phosphorylation of S6 ribosomal protein. Raptor knock-down enhanced the effect of insulin on glucose transport in insulin resistant adipocytes. Go-6976 had the same effect in control cells, but was ineffective in cells with Raptor knock-down. Taken together these findings suggest that Go-6976 exerts its effect in alleviating hyperglycemia-induced insulin-resistance independently of cPKC inhibition and may target components of the mTORC1 signaling pathway. PMID:25330241

  3. Lactacystin inhibits 3T3-L1 adipocyte differentiation through induction of CHOP-10 expression

    International Nuclear Information System (INIS)

    Li Xi; Huang Haiyan; Chen Jiegen; Jiang Lin; Liu Honglei; Liu Deguo; Song Tanjing; He Qun; Ma Chungu; Ma Duan; Song Houyan; Tang Qiqun

    2006-01-01

    Hormonal induction triggers a cascade leading to the expression of CCAAT/enhancer-binding protein(C/EBP)α and peroxisome proliferator-activated receptor (PPAR) γ, C/EBPα, and PPARγ turns on series of adipocyte genes that give rise to the adipocyte phenotype. Previous findings indicate that C/EBPβ, a transcriptional activator of the C/EBPα and PPARγ genes, is rapidly expressed after induction, but lacks DNA-binding activity and therefore cannot activate transcription of the C/EBPα and PPARγ genes early in the differentiation program. Acquisition of DNA-binding activity of C/EBPβ occurs when CHOP-10, a dominant-negative form of C/EBP family members, is down-regulated and becomes hyperphosphorylated as preadipocytes traverse the G 1 -S checkpoint of mitotic clonal expansion. Evidences are presented in this report that lactacystin, a proteasome inhibitor, up-regulated the CHOP-10 expression, blocked the DNA-binding activity of C/EBPβ, and subsequently inhibited MCE as well as adipocyte differentiation

  4. WISP1/CCN4 inhibits adipocyte differentiation through repression of PPARγ activity.

    Science.gov (United States)

    Ferrand, Nathalie; Béreziat, Véronique; Moldes, Marthe; Zaoui, Maurice; Larsen, Annette K; Sabbah, Michèle

    2017-05-11

    WISP1 (Wnt1-inducible signaling pathway protein-1, also known as CCN4) is a member of the CCN family able to mediate cell growth, transformation and survival in a tissue-specific manner. Here, we report that WISP1 expression was highly increased in preadipocytes and decreased during adipocyte differentiation. Moreover, we observed an increase in WISP1 gene expression in adipose tissue from both diet-induced and leptin-deficient ob/ob obese mice, suggesting that WISP1 could be involved in the pathophysiological onset of obesity. Interestingly, overexpression of WISP1 in 3T3-F442A cells prevented adipocyte differentiation via downregulation of peroxisome proliferator-activated receptor (PPARγ) transcriptional activity thereby attenuating the expression of adipogenic markers. Conversely, silencing of WISP1 enhanced adipocyte differentiation. We further show that the inactivation of PPARγ transcriptional activity was mediated, at least in part, by a direct physical association between WISP1 and PPARγ, followed by proteasome-dependent degradation of PPARγ. These results suggest for the first time that WISP1 interacts with PPARγ and that this interaction results in the inhibition of PPARγ activity. Taken together our results suggest that WISP1 functions as a negative regulator of adipogenesis.

  5. Chilean native fruit extracts inhibit inflammation linked to the pathogenic interaction between adipocytes and macrophages.

    Science.gov (United States)

    Reyes-Farias, Marjorie; Vasquez, Karla; Ovalle-Marin, Angelica; Fuentes, Francisco; Parra, Claudia; Quitral, Vilma; Jimenez, Paula; Garcia-Diaz, Diego F

    2015-05-01

    Obesity is characterized by an increase in the infiltration of monocytes into the adipose tissue, causing an inflammatory condition associated with, for example, the development of insulin resistance. Thus, anti-inflammatory-based treatments could emerge as a novel and interesting approach. It has been reported that Chilean native fruits maqui (Aristotelia chilensis) and calafate (Berberis microphylla) present high contents of polyphenols, which are known for their antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the ability of extracts of these fruits to block the pathogenic interaction between adipocytes and macrophages in vitro and to compare its effect with blueberry (Vaccinium corymbosum) extract treatment, which has been already described to possess several biomedical benefits. RAW264.7 macrophages were treated with 5 μg/mL lipopolysaccharides (LPS), with conditioned media (CM) from fully differentiated 3T3-L1 adipocytes, or in a coculture (CC) with 3T3-L1 adipocytes, in the presence or absence of 100 μM [total polyphenolic content] of each extract for 24 h. The gene expression and secretion profile of several inflammatory markers were evaluated. Nitric oxide secretion induced by LPS, CM, and CC was reduced by the presence of maqui (-12.2%, -45.6%, and -14.7%, respectively) and calafate (-27.6%, -43.9%, and -11.8%, respectively) extracts. Gene expression of inducible nitric oxide synthase and TNF-α was inhibited and of IL-10 was induced by maqui and calafate extract incubation. In conclusion, the extracts of these fruits present important inhibitory-like features over the inflammatory response of the interaction between adipocytes and macrophages, comprising a potential therapeutic tool against comorbidities associated with obesity development.

  6. WEHI-3 cells inhibit adipocyte differentiation in 3T3-L1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jing [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Liu, Gexiu [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Yan, Guoyao [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); He, Dongmei [Institute of Hematology, School of Medicine, Jinan University, Guangzhou, Guangdong (China); Zhou, Ying [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China); Chen, Shengting, E-mail: shengtingchen@sina.cn [The First Affiliated Hospital, Jinan University, Guangzhou, Guangdong (China)

    2015-06-26

    By investigating the anti-adipogenic effects of WEHI-3 cells – a murine acute myelomonocytic leukemia cell line – we sought to improve the efficiency of hematopoietic stem cell transplantation (HSCT). Analysis of Oil Red O staining and the expression of adipogenic genes, including PPARγ, C/EBPα, FAS and LPL, indicated that WEHI-3 cells significantly inhibited 3T3-L1 mouse preadipocyte cells from differentiating into adipocytes. In vivo, fat vacuoles in mice injected with WEHI-3 cells were also remarkably reduced in the murine bone marrow pimelosis model. Moreover, the key gene in the Rho signaling pathway, ROCKII, and the key gene in the Wnt signaling pathway, β-catenin, were both upregulated compared with the control group. siRNA-mediated knockdown of ROCKII and β-catenin reversed these WEHI-3-mediated anti-adipogenic effects. Taken together, these data suggest that WEHI-3 cells exert anti-adipogenic effects and that both ROCKII and β-catenin are involved in this process. - Highlights: • WEHI-3, an acute myelomonocytic leukemia cell line, inhibited 3T3-L1 preadipocyte from differentiating into adipocyte. • WEHI-3 cells can arrest 3T3-L1 cells in G0/G1 phase by secreting soluble factors and thus inhibit their proliferation. • WEHI-3 cells reduced bone marrow pimelosis in the murine model. • Both ROCKII and β-catenin were involved in the WEHI-3-mediated anti-adipogenic effects.

  7. Thiazolopyridines Improve Adipocyte Function by Inhibiting 11 Beta-HSD1 Oxoreductase Activity

    Directory of Open Access Journals (Sweden)

    Thirumurugan Rathinasabapathy

    2017-01-01

    Full Text Available Background. Glucocorticoid excess has been linked to clinical observations associated with the pathophysiology of metabolic syndrome. The intracellular glucocorticoid levels are primarily modulated by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1 enzyme that is highly expressed in key metabolic tissues including fat, liver, and the central nervous system. Methods. In this study we synthesized a set of novel tetrahydrothiazolopyridine derivatives, TR-01–4, that specifically target 11β-HSD1 and studied their ability to interfere with the glucocorticoid and lipid metabolism in the 3T3-L1 adipocytes. Results. Based on the docking model and structure-activity relationships, tetrahydrothiazolopyridine derivatives TR-02 and TR-04 showed the highest potency against 11β-HSD1 by dose-dependently inhibiting conversion of cortisone to cortisol (IC50 values of 1.8 μM and 0.095 μM, resp.. Incubation of fat cells with 0.1–10 μM TR-01–4 significantly decreased cortisone-induced lipid accumulation in adipocytes and suppressed 11β-HSD1 mRNA expression. Observed reduction in adipocyte fat stores could be partially explained by decreased expression levels of adipogenic markers (PPAR-γ, aP2 and key enzymes of lipid metabolism, including fatty acid synthase (FAS, hormone sensitive lipase (HSL, and lipoprotein lipase (LPL. Conclusions. The tetrahydrothiazolopyridine moiety served as an active pharmacophore for inhibiting 11β-HSD1 and offered a novel therapeutic strategy to ameliorate metabolic alterations found in obesity and diabetes.

  8. Vitamin C inhibits leptin secretion and some glucose/lipid metabolic pathways in primary rat adipocytes.

    Science.gov (United States)

    Garcia-Diaz, D F; Campion, J; Milagro, F I; Boque, N; Moreno-Aliaga, M J; Martinez, J A

    2010-07-01

    Antioxidant-based treatments are emerging as an interesting approach to possibly counteract obesity fat accumulation complications, since this is accompanied by an increased systemic oxidative stress. The aim of this study was to analyze specific metabolic effects of vitamin C (VC) on epididymal primary rat adipocytes. Cells were isolated and incubated for 72 h in culture medium, in the absence or presence of 1.6 nM insulin, within a range of VC concentrations (5-1000 microM). Glucose- and lipid-related variables as well as the secretion/expression patterns of several obesity-related genes were assessed. It was observed that VC dose dependently inhibited glucose uptake and lactate production, and also reduced glycerol release in both control and insulin-treated cells. Also, VC caused a dramatic concentration-dependent fall in leptin secretion especially in insulin-stimulated cells. In addition, VC (200 microM) induced Cdkn1a and Casp8, partially inhibited Irs3, and together with insulin drastically reduced Gpdh (listed as Gpd1 in the MGI database) gene expressions. Finally, VC and insulin down-regulatory effects were observed on extracellular and intracellular reactive oxygen species production respectively. In summary, this experimental assay describes a specific effect of VC in isolated rat adipocytes on glucose and fat metabolism, and on the secretion/expression of important obesity-related proteins.

  9. Hibiscus sabdariffa L. water extract inhibits the adipocyte differentiation through the PI3-K and MAPK pathway.

    Science.gov (United States)

    Kim, Jin-Kyung; So, Hongseob; Youn, Myung-Ja; Kim, Hyung-Jin; Kim, Yunha; Park, Channy; Kim, Se-Jin; Ha, Young-Ae; Chai, Kyu-Yun; Kim, Shin-Moo; Kim, Ki-Young; Park, Raekil

    2007-11-01

    Hibiscus sabdariffa L., a tropical beverage material and medical herb, is used commonly as in folk medicines against hypertension, pyrexia, inflammation, liver disorders, and obesity. This report was designed to investigate the inhibitory mechanisms of hibiscus extract on adipocyte differentiation in 3T3-L1 preadipocytes. The possible inhibitory pathways that regulate the adipocyte differentiation contain the adipogenic transcription factors, C/EBPalpha and PPARgamma, PI3-kinase, and MAPK pathway. In this study, we examined whether hibiscus extract affected the adipogenesis via these three pathways. To differentiate preadipocyte in adipocyte, confluent 3T3-L1 preadipocytes were treated with the hormone mixture including isobutylmethylxanthine, dexamethasone, and insulin (MDI). Hibiscus extract inhibited significantly the lipid droplet accumulation by MDI in a dose-dependent manner and attenuated dramatically the protein and mRNA expressions of adipogenic transcriptional factors, C/EBPalpha and PPARgamma, during adipogenesis. The increase of phosphorylation and expression of PI3-K/Akt during adipocytic differentiation was markedly inhibited by treatment with hibiscus extract or PI3-K inhibitors. Furthermore, the phosphorylation and expression of MEK-1/ERK known to regulate the early phase of adipogenesis were clearly decreased with the addition of hibiscus extract. Taken together, this report suggests that hibiscus extract inhibits the adipocyte differentiation through the modulation of PI3-K/Akt and ERK pathway that play pivotal roles during adipogenesis.

  10. Inhibition of adipogenesis and leptin production in 3T3-L1 adipocytes by a derivative of meridianin C

    International Nuclear Information System (INIS)

    Park, Yu-Kyoung; Lee, Tae-Yoon; Choi, Jong-Soon; Hong, Victor Sukbong; Lee, Jinho; Park, Jong-Wook; Jang, Byeong-Churl

    2014-01-01

    Highlights: • Compound 7b, a meridianin C derivative, inhibits adipogenesis. • Compound 7b inhibits C/EBP-α, PPAR-γ, FAS, STAT-3, and STAT-5 in 3T3-L1 adipocytes. • Compound 7b inhibits leptin, but not adiponectin, expression in 3T3-L1 adipocytes. • Compound 7b thus may have therapeutic potential against obesity. - Abstract: Meridianin C, a marine alkaloid, is a potent protein kinase inhibitor and has anti-cancer activity. We have recently developed a series of meridianin C derivatives (compound 7a–7j) and reported their proviral integration Moloney Murine Leukemia Virus (pim) kinases’ inhibitory and anti-proliferative effects on human leukemia cells. Here we investigated the effect of these meridianin C derivatives on adipogenesis. Strikingly, among the derivatives tested, compound 7b most strongly inhibited lipid accumulation during the differentiation of 3T3-L1 preadipocytes into adipocytes. However, meridianin C treatment was largely cytotoxic to 3T3-L1 adipocytes. On mechanistic levels, compound 7b reduced not only the expressions of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), and fatty acid synthase (FAS) but also the phosphorylation levels of signal transducer and activator of transcription-3 (STAT-3) and STAT-5 during adipocyte differentiation. Moreover, compound 7b repressed leptin, but not adiponectin, expression during adipocyte differentiation. Collectively, these findings demonstrate that a meridianin C derivative inhibits adipogenesis by down-regulating expressions and/or phosphorylations of C/EBP-α, PPAR-γ, FAS, STAT-3 and STAT-5

  11. Inhibition of adipogenesis and leptin production in 3T3-L1 adipocytes by a derivative of meridianin C

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yu-Kyoung [Department of Molecular Medicine, College of Medicine, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Lee, Tae-Yoon [Department of Microbiology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-gu, Daegu 705-717 (Korea, Republic of); Choi, Jong-Soon [Division of Life Science, Korea Basic Science Institute, 169-148 Gwahakro, Yuseong-gu, Daejeon 305-333 (Korea, Republic of); Hong, Victor Sukbong [Department of Chemistry, College of Natural Sciences, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Lee, Jinho, E-mail: jinho@gw.kmu.ac.kr [Department of Chemistry, College of Natural Sciences, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Park, Jong-Wook, E-mail: j303nih@dsmc.or.kr [Department of Immunology, College of Medicine, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701 (Korea, Republic of); Jang, Byeong-Churl, E-mail: jangbc123@gw.kmu.ac.kr [Department of Molecular Medicine, College of Medicine, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 704-701 (Korea, Republic of)

    2014-10-03

    Highlights: • Compound 7b, a meridianin C derivative, inhibits adipogenesis. • Compound 7b inhibits C/EBP-α, PPAR-γ, FAS, STAT-3, and STAT-5 in 3T3-L1 adipocytes. • Compound 7b inhibits leptin, but not adiponectin, expression in 3T3-L1 adipocytes. • Compound 7b thus may have therapeutic potential against obesity. - Abstract: Meridianin C, a marine alkaloid, is a potent protein kinase inhibitor and has anti-cancer activity. We have recently developed a series of meridianin C derivatives (compound 7a–7j) and reported their proviral integration Moloney Murine Leukemia Virus (pim) kinases’ inhibitory and anti-proliferative effects on human leukemia cells. Here we investigated the effect of these meridianin C derivatives on adipogenesis. Strikingly, among the derivatives tested, compound 7b most strongly inhibited lipid accumulation during the differentiation of 3T3-L1 preadipocytes into adipocytes. However, meridianin C treatment was largely cytotoxic to 3T3-L1 adipocytes. On mechanistic levels, compound 7b reduced not only the expressions of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), and fatty acid synthase (FAS) but also the phosphorylation levels of signal transducer and activator of transcription-3 (STAT-3) and STAT-5 during adipocyte differentiation. Moreover, compound 7b repressed leptin, but not adiponectin, expression during adipocyte differentiation. Collectively, these findings demonstrate that a meridianin C derivative inhibits adipogenesis by down-regulating expressions and/or phosphorylations of C/EBP-α, PPAR-γ, FAS, STAT-3 and STAT-5.

  12. CUDC-907 Promotes Bone Marrow Adipocytic Differentiation Through Inhibition of Histone Deacetylase and Regulation of Cell Cycle

    DEFF Research Database (Denmark)

    Ali, Dalia; Alshammari, Hassan; Vishnubalaji, Radhakrishnan

    2017-01-01

    with quantitative polymerase chain reaction showed significant increase in H3K9ac epigenetic marker in the promoter regions of AdipoQ, FABP4, PPARγ, KLF15, and CEBPA in CUDC-907-treated hBMSCs. Follow-up experiments corroborated that the inhibition of histone deacetylase (HDAC) activity enhanced adipocytic...

  13. Seapolynol Extracted from Ecklonia cava Inhibits Adipocyte Differentiation in Vitro and Decreases Fat Accumulation in Vivo

    Directory of Open Access Journals (Sweden)

    Hui-Jeon Jeon

    2015-12-01

    Full Text Available Seapolynol (SN is a polyphenol mixture derived from Ecklonia cava. We evaluated the effects of SN on lipid accumulation in adipocytes, zebrafish, and mice. SN effectively inhibited lipid accumulation in three experimental models by suppressing adipogenic factors. Triglyceride synthetic enzymes such as diacylglycerol acyltransferase 1 (DGAT1 and GPAT3 were also downregulated by SN. This SN-induced inhibition of adipogenic factors was shown to be due to the regulatory effect of SN on early adipogenic factors; SN downregulated the expression of Krueppel-like factor 4 (KLF4, KLF5, CCAAT-enhancer-binding protein β (C/EBPβ, C/EBPδ, and Protein C-ets-2 (ETS2, while KLF2, an anti-early adipogenic factor, was upregulated by SN. SN-mediated inhibition in early adipogenesis was closely correlated with the inhibition of mitotic clonal expansion via cell cycle arrest. SN inhibited cell cycle progression by suppressing cell cycle regulators, such as cyclin A, cyclinD, and pRb but increased p27, a cell cycle inhibitor. In a mouse study, SN effectively reduced body weight and plasma lipid increases induced by a high-fat diet; triglycerides, total cholesterol, and low-density lipoprotein (LDL levels were markedly reduced by SN. Moreover, SN remarkably improved high-fat-diet-induced hepatic lipid accumulation. Furthermore, SN activated AMP-activated protein kinase-α (AMPKα, an energy sensor, to suppress acetyl-coA carboxylase (ACC, inhibiting lipid synthesis. Our study suggests that SN may be an edible agent that can play a positive role in prevention of metabolic disorders.

  14. Lysosomotropic cationic amphiphilic drugs inhibit adipocyte differentiation in 3T3-L1K cells via accumulation in cells and phospholipid membranes, and inhibition of autophagy.

    Science.gov (United States)

    Kagebeck, Patrik; Nikiforova, Violetta; Brunken, Lars; Easwaranathan, Arrabi; Ruegg, Joelle; Cotgreave, Ian; Munic Kos, Vesna

    2018-04-05

    Some cationic amphiphilic drugs (CADs) have been individually reported to interfere with the differentiation of immune system cells, such as macrophages and dendritic cells. To investigate the possible generic nature of this process, in this study we aimed to see whether these drugs are capable of interfering with the differentiation of adipocytes. Further, we investigated whether this feature might be connected to the lysosomotropic character of these drugs, and their disturbance of intracellular membrane trafficking rather than to the individual pharmacologic properties of each drug. Thus, for the selected set of compounds consisting of seven structurally and pharmacologically diverse CADs and three non-CAD controls we have measured the impact on differentiation of 3T3-L1K murine preadipocytes to adipocytes. We conclude that CADs indeed inhibit adipocyte differentiation, as shown morphologically, at the level of lipid droplet formation and on the expression of genetic markers of adipocytes. Furthermore, the intensity of this inhibitory effect was found to strongly positively correlate with the extent of drug accumulation in adipocytes, with their affinity for phospholipid membranes, as well as with their ability to induce phospholipidosis and inhibit autophagy. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Inhibition of cytokine secretion from adipocytes by 1,25-dihydroxyvitamin D₃ via the NF-κB pathway.

    Science.gov (United States)

    Mutt, Shivaprakash J; Karhu, Toni; Lehtonen, Siri; Lehenkari, Petri; Carlberg, Carsten; Saarnio, Juha; Sebert, Sylvain; Hyppönen, Elina; Järvelin, Marjo-Ritta; Herzig, Karl-Heinz

    2012-11-01

    Adipose tissue inflammation is an important pathological process in obese people, associated with diabetes and cardiovascular disease. We hypothesized that 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] inhibits cytokine secretion from adipocytes via direct inhibition of transcription factor nuclear factor-κB (NF-κB). We utilized two different human models. Bone marrow-derived human mesenchymal stromal cells (hMSCs) differentiated into adipocytes, and adipocytes isolated from biopsies stimulated with lipopolysaccharide (LPS) were treated with or without 1,25(OH)(2)D(3). Expression and secretion of interleukin-6 (IL-6) were measured by quantitative RT-PCR analysis and ELISA. Assessment of NF-κB nuclear translocation, DNA binding activity was performed by immunofluorescence (IF) and electrophoretic mobility assay (EMSA). Inhibitor κB (IκB) and its phosphorylation were detected by Western blot (WB) analysis. Simultaneous 1,25(OH)(2)D(3) cotreatment significantly reduced LPS-stimulated (10 ng/ml) IL-6 secretion dose dependently by 15% at 10(-10) M and 26% at 10(-7) M (P<0.05) in hMSCs, while preincubation with 1,25(OH)(2)D(3) (10(-7) M) for 24 h reduced IL-6 secretion by 24 and 35% (P<0.001) and mRNA levels by 34 and 30% (P<0.05) in hMSCs and isolated adipocytes, respectively. 1,25(OH)(2)D(3) suppressed LPS-stimulated IκB phosphorylation-mediated NF-κB translocation into the nucleus were evident from WB, IF, and EMSA. 1,25(OH)(2)D(3) inhibits LPS-stimulated IL-6 secretion in two human adipocyte models via interference with NF-κB signaling.

  16. Parabens inhibit fatty acid amide hydrolase: A potential role in paraben-enhanced 3T3-L1 adipocyte differentiation

    OpenAIRE

    Kodani, Sean D.; Overby, Haley B.; Morisseau, Christophe; Chen, Jiangang; Zhao, Ling; Hammock, Bruce D.

    2016-01-01

    Parabens are a class of small molecules that are regularly used as preservatives in a variety of personal care products. Several parabens, including butylparaben and benzylparaben, have been found to interfere with endocrine signaling and to stimulate adipocyte differentiation. We hypothesized these biological effects could be due to interference with the endocannabinoid system and identified fatty acid amide hydrolase (FAAH) as the direct molecular target of parabens. FAAH inhibition by para...

  17. Fenofibrate down-regulates the expressions of androgen receptor (AR) and AR target genes and induces oxidative stress in the prostate cancer cell line LNCaP

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hu; Zhu, Chen; Qin, Chao [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Tao, Tao [Department of Neurosurgery, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Li, Jie; Cheng, Gong; Li, Pu; Cao, Qiang; Meng, Xiaoxin; Ju, Xiaobing; Shao, Pengfei; Hua, Lixin [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Gu, Min, E-mail: medzhao1980@163.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Yin, Changjun, E-mail: drcjyin@gmail.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China)

    2013-03-08

    Highlights: ► Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells. ► Fenofibrate reduces the expressions of androgen receptor in LNCaP cells. ► Fenofibrate induces oxidative stress in the prostate cancer cell line LNCaP. -- Abstract: Fenofibrate, a peroxisome proliferator-androgen receptor-alpha agonist, is widely used in treating different forms of hyperlipidemia and hypercholesterolemia. Recent reports have indicated that fenofibrate exerts anti-proliferative and pro-apoptotic properties. This study aims to investigate the effects of fenofibrate on the prostate cancer (PCa) cell line LNCaP. The effects of fenofibrate on LNCaP cells were evaluated by flow cytometry, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assays, Western blot analysis, and dual-luciferase reporter assay. Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells, reduces the expressions of androgen receptor (AR) and AR target genes (prostate-specific antigen and TMPRSS2), and inhibits Akt phosphorylation. Fenofibrate can induce the accumulation of intracellular reactive oxygen species and malondialdehyde, and decrease the activities of total anti-oxidant and superoxide dismutase in LNCaP cells. Fenofibrate exerts an anti-proliferative property by inhibiting the expression of AR and induces apoptosis by causing oxidative stress. Therefore, our data suggest fenofibrate may have beneficial effects in fenofibrate users by preventing prostate cancer growth through inhibition of androgen activation and expression.

  18. Momordica charantia (bitter melon inhibits primary human adipocyte differentiation by modulating adipogenic genes

    Directory of Open Access Journals (Sweden)

    Nerurkar Vivek R

    2010-06-01

    Full Text Available Abstract Background Escalating trends of obesity and associated type 2 diabetes (T2D has prompted an increase in the use of alternative and complementary functional foods. Momordica charantia or bitter melon (BM that is traditionally used to treat diabetes and complications has been demonstrated to alleviate hyperglycemia as well as reduce adiposity in rodents. However, its effects on human adipocytes remain unknown. The objective of our study was to investigate the effects of BM juice (BMJ on lipid accumulation and adipocyte differentiation transcription factors in primary human differentiating preadipocytes and adipocytes. Methods Commercially available cryopreserved primary human preadipocytes were treated with and without BMJ during and after differentiation. Cytotoxicity, lipid accumulation, and adipogenic genes mRNA expression was measured by commercial enzymatic assay kits and semi-quantitative RT-PCR (RT-PCR. Results Preadipocytes treated with varying concentrations of BMJ during differentiation demonstrated significant reduction in lipid content with a concomitant reduction in mRNA expression of adipocyte transcription factors such as, peroxisome proliferator-associated receptor γ (PPARγ and sterol regulatory element-binding protein 1c (SREBP-1c and adipocytokine, resistin. Similarly, adipocytes treated with BMJ for 48 h demonstrated reduced lipid content, perilipin mRNA expression, and increased lipolysis as measured by the release of glycerol. Conclusion Our data suggests that BMJ is a potent inhibitor of lipogenesis and stimulator of lipolysis activity in human adipocytes. BMJ may therefore prove to be an effective complementary or alternative therapy to reduce adipogenesis in humans.

  19. Parabens inhibit fatty acid amide hydrolase: A potential role in paraben-enhanced 3T3-L1 adipocyte differentiation.

    Science.gov (United States)

    Kodani, Sean D; Overby, Haley B; Morisseau, Christophe; Chen, Jiangang; Zhao, Ling; Hammock, Bruce D

    2016-11-16

    Parabens are a class of small molecules that are regularly used as preservatives in a variety of personal care products. Several parabens, including butylparaben and benzylparaben, have been found to interfere with endocrine signaling and to stimulate adipocyte differentiation. We hypothesized these biological effects could be due to interference with the endocannabinoid system and identified fatty acid amide hydrolase (FAAH) as the direct molecular target of parabens. FAAH inhibition by parabens yields mixed-type and time-independent kinetics. Additionally, structure activity relationships indicate FAAH inhibition is selective for the paraben class of compounds and the more hydrophobic parabens have higher potency. Parabens enhanced 3T3-L1 adipocyte differentiation in a dose dependent fashion, different from two other FAAH inhibitors URB597 and PF622. Moreover, parabens, URB597 and PF622 all failed to enhance AEA-induced differentiation. Furthermore, rimonabant, a cannabinoid receptor 1 (CB 1 )-selective antagonist, did not attenuate paraben-induced adipocyte differentiation. Thus, adipogenesis mediated by parabens likely occurs through modulation of endocannabinoids, but cell differentiation is independent of direct activation of CB 1 by endocannabinoids. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Lactobacillus plantarum LG42 Isolated from Gajami Sik-Hae Inhibits Adipogenesis in 3T3-L1 Adipocyte

    Directory of Open Access Journals (Sweden)

    Jeong-Eun Park

    2013-01-01

    Full Text Available We investigated whether lactic acid bacteria isolated from gajami sik-hae (GLAB are capable of reducing the intracellular lipid accumulation by downregulating the expression of adipogenesis-related genes in differentiated 3T3-L1 cells. The GLAB, Lactobacillus plantarum LG42, significantly decreased the intracellular triglyceride storage and the glycerol-3-phosphate dehydrogenase (GPDH activity in a dose-dependent manner. mRNA expression of transcription factors like peroxisome proliferator-activated receptor (PPAR γ and CCAAT/enhancer-binding protein (C/EBP α involved in adipogenesis was markedly decreased by the GLAB treatment. Moreover, the GLAB also decreased the expression level of adipogenic markers like adipocyte fatty acid binding protein (aP2, leptin, GPDH, and fatty acid translocase (CD36 significantly. These results suggest that the GLAB inhibits lipid accumulation in the differentiated adipocyte through downregulating the expression of adipogenic transcription factors and other specific genes involved in lipid metabolism.

  1. beta-adrenoceptors mediate inhibition of lipolysis in adipocytes of tilapia (Oreochromis mossambicus)

    NARCIS (Netherlands)

    Vianen, GJ; Obels, PP; Van Den Thillart, GEEJM; Zaagsma, J

    The regulation of triglyceride mobilization by catecholamines was investigated in the teleost fish Oreochromis mossambicus (tilapia) in vivo and in vitro. In vitro experiments were carried out with adipocytes that were isolated for the first time from fish adipose tissue. For the in vivo

  2. The retinoblastoma-histone deacetylase 3 complex inhibits PPARgamma and adipocyte differentiation

    DEFF Research Database (Denmark)

    Fajas, Lluis; Egler, Viviane; Reiter, Raphael

    2002-01-01

    (PPARgamma), a nuclear receptor pivotal for adipogenesis, promotes adipocyte differentiation more efficiently in the absence of RB. PPARgamma and RB were shown to coimmunoprecipitate, and this PPARgamma-RB complex also contains the histone deacetylase HDAC3, thereby attenuating PPARgamma's capacity to drive...

  3. Fenofibrate suppressed proliferation and migration of human neuroblastoma cells via oxidative stress dependent of TXNIP upregulation

    Energy Technology Data Exchange (ETDEWEB)

    Su, Cunjin; Shi, Aiming; Cao, Guowen [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Tao, Tao [Department of Urology, Zhongda Hospital, Medical School of Southeast University, Nanjing, 210009 (China); Chen, Ruidong [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Zhanhong; Shen, Zhu; Tao, Hong; Cao, Bin [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Hu, Duanmin, E-mail: hudmsdfey@sina.com [Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China); Bao, Junjie, E-mail: baojjsdfey@sina.com [Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004 (China)

    2015-05-15

    There are no appropriate drugs for metastatic neuroblastoma (NB), which is the most common extra-cranial solid tumor for childhood. Thioredoxin binding protein (TXNIP), the endogenous inhibitor of ROS elimination, has been identified as a tumor suppressor in various solid tumors. It reported that fenofibrate exerts anti-tumor effects in several human cancer cell lines. However, its detail mechanisms remain unclear. The present study assessed the effects of fenofibrate on NB cells and investigated TXNIP role in its anti-tumor mechanisms. We used MTT assay to detect cells proliferation, starch wound test to investigate cells migration, H{sub 2}DCF-DA to detect intracellular ROS, siRNA to interfere TXNIP and peroxisome proliferator-androgen receptor-alpha (PPAR-α) expression, western blot to determine protein levels, flow cytometry to analyze apoptosis. Fenofibrate suppressed proliferation and migration of NB cells, remarkably increased intracellular ROS, upregulated TXNIP expression, promoted cell apoptosis. Furthermore, inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. Our results indicated the anti-tumor role of fenofibrate on NB cells by exacerbating oxidative stress and inducing apoptosis was dependent on the upregulation of TXNIP. - Highlights: • We found that fenofibrate suppressed proliferation and migration of NB cells. • We found that fenofibrate remarkably increased intracellular ROS, upregulated TXNIP expression, and promoted cell apoptosis. • Inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. • Our results indicated the anti-tumor role of fenofibrate on NB cells was dependent on the upregulation of TXNIP.

  4. Fenofibrate suppressed proliferation and migration of human neuroblastoma cells via oxidative stress dependent of TXNIP upregulation

    International Nuclear Information System (INIS)

    Su, Cunjin; Shi, Aiming; Cao, Guowen; Tao, Tao; Chen, Ruidong; Hu, Zhanhong; Shen, Zhu; Tao, Hong; Cao, Bin; Hu, Duanmin; Bao, Junjie

    2015-01-01

    There are no appropriate drugs for metastatic neuroblastoma (NB), which is the most common extra-cranial solid tumor for childhood. Thioredoxin binding protein (TXNIP), the endogenous inhibitor of ROS elimination, has been identified as a tumor suppressor in various solid tumors. It reported that fenofibrate exerts anti-tumor effects in several human cancer cell lines. However, its detail mechanisms remain unclear. The present study assessed the effects of fenofibrate on NB cells and investigated TXNIP role in its anti-tumor mechanisms. We used MTT assay to detect cells proliferation, starch wound test to investigate cells migration, H 2 DCF-DA to detect intracellular ROS, siRNA to interfere TXNIP and peroxisome proliferator-androgen receptor-alpha (PPAR-α) expression, western blot to determine protein levels, flow cytometry to analyze apoptosis. Fenofibrate suppressed proliferation and migration of NB cells, remarkably increased intracellular ROS, upregulated TXNIP expression, promoted cell apoptosis. Furthermore, inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. Our results indicated the anti-tumor role of fenofibrate on NB cells by exacerbating oxidative stress and inducing apoptosis was dependent on the upregulation of TXNIP. - Highlights: • We found that fenofibrate suppressed proliferation and migration of NB cells. • We found that fenofibrate remarkably increased intracellular ROS, upregulated TXNIP expression, and promoted cell apoptosis. • Inhibition of TXNIP expression attenuated anti-tumor effects of fenofibrate, while inhibition of PPAR-α had no influences. • Our results indicated the anti-tumor role of fenofibrate on NB cells was dependent on the upregulation of TXNIP

  5. The anti-angiogenic herbal extract from Melissa officinalis inhibits adipogenesis in 3T3-L1 adipocytes and suppresses adipocyte hypertrophy in high fat diet-induced obese C57BL/6J mice.

    Science.gov (United States)

    Woo, Sangee; Yoon, Miso; Kim, Jeongjun; Hong, Yeonhee; Kim, Min-Young; Shin, Soon Shik; Yoon, Michung

    2016-02-03

    Melissa officinalis L. (Labiatae; lemon balm) has been used traditionally and contemporarily as an anti-stress herb. Current hypotheses suggest that not only chronic stress promotes angiogenesis, but angiogenesis also modulates adipogenesis and obesity. Because the herbal extract ALS-L1023 from M. officinalis L. (Labiatae; lemon balm) has an anti-angiogenic activity, we hypothesized that ALS-L1023 could inhibit adipogenesis and adipocyte hypertrophy. ALS-L1023 was prepared by a two-step organic solvent fractionation from M. officinalis. The effects of ALS-L1023 on adipogenesis in 3T3-L1 adipocytes and adipocyte hypertrophy in high fat diet (HFD)-fed obese mice were measured using in vivo and in vitro approaches. ALS-L1023 inhibited angiogenesis in a dose-dependent manner in the HUVEC tube formation assay in vitro. Treatment of cells with ALS-L1023 inhibited lipid accumulation and adipocyte-specific gene expression caused by troglitazone or MDI differentiation mix. ALS-L1023 reduced mRNA expression of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9) in differentiated cells. In contrast, mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) increased. Protease activity, as measured by zymography, showed that activity of MMP-2 and MMP-9 decreased in ALS-L1023-treated cells. ALS-L1023 also inhibited MMP-2 and MMP-9 reporter gene expression in the presence of the MMP inducer phorbol 12-myristate 13-acetate. An in vivo study showed that ALS-L1023 not only decreased adipose tissue mass and adipocyte size, but also reduced mRNA levels of adipose tissue angiogenic factors and MMPs in HFD-fed obese mice. These results suggest that the anti-angiogenic herbal extract ALS-L1023 suppresses adipogenesis and adipocyte hypertrophy, and this effect may be mediated by inhibiting angiogenesis and MMP activities. Thus, by curbing adipogenesis, anti-angiogenic ALS-L1023 yields a possible therapeutic choice for the prevention and treatment of human obesity and

  6. Adipocyte-specific blockade of gamma-secretase, but not inhibition of Notch activity, reduces adipose insulin sensitivity

    Directory of Open Access Journals (Sweden)

    David P. Sparling

    2016-02-01

    Conclusions: Notch signaling is dispensable for normal adipocyte function, but adipocyte-specific γ-secretase blockade reduces adipose insulin sensitivity, suggesting that specific Notch inhibitors would be preferable to GSIs for application in T2D.

  7. Zanthoxylum schinifolium leaf ethanol extract inhibits adipocyte differentiation through inactivation of the extracellular signal regulated kinase and phosphoinositide 3-kinase/Akt signaling pathways in 3T3-L1 pre-adipocytes.

    Science.gov (United States)

    Choi, Eun-Ok; Park, Cheol; Shin, Soon Shik; Cho, Eun-Ju; Kim, Byung Woo; Hwang, Jin Ah; Hwang, Hye-Jin; Choi, Yung Hyun

    2015-07-01

    Zanthoxylum schinifolium is widely used as a food flavoring in east Asia. Although this plant has also been used in traditional oriental medicine for the treatment of the common cold, toothache, stomach ache, diarrhea and jaundice, its anti-obesity activity remains to be elucidated. The present study investigated the effects of ethanol extract from the leaves of Z. schinifolium (EEZS) on adipocyte differentiation, and its underlying mechanism, in 3T3-L1 pre-adipocytes. The results demonstrated that EEZS effectively suppressed intracellular lipid accumulation at non-toxic concentrations, and was associated with the downregulation of several adipocyte-specific transcription factors, including peroxisome proliferation-activity receptor γ (PPARγ), CCAAT/enhancer binding protein (C/EBP)α and C/EBPβ, in a concentration-dependent manner. Furthermore, it was observed that EEZS markedly inactivated the extracellular signal-regulated protein kinase (ERK) and phosphatidylinositide 3-kinase (PI3K)/Akt pathways, which act upstream of PPARγ and C/EBPs in adipogenesis. These results suggested that EEZS inhibited lipid accumulation by downregulating the major transcription factors involved in the pathway of adipogenesis, including PPARγ, C/EBPα and C/EBPβ, via regulation of the ERK and PI3K/Akt signaling pathways in 3T3-L1 adipocyte differentiation. This indicated the potential use of EEZS as an anti-obesity agent.

  8. The use of small interfering RNAs to inhibit adipocyte differentiation in human preadipocytes and fetal-femur-derived mesenchymal cells

    International Nuclear Information System (INIS)

    Xu, Y.; Mirmalek-Sani, S.-H.; Yang, X.; Zhang, J.; Oreffo, R.O.C.

    2006-01-01

    RNA interference (RNAi) has been used in functional genomics and offers innovative approaches in the development of novel therapeutics. Human mesenchymal stem cells offer a unique cell source for tissue engineering/regeneration strategies. The current study examined the potential of small interfering RNAs (siRNA) against human peroxisome proliferator activated receptor gamma (PPARγ) to suppress adipocyte differentiation (adipogenesis) in human preadipocytes and fetal-femur-derived mesenchymal cells. Adipogenesis was investigated using cellular and biochemical analysis. Transient transfection with PPARγ-siRNA using a liposomal-based strategy resulted in a significant inhibition of adipogenesis in human preadipocytes and fetal-femur-derived mesenchymal cells, compared to controls (cell, liposomal and negative siRNA). The inhibitory effect of PPARγ-siRNA was supported by testing human PPARγ mRNA and adipogenic associated genes using reverse transcription polymerase chain reaction (RT-PCR) to adiponectin receptor 1 and 2 as well as examination of fatty acid binding protein 3 (FABP 3 ) expression, an adipocyte-specific marker. The current studies indicate that PPARγ-siRNA is a useful tool to study adipogenesis in human cells, with potential applications both therapeutic and in the elucidation of mesenchymal cell differentiation in the modulation of cell differentiation in human mesenchymal cells

  9. Comparison of the gastrointestinal absorption and bioavailability of fenofibrate and fenofibric acid in humans.

    Science.gov (United States)

    Zhu, Tong; Ansquer, Jean-Claude; Kelly, Maureen T; Sleep, Darryl J; Pradhan, Rajendra S

    2010-08-01

    This study compared the gastrointestinal (GI) absorption characteristics and absolute bioavailability of fenofibric acid and fenofibrate (which is converted to fenofibric acid in vivo) in healthy volunteers. Treatments were delivered to the proximal small bowel, distal small bowel, and colon using a site-specific delivery system (Enterion capsule) and to the stomach by oral administration of equimolar doses. Serial blood samples were collected for 120 hours postdose and assayed for plasma fenofibric acid concentrations. The absolute bioavailability of each treatment was determined relative to 50 mg of fenofibric acid administered intravenously. Plasma exposure to fenofibric acid following fenofibric acid administration was approximately 1.5 times higher than that following fenofibrate administration for delivery to the proximal and distal small bowel and following oral administration, and it was approximately 5 times higher following colon delivery. The absolute bioavailability in the stomach, proximal small bowel, distal small bowel, and colon was approximately 81%, 88%, 84%, and 78%, respectively, for fenofibric acid and 69%, 73%, 66%, and 22%, respectively, for fenofibrate (P < .0001 and P = .033 for fenofibric acid vs fenofibrate in the colon and distal small bowel, respectively). In conclusion, fenofibric acid is well absorbed throughout the GI tract and has greater bioavailability than fenofibrate in all GI regions.

  10. Inhibition of adipocyte differentiation by resistin-like molecule alpha. Biochemical characterization of its oligomeric nature

    DEFF Research Database (Denmark)

    Blagoev, Blagoy; Kratchmarova, Irina; Nielsen, Mogens M

    2002-01-01

    A novel family of cysteine-rich secreted proteins with unique tissue distribution has recently been identified. One of the members, resistin (for "resistance to insulin"), also called FIZZ3, was identified in a screen for molecules that are down-regulated in mature adipocytes upon administration...... of thiazolidinediones. The prototypical member of this family was originally identified from bronchoalveolar lavage fluid of inflamed lungs and designated FIZZ1 ("found in inflammatory zone"). This molecule was also found to be highly expressed in adipose tissue and was named resistin-like molecule alpha (RELMalpha...... as well as by mass spectrometry. In addition, RELMalpha is able to form heterooligomers with resistin but not RELMbeta. Since RELMalpha is expressed by adipose tissue and it is a secreted factor, our findings suggest that RELMalpha may be involved in the control of the adipogenesis as well...

  11. Germinated brown rice extract inhibits adipogenesis through the down-regulation of adipogenic genes in 3T3-L1 adipocytes.

    Science.gov (United States)

    Ho, Jin-Nyoung; Son, Mi-Eun; Lim, Won-Chul; Lim, Seung-Taik; Cho, Hong-Yon

    2013-09-01

    The aim of this study was to examine the anti-adipogenic effect of germinated brown rice methanol extract (GBR) in 3T3-L1 adipocytes. The GBR inhibited adipocyte differentiation was measured by Oil Red O staining and glycerol-3-phosphate dehydrogenase (GPDH) activity in a dose-dependent manner without initiating any cytotoxicity. The mRNA levels of adipogenic transcription factors such as CCAAT/enhancer binding protein (C/EBPα), proliferator-activated receptorγ (PPARγ), and sterol regulatory element-binding protein-1c (SREBP-1c), and adipogenic genes, such as fatty acid synthase (FAS), adipocyte fatty acid-binding protein (aP2), and lipoprotein lipase (LPL), were significantly down-regulated by treatment with GBR when compared to that of untreated control cells. Moreover, tumor necrosis factor-α (TNF-α) and interlukin-6 (IL-6) mRNA expressions were attenuated by GBR in mature adipocytes. These data suggest that GBR exhibits an anti-adipogenic effect through the suppression of adipogenesis in 3T3-L1 adipocytes.

  12. ApoB100-LDL acts as a metabolic signal from liver to peripheral fat causing inhibition of lipolysis in adipocytes.

    Directory of Open Access Journals (Sweden)

    Josefin Skogsberg

    Full Text Available BACKGROUND: Free fatty acids released from adipose tissue affect the synthesis of apolipoprotein B-containing lipoproteins and glucose metabolism in the liver. Whether there also exists a reciprocal metabolic arm affecting energy metabolism in white adipose tissue is unknown. METHODS AND FINDINGS: We investigated the effects of apoB-containing lipoproteins on catecholamine-induced lipolysis in adipocytes from subcutaneous fat cells of obese but otherwise healthy men, fat pads from mice with plasma lipoproteins containing high or intermediate levels of apoB100 or no apoB100, primary cultured adipocytes, and 3T3-L1 cells. In subcutaneous fat cells, the rate of lipolysis was inversely related to plasma apoB levels. In human primary adipocytes, LDL inhibited lipolysis in a concentration-dependent fashion. In contrast, VLDL had no effect. Lipolysis was increased in fat pads from mice lacking plasma apoB100, reduced in apoB100-only mice, and intermediate in wild-type mice. Mice lacking apoB100 also had higher oxygen consumption and lipid oxidation. In 3T3-L1 cells, apoB100-containing lipoproteins inhibited lipolysis in a dose-dependent fashion, but lipoproteins containing apoB48 had no effect. ApoB100-LDL mediated inhibition of lipolysis was abolished in fat pads of mice deficient in the LDL receptor (Ldlr(-/-Apob(100/100. CONCLUSIONS: Our results show that the binding of apoB100-LDL to adipocytes via the LDL receptor inhibits intracellular noradrenaline-induced lipolysis in adipocytes. Thus, apoB100-LDL is a novel signaling molecule from the liver to peripheral fat deposits that may be an important link between atherogenic dyslipidemias and facets of the metabolic syndrome.

  13. AICAR inhibits adipocyte differentiation in 3T3L1 and restores metabolic alterations in diet-induced obesity mice model

    Directory of Open Access Journals (Sweden)

    Key Lyndon

    2006-08-01

    of PPARγ, C/EBPα and ADD1/SREBP1 transcription factors in vivo though PGC1α expression was significantly induced. Conclusion This study suggests that AICAR inhibits adipocyte differentiation via downregulation of expression of adipogenic factors in vitro and reduces adipose tissue content in DIO mice by activating expression of PGC1α without inhibiting adipocyte-specific transcription factors in DIO mice.

  14. Kirenol inhibits adipogenesis through activation of the Wnt/β-catenin signaling pathway in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi-Bo [Department of Biomaterials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Song, Youngwoo; Kim, Changhee [Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Hwang, Jae-Kwan, E-mail: jkhwang@yonsei.ac.kr [Department of Biomaterials Science and Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2014-03-07

    Highlights: • Kirenol inhibits the adipogenic transcription factors and lipogenic enzymes. • Kirenol stimulates the Wnt/β-catenin signaling pathway components. • Kirenol inhibits adipogenesis through activation of the Wnt/β-catenin signaling pathway. - Abstract: Kirenol, a natural diterpenoid compound, has been reported to possess anti-oxidant, anti-inflammatory, anti-allergic, and anti-arthritic activities; however, its anti-adipogenic effect remains to be studied. The present study evaluated the effect of kirenol on anti-adipogenesis through the activation of the Wnt/β-catenin signaling pathway. Kirenol prevented intracellular lipid accumulation by down-regulating key adipogenesis transcription factors [peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding proteins α (C/EBPα), and sterol regulatory element binding protein-1c (SREBP-1c)] and lipid biosynthesis-related enzymes [fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC)], as well as adipocytokines (adiponectin and leptin). Kirenol effectively activated the Wnt/β-catenin signaling pathway, in which kirenol up-regulated the expression of low density lipoprotein receptor related protein 6 (LRP6), disheveled 2 (DVL2), β-catenin, and cyclin D1 (CCND1), while it inactivated glycogen synthase kinase 3β (GSK3β) by increasing its phosphorylation. Kirenol down-regulated the expression levels of PPARγ and C/EBPα, which were up-regulated by siRNA knockdown of β-catenin. Overall, kirenol is capable of inhibiting the differentiation and lipogenesis of 3T3-L1 adipocytes through the activation of the Wnt/β-catenin signaling pathway, suggesting its potential as natural anti-obesity agent.

  15. Propionic acid and butyric acid inhibit lipolysis and de novo lipogenesis and increase insulin-stimulated glucose uptake in primary rat adipocytes.

    Science.gov (United States)

    Heimann, Emilia; Nyman, Margareta; Degerman, Eva

    2015-01-01

    Fermentation of dietary fibers by colonic microbiota generates short-chain fatty acids (SCFAs), e.g., propionic acid and butyric acid, which have been described to have "anti-obesity properties" by ameliorating fasting glycaemia, body weight and insulin tolerance in animal models. In the present study, we therefore investigate if propionic acid and butyric acid have effects on lipolysis, de novo lipogenesis and glucose uptake in primary rat adipocytes. We show that both propionic acid and butyric acid inhibit isoproterenol- and adenosine deaminase-stimulated lipolysis as well as isoproterenol-stimulated lipolysis in the presence of a phosphodiesterase (PDE3) inhibitor. In addition, we show that propionic acid and butyric acid inhibit basal and insulin-stimulated de novo lipogenesis, which is associated with increased phosphorylation and thus inhibition of acetyl CoA carboxylase, a rate-limiting enzyme in fatty acid synthesis. Furthermore, we show that propionic acid and butyric acid increase insulin-stimulated glucose uptake. To conclude, our study shows that SCFAs have effects on fat storage and mobilization as well as glucose uptake in rat primary adipocytes. Thus, the SCFAs might contribute to healthier adipocytes and subsequently also to improved energy metabolism with for example less circulating free fatty acids, which is beneficial in the context of obesity and type 2 diabetes.

  16. Tribbles 3 inhibits brown adipocyte differentiation and function by suppressing insulin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ha-Won; Choi, Ran Hee; McClellan, Jamie L. [Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, SC 29208 (United States); Piroli, Gerardo G.; Frizzell, Norma [Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208 (United States); Tseng, Yu-Hua; Goodyear, Laurie J. [Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, MA 02215 (United States); Koh, Ho-Jin, E-mail: kohh@mailbox.sc.edu [Division of Applied Physiology, Department of Exercise Science, University of South Carolina, Columbia, SC 29208 (United States)

    2016-02-19

    Recent studies have demonstrated that adult humans have substantial amounts of functioning brown adipose tissue (BAT). Since BAT has been implicated as an anti-obese and anti-diabetic tissue, it is important to understand the signaling molecules that regulate BAT function. There has been a link between insulin signaling and BAT metabolism as deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function. Tribbles 3 (TRB3) is a pseudo kinase that has been shown to regulate metabolism and insulin signaling in multiple tissues but the role of TRB3 in BAT has not been studied. In this study, we found that TRB3 expression was present in BAT and overexpression of TRB3 in brown preadipocytes impaired differentiation and decreased expression of BAT markers. Furthermore, TRB3 overexpression resulted in significantly lower oxygen consumption rates for basal and proton leakage, indicating decreased BAT activity. Based on previous studies showing that deletion or pharmaceutical inhibition of insulin signaling impairs BAT differentiation and function, we assessed insulin signaling in brown preadipocytes and BAT in vivo. Overexpression of TRB3 in cells impaired insulin-stimulated IRS1 and Akt phosphorylation, whereas TRB3KO mice displayed improved IRS1 and Akt phosphorylation. Finally, deletion of IRS1 abolished the function of TRB3 to regulate BAT differentiation and metabolism. These data demonstrate that TRB3 inhibits insulin signaling in BAT, resulting in impaired differentiation and function. - Highlights: • TRB3 is expressed in brown adipose tissue and its expression is increased during differentiation. • Overexpression of TRB3 inhibits differentiation and its activity. • Overexpression of TRB3 in brown preadipocytes inhibits insulin signaling. • TRB3KO mice displays improved insulin signaling in brown adipose tissue. • Insulin signaling is required for the effects of TRB3 to regulate brown adipose tissue differentiation and

  17. Treatment with Fenofibrate plus a low dose of Benznidazole attenuates cardiac dysfunction in experimental Chagas disease

    Directory of Open Access Journals (Sweden)

    Ágata C. Cevey

    2017-12-01

    Full Text Available Trypanosoma cruzi induces serious cardiac alterations during the chronic infection. Intense inflammatory response observed from the beginning of infection, is critical for the control of parasite proliferation and evolution of Chagas disease. Peroxisome proliferator-activated receptors (PPAR-α, are known to modulate inflammation.In this study we investigated whether a PPAR-α agonist, Fenofibrate, improves cardiac function and inflammatory parameters in a murine model of T. cruzi infection. BALB/c mice were sequentially infected with two T. cruzi strains of different genetic background. Benznidazole, commonly used as trypanocidal drug, cleared parasites but did not preclude cardiac pathology, resembling what is found in human chronic chagasic cardiomyopathy. Fenofibrate treatment restored to normal values the ejection and shortening fractions, left ventricular end-diastolic, left ventricular end-systolic diameter, and isovolumic relaxation time. Moreover, it reduced cardiac inflammation and fibrosis, decreased the expression of pro-inflammatory (IL-6, TNF-α and NOS2 and heart remodeling mediators (MMP-9 and CTGF, and reduced serum creatine kinase activity. The fact that Fenofibrate partially inhibited NOS2 expression and NO release in the presence of a PPAR-α non-competitive inhibitor, suggested it also acted through PPAR-α-independent pathways. Since IκBα cytosolic degradation was inhibited by Fenofibrate, it can be concluded that the NFκB pathway has a role in its effects. Thus, we demonstrate that Fenofibrate acts through PPAR-α-dependent and -independent pathways.Our study shows that combined treatment with Fenofibrate plus Benznidazole is able both to reverse the cardiac dysfunction associated with the ongoing inflammatory response and fibrosis and to attain parasite clearance in an experimental model of Chagas disease. Keywords: Trypanosoma cruzi, Heart dysfunction, PPAR-α, Fenofibrate treatment, Inflammatory mediators

  18. Lactobacillus brevis OPK-3 isolated from kimchi inhibits adipogenesis and exerts anti-inflammation in 3T3-L1 adipocyte.

    Science.gov (United States)

    Park, Jeong-Eun; Oh, Suk-Heung; Cha, Youn-Soo

    2014-09-01

    Kimchi is a traditional fermented food in Korea that contains various unique microorganisms. Diverse bacteria are involved in the process of Kimchi fermentation and the healthful advantages; one of the major species is Lactobacillus. We investigated whether lactic acid bacteria isolated from Kimchi (KLAB) are capable of reducing intracellular lipid accumulation by downregulating the expression of adipogenesis and lipogenesis promoting genes in differentiating 3T3-L1 cells. KLAB (Lactobacillus brevis OPK-3) mediated dose-dependent inhibition of adipocyte differentiation, intracellular triglyceride accumulation and glycerol-3-phosphate dehydrogenase (GPDH) activity. The expression of transcription factors such as peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein α involved in adipogenesis was markedly decreased by the KLAB treatment. Terminal adipogenic marker, e.g. adipocyte fatty acid binding protein (aP2), lipoprotein lipase, liver X receptor α, leptin and GPDH were significantly downregulated by KLAB treatment compared to untreated control. Moreover, cytokine genes, such as tumor necrosis factor-α and interleukin-6 mRNA expressions level were also decreased, whereas adiponectin mRNA level was upregulated by KLAB. These results suggest that the KLAB inhibits lipid accumulation in the differentiating adipocyte through downregulating the expression of adipogenic transcription factors and other specific genes involved in lipid metabolism. © 2014 Society of Chemical Industry.

  19. Ursolic acid inhibits adipogenesis in 3T3-L1 adipocytes through LKB1/AMPK pathway.

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    Yonghan He

    Full Text Available BACKGROUND: Ursolic acid (UA is a triterpenoid compound with multiple biological functions. This compound has recently been reported to possess an anti-obesity effect; however, the mechanisms are less understood. OBJECTIVE: As adipogenesis plays a critical role in obesity, the present study was conducted to investigate the effect of UA on adipogenesis and mechanisms of action in 3T3-L1 preadipocytes. METHODS AND RESULTS: The 3T3-L1 preadipocytes were induced to differentiate in the presence or absence of UA for 6 days. The cells were determined for proliferation, differentiation, fat accumulation as well as the protein expressions of molecular targets that regulate or are involved in fatty acid synthesis and oxidation. The results demonstrated that ursolic acid at concentrations ranging from 2.5 µM to 10 µM dose-dependently attenuated adipogenesis, accompanied by reduced protein expression of CCAAT element binding protein β (C/EBPβ, peroxisome proliferator-activated receptor γ (PPARγ, CCAAT element binding protein α (C/EBPα and sterol regulatory element binding protein 1c (SREBP-1c, respectively. Ursolic acid increased the phosphorylation of acetyl-CoA carboxylase (ACC and protein expression of carnitine palmitoyltransferase 1 (CPT1, but decreased protein expression of fatty acid synthase (FAS and fatty acid-binding protein 4 (FABP4. Ursolic acid increased the phosphorylation of AMP-activated protein kinase (AMPK and protein expression of (silent mating type information regulation 2, homolog 1 (Sirt1. Further studies demonstrated that the anti-adipogenic effect of UA was reversed by the AMPK siRNA, but not by the Sirt1 inhibitor nicotinamide. Liver kinase B1 (LKB1, the upstream kinase of AMPK, was upregulated by UA. When LKB1 was silenced with siRNA or the inhibitor radicicol, the effect of UA on AMPK activation was diminished. CONCLUSIONS: Ursolic acid inhibited 3T3-L1 preadipocyte differentiation and adipogenesis through the LKB1/AMPK

  20. Bitter melon (Momordica charantia L.) inhibits adipocyte hypertrophy and down regulates lipogenic gene expression in adipose tissue of diet-induced obese rats.

    Science.gov (United States)

    Huang, Hui-Ling; Hong, Ya-Wen; Wong, You-Hong; Chen, Ying-Nien; Chyuan, Jong-Ho; Huang, Ching-Jang; Chao, Pei-Min

    2008-02-01

    Bitter melon (Momordica charantia; BM) has been shown to ameliorate diet-induced obesity and insulin resistance. To examine the effect of BM supplementation on cell size and lipid metabolism in adipose tissues, three groups of rats were respectively fed a high-fat diet supplemented without (HF group) or with 5 % lyophilised BM powder (HFB group), or with 0.01 % thiazolidinedione (TZD) (HFT group). A group of rats fed a low-fat diet was also included as a normal control. Hyperinsulinaemia and glucose intolerance were observed in the HF group but not in HFT and HFB groups. Although the number of large adipocytes (>180 microm) of both the HFB and HFT groups was significantly lower than that of the HF group, the adipose tissue mass, TAG content and glycerol-3-phosphate dehydrogenase activity of the HFB group were significantly lower than those of the HFT group, implying that BM might reduce lipogenesis in adipose tissue. Experiment 2 was then conducted to examine the expression of lipogenic genes in adipose tissues of rats fed low-fat, HF or HFB diets. The HFB group showed significantly lower mRNA levels of fatty acid synthase, acetyl-CoA carboxylase-1, lipoprotein lipase and adipocyte fatty acid-binding protein than the HF group (P effective as the anti-diabetic drug TZD. Furthermore, BM can suppress the visceral fat accumulation and inhibit adipocyte hypertrophy, which may be associated with markedly down regulated expressions of lipogenic genes in the adipose.

  1. Amelioration of Mitochondrial Dysfunction-Induced Insulin Resistance in Differentiated 3T3-L1 Adipocytes via Inhibition of NF-κB Pathways

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    Mohamad Hafizi Abu Bakar

    2014-12-01

    Full Text Available A growing body of evidence suggests that activation of nuclear factor kappa B (NF-κB signaling pathways is among the inflammatory mechanism involved in the development of insulin resistance and chronic low-grade inflammation in adipose tissues derived from obese animal and human subjects. Nevertheless, little is known about the roles of NF-κB pathways in regulating mitochondrial function of the adipose tissues. In the present study, we sought to investigate the direct effects of celastrol (potent NF-κB inhibitor upon mitochondrial dysfunction-induced insulin resistance in 3T3-L1 adipocytes. Celastrol ameliorates mitochondrial dysfunction by altering mitochondrial fusion and fission in adipocytes. The levels of oxidative DNA damage, protein carbonylation and lipid peroxidation were down-regulated. Further, the morphology and quantification of intracellular lipid droplets revealed the decrease of intracellular lipid accumulation with reduced lipolysis. Moreover, massive production of the pro-inflammatory mediators tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β were markedly depleted. Insulin-stimulated glucose uptake activity was restored with the enhancement of insulin signaling pathways. This study signified that the treatments modulated towards knockdown of NF-κB transcription factor may counteract these metabolic insults exacerbated in our model of synergy between mitochondrial dysfunction and inflammation. These results demonstrate for the first time that NF-κB inhibition modulates mitochondrial dysfunction induced insulin resistance in 3T3-L1 adipocytes.

  2. Brown Algae Polyphenol, a Prolyl Isomerase Pin1 Inhibitor, Prevents Obesity by Inhibiting the Differentiation of Stem Cells into Adipocytes.

    Science.gov (United States)

    Suzuki, Atsuko; Saeki, Toshiyuki; Ikuji, Hiroko; Uchida, Chiyoko; Uchida, Takafumi

    2016-01-01

    While screening for an inhibitor of the peptidyl prolyl cis/trans isomerase, Pin1, we came across a brown algae polyphenol that blocks the differentiation of fibroblasts into adipocytes. However, its effectiveness on the accumulation of fat in the body has never been studied. Oral administration of brown algae polyphenol to mice fed with a high fat diet, suppressed the increase in fat volume to a level observed in mice fed with a normal diet. We speculate that Pin1 might be required for the differentiation of stem cell to adipocytes. We established wild type (WT) and Pin1-/- (Pin1-KO) adipose-derived mesenchymal stem cell (ASC) lines and found that WT ASCs differentiate to adipocytes but Pin1-KO ASCs do not. Oral administration of brown algae polyphenol, a Pin1 inhibitor, reduced fat buildup in mice. We showed that Pin1 is required for the differentiation of stem cells into adipocytes. We propose that oral intake of brown algae polyphenol is useful for the treatment of obesity.

  3. Brown Algae Polyphenol, a Prolyl Isomerase Pin1 Inhibitor, Prevents Obesity by Inhibiting the Differentiation of Stem Cells into Adipocytes.

    Directory of Open Access Journals (Sweden)

    Atsuko Suzuki

    Full Text Available While screening for an inhibitor of the peptidyl prolyl cis/trans isomerase, Pin1, we came across a brown algae polyphenol that blocks the differentiation of fibroblasts into adipocytes. However, its effectiveness on the accumulation of fat in the body has never been studied.Oral administration of brown algae polyphenol to mice fed with a high fat diet, suppressed the increase in fat volume to a level observed in mice fed with a normal diet. We speculate that Pin1 might be required for the differentiation of stem cell to adipocytes. We established wild type (WT and Pin1-/- (Pin1-KO adipose-derived mesenchymal stem cell (ASC lines and found that WT ASCs differentiate to adipocytes but Pin1-KO ASCs do not.Oral administration of brown algae polyphenol, a Pin1 inhibitor, reduced fat buildup in mice. We showed that Pin1 is required for the differentiation of stem cells into adipocytes. We propose that oral intake of brown algae polyphenol is useful for the treatment of obesity.

  4. Curcumin inhibits adipogenesis in 3T3-L1 adipocytes and angiogenesis and obesity in C57/BL mice

    Science.gov (United States)

    The growth of new blood vessels or angiogenesis is necessary for the growth of adipose tissue. Dietary polyphenols may suppress growth of adipose tissue through their antiangiogenic activity and by modulating adipocyte metabolism. In the present study, we examined the effect of curcumin, a polyphen...

  5. Inhibition of 3T3-L1 adipocyte differentiation by expression of acyl-CoA-binding protein antisense RNA

    DEFF Research Database (Denmark)

    Mandrup, S; Sorensen, R V; Helledie, T

    1998-01-01

    Several lines of evidence have recently underscored the significance of fatty acids or fatty acid-derived metabolites as signaling molecules in adipocyte differentiation. The acyl-CoA-binding protein (ACBP), which functions as an intracellular acyl-CoA pool former and transporter, is induced duri...

  6. miR-146b Inhibits Glucose Consumption by Targeting IRS1 Gene in Porcine Primary Adipocytes.

    Science.gov (United States)

    Zhu, Yan-Ling; Chen, Ting; Xiong, Jia-Li; Wu, Di; Xi, Qian-Yun; Luo, Jun-Yi; Sun, Jia-Jie; Zhang, Yong-Liang

    2018-03-09

    Adipose tissue plays an important role in energy metabolism. Adipose dysfunction is closely related to obesity and type II diabetes. Glucose uptake is the key step for fat synthesis in adipocyte. miRNAs have been proven to play a crucial role in adipocyte differentiation, adipogenesis and glucose homeostasis. In this paper, we firstly reported that miR-146b decreased glucose consumption by up-regulating miR-146b in a porcine primary adipocyte model, while the inhibitor of endogenous miR-146b rescued the reduction. Then, miR-146b was predicated to target IRS1 by bioinformatics analysis, and a dual-luciferase reporter assay validated this predication. Western blot analyses indicated both IRS1 and glucose transporter type 4 (GLUT4) were down-regulated by miR-146b overexpression. Our study demonstrated that miR-146b regulated glucose homeostasis in porcine primary pre-adipocyte by targeting IRS1 , and provided new understandings on regulations of lipogenesis by miRNAs.

  7. miR-146b Inhibits Glucose Consumption by Targeting IRS1 Gene in Porcine Primary Adipocytes

    Directory of Open Access Journals (Sweden)

    Yan-Ling Zhu

    2018-03-01

    Full Text Available Adipose tissue plays an important role in energy metabolism. Adipose dysfunction is closely related to obesity and type II diabetes. Glucose uptake is the key step for fat synthesis in adipocyte. miRNAs have been proven to play a crucial role in adipocyte differentiation, adipogenesis and glucose homeostasis. In this paper, we firstly reported that miR-146b decreased glucose consumption by up-regulating miR-146b in a porcine primary adipocyte model, while the inhibitor of endogenous miR-146b rescued the reduction. Then, miR-146b was predicated to target IRS1 by bioinformatics analysis, and a dual-luciferase reporter assay validated this predication. Western blot analyses indicated both IRS1 and glucose transporter type 4 (GLUT4 were down-regulated by miR-146b overexpression. Our study demonstrated that miR-146b regulated glucose homeostasis in porcine primary pre-adipocyte by targeting IRS1, and provided new understandings on regulations of lipogenesis by miRNAs.

  8. α-Mangostin Improves Glucose Uptake and Inhibits Adipocytes Differentiation in 3T3-L1 Cells via PPARγ, GLUT4, and Leptin Expressions

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    Muhammad Taher

    2015-01-01

    Full Text Available Obesity has been often associated with the occurrence of cardiovascular diseases, type 2 diabetes, and cancer. The development of obesity is also accompanied by significant differentiation of preadipocytes into adipocytes. In this study, we investigated the activity of α-mangostin, a major xanthone component isolated from the stem bark of G. malaccensis, on glucose uptake and adipocyte differentiation of 3T3-L1 cells focusing on PPARγ, GLUT4, and leptin expressions. α-Mangostin was found to inhibit cytoplasmic lipid accumulation and adipogenic differentiation. Cells treated with 50 μM of α-mangostin reduced intracellular fat accumulation dose-dependently up to 44.4% relative to MDI-treated cells. Analyses of 2-deoxy-D-[3H] glucose uptake activity showed that α-mangostin significantly improved the glucose uptake (P<0.05 with highest activity found at 25 μM. In addition, α-mangostin increased the amount of free fatty acids (FFA released. The highest glycerol release level was observed at 50 μM of α-mangostin. qRT-PCR analysis showed reduced lipid accumulation via inhibition of PPARγ gene expression. Induction of glucose uptake and free fatty acid release by α-mangostin were accompanied by increasing mRNA expression of GLUT4 and leptin. These evidences propose that α-mangostin might be possible candidate for the effective management of obesity in future.

  9. Adipocyte Liver Kinase b1 Suppresses Beige Adipocyte Renaissance Through Class IIa Histone Deacetylase 4.

    Science.gov (United States)

    Wang, Yangmeng; Paulo, Esther; Wu, Dongmei; Wu, Yixuan; Huang, Wendong; Chawla, Ajay; Wang, Biao

    2017-12-01

    Uncoupling protein 1 + beige adipocytes are dynamically regulated by environment in rodents and humans; cold induces formation of beige adipocytes, whereas warm temperature and nutrient excess lead to their disappearance. Beige adipocytes can form through de novo adipogenesis; however, how "beiging" characteristics are maintained afterward is largely unknown. In this study, we show that beige adipocytes formed postnatally in subcutaneous inguinal white adipose tissue lost thermogenic gene expression and multilocular morphology at the adult stage, but cold restored their beiging characteristics, a phenomenon termed beige adipocyte renaissance. Ablation of these postnatal beige adipocytes inhibited cold-induced beige adipocyte formation in adult mice. Furthermore, we demonstrated that beige adipocyte renaissance was governed by liver kinase b1 and histone deacetylase 4 in white adipocytes. Although neither presence nor thermogenic function of uncoupling protein 1 + beige adipocytes contributed to metabolic fitness in adipocyte liver kinase b1-deficient mice, our results reveal an unexpected role of white adipocytes in maintaining properties of preexisting beige adipocytes. © 2017 by the American Diabetes Association.

  10. Anti-Inflammatory Effect of Spirulina platensis in Macrophages Is Beneficial for Adipocyte Differentiation and Maturation by Inhibiting Nuclear Factor-κB Pathway in 3T3-L1 Adipocytes.

    Science.gov (United States)

    Pham, Tho X; Lee, Ji-Young

    2016-06-01

    We previously showed that the organic extract of a blue-green alga, Spirulina platensis (SPE), had potent anti-inflammatory effects in macrophages. As the interplay between macrophages and adipocytes is critical for adipocyte functions, we investigated the contribution of the anti-inflammatory effects of SPE in macrophages to adipogenesis/lipogenesis in 3T3-L1 adipocytes. 3T3-L1 preadipocytes were treated with 10% conditioned medium from lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages (CMC) or LPS-stimulated, but SPE-pretreated, macrophages (CMS) at different stages of adipocyte differentiation. The expression of adipocyte differentiation markers, such as CCAAT/enhancer-binding protein α, peroxisome proliferator-activated receptor γ, and perilipin, was significantly repressed by CMC when added on day 3, while the repression was attenuated by CMS. Oil Red O staining confirmed that adipocyte maturation in CMS-treated cells, but not in CMC-treated cells, was equivalent to that of control cells. Nuclear translocation of nuclear factor κB (NF-κB) p65 was decreased by CMS compared to CMC. In lipid-laden adipocytes, CMC promoted the loss of lipid droplets, while CMS had minimal effects. Histone deacetylase 9 mRNA and protein levels were increased during adipocyte maturation, which were decreased by CMC. In conclusion, by cross-talking with adipocytes, the anti-inflammatory effects of SPE in macrophages promoted adipocyte differentiation/maturation, at least in part, by repressing the activation of NF-κB inflammatory pathways, which otherwise can be compromised in inflammatory conditions.

  11. Adipocyte induced arterial calcification is prevented with sodium thiosulfate

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Neal X., E-mail: xuechen@iupui.edu [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); O’Neill, Kalisha; Akl, Nader Kassis [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); Moe, Sharon M. [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); Roudebush VA Medical Center, Indianapolis, IN (United States)

    2014-06-20

    Highlights: • High phosphorus can induce calcification of adipocytes, even when fully differentiated. • Adipocytes can induce vascular calcification in an autocrine manner. • Sodium thiosulfate inhibits adipocyte calcification. - Abstract: Background: Calcification can occur in fat in multiple clinical conditions including in the dermis, breasts and in the abdomen in calciphylaxis. All of these are more common in patients with advanced kidney disease. Clinically, hyperphosphatemia and obesity are risk factors. Thus we tested the hypothesis that adipocytes can calcify in the presence of elevated phosphorus and/or that adipocytes exposed to phosphorus can induce vascular smooth muscle cell (VSMC) calcification. Methods: 3T3-L1 preadipocytes were induced into mature adipocytes and then treated with media containing high phosphorus. Calcification was assessed biochemically and PCR performed to determine the expression of genes for osteoblast and adipocyte differentiation. Adipocytes were also co-cultured with bovine VSMC to determine paracrine effects, and the efficacy of sodium thiosulfate was determined. Results: The results demonstrated that high phosphorus induced the calcification of differentiated adipocytes with increased expression of osteopontin, the osteoblast transcription factor Runx2 and decreased expression of adipocyte transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT-enhancer-binding protein α (CEBPα), indicating that high phosphorus led to a phenotypic switch of adipocytes to an osteoblast like phenotype. Sodium thiosulfate, dose dependently decreased adipocyte calcification and inhibited adipocyte induced increase of VSMC calcification. Co-culture studies demonstrated that adipocytes facilitated VSMC calcification partially mediated by changes of secretion of leptin and vascular endothelial growth factor (VEGF) from adipocytes. Conclusion: High phosphorus induced calcification of mature adipocytes, and

  12. Effect of fenofibrate on blood pressure reduction

    Directory of Open Access Journals (Sweden)

    A K Lipatenkova

    2013-03-01

    Full Text Available Реферат по материалам статей 1. Gilbert K, Nian H, Yu C, Luther JM, Brown NJ. Fenofibrate lowers blood pressure in salt-sensitive but not salt-resistant hypertension. J Hypertens. 2013 Apr;31(4:820-9. doi: 10.1097/HJH.0b013e32835e8227. 2. Kwang K. K. Does Fenofibrate Lower Blood Pressure? Hypertension. 2013 Mar;61(3:e27. doi: 10.1161/HYPERTENSIONAHA.111.00792.

  13. A novel flavonoid isolated from the steam-bark of Ulmus wallichiana planchon stimulates osteoblast function and inhibits osteoclast and adipocyte differentiation.

