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Sample records for hypoxia stimulates proliferation

  1. Hypoxia promotes adipose-derived stem cell proliferation via VEGF

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    Phuc Van Pham

    2016-01-01

    Full Text Available Adipose-derived stem cells (ADSCs are a promising mesenchymal stem cell source with therapeutic applications. Recent studies have shown that ADSCs could be expanded in vitro without phenotype changes. This study aimed to evaluate the effect of hypoxia on ADSC proliferation in vitro and to determine the role of vascular endothelial growth factor (VEGF in ADSC proliferation. ADSCs were selectively cultured from the stromal vascular fraction obtained from adipose tissue in DMEM/F12 medium supplemented with 10% fetal bovine serum and 1% antibiotic-antimycotic. ADSCs were cultured under two conditions: hypoxia (5% O2 and normal oxygen (21% O2. The effects of the oxygen concentration on cell proliferation were examined by cell cycle and doubling time. The expression of VEGF was evaluated by the ELISA assay. The role of VEGF in ADSC proliferation was studied by neutralizing VEGF with anti-VEGF monoclonal antibodies. We found that the ADSC proliferation rate was significantly higher under hypoxia compared with normoxia. In hypoxia, ADSCs also triggered VEGF expression. However, neutralizing VEGF with anti-VEGF monoclonal antibodies significantly reduced the proliferation rate. These results suggest that hypoxia stimulated ADSC proliferation in association with VEGF production. [Biomed Res Ther 2016; 3(1.000: 476-482

  2. Chronic hypoxia promotes pulmonary artery endothelial cell proliferation through H2O2-induced 5-lipoxygenase.

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    Kristi M Porter

    Full Text Available Pulmonary Hypertension (PH is a progressive disorder characterized by endothelial dysfunction and proliferation. Hypoxia induces PH by increasing vascular remodeling. A potential mediator in hypoxia-induced PH development is arachidonate 5-Lipoxygenase (ALOX5. While ALOX5 metabolites have been shown to promote pulmonary vasoconstriction and endothelial cell proliferation, the contribution of ALOX5 to hypoxia-induced proliferation remains unknown. We hypothesize that hypoxia exposure stimulates HPAEC proliferation by increasing ALOX5 expression and activity. To test this, human pulmonary artery endothelial cells (HPAEC were cultured under normoxic (21% O2 or hypoxic (1% O2 conditions for 24-, 48-, or 72 hours. In a subset of cells, the ALOX5 inhibitor, zileuton, or the 5-lipoxygenase activating protein inhibitor, MK-886, was administered during hypoxia exposure. ALOX5 expression was measured by qRT-PCR and western blot and HPAEC proliferation was assessed. Our results demonstrate that 24 and 48 hours of hypoxia exposure have no effect on HPAEC proliferation or ALOX5 expression. Seventy two hours of hypoxia significantly increases HPAEC ALOX5 expression, hydrogen peroxide (H2O2 release, and HPAEC proliferation. We also demonstrate that targeted ALOX5 gene silencing or inhibition of the ALOX5 pathway by pharmacological blockade attenuates hypoxia-induced HPAEC proliferation. Furthermore, our findings indicate that hypoxia-induced increases in cell proliferation and ALOX5 expression are dependent on H2O2 production, as administration of the antioxidant PEG-catalase blocks these effects and addition of H2O2 to HPAEC promotes proliferation. Overall, these studies indicate that hypoxia exposure induces HPAEC proliferation by activating the ALOX5 pathway via the generation of H2O2.

  3. Scutellarein inhibits hypoxia- and moderately-high glucose-induced proliferation and VEGF expression in human retinal endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Rong GAO; Bang-hao ZHU; Shi-bo TANG; Jiang-feng WANG; Jun REN

    2008-01-01

    Aim: This study was designed to examine the effect of scutellarein on high glu-cose- and hypoxia-stimulated proliferation of human retinal endothelial cells (HREC). Methods: HREC were cultured under normal glucose (NG), moderate, and high glucose (NG supplemented with 10 or 25 mmol/L D-glucose) and/or hypoxic (cobalt chloride treated) conditions. Cell proliferation was evaluated by a cell counting kit. The expression of vascular endothelial growth factor (VEGF) was assessed by Western blot analysis. Results: The proliferation of HREC was significantly elevated in response to moderately-high glucose and hypoxic conditions. The combination of high glucose and hypoxia did not have any additive effects on cell proliferation. Consistent with the proliferation data, the expression of VEGF was also upregulated under both moderately-high glucose and hypoxic conditions. The treatment with scutellarein (1 × 10-11-1 × 10-5 mol/L) significantly inhibited high glucose- or hypoxia-induced cell proliferation and VEGF expression. Conclusion: Both hypoxia and moderately-high glucose were potent stimuli for cell proliferation and VEGF expression in HREC without any significant additive effects. Scutellarein is capable of inhibiting the proliferation of HREC, which is possibly related to its ability to suppress the VEGF expression.

  4. Effect of Angelica sinensis on neural stem cell proliferation in neonatal rats following intrauterine hypoxia

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    Hesheng Yue; Xudong Chen; Xiaoming Zhong; Hong Yu

    2008-01-01

    hypoxia group.Integral absorbance of nestin-positive cells in the hippocampal CA3 area of neonatal rats was significantly higher in the hypoxia group,compared with the control group(P<0.05).The integral absorbance of nestin positive cells was lower in the Angelica group,compared with the hypoxia group(P<0.05).CONCLUSION:Intrauterine hypoxia,induced for 2 hours daily for three consecutive days,with an oxygen concentration of 13%,stimulated the proliferation of neural stem cells.Angelica injection has a protective effect on neural stem cells from neonatal rats following intrauterine hypoxia by decreasing proliferation of neural stem cells.

  5. Novel Pathway for Hypoxia-Induced Proliferation and Migration in Human Mesenchymal Stem Cells: Involvement of HIF-1α, FASN, and mTORC1.

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    Lee, Hyun Jik; Ryu, Jung Min; Jung, Young Hyun; Oh, Sang Yub; Lee, Sei-Jung; Han, Ho Jae

    2015-07-01

    The control of stem cells by oxygen signaling is an important way to improve various stem cell physiological functions and metabolic nutrient alteration. Lipid metabolism alteration via hypoxia is thought to be a key factor in controlling stem cell fate and function. However, the interaction between hypoxia and the metabolic and functional changes to stem cells is incompletely described. This study aimed to identify hypoxia-inducible lipid metabolic enzymes that can regulate umbilical cord blood (UCB)-derived human mesenchymal stem cell (hMSC) proliferation and migration and to demonstrate the signaling pathway that controls functional change in UCB-hMSCs. Our results indicate that hypoxia treatment stimulates UCB-hMSC proliferation, and expression of two lipogenic enzymes: fatty acid synthase (FASN) and stearoyl-CoA desaturase-1 (SCD1). FASN but not SCD1 is a key enzyme for regulation of UCB-hMSC proliferation and migration. Hypoxia-induced FASN expression was controlled by the hypoxia-inducible factor-1 alpha (HIF-1α)/SCAP/SREBP1 pathway. Mammalian target of rapamycin (mTOR) was phosphorylated by hypoxia, whereas inhibition of FASN by cerulenin suppressed hypoxia-induced mTOR phosphorylation as well as UCB-hMSC proliferation and migration. RAPTOR small interfering RNA transfection significantly inhibited hypoxia-induced proliferation and migration. Hypoxia-induced mTOR also regulated CDK2, CDK4, cyclin D1, cyclin E, and F-actin expression as well as that of c-myc, p-cofilin, profilin, and Rho GTPase. Taken together, the results suggest that mTORC1 mainly regulates UCB-hMSC proliferation and migration under hypoxia conditions via control of cell cycle and F-actin organization modulating factors. In conclusion, the HIF-1α/FASN/mTORC1 axis is a key pathway linking hypoxia-induced lipid metabolism with proliferation and migration in UCB-hMSCs. Stem Cells 2015;33:2182-2195.

  6. Acute normobaric hypoxia stimulates erythropoietin release.

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    Mackenzie, Richard W A; Watt, Peter W; Maxwell, Neil S

    2008-01-01

    Investigations studying the secretion of EPO (erythropoietin) in response to acute hypoxia have produced mixed results. Further, the errors associated with the various methods used to determine EPO are not well documented. The purpose of the current study was to determine the EPO response of 17 trained male subjects to either an acute bout of normobaric hypoxia (Hy; n = 10) or normoxia (Con; n = 7). A secondary aim was to determine the error associated with the measurement of EPO. After baseline tests, the treatment group (Hy) underwent a single bout of hypoxic exposure (F(I(O(2))) approximately 0.148; 3100 m) consisting of a 90-min rest period followed by a 30-min exercise phase (50% V(O)(2max)). Venous blood samples were drawn pre (0 min) and post (120 min) each test to assess changes in plasma EPO (DeltaEPO). The control (Con) group was subjected to the same general experimental design, but placed in a normoxic environment (F(I(O(2))) approximately 0.2093). The Hy group demonstrated a mean increase in EPO [19.3 (4.4) vs. 24.1 (5.1) mU/mL], p < 0.04, post 120 min of normobaric hypoxia. The calculated technical error of measurement for EPO was 2.1 mU/mL (9.8%). It was concluded that an acute bout of hypoxia, has the capacity to elevate plasma EPO. This study also demonstrates that the increase in EPO accumulation was 2 times greater than the calculated measurement of error.

  7. Cancer drug troglitazone stimulates the growth and response of renal cells to hypoxia inducible factors

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    Taub, Mary, E-mail: biochtau@buffalo.edu

    2016-03-11

    Troglitazone has been used to suppress the growth of a number of tumors through apoptosis and autophagy. However, previous in vitro studies have employed very high concentrations of troglitazone (≥10{sup −5} M) in order to elicit growth inhibitory effects. In this report, when employing lower concentrations of troglitazone in defined medium, troglitazone was observed to stimulate the growth of primary renal proximal tubule (RPT) cells. Rosiglitazone, like troglitazone, is a thiazolidinedione (TZD) that is known to activate Peroxisome Proliferator Activated Receptor Υ (PPARΥ). Notably, rosiglitazone also stimulates RPT cell growth, as does Υ-linolenic acids, another PPARΥ agonist. The PPARΥ antagonist GW9662 inhibited the growth stimulatory effect of troglitazone. In addition, troglitazone stimulated transcription by a PPAR Response Element/Luciferase construct. These results are consistent with the involvement of PPARΥ as a mediator of the growth stimulatory effect of troglitazone. In a number of tumor cells, the expression of hypoxia inducible factor (HIF) is increased, promoting the expression of HIF inducible genes, and vascularization. Troglitazone was observed to stimulate transcription by a HIF/luciferase construct. These observations indicate that troglitazone not only promotes growth, also the survival of RPT cells under conditions of hypoxia. - Highlights: • Troglitazone and rosiglitazone stimulate renal proximal tubule cell growth. • Troglitazone and linolenic acid stimulate growth via PPARϒ. • Linolenic acid stimulates growth in the presence of fatty acid free serum albumin. • Rosiglitazone stimulates transcription by a HRE luciferase construct.

  8. Harmine stimulates proliferation of human neural progenitors

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    Dakic, Vanja; Maciel, Renata de Moraes; Drummond, Hannah; Nascimento, Juliana M.; Trindade, Pablo

    2016-01-01

    Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive) derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A), which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY), and an irreversible selective inhibitor of monoamine oxidase (MAO) but not DYRK1A (pargyline). INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo. PMID:27957390

  9. Harmine stimulates proliferation of human neural progenitors

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    Vanja Dakic

    2016-12-01

    Full Text Available Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A, which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY, and an irreversible selective inhibitor of monoamine oxidase (MAO but not DYRK1A (pargyline. INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo.

  10. Modelling the interplay between hypoxia and proliferation in radiotherapy tumour response

    OpenAIRE

    2013-01-01

    A tumour control probability computational model for fractionated radiotherapy was developed, with the goal of incorporating the fundamental interplay between hypoxia and proliferation, including reoxygenation over a course of radiotherapy. The fundamental idea is that the local delivery of oxygen and glucose limits the amount of proliferation and metabolically-supported cell survival a tumour sub-volume can support. The model has three compartments: a proliferating compartment of cells recei...

  11. Effect of C-myc Antisense Oligodeoxynucleotides on Hypoxia-induced Proliferation of Pulmonary Vascular Pericytes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To study the effect of c-myc antisense oligodeoxynucleotides (ODNs) on proliferation of pulmonary vascular pericytes (PC) induced by hypoxia, cell culture, dot hybridization using probe of digoxigenin-11-dUTP-labeled cDNA,3H-thymidine incorporation, immunocytochemical technique and image analysis methods were used to observe the effect of c-myc antisense ODNs on expression of c-myc gene and proliferating cell nuclear antigen (PCNA), and 3H-thymidine incorporation of PC induced by hypoxia. The results showed that hypoxia could significantly enhance the expression of c-myc and PCNA (P<0.01), and elevate 3H-thymidine incorporation of PC (P<0.01), but antisense ODNs could significantly inhibit the expression of c-myc and PCNA (P<0.05), and 3H-thymidine incorporation of PC (P<0.01). It was suggested that hypoxia could promote the proliferation of PC by up-regulating the expression of c-myc gene, but c-myc antisense ODNs could inhibit hypoxia-induced proliferation of PC by downregulating the expression of c-myc gene.

  12. Hypoxia in relation to vasculature and proliferation in liver metastases in patients with colorectal cancer.

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    Laarhoven, H.W.M. van; Kaanders, J.H.A.M.; Lok, J.; Peeters, W.J.M.; Rijken, P.F.J.W.; Wiering, B.; Ruers, T.J.M.; Punt, C.J.A.; Heerschap, A.; Kogel, A.J. van der

    2006-01-01

    PURPOSE: To investigate hypoxia measured by pimonidazole binding, glucose transporter 1 (GLUT1) and carbonic anhydrase IX (CA-IX) expression, proliferation, and vascularity in liver metastases of colorectal cancer and to compare GLUT1 and CA-IX expression in corresponding primary tumors. METHODS AND

  13. Up-regulation of hypoxia inducible factor-1α by cobalt chloride correlates with proliferation and apoptosis in PC-2 cells

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    Dai Zhi-Jun

    2012-03-01

    Full Text Available Abstract Background The exact mechanism of the effects of hypoxia on the proliferation and apoptosis in carcinoma cells is still conflicting. This study investigated the variation of hypoxia-inducible factor-1α(HIF-1α expression and the apoptosis effect of hypoxia stimulated by cobalt chloride (CoCl2 in pancreatic cancer PC-2 cells. Methods PC-2 cells were cultured with different concentration (50-200 μmol/L of CoCl2 after 24-120 hours to simulate hypoxia in vitro. The proliferation of PC-2 cells was examined by MTT assay. The cellular morphology of PC-2 cells were observed by light inverted microscope and transmission electron microscope(EM. The expression of HIF-1α on mRNA and protein level was measured by semi-quantitive RT-PCR and Western blot analysis. Apoptosis of PC-2 cells were demonstrated by flow cytometry with Annexin V-FITC/PI double staining. Results MTT assay showed that the proliferation of PC-2 cells were stimulated in the first 72 h, while after treated over 72 h, a dose- dependent inhibition of cell growth could be observed. By using transmission electron microscope, swollen chondrosomes, accumulated chromatin under the nuclear membrane and apoptosis bodies were observed. Flow cytometer(FCM analysis showed the apoptosis rate was correlated with the dosage of CoCl2. RT-PCR and Western blot analysis indicated that hypoxia could up-regulate the expression of HIF-1α on both mRNA and protein levels. Conclusion Hypoxic microenvironment stimulated by CoCl2 could effectively induce apoptosis and influence cell proliferation in PC-2 cells, the mechanism could be related to up-expression of HIF-1α.

  14. Stanniocalcin-2 is a HIF-1 target gene that promotes cell proliferation in hypoxia

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    Law, Alice Y.S. [Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong); Wong, Chris K.C., E-mail: ckcwong@hkbu.edu.hk [Department of Biology, Hong Kong Baptist University, Kowloon Tong (Hong Kong)

    2010-02-01

    Stanniocalcin-2 (STC2), the paralog of STC1, has been suggested as a novel target of oxidative stress response to protect cells from apoptosis. The expression of STC2 has been reported to be highly correlated with human cancer development. In this study, we reported that STC2 is a HIF-1 target gene and is involved in the regulation of cell proliferation. STC2 was shown to be up-regulated in different breast and ovarian cancer cells, following exposure to hypoxia. Using ovarian cancer cells (SKOV3), the underlying mechanism of HIF-1 mediated STC2 gene transactivation was characterized. Hypoxia-induced STC2 expression was found to be HIF-1{alpha} dependent and required the recruitment of p300 and HDAC7. Using STC2 promoter deletion constructs and site-directed mutagenesis, two authentic consensus HIF-1 binding sites were identified. Under hypoxic condition, the silencing of STC2 reduced while the overexpression of STC2 increased the levels of phosphorylated retinoblastoma and cyclin D in both SKOV3 and MCF7 cells. The change in cell cycle proteins correlated with the data of the serial cell counts. The results indicated that cell proliferation was reduced in STC2-silenced cells but was increased in STC2-overexpressing hypoxic cells. Solid tumor progression is usually associated with hypoxia. The identification and functional analysis of STC2 up-regulation by hypoxia, a feature of the tumor microenvironment, sheds light on a possible role for STC2 in tumors.

  15. Airway Epithelium Stimulates Smooth Muscle Proliferation

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    Malavia, Nikita K.; Raub, Christopher B.; Mahon, Sari B.; Brenner, Matthew; Reynold A Panettieri; George, Steven C.

    2009-01-01

    Communication between the airway epithelium and stroma is evident during embryogenesis, and both epithelial shedding and increased smooth muscle proliferation are features of airway remodeling. Hence, we hypothesized that after injury the airway epithelium could modulate airway smooth muscle proliferation. Fully differentiated primary normal human bronchial epithelial (NHBE) cells at an air–liquid interface were co-cultured with serum-deprived normal primary human airway smooth muscle cells (...

  16. Mechanical stimulation increases proliferation, differentiation and protein expression in culture

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    Grossi, Alberto; Yadav, Kavita; Lawson, Moira Ann

    2007-01-01

    Myogenesis is a complex sequence of events, including the irreversible transition from the proliferation-competent myoblast stage into fused, multinucleated myotubes. Myogenic differentiation is regulated by positive and negative signals from surrounding tissues. Stimulation due to stretch- or lo...

  17. Mild hypoxia enhances proliferation and multipotency of human neural stem cells.

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    Guido Santilli

    Full Text Available BACKGROUND: Neural stem cells (NSCs represent an optimal tool for studies and therapy of neurodegenerative diseases. We recently established a v-myc immortalized human NSC (IhNSC line, which retains stem properties comparable to parental cells. Oxygen concentration is one of the most crucial environmental conditions for cell proliferation and differentiation both in vitro and in vivo. In the central nervous system, physiological concentrations of oxygen range from 0.55 to 8% oxygen. In particular, in the in the subventricular zone niche area, it's estimated to be 2.5 to 3%. METHODOLOGY/PRINCIPAL FINDINGS: We investigated in vitro the effects of 1, 2.5, 5, and 20% oxygen concentrations on IhNSCs both during proliferation and differentiation. The highest proliferation rate, evaluated through neurosphere formation assay, was obtained at 2.5 and 5% oxygen, while 1% oxygen was most noxious for cell survival. The differentiation assays showed that the percentages of beta-tubIII+ or MAP2+ neuronal cells and of GalC+ oligodendrocytes were significantly higher at 2.5% compared with 1, 5, or 20% oxygen at 17 days in vitro. Mild hypoxia (2.5 to 5% oxygen promoted differentiation into neuro-oligodendroglial progenitors as revealed by the higher percentage of MAP2+/Ki67+ and GalC+/Ki67+ residual proliferating progenitors, and enhanced the yield of GABAergic and slightly of glutamatergic neurons compared to 1% and 20% oxygen where a significant percentage of GFAP+/nestin+ cells were still present at 17 days of differentiation. CONCLUSIONS/SIGNIFICANCE: These findings raise the possibility that reduced oxygen levels occurring in neuronal disorders like cerebral ischemia transiently lead to NSC remaining in a state of quiescence. Conversely, mild hypoxia favors NSC proliferation and neuronal and oligodendroglial differentiation, thus providing an important advance and a useful tool for NSC-mediated therapy of ischemic stroke and neurodegenerative diseases like

  18. Nutrient-Deprived Retinal Progenitors Proliferate in Response to Hypoxia: Interaction of the HIF-1 and mTOR Pathway

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    Helena Khaliullina

    2016-05-01

    Full Text Available At a cellular level, nutrients are sensed by the mechanistic Target of Rapamycin (mTOR. The response of cells to hypoxia is regulated via action of the oxygen sensor Hypoxia-Inducible Factor 1 (HIF-1. During development, injury and disease, tissues might face conditions of both low nutrient supply and low oxygen, yet it is not clear how cells adapt to both nutrient restriction and hypoxia, or how mTOR and HIF-1 interact in such conditions. Here we explore this question in vivo with respect to cell proliferation using the ciliary marginal zone (CMZ of Xenopus. We found that both nutrient-deprivation and hypoxia cause retinal progenitors to decrease their proliferation, yet when nutrient-deprived progenitors are exposed to hypoxia there is an unexpected rise in cell proliferation. This increase, mediated by HIF-1 signalling, is dependent on glutaminolysis and reactivation of the mTOR pathway. We discuss how these findings in non-transformed tissue may also shed light on the ability of cancer cells in poorly vascularised solid tumours to proliferate.

  19. Stimulation of cell proliferation by calcium and a calcimimetic compound

    NARCIS (Netherlands)

    Mailland, M; Waelchli, R; Ruat, M; Boddeke, HGWM; Seuwen, K

    Some mesenchymal cells respond to stimulation by specific cations with increased cell proliferation. In the present study we have investigated whether the parathyroid/kidney/brain calcium-sensing receptor (PCaR) can mediate such mitogenic responses. We have expressed the recombinant rat PCaR in

  20. Increased cellular hypoxia and reduced proliferation of both normal and leukaemic cells during progression of acute myeloid leukaemia in rats

    DEFF Research Database (Denmark)

    Jensen, P O; Mortensen, B T; Hodgkiss, R J;

    2000-01-01

    The microenvironmental changes in the bone marrow, spleen and liver during progression of the transplantable promyelocytic leukaemia in the Brown Norwegian rat (BNML) have been studied. We used flow cytometry to estimate cellular hypoxia and proliferation based on in vivo pulse-labelling with a m......The microenvironmental changes in the bone marrow, spleen and liver during progression of the transplantable promyelocytic leukaemia in the Brown Norwegian rat (BNML) have been studied. We used flow cytometry to estimate cellular hypoxia and proliferation based on in vivo pulse...

  1. Carbon monoxide inhibits proliferation of pulmonary smooth muscle cells under hypoxia

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    甄国华; 张珍祥; 薛峥; 徐永健

    2003-01-01

    Objective To investigate the expression of inducible heme oxygenase (HO-1) gene in pulmonary artery smooth muscle cells (PASMCs) exposed to hypoxia, and the influence of carbon monoxide (CO) on the proliferation of PASMCs under hypoxic conditions.Methods Primary culture of rat PASMCs were passed every 3 days, and the 3-5 passages were used. After exposure to hypoxic conditions (95% N2, 5% CO2) 0, 12, 24 and 48 hours, the level of HO-1 mRNA was examined by reverse transcriptase polymerase chain reaction (RT-PCR). The volume of COHb in the medium was measured spectrophotometrically. The cyclic guanosine mono-phosphate (cGMP) concentration of cell extracts was determined by radioimmunoassay. PASMCs were divided into 5 groups, cultured under normoxia and hypoxia and treated with hemin, hemoglobin (Hb) and exogenous CO respectively. Then 3-(4, 5-cimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) colorimetric assay and immunocytochemical staining were used to study the energy metabolism and the expression of proliferating cell nuclear antigen (PCNA) in PASMCs. Flow cytometry was used to analyze the cell cycle of PASMCs.Results After exposure to hypoxic conditions for 12, 24, and 48 hours, the HO-1 mRNA increased by 2.7%, 5.7% and 27.1% respectively (P<0.01). The carboxy-hemoglobin (COHb) in the medium increased by 13.8%, 31.0% and 93.1% (P<0.01); the cGMP concentrations were 2.7, 4.0 and 6.8-fold compared with the control group (P<0.01 and P<0.05). In comparison with the control group, the value of MTT colorimetric assay, the immunocytochemical staining of PCNA and the percentages of PASMCs in S and G2M phases in the hypoxic group were significantly higher (P<0.01). After treatment with Hemin and CO, the results of the above analysis decreased significantly (P<0.01 and P<0.05), but increased significantly after treatment with Hb (P<0.01 and P<0.05).Conclusions The expression of HO-1 gene in PASMCs is upregulated by hypoxia and the production of endogenous CO

  2. Proliferation and apoptosis property of mesenchymal stem cells derived from peripheral blood under the culture conditions of hypoxia and serum deprivation

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    FU Wei-li; JIA Zhu-qing; WANG Wei-ping; ZHANG Ji-ying; FU Xin; DUAN Xiao-ning; LEUNG Kevin Kar Ming; ZHOU Chun-yan; YU Jia-kuo

    2011-01-01

    Background The proliferation and apoptosis property of mesenchymal stem cells derived from peripheral blood (PB-MSCs) were investigated under hypoxia and serum deprivation conditions in vitro so as to evaluate the feasibility for autologous PB-MSCs applications in cartilage repair.Methods MSCs were mobilized into peripheral blood by granulocyte colony stimulating factor (G-CSF) and AMD3100.The blood samples were collected from central ear artery of rabbits.Adhered cells were obtained by erythrocyte lysis buffer and identified as MSCs by adherence to plastic,spindle shaped morphology,specific surface markers,differentiation abilities into osteoblasts,adipocytes and chondroblasts in vitro under appropriate conditions.MSCs were cultured in four groups at different oxygen tension (20% O2 and 2% O2),with or without 10% fetal bovine serum (FBS)conditions:20% O2 and 10% FBS complete medium (normal medium,N),20% O2 and serum deprivation medium (D),2% O2 and 10% FBS complete medium (hypoxia,H),2% O2 and serum deprivation (HD).Cell proliferation was determined by CCK-8 assay.Apoptosis was detected by Annexin V/Pl and terminal deoxynucleotide transferase dUTP nick end labeling (TUNEL) staining.Results Spindle-shaped adherent cells were effectively mobilized from peripheral blood by a combined administration of G-CSF plus AMD3100.These cells showed typical fibroblast-like phenotype similar to MSCs from bone marrow (BM-MSCs),and expressed a high level of typical MSCs markers CD29 and CD44,but lacked in the expression of hematopoietic markers CD45 and major histocompatibility complex Class Ⅱ (MHC Ⅱ).They could also differentiate into osteoblasts,adipocytes and chondroblasts in vitro under appropriate conditions.No significant morphological differences were found among the four groups.It was found that hypoxia could enhance proliferation of PB-MSCs regardless of serum concentration,but serum deprivation inhibited proliferation at the later stage of culture

  3. Modelling the interplay between hypoxia and proliferation in radiotherapy tumour response

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    Jeong, J.; Shoghi, K. I.; Deasy, J. O.

    2013-07-01

    A tumour control probability computational model for fractionated radiotherapy was developed, with the goal of incorporating the fundamental interplay between hypoxia and proliferation, including reoxygenation over a course of radiotherapy. The fundamental idea is that the local delivery of oxygen and glucose limits the amount of proliferation and metabolically-supported cell survival a tumour sub-volume can support. The model has three compartments: a proliferating compartment of cells receiving oxygen and glucose; an intermediate, metabolically-active compartment receiving glucose; and a highly hypoxic compartment of starving cells. Following the post-mitotic cell death of proliferating cells, intermediate cells move into the proliferative compartment and hypoxic cells move into the intermediate compartment. A key advantage of the proposed model is that the initial compartmental cell distribution is uniquely determined from the assumed local growth fraction (GF) and volume doubling time (TD) values. Varying initial cell state distributions, based on the local (voxel) GF and TD, were simulated. Tumour response was simulated for head and neck squamous cell carcinoma using relevant parameter values based on published sources. The tumour dose required to achieve a 50% local control rate (TCD50) was found for various GFs and TD’s, and the effect of fraction size on TCD50 was also evaluated. Due to the advantage of reoxygenation over a course of radiotherapy, conventional fraction sizes (2-2.4 Gy fx-1) were predicted to result in smaller TCD50's than larger fraction sizes (4-5 Gy fx-1) for a 10 cc tumour with GFs of around 0.15. The time to eliminate hypoxic cells (the reoxygenation time) was estimated for a given GF and decreased as GF increased. The extra dose required to overcome accelerated stem cell accumulation in longer treatment schedules was estimated to be 0.68 Gy/day (in EQD26.6), similar to published values derived from clinical data. The model predicts

  4. Adipose stromal cells primed with hypoxia and inflammation enhance cardiomyocyte proliferation rate in vitro through STAT3 and Erk1/2

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    Przybyt Ewa

    2013-02-01

    Full Text Available Abstract Background Experimental clinical stem cell therapy has been used for more than a decade to alleviate the adverse aftermath of acute myocardial infarction (aMI. The post-infarcted myocardial microenvironment is characterized by cardiomyocyte death, caused by ischemia and inflammation. These conditions may negatively affect administered stem cells. As postnatal cardiomyocytes have a poor proliferation rate, while induction of proliferation seems even more rare. Thus stimulation of their proliferation rate is essential after aMI. In metaplastic disease, the pro-inflammatory cytokine interleukin-6 (IL-6 has been identified as potent mediators of the proliferation rate. We hypothesized that IL-6 could augment the proliferation rate of (slow-dividing cardiomyocytes. Methods To mimic the behavior of therapeutic cells in the post-infarct cardiac microenvironment, human Adipose Derived Stromal Cells (ADSC were cultured under hypoxic (2% O2 and pro-inflammatory conditions (IL-1β for 24h. Serum-free conditioned medium from ADSC primed with hypoxia and/or IL-1β was added to rat neonatal cardiomyocytes and adult cardiomyocytes (HL-1 to assess paracrine-driven changes in cardiomyocyte proliferation rate and induction of myogenic signaling pathways. Results We demonstrate that ADSC enhance the proliferation rate of rat neonatal cardiomyocytes and adult HL-1 cardiomyocytes in a paracrine fashion. ADSC under hypoxia and inflammation in vitro had increased the interleukin-6 (IL-6 gene and protein expression. Similar to conditioned medium of ADSC, treatment of rat neonatal cardiomyocytes and HL-1 with recombinant IL-6 alone also stimulated their proliferation rate. This was corroborated by a strong decrease of cardiomyocyte proliferation after addition of IL-6 neutralizing antibody to conditioned medium of ADSC. The stimulatory effect of ADSC conditioned media or IL-6 was accomplished through activation of both Janus Kinase-Signal Transducer and

  5. Cancer cell-associated cytoplasmic B7–H4 is induced by hypoxia through hypoxia-inducible factor-1α and promotes cancer cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, You-Kyoung [Department of Microbiology and Immunology, Inje University College of Medicine, Busan 614-735 (Korea, Republic of); Advanced Research Center for Multiple Myeloma, Inje University College of Medicine, Busan 614-735 (Korea, Republic of); Park, Sae-Gwang; Choi, Il-Whan [Department of Microbiology and Immunology, Inje University College of Medicine, Busan 614-735 (Korea, Republic of); Lee, Soo-Woong [Advanced Research Center for Multiple Myeloma, Inje University College of Medicine, Busan 614-735 (Korea, Republic of); Lee, Sang Min [Department of Internal Medicine, Division of Hematology/Oncology, Busan Paik Hospital, Inje University, Busan 614-735 (Korea, Republic of); Choi, Inhak, E-mail: miccih@inje.ac.kr [Department of Microbiology and Immunology, Inje University College of Medicine, Busan 614-735 (Korea, Republic of); Advanced Research Center for Multiple Myeloma, Inje University College of Medicine, Busan 614-735 (Korea, Republic of)

    2015-04-03

    Aberrant B7–H4 expression in cancer tissues serves as a novel prognostic biomarker for poor survival in patients with cancer. However, the factor(s) that induce cancer cell-associated B7–H4 remain to be fully elucidated. We herein demonstrate that hypoxia upregulates B7–H4 transcription in primary CD138{sup +} multiple myeloma cells and cancer cell lines. In support of this finding, analysis of the Multiple Myeloma Genomics Portal (MMGP) data set revealed a positive correlation between the mRNA expression levels of B7–H4 and the endogenous hypoxia marker carbonic anhydrogenase 9. Hypoxia-induced B7–H4 expression was detected in the cytoplasm, but not in cancer cell membranes. Chromatin immunoprecipitation analysis demonstrated binding of hypoxia-inducible factor-1α (HIF-1α) to proximal hypoxia-response element (HRE) sites within the B7–H4 promoter. Knockdown of HIF-1α and pharmacological inhibition of HIF-1α diminished B7–H4 expression. Furthermore, knockdown of cytoplasmic B7–H4 in MCF-7 decreased the S-phase cell population under hypoxia. Finally, MMGP analysis revealed a positive correlation between the transcript levels of B7–H4 and proliferation-related genes including MKI67, CCNA1, and Myc in several patients with multiple myeloma. Our results provide insight into the mechanisms underlying B7–H4 upregulation and its role in cancer cell proliferation in a hypoxic tumor microenvironment. - Highlights: • Hypoxia upregulates B7–H4 transcription and protein expression. • Hypoxia-induced B7–H4 is detected in the cytoplasm, but not on membrane. • ChIP assay reveals a binding of HIF-1α to B7–H4 promoter at HRE site. • Knockdown and pharmacological inhibition of HIF-1α reduce B7–H4 expression. • B7–H4 knockdown decrease the number of cells in S-phase of cell cycle.

  6. Chronic hypoxia induces the in vivo activation of the Wnt/β-catenin signaling pathway and stimulates hippocampal neurogenesis in wild-type and APPswe-PS1deltaE9 transgenic mice

    Directory of Open Access Journals (Sweden)

    Lorena eVarela-Nallar

    2014-02-01

    Full Text Available Hypoxia modulates proliferation and differentiation of cultured embryonic and adult stem cells, an effect that includes β-catenin a key component of the canonical Wnt signaling pathway. Here we studied in vivo the effect of mild hypoxia on the activity of the Wnt/β-catenin signaling pathway in the hippocampus of adult mice. As a molecular control of the physiological hypoxic response the hypoxia-inducible transcription factor-1α (HIF-1α was analyzed. Exposure to chronic hypoxia (10% oxygen for 6-72 h stimulated the activation of the Wnt/β-catenin signaling pathway. Because the Wnt/β-catenin pathway is a positive modulator of adult neurogenesis, we evaluated whether chronic hypoxia was able to stimulate neurogenesis in the subgranular zone (SGZ of the hippocampal dentate gyrus. Results indicate that hypoxia increased cell proliferation and neurogenesis in adult wild-type mice as determined by Ki67 staining, BrdU incorporation and double labeling with doublecortin. Chronic hypoxia also induced neurogenesis in double transgenic APPswe-PS1deltaE9 mouse model of Alzheimer’s disease (AD, which shows decreased levels of neurogenesis at the SGZ. Our results show for the first time that in vivo exposure to hypoxia can induce the activation of the Wnt/β-catenin signaling cascade in the hippocampus, suggesting that mild hypoxia may have a therapeutic value in neurodegenerative disorder associated with altered Wnt signaling in the brain and also in pathological conditions in which hippocampal neurogenesis is impaired.

  7. Chronic hypoxia induces the activation of the Wnt/β-catenin signaling pathway and stimulates hippocampal neurogenesis in wild-type and APPswe-PS1ΔE9 transgenic mice in vivo

    Science.gov (United States)

    Varela-Nallar, Lorena; Rojas-Abalos, Macarena; Abbott, Ana C.; Moya, Esteban A.; Iturriaga, Rodrigo; Inestrosa, Nibaldo C.

    2014-01-01

    Hypoxia modulates proliferation and differentiation of cultured embryonic and adult stem cells, an effect that includes β-catenin, a key component of the canonical Wnt signaling pathway. Here we studied the effect of mild hypoxia on the activity of the Wnt/β-catenin signaling pathway in the hippocampus of adult mice in vivo. The hypoxia-inducible transcription factor-1α (HIF-1α) was analyzed as a molecular control of the physiological hypoxic response. Exposure to chronic hypoxia (10% oxygen for 6–72 h) stimulated the activation of the Wnt/β-catenin signaling pathway. Because the Wnt/β-catenin pathway is a positive modulator of adult neurogenesis, we evaluated whether chronic hypoxia was able to stimulate neurogenesis in the subgranular zone (SGZ) of the hippocampal dentate gyrus. Results indicate that hypoxia increased cell proliferation and neurogenesis in adult wild-type mice as determined by Ki67 staining, Bromodeoxyuridine (BrdU) incorporation and double labeling with doublecortin (DCX). Chronic hypoxia also induced neurogenesis in a double transgenic APPswe-PS1ΔE9 mouse model of Alzheimer’s disease (AD), which shows decreased levels of neurogenesis in the SGZ. Our results show for the first time that exposure to hypoxia in vivo can induce the activation of the Wnt/β-catenin signaling cascade in the hippocampus, suggesting that mild hypoxia may have a therapeutic value in neurodegenerative disorders associated with altered Wnt signaling in the brain and also in pathological conditions in which hippocampal neurogenesis is impaired. PMID:24574965

  8. Increased cellular hypoxia and reduced proliferation of both normal and leukaemic cells during progression of acute myeloid leukaemia in rats

    DEFF Research Database (Denmark)

    Jensen, P O; Mortensen, B T; Hodgkiss, R J

    2000-01-01

    The microenvironmental changes in the bone marrow, spleen and liver during progression of the transplantable promyelocytic leukaemia in the Brown Norwegian rat (BNML) have been studied. We used flow cytometry to estimate cellular hypoxia and proliferation based on in vivo pulse-labelling with a m......The microenvironmental changes in the bone marrow, spleen and liver during progression of the transplantable promyelocytic leukaemia in the Brown Norwegian rat (BNML) have been studied. We used flow cytometry to estimate cellular hypoxia and proliferation based on in vivo pulse......-labelling with a mixture of 2-nitroimidazole linked to theophylline (NITP) and bromodeoxyuridine (BrdUrd). The leukaemic cells were identified with the RM124 antibody. In rats inoculated with leukaemic cells the fraction of RM124+ cells was significantly increased from day 20 onwards in the spleen and from day 27...

  9. Use of Molecular Imaging Markers of Glycolysis, Hypoxia and Proliferation (18F-FDG, 64Cu-ATSM and 18F-FLT) in a Dog with Fibrosarcoma

    DEFF Research Database (Denmark)

    Zornhagen, Kamilla; Clausen, Malene; Hansen, Anders Elias

    2015-01-01

    Glycolysis, hypoxia, and proliferation are important factors in the tumor microenvironment contributing to treatment-resistant aggressiveness. Imaging these factors using combined functional positron emission tomography and computed tomography can potentially guide diagnosis and management...

  10. Hypoxia-mimetic agents inhibit proliferation and alter the morphology of human umbilical cord-derived mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Zeng Hui-Lan

    2011-08-01

    Full Text Available Abstract Background The therapeutic efficacy of human mesenchymal stem cells (hMSCs for the treatment of hypoxic-ischemic diseases is closely related to level of hypoxia in the damaged tissues. To elucidate the potential therapeutic applications and limitations of hMSCs derived from human umbilical cords, the effects of hypoxia on the morphology and proliferation of hMSCs were analyzed. Results After treatment with DFO and CoCl2, hMSCs were elongated, and adjacent cells were no longer in close contact. In addition, vacuole-like structures were observed within the cytoplasm; the rough endoplasmic reticulum expanded, and expanded ridges were observed in mitochondria. In addition, DFO and CoCl2 treatments for 48 h significantly inhibited hMSCs proliferation in a concentration-dependent manner (P Conclusions The hypoxia-mimetic agents, DFO and CoCl2, alter umbilical cord-derived hMSCs morphology and inhibit their proliferation through influencing the cell cycle.

  11. Uncaria tomentosa stimulates the proliferation of myeloid progenitor cells.

    Science.gov (United States)

    Farias, Iria; do Carmo Araújo, Maria; Zimmermann, Estevan Sonego; Dalmora, Sergio Luiz; Benedetti, Aloisio Luiz; Alvarez-Silva, Marcio; Asbahr, Ana Carolina Cavazzin; Bertol, Gustavo; Farias, Júlia; Schetinger, Maria Rosa Chitolina

    2011-09-01

    The Asháninkas, indigenous people of Peru, use cat's claw (Uncaria tomentosa) to restore health. Uncaria tomentosa has antioxidant activity and works as an agent to repair DNA damage. It causes different effects on cell proliferation depending on the cell type involved; specifically, it can stimulate the proliferation of myeloid progenitors and cause apoptosis of neoplastic cells. Neutropenia is the most common collateral effect of chemotherapy. For patients undergoing cancer treatment, the administration of a drug that stimulates the proliferation of healthy hematopoietic tissue cells is very desirable. It is important to assess the acute effects of Uncaria tomentosa on granulocyte-macrophage colony-forming cells (CFU-GM) and in the recovery of neutrophils after chemotherapy-induced neutropenia, by establishing the correlation with filgrastim (rhG-CSF) treatment to evaluate its possible use in clinical oncology. The in vivo assay was performed in ifosfamide-treated mice receiving oral doses of 5 and 15 mg of Uncaria tomentosa and intraperitoneal doses of 3 and 9 μg of filgrastim, respectively, for four days. Colony-forming cell (CFC) assays were performed with human hematopoietic stem/precursor cells (hHSPCs) obtained from umbilical cord blood (UCB). Bioassays showed that treatment with Uncaria tomentosa significantly increased the neutrophil count, and a potency of 85.2% was calculated in relation to filgrastim at the corresponding doses tested. An in vitro CFC assay showed an increase in CFU-GM size and mixed colonies (CFU-GEMM) size at the final concentrations of 100 and 200 μg extract/mL. At the tested doses, Uncaria tomentosa had a positive effect on myeloid progenitor number and is promising for use with chemotherapy to minimize the adverse effects of this treatment. These results support the belief of the Asháninkas, who have classified Uncaria tomentosa as a 'powerful plant'. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  12. HIF-1α activation by intermittent hypoxia requires NADPH oxidase stimulation by xanthine oxidase.

    Science.gov (United States)

    Nanduri, Jayasri; Vaddi, Damodara Reddy; Khan, Shakil A; Wang, Ning; Makarenko, Vladislav; Semenza, Gregg L; Prabhakar, Nanduri R

    2015-01-01

    Hypoxia-inducible factor 1 (HIF-1) mediates many of the systemic and cellular responses to intermittent hypoxia (IH), which is an experimental model that simulates O2 saturation profiles occurring with recurrent apnea. IH-evoked HIF-1α synthesis and stability are due to increased reactive oxygen species (ROS) generated by NADPH oxidases, especially Nox2. However, the mechanisms by which IH activates Nox2 are not known. We recently reported that IH activates xanthine oxidase (XO) and the resulting increase in ROS elevates intracellular calcium levels. Since Nox2 activation requires increased intracellular calcium levels, we hypothesized XO-mediated calcium signaling contributes to Nox activation by IH. We tested this possibility in rat pheochromocytoma PC12 cells subjected to IH consisting alternating cycles of hypoxia (1.5% O2 for 30 sec) and normoxia (21% O2 for 5 min). Kinetic analysis revealed that IH-induced XO preceded Nox activation. Inhibition of XO activity either by allopurinol or by siRNA prevented IH-induced Nox activation, translocation of the cytosolic subunits p47phox and p67phox to the plasma membrane and their interaction with gp91phox. ROS generated by XO also contribute to IH-evoked Nox activation via calcium-dependent protein kinase C stimulation. More importantly, silencing XO blocked IH-induced upregulation of HIF-1α demonstrating that HIF-1α activation by IH requires Nox2 activation by XO.

  13. Inhibition of P-glycoprotein stimulates cell death under Hypoxia-mimicking conditions.

    Science.gov (United States)

    Vdovin, A S; Maximchik, P V; Kulikov, A V; Zhivotovsky, B D; Gogvadze, V G

    2017-01-01

    The most common drug resistance mechanism in tumor cells is expression on their surface of the energy-dependent pump like P-glycoprotein (P-gp) that expels chemotherapeutic agents from the interior. An imitation of the hypoxic condition by the iron chelator deferoxamine caused Hypoxia-inducible factor 1-alpha (HIF-1α) stabilization and inhibition of doxorubicin-induced apoptosis in colon cancer НСТ116 cells. P-gp blocker verapamil suppressed doxorubicin accumulation leading to cell death induction. Considering these results, P-gp may be used as a potential target to stimulate chemotherapeutic drugs activity that will contribute to more efficient tumor cells elimination.

  14. The effect of hypoxia on PGE2-stimulated cAMP generation in HMEC-1.

    Science.gov (United States)

    Wiktorowska-Owczarek, Anna; Owczarek, Jacek

    2015-06-01

    Prostaglandin E2 (PGE2) is generated in various cells, including endothelial cells, and is responsible for various functions, such as vascular relaxation and angiogenesis. Effects of PGE2 are mediated via receptors EP1-EP4, among which EP2 and EP4 are coupled to Gs protein which activates adenylate cyclase (AC) and cAMP synthesis. The aim of this work was to study the ability of human microvascular endothelial cells (HMEC-1) to synthesize cAMP in the presence of PGE2, and to determine the effect of hypoxia on the PGE2- stimulated cAMP level. It was decided to evaluate the effect of PGE2 on the secretion of VEGF, an inducer of angiogenesis. In summary, our findings show that PGE2 induces cAMP production, but hypoxia may impair PGE2-stimulated activity of the AC-cAMP signaling pathway. These results suggest that the cardioprotective effect of PGE2/EP4/cAMP may be attenuated during ischemia. Furthermore, this study indicates that the pro-angiogenic effect of PGE2 is not associated with VEGF secretion in HMEC-1 cells.

  15. Newborn hypoxia/anoxia inhibits cardiomyocyte proliferation and decreases cardiomyocyte endowment in the developing heart: role of endothelin-1.

    Directory of Open Access Journals (Sweden)

    Alexandra N Paradis

    Full Text Available In the developing heart, cardiomyocytes undergo terminal differentiation during a critical window around birth. Hypoxia is a major stress to preterm infants, yet its effect on the development and maturation of the heart remains unknown. We tested the hypothesis in a rat model that newborn anoxia accelerates cardiomyocyte terminal differentiation and results in reduced cardiomyocyte endowment in the developing heart via an endothelin-1-dependent mechanism. Newborn rats were exposed to anoxia twice daily from postnatal day 1 to 3, and hearts were isolated and studied at postnatal day 4 (P4, 7 (P7, and 14 (P14. Anoxia significantly increased HIF-1α protein expression and pre-proET-1 mRNA abundance in P4 neonatal hearts. Cardiomyocyte proliferation was significantly decreased by anoxia in P4 and P7, resulting in a significant reduction of cardiomyocyte number per heart weight in the P14 neonates. Furthermore, the expression of cyclin D2 was significantly decreased due to anoxia, while p27 expression was increased. Anoxia has no significant effect on cardiomyocyte binucleation or myocyte size. Consistently, prenatal hypoxia significantly decreased cardiomyocyte proliferation but had no effect on binucleation in the fetal heart. Newborn administration of PD156707, an ETA-receptor antagonist, significantly increased cardiomyocyte proliferation at P4 and cell size at P7, resulting in an increase in the heart to body weight ratio in P7 neonates. In addition, PD156707 abrogated the anoxia-mediated effects. The results suggest that hypoxia and anoxia via activation of endothelin-1 at the critical window of heart development inhibits cardiomyocyte proliferation and decreases myocyte endowment in the developing heart, which may negatively impact cardiac function later in life.

  16. Effects of hypoxia on the expression of CCR7 and proliferation, invasiveness of A549 cells

    Directory of Open Access Journals (Sweden)

    Yang LI

    2008-10-01

    Full Text Available Background and objective It has been proven that hypoxia could promote tumor cells invasion and metastasis by different mechanisms, but the relationship between hypoxia and CCR7 have not been reported. The aim of this investigate is to evaluate the effects of hypoxia on the expression of CCR7 and the invasiveness of lung adenocarcinoma A549 cells. Methods A549 cells were incubated at either normoxia (37 ℃, 5%CO2, 21%O2 or hypoxia(37 ℃, 5%CO2, 1%O2 condition for 4 h,12 h, 24 h. The expressions of CCR7 mRNA and protein levels were observed by RT-PCR and Western blotting; Cells invasiveness was measured by matrigel invasion assay. Results RT-PCR and Western blotting showed that the expression of CCR7 was detected in lung adenocarcinoma A549 cells, CCR7 mRNA and protein expression level were increased with culture time along either in normoxia or hypoxia condition; Furthermore,compared with normoxia group, the CCR7 mRNA and protein expression level in hypoxia group was increased (P <0.01.The results of Transwell invasion showed that The number of invasive cells was significantly increased in hypoxia group(t =0.006, P <0.01 and A549 cells invasive ability was inhibited after add anti-CCR7 Ab to culture medium (t =0.09, P <0.01. Conclusion The results suggest that hypoxia plays an important role in the augmentation of the CCR7 expression and invasiveness of A549 cells. Invasion of A549 cells in hypoxia condition correlated with CCR7 expression level.

  17. ROCK2 mediates the proliferation of pulmonary arterial endothelial cells induced by hypoxia in the development of pulmonary arterial hypertension

    OpenAIRE

    Qiao, Feng; ZOU, ZHITIAN; Liu, Chunhui; Zhu, Xiaofeng; Wang, Xiaoqiang; YANG, CHENGPENG; JIANG, TENGJIAO; Chen, Ying

    2016-01-01

    It has been reported that RhoA activation and Rho-kinase (ROCK) expression are increased in chronic hypoxic lungs, and the long-term inhibition of ROCK markedly improves the survival of patients with pulmonary arterial hypertension (PAH). However, whether Rho-kinase α (ROCK2) participates in regulation of the growth of pulmonary arterial endothelial cells (PAECs) remains unknown. The aim of the present study was to investigate the effect of hypoxia on the proliferation of PAECs and the role o...

  18. ROCK2 mediates the proliferation of pulmonary arterial endothelial cells induced by hypoxia in the development of pulmonary arterial hypertension

    OpenAIRE

    Qiao, Feng; ZOU, ZHITIAN; Liu, Chunhui; Zhu, Xiaofeng; Wang, Xiaoqiang; YANG, CHENGPENG; JIANG, TENGJIAO; Chen, Ying

    2016-01-01

    It has been reported that RhoA activation and Rho-kinase (ROCK) expression are increased in chronic hypoxic lungs, and the long-term inhibition of ROCK markedly improves the survival of patients with pulmonary arterial hypertension (PAH). However, whether Rho-kinase α (ROCK2) participates in regulation of the growth of pulmonary arterial endothelial cells (PAECs) remains unknown. The aim of the present study was to investigate the effect of hypoxia on the proliferation of PAECs and the role o...

  19. Expression of Hypoxia Inducible Factor-1α and Its Relationship to Apoptosis and Proliferation in Human Laryngeal Squamous Cell Carcinoma

    Institute of Scientific and Technical Information of China (English)

    俞琳琳; 刘洋; 崔永华

    2004-01-01

    To investigate the expression of hypoxia inducible factor-1 alpha (HIF-1α) and its relationship to apoptosis and proliferation in laryngeal squamous cell carcinoma (LSCC), immunohistochemical method was used to detect the expression of HIF-1α and PCNA. Tunnel technique was used to detect in situ cell apoptosis in LSCC. Our results showed that the expression of HIF-1α was related to the clinical stages of cancer and lymph node metastasis (P<0. 05). The relationship between HIF-1α and PCNA was statistically significant (P<0.05) and no relationship was found between HIF-1α and apoptosis (P>0.05) It is concluded that HIF-1α plays a role in the carcinogenesis of laryngeal carcinoma and is correlated with proliferation, but bears no relationship with the apoptosis of tumor cells in LSCC.

  20. Hypoxia and prostaglandin E receptor 4 signalling pathways synergise to promote endometrial adenocarcinoma cell proliferation and tumour growth.

    Directory of Open Access Journals (Sweden)

    Rob D Catalano

    Full Text Available The prostaglandin endoperoxide synthase (PTGS pathway is a potent driver of tumour development in humans by enhancing the biosynthesis and signalling of prostaglandin (PG E(2. PTGS2 expression and PGE(2 biosynthesis is elevated in endometrial adenocarcinoma, however the mechanism whereby PTGS and PGE(2 regulate endometrial tumour growth is unknown. Here we investigated (a the expression profile of the PGE synthase enzymes (PTGES, PTGES-2, PTGES-3 and PGE receptors (PTGER1-4 in endometrial adenocarcinomas compared with normal endometrium and (b the role of PTGER4 in endometrial tumorigenesis in vivo. We found elevated expression of PTGES2 and PTGER4 and suppression of PTGER1 and PTGER3 in endometrial adenocarcinomas compared with normal endometrium. Using WT Ishikawa endometrial adenocarcinoma cells and Ishikawa cells stably transfected with the full length PTGER4 cDNA (PTGER4 cells xenografted in the dorsal flanks of nude mice, we show that PTGER4 rapidly and significantly enhances tumour growth rate. Coincident with enhanced PTGER4-mediated tumour growth we found elevated expression of PTGS2 in PTGER4 xenografts compared with WT xenografts. Furthermore we found that the augmented growth rate of the PTGER4 xenografts was not due to enhanced angiogenesis, but regulated by an increased proliferation index and hypoxia. In vitro, we found that PGE(2 and hypoxia independently induce expression of PTGER4 indicating two independent pathways regulating prostanoid receptor expression. Finally we have shown that PGE(2 and hypoxia synergise to promote cellular proliferation of endometrial adenocarcinoma cells.

  1. Ginsenosides stimulated the proliferation of mouse spermatogonia involving activation of protein kinase C

    Institute of Scientific and Technical Information of China (English)

    Da-lei ZHANG; Kai-ming WANG; Cai-qiao ZHANG

    2009-01-01

    The effect of ginsenosides on proliferation of type A spermatogonia was investigated in 7-day-old mice.Spermatogonia were characterized by c-kit expression and cell proliferation was assessed by immunocytochemical demonstration of proliferating cell nuclear antigen (PCNA).After 72-h culture,Sertoli cells formed a confluent monolayer to which numerous spermatogonial colonies attached.Spermatogonia were positive for c-kit staining and showed high proliferating activity by PCNA expression.Ginsenosides (1.0~10 μg/ml) significantly stimulated proliferation of spermatogonia.Activation of protein kinase C (PKC) elicited proliferation of spermatogonia at 10-8 to 107 mol/L and the PKC inhibitor H7 inhibited this effect.Likewise,ginsenosides-stimulated spermatogonial proliferation was suppressed by combined treatment of H7.These results indicate that the proliferating effect ofginsenosides on mouse type A spermatogonia might be mediated by a mechanism involving the PKC signal transduction pathway.

  2. Micro Regional Heterogeneity of 64Cu-ATSM and 18F-FDG Uptake in Canine Soft Tissue Sarcomas: Relation to Cell Proliferation, Hypoxia and Glycolysis

    Science.gov (United States)

    Zornhagen, Kamilla Westarp; Hansen, Anders E.; Oxboel, Jytte; Clemmensen, Andreas E.; El Ali, Henrik H.; Kristensen, Annemarie T.; Kjær, Andreas

    2015-01-01

    Objectives Tumour microenvironment heterogeneity is believed to play a key role in cancer progression and therapy resistance. However, little is known about micro regional distribution of hypoxia, glycolysis and proliferation in spontaneous solid tumours. The overall aim was simultaneous investigation of micro regional heterogeneity of 64Cu-ATSM (hypoxia) and 18F-FDG (glycolysis) uptake and correlation to endogenous markers of hypoxia, glycolysis, proliferation and angiogenesis to better therapeutically target aggressive tumour regions and prognosticate outcome. Methods Exploiting the different half-lives of 64Cu-ATSM (13h) and 18F-FDG (2h) enabled simultaneous investigation of micro regional distribution of hypoxia and glycolysis in 145 tumour pieces from four spontaneous canine soft tissue sarcomas. Pairwise measurements of radioactivity and gene expression of endogenous markers of hypoxia (HIF-1α, CAIX), glycolysis (HK2, GLUT1 and GLUT3), proliferation (Ki-67) and angiogenesis (VEGFA and TF) were performed. Dual tracer autoradiography was compared with Ki-67 immunohistochemistry. Results Micro regional heterogeneity in hypoxia and glycolysis within and between tumour sections of each tumour piece was observed. The spatial distribution of 64Cu-ATSM and 18F-FDG was rather similar within each tumour section as reflected in moderate positive significant correlations between the two tracers (ρ = 0.3920–0.7807; p = 0.0180 –Micro regional heterogeneity of hypoxia and glycolysis was documented in spontaneous canine soft tissue sarcomas. 64Cu-ATSM and 18F-FDG uptakes and distributions showed significant moderate correlations at the micro regional level indicating overlapping, yet different information from the tracers.18F-FDG better reflected cell proliferation as measured by Ki-67 gene expression than 64Cu-ATSM. PMID:26501874

  3. Autocrine stimulation of clear-cell renal carcinoma cell migration in hypoxia via HIF-independent suppression of thrombospondin-1

    Science.gov (United States)

    Bienes-Martínez, Raquel; Ordóñez, Angel; Feijoo-Cuaresma, Mónica; Corral-Escariz, María; Mateo, Gloria; Stenina, Olga; Jiménez, Benilde; Calzada, María J.

    2012-01-01

    Thrombospondin-1 is a matricellular protein with potent antitumour activities, the levels of which determine the fate of many different tumours, including renal carcinomas. However, the factors that regulate this protein remain unclear. In renal carcinomas, hypoxic conditions enhance the expression of angiogenic factors that help adapt tumour cells to their hostile environment. Therefore, we hypothesized that anti-angiogenic factors should correspondingly be dampened. Indeed, we found that hypoxia decreased the thrombospondin-1 protein in several clear cell renal carcinoma cell lines (ccRCC), although no transcriptional regulation was observed. Furthermore, we proved that hypoxia stimulates multiple signals that independently contribute to diminish thrombospondin-1 in ccRCC, which include a decrease in the activity of oxygen-dependent prolylhydroxylases (PHDs) and activation of the PI3K/Akt signalling pathway. In addition, thrombospondin-1 regulation in hypoxia proved to be important for ccRCC cell migration and invasion. PMID:23145312

  4. Insulin-Like Growth Factor Receptor Signaling is Necessary for Epidermal Growth Factor Mediated Proliferation of SVZ Neural Precursors Following Neonatal Hypoxia-Ischemia

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    Dhivyaa eAlagappan

    2014-05-01

    Full Text Available In this study we assessed the importance of insulin-like growth factor (IGF and epidermal growth factor (EGF receptor co-signaling for rat neural precursor (NP cell proliferation and self-renewal in the context of a developmental brain injury that is associated with cerebral palsy. Consistent with previous studies, we found that there is an increase in the in vitro growth of subventricular zone (SVZ NPs isolated acutely after cerebral hypoxia-ischemia; however, when cultured in medium that is insufficient to stimulate the IGF type 1 receptor, neurosphere formation and the proliferative capacity of those NPs was severely curtailed. This reduced growth capacity could not be attributed simply to failure to survive. The growth and self-renewal of the NPs could be restored by addition of both IGF-I and IGF-II. Since the size of the neurosphere is predominantly due to cell proliferation we hypothesized that the IGFs were regulating progression through the cell cycle. Analyses of cell cycle progression revealed that IGF-1R activation together with EGFR co-signaling decreased the percentage of cells in G1 and enhanced cell progression into S and G2. This was accompanied by increases in expression of cyclin D1, phosphorylated histone 3 and phosphorylated Rb. Based on these data we conclude that coordinate signaling between the EGF receptor and the IGF type 1 receptor is necessary for the normal proliferation of NPs as well as for their reactive expansion after injury. These data indicate that manipulations that maintain or amplify IGF signaling in the brain during recovery from developmental brain injuries will enhance the production of new brain cells to improve neurological function in children who are at risk for developing cerebral palsy.

  5. Baicalin Inhibits Hypoxia-Induced Pulmonary Artery Smooth Muscle Cell Proliferation via the AKT/HIF-1α/p27-Associated Pathway

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    Lin Zhang

    2014-05-01

    Full Text Available Baicalin, a flavonoid compound purified from the dry roots of Scutellaria baicalensis Georgi, has been shown to possess various pharmacological actions. Previous studies have revealed that baicalin inhibits the growth of cancer cells through the induction of apoptosis. Pulmonary arterial hypertension (PAH is a devastating disease characterized by enhanced pulmonary artery smooth muscle cell (PASMCs proliferation and suppressed apoptosis. However, the potential mechanism of baicalin in the regulation of PASMC proliferation and the prevention of cardiovascular diseases remains unexplored. To test the effects of baicalin on hypoxia, we used rats treated with or without baicalin (100 mg·kg−1 each rat at the beginning of the third week after hypoxia. Hemodynamic and pulmonary pathomorphology data showed that right ventricular systolic pressures (RVSP, the weight of the right ventricle/left ventricle plus septum (RV/LV + S ratio and the medial width of pulmonary arterioles were much higher in chronic hypoxia. However, baicalin treatment repressed the elevation of RVSP, RV/LV + S and attenuated the pulmonary vascular structure remodeling (PVSR of pulmonary arterioles induced by chronic hypoxia. Additionally, baicalin (10 and 20 μmol·L−1 treatment suppressed the proliferation of PASMCs and attenuated the expression of hypoxia-inducible factor-α (HIF-α under hypoxia exposure. Meanwhile, baicalin reversed the hypoxia-induced reduction of p27 and increased AKT/protein kinase B phosphorylation p-AKT both in vivo and in vitro. These results suggested that baicalin could effectively attenuate PVSR and hypoxic pulmonary hypertension.

  6. Hypoxia-inducible factor-1α increased the expression of peroxisome proliferator activated receptor α in lung cancer cell A549

    Institute of Scientific and Technical Information of China (English)

    张惠兰; 张珍祥; 徐永健

    2004-01-01

    @@ Hypoxia plays a fundamental role in many pathologic processes. Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric basic helix-loop-helix-per-aryl hydrocarbon receptor ARNT-sim (PAS) domain protein, consisting of α and β subunits and is precisely regulated by cellular oxygen levels.1 The peroxisome proliferator-activated receptors (PPARs) are family nuclear hormone-binding proteins with increasing diverse functions as transcriptional regulators, owning three subtypes (α, β, and γ).2 PPARα plays a critical physiological role as lipid sensors and regulators of proliferation.3 Hypoxia can elicit up-regulation of PPAR-α expression.4 Herein, we report the results of an investigation on the correlation of HIF-1α and PPARα.

  7. Increased cellular hypoxia and reduced proliferation of both normal and leukaemic cells during progression of acute myeloid leukaemia in rats

    DEFF Research Database (Denmark)

    Jensen, P O; Mortensen, B T; Hodgkiss, R J;

    2000-01-01

    The microenvironmental changes in the bone marrow, spleen and liver during progression of the transplantable promyelocytic leukaemia in the Brown Norwegian rat (BNML) have been studied. We used flow cytometry to estimate cellular hypoxia and proliferation based on in vivo pulse...... in the bone marrow and liver, reaching a level of 65-87% in these organs at day 32. At day 32, the NITP+ fraction of RM124+ cells had increased significantly in the bone marrow and spleen to 88% and 90%, respectively. The corresponding fractions of NITP+ normal cells reached 63% and 65%, respectively. From......-labelling with a mixture of 2-nitroimidazole linked to theophylline (NITP) and bromodeoxyuridine (BrdUrd). The leukaemic cells were identified with the RM124 antibody. In rats inoculated with leukaemic cells the fraction of RM124+ cells was significantly increased from day 20 onwards in the spleen and from day 27...

  8. Overexpression of FABP3 inhibits human bone marrow derived mesenchymal stem cell proliferation but enhances their survival in hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Suna, E-mail: wangs3@mail.nih.gov; Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-04-15

    Studying the proliferative ability of human bone marrow derived mesenchymal stem cells in hypoxic conditions can help us achieve the effective regeneration of ischemic injured myocardium. Cardiac-type fatty acid binding protein (FABP3) is a specific biomarker of muscle and heart tissue injury. This protein is purported to be involved in early myocardial development, adult myocardial tissue repair and responsible for the modulation of cell growth and proliferation. We have investigated the role of FABP3 in human bone marrow derived mesenchymal stem cells under ischemic conditions. MSCs from 12 donors were cultured either in standard normoxic or modified hypoxic conditions, and the differential expression of FABP3 was tested by quantitative {sup RT}PCR and western blot. We also established stable FABP3 expression in MSCs and searched for variation in cellular proliferation and differentiation bioprocesses affected by hypoxic conditions. We identified: (1) the FABP3 differential expression pattern in the MSCs under hypoxic conditions; (2) over-expression of FABP3 inhibited the growth and proliferation of the MSCs; however, improved their survival in low oxygen environments; (3) the cell growth factors and positive cell cycle regulation genes, such as PCNA, APC, CCNB1, CCNB2 and CDC6 were all down-regulated; while the key negative cell cycle regulation genes TP53, BRCA1, CASP3 and CDKN1A were significantly up-regulated in the cells with FABP3 overexpression. Our data suggested that FABP3 was up-regulated under hypoxia; also negatively regulated the cell metabolic process and the mitotic cell cycle. Overexpression of FABP3 inhibited cell growth and proliferation via negative regulation of the cell cycle and down-regulation of cell growth factors, but enhances cell survival in hypoxic or ischemic conditions. - Highlights: • FABP3 expression pattern was studied in 12 human hypoxic-MSCs. • FABP3 mRNA and proteins are upregulated in the MSCs under hypoxic conditions.

  9. Suppression of the proliferation of hypoxia-Induced retinal pigment epithelial cell by rapamycin through the /mTOR/HIF-1α/VEGF/ signaling.

    Science.gov (United States)

    Liu, Ning-Ning; Zhao, Ning; Cai, Na

    2015-06-01

    Rapamycin, a highly specific inhibitor of mammalian target of rapamycin (mTOR), exhibits significant antitumor/antiangiogenic activity in human cancer cells. Its effect on the retinal pigment epithelial (RPE) cells was rarely investigated. This study assessed the proliferation of hypoxia-induced RPE and the inhibitory effects of rapamycin using 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and examined the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in RPE cells with or without rapamycin under normoxic and hypoxic conditions using real-time PCR and Western blot. We found that hypoxia increased the levels of mTOR, HIF-1α, and VEGF. The suppression of HIF-1α and VEGF by rapamycin was associated with dephosphorylation of mTOR and the downstream effector ribosomal protein S6 kinase (P70S6K) and 4E-binding protein-1 (4E-BP1) of mTORC1. Rapamycin only inhibited the protein levels and did not change the mRNA expression of HIF-1α. No cytotoxicity to the RPE cells by rapamycin was caused under either normoxia or hypoxia. Our data suggest that rapamycin suppresses hypoxia-induced RPE cell proliferation through a mechanism related to the targeting of mTOR/HIF-1α/VEGF signaling. Rapamycin may potentially provide a safe and effective novel treatment for choroidal vascular disease.

  10. Effects of low dose oxymatrine on mouse lymphocyte proliferation stimulated by Con A

    Institute of Scientific and Technical Information of China (English)

    LI Luo-si; WU Bin; LI Jian-guo; XIE Hong-fu; ZHANG Yang-de; CONG Ling; SHI Jun

    2005-01-01

    Objective To investigate the effects of low dose Oxymatrine (OMT) on mouse lymphocyte proliferation stimulated by Con A making use of fluorescence dyestuff CFDA-SE. Methods CFDA-SE staining and flow cytometry were used to detect the fluorescence intensity of lymphocytes after stimulated by polyclonal stimulators Con A and OMT. Then, related software was used to analyze the effects of OMT on mouse lymphocyte proliferation.Results After cultured for 48 h, CFSE fluorescence could be detected by cytometer, filial generation peaks did not appear in control group, which indicated that lymphocytes did not proliferate. Three peaks were obviously detected in Con A group which indicated that Lymphocytes divided after 48 h stimulated by Con A compared with the halving of the fluorescence intensity of control group. In groups with Con A and OMT treated, Primary generation peaks are all lower while filial generation peaks are significantly higher than groups with Con A treated only. This indicated OMT obviously promote lymphocyte proliferation. After cultured for 72 h, the fluorescence intensity changes between all groups are consistent with those of cultured for 48 h. Analyzed with CELLQuest software, it is shown that OMT could promote lymphocyte proliferation in 16, 8, 4 and 2μg/mL respectively. Conclusions 1) CFDA-SEdyeing and flow cytometer were both reliable tools to analyze lymphocyte proliferation; 2) lower dosage of OMTcould promote the proliferation of lymphocyte as a immunopotentiator.

  11. Stimulation of Cellular Proliferation by Hepatitis B Virus X Protein

    Directory of Open Access Journals (Sweden)

    Charles R. Madden

    2001-01-01

    Full Text Available Chronic infection with the hepatitis B virus (HBV is a known risk factor in the development of human hepatocellular carcinoma (HCC. The HBV-encoded X protein, HBx, has been investigated for properties that may explain its cancer cofactor role in transgenic mouse lines. We discuss here recent data showing that HBx is able to induce hepatocellular proliferation in vitro and in vivo. This property of HBx is predicted to sensitize hepatocytes to other HCC cofactors, including exposure to carcinogens and to other hepatitis viruses. Cellular proliferation is intimately linked to the mechanism(s by which most tumor-associated viruses transform virus-infected cells. The HBx alteration of the cell cycle provides an additional mechanism by which chronic HBV infection may contribute to HCC.

  12. Gymnemic Acid Stimulates In Vitro Splenic Lymphocyte Proliferation.

    Science.gov (United States)

    Singh, Vineet Kumar; Dwivedi, Padmanabh; Chaudhary, B R; Singh, Ramesh

    2016-02-01

    Gymnemic acid is a mixture of triterpenoid saponins of oleanane class, isolated from Gymnema sylvestre Wild R.Br (family: Asclepidaceae), an herbal plant used in traditional medicine to treat diabetes. Effect of gymnemic acid (0.1-20 µg/mL) on in vitro mitogen (concanavalin A and lipopolysaccharide)-induced splenic lymphocyte proliferation was studied using rat as model. Significant (p sylvestre is scientifically supplemented with its immunomodulatory properties.

  13. Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kyotani, Yoji, E-mail: cd147@naramed-u.ac.jp [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Ota, Hiroyo [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Takasawa, Shin [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Kimura, Hiroshi [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Uno, Masayuki [Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Yoshizumi, Masanori [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan)

    2013-11-15

    Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

  14. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Robert T. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); O' Brien, Fergal J. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Hoey, David A., E-mail: david.hoey@ul.ie [Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); The Centre for Applied Biomedical Engineering Research, University of Limerick (Ireland); Materials & Surface Science Institute, University of Limerick (Ireland)

    2015-03-27

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. - Highlights: • Physically stimulated osteocytes secrete factors that regulate osteoprogenitors. • These factors enhance recruitment, proliferation and osteogenic differentiation. • Physically stimulated osteoblasts secrete factors that also regulate progenitors. • These factors enhance recruitment but inhibit proliferation of osteoprogenitors. • This study highlights a contrasting

  15. HYPOXIA AND ENDOTHELIN-1 STIMULATE DNA SYNTHESIS OF PULMONARY ARTERY SMOOTH MUSCLE CELLS

    Institute of Scientific and Technical Information of China (English)

    冯晓东; 蔡英年

    1996-01-01

    Hypoxia and endothelin-1 (ET-1) are associated with constriction of pulmonary vasculature both in vivo and in vitro. However, the role of hypoxia and ET-1 in the vascular remodelling during the development of pulmonary, hypertension is unciear. This study demonstrated that ET-1 (0.1nmol/L to 100nmol./L)increased the 3H]thymldine uptake in a dose-dependent manner in cuhured bovine pulmonary artery smooth muscle cells(PASMC), which was enhanced by exposing PASMC to hypoxia (2% O2, 93%N2,5%CO2). BQ123, the specific antagonist of endot helin receptor subtype A, eiLmLnated the ET-1 medicated proliferati0n of PASMC and the cooperative effect of hypoxia. Some dilatory drugs could inhibite the mitogenic effect of ET-1. We also observed that hypoxia significantiy increased [3H]thymldine uptake in PASMC without ET-1 and BQ123 could inhibite this effect. Radioimmunoassay suggested that there was an autocrine of ET-1 in cultured PASMC which was enhanced by hypoxia significantly.

  16. Inhibition of tubular cell proliferation by neutralizing endogenous HGF leads to renal hypoxia and bone marrow-derived cell engraftment in acute renal failure.

    Science.gov (United States)

    Ohnishi, Hiroyuki; Mizuno, Shinya; Nakamura, Toshikazu

    2008-02-01

    During the progression of acute renal failure (ARF), the renal tubular S3 segment is sensitive to ischemic stresses. For reversing tubular damage, resident tubular cells proliferate, and bone marrow-derived cells (BMDC) can be engrafted into injured tubules. However, how resident epithelium or BMDC are involved in tubular repair remains unknown. Using a mouse model of ARF, we examined whether hepatocyte growth factor (HGF) regulates a balance of resident cell proliferation and BMDC recruitment. Within 48 h post-renal ischemia, tubular destruction became evident, followed by two-waved regenerative events: 1) tubular cell proliferation between 2 and 4 days, along with an increase in blood HGF; and 2) appearance of BMDC in the tubules from 6 days postischemia. When anti-HGF IgG was injected in the earlier stage, tubular cell proliferation was inhibited, leading to an increase in BMDC in renal tubules. Under the HGF-neutralized state, stromal cell-derived factor-1 (SDF1) levels increased in renal tubules, associated with the enhanced hypoxia. Administrations of anti-SDF1 receptor IgG into ARF mice reduced the number of BMDC in interstitium and tubules. Thus possible cascades include 1) inhibition of tubular cell proliferation by neutralizing HGF leads to renal hypoxia and SDF1 upregulation; and 2) BMDC are eventually engrafted in tubules through SDF1-mediated chemotaxis. Inversely, administration of recombinant HGF suppressed the renal hypoxia, SDF1 upregulation, and BMDC engraftment in ARF mice by enhancing resident tubular cell proliferation. Thus we conclude that HGF is a positive regulator for eliciting resident tubular cell proliferation, and SDF1 for BMDC engraftment during the repair process of ARF.

  17. Role of PKC isozymes in low-power light-stimulated proliferation of cultured skin cells

    Science.gov (United States)

    Grossman, Nili; Kleitman, Vered; Meller, Julia; Kaufmann, Roland; Akgun, Nermin; Ruck, Angelika; Livneh, Etta; Lubart, Rachel

    2000-11-01

    Exposure of cultured skin cells to low power visible light leads to a transiently stimulated proliferation. Facilitation of this response requires the presence of active PKC, elevation of intracellular calcium, and involves reactive oxygen species. In the present study, the role of PKC(alpha) and PCK(eta) was examined using paired murine fibroblasts, differing in the level of these isozymes expression. The ability of the cells to respond to low power UVA light or HeNe laser by stimulated proliferation was correlated with an active state or overexpression of PKC(alpha) , but not PKC(eta) . A parallel response was obtained in cells that were loaded with A1PcS4 before photosensitization. Whenever this latter treatment caused a light-stimulated inhibition, it was accompanied by the intracellular calcium and photosensitizer dynamics typical of the effect of PDT on rate epithelial cells. Accordingly, added antioxidants that suppressed light-stimulated proliferation also suppressed this light-stimulated inhibition. The model systems employed in this study are the first to demonstrate the specific effect of PKC isozymes on light-stimulated proliferation, in relation to oxidative stress, and indicate their dual role in light-tissue interaction.

  18. PDGF is required for remyelination-promoting IgM stimulation of oligodendrocyte progenitor cell proliferation.

    Directory of Open Access Journals (Sweden)

    Jens O Watzlawik

    Full Text Available BACKGROUND: Promotion of remyelination is a major goal in treating demyelinating diseases such as multiple sclerosis (MS. The recombinant human monoclonal IgM, rHIgM22, targets myelin and oligodendrocytes (OLs and promotes remyelination in animal models of MS. It is unclear whether rHIgM22-mediated stimulation of lesion repair is due to promotion of oligodendrocyte progenitor cell (OPC proliferation and survival, OPC differentiation into myelinating OLs or protection of mature OLs. It is also unknown whether astrocytes or microglia play a functional role in IgM-mediated lesion repair. METHODS: We assessed the effect of rHIgM22 on cell proliferation in mixed CNS glial and OPC cultures by tritiated-thymidine uptake and by double-label immunocytochemistry using the proliferation marker, Ki-67. Antibody-mediated signaling events, OPC differentiation and OPC survival were investigated and quantified by Western blots. RESULTS: rHIgM22 stimulates OPC proliferation in mixed glial cultures but not in purified OPCs. There is no proliferative response in astrocytes or microglia. rHIgM22 activates PDGFαR in OPCs in mixed glial cultures. Blocking PDGFR-kinase inhibits rHIgM22-mediated OPC proliferation in mixed glia. We confirm in isolated OPCs that rHIgM22-mediated anti-apoptotic signaling and inhibition of OPC differentiation requires PDGF and FGF-2. We observed no IgM-mediated effect in mature OLs in the absence of PDGF and FGF-2. CONCLUSION: Stimulation of OPC proliferation by rHIgM22 depends on co-stimulatory astrocytic and/or microglial factors. We demonstrate that rHIgM22-mediated activation of PDGFαR is required for stimulation of OPC proliferation. We propose that rHIgM22 lowers the PDGF threshold required for OPC proliferation and protection, which can result in remyelination of CNS lesions.

  19. Fhit Nuclear Import Following EGF Stimulation Sustains Proliferation of Breast Cancer Cells.

    Science.gov (United States)

    Bianchi, Francesca; Sasso, Marianna; Turdo, Federica; Beretta, Giovanni L; Casalini, Patrizia; Ghirelli, Cristina; Sfondrini, Lucia; Ménard, Sylvie; Tagliabue, Elda; Campiglio, Manuela

    2015-11-01

    The tumor-suppressor protein fragile histidine triad (Fhit) exerts its functions in the cytoplasm, although some reports suggest that it may also act in the nucleus. We previously showed that cytosolic Fhit protein levels in cancer cell lines stimulated to proliferate were reduced by proteasomal degradation. Here, we demonstrate that Fhit is physiologically present in the nucleus of breast cancer cell lines and tissues at a low level and that proliferative stimulation increases nuclear levels. Breast cancer cells expressing the FhitY114F mutant, which do not undergo proteasomal degradation, contained mutated Fhit in the nucleus, while cells treated with a proteasome inhibitor accumulated nuclear Fhit during proliferation. Thus, Fhit nuclear shuttling and proteasome degradation phenomena occur independently. When Fhit was coupled to a nuclear localization sequence, the proliferation rate of the transfected cells increased together with levels of proliferation pathway mediators cyclin D1, phospho-MAPK, and phospho-STAT3. Fhit nuclear translocation upon mitogenic stimulation may represent a new regulatory mechanism that allows rapid restoration of Fhit cytoplasmic levels and promotes the proliferation cascade activated by mitogenic stimulation.

  20. Investigation of In Vitro Bone Cell Adhesion and Proliferation on Ti Using Direct Current Stimulation.

    Science.gov (United States)

    Bodhak, Subhadip; Bose, Susmita; Kinsel, William C; Bandyopadhyay, Amit

    2012-12-01

    Our objective was to establish an in vitro cell culture protocol to improve bone cell attachment and proliferation on Ti substrate using direct current stimulation. For this purpose, a custom made electrical stimulator was developed and a varying range of direct currents, from 5 to 25 µA, were used to study the current stimulation effect on bone cells cultured on conducting Ti samples in vitro. Cell-materials interaction was studied for a maximum of 5 days by culturing with human fetal osteoblast cells (hFOB). The direct current was applied in every 8 h time interval and the duration of electrical stimulation was kept constant at 15 min for all cases. In vitro results showed that direct current stimulation significantly favored bone cell attachment and proliferation in comparison to nonstimulated Ti surface. Immunochemistry and confocal microscopy results confirmed that the cell adhesion was most pronounced on 25 µA direct current stimulated Ti surfaces as hFOB cells expressed higher vinculin protein with increasing amount of direct current. Furthermore, MTT assay results established that cells grew 30% higher in number under 25 µA electrical stimulation as compared to nonstimulated Ti surface after 5 days of culture period. In this work we have successfully established a simple and cost effective in vitro protocol offering easy and rapid analysis of bone cell-materials interaction which can be used in promotion of bone cell attachment and growth on Ti substrate using direct current electrical stimulation in an in vitro model.

