Department of Internal Medicine I, University of Bonn, Bonn, Germany.
Lab Invest. 2012 Oct;92(10):1440-50. doi: 10.1038/labinvest.2012.106. Epub 2012 Aug 13.
Hepatic myofibroblasts (MFB) show increased proliferation, migration and collagen production, which are crucial for hepatic fibrogenesis. Atorvastatin treatment inhibits proliferation, apoptosis and cytokine production of MFB in bile duct-ligated (BDL) rats in vivo. Here, we have further investigated the underlying mechanisms. Primary rat hepatic stellate cells (HSC) were isolated and culture-activated to hepatic MFB. Following 3 days of incubation with atorvastatin (10(-4), 10(-5) and 10(-6) M), transcription levels of profibrotic cytokines (transforming growth factor-β1, connective tissue growth factor and TIMP1) and procollagen Ia were analyzed by real time PCR. Proliferation was investigated by 5'-bromo-2'-deoxyuridine assays. α-Smooth muscle actin protein expression was examined by western blotting. Fluorescence-activated cell sorting analysis of Annexin V and propidium iodide were used to measure apoptosis. Furthermore, p21 western blotting and β-galactosidase staining were investigated in MFB as senescence markers. Subsequently, hepatic expression of desmin and senescence markers were analyzed in the livers of rats receiving atorvastatin (15 mg/kg*d) for 1 week starting 3 and 5 weeks after BDL. Atorvastatin inhibited the activation of HSC to MFB and decreased cytokine and collagen production in MFB in vitro. In addition, proliferation, cytokine and collagen production of MFB were reduced by atorvastatin. Atorvastatin initiated apoptosis at 10(-4) M and attenuated it at 10(-5) M. Atorvastatin induced p21 protein expression and β-galactosidase staining of MFB in vitro and in vivo. Atorvastatin elicits similiar effects on MFB as previously seen in vivo: it decreases MFB turnover and fibrogenesis. We suggest that a further mechanism explaining these effects is senescence of cells.
肝星状细胞（HSC）向肝肌成纤维细胞（MFB）的转化过程中，MFB 表现出增殖、迁移和胶原产生增加，这对于肝纤维化的发生至关重要。阿托伐他汀在体内通过抑制胆管结扎（BDL）大鼠 MFB 的增殖、凋亡和细胞因子产生来发挥作用。在此，我们进一步研究了其潜在的机制。原代大鼠肝星状细胞（HSC）分离并培养激活为肝 MFB。阿托伐他汀孵育 3 天后（10（-4）、10（-5）和 10（-6）M），通过实时 PCR 分析促纤维化细胞因子（转化生长因子-β1、结缔组织生长因子和 TIMP1）和前胶原 Iα的转录水平。通过 5'-溴-2'-脱氧尿苷测定法研究增殖。通过 Western blot 检测α-平滑肌肌动蛋白蛋白表达。使用 Annexin V 和碘化丙啶荧光激活细胞分选分析测量凋亡。此外，还研究了 MFB 中的 p21 Western blot 和β-半乳糖苷酶染色作为衰老标志物。随后，在接受阿托伐他汀（15 mg/kg*d）治疗 1 周后，分析了 BDL 后 3 周和 5 周开始时大鼠肝脏中的 desmin 和衰老标志物的表达。阿托伐他汀抑制 HSC 向 MFB 的激活，并减少 MFB 中的细胞因子和胶原产生。此外，阿托伐他汀还降低了 MFB 的增殖、细胞因子和胶原产生。阿托伐他汀在 10（-4）M 时引发凋亡，在 10（-5）M 时减弱凋亡。阿托伐他汀诱导 MFB 中 p21 蛋白表达和β-半乳糖苷酶染色，无论是在体外还是在体内。阿托伐他汀对 MFB 的作用类似于之前在体内观察到的作用：它降低了 MFB 的转化和纤维化。我们认为，解释这些作用的另一个机制是细胞衰老。