    Science.gov (United States)

    Swarnkar, Gaurav; Sharan, Kunal; Siddiqui, Jawed A; Chakravarti, Bandana; Rawat, Preeti; Kumar, Manmeet; Arya, Kamal R; Maurya, Rakesh; Chattopadhyay, Naibedya

    2011-05-11

    (2S,3S)-Aromadendrin-6-C-β-d-glucopyranoside (AG) is a novel flavonol isolated from the extract of Ulmus wallichiana (Himalayan Elm). Extract of U. wallichiana is used as a traditional medicine for rapid fracture repair in India. We characterized the mechanism of action of AG in mouse bone cells by investigating its effect on the precursors of osteoblasts, osteoclasts and adipocytes. At nanomolar concentrations, AG increased differentiation of preosteoblasts obtained from neonatal mouse calvaria. The gene expression of osteogenic markers, including runt-related transcription factor 2 (Runx-2), bone morphogenetic protein-2 (BMP-2), type I collagen and osteocalcin were elevated in the preosteoblasts. The extracellular matrix mineralization was higher in preosteoblast and bone marrow cells when AG was present in the medium. Furthermore, AG protected the differentiated osteoblasts from serum deprivation-induced apoptosis, and increased the expression of the anti-osteoclastogenic cytokine, osteoprotegerin. It inhibited osteoclast differentiation of bone marrow precursor cells to osteoclasts in the presence of receptor activator of nuclear factor kappa-B ligand (RANKL) and monocyte/macrophage-colony stimulating factor (M-CSF). Additionally, in 3T3-L1 preadipocytes, AG decreased the expression of genes involved in adipogenesis, including peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element binding protein (SREBP) and CCAAT/enhancer-binding protein alpha (CEBP/α), and induced apoptosis of differentiated adipocytes. Induction of adipogenic differentiation was also inhibited in the presence of AG. AG exhibited no estrogenic/antiestrogenic effect. Together, our data show that AG has potent osteogenic, anti-osteoclastogenic and anti-adipogenic effects, which may translate to a better skeletal outcome in postmenopausal osteoporosis. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Adipocyte Fatty Acid Binding Protein Potentiates Toxic Lipids-Induced Endoplasmic Reticulum Stress in Macrophages via Inhibition of Janus Kinase 2-dependent Autophagy.

    Science.gov (United States)

    Hoo, Ruby L C; Shu, Lingling; Cheng, Kenneth K Y; Wu, Xiaoping; Liao, Boya; Wu, Donghai; Zhou, Zhiguang; Xu, Aimin

    2017-01-17

    Lipotoxicity is implicated in the pathogenesis of obesity-related inflammatory complications by promoting macrophage infiltration and activation. Endoplasmic reticulum (ER) stress and adipocyte fatty acid binding protein (A-FABP) play key roles in obesity and mediate inflammatory activity through similar signaling pathways. However, little is known about their interplay in lipid-induced inflammatory responses. Here, we showed that prolonged treatment of palmitic acid (PA) increased ER stress and expression of A-FABP, which was accompanied by reduced autophagic flux in macrophages. Over-expression of A-FABP impaired PA-induced autophagy associating with enhanced ER stress and pro-inflammatory cytokine production, while genetic ablation or pharmacological inhibition of A-FABP reversed the conditions. PA-induced expression of autophagy-related protein (Atg)7 was attenuated in A-FABP over-expressed macrophages, but was elevated in A-FABP-deficient macrophages. Mechanistically, A-FABP potentiated the effects of PA by inhibition of Janus Kinase (JAK)2 activity, thus diminished PA-induced Atg7 expression contributing to impaired autophagy and further augmentation of ER stress. These findings suggest that A-FABP acts as autophagy inhibitor to instigate toxic lipids-induced ER stress through inhibition of JAK2-dependent autophagy, which in turn triggers inflammatory responses in macrophages. A-FABP-JAK2 axis may represent an important pathological pathway contributing to obesity-related inflammatory diseases.

  15. Molecular effect of fenofibrate on PBMC gene transcription related to lipid metabolism in patients with metabolic syndrome.

    Science.gov (United States)

    Moreno-Indias, I; Tinahones, F J; Clemente-Postigo, M; Castellano-Castillo, D; Fernández-García, J C; Macias-Gonzalez, M; Queipo-Ortuño, M I; Cardona, F

    2017-06-01

    Both fasting and postprandial hypertriglyceridaemia are considered independent risk factors for atherosclerosis. Treatment of hypertriglyceridaemia is based on fibrates, which activate the peroxisome proliferator-activated receptor alpha (PPARα). However, the metabolic pathways that activate or inhibit fibrates, and how the postprandial triglyceride levels are modified, have not yet been fully described. Accordingly, the aim of this study was to determine the feasibility of peripheral blood mononuclear cells (PBMC) to study the effects of fenofibrate in patients with the metabolic syndrome. A fat overload was given to 50 patients before and after treatment with fenofibrate for 3 months. Anthropometric and biochemical variables as well as gene expression in PBMC were analysed. After treatment with fenofibrate, we observed a decrease in both baseline and postprandial (3 h after the fat overload) levels of serum triglycerides, cholesterol and uric acid and an increase in HDL cholesterol and apolipoprotein AI levels. After treatment, there was also a rise in PPARα and RXRα expression and changes in genes regulated by PPARα, both baseline and postprandial. Furthermore, in vitro experiments showed that a PPARα agonist changed the expression of genes related with lipid metabolism. Treatment with fenofibrate reduced fasting and postprandial serum triglyceride levels, possibly through a mechanism related with an increase in the expression of RXRα and PPARα, by activating the pathways involved in the uptake and degradation of triglycerides and increasing the synthesis of apolipoprotein. These results suggest that PBMC may be useful for the easy study of fenofibrate actions. © 2017 John Wiley & Sons Ltd.

  16. Synthesis of cytochrome c oxidase 1 (SCO1) inhibits insulin sensitivity by decreasing copper levels in adipocytes.

    Science.gov (United States)

    Wei, Xiang-Bo; Guo, Liang; Liu, Yang; Zhou, Shui-Rong; Liu, Yuan; Dou, Xin; Du, Shao-Yue; Ding, Meng; Peng, Wan-Qiu; Qian, Shu-Wen; Huang, Hai-Yan; Tang, Qi-Qun

    2017-09-23

    Dysregulation of insulin signaling leads to type 2 diabetes mellitus (T2DM) and other metabolic disorders. Obesity is an important contributor to insulin resistance, and although the understanding of this relationship has improved in recent years, the mechanism of obesity-induced insulin resistance is not completely understood. Disorders of copper metabolism tend to accompany the development of obesity, which increases the risk of insulin resistance. Synthesis of cytochrome c oxidase 1 (SCO1) functions in the assembly of cytochrome c oxidase (COX) and cellular copper homeostasis. However, the role of SCO1 in the regulation of metabolism remains unknown. Here, we found that obese mice had higher expression of SCO1 and lower levels of copper in white adipose tissue (WAT) than did the control mice. Overexpression of SCO1 in adipocytes was associated with copper deficiency. Copper increased insulin sensitivity by decreasing the level of phosphatase and tensin homolog (PTEN) protein. Ectopic expression of SCO1 led to insulin resistance and was accompanied by a decrease in intracellular copper level, and addition of copper abolished the inhibitory effect of SCO1 on insulin sensitivity. Our results demonstrated a novel role of SCO1 in modulating insulin sensitivity via the regulation of copper concentration in WAT and suggested a potential therapeutic target for T2DM. Copyright © 2017. Published by Elsevier Inc.

  17. Baccharis trimera (Less. DC Exhibits an Anti-Adipogenic Effect by Inhibiting the Expression of Proteins Involved in Adipocyte Differentiation

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    Daniele de Souza Marinho do Nascimento

    2017-06-01

    Full Text Available Baccharis trimera (Less. DC (gorse is a plant popularly used for the treatment of obesity. In this study, we prepared three B. trimera extracts aqueous extract (AE, decoction (AE-D, and methanol extract (ME and investigated their antioxidant effects in six different tests and their anti-adipogenic effect in 3T3-L1 cells. The extracts showed a dose-dependent antioxidant activity in all tests. AE was the most potent antioxidant in copper and ferric ion chelation assays, whereas AE-D was the most potent in superoxide and hydroxyl radical scavenging assays, reducing power assay, and total antioxidant capacity analysis. Only ME showed a cytotoxic effect against 3T3-L1 cells. Lipid accumulation decreased in 3T3-L1 adipocytes in the presence of AE and AE-D extracts (0.5 to 1.0 mg/mL. In addition, the extracts dramatically attenuated the levels of adipogenic transcriptional factors, including CCAAT enhancer-binding protein α (C/EBPα, CCAAT enhancer-binding protein β (C/EBPβ, and gamma receptors by peroxisome proliferators (PPARγ, during adipogenesis. AE-D (1.0 mg/mL caused an approximately 90% reduction in the levels of these molecules. We propose that B. trimera has an anti-adipogenic effect and could be used in the development of functional foods.

  18. Fenofibrate dose not protect glioma cells from irradiation

    International Nuclear Information System (INIS)

    Ro, Jae Lim; Kim, Won Dong; Park, Woo Yoon

    2012-01-01

    Fenofibrate(FF) is a ligand for peroxisome proliferator-activated receptor (PPAR) α and used clinically as a hypolipidemic drug. FF has been reported to have a radioprotective effect of newborn cells in the dentate gyrus 1) and inhibit radiation-induced microglial pro-inflammatory response 2). However, if FF also protect tumor cells, it can not be used clinically during radiotherapy. Thus, we're interested in whether FF has an radioprotective effect of brain tumor cells or not Although the radiosensitive G0/G1 phase cells were increased, radiosensitization by FF was not observed in three human glioma cells. This may be due to counterbalance of radiosensitizing and radioprotecting proteins increased by FF. Taken together, FF neither radiosensitize nor radioprotect glioma cells, so it can be used to protect normal neural cells from radiation damage

  19. Centipede grass exerts anti-adipogenic activity through inhibition of C/EBPβ, C/EBPα, and PPARγ expression and the AKT signaling pathway in 3T3-L1 adipocytes

    Directory of Open Access Journals (Sweden)

    Park Hyoung Joon

    2012-11-01

    Full Text Available Abstract Background Centipede grass (CG originates from China and South America and is reported to contain several C-glycosyl flavones and phenolic constituents, including maysin and luteolin derivatives. This study aimed to investigate, for the first time, the antiobesity activity of CG and its potential molecular mechanism in 3T3-L1 cells. Methods To study the effect of CG on adipogenesis, differentiating 3T3-L1 cells were treated every day with CG at various concentrations (0–100 μg/ml for six days. Oil-red O staining and triglyceride content assay were performed to determine the lipid accumulation in 3T3-L1 cells. The expression of mRNAs or proteins associated with adipogenesis was measured using RT-PCR and Western blotting analysis. We examined the effect of CG on level of phosphorylated Akt in 3T3-L1 cells treated with CG at various concentration s during adipocyte differentiation. Results Differentiation was investigated with an Oil-red O staining assay using CG-treated 3T3-L1 adipocytes. We found that CG suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells in a dose-dependent manner. Treatment of the 3T3-L1 adipocytes with CG resulted in an attenuation of the expression of adipogenesis-related factors and lipid metabolic genes. The expression of C/EBPα and PPARγ, the central transcriptional regulators of adipogenesis, was decreased by the treatment with CG. The expression of genes involved in lipid metabolism, aP2 were significantly inhibited following the CG treatment. Moreover, the CG treatment down-regulated the phosphorylation levels of Akt and GSK3β. Conclusions Taken collectively, these data indicated that CG exerts antiadipogenic activity by inhibiting the expression of C/EBPβ, C/EBPα, and PPARγ and the Akt signaling pathway in 3T3-L1 adipocytes.

  20. Fenofibrate reduces food intake via cholecystokinin

    Directory of Open Access Journals (Sweden)

    S Yu Vorotnikova

    2012-12-01

    Full Text Available Реферат по статье: Park MK, Han Y, Kim MS, Seo E, Kang S, Park SY, Koh H, Kim DK, Lee HJ. Reduction of Food Intake by Fenofibrate is Associated with Cholecystokinin Release in Long-Evans Tokushima Rats. Korean J Physiol Pharmacol. 2012 Jun;16(3:181-6.

  1. Endoplasmic reticulum stress involved in high-fat diet and palmitic acid-induced vascular damages and fenofibrate intervention

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yunxia, E-mail: wwwdluyx@sina.com [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Cheng, Jingjing [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Chen, Li [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Department of Medical Laboratory, Anhui Provincial Hospital, Hefei, Anhui 230001 (China); Li, Chaofei; Chen, Guanjun [Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, Anhui 230032 (China); Gui, Li [The Comprehensive Laboratory, Anhui Medical University, Hefei, Anhui 230032 (China); Shen, Bing [Department of Physiology, Anhui Medical University, Hefei, Anhui 230032 (China); Zhang, Qiu [Department of Endocrinology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022 (China)

    2015-02-27

    Fenofibrate (FF) is widely used to lower blood lipids in clinical practice, but whether its protective effect on endothelium-dependent vasodilatation (EDV) in thoracic aorta is related with endoplasmic reticulum (ER) stress remains unknown. In this study, female Sprauge Dawley rats were divided into standard chow diets (SCD), high-fat diets (HFD) and HFD plus FF treatment group (HFD + FF) randomly. The rats of latter two groups were given HFD feeding for 5 months, then HFD + FF rats were treated with FF (30 mg/kg, once daily) via gavage for another 2 months. The pathological and tensional changes, protein expression of eNOS, and ER stress related genes in thoracic aorta were measured. Then impacts of palmitic acid (PA) and FF on EDV of thoracic aorta from normal female SD rats were observed. Ultimately the expression of ER stress related genes were assessed in primary mouse aortic endothelial cells (MAEC) treated by fenofibric acid (FA) and PA. We found that FF treatment improved serum lipid levels and pathological changes in thoracic aorta, accompanied with decreased ER stress and increased phosphorylation of eNOS. FF pretreatment also improved EDV impaired by different concentrations of PA treatment. The dose- and time-dependent inhibition of cell proliferation by PA were inverted by FA pretreatment. Phosphorylation of eNOS and expression of ER stress related genes were all inverted by FA pretreatment in PA-treated MAEC. Our findings show that fenofibrate recovers damaged EDV by chronic HFD feeding and acute stimulation of PA, this effect is related with decreased ER stress and increased phosphorylation of eNOS. - Highlights: • Fenofibrate treatment improved pathological changes in thoracic aorta by chronic high-fat-diet feeding. • Fenofibrate pretreatment improved endothelium-dependent vasodilation impaired by different concentrations of palmitic acid. • The inhibition of proliferation in endothelial cells by palmitic acid were inverted by fenofibric

  2. Buddleja officinalis Maximowicz Extract Inhibits Lipid Accumulation on Adipocyte Differentiation in 3T3-L1 Cells and High-Fat Mice

    Directory of Open Access Journals (Sweden)

    Jin-Kyu Kim

    2012-07-01

    Full Text Available Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited lipid accumulation during 3T3-L1 adipocyte differentiation. Furthermore, Buddleja officinalis Maximowicz extract reduced the body weight gain induced through feeding a high-fat diet to C57BL/6 mice. The treatment of Buddleja officinalis Maximowicz extract significantly reduced the adipose tissue weight to 2.7/100 g of body weight in high-fat mice. When their adipose tissue morphology was investigated for histochemical staining, the distribution of cell size in the high-fat diet groups was hypertrophied compared with those from Buddleja officinalis Maximowicz extract-treated mice. In addition, in Buddleja officinalis Maximowicz extract-treated mice, a significant reduction of serum triglyceride and T-cholesterol was observed at to 21% and 17%, respectively. The discovery of bioactive compounds from diet or dietary supplementation is one of possible ways to control obesity and to prevent or reduce the risks of various obesity-related diseases. These results support that Buddleja officinalis Maximowicz extract is expected to create the therapeutic interest with respect to the treatment of obesity.

  3. Buddleja officinalis Maximowicz extract inhibits lipid accumulation on adipocyte differentiation in 3T3-L1 cells and high-fat mice.

    Science.gov (United States)

    Roh, Changhyun; Park, Min-Kyoung; Shin, Hee-June; Jung, Uhee; Kim, Jin-Kyu

    2012-07-23

    Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited lipid accumulation during 3T3-L1 adipocyte differentiation. Furthermore, Buddleja officinalis Maximowicz extract reduced the body weight gain induced through feeding a high-fat diet to C57BL/6 mice. The treatment of Buddleja officinalis Maximowicz extract significantly reduced the adipose tissue weight to 2.7/100 g of body weight in high-fat mice. When their adipose tissue morphology was investigated for histochemical staining, the distribution of cell size in the high-fat diet groups was hypertrophied compared with those from Buddleja officinalis Maximowicz extract-treated mice. In addition, in Buddleja officinalis Maximowicz extract-treated mice, a significant reduction of serum triglyceride and T-cholesterol was observed at to 21% and 17%, respectively. The discovery of bioactive compounds from diet or dietary supplementation is one of possible ways to control obesity and to prevent or reduce the risks of various obesity-related diseases. These results support that Buddleja officinalis Maximowicz extract is expected to create the therapeutic interest with respect to the treatment of obesity.

  4. Hyperosmotic stress inhibits insulin receptor substrate-1 function by distinct mechanisms in 3T3-L1 adipocytes

    DEFF Research Database (Denmark)

    Gual, Philippe; Gonzalez, Teresa; Grémeaux, Thierry

    2003-01-01

    . Furthermore, the mammalian target of rapamycin (mTOR) inhibitor rapamycin prevented the osmotic shock-induced phosphorylation of IRS-1 on Ser307. The inhibition of mTOR completely reversed the inhibitory effect of hyperosmotic stress on insulin-induced IRS-1 tyrosine phosphorylation and PI 3-kinase activation....... In addition, prolonged osmotic stress enhanced the degradation of IRS proteins through a rapamycin-insensitive pathway and a proteasome-independent process. These data support evidence of new mechanisms involved in osmotic stress-induced cellular insulin resistance. Short-term osmotic stress induces...... the phosphorylation of IRS-1 on Ser307 by an mTOR-dependent pathway. This, in turn, leads to a decrease in early proximal signaling events induced by physiological insulin concentrations. On the other hand, prolonged osmotic stress alters IRS-1 function by inducing its degradation, which could contribute to the down...

  5. Effect of Ganoderma applanatum mycelium extract on the inhibition of adipogenesis in 3T3-L1 adipocytes.

    Science.gov (United States)

    Kim, Ji-Eun; Park, Sung-Jin; Yu, Mi-Hee; Lee, Sam-Pin

    2014-10-01

    Ganoderma applanatum (GA) and related fungal species have been used for over 2000 years in China to prevent and treat various human diseases. However, there is no critical research evaluating the functionality of GA grown using submerged culture technology. This study aimed to evaluate the effects of submerged culture GA mycelium (GAM) and its active components (protocatechualdehyde [PCA]) on preadipocyte differentiation of 3T3-L1 cells. Mouse-derived preadipocyte 3T3-L1 cells were treated with differentiation inducers in the presence or absence of GAM extracts. We determined triglyceride accumulations, glycerol-3-phosphate dehydrogenase (GPDH) activities, and differentiation makers. PCA, the active component of GAM extract, was also used to treat 3T3-L1 cells. The MTT assay showed that the GAM extract (0.01-1 mg/mL) was not toxic to 3T3-L1 preadipocyte. Treatment of cells with GAM extracts and its active components significantly decreased the GPDH activity and lipid accumulation, a marker of adipogenesis, in a dose-dependent manner. Western blot analysis results showed that the protein expression levels of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP1) were inhibited by the GAM extract. In addition, adipogenic-specific genes such as perilipin, fatty acid synthase (FAS), fatty acid transport protein 1 (FATP1), and fatty acid-binding protein 4 (FABP4) decreased in a dose-dependent manner. Quantitative high-performance liquid chromatography analysis showed that the GAM extract contained 1.14 mg/g PCA. GAM extracts suppressed differentiation of 3T3-L1 preadipocytes, in part, through altered regulation of PPARγ, C/EBPα, and SREBP1. These results suggest that GAM extracts and PCA may suppress adipogenesis by inhibiting differentiation of preadipocytes.

  6. Effect of magnesium carbonate on the solubility, dissolution and oral bioavailability of fenofibric acid powder as an alkalising solubilizer.

    Science.gov (United States)

    Kim, Kyeong Soo; Kim, Jeong Hyun; Jin, Sung Giu; Kim, Dong Wuk; Kim, Dong Shik; Kim, Jong Oh; Yong, Chul Soon; Cho, Kwan Hyung; Li, Dong Xun; Woo, Jong Soo; Choi, Han-Gon

    2016-04-01

    To investigate the possibility of developing a novel oral pharmaceutical product using fenofibric acid instead of choline fenofibrate, the powder properties, solubility, dissolution and pharmacokinetics in rats of fenofibrate, choline fenofibrate and fenofibric acid were compared. Furthermore, the effect of magnesium carbonate, an alkalising agent on the solubility, dissolution and oral bioavailability of fenofibric acid was assessed, a mixture of fenofibric acid and magnesium carbonate being prepared by simple blending at a weight ratio of 2/1. The three fenofibrate derivatives showed different particle sizes and melting points with similar crystalline shape. Fenofibric acid had a significantly higher aqueous solubility and dissolution than fenofibrate, but significantly lower solubility and dissolution than choline fenofibrate. However, the fenofibric acid/magnesium carbonate mixture greatly improved the solubility and dissolution of fenofibric acid with an enhancement to levels similar with those for choline fenofibrate. Fenofibric acid gave lower plasma concentrations, AUC and Cmax values compared to choline fenofibrate in rats. However, the mixture resulted in plasma concentrations, AUC and Cmax values levels not significantly different from those for choline fenofibrate. Specifically, magnesium carbonate increased the aqueous solubility, dissolution and bioavailability of fenofibric acid by about 7.5-, 4- and 1.6-fold, respectively. Thus, the mixture of fenofibric acid and magnesium carbonate at the weight ratio of 2/1 might be a candidate for an oral pharmaceutical product with improved oral bioavailability.

  7. ER Stress and Lipid Metabolism in Adipocytes

    Directory of Open Access Journals (Sweden)

    Beth S. Zha

    2012-01-01

    Full Text Available The role of endoplasmic reticulum (ER stress is a rapidly emerging field of interest in the pathogenesis of metabolic diseases. Recent studies have shown that chronic activation of ER stress is closely linked to dysregulation of lipid metabolism in several metabolically important cells including hepatocytes, macrophages, β-cells, and adipocytes. Adipocytes are one of the major cell types involved in the pathogenesis of the metabolic syndrome. Recent advances in dissecting the cellular and molecular mechanisms involved in the regulation of adipogenesis and lipid metabolism indicate that activation of ER stress plays a central role in regulating adipocyte function. In this paper, we discuss the current understanding of the potential role of ER stress in lipid metabolism in adipocytes. In addition, we touch upon the interaction of ER stress and autophagy as well as inflammation. Inhibition of ER stress has the potential of decreasing the pathology in adipose tissue that is seen with energy overbalance.

  8. Brown adipocyte function

    DEFF Research Database (Denmark)

    Winther, Sally

    that glycolytic flux is important for β-adrenergically induced oxygen consumption, and highlights that glucose oxidation serves multiple purposes in brown adipocytes. Together the studies describe novel aspects of glucose consumption adding to the understanding of substrate oxidation in activated brown adipocytes....... Taken together the research presented in this thesis describes novel aspects of BAT physiology, adding to the growing understanding of brown adipocyte activation and fuel preferences....

  9. SOCS-3 is involved in the downregulation of the acute insulin-like effects of growth hormone in rat adipocytes by inhibition of Jak2/IRS-1 signaling

    DEFF Research Database (Denmark)

    Ridderstråle, M; Amstrup, J; Hilton, D J

    2003-01-01

    One of the long-term effects of growth hormone (GH) in adipocytes is to maintain a state of refractoriness to insulin-like effects, a refractoriness which otherwise declines within a few hours of GH starvation. Here, we examined differences in GH signaling and the possible role for the recently i...

  10. Inhibition of fat cell differentiation in 3T3-L1 pre-adipocytes by all-trans retinoic acid: Integrative analysis of transcriptomic and phenotypic data.

    Science.gov (United States)

    Stoecker, Katharina; Sass, Steffen; Theis, Fabian J; Hauner, Hans; Pfaffl, Michael W

    2017-03-01

    The process of adipogenesis is controlled in a highly orchestrated manner, including transcriptional and post-transcriptional events. In developing 3T3-L1 pre-adipocytes, this program can be interrupted by all-trans retinoic acid (ATRA). To examine this inhibiting impact by ATRA, we generated large-scale transcriptomic data on the microRNA and mRNA level. Non-coding RNAs such as microRNAs represent a field in RNA turnover, which is very important for understanding the regulation of mRNA gene expression. High throughput mRNA and microRNA expression profiling was performed using mRNA hybridisation microarray technology and multiplexed expression assay for microRNA quantification. After quantitative measurements we merged expression data sets, integrated the results and analysed the molecular regulation of in vitro adipogenesis. For this purpose, we applied local enrichment analysis on the integrative microRNA-mRNA network determined by a linear regression approach. This approach includes the target predictions of TargetScan Mouse 5.2 and 23 pre-selected, significantly regulated microRNAs as well as Affymetrix microarray mRNA data. We found that the cellular lipid metabolism is negatively affected by ATRA. Furthermore, we were able to show that microRNA 27a and/or microRNA 96 are important regulators of gap junction signalling, the rearrangement of the actin cytoskeleton as well as the citric acid cycle, which represent the most affected pathways with regard to inhibitory effects of ATRA in 3T3-L1 preadipocytes. In conclusion, the experimental workflow and the integrative microRNA-mRNA data analysis shown in this study represent a possibility for illustrating interactions in highly orchestrated biological processes. Further the applied global microRNA-mRNA interaction network may also be used for the pre-selection of potential new biomarkers with regard to obesity or for the identification of new pharmaceutical targets.

  11. How Abbott’s Fenofibrate Franchise Avoided Generic Competition

    Science.gov (United States)

    Downing, Nicholas S.; Ross, Joseph S.; Jackevicius, Cynthia A.; Krumholz, Harlan M.

    2013-01-01

    The ongoing debate concerning the efficacy of fenofibrate has overshadowed an important aspect of the drug’s history: Abbott, the maker of branded fenofibrate, has produced several bioequivalent reformulations, which dominate the market even though generic fenofibrate has been available for almost a decade. This continued use of branded formulations, which cost twice as much as generic versions of fenofibrate, imposes an annual cost of approximately $700 million on our healthcare system. Abbott maintained its dominance of the fenofibrate market, in part, through a complex switching strategy involving the sequential launch of branded reformulations that had not been shown to be superior to the first generation product and patent litigation that delayed the approval of generic formulations. The small differences in dose of the newer branded formulations prevented substitution with generics of older generation products. As soon as direct generic competition seemed likely at the new dose level where substitution would be allowed, Abbott would launch another reformulation and the cycle would repeat. Our objective, using the fenofibrate example, is to describe how current policy can allow pharmaceutical companies to maintain market share using reformulations of branded medications without demonstrating the superiority of next generation products. PMID:22493409

  12. Avoidance of generic competition by Abbott Laboratories' fenofibrate franchise.

    Science.gov (United States)

    Downing, Nicholas S; Ross, Joseph S; Jackevicius, Cynthia A; Krumholz, Harlan M

    2012-05-14

    The ongoing debate concerning the efficacy of fenofibrate has overshadowed an important aspect of the drug's history: Abbott Laboratories, the maker of branded fenofibrate, has produced several bioequivalent reformulations that dominate the market, although generic fenofibrate has been available for almost a decade. This continued use of branded formulations, which cost twice as much as generic versions of fenofibrate, imposes an annual cost of approximately $700 million on the US health care system. Abbott Laboratories maintained its dominance of the fenofibrate market in part through a complex switching strategy involving the sequential launch of branded reformulations that had not been shown to be superior to the first-generation product and patent litigation that delayed the approval of generic formulations. The small differences in dose of the newer branded formulations prevented their substitution with generics of older-generation products. As soon as direct generic competition seemed likely at the new dose level, where substitution would be allowed, Abbott would launch another reformulation, and the cycle would repeat. Based on the fenofibrate example, our objective is to describe how current policy can allow pharmaceutical companies to maintain market share using reformulations of branded medications, without demonstrating the superiority of next-generation products.

  13. Suppression of Fatty Acid and Triglyceride Synthesis by the Flavonoid Orientin through Decrease of C/EBPδ Expression and Inhibition of PI3K/Akt-FOXO1 Signaling in Adipocytes

    Directory of Open Access Journals (Sweden)

    Shiori Nagai

    2018-01-01

    Full Text Available Plant flavonoids have a variety of biological properties. In a previous study, we found that the tea of the Asian dayflower, Commelina communis L., decreased the body weight gain in high-fat diet-fed mice. In this study, we studied the anti-adipogenic ability of a flavonoid orientin that is found in abundance in C. communis. Orientin repressed the accumulation of intracellular triglyceride (TG in mouse adipocyte 3T3-L1 cells. The treatment with orientin also decreased the mRNA levels of the genes involved in adipogenesis, lipogenesis, lipolysis, and TG synthesis, and reduced the release of glycerol. Orientin lowered the expression of CCAAT/enhancer binding protein (C/EBP δ in the early stage of adipogenesis, leading to a decrease in the expression of the adipogenic master transcription factors such as peroxisome proliferator-activated receptor (PPAR γ and C/EBPα. Moreover, the anti-adipogenic effect of orientin repressed the phosphorylation of Akt and subsequent phosphorylation of forkhead box protein O1 (FOXO1, which inhibits the transcription of the Ppar gene. These results indicate that a plant flavonoid orientin suppressed the expression of the Pparγ gene through repression of C/ebpδ expression and inhibition of the phosphoinositide 3-kinase /Akt-FOXO1 signaling in adipocytes.

  14. Propionic acid and butyric acid inhibit lipolysis and de novo lipogenesis and increase insulin-stimulated glucose uptake in primary rat adipocytes.

    OpenAIRE

    Heimann, Emilia; Nyman, Margareta; Degerman, Eva

    2015-01-01

    Fermentation of dietary fibers by colonic microbiota generates short-chain fatty acids (SCFAs), e.g., propionic acid and butyric acid, which have been described to have "anti-obesity properties" by ameliorating fasting glycaemia, body weight and insulin tolerance in animal models. In the present study, we therefore investigate if propionic acid and butyric acid have effects on lipolysis, de novo lipogenesis and glucose uptake in primary rat adipocytes. We show that both propionic ac...

  15. Food additives such as sodium sulphite, sodium benzoate and curcumin inhibit leptin release in lipopolysaccharide-treated murine adipocytes in vitro.

    Science.gov (United States)

    Ciardi, Christian; Jenny, Marcel; Tschoner, Alexander; Ueberall, Florian; Patsch, Josef; Pedrini, Michael; Ebenbichler, Christoph; Fuchs, Dietmar

    2012-03-01

    Obesity leads to the activation of pro-inflammatory pathways, resulting in a state of low-grade inflammation. Recently, several studies have shown that the exposure to lipopolysaccharide (LPS) could initiate and maintain a chronic state of low-grade inflammation in obese people. As the daily intake of food additives has increased substantially, the aim of the present study was to investigate a potential influence of food additives on the release of leptin, IL-6 and nitrite in the presence of LPS in murine adipocytes. Leptin, IL-6 and nitrite concentrations were analysed in the supernatants of murine 3T3-L1 adipocytes after co-incubation with LPS and the food preservatives, sodium sulphite (SS), sodium benzoate (SB) and the spice and colourant, curcumin, for 24 h. In addition, the kinetics of leptin secretion was analysed. A significant and dose-dependent decrease in leptin was observed after incubating the cells with SB and curcumin for 12 and 24 h, whereas SS decreased leptin concentrations after 24 h of treatment. Moreover, SS increased, while curcumin decreased LPS-stimulated secretion of IL-6, whereas SB had no such effect. None of the compounds that were investigated influenced nitrite production. The food additives SS, SB and curcumin affect the leptin release after co-incubation with LPS from cultured adipocytes in a dose- and time-dependent manner. Decreased leptin release during the consumption of nutrition-derived food additives could decrease the amount of circulating leptin to which the central nervous system is exposed and may therefore contribute to an obesogenic environment.

  16. Significance and suppression of redundant IL17 responses in acute allograft rejection by bioinformatics based drug repositioning of fenofibrate.

    Directory of Open Access Journals (Sweden)

    Silke Roedder

    Full Text Available Despite advanced immunosuppression, redundancy in the molecular diversity of acute rejection (AR often results in incomplete resolution of the injury response. We present a bioinformatics based approach for identification of these redundant molecular pathways in AR and a drug repositioning approach to suppress these using FDA approved drugs currently available for non-transplant indications. Two independent microarray data-sets from human renal allograft biopsies (n = 101 from patients on majorly Th1/IFN-y immune response targeted immunosuppression, with and without AR, were profiled. Using gene-set analysis across 3305 biological pathways, significant enrichment was found for the IL17 pathway in AR in both data-sets. Recent evidence suggests IL17 pathway as an important escape mechanism when Th1/IFN-y mediated responses are suppressed. As current immunosuppressions do not specifically target the IL17 axis, 7200 molecular compounds were interrogated for FDA approved drugs with specific inhibition of this axis. A combined IL17/IFN-y suppressive role was predicted for the antilipidemic drug Fenofibrate. To assess the immunregulatory action of Fenofibrate, we conducted in-vitro treatment of anti-CD3/CD28 stimulated human peripheral blood cells (PBMC, and, as predicted, Fenofibrate reduced IL17 and IFN-γ gene expression in stimulated PMBC. In-vivo Fenofibrate treatment of an experimental rodent model of cardiac AR reduced infiltration of total leukocytes, reduced expression of IL17/IFN-y and their pathway related genes in allografts and recipients' spleens, and extended graft survival by 21 days (p<0.007. In conclusion, this study provides important proof of concept that meta-analyses of genomic data and drug databases can provide new insights into the redundancy of the rejection response and presents an economic methodology to reposition FDA approved drugs in organ transplantation.

  17. De Novo Synthesis of Steroids and Oxysterols in Adipocytes*

    Science.gov (United States)

    Li, Jiehan; Daly, Edward; Campioli, Enrico; Wabitsch, Martin; Papadopoulos, Vassilios

    2014-01-01

    Local production and action of cholesterol metabolites such as steroids or oxysterols within endocrine tissues are currently recognized as an important principle in the cell type- and tissue-specific regulation of hormone effects. In adipocytes, one of the most abundant endocrine cells in the human body, the de novo production of steroids or oxysterols from cholesterol has not been examined. Here, we demonstrate that essential components of cholesterol transport and metabolism machinery in the initial steps of steroid and/or oxysterol biosynthesis pathways are present and active in adipocytes. The ability of adipocyte CYP11A1 in producing pregnenolone is demonstrated for the first time, rendering adipocyte a steroidogenic cell. The oxysterol 27-hydroxycholesterol (27HC), synthesized by the mitochondrial enzyme CYP27A1, was identified as one of the major de novo adipocyte products from cholesterol and its precursor mevalonate. Inhibition of CYP27A1 activity or knockdown and deletion of the Cyp27a1 gene induced adipocyte differentiation, suggesting a paracrine or autocrine biological significance for the adipocyte-derived 27HC. These findings suggest that the presence of the 27HC biosynthesis pathway in adipocytes may represent a defense mechanism to prevent the formation of new fat cells upon overfeeding with dietary cholesterol. PMID:24280213

  18. De novo synthesis of steroids and oxysterols in adipocytes.

    Science.gov (United States)

    Li, Jiehan; Daly, Edward; Campioli, Enrico; Wabitsch, Martin; Papadopoulos, Vassilios

    2014-01-10

    Local production and action of cholesterol metabolites such as steroids or oxysterols within endocrine tissues are currently recognized as an important principle in the cell type- and tissue-specific regulation of hormone effects. In adipocytes, one of the most abundant endocrine cells in the human body, the de novo production of steroids or oxysterols from cholesterol has not been examined. Here, we demonstrate that essential components of cholesterol transport and metabolism machinery in the initial steps of steroid and/or oxysterol biosynthesis pathways are present and active in adipocytes. The ability of adipocyte CYP11A1 in producing pregnenolone is demonstrated for the first time, rendering adipocyte a steroidogenic cell. The oxysterol 27-hydroxycholesterol (27HC), synthesized by the mitochondrial enzyme CYP27A1, was identified as one of the major de novo adipocyte products from cholesterol and its precursor mevalonate. Inhibition of CYP27A1 activity or knockdown and deletion of the Cyp27a1 gene induced adipocyte differentiation, suggesting a paracrine or autocrine biological significance for the adipocyte-derived 27HC. These findings suggest that the presence of the 27HC biosynthesis pathway in adipocytes may represent a defense mechanism to prevent the formation of new fat cells upon overfeeding with dietary cholesterol.

  19. Role of Foxa-2 in adipocyte metabolism and differentiation

    OpenAIRE

    Wolfrum, Christian; Shih, David Q.; Kuwajima, Satoru; Norris, Andrew W.; Kahn, C. Ronald; Stoffel, Markus

    2003-01-01

    Hepatocyte nuclear factors-3 (Foxa-1–3) are winged forkhead transcription factors that regulate gene expression in the liver and pancreatic islets and are required for normal metabolism. Here we show that Foxa-2 is expressed in preadipocytes and induced de novo in adipocytes of genetic and diet-induced rodent models of obesity. In preadipocytes Foxa-2 inhibits adipocyte differentiation by activating transcription of the Pref-1 gene. Foxa-2 and Pref-1 expression can be enhanced in primary prea...

  20. Understanding the solid-state forms of fenofibrate - A spectroscopic and computational study

    DEFF Research Database (Denmark)

    Heinz, Andrea; Gordon, Keith C.; McGoverin, Cushla M.

    2009-01-01

    The aim of this study was to investigate the structure of different solid-state forms of fenofibrate, a drug that lacks strong intermolecular interactions such as hydrogen bonding. In addition to a structural analysis of crystalline and amorphous fenofibrate using infrared and Raman spectroscopy...... combined with density functional theory calculations [B3LYP 6-31G(d)], solid-state changes that occur upon recrystallization of amorphous fenofibrate were monitored and described using in situ Raman spectroscopy. A comparison of the calculated vibrational spectra of a fenofibrate monomer and two dimer...... structures with the experimental vibrational spectra of crystalline and amorphous fenofibrate revealed conformational differences in the orientation of the two benzyl rings in the fenofibrate molecule and structural differences between the different solid-state forms in aliphatic parts of the drug molecule...

  1. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Minchul Seo

    2017-02-01

    Full Text Available Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor, the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90% upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  2. Tenebrio molitor Larvae Inhibit Adipogenesis through AMPK and MAPKs Signaling in 3T3-L1 Adipocytes and Obesity in High-Fat Diet-Induced Obese Mice.

    Science.gov (United States)

    Seo, Minchul; Goo, Tae-Won; Chung, Mi Yeon; Baek, Minhee; Hwang, Jae-Sam; Kim, Mi-Ae; Yun, Eun-Young

    2017-02-28

    Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor , the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90%) upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP)-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.

  3. Fenofibrate activates Nrf2 through p62-dependent Keap1 degradation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Su [Severance Biomedical Science Institute (Korea, Republic of); Yonsei Biomedical Research Institute, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Kang, Dong Hoon [Department of Life Science and Ewha Research Center for Systems Biology (Korea, Republic of); The Research Center for Cell Homeostasis, Ewha Womans University, Seoul 127-750 (Korea, Republic of); Lee, Da Hyun [Severance Biomedical Science Institute (Korea, Republic of); Yonsei Biomedical Research Institute, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Bae, Soo Han, E-mail: soohanbae@yuhs.ac [Severance Biomedical Science Institute (Korea, Republic of); Yonsei Biomedical Research Institute, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752 (Korea, Republic of)

    2015-09-25

    Peroxisome proliferator-activated receptor α (PPARα) activates the β-oxidation of fatty acids in the liver. Fenofibrate is a potent agonist of PPARα and is used in the treatment of hyperlipidemia. Fenofibrate treatment often induces the production of intracellular reactive oxygen species (ROS), leading to cell death. The nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (Keap1) pathway is an essential component of the defense mechanism against oxidative stress. However, the molecular mechanism underlying the regulation of the Nrf2-Keap1 pathway in fenofibrate-induced cell death is not known. In this study, we demonstrated that fenofibrate induces Keap1 degradation and Nrf2 activation. This fenofibrate-mediated Keap1 degradation is partly dependent on autophagy. Furthermore, fenofibrate-induced Keap1 degradation followed by Nrf2 activation is mainly mediated by p62, which functions as an adaptor protein in the autophagic pathway. Consistent with these findings, ablation of p62 increased fenofibrate-mediated apoptotic cell death associated with ROS accumulation. These results strongly suggest that p62 plays a crucial role in preventing fenofibrate-induced cell death. - Highlights: • Fenofibrate induces cell death by increasing ROS production. • The underlying defense mechanism against this effect is unknown. • Fenofibrate induces autophagy-dependent Keap1 degradation and Nrf2 activation. • This process is p62-dependent; lack of p62 enhanced fenofibrate-mediated apoptosis. • p62 plays a crucial role in preventing fenofibrate-induced cell death.

  4. The anti-obesity effects of a tuna peptide on 3T3-L1 adipocytes are mediated by the inhibition of the expression of lipogenic and adipogenic genes and by the activation of the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Kim, Young-Min; Kim, In-Hye; Choi, Jeong-Wook; Lee, Min-Kyeong; Nam, Taek-Jeong

    2015-08-01

    The differentiation of 3T3-L1 cells into adipocytes involves the activation of an organized system of obesity-related genes, of which those encoding CCAAT/enhancer-binding proteins (C/EBPs) and the Wnt-10b protein may play integral roles. In a previous study of ours, we found that a specific peptide found in tuna (sequence D-I-V-D-K-I-E-I; termed TP-D) inhibited 3T3-L1 cell differentiation. In the present study, we observed that the expression of expression of C/EBPs and Wnt-10b was associated with obesity. The initial step of 3T3-L1 cell differentiation involved the upregulation of C/EBP-α expression, which in turn activated various subfactors. An upstream effector of glycogen synthase kinase-3β (GSK-3β) inhibited Wnt-10b expression in 3T3-L1 adipocytes. In a previous study of ours, we sequenced the tuna peptide via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and quadrupole time-of-flight mass spectrometry (Q-TOF MS/MS) and confirmed the anti-obesity effects thereof in 3T3-L1 adipocytes. In the present study, we demonstrate that TP-D inhibits C/EBP and promotes Wnt-10b mRNA expression, thus activating the Wnt pathway. The inhibition of lipid accumulation was measured using a glucose and triglyceride (TG) assay. Our results confirmed that TP-D altered the expression levels of C/EBP-related genes in a dose-dependent manner and activated the Wnt signaling pathway. In addition, we confirmed that total adiponectin and high-molecular weight (HMW) adiponectin levels were reduced by treatment with TP-D. These data indicate that TP-D inhibits adipocyte differentiation through the inhibition of C/EBP genes and the subsequent activation of the Wnt/β-catenin signaling pathway.

  5. Black soybean extract improves lipid profiles in fenofibrate-treated type 2 diabetics with postprandial hyperlipidemia.

    Science.gov (United States)

    Kusunoki, Masataka; Sato, Daisuke; Tsutsumi, Kazuhiko; Tsutsui, Hideyo; Nakamura, Takao; Oshida, Yoshiharu

    2015-06-01

    Black soybeans (Glycine max (L.) Merr.) are known to be rich in polyphenols, including anthocyanins, and they have been consumed since ancient times for their beneficial effects on health. In addition, it has been reported that black soybean (BS) seed coat may ameliorate obesity and insulin resistance. In the present study, we administered BS extract to type 2 diabetics for 2 months to investigate the effects of BS on glycemic control and lipid metabolism parameters. In addition, we administered BS and antihyperlipidemic agent, fenofibrate, to patients with type 2 diabetes complicated by postprandial hyperlipidemia for 2 months and assessed the combined effects of fenofibrate and BS on serum lipid profile. The results showed that administration of the BS alone had no effect on the blood glucose or lipid levels, but that administration of fenofibrate alone and fenofibrate in combination with the BS significantly lowered their serum triglyceride (TG) level at fasting state, and the percent decrease in the serum TG level after combined administration was significantly higher than in the subjects who received fenofibrate alone. Furthermore, the serum LDL cholesterol concentration, which did not decrease when fenofibrate was administered alone, decreased significantly when the BS and fenofibrate were administered in combination. These results suggest that combined administration of the BS with fenofibrate enhanced the antihyperlipidemic action of fenofibrate, and the results of this study demonstrated the usefulness of the BS in clinical practice.

  6. Dynamic dissolution-/permeation-testing of nano- and microparticle formulations of fenofibrate

    DEFF Research Database (Denmark)

    Sironi, Daniel; Rosenberg, Jörg; Bauer-Brandl, Annette

    2017-01-01

    The aim of the current study was to evaluate a dynamic dissolution-/permeation-system for prediction of gastrointestinal and absorption-behavior of two commercial fenofibrate formulations. To this end, both dissolution and barrier-flux were followed simultaneously for fenofibrate powder, a microp......The aim of the current study was to evaluate a dynamic dissolution-/permeation-system for prediction of gastrointestinal and absorption-behavior of two commercial fenofibrate formulations. To this end, both dissolution and barrier-flux were followed simultaneously for fenofibrate powder...

  7. Hyperlipidemia-associated pancreatitis in pregnancy managed with fenofibrate.

    Science.gov (United States)

    Whitten, Amy E; Lorenz, Robert P; Smith, Joann M

    2011-02-01

    Pancreatitis is a concerning clinical event during pregnancy, with high morbidity and mortality rates for mother and fetus. Hypertriglyceridemia is considered a rare cause of pancreatitis in pregnancy, with the majority of reported cases being associated with the lipid metabolism disorders. We report on a case of hypertriglyceridemia-induced pancreatitis in a woman presenting at 32 weeks of gestational age. Her dyslipidemia was not controlled with diet alone, necessitating medical intervention. Fenofibrate was used successfully. Recurrence of pancreatitis during the pregnancy was avoided, and a healthy neonate was delivered at 35 weeks of gestation. Fenofibrate was used safely and successfully during pregnancy in this case of hypertriglyceridemia-associated pancreatitis refractory to conservative measures.

  8. The fat controller: adipocyte development.

    Directory of Open Access Journals (Sweden)

    Jacqueline M Stephens

    Full Text Available Obesity is a condition characterized by excess adipose tissue that results from positive energy balance and is the most common metabolic disorder in the industrialized world. The obesity epidemic shows no sign of slowing, and it is increasingly a global problem. Serious clinical problems associated with obesity include an increased risk for type 2 diabetes, atherosclerosis, and cancer. Hence, understanding the origin and development of adipocytes and adipose tissue will be critical to the analysis and treatment of metabolic diseases. Historically, albeit incorrectly, adipocytes were thought to be inert cells whose singular function was lipid storage. It is now known that adipocytes have other critical functions; the most important include sensitivity to insulin and the ability to produce and secrete adipocyte-specific endocrine hormones that regulate energy homeostasis in other tissues. Today, adipocytes are recognized as critical regulators of whole-body metabolism and known to be involved in the pathogenesis of a variety of metabolic diseases. All cells come from other cells and many cells arise from precursor cells. Adipocytes are not created from other adipocytes, but they arise from precursor cells. In the last two decades, scientists have discovered the function of many proteins that influence the ability of precursor cells to become adipocytes. If the expansion of the adipose tissue is the problem, it seems logical that adipocyte development inhibitors could be a viable anti-obesity therapeutic. However, factors that block adipocyte development and limit adipocyte expansion also impair metabolic health. This notion may be counterintuitive, but several lines of evidence support the idea that blocking adipocyte development is unhealthy. For this reason it is clear that we need a better understanding of adipocyte development.

  9. Fenofibrate Induces Ketone Body Production in Melanoma and Glioblastoma Cells

    Science.gov (United States)

    Grabacka, Maja M.; Wilk, Anna; Antonczyk, Anna; Banks, Paula; Walczyk-Tytko, Emilia; Dean, Matthew; Pierzchalska, Malgorzata; Reiss, Krzysztof

    2016-01-01

    Ketone bodies [beta-hydroxybutyrate (bHB) and acetoacetate] are mainly produced in the liver during prolonged fasting or starvation. bHB is a very efficient energy substrate for sustaining ATP production in peripheral tissues; importantly, its consumption is preferred over glucose. However, the majority of malignant cells, particularly cancer cells of neuroectodermal origin such as glioblastoma, are not able to use ketone bodies as a source of energy. Here, we report a novel observation that fenofibrate, a synthetic peroxisome proliferator-activated receptor alpha (PPARa) agonist, induces bHB production in melanoma and glioblastoma cells, as well as in neurospheres composed of non-transformed cells. Unexpectedly, this effect is not dependent on PPARa activity or its expression level. The fenofibrate-induced ketogenesis is accompanied by growth arrest and downregulation of transketolase, but the NADP/NADPH and GSH/GSSG ratios remain unaffected. Our results reveal a new, intriguing aspect of cancer cell biology and highlight the benefits of fenofibrate as a supplement to both canonical and dietary (ketogenic) therapeutic approaches against glioblastoma. PMID:26869992

  10. Theoretical and experimental study of fenofibrate and simvastatin

    Science.gov (United States)

    Nicolás Vázquez, Inés; Rodríguez-Núñez, Jesús Rubén; Peña-Caballero, Vicente; Ruvalcaba, Rene Miranda; Aceves-Hernandez, Juan Manuel

    2017-12-01

    Fenofibrate, an oral fibrate lipid lowering agent, and simvastatin, which reduces plasma levels of low-density lipoprotein cholesterol, are active pharmaceutical ingredients (APIs), currently in the market. We characterized these APIs by thermal analysis and conducted X-ray powder diffraction techniques. Studies should be carried out in the formulation stage before the final composition of a polypill may be established. Thus, it was found in thermochemical studies that both compounds present no chemical interactions in an equimolar mixture of solid samples at room temperature. Theoretical studies were employed to determine possible interactions between fenofibrate and simvastatin. A very weak intramolecular hydrogen bond is formed between the hydroxyl group (O5H5) of the simvastatin with chlorine and carbonyl group (C11O4, C1O2) of the fenofibrate molecule. These weak energy hydrogen bonds have no effect on the chemical stability of the compounds studied. The results were obtained using Density Functional Theory methods; particularly the BPE1BPE and B3LYP functional and 6-31++G** basis set. The values of energy show good approximation when are compared with similar calculations previously reported. Infrared spectra of monomers and dimers were obtained via theoretical calculations.

  11. Fenofibrate induces ketone body production in melanoma and glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Maja M Grabacka

    2016-02-01

    Full Text Available Ketone bodies (beta-hydroxybutyrate, bHB, acetoacetate are mainly produced in the liver during prolonged fasting or starvation. bHB is a very efficient energy substrate for sustaining ATP production in peripheral tissues; importantly its consumption is preferred over glucose. However, the majority of malignant cells, particularly cancer cells of neuroectodermal origin such as glioblastoma, are not able to use ketone bodies as a source of energy. Here, we report a novel observation that fenofibrate, a synthetic peroxisome proliferator-activated receptor alpha (PPARa agonist, induces bHB production in melanoma and glioblastoma cells, as well as in neurospheres composed of nontransformed cells. Unexpectedly, this effect is not dependent on PPARa activity or its expression level. The fenofibrate-induced ketogenesis is accompanied by growth arrest and down-regulation of transketolase, but the NADP/NADPH and GSH/GSSG ratios remain unaffected. Our results reveal a new, intriguing aspect of cancer cell biology and highlight the benefits of fenofibrate as a supplement to both canonical and dietary (ketogenic therapeutic approaches against glioblastoma.

  12. Role of adipocyte-derived lipoprotein lipase in adipocyte hypertrophy

    Directory of Open Access Journals (Sweden)

    Orlando Robert A

    2007-10-01

    Full Text Available Abstract Background A major portion of available fatty acids for adipocyte uptake is derived from lipoprotein lipase (LPL-mediated hydrolysis of circulating lipoprotein particles. In vivo studies aimed at identifying the precise role of adipocyte-derived LPL in fat storage function of adipose tissue have been unable to provide conclusive evidence due to compensatory mechanisms that activate endogenous fatty acid synthesis. To address this gap in knowledge, we have measured the effect of reducing adipocyte LPL expression on intracellular lipid accumulation using a well-established cultured model of adipocyte differentiation. Methods siRNA specific for mouse LPL was transfected into 3T3-L1 adipocytes. Expression of LPL was measured by quantitative real-time PCR and cell surface-associated LPL enzymatic activity was measured by colorimetric detection following substrate (p-nitrophenyl butyrate hydrolysis. Apolipoprotein CII and CIII expression ratios were also measured by qRT-PCR. Intracellular lipid accumulation was quantified by Nile Red staining. Results During differentiation of 3T3-L1 pre-adipocytes, LPL mRNA expression increases 6-fold resulting in a 2-fold increase in cell surface-associated LPL enzymatic activity. Parallel to this increase in LPL expression, we found that intracellular lipids increased ~10-fold demonstrating a direct correlation between adipocyte-derived LPL expression and lipid storage. We next reduced LPL expression in adipocytes using siRNA transfections to directly quantify the contributions of adipocyte-derived LPL to lipid storage, This treatment reduced LPL mRNA expression and cell surface-associated LPL enzymatic activity to ~50% of non-treated controls while intracellular lipid levels were reduced by 80%. Exogenous addition of purified LPL (to restore extracellular lipolytic activity or palmitate (as a source of free fatty acids to siRNA-treated cells restored intracellular lipid levels to those measured for non

  13. Fenofibrate Therapy in Carnitine Palmitoyl Transferase Type 2 Deficiency

    Directory of Open Access Journals (Sweden)

    I. Hamilton-Craig

    2012-01-01

    Full Text Available Bezafibrate therapy has been shown to improve beta-oxidation of fatty acids and to reduce episodes of rhabdomyolysis in patients with carnitine palmitoyltransferase type-2 (CPT2 deficiency. We report the efficacy of fenofibrate in a patient with CPT2 deficiency, in whom beta-oxidation was improved but an episode of rhabdomyolysis nevertheless occurred. This suggests additional methods to avoid rhabdomyolysis in patients with CPT2 deficiency should accompany fibrate therapy, including avoidance of muscular overexertion, dehydration, and heat exposure.

  14. Fenofibrate Therapy Restores Antioxidant Protection and Improves Myocardial Insulin Resistance in a Rat Model of Metabolic Syndrome and Myocardial Ischemia: The Role of Angiotensin II

    Directory of Open Access Journals (Sweden)

    Luz Ibarra-Lara

    2016-12-01

    Full Text Available Renin-angiotensin system (RAS activation promotes oxidative stress which increases the risk of cardiac dysfunction in metabolic syndrome (MetS and favors local insulin resistance. Fibrates regulate RAS improving MetS, type-2 diabetes and cardiovascular diseases. We studied the effect of fenofibrate treatment on the myocardic signaling pathway of Angiotensin II (Ang II/Angiotensin II type 1 receptor (AT1 and its relationship with oxidative stress and myocardial insulin resistance in MetS rats under heart ischemia. Control and MetS rats were assigned to the following groups: (a sham; (b vehicle-treated myocardial infarction (MI (MI-V; and (c fenofibrate-treated myocardial infarction (MI-F. Treatment with fenofibrate significantly reduced triglycerides, non-high density lipoprotein cholesterol (non-HDL-C, insulin levels and insulin resistance index (HOMA-IR in MetS animals. MetS and MI increased Ang II concentration and AT1 expression, favored myocardial oxidative stress (high levels of malondialdehyde, overexpression of nicotinamide adenine dinucleotide phosphate (NADPH oxidase 4 (NOX4, decreased total antioxidant capacity and diminished expression of superoxide dismutase (SOD1, SOD2 and catalase and inhibited expression of the insulin signaling cascade: phosphatidylinositol 3-kinase (PI3K/protein kinase B (PkB, also known as Akt/Glut-4/endothelial nitric oxide synthase (eNOS. In conclusion, fenofibrate treatment favors an antioxidant environment as a consequence of a reduction of the Ang II/AT1/NOX4 signaling pathway, reestablishing the cardiac insulin signaling pathway. This might optimize cardiac metabolism and improve the vasodilator function during myocardial ischemia.

  15. Fenofibrate Intervention and Event Lowering in Diabetes (FIELD study: baseline characteristics and short-term effects of fenofibrate [ISRCTN64783481

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available Abstract Objective The Fenofibrate Intervention and Event Lowering in Diabetes (FIELD Study is examining the effects of long-term fibrate therapy on coronary heart disease (CHD event rates in patients with diabetes mellitus. This article describes the trial's run-in phase and patients' baseline characteristics. Research design and methods FIELD is a double-blind, placebo-controlled trial in 63 centres in 3 countries evaluating the effects of fenofibrate versus placebo on CHD morbidity and mortality in 9795 patients with type 2 diabetes mellitus. Patients were to have no indication for lipid-lowering therapy on randomization, but could start these or other drugs at any time after randomization. Follow-up in the study was to be for a median duration of not less than 5 years and until 500 major coronary events (fatal coronary heart disease plus nonfatal myocardial infarction had occurred. Results About 2100 patients (22% had some manifestation of cardiovascular disease (CVD at baseline and thus high risk status. Less than 25% of patients without CVD had a (UKPDS determined calculated 5-year CHD risk of 30, most were men, two-thirds were aged over 60 years, and substantial proportions had NCEP ATP III features of the metabolic syndrome independent of their diabetes, including low HDL (60%, high blood pressure measurement or treatment for hypertension (84%, high waist measurement (68%, and raised triglycerides (52%. After a 6-week run-in period before randomisation with all participants receiving 200 mg comicronized fenofibrate, there were declines in total and LDL cholesterol (10% and triglycerides (26% and an increase in HDL cholesterol (6.5%. Conclusion The study will show the effect of PPAR-alpha agonist action on CHD and other vascular outcomes in patients with type 2 diabetes including substantial numbers with low to moderate CVD risk but with the various components of the metabolic syndrome. The main results of the study will be reported in

  16. Zfp423 Maintains White Adipocyte Identity through Suppression of the Beige Cell Thermogenic Gene Program.

    Science.gov (United States)

    Shao, Mengle; Ishibashi, Jeff; Kusminski, Christine M; Wang, Qiong A; Hepler, Chelsea; Vishvanath, Lavanya; MacPherson, Karen A; Spurgin, Stephen B; Sun, Kai; Holland, William L; Seale, Patrick; Gupta, Rana K

    2016-06-14

    The transcriptional regulators Ebf2 and Prdm16 establish and maintain the brown and/or beige fat cell identity. However, the mechanisms operating in white adipocytes to suppress the thermogenic gene program and maintain an energy-storing phenotype are less understood. Here, we report that the transcriptional regulator Zfp423 is critical for maintaining white adipocyte identity through suppression of the thermogenic gene program. Zfp423 expression is enriched in white versus brown adipocytes and suppressed upon cold exposure. Doxycycline-inducible inactivation of Zfp423 in mature adipocytes, combined with β-adrenergic stimulation, triggers a conversion of differentiated adiponectin-expressing inguinal and gonadal adipocytes into beige-like adipocytes; this reprogramming event is sufficient to prevent and reverse diet-induced obesity and insulin resistance. Mechanistically, Zfp423 acts in adipocytes to inhibit the activity of Ebf2 and suppress Prdm16 activation. These data identify Zfp423 as a molecular brake on adipocyte thermogenesis and suggest a therapeutic strategy to unlock the thermogenic potential of white adipocytes in obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Fat intake leads to differential response of rat adipocytes to glucose, insulin and ascorbic acid.

    Science.gov (United States)

    Garcia-Diaz, Diego F; Campion, Javier; Arellano, Arianna V; Milagro, Fermin I; Moreno-Aliaga, Maria J; Martinez, J Alfredo

    2012-04-01

    Antioxidant-based treatments have emerged as novel and interesting approaches to counteract fat accumulation in obesity and associated metabolic disturbances. Adipocytes from rats that were fed on chow or high-fat diet (HFD) for 50 d were isolated (primary adipocytes) and incubated (72 h) on low (LG; 5.6 mmol/L) or high (HG; 25 mmol/L) glucose levels, in the presence or absence of 1.6 nmol/L insulin and 200 μmol/L vitamin C (VC). Adipocytes from HFD-fed animals presented lower insulin-induced glucose uptake, lower lactate and glycerol release, and lower insulin-induced secretion of some adipokines as compared with controls. HG treatment restored the blunted response to insulin regarding apelin secretion in adipocytes from HFD-fed rats. VC treatment inhibited the levels of nearly all variables, irrespective of the adipocytes' dietary origin. The HG treatment reduced adipocyte viability, and VC protected from this toxic effect, although more drastically in control adipocytes. Summing up, in vivo chow or HFD intake determines a differential response to insulin and glucose treatments that appears to be dependent on the insulin-resistance status of the adipocytes, while VC modifies some responses from adipocytes independently of the previous dietary intake of the animals.

  18. Fenofibrate Administration Reduces Alcohol and Saccharin Intake in Rats: Possible Effects at Peripheral and Central Levels

    Directory of Open Access Journals (Sweden)

    Mario Rivera-Meza

    2017-07-01

    Full Text Available We have previously shown that the administration of fenofibrate to high-drinker UChB rats markedly reduces voluntary ethanol intake. Fenofibrate is a peroxisome proliferator-activated receptor alpha (PPARα agonist, which induces the proliferation of peroxisomes in the liver, leading to increases in catalase levels that result in acetaldehyde accumulation at aversive levels in the blood when animals consume ethanol. In these new studies, we aimed to investigate if the effect of fenofibrate on ethanol intake is produced exclusively in the liver (increasing catalase and systemic levels of acetaldehyde or there might be additional effects at central level. High drinker rats (UChB were allowed to voluntary drink 10% ethanol for 2 months. Afterward, a daily dose of fenofibrate (25, 50 or 100 mg/kg/day or vehicle (as control was administered orally for 14 days. Voluntary ethanol intake was recorded daily. After that time, animals were deprived of ethanol access for 24 h and administered with an oral dose of ethanol (1 g/kg for acetaldehyde determination in blood. Fenofibrate reduced ethanol voluntary intake by 60%, in chronically drinking rats, at the three doses tested. Acetaldehyde in the blood rose up to between 80 μM and 100 μM. Considering the reduction of ethanol consumption, blood acetaldehyde levels and body weight evolution, the better results were obtained at a dose of 50 mg fenofibrate/kg/day. This dose of fenofibrate also reduced the voluntary intake of 0.2% saccharin by 35% and increased catalase levels 2.5-fold in the liver but showed no effects on catalase levels in the brain. To further study if fenofibrate administration changes the motivational properties of ethanol, a conditioned-place preference experiment was carried out. Animals treated with fenofibrate (50 mg/kg/day did not develop ethanol-conditioned place preference (CPP.In an additional experiment, chronically ethanol-drinking rats underwent two cycles of ethanol

  19. Fenofibrate Administration Reduces Alcohol and Saccharin Intake in Rats: Possible Effects at Peripheral and Central Levels

    Science.gov (United States)

    Rivera-Meza, Mario; Muñoz, Daniel; Jerez, Erik; Quintanilla, María E.; Salinas-Luypaert, Catalina; Fernandez, Katia; Karahanian, Eduardo

    2017-01-01

    We have previously shown that the administration of fenofibrate to high-drinker UChB rats markedly reduces voluntary ethanol intake. Fenofibrate is a peroxisome proliferator-activated receptor alpha (PPARα) agonist, which induces the proliferation of peroxisomes in the liver, leading to increases in catalase levels that result in acetaldehyde accumulation at aversive levels in the blood when animals consume ethanol. In these new studies, we aimed to investigate if the effect of fenofibrate on ethanol intake is produced exclusively in the liver (increasing catalase and systemic levels of acetaldehyde) or there might be additional effects at central level. High drinker rats (UChB) were allowed to voluntary drink 10% ethanol for 2 months. Afterward, a daily dose of fenofibrate (25, 50 or 100 mg/kg/day) or vehicle (as control) was administered orally for 14 days. Voluntary ethanol intake was recorded daily. After that time, animals were deprived of ethanol access for 24 h and administered with an oral dose of ethanol (1 g/kg) for acetaldehyde determination in blood. Fenofibrate reduced ethanol voluntary intake by 60%, in chronically drinking rats, at the three doses tested. Acetaldehyde in the blood rose up to between 80 μM and 100 μM. Considering the reduction of ethanol consumption, blood acetaldehyde levels and body weight evolution, the better results were obtained at a dose of 50 mg fenofibrate/kg/day. This dose of fenofibrate also reduced the voluntary intake of 0.2% saccharin by 35% and increased catalase levels 2.5-fold in the liver but showed no effects on catalase levels in the brain. To further study if fenofibrate administration changes the motivational properties of ethanol, a conditioned-place preference experiment was carried out. Animals treated with fenofibrate (50 mg/kg/day) did not develop ethanol-conditioned place preference (CPP).In an additional experiment, chronically ethanol-drinking rats underwent two cycles of ethanol deprivation

  20. A novel brown adipocyte-enriched long non-coding RNA that is required for brown adipocyte differentiation and sufficient to drive thermogenic gene program in white adipocytes.

    Science.gov (United States)

    Xiong, Yan; Yue, Feng; Jia, Zhihao; Gao, Yun; Jin, Wen; Hu, Keping; Zhang, Yong; Zhu, Dahai; Yang, Gongshe; Kuang, Shihuan

    2018-04-01

    The thermogenic activities of brown and beige adipocytes can be exploited to reduce energy surplus and counteract obesity. Recent RNA sequencing studies have uncovered a number of long noncoding RNAs (lncRNAs) uniquely expressed in white and brown adipose tissues (WAT and BAT), but whether and how these lncRNAs function in adipogenesis remain largely unknown. Here, we report the identification of a novel brown adipocyte-enriched LncRNA (AK079912), and its nuclear localization, function and regulation. The expression of AK079912 increases during brown preadipocyte differentiation and in response to cold-stimulated browning of white adipocytes. Knockdown of AK079912 inhibits brown preadipocyte differentiation, manifested by reductions in lipid accumulation and down-regulation of adipogenic and BAT-specific genes. Conversely, ectopic expression of AK079912 in white preadipocytes up-regulates the expression of genes involved in thermogenesis. Mechanistically, inhibition of AK079912 reduces mitochondrial copy number and protein levels of mitochondria electron transport chain (ETC) complexes, whereas AK079912 overexpression increases the levels of ETC proteins. Lastly, reporter and pharmacological assays identify Pparγ as an upstream regulator of AK079912. These results provide new insights into the function of non-coding RNAs in brown adipogenesis and regulating browning of white adipocytes. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. A Rare Cause of Acute Renal Failure: Fenofibrate-Induced Rhabdomyolysis

    Directory of Open Access Journals (Sweden)

    Ferhat Icme

    2013-08-01

    Full Text Available Fibrates are derivative of fibric acid and broad spectrum drugs which are commonly used in the treatment of dyslipidemia and hypertriglyceridemia. Side effects are often related with striated muscles, kidney and liver. Rhabdomyolysis developing with striated muscle destruction is potentially the most lethal of these side effects. Although several case reports of rhabdomyolysis have been reported due to the combination of statin and fenofibrate, fenofibrate alone rarely causes rhabdomyolysis. The purposes of this paper are to present a patient whom we diagnosed with acute renal injury due to use of fenofibrate in order to emphasize the importance of questioning drugs which have been used, and to review management of rhabdomyolysis due to fenofibrate use. [Cukurova Med J 2013; 38(4.000: 800-804

  2. Effects of Fenofibrate on Adiponectin Expression in Retinas of Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Ying-Jung Hsu

    2014-01-01

    Full Text Available Adiponectin has been associated with increased risks of microvascular complications in diabetes; however, its role in the development of diabetic retinopathy (DR is unknown. Fenofibrate is a lipid-lowering agent that has been shown to be capable of preventing DR progression. We investigated the expression of adiponectin and its receptors in DR and evaluated the effects of fenofibrate on their expression. The mRNA and protein levels of adiponectin and its receptors were elevated in retinas of streptozotocin-induced diabetic rats and were suppressed following fenofibrate treatment. Immunofluorescence staining demonstrated that adiponectin and adipoR1 were expressed in cells located within blood vessels, the retinal ganglion, and the inner nuclear layer. AdipoR1 was strongly expressed whereas adipoR2 was only weekly expressed in vascular endothelial cells. The in vitro experiments showed that adiponectin expression was induced by high glucose concentrations in RGC-5 and RAW264.7 cells and was suppressed following fenofibrate treatment. AdipoR1 and adipoR2 levels in RGC-5 cells were elevated in high glucose concentrations and suppressed by fenofibrate. Our results demonstrated that adiponectin may be a proinflammatory mediator in diabetic retinas and fenofibrate appears to modulate the expression of adiponectin and its receptors in diabetic retinas, effectively reducing DR progression.

  3. [Fibrates therapy: Rational use fenofibrate 2016. Executive summary].

    Science.gov (United States)

    Brea, Angel; Millán, Jesús; Ascaso, Juan F; Blasco, Mariano; Díaz, Angel; González-Santos, Pedro; Hernández-Mijares, Antonio; Mantilla, Teresa; Pedro-Botet, Juan C; Pintó, Xavier

    To control lipid factors risk, beyond proper management of LDL cholesterol according to individual risk, detection and treatment of atherogenic dyslipidemia and abnormal levels of triglycerides or HDL cholesterol it should be considered for address a global cardiovascular protection, both in primary and secondary prevention. In this sense, these recommendations collect data on efficacy and safety about the combination statin with fibrates, often necessary for total control of dyslipidemia, particularly in patients with metabolic disorders such as diabetes mellitus, metabolic syndrome or visceral obesity. Reference to control and monitoring of treatment is also done, as well as benefits of fenofibrate not linked directly to their lipid-lowering effect. Copyright © 2016 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Spray drying of fenofibrate loaded nanostructured lipid carriers

    DEFF Research Database (Denmark)

    Xia, Dengning; Shrestha, Neha; van de Streek, Jacco

    2016-01-01

    The conversion of aqueous dispersion of nanostructured lipid carriers (NLCs) into dry powder by spray drying could be a useful approach to render NLCs with better physical chemical stability than the aqueous dispersion. In this study, aqueous NLC dispersion containing fenofibrate was converted...... into dry, easily reconstitutable powder using spray drying. A central composite face centered design (CCFD) was used to investigate the influence of the ratio of lipid to protectant (mannitol and trehalose) and crystallinity of spray-dried powder on the particle size, yield and residual moisture content...... of the dried powder. A linear relationship (R2 = 0.9915) was established between the crystalline content of the spray-dried powders against the ratio of mannitol to trehalose from 3:7 to 10:0 (w/w). Spray drying of NLC aqueous dispersion using a mannitol and trehalose mixture resulted in an increase...

  5. [The significance of fenofibrate in the therapy of atherogenic dyslipoproteinaemia].

    Science.gov (United States)

    Kucera, M; Oravec, S; Ocadlík, I

    2010-08-01

    There are accepted the lipid levels goals in all world, which are needed to achievement in primary and secondary prevention. Despite efficacy of current standards of care (including achievement of LDL-C, blood pressure and blood sugar goals), patients with atherogenic dyslipidemia (DLP) (high TG levels, low HDL-C, high apolipoprotein B and small dense LDL-particles), which is common in patients with diabetes melitus (DM), metabolic syndrome or cardiovascular diseases (KVD), remain exposed to a high residual risk of major cardiovascular events and microvascular complications. Statin therapy does not adequately address vascular risk asociated with elevated triglycerides (TG) and low HDL-C levels. As ACCORD lipid trial last time shows, the addition of lipid-modifying activity of fenofibrate to statin therapy benefited only certain subgroups of patients at increased cardiometabolic risk.

  6. Phenolic compounds apigenin, hesperidin and kaempferol reduce in vitro lipid accumulation in human adipocytes.

    Science.gov (United States)

    Gómez-Zorita, Saioa; Lasa, Arrate; Abendaño, Naiara; Fernández-Quintela, Alfredo; Mosqueda-Solís, Andrea; Garcia-Sobreviela, Maria Pilar; Arbonés-Mainar, Jose M; Portillo, Maria P

    2017-11-21

    Adipocytes derived from human mesenchymal stem cells (MSCs) are widely used to investigate adipogenesis. Taking into account both the novelty of these MSCs and the scarcity of studies focused on the effects of phenolic compounds, the aim of the present study was to analyze the effect of apigenin, hesperidin and kaempferol on pre-adipocyte and mature adipocytes derived from this type of cells. In addition, the expression of genes involved in TG accumulation was also measured. Pre-adipocytes were cultured from day 0 to day 8 and mature adipocytes for 48 h with the polyphenols at doses of 1, 10 and 25 µM. Apigenin did not show an anti-adipogenic action. Pre-adipocytes treated with hesperidin and kaempferol showed reduced TG content at the three experimental doses. Apigenin did not modify the expression of the main adipogenic genes (c/ebpβ, c/ebpα, pparγ and srebp1c), hesperidin inhibited genes involved in the three phases of adipogenesis (c/ebpβ, srebp1c and perilipin) and kaempferol reduced c/ebpβ. In mature adipocytes, the three polyphenols reduced TG accumulation at the dose of 25 µM, but not at lower doses. All compounds increased mRNA levels of atgl. Apigenin and hesperidin decreased fasn expression. The present study shows the anti-adipogenic effect and delipidating effects of apigenin, hesperidin and kaempferol in human adipocytes derived from hMSCs. While hesperidin blocks all the stages of adipogenesis, kaempferol only inhibits the early stage. Regarding mature adipocytes, the three compounds reduce TG accumulation by activating, at least in part, lipolysis, and in the case of hesperidin and apigenin, also by reducing lipogenesis. The present study shows for the first time the anti-adipogenic effect and delipidating effect of apigenin, hesperidin and kaempferol in human adipocytes derived from MSCs for the first time.