  1. Differential cell-matrix responses in hypoxia-stimulated aortic versus mitral valves.

    Science.gov (United States)

    Sapp, Matthew C; Krishnamurthy, Varun K; Puperi, Daniel S; Bhatnagar, Saheba; Fatora, Gabrielle; Mutyala, Neelesh; Grande-Allen, K Jane

    2016-12-01

    Tissue oxygenation often plays a significant role in disease and is an essential design consideration for tissue engineering. Here, oxygen diffusion profiles of porcine aortic and mitral valve leaflets were determined using an oxygen diffusion chamber in conjunction with computational models. Results from these studies revealed the differences between aortic and mitral valve leaflet diffusion profiles and suggested that diffusion alone was insufficient for normal oxygen delivery in mitral valves. During fibrotic valve disease, leaflet thickening due to abnormal extracellular matrix is likely to reduce regional oxygen availability. To assess the impact of low oxygen levels on valve behaviour, whole leaflet organ cultures were created to induce leaflet hypoxia. These studies revealed a loss of layer stratification and elevated levels of hypoxia inducible factor 1-alpha in both aortic and mitral valve hypoxic groups. Mitral valves also exhibited altered expression of angiogenic factors in response to low oxygen environments when compared with normoxic groups. Hypoxia affected aortic and mitral valves differently, and mitral valves appeared to show a stenotic, rheumatic phenotype accompanied by significant cell death. These results indicate that hypoxia could be a factor in mid to late valve disease progression, especially with the reduction in chondromodulin-1 expression shown by hypoxic mitral valves. © 2016 The Author(s).

  2. BDNF, produced by a TPO-stimulated megakaryocytic cell line, regulates autocrine proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Shogo [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Research Fellow of the Japan Society for the Promotion of Science, Tokyo (Japan); Nagasawa, Ayumi; Masuda, Yuya; Tsunematsu, Tetsuya [Graduate School of Health Sciences, Hokkaido University, Sapporo (Japan); Hayasaka, Koji; Matsuno, Kazuhiko; Shimizu, Chikara [Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo (Japan); Ozaki, Yukio [Department of Clinical and Laboratory Medicine, Faculty of Medicine, University of Yamanashi (Japan); Moriyama, Takanori, E-mail: moriyama@hs.hokuda.ac.jp [Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo (Japan)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer It has been thought that BDNF is not produced in the megakaryocytic lineage. Black-Right-Pointing-Pointer MEG-01 produces BDNF upon TPO stimulation and regulates its proliferation. Black-Right-Pointing-Pointer BDNF accelerates proliferation of MEG-01 in an autocrine manner. Black-Right-Pointing-Pointer BDNF may be an autocrine MEG-CSF, which regulates megakaryopoiesis. -- Abstract: While human platelets release endogenous brain-derived neurotrophic factor (BDNF) upon activation, a previous report on MEG-01, a megakaryocytic cell line, found no trace of BDNF production, and the pathophysiological function of platelet BDNF has remained elusive. In the present study, we demonstrate that MEG-01 produces BDNF in the presence of TPO and that this serves to potentiate cell proliferation. Our in vitro findings suggest that BDNF regulates MEG-01 proliferation in an autocrine manner, and we suggest that BDNF may be a physiological autocrine regulator of megakaryocyte progenitors.

  3. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  4. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

    Directory of Open Access Journals (Sweden)

    Olga García-Martínez

    Full Text Available In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63 proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis in adulthood and the elderly.

  5. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation

    Science.gov (United States)

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11–16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18–22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9–13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly. PMID:26930190

  6. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

    Science.gov (United States)

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly.

  7. Investigation of in vitro bone cell adhesion and proliferation on Ti using direct current stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Bodhak, Subhadip; Bose, Susmita [W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States); Kinsel, William C. [Mechanical Engineering, Washington State University, Tri-Cities, WA (United States); Bandyopadhyay, Amit, E-mail: amitband@wsu.edu [W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164-2920 (United States)

    2012-12-01

    Our objective was to establish an in vitro cell culture protocol to improve bone cell attachment and proliferation on Ti substrate using direct current stimulation. For this purpose, a custom made electrical stimulator was developed and a varying range of direct currents, from 5 to 25 {mu}A, was used to study the current stimulation effect on bone cells cultured on conducting Ti samples in vitro. Cell-material interaction was studied for a maximum of 5 days by culturing with human fetal osteoblast cells (hFOB). The direct current was applied in every 8 h time interval and the duration of electrical stimulation was kept constant at 15 min for all cases. In vitro results showed that direct current stimulation significantly favored bone cell attachment and proliferation in comparison to nonstimulated Ti surface. Immunochemistry and confocal microscopy results confirmed that the cell adhesion was most pronounced on 25 {mu}A direct current stimulated Ti surfaces as hFOB cells expressed higher vinculin protein with increasing amount of direct current. Furthermore, MTT assay results established that cells grew 30% higher in number under 25 {mu}A electrical stimulation as compared to nonstimulated Ti surface after 5 days of culture period. In this work we have successfully established a simple and cost effective in vitro protocol offering easy and rapid analysis of bone cell-material interaction which can be used in promotion of bone cell attachment and growth on Ti substrate using direct current electrical stimulation in an in vitro model. - Highlights: Black-Right-Pointing-Pointer D.C. stimulation was used to enhance in vitro bone cell adhesion and proliferation. Black-Right-Pointing-Pointer Cells cultured on Ti were stimulated by using a custom made electrical stimulator. Black-Right-Pointing-Pointer Optimization was performed by using a varying range of direct currents {approx} 5 to 25 {mu}A. Black-Right-Pointing-Pointer 25 {mu}A stimulation was found most beneficial

  8. Control of proliferation rate of N27 dopaminergic neurons using Transcranial Magnetic Stimulation orientation

    Science.gov (United States)

    Meng, Yiwen; Hadimani, Ravi; Anantharam, Vellareddy; Kanthasamy, Anumantha; Jiles, David

    2015-03-01

    Transcranial magnetic stimulation (TMS) has been used to investigate possible treatments for a variety of neurological disorders. However, the effect that magnetic fields have on neurons has not been well documented in the literature. We have investigated the effect of different orientation of magnetic field generated by TMS coils with a monophasic stimulator on the proliferation rate of N27 neuronal cells cultured in flasks and multi-well plates. The proliferation rate of neurons would increase by exposed horizontally adherent N27 cells to a magnetic field pointing upward through the neuronal proliferation layer compared with the control group. On the other hand, proliferation rate would decrease in cells exposed to a magnetic field pointing downward through the neuronal growth layer compared with the control group. We confirmed results obtained from the Trypan-blue and automatic cell counting methods with those from the CyQuant and MTS cell viability assays. Our findings could have important implications for the preclinical development of TMS treatments of neurological disorders and represents a new method to control the proliferation rate of neuronal cells.

  9. Mast cell tryptase stimulates myoblast proliferation; a mechanism relying on protease-activated receptor-2 and cyclooxygenase-2

    OpenAIRE

    Côté Claude H; Tremblay Marie-Hélène; Duchesne Elise

    2011-01-01

    Abstract Background Mast cells contribute to tissue repair in fibrous tissues by stimulating proliferation of fibroblasts through the release of tryptase which activates protease-activated receptor-2 (PAR-2). The possibility that a tryptase/PAR-2 signaling pathway exists in skeletal muscle cell has never been investigated. The aim of this study was to evaluate whether tryptase can stimulate myoblast proliferation and determine the downstream cascade. Methods Proliferation of L6 rat skeletal m...

  10. HER4 selectively coregulates estrogen stimulated genes associated with breast tumor cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Han, Wen; Jones, Frank E., E-mail: fjones3@tulane.edu

    2014-01-10

    Highlights: •HER4/4ICD is an obligate coactivator for 37% of estrogen regulated genes. •HER4/4ICD coactivated genes selectively regulate estrogen stimulated proliferation. •Estrogen stimulated tumor cell migration occurs independent of HER4/4ICD. •Disrupting HER4/4ICD and ER coactivated gene expression may suppress breast cancer. -- Abstract: The EGFR-family member HER4 undergoes regulated intramembrane proteolysis (RIP) to generate an intracellular domain (4ICD) that functions as a transcriptional coactivator. Accordingly, 4ICD coactivates the estrogen receptor (ER) and associates with ER at target gene promoters in breast tumor cells. However, the extent of 4ICD coactivation of ER and the functional significance of the 4ICD/ER transcriptional complex is unclear. To identify 4ICD coactivated genes we performed a microarray gene expression analysis of β-estradiol treated cells comparing control MCF-7 breast cancer cells to MCF-7 cells where HER4 expression was stably suppressed using a shRNA. In the MCF-7 cell line, β-estradiol significantly stimulated or repressed by 2-fold or more 726 or 53 genes, respectively. Significantly, HER4/4ICD was an obligate coactivator for 277 or 38% of the β-estradiol stimulated genes. Ingenuity Pathway Analysis of β-estradiol regulated genes identified significant associations with multiple cellular functions regulating cellular growth and proliferation, cell cycle progression, cancer metastasis, decreased hypoplasia, tumor cell migration, apoptotic resistance of tumor cells, and increased transcription. Genes coactivated by 4ICD displayed functional specificity by only significantly contributing to cellular growth and proliferation, cell cycle progression, and decreased hypoplasia. In direct concordance with these in situ results we show that HER4 knockdown in MCF-7 cells results in a loss of estrogen stimulated tumor cell proliferation and cell cycle progression, whereas, estrogen stimulated tumor cell migration was

  11. Hypoxia and hypoxia-inducible factors in leukaemias

    Directory of Open Access Journals (Sweden)

    Margaux eDeynoux

    2016-02-01

    Full Text Available Despite huge improvements in the treatment of leukaemia, the percentage of patients suffering relapse still remains significant. Relapse most often results from a small number of leukaemic stem cells (LSCs within the bone marrow, which are able to self-renew and therefore re-establish the full tumour. The marrow microenvironment contributes considerably in supporting the protection and development of leukaemic cells. LSCs share specific niches with normal haematopoietic stem cells with the niche itself being composed of a variety of cell types including mesenchymal stem/stromal cells, bone cells, immune cells, neuronal cells and vascular cells. A hallmark of the haematopoietic niche is low oxygen partial pressure, indeed this hypoxia is necessary for the long-term maintenance of HSCs. Hypoxia is a strong signal, principally maintained by members of the hypoxia-inducible factor family. In solid tumours, it has been well-established that hypoxia triggers intrinsic metabolic changes and microenvironmental modifications, such as the stimulation of angiogenesis, through activation of HIFs. As leukaemia is not considered a solid tumour, the role of oxygen in the disease was presumed to be inconsequential and remained long overlooked. This view has now been revised since hypoxia has been shown to influence leukaemic cell proliferation, differentiation and resistance to chemotherapy. However, the role of HIF proteins remains controversial with HIFs being considered as either oncogenes or tumour suppressor genes, depending on the study and model. The purpose of this review is to highlight our knowledge of hypoxia and HIFs in leukaemic development and therapeutic resistance, and to discuss the recent hypoxia-based strategies proposed to eradicate leukaemias.

  12. Cyclin C stimulates β-cell proliferation in rat and human pancreatic β-cells

    Science.gov (United States)

    Jiménez-Palomares, Margarita; López-Acosta, José Francisco; Villa-Pérez, Pablo; Moreno-Amador, José Luis; Muñoz-Barrera, Jennifer; Fernández-Luis, Sara; Heras-Pozas, Blanca; Perdomo, Germán; Bernal-Mizrachi, Ernesto

    2015-01-01

    Activation of pancreatic β-cell proliferation has been proposed as an approach to replace reduced functional β-cell mass in diabetes. Quiescent fibroblasts exit from G0 (quiescence) to G1 through pRb phosphorylation mediated by cyclin C/cdk3 complexes. Overexpression of cyclin D1, D2, D3, or cyclin E induces pancreatic β-cell proliferation. We hypothesized that cyclin C overexpression would induce β-cell proliferation through G0 exit, thus being a potential therapeutic target to recover functional β-cell mass. We used isolated rat and human islets transduced with adenovirus expressing cyclin C. We measured multiple markers of proliferation: [3H]thymidine incorporation, BrdU incorporation and staining, and Ki67 staining. Furthermore, we detected β-cell death by TUNEL, β-cell differentiation by RT-PCR, and β-cell function by glucose-stimulated insulin secretion. Interestingly, we have found that cyclin C increases rat and human β-cell proliferation. This augmented proliferation did not induce β-cell death, dedifferentiation, or dysfunction in rat or human islets. Our results indicate that cyclin C is a potential target for inducing β-cell regeneration. PMID:25564474

  13. Omentin-1 Stimulates Human Osteoblast Proliferation through PI3K/Akt Signal Pathway

    Directory of Open Access Journals (Sweden)

    Shan-Shan Wu

    2013-01-01

    Full Text Available It has been presumed that adipokines deriving from adipose tissue may play important roles in bone metabolism. Omentin-1, a novel adipokine, which is selectively expressed in visceral adipose tissue, has been reported to stimulate proliferation and inhibit differentiation of mouse osteoblast. However, little information refers to the effect of omentin-1 on human osteoblast (hOB proliferation. The current study examined the potential effects of omentin-1 on proliferation in hOB and the signal pathway involved. Omentin-1 promoted hOB proliferation in a dose-dependent manner as determined by [3H]thymidine incorporation. Western blot analysis revealed that omentin-1 induced activation of Akt (phosphatidylinositol-3 kinase downstream effector and such effect was impeded by transfection of hOB with Akt-siRNA. Furthermore, LY294002 (a selective PI3K inhibitor and HIMO (a selective Akt inhibitor abolished the omentin-1-induced hOB proliferation. These findings indicate that omentin-1 induces hOB proliferation via the PI3K/Akt signaling pathway and suggest that osteoblast is a direct target of omentin-1.

  14. INTERLEUKIN 10 INHIBITS THE RAT VSMC PROLIFERATION AND COLLAGEN SECRETION STIMULATED BY ANGIOTENSIN Ⅱ

    Institute of Scientific and Technical Information of China (English)

    夏春芳; 霍勇; 尹航; 朱国英; 唐朝枢

    2001-01-01

    Objective. To study the effect of interleukin 10 (IL-10) on the angiotensin Ⅱ(AngⅡ) stimulated rat VSMC proliferation and collagen secretion, and furthermore, explore its mechanism. Methods. On cultured VSMC of rat, 3H-thymine (3H-TdR) and 3H-proline incorporations were used to evaluate the DNA and collagen synthesis, respectively. Western blot and immunoprecipitation were applied to assay the expression and activity of focal adhesion kinase (FAK), respectively. Results. IL-10 (10-8 -10-10g/ml) inhibited the increase of 3H-TdR and 3H-proline incorporation as wellas FAK activity, which was induced by 10-Tmol/L AngⅡ (P 0.05). Conclusion. IL-10 antagonizes the VSMC proliferation and collagen synthesis by regulating FAK activity stimulated by AngⅡ.

  15. Inhibition of DYRK1A Stimulates Human β-Cell Proliferation.

    Science.gov (United States)

    Dirice, Ercument; Walpita, Deepika; Vetere, Amedeo; Meier, Bennett C; Kahraman, Sevim; Hu, Jiang; Dančík, Vlado; Burns, Sean M; Gilbert, Tamara J; Olson, David E; Clemons, Paul A; Kulkarni, Rohit N; Wagner, Bridget K

    2016-06-01

    Restoring functional β-cell mass is an important therapeutic goal for both type 1 and type 2 diabetes (1). While proliferation of existing β-cells is the primary means of β-cell replacement in rodents (2), it is unclear whether a similar principle applies to humans, as human β-cells are remarkably resistant to stimulation of division (3,4). Here, we show that 5-iodotubercidin (5-IT), an annotated adenosine kinase inhibitor previously reported to increase proliferation in rodent and porcine islets (5), strongly and selectively increases human β-cell proliferation in vitro and in vivo. Remarkably, 5-IT also increased glucose-dependent insulin secretion after prolonged treatment. Kinome profiling revealed 5-IT to be a potent and selective inhibitor of the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) and cell division cycle-like kinase families. Induction of β-cell proliferation by either 5-IT or harmine, another natural product DYRK1A inhibitor, was suppressed by coincubation with the calcineurin inhibitor FK506, suggesting involvement of DYRK1A and nuclear factor of activated T cells signaling. Gene expression profiling in whole islets treated with 5-IT revealed induction of proliferation- and cell cycle-related genes, suggesting that true proliferation is induced by 5-IT. Furthermore, 5-IT promotes β-cell proliferation in human islets grafted under the kidney capsule of NOD-scid IL2Rg(null) mice. These results point to inhibition of DYRK1A as a therapeutic strategy to increase human β-cell proliferation.

  16. Mean circulatory filling pressure during splanchnic nerve stimulation and whole-body hypoxia in the anaesthetized cat.

    Science.gov (United States)

    Bower, E A; O'Donnell, C P

    1991-01-01

    1. Mean circulatory filling pressure (MCFP) was measured in cats under chloralose anaesthesia by obstruction of blood flow in the pulmonary artery. Pressures in the aorta, hepatic portal vein and right atrium were recorded, and MCFP was estimated from the value at which all three pressures became equal when blood was pumped from aorta to vena cava during circulatory arrest. Simultaneous equality was not attained at MCFP values below 5 mmHg. 2. In cats ventilated by positive pressure after administration of gallamine, MCFP was 9.7 +/- 0.3 mmHg (n = 14). The values of MCFP measured in six cats before and after administration of gallamine did not differ significantly. Change of blood volume altered MCFP linearly over the range 5-21 mmHg. Noradrenaline (7.5 micrograms kg-1 min-1) increased MCFP from 9.3 +/- 0.9 to 16.5 +/- 0.6 mmHg (n = 4), and phentolamine (2 mg kg-1) reduced it to 5.6 +/- 0.3 mmHg (n = 5). 3. Changes in MCFP were evoked at different circulating blood volumes by stimulation of the splanchnic sympathetic nerves and by whole-body hypoxia. Ablation of all splanchnic nerves reduced MCFP from 9.4 +/- 0.5 to 7.1 +/- 0.3 mmHg (n = 5) and stimulation of their distal ends at 10 Hz increased it by 4.1 +/- 0.4 mmHg (n = 4); similar increments were obtained at different blood volumes and initial values of MCFP. 4. Hypoxia increased MCFP by 0.23 mmHg per 1 mmHg fall in arterial oxygen tension below Pa,O2 56 mmHg (r = -0.86; n = 24). Similar increments were obtained at different blood volumes and initial values of MCFP. Ablation of all splanchnic nerves reduced the increments by 60%, and administration of phentolamine abolished them.

  17. The effect of oscillatory mechanical stimulation on osteoblast attachment and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Aryaei, Ashkan [Department of Mechanical Engineering, College of Engineering, University of Toledo, Toledo, OH 43606 (United States); Jayasuriya, Ambalangodage C., E-mail: a.jayasuriya@utoledo.edu [Department of Orthopaedic Surgery, College of Medicine and Life Sciences, University of Toledo, Toledo, OH 43614 (United States)

    2015-07-01

    The aim of this paper is to investigate the effect of the magnitude and duration of oscillatory mechanical stimulation on osteoblast attachment and proliferation as well as the time gap between seeding and applying the stimulation. Cells were exposed to three levels of speed at two different conditions. For the first group, mechanical shear stress was applied after 20 min of cell seeding. For the second group there was no time gap between cell seeding and applying mechanical stimulation. The total area subjected to shear stress was divided into three parts and for each part a comparative study was conducted at defined time points. Our results showed that both shear stress magnitude and the time gap between cell seeding and applying shear stress, are important in further cell proliferation and attachment. The effect of shear stress was not significant at lower speeds for both groups at earlier time points. However, a higher percentage of area was covered by cells at later time points under shear stress. In addition, the time gap can also improve osteoblast attachment. For the best rate of cell attachment and proliferation, the magnitude of shear stress and time gap should be optimized. The results of this paper can be utilized to improve cell attachment and proliferation in bioreactors. - Highlights: • The effect of oscillatory mechanical stimulation on osteoblast functions was studied. • Cells were exposed at three levels of speed to attach cells. • Shear stress magnitude and time gap are important for cell functions. • Cells start developing extracellular components at the early stage of seeding.

  18. Inosine Released from Dying or Dead Cells Stimulates Cell Proliferation via Adenosine Receptors

    Directory of Open Access Journals (Sweden)

    Yi Zhao

    2017-04-01

    Full Text Available IntroductionMany antitumor therapies induce apoptotic cell death in order to cause tumor regression. Paradoxically, apoptotic cells are also known to promote wound healing, cell proliferation, and tumor cell repopulation in multicellular organisms. We aimed to characterize the nature of the regenerative signals concentrated in the micromilieu of dead and dying cells.MethodsCultures of viable melanoma B16F10 cells, mouse fibroblasts, and primary human fibroblast-like synoviocytes (FLS in the presence of dead and dying cells, their supernatants (SNs, or purified agonists and antagonists were used to evaluate the stimulation of proliferation. Viable cell quantification was performed by either flow cytometry of harvested cells or by crystal violet staining of adherent cells. High-performance liquid chromatography and liquid chromatography coupled with mass spectrometry of cell SNs were deployed to identify the nature of growth-promoting factors. Coimplantation of living cells in the presence of SNs collected from dead and dying cells and specific agonists was used to evaluate tumor growth in vivo.ResultsThe stimulation of proliferation of few surviving cells by bystander dead cells was confirmed for melanoma cells, mouse fibroblasts, and primary FLS. We found that small soluble molecules present in the protein-free fraction of SNs of dead and dying cells were responsible for the promotion of proliferation. The nucleoside inosine released by dead and dying cells acting via adenosine receptors was identified as putative inducer of proliferation of surviving tumor cells after irradiation and heat treatment.ConclusionInosine released by dead and dying cells mediates tumor cell proliferation via purinergic receptors. Therapeutic strategies surmounting this pathway may help to reduce the rate of recurrence after radio- and chemotherapy.

  19. Regulation of hypoxia-inducible factor-1α in human buccal mucosal fibroblasts stimulated with arecoline

    Directory of Open Access Journals (Sweden)

    Yung-Chuan Ho

    2017-06-01

    Full Text Available Hypoxia-inducible factor (HIF-1α is consistently and dramatically upregulated in a variety of fibrotic diseases. The aim of this study was to compare HIF-1α expression from fibroblasts derived from human normal buccal mucosa and oral submucous fibrosis (OSF specimens and further to explore the potential mechanisms that may lead to induce HIF-1α expression. OSF buccal mucosal fibroblasts (BMFs demonstrated significantly higher HIF-1α mRNA expression than normal BMFs (p<0.005. Arecoline, the major areca nut alkaloid, was also found to elevate HIF-1α mRNA expression in a dose-dependent manner (p<0.05. Moreover, arecoline-induced HIF-1α expression was downregulated by mitogen-activated protein kinase inhibitor U0126, phosphatidylinositol 3-kinase inhibitor LY294002, p38 inhibitor SB203580, cyclooxygenase-2 inhibitor NS-398, and glutathione precursor N-acetyl-L-cysteine (p<0.05. Taken together, hypoxia plays an important role in the pathogenesis of areca quid chewing-associated OSF. These pharmacological agents may be further used as chemoprevention agents for OSF.

  20. Stimulation of rat B-lymphocyte proliferation by corticotropin-releasing factor.

    Science.gov (United States)

    McGillis, J P; Park, A; Rubin-Fletter, P; Turck, C; Dallman, M F; Payan, D G

    1989-07-01

    The mitogenic effect of corticotropin-releasing factor (CRF) on rat lymphocytes was investigated. When rat splenocytes were cultured for 48 hr with CFR, a dose-dependent increase in incorporation of 3H-thymidine (3H-Tdr) was observed, with a maximal response at 10 nM CRF. Comparison of the proliferative effect of CRF on enriched populations of B lymphocytes, T lymphocytes, or macrophages revealed that only B lymphocytes responded following treatment with CRF. When lymphocytes derived from different lymphoid tissues were compared, CRF had a greater proliferative effect on lymphocytes derived from gut-associated lymphoid tissue (mesenteric lymph nodes and Peyer's patches) than on lymphocytes from spleen or inguinal lymph nodes; CRF had no effect on thymocytes. Synthetic fragments of CRF were used to determine which portions of the peptide are recognized by lymphocytes. The C-terminal fragments alpha-helical CRF9-41 and CRF21-41 were as potent as native CRF in stimulating B-lymphocyte proliferation, whereas CRF1-20 did not stimulate proliferation. The activity of these peptides suggests that CRF stimulates lymphocyte proliferation by cellular recognition of structural determinants in the C-terminal one-half of the peptide.

  1. Dual-specificity phosphatase 26 (DUSP26) stimulates Aβ42 generation by promoting amyloid precursor protein axonal transport during hypoxia.

    Science.gov (United States)

    Jung, Sunmin; Nah, Jihoon; Han, Jonghee; Choi, Seon-Guk; Kim, Hyunjoo; Park, Jaesang; Pyo, Ha-Kyung; Jung, Yong-Keun

    2016-06-01

    Amyloid beta peptide (Aβ) is a pathological hallmark of Alzheimer's disease (AD) and is generated through the sequential cleavage of amyloid precursor protein (APP) by β- and γ-secretases. Hypoxia is a known risk factor for AD and stimulates Aβ generation by γ-secretase; however, the underlying mechanisms remain unclear. In this study, we showed that dual-specificity phosphatase 26 (DUSP26) regulates Aβ generation through changes in subcellular localization of the γ-secretase complex and its substrate C99 under hypoxic conditions. DUSP26 was identified as a novel γ-secretase regulator from a genome-wide functional screen using a cDNA expression library. The phosphatase activity of DUSP26 was required for the increase in Aβ42 generation through γ-secretase, but this regulation did not affect the amount of the γ-secretase complex. Interestingly, DUSP26 induced the accumulation of C99 in the axons by stimulating anterograde transport of C99-positive vesicles. Additionally, DUSP26 induced c-Jun N-terminal kinase (JNK) activation for APP processing and axonal transport of C99. Under hypoxic conditions, DUSP26 expression levels were elevated together with JNK activation, and treatment with JNK inhibitor SP600125, or the DUSP26 inhibitor NSC-87877, reduced hypoxia-induced Aβ generation by diminishing vesicle trafficking of C99 to the axons. Finally, we observed enhanced DUSP26 expression and JNK activation in the hippocampus of AD patients. Our results suggest that DUSP26 mediates hypoxia-induced Aβ generation through JNK activation, revealing a new regulator of γ-secretase-mediated APP processing under hypoxic conditions. We propose the role of phosphatase dual-specificity phosphatase 26 (DUSP26) in the selective regulation of Aβ42 production in neuronal cells under hypoxic stress. Induction of DUSP26 causes JNK-dependent shift in the subcellular localization of γ-secretase and C99 from the cell body to axons for Aβ42 generation. These findings provide a

  2. Changes in ghrelin, CCK, GLP-1, and peroxisome proliferator-activated receptors in a hypoxia-induced anorexia rat model.

    Science.gov (United States)

    Duraisamy, Arul Joseph; Bayen, Susovan; Saini, Supriya; Sharma, Alpesh Kumar; Vats, Praveen; Singh, Shashi Bala

    2015-01-01

    A high-altitude environment causes appetite loss in unacclimatised humans, leading to weight reduction. Ghrelin, cholecystokinin (CCK), and glucagon like peptide-1 (GLP-1), are gut hormones involved in the regulation of food intake and energy metabolism. The liver is an important site of metabolic regulation, and together with the gut it plays a role in food intake regulation. This study intends to study the time-dependent changes occurring in plasma gut hormones, PPARα, PPARδ, and PGC1α, in the stomach and liver during hypoxia. Male Sprague Dawley rats were exposed to hypobaric hypoxia in a decompression chamber at 7620 m for different durations up to seven days. Hypoxia increased circulating ghrelin from the third day onwards while CCK and GLP-1 decreased immediately. An increase in ghrelin, ghrelin receptor protein levels, and GOAT mRNA levels in the stomach was observed. Stomach cholecystokinin receptor (CCKAR), PPARα, and PPARδ decreased. Liver CCKAR decreased during the first day of hypoxia and returned to normal levels from the third day onwards. PPARα and PGC1α expression increased while PPARδ protein levels reduced in the liver on third day. Hypoxia alters the expression of ghrelin and ghrelin receptor in the stomach, CCKAR in the liver, and PPAR and its cofactors, which might be possible role players in the contribution of gut and liver to anorexia at high altitude.

  3. Macrophage migration inhibitory factor stimulated by Helicobacter pyloriincreases proliferation of gastric epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Harry Hua-Xiang Xia; Shiu Kum Lam; Annie O.O. Chan; Marie Chia Mi Lin; Hsiang Fu Kung; Keiji Ogura; Douglas E. Berg; Benjamin Chun-Yu Wong

    2005-01-01

    AIM: Helicobacter pylori (H pylori) is associated with increased gastric inflammatory and epithelial expression of macrophage migration inhibitory factor (MIF) and gastric epithelial cell proliferation. This study aimed at determining whether H pylori directly stimulates release of MIF in monocytes, whether the cay pathogenicity island (PAI) is involved for this function, and whether MIF stimulated by H pylori increases gastric epithelial cell proliferation in vitro.METHODS: A cytotoxic wild-type H pylori strain (TN2),its three isogenic mutants (TN2△cag, TN2△cagA and TN2△cagE) were co-cultured with cells of a human monocyte cell line, THP-1, for 24 h at different organism/cell ratios. MIF in the supernatants was measured by an ELISA. Cells of a human gastric cancer cell line, MKN45,were then co-cultured with the supernatants, with and without monoclonal anti-MIF antibody for 24 h. The cells were further incubated for 12 h after addition of 3H-thymidine, and the levels of incorporation of 3H-thymidine were measured with a liquid scintillation counter.RESULTS: The wild-type strain and the isogenic mutants,TN2△cagA and TN2△cagE, increased MIF release at organism/cell ratios of 200/1 and 400/1, but not at the ratios of 50/1 and 100/1. However, the mutant TN2△cag did not increase the release of MIF at any of the four ratios.3H-thymidine readings for MKN-45 cells were significantly increased with supernatants derived from the wild-type strain and the mutants TN2△cagA and TN2△cagE, but not from the mutant TN2△cag. Moreover, in the presence of monoclonal anti-MIF antibody, the stimulatory effects of the wild-type strain on cell proliferation disappeared.CONCLUSION: H pylori stimulates MIF release in monocytes, likely through its cag PAI, but not related to cagA or cagE. H pylori-stimulated monocyte culture supernatant increases gastric cell proliferation, which is blocked by anti-MIF antibody, suggesting that MIF plays an important role in H pylori

  4. Fluoride Stimulates the Proliferation of Osteoclasts in vitro by Upregulating MCM3

    Directory of Open Access Journals (Sweden)

    Shengbin Bai

    2016-06-01

    Full Text Available We have previously shown that the expression of the minichromosome maintenance protein 3 (MCM3 gene was upregulated in lymphocytes of patients with skeletal fluorosis. We speculated that increased MCM3 expression may be contribute to osteopathy in patients with skeletal fluorosis. Here, we investigated the effect of fluoride on the proliferation of osteoclasts derived from RAW264.7 cells and the involvement of MCM3. Our MTT assays showed that 0.25 mM NaF markedly stimulated the proliferation of RAW264.7 cells. The RT-PCR and immunoblotting assays revealed that 0.25 mM NaF upregulated MCM3 expression in RAW264.7 cells. The MTT assays additionally demonstrated that stimulation with MCM3 potentiated the effect of fluorine on the proliferation of RAW264.7 cells. These results demonstrated that fluoride at clinical relevant concentration upregulates MCM3 expression in osteoclasts in vitro. We are currently conducting a series of experiments to examine whether increased MCM3 in osteoclasts indeed contributes to osteopathy in skeletal fluorosis.

  5. VEGF-mediated angiogenesis stimulates neural stem cell proliferation and differentiation in the premature brain

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jinqiao, E-mail: jinqiao1977@163.com [Institute of Pediatrics, Children' s Hospital of Fudan University (China); Sha, Bin [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Zhou, Wenhao, E-mail: zhou_wenhao@yahoo.com.cn [Department of Neonatology, Children' s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102 (China); Yang, Yi [Institute of Pediatrics, Children' s Hospital of Fudan University (China)

    2010-03-26

    This study investigated the effects of angiogenesis on the proliferation and differentiation of neural stem cells in the premature brain. We observed the changes in neurogenesis that followed the stimulation and inhibition of angiogenesis by altering vascular endothelial growth factor (VEGF) expression in a 3-day-old rat model. VEGF expression was overexpressed by adenovirus transfection and down-regulated by siRNA interference. Using immunofluorescence assays, Western blot analysis, and real-time PCR methods, we observed angiogenesis and the proliferation and differentiation of neural stem cells. Immunofluorescence assays showed that the number of vWF-positive areas peaked at day 7, and they were highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at every time point. The number of neural stem cells, neurons, astrocytes, and oligodendrocytes in the subventricular zone gradually increased over time in the VEGF up-regulation group. Among the three groups, the number of these cells was highest in the VEGF up-regulation group and lowest in the VEGF down-regulation group at the same time point. Western blot analysis and real-time PCR confirmed these results. These data suggest that angiogenesis may stimulate the proliferation of neural stem cells and differentiation into neurons, astrocytes, and oligodendrocytes in the premature brain.

  6. Thrombin stimulates VSMC proliferation through an EGFR-dependent pathway: involvement of MMP-2.

    Science.gov (United States)

    Smiljanic, Katarina; Obradovic, Milan; Jovanovic, Aleksandra; Djordjevic, Jelena; Dobutovic, Branislava; Jevremovic, Danimir; Marche, Pierre; Isenovic, Esma R

    2014-11-01

    In this study, the role of epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK1/2), heparin-binding EGF-like growth factor (HB-EGF), general metalloproteinases, matrix metalloproteinases-2 (MMP-2) in mediating the mitogenic action of thrombin in rat vascular smooth muscle cells (VSMC) was investigated. The incubation of rat VSMC with thrombin (1 U/ml) for 5 min resulted in significant (p EGFR phosphorylation by 8.5 ± 1.3-fold (p EGFR tyrosine kinase irreversible inhibitor, 10 µM PD169540 (PD), and 20 µM anti-HB-EGF antibody significantly reduced thrombin-stimulated EGFR and ERK1/2 phosphorylation by 81, 72 % and by 48 and 61 %, respectively. Furthermore, the same pretreatments with PD or anti-HB-EGF antibody reduced thrombin-induced VSMC proliferation by 44 and 45 %, respectively. In addition, 30-min pretreatments with 10 µM specific MMP-2 inhibitor significantly reduced thrombin-stimulated phosphorylation of both EGFR and ERK1/2 by 25 %. Moreover, the same pretreatment with MMP-2 inhibitor reduced thrombin-induced VSMC proliferation by 45 %. These results show that the thrombin-induced DNA synthesis correlates with the level of ERK1/2 activation rather than EGFR activation. These results further suggest that thrombin acts through EGFR and ERK 1/2 signaling pathways involving MMP-2 to upregulate proliferation of VSMC.

  7. Electric stimulation at 448 kHz promotes proliferation of human mesenchymal stem cells.

    Science.gov (United States)

    Hernández-Bule, María Luisa; Paíno, Carlos Luis; Trillo, María Ángeles; Úbeda, Alejandro

    2014-01-01

    Capacitive-resistive electric transfer (CRET) is a non invasive electrothermal therapy that applies electric currents within the 400 kHz - 450 kHz frequency range to the treatment of musculoskeletal lesions. Evidence exists that electric currents and electric or magnetic fields can influence proliferative and/or differentiating processes involved in tissue regeneration. This work investigates proliferative responses potentially underlying CRET effects on tissue repair. XTT assay, flow cytometry, immunofluorescence and Western Blot analyses were conducted to asses viability, proliferation and differentiation of adipose-derived stem cells (ADSC) from healthy donors, after short, repeated (5 m On/4 h Off) in vitro stimulation with a 448-kHz electric signal currently used in CRET therapy, applied at a subthermal dose of 50 μA/mm(2) RESULTS: The treatment induced PCNA and ERK1/2 upregulation, together with significant increases in the fractions of ADSC undergoing cycle phases S, G2 and M, and enhanced cell proliferation rate. This proliferative effect did not compromise the multipotential ability of ADSC for subsequent adipogenic, chondrogenic or osteogenic differentiation. These data identify cellular and molecular phenomena potentially underlying the response to CRET and indicate that CRET-induced lesion repair could be mediated by stimulation of the proliferation of stem cells present in the injured tissues. © 2014 S. Karger AG, Basel.

  8. Copper ions stimulate the proliferation of hepatic stellate cells via oxygen stress in vitro.

    Science.gov (United States)

    Xu, San-qing; Zhu, Hui-yun; Lin, Jian-guo; Su, Tang-feng; Liu, Yan; Luo, Xiao-ping

    2013-02-01

    This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of hepatic fibrosis in Wilson's disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Western blotting were used to detect the mRNA and protein expression of platelet-derived growth factor receptor β subunit (PDGFβR), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the proliferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 μmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGFβR was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenomenon could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.

  9. Mast cell tryptase stimulates myoblast proliferation; a mechanism relying on protease-activated receptor-2 and cyclooxygenase-2

    Directory of Open Access Journals (Sweden)

    Côté Claude H

    2011-10-01

    Full Text Available Abstract Background Mast cells contribute to tissue repair in fibrous tissues by stimulating proliferation of fibroblasts through the release of tryptase which activates protease-activated receptor-2 (PAR-2. The possibility that a tryptase/PAR-2 signaling pathway exists in skeletal muscle cell has never been investigated. The aim of this study was to evaluate whether tryptase can stimulate myoblast proliferation and determine the downstream cascade. Methods Proliferation of L6 rat skeletal myoblasts stimulated with PAR-2 agonists (tryptase, trypsin and SLIGKV was assessed. The specificity of the tryptase effect was evaluated with a specific inhibitor, APC-366. Western blot analyses were used to evaluate the expression and functionality of PAR-2 receptor and to assess the expression of COX-2. COX-2 activity was evaluated with a commercial activity assay kit and by measurement of PGF2α production. Proliferation assays were also performed in presence of different prostaglandins (PGs. Results Tryptase increased L6 myoblast proliferation by 35% above control group and this effect was completely inhibited by APC-366. We confirmed the expression of PAR-2 receptor in vivo in skeletal muscle cells and in satellite cells and in vitro in L6 cells, where PAR-2 was found to be functional. Trypsin and SLIGKV increased L6 cells proliferation by 76% and 26% above control, respectively. COX-2 activity was increased following stimulation with PAR-2 agonist but its expression remained unchanged. Inhibition of COX-2 activity by NS-398 abolished the stimulation of cell proliferation induced by tryptase and trypsin. Finally, 15-deoxy-Δ-12,14-prostaglandin J2 (15Δ-PGJ2, a product of COX-2-derived prostaglandin D2, stimulated myoblast proliferation, but not PGE2 and PGF2α. Conclusions Taken together, our data show that tryptase can stimulate myoblast proliferation and this effect is part of a signaling cascade dependent on PAR-2 activation and on the downstream

  10. Angiotensin-(1-7) attenuated long-term hypoxia-stimulated cardiomyocyte apoptosis by inhibiting HIF-1α nuclear translocation via Mas receptor regulation.

    Science.gov (United States)

    Chang, Ruey-Lin; Lin, Jing-Wei; Kuo, Wei-Wen; Hsieh, Dennis Jine-Yuan; Yeh, Yu-Lan; Shen, Chia-Yao; Day, Cecilia-Hsuan; Ho, Tsung-Jung; Viswanadha, Vijaya Padma; Huang, Chih-Yang

    2016-02-01

    Extreme hypoxia often leads to myocardial apoptosis and causes heart failure. Angiotensin-(1-7)Ang-(1-7) is well known for its cardio-protective effects. However, the effects of Ang-(1-7) on long-term hypoxia (LTH)-induced apoptosis remain unknown. In this study, we found that Ang-(1-7) reduced myocardial apoptosis caused by hypoxia through the Mas receptor. Activation of the Ang-(1-7)/Mas axis down-regulated the hypoxia pro-apoptotic signaling cascade by decreasing the protein levels of hypoxia-inducible factor 1α (HIF-1α) and insulin-like growth factor binding protein-3 (IGFBP3). Moreover, the Ang-(1-7)/Mas axis further inhibited HIF-1α nuclear translocation. On the other hand, Ang-(1-7) activated the IGF1R/PI3K/Akt signaling pathways, which mediate cell survival. However, the above effects were abolished by A779 treatment or silencing of Mas expression. Taken together, our findings indicate that the Ang-(1-7)/Mas axis protects cardiomyocytes from LTH-stimulated apoptosis. The protective effect of Ang-(1-7) is associated with the inhibition of HIF-1α nuclear translocation and the induction of IGF1R and Akt phosphorylation.

  11. INTERLEUKIN 10 INHIBITS THE RAT VSMC PROLIFERATION AND COLLAGEN SECRETION STIMULATED BY ANGIOTENSIN Ⅱ

    Institute of Scientific and Technical Information of China (English)

    夏春芳; 霍勇; 尹航; 朱国英; 唐朝枢

    2001-01-01

    Objective. To study the effect of interleukin 10 (IL-10) on the angiotensin II (AagII) stimulated rat VSMC proliferation and collagen secretion, and furthermore, explore its mechanism.Methods. On cultured VSMC of rat, 3H-thymine (3H-TdR) and 3H-proline incorporations were used to evaluate the DNA and collagen synthesis, respectively. Western blot and immunoprecipitation were applied to assay the expression and activity of focal adhesion kinase (FAK), respectively.Results. IL-10 (10-8 ~ 10-10g/ml) inhibited the increase of 3H-TdR and 3H-proline incorporation as well as FAK activity, which was induced by 10-7mol/L AngI ( P < 0. 05 or P < 0. 01 ). IL-10 also obviously downregulated the synthesis and secretion of collagen by AngII stimulated VSMC. But there was no difference in the protein expression of FAK among all the groups ( P > 0. 05).Conclusion. IL-10 antagonizes the VSMC proliferation and collagen synthesis by regulating FAK activity stimulated by AngII.

  12. Low doses of TiO2-polyethylene glycol nanoparticles stimulate proliferation of hepatocyte cells.

    Science.gov (United States)

    Sun, Qingqing; Kanehira, Koki; Taniguchi, Akiyoshi

    2016-01-01

    This paper describes the effect of low concentrations of 100 nm polyethylene glycol-modified TiO2 nanoparticles (TiO2-PEG NPs) on HepG2 hepatocellular carcinoma cells. Proliferation of HepG2 cells increased significantly when the cells were exposed to low doses (TiO2-PEG NPs. These results were further confirmed by cell counting experiments and cell cycle assays. Cellular uptake assays were performed to determine why HepG2 cells proliferate with low-dose exposure to TiO2-PEG NPs. The results showed that exposure to lower doses of NPs led to less cellular uptake, which in turn decreased cytotoxicity. We therefore hypothesized that TiO2-PEG NPs could affect the activity of hepatocyte growth factor receptors (HGFRs), which bind to hepatocyte growth factor and stimulate cell proliferation. The localization of HGFRs on the surface of the cell membrane was detected via immunofluorescence staining and confocal microscopy. The results showed that HGFRs aggregate after exposure to TiO2-PEG NPs. In conclusion, our results indicate that TiO2-PEG NPs have the potential to promote proliferation of HepG2 cells through HGFR aggregation and suggest that NPs not only exhibit cytotoxicity but also affect cellular responses.

  13. Magnesium used in bioabsorbable stents controls smooth muscle cell proliferation and stimulates endothelial cells in vitro.

    Science.gov (United States)

    Sternberg, Katrin; Gratz, Matthias; Koeck, Kathleen; Mostertz, Joerg; Begunk, Robert; Loebler, Marian; Semmling, Beatrice; Seidlitz, Anne; Hildebrandt, Petra; Homuth, Georg; Grabow, Niels; Tuemmler, Conny; Weitschies, Werner; Schmitz, Klaus-Peter; Kroemer, Heyo K

    2012-01-01

    Magnesium-based bioabsorbable cardiovascular stents have been developed to overcome limitations of permanent metallic stents, such as late stent thrombosis. During stent degradation, endothelial and smooth muscle cells will be exposed to locally high magnesium concentrations with yet unknown physiological consequences. Here, we investigated the effects of elevated magnesium concentrations on human coronary artery endothelial and smooth muscle cell (HCAEC, HCASMC) growth and gene expression. In the course of 24 h after incubation with magnesium chloride solutions (1 or 10 mM) intracellular magnesium level in HCASMC raised from 0.55 ± 0.25 mM (1 mM) to 1.38 ± 0.95 mM (10 mM), while no increase was detected in HCAEC. Accordingly, a DNA microarray-based study identified 69 magnesium regulated transcripts in HCAEC, but 2172 magnesium regulated transcripts in HCASMC. Notably, a significant regulation of various growth factors and extracellular matrix components was observed. In contrast, viability and proliferation of HCAEC were increased at concentrations of up to 25 mM magnesium chloride, while in HCASMC viability and proliferation appeared to be unaffected. Taken together, our data indicate that magnesium halts smooth muscle cell proliferation and stimulates endothelial cell proliferation, which might translate into a beneficial effect in the setting of stent associated vascular injury.

  14. LIF is a contraction-induced myokine stimulating human myocyte proliferation

    DEFF Research Database (Denmark)

    Broholm, Christa; Laye, Matthew J; Brandt, Claus

    2011-01-01

    Background: The cytokine leukemia inhibitory factor (LIF) is expressed by skeletal muscle and induces proliferation of myoblasts. We hypothesized that LIF is a contraction-induced myokine functioning in an autocrine fashion to activate gene regulation of human muscle satellite cell proliferation....... Methods: Skeletal muscle LIF expression, regulation and action were examined in two models: 1) Young men performing a bout of heavy resistance exercise of the quadriceps muscle and 2) cultured primary human satellite cells. Results: Resistance exercise induced a 9-fold increase in LIF mRNA content...... in skeletal muscle, but LIF was not detectable in plasma of the subjects. However, electrically stimulated cultured human myotubes produced and secreted LIF, suggesting that LIF is a myokine with local effects. The well-established exercise-induced signaling molecules PI3K, Akt and mTor contributed...

  15. Altered differentiation and paracrine stimulation of mammary epithelial cell proliferation by conditionally activated Smoothened.

    Science.gov (United States)

    Visbal, Adriana P; LaMarca, Heather L; Villanueva, Hugo; Toneff, Michael J; Li, Yi; Rosen, Jeffrey M; Lewis, Michael T

    2011-04-01

    The Hedgehog (Hh) signaling network is critical for patterning and organogenesis in mammals, and has been implicated in a variety of cancers. Smoothened (Smo), the gene encoding the principal signal transducer, is overexpressed frequently in breast cancer, and constitutive activation in MMTV-SmoM2 transgenic mice caused alterations in mammary gland morphology, increased proliferation, and changes in stem/progenitor cell number. Both in transgenic mice and in clinical specimens, proliferative cells did not usually express detectable Smo, suggesting the hypothesis that Smo functioned in a non-cell autonomous manner to stimulate proliferation. Here, we employed a genetically tagged mouse model carrying a Cre-recombinase-dependent conditional allele of constitutively active Smo (SmoM2) to test this hypothesis. MMTV-Cre- or adenoviral-Cre-mediated SmoM2 expression in the luminal epithelium, but not in the myoepithelium, was required for the hyper-proliferative phenotypes. High levels of proliferation were observed in cells adjacent or in close-proximity to Smo expressing cells demonstrating that SmoM2 expressing cells were stimulating proliferation via a paracrine or juxtacrine mechanism. In contrast, Smo expression altered luminal cell differentiation in a cell-autonomous manner. SmoM2 expressing cells, purified by fluorescence activated cell sorting (FACS) via the genetic fluorescent tag, expressed high levels of Ptch2, Gli1, Gli2, Jag2 and Dll-1, and lower levels of Notch4 and Hes6, in comparison to wildtype cells. These studies provide insight into the mechanism of Smo activation in the mammary gland and its possible roles in breast tumorigenesis. In addition, these results also have potential implications for the interpretation of proliferative phenotypes commonly observed in other organs as a consequence of hedgehog signaling activation.

  16. Estrogen Stimulates Proliferation and Differentiation of Neural Stem/Progenitor Cells through Different Signal Transduction Pathways

    Directory of Open Access Journals (Sweden)

    Makiko Okada

    2010-10-01

    Full Text Available Our previous study indicated that both 17β-estradiol (E2, known to be an endogenous estrogen, and bisphenol A (BPA, known to be a xenoestrogen, could positively influence the proliferation or differentiation of neural stem/progenitor cells (NS/PCs. The aim of the present study was to identify the signal transduction pathways for estrogenic activities promoting proliferation and differentiation of NS/PCs via well known nuclear estrogen receptors (ERs or putative membrane-associated ERs. NS/PCs were cultured from the telencephalon of 15-day-old rat embryos. In order to confirm the involvement of nuclear ERs for estrogenic activities, their specific antagonist, ICI-182,780, was used. The presence of putative membrane-associated ER was functionally examined as to whether E2 can activate rapid intracellular signaling mechanism. In order to confirm the involvement of membrane-associated ERs for estrogenic activities, a cell-impermeable E2, bovine serum albumin-conjugated E2 (E2-BSA was used. We showed that E2 could rapidly activate extracellular signal-regulated kinases 1/2 (ERK 1/2, which was not inhibited by ICI-182,780. ICI-182,780 abrogated the stimulatory effect of these estrogens (E2 and BPA on the proliferation of NS/PCs, but not their effect on the differentiation of the NS/PCs into oligodendroglia. Furthermore, E2-BSA mimicked the activity of differentiation from NS/PCs into oligodendroglia, but not the activity of proliferation. Our study suggests that (1 the estrogen induced proliferation of NS/PCs is mediated via nuclear ERs; (2 the oligodendroglial generation from NS/PCs is likely to be stimulated via putative membrane‑associated ERs.

  17. Galvanic vestibular stimulation impairs cell proliferation and neurogenesis in the rat hippocampus but not spatial memory.

    Science.gov (United States)

    Zheng, Yiwen; Geddes, Lisa; Sato, Go; Stiles, Lucy; Darlington, Cynthia L; Smith, Paul F

    2014-05-01

    Galvanic vestibular stimulation (GVS) is a method of activating the peripheral vestibular system using direct current that is widely employed in clinical neurological testing. Since movement is recognized to stimulate hippocampal neurogenesis and movement is impossible without activation of the vestibular system, we speculated that activating the vestibular system in rats while minimizing movement, by delivering GVS under anesthesia, would affect hippocampal cell proliferation and neurogenesis, and spatial memory. Compared with the sham control group, the number of cells incorporating the DNA replication marker, bromodeoxyuridine (BrdU), was significantly reduced in the bilateral hippocampi in both the cathode left-anode right and cathode right-anode left stimulation groups (P ≤ 0.0001). The majority of the BrdU(+ve) cells co-expressed Ki-67, a marker for the S phase of the cell cycle, suggesting that these BrdU(+ve) cells were still in the cell cycle; however, there was no significant difference in the degree of co-labeling between the two stimulation groups. Single labeling for doublecortin (DCX), a marker of immature neurons, showed that while there was no significant difference between the different groups in the number of DCX(+ve) cells in the right dentate gryus, in the left dentate gyrus there was a significant decrease in the cathode left-anode right group compared with the sham controls (P ≤ 0.03). Nonetheless, when animals were tested in place recognition, object exploration and Morris water maze tasks, there were no significant differences between the GVS groups and the sham controls. These results suggest that GVS can have striking effects on cell proliferation and possibly neurogenesis in the hippocampus, without affecting spatial memory.

  18. Phase 1 Trial of Bevacizumab With Concurrent Chemoradiation Therapy for Squamous Cell Carcinoma of the Head and Neck With Exploratory Functional Imaging of Tumor Hypoxia, Proliferation, and Perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Nyflot, Matthew J., E-mail: nyflot@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Kruser, Tim J. [Department of Radiation Oncology, Cadence Cancer Center at Delnor Hospital, Geneva, Illinois (United States); Traynor, Anne M. [Department of Medicine, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Khuntia, Deepak [Varian Medical Systems, Palo Alto, California (United States); Yang, David T. [Departments of Pathology and Laboratory Medicine, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Hartig, Gregory K.; McCulloch, Timothy M. [Department of Surgery-Otolaryngology, H& N Surgery Division, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Wiederholt, Peggy A. [Department of Human Oncology, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Gentry, Lindell R. [Department of Radiology, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Hoang, Tien [Department of Medicine, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Jeraj, Robert [Department of Human Oncology, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Department of Radiology, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); Department of Medical Physics, University of Wisconsin Carbone Cancer Center and School of Medicine and Public Health, Madison, Wisconsin (United States); and others

    2015-04-01

    Purpose: A phase 1 trial was completed to examine the safety and feasibility of combining bevacizumab with radiation and cisplatin in patients with locoregionally advanced squamous cell carcinoma of the head and neck (HNSCC) treated with curative intent. Additionally, we assessed the capacity of bevacizumab to induce an early tumor response as measured by a series of biological imaging studies. Methods and Materials: All patients received a single induction dose of bevacizumab (15 mg/kg) delivered 3 weeks (±3 days) before the initiation of chemoradiation therapy. After the initial dose of bevacizumab, comprehensive head and neck chemoradiation therapy was delivered with curative intent to 70 Gy in 33 fractions with concurrent weekly cisplatin at 30 mg/m{sup 2} and bevacizumab every 3 weeks (weeks 1, 4, 7) with dose escalation from 5 to 10 to 15 mg/kg. All patients underwent experimental imaging with [{sup 18}F]fluorothymidine positron emission tomography (FLT-PET) (proliferation), [{sup 61}Cu]Cu-diacetyl-bis(N4-methylthiosemicarbazone) PET (Cu-ATSM-PET) (hypoxia), and dynamic contrast-enhanced computed tomography (DCE-CT) (perfusion) at 3 time points: before bevacizumab monotherapy, after bevacizumab monotherapy, and during the combined therapy course. Results: Ten patients were enrolled. All had stage IV HNSCC, all achieved a complete response to treatment, and 9 of 10 remain alive, with a mean survival time of 61.3 months. All patients experienced grade 3 toxicity, but no dose-limiting toxicities or significant bleeding episodes were observed. Significant reductions were noted in tumor proliferation (FLT-PET), tumor hypoxia (Cu-ATSM-PET), and DCE-CT contrast enhancement after bevacizumab monotherapy, with further decreases in FLT-PET and Cu-ATSM-PET during the combined therapy course. Conclusions: The incorporation of bevacizumab into comprehensive chemoradiation therapy regimens for patients with HNSCC appears safe and feasible. Experimental imaging

  19. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    Energy Technology Data Exchange (ETDEWEB)

    Gualde, N.; Goodwin, J.S.

    1984-04-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less (/sup 3/H)thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced (/sup 3/H)thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.

  20. 低氧对成体干细胞增殖和分化的影响%Effects of hypoxia on the proliferation and differentiation of adult stem cells

    Institute of Scientific and Technical Information of China (English)

    龚启梅

    2011-01-01

    Hypoxia is one kind of important physiological and pathological phenomenon. Recent studies have shown that hypoxia has effects on the proliferation and differentiation of adult stem cells. Dental pulp is often exposed to ischemia and hypoxia, for the reason that its anatomical location is susceptible to stimuli or injury. Researches on the effects of hypoxia in adult stem cells may provide new methods to study the biological functions of dental pulp stem cells, especially when these cells following exposure to hypoxia. This review emphasized the effects of hypoxia on the proliferation and differentiation of adult stem cells, the mechanism that involved in these processes I the role of hypoxia in the regulation of dental pulp cells proliferation and differentiation.%低氧是一种重要的生理和病理现象,有研究表明低氧可影响成体干细胞的增殖和分化.牙髓组织在受到外伤或刺激时易处于缺血、低氧状态,低氧对成体干细胞影响的研究进展可以为牙髓干细胞的生物学研究提供思路,本文将从低氧对成体干细胞增殖和分化的影响及其相关调控机制、低氧对牙髓细胞增殖和分化的影响等方面作一综述.

  1. Biphasic electrical currents stimulation promotes both proliferation and differentiation of fetal neural stem cells.

    Directory of Open Access Journals (Sweden)

    Keun-A Chang

    Full Text Available The use of non-chemical methods to differentiate stem cells has attracted researchers from multiple disciplines, including the engineering and the biomedical fields. No doubt, growth factor based methods are still the most dominant of achieving some level of proliferation and differentiation control--however, chemical based methods are still limited by the quality, source, and amount of the utilized reagents. Well-defined non-chemical methods to differentiate stem cells allow stem cell scientists to control stem cell biology by precisely administering the pre-defined parameters, whether they are structural cues, substrate stiffness, or in the form of current flow. We have developed a culture system that allows normal stem cell growth and the option of applying continuous and defined levels of electric current to alter the cell biology of growing cells. This biphasic current stimulator chip employing ITO electrodes generates both positive and negative currents in the same culture chamber without affecting surface chemistry. We found that biphasic electrical currents (BECs significantly increased the proliferation of fetal neural stem cells (NSCs. Furthermore, BECs also promoted the differentiation of fetal NSCs into neuronal cells, as assessed using immunocytochemistry. Our results clearly show that BECs promote both the proliferation and neuronal differentiation of fetal NSCs. It may apply to the development of strategies that employ NSCs in the treatment of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases.

  2. Ape1/Ref-1 Stimulates GDNF/GFRalpha1-mediated Downstream Signaling and Neuroblastoma Proliferation.

    Science.gov (United States)

    Kang, Mi-Young; Kim, Kweon Young; Yoon, Young; Kang, Yoonsung; Kim, Hong Beum; Youn, Cha Kyung; Kim, Dong-Hui; Kim, Mi-Hwa

    2009-10-01

    We previously reported that glial cell line-derived neurotropic factor (GDNF) receptor alpha1 (GFRalpha1) is a direct target of apurinic/apyrimidinic endonuclease 1 (Ape1/Ref-1). In the present study, we further analyzed the physiological roles of Ape1/Ref-1-induced GFRalpha1 expression in Neuro2a mouse neuroblastoma cells. Ape1/Ref-1 expression caused the clustering of GFRalpha1 immunoreactivity in lipid rafts in response to GDNF. We also found that Ret, a downstream target of GFRalpha1, was functionally activated by GDNF in Ape1/Ref-1-expressing cells. Moreover, GDNF promoted the proliferation of Ape1/Ref-1-expressing Neuro2a cells. Furthermore, GFRalpha1-specific RNA experiments demonstrated that the downregulation of GFRalpha1 by siRNA in Ape1/Ref-1-expressing cells impaired the ability of GDNF to phosphorylate Akt and PLCgamma-1 and to stimulate cellular proliferation. These results show an association between Ape1/Ref-1 and GDNF/GFRalpha signaling, and suggest a potential molecular mechanism for the involvement of Ape1/Ref-1 in neuronal proliferation.

  3. Mutation of isocitrate dehydrogenase 1 induces glioma cell proliferation via nuclear factor-κB activation in a hypoxia-inducible factor 1-α dependent manner.

    Science.gov (United States)

    Wang, Guoliang; Sai, Ke; Gong, Fanghe; Yang, Qunying; Chen, Furong; Lin, Jian

    2014-05-01

    Recently, mutations of the isocitrate dehydrogenase (IDH) 1 gene, which specifically occur in the majority of low-grade and secondary high-grade gliomas, have drawn particular attention of neuro-oncologists. Mutations of the IDH1 gene have been proposed to have significant roles in the tumorigenesis, progression and prognosis of gliomas. However, the molecular mechanism of the role of IDH1 mutants in gliomagenesis remains to be elucidated. The present study, showed that forced expression of an IDH1 mutant, of which the 132th amino acid residue arginine is substituted by histidine (IDH1R132H), promoted cell proliferation in cultured cells, while wild-type IDH1 overexpression had no effect on cell proliferation. Consistent with previous studies, it was also observed that expression of hypoxia-inducible factor 1-α (HIF1-α) was upregulated in IDH1R132H expressing cells with the induction of vascular endothelial growth factor (VEGF) expression. However, knockdown of VEGF via small RNA interference had no significant influence on the cell proliferation induced by overexpression of IDH1R132H, implying that another signaling pathway may be involved. Next, forced expression of IDH1R132H was found to activate nuclear factor-κB (NF-κB), since the inhibitory IκB protein (IκBα) was highly phosphorylated and the NF-κB p65 subunit was translocated into the nucleus. Notably, knockdown of HIF1-α significantly blocked NF-κB activation, which was induced by the overexpression of IDH1 mutants. In addition, expression of IDH1 mutants markedly induced the NF-κB target gene expression, including cyclin D1 and E and c-myc, which were involved in the regulation of cell proliferation. In conclusion, it was demonstrated that the IDH1 mutant activated NF-κB in a HIF1-α‑dependent manner and was involved in the regulation of cell proliferation.

  4. Hypoxia-inducible factor-2 alpha promotes the proliferation of human placenta-derived mesenchymal stem cells through the MAPK/ERK signaling pathway

    Science.gov (United States)

    Zhu, Chengxing; Yu, Jiong; Pan, Qiaoling; Yang, Jinfeng; Hao, Guangshu; Wang, Yingjie; Li, Lanjuan; Cao, Hongcui

    2016-01-01

    Human placenta-derived mesenchymal stem cells (hPMSCs) reside in a physiologically low-oxygen microenvironment. Hypoxia influences a variety of stem cell cellular activities, frequently involving hypoxia-inducible factor-2 alpha (HIF-2α). This research showed that hPMSCs cultured in hypoxic conditions (5% O2) exhibited a more naïve morphology and had a higher proliferative capability and higher HIF-2α expression than hPMSCs cultured in normoxic conditions (21% O2). Similar to the hypoxic cultures, hPMSCs over-expressing HIF-2α showed higher proliferative potential and higher expression of CCND1 (CyclinD1), MYC (c-Myc), POU5F1 (Oct4) and the components of the MAPK/ERK pathway. In contrast, these genes were down-regulated in the HIF-2α-silenced hPMSCs. After adding the MAPK/ERK inhibitor PD0325901, cell growth and the expression of CCND1 and MYC were inhibited. Furthermore, the chromatin immunoprecipitation (ChIP) assay and electrophoretic mobility shift assay (EMSA) showed that HIF-2α bound to the MAPK3 (ERK1) promoter, indicative of its direct regulation of MAPK/ERK components at the transcriptional level during hPMSC expansion. Taken together, our results suggest that HIF-2α facilitated the preservation of hPMSC stemness and promoted their proliferation by regulating CCND1 and MYC through the MAPK/ERK signaling pathway. PMID:27765951

  5. Hypoxia stimulates prostacyclin synthesis in newborn pulmonary artery endothelium by increasing cyclooxygenase-1 protein.

    Science.gov (United States)

    North, A J; Brannon, T S; Wells, L B; Campbell, W B; Shaul, P W

    1994-07-01

    In newborn lambs, pulmonary prostacyclin (PGI2) production increases acutely in response to low oxygen. We tested the hypothesis that decreased oxygenation directly stimulates PGI2 synthesis in arterial segments and cultured endothelial cells from newborn lamb intrapulmonary arteries. In segments studied at PO2 of 680 mm Hg, the synthesis of PGI2 exceeded prostaglandin E2 (PGE2) by 73%. Endothelium removal lowered PGI2 by 77% and PGE2 by 66%. At low oxygen tension (PO2, 40 mm Hg), PGI2 and PGE2 synthesis rose by 96% and 102%, respectively. Similarly, in endothelial cells studied at PO2 of 680 mm Hg, the synthesis of PGI2 exceeded PGE2 by 50%, and at low oxygen tension both PGI2 and PGE2 increased (89% and 64%, respectively). Endothelial cell PGI2 synthesis maximally stimulated by bradykinin, A23187, or arachidonic acid was also increased at low PO2 by 50%, 66%, and 48%, respectively. PGE2 synthesis was similarly altered, increasing by 33%, 37%, and 41%, respectively. In contrast, lowering oxygen had minimal effect on PGI2 and PGE2 synthesis with exogenous PGH2, which is the product of cyclooxygenase. Immunoblot analyses revealed that there was a 2.6-fold greater abundance of cyclooxygenase-1 protein at PO2 of 40 versus 680 mm Hg, and the increase at lower oxygen tension was inhibited by cycloheximide. The cyclooxygenase-2 isoform was not detected. Thus, attenuated oxygenation directly stimulates PGI2 and PGE2 synthesis in intrapulmonary arterial segments and endothelial cells from newborn lambs. This process is due to enhanced cyclooxygenase activity related to increased abundance of the cyclooxygenase-1 protein, and this effect may be due to increased synthesis of the enzyme protein.

  6. Transspinal direct current stimulation modulates migration and proliferation of adult newly born spinal cells in mice.

    Science.gov (United States)

    Samaddar, Sreyashi; Vazquez, Kizzy; Ponkia, Dipen; Toruno, Pedro; Sahbani, Karim; Begum, Sultana; Abouelela, Ahmed; Mekhael, Wagdy; Ahmed, Zaghloul

    2017-02-01

    Direct current electrical fields have been shown to be a major factor in the regulation of cell proliferation, differentiation, migration, and survival, as well as in the maturation of dividing cells during development. During adulthood, spinal cord cells are continuously produced in both animals and humans, and they hold great potential for neural restoration following spinal cord injury. While the effects of direct current electrical fields on adult-born spinal cells cultured ex vivo have recently been reported, the effects of direct current electrical fields on adult-born spinal cells in vivo have not been characterized. Here, we provide convincing findings that a therapeutic form of transspinal direct current stimulation (tsDCS) affects the migration and proliferation of adult-born spinal cells in mice. Specifically, cathodal tsDCS attracted the adult-born spinal cells, while anodal tsDCS repulsed them. In addition, both tsDCS polarities caused a significant increase in cell number. Regarding the potential mechanisms involved, both cathodal and anodal tsDCS caused significant increases in expression of brain-derived neurotrophic factor, while expression of nerve growth factor increased and decreased, respectively. In the spinal cord, both anodal and cathodal tsDCS increased blood flow. Since blood flow and angiogenesis are associated with the proliferation of neural stem cells, increased blood flow may represent a major factor in the modulation of newly born spinal cells by tsDCS. Consequently, we propose that the method and novel findings presented in the current study have the potential to facilitate cellular, molecular, and/or bioengineering strategies to repair injured spinal cords.NEW & NOTEWORTHY Our results indicate that transspinal direct current stimulation (tsDCS) affects the migratory pattern and proliferation of adult newly born spinal cells, a cell population which has been implicated in learning and memory. In addition, our results suggest a

  7. Hypergravity Stimulates the Extracellular Matrix/Integrin-Signaling Axis and Proliferation in Primary Osteoblasts

    Science.gov (United States)

    Parra, M.; Vercoutere, W.; Roden, C.; Banerjee, I.; Krauser, W.; Holton, E.; Searby, N.; Globus, R.; Almeida, E.

    2003-01-01

    We set out to determine the molecular mechanisms involved in the proliferative response of primary rat osteoblasts to mechanical stimulation using cell culture centrifugation as a model for hypergravity. We hypothesized that this proliferative response is mediated by specific integrin/Extracellular Matrix (ECM) interactions. To investigate this question we developed a cell culture centrifuge and an automated system that performs cell fixation during hypergravity loading. We generated expression vectors for various focal adhesion and cytoskeletal proteins fused to GFP or dsRed and visualized these structures in transfected (or infected) osteoblasts. The actin cytoskeleton was also visualized using rhodamine-phalloidin staining and Focal Adhesion Kinase (FAK) levels were assessed biochemically. We observed that a 24 hour exposure to 50-g stimulated proliferation compared to the 1-g control when cells were plated on fibronectin, collagen Type I , and collagen Type IV, but not on uncoated tissue culture plastic surfaces. This proliferative response was greatest for osteoblasts grown on fibronectin (2-fold increase over 1-g control) and collagen Type I (1.4 fold increase over 1-g control), suggesting that specific matrices and integrins are involved in the signaling pathways required for proliferation. Exposing osteoblasts grown on different matrices to 10-g or 25-g showed that effects on proliferation depended on both matrix type and loading level. We found that osteoblasts exposed to a short pulse of hypergravity during adhesion spread further and had more GFP-FAK containing focal adhesions compared to their 1-g controls. While overall levels of FAK did not change, more FAK was in the active (phosphorylated) form under hypergravity than in the 1-g controls. Cytoskeletal F-actin organization into filaments was also more prominent after brief exposures to hypergravity during the first five minutes of adhesion. These results suggest that specific integrins sense

  8. Combined intermittent hypobaric hypoxia and muscle electro-stimulation: a method to increase circulating progenitor cell concentration?

    Science.gov (United States)

    Corral, Luisa; Javierre, Casimiro; Blasi, Juan; Viscor, Ginés; Ricart, Antoni; Ventura, Josep Lluis

    2014-06-19

    Our goal was to test whether short-term intermittent hypobaric hypoxia (IHH) at a level well tolerated by healthy humans could, in combination with muscle electro-stimulation (ME), mobilize circulating progenitor cells (CPC) and increase their concentration in peripheral circulation. Nine healthy male subjects were subjected, as the active group (HME), to a protocol involving IHH plus ME. IHH exposure consisted of four, three-hour sessions at a barometric pressure of 540 hPa (equivalent to an altitude of 5000 m). These sessions took place on four consecutive days. ME was applied in two separate 20-minute periods during each IHH session. Blood samples were obtained from an antecubital vein on three consecutive days immediately before the experiment, and then 24 h, 48 h, 4 days, 7 days and 14 days after the last day of hypoxic exposure. Four months later a control study was carried out involving seven of the original subjects (CG), who underwent the same protocol of blood samples but without receiving any special stimulus. In comparison with the CG the HME group showed only a non-significant increase in the number of CPC CD34+ cells on the fourth day after the combined IHH and ME treatment. CPC levels oscillated across the study period and provide no firm evidence to support an increased CPC count after IHH plus ME, although it is not possible to know if this slight increase observed is physiologically relevant. Further studies are required to understand CPC dynamics and the physiology and physiopathology of the hypoxic stimulus.

  9. ROS, MAPK/ERK and PKC play distinct roles in EGF-stimulated human corneal cell proliferation and migration.

    Science.gov (United States)

    Huo, Y-N; Chen, W; Zheng, X-X

    2015-11-08

    Cornea is at the outermost surface of eye globe, and it easily receives damage from ultraviolet light exposure, physiology wounding, and infections. It is essential to understand the mechanisms controlling human corneal epithelial (HCE) cell proliferation and wound healing. Epidermal growth factor (EGF) could stimulate cell proliferation and migration in various cell types. Therefore, we investigated the roles and mechanisms of EGF on HCE cell proliferation and migration. CCK-8 kit and wound healing experiment were used to investigate HCE cell proliferation and cell migration, respectively. ROS activity was quantified by DCFDA and flow cytometry. Western blot and Q-PCR were performed to examine protein and RNA levels. EGF could promote HCE cell proliferation and migration in both physiology status and UV irradiation conditions, which is used to mimic the disease condition in human corneal epithelial cells. Interestingly, the promotion effect of EGF on HCE cell proliferation is mainly mediated by activated ROS signaling under disease condition. However, the EGF function is mediated by ROS and MAPK/ERK pathway in EGF-treated corneal epithelial cells in physiology status, in which ROS and MAPK/ERK pathway have no mutual influence on the other signaling pathway in EGF-stimulated corneal epithelial cells. We also revealed that MAPK/ERK pathway instead of ROS mediates EGF-stimulated HCE cell migration. Interestingly, we found that PKC proteins were downregulated by EGF in HCE cells that is partially mediated by ROS signaling, while PKC pathway was not involved in EGF-stimulated corneal cell proliferation and migration. EGF promotes human corneal cell proliferation and migration both in physiology and disease conditions, and ROS, MAPK/ERK and PKC pathways play different roles in these processes.

  10. Bone marrow mesenchymal stromal cells stimulate skeletal myoblast proliferation through the paracrine release of VEGF.

    Directory of Open Access Journals (Sweden)

    Chiara Sassoli

    Full Text Available Mesenchymal stromal cells (MSCs are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies.

  11. Bone Marrow Mesenchymal Stromal Cells Stimulate Skeletal Myoblast Proliferation through the Paracrine Release of VEGF

    Science.gov (United States)

    Chellini, Flaminia; Mazzanti, Benedetta; Nistri, Silvia; Nosi, Daniele; Saccardi, Riccardo; Quercioli, Franco; Zecchi-Orlandini, Sandra; Formigli, Lucia

    2012-01-01

    Mesenchymal stromal cells (MSCs) are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF) by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM) to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies. PMID:22815682

  12. Golli myelin basic proteins stimulate oligodendrocyte progenitor cell proliferation and differentiation in remyelinating adult mouse brain.

    Science.gov (United States)

    Paez, Pablo M; Cheli, Veronica T; Ghiani, Cristina A; Spreuer, Vilma; Handley, Vance W; Campagnoni, Anthony T

    2012-07-01

    Golli myelin basic proteins are necessary for normal myelination, acting via voltage and store-dependent Ca(2+) entry at multiple steps during oligodendrocyte progenitor cell (OPC) development. To date nothing is known regarding the role of golli proteins in demyelination or remyelination events. Here the effects of golli ablation and overexpression in myelin loss and recovery were examined using the cuprizone (CPZ) model of demyelination/remyelination. We found severe demyelination in the corpus callosum (CC) of golli-overexpressing mice (JOE) during the CPZ treatment, which was accompanied by an increased number of reactive astrocytes and activation of microglia/macrophages. During demyelination of JOE brains, a significant increase in the number of proliferating OPCs was found in the CC as well as in the subventricular zone, and our data indicate that these progenitors matured and fully remyelinated the CC of JOE animals after CPZ withdrawal. In contrast, in the absence of golli (golli-KO mice) delayed myelin loss associated with a smaller immune response, and a lower number of OPCs was found in these mice during the CPZ treatment. Furthermore, incomplete remyelination was observed after CPZ removal in large areas of the CC of golli-KO mice, reflecting irregular recovery of the oligodendrocyte population and subsequent myelin sheath formation. Our findings demonstrate that golli proteins sensitize mature oligodendrocytes to CPZ-induced demyelination, while at the same time stimulate the proliferation/recruitment of OPCs during demyelination, resulting in accelerated remyelination.

  13. Diazoxide promotes oligodendrocyte precursor cell proliferation and myelination.

    Directory of Open Access Journals (Sweden)

    Birgit Fogal

    Full Text Available BACKGROUND: Several clinical conditions are associated with white matter injury, including periventricular white matter injury (PWMI, which is a form of brain injury sustained by preterm infants. It has been suggested that white matter injury in this condition is due to altered oligodendrocyte (OL development or death, resulting in OL loss and hypomyelination. At present drugs are not available that stimulate OL proliferation and promote myelination. Evidence suggests that depolarizing stimuli reduces OL proliferation and differentiation, whereas agents that hyperpolarize OLs stimulate OL proliferation and differentiation. Considering that the drug diazoxide activates K(ATP channels to hyperpolarize cells, we tested if this compound could influence OL proliferation and myelination. METHODOLOGY/FINDINGS: Studies were performed using rat oligodendrocyte precursor cell (OPC cultures, cerebellar slice cultures, and an in vivo model of PWMI in which newborn mice were exposed to chronic sublethal hypoxia (10% O(2. We found that K(ATP channel components Kir 6.1 and 6.2 and SUR2 were expressed in oligodendrocytes. Additionally, diazoxide potently stimulated OPC proliferation, as did other K(ATP activators. Diazoxide also stimulated myelination in cerebellar slice cultures. We also found that diazoxide prevented hypomyelination and ventriculomegaly following chronic sublethal hypoxia. CONCLUSIONS: These results identify KATP channel components in OLs and show that diazoxide can stimulate OL proliferation in vitro. Importantly we find that diazoxide can promote myelination in vivo and prevent hypoxia-induced PWMI.

  14. Enhancement of the HIF-1α/15-LO/15-HETE axis promotes hypoxia-induced endothelial proliferation in preeclamptic pregnancy.

    Directory of Open Access Journals (Sweden)

    Dandan Yuan

    Full Text Available Preeclampsia (PE is an extremely serious condition in pregnant women and the leading cause of maternal and fetal morbidity and mortality. Despite active research, the etiological factors of this disorder remain elusive. The increased release of 15-hydroxyeicosatetraenoic acid (15-HETE in the placenta of preeclamptic patients has been studied, but its exact role in PE pathogenesis remains unknown. Mounting evidence shows that PE is associated with placental hypoxia, impaired placental angiogenesis, and endothelial dysfunction. In this study, we confirmed the upregulated expression of hypoxia-inducible factor 1α (HIF-1α and 15-lipoxygenase-1/2 (15-LO-1/2 in patients with PE. Production of the arachidonic acid metabolite, 15-HETE, also increased in the preeclamptic placenta, which suggests enhanced activation of the HIF-1α-15-LO-15-HETE axis. Furthermore, this study is the first to show that the umbilical cord of preeclamptic women contains significantly higher serum concentrations of 15-HETE than that of healthy pregnant women. The results also show that expression of 15-LO-1/2 is upregulated in both human umbilical vein endothelial cells (HUVECs collected from preeclamptic women and in those cultured under hypoxic conditions. Exogenous 15-HETE promotes the migration of HUVECs and in vitro tube formation and promotes cell cycle progression from the G0/G1 phase to the G2/M + S phase, whereas the 15-LO inhibitor, NDGA, suppresses these effects. The HIF-1α/15-LO/15-HETE pathway is therefore significantly associated within the pathology of PE.

  15. The soluble guanylate cyclase stimulator riociguat ameliorates pulmonary hypertension induced by hypoxia and SU5416 in rats.

    Directory of Open Access Journals (Sweden)

    Michaela Lang

    Full Text Available BACKGROUND: The nitric oxide (NO-soluble guanylate cyclase (sGC-cyclic guanosine monophosphate (cGMP signal-transduction pathway is impaired in many cardiovascular diseases, including pulmonary arterial hypertension (PAH. Riociguat (BAY 63-2521 is a stimulator of sGC that works both in synergy with and independently of NO to increase levels of cGMP. The aims of this study were to investigate the role of NO-sGC-cGMP signaling in a model of severe PAH and to evaluate the effects of sGC stimulation by riociguat and PDE5 inhibition by sildenafil on pulmonary hemodynamics and vascular remodeling in severe experimental PAH. METHODS AND RESULTS: Severe angioproliferative PAH was induced in rats by combined exposure to the vascular endothelial growth factor receptor antagonist SU5416 and hypoxia (SUHx. Twenty-one days thereafter rats were randomized to receive either riociguat (10 mg/kg/day, sildenafil (50 mg/kg/day or vehicle by oral gavage, for 14 days until the day of the terminal hemodynamic measurements. Administration of riociguat or sildenafil significantly decreased right ventricular systolic pressure (RVSP. Riociguat significantly decreased RV hypertrophy (RVH (0.55 ± 0.02, p<0.05, increased cardiac output (60.8 ± .8 mL/minute, p<0.05 and decreased total pulmonary resistance (4.03 ± 0.3 mmHg min(-1 ml(-1 100 g BW, p<0.05, compared with sildenafil and vehicle. Both compounds significantly decreased the RV collagen content and improved RV function, but the effects of riociguat on tricuspid annular plane systolic excursion and RV myocardial performance were significantly better than those of sildenafil (p<0.05. The proportion of occluded arteries was significantly lower in animals receiving riociguat than in those receiving vehicle (p<0.05; furthermore, the neointima/media ratio was significantly lower in those receiving riociguat than in those receiving sildenafil or vehicle (p<0.05. CONCLUSION: Riociguat and sildenafil significantly reduced

  16. Effect of hypoxia on the proliferation of porcine bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stem cells in 2- and 3-dimensional culture.

