中文摘要：

目的：观察溪黄草总二萜的保肝作用。方法：制备乙醇损伤L-02细胞模型,考察总二萜对受损细胞ALT、AST泄漏量的影响。复制两种急性肝损伤动物模型,分离血清检测转氨酶活性,取肝组织进行病理学观察。提取肝脏线粒体检测MMP、MPTP开放程度、Mn-SOD活力、8-OHd G水平、呼吸链复合物Ⅰ、复合物Ⅲ活性。肝匀浆测定MDA水平和GSH、GSH-Px活力。RT-PCR检测大鼠肝组织中Nrf2、Bach1、HO-1 mRNA表达水平;Western Blot检测大鼠肝组织HO-1总蛋白的表达水平。结果：细胞实验显示,溪黄草总二萜5.00、10.00、20.00μg/ml给药组有降低受损L-02细胞转