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Aim To investigate the mechanism of Pi- ezol in the phenotypic changes of rat coronary arterial smooth muscle cells ( CASMCs) induced by high hydrostatic pressure.Methods CASMCs were isolated from Wistar rats and stimulated for 24 h at 0, 120 and 180 mmHg, respectively.The expressions of Piezol , contractile phenotvpe-related proteins including Cavl.2 ,SM-MHC ,cx-SMA and synthetic phenotvpe-re- lated proteins including OPN , MMP-2, Coll al were detected by Western blot.The effect of calcium influx mediated by Piezol was detected by Laser confocal mi- j j croscopy.CASMCs were treated with Piezol agonist Yodal , inhibitor GsMTx4 and Piezol-siHNA , respectively and the expressions of contractile phenotvpe and synthetic phenotvpe-related proteins were detected by Western blot.Results Compared with control ( 0 mmHg) , the expressions of Piezol , OPN, MMP-2 and Collal increased, but the expressions of Cavl.2,SM- MHC and cx-SMA decreased in 120 mmHg as well as 180 mmHg group.After stimulated by 180 mmHg high pressure, Piezol-mediated calcium influx was stronger than that in 0 mmHg group, hut decreased after Piezol knockdown.Treated with Yodal at 0 mmHg, the expression of contractile phenotvpe-related protein decreased while the expression of synthetic phenotvpe-re- lated protein increased compared with DMSO group..\Jfter using GsMTx4 to inhibit or siRNA to knockdown Piezol at 180 mmHg,the expression of contractile phe- notvpe-related protein increased and the expression of synthetic phenotype-related protein decreased compared with the control group.Conclusion Piezol promotes the transition from contractile phenotvpe to syn-thetic phenotvpe of CASMCs induced by high hydrostatic pressure.
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Objective To investigate the effect of different concentration of uric acid on proliferation and phentyic change of HBZY-1 cells in vitro. Methods The morphological change of HBZY-1 cells exposed to uric acid was observed under the inverted microscope and transmission electronmicroscope. MTT bioassay was used to assess the effect of uric acid on the proliferation of HBZY-1 cell. ELISA method was used to assess the level of angiotensin Ⅱ in HBZY-1 cell incubated with different concentration of uric acid for different treatment duration.The protein and mRNA expression of α-smooth muscle actin (α-SMA) , transforming growth factor-β1 (TGF-β1) and fibronectin in HBZY-1 cells was measured by Western blot and RT-PCR assay, respectively. Results Uric acid (0.4 mmol/L, 24 h) could induce phentypic change of messangial cell from triangle to fibroblast-like morphology.Uric acid could significantly stimulate the proliferation of HBZY-1 cells for 24 h in a concentration-dependent manner (P < 0.05). Uric acid could stimulate the secration of angiotensin Ⅱ in a dose-and time-dependent manner.RT-PCR and Western blot results showed that the markers of myofibroblast transdifferentiation, including a-smooth muscle actin (α-SMA) , transforming growth factor-β1 (TGF-β1) and fibronectin, were significantly upregulated in HBZY-1 cell treated with over 0.1 mmol/L uric acid for 48 h compared with the control group (P < 0.05, respectively). Conclusion Uric acid can induce the proliferation and phentypic change of HBZY-1 in vitro.
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Objective To study the role of endoplasmic reticulum stress in phenotypic change of cultured human glomerular mesangial cells induced by high glucose.Methods Cultured human glomeruar mesangial cells were divided into three groups: control group,high glucose group and high glucose+ 4-phenylbutyric acid (4-PBA) group.Cell number of proliferation was assessed by MTT assay.Cell cycle was measured by flow cytometric analysis.Expression of α-SMA was assessed by immunohistochemistry and was observed by laser scanning confocal microscope.Involved mRNA and protein expression were measured by real-time PCR and Western blotting.Results (1)Cell number of proliferation and S transition proportion in high glucose group significantly increased than that in control group (P ＜ 0.05).High glucose could induce α-SMA expression significantly (P＜0.05).4-PBA could significantly inhibit human glomerular mesangial cells proliferation (P＜0.05),S transition arrest (P＜0.05) and expression of α-SMA (P＜0.05) induced by high glucose.(2) Compared with control group,high glucose could significantly increase the expression of glucose-regulated protein78(Grp78 ) mRNA and protein (P＜ 0.05),which could be inhibited by 4-PBA treatment (P＜0.05).(3)High glucose could induce the mRNA and protein expression of TGF-β1 and FN significantly,which could be inhibited by 4-PBA treatment (P＜0.05).Conclusion Endoplasmic reticulum stress plays an important role in phenotypic change of cultured human glomerular mesangial cells induced by high glucose.