    Science.gov (United States)

    Burian, Egon; Probst, Florian; Palla, Benjamin; Riedel, Christina; Saller, Maximilian Michael; Cornelsen, Matthias; König, Florian; Schieker, Matthias; Otto, Sven

    2017-03-01

    Bone marrow-derived mesenchymal stem cells (MSCs) and adipose-derived mesenchymal stem cells (ASCs) currently represent a promising tool for the regeneration of large bony defects. Therefore, it is pivotal to find the best cell source within the body and the best conditions for in vitro cellular expansion. This study compared cellular response of MSCs and ASCs from a porcine animal in normoxic (21% O2) and hypoxic (2% O2) cell culture conditions via 2D and 3D experimental settings. The effect of constant exposure to hypoxia on primary pig stem cells was evaluated by two methods. First, a cumulative population doublings (cumPD) over a period of 40 days, a metabolic activity assay in both 2D and 3D beta-TCP-PHB scaffolds, followed by analysis of osteogenic differentiation potential in cell monolayers. Our results displayed enhanced cell culture proliferation in 2% O2 for both MSCs and ASCs, with impaired osteogenic differentiation of MSCs. The impact of constant hypoxia on porcine MSCs and ASCs exhibited a statistically significant decrease in osteogenic differentiation under hypoxic conditions with the MSCs. Our data suggest that MSCs and ASCs expanded in hypoxic culture conditions, might be more suitable for use in the clinical setting where large cell numbers are required. When differentiated in normoxic conditions, MSCs showed the highest osteogenic differentiation potential and might be the best choice of cells with consideration to bone repair. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  17. Functional electrical stimulation-facilitated proliferation and regeneration of neural precursor cells in the brains of rats with cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Yun Xiang; Huihua Liu; Tiebin Yan; Zhiqiang Zhuang; Dongmei Jin; Yuan Peng

    2014-01-01

    Previous studies have shown that proliferation of endogenous neural precursor cells cannot alone compensate for the damage to neurons and axons. From the perspective of neural plastici-ty, we observed the effects of functional electrical stimulation treatment on endogenous neural precursor cell proliferation and expression of basic fibroblast growth factor and epidermal growth factor in the rat brain on the infarct side. Functional electrical stimulation was performed in rat models of acute middle cerebral artery occlusion. Simultaneously, we set up a placebo stimulation group and a sham-operated group. Immunohistochemical staining showed that, at 7 and 14 days, compared with the placebo group, the numbers of nestin (a neural precursor cell marker)-positive cells in the subgranular zone and subventricular zone were increased in the functional electrical stimulation treatment group. Western blot assays and reverse-transcription PCR showed that total protein levels and gene expression of epidermal growth factor and basic ifbroblast growth factor were also upregulated on the infarct side. Prehensile traction test results showed that, at 14 days, prehension function of rats in the functional electrical stimulation group was signiifcantly better than in the placebo group. These results suggest that functional electrical stimulation can promote endogenous neural precursor cell proliferation in the brains of acute cerebral infarction rats, enhance expression of basic fibroblast growth factor and epidermal growth factor, and improve the motor function of rats.

  18. 缺氧对成牙骨质细胞增殖、凋亡及缺氧相关基因的影响%Effect of hypoxia on proliferation, apoptosis and hypoxia-related gene of cementoblast-like cells

    Institute of Scientific and Technical Information of China (English)

    吴浩; 韩红娟; 任小华; 梁琳

    2015-01-01

    Objective To investigate the influence of hypoxia on proliferation,apoptosis and hypoxia-related gene of cemento-blast-like cells in order to understand the role of hypoxia in orthodontic-induced cementum absorption.Methods A cell hypoxic model was constructed by using a special incubator.At the same time,cell cultured under normal oxygenic pressure was used as control.MTT, FCM and RT-PCR were used to measure the proliferation ratio,apoptosis ratio and mRNA expressions of HIF-1αand VEGF.Results Hypoxia could depress the cell proliferation,increase apoptosis ratio and induce mRNA expressions of HIF-1αand VEGF of OCCM-30 cells.The expressions of HIF-1αmRNA reached the highest platform at 24 h after hypoxia while the expression of VEGF mRNA started to increase after 36 h of hypoxia.Conclusion Hypoxia could inhibit the cell proliferation and increase the cell apoptosis and hypoxia-relative gene expressions.%目的:探讨不同时间缺氧微环境对成牙骨质样细胞OCCM-30增殖、凋亡及缺氧相关基因的影响,了解缺氧在正畸导致的牙骨质吸收中所起的作用。方法利用三气培养箱构建细胞缺氧模型,以常氧条件培养为对照组,利用MTT法测定细胞增殖率,流式细胞术检测细胞凋亡率,RT-PCR检测HIF-1α、VEGF mRNA等相关基因的表达变化。结果缺氧可以抑制OCCM-30细胞的增殖,明显提高细胞的凋亡率,并能显著诱导HIF-1α和VEGF mRNA基因的表达,HIF-1αmRNA的表达水平在24 h达到顶峰后进入平台期;而VEGF mRNA的表达水平在36 h后开始逐步上调。结论缺氧微环境能抑制OCCM-30细胞增殖,促进调亡及缺氧相关基因的表达。

  19. Graviola inhibits hypoxia-induced NADPH oxidase activity in prostate cancer cells reducing their proliferation and clonogenicity.

    Science.gov (United States)

    Deep, Gagan; Kumar, Rahul; Jain, Anil K; Dhar, Deepanshi; Panigrahi, Gati K; Hussain, Anowar; Agarwal, Chapla; El-Elimat, Tamam; Sica, Vincent P; Oberlies, Nicholas H; Agarwal, Rajesh

    2016-03-16

    Prostate cancer (PCa) is the leading malignancy among men. Importantly, this disease is mostly diagnosed at early stages offering a unique chemoprevention opportunity. Therefore, there is an urgent need to identify and target signaling molecules with higher expression/activity in prostate tumors and play critical role in PCa growth and progression. Here we report that NADPH oxidase (NOX) expression is directly associated with PCa progression in TRAMP mice, suggesting NOX as a potential chemoprevention target in controlling PCa. Accordingly, we assessed whether NOX activity in PCa cells could be inhibited by Graviola pulp extract (GPE) that contains unique acetogenins with strong anti-cancer effects. GPE (1-5 μg/ml) treatment strongly inhibited the hypoxia-induced NOX activity in PCa cells (LNCaP, 22Rv1 and PC3) associated with a decrease in the expression of NOX catalytic and regulatory sub-units (NOX1, NOX2 and p47(phox)). Furthermore, GPE-mediated NOX inhibition was associated with a strong decrease in nuclear HIF-1α levels as well as reduction in the proliferative and clonogenic potential of PCa cells. More importantly, GPE treatment neither inhibited NOX activity nor showed any cytotoxicity against non-neoplastic prostate epithelial PWR-1E cells. Overall, these results suggest that GPE could be useful in the prevention of PCa progression via inhibiting NOX activity.

  20. Hypoxia stimulates invasion and migration of human cervical cancer cell lines HeLa/SiHa through the Rab11 trafficking of integrin αvβ3/FAK/PI3K pathway-mediated Rac1 activation

    Indian Academy of Sciences (India)

    HAO XU; YUAN YUAN; WENQIAN WU; MIN ZHOU; QIAN JIANG; LINJUN NIU; JIAYIN JI; NIANLI LIU; LONGZHEN ZHANG; XIA WANG

    2017-09-01

    Hypoxia plays a key role in tumour cell survival, invasion, and metastasis. An increasing number of studies have attemptedto characterize the tumour response to hypoxia and to identify predictive markers of disease. Here we show that hypoxiaincreases tumour cell invasion and migration by the modulation of Rab11, an important molecule for vesicular trafficking.In our study, we found that Rab11, together with the activation of Rac1, could stimulate invasion and migration of cervicalcancer cell lines HeLa/SiHa in hypoxia. Activation of Rac1 activity by hypoxia seems to be central to carcinoma invasion.We also found that these effects could be related to the integrin αvβ3. In addition, we studied the molecular pathway for thisprocess. Our results showed that in cervical cancer cell lines HeLa/SiHa, Rac1 activation in hypoxia could stimulateinvasion and migration, and this process was mediated by integrin αvβ3-mediated FAK and PI3K phosphorylation.Furthermore, hypoxia induced a dramatic increase in αvβ3 integrin surface expression, and this increase is dependent onRab11. In conclusion, our study might provide a new mechanism for the effect of hypoxia on stimulating cervicalcarcinoma invasion.

  1. Intermittent hypoxia stimulates formation of binuclear neurons in brain cortex- a role of cell fusion in neuroprotection?

    Science.gov (United States)

    Paltsyn, Alexander A; Manukhina, Eugenia B; Goryacheva, Anna V; Downey, H Fred; Dubrovin, Ivan P; Komissarova, Svetlana V; Kubatiev, Aslan A

    2014-05-01

    Oligodendrocyte fusion with neurons in the brain cortex is a part of normal ontogenesis and is a possible means of neuroregeneration. Following such fusion, the oligodendrocyte nucleus undergoes neuron-specific reprogramming, resulting in the formation of binuclear neurons, which doubles the functional capability of the neuron. In this study, we tested the hypothesis that the formation of binuclear neurons is involved in long-term adaptation of the brain to intermittent hypobaric hypoxia, which is known to be neuroprotective. Rats were adapted to hypoxia in an altitude chamber at a simulated altitude of 4000 m above sea level for 14 days (30 min increasing to 4 h, daily). One micrometer sections of the left motor cortex were analyzed by light microscopy. Phases of the fusion and reprogramming process were recorded, and the number of binuclear neurons was counted for all section areas containing pyramidal neurons of layers III-V. For the control group subjected to sham hypoxia, the density of binuclear neurons was 4.49 ± 0.32 mm(2). In the hypoxia-adapted group, this density increased to 5.71 ± 0.39 mm(2) (P neurons did not differ from the number observed in the control group. We suggest that the increased content of binuclear neurons may serve as a structural basis for the neuroprotective effects of the adaptation to hypoxia.

  2. Maturation, proliferation and apoptosis of seminal tubule cells at puberty after administration of estradiol, follicle stimulating hormone or both

    Institute of Scientific and Technical Information of China (English)

    Renata Walczak-Jedrzejowska; Jolanta Slowikowska-Hilczer; Katarzyna Marchlewska; Krzysztof Kula

    2008-01-01

    Aim: To assess proliferative and apoptotic potential of the seminiferous epithelium cells in relation to Sertoli cell maturation in newborn rats under the influence of estradiol, follicle stimulating hormone (FSH) or both agents given together. Methods: From postnatal day (PND) 5 to 15 male rats were daily injected with 12.5 μg of 17β-estradiol benzoate (EB) or 7.5 IU of human purified FSH (hFSH) or EB + hFSH or solvents (control). On postnatal day 16, autopsy was performed. Sertoli cell maturation/function was assessed by morphometry. Proliferation of the semini- ferous epithelium cells was quantitatively evaluated using immunohistochemical labeling against proliferating cell nuclear antigen and apoptosis using the TUNEL method. Results: Although EB inhibited Sertoli cell maturation and hFSH was not effective, a pronounced acceleration of Sertoli cell maturation occurred after EB + hFSH. Whereas hFSH stimulated Sertoli cell proliferation, EB or EB + hFSH inhibited Sertoli cell proliferation. All treatments signifi- cantly stimulated germ cell proliferation. Apoptosis of Sertoli cells increased 9-fold and germ cells 2-fold after EB, and was not affected by hFSH but was inhibited after EB + hFSH. Conclusion: At puberty, estradiol inhibits Sertoli cell maturation, increases Sertoli and germ cell apoptosis but stimulates germ cell proliferation. Estradiol in synergism with FSH, but neither of the hormones alone, accelerates Sertoli cell maturation associated with an increase in germ cell survival. Estradiol and FSH cooperate to induce seminal tubule maturation and trigger first spermatogenesis. (Asian J Androl 2008 Jul; 10: 585-592)

  3. miR-140-5p regulates hypoxia-mediated human pulmonary artery smooth muscle cell proliferation, apoptosis and differentiation by targeting Dnmt1 and promoting SOD2 expression

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanwei; Xu, Jing, E-mail: xujingdoc@163.com

    2016-04-22

    miR-140-5p is down-regulated in patients with pulmonary arterial hypertension (PAH) and experimental models of PAH, and inhibits hypoxia-mediated pulmonary artery smooth muscle cell (PASMC) proliferation in vitro. Delivery of synthetic miR-140-5p prevents and treats established, experimental PAH. DNA methyltransferase 1 (Dnmt1) is up-regulated in PAH associated human PASMCs (HPASMCs), which promotes the development of PAH by hypermethylation of CpG islands within the promoter for superoxide dismutase 2 (SOD2) and down-regulating SOD2 expression. We searched for miR-140-5p targets using TargetScan, PicTar and MiRanda tools, and found that Dnmt1 is a potential target of miR-140-5p. Based on these findings, we speculated that miR-140-5p might target Dnmt1 and regulate SOD2 expression to regulate hypoxia-mediated HPASMC proliferation, apoptosis and differentiation. We detected the expression of miR-140-5p, Dnmt1 and SOD2 by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays, respectively, and found down-regulation of miR-140-5p and SOD2 and up-regulation of Dnmt1 exist in PAH tissues and hypoxia-mediated HPASMCs. Cell proliferation, apoptosis and differentiation detection showed that miR-140-5p inhibits proliferation and promotes apoptosis and differentiation of HPASMCs in hypoxia, while the effect of Dnmt1 on hypoxia-mediated HPASMCs is reversed. Luciferase assay confirmed that miR-140-5p targets Dnmt1 directly. An inverse correlation is also found between miR-140-5p and Dnmt1 in HPASMCs. In addition, we further investigated whether miR-140-5p and Dnmt1 regulate HPASMC proliferation, apoptosis and differentiation by regulating SOD2 expression, and the results confirmed our speculation. Taken together, these results indicated that miR-140-5p at least partly targets Dnmt1 and regulates SOD2 expression to inhibit proliferation and promote apoptosis and differentiation of HPASMCs in hypoxia. - Highlights: • miR-140-5p and SOD2 are down

  4. Preconditioning Human Mesenchymal Stem Cells with a Low Concentration of BMP2 Stimulates Proliferation and Osteogenic Differentiation In Vitro.

    Science.gov (United States)

    Lysdahl, Helle; Baatrup, Anette; Foldager, Casper Bindzus; Bünger, Cody

    2014-12-01

    Clinical trials using bone morphogenetic protein-2 (BMP2) for bone reconstruction have shown promising results. However, the relatively high concentration needed to be effective raises concerns for efficacy and safety. The aim of this study was to investigate the osteogenic effect of an alternative treatment strategy in which human bone marrow-derived mesenchymal stem cells (hMSCs) are preconditioned with low concentrations of BMP2 for a short time in vitro. hMSCs in suspension were stimulated for 15 min with 10 and 20 ng/mL of BMP2. After the BMP2 was removed, the cells were seeded and cultured in osteogenic medium. The effects of preconditioning were analyzed with regard to proliferation and expression of osteogenic markers at both gene and protein level. The results were compared to those from cultures with continuous BMP2 stimulation. A significant increase in proliferation was seen with both precondition and continuous stimulation with BMP2, with no difference between the treatments. Preconditioning with BMP2 significantly increased gene expression of RUNX2, COLI, ALP, and OC, and protein levels of COLI and ALP. This was not found with continuous stimulation. The role of preconditioning with BMP2 in osteogenesis was validated by findings of increased gene expression of SMAD1 and an increase in dual phosphorylation of ser 463 and ser 465 in the SMAD 1/5/8 pathway. We concluded that preconditioning hMSCs with BMP2 stimulates osteogenesis: proliferation with matrix secretion and matrix maturation of hMSCs. This implies that preconditioning with BMP2 might be more effective at inducing proliferation and osteogenic differentiation of hMSCs than continuous stimulation. Preconditioning with BMP2 could benefit the clinical application of BMP2 since side effects from high-dose treatments could be avoided.

  5. Dihydrotestosterone stimulates proliferation and differentiation of fetal calvarial osteoblasts and dural cells and induces cranial suture fusion.

    Science.gov (United States)

    Lin, Ines C; Slemp, Alison E; Hwang, Catherine; Sena-Esteves, Miguel; Nah, Hyun-Duck; Kirschner, Richard E

    2007-10-01

    The higher prevalence of metopic and sagittal suture synostosis in male infants suggests a role for androgens in early craniofacial development. These experiments characterize the influence of androgen stimulation on growth and differentiation of fetal dural and calvarial bone cells and on cranial suture fusion. Primary murine fetal (E18) dural cells and calvarial osteoblasts were isolated and cultured. Cells were treated for 48 hours with 5alpha-dihydrotestosterone (0 to 1000 nM). Cell proliferation was examined by nonradioactive proliferation assay; mRNA expression of alkaline phosphatase, transforming growth factor (TGF)-beta1, and the bone matrix proteins osteopontin, osteocalcin, and type 1 collagen was determined by reverse-transcriptase polymerase chain reaction. In separate experiments, intact fetal calvariae were grown in tissue culture with 10 nM 5alpha-dihydrotestosterone for 7 and 14 days and then examined histologically. Androgen stimulation at 5 nM increased proliferation of fetal dural cells by 46.0 percent and of fetal calvarial osteoblasts by 20.5 percent. Dural expression of osteopontin, osteocalcin, and type 1 collagen was enhanced by 5alpha-dihydrotestosterone, as was that of TGF-beta1 and alkaline phosphatase. Androgen stimulation increased calvarial osteoblast expression of alkaline phosphatase and TGF-beta1 but induced little change in expression of osteocalcin, osteopontin, and type 1 collagen. In tissue culture, 5alpha-dihydrotestosterone stimulated osteoid formation and fusion of sagittal sutures. Androgen stimulation of dural cells and osteoblasts isolated from fetal calvaria promotes cell proliferation and osteoblastic differentiation and can induce cranial suture fusion. These results suggest that sex steroid hormone signaling may stimulate sutural osteogenesis by means of osteodifferentiation of dural cells, thus explaining the male prevalence of nonsyndromic craniosynostosis.

  6. Activation of peroxisome proliferator-activated receptor alpha in rat spinal cord after peripheral noxious stimulation.

    Science.gov (United States)

    Benani, A; Heurtaux, T; Netter, P; Minn, A

    2004-10-07

    Following recurrent noxious stimulation, both functional modification and structural reorganization such as activation of the arachidonate cascade or axon sprouting occur in the central nervous system (CNS). It has been recently proposed that these alterations observed during chronic pain state were supported by an intensification of the lipid metabolism. In this regard, it has been shown that mRNA coding for several fatty acid metabolizing enzymes are up-regulated in the rat lumbar spinal cord in response to persistent nociception induced by a peripheral inflammation. As peroxisome proliferators-activated receptor (PPAR) could mediate such effects, we therefore investigated the activation of this transcription factor in the rat spinal cord following subcutaneous injection of complete Freund's adjuvant (CFA) into a hind paw. In this study, we compared the DNA-binding activity of nuclear proteins extracted from healthy and inflamed rats toward a PPAR response element. Using electrophoretic mobility-shift assay (EMSA), we found that only the PPARalpha isoform was activated in the rat spinal cord after CFA injection. This activation occurred rapidly, as early as 30 min post-CFA injection, and was persistent up to 10 h, reaching a maximum at 6h after CFA injection. In view of the consequences of PPARalpha activation in other tissues, these results suggest that fatty acid utilization is enhanced in the CNS during chronic pain state. Although the physiopathological relevance of PPARalpha activation during hyperalgesia needs further investigation, we provided here a new player in the molecular modeling of pain pathways.

  7. The Oligo Fucoidan Inhibits Platelet-Derived Growth Factor-Stimulated Proliferation of Airway Smooth Muscle Cells.

    Science.gov (United States)

    Yang, Chao-Huei; Tsao, Chiung-Fang; Ko, Wang-Sheng; Chiou, Ya-Ling

    2016-01-09

    In the pathogenesis of asthma, the proliferation of airway smooth muscle cells (ASMCs) is a key factor in airway remodeling and causes airway narrowing. In addition, ASMCs are also the effector cells of airway inflammation. Fucoidan extracted from marine brown algae polysaccharides has antiviral, antioxidant, antimicrobial, anticlotting, and anticancer properties; however, its effectiveness for asthma has not been elucidated thus far. Platelet-derived growth factor (PDGF)-treated primary ASMCs were cultured with or without oligo-fucoidan (100, 500, or 1000 µg/mL) to evaluate its effects on cell proliferation, cell cycle, apoptosis, and Akt, ERK1/2 signaling pathway. We found that PDGF (40 ng/mL) increased the proliferation of ASMCs by 2.5-fold after 48 h (p fucoidan reduced the proliferation of PDGF-stimulated ASMCs by 75%-99% after 48 h (p fucoidan supplementation reduced PDGF-stimulated extracellular signal-regulated kinase (ERK1/2), Akt, and nuclear factor (NF)-κB phosphorylation. Taken together, oligo-fucoidan supplementation might reduce proliferation of PDGF-treated ASMCs through the suppression of ERK1/2 and Akt phosphorylation and NF-κB activation. The results provide basis for future animal experiments and human trials.

  8. The Oligo Fucoidan Inhibits Platelet-Derived Growth Factor-Stimulated Proliferation of Airway Smooth Muscle Cells

    Directory of Open Access Journals (Sweden)

    Chao-Huei Yang

    2016-01-01

    Full Text Available In the pathogenesis of asthma, the proliferation of airway smooth muscle cells (ASMCs is a key factor in airway remodeling and causes airway narrowing. In addition, ASMCs are also the effector cells of airway inflammation. Fucoidan extracted from marine brown algae polysaccharides has antiviral, antioxidant, antimicrobial, anticlotting, and anticancer properties; however, its effectiveness for asthma has not been elucidated thus far. Platelet-derived growth factor (PDGF-treated primary ASMCs were cultured with or without oligo-fucoidan (100, 500, or 1000 µg/mL to evaluate its effects on cell proliferation, cell cycle, apoptosis, and Akt, ERK1/2 signaling pathway. We found that PDGF (40 ng/mL increased the proliferation of ASMCs by 2.5-fold after 48 h (p < 0.05. Oligo-fucoidan reduced the proliferation of PDGF-stimulated ASMCs by 75%–99% after 48 h (p < 0.05 and induced G1/G0 cell cycle arrest, but did not induce apoptosis. Further, oligo-fucoidan supplementation reduced PDGF-stimulated extracellular signal-regulated kinase (ERK1/2, Akt, and nuclear factor (NF-κB phosphorylation. Taken together, oligo-fucoidan supplementation might reduce proliferation of PDGF-treated ASMCs through the suppression of ERK1/2 and Akt phosphorylation and NF-κB activation. The results provide basis for future animal experiments and human trials.

  9. Enhanced adhesion and proliferation of human umbilical vein endothelial cells on conductive PANI-PCL fiber scaffold by electrical stimulation.

    Science.gov (United States)

    Li, Yumei; Li, Xiang; Zhao, Rui; Wang, Chuying; Qiu, Fangping; Sun, Bolun; Ji, He; Qiu, Ju; Wang, Ce

    2017-03-01

    Recently, electrically conductive biomaterial scaffolds have shown great potential in tissue regeneration. Herein, we reported an electrically conductive polyaniline (PANI) coated poly(ε-caprolactone) (PCL) electrospun micron-fiber scaffold for the enhanced attachment and proliferation of human umbilical vein endothelial cells (HUVECs) under electrical stimulation conditions. After the O2 plasma treatment toward PCL electrospun fiber, PANI could be polymerized onto their surfaces successfully. The obtained PANI-PCL fibers were characterized by SEM observations, FT-IR spectra, XPS analysis, and water contact angle measurement. The mechanical tests indicated that the fibers could satisfy the practical vascular scaffold requirements. The conductivity of the PANI-PCL fibers was 6.71×10(-3)S/cm which could provide a conductive in-vitro platform to study the effect of electrical stimulation on HUVECs proliferation. When PANI-coated PCL fibers were compared with PCL fibers, HUVECs exhibited highly enhanced adhesion and viability, especially under electrical stimulation (ES) of 200, 300, and 400mV/cm. Proliferation of HUVECs on PANI-PCL fibers was strongly dependent on electrical stimulation intensity. The results showed new insights into conductive scaffolds for vascular tissue engineering. Copyright © 2016. Published by Elsevier B.V.

  10. Low power laser irradiation stimulates cell proliferation via proliferating cell nuclear antigen and Ki-67 expression during tissue repair

    Science.gov (United States)

    Prabhu, Vijendra; Rao, Bola Sadashiva Satish; Mahato, Krishna Kishore

    2015-03-01

    Low power laser irradiation (LPLI) is becoming an increasingly popular and fast growing therapeutic modality in dermatology to treat various ailments without any reported side effects. In the present study an attempt was made to investigate the proliferative potential of red laser light during tissue repair in Swiss albino mice. To this end, full thickness excisional wounds of diameter 15 mm created on mice were exposed to single dose of Helium-Neon laser (632.8 nm; 7 mW; 4.02 mWcm-2; Linear polarization) at 2 Jcm-2 and 10 Jcm-2 along with un-illuminated controls. The granulation tissues from all the respective experimental groups were harvested on day 10 post-wounding following euthanization. Subsequently, tissue regeneration potential of these laser doses under study were evaluated by monitoring proliferating cell nuclear antigen and Ki-67 following the laser treatment and comparing it with the un-illuminated controls. The percentages of Ki-67 or PCNA positive cells were determined by counting positive nuclei (Ki-67/PCNA) and total nuclei in five random fields per tissue sections. Animal wounds treated with single exposure of the 2 Jcm-2 indicated significant elevation in PCNA (Ptested experimental groups as evidenced by the microscopy results in the study. In summary, the findings of the present study have clearly demonstrated the regulation of cell proliferation by LPLI via PCNA and Ki-67 expression during tissue regeneration.

  11. Alkylglycerols modulate the proliferation and differentiation of non-specific agonist and specific antigen-stimulated splenic lymphocytes.

    Directory of Open Access Journals (Sweden)

    Linxi Qian

    Full Text Available Alkylglycerols (AKGs are ether-linked glycerols derived from shark liver oil and found in small amounts in human milk. Previous studies showed that oral AKGs administration significantly increased the immune response in mice. The aim of the present study was to investigate the in vitro immunomodulatory effect of AKGs on stimulating splenic lymphocyte responses. C57BL/6 mice were immunized with hepatitis B surface antigen (HBsAg. Splenic B cells were purified and stimulated with anti-BCR and anti-CD38. Meanwhile, splenic CD4+ T cells were purified and stimulated with anti-CD3 and anti-CD28. For antigen specific stimulation, the purified CD4+ T cells were cocultured with HBsAg -pulsed dendritic cells. The stimulated lymphocytes were treated with different concentrations of AKGs. The cell proliferation was assessed by [3H]-thymidine incorporation assay. The maturation of B cells was assessed by examining the germline (GL transcription of IgG (γ1 mRNA expression, and the surface expressions of CD80/CD86 markers were examined by flow cytometry analysis. Th1/Th2 polarity was assessed by T-BET (Th1/GATA-3 (Th2 flow cytometry assay and by characteristic cytokines ELISA assay (TNF-α and IFN-γ for Th1; IL-4 and IL-10 for Th2. It was found that AKGs significantly increased the BCR/CD38 -stimulated B cell proliferation. The T cell proliferation in response to CD3/CD28 or specific antigen stimulation was also increased by AKGs. The transcriptional level of IgG (γ1 and the expressions of CD80/CD86 molecules were markedly increased by AKGs in BCR/CD38 -stimulated B cells. Meanwhile, the results showed that AKGs increased the expression of T-BET transcriptional factor and the production of Th1 cytokines (TNF-α and IFN-γ upon CD3/CD28 stimulation; whereas, levels of Th2 cytokines (IL-4 and IL-10 were decreased by AKGs. Our study demonstrated that AKGs can modulate immune responses by boosting the proliferation and maturation of murine lymphocytes in vitro.

  12. Hypoxia-inducible factor-1 (HIF-1) is involved in the regulation of hypoxia-stimulated expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and MCP-5 (Ccl12) in astrocytes

    OpenAIRE

    Mojsilovic-Petrovic Jelena; Callaghan Debbie; Cui Hong; Dean Clare; Stanimirovic Danica B; Zhang Wandong

    2007-01-01

    Abstract Background Neuroinflammation has been implicated in various brain pathologies characterized by hypoxia and ischemia. Astroglia play an important role in the initiation and propagation of hypoxia/ischemia-induced inflammation by secreting inflammatory chemokines that attract neutrophils and monocytes into the brain. However, triggers of chemokine up-regulation by hypoxia/ischemia in these cells are poorly understood. Hypoxia-inducible factor-1 (HIF-1) is a dimeric transcriptional fact...

  13. Conducting cryogel scaffold as a potential biomaterial for cell stimulation and proliferation.

    Science.gov (United States)

    Vishnoi, Tanushree; Kumar, Ashok

    2013-02-01

    The aim of the study was to demonstrate the potential of the cryogelation technique for the synthesis of the conducting cryogel scaffolds which would encompass the advantages of the cryogel matrix, like the mechanical strength and interconnected porous network as well as the conductive properties of the incorporated conducting polymeric material, polypyrrole. The cryogels were synthesized using different combinations of oxidizing agents and surfactants like, sodium dodecyl sulfate (SDS)/ammonium persulfate (APS), SDS/iron chloride (FeCl(3)), cetyl trimethyl ammonium bromide (CTAB)/APS, and CTAB/FeCl(3). The synthesized gels were characterized by scanning electron microscopic analysis for morphology, Fourier transform infrared spectroscopy for analyzing the presence of the polypyrrole (0.5-4 %) as nano-fillers in the gel. It was observed that the presence of these nano-fillers increased the swelling ratio by approximately 50 %. The synthesized conducting cryogels displayed high stress bearing capacity without being deformed as analysed by rheological measurements. The degradation studies showed 12-15 % degradation in 4 weeks time. In vitro studies with conducting and non-conducting cryogel scaffold were carried out to optimize the stimulation conditions for the two cell lines, neuro2a and cardiac muscle C2C12. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed approximately 25 and 15 % increase in the cell proliferation rate for neuro2a and C2C12 cell line, respectively. This was observed at a specific voltage of 100 mV and 2 V, for a specified duration of 2 h and 1 min, respectively for the conducting scaffold as compared to the control. This can play an important role in tissue engineering applications for cell lines where acquiring a high cell number and functionality is desired.

  14. Tumor Necrosis Factor-Alpha and the ERK Pathway Drive Chemerin Expression in Response to Hypoxia in Cultured Human Coronary Artery Endothelial Cells

    Science.gov (United States)

    Chua, Su-Kiat; Shyu, Kou-Gi; Lin, Yuh-Feng; Lo, Huey-Ming; Wang, Bao-Wei

    2016-01-01

    Background Chemerin, a novel adipokine, plays a role in the inflammation status of vascular endothelial cells. Hypoxia causes endothelial-cell proliferation, migration, and angiogenesis. This study was aimed at evaluating the protein and mRNA expression of chemerin after exposure of human coronary artery endothelial cells (HCAECs) to hypoxia. Methods and Results Cultured HCAECs underwent hypoxia for different time points. Chemerin protein levels increased after 4 h of hypoxia at 2.5% O2, with a peak of expression of tumor necrosis factor-alpha (TNF-alpha) at 1 h. Both hypoxia and exogenously added TNF-alpha during normoxia stimulated chemerin expression, whereas an ERK inhibitor (PD98059), ERK small interfering RNA (siRNA), or an anti-TNF-alpha antibody attenuated the chemerin upregulation induced by hypoxia. A gel shift assay indicated that hypoxia induced an increase in DNA-protein binding between the chemerin promoter and transcription factor SP1. A luciferase assay confirmed an increase in transcriptional activity of SP1 on the chemerin promoter during hypoxia. Hypoxia significantly increased the tube formation and migration of HCAECs, whereas PD98059, the anti-TNF-alpha antibody, and chemerin siRNA each attenuated these effects. Conclusion Hypoxia activates chemerin expression in cultured HCAECs. Hypoxia-induced chemerin expression is mediated by TNF-alpha and at least in part by the ERK pathway. Chemerin increases early processes of angiogenesis by HCAECs after hypoxic treatment. PMID:27792771

  15. Effects on the rabbit carotid body of stimulation by almitrine, natural high altitude, and experimental normobaric hypoxia.

    Science.gov (United States)

    Smith, P; Heath, D; Fitch, R; Hurst, G; Moore, D; Weitzenblum, E

    1986-06-01

    Rabbits were given intraperitoneal injections of almitrine in ascending doses for 5 weeks. They were compared with a control group and with a group of rabbits which had been exposed from birth to the natural hypobaric hypoxia found at Cerro de Pasco (433 m) in the Peruvian Andes. A further group of animals was placed in an experimental normobaric chamber for either 3 or 6 months to subject them to the same degree of hypoxia as that occurring in Cerro. The carotid bodies of the rabbits in all these groups were processed for light and electron microscopy, and examined both qualitatively and quantitatively. The carotid bodies in the group given almitrine showed no changes in their size or in the population of their glomic cells when compared with controls. In contrast, the carotid bodies of Peruvian rabbits were greatly enlarged with a disproportionate increase in the population of the light variant of chief cell. Rabbits from the hypoxic chamber also had enlarged carotid bodies but those killed after 3 months showed an increase in the dark variant of chief cell, whereas after 6 months this cell was reduced in number. There was also intense cytoplasmic vacuolation. Election microscopy confirmed these changes and revealed that dark cells had larger, more pleomorphic granules than the light variant. Vacuolation of the granules in light cells was most pronounced in Peruvian rabbits, but was uncommon in animals exposed to hypoxia for 3 months. We suggest that the dark cell responds to the early stages of hypoxia but later matures into the light variant of chief cell.

  16. Glycogen synthesis is induced in hypoxia by the hypoxia-inducible factor and promotes cancer cell survival

    Directory of Open Access Journals (Sweden)

    Joffrey ePelletier

    2012-02-01

    Full Text Available The hypoxia-inducible factor 1 (HIF-1, in addition to genetic and epigenetic changes, is largely responsible for alterations in cell metabolism in hypoxic tumor cells. This transcription factor not only favors cell proliferation through the metabolic shift from oxidative phosphorylation to glycolysis and lactic acid production but also stimulates nutrient supply by mediating adaptive survival mechanisms. In this study we showed that glycogen synthesis is enhanced in non-cancer and cancer cells when exposed to hypoxia, resulting in a large increase in glycogen stores. Furthermore, we demonstrated that the mRNA and protein levels of the first enzyme of glycogenesis, phosphoglucomutase1 (PGM1, were increased in hypoxia. We showed that induction of glycogen storage as well as PGM1 expression were dependent on HIF-1 and HIF-2. We established that hypoxia-induced glycogen stores are rapidly mobilized in cells that are starved of glucose. Glycogenolysis allows these hypoxia-preconditioned cells to confront and survive glucose deprivation. In contrast normoxic control cells exhibit a high rate of cell death following glucose removal. These findings point to the important role of hypoxia and HIF in inducing mechanisms of rapid adaptation and survival in response to a decrease in oxygen tension. We propose that a decrease in pO2 acts as an alarm that prepares the cells to face subsequent nutrient depletion and to survive.

  17. Stimulation of α1a adrenergic receptors induces cellular proliferation or antiproliferative hypertrophy dependent solely on agonist concentration.

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    Beilei Lei

    Full Text Available Stimulation of α1aAdrenergic Receptors (ARs is known to have anti-proliferative and hypertrophic effects; however, some studies also suggests this receptor can increase cell proliferation. Surprisingly, we find the α1aAR expressed in rat-1 fibroblasts can produce either phenotype, depending exclusively on agonist concentration. Stimulation of the α1aAR by high dose phenylephrine (>10(-7 M induces an antiproliferative, hypertrophic response accompanied by robust and extended p38 activation. Inhibition of p38 with SB203580 prevented the antiproliferative response, while inhibition of Erk or Jnk had no effect. In stark contrast, stimulation of the α1aAR with low dose phenylephrine (∼10(-8 M induced an Erk-dependent increase in cellular proliferation. Agonist-induced Erk phosphorylation was preceded by rapid FGFR and EGFR transactivation; however, only EGFR inhibition blocked Erk activation and proliferation. The general matrix metalloprotease inhibitor, GM6001, blocked agonist induced Erk activation within seconds, strongly suggesting EGFR activation involved extracellular triple membrane pass signaling. Erk activation required little Ca(2+ release and was blocked by PLCβ or PKC inhibition but not by intracellular Ca(2+ chelation, suggesting Ca(2+ independent activation of novel PKC isoforms. In contrast, Ca(2+ release was essential for PI3K/Akt activation, which was acutely maximal at non-proliferative doses of agonist. Remarkably, our data suggests EGFR transactivation leading to Erk induced proliferation has the lowest activation threshold of any α1aAR response. The ability of α1aARs to induce proliferation are discussed in light of evidence suggesting antagonistic growth responses reflect native α1aAR function.

  18. Inhibition of hypoxia-induced cyclooxygenase-2 by Korean Red Ginseng is dependent on peroxisome proliferator-activated receptor gamma

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    Heewon Song

    2017-07-01

    Discussion: Our results show that KRG inhibition of hypoxia-induced COX-2 expression and cell invasion is dependent on PPARγ activation, supporting the therapeutic potential for suppression of inflammation under hypoxia. Further studies are required to demonstrate whether KRG activates directly PPARγ and to identify the constituents responsible for this activity.

  19. Hypoxia-inducible factors and RAB22A mediate formation of microvesicles that stimulate breast cancer invasion and metastasis.

    Science.gov (United States)

    Wang, Ting; Gilkes, Daniele M; Takano, Naoharu; Xiang, Lisha; Luo, Weibo; Bishop, Corey J; Chaturvedi, Pallavi; Green, Jordan J; Semenza, Gregg L

    2014-08-05

    Extracellular vesicles such as exosomes and microvesicles (MVs) are shed by cancer cells, are detected in the plasma of cancer patients, and promote cancer progression, but the molecular mechanisms regulating their production are not well understood. Intratumoral hypoxia is common in advanced breast cancers and is associated with an increased risk of metastasis and patient mortality that is mediated in part by the activation of hypoxia-inducible factors (HIFs). In this paper, we report that exposure of human breast cancer cells to hypoxia augments MV shedding that is mediated by the HIF-dependent expression of the small GTPase RAB22A, which colocalizes with budding MVs at the cell surface. Incubation of naïve breast cancer cells with MVs shed by hypoxic breast cancer cells promotes focal adhesion formation, invasion, and metastasis. In breast cancer patients, RAB22A mRNA overexpression in the primary tumor is associated with decreased overall and metastasis-free survival and, in an orthotopic mouse model, RAB22A knockdown impairs breast cancer metastasis.

  20. An essential role for Gα(i2) in Smoothened-stimulated epithelial cell proliferation in the mammary gland.

    Science.gov (United States)

    Villanueva, Hugo; Visbal, Adriana P; Obeid, Nadine F; Ta, Andrew Q; Faruki, Adeel A; Wu, Meng-Fen; Hilsenbeck, Susan G; Shaw, Chad A; Yu, Peng; Plummer, Nicholas W; Birnbaumer, Lutz; Lewis, Michael T

    2015-09-15

    Hedgehog (Hh) signaling is critical for organogenesis, tissue homeostasis, and stem cell maintenance. The gene encoding Smoothened (SMO), the primary effector of Hh signaling, is expressed aberrantly in human breast cancer, as well as in other cancers. In mice that express a constitutively active form of SMO that does not require Hh stimulation in mammary glands, the cells near the transgenic cells proliferate and participate in hyperplasia formation. Although SMO is a seven-transmembrane receptor like G protein-coupled receptors (GPCRs), SMO-mediated activation of the Gli family of transcription factors is not known to involve G proteins. However, data from Drosophila and mammalian cell lines indicate that SMO functions as a GPCR that couples to heterotrimeric G proteins of the pertussis toxin (PTX)-sensitive Gαi class. Using genetically modified mice, we demonstrated that SMO signaling through G proteins occurred in the mammary gland in vivo. SMO-induced stimulation of proliferation was PTX-sensitive and required Gαi2, but not Gαi1, Gαi3, or activation of Gli1 or Gli2. Our findings show that activated SMO functions as a GPCR to stimulate proliferation in vivo, a finding that may have clinical importance because most SMO-targeted agents have been selected based largely on their ability to block Gli-mediated transcription.

  1. Perinatal hypoxia-ischemia reduces α 7 nicotinic receptor expression and selective α 7 nicotinic receptor stimulation suppresses inflammation and promotes microglial Mox phenotype.

    Science.gov (United States)

    Hua, Sansan; Ek, C Joakim; Mallard, Carina; Johansson, Maria E

    2014-01-01

    Inflammation plays a central role in neonatal brain injury. During brain inflammation the resident macrophages of the brain, the microglia cells, are rapidly activated. In the periphery, α 7 nicotinic acetylcholine receptors ( α 7R) present on macrophages can regulate inflammation by suppressing cytokine release. In the current study we investigated α 7R expression in neonatal mice after hypoxia-ischemia (HI). We further examined possible anti-inflammatory role of α 7R stimulation in vitro and microglia polarization after α 7R agonist treatment. Real-time PCR analysis showed a 33% reduction in α 7R expression 72 h after HI. Stimulation of primary microglial cells with LPS in combination with increasing doses of the selective α 7R agonist AR-R 17779 significantly attenuated TNF α release and increased α 7R transcript in microglial cells. Gene expression of M1 markers CD86 and iNOS, as well as M2 marker CD206 was not influenced by LPS and/or α 7R agonist treatment. Further, Mox markers heme oxygenase (Hmox1) and sulforedoxin-1 (Srx1) were significantly increased, suggesting a polarization towards the Mox phenotype after α 7R stimulation. Thus, our data suggest a role for the α 7R also in the neonatal brain and support the anti-inflammatory role of α 7R in microglia, suggesting that α 7R stimulation could enhance the polarization towards a reparative Mox phenotype.

  2. Perinatal Hypoxia-Ischemia Reduces α7 Nicotinic Receptor Expression and Selective α7 Nicotinic Receptor Stimulation Suppresses Inflammation and Promotes Microglial Mox Phenotype

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    Sansan Hua

    2014-01-01

    Full Text Available Inflammation plays a central role in neonatal brain injury. During brain inflammation the resident macrophages of the brain, the microglia cells, are rapidly activated. In the periphery, α7 nicotinic acetylcholine receptors (α7R present on macrophages can regulate inflammation by suppressing cytokine release. In the current study we investigated α7R expression in neonatal mice after hypoxia-ischemia (HI. We further examined possible anti-inflammatory role of α7R stimulation in vitro and microglia polarization after α7R agonist treatment. Real-time PCR analysis showed a 33% reduction in α7R expression 72 h after HI. Stimulation of primary microglial cells with LPS in combination with increasing doses of the selective α7R agonist AR-R 17779 significantly attenuated TNFα release and increased α7R transcript in microglial cells. Gene expression of M1 markers CD86 and iNOS, as well as M2 marker CD206 was not influenced by LPS and/or α7R agonist treatment. Further, Mox markers heme oxygenase (Hmox1 and sulforedoxin-1 (Srx1 were significantly increased, suggesting a polarization towards the Mox phenotype after α7R stimulation. Thus, our data suggest a role for the α7R also in the neonatal brain and support the anti-inflammatory role of α7R in microglia, suggesting that α7R stimulation could enhance the polarization towards a reparative Mox phenotype.

  3. Correlation between expressions of hypoxia -inducible factor (HIF-1α, blood vessels density, cell proliferation, and apoptosis intensity in canine fibromas and fibrosarcomas

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    Madej Janusz A.

    2014-03-01

    Full Text Available The study aimed to demonstrate the expression of hypoxia-inducible factor (HIF-1α in soft tissue mesenchymal tumours (fibroma and fibrosarcoma in dogs. An attempt was made to correlate the obtained results with density of blood vessels (expression of von Willebrand Factor, vWF, expression of Ki-67 proliferation antigen, and with intensity of apoptosis in studied tumours. The study was performed on paraffin sections of 15 fibromas and 40 fibrosarcomas sampled from 55 female dogs aged 6 to 16 years. Immunohistochemical staining against HIF-1α, vWF, and Ki-67 was performed. Apoptosis was detected with the use of TUNEL reaction. A significantly higher HIF-1α expression was noted in fibrosarcomas in comparison to fibromas (P < 0.0001. HIF-1α expression in fibromas manifested strong positive correlation with tumour vascularity (r = 0.67, P = 0.007. Moreover, HIF-1α expression in fibrosarcomas manifested a moderate positive correlation with tumour malignancy grade (r = 0.44, P = 0.004, tumour vascularity (r = 0.52, P < 0.001, Ki-67 antigen expression (r = 0.42; P = 0.007, and TUNELpositive cells (r = 0.37, P = 0.017. Expression of HIF-1α was detected in 86.7% of fibroma type tumours and in 100% of fibrosarcomas. In all studied tumours expression of HIF-1α manifested positive correlation with the density of blood vessels, and in fibrosarcomas it correlated also with malignancy grade, intensity of Ki-67 expression, and with intensity of apoptosis in tumour cells.

  4. Effects of low- and high-frequency repetitive magnetic stimulation on neuronal cell proliferation and growth factor expression: A preliminary report.

    Science.gov (United States)

    Lee, Ji Yong; Park, Hyung Joong; Kim, Ji Hyun; Cho, Byung Pil; Cho, Sung-Rae; Kim, Sung Hoon

    2015-09-14

    Repetitive magnetic stimulation is a neuropsychiatric and neurorehabilitation tool that can be used to investigate the neurobiology of sensory and motor functions. Few studies have examined the effects of repetitive magnetic stimulation on the modulation of neurotrophic/growth factors and neuronal cells in vitro. Therefore, the current study examined the differential effects of repetitive magnetic stimulation on neuronal cell proliferation as well as various growth factor expression. Immortalized mouse neuroblastoma cells were used as the cell model in this study. Dishes of cultured cells were randomly divided into control, sham, low-frequency (0.5Hz, 1Tesla) and high-frequency (10Hz, 1Tesla) groups (n=4 dishes/group) and were stimulated for 3 days. Expression of neurotrophic/growth factors, Akt and Erk was investigated by Western blotting analysis 3 days after repetitive magnetic stimulation. Neuroblastoma cell proliferation was determined with a cell counting assay. There were differences in cell proliferation based on stimulus frequency. Low-frequency stimulation did not alter proliferation relative to the control, while high-frequency stimulation elevated proliferation relative to the control group. The expression levels of brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3) and platelet-derived growth factor (PDGF) were elevated in the high-frequency magnetic stimulation group. Akt and Erk expression was also significantly elevated in the high-frequency stimulation group, while low-frequency stimulation decreased the expression of Akt and Erk compared to the control. In conclusion, we determined that different frequency magnetic stimulation had an influence on neuronal cell proliferation via regulation of Akt and ERK signaling pathways and the expression of growth factors such as BDNF, GDNF, NT-3 and PDGF. These findings represent a promising opportunity to gain insight into how different

  5. β-adrenergic response modulated by κ-opioid receptor stimulation is attenuated in the cardiomyocytes of rats following chronic hypoxia

    Institute of Scientific and Technical Information of China (English)

    裴建明; 毕辉; 王跃民; 朱妙章; 周京军; 朱运龙

    2003-01-01

    Objective: To study cross-talk between β-opioid receptor and β-adrenoceptor through determination of the intracellular calcium ([Ca2+]i) and cAMP responses in ventricular myocytes of rats subjected to chronic hypoxia for 4 weeks.Methods: Electrically-induced [Ca2+]i transient was measured in single right ventricular myocytes isolated from hearts of chronically hypoxic rats and the age-matched normoxic rats, by using a spectrofluorometric method.Results: β-adrenoceptor stimulation with isoproterenol increased the electrically-induced [Ca2+]i transient and cAMP in myocytes of normoxic rats.U50,488H, a selective β-opioid receptor agonist, at dose (1 μmol/L) which itself had no effect on the [Ca2+]i transient and cAMP, significantly inhibited the effect of isoproterenol.This inhibition was completely abolished in the presence of nor-BNI, a selective κ-opioid receptor antagonist.In the ventricular myocytes of chronically hypoxic rats, the inhibition of U50,488H on the increased [Ca2+]i transient and cAMP with isoproterenol was blunted.Conclusion: Results indicate that the cross-talk between the κ-opioid receptor and β-adrenoceptor is attenuated in the right ventricular myocytes of chronically hypoxic rat.This may be a self-protective mechanism of the heart following chronic hypoxia, which prevents the further decrease of the cardiac function.

  6. Homeostatic 'bystander' proliferation of human peripheral blood B cells in response to polyclonal T-cell stimulation in vitro.

    Science.gov (United States)

    Jasiulewicz, Aleksandra; Lisowska, Katarzyna A; Pietruczuk, Krzysztof; Frąckowiak, Joanna; Fulop, Tamas; Witkowski, Jacek M

    2015-11-01

    The mechanisms of maintenance of adequate numbers of B lymphocytes and of protective levels of immunoglobulins in the absence of antigenic (re)stimulation remain not fully understood. Meanwhile, our results presented here show that both peripheral blood naive and memory B cells can be activated strongly and non-specifically (in a mitogen-like fashion) in 5-day in vitro cultures of anti-CD3- or concanavalin A (Con A)-stimulated peripheral blood mononuclear cells of healthy people. This polyclonal, bystander activation of the B cells includes multiple divisions of most of them (assessed here by the flow cytometric technique of dividing cell tracking) and significant antibody [immunoglobulin M (IgM) and IgG] secretion. Observed proliferation of the CD19(+) B cells depends on contact with stimulated T helper (Th) cells (via CD40-CD40L interaction) and on the response of B cells to secreted interleukins IL-5, IL-10 and IL-4, and is correlated with the levels of these Th-derived molecules, while it does not involve the ligation of the BCR/CD19 complex. We suggest that the effect might reflect the situation occurring in vivo as the homeostatic proliferation of otherwise non-stimulated, peripheral B lymphocytes, providing an always ready pool for efficient antibody production to any new (or cognate) antigen challenge.

  7. Hypoxia, leptin, and vascular endothelial growth factor stimulate vascular endothelial cell differentiation of human adipose tissue-derived stem cells.

    Science.gov (United States)

    Bekhite, Mohamed M; Finkensieper, Andreas; Rebhan, Jennifer; Huse, Stephanie; Schultze-Mosgau, Stefan; Figulla, Hans-Reiner; Sauer, Heinrich; Wartenberg, Maria

    2014-02-15

    The plasticity of human adipose tissue-derived stem cells (hASCs) is promising, but differentiation in vitro toward endothelial cells is poorly understood. Flow cytometry demonstrated that hASCs isolated from excised fat tissue were positive for CD29, CD44, CD70, CD90, CD105, and CD166 and negative for the endothelial marker CD31, and the hematopoietic cell markers CD34 and CD133. hASCs differentiated into adipocytes after cultivation in adipogenic medium. Exposure of hASCs for 10 days under hypoxia (3% oxygen) in combination with leptin increased the percentage of CD31(+) endothelial cells as well as CD31, VE-Cadherin, Flk-1, Tie2, von Willebrand factor, and endothelial cell nitric oxide synthase mRNA expression. This was enhanced on co-incubation of vascular endothelial growth factor (VEGF) and leptin, whereas VEGF alone was not sufficient. Moreover, hASCs cultured on a matrigel surface under hypoxia/VEGF/leptin, showed a stable branching network. Hypoxic conditions significantly decreased apoptosis as evaluated by cleaved caspase-3, and increased prolyl hydroxylase domain 3 mRNA expression. Hypoxia increased expression of VEGF as well as leptin transcripts, which were significantly inhibited on co-incubation with either VEGF or leptin or a combination of both. Furthermore, leptin treatment of hypoxic cells increased the expression of the long/signaling form of the leptin receptor (ObRL), which was augmented on co-incubation with VEGF. The observed endothelial differentiation was dependent on the Akt pathway, as co-administration with Akt inhibitor abolished the observed effects. In conclusion, our data demonstrate that hASCs can be efficiently differentiated to endothelial cells by mimicking the hypoxic and pro-angiogenic microenvironment of adipose tissue.

  8. Repetitive magnetic stimulation promotes neural stem cells proliferation by upregulating MiR-106b in vitro.

    Science.gov (United States)

    Liu, Hua; Han, Xiao-hua; Chen, Hong; Zheng, Cai-xia; Yang, Yi; Huang, Xiao-lin

    2015-10-01

    Neural stem cells (NSCs) proliferation can be influenced by repetitive transcranial magnetic stimulation (rTMS) in vivo via microRNA-106b-25 cluster, but the underlying mechanisms are poorly understood. This study investigated the involvement of microRNA-106b-25 cluster in the proliferation of NSCs after repetitive magnetic stimulation (rMS) in vitro. NSCs were stimulated by rMS (200/400/600/800/1000 pulses per day, with 10 Hz frequency and 50% maximum machine output) over a 3-day period. NSCs proliferation was detected by using ki-67 and EdU staining. Ki-67, p21, p57, cyclinD1, cyclinE, cyclinA, cdk2, cdk4 proteins and miR-106b, miR-93, miR-25 mRNAs were detected by Western blotting and qRT-PCR, respectively. The results showed that rMS could promote NSCs proliferation in a dose-dependent manner. The proportions of ki-67+ and Edu+ cells in 1000 pulses group were 20.65% and 4.00%, respectively, significantly higher than those in control group (9.25%, 2.05%). The expression levels of miR-106b and miR-93 were significantly upregulated in 600-1000 pulses groups compared with control group (Pp21 protein were decreased significantly in 800/1000 pulses groups, and those of cyclinD1, cyclinA, cyclinE, cdk2 and cdk4 were obviously increased after rMS as compared with control group (Pp21/cdks/cyclins pathway was involved in the process.

  9. The selection of light emitting diode irradiation parameters for stimulation of human mesenchymal stem cells proliferation

    Science.gov (United States)

    Lewandowski, Rafał; Trafny, ElŻbieta A.; Stepińska, Małgorzata; Gietka, Andrzej; Kotowski, Paweł; Dobrzyńska, Monika; Łapiński, Mariusz P.

    2016-12-01

    Human mesenchymal stem cells (hMSCs) with their vast differentiation potential are very useful for cell-based regenerative medicine. To achieve sufficient numbers of cells for tissue engineering, many different methods have been used to reach the effective increase of cell proliferation. Low-energy red light provided by light emitting diodes (LEDs) have been recently introduced as a method that promoted biomodulation and proliferation of hMSCs in vitro. The purpose of this study was to find the optimum stimulatory dosimetric parameters of LED (630 nm) irradiation on the hMSCs proliferation. The energy density was 2, 3, 4, 10, 20 J/cm2 and the power density used was 7, 17 or 30 mW/cm2. Human MSCs were irradiated with single or triple exposures daily at room temperature and the cell proliferation rate was evaluated during nine days after irradiation. The results showed that after irradiation 4 J/cm2 and 17 mW/cm2 at a single dose the proliferation rate of hMSCs increased on day 5 and 9 (13% and 7%, respectively) when compared to nonirradiated cells. However, triple LED irradiation under the same parameters resulted in the decline in the cell proliferation rate on day 5, but the proliferation rate was at the same level on day 9, when compared with the cell proliferation after irradiation with a single dose. The effect of a single dose irradiation with 4 J/cm2 and 17 mW/cm2 on the proliferation of cells was the highest when the cells were irradiated in phosphate-buffered saline (PBS) instead of MSCGM culture medium.

  10. Cyclin C stimulates β-cell proliferation in rat and human pancreatic β-cells

    OpenAIRE

    2015-01-01

    Activation of pancreatic β-cell proliferation has been proposed as an approach to replace reduced functional β-cell mass in diabetes. Quiescent fibroblasts exit from G0 (quiescence) to G1 through pRb phosphorylation mediated by cyclin C/cdk3 complexes. Overexpression of cyclin D1, D2, D3, or cyclin E induces pancreatic β-cell proliferation. We hypothesized that cyclin C overexpression would induce β-cell proliferation through G0 exit, thus being a potential therapeutic target to recover funct...

  11. Effect of epidermal growth factor on follicle-stimulating hormone-induced proliferation of granulosa cells from chicken prehierarchical follicles

    Institute of Scientific and Technical Information of China (English)

    Jin-xing LIN; Yu-dong JIA; Cai-qiao ZHANG

    2011-01-01

    The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors,including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF).In this study,the stagespecific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens.Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles,including the large white follicle (LWF) and small yellow follicle (SYF),and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle.SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection.Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action.Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1-100 ng/ml).This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis.Furthermore,EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR,FSH receptor,and the cell cycle-regulating genes (cyclins D1 and E1,cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA.However,the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478.In conclusion,EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles.These expressions thus stimulated follicular growth before selection in the egg-laying chicken.

  12. Hypothermia reduces VEGF-165 expression, but not osteogenic differentiation of human adipose stem cells under hypoxia

    Science.gov (United States)

    Bakker, Astrid D.; Hogervorst, Jolanda M. A.; Nolte, Peter A.; Klein-Nulend, Jenneke

    2017-01-01

    Cryotherapy is successfully used in the clinic to reduce pain and inflammation after musculoskeletal damage, and might prevent secondary tissue damage under the prevalent hypoxic conditions. Whether cryotherapy reduces mesenchymal stem cell (MSC) number and differentiation under hypoxic conditions, causing impaired callus formation is unknown. We aimed to determine whether hypothermia modulates proliferation, apoptosis, nitric oxide production, VEGF gene and protein expression, and osteogenic/chondrogenic differentiation of human MSCs under hypoxia. Human adipose MSCs were cultured under hypoxia (37°C, 1% O2), hypothermia and hypoxia (30°C, 1% O2), or control conditions (37°C, 20% O2). Total DNA, protein, nitric oxide production, alkaline phosphatase activity, gene expression, and VEGF protein concentration were measured up to day 8. Hypoxia enhanced KI67 expression at day 4. The combination of hypothermia and hypoxia further enhanced KI67 gene expression compared to hypoxia alone, but was unable to prevent the 1.2-fold reduction in DNA amount caused by hypoxia at day 4. Addition of hypothermia to hypoxic cells did not alter the effect of hypoxia alone on BAX-to-BCL-2 ratio, alkaline phosphatase activity, gene expression of SOX9, COL1, or osteocalcin, or nitric oxide production. Hypothermia decreased the stimulating effect of hypoxia on VEGF-165 gene expression by 6-fold at day 4 and by 2-fold at day 8. Hypothermia also decreased VEGF protein expression under hypoxia by 2.9-fold at day 8. In conclusion, hypothermia decreased VEGF-165 gene and protein expression, but did not affect differentiation, or apoptosis of MSCs cultured under hypoxia. These in vitro results implicate that hypothermia treatment in vivo, applied to alleviate pain and inflammation, is not likely to harm early stages of callus formation. PMID:28166273

  13. Hypoxia Room

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypoxia Room is a 8x8x8 ft. clear vinyl plastic and aluminum frame construction enclosure located within USAREIM laboratory 028. The Hypoxia Room (manufactured...

  14. Hypoxia Room

    Data.gov (United States)

    Federal Laboratory Consortium — The Hypoxia Room is a 8x8x8 ft. clear vinyl plastic and aluminum frame construction enclosure located within USAREIM laboratory 028. The Hypoxia Room (manufactured...

  15. Helium-neon laser irradiation stimulates migration and proliferation in melanocytes and induces repigmentation in segmental-type vitiligo.

    Science.gov (United States)

    Yu, Hsin-Su; Wu, Chieh-Shan; Yu, Chia-Li; Kao, Ying-Hsien; Chiou, Min-Hsi

    2003-01-01

    Low-energy helium-neon lasers (632.8 nm) have been employed in a variety of clinical treatments including vitiligo management. Light-mediated reaction to low-energy laser irradiation is referred to as biostimulation rather than a thermal effect. This study sought to determine the theoretical basis and clinical evidence for the effectiveness of helium-neon lasers in treating vitiligo. Cultured keratinocytes and fibroblasts were irradiated with 0.5-1.5 J per cm2 helium-neon laser radiation. The effects of the helium-neon laser on melanocyte growth and proliferation were investigated. The results of this in vitro study revealed a significant increase in basic fibroblast growth factor release from both keratinocytes and fibroblasts and a significant increase in nerve growth factor release from keratinocytes. Medium from helium-neon laser irradiated keratinocytes stimulated [3H]thymidine uptake and proliferation of cultured melanocytes. Furthermore, melanocyte migration was enhanced either directly by helium-neon laser irradiation or indirectly by the medium derived from helium-neon laser treated keratinocytes. Thirty patients with segmental-type vitiligo on the head and/or neck were enrolled in this study. Helium-neon laser light was administered locally at 3.0 J per cm2 with point stimulation once or twice weekly. The percentage of repigmented area was used for clinical evaluation of effectiveness. After an average of 16 treatment sessions, initial repigmentation was noticed. Marked repigmentation (>50%) was observed in 60% of patients with successive treatments. Basic fibroblast growth factor is a putative melanocyte growth factor, whereas nerve growth factor is a paracrine factor for melanocyte survival in the skin. Both nerve growth factor and basic fibroblast growth factor stimulate melanocyte migration. It is reasonable to propose that helium-neon laser irradiation clearly stimulates melanocyte migration and proliferation and mitogen release for melanocyte growth

  16. The role of adrenergic stimulation in maintaining maximum cardiac performance in rainbow trout (Oncorhynchus mykiss) during hypoxia, hyperkalemia and acidosis at 10 degrees C.

    Science.gov (United States)

    Hanson, Linda M; Obradovich, Shannon; Mouniargi, Janet; Farrell, Anthony P

    2006-07-01

    As rainbow trout approach exhaustion during prolonged exercise, they maintain maximum cardiac output despite the fact their venous blood, which bathes the heart, becomes hypoxic, acidotic and hyperkalemic. Because these factors are individually recognized to have detrimental inotropic and chronotropic effects on cardiac performance, we hypothesized that adrenergic stimulation is critical in maintaining maximum cardiac performance under these collectively adverse conditions in vivo. To test this hypothesis, maximum cardiac performance in the presence and absence of maximal adrenergic stimulation was assessed with in situ rainbow trout hearts using relevant hyperkalemic (5.0 mmol l(-1) K+), acidotic (pH 7.5) and hypoxic challenges. With tonic adrenergic stimulation (5.0 nmol l(-1) adrenaline), hearts produced only 44.8+/-14.6% of their normal maximum cardiac output when exposed under normoxic conditions (20 kPa) to the hyperkalemic, acidotic perfusate, indicating that in vivo there was no refuge from cardiac impairment even if venous blood was fully oxygenated. By contrast, maximum adrenergic stimulation (500 nmol l(-1) adrenaline), fully protected maximum cardiac performance under hyperkalemic and acidotic conditions over a wide range of oxygen availability, from normoxia to 2.0 kPa, a venous oxygen tension close to routine values in vivo. Extending the level of hypoxia to 1.3 kPa resulted in a 43.6+/-2.8% decrease in maximum cardiac output, with hearts failing when tested at 1.0 kPa. Our results suggest that adrenergic stimulation of the trout heart is critical in maintaining maximum performance during prolonged swimming tests, and probably during all forms of exhaustive activity and recovery, when venous blood is hyperkalemic, acidotic and hypoxic.

  17. Setae from larvae of the northern processionary moth (Thaumetopoea pinivora, TP) stimulate proliferation of human blood lymphocytes in vitro.

    Science.gov (United States)

    Holm, Göran; Andersson, Margareta; Ekberg, Monica; Fagrell, Bengt; Sjöberg, Jan; Bottai, Matteo; Björkholm, Magnus

    2014-01-01

    Larvae of the Northern pine processionary moth (Thaumetopoea pinivora, TP) carry microscopic needles (setae), which by penetrating skin and mucous membranes, may cause inflammatory/immune derived symptoms in man. In the present study the stimulatory effects of setae on human blood lymphocytes in vitro was investigated. Blood mononuclear cells were separated from venous blood or buffy coat of ten healthy individuals, six previously exposed to setae and four with no known exposure. Lymphoproliferation was measured as uptake of 3H-thymidine. Setae were prepared from TP larvae. Setae and saline setae extracts stimulated proliferation of T-lymphocytes in the presence of monocytic cells. Stimulation was pronounced in cells from persons who had been exposed to setae, and weak in cells from non-exposed donors. Chitin also induced lymphocyte proliferation in most donors, but to a lesser extent and independently of donor's previous exposure to setae. In conclusion, setae contain molecules that in the presence of monocytes activate human T-lymphocytes to proliferation. The antigenic nature of stimulatory molecules was supported by the significantly stronger lymphocyte response in persons previously exposed to setae than in non-exposed donors. The nature of such molecules remains to be defined.

  18. Setae from larvae of the northern processionary moth (Thaumetopoea pinivora, TP stimulate proliferation of human blood lymphocytes in vitro.

    Directory of Open Access Journals (Sweden)

    Göran Holm

    Full Text Available Larvae of the Northern pine processionary moth (Thaumetopoea pinivora, TP carry microscopic needles (setae, which by penetrating skin and mucous membranes, may cause inflammatory/immune derived symptoms in man. In the present study the stimulatory effects of setae on human blood lymphocytes in vitro was investigated. Blood mononuclear cells were separated from venous blood or buffy coat of ten healthy individuals, six previously exposed to setae and four with no known exposure. Lymphoproliferation was measured as uptake of 3H-thymidine. Setae were prepared from TP larvae. Setae and saline setae extracts stimulated proliferation of T-lymphocytes in the presence of monocytic cells. Stimulation was pronounced in cells from persons who had been exposed to setae, and weak in cells from non-exposed donors. Chitin also induced lymphocyte proliferation in most donors, but to a lesser extent and independently of donor's previous exposure to setae. In conclusion, setae contain molecules that in the presence of monocytes activate human T-lymphocytes to proliferation. The antigenic nature of stimulatory molecules was supported by the significantly stronger lymphocyte response in persons previously exposed to setae than in non-exposed donors. The nature of such molecules remains to be defined.

  19. Basic Fibroblast Growth Factor Stimulates the Proliferation of Bone Marrow Mesenchymal Stem Cells in Giant Panda (Ailuropoda melanoleuca.

    Directory of Open Access Journals (Sweden)

    Jun-Jie Wang

    Full Text Available It has been widely known that the giant panda (Ailuropoda melanoleuca is one of the most endangered species in the world. An optimized platform for maintaining the proliferation of giant panda mesenchymal stem cells (MSCs is very necessary for current giant panda protection strategies. Basic fibroblast growth factor (bFGF, a member of the FGF family, is widely considered as a growth factor and differentiation inducer within the stem cell research field. However, the role of bFGF on promoting the proliferation of MSCs derived from giant panda bone marrow (BM has not been reported. In this study, we aimed to investigate the role of bFGF on the proliferation of BM-MSCs derived from giant panda. MSCs were cultured for cell proliferation analysis at 24, 48 and 72 hrs following the addition of bFGF. With increasing concentrations of bFGF, cell numbers gradually increased. This was further demonstrated by performing 3-(4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2-H-tetrazolium bromide (MTT cell proliferation assay, 5-Bromo-2-deoxyUridine (BrdU labeling and cell cycle testing. Furthermore, the percentage of MSCs that were OCT4 positive increased slightly following treatment with 5 ng/ml bFGF. Moreover, we demonstrated that the extracellular signal-regulated kinase (ERK signaling pathway may play an important role in the proliferation of panda MSCs stimulated by bFGF. In conclusion, this study suggests that giant panda BM-MSCs have a high proliferative capacity with the addition of 5 ng/ml bFGF in vitro.

  20. Basic Fibroblast Growth Factor Stimulates the Proliferation of Bone Marrow Mesenchymal Stem Cells in Giant Panda (Ailuropoda melanoleuca).

    Science.gov (United States)

    Wang, Jun-Jie; Liu, Yu-Liang; Sun, Yuan-Chao; Ge, Wei; Wang, Yong-Yong; Dyce, Paul W; Hou, Rong; Shen, Wei

    2015-01-01

    It has been widely known that the giant panda (Ailuropoda melanoleuca) is one of the most endangered species in the world. An optimized platform for maintaining the proliferation of giant panda mesenchymal stem cells (MSCs) is very necessary for current giant panda protection strategies. Basic fibroblast growth factor (bFGF), a member of the FGF family, is widely considered as a growth factor and differentiation inducer within the stem cell research field. However, the role of bFGF on promoting the proliferation of MSCs derived from giant panda bone marrow (BM) has not been reported. In this study, we aimed to investigate the role of bFGF on the proliferation of BM-MSCs derived from giant panda. MSCs were cultured for cell proliferation analysis at 24, 48 and 72 hrs following the addition of bFGF. With increasing concentrations of bFGF, cell numbers gradually increased. This was further demonstrated by performing 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) cell proliferation assay, 5-Bromo-2-deoxyUridine (BrdU) labeling and cell cycle testing. Furthermore, the percentage of MSCs that were OCT4 positive increased slightly following treatment with 5 ng/ml bFGF. Moreover, we demonstrated that the extracellular signal-regulated kinase (ERK) signaling pathway may play an important role in the proliferation of panda MSCs stimulated by bFGF. In conclusion, this study suggests that giant panda BM-MSCs have a high proliferative capacity with the addition of 5 ng/ml bFGF in vitro.

  1. Microenvironmental stiffness enhances glioma cell proliferation by stimulating epidermal growth factor receptor signaling.

    Directory of Open Access Journals (Sweden)

    Vaibhavi Umesh

    Full Text Available The aggressive and rapidly lethal brain tumor glioblastoma (GBM is associated with profound tissue stiffening and genomic lesions in key members of the epidermal growth factor receptor (EGFR pathway. Previous studies from our laboratory have shown that increasing microenvironmental stiffness in culture can strongly enhance glioma cell behaviors relevant to tumor progression, including proliferation, yet it has remained unclear whether stiffness and EGFR regulate proliferation through common or independent signaling mechanisms. Here we test the hypothesis that microenvironmental stiffness regulates cell cycle progression and proliferation in GBM tumor cells by altering EGFR-dependent signaling. We began by performing an unbiased reverse phase protein array screen, which revealed that stiffness modulates expression and phosphorylation of a broad range of signals relevant to proliferation, including members of the EGFR pathway. We subsequently found that culturing human GBM tumor cells on progressively stiffer culture substrates both dramatically increases proliferation and facilitates passage through the G1/S checkpoint of the cell cycle, consistent with an EGFR-dependent process. Western Blots showed that increasing microenvironmental stiffness enhances the expression and phosphorylation of EGFR and its downstream effector Akt. Pharmacological loss-of-function studies revealed that the stiffness-sensitivity of proliferation is strongly blunted by inhibition of EGFR, Akt, or PI3 kinase. Finally, we observed that stiffness strongly regulates EGFR clustering, with phosphorylated EGFR condensing into vinculin-positive focal adhesions on stiff substrates and dispersing as microenvironmental stiffness falls to physiological levels. Our findings collectively support a model in which tissue stiffening promotes GBM proliferation by spatially and biochemically amplifying EGFR signaling.

  2. Preconditioning Human Mesenchymal Stem Cells with a Low Concentration of BMP2 Stimulates Proliferation and Osteogenic Differentiation In Vitro

    DEFF Research Database (Denmark)

    Lysdahl, Helle; Baatrup, Anette; Foldager, Casper Bindzus;

    2014-01-01

    treatment strategy in which human bone marrow-derived mesenchymal stem cells (hMSCs) are preconditioned with low concentrations of BMP2 for a short time in vitro. hMSCs in suspension were stimulated for 15 min with 10 and 20 ng/mL of BMP2. After the BMP2 was removed, the cells were seeded and cultured...... in osteogenesis was validated by findings of increased gene expression of SMAD1 and an increase in dual phosphorylation of ser 463 and ser 465 in the SMAD 1/5/8 pathway. We concluded that preconditioning hMSCs with BMP2 stimulates osteogenesis: proliferation with matrix secretion and matrix maturation of h......MSCs. This implies that preconditioning with BMP2 might be more effective at inducing proliferation and osteogenic differentiation of hMSCs than continuous stimulation. Preconditioning with BMP2 could benefit the clinical application of BMP2 since side effects from high-dose treatments could be avoided....

  3. H pylori stimulates proliferation of gastric cancer cells through activating mitogen-activated protein kinase cascade

    Institute of Scientific and Technical Information of China (English)

    Yong-Chang Chen; Ying Wang; Jing-Yan Li; Wen-Rong Xu; You-Li Zhang

    2006-01-01

    AIM: To explore the mechanism by which H pylori causes activation of gastric epithelial cells.METHODS: A VacA (+) and CagA (+) standard Hpyloriline NCTC 11637 and a human gastric adenocarcinoma derived gastric epithelial cell line BGC-823 were applied in the study. MTT assay and 3H-TdR incorporation test were used to detect the proliferation of BGC-823 cells and Western blotting was used to detect the activity and existence of related proteins.RESULTS: Incubation with Hpylori extract increased the proliferation of gastric epithelial cells, reflected by both live cell number and DNA synthesis rate. The activity of extracellular signal-regulated protein kinase (ERK) signal transduction cascade increased within 20 min after incubation with Hpylori extract and appeared to be a sustained event. MAPK/ERK kinase (MEK) inhibitor PD98059abolished the action of H pylori extract on both ERK activity and cell proliferation. Incubation with H pyloriextract increased c-Fos expression and SRE-dependentgene expression. H pylori extract caused phosphorylation of several proteins including a protein with molecular size of 97.4 kDa and tyrosine kinase inhibitor genistein inhibited the activation of ERK and the proliferation of cells caused by H pylori extract.CONCLUSION: Biologically active elements in H pylori extract cause proliferation of gastric epithelial cells through activating tyrosine kinase and ERK signal transduction cascade.

  4. Helium-neon laser irradiation stimulates cell proliferation through photostimulatory effects in mitochondria.

    Science.gov (United States)

    Hu, Wan-Ping; Wang, Jeh-Jeng; Yu, Chia-Li; Lan, Cheng-Che E; Chen, Gow-Shing; Yu, Hsin-Su

    2007-08-01

    Previous reports have shown that cellular functions could be influenced by visual light (400-700 nm). Recent evidence indicates that cellular proliferation could be triggered by the interaction of a helium-neon laser (He-Ne laser, 632.8 nm) with the mitochondrial photoacceptor-cytochrome c oxidase. Our previous studies demonstrated that He-Ne irradiation induced an increase in cell proliferation, but not migration, in the melanoma cell line A2058 cell. The aim of this study was to investigate the underlying mechanisms involved in photostimulatory effects induced by an He-Ne laser. Using the A2058 cell as a model for cell proliferation, the photobiologic effects induced by an He-Ne laser were studied. He-Ne irradiation immediately induced an increase in mitochondrial membrane potential (delta psi(mt)), ATP, and cAMP via enhanced cytochrome c oxidase activity and promoted phosphorylation of Jun N-terminal kinase (JNK)/activator protein-1 (AP-1) expressions. He-Ne irradiation-induced A2058 cell proliferation was significantly abrogated by the addition of delta psi(mt) and JNK inhibitors. Moreover, treatment with an He-Ne laser resulted in delayed effects on IL-8 and transforming growth factor-beta1 release from A2058 cells. These results suggest that He-Ne irradiation elicits photostimulatory effects in mitochondria processes, which involve JNK/AP-1 activation and enhanced growth factor release, and ultimately lead to A2058 cell proliferation.

  5. TIAR and TIA-1 mRNA binding proteins co-aggregate under conditions of rapid oxygen decline and extreme hypoxia, suppress HIF-1alpha pathway and inhibit proliferation and angiogenesis

    OpenAIRE

    Gottschald, Oana Raluca

    2010-01-01

    T-cell intracellular antigen (TIA)-1 and TIA-1 related protein (TIAR) are mRNA-binding proteins that aggregate within stress granules under specific stress conditions. In this study, we analyzed TIAR/TIA-1 aggregation under different hypoxic conditions, and studied the effects on hypoxia-inducible factor (HIF)-1alpha, as well as on proliferation and angiogenesis. TIAR/TIA-1 formed stress granules under acute and pronounced hypoxic conditions in A549 adenocarcinoma cells. In parallel, HIF-1alp...

  6. Platelet-rich plasma stimulated by pulse electric fields: Platelet activation, procoagulant markers, growth factor release and cell proliferation.

    Science.gov (United States)

    Frelinger, A L; Torres, A S; Caiafa, A; Morton, C A; Berny-Lang, M A; Gerrits, A J; Carmichael, S L; Neculaes, V B; Michelson, A D

    2016-01-01

    Therapeutic use of activated platelet-rich plasma (PRP) has been explored for wound healing, hemostasis and antimicrobial wound applications. Pulse electric field (PEF) stimulation may provide more consistent platelet activation and avoid complications associated with the addition of bovine thrombin, the current state of the art ex vivo activator of therapeutic PRP. The aim of this study was to compare the ability of PEF, bovine thrombin and thrombin receptor activating peptide (TRAP) to activate human PRP, release growth factors and induce cell proliferation in vitro. Human PRP was prepared in the Harvest SmartPreP2 System and treated with vehicle, PEF, bovine thrombin, TRAP or Triton X-100. Platelet activation and procoagulant markers and microparticle generation were measured by flow cytometry. Released growth factors were measured by ELISA. The releasates were tested for their ability to stimulate proliferation of human epithelial cells in culture. PEF produced more platelet-derived microparticles, P-selectin-positive particles and procoagulant annexin V-positive particles than bovine thrombin or TRAP. These differences were associated with higher levels of released epidermal growth factor after PEF than after bovine thrombin or TRAP but similar levels of platelet-derived, vascular-endothelial, and basic fibroblast growth factors, and platelet factor 4. Supernatant from PEF-treated platelets significantly increased cell proliferation compared to plasma. In conclusion, PEF treatment of fresh PRP results in generation of microparticles, exposure of prothrombotic platelet surfaces, differential release of growth factors compared to bovine thrombin and TRAP and significant cell proliferation. These results, together with PEF's inherent advantages, suggest that PEF may be a superior alternative to bovine thrombin activation of PRP for therapeutic applications.

  7. Stimulated human peripheral T cells produce high amounts of IL-35 protein in a proliferation-dependent manner.

    Science.gov (United States)

    Guttek, Karina; Reinhold, Dirk

    2013-10-01

    The p35 subunit of IL-12 and the Epstein-Barr virus-induced gene 3 (EBI3) have been shown to form a heterodimeric cytokine, named interleukin-35 (IL-35). Recently, mRNA expression of both IL-12p35 and EBI3 was clearly shown in stimulated human T effector cells. Here, we investigated the production of IL-35 protein in human anti-CD3/CD28-stimulated pan T cells as well as T cell subpopulations using a specific human IL-35 ELISA system. We measured high concentrations of IL-35 (up to 3 ng/ml) in cell culture supernatants of stimulated pan T cells as well as CD4(+), CD8(+) and CD4(+)CD25(-) T cell subpopulations at 72 h after stimulation. Very low amounts of IL-35, in the range of 100pg/ml, were detectable in supernatants of resting T cells. These observations could be confirmed using a dot-blot assay for IL-12p35 and EBI3. High concentrations of IL-35 could be also measured in cell culture supernatants of both, resting and stimulated CD4(+)CD25(+) T cells. In order to learn more about the regulation of IL-35 production, we studied the effect of dexamethasone, cyclosporine A and rapamycin on IL-35 production of anti-CD3/CD28-stimulated human pan T cells as well as CD4(+) and CD8(+) T cell subpopulations. All three drugs significantly suppressed IL-35 production of these cells in a proliferation-dependent manner. In summary, we could show that stimulated human peripheral blood T cells of healthy donors produce high amounts of IL-35 protein. However, the biological function of this cytokine remains to be elucidated.

  8. Mimicking hypoxia to treat anemia: HIF-stabilizer BAY 85-3934 (Molidustat stimulates erythropoietin production without hypertensive effects.

    Directory of Open Access Journals (Sweden)

    Ingo Flamme

    Full Text Available Oxygen sensing by hypoxia-inducible factor prolyl hydroxylases (HIF-PHs is the dominant regulatory mechanism of erythropoietin (EPO expression. In chronic kidney disease (CKD, impaired EPO expression causes anemia, which can be treated by supplementation with recombinant human EPO (rhEPO. However, treatment can result in rhEPO levels greatly exceeding the normal physiological range for endogenous EPO, and there is evidence that this contributes to hypertension in patients with CKD. Mimicking hypoxia by inhibiting HIF-PHs, thereby stabilizing HIF, is a novel treatment concept for restoring endogenous EPO production. HIF stabilization by oral administration of the HIF-PH inhibitor BAY 85-3934 (molidustat resulted in dose-dependent production of EPO in healthy Wistar rats and cynomolgus monkeys. In repeat oral dosing of BAY 85-3934, hemoglobin levels were increased compared with animals that received vehicle, while endogenous EPO remained within the normal physiological range. BAY 85-3934 therapy was also effective in the treatment of renal anemia in rats with impaired kidney function and, unlike treatment with rhEPO, resulted in normalization of hypertensive blood pressure in a rat model of CKD. Notably, unlike treatment with the antihypertensive enalapril, the blood pressure normalization was achieved without a compensatory activation of the renin-angiotensin system. Thus, BAY 85-3934 may provide an approach to the treatment of anemia in patients with CKD, without the increased risk of adverse cardiovascular effects seen for patients treated with rhEPO. Clinical studies are ongoing to investigate the effects of BAY 85-3934 therapy in patients with renal anemia.

  9. Growth Hormone Is Secreted by Normal Breast Epithelium upon Progesterone Stimulation and Increases Proliferation of Stem/Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Sara Lombardi

    2014-06-01

    Full Text Available Using in vitro and in vivo experimental systems and in situ analysis, we show that growth hormone (GH is secreted locally by normal human mammary epithelial cells upon progesterone stimulation. GH increases proliferation of a subset of cells that express growth hormone receptor (GHR and have functional properties of stem and early progenitor cells. In 72% of ductal carcinoma in situ lesions, an expansion of the cell population that expresses GHR was observed, suggesting that GH signaling may contribute to breast cancer development.