  7. Methylation of miR-145a-5p promoter mediates adipocytes differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Du, Jingjing; Cheng, Xiao; Shen, Linyuan; Tan, Zhendong; Luo, Jia; Wu, Xiaoqian; Liu, Chendong [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Yang, Qiong [Department of Animal Husbandry and Veterinary Medicine, Chengdu Agricultural College, Chengdu 611100, Sichuan (China); Jiang, Yanzhi [College of Life and Science, Sichuan Agricultural University, Chengdu 611130 (China); Tang, Guoqing; Li, Xuewei [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Zhang, Shunhua, E-mail: zhangsh1919@163.com [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China); Zhu, Li, E-mail: zhuli7508@163.com [College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130 (China)

    2016-06-17

    MicroRNAs (miRNAs, miR) play important roles in adipocyte development. Recent studies showed that the expression of several miRNAs is closely related with promoter methylation. However, it is not known whether miRNA mediates adipocytes differentiation by means of DNA methylation. Here, we showed that miR-145a-5p was poorly expressed in adipose tissue from mice fed a high fat diet (HFD). Overexpression or inhibition of miR-145a-5p was unfavorable or beneficial, respectively, for adipogenesis, and these effects were achieved by regulating adipocyte-specific genes involved in lipogenic transcription, fatty acid synthesis, and fatty acid transportation. Particularly, we first suggested that miR-145a-5p mimics or inhibitors promoted or repressed adipocytes proliferation by regulating p53 and p21, which act as cell cycle regulating factors. Surprisingly, the miR-145a-5p-repressed adipocyte differentiation was enhanced or rescued when cells treated with 5-Aza-dC were transfected with miR-145a-5p mimics or inhibitors, respectively. These data indicated that, as a new mean to positively regulate adipocyte proliferation, the process of miR-145a-5p-inhibited adipogenesis may be regulated by DNA methylation. -- Highlights: •MiR-145a-5p promotes adipocytes proliferation. •MiR-145a-5p is negatively correlated with obesity. •MiR-145a-5p mediates adipocytes differentiation via regulating pathway related adipocytes differentiation. MiR-145a-5p mediating adipocytes differentiation was regulated by DNA methylation.

  8. Effects of Kurozu concentrated liquid on adipocyte size in rats

    Directory of Open Access Journals (Sweden)

    Nakamura Kumi

    2010-11-01

    Full Text Available Abstract Background Kurozu concentrated liquid (KCL is used as a health-promoting supplement for the treatment of disorders such as cancer, hyperlipidemia, and hypertension in Japan. We investigated the possible anti-obesity effects of KCL in rats. Methods Male Sprague Dawley rats were fed American Institute of Nutrition 76 formula diet and were orally administrated KCL or acetic acid at a dose of 100 mg/kg body weight or deionized water for 4 weeks. Adipocyte size, DNA content in subcutaneous adipose tissue, lipid levels in the serum and liver, and the rate of fatty acid excretion were determined. Effects of KCL on pancreatic lipase activity and 3T3-L1 preadipocyte differentiation were investigated in vitro. Results In the KCL group, the average adipocyte size in subcutaneous and perirenal adipose tissues was significantly reduced. The KCL-administered rats displayed greater numbers of small adipocytes in the subcutaneous, perirenal and mesenteric adipose tissues than did rats from the other groups. In the KCL group, the DNA content in subcutaneous adipose tissue was significantly increased. The rate of fatty acid excretion was significantly increased in the KCL group. Furthermore, KCL significantly inhibited pancreatic lipase activity in vitro, and also significantly inhibited fat accumulation and mRNA expression of fatty acid binding protein 2 (aP2 and peroxisome proliferator-activated γ (PPARγ in 3T3-L1 preadipocyte. The levels of serum and liver lipids, the concentration of serum glucose, and the levels of adiponectin were similar among the 3 groups. Conclusion Oral administration of KCL decreases the adipocyte size via inhibition of dietary fat absorption and reductions of PPARγ and aP2 mRNA expression levels in adipocytes.

  9. Inhibitory effect of leptin on rosiglitazone-induced differentiation of primary adipocytes prepared from TallyHO/Jng mice

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Young; Kim, Joo Young; Sung, Yoon-Young; Jung, Won Hoon; Kim, Hee-Youn; Park, Ji Seon; Cheon, Hyae Gyeong [Medicinal Science Division, Korea Research Institute of Chemical Technology, 100 Jang-dong, Yuseong, 305-600 Daejon (Korea, Republic of); Rhee, Sang Dal, E-mail: sdrhee@krict.re.kr [Medicinal Science Division, Korea Research Institute of Chemical Technology, 100 Jang-dong, Yuseong, 305-600 Daejon (Korea, Republic of)

    2011-03-25

    Research highlights: {yields} In this study, we investigated the effects of leptin on adipocyte differentiation prepared from subcutaneous fat of TallyHo mice. {yields} Leptin inhibited the adipocytes differentiation at physiological concentration via inhibition of PPAR{gamma} expression. {yields} Inhibitors of ERK and STAT1 restored the leptin's inhibitory activity both in vitro and in vivo. -- Abstract: The effects of leptin on rosiglitazone-induced adipocyte differentiation were investigated in the primary adipocytes prepared from subcutaneous fat of TallyHO/Jng (TallyHO) mouse, a recently developed model animal for type 2 diabetes mellitus (T2DM). The treatment of leptin inhibited the rosiglitazone-induced adipocyte differentiation with a decreased expression of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) a key adipogenic transcription factor, both in mRNA and protein levels. Leptin (10 nM) was sufficient to inhibit the adipocyte differentiation, which seemed to come from increased expression of leptin receptor genes in the fat of TallyHO mice. The inhibition of adipogenesis by leptin was restored by the treatment of inhibitors for extracellular-signal-regulated kinase (ERK) (PD98059) and signal transducer and activator of transcription-1 (STAT1) (fludarabine). Furthermore, in vivo intraperitoneal administration of PD98059 and fludarabine increased the PPAR{gamma} expression in the subcutaneous fat of TallyHO mice. These data suggest that leptin could inhibit the PPAR{gamma} expression and adipocyte differentiation in its physiological concentration in TallyHO mice.

  10. Rationale for an adjunctive therapy with fenofibrate in pharmacoresistant nocturnal frontal lobe epilepsy.

    Science.gov (United States)

    Puligheddu, Monica; Melis, Miriam; Pillolla, Giuliano; Milioli, Giulia; Parrino, Liborio; Terzano, Giovanni Mario; Aroni, Sonia; Sagheddu, Claudia; Marrosu, Francesco; Pistis, Marco; Muntoni, Anna Lisa

    2017-10-01

    Nocturnal frontal lobe epilepsy (NFLE) is an idiopathic partial epilepsy with a family history in about 25% of cases, with autosomal dominant inheritance (autosomal dominant NFLE [ADNFLE]). Traditional antiepileptic drugs are effective in about 55% of patients, whereas the rest remains refractory. One of the key pathogenetic mechanisms is a gain of function of neuronal nicotinic acetylcholine receptors (nAChRs) containing the mutated α4 or β2 subunits. Fenofibrate, a common lipid-regulating drug, is an agonist at peroxisome proliferator-activated receptor alpha (PPARα) that is a ligand-activated transcription factor, which negatively modulates the function of β2-containing nAChR. To test clinical efficacy of adjunctive therapy with fenofibrate in pharmacoresistant ADNFLE\\NFLE patients, we first demonstrated the effectiveness of fenofibrate in a mutated mouse model displaying both disease genotype and phenotype. We first tested the efficacy of fenofibrate in transgenic mice carrying the mutation in the α4-nAChR subunit (Chrna4S252F) homologous to that found in humans. Subsequently, an add-on protocol was implemented in a clinical setting and fenofibrate was administered to pharmacoresistant NFLE patients. Here, we show that a chronic fenofibrate diet markedly reduced the frequency of large inhibitory postsynaptic currents (IPSCs) recorded from cortical pyramidal neurons in Chrna4S252F mice, and prevented nicotine-induced increase of IPSC frequency. Moreover, fenofibrate abolished differences between genotypes in the frequency of sleep-related movements observed under basal conditions. Patients affected by NFLE, nonresponders to traditional therapy, by means of adjunctive therapy with fenofibrate displayed a reduction of seizure frequency. Furthermore, digital video-polysomnographic recordings acquired in NFLE subjects after 6 months of adjunctive fenofibrate substantiated the significant effects on control of motor-behavioral seizures. Our preclinical and

  11. Kolliphor surfactants affect solubilization and bioavailability of fenofibrate. Studies of in vitro digestion and absorption in rats

    DEFF Research Database (Denmark)

    Berthelsen, Ragna; Holm, Rene; Jacobsen, Jette

    2015-01-01

    formulations only comprised an aqueous micellar solution of the model drug (fenofibrate) in varying concentrations (2–25% (w/v)) of the three tested surfactants. Increased concentrations of Kolliphor ELP and EL led to increased fenofibrate AUC0–24h values. For the Kolliphor RH40 formulations, an apparent...... fenofibrate absorption optimum was seen at 15% (w/v) surfactant, displaying both the highest AUC0–24h and Cmax. The reduced absorption of fenofibrate from the formulation containing the highest level of surfactant (25% w/v) was thought to be caused by some degree of trapping within Kolliphor RH40 micelles....... In vitro, Kolliphor ELP and EL were found to be more prone to digestion than Kolliphor RH40, though not affecting the in vivo results. The highest fenofibrate bioavailability was attained from formulations with high Kolliphor ELP/EL levels (25% (w/v)), indicating that these surfactants are the better...

  12. Relationships between cell surface insulin binding and endocytosis in adipocytes

    International Nuclear Information System (INIS)

    Jochen, A.L.

    1988-01-01

    Chymotrypsin substrate analogues, such as N-acetyl-Tyr ethyl ester, have recently been demonstrated to inhibit the endocytic uptake of insulin in isolated rat adipocytes. In this study, the effect of N-acetyl-Tyr ethyl ester on cell surface insulin binding and dissociation were examined. Surface-bound 125 I-insulin was distinguished from intracellular 125 I-insulin by the sensitivity of the former to rapid dissociation with an acidic buffer. Plateau levels of surface-bound insulin at 37 degree C were increased 70% by inhibiting the internalization pathway. This increase was temperature and insulin concentration dependent. Thus differences in surface binding were small at 12 degree C and also at high insulin concentrations. Inhibition of internalization with N-acetyl-Tyr ethyl ester markedly slowed the loss of surface-bound insulin observed during dissociation the loss of surface-bound insulin observed during dissociation studies. After 20-30 min of dissociation, the remaining levels of surface-bound insulin were three- to fourfold higher in treated adipocytes compared with control adipocytes. Added unlabeled insulin retained its ability to accelerate the dissociation of insulin in N-acetyl-Tyr ethyl ester-treated cells. These observations indicate that the internalization pathway is a quantitatively important factor in determining levels of surface binding at 37 degree C and in determining the rat of deactivation of insulin binding

  13. Implication of the Tpl2 kinase in inflammatory changes and insulin resistance induced by the interaction between adipocytes and macrophages.

    Science.gov (United States)

    Ceppo, Franck; Berthou, Flavien; Jager, Jennifer; Dumas, Karine; Cormont, Mireille; Tanti, Jean-François

    2014-03-01

    Adipose tissue inflammation is associated with the development of insulin resistance. In obese adipose tissue, lipopolysaccharides (LPSs) and saturated fatty acids trigger inflammatory factors that mediate a paracrine loop between adipocytes and macrophages. However, the inflammatory signaling proteins underlying this cross talk remain to be identified. The mitogen-activated protein kinase kinase kinase tumor progression locus 2 (Tpl2) is activated by inflammatory stimuli, including LPS, and its expression is up-regulated in obese adipose tissue, but its role in the interaction between adipocytes and macrophages remains ill-defined. To assess the implication of Tpl2 in the cross talk between these 2 cell types, we used coculture system and conditioned medium (CM) from macrophages. Pharmacological inhibition of Tpl2 in the coculture markedly reduced lipolysis and cytokine production and prevented the decrease in adipocyte insulin signaling. Tpl2 knockdown in cocultured adipocytes reduced lipolysis but had a weak effect on cytokine production and did not prevent the alteration of insulin signaling. By contrast, Tpl2 silencing in cocultured macrophages resulted in a marked inhibition of cytokine production and prevented the alteration of adipocyte insulin signaling. Further, when Tpl2 was inhibited in LPS-activated macrophages, the produced CM did not alter adipocyte insulin signaling and did not induce an inflammatory response in adipocytes. By contrast, Tpl2 silencing in adipocytes did not prevent the deleterious effects of a CM from LPS-activated macrophages. Together, these data establish that Tpl2, mainly in macrophages, is involved in the cross talk between adipocytes and macrophages that promotes inflammatory changes and alteration of insulin signaling in adipocytes.

  14. Bone marrow adipocytes promote the regeneration of stem cells and haematopoiesis by secreting SCF.

    Science.gov (United States)

    Zhou, Bo O; Yu, Hua; Yue, Rui; Zhao, Zhiyu; Rios, Jonathan J; Naveiras, Olaia; Morrison, Sean J

    2017-08-01

    Endothelial cells and leptin receptor + (LepR + ) stromal cells are critical sources of haematopoietic stem cell (HSC) niche factors, including stem cell factor (SCF), in bone marrow. After irradiation or chemotherapy, these cells are depleted while adipocytes become abundant. We discovered that bone marrow adipocytes synthesize SCF. They arise from Adipoq-Cre/ER + progenitors, which represent ∼5% of LepR + cells, and proliferate after irradiation. Scf deletion using Adipoq-Cre/ER inhibited haematopoietic regeneration after irradiation or 5-fluorouracil treatment, depleting HSCs and reducing mouse survival. Scf from LepR + cells, but not endothelial, haematopoietic or osteoblastic cells, also promoted regeneration. In non-irradiated mice, Scf deletion using Adipoq-Cre/ER did not affect HSC frequency in long bones, which have few adipocytes, but depleted HSCs in tail vertebrae, which have abundant adipocytes. A-ZIP/F1 'fatless' mice exhibited delayed haematopoietic regeneration in long bones but not in tail vertebrae, where adipocytes inhibited vascularization. Adipocytes are a niche component that promotes haematopoietic regeneration.

  15. Proteasome Dysfunction Associated to Oxidative Stress and Proteotoxicity in Adipocytes Compromises Insulin Sensitivity in Human Obesity

    Science.gov (United States)

    Díaz-Ruiz, Alberto; Guzmán-Ruiz, Rocío; Moreno, Natalia R.; García-Rios, Antonio; Delgado-Casado, Nieves; Membrives, Antonio; Túnez, Isaac; El Bekay, Rajaa; Fernández-Real, José M.; Tovar, Sulay; Diéguez, Carlos; Tinahones, Francisco J.; Vázquez-Martínez, Rafael; López-Miranda, José

    2015-01-01

    Abstract Aims: Obesity is characterized by a low-grade systemic inflammatory state and adipose tissue (AT) dysfunction, which predispose individuals to the development of insulin resistance (IR) and metabolic disease. However, a subset of obese individuals, referred to as metabolically healthy obese (MHO) individuals, are protected from obesity-associated metabolic abnormalities. Here, we aim at identifying molecular factors and pathways in adipocytes that are responsible for the progression from the insulin-sensitive to the insulin-resistant, metabolically unhealthy obese (MUHO) phenotype. Results: Proteomic analysis of paired samples of adipocytes from subcutaneous (SC) and omental (OM) human AT revealed that both types of cells are altered in the MUHO state. Specifically, the glutathione redox cycle and other antioxidant defense systems as well as the protein-folding machinery were dysregulated and endoplasmic reticulum stress was increased in adipocytes from IR subjects. Moreover, proteasome activity was also compromised in adipocytes of MUHO individuals, which was associated with enhanced accumulation of oxidized and ubiquitinated proteins in these cells. Proteasome activity was also impaired in adipocytes of diet-induced obese mice and in 3T3-L1 adipocytes exposed to palmitate. In line with these data, proteasome inhibition significantly impaired insulin signaling in 3T3-L1 adipocytes. Innovation: This study provides the first evidence of the occurrence of protein homeostasis deregulation in adipocytes in human obesity, which, together with oxidative damage, interferes with insulin signaling in these cells. Conclusion: Our results suggest that proteasomal dysfunction and impaired proteostasis in adipocytes, resulting from protein oxidation and/or misfolding, constitute major pathogenic mechanisms in the development of IR in obesity. Antioxid. Redox Signal. 23, 597–612. PMID:25714483

  16. Cellular spelunking: exploring adipocyte caveolae.

    Science.gov (United States)

    Pilch, Paul F; Souto, Ricardo P; Liu, Libin; Jedrychowski, Mark P; Berg, Eric A; Costello, Catherine E; Gygi, Steven P

    2007-10-01

    It has been known for decades that the adipocyte cell surface is particularly rich in small invaginations we now know to be caveolae. These structures are common to many cell types but are not ubiquitous. They have generated considerable curiosity, as manifested by the numerous publications on the topic that describe various, sometimes contradictory, caveolae functions. Here, we review the field from an "adipocentric" point of view and suggest that caveolae may have a function of particular use for the fat cell, namely the modulation of fatty acid flux across the plasma membrane. Other functions for adipocyte caveolae that have been postulated include participation in signal transduction and membrane trafficking pathways, and it will require further experimental scrutiny to resolve controversies surrounding these possible activities.

  17. Suppressive Role of PPARγ-Regulated Endothelial Nitric Oxide Synthase in Adipocyte Lipolysis.

    Directory of Open Access Journals (Sweden)

    Yoko Yamada

    Full Text Available Metabolic syndrome causes insulin resistance and is associated with risk factor clustering, thereby increasing the risk of atherosclerosis. Recently, endothelial nitric oxide synthase deficient (eNOS-/- mice have been reported to show metabolic disorders. Interestingly, eNOS has also been reported to be expressed in non-endothelial cells including adipocytes, but the functions of eNOS in adipocytes remain unclear.The eNOS expression was induced with adipocyte differentiation and inhibition of eNOS/NO enhanced lipolysis in vitro and in vivo. Furthermore, the administration of a high fat diet (HFD was able to induce non-alcoholic steatohepatitis (NASH in eNOS-/- mice but not in wild type mice. A PPARγ antagonist increased eNOS expression in adipocytes and suppressed HFD-induced fatty liver changes.eNOS-/- mice induce NASH development, and these findings provide new insights into the therapeutic approach for fatty liver disease and related disorders.

  18. Stress of endoplasmic reticulum modulates differentiation and lipogenesis of human adipocytes

    International Nuclear Information System (INIS)

    Koc, Michal; Mayerová, Veronika; Kračmerová, Jana; Mairal, Aline; Mališová, Lucia; Štich, Vladimír; Langin, Dominique; Rossmeislová, Lenka

    2015-01-01

    Background: Adipocytes are cells specialized for storage of neutral lipids. This storage capacity is dependent on lipogenesis and is diminished in obesity. The reason for the decline in lipogenic activity of adipocytes in obesity remains unknown. Recent data show that lipogenesis in liver is regulated by pathways initiated by endoplasmic reticulum stress (ERS). Thus, we aimed at investigating the effect of ERS on lipogenesis in adipose cells. Methods: Preadipocytes were isolated from subcutaneous abdominal adipose tissue from obese volunteers and in vitro differentiated into adipocytes. ERS was induced pharmacologically by thapsigargin (TG) or tunicamycin (TM). Activation of Unfolded Protein Response pathway (UPR) was monitored on the level of eIF2α phosphorylation and mRNA expression of downstream targets of UPR sensors. Adipogenic and lipogenic capacity was evaluated by Oil Red O staining, measurement of incorporation of radio-labelled glucose or acetic acid into lipids and mRNA analysis of adipogenic/lipogenic markers. Results: Exposition of adipocytes to high doses of TG (100 nM) and TM (1 μg/ml) for 1–24 h enhanced expression of several UPR markers (HSPA5, EDEM1, ATF4, XBP1s) and phosphorylation of eIF2α. This acute ERS substantially inhibited expression of lipogenic genes (DGAT2, FASN, SCD1) and glucose incorporation into lipids. Moreover, chronic exposure of preadipocytes to low dose of TG (2.5 nM) during the early phases of adipogenic conversion of preadipocytes impaired both, lipogenesis and adipogenesis. On the other hand, chronic low ERS had no apparent effect on lipogenesis in mature adipocytes. Conclusions: Acute ERS weakened a capacity of mature adipocytes to store lipids and chronic ERS diminished adipogenic potential of preadipocytes. - Highlights: • High intensity ERS inhibits lipogenic capacity of adipocytes. • ERS impairs adipogenesis when present in early stages of adipogenesis. • Lipogenesis in mature adipocytes is not

  19. Stress of endoplasmic reticulum modulates differentiation and lipogenesis of human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Koc, Michal; Mayerová, Veronika; Kračmerová, Jana [Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague (Czech Republic); Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, CZ-100 00 (Czech Republic); Mairal, Aline [Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague (Czech Republic); Inserm, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, 31432 Toulouse, Cedex 4 (France); Mališová, Lucia; Štich, Vladimír [Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague (Czech Republic); Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, CZ-100 00 (Czech Republic); Langin, Dominique [Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague (Czech Republic); Inserm, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, 31432 Toulouse, Cedex 4 (France); University of Toulouse, UMR1048, Paul Sabatier University, 31432 Toulouse, Cedex 4 (France); Toulouse University Hospitals, Department of Clinical Biochemistry, 31059 Toulouse, Cedex 9 (France); Rossmeislová, Lenka, E-mail: Lenka.Rossmeislova@lf3.cuni.cz [Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague (Czech Republic); Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, CZ-100 00 (Czech Republic)

    2015-05-08

    Background: Adipocytes are cells specialized for storage of neutral lipids. This storage capacity is dependent on lipogenesis and is diminished in obesity. The reason for the decline in lipogenic activity of adipocytes in obesity remains unknown. Recent data show that lipogenesis in liver is regulated by pathways initiated by endoplasmic reticulum stress (ERS). Thus, we aimed at investigating the effect of ERS on lipogenesis in adipose cells. Methods: Preadipocytes were isolated from subcutaneous abdominal adipose tissue from obese volunteers and in vitro differentiated into adipocytes. ERS was induced pharmacologically by thapsigargin (TG) or tunicamycin (TM). Activation of Unfolded Protein Response pathway (UPR) was monitored on the level of eIF2α phosphorylation and mRNA expression of downstream targets of UPR sensors. Adipogenic and lipogenic capacity was evaluated by Oil Red O staining, measurement of incorporation of radio-labelled glucose or acetic acid into lipids and mRNA analysis of adipogenic/lipogenic markers. Results: Exposition of adipocytes to high doses of TG (100 nM) and TM (1 μg/ml) for 1–24 h enhanced expression of several UPR markers (HSPA5, EDEM1, ATF4, XBP1s) and phosphorylation of eIF2α. This acute ERS substantially inhibited expression of lipogenic genes (DGAT2, FASN, SCD1) and glucose incorporation into lipids. Moreover, chronic exposure of preadipocytes to low dose of TG (2.5 nM) during the early phases of adipogenic conversion of preadipocytes impaired both, lipogenesis and adipogenesis. On the other hand, chronic low ERS had no apparent effect on lipogenesis in mature adipocytes. Conclusions: Acute ERS weakened a capacity of mature adipocytes to store lipids and chronic ERS diminished adipogenic potential of preadipocytes. - Highlights: • High intensity ERS inhibits lipogenic capacity of adipocytes. • ERS impairs adipogenesis when present in early stages of adipogenesis. • Lipogenesis in mature adipocytes is not

  20. UCP1 induction during recruitment of brown adipocytes in white adipose tissue is dependent on cyclooxygenase activity

    DEFF Research Database (Denmark)

    Madsen, Lise; Pedersen, Lone M; Lillefosse, Haldis Haukaas

    2010-01-01

    BACKGROUND: The uncoupling protein 1 (UCP1) is a hallmark of brown adipocytes and pivotal for cold- and diet-induced thermogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that cyclooxygenase (COX) activity and prostaglandin E(2) (PGE(2)) are crucially involved in induction of UCP1...... expression in inguinal white adipocytes, but not in classic interscapular brown adipocytes. Cold-induced expression of UCP1 in inguinal white adipocytes was repressed in COX2 knockout (KO) mice and by administration of the COX inhibitor indomethacin in wild-type mice. Indomethacin repressed beta......-adrenergic induction of UCP1 expression in primary inguinal adipocytes. The use of PGE(2) receptor antagonists implicated EP(4) as a main PGE(2) receptor, and injection of the stable PGE(2) analog (EP(3/4) agonist) 16,16 dm PGE(2) induced UCP1 expression in inguinal white adipose tissue. Inhibition of COX activity...

  1. Enhancement of the dissolution rate and bioavailability of fenofibrate by a melt-adsorption method using supercritical carbon dioxide

    Directory of Open Access Journals (Sweden)

    Cha KH

    2012-10-01

    Full Text Available Kwang-Ho Cha,1,3 Kyung-Jin Cho,3 Min-Soo Kim,4 Jeong-Soo Kim,3 Hee Jun Park,1,3 Junsung Park,1,3 Wonkyung Cho,1,3 Jeong-Sook Park,3 Sung-Joo Hwang1,21Yonsei Institute of Pharmaceutical Sciences, 2College of Pharmacy, Yonsei University, Incheon, Republic of Korea; 3College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea; 4Department of Pharmaceutical Engineering, Inje University, Gimhae, Republic of KoreaBackground: The aim of this study was to enhance the bioavailability of fenofibrate, a poorly water-soluble drug, using a melt-adsorption method with supercritical CO2.Methods: Fenofibrate was loaded onto Neusilin® UFL2 at different weight ratios of fenofibrate to Neusilin UFL2 by melt-adsorption using supercritical CO2. For comparison, fenofibrate-loaded Neusilin UFL2 was prepared by solvent evaporation and hot melt-adsorption methods. The fenofibrate formulations prepared were characterized by differential scanning calorimetry, powder x-ray diffractometry, specific surface area, pore size distribution, scanning electron microscopy, and energy-dispersive x-ray spectrometry. In vitro dissolution and in vivo bioavailability were also investigated.Results: Fenofibrate was distributed into the pores of Neusilin UFL2 and showed reduced crystal formation following adsorption. Supercritical CO2 facilitated the introduction of fenofibrate into the pores of Neusilin UFL2. Compared with raw fenofibrate, fenofibrate from the prepared powders showed a significantly increased dissolution rate and better bioavailability. In particular, the area under the drug concentration-time curve and maximal serum concentration of the powders prepared using supercritical CO2 were 4.62-fold and 4.52-fold greater than the corresponding values for raw fenofibrate.Conclusion: The results of this study highlight the usefulness of the melt-adsorption method using supercritical CO2 for improving the bioavailability of fenofibrate.Keywords: fenofibrate

  2. Comparative transcriptomic and metabolomic analysis of fenofibrate and fish oil treatments in mice

    NARCIS (Netherlands)

    Lu, Y.; Boekschoten, M.V.; Wopereis, S.; Müller, M.; Kersten, S.

    2011-01-01

    Comparative transcriptomic and metabolomic analysis of fenofibrate and fish oil treatments in mice. Physiol Genomics 43: 1307-1318, 2011. First published September 27, 2011; doi:10.1152/physiolgenomics.00100.2011. Elevated circulating triglycerides, which are considered a risk factor for

  3. Hepatotoxic effects of fenofibrate in spontaneously hypertensive rats expressing human C-reactive protein

    Czech Academy of Sciences Publication Activity Database

    Škop, V.; Trnovská, J.; Oliyarnyk, O.; Marková, I.; Malínská, H.; Kazdová, L.; Zídek, Václav; Landa, Vladimír; Mlejnek, Petr; Šimáková, Miroslava; Kůdela, M.; Pravenec, Michal; Šilhavý, Jan

    2016-01-01

    Roč. 65, č. 6 (2016), s. 891-899 ISSN 0862-8408 R&D Projects: GA MZd(CZ) NT14325 Institutional support: RVO:67985823 Keywords : fenofibrate * rosuvastatin * C-reactive protein * transgenic * spontaneously hypertensive rat * inflammation * hepatotoxic Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.461, year: 2016

  4. Fenofibrate and rosiglitazone improve quality of lipoproteins in patients with type 2 diabetes mellitus

    Czech Academy of Sciences Publication Activity Database

    Vrablík, M.; Dobiášová, Milada; Štulc, T.; Kasalová, Z.; Doležalová, R.; Prázný, M.; Fait, T.; Češka, R.

    2008-01-01

    Roč. 29, č. 1 (2008), s. 146-150 ISSN 0172-780X R&D Projects: GA MZd(CZ) NR8328 Institutional research plan: CEZ:AV0Z50110509 Keywords : fenofibrate * rosiglitazone * type 2 diabetes mellitus Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.359, year: 2008

  5. A Cross-Reactivity of Fenofibric Acid With MDMA DRI Assay.

    Science.gov (United States)

    Bugier, Sarah; Garcia-Hejl, Carine; Vest, Philippe; Plantamura, Julie; Chianea, Denis; Renard, Christophe

    2016-09-01

    Within the framework of routine fitness examinations, French Air Force military crew underwent urine testing for 3,4 methylenedioxymetamphetamine (MDMA [ecstasy]). The cross-reactivity of a dyslipidemic drug, fenofibrate, with an MDMA immunoassay was studied and confirmed on a large population sample. A 3-year retrospective study was performed on the MDMA DRI Ecstasy Assay on the Unicel DXC 600. In the event of positive test result, a confirmatory testing was carried out by gas chromatography/mass spectrometry (GC/MS) to establish the presence of MDMA. When analysis by GC/MS did not confirm the presence of MDMA, a false-positive result was suspected and the samples were analyzed by high-performance liquid chromatography-mass spectrometry to identify a potential interfering substance. A total of 15,169 urine samples, from 7,803 patients, were tested for 3 years. Of the tested samples, 22 (0.15%) were positive by DRI Ecstasy Assay. None of them were positive by GC/MS. A cross-reactivity of fenofibrate's metabolite with MDMA using this assay was systematically found. Fenofibrate's interference with MDMA immunoassay was confirmed. Fenofibrate being widely prescribed, physicians had to be alerted that this treatment could lead to false-positive results. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

  6. Fenofibrate, but not ezetimibe, prevents fatty liver disease in mice lacking phosphatidylethanolamineN-methyltransferase.

    Science.gov (United States)

    van der Veen, Jelske N; Lingrell, Susanne; Gao, Xia; Takawale, Abhijit; Kassiri, Zamaneh; Vance, Dennis E; Jacobs, René L

    2017-04-01

    Mice lacking phosphatidylethanolamine N -methyltransferase (PEMT) are protected from high-fat diet (HFD)-induced obesity and insulin resistance. However, these mice develop severe nonalcoholic fatty liver disease (NAFLD) when fed the HFD, which is mainly due to inadequate secretion of VLDL particles. Our aim was to prevent NAFLD development in mice lacking PEMT. We treated Pemt -/- mice with either ezetimibe or fenofibrate to see if either could ameliorate liver disease in these mice. Ezetimibe treatment did not reduce fat accumulation in Pemt -/- livers, nor did it reduce markers for hepatic inflammation or fibrosis. Fenofibrate, conversely, completely prevented the development of NAFLD in Pemt -/- mice: hepatic lipid levels, as well as markers of endoplasmic reticulum stress, inflammation, and fibrosis, in fenofibrate-treated Pemt -/- mice were similar to those in Pemt +/+ mice. Importantly, Pemt -/- mice were still protected against HFD-induced obesity and insulin resistance. Moreover, fenofibrate partially reversed hepatic steatosis and fibrosis in Pemt -/- mice when treatment was initiated after NAFLD had already been established. Increasing hepatic fatty acid oxidation can compensate for the lower VLDL-triacylglycerol secretion rate and prevent/reverse fatty liver disease in mice lacking PEMT. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  7. Comparative transcriptomic and metabolomic analysis of fenofibrate and fish oil treatments in mice

    NARCIS (Netherlands)

    Lu, Y.; Boekschoten, M.V.; Wopereis, S.; Muller, M.R.; Kersten, A.H.

    2011-01-01

    Elevated circulating triglycerides, which are considered a risk factor for cardiovascular disease, can be targeted by treatment with fenofibrate or fish oil. To gain insight into underlying mechanisms, we carried out a comparative transcriptomics and metabolomics analysis of the effect of 2 wk

  8. Comparative transcriptomics and metabolomic analysis of fenofibrate and fish oil treatments in mice

    NARCIS (Netherlands)

    Lu Yingchang (Kevin), Y.; Boekschoten, Mark; Wopereis, Suzan; Muller, Michael; Kersten, Sander

    2011-01-01

    Elevated circulating triglycerides, which are considered a risk factor for cardiovascular disease, can be targeted by treatment with fenofibrate or fish oil. To gain insight into underlying mechanisms, we carried out a comparative transcriptomics and metabolomics analysis of the effect of 2 week

  9. A mechanism-based pharmacokinetic model of fenofibrate for explaining increased drug absorption after food consumption.

    Science.gov (United States)

    Back, Hyun-Moon; Song, Byungjeong; Pradhan, Sudeep; Chae, Jung-Woo; Han, Nayoung; Kang, Wonku; Chang, Min Jung; Zheng, Jiao; Kwon, Kwang-Il; Karlsson, Mats O; Yun, Hwi-Yeol

    2018-01-25

    Oral administration of drugs is convenient and shows good compliance but it can be affected by many factors in the gastrointestinal (GI) system. Consumption of food is one of the major factors affecting the GI system and consequently the absorption of drugs. The aim of this study was to develop a mechanistic GI absorption model for explaining the effect of food on fenofibrate pharmacokinetics (PK), focusing on the food type and calorie content. Clinical data from a fenofibrate PK study involving three different conditions (fasting, standard meals and high-fat meals) were used. The model was developed by nonlinear mixed effect modeling method. Both linear and nonlinear effects were evaluated to explain the impact of food intake on drug absorption. Similarly, to explain changes in gastric emptying time for the drug due to food effects was evaluated. The gastric emptying rate increased by 61.7% during the first 6.94 h after food consumption. Increased calories in the duodenum increased the absorption rate constant of the drug in fed conditions (standard meal = 16.5%, high-fat meal = 21.8%) compared with fasted condition. The final model displayed good prediction power and precision. A mechanistic GI absorption model for quantitatively evaluating the effects of food on fenofibrate absorption was successfully developed, and acceptable parameters were obtained. The mechanism-based PK model of fenofibrate can quantify the effects of food on drug absorption by food type and calorie content.

  10. Bacterial peptidoglycan stimulates adipocyte lipolysis via NOD1.

    Directory of Open Access Journals (Sweden)

    Wendy Chi

    Full Text Available Obesity is associated with inflammation that can drive metabolic defects such as hyperlipidemia and insulin resistance. Specific metabolites can contribute to inflammation, but nutrient intake and obesity are also associated with altered bacterial load in metabolic tissues (i.e. metabolic endotoxemia. These bacterial cues can contribute to obesity-induced inflammation. The specific bacterial components and host receptors that underpin altered metabolic responses are emerging. We previously showed that Nucleotide-binding oligomerization domain-containing protein 1 (NOD1 activation with bacterial peptidoglycan (PGN caused insulin resistance in mice. We now show that PGN induces cell-autonomous lipolysis in adipocytes via NOD1. Specific bacterial PGN motifs stimulated lipolysis in white adipose tissue (WAT explants from WT, but not NOD1⁻/⁻mice. NOD1-activating PGN stimulated mitogen activated protein kinases (MAPK,protein kinase A (PKA, and NF-κB in 3T3-L1 adipocytes. The NOD1-mediated lipolysis response was partially reduced by inhibition of ERK1/2 or PKA alone, but not c-Jun N-terminal kinase (JNK. NOD1-stimulated lipolysis was partially dependent on NF-κB and was completely suppressed by inhibiting ERK1/2 and PKA simultaneously or hormone sensitive lipase (HSL. Our results demonstrate that bacterial PGN stimulates lipolysis in adipocytes by engaging a stress kinase, PKA, NF-κB-dependent lipolytic program. Bacterial NOD1 activation is positioned as a component of metabolic endotoxemia that can contribute to hyperlipidemia, systemic inflammation and insulin resistance by acting directly on adipocytes.

  11. Increased extracellular and intracellular Ca{sup 2+} lead to adipocyte accumulation in bone marrow stromal cells by different mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Ryota, E-mail: hryota@juntendo.ac.jp [Department of Physiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Katoh, Youichi, E-mail: katoyo@juntendo-urayasu.jp [Juntendo University Faculty of International Liberal Arts, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Cardiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Miyamoto, Yuki [Juntendo University Faculty of Health Care and Nursing, Takasu 2-5-1, Urayasu-shi, Chiba 279-0023 (Japan); Itoh, Seigo; Daida, Hiroyuki [Department of Cardiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan); Nakazato, Yuji [Center for Environmental Research, Department of Cardiology, Juntendo University Faculty of Medicine Urayasu Hospital, Tomioka 2-1-1, Urayasu-shi, Chiba 279-0022 (Japan); Okada, Takao [Department of Physiology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2015-02-20

    Mesenchymal stem cells found in bone marrow stromal cells (BMSCs) are the common progenitors for both adipocyte and osteoblast. An increase in marrow adipogenesis is associated with age-related osteopenia and anemia. Both extracellular and intracellular Ca{sup 2+} ([Ca{sup 2+}]{sub o} and [Ca{sup 2+}]{sub i}) are versatile signaling molecules that are involved in the regulation of cell functions, including proliferation and differentiation. We have recently reported that upon treatment of BMSCs with insulin and dexamethasone, both high [Ca{sup 2+}]{sub o} and high [Ca{sup 2+}]{sub i} enhanced adipocyte accumulation, which suggested that increases in [Ca{sup 2+}]{sub o} caused by bone resorption may accelerate adipocyte accumulation in aging and diabetic patients. In this study, we used primary mouse BMSCs to investigate the mechanisms by which high [Ca{sup 2+}]{sub o} and high [Ca{sup 2+}]{sub i} may enhance adipocyte accumulation. In the process of adipocyte accumulation, two important keys are adipocyte differentiation and the proliferation of BMSCs, which have the potential to differentiate into adipocytes. Use of MTT assay and real-time RT-PCR revealed that high [Ca{sup 2+}]{sub i} (ionomycin)-dependent adipocyte accumulation is caused by enhanced proliferation of BMSCs but not enhanced differentiation into adipocytes. Using fura-2 fluorescence-based approaches, we showed that high [Ca{sup 2+}]{sub o} (addition of CaCl{sub 2}) leads to increases in [Ca{sup 2+}]{sub i}. Flow cytometric methods revealed that high [Ca{sup 2+}]{sub o} suppressed the phosphorylation of ERK independently of intracellular Ca{sup 2+}. The inhibition of ERK by U0126 and PD0325901 enhanced the differentiation of BMSCs into adipocytes. These data suggest that increased extracellular Ca{sup 2+} provides the differentiation of BMSCs into adipocytes by the suppression of ERK activity independently of increased intracellular Ca{sup 2+}, which results in BMSC proliferation. - Highlights:

  12. Effects of glucocorticoids on human brown adipocytes.

    Science.gov (United States)

    Barclay, Johanna L; Agada, Hadiya; Jang, Christina; Ward, Micheal; Wetzig, Neil; Ho, Ken K Y

    2015-02-01

    Clinical cases of glucocorticoid (GC) excess are characterized by increased fat mass and obesity through the accumulation of white adipocytes. The effects of GCs on growth and function of brown adipose tissue are unknown and may contribute to the negative energy balance observed clinically. This study aims to evaluate the effect of GCs on proliferation, differentiation, and metabolic function of brown adipocytes. Human brown adipocytes sourced from supraclavicular fat biopsies were grown in culture and differentiated to mature adipocytes. Human white adipocytes sourced from subcutaneous abdominal fat biopsies were cultured as controls. Effects of dexamethasone on growth, differentiation (UCP1, CIDEA, and PPARGC1A expression), and function (oxygen consumption rate (OCR)) of brown adipocytes were quantified. Dexamethasone (1 μM) significantly stimulated the proliferation of brown preadipocytes and reduced that of white preadipocytes. During differentiation, dexamethasone (at 0.1, 1, and 10 μM) stimulated the expression of UCP1, CIDEA, and PPARGC1A in a concentration-dependent manner and enhanced by fourfold to sixfold the OCR of brown adipocytes. Isoprenaline (100 nM) significantly increased (Peffects were significantly reduced (Peffects on development and function of brown adipocytes. These findings provide strong evidence for an effect of GCs on the biology of human brown adipose tissue (BAT) and for the involvement of the BAT system in the metabolic manifestation of Cushing's syndrome. © 2015 Society for Endocrinology.

  13. Interleukin-1β mediates macrophage-induced impairment of insulin signaling in human primary adipocytes.

    Science.gov (United States)

    Gao, Dan; Madi, Mohamed; Ding, Cherlyn; Fok, Matthew; Steele, Thomas; Ford, Christopher; Hunter, Leif; Bing, Chen

    2014-08-01

    Adipose tissue expansion during obesity is associated with increased macrophage infiltration. Macrophage-derived factors significantly alter adipocyte function, inducing inflammatory responses and decreasing insulin sensitivity. Identification of the major factors that mediate detrimental effects of macrophages on adipocytes may offer potential therapeutic targets. IL-1β, a proinflammatory cytokine, is suggested to be involved in the development of insulin resistance. This study investigated the role of IL-1β in macrophage-adipocyte cross-talk, which affects insulin signaling in human adipocytes. Using macrophage-conditioned (MC) medium and human primary adipocytes, we examined the effect of IL-1β antagonism on the insulin signaling pathway. Gene expression profile and protein abundance of insulin signaling molecules were determined, as was the production of proinflammatory cytokine/chemokines. We also examined whether IL-1β mediates MC medium-induced alteration in adipocyte lipid storage. MC medium and IL-1β significantly reduced gene expression and protein abundance of insulin signaling molecules, including insulin receptor substrate-1, phosphoinositide 3-kinase p85α, and glucose transporter 4 and phosphorylation of Akt. In contrast, the expression and release of the proinflammatory markers, including IL-6, IL-8, monocyte chemotactic protein-1, and chemokine (C-C motif) ligand 5 by adipocytes were markedly increased. These changes were significantly reduced by blocking IL-1β activity, its receptor binding, or its production by macrophages. MC medium-inhibited expression of the adipogenic factors and -stimulated lipolysis was also blunted with IL-1β neutralization. We conclude that IL-1β mediates, at least in part, the effect of macrophages on insulin signaling and proinflammatory response in human adipocytes. Blocking IL-1β could be beneficial for preventing obesity-associated insulin resistance and inflammation in human adipose tissue. Copyright

  14. Fenofibrate in the treatment of dyslipidemia: a review of the data as they relate to the new suprabioavailable tablet formulation.

    Science.gov (United States)

    Najib, Jadwiga

    2002-12-01

    The fibric acid derivative fenofibrate is indicated as an adjunct to dietary modification in adults with primary hypercholesterolemia or mixed dyslipidemia (types IIa and IIb hyperlipidemia, Fredrickson classification) to reduce levels of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TG), and apolipoprotein (apo) B, and to increase levels of high-density lipoprotein cholesterol (HDL-C) and apo A. It is also indicated as adjunctive therapy to diet for the treatment of hypertriglyceridemia (types IV and V hyperlipidemia). Initially approved in the United States in a micronized capsule formulation, fenofibrate is now available in a new "suprabioavailable" tablet formulation that has increased bioavailability, achieving equivalent plasma concentrations at lower doses. The 67- and 200-mg micronized capsules can be considered equivalent to the 54- and 160-mg suprabioavailable tablets, respectively. This paper reviews the pharmacologic properties, clinical usefulness, and safety profile of fenofibrate in the management of dyslipidemias. Recent studies, abstracts, reviews, and consensus statements published in the English-language literature were identified through searches of MEDLINE (1966-January 2002), International Pharmaceutical Abstracts (1970-January 2002), and PharmaProjects (1990-January 2002) using the search terms fenofibrate, fibrates, hyperlipidemia, hypertriglyceridemia, and dyslipidemia. Fenofibrate is well absorbed after oral administration, with peak plasma levels attained in 6 to 8 hours. The absolute bioavailability of fenofibrate cannot be determined due to its being virtually insoluble in aqueous media suitable for injection; however, after oral administration of a single dose of radiolabeled fenofibrate, approximately 60% of the dose appeared in urine, primarily as fenofibric acid and its glucuronated conjugate, and approximately 25% was excreted in the feces. The apparent volume of distribution is 0.89 L/kg in

  15. Vitamin C modulates the interaction between adipocytes and macrophages.

    Science.gov (United States)

    Garcia-Diaz, Diego F; Campion, Javier; Quintero, Pablo; Milagro, Fermin I; Moreno-Aliaga, Maria J; Martinez, José A

    2011-09-01

    Increased adiposity is related with monocyte infiltration into the adipose tissue that accentuates inflammation. Antioxidant treatments emerge as approaches to counteract this phenomenon. Cocultures of differentiated 3T3-L1 adipocytes and RAW264.7 macrophages were incubated for 24-72 h with/without 100 nM insulin and/or 200 μM vitamin C (VC). Nitric oxide (NO) secretion (24 h) was measured. Also, expression (24 h) and secretion (72 h) of MCP-1, leptin and apelin were analyzed. NO secretion was significantly inhibited by insulin and VC only in cocultures. MCP-1 expression/secretion was enhanced in cocultures. Insulin incubation reduced MCP-1 expression in both cultures and VC only in controls. Both treatments inhibited MCP-1 secretion in cocultures. Apelin gene expression was induced in cocultures. Insulin induced apelin mRNA expression, but VC inhibited its expression in cocultures under insulin treatment. Apelin secretion was notably induced by insulin and inhibited by VC in cocultures. Leptin expression was decreased in coculture, while presented no effects by VC. VC importantly modulates the established pro-inflammatory state in the interaction between adipocytes and macrophages. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Selective Insulin Resistance in Adipocytes*

    Science.gov (United States)

    Tan, Shi-Xiong; Fisher-Wellman, Kelsey H.; Fazakerley, Daniel J.; Ng, Yvonne; Pant, Himani; Li, Jia; Meoli, Christopher C.; Coster, Adelle C. F.; Stöckli, Jacqueline; James, David E.

    2015-01-01

    Aside from glucose metabolism, insulin regulates a variety of pathways in peripheral tissues. Under insulin-resistant conditions, it is well known that insulin-stimulated glucose uptake is impaired, and many studies attribute this to a defect in Akt signaling. Here we make use of several insulin resistance models, including insulin-resistant 3T3-L1 adipocytes and fat explants prepared from high fat-fed C57BL/6J and ob/ob mice, to comprehensively distinguish defective from unaffected aspects of insulin signaling and its downstream consequences in adipocytes. Defective regulation of glucose uptake was observed in all models of insulin resistance, whereas other major actions of insulin such as protein synthesis and anti-lipolysis were normal. This defect corresponded to a reduction in the maximum response to insulin. The pattern of change observed for phosphorylation in the Akt pathway was inconsistent with a simple defect at the level of Akt. The only Akt substrate that showed consistently reduced phosphorylation was the RabGAP AS160 that regulates GLUT4 translocation. We conclude that insulin resistance in adipose tissue is highly selective for glucose metabolism and likely involves a defect in one of the components regulating GLUT4 translocation to the cell surface in response to insulin. PMID:25720492

  17. Monoterpene limonene induces brown fat-like phenotype in 3T3-L1 white adipocytes.

    Science.gov (United States)

    Lone, Jameel; Yun, Jong Won

    2016-05-15

    Several dietary compounds that are able to induce the brown fat-like phenotype in white adipocytes have been considered for treatment of obesity due to their ability to increase energy expenditure. Here, we report that limonene induces the brown fat-like phenotype in 3T3-L1 adipocytes by increasing expression of brown adipocyte-specific genes and proteins. Limonene-induced browning in white adipocytes was investigated by determining expression levels of brown fat-specific genes and proteins by real-time RT-PCR, immunoblot analysis, and immunocytochemical staining. Limonene enhanced mitochondrial biogenesis, as evidenced by increased mitochondrial content and immunofluorescent intensity. Limonene also significantly elevated protein levels of HSL, PLIN, p-AMPK, p-ACC, ACO, COX4, CPT1, and CYT C, suggesting its possible role in enhancement of lipolysis and lipid catabolism. Increased expression of PRDM16, UCP1, C/EBPβ, and other brown fat-specific markers by limonene was possibly mediated by activation of β3-adnergenic receptor (β3-AR), as inhibition of β3-AR inhibited up-regulation of brown fat-specific markers. Similarly, limonene-mediated activation of ERK and up-regulation of key brown adipocyte specific markers were eliminated by treatment with ERK antagonist. Taken together, these results suggest that limonene induces browning of 3T3-L1 adipocytes via activation of β3-AR and the ERK signaling pathway. In conclusion, our findings suggest that limonene plays a dual modulatory role in induction of the brown adipocyte-like phenotype as well as promotion of lipid metabolism and thus may have potential therapeutic implications for treatment of obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. In vitro and in vivo evaluation of a self-microemulsifying drug delivery system for the poorly soluble drug fenofibrate.

    Science.gov (United States)

    Cho, Young-Dae; Park, Young-Joon

    2014-02-01

    Fenofibrate is indicated in hypercholesterolemia and hypertriglyceridemia alone or combined (types IIa, IIb, III, IV, and V dyslipidemias). However, due to its low solubility in water, it has low bioavailability after oral administration. In order to improve the dissolution rate, fenofibrate was formulated into a self-microemulsifying drug delivery system (SMEDDS). We used pseudoternary phase diagrams to evaluate the area of microemulsification, and an in vitro dissolution test was used to investigate the dissolution rate of fenofibrate. The optimized formulation for in vitro dissolution and bioavailability assessment consisted of propylene glycol laurate (Lauroglycol FCC) (60 %), macrogol-15-hydroxystearate (Solutol HS 15) (27 %), and diethylene glycol monoethyl ether (Transcutol-P) (13 %). The mean droplet size of the oil phase in the microemulsion formed by the SMEDDS was 131.1 nm. The dissolution rate of fenofibrate from SMEDDS was significantly higher than that of the reference tablet. In vivo pharmacokinetics study of fenofibrate in beagles administered SMEDDS-A form resulted in a 3.7-fold increase in bioavailability as compared with the reference drug. Our studies suggested that the fenofibrate containing SMEDDS composition can effectively increase the solubility and oral bioavailability of poorly water-soluble drugs.

  19. Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Yoo, Kyeong-Won [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Immune-network Pioneer Research Center, Department of Biochemistry, College of Medicine, Dong-A University, Busan (Korea, Republic of); Song, Seung Ryel [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Do-Sim [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Department of Laboratory of Medicine, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); So, Hong-Seob [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of); Park, Raekil, E-mail: rkpark@wku.ac.kr [Center for Metabolic Function Regulation, and Department of Microbiology, School of Medicine, Wonkwang University, Iksan (Korea, Republic of)

    2013-12-06

    Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation.

  20. Fenofibrate, a peroxisome proliferator-activated receptor α ligand, prevents abnormal liver function induced by a fasting–refeeding process

    International Nuclear Information System (INIS)

    Lee, Joon No; Dutta, Raghbendra Kumar; Kim, Seul-Gi; Lim, Jae-Young; Kim, Se-Jin; Choe, Seong-Kyu; Yoo, Kyeong-Won; Song, Seung Ryel; Park, Do-Sim; So, Hong-Seob; Park, Raekil

    2013-01-01

    Highlights: •A fasting–refeeding high fat diet (HDF) model mimics irregular eating habit. •A fasting–refeeding HFD induces liver ballooning injury. •A fasting–refeeding HDF process elicits hepatic triglyceride accumulation. •Fenofibrate, PPARα ligand, prevents liver damage induced by refeeding HFD. -- Abstract: Fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, is an anti-hyperlipidemic agent that has been widely used in the treatment of dyslipidemia. In this study, we examined the effect of fenofibrate on liver damage caused by refeeding a high-fat diet (HFD) in mice after 24 h fasting. Here, we showed that refeeding HFD after fasting causes liver damage in mice determined by liver morphology and liver cell death. A detailed analysis revealed that hepatic lipid droplet formation is enhanced and triglyceride levels in liver are increased by refeeding HFD after starvation for 24 h. Also, NF-κB is activated and consequently induces the expression of TNF-α, IL1-β, COX-2, and NOS2. However, treating with fenofibrate attenuates the liver damage and triglyceride accumulation caused by the fasting–refeeding HFD process. Fenofibrate reduces the expression of NF-κB target genes but induces genes for peroxisomal fatty acid oxidation, peroxisome biogenesis and mitochondrial fatty acid oxidation. These results strongly suggest that the treatment of fenofibrate ameliorates the liver damage induced by fasting–refeeding HFD, possibly through the activation of fatty acid oxidation

  1. High Density Lipoprotein Structural Changes and Drug Response in Lipidomic Profiles following the Long-Term Fenofibrate Therapy in the FIELD Substudy

    DEFF Research Database (Denmark)

    Yetukuri, L.; Huopaniemi, I.; Koivuniemi, A.

    2011-01-01

    In a recent FIELD study the fenofibrate therapy surprisingly failed to achieve significant benefit over placebo in the primary endpoint of coronary heart disease events. Increased levels of atherogenic homocysteine were observed in some patients assigned to fenofibrate therapy but the molecular...... of lysophosphatidylcholines and increase of sphingomyelins. Ethanolamine plasmalogens were diminished only in a subgroup of fenofibrate-treated patients with elevated homocysteine levels. Finally we performed molecular dynamics simulations to qualitatively reconstitute HDL particles in silico. We found that increased number...

  2. Human thermogenic adipocytes: a reflection on types of adipocyte, developmental origin, and potential application.

    Science.gov (United States)

    Chu, Dinh-Toi; Tao, Yang

    2017-02-01

    Obesity is a leading health problem facing the modern world; however, no effective therapy for this health issue has yet been developed. A promising research direction to identify novel therapies to prevent obesity has emerged from discoveries on development and function of brown/brite adipocytes in mammals. Importantly, there is evidence for the presence and function of active thermogenic brown adipocytes in both infants and adult humans. Several new investigations have shown that thermogenic adipocytes are beneficial to maintain glucose homeostasis, insulin sensitivity, and a healthy body fat content. Such thermogenic adipocytes have been considered as targets to develop a therapy for preventing obesity. This short review seeks to highlight recent findings on the development and function of brown/brite adipocytes in humans and to discuss potential treatments based on these adipocytes to reduce obesity and its related disorders.

  3. Activation of Sterol Regulatory Element Binding Factors by Fenofibrate and Gemfibrozil Stimulate Myelination in Zebrafish

    Directory of Open Access Journals (Sweden)

    Yuhei Nishimura

    2016-07-01

    Full Text Available Oligodendrocytes are major myelin-producing cells and play essential roles in the function of a healthy nervous system. However, they are also one of the most vulnerable neural cell types in the central nervous system (CNS, and myelin abnormalities in the CNS are found in a wide variety of neurological disorders, including multiple sclerosis, adrenoleukodystrophy, and schizophrenia. There is an urgent need to identify small molecular weight compounds that can stimulate myelination. In this study, we performed comparative transcriptome analysis to identify pharmacodynamic effects common to miconazole and clobetasol, which have been shown to stimulate myelination by mouse oligodendrocyte progenitor cells (OPCs. Of the genes differentially expressed in both miconazole- and clobetasol-treated mouse OPCs compared with untreated cells, we identified differentially expressed genes (DEGs common to both drug treatments. Gene ontology analysis revealed that these DEGs are significantly associated with the sterol biosynthetic pathway, and further bioinformatics analysis suggested that sterol regulatory element binding factors (SREBFs might be key upstream regulators of the DEGs. In silico screening of a public database for chemicals associated with SREBF activation identified fenofibrate, a peroxisome proliferator-activated receptor α (PPARα agonist, as a drug that increases the expression of known SREBF targets, raising the possibility that fenofibrate may also stimulate myelination. To test this, we performed in vivo imaging of zebrafish expressing a fluorescent reporter protein under the control of the myelin basic protein (mbp promoter. Treatment of zebrafish with fenofibrate significantly increased expression of the fluorescent reporter compared with untreated zebrafish. This increase was attenuated by co-treatment with fatostatin, a specific inhibitor of SREBFs, confirming that the fenofibrate effect was mediated via SREBFs. Furthermore, incubation

  4. Activation of Sterol Regulatory Element Binding Factors by Fenofibrate and Gemfibrozil Stimulates Myelination in Zebrafish.

    Science.gov (United States)

    Ashikawa, Yoshifumi; Nishimura, Yuhei; Okabe, Shiko; Sasagawa, Shota; Murakami, Soichiro; Yuge, Mizuki; Kawaguchi, Koki; Kawase, Reiko; Tanaka, Toshio

    2016-01-01

    Oligodendrocytes are major myelin-producing cells and play essential roles in the function of a healthy nervous system. However, they are also one of the most vulnerable neural cell types in the central nervous system (CNS), and myelin abnormalities in the CNS are found in a wide variety of neurological disorders, including multiple sclerosis, adrenoleukodystrophy, and schizophrenia. There is an urgent need to identify small molecular weight compounds that can stimulate myelination. In this study, we performed comparative transcriptome analysis to identify pharmacodynamic effects common to miconazole and clobetasol, which have been shown to stimulate myelination by mouse oligodendrocyte progenitor cells (OPCs). Of the genes differentially expressed in both miconazole- and clobetasol-treated mouse OPCs compared with untreated cells, we identified differentially expressed genes (DEGs) common to both drug treatments. Gene ontology analysis revealed that these DEGs are significantly associated with the sterol biosynthetic pathway, and further bioinformatics analysis suggested that sterol regulatory element binding factors (SREBFs) might be key upstream regulators of the DEGs. In silico screening of a public database for chemicals associated with SREBF activation identified fenofibrate, a peroxisome proliferator-activated receptor α (PPARα) agonist, as a drug that increases the expression of known SREBF targets, raising the possibility that fenofibrate may also stimulate myelination. To test this, we performed in vivo imaging of zebrafish expressing a fluorescent reporter protein under the control of the myelin basic protein (mbp) promoter. Treatment of zebrafish with fenofibrate significantly increased expression of the fluorescent reporter compared with untreated zebrafish. This increase was attenuated by co-treatment with fatostatin, a specific inhibitor of SREBFs, confirming that the fenofibrate effect was mediated via SREBFs. Furthermore, incubation of zebrafish

  5. Reduction of food intake by fenofibrate is associated with cholecystokinin release in long-evanstokushima rats

    Directory of Open Access Journals (Sweden)

    S Yu Vorotnikova

    2012-09-01

    Full Text Available Реферат по статье: Reduction of food intake by fenofibrate is associated with cholecystokinin release in long-evanstokushima rats Park MK, Han Y, Kim MS, Seo E, Kang S, Park SY, Koh H, Kim DK, Lee HJ. Korean J Physiol Pharmacol Vol 16: 181-186, June, 2012

  6. Molecular dynamics of amorphous pharmaceutical fenofibrate studied by broadband dielectric spectroscopy

    Directory of Open Access Journals (Sweden)

    U. Sailaja

    2016-06-01

    Full Text Available Fenofibrate is mainly used to reduce cholesterol level in patients at risk of cardiovascular disease. Thermal transition study with the help of differential scanning calorimetry (DSC shows that the aforesaid active pharmaceutical ingredient (API is a good glass former. Based on our DSC study, the molecular dynamics of this API has been carried out by broadband dielectric spectroscopy (BDS covering wide temperature and frequency ranges. Dielectric measurements of amorphous fenofibrate were performed after its vitrification by fast cooling from a few degrees above the melting point (Tm=354.11 K to deep glassy state. The sample does not show any crystallization tendency during cooling and reaches the glassy state. The temperature dependence of the structural relaxation has been fitted by single Vogel–Fulcher–Tamman (VFT equation. From VFT fit, glass transition temperature (Tg was estimated as 250.56 K and fragility (m was determined as 94.02. This drug is classified as a fragile glass former. Deviations of experimental data from Kohlrausch–Williams–Watts (KWW fits on high-frequency flank of α-peak indicate the presence of an excess wing in fenofibrate. Based on Ngai׳s coupling model, we identified the excess wing as true Johari–Goldstein (JG process. Below the glass transition temperature one can clearly see a secondary relaxation (γ with an activation energy of 32.67 kJ/mol.

  7. TCF7L2 polymorphisms and inflammatory markers before and after treatment with fenofibrate

    Directory of Open Access Journals (Sweden)

    Kabagambe Edmond K

    2009-10-01

    Full Text Available Abstract Background Inflammation is implicated in causing diabetes. We tested whether transcription factor 7 like-2 (TCF7L2 gene polymorphisms (rs12255372 and rs7903146, consistently associated with type 2 diabetes, are associated with plasma concentrations of inflammatory markers before and after three weeks of daily treatment with fenofibrate. Methods Men and women in the Genetics of Lipid-Lowering Drugs and Diet Network study (n = 1025, age 49 ± 16 y were included. All participants suspended use of lipid-lowering drugs for three weeks and were then given 160 mg/day of fenofibrate for three weeks. Inflammatory markers and lipids were measured before and after fenofibrate. ANOVA was used to test for differences across TCF7L2 genotypes. Results Under the additive or dominant model, there were no significant differences (P > 0.05 in the concentrations of inflammatory markers (hsCRP, IL-2, IL-6, TNF-α and MCP-1 across TCF7L2 genotypes in the period before or after treatment. For both rs12255372 and rs7903146, homozygote T-allele carriers had significantly higher (P Conclusion Overall these data show no association between TCF7L2 polymorphisms and the inflammatory markers suggesting that the effects of TCF7L2 on diabetes may not be via inflammation.

  8. Simultaneous determination of atorvastatin calcium, ezetimibe, and fenofibrate in a tablet formulation by HPLC.

    Science.gov (United States)

    Patel, Archita; Macwana, Chhaya; Parmar, Vishal; Patel, Samir

    2012-01-01

    An accurate, simple, reproducible, and sensitive HPLC method was developed and validated for the simultaneous determination of atorvastatin calcium, ezetimibe, and fenofibrate in a tablet formulation. The analyses were performed on an RP C18 column, 150 x 4.60 mm id, 5 pm particle size. The mobile phase methanol-acetonitrile-water (76 + 13 + 11, v/v/v), was pumped at a constant flow rate of 1 mL/min. UV detection was performed at 253 nm. Retention times of atorvastatin calcium, ezetimibe, and fenofibrate were found to be 2.25, 3.68, and 6.41 min, respectively. The method was validated in terms of linearity, precision, accuracy, LOD, LOQ, and robustness. The response was linear in the range 2-10 microg/mL (r2 = 0.998) for atorvastatin calcium, 2-10 microg/mL (r2 = 0.998) for ezetimibe, and 40-120 microg/mL (r2 = 0.998) for fenofibrate. The developed method can be used for routine quality analysis of the drugs in the tablet formulation.

  9. Rosiglitazone drives cavin-2/SDPR expression in adipocytes in a CEBPα-dependent manner.

    Directory of Open Access Journals (Sweden)

    Björn Hansson

    Full Text Available Caveolae are abundant adipocyte surface domains involved in insulin signaling, membrane trafficking and lipid homeostasis. Transcriptional control mechanisms for caveolins and cavins, the building blocks of caveolae, are thus arguably important for adipocyte biology and studies in this area may give insight into insulin resistance and diabetes. Here we addressed the hypothesis that one of the less characterized caveolar components, cavin-2 (SDPR, is controlled by CCAAT/Enhancer Binding Protein (CEBPα and Peroxisome Proliferator-Activated Receptor Gamma (PPARG. Using human mRNA expression data we found that SDPR correlated with PPARG in several tissues. This was also observed during differentiation of 3T3-L1 fibroblasts into adipocytes. Treatment of 3T3-L1-derived adipocytes with the PPARγ-activator Rosiglitazone increased SDPR and CEBPα expression at both the mRNA and protein levels. Silencing of CEBPα antagonized these effects. Further, adenoviral expression of PPARγ/CEBPα or Rosiglitazone-treatment increased SDPR expression in primary rat adipocytes. The myocardin family coactivator MKL1 was recently shown to regulate SDPR expression in human coronary artery smooth muscle cells. However, we found that actin depolymerization, known to inhibit MKL1 and MKL2, was without effect on SDPR mRNA levels in adipocytes, even though overexpression of MKL1 and MKL2 had the capacity to increase caveolins and cavins and to repress PPARγ/CEBPα. Altogether, this work demonstrates that CEBPα expression and PPARγ-activity promote SDPR transcription and further supports the emerging notion that PPARγ/CEBPα and MKL1/MKL2 are antagonistic in adipocytes.

  10. Dynamics of Adipocyte Turnover in Humans

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, K; Arner, E; Westermark, P; Bernard, S; Buchholz, B; Bergmann, O; Blomqvist, L; Hoffstedt, J; Naslund, E; Britton, T; Concha, H; Hassan, M; Ryden, M; Frisen, J; Arner, P

    2007-07-16

    Obesity is increasing in an epidemic fashion in most countries and constitutes a public health problem by enhancing the risk for cardiovascular disease and metabolic disorders such as type 2 diabetes. Owing to the increase in obesity, life expectancy may start to decrease in developed countries for the first time in recent history. The factors determining fat mass in adult humans are not fully understood, but increased lipid storage in already developed fat cells is thought to be most important. We show that adipocyte number is a major determinant for the fat mass in adults. However, the number of fat cells stays constant in adulthood in lean and obese and even under extreme conditions, indicating that the number of adipocytes is set during childhood and adolescence. To establish the dynamics within the stable population of adipocytes in adults, we have measured adipocyte turnover by analyzing the integration of {sup 14}C derived from nuclear bomb tests in genomic DNA. Approximately 10% of fat cells are renewed annually at all adult ages and levels of body mass index. Neither adipocyte death nor generation rate is altered in obesity, suggesting a tight regulation of fat cell number that is independent of metabolic profile in adulthood. The high turnover of adipocytes establishes a new therapeutic target for pharmacological intervention in obesity.

  11. FENOFIBRATE ADMINISTRATION DOES NOT AFFECT MUSCLE TRIGLYCERIDE CONCENTRATION OR INSULIN SENSITIVITY IN HUMANS

    Science.gov (United States)

    Perreault, Leigh; Bergman, Bryan C.; Hunerdosse, Devon M.; Howard, David J.; Eckel, Robert H.

    2010-01-01

    Objective Animal data suggest that males, in particular, rely on PPAR-α activity to maintain normal muscle triglyceride metabolism. We sought to examine whether this was also true in men vs. women and its relationship to insulin sensitivity. Materials/Methods Normolipidemic obese men (n=9) and women (n=9) underwent an assessment of insulin sensitivity (IVGTT) and intramuscular triglyceride metabolism (GC/MS and GC/C/IRMS from plasma and muscle biopsies taken after infusion of [U-13C]palmitate) before and after 12 weeks of fenofibrate treatment. Results Women were more insulin sensitive (Si; 5.2(0.7 vs. 2.4(0.4 ×10−4/uU/ml, W vs. M, ptriglyceride (IMTG) concentration (41.9(15.5 vs. 30.8(5.1 ug/mg dry weight, W vs. M, p=0.43), and IMTG fractional synthesis rate (FSR; 0.27(0.07 vs. 0.35(0.06/hr, W vs. M, p=0.41) as men. Fenofibrate enhanced FSR in men (0.35(0.06 to 0.54(0.06, p=0.05), with no such change seen in women (0.27(0.07 to 0.32(0.13, p=0.73), and no change in IMTG concentration in either group (23.0(3.9 in M, p=0.26 vs. baseline; 36.3(12.0 in W, p=0.79 vs. baseline). Insulin sensitivity was unaffected by fenofibrate (p>0.68). Lower percent saturation of IMTG in women vs. men before (29.1(2.3 vs. 35.2(1.7%, p=0.06) and after (27.3(2.8 vs. 35.1(1.9%, p=0.04) fenofibrate most closely related to their greater insulin sensitivity (R2=0.34, p=0.10), and was largely unchanged by the drug. Conclusions PPAR-α agonist therapy had little effect on IMTG metabolism in men or women. IMTG saturation, rather than IMTG concentration or FSR, most closely (but not significantly) related to insulin sensitivity and was unchanged by fenofibrate administration. PMID:21306746

  12. SDF-1 is an Autocrine Insulin-Desensitizing Factor in Adipocytes.

    Science.gov (United States)

    Shin, Jihoon; Fukuhara, Atsunori; Onodera, Toshiharu; Kita, Shunbun; Yokoyama, Chieko; Otsuki, Michio; Shimomura, Iichiro

    2018-03-26

    Insulin desensitization occurs not only under obese diabetic condition, but also in the fasting state. However, little is known about the common secretory factor(s) that are regulated under these two insulin-desensitized conditions. Here, using database analysis, in vitro , and in vivo experiments, we identified SDF-1 as an insulin-desensitizing factor in adipocytes, overexpressed in both fasting and obese adipose tissues. Exogenously added SDF-1 induced ERK signal, which phosphorylated and degraded IRS-1 protein in adipocytes, decreasing insulin-mediated signaling and glucose uptake. In contrast, knockdown of endogenous SDF-1 or inhibition of its receptor in adipocytes markedly increased IRS-1 protein levels and enhanced insulin sensitivity, indicating the autocrine action of SDF-1. In agreement with these findings, adipocyte-specific ablation of SDF-1 enhanced insulin sensitivity in adipose tissues and whole body. These results point to a novel regulatory mechanism of insulin sensitivity mediated by adipose autocrine SDF-1 action, and provide a new insight into the process of insulin desensitization in adipocytes. © 2018 by the American Diabetes Association.

  13. Enhanced oral bioavailability of fenofibrate using polymeric nanoparticulated systems: physicochemical characterization and in vivo investigation

    Directory of Open Access Journals (Sweden)

    Yousaf AM

    2015-03-01

    Full Text Available Abid Mehmood Yousaf,1 Dong Wuk Kim,1 Yu-Kyoung Oh,2 Chul Soon Yong,3 Jong Oh Kim,3 Han-Gon Choi11College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, 2College of Pharmacy, Seoul National University, Seoul, 3College of Pharmacy, Yeungnam University, Gyongsan, South KoreaBackground: The intention of this research was to prepare and compare various solubility-enhancing nanoparticulated systems in order to select a nanoparticulated formulation with the most improved oral bioavailability of poorly water-soluble fenofibrate.Methods: The most appropriate excipients for different nanoparticulated preparations were selected by determining the drug solubility in 1% (w/v aqueous solutions of each carrier. The polyvinylpyrrolidone (PVP nanospheres, hydroxypropyl-β-cyclodextrin (HP-β-CD nanocorpuscles, and gelatin nanocapsules were formulated as fenofibrate/PVP/sodium lauryl sulfate (SLS, fenofibrate/HP-β-CD, and fenofibrate/gelatin at the optimized weight ratios of 2.5:4.5:1, 1:4, and 1:8, respectively. The three solid-state products were achieved using the solvent-evaporation method through the spray-drying technique. The physicochemical characterization of these nanoparticles was accomplished by powder X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and Fourier-transform infrared spectroscopy. Their physicochemical properties, aqueous solubility, dissolution rate, and pharmacokinetics in rats were investigated in comparison with the drug powder.Results: Among the tested carriers, PVP, HP-β-CD, gelatin, and SLS showed better solubility and were selected as the most appropriate constituents for various nanoparticulated systems. All of the formulations significantly improved the aqueous solubility, dissolution rate, and oral bioavailability of fenofibrate compared to the drug powder. The drug was present in the amorphous form in HP-β-CD nanocorpuscles; however, in

  14. Development and Validation of RP-HPLC Method for Simultaneous Estimation of Atorvastatin Calcium and Fenofibrate in Tablet Dosage Forms.

    Science.gov (United States)

    Jain, N; Raghuwanshi, R; Jain, Deeti

    2008-01-01

    A reverse phase high performance liquid chromatographic method was developed for the simultaneous estimation of atorvastatin calcium and fenofibrate in tablet formulation. The separation was achieved by Luna C18 column and methanol:acetate buffer pH 3.7 (82:18 v/v) as mobile phase, at a flow rate of 1.5 ml/min. Detection was carried out at 248 nm. Retention time of atorvastatin calcium and fenofibrate was found to be 3.02+0.1 and 9.05+0.2 min, respectively. The method has been validated for linearity, accuracy and precision. Linearity for atorvastatin calcium and Fenofibrate were in the range of 1-5 mug/ml and 16-80 mug/ml, respectively. The mean recoveries obtained for Atorvastatin calcium and fenofibrate were 101.76% and 100.06%, respectively. Developed method was found to be accurate, precise, selective and rapid for simultaneous estimation of atorvastatin calcium and fenofibrate in tablets.

  15. Adipocyte nuclei captured from VAT and SAT.

    Science.gov (United States)

    Ambati, Suresh; Yu, Ping; McKinney, Elizabeth C; Kandasamy, Muthugapatti K; Hartzell, Diane; Baile, Clifton A; Meagher, Richard B

    2016-01-01

    Obesity-related comorbidities are thought to result from the reprogramming of the epigenome in numerous tissues and cell types, and in particular, mature adipocytes within visceral and subcutaneous adipose tissue, VAT and SAT. The cell-type specific chromatin remodeling of mature adipocytes within VAT and SAT is poorly understood, in part, because of the difficulties of isolating and manipulating large fragile mature adipocyte cells from adipose tissues. We constructed MA-INTACT (Mature Adipocyte-Isolation of Nuclei TAgged in specific Cell Types) mice using the adiponectin (ADIPOQ) promoter (ADNp) to tag the surface of mature adipocyte nuclei with a reporter protein. The SUN1mRFP1Flag reporter is comprised of a fragment of the nuclear transmembrane protein SUN1, the fluorescent protein mRFP1, and three copies of the Flag epitope tag. Mature adipocyte nuclei were rapidly and efficiently immuno-captured from VAT and SAT (MVA and MSA nuclei, respectively), of MA-INTACT mice. MVA and MSA nuclei contained 1,000 to 10,000-fold higher levels of adipocyte-specific transcripts, ADIPOQ, PPARg2, EDNRB, and LEP, relative to uncaptured nuclei, while the latter expressed higher levels of leukocyte and endothelial cell markers IKZF1, RETN, SERPINF1, SERPINE1, ILF3, and TNFA. MVA and MSA nuclei differentially expressed several factors linked to adipogenesis or obesity-related health risks including CEBPA, KLF2, RETN, SERPINE1, and TNFA. The various nuclear populations dramatically differentially expressed transcripts encoding chromatin remodeler proteins regulating DNA cytosine methylation and hydroxymethylation (TETs, DNMTs, TDG, GADD45s) and nucleosomal histone modification (ARID1A, KAT2B, KDM4A, PRMT1, PRMT5, PAXIP1). Remarkably, MSA and MVA nuclei expressed 200 to 1000-fold higher levels of thermogenic marker transcripts PRDM16 and UCP1. The MA-INTACT mouse enables a simple way to perform cell-type specific analysis of highly purified mature adipocyte nuclei from VAT and SAT

  16. Human adipocyte extracellular vesicles in reciprocal signaling between adipocytes and macrophages

    NARCIS (Netherlands)

    Kranendonk, Mariëtte E G; Visseren, Frank L J; van Balkom, Bas W M; Nolte-'t Hoen, Esther N M; van Herwaarden, Joost A; de Jager, Wilco; Schipper, Henk S; Brenkman, Arjan B; Verhaar, Marianne C; Wauben, Marca H M; Kalkhoven, Eric

    2014-01-01

    OBJECTIVE: Extracellular vesicles (EVs) released by human adipocytes or adipose tissue (AT)-explants play a role in the paracrine interaction between adipocytes and macrophages, a key mechanism in AT inflammation, leading to metabolic complications like insulin resistance (IR) were determined.

