Effects of salvianolic acid B on signal transduction induced by transforming growth factor-beta1 and platelet-derived growth factor- BB in hepatic stellate cells of rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the anti-hepatic fibrosis mechanisms of salvianolic acid B (SA-B).</p><p><b>METHODS</b>Hepatic stellate cells (HSCs) isolated from rats were primarily cultured in uncoated plastic culture dish for 7 days, then were incubated with 10(-6) mmol/L SA-B and stimulated with 10 ng/ml transforming growth factor-beta1 (TGF-beta1) or platelet-derived growth factor-BB (PDGF-BB). Expressions of extracellular-regulated kinase (ERK) and its phosphorylation in HSC, and expressions of TGF beta1, receptor I (TbetaR I) and II (TbetaR II) and PDGF receptor beta (PDGFR-beta) on the surface of HSC induced by TGF-beta1 or PDGF-BB were detected with Western blot assay.</p><p><b>RESULTS</b>SA-B inhibited the phosphorylation of ERK1/2 in HSC primary normally cultivated for 9 days stimulated or un-stimulated by TGF-beta1, but could not affect the expressions of TbetaR I and TbetaR II on the HSC surface; it down-regulated the expression of PDGFR-beta, but had no obvious effect on the phosphorylation of ERK1/2 in those HSC stimulated or un-stimulated by PDGF-BB.</p><p><b>CONCLUSION</b>SA-B inhibits the ERK signal transduction induced by TGF-beta1 in HSC, which is independent of the expressions of TbetaR on HSC surface and also free from the ERK signal transduction stimulated by PDGF-BB. And its inhibition on PDGF-BB signal transduction in HSC is by way of restraining the expression of PDGFR in HSC.</p>

Salianic-acid B inhibits MAPK signaling in activated rat hepatic stellate cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the inhibiting effect of salianic-acid B (SA-B) on mitogen-activated protein kinase (MAPK) Signaling in activated rat hepatic stellate cells (HSCs).</p><p><b>METHODS</b>HSCs were isolated from normal rat by in situ perfusion and Nycodenz density-gradient centrifugation method. HSCs were primarily cultured on uncoated plastic for 7 days. Then cells were stimulated with 10ng/ml transforming growth factor-beta1 (TGF-beta1) after incubated with 10-6 M/L SA-B. The effects of SA-B on Extracellular-regulated kinase (ERK) expression and its phosphorylation. Transforming growth factor beta1 receptor I (TbetaR I) and transforming growth factor beta1 receptor II (TbetaR II) on HSCs, type I collagen expression in HSC Induced by TGF-beta1 were detected with western blot assay. Quantity of Type I collagen in the medium of HSCs was detected by ELISA. Matrix metalloproteinase 2, 9, 13 (MMP-2, MMP-9 and MMP-13) in the medium of HSCs was tested by Zymography.</p><p><b>RESULTS</b>The phosphorylation of ERK1/2 in HSCs with or without TGF-beta1 was inhibited by SA-B. The expression of TbetaR I and TbetaR II on HSCs can not be affected by SA-B. The synthesization of Type I collagen in HSCs was decreased by SA-B; The synthesization and secretion of type I collagen in HSCs with TGF-beta1 were reduced by SA-B too. SA-B had no effect on the activity of MMP-2 and MMP-13, but induced the activity of MMP-13.</p><p><b>CONCLUSION</b>SA-B inhibits ERK signaling induced by TGF-b1 in HSC. This inhibition has no association with the expression of TbetaR I and TbetaR II on HSCs. SA-B reduces the synthesization and secretion of Type I collagen in HSC by means of inhibiting TGF-beta1 signaling, which might be not related to the degrading activities of MMPs.</p>