  10. Growth hormone is secreted by normal breast epithelium upon progesterone stimulation and increases proliferation of stem/progenitor cells.

    Science.gov (United States)

    Lombardi, Sara; Honeth, Gabriella; Ginestier, Christophe; Shinomiya, Ireneusz; Marlow, Rebecca; Buchupalli, Bharath; Gazinska, Patrycja; Brown, John; Catchpole, Steven; Liu, Suling; Barkan, Ariel; Wicha, Max; Purushotham, Anand; Burchell, Joy; Pinder, Sarah; Dontu, Gabriela

    2014-06-01

    Using in vitro and in vivo experimental systems and in situ analysis, we show that growth hormone (GH) is secreted locally by normal human mammary epithelial cells upon progesterone stimulation. GH increases proliferation of a subset of cells that express growth hormone receptor (GHR) and have functional properties of stem and early progenitor cells. In 72% of ductal carcinoma in situ lesions, an expansion of the cell population that expresses GHR was observed, suggesting that GH signaling may contribute to breast cancer development.

  11. Arginase inhibition reduces interleukin-1β-stimulated vascular smooth muscle cell proliferation by increasing nitric oxide synthase-dependent nitric oxide production

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jeongyeon; Ryoo, Sungwoo, E-mail: ryoosw08@kangwon.ac.kr

    2013-06-07

    Highlights: •Arginase inhibition suppressed proliferation of IL-1β-stimulated VSMCs in dose-dependent manner. •NO production from IL-1β-induced iNOS expression was augmented by arginase inhibition, reducing VSMC proliferation. •Incubation with cGMP analogues abolished IL-1β-dependent proliferation of VSMCs. -- Abstract: We investigated whether arginase inhibition suppressed interleukin (IL)-1β-stimulated proliferation in vascular smooth muscle cells (VSMCs) and the possible mechanisms involved. IL-1β stimulation increased VSMC proliferation, while the arginase inhibitor BEC and transfection of the antisense (AS) oligonucleotide against arginase I decreased VSMC proliferation and was associated with increased protein content of the cell cycle regulator p21Waf1/Cip1. IL-1β incubation induced inducible nitric oxide synthase (iNOS) mRNA expression and protein levels in a dose-dependent manner, but did not affect arginase I and II expression. Consistent with this data, IL-1β stimulation resulted in increase in NO production that was significantly augmented by arginase inhibition. The specific iNOS inhibitor 1400W abolished IL-1β-mediated NO production and further accentuated IL-1β-stimulated cell proliferation. Incubation with NO donors GSNO and DETA/NO in the presence of IL-1β abolished VSMCs proliferation and increased p21Waf1/Cip1 protein content. Furthermore, incubation with the cGMP analogue 8-Br-cGMP prevented IL-1β-induced VSMCs proliferation. In conclusion, arginase inhibition augmented iNOS-dependent NO production that resulted in suppression of IL-1β-induced VSMCs proliferation in a cGMP-dependent manner.

  12. Bone marrow mesenchymal stem cells stimulate proliferation and neuronal differentiation of retinal progenitor cells.

    Directory of Open Access Journals (Sweden)

    Jing Xia

    Full Text Available During retina development, retinal progenitor cell (RPC proliferation and differentiation are regulated by complex inter- and intracellular interactions. Bone marrow mesenchymal stem cells (BMSCs are reported to express a variety of cytokines and neurotrophic factors, which have powerful trophic and protective functions for neural tissue-derived cells. Here, we show that the expanded RPC cultures treated with BMSC-derived conditioned medium (CM which was substantially enriched for bFGF and CNTF, expressed clearly increased levels of nuclear receptor TLX, an essential regulator of neural stem cell (NSC self-renewal, as well as betacellulin (BTC, an EGF-like protein described as supporting NSC expansion. The BMSC CM- or bFGF-treated RPCs also displayed an obviously enhanced proliferation capability, while BMSC CM-derived bFGF knocked down by anti-bFGF, the effect of BMSC CM on enhancing RPC proliferation was partly reversed. Under differentiation conditions, treatment with BMSC CM or CNTF markedly favoured RPC differentiation towards retinal neurons, including Brn3a-positive retinal ganglion cells (RGCs and rhodopsin-positive photoreceptors, and clearly diminished retinal glial cell differentiation. These findings demonstrate that BMSCs supported RPC proliferation and neuronal differentiation which may be partly mediated by BMSC CM-derived bFGF and CNTF, reveal potential limitations of RPC culture systems, and suggest a means for optimizing RPC cell fate determination in vitro.

  13. Estrogen and progesterone stimulate Schwann cell proliferation in a sex- and age-dependent manner

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1999-01-01

    The effects of estrogen and progesterone on Schwann cell proliferation were studied in cultured segments of the rat sciatic nerve from adult male, female, and newborn rats, by measurement of [3H thymidine incorporation or bromo-deoxy-uridine- (BrdU)-labelling and immunocytochemistry. Estrogen (100...

  14. Increased Vitreous Shedding of Microparticles in Proliferative Diabetic Retinopathy Stimulates Endothelial Proliferation

    OpenAIRE

    Chahed, Sadri; Leroyer, Aurélie S.; Benzerroug, Mounir; Gaucher, David; Georgescu, Adriana; Picaud, Serge; Silvestre, Jean-Sébastien; Gaudric, Alain; Tedgui, Alain; Massin, Pascale; Boulanger, Chantal M.

    2009-01-01

    OBJECTIVE Diabetic retinopathy is associated with progressive retinal capillary activation and proliferation, leading to vision impairment and blindness. Microparticles are submicron membrane vesicles with biological activities, released following cell activation or apoptosis. We tested the hypothesis that proangiogenic microparticles accumulate in vitreous fluid in diabetic retinopathy. RESEARCH DESIGN AND METHODS Levels and cellular origin of vitreous and plasma microparticles from control ...

  15. Muscarinic receptors stimulate cell proliferation in the human urothelium-derived cell line UROtsa.

    Science.gov (United States)

    Arrighi, Nicola; Bodei, Serena; Lucente, Alessandra; Michel, Martin C; Zani, Danilo; Simeone, Claudio; Cunico, Sergio Cosciani; Spano, PierFranco; Sigala, Sandra

    2011-10-01

    The widespread non-neuronal synthesis of acetylcholine (ACh) has changed the paradigm of ACh acting solely as a neurotransmitter. Indeed, the presence of ACh in many types of proliferating cells suggests a role for this neurotransmitter in the control of cell division. The parasympathetic system is a major pathway regulating micturition, but ACh-mediated control plays a more complex role than previously described, acting not only in the detrusor muscle, but also influencing detrusor function through the activity of urothelial muscarinic receptors. Here we investigated the role of muscarinic receptors in mediating cell proliferation in the human UROtsa cell line, which is a widely used experimental model to study urothelium physiology and pathophysiology. Our results demonstrate that UROtsa cells express the machinery for ACh synthesis and that muscarinic receptors, with the rank order of M3>M2>M5>M1=M4, are present and functionally linked to their known second messengers. Indeed, the cholinergic receptor agonist carbachol (CCh) (1-100 μM) concentration-dependently raised IP(3) levels, reaching 66±5% over basal. The forskolin-mediated adenylyl cyclase activation was reduced by CCh exposure (forskolin: 1.4±0.14 pmol/ml; forskolin+100 μM CCh: 0.84±0.12 pmol/ml). CCh (1-100 μM) concentration-dependently increased UROtsa cell proliferation and this effect was inhibited by the non-selective antagonist atropine and the M(3)-selective antagonists darifenacin and J104129. Finally, CCh-induced cell proliferation was blocked by selective PI-3 kinase and ERK activation inhibitors, strongly suggesting that these intracellular pathways mediate, at least in part, the muscarinic receptor-mediated cell proliferation.

  16. Polysaccharides of St. John's Wort Herb Stimulate NHDF Proliferation and NEHK Differentiation via Influence on Extracellular Structures and Signal Pathways.

    Science.gov (United States)

    Abakuks, S; Deters, A M

    2012-01-01

    St. John's Wort herb extracts often contain undesirable or volitional polysaccharides. As polysaccharides exhibit structure-dependent biological functions in the present study water-soluble polysaccharides were extracted from herb material, fractionated by anion exchange chromatography into four main polysaccharide fractions (denominated as Hp1, Hp2, Hp3 and Hp4) and characterized by HPAEC-PAD, CE, IR and GC-MS. Biological activity on human skin keratinocytes and fibroblasts was assessed by investigation of their effect on proliferation, metabolism, cytotoxicity, apoptosis and differentiation. The underlying mechanisms were investigated in gene expression studies. Polysaccharide fraction Hp1 was mainly composed of β-D-glucose. Hp2, Hp3 and Hp4 contained pectic structures and arabinogalactan proteins varying in composition and quantity. Polysaccharides of Hp1 induced the keratinocyte differentiation by inhibiting the gene expression of the epidermal growth factor and insulin receptor. While the collagen secretion of fibroblasts was stimulated by each polysaccharide fraction only Hp1 stimulated the synthesis. The fibroblast proliferation was reduced by Hp1 and increased by Hp4. This effect was related to the influence on genes that referred to oxidative stress, metabolism, transcription processes and extracellular proteins. In conclusion polysaccharides have been shown as biologically active ingredients of aqueous St. John's Wort extracts with a relation between their structural characteristics and function.

  17. Adenosine Stimulate Proliferation and Migration in Triple Negative Breast Cancer Cells

    Science.gov (United States)

    Fernandez-Gallardo, Miriam; González-Ramírez, Ricardo; Sandoval, Alejandro; Monjaraz, Eduardo

    2016-01-01

    Emerging evidence suggests that the adenosine (Ado) receptors may play crucial roles in tumor progression. Here, we show that Ado increases proliferation and migration in a triple negative breast cancer model, the MDA-MB 231 cell line. The use of specific agonists and antagonists evidenced that these effects depend on the activation of the A2B receptor, which then triggers an intracellular response mediated by the adenylate cyclase/PKA/cAMP signaling pathway. Ado also increases the expression of NaV1.5 channels, a potential biomarker in breast cancer. Together, these data suggest important roles of the A2B receptors and NaV1.5 channels in the Ado-induced increase in proliferation and migration of the MDA-MB 231 cells. PMID:27911956

  18. Diabetic HDL is dysfunctional in stimulating endothelial cell migration and proliferation due to down regulation of SR-BI expression.

    Science.gov (United States)

    Pan, Bing; Ma, Yijing; Ren, Hui; He, Yubin; Wang, Yongyu; Lv, Xiaofeng; Liu, Donghui; Ji, Liang; Yu, Baoqi; Wang, Yuhui; Chen, Y Eugene; Pennathur, Subramaniam; Smith, Jonathan D; Liu, George; Zheng, Lemin

    2012-01-01

    Diabetic HDL had diminished capacity to stimulate endothelial cell (EC) proliferation, migration, and adhesion to extracellular matrix. The mechanism of such dysfunction is poorly understood and we therefore sought to determine the mechanistic features of diabetic HDL dysfunction. We found that the dysfunction of diabetic HDL on human umbilical vein endothelial cells (HUVECs) was associated with the down regulation of the HDL receptor protein, SR-BI. Akt-phosphorylation in HUVECs was induced in a biphasic manner by normal HDL. While diabetic HDL induced Akt phosphorylation normally after 20 minutes, the phosphorylation observed 24 hours after diabetic HDL treatment was reduced. To determine the role of SR-BI down regulation on diminished EC responses of diabetic HDL, Mouse aortic endothelial cells (MAECs) were isolated from wild type and SR-BI (-/-) mice, and treated with normal and diabetic HDL. The proliferative and migratory effects of normal HDL on wild type MAECs were greatly diminished in SR-BI (-/-) cells. In contrast, response to diabetic HDL was impaired in both types suggesting diminished effectiveness of diabetic HDL on EC proliferation and migration might be due to the down regulation of SR-BI. Additionally, SR-BI down regulation diminishes diabetic HDL's capacity to activate Akt chronically. Diabetic HDL was dysfunctional in promoting EC proliferation, migration, and adhesion to matrix which was associated with the down-regulation of SR-BI. Additionally, SR-BI down regulation diminishes diabetic HDL's capacity to activate Akt chronically.

  19. Tamarind Seed Xyloglucans Promote Proliferation and Migration of Human Skin Cells through Internalization via Stimulation of Proproliferative Signal Transduction Pathways.

    Science.gov (United States)

    Nie, W; Deters, A M

    2013-01-01

    Xyloglucans (XGs) of Tamarindus indica L. Fabaceae are used as drug vehicles or as ingredients of cosmetics. Two xyloglucans were extracted from T. indica seed with cold water (TSw) and copper complex precipitation (TSc). Both were analyzed in regard to composition and influence on cell viability, proliferation, cell cycle progression, migration, MAPK phosphorylation, and gene expression of human skin keratinocytes (NHEK and HaCaT) and fibroblasts (NHDF) in vitro. TSw and TSc differed in molecular weight, rhamnose content, and ratios of xylose, arabinose, galactose, and glucose. Both XGs improved keratinocytes and fibroblast proliferation, promoted the cell cycle, and stimulated migration and intracellular enzyme activity of NHDF after endosomal uptake. Only TSw significantly enhanced HaCaT migration and extracellular enzyme activity of NHDF and HaCaT. TSw and TSc predominantly enhanced the phosphorylation of molecules that referred to Erk signaling in NHEK. In NHDF parts of the integrin signaling and SAPK/JNK pathway were affected. Independent of cell type TSw marginally regulated the expression of genes, which referred to membrane proteins, cytoskeleton, cytokine signaling, and ECM as well as to processes of metabolism and transcription. Results show that T. indica xyloglucans promote skin regeneration by a direct influence on cell proliferation and migration.

  20. Tamarind Seed Xyloglucans Promote Proliferation and Migration of Human Skin Cells through Internalization via Stimulation of Proproliferative Signal Transduction Pathways

    Directory of Open Access Journals (Sweden)

    W. Nie

    2013-01-01

    Full Text Available Xyloglucans (XGs of Tamarindus indica L. Fabaceae are used as drug vehicles or as ingredients of cosmetics. Two xyloglucans were extracted from T. indica seed with cold water (TSw and copper complex precipitation (TSc. Both were analyzed in regard to composition and influence on cell viability, proliferation, cell cycle progression, migration, MAPK phosphorylation, and gene expression of human skin keratinocytes (NHEK and HaCaT and fibroblasts (NHDF in vitro. TSw and TSc differed in molecular weight, rhamnose content, and ratios of xylose, arabinose, galactose, and glucose. Both XGs improved keratinocytes and fibroblast proliferation, promoted the cell cycle, and stimulated migration and intracellular enzyme activity of NHDF after endosomal uptake. Only TSw significantly enhanced HaCaT migration and extracellular enzyme activity of NHDF and HaCaT. TSw and TSc predominantly enhanced the phosphorylation of molecules that referred to Erk signaling in NHEK. In NHDF parts of the integrin signaling and SAPK/JNK pathway were affected. Independent of cell type TSw marginally regulated the expression of genes, which referred to membrane proteins, cytoskeleton, cytokine signaling, and ECM as well as to processes of metabolism and transcription. Results show that T. indica xyloglucans promote skin regeneration by a direct influence on cell proliferation and migration.

  1. Folic Acid Supplementation Stimulates Notch Signaling and Cell Proliferation in Embryonic Neural Stem Cells

    OpenAIRE

    Liu,Huan; Huang, Guo-Wei; Zhang, Xu-Mei; Ren, Da-lin; X. Wilson, John

    2010-01-01

    The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14–16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation ...

  2. Constant Applied Force Stimulates Osteoblast Proliferation Via Matrix-Integrin-Signaling Pathways

    Science.gov (United States)

    Vercoutere, W.; Parra, M.; Roden, C.; DaCosta, M.; Wing, A.; Damsky, C.; Holton, E.; Searby, N.; Globus, R.; Almeida, E. A. C.

    2003-01-01

    Reduced weight-bearing caused by immobilization, bed-rest or microgravity leads to atrophy in mechanosensitive tissue such as muscle and bone. We hypothesize that bone tissue requires earth s gravity (1-g) for the maintenance of extracellular matrix, integrin, and kinase-mediated cell growth and survival pathways. We investigate the role of matrix-integrin signaling in bone cells using cell culture centrifugation to provide different levels of hypergravity mechanostimulation. The 10-50-g range we use also mimics physiological intermedullary pressure (1.2 - 5 kPa). 24 hours at 50-g increased primary rat osteoblast proliferation on collagen Type I and fibronectin, but not laminin or uncoated plastic. BrdU incorporation in primary osteoblasts over 24 h showed hypergravity increased the number of cells actively synthesizing DNA from about 60% at 1-g to over 90% at 25-g. Primary rat fibroblasts grown at 50-g (24 h) showed no proliferation increase, suggesting this is a tissue-specific phenomenon. These results suggest that the betal and alpha4 integrins may be involved. To further test this, we used osteocytic-like MLO-Y4 cells that showed increased proliferation at 1-g with stable expression of a betal integrin cytoplasmic tail and transmembrane domain construct. At 50-g, MLO-Y4/betal cells showed greater MAPK activation than MLO-Y4 vector controls, suggesting that betal integrin is involved in transducing mitogenic signals in response to hypergravity. Preliminary results also show that interfering with the alpha4 integrin in primary osteoblasts grown on fibronectin blocked the proliferation response. These results indicate that cells from mechanosensitive bone tissue can respond to gravity-generated forces, and this response involves specific matrix and integrin-dependent signaling pathways.

  3. Chitosan Degradation Products Promote Nerve Regeneration by Stimulating Schwann Cell Proliferation via miR-27a/FOXO1 Axis.

    Science.gov (United States)

    Wang, Yongjun; Zhao, Yahong; Sun, Cheng; Hu, Wen; Zhao, Jing; Li, Guicai; Zhang, Luzhong; Liu, Mei; Liu, Yan; Ding, Fei; Yang, Yumin; Gu, Xiaosong

    2016-01-01

    Natural polysaccharides are biomaterials widely used for constructing scaffolds in tissue engineering. While natural polysaccharides have been shown to robustly promote tissue regeneration, the underlying molecular mechanism remains largely unknown. Here, we show that chitooligosaccharides (COS), the intermediate products of chitosan degradation, stimulate peripheral nerve regeneration in rats. Our experiment also shows that COS stimulate the proliferation of Schwann cells (SCs) during nerve regeneration. By analyzing the transcriptome and gene regulatory network, we identified the miR-27a/FOXO1 axis as the main signaling pathway for mediating the proliferative effects of COS on SCs. COS increase the expression level of miR-27a and cause a reduction of FOXO1, which subsequently accelerates the cell cycle and stimulates SC proliferation to stimulate nerve regeneration. These findings define a basic pathway for oligosaccharides-mediated cell proliferation and reveal a novel aspect of polysaccharide biomaterials in tissue engineering.

  4. ENHANCEMENT OF NIH3T3 CELL PROLIFERATION BY EXPRESSING MACROPHAGE COLONY STIMULATING FACTOR IN NUCLEI

    Institute of Scientific and Technical Information of China (English)

    曹震宇; 吴克复; 李戈; 林永敏; 张斌; 郑国光

    2003-01-01

    Objective: To explore the effects of nuclear M-CSF on the process of tumorigenesis. Methods: Functional part of M-CSF cDNA was inserted into an eukaryotic expression plasmid pCMV/myc/nuc, which can add three NLS to the C-terminal of the expressed protein and direct the protein into the cell nuclei. The constructed plasmid was transferred into NIH3T3 cells and the cell clones were selected by G-418 selection. Cell clones stable expressing target protein were identified by RT-PCR, ABC immunohistochemistry assay and Western blot. Cell growth kinetics analyses through growth curves, cell doubling time, MTT test and anti-sense oligodeoxynucleotide (ASODN) inhibiting cell growth test were performed to identify cells proliferation potential. Results: The transfected cells showed elevated proliferation potential over the control cells. Conclusion: Abnormal appearance of M-CSF in nucleus could enhance cell proliferation, which suggests that cytokine isoforms within cell nucleus might play transcription factor-like role.

  5. The TGFβ pathway stimulates ovarian cancer cell proliferation by increasing IGF1R levels.

    Science.gov (United States)

    Alsina-Sanchis, Elisenda; Figueras, Agnès; Lahiguera, Álvaro; Vidal, August; Casanovas, Oriol; Graupera, Mariona; Villanueva, Alberto; Viñals, Francesc

    2016-10-15

    In a search for new therapeutic targets for treating epithelial ovarian cancer, we analyzed the Transforming Growth Factor Beta (TGFβ) signaling pathway in these tumors. Using a TMA with patient samples we found high Smad2 phosphorylation in ovarian cancer tumoral cells, independently of tumor subtype (high-grade serous or endometrioid). To evaluate the impact of TGFβ receptor inhibition on tumoral growth, we used different models of human ovarian cancer orthotopically grown in nude mice (OVAs). Treatment with a TGFβRI&II dual inhibitor, LY2109761, caused a significant reduction in tumor size in all these models, affecting cell proliferation rate. We identified Insulin Growth Factor (IGF)1 receptor as the signal positively regulated by TGFβ implicated in ovarian tumor cell proliferation. Inhibition of IGF1R activity by treatment with a blocker antibody (IMC-A12) or with a tyrosine kinase inhibitor (linsitinib) inhibited ovarian tumoral growth in vivo. When IGF1R levels were decreased by shRNA treatment, LY2109761 lost its capacity to block tumoral ovarian cell proliferation. At the molecular level TGFβ induced mRNA IGF1R levels. Overall, our results suggest an important role for the TGFβ signaling pathway in ovarian tumor cell growth through the control of IGF1R signaling pathway. Moreover, it identifies anti-TGFβ inhibitors as being of potential use in new therapies for ovarian cancer patients as an alternative to IGF1R inhibition.

  6. Differential regulation of LncRNA-SARCC suppresses VHL-mutant RCC cell proliferation yet promotes VHL-normal RCC cell proliferation via modulating androgen receptor/HIF-2α/C-MYC axis under hypoxia.

    Science.gov (United States)

    Zhai, W; Sun, Y; Jiang, M; Wang, M; Gasiewicz, T A; Zheng, J; Chang, C

    2016-09-15

    It is well established that hypoxia contributes to tumor progression in a hypoxia inducible factor-2α (HIF-2α)-dependent manner in renal cell carcinoma (RCC), yet the role of long noncoding RNAs (LncRNAs) involved in hypoxia-mediated RCC progression remains unclear. Here we demonstrate that LncRNA-SARCC (Suppressing Androgen Receptor in Renal Cell Carcinoma) is differentially regulated by hypoxia in a von Hippel-Lindau (VHL)-dependent manner both in RCC cell culture and clinical specimens. LncRNA-SARCC can suppress hypoxic cell cycle progression in the VHL-mutant RCC cells while derepress it in the VHL-restored RCC cells. Mechanism dissection reveals that LncRNA-SARCC can post-transcriptionally regulate androgen receptor (AR) by physically binding and destablizing AR protein to suppress AR/HIF-2α/C-MYC signals. In return, HIF-2α can transcriptionally regulate the LncRNA-SARCC expression via binding to hypoxia-responsive elements on the promoter of LncRNA-SARCC. The negative feedback modulation between LncRNA-SARCC/AR complex and HIF-2α signaling may then lead to differentially modulated RCC progression in a VHL-dependent manner. Together, these results may provide us a new therapeutic approach via targeting this newly identified signal from LncRNA-SARCC to AR-mediated HIF-2α/C-MYC signals against RCC progression.

  7. Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    Yamauchi Mika

    2007-11-01

    Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

  8. Altered expression of cell proliferation-related and interferon-stimulated genes in colon cancer cells resistant to SN38.

    Science.gov (United States)

    Gongora, Céline; Candeil, Laurent; Vezzio, Nadia; Copois, Virginie; Denis, Vincent; Breil, Corinne; Molina, Franck; Fraslon, Caroline; Conseiller, Emmanuel; Pau, Bernard; Martineau, Pierre; Del Rio, Maguy

    2008-06-01

    Irinotecan is a topoisomerase I inhibitor widely used as an anticancer agent in the treatment of metastatic colon cancer. However, its efficacy is often limited by the development of resistance. We have isolated a colon carcinoma cell line, HCT116-SN6, which displays a 6-fold higher resistance to SN38, the active metabolite of irinotecan. In this paper, we studied the molecular mechanisms that cause resistance to SN38 in the HCT116-SN6 cell line. First, we analyzed proliferation, cell cycle distribution, apoptosis, topoisomerase I expression and activity in SN38-resistant (HCT116-SN6) and sensitive (HCT116-s cells). We showed that the SN38-induced apoptosis and the SN38-activated cell cycle checkpoints leading to G(2)/M cell cycle arrest were similar in both cell lines. Topoisomerase I expression and catalytic activity were also unchanged. Then, we compared mRNA expression profiles in the two cell lines using the Affymetrix Human Genome GeneChip arrays U133A and B. Microarray analysis showed that among the genes, which were differentially expressed in HCT116-s and HCT116-SN6 cells, 27% were related to cell proliferation suggesting that proliferation might be the main target in the development of resistance to SN38. This result correlates with the phenotypic observation of a reduced growth rate in HCT116-SN6 resistant cells. Furthermore, 29% of the overexpressed genes were Interferon Stimulated Genes and we demonstrate that their overexpression is, at least partially, due to endogenous activation of the p38 MAP kinase pathway in SN38 resistant cells. In conclusion, a slower cell proliferation rate may be a major cause of acquired resistance to SN38 via a reduction of cell cycle progression through the S phase which is mandatory for the cytotoxic action of SN38. This lower growth rate could be due to the endogenous activation of p38.

  9. Sonic hedgehog stimulates glycolysis and proliferation of breast cancer cells: Modulation of PFKFB3 activation

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Xin; Lyu, Pengwei; Gu, Yuanting; Li, Lin; Li, Jingruo; Wang, Yan; Zhang, Linfeng [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Fu, Chao [Department of Ultrasonography, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China); Cao, Zhang, E-mail: zzzhangcao@126.com [Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan (China)

    2015-08-28

    Sonic hesgehog (Shh) signaling has been reported to play an essential role in cancer progression. The mechanism of Shh involved in breast cancer carcinogenesis remains unclear. The present study sought to explore whether Shh signaling could regulate the glycolytic metabolism in breast cancers. Overexpression of the smoothed (Smo) and Gli-1 was found in human primary breast cancers. The expressions of Shh and Gli-1 correlated significantly with tumor size and tumor stage. In vitro, human recombinant Shh (rShh) triggered Smo and Gli-1 expression, promoted glucose utilization and lactate production, and accelerated cell proliferation in MCF-7 and MDA-MB-231 cells. Notably, rShh did not alter 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) expression but augmented PFKFB3 phosphorylation on ser{sup 461}, along with elevated fructose-2,6-bisphosphate (F2,6BP) generation by MCF-7 and MDA-MB-231 cells. This effect could be dampened by Smo siRNA but not by Gli-1 siRNA. In addition, our data showed the upregulated expressions of MAPK by rShh and elevatory PFKFB3 phosphorylation by p38/MAPK activated kinase (MK2). In conclusion, our study characterized a novel role of Shh in promoting glycolysis and proliferation of breast cancer cells via PFKFB3 phosphorylation, which was mediated by Smo and p38/MK2. - Highlights: • Overexpression of Smo and Gli-1 was found in human primary breast cancers. • Shh promoted glucose utilization, lactate production, and cell proliferation. • Shh did not alter PFKFB3 expression but augmented PFKFB3 phosphorylation on ser461. • Shh acts on PFKFB3 phosphorylation via Smo and p38 MAPK/MK2.

  10. Influence of inositol hexaphosphate on the expression of selected proliferation markers in IL-1β-stimulated intestinal epithelial cells.

    Science.gov (United States)

    Kapral, Małgorzata; Sośnicki, Stanisław; Wawszczyk, Joanna; Węglarz, Ludmiła

    2014-01-01

    The aim of the present study was to examine the influence of IP6, a naturally occurring phytochem- ical, on the expression of genes coding for proliferation markers, i.e., cyclin D1 (CCND1) and histone H3 in IL-1β-stimulated intestinal cancer cell line Caco-2. Quantification of genes expression was carried out using real time RT-QPCR technique in Caco-2 cells after treatment with IL-1β, 1 and 2.5 mM of IP6 for 3, 6 and 12 h. In separate cultures, cells were incubated with IL-1β for the indicated times. The untreated Caco-2 cells were used as the control. In a time course experiment, stimulation of cells with IL-1β only resulted in an overex- pression of both CCND1 and histone H3 mRNAs as compared with control. IP6 had no influence on IL-1β-stimulated CCND1 expression for 3 and 6 h. After 12 h, statistically significant decrease in CCND1 mRNA was observed in cells exposed to IL-1β and IP6 (1 and 2.5 mM) in relation to cells treated with IL-1β only. The levels of H3 mRNA in IL-1β-stimulated cells and cells treated with IL-1β and IP6 revealed no statistically significant differences after 3 h. IP6 at 1 and 2.5 mM enhanced IL1β-stimulated transcription of H3 gene after 6 h. Subsequently (12 h), the combination of IP6 and IL-1β decreased H3 mRNA level compared to IL1β-treated cells. In conclusion, pro-inflammatory cytokine IL-1β up-regulates CCND1 and histone H3 mRNAs expression in Caco-2 cells. These results suggest that the ability of IP6 to inhibit colon cancer cells proliferation may be mediated through downregulation of genes encoding cyclin D1 and histone H3 at the mRNA level.

  11. Upregulation of Steroidogenic Acute Regulatory Protein by Hypoxia Stimulates Aldosterone Synthesis in Pulmonary Artery Endothelial Cells to Promote Pulmonary Vascular Fibrosis

    Science.gov (United States)

    Maron, Bradley A.; Oldham, William M.; Chan, Stephen Y.; Vargas, Sara O.; Arons, Elena; Zhang, Ying-Yi; Loscalzo, Joseph; Leopold, Jane A.

    2014-01-01

    Background The molecular mechanism(s) regulating hypoxia-induced vascular fibrosis are unresolved. Hyperaldosteronism correlates positively with vascular remodeling in pulmonary arterial hypertension (PAH), suggesting that aldosterone may contribute to the pulmonary vasculopathy of hypoxia. The hypoxia-sensitive transcription factors c-Fos/c-Jun regulate steroidogenic acute regulatory protein (StAR), which facilitates the rate-limiting step of aldosterone steroidogenesis. We hypothesized that c-Fos/c-Jun upregulation by hypoxia activates StAR-dependent aldosterone synthesis in human pulmonary artery endothelial cells (HPAECs) to promote vascular fibrosis in PAH. Methods and Results Patients with PAH, rats with Sugen/hypoxia-PAH, and mice exposed to chronic hypoxia expressed increased StAR in remodeled pulmonary arterioles, providing a basis for investigating hypoxia-StAR signaling in HPAECs. Hypoxia (2.0% FiO2) increased aldosterone levels selectively in HPAECs, which was confirmed by liquid chromatography-mass spectrometry. Increased aldosterone by hypoxia resulted from enhanced c-Fos/c-Jun binding to the proximal activator protein (AP-1) site of the StAR promoter in HPAECs, which increased StAR expression and activity. In HPAECs transfected with StAR-siRNA or treated with the AP-1 inhibitor, SR-11302, hypoxia failed to increase aldosterone, confirming that aldosterone biosynthesis required StAR activation by c-Fos/c-Jun. The functional consequences of aldosterone were confirmed by pharmacological inhibition of the mineralocorticoid receptor with spironolactone or eplerenone, which attenuated hypoxia-induced upregulation of the fibrogenic protein connective tissue growth factor and collagen III in vitro, and decreased pulmonary vascular fibrosis to improve pulmonary hypertension in Conclusions Our findings identify autonomous aldosterone synthesis in HPAECs due to hypoxia-mediated upregulation of StAR as a novel molecular mechanism that promotes pulmonary vascular

  12. KGF-transfected cells can stimulate growth and proliferation of human cultured keratinocytes in vitro

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Objective: To establish two stably KGF-transfected, immortalized cell lines. Methods: HaCaT-keratinocytes and KMST-6-fibroblasts were transfected by liposome mediated gene transfer. Transfection effectivity, gene integration and configuration of the transgenic protein were investigated by ELISA, DANN-PCR and β-Gal-staining. Results: Most effective GF producing clones were tested by a colorimetric XTT-test. Conclusion: This is a significant acceleration of cell proliferation and mitosis of human keratinocytes in an Air Liquid Interface (ALI) test system.

  13. Elimination of the geomagnetic field stimulates the proliferation of mouse neural progenitor and stem cells

    Directory of Open Access Journals (Sweden)

    Jing-Peng Fu

    2016-08-01

    Full Text Available Abstract Living organisms are exposed to the geomagnetic field (GMF throughout their lifespan. Elimination of the GMF, resulting in a hypogeomagnetic field (HMF, leads to central nervous system dysfunction and abnormal development in animals. However, the cellular mechanisms underlying these effects have not been identified so far. Here, we show that exposure to an HMF (<200 nT, produced by a magnetic field shielding chamber, promotes the proliferation of neural progenitor/stem cells (NPCs/NSCs from C57BL/6 mice. Following seven-day HMF-exposure, the primary neurospheres (NSs were significantly larger in size, and twice more NPCs/NSCs were harvested from neonatal NSs, when compared to the GMF controls. The self-renewal capacity and multipotency of the NSs were maintained, as HMF-exposed NSs were positive for NSC markers (Nestin and Sox2, and could differentiate into neurons and astrocyte/glial cells and be passaged continuously. In addition, adult mice exposed to the HMF for one month were observed to have a greater number of proliferative cells in the subventricular zone. These findings indicate that continuous HMF-exposure increases the proliferation of NPCs/NSCs, in vitro and in vivo. HMF-disturbed NPCs/NSCs production probably affects brain development and function, which provides a novel clue for elucidating the cellular mechanisms of the bio-HMF response.

  14. Circulating progenitor cells during exercise, muscle electro-stimulation and intermittent hypobaric hypoxia in patients with traumatic brain injury: a pilot study.

    Science.gov (United States)

    Corral, Luisa; Conde, Laura; Guillamó, Elisabet; Blasi, Juan; Juncadella, Montserrat; Javierre, Casimiro; Viscor, Ginés; Ventura, Josep L

    2014-01-01

    Circulating progenitor cells (CPC) treatments may have great potential for the recovery of neurons and brain function. To increase and maintain CPC with a program of exercise, muscle electro-stimulation (ME) and/or intermittent-hypobaric-hypoxia (IHH), and also to study the possible improvement in physical or psychological functioning of participants with Traumatic Brain Injury (TBI). Twenty-one participants. Four groups: exercise and ME group (EEG), cycling group (CyG), IHH and ME group (HEG) and control group (CG). Psychological and physical stress tests were carried out. CPC were measured in blood several times during the protocol. Psychological tests did not change. In the physical stress tests the VO2 uptake increased in the EEG and the CyG, and the maximal tolerated workload increased in the HEG. CPC levels increased in the last three weeks in EEG, but not in CyG, CG and HEG. CPC levels increased in the last three weeks of the EEG program, but not in the other groups and we did not detect performed psychological test changes in any group. The detected aerobic capacity or workload improvement must be beneficial for the patients who have suffered TBI, but exercise type and the mechanisms involved are not clear.

  15. ADAM12-S stimulates bone growth in transgenic mice by modulating chondrocyte proliferation and maturation

    DEFF Research Database (Denmark)

    Kveiborg, Marie; Albrechtsen, Reidar; Rudkjaer, Lise

    2006-01-01

    ADAM12-S transgenic mice exhibit a pronounced increase in the length of bones, such as femur, tibia, and vertebrae. The effect of ADAM12-S on longitudinal bone growth involves the modulation of chondrocyte proliferation and maturation, likely through proteolytic activities and altered cell......-extracellular matrix interactions in the growth plate. INTRODUCTION: The disintegrin and metalloprotease ADAM12 is expressed in both osteoblasts and osteoclasts, suggesting a regulatory role of ADAM12 in bone. However, thus far, no in vivo function of ADAM12 in the skeleton has been reported. MATERIALS AND METHODS......-extracellular matrix interactions. RESULTS: ADAM12-S transgenic mice exhibit increased longitudinal bone growth. The increased bone length is progressive and age dependent, with a maximum increase of 17% seen in the femur from 6-month-old transgenic mice. The effect is gene dose dependent, being more pronounced...

  16. Cyclic mechanical deformation stimulates human lung fibroblast proliferation and autocrine growth factor activity.

    Science.gov (United States)

    Bishop, J E; Mitchell, J J; Absher, P M; Baldor, L; Geller, H A; Woodcock-Mitchell, J; Hamblin, M J; Vacek, P; Low, R B

    1993-08-01

    Cellular hypertrophy and hyperplasia and increased extracellular matrix deposition are features of tissue hypertrophy resulting from increased work load. It is known, for example, that mechanical forces play a critical role in lung development, cardiovascular remodeling following pressure overload, and skeletal muscle growth. The mechanisms involved in these processes, however, remain unclear. Here we examined the effect of mechanical deformation on fibroblast function in vitro. IMR-90 human fetal lung fibroblasts grown on collagen-coated silastic membranes were subjected to cyclical mechanical deformation (10% increase in culture surface area; 1 Hz) for up to 5 days. Cell number was increased by 39% after 2 days of deformation (1.43 +/- .01 x 10(5) cells/membrane compared with control, 1.03 +/- 0.02 x 10(5) cells; mean +/- SEM; P < 0.02) increasing to 163% above control by 4 days (2.16 +/- 0.16 x 10(5) cells compared with 0.82 +/- 0.03 x 10(5) cells; P < 0.001). The medium from mechanically deformed cells was mitogenic for IMR-90 cells, with maximal activity in the medium from cells mechanically deformed for 2 days (stimulating cell replication by 35% compared with media control; P < 0.002). These data suggest that mechanical deformation stimulates human lung fibroblast replication and that this effect is mediated by the release of autocrine growth factors.

  17. Stimulating Neoblast-Like Cell Proliferation in Juvenile Fasciola hepatica Supports Growth and Progression towards the Adult Phenotype In Vitro

    Science.gov (United States)

    Rathinasamy, Vignesh; Toet, Hayley; McCammick, Erin; O’Connor, Anna; Marks, Nikki J.; Mousley, Angela; Brennan, Gerard P.; Halton, David W.; Spithill, Terry W.; Maule, Aaron G.

    2016-01-01

    Fascioliasis (or fasciolosis) is a socioeconomically important parasitic disease caused by liver flukes of the genus Fasciola. Flukicide resistance has exposed the need for new drugs and/or a vaccine for liver fluke control. A rapidly improving ‘molecular toolbox’ for liver fluke encompasses quality genomic/transcriptomic datasets and an RNA interference platform that facilitates functional genomics approaches to drug/vaccine target validation. The exploitation of these resources is undermined by the absence of effective culture/maintenance systems that would support in vitro studies on juvenile fluke development/biology. Here we report markedly improved in vitro maintenance methods for Fasciola hepatica that achieved 65% survival of juvenile fluke after 6 months in standard cell culture medium supplemented with 50% chicken serum. We discovered that this long-term maintenance was dependent upon fluke growth, which was supported by increased proliferation of cells resembling the “neoblast” stem cells described in other flatworms. Growth led to dramatic morphological changes in juveniles, including the development of the digestive tract, reproductive organs and the tegument, towards more adult-like forms. The inhibition of DNA synthesis prevented neoblast-like cell proliferation and inhibited growth/development. Supporting our assertion that we have triggered the development of juveniles towards adult-like fluke, mass spectrometric analyses showed that growing fluke have an excretory/secretory protein profile that is distinct from that of newly-excysted juveniles and more closely resembles that of ex vivo immature and adult fluke. Further, in vitro maintained fluke displayed a transition in their movement from the probing behaviour associated with migrating stage worms to a slower wave-like motility seen in adults. Our ability to stimulate neoblast-like cell proliferation and growth in F. hepatica underpins the first simple platform for their long-term in

  18. A novel thrombopoietin-stem-cell factor fusion protein possesses enhanced potential in stimulating megakaryocyte proliferation and differentiation.

    Science.gov (United States)

    Zang, Yuhui; Zhang, Yumin; Peng, Wei; Chen, Bin; Zhu, Jie; Zhang, Chi; Ouyang, Jian; Qin, Junchuan

    2007-11-01

    TPO (thrombopoietin) and SCF (stem-cell factor) are functionally related cytokines with overlapping but distinct haematopoietic effects. In the present study, a novel TPO-SCF fusion protein that combined the complementary biological effects of TPO and SCF into a single molecule was expressed in, and purified from, Sf9 [Spodoptera frugiperda (fall armyworm)] insect cells. The specific activity of rhTPO (recombinant human TPO)-SCF in megakaryoblastic Mo7e cell proliferation assays was 2.90+/-0.35 x 10(7) units/micromol, approx. 1.7 times as high as that of rhTPO. The specific activity of rhTPO-SCF in TF-1 cells proliferation assays was 7.10+/-0.95 x 10(6) units/micromol, approx. 1.2 times as high as that of rhSCF (recombinant human SCF). In a megakaryocyte-colony-forming assay using human peripheral-blood CD34(+) cells, the SCF moiety of rhTPO-SCF worked in a synergistic way to augment the colony number and exhibited a higher potential to stimulate megakaryocyte colony growth. According to the results of EMSA (electrophoretic mobility-shift assay) and semi-quantitative RT (reverse transcriptase)-PCR, the synergistic effects of the SCF moiety were also reflected in increased STAT5 (signal transducer and activator of transcription 5) DNA binding and enhanced up-regulation of p21 expression in Mo7e cells treated by rhTPO-SCF, suggesting that rhTPO-SCF could be more potent in promoting megakaryocyte proliferation and differentiation.

  19. Stimulating Neoblast-Like Cell Proliferation in Juvenile Fasciola hepatica Supports Growth and Progression towards the Adult Phenotype In Vitro.

    Science.gov (United States)

    McCusker, Paul; McVeigh, Paul; Rathinasamy, Vignesh; Toet, Hayley; McCammick, Erin; O'Connor, Anna; Marks, Nikki J; Mousley, Angela; Brennan, Gerard P; Halton, David W; Spithill, Terry W; Maule, Aaron G

    2016-09-01

    Fascioliasis (or fasciolosis) is a socioeconomically important parasitic disease caused by liver flukes of the genus Fasciola. Flukicide resistance has exposed the need for new drugs and/or a vaccine for liver fluke control. A rapidly improving 'molecular toolbox' for liver fluke encompasses quality genomic/transcriptomic datasets and an RNA interference platform that facilitates functional genomics approaches to drug/vaccine target validation. The exploitation of these resources is undermined by the absence of effective culture/maintenance systems that would support in vitro studies on juvenile fluke development/biology. Here we report markedly improved in vitro maintenance methods for Fasciola hepatica that achieved 65% survival of juvenile fluke after 6 months in standard cell culture medium supplemented with 50% chicken serum. We discovered that this long-term maintenance was dependent upon fluke growth, which was supported by increased proliferation of cells resembling the "neoblast" stem cells described in other flatworms. Growth led to dramatic morphological changes in juveniles, including the development of the digestive tract, reproductive organs and the tegument, towards more adult-like forms. The inhibition of DNA synthesis prevented neoblast-like cell proliferation and inhibited growth/development. Supporting our assertion that we have triggered the development of juveniles towards adult-like fluke, mass spectrometric analyses showed that growing fluke have an excretory/secretory protein profile that is distinct from that of newly-excysted juveniles and more closely resembles that of ex vivo immature and adult fluke. Further, in vitro maintained fluke displayed a transition in their movement from the probing behaviour associated with migrating stage worms to a slower wave-like motility seen in adults. Our ability to stimulate neoblast-like cell proliferation and growth in F. hepatica underpins the first simple platform for their long-term in vitro study

  20. Inhibition of chemokine (C-C motif receptor 7 sialylation suppresses CCL19-stimulated proliferation, invasion and anti-anoikis.

    Directory of Open Access Journals (Sweden)

    Mei-Lin Su

    Full Text Available Chemokine (C-C motif receptor 7 (CCR7 is involved in lymph-node homing of naive and regulatory T cells and lymphatic metastasis of cancer cells. Sialic acids comprise a group of monosaccharide units that are added to the terminal position of the oligosaccharide chain of glycoproteins by sialyation. Recent studies suggest that aberrant sialylation of receptor proteins contributes to proliferation, motility, and drug resistance of cancer cells. In this study, we addressed whether CCR7 is a sialylated receptor protein and tried to elucidate the effect of sialylation in the regulation of signal transduction and biological function of CCR7. Our results demonstrated that α-2, 3-sialyltransferase which catalyze sialylation reaction in vivo was overexpressed in breast tumor tissues and cell lines. Lectin blot analysis clearly demonstrated that CCR7 receptor was sialyated in breast cancer cells. Chemokine (C-C motif ligand 19 (CCL19, the cognate ligand for CCR7, induced the activation of extracellular signal-regulated kinase (ERK and AKT signaling and increased the expression of cell cycle regulatory proteins and proliferation of breast cancer cells. When cells were pre-treated with a sialyltransferase inhibitor AL10 or sialidase, CCL19-induced cell growth was significantly suppressed. CCL19 also increased invasion and prevented anoikis by up-regulating pro-survival proteins Bcl-2 and Bcl-xL. Inhibition of sialylation by AL10 totally abolished these effects. Finally, we showed that AL10 inhibited tumorigenicity of breast cancer in experimental animals. Taken together, we demonstrate for the first time that CCR7 receptor is a sialylated protein and sialylation is important for the paracrine stimulation by its endogenous ligand CCL19. In addition, inhibition of aberrant sialylation of CCR7 suppresses proliferation and invasion and triggers anoikis in breast cancer cells. Targeting of sialylation enzymes may be a novel strategy for breast cancer treatment.

  1. Diabetic HDL Is Dysfunctional in Stimulating Endothelial Cell Migration and Proliferation Due to Down Regulation of SR-BI Expression

    Science.gov (United States)

    Pan, Bing; Ma, Yijing; Ren, Hui; He, Yubin; Wang, Yongyu; Lv, Xiaofeng; Liu, Donghui; Ji, Liang; Yu, Baoqi; Wang, Yuhui; Chen, Y. Eugene; Pennathur, Subramaniam; Smith, Jonathan D.; Liu, George; Zheng, Lemin

    2012-01-01

    Background Diabetic HDL had diminished capacity to stimulate endothelial cell (EC) proliferation, migration, and adhesion to extracellular matrix. The mechanism of such dysfunction is poorly understood and we therefore sought to determine the mechanistic features of diabetic HDL dysfunction. Methodology/Principal Findings We found that the dysfunction of diabetic HDL on human umbilical vein endothelial cells (HUVECs) was associated with the down regulation of the HDL receptor protein, SR-BI. Akt-phosphorylation in HUVECs was induced in a biphasic manner by normal HDL. While diabetic HDL induced Akt phosphorylation normally after 20 minutes, the phosphorylation observed 24 hours after diabetic HDL treatment was reduced. To determine the role of SR-BI down regulation on diminished EC responses of diabetic HDL, Mouse aortic endothelial cells (MAECs) were isolated from wild type and SR-BI (−/−) mice, and treated with normal and diabetic HDL. The proliferative and migratory effects of normal HDL on wild type MAECs were greatly diminished in SR-BI (−/−) cells. In contrast, response to diabetic HDL was impaired in both types suggesting diminished effectiveness of diabetic HDL on EC proliferation and migration might be due to the down regulation of SR-BI. Additionally, SR-BI down regulation diminishes diabetic HDL’s capacity to activate Akt chronically. Conclusions/Significance Diabetic HDL was dysfunctional in promoting EC proliferation, migration, and adhesion to matrix which was associated with the down-regulation of SR-BI. Additionally, SR-BI down regulation diminishes diabetic HDL’s capacity to activate Akt chronically. PMID:23133640

  2. Cyclin-dependent kinase phosphorylation of RUNX1/AML1 on 3 sites increases transactivation potency and stimulates cell proliferation

    Science.gov (United States)

    Zhang, Linsheng; Fried, Florence B.; Guo, Hong

    2008-01-01

    RUNX1/AML1 regulates lineage-specific genes during hematopoiesis and stimulates G1 cell-cycle progression. Within RUNX1, S48, S303, and S424 fit the cyclin-dependent kinase (cdk) phosphorylation consensus, (S/T)PX(R/K). Phosphorylation of RUNX1 by cdks on serine 303 was shown to mediate destabilization of RUNX1 in G2/M. We now use an in vitro kinase assay, phosphopeptide-specific antiserum, and the cdk inhibitor roscovitine to demonstrate that S48 and S424 are also phosphorylated by cdk1 or cdk6 in hematopoietic cells. S48 phosphorylation of RUNX1 paralleled total RUNX1 levels during cell-cycle progression, S303 was more effectively phosphorylated in G2/M, and S424 in G1. Single, double, and triple mutation of the cdk sites to the partially phosphomimetic aspartic acid mildly reduced DNA affinity while progressively increasing transactivation of a model reporter. Mutation to alanine increased DNA affinity, suggesting that in other gene or cellular contexts phosphorylation of RUNX1 by cdks may reduce transactivation. The tripleD RUNX1 mutant rescued Ba/F3 cells from inhibition of proliferation by CBFβ-SMMHC more effectively than the tripleA mutant. Together these findings indicate that cdk phosphorylation of RUNX1 potentially couples stem/progenitor proliferation and lineage progression. PMID:18003885

  3. Chemerin Stimulates Vascular Smooth Muscle Cell Proliferation and Carotid Neointimal Hyperplasia by Activating Mitogen-Activated Protein Kinase Signaling

    Science.gov (United States)

    Xiong, Wei; Luo, Yu; Wu, Lin; Liu, Feng; Liu, Huadong; Li, Jianghua; Liao, Bihong; Dong, Shaohong

    2016-01-01

    Vascular neointimal hyperplasia and remodeling arising from local inflammation are characteristic pathogeneses of proliferative cardiovascular diseases, such as atherosclerosis and post angioplasty restenosis. The molecular mechanisms behind these pathological processes have not been fully determined. The adipokine chemerin is associated with obesity, metabolism, and control of inflammation. Recently, chemerin has gained increased attention as it was found to play a critical role in the development of cardiovascular diseases. In this study, we investigated the effects of chemerin on the regulation of vascular smooth muscle cells and carotid neointimal formation after angioplasty. We found that circulating chemerin levels increased after carotid balloon injury, and that knockdown of chemerin significantly inhibited the proliferative aspects of vascular smooth muscle cells induced by platelet-derived growth factor-BB and pro-inflammatory chemokines in vitro as well as prohibited carotid neointimal hyperplasia and pro-inflammatory chemokines in vivo after angioplasty. Additionally, inhibition of chemerin down-regulated the expression of several proteins, including phosphorylated p38 mitogen-activated protein kinase, phosphorylated extracellular signal regulated kinase 1/2, nuclear factor-kappa B p65, and proliferation cell nuclear antigen. The novel finding of this study is that chemerin stimulated vascular smooth muscle cells proliferation and carotid intimal hyperplasia through activation of the mitogen-activated protein kinase signaling pathway, which may lead to vascular inflammation and remodeling, and is relevant to proliferative cardiovascular diseases. PMID:27792753

  4. Chondroitin sulfate proteoglycan protein is stimulated by interleukin 11 and promotes endometrial epithelial cancer cell proliferation and migration.

    Science.gov (United States)

    Winship, Amy; Van Sinderen, Michelle; Heffernan-Marks, Ariella; Dimitriadis, Eva

    2017-03-01

    Endometrial cancer is the most common gynecological cancer. We identified interleukin 11 (IL11) as a critical mediator of endometrial tumourigenesis and demonstrated that IL11 regulates chondroitin sulfate proteoglycan (CSPG4) in human placental trophoblasts. CSPG4 is a cell membrane protein overexpressed in numerous human cancers, although its role in endometrial cancer has not been investigated. We examined CSPG4 expression and localization in primary human type I endometrioid grade (G) 1-3 tumours by qPCR and immunohistochemistry and determined whether IL11 stimulated CSPG4. IL11 upregulated CSPG4 mRNA in HEC1A (G2-derived endometrial epithelial cancer cell line) cells. IL11 administration to BALB/c nude mice enhanced HEC1A xenograft tumour growth and increased CSPG4 protein in tumours. CSPG4 mRNA was unchanged between human G1-3 endometrial cancer and control tissues. CSPG4 protein levels were elevated in the epithelium of G2 and G3 endometrial cancer and in the tumour-associated stroma of G3 tumour tissues compared to proliferative phase or post-menopausal endometrium. CSPG4 knockdown by siRNA reduced HEC1A proliferation and migration in vitro and reduced gene expression of the key epithelial-to-mesenchymal transition (EMT) regulator SNAIL. Our data suggest that CSPG4 inhibition may impair endometrial cancer progression by reducing cancer cell proliferation, migration and potentially EMT.

  5. Acemannan, an extracted product from Aloe vera, stimulates dental pulp cell proliferation, differentiation, mineralization, and dentin formation.

    Science.gov (United States)

    Jittapiromsak, Nawaporn; Sahawat, Dusida; Banlunara, Wijit; Sangvanich, Polkit; Thunyakitpisal, Pasutha

    2010-06-01

    This study investigated the effect of acemannan (Aloe vera gel polysaccharide) on dentin formation. Primary human dental pulp cells were treated with acemannan. New DNA synthesis, bone morphogenetic protein-2, alkaline phosphatase activity, dentin sialoprotein expression, and mineralization were determined by [(3)H]-thymidine incorporation, enzyme-linked immunosorbent assay, biochemical assay, western blotting, and Alizarin Red staining, respectively. Then the upper first molars of 24 male Sprague Dawley rats were intentionally exposed and capped with either acemannan or calcium hydroxide. At day 28, the teeth were histopathologically examined and evaluated for the degree of inflammation, dentin bridge formation, and pulp tissue organization. The results revealed that acemannan significantly increased pulp cell proliferation, bone morphogenetic protein-2, alkaline phosphatase activity, dentin sialoprotein expression, and mineralization, compared with the untreated group. The acemannan-treated group also exhibited a complete homogeneous calcified dentin bridge and good pulp tissue organization, whereas neither was detected in the calcium hydroxide-treated and sham groups. In the acemannan-treated group, either mild or no inflammation was found, whereas the other groups had various degrees of inflammation. The data suggest that acemannan promotes dentin formation by stimulating primary human dental pulp cell proliferation, differentiation, extracellular matrix formation, and mineralization. Acemannan also has pulpal biocompatibility and promotes soft tissue organization.

  6. HIV-1 Tat regulates the expression of the dcw operon and stimulates the proliferation of bacteria.

    Science.gov (United States)

    Wei, Jinsong; Zhang, Yumin; Knapp, Pamela E; Zhao, Tianyong

    2016-01-01

    Infections of pathogenic bacteria are very common in acquired immunodeficiency syndrome (AIDS) patients. However, the biological effects of HIV-1 Tat on bacteria are incompletely understood. In this study, HIV-1 Tat was expressed in Escherichia coli and Pseudomonas aeruginosa (PA01) to investigate its biological effects on bacteria. Bacterial cells expressing either HIV-1 Tat1-86 (Tat1-86) or HIV-1 Tat1-72 (Tat1-72) grow significantly faster than those with either only an empty vector or an unrelated control (GFP or Rluc). Supplementation of purified HIV-1 Tat1-86 or Tat1-101 protein into bacterial culture medium stimulated the growth of both E. coli and PA01. The expression profile of certain cell division-associated genes, such as those in the division cell wall (dcw) operon (ftsA, ftsQ, ftsW and ftsZ), yafO and zipA, was altered in HIV-1 Tat1-86 expressing E. coli BL21(DE3). Furthermore, the expression of firefly luciferase (Fluc) reporter gene, when engineered for control by the dcw promoter and terminator, was enhanced by HIV-1 Tat in E. coli, confirming that HIV-1 Tat transcriptionally regulates the expression of the dcw operon. The finding that HIV-1 Tat stimulates bacterial growth whether it is produced intracellularly or applied extracellularly may have relevance for HIV patients who are highly susceptible to opportunistic bacterial infections. Contents category: Viruses -Retroviruses. The GenBank accession number for the sequence of HIV-1 Tat1-86 is AF324439.1.

  7. Kv3.1 channels stimulate adult neural precursor cell proliferation and neuronal differentiation.

    Science.gov (United States)

    Yasuda, Takahiro; Cuny, Hartmut; Adams, David J

    2013-05-15

    Adult neural stem/precursor cells (NPCs) play a pivotal role in neuronal plasticity throughout life. Among ion channels identified in adult NPCs, voltage-gated delayed rectifier K(+) (KDR) channels are dominantly expressed. However, the KDR channel subtype and its physiological role are still undefined. We used real-time quantitative RT-PCR and gene knockdown techniques to identify a major functional KDR channel subtype in adult NPCs. Dominant mRNA expression of Kv3.1, a high voltage-gated KDR channel, was quantitatively confirmed. Kv3.1 gene knockdown with specific small interfering RNAs (siRNA) for Kv3.1 significantly inhibited Kv3.1 mRNA expression by 63.9% (P Kv3.1 is the subtype responsible for producing KDR channel outward currents. Resting membrane properties, such as resting membrane potential, of NPCs were not affected by Kv3.1 expression. Kv3.1 knockdown with 300 nm siRNA inhibited NPC growth (increase in cell numbers) by 52.9% (P Kv3.1 knockdown also significantly reduced neuronal differentiation by 31.4% (P Kv3.1 is a dominant functional KDR channel subtype expressed in adult NPCs and plays key roles in NPC proliferation and neuronal lineage commitment during differentiation.

  8. Oxysterols stimulate Sonic hedgehog signal transduction and proliferation of medulloblastoma cells.

    Science.gov (United States)

    Corcoran, Ryan B; Scott, Matthew P

    2006-05-30

    Sterol synthesis is required for Sonic hedgehog (Shh) signal transduction. Errors in Shh signal transduction play important roles in the formation of human tumors, including medulloblastoma (MB). It is not clear which products of sterol synthesis are necessary for Shh signal transduction or how they act. Here we show that cholesterol or specific oxysterols are the critical products of sterol synthesis required for Shh pathway signal transduction in MB cells. In MB cells, sterol synthesis inhibitors reduce Shh target gene transcription and block Shh pathway-dependent proliferation. These effects of sterol synthesis inhibitors can be reversed by exogenous cholesterol or specific oxysterols. We also show that certain oxysterols can maximally activate Shh target gene transcription through the Smoothened (Smo) protein as effectively as the known Smo full agonist, SAG. Thus, sterols are required and sufficient for Shh pathway activation. These results suggest that oxysterols may be critical regulators of Smo, and thereby Shh signal transduction. Inhibition of Shh signaling by sterol synthesis inhibitors may offer a novel approach to the treatment of MB and other Shh pathway-dependent human tumors.

  9. Vanadyl Sulfate Treatment Stimulates Proliferation and Regeneration of Beta Cells in Pancreatic Islets

    Directory of Open Access Journals (Sweden)

    Samira Missaoui

    2014-01-01

    Full Text Available We examined the effects of vanadium sulfate (VOSO4 treatment at 5 and 10 mg/kg for 30 days on endocrine pancreas activity and histology in nondiabetic and STZ-induced diabetic rats. In diabetic group, blood glucose levels significantly increased while insulinemia level markedly decreased. At the end of treatment, VOSO4 at a dose of 10 mg/Kg normalized blood glucose level in diabetic group, restored insulinemia, and significantly improved insulin sensitivity. VOSO4 also increased in a dose-dependent manner the number of insulin immunopositive beta cells in pancreatic islets of nondiabetic rats. Furthermore, in the STZ-diabetic group, the decrease in the number of insulin immunopositive beta cells was corrected to reach the control level mainly with the higher dose of vanadium. Therefore, VOSO4 treatment normalized plasma glucose and insulin levels and improved insulin sensitivity in STZ-experimental diabetes and induced beta cells proliferation and/or regeneration in normal or diabetic rats.

  10. The Use Of Laser Irradiation To Stimulate Adipose Derived Stem Cell Proliferation And Differentiation For Use In Autologous Grafts

    Science.gov (United States)

    Abrahamse, Heidi

    2009-09-01

    Stem cells are characterized by the qualities of self-renewal, long term viability, and the ability to differentiate into various cell types. Historically, stem cells have been isolated from the inner cell mass of blastocysts and harvesting these cells resulted in the death of the embryo leading to religious, political and ethical issues. The identification and subsequent isolation of adult stem cells from bone marrow stroma have been welcomed as an alternate source for stem cells. The clinical use of Mesenchymal Stem Cells (MSCs) presented problems such as limited cell number, pain and morbidity upon isolation. Adipose tissue is derived from the mesenchyme, is easily isolated, a reliable source of stem cells and able to differentiate into different cell types including smooth muscle. Over the past few years, the identification and characterization of stem cells has led the potential use of these cells as a promising alternative to cell replacement therapy. Smooth muscle is a major component of human tissues and is essential for the normal functioning of many different organs. Low intensity laser irradiation has been shown to increase viability, protein expression and migration of stem cells in vitro, and to stimulate proliferation of various types of stem cells. In addition, the use of laser irradiation to stimulate differentiation in the absence of growth factors has also been demonstrated in normal human neural progenitor cells (NHNPCs) in vitro where NHNPCs are not only capable of being sustained by light in the absence of growth factors, but that they are also able to differentiate normally as assessed by neurite formation. Our work has focused on the ability of laser irradiation to proliferate adipose derived stem cells (ADSCs), maintain ADSC character and increase the rate and maintenance of differentiation of ADSCs into smooth muscle and skin fibroblast cells. Current studies are also investigating the effect of different irradiation wavelengths and

  11. Peroxisome proliferator-activated receptor-gamma abrogates Smad-dependent collagen stimulation by targeting the p300 transcriptional coactivator.

    Science.gov (United States)

    Ghosh, Asish K; Bhattacharyya, Swati; Wei, Jun; Kim, Suyeon; Barak, Yaacov; Mori, Yasuji; Varga, John

    2009-09-01

    Ligands of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) abrogate the stimulation of collagen gene transcription induced by transforming growth factor-beta (TGF-beta). Here, we delineate the mechanisms underlying this important novel physiological function for PPAR-gamma in connective tissue homeostasis. First, we demonstrated that antagonistic regulation of TGF-beta activity by PPAR-gamma ligands involves cellular PPAR-gamma, since 15-deoxy-Delta12,14-prostaglandin J(2) (15d-PGJ(2)) failed to block TGF-beta-induced responses in either primary cultures of PPAR-gamma-null murine embryonic fibroblasts, or in normal human skin fibroblasts with RNAi-mediated knockdown of PPAR-gamma. Next, we examined the molecular basis underlying the abrogation of TGF-beta signaling by PPAR-gamma in normal human fibroblasts in culture. The results demonstrated that Smad-dependent transcriptional responses were blocked by PPAR-gamma without preventing Smad2/3 activation. In contrast, the interaction between activated Smad2/3 and the transcriptional coactivator and histone acetyltransferase p300 induced by TGF-beta, and the accumulation of p300 on consensus Smad-binding DNA sequences and histone H4 hyperacetylation at the COL1A2 locus, were all prevented by PPAR-gamma. Wild-type p300, but not a mutant form of p300 lacking functional histone acetyltransferase, was able to restore TGF-beta-induced stimulation of COL1A2 in the presence of PPAR-gamma ligands. Collectively, these results indicate that PPAR-gamma blocked Smad-mediated transcriptional responses by preventing p300 recruitment and histone H4 hyperacetylation, resulting in the inhibition of TGF-beta-induced collagen gene expression. Pharmacological activation of PPAR-gamma thus may represent a novel therapeutic approach to target p300-dependent TGF-beta profibrotic responses such as stimulation of collagen gene expression.

  12. Hypoxia upregulates Bcl-2 expression and suppresses interferon-gamma induced antiangiogenic activity in human tumor derived endothelial cells.

    LENUS (Irish Health Repository)

    Wang, Jiang Huai

    2012-02-03

    BACKGROUND: Hypoxia in solid tumors potentially stimulates angiogenesis by promoting vascular endothelial growth factor (VEGF) production and upregulating VEGF receptor expression. However, it is unknown whether hypoxia can modulate the effect of anti-angiogenic treatment on tumor-derived endothelium. METHODS: Human tumor-derived endothelial cells (HTDEC) were freshly isolated from surgically removed human colorectal tumors by collagenase\\/DNase digestion and Percol gradient sedimentation. Cell proliferation was assessed by measuring BrdU incorporation, and capillary tube formation was measured using Matrigel. Cell apoptosis was assessed by flow cytometry and ELISA, and Bcl-2 expression was detected by Western blot analysis. RESULTS: Under aerobic culture conditions (5% CO2 plus 21% O2) HTDEC expressed less Bcl-2 and were more susceptible to IFN-gamma-induced apoptosis with significant reductions in both cell proliferation and capillary tube formation, when compared with normal human macrovascular and microvascular EC. Following exposure of HTDEC to hypoxia (5% CO2 plus 2% O2), IFN-gamma-induced cell apoptosis, and antiangiogenic activity (i.e. an inhibition in cell proliferation and capillary tube formation) in HTDEC were markedly attenuated. This finding correlated with hypoxia-induced upregulation of Bcl-2 expression in HTDEC. CONCLUSIONS: These results indicate that hypoxia can protect HTDEC against IFN-gamma-mediated cell death and antiangiogenic activity, and suggest that improvement of tumor oxygenation may potentiate the efficacy of anti-cancer therapies specifically targeting the inhibition of tumor angiogenesis.

  13. MYC gene delivery to adult mouse utricles stimulates proliferation of postmitotic supporting cells in vitro.

    Directory of Open Access Journals (Sweden)

    Joseph C Burns

    Full Text Available The inner ears of adult humans and other mammals possess a limited capacity for regenerating sensory hair cells, which can lead to permanent auditory and vestibular deficits. During development and regeneration, undifferentiated supporting cells within inner ear sensory epithelia can self-renew and give rise to new hair cells; however, these otic progenitors become depleted postnatally. Therefore, reprogramming differentiated supporting cells into otic progenitors is a potential strategy for restoring regenerative potential to the ear. Transient expression of the induced pluripotency transcription factors, Oct3/4, Klf4, Sox2, and c-Myc reprograms fibroblasts into neural progenitors under neural-promoting culture conditions, so as a first step, we explored whether ectopic expression of these factors can reverse supporting cell quiescence in whole organ cultures of adult mouse utricles. Co-infection of utricles with adenoviral vectors separately encoding Oct3/4, Klf4, Sox2, and the degradation-resistant T58A mutant of c-Myc (c-MycT58A triggered significant levels of supporting cell S-phase entry as assessed by continuous BrdU labeling. Of the four factors, c-MycT58A alone was both necessary and sufficient for the proliferative response. The number of BrdU-labeled cells plateaued between 5-7 days after infection, and then decreased ~60% by 3 weeks, as many cycling cells appeared to enter apoptosis. Switching to differentiation-promoting culture medium at 5 days after ectopic expression of c-MycT58A temporarily attenuated the loss of BrdU-labeled cells and accompanied a very modest but significant expansion of the sensory epithelium. A small number of the proliferating cells in these cultures labeled for the hair cell marker, myosin VIIA, suggesting they had begun differentiating towards a hair cell fate. The results indicate that ectopic expression of c-MycT58A in combination with methods for promoting cell survival and differentiation may restore

  14. c-Ski inhibits the proliferation of vascular smooth muscle cells via suppressing Smad3 signaling but stimulating p38 pathway.

    Science.gov (United States)

    Li, Jun; Li, Ping; Zhang, Yan; Li, Gong-Bo; Zhou, Yuan-Guo; Yang, Kang; Dai, Shuang-Shuang

    2013-01-01

    Proliferation of vascular smooth muscle cells (VSMCs) plays key roles in the progression of intimal hyperplasia, but the molecular mechanisms that trigger VSMC proliferation after vascular injury remain unclear. c-Ski, a co-repressor of transforming growth factor β (TGF-β)/Smad signaling, was detected to express in VSMC of rat artery. During the course of arterial VSMC proliferation induced by balloon injury in rat, the endogenous protein expressions of c-Ski decreased markedly in a time-dependent manner. In vivo c-Ski gene delivery was found to significantly suppress balloon injury-induced VSMC proliferation and neointima formation. Further investigation in A10 rat aortic smooth muscle cells demonstrated that overexpression of c-Ski gene inhibited TGF-β1 (1 ng/ml)-induced A10 cell proliferation while knockdown of c-Ski by RNAi enhanced the stimulatory effect of TGF-β1 on A10 cell growth. Western blot for signaling detection showed that suppression of Smad3 phosphorylation while stimulating p38 signaling associated with upregulation of cyclin-dependent kinase inhibitors p21 and p27 was responsible for the inhibitory effect of c-Ski on TGF-β1-induced VSMC proliferation. These data suggest that the decrease of endogenous c-Ski expression is implicated in the progression of VSMC proliferation after arterial injury and c-Ski administration represents a promising role for treating intimal hyperplasia via inhibiting the proliferation of VSMC.

  15. Paeonol Inhibits Proliferation of Vascular Smooth Muscle Cells Stimulated by High Glucose via Ras-Raf-ERK1/2 Signaling Pathway in Coculture Model

    Directory of Open Access Journals (Sweden)

    Junjun Chen

    2014-01-01

    Full Text Available Paeonol (Pae has been previously reported to protect against atherosclerosis (AS by inhibiting vascular smooth muscle cell (VSMC proliferation or vascular endothelial cell (VEC injury. But studies lack how VSMCs and VECs interact when Pae plays a role. The current study was based on a coculture model of VSMCs and VECs to investigate the protective mechanisms of Pae on atherosclerosis (AS by determining the secretory function of VECs and proliferation of VSMCs focusing on the Ras-Raf-ERK1/2 signaling pathway. VECs were stimulated by high glucose. Our data showed that high concentration (35.5 mM of glucose induced damage in VECs. Injury of VECs stimulated VSMC proliferation in the coculture model. Pae (120 μM decreased vascular endothelial growth factor (VEGF and platelet derivative growth factor B (PDGF-B release from VECs and inhibited overexpression of Ras, P-Raf, and P-ERK proteins in VSMCs. The results indicate that diabetes modulates the inflammatory response in VECs to stimulate VSMC proliferation and promote the development of AS. Pae was beneficial by inhibiting the inflammatory effects of VECs on VSMC proliferation. This study suggests the inhibitory mechanism of Pae due to the inhibition of VEGF and PDGF-B secretion in VECs and Ras-Raf-ERK1/2 signaling pathway in VSMCs.

  16. Human periodontal ligament fibroblasts stimulated by nanocrystalline hydroxyapatite paste or enamel matrix derivative. An in vitro assessment of PDL attachment, migration, and proliferation

    NARCIS (Netherlands)

    Kasaj, A.; Willershausen, B.; Junker, R.; Stratul, S.I.; Schmidt, M.

    2012-01-01

    We determined the effects of soluble or coated nanocrystalline hydroxyapatite paste (nano-HA) and enamel matrix derivative (EMD) on proliferation, adhesion, and migration of periodontal ligament fibroblasts (PDLs). Cultured PDLs were stimulated with nano-HA paste or EMD in a soluble form or were

  17. Impact of infertility regimens on breast cancer cells: follicle-stimulating hormone and luteinizing hormone lack a direct effect on breast cell proliferation in vitro.

    Science.gov (United States)

    Boukaidi, Samir Alexandre; Cooley, Anne; Hardy, Ashley; Matthews, Laura; Zelivianski, Stanislav; Jeruss, Jacqueline S

    2012-02-01

    To examine the impact of hormones used for controlled ovarian hyperstimulation (COH) on normal and malignant breast cell growth and proliferation. In vitro study of cultured normal and malignant breast cell lines. Academic medical center. None. Normal and malignant breast cell lines cultured in two- and three-dimensional (2D and 3D) systems and treated with follicle-stimulating hormone (FSH), luteinizing hormone (LH), or FSH with LH or human chorionic gonadotropin (hCG). Effects of treatment on cell proliferation in 2D culture using the MTS assay and on colony growth in 3D culture. Compared with untreated cells, normal MCF-10A cells showed a decrease in proliferation and colony size when exposed to a combination of FSH and hCG. The HCC 1937 cells treated with FSH and LH also showed a decrease in colony growth but no change in proliferation. None of the treatments had an effect on the proliferation or colony size of the MCF-7 cells. Follicle-stimulating hormone, LH, and hCG do not appear to cause an increase in cell proliferation or colony growth in either normal or malignant mammary epithelial cell lines. The potential risk for mammary cell transformation associated with these agents may be related to indirect endocrine effects on breast cell physiology. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  18. Estradiol-17beta stimulates proliferation of mouse embryonic stem cells: involvement of MAPKs and CDKs as well as protooncogenes.

    Science.gov (United States)

    Han, Ho Jae; Heo, Jung Sun; Lee, Yun Jung

    2006-04-01

    Although the importance of estradiol-17beta (E(2)) in many physiological processes has been reported, to date no researchers have investigated the effects of E(2) on embryonic stem (ES) cell proliferation. Therefore, in the present study, we have examined the effect of E(2) on the DNA synthesis of murine ES (ES-E14TG2a) cells and its related signaling pathways. The results of this study show that E(2) (10(-9) M) significantly increased [(3)H]thymidine incorporation at >4 h and that E(2) (>10(-12) M) induced an increase of [(3)H]thymidine incorporation after 8-h incubation. Moreover, E(2) (>10(-12) M) also increased 5'-bromo-2'-deoxyuridine (BrdU) incorporation and cell number. Indeed, E(2) stimulated estrogen receptor (ER)-alpha and -beta protein levels and increased mRNA expression levels of protooncogenes (c-fos, c-jun, and c-myc). Tamoxifen (antiestrogen) completely inhibited E(2)-induced increases in [(3)H]thymidine incorporation. In addition, estradiol-6-O-carboxymethyl oxime-BSA (E(2)-BSA; 10(-9) M) increased [(3)H]thymidine incorporation at >1 h, and E(2)-BSA (>10(-12) M) increased [(3)H]thymidine incorporation after 1-h incubation. E(2)-BSA-induced increase in BrdU incorporation also occurred in a dose-dependent manner. Tamoxifen had no effect on E(2)-BSA-induced increase of [(3)H]thymidine incorporation. Also, E(2) and E(2)-BSA displayed maximal phosphorylation of p44/42 MAPKs at 10 and 5 min, respectively. E(2) increased cyclins D1 and E as well as cyclin-dependent kinase (CDK)2 and CDK4. In contrast, E(2) decreased the levels of p21(cip1) and p27(kip1) (CDK-inhibitory proteins). Increases of these cell cycle regulators were blocked by 10(-5) M PD-98059 (MEK inhibitor). Moreover, E(2)-induced increase of [(3)H]thymidine incorporation was inhibited by PD-98059 or butyrolactone I (CDK2 inhibitor). In conclusion, estradiol-17beta stimulates the proliferation of murine ES cells, and this action is mediated by MAPKs, CDKs, or protooncogenes.

  19. Effects of manganese and hypoxia on coelomocyte renewal in the echinoderm, Asterias rubens (L.)

    Energy Technology Data Exchange (ETDEWEB)

    Oweson, Carolina [Department of Marine Ecology, University of Gothenburg, Kristineberg 566, SE-450 34 Fiskebaeckskil (Sweden); Li Chenghua; Soederhaell, Irene [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18a, SE-752 36 Uppsala (Sweden); Hernroth, Bodil, E-mail: bodil.hernroth@marecol.gu.se [Royal Swedish Academy of Sciences, Kristineberg 566, SE-450 34 Fiskebaeckskil (Sweden); Biomedical Group, Kristianstad University, SE-291 88 Kristianstad (Sweden)

    2010-10-01

    Manganese (Mn) is a naturally abundant metal and particularly so in soft-bottom oceanic sediments where it generally occurs bound in a four-valent colloidal state as MnO{sub 2}. When hypoxic conditions occur in bottom waters, the metal reduces to the bioavailable ion Mn{sup 2+} and can reach concentrations known to have immunotoxic effects in the crustacean Nephrops norvegicus, reducing numbers of circulating haemocytes as a consequence. However, we have previously shown that Mn seems to have a contrasting effect on the echinoderm Asterias rubens in which it triggers the proliferation of haematopoietic cells and increases coelomocyte numbers. Since elevated Mn levels mostly co-occur with hypoxia in nature, here we investigated whether hypoxia has a negative effect on haematopoiesis. Proliferation and differentiation of coelomocytes and cells in the coelomic epithelium of A. rubens were compared after 3 days of exposure to realistic levels of Mn, hypoxia or a combination of these two parameters. We can confirm that Mn elevated numbers of coelomocytes and increased proliferation of epithelial cells, but hypoxia did not affect these levels. However, hypoxia did affect differentiation of these cells as judged by investigating the expression of a Runt domain transcription factor, which was also cloned and sequenced. Through comparative quantification using a real time PCR technique, we found that exposure to hypoxia had a clearly stimulating effect on mRNA expression of Runt gene in both coelomocytes and epithelial cells. These results indicate that during hypoxic conditions the composition of coelomocyte sub-populations changed.

  20. Protein kinase D1 mediates stimulation of DNA synthesis and proliferation in intestinal epithelial IEC-18 cells and in mouse intestinal crypts.

    Science.gov (United States)

    Sinnett-Smith, James; Rozengurt, Nora; Kui, Robert; Huang, Carlos; Rozengurt, Enrique

    2011-01-07

    We examined whether protein kinase D1 (PKD1), the founding member of a new protein kinase family, plays a critical role in intestinal epithelial cell proliferation. Our results demonstrate that PKD1 activation is sustained, whereas that of PKD2 is transient in intestinal epithelial IEC-18 stimulated with the G(q)-coupled receptor agonists angiotensin II or vasopressin. PKD1 gene silencing utilizing small interfering RNAs dramatically reduced DNA synthesis and cell proliferation in IEC-18 cells stimulated with G(q)-coupled receptor agonists. To clarify the role of PKD1 in intestinal epithelial cell proliferation in vivo, we generated transgenic mice that express elevated PKD1 protein in the intestinal epithelium. Transgenic PKD1 exhibited constitutive catalytic activity and phosphorylation at the activation loop residues Ser(744) and Ser(748) and on the autophosphorylation site, Ser(916). To examine whether PKD1 expression stimulates intestinal cell proliferation, we determined the rate of crypt cell DNA synthesis by detection of 5-bromo-2-deoxyuridine incorporated into the nuclei of crypt cells of the ileum. Our results demonstrate a significant increase (p < 0.005) in DNA-synthesizing cells in the crypts of two independent lines of PKD1 transgenic mice as compared with non-transgenic littermates. Morphometric analysis showed a significant increase in the length and in the total number of cells per crypt in the transgenic PKD1 mice as compared with the non-transgenic littermates (p < 0.01). Thus, transgenic PKD1 signaling increases the number of cells per crypt by stimulating the rate of crypt cell proliferation. Collectively, our results indicate that PKD1 plays a role in promoting cell proliferation in intestinal epithelial cells both in vitro and in vivo.

  1. Impact of interleukin-6 on hypoxia-induced pulmonary hypertension and lung inflammation in mice

    Directory of Open Access Journals (Sweden)

    Izziki Mohamed

    2009-01-01

    Full Text Available Abstract Background Inflammation may contribute to the pathogenesis of various forms of pulmonary hypertension (PH. Recent studies in patients with idiopathic PH or PH associated with underlying diseases suggest a role for interleukin-6 (IL-6. Methods To determine whether endogenous IL-6 contributes to mediate hypoxic PH and lung inflammation, we studied IL-6-deficient (IL-6-/- and wild-type (IL-6+/+ mice exposed to hypoxia for 2 weeks. Results Right ventricular systolic pressure, right ventricle hypertrophy, and the number and media thickness of muscular pulmonary vessels were decreased in IL-6-/- mice compared to wild-type controls after 2 weeks' hypoxia, although the pressure response to acute hypoxia was similar in IL-6+/+ and IL-6-/- mice. Hypoxia exposure of IL-6+/+ mice led to marked increases in IL-6 mRNA and protein levels within the first week, with positive IL-6 immunostaining in the pulmonary vessel walls. Lung IL-6 receptor and gp 130 (the IL-6 signal transducer mRNA levels increased after 1 and 2 weeks' hypoxia. In vitro studies of cultured human pulmonary-artery smooth-muscle-cells (PA-SMCs and microvascular endothelial cells revealed prominent synthesis of IL-6 by PA-SMCs, with further stimulation by hypoxia. IL-6 also markedly stimulated PA-SMC migration without affecting proliferation. Hypoxic IL-6-/- mice showed less inflammatory cell recruitment in the lungs, compared to hypoxic wild-type mice, as assessed by lung protein levels and immunostaining for the specific macrophage marker F4/80, with no difference in lung expression of adhesion molecules or cytokines. Conclusion These data suggest that IL-6 may be actively involved in hypoxia-induced lung inflammation and pulmonary vascular remodeling in mice.