  17. File list: His.Adp.10.AllAg.White_adipocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Adp.10.AllAg.White_adipocytes mm9 Histone Adipocyte White adipocytes SRX800009 ...http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Adp.10.AllAg.White_adipocytes.bed ...

  18. File list: His.Adp.50.AllAg.White_adipocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Adp.50.AllAg.White_adipocytes mm9 Histone Adipocyte White adipocytes SRX800009 ...http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Adp.50.AllAg.White_adipocytes.bed ...

  19. Kolliphor surfactants affect solubilization and bioavailability of fenofibrate. Studies of in vitro digestion and absorption in rats

    DEFF Research Database (Denmark)

    Berthelsen, Ragna; Holm, Rene; Jacobsen, Jette

    2015-01-01

    Selection of excipients for drug formulations requires both intellectual and experimental considerations as many of the used excipients are affected by physiological factors, e.g., they may be digested by pancreatic enzymes in the gastrointestinal tract. In the present paper we have looked...... formulations only comprised an aqueous micellar solution of the model drug (fenofibrate) in varying concentrations (2–25% (w/v)) of the three tested surfactants. Increased concentrations of Kolliphor ELP and EL led to increased fenofibrate AUC0–24h values. For the Kolliphor RH40 formulations, an apparent...... choice for solubilizing fenofibrate in order to increase the absorption upon oral administration. Due to drug dependent effects of the different types of Kolliphor, more studies are recommended in order to understand which type of Kolliphor is best suited for a given drug....

  20. Can thermogenic adipocytes protect from obesity?

    Science.gov (United States)

    Medvedev, L N; Elsukova, E I

    2015-12-01

    The role of brown adipocytes and adipocytes of a new beige type in the energy metabolism of a healthy person and in the pathogenesis of obesity has extensively been discussed in recent years. The interest to these cells has been stimulated owing to the application of new noninvasive methods for studying the metabolic activity of tissues. Using these methods, the presence of thermogenically active adipocytes in adults and their reactivity to cold stimuli have been proved. These data, together with the results of animal experiments support the idea of thermogenic fat being a direct regulator of the energy balance of man. However, for several reasons there are some objections to this viewpoint. The main objection is that the total activity of the human thermogenic adipocytes is about 100 kJ/day, i.e., it is negligible. In addition, the burn of excessive nutrients is biologically inappropriate for an organism. Therefore, the idea that obesity is caused by the decreased activity of thermogenic adipocytes is erroneous. The statement that the causes of obesity are associated with the increased efficiency of energy-dependent processes seems more reasonable. The consequence is a reduction in energy expenditure to perform a unit of biological work. This results in excess of nutrients deposited in the form of fat.

  1. Adipocyte iron regulates leptin and food intake.

    Science.gov (United States)

    Gao, Yan; Li, Zhonggang; Gabrielsen, J Scott; Simcox, Judith A; Lee, Soh-hyun; Jones, Deborah; Cooksey, Bob; Stoddard, Gregory; Cefalu, William T; McClain, Donald A

    2015-09-01

    Dietary iron supplementation is associated with increased appetite. Here, we investigated the effect of iron on the hormone leptin, which regulates food intake and energy homeostasis. Serum ferritin was negatively associated with serum leptin in a cohort of patients with metabolic syndrome. Moreover, the same inverse correlation was observed in mice fed a high-iron diet. Adipocyte-specific loss of the iron exporter ferroportin resulted in iron loading and decreased leptin, while decreased levels of hepcidin in a murine hereditary hemochromatosis (HH) model increased adipocyte ferroportin expression, decreased adipocyte iron, and increased leptin. Treatment of 3T3-L1 adipocytes with iron decreased leptin mRNA in a dose-dependent manner. We found that iron negatively regulates leptin transcription via cAMP-responsive element binding protein activation (CREB activation) and identified 2 potential CREB-binding sites in the mouse leptin promoter region. Mutation of both sites completely blocked the effect of iron on promoter activity. ChIP analysis revealed that binding of phosphorylated CREB is enriched at these two sites in iron-treated 3T3-L1 adipocytes compared with untreated cells. Consistent with the changes in leptin, dietary iron content was also directly related to food intake, independently of weight. These findings indicate that levels of dietary iron play an important role in regulation of appetite and metabolism through CREB-dependent modulation of leptin expression.

  2. Fish Oil and Fenofibrate for the Treatment of Hypertriglyceridemia in HIV-Infected Subjects on Antiretroviral Therapy

    Science.gov (United States)

    Gerber, John G.; Kitch, Douglas W.; Fichtenbaum, Carl J.; Zackin, Robert A.; Charles, Stéphannie; Hogg, Evelyn; Acosta, Edward P.; Connick, Elizabeth; Wohl, David; Kojic, E. Milu; Benson, Constance A.; Aberg, Judith A.

    2009-01-01

    Introduction Fish oil has been shown to reduce serum triglyceride (TG) concentrations. In HIV-infected patients on antiretroviral therapy, high TG concentrations likely contribute to increased risk of cardiovascular disease. AIDS Clinical Trials Group A5186 examined the safety and efficacy of fish oil plus fenofibrate in subjects not achieving serum TG levels ≤200 mg/dL with either agent alone. Methods One hundred subjects on highly active antiretroviral therapy with serum TG concentrations ≥400 mg/dL and low-density lipoprotein cholesterol ≤160 mg/dL were randomized to 3 g of fish oil twice daily or 160 mg of fenofibrate daily for 8 weeks. Subjects with a fasting TG level >200 mg/dL at week 8 received a combination of fish oil and fenofibrate in the same doses from week 10 to week 18. Results Median baseline TG was 662 mg/dL in the fish oil group and 694 mg/dL in the fenofibrate group (P = not significant). Fish oil reduced TG levels by a median of 283 mg/dL (46%), fenofibrate reduced them by 367 mg/dL (58%), and combination therapy reduced them by 65.5%. Combination therapy achieved TG levels of ≤200 mg/dL in 22.7% subjects. Fish oil had no measurable effect on immunologic parameters or the pharmacokinetics of lopinavir. Conclusions Fish oil was safe when administered alone or combined with fenofibrate and significantly reduced TG levels in HIV-infected subjects with hypertriglyceridemia. PMID:17971707

  3. Effect of insulin and glucocorticoids on glucose transporters in rat adipocytes

    International Nuclear Information System (INIS)

    Carter-Su, C.; Okamoto, K.

    1987-01-01

    The ability of glucocorticoids to modify the effect of insulin on glucose (L-1- 3 H(N)]glucose and D-[ 14 C-U]glucose) transport was investigated in both intact isolated rat adipocytes and in membranes isolated from hormone-treated adipocytes. In intact adipocytes, dexamethasone, a potent synthetic glucocorticoid, inhibited insulin-stimulated 3-O-methylglucose transport at all concentrations of insulin tested. Insulin sensitivity, as well as the maximal response to insulin, was decreased by dexamethasone in the absence of a change in 125 I insulin binding. The inhibition was observed regardless of which hormone acted first, was blocked by actinomycin D, and resulted from a decrease in V/sub max/ rather than an increase in K/sub t/ of transport. In plasma membranes isolated from insulin-treated adipocytes, glucose transport activity and the amount of glucose transporter covalently labeled with [ 3 H]cytochalasin B were increased in parallel in a dose-dependent fashion. The amount of labeled transporter in a low-density microsomal fraction (LDMF) was decreased in a reciprocal fashion. In contrast, addition of dexamethasone to insulin-stimulated cells caused decreases in both transport activity and amount of labeled transporter in the plasma membranes. This was accompanied by a small increase in the amount of [ 3 H]cytochalasin B incorporated into the glucose transporter in the LDMF. These results are consistent with both insulin and glucocorticoids altering the distribution of glucose transporters between the plasma membrane and LDMF, in opposite directions

  4. Empagliflozin lessened cardiac injury and reduced visceral adipocyte hypertrophy in prediabetic rats with metabolic syndrome.

    Science.gov (United States)

    Kusaka, Hiroaki; Koibuchi, Nobutaka; Hasegawa, Yu; Ogawa, Hisao; Kim-Mitsuyama, Shokei

    2016-11-11

    The potential benefit of SGLT2 inhibitors in metabolic syndrome is with prediabetic stage unclear. This work was undertaken to investigate the non-glycemic effect of empagliflozin on metabolic syndrome rats with prediabetes. SHR/NDmcr-cp(+/+) rats (SHRcp), a model of metabolic syndrome with prediabetes, were given empagliflozin for 10 weeks to examine the effects on urinary sodium and water balance, visceral and subcutaneous adipocyte, and cardiac injury. Further, the effect of empagliflozin on blood pressure and autonomic nervous system was continuously investigated by using radiotelemetry system. Empagliflozin significantly reduced urinary sodium and water balance of SHRcp only within 1 week of the treatment, but later than 1 week did not alter them throughout the treatment. Empagliflozin significantly reduced body weight of SHRcp, which was mainly attributed to the significant reduction of subcutaneous fat mass. Empagliflozin significantly reduced the size of visceral adipocytes and increased the number of smaller size of adipocytes, which was associated with the attenuation of oxidative stress. Empagliflozin ameliorated cardiac hypertrophy and fibrosis of SHRcp, in association with the attenuation of cardiac oxidative stress and inflammation. However, empagliflozin did not significantly change blood pressure, heart rate, sympathetic activity, or baroreceptor function, as evidenced by radiotelemetry analysis. Our present work provided the evidence that SGLT2 inhibition reduced visceral adipocytes hypertrophy and ameliorated cardiac injury in prediabetic metabolic syndrome rat, independently of diuretic effect or blood pressure lowering effect. Thus, SGLT2 inhibition seems to be a promising therapeutic strategy for prediabetic metabolic syndrome.

  5. Polyacetylenes from carrots (Daucus carota) improve glucose uptake in vitro in adipocytes and myotubes.

    Science.gov (United States)

    El-Houri, Rime B; Kotowska, Dorota; Christensen, Kathrine B; Bhattacharya, Sumangala; Oksbjerg, Niels; Wolber, Gerhard; Kristiansen, Karsten; Christensen, Lars P

    2015-07-01

    A dichloromethane (DCM) extract of carrot roots was found to stimulate insulin-dependent glucose uptake (GU) in adipocytes in a dose dependent manner. Bioassay-guided fractionation of the DCM extract resulted in the isolation of the polyacetylenes falcarinol and falcarindiol. Both polyacetylenes were able to significantly stimulate basal and/or insulin-dependent GU in 3T3-L1 adipocytes and porcine myotube cell cultures in a dose-dependent manner. Falcarindiol increased peroxisome proliferator-activated receptor (PPAR)γ-mediated transactivation significantly at concentrations of 3, 10 and 30 μM, while PPARγ-mediated transactivation by falcarinol was only observed at 10 μM. Docking studies accordingly indicated that falcarindiol binds to the ligand binding domain of PPARγ with higher affinity than falcarinol and that both polyacetylenes exhibit characteristics of PPARγ partial agonists. Falcarinol was shown to inhibit adipocyte differentiation as evident by gene expression studies and Oil Red O staining, whereas falcarindiol did not inhibit adipocyte differentiation, which indicates that these polyacetylenes have distinct modes of action. The results of the present study suggest that falcarinol and falcarindiol may represent scaffolds for novel partial PPARγ agonists with possible antidiabetic properties.

  6. PAM, OLA, and LNA are Differentially Taken Up and Trafficked Via Different Metabolic Pathways in Porcine Adipocytes.

    Science.gov (United States)

    Yu, Caihua; Xi, Lingling; Chen, Jin; Jiang, Qin; Yi, Hongbo; Wang, Yizhen; Wang, Xinxia

    2017-11-01

    Dietary fatty acids have different effects on fat deposition in pigs. To clarify the underlying mechanisms of this difference, we compared the metabolism of palmitic (PAM, saturated), oleic (OLA, monounsaturated) and linoleic acid (LNA, polyunsaturated) in porcine adipocytes treated with 100 μM PAM, OLA or LNA. We observed that the adipocytes incubated with LNA accumulated more lipids compared with those treated with PAM and OLA. We then probed the metabolism of these fatty acids in porcine adipocytes by using isotope-labelled fatty acids. The results showed that 42% of the [1- 14 C] LNA, 34% of the [1- 14 C] PAM and 28% of the [1- 14 C] OLA were recovered in the cellular lipids. The gene expression analyses showed that LNA significantly increased the expression of adipogenesis- and oxidation-related genes including PPARγ, C/EBPα, ap2 and NRF1. In addition, the cells incubated with LNA showed a decreased Ser 112 phosphorylation in PPARγ compared to those incubated with PAM and OLA. Furthermore, when PPARγ Ser 112 phosphorylation was inhibited, no significant difference in the triacylglycerol contents in the adipocytes was observed. These results showed the dietary fatty acids had different metabolism pathways in porcine adipocytes, and LNA significantly promoted lipid accumulation, probably by regulating PPARγ phosphorylation in adipocytes.

  7. [The fixed combination of pravastatin and fenofibrate: what can it provide?].

    Science.gov (United States)

    Díaz Rodríguez, Ángel

    2014-07-01

    The treatment of patients with high cardiovascular risk and mixed hyperlipidemia is difficult due to multiple quantitative and qualitative lipid abnormalities. The priority is to reduce LDL-c levels, for which statins are the drug of choice. Despite the benefits of statins, the residual cardiovascular risk is very high in patients with atherogenic dyslipidemia. To reduce this risk, we also need to control non-HDL cholesterol levels, decreasing triglyceride levels and increasing HDL-c levels. To achieve these objectives and lifestyle changes, the use of combined therapy is often required. Fibrates are drugs that can be used in combination with statins to reduce this residual risk. Fenofibrate is well tolerated in combination with statins. The fixed combination of pravastatin/ fenofibrate has been shown to have complementary benefits in the atherogenic lipid profile in general. The combination is well tolerated and is indicated in patients with high risk and mixed hyperlipidemia who have controlled or are close to their objectives for LDL-c levels, using 40-mg pravastatin in monotherapy. The beneficial eff ect of the combination on LDL-c levels is minimal and is primarily observed in non-HDL cholesterol, triglycerides and HDL-c. The combination of pravastatin 40 and fenofibrate 160 can provide a considerable clinical benefit to patients with high risk and mixed atherogenic dyslipidemia, to patients with LDL-c levels that are controlled or near the objectives for decreasing their residual risk of lipid origin and is especially useful for patients with type 2 diabetes, obesity and combined metabolic syndrome and familial hyperlipidemia. Copyright © 2014 Sociedad Española de Arteriosclerosis y Elsevier España, S.L. All rights reserved.

  8. Growth hormone receptors in cultured adipocytes: a model to study receptor regulation.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1986-09-01

    Acutely isolated rat adipocytes have been maintained in primary culture for several days and the effects of culture on the kinetics of 125I-human growth hormone (hGH) binding to adipocytes have been determined. A marked increase (500-1000%) in specific binding of 125I-hGH was observed over the first 3 days of culture--acutely isolated adipocytes (5.5 +/- 1.4%, mean +/- SE, n = 47) compared to 3-day cultured adipocytes (48 +/- 7%, mean +/- SE, n = 8). Specific binding of 125I-hGH to both acutely isolated and cultured adipocytes was dependent on incubation time and temperature (equilibrium being reached in 1 h at 37 degrees C and 2 h at 22 degrees C). Binding was reversible (t1/2 approximately 1.5 h). Scatchard analysis revealed linear plots and showed that the increase in binding during culture was due to an increase in the number of receptors per cell (approximately 20 000 to approximately 170 000) with little or no change in binding affinity (Ka approximately 1 X 10(9) M-1). Cycloheximide inhibited the increase in binding sites during culture suggesting a requirement for de novo protein synthesis. Addition of unlabelled hGH to the culture medium resulted in a marked down-regulation of the GH receptor by 2 days. The GH-induced decrease in receptor number was to due to receptor occupancy by exogenously added GH. The studies to date indicate that the cultured rat adipocyte should provide a useful model for a comprehensive study of the cellular mechanisms and dynamics of GH receptor regulation.

  9. Human primary adipocytes exhibit immune cell function: adipocytes prime inflammation independent of macrophages.

    Directory of Open Access Journals (Sweden)

    Kees Meijer

    Full Text Available BACKGROUND: Obesity promotes inflammation in adipose tissue (AT and this is implicated in pathophysiological complications such as insulin resistance, type 2 diabetes and cardiovascular disease. Although based on the classical hypothesis, necrotic AT adipocytes (ATA in obese state activate AT macrophages (ATM that then lead to a sustained chronic inflammation in AT, the link between human adipocytes and the source of inflammation in AT has not been in-depth and systematically studied. So we decided as a new hypothesis to investigate human primary adipocytes alone to see whether they are able to prime inflammation in AT. METHODS AND RESULTS: Using mRNA expression, human preadipocytes and adipocytes express the cytokines/chemokines and their receptors, MHC II molecule genes and 14 acute phase reactants including C-reactive protein. Using multiplex ELISA revealed the expression of 50 cytokine/chemokine proteins by human adipocytes. Upon lipopolysaccharide stimulation, most of these adipocyte-associated cytokines/chemokines and immune cell modulating receptors were up-regulated and a few down-regulated such as (ICAM-1, VCAM-1, MCP-1, IP-10, IL-6, IL-8, TNF-α and TNF-β highly up-regulated and IL-2, IL-7, IL-10, IL-13 and VEGF down-regulated. In migration assay, human adipocyte-derived chemokines attracted significantly more CD4+ T cells than controls and the number of migrated CD4+ cells was doubled after treating the adipocytes with LPS. Neutralizing MCP-1 effect produced by adipocytes reduced CD4+ migration by approximately 30%. CONCLUSION: Human adipocytes express many cytokines/chemokines that are biologically functional. They are able to induce inflammation and activate CD4+ cells independent of macrophages. This suggests that the primary event in the sequence leading to chronic inflammation in AT is metabolic dysfunction in adipocytes, followed by production of immunological mediators by these adipocytes, which is then exacerbated by

  10. Cell Volume Regulation and Signaling in 3T3-L1 Pre-adipocytes and Adipocytes

    DEFF Research Database (Denmark)

    Eduardsen, Kathrine; Larsen, Susanne; Novak, Ivana

    2011-01-01

    no detectable effect on InsR, yet increased ERK1/2 phosphorylation. In conclusion, differentiated 3T3-L1 adipocytes exhibit greatly accelerated RVD and RVI responses and increased swelling-activated taurine efflux compared to pre-adipocytes. Furthermore, in pre-adipocytes, Cav-1/caveolae integrity......) and osmotic cell shrinkage (RVI), accompanied by increased swelling-activated taurine efflux. However, caveolin-1 distribution was not detectably altered after osmotic swelling or shrinkage, and caveolae integrity, as studied by cholesterol depletion or expression of dominant negative Cav-1, was not required...

  11. Aminoclay–lipid hybrid composite as a novel drug carrier of fenofibrate for the enhancement of drug release and oral absorption

    Directory of Open Access Journals (Sweden)

    Yang L

    2016-03-01

    Full Text Available Liang Yang, Yating Shao, Hyo-Kyung Han BK Plus Project Team, College of Pharmacy, Dongguk University, Goyang, South Korea Abstract: This study aimed to prepare the aminoclay–lipid hybrid composite to enhance the drug release and improve the oral bioavailability of poorly water-soluble fenofibrate. Antisolvent precipitation coupled with an immediate freeze-drying method was adopted to incorporate fenofibrate into aminoclay–lipid hybrid composite (ALC. The optimal composition of the ALC formulation was determined as the ratios of aminoclay to krill oil of 3:1 (w/w, krill oil to fenofibrate of 2:1 (w/w, and antisolvent to solvent of 6:4 (v/v. The morphological characteristics of ALC formulation were determined using scanning electron microscopy, differential scanning calorimetry, and X-ray powder diffraction, which indicated microcrystalline state of fenofibrate in ALC formulation. The ALC formulation achieved almost complete dissolution within 30 minutes, whereas the untreated powder and physical mixture exhibited less than 15% drug release. Furthermore, ALC formulation effectively increased the peak plasma concentration (Cmax and area under the curve (AUC of fenofibric acid (an active metabolite in rats by approximately 13- and seven-fold, respectively. Furthermore, ALC formulation exhibited much lower moisture sorption behavior than the lyophilized formulation using sucrose as a cryoprotectant. Taken together, the present findings suggest that ALC formulation is promising for improving the oral absorption of poorly soluble fenofibrate. Keywords: aminoclay, omega-3 phospholipids, fenofibrate, drug release, oral absorption 

  12. Transcription regulator TRIP-Br2 mediates ER stress-induced brown adipocytes dysfunction.

    Science.gov (United States)

    Qiang, Guifen; Whang Kong, Hyerim; Gil, Victoria; Liew, Chong Wee

    2017-01-09

    In contrast to white adipose tissue, brown adipose tissue (BAT) is known to play critical roles for both basal and inducible energy expenditure. Obesity is associated with reduction of BAT function; however, it is not well understood how obesity promotes BAT dysfunction, especially at the molecular level. Here we show that the transcription regulator TRIP-Br2 mediates ER stress-induced inhibition of lipolysis and thermogenesis in BAT. Using in vitro, ex vivo, and in vivo approaches, we demonstrate that obesity-induced inflammation upregulates brown adipocytes TRIP-Br2 expression via the ER stress pathway and amelioration of ER stress in mice completely abolishes high fat diet-induced upregulation of TRIP-Br2 in BAT. We find that increased TRIP-Br2 significantly inhibits brown adipocytes thermogenesis. Finally, we show that ablation of TRIP-Br2 ameliorates ER stress-induced inhibition on lipolysis, fatty acid oxidation, oxidative metabolism, and thermogenesis in brown adipocytes. Taken together, our current study demonstrates a role for TRIP-Br2 in ER stress-induced BAT dysfunction, and inhibiting TRIP-Br2 could be a potential approach for counteracting obesity-induced BAT dysfunction.

  13. Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lasrich, Dorothee; Bartelt, Alexander [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany); Grewal, Thomas, E-mail: thomas.grewal@sydney.edu.au [Faculty of Pharmacy A15, The University of Sydney, Sydney, NSW 2006 (Australia); Heeren, Joerg, E-mail: heeren@uke.de [Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg (Germany)

    2015-09-10

    Several studies in mice indicate a role for apolipoprotein E (APOE) in lipid accumulation and adipogenic differentiation in adipose tissue. However, little is yet known if APOE functions in a similar manner in human adipocytes. This prompted us to compare lipid loading and expression of adipocyte differentiation markers in APOE-deficient and control adipocytes using the differentiated human mesenchymal stem cell line hMSC-Tert as well as primary human and mouse adipocytes as model systems. Differentiated hMSC-Tert were stably transduced with or without siRNA targeting APOE while murine adipocytes were isolated from wild type and Apoe knockout mice. Human APOE knockdown hMSC-Tert adipocytes accumulated markedly less triglycerides compared to control cells. This correlated with strongly decreased gene expression levels of adipocyte markers such as adiponectin (ADIPOQ) and fatty acid binding protein 4 (FABP4) as well as the key transcription factor driving adipocyte differentiation, peroxisome proliferator activator receptor gamma (PPARG), in particular the PPARG2 isoform. Similarly, differentiation of murine Apoe-deficient adipocytes was characterized by reduced gene expression of Adipoq, Fabp4 and Pparg. Interestingly, incubation of APOE-deficient hMSC-Tert adipocytes with conditioned media from APOE3-overexpressing adipocytes or APOE-containing Very Low Density Lipoprotein (VLDL) partially restored triglyceride accumulation, but were unable to induce adipocyte differentiation, as judged by expression of adipocyte markers. Taken together, depletion of endogenous APOE in human adipocytes severely impairs lipid accumulation, which is associated with an inability to initiate differentiation. - Highlights: • Immortalized human mesenchymal stem cells were used to study adipocyte development. • Knockdown of endogenous APOE lead to impaired lipid accumulation and adipogenesis. • APOE supplementation partially restored lipid accumulation but not differentiation.

  14. Vitamin D limits chemokine expression in adipocytes and macrophage migration in vitro and in male mice.

    Science.gov (United States)

    Karkeni, Esma; Marcotorchino, Julie; Tourniaire, Franck; Astier, Julien; Peiretti, Franck; Darmon, Patrice; Landrier, Jean-François

    2015-05-01

    Vitamin D (VD) displays immunoregulatory effects and reduces adipocyte inflammation, which may participate to a reduction of adipose tissue macrophage infiltration in the context of obesity-associated low-grade inflammation. These observations have been described mainly in vitro, through the evaluation of a limited number of inflammatory markers. Here, we studied the effects of 1,25 dihydroxy-VD on chemokine network expression in adipocytes (by transcriptomic approach), and we confirm the physiological relevance of these data in vivo, by demonstrating the effect of VD on cytokine and chemokine gene expression as well as on macrophage infiltration in adipose tissue. 1,25 dihydroxy-VD down-regulated (-1.3- to -10.8-fold) the mRNA expression of 29 chemokines and limited macrophage migration in TNFα-conditioned adipocyte medium (1.5-fold; P < .05). This effect was associated with a reduction in p65 and IκB (nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha) phosphorylation (2-fold compared with TNFα; P < .05). The effects of VD were confirmed in mice injected ip with lipopolysaccharide (acute inflammation) and diet-induced obese mice (metabolic inflammation), where the levels of mRNA encoding proinflammatory cytokines and chemokines (∼2-fold) were reduced in adipocytes (acute and metabolic inflammation) and adipose tissue and that macrophage infiltration was also inhibited in the adipose tissue of obese mice (metabolic inflammation). Altogether, these results showed that VD displayed a global immunoregulatory impact on adipocytes, notably via the inhibition of chemokine expression and macrophage infiltration in inflamed adipose tissue.

  15. Nuclear factor of activated T cell (NFAT) transcription proteins regulate genes involved in adipocyte metabolism and lipolysis

    International Nuclear Information System (INIS)

    Holowachuk, Eugene W.

    2007-01-01

    NFAT involvement in adipocyte physiological processes was examined by treatment with CsA and/or GSK3β inhibitors (Li + or TZDZ-8), which prevent or increase NFAT nuclear translocation, respectively. CsA treatment reduced basal and TNFα-induced rates of lipolysis by 50%. Adipocytes preincubated with Li + or TZDZ-8 prior to CsA and/or TNFα, exhibited enhanced basal rates of lipolysis and complete inhibition of CsA-mediated decreased rates of lipolysis. CsA treatment dramatically reduced the mRNA levels of adipocyte-specific genes (aP2, HSL, PPARγ, ACS and Adn), compared with control or TNFα-treatment, whereas Li + pretreatment blocked the inhibitory effects of CsA, and mRNA levels of aP2, HSL, PPARγ, and ACS were found at or above control levels. NFAT nuclear localization, assessed by EMSA, confirmed that CsA or Li + treatments inhibited or increased NFAT nuclear translocation, respectively. These results show that NFAT proteins in mature adipocytes participate in the transcriptional control of genes involved in adipocyte metabolism and lipolysis

  16. Modulating the Genomic Programming of Adipocytes

    DEFF Research Database (Denmark)

    Loft, Anne; Schmidt, Søren Fisker; Mandrup, Susanne

    2015-01-01

    , an antidiabetic agonist of the key adipocyte transcription factor peroxisome proliferator-activated receptor γ (PPARγ), involves redistribution of PPARγ binding to form browning-selective PPARγ super-enhancers that drive expression of key browning genes. These include genes encoding transcriptional regulators...

  17. Modulation of chromatin access during adipocyte differentiation

    DEFF Research Database (Denmark)

    Mandrup, Susanne; Hager, Gordon L

    2012-01-01

    Cellular development requires reprogramming of the genome to modulate the gene program of the undifferentiated cell and allow expression of the gene program unique to differentiated cells. A number of key transcription factors involved in this reprogramming of preadipocytes to adipocytes have been...

  18. Effects of Parabens on Adipocyte Differentiation

    Science.gov (United States)

    Zhao, Ling

    2013-01-01

    Parabens are a group of alkyl esters of p-hydroxybenzoic acid that include methylparaben, ethylparaben, propylparaben, butylparaben, and benzylparaben. Paraben esters and their salts are widely used as preservatives in cosmetics, toiletries, food, and pharmaceuticals. Humans are exposed to parabens through the use of such products from dermal contact, ingestion, and inhalation. However, research on the effects of parabens on health is limited, and the effects of parabens on adipogenesis have not been systematically studied. Here, we report that (1) parabens promote adipogenesis (or adipocyte differentiation) in murine 3T3-L1 cells, as revealed by adipocyte morphology, lipid accumulation, and mRNA expression of adipocyte-specific markers; (2) the adipogenic potency of parabens is increased with increasing length of the linear alkyl chain in the following potency ranking order: methyl- parabens, and the structurally related benzoic acid (without the OH group) are inactive in promoting 3T3-L1 adipocyte differentiation; (3) parabens activate glucocorticoid receptor and/or peroxisome proliferator-activated receptor γ in 3T3-L1 preadipocytes; however, no direct binding to, or modulation of, the ligand binding domain of the glucocorticoid receptor by parabens was detected by glucocorticoid receptor competitor assays; and lastly, (4) parabens, butyl- and benzylparaben in particular, also promote adipose conversion of human adipose–derived multipotent stromal cells. Our results suggest that parabens may contribute to obesity epidemic, and the role of parabens in adipogenesis in vivo needs to be examined further. PMID:22956630

  19. [Indications for the combination of pravastatin and fenofibrate according to the type of dyslipidemia].

    Science.gov (United States)

    Núñez-Cortés, Jesús Millán

    2014-07-01

    The combination with fixed doses of pravastatin (40 mg) and fenofibrate (160 mg) offers a therapeutic alternative, especially in the comprehensive approach to mixed hyperlipidemia in patients with high cardiovascular risk of metabolic origin. It also ensures the efficacy and safety as a result of the evidence that supports the clinical benefit of both pravastatin in primary and secondary prevention and fenofibrate in patients with atherogenic dyslipidemia. This combination also has few adverse effects, which are similar in all cases to those produced by the isolated monotherapy of each of the drugs. Consequently, the possible indications for this combination include patients with mixed hyperlipidemia, patients with atherogenic dyslipidemia (increased triglyceride levels, reduced HDL-c levels and moderately increased LDL-c levels), patients with hypertriglyceridemia who need to reduce their LDL-c levels, patients with low HDL syndrome who also require a reduction in LDL-c levels, patients with moderate hypercholesterolemia who require an additional reduction of triglyceride levels and especially patients with high atherogenic metabolic risk who require an overall intervention for each of the lipid fractions. Copyright © 2014 Sociedad Española de Arteriosclerosis y Elsevier España, S.L. All rights reserved.

  20. Hyperlipidemia related to the use of HIV-protease inhibitors: natural history and results of treatment with fenofibrate

    Directory of Open Access Journals (Sweden)

    Bruno Caramelli

    Full Text Available Hyperlipidemia has been frequently recorded as a side effect of treating HIV patients with protease inhibitors (PI. This study was initiated to analyze the modifications on blood lipids in HIV-patients receiving PI and the safety and efficacy of the treatment with fenofibrate. Total (TC and HDL-cholesterol, triglycerides (TG, and CD4+ T-cell counts were measured in 30 HAART-naive patients (Group I before and after PI introduction. In a second phase of the study, the effects of fenofibrate on lipids, CPK, CD4+, and viral load were determined in 13 patients (Group II with elevated TC or TG. In Group I, 60% of the patients showed TC or TG elevations. Average increments of 31% and 146% in TC and TG respectively (p<0.0006 and p<0.0001 were observed. In Group II, fenofibrate treatment was associated with decrements of 6.6% (TC and 45.7% (TG (p=0.07 and 0.0002 and no modifications on CPK, CD4+, and viral load. In conclusion, hyperlipidemia is common during the treatment of HIV with protease inhibitors, and fenofibrate appears to be an effective and safe choice for its treatment.

  1. Hyperlipidemia related to the use of HIV-protease inhibitors: natural history and results of treatment with fenofibrate

    Directory of Open Access Journals (Sweden)

    Caramelli Bruno

    2001-01-01

    Full Text Available Hyperlipidemia has been frequently recorded as a side effect of treating HIV patients with protease inhibitors (PI. This study was initiated to analyze the modifications on blood lipids in HIV-patients receiving PI and the safety and efficacy of the treatment with fenofibrate. Total (TC and HDL-cholesterol, triglycerides (TG, and CD4+ T-cell counts were measured in 30 HAART-naive patients (Group I before and after PI introduction. In a second phase of the study, the effects of fenofibrate on lipids, CPK, CD4+, and viral load were determined in 13 patients (Group II with elevated TC or TG. In Group I, 60% of the patients showed TC or TG elevations. Average increments of 31% and 146% in TC and TG respectively (p<0.0006 and p<0.0001 were observed. In Group II, fenofibrate treatment was associated with decrements of 6.6% (TC and 45.7% (TG (p=0.07 and 0.0002 and no modifications on CPK, CD4+, and viral load. In conclusion, hyperlipidemia is common during the treatment of HIV with protease inhibitors, and fenofibrate appears to be an effective and safe choice for its treatment.

  2. Fenofibrate increases very low density lipoprotein triglyceride production despite reducing plasma triglyceride levels in APOE*3-Leiden.CETP mice

    NARCIS (Netherlands)

    Bijland, S.; Pieterman, E.J.; Maas, A.C.E.; Hoorn, J.W.A. van der; Erk, M.J. van; Klinken, J.B. van; Havekes, L.M.; Dijk, K.W. van; Princen, H.M.G.; Rensen, P.C.N.

    2010-01-01

    The peroxisome proliferator-activated receptor alpha (PPARα) activator fenofibrate efficiently decreases plasma triglycerides (TG), which is generally attributed to enhanced very low density lipoprotein (VLDL)-TG clearance and decreased VLDL-TG production. However, because data on the effect of

  3. Association of gene variants with lipid levels in response to fenofibrate is influenced by metabolic syndrome status

    Science.gov (United States)

    Fenofibrate therapy reduces serum triglycerides (TG) and increases high-density lipoprotein-cholesterol (HDL-C) and thus addresses the atherogenic dyslipidemia associated with metabolic syndrome (MetS). Our hypothesis is that genetic factors contribute to the variability of lipid response to fenofib...

  4. Caffeic Acid Phenethyl Ester Regulates PPAR’s Levels in Stem Cells-Derived Adipocytes

    Directory of Open Access Journals (Sweden)

    Luca Vanella

    2016-01-01

    Full Text Available Hypertrophic obesity inhibits activation of peroxisome proliferators-activated receptor gamma (PPARγ, considered the key mediator of the fully differentiated and insulin sensitive adipocyte phenotype. We examined the effects of Caffeic Acid Phenethyl Ester (Cape, isolated from propolis, a honeybee hive product, on Adipose Stem Cells (ASCs differentiation to the adipocyte lineage. Finally we tested the effects of Cape on insulin-resistant adipocytes. Quantification of Oil Red O-stained cells showed that lipid droplets decreased following Cape treatment as well as radical oxygen species formation. Additionally, exposure of ASC to high glucose levels decreased adiponectin and increased proinflammatory cytokines mRNA levels, which were reversed by Cape-mediated increase of insulin sensitivity. Cape treatment resulted in decreased triglycerides synthesis and increased beta-oxidation. Exposure of ASCs to Lipopolysaccharide (LPS induced a reduction of PPARγ, an increase of IL-6 levels associated with a well-known stimulation of lipolysis; Cape partially attenuated the LPS-mediated effects. These observations reveal the main role of PPARγ in the adipocyte function and during ASC differentiation. As there is now substantial interest in functional food and nutraceutical products, the observed therapeutic value of Cape in insulin-resistance related diseases should be taken into consideration.

  5. Hormonal regulation of rat foetal lipogenesis in brown-adipocyte primary cultures.

    OpenAIRE

    Lorenzo, M; Roncero, C; Fabregat, I; Benito, M

    1988-01-01

    Insulin stimulates lipogenesis by 100% for 5 h by a covalent modulation of acetyl-CoA carboxylase, and by 200% for 24 h by increasing malic enzyme and fatty acid synthase enzymic activities in brown-adipocyte primary cultures. At short times, noradrenaline and isoprenaline decrease lipogenesis. However, phenylephrine and glucagon have no effect. At long times, dexamethasone inhibits lipogenesis. This effect is precluded in the presence of insulin. Progesterone and tri-iodothyronine, alone or ...

  6. Ethyl acetate fraction of Eclipta alba: a potential phytopharmaceutical targeting adipocyte differentiation.

    Science.gov (United States)

    Gupta, Abhishek; Kumar, Ashok; Kumar, Durgesh; Nandan, Shiv; Shankar, Kripa; Varshney, Salil; Rajan, Sujith; Srivastava, Ankita; Gupta, Sanchita; Kanojiya, Sanjeev; Narender, T; Gaikwad, Anil Nilkanth

    2017-12-01

    Natural products have always fascinated mankind for their miraculous properties. Eclipta alba (E. alba), a medicinal herb has long been used in traditional medicine for curing several pathologies. It has been shown to have anti-diabetic effect as well as hepato-protective activity. Here, in order to address metabolic derangements, the study was designed to evaluate the efficacy of E. alba and its fractions in adipogenesis inhibition and dyslipidemia. Of the crude extract and fractions screened, ethyl acetate fraction of E. alba inhibited adipocyte differentiation in 3T3-L1 pre-adipocytes and hMSC derived adipocytes. It inhibited mitotic clonal expansion and caused cell cycle arrest in G1 and S phase as suggested by western blot analysis and flow cytometry. It was also shown to have lipolytic effects. Oral administration of ethyl acetate fraction of E. alba to hamsters unveiled its anti-adipogenic as well as anti-dyslipidemic activity in-vivo. Mass spectrometry analysis of ethyl acetate fraction confirmed the presence of several bioactive components, projecting it as an effective phytopharmaceutical agent. In conclusion, ethyl acetate fraction of E. alba possesses potent anti-adipogenic as well as anti-dyslipidemic activity and could be projected as an herbal formulation towards obesity. Copyright © 2017. Published by Elsevier Masson SAS.

  7. Quercetin, a functional compound of onion peel, remodels white adipocytes to brown-like adipocytes.

    Science.gov (United States)

    Lee, Sang Gil; Parks, John S; Kang, Hye Won

    2017-04-01

    Adipocyte browning is a promising strategy for obesity prevention. Using onion-peel-derived extracts and their bioactive compounds, we demonstrate that onion peel, a by-product of onion, can change the characteristics of white adipocytes to those of brown-like adipocytes in the white adipose tissue of mice and 3T3-L1 cells. The expression of the following brown adipose tissue-specific genes was increased in the retroperitoneal and subcutaneous adipose tissues of 0.5% onion-peel-extract-fed mice: PR domain-containing 16, peroxisome proliferator-activated receptor gamma coactivator 1α, uncoupling protein 1, fibroblast growth factor 21 and cell death-inducing DFFA-like effector. In 3T3-L1 adipocytes, onion peel extract induced the expression of brown adipose tissue-specific genes and increased the expression of carnitine palmitoyltransferase 1α. This effect was supported by decreased lipid levels and multiple small-sized lipid droplets. The ethyl acetate fraction of the onion peel extract that contained the highest proportion of hydrophobic molecules showed the same browning effect in 3T3-L1 adipocytes. A high-performance liquid chromatography analysis further identified quercetin as a functional compound in the browning effect of onion peel. The quercetin-associated browning effect was mediated in part by the activation of AMP-activated protein kinase. In summary, our study provides the first demonstration of the browning effects of onion peel and quercetin using both animal and cell models. This result indicates that onion peel has the potential to remodel the characteristics of white adipocytes to those of brown-like adipocytes. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Control of Adipocyte Differentiation in Different Fat Depots; Implications for Pathophysiology or Therapy

    Directory of Open Access Journals (Sweden)

    Xiuquan eMa

    2015-01-01

    Full Text Available Adipocyte differentiation and its impact on restriction or expansion of particular adipose tissue depots has physiological and pathophysiological significance in view of the different functions of these depots. Brown or beige fat [BAT] expansion can enhance thermogenesis, lipid oxidation, insulin sensitivity and glucose tolerance; conversely expanded visceral fat [VAT] is associated with insulin resistance, low grade inflammation, dyslipidaemia and cardiometabolic risk. The largest depot, subcutaneous white fat [WAT], has important beneficial characteristics including storage of lipid out of harms way and secretion of adipokines, especially leptin and adiponectin, with positive metabolic effects including lipid oxidation, energy utilisation, enhanced insulin action and an anti-inflammatory role. The absence of these functions in lipodystrophies leads to major metabolic disturbances. An ability to expand WAT adipocyte differentiation would seem an important defence mechanism against the detrimental effects of energy excess and limit harmful accumulation of lipid in ectopic sites, such as liver and muscle.Adipocyte differentiation involves a transcriptional cascade with PPARg being most important in WAT but less so in VAT, with increased angiogenesis also critical. The transcription factor, Islet1, is fairly specific to VAT and in vitro inhibits adipocyte differentiation. The physiological importance of Islet1 requires further study. Basic control of differentiation is similar in BAT but important differences include the effect of PGC-1a on mitochondrial biosynthesis and upregulation of UCP1; also PRDM16 plays a pivotal role in expression of the BAT phenotype.Modulation of the capacity or function of these different adipose tissue depots, by altering adipocyte differentiation or other means, holds promise for interventions that can be helpful in human disease, particularly cardiometabolic disorders associated with the world wide explosion of

  9. Directing visceral white adipocyte precursors to a thermogenic adipocyte fate improves insulin sensitivity in obese mice.

    Science.gov (United States)

    Hepler, Chelsea; Shao, Mengle; Xia, Jonathan Y; Ghaben, Alexandra L; Pearson, Mackenzie J; Vishvanath, Lavanya; Sharma, Ankit X; Morley, Thomas S; Holland, William L; Gupta, Rana K

    2017-07-19

    Visceral adiposity confers significant risk for developing metabolic disease in obesity whereas preferential expansion of subcutaneous white adipose tissue (WAT) appears protective. Unlike subcutaneous WAT, visceral WAT is resistant to adopting a protective thermogenic phenotype characterized by the accumulation of Ucp1 + beige/BRITE adipocytes (termed 'browning'). In this study, we investigated the physiological consequences of browning murine visceral WAT by selective genetic ablation of Zfp423 , a transcriptional suppressor of the adipocyte thermogenic program. Zfp423 deletion in fetal visceral adipose precursors ( Zfp423 l oxP/loxP ; Wt1-Cre ), or adult visceral white adipose precursors ( Pdgfrb rtTA ; TRE-Cre; Zfp423 l oxP/loxP ), results in the accumulation of beige-like thermogenic adipocytes within multiple visceral adipose depots. Thermogenic visceral WAT improves cold tolerance and prevents and reverses insulin resistance in obesity. These data indicate that beneficial visceral WAT browning can be engineered by directing visceral white adipocyte precursors to a thermogenic adipocyte fate, and suggest a novel strategy to combat insulin resistance in obesity.

  10. Adipocyte CREB promotes insulin resistance in obesity.

    Science.gov (United States)

    Qi, Ling; Saberi, Maziyar; Zmuda, Erik; Wang, Yiguo; Altarejos, Judith; Zhang, Xinmin; Dentin, Renaud; Hedrick, Susie; Bandyopadhyay, Gautam; Hai, Tsonwin; Olefsky, Jerry; Montminy, Marc

    2009-03-01

    Increases in adiposity trigger metabolic and inflammatory changes that interfere with insulin action in peripheral tissues, culminating in beta cell failure and overt diabetes. We found that the cAMP Response Element Binding protein (CREB) is activated in adipose cells under obese conditions, where it promotes insulin resistance by triggering expression of the transcriptional repressor ATF3 and thereby downregulating expression of the adipokine hormone adiponectin as well as the insulin-sensitive glucose transporter 4 (GLUT4). Transgenic mice expressing a dominant-negative CREB transgene in adipocytes displayed increased whole-body insulin sensitivity in the contexts of diet-induced and genetic obesity, and they were protected from the development of hepatic steatosis and adipose tissue inflammation. These results indicate that adipocyte CREB provides an early signal in the progression to type 2 diabetes.

  11. High density lipoprotein structural changes and drug response in lipidomic profiles following the long-term fenofibrate therapy in the FIELD substudy.

    Directory of Open Access Journals (Sweden)

    Laxman Yetukuri

    Full Text Available In a recent FIELD study the fenofibrate therapy surprisingly failed to achieve significant benefit over placebo in the primary endpoint of coronary heart disease events. Increased levels of atherogenic homocysteine were observed in some patients assigned to fenofibrate therapy but the molecular mechanisms behind this are poorly understood. Herein we investigated HDL lipidomic profiles associated with fenofibrate treatment and the drug-induced Hcy levels in the FIELD substudy. We found that fenofibrate leads to complex HDL compositional changes including increased apoA-II, diminishment of lysophosphatidylcholines and increase of sphingomyelins. Ethanolamine plasmalogens were diminished only in a subgroup of fenofibrate-treated patients with elevated homocysteine levels. Finally we performed molecular dynamics simulations to qualitatively reconstitute HDL particles in silico. We found that increased number of apoA-II excludes neutral lipids from HDL surface and apoA-II is more deeply buried in the lipid matrix than apoA-I. In conclusion, a detailed molecular characterization of HDL may provide surrogates for predictors of drug response and thus help identify the patients who might benefit from fenofibrate treatment.

  12. Phytic acid and myo-inositol support adipocyte differentiation and improve insulin sensitivity in 3T3-L1 cells.

    Science.gov (United States)

    Kim, Jin Nam; Han, Sung Nim; Kim, Hye-Kyeong

    2014-08-01

    Phytic acid, also known as myo-inositol hexaphosphate, has been shown to lower blood glucose levels and to improve insulin sensitivity in rodents. We investigated the effects of phytic acid and myo-inositol on differentiation, insulin-stimulated glucose uptake, and lipolysis of adipocytes to test the hypothesis that the antidiabetic properties of phytic acid and myo-inositol are mediated directly through adipocytes. 3T3-L1 cells were treated with 10, 50, or 200 μmol/L of phytic acid or myo-inositol. Oil Red O staining and an intracellular triacylglycerol assay were used to determine lipid accumulation during adipocyte differentiation. Immunoblotting and real-time polymerase chain reaction (PCR) were performed to evaluate expression of transcription factors, a target protein, and insulin signaling molecules. Phytic acid and myo-inositol exposures increased lipid accumulation in a dose-dependent manner (P inositol (P inositol treatments (P inositol treatments. In fully differentiated adipocytes, phytic acid and myo-inositol reduced basal lipolysis dose dependently (P inositol increase insulin sensitivity in adipocytes by increasing lipid storage capacity, improving glucose uptake, and inhibiting lipolysis. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Protein Carbonylation and Adipocyte Mitochondrial Function*

    Science.gov (United States)

    Curtis, Jessica M.; Hahn, Wendy S.; Stone, Matthew D.; Inda, Jacob J.; Droullard, David J.; Kuzmicic, Jovan P.; Donoghue, Margaret A.; Long, Eric K.; Armien, Anibal G.; Lavandero, Sergio; Arriaga, Edgar; Griffin, Timothy J.; Bernlohr, David A.

    2012-01-01

    Carbonylation is the covalent, non-reversible modification of the side chains of cysteine, histidine, and lysine residues by lipid peroxidation end products such as 4-hydroxy- and 4-oxononenal. In adipose tissue the effects of such modifications are associated with increased oxidative stress and metabolic dysregulation centered on mitochondrial energy metabolism. To address the role of protein carbonylation in the pathogenesis of mitochondrial dysfunction, quantitative proteomics was employed to identify specific targets of carbonylation in GSTA4-silenced or overexpressing 3T3-L1 adipocytes. GSTA4-silenced adipocytes displayed elevated carbonylation of several key mitochondrial proteins including the phosphate carrier protein, NADH dehydrogenase 1α subcomplexes 2 and 3, translocase of inner mitochondrial membrane 50, and valyl-tRNA synthetase. Elevated protein carbonylation is accompanied by diminished complex I activity, impaired respiration, increased superoxide production, and a reduction in membrane potential without changes in mitochondrial number, area, or density. Silencing of the phosphate carrier or NADH dehydrogenase 1α subcomplexes 2 or 3 in 3T3-L1 cells results in decreased basal and maximal respiration. These results suggest that protein carbonylation plays a major instigating role in cytokine-dependent mitochondrial dysfunction and may be linked to the development of insulin resistance in the adipocyte. PMID:22822087

  14. Protein carbonylation and adipocyte mitochondrial function.

    Science.gov (United States)

    Curtis, Jessica M; Hahn, Wendy S; Stone, Matthew D; Inda, Jacob J; Droullard, David J; Kuzmicic, Jovan P; Donoghue, Margaret A; Long, Eric K; Armien, Anibal G; Lavandero, Sergio; Arriaga, Edgar; Griffin, Timothy J; Bernlohr, David A

    2012-09-21

    Carbonylation is the covalent, non-reversible modification of the side chains of cysteine, histidine, and lysine residues by lipid peroxidation end products such as 4-hydroxy- and 4-oxononenal. In adipose tissue the effects of such modifications are associated with increased oxidative stress and metabolic dysregulation centered on mitochondrial energy metabolism. To address the role of protein carbonylation in the pathogenesis of mitochondrial dysfunction, quantitative proteomics was employed to identify specific targets of carbonylation in GSTA4-silenced or overexpressing 3T3-L1 adipocytes. GSTA4-silenced adipocytes displayed elevated carbonylation of several key mitochondrial proteins including the phosphate carrier protein, NADH dehydrogenase 1α subcomplexes 2 and 3, translocase of inner mitochondrial membrane 50, and valyl-tRNA synthetase. Elevated protein carbonylation is accompanied by diminished complex I activity, impaired respiration, increased superoxide production, and a reduction in membrane potential without changes in mitochondrial number, area, or density. Silencing of the phosphate carrier or NADH dehydrogenase 1α subcomplexes 2 or 3 in 3T3-L1 cells results in decreased basal and maximal respiration. These results suggest that protein carbonylation plays a major instigating role in cytokine-dependent mitochondrial dysfunction and may be linked to the development of insulin resistance in the adipocyte.

  15. Beyond obesity - thermogenic adipocytes and cardiometabolic health.

    Science.gov (United States)

    Aldiss, Peter; Dellschaft, Neele; Sacks, Harold; Budge, Helen; Symonds, Michael E

    2017-05-26

    The global prevalence of obesity and related cardiometabolic disease continues to increase through the 21st century. Whilst multi-factorial, obesity is ultimately caused by chronic caloric excess. However, despite numerous interventions focussing on reducing caloric intake these either fail or only elicit short-term changes in body mass. There is now a focus on increasing energy expenditure instead which has stemmed from the recent 're-discovery' of cold-activated brown adipose tissue (BAT) in adult humans and inducible 'beige' adipocytes. Through the unique mitochondrial uncoupling protein 1 (UCP1), these thermogenic adipocytes are capable of combusting large amounts of chemical energy as heat and in animal models can prevent obesity and cardiometabolic disease. At present, human data does not point to a role for thermogenic adipocytes in regulating body weight or fat mass but points to a pivotal role in regulating metabolic health by improving insulin resistance as well as glucose and lipid homeostasis. This review will therefore focus on the metabolic benefits of BAT activation and the mechanisms and signalling pathways by which these could occur including improvements in insulin signalling in peripheral tissues, systemic lipid and cholesterol metabolism and cardiac and vascular function.

  16. Restricting glycolysis impairs brown adipocyte glucose and oxygen consumption

    DEFF Research Database (Denmark)

    Winther, Sally; Isidor, Marie S; Basse, Astrid L

    2018-01-01

    )-stimulated respiration was fueled mainly by fatty acids, with a significant contribution from glucose oxidation. Knockdown of glucose transporters in brown adipocytes not only impaired ISO-stimulated glycolytic flux but also oxygen consumption. Diminishing glycolytic flux by knockdown of the first and final enzyme......During thermogenic activation, brown adipocytes take up large amounts of glucose. In addition, cold stimulation leads to an upregulation of glycolytic enzymes. Here we have investigated the importance of glycolysis for brown adipocyte glucose consumption and thermogenesis. Using si......RNA-mediated knockdown in mature adipocytes, we explored the effect of glucose transporters and glycolytic enzymes on brown adipocyte functions such as consumption of glucose and oxygen. Basal oxygen consumption in brown adipocytes was equally dependent on glucose and fatty acid oxidation, whereas isoproterenol (ISO...

  17. Intradermal adipocytes mediate fibroblast recruitment during skin wound healing

    Science.gov (United States)

    Schmidt, Barbara A.; Horsley, Valerie

    2013-01-01

    Acute wound healing in the skin involves the communication of multiple cell types to coordinate keratinocyte and fibroblast proliferation and migration for epidermal and dermal repair. Many studies have focused on the interplay between hematopoietic cells, keratinocytes and fibroblasts during skin wound healing, yet the possible roles for other cell types within the skin, such as intradermal adipocytes, have not been investigated during this process. Here, we identify that adipocyte lineage cells are activated and function during acute skin wound healing. We find that adipocyte precursor cells proliferate and mature adipocytes repopulate skin wounds following inflammation and in parallel with fibroblast migration. Functional analysis of mice with defects in adipogenesis demonstrates that adipocytes are necessary for fibroblast recruitment and dermal reconstruction. These data implicate adipocytes as a key component of the intercellular communication that mediates fibroblast function during skin wound healing. PMID:23482487

  18. Cadmium modulates adipocyte functions in metallothionein-null mice

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Takashige; Nishiyama, Kaori; Kadota, Yoshito; Sato, Masao; Inoue, Masahisa; Suzuki, Shinya, E-mail: suzukis@ph.bunri-u.ac.jp

    2013-11-01

    Our previous study has demonstrated that exposure to cadmium (Cd), a toxic heavy metal, causes a reduction of adipocyte size and the modulation of adipokine expression. To further investigate the significance of the Cd action, we studied the effect of Cd on the white adipose tissue (WAT) of metallothionein null (MT{sup −/−}) mice, which cannot form atoxic Cd–MT complexes and are used for evaluating Cd as free ions, and wild type (MT{sup +/+}) mice. Cd administration more significantly reduced the adipocyte size of MT{sup −/−} mice than that of MT{sup +/+} mice. Cd exposure also induced macrophage recruitment to WAT with an increase in the expression level of Ccl2 (MCP-1) in the MT{sup −/−} mice. The in vitro exposure of Cd to adipocytes induce triglyceride release into culture medium, decrease in the expression levels of genes involved in fatty acid synthesis and lipid hydrolysis at 24 h, and at 48 h increase in phosphorylation of the lipid-droplet-associated protein perilipin, which facilitates the degradation of stored lipids in adipocytes. Therefore, the reduction in adipocyte size by Cd may arise from an imbalance between lipid synthesis and lipolysis. In addition, the expression levels of leptin, adiponectin and resistin decreased in adipocytes. Taken together, exposure to Cd may induce unusually small adipocytes and modulate the expression of adipokines differently from the case of physiologically small adipocytes, and may accelerate the risk of developing insulin resistance and type 2 diabetes. - Highlights: • Cd causes a marked reduction in adipocyte size in MT-null mice. • Cd enhances macrophage migration into adipose tissue and disrupt adipokine secretion. • MT gene alleviates Cd-induced adipocyte dysfunctions. • Cd enhances the degradation of stored lipids in adipocytes, mediated by perilipin. • Cd induces unusually small adipocytes and the abnormal expression of adipokines.

  19. The tumor suppressors pRB and p53 as regulators of adipocyte differentiation and function

    DEFF Research Database (Denmark)

    Hallenborg, Philip; Feddersen, Søren; Madsen, Lise

    2009-01-01

    BACKGROUND: The retinoblastoma protein (pRB) and p53 are crucial members of regulatory networks controlling the cell cycle and apoptosis, and a hallmark of virtually all cancers is dysregulation of expression or function of pRB or p53. Although they are best known for their role in cancer...... development, it is now evident that both are implicated in metabolism and cellular development. OBJECTIVE/METHODS: To review the role of pRB and p53 in adipocyte differentiation and function emphasizing that pRB and p53, via their effects on adipocyte development and function, play a role in the regulation...... of energy metabolism and homeostasis. RESULTS/CONCLUSIONS: pRB is required for adipose conversion and also involved in determining its mitochondrial capacity. p53 inhibits adipogenesis and results suggest that it is involved in maintaining function of adipose tissue....

  20. Selective effect of phosphatidylcholine on the lysis of adipocytes.

    Directory of Open Access Journals (Sweden)

    Ji-Young Kim

    Full Text Available Obesity, a serious health risk factor, is often associated with depression and negatively affects many aspects of life. Injection of a formula comprising phosphatidylcholine (PPC and deoxycholate (DC has emerged as an alternative to liposuction in the reduction of local fat deposits. However, the formula component mainly responsible for this effect and the mechanism behind the actions of the components with respect to fat reduction are unknown. Here, we investigate the specific effects of PPC and DC on adipocyte viability. When exposed to PPC or DC, 3T3L1 preadipocytes and differentiated adipocytes showed dose dependent decrease in cell viability. Interestingly, while DC mediated cell death was non-specific to both preadipocytes and adipocytes, PPC specifically induced a decrease in mature adipocyte viability, but had less effect on preadipocytes. Injection of PPC and DC into inguinal fat pads caused reduction in size. PPC injections preferentially decreased gene expression in mature adipocytes, while a strong inflammatory response was elicited by DC injection. In line with the decreased adipocyte viability, exposure of differentiated adipocytes to PPC resulted in triglyceride release, with a minimal effect on free fatty acids release, suggesting that its fat-reducing effect mediated mainly through the induction of adipocyte cell death rather than lipolysis. Taken together, it appears that PPC specifically affects adipocytes, and has less effect on preadipocyte viability. It can therefore be a promising agent to selectively reduce adipose tissue mass.

  1. Effects of GSK3 inhibitors on in vitro expansion and differentiation of human adipose-derived stem cells into adipocytes

    Directory of Open Access Journals (Sweden)

    Peraldi Pascal

    2008-02-01

    Full Text Available Abstract Background Multipotent stem cells exist within adipose tissue throughout life. An abnormal recruitment of these adipose precursor cells could participate to hyperplasia of adipose tissue observed in severe obesity or to hypoplasia of adipose tissue observed in lipodystrophy. Therefore, pharmacological molecules that control the pool of stem cells in adipose tissue are of great interest. Glycogen Synthase Kinase (GSK 3 has been previously described as involved in differentiation of preadipose cells and might be a potential therapeutic target to modulate proliferation and differentiation of adipocyte precursors. However, the impact of GSK3 inhibition on human adipose-derived stem cells remained to be investigated. The aim of this study was to investigate GSK3 as a possible target for pharmacological inhibition of stem cell adipogenesis. To reach this goal, we studied the effects of pharmacological inhibitors of GSK3, i.e. lithium chloride (LiCl and BIO on proliferation and adipocyte differentiation of multipotent stem cells derived from human adipose tissue. Results Our results showed that GSK3 inhibitors inhibited proliferation and clonogenicity of human stem cells, strongly suggesting that GSK3 inhibitors could be potent regulators of the pool of adipocyte precursors in adipose tissue. The impact of GSK3 inhibition on differentiation of hMADS cells was also investigated. Adipogenic and osteogenic differentiations were inhibited upon hMADS treatment with BIO. Whereas a chronic treatment was required to inhibit osteogenesis, a treatment that was strictly restricted to the early step of differentiation was sufficient to inhibit adipogenesis. Conclusion These results demonstrated the feasibility of a pharmacological approach to regulate adipose-derived stem cell function and that GSK3 could represent a potential target for controlling adipocyte precursor pool under conditions where fat tissue formation is impaired.

  2. Effect of fenofibrate on uric acid and gout in type 2 diabetes: a post-hoc analysis of the randomised, controlled FIELD study.

    Science.gov (United States)

    Waldman, Boris; Ansquer, Jean-Claude; Sullivan, David R; Jenkins, Alicia J; McGill, Neil; Buizen, Luke; Davis, Timothy M E; Best, James D; Li, Liping; Feher, Michael D; Foucher, Christelle; Kesaniemi, Y Antero; Flack, Jeffrey; d'Emden, Michael C; Scott, Russell S; Hedley, John; Gebski, Val; Keech, Anthony C

    2018-04-01

    Gout is a painful disorder and is common in type 2 diabetes. Fenofibrate lowers uric acid and reduces gout attacks in small, short-term studies. Whether fenofibrate produces sustained reductions in uric acid and gout attacks is unknown. In the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) trial, participants aged 50-75 years with type 2 diabetes were randomly assigned to receive either co-micronised fenofibrate 200 mg once per day or matching placebo for a median of 5 years follow-up. We did a post-hoc analysis of recorded on-study gout attacks and plasma uric acid concentrations according to treatment allocation. The outcomes of this analysis were change in uric acid concentrations and risk of on-study gout attacks. The FIELD study is registered with ISRCTN, number ISRCTN64783481. Between Feb 23, 1998, and Nov 3, 2000, 9795 patients were randomly assigned to fenofibrate (n=4895) or placebo (n=4900) in the FIELD study. Uric acid concentrations fell by 20·2% (95% CI 19·9-20·5) during the 6-week active fenofibrate run-in period immediately pre-randomisation (a reduction of 0·06 mmol/L or 1 mg/dL) and remained -20·1% (18·5-21·7, puric acid concentration higher than 0·36 mmol/L and 13·9% in those with baseline uric acid concentration higher than 0·42 mmol/L, compared with 3·4% and 5·7%, respectively, in the fenofibrate group. Risk reductions were similar among men and women and those with dyslipidaemia, on diuretics, and with elevated uric acid concentrations. For participants with elevated baseline uric acid concentrations despite taking allopurinol at study entry, there was no heterogeneity of the treatment effect of fenofibrate on gout risk. Taking account of all gout events, fenofibrate treatment halved the risk (HR 0·48, 95% CI 0·37-0·60; puric acid concentrations by 20%, and almost halved first on-study gout events over 5 years of treatment. Fenofibrate could be a useful adjunct for preventing gout in diabetes. None. Copyright

  3. Effect of Ceolus KG-802 on the dissolution rate of fenofibrate liquisolid tablets: Preformulation and formulation development studies.

    Science.gov (United States)

    Karmarkar, A B

    2010-12-01

    The purpose of the present research was to study the effects of Ceolus KG-802 on the dissolution behavior of fenofibrate liquisolid tablets. The fenofibrate liquisolid tablets were formulated using the mathematical model described by Spireas et al. In the present research, Ceolus KG-802, a different form of microcrystalline cellulose (PH 102 grade), was used as a carrier material. The developed formulations were subjected to preformulation studies such as differential scanning calorimetry, X-ray powder diffraction, and determination of flow properties. The liquisolid tablets prepared were studied for their in vitro dissolution and compared to liquisolid tablets prepared using Avicel PH 102. The in vitro dissolution profiles of liquisolid tablets prepared using Ceolus KG-802 indicated slower dissolution than those of liquisolid tablets prepared using Avicel PH 102, which was a subject of earlier studies. This might be due to the particle size, shape, and characteristic properties of Ceolus KG-802.

  4. Anti-obesity effects of Arctii Fructus (Arctium lappa) in white/brown adipocytes and high-fat diet-induced obese mice.

    Science.gov (United States)

    Han, Yo-Han; Kee, Ji-Ye; Kim, Dae-Seung; Park, Jinbong; Jeong, Mi-Young; Mun, Jung-Geon; Park, Sung-Joo; Lee, Jong-Hyun; Um, Jae-Young; Hong, Seung-Heon

    2016-12-07

    Arctii Fructus is traditionally used in oriental pharmacies as an anti-inflammatory medicine. Although several studies have shown its anti-inflammatory effects, there have been no reports on its use in obesity related studies. In this study, the anti-obesity effect of Arctii Fructus was investigated in high-fat diet (HFD)-induced obese mice, and the effect was confirmed in white and primary cultured brown adipocytes. Arctii Fructus inhibited weight gain and reduced the mass of white adipose tissue in HFD-induced obese mice. Serum levels of triglyceride and LDL-cholesterol were reduced, and HDL-cholesterol was increased in the Arctii Fructus treated group. In 3T3-L1 cells, a water extract (WAF) and 70% EtOH extract (EtAF) of Arctii Fructus significantly inhibited adipogenesis and suppressed the expression of proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha. In particular, EtAF activated the phosphorylation of AMP-activated protein kinase. On the other hand, uncoupling protein 1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha, known as brown adipocytes specific genes, were increased in primary cultured brown adipocytes by WAF and EtAF. This study shows that Arctii Fructus prevents the development of obesity through the inhibition of white adipocyte differentiation and activation of brown adipocyte differentiation which suggests that Arctii Fructus could be an effective therapeutic for treating or preventing obesity.

  5. Investigating the correlation between in vivo absorption and in vitro release of fenofibrate from lipid matrix particles in biorelevant medium.

    Science.gov (United States)

    Borkar, Nrupa; Xia, Dengning; Holm, René; Gan, Yong; Müllertz, Anette; Yang, Mingshi; Mu, Huiling

    2014-01-23

    Lipid matrix particles (LMP) may be used as better carriers for poorly water-soluble drugs than liquid lipid carriers because of reduced drug mobilization in the formulations. However, the digestion process of solid lipid particles and their effect on the absorption of poorly water-soluble drugs are not fully understood. This study aimed at investigating the effect of particle size of LMP on drug release in vitro as well as absorption in vivo in order to get a better understanding on the effect of degradation of lipid particles on drug solubilisation and absorption. Fenofibrate, a model poorly water-soluble drug, was incorporated into LMP in this study using probe ultrasound sonication. The resultant LMP were characterised in terms of particle size, size distribution, zeta potential, entrapment efficiency, in vitro lipolysis and in vivo absorption in rat model. LMP of three different particle sizes i.e. approximately 100 nm, 400 nm, and 10 μm (microparticles) were produced with high entrapment efficiencies. The in vitro lipolysis study showed that the recovery of fenofibrate in the aqueous phase for 100 nm and 400 nm LMP was significantly higher (pmicroparticles>control. In summary, the present study demonstrated the particle size dependence of bioavailability of fenofibrate loaded LMP in rat model which correlates well with the in vitro drug release performed in the biorelevant medium. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. High-performance liquid chromatography and derivative spectrophotometry for simultaneous determination of pravastatin and fenofibrate in the dosage form

    Directory of Open Access Journals (Sweden)

    Hefnawy Mohamed M.

    2014-12-01

    Full Text Available High performance liquid chromatography (HPLC and second-order derivative spectrophotometry have been used for simultaneous determination of pravastatin (PS and fenofibrate (FF in pharmaceutical formulations. HPLC separation was performed on a phenyl HYPERSIL C18 column (125 mm × 4.6 mm i.d., 5 μm particle diameter in the isocratic mode using a mobile phase acetonitrile/0.1 % diethyl amine (50:50, V/V, pH 4.5 pumped at a flow rate of 1.0 mL min-1. Measurement was made at 240 nm. Both drugs were well resolved on the stationary phase, with retention times of 2.15 and 5.79 min for PS and FF, respectively. Calibration curves were linear (R = 0.999 for PS and 0.996 for FF in the concentration range of 5-50 and 20-200 µg mL-1 for PS and FF, respectively. Pravastatin and fenofibrate were quantitated in combined preparations also using the second-order derivative response at 237.6 and 295.1 nm for PS and FF, respectively. Calibration curves were linear, with the correlation coefficient R = 0.999 for pravastatin and fenofibrate, in the concentration range of 5-20 and 3-20 µg mL-1 for PS and FF, respectively. Both methods were fully validated and compared, the results confirmed that they were highly suitable for their intended purpose.

  7. Gastrointestinal behavior of nano- and microsized fenofibrate: In vivo evaluation in man and in vitro simulation by assessment of the permeation potential.

    Science.gov (United States)

    Hens, Bart; Brouwers, Joachim; Corsetti, Maura; Augustijns, Patrick

    2015-09-18

    The purpose of this study was (i) to evaluate the gastrointestinal behavior of micro- and nanosized fenofibrate in humans and (ii) to develop a simple yet qualitatively predictive in vitro setup that simulates the observed absorption-determining factors. Commercially available micro- and nanoparticles of fenofibrate (Lipanthyl® and Lipanthylnano®, respectively) were administered orally to five healthy volunteers in fasting and postprandial conditions. Intraluminal and systemic drug concentrations were determined as reference data for the development of a predictive in vitro setup. To capture the observed solubility/permeability interplay, in vitro dissolution testing was performed in the presence of a permeation bag with sink conditions. In fasting conditions, intake of nanosized fenofibrate generated increased duodenal concentrations compared to microsized fenofibrate, which was reflected in an improved systemic exposure. In postprandial conditions, duodenal concentrations were greatly enhanced for both formulations, however without an accompanying increase in systemic exposure. It appeared that micellar encapsulation of the highly lipohilic fenofibrate limited its potential to permeate from fed state intestinal fluids. To capture these in vivo observations in an in vitro setup, classic dissolution testing was combined with permeation assessment into a permeation bag with sink conditions. In case of fasting conditions, the dissolution/permeation approach allowed for an improved discriminative power between micro- and nanosized fenofibrate by better simulating the dynamic interplay of dissolution and absorption. In case of postprandial conditions, the observed solubility-permeability interplay could be simulated using the dissolution/permeation approach in combination with biorelevant media (FeSSGFFortimel and FeSSIF-V2) to mimic micellar entrapment and reduced permeation potential of fenofibrate. For the first time, reduced permeation of a lipophilic drug

  8. Grape seed proanthocyanidin supplementation reduces adipocyte size and increases adipocyte number in obese rats.

    Science.gov (United States)

    Pascual-Serrano, A; Arola-Arnal, A; Suárez-García, S; Bravo, F I; Suárez, M; Arola, L; Bladé, C

    2017-08-01

    White adipose tissue (WAT) expands through hypertrophy (increased adipocyte size) and/or hyperplasia (increased adipocyte number). Hypertrophy has been associated with insulin resistance and dyslipidemia independently of body composition and fat distribution. In contrast, hyperplasia protects against metabolic alterations. Proanthocyanidins, which are the most abundant flavonoids in the human diet, improve metabolic disturbances associated with diet-induced obesity without reducing body weight or adiposity. The aim of this study was to determine whether grape seed proanthocyanidin extract (GSPE) can modulate WAT expandability. Because GSPE also contains gallic acid, we also studied the capacity of gallic acid to remodel WAT. Male Wistar rats were fed a standard chow diet (n=6) or a cafeteria diet (CAF) for 11 weeks. After 8 weeks, the CAF-fed animals were supplemented with 25 mg GSPE/kg body weight (n=6), 7 mg gallic acid/kg body weight (n=6) or the vehicle (n=6) for 3 weeks. Histological analyses were performed in the retroperitoneal (rWAT) and inguinal (iWAT) WAT to determine adipocyte size and number. Specific markers for adipogenesis and WAT functionality were analysed in rWAT using quantitative RT-PCR. GSPE or gallic acid supplementation did not reduce weight gain or reverse and adiposity. However, GSPE reduced adipocyte size significantly in rWAT and moderately in iWAT and tripled the adipocyte number in rWAT. Gallic acid slightly reduced adipocyte size in rWAT and iWAT and doubled the adipocyte number in both WATs. In accordance with this adipogenic activity, Pref-1 and PPARγ tended to be overexpressed in rWAT of rats supplemented with GSPE. Moreover, GSPE supplementation increased Plin1 and Fabp4 expression and restored adiponectin expression completely, indicating a better functionality of visceral WAT. GSPE supplementation has anti-hypertrophic and hyperplasic activities in rats with established obesity, mainly in visceral WAT inducing a healthier

  9. Retroendocytosis of insulin in rat adipocytes

    International Nuclear Information System (INIS)

    Levy, J.R.; Olefsky, J.M.

    1986-01-01

    A variety of ligands internalized by receptor-mediated endocytosis follow a short circuit pathway that does not lead to degradation but results in rapid exocytosis of intact ligand, a process termed retroendocytosis. We studied the time course of [ 125 I]iodoinsulin processing and retroendocytosis after internalization in isolated rat adipocytes. After steady state binding and internalization, surface receptor-bound insulin was removed by exposing cells to a low pH at low temperatures. The cells containing internalized [ 125 I]iodoinsulin were reincubated in fresh medium; subsequently, the radioactivity remaining within the cells and released into the medium were analyzed at various times by trichloroacetic acid (TCA) precipitation, Sephadex G-50 gel filtration, and reverse phase HPLC. Cell-associated radioactivity progressively decreased after reincubation in 37 C buffer, with 50% released in 9 min and 85% by 45 min. In the media, TCA-precipitable material appeared quickly, with a t1/2 of 2 min, and plateaued by 10 min. TCA-soluble material was released continually throughout the 45-min period. The release of both TCA-precipitable and TCA-soluble material was temperature and energy dependent. Sephadex G-50 chromatography demonstrated the loss of insulin from the intracellular pool and its appearance in the medium with a time course similar to that of TCA-precipitable material. Reverse phase HPLC demonstrated that the intracellular and medium radioactivity eluting in peak II (insulin peak) on Sephadex G-50 was composed of both intact insulin and intermediates. After the internalization of insulin, rat adipocytes release not only small mol wt degradation products of insulin, but also insulin intermediates and intact insulin. The rate of retroendocytosis reported here is almost identical to the rate of insulin receptor recycling in rat adipocytes

  10. Curcumin attenuates lipolysis stimulated by tumor necrosis factor-α or isoproterenol in 3T3-L1 adipocytes.

    Science.gov (United States)

    Xie, Xiao-yun; Kong, Po-Ren; Wu, Jin-feng; Li, Ying; Li, Yan-xiang

    2012-12-15

    Curcumin, an active component derived from dietary spice turmeric (Curcuma longa), has been demonstrated antihyperglycemic, antiinflammatory and hypocholesterolemic activities in obesity and diabetes. These effects are associated with decreased level of circulating free fatty acids (FFA), however the mechanism has not yet been elucidated. The flux of FFA and glycerol from adipose tissue to the blood stream primarily depends on the lipolysis of triacylglycerols in the adipocytes. Adipocyte lipolysis is physiologically stimulated by catecholamine hormones. Tumor necrosis factor-α (TNFα) stimulates chronic lipolysis in obesity and type 2 diabetes. In this study, we examined the role of curcumin in inhibiting lipolytic action upon various stimulations in 3T3-L1 adipocytes. Glycerol release from TNFα or isoproterenol-stimulated 3T3-L1 adipocytes in the absence or presence of curcumin was determined using a colorimetric assay (GPO-Trinder). Western blotting was used to investigate the TNFα-induced phosphorylation of MAPK and perilipin expression. Fatcake and cytosolic fractions were prepared to examine the isoproterenol-stimulated hormone-sensitive lipase translocation. Treatment with curcumin attenuated TNFα-mediated lipolysis by suppressing phosphorylation of extracellular signal-related kinase 1/2 (ERK1/2) and reversing the downregulation of perilipin protein in TNFα-stimulated adipocytes (p<0.05). The acute lipolytic response to adrenergic stimulation of isoproterenol was also restricted by curcumin (10-20 μM, p<0.05), which was compatible with reduced perilipin phosphorylation(29%, p<0.05) and hormone-sensitive lipase translocation(20%, p<0.05). This study provides evidence that curcumin acts on adipocytes to suppress the lipolysis response to TNFα and catecholamines. The antilipolytic effect could be a cellular basis for curcumin decreasing plasma FFA levels and improving insulin sensitivity. Copyright © 2012 Elsevier GmbH. All rights reserved.

