Gil Mi Na, Choi Du Ri, Yu Kwang Sik, Jeong Ji Heun, Bak Dong-Ho, Kim Do-Kyung, Lee Nam-Seob, Lee Je-Hun, Jeong Young-Gil, Na Chun Soo, Na Dae Seung, Ryu Ki-Hyun, Han Seung Yun
Department of Anatomy, Konyang University College of Medicine, Daejeon, Korea.
Department of Dermatology, Chung-Ang University R&D Center, Seoul, Korea.
Anat Cell Biol. 2016 Sep;49(3):189-198. doi: 10.5115/acb.2016.49.3.189. Epub 2016 Sep 29.
Cholestatic liver cirrhosis (CLC) eventually proceeds to end-stage liver failure by mediating overwhelming deposition of collagen, which is produced by activated interstitial myofibroblasts. Although the beneficial effects of Stokes (RVS) on various diseases are well-known, its therapeutic effect and possible underlying mechanism on interstitial fibrosis associated with CLC are not elucidated. This study was designed to assess the protective effects of RVS and its possible underlying mechanisms in rat models of CLC established by bile duct ligation (BDL). We demonstrated that BDL markedly elevated the serological parameters such as aspartate aminotransferase, alanine transaminase, total bilirubin, and direct bilirubin, all of which were significantly attenuated by the daily uptake of RVS (2 mg/kg/day) for 28 days (14 days before and after operation) via intragastric route. We observed that BDL drastically induced the deterioration of liver histoarchitecture and excessive deposition of extracellular matrix (ECM), both of which were significantly attenuated by RVS. In addition, we revealed that RVS inhibited BDL-induced proliferation and activation of interstitial myofibroblasts, a highly suggestive cell type for ECM production, as shown by immunohistochemical and semi-quantitative detection of α-smooth muscle actin and vimentin. Finally, we demonstrated that the anti-fibrotic effect of RVS was associated with the inactivation of Smad3, the key downstream target of a major fibrogenic cytokine, i.e., transforming growth factor β (TGF-β). Simultaneously, we also found that RVS reciprocally increased the expression of Smad7, a negative regulatory protein of the TGF-β/Smad3 pathway. Taken together, these results suggested that RVS has a therapeutic effect on CLC, and these effects are, at least partly, due to the inhibition of liver fibrosis by the downregulation of Smad3 and upregulation of Smad7.
胆汁淤积性肝硬化（CLC）最终会通过介导由活化的间质肌成纤维细胞产生的大量胶原蛋白沉积而发展为终末期肝衰竭。尽管斯托克斯（RVS）对各种疾病的有益作用已广为人知，但其对与CLC相关的间质纤维化的治疗效果及潜在机制尚未阐明。本研究旨在评估RVS在胆管结扎（BDL）建立的大鼠CLC模型中的保护作用及其潜在机制。我们证明，BDL显著升高了血清学参数，如天冬氨酸转氨酶、丙氨酸转氨酶、总胆红素和直接胆红素，而通过胃内途径每日摄取RVS（2mg/kg/天）持续28天（手术前后各14天）可使所有这些参数显著降低。我们观察到，BDL显著导致肝脏组织结构恶化和细胞外基质（ECM）过度沉积，而RVS均使其显著减轻。此外，通过免疫组织化学和α-平滑肌肌动蛋白及波形蛋白的半定量检测显示，RVS抑制了BDL诱导的间质肌成纤维细胞的增殖和活化，间质肌成纤维细胞是产生ECM的一种极具提示性的细胞类型。最后，我们证明RVS的抗纤维化作用与主要促纤维化细胞因子即转化生长因子β（TGF-β）的关键下游靶点Smad3的失活有关。同时，我们还发现RVS相应地增加了TGF-β/Smad3途径的负调节蛋白Smad7的表达。综上所述，这些结果表明RVS对CLC具有治疗作用，且这些作用至少部分归因于通过下调Smad3和上调Smad7来抑制肝纤维化。