  2. Fermentable carbohydrates elevate plasma enteroglucagon but high viscosity is also necessary to stimulate small bowel mucosal cell proliferation in rats.

    Science.gov (United States)

    Gee, J M; Lee-Finglas, W; Wortley, G W; Johnson, I T

    1996-02-01

    Enteroglucagon is a collective term for a small family of peptides derived from proglucagon by post-translational processing in the L-cells of the distal small intestine and colon. There is evidence that it inhibits gastric secretion, and high levels of enteroglucagon occur in plasma during intestinal adaptation, which suggests that it may also function as a trophic factor for the intestine. Certain types of soluble non-starch polysaccharide (dietary fiber) stimulate the release of enteroglucagon in rats but the mechanism is unknown. In this study we explored the importance of the viscosity and fermentability of nonabsorbed carbohydrates as determinants of plasma enteroglucagon and mucosal cell proliferation in the distal ileum of rats. Replacement of cellulose (10 g/kg) with guar gum in a semisynthetic diet led to a prompt and sustained rise in plasma enteroglucagon concentrations. Our initial hypothesis that this was a consequence of delayed nutrient absorption was disproven by the fact that hydroxypropylmethylcellulose (HPMC), a viscous but nonfermentable polysaccharide, had no effect on plasma enteroglucagon under the same conditions. In contrast, the nondigestible disaccharide lactitol led to a prolonged rise in plasma enteroglucagon, similar to that observed with guar gum. Lactitol is nonviscous, but highly fermentable, and we conclude that fermentable carbohydrate is an important stimulus for the release of enteroglucagon under our experimental conditions. There was no evidence that enteroglucagon released by this mechanism exerted trophic effects on the distal small intestinal mucosa.

  3. Downregulation of steroid receptor coactivator-2 modulates estrogen-responsive genes and stimulates proliferation of mcf-7 breast cancer cells.

    Science.gov (United States)

    Fenne, Ingvild S; Helland, Thomas; Flågeng, Marianne H; Dankel, Simon N; Mellgren, Gunnar; Sagen, Jørn V

    2013-01-01

    The p160/Steroid Receptor Coactivators SRC-1, SRC-2/GRIP1, and SRC-3/AIB1 are important regulators of Estrogen Receptor alpha (ERα) activity. However, whereas the functions of SRC-1 and SRC-3 in breast tumourigenesis have been extensively studied, little is known about the role of SRC-2. Previously, we reported that activation of the cAMP-dependent protein kinase, PKA, facilitates ubiquitination and proteasomal degradation of SRC-2 which in turn leads to inhibition of SRC-2-coactivation of ERα and changed expression of the ERα target gene, pS2. Here we have characterized the global program of transcription in SRC-2-depleted MCF-7 breast cancer cells using short-hairpin RNA technology, and in MCF-7 cells exposed to PKA activating agents. In order to identify genes that may be regulated through PKA-induced downregulation of SRC-2, overlapping transcriptional targets in response to the respective treatments were characterized. Interestingly, we observed decreased expression of several breast cancer tumour suppressor genes (e.g., TAGLN, EGR1, BCL11b, CAV1) in response to both SRC-2 knockdown and PKA activation, whereas the expression of a number of other genes implicated in cancer progression (e.g., RET, BCAS1, TFF3, CXCR4, ADM) was increased. In line with this, knockdown of SRC-2 also stimulated proliferation of MCF-7 cells. Together, these results suggest that SRC-2 may have an antiproliferative function in breast cancer cells.

  4. Effects of the protein kinase C stimulant bryostatin 1 on the proliferation and colony formation of irradiated human T-lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sung, S.J.; Lin, P.-S.; Schmidt-Ullrich, R.; Hall, C.E.; Walters, J.A.; McCrady, C.; Grant, S. [Virginia Commonwealth Univ., Richmond, VA (United States)

    1994-12-01

    The protein kinase C stimulant bryostatin 1 (Bryo) was used in examining human peripheral blood T-lymphocyte radiosensitivities in proliferation assays. Bryo was similar to PMA in inducing T-cell proliferation by the CD3, CD28 and CD69 pathways. No difference in radiosensitivities was observed in T-cells stimulated by the three independent surface antigen-mediated activation pathways. CD3 was chosen as the second signal for comparing the potencies of the three different first signals Bryo, phorbol 12-myristate, 13-acetate (PMA), and interleukin 2 (IL-2) in stimulating T-cell proliferation and in maintaining this response after radiation. Though there were radioresponse differences among various individuals, the irradiated lymphocytes consistently showed significantly greater proliferation when treated with Bryo or PMA than with IL-2. These results support the important tole of protein kinase C in T-cell radiation responses, and suggest a potential role for Bryo in enhancing T-lymphocyte survival during radiation therapy. (author).

  5. Calcineurin/nuclear factor of activated T cells-coupled vanilliod transient receptor potential channel 4 ca2+ sparklets stimulate airway smooth muscle cell proliferation.

    Science.gov (United States)

    Zhao, Limin; Sullivan, Michelle N; Chase, Marlee; Gonzales, Albert L; Earley, Scott

    2014-06-01

    Proliferation of airway smooth muscle cells (ASMCs) contributes to the remodeling and irreversible obstruction of airways during severe asthma, but the mechanisms underlying this disease process are poorly understood. Here we tested the hypothesis that Ca(2+) influx through the vanilliod transient receptor potential channel (TRPV) 4 stimulates ASMC proliferation. We found that synthetic and endogenous TRPV4 agonists increase proliferation of primary ASMCs. Furthermore, we demonstrate that Ca(2+) influx through individual TRPV4 channels produces Ca(2+) microdomains in ASMCs, called "TRPV4 Ca(2+) sparklets." We also show that TRPV4 channels colocalize with the Ca(2+)/calmodulin-dependent protein phosphatase calcineurin in ASMCs. Activated calcineurin dephosphorylates nuclear factor of activated T cells (NFAT) transcription factors cytosolic (c) to allow nuclear translocation and activation of synthetic transcriptional pathways. We show that ASMC proliferation in response to TRPV4 activity is associated with calcineurin-dependent nuclear translocation of the NFATc3 isoform tagged with green florescent protein. Our findings suggest that Ca(2+) microdomains created by TRPV4 Ca(2+) sparklets activate calcineurin to stimulate nuclear translocation of NFAT and ASMC proliferation. These findings further suggest that inhibition of TRPV4 could diminish asthma-induced airway remodeling.

  6. Stimulation of proliferation of HL60 cells by low concentrations of 12-O-tetradecanoylphorbol-13-acetate and its relationship to the mitogenic effects of insulin

    Energy Technology Data Exchange (ETDEWEB)

    Trayner, I.D.; Clemens, M.J. (St. George' s Hospital Medical School, London (United Kingdom))

    1992-03-01

    The effects of the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on the growth and differentiation of cultured human acute promyelocytic leukemia (HL60) cells have been studied using cells growing in a fully defined medium consisting of RPMI 1640 supplemented with selenium dioxide, insulin, and either transferrin or ferric citrate. High concentrations of TPA cause the expected inhibition of proliferation and induction of macrophage-like differentiation. In contrast, in cells deprived in insulin, which continue to grow at a slow rate, lower concentrations of TPA stimulate proliferation without inducing differentiation. The ability of higher concentrations of TPA to induce differentiation is independent of the presence of insulin. Low-TPA also stimulates the short-term incorporation of thymidine by three- to fourfold, as compared to a seven fold stimulation by insulin. The proliferative response to low TPA concentrations provides a useful model for dissecting the signaling pathways that control cell proliferation following stimulation by insulin and activators of protein kinase C.

  7. Participation of the PI-3K/Akt-NF-κB signaling pathways in hypoxia-induced mitogenic factor-stimulated Flk-1 expression in endothelial cells

    Directory of Open Access Journals (Sweden)

    Huang Chuanshu

    2006-07-01

    Full Text Available Abstract Background Hypoxia-induced mitogenic factor (HIMF, a lung-specific growth factor, promotes vascular tubule formation in a matrigel plug model. We initially found that HIMF enhances vascular endothelial growth factor (VEGF expression in lung epithelial cells. In present work, we tested whether HIMF modulates expression of fetal liver kinase-1 (Flk-1 in endothelial cells, and dissected the possible signaling pathways that link HIMF to Flk-1 upregulation. Methods Recombinant HIMF protein was intratracheally instilled into adult mouse lungs, Flk-1 expression was examined by immunohistochemistry and Western blot. The promoter-luciferase reporter assay and real-time RT-PCR were performed to examine the effects of HIMF on Flk-1 expression in mouse endothelial cell line SVEC 4–10. The activation of NF-kappa B (NF-κB and phosphorylation of Akt, IKK, and IκBα were examined by luciferase assay and Western blot, respectively. Results Intratracheal instillation of HIMF protein resulted in a significant increase of Flk-1 production in lung tissues. Stimulation of SVEC 4–10 cells by HIMF resulted in increased phosphorylation of IKK and IκBα, leading to activation of NF-κB. Blocking NF-κB signaling pathway by dominant-negative mutants of IKK and IκBα suppressed HIMF-induced Flk-1 upregulation. Mutation or deletion of NF-κB binding site within Flk-1 promoter also abolished HIMF-induced Flk-1 expression in SVEC 4–10 cells. Furthermore, HIMF strongly induced phosphorylation of Akt. A dominant-negative mutant of PI-3K, Δp85, as well as PI-3K inhibitor LY294002, blocked HIMF-induced NF-κB activation and attenuated Flk-1 production. Conclusion These results suggest that HIMF upregulates Flk-1 expression in endothelial cells in a PI-3K/Akt-NF-κB signaling pathway-dependent manner, and may play critical roles in pulmonary angiogenesis.

  8. Functional electrical stimulation increases neural stem/progenitor cell proliferation and neurogenesis in the subventricular zone of rats with stroke

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-hua; XIANG Yun; YAN Tie-bin; TAN Zhi-mei; LI Sheng-huo; HE Xiao-kuo

    2013-01-01

    Background Functional electrical stimulation (FES) is known to promote the recovery of motor function in rats with ischemia and to upregulate the expression of growth factors which support brain neurogenesis.In this study,we investigated whether postischemic FES could improve functional outcomes and modulate neurogenesis in the subventricular zone (SVZ) after focal cerebral ischemia.Methods Adult male Sprague-Dawley rats with permanent middle cerebral artery occlusion (MCAO) were randomly assigned to the control group,the placebo stimulation group,and the FES group.The rats in each group were further assigned to one of four therapeutic periods (1,3,7,or 14 days).FES was delivered 48 hours after the MCAO procedure and divided into two 10-minute sessions on each day of treatment with a 10-minute rest between them.Two intraperitoneal injections of bromodeoxyuridine (BrdU) were given 4 hours apart every day beginning 48 hours after the MCAO.Neurogenesis was evaluated by immunofluorescence staining.Wnt-3 which is strongly implicated in the proliferation and differentiation of neural stem cells (NSCs) was investigated by Western blotting analysis.The data wera subjected to oneway analysis of variance (ANOVA),followed by a Tukey/Kramer or Dunnett post hoc test.Results FES significantly increased the number of BrdU-positive cells and BrdU/glial flbrillary acidic protein doublepositive neural progenitor cells in the SVZ on days 7 and 14 of the treatment (P <0.05).The number of BrdU/doublecortin (DCX) double-positive migrating neuroblast cells in the ipsilateral SVZ on day 14 of the FES treatment group ((522.77±33.32) cells/mm2) was significantly increased compared with the control group ((262.58±35.11) cells/mm2,P <0.05) and the placebo group ((266.17±47.98) cells/mm2,P <0.05).However,only a few BrdU/neuron-specific nuclear protein-positive cells were observed by day 14 of the treatment.At day 7,Wnt-3 was upregulated in the ipsilateral SVZs of the rats receiving

  9. In vitro proliferation and production of cytokine and IgG by human PBMCs stimulated with polysaccharide extract from plants endemic to Gabon.

    Science.gov (United States)

    Mengome, Line Edwige; Voxeur, Aline; Akue, Jean Paul; Lerouge, Patrice

    2014-11-13

    Polysaccharides were extracted from seven plants endemic to Gabon to study their potential immunological activities. Peripheral blood mononuclear cell (PBMC) (5×10⁵ cells/mL) proliferation, cytokine and immunoglobulin G (IgG) assays were performed after stimulation with different concentrations of polysaccharide fractions compared with lipopolysaccharides (LPS) and concanavalin A (ConA) from healthy volunteers. The culture supernatants were used for cytokine and IgG detection by enzyme-linked immunosorbent assay (ELISA). The results show that pectin and hemicellulose extracts from Uvaria klainei, Petersianthus macrocarpus, Trichoscypha addonii, Aphanocalyx microphyllus, Librevillea klaineana, Neochevalierodendron stephanii and Scorodophloeus zenkeri induced production levels that were variable from one individual to another for IL-12 (3-40 pg/mL), IL-10 (6-443 pg/mL), IL-6 (7-370 pg/mL), GM-CSF (3-170 pg/mL) and IFN-γ (5-80 pg/mL). Only hemicelluloses from Aphanocalyx microphyllus produce a small amount of IgG (OD=0.034), while the proliferation of cells stimulated with these polysaccharides increased up to 318% above the proliferation of unstimulated cells. However, this proliferation of PBMCs was abolished when the pectin of some of these plants was treated with endopolygalacturonase (p<0.05), but the trend of cytokine synthesis remained the same, both before and after enzymatic treatment or saponification. This study suggests that these polysaccharides stimulate cells in a structure-dependent manner. The rhamnogalacturonan-I (RGI) fragment alone was not able to induce the proliferation of PBMC.

  10. In Vitro Proliferation and Production of Cytokine and IgG by Human PBMCs Stimulated with Polysaccharide Extract from Plants Endemic to Gabon

    Directory of Open Access Journals (Sweden)

    Line Edwige Mengome

    2014-11-01

    Full Text Available Polysaccharides were extracted from seven plants endemic to Gabon to study their potential immunological activities. Peripheral blood mononuclear cell (PBMC (5 × 105 cells/mL proliferation, cytokine and immunoglobulin G (IgG assays were performed after stimulation with different concentrations of polysaccharide fractions compared with lipopolysaccharides (LPS and concanavalin A (ConA from healthy volunteers. The culture supernatants were used for cytokine and IgG detection by enzyme-linked immunosorbent assay (ELISA. The results show that pectin and hemicellulose extracts from Uvaria klainei, Petersianthus macrocarpus, Trichoscypha addonii, Aphanocalyx microphyllus, Librevillea klaineana, Neochevalierodendron stephanii and Scorodophloeus zenkeri induced production levels that were variable from one individual to another for IL-12 (3–40 pg/mL, IL-10 (6–443 pg/mL, IL-6 (7–370 pg/mL, GM-CSF (3–170 pg/mL and IFN-γ (5–80 pg/mL. Only hemicelluloses from Aphanocalyx microphyllus produce a small amount of IgG (OD = 0.034, while the proliferation of cells stimulated with these polysaccharides increased up to 318% above the proliferation of unstimulated cells. However, this proliferation of PBMCs was abolished when the pectin of some of these plants was treated with endopolygalacturonase (p < 0.05, but the trend of cytokine synthesis remained the same, both before and after enzymatic treatment or saponification. This study suggests that these polysaccharides stimulate cells in a structure-dependent manner. The rhamnogalacturonan-I (RGI fragment alone was not able to induce the proliferation of PBMC.

  11. Extracellular signal-regulated kinases 1/2 and Akt contribute to triclosan-stimulated proliferation of JB6 Cl 41-5a cells.

    Science.gov (United States)

    Wu, Yuanfeng; Beland, Frederick A; Chen, Si; Fang, Jia-Long

    2015-08-01

    Triclosan is a broad spectrum anti-bacterial agent widely used in many personal care products, household items, medical devices, and clinical settings. Human exposure to triclosan is mainly through oral and dermal routes. In previous studies, we found that sub-chronic dermal exposure of B6C3F1 mice to triclosan induced epidermal hyperplasia and focal necrosis; however, the mechanisms for these responses remain elusive. In this study, using mouse epidermis-derived JB6 Cl 41-5a cells, we found that triclosan stimulated cell growth in a concentration- and time-dependent manner. Enhanced cell proliferation was demonstrated by a substantial increase in the percentage of BrdU-positive cells, an elevation in the protein levels of cyclin D1 and cyclin A, and a reduction in the protein level of p27(Kip1). Western blotting analysis revealed that triclosan induced the activation of extracellular signal-regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinases (JNK), p38, and Akt. Pre-treatment of the cells with PD184352, an inhibitor of the upstream kinase MEK1/2, or with wortmannin, an inhibitor of phosphoinositide 3-kinase, blocked triclosan-mediated phosphorylation of ERK1/2 and Akt, respectively, and substantially suppressed triclosan-stimulated cell proliferation, whereas the JNK inhibitor SP600125 or the p38 inhibitor SB203580 had little to no effect on triclosan-stimulated cell proliferation. The phosphorylation activation of ERK1/2 and Akt was further confirmed on the skin of mice dermally administered triclosan. These data suggest that the activation of ERK1/2 and Akt is involved in triclosan-stimulated proliferation of JB6 Cl 41-5a cells.

  12. Prostaglandin E2 inhibits platelet-derived growth factor-stimulated cell proliferation through a prostaglandin E receptor EP2 subtype in rat hepatic stellate cells.

    Science.gov (United States)

    Koide, Shigeki; Kobayashi, Yoshimasa; Oki, Yutaka; Nakamura, Hirotoshi

    2004-09-01

    Prostaglandin (PG) E2 inhibits hepatic stellate cell (HSC) mitogenesis. PGE-specific receptors are divided into four subtypes that are coupled either to Ca2+ mobilization (EP1 and EP3) or to the stimulation of adenyl cyclase (EP2 and EP4). The aims of the current study were to identify PGE receptor subtypes in cultured rat HSC and to examine which PGE receptor subtype(s) mediates the inhibitory effect of PGE2 on platelet-derived growth factor (PDGF)-stimulated proliferation. Reverse transcription-polymerase chain reaction analysis was performed to detect PGE receptor subtype mRNA expression. Cell proliferation was determined by measuring [3H]thymidine incorporation, and intracellular cyclic AMP was measured by radioimmunoassay. Cultured rat HSC expressed mRNAs for all four subtypes of PGE receptor. PGE2- and EP2-selective agonist produced dose-dependent inhibitory effects on PDGF-stimulated proliferation. Neither EP1-, EP3-, nor EP4-selective agonists showed any inhibitory effect. An adenylate cyclase inhibitor strongly blunted the inhibition of DNA synthesis elicited by PGE2 and the EP2 agonist. The EP2 agonist generated higher and more prolonged increases in intracellular cyclic AMP than the EP4 agonist. Activation of the PGE EP2 receptor has an antiproliferative effect in HSC that may be mediated by cyclic AMP-related signal transduction pathways.

  13. Giardia duodenalis stimulates partial maturation of bovine dendritic cells associated with altered cytokine secretion and induction of T-cell proliferation.

    Science.gov (United States)

    Grit, G H; Devriendt, B; Van Coppernolle, S; Geurden, T; Hope, J; Vercruysse, J; Cox, E; Geldhof, P; Claerebout, E

    2014-04-01

    Giardia duodenalis is an important intestinal parasite in animals and humans. The role of dendritic cells (DC) in the initiation of the immune response against G. duodenalis is poorly documented. The aim of this study was to test the hypothesis that G. duodenalis interferes with bovine DC function. Therefore, the effect of trophozoites and excretion/secretion products on bovine monocyte-derived dendritic cells (MoDC) was investigated. We assessed MoDC maturation and cytokine production of G. duodenalis-stimulated MoDC and the ability of these MoDC to take up antigen and induce lymphocyte proliferation. Little or no upregulation of maturation markers CD40 and CD80 was measured, but MHCII expression was increased after stimulation with low parasite concentrations. A dose-dependent decrease in ovalbumin uptake was observed in G. duodenalis-stimulated MoDC. In addition, stimulated MoDC induced proliferation of CD3(-) , γδ-T-cells and TCRαβ(+) CD4(+) and CD8(+) T-cells. Increased transcription of TGF-β was shown in CD4(+) T cells, and increased TNF-α, TGF-β, IL-10 and IL-4 were seen in γδ-T-cells. We found no evidence that G. duodenalis has a regulatory or inhibitory effect on bovine MoDC. MoDC stimulated with G. duodenalis are functionally active and able to induce proliferation of T cells that produce both pro- and anti-inflammatory cytokines.

  14. Remifentanil protects human keratinocytes against hypoxia-reoxygenation injury through activation of autophagy.

    Science.gov (United States)

    Kwon, Jae-Young; Park, Bong-Soo; Kim, Yong-Ho; Kim, Yong-Deok; Kim, Cheul-Hong; Yoon, Ji-Young; Yoon, Ji-Uk

    2015-01-01

    The proliferation, differentiation, and migration of keratinocytes are essential in the early stages of wound healing. Hypoxia-Reoxygenation (H/R) injury to keratinocytes can occur in various stressful environments such as surgery, trauma, and various forms of ulcers. The effects of remifentanil on human keratinocytes under hypoxia-reoxygenation have not been fully studied. Therefore, we investigated the effects of remifentanil on the proliferation, apoptosis, and autophagic activation of human keratinocytes during hypoxic-reoxygenation. Human keratinocytes were cultured under 1% oxygen tension for 24 h. The cells were then treated with various concentrations of remifentanil (0.01, 0.1, 0.5, and 1 ng/mL) for 2 h. Thereafter, the cells were reoxygenated for 12 h at 37°C. We measured cell viability via MTT assay. Using quantitative real-time PCR and western blot analysis, we measured the expression levels of proteins associated with apoptosis and autophagy. Quantification of apoptotic cells was performed using flow cytometer analysis and autophagic vacuoles were observed under a fluorescence microscope. Remifentanil treatment brought about an increase in the proliferation of human keratinocytes damaged by hypoxia-reoxygenation and decreased the apoptotic cell death, enhancing autophagic activity. However, the autophagy pathway inhibitor 3-MA inhibited the protective effect of remifentanil in hypoxia-reoxygenation injury. In conclusion, the current study demonstrated that remifentanil treatment stimulated autophagy and reduced apoptotic cell death in a hypoxia-reoxygenation model of human keratinocytes. Our results provide additional insights into the relationship between apoptosis and autophagy.

  15. Remifentanil protects human keratinocytes against hypoxia-reoxygenation injury through activation of autophagy.

    Directory of Open Access Journals (Sweden)

    Jae-Young Kwon

    Full Text Available The proliferation, differentiation, and migration of keratinocytes are essential in the early stages of wound healing. Hypoxia-Reoxygenation (H/R injury to keratinocytes can occur in various stressful environments such as surgery, trauma, and various forms of ulcers. The effects of remifentanil on human keratinocytes under hypoxia-reoxygenation have not been fully studied. Therefore, we investigated the effects of remifentanil on the proliferation, apoptosis, and autophagic activation of human keratinocytes during hypoxic-reoxygenation. Human keratinocytes were cultured under 1% oxygen tension for 24 h. The cells were then treated with various concentrations of remifentanil (0.01, 0.1, 0.5, and 1 ng/mL for 2 h. Thereafter, the cells were reoxygenated for 12 h at 37°C. We measured cell viability via MTT assay. Using quantitative real-time PCR and western blot analysis, we measured the expression levels of proteins associated with apoptosis and autophagy. Quantification of apoptotic cells was performed using flow cytometer analysis and autophagic vacuoles were observed under a fluorescence microscope. Remifentanil treatment brought about an increase in the proliferation of human keratinocytes damaged by hypoxia-reoxygenation and decreased the apoptotic cell death, enhancing autophagic activity. However, the autophagy pathway inhibitor 3-MA inhibited the protective effect of remifentanil in hypoxia-reoxygenation injury. In conclusion, the current study demonstrated that remifentanil treatment stimulated autophagy and reduced apoptotic cell death in a hypoxia-reoxygenation model of human keratinocytes. Our results provide additional insights into the relationship between apoptosis and autophagy.

  16. Targeting mitochondria by α-tocopheryl succinate overcomes hypoxia-mediated tumor cell resistance to treatment.

    Science.gov (United States)

    Kulikov, Andrey V; Vdovin, Alexander S; Zhivotovsky, Boris; Gogvadze, Vladimir

    2014-06-01

    Rapidly proliferating tumor cells easily become hypoxic. This results in acquired stability towards treatment with anticancer drugs. Here, we show that cells grown at 0.1 % oxygen are more resistant towards treatment with the conventionally used anticancer drugs doxorubicin and cisplatin. The stimulation of apoptosis, as assessed by the number of cells in the SubG1 fraction of the cell cycle, release of cytochrome c into the cytosol, activation of caspase-3, and cleavage of PARP, was markedly suppressed under low oxygen content or when hypoxia was mimicked by deferoxamine. Hypoxia or deferoxamine treatment was accompanied by stabilization of the hypoxia-inducible factor (HIF-1). The downregulation of HIF-1 using siRNA technique restored cell sensitivity to treatment under hypoxic conditions to the levels detected under normoxic conditions. In contrast to cisplatin or doxorubicin, α-tocopheryl succinate (α-TOS), a compound that targets mitochondria, stimulated cell death irrespective of the oxygen concentration. Moreover, under hypoxic condition cell death induced by α-TOS was even enhanced. Thus, α-TOS can successfully overcome resistance to treatment caused by hypoxia, which makes α-TOS an attractive candidate for antitumor therapy via mitochondrial targeting.

  17. Silencing of reversion-inducing cysteine-rich protein with Kazal motifs stimulates hyperplastic phenotypes through activation of epidermal growth factor receptor and hypoxia-inducible factor-2α.

    Directory of Open Access Journals (Sweden)

    You Mie Lee

    Full Text Available Reversion-inducing cysteine-rich protein with Kazal motifs (RECK, a tumor suppressor is down-regulated by the oncogenic signals and hypoxia, but the biological function of RECK in early tumorigenic hyperplastic phenotypes is largely unknown. Knockdown of RECK by small interfering RNA (siRECK or hypoxia significantly promoted cell proliferation in various normal epithelial cells. Hypoxia as well as knockdown of RECK by siRNA increased the cell cycle progression, the levels of cyclin D1 and c-Myc, and the phosphorylation of Rb protein (p-pRb, but decreased the expression of p21(cip1, p27(kip1, and p16(ink4A. HIF-2α was upregulated by knockdown of RECK, indicating HIF-2α is a downstream target of RECK. As knockdown of RECK induced the activation of epidermal growth factor receptor (EGFR and treatment of an EGFR kinase inhibitor, gefitinib, suppressed HIF-2α expression induced by the silencing of RECK, we can suggest that the RECK silenicng-EGFR-HIF-2α axis might be a key molecular mechanism to induce hyperplastic phenotype of epithelial cells. It was also found that shRNA of RECK induced larger and more numerous colonies than control cells in an anchorage-independent colony formation assay. Using a xenograft assay, epithelial cells with stably transfected with shRNA of RECK formed a solid mass earlier and larger than those with control cells in nude mice. In conclusion, the suppression of RECK may promote the development of early tumorigenic hyperplastic characteristics in hypoxic stress.

  18. GDNF stimulates the proliferation of cultured mouse immature Sertoli cells via its receptor subunit NCAM and ERK1/2 signaling pathway

    Directory of Open Access Journals (Sweden)

    Yang Yongguang

    2010-10-01

    Full Text Available Abstract Background The proliferation and final density of Sertoli cells in the testis are regulated by hormones and local factors. Glial cell line-derived neurotrophic factor (GDNF, a distantly related member of the transforming growth factor-β superfamily, and its receptor subunits GDNF family receptor alpha 1 (GFRα1, RET tyrosine kinase, and neural cell adhesion molecule (NCAM have been reported to be expressed in the testis and involved in the regulation of proliferation of immature Sertoli cells (ISCs. However, the expression patterns of these receptor subunits and the downstream signaling pathways have not been addressed in ISCs. Results In the present study, we have reported that the proliferation of cultured ISCs was significantly enhanced by GDNF. The receptor subunits GFRα1 and NCAM but not RET were expressed in ISCs, and the stimulatory effect of GDNF on the proliferation of ISCs was significantly reduced by anti-NCAM antibody blocking or siRNA that specifically targets NCAM mRNA. Additionally, the ERK1/2 inhibitor, PD98059, completely abolished the mitogenic effect of GDNF on ISCs. Conclusions GDNF stimulates the proliferation of ISCs via its receptor subunit NCAM and the consequent activation of the ERK1/2 signaling pathway.

  19. A peptide from Porphyra yezoensis stimulates the proliferation of IEC-6 cells by activating the insulin-like growth factor I receptor signaling pathway.

    Science.gov (United States)

    Lee, Min-Kyeong; Kim, In-Hye; Choi, Youn-Hee; Nam, Taek-Jeong

    2015-02-01

    Porphyra yezoensis (P. yezoensis) is the most noteworthy red alga and is mainly consumed in China, Japan and Korea. In the present study, the effects of a P. yezoensis peptide (PY‑PE) on cell proliferation and the associated signaling pathways were examined in IEC‑6 rat intestinal epithelial cells. First, the MTS assay showed that PY‑PE induced cell proliferation in a dose‑dependent manner. Subsequently, the mechanism behind the proliferative activity induced by PY‑PE was determined. The insulin‑like growth factor‑I receptor (IGF‑IR) signaling pathway was the main focus as it plays an important role in the regulation of cell growth and proliferation. PY‑PE increased the protein and mRNA expression of IGF‑IR, insulin receptor substrate‑1, Shc and PY‑99. In addition, PY‑PE stimulated extracellular signal‑regulated kinase phosphorylation and phosphatidylinositol 3‑kinase/Akt activation but inhibited p38 and c‑Jun N‑terminal kinase phosphorylation. Furthermore, PY‑PE treatment increased protein and mRNA expression levels of activator protein‑1, which regulates cell proliferation and survival, in the nuclear fraction. These results have significant implications for understanding the role of cell proliferation signaling pathways in intestinal epithelial cells.

  20. Luminal and basal-like breast cancer cells show increased migration induced by hypoxia, mediated by an autocrine mechanism

    Directory of Open Access Journals (Sweden)

    Zänker Kurt S

    2011-05-01

    Full Text Available Abstract Background Some breast cancer patients receiving anti-angiogenic treatment show increased metastases, possibly as a result of induced hypoxia. The effect of hypoxia on tumor cell migration was assessed in selected luminal, post-EMT and basal-like breast carcinoma cell lines. Methods Migration was assessed in luminal (MCF-7, post-EMT (MDA-MB-231, MDA-MB-435S, and basal-like (MDA-MB-468 human breast carcinoma cell lines under normal and oxygen-deprived conditions, using a collagen-based assay. Cell proliferation was determined, secreted cytokine and chemokine levels were measured using flow-cytometry and a bead-based immunoassay, and the hypoxic genes HIF-1α and CA IX were assessed using PCR. The functional effect of tumor-cell conditioned medium on the migration of neutrophil granulocytes (NG was tested. Results Hypoxia caused increased migratory activity but not proliferation in all tumor cell lines, involving the release and autocrine action of soluble mediators. Conditioned medium (CM from hypoxic cells induced migration in normoxic cells. Hypoxia changed the profile of released inflammatory mediators according to cell type. Interleukin-8 was produced only by post-EMT and basal-like cell lines, regardless of hypoxia. MCP-1 was produced by MDA-MB-435 and -468 cells, whereas IL-6 was present only in MDA-MB-231. IL-2, TNF-α, and NGF production was stimulated by hypoxia in MCF-7 cells. CM from normoxic and hypoxic MDA-MB-231 and MDA-MB-435S cells and hypoxic MCF-7 cells, but not MDA-MB-468, induced NG migration. Conclusions Hypoxia increases migration by the autocrine action of released signal substances in selected luminal and basal-like breast carcinoma cell lines which might explain why anti-angiogenic treatment can worsen clinical outcome in some patients.

  1. Metallic gold treatment reduces proliferation of inflammatory cells, increases expression of VEGF and FGF, and stimulates cell proliferation in the subventricular zone following experimental traumatic brain injury

    DEFF Research Database (Denmark)

    Pedersen, Mie Østergaard; Larsen, Agnete; Pedersen, Dan Sonne

    2009-01-01

    -treated mice subjected to cryo-lesion served as controls. The effects of gold-treatment were investigated by examining gold-induced growth factor expression (VEGF and FGF) in the first two weeks after the insult, and the extent of the neurostimulatory effect of gold was explored by comparing cell proliferation...... in the subventricular zone as judged by immunohistochemical staining for CDC47. Vimentin staining revealed a decrease in activated microglia and a transient astrogliosis in response to the gold liberation. Moreover, gold ions significantly increase the expression of VEGF and FGF following trauma and a significant...

  2. The stimulation of proliferation and differentiation of periodontal ligament cells by the ionic products from Ca7Si2P2O16 bioceramics.

    Science.gov (United States)

    Zhou, Yinghong; Wu, Chengtie; Xiao, Yin

    2012-07-01

    The ultimate goal of periodontal tissue engineering is to produce predictable regeneration of alveolar bone, root cementum, and periodontal ligament, which are lost as a result of periodontal diseases. To achieve this goal, it is of great importance to develop novel bioactive materials which could stimulate the proliferation, differentiation and osteogenic/cementogenic gene expression of periodontal ligament cells (PDLCs) for periodontal regeneration. In this study, we synthesized novel Ca(7)Si(2)P(2)O(16) ceramic powders for the first time by the sol-gel method and investigated the biological performance of PDLCs after exposure to different concentrations of Ca(7)Si(2)P(2)O(16) extracts. The original extracts were prepared at 200 mg ml(-1) and further diluted with serum-free cell culture medium to obtain a series of diluted extracts (100, 50, 25, 12.5 and 6.25 mg ml(-1)). Proliferation, alkaline phosphatase (ALP) activity, Ca deposition, and osteogenesis/cementogenesis-related gene expression (ALP, Col I, Runx2 and CEMP1) were assayed for PDLCs on days 7 and 14. The results showed that the ionic products from Ca(7)Si(2)P(2)O(16) powders significantly stimulated the proliferation, ALP activity, Ca deposition and osteogenesis/cementogenesis-related gene expression of PDLCs. In addition, it was found that Ca(7)Si(2)P(2)O(16) powders had excellent apatite-mineralization ability in simulated body fluids. This study demonstrated that Ca(7)Si(2)P(2)O(16) powders with such a specific composition possess the ability to stimulate the PDLC proliferation and osteoblast/cemenoblast-like cell differentiation, indicating that they are a promising bioactive material for periodontal tissue regeneration application.

  3. Intermittent hypoxia and neurorehabilitation.

    Science.gov (United States)

    Gonzalez-Rothi, Elisa J; Lee, Kun-Ze; Dale, Erica A; Reier, Paul J; Mitchell, Gordon S; Fuller, David D

    2015-12-15

    In recent years, it has become clear that brief, repeated presentations of hypoxia [i.e., acute intermittent hypoxia (AIH)] can boost the efficacy of more traditional therapeutic strategies in certain cases of neurologic dysfunction. This hypothesis derives from a series of studies in animal models and human subjects performed over the past 35 yr. In 1980, Millhorn et al. (Millhorn DE, Eldridge FL, Waldrop TG. Respir Physiol 41: 87-103, 1980) showed that electrical stimulation of carotid chemoafferent neurons produced a persistent, serotonin-dependent increase in phrenic motor output that outlasts the stimulus for more than 90 min (i.e., a "respiratory memory"). AIH elicits similar phrenic "long-term facilitation" (LTF) by a mechanism that requires cervical spinal serotonin receptor activation and de novo protein synthesis. From 2003 to present, a series of studies demonstrated that AIH can induce neuroplasticity in the injured spinal cord, causing functional recovery of breathing capacity after cervical spinal injury. Subsequently, it was demonstrated that repeated AIH (rAIH) can induce recovery of limb function, and the functional benefits of rAIH are greatest when paired with task-specific training. Since uncontrolled and/or prolonged intermittent hypoxia can elicit pathophysiology, a challenge of intermittent hypoxia research is to ensure that therapeutic protocols are well below the threshold for pathogenesis. This is possible since many low dose rAIH protocols have induced functional benefits without evidence of pathology. We propose that carefully controlled rAIH is a safe and noninvasive modality that can be paired with other neurorehabilitative strategies including traditional activity-based physical therapy or cell-based therapies such as intraspinal transplantation of neural progenitors.

  4. Proliferation and Cytokine Production of Human Mesangial Cells Stimulated by Secretory IgA Isolated from Patients with IgA Nephropathy

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    Yan Liang

    2015-07-01

    Full Text Available Background/Aims: IgA nephropathy (IgAN is the most common form of primary glomerulonephritis, and often aggravates by mucosal infection. Secretory IgA (SIgA is the dominant immunoglobulin in mucosal immunity, and is deposited in the mesangium in IgAN. The biological effects of SIgA on mesangial cells are poorly understood. Methods: Deposition of SIgA in frozen renal sections from IgAN patients was detected and the association between deposition of SIgA and patients characteristics was analyzed. The biological effects of SIgA and polymeric IgA (pIgA on human renal mesangial cells were compared. We also studied the molecular mechanism of microRNA regulating the inflammatory effects of SIgA on mesangial cells. Results: Fifty-five of 176 patients had SIgA deposition with higher incidence of infection history and hematuria, lower serum cystatin C, β2 microglobulin, blood urea nitrogen and T-grade in the Oxford classification, compared with patients without SIgA deposition. SIgA stimulated mesangial cells at a higher ratio of proliferation and higher production of interleukin (IL-6, IL-8, monocyte chemotactic protein 1, transforming growth factor-β1 and fibronectin, compared with SIgA from healthy volunteers. The proliferation and cytokines production in mesangial cells stimulated by SIgA were significantly lower than that stimulated by pIgA. miR-16 targeted the 3′-untranslated region of IL-6 and suppressed its translation in mesangial cells induced by SIgA. Conclusions: The biological effects of SIgA on mesangial cells differ from those of pIgA. SIgA stimulates mesangial cell proliferation and production of proinflammatory cytokines. IL-6 production is regulated by miR-16 in mesangial cells.

  5. Acemannan stimulates gingival fibroblast proliferation; expressions of keratinocyte growth factor-1, vascular endothelial growth factor, and type I collagen; and wound healing.

    Science.gov (United States)

    Jettanacheawchankit, Suwimon; Sasithanasate, Siriruk; Sangvanich, Polkit; Banlunara, Wijit; Thunyakitpisal, Pasutha

    2009-04-01

    Aloe vera has long been used as a traditional medicine for inducing wound healing. Gingival fibroblasts (GFs) play an important role in oral wound healing. In this study, we investigated the effects of acemannan, a polysaccharide extracted from Aloe vera gel, on GF proliferation; keratinocyte growth factor-1 (KGF-1), vascular endothelial growth factor (VEGF), and type I collagen production; and oral wound healing in rats. [(3)H]-Thymidine incorporation assay and ELISA were used. Punch biopsy wounds were created at the hard palate of male Sprague Dawley rats. All treatments (normal saline; 0.1% triamcinolone acetonide; plain 1% Carbopol; and Carbopol containing 0.5%, 1%, and 2% acemannan (w/w)) were applied daily. Wounded areas and histological features were observed at day 7 after treatment. From our studies, acemannan at concentrations of 2, 4, 8, and 16 mg/ml significantly induced cell proliferation (P<0.05). Acemannan concentrations between 2 - 16 mg/ml significantly stimulated KGF-1, VEGF, and type I collagen expressions (P<0.05). Wound healing of animals receiving Carbopol containing 0.5% acemannan (w/w) was significantly better than that of the other groups (P<0.05). These findings suggest that acemannan plays a significant role in the oral wound healing process via the induction of fibroblast proliferation and stimulation of KGF-1, VEGF, and type I collagen expressions.

  6. FGFR1 signaling stimulates proliferation of human mesenchymal stem cells by inhibiting the cyclin-dependent kinase inhibitors p21(Waf1) and p27(Kip1).

    Science.gov (United States)

    Dombrowski, Christian; Helledie, Torben; Ling, Ling; Grünert, Martin; Canning, Claire A; Jones, C Michael; Hui, James H; Nurcombe, Victor; van Wijnen, Andre J; Cool, Simon M

    2013-12-01

    Signaling through fibroblast growth factor receptor one (FGFR1) is a known inducer of proliferation in both embryonic and human adult mesenchymal stem cells (hMSCs) and positively regulates maintenance of stem cell viability. Leveraging the mitogenic potential of FGF2/FGFR1 signaling in stem cells for therapeutic applications necessitates a mechanistic understanding of how this receptor stimulates cell cycle progression. Using small interfering RNA (siRNA) depletion, antibody-inhibition, and small molecule inhibition, we establish that FGFR1 activity is rate limiting for self-renewal of hMSCs. We show that FGFR1 promotes stem cell proliferation through multiple mechanisms that unite to antagonize cyclin-dependent kinase (CDK) inhibitors. FGFR1 not only stimulates c-Myc to suppress transcription of the CDK inhibitors p21(Waf1) and p27(Kip1), thus promoting cell cycle progression but also increases the activity of protein kinase B (AKT) and the level of S-phase kinase-associated protein 2 (Skp2), resulting in the nuclear exclusion and reduction of p21(Waf1). The in vivo importance of FGFR1 signaling for the control of proliferation in mesenchymal progenitor populations is underscored by defects in ventral mesoderm formation during development upon inhibition of its signaling. Collectively, these studies demonstrate that FGFR1 signaling mediates the continuation of MSC growth and establishes a receptor target for enhancing the expansion of mesenchymal progenitors while maintaining their multilineage potential.

  7. First-line treatment with bortezomib rapidly stimulates both osteoblast activity and bone matrix deposition in patients with multiple myeloma, and stimulates osteoblast proliferation and differentiation in vitro

    DEFF Research Database (Denmark)

    Lund, Thomas; Søe, Kent; Abildgaard, Niels

    2010-01-01

    OBJECTIVES: The aim of the study was to investigate the effect of bortezomib on osteoblast proliferation and differentiation, as well as on bone matrix deposition for the first time in bisphosphonate-naïve, previously untreated patients with myeloma. METHODS: Twenty newly diagnosed patients recei...

  8. Platelet-rich plasma stimulates human dermal fibroblast proliferation via a Ras-dependent extracellular signal-regulated kinase 1/2 pathway.

    Science.gov (United States)

    Hara, Tomoya; Kakudo, Natsuko; Morimoto, Naoki; Ogawa, Takeshi; Lai, Fangyuan; Kusumoto, Kenji

    2016-12-01

    Platelet-rich plasma (PRP) contains a high concentration of several growth factors and contributes to soft-tissue engineering and wound healing. However, the effect of PRP on human dermal fibroblast proliferation and responses is unknown. This was investigated in the present study using PRP prepared from the whole human blood using the double-spin method. Human dermal fibroblast cultures were established from skin samples collected during plastic surgery. Platelet concentration and growth factor levels in PRP were estimated, and a cell proliferation assay was carried out after PRP treatment. The role of Ras-dependent extracellular signal-regulated kinase (ERK)1/2 in the effects of PRP was investigated in human dermal fibroblasts by suppressing ERK1/2 expression with an inhibitor or by short interfering (si)RNA-mediated knockdown, and assessing ERK1/2 phosphorylation by western blotting as well as proliferation in PRP-treated cells. We found that PRP stimulated human dermal fibroblast proliferation, which was suppressed by ERK1/2 inhibitor treatment (P < 0.01). ERK1/2 phosphorylation was increased in the presence of PRP, while siRNA-mediated knockdown of ERK1/2 blocked cell proliferation normally induced by PRP treatment (P < 0.01). These results demonstrate that PRP induces human dermal fibroblast proliferation via activation of ERK1/2 signaling. Our findings provide a basis for the development of agents that can promote wound healing and can be applied to soft-tissue engineering.

  9. Lectin-like oxidized LDL receptor-1 expresses in mouse bone marrow-derived mesenchymal stem cells and stimulates their proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fenxi [Department of Anatomy, Sanquan College, Xinxiang Medical University, Xinxiang 453003 (China); Stem Cell and Biotheraphy Technology Research Center, College of Lifescience and Technology, Xinxiang Medical University, Xinxiang 453003 (China); Wang, Congrui [Stem Cell and Biotheraphy Technology Research Center, College of Lifescience and Technology, Xinxiang Medical University, Xinxiang 453003 (China); Jing, Suhua [ICU Center, The Third Hospital of Xinxiang Medical University, Xinxiang 453003 (China); Ren, Tongming [Department of Anatomy, Sanquan College, Xinxiang Medical University, Xinxiang 453003 (China); Li, Yonghai; Cao, Yulin [Stem Cell and Biotheraphy Technology Research Center, College of Lifescience and Technology, Xinxiang Medical University, Xinxiang 453003 (China); Lin, Juntang, E-mail: juntang.lin@googlemail.com [Stem Cell and Biotheraphy Technology Research Center, College of Lifescience and Technology, Xinxiang Medical University, Xinxiang 453003 (China)

    2013-04-15

    The bone marrow-derived mesenchymal stem cells (bmMSCs) have been widely used in cell transplant therapy, and the proliferative ability of bmMSCs is one of the determinants of the therapy efficiency. Lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) as a transmembrane protein is responsible for binding, internalizing and degrading oxidized low density lipoprotein (ox-LDL). It has been identified that LOX-1 is expressed in endothelial cells, vascular smooth muscle cells, cardiomyocytes, fibroblasts and monocytes. In these cells, low concentration of ox-LDL (<40 μg/mL) stimulates their proliferation via LOX-1 activation. However, it is poor understood that whether LOX-1 is expressed in bmMSCs and which role it plays. In this study, we investigated the status of LOX-1 expression in bmMSCs and its function on bmMSC proliferation. Our results showed that primary bmMSCs exhibiting a typical fibroblast-like morphology are positive for CD44 and CD90, but negative for CD34 and CD45. LOX-1 in both mRNA and protein levels is highly expressed in bmMSCs. Meanwhile, bmMSCs exhibit a strong potential to take up ox-LDL. Moreover, LOX-1 expression in bmMSCs is upregulated by ox-LDL with a dose- and time-dependent manner. Presence of ox-LDL also enhances the proliferation of bmMSCs. Knockdown of LOX-1 expression significantly inhibits ox-LDL-induced bmMSC proliferation. These findings indicate that LOX-1 plays a role in bmMSC proliferation. - Highlights: ► LOX-1 expresses in bmMSCs and mediates uptake of ox-LDL. ► Ox-LDL stimulates upregulation of LOX-1 in bmMSCs. ► Ox-LDL promotes bmMSC proliferation and expression of Mdm2, phosphor-Akt, phosphor-ERK1/2 and phosphor-NF-κB. ► LOX-1 siRNA inhibits ox-LDL-induced bmMSC proliferation and expression cell survival signals.

  10. Co-culture with human synovium-derived mesenchymal stem cells inhibits inflammatory activity and increases cell proliferation of sodium nitroprusside-stimulated chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jae-Sung; Jung, Yeon-Hwa; Cho, Mi-Young; Yeo, Jee Eun; Choi, Yun-Jin; Kim, Yong Il; Koh, Yong-Gon, E-mail: yonseranglab@daum.net

    2014-05-16

    Highlights: • Co-culture of hSDMSCs with SNP-stimulated chondrocytes improves anti-inflammation. • Co-culture system produces IGF-1. • Co-culture system suppresses inflammatory genes expression. • Co-culture system improves cell proliferation. • Exogenous IGF-1 inhibits inflammatory activity in SNP-stimulated chondrocytes. - Abstract: Rheumatoid arthritis (RA) and osteoarthritis (OA) are primarily chronic inflammatory diseases. Mesenchymal stem cells (MSCs) have the ability to differentiate into cells of the mesodermal lineage, and to regulate immunomodulatory activity. Specifically, MSCs have been shown to secrete insulin-like growth factor 1 (IGF-1). The purpose of the present study was to examine the inhibitory effects on inflammatory activity from a co-culture of human synovium-derived mesenchymal stem cells (hSDMSCs) and sodium nitroprusside (SNP)-stimulated chondrocytes. First, chondrocytes were treated with SNP to generate an in vitro model of RA or OA. Next, the co-culture of hSDMSCs with SNP-stimulated chondrocytes reduced inflammatory cytokine secretion, inhibited expression of inflammation activity-related genes, generated IGF-1 secretion, and increased the chondrocyte proliferation rate. To evaluate the effect of IGF-1 on inhibition of inflammation, chondrocytes pre-treated with IGF-1 were treated with SNP, and then the production of inflammatory cytokines was analyzed. Treatment with IGF-1 was shown to significantly reduce inflammatory cytokine secretion in SNP-stimulated chondrocytes. Our results suggest that hSDMSCs offer a new strategy to promote cell-based cartilage regeneration in RA or OA.

  11. Fetal neural tube stem cells from Pax3 mutant mice proliferate, differentiate, and form synaptic connections when stimulated with folic acid.

    Science.gov (United States)

    Ichi, Shunsuke; Nakazaki, Hiromichi; Boshnjaku, Vanda; Singh, Ravneet Monny; Mania-Farnell, Barbara; Xi, Guifa; McLone, David G; Tomita, Tadanori; Mayanil, Chandra Shekhar K

    2012-01-20

    Although maternal intake of folic acid (FA) prevents neural tube defects in 70% of the population, the exact mechanism of prevention has not been elucidated. We hypothesized that FA affects neural stem cell (NSC) proliferation and differentiation. This hypothesis was examined in a folate-responsive spina bifida mouse model, Splotch (Sp(-/-)), which has a homozygous loss-of-function mutation in the Pax3 gene. Neurospheres were generated with NSCs from the lower lumbar neural tube of E10.5 wild-type (WT) and Sp(-/-) embryos, in the presence and absence of FA. In the absence of FA, the number of neurospheres generated from Sp(-/-) embryos compared with WT was minimal (Pcell differentiation, FA-stimulated Sp(-/-) neurospheres were allowed to differentiate in the continued presence or absence of FA. Neurospheres from both conditions expressed multi-potent stem cell characteristics and the same differentiation potential as WT. Further, multiple neurospheres from both WT and FA-stimulated Sp(-/-) cell cultures formed extensive synaptic connections. On the whole, FA-mediated rescue of neural tube defects in Sp(-/-) embryos promotes NSC proliferation at an early embryonic stage. FA-stimulated Sp(-/-) neurospheres differentiate and form synaptic connections, comparable to WT.

  12. Ginsenoside Rg1 inhibits proliferation of vascular smooth muscle cells stimulated by tumor necrosis factor-α

    Institute of Scientific and Technical Information of China (English)

    Zeng-chun MA; Yue GAO; Yu-guang WANG; Hong-ling TAN; Cheng-rong XIAO; Sheng-qi WANG

    2006-01-01

    Aim: To investigate the proliferation of vascular smooth muscle cells (VSMC) affected by ginsenoside Rg1 and further explore the molecular mechanism of ginsenoside Rg1 using proteomics. Methods: The proliferation of VSMC was measured by MTS assay kit and flow cytometry. Proteomic alterations were analyzed using two-dimensional electrophoresis and peptide mass fingerprinting. Differential proteins found in proteomics were confirmed by RT-PCR. Results: The proliferation of VSMC was enhanced significantly after tumor necrosis factor-α (TNF-α) treatment, and ginsenoside Rg1 treatment inhibited proliferation in a dose-dependent manner. Proteomic analysis showed 24 protein spots were changed, including 17 spots that were increased and 7 spots that were decreased. Ginsenoside Rg1 could restore the expression levels of these proteins, at least partly, to basic levels of untreated cells. The expression of G-protein coupled receptor kinase, protein kinase C (PKC)-ζ, N-ras protein were decreased, while cycle related protein p21 was increased by ginsenoside Rg1 in TNF-α treated VSMC. Conclusion: PKC-ζ, and p21 pathway might be the mechanism for inhibitory effects of ginsenoside Rg1 on proliferation of VSMC.

  13. Monocyte-derived dendritic cells enhance cell proliferation and porcine circovirus type 2 replication in concanavalin A-stimulated swine peripheral blood lymphocytes in vitro.

    Science.gov (United States)

    Lin, Chun-Ming; Jeng, Chian-Ren; Hsiao, Shih-Hsuan; Lee, Yao; Tsai, Yi-Chieh; Chia, Mi-Yuan; Pang, Victor Fei

    2012-01-15

    Dendritic cells (DCs) are professional antigen presenting cells cooperating with other immune cells for the activation of innate and adaptive immune responses. The objective of the present study was to investigate the replication activity of porcine circovirus type 2 (PCV2) in DCs and/or lymphocytes during their cross talk and its possible mechanism. Two models were set, herein. Swine blood monocyte (Mo)-derived DCs (MoDCs) or peripheral blood lymphocytes (PBLs) were inoculated with PCV2 prior to their co-cultivation. Bacterial lipopolysaccharide (LPS) and concanavalin A (Con A) were used to stimulate MoDCs and PBLs, respectively. During 6 days of cultivation, a high PCV2 antigen-containing rate without detectable intranuclear signals and a slight but significant increase in the copy number of PCV2 genome were detected in PCV2-inoculated MoDCs. The presence of LPS alone or PCV2-free PBLs, however, had no effect on the location of PCV2 antigens or copy number of PCV2 genome in PCV2-inoculated MoDCs. On the contrary, active PCV2 replication occurred in Con A-stimulated PCV2-inoculated PBLs. When compared with blood Mos, MoDCs induced significantly higher cell proliferation and intensified PCV2 replication in Con A-stimulated PCV2-inoculated PBLs, for which direct contact between MoDCs and lymphocytes was required. Among the cytokines secreted by Con A-activated PBLs, interleukin (IL)-2, but not IL-4 or interferon-γ, could induce cell proliferation and PCV2 replication in PCV2-inoculated PBLs. The findings suggest that although MoDCs support only limited PCV2 replication in themselves, their accessory cell function is required for cell proliferation and PCV2 replication in PCV2-infected lymphocytes.

  14. A traditional Chinese medicine formula extracts stimulate proliferation and inhibit mineralization of human mesenchymal stem cells in vitro

    DEFF Research Database (Denmark)

    Chen, Muwan; Feng, Wenzhou; Cao, Hui

    2009-01-01

    AIM OF THE STUDY: To investigate the effects of a traditional Chinese medicine (TCM) formula extract, named as ZD-I, on the proliferation and osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro. MATERIALS AND METHODS: When hMSCs cultivated in the basal medium with ZD-I, cell...... viability was assessed by MTT assay and cellular proliferation was assessed by SYBR green I assay. The effects of ZD-I on osteogenic differentiation of hMSCs were assessed by alkaline phosphatase (ALP) activity, mineralization assay and real-time RT-PCR. RESULTS: ZD-I (0.78-100 microg/ml) was non...

  15. Triterpenoid α-amyrin stimulates proliferation of human keratinocytes but does not protect them against UVB damage

    DEFF Research Database (Denmark)

    Biskup, Edyta; Gołębiowski, Marek; Gniadecki, Robert;

    2012-01-01

    Rhaponticum carthamoides plants ("maral root") are widely used in Siberian folk medicine. The present study reports for the first time the presence of pentacyclic terpenoid, α-amyrin, in methanol extract from leaves of this plant. α-Amyrin induced proliferation of human keratinocytes (HaCaT) by a......Rhaponticum carthamoides plants ("maral root") are widely used in Siberian folk medicine. The present study reports for the first time the presence of pentacyclic terpenoid, α-amyrin, in methanol extract from leaves of this plant. α-Amyrin induced proliferation of human keratinocytes (Ha...

  16. Short-Chain Fatty Acids Stimulate Angiopoietin-Like 4 Synthesis in Human Colon Adenocarcinoma Cells by Activating Peroxisome Proliferator-Activated Receptor γ

    DEFF Research Database (Denmark)

    Alex, Sheril; Lange, Katja; Amolo, Tom

    2013-01-01

    -chain fatty acids (SCFA). SCFA induce ANGPTL4 by activating the nuclear receptor peroxisome proliferator activated receptor γ (PPARγ), as demonstrated using PPARγ antagonist, PPARγ knockdown, and transactivation assays, which show activation of PPARγ but not PPARα and PPARδ by SCFA. At concentrations required...... for PPARγ activation and ANGPTL4 induction in colon adenocarcinoma cells, SCFA do not stimulate PPARγ in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPARγ modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modeling. Consistent...... with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin induced PPAR target genes and pathways in the colon. We conclude that (i) SCFA potently stimulate ANGPTL4 synthesis in human colon adenocarcinoma cells and (ii) SCFA transactivate and bind to PPARγ. Our data...

  17. The insulin-like growth factors I and II stimulate proliferation of different types of Schwann cells

    DEFF Research Database (Denmark)

    Sondell, M; Svenningsen, Åsa Fex; Kanje, M

    1997-01-01

    A combination of immunocytochemistry for glial specific antigens and bromodeoxyuridine (BrdU) and teasing was used to identify proliferating cells in cultured rat sciatic nerve segments. The nerve segments were exposed to insulin, or the insulin-like growth factors IGF-I and IGF-II. Teasing...

  18. The effect of long-term hypoxia on tension and intracellular calcium responses following stimulation of the thromboxane A(2) receptor in the left anterior descending coronary artery of fetal sheep.

    Science.gov (United States)

    Maruko, Keiko; Stiffel, Virginia M; Gilbert, Raymond D

    2009-04-01

    The purpose of this study was to investigate the mechanisms of tension and intracellular calcium regulation following stimulation with the thromboxane A(2) receptor agonist U46619 in the left anterior descending coronary artery of fetal sheep exposed to long-term hypoxia. We hypothesized that there would be a reduction in intracellular calcium responses in long-term hypoxic left anterior descending coronary artery accompanied by an increase in calcium sensitivity of the contractile mechanism. Pregnant sheep were kept at altitude (3820 m) from day 30 of gestation until day 140. Fetal hearts from long-term hypoxic and from a control, normoxic group were obtained and the left anterior descending coronary artery of the fetus was dissected, cleaned, and mounted in a bath (Jasco) in which tension and intracellular calcium [Ca(2+)](i), using Fura-2, could be measured simultaneously following stimulation of the thromboxane A(2) receptor with U46619. The role of intracellular calcium and the Rho kinase and protein kinase C pathways in the tension responses were investigated by maintaining intracellular calcium constant or by using the Rho kinase blocker, Y27632, or the protein kinase C blocker, GF109203-X. There was no difference in the tension dose-response to U46619 between the normoxic fetal and hypoxic fetal left anterior descending, although [Ca(2+)](i) was lower in the hypoxic fetal than normoxic fetal at the highest doses. When [Ca(2+)]( i) was maintained constant at baseline levels, U46619 produced the same tension dose-response in both normoxic fetal and hypoxic fetal left anterior descending as when [Ca(2+)](i) was allowed to rise. The tension response was abolished in both groups when the Rho kinase inhibitor, Y27632, was given either during or before stimulation with U46619. The protein kinase C blocker, GF109203-X, had no effect on the tension response in either group. Long-term hypoxia did not alter the tension response to thromboxane A(2) receptor stimulation

  19. Acidosis, hypoxia and bone.

    Science.gov (United States)

    Arnett, Timothy R

    2010-11-01

    Bone homeostasis is profoundly affected by local pH and oxygen tension. It has long been recognised that the skeleton contains a large reserve of alkaline mineral (hydroxyapatite), which is ultimately available to neutralise metabolic H(+) if acid-base balance is not maintained within narrow limits. Bone cells are extremely sensitive to the direct effects of pH: acidosis inhibits mineral deposition by osteoblasts but it activates osteoclasts to resorb bone and other mineralised tissues. These reciprocal responses act to maximise the availability of OH(-) ions from hydroxyapatite in solution, where they can buffer excess H(+). The mechanisms by which bone cells sense small pH changes are likely to be complex, involving ion channels and receptors in the cell membrane, as well as direct intracellular effects. The importance of oxygen tension in the skeleton has also long been known. Recent work shows that hypoxia blocks the growth and differentiation of osteoblasts (and thus bone formation), whilst strongly stimulating osteoclast formation (and thus bone resorption). Surprisingly, the resorptive function of osteoclasts is unimpaired in hypoxia. In vivo, tissue hypoxia is usually accompanied by acidosis due to reduced vascular perfusion and increased glycolytic metabolism. Thus, disruption of the blood supply can engender a multiple negative impact on bone via the direct actions of reduced pO(2) and pH on bone cells. These observations may contribute to our understanding of the bone disturbances that occur in numerous settings, including ageing, inflammation, fractures, tumours, anaemias, kidney disease, diabetes, respiratory disease and smoking.

  20. Polysaccharides of St. John’s Wort Herb Stimulate NHDF Proliferation and NEHK Differentiation via Influence on Extracellular Structures and Signal Pathways

    Directory of Open Access Journals (Sweden)

    S. Abakuks

    2012-01-01

    Full Text Available St. John's Wort herb extracts often contain undesirable or volitional polysaccharides. As polysaccharides exhibit structure-dependent biological functions in the present study water-soluble polysaccharides were extracted from herb material, fractionated by anion exchange chromatography into four main polysaccharide fractions (denominated as Hp1, Hp2, Hp3 and Hp4 and characterized by HPAEC-PAD, CE, IR and GC-MS. Biological activity on human skin keratinocytes and fibroblasts was assessed by investigation of their effect on proliferation, metabolism, cytotoxicity, apoptosis and differentiation. The underlying mechanisms were investigated in gene expression studies. Polysaccharide fraction Hp1 was mainly composed of β-D-glucose. Hp2, Hp3 and Hp4 contained pectic structures and arabinogalactan proteins varying in composition and quantity. Polysaccharides of Hp1 induced the keratinocyte differentiation by inhibiting the gene expression of the epidermal growth factor and insulin receptor. While the collagen secretion of fibroblasts was stimulated by each polysaccharide fraction only Hp1 stimulated the synthesis. The fibroblast proliferation was reduced by Hp1 and increased by Hp4. This effect was related to the influence on genes that referred to oxidative stress, metabolism, transcription processes and extracellular proteins. In conclusion polysaccharides have been shown as biologically active ingredients of aqueous St. John's Wort extracts with a relation between their structural characteristics and function.

  1. Sarcophine-Diol, a Skin Cancer Chemopreventive Agent, Inhibits Proliferation and Stimulates Apoptosis in Mouse Melanoma B16F10 Cell Line

    Directory of Open Access Journals (Sweden)

    Hesham Fahmy

    2011-12-01

    Full Text Available Sarcodiol (SD is a semi-synthetic derivative of sarcophine, a marine natural product. In our previous work, we reported the significant chemopreventive effects of SD against non-melanoma skin cancer both in vitro and in vivo mouse models. In this investigation, we extended this work to study the effect of sarcodiol on melanoma development, the more deadly form of skin cancer, using the mouse melanoma B16F10 cell line. In this study we report that SD inhibits the de novo DNA synthesis and enhances fragmentation of DNA. We also evaluated the antitumor effect of SD on melanoma cell viability using several biomarkers for cell proliferation and apoptosis. SD inhibits the expression levels of signal transducers and activators of transcription protein (STAT-3 and cyclin D1, an activator of cyclin-dependent kinase 4 (Cdk4. SD treatment also enhances cellular level of tumor suppressor protein 53 (p53 and stimulates cleavage of the nuclear poly (ADP-ribose polymerase (cleaved-PARP. SD also enhances cellular levels of cleaved Caspase-3, -8, -9 and stimulates enzymatic activities of Caspase-3, -8 and -9. These results, in addition to inhibition of cell viability, suggest that SD inhibits melanoma cell proliferation by arresting the cell-division cycle in a Go quiescent phase and activates programmed cell death (apoptosis via extrinsic and intrinsic pathways. Finally, these studies demonstrate that SD shows a very promising chemopreventive effect in melanoma B16F10 tumor cells.

  2. Sarcophine-diol, a skin cancer chemopreventive agent, inhibits proliferation and stimulates apoptosis in mouse melanoma B₁₆F₁₀ cell line.

    Science.gov (United States)

    Szymanski, Pawel T; Kuppast, Bhimanna; Ahmed, Safwat A; Khalifa, Sherief; Fahmy, Hesham

    2012-01-01

    Sarcodiol (SD) is a semi-synthetic derivative of sarcophine, a marine natural product. In our previous work, we reported the significant chemopreventive effects of SD against non-melanoma skin cancer both in vitro and in vivo mouse models. In this investigation, we extended this work to study the effect of sarcodiol on melanoma development, the more deadly form of skin cancer, using the mouse melanoma B₁₆F₁₀ cell line. In this study we report that SD inhibits the de novo DNA synthesis and enhances fragmentation of DNA. We also evaluated the antitumor effect of SD on melanoma cell viability using several biomarkers for cell proliferation and apoptosis. SD inhibits the expression levels of signal transducers and activators of transcription protein (STAT-3) and cyclin D1, an activator of cyclin-dependent kinase 4 (Cdk4). SD treatment also enhances cellular level of tumor suppressor protein 53 (p53) and stimulates cleavage of the nuclear poly (ADP-ribose) polymerase (cleaved-PARP). SD also enhances cellular levels of cleaved Caspase-3, -8, -9 and stimulates enzymatic activities of Caspase-3, -8 and -9. These results, in addition to inhibition of cell viability, suggest that SD inhibits melanoma cell proliferation by arresting the cell-division cycle in a Go quiescent phase and activates programmed cell death (apoptosis) via extrinsic and intrinsic pathways. Finally, these studies demonstrate that SD shows a very promising chemopreventive effect in melanoma B₁₆F₁₀ tumor cells.

  3. Stimulation of murine stem cell proliferation by circulating activities produced during the recovery of a radiation-induced hematopoietic injury. Estimulacion proliferativa de celulas madre hematopoyeticas de raton por actividades circulantes producidas durante la recuperacion de un dano hematopoyetico radioinducido

    Energy Technology Data Exchange (ETDEWEB)

    Grande Azanedo, M.T.

    1989-02-01

    The proliferative activity of CFU-S, low in normal steady state, increases after treatment with different aggressors, i.e., radiation. This stimulation has been attributed in part to a local regulation system of stem cell proliferation, and at least in part to a humoral regulatory system. In the present work it has been investigated the role that circulating activities have in the CFU-S stimulation, by means of in vitro and in vivo incubation assays with diffusion chambers. The results show that bone marrow of mice irradiated with 5 Gy produces in vitro diffusible activities capable of stimulating the CFU-S proliferation. As well with this same dose circulating activities are also produced in vivo. In addition we have observed that these activities are only released during the periods of active hematopoietic regeneration that follow irradiation with moderate doses (1.5 and 5 Gy). In another set of experiments we saw that the stimulating activities are also detected in serum of mice irradiated with 5 Gy. These serum activities modify the proliferative state of very primitive precursors (12 d CFU-S). When the serum activities are added to long term bone marrow cultures the CFU-S are also stimulated to proliferate. Finally, we observed that the radiation-induced serum activities stimulate the proliferation of bone marrow CFU-S when injected into normal mice, suggesting that such activities are involved in the regulation of CFU-S proliferation.

  4. PPARδ deficiency disrupts hypoxia-mediated tumorigenic potential of colon cancer cells.

    Science.gov (United States)

    Jeong, Eunshil; Koo, Jung Eun; Yeon, Sang Hyeon; Kwak, Mi-Kyoung; Hwang, Daniel H; Lee, Joo Young

    2014-11-01

    Peroxisome proliferator-activated receptor (PPAR) δ is highly expressed in colon epithelial cells and closely linked to colon carcinogenesis. However, the role of PPARδ in colon cancer cells in a hypoxic tumor microenvironment is not fully understood. We found that expression of the tumor-promoting cytokines, IL-8 and VEGF, induced by hypoxia (colon cancer cells. Consequently, PPARδ-knockout colon cancer cells exposed to hypoxia and deferoxamine failed to stimulate endothelial cell vascularization and macrophage migration/proliferation, whereas wild-type cells were able to induce angiogenesis and macrophage activation in response to hypoxic stress. Hypoxic stress induced transcriptional activation of PPARδ, but not its protein expression, in HCT116 cells. Exogenous expression of p300 potentiated deferoxamine-induced PPARδ transactivation, while siRNA knockdown of p300 abolished hypoxia- and deferoxamine-induced PPARδ transactivation. PPARδ associated with p300 upon hypoxic stress as demonstrated by coimmunoprecipitation studies. PI3K inhibitors or siRNA knockdown of Akt suppressed the PPARδ transactivation induced by hypoxia and deferoxamine in HCT116 cells, leading to decreased expression of IL-8 and VEGF. Collectively, these results reveal that PPARδ is required for hypoxic stress-mediated cytokine expression in colon cancer cells, resulting in promotion of angiogenesis, macrophage recruitment, and macrophage proliferation in the tumor microenvironment. p300 and the PI3K/Akt pathway play a role in the regulation of PPARδ transactivation induced by hypoxic stress. Our results demonstrate the positive crosstalk between PPARδ in tumor cells and the hypoxic tumor microenvironment and provide potential therapeutic targets for colon cancer.

  5. Triterpenoid α-amyrin stimulates proliferation of human keratinocytes but does not protect them against UVB damage

    DEFF Research Database (Denmark)

    Biskup, Edyta; Gołębiowski, Marek; Gniadecki, Robert

    2012-01-01

    Rhaponticum carthamoides plants ("maral root") are widely used in Siberian folk medicine. The present study reports for the first time the presence of pentacyclic terpenoid, α-amyrin, in methanol extract from leaves of this plant. α-Amyrin induced proliferation of human keratinocytes (HaCaT) by a......Rhaponticum carthamoides plants ("maral root") are widely used in Siberian folk medicine. The present study reports for the first time the presence of pentacyclic terpenoid, α-amyrin, in methanol extract from leaves of this plant. α-Amyrin induced proliferation of human keratinocytes (Ha......CaT) by about 18% while other extract components were ineffective. A panel of biochemical and cell-based assays testing the antioxidative and cytoprotective activites of α-amyrin indicated no antioxidative activity of this compound. α-Amyrin did not protect HaCaT cells against the damage caused by UVB radiation....

  6. Desmocollin 3 mediates follicle stimulating hormone-induced ovarian epithelial cancer cell proliferation by activating the EGFR/Akt signaling pathway.

    Science.gov (United States)

    Yang, Xiao; Wang, Jing; Li, Wen-Ping; Jin, Zhi-Jun; Liu, Xiao-Jun

    2015-01-01

    Follicle-stimulating hormone (FSH) is associated with the pathogenesis of ovarian cancer. We sought to explore whether desmocollin 3 (Dsc3) mediates FSH-induced ovarian epithelial cancer cell proliferation and whether the EGFR/Akt signaling pathway may be involved in this process. Dsc3 positivity in ovarian tissue specimens from 72 patients was assessed by immunohistochemistry. The positive expression rates of Dsc3 were similar in ovarian cancer tissues (24/31:77.4%) and borderline ovarian tumor tissues (18/22:81.8%) (P>0.05), but were significantly higher in these cancerous tissues than in benign ovarian cyst tissues (3/19:15.8%) (Pcancer cells (HO8910, Skov3ip, Skov and Hey cells, but not ES-2 and in borderline ovarian MCV152 tumor cells was higher than in the immortalized ovarian epithelial cell line, Moody. FSH up-regulated the expression of Dsc3 and EGFR in a dose- and time-dependent manner. Furthermore, a converse relationship between the expression of Dsc3, EFGR and PI3K/Akt signaling was elucidated using RNA interference and PI3K/Akt inhibitor in the absence and presence of FSH. A role for these proteins in FSH-induced cell proliferation was verified, highlighting their interdependence in mediating ovarian cancer cell function. These results suggest that Dsc3 can mediate FSH-induced ovarian cancer cell proliferation by activating the EGFR/Akt signaling pathway.

  7. L-arginine stimulates fibroblast proliferation through the GPRC6A-ERK1/2 and PI3K/Akt pathway.

    Directory of Open Access Journals (Sweden)

    Takashi Fujiwara

    Full Text Available L-arginine is considered a conditionally essential amino acid and has been shown to enhance wound healing. However, the molecular mechanisms through which arginine stimulates cutaneous wound repair remain unknown. Here, we evaluated the effects of arginine supplementation on fibroblast proliferation, which is a key process required for new tissue formation. We also sought to elucidate the signaling pathways involved in mediating the effects of arginine on fibroblasts by evaluation of extracellular signal-related kinase (ERK 1/2 activation, which is important for cell growth, survival, and differentiation. Our data demonstrated that addition of 6 mM arginine significantly enhanced fibroblast proliferation, while arginine deprivation increased apoptosis, as observed by enhanced DNA fragmentation. In vitro kinase assays demonstrated that arginine supplementation activated ERK1/2, Akt, PKA and its downstream target, cAMP response element binding protein (CREB. Moreover, knockdown of GPRC6A using siRNA blocked fibroblast proliferation and decreased phosphorylation of ERK1/2, Akt and CREB. The present experiments demonstrated a critical role for the GPRC6A-ERK1/2 and PI3K/Akt signaling pathway in arginine-mediated fibroblast survival. Our findings provide novel mechanistic insights into the positive effects of arginine on wound healing.

  8. Estrogen stimulates the proliferation of human endometrial cancer cells by stabilizing nucleophosmin/B23 (NPM/B23).

    Science.gov (United States)

    Chao, Angel; Lin, Chiao-Yun; Tsai, Chia-Lung; Hsueh, Swei; Lin, Ying-Yu; Lin, Cheng-Tao; Chou, Hung-Hsueh; Wang, Tzu-Hao; Lai, Chyong-Huey; Wang, Hsin-Shih

    2013-02-01

    Unopposed estrogen exposure is an important factor in the tumorigenesis of endometrial cancer. Nucleophosmin/B23 (NPM/B23), a phosphoprotein that has pleiotropic functions in cells, plays an important role in various cancers. However, the regulatory role of NPM/B23 in estrogen signaling in endometrial cancer has not been explored. Here, we report that NPM/B23 was required for estrogen-induced endometrial proliferation, and the increase in NPM/B23 was estrogen receptor α-dependent. Furthermore, estrogen increased NPM/B23 protein levels by repressing its ubiquitination and subsequently stabilizing the protein. The overexpression of the alternate reading frame (ARF) suppressed the estrogen-induced increase in the NPM/B23 protein levels, indicating that ARF inhibited the observed estrogen-mediated NPM/B23 stabilization. Our results suggest that one of the effects of estrogen on endometrial proliferation is the suppression of the NPM/B23-ARF interaction and the subsequent increase in NPM/B23 protein levels. This novel characterization of NPM/B23 in estrogen-mediated cell proliferation may extend our understanding of the tumorigenesis of steroid hormone-related cancers.

  9. Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Min Sook [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Woo, Min-Yeong [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Department of Biomedical Sciences, The Graduate School, Ajou University (Korea, Republic of); Kwon, Daeho [Department of Microbiology, Kwandong University College of Medicine, Gangneung, Gangwon-do 210-701 (Korea, Republic of); Hong, Allen E. [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Song, Kye Yong [Department of Pathology, Chung-Ang University College of Medicine, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Park, Sun [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Lim, In Kyoung [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of)

    2014-10-01

    In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with the WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.

  10. Choukroun's platelet-rich fibrin (PRF) stimulates in vitro proliferation and differentiation of human oral bone mesenchymal stem cell in a dose-dependent way.

    Science.gov (United States)

    Dohan Ehrenfest, David M; Doglioli, Pierre; de Peppo, Giuseppe M; Del Corso, Marco; Charrier, Jean-Baptiste

    2010-03-01

    Choukroun's platelet-rich fibrin (PRF) is an autologous leukocyte- and platelet-rich fibrin biomaterial. The purpose of this study was to analyse the in vitro effects of PRF on human bone mesenchymal stem cells (BMSC), harvested in the oral cavity after preimplant endosteal stimulation. BMSCs from primary cultures were cultivated with or without a PRF membrane originating from the same donor as for the cells, in proliferation or osteoblastic differentiation conditions. After 7 days, the PRF membranes were removed. A series of cultures were performed using 2 PRF membranes, in order to measure the dose-dependent effect. Cell counts, cytotoxicity tests, alkaline phosphatase (ALP) activity quantification, Von Kossa staining and mineralisation nodules counts were performed at 3, 7, 14, 21 and 28 days. A last independent series was carried on up to 14 days, for a morphological scanning electron microscope (SEM) observation. PRF generated a significant stimulation of the BMSC proliferation and differentiation throughout the experimental period. This effect was dose-dependent during the first weeks in normal conditions, and during the whole experimentation in differentiation conditions. The cultures without PRF in differentiation conditions did not rise above the degree of differentiation of the cultures in normal conditions with 1 or 2 PRF up to the 14th and 28th day, respectively. The SEM culture analysis at day 14 allowed to show the mineralisation nodules which were more numerous and more structured in the groups with PRF compared to the control groups. This double contradictory proliferation/differentiation result may be due to the numerous components of PRF, particularly the presence of leukocytes: any culture with PRF is in fact a coculture with leukocytes. It could be the source of differential geographic regulation processes within the culture. The combination of oral BMSC and PRF might offer many potential clinical and biotechnological applications, and deserves

  11. Effect of IL-10 gene transmission on the PTg-stimulated splenocytes proliferation and Th1 cytokines production from experimental autoimminue thyroiditis rats

    Institute of Scientific and Technical Information of China (English)

    Wei Tang; Cuiping Liu; Youwen Qin; Yue Jia; Xiaodong Mao; Chao Liu

    2007-01-01

    Objective: To investigate the effects of gene therapy with IL-10 on PTg-induced proliferation of splenocytes and Th1 cytokine production from PTg-stimulated splenocytes. Methods: EAT rats were divided into four groups:group A (PBS+PLL) , group B (pORF+PLL), group C (pORFmIL10+PLL), and group D (pORFmIL10+ MEM). The substances mixed with lipofectamine were injected into the thyroid tissues of rats on the 18th dday after immunization. The rats were sacrificed at the 8th week. In vitro proliferative responses to ConA and different concentration of PTg were measured by culturing 4×105 splenocytes pulsed with 18.SKBq of [3H] thymidine for the final 12h and then harvested for liquid scintillation counting. In vitro splenocytes were cultured with PTg (25 mg/L). Th1 cytokine IFN-γ,TNF-αand IL-2 were detected by ELISA. Results: The proliferative response to PTg was suppressed in group C, compared with that of group A and B (P<0.05). The levels of IFN-γ,TNF-oand IL-2 in the supernatant of PTg-stimulated splenocytes were 3548.25 ± 779.47 pg/ml, 27.66±10.50 pg/ml and 3617.73± 609.15 pg/ml, respectively,which were much lower in group C than those in group A and B(P<0.01, P<0.05, P<0.001, respectively). Conclusion: IL-10 gene transmission in thyroid tissues could inhibit PTg specific proliferation of splenocytes from EAT rats and the secretion of Thl cytokines from PTg-stimulated splenocytes.

  12. [Effect of moxa-burning heat stimulating Liangmen (ST 21) and Zusanli (ST 36) on proliferation and apoptosis signaling proteins in rats with stress-induced gastric ulcer].

    Science.gov (United States)

    Peng, Li; Wang, Yadong; Chang, Xiaorong; Wu, Huangan; Liu, Mi; Wang, Hong; Chen, Jiaolong; Wang Chao; Quan, Renfu; Yang, Zongbao

    2016-06-01

    To observe the effect of moxa-burning heat stimulating acupoints of Liangmen (ST 21) and Zusanli (ST 36) on the proliferation and apoptosis signaling proteins in rats with stress-induced gastric ulcer. Forty rats were randomly divided into four groups: negative control (NC), ulcer control (UC), acupoints of stomach meridian (ASM), and acupoints control (AC). The acute gastric ulcer model was established by bound and water immersion. Rats in NC and UC groups didn't receive any moxa-burning heat stimulating treatment, while rats in ASM and AC groups were treated with buringmoxa heat stimulating the acupoints of Liangmen (ST 21) and Zusanli (ST 36) and their controlled points, respectively. Rats in all groups were sacrificed after 12 consecutive days treatment. The ulcer index was evaluated by using Guth's method. The expression of tumor necrosis factor-alpha (TNF-α), apoptotic protease activating facter-1 (Apaf-1), Caspase-3, p21 activated kinase 1 (PAK1), extracellular regulated protein kinases 2 (ERK2), phosphorylated ERK2 (pERK2), phosphoinositide 3-kinase (PI3K) and RAC-alpha serine/threonine-protein kinase (Akt) in gastric mucosa was detected by enzyme linked immunosorbent assay (ELISA). Compared with UC group, the ulcer index of ASM and AC groups decreased, and the injured gastric mucosa was improved, the expression of TNF-α, Apaf-1 and Caspase-3 in gastric mucosa was significantly reduced (P gastric mucosa was significantly increased (P gastric mucosal lesion probably by inhibiting cell apoptosis and promoting cell proliferation in stress-induced gastric ulcer.