  11. Transdifferentiation properties of adipocytes in the adipose organ.

    Science.gov (United States)

    Cinti, Saverio

    2009-11-01

    Mammals have two types of adipocytes, white and brown, but their anatomy and physiology is different. White adipocytes store lipids, and brown adipocytes burn them to produce heat. Previous descriptions implied their localization in distinct sites, but we demonstrated that they are mixed in many depots, raising the concept of adipose organ. We explain the reason for their cohabitation with the hypothesis of reversible physiological transdifferentiation; they are able to convert one into each other. If needed, the brown component of the organ could increase at the expense of the white component and vice versa. This plasticity is important because the brown phenotype of the organ associates with resistance to obesity and related disorders. Another example of physiological transdifferetiation of adipocytes is offered by the mammary gland; the pregnancy hormonal stimuli seems to trigger a reversible transdifferentiation of adipocytes into milk-secreting epithelial glands. The obese adipose organ is infiltrated by macrophages inducing chronic inflamation that is widely considered as a causative factor for insulin resistance. We showed that the vast majority of macrophages infiltrating the obese organ are arranged around dead adipocytes, forming characteristic crown-like structures. We recently found that visceral fat is more infiltrated than the subcutaneous fat despite a smaller size of visceral adipocytes. This suggests a different susceptibility of visceral and subcutaneous adipocytes to death, raising the concept of smaller critical death size that could be important to explain the key role of visceral fat for the metabolic disorders associated with obesity.

  12. Metabolic cooperativity between epithelial cells and adipocytes of mice

    International Nuclear Information System (INIS)

    Bartley, J.C.; Emerman, J.T.; Bissell, M.J.

    1981-01-01

    We have demonstrated that glycogen and lipid synthesis in adipocytes is modulated by the lactational state and that this modulation in mammary adipocytes requires the presence of the adjacent epithelial cells. Glycogen and lipid synthesis from [ 14 C]glucose was measured in mammary fat pads cleared of epithelium, in abdominal fat pads, and in adipocytes from both sources and from intact mammary gland of mature virgin, pregnant, and lactating mice. Accumulation of glycogen, the activity of glycogen synthase, and the lipogenic rate in abdominal and mammary adipocytes remained high during pregnancy but decreased to insignificant levels by early lactation. The depressant effects of lactation were observed solely in those mammary adipocytes isolated from intact glands. The presence of mammary epithelial cells was also required to effect the stimulated lipogenesis in mammary adipocytes during pregnancy. We conclude that the metabolic activity of adipocytes is modulated both during pregnancy and lactation to channel nutrients to the mammary epithelial cell. The fact that the changes occur in mammary adipocytes only when epithelial cells are present indicates that local as well as systemic factors are operating in these modulations

  13. Atrial natriuretic peptide regulates lipid mobilization and oxygen consumption in human adipocytes by activating AMPK

    International Nuclear Information System (INIS)

    Souza, Sandra C.; Chau, Mary D.L.; Yang, Qing; Gauthier, Marie-Soleil; Clairmont, Kevin B.; Wu, Zhidan; Gromada, Jesper; Dole, William P.

    2011-01-01

    Highlights: → Treatment of differentiated human adipocytes with atrial natriuretic peptide (ANP) increased lipolysis and oxygen consumption by activating AMP-activated protein kinase (AMPK). → ANP stimulated lipid mobilization by selective activation of the alpha2 subunit of AMPK and increased energy utilization through activation of both the alpha1 and alpha2 subunits of AMPK. → ANP enhanced adipocyte mitochondrial oxidative capacity as evidenced by induction of oxidative mitochondrial genes and increase in oxygen consumption. → Exposure of human adipocytes to fatty acids and (TNFα) induced insulin resistance and decreased expression of mitochondrial genes which was restored to normal by ANP. -- Abstract: Atrial natriuretic peptide (ANP) has been shown to regulate lipid and carbohydrate metabolism providing a possible link between cardiovascular function and metabolism by mediating the switch from carbohydrate to lipid mobilization and oxidation. ANP exerts a potent lipolytic effect via cGMP-dependent protein kinase (cGK)-I mediated-stimulation of AMP-activated protein kinase (AMPK). Activation of the ANP/cGK signaling cascade also promotes muscle mitochondrial biogenesis and fat oxidation. Here we demonstrate that ANP regulates lipid metabolism and oxygen utilization in differentiated human adipocytes by activating the alpha2 subunit of AMPK. ANP treatment increased lipolysis by seven fold and oxygen consumption by two fold, both of which were attenuated by inhibition of AMPK activity. ANP-induced lipolysis was shown to be mediated by the alpha2 subunit of AMPK as introduction of dominant-negative alpha2 subunit of AMPK attenuated ANP effects on lipolysis. ANP-induced activation of AMPK enhanced mitochondrial oxidative capacity as evidenced by a two fold increase in oxygen consumption and induction of mitochondrial genes, including carnitine palmitoyltransferase 1A (CPT1a) by 1.4-fold, cytochrome C (CytC) by 1.3-fold, and peroxisome proliferator

  14. Atrial natriuretic peptide regulates lipid mobilization and oxygen consumption in human adipocytes by activating AMPK

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Sandra C. [Translational Sciences - Translational Medicine, Novartis Institutes for Biomedical Research, Inc., 220 Massachusetts Avenue, Cambridge, MA 02139 (United States); Chau, Mary D.L.; Yang, Qing [Cardiovascular and Metabolism Disease Area, Novartis Institutes for Biomedical Research, Inc., 100 Technology Square, Cambridge, MA 02139 (United States); Gauthier, Marie-Soleil [Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA 02140 (United States); Clairmont, Kevin B.; Wu, Zhidan; Gromada, Jesper [Cardiovascular and Metabolism Disease Area, Novartis Institutes for Biomedical Research, Inc., 100 Technology Square, Cambridge, MA 02139 (United States); Dole, William P., E-mail: bill.dole@novartis.com [Translational Sciences - Translational Medicine, Novartis Institutes for Biomedical Research, Inc., 220 Massachusetts Avenue, Cambridge, MA 02139 (United States)

    2011-07-08

    Highlights: {yields} Treatment of differentiated human adipocytes with atrial natriuretic peptide (ANP) increased lipolysis and oxygen consumption by activating AMP-activated protein kinase (AMPK). {yields} ANP stimulated lipid mobilization by selective activation of the alpha2 subunit of AMPK and increased energy utilization through activation of both the alpha1 and alpha2 subunits of AMPK. {yields} ANP enhanced adipocyte mitochondrial oxidative capacity as evidenced by induction of oxidative mitochondrial genes and increase in oxygen consumption. {yields} Exposure of human adipocytes to fatty acids and (TNF{alpha}) induced insulin resistance and decreased expression of mitochondrial genes which was restored to normal by ANP. -- Abstract: Atrial natriuretic peptide (ANP) has been shown to regulate lipid and carbohydrate metabolism providing a possible link between cardiovascular function and metabolism by mediating the switch from carbohydrate to lipid mobilization and oxidation. ANP exerts a potent lipolytic effect via cGMP-dependent protein kinase (cGK)-I mediated-stimulation of AMP-activated protein kinase (AMPK). Activation of the ANP/cGK signaling cascade also promotes muscle mitochondrial biogenesis and fat oxidation. Here we demonstrate that ANP regulates lipid metabolism and oxygen utilization in differentiated human adipocytes by activating the alpha2 subunit of AMPK. ANP treatment increased lipolysis by seven fold and oxygen consumption by two fold, both of which were attenuated by inhibition of AMPK activity. ANP-induced lipolysis was shown to be mediated by the alpha2 subunit of AMPK as introduction of dominant-negative alpha2 subunit of AMPK attenuated ANP effects on lipolysis. ANP-induced activation of AMPK enhanced mitochondrial oxidative capacity as evidenced by a two fold increase in oxygen consumption and induction of mitochondrial genes, including carnitine palmitoyltransferase 1A (CPT1a) by 1.4-fold, cytochrome C (CytC) by 1.3-fold, and

  15. Ginkgolide C Suppresses Adipogenesis in 3T3-L1 Adipocytes via the AMPK Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Chian-Jiun Liou

    2015-01-01

    Full Text Available Ginkgolide C, isolated from Ginkgo biloba leaves, is a flavone reported to have multiple biological functions, from decreased platelet aggregation to ameliorating Alzheimer disease. The study aim was to evaluate the antiadipogenic effect of ginkgolide C in 3T3-L1 adipocytes. Ginkgolide C was used to treat differentiated 3T3-L1 cells. Cell supernatant was collected to assay glycerol release, and cells were lysed to measure protein and gene expression related to adipogenesis and lipolysis by western blot and real-time PCR, respectively. Ginkgolide C significantly suppressed lipid accumulation in differentiated adipocytes. It also decreased adipogenesis-related transcription factor expression, including peroxisome proliferator-activated receptor and CCAAT/enhancer-binding protein. Furthermore, ginkgolide C enhanced adipose triglyceride lipase and hormone-sensitive lipase production for lipolysis and increased phosphorylation of AMP-activated protein kinase (AMPK, resulting in decreased activity of acetyl-CoA carboxylase for fatty acid synthesis. In coculture with an AMPK inhibitor (compound C, ginkgolide C also improved activation of sirtuin 1 and phosphorylation of AMPK in differentiated 3T3-L1 cells. The results suggest that ginkgolide C is an effective flavone for increasing lipolysis and inhibiting adipogenesis in adipocytes through the activated AMPK pathway.

  16. Impaired response of mature adipocytes of diabetic mice to hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seok Jong, E-mail: seok-hong@northwestern.edu; Jin, Da P.; Buck, Donald W.; Galiano, Robert D.; Mustoe, Thomas A., E-mail: tmustoe@nmh.org

    2011-10-01

    Adipose tissue contains various cells such as infiltrated monocytes/macrophages, endothelial cells, preadipocytes, and adipocytes. Adipocytes have an endocrine function by secreting adipokines such as interleukin (IL)-6, tumor necrosis factor (TNF)-{alpha}, leptin, and adiponectin. Dysregulation of adipokines in adipose tissues leads to a chronic low-grade inflammation which could result in atherosclerosis, hypertension, and type 2 diabetes. A sustained inflammatory state, which is characterized by prolonged persistence of macrophages and neutrophils, is found in diabetic wounds. In addition, subcutaneous adipocytes are enormously increased in amount clinically in type 2 diabetes. However, the function of subcutaneous adipocytes, which play an important role in injured tissue subjected to hypoxia, has not been well characterized in vitro due to the difficulty of maintaining mature adipocytes in culture using conventional methods because of their buoyancy. In this study, we established a novel in vitro culture method of mature adipocytes by enclosing them in a hyaluronan (HA) based hydrogel to study their role in response to stress such as hypoxia. BrdU labeling and Ki67 immunostaining experiments showed that hydrogel enclosed mature adipocytes proliferate in vitro. Both mRNA and protein expression analyses for hypoxia regulated genes, such as vascular endothelial growth factor (VEGF) and heme oxygenase 1 (HO1), showed that mature adipocytes of wild type mice respond to hypoxia. In contrast, mature adipocytes of diabetic db/db and TallyHo mice did not efficiently respond to hypoxia. Our studies suggest that mature adipocytes are functionally active cells, and their abnormal function to hypoxia can be one of underlining mechanisms in type 2 diabetes.

  17. Adipocyte aminopeptidases in obesity and fasting.

    Science.gov (United States)

    Alponti, Rafaela Fadoni; Silveira, Paulo Flavio

    2015-11-05

    This study checked the existence of a diverse array of aminopeptidase (AP) enzymes in high (HDM) and low (LDM) density microsomal and plasma membrane (MF) fractions from adipocytes of control, monosodium glutamate obese and food deprived rats. Gene expression was detected for ArgAP, AspAP, MetAP, and two AlaAP (APM and PSA). APM and PSA had the highest catalytic efficiency, whereas AspAP the highest affinity. Subcellular distribution of AP activities depended on metabolic status. Comparing catalytic levels, AspAP in HDM, LDM and MF was absent in obese and control under food deprivation; PSA in LDM was 3.5-times higher in obese than in normally fed control and control and obese under food deprivation; MetAP in MF was 4.5-times higher in obese than in food deprived obese. Data show new AP enzymes genetically expressed in subcellular compartments of adipocytes, three of them with altered catalytic levels that respond to whole-body energetic demands. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. New metabolites of fenofibrate in Sprague–Dawley rats by UPLC-ESI-QTOF-MS-based metabolomics coupled with LC-MS/MS

    Science.gov (United States)

    Liu, A.; Chen, Y.; Yang, Z.; Feng, Y.; Rui, W.; Luo, W.; Liu, Y.; Gonzalez, F. J.; Dai, R.

    2009-01-01

    Fenofibrate has been widely used for the treatment of dyslipidaemia with a long history. Species differences of its metabolism were reported, but its metabolites in rodent have not been fully investigated.Urine and plasma samples were collected before and after oral dosages of fenofibrate in Sprague–Dawley rats. Urine samples were subjected to ultra-performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) analysis, and projection to latent structures discriminant analysis was used for the identification of metabolites.New metabolites in urine and plasma were also studied by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The metabolism pathway was studied in rat hepatocytes. Synthesized and purchased authentic compounds were used for metabolite identification by LC-MS/MS.Five ever-reported metabolites were identified and another four new ones were found. Among these new metabolites, fenofibric acid taurine and reduced fenofibric acid taurine indicate new phase II conjugation pathway of fenofibrate. PMID:19350456

  19. A New Approach to the RP-HPLC Method for Simultaneous Estimation of Atorvastatin Calcium and Fenofibrate in Pharmaceutical Dosage Forms

    Directory of Open Access Journals (Sweden)

    S. D. Bhinge

    2012-01-01

    Full Text Available The present manuscript describes the development and validation of an isocratic reverse phase high-performance liquid chromatographic (RP-HPLC method for the estimation of Atorvastatin calcium and Fenofibrate in raw material and tablet. Atorvastatin Calcium, Fenofibrate and Diclofenac (internal standard were well separated using a reversed phase column and mobile phase consisting of acetonitrile:KH2PO4 (50 mM (72:28 v/v (pH 4.1. The mobile phase was pumped at 1.0 mL/min flow rate and atorvastatin calcium and fenofibrate were detected by UV-Vis detection at 260 nm. The retention time for atorvastatin calcium, Internal Standard and fenofibrate were 4.34, 5.35 and 12.05 min, respectively. The LOD and LOQ was found to be 1.95 and 4.80 µg/mL for atorvastatin calcium whereas for fenofibrate it was found to be 1.73 and 3.98 µg/mL in mobile phase. The developed method was validated by applying parameters as precision, accuracy, selectivity, reproducibility and system suitability tests.

  20. Butyrate attenuates lipolysis in adipocytes co-cultured with macrophages through non-prostaglandin E2-mediated and prostaglandin E2-mediated pathways.

    Science.gov (United States)

    Ohira, Hideo; Tsutsui, Wao; Mamoto, Rie; Yamaguchi, Sayaka; Nishida, Masako; Ito, Miki; Fujioka, Yoshio

    2016-12-09

    Interactions between adipocytes and macrophages are associated with metabolic disorders. Production of pro-inflammatory mediators and the release of free fatty acids (FFAs) increase when these cells are co-cultured; butyrate significantly diminishes these effects by suppressing both the macrophage inflammatory and adipocyte lipolysis pathways. Butyrate is known to up-regulate the expression of prostaglandin E2 (PGE2). Therefore, we hypothesized that PGE2 is associated with the suppression of lipolysis by butyrate in co-culture. Using contact or transwell co-culture methods with differentiated 3T3-L1 adipocytes and RAW264.7 macrophages, we investigated the effects of butyrate on the release of PGE2 into the medium and on lipolysis in adipocytes. To elucidate the underlying mechanism, we examined the effects of butyrate on cyclooxygenase-2 (COX2) and phospholipase A2 (PLA2) in co-cultured cells, and cyclic adenine monophosphate (cAMP) and protein kinase A type 1-α regulatory subunit (PRKAR1A) in co-cultured adipocytes. Silent interfering (si)RNA targeting of G-protein-coupled receptor (GPR)41 and 109A was employed to examine the effect on lipolysis in TNF-α-stimulated adipocytes. Co-culture increased PGE2 release into the medium, compared with cells cultured separately. Butyrate significantly increased PGE2 production. Co-culture elevated COX2 expression in macrophages and adipocytes, and butyrate further enhanced this effect. Co-culture enhanced cytosolic PLA2 activity in macrophages, which was further enhanced by butyrate. As for lipolysis, co-culture increased the release of FFAs and free glycerol into the medium, whereas butyrate (and to a lesser extent, PGE2) suppressed FFAs and free glycerol release. An inhibition study using a prostaglandin E receptor 3-selective antagonist suggested that approximately 40% of the suppressive effect of butyrate depends on the PGE2-mediated pathway, whereas 60% depends on a non-PGE2-mediated pathway. Co-culture increased c

  1. Hypochlorous acid via peroxynitrite activates protein kinase Cθ and insulin resistance in adipocytes.

    Science.gov (United States)

    Zhou, Jun; Wang, Qilong; Ding, Ye; Zou, Ming-Hui

    2015-02-01

    We recently reported that genetic deletion of myeloperoxidase (MPO) alleviates obesity-related insulin resistance in mice in vivo. How MPO impairs insulin sensitivity in adipocytes is poorly characterized. As hypochlorous acid (HOCl) is a principal oxidant product generated by MPO, we evaluated the effects of HOCl on insulin signaling in adipocytes differentiated from 3T3-L1 cells. Exposure of 3T3-L1 adipocytes to exogenous HOCl (200 μmol/l) attenuated insulin-stimulated 2-deoxyglucose uptake, GLUT4 translocation, and insulin signals, including tyrosine phosphorylation of insulin receptor substrate 1 (IRS1) and phosphorylation of Akt. Furthermore, treatment with HOCl induced phosphorylation of IRS1 at serine 307, inhibitor κB kinase (IKK), c-Jun NH2-terminal kinase (JNK), and phosphorylation of PKCθ (PKCθ). In addition, genetic and pharmacological inhibition of IKK and JNK abolished serine phosphorylation of IRS1 and impairment of insulin signaling by HOCl. Furthermore, knockdown of PKCθ using siRNA transfection suppressed phosphorylation of IKK and JNK and consequently attenuated the HOCl-impaired insulin signaling pathway. Moreover, activation of PKCθ by peroxynitrite was accompanied by increased phosphorylation of IKK, JNK, and IRS1-serine 307. In contrast, ONOO(-) inhibitors abolished HOCl-induced phosphorylation of PKCθ, IKK, JNK, and IRS1-serine 307, as well as insulin resistance. Finally, high-fat diet (HFD)-induced insulin resistance was associated with enhanced phosphorylation of PKCθ, IKK, JNK, and IRS1 at serine 307 in white adipose tissues from WT mice, all of which were not found in Mpo knockout mice fed HFDs. We conclude that HOCl impairs insulin signaling pathway by increasing ONOO(-) mediated phosphorylation of PKCθ, resulting in phosphorylation of IKK/JNK and consequent serine phosphorylation of IRS1 in adipocytes. © 2015 The authors.

  2. Molecular Mechanisms of Fenofibrate-Induced Metabolic Catastrophe and Glioblastoma Cell Death

    Science.gov (United States)

    Wilk, Anna; Wyczechowska, Dorota; Zapata, Adriana; Dean, Matthew; Mullinax, Jennifer; Marrero, Luis; Parsons, Christopher; Peruzzi, Francesca; Culicchia, Frank; Ochoa, Augusto; Grabacka, Maja

    2014-01-01

    Fenofibrate (FF) is a common lipid-lowering drug and a potent agonist of the peroxisome proliferator-activated receptor alpha (PPARα). FF and several other agonists of PPARα have interesting anticancer properties, and our recent studies demonstrate that FF is very effective against tumor cells of neuroectodermal origin. In spite of these promising anticancer effects, the molecular mechanism(s) of FF-induced tumor cell toxicity remains to be elucidated. Here we report a novel PPARα-independent mechanism explaining FF's cytotoxicity in vitro and in an intracranial mouse model of glioblastoma. The mechanism involves accumulation of FF in the mitochondrial fraction, followed by immediate impairment of mitochondrial respiration at the level of complex I of the electron transport chain. This mitochondrial action sensitizes tested glioblastoma cells to the PPARα-dependent metabolic switch from glycolysis to fatty acid β-oxidation. As a consequence, prolonged exposure to FF depletes intracellular ATP, activates the AMP-activated protein kinase–mammalian target of rapamycin–autophagy pathway, and results in extensive tumor cell death. Interestingly, autophagy activators attenuate and autophagy inhibitors enhance FF-induced glioblastoma cytotoxicity. Our results explain the molecular basis of FF-induced glioblastoma cytotoxicity and reveal a new supplemental therapeutic approach in which intracranial infusion of FF could selectively trigger metabolic catastrophe in glioblastoma cells. PMID:25332241

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  11. File list: NoD.Adp.20.AllAg.White_adipocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Adp.20.AllAg.White_adipocytes mm9 No description Adipocyte White adipocytes htt...p://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Adp.20.AllAg.White_adipocytes.bed ...

  12. File list: ALL.Adp.50.AllAg.Brown_adipocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Adp.50.AllAg.Brown_adipocytes mm9 All antigens Adipocyte Brown adipocytes SRX80...X800019,SRX185797,SRX478163,SRX478162 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Adp.50.AllAg.Brown_adipocytes.bed ...

  13. Sulforaphane induces adipocyte browning and promotes glucose and lipid utilization.

    Science.gov (United States)

    Zhang, Hui Q; Chen, Shi Y; Wang, An S; Yao, An J; Fu, Jian F; Zhao, Jin S; Chen, Fen; Zou, Zu Q; Zhang, Xiao H; Shan, Yu J; Bao, Yong P

    2016-10-01

    Obesity is closely related to the imbalance of white adipose tissue storing excess calories, and brown adipose tissue dissipating energy to produce heat in mammals. Recent studies revealed that acquisition of brown characteristics by white adipocytes, termed "browning," may positively contribute to cellular bioenergetics and metabolism homeostasis. The goal was to investigate the putative effects of natural antioxidant sulforaphane (1-isothiocyanate-4-methyl-sulfonyl butane; SFN) on browning of white adipocytes. 3T3-L1 mature white adipocytes were treated with SFN for 48 h, and then the mitochondrial content, function, and energy utilization were assessed. SFN was found to induce 3T3-L1 adipocytes browning based on the increased mitochondrial content and activity of respiratory chain enzymes, whereas the mechanism involved the upregulation of nuclear factor E2-related factor 2/sirtuin1/peroxisome proliferator activated receptor gamma coactivator 1 alpha signaling. SFN enhanced uncoupling protein 1 expression, a marker for brown adipocyte, leading to the decrease in cellular ATP. SFN also enhanced glucose uptake and oxidative utilization, lipolysis, and fatty acid oxidation in 3T3-L1 adipocytes. SFN-induced browning of white adipocytes enhanced the utilization of cellular fuel, and application of SFN is a promising strategy to combat obesity and obesity-related metabolic disorder. © 2016 The Authors. Molecular Nutrition & Food Research Published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Perilipin 3 Deficiency Stimulates Thermogenic Beige Adipocytes Through PPARα Activation.

    Science.gov (United States)

    Lee, Yun Kyung; Sohn, Jee Hyung; Han, Ji Seul; Park, Yoon Jeong; Jeon, Yong Geun; Ji, Yul; Dalen, Knut Tomas; Sztalryd, Carole; Kimmel, Alan R; Kim, Jae Bum

    2018-02-13

    Beige adipocytes can dissipate energy as heat. Elaborate communication between metabolism and gene expression is important in the regulation of beige adipocytes. While lipid droplet (LD)-binding proteins play important roles in adipose tissue biology, it remains unknown whether perilipin 3 ( Plin3 ) is involved in the regulation of beige adipocyte formation and thermogenic activities. Here, we demonstrate that Plin3 ablation stimulates beige adipocytes and thermogenic gene expression in inguinal white adipose tissue (iWAT). Compared to wild-type mice, Plin3 knockout mice were cold-tolerant and displayed enhanced basal and stimulated lipolysis in iWAT, inducing PPARα activation. In adipocytes, Plin3 deficiency promoted PPARα target gene and UCP1 expression and multilocular LD formation upon cold stimulus. Moreover, FGF21 expression and secretion were upregulated, which was attributable to activated PPARα in Plin3 -deficient adipocytes. These data suggest that Plin3 acts as an intrinsic protective factor preventing futile beige adipocyte formation by limiting lipid metabolism and thermogenic gene expression. © 2018 by the American Diabetes Association.

  15. Thermogenic adipocytes: from cells to physiology and medicine.

    Science.gov (United States)

    Diaz, Mauricio Berriel; Herzig, Stephan; Vegiopoulos, Alexandros

    2014-10-01

    The identification of active brown fat in humans has evoked widespread interest in the biology of non-shivering thermogenesis among basic and clinical researchers. As a consequence we have experienced a plethora of contributions related to cellular and molecular processes in thermogenic adipocytes as well as their function in the organismal context and their relevance to human physiology. In this review we focus on the cellular basis of non-shivering thermogenesis, particularly in relation to human health and metabolic disease. We provide an overview of the cellular function and distribution of thermogenic adipocytes in mouse and humans, and how this can be affected by environmental factors, such as prolonged cold exposure. We elaborate on recent evidence and open questions on the distinction of classical brown versus beige/brite adipocytes. Further, the origin of thermogenic adipocytes as well as current models for the recruitment of beige/brite adipocytes is discussed with an emphasis on the role of progenitor cells. Focusing on humans, we describe the expanding evidence for the activity, function and physiological relevance of thermogenic adipocytes. Finally, as the potential of thermogenic adipocyte activation as a therapeutic approach for the treatment of obesity and associated metabolic diseases becomes evident, we highlight goals and challenges for current research on the road to clinical translation. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Effects of Epigallocatechin-3-Gallate on Autophagic Lipolysis in Adipocytes

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    Sang-Nam Kim

    2017-06-01

    Full Text Available Previous studies demonstrated effects of green tea on weight loss; however, green tea-induced modulation of adipocyte function is not fully understood. Here, we investigated effects of the major green tea phytochemical, epigallocatechin-3-gallate (EGCG on triglyceride contents, lipolysis, mitochondrial function, and autophagy, in adipocytes differentiated from C3H10T1/2 cells and immortalized pre-adipocytes in vitro. EGCG reduced the triglycerol content significantly in adipocytes by 25%, comparable to the nutrient starvation state. EGCG did not affect protein kinase A signaling or brown adipocyte marker expression in adipocytes; however, EGCG increased autophagy, as measured by autophagy flux analysis and immunoblot analysis of LC3B, ATG7, and Beclin1. EGCG treatment reduced mitochondrial membrane potential by 56.8% and intracellular ATP levels by 49.1% compared to controls. Although mammalian target of rapamycin signaling was not upregulated by EGCG treatment, EGCG treatment induced AMP-activated protein kinase phosphorylation, indicating an energy-depleted state. In addition, EGCG increased the association between RAB7 and lipid droplets, suggesting that lipophagy was activated. Finally, knockdown of Rab7 attenuated the EGCG-dependent reduction in lipid contents. Collectively, these results indicated that EGCG upregulated autophagic lipolysis in adipocytes, supporting the therapeutic potential of EGCG as a caloric restriction mimetic to prevent obesity and obesity-related metabolic diseases.

  17. Female adipocyte androgen synthesis and the effects of insulin

    Directory of Open Access Journals (Sweden)

    David Cadagan

    2014-01-01

    Full Text Available The metabolic syndrome is a cluster of metabolic disorders characterized by insulin resistance and hyperinsulinaemia, and its presence can increase the risk of cardiovascular disease significantly. The metabolic syndrome is associated with increased circulating androgen levels in women, which may originate from the ovaries and adrenal glands. Adipocytes are also able to synthesise steroid hormones, and this output has been hypothesised to increase with elevated insulin plasma concentrations. However, the contribution of the adipocytes to the circulating androgen levels in women with metabolic syndrome is limited and the effects of insulin are not fully understood. The aim of this study was to investigate the presence of steroid precursors and synthetic enzymes in human adipocyte biopsies as markers of possible adipocyte androgen synthesis. We examined pre and mature adipocytes taken from tissue biopsies of abdominal subcutaneous adipose tissue of participating women from the Department of Obstetrics and Gynaecology, of the Royal Derby Hospital. The results showed the potential for localised adipocyte androgen synthesis through the presence of the androgen precursor progesterone, as well as the steroid-converting enzyme 17α-hydroxylase. Furthermore, we found the controlled secretion of androstenedione in vitro and that insulin treatment caused levels to increase. Continued examination of a localised source of androgen production is therefore of clinical relevance due to its influence on adipocyte metabolism, its negative impact on female steroidogenic homeostasis, and the possible aggravation this may have when associated to obesity and obesity related metabolic abnormalities such as hyperinsulinaemia.

  18. Lipolytic efficacy of alginate double-layer nanoemulsion containing oleoresin capsicum in differentiated 3T3-L1 adipocytes.

    Science.gov (United States)

    Lee, Mak-Soon; Jung, Sunyoon; Shin, Yoonjin; Lee, Seohyun; Kim, Chong-Tai; Kim, In-Hwan; Kim, Yangha

    2017-01-01

    Background : Oleoresin capsicum (OC) is an organic extract from fruits of the genus Capsicum , and has been reported to have an anti-obesity effect. Objective : This study comparatively investigated lipolytic effects of single-layer nanoemulsion (SN) and alginate double-layer nanoemulsion (AN) containing OC in 3T3-L1 adipocytes. Methods : SN and AN were compared by analyzing the intracellular lipid accumulation, triglyceride (TG) content, release of free fatty acids (FFAs) and glycerol, and mRNA expression of genes related to adipogenesis and lipolysis were analyzed in fully differentiated 3T3-L1 adipocytes. Results : Compared with SN, AN exhibited higher efficiency in inhibiting the intracellular lipid accumulation and TG content, and enhanced the release of FFAs and glycerol into the medium. In AN-treated cells, mRNA levels of peroxisome proliferator-activated receptor-γ and the fatty acid-binding protein adipocyte protein-2, which are involved in adipogenesis, were down-regulated, whereas those of genes related to lipolysis, including hormone-sensitive lipase and carnitine palmitoyl transferase-1α, were up-regulated compared with SN-treated cells. Conclusion : The lipolytic effect of AN was greater than that of SN; this was partly associated with the increased TG hydrolysis via induction of lipolytic gene expression and suppression of adipogenic gene expression in 3T3-L1 adipocytes.​​​​.

  19. Regulation of Autophagy-Related Protein and Cell Differentiation by High Mobility Group Box 1 Protein in Adipocytes

    Directory of Open Access Journals (Sweden)

    Huanhuan Feng

    2016-01-01

    Full Text Available High mobility group box 1 protein (HMGB1 is a molecule related to the development of inflammation. Autophagy is vital to maintain cellular homeostasis and protect against inflammation of adipocyte injury. Our recent work focused on the relationship of HMGB1 and autophagy in 3T3-L1 cells. In vivo experimental results showed that, compared with the normal-diet group, the high-fat diet mice displayed an increase in adipocyte size in the epididymal adipose tissues. The expression levels of HMGB1 and LC3II also increased in epididymal adipose tissues in high-fat diet group compared to the normal-diet mice. The in vitro results indicated that HMGB1 protein treatment increased LC3II formation in 3T3-L1 preadipocytes in contrast to that in the control group. Furthermore, LC3II formation was inhibited through HMGB1 knockdown by siRNA. Treatment with the HMGB1 protein enhanced LC3II expression after 2 and 4 days but decreased the expression after 8 and 10 days among various differentiation stages of adipocytes. By contrast, FABP4 expression decreased on the fourth day and increased on the eighth day. Hence, the HMGB1 protein modulated autophagy-related proteins and lipid-metabolism-related genes in adipocytes and could be a new target for treatment of obesity and related metabolic diseases.

  20. The Gustatory Signaling Pathway and Bitter Taste Receptors Affect the Development of Obesity and Adipocyte Metabolism in Mice.

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    Bert Avau

    Full Text Available Intestinal chemosensory signaling pathways involving the gustatory G-protein, gustducin, and bitter taste receptors (TAS2R have been implicated in gut hormone release. Alterations in gut hormone profiles may contribute to the success of bariatric surgery. This study investigated the involvement of the gustatory signaling pathway in the development of diet-induced obesity and the therapeutic potential of targeting TAS2Rs to induce body weight loss. α-gustducin-deficient (α-gust-/- mice became less obese than wild type (WT mice when fed a high-fat diet (HFD. White adipose tissue (WAT mass was lower in α-gust-/- mice due to increased heat production as a result of increases in brown adipose tissue (BAT thermogenic activity, involving increased protein expression of uncoupling protein 1. Intra-gastric treatment of obese WT and α-gust-/- mice with the bitter agonists denatonium benzoate (DB or quinine (Q during 4 weeks resulted in an α-gustducin-dependent decrease in body weight gain associated with a decrease in food intake (DB, but not involving major changes in gut peptide release. Both WAT and 3T3-F442A pre-adipocytes express TAS2Rs. Treatment of pre-adipocytes with DB or Q decreased differentiation into mature adipocytes. In conclusion, interfering with the gustatory signaling pathway protects against the development of HFD-induced obesity presumably through promoting BAT activity. Intra-gastric bitter treatment inhibits weight gain, possibly by directly affecting adipocyte metabolism.

  1. The thermogenic actions of natriuretic peptide in brown adipocytes: The direct measurement of the intracellular temperature using a fluorescent thermoprobe.

    Science.gov (United States)

    Kimura, Haruka; Nagoshi, Tomohisa; Yoshii, Akira; Kashiwagi, Yusuke; Tanaka, Yoshiro; Ito, Keiichi; Yoshino, Takuya; Tanaka, Toshikazu D; Yoshimura, Michihiro

    2017-10-11

    In addition to the various effects of natriuretic peptides (NPs) on cardiovascular systems, increasing attention is being paid to the possibility that NPs induce adipose tissue browning and activate thermogenic program. We herein established a direct intracellular temperature measurement system using a fluorescent thermoprobe and investigated the thermogenic effects of A-type NP (ANP) on brown adipocytes. The thermoprobe was successfully introduced into rat brown adipocytes, and the temperature dependent change in fluorescence intensity ratio was measured using a fluorescence microscope. After one-hour incubation with ANP, the degree of the change in fluorescence intensity ratio was significantly higher in ANP-treated (P thermogenic actions of ANP were more prominent when brown adipocytes were incubated at 35 °C than at 37 °C. Moreover, the increase in the intracellular temperature and the expression of UCP1 induced by ANP were cancelled by p38MAPK inhibition. Taken together, this study directly demonstrated the thermogenic actions of ANP in brown adipocytes through the use of a novel method of intracellular temperature measurement.

  2. Obestatin as a regulator of adipocyte metabolism and adipogenesis

    Science.gov (United States)

    Gurriarán-Rodríguez, Uxía; Al-Massadi, Omar; Roca-Rivada, Arturo; Crujeiras, Ana Belén; Gallego, Rosalía; Pardo, Maria; Seoane, Luisa Maria; Pazos, Yolanda; Casanueva, Felipe F; Camiña, Jesús P

    2011-01-01

    Abstract The role of obestatin, a 23-amino-acid peptide encoded by the ghrelin gene, on the control of the metabolism of pre-adipocyte and adipocytes as well as on adipogenesis was determined. For in vitro assays, pre-adipocyte and adipocyte 3T3-L1 cells were used to assess the obestatin effect on cell metabolism and adipogenesis based on the regulation of the key enzymatic nodes, Akt and AMPK and their downstream targets. For in vivo assays, white adipose tissue (WAT) was obtained from male rats under continuous subcutaneous infusion of obestatin. Obestatin activated Akt and its downstream targets, GSK3α/β, mTOR and S6K1, in 3T3-L1 adipocyte cells. Simultaneously, obestatin inactivated AMPK in this cell model. In keeping with this, ACC phosphorylation was also decreased. This fact was confirmed in vivo in white adipose tissue (omental, subcutaneous and gonadal) obtained from male rats under continuous sc infusion of obestatin (24 and 72 hrs). The relevance of obestatin as regulator of adipocyte metabolism was supported by AS160 phosphorylation, GLUT4 translocation and augment of glucose uptake in 3T3-L1 adipocyte cells. In contrast, obestatin failed to modify translocation of fatty acid transporters, FATP1, FATP4 and FAT/CD36, to plasma membrane. Obestatin treatment in combination with IBMX and DEX showed to regulate the expression of C/EBPα, C/EBPβ, C/EBPδ and PPARγ promoting adipogenesis. Remarkable, preproghrelin expression, and thus obestatin expression, increased during adipogenesis being sustained throughout terminal differentiation. Neutralization of endogenous obestatin secreted by 3T3-L1 cells by anti-obestatin antibody decreased adipocyte differentiation. Furthermore, knockdown experiments by preproghrelin siRNA supported that obestatin contributes to adipogenesis. In summary, obestatin promotes adipogenesis in an autocrine/paracrine manner, being a regulator of adipocyte metabolism. These data point to a putative role in the pathogenesis of

  3. Euglena extract suppresses adipocyte-differentiation in human adipose-derived stem cells.

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    Ryota Sugimoto

    Full Text Available Euglena gracilis Z (Euglena is a unicellular, photosynthesizing, microscopic green alga. It contains several nutrients such as vitamins, minerals, and unsaturated fatty acids. In this study, to verify the potential role of Euglena consumption on human health and obesity, we evaluated the effect of Euglena on human adipose-derived stem cells. We prepared a Euglena extract and evaluated its effect on cell growth and lipid accumulation, and found that cell growth was promoted by the addition of the Euglena extract. Interestingly, intracellular lipid accumulation was inhibited in a concentration-dependent manner. Quantitative real-time PCR analysis and western blotting analysis indicated that the Euglena extract suppressed adipocyte differentiation by inhibiting the gene expression of the master regulators peroxisome proliferator-activated receptor-γ (PPARγ and one of three CCAAT-enhancer-binding proteins (C/EBPα. Further Oil Red O staining experiments indicated that the Euglena extract inhibited the early stage of adipocyte-differentiation. Consistent with these results, we observed that down-regulation of gene expression was involved in the early stage of adipogenesis represented by the sterol regulatory element binding protein 1 c (SREBP1c, two of three CCAAT-enhancer-binding proteins (C/EBPβ, C/EBPδ, and the cAMP regulatory element-binding protein (CREB. Taken together, these data suggest that Euglena extract is a promising candidate for the development of a new therapeutic treatment for obesity.

  4. Euglena extract suppresses adipocyte-differentiation in human adipose-derived stem cells.

    Science.gov (United States)

    Sugimoto, Ryota; Ishibashi-Ohgo, Naoko; Atsuji, Kohei; Miwa, Yuko; Iwata, Osamu; Nakashima, Ayaka; Suzuki, Kengo

    2018-01-01

    Euglena gracilis Z (Euglena) is a unicellular, photosynthesizing, microscopic green alga. It contains several nutrients such as vitamins, minerals, and unsaturated fatty acids. In this study, to verify the potential role of Euglena consumption on human health and obesity, we evaluated the effect of Euglena on human adipose-derived stem cells. We prepared a Euglena extract and evaluated its effect on cell growth and lipid accumulation, and found that cell growth was promoted by the addition of the Euglena extract. Interestingly, intracellular lipid accumulation was inhibited in a concentration-dependent manner. Quantitative real-time PCR analysis and western blotting analysis indicated that the Euglena extract suppressed adipocyte differentiation by inhibiting the gene expression of the master regulators peroxisome proliferator-activated receptor-γ (PPARγ) and one of three CCAAT-enhancer-binding proteins (C/EBPα). Further Oil Red O staining experiments indicated that the Euglena extract inhibited the early stage of adipocyte-differentiation. Consistent with these results, we observed that down-regulation of gene expression was involved in the early stage of adipogenesis represented by the sterol regulatory element binding protein 1 c (SREBP1c), two of three CCAAT-enhancer-binding proteins (C/EBPβ, C/EBPδ), and the cAMP regulatory element-binding protein (CREB). Taken together, these data suggest that Euglena extract is a promising candidate for the development of a new therapeutic treatment for obesity.

  5. Bisindoylmaleimide I suppresses adipocyte differentiation through stabilization of intracellular β-catenin protein

    International Nuclear Information System (INIS)

    Cho, Munju; Park, Seoyoung; Gwak, Jungsug; Kim, Dong-Eun; Yea, Sung Su; Shin, Jae-Gook; Oh, Sangtaek

    2008-01-01

    The Wnt/β-catenin signaling pathway plays important roles in cell differentiation. Activation of this pathway, likely by Wnt-10b, has been shown to inhibit adipogenesis in cultured 3T3-L1 preadipocytes and mice. Here we revealed that bisindoylmaleimide I (BIM), which is widely used as a specific inhibitor of protein kinase C (PKC), inhibits adipocyte differentiation through activation of the Wnt/β-catenin signaling pathway. BIM increased β-catenin responsive transcription (CRT) and up-regulated intracellular β-catenin levels in HEK293 cells and 3T3-L1 preadipocytes. BIM significantly decreased intracellular lipid accumulation and reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated receptor γ (PPARγ) and CAATT enhancer-binding protein α (C/EBPα) in 3T3-L1 preadipocytes. Taken together, our findings indicate that BIM inhibits adipogenesis by increasing the stability of β-catenin protein in 3T3-L1 preadipocyte cells

  6. Development of self-nanoemulsifying drug delivery systems for the enhancement of solubility and oral bioavailability of fenofibrate, a poorly water-soluble drug.

    Science.gov (United States)

    Mohsin, Kazi; Alamri, Rayan; Ahmad, Ajaz; Raish, Mohammad; Alanazi, Fars K; Hussain, Muhammad Delwar

    2016-01-01

    Self-nanoemulsifying drug delivery systems (SNEDDS) have become a popular formulation option as nanocarriers for poorly water-soluble drugs. The objective of this study was to investigate the factor that can influence the design of successful lipid formulation classification system (LFCS) Type III SNEDDS formulation and improve the oral bioavailability (BA) of fenofibrate. LFCS Type III SNEDDS were designed using various oils, water-soluble surfactants, and/or cosolvents (in considering the polarity of the lipids) for the model anticholesterol drug, fenofibrate. The developed SNEDDS were assessed visually and by measurement of the droplet size. Equilibrium solubility of fenofibrate in the SNEDDS was conducted to find out the maximum drug loading. Dynamic dispersion studies were carried out (1/100 dilution) in water to investigate how much drug stays in solution after aqueous dispersion of the formulation. The BA of SNEDDS formulation was evaluated in the rat. The results from the characterization and solubility studies showed that formulations containing mixed glycerides were highly efficient SNEDDS as they had higher solubility of the drug and produced nanosized droplets. The dispersion studies confirmed that SNEDDS (containing polar mixed glycerides) can retain >98% drug in solution for >24 hours in aqueous media. The in vivo pharmacokinetics parameters of SNEDDS formulation in comparison with pure drug showed significant increase in C max and AUC0- t , ~78% and 67%, respectively. The oral BA of fenofibrate from SNEDDS in rats was ~1.7-fold enhanced as compared with the BA from pure drug. Fenofibrate-loaded LFCS Type III SNEDDS formulations could be a potential oral pharmaceutical product for administering the poorly water-soluble drug, fenofibrate, with an enhanced oral BA.

  7. The Dietary Isoflavone Daidzein Reduces Expression of Pro-Inflammatory Genes through PPARα/γ and JNK Pathways in Adipocyte and Macrophage Co-Cultures.

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    Yuri Sakamoto

    Full Text Available Obesity-induced inflammation caused by adipocyte-macrophage interactions plays a critical role in developing insulin resistance, and peroxisome proliferator-activated receptors (PPARs regulate inflammatory gene expression in these cells. Recently, the soy isoflavone daidzein was reported to act as a PPAR activator. We examined whether daidzein affected adipocyte-macrophage crosstalk via the regulation of PPARs. Co-cultures of 3T3-L1 adipocytes and RAW264 macrophages, or palmitate-stimulated RAW264 macrophages were treated with daidzein in the presence or absence of specific inhibitors for PPARs: GW6471 (a PPARα antagonist, and GW9662 (a PPARγ antagonist. Inflammatory gene expression was then determined. Daidzein significantly decreased chemokine (C-C motif ligand 2 (Ccl2, known in humans as monocyte chemo-attractant protein 1 (MCP1 and interleukin 6 (Il6 mRNA levels induced by co-culture. In 3T3-L1 adipocytes, daidzein inversed the attenuation of adiponectin gene expression by co-culture, and these effects were inhibited by the PPAR-γ specific inhibitor. Daidzein also decreased Ccl2 and Il6 mRNA levels in RAW264 macrophages stimulated with palmitate or conditioned medium (CM from hypertrophied 3T3-L1 adipocytes. This inhibitory effect on Il6 expression was abrogated by a PPAR-α inhibitor. Additionally, we examined the activation of nuclear factor-kappa B (NF-κB and c-Jun N-terminal kinase (JNK pathways and found that daidzein significantly inhibited palmitate-induced phosphorylation of JNK. Our data suggest that daidzein regulates pro-inflammatory gene expression by activating PPAR-α and -γ and inhibiting the JNK pathway in adipocyte and macrophage co-cultures. These effects might be favorable in improving adipose inflammation, thus, treatment of daidzein may be a therapeutic strategy for chronic inflammation in obese adipose tissue.

  8. Thermogenic ability of uncoupling protein 1 in beige adipocytes in mice.

    Science.gov (United States)

    Okamatsu-Ogura, Yuko; Fukano, Keigo; Tsubota, Ayumi; Uozumi, Akihiro; Terao, Akira; Kimura, Kazuhiro; Saito, Masayuki

    2013-01-01

    Chronic adrenergic activation leads to the emergence of beige adipocytes in some depots of white adipose tissue in mice. Despite their morphological similarities to brown adipocytes and their expression of uncoupling protein 1 (UCP1), a thermogenic protein exclusively expressed in brown adipocytes, the beige adipocytes have a gene expression pattern distinct from that of brown adipocytes. However, it is unclear whether the thermogenic function of beige adipocytes is different from that of classical brown adipocytes existing in brown adipose tissue. To examine the thermogenic ability of UCP1 expressed in beige and brown adipocytes, the adipocytes were isolated from the fat depots of C57BL/6J mice housed at 24°C (control group) or 10°C (cold-acclimated group) for 3 weeks. Morphological and gene expression analyses revealed that the adipocytes isolated from brown adipose tissue of both the control and cold-acclimated groups consisted mainly of brown adipocytes. These brown adipocytes contained large amounts of UCP1 and increased their oxygen consumption when stimulated with norepinephirine. Adipocytes isolated from the perigonadal white adipose tissues of both groups and the inguinal white adipose tissue of the control group were white adipocytes that showed no increase in oxygen consumption after norepinephrine stimulation. Adipocytes isolated from the inguinal white adipose tissue of the cold-acclimated group were a mixture of white and beige adipocytes, which expressed UCP1 and increased their oxygen consumption in response to norepinephrine. The UCP1 content and thermogenic ability of beige adipocytes estimated on the basis of their abundance in the cell mixture were similar to those of brown adipocytes. These results revealed that the inducible beige adipocytes have potent thermogenic ability comparable to classical brown adipocytes.

  9. Dodecylamine Template-Based Hexagonal Mesoporous Silica (HMS) as a Carrier for Improved Oral Delivery of Fenofibrate.

    Science.gov (United States)

    Jadhav, Nitin V; Vavia, Pradeep R

    2017-10-01

    The aim of present investigation was the preparation of dodecylamine template-based hexagonal mesoporous silica (HMS) as a carrier for poorly water-soluble drug (fenofibrate). HMS material has distinctive characteristics such as easy synthesis, high surface area and wormhole pores. These characteristics are highly admirable to make use of it as a carrier in drug delivery system. HMS was prepared by pH and temperature-independent process. Fenofibrate was loaded into the HMS by solvent immersion method using organic solvent. The BET surface area of HMS was evaluated by nitrogen adsorption/desorption analysis. HMS and drug-loaded HMS were characterized by differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and contact angle study. The HMS-based system was also evaluated for in vitro and in vivo study as compared to plain drug. The BET surface area of HMS was found 974 m 2 /g with a narrow pore size average of 2.6 nm. The DSC and XRD study confirmed the amorphization of drug within the HMS. SEM and TEM study showed morphological features of HMS as well as revealed the wormhole porous structure. Contact angle study showed improvement in aqueous wetting property of drug within the HMS (contact angle 46°). The In vitro drug release study showed a remarkable dissolution enhancement in HMS-based system as compared to plain drug. In vivo pharmacodynamic study (hyperlipidaemia model) exhibited HMS-based formulation was significantly improved the bioavailability of fenofibrate. Thus, HMS has admirable properties; makes it a potential carrier for delivery system of poorly water-soluble drugs.

  10. Adipocyte differentiation of 3T3-L1 preadipocytes is dependent on lipoxygenase activity during the initial stages of the differentiation process

    DEFF Research Database (Denmark)

    Madsen, Lise; Petersen, Rasmus K; Sørensen, Morten B

    2003-01-01

    (nordihydroguaiaretic acid) and the 12/15-LOX selective inhibitor baicalein. Baicalein-mediated inhibition of adipocyte differentiation was rescued by administration of rosiglitazone. Treatment with baicalein during the first 4 days of the differentiation process prevented adipocyte differentiation; supplementation...... with rosiglitazone during the same period was sufficient to rescue adipogenesis. Accordingly, we demonstrate that adipogenic conversion of 3T3-L1 cells requires PPARgamma ligands only during the first 4 days of the differentiation process. We show that the baicalein-sensitive synthesis of endogenous PPARgamma ligand...

  11. Arachidonic acid has a dominant effect to regulate lipogenic genes in 3T3-L1 adipocytes compared to omega-3 fatty acids

    Directory of Open Access Journals (Sweden)

    Hitesh Vaidya

    2015-03-01

    Full Text Available Background: The effects of long-chain n-3 and n-6 polyunsaturated fatty acids (PUFA on the regulation of adipocytes metabolism are well known. These fatty acids are generally consumed together in our diets; however, the metabolic regulation of adipocytes in the presence of these fatty acids when given together is not known. Objective: To investigate the effects of n-3 PUFA and arachidonic acid (AA, an n-6 PUFA, on the regulation of adipogenic and lipogenic genes in mature 3T3-L1 adipocytes. Methods: 3T3-L1 adipocytes were incubated in the presence or absence of 100 µM of eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA; docosapentaenoic acid, DPA and AA, either alone or AA+n-3 PUFA; control cells received bovine serum albumin alone. The mRNA expression of adipogenic and lipogenic genes was measured. The fatty acid composition of adipocytes was analyzed using gas chromatography. Results: Individual n-3 PUFA or AA had no effect on the mRNA expression of peroxisome-proliferator-activated receptor-γ; however, AA+EPA and AA+DPA significantly increased (P<0.05 the expression compared to control cells (38 and 42%, respectively. AA and AA+EPA increased the mRNA expression of acetyl-CoA carboxylase 1 (P<0.05. AA treatment decreased the mRNA expression of stearoyl-CoA desaturase (SCD1 (P<0.01, while n-3 PUFA, except EPA, had no effect compared to control cells. AA+DHA and AA+DPA inhibited SCD1 gene expression (P<0.05 suggesting a dominant effect of AA. Fatty acids analysis of adipocytes revealed a higher accretion of AA compared to n-3 PUFA. Conclusions: Our findings reveal that AA has a dominant effect on the regulation of lipogenic genes in adipocytes.

  12. Activation of protein kinase A and exchange protein directly activated by cAMP promotes adipocyte differentiation of human mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    Bingbing Jia

    Full Text Available Human mesenchymal stem cells are primary multipotent cells capable of differentiating into several cell types including adipocytes when cultured under defined in vitro conditions. In the present study we investigated the role of cAMP signaling and its downstream effectors, protein kinase A (PKA and exchange protein directly activated by cAMP (Epac in adipocyte conversion of human mesenchymal stem cells derived from adipose tissue (hMADS. We show that cAMP signaling involving the simultaneous activation of both PKA- and Epac-dependent signaling is critical for this process even in the presence of the strong adipogenic inducers insulin, dexamethasone, and rosiglitazone, thereby clearly distinguishing the hMADS cells from murine preadipocytes cell lines, where rosiglitazone together with dexamethasone and insulin strongly promotes adipocyte differentiation. We further show that prostaglandin I(2 (PGI(2 may fully substitute for the cAMP-elevating agent isobutylmethylxanthine (IBMX. Moreover, selective activation of Epac-dependent signaling promoted adipocyte differentiation when the Rho-associated kinase (ROCK was inhibited. Unlike the case for murine preadipocytes cell lines, long-chain fatty acids, like arachidonic acid, did not promote adipocyte differentiation of hMADS cells in the absence of a PPARγ agonist. However, prolonged treatment with the synthetic PPARδ agonist L165041 promoted adipocyte differentiation of hMADS cells in the presence of IBMX. Taken together our results emphasize the need for cAMP signaling in concert with treatment with a PPARγ or PPARδ agonist to secure efficient adipocyte differentiation of human hMADS mesenchymal stem cells.

  13. Adipocyte lipid synthesis coupled to neuronal control of thermogenic programming

    Directory of Open Access Journals (Sweden)

    Adilson Guilherme

    2017-08-01

    Conclusions: These results demonstrate that downregulation of fatty acid synthesis via FASN depletion in white adipocytes of mature mice can stimulate neuronal signaling to control thermogenic programming in iWAT.

  14. Form(ul)ation of adipocytes by lipids.

    Science.gov (United States)

    Lapid, Kfir; Graff, Jonathan M

    2017-07-03

    Lipids have the potential to serve as bio-markers, which allow us to analyze and to identify cells under various experimental settings, and to serve as a clinical diagnostic tool. For example, diagnosis according to specific lipids that are associated with diabetes and obesity. The rapid development of mass-spectrometry techniques enables identification and profiling of multiple types of lipid species. Together, lipid profiling and data interpretation forge the new field of lipidomics. Lipidomics can be used to characterize physiologic and pathophysiological processes in adipocytes, since lipid metabolism is at the core of adipocyte physiology and energy homeostasis. A significant bulk of lipids are stored in adipocytes, which can be released and used to produce energy, used to build membranes, or used as signaling molecules that regulate metabolism. In this review, we discuss how exhaust of lipidomes can be used to study adipocyte differentiation, physiology and pathophysiology.

  15. The emergence of cold-induced brown adipocytes in mouse white fat depots is determined predominantly by white to brown adipocyte transdifferentiation

    DEFF Research Database (Denmark)

    Barbatelli, G.; Murano, I.; Madsen, Lise

    2010-01-01

    The origin of brown adipocytes arising in white adipose tissue (WAT) after cold acclimatization is unclear. Here, we demonstrate that several UCP1-immunoreactive brown adipocytes occurring in WAT after cold acclimatization have a mixed morphology (paucilocular adipocytes). These cells also had...... for C/EBP (an antimitotic protein), whereas Ccna1 expression (related to cell proliferation) was unchanged. Overall, our data strongly suggest that the cold-induced emergence of brown adipocytes in WAT predominantly reflects ß3-adrenoceptor-mediated transdifferentiation....

  16. Reversing adipocyte differentiation: Implications for treatment of obesity

    OpenAIRE

    Zhou, Yan-Ting; Wang, Zhuo-Wei; Higa, Moritake; Newgard, Christopher B.; Unger, Roger H.

    1999-01-01

    Conventional treatment of obesity reduces fat in mature adipocytes but leaves them with lipogenic enzymes capable of rapid resynthesis of fat, a likely factor in treatment failure. Adenovirus-induced hyperleptinemia in normal rats results in rapid nonketotic fat loss that persists after hyperleptinemia disappears, whereas pair-fed controls regain their weight in 2 weeks. We report here that the hyperleptinemia depletes adipocyte fat while profoundly down-regulating lipogenic enzymes and their...

  17. Insulin-stimulated lipid accumulation is inhibited by ROS-scavenging chemicals, but not by the Drp1 inhibitor Mdivi-1.

    Science.gov (United States)

    Kim, Jung-Hak; Park, Sun-Ji; Kim, Bokyung; Choe, Young-Geun; Lee, Dong-Seok

    2017-01-01

    Adipocyte differentiation is regulated by intracellular reactive oxygen species (ROS) generation and mitochondrial fission and fusion processes. However, the correlation between intracellular ROS generation and mitochondrial remodeling during adipocyte differentiation is still unknown. Here, we investigated the effect on adipocyte differentiation of 3T3-L1 cells of intracellular ROS inhibition using N-acetyl cysteine (Nac) and Mito-TEMPO and of mitochondrial fission inhibition using Mdivi-1. Differentiated 3T3-L1 adipocytes displayed an increase in mitochondrial fission, ROS generation, and the expression of adipogenic and mitochondrial dynamics-related proteins. ROS scavenger (Nac or Mito-TEMPO) treatment inhibited ROS production, lipid accumulation, the expression of adipogenic and mitochondrial dynamics-related proteins, and mitochondrial fission during adipogenesis of 3T3-L1 cells. On the other hand, treatment with the mitochondrial fission inhibitor Mdivi-1 inhibited mitochondrial fission but did not inhibit ROS production, lipid accumulation, or the expression of adipogenic and mitochondrial dynamics-related proteins, with the exception of phosphorylated Drp1 (Ser616), in differentiated 3T3-L1 adipocytes. The inhibition of mitochondrial fission did not affect adipocyte differentiation, while intracellular ROS production decreased in parallel with inhibition of adipocyte differentiation. Therefore, our results indicated that ROS are an essential regulator of adipocyte differentiation in 3T3-L1 cells.

  18. Estimation of atorvastatin calcium and fenofibrate in tablets by derivative spectrophotometry and liquid chromatography.

    Science.gov (United States)

    Nakarani, Naresh V; Bhatt, Kashyap K; Patel, Rutva D; Bhatt, Hemaxi S

    2007-01-01

    Two simple and accurate methods to determine atorvastatin calcium (ATO) and fenofibrate (FEN) in combined dosage forms were developed using second-derivative spectrophotometry and reversed-phase liquid chromatography (LC). ATO and FEN in combined preparations (tablets) were quantitated using the second-derivative responses at 245.64 nm for ATO and 289.56 nm for FEN in spectra of their solution in methanol. The calibration curves were linear [correlation coefficient (r) = 0.9992 for ATO and 0.9995 for FEN] in the concentration range of 3-15 microg/mL for ATO and FEN. In the LC method, analysis was performed on a Hypersil ODS-C18 column (250 mm x 4.6 mm id, 5 microm particle size) in the isocratic mode using the mobile phase methanol-water (90 + 10, v/v), adjusted to pH 5.5 with orthophosphoric acid, at a flow rate of 1 mL/min. Measurement was made at a wavelength of 246.72 nm. Both drugs were well resolved on the stationary phase, and the retention times were 1.95 min for ATO and 5.50 min for FEN. The calibration curves were linear (r = 0.9985 for ATO and 0.9976 for FEN) in the concentration range of 3-15 microg/mL for ATO and FEN. Both methods were validated, and the results were compared statistically. They were found to be accurate, precise, and specific. The methods were successfully applied to the estimation of ATO and FEN in combined tablet formulations.

  19. Regional differences in adipocyte lactate production from glucose

    International Nuclear Information System (INIS)

    Newby, F.D.; Sykes, M.N.; DiGirolamo, M.

    1988-01-01

    Having shown that lactate is an important product of glucose metabolism by rat epididymal adipocytes, the authors investigated possible regional differences in adipocyte lactate production and the role of the animals' nutritional state and stage of development. [U- 14 C]glucose metabolism, lactate production, and response to insulin were measured in fat cells isolated from four adipose regions from young lean and older fatter rats, killed either in the fed state or after fasting for 48 h. In the absence of insulin, mesenteric fat cells from either age group metabolized significantly more glucose per cell and converted more glucose to lactate than cells from other depots, regardless of nutritional state. Adipocytes from fasted lean rats showed a significant increase in the relative glucose conversion to lactate in all depots when compared with cells from fed lean rats. Fasting of older fatter rats, however, had limited effects on the relative adipocyte glucose conversion to lactate since lactate production was already high. Mesenteric fat cells had the lowest relative response to insulin, possibly due to the high basal rate of glucose metabolism. These findings indicate that differences exist among adipose regions in the rates of glucose metabolism, lactate production and response to insulin. The anatomical location of the mesenteric adipose depot, coupled with a high metabolic rate and blood perfusion, suggests that mesenteric adipocytes may provide a unique and more direct contribution of metabolic substrates for hepatic metabolism than adipocytes from other depots

  20. Cannabidiol promotes browning in 3T3-L1 adipocytes.

    Science.gov (United States)

    Parray, Hilal Ahmad; Yun, Jong Won

    2016-05-01

    Recruitment of the brown-like phenotype in white adipocytes (browning) and activation of existing brown adipocytes are currently being investigated as a means to combat obesity. Thus, a wide variety of dietary agents that contribute to browning of white adipocytes have been identified. The present study was designed to investigate the effects of cannabidiol (CBD), a major nonpsychotropic phytocannabinoid of Cannabis sativa, on induction of browning in 3T3-L1 adipocytes. CBD enhanced expression of a core set of brown fat-specific marker genes (Ucp1, Cited1, Tmem26, Prdm16, Cidea, Tbx1, Fgf21, and Pgc-1α) and proteins (UCP1, PRDM16, and PGC-1α). Increased expression of UCP1 and other brown fat-specific markers contributed to the browning of 3T3-L1 adipocytes possibly via activation of PPARγ and PI3K. In addition, CBD increased protein expression levels of CPT1, ACSL, SIRT1, and PLIN while down-regulating JNK2, SREBP1, and LPL. These data suggest possible roles for CBD in browning of white adipocytes, augmentation of lipolysis, thermogenesis, and reduction of lipogenesis. In conclusion, the current data suggest that CBD plays dual modulatory roles in the form of inducing the brown-like phenotype as well as promoting lipid metabolism. Thus, CBD may be explored as a potentially promising therapeutic agent for the prevention of obesity.

  1. Macrophage-secreted factors induce adipocyte inflammation and insulin resistance

    International Nuclear Information System (INIS)

    Permana, Paska A.; Menge, Christopher; Reaven, Peter D.

    2006-01-01

    Macrophage infiltration into adipose tissue increases with obesity, a condition associated with low-grade inflammation and insulin resistance. We investigated the direct effects of macrophage-secreted factors on adipocyte inflammation and insulin resistance. 3T3-L1 adipocytes incubated with media conditioned by RAW264.7 macrophages (RAW-CM) showed dramatically increased transcription of several inflammation-related genes, greater nuclear factor kappa B (NF-κB) activity, and enhanced binding of U937 monocytes. All of these effects were prevented by co-incubation with pyrrolidinedithiocarbamate, an NF-κB inhibitor. Adipocytes incubated with RAW-CM also released more non-esterified fatty acids and this increased lipolysis was not suppressed by insulin. In addition, RAW-CM treatment decreased insulin-stimulated glucose uptake in adipocytes. Taken together, these results indicate that macrophage-secreted factors induce inflammatory responses and reduce insulin responsiveness in adipocytes. These effects of macrophage-secreted factors on adipocytes may contribute significantly to the systemic inflammation and insulin resistance associated with obesity

  2. Global transcriptome profiling identifies KLF15 and SLC25A10 as modifiers of adipocytes insulin sensitivity in obese women.

    Directory of Open Access Journals (Sweden)

    Agné Kulyté

    Full Text Available Although the mechanisms linking obesity to insulin resistance (IR and type 2 diabetes (T2D are not entirely understood, it is likely that alterations of adipose tissue function are involved. The aim of this study was to identify new genes controlling insulin sensitivity in adipocytes from obese women with either insulin resistant (OIR or sensitive (OIS adipocytes. Insulin sensitivity was first determined by measuring lipogenesis in isolated adipocytes from abdominal subcutaneous white adipose tissue (WAT in a large observational study. Lipogenesis was measured under conditions where glucose transport was the rate limiting step and reflects in vivo insulin sensitivity. We then performed microarray-based transcriptome profiling on subcutaneous WAT specimen from a subgroup of 9 lean, 21 OIS and 18 obese OIR women. We could identify 432 genes that were differentially expressed between the OIR and OIS group (FDR ≤5%. These genes are enriched in pathways related to glucose and amino acid metabolism, cellular respiration, and insulin signaling, and include genes such as SLC2A4, AKT2, as well as genes coding for enzymes in the mitochondria respiratory chain. Two IR-associated genes, KLF15 encoding a transcription factor and SLC25A10 encoding a dicarboxylate carrier, were selected for functional evaluation in adipocytes differentiated in vitro. Knockdown of KLF15 and SLC25A10 using siRNA inhibited insulin-stimulated lipogenesis in adipocytes. Transcriptome profiling of siRNA-treated cells suggested that KLF15 might control insulin sensitivity by influencing expression of PPARG, PXMP2, AQP7, LPL and genes in the mitochondrial respiratory chain. Knockdown of SLC25A10 had only modest impact on the transcriptome, suggesting that it might directly influence insulin sensitivity in adipocytes independently of transcription due to its important role in fatty acid synthesis. In summary, this study identifies novel genes associated with insulin sensitivity in

  3. Testosterone regulates 3T3-L1 pre-adipocyte differentiation and epididymal fat accumulation in mice through modulating macrophage polarization.

    Science.gov (United States)

    Ren, Xiaojiao; Fu, Xiaojian; Zhang, Xinhua; Chen, Shiqiang; Huang, Shuguang; Yao, Lun; Liu, Guoquan

    2017-09-15

    Low testosterone levels are strongly related to obesity in males. The balance between the classically M1 and alternatively M2 polarized macrophages also plays a critical role in obesity. It is not clear whether testosterone regulates macrophage polarization and then affects adipocyte differentiation. In this report, we demonstrate that testosterone strengthens interleukin (IL) -4-induced M2 polarization and inhibits lipopolysaccharide (LPS)-induced M1 polarization, but has no direct effect on adipocyte differentiation. Cellular signaling studies indicate that testosterone regulates macrophage polarization through the inhibitory regulative G-protein (Gαi) mainly, rather than via androgen receptors, and phosphorylation of Akt. Moreover, testosterone inhibits pre-adipocyte differentiation induced by M1 macrophage medium. Lowering of serum testosterone in mice by injecting a luteinizing hormone receptor (LHR) peptide increases epididymal white adipose tissue. Testosterone supplementation reverses this effect. Therefore, our findings indicate that testosterone inhibits pre-adipocyte differentiation by switching macrophages to M2 polarization through the Gαi and Akt signaling pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Prevention of diet-induced obesity by apple polyphenols in Wistar rats through regulation of adipocyte gene expression and DNA methylation patterns.

    Science.gov (United States)

    Boqué, Noemi; de la Iglesia, Rocío; de la Garza, Ana L; Milagro, Fermín I; Olivares, Mónica; Bañuelos, Oscar; Soria, Ana Cristina; Rodríguez-Sánchez, Sonia; Martínez, José Alfredo; Campión, Javier

    2013-08-01

    This study was conducted to determine the mechanisms implicated in the beneficial effects of apple polyphenols (APs) against diet-induced obesity in Wistar rats, described in a previous study from our group. Supplementation of high-fat sucrose diet with AP prevented adiposity increase by inhibition of adipocyte hypertrophy. Rats supplemented with AP exhibited improved glucose tolerance while adipocytes isolated from these rats showed an enhanced lipolytic response to isoproterenol. AP intake led to reduced Lep, Plin, and sterol regulatory element binding transcription factor 1 (Srebf1) mRNA levels and increased aquaporin 7 (Aqp7), adipocyte enhancer binding protein 1 (Aebp1), and peroxisome proliferator-activated receptor gamma co-activator 1 alpha (Ppargc1a) mRNA levels in epididymal adipocytes. In addition, we found different methylation patterns of Aqp7, Lep, Ppargc1a, and Srebf1 promoters in adipocytes from apple-supplemented rats compared to high-fat sucrose fed rats. The administration of AP protects against body weight gain and fat deposition and improves glucose tolerance in rats. We propose that AP exerts the antiobesity effects through the regulation of genes involved in adipogenesis, lipolysis, and fatty acid oxidation, in a process that could be mediated in part by epigenetic mechanisms. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The inflammatory receptor CD40 is expressed on human adipocytes: contribution to crosstalk between lymphocytes and adipocytes.

    Science.gov (United States)

    Poggi, M; Jager, J; Paulmyer-Lacroix, O; Peiretti, F; Gremeaux, T; Verdier, M; Grino, M; Stepanian, A; Msika, S; Burcelin, R; de Prost, D; Tanti, J F; Alessi, M C

    2009-06-01

    Obesity is associated with adipose tissue inflammation. The CD40 molecule, TNF receptor superfamily member 5 (CD40)/CD40 ligand (CD40L) pathway plays a role in the onset and maintenance of the inflammatory reaction, but has not been studied in human adipose tissue. Our aim was to examine CD40 expression by human adipocytes and its participation in adipose tissue inflammation. CD40 expression was investigated in human whole adipose tissue and during adipocyte differentiation by real-time PCR, Western blot and immunohistochemistry. The CD40/CD40L pathway was studied using recombinant CD40L (rCD40L) in adipocyte culture and neutralising antibodies in lymphocyte/adipocyte co-culture. CD40 mRNA levels in subcutaneous adipose tissue were higher in the adipocyte than in the stromal-vascular fraction. CD40 expression was upregulated during adipocyte differentiation. Addition of rCD40L to adipocytes induced mitogen activated protein kinase (MAPK) activation, stimulated inflammatory adipocytokine production, and decreased insulin-induced glucose transport in parallel with a downregulation of IRS1 and GLUT4 (also known as SCL2A4). rCD40L decreased the expression of lipogenic genes and increased lipolysis. CD40 mRNA levels were significantly higher in subcutaneous adipose tissue than in visceral adipose tissue of obese patients and were positively correlated with BMI, and with IL6 and leptin mRNA levels. Lymphocyte/adipocyte co-culture led to an upregulation of proinflammatory adipocytokines and a downregulation of leptin and adiponectin. Physical separation of the two cell types attenuated these effects, suggesting the involvement of a cell-cell contact. Blocking the CD40/CD40L interaction with neutralising antibodies reduced IL-6 secretion from adipocytes. Adipocyte CD40 may contribute to obesity-related inflammation and insulin resistance. T lymphocytes regulate adipocytokine production through both the release of soluble factor(s) and heterotypic contact with adipocytes

  6. In Vitro Lipolysis Data Does Not Adequately Predict the In Vivo Performance of Lipid-Based Drug Delivery Systems Containing Fenofibrate

    DEFF Research Database (Denmark)

    Thomas, Nicky; Richter, Katharina; Pedersen, Thomas B

    2014-01-01

    on identical self-nanoemulsifying drug delivery systems (SNEDDS) containing 200 mg of fenofibrate, either dissolved or suspended, were subjected to combined gastric (pH 2) and intestinal (pH 6.5) in vitro lipolysis. Based on the solubilization profiles and SRM the rank-order SNEDDS (75% drug load) > super...

  7. Genetic Variants in HSD17B3, SMAD3, and IPO11 Impact Circulating Lipids in Response to Fenofibrate in Individuals With Type 2 Diabetes.

    Science.gov (United States)

    Rotroff, Daniel M; Pijut, Sonja S; Marvel, Skylar W; Jack, John R; Havener, Tammy M; Pujol, Aurora; Schluter, Agatha; Graf, Gregory A; Ginsberg, Henry N; Shah, Hetal S; Gao, He; Morieri, Mario-Luca; Doria, Alessandro; Mychaleckyi, Josyf C; McLeod, Howard L; Buse, John B; Wagner, Michael J; Motsinger-Reif, Alison A

    2018-04-01

    Individuals with type 2 diabetes (T2D) and dyslipidemia are at an increased risk of cardiovascular disease. Fibrates are a class of drugs prescribed to treat dyslipidemia, but variation in response has been observed. To evaluate common and rare genetic variants that impact lipid responses to fenofibrate in statin-treated patients with T2D, we examined lipid changes in response to fenofibrate therapy using a genomewide association study (GWAS). Associations were followed-up using gene expression studies in mice. Common variants in SMAD3 and IPO11 were marginally associated with lipid changes in black subjects (P < 5 × 10 -6 ). Rare variant and gene expression changes were assessed using a false discovery rate approach. AKR7A3 and HSD17B13 were associated with lipid changes in white subjects (q < 0.2). Mice fed fenofibrate displayed reductions in Hsd17b13 gene expression (q < 0.1). Associations of variants in SMAD3, IPO11, and HSD17B13, with gene expression changes in mice indicate that transforming growth factor-beta (TGF-β) and NRF2 signaling pathways may influence fenofibrate effects on dyslipidemia in patients with T2D. © 2017 American Society for Clinical Pharmacology and Therapeutics.

