Department of Pharmacy, College of Medicine, Jiaxing University, Jiaxing, 314001, China.
School of Biology and Food Engineering, Changshu Institute of Technology, Changshu, 215500, China.
J Ethnopharmacol. 2020 Aug 10;258:112813. doi: 10.1016/j.jep.2020.112813. Epub 2020 Apr 4.
Chemical hepatotoxicity, especially alcoholic liver injury (ALI), commonly occurs in young and middle-aged people who drink heavily. ALI is extremely harmful and can induce severe disease states, such as hepatitis, liver fibrosis, cirrhosis, or liver cancer, which are similar to CCl-induced liver disease states in animals. In recent studies, the pathological changes of hepatocytes and the hepatic stellate cell have shown a significant connection between endoplasmic reticulum (ER) stress and the development of liver pathology in patients. However, the detailed pathological mechanism needs to be further studied. Schisandra chinensis, (S. chinensis), a fruit-bearing vine used in Traditional Chinese Medicine (TCM), has been used to treat chronic or acute diseases, including liver disease. S. chinensis-derived lignans (SCDLs) in particular have been shown to alleviate liver pathological changes.
This study sought to elucidate the mechanisms underlying SCDL-mediated hepatoprotection.
We first used in silico target prediction and computational simulation methods to identify putative lignan-binding targets relative to the hepatoprotective effect. A gene microarray analysis was performed to identify differently expressed genes that might have significance in the disease pathological process. We then used histological analyses in a mice hepatotoxicity model to test the effectiveness of SCDLs in vivo, and a hepatocellular toxicity model to analyze the candidate-compound-mediated hepatoprotection and expression states of the key targets in vitro.
The in silico analysis results indicated that endothelin receptor B (ETBR/EDNRB) is likely a significant node during the liver pathological change process and a promising key target for the SCDL compound schisantherin D on the hepatoprotective effect; experimental studies showed that schisantherin D alleviated the EtOH- and ET-1-induced HL-7702 cell (belongs to liver parenchymal cell lines) injury ratio, decreased the expression of ETBR, and inhibited ECMs and ET-1 secretion in LX-2 cells (one form of hepatic stellate cells). SCDLs ameliorated EtOH- and CCl-induced fibrosis formation in mice liver tissue. Liver tissue western blots of SCDL-treated mice showed downregulated α-SMA, ETBR, PLCβ, CHOP, Bax, and the apoptotic factors of cleaved-caspase 12, cleaved-caspase 9, and cleaved-caspase 3 hinted at an anti-apoptosis and hepatoprotective effect. The SCDL treatment also elevated serum glutathione (GSH) and reduced the serum-transforming growth factor-β1 (TGF-β1) level.
The findings indicated that SCDLs prevent hepatotoxicity via their anti-fibrotic, anti-oxidant, and anti-apoptosis properties. ETBR may be the key factor in promoting chemical hepatotoxicity.
化学性肝毒性，特别是酒精性肝损伤（ALI），常见于大量饮酒的年轻和中年人群。ALI 危害极大，可引起严重的疾病状态，如肝炎、肝纤维化、肝硬化或肝癌，这些疾病状态类似于动物的 CCl 诱导的肝病。在最近的研究中，肝细胞和肝星状细胞的病理变化表明内质网（ER）应激与患者肝病理学的发展之间存在显著联系。然而，详细的病理机制仍需进一步研究。五味子（Schisandra chinensis），一种用于中药（TCM）的藤本植物果实，已被用于治疗慢性或急性疾病，包括肝病。特别是五味子衍生木脂素（SCDL）已被证明可以减轻肝病理变化。
本研究旨在阐明 SCDL 介导的肝保护作用的机制。
我们首先使用基于计算的靶预测和计算模拟方法，针对肝保护作用鉴定可能与木脂素结合的靶标。进行基因微阵列分析，以鉴定可能在疾病病理过程中具有重要意义的差异表达基因。然后，我们使用小鼠肝毒性模型中的组织学分析来测试 SCDL 在体内的有效性，并使用肝细胞毒性模型来分析候选化合物介导的肝保护作用和关键靶标在体外的表达状态。
计算分析结果表明，内皮素受体 B（ETBR/EDNRB）可能是肝病理变化过程中的一个重要节点，也是 SCDL 化合物五味子丙素 D 发挥肝保护作用的有希望的关键靶标；实验研究表明，五味子丙素 D 减轻了 EtOH 和 ET-1 诱导的 HL-7702 细胞（属于肝实质细胞系）损伤比，降低了 ETBR 的表达，并抑制了 LX-2 细胞（一种肝星状细胞形式）中的 ECM 和 ET-1 分泌。SCDL 改善了 EtOH 和 CCl 诱导的小鼠肝组织纤维化形成。SCDL 处理的小鼠肝组织的 Western blot 显示 α-SMA、ETBR、PLCβ、CHOP、Bax 和凋亡因子 cleaved-caspase 12、cleaved-caspase 9 和 cleaved-caspase 3 的表达下调，提示具有抗凋亡和肝保护作用。SCDL 治疗还提高了血清谷胱甘肽（GSH）水平，降低了血清转化生长因子-β1（TGF-β1）水平。
研究结果表明，SCDL 通过其抗纤维化、抗氧化和抗凋亡特性预防肝毒性。ETBR 可能是促进化学性肝毒性的关键因素。