  13. Typha latifolia L. fruit polysaccharides induce the differentiation and stimulate the proliferation of human keratinocytes in vitro.

    Science.gov (United States)

    Gescher, Kirsten; Deters, Alexandra M

    2011-09-01

    In Northern America Typha latifolia L. (Typhaceae) fruits are used for more than 4000 years for treatment of skin disorders, burns and as wound dressing to absorb the ichors. The following studies attempted to characterize water-soluble polysaccharides from aqueous Typha latifolia extracts and to investigate the influence of the polymers on cell physiology of human dermal fibroblasts (NHDF) and epidermal keratinocytes (NHEK). Water-soluble raw polysaccharides (RPS) were isolated from Typha latifolia fruits and fractionated by anion exchange chromatography (AEC) and size exclusion chromatography (GPC). Fractions obtained were characterized concerning monosaccharide composition by HPAEC-PAD. The bioactivity of the polysaccharides was investigated on cell viability, proliferation, differentiation and gene expression NHDF of NHEK. RPS was fractionated into 5 heterodisperse fractions (TL1-TL5). The polysaccharides were composed mainly of glucose (more than 50% in RPS and TL4), galactose, xylose, mannose, glucuronic acid, galacturonic acid, arabinose, ribose, fucose, rhamnose, and fructose with differing amounts concerning to RPS and AEC-fractions. Proteins were detected in the RPS (10%) and to a less extend in TL1-TL3 (1-3%). TL1-TL3 significantly increased the proliferation of keratinocytes, whereas TL4 was shown to be a potent inductor of the early differentiation process of keratinocytes. Gene expression analysis supported these results since Smad3 and PKC-α, known to be part of signal pathways leading to cell differentiation, were significantly up regulated. Effects on fibroblasts were not observed, indicating cell specific activity of the polysaccharides. The results clearly indicate a rationale for the traditional use of Typha latifolia fruits extracts for wound healing to the strong stimulatory activity of the polysaccharides on keratinocytes proliferation and early differentiation, major activities necessary for potent wound-healing agents. Copyright © 2011

  14. Identification of plant extracts with potential antidiabetic properties: effect on human peroxisome proliferator-activated receptor (PPAR), adipocyte differentiation and insulin-stimulated glucose uptake.

    Science.gov (United States)

    Christensen, Kathrine B; Minet, Ariane; Svenstrup, Henrik; Grevsen, Kai; Zhang, Hongbin; Schrader, Eva; Rimbach, Gerald; Wein, Silvia; Wolffram, Siegfried; Kristiansen, Karsten; Christensen, Lars P

    2009-09-01

    Thiazolidinediones (TZDs) are insulin sensitizing drugs used to treat type 2 diabetes. The primary target of the TZDs is the peroxisome proliferator-activated receptor (PPAR) gamma, a key regulator of adipogenesis and glucose homeostasis. Currently prescribed TZDs are full PPARgamma agonists, and their use is associated with several side effects. Partial PPARgamma agonists appear to be associated with fewer side effects but may still confer the desired insulin sensitizing action. Extracts from common medicinal/food plants were tested in a screening platform comprising a series of bioassays, including tests for PPARgamma, alpha and delta transactivation, adipocyte differentiation and insulin-stimulated glucose uptake, allowing identification of plants containing potentially interesting PPAR agonists. Twenty-two plant extracts out of 133 were found to increase insulin-stimulated glucose uptake and 18 extracts were found to activate PPARgamma, 3 to activate PPARalpha and gamma, 6 to activate PPARdelta and gamma, and 9 to activate PPARgamma, alpha and delta. Among the 24 different plant species tested in the platform, 50% were shown to contain compounds capable of activating PPARgamma and stimulating insulin-dependent glucose uptake with no or little effect on adipocyte differentiation warranting further studies and characterization.

  15. Red (660 nm) or near-infrared (810 nm) photobiomodulation stimulates, while blue (415 nm), green (540 nm) light inhibits proliferation in human adipose-derived stem cells.

    Science.gov (United States)

    Wang, Yuguang; Huang, Ying-Ying; Wang, Yong; Lyu, Peijun; Hamblin, Michael R

    2017-08-10

    We previously showed that blue (415 nm) and green (540 nm) wavelengths were more effective in stimulating osteoblast differentiation of human adipose-derived stem cells (hASC), compared to red (660 nm) and near-infrared (NIR, 810 nm). Intracellular calcium was higher after blue/green, and could be inhibited by the ion channel blocker, capsazepine. In the present study we asked what was the effect of these four wavelengths on proliferation of the hASC? When cultured in proliferation medium there was a clear difference between blue/green which inhibited proliferation and red/NIR which stimulated proliferation, all at 3 J/cm(2). Blue/green reduced cellular ATP, while red/NIR increased ATP in a biphasic manner. Blue/green produced a bigger increase in intracellular calcium and reactive oxygen species (ROS). Blue/green reduced mitochondrial membrane potential (MMP) and lowered intracellular pH, while red/NIR had the opposite effect. Transient receptor potential vanilloid 1 (TRPV1) ion channel was expressed in hADSC, and the TRPV1 ligand capsaicin (5uM) stimulated proliferation, which could be abrogated by capsazepine. The inhibition of proliferation caused by blue/green could also be abrogated by capsazepine, and by the antioxidant, N-acetylcysteine. The data suggest that blue/green light inhibits proliferation by activating TRPV1, and increasing calcium and ROS.

  16. Connective tissue growth factor stimulates the proliferation, migration and differentiation of lung fibroblasts during paraquat-induced pulmonary fibrosis.

    Science.gov (United States)

    Yang, Zhizhou; Sun, Zhaorui; Liu, Hongmei; Ren, Yi; Shao, Danbing; Zhang, Wei; Lin, Jinfeng; Wolfram, Joy; Wang, Feng; Nie, Shinan

    2015-07-01

    It is well established that paraquat (PQ) poisoning can cause severe lung injury during the early stages of exposure, finally leading to irreversible pulmonary fibrosis. Connective tissue growth factor (CTGF) is an essential growth factor that is involved in tissue repair and pulmonary fibrogenesis. In the present study, the role of CTGF was examined in a rat model of pulmonary fibrosis induced by PQ poisoning. Histological examination revealed interstitial edema and extensive cellular thickening of interalveolar septa at the early stages of poisoning. At 2 weeks after PQ administration, lung tissue sections exhibited a marked thickening of the alveolar walls with an accumulation of interstitial cells with a fibroblastic appearance. Masson's trichrome staining revealed a patchy distribution of collagen deposition, indicating pulmonary fibrogenesis. Western blot analysis and immunohistochemical staining of tissue samples demonstrated that CTGF expression was significantly upregulated in the PQ-treated group. Similarly, PQ treatment of MRC-5 human lung fibroblast cells caused an increase in CTGF in a dose-dependent manner. Furthermore, the addition of CTGF to MRC-5 cells triggered cellular proliferation and migration. In addition, CTGF induced the differentiation of fibroblasts to myofibroblasts, as was evident from increased expression of α-smooth muscle actin (α-SMA) and collagen. These findings demonstrate that PQ causes increased CTGF expression, which triggers proliferation, migration and differentiation of lung fibroblasts. Therefore, CTGF may be important in PQ-induced pulmonary fibrogenesis, rendering this growth factor a potential pharmacological target for reducing lung injury.

  17. EGF–FGF{sub 2} stimulates the proliferation and improves the neuronal commitment of mouse epidermal neural crest stem cells (EPI-NCSCs)

    Energy Technology Data Exchange (ETDEWEB)

    Bressan, Raul Bardini; Melo, Fernanda Rosene; Almeida, Patricia Alves; Bittencourt, Denise Avani; Visoni, Silvia; Jeremias, Talita Silva [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Costa, Ana Paula; Leal, Rodrigo Bainy [Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Trentin, Andrea Gonçalves, E-mail: andrea.trentin@ufsc.br [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil)

    2014-09-10

    Epidermal neural crest stem cells (EPI-NCSCs), which reside in the bulge of hair follicles, are attractive candidates for several applications in cell therapy, drug screening and tissue engineering. As suggested remnants of the embryonic neural crest (NC) in an adult location, EPI-NCSCs are able to generate a wide variety of cell types and are readily accessible by a minimally invasive procedure. Since the combination of epidermal growth factor (EGF) and fibroblast growth factor type 2 (FGF{sub 2}) is mitogenic and promotes the neuronal commitment of various stem cell populations, we examined its effects in the proliferation and neuronal potential of mouse EPI-NCSCs. By using a recognized culture protocol of bulge whiskers follicles, we were able to isolate a population of EPI-NCSCs, characterized by the migratory potential, cell morphology and expression of phenotypic markers of NC cells. EPI-NCSCs expressed neuronal, glial and smooth muscle markers and exhibited the NC-like fibroblastic morphology. The treatment with the combination EGF and FGF{sub 2}, however, increased their proliferation rate and promoted the acquisition of a neuronal-like morphology accompanied by reorganization of neural cytoskeletal proteins βIII-tubulin and nestin, as well as upregulation of the pan neuronal marker βIII-tubulin and down regulation of the undifferentiated NC, glial and smooth muscle cell markers. Moreover, the treatment enhanced the response of EPI-NCSCs to neurogenic stimulation, as evidenced by induction of GAP43, and increased expression of Mash-1 in neuron-like cell, both neuronal-specific proteins. Together, the results suggest that the combination of EGF–FGF2 stimulates the proliferation and improves the neuronal potential of EPI-NCSCs similarly to embryonic NC cells, ES cells and neural progenitor/stem cells of the central nervous system and highlights the advantage of using EGF–FGF{sub 2} in neuronal differentiation protocols. - Highlights: • EPI

  18. Regulatory effect of hypoxia-inducible factor-1α on hCG-stimulated endothelin-2 expression in granulosa cells from the PMSG-treated rat ovary.

    Science.gov (United States)

    Zhang, Jisen; Zhang, Zhenghong; Wu, Yanqing; Chen, Liyun; Luo, Qianping; Chen, Jiajie; Huang, Xiaohong; Cheng, Yong; Wang, Zhengchao

    2012-01-01

    Endothelin (ET)-2 plays a crucial role in ovarian ovulation in mammals. The present study was designed to test the hypothesis that hypoxia-inducible factor (HIF)-1α-mediated transcriptional activation contributes to the increased expression of ET-2 gene in response to hCG in rat ovarian granulosa cells (GCs) during gonadotropin-induced superovulation. By real-time RT-PCR analysis, ET-2 mRNA expression was found to significantly increase in cultured ovarian GCs after treatment with hCG, or even N-carbobenzoxyl-L-leucinyl-L-leucinyl-L-norvalinal (MG-132), while this increased ET-2 mRNA expression could also be blocked by ferrous ammonium sulfate (FAS) under human chorionic gonadotropin (hCG) treatment. Further analysis also found that these changes of ET-2 mRNA were consistent with HIF-1α expression or HIF-1 activity, and HIF-1α inhibitor echinomycin inhibited ovulation in rats. Taken together, these results indicate that ET-2 is transcriptionally activated by hCG through HIF-1α-mediated mechanism in GCs. This HIF-1α-induced transcriptional activation may be one of the important mechanisms mediating the increase of ET-2 expression in GCs during the gonadotropin-induced mammalian ovulatory process in vivo.

  19. Preconditioning of brain slices against hypoxia induced injury by a Gynostemma pentaphyllum extract--stimulation of anti-oxidative enzyme expression.

    Science.gov (United States)

    Schild, L; Cotte, T; Keilhoff, G; Brödemann, R

    2012-06-15

    A short period of hypoxia/hypoglycaemia (oxygen and glucose deprivation, OGD) induced by perfusion with O(2)/glucose-free medium caused immediate loss and incomplete restoration of evoked field potentials in the CA1 region of transverse hippocampus slices. OGD-dependent decrease in evoked field potentials can be prevented by a proceeding short OGD event (preconditioning). We report about a study investigating the effect of an ethanolic Gynostemma pentaphyllum extract on evoked field potentials when administered before the OGD episode. Using this procedure, the extract completely protected the cells of the slices from functional injury. In an astroglia rich cell culture the ethanolic Gynostemma pentaphyllum extract caused within 48 h of cultivation increased protein and activity levels of the anti-oxidative enzymes manganese superoxide dismutase (Mn-SOD) and glutathione peroxidase (GPx). Consequently, the cellular H(2)O(2) concentration remained at a low level. These data suggest that the Gynostemma pentaphyllum-mediated increase in antioxidative enzyme activities may contribute to the protection of transverse hippocampus slices from OGD induced functional injury. Our results demonstrate that the prophylactic administration of the ethanolic extract from Gynostemma pentaphyllum has a high potential to protect from ischemia/reperfusion injury. Copyright © 2012 Elsevier GmbH. All rights reserved.

  20. Hypoxia induces adipogenic differentitation of myoblastic cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Itoigawa, Yoshiaki [Tohoku University School of Medicine, Sendai (Japan); Juntendo University School of Medicine, Tokyo (Japan); Kishimoto, Koshi N., E-mail: kishimoto@med.tohoku.ac.jp [Tohoku University School of Medicine, Sendai (Japan); Okuno, Hiroshi; Sano, Hirotaka [Tohoku University School of Medicine, Sendai (Japan); Kaneko, Kazuo [Juntendo University School of Medicine, Tokyo (Japan); Itoi, Eiji [Tohoku University School of Medicine, Sendai (Japan)

    2010-09-03

    Research highlights: {yields} C2C12 and G8 myogenic cell lines treated by hypoxia differentiate into adipocytes. {yields} The expression of C/EBP{beta}, {alpha} and PPAR{gamma} were increased under hypoxia. {yields} Myogenic differentiation of C2C12 was inhibited under hypoxia. -- Abstract: Muscle atrophy usually accompanies fat accumulation in the muscle. In such atrophic conditions as back muscles of kyphotic spine and the rotator cuff muscles with torn tendons, blood flow might be diminished. It is known that hypoxia causes trans-differentiation of mesenchymal stem cells derived from bone marrow into adipocytes. However, it has not been elucidated yet if hypoxia turned myoblasts into adipocytes. We investigated adipogenesis in C2C12 and G8 murine myogenic cell line treated by hypoxia. Cells were also treated with the cocktail of insulin, dexamethasone and IBMX (MDI), which has been known to inhibit Wnt signaling and promote adipogenesis. Adipogenic differentiation was seen in both hypoxia and MDI. Adipogenic marker gene expression was assessed in C2C12. CCAAT/enhancer-binding protein (C/EBP) {beta}, {alpha} and peroxisome proliferator activating receptor (PPAR) {gamma} were increased by both hypoxia and MDI. The expression profile of Wnt10b was different between hypoxia and MDI. The mechanism for adipogenesis of myoblasts in hypoxia might be regulated by different mechanism than the modification of Wnt signaling.

  1. Constituents from Cistus salvifolius (Cistaceae) activate peroxisome proliferator-activated receptor-γ but not -δ and stimulate glucose uptake by adipocytes.

    Science.gov (United States)

    Kühn, Claudia; Arapogianni, Niki Eliza; Halabalaki, Maria; Hempel, Jana; Hunger, Nicole; Wober, Jannette; Skaltsounis, Alexios Leandros; Vollmer, Günter

    2011-03-01

    A number of medicinal/culinary herbs have been reported to improve glucose metabolism and to yield hypoglycemic effects in patients with diabetes. Since stimulation of insulin sensitivity appears to be a potential mechanism, peroxisome proliferator-activated receptor (PPAR) γ is a likely target molecule for small lipophilic compounds derived from endogenous metabolism and nutrition. Functionally, PPAR γ integrates the control of energy, lipid, and glucose homeostasis. In addition, PPAR δ activity is involved in energy expenditure. Therefore the aim of this study was to investigate whether PPAR γ and PPAR δ as well as the stimulation of glucose uptake is activated by botanical products. CISTUS SALVIFOLIUS (Cistaceae) has been identified as a candidate botanical in a preliminary screening of extracts from medicinal plants of Greek flora. In a bioguided approach, crude extracts, fractions and in the end purified compounds have been evaluated for PPAR γ and PPAR δ specific activities using cell-based transactivation assays. Glucose uptake was measured by nonradioactive 2-[ N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) uptake. Concerning PPAR γ several extracts induced reporter gene activity, and clear dose-response patterns (0.1-100 µg/mL) could be established in the case of the cyclohexane and dichloromethane extracts. Isolation of individual compounds from the cyclohexane extract revealed that at least 6 out of 7 compounds isolated were active with TRANS-cinnamic acid showing a clear dose-response pattern. In contrast, they were found to be inactive on PPAR δ. The same compounds, however, were also active in stimulating glucose uptake into 3T3-L1 adipocytes. In summary, the bioguided fractionation of CISTUS SALVIFOLIUS yields PPAR γ stimulating metabolites with differing chemical natures. In conclusion, PPAR γ represents a candidate molecule for the mediation of improvement of glucose metabolism by botanical/nutritional products.

  2. Neuropeptide Y Stimulates Proliferation and Migration of Vascular Smooth Muscle Cells from Pregnancy Hypertensive Rats via Y1 and Y5 Receptors.

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    Full Text Available The increased proliferation and migration of vascular smooth muscle cells (VSMCs play important roles in pathophysiological remodeling of arteries during hypertension in pregnancy. However, the mechanisms involved in this process remain unclear. We hypothesized that Neuropeptide Y (NPY, which is a potent mitogenic peptide, participates in modulating proliferation and migration of VSMCs during hypertension in pregnancy. Using pregnant hypertensive rats, induced by intraperitoneal injection of L-nitro-arginine methylester (L-NAME, the plasma concentration of NPY was detected. Open angle, which reflects the non-uniform remodeling with high sensitivity, was used to detect the pathophysiological vascular remodeling in vivo. The results revealed that NPY concentration and artery open angle were both significantly increased in rats with hypertension in pregnant. The underlying mechanism of elevated NPY on vascular remodeling were further analyzed by using cultured VSMCs in vitro. In cultured VSMCs, NPY most effectively stimulated the migration and proliferation of VSMCs at 10-6 mol/L, similar to the plasma concentration in L-NAME hypertension in pregnant rats. NPY up-regulated the expressions of both Y1 and Y5 receptors, increased the phosphorylations of STAT3 on Tyr705 and Ser727 residues, and induced the expression of c-Fos. The NPY-induced VSMCs proliferation was reduced by Y5 receptor antagonist, and fully blocked by combinations with other antagonist, such as Y2+Y5, Y1+Y5, and Y1+Y2+Y5. In contrast, the NPY-induced VSMC migration was blocked by either Y receptor antagonist or any combination of Y receptor antagonists. These results suggest that the elevated plasma concentration of NPY during hypertension in pregnancy may induce VSMC proliferation mainly via Y5 receptor, which subsequently modulate STAT3 and c-Fos signaling pathways to result in the vascular remodeling. These results also suggest that NPY mainly acts on VSMCs in vitro via Y1, Y5

  3. M2 Phenotype Microglia-derived Cytokine Stimulates Proliferation and Neuronal Differentiation of Endogenous Stem Cells in Ischemic Brain

    Science.gov (United States)

    Choi, Ja Yong; Kim, Jong Youl; Kim, Jae Young; Park, Joohyun; Lee, Won Taek

    2017-01-01

    Microglia play a key role in the immune response and inflammatory reaction that occurs in response to ischemic stroke. Activated microglia promote neuronal damage or protection in injured brain tissue. Extracellular signals polarize the microglia towards the M1/M2 phenotype. The M1/M2 phenotype microglia released pro- and anti-inflammatory cytokines which induce the activation of neural stem/progenitor cells (NSPCs). In this study, we investigated how the cytokines released by microglia affect the activation of NSPCs. First, we treated BV2 cells with a lipopolysaccharide (LPS; 20 ng/ml) for M1 phenotype microglia and interleukin-4 (IL-4; 20 ng/ml) for M2 phenotype microglia in BV2 cells. Mice were subjected to transient middle cerebral artery occlusion (tMCAO) for 1 h. In ex vivo, brain sections containing the subventricular zone (SVZ) were cultured in conditioned media of M1 and M2 phenotype-conditioned media for 3 d. We measured the expression of cytokines in the conditioned media by RT-PCR and ELISA. The M2 phenotype microglia-conditioned media led to the proliferation and neural differentiation of NSPCs in the ipsilateral SVZ after ischemic stroke. The RT-PCR and ELISA results showed that the expression of TGF-α mRNA was significantly higher in the M2 phenotype microglia-conditioned media. These data support that M2 phenotype microglia-derived TGF-α is one of the key factors to enhance proliferation and neural differntiation of NSPCs after ischemic stroke.

  4. Stand-up exercise training facilitates muscle recovery from disuse atrophy by stimulating myogenic satellite cell proliferation in mice.

    Science.gov (United States)

    Itoh, Yuta; Hayakawa, Kimihide; Mori, Tomohiro; Agata, Nobuhide; Inoue-Miyazu, Masumi; Murakami, Taro; Sokabe, Masahiro; Kawakami, Keisuke

    2014-11-01

    Determining the cellular and molecular recovery processes in inactivity - or unloading -induced atrophied muscles should improve rehabilitation strategies. We assessed the effects of stand-up exercise (SE) training on the recovery of atrophied skeletal muscles in male mice. Mice were trained to stand up and press an elevated lever in response to a light-tone cue preceding an electric foot shock and then subjected to tail suspension (TS) for 2 weeks to induce disuse atrophy in hind limb muscles. After release from TS, mice were divided into SE-trained (SE cues: 25 times per set, two sets per day) and non-SE-trained groups. Seven days after the training, average myofiber cross-sectional area (CSA) of the soleus muscle was significantly greater in the SE-trained group than in the non-SE-trained group (1843 ± 194 μm(2) vs. 1315 ± 153 μm(2)). Mean soleus muscle CSA in the SE trained group was not different from that in the CON group subjected to neither TS nor SE training (2005 ± 196 μm(2)), indicating that SE training caused nearly complete recovery from muscle atrophy. The number of myonuclei per myofiber was increased by ~60% in the SE-trained group compared with the non-SE-trained and CON groups (0.92 ± 0.03 vs. 0.57 ± 0.03 and 0.56 ± 0.11, respectively). The number of proliferating myonuclei, identified by 5-ethynyl-2'-deoxyuridine staining, increased within the first few days of SE training. Thus, it is highly likely that myogenic satellite cells proliferated rapidly in atrophied muscles in response to SE training and fused with existing myofibers to reestablish muscle mass.

  5. ETV6-PDGFRB and FIP1L1-PDGFRA stimulate human hematopoietic progenitor cell proliferation and differentiation into eosinophils: the role of nuclear factor-κB

    Science.gov (United States)

    Montano-Almendras, Carmen P.; Essaghir, Ahmed; Schoemans, Hélène; Varis, Inci; Noël, Laura A.; Velghe, Amélie I.; Latinne, Dominique; Knoops, Laurent; Demoulin, Jean-Baptiste

    2012-01-01

    Background ETV6-PDGFRB (also called TEL-PDGFRB) and FIP1L1-PDGFRA are receptor-tyrosine kinase fusion genes that cause chronic myeloid malignancies associated with hypereosinophilia. The aim of this work was to gain insight into the mechanisms whereby fusion genes affect human hematopoietic cells and in particular the eosinophil lineage. Design and Methods We introduced ETV6-PDGFRB and FIP1L1-PDGFRA into human CD34+ hematopoietic progenitor and stem cells isolated from umbilical cord blood. Results Cells transduced with these oncogenes formed hematopoietic colonies even in the absence of cytokines. Both oncogenes also stimulated the proliferation of cells in liquid culture and their differentiation into eosinophils. This model thus recapitulated key features of the myeloid neoplasms induced by ETV6-PDGFRB and FIP1L1-PDGFRA. We next showed that both fusion genes activated the transcription factors STAT1, STAT3, STAT5 and nuclear factor-κB. Phosphatidylinositol-3 kinase inhibition blocked nuclear factor-κB activation in transduced progenitor cells and patients’ cells. Nuclear factor-κB was also activated in the human FIP1L1-PDGFRA-positive leukemia cell line EOL1, the proliferation of which was blocked by borte-zomib and the IκB kinase inhibitor BMS-345541. A mutant IκB that prevents nuclear translocation of nuclear factor-κB inhibited cell growth and the expression of eosinophil markers, such as the interleukin-5 receptor and eosinophil peroxidase, in progenitors transduced with ETV6-PDGFRB. In addition, several potential regulators of this process, including HES6, MYC and FOXO3 were identified using expression microarrays. Conclusions We show that human CD34+ cells expressing PDGFR fusion oncogenes proliferate autonomously and differentiate towards the eosinophil lineage in a process that requires nuclear factor-κB. These results suggest new treatment possibilities for imatinib-resistant myeloid neoplasms associated with PDGFR mutations. PMID:22271894

  6. Discriminative analysis of rat Sertoli and peritubular cells and their proliferation in vitro: evidence for follicle-stimulating hormone-mediated contact inhibition of Sertoli cell mitosis.

    Science.gov (United States)

    Schlatt, S; de Kretser, D M; Loveland, K L

    1996-08-01

    A new methodological approach using immunohistochemical markers for Sertoli cells (alpha inhibin), peritubular cells (alpha smooth muscle actin), and S-phase cells (bromodeoxyuridine; BrdU) is presented that allows an accurate and simultaneous analysis of morphogenetic and mitogenic changes occurring in vitro. Sertoli cells and peritubular cells were isolated by sequential enzymatic digestion from 7-day-old rats. Laminin, as a major component of the extracellular matrix of the seminiferous tubule, and FSH, as a hormone stimulating Sertoli cell proliferation, were tested for their ability to influence the morphology or mitotic activity of the cultured cells. After fixation, the coverslips were stained for these antigens with use of specific primary antibodies and horseradish peroxidase- or alkaline phosphatase-labeled secondary antibodies for visualization of the respective antigens with different-colored precipitates. This approach allowed us to distinguish the two cell populations, which could not be done unequivocally without the antibody staining. We scored striking changes in cell densities and cell ratios during the culture period. Peritubular cells showed a consistently higher BrdU-labeling index than Sertoli cells. While Sertoli cells were not labeled until Day 7, peritubular cells proliferated as soon as on Day 3, and their density doubled from Day 3 to Day 7. A linear negative correlation was established for Sertoli cell proliferation in response to their local density on the coverslip, indicating contact inhibition as a signal for cessation of mitosis. At high cell densities, this inhibition was partially overcome in the presence of FSH. The presence of laminin had striking effects on the morphogenetic response but only a minor influence on mitogenesis.

  7. MDH2 Stimulated by Estrogen-GPR30 Pathway Down-Regulated PTEN Expression Promoting the Proliferation and Invasion of Cells in Endometrial Cancer

    Directory of Open Access Journals (Sweden)

    Yan Zhuang

    2017-04-01

    Full Text Available PURPOSE: The relationship between endometrial carcinoma and cellular metabolism is unknown. In endometrial cancer, mutation rate of PTEN has been reported very high. Malate dehydrogenase 2 (MDH2 is one of the isoforms of malate dehydrogenase, which is involved in citric acid cycle in mitochondria. Our study aimed to investigate the role MDH2 played in PTEN-regulated endometrial carcinoma. METHODS: To reveal the expression of MDH2 and the co-localization of PTEN and MDH2, immunohistochemistry and immunofluorescent staining were used. Western blot, Real-time PCR, RNA interference and overexpression plasmid DNA transfection were performed to investigate the relationship between PTEN and MDH2 as well as the impact of E2 on the expression of PTEN and MDH2, while CCK8, transwell and flow cytometric analysis were carried out to evaluate the proliferation, migration and invasion and apoptosis of endometrial carcinoma cell lines. RESULTS: Our results demonstrated that as a metabolism related enzyme, MDH2 was overexpressed in endometrial carcinoma tissues and related to the grade of the cancer (P = .038. Western blot, Real-time PCR and immunofluorescent staining revealed MDH2 inhibited the expression of PTEN and was co-localized with PTEN in the cytoplasm of endometrial carcinoma. Proliferation, transwell and apoptosis assay suggested that MDH2 enhanced the proliferation, migration and invasion but inhibited the apoptosis of endometrial cancer cell line through suppressing PTEN. Furthermore, E2 inhibited the expression level of PTEN but enhanced MDH2 via GPR30. CONCLUSIONS: Our study demonstrated that MDH2, stimulated by estrogen, was involved in the development of PTEN-regulated endometrial carcinoma through GPR30-related pathway.

  8. Lithium stimulates human bone marrow derived mesenchymal stem cell proliferation through GSK-3β-dependent β-catenin/Wnt pathway activation.

    Science.gov (United States)

    Zhu, Zhenzhong; Yin, Junhui; Guan, Junjie; Hu, Bin; Niu, Xin; Jin, Dongxu; Wang, Yang; Zhang, Changqing

    2014-12-01

    Mesenchymal stem cells (MSCs) are multipotent cells that have been widely used in cell based transplantation therapy. The use of MSCs requires in vitro expansion in order to fulfill their regenerative capacity. Therefore the proliferative ability of MSCs is one of the key factors which determine MSC therapeutic efficacy. In the present study, we showed for the first time that lithium, a well-known antidepressant, reversibly promoted the proliferation of human bone marrow derived MSCs in vitro. MSCs treated with 5 mm lithium proliferated more rapidly than untreated cells without undergoing apoptosis. Lithium increased the proportion of cells in S phase as well as cyclin D1 expression. Mechanistic studies revealed that these effects were dependent upon the activation of the glycogen synthase kinase 3β (GSK-3β) mediated canonical Wnt pathway. Lithium induced Ser9 phosphorylation, which results in the inhibition of GSK-3β activity, β-catenin accumulation and Wnt pathway activation. Utilizing a specific GSK-3β inhibitor SB216763 or siRNA-mediated inhibition of GSK-3β produced effects similar to those induced by lithium. In contrast, either quercetin, an inhibitor of the β-catenin/TCF pathway, or siRNA-mediated knockdown of β-catenin abolished the proliferative effect of lithium, suggesting that lithium stimulates MSC proliferation via the GSK-3β-dependent β-catenin/Wnt pathway. Collectively, these studies elucidate a novel role of lithium, which may not only provide a simple and effective way to strengthen MSC transplantation therapy efficacy but also shed light on lithium's clinical application for the treatment of certain disorders resulting from β-catenin/Wnt pathway suppression.

  9. [Cultivation of continuous cell lines on the substrate of carbon nanotubes and the effect of electric stimulation on cell proliferation].

    Science.gov (United States)

    Podcherniaeva, R Ia; Suetina, I A; Mikhaĭlova, G R; Lopatina, O A; Bobrinetskiĭ, I I; Morozov, R A; Seleznev, A S

    2012-01-01

    It was demonstrated that the three studied samples of carbon nanotubes of domestic production fixed on the substrate surface did not have toxic effect and could be used for cell cultivation. A biocompatible conductive coating based on carbon nanotubes and bovine serum albumin was developed. The efficacy of the coating for growing in vitro cell cultures was tested. A device was developed for electric stimulation of the cells. Local electric potential was applied to the cells using nanoscale electrodes. The results of human embryonic fibroblast cultivation in a pulsed electric field on conductive nanocomposite substrates were presented. An 26% increase in the proliferative activity of cells was observed at potentials up to 100 mV.

  10. Injection of duck recombinant follistatin fusion protein into duck muscle tissues stimulates satellite cell proliferation and muscle fiber hypertrophy.

    Science.gov (United States)

    Liu, He-he; Wang, Ji-wen; Yu, Hai-yue; Zhang, Rong-ping; Chen, Xi; Jin, Hai-bo; Dai, Fei; Li, Liang; Xu, Feng

    2012-06-01

    Follistatin (FST) can inhibit the expression of myostatin, which is a predominant inhibitor of muscle development. The potential application of myostatin-based technology has been prompted in different ways in agriculture. We previously constructed an expression vector of duck FST and isolated the FST fusion protein. After the protein was purified and refolded, it was added to the medium of duck myoblasts cultured in vitro. The results show that the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide value of the myoblasts in the duck FST treatment group is higher than that in the control group, which indicates that the duck FST fusion protein exhibits the biological activities that can accelerate myoblast proliferation. To further investigate the roles of duck FST on muscle development, we injected the protein into the duck muscle tissues in vivo. The results show that both the duck muscle fiber cross-sectional area and the satellite cell activation frequency are influenced more in the FST treatment group than they are in the control group. In addition to these phenomena, expression of MyoD and Myf5 were increased, and the expression of myostatin was decreased. Together, these results suggest the potential for using duck FST fusion protein to inhibit myostatin activity and subsequently to enhance muscle growth in vivo. The mechanism by which FST regulates muscle development in the duck is similar to that in mammals and fishes.

  11. The Water Fraction of Calendula officinalis Hydroethanol Extract Stimulates In Vitro and In Vivo Proliferation of Dermal Fibroblasts in Wound Healing.

    Science.gov (United States)

    Dinda, Manikarna; Mazumdar, Swagata; Das, Saurabh; Ganguly, Durba; Dasgupta, Uma B; Dutta, Ananya; Jana, Kuladip; Karmakar, Parimal

    2016-10-01

    The active fraction and/or compounds of Calendula officinalis responsible for wound healing are not known yet. In this work we studied the molecular target of C. officinalis hydroethanol extract (CEE) and its active fraction (water fraction of hydroethanol extract, WCEE) on primary human dermal fibroblasts (HDF). In vivo, CEE or WCEE were topically applied on excisional wounds of BALB/c mice and the rate of wound contraction and immunohistological studies were carried out. We found that CEE and only its WCEE significantly stimulated the proliferation as well as the migration of HDF cells. Also they up-regulate the expression of connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA) in vitro. In vivo, CEE or WCEE treated mice groups showed faster wound healing and increased expression of CTGF and α-SMA compared to placebo control group. The increased expression of both the proteins during granulation phase of wound repair demonstrated the potential role of C. officinalis in wound healing. In addition, HPLC-ESI MS analysis of the active water fraction revealed the presence of two major compounds, rutin and quercetin-3-O-glucoside. Thus, our results showed that C. officinalis potentiated wound healing by stimulating the expression of CTGF and α-SMA and further we identified active compounds. Copyright © 2016 John Wiley & Sons, Ltd.

  12. The role of macrophage migration inhibitory factor in mast cell-stimulated fibroblast proliferation and collagen production.

    Science.gov (United States)

    Ningyan, Gu; Xu, Yao; Hongfei, Shi; Jingjing, Chen; Min, Chen

    2015-01-01

    Current clinical and translational studies have shown that mast cell plays a pivotal role in multiple fibrotic diseases including scleroderma. However, the lack of mature human mast cell culture model exhibits a major obstacle for further dissection of cytokines and signaling molecules required for mast cell mediated fibrosis in various diseases. Macrophage Migration Inhibitory Factor is a mast cell released pro-inflammatory cytokine which is deregulated in scleroderma patients and is also involved in non-scleroderma related fibrosis. In the current study, we successfully generated a practical and reliable human mast cell culture system with bone marrow CD34+ hematopietic precursors. The derivative mast cell is normal in terms of both morphology and function as manifested by normal degranulation. More importantly, we were able to show mast cell conditioned medium as well as MIF supplementation augments fibroblast proliferation and collagen synthesis. This positive regulatory effect of mast cell conditioned medium can be dampened by MIF antibody. In addition, MIF-knockdown significantly inhibits pro-fibrotic activities of CD34+ hematopietic precursor derived mast cells. These data strongly suggest that mast cell released MIF is required for mast cell mediated fibrogenic activities. The current manuscript seems to be the first mechanistic report showing the significance of MIF in mast cell mediated fibrosis, which may pave the way for the development of potential MIF-targeted therapy for fibrotic diseases to a further extent. Moreover, we strongly believe mast cell culture and differentiation model as well as corresponding genetic manipulation methodology will be helpful in characterizing novel mast cell based therapeutic targets.

  13. Amniotic Membrane Modifies the Genetic Program Induced by TGFß, Stimulating Keratinocyte Proliferation and Migration in Chronic Wounds.

    Directory of Open Access Journals (Sweden)

    Antonia Alcaraz

    Full Text Available Post-traumatic large-surface or deep wounds often cannot progress to reepithelialisation because they become irresponsive in the inflammatory stage, so intervention is necessary to provide the final sealing epidermis. Previously we have shown that Amniotic Membrane (AM induced a robust epithelialisation in deep traumatic wounds.To better understand this phenomenon, we used keratinocytes to investigate the effect of AM on chronic wounds. Using keratinocytes, we saw that AM treatment is able to exert an attenuating effect upon Smad2 and Smad3 TGFß-induced phosphorylation while triggering the activation of several MAPK signalling pathways, including ERK and JNK1, 2. This also has a consequence for TGFß-induced regulation on cell cycle control key players CDK1A (p21 and CDK2B (p15. The study of a wider set of TGFß regulated genes showed that the effect of AM was not wide but very concrete for some genes. TGFß exerted a powerful cell cycle arrest; the presence of AM however prevented TGFß-induced cell cycle arrest. Moreover, AM induced a powerful cell migration response that correlates well with the expression of c-Jun protein at the border of the healing assay. Consistently, the treatment with AM of human chronic wounds induced a robust expression of c-Jun at the wound border.The effect of AM on the modulation of TGFß responses in keratinocytes that favours proliferation together with AM-induced keratinocyte migration is the perfect match that allows chronic wounds to move on from their non-healing state and progress into epithelialization. Our results may explain why the application of AM on chronic wounds is able to promote epithelialisation.

  14. RAC1b overexpression stimulates proliferation and NF-kB-mediated anti-apoptotic signaling in thyroid cancer cells

    Science.gov (United States)

    Faria, Márcia; Matos, Paulo; Pereira, Teresa; Cabrera, Rafael; Cardoso, Bruno A.; Bugalho, Maria João

    2017-01-01

    Overexpression of tumor-associated RAC1b has been recently highlighted as one of the most promising targets for therapeutic intervention in colon, breast, lung and pancreatic cancer. RAC1b is a hyperactive variant of the small GTPase RAC1 and has been recently shown to be overexpressed in a subset of papillary thyroid carcinomas associated with unfavorable outcome. Using the K1 PTC derived cell line as an in vitro model, we observed that both RAC1 and RAC1b were able to induce a significant increase on NF-kB and cyclin D1 reporter activity. A clear p65 nuclear localization was found in cells transfected with RAC1b-WT, confirming NF-kB canonical pathway activation. Consistently, we observed a RAC1b-mediated decrease in IκBα (NF-kB inhibitor) protein levels. Moreover, we show that RAC1b overexpression stimulates G1/S progression and protects thyroid cells against induced apoptosis, the latter through a process involving the NF-kB pathway. Present data support previous findings suggesting an important role for RAC1b in the development of follicular cell-derived thyroid malignancies and point out NF-kB activation as one of the molecular mechanisms associated with the pro-tumorigenic advantage of RAC1b overexpression in thyroid carcinomas. PMID:28234980

  15. The antioxidant N-acetylcysteine prevents HIF-1 stabilization under hypoxia in vitro but does not affect tumorigenesis in multiple breast cancer models in vivo.

    Directory of Open Access Journals (Sweden)

    Jaclyn Sceneay

    Full Text Available Intratumoral hypoxia is a poor prognostic factor associated with reduced disease-free survival in many cancer types, including breast cancer. Hypoxia encourages tumor cell proliferation, stimulates angiogenesis and lymphangiogenesis, and promotes epithelial-mesenchymal transition and metastasis. Tumor cells respond to a hypoxic state by stabilizing the Hif-1α subunit of the Hypoxia-Inducible Factor (HIF transcription factor to promote expression of various tumor- and metastasis-promoting hypoxic response genes. The antioxidant N-acetylcysteine (NAC was recently shown to prevent Hif-1α stabilization under hypoxia, and has been identified as a potential alternative method to target the hypoxic response in tumors. We utilized three orthotopic syngeneic murine models of breast cancer, the PyMT, EO771 and 4T1.2 models, to investigate the ability of NAC to modulate the hypoxic response in vitro and in vivo. While NAC prevented Hif-1α stabilization under hypoxia in vitro and increased levels of glutathione in the blood of mice in vivo, this did not translate to a difference in tumor growth or the hypoxic state of the tumor compared to untreated control mice. In addition, NAC treatment actually increased metastatic burden in an experimental metastasis model. This work raises questions regarding the validity of NAC as an anti-tumorigenic agent in breast cancer, and highlights the need to further investigate its properties in vivo in different cancer models.

  16. Pheochromocytomas: the (pseudo)-hypoxia hypothesis.

    Science.gov (United States)

    Favier, Judith; Gimenez-Roqueplo, Anne-Paule

    2010-12-01

    Hypoxia and pheochromocytoma/paraganglioma have a long common history. Since the description, almost 40 years ago, of an increased incidence of head and neck paragangliomas in chronic hypoxia, discoveries on oxygen-sensing and on hereditary paraganglioma in the beginning of years 2000 provided the proof of concept of a strong link between these neuroendocrine tumors and the hypoxic pathway. It was demonstrated that both SDH and VHL genes mutations lead to the abnormal stabilization and activation of hypoxia-inducible factors, and to the subsequent regulation of multiple target genes, the products of which are implicated in proliferation, apoptosis, angiogenesis, energy metabolism or invasiveness and metastases. Altogether, physiological, genetic, cellular and molecular data collected over years all point to a central role of the hypoxic or pseudohypoxic pathway in pheochromocytoma and paraganglioma tumorigenesis. 2010 Elsevier Ltd. All rights reserved.

  17. Cannabidiol stimulates Aml-1a-dependent glial differentiation and inhibits glioma stem-like cells proliferation by inducing autophagy in a TRPV2-dependent manner.

    Science.gov (United States)

    Nabissi, Massimo; Morelli, Maria Beatrice; Amantini, Consuelo; Liberati, Sonia; Santoni, Matteo; Ricci-Vitiani, Lucia; Pallini, Roberto; Santoni, Giorgio

    2015-10-15

    Glioma stem-like cells (GSCs) correspond to a tumor cell subpopulation, involved in glioblastoma multiforme (GBM) tumor initiation and acquired chemoresistance. Currently, drug-induced differentiation is considered as a promising approach to eradicate this tumor-driving cell population. Recently, the effect of cannabinoids (CBs) in promoting glial differentiation and inhibiting gliomagenesis has been evidenced. Herein, we demonstrated that cannabidiol (CBD) by activating transient receptor potential vanilloid-2 (TRPV2) triggers GSCs differentiation activating the autophagic process and inhibits GSCs proliferation and clonogenic capability. Above all, CBD and carmustine (BCNU) in combination overcome the high resistance of GSCs to BCNU treatment, by inducing apoptotic cell death. Acute myeloid leukemia (Aml-1) transcription factors play a pivotal role in GBM proliferation and differentiation and it is known that Aml-1 control the expression of several nociceptive receptors. So, we evaluated the expression levels of Aml-1 spliced variants (Aml-1a, b and c) in GSCs and during their differentiation. We found that Aml-1a is upregulated during GSCs differentiation, and its downregulation restores a stem cell phenotype in differentiated GSCs. Since it was demonstrated that CBD induces also TRPV2 expression and that TRPV2 is involved in GSCs differentiation, we evaluated if Aml-1a interacted directly with TRPV2 promoters. Herein, we found that Aml-1a binds TRPV2 promoters and that Aml-1a expression is upregulated by CBD treatment, in a TRPV2 and PI3K/AKT dependent manner. Altogether, these results support a novel mechanism by which CBD inducing TRPV2-dependent autophagic process stimulates Aml-1a-dependent GSCs differentiation, abrogating the BCNU chemoresistance in GSCs.

  18. Hypoxia and oxygenation induce a metabolic switch between pentose phosphate pathway and glycolysis in glioma stem-like cells.

    Science.gov (United States)

    Kathagen, Annegret; Schulte, Alexander; Balcke, Gerd; Phillips, Heidi S; Martens, Tobias; Matschke, Jakob; Günther, Hauke S; Soriano, Robert; Modrusan, Zora; Sandmann, Thomas; Kuhl, Carsten; Tissier, Alain; Holz, Mareike; Krawinkel, Lutz A; Glatzel, Markus; Westphal, Manfred; Lamszus, Katrin

    2013-11-01

    Fluctuations in oxygen tension during tissue remodeling impose a major metabolic challenge in human tumors. Stem-like tumor cells in glioblastoma, the most common malignant brain tumor, possess extraordinary metabolic flexibility, enabling them to initiate growth even under non-permissive conditions. We identified a reciprocal metabolic switch between the pentose phosphate pathway (PPP) and glycolysis in glioblastoma stem-like (GS) cells. Expression of PPP enzymes is upregulated by acute oxygenation but downregulated by hypoxia, whereas glycolysis enzymes, particularly those of the preparatory phase, are regulated inversely. Glucose flux through the PPP is reduced under hypoxia in favor of flux through glycolysis. PPP enzyme expression is elevated in human glioblastomas compared to normal brain, especially in highly proliferative tumor regions, whereas expression of parallel preparatory phase glycolysis enzymes is reduced in glioblastomas, except for strong upregulation in severely hypoxic regions. Hypoxia stimulates GS cell migration but reduces proliferation, whereas oxygenation has opposite effects, linking the metabolic switch to the "go or grow" potential of the cells. Our findings extend Warburg's observation that tumor cells predominantly utilize glycolysis for energy production, by suggesting that PPP activity is elevated in rapidly proliferating tumor cells but suppressed by acute severe hypoxic stress, favoring glycolysis and migration to protect cells against hypoxic cell damage.

  19. Arginine, leucine, and glutamine stimulate proliferation of porcine trophectoderm cells through the MTOR-RPS6K-RPS6-EIF4EBP1 signal transduction pathway.

    Science.gov (United States)

    Kim, Jinyoung; Song, Gwonhwa; Wu, Guoyao; Gao, Haijun; Johnson, Gregory A; Bazer, Fuller W

    2013-05-01

    During the peri-implantation and early placentation periods in pigs, conceptuses (embryo and its extra-embryonic membranes) undergo dramatic morphological changes and differentiation that require the exchange of nutrients (histotroph) and gasses across the trophectoderm and a true epitheliochorial placenta. Of these nutrients, arginine (Arg), leucine (Leu), and glutamine (Gln) are essential components of histotroph; however, little is known about changes in their total amounts in the uterine lumen of cyclic and pregnant gilts and their effects on cell signaling cascades. Therefore, we determined quantities of Arg, Leu, and Gln in uterine luminal fluids and found that total recoverable amounts of these amino acids increased in pregnant but not cyclic gilts between Days 12 and 15 after onset of estrus. We hypothesized that Arg, Leu, and Gln have differential effects on hypertrophy, hyperplasia, and differentiated functions of trophectoderm cells that are critical to conceptus development. Primary porcine trophectoderm (pTr) cells treated with either Arg, Leu, or Gln had increased abundance of phosphorylated RPS6K, RPS6, and EIF4EBP1 compared to basal levels, and this effect was maintained for up to 120 min. When pTr cells were treated with Arg, Leu, and Gln, low levels of pRPS6K and pEIF4EBP1 were detected in the cytosol, but the abundance of nuclear pRPS6K increased. Immunofluorescence analyses revealed abundant amounts of pRPS6 protein in the cytoplasm of pTr cells treated with Arg, Leu, and Gln. These amino acids also increased proliferation of pTr cells. Furthermore, when Arg, Leu, and Gln were combined with siRNAs for either MTOR, RPTOR, or RICTOR, effects of those amino acids on proliferation of pTr cells were significantly inhibited. Collectively, these results indicate that Arg, Leu, and Gln act coordinately to stimulate proliferation of pTr cells through activation of the MTOR-RPS6K-RPS6-EIF4EBP1 signal transduction pathway.

  20. Migraine induced by hypoxia

    DEFF Research Database (Denmark)

    Arngrim, Nanna; Schytz, Henrik Winther; Britze, Josefine

    2016-01-01

    Migraine with aura is prevalent in high-altitude populations suggesting an association between migraine aura and hypoxia. We investigated whether experimental hypoxia triggers migraine and aura attacks in patients suffering from migraine with aura. We also investigated the metabolic and vascular...... response to hypoxia. In a randomized double-blind crossover study design, 15 migraine with aura patients were exposed to 180 min of normobaric hypoxia (capillary oxygen saturation 70-75%) or sham on two separate days and 14 healthy controls were exposed to hypoxia. Glutamate and lactate concentrations...... in the visual cortex were measured by proton magnetic resonance spectroscopy. The circumference of cranial arteries was measured by 3 T high-resolution magnetic resonance angiography. Hypoxia induced migraine-like attacks in eight patients compared to one patient after sham (P = 0.039), aura in three...

  1. The Ca2+-calmodulin-dependent kinase II is activated in papillary thyroid carcinoma (PTC) and mediates cell proliferation stimulated by RET/PTC.

    Science.gov (United States)

    Rusciano, Maria Rosaria; Salzano, Marcella; Monaco, Sara; Sapio, Maria Rosaria; Illario, Maddalena; De Falco, Valentina; Santoro, Massimo; Campiglia, Pietro; Pastore, Lucio; Fenzi, Gianfranco; Rossi, Guido; Vitale, Mario

    2010-03-01

    RET/papillary thyroid carcinoma (PTC), TRK-T, or activating mutations of Ras and BRaf are frequent genetic alterations in PTC, all leading to the activation of the extracellular-regulated kinase (Erk) cascade. The aim of this study was to investigate the role of calmodulin-dependent kinase II (CaMKII) in the signal transduction leading to Erk activation in PTC cells. In normal thyroid cells, CaMKII and Erk were in the inactive form in the absence of stimulation. In primary PTC cultures and in PTC cell lines harboring the oncogenes RET/PTC-1 or BRaf(V600E), CaMKII was active also in the absence of any stimulation. Inhibition of calmodulin or phospholipase C (PLC) attenuated the level of CaMKII activation. Expression of recombinant RET/PTC-3, BRaf(V600E), or Ras(V12) induced CaMKII activation. Inhibition of CaMKII attenuated Erk activation and DNA synthesis in thyroid papillary carcinoma (TPC-1), a cell line harboring RET/PTC-1, suggesting that CaMKII is a component of the Erk signal cascade in this cell line. In conclusion, PTCs contain an active PLC/Ca(2+)/calmodulin-dependent signal inducing constitutive activation of CaMKII. This kinase is activated by BRaf(V600E), oncogenic Ras, and by RET/PTC. CaMKII participates to the activation of the Erk pathway by oncogenic Ras and RET/PTC and contributes to their signal output, thus modulating tumor cell proliferation.

  2. TCDD induces the hypoxia-inducible factor (HIF)-1α regulatory pathway in human trophoblastic JAR cells.

    Science.gov (United States)

    Liao, Tien-Ling; Chen, Su-Chee; Tzeng, Chii-Reuy; Kao, Shu-Huei

    2014-09-30

    The exposure to dioxin can compromise pregnancy outcomes and increase the risk of preterm births. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been demonstrated to induce placental hypoxia at the end of pregnancy in a rat model, and hypoxia has been suggested to be the cause of abnormal trophoblast differentiation and placental insufficiency syndromes. In this study, we demonstrate that the non-hypoxic stimulation of human trophoblastic cells by TCDD strongly increased hypoxia inducible factor-1 alpha (HIF-1α) stabilization. TCDD exposure induced the generation of reactive oxygen species (ROS) and nitric oxide. TCDD-induced HIF-1α stabilization and Akt phosphorylation was inhibited by pretreatment with wortmannin (a phosphatidylinositol 3-kinase (PI3K) inhibitor) or N-acetylcysteine (a ROS scavenger). The augmented HIF-1α stabilization by TCDD occurred via the ROS-dependent activation of the PI3K/Akt pathway. Additionally, a significant increase in invasion and metallomatrix protease-9 activity was found in TCDD-treated cells. The gene expression of vascular endothelial growth factor and placental growth factor was induced upon TCDD stimulation, whereas the protein levels of peroxisome proliferator-activated receptor γ (PPARγ), PPARγ coactivator-1α, mitochondrial transcription factor, and uncoupling protein 2 were decreased. Our results indicate that an activated HIF-1α pathway, elicited oxidative stress, and induced metabolic stress contribute to TCDD-induced trophoblastic toxicity. These findings may provide molecular insight into the TCDD-induced impairment of trophoblast function and placental development.

  3. Selective vulnerability in brain hypoxia

    DEFF Research Database (Denmark)

    Cervos-Navarro, J.; Diemer, Nils Henrik

    1991-01-01

    Neuropathology, selective vulnerability, brain hypoxia, vascular factors, excitotoxicity, ion homeostasis......Neuropathology, selective vulnerability, brain hypoxia, vascular factors, excitotoxicity, ion homeostasis...

  4. 低氧处理对不同年龄C57小鼠骨髓间充质干细胞增殖能力的影响%Effects of hypoxia on the proliferation of bone marrow mesenchymal stem cells isolated from C57 mice of different age

    Institute of Scientific and Technical Information of China (English)

    张振中; 刘南波; 刘煜凡; 李基伟; 付小兵; 吴旭

    2015-01-01

    目的::探讨低氧处理对不同年龄 C57小鼠骨髓间充质干细胞(BMSCs)增殖的影响。方法:全骨髓法从3~6周年轻C57小鼠(年轻组)股骨和胫骨的骨髓中提取、分离 BMSCs,传代至第6代,部分于37℃、5%CO2条件下中常规培养,连续5 d观察细胞的形态及数目,绘制细胞生长曲线;部分细胞进行成骨和成脂诱导。另取第6代BMSCs,随机分为低氧处理组(37℃、5%O2条件下培养30 min,再常规培养)和阴性对照组(不行低氧处理,仅常规培养),常规培养8h后固定细胞,结晶紫染色。观察两组细胞处理前后的数量变化。全骨髓法提取18~24个月老龄C57小鼠(老龄组)的骨髓细胞常规培养,连续12 d 观察细胞的形态及数目并绘制细胞生长曲线。将老龄组C57小鼠的骨髓贴壁细胞分为低氧处理组和阴性对照组,处理方法同年轻小鼠低氧处理和阴性对照组,于常规培养24 h后固定细胞,结晶紫染色,观察两组细胞处理前后的数量变化。结果:年轻 C57小鼠 BM-SCs 增殖能力强,可传代至第6代,经过5 d的培养细胞数量逐渐增加,并具有成骨、成脂诱导分化能力;但经低氧处理后,BMSCs呈片状脱落。老龄C57小鼠的骨髓贴壁细胞增殖能力差,经过12 d 的原代培养,细胞数量逐渐减少,并且只有一个集落形成;经低氧处理,贴壁细胞数量锐减,无新的集落形成。结论:低氧处理不能在体外扩增阶段提高C57小鼠BMSCs的增殖能力。%Objective:To investigate the effects of hypoxia on the proliferation of bone marrow mesenchymal stem cells (BMSCs)isolated from C5 7 mice of different age. Methods:BMSCs were isolated from the marrow of femurs and tibias of young C5 7 mice aged 3 to 6 weeks (young group)by whole bone marrow adherence method, and they were cultured. The 6th generation of BMSCs were routinely cultured under the condition of 5% CO2 and 37 ℃,their potential of differentiation to osteocytes and

  5. Hypoxia and brain development

    NARCIS (Netherlands)

    Nyakas, Csaba; Buwalda, Bauke; Luiten, P.

    1996-01-01

    Hypoxia threatens brain function during the entire life-span starting from early fetal age up to senescence. This review compares the short-term, long-term and life-spanning effects of fetal chronic hypoxia and neonatal anoxia on several behavioural paradigms including novelty-induced spontaneous an

  6. Steroid Hormones and Antihormones can Reverse the Castration Induced Stimulation of the Pineal and Adrenal Karyomorphology and Cell Proliferation in Mice (Mus musculus

    Directory of Open Access Journals (Sweden)

    S. Chakraborty

    2011-01-01

    Full Text Available In the present investigation, influence of castration and castrated animals supplemented with steroid hormones and antihormones on pineal-adrenal karyomorphology and dynamics were studied in post pubertal male mice. A group of thirty five mice were orchidectomized and (N = 7 sham operated, were kept in laboratory condition for 30 days. Such castrated were separately supplemented with estradiol at a dose of 5 g, testosterone at a dose of 100 g and antihormones, tamoxifen at a dose of 500 g and flutamide at 2 g daily (all at doses per 100 g.b.w. for ten consecutive days following thirty days of post castration. Present data reveal that both pineal and adrenal gland nuclear size and cell proliferation were significantly increased in thirty days post orchidectomized mice compared to control animals. The values are control pinealocyte nuclear diameter (dim: 4.750.06; castrated pinealocyte nuclear diameter (m: 5.340.04 (p<0.001. Control pineal M% 1.250.07; castrated pineal M% 2.020.11 (p<0.001. In control adrenal, representative of zones was Z. fasciculata nuclear diameter (m (5.110.04; castrated Z. fasciculata nuclear diameter (m 5.410.03 (p<0.001. Control adrenal M% (1.030.06 castrated adrenal M% (1.630.09 p<0.001. It was further observed that such pineal and adrenal stimulation in orchidectomized mice were significantly decreased when orchidectomized mice were administered with steroid hormones (estradiol and testosterone and antihormones (tamoxifen and flutamide compared to orchidectomized mice. Our study indicates that there exists a mutual stimulatory relationship between pineal and adrenal under conditions of steroid deprivation. However, exogenous administration of steroid hormones and antihormones to those castrated mice caused inhibition of these two peripheral endocrine glands.

  7. Daidzein stimulates osteogenesis facilitating proliferation, differentiation, and antiapoptosis in human osteoblast-like MG-63 cells via estrogen receptor-dependent MEK/ERK and PI3K/Akt activation.

    Science.gov (United States)

    Jin, Xin; Sun, Jing; Yu, Bo; Wang, Yue; Sun, Wei Jia; Yang, Jing; Huang, Su Hui; Xie, Wen Li

    2017-06-01

    Daidzein, a natural soy isoflavone, has a structure similar to estradiol and exhibiting bone-sparing effects against osteoporosis. However, the molecular mechanisms of osteogenesis remain unclear. We hypothesized that daidzein stimulates osteogenesis through estrogen receptor (ER)-dependent signal pathways. To test this hypothesis, we investigated the effects of daidzein compared with 17β-estradiol on proliferation, differentiation, and cisplatin-induced apoptosis in human osteoblast-like MG-63 cells containing 2 ER isoforms. The results showed that daidzein stimulated cell proliferation by altering cell cycle distribution, promoted cell differentiation by increasing the alkaline phosphatase activity and collagen content, and reduced cell apoptosis associated by up-regulating the expression of Bcl-xL. The above actions of daidzein were prevented by cotreatment with the ER antagonist ICI 182780. Using small interfering RNA technology, we further demonstrated that the effects of daidzein on alkaline phosphatase activity, collagen content, and cell apoptosis are mediated by both ERα and ERβ, whereas the effects on cell proliferation are primarily mediated by ERα. However, the effects of 17β-estradiol on osteoblastic proliferation and survival are mediated by both ER isotypes, and the effects on osteoblastic differentiation are primarily mediated by ERα. The use of specific inhibitors indicated that activation of the mitogen-activated protein kinase kinase/extracellular regulated kinase (MEK/ERK) and phosphoinositide 3-kinase/protein kinase B or PKB (PI3K/Akt) signaling pathway at least partially accounts for these effects of daidzein. Taken together, the results indicate that daidzein stimulates osteogenesis through facilitating proliferation, differentiation, and antiapoptosis in human osteoblast-like MG-63 cells via activation of MEK/ERK and PI3K/Akt in an ER-dependent manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Stimulation of neoplastic mouse lung cell proliferation by alveolar macrophage-derived, insulin-like growth factor-1 can be blocked by inhibiting MEK and PI3K activation

    Directory of Open Access Journals (Sweden)

    Malkinson Alvin M

    2011-06-01

    Full Text Available Abstract Background Worldwide, lung cancer kills more people than breast, colon and prostate cancer combined. Alterations in macrophage number and function during lung tumorigenesis suggest that these immune effector cells stimulate lung cancer growth. Evidence from cancer models in other tissues suggests that cancer cells actively recruit growth factor-producing macrophages through a reciprocal signaling pathway. While the levels of lung macrophages increase during tumor progression in mouse models of lung cancer, and high pulmonary macrophage content correlates with a poor prognosis in human non-small cell lung cancer, the specific role of alveolar macrophages in lung tumorigenesis is not clear. Methods After culturing either an immortalized lung macrophage cell line or primary murine alveolar macrophages from naïve and lung-tumor bearing mice with primary tumor isolates and immortalized cell lines, the effects on epithelial proliferation and cellular kinase activation were determined. Insulin-like growth factor-1 (IGF-1 was quantified by ELISA, and macrophage conditioned media IGF-1 levels manipulated by IL-4 treatment, immuno-depletion and siRNA transfection. Results Primary macrophages from both naïve and lung-tumor bearing mice stimulated epithelial cell proliferation. The lungs of tumor-bearing mice contained 3.5-times more IGF-1 than naïve littermates, and media conditioned by freshly isolated tumor-educated macrophages contained more IGF-1 than media conditioned by naïve macrophages; IL-4 stimulated IGF-1 production by both macrophage subsets. The ability of macrophage conditioned media to stimulate neoplastic proliferation correlated with media IGF-1 levels, and recombinant IGF-1 alone was sufficient to induce epithelial proliferation in all cell lines evaluated. Macrophage-conditioned media and IGF-1 stimulated lung tumor cell growth in an additive manner, while EGF had no effect. Macrophage-derived factors increased p-Erk1/2, p

  9. Effect of vitamin E on cerebral cortical oxidative stress and brain-derived neurotrophic factor gene expression induced by hypoxia and exercise in rats.

    Science.gov (United States)

    Sakr, H F; Abbas, A M; El Samanoudy, A Z

    2015-04-01

    Brain-derived neurotrophic factor (BDNF) is involved in the proliferation of neurons, and its expression increases significantly with exercise. We aimed to investigate the effects of chronic exercise (swimming) and sustained hypoxia on cortical BDNF expression in both the presence and absence of vitamin E. Sixty four male Sprague-Dawley rats were divided into two equal groups; a normoxic group and a hypoxic group. Both groups were equally subdivided into four subgroups: sedentary, sedentary with vitamin E, chronic exercise either with or without vitamin E supplementation. Arterial PO(2), and the levels of cortical malondialdehyde (MDA), antioxidants (reduced glutathione GSH, superoxide dismutase (SOD), catalase (CAT) and vitamin E) and BDNF gene expression were investigated. Hypoxia significantly increased MDA production and BDNF gene expression and decreased the antioxidants compared to control rats. Chronic exercise in hypoxic and normoxic rats increased MDA level and BDNF gene expression and decreased the antioxidants. Providing vitamin E supplementation to the hypoxic and normoxic rats significantly reduced MDA and BDNF gene expression and increased antioxidants. We conclude that sustained hypoxia and chronic exercise increased BDNF gene expression and induced oxidative stress. Moreover, vitamin E attenuated the oxidative stress and decreased BDNF gene expression in sustained hypoxia and chronic exercise which confirms the oxidative stress-induced stimulation of BDNF gene expression.

  10. Plasmid DNA as a special stimular to stimulate lymphocyte proliferation%DNA作为一种特异性刺激剂刺激淋巴细胞增殖的研究

    Institute of Scientific and Technical Information of China (English)

    吴琼; 孙英军; 张艳; 郑海学

    2011-01-01

    目的 为了探讨质粒DNA体外刺激淋巴细胞的增殖状况,建立了一种方便可靠的评价豚鼠细胞免疫水平的试验方法.方法 用羧基荧光素乙酰乙酸琥珀酰亚胺酯(cFsEl染色豚鼠全血,经植物血凝素(PHA)和质粒DNA刺激培养,利用流式细胞术分析细胞的增殖状况.结果 豚鼠全血经PHA和DNA刺激,淋巴细胞增殖能力不同;未免疫组经DNA和PHA刺激后增殖的差异显著,免疫组差异不显著.DNA质粒在体内外均可作为刺激源刺激淋巴细胞增殖.结论 建立了一种基于活细胞染料CFSE染色的豚鼠全血淋巴细胞增殖试验方法,可方便、快速、有效地评价细胞免疫水平.%To investigate the level of lymphocyte proliferation stimulated by plasmid DNA in vitro, and to establish a convenient and reliable method to assess the level of cellular immunity in guinea pig, the whole blood of guinea pig was stained by Carboxyfluorescein diacetate succinimidyl ester (CFSE), then stimulated by phytohemagglutinin(PHA) and plasmid DNA, and cultivated for 3 days.The cell proliferation was detected by flow cytometry.We observed that PHA and DNA stimulation could promote lymphocyte proliferation: the proliferation in non-immune group was significantly enhanced, while the inactivated vaccine immune group did not significantly changed, which indicate that plasmid DNA can be used as animmunogen to stimulate lymphocyte proliferation.Through this study, a live cell-based dye CFSE staining of guinea pig whole blood lymphocyte proliferation test method was established to evaluate the cellular immunity conveniently and effectively.

  11. 氧化苦参碱对小鼠淋巴结T细胞增殖的双向作用%Two-ways effects of Oxymatrine on T lymphocyte proliferation in mouse lymph node stimulated by Con A

    Institute of Scientific and Technical Information of China (English)

    伍斌; 谢红付; 李罗丝; 张江林; 李建国

    2006-01-01

    [Objective] To investigate the effects of Oxymatrine (OMT) on mouse lymphocyte proliferation stimulated by Con A, explore the mechanism of the effects of OMT on the immune system and provide theoretical and experimental evidence for the clinical application of OMT in treating immune-related diseases. [Methods] CFDA-SE staining and flow cytometry were used to detect the fluorescence intensity of lymphocytes after stimulated by polyclonal stimulators Con A and OMT. Related softwares were used to analyze the effects of OMT on mouse lymphocyte proliferation. [Results] OMT has the function to restrain the proliferation of lymphocyte of mouse depended on its concentration with 500, 125 and 31 μg/mL in substrate, but 16, 8, 4, 2 μg/mL concentration, it improves the proliferation of T lymphocytes of mouse's lymph node, the dependence on its concentration is not significant. [Conclusions ] 1. Both CFDA-SE dyeing and flow cytometer were reliable tools to analyze lymphocyte proliferation. 2. OMT has the two-ways effects on T lymphocyte proliferation in mouse lymph node stimulated by Con A.%目的检测氧化苦参碱(Oxymatrine,OMT)对刀豆蛋白A(Con A)刺激的小鼠淋巴结T细胞增殖的影响,探讨OMT对免疫系统的作用机制,为临床用OMT治疗免疫相关性疾病提供理论和实验依据.方法利用CFDA-SE染色,流式细胞术检测淋巴细胞在多克隆刺激剂Con A和OMT的共同作同下荧光强度的变化,并应用CELLQuest软件分析OMT对小鼠淋巴结T细胞增殖的影响程度.结果 500、125和31μg/mLOMT对小鼠淋巴结T细胞增殖呈剂量依赖性抑制,而16、8、4、2μg/mL OMT对小鼠淋巴结T细胞增殖起促进作用,但其剂量依赖关系不明显.结论 CFDA-SE染色和流式细胞术是分析淋巴细胞增殖的有力工具:OMT对小鼠淋巴结T细胞的增殖呈双向作用.

  12. Aortic endothelial cells regulate proliferation of human monocytes in vitro via a mechanism synergistic with macrophage colony-stimulating factor. Convergence at the cyclin E/p27(Kip1) regulatory checkpoint.

    Science.gov (United States)

    Antonov, A S; Munn, D H; Kolodgie, F D; Virmani, R; Gerrity, R G

    1997-06-15

    Monocyte-derived macrophages (Mphis) are pivotal participants in the pathogenesis of atherosclerosis. Evidence from both animal and human plaques indicates that local proliferation may contribute to accumulation of lesion Mphis, and the major Mphi growth factor, macrophage colony stimulating factor (MCSF), is present in atherosclerotic plaques. However, most in vitro studies have failed to demonstrate that human monocytes/Mphis possess significant proliferative capacity. We now report that, although human monocytes cultured in isolation showed only limited MCSF-induced proliferation, monocytes cocultured with aortic endothelial cells at identical MCSF concentrations underwent enhanced (up to 40-fold) and prolonged (21 d) proliferation. In contrast with monocytes in isolation, this was optimal at low seeding densities, required endothelial cell contact, and could not be reproduced by coculture with smooth muscle cells. Intimal Mphi isolated from human aortas likewise showed endothelial cell contact-dependent, MCSF-induced proliferation. Consistent with a two-signal mechanism governing Mphi proliferation, the cell cycle regulatory protein, cyclin E, was rapidly upregulated by endothelial cell contact in an MCSFindependent fashion, but MCSF was required for successful downregulation of the cell cycle inhibitory protein p27(Kip1) before cell cycling. Thus endothelial cells and MCSF differentially and synergistically regulate two Mphi genes critical for progression through the cell cycle.

  13. Hypoxia- or PDGF-BB-dependent paxillin tyrosine phosphorylation in pulmonary hypertension is reversed by HIF-1α depletion or imatinib treatment.

    Science.gov (United States)

    Veith, C; Zakrzewicz, D; Dahal, B K; Bálint, Z; Murmann, K; Wygrecka, M; Seeger, W; Schermuly, R T; Weissmann, N; Kwapiszewska, G

    2014-12-01

    Chronic exposure to hypoxia induces a pronounced remodelling of the pulmonary vasculature leading to pulmonary hypertension (PH). The remodelling process also entails increased proliferation and decreased apoptosis of pulmonary arterial smooth muscle cells (PASMC), processes regulated by the cytoskeletal protein paxillin. In this study, we aimed to examine the molecular mechanisms leading to deregulation of paxillin in PH. We detected a time-dependent increase in paxillin tyrosine 31 (Y31) and 118 (Y118) phosphorylation following hypoxic exposure (1 % O2) or platelet-derived growth factor (PDGF)-BB stimulation of primary human PASMC. In addition, both, hypoxia- and PDGF-BB increased the nuclear localisation of phospho-paxillin Y31 as indicated by immunofluorescence staining in human PASMC. Elevated paxillin tyrosine phosphorylation in human PASMC was attenuated by hypoxia-inducible factor (HIF)-1α depletion or by treatment with the PDGF-BB receptor antagonist, imatinib. Moreover, we observed elevated paxillin Y31 and Y118 phosphorylation in the pulmonary vasculature of chronic hypoxic mice (21 days, 10 % O2) which was reversible by imatinib-treatment. PDGF-BB-dependent PASMC proliferation was regulated via the paxillin-Erk1/2-cyclin D1 pathway. In conclusion, we suggest paxillin up-regulation and phosphorylation as an important mechanism of vascular remodelling underlying pulmonary hypertension.

  14. VEGF-A/NRP1 stimulates GIPC1 and Syx complex formation to promote RhoA activation and proliferation in skin cancer cells

    Directory of Open Access Journals (Sweden)

    Ayumi Yoshida

    2015-09-01

    Full Text Available Neuropilin-1 (NRP1 has been identified as a VEGF-A receptor. DJM-1, a human skin cancer cell line, expresses endogenous VEGF-A and NRP1. In the present study, the RNA interference of VEGF-A or NRP1 suppressed DJM-1 cell proliferation. Furthermore, the overexpression of the NRP1 wild type restored shNRP1-treated DJM-1 cell proliferation, whereas NRP1 cytoplasmic deletion mutants did not. A co-immunoprecipitation analysis revealed that VEGF-A induced interactions between NRP1 and GIPC1, a scaffold protein, and complex formation between GIPC1 and Syx, a RhoGEF. The knockdown of GIPC1 or Syx reduced active RhoA and DJM-1 cell proliferation without affecting the MAPK or Akt pathway. C3 exoenzyme or Y27632 inhibited the VEGF-A-induced proliferation of DJM-1 cells. Conversely, the overexpression of the constitutively active form of RhoA restored the proliferation of siVEGF-A-treated DJM-1 cells. Furthermore, the inhibition of VEGF-A/NRP1 signaling upregulated p27, a CDK inhibitor. A cell-penetrating oligopeptide that targeted GIPC1/Syx complex formation inhibited the VEGF-A-induced activation of RhoA and suppressed DJM-1 cell proliferation. In conclusion, this new signaling pathway of VEGF-A/NRP1 induced cancer cell proliferation by forming a GIPC1/Syx complex that activated RhoA to degrade the p27 protein.

  15. Rapamycin inhibits BAFF-stimulated cell proliferation and survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells.

    Science.gov (United States)

    Zeng, Qingyu; Zhang, Hai; Qin, Jiamin; Xu, Zhigang; Gui, Lin; Liu, Beibei; Liu, Chunxiao; Xu, Chong; Liu, Wen; Zhang, Shuangquan; Huang, Shile; Chen, Long

    2015-12-01

    B-cell activating factor (BAFF) is involved in not only physiology of normal B cells, but also pathophysiology of aggressive B cells related to malignant and autoimmune diseases. Rapamycin, a lipophilic macrolide antibiotic, has recently shown to be effective in the treatment of human lupus erythematosus. However, how rapamycin inhibits BAFF-stimulated B-cell proliferation and survival has not been fully elucidated. Here, we show that rapamycin inhibited human soluble BAFF (hsBAFF)-induced cell proliferation and survival in normal and B-lymphoid (Raji and Daudi) cells by activation of PP2A and inactivation of Erk1/2. Pretreatment with PD98059, down-regulation of Erk1/2, expression of dominant negative MKK1, or overexpression of wild-type PP2A potentiated rapamycin's suppression of hsBAFF-activated Erk1/2 and B-cell proliferation/viability, whereas expression of constitutively active MKK1, inhibition of PP2A by okadaic acid, or expression of dominant negative PP2A attenuated the inhibitory effects of rapamycin. Furthermore, expression of a rapamycin-resistant and kinase-active mTOR (mTOR-T), but not a rapamycin-resistant and kinase-dead mTOR-T (mTOR-TE), conferred resistance to rapamycin's effects on PP2A, Erk1/2 and B-cell proliferation/viability, implying mTOR-dependent mechanism involved. The findings indicate that rapamycin inhibits BAFF-stimulated cell proliferation/survival by targeting mTOR-mediated PP2A-Erk1/2 signaling pathway in normal and neoplastic B-lymphoid cells. Our data highlight that rapamycin may be exploited for preventing excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.

  16. Hypoxia inducible factors 1 and 2 are important transcriptional effectors in primary macrophages experiencing hypoxia

    Science.gov (United States)

    Fang, Hsin-Yu; Hughes, Russell; Murdoch, Craig; Coffelt, Seth; Biswas, Subhra K.; Harris, Adrian L.; Johnson, Randall S.; Imityaz, Hongxia Z.; Simon, M. Celeste; Fredlund, Erik; Greten, Florian; Rius, Jordi; Lewis, Claire E.

    2010-01-01

    Ischemia exists in many diseased tissues including arthritic joints, atherosclerotic plaques and malignant tumors. Macrophages accumulate in these sites and upregulate hypoxia-inducible transcription factors (HIFs) 1 and 2 in response to the hypoxia present. Here we show that the gene expression profile in primary human and murine macrophages changes markedly when they are exposed to hypoxia for 18h. For example, they were seen to upregulate the cell surface receptors, CXCR4 and GLUT1, and the potent, tumor-promoting cytokines, VEGFA, interleukins 1β and 8, adrenomedullin, CXCR4 and angiopoietin-2. Hypoxia also stimulated their expression and/or phosphorylation of various proteins in the NF-κB signalling pathway. We then used both genetic and pharmacological methods to manipulate the levels of HIFs 1α and 2α or NF-κB in primary macrophages in order to elucidate their role in the hypoxic induction of many of these key genes. These studies showed that both HIFs 1 and 2, but not NF-κB, are important transcriptional effectors regulating the responses of macrophages to such a period of hypoxia. Further studies using experimental mouse models are now warranted to investigate the role of such macrophage responses in the progression of various diseased tissues like malignant tumors. PMID:19454749

  17. β-Adrenergic signaling in rat heart is similarly affected by continuous and intermittent normobaric hypoxia.

    Science.gov (United States)

    Hahnova, Klara; Kasparova, Dita; Zurmanova, Jitka; Neckar, Jan; Kolar, Frantisek; Novotny, Jiri

    2016-04-01

    Chronic hypoxia may produce a cardioprotective phenotype characterized by increased resistance to ischemia-reperfusion injury. Nevertheless, the molecular basis of cardioprotective effects of hypoxia is still not quite clear. The present study investigated the consequences of a 3-week adaptation to cardioprotective (CNH, continuous normobaric hypoxia) and nonprotective (INH, intermittent normobaric hypoxia; 23 h/day hypoxia followed by 1 h/day reoxygenation) regimen of hypoxia on β-adrenergic signaling in the rat myocardium. Both regimens of hypoxia lowered body weight and led to marked right ventricular (RV) hypertrophy, which was accompanied by 25% loss of β1-adrenergic receptors (β1-ARs) in the RV. No significant changes were found in β-ARs in left ventricular (LV) preparations from animals adapted to hypoxia. Although adenylyl cyclase (AC) activity stimulated through the G proteins was decreased in the RV and increased in the LV after exposure to hypoxia, there were no significant changes in the expression of the dominant myocardial AC 5/6 isoforms and the stimulatory G proteins. These data suggest that chronic normobaric hypoxia may strongly affect myocardial β-adrenergic signaling but adaptation to cardioprotective and nonprotective regimens of hypoxia does not cause notably diverse changes.

  18. Differential Contribution of the Guanylyl Cyclase-Cyclic GMP-Protein Kinase G Pathway to the Proliferation of Neural Stem Cells Stimulated by Nitric Oxide

    Directory of Open Access Journals (Sweden)

    Bruno P. Carreira

    2012-02-01

    Full Text Available Nitric oxide (NO is an important inflammatory mediator involved in the initial boost in the proliferation of neural stem cells following brain injury. However, the mechanisms underlying the proliferative effect of NO are still unclear. The aim of this work was to investigate whether cyclic GMP (cGMP and the cGMP-dependent kinase (PKG are involved in the proliferative effect triggered by NO in neural stem cells. For this purpose, cultures of neural stem cells isolated from the mouse subventricular zone (SVZ were used. We observed that long-term exposure to the NO donor (24 h, NOC-18, increased the proliferation of SVZ cells in a cGMP-dependent manner, since the guanylate cyclase inhibitor, ODQ, prevented cell proliferation. Similarly to NOC-18, the cGMP analogue, 8-Br-cGMP, also increased cell proliferation. Interestingly, shorter exposures to NO (6 h increased cell proliferation in a cGMP-independent manner via the ERK/MAP kinase pathway. The selective inhibitor of PKG, KT5823, prevented the proliferative effect induced by NO at 24 h but not at 6 h. In conclusion, the proliferative effect of NO is initially mediated by the ERK/MAPK pathway, and at later stages by the GC/cGMP/PKG pathway. Thus, our work shows that NO induces neural stem cell proliferation by targeting these two pathways in a biphasic manner.

  19. Identifying novel hypoxia-associated markers of chemoresistance in ovarian cancer.

    LENUS (Irish Health Repository)

    McEvoy, Lynda M

    2015-01-01

    Ovarian cancer is associated with poor long-term survival due to late diagnosis and development of chemoresistance. Tumour hypoxia is associated with many features of tumour aggressiveness including increased cellular proliferation, inhibition of apoptosis, increased invasion and metastasis, and chemoresistance, mostly mediated through hypoxia-inducible factor (HIF)-1α. While HIF-1α has been associated with platinum resistance in a variety of cancers, including ovarian, relatively little is known about the importance of the duration of hypoxia. Similarly, the gene pathways activated in ovarian cancer which cause chemoresistance as a result of hypoxia are poorly understood. This study aimed to firstly investigate the effect of hypoxia duration on resistance to cisplatin in an ovarian cancer chemoresistance cell line model and to identify genes whose expression was associated with hypoxia-induced chemoresistance.

  20. Fibrocyte-like cells from intrauterine growth restriction placentas have a reduced ability to stimulate angiogenesis.

    Science.gov (United States)

    Riddell, Meghan R; Winkler-Lowen, Bonnie; Jiang, Yanyan; Guilbert, Larry J; Davidge, Sandra T

    2013-09-01

    Intrauterine growth restriction (IUGR) is a common complication of pregnancy whereby the fetus fails to achieve its genetic growth potential. Malformation of the placental vasculature is observed in IUGR and may be due to the development of the placenta in a chronically hypoxic environment. Recently, we identified that the predominant stromal cells in the angiogenic zones of the placenta are fibrocyte-like cells. The conditioned medium from fibrocyte-like cells (FcCM) has been shown to stimulate angiogenesis in vitro. Thus, we hypothesized that FcCM from IUGR cells would have a reduced ability to stimulate angiogenesis and that chronic hypoxia would decrease the ability of both normal and IUGR fibrocyte-like cells to stimulate angiogenesis. IUGR FcCM had a reduced ability to stimulate endothelial tubule-like structure formation and an increased ability to stimulate endothelial migration compared with normal FcCM. However, normal and IUGR FcCM produced in chronic hypoxia did not alter endothelial proliferation, migration, or tubule-like structure formation. IUGR FcCM was found to have reduced levels of the pro-angiogenic cytokine IL-8 and increased levels of the anti-angiogenic factors activin-A and pigment epithelium-derived growth factor. Thus, alterations in the ability of IUGR fibrocyte-like cells to stimulate angiogenesis may contribute to the development of vascular malformation in IUGR, but in vitro these changes cannot be attributed to a chronically hypoxic environment.