  8. Development of self-nanoemulsifying drug delivery systems for the enhancement of solubility and oral bioavailability of fenofibrate, a poorly water-soluble drug

    Directory of Open Access Journals (Sweden)

    Moshin K

    2016-06-01

    Full Text Available Kazi Mohsin,1 Rayan Alamri,1 Ajaz Ahmad,2 Mohammad Raish,3 Fars K Alanazi,1 Muhammad Delwar Hussain4 1Kayyali Chair for Pharmaceutical Industry, Department of Pharmaceutics, 2Department of Clinical Pharmacy, 3Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; 4Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, California Health Science University, Clovis, CA, USA Background: Self-nanoemulsifying drug delivery systems (SNEDDS have become a popular formulation option as nanocarriers for poorly water-soluble drugs. The objective of this study was to investigate the factor that can influence the design of successful lipid formulation classification system (LFCS Type III SNEDDS formulation and improve the oral bioavailability (BA of fenofibrate. Materials and methods: LFCS Type III SNEDDS were designed using various oils, water-soluble surfactants, and/or cosolvents (in considering the polarity of the lipids for the model anticholesterol drug, fenofibrate. The developed SNEDDS were assessed visually and by measurement of the droplet size. Equilibrium solubility of fenofibrate in the SNEDDS was conducted to find out the maximum drug loading. Dynamic dispersion studies were carried out (1/100 dilution in water to investigate how much drug stays in solution after aqueous dispersion of the formulation. The BA of SNEDDS formulation was evaluated in the rat. Results: The results from the characterization and solubility studies showed that formulations containing mixed glycerides were highly efficient SNEDDS as they had higher solubility of the drug and produced nanosized droplets. The dispersion studies confirmed that SNEDDS (containing polar mixed glycerides can retain >98% drug in solution for >24 hours in aqueous media. The in vivo pharmacokinetics parameters of SNEDDS formulation in comparison with pure drug showed significant increase in Cmax and AUC0–t, ~78% and 67%, respectively

  9. Processing of growth hormone by rat adipocytes in primary culture: differentiation between release of intact hormone and degradative processing.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1987-10-01

    Rat adipocytes in primary culture have been used to study the intracellular processing of GH. These classic target cells for GH have been shown to process GH through two pathways: a nondegradative pathway which resulted in the rapid release of intact GH, and a slower, degradative pathway which involved the degradation of GH and release of degraded ligand. Differentiation between the two pathways was on the basis of differences in their kinetics and temperature dependence. The present study has investigated the relative characteristics of the two pathways further. Incubation of [125I]human GH ([125I]hGH)-preloaded adipocytes with extracellular unlabeled hGH (400 ng/ml) resulted in an increase in the absolute amount of [125I]hGH released. The increased amount of [125I]hGH released was all intact. Extracellular, unlabeled hGH had no effect on the rate or amount of degraded [125I]hGH released. This suggests that the nondegradative pathway is sensitive to the number of internalized hormone-receptor complexes and that GH which is not immediately degraded or stored in the degradative pathway, is redirected and processed via the faster non-degradative pathway. Ammonium chloride (known to inhibit the lysosomal degradation of many polypeptide hormones) markedly inhibited the absolute amount of [125I]hGH released from preloaded adipocytes. This inhibition was due to an effect on the release of degraded [125I]hGH. NH4Cl had no effect on the rate or amount of intact [125I]hGH released. Finally, it was found that dinitrophenol and sodium fluoride (agents known to deplete cellular energy) inhibited the release of degraded GH but not intact GH suggesting that the degradative pathway involves an energy-dependent step, most likely the fusion of hormone-containing vesicles with the lysosomal membrane. The mechanism of release of intact hormone by energy-independent means is not yet known. These data indicate that the processing of GH by cultured rat adipocytes is complex and involves

  10. Oxidation by-products and ecotoxicity assessment during the photodegradation of fenofibric acid in aqueous solution with UV and UV/H{sub 2}O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Santiago, Javier [Department of Chemical Engineering, University of Alcala, E-28771 Alcala de Henares (Spain); Agueera, Ana; Mar Gomez-Ramos, Maria del [Department of Analytical Chemistry, University of Almeria, E-04010 Almeria (Spain); Fernandez Alba, Amadeo R. [Department of Analytical Chemistry, University of Almeria, E-04010 Almeria (Spain); Advanced Study Institute of Madrid, IMDEA-Agua, Parque Cientifico Tecnologico, E-28805 Alcala de Henares, Madrid (Spain); Garcia-Calvo, Eloy [Department of Chemical Engineering, University of Alcala, E-28771 Alcala de Henares (Spain); Advanced Study Institute of Madrid, IMDEA-Agua, Parque Cientifico Tecnologico, E-28805 Alcala de Henares, Madrid (Spain); Rosal, Roberto, E-mail: roberto.rosal@uah.es [Department of Chemical Engineering, University of Alcala, E-28771 Alcala de Henares (Spain); Advanced Study Institute of Madrid, IMDEA-Agua, Parque Cientifico Tecnologico, E-28805 Alcala de Henares, Madrid (Spain)

    2011-10-30

    Highlights: {yields} UV and UV/H{sub 2}O{sub 2} photolysis of fenofibric acid. {yields} Identification of reaction intermediates using exact mass measurements. {yields} UV/H{sub 2}O{sub 2} removed toxicity towards Pseudokirchneriella subcapitata. {yields} Irradiated samples contain a number of chlorinated products. - Abstract: The degradation of an aqueous solution of fenofibric acid was investigated using ultraviolet (UV) photolysis and UV/H{sub 2}O{sub 2} with a low-pressure mercury lamp. We obtained quantum yields at different temperatures and the rate constant for the reaction of fenofibric acid with hydroxyl radicals. The maximum radical exposure per fluence ratio obtained was 1.4 x 10{sup -10} M L{sup -1} mW{sup -1}. Several reaction intermediates were detected by means of exact mass measurements performed by liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-ESI-QTOF-MS). UV and UV/H{sub 2}O{sub 2} pathways involve the decarboxylation of fenofibric acid to 4-chloro-4'-(1-hydroxy-1-methylethyl)benzophenone and other minor products, predominantly chlorinated aromatics. We detected several intermediates from reactions with hydroxyl radicals and some lower molecular weight products from the scission of the carbonyl carbon-to-aromatic-carbon bond. We recorded high toxicity in UV irradiated samples for the growth of Pseudokirchneriella subcapitata even after the total depletion of fenofibric acid; this was probably due to the presence of chlorinated aromatics. A degree of toxicity reappeared in highly irradiated UV/H{sub 2}O{sub 2} samples, probably because of the formation of ring-opening products. The degree of mineralization was closely related to that of dechlorination and reached values of over 50% after 3-4 min before stabilizing thereafter.

  11. Conventional kinesin KIF5B mediates adiponectin secretion in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Ju, E-mail: juzi.cui@gmail.com [The Key Laboratory of Geriatrics, Beijing Hospital and Beijing Institute of Geriatrics, Beijing (China); Pang, Jing; Lin, Ya-Jun; Jiang, Ping; Gong, Huan [The Key Laboratory of Geriatrics, Beijing Hospital and Beijing Institute of Geriatrics, Beijing (China); Wang, Zai [Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing (China); Li, Jian; Cai, Jian-Ping [The Key Laboratory of Geriatrics, Beijing Hospital and Beijing Institute of Geriatrics, Beijing (China); Huang, Jian-Dong, E-mail: jdhuang@hku.hk [School of Biomedical Sciences and Shenzhen Institute of Research and Innovation, The University of Hong Kong, Pokfulam (Hong Kong); The Centre for Synthetic Biology Engineering Research, Shenzhen Institutes of Advanced Technology, Shenzhen (China); Zhang, Tie-Mei, E-mail: tmzhang126@126.com [The Key Laboratory of Geriatrics, Beijing Hospital and Beijing Institute of Geriatrics, Beijing (China)

    2016-08-05

    Insulin stimulates adiponectin secretion and glucose transporter type 4 (GLUT4) translocation in adipocyte to regulate metabolism homeostasis. Similar to GLUT4 translocation, intracellular trafficking and release of adiponectin in adipocytes relies on the trans-Golgi network and endosomal system. Recent studies show that the heavy chain of conventional kinesin (KIF5B) mediates GLUT4 translocation in murine 3T3-L1 adipocytes, however, the motor machinery involved in mediating intracellular trafficking and release of adiponectin is unknown. Here, we examined the role of KIF5B in the regulation of adiponectin secretion. The KIF5B level was up-regulated during 3T3-L1 adipogenesis. This increase in cytosolic KIF5B was synchronized with the induction of adiponectin. Endogenous KIF5B and adiponectin were partially colocalized at the peri-nuclear and cytosolic regions. In addition, adiponectin-containing vesicles were co-immunoprecipitated with KIF5B. Knockdown of KIF5B resulted in a marked inhibition of adiponectin secretion and overexpression of KIF5B enhanced adiponectin release, whereas leptin secretion was not affected by changes in KIF5B expression. These data suggest that the secretion of adiponectin, but not leptin, is dependent on functional KIF5B. - Highlights: • The KIF5B level was up regulated during 3T3-L1 adipogenesis. • Endogenous KIF5B and adiponectin were partially colicalized. • Adiponectin-containing vesicles were co-immunoprecipitated with KIF5B. • The secretion of adiponectin, but not leptin, is dependent on functional KIF5B.

  12. AdipoCount: A New Software for Automatic Adipocyte Counting

    Directory of Open Access Journals (Sweden)

    Xuhao Zhi

    2018-02-01

    Full Text Available Obesity has spread worldwide and become a common health problem in modern society. One typical feature of obesity is the excessive accumulation of fat in adipocytes, which occurs through the following two physiological phenomena: hyperplasia (increase in quantity and hypertrophy (increase in size of adipocytes. In clinical and scientific research, the accurate quantification of the number and diameter of adipocytes is necessary for assessing obesity. In this study, we present a new automatic adipocyte counting system, AdipoCount, which is based on image processing algorithms. Comparing with other existing adipocyte counting tools, AdipoCount is more accurate and supports further manual correction. AdipoCount counts adipose cells by the following three-step process: (1 It detects the image edges, which are used to segment the membrane of adipose cells; (2 It uses a watershed-based algorithm to re-segment the missing dyed membrane; and (3 It applies a domain connectivity analysis to count the cells. The outputs of this system are the labels and the statistical data of all adipose cells in the image. The AdipoCount software is freely available for academic use at: http://www.csbio.sjtu.edu.cn/bioinf/AdipoCount/.

  13. Silibinin regulates lipid metabolism and differentiation in functional human adipocytes

    Directory of Open Access Journals (Sweden)

    Ignazio eBarbagallo

    2016-01-01

    Full Text Available Silibinin, a natural plant flavonoid, is the main active constituent found in milk thistle (Silybum marianum. It is known to have hepatoprotective, anti-neoplastic effect and suppresses lipid accumulation in adipocytes. Objective of this study was to investigate the effect of silibinin on adipogenic differentiation and thermogenic capacity of human adipose tissue derived mesenchymal stem cells. Silibinin (10 μM treatment, either at the beginning or at the end of adipogenic differentiation, resulted in an increase of SIRT-1, PPARα, Pgc-1α and UCPs gene expression. Moreover, silibinin administration resulted in a decrease of PPARγ, FABP4, FAS and MEST/PEG1 gene expression during the differentiation, confirming that this compound is able to reduce fatty acid accumulation and adipocyte size. Our data showed that silibinin regulated adipocyte lipid metabolism, inducing thermogenesis and promoting a brown remodelling in adipocyte. Taken together, our findings suggest that silibinin increases UCPs expression by stimulation of SIRT1, PPARα and Pgc-1α, improved metabolic parameters, decreased lipid mass leading to the formation of functional adipocytes.

  14. Multiple intracellular signaling pathways orchestrate adipocytic differentiation of human bone marrow stromal stem cells

    DEFF Research Database (Denmark)

    Ayesh Hafez Ali, Dalia; Abuelreich, Sarah; Alkeraishan, Nora

    2018-01-01

    Bone marrow adipocyte formation plays a role in bone homeostasis and whole body energy metabolism. However, the transcriptional landscape and signaling pathways associated with adipocyte lineage commitment and maturation are not fully delineated. Thus, we performed global gene expression profilin...

  15. Growth hormone maintains its own receptors in rat adipocytes.

    Science.gov (United States)

    Grichting, G; Goodman, H M

    1986-08-01

    Hypophysectomy decreased the capacity of adipocytes isolated from epididymal fat to bind [125I]human GH [( 125I]hGH) specifically without changing the apparent affinity for hGH. Specific binding of hGH by adipocytes of both normal and hypophysectomized rats appeared saturated when incubated with 75-80 ng/ml or higher concentrations of GH regardless of whether binding was studied for 2 h at 37 C or for 16 h at 0 C. Maximum binding of hGH by normal adipocytes was approximately 0.45 ng/10(6) cells, and that by adipocytes of hypophysectomized rats ranged from 0.15-0.25 ng/10(6) cells. In cells of both normal and hypophysectomized rats, only 25-30% of the hormone specifically bound at 37 was removed by digestion with trypsin, and about 75% was displaced by incubation with 5 M magnesium chloride, suggesting that these adipocytes internalized a significant fraction of bound hormone and that hypophysectomy did not alter the extent of internalization. Previously bound hormone was lost from normal adipocytes with a half-time of about 32 min and from adipocytes of hypophysectomized rats with a half-time of about 45 min, suggesting that hypophysectomy slowed the rate of processing bound hormone. To determine which pituitary hormone(s) might be required to maintain GH binding, we measured the binding of [125I]hGH at 3 or 30 ng/ml by fat cells prepared from hypophysectomized rats after various treatment regimens. Administration of bovine GH ip at a dose of 10 micrograms/rat every 4 h for 24 h doubled the binding of [125I]hGH by adipocytes prepared 4 h after the last injection. Similar results were obtained in fat cells examined 4 h after only one injection of 60 micrograms bovine GH to rats hypophysectomized 2-4 weeks previously. When binding was measured 16-24 h after GH administration, there was no apparent effect on restoration of binding even after treatment with 100 micrograms GH/day for up to 6 days, suggesting that the effects of GH in maintaining receptor number are

  16. Ononitol monohydrate enhances PRDM16 & UCP-1 expression, mitochondrial biogenesis and insulin sensitivity via STAT6 and LTB4R in maturing adipocytes.

    Science.gov (United States)

    Subash-Babu, P; Alshatwi, Ali A

    2018-03-01

    Ononitol monohydrate (OMH), a glycoside was originally isolated from Cassia tora (Linn.). Glycosides regulate lipid metabolism but scientific validation desired. Hence, we aimed to evaluate the effect of OMH on enhancing mitochondrial potential, mitochondrial biogenesis, upregulate the expression of brown adipogenesis specific genes in maturing adipocytes. In addition, we observed the inter-relation between adipocyte and T-lymphocyte; whether, OMH treated adipocyte-condition medium stimulate T-cell chemokine linked with insulin resistance. In a dose dependent manner OMH treated to preadipocyte significantly inhibited maturation and enhanced mitochondrial biogenesis, it was confirmed by Oil red 'O and Nile red stain without inducing cytotoxicity. The mRNA levels of adipocyte browning related genes such as, PR domain containing 16 (PRDM16), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PPARγC1α) and uncoupling protein-1 (UCP-1) have been significantly upregulated. In addition, adipogenic transcription factors [such as proliferator activated receptor γ (PPARγ), CCAAT/enhancer binding protein (C/EBPα) and sterol regulatory element binding protein-1c (SREBP-1c)] and adipogenic genes were significantly down-regulated by treatment with OMH when compared to control cells. Protein expression levels of adiponectin have been increased; leptin, C/EBPα and leukotriene B4 receptor (LTB4R) were down regulated by OMH in mature adipocytes. In addition, adipocyte condition medium and OMH treated T-lymphocyte, significantly increased insulin signaling pathway related mRNAs, such as interlukin-4 (IL-4), signal transducer and activator of transcription 6 (STAT 6 ) and decreased leukotriene B4 (LTB 4 ). The present findings suggest that OMH increased browning factors in differentiating and maturing preadipocyte also decreased adipose tissue inflammation as well as the enhanced insulin signaling. Copyright © 2018. Published by Elsevier Masson SAS.

  17. Stinging Nettle (Urtica dioica L.) Attenuates FFA Induced Ceramide Accumulation in 3T3-L1 Adipocytes in an Adiponectin Dependent Manner.

    Science.gov (United States)

    Obanda, Diana N; Zhao, Peng; Richard, Allison J; Ribnicky, David; Cefalu, William T; Stephens, Jacqueline M

    2016-01-01

    Excess dietary lipids result in the accumulation of lipid metabolites including ceramides that can attenuate insulin signaling. There is evidence that a botanical extract of Urtica dioica L. (stinging nettle) improves insulin action, yet the precise mechanism(s) are not known. Hence, we examined the effects of Urtica dioica L. (UT) on adipocytes. We investigated the effects of an ethanolic extract of UT on free fatty acid (palmitic acid) induced inhibition of insulin-stimulated Akt serine phosphorylation and modulation of ceramidase expression in 3T3-L1 adipocytes. Adipocytes were exposed to excess FFAs in the presence or absence of UT. Effects on adiponectin expression, ceramidase expression, ceramidase activity, ceramide accumulation and insulin signaling were determined. As expected, FFAs reduced adiponectin expression and increased the expression of ceramidase enzymes but not their activity. FFA also induced the accumulation of ceramides and reduced insulin-stimulated phosphorylation of Akt in adipocytes. The effects of FFA were partially reversed by UT. UT enhanced adiponectin expression and ceramidase activity in the presence of excess FFAs. UT abated ceramide accumulation and increased insulin sensitivity via enhanced Akt phosphorylation. A siRNA knockdown of adiponectin expression prevented UT from exerting positive effects on ceramidase activity but not Akt phosphorylation. In adipocytes, the ability of UT to antagonize the negative effects of FFA by modulating ceramidase activity and ceramide accumulation is dependent on the presence of adiponectin. However, the ability of UT to enhance Akt phosphorylation is independent of adiponectin expression. These studies demonstrate direct effects of UT on adipocytes and suggest this botanical extract is metabolically beneficial.

  18. Stinging Nettle (Urtica dioica L. Attenuates FFA Induced Ceramide Accumulation in 3T3-L1 Adipocytes in an Adiponectin Dependent Manner.

    Directory of Open Access Journals (Sweden)

    Diana N Obanda

    Full Text Available Excess dietary lipids result in the accumulation of lipid metabolites including ceramides that can attenuate insulin signaling. There is evidence that a botanical extract of Urtica dioica L. (stinging nettle improves insulin action, yet the precise mechanism(s are not known. Hence, we examined the effects of Urtica dioica L. (UT on adipocytes.We investigated the effects of an ethanolic extract of UT on free fatty acid (palmitic acid induced inhibition of insulin-stimulated Akt serine phosphorylation and modulation of ceramidase expression in 3T3-L1 adipocytes. Adipocytes were exposed to excess FFAs in the presence or absence of UT. Effects on adiponectin expression, ceramidase expression, ceramidase activity, ceramide accumulation and insulin signaling were determined.As expected, FFAs reduced adiponectin expression and increased the expression of ceramidase enzymes but not their activity. FFA also induced the accumulation of ceramides and reduced insulin-stimulated phosphorylation of Akt in adipocytes. The effects of FFA were partially reversed by UT. UT enhanced adiponectin expression and ceramidase activity in the presence of excess FFAs. UT abated ceramide accumulation and increased insulin sensitivity via enhanced Akt phosphorylation. A siRNA knockdown of adiponectin expression prevented UT from exerting positive effects on ceramidase activity but not Akt phosphorylation.In adipocytes, the ability of UT to antagonize the negative effects of FFA by modulating ceramidase activity and ceramide accumulation is dependent on the presence of adiponectin. However, the ability of UT to enhance Akt phosphorylation is independent of adiponectin expression. These studies demonstrate direct effects of UT on adipocytes and suggest this botanical extract is metabolically beneficial.

  19. 4-hydroxynonenal causes impairment of human subcutaneous adipogenesis and induction of adipocyte insulin resistance.

    Science.gov (United States)

    Elrayess, Mohamed A; Almuraikhy, Shamma; Kafienah, Wael; Al-Menhali, Afnan; Al-Khelaifi, Fatima; Bashah, Moataz; Zarkovic, Kamelija; Zarkovic, Neven; Waeg, Georg; Alsayrafi, Mohammed; Jaganjac, Morana

    2017-03-01

    Increased adipose production of 4-hydroxynonenal (4-HNE), a bioreactive aldehyde, directly correlates with obesity and insulin resistance. The aim of this study was to elucidate the impact of 4-HNE in mediating adipocyte differentiation and function in two metabolically distinct obese groups; the insulin sensitive (IS) and the insulin resistant (IR). Subcutaneous (SC) adipose tissues were obtained from eighteen clinically well characterized obese premenopausal women undergoing weight reduction surgery. Cellular distribution of 4-HNE in the form of protein adducts was determined by immunohistochemistry in addition to its effect on oxidative stress, cell growth, adipogenic capacity and insulin signaling in preadipocytes derived from the IS and IR participants. 4-HNE was detected in the SC adipose tissue in different cell types with the highest level detected in adipocytes and blood vessels. Short and long-term in vitro treatment of SC preadipocytes with 4-HNE caused inhibition of their growth and increased production of reactive oxygen species (ROS) and antioxidant enzymes. Repeated 4-HNE treatment led to a greater reduction in the adipogenic capacity of preadipocytes from IS subjects compared to IR and caused dephosphorylation of IRS-1 and p70S6K while activating GSK3α/β and BAD, triggering an IR phenotype. These data suggest that 4-HNE-induced oxidative stress plays a role in the regulation of preadipocyte growth, differentiation and insulin signaling and may therefore contribute to adipose tissue metabolic dysfunction associated with insulin resistance. Copyright © 2017. Published by Elsevier Inc.

  20. Inflammation Downregulates UCP1 Expression in Brown Adipocytes Potentially via SIRT1 and DBC1 Interaction

    Directory of Open Access Journals (Sweden)

    Mark K. Nøhr

    2017-05-01

    Full Text Available Brown adipose tissue thermogenesis at the cost of energy is not only important for the development of obesity, but also possesses great promise in anti-obesity treatment. Uncoupling protein 1 (UCP1 expression has been reported to be under control of the intracellular deacetylase SIRT1. Here, we investigated the effect and mechanism of inflammation and sirtuin-1 (SIRT1 activation on the induction of thermogenic genes in immortalized brown adipocytes incubated with LPS or IL1β and mice with elevated inflammatory tone. In vitro stimulation of brown adipocytes with dibutyryl cyclic adenosine monophosthate (dbcAMP reduced the expression of deleted in breast cancer-1 (Dbc1 (SIRT1 inhibitor and increased the Ucp1 expression. Silencing of SIRT1 attenuated dbcAMP induction of Ucp1. In contrast, IL1β increased the expression of Dbc1 and greatly reduced the induction of Ucp1. Similarly, in vivo studies revealed decreased expression of Ucp1 in brown adipose tissue (BAT in mice chronically infused with LPS. Resveratrol, a known SIRT1 activator, partly rescued the Ucp1 downregulation by inflammation in both the cell cultures and mice. Here, we describe how the expression of Ucp1 in BAT is controlled via SIRT1 and is reduced under inflammation and can be rescued by SIRT1 activation by resveratrol. We suggest the reduced UCP1 expression under inflammation is mediated by the increased expression of DBC1, which inhibits SIRT1 activity.

  1. Insulin stimulates the tyrosine phosphorylation of a Mr = 160,000 glycoprotein in adipocyte plasma membranes

    International Nuclear Information System (INIS)

    Yu, K.T.; Khalaf, N.; Czech, M.P.

    1986-01-01

    In an attempt to identify putative substrates for the insulin receptor kinase, adipocyte plasma membranes were incubated with [γ- 32 P]ATP in the presence and absence of insulin. Insulin stimulates the tyrosine phosphorylation of its receptor β subunit but does not detectably alter the phosphorylation of other membrane proteins. In contrast, when plasma membranes from insulin-treated adipocytes are phosphorylated, the 32 P-labeling of a Mr=160,000 species (p160) and insulin receptor β subunit are markedly increased when compared to controls. p160 exhibits a rapid response (max. at 1 min) and high sensitivity (ED 50 = 2 x 10 -10 M) to insulin. The stimulatory effect of insulin on the phosphorylation of p160 is rapidly reversed following the addition of anti-insulin serum. Cold chase experiments indicate that insulin promotes the phosphorylation of p160 rather than inhibiting its dephosphorylation. p160 is a glycoprotein as evidenced by its adsorption to immobilized lectins and does not represent the insulin receptor precursor. The action of insulin on p160 tyrosine phosphorylation is mimicked by concanavalin A but not by EGF and other insulin-like agents such as hydrogen peroxide and vanadate. These results suggest that p160 tyrosine phosphorylation is an insulin receptor-mediated event and may participate in signalling by the insulin receptor

  2. Ebf1-Dependent Control of the Osteoblast and Adipocyte Lineages

    OpenAIRE

    Hesslein, David G. T.; Fretz, Jackie A.; Xi, Yougen; Nelson, Tracy; Zhou, Shoaming; Lorenzo, Joseph A.; Schatz, David G.; Horowitz, Mark C.

    2008-01-01

    Ebf1 is a transcription factor essential for B cell fate specification and function and important for the development of olfactory sensory neurons. We show here that Ebf1 also plays an important role in regulating osteoblast and adipocyte development in vivo. Ebf1 mRNA and protein is expressed in MSCs, in OBs at most stages of differentiation, and in adipocytes. Tibiae and femora from Ebf1−/− mice had a striking increase in all bone formation parameters examined including the number of OBs, o...

  3. Retinoic acid receptor signalling directly regulates osteoblast and adipocyte differentiation from mesenchymal progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Green, A.C. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia); Kocovski, P.; Jovic, T.; Walia, M.K. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Chandraratna, R.A.S. [IO Therapeutics, Inc., Santa Ana, CA 92705 (United States); Martin, T.J.; Baker, E.K. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia); Purton, L.E., E-mail: lpurton@svi.edu.au [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia)

    2017-01-01

    Low and high serum retinol levels are associated with increased fracture risk and poor bone health. We recently showed retinoic acid receptors (RARs) are negative regulators of osteoclastogenesis. Here we show RARs are also negative regulators of osteoblast and adipocyte differentiation. The pan-RAR agonist, all-trans retinoic acid (ATRA), directly inhibited differentiation and mineralisation of early osteoprogenitors and impaired the differentiation of more mature osteoblast populations. In contrast, the pan-RAR antagonist, IRX4310, accelerated differentiation of early osteoprogenitors. These effects predominantly occurred via RARγ and were further enhanced by an RARα agonist or antagonist, respectively. RAR agonists similarly impaired adipogenesis in osteogenic cultures. RAR agonist treatment resulted in significant upregulation of the Wnt antagonist, Sfrp4. This accompanied reduced nuclear and cytosolic β-catenin protein and reduced expression of the Wnt target gene Axin2, suggesting impaired Wnt/β-catenin signalling. To determine the effect of RAR inhibition in post-natal mice, IRX4310 was administered to male mice for 10 days and bones were assessed by µCT. No change to trabecular bone volume was observed, however, radial bone growth was impaired. These studies show RARs directly influence osteoblast and adipocyte formation from mesenchymal cells, and inhibition of RAR signalling in vivo impairs radial bone growth in post-natal mice. - Graphical abstract: Schematic shows RAR ligand regulation of osteoblast differentiation in vitro. RARγ antagonists±RARα antagonists promote osteoblast differentiation. RARγ and RARα agonists alone or in combination block osteoblast differentiation, which correlates with upregulation of Sfrp4, and downregulation of nuclear and cytosolic β-catenin and reduced expression of the Wnt target gene Axin2. Red arrows indicate effects of RAR agonists on mediators of Wnt signalling.

  4. Palmitate Antagonizes Wnt/Beta-catenin Signaling in 3T3-L1 Pre-adipocytes

    Science.gov (United States)

    Long chain saturated free fatty acids such as palmitate (PA) produce insulin resistance, endoplasmic reticulum stress, and apoptosis in mature adipocytes and pre-adipocytes. In pre-adipocytes, saturated free fatty acids also promote adipogenic induction in the presence of adipogenic hormones. Wnt/be...

  5. Lipid droplets hypertrophy : a crucial determining factor in insulin regulation by adipocytes

    NARCIS (Netherlands)

    Sanjabi, Bahram; Dashty Rahmatabady, Monireh; Ozcan, Behiye; Akbarkhanzadeh, Vishtaseb; Rahimi, Mehran; Vinciguerra, Manlio; van Rooij, Felix; Al-Lahham, Saad; Sheedfar, Fareeba; van Kooten, Theo G.; Spek, C. Arnold; Rowshani, Ajda T.; van der Want, Johannes; Klaassen, Rene; Sijbrands, Eric; Peppelenbosch, Maikel P.; Rezaee, Farhad

    2015-01-01

    Lipid droplets (LDs) hypertrophy in adipocytes is the main cause of energy metabolic system dysfunction, obesity and its afflictions such as T2D. However, the role of adipocytes in linking energy metabolic disorders with insulin regulation is unknown in humans. Human adipocytes constitutively

  6. Lipid droplets hypertrophy: a crucial determining factor in insulin regulation by adipocytes.

    NARCIS (Netherlands)

    Sanjabi, B.; Dashty, M.; Ozcan, B.; Akbarkhanzadeh, V.; Rahimi, M.; Vinciguerra, M.; Rooij, F. van; Al-Lahham, S.; Sheedfar, F.; Kooten, T.G. van; Spek, C.A.; Rowshani, A.T.; Want, J. van der; Klaassen, R.; Sijbrands, E.; Peppelenbosch, M.P.; Rezaee, F.

    2015-01-01

    Lipid droplets (LDs) hypertrophy in adipocytes is the main cause of energy metabolic system dysfunction, obesity and its afflictions such as T2D. However, the role of adipocytes in linking energy metabolic disorders with insulin regulation is unknown in humans. Human adipocytes constitutively

  7. The PPARalpha agonist, fenofibrate decreases levels of anorectic N-acylethanolamines in the small intestine of mice

    DEFF Research Database (Denmark)

    Diep, Thi Ai; Golbas, Golfam; Hansen, Harald S.

    2014-01-01

    contribute to the hyperphagic effect of dietary fat. Male C57BL/6 mice were fed with either chow (minced Altromin) (n=8 from Taconic and n=8 from Charles River) or chow mixed with supplemented 0.5 wt% Fenofibrate (n=8 from Taconic and n=8 from Charles River) for seven days, and intestinal levels of NAEs were...... measured by LC-MS as previously described (3,4). The levels of PEA and LEA were significantly decreased (23-64%) in both strain of mice , while the decrease in OEA only reached significance in Charles river mice. There was no difference in levels of anandamide in any strain of mice. This suggests...

  8. Simultaneous quantitative resolution of atorvastatin calcium and fenofibrate in pharmaceutical preparation by using derivative ratio spectrophotometry and chemometric calibrations.

    Science.gov (United States)

    Nagaraj; Vipul, Kalamkar; Rajshree, Mashru

    2007-04-01

    In the present work, five different spectrophotometric techniques for simultaneous determination of formulations containing atorvastatin calcium (ATOR) and fenofibrate (FENO) in various combinations are described. In ratio spectra derivative spectrophotometry, analytical signals were measured at wavelengths corresponding to either maximums or minimums for both drugs in first derivative spectra of ratio spectra obtained by using either spectrum as divisor. For the remaining four methods using chemometric techniques, namely, classical least squares (CLS), inverse least squares (ILS), principal component regression (PCR) and partial least squares (PLS), the calibrations were constructed by using the absorption data matrix corresponding to the concentration data matrix, with measurements in the range of 231 - 310 nm (Deltalambda = 1 nm) in their zero-order spectra. The linearity range was found to be 4 - 22 and 2 - 20 microg/ml for ATOR and FENO, respectively. The validity of the proposed methods was successfully assessed for analyses of both drugs in laboratory-prepared mixtures and in commercial tablet formulations.

  9. Ascorbic acid is a dose-dependent inhibitor of adipocyte differentiation, probably by reducing cAMP pool.

    Science.gov (United States)

    Rahman, Fryad; Al Frouh, Fadi; Bordignon, Benoit; Fraterno, Marc; Landrier, Jean-François; Peiretti, Franck; Fontes, Michel

    2014-01-01

    Ascorbic acid (AA) is the active component of vitamin C and antioxidant activity was long considered to be the primary molecular mechanism underlying the physiological actions of AA. We recently demonstrated that AA is a competitive inhibitor of adenylate cyclase, acting as a global regulator of intracellular cyclic adenosine monophosphate (cAMP) levels. Our study, therefore, aimed to determine new targets of AA that would account for its potential effect on signal transduction, particularly during cell differentiation. We demonstrated that AA is an inhibitor of pre-adipocyte cell line differentiation, with a dose-dependent effect. Additionally, we describe the impact of AA on the expression of genes involved in adipogenesis and/or the adipocyte phenotype. Moreover, our data suggest that treatment with AA partially reverses lipid accumulation in mature adipocytes. These properties likely reflect the function of AA as a global regulator of the cAMP pool, since an analog of AA without any antioxidant properties elicited the same effect. Additionally, we demonstrated that AA inhibits adipogenesis in OP9 mesenchymal cell line and drives the differentiation of this line toward osteogenesis. Finally, our data suggest that the intracellular transporter SVCT2 is involved in these processes and may act as a receptor for AA.

  10. Sulforaphane inhibits mitotic clonal expansion during adipogenesis through cell cycle arrest.

    Science.gov (United States)

    Choi, Kyeong-Mi; Lee, Youn-Sun; Sin, Dong-Mi; Lee, Seunghyun; Lee, Mi Kyeong; Lee, Yong-Moon; Hong, Jin-Tae; Yun, Yeo-Pyo; Yoo, Hwan-Soo

    2012-07-01

    Obesity is a risk factor for numerous metabolic disorders such as type 2 diabetes, hypertension, and coronary heart disease. Adipocyte differentiation is triggered by adipocyte hyperplasia, which leads to obesity. In this study, the inhibitory effect of sulforaphane, an isothiocyanate, on adipogenesis in 3T3-L1 cells was investigated. Sulforaphane decreased the accumulation of lipid droplets stained with Oil Red O and inhibited the elevation of triglycerides in the adipocytes (half-maximal inhibitory concentration = 7.3 µmol/l). The expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα), major transcription factors for adipocyte differentiation, was significantly reduced by sulforaphane. The major effects of sulforaphane on the inhibition of adipocyte differentiation occurred during the early stage of adipogenesis. Thus, the expression of C/EBPβ, an early-stage biomarker of adipogenesis, decreased in a concentration-dependent manner when the adipocytes were exposed to sulforaphane (0, 5, 10, and 20 µmol/l). The proliferation of adipocytes treated with 20 µmol/l sulforaphane for 24 and 48 h was also suppressed. These results indicate that sulforaphane may specifically affect mitotic clonal expansion to inhibit adipocyte differentiation. Sulforaphane arrested the cell cycle at the G(0)/G(1) phase, increased p27 expression, and decreased retinoblastoma (Rb) phosphorylation. Additionally, sulforaphane modestly decreased the phosphorylation of ERK1/2 and Akt. Our results indicate that the inhibition of early-stage adipocyte differentiation by sulforaphane may be associated with cell cycle arrest at the G(0)/G(1) phase through upregulation of p27 expression.

  11. Effect of glucocorticoids on the activity, expression and proximal promoter of type II deiodinase in rat brown adipocytes.

    Science.gov (United States)

    Martinez-deMena, Raquel; Calvo, Rosa-Maria; Garcia, Laura; Obregon, Maria Jesus

    2016-06-15

    Triiodothyronine (T3) is important for thermogenesis in brown adipose tissue (BAT). Type II deiodinase (DIO2) produces T3 required for intracellular needs in BAT. Brown adipocytes in culture require T3 for the adrenergic stimulation of DIO2. Glucocorticoids induce adipocyte differentiation (lipogenesis). We investigated the regulation of DIO2 activity, Dio2 mRNA and Dio2 promoter activity by glucocorticoids in primary cultures of rat brown adipocytes using dexamethasone (DEX) and hydrocortisone (HC). DEX and HC regulated the adrenergic stimulation of DIO2 activity in a dose- and time-dependent manner, inhibiting DIO2 activity at short treatment times and large doses (1-10 μM) and stimulating DIO2 at low HC doses (1-100 nM) and longer times (DEX). Insulin depletion reduced DIO2 activity but the response to glucocorticoids remained unchanged. DEX and HC inhibited basal DIO2 activity. DEX had no effect on DIO2 half-life, whereas HC stabilized DIO2 activity. DEX and HC inhibited the adrenergic stimulation of Dio2 mRNA expression (100-10000 nM, 14-96 h), but stabilized Dio2 mRNA, particularly DEX. DEX increased basal Dio2 mRNA levels, possibly through stabilization of Dio2 mRNA. An 807 bp construct of the murine Dio2 proximal promoter showed maximal reporter activity, with the cAMP response element (CRE) essential for transcriptional activity. DEX caused inhibition in most constructs containing the CRE element whereas HC stimulated reporter activity in the 807 bp construct. Glucocorticoids inhibited the adrenergic stimulation of Dio2 at the transcriptional level in brown adipocytes, although DIO2 activity increased with HC, possibly due to stabilization of Dio2 activity and mRNA. The CRE and cEBP elements of the Dio2 promoter seem involved in the regulation by glucocorticoids. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Regulation of myosin light chain kinase during insulin-stimulated glucose uptake in 3T3-L1 adipocytes.

    Directory of Open Access Journals (Sweden)

    Shelly Woody

    Full Text Available Myosin II (MyoII is required for insulin-responsive glucose transporter 4 (GLUT4-mediated glucose uptake in 3T3-L1 adipocytes. Our previous studies have shown that insulin signaling stimulates phosphorylation of the regulatory light chain (RLC of MyoIIA via myosin light chain kinase (MLCK. The experiments described here delineate upstream regulators of MLCK during insulin-stimulated glucose uptake. Since 3T3-L1 adipocytes express two MyoII isoforms, we wanted to determine which isoform was required for insulin-stimulated glucose uptake. Using a siRNA approach, we demonstrate that a 60% decrease in MyoIIA protein expression resulted in a 40% inhibition of insulin-stimulated glucose uptake. We also show that insulin signaling stimulates the phosphorylation of MLCK. We further show that MLCK can be activated by calcium as well as signaling pathways. We demonstrate that adipocytes treated with the calcium chelating agent, 1,2-b (iso-aminophenoxy ethane-N,N,N',N'-tetra acetic acid, (BAPTA (in the presence of insulin impaired the insulin-induced phosphorylation of MLCK by 52% and the RLC of MyoIIA by 45% as well as impairing the recruitment of MyoIIA to the plasma membrane when compared to cells treated with insulin alone. We further show that the calcium ionophore, A23187 alone stimulated the phosphorylation of MLCK and the RLC associated with MyoIIA to the same extent as insulin. To identify signaling pathways that might regulate MLCK, we examined ERK and CaMKII. Inhibition of ERK2 impaired phosphorylation of MLCK and insulin-stimulated glucose uptake. In contrast, while inhibition of CaMKII did inhibit phosphorylation of the RLC associated with MyoIIA, inhibition of CAMKIIδ did not impair MLCK phosphorylation or translocation to the plasma membrane or glucose uptake. Collectively, our results are the first to delineate a role for calcium and ERK in the activation of MLCK and thus MyoIIA during insulin-stimulated glucose uptake in 3T3-L1 adipocytes.

  13. Adipocyte SIRT1 knockout promotes PPARγ activity, adipogenesis and insulin sensitivity in chronic-HFD and obesity.

    Science.gov (United States)

    Mayoral, Rafael; Osborn, Olivia; McNelis, Joanne; Johnson, Andrew M; Oh, Da Young; Izquierdo, Cristina Llorente; Chung, Heekyung; Li, Pingping; Traves, Paqui G; Bandyopadhyay, Gautam; Pessentheiner, Ariane R; Ofrecio, Jachelle M; Cook, Joshua R; Qiang, Li; Accili, Domenico; Olefsky, Jerrold M

    2015-05-01

    Adipose tissue is the primary site for lipid deposition that protects the organisms in cases of nutrient excess during obesogenic diets. The histone deacetylase Sirtuin 1 (SIRT1) inhibits adipocyte differentiation by targeting the transcription factor peroxisome proliferator activated-receptor gamma (PPARγ). To assess the specific role of SIRT1 in adipocytes, we generated Sirt1 adipocyte-specific knockout mice (ATKO) driven by aP2 promoter onto C57BL/6 background. Sirt1 (flx/flx) aP2Cre (+) (ATKO) and Sirt1 (flx/flx) aP2Cre (-) (WT) mice were fed high-fat diet for 5 weeks (short-term) or 15 weeks (chronic-term). Metabolic studies were combined with gene expression analysis and phosphorylation/acetylation patterns in adipose tissue. On standard chow, ATKO mice exhibit low-grade chronic inflammation in adipose tissue, along with glucose intolerance and insulin resistance compared with control fed mice. On short-term HFD, ATKO mice become more glucose intolerant, hyperinsulinemic, insulin resistant and display increased inflammation. During chronic HFD, WT mice developed a metabolic dysfunction, higher than ATKO mice, and thereby, knockout mice are more glucose tolerant, insulin sensitive and less inflamed relative to control mice. SIRT1 attenuates adipogenesis through PPARγ repressive acetylation and, in the ATKO mice adipocyte PPARγ was hyperacetylated. This high acetylation was associated with a decrease in Ser273-PPARγ phosphorylation. Dephosphorylated PPARγ is constitutively active and results in higher expression of genes associated with increased insulin sensitivity. Together, these data establish that SIRT1 downregulation in adipose tissue plays a previously unknown role in long-term inflammation resolution mediated by PPARγ activation. Therefore, in the context of obesity, the development of new therapeutics that activate PPARγ by targeting SIRT1 may provide novel approaches to the treatment of T2DM.

  14. Effect of germinated brown rice extracts on pancreatic lipase, adipogenesis and lipolysis in 3T3-L1 adipocytes.

    Science.gov (United States)

    Lim, See Meng; Goh, Yong Meng; Kuan, Wen Bin; Loh, Su Peng

    2014-11-03

    This study investigated anti-obesity effects of seven different solvent (n-hexane, toluene, dicholoromethane, ethyl acetate, absolute methanol, 80% methanol and deionized water) extracts of germinated brown rice (GBR) on pancreatic lipase activity, adipogenesis and lipolysis in 3T3-L1 adipocytes. GBR were extracted separately by employing different solvents with ultrasound-assisted. Pancreatic lipase activity was determined spectrophotometrically by measuring the hydrolysis of p-nitrophenyl butyrate (p-NPB) to p-nitrophenol at 405 nm. Adipogenesis and lipolysis were assayed in fully differentiated 3T3-L1 adipocytes by using Oil Red O staining and glycerol release measurement. GBR extract using hexane showed the highest inhibitory effect (13.58 ± 0.860%) at concentration of 200 μg/ml followed by hexane extract at 100 μg/ml (9.98 ± 1.048%) while ethyl acetate extract showed the lowest (2.62 ± 0.677%) at concentration of 200 μg/ml on pancreatic lipase activity. Water extract at 300 μg/ml showed 61.55 ± 3.824% of Oil Red O staining material (OROSM), a marker of adipogenesis. It significantly decrease (p < 0.05) lipid accumulation than control (OROSM = 100%), follow by ethyl acetate extract at 300 μg/ml (OROSM = 65.17 ± 3.131%). All the GBR extracts induced lipolysis with 1.22-1.83 fold of greater glycerol release than control. GBR extracts especially the least polar and intermediate polar solvent extracts exhibited inhibitory effect on pancreatic lipase, decrease fat accumulation by adipocyte differentiation inhibition, and stimulate lipolysis on adipocytes. Therefore, GBR could be furthered study and developed as a functional food in helping the treatment and/or prevention of obesity.

  15. Activation of peroxisome proliferator-activated receptor-α enhances fatty acid oxidation in human adipocytes

    International Nuclear Information System (INIS)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki; Kawada, Teruo

    2011-01-01

    Highlights: → PPARα activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. → PPARα activation also increased insulin-dependent glucose uptake in human adipocytes. → PPARα activation did not affect lipid accumulation in human adipocytes. → PPARα activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-α (PPARα) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPARα in adipocytes have been unclarified. We examined the functions of PPARα using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPARα by GW7647, a potent PPARα agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPARγ, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPARα activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPARγ is activated. On the other hand, PPARα activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPARα-dependent manner. Moreover, PPARα activation increased the production of CO 2 and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPARα stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPARα agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected effects of PPARα activation are very valuable for managing diabetic conditions accompanied by obesity, because

  16. Histone Deacetylase 1 (HDAC1) Negatively Regulates Thermogenic Program in Brown Adipocytes via Coordinated Regulation of Histone H3 Lysine 27 (H3K27) Deacetylation and Methylation.

    Science.gov (United States)

    Li, Fenfen; Wu, Rui; Cui, Xin; Zha, Lin; Yu, Liqing; Shi, Hang; Xue, Bingzhong

    2016-02-26

    Inhibiting class I histone deacetylases (HDACs) increases energy expenditure, reduces adiposity, and improves insulin sensitivity in obese mice. However, the precise mechanism is poorly understood. Here, we demonstrate that HDAC1 is a negative regulator of the brown adipocyte thermogenic program. The Hdac1 level is lower in mouse brown fat (BAT) than white fat, is suppressed in mouse BAT during cold exposure or β3-adrenergic stimulation, and is down-regulated during brown adipocyte differentiation. Remarkably, overexpressing Hdac1 profoundly blocks, whereas deleting Hdac1 significantly enhances, β-adrenergic activation-induced BAT-specific gene expression in brown adipocytes. β-Adrenergic activation in brown adipocytes results in a dissociation of HDAC1 from promoters of BAT-specific genes, including uncoupling protein 1 (Ucp1) and peroxisome proliferator-activated receptor γ co-activator 1α (Pgc1α), leading to increased acetylation of histone H3 lysine 27 (H3K27), an epigenetic mark of gene activation. This is followed by dissociation of the polycomb repressive complexes, including the H3K27 methyltransferase enhancer of zeste homologue (EZH2), suppressor of zeste 12 (SUZ12), and ring finger protein 2 (RNF2) from (and concomitant recruitment of H3K27 demethylase ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) to) Ucp1 and Pgc1α promoters, leading to decreased H3K27 trimethylation, a histone transcriptional repression mark. Thus, HDAC1 negatively regulates the brown adipocyte thermogenic program, and inhibiting Hdac1 promotes BAT-specific gene expression through a coordinated control of increased acetylation and decreased methylation of H3K27, thereby switching the transcriptional repressive state to the active state at the promoters of Ucp1 and Pgc1α. Targeting HDAC1 may be beneficial in prevention and treatment of obesity by enhancing BAT thermogenesis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Butein induction of HO-1 by p38 MAPK/Nrf2 pathway in adipocytes attenuates high-fat diet induced adipose hypertrophy in mice.

    Science.gov (United States)

    Wang, Zheng; Ka, Sun-O; Lee, Youngyi; Park, Byung-Hyun; Bae, Eun Ju

    2017-03-15

    Adipose tissue inflammation and oxidative stress are key components in the development of obesity and insulin resistance. Heme oxygenase (HO)-1 in adipocytes protects against obesity and adipose dysfunction. In this study, we report the identification of butein, a flavonoid chalcone, as a novel inducer of HO-1 expression in adipocytes in vitro and in vivo. Butein upregulated HO-1 mRNA and protein expression in 3T3-L1 adipocytes, accompanied by Kelch-Like ECH-Associated Protein (Keap) 1 degradation and increase in the nuclear level of nuclear factor erythroid 2-related factor 2 (Nrf2). Butein modulation of Keap1 and Nrf2 as well as HO-1 upregulation was reversed by pretreatment with p38 MAPK inhibitor SB203580, indicating the involvement of p38 MAPK in butein activation of Nrf2 in adipocytes. In addition, HO-1 activation by butein led to the inhibitions of reactive oxygen species and adipocyte differentiation, as evidenced by the fact that butein repression of reactive oxygen species and adipogenesis was reversed by pretreatment with HO-1 inhibitor SnPP. Induction of HO-1 expression by butein was also demonstrated in the adipose tissue of C57BL/6 mice fed a high-fat diet administered along with butein for three weeks, and correlated with the inhibitions of adiposity and adipose tissue inflammation, which were reversed by co-administration of SnPP. Altogether, our results demonstrate that butein activates the p38 MAPK/Nrf2/HO-1 pathway to act as a potent inhibitor of adipose hypertrophy and inflammation in a diet-induced obesity model and thus has potential for suppressing obesity-linked metabolic syndrome. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Ebf1-dependent control of the osteoblast and adipocyte lineages.

    Science.gov (United States)

    Hesslein, David G T; Fretz, Jackie A; Xi, Yougen; Nelson, Tracy; Zhou, Shoaming; Lorenzo, Joseph A; Schatz, David G; Horowitz, Mark C

    2009-04-01

    Ebf1 is a transcription factor essential for B cell fate specification and function and important for the development of olfactory sensory neurons. We show here that Ebf1 also plays an important role in regulating osteoblast and adipocyte development in vivo. Ebf1 mRNA and protein is expressed in MSCs, in OBs at most stages of differentiation, and in adipocytes. Tibiae and femora from Ebf1(-/-) mice had a striking increase in all bone formation parameters examined including the number of OBs, osteoid volume, and bone formation rate. Serum osteocalcin, a marker of bone formation, was significantly elevated in mutant mice. The numbers of osteoclasts in bone were normal in younger (4 week-old) Ebf1(-/-) mice but increased in older (12 week-old) Ebf1(-/-) mice. This correlated well with in vitro osteoclast development from bone marrow cells. In addition to the increased osteoblastogenesis, there was a dramatic increase in adipocyte numbers in the bone marrow of Ebf1(-/-) mice. Increased adiposity was also seen histologically in the liver but not in the spleen of these mice, and accompanied by decreased deposition of adipose to subcutaneous sites. Thus Ebf1-deficient mice appear to be a new model of lipodystrophy. Ebf1 is a rare example of a transcription factor that regulates both the osteoblast and adipocyte lineages similarly.

  19. Thermogenic adipocytes promote HDL turnover and reverse cholesterol transport.

    Science.gov (United States)

    Bartelt, Alexander; John, Clara; Schaltenberg, Nicola; Berbée, Jimmy F P; Worthmann, Anna; Cherradi, M Lisa; Schlein, Christian; Piepenburg, Julia; Boon, Mariëtte R; Rinninger, Franz; Heine, Markus; Toedter, Klaus; Niemeier, Andreas; Nilsson, Stefan K; Fischer, Markus; Wijers, Sander L; van Marken Lichtenbelt, Wouter; Scheja, Ludger; Rensen, Patrick C N; Heeren, Joerg

    2017-04-19

    Brown and beige adipocytes combust nutrients for thermogenesis and through their metabolic activity decrease pro-atherogenic remnant lipoproteins in hyperlipidemic mice. However, whether the activation of thermogenic adipocytes affects the metabolism and anti-atherogenic properties of high-density lipoproteins (HDL) is unknown. Here, we report a reduction in atherosclerosis in response to pharmacological stimulation of thermogenesis linked to increased HDL levels in APOE*3-Leiden.CETP mice. Both cold-induced and pharmacological thermogenic activation enhances HDL remodelling, which is associated with specific lipidomic changes in mouse and human HDL. Furthermore, thermogenic stimulation promotes HDL-cholesterol clearance and increases macrophage-to-faeces reverse cholesterol transport in mice. Mechanistically, we show that intravascular lipolysis by adipocyte lipoprotein lipase and hepatic uptake of HDL by scavenger receptor B-I are the driving forces of HDL-cholesterol disposal in liver. Our findings corroborate the notion that high metabolic activity of thermogenic adipocytes confers atheroprotective properties via increased systemic cholesterol flux through the HDL compartment.

  20. Regulation of adipocyte differentiation and function by polyunsaturated fatty acids

    DEFF Research Database (Denmark)

    Madsen, Lise; Petersen, Rasmus Koefoed; Kristiansen, Karsten

    2005-01-01

    factors currently implicated as key players in adipocyte differentiation and function, including peroxisome proliferator activated receptors (PPARs) (alpha, beta and gamma), sterol regulatory element binding proteins (SREBPs) and liver X receptors (LXRs). We review evidence that dietary n-3 PUFAs decrease...

  1. Divergent effects of selective peroxisome proliferator-activated receptor-gamma 2 ligands on adipocyte versus osteoblast differentiation.

    Science.gov (United States)

    Lecka-Czernik, Beata; Moerman, Elena J; Grant, David F; Lehmann, Jürgen M; Manolagas, Stavros C; Jilka, Robert L

    2002-06-01

    PPAR gamma is activated by diverse ligands and regulates the differentiation of many cell types. Based on evidence that activation of PPAR gamma 2 by rosiglitazone stimulates adipogenesis and inhibits osteoblastogenesis in U-33/gamma 2 cells, a model mesenchymal progenitor of adipocytes and osteoblasts, we postulated that the increase in marrow fat and the decrease in osteoblast number that occur during aging are due to increased PPAR gamma 2 activation. Here, we show that the naturally occurring PPAR gamma ligands 9,10-dihydroxyoctadecenoic acid, and 15-deoxy-Delta(12,14)-PGJ(2), also stimulate adipocytes and inhibit osteoblast differentiation of U-33/gamma 2 cells. Strikingly, 9,10-epoxyoctadecenoic acid and the thiazolidine acetamide ligand GW0072 [(+/-)-(2S,5S)-4-(4-(4-carboxyphenyl)butyl)-2-heptyl-4-oxo-5-thaizolidineN,N-dibenzyl-acetamide] prevent osteoblast differentiation, but do not stimulate adipogenesis, whereas 9-hydroxyoctadecadienoic acid stimulates adipogenesis but does not affect osteoblast differentiation. The divergent effects of PPAR gamma 2 ligands on osteoblast and adipocyte differentiation were confirmed in primary murine bone marrow cultures using rosiglitazone and GW0072. These findings indicate that the proadipogenic and antiosteoblastogenic effects of PPAR gamma 2 are mediated by distinct regulatory pathways that can be differentially modulated depending on the nature of the ligand, and they support the idea that increased fatty acid oxidation during aging may inhibit osteoblast differentiation. Moreover, there may be selective PPAR gamma 2 modulators that block the adverse effects of fatty acid oxidation products while retaining beneficial activities such as insulin sensitization.

  2. Effects of Wnt signaling on brown adipocyte differentiation and metabolism mediated by PGC-1alpha

    DEFF Research Database (Denmark)

    Kang, Sona; Bajnok, Laszlo; Longo, Kenneth A

    2005-01-01

    Activation of canonical Wnt signaling inhibits brown adipogenesis of cultured cells by impeding induction of PPARgamma and C/EBPalpha. Although enforced expression of these adipogenic transcription factors restores lipid accumulation and expression of FABP4 in Wnt-expressing cells, additional...... expression of PGC-1alpha is required for activation of uncoupling protein 1 (UCP1). Wnt10b blocks brown adipose tissue development and expression of UCP1 when expressed from the fatty acid binding protein 4 promoter, even when mice are administered a beta3-agonist. In differentiated brown adipocytes......, activation of Wnt signaling suppresses expression of UCP1 through repression of PGC-1alpha. Consistent with these in vitro observations, UCP1-Wnt10b transgenic mice, which express Wnt10b in interscapular tissue, lack functional brown adipose tissue. While interscapular tissue of UCP1-Wnt10b mice lacks...

  3. MDM2 facilitates adipocyte differentiation through CRTC-mediated activation of STAT3

    DEFF Research Database (Denmark)

    Hallenborg, P.; Siersbæk, M.; Barrio-Hernandez, I.

    2016-01-01

    on activation of the STAT family of transcription factors. Their activation was required for the cAMP-mediated induction of target genes. Interestingly, rather than influencing all cAMP-stimulated genes, inhibition of the kinases directly responsible for STAT activation, namely JAKs, or ablation of MDM2, each......The ubiquitin ligase MDM2 is best known for balancing the activity of the tumor suppressor p53. We have previously shown that MDM2 is vital for adipocyte conversion through controlling Cebpd expression in a p53-independent manner. Here, we show that the proadipogenic effect of MDM2 relies...... resulted in abolished induction of a subset of cAMP-stimulated genes, with Cebpd being among the most affected. Moreover, STATs were able to interact with the transcriptional cofactors CRTC2 and CRTC3, hitherto only reported to associate with the cAMP-responsive transcription factor CREB. Last...

  4. Distinct expression of muscle-specific microRNAs (myomirs) in brown adipocytes

    DEFF Research Database (Denmark)

    Walden, Tomas B; Timmons, James A; Keller, Pernille

    2009-01-01

    MicroRNAs, a novel class of post-transcriptional gene regulators, have been demonstrated to be involved in several cellular processes regulating the expression of protein-coding genes. Here we examine murine white and brown primary cell cultures for differential expression of mi...... regulated. However, expression of the miRNA miR-455 was enhanced during brown adipocyte differentiation, similarly to the expression pattern of the brown adipocyte differentiation marker UCP1. In conclusion, miRNAs are differentially expressed in white and brown adipocytes and may be important in defining......RNAs. The adipogenesis-related miRNA miR-143 was highly expressed in mature white adipocytes but was low in mature brown adipocytes. Three classical "myogenic" miRNAs miR-1, miR-133a and miR-206 were absent from white adipocytes but were specifically expressed both in brown pre- and mature adipocytes, reinforcing...

  5. Cell source, differentiation, functional stimulation, and potential application of human thermogenic adipocytes in vitro.

    Science.gov (United States)

    Chu, Dinh-Toi; Tao, Yang; Son, Le Hoang; Le, Duc-Hau

    2016-08-01

    Recent investigations have showed that the functional thermogenic adipocytes are present in both infants and adult humans. Accumulating evidence suggests that the coexistence of classical and inducible brown (brite) adipocytes in humans at adulthood and these adipocytes function to generate heat from energy resulting in reducing body fat and improving glucose metabolism. Human thermogenic adipocytes can be differentiated in vitro from stem cells, cell lines, or adipose stromal vascular fraction. Pre-activated human brite adipocytes in vitro can maintain their thermogenic function in normal or obese immunodeficient mice; therefore, they improve glucose homeostasis and reduce fat mass in obese animals. These key findings have opened a new door to use in vitro thermogenic adipocytes as a cell therapy to prevent obesity and related disorders. Thus, this paper intends to highlight our knowledge in aspects of in vitro human brite/brown adipocytes for the further studies.

  6. Extracellular Vesicles from Hypoxic Adipocytes and Obese Subjects Reduce Insulin‐Stimulated Glucose Uptake

    Science.gov (United States)

    Mleczko, Justyna; Ortega, Francisco J.; Falcon‐Perez, Juan Manuel; Wabitsch, Martin; Fernandez‐Real, Jose Manuel

    2018-01-01

    Scope We investigate the effects of extracellular vesicles (EVs) obtained from in vitro adipocyte cell models and from obese subjects on glucose transport and insulin responsiveness. Methods and results EVs are isolated from the culture supernatant of adipocytes cultured under normoxia, hypoxia (1% oxygen), or exposed to macrophage conditioned media (15% v/v). EVs are isolated from the plasma of lean individuals and subjects with obesity. Cultured adipocytes are incubated with EVs and activation of insulin signalling cascades and insulin‐stimulated glucose transport are measured. EVs released from hypoxic adipocytes impair insulin‐stimulated 2‐deoxyglucose uptake and reduce insulin mediated phosphorylation of AKT. Insulin‐mediated phosphorylation of extracellular regulated kinases (ERK1/2) is not affected. EVs from individuals with obesity decrease insulin stimulated 2‐deoxyglucose uptake in adipocytes (p = 0.0159). Conclusion EVs released by stressed adipocytes impair insulin action in neighboring adipocytes. PMID:29292863

  7. Distinctive effects of licarin A on lipolysis mediated by PKA and on formation of brown adipocytes from C3H10T1/2 mesenchymal stem cells.

    Science.gov (United States)

    Yoon, Dahyeon; Imran, Khan Mohammad; Kim, Yong-Sik

    2018-02-01

    Obesity increases with the positive energy imbalance and correlates with increased risks for metabolic diseases. Promotion of white adipose tissue beiging has received considerable attention due to possible usefulness for preventing obesity and the comorbidities. Licarin A (LA) is a compound derived from Mexican medicinal plant Aristolochia taliscana. Here, we report that LA stimulates the development of brown-like and beige-like adipocytes from C3H10T1/2 mesenchymal stem cells with phenotypic shifts to formation of smaller lipid droplets. LA also markedly induced the expression of proteins characteristic of brown-like adipocytes in C3H10T1/2 mesenchymal stem cells. LA induced uncoupling protein 1 (Ucp1) and expression of other thermogenic genes in C3H10T1/2 mesenchymal stem cells via a mechanism involving protein kinase A (PKA). LA treatment also inhibited expression of white-adipocyte-specific genes. Moreover, LA treatment promoted lipolysis via PKA mediated pathway. Our findings inaugurate a new role of LA as an inducer of brown-like adipocytes formation with lipolytic properties, which in future might be studied in vivo as a potential anti-obesity agent. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Cyanidin-3-rutinoside increases glucose uptake by activating the PI3K/Akt pathway in 3T3-L1 adipocytes.

    Science.gov (United States)

    Choi, Kyung Ha; Lee, Hyun Ah; Park, Mi Hwa; Han, Ji-Sook

    2017-09-01

    In this study, the effect of cyanidin-3-rutinoside (C3R) on glucose uptake by 3T3-L1 adipocytes was studied. C3R significantly increased glucose uptake, which was associated with enhanced plasma membrane glucose transporter type 4 (PM-GLUT4) expression in 3T3-L1 adipocytes. The potentiating effect of C3R on glucose uptake and PM-GLUT4 expression was related to enhanced phosphorylation of insulin receptor substrate 1 (IRS-1) and Akt, as well as augmented activation of phosphatidylinositol-3-kinase (PI3K) in the insulin signaling pathway. C3R induced glucose uptake was inhibited only by the PI3K inhibitor, but not by an AMPK inhibitor in 3T3-L1 adipocytes. Therefore, C3R likely up-regulates glucose uptake and PM-GLUT4 expression in 3T3-L1 adipocytes by activating the PI3K/Akt pathways. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Bisphenol-A impairs insulin action and up-regulates inflammatory pathways in human subcutaneous adipocytes and 3T3-L1 cells.

    Directory of Open Access Journals (Sweden)

    Rossella Valentino

    Full Text Available Current evidence indicates that chemical pollutants may interfere with the homeostatic control of nutrient metabolism, thereby contributing to the increased prevalence of metabolic disorders. Bisphenol-A (BPA is a lipophilic compound contained in plastic which is considered a candidate for impairing energy and glucose metabolism. We have investigated the impact of low doses of BPA on adipocyte metabolic functions. Human adipocytes derived from subcutaneous adipose tissue and differentiated 3T3-L1 cells were incubated with BPA, in order to evaluate the effect on glucose utilization, insulin sensitivity and cytokine secretion. Treatment with 1 nM BPA significantly inhibited insulin-stimulated glucose utilization, without grossly interfering with adipocyte differentiation. Accordingly, mRNA levels of the adipogenic markers PPARγ and GLUT4 were unchanged upon BPA exposure. BPA treatment also impaired insulin-activated receptor phosphorylation and signaling. Moreover, adipocyte incubation with BPA was accompanied by increased release of IL-6 and IFN-γ, as assessed by multiplex ELISA assays, and by activation of JNK, STAT3 and NFkB pathways. Treatment of the cells with the JNK inhibitor SP600125 almost fully reverted BPA effect on insulin signaling and glucose utilization. In conclusion, low doses of BPA interfere with inflammatory/insulin signaling pathways, leading to impairment of adipose cell function.

  10. Phillyrin, a natural lignan, attenuates tumor necrosis factor α-mediated insulin resistance and lipolytic acceleration in 3T3-L1 adipocytes.

    Science.gov (United States)

    Kong, Poren; Zhang, Linlin; Guo, Yuyu; Lu, Yingli; Lin, Dongping

    2014-07-01

    In obese adipose tissue, tumor necrosis factor-α secreted from macrophages plays an important role in the adipocyte dysfunctions, including insulin resistance, lipolytic acceleration, and changes of adipokines, which promote the development of obesity-related complications. Phillyrin, an active ingredient found in many medicinal plants and certain functional foods, elicits anti-obesity and anti-inflammatory properties in vivo. The aim of the current study was to investigate the role of phillyrin in preventing tumor necrosis factor α-induced insulin resistance or lipolytic acceleration in 3T3-L1 adipocytes. Our results showed that phillyrin partially restored insulin-stimulated 2-DOG uptake, which was reduced by tumor necrosis factor-α, with concomitant restoration in serine phosphorylation of insulin receptor substrate-1 and insulin-stimulated Glut4 translocation to plasma membrane. Phillyrin also dose-dependently prevented tumor necrosis factor α-stimulated adipocyte lipolysis with preserved downregulation of perilipin. The mitogen-activated protein kinases and I kappaB kinase activation was promoted in tumor necrosis factor α-stimulated adipocytes, but pretreatment with 40 µM phillyrin inhibited the phosphorylation of extracellular signal-regulated kinases1/2, stress-activated protein kinase/Jun N-terminal kinase and I kappaB kinase (pobese adipose tissue. Georg Thieme Verlag KG Stuttgart · New York.

  11. Salt modulates the stability and lipid binding affinity of the adipocyte lipid-binding proteins

    Science.gov (United States)

    Schoeffler, Allyn J.; Ruiz, Carmen R.; Joubert, Allison M.; Yang, Xuemei; LiCata, Vince J.

    2003-01-01

    Adipocyte lipid-binding protein (ALBP or aP2) is an intracellular fatty acid-binding protein that is found in adipocytes and macrophages and binds a large variety of intracellular lipids with high affinity. Although intracellular lipids are frequently charged, biochemical studies of lipid-binding proteins and their interactions often focus most heavily on the hydrophobic aspects of these proteins and their interactions. In this study, we have characterized the effects of KCl on the stability and lipid binding properties of ALBP. We find that added salt dramatically stabilizes ALBP, increasing its Delta G of unfolding by 3-5 kcal/mol. At 37 degrees C salt can more than double the stability of the protein. At the same time, salt inhibits the binding of the fluorescent lipid 1-anilinonaphthalene-8-sulfonate (ANS) to the protein and induces direct displacement of the lipid from the protein. Thermodynamic linkage analysis of the salt inhibition of ANS binding shows a nearly 1:1 reciprocal linkage: i.e. one ion is released from ALBP when ANS binds, and vice versa. Kinetic experiments show that salt reduces the rate of association between ANS and ALBP while simultaneously increasing the dissociation rate of ANS from the protein. We depict and discuss the thermodynamic linkages among stability, lipid binding, and salt effects for ALBP, including the use of these linkages to calculate the affinity of ANS for the denatured state of ALBP and its dependence on salt concentration. We also discuss the potential molecular origins and potential intracellular consequences of the demonstrated salt linkages to stability and lipid binding in ALBP.

  12. Uptake of oleate by isolated rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut

    International Nuclear Information System (INIS)

    Schwieterman, W.; Sorrentino, D.; Potter, B.J.; Rand, J.; Kiang, C.L.; Stump, D.; Berk, P.D.

    1988-01-01

    A portion of the hepatocellular uptake of nonesterified long-chain fatty acids is mediated by a specific 40-kDa plasma membrane fatty acid binding protein, which has also been isolated from the gut. To investigate whether a similar transport process exists in other tissues with high transmembrane fatty acid fluxes, initial rates (V/sub O/) of [ 3 H]-oleate uptake into isolated rat adipocytes were studied as a function of the concentration of unbound [ 3 H]oleate in the medium. V/sub O/ reached a maximum as the concentration of unbound oleate was increased and was significantly inhibited both by phloretin and by prior incubation of the cells with Pronase. A rabbit antibody to the rat liver plasma membrane fatty acid binding protein inhibited adipocyte fatty acid uptake by up to 63% in dose-dependent fashion. Inhibition was noncompetitive; at an immunoglobulin concentration of 250 μg/ml V/sub max/ was reduced from 2480 /plus minus/ 160 to 1870 /plus minus/ 80 pmol/min per 5 /times/ 10 4 adipocytes, with no change in K/sub m/. A basic kDa adipocyte plasma membrane fatty acid binding protein, isolated from crude adipocyte plasma membrane fractions, reacted strongly in both agar gel diffusion and electrophoretic blots with the antibody raised against the corresponding hepatic plasma membrane protein. These data indicate that the uptake of oleate by rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut

  13. Effect of TNF-Alpha on Caveolin-1 Expression and Insulin Signaling During Adipocyte Differentiation and in Mature Adipocytes

    Directory of Open Access Journals (Sweden)

    Sara Palacios-Ortega

    2015-07-01

    Full Text Available Background/Aims: Tumor necrosis factor-α (TNF-α-mediated chronic low-grade inflammation of adipose tissue is associated with obesity and insulin resistance. Caveolin-1 (Cav-1 is the central component of adipocyte caveolae and has an essential role in the regulation of insulin signaling. The effects of TNF-α on Cav-1 expression and insulin signaling during adipocyte differentiation and in mature adipocytes were studied. Methods: 3T3-L1 cells were differentiated (21 days in the presence TNF-α (10 ng/mL and mature adipocytes were also treated with TNF-α for 48 hours. Cav-1 and insulin receptor (IR gene methylation were determined as well as Cav-1, IR, PKB/AKT-2 and Glut-4 expression and activation by real time RT-PCR and western blot. Baseline and insulin-induced glucose uptake was measured by the 2-[C14]-deoxyglucose uptake assay. Results: TNF-α slowed down the differentiation program, hindering the expression of some insulin signaling intermediates without fully eliminating insulin-mediated glucose uptake. In mature adipocytes, TNF-α did not compromise lipid-storage capacity, but downregulated the expression of the insulin signaling intermediates, totally blocking insulin-mediated glucose uptake. Insulin sensitivity correlated with the level of activated phospho-Cav-1 in both situations, strongly suggesting the direct contribution of Cav-1 to the maintenance of this physiological response. Conclusion: Cav-1 activation by phosphorylation seems to be essential for the maintenance of an active and insulin-sensitive glucose uptake.

  14. Analysis of the enhanced oral bioavailability of fenofibrate lipid formulations in fasted humans using an in vitro-in silico-in vivo approach.

    Science.gov (United States)

    Fei, Yang; Kostewicz, Edmund S; Sheu, Ming-Thau; Dressman, Jennifer B

    2013-11-01

    Lipid-based formulations have established a significant role in the formulation of poorly soluble drugs for oral administration. In order to better understand their potential advantages over solid oral dosage forms, we studied the solubility and dissolution/precipitation characteristics of three self-microemulsifying drug delivery system (SMEDDS) formulations and one suspension of micronized fenofibrate in lipid excipients, for which pharmacokinetic studies had already been reported in the open literature. The in vitro dispersion/dissolution studies were carried out in biorelevant media using USP II apparatus. These were followed up by in silico simulations using STELLA® software, in which not only dispersion/dissolution, but also the precipitation and re-dissolution of fenofibrate was taken into account. While unformulated drug exhibited poor solubility (0.22 μg/mL in FaSSGF and 4.31 μg/mL in FaSSIF-V2(PO4)) and dissolved less than 2% in dissolution tests, the solubility of fenofibrate in the presence of the lipid excipients increased dramatically (e.g., to 65.44 μg/mL in the presence of the Myritol 318/TPGS/Tween 80 SMEDDS) and there was an attendant increase in the dissolution (over 80% from capsules containing the Myritol 318/TPGS/Tween 80 SMEDDS and about 20% from the dispersion of fenofibrate in lipid excipients). For the four lipid-based fenofibrate formulations studied, combining in vitro data in biorelevant media with in silico simulation resulted in accurate prediction of the in vivo human plasma profiles. The point estimates of C(max) and AUC ratio calculated from the in silico and in vivo plasma profiles fell within the 0.8-1.25 range for the SMEDDS solution and capsule formulations, suggesting an accurate simulation of the in vivo profiles. This similarity was confirmed by calculation of the respective f2 factors. Sensitivity analysis of the simulation profiles revealed that the SMEDDS formulations had virtually removed any dependency of absorption

  15. Melatonin alleviates inflammasome-induced pyroptosis through inhibiting NF-κB/GSDMD signal in mice adipose tissue.

    Science.gov (United States)

    Liu, Zhenjiang; Gan, Lu; Xu, Yatao; Luo, Dan; Ren, Qian; Wu, Song; Sun, Chao

    2017-08-01

    Pyroptosis is a proinflammatory form of cell death that is associated with pathogenesis of many chronic inflammatory diseases. Melatonin is substantially reported to possess anti-inflammatory properties by inhibiting inflammasome activation. However, the effects of melatonin on inflammasome-induced pyroptosis in adipocytes remain elusive. Here, we demonstrated that melatonin alleviated lipopolysaccharides (LPS)-induced inflammation and NLRP3 inflammasome formation in mice adipose tissue. The NLRP3 inflammasome-mediated pyroptosis was also inhibited by melatonin in adipocytes. Further analysis revealed that gasdermin D (GSDMD), the key executioner of pyroptosis, was the target for melatonin inhibition of adipocyte pyroptosis. Importantly, we determined that nuclear factor κB (NF-κB) signal was required for the GSDMD-mediated pyroptosis in adipocytes. We also confirmed that melatonin alleviated adipocyte pyroptosis by transcriptional suppression of GSDMD. Moreover, GSDMD physically interacted with interferon regulatory factor 7 (IRF7) and subsequently formed a complex to promote adipocyte pyroptosis. Melatonin also attenuated NLRP3 inflammasome activation and pyroptosis, which was induced by LPS or obesity. In summary, our results demonstrate that melatonin alleviates inflammasome-induced pyroptosis by blocking NF-κB/GSDMD signal in mice adipose tissue. Our data reveal a novel function of melatonin on adipocyte pyroptosis, suggesting a new potential therapy for melatonin to prevent and treat obesity caused systemic inflammatory response. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Effects of C-reactive protein on adipokines genes expression in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Yuan, Guoyue; Jia, Jue; Di, Liangliang; Zhou, Libin; Dong, Sijing; Ye, Jingjing; Wang, Dong; Yang, Ling; Wang, Jifang; Li, Lianxi; Yang, Ying; Mao, Chaoming; Chen, Mingdao

    2012-01-01

    Highlights: ► CRP increases TNF-α and IL-6 genes expression in matured 3T3-L1 adipocytes. ► CRP suppresses adiponectin, leptin and PPAR-γ mRNA levels in matured 3T3-L1 cells. ► Wortmannin reverses effects of CRP on adiponectin, TNF-α and leptin mRNA levels. ► CRP may regulate IR, obesity and metabolic syndrome by this mechanism. -- Abstract: Adipose tissue is now recognized to be an important endocrine organ, secreting a variety of adipokines that are involved in the regulation of energy metabolism, insulin resistance and metabolic syndrome. C-reactive protein (CRP) is considered as one of the most sensitive markers of inflammation. A number of studies have shown that elevation of CRP concentrations is an independent predictive parameter of type 2 diabetes mellitus, which is also strongly associated with various components of the metabolic syndrome. The aim of the present study is to investigate the effects of CRP on adipokines genes expression in 3T3-L1 adipocytes. Quantitative real-time PCR analysis revealed that CRP inhibited adiponectin, leptin and peroxisome proliferator-activated receptor-gamma (PPAR-γ) genes expression and raised tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA levels in matured 3T3-L1 adipocytes in a dose and time-dependent manner. Pharmacological inhibition of phosphatidylinositol (PI)-3 kinase by wortmannin partially reversed the effects of CRP on adiponectin, TNF-α and leptin genes expression. These results collectively suggest that CRP regulates adiponectin, TNF-α, leptin, IL-6 and PPAR-γ genes expression, and that might represent a mechanism by which CRP regulates insulin resistance, obesity and metabolic syndrome.

  17. Effects of C-reactive protein on adipokines genes expression in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Guoyue, E-mail: yuanguoyue@hotmail.com [Department of Endocrinology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001 (China); Jia, Jue; Di, Liangliang [Department of Endocrinology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001 (China); Zhou, Libin [Ruijin Hospital, Center of Molecular Medicine, Shanghai Institute of Endocrine and Metabolic Diseases, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University Medical School, 197, Ruijin Road II, Shanghai 200025 (China); Dong, Sijing; Ye, Jingjing; Wang, Dong; Yang, Ling; Wang, Jifang [Department of Endocrinology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001 (China); Li, Lianxi [Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, 600, Yishan Road, Shanghai 200233 (China); Yang, Ying [Ruijin Hospital, Center of Molecular Medicine, Shanghai Institute of Endocrine and Metabolic Diseases, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University Medical School, 197, Ruijin Road II, Shanghai 200025 (China); Mao, Chaoming [Department of Endocrinology, The Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu 212001 (China); Chen, Mingdao, E-mail: mingdaochensh@yahoo.com [Ruijin Hospital, Center of Molecular Medicine, Shanghai Institute of Endocrine and Metabolic Diseases, State Key Laboratory of Medical Genomics, Shanghai Jiaotong University Medical School, 197, Ruijin Road II, Shanghai 200025 (China)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer CRP increases TNF-{alpha} and IL-6 genes expression in matured 3T3-L1 adipocytes. Black-Right-Pointing-Pointer CRP suppresses adiponectin, leptin and PPAR-{gamma} mRNA levels in matured 3T3-L1 cells. Black-Right-Pointing-Pointer Wortmannin reverses effects of CRP on adiponectin, TNF-{alpha} and leptin mRNA levels. Black-Right-Pointing-Pointer CRP may regulate IR, obesity and metabolic syndrome by this mechanism. -- Abstract: Adipose tissue is now recognized to be an important endocrine organ, secreting a variety of adipokines that are involved in the regulation of energy metabolism, insulin resistance and metabolic syndrome. C-reactive protein (CRP) is considered as one of the most sensitive markers of inflammation. A number of studies have shown that elevation of CRP concentrations is an independent predictive parameter of type 2 diabetes mellitus, which is also strongly associated with various components of the metabolic syndrome. The aim of the present study is to investigate the effects of CRP on adipokines genes expression in 3T3-L1 adipocytes. Quantitative real-time PCR analysis revealed that CRP inhibited adiponectin, leptin and peroxisome proliferator-activated receptor-gamma (PPAR-{gamma}) genes expression and raised tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-6 (IL-6) mRNA levels in matured 3T3-L1 adipocytes in a dose and time-dependent manner. Pharmacological inhibition of phosphatidylinositol (PI)-3 kinase by wortmannin partially reversed the effects of CRP on adiponectin, TNF-{alpha} and leptin genes expression. These results collectively suggest that CRP regulates adiponectin, TNF-{alpha}, leptin, IL-6 and PPAR-{gamma} genes expression, and that might represent a mechanism by which CRP regulates insulin resistance, obesity and metabolic syndrome.

  18. Relationship of Adipocyte Size with Adiposity and Metabolic Risk Factors in Asian Indians

    Science.gov (United States)

    Meena, Ved Prakash; Seenu, V.; Sharma, M. C.; Mallick, Saumya Ranjan; Bhalla, Ashu Seith; Gupta, Nandita; Mohan, Anant; Guleria, Randeep; Pandey, Ravindra M.; Luthra, Kalpana; Vikram, Naval K.

    2014-01-01

    Background Enlargement of adipocyte is associated with their dysfunction and alterations in metabolic functions. Objectives We evaluated the association of adipocyte size of subcutaneous and omental adipose tissue with body composition and cardiovascular risk factors in Asian Indians. Methodology Eighty (40 males and 40 females) non-diabetic adult subjects undergoing elective abdominal surgery were included. Pre-surgery evaluation included anthropometric measurements, % body fat by bioimpedance, abdominal fat area at L2–3 level (computed tomography) and biochemical investigations (fasting blood glucose and insulin, lipids and hsCRP). During surgery, about 5 grams each of omental and subcutaneous adipose tissue was obtained for adipocyte size determination. Results Females had higher BMI, % body fat, skinfold thickness, total and subcutaneous abdominal fat area as compared to males. Overweight was present in 42.5% and 67.5%, and abdominal obesity in 5% and 52.5% males and females, respectively. Subcutaneous adipocyte size was significantly higher than omental adipocyte size. Omental adipocyte size correlated more strongly than subcutaneous adipocyte size with measures of adiposity (BMI, waist circumference, %BF), total and subcutaneous abdominal fat area and biochemical measures (fasting glucose, total cholesterol, triglycerides and HOMA-IR), the correlations being stronger in females. The correlation of adipocyte size with metabolic parameters was attenuated after adjusting for measures of adiposity. Conclusion Omental adipocyte size, though smaller than the subcutaneous adipocyte size, was more closely related to measures of adiposity and metabolic parameters. However, the relationship was not independent of measures of adiposity. PMID:25251402

  19. Relationship of adipocyte size with adiposity and metabolic risk factors in Asian Indians.

    Directory of Open Access Journals (Sweden)

    Ved Prakash Meena

    Full Text Available Enlargement of adipocyte is associated with their dysfunction and alterations in metabolic functions.We evaluated the association of adipocyte size of subcutaneous and omental adipose tissue with body composition and cardiovascular risk factors in Asian Indians.Eighty (40 males and 40 females non-diabetic adult subjects undergoing elective abdominal surgery were included. Pre-surgery evaluation included anthropometric measurements, % body fat by bioimpedance, abdominal fat area at L2-3 level (computed tomography and biochemical investigations (fasting blood glucose and insulin, lipids and hsCRP. During surgery, about 5 grams each of omental and subcutaneous adipose tissue was obtained for adipocyte size determination.Females had higher BMI, % body fat, skinfold thickness, total and subcutaneous abdominal fat area as compared to males. Overweight was present in 42.5% and 67.5%, and abdominal obesity in 5% and 52.5% males and females, respectively. Subcutaneous adipocyte size was significantly higher than omental adipocyte size. Omental adipocyte size correlated more strongly than subcutaneous adipocyte size with measures of adiposity (BMI, waist circumference, %BF, total and subcutaneous abdominal fat area and biochemical measures (fasting glucose, total cholesterol, triglycerides and HOMA-IR, the correlations being stronger in females. The correlation of adipocyte size with metabolic parameters was attenuated after adjusting for measures of adiposity.Omental adipocyte size, though smaller than the subcutaneous adipocyte size, was more closely related to measures of adiposity and metabolic parameters. However, the relationship was not independent of measures of adiposity.

  20. Clk/STY (cdc2-like kinase 1 and Akt regulate alternative splicing and adipogenesis in 3T3-L1 pre-adipocytes.

    Directory of Open Access Journals (Sweden)

    Pengfei Li

    Full Text Available The development of adipocytes from their progenitor cells requires the action of growth factors signaling to transcription factors to induce the expression of adipogenic proteins leading to the accumulation of lipid droplets, induction of glucose transport, and secretion of adipokines signaling metabolic events throughout the body. Murine 3T3-L1 pre-adipocytes sequentially express all the proteins necessary to become mature adipocytes throughout an 8-10 day process initiated by a cocktail of hormones. We examined the role of Clk/STY or Clk1, a cdc2-like kinase, in adipogenesis since it is known to be regulated by Akt, a pivotal kinase in development. Inhibition of Clk1 by a specific inhibitor, TG003, blocked alternative splicing of PKCβII and expression of PPARγ1 and PPARγ2. SiRNA depletion of Clk1 resulted in early expression of PKCβII and sustained PKCβI expression. Since Clk1 is a preferred Akt substrate, required for phosphorylation of splicing factors, mutation of Clk1 Akt phosphorylation sites was undertaken. Akt sites on Clk1 are in the serine/arginine-rich domain and not the kinase domain. Mutation of single and multiple sites resulted in dysregulation of PKCβII, PKCβI, and PPARγ1&2 expression. Additionally, adipogenesis was blocked as assessed by Oil Red O staining, adiponectin, and Glut1 and 4 expression. Immunofluorescence microscopy revealed that Clk1 triple mutant cDNA, transfected into pre-adipocytes, resulted in excluding SRp40 (SFSR6 from co-localizing to the nucleus with PFS, a perispeckle specific protein. This study demonstrates the role of Akt and Clk1 kinases in the early differentiation of 3T3-L1 cells to adipocytes.

  1. Clk/STY (cdc2-Like Kinase 1) and Akt Regulate Alternative Splicing and Adipogenesis in 3T3-L1 Pre-Adipocytes

    Science.gov (United States)

    Li, Pengfei; Carter, Gay; Romero, Jacqueline; Gower, Kathryn M.; Watson, James; Patel, Niketa A.; Cooper, Denise R.

    2013-01-01

    The development of adipocytes from their progenitor cells requires the action of growth factors signaling to transcription factors to induce the expression of adipogenic proteins leading to the accumulation of lipid droplets, induction of glucose transport, and secretion of adipokines signaling metabolic events throughout the body. Murine 3T3-L1 pre-adipocytes sequentially express all the proteins necessary to become mature adipocytes throughout an 8–10 day process initiated by a cocktail of hormones. We examined the role of Clk/STY or Clk1, a cdc2-like kinase, in adipogenesis since it is known to be regulated by Akt, a pivotal kinase in development. Inhibition of Clk1 by a specific inhibitor, TG003, blocked alternative splicing of PKCβII and expression of PPARγ1 and PPARγ2. SiRNA depletion of Clk1 resulted in early expression of PKCβII and sustained PKCβI expression. Since Clk1 is a preferred Akt substrate, required for phosphorylation of splicing factors, mutation of Clk1 Akt phosphorylation sites was undertaken. Akt sites on Clk1 are in the serine/arginine-rich domain and not the kinase domain. Mutation of single and multiple sites resulted in dysregulation of PKCβII, PKCβI, and PPARγ1&2 expression. Additionally, adipogenesis was blocked as assessed by Oil Red O staining, adiponectin, and Glut1 and 4 expression. Immunofluorescence microscopy revealed that Clk1 triple mutant cDNA, transfected into pre-adipocytes, resulted in excluding SRp40 (SFSR6) from co-localizing to the nucleus with PFS, a perispeckle specific protein. This study demonstrates the role of Akt and Clk1 kinases in the early differentiation of 3T3-L1 cells to adipocytes. PMID:23308182

  2. Distinct Regulatory Mechanisms Govern Embryonic versus Adult Adipocyte Maturation

    Science.gov (United States)

    Wang, Qiong A.; Tao, Caroline; Jiang, Lei; Shao, Mengle; Ye, Risheng; Zhu, Yi; Gordillo, Ruth; Ali, Aktar; Lian, Yun; Holland, William L.; Gupta, Rana K.; Scherer, Philipp E.

    2015-01-01

    Pathological expansion of adipose tissue contributes to the metabolic syndrome. Distinct depots develop at various times under different physiological conditions. The transcriptional cascade mediating adipogenesis is established in vitro, and centers around a core program involving PPARγ and C/EBPα. We developed an inducible, adipocyte-specific knockout system to probe the requirement of key adipogenic transcription factors at various stages of adipogenesis in vivo. C/EBPα is essential for all white adipogenic conditions in the adult stage, such as adipose tissue regeneration, adipogenesis in muscle and unhealthy expansion of white adipose tissue during high fat feeding or due to leptin deficiency. Surprisingly, terminal embryonic adipogenesis is fully C/EBPα independent, does depend however on PPARγ; cold-induced beige adipogenesis is also C/EBPα independent. Moreover, C/EBPα is not vital for adipocyte survival in the adult stage. We reveal a surprising diversity of transcriptional signals required at different stages of adipogenesis in vivo. PMID:26280538

  3. Adipose tissue remodeling in lipedema: adipocyte death and concurrent regeneration.

    Science.gov (United States)

    Suga, Hirotaka; Araki, Jun; Aoi, Noriyuki; Kato, Harunosuke; Higashino, Takuya; Yoshimura, Kotaro

    2009-12-01

    Lipedema is a disease with unknown etiology presenting as bilateral and symmetric enlargement of the lower extremities due to subcutaneous deposition of the adipose tissue. Here we describe the histopathological features of the lipedema tissue and nonaffected adipose tissue obtained from a typical patient with severe lipedema. Immunohistochemical analyses indicated degenerative and regenerative changes of the lipedema tissue, characterized by crown-like structures (necrotizing adipocytes surrounded by infiltrating CD68+ macrophages; a feature commonly seen in obese adipose tissue) and proliferation of adipose-derived stem/progenitor/stromal cells (Ki67+CD34+ cells), respectively. These findings suggested increased adipogenesis in the lipedema tissue, which may further lead to hypoxia similar to that seen in obesity, resulting in adipocyte necrosis and macrophage recruitment. The confinement to the lower extremities and the difference from systemic obesity warrants further elucidation in future studies.

  4. The Genetics of Brown Adipocyte Induction in White Fat Depots

    Directory of Open Access Journals (Sweden)

    Leslie P. Kozak

    2011-10-01

    Full Text Available Evidence that adult humans have functional brown adipose tissue has stirred interest in the possibility that the impressive effectiveness of induction of brown adipocytes to reduce obesity in mice may be translated to the human condition. A major focus recently on the identification of signaling and transcription factor that stimulate the induction of brown adipocytes has come from transgenic and gene KO models. However, these models have created a very complex picture of the regulatory mechanisms for brown fat induction. In this review insights into the critical regulatory pathways involved in brown adipocyte induction in the retroperitoneal fat depot of mice are described from quantitative trait locus analysis of allelic variability determining Ucp1 levels and brown adipocyte induction in A/J vs B6 mice. The key observation is that recombinant genotypes, found in recombinant inbred stains and backcross and intercross progeny , show transgressive variation for Ucp1 mRNA levels. These genetic crosses also show that the levels of Ucp1 mRNA are determined by interactions that control the levels of PPARα, PGC-1α and type 2 deiodinase and that each factor is controlled by a subset of QTLs that also control Ucp1expression. These results indicate that induction of Ucp1 in the retroperitoneal fat depot involves synergy between signaling and transcription factors that vary depending upon the environmental conditions. Inherent in this model is the idea that there is a high level of redundancy that can involve any factor with the potential to influence expression of the core factors, PPARα, PGC-1a and DIO2.

  5. Targeting the Adipocyte Tumor Cell Interaction in Prostate Cancer Treatment

    Science.gov (United States)

    2015-10-01

    performed in task 4.1. Task 7. 3D Organotypic cultures to study the adipocyte-PCa cell interaction in vitro (Months 30-36; Diaz-Meco & Moscat). This...Targeting Metabolic Reprograming in Cancer” Centro Nacional de Biotecnologia, Madrid, Spain, 2015. Speaker (Moscat) “Cell Death and Survival Networks...PCa, we profited from a recently devel- oped technology for creating 3D prostate organoid cultures (Gao et al., 2014; Karthaus et al., 2014). Murine

  6. Regulation of glycolysis in brown adipocytes by HIF-1α

    DEFF Research Database (Denmark)

    Basse, Astrid Linde; Isidor, Marie Sophie; Winther, Sally

    2017-01-01

    Brown adipose tissue takes up large amounts of glucose during cold exposure in mice and humans. Here we report an induction of glucose transporter 1 expression and increased expression of several glycolytic enzymes in brown adipose tissue from cold-exposed mice. Accordingly, these genes were also...... with glucose as the only exogenously added fuel. These data suggest that HIF-1α-dependent regulation of glycolysis is necessary for maximum glucose metabolism in brown adipocytes....

  7. Farnesol Has an Anti-obesity Effect in High-Fat Diet-Induced Obese Mice and Induces the Development of Beige Adipocytes in Human Adipose Tissue Derived-Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Hye-Lin Kim

    2017-09-01

    Full Text Available Brown adipocytes dissipate energy as heat and hence have an important therapeutic capacity for obesity. Development of brown-like adipocytes (also called beige is also another attractive target for obesity treatment. Here, we investigated the effect of farnesol, an isoprenoid, on adipogenesis in adipocytes and on the browning of white adipose tissue (WAT as well as on the weight gain of high-fat diet (HFD-induced obese mice. Farnesol inhibited adipogenesis and the related key regulators including peroxisome proliferator-activated receptor γ (PPARγ and CCAAT/enhancer binding protein α through the up-regulation of AMP-activated protein kinase in 3T3-L1 murine adipocytes and human adipose tissue-derived mesenchymal stem cells (hAMSCs. Farnesol markedly increased the expression of uncoupling protein 1 and PPARγ coactivator 1 α in differentiated hAMSCs. In addition, farnesol limited the weight gain in HFD obese mice and induced the development of beige adipocytes in both inguinal and epididymal WAT. These results suggest that farnesol could be a potential therapeutic agent for obesity treatment.

  8. Swift Quantification of Fenofibrate and Tiemonium methylsulfate Active Ingredients in Solid Drugs Using Particle Induced X-Ray Emission

    International Nuclear Information System (INIS)

    Bejjani, A.; Nsouli, B.; Zahraman, K.; Assi, S.; Younes, Gh.; Yazbi, F.

    2011-01-01

    The quantification of active ingredients (AI) in drugs is a crucial and important step in the drug quality control process. This is usually performed by using wet chemical techniques like LC-MS, UV spectrophotometry and other appropriate organic analytical methods. However, if the active ingredient contains specific heteroatoms (F, S, Cl), elemental IBA like PIXE and PIGE techniques, using small tandem accelerator of 1-2 MV, can be explored for molecular quantification. IBA techniques permit the analysis of the sample under solid form, without any laborious sample preparations. In this work, we demonstrate the ability of the Thick Target PIXE technique for rapid and accurate quantification of both low and high concentrations of active ingredients in different commercial drugs. Fenofibrate, a chlorinated active ingredient, is present in high amounts in two different commercial drugs, its quantification was done using the relative approach to an external standard. On the other hand, Tiemonium methylsulfate which exists in relatively low amount in commercial drugs, its quantification was done using GUPIX simulation code (absolute quantification). The experimental aspects related to the quantification validity (use of external standards, absolute quantification, matrix effect,...) are presented and discussed. (author)

  9. Reversal of dexamethasone induced insulin resistance in 3T3L1 adipocytes by 3β-taraxerol of Mangifera indica.

    Science.gov (United States)

    Sangeetha, K N; Shilpa, K; Jyothi Kumari, P; Lakshmi, B S

    2013-02-15

    The present study investigates the efficacy of Mangifera indica ethyl acetate extract (MIEE) and its bioactive compound, 3β-taraxerol in the reversal of dexamethasone (DEX) induced insulin resistance in 3T3L1 adipocytes. MIEE and 3β-taraxerol were evaluated for their ability to restore impaired glucose uptake and, expression of molecular markers in the insulin signaling pathway induced by DEX in 3T3L1 adipocytes using 2-deoxy-D-[1-(3)H] glucose uptake assay and ELISA. An insulin resistant model has been developed using a glucocorticoid, DEX on 3T3L1 adipocytes. Insulin resistant condition was observed at 24h of DEX induction wherein a maximum degree of resistance of about 50% was measured based on inhibition of glucose uptake, which was confirmed using cytotoxicity analysis. The developed model of insulin resistance was studied in comparison to positive control rosiglitazone. DEX induced inhibition of glucose uptake and the expression of insulin signaling markers GLUT4 and PI3K were found to be restored by 3β-taraxerol and MIEE, thus delineating its mechanism of action in the reversal of insulin resistance. 3β-Taraxerol effectively restored DEX induced desensitization via restoration of PI3K and GLUT4 expression. To conclude, since 3β-taraxerol exhibits significant effect in reversing insulin resistance it can be further investigated as an insulin resistance reversal agent. Copyright © 2012 Elsevier GmbH. All rights reserved.

  10. Differential expression of sirtuin 2 and adipocyte maturation restriction: an adaptation process during hypoxia in fish

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    Padmini Ekambaram

    2017-09-01

    b; Padmini and Tharani, 2015. In this context, fish adipocytes of both conditions were subjected to in vitro hypoxia for 1 h (in the pre/trigassed incubator with the supply of 1% O2; 94% N2; 5% CO2 and were analysed for the expression of adipokines, adipogenic transcription factors and anti-adipogenic markers in fish adipocytes. Elevation of asymmetric dimethylarginine (ADMA, TNFα and leptin along with decreased adiponectin, adipogenic transcription factors and altering sirtuins were observed in test adipocytes and in control adipocytes on in vitro hypoxia. This suggests that adipocytes may follow internal caloric restriction as portrayed from cytomorphological/ultrastructural analysis, limiting adipocyte maturation process, one of the adaptive mechanisms triggered by adipocyte of fish surviving in Ennore estuary. Prolonged exposure to hypoxia (test on in vitro hypoxia for 1 h showed a drastic alteration in these components leading to both structural and biological fluctuation when compared to limited hypoxic condition (field-hypoxic and control on in vitro hypoxia. Our study concludes that hypoxia may serve as the chief molecular cue in eliciting adipocyte maturation restriction though metabolic reprogramming and it also shows the significance of adipocyte maturation restriction in imparting survival mechanism.

  11. Anti-adipogenic effects of extracts of Ficus deltoidea var. deltoidea and var. angustifolia on 3T3-L1 adipocytes.

    Science.gov (United States)

    Woon, Shiau Mei; Seng, Yew Wei; Ling, Anna Pick Kiong; Chye, Soi Moi; Koh, Rhun Yian

    2014-03-01

    This study examined the anti-adipogenic effects of extracts of Ficus deltoidea var. deltoidia and var. angustifolia, a natural slimming aid, on 3T3-L1 adipocytes. Methanol and water extracts of leaves of the F. deltoidea varieties were analyzed to determine their total flavonoid content (TFC) and total phenolic content (TPC), respectively. The study was initiated by determining the maximum non-toxic dose (MNTD) of the methanol and water extracts for 3T3-L1 preadipocytes. Possible anti-adipogenic effects were then examined by treating 2-d post confluent 3T3-L1 preadipocytes with either methanol extract or water extract at MNTD and half MNTD (½MNTD), after which the preadipocytces were induced to form mature adipocytes. Visualisation and quantification of lipid content in mature adipocytes were carried out through oil red O staining and measurement of optical density (OD) at 520 nm, respectively. The TFCs of the methanol extracts were 1.36 and 1.97 g quercetin equivalents (QE)/100 g dry weight (DW), while the TPCs of the water extracts were 5.61 and 2.73 g gallic acid equivalents (GAE)/100 g DW for var. deltoidea and var. angustilofia, respectively. The MNTDs determined for methanol and water extracts were (300.0 ± 28.3) and (225.0 ± 21.2) µg/ml, respectively, for var. deltoidea, while much lower MNTDs [(60.0 ± 2.0) µg/ml for methanol extracts and (8.0 ± 1.0) µg/ml for water extracts] were recorded for var. angustifolia. Studies revealed that the methanol extracts of both varieties and the water extracts of var. angustifolia at either MNTD or ½MNTD significantly inhibited the maturation of preadipocytes. The inhibition of the formation of mature adipocytes indicated that leaf extracts of F. deltoidea could have potential anti-obesity effects.

  12. Isopropylnorsynephrine is a stronger lipolytic agent in human adipocytes than synephrine and other amines present in Citrus aurantium.

    Science.gov (United States)

    Mercader, Josep; Wanecq, Estelle; Chen, Jian; Carpéné, Christian

    2011-09-01

    The weight loss observed in consumers of extracts of Citrus aurantium (bitter orange) has been tentatively attributed to the lipolytic and thermogenic effects of the alkaloids abundant in the unripe fruit. Synephrine, octopamine, tyramine, and other alkaloids have been repeatedly identified and quantified in Citrus members of the Rutaceae family or in their extracts incorporated in dietary supplements for weight management. However, there are only scarce reports on their lipolytic action. This study aimed at comparing the acute lipolytic activity of synephrine, octopamine, tyramine, and N-methyltyramine in rat and human adipocytes. Maximal response to the prototypical β-adrenergic agonist isoprenaline was taken as reference in both species. In rat, octopamine was slightly more active than synephrine while tyramine and N-methyl tyramine did not stimulate-and even inhibited-lipolysis. In human adipocytes, none of these amines stimulated lipolysis when tested up to 10 μg/ml. At higher doses (≥100 μg/ml), tyramine and N-methyl tyramine induced only 20% of the maximal lipolysis and exhibited antilipolytic properties. Synephrine and octopamine were partially stimulatory at high doses. Since synephrine is more abundant than octopamine in C. aurantium, it should be the main responsible for the putative lipolytic action of the extracts claimed to mitigate obesity. Noteworthy, their common isopropyl derivative, isopropylnorsynephrine (also named isopropyloctopamine or betaphrine), was clearly lipolytic: active at 1 μg/ml and reproducing more than 60% of isoprenaline maximal effect in human adipocytes. This compound, not detected in C. aurantium, and which has few reported adverse effects to date, might be useful for in vivo triglyceride breakdown.

  13. Activation of peroxisome proliferator-activated receptor-{alpha} enhances fatty acid oxidation in human adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kawada, Teruo, E-mail: fat@kais.kyoto-u.ac.jp [Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2011-04-22

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. {yields} PPAR{alpha} activation also increased insulin-dependent glucose uptake in human adipocytes. {yields} PPAR{alpha} activation did not affect lipid accumulation in human adipocytes. {yields} PPAR{alpha} activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPAR{alpha} in adipocytes have been unclarified. We examined the functions of PPAR{alpha} using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPAR{alpha} by GW7647, a potent PPAR{alpha} agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPAR{gamma}, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPAR{alpha} activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPAR{gamma} is activated. On the other hand, PPAR{alpha} activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPAR{alpha}-dependent manner. Moreover, PPAR{alpha} activation increased the production of CO{sub 2} and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPAR{alpha} stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPAR{alpha} agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected

  14. Second messenger signaling mechanisms of the brown adipocyte thermogenic program: an integrative perspective.

    Science.gov (United States)

    Shi, Fubiao; Collins, Sheila

    2017-09-26

    β-adrenergic receptors (βARs) are well established for conveying the signal from catecholamines to adipocytes. Acting through the second messenger cyclic adenosine monophosphate (cAMP) they stimulate lipolysis and also increase the activity of brown adipocytes and the 'browning' of adipocytes within white fat depots (so-called 'brite' or 'beige' adipocytes). Brown adipose tissue mitochondria are enriched with uncoupling protein 1 (UCP1), which is a regulated proton channel that allows the dissipation of chemical energy in the form of heat. The discovery of functional brown adipocytes in humans and inducible brown-like ('beige' or 'brite') adipocytes in rodents have suggested that recruitment and activation of these thermogenic adipocytes could be a promising strategy to increase energy expenditure for obesity therapy. More recently, the cardiac natriuretic peptides and their second messenger cyclic guanosine monophosphate (cGMP) have gained attention as a parallel signaling pathway in adipocytes, with some unique features. In this review, we begin with some important historical work that touches upon the regulation of brown adipocyte development and physiology. We then provide a synopsis of some recent advances in the signaling cascades from β-adrenergic agonists and natriuretic peptides to drive thermogenic gene expression in the adipocytes and how these two pathways converge at a number of unexpected points. Finally, moving from the physiologic hormonal signaling, we discuss yet another level of control downstream of these signals: the growing appreciation of the emerging roles of non-coding RNAs as important regulators of brown adipocyte formation and function. In this review, we discuss new developments in our understanding of the signaling mechanisms and factors including new secreted proteins and novel non-coding RNAs that control the function as well as the plasticity of the brown/beige adipose tissue as it responds to the energy needs and environmental

  15. Limited OXPHOS capacity in white adipocytes is a hallmark of obesity in laboratory mice irrespective of the glucose tolerance status

    Directory of Open Access Journals (Sweden)

    Theresa Schöttl

    2015-09-01

    Conclusion: Reduced mitochondrial respiratory capacity in white adipocytes is a hallmark of murine obesity irrespective of the glucose tolerance status. Impaired respiratory capacity in white adipocytes solely is not sufficient for the development of systemic glucose intolerance.

  16. Transcriptional and epigenetic mechanisms underlying enhanced in vitro adipocyte differentiation by the brominated flame retardant BDE-47

    DEFF Research Database (Denmark)

    Kamstra, Jorke H; Hruba, Eva; Blumberg, Bruce

    2014-01-01

    . The mechanisms by which EDCs direct preadipocytes to form adipocytes are poorly understood. Here, we examined transcriptional and epigenetic mechanisms underlying the induction of in vitro adipocyte differentiation by BDE-47. Quantitative high content microscopy revealed concentration-dependent enhanced...

  17. Acute Genome-wide effects of Rosiglitazone on PPARγ transcriptional networks in Adipocytes

    DEFF Research Database (Denmark)

    Haakonsson, Anders Kristian; Madsen, Maria Stahl; Nielsen, Ronni

    2013-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) is a master regulator of adipocyte differentiation, and genome-wide studies indicate that it is involved in the induction of most adipocyte genes. Here we report, for the first time, the acute effects of the synthetic PPARγ agonist rosiglitazon...

  18. SIK2 regulates CRTCs, HDAC4 and glucose uptake in adipocytes

    DEFF Research Database (Denmark)

    Henriksson, Emma; Säll, Johanna; Gormand, Amélie

    2015-01-01

    Salt-inducible kinase 2 (SIK2) is an AMPK-related kinase abundantly expressed in adipose tissue. Our aim was to identify molecular targets and functions of SIK2 in adipocytes, and to address the role of PKA-phosphorylation of SIK2 on Ser358. Modulation of SIK2 in adipocytes resulted in altered...

  19. Human ADMC-Derived Adipocyte Thermogenic Capacity Is Regulated by IL-4 Receptor.

    Science.gov (United States)

    Lizcano, Fernando; Vargas, Diana; Gómez, Ángela; Torrado, Astrid

    2017-01-01

    Type two innate immune system is anti-inflammatory and may play an important role as the means whereby "browning" is induced in subcutaneous adipocytes. It was shown that IL-4 may influence the fate of adipose cell precursors by promoting differentiation towards more thermogenic adipocytes in mice. Here, we investigated the influence of IL-4 and IL-4 receptor, a type two immune cytokine pathway, on the metabolic activity and thermogenic potential of human adipocytes differentiated from adipose-derived mesenchymal stem cells (ADMSCs) obtained from subcutaneous samples of healthy women undergoing abdominoplasty. Western blot analysis, qPCR, and biochemical analyses were performed 10 days after ADMSC differentiation into mature adipocytes was induced. IL-4 receptor was expressed in both precursor and differentiated adipocytes, and IL-4 treatment increased phosphorylation Y641 of signal transducer and activator of transcription 6 (STAT6) in both cell types. IL-4 treatment also increased expression of thermogenic proteins PGC-1 α , UCP-1, and CITED1. In addition, IL-4 increased the secretion of adiponectin, leptin, and FGF21 and promoted lipolysis in differentiated adipocytes. In conclusion, IL-4 may directly modulate differentiation of human adipocytes towards a beige phenotype acting through IL-4 receptors on both adipose precursors and differentiated human adipocytes, metabolic effect that must be considered in some antiallergic drugs.

  20. Human ADMC-Derived Adipocyte Thermogenic Capacity Is Regulated by IL-4 Receptor

    Directory of Open Access Journals (Sweden)

    Fernando Lizcano

    2017-01-01

    Full Text Available Type two innate immune system is anti-inflammatory and may play an important role as the means whereby “browning” is induced in subcutaneous adipocytes. It was shown that IL-4 may influence the fate of adipose cell precursors by promoting differentiation towards more thermogenic adipocytes in mice. Here, we investigated the influence of IL-4 and IL-4 receptor, a type two immune cytokine pathway, on the metabolic activity and thermogenic potential of human adipocytes differentiated from adipose-derived mesenchymal stem cells (ADMSCs obtained from subcutaneous samples of healthy women undergoing abdominoplasty. Western blot analysis, qPCR, and biochemical analyses were performed 10 days after ADMSC differentiation into mature adipocytes was induced. IL-4 receptor was expressed in both precursor and differentiated adipocytes, and IL-4 treatment increased phosphorylation Y641 of signal transducer and activator of transcription 6 (STAT6 in both cell types. IL-4 treatment also increased expression of thermogenic proteins PGC-1α, UCP-1, and CITED1. In addition, IL-4 increased the secretion of adiponectin, leptin, and FGF21 and promoted lipolysis in differentiated adipocytes. In conclusion, IL-4 may directly modulate differentiation of human adipocytes towards a beige phenotype acting through IL-4 receptors on both adipose precursors and differentiated human adipocytes, metabolic effect that must be considered in some antiallergic drugs.

  1. A novel crosstalk between Alk7 and cGMP signaling differentially regulates brown adipocyte function

    Directory of Open Access Journals (Sweden)

    Aileen Balkow

    2015-08-01

    Conclusions: We found a so far unknown crosstalk between cGMP and Alk7 signaling pathways. Tight regulation of Alk7 is required for efficient differentiation of brown adipocytes. Alk7 has differential effects on adipogenic differentiation and the development of the thermogenic program in brown adipocytes.

  2. Characterization of murine melanocortin receptors mediating adipocyte lipolysis and examination of signalling pathways involved

    DEFF Research Database (Denmark)

    Møller, Cathrine Laustrup; Raun, Kirsten; Jacobsen, Marianne Lambert

    2011-01-01

    hormone (a-MSH) generated from proopiomelanocortin (POMC), as well as synthetic MSH analogues to stimulate lipolysis in murine 3T3-L1 adipocytes it is shown that MC2R and MC5R are lipolytic mediators in differentiated 3T3-L1 adipocytes. Involvement of cAMP, phosphorylated extracellular signal...

  3. In-depth analysis of the adipocyte proteome by mass spectrometry and bioinformatics

    DEFF Research Database (Denmark)

    Adachi, Jun; Kumar, Chanchal; Zhang, Yanling

    2007-01-01

    , mitochondria, membrane, and cytosol of 3T3-L1 adipocytes. We identified 3,287 proteins while essentially eliminating false positives, making this one of the largest high confidence proteomes reported to date. Comprehensive bioinformatics analysis revealed that the adipocyte proteome, despite its specialized...

  4. Nuclear factor-κB is a common upstream signal for growth differentiation factor-5 expression in brown adipocytes exposed to pro-inflammatory cytokines and palmitate

    International Nuclear Information System (INIS)

    Hinoi, Eiichi; Iezaki, Takashi; Ozaki, Kakeru; Yoneda, Yukio

    2014-01-01

    Highlights: • GDF5 expression is up-regulated by IL-1β, TNF-α and palmitate in brown pre-adipocytes. • NF-κB stimulates promoter activity and expression of GDF5 in brown pre-adipocytes. • Recruitment of NF-κB to the GDF5 promoter is facilitated in BAT from ob/ob mice. • An NF-κB inhibitor prevents upregulation of GDF5 expression in brown pre-adipocytes. - Abstract: We have previously demonstrated that genetic and acquired obesity similarly led to drastic upregulation in brown adipose tissue (BAT), rather than white adipose tissue, of expression of both mRNA and corresponding protein for the bone morphogenic protein/growth differentiation factor (GDF) member GDF5 capable of promoting brown adipogenesis. In this study, we evaluated expression profiles of GDF5 in cultured murine brown pre-adipocytes exposed to pro-inflammatory cytokines and free fatty acids (FFAs), which are all shown to play a role in the pathogenesis of obesity. Both interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were effective in up-regulating GDF5 expression in a concentration-dependent manner, while similar upregulation was seen in cells exposed to the saturated FFA palmitate, but not to the unsaturated FFA oleate. In silico analysis revealed existence of the putative nuclear factor-κB (NF-κB) binding site in the 5′-flanking region of mouse GDF5, whereas introduction of NF-κB subunits drastically facilitated both promoter activity and expression of GDF5 in brown pre-adipocytes. Chromatin immunoprecipitation analysis confirmed significant facilitation of the recruitment of NF-κB to the GDF5 promoter in lysed extracts of BAT from leptin-deficient ob/ob obese mice. Upregulation o GDF5 expression was invariably inhibited by an NF-κB inhibitor in cultured brown pre-adipocytes exposed to IL-1β, TNF-α and palmitate. These results suggest that obesity leads to upregulation of GDF5 expression responsible for the promotion of brown adipogenesis through a mechanism

  5. Nuclear factor-κB is a common upstream signal for growth differentiation factor-5 expression in brown adipocytes exposed to pro-inflammatory cytokines and palmitate

    Energy Technology Data Exchange (ETDEWEB)

    Hinoi, Eiichi; Iezaki, Takashi; Ozaki, Kakeru; Yoneda, Yukio, E-mail: yyoneda@p.kanazawa-u.ac.jp

    2014-10-03

    Highlights: • GDF5 expression is up-regulated by IL-1β, TNF-α and palmitate in brown pre-adipocytes. • NF-κB stimulates promoter activity and expression of GDF5 in brown pre-adipocytes. • Recruitment of NF-κB to the GDF5 promoter is facilitated in BAT from ob/ob mice. • An NF-κB inhibitor prevents upregulation of GDF5 expression in brown pre-adipocytes. - Abstract: We have previously demonstrated that genetic and acquired obesity similarly led to drastic upregulation in brown adipose tissue (BAT), rather than white adipose tissue, of expression of both mRNA and corresponding protein for the bone morphogenic protein/growth differentiation factor (GDF) member GDF5 capable of promoting brown adipogenesis. In this study, we evaluated expression profiles of GDF5 in cultured murine brown pre-adipocytes exposed to pro-inflammatory cytokines and free fatty acids (FFAs), which are all shown to play a role in the pathogenesis of obesity. Both interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were effective in up-regulating GDF5 expression in a concentration-dependent manner, while similar upregulation was seen in cells exposed to the saturated FFA palmitate, but not to the unsaturated FFA oleate. In silico analysis revealed existence of the putative nuclear factor-κB (NF-κB) binding site in the 5′-flanking region of mouse GDF5, whereas introduction of NF-κB subunits drastically facilitated both promoter activity and expression of GDF5 in brown pre-adipocytes. Chromatin immunoprecipitation analysis confirmed significant facilitation of the recruitment of NF-κB to the GDF5 promoter in lysed extracts of BAT from leptin-deficient ob/ob obese mice. Upregulation o GDF5 expression was invariably inhibited by an NF-κB inhibitor in cultured brown pre-adipocytes exposed to IL-1β, TNF-α and palmitate. These results suggest that obesity leads to upregulation of GDF5 expression responsible for the promotion of brown adipogenesis through a mechanism

  6. Raspberry ketone induces brown-like adipocyte formation through suppression of autophagy in adipocytes and adipose tissue.

    Science.gov (United States)

    Leu, Sy-Ying; Tsai, Yung-Chieh; Chen, Wen-Chi; Hsu, Chih-Hsiung; Lee, Yen-Mei; Cheng, Pao-Yun

    2018-02-13

    Promoting white adipose tissue (WAT) to acquire brown-like characteristics is a promising approach for obesity treatment. Although raspberry ketone (RK) has been reported to possess antiobesity activity, its effects on the formation of brown-like adipocytes remain unclear. Therefore, we investigated the effects and underlying mechanism of RK on WAT browning in 3T3-L1 adipocytes and rats with ovariectomy (Ovx)-induced obesity. RK (100 μM) significantly induced browning of 3T3-L1 cells by increasing mitochondrial biogenesis and the expression of browning-specific proteins (PR domain containing 16, PRDM16; peroxisome proliferator-activated receptor gamma coactivator 1-alpha, PGC-1α; uncoupling protein-1, UCP-1) and lipolytic enzymes (hormone-sensitive lipase and adipose triglyceride lipase). RK significantly reduced the expression of the autophagy-related protein Atg12 and increased the expression of p62 and heme oxygenase 1 (HO-1). Additionally, these effects of RK were reversed by the HO-1 inhibitor SnPP (20 μM). In addition, RK (160 mg/kg, gavage, for 8 weeks) significantly reduced body weight gain (Ovx+RK, 191.8 ± 4.6 g vs. Ovx, 223.6 ± 5.9; P < .05), food intake, the amount of inguinal adipose tissue (Ovx+RK, 9.05 ± 1.1 g vs Ovx, 12.9 ± 0.92 g; P < .05) and the size of white adipocytes in Ovx rats. Moreover, compared to expression in the Ovx group, the levels of browning-specific proteins were significantly higher and the levels of autophagy-related proteins were significantly lower in the Ovx+RK group. Therefore, this study elucidated the mechanism associated with RK-induced WAT browning and thus provides evidence to support the clinical use of RK for obesity treatment. Copyright © 2018. Published by Elsevier Inc.

  7. Genome-Wide Insights into the Development and Function of Thermogenic Adipocytes

    DEFF Research Database (Denmark)

    Loft, Anne; Forss, Isabel; Mandrup, Susanne

    2017-01-01

    Brown and brown-like adipocytes are specialized adipocytes with a high capacity to convert metabolic energy to heat. This function is not only eminent in supporting organismal thermogenesis, but may also have potential in the fight against obesity. The latter has spurred a massive interest in und...... the genomic programming of white adipocytes. Furthermore, we discuss how the integration of genomic data can be used to discover novel transcriptional pathways that may be modulated as part of therapeutic strategies for the treatment of obesity.......Brown and brown-like adipocytes are specialized adipocytes with a high capacity to convert metabolic energy to heat. This function is not only eminent in supporting organismal thermogenesis, but may also have potential in the fight against obesity. The latter has spurred a massive interest...

  8. Genome-Wide Insights into the Development and Function of Thermogenic Adipocytes.

    Science.gov (United States)

    Loft, Anne; Forss, Isabel; Mandrup, Susanne

    2017-02-01

    Brown and brown-like adipocytes are specialized adipocytes with a high capacity to convert metabolic energy to heat. This function is not only eminent in supporting organismal thermogenesis, but may also have potential in the fight against obesity. The latter has spurred a massive interest in understanding the development and regulation of these thermogenic adipocytes. Here, we review how genome-wide studies based on next-generation sequencing have provided insight into how the chromatin and transcriptional landscapes are established in thermogenic adipocytes and how thermogenic signals can change the genomic programming of white adipocytes. Furthermore, we discuss how the integration of genomic data can be used to discover novel transcriptional pathways that may be modulated as part of therapeutic strategies for the treatment of obesity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. PPAR{alpha} does not suppress muscle-associated gene expression in brown adipocytes but does influence expression of factors that fingerprint the brown adipocyte

    Energy Technology Data Exchange (ETDEWEB)

    Walden, Tomas B.; Petrovic, Natasa [The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm (Sweden); Nedergaard, Jan, E-mail: jan@metabol.su.se [The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91 Stockholm (Sweden)

    2010-06-25

    Brown adipocytes and myocytes develop from a common adipomyocyte precursor. PPAR{alpha} is a nuclear receptor important for lipid and glucose metabolism. It has been suggested that in brown adipose tissue, PPAR{alpha} represses the expression of muscle-associated genes, in this way potentially acting to determine cell fate in brown adipocytes. To further understand the possible role of PPAR{alpha} in these processes, we measured expression of muscle-associated genes in brown adipose tissue and brown adipocytes from PPAR{alpha}-ablated mice, including structural genes (Mylpf, Tpm2, Myl3 and MyHC), regulatory genes (myogenin, Myf5 and MyoD) and a myomir (miR-206). However, in our hands, the expression of these genes was not influenced by the presence or absence of PPAR{alpha}, nor by the PPAR{alpha} activator Wy-14,643. Similarly, the expression of genes common for mature brown adipocyte and myocytes (Tbx15, Meox2) were not affected. However, the brown adipocyte-specific regulatory genes Zic1, Lhx8 and Prdm16 were affected by PPAR{alpha}. Thus, it would not seem that PPAR{alpha} represses muscle-associated genes, but PPAR{alpha} may still play a role in the regulation of the bifurcation of the adipomyocyte precursor into a brown adipocyte or myocyte phenotype.

  10. Evaluation of a laminin-alginate biomaterial, adipocytes, and adipocyte-derived stem cells interaction in animal autologous fat grafting model using 7-Tesla magnetic resonance imaging.

    Science.gov (United States)

    Chen, Yo-Shen; Hsueh, Yu-Sheng; Chen, Yen-Yu; Lo, Cheng-Yu; Tai, Hao-Chih; Lin, Feng-Huei

    2017-01-01

    Biomaterials are often added to autologous fat grafts both as supporting matrices for the grafted adipocytes and as cell carrier for adipose-derived stem cells (ADSCs). This in vivo study used an autologous fat graft model to test a lamininalginate biomaterial, adipocytes, and ADSCs in immune-competent rats. We transplanted different combinations of shredded autologous adipose tissue [designated "A" for adipose tissue]), laminin-alginate beads [designated "B" for bead], and ADSCs [designated "C" for cell]) into the backs of 15 Sprague-Dawley rats. Group A received only adipocytes, Group B received only laminin-alginate beads, Group AB received adipocytes mixed with laminin-alginate beads, Group BC received laminin-alginate beads encapsulating ADSCs, and Group ABC received adipocytes and laminin-alginate beads containing ADSCs. Seven-tesla magnetic resonance imaging was used to evaluate the rats at the 1st, 6th, and 12th weeks after transplantation. At the 12th week, the rats were sacrificed and the implanted materials were retrieved for gross examination and histological evaluation. The results based on MRI, gross evaluation, and histological data all showed that implants in Group ABC had better resorption of the biomaterial, improved survival of the grafted adipocytes, and adipogenic differentiation of ADSCs. Volume retention of grafts in Group ABC (89%) was also significantly greater than those in Group A (58%) (p < 0.01). Our findings support that the combination of shredded adipose tissue with ADSCs in laminin-alginate beads provided the best overall outcome.

  11. Spexin is a Novel Human Peptide that Reduces Adipocyte Uptake of Long Chain Fatty Acids and Causes Weight Loss in Rodents with Diet-induced Obesity*

    Science.gov (United States)

    Walewski, José L.; Ge, Fengxia; Lobdell, Harrison; Levin, Nancy; Schwartz, Gary J.; Vasselli, Joseph; Pomp, Afons; Dakin, Gregory; Berk, Paul D.

    2014-01-01

    Objective Microarray studies identified Ch12:orf39 (Spexin) as the most dysregulated gene in obese human fat. Therefore we examined its role in obesity pathogenesis. Design and Methods Spexin effects on food intake, meal patterns, body weight, Respiratory Exchange Ratio (RER), and locomotor activity were monitored electronically in C57BL/6J mice or Wistar rats with dietary-induced obesity (DIO). Its effects on adipocyte [3H]-oleate uptake were determined. Results In humans, Spexin gene expression was down-regulated 14.9-fold in obese omental and subcutaneous fat. Circulating Spexin changed in parallel, correlating (r = −0.797) with Leptin. In rats, Spexin (35 μg/kg/day s.c) reduced caloric intake ~32% with corresponding weight loss. Meal patterns were unaffected. In mice, Spexin (25 μg/kg/day i.p.) significantly reduced the RER at night, and increased locomotion. Spexin incubation in vitro significantly inhibited facilitated fatty acid (FA) uptake into DIO mouse adipocytes. Conditioned taste aversion testing (70μg/kg/day i.p.) demonstrated no aversive Spexin effects. Conclusions Spexin gene expression is markedly down-regulated in obese human fat. The peptide produces weight loss in DIO rodents. Its effects on appetite and energy regulation are presumably central; those on adipocyte FA uptake appear direct and peripheral. Spexin is a novel hormone involved in weight regulation, with potential for obesity therapy. PMID:24550067

  12. Spexin is a novel human peptide that reduces adipocyte uptake of long chain fatty acids and causes weight loss in rodents with diet-induced obesity.

    Science.gov (United States)

    Walewski, José L; Ge, Fengxia; Lobdell, Harrison; Levin, Nancy; Schwartz, Gary J; Vasselli, Joseph R; Pomp, Afons; Dakin, Gregory; Berk, Paul D

    2014-07-01

    Microarray studies identified Ch12:orf39 (Spexin) as the most down-regulated gene in obese human fat. Therefore, we examined its role in obesity pathogenesis. Spexin effects on food intake, meal patterns, body weight, respiratory exchange ratio (RER), and locomotor activity were monitored electronically in C57BL/6J mice or Wistar rats with diet-induced obesity (DIO). Its effects on adipocyte [(3)H]-oleate uptake were determined. In humans, Spexin gene expression was down-regulated 14.9-fold in obese omental and subcutaneous fat. Circulating Spexin changed in parallel, correlating (r = -0.797) with Leptin. In rats, Spexin (35 µg/kg/day SC) reduced caloric intake ∼32% with corresponding weight loss. Meal patterns were unaffected. In mice, Spexin (25 µg/kg/day IP) significantly reduced the RER at night, and increased locomotion. Spexin incubation in vitro significantly inhibited facilitated fatty acid (FA) uptake into DIO mouse adipocytes. Conditioned taste aversion testing (70 µg/kg/day IP) demonstrated no aversive Spexin effects. Spexin gene expression is markedly down-regulated in obese human fat. The peptide produces weight loss in DIO rodents. Its effects on appetite and energy regulation are presumably central; those on adipocyte FA uptake appear direct and peripheral. Spexin is a novel hormone involved in weight regulation, with potential for obesity therapy. Copyright © 2014 The Obesity Society.

  13. γ-Oryzanol Enhances Adipocyte Differentiation and Glucose Uptake

    Directory of Open Access Journals (Sweden)

    Chang Hwa Jung

    2015-06-01

    Full Text Available Recent studies show that brown rice improves glucose intolerance and potentially the risk of diabetes, although the underlying molecular mechanisms remain unclear. One of the phytochemicals found in high concentration in brown rice is γ-oryzanol (Orz, a group of ferulic acid esters of phytosterols and triterpene alcohols. Here, we found that Orz stimulated differentiation of 3T3-L1 preadipocytes and increased the protein expression of adipogenic marker genes such as peroxisome proliferator-activated receptor gamma (PPAR-γ and CCAAT/enhanced binding protein alpha (C/EBPα. Moreover, Orz significantly increased the glucose uptake in insulin-resistant cells and translocation of glucose transporter type 4 (GLUT4 from the cytosol to the cell surface. To investigate the mechanism by which Orz stimulated cell differentiation, we examined its effects on cellular signaling of the mammalian target of rapamycin complex 1 (mTORC1, a central mediator of cellular growth and proliferation. The Orz treatment increased mTORC1 kinase activity based on phosphorylation of 70-kDa ribosomal S6 kinase 1 (S6K1. The effect of Orz on adipocyte differentiation was dependent on mTORC1 activity because rapamycin blocks cell differentiation in Orz-treated cells. Collectively, our results indicate that Orz stimulates adipocyte differentiation, enhances glucose uptake, and may be associated with cellular signaling mediated by PPAR-γ and mTORC1.

  14. The Mechanism of White and Brown Adipocyte Differentiation

    Directory of Open Access Journals (Sweden)

    Hironori Nakagami

    2013-04-01

    Full Text Available Obesity gives vent to many diseases such as type 2 diabetes, hypertension, and hyperlipidemia, being considered as the main causes of mortality and morbidity worldwide. The pathogenesis and pathophysiology of metabolic syndrome can well be understood by studying the molecular mechanisms that control the development and function of adipose tissue. In human body, exist two types of adipose tissue, the white and the brown one, which are reported to play various roles in energy homeostasis. The major and most efficient storage of energy occurs in the form of triglycerides in white adipose tissue while brown adipose tissue actively participates in both basal and inducible energy consumption in the form of thermogenesis. Recent years have observed a rapid and greater interest towards developmental plasticity and therapeutic potential of stromal cells those isolated from adipose tissue. The adipocyte differentiation involves a couple of regulators in the white or brown adipogenesis. Peroxisome proliferators-activated receptor-γ actively participates in regulating carbohydrate and lipid metabolism, and also acts as main regulator of both white and brown adipogenesis. This review based on our recent research, seeks to highlight the adipocyte differentiation.

  15. Effects of arsenic on adipocyte metabolism: Is arsenic an obesogen?

    Science.gov (United States)

    Ceja-Galicia, Zeltzin A; Daniel, Alberto; Salazar, Ana María; Pánico, Pablo; Ostrosky-Wegman, Patricia; Díaz-Villaseñor, Andrea

    2017-09-05

    The environmental obesogen model proposes that in addition to a high-calorie diet and diminished physical activity, other factors such as environmental pollutants and chemicals are involved in the development of obesity. Although arsenic has been recognized as a risk factor for Type 2 Diabetes with a specific mechanism, it is still uncertain whether arsenic is also an obesogen. The impairment of white adipose tissue (WAT) metabolism is crucial in the onset of obesity, and distinct studies have evaluated the effects of arsenic on it, however only in some of them for obesity-related purposes. Thus, the known effects of arsenic on WAT/adipocytes were integrated based on the diverse metabolic and physiological processes that occur in WAT and are altered in obesity, specifically: adipocyte growth, adipokine secretion, lipid metabolism, and glucose metabolism. The currently available information suggests that arsenic can negatively affect WAT metabolism, resulting in arsenic being a potential obesogen. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Loss of Adipocyte VEGF Impairs Endurance Exercise Capacity in Mice.

    Science.gov (United States)

    Zachwieja, Nicole J; O'Connell, Grant C; Stricker, Janelle C; Allen, Jessica; Vona-Davis, Linda; Bryner, Randall; Mandler, William; Olfert, I Mark

    2015-11-01

    Reducing vascular endothelial growth factor (VEGF) in adipose tissue alters adipose vascularity and metabolic homeostasis. We hypothesized that this would also affect metabolic responses during exercise-induced stress and that adipocyte-specific VEGF-deficient (adipoVEGF-/-) mice would have impaired endurance capacity. Endurance exercise capacity in adipoVEGF-/- (n = 10) and littermate control (n = 11) mice was evaluated every 4 wk between 6 and 24 wk of age using a submaximal endurance run to exhaustion at 20 m·min(-1) at 10° incline. Maximal running speed, using incremental increases in speed at 30-s intervals, was tested at 25 and 37 wk of age. White and brown adipose tissue capillarity were reduced by 40% in adipoVEGF-/-, and no difference in skeletal muscle capillarity was observed. Endurance run time to exhaustion was 30% lower in adipoVEGF-/- compared with that in controls at all time points (P speed was observed between the groups. After exercise (1 h at 50% maximum running speed), adipoVEGF-/- mice displayed lower circulating insulin (P endurance exercise, which likely reduced endurance performance. Surprisingly, we also found an unchanged basal blood glucose despite lower circulating insulin in adipoVEGF-/- mice, suggesting that loss of adipocyte VEGF can blunt insulin release and/or increase basal insulin sensitivity.

  17. Lats2 modulates adipocyte proliferation and differentiation via hippo signaling.

    Directory of Open Access Journals (Sweden)

    Yang An

    Full Text Available First identified in Drosophila and highly conserved in mammals, the Hippo pathway controls organ size. Lats2 is one of the core kinases of the Hippo pathway and plays major roles in cell proliferation by interacting with the downstream transcriptional cofactors YAP and TAZ. Although the function of the Hippo pathway and Lats2 is relatively well understood in several tissues and organs, less is known about the function of Lats2 and Hippo signaling in adipose development. Here, we show that Lats2 is an important modulator of adipocyte proliferation and differentiation via Hippo signaling. Upon activation, Lats2 phosphorylates YAP and TAZ, leading to their retention in the cytoplasm, preventing them from activating the transcription factor TEAD in the nucleus. Because TAZ remains in the cytoplasm, PPARγ regains its transcriptional activity. Furthermore, cytoplasmic TAZ acts as an inhibitor of Wnt signaling by suppressing DVL2, thereby preventing β-catenin from entering the nucleus to stimulate TCF/LEF transcriptional activity. The above effects contribute to the phenotype of repressed proliferation and accelerated differentiation in adipocytes. Thus, Lats2 regulates the balance between proliferation and differentiation during adipose development. Interestingly, our study provides evidence that Lats2 not only negatively modulates cell proliferation but also positively regulates cell differentiation.

  18. Regulation of the pro-inflammatory cytokine osteopontin by GIP in adipocytes - A role for the transcription factor NFAT and phosphodiesterase 3B

    Energy Technology Data Exchange (ETDEWEB)

    Omar, Bilal [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden); Banke, Elin, E-mail: elin.banke@med.lu.se [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden); Guirguis, Emilia [Cardiovascular Pulmonary Branch, NHLBI, NIH, Bethesda, MD (United States); Aakesson, Lina [Department of Clinical Sciences, Diabetes and Celiac Disease Unit, Clinical Research Centre, Lund University, Malmoe (Sweden); Manganiello, Vincent [Cardiovascular Pulmonary Branch, NHLBI, NIH, Bethesda, MD (United States); Lyssenko, Valeriya; Groop, Leif [Department of Clinical Sciences, Diabetes and Endocrinology, Clinical Research Centre, Lund University, Malmoe (Sweden); Gomez, Maria F. [Department of Clinical Sciences, Vascular ET Coupling, Clinical Research Centre, Lund University, Malmoe (Sweden); Degerman, Eva [Department of Experimental Medical Sciences, Diabetes, Metabolism and Endocrinology, Biomedical Center, Lund University, Lund (Sweden)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. Black-Right-Pointing-Pointer GIP-induced osteopontin expression is NFAT-dependent. Black-Right-Pointing-Pointer Osteopontin expression is PDE3-dependent. Black-Right-Pointing-Pointer Osteopontin expression is increased in PDE3B KO mice. -- Abstract: The incretin - glucose-dependent insulinotropic polypeptide (GIP) - and the pro-inflammatory cytokine osteopontin are known to have important roles in the regulation of adipose tissue functions. In this work we show that GIP stimulates lipogenesis and osteopontin expression in primary adipocytes. The GIP-induced increase in osteopontin expression was inhibited by the NFAT (the transcription factor nuclear factor of activated T-cells) inhibitor A-285222. Also, the NFAT kinase glycogen synthase kinase (GSK) 3 was upregulated by GIP. To test whether cAMP might be involved in GIP-mediated effects on osteopontin a number of strategies were used. Thus, the {beta}3-adrenergic receptor agonist CL316,243 stimulated osteopontin expression, an effects which was mimicked by OPC3911, a specific inhibitor of phosphodiesterase 3. Furthermore, treatment of phosphodiesterase 3B knock-out mice with CL316,243 resulted in a dramatic upregulation of osteopontin in adipose tissue which was not the case in wild-type mice. In summary, we delineate mechanisms by which GIP stimulates osteopontin in adipocytes. Given the established link between osteopontin and insulin resistance, our data suggest that GIP by stimulating osteopontin expression, also could promote insulin resistance in adipocytes.

  19. Thyroxine 5'-deiodination mediates norepinephrine-induced lipogenesis in dispersed brown adipocytes.

    Science.gov (United States)

    Bianco, A C; Carvalho, S D; Carvalho, C R; Rabelo, R; Moriscot, A S

    1998-02-01

    In euthyroid rats, maximal sympathetic nervous system stimulation (e.g. during cold exposure) results in a 3- to 4-fold increase in brown adipose tissue lipogenesis, a response that is blunted in hypothyroid rats. To further investigate this phenomenon, the role of local type II 5'-deiodinase (5'-DII) was studied in freshly isolated brown adipocytes. In a typical experiment, 1.5 x 10(6) cells were incubated for up to 48 h in a water-saturated 5% CO2-95% O2 atmosphere. After incubation with medium alone or with different concentrations of T4, T3, and/or norepinephrine (NE), lipogenesis was studied by measuring 1) the rate of fatty acid synthesis as reflected by 3H2O incorporation into lipids and 2) the activity of key rate-limiting enzymes, i.e. acetyl coenzyme A carboxylase and malic enzyme, and the results are reported in terms of DNA content per tube. Lipogenesis decreased progressively over time (approximately 40%) when no additions were made to the incubation medium. T4 or T3 partially prevented that inhibition at physiological concentrations (65 x 10[-9] and 0.77 x 10[-9] M, respectively), whereas a receptor-saturating concentration of T3, (154 x 10[-9] M) doubled the lipogenesis rate. The addition of 10(-6) M NE inhibited lipogenesis acutely (approximately 50% by 12 h) and was followed by a progressive stimulation that reached approximately 2-fold by 48 h, but only in the presence of T4. Furthermore, NE did not attenuate T3 (154 x 10[-9] M)-induced lipogenesis. Both the inhibition and the stimulation of lipogenesis caused by NE showed a strong dose-response relationship within the range of 10(-11)-10(-5) M. The role of local 5'-DII was further tested by incubating brown adipocytes with 10(-6) M NE and T4 (65 x 10[-9] M) in the presence of 100 microM iopanoic acid, a potent inhibitor of 5'-DII. Although iopanoic acid did not affect the T3 stimulation of lipogenesis, it did block the approximately 2-fold stimulation of lipogenesis triggered by NE in the

  20. Citrus aurantium flavonoids inhibit adipogenesis through the Akt signaling pathway in 3T3-L1 cells

    Directory of Open Access Journals (Sweden)

    Kim Gon-Sup

    2012-04-01

    Full Text Available Abstract Background Obesity is a health hazard that is associated with a number of diseases and metabolic abnormalities, such as type-2 diabetes, hypertension, dyslipidemia, and coronary heart disease. In the current study, we investigated the effects of Citrus aurantium flavonoids (CAF on the inhibition of adipogenesis and adipocyte differentiation in 3T3-L1 cells. Methods During adipocyte differentiation, 3T3-L1 cells were treated with 0, 10, and 50 μg/ml CAF, and then the mRNA and protein expression of adipogenesis-related genes was assayed. We examined the effect of CAF on level of phosphorylated Akt in 3T3-L1 cells treated with CAF at various concentrations during adipocyte differentiation. Results The insulin-induced expression of C/EBPβ and PPARγ mRNA and protein were significantly down-regulated in a dose-dependent manner following CAF treatment. CAF also dramatically decreased the expression of C/EBPα, which is essential for the acquisition of insulin sensitivity by adipocytes. Moreover, the expression of the aP2 and FAS genes, which are involved in lipid metabolism, decreased dramatically upon treatment with CAF. Interestingly, CAF diminished the insulin-stimulated serine phosphorylation of Akt (Ser473 and GSK3β (Ser9, which may reduce glucose uptake in response to insulin and lipid accumulation. Furthermore, CAF not only inhibited triglyceride accumulation during adipogenesis but also contributed to the lipolysis of adipocytes. Conclusions In the present study, we demonstrate that CAF suppressed adipogenesis in 3T3-L1 adipocytes. Our results indicated that CAF down-regulates the expression of C/EBPβ and subsequently inhibits the activation of PPARγ and C/EBPα. The anti-adipogenic activity of CAF was mediated by the inhibition of Akt activation and GSK3β phosphorylation, which induced the down-regulation of lipid accumulation and lipid metabolizing genes, ultimately inhibiting adipocyte differentiation.

  1. Citrus aurantium flavonoids inhibit adipogenesis through the Akt signaling pathway in 3T3-L1 cells.

    Science.gov (United States)

    Kim, Gon-Sup; Park, Hyoung Joon; Woo, Jong-Hwa; Kim, Mi-Kyeong; Koh, Phil-Ok; Min, Wongi; Ko, Yeoung-Gyu; Kim, Chung-Hei; Won, Chung-Kil; Cho, Jae-Hyeon

    2012-04-03

    Obesity is a health hazard that is associated with a number of diseases and metabolic abnormalities, such as type-2 diabetes, hypertension, dyslipidemia, and coronary heart disease. In the current study, we investigated the effects of Citrus aurantium flavonoids (CAF) on the inhibition of adipogenesis and adipocyte differentiation in 3T3-L1 cells. During adipocyte differentiation, 3T3-L1 cells were treated with 0, 10, and 50 μg/ml CAF, and then the mRNA and protein expression of adipogenesis-related genes was assayed. We examined the effect of CAF on level of phosphorylated Akt in 3T3-L1 cells treated with CAF at various concentrations during adipocyte differentiation. The insulin-induced expression of C/EBPβ and PPARγ mRNA and protein were significantly down-regulated in a dose-dependent manner following CAF treatment. CAF also dramatically decreased the expression of C/EBPα, which is essential for the acquisition of insulin sensitivity by adipocytes. Moreover, the expression of the aP2 and FAS genes, which are involved in lipid metabolism, decreased dramatically upon treatment with CAF. Interestingly, CAF diminished the insulin-stimulated serine phosphorylation of Akt (Ser473) and GSK3β (Ser9), which may reduce glucose uptake in response to insulin and lipid accumulation. Furthermore, CAF not only inhibited triglyceride accumulation during adipogenesis but also contributed to the lipolysis of adipocytes. In the present study, we demonstrate that CAF suppressed adipogenesis in 3T3-L1 adipocytes. Our results indicated that CAF down-regulates the expression of C/EBPβ and subsequently inhibits the activation of PPARγ and C/EBPα. The anti-adipogenic activity of CAF was mediated by the inhibition of Akt activation and GSK3β phosphorylation, which induced the down-regulation of lipid accumulation and lipid metabolizing genes, ultimately inhibiting adipocyte differentiation.

  2. Models of lipid droplets growth and fission in adipocyte cells

    International Nuclear Information System (INIS)

    Boschi, Federico; Rizzatti, Vanni; Zamboni, Mauro; Sbarbati, Andrea

    2015-01-01

    Lipid droplets (LD) are spherical cellular inclusion devoted to lipids storage. It is well known that excessive accumulation of lipids leads to several human worldwide diseases like obesity, type 2 diabetes, hepatic steatosis and atherosclerosis. LDs' size range from fraction to one hundred of micrometers in adipocytes and is related to the lipid content, but their growth is still a puzzling question. It has been suggested that LDs can grow in size due to the fusion process by which a larger LD is obtained by the merging of two smaller LDs, but these events seems to be rare and difficult to be observed. Many other processes are thought to be involved in the number and growth of LDs, like the de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets. Moreover the number and size of LDs are influenced by the catabolism and the absorption or interaction with other organelles. The comprehension of these processes could help in the confinement of the pathologies related to lipid accumulation. In this study the LDs' size distribution, number and the total volume of immature (n=12), mature (n=12, 10-days differentiated) and lipolytic (n=12) 3T3-L1 adipocytes were considered. More than 11,000 LDs were measured in the 36 cells after Oil Red O staining. In a previous work Monte Carlo simulations were used to mimic the fusion process alone between LDs. We found that, considering the fusion as the only process acting on the LDs, the size distribution in mature adipocytes can be obtained with numerical simulation starting from the size distribution in immature cells provided a very high rate of fusion events. In this paper Monte Carlo simulations were developed to mimic the interaction between LDs taking into account many other processes in addition to fusion (de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets) in order to reproduce the LDs growth and we also simulated the

  3. Models of lipid droplets growth and fission in adipocyte cells

    Energy Technology Data Exchange (ETDEWEB)

    Boschi, Federico, E-mail: federico.boschi@univr.it [Department of Computer Science, University of Verona, Strada Le Grazie 15, 37134 Verona (Italy); Rizzatti, Vanni; Zamboni, Mauro [Department of Medicine, Geriatric Section, University of Verona, Piazzale Stefani 1, 37126 Verona (Italy); Sbarbati, Andrea [Department of Neurological and Movement Sciences, University of Verona, Strada Le Grazie 8, 37134 Verona (Italy)

    2015-08-15

    Lipid droplets (LD) are spherical cellular inclusion devoted to lipids storage. It is well known that excessive accumulation of lipids leads to several human worldwide diseases like obesity, type 2 diabetes, hepatic steatosis and atherosclerosis. LDs' size range from fraction to one hundred of micrometers in adipocytes and is related to the lipid content, but their growth is still a puzzling question. It has been suggested that LDs can grow in size due to the fusion process by which a larger LD is obtained by the merging of two smaller LDs, but these events seems to be rare and difficult to be observed. Many other processes are thought to be involved in the number and growth of LDs, like the de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets. Moreover the number and size of LDs are influenced by the catabolism and the absorption or interaction with other organelles. The comprehension of these processes could help in the confinement of the pathologies related to lipid accumulation. In this study the LDs' size distribution, number and the total volume of immature (n=12), mature (n=12, 10-days differentiated) and lipolytic (n=12) 3T3-L1 adipocytes were considered. More than 11,000 LDs were measured in the 36 cells after Oil Red O staining. In a previous work Monte Carlo simulations were used to mimic the fusion process alone between LDs. We found that, considering the fusion as the only process acting on the LDs, the size distribution in mature adipocytes can be obtained with numerical simulation starting from the size distribution in immature cells provided a very high rate of fusion events. In this paper Monte Carlo simulations were developed to mimic the interaction between LDs taking into account many other processes in addition to fusion (de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets) in order to reproduce the LDs growth and we also simulated the

  4. The adipokine Chemerin induces lipolysis and adipogenesis in bovine intramuscular adipocytes.

    Science.gov (United States)

    Fu, Yuan-Yuan; Chen, Kun-Lin; Li, Hui-Xia; Zhou, Guang-Hong

    2016-07-01

    The adipokine Chemerin is reported to regulate adipogenesis and glucose homeostasis in vivo and in 3T3-L1 cells. Our team is focused on the role of Chemerin in metabolism and intramuscular adipocyte differentiation because intramuscular fat is the basic material for the formation of marbling in livestock and poultry meat. In this study, bovine intramuscular mature adipocytes were cultured in medium with Chemerin, and the process of lipolysis of mature adipocytes and the adipogenesis of de-differentiated preadipocytes were investigated. The results showed that Chemerin induced significant lipolytic metabolism in intramuscular mature adipocytes, indicated by increased levels of glycerol, FFA, and up-regulated expression of the lipolysis critical factors HSL, LPL, and leptin. Meanwhile, the expressions of adipogenic key factors PPARγ, C/EBPα, and A-FABP were decreased by Chemerin during lipolysis or dedifferentiation in mature adipocytes. The de-differentiated preadipocytes could re-differentiate into mature adipocytes. Intriguingly, the formation of cells' lipid droplets was promoted by Chemerin during preadipocyte differentiation. In addition, mRNA and protein expressions of PPARγ, C/EBPα, and A-FABP were up-regulated by Chemerin during preadipocytes differentiation. These results suggest that Chemerin promotes lipolysis in mature adipocytes and induces adipogenesis during preadipocyte re-differentiation, further indicating a dual role for Chemerin in the deposition of intramuscular fat in ruminant animals.

  5. Exposure to Tumescent Solution Significantly Increases Phosphorylation of Perilipin in Adipocytes.

    Science.gov (United States)

    Keskin, Ilknur; Sutcu, Mustafa; Eren, Hilal; Keskin, Mustafa

    2017-02-01

    Lidocaine and epinephrine could potentially decrease adipocyte viability, but these effects have not been substantiated. The phosphorylation status of perilipin in adipocytes may be predictive of cell viability. Perilipin coats lipid droplets and restricts access of lipases; phospho-perilipin lacks this protective function. The authors investigated the effects of tumescent solution containing lidocaine and epinephrine on the phosphorylation status of perilipin in adipocytes. In this in vitro study, lipoaspirates were collected before and after tumescence from 15 women who underwent abdominoplasty. Fat samples were fixed, sectioned, and stained for histologic and immunohistochemical analyses. Relative phosphorylation of perilipin was inferred from pixel intensities of immunostained adipocytes observed with confocal microscopy. For adipocytes collected before tumescent infiltration, 10.08% of total perilipin was phosphorylated. In contrast, 30.62% of total perilipin was phosphorylated for adipocytes collected from tumescent tissue (P < .01). The tumescent technique increases the relative phosphorylation of perilipin in adipocytes, making these cells more vulnerable to lipolysis. Tumescent solution applied for analgesia or hemostasis of the donor site should contain the lowest possible concentrations of lidocaine and epinephrine. LEVEL OF EVIDENCE 5. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  6. TBTC induces adipocyte differentiation in human bone marrow long term culture

    International Nuclear Information System (INIS)

    Carfi, M.; Croera, C.; Ferrario, D.; Campi, V.; Bowe, G.; Pieters, R.; Gribaldo, L.

    2008-01-01

    Organotins are widely used in agriculture and the chemical industry, causing persistent and widespread pollution. Organotins may affect the brain, liver and immune system and eventually human health. Recently, it has been shown that tri-butyltin (TBT) interacts with nuclear receptors PPARγ (peroxisome proliferator-activated receptor γ) and RXR (retinoid x receptor) leading to adipocyte differentiation in the 3T3 cell line. Since adipocytes are known to influence haematopoiesis, for instance through the expression of cytokines and adhesion molecules, it was considered of interest to further study the adipocyte-stimulating effect of TBTC in human bone marrow cultures. Nile Red spectrofluorimetric analysis showed a significant increase of adipocytes in TBTC-treated cultures after 14 days of long term culture. Real-time PCR and Western blot analysis confirmed the high expression of the specific adipocyte differentiation marker aP2 (adipocyte-specific fatty acid binding protein). PPARγ, but not RXR, mRNA was increased after 24 h and 48 h exposure. TBTC also induced a decrease in a number of chemokines, interleukins, and growth factors. Also the expression of leptin, a hormone involved in haematopoiesis, was down regulated by TBTC treatment. It therefore appears that TBTC induced adipocyte differentiation, whilst reducing a number of haematopoietic factors. This study indicates that TBTC may interfere in the haematopoietic process through an alteration of the stromal layer and cytokine homeostasis

  7. Human Adipocytes Induce Inflammation and Atrophy in Muscle Cells During Obesity.

    Science.gov (United States)

    Pellegrinelli, Vanessa; Rouault, Christine; Rodriguez-Cuenca, Sergio; Albert, Victorine; Edom-Vovard, Frédérique; Vidal-Puig, Antonio; Clément, Karine; Butler-Browne, Gillian S; Lacasa, Danièle

    2015-09-01

    Inflammation and lipid accumulation are hallmarks of muscular pathologies resulting from metabolic diseases such as obesity and type 2 diabetes. During obesity, the hypertrophy of visceral adipose tissue (VAT) contributes to muscle dysfunction, particularly through the dysregulated production of adipokines. We have investigated the cross talk between human adipocytes and skeletal muscle cells to identify mechanisms linking adiposity and muscular dysfunctions. First, we demonstrated that the secretome of obese adipocytes decreased the expression of contractile proteins in myotubes, consequently inducing atrophy. Using a three-dimensional coculture of human myotubes and VAT adipocytes, we showed the decreased expression of genes corresponding to skeletal muscle contractility complex and myogenesis. We demonstrated an increased secretion by cocultured cells of cytokines and chemokines with interleukin (IL)-6 and IL-1β as key contributors. Moreover, we gathered evidence showing that obese subcutaneous adipocytes were less potent than VAT adipocytes in inducing these myotube dysfunctions. Interestingly, the atrophy induced by visceral adipocytes was corrected by IGF-II/insulin growth factor binding protein-5. Finally, we observed that the skeletal muscle of obese mice displayed decreased expression of muscular markers in correlation with VAT hypertrophy and abnormal distribution of the muscle fiber size. In summary, we show the negative impact of obese adipocytes on muscle phenotype, which could contribute to muscle wasting associated with metabolic disorders. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  8. Relationship of adipocyte size to hyperphagia in developing male obese Zucker rats.