  1. Effects of Mechanical Stimulation on Proliferation and Differentiation in MG-63 Osteoblast-like Cells%力学刺激对MG-63成骨样细胞增殖分化的影响

    Institute of Scientific and Technical Information of China (English)

    杨敏; 黄凌云; 肖立伟; 廖二元

    2012-01-01

    This paper is aimed to explore the effects oi mechanical stimulation on proliferation and differentiation of osteoblasts. Cultured MG-63 osteoblast-like cells were strained by the four-point bending cell mechanics loader. In the study, we observed the effects of different magnitudes and duration of mechanical strain on the markers of proliferation and differentiation in osteoblasts. The protein levels and Alkaline phosphatase (ALP) activity were determined by western blot and a-nitrophenyl phosphate assay respectively. The mineralization nodules were stained using Alizarin Red-S method. We found: (1) the expression of proliferating cell nuclear antigen (PCNA), ALP activity in strained group were significantly increased compared to those in the control group, but the role did not increase with the increase of the magnitude of the stimulation; and (2) under appropriate stimulation (2000μstrain), the expression of PCNA, COL I protein and ALP activity increased gradually with the increase of loading time, and appropriate stimulation promoted the formation of mineralization nodules. It indicated that appropriate mechanical stimulation could promote proliferation and differentiation of osteoblasts.%为探讨力学刺激对成骨细胞增殖分化的影响,应用根据四点弯曲原理设计的加力装置对MG-63成骨样细胞进行力学刺激,观察不同大小和作用时间的机械应变对成骨细胞增殖分化的影响.本研究中蛋白表达、碱性磷酸酶(ALP)活性测定分别采用Western blot、α-磷酸奈酚法,采用茜素红染色观察矿化结节的形成.结果发现:(1)与对照组相比,加力组增殖细胞核抗原(PCNA)蛋白表达、ALP活性均明显增加,但这种作用并不随着力刺激大小的增加而增加.(2)在适宜的力刺激(2000 μstrain)下,随着加力时间的增加,PCNA、Ⅰ型胶原(COLⅠ)蛋白表达及ALP活性逐渐增加,并且适宜的力刺激也促进了矿化结节的形成.该结果提示适宜的力学

  2. The consumption of n-3 polyunsaturated fatty acids differentially modulates gene expression of peroxisome proliferator-activated receptor alpha and gamma and hypoxia-inducible factor 1 alpha in subcutaneous adipose tissue of obese adolescents.

    Science.gov (United States)

    Mejía-Barradas, César M; Del-Río-Navarro, Blanca E; Domínguez-López, Aarón; Campos-Rodríguez, Rafael; Martínez-Godínez, María de-Los-Á; Rojas-Hernández, Saúl; Lara-Padilla, Eleazar; Abarca-Rojano, Edgar; Miliar-García, Ángel

    2014-02-01

    The aim of this study was to evaluate the effect of long-chain omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on metabolic state and gene expression in subcutaneous adipose tissues of obese adolescents. Obese adolescents (n = 26, 10 girls and 16 boys) aged 12.4 ± 2.1 years were assigned to a 12-week regimen of n-3 PUFA intake. Five times per day, subjects received a food supplement consisting of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (3 g per day, 944 mg EPA, and 2,088 mg DHA). Blood parameters were measured, and subcutaneous adipose tissue biopsies were analyzed to determine gene expression at baseline and after 12 weeks. Student's t test and the Wilcoxon signed-rank test were used to estimate differences in arithmetic means of pre- and post-dietary supplementation for various anthropometric, biochemical, clinical, and gene expression parameters. After 12 weeks, n-3 PUFA consumption was associated with decreased body mass index (29.7 ± 4.6 vs. 27.8 ± 4.4 kg/m(2); P Fatty acid supplementation/n3 PUFA supplementation was associated with a downregulated expression of the genes encoding PPARγ and PGC-1α (P consumption and dietary restriction improved the anthropometric parameters and decreased the triglycerides levels of the adolescents, suggesting a reduction in hypoxia in subcutaneous adipose tissue.

  3. Low oxygen level increases proliferation and metabolic changes in bovine granulosa cells.

    Science.gov (United States)

    Shiratsuki, Shogo; Hara, Tomotaka; Munakata, Yasuhisa; Shirasuna, Koumei; Kuwayama, Takehito; Iwata, Hisataka

    2016-12-05

    The present study addresses molecular backgrounds underlying low oxygen induced metabolic changes and 1.2-fold change in bovine granulosa cell (GCs) proliferation. RNA-seq revealed that low oxygen (5%) upregulated genes associated with HIF-1 and glycolysis and downregulated genes associated with mitochondrial respiration than that in high oxygen level (21%). Low oxygen level induced high glycolytic activity and low mitochondrial function and biogenesis. Low oxygen level enhanced GC proliferation with high expression levels of HIF-1, VEGF, AKT, mTOR, and S6RP, whereas addition of anti-VEGF antibody decreased cellular proliferation with low phosphorylated AKT and mTOR expression levels. Low oxygen level reduced SIRT1, whereas activation of SIRT1 by resveratrol increased mitochondrial replication and decreased cellular proliferation with reduction of phosphorylated mTOR. These results suggest that low oxygen level stimulates the HIF1-VEGF-AKT-mTOR pathway and up-regulates glycolysis, which contributes to GC proliferation, and downregulation of SIRT1 contributes to hypoxia-associated reduction of mitochondria and cellular proliferation.

  4. Hypoxia-mediated metastasis.

    Science.gov (United States)

    Chang, Joan; Erler, Janine

    2014-01-01

    Metastasis is responsible for more than 90 % of deaths among cancer patient. It is a highly complex process that involves the interplay between cancer cells, the tumor microenvironment, and even noncancerous host cells. Metastasis can be seen as a step-wise process: acquisition of malignant phenotype, invasion into surrounding tissue, intravasation into blood vessels, survival in circulation, extravasation to distant sites, and colonization of new organs. Before the actual metastatic process, the secondary site is also prepared for the arrival of the cancer cells through formation of "premetastatic niches." Hypoxia (low oxygen tension) is commonly found in solid tumors more than a few millimeters cubed and often is associated with a poor prognosis. Hypoxia increases angiogenesis, cancer cell survival, and metastasis. This chapter described how hypoxia regulates each step of the metastatic process and how blocking hypoxia-driven metastasis through targeting hypoxia-inducible factor 1, or downstream effector molecules such as the lysyl oxidase family may represent highly effective preventive strategies against metastasis in cancer patients.

  5. Local tissue hypoxia and formation of nasal polyps

    Institute of Scientific and Technical Information of China (English)

    姜舒; 董震; 朱冬冬; 杨占泉

    2003-01-01

    Objective To explore the response of nasal mucosa epithelial cells to hypoxia in terms of formation of nasal polyps (NP). Methods Epithelial cells of NP and inferior turbinate (IT) were cultured serum-fr ee under normal oxygen and hypoxic circumstances with stimulation of IL-1β and TNFα. The vascular endothelial growth factor (VEGF)mRNA and VEGF protein leve ls of the cultured cells were detected using in situ hybridization and ELISA, re spectively. Results The expression of VEGF mRNA was significantly higher in epithelial cells of NP t han in IT exposed to pro-inflammatory cytokines or hypoxia (P<0.01). VEGF levels were higher in NP epithelial cells than those of IT (P<0.01) under hypoxia.Conclusion VEGF-induced by hypoxia is very important for the early stages of forming polyps.

  6. Gefitinib circumvents hypoxia-induced drug resistance by the modulation of HIF-1alpha.

    Science.gov (United States)

    Rho, Jin Kyung; Choi, Yun Jung; Lee, Jin Kyung; Ryoo, Baek-Yeol; Na, Im Ii; Yang, Sung Hyun; Kim, Cheol Hyeon; Yoo, Young Do; Lee, Jae Cheol

    2009-03-01

    Hypoxia-inducible factor-1alpha (HIF-1alpha) is a transcriptional factor which is activated by hypoxia and associated with cell survival, proliferation and drug resistance. Recent studies have shown that the down-stream molecules of the epidermal growth factor receptor (EGFR) signal are involved in the hypoxia-dependent or -independent HIF-1alpha protein accumulation. Thus, we hypothesized that an EGFR-TK inhibitor, gefitinib, might circumvent the hypoxia-induced drug resistance via the regulation of HIF-1alpha expression. In our data, treatment of gefitinib suppressed induced HIF-1alpha by hypoxia. This action of gefitinib was caused by reduced protein stability without any change in the level of HIF-1alpha mRNA. The effect of gefitinib on down-regulation of HIF-1alpha was reversed by transfection of constitutively active form of Akt. The cellular response to gefitinib was similar in both normoxia and hypoxia condition. However, the response to conventional chemotherapeutic drugs decreased >50% under hypoxia condition and they did not change HIF-1alpha expression. In addition, the suppression of HIF-1alpha using siRNA overcame partially hypoxia-induced drug resistance. In conclusion, gefitinib was able to circumvent hypoxia-induced drug resistance suggesting that the effective suppression of HIF-1alpha by the inhibition of EGFR-Akt pathway may overcome the hypoxia-induced drug resistance.

  7. Stimulation of Naive Monocytes and PBMCs with Coagulation Proteases Results in Thrombin-Mediated and PAR-1-Dependent Cytokine Release and Cell Proliferation in PBMCs Only

    NARCIS (Netherlands)

    Nieuwenhuizen, L.; Falkenburg, W. J. J.; Schutgens, R. E. G.; Roosendaal, G.; van Veghel, K.; Biesma, D. H.; Lafeber, F. P. J. G.

    2013-01-01

    Protease-activated receptors (PARs) are stimulated by proteolytic cleavage of their extracellular domain. Coagulation proteases, such as FVIIa, the binary TF-FVIIa complex, free FXa, the ternary TF-FVIIa-FXa complex and thrombin, are able to stimulate PARs. Whereas the role of PARs on platelets is w

  8. Stimulation of AIDS lymphocytes with calcium ionophore (A23187) and phorbol ester (PMA): studies of cytoplasmic free Ca, IL-2 receptor expression, IL-2 production, and proliferation

    DEFF Research Database (Denmark)

    Hofmann, B; Moller, J; Langhoff, E

    1989-01-01

    nine patients with AIDS with the response of lymphocytes from nine control subjects showed that the response of AIDS lymphocytes was severely decreased when stimulated with PHA and no further response could be achieved by stimulation with A23187/PMA. On the other hand, no significant difference between...... the PHA-induced rise of cytoplasmic free calcium concentration ([Ca2+]1) in normal and AIDS lymphocytes was observed. The percentage of cells expressing IL-2 receptors (CD25) was also normal both after addition of PHA and after addition of A23187/PMA and the expression was normal on both CD4 and CD8 cells....... The production of IL-2 in normal lymphocytes stimulated with A23187/PMA was 33 times higher than that after stimulation with PHA. In AIDS lymphocytes the production of IL-2 induced by all activators was severely decreased compared to control subjects, although the production of IL-2 after stimulation with A23187...

  9. Development of a chemically defined in vitro culture system to effectively stimulate the proliferation of adult human dermal fibroblasts.

    Science.gov (United States)

    Kim, Min Seong; Yun, Jung Im; Gong, Seung Pyo; Ahn, Ji Yeon; Lim, Jeong Mook; Song, Young Han; Park, Kyu Hyun; Lee, Seung Tae

    2015-07-01

    Despite the fact that dermal fibroblasts are a practical model for research related to cell physiology and cell therapy, an in vitro culture system excluding serum, which complicates standardization and specificity and induces variability and unwanted effects, does not exist. We tried to establish a CDCS that supports effective proliferation of aHDFs. KDMEM supplemented with 5% (v/v) KSR, 12 ng/ml bFGF, 5 ng/ml EGF and 1 μg/ml hydrocortisone supported sufficient proliferation of aHDFs for 1 week. However, aHDF proliferation was decreased greatly after subculture. This problem could be overcome by culturing aHDFs in CDCM in culture plates coated with 10 μg/ml FN. Long-term culture of aHDFs was achieved using CDCM and FN-coated culture plates for 7 weeks. The optimized CDCS increased the proliferation of aHDFs significantly, without any increase in the senescence rate or alteration in morphology of aHDFs, despite long-term culture. In conclusion, we established a CDCS that improved proliferation of aHDFs while inhibiting cellular senescence. The CDCS will contribute to advances in various future research related to clinical skin regeneration.

  10. Chemoreceptors and cardiovascular control in acute and chronic systemic hypoxia

    Directory of Open Access Journals (Sweden)

    J.M. Marshall

    1998-07-01

    Full Text Available This review describes the ways in which the primary bradycardia and peripheral vasoconstriction evoked by selective stimulation of peripheral chemoreceptors can be modified by the secondary effects of a chemoreceptor-induced increase in ventilation. The evidence that strong stimulation of peripheral chemoreceptors can evoke the behavioural and cardiovascular components of the alerting or defence response which is characteristically evoked by novel or noxious stimuli is considered. The functional significance of all these influences in systemic hypoxia is then discussed with emphasis on the fact that these reflex changes can be overcome by the local effects of hypoxia: central neural hypoxia depresses ventilation, hypoxia acting on the heart causes bradycardia and local hypoxia of skeletal muscle and brain induces vasodilatation. Further, it is proposed that these local influences can become interdependent, so generating a positive feedback loop that may explain sudden infant death syndrome (SIDS. It is also argued that a major contributor to these local influences is adenosine. The role of adenosine in determining the distribution of O2 in skeletal muscle microcirculation in hypoxia is discussed, together with its possible cellular mechanisms of action. Finally, evidence is presented that in chronic systemic hypoxia, the reflex vasoconstrictor influences of the sympathetic nervous system are reduced and/or the local dilator influences of hypoxia are enhanced. In vitro and in vivo findings suggest this is partly explained by upregulation of nitric oxide (NO synthesis by the vascular endothelium which facilitates vasodilatation induced by adenosine and other NO-dependent dilators and attenuates noradrenaline-evoked vasoconstriction.

  11. Inhibition of Hypoxia-Induced Cell Motility by p16 in MDA-MB-231 Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Liyuan Li, Yi Lu

    2010-01-01

    Full Text Available Our previous studies indicated that p16 suppresses breast cancer angiogenesis and metastasis, and downregulates VEGF gene expression by neutralizing the transactivation of the VEGF transcriptional factor HIF-1α. Hypoxia stimulates tumor malignant progression and induces HIF-1α. Because p16 neutralizes effect of HIF-1α and attenuates tumor metastatic progression, we intended to investigate whether p16 directly affects one or more aspects of the malignant process such as adhesion and migration of breast cancer cells. To approach this aim, MDA-MB-231 and other breast cancer cells stably transfected with Tet-on inducible p16 were used to study the p16 effect on growth, adhesion and migration of the cancer cells. We found that p16 inhibits breast cancer cell proliferation and migration, but has no apparent effect on cell adhesion. Importantly, p16 inhibits hypoxia-induced cell migration in breast cancer in parallel with its inhibition of HIF-1α transactivation activity. This study suggests that p16's ability to suppress tumor metastasis may be partially resulted from p16's inhibition on cell migration, in addition to its known functions on inhibition of cell proliferation, angiogenesis and induction of apoptosis.

  12. Vasoinhibins Prevent Bradykinin-Stimulated Endothelial Cell Proliferation by Inactivating eNOS via Reduction of both Intracellular Ca2+ Levels and eNOS Phosphorylation at Ser1179

    Directory of Open Access Journals (Sweden)

    Carmen Clapp

    2011-07-01

    Full Text Available Vasoinhibins, a family of antiangiogenic peptides derived from prolactin proteolysis, inhibit the vascular effects of several proangiogenic factors, including bradykinin (BK. Here, we report that vasoinhibins block the BK-induced proliferation of bovine umbilical vein endothelial cells. This effect is mediated by the inactivation of endothelial nitric oxide synthase (eNOS, as the NO donor DETA-NONOate reverted vasoinhibin action. It is an experimentally proven fact that the elevation of intracellular Ca2+ levels ([Ca2+]i upon BK stimulation activates eNOS, and vasoinhibins blocked the BK-mediated activation of phospholipase C and the formation of inositol 1,4,5-triphosphate leading to a reduced release of Ca2+ from intracellular stores. The [Ca2+]i rise evoked by BK also involves the influx of extracellular Ca2+ via canonical transient receptor potential (TRPC channels. Vasoinhibins likely interfere with TRPC-mediated Ca2+ entry since La3+, which is an enhancer of TRPC4 and TRPC5 channel activity, prevented vasoinhibins from blocking the stimulation by BK of endothelial cell NO production and proliferation, and vasoinhibins reduced the BK-induced increase of TRPC5 mRNA expression. Finally, vasoinhibins prevented the BK-induced phosphorylation of eNOS at Ser1179, a post-translational modification that facilitates Ca2+-calmodulin activation of eNOS. Together, our data show that vasoinhibins, by lowering NO production through the inhibition of both [Ca2+]i mobilization and eNOS phosphorylation, prevent the BK-induced stimulation of endothelial cell proliferation. Thus, vasoinhibins help to regulate BK effects on angiogenesis and vascular homeostasis.

  13. Vasoinhibins Prevent Bradykinin-Stimulated Endothelial Cell Proliferation by Inactivating eNOS via Reduction of both Intracellular Ca2+ Levels and eNOS Phosphorylation at Ser1179

    Science.gov (United States)

    Thebault, Stéphanie; González, Carmen; García, Celina; Zamarripa, David Arredondo; Nava, Gabriel; Vaca, Luis; López-Casillas, Fernando; de la Escalera, Gonzalo Martínez; Clapp, Carmen

    2011-01-01

    Vasoinhibins, a family of antiangiogenic peptides derived from prolactin proteolysis, inhibit the vascular effects of several proangiogenic factors, including bradykinin (BK). Here, we report that vasoinhibins block the BK-induced proliferation of bovine umbilical vein endothelial cells. This effect is mediated by the inactivation of endothelial nitric oxide synthase (eNOS), as the NO donor DETA-NONOate reverted vasoinhibin action. It is an experimentally proven fact that the elevation of intracellular Ca2+ levels ([Ca2+]i) upon BK stimulation activates eNOS, and vasoinhibins blocked the BK-mediated activation of phospholipase C and the formation of inositol 1,4,5-triphosphate leading to a reduced release of Ca2+ from intracellular stores. The [Ca2+]i rise evoked by BK also involves the influx of extracellular Ca2+ via canonical transient receptor potential (TRPC) channels. Vasoinhibins likely interfere with TRPC-mediated Ca2+ entry since La3+, which is an enhancer of TRPC4 and TRPC5 channel activity, prevented vasoinhibins from blocking the stimulation by BK of endothelial cell NO production and proliferation, and vasoinhibins reduced the BK-induced increase of TRPC5 mRNA expression. Finally, vasoinhibins prevented the BK-induced phosphorylation of eNOS at Ser1179, a post-translational modification that facilitates Ca2+-calmodulin activation of eNOS. Together, our data show that vasoinhibins, by lowering NO production through the inhibition of both [Ca2+]i mobilization and eNOS phosphorylation, prevent the BK-induced stimulation of endothelial cell proliferation. Thus, vasoinhibins help to regulate BK effects on angiogenesis and vascular homeostasis.

  14. Ell3 stimulates proliferation, drug resistance, and cancer stem cell properties of breast cancer cells via a MEK/ERK-dependent signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hee-Jin [Department of Biomedical Science, College of Life Science, CHA University, Seoul (Korea, Republic of); Kim, Gwangil [Department of Pathology, CHA Bundang Medical Center, CHA University, Seoul (Korea, Republic of); Park, Kyung-Soon, E-mail: kspark@cha.ac.kr [Department of Biomedical Science, College of Life Science, CHA University, Seoul (Korea, Republic of)

    2013-08-09

    Highlights: •Ell3 enhances proliferation and drug resistance of breast cancer cell lines. •Ell3 is related to the cancer stem cell characteristics of breast cancer cell lines. •Ell3 enhances oncogenicity of breast cancer through the ERK1/2 signaling pathway. -- Abstract: Ell3 is a RNA polymerase II transcription elongation factor that is enriched in testis. The C-terminal domain of Ell3 shows strong similarities to that of Ell (eleven−nineteen lysine-rich leukemia gene), which acts as a negative regulator of p53 and regulates cell proliferation and survival. Recent studies in our laboratory showed that Ell3 induces the differentiation of mouse embryonic stem cells by protecting differentiating cells from apoptosis via the promotion of p53 degradation. In this study, we evaluated the function of Ell3 in breast cancer cell lines. MCF-7 cell lines overexpressing Ell3 were used to examine cell proliferation and cancer stem cell properties. Ectopic expression of Ell3 in breast cancer cell lines induces proliferation and 5-FU resistance. In addition, Ell3 expression increases the cancer stem cell population, which is characterized by CD44 (+) or ALDH1 (+) cells. Mammosphere-forming potential and migration ability were also increased upon Ell3 expression in breast cancer cell lines. Through biochemical and molecular biological analyses, we showed that Ell3 regulates proliferation, cancer stem cell properties and drug resistance in breast cancer cell lines partly through the MEK−extracellular signal-regulated kinase signaling pathway. Murine xenograft experiments showed that Ell3 expression promotes tumorigenesis in vivo. These results suggest that Ell3 may play a critical role in promoting oncogenesis in breast cancer by regulating cell proliferation and cancer stem cell properties via the ERK1/2 signaling pathway.

  15. Clonal analysis of proliferation and differentiation of paired daughter cells: action of granulocyte-macrophage colony-stimulating factor on granulocyte-macrophage precursors.

    OpenAIRE

    Metcalf, D.

    1980-01-01

    Mouse granulocyte-macrophage progenitor cells were stimulated to divide by the granulocyte-macrophage colony-stimulating factor (GM-CSF). The two daughter cells were separated; one daughter was transferred to medium containing a high concentration of GM-CSF, the other to medium containing a low concentration. Daughter cell-derived clones in the presence of 2500 units of GM-CSF had average cell cycle times 3.5 +/- 2.5 (SEM) hr shorter than clones derived from the paired daughter cell stimulate...

  16. Carotid body oxygen sensing and adaptation to hypoxia.

    Science.gov (United States)

    López-Barneo, José; Macías, David; Platero-Luengo, Aida; Ortega-Sáenz, Patricia; Pardal, Ricardo

    2016-01-01

    The carotid body (CB) is the principal arterial chemoreceptor that mediates the hyperventilatory response to hypoxia. Our understanding of CB function and its role in disease mechanisms has progressed considerably in the last decades, particularly in recent years. The sensory elements of the CB are the neuron-like glomus cells, which contain numerous transmitters and form synapses with afferent sensory fibers. The activation of glomus cells under hypoxia mainly depends on the modulation of O2-sensitive K(+) channels which leads to cell depolarization and the opening of Ca(2+) channels. This model of sensory transduction operates in all mammalian species studied thus far, including man. However, the molecular mechanisms underlying the modulation of ion channel function by changes in the O2 level are as yet unknown. The CB plays a fundamental role in acclimatization to sustained hypoxia. Mice with CB atrophy or patients who have undergone CB resection due to surgical treatments show a marked intolerance to even mild hypoxia. CB growth under hypoxia is supported by the existence of a resident population of neural crest-derived stem cells of glia-like phenotype. These stem cells are not highly affected by exposure to low O2 tension; however, there are abundant synapse-like contacts between the glomus cells and stem cells (chemoproliferative synapses), which may be needed to trigger progenitor cell proliferation and differentiation under hypoxia. CB hypo- or hyper-activation may also contribute to the pathogenesis of several prevalent human diseases.

  17. Mesenchymal Stem Cells Respond to Hypoxia by Increasing Diacylglycerols.

    Science.gov (United States)

    Lakatos, Kinga; Kalomoiris, Stefanos; Merkely, Béla; Nolta, Jan A; Fierro, Fernando A

    2016-02-01

    Mesenchymal stem cells (MSC) are currently being tested clinically for a plethora of conditions, with most approaches relying on the secretion of paracrine signals by MSC to modulate the immune system, promote wound healing, and induce angiogenesis. Hypoxia has been shown to affect MSC proliferation, differentiation, survival and secretory profile. Here, we investigate changes in the lipid composition of human bone marrow-derived MSC after exposure to hypoxia. Using mass spectrometry, we compared the lipid profiles of MSC derived from five different donors, cultured for two days in either normoxia (control) or hypoxia (1% oxygen). Hypoxia induced a significant increase of total triglycerides, fatty acids and diacylglycerols (DG). Remarkably, reduction of DG levels using the phosphatidylcholine-specific phospholipase C inhibitor D609 inhibited the secretion of VEGF and Angiopoietin-2, but increased the secretion of interleukin-8, without affecting significantly their respective mRNA levels. Functionally, incubation of MSC in hypoxia with D609 inhibited the potential of the cells to promote migration of human endothelial cells in a wound/scratch assay. Hence, we show that hypoxia induces in MSC an increase of DG that may affect the angiogenic potential of these cells.

  18. Effects of dextromethorphan on glial cell function: proliferation, maturation, and protection from cytotoxic molecules.

    Science.gov (United States)

    Lisak, Robert P; Nedelkoska, Liljana; Benjamins, Joyce A

    2014-05-01

    Dextromethorphan (DM), a sigma receptor agonist and NMDA receptor antagonist, protects neurons from glutamate excitotoxicity, hypoxia and ischemia, and inhibits microglial activation, but its effects on differentiation and protection of cells in the oligodendroglial lineage are unknown. It is important to protect oligodendroglia (OL) to prevent demyelination and preserve axons, and to protect oligodendroglial progenitors (OPC) to optimize myelination during development and remyelination following damage. Enriched glial cultures from newborn rat brain were used 1-2 days or 6-8 days after shakeoff for OPC or mature OL. DM had large effects on glial proliferation in less mature cultures in contrast to small variable effects in mature cultures; 1 μM DM stimulated proliferation of OPC by 4-fold, microglia (MG) by 2.5-fold and astroglia (AS) by 2-fold. In agreement with increased OPC proliferation, treatment of OPC with DM for 3 days increased the % of OPC relative to OL, with a smaller difference by 5 days, suggesting that maturation of OPC to OL was "catching up" by 5 days. DM at 2 and 20 μM protected both OL and OPC from killing by glutamate as well as NMDA, AMPA, quinolinic acid, staurosporine, and reactive oxygen species (ROS). DM did not protect against kynurenic acid, and only modestly against NO. These agents and DM were not toxic to AS or MG at the concentrations used. Thus, DM stimulates proliferation of OPC, and protects both OL and OPC against excitotoxic and inflammatory insults.

  19. Fibroblast growth factor-1 is a mesenchymal stromal cell-secreted factor stimulating proliferation of osteoarthritic chondrocytes in co-culture

    NARCIS (Netherlands)

    Wu, Ling; Leijten, Jeroen; Blitterswijk, van Clemens A.; Karperien, Marcel

    2013-01-01

    Previously, we showed that mesenchymal stromal cells (MSCs) in co-culture with primary chondrocytes secrete soluble factors that increase chondrocyte proliferation. The objective of this study is to identify these factors. Human primary chondrocytes (hPCs) isolated from late-stage osteoarthritis pat

  20. Salidroside exerts protective effects against chronic hypoxia-induced pulmonary arterial hypertension via AMPKα1-dependent pathways.

    Science.gov (United States)

    Chen, Mayun; Cai, Hui; Yu, Chang; Wu, Peiliang; Fu, Yangyang; Xu, Xiaomei; Fan, Rong; Xu, Cunlai; Chen, Yanfan; Wang, Liangxing; Huang, Xiaoying

    2016-01-01

    Salidroside, an active ingredient isolated from Rhodiola rosea, has shown to exert protective effects against chronic hypoxia-induced pulmonary arterial hypertension (PAH). However, the underlying mechanisms were not well known. Based on our recent reports, we predicted the involvement of adenosine monophosphate-activated protein kinase (AMPK) mediated effects in salidroside regulation of PAH. Firstly, to prove the hypothesis, rats were exposed to chronic hypoxia and treated with increasing concentrations of salidroside or a selective AMPK activator-5'-aminoimidazole-4-carboxamide ribonucleoside (AICAR) for 4 weeks. After salidroside or AICAR treatment, the chronic hypoxia-induced right ventricular hypertrophy and pulmonary artery remodeling were attenuated. Then the effects of salidroside or AICAR on hypoxia-induced excess cellular proliferation and apoptosis resistance of pulmonary arterial smooth muscle cells (PASMCs), which contributed to pulmonary arterial remodeling, were investigated. Our results suggested salidroside, as well as AICAR, reversed hypoxia-induced PASMCs proliferation and apoptosis resistance while AMPK inhibitor Compound C enhanced the effects of hypoxia. To reveal the potential cellular mechanisms, activation of AMPKα1 and expression of the genes related to proliferation and apoptosis were analyzed in PASMCs after salidroside treatment under hypoxia conditions. The results demonstrated salidroside as well as AICAR might inhibit chronic hypoxia-induced PASMCs proliferation via AMPKα1-P53-P27/P21 pathway and reverse apoptosis resistance via AMPKα1-P53-Bax/Bcl-2-caspase 9-caspase 3 pathway.

  1. Tissue-Related Hypoxia Attenuates Proinflammatory Effects of Allogeneic PBMCs on Adipose-Derived Stromal Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Polina I. Bobyleva

    2016-01-01

    Full Text Available Human adipose tissue-stromal derived cells (ASCs are considered a perspective tool for regenerative medicine. Depending on the application mode ASC/allogeneic immune cell interaction can occur in the systemic circulation under plenty high concentrations of O2 and in target tissues at lower O2 levels. Here we examined the effects of allogeneic PHA-stimulated peripheral blood mononuclear cells (PBMCs on ASCs under ambient (20% oxygen and “physiological” hypoxia (5% O2. As revealed with microarray analysis ASCs under 20% O2 were more affected by activated PBMCs, which was manifested in differential expression of more than 300 genes, whereas under 5% O2 only 140 genes were changed. Altered gene pattern was only partly overlapped at different O2 conditions. Under O2 ASCs retained their proliferative and differentiative capacities, mesenchymal phenotype, and intracellular organelle’ state. ASCs were proinflammatory activated on transcription level that was confirmed by their ability to suppress activation and proliferation of mitogen-stimulated PBMCs. ASC/PBMCs interaction resulted in anti-inflammatory shift of paracrine mediators in conditioning medium with significant increase of immunosuppressive LIF level. Our data indicated that under both ambient and tissue-related O2 ASCs possessed immunosuppressive potential and maintained functional activity. Under “physiological” hypoxia ASCs were less susceptible to “priming” by allogeneic mitogen-activated PBMCs.

  2. Upregulated copper transporters in hypoxia-induced pulmonary hypertension.

    Directory of Open Access Journals (Sweden)

    Adriana M Zimnicka

    Full Text Available Pulmonary vascular remodeling and increased arterial wall stiffness are two major causes for the elevated pulmonary vascular resistance and pulmonary arterial pressure in patients and animals with pulmonary hypertension. Cellular copper (Cu plays an important role in angiogenesis and extracellular matrix remodeling; increased Cu in vascular smooth muscle cells has been demonstrated to be associated with atherosclerosis and hypertension in animal experiments. In this study, we show that the Cu-uptake transporter 1, CTR1, and the Cu-efflux pump, ATP7A, were both upregulated in the lung tissues and pulmonary arteries of mice with hypoxia-induced pulmonary hypertension. Hypoxia also significantly increased expression and activity of lysyl oxidase (LOX, a Cu-dependent enzyme that causes crosslinks of collagen and elastin in the extracellular matrix. In vitro experiments show that exposure to hypoxia or treatment with cobalt (CoCl2 also increased protein expression of CTR1, ATP7A, and LOX in pulmonary arterial smooth muscle cells (PASMC. In PASMC exposed to hypoxia or treated with CoCl2, we also confirmed that the Cu transport is increased using 64Cu uptake assays. Furthermore, hypoxia increased both cell migration and proliferation in a Cu-dependent manner. Downregulation of hypoxia-inducible factor 1α (HIF-1α with siRNA significantly attenuated hypoxia-mediated upregulation of CTR1 mRNA. In summary, the data from this study indicate that increased Cu transportation due to upregulated CTR1 and ATP7A in pulmonary arteries and PASMC contributes to the development of hypoxia-induced pulmonary hypertension. The increased Cu uptake and elevated ATP7A also facilitate the increase in LOX activity and thus the increase in crosslink of extracellular matrix, and eventually leading to the increase in pulmonary arterial stiffness.

  3. Lack of bcr and abr promotes hypoxia-induced pulmonary hypertension in mice.

    Directory of Open Access Journals (Sweden)

    Min Yu

    Full Text Available BACKGROUND: Bcr and Abr are GTPase activating proteins that specifically downregulate activity of the small GTPase Rac in restricted cell types in vivo. Rac1 is expressed in smooth muscle cells, a critical cell type involved in the pathogenesis of pulmonary hypertension. The molecular mechanisms that underlie hypoxia-associated pulmonary hypertension are not well-defined. METHODOLOGY/PRINCIPAL FINDINGS: Bcr and abr null mutant mice were compared to wild type controls for the development of pulmonary hypertension after exposure to hypoxia. Also, pulmonary arterial smooth muscle cells from those mice were cultured in hypoxia and examined for proliferation, p38 activation and IL-6 production. Mice lacking Bcr or Abr exposed to hypoxia developed increased right ventricular pressure, hypertrophy and pulmonary vascular remodeling. Perivascular leukocyte infiltration in the lungs was increased, and under hypoxia bcr-/- and abr-/- macrophages generated more reactive oxygen species. Consistent with a contribution of inflammation and oxidative stress in pulmonary hypertension-associated vascular damage, Bcr and Abr-deficient animals showed elevated endothelial leakage after hypoxia exposure. Hypoxia-treated pulmonary arterial smooth muscle cells from Bcr- or Abr-deficient mice also proliferated faster than those of wild type mice. Moreover, activated Rac1, phosphorylated p38 and interleukin 6 were increased in these cells in the absence of Bcr or Abr. Inhibition of Rac1 activation with Z62954982, a novel Rac inhibitor, decreased proliferation, p38 phosphorylation and IL-6 levels in pulmonary arterial smooth muscle cells exposed to hypoxia. CONCLUSIONS: Bcr and Abr play a critical role in down-regulating hypoxia-induced pulmonary hypertension by deactivating Rac1 and, through this, reducing both oxidative stress generated by leukocytes as well as p38 phosphorylation, IL-6 production and proliferation of pulmonary arterial smooth muscle cells.

  4. LEPTIN STIMULATING PROLIFERATION AND DIFFERENTIATION OF HUMAN OSTEOBLAST-LIKE CELL LINE MG63 IN DOSE-DEPENDENT AND TIME-DEPENDENT MANNERS

    Institute of Scientific and Technical Information of China (English)

    PENG Mian; YU Xue-tao; CHEN Shu; CAI Xiao-hua; PENG Yi-chao; PENG Xiao-rong

    2007-01-01

    Objective To investigate the direct effect of leptin on osteoblast-like cell line MG63. Methods Human osteoblast-like cell line MG63 was incubated with leptin of different doses for 24, 48 and 72 h, respectively.The proliferation of MG63 was determined by methylene blue assay. Alpha1 (Ⅰ) collagen gene expression in MG63was determined by real time flourescence quantitive PCR (FQ-PCR), both with 17β-E2 as positive control.Results Leptin accelerated the proliferation and differentiation of MG63 in dose and time-dependent manners,with the best effect at 10-7 mol/L at 72 h. Compared with 17β-E2 , leptin showed a weaker promoting effect at all of the three time point: 24, 48 and 72 h. While the effects of the two hormones have an approaching trend the time prolonged. Conclusion Leptin has the effects of accelerating the proliferation and differentiation of MG63 cells in vitro, which is more enduring and later than that of 17β-E2.

  5. Mild hypoxia affects synaptic connectivity in cultured neuronal networks.

    Science.gov (United States)

    Hofmeijer, Jeannette; Mulder, Alex T B; Farinha, Ana C; van Putten, Michel J A M; le Feber, Joost

    2014-04-01

    Eighty percent of patients with chronic mild cerebral ischemia/hypoxia resulting from chronic heart failure or pulmonary disease have cognitive impairment. Overt structural neuronal damage is lacking and the precise cause of neuronal damage is unclear. As almost half of the cerebral energy consumption is used for synaptic transmission, and synaptic failure is the first abrupt consequence of acute complete anoxia, synaptic dysfunction is a candidate mechanism for the cognitive deterioration in chronic mild ischemia/hypoxia. Because measurement of synaptic functioning in patients is problematic, we use cultured networks of cortical neurons from new born rats, grown over a multi-electrode array, as a model system. These were exposed to partial hypoxia (partial oxygen pressure of 150Torr lowered to 40-50Torr) during 3 (n=14) or 6 (n=8) hours. Synaptic functioning was assessed before, during, and after hypoxia by assessment of spontaneous network activity, functional connectivity, and synaptically driven network responses to electrical stimulation. Action potential heights and shapes and non-synaptic stimulus responses were used as measures of individual neuronal integrity. During hypoxia of 3 and 6h, there was a statistically significant decrease of spontaneous network activity, functional connectivity, and synaptically driven network responses, whereas direct responses and action potentials remained unchanged. These changes were largely reversible. Our results indicate that in cultured neuronal networks, partial hypoxia during 3 or 6h causes isolated disturbances of synaptic connectivity.

  6. The effect of DN (dominant-negative) Ku70 and reoxygenation on hypoxia cell-kill: evidence of hypoxia-induced potentially lethal damage.

    Science.gov (United States)

    Urano, Muneyasu; Li, Gloria C; He, Fuqiu; Minami, Akiko; Burgman, Paul; Ling, C Clifton

    2012-07-01

    To study the effect of DN (dominant-negative) Ku70 and reoxygenation on the hypoxia-induced cell-kill. Cell lines were human colorectal carcinoma HCT8 and HT29 cells and their respective derivatives, v-HCT8 and v-HT29 infected with DNKu70-containing adenovirus. Cells were plated in glass tubes and made hypoxic by flushing N(2) gas containing 0, 0.1 or 0.5% O(2). Cell survival was determined by colony formation assay immediately after 0-96 h hypoxia. To reoxygenate medium were replaced fresh following 48 or 72 h in hypoxia and cells were incubated in aerobic environment for 2-24 h before survival assay. When incubated in hypoxia, cells lost reproductive capability ∼ exponentially as a function of time in hypoxia, and depending on the O(2) concentration. DNKu70 rendered cells more prone to hypoxia-induced cell-kill. Following reoxygenation cell survival increased rapidly but without detectable cell proliferation during first 24 hours. This evinced hypoxia-induced potentially lethal damage (PLD) that was repairable upon reoxygenation. DNKu70 did not significantly inhibit this repair. Hypoxia-induced cell lethality was facilitated by DNKu70, but substantially repaired upon reoxygenation. This may have negative impact on the effect of reoxygenation in cancer therapy.

  7. TCDD Induces the Hypoxia-Inducible Factor (HIF-1α Regulatory Pathway in Human Trophoblastic JAR Cells

    Directory of Open Access Journals (Sweden)

    Tien-Ling Liao

    2014-09-01

    Full Text Available The exposure to dioxin can compromise pregnancy outcomes and increase the risk of preterm births. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD has been demonstrated to induce placental hypoxia at the end of pregnancy in a rat model, and hypoxia has been suggested to be the cause of abnormal trophoblast differentiation and placental insufficiency syndromes. In this study, we demonstrate that the non-hypoxic stimulation of human trophoblastic cells by TCDD strongly increased hypoxia inducible factor-1 alpha (HIF-1α stabilization. TCDD exposure induced the generation of reactive oxygen species (ROS and nitric oxide. TCDD-induced HIF-1α stabilization and Akt phosphorylation was inhibited by pretreatment with wortmannin (a phosphatidylinositol 3-kinase (PI3K inhibitor or N-acetylcysteine (a ROS scavenger. The augmented HIF-1α stabilization by TCDD occurred via the ROS-dependent activation of the PI3K/Akt pathway. Additionally, a significant increase in invasion and metallomatrix protease-9 activity was found in TCDD-treated cells. The gene expression of vascular endothelial growth factor and placental growth factor was induced upon TCDD stimulation, whereas the protein levels of peroxisome proliferator-activated receptor γ (PPARγ, PPARγ coactivator-1α, mitochondrial transcription factor, and uncoupling protein 2 were decreased. Our results indicate that an activated HIF-1α pathway, elicited oxidative stress, and induced metabolic stress contribute to TCDD-induced trophoblastic toxicity. These findings may provide molecular insight into the TCDD-induced impairment of trophoblast function and placental development.

  8. The Mechanism of Adaptation of Breast Cancer Cells to Hypoxia: Role of AMPK/mTOR Signaling Pathway.

    Science.gov (United States)

    Sorokin, D V; Scherbakov, A M; Yakushina, I A; Semina, S E; Gudkova, M V; Krasil'nikov, M A

    2016-02-01

    We studied the mechanisms of adaptation of human breast cancer cells MCF-7 to hypoxia and analyzed the role of AMPK/mTOR signaling pathway in the maintenance of cell proliferation under hypoxic conditions. It was found that long-term culturing (30 days or more) of MCF-7 cells under hypoxic conditions induced their partial adaptation to hypoxia. Cell adaptation to hypoxia was associated with attenuation of hypoxia-dependent AMPK induction with simultaneous constitutive activation of mTOR and Akt. These findings suggest that these proteins can be promising targets for targeted therapy of tumors developing under hypoxic conditions.

  9. Fibrillar beta-amyloid peptide Aβ1–40 activates microglial proliferation via stimulating TNF-α release and H2O2 derived from NADPH oxidase: a cell culture study

    Directory of Open Access Journals (Sweden)

    Sharpe Martyn

    2006-09-01

    Full Text Available Abstract Background Alzheimer's disease is characterized by the accumulation of neuritic plaques, containing activated microglia and β-amyloid peptides (Aβ. Fibrillar Aβ can activate microglia, resulting in production of toxic and inflammatory mediators like hydrogen peroxide, nitric oxide, and cytokines. We have recently found that microglial proliferation is regulated by hydrogen peroxide derived from NADPH oxidase. Thus, in this study, we investigated whether Aβ can stimulate microglial proliferation and cytokine production via activation of NADPH oxidase to produce hydrogen peroxide. Methods Primary mixed glial cultures were prepared from the cerebral cortices of 7-day-old Wistar rats. At confluency, microglial cells were isolated by tapping, replated, and treated either with or without Aβ. Hydrogen peroxide production by cells was measured with Amplex Red and peroxidase. Microglial proliferation was assessed under a microscope 0, 24 and 48 hours after plating. TNF-α and IL-1β levels in the culture medium were assessed by ELISA. Results We found that 1 μM fibrillar (but not soluble Aβ1–40 peptide induced microglial proliferation and caused release of hydrogen peroxide, TNF-α and IL-1β from microglial cells. Proliferation was prevented by the NADPH oxidase inhibitor apocynin (10 μM, by the hydrogen peroxide-degrading enzyme catalase (60 U/ml, and by its mimetics EUK-8 and EUK-134 (20 μM; as well as by an antibody against TNF-α and by a soluble TNF receptor inhibitor. Production of TNF-α and IL-1β, measured after 24 hours of Aβ treatment, was also prevented by apocynin, catalase and EUKs, but the early release (measured after 1 hour of Aβ treatment of TNF-α was insensitive to apocynin or catalase. Conclusion These results indicate that Aβ1–40-induced microglial proliferation is mediated both by microglial release of TNF-α and production of hydrogen peroxide from NADPH oxidase. This suggests that TNF-α and NADPH

  10. Hypoxia and fatty liver.

    Science.gov (United States)

    Suzuki, Tomohiro; Shinjo, Satoko; Arai, Takatomo; Kanai, Mai; Goda, Nobuhito

    2014-11-07

    The liver is a central organ that metabolizes excessive nutrients for storage in the form of glycogen and lipids and supplies energy-producing substrates to the peripheral tissues to maintain their function, even under starved conditions. These processes require a considerable amount of oxygen, which causes a steep oxygen gradient throughout the hepatic lobules. Alcohol consumption and/or excessive food intake can alter the hepatic metabolic balance drastically, which can precipitate fatty liver disease, a major cause of chronic liver diseases worldwide, ranging from simple steatosis, through steatohepatitis and hepatic fibrosis, to liver cirrhosis. Altered hepatic metabolism and tissue remodeling in fatty liver disease further disrupt hepatic oxygen homeostasis, resulting in severe liver hypoxia. As master regulators of adaptive responses to hypoxic stress, hypoxia-inducible factors (HIFs) modulate various cellular and organ functions, including erythropoiesis, angiogenesis, metabolic demand, and cell survival, by activating their target genes during fetal development and also in many disease conditions such as cancer, heart failure, and diabetes. In the past decade, it has become clear that HIFs serve as key factors in the regulation of lipid metabolism and fatty liver formation. This review discusses the molecular mechanisms by which hypoxia and HIFs regulate lipid metabolism in the development and progression of fatty liver disease.

  11. Protective Effect of Peroxisome Proliferator-Activated Receptor α Activation against Cardiac Ischemia-Reperfusion Injury Is Related to Upregulation of Uncoupling Protein-3

    Directory of Open Access Journals (Sweden)

    Jong Wook Song

    2016-01-01

    Full Text Available Activation of peroxisome proliferator-activated receptor α (PPARα confers cardioprotection, while its mechanism remains elusive. We investigated the protective effect of PPARα activation against cardiac ischemia-reperfusion injury in terms of the expression of uncoupling protein (UCP. Myocardial infarct size and UCP expression were measured in rats treated with WY-14643 20 mg/kg, a PPARα ligand, or vehicle. WY-14643 increased UCP3 expression in vivo. Myocardial infarct size was decreased in the WY-14643 group (76 ± 8% versus 42 ± 12%, P<0.05. During reperfusion, the incidence of arrhythmia was higher in the control group compared with the WY-14643 group (9/10 versus 3/10, P<0.05. H9c2 cells were incubated for 24 h with WY-14643 or vehicle. WY-14643 increased UCP3 expression in H9c2 cells. WY-14643 decreased hypoxia-stimulated ROS production. Cells treated with WY-14643 were more resistant to hypoxia-reoxygenation than the untreated cells. Knocking-down UCP3 by siRNA prevented WY-14643 from attenuating the production of ROS. UCP3 siRNA abolished the effect of WY-14643 on cell viability against hypoxia-reoxygenation. In summary, administration of PPARα agonist WY-14643 mitigated the extent of myocardial infarction and incidence of reperfusion-induced arrhythmia. PPARα activation conferred cytoprotective effect against hypoxia-reoxygenation. Associated mechanisms involved increased UCP3 expression and resultant attenuation of ROS production.

  12. Peroxisome proliferator-activated receptor alpha (PPARalpha) potentiates, whereas PPARgamma attenuates, glucose-stimulated insulin secretion in pancreatic beta-cells

    DEFF Research Database (Denmark)

    Ravnskjaer, Kim; Boergesen, Michael; Rubi, Blanca

    2005-01-01

    Fatty acids (FAs) are known to be important regulators of insulin secretion from pancreatic beta-cells. FA-coenzyme A esters have been shown to directly stimulate the secretion process, whereas long-term exposure of beta-cells to FAs compromises glucose-stimulated insulin secretion (GSIS...... receptor alpha (RXRalpha) in INS-1E beta-cells synergistically and in a dose- and ligand-dependent manner increases the expression of known PPARalpha target genes and enhances FA uptake and beta-oxidation. In contrast, ectopic expression of PPARgamma/RXRalpha increases FA uptake and deposition...... proton gradient. Importantly, whereas expression of PPARgamma/RXRalpha attenuates GSIS, the expression of PPARalpha/RXRalpha potentiates GSIS in rat islets and INS-1E cells without affecting the mitochondrial membrane potential. These results show a strong subtype specificity of the two PPAR subtypes...

  13. Hepatitis B Virus X Protein Stimulates Proliferation, Wound Closure and Inhibits Apoptosis of HuH-7 Cells via CDC42

    Science.gov (United States)

    Xu, Yongru; Qi, Yingzi; Luo, Jing; Yang, Jing; Xie, Qi; Deng, Chen; Su, Na; Wei, Wei; Shi, Deshun; Xu, Feng; Li, Xiangping; Xu, Ping

    2017-01-01

    Chronic hepatitis B virus (HBV) infection has been considered as the major cause of hepatocellular carcinoma (HCC). Hepatitis B virus X protein (HBx) has been reported to be oncogenic. The underlying mechanisms of HBV-related HCC are not fully understood, and the role played by the HBx protein in HBV induced carcinogenesis remains controversial. CDC42, a member of the Rho GTPase family, has been reported to be overexpressed in several different cancers, including HBV-related HCC. However, the specific role of CDC42 in HCC development remains unclear. Here, we investigated the cellular mechanisms by which CDC42 was responsible for the higher proliferation of HuH-7 cells mediated by HBx. We found that the expression level of CDC42 and its activity were significantly increased in HuH-7-HBx cells. The deficiency of CDC42 using the CRISPR/Cas9 system and inhibition by specific inhibitor CASIN led to the reduction of HBx-mediated proliferation. Furthermore, we observed that IQ Motif Containing GTPase Activating Protein 1 (IQGAP1), the downstream mediator of the CDC42 pathway, might be involved in the carcinogenesis induced by HBx. Therefore, the HBx/CDC42/IQGAP1 signaling pathway may potentially play an important role in HBx-mediated carcinogenesis. PMID:28282856

  14. Differential effects of culture senescence and mechanical stimulation on the proliferation and leiomyogenic differentiation of MSC from different sources: implications for engineering vascular grafts.

    Science.gov (United States)

    Koobatian, Maxwell T; Liang, Mao-Shih; Swartz, Daniel D; Andreadis, Stelios T

    2015-04-01

    We examined the effects of senescence on the proliferation and leiomyogenic differentiation potential of mesenchymal stem cells (MSCs) isolated from bone marrow (BM-MSCs) or hair follicles (HF-MSCs). To this end, we compared ovine HF-MSCs and BM-MSCs in terms of their proliferation and differentiation potential to the smooth muscle cell lineage. We discovered that HF-MSCs are less susceptible to culture senescence compared with BM-MSCs. We hypothesized that application of mechanical forces may enhance the contractility and mechanical properties of vascular constructs prepared from senescent MSCs. Interestingly, HF-MSCs and BM-MSCs responded differently to changes in the mechanical microenvironment, suggesting that despite phenotypic similarities, MSCs from different anatomic locations may activate different pathways in response to the same microenvironmental factors. In turn, this may also suggest that cell-based tissue regeneration approaches may need to be tailored to the stem cell origin, donor age, and culture time for optimal results.

  15. High-mobility group protein HMGA2-derived fragments stimulate the proliferation of chondrocytes and adipose tissue-derived stem cells.

    Science.gov (United States)

    Richter, A; Lübbing, M; Frank, H G; Nolte, I; Bullerdiek, J C; von Ahsen, I

    2011-04-11

    In previous research, it was shown that recombinant HMGA2 protein enhances the proliferation of porcine chondrocytes grown in vitro, opening up promising applications of this embryonic architectural transcription factor for tissue engineering, such as in cartilage repair. In this paper, we describe the development and analyses of two synthetic fragments comprising the functional AT-hook motifs of the HMGA2 protein, as well as the nuclear transport domain. They can be synthesised up to large scales, while eliminating some of the problems of recombinant protein production, including unwanted modification or contamination by the expression hosts, or of gene therapy approaches such as uncontrolled viral integration and transgene expression even after therapy. Application of one of these peptides onto porcine hyaline cartilage chondrocytes, grown in in vitro monolayer cell culture, showed a growth-promoting effect similar to that of the wild type HMGA2 protein. Furthermore, it also promoted cell growth of adult adipose tissue derived stem cells. Due to its proliferation inducing function and vast availability, this peptide is thus suitable for further application and investigation in various fields such as tissue engineering and stem cell research.

  16. Functioning of the mitochondrial ATP-dependent potassium channel in rats varying in their resistance to hypoxia. Involvement of the channel in the process of animal's adaptation to hypoxia.

    Science.gov (United States)

    Mironova, Galina D; Shigaeva, Maria I; Gritsenko, Elena N; Murzaeva, Svetlana V; Gorbacheva, Olga S; Germanova, Elena L; Lukyanova, Ludmila D

    2010-12-01

    The mechanism of tissue protection from ischemic damage by activation of the mitochondrial ATP-dependent K(+) channel (mitoK(ATP)) remains unexplored. In this work, we have measured, using various approaches, the ATP-dependent mitochondrial K(+) transport in rats that differed in their resistance to hypoxia. The transport was found to be faster in the hypoxia-resistant rats as compared to that in the hypoxia-sensitive animals. Adaptation of animals to the intermittent normobaric hypoxia increased the rate of transport. At the same time, the intramitochondrial concentration of K(+) in the hypoxia-sensitive rats was higher than that in the resistant and adapted animals. This indicates that adaptation to hypoxia stimulates not only the influx of potassium into mitochondria, but also K(+)/H(+) exchange. When mitoK(ATP) was blocked, the rate of the mitochondrial H(2)O(2) production was found to be significantly higher in the hypoxia-resistant rats than that in the hypoxia-sensitive animals. The natural flavonoid-containing adaptogen Extralife, which has an evident antihypoxic effect, increased the rate of the mitochondrial ATP-dependent K(+) transport in vitro and increased the in vivo tolerance of hypoxia-sensitive rats to acute hypoxia 5-fold. The involvement of the mitochondrial K(+) transport in the mechanism of cell adaptation to hypoxia is discussed.

  17. AhR-dependent secretion of PDGF-BB by human classically activated macrophages exposed to DEP extracts stimulates lung fibroblast proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Jaguin, Marie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 Avenue du Pr Léon Bernard, 35043 Rennes Cedex (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 Avenue du Pr Léon Bernard, 35043 Rennes Cedex (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes Cedex (France); Lecureur, Valérie, E-mail: valerie.lecureur@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 Avenue du Pr Léon Bernard, 35043 Rennes Cedex (France)

    2015-06-15

    Lung diseases are aggravated by exposure to diesel exhaust particles (DEPs) found in air pollution. Macrophages are thought to play a crucial role in lung immune response to these pollutants, even if the mechanisms involved remain incompletely characterized. In the present study, we demonstrated that classically and alternative human macrophages (MΦ) exhibited increased secretion of PDGF-B in response to DEP extract (DEPe). This occurred via aryl hydrocarbon receptor (AhR)-activation because DEPe-induced PDGF-B overexpression was abrogated after AhR expression knock-down by RNA interference, in both M1 and M2 polarizing MΦ. In addition, TCDD and benzo(a)pyrene, two potent AhR ligands, also significantly increased mRNA expression of PDGF-B in M1 MΦ, whereas some weak ligands of AhR did not. We next evaluated the impact of conditioned media (CM) from MΦ culture exposed to DEPe or of recombinant PDGF-B onto lung fibroblast proliferation. The tyrosine kinase inhibitor, AG-1295, prevents phosphorylations of PDGF-Rβ, AKT and ERK1/2 and the proliferation of MRC-5 fibroblasts induced by recombinant PDGF-B and by CM from M1 polarizing MΦ, strongly suggesting that the PDGF-BB secreted by DEPe-exposed MΦ is sufficient to activate the PDGF-Rβ pathway of human lung fibroblasts. In conclusion, we demonstrated that human MΦ, whatever their polarization status, secrete PDGF-B in response to DEPe and that PDGF-B is a target gene of AhR. Therefore, induction of PDGF-B by DEP may participate in the deleterious effects towards human health triggered by such environmental urban contaminants. - Highlights: • PDGF-B expression and secretion are increased by DEPe exposure in human M1 and M2 MΦ. • DEPe-induced PDGF-B expression is aryl-hydrocarbon-dependent. • DEPe-exposed M1 MΦ secrete sufficient PDGF-B to increase lung fibroblast proliferation.

  18. The Role of Hypoxia in Orthodontic Tooth Movement

    Directory of Open Access Journals (Sweden)

    A. Niklas

    2013-01-01

    Full Text Available Orthodontic forces are known to have various effects on the alveolar process, such as cell deformation, inflammation, and circulatory disturbances. Each of these conditions affecting cell differentiation, cell repair, and cell migration, is driven by numerous molecular and inflammatory mediators. As a result, bone remodeling is induced, facilitating orthodontic tooth movement. However, orthodontic forces not only have cellular effects but also induce vascular changes. Orthodontic forces are known to occlude periodontal ligament vessels on the pressure side of the dental root, decreasing the blood perfusion of the tissue. This condition is accompanied by hypoxia, which is known to either affect cell proliferation or induce apoptosis, depending on the oxygen gradient. Because upregulated tissue proliferation rates are often accompanied by angiogenesis, hypoxia may be assumed to fundamentally contribute to bone remodeling processes during orthodontic treatment.

  19. Hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers.

    Science.gov (United States)

    Kohnoh, Takashi; Hashimoto, Naozumi; Ando, Akira; Sakamoto, Koji; Miyazaki, Shinichi; Aoyama, Daisuke; Kusunose, Masaaki; Kimura, Motohiro; Omote, Norihito; Imaizumi, Kazuyoshi; Kawabe, Tsutomu; Hasegawa, Yoshinori

    2016-01-01

    Persistent hypoxia stimulation, one of the most critical microenvironmental factors, accelerates the acquisition of epithelial-mesenchymal transition (EMT) phenotypes in lung cancer cells. Loss of phosphatase and tensin homologue deleted from chromosome 10 (PTEN) expression might accelerate the development of lung cancer in vivo. Recent studies suggest that tumor microenvironmental factors might modulate the PTEN activity though a decrease in total PTEN expression and an increase in phosphorylation of the PTEN C-terminus (p-PTEN), resulting in the acquisition of the EMT phenotypes. Nevertheless, it is not known whether persistent hypoxia can modulate PTEN phosphatase activity or whether hypoxia-induced EMT phenotypes are negatively regulated by the PTEN phosphatase activity. We aimed to investigate hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers. Western blotting was performed in five lung cancer cell lines to evaluate total PTEN expression levels and the PTEN activation. In a xenograft model of lung cancer cells with endogenous PTEN expression, the PTEN expression was evaluated by immunohistochemistry. To examine the effect of hypoxia on phenotypic alterations in lung cancer cells in vitro, the cells were cultured under hypoxia. The effect of unphosphorylated PTEN (PTEN4A) induction on hypoxia-induced EMT phenotypes was evaluated, by using a Dox-dependent gene expression system. Lung cancer cells involving the EMT phenotypes showed a decrease in total PTEN expression and an increase in p-PTEN. In a xenograft model, loss of PTEN expression was observed in the tumor lesions showing tissue hypoxia. Persistent hypoxia yielded an approximately eight-fold increase in the p-PTEN/PTEN ratio in vitro. PTEN4A did not affect stabilization of hypoxia-inducible factor 1α. PTEN4A blunted hypoxia-induced EMT via inhibition of β-catenin translocation into the cytoplasm and nucleus. Our study strengthens the therapeutic possibility that

  20. The effects and mechanisms of cytoplasmic Macrophage colony-stimulating factor (M-CSF) on the proliferation, migration and invasion of HeLa cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG Meng-xia; WU Hai-yan; TU Jian; ZHANG Xiao-hong; LE Xiao-yong; TANG Sheng-song

    2008-01-01

    Objective To explore the effects and mechanisms of cytoplasmic M-CSF on the proliferation, migration and invasion of HeLa cells. Methods Both pCMV/cyto/myc vector and pCMV/cyto/myc-M-CSF vector was transfected into HeLa-cell by transfectaimine. After screening by G418, the positive clones were amplified and confirmed by RT-PCR, Western blot and immunocytochemistry. The effect of cytoplasmic MCSF on the proliferation of HeLa cells were analyzed by cell conuting and antisense oligonucleotides. The migration and invasion of cell was measured by in vitro Transwell assay and Matrigel-coated polycarbonate filters. The expression of cyclinE, cyclinD1/2/3, CDK2/4/6, Rac1, and matrix metalloproteinase 2 and 9 (MMP2/9) were assayed by semiquantitative RT-PCR. And expression of both α-tubulin and cdc42 were displayed by immunofluorescence. The activity of MMP2 was detected by gelatin zymography. Results Results A cell line (referred as to HeLa-M cell) that highly expresses cytoplasmic M-CSF was successfully established in the test. Our result indicated that HeLa-M cell had a larger volume, faster growth rate and shorter doubling time than either pCMV/cyto/myc transfected HeLa cells (referred as to HeLa-C cell) or untransfected HeLa cells (referred as to HeLa cell). M-CSF-specific antisense oligonucleoside significantly inhibited HeLa-M cell proliferation and had little effect on either HeLa-C cell or HeLa-C cell growth. Cytoplasmic M-CSF up-regulated both the expression of cyclinE, cyclinD1 and cyclinD3, CDK2, CDK 4 and CDK6,a Rho GTPase ralative protein (Rac1), cdc42 and MMP2, but had little effect on expression of MMP9 and cyclin D2. Furthermore, cytoplasmic M-CSF induced the rearrangement of the α-tubulin in HeLa cells and significantly promoted the migration and invasion of HeLa cells in vitro. Conclusions Cytoplasmic M-CSFs up-regulate the expression of cyclinE, cyclinD1 and cyclinD3, CDK2, CDK 4 and CDK6 and induces the proliferation of HeLa cells. Cytoplasmic M

  1. Insect peptide CopA3-induced protein degradation of p27Kip1 stimulates proliferation and protects neuronal cells from apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Taek; Kim, Dae Hong; Lee, Min Bum; Nam, Hyo Jung; Kang, Jin Ku; Park, Mi Jung; Lee, Ik Hwan [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of); Seok, Heon [Department of Biomedical Science, Jungwon University, Goesan, Chungcheongbukdo 367-700 (Korea, Republic of); Lee, Dong Gun [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hwang, Jae Sam [Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon 441-707 (Korea, Republic of); Kim, Ho, E-mail: hokim@daejin.ac.kr [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of)

    2013-07-19

    Highlights: •CopA3 peptide isolated from the Korean dung beetle has antimicrobial activity. •Our study reported that CopA3 has anticancer and immunosuppressive effects. •We here demonstrated that CopA3 has neurotropic and neuroprotective effects. •CopA3 degrades p27Kip1 protein and this mediates effects of CopA3 on neuronal cells. -- Abstract: We recently demonstrated that the antibacterial peptide, CopA3 (a D-type disulfide dimer peptide, LLCIALRKK), inhibits LPS-induced macrophage activation and also has anticancer activity in leukemia cells. Here, we examined whether CopA3 could affect neuronal cell proliferation. We found that CopA3 time-dependently increased cell proliferation by up to 31 ± 2% in human neuroblastoma SH-SY5Y cells, and up to 29 ± 2% in neural stem cells isolated from neonatal mouse brains. In both cell types, CopA3 also significantly inhibited the apoptosis and viability losses caused by 6-hydroxy dopamine (a Parkinson disease-mimicking agent) and okadaic acid (an Alzheimer’s disease-mimicking agent). Immunoblotting revealed that the p27Kip1 protein (a negative regulator of cell cycle progression) was markedly degraded in CopA3-treated SH-SY5Y cells. Conversely, an adenovirus expressing p27Kip1 significantly inhibited the antiapoptotic effects of CopA3 against 6-hydroxy dopamine- and okadaic acid-induced apoptosis, and decreased the neurotropic effects of CopA3. These results collectively suggest that CopA3-mediated protein degradation of p27Kip1 may be the main mechanism through which CopA3 exerts neuroprotective and neurotropic effects.

  2. No amplifications of hypoxia-inducible factor-1α gene in invasive breast cancer: A tissue microarray study

    NARCIS (Netherlands)

    Vleugel, M.M.; Bos, R.; Buerger, Horst; Groep, P. van der; Saramäki, O.R.; Visakorpi, T.; Wall, E. van der; Diest, P.J. van

    2004-01-01

    OBJECTIVE: Hypoxia Inducible Factor-1 (HIF-1) is an important transcription factor that stimulates tumour growth and metastases via several pathways, including angiogenesis and altered metabolism. Activation of HIF-1 depends on the levels of its α-subunit, which increase during hypoxia. Recent

  3. Hyperoside Downregulates the Receptor for Advanced Glycation End Products (RAGE and Promotes Proliferation in ECV304 Cells via the c-Jun N-Terminal Kinases (JNK Pathway Following Stimulation by Advanced Glycation End-Products In Vitro

    Directory of Open Access Journals (Sweden)

    Zhengyu Zhang

    2013-11-01

    Full Text Available Hyperoside is a major active constituent in many medicinal plants which are traditionally used in Chinese medicines for their neuroprotective, anti-inflammatory and antioxidative effects. The molecular mechanisms underlying these effects are unknown. In this study, quiescent ECV304 cells were treated in vitro with advanced glycation end products (AGEs in the presence or absence of hyperoside. The results demonstrated that AGEs induced c-Jun N-terminal kinases (JNK activation and apoptosis in ECV304 cells. Hyperoside inhibited these effects and promoted ECV304 cell proliferation. Furthermore, hyperoside significantly inhibited RAGE expression in AGE-stimulated ECV304 cells, whereas knockdown of RAGE inhibited AGE-induced JNK activation. These results suggested that AGEs may promote JNK activation, leading to viability inhibition of ECV304 cells via the RAGE signaling pathway. These effects could be inhibited by hyperoside. Our findings suggest a novel role for hyperoside in the treatment and prevention of diabetes.

  4. LPCES对慢性低压缺氧兔颏舌肌肌球蛋白重链和SR Ca2+摄取-释放动力学的影响%Electrical stimulation at lower physiological frequency induces myosin heavy chain isoform transformation and improves sarcoplasmic reticulum Ca2+ uptake/release in genioglossus of rabbits exposed to chronic hypoxia

    Institute of Scientific and Technical Information of China (English)

    刘熙; 刘刚; 张妮; 欧娜; 张鹏

    2011-01-01

    Objective To identify the effect of chronic electrical stimulation at a lower physiological frequency on the expressions of myosin heavy chain (MHC) isoforms and kinetics of sarcoplasmic reticulum (SR) Ca2 + uptake/release in the genioglossus of rabbits exposed to chronic hypoxia. Methods Twenty-four adult rabbits were randomized into control group ( A), chronic hypoxia group ( B ), 2.5 Hz electrical stimulation group (C) and (2.5 + 40) Hz electrical stimulation group (low frequency plus physical frequency, D).After the rabbits from group B, C and D had been fed with free access to food and water in a hypoxia cabin ( simulating 5 000 m altitude) in 10 h a day for 4 weeks, the rabbits in group C and D received electrical stimulation in their genioglossus at a frequency of 2.5 Hz and (2.5 +40) Hz respectively in 10 h per day for 14 d,while those in group B received no electrical stimulation. Expressions of MHC isoforms in the genioglossus of rabbits in 4 groups were detected by Western blotting, and Fura-2 fluorophotometry was used to assay the kinetics changes of SR Ca2 + uptake-release. Restlts The expression level of MHC l a was significantly higher while that of MHC I was significantly lower in group B than that in group A (P < 0.05 ). Meanwhile,the genioglossus SR Ca2+ uptake/release velocity in group B was significantly decreased compared with that in group A ( P < 0. 05 ). The expression levels of MHC Ⅱ a and MHC I in group C and D after electrical stimulation were significantly higher, while those of MHC Ⅱ b, especially in group D, were significantly lower than those in group B (P < 0.05 ). The genioglossus SR Ca2+ uptake/release velocity in group C and D, especially in group D, was significantly increased compared with that in group B ( P < 0.05 ). No significant difference was found in expression levels of MHC Ⅱ a and MHC I between group C and D after electrical stimulation ( P > 0.05). Conclusion MHC Ⅱb in the genioglossus of rabbits with

  5. Hypoxia. Cross talk between oxygen sensing and the cell cycle machinery.

    Science.gov (United States)

    Semenza, Gregg L

    2011-09-01

    A fundamental physiological property of mammalian cells is the regulation of proliferation according to O(2) availability. Progression through the cell cycle is inhibited under hypoxic conditions in many, but not all, cell types, and this G1 arrest is dependent on hypoxia-inducible factor (HIF) 1α. Components of the hexameric MCM helicase, which binds to replication origins before the onset of DNA synthesis, are present in large excess in mammalian cells relative to origins, suggesting that they may have additional functions. Screens for HIF-1α interacting proteins revealed that MCM7 binds to the amino-terminal PER-SIM-ARNT (PAS) domain of HIF-1α and stimulates prolyl hydroxylation-dependent ubiquitination and degradation of HIF-1α, whereas MCM3 binds to the carboxyl terminus of HIF-1α and enhances asparaginyl hydroxylation-dependent inhibition of HIF-1α transactivation domain function. Thus MCM proteins inhibit HIF activity via two distinct O(2)-dependent mechanisms. Under prolonged hypoxic conditions, MCM mRNA expression is inhibited in a HIF-1α-dependent manner. Thus HIF and MCM proteins act in a mutually antagonistic manner, providing a novel molecular mechanism for homeostatic regulation of cell proliferation based on the relative levels of these proteins.

  6. Efficient proliferation and maturation of fetal liver cells in three-dimensional culture by stimulation of oncostatin M, epidermal growth factor, and dimethyl sulfoxide.

    Science.gov (United States)

    Koyama, Toshie; Ehashi, Tomo; Ohshima, Norio; Miyoshi, Hirotoshi

    2009-05-01

    For the purpose of applying fetal liver cells (FLCs) as a cell source to tissue-engineered bioartificial livers, three-dimensional (3-D) cultures of FLCs using a porous polymer scaffold, as well as monolayer cultures as a control, were simultaneously performed. To achieve efficient growth and differentiation, the FLCs were cultured in the growth medium for the first 3 weeks and then cultured in the differentiation medium for 3 more weeks. In these cultures, stimulating factors (oncostatin M (OSM), epidermal growth factor (EGF), hepatocyte growth factor (HGF), or dimethyl sulfoxide (DMSO)) were added to the media, and their effects were examined. When the growth medium containing OSM and EGF was used, EGF stimulated the growth of FLCs synergistically with OSM. For the differentiation of FLCs into mature hepatocytes, DMSO added to the differentiation medium remarkably enhanced albumin secretion in the 3-D and monolayer cultures, although HGF was effective only in the monolayer culture. Microscopic observation proved that FLCs exhibited hepatocyte-like morphology only in the media containing DMSO. In conclusion, successive supply of the growth medium containing EGF and OSM and the differentiation medium containing DMSO efficiently induced the growth of the 3-D cultured FLCs and their differentiation into mature hepatocytes.

  7. Hypoxia promotes Rab5 activation, leading to tumor cell migration, invasion and metastasis.

    Science.gov (United States)

    Silva, Patricio; Mendoza, Pablo; Rivas, Solange; Díaz, Jorge; Moraga, Carolina; Quest, Andrew F G; Torres, Vicente A

    2016-05-17

    Hypoxia, a common condition of the tumor microenvironment, is associated with poor patient prognosis, tumor cell migration, invasion and metastasis. Recent evidence suggests that hypoxia alters endosome dynamics in tumor cells, leading to augmented cell proliferation and migration and this is particularly relevant, because endosomal components have been shown to be deregulated in cancer. The early endosome protein Rab5 is a small GTPase that promotes integrin trafficking, focal adhesion turnover, Rac1 activation, tumor cell migration and invasion. However, the role of Rab5 and downstream events in hypoxia remain unknown. Here, we identify Rab5 as a critical player in hypoxia-driven tumor cell migration, invasion and metastasis. Exposure of A549 human lung carcinoma, ZR-75, MDA-MB-231 and MCF-7 human breast cancer and B16-F10 mouse melanoma cells to hypoxia increased Rab5 activation, followed by its re-localization to the leading edge and association with focal adhesions. Importantly, Rab5 was required for hypoxia-driven cell migration, FAK phosphorylation and Rac1 activation, as shown by shRNA-targeting and transfection assays with Rab5 mutants. Intriguingly, the effect of hypoxia on both Rab5 activity and migration was substantially higher in metastatic B16-F10 cells than in poorly invasive B16-F0 cells. Furthermore, exogenous expression of Rab5 in B16-F0 cells predisposed to hypoxia-induced migration, whereas expression of the inactive mutant Rab5/S34N prevented the migration of B16-F10 cells induced by hypoxia. Finally, using an in vivo syngenic C57BL/6 mouse model, Rab5 expression was shown to be required for hypoxia-induced metastasis. In summary, these findings identify Rab5 as a key mediator of hypoxia-induced tumor cell migration, invasion and metastasis.

  8. Trichostatin A enhances estrogen receptor-alpha repression in MCF-7 breast cancer cells under hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Hyunggyun; Park, Joonwoo; Shim, Myeongguk; Lee, YoungJoo, E-mail: yjlee@sejong.ac.kr

    2016-02-12

    Estrogen receptor (ER) is a crucial determinant of resistance to endocrine therapy, which may change during the progression of breast cancer. We previously showed that hypoxia induces ESR1 gene repression and ERα protein degradation via proteasome-mediated pathway in breast cancer cells. HDAC plays important roles in the regulation of histone and non-histone protein post-translational modification. HDAC inhibitors can induce epigenetic changes and have therapeutic potential for targeting various cancers. Trichostatin A exerts potent antitumor activities against breast cancer cells in vitro and in vivo. In this report, we show that TSA augments ESR1 gene repression at the transcriptional level and downregulates ERα protein expression under hypoxic conditions through a proteasome-mediated pathway. TSA-induced estrogen response element-driven reporter activity in the absence of estrogen was synergistically enhanced under hypoxia; however, TSA inhibited cell proliferation under both normoxia and hypoxia. Our data show that the hypoxia-induced repression of ESR1 and degradation of ERα are enhanced by concomitant treatment with TSA. These findings expand our understanding of hormone responsiveness in the tumor microenvironment; however, additional in-depth studies are required to elucidate the detailed mechanisms of TSA-induced ERα regulation under hypoxia. - Highlights: • TSA augments ESR1 gene repression at the transcriptional level under hypoxia. • TSA downregulates ERα protein expression under hypoxia. • TSA-induced ERα regulation under hypoxia is essential for understanding the behavior and progression of breast cancer.

  9. Hypoxia: A Master Regulator of MicroRNA Biogenesis and Activity

    Science.gov (United States)

    Nallamshetty, Shriram; Chan, Stephen Y.; Loscalzo, Joseph

    2013-01-01

    Hypoxia, or low oxygen tension, is a unique environmental stress that induces global changes in a complex regulatory network of transcription factors and signaling proteins in order to coordinate cellular adaptations in metabolism, proliferation, DNA repair, and apoptosis. Several lines of evidence now establish microRNAs (miRNAs), which are short non-coding RNAs that regulate gene expression through post-transcriptional mechanisms, as key elements in this response to hypoxia. Oxygen deprivation induces a distinct shift in a specific group of miRNAs, termed hypoxamirs, and emerging evidence indicates that hypoxia regulates several facets of hypoxamir transcription, maturation, and function. Transcription factors such as hypoxia-inducible factor (HIF) are upregulated under conditions of low oxygen availability and directly activate the transcription of a subset of hypoxamirs. Conversely, hypoxia selectively represses other hypoxamirs through less well characterized mechanisms. In addition, oxygen deprivation has been directly implicated in epigenetic modifications such as DNA demethylation that control specific miRNA transcription. Finally, hypoxia also modulates the activity of key proteins that control posttranscriptional events in the maturation and activity of miRNAs. Collectively, these findings establish hypoxia as an important proximal regulator of miRNA biogenesis and function. It will be important for future studies to address the relative contributions of transcriptional and posttranscriptional events in the regulation of specific hypoxamirs and how such miRNAs are coordinated order to integrate into the complex hierarchical regulatory network induced by hypoxia. PMID:23712003

  10. Proinflammatory signal suppresses proliferation and shifts macrophage metabolism from Myc-dependent to HIF1α-dependent.

    Science.gov (United States)

    Liu, Lingling; Lu, Yun; Martinez, Jennifer; Bi, Yujing; Lian, Gaojian; Wang, Tingting; Milasta, Sandra; Wang, Jian; Yang, Mao; Liu, Guangwei; Green, Douglas R; Wang, Ruoning

    2016-02-01

    As a phenotypically plastic cellular population, macrophages change their physiology in response to environmental signals. Emerging evidence suggests that macrophages are capable of tightly coordinating their metabolic programs to adjust their immunological and bioenergetic functional properties, as needed. Upon mitogenic stimulation, quiescent macrophages enter the cell cycle, increasing their bioenergetic and biosynthetic activity to meet the demands of cell growth. Proinflammatory stimulation, however, suppresses cell proliferation, while maintaining a heightened metabolic activity imposed by the production of bactericidal factors. Here, we report that the mitogenic stimulus, colony-stimulating factor 1 (CSF-1), engages a myelocytomatosis viral oncogen (Myc)-dependent transcriptional program that is responsible for cell cycle entry and the up-regulation of glucose and glutamine catabolism in bone marrow-derived macrophages (BMDMs). However, the proinflammatory stimulus, lipopolysaccharide (LPS), suppresses Myc expression and cell proliferation and engages a hypoxia-inducible factor alpha (HIF1α)-dependent transcriptional program that is responsible for heightened glycolysis. The acute deletion of Myc or HIF1α selectively impaired the CSF-1- or LPS-driven metabolic activities in BMDM, respectively. Finally, inhibition of glycolysis by 2-deoxyglucose (2-DG) or genetic deletion of HIF1α suppressed LPS-induced inflammation in vivo. Our studies indicate that a switch from a Myc-dependent to a HIF1α-dependent transcriptional program may regulate the robust bioenergetic support for an inflammatory response, while sparing Myc-dependent proliferation.

  11. Hypoxia inhibits hypertrophic differentiation and endochondral ossification in explanted tibiae.

    Directory of Open Access Journals (Sweden)

    Jeroen C H Leijten

    Full Text Available PURPOSE: Hypertrophic differentiation of growth plate chondrocytes induces angiogenesis which alleviates hypoxia normally present in cartilage. In the current study, we aim to determine whether alleviation of hypoxia is merely a downstream effect of hypertrophic differentiation as previously described or whether alleviation of hypoxia and consequent changes in oxygen tension mediated signaling events also plays an active role in regulating the hypertrophic differentiation process itself. MATERIALS AND METHODS: Fetal mouse tibiae (E17.5 explants were cultured up to 21 days under normoxic or hypoxic conditions (21% and 2.5% oxygen respectively. Tibiae were analyzed on growth kinetics, histology, gene expression and protein secretion. RESULTS: The oxygen level had a strong influence on the development of explanted fetal tibiae. Compared to hypoxia, normoxia increased the length of the tibiae, length of the hypertrophic zone, calcification of the cartilage and mRNA levels of hypertrophic differentiation-related genes e.g. MMP9, MMP13, RUNX2, COL10A1 and ALPL. Compared to normoxia, hypoxia increased the size of the cartilaginous epiphysis, length of the resting zone, calcification of the bone and mRNA levels of hyaline cartilage-related genes e.g. ACAN, COL2A1 and SOX9. Additionally, hypoxia enhanced the mRNA and protein expression of the secreted articular cartilage markers GREM1, FRZB and DKK1, which are able to inhibit hypertrophic differentiation. CONCLUSIONS: Collectively our data suggests that oxygen levels play an active role in the regulation of hypertrophic differentiation of hyaline chondrocytes. Normoxia stimulates hypertrophic differentiation evidenced by the expression of hypertrophic differentiation related genes. In contrast, hypoxia suppresses hypertrophic differentiation of chondrocytes, which might be at least partially explained by the induction of GREM1, FRZB and DKK1 expression.

  12. Rapamycin Inhibits Proliferation of Hemangioma Endothelial Cells by Reducing HIF-1-Dependent Expression of VEGF

    Science.gov (United States)

    Medici, Damian; Olsen, Bjorn R.

    2012-01-01

    Hemangiomas are tumors formed by hyper-proliferation of vascular endothelial cells. This is caused by elevated vascular endothelial growth factor (VEGF) signaling through VEGF receptor 2 (VEGFR2). Here we show that elevated VEGF levels produced by hemangioma endothelial cells are reduced by the mTOR inhibitor rapamycin. mTOR activates p70S6K, which controls translation of mRNA to generate proteins such as hypoxia inducible factor-1 (HIF-1). VEGF is a known HIF-1 target gene, and our data show that VEGF levels in hemangioma endothelial cells are reduced by HIF-1α siRNA. Over-expression of HIF-1α increases VEGF levels and endothelial cell proliferation. Furthermore, both rapamycin and HIF-1α siRNA reduce proliferation of hemangioma endothelial cells. These data suggest that mTOR and HIF-1 contribute to hemangioma endothelial cell proliferation by stimulating an autocrine loop of VEGF signaling. Furthermore, mTOR and HIF-1 may be therapeutic targets for the treatment of hemangiomas. PMID:22900063

  13. Enhancement of osteogenic differentiation and proliferation in human mesenchymal stem cells by a modified low intensity ultrasound stimulation under simulated microgravity.

    Directory of Open Access Journals (Sweden)

    Sardar M Z Uddin

    Full Text Available Adult stem cells can differentiate into multiple lineages depending on their exposure to differing biochemical and biomechanical inductive factors. Lack of mechanical signals due to disuse can inhibit osteogenesis and induce adipogenesis of mesenchymal stem cells (MSCs. Long-term bed rest due to both brain/spinal cord injury and space travel can lead to disuse osteoporosis that is in part caused by a reduced number of osteoblasts. Thus, it is essential to provide proper mechanical stimulation for cellular viability and osteogenesis, particularly under disuse conditions. The objective of this study was to examine the effects of low intensity pulsed ultrasound (LIPUS on the osteogenic differentiation of adipose-derived human stem cells (Ad-hMSC in simulated microgravity conditions. Cells were cultured in a 1D clinostat to simulate microgravity (SMG and treated with LIPUS at 30mW/cm(2 for 20 min/day. It was hypothesized that the application of LIPUS to SMG cultures would restore osteogenesis in Ad-hMSCs. The results showed significant increases in ALP, OSX, RANKL, RUNX2, and decreases in OPG in LIPUS treated SMG cultures of Ad-MSC compared to non-treated cultures. LIPUS also restored OSX, RUNX2 and RANKL expression in osteoblast cells. SMG significantly reduced ALP positive cells by 70% (p<0.01 and ALP activity by 22% (p<0.01, while LIPUS treatment restored ALP positive cell number and activity to equivalence with normal gravity controls. Extracellular matrix collagen and mineralization was assessed by Sirius red and Alizarin red staining, respectively. SMG cultures showed little or no collagen or mineralization, but LIPUS treatment restored collagen content to 50% (p<0.001 and mineralization by 45% (p<0.001 in LIPUS treated-SMG cultures relative to SMG-only cultures. The data suggest that LIPUS treatment can restore normal osteogenic differentiation of MSCs from disuse by daily short duration stimulation.

  14. A Chinese Herbal Decoction, Danggui Buxue Tang, Stimulates Proliferation, Differentiation and Gene Expression of Cultured Osteosarcoma Cells: Genomic Approach to Reveal Specific Gene Activation

    Directory of Open Access Journals (Sweden)

    Roy C. Y. Choi

    2011-01-01

    Full Text Available Danggui Buxue Tang (DBT, a Chinese herbal decoction used to treat ailments in women, contains Radix Astragali (Huangqi; RA and Radix Angelicae Sinensis (Danggui; RAS. When DBT was applied onto cultured MG-63 cells, an increase of cell proliferation and differentiation of MG-63 cell were revealed: both of these effects were significantly higher in DBT than RA or RAS extract. To search for the biological markers that are specifically regulated by DBT, DNA microarray was used to reveal the gene expression profiling of DBT in MG-63 cells as compared to that of RA- or RAS-treated cells. Amongst 883 DBT-regulated genes, 403 of them are specifically regulated by DBT treatment, including CCL-2, CCL-7, CCL-8, and galectin-9. The signaling cascade of this DBT-regulated gene expression was also elucidated in cultured MG-63 cells. The current results reveal the potential usage of this herbal decoction in treating osteoporosis and suggest the uniqueness of Chinese herbal decoction that requires a well-defined formulation. The DBT-regulated genes in the culture could serve as biological responsive markers for quality assurance of the herbal preparation.

  15. Stimulation of fibroblast proliferation by neokyotorphin requires Ca influx and activation of PKA, CaMK II and MAPK/ERK.

    Science.gov (United States)

    Sazonova, Olga V; Blishchenko, Elena Yu; Tolmazova, Anna G; Khachin, Dmitry P; Leontiev, Konstantin V; Karelin, Andrey A; Ivanov, Vadim T

    2007-01-01

    Neokyotorphin [TSKYR, hemoglobin alpha-chain fragment (137-141)] has previously been shown to enhance fibroblast proliferation, its effect depending on cell density and serum level. Here we show the dependence of the effect of neokyotorphin on cell type and its correlation with the effect of protein kinase A (PKA) activator 8-Br-cAMP, but not the PKC activator 4beta-phorbol 12-myristate, 13-acetate (PMA). In L929 fibroblasts, the proliferative effect of neokyotorphin was suppressed by the Ca2+ L-type channel inhibitors verapamil or nifedipine, the intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester, kinase inhibitors H-89 (PKA), KN-62 (Ca2+/calmodulin-dependent kinase II) and PD98059 (mitogen-activated protein kinase). The proliferative effect of 8-Br-cAMP was also suppressed by KN-62 and PD98059. PKC suppression (downregulation with PMA or inhibition with bisindolylmaleimide XI) did not affect neokyotorphin action. The results obtained point to a cAMP-like action for neokyotorphin.

  16. Kidney EPO expression during chronic hypoxia in aged mice.

    Science.gov (United States)

    Benderro, Girriso F; LaManna, Joseph C

    2013-01-01

    In order to maintain normal cellular function, mammalian tissue oxygen concentrations must be tightly regulated within a narrow physiological range. The hormone erythropoietin (EPO) is essential for maintenance of tissue oxygen supply by stimulating red blood cell production and promoting their survival. In this study we compared the effects of 290 Torr atmospheric pressure on the kidney EPO protein levels in young (4-month-old) and aged (24-month-old) C57BL/6 mice. The mice were sacrificed after being anesthetized, and kidney samples were collected and processed by Western blot analysis. Relatively low basal expression of EPO during normoxia in young mice showed significant upregulation in hypoxia and stayed upregulated throughout the hypoxic period (threefold compared to normoxic control), showing a slight decline toward the third week. Whereas, a relatively higher normoxic basal EPO protein level in aged mice did not show significant increase until seventh day of hypoxia, but showed significant upregulation in prolonged hypoxia. Hence, we confirmed that there is a progressively increased accumulation of EPO during chronic hypoxia in young and aged mouse kidney, and the EPO upregulation during hypoxia showed a similarity with the pattern of increase in hematocrit, which we have reported previously.

  17. Effects of Antisense Oligodeoxynucleotide to Follicle-stimulating Hormone Receptor on the Expression of Proliferating Cell Nuclear Antigen and Vascular Endothelial Growth Factor in Primary Culture Cells Derived from Human Ovarian Mucinous Cystadenocarcino

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of antisense oligodeoxynucleotide (antisense ODN) to follicle-stimulating hormone receptor (FSHR) and follicle-stimulating hormone (FSH) on the expression of proliferating cell nuclear antigen (PCNA) and vascular endothelial growth factor (VEGF) were studied in primary culture cells derived from human ovarian mucinous cystadenocarcinoma (OMC). The prlmary OMC cells were cultured with the enzyme digestion method, and the expression of pan Keratin protein and FSHR mRNA was detected for identification of the cells. OMC cells were co-cultured with antisense ODN, nonsense ODN and FSH with different concentrations for 48 h and 72 h. The expression of PCNA and VEGF was detected by using SP immunohistochemistry. Compared with that in the control group, the PCNA and VEGF expression was increased obviously in FSH groups (P<0.05 or P< 0.01), while decreased significantly in antisense ODN groups (P<0. 05 or P<0.01) and unchanged in nonsense ODN groups, respectively. Meanwhile, antisense ODN could antagonize the increased expression of PCNA and VEGF caused by FSH significantly (P<0.01). It was suggested that FSH might promotethe development of OMC to some extent. Antisense ODN could inhibit the proliferative activity of OMC cells and the promoting proliferative activity enhanced by FSH.

  18. JAK2 V617F stimulates proliferation of erythropoietin-dependent erythroid progenitors and delays their differentiation by activating Stat1 and other nonerythroid signaling pathways.

    Science.gov (United States)

    Shi, Jiahai; Yuan, Bingbing; Hu, Wenqian; Lodish, Harvey

    2016-11-01

    JAK2 V617F is a mutant-activated JAK2 kinase found in most polycythemia vera (PV) patients; it skews normal proliferation and differentiation of hematopoietic stem and progenitor cells and simulates aberrant expansion of erythroid progenitors. JAK2 V617F is known to activate some signaling pathways not normally activated in mature erythroblasts, but there has been no systematic study of signal transduction pathways or gene expression in erythroid cells expressing JAK2 V617F undergoing erythropoietin (Epo)-dependent terminal differentiation. Here we report that expression of JAK2 V617F in murine fetal liver Epo-dependent progenitors allows them to divide approximately six rather than the normal approximately four times in the presence of Epo, delaying their exit from the cell cycle. Over time, the number of red cells formed from each Epo-dependent progenitor increases fourfold, and these cells eventually differentiate into normal enucleated reticulocytes. We report that purified fetal liver Epo-dependent progenitors express many cytokine receptors additional to the EpoR. Expression of JAK2 V617F triggers activation of Stat5, the only STAT normally activated by Epo, as well as activation of Stat1 and Stat3. Expression of JAK2 V617F also leads to transient induction of many genes not normally activated in terminally differentiating erythroid cells and that are characteristic of other hematopoietic lineages. Inhibition of Stat1 activation blocks JAK2 V617F hyperproliferation of erythroid progenitors, and we conclude that Stat1-mediated activation of nonerythroid signaling pathways delays terminal erythroid differentiation and permits extended cell divisions.

  19. Antidiabetic effects of chamomile flowers extract in obese mice through transcriptional stimulation of nutrient sensors of the peroxisome proliferator-activated receptor (PPAR family.

    Directory of Open Access Journals (Sweden)

    Christopher Weidner

    Full Text Available Given the significant increases in the incidence of metabolic diseases, efficient strategies for preventing and treating of these common disorders are urgently needed. This includes the development of phytopharmaceutical products or functional foods to prevent or cure metabolic diseases. Plant extracts from edible biomaterial provide a potential resource of structurally diverse molecules that can synergistically interfere with complex disorders. In this study we describe the safe application of ethanolic chamomile (Matricaria recutita flowers extract (CFE for the treatment and prevention of type 2 diabetes and associated disorders. We show in vitro that this extract activates in particular nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ and its isotypes. In a cellular context, in human primary adipocytes CFE administration (300 µg/ml led to specific expression of target genes of PPARγ, whereas in human hepatocytes CFE-induced we detected expression changes of genes that were regulated by PPARα. In vivo treatment of insulin-resistant high-fat diet (HFD-fed C57BL/6 mice with CFE (200 mg/kg/d for 6 weeks considerably reduced insulin resistance, glucose intolerance, plasma triacylglycerol, non-esterified fatty acids (NEFA and LDL/VLDL cholesterol. Co-feeding of lean C57BL/6 mice a HFD with 200 mg/kg/d CFE for 20 weeks showed effective prevention of fatty liver formation and hepatic inflammation, indicating additionally hepatoprotective effects of the extract. Moreover, CFE treatment did not reveal side effects, which have otherwise been associated with strong synthetic PPAR-targeting molecules, such as weight gain, liver disorders, hemodilution or bone cell turnover. Taken together, modulation of PPARs and other factors by chamomile flowers extract has the potential to prevent or treat type 2 diabetes and related disorders.

  20. Antidiabetic effects of chamomile flowers extract in obese mice through transcriptional stimulation of nutrient sensors of the peroxisome proliferator-activated receptor (PPAR) family.

    Science.gov (United States)

    Weidner, Christopher; Wowro, Sylvia J; Rousseau, Morten; Freiwald, Anja; Kodelja, Vitam; Abdel-Aziz, Heba; Kelber, Olaf; Sauer, Sascha

    2013-01-01

    Given the significant increases in the incidence of metabolic diseases, efficient strategies for preventing and treating of these common disorders are urgently needed. This includes the development of phytopharmaceutical products or functional foods to prevent or cure metabolic diseases. Plant extracts from edible biomaterial provide a potential resource of structurally diverse molecules that can synergistically interfere with complex disorders. In this study we describe the safe application of ethanolic chamomile (Matricaria recutita) flowers extract (CFE) for the treatment and prevention of type 2 diabetes and associated disorders. We show in vitro that this extract activates in particular nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) and its isotypes. In a cellular context, in human primary adipocytes CFE administration (300 µg/ml) led to specific expression of target genes of PPARγ, whereas in human hepatocytes CFE-induced we detected expression changes of genes that were regulated by PPARα. In vivo treatment of insulin-resistant high-fat diet (HFD)-fed C57BL/6 mice with CFE (200 mg/kg/d) for 6 weeks considerably reduced insulin resistance, glucose intolerance, plasma triacylglycerol, non-esterified fatty acids (NEFA) and LDL/VLDL cholesterol. Co-feeding of lean C57BL/6 mice a HFD with 200 mg/kg/d CFE for 20 weeks showed effective prevention of fatty liver formation and hepatic inflammation, indicating additionally hepatoprotective effects of the extract. Moreover, CFE treatment did not reveal side effects, which have otherwise been associated with strong synthetic PPAR-targeting molecules, such as weight gain, liver disorders, hemodilution or bone cell turnover. Taken together, modulation of PPARs and other factors by chamomile flowers extract has the potential to prevent or treat type 2 diabetes and related disorders.

  1. Hypoxia in adipose tissue: a basis for the dysregulation of tissue function in obesity?

    Science.gov (United States)

    Trayhurn, Paul; Wang, Bohan; Wood, I Stuart

    2008-08-01

    White adipose tissue is a key endocrine and secretory organ, releasing multiple adipokines, many of which are linked to inflammation and immunity. During the expansion of adipose tissue mass in obesity there is a major inflammatory response in the tissue with increased expression and release of inflammation-related adipokines, including IL-6, leptin, monocyte chemoattractant protein-1 and TNF-alpha, together with decreased adiponectin production. We proposed in 2004 (Trayhurn & Wood, Br J Nutr 92, 347-355) that inflammation in adipose tissue in obesity is a response to hypoxia in enlarged adipocytes distant from the vasculature. Hypoxia has now been directly demonstrated in adipose tissue of several obese mouse models (ob/ob, KKAy, diet-induced) and molecular studies indicate that the level of the hypoxia-inducible transcription factor, hypoxia-inducible factor-1 alpha, is increased, as is expression of the hypoxia-sensitive marker gene, GLUT1. Cell- culture studies on murine and human adipocytes show that hypoxia (induced by low O2 or chemically) leads to stimulation of the expression and secretion of a number of inflammation-related adipokines, including angiopoietin-like protein 4, IL-6, leptin, macrophage migration inhibitory factor and vascular endothelial growth factor. Hypoxia also stimulates the inflammatory response of macrophages and inhibits adipocyte differentiation from preadipocytes. GLUT1 gene expression, protein level and glucose transport by human adipocytes are markedly increased by hypoxia, indicating that low O2 tension stimulates glucose utilisation. It is suggested that hypoxia has a pervasive effect on adipocyte metabolism and on overall adipose tissue function, underpinning the inflammatory response in the tissue in obesity and the subsequent development of obesity-associated diseases, particularly type 2 diabetes and the metabolic syndrome.

  2. Germinal centre hypoxia and regulation of antibody qualities by a hypoxia response system.

    Science.gov (United States)

    Cho, Sung Hoon; Raybuck, Ariel L; Stengel, Kristy; Wei, Mei; Beck, Thomas C; Volanakis, Emmanuel; Thomas, James W; Hiebert, Scott; Haase, Volker H; Boothby, Mark R

    2016-09-08

    Germinal centres (GCs) promote humoral immunity and vaccine efficacy. In GCs, antigen-activated B cells proliferate, express high-affinity antibodies, promote antibody class switching, and yield B cell memory. Whereas the cytokine milieu has long been known to regulate effector functions that include the choice of immunoglobulin class, both cell-autonomous and extrinsic metabolic programming have emerged as modulators of T-cell-mediated immunity. Here we show in mice that GC light zones are hypoxic, and that low oxygen tension () alters B cell physiology and function. In addition to reduced proliferation and increased B cell death, low impairs antibody class switching to the pro-inflammatory IgG2c antibody isotype by limiting the expression of activation-induced cytosine deaminase (AID). Hypoxia induces HIF transcription factors by restricting the activity of prolyl hydroxyl dioxygenase enzymes, which hydroxylate HIF-1α and HIF-2α to destabilize HIF by binding the von Hippel-Landau tumour suppressor protein (pVHL). B-cell-specific depletion of pVHL leads to constitutive HIF stabilization, decreases antigen-specific GC B cells and undermines the generation of high-affinity IgG, switching to IgG2c, early memory B cells, and recall antibody responses. HIF induction can reprogram metabolic and growth factor gene expression. Sustained hypoxia or HIF induction by pVHL deficiency inhibits mTOR complex 1 (mTORC1) activity in B lymphoblasts, and mTORC1-haploinsufficient B cells have reduced clonal expansion, AID expression, and capacities to yield IgG2c and high-affinity antibodies. Thus, the normal physiology of GCs involves regional variegation of hypoxia, and HIF-dependent oxygen sensing regulates vital functions of B cells. We propose that the restriction of oxygen in lymphoid organs, which can be altered in pathophysiological states, modulates humoral immunity.

  3. Chronic hypoxia increases TRPC6 expression and basal intracellular Ca2+ concentration in rat distal pulmonary venous smooth muscle.

    Directory of Open Access Journals (Sweden)

    Lei Xu

    Full Text Available Hypoxia causes remodeling and contractile responses in both pulmonary artery (PA and pulmonary vein (PV. Here we explore the effect of hypoxia on PV and pulmonary venous smooth muscle cells (PVSMCs.Chronic hypoxic pulmonary hypertension (CHPH model was established by exposing rats to 10% O2 for 21 days. Rat distal PVSMCs were isolated and cultured for in vitro experiments. The fura-2 based fluorescence calcium imaging was used to measure the basal intracellular Ca2+ concentration ([Ca2+]i and store-operated Ca2+ entry (SOCE. Quantitative RT-PCR and western blotting were performed to measure the expression of mRNA and levels of canonical transient receptor potential (TRPC protein respectively.Hypoxia increased the basal [Ca2+]i and SOCE in both freshly dissociated and serum cultured distal PVSMCs. Moreover, hypoxia increased TRPC6 expression at mRNA and protein levels in both cultured PVSMCs exposed to prolonged hypoxia (4% O2, 60 h and distal PV isolated from CHPH rats. Hypoxia also enhanced proliferation and migration of rat distal PVSMCs.Hypoxia induces elevation of SOCE in distal PVSMCs, leading to enhancement of basal [Ca2+]i in PVSMCs. This enhancement is potentially correlated with the increased expression of TRPC6. Hypoxia triggered intracellular calcium contributes to promoted proliferation and migration of PVSMCs.

  4. Hypoxia transiently affects skeletal muscle hypertrophy in a functional overload model.

    Science.gov (United States)

    Chaillou, Thomas; Koulmann, Nathalie; Simler, Nadine; Meunier, Adélie; Serrurier, Bernard; Chapot, Rachel; Peinnequin, Andre; Beaudry, Michèle; Bigard, Xavier

    2012-03-01

    Hypoxia induces a loss of skeletal muscle mass, but the signaling pathways and molecular mechanisms involved remain poorly understood. We hypothesized that hypoxia could impair skeletal muscle hypertrophy induced by functional overload (Ov). To test this hypothesis, plantaris muscles were overloaded during 5, 12, and 56 days in female rats exposed to hypobaric hypoxia (5,500 m), and then, we examined the responses of specific signaling pathways involved in protein synthesis (Akt/mTOR) and breakdown (atrogenes). Hypoxia minimized the Ov-induced hypertrophy at days 5 and 12 but did not affect the hypertrophic response measured at day 56. Hypoxia early reduced the phosphorylation levels of mTOR and its downstream targets P70(S6K) and rpS6, but it did not affect the phosphorylation levels of Akt and 4E-BP1, in Ov muscles. The role played by specific inhibitors of mTOR, such as AMPK and hypoxia-induced factors (i.e., REDD1 and BNIP-3) was studied. REDD1 protein levels were reduced by overload and were not affected by hypoxia in Ov muscles, whereas AMPK was not activated by hypoxia. Although hypoxia significantly increased BNIP-3 mRNA levels at day 5, protein levels remained unaffected. The mRNA levels of the two atrogenes MURF1 and MAFbx were early increased by hypoxia in Ov muscles. In conclusion, hypoxia induced a transient alteration of muscle growth in this hypertrophic model, at least partly due to a specific impairment of the mTOR/P70(S6K) pathway, independently of Akt, by an undefined mechanism, and increased transcript levels for MURF1 and MAFbx that could contribute to stimulate the proteasomal proteolysis.

  5. The role of hypoxia and HIF1α in the regulation of STAR-mediated steroidogenesis in granulosa cells.

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    Kowalewski, Mariusz Pawel; Gram, Aykut; Boos, Alois

    2015-02-05

    The adaptive responses to hypoxia are mediated by hypoxia-inducible factor 1 alpha (HIF1α). Its role, however, in regulating steroidogenesis remains poorly understood. We examined the role of hypoxia and HIF1α in regulating steroid acute regulatory protein (STAR) expression and steroidogenesis in immortalized (KK1) mouse granulosa cells under progressively lowering O2 concentrations (20%, 15%, 10%, 5%, 1%). Basal and dbcAMP-stimulated progesterone synthesis was decreased under severe hypoxia (1% and 5% O2). The partial hypoxia revealed opposing effects, with a significant increase in steroidogenic response at 10% O2 in dbcAMP-treated cells: Star-promoter activity, mRNA and protein expression were increased. The hypoxia-stimulated STAR expression was PKA-dependent. Binding of HIF1α to the Star-promoter was potentiated under partial hypoxia. Inhibition of the transcriptional activity or expression of HIF1α suppressed STAR-expression. HIF1α appears to be a positive regulator of basal and stimulated STAR-expression, which under partial hypoxia is capable of increasing the steroidogenic capacity of granulosa cells.

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

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    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.

  7. Hypoxia and adipocyte physiology: implications for adipose tissue dysfunction in obesity.

    Science.gov (United States)

    Trayhurn, Paul

    2014-01-01

    Hypoxia develops in white adipose tissue in obese mice, resulting in changes in adipocyte function that may underpin the dysregulation that leads to obesity-associated disorders. Whether hypoxia occurs in adipose tissue in human obesity is unclear, with recent studies contradicting earlier reports that this was the case. Adipocytes, both murine and human, exhibit extensive functional changes in culture in response to hypoxia, which alters the expression of up to 1,300 genes. These include genes encoding key adipokines such as leptin, interleukin (IL)-6, vascular endothelial growth factor (VEGF), and matrix metalloproteinase-2 (MMP-2), which are upregulated, and adiponectin, which is downregulated. Hypoxia also inhibits the expression of genes linked to oxidative metabolism while stimulating the expression of genes associated with glycolysis. Glucose uptake and lactate release by adipocytes are both stimulated by hypoxia, and insulin sensitivity falls. Preadipocytes and macrophages in adipose tissue also respond to hypoxia. The hypoxia-signaling pathway may provide a new target for the treatment of obesity-associated disorders.

  8. News about VDAC1 in hypoxia

    Directory of Open Access Journals (Sweden)

    Nathalie M. Mazure

    2016-08-01

    Full Text Available The voltage-dependent anion channel (VDAC is the main interface between the cytosol and mitochondria of cells. It plays a crucial role in both mitochondrial metabolism and cell death. The main basic function of this channel is to mediate and gate the flux of small ions, metabolites and ATP. Changes in its structure, and thus conformation, are expected to affect its activity and modulates the ability of cancer cells to expand. In this review, we describe a novel mechanism by which mitochondria of cells in hypoxia, a low level of oxygen, protects from apoptosis. In hypoxia some mitochondria become enlarged due to hyperfusion. These mitochondria possess a truncated form of VDAC1 (VDAC1-ΔC, which is linked to the higher metabolic capacity and the greater resistance to cell death of hypoxic cells. However, not all of the VDAC1 protein is truncated, but the amount of the full-length form is diminished compared to the amount in normoxic cells. First, we describe how such a decrease effects cell proliferation, respiration, glycolysis and other processes. Second we report on a novel mitochondrial-endolysosomal crosstalk that leads to VDAC1 truncation. By pharmacological targeting of VDAC1-ΔC, the production of energy could be turned off and the sensitivity to cell death restored. This could counteract the favorable microenvironment that gives cancer cells a growth advantage and thereby disrupts the balance between life and death, which is controlled by VDAC1.

  9. News about VDAC1 in Hypoxia.

    Science.gov (United States)

    Mazure, N M

    2016-01-01

    The voltage-dependent anion channel (VDAC) is the main interface between the cytosol and mitochondria of cells. It plays a crucial role in both mitochondrial metabolism and cell death. The main basic function of this channel is to mediate and gate the flux of small ions, metabolites, and adenosine triphosphate. Changes in its structure, and thus conformation, are expected to affect its activity and modulate the ability of cancer cells to expand. In this review, we describe a novel mechanism by which mitochondria of cells in hypoxia, a low level of oxygen, protects from apoptosis. In hypoxia, some mitochondria become enlarged due to hyperfusion. These mitochondria possess a truncated form of VDAC1 (VDAC1-ΔC), which is linked to the higher metabolic capacity and the greater resistance to cell death of hypoxic cells. However, not all of the VDAC1 protein is truncated, but the amount of the full-length form is diminished compared to the amount in normoxic cells. First, we describe how such a decrease effects cell proliferation, respiration, glycolysis, and other processes. Second, we report on a novel mitochondrial-endolysosomal crosstalk that leads to VDAC1 truncation. By pharmacological targeting of VDAC1-ΔC, the production of energy could be turned off and the sensitivity to cell death restored. This could counteract the favorable microenvironment that gives cancer cells a growth advantage and thereby disrupts the balance between life and death, which is controlled by VDAC1.

  10. Coastal hypoxia and sediment biogeochemistry

    Directory of Open Access Journals (Sweden)

    J. J. Middelburg

    2009-07-01

    Full Text Available The intensity, duration and frequency of coastal hypoxia (oxygen concentration <63 μM are increasing due to human alteration of coastal ecosystems and changes in oceanographic conditions due to global warming. Here we provide a concise review of the consequences of coastal hypoxia for sediment biogeochemistry. Changes in bottom-water oxygen levels have consequences for early diagenetic pathways (more anaerobic at expense of aerobic pathways, the efficiency of re-oxidation of reduced metabolites and the nature, direction and magnitude of sediment-water exchange fluxes. Hypoxia may also lead to more organic matter accumulation and burial and the organic matter eventually buried is also of higher quality, i.e. less degraded. Bottom-water oxygen levels also affect the organisms involved in organic matter processing with the contribution of metazoans decreasing as oxygen levels drop. Hypoxia has a significant effect on benthic animals with the consequences that ecosystem functions related to macrofauna such as bio-irrigation and bioturbation are significantly affected by hypoxia as well. Since many microbes and microbial-mediated biogeochemical processes depend on animal-induced transport processes (e.g. re-oxidation of particulate reduced sulphur and denitrification, there are indirect hypoxia effects on biogeochemistry via the benthos. Severe long-lasting hypoxia and anoxia may result in the accumulation of reduced compounds in sediments and elimination of macrobenthic communities with the consequences that biogeochemical properties during trajectories of decreasing and increasing oxygen may be different (hysteresis with consequences for coastal ecosystem dynamics.

  11. SAP domain-dependent Mkl1 signaling stimulates proliferation and cell migration by induction of a distinct gene set indicative of poor prognosis in breast cancer patients

    Science.gov (United States)

    2014-01-01

    Background The main cause of death of breast cancer patients is not the primary tumor itself but the metastatic disease. Identifying breast cancer-specific signatures for metastasis and learning more about the nature of the genes involved in the metastatic process would 1) improve our understanding of the mechanisms of cancer progression and 2) reveal new therapeutic targets. Previous studies showed that the transcriptional regulator megakaryoblastic leukemia-1 (Mkl1) induces tenascin-C expression in normal and transformed mammary epithelial cells. Tenascin-C is known to be expressed in metastatic niches, is highly induced in cancer stroma and promotes breast cancer metastasis to the lung. Methods Using HC11 mammary epithelial cells overexpressing different Mkl1 constructs, we devised a subtractive transcript profiling screen to identify the mechanism by which Mkl1 induces a gene set co-regulated with tenascin-C. We performed computational analysis of the Mkl1 target genes and used cell biological experiments to confirm the effect of these gene products on cell behavior. To analyze whether this gene set is prognostic of accelerated cancer progression in human patients, we used the bioinformatics tool GOBO that allowed us to investigate a large breast tumor data set linked to patient data. Results We discovered a breast cancer-specific set of genes including tenascin-C, which is regulated by Mkl1 in a SAP domain-dependent, serum response factor-independent manner and is strongly implicated in cell proliferation, cell motility and cancer. Downregulation of this set of transcripts by overexpression of Mkl1 lacking the SAP domain inhibited cell growth and cell migration. Many of these genes are direct Mkl1 targets since their promoter-reporter constructs were induced by Mkl1 in a SAP domain-dependent manner. Transcripts, most strongly reduced in the absence of the SAP domain were mechanoresponsive. Finally, expression of this gene set is associated with high

  12. Low-methoxyl pectin stimulates small intestinal mucin secretion irrespective of goblet cell proliferation and is characterized by jejunum Muc2 upregulation in rats.

    Science.gov (United States)

    Hino, Shingo; Sonoyama, Kei; Bito, Hiroyuki; Kawagishi, Hirokazu; Aoe, Seiichiro; Morita, Tatsuya

    2013-01-01

    Generally, soluble fibers increase small intestinal mucin secretion by increasing the number of goblet cells in a viscosity-dependent manner. The present study aimed to examine the mechanism by which low-methoxyl pectin (LPC) affects mucin secretion in the small intestine. First, diets containing 50 g/kg of low-viscosity fiber (LPC, gum arabic, guar gum, low-molecular konjac mannan, arabinogalactan, sodium alginate) or high-molecular konjac mannan (KMH) were fed to Wistar rats for 10 d. Luminal mucin was greater in the LPC and KMH groups than in the fiber-free control group, but only the KMH group had more goblet cells in the ileum compared with the other groups. Next, Sprague-Dawley rats were fed LPC, KMH, or high-methoxyl pectin (HPC) diets (50 g/kg) for 10 d. The KMH and LPC groups, but not the HPC group, had greater luminal mucin than the control group, whereas jejunum Muc2 expression was higher only in the LPC group. Sprague-Dawley rats fed the LPC diet for 1 or 3 d had greater luminal mucin and jejunum Muc2 expression than those fed the control diet. In vitro studies using HT-29MTX cells showed that, of the various fibers studied, only LPC and HPC affected mucin secretion. Finally, Wistar rats were fed the LPC diet with or without neomycin in drinking water for 10 d; neomycin treatment did not compromise the effect of LPC on mucin secretion. We conclude that LPC does not affect the number of goblet cells but can interact directly with the epithelium and stimulate small intestinal mucin secretion.

  13. Modulation of hydrogen sulfide by vascular hypoxia

    Directory of Open Access Journals (Sweden)

    Osmond JM

    2014-08-01

    Full Text Available Jessica M Osmond, Nancy L KanagyVascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, NM, USAAbstract: Hydrogen sulfide (H2S has emerged as a key regulator of cardiovascular function. This gasotransmitter is produced in the vasculature and is involved in numerous processes that promote vascular homeostasis, including vasodilation and endothelial cell proliferation. Although H2S plays a role under physiological conditions, it has become clear in recent years that hypoxia modulates the production and action of H2S. Furthermore, there is growing evidence that H2S is cytoprotective in the face of hypoxic insults. This review focuses on the synthesis and signaling of H2S in hypoxic conditions in the vasculature, and highlights recent studies providing evidence that H2S is a potential therapy for preventing tissue damage in hypoxic conditions.Keywords: H2S, cystathionine γ-lyase, vascular smooth muscle, endothelium

  14. REDD1 Is Essential for Optimal T Cell Proliferation and Survival.

    Directory of Open Access Journals (Sweden)

    Emma L Reuschel

    Full Text Available REDD1 is a highly conserved stress response protein that is upregulated following many types of cellular stress, including hypoxia, DNA damage, energy stress, ER stress, and nutrient deprivation. Recently, REDD1 was shown to be involved in dexamethasone induced autophagy in murine thymocytes. However, we know little of REDD1's function in mature T cells. Here we show for the first time that REDD1 is upregulated following T cell stimulation with PHA or CD3/CD28 beads. REDD1 knockout T cells exhibit a defect in proliferation and cell survival, although markers of activation appear normal. These findings demonstrate a previously unappreciated role for REDD1 in T cell function.

  15. Hypoxia regulates stemness of breast cancer MDA-MB-231 cells.

    Science.gov (United States)

    Xie, Jing; Xiao, Yong; Zhu, Xiao-yan; Ning, Zhou-yu; Xu, Hai-fan; Wu, Hui-min

    2016-05-01

    Human breast cancers include cancer stem cell populations as well as non-tumorigenic cancer cells. Breast cancer stem cells possess self-renewal capability and thus are the root cause of recurrence and metastasis of malignant tumors. Hypoxia is a fundamental pathological feature of solid tumor tissues and exerts a wide range of effects on the biological behavior of cancer cells. However, there is little information on the role of hypoxia in modulating the stemness of breast cancer cells. In the present study, we cultured MDA-MB-231 cells in a hypoxic gas mixture to simulate the hypoxic environment in tissues and to determine how hypoxia conditions could affect the cell proliferation, apoptosis, cytotoxicity, and colony-forming ability. Expression of the stem cell phenotype CD24(-)CD44(+)ESA(+) was analyzed to assess the effects of hypoxia on stemness transformation in MDA-MB-231 cells. Our results found that the cell toxicity of MDA-MB-231 cells was not affected by hypoxia. Hypoxia could slightly inhibit the growth of MDA-MB-231 cells, but the inhibitory effect is not significant when compared with normoxic control. Moreover, hypoxia significantly blocked the apoptosis in MDA-MB-231 cells (P MB-231 cells was increased greatly after they were treated with hypoxia, and cell colony-formation rate of MDA-MB-231 cells also increased significantly in hypoxia-treated cells. These results encourage the exploration of hypoxia as a mechanism which might not be underestimated in chemo-resistant breast cancer treatment.

  16. The Effect of Erigeron Breviscapus on Proliferation of Pulmonary Artery Smooth Muscle Cells in Hypoxic Porcines

    Institute of Scientific and Technical Information of China (English)

    DING; Yipeng; XU; Yongjian; ZHANG; Zhenxiang

    2001-01-01

    In order to study the effect of Erigeron Breviscapus (EB) on proliferation of pulmonary artery smooth muscle cells (PASMC) in hypoxic porcines, immunohistochemical and MTT methods were employed to measure the proliferation of PASMC. It was found that the proliferation of PASMC in porcines was obvious, and the expression of proliferating cell nuclear antigen (PCNA)was significantly high within 48 h after exposure to hypoxia. The EB could inhibit the proliferation and the expression of PCNA in PASMC under hypoxia, but it had no effect on the proliferation and expression of PCNA in PASMC under normal condition. The EB could inhibit the proliferation and the expression of PCNA in PASMC induced by phorbol 12-myristate 13-acetate (PMA), an agonist of PKC in normal and hypoxic conditions. It was concluded that the hypoxia could enhance the proliferation and expression of PCNA in PASMC. The EB can inhibit the proliferation and expression of PCNA in PASMC under hypoxia through PKC-signal way. The EB may be used in treating the pulmonary hypertension by inhibiting the proliferation of PASMC and the pulmonary vascular remodeling.

  17. Multiple across-strain and within-strain QTLs suggest highly complex genetic architecture for hypoxia tolerance in channel catfish.

    Science.gov (United States)

    Wang, Xiaozhu; Liu, Shikai; Jiang, Chen; Geng, Xin; Zhou, Tao; Li, Ning; Bao, Lisui; Li, Yun; Yao, Jun; Yang, Yujia; Zhong, Xiaoxiao; Jin, Yulin; Dunham, Rex; Liu, Zhanjiang

    2017-02-01

    The ability to survive hypoxic conditions is important for various organisms, especially for aquatic animals. Teleost fish, representing more than 50 % of vertebrate species, are extremely efficient in utilizing low levels of dissolved oxygen in water. However, huge variations exist among various taxa of fish in their ability to tolerate hypoxia. In aquaculture, hypoxia tolerance is among the most important traits because hypoxia can cause major economic losses. Genetic enhancement for hypoxia tolerance in catfish is of great interest, but little was done with analysis of the genetic architecture of hypoxia tolerance. The objective of this study was to conduct a genome-wide association study to identify QTLs for hypoxia tolerance using the catfish 250K SNP array with channel catfish families from six strains. Multiple significant and suggestive QTLs were identified across and within strains. One significant QTL and four suggestive QTLs were identified across strains. Six significant QTLs and many suggestive QTLs were identified within strains. There were rare overlaps among the QTLs identified within the six strains, suggesting a complex genetic architecture of hypoxia tolerance. Overall, within-strain QTLs explained larger proportion of phenotypic variation than across-strain QTLs. Many of genes within these identified QTLs have known functions for regulation of oxygen metabolism and involvement in hypoxia responses. Pathway analysis indicated that most of these genes were involved in MAPK or PI3K/AKT/mTOR signaling pathways that were known to be important for hypoxia-mediated angiogenesis, cell proliferation, apoptosis and survival.

  18. Hypoxia during pregnancy in rats leads to the changes of the cerebral white matter in adult offspring

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    Wang, Lingxing; Cai, Ruowei [Department of Neurology, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian (China); Lv, Guorong, E-mail: lxingwan502@gmail.com [Department of Ultrasound, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian (China); Huang, Ziyang; Wang, Zhenhua [Department of Cardiology, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian (China)

    2010-05-28

    The aim of the present study is to evaluate the effect of reduced fetal oxygen supply on cerebral white matter in the adult offspring and further assess its susceptibility to postnatal hypoxia and high-fat diet. Based on a 3 x 2 full factorial design consisting of three factors of maternal hypoxia, postnatal high-fat diet, and postnatal hypoxia, the ultrastructure of myelin, axon and capillaries were observed, and the expression of myelin basic protein (MBP), neurofilament-H+L(NF-H+L), and glial fibrillary acidic protein (GFAP) was analyzed in periventricular white matter of 16-month-old offspring. Demyelination, injured axon and damaged microvasculars were observed in maternal hypoxia offspring. The main effect of maternal hypoxia lead to decreased expression of MBP or NF-H+L, and increased expression of GFAP (all P < 0.05). Moreover, there was positive three-way interaction among maternal hypoxia, high-fat diet and postnatal hypoxia on MBP, NF-H+L or GFAP expression (all P < 0.05). In summary, our results indicated that maternal hypoxia during pregnancy in rats lead to changes of periventricular white matter in adult offspring, including demyelination, damaged axon and proliferated astroglia. This effect was amplified by high-fat diet and postnatal hypoxia.

  19. PRRSV-infected monocyte-derived dendritic cells express high levels of SLA-DR and CD80/86 but do not stimulate PRRSV-naïve regulatory T cells to proliferate.

    Science.gov (United States)

    Rodríguez-Gómez, Irene M; Käser, Tobias; Gómez-Laguna, Jaime; Lamp, Benjamin; Sinn, Leonie; Rümenapf, Till; Carrasco, Librado; Saalmüller, Armin; Gerner, Wilhelm

    2015-05-20

    In vitro generated monocyte-derived dendritic cells (moDCs) have frequently been used to study the influence of porcine reproductive and respiratory syndrome virus (PRRSV) infection on antigen presenting cells. However, obtained results have often been conflicting in regard to expression of co-stimulatory molecules and interaction with T cells. In this study we performed a detailed phenotypic characterisation of PRRSV-infected moDCs and non-infected moDCs. For CD163 and CD169, which are involved in PRRSV-entry into host cells, our results show that prior to infection porcine moDCs express high levels of CD163 but only very low levels for CD169. Following infection with either PRRSV-1 or PRRSV-2 strains after 24 h, PRRSV-nucleoprotein (N-protein)(+) and N-protein(-) moDCs derived from the same microculture were analyzed for expression of swine leukocyte antigen-DR (SLA-DR) and CD80/86. N-protein(+) moDCs consistently expressed higher levels of SLA-DR and CD80/86 compared to N-protein(-) moDCs. We also investigated the influence of PRRSV-infected moDCs on proliferation and frequency of Foxp3(+) regulatory T cells present within CD4(+) T cells in in vitro co-cultures. Neither CD3-stimulated nor unstimulated CD4(+) T cells showed differences in regard to proliferation and frequency of Foxp3(+) T cells following co-cultivation with either PRRSV-1 or PRRSV-2 infected moDCs. Our results suggest that a more detailed characterisation of PRRSV-infected moDCs will lead to more consistent results across different laboratories and PRRSV strains as indicated by the major differences in SLA-DR and CD80/86 expression between PRRSV-infected and non-infected moDCs present in the same microculture.

  20. 氧化苦参碱抑制二硝基氟苯所致小鼠接触性皮炎及淋巴细胞增殖%Restraint-effect of Oxymatrine on mouse's allergic contact dermatitis stimulated by DNFB and lymphocyte proliferation stimulated by Con A

    Institute of Scientific and Technical Information of China (English)

    陈明亮; 伍斌; 谢红付; 张江林; 杜乾君; 李建国; 李罗丝

    2006-01-01

    [Objective] To explore the restraint-effect of oxymatrine (OMT)on allergic contact dermatitis (ACD)and lymphocyte proliferation. [Methods] 1.To build up an ACD mouse model stimulated by DNFB and then to perform intraperitoneal injection with different dosages of OMT, PBS and hydrocortisone(HCT), To observe the curative effect by examining the swelling degree of mice auricles. 2. Dyed by Carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE) and then flow cytometer was used to examine the fluorescence intensity changes of lymphocyte co-influenced by polyclonal stimulator Concanavalin A (Con A) and OMT. Whereafter, analyze the efficacy of OMT on mouse lymphocyte proliferation by related software. [Results] 1. Comparing with PBS group, OMT possesses much stronger restraint-effect on ACD that caused by DNFB and depends on its injection dosage. Its restraint-effect is equivalent to the HCT of the same dosage, but brings fewer side effects. 2. In vitro expenment, it proves that OMT has the effects to restrain the proliferation of mice's lymphocyte depending on its concentration in substrate as it behaves differently in group 500, 125 and 31 μg/ml. [Conclusion] OMT possesses the obvious effect of restraining the ACD stimulated by DNFB; OMT is a kind of immunosuppressor.%目的 探讨氧化苦参碱(OMT)对二硝基氟苯(DNFB)所致小鼠变应性接触性皮炎(ACD)的抑制作用及小鼠淋巴细胞增殖的影响.方法 建立DNFB所致小鼠ACD模型,以不同剂量的OMT、PBS、氢化可的松(HCT)进行腹腔注射,检测小鼠耳廓肿胀度变化;利用羧基荧光素乙酰乙酸(CFDA-SE)染色,流式细胞术检测OMT对小鼠淋巴细胞增殖的影响.结果 OMT对DNFB所致小鼠ACD呈剂量依赖性抑制作用,且与同等剂量HCT作用效果相似,但副作用明显减小;体外实验证明,在500、125和31 μg/mL组OMT对小鼠淋巴细胞增殖呈剂量依赖性抑制.结论 OMT对DNFB所致小鼠ACD有显著的抑制作用,而且抑制小鼠淋

  1. Hypoxia-regulated microRNAs in human cancer

    Institute of Scientific and Technical Information of China (English)

    Guomin SHEN; Xiaobo LI; Yong-feng JIA; Gary A PIAZZA; Yaguang XI

    2013-01-01

    Hypoxia plays an important role in the tumor microenvironment by allowing the development and maintenance of cancer cells,but the regulatory mechanisms by which tumor cells adapt to hypoxic conditions are not yet well understood.MicroRNAs are recognized as a new class of master regulators that control gene expression and are responsible for many normal and pathological cellular processes.Studies have shown that hypoxia inducible factor 1 (HIF1) regulates a panel of microRNAs,whereas some of microRNAs target HIF1.The interaction between microRNAs and HIF1 can account for many vital events relevant to tumorigenesis,such as angiogenesis,metabolism,apoptosis,cell cycle regulation,proliferation,metastasis,and resistance to anticancer therapy.This review will summarize recent findings on the roles of hypoxia and microRNAs in human cancer and illustrate the machinery by which microRNAs interact with hypoxia in tumor cells,It is expected to update our knowledge about the regulatory roles of microRNAs in regulating tumor microenvironments and thus benefit the development of new anticancer drugs.

  2. Vaccination of rhesus macaques with the live-attenuated HSV-1 vaccine VC2 stimulates the proliferation of mucosal T cells and germinal center responses resulting in sustained production of highly neutralizing antibodies.

    Science.gov (United States)

    Stanfield, Brent A; Pahar, Bapi; Chouljenko, Vladimir N; Veazey, Ronald; Kousoulas, Konstantin G

    2017-01-23

    We have shown that the live-attenuated HSV-1 VC2 vaccine strain with mutations in glycoprotein K (gK) and the membrane protein UL20 is unable to establish latency in vaccinated animals and produces a robust immune response capable of completely protecting mice against lethal vaginal HSV-1 or HSV-2 infections. To better understand the immune response generated by vaccination with VC2, we tested its ability to elicit immune responses in rhesus macaques. Vaccinated animals showed no signs of disease and developed increasing HSV-1 and HSV-2 reactive IgG1 after two booster vaccinations, while IgG subtypes IgG2 and IgG3 remained at low to undetectable levels. All vaccinated animals produced high levels of cross protective neutralizing antibodies. Flow cytometry analysis of cells isolated from draining lymph nodes showed that VC2 vaccination stimulated significant increases in plasmablast (CD27(high)CD38(high)) and mature memory (CD21(-)IgM(-)) B cells. T cell analysis on cells isolated from draining lymph node biopsies demonstrated a statistically significant increase in proliferating (Ki67(+)) follicular T helper cells and regulatory CXCR5(+) CD8(+) cytotoxic T cells. Analysis of plasma isolated two weeks post vaccination showed significant increases in circulating CXCL13 indicating increased germinal center activity. Cells isolated from vaginal biopsy samples collected over the course of the study exhibited vaccination-dependent increases in proliferating (Ki67(+)) CD4(+) and CD8(+) T cell populations. These results suggest that intramuscular vaccination with the live-attenuated HSV-1 VC2 vaccine strain can stimulate robust IgG1 antibody responses that persist for >250days post vaccination. In addition, vaccination lead to the maturation of B cells into plasmablast and mature memory B cells, the expansion of follicular T helper cells, and affects in the mucosal immune responses. These data suggest that the HSV VC2 vaccine induces potent immune responses that could help

  3. Hypoxia, Monitoring, and Mitigation System

    Science.gov (United States)

    2014-05-01

    al., (2012). Short-term exposure to hypoxia for work and leisure activities in health and disease: which level of hypoxia is safe? Sleep Breath, 16...Altitude Illness. Emergency Medical Clinics of North America. (2):329-55, viii. Travel to a high altitude requires that the human body acclimatize to...preventable. Practitioners working in or advising those traveling to a high altitude must be familiar with the early recognition of symptoms, prompt

  4. Therapeutic efficacy of valproic acid in a combined monocrotaline and chronic hypoxia rat model of severe pulmonary hypertension.

    Directory of Open Access Journals (Sweden)

    Beidi Lan

    Full Text Available Pulmonary hypertension (PH is a serious disease with poor prognosis. Reports show that cells in remodeled pulmonary arteries of PH patients have similar characteristics to cancer cells, such as exuberant inflammation, increased proliferation, and decreased apoptosis. An ideal strategy for developing PH therapies is to directly target pulmonary vascular remodeling. High levels of histone deacetylase (HDAC expression and activity are found in certain cancers, and research has shown the potential of HDAC inhibitors in repressing tumor growth via anti-inflammatory and anti-proliferative effects. To date, little is known about the effectiveness of HDAC inhibitors against pulmonary vascular remodeling in severe PH.To investigate whether class I HDAC inhibitors suppress or reverse the development of severe PH in rats.Male Sprague-Dawley rats were injected with a single, subcutaneous dose of monocrotaline (60 mg/kg, and were exposed to chronic hypoxia to induce severe PH. Valproic acid, a class I HDAC inhibitor, was administered to rats daily via gastric gavage (300 mg/kg in a PH prevention study (during the first 3 weeks or a PH reversal study (from 3 to 5 weeks. At the end of experiment, hemodynamic indices were measured, ventricular hypertrophy indices were calculated and vascular remodeling phenotypes were analyzed.After 3 weeks exposure to a combined stimulation of monocrotaline and chronic hypoxia, rats exhibited a reduced body weight, elevated right ventricular systolic pressure, an increased Fulton index, right ventricle weight ratio, medial wall thickness and muscularized peripheral pulmonary arteries. These parameters for PH evaluation were exacerbated from 3 to 5 weeks. Daily administration of valproic acid therapy prevented and partially reversed the development of severe PH in rats, and decreased inflammation and proliferation in remodeled pulmonary arteries.These data show that class I HDAC inhibitors may be effective for treating severe

  5. Hypoxia, Oxidative Stress and Fat

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    Nikolaus Netzer

    2015-06-01

    Full Text Available Metabolic disturbances in white adipose tissue in obese individuals contribute to the pathogenesis of insulin resistance and the development of type 2 diabetes mellitus. Impaired insulin action in adipocytes is associated with elevated lipolysis and increased free fatty acids leading to ectopic fat deposition in liver and skeletal muscle. Chronic adipose tissue hypoxia has been suggested to be part of pathomechanisms causing dysfunction of adipocytes. Hypoxia can provoke oxidative stress in human and animal adipocytes and reduce the production of beneficial adipokines, such as adiponectin. However, time-dose responses to hypoxia relativize the effects of hypoxic stress. Long-term exposure of fat cells to hypoxia can lead to the production of beneficial substances such as leptin. Knowledge of time-dose responses of hypoxia on white adipose tissue and the time course of generation of oxidative stress in adipocytes is still scarce. This paper reviews the potential links between adipose tissue hypoxia, oxidative stress, mitochondrial dysfunction, and low-grade inflammation caused by adipocyte hypertrophy, macrophage infiltration and production of inflammatory mediators.

  6. IGFBP-3, hypoxia and TNF-{alpha} inhibit adiponectin transcription

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    Zappala, Giovanna, E-mail: zappalag@mail.nih.gov [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Rechler, Matthew M. [Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States); Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD (United States)

    2009-05-15

    The thiazolidinedione rosiglitazone, an agonist ligand for the nuclear receptor PPAR-{gamma}, improves insulin sensitivity in part by stimulating transcription of the insulin-sensitizing adipokine adiponectin. It activates PPAR-{gamma}-RXR-{alpha} heterodimers bound to PPAR-{gamma} response elements in the adiponectin promoter. Rosiglitazone-stimulated adiponectin protein synthesis in 3T3-L1 mouse adipocytes has been shown to be inhibited by IGFBP-3, which can be induced by hypoxia and the proinflammatory cytokine, TNF-{alpha}, two inhibitors of adiponectin transcription. The present study demonstrates that IGFBP-3, the hypoxia-mimetic agent cobalt chloride, and TNF-{alpha} inhibit rosiglitazone-induced adiponectin transcription in mouse embryo fibroblasts that stably express PPAR-{gamma}2. Native IGFBP-3 can bind RXR-{alpha} and inhibited rosiglitazone stimulated promoter activity, whereas an IGFBP-3 mutant that does not bind RXR-{alpha} did not. These results suggest that IGFBP-3 may mediate the inhibition of adiponectin transcription by hypoxia and TNF-{alpha}, and that IGFBP-3 binding to RXR-{alpha} may be required for the observed inhibition.

  7. Short-duration intermittent hypoxia enhances endurance capacity by improving muscle fatty acid metabolism in mice.

    Science.gov (United States)

    Suzuki, Junichi

    2016-04-01

    This study was designed to (1) investigate the effects of acute short-duration intermittent hypoxia on musclemRNAand microRNAexpression levels; and (2) clarify the mechanisms by which short-duration intermittent hypoxia improves endurance capacity. Experiment-1: Male mice were subjected to either acute 1-h hypoxia (12% O2), acute short-duration intermittent hypoxia (12% O2for 15 min, room air for 10 min, 4 times, Int-Hypo), or acute endurance exercise (Ex). The expression of vascular endothelial growth factor-AmRNAwas significantly greater than the control at 0 h post Ex and 6 h post Int-Hypo in the deep red region of the gastrocnemius muscle. miR-16 expression levels were significantly lower at 6 and 10 h post Int-Hypo. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)mRNAlevels were significantly greater than the control at 3 h post Ex and 6 h post Int-Hypo. miR-23a expression levels were lower than the control at 6-24 h post Int-Hypo. Experiment-2: Mice were subjected to normoxic exercise training with or without intermittent hypoxia for 3 weeks. Increases in maximal exercise capacity were significantly greater by training with short-duration intermittent hypoxia (IntTr) than without hypoxia. Both 3-Hydroxyacyl-CoA-dehydrogenase and total carnitine palmitoyl transferase activities were significantly enhanced in IntTr. Peroxisome proliferator-activated receptor delta andPGC-1α mRNAlevels were both significantly greater in IntTr than in the sedentary controls. These results suggest that exercise training under normoxic conditions with exposure to short-duration intermittent hypoxia represents a beneficial strategy for increasing endurance performance by enhancing fatty acid metabolism in skeletal muscle.

  8. Hypobaric intermittent hypoxia attenuates hypoxia-induced depressor response.

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    Fang Cui

    Full Text Available BACKGROUND: Hypobaric intermittent hypoxia (HIH produces many favorable effects in the cardiovascular system such as anti-hypertensive effect. In this study, we showed that HIH significantly attenuated a depressor response induced by acute hypoxia. METHODOLOGY/PRINCIPAL FINDINGS: Sprague-Dawley rats received HIH in a hypobaric chamber simulating an altitude of 5000 m. The artery blood pressure (ABP, heart rate (HR and renal sympathetic nerve activity (RSNA were recorded in anesthetized control rats and rats received HIH. The baseline ABP, HR and RSNA were not different between HIH and control rats. Acute hypoxia-induced decrease in ABP was significantly attenuated in HIH rat compared with control rats. However, acute hypoxia-induced increases in HR and RSNA were greater in HIH rat than in control rats. After removal of bilateral ascending depressor nerves, acute hypoxia-induced depressor and sympathoexcitatory responses were comparable in control and HIH rats. Furthermore, acute hypoxia-induced depressor and sympathoexcitatory responses did not differ between control and HIH groups after blocking ATP-dependent K(+ channels by glibenclamide. The baroreflex function evaluated by intravenous injection of phenylephrine and sodium nitroprusside was markedly augmented in HIH rats compared with control rats. The pressor and sympathoexcitatory responses evoked by intravenous injection of cyanide potassium were also significantly greater in HIH rats than in control rats. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that HIH suppresses acute hypoxia-induced depressor response through enhancement of baroreflex and chemoreflex function, which involves activation of ATP-dependent K(+ channels. This study provides new information and underlying mechanism on the beneficiary effect of HIH on maintaining cardiovascular homeostasis.

  9. The effect of lentiviral vector-mediated RNA interference targeting hypoxia-inducible factor 1α on the uptake of fluorodeoxyglucose ((18)f) in the human pancreatic cancer cell line, patu8988.

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    Fan, Guanglei; Bo, Jingli; Wan, Renming; Peng, Mingya; Luan, Yufen; Deng, Minbin; Xu, Longbao

    2015-05-01

    Hypoxia can stimulate (18)F-fluorodeoxyglucose ((18)F-FDG) uptake in cultured tumor cells. This study has investigated the effect of lentiviral vector-mediated RNA interference (RNAi) targeting hypoxia-inducible factor 1α (HIF-1α) on the changes in HIF-1 and glucose transporter 1 (Glut-1) expression, the cell growth, and the uptake of (18)F-FDG in the human pancreatic cancer cell line, Patu8988. Lentiviral RNAi vector targeting the HIF-1α gene (LV-HIF-1αRNAi) was constructed and used to treat cells at various concentrations (25-200 nM). The expression changes of HIF-1α and Glut-1 in hypoxic Patu8988 cells after RNAi treatment were determined using real time reverse transcription-polymerase chain reaction (real-time PCR). The inhibition rate of cell proliferation 48 hours after the addition of 10 μL of different concentrations of LV-HIF-1αRNAi (25-200 nM) was assayed using the MTT method. Meanwhile, the cell uptake of (18)F-FDG was also assessed. After RNAi transfection, the relative expression levels of HIF-1α mRNA and Glut-1 under hypoxia were reduced and the relative expression levels of HIF-1α protein also decreased. Compared with the control group, the inhibition rates of cell proliferation under different viral dosages were 5.98%, 15.65%, 26.42%, and 40.81%, respectively, positively correlated with the viral doses (r=0.558, p<0.05). Under hypoxia, Glut-1 mRNA expression in Patu8988 cells treated with 200 nM of LV-HIF-1αRNAi for 24, 48, and 72 hours, respectively, was positively correlated with the inhibition rate of cell proliferation (r=0.618, p<0.05) as well as the inhibition rate of (18)F-FDG uptake (r=0.664, p<0.05), while the latter two displayed a positive correlation with each other too (r=0.582, p<0.05). Under hypoxia, RNAi targeting HIF-1α significantly inhibited the expression of Glut-1 mRNA in Patu8988 pancreatic cancer cells and their uptake of (18)F-FDG. These results suggest that LV-HIF-1αRNAi may form a new treatment for

  10. Nampt/PBEF/Visfatin Upregulation in Colorectal Tumors, Mirrored in Normal Tissue and Whole Blood of Colorectal Cancer Patients, Is Associated with Metastasis, Hypoxia, IL1β, and Anemia

    Directory of Open Access Journals (Sweden)

    Katarzyna Neubauer

    2015-01-01

    Full Text Available Targeting Nampt/PBEF/visfatin is considered a promising anticancer strategy, yet little is known about its association with colorectal cancer (CRC. We quantified Nampt/PBEF/visfatin expression in bowel and blood (mRNA and protein, referring it to CRC advancement and inflammatory, angiogenic, hypoxia, and proliferation indices. Tumor Nampt/PBEF/visfatin upregulation was associated with metastasis, anemia, tumor location, HIF1α, and inflammatory and angiogenic indices, of which HIF1α, IL1β, and anemia explained 70% in Nampt/PBEF/visfatin variability. Nampt/PBEF/visfatin expression in nontumor tissue, both mRNA and protein, increased in patients with metastatic disease and mild anemia, and, on transcriptional level, correlated with HIF1α, IL1β, IL8, CCL2, and CCL4 expression. Whole blood Nampt/PBEF/visfatin tended to be elevated in patients with metastatic cancer or anemia and correlated with inflammatory indices, of which IL1β, IL8, and hematocrit explained 60% of its variability. Circulating visfatin was associated with lymph node metastasis and inflammatory and angiogenic indices. In vitro experiments on SW620 cells demonstrated Nampt/PBEF/visfatin downregulation in response to serum withdrawal but its upregulation in response to serum induction and hypoxia. Stimulation with recombinant visfatin did not provide growth advantage. Summarizing, our results link Nampt/PBEF/visfatin with tumor metastatic potential and point at inflammation and hypoxia as key inducers of its upregulation in CRC.

  11. Nampt/PBEF/visfatin upregulation in colorectal tumors, mirrored in normal tissue and whole blood of colorectal cancer patients, is associated with metastasis, hypoxia, IL1β, and anemia.

    Science.gov (United States)

    Neubauer, Katarzyna; Misa, Iwona Bednarz; Diakowska, Dorota; Kapturkiewicz, Bartosz; Gamian, Andrzej; Krzystek-Korpacka, Malgorzata

    2015-01-01

    Targeting Nampt/PBEF/visfatin is considered a promising anticancer strategy, yet little is known about its association with colorectal cancer (CRC). We quantified Nampt/PBEF/visfatin expression in bowel and blood (mRNA and protein), referring it to CRC advancement and inflammatory, angiogenic, hypoxia, and proliferation indices. Tumor Nampt/PBEF/visfatin upregulation was associated with metastasis, anemia, tumor location, HIF1α, and inflammatory and angiogenic indices, of which HIF1α, IL1β, and anemia explained 70% in Nampt/PBEF/visfatin variability. Nampt/PBEF/visfatin expression in nontumor tissue, both mRNA and protein, increased in patients with metastatic disease and mild anemia, and, on transcriptional level, correlated with HIF1α, IL1β, IL8, CCL2, and CCL4 expression. Whole blood Nampt/PBEF/visfatin tended to be elevated in patients with metastatic cancer or anemia and correlated with inflammatory indices, of which IL1β, IL8, and hematocrit explained 60% of its variability. Circulating visfatin was associated with lymph node metastasis and inflammatory and angiogenic indices. In vitro experiments on SW620 cells demonstrated Nampt/PBEF/visfatin downregulation in response to serum withdrawal but its upregulation in response to serum induction and hypoxia. Stimulation with recombinant visfatin did not provide growth advantage. Summarizing, our results link Nampt/PBEF/visfatin with tumor metastatic potential and point at inflammation and hypoxia as key inducers of its upregulation in CRC.

  12. Granulocyte colony-stimulating factor-producing undifferentiated carcinoma of the colon mimicking a pulmonary giant cell carcinoma: a case showing overexpression of CD44 along with highly proliferating nestin-positive tumor vessels.

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    Tajima, Shogo; Waki, Michihiko; Tsuchiya, Tomonori; Hoshi, Shoji

    2014-01-01

    Granulocyte colony-stimulating factor (G-CSF)-producing tumors are known for their aggressive behavior. Only four cases of G-CSF-producing colorectal carcinoma have been previously reported. Herein, we present a case of an undifferentiated carcinoma of the descending colon showing G-CSF production and giant cell carcinoma morphology in a 93-year-old woman. A tumor with a diameter of 80 mm was identified in the descending colon via computed tomography. Descending colectomy was performed involving the abdominal wall where tumor invasion was observed. The white blood cell count, which was elevated before resection, decreased to normal levels after intervention. However, local recurrence at the resected site was detected 39 days after surgery. Upon recurrence, increased white blood cell counts and serum G-CSF were seen. The patient died because of respiratory failure 98 days after colectomy. By using immunohistochemistry, G-CSF expression was detected in tumor cells in the resected specimen, along with overexpression of CD44 and highly proliferating nestin-positive tumor vessels. The poor clinical outcome of this patient is consistent with previous reports that the expression of these three molecules predict poor prognosis. While G-CSF can be a therapeutic target considering its auto/paracrine function to induce tumor growth via the G-CSF receptor, CD44 and nestin may also be possible candidate therapeutic targets. Further studies are required to assess the efficacy of treatments targeting these three molecules.

  13. Boehmeria nivea Stimulates Glucose Uptake by Activating Peroxisome Proliferator-Activated Receptor Gamma in C2C12 Cells and Improves Glucose Intolerance in Mice Fed a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Sung Hee Kim

    2013-01-01

    Full Text Available We examined the antidiabetic property of Boehmeria nivea (L. Gaud. Ethanolic extract of Boehmeria nivea (L. Gaud. (EBN increased the uptake of 2-[N-(nitrobenz-2-oxa-1,3-diazol-4-ylamino]-2-deoxy-d-glucose in C2C12 myotubes. To examine the mechanisms underlying EBN-mediated increase in glucose uptake, we examined the transcriptional activity and expression of peroxisome proliferator-activated receptor gamma (PPAR-γ, a pivotal target for glucose metabolism in C2C12 myotubes. We found that the EBN increased both the transcriptional activity and mRNA expression levels of PPAR-γ. In addition, we measured phosphorylation and expression levels of other targets of glucose metabolism, such as AMP-activated protein kinase (AMPK and protein kinase B (Akt/PKB. We found that EBN did not alter the phosphorylation or expression levels of these proteins in a time- or dose-dependent manner, which suggested that EBN stimulates glucose uptake through a PPAR-γ-dependent mechanism. Further, we investigated the antidiabetic property of EBN using mice fed a high-fat diet (HFD. Administration of 0.5% EBN reduced the HFD-induced increase in body weight, total cholesterol level, and fatty liver and improved the impaired fasting glucose level, blood insulin content, and glucose intolerance. These results suggest that EBN had an antidiabetic effect in cell culture and animal systems and may be useful for preventing diabetes.

  14. PHD2: from hypoxia regulation to disease progression.

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    Meneses, Ana M; Wielockx, Ben

    2016-01-01

    Oxygen represents one of the major molecules required for the development and maintenance of life. An adequate response to hypoxia is therefore required for the functioning of the majority of living organisms and relies on the activation of the hypoxia-inducible factor (HIF) pathway. HIF prolyl hydroxylase domain-2 (PHD2) has long been recognized as the major regulator of this response, controlling a myriad of outcomes that range from cell death to proliferation. However, this enzyme has been associated with more pathways, making the role of this protein remarkably complex under distinct pathologies. While a protective role seems to exist in physiological conditions such as erythropoiesis; the picture is more complex during pathologies such as cancer. Since the regulation of this enzyme and its closest family members is currently considered as a possible therapy for various diseases, understanding the different particular roles of this protein is essential.

  15. Snail/beta-catenin signaling protects breast cancer cells from hypoxia attack

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    Scherbakov, Alexander M., E-mail: alex.scherbakov@gmail.com [Laboratory of Clinical Biochemistry, Institute of Clinical Oncology, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation); Stefanova, Lidia B.; Sorokin, Danila V.; Semina, Svetlana E. [Laboratory of Molecular Endocrinology, Institute of Carcinogenesis, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation); Berstein, Lev M. [Laboratory of Oncoendocrinology, N.N. Petrov Research Institute of Oncology, St. Petersburg 197758 (Russian Federation); Krasil’nikov, Mikhail A. [Laboratory of Molecular Endocrinology, Institute of Carcinogenesis, N.N. Blokhin Cancer Research Centre, Kashirskoye sh. 24, Moscow 115478 (Russian Federation)

    2013-12-10

    The tolerance of cancer cells to hypoxia depends on the combination of different factors – from increase of glycolysis (Warburg Effect) to activation of intracellular growth/apoptotic pathways. Less is known about the influence of epithelial–mesenchymal transition (EMT) and EMT-associated pathways on the cell sensitivity to hypoxia. The aim of this study was to explore the role of Snail signaling, one of the key EMT pathways, in the mediating of hypoxia response and regulation of cell sensitivity to hypoxia, using as a model in vitro cultured breast cancer cells. Earlier we have shown that estrogen-independent HBL-100 breast cancer cells differ from estrogen-dependent MCF-7 cells with increased expression of Snail1, and demonstrated Snail1 involvement into formation of hormone-resistant phenotype. Because Snail1 belongs to hypoxia-activated proteins, here we studied the influence of Snail1 signaling on the cell tolerance to hypoxia. We found that Snail1-enriched HBL-100 cells were less sensitive to hypoxia-induced growth suppression if compared with MCF-7 line (31% MCF-7 vs. 71% HBL-100 cell viability after 1% O{sub 2} atmosphere for 3 days). Snail1 knock-down enhanced the hypoxia-induced inhibition of cell proliferation giving the direct evidence of Snail1 involvement into cell protection from hypoxia attack. The protective effect of Snail1 was shown to be mediated, at least in a part, via beta-catenin which positively regulated expression of HIF-1-dependent genes. Finally, we found that cell tolerance to hypoxia was accompanied with the failure in the phosphorylation of AMPK – the key energy sensor, and demonstrated an inverse relationship between AMPK and Snail/beta-catenin signaling. Totally, our data show that Snail1 and beta-catenin, besides association with loss of hormone dependence, protect cancer cells from hypoxia and may serve as an important target in the treatment of breast cancer. Moreover, we suggest that the level of these proteins as well

  16. Hypoxia Promotes Osteogenesis of Human Placental-Derived Mesenchymal Stem Cells.

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    Gu, Qiaoli; Gu, Yanzheng; Shi, Qin; Yang, Huilin

    2016-08-01

    Placental-derived mesenchymal stem cells (pMSCs) are promising candidates for regenerative medicine because they possess high proliferative capacity and multi-differentiation potential. Human pMSCs are residing in an environment with low oxygen tension in the body. Heme oxygenase-1 (HO-1) is known to participate in the regulation of MSC differentiation. The present study aimed to investigate the impact of hypoxia on the osteogenic differentiation of human pMSCs, and to elucidate the role of HO-1 in the osteogenic differentiation of hypoxic pMSCs. Human pMSCs were cultured under normoxia (21% O2) or hypoxia (5% O2) for 3 days. We found that hypoxia maintained the morphology and immunophenotype of human pMSCs. The expression of stemness markers Oct4, Nanog, and Sox2 was increased under hypoxia. After a 5-day hypoxic culture, the proliferation ability of pMSCs was increased, which might be correlated with the increased expression of stem cell factor. During osteogenic induction, hypoxia increased the expression of osteogenic genes including osteopontin, osteocalcin, and alkaline phosphatase (ALP). Moreover, hypoxia increased the mineralization and ALP levels of human pMSCs as evidenced by Alizarin Red staining and ALP staining. Upregulation of HO-1 by cobalt-protoporphyrin treatment increased the osteogenic differentiation of pMSCs under hypoxia, while inhibition of HO-1 by Zn-protoporphyrin reduced the osteogenic differentiation of hypoxic pMSCs. Taken together, our data suggest that hypoxia can promote the osteogenic differentiation of human pMSCs. Upregulation of HO-1 can further increase the osteogenesis of human pMSCs under hypoxia. Our findings will highlight the therapeutic potential of MSCs in the tissue engineering of bones.

  17. Maternal hypoxia alters matrix metalloproteinase expression patterns and causes cardiac remodeling in fetal and neonatal rats.

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    Tong, Wenni; Xue, Qin; Li, Yong; Zhang, Lubo

    2011-11-01

    Fetal hypoxia leads to progressive cardiac remodeling in rat offspring. The present study tested the hypothesis that maternal hypoxia results in reprogramming of matrix metalloproteinase (MMP) expression patterns and fibrillar collagen matrix in the developing heart. Pregnant rats were treated with normoxia or hypoxia (10.5% O(2)) from day 15 to 21 of gestation. Hearts were isolated from 21-day fetuses (E21) and postnatal day 7 pups (PD7). Maternal hypoxia caused a decrease in the body weight of both E21 and PD7. The heart-to-body weight ratio was increased in E21 but not in PD7. Left ventricular myocardium wall thickness and cardiomyocyte proliferation were significantly decreased in both fetal and neonatal hearts. Hypoxia had no effect on fibrillar collagen content in the fetal heart, but significantly increased the collagen content in the neonatal heart. Western blotting revealed that maternal hypoxia significantly increased collagen I, but not collagen III, levels in the neonatal heart. Maternal hypoxia decreased MMP-1 but increased MMP-13 and membrane type (MT)1-MMP in the fetal heart. In the neonatal heart, MMP-1 and MMP-13 were significantly increased. Active MMP-2 and MMP-9 levels and activities were not altered in either fetal or neonatal hearts. Hypoxia significantly increased tissue inhibitors of metalloproteinase (TIMP)-3 and TIMP-4 in both fetal and neonatal hearts. In contrast, TIMP-1 and TIMP-2 were not affected. The results demonstrate that in utero hypoxia reprograms the expression patterns of MMPs and TIMPs and causes cardiac tissue remodeling with the increased collagen deposition in the developing heart.

  18. Hypoxia induces heart regeneration in adult mice.

    Science.gov (United States)

    Nakada, Yuji; Canseco, Diana C; Thet, SuWannee; Abdisalaam, Salim; Asaithamby, Aroumougame; Santos, Celio X; Shah, Ajay M; Zhang, Hua; Faber, James E; Kinter, Michael T; Szweda, Luke I; Xing, Chao; Hu, Zeping; Deberardinis, Ralph J; Schiattarella, Gabriele; Hill, Joseph A; Oz, Orhan; Lu, Zhigang; Zhang, Cheng Cheng; Kimura, Wataru; Sadek, Hesham A

    2017-01-12

    The adult mammalian heart is incapable of regeneration following cardiomyocyte loss, which underpins the lasting and severe effects of cardiomyopathy. Recently, it has become clear that the mammalian heart is not a post-mitotic organ. For example, the neonatal heart is capable of regenerating lost myocardium, and the adult heart is capable of modest self-renewal. In both of these scenarios, cardiomyocyte renewal occurs via the proliferation of pre-existing cardiomyocytes, and is regulated by aerobic-respiration-mediated oxidative DNA damage. Therefore, we reasoned that inhibiting aerobic respiration by inducing systemic hypoxaemia would alleviate oxidative DNA damage, thereby inducing cardiomyocyte proliferation in adult mammals. Here we report that, in mice, gradual exposure to severe systemic hypoxaemia, in which inspired oxygen is gradually decreased by 1% and maintained at 7% for 2 weeks, results in inhibition of oxidative metabolism, decreased reactive oxygen species production and oxidative DNA damage, and reactivation of cardiomyocyte mitosis. Notably, we find that exposure to hypoxaemia 1 week after induction of myocardial infarction induces a robust regenerative response with decreased myocardial fibrosis and improvement of left ventricular systolic function. Genetic fate-mapping analysis confirms that the newly formed myocardium is derived from pre-existing cardiomyocytes. These results demonstrate that the endogenous regenerative properties of the adult mammalian heart can be reactivated by exposure to gradual systemic hypoxaemia, and highlight the potential therapeutic role of hypoxia in regenerative medicine.

  19. Low Molecular Weight Fucoidan Inhibits Tumor Angiogenesis through Downregulation of HIF-1/VEGF Signaling under Hypoxia

    Directory of Open Access Journals (Sweden)

    Meng-Chuan Chen

    2015-07-01

    Full Text Available Activation of hypoxia-induced hypoxia-inducible factors-1 (HIF-1 plays a critical role in promoting tumor angiogenesis, growth and metastasis. Low molecular weight fucoidan (LMWF is prepared from brown algae, and exhibits anticancer activity. However, whether LMWF attenuates hypoxia-induced angiogenesis in bladder cancer cells and the molecular mechanisms involved remain unclear. This is the first study to demonstrate that LMWF can inhibit hypoxia-stimulated H2O2 formation, HIF-1 accumulation and transcriptional activity vascular endothelial growth factor (VEGF secretion, and the migration and invasion in hypoxic human bladder cancer cells (T24 cells. LMWF also downregulated hypoxia-activated phosphorylation of PI3K/AKT/mTOR/p70S6K/4EBP-1 signaling in T24 cells. Blocking PI3K/AKT or mTOR activity strongly diminished hypoxia-induced HIF-1α expression and VEGF secretion in T24 cells, supporting the involvement of PI3K/AKT/mTOR in the induction of HIF-1α and VEGF. Additionally, LMWF significantly attenuated angiogenesis in vitro and in vivo evidenced by reduction of tube formation of hypoxic human umbilical vascular endothelial cells and blood capillary generation in the tumor. Similarly, administration of LMWF also inhibited the HIF-1α and VEGF expression in vivo, accompanied by a reduction of tumor growth. In summary, under hypoxia conditions, the antiangiogenic activity of LMWF in bladder cancer may be associated with suppressing HIF-1/VEGF-regulated signaling pathway.

  20. Lung Oxidative Damage by Hypoxia

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    O. F. Araneda

    2012-01-01

    Full Text Available One of the most important functions of lungs is to maintain an adequate oxygenation in the organism. This organ can be affected by hypoxia facing both physiological and pathological situations. Exposure to this condition favors the increase of reactive oxygen species from mitochondria, as from NADPH oxidase, xanthine oxidase/reductase, and nitric oxide synthase enzymes, as well as establishing an inflammatory process. In lungs, hypoxia also modifies the levels of antioxidant substances causing pulmonary oxidative damage. Imbalance of redox state in lungs induced by hypoxia has been suggested as a participant in the changes observed in lung function in the hypoxic context, such as hypoxic vasoconstriction and pulmonary edema, in addition to vascular remodeling and chronic pulmonary hypertension. In this work, experimental evidence that shows the implied mechanisms in pulmonary redox state by hypoxia is reviewed. Herein, studies of cultures of different lung cells and complete isolated lung and tests conducted in vivo in the different forms of hypoxia, conducted in both animal models and humans, are described.

  1. Lung Oxidative Damage by Hypoxia

    Science.gov (United States)

    Araneda, O. F.; Tuesta, M.

    2012-01-01

    One of the most important functions of lungs is to maintain an adequate oxygenation in the organism. This organ can be affected by hypoxia facing both physiological and pathological situations. Exposure to this condition favors the increase of reactive oxygen species from mitochondria, as from NADPH oxidase, xanthine oxidase/reductase, and nitric oxide synthase enzymes, as well as establishing an inflammatory process. In lungs, hypoxia also modifies the levels of antioxidant substances causing pulmonary oxidative damage. Imbalance of redox state in lungs induced by hypoxia has been suggested as a participant in the changes observed in lung function in the hypoxic context, such as hypoxic vasoconstriction and pulmonary edema, in addition to vascular remodeling and chronic pulmonary hypertension. In this work, experimental evidence that shows the implied mechanisms in pulmonary redox state by hypoxia is reviewed. Herein, studies of cultures of different lung cells and complete isolated lung and tests conducted in vivo in the different forms of hypoxia, conducted in both animal models and humans, are described. PMID:22966417

  2. Hypoxia-Independent Downregulation of Hypoxia-Inducible Factor 1 Targets by Androgen Deprivation Therapy in Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ragnum, Harald Bull [Department of Radiation Biology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Røe, Kathrine [Department of Radiation Biology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Division of Medicine, Department of Oncology, Akershus University Hospital, Lørenskog (Norway); Holm, Ruth; Vlatkovic, Ljiljana [Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Nesland, Jahn Marthin [Department of Pathology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Medical Faculty, University of Oslo, Oslo (Norway); Aarnes, Eva-Katrine [Department of Radiation Biology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Ree, Anne Hansen [Division of Medicine, Department of Oncology, Akershus University Hospital, Lørenskog (Norway); Medical Faculty, University of Oslo, Oslo (Norway); Flatmark, Kjersti [Department of Tumor Biology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Department of Gastrointestinal Surgery, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Seierstad, Therese [Department of Radiology and Nuclear Medicine, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Faculty of Health Sciences, Buskerud University College, Drammen (Norway); Lilleby, Wolfgang [Department of Oncology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway); Lyng, Heidi, E-mail: heidi.lyng@rr-research.no [Department of Radiation Biology, The Norwegian Radium Hospital, Oslo University Hospital, Oslo (Norway)

    2013-11-15

    Purpose: We explored changes in hypoxia-inducible factor 1 (HIF1) signaling during androgen deprivation therapy (ADT) of androgen-sensitive prostate cancer xenografts under conditions in which no significant change in immunostaining of the hypoxia marker pimonidazole had occurred. Methods and Materials: Gene expression profiles of volume-matched androgen-exposed and androgen-deprived CWR22 xenografts, with similar pimonidazole-positive fractions, were compared. Direct targets of androgen receptor (AR) and HIF1 transcription factors were identified among the differentially expressed genes by using published lists. Biological processes affected by ADT were determined by gene ontology analysis. HIF1α protein expression in xenografts and biopsy samples from 35 patients receiving neoadjuvant ADT was assessed by immunohistochemistry. Results: A total of 1344 genes showed more than 2-fold change in expression by ADT, including 35 downregulated and 5 upregulated HIF1 targets. Six genes were shared HIF1 and AR targets, and their downregulation was confirmed with quantitative RT-PCR. Significant suppression of the biological processes proliferation, metabolism, and stress response in androgen-deprived xenografts was found, consistent with tumor regression. Nineteen downregulated HIF1 targets were involved in those significant biological processes, most of them in metabolism. Four of these were shared AR and HIF1 targets, including genes encoding the regulatory glycolytic proteins HK2, PFKFB3, and SLC2A1. Most of the downregulated HIF1 targets were induced by hypoxia in androgen-responsive prostate cancer cell lines, confirming their role as hypoxia-responsive HIF1 targets in prostate cancer. Downregulation of HIF1 targets was consistent with the absence of HIF1α protein in xenografts and downregulation in patients by ADT (P<.001). Conclusions: AR repression by ADT may lead to downregulation of HIF1 signaling independently of hypoxic fraction, and this may contribute to

  3. Hypoxia in the changing marine environment

    Digital Repository Service at National Institute of Oceanography (India)

    Zhang, J.; Cowie, G.; Naqvi, S.W.A.

    of ecosystems from tropics to high latitudes. Among the various associated phenomena of ecosystem deterioration, hypoxia can cause serious problems in coastal areas as well as oxygen minimum zones in the open ocean. The negative impacts of hypoxia include...

  4. Chronic hypoxia in pregnancy affects thymus development in Balb/c mouse offspring via IL2 Signaling.

    Science.gov (United States)

    Zhang, Xiaopeng; Zhou, Xiuwen; Li, Lingjun; Sun, Mi