    Science.gov (United States)

    Vasselli, J R; Fiene, J A; Maggio, C A

    1992-01-01

    In growing male obese Zucker rats, hyperphagia reaches a maximum or "breakpoint" and declines at an earlier age with high fat than with chow-type diets. A serial adipose tissue biopsy technique was used to correlate changes of retroperitoneal adipocyte size and feeding behavior in 5- to 7-wk-old male lean and obese rats fed laboratory chow or a 35% fat diet until 30 wk of age. Although chow-fed groups had significantly greater cumulative intake, fat-fed groups had significantly greater body weight gain, retroperitoneal depot weight, and adipocyte number. Mean adipocyte size increased continuously in chow-fed groups but decreased over weeks 20-30 in fat-fed groups, reflecting increased adipocyte number. In fat-fed obese rats, hyperphagia reached a breakpoint at 11 wk and disappeared by 13 wk. In chow-fed obese rats, hyperphagia reached a breakpoint at 15-16 wk and disappeared by 19 wk. Biopsy samples revealed that adipocyte size of fat-fed obese rats was already close to maximal at 10 wk (1.12 micrograms lipid), while that of chow-fed obese rats only approached maximal at 20 wk (0.81 microgram lipid). At these time points, lipoprotein lipase activity paralleled adipocyte size. These data indicate that the duration of the growing obese rat's hyperphagia coincides with adipocyte filling and suggest the existence of feeding stimulatory and inhibitory signals from adipose tissue.

  9. Adipocyte size and cellular expression of caveolar proteins analyzed by confocal microscopy

    DEFF Research Database (Denmark)

    Hulstrøm, Veronica; Prats Gavalda, Clara; Vinten, Jørgen

    2013-01-01

    Caveolae are abundant in adipocytes and are involved in the regulation of lipid accumulation, which is the main volume determinant of these cells. We have developed and applied a confocal microscopic technique for measuring individual cellular expression of the caveolar proteins cavin-1 and caveo......Caveolae are abundant in adipocytes and are involved in the regulation of lipid accumulation, which is the main volume determinant of these cells. We have developed and applied a confocal microscopic technique for measuring individual cellular expression of the caveolar proteins cavin-1...... and caveolin-1 along with the size of individual adipocytes. The technique was applied on collagenase isolated adipocytes from ad libitum fed Sprague-Dawley rats of different age (4-26 wk) and weight (103-629 g). We found that cellular expression of caveolar proteins was variable (SD of log expression...... in the range from 0.25 to 0.65). Regression analysis of protein expression on adipocyte size revealed that the expression of the caveolar proteins cavin-1 and caveolin-1 on adipocytes from individual rats was tightly related to adipocyte cell surface area (mean coefficient of regression was 0.83 for cavin...

  10. Adipocytes from New Zealand Obese Mice Exhibit Aberrant Proinflammatory Reactivity to the Stress Signal Heat Shock Protein 60

    Directory of Open Access Journals (Sweden)

    Tina Märker

    2014-01-01

    Full Text Available Adipocytes release immune mediators that contribute to diabetes-associated inflammatory processes. As the stress protein heat shock protein 60 (Hsp60 induces proinflammatory adipocyte activities, we hypothesized that adipocytes of diabetes-predisposed mice exhibit an increased proinflammatory reactivity to Hsp60. Preadipocytes and mature adipocytes from nonobese diabetic (NOD, New Zealand obese (NZO, and C57BL/6J mice were analyzed for Hsp60 binding, Hsp60-activated signaling pathways, and Hsp60-induced release of the chemokine CXCL-1 (KC, interleukin 6 (IL-6, and macrophage chemoattractant protein-1 (MCP-1. Hsp60 showed specific binding to (pre-adipocytes of NOD, NZO, and C57BL/6J mice. Hsp60 binding involved conserved binding structure(s and Hsp60 epitopes and was strongest to NZO mouse-derived mature adipocytes. Hsp60 exposure induced KC, IL-6, and MCP-1 release from (pre-adipocytes of all mouse strains with a pronounced increase of IL-6 release from NZO mouse-derived adipocytes. Compared to NOD and C57BL/6J mouse derived cells, Hsp60-induced formation of IL-6, KC, and MCP-1 from NZO mouse-derived (pre-adipocytes strongly depended on NFκB-activation. Increased Hsp60 binding and Hsp60-induced IL-6 release by mature adipocytes of NZO mice suggest that enhanced adipocyte reactivity to the stress signal Hsp60 contributes to inflammatory processes underlying diabetes associated with obesity and insulin resistance.

  11. Transgenic overexpression of protein targeting to glycogen markedly increases adipocytic glycogen storage in mice.

    Science.gov (United States)

    Jurczak, Michael J; Danos, Arpad M; Rehrmann, Victoria R; Allison, Margaret B; Greenberg, Cynthia C; Brady, Matthew J

    2007-03-01

    Adipocytes express the rate-limiting enzymes required for glycogen metabolism and increase glycogen synthesis in response to insulin. However, the physiological function of adipocytic glycogen in vivo is unclear, due in part to the low absolute levels and the apparent biophysical constraints of adipocyte morphology on glycogen accumulation. To further study the regulation of glycogen metabolism in adipose tissue, transgenic mice were generated that overexpressed the protein phosphatase-1 (PP1) glycogen-targeting subunit (PTG) driven by the adipocyte fatty acid binding protein (aP2) promoter. Exogenous PTG was detected in gonadal, perirenal, and brown fat depots, but it was not detected in any other tissue examined. PTG overexpression resulted in a modest redistribution of PP1 to glycogen particles, corresponding to a threefold increase in the glycogen synthase activity ratio. Glycogen synthase protein levels were also increased twofold, resulting in a combined greater than sixfold enhancement of basal glycogen synthase specific activity. Adipocytic glycogen levels were increased 200- to 400-fold in transgenic animals, and this increase was maintained to 1 yr of age. In contrast, lipid metabolism in transgenic adipose tissue was not significantly altered, as assessed by lipogenic rates, weight gain on normal or high-fat diets, or circulating free fatty acid levels after a fast. However, circulating and adipocytic leptin levels were doubled in transgenic animals, whereas adiponectin expression was unchanged. Cumulatively, these data indicate that murine adipocytes are capable of storing far higher levels of glycogen than previously reported. Furthermore, these results were obtained by overexpression of an endogenous adipocytic protein, suggesting that mechanisms may exist in vivo to maintain adipocytic glycogen storage at a physiological set point.

  12. The Effect of Growth Hormone on Lipid Accumulation or Maturation in Adipocytes

    Directory of Open Access Journals (Sweden)

    Yuchao Zhang

    2016-11-01

    Full Text Available Background: Adipogenesis of adipocytes includes two stages: initiation and maturation. Growth hormone (GH secretion is decreased in obese subjects and GH levels are inversely correlated with abdominal fat mass. The effects of growth hormone (GH on lipids accumulation or maturation of adipocytes remains elusive. Methods: In the present study, effect of GH on lipid accumulation in vitro and in vivo was examined. cDNA microarray, quantitative real time-PCR (qPCR and western blotting was used to analyze the expression of genes related to adipocyte lipid accumulation or degradation in pre- or mature 3T3-F442A adipocytes treated with GH and in epididymal adipose tissue of C57BL/6 mice administrated with GH. Level of adiponectin in supernatants of cultured F442A adipocytes was determined by enzyme-linked immune-sorbent assay. Results: We found that in 3T3-F442A especially 6 days post initiation of adipogenesis, GH intervention resulted in decreased expression of adipocyte maturation regulators (C/EBPα, PPARγ and prominent genes related to lipid synthesis such as FAS and FABP, while the expression of UCP1 was markedly enhanced. cDNA microarray analysis and qPCR showed that the expression of SOCS2 and Adipor2 was increased under GH-treatment in mature 3T3-F442A adipocytes. GH treatment increased the mRNA expression of adiponectin and UCP1 in mature adipocytes. The above results were confirmed by in vivo study. Conclusions: GH potentially negatively modulates the maturation and accumulation of lipid in adipocytes.

  13. Quantitative changes in adipocyte plasma membrane in response to nutritional manipulations

    International Nuclear Information System (INIS)

    Lewis, D.S.; Masoro, E.J.; Yu, B.P.

    1981-01-01

    The effects of changes in adipocyte size and the effects of nutritional manipulations on the quantity of plasma membrane per adipocyte were investigated. A method for estimating the quantity of plasma membrane was developed based on the specific labeling of adipocyte plasma membrane protein with the nonpermeable labeling agent 125I-labeled diazotized diiodosulfanilic acid. By studying rats (ranging in age from 50 to 125 days) fed a standard laboratory chow or a low fat diet or a high fat diet, a wide range of mean fat cell sizes was obtained. It was found that as the volume of the fat cell increased, the amount of plasma membrane increased in a linear fashion and that this linear relationship had the same slope whether the size of the adipocyte increased slowly with age or rapidly in response to a high fat diet. In contrast, fasting for up to 3 days caused a marked decrease in the mean volume of the adipocytes, but either no change or much less change in the amount of plasma membrane per cell than would have been predicted from the linear relationship between adipocytes, but either no change or much less change in the amount of plasma membrane per cell than would have been predicted form the linear relationship between adipocyte volume and amount of plasma membrane per cell obtained with fed rats, i.e., adipocytes from fasted rats contain more plasma membrane per cell than do fat cells of the same size from fed rats. Neither feeding a high fat diet nor fasting caused detectable changes in the protein and lipid composition of the adipocyte plasma membrane

  14. Differential effects of pertussis toxin on insulin-stimulated phosphatidylcholine hydrolysis and glycerolipid synthesis de novo. Studies in BC3H-1 myocytes and rat adipocytes

    International Nuclear Information System (INIS)

    Hoffman, J.M.; Standaert, M.L.; Nair, G.P.; Farese, R.V.

    1991-01-01

    Insulin-induced increases in diacylglycerol (DAG) have been suggested to result from stimulation of de novo phosphatidic acid (PA) synthesis and phosphatidylcholine (PC) hydrolysis. Presently, the authors found that insulin decreased PC levels of BC3H-1 myocytes and rat adipocytes by approximately 10-25% within 30 s. These decreases were rapidly reversed in both cell types, apparently because of increased PC synthesis de novo. In BC3H-1 myocytes, pertussis toxin inhibited PC resynthesis and insulin effects on the pathway of de novo PA-DAG-PC synthesis, as evidenced by changes in [ 3 H]glycerol incorporation, but did not inhibit insulin-stimulated PC hydrolysis. Pertussis toxin also blocked the later, but not the initial, increase in DAG production in the myocytes. Phorbol esters activated PC hydrolysis in both myocytes and adipocytes, but insulin-induced stimulation of PC hydrolysis was not dependent upon activation of PKC, since this hydrolysis was not inhibited by 500 μM sangivamycin, an effective PKC inhibitor. The results indicate that insulin increases DAG by pertussis toxin sensitive and insensitive (PC hydrolysis) mechanisms, which are mechanistically separate, but functionally interdependent and integrated. PC hydrolysis may contribute importantly to initial increases in DAG, but later sustained increases are apparently largely dependent on insulin-induced stimulation of the pathway of de novo phospholipid synthesis

  15. Differential effects of pertussis toxin on insulin-stimulated phosphatidylcholine hydrolysis and glycerolipid synthesis de novo. Studies in BC3H-1 myocytes and rat adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, J.M.; Standaert, M.L.; Nair, G.P.; Farese, R.V. (Univ. of South Florida, Tampa (USA))

    1991-04-02

    Insulin-induced increases in diacylglycerol (DAG) have been suggested to result from stimulation of de novo phosphatidic acid (PA) synthesis and phosphatidylcholine (PC) hydrolysis. Presently, the authors found that insulin decreased PC levels of BC3H-1 myocytes and rat adipocytes by approximately 10-25% within 30 s. These decreases were rapidly reversed in both cell types, apparently because of increased PC synthesis de novo. In BC3H-1 myocytes, pertussis toxin inhibited PC resynthesis and insulin effects on the pathway of de novo PA-DAG-PC synthesis, as evidenced by changes in ({sup 3}H)glycerol incorporation, but did not inhibit insulin-stimulated PC hydrolysis. Pertussis toxin also blocked the later, but not the initial, increase in DAG production in the myocytes. Phorbol esters activated PC hydrolysis in both myocytes and adipocytes, but insulin-induced stimulation of PC hydrolysis was not dependent upon activation of PKC, since this hydrolysis was not inhibited by 500 {mu}M sangivamycin, an effective PKC inhibitor. The results indicate that insulin increases DAG by pertussis toxin sensitive and insensitive (PC hydrolysis) mechanisms, which are mechanistically separate, but functionally interdependent and integrated. PC hydrolysis may contribute importantly to initial increases in DAG, but later sustained increases are apparently largely dependent on insulin-induced stimulation of the pathway of de novo phospholipid synthesis.

  16. Chronic peroxisome proliferator-activated receptor gamma (PPARgamma) activation of epididymally derived white adipocyte cultures reveals a population of thermogenically competent, UCP1-containing adipocytes molecularly distinct from classic brown adipocytes

    DEFF Research Database (Denmark)

    Petrovic, Natasa; Walden, Tomas B; Shabalina, Irina G

    2009-01-01

    The recent insight that brown adipocytes and muscle cells share a common origin and in this respect are distinct from white adipocytes has spurred questions concerning the origin and molecular characteristics of the UCP1-expressing cells observed in classic white adipose tissue depots under certain...... physiological or pharmacological conditions. Examining precursors from the purest white adipose tissue depot (epididymal), we report here that chronic treatment with the peroxisome proliferator-activated receptor gamma agonist rosiglitazone promotes not only the expression of PGC-1alpha and mitochondriogenesis...... associated with classic brown adipocytes (Zic1, Lhx8, Meox2, and characteristically PRDM16) or for myocyte-associated genes (myogenin and myomirs (muscle-specific microRNAs)) and retain white fat characteristics such as Hoxc9 expression. Co-culture experiments verify that the UCP1-expressing cells...

  17. Browning of human adipocytes requires KLF11 and reprogramming of PPARγ superenhancers

    DEFF Research Database (Denmark)

    Loft, Anne; Forss, Isabel; Siersbæk, Majken Storm

    2015-01-01

    Long-term exposure to peroxisome proliferator-activated receptor γ (PPARγ) agonists such as rosiglitazone induces browning of rodent and human adipocytes; however, the transcriptional mechanisms governing this phenotypic switch in adipocytes are largely unknown. Here we show that rosiglitazone...... reprogramming of PPARγ binding, leading to the formation of PPARγ "superenhancers" that are selective for brown-in-white (brite) adipocytes. These are highly associated with key brite-selective genes. Based on such an association, we identified an evolutionarily conserved metabolic regulator, Kruppel...

  18. Characterization of lipid metabolism in insulin-sensitive adipocytes differentiated from immortalized human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Prawitt, Janne; Niemeier, Andreas; Kassem, Moustapha

    2008-01-01

    There is a great demand for cell models to study human adipocyte function. Here we describe the adipogenic differentiation of a telomerase-immortalized human mesenchymal stem cell line (hMSC-Tert) that maintains numerous features of terminally differentiated adipocytes even after prolonged...... receptor (VLDLR, LRP1) and apolipoprotein E expression during differentiation. Despite this increased expression, the receptor-mediated endocytosis of lipoproteins was decreased in differentiated adipocytes, suggesting that these proteins may have an additional function in adipose tissue beyond lipoprotein...

  19. Retinoblastoma protein functions as a molecular switch determining white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; Jørgensen, Claus; Petersen, Rasmus K

    2004-01-01

    at a developmental stage where both cell types begin to accumulate lipid and brown adipocytes express UCP-1. Furthermore, pRB rapidly undergoes phosphorylation upon cold-induced neodifferentiation and up-regulation of UCP-1 expression in brown adipose tissue. Finally, down-regulation of pRB expression accompanies...... transdifferentiation of white into brown adipocytes in response to beta3-adrenergic receptor agonist treatment. We propose that pRB acts as a molecular switch determining white vs. brown adipogenesis, suggesting a previously uncharacterized function of this key cell cycle regulator in adipocyte lineage commitment...

  20. The Therapeutic Potential of Brown Adipocytes in Humans

    Directory of Open Access Journals (Sweden)

    Craig ePorter

    2015-10-01

    Full Text Available Obesity and its metabolic consequences represent a significant clinical problem. From a thermodynamic standpoint, obesity results from a discord in energy intake and expenditure. To date, lifestyle interventions based on reducing energy intake and/or increasing energy expenditure have proved ineffective in the prevention and treatment of obesity, owing to poor long-term adherence to such interventions. Thus, an effective strategy to prevent or correct obesity is currently lacking.As the combustion engines of our cells, mitochondria play a critical role in energy expenditure. At a whole body level, approximately 80% of mitochondrial membrane potential generated by fuel oxidation is used to produce ATP, and the remaining 20% is lost through heat-producing uncoupling reactions. The coupling of mitochondrial respiration to ATP production represents an important component in whole body energy expenditure. Brown adipose tissue (BAT is densely populated with mitochondria containing the inner mitochondrial proton carrier uncoupling protein 1 (UCP. UCP1 uncouples oxidative phosphorylation, meaning that mitochondrial membrane potential is dissipated as heat. The recent re-discovery of BAT depots in adult humans has rekindled scientific interest in the manipulation of mitochondrial uncoupling reactions as a means to increase metabolic rate, thereby counteracting obesity and its associated metabolic phenotype. In this article, we discuss the evidence for the role BAT plays in metabolic rate and glucose and lipid metabolism in humans, and the potential for UCP1 recruitment in the white adipose tissue of humans. While the future holds much promise for a therapeutic role of UCP1 expressing adipocytes in human energy metabolism, particularly in the context of obesity, tissue specific strategies that activate or recruit UCP1 in human adipocytes represent an obligatory translation step for this early promise to be realized.

  1. Topiramate effects lipolysis in 3T3-L1 adipocytes.

    Science.gov (United States)

    Martins, Gabriela Poltronieri Campagnaro; Souza, Camila Oliveira; Marques, Scherolin; Luciano, Thais Fernandes; DA Silva Pieri, Bruno Luiz; Rosa, José César; DA Silva, Adelino Sanchez Ramos; Pauli, José Rodrigo; Cintra, Dennys Esper; Ropelle, Eduardo Rochete; Rodrigues, Bruno; DE Lira, Fabio Santos; DE Souza, Claudio Teodoro

    2015-11-01

    Studies have shown that topiramate (TPM)-induced weight loss can be dependent on the central nervous system (CNS). However, the direct action of TPM on adipose tissue has not been tested previously. Thus, the present study aimed to examine whether TPM modulates lipolysis in 3T3-L1. The 3T3-L1 cells were incubated in 50 µM TPM for 30 min. The β-adrenergic stimulator, isoproterenol, was used as a positive control. The release of lactate dehydrogenase, non-esterified fatty acid, glycerol and incorporation of 14 C-palmitate to lipid were analyzed. The phosphorylation of protein kinase A (PKA), hormone-sensitive lipase (HSL), adipocyte triglyceride lipase (ATGL) and perilipin A, as well as the protein levels of comparative genetic identification 58 (CGI-58) were assessed. The levels of glycerol and non-esterified fatty acid increased markedly when the cells were treated with TPM. The TPM effects were similar to the isoproterenol positive control. Additionally, TPM reduced lipogenesis. These results were observed without any change in cell viability. Finally, the phosphorylation of PKA, HSL, ATGL and perilipin A, as well as the protein levels of CGI-58 were increased compared to the control cells. These results were similar to those observed in the cells treated with isoproterenol. The present results show that TPM increased the phosphorylation of pivotal lipolytic enzymes, which induced lipolysis in 3T3-L1 adipocytes, suggesting that this drug may act directly in the adipose tissue independent from its effect on the CNS.

  2. How do in-vitro release profiles of nanosuspensions from Alzet® pumps correspond to the in-vivo situation? A case study on radiolabeled fenofibrate.

    Science.gov (United States)

    Hill, A; Breyer, S; Geissler, S; Mier, W; Haberkorn, U; Weigandt, M; Mäder, K

    2013-05-28

    In research and development sufficiently high and constant plasma levels of drug candidates are often requested, but simple solutions of hydrophobic drugs delivered from the commonly used micro-osmotic pumps cannot meet these demands. Nanosuspensions released from implanted osmotic devices can be a strategy to overcome this challenge but little is known about their pharmacokinetic behavior after subcutaneous application. In the current study, four different nanosuspension formulations containing iodinated fenofibrate were prepared, physicochemically characterized and investigated concerning their in-vitro release kinetics from osmotic pumps. One nanosuspension of lower viscosity exhibited thereby an unexpectedly first order release kinetics, whereas the higher viscous counterpart was released in the expected zero-order manner. To assess the relation of the in-vitro release kinetics to the in-vivo fate of nanosuspensions, various [(131)I] iodinated fenofibrate formulations were subcutaneously applied to mice. The biodistribution was followed by means of γ-scintigraphy and γ-scintillation. Two different nanosuspensions released from osmotic pumps were compared to bolus injections of a nanosuspension and an organic drug solution. The distribution and elimination of the bolus injected drug solution were almost completed within 48h. In contrast, a long lasting (>1week) depot at the injection site was formed by the bolus injected nanosuspension. Ex vivo examination of the organs showed a sustained, but exponential decrease of the radiolabel concentration. More constant drug levels in the organs were achieved within the nanosuspensions released from osmotic pumps. The organ levels of [(131)I] labeled fenofibrate were found to be more constant in case of the pump with the higher viscous nanosuspension in contrast to the lower viscous counterpart. However, the very different release profiles of the lower and higher viscous nanosuspension observed in-vitro were not

  3. Effect of physical training on glucose transporter protein and mRNA levels in rat adipocytes

    DEFF Research Database (Denmark)

    Stallknecht, B; Andersen, P H; Vinten, J

    1993-01-01

    Physical training increases insulin-stimulated glucose transport and the number of glucose transporters in adipocytes measured by cytochalasin B binding. In the present study we used immunoblotting to measure the abundance of two glucose transporters (GLUT-4, GLUT-1) in white adipocytes from...... trained rats. Furthermore, the abundance of the mRNAs for these proteins and glucose transport was measured. Rats were swim-trained for 10 wk, and adipocytes were isolated from epididymal fat pads. The amount of GLUT-4/adipocyte volume unit was significantly higher in trained animals compared with both...... age- and cell size-matched animals. The amount of GLUT-4 mRNA was also increased by training and it decreased with increasing age. Furthermore, young age as well as training was accompanied by relatively low GLUT-4 protein/mRNA and relatively high overall GLUT-4 efficiency (recruitability and...

  4. Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

    2004-01-01

    The differentiation of white and brown fat cells is controlled by a similar set of transcription factors, including PPARgamma and C/EBPalpha. However, despite many similarities between the two types of fat cells, they carry out essentially opposite functions in vivo, with white adipocytes being...... the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation...... in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation....

  5. microRNA-320/RUNX2 axis regulates adipocytic differentiation of human mesenchymal (skeletal) stem cells

    DEFF Research Database (Denmark)

    Hamam, D; Ali, D; Vishnubalaji, R

    2014-01-01

    The molecular mechanisms promoting lineage-specific commitment of human mesenchymal (skeletal or stromal) stem cells (hMSCs) into adipocytes (ADs) are not fully understood. Thus, we performed global microRNA (miRNA) and gene expression profiling during adipocytic differentiation of h......MSC, and utilized bioinformatics as well as functional and biochemical assays, and identified several novel miRNAs differentially expressed during adipogenesis. Among these, miR-320 family (miR-320a, 320b, 320c, 320d and 320e) were ~2.2-3.0-fold upregulated. Overexpression of miR-320c in hMSC enhanced adipocytic...... differentiation and accelerated formation of mature ADs in ex vivo cultures. Integrated analysis of bioinformatics and global gene expression profiling in miR-320c overexpressing cells and during adipocytic differentiation of hMSC identified several biologically relevant gene targets for miR-320c including RUNX2...

  6. Regulation of AMP-activated protein kinase by LKB1 and CaMKK in adipocytes

    DEFF Research Database (Denmark)

    Gormand, Amélie; Henriksson, Emma; Ström, Kristoffer

    2011-01-01

    AMP-activated protein kinase (AMPK) is a serine/threonine kinase that regulates cellular and whole body energy homeostasis. In adipose tissue, activation of AMPK has been demonstrated in response to a variety of extracellular stimuli. However, the upstream kinase that activates AMPK in adipocytes...... remains elusive. Previous studies have identified LKB1 as a major AMPK kinase in muscle, liver, and other tissues. In certain cell types, Ca(2+) /calmodulin-dependent protein kinase kinase β (CaMKKβ) has been shown to activate AMPK in response to increases of intracellular Ca(2+) levels. Our aim...... was to investigate if LKB1 and/or CaMKK function as AMPK kinases in adipocytes. We used adipose tissue and isolated adipocytes from mice in which the expression of LKB1 was reduced to 10-20% of that of wild-type (LKB1 hypomorphic mice). We show that adipocytes from LKB1 hypomorphic mice display a 40% decrease...

  7. Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

    2004-01-01

    the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation...... of adipocyte differentiation, and expression and phosphorylation of the three retinoblastoma family proteins oscillate in a characteristic manner during differentiation of the white preadipocyte cell line 3T3-L1. We have recently demonstrated a surprising function of the retinoblastoma protein...... in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation....

  8. Deficiency of the GPR39 receptor is associated with obesity and altered adipocyte metabolism

    DEFF Research Database (Denmark)

    Petersen, Pia Steen; Jin, Chunyu; Madsen, Andreas Nygaard

    2011-01-01

    on body weight and adipocyte metabolism. GPR39-deficient mice were subjected to a high-fat diet and body composition, glucose tolerance, insulin secretion, food intake, and energy expenditure were evaluated. The cell biology of adipocyte metabolism was studied on both mRNA and protein levels......-induced thermogenesis, measured by the oxygen consumption rate (Vo(2)) on change from normal to high-fat diet. Analysis of the adipose tissue for lipolytic enzymes demonstrated decreased level of phosphorylated hormone-sensitive lipase (HSL) and a decreased level of adipose triglyceride lipase (ATGL) by 35 and 60......, conceivably due to decreased energy expenditure and adipocyte lipolytic activity.-Petersen, P. S., Jin, C., Madsen, A. N., Rasmussen, M., Kuhre, R., L. Egerod, K. L., Nielsen, L. B., Schwartz. T. W., Holst, B. Deficiency of the GPR39 receptor is associated with obesity and altered adipocyte metabolism....

  9. Overexpressing cell systems are a competitive option to primary adipocytes when predicting in vivo potency of dual GPR81/GPR109A agonists.

    Science.gov (United States)

    Almquist, Joachim; Hovdal, Daniel; Ahlström, Christine; Fjellström, Ola; Gennemark, Peter; Sundqvist, Monika

    2018-03-01

    Mathematical models predicting in vivo pharmacodynamic effects from in vitro data can accelerate drug discovery, and reduce costs and animal use. However, data integration and modeling is non-trivial when more than one drug-target receptor is involved in the biological response. We modeled the inhibition of non-esterified fatty acid release by dual G-protein-coupled receptor 81/109A (GPR81/GPR109A) agonists in vivo in the rat, to estimate the in vivo EC 50 values for 12 different compounds. We subsequently predicted those potency estimates using EC 50 values obtained from concentration-response data in isolated primary adipocytes and cell systems overexpressing GPR81 or GPR109A in vitro. A simple linear regression model based on data from primary adipocytes predicted the in vivo EC 50 better than simple linear regression models based on in vitro data from either of the cell systems. Three models combining the data from the overexpressing cell systems were also evaluated: two piecewise linear models defining logical OR- and AND-circuits, and a multivariate linear regression model. All three models performed better than the simple linear regression model based on data from primary adipocytes. The OR-model was favored since it is likely that activation of either GPR81 or GPR109A is sufficient to deactivate the cAMP pathway, and thereby inhibit non-esterified fatty acid release. The OR-model was also able to predict the in vivo selectivity between the two receptors. Finally, the OR-model was used to predict the in vivo potency of 1651 new compounds. This work suggests that data from the overexpressing cell systems are sufficient to predict in vivo potency of GPR81/GPR109A agonists, an approach contributing to faster and leaner drug discovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Adipocyte Metabolic Pathways Regulated by Diet Control the Female Germline Stem Cell Lineage inDrosophila melanogaster.

    Science.gov (United States)

    Matsuoka, Shinya; Armstrong, Alissa R; Sampson, Leesa L; Laws, Kaitlin M; Drummond-Barbosa, Daniela

    2017-06-01

    Nutrients affect adult stem cells through complex mechanisms involving multiple organs. Adipocytes are highly sensitive to diet and have key metabolic roles, and obesity increases the risk for many cancers. How diet-regulated adipocyte metabolic pathways influence normal stem cell lineages, however, remains unclear. Drosophila melanogaster has highly conserved adipocyte metabolism and a well-characterized female germline stem cell (GSC) lineage response to diet. Here, we conducted an isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis to identify diet-regulated adipocyte metabolic pathways that control the female GSC lineage. On a rich (relative to poor) diet, adipocyte Hexokinase-C and metabolic enzymes involved in pyruvate/acetyl-CoA production are upregulated, promoting a shift of glucose metabolism toward macromolecule biosynthesis. Adipocyte-specific knockdown shows that these enzymes support early GSC progeny survival. Further, enzymes catalyzing fatty acid oxidation and phosphatidylethanolamine synthesis in adipocytes promote GSC maintenance, whereas lipid and iron transport from adipocytes controls vitellogenesis and GSC number, respectively. These results show a functional relationship between specific metabolic pathways in adipocytes and distinct processes in the GSC lineage, suggesting the adipocyte metabolism-stem cell link as an important area of investigation in other stem cell systems. Copyright © 2017 by the Genetics Society of America.

  11. Human adipocytes are highly sensitive to intermittent hypoxia induced NF-kappaB activity and subsequent inflammatory gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Cormac T. [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Kent, Brian D.; Crinion, Sophie J.; McNicholas, Walter T. [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Pulmonary and Sleep Disorders Unit, St. Vincent’s University Hospital, Dublin (Ireland); Ryan, Silke, E-mail: silke.ryan@ucd.ie [School of Medicine and Medical Science, The Conway Institute, University College Dublin (Ireland); Pulmonary and Sleep Disorders Unit, St. Vincent’s University Hospital, Dublin (Ireland)

    2014-05-16

    Highlights: • Intermittent hypoxia (IH) leads to NF-κB activation in human primary adipocytes. • Adipocytes bear higher pro-inflammatory potential than other human primary cells. • IH leads to upregulation of multiple pro-inflammatory genes in human adipocytes. - Abstract: Introduction: Intermittent hypoxia (IH)-induced activation of pro-inflammatory pathways is a major contributing factor to the cardiovascular pathophysiology associated with obstructive sleep apnea (OSA). Obesity is commonly associated with OSA although it remains unknown whether adipose tissue is a major source of inflammatory mediators in response to IH. The aim of this study was to test the hypothesis that IH leads to augmented inflammatory responses in human adipocytes when compared to cells of non-adipocyte lineages. Methods and results: Human primary subcutaneous and visceral adipocytes, human primary microvascular pulmonary endothelial cells (HUMEC-L) and human primary small airway epithelial cells (SAEC) were exposed to 0, 6 or 12 cycles of IH or stimulated with tumor necrosis factor (TNF)-α. IH led to a robust increase in NF-κB DNA-binding activity in adipocytes compared with normoxic controls regardless of whether the source of adipocytes was visceral or subcutaneous. Notably, the NF-κB response of adipocytes to both IH and TNF-α was significantly greater than that in HUMEC-L and SAEC. Western blotting confirmed enhanced nuclear translocation of p65 in adipocytes in response to IH, accompanied by phosphorylation of I-κB. Parallel to p65 activation, we observed a significant increase in secretion of the adipokines interleukin (IL)-8, IL-6 and TNF-α with IH in adipocytes accompanied by significant upregulation of mRNA expression. PCR-array suggested profound influence of IH on pro-inflammatory gene expression in adipocytes. Conclusion: Human adipocytes demonstrate strong sensitivity to inflammatory gene expression in response to acute IH and hence, adipose tissue may be a key

  12. Human adipocytes are highly sensitive to intermittent hypoxia induced NF-kappaB activity and subsequent inflammatory gene expression

    International Nuclear Information System (INIS)

    Taylor, Cormac T.; Kent, Brian D.; Crinion, Sophie J.; McNicholas, Walter T.; Ryan, Silke

    2014-01-01

    Highlights: • Intermittent hypoxia (IH) leads to NF-κB activation in human primary adipocytes. • Adipocytes bear higher pro-inflammatory potential than other human primary cells. • IH leads to upregulation of multiple pro-inflammatory genes in human adipocytes. - Abstract: Introduction: Intermittent hypoxia (IH)-induced activation of pro-inflammatory pathways is a major contributing factor to the cardiovascular pathophysiology associated with obstructive sleep apnea (OSA). Obesity is commonly associated with OSA although it remains unknown whether adipose tissue is a major source of inflammatory mediators in response to IH. The aim of this study was to test the hypothesis that IH leads to augmented inflammatory responses in human adipocytes when compared to cells of non-adipocyte lineages. Methods and results: Human primary subcutaneous and visceral adipocytes, human primary microvascular pulmonary endothelial cells (HUMEC-L) and human primary small airway epithelial cells (SAEC) were exposed to 0, 6 or 12 cycles of IH or stimulated with tumor necrosis factor (TNF)-α. IH led to a robust increase in NF-κB DNA-binding activity in adipocytes compared with normoxic controls regardless of whether the source of adipocytes was visceral or subcutaneous. Notably, the NF-κB response of adipocytes to both IH and TNF-α was significantly greater than that in HUMEC-L and SAEC. Western blotting confirmed enhanced nuclear translocation of p65 in adipocytes in response to IH, accompanied by phosphorylation of I-κB. Parallel to p65 activation, we observed a significant increase in secretion of the adipokines interleukin (IL)-8, IL-6 and TNF-α with IH in adipocytes accompanied by significant upregulation of mRNA expression. PCR-array suggested profound influence of IH on pro-inflammatory gene expression in adipocytes. Conclusion: Human adipocytes demonstrate strong sensitivity to inflammatory gene expression in response to acute IH and hence, adipose tissue may be a key

  13. The blubber adipocyte index: A nondestructive biomarker of adiposity in humpback whales (Megaptera novaeangliae).

    Science.gov (United States)

    Castrillon, Juliana; Huston, Wilhelmina; Bengtson Nash, Susan

    2017-07-01

    The ability to accurately evaluate the energetic health of wildlife is of critical importance, particularly under conditions of environmental change. Despite the relevance of this issue, currently there are no reliable, standardized, nonlethal measures to assess the energetic reserves of large, free-roaming marine mammals such as baleen whales. This study investigated the potential of adipocyte area analysis and further, a standardized adipocyte index (AI), to yield reliable information regarding humpback whale ( Megaptera novaeangliae ) adiposity. Adipocyte area and AI, as ascertained by image analysis, showed a direct correlation with each other but only a weak correlation with the commonly used, but error prone, blubber lipid-percent measure. The relative power of the three respective measures was further evaluated by comparing humpback whale cohorts at different stages of migration and fasting. Adipocyte area, AI, and blubber lipid-percent were assessed by binary logistic regression revealing that adipocyte area had the greatest probability to predict the migration cohort with a high level of redundancy attributed to the AI given their strong linear relationship (r = -.784). When only AI and lipid-percent were assessed, the performance of both predictor variables was significant but the power of AI far exceeded lipid-percent. The sensitivity of adipocyte metrics and the rapid, nonlethal, and inexpensive nature of the methodology and AI calculation validate the inclusion of the AI in long-term monitoring of humpback whale population health, and further raises its potential for broader wildlife applications.

  14. Sympathetic transmitters control thermogenic efficacy of brown adipocytes by modulating mitochondrial complex V.

    Science.gov (United States)

    Xie, Tao-Rong; Liu, Chun-Feng; Kang, Jian-Sheng

    2017-01-01

    Obesity is a worldwide epidemic and results from excessive energy intake or inefficient energy expenditure. It is promising to utilize the thermogenic function of brown adipose tissue for obesity intervention. However, the mechanisms controlling the efficacy of norepinephrine-induced thermogenesis in brown adipocytes remain elusive. Here we demonstrate that norepinephrine (NE) induces low-efficacy thermogenesis, evoking both heterogeneous changes (ΔΨ m and ΔpH) and homogenous responses, one of which is that NE stimulation causes large amounts of ATP consumption in brown adipocytes. We reveal that the proton-ATPase activity of mitochondrial complex V is a key factor that antagonizes proton leakage by UCP1 and determines the efficacy of NE-induced thermogenesis in brown adipocytes. Furthermore, to avoid unnecessary and undesired heat production, we reveal that ATP is a necessary sympathetic cotransmitter for the high efficacy and specificity of NE-induced thermogenesis in brown adipocytes as it increases intracellular calcium concentrations and upregulates the ATP synthase activity of complex V. Thus, we demonstrate the modulation mechanism of thermogenic efficacy in brown adipocytes. These findings imply new strategies to partially or fully utilize the thermogenic capacity of brown adipocytes to identify therapeutic targets for the treatment of obesity and diabetes.

  15. Critical review of beige adipocyte thermogenic activation and contribution to whole-body energy expenditure.

    Science.gov (United States)

    Castro, Érique; Silva, Tiago E Oliveira; Festuccia, William T

    2017-09-01

    Beige (or brite, "brown in white") adipocytes are uncoupling protein 1 (UCP1)-positive cells residing in white adipose depots that, depending on the conditions, behave either as classic white adipocytes, storing energy as lipids, or as brown adipocytes, dissipating energy from oxidative metabolism as heat through non-shivering thermogenesis. Because of their thermogenic potential and, therefore, possible usage to treat metabolic diseases such as obesity and type 2 diabetes, beige cells have attracted the attention of many scientists worldwide aiming to develop strategies to safely recruit and activate their thermogenic activity. Indeed, in recent years, a large variety of conditions, molecules (including nutrients) and signaling pathways were reported to promote the recruitment of beige adipocytes. Despite of those advances, the true contribution of beige adipocyte thermogenesis to whole-body energy expenditure is still not completely defined. Herein, we discuss some important aspects that should be considered when studying beige adipocyte biology and the contribution to energy balance and whole-body metabolism.

  16. Adipocytes properties and crosstalk with immune system in obesity-related inflammation.

    Science.gov (United States)

    Maurizi, Giulia; Della Guardia, Lucio; Maurizi, Angela; Poloni, Antonella

    2018-01-01

    Obesity is a condition likely associated with several dysmetabolic conditions or worsening of cardiovascular and other chronic disturbances. A key role in this mechanism seem to be played by the onset of low-grade systemic inflammation, highlighting the importance of the interplay between adipocytes and immune system cells. Adipocytes express a complex and highly adaptive biological profile being capable to selectively activate different metabolic pathways in order to respond to environmental stimuli. It has been demonstrated how adipocytes, under appropriate stimulation, can easily differentiate and de-differentiate thereby converting themselves into different phenotypes according to metabolic necessities. Although underlying mechanisms are not fully understood, growing in adipocyte size and the inability of storing triglycerides under overfeeding conditions seem to be crucial for the switching to a dysfunctional metabolic profile, which is characterized by inflammatory and apoptotic pathways activation, and by the shifting to pro-inflammatory adipokines secretion. In obesity, changes in adipokines secretion along with adipocyte deregulation and fatty acids release into circulation contribute to maintain immune cells activation as well as their infiltration into regulatory organs. Over the well-established role of macrophages, recent findings suggest the involvement of new classes of immune cells such as T regulatory lymphocytes and neutrophils in the development inflammation and multi systemic worsening. Deeply understanding the pathways of adipocyte regulation and the de-differentiation process could be extremely useful for developing novel strategies aimed at curbing obesity-related inflammation and related metabolic disorders. © 2017 Wiley Periodicals, Inc.

  17. Oligopeptide complex for targeted non-viral gene delivery to adipocytes

    Science.gov (United States)

    Won, Young-Wook; Adhikary, Partho Protim; Lim, Kwang Suk; Kim, Hyung Jin; Kim, Jang Kyoung; Kim, Yong-Hee

    2014-12-01

    Commercial anti-obesity drugs acting in the gastrointestinal tract or the central nervous system have been shown to have limited efficacy and severe side effects. Anti-obesity drug development is thus focusing on targeting adipocytes that store excess fat. Here, we show that an adipocyte-targeting fusion-oligopeptide gene carrier consisting of an adipocyte-targeting sequence and 9-arginine (ATS-9R) selectively transfects mature adipocytes by binding to prohibitin. Injection of ATS-9R into obese mice confirmed specific binding of ATS-9R to fat vasculature, internalization and gene expression in adipocytes. We also constructed a short-hairpin RNA (shRNA) for silencing fatty-acid-binding protein 4 (shFABP4), a key lipid chaperone in fatty-acid uptake and lipid storage in adipocytes. Treatment of obese mice with ATS-9R/shFABP4 led to metabolic recovery and body-weight reduction (>20%). The ATS-9R/shFABP4 oligopeptide complex could prove to be a safe therapeutic approach to regress and treat obesity as well as obesity-induced metabolic syndromes.

  18. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    International Nuclear Information System (INIS)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A.; Yap, Sook Fan; Ngeow, Yun Fong; Chin, Khew-Voon

    2012-01-01

    Highlights: ► Salinomycin inhibits preadipocyte differentiation into adipocytes. ► Salinomycin inhibits transcriptional regulation of adipogenesis. ► Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor γ. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  19. Salinomycin, a polyether ionophoric antibiotic, inhibits adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Szkudlarek-Mikho, Maria; Saunders, Rudel A. [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States); Yap, Sook Fan [Faculty of Medicine and Health Sciences, Department of Pre-Clinical Sciences, University of Tunku Abdul Rahman (Malaysia); Ngeow, Yun Fong [Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603 (Malaysia); Chin, Khew-Voon, E-mail: khew-voon.chin@utoledo.edu [Department of Medicine, Biochemistry and Cancer Biology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH 43614 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer Salinomycin inhibits preadipocyte differentiation into adipocytes. Black-Right-Pointing-Pointer Salinomycin inhibits transcriptional regulation of adipogenesis. Black-Right-Pointing-Pointer Pharmacological effects of salinomycin suggest toxicity in cancer therapy. -- Abstract: The polyether ionophoric antibiotics including monensin, salinomycin, and narasin, are widely used in veterinary medicine and as food additives and growth promoters in animal husbandry including poultry farming. Their effects on human health, however, are not fully understood. Recent studies showed that salinomycin is a cancer stem cell inhibitor. Since poultry consumption has risen sharply in the last three decades, we asked whether the consumption of meat tainted with growth promoting antibiotics might have effects on adipose cells. We showed in this report that the ionophoric antibiotics inhibit the differentiation of preadipocytes into adipocytes. The block of differentiation is not due to the induction of apoptosis nor the inhibition of cell proliferation. In addition, salinomycin also suppresses the transcriptional activity of the CCAAT/enhancer binding proteins and the peroxisome proliferator-activated receptor {gamma}. These results suggest that the ionophoric antibiotics can be exploited as novel anti-obesity therapeutics and as pharmacological probes for the study of adipose biology. Further, the pharmacological effects of salinomycin could be a harbinger of its toxicity on the adipose tissue and other susceptible target cells in cancer therapy.

  20. Anacardium occidentale bark lectin: purification, immobilization as an affinity model and influence in the uptake of technetium-99M by rat adipocytes.

    Science.gov (United States)

    Maciel, Maria Inês Sucupira; de Mendonça Cavalcanti, Maria do Socorro; Napoleão, Thiago Henrique; Paiva, Patrícia Maria Guedes; de Almeida Catanho, Maria Teresa Jansem; Coelho, Luana Cassandra Breitenbach Barroso

    2012-10-01

    Lectins, proteins that recognize carbohydrates, have been immobilized on inert supports and used in the screening or purification of glycoproteins. Anacardium occidentale bark infusion has been used as a hypoglycemic agent in Brazil. The toxicity of natural products may be evaluated determining their capability to alter the biodistribution of technetium-99M ((99m)Tc). This work reports the isolation and characterization of a lectin from A. occidentale bark (AnocBL), its evaluation as an affinity support for glycoprotein isolation and lectin effect on the uptake of (99m)Tc by rat adipocytes. AnocBL was isolated from 80 % ammonium sulphate supernatant by affinity chromatography on fetuin-agarose. SDS-PAGE showed a single protein band of 47 kDa. The monossacharide L-arabinose and the glycoproteins fetuin, asialofetuin, ovomucoid, casein, thyroglobulin, peroxidase, fetal bovine serum and IgG inhibited the activity. The lectin activity was stable until 70 °C and at a pH range of 3.0-7.5. AnocBL-Sepharose column bound fetuin indicating that the lectin matrix may be used to obtain glycoconjugates of biotechnological interest. In vitro assay revealed that glucose and insulin increase (99m)Tc uptake by rat adipocytes. AnocBL decreases (99m)Tc uptake, and this effect was not detected in the presence of glucose. Fetuin inhibited AnocBL effect in all insulin concentrations.

  1. Regulation of myosin IIA and filamentous actin during insulin-stimulated glucose uptake in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Stall, Richard; Ramos, Joseph; Kent Fulcher, F.; Patel, Yashomati M., E-mail: ympatel@uncg.edu

    2014-03-10

    Insulin stimulated glucose uptake requires the colocalization of myosin IIA (MyoIIA) and the insulin-responsive glucose transporter 4 (GLUT4) at the plasma membrane for proper GLUT4 fusion. MyoIIA facilitates filamentous actin (F-actin) reorganization in various cell types. In adipocytes F-actin reorganization is required for insulin-stimulated glucose uptake. What is not known is whether MyoIIA interacts with F-actin to regulate insulin-induced GLUT4 fusion at the plasma membrane. To elucidate the relationship between MyoIIA and F-actin, we examined the colocalization of MyoIIA and F-actin at the plasma membrane upon insulin stimulation as well as the regulation of this interaction. Our findings demonstrated that MyoIIA and F-actin colocalized at the site of GLUT4 fusion with the plasma membrane upon insulin stimulation. Furthermore, inhibition of MyoII with blebbistatin impaired F-actin localization at the plasma membrane. Next we examined the regulatory role of calcium in MyoIIA-F-actin colocalization. Reduced calcium or calmodulin levels decreased colocalization of MyoIIA and F-actin at the plasma membrane. While calcium alone can translocate MyoIIA it did not stimulate F-actin accumulation at the plasma membrane. Taken together, we established that while MyoIIA activity is required for F-actin localization at the plasma membrane, it alone is insufficient to localize F-actin to the plasma membrane. - Highlights: • Insulin induces colocalization of MyoIIA and F-actin at the cortex in adipocytes. • MyoIIA is necessary but not sufficient to localize F-actin at the cell cortex. • MyoIIA-F-actin colocalization is regulated by calcium and calmodulin.

  2. The relationship of omental and subcutaneous adipocyte size to metabolic disease in severe obesity.

    LENUS (Irish Health Repository)

    O'Connell, Jean

    2012-02-01

    OBJECTIVE: Several studies have reported the existence of a subgroup of obese individuals with normal metabolic profiles. It remains unclear what factors are responsible for this phenomenon. We proposed that adipocyte size might be a key factor in the protection of metabolically healthy obese (MHO) individuals from the adverse effects of obesity. SUBJECTS: Thirty-five patients undergoing bariatric surgery were classified as MHO (n = 15) or metabolically unhealthy obese (MUO, n = 20) according to cut-off points adapted from the International Diabetes Federation definition of the metabolic syndrome. Median body mass index (BMI) was 48 (range 40-71). RESULTS: There was a moderate correlation between omental adipocyte size and subcutaneous adipocyte size (r = 0.59, p<0.05). The MHO group had significantly lower mean omental adipocyte size (80.9+\\/-10.9 microm) when compared with metabolically unhealthy patients (100.0+\\/-7.6 microm, p<0.0001). Mean subcutaneous adipocyte size was similar between the two groups (104.1+\\/-8.5 microm versus 107.9+\\/-7.1 microm). Omental, but not subcutaneous adipocyte size, correlated with the degree of insulin resistance as measured by HOMA-IR (r = 0.73, p<0.0005), as well as other metabolic parameters including triglyceride\\/HDL-cholesterol ratio and HbA1c. Twenty-eight patients consented to liver biopsy. Of these, 46% had steatohepatitis and fibrosis. Fifty percent (including all the MHO patients) had steatosis only. Both omental and subcutaneous adipocyte size were significantly associated with the degree of steatosis (r = 0.66, p<0.0001 and r = 0.63, p<0.005 respectively). However, only omental adipocyte size was an independent predictor of the presence or absence of fibrosis. CONCLUSION: Metabolically healthy individuals are a distinct subgroup of the severely obese. Both subcutaneous and omental adipocyte size correlated positively with the degree of fatty liver, but only omental adipocyte size was related to metabolic health

  3. CD1d-mediated presentation of endogenous lipid antigens by adipocytes requires microsomal triglyceride transfer protein (MTP)

    DEFF Research Database (Denmark)

    Rakhshandehroo, Maryam; Gijzel, Sanne M W; Siersbæk, Rasmus

    2014-01-01

    microsomal triglyceride transfer protein (MTP), which we show is also under the transcriptional regulation of C/EBPβ and -δ, as a novel player in the presentation of endogenous lipid antigens by adipocytes. Overall, our findings indicate that adipocytes can function as non-professional lipid antigen...... presenting cells (APCs), which may present an important aspect of adipocyte-immune cell communication in the regulation of whole body energy metabolism and immune homeostasis....

  4. Gender Differences in Adipocyte Metabolism and Liver Cancer Progression

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    Otto Ka-Wing Cheung

    2016-09-01

    Full Text Available Liver cancer is the third most common cancer type and the second leading cause of deaths in men. Large population studies have demonstrated remarkable gender disparities in the incidence and the cumulative risk of liver cancer. A number of emerging risk factors regarding metabolic alterations associated with obesity, diabetes and dyslipidemia have been ascribed to the progression of non-alcoholic fatty liver diseases (NAFLD and ultimately liver cancer. The deregulation of fat metabolism derived from excessive insulin, glucose and lipid promotes cancer-causing inflammatory signaling and oxidative stress, which eventually triggers the uncontrolled hepatocellular proliferation. This review presents the current standing on the gender differences in body fat compositions and their mechanistic linkage with the development of NAFLD-related liver cancer, with an emphasis on genetic, epigenetic and microRNA control. The potential roles of sex hormones in instructing adipocyte metabolic programs may help unravel the mechanisms underlying gender dimorphism in liver cancer and identify the metabolic targets for disease management.

  5. Lipolytic actions of secretin in mouse adipocytes[S

    Science.gov (United States)

    Sekar, Revathi; Chow, Billy K. C.

    2014-01-01

    Secretin (Sct), a classical gut hormone, is now known to play pleiotropic functions in the body including osmoregulation, digestion, and feeding control. As Sct has long been implicated to regulate metabolism, in this report, we have investigated a potential lipolytic action of Sct. In our preliminary studies, both Sct levels in circulation and Sct receptor (SctR) transcripts in adipose tissue were upregulated during fasting, suggesting a potential physiological relevance of Sct in regulating lipolysis. Using SctR knockout and Sct knockout mice as controls, we show that Sct is able to stimulate lipolysis in vitro in isolated adipocytes dose- and time-dependently, as well as acute lipolysis in vivo. H-89, a protein kinase A (PKA) inhibitor, was found to attenuate lipolytic effects of 1 μM Sct in vitro, while a significant increase in PKA activity upon Sct injection was observed in the adipose tissue in vivo. Sct was also found to stimulate phosphorylation at 660ser of hormone sensitive lipase (HSL) and to bring about the translocation of HSL from cytosol to the lipid droplet. In summary, our data demonstrate for the first time the in vivo and in vitro lipolytic effects of Sct, and that this function is mediated by PKA and HSL. PMID:24273196

  6. A 68-year old male presenting with rhabdomyolysis-associated acute kidney injury following concomitant use of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate and pravastatin/fenofibrate: a case report

    OpenAIRE

    Suttels, Veronique; Florence, Eric; Leys, John; Vekemans, Marc; Van den Ende, Jef; Vlieghe, Erika; Kenyon, Chris

    2015-01-01

    Introduction We present what we believe to be the first case in the literature of rhabdomyolysis-induced renal failure caused by a probable drug interaction between elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF) and pravastatin/fenofibrate. Case presentation A 68-year old Caucasian man presented with progressive pain in both legs two weeks after commencing treatment with EVG/COBI/FTC/TDF. He was found to have biochemical evidence of rhabdomyolysis and a...

  7. Nitric oxide production from rat adipocytes is modulated beta3-adrenergic receptor agonists and is involved in a vycliv AMP-dependent lipolysis in adipocytes

    Czech Academy of Sciences Publication Activity Database

    Kutinová-Canová, N.; Lincová, D.; Kmoníčková, Eva; Kameníková, L.; Farghali, H.

    2006-01-01

    Roč. 14, - (2006), s. 200-211 ISSN 1089-8603 R&D Projects: GA MZd NL7418; GA ČR GA305/05/2425 Institutional research plan: CEZ:AV0Z50390512 Keywords : Lipolysis * Nitric oxide * Rat adipocytes Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.509, year: 2006

  8. CD1d-restricted NKT cell function prevents insulin resistance in lean mice, and is regulated by adipocytes and is regulated by adipocytes

    NARCIS (Netherlands)

    Schipper, Henk S.; Rakhshandehroo, Maryam; Graaf, van de Stan F.; Venken, Koen; Koppen, Arjen; Stienstra, Rinke; Prop, Serge; Meerding, Jenny; Hamers, Nicole; Besra, Gurdyal; Boon, Louis; Nieuwenhuis, Edward E.; Elewaut, Dirk; Prakken, Berent; Kersten, Sander; Boes, Marianne; Kalkhoven, Eric

    2012-01-01

    Lipid overload and adipocyte dysfunction are key to the development of insulin resistance and can be induced by a high-fat diet. CD1d-restricted invariant natural killer T (iNKT) cells have been proposed as mediators between lipid overload and insulin resistance, but recent studies found decreased

  9. Pmch-deficiency in rats is associated with normal adipocyte differentiation and lower sympathetic adipose drive.

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    Joram D Mul

    Full Text Available The orexigenic neuropeptide melanin-concentrating hormone (MCH, a product of Pmch, is an important mediator of energy homeostasis. Pmch-deficient rodents are lean and smaller, characterized by lower food intake, body-, and fat mass. Pmch is expressed in hypothalamic neurons that ultimately are components in the sympathetic nervous system (SNS drive to white and interscapular brown adipose tissue (WAT, iBAT, respectively. MCH binds to MCH receptor 1 (MCH1R, which is present on adipocytes. Currently it is unknown if Pmch-ablation changes adipocyte differentiation or sympathetic adipose drive. Using Pmch-deficient and wild-type rats on a standard low-fat diet, we analyzed dorsal subcutaneous and perirenal WAT mass and adipocyte morphology (size and number throughout development, and indices of sympathetic activation in WAT and iBAT during adulthood. Moreover, using an in vitro approach we investigated the ability of MCH to modulate 3T3-L1 adipocyte differentiation. Pmch-deficiency decreased dorsal subcutaneous and perirenal WAT mass by reducing adipocyte size, but not number. In line with this, in vitro 3T3-L1 adipocyte differentiation was unaffected by MCH. Finally, adult Pmch-deficient rats had lower norepinephrine turnover (an index of sympathetic adipose drive in WAT and iBAT than wild-type rats. Collectively, our data indicate that MCH/MCH1R-pathway does not modify adipocyte differentiation, whereas Pmch-deficiency in laboratory rats lowers adiposity throughout development and sympathetic adipose drive during adulthood.

  10. Direct evidence of brown adipocytes in different fat depots in children.

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    Denise Rockstroh

    Full Text Available Recent studies suggested the persistence of brown adipocytes in adult humans, as opposed to being exclusively present in infancy. In this study, we investigated the presence of brown-like adipocytes in adipose tissue (AT samples of children and adolescents aged 0 to 18 years and evaluated the association with age, location, and obesity. For this, we analysed AT samples from 131 children and 23 adults by histological, immunohistochemical and expression analyses. We detected brown-like and UCP1 positive adipocytes in 10.3% of 87 lean children (aged 0.3 to 10.7 years and in one overweight infant, whereas we did not find brown adipocytes in obese children or adults. In our samples, the brown-like adipocytes were interspersed within white AT of perirenal, visceral and also subcutaneous depots. Samples with brown-like adipocytes showed an increased expression of UCP1 (>200fold, PRDM16 (2.8fold, PGC1α and CIDEA while other brown/beige selective markers, such as PAT2, P2RX5, ZIC1, LHX8, TMEM26, HOXC9 and TBX1 were not significantly different between UCP1 positive and negative samples. We identified a positive correlation between UCP1 and PRDM16 within UCP1 positive samples, but not with any other brown/beige marker. In addition, we observed significantly increased PRDM16 and PAT2 expression in subcutaneous and visceral AT samples with high UCP1 expression in adults. Our data indicate that brown-like adipocytes are present well beyond infancy in subcutaneous depots of non-obese children. The presence was not restricted to typical perirenal locations, but they were also interspersed within WAT of visceral and subcutaneous depots.

  11. Adipocyte dysfunction in a mouse model of polycystic ovary syndrome (PCOS: evidence of adipocyte hypertrophy and tissue-specific inflammation.

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    Joseph S Marino

    Full Text Available Clinical research shows an association between polycystic ovary syndrome (PCOS and chronic inflammation, a pathological state thought to contribute to insulin resistance. The underlying pathways, however, have not been defined. The purpose of this study was to characterize the inflammatory state of a novel mouse model of PCOS. Female mice lacking leptin and insulin receptors in pro-opiomelanocortin neurons (IR/LepR(POMC mice and littermate controls were evaluated for estrous cyclicity, ovarian and adipose tissue morphology, and body composition by QMR and CT scan. Tissue-specific macrophage infiltration and cytokine mRNA expression were measured, as well as circulating cytokine levels. Finally, glucose regulation during pregnancy was evaluated as a measure of risk for diabetes development. Forty-five percent of IR/LepR(POMC mice showed reduced or absent ovulation. IR/LepR(POMC mice also had increased fat mass and adipocyte hypertrophy. These traits accompanied elevations in macrophage accumulation and inflammatory cytokine production in perigonadal adipose tissue, liver, and ovary. These mice also exhibited gestational hyperglycemia as predicted. This report is the first to show the presence of inflammation in IR/LepR(POMC mice, which develop a PCOS-like phenotype. Thus, IR/LepR(POMC mice may serve as a new mouse model to clarify the involvement of adipose and liver tissue in the pathogenesis and etiology of PCOS, allowing more targeted research on the development of PCOS and potential therapeutic interventions.

  12. Quercetin inhibits adipogenesis of muscle progenitor cells in vitro

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    Tomoko Funakoshi

    2018-03-01

    Full Text Available Muscle satellite cells are committed myogenic progenitors capable of contributing to myogenesis to maintain adult muscle mass and function. Several experiments have demonstrated that muscle satellite cells can differentiate into adipocytes in vitro, supporting the mesenchymal differentiation potential of these cells. Moreover, muscle satellite cells may be a source of ectopic muscle adipocytes, explaining the lipid accumulation often observed in aged skeletal muscle (sarcopenia and in muscles of patients` with diabetes. Quercetin, a polyphenol, is one of the most abundant flavonoids distributed in edible plants, such as onions and apples, and possesses antioxidant, anticancer, and anti-inflammatory properties. In this study, we examined whether quercetin inhibited the adipogenesis of muscle satellite cells in vitro with primary cells from rat limbs by culture in the presence of quercetin under adipogenic conditions. Morphological observations, Oil Red-O staining results, triglyceride content analysis, and quantitative reverse transcription polymerase chain reaction revealed that quercetin was capable of inhibiting the adipogenic induction of muscle satellite cells into adipocytes in a dose-dependent manner by suppressing the transcript levels of adipogenic markers, such as peroxisome proliferator-activated receptor-γ and fatty acid binding protein 4. Our results suggested that quercetin inhibited the adipogenesis of muscle satellite cells in vitro by suppressing the transcription of adipogenic markers. Keywords: Quercetin, Muscle satellite cell, Differentiation, Intramuscular lipid

  13. Glycerol Production from Glucose and Fructose by 3T3-L1 Cells: A Mechanism of Adipocyte Defense from Excess Substrate.

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    María del Mar Romero

    Full Text Available Cultured adipocytes (3T3-L1 produce large amounts of 3C fragments; largely lactate, depending on medium glucose levels. Increased glycolysis has been observed also in vivo in different sites of rat white adipose tissue. We investigated whether fructose can substitute glucose as source of lactate, and, especially whether the glycerol released to the medium was of lipolytic or glycolytic origin. Fructose conversion to lactate and glycerol was lower than that of glucose. The fast exhaustion of medium glucose was unrelated to significant changes in lipid storage. Fructose inhibited to a higher degree than glucose the expression of lipogenic enzymes. When both hexoses were present, the effects of fructose on gene expression prevailed over those of glucose. Adipocytes expressed fructokinase, but not aldolase b. Substantive release of glycerol accompanied lactate when fructose was the substrate. The mass of cell triacylglycerol (and its lack of change could not justify the comparatively higher amount of glycerol released. Consequently, most of this glycerol should be derived from the glycolytic pathway, since its lipolytic origin could not be (quantitatively sustained. Proportionally (with respect to lactate plus glycerol, more glycerol was produced from fructose than from glucose, which suggests that part of fructose was catabolized by the alternate (hepatic fructose pathway. Earlier described adipose glycerophophatase activity may help explain the glycolytic origin of most of the glycerol. However, no gene is known for this enzyme in mammals, which suggests that this function may be carried out by one of the known phosphatases in the tissue. Break up of glycerol-3P to yield glycerol, may be a limiting factor for the synthesis of triacylglycerols through control of glycerol-3P availability. A phosphatase pathway such as that described may have a potential regulatory function, and explain the production of glycerol by adipocytes in the absence of

  14. Insulin-Like Growth Factor (IGF Binding Protein-2, Independently of IGF-1, Induces GLUT-4 Translocation and Glucose Uptake in 3T3-L1 Adipocytes

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    Biruhalem Assefa

    2017-01-01

    Full Text Available Insulin-like growth factor binding protein-2 (IGFBP-2 is the predominant IGF binding protein produced during adipogenesis and is known to increase the insulin-stimulated glucose uptake (GU in myotubes. We investigated the IGFBP-2-induced changes in basal and insulin-stimulated GU in adipocytes and the underlying mechanisms. We further determined the role of insulin and IGF-1 receptors in mediating the IGFBP-2 and the impact of IGFBP-2 on the IGF-1-induced GU. Fully differentiated 3T3-L1 adipocytes were treated with IGFBP-2 in the presence and absence of insulin and IGF-1. Insulin, IGF-1, and IGFBP-2 induced a dose-dependent increase in GU. IGFBP-2 increased the insulin-induced GU after long-term incubation. The IGFBP-2-induced impact on GU was neither affected by insulin or IGF-1 receptor blockage nor by insulin receptor knockdown. IGFBP-2 significantly increased the phosphorylation of PI3K, Akt, AMPK, TBC1D1, and PKCζ/λ and induced GLUT-4 translocation. Moreover, inhibition of PI3K and AMPK significantly reduced IGFBP-2-stimulated GU. In conclusion, IGFBP-2 stimulates GU in 3T3-L1 adipocytes through activation of PI3K/Akt, AMPK/TBC1D1, and PI3K/PKCζ/λ/GLUT-4 signaling. The stimulatory effect of IGFBP-2 on GU is independent of its binding to IGF-1 and is possibly not mediated through the insulin or IGF-1 receptor. This study highlights the potential role of IGFBP-2 in glucose metabolism.

  15. Distinct adipocyte progenitor cells are associated with regional phenotypes of perivascular aortic fat in mice

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    Khanh-Van Tran

    2018-03-01

    Full Text Available Objective: Perivascular adipose tissue depots around the aorta are regionally distinct and have specific functional properties. Thoracic aorta perivascular adipose tissue (tPVAT expresses higher levels of thermogenic genes and lower levels of inflammatory genes than abdominal aorta perivascular adipose tissue (aPVAT. It is not known whether this distinction is due to the in-vivo functional environment or to cell-autonomous traits that persist outside the in-vivo setting. In this study, we asked whether the progenitor cells in tPVAT and aPVAT have cell-autonomous traits that lead to formation of regionally distinct PVAT. Methods: We performed microarray analysis of thoracic and abdominal peri-aortic adipose tissues of C57Bl/6J mice to define gene expression profile of each depot. To derive adipocyte progenitor cells, C57Bl/6J mice were sacrificed and thoracic and abdominal aorta fragments were embedded in Matrigel and cultured under pro-angiogenic conditions. Adipogenesis was induced using the Ppar-γ agonist rosiglitazone, a thiazolidinedione (TZD. TZD-induced adipocyte populations were analyzed using immunofluorescence and qRT-PCR. Results: Microarray analysis showed that tPVAT expressed higher levels of transcription factors related brown adipose tissue development compared to aPVAT. Classic brown adipose tissue (BAT genes such as Ucp-1, Prdm16, Dio2, Slc27a displayed a concordant trend of higher level expression in tPVAT, while white adipose tissue (WAT genes such as Hoxc8, Nnat, Sncg, and Mest were expressed at a higher level in aPVAT. The adipokines resistin and retinol binding protein 4 were also higher in aPVAT. Furthermore, adipocyte progenitors from abdominal and thoracic aortic rings responded to TZD with expression of canonical adipocyte genes Acrp30, Plin1, and Glut4. Adipocytes differentiated from thoracic aorta progenitors displayed markedly higher induction of Ucp-1 and Cidea. Conclusions: Thoracic aorta PVAT expresses higher

  16. Transient hypoxia reprograms differentiating adipocytes for enhanced insulin sensitivity and triglyceride accumulation

    Science.gov (United States)

    Lu, Hongyun; Gao, Zhanguo; Zhao, Zhiyun; Weng, Jianping; Ye, Jianping

    2015-01-01

    Objective To investigate the impact of transient (2-4 h) hypoxia on metabolic reprogramming of adipocytes. Methods The impact of transient hypoxia on metabolic reprogramming was investigated in 3T3-L1 cells before and after differentiation. Glucose uptake, fatty acid oxidation, lipolysis, and mitochondria were examined to determine the hypoxia effects. Preadipocytes were exposed to transient hypoxia (4h/day) in the course of differentiation. Insulin sensitivity and TG accumulation was examined in the cells at the end of differentiation to determine the reprogramming effects. AMPK activity and gene expression were determined by quantitative RT-PCR and Western blotting in search for mechanism of the reprogramming. Results In acute response to hypoxia, adipocytes exhibited an increase in insulin-dependent and -independent glucose uptake. Fatty acid β-oxidation and pyruvate dehydrogenase (PDH) activity were decreased. Multiple exposures of differentiating adipocytes to transient hypoxia enhanced insulin signaling, TG accumulation, expression of antioxidant genes in differentiated adipocytes in the absence of hypoxia. The metabolic memory was associated with elevated AMPK activity and gene expression (GLUT1, PGC-1α, PPARγ, SREBP, NRF-1, ESRRα, LPL). The enhanced insulin sensitivity was blocked by an AMPK inhibitor. Conclusions Repeated exposure of differentiating adipocytes to transient hypoxia is able to reprogram the cells for increased TG accumulation and enhanced insulin sensitivity. The metabolic alterations were observed in post-differentiated cells under normoxia. The reprogramming involves AMPK activation and gene expression in the metabolic pathways in cytosol and mitochondria. PMID:26219415

  17. Endoplasmic reticulum stress suppresses lipin-1 expression in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Nobuhiko, E-mail: ntkhs@hoku-iryo-u.ac.jp [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, 2-1-1-1, Midorigaoka-Higashi, Asahikawa, Hokkaido 078-8510 (Japan); Yoshizaki, Takayuki [Innovation Center, Kagoshima University, 1-21-40, Korimoto, Kagoshima 890-0065 (Japan); Hiranaka, Natsumi; Suzuki, Takeshi [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Yui, Tomoo; Akanuma, Masayoshi [Department of Fixed Prosthodontics and Oral Implantology, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Kanazawa, Kaoru [Department of Dental Anesthesiology, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Yoshida, Mika; Naito, Sumiyoshi [Department of Clinical Laboratory, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Fujiya, Mikihiro; Kohgo, Yutaka [Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, 2-1-1-1, Midorigaoka-Higashi, Asahikawa, Hokkaido 078-8510 (Japan); Ieko, Masahiro [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan)

    2013-02-01

    Highlights: ► Lipin-1 involves lipid metabolism, adipocyte differentiation, and inflammation. ► Adipose lipin-1 expression is reduced in obesity. ► ER stress suppresses lipin-1 expression in 3T3-L1 adipocytes. ► Activation of PPAR-γ recovers ER stress-induced lipin-1 reduction. -- Abstract: Lipin-1 plays crucial roles in the regulation of lipid metabolism and cell differentiation in adipocytes. In obesity, adipose lipin-1 mRNA expression is decreased and positively correlated with systemic insulin sensitivity. Amelioration of the lipin-1 depletion might be improved dysmetabolism. Although some cytokines such as TNF-α and interleukin-1β reduces adipose lipin-1 expression, the mechanism of decreased adipose lipin-1 expression in obesity remains unclear. Recently, endoplasmic reticulum (ER) stress is implicated in the pathogenesis of obesity. Here we investigated the role of ER stress on the lipin-1 expression in 3T3-L1 adipocytes. We demonstrated that lipin-1 expression was suppressed by the treatment with ER stress inducers (tunicamycin and thapsigargin) at transcriptional level. We also showed that constitutive lipin-1 expression could be maintained by peroxisome proliferator-activated receptor-γ in 3T3-L1 adipocytes. Activation of peroxisome proliferator-activated receptor-γ recovered the ER stress-induced lipin-1 suppression. These results suggested that ER stress might be involved in the pathogenesis of obesity through lipin-1 depletion.

  18. Endoplasmic reticulum stress suppresses lipin-1 expression in 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Takahashi, Nobuhiko; Yoshizaki, Takayuki; Hiranaka, Natsumi; Suzuki, Takeshi; Yui, Tomoo; Akanuma, Masayoshi; Kanazawa, Kaoru; Yoshida, Mika; Naito, Sumiyoshi; Fujiya, Mikihiro; Kohgo, Yutaka; Ieko, Masahiro

    2013-01-01

    Highlights: ► Lipin-1 involves lipid metabolism, adipocyte differentiation, and inflammation. ► Adipose lipin-1 expression is reduced in obesity. ► ER stress suppresses lipin-1 expression in 3T3-L1 adipocytes. ► Activation of PPAR-γ recovers ER stress-induced lipin-1 reduction. -- Abstract: Lipin-1 plays crucial roles in the regulation of lipid metabolism and cell differentiation in adipocytes. In obesity, adipose lipin-1 mRNA expression is decreased and positively correlated with systemic insulin sensitivity. Amelioration of the lipin-1 depletion might be improved dysmetabolism. Although some cytokines such as TNF-α and interleukin-1β reduces adipose lipin-1 expression, the mechanism of decreased adipose lipin-1 expression in obesity remains unclear. Recently, endoplasmic reticulum (ER) stress is implicated in the pathogenesis of obesity. Here we investigated the role of ER stress on the lipin-1 expression in 3T3-L1 adipocytes. We demonstrated that lipin-1 expression was suppressed by the treatment with ER stress inducers (tunicamycin and thapsigargin) at transcriptional level. We also showed that constitutive lipin-1 expression could be maintained by peroxisome proliferator-activated receptor-γ in 3T3-L1 adipocytes. Activation of peroxisome proliferator-activated receptor-γ recovered the ER stress-induced lipin-1 suppression. These results suggested that ER stress might be involved in the pathogenesis of obesity through lipin-1 depletion

  19. Consequence of Menin Deficiency in Mouse Adipocytes Derived by In Vitro Differentiation

    Directory of Open Access Journals (Sweden)

    Vaishali I. Parekh

    2015-01-01

    Full Text Available Lipoma in patients with the multiple endocrine neoplasia type 1 (MEN1 syndrome is a type of benign fat-cell tumor that has biallelic inactivation of MEN1 that encodes menin and could serve as a model to investigate normal and pathologic fat-cell (adipocyte proliferation and function. The role of menin and its target genes in adipocytes is not known. We used in vitro differentiation to derive matched normal and menin-deficient adipocytes from wild type (WT and menin-null (Men1-KO mouse embryonic stem cells (mESCs, respectively, or 3T3-L1 cells without or with menin knockdown to investigate cell size, lipid content, and gene expression changes. Adipocytes derived from Men1-KO mESCs or after menin knockdown in 3T3-L1 cells showed a 1.5–1.7-fold increase in fat-cell size. Global gene expression analysis of mESC-derived adipocytes showed that lack of menin downregulated the expression of many differentially methylated genes including the tumor suppressor long noncoding RNA Meg3 but upregulated gene expression from the prolactin gene family locus. Our results show that menin deficiency leads to fat-cell hypertrophy and provide model systems that could be used to study the regulation of fat-cell size.

  20. Microparticles release by adipocytes act as "find-me" signals to promote macrophage migration.

    Science.gov (United States)

    Eguchi, Akiko; Mulya, Anny; Lazic, Milos; Radhakrishnan, Deepa; Berk, Michael P; Povero, Davide; Gornicka, Agnieszka; Feldstein, Ariel E

    2015-01-01

    Macrophage infiltration of adipose tissue during weight gain is a central event leading to the metabolic complications of obesity. However, what are the mechanisms attracting professional phagocytes to obese adipose tissue remains poorly understood. Here, we demonstrate that adipocyte-derived microparticles (MPs) are critical "find-me" signals for recruitment of monocytes and macrophages. Supernatants from stressed adipocytes stimulated the attraction of monocyte cells and primary macrophages. The activation of caspase 3 was required for release of these signals. Adipocytes exposed to saturated fatty acids showed marked release of MPs into the supernatant while common genetic mouse models of obesity demonstrate high levels of circulating adipocyte-derived MPs. The release of MPs was highly regulated and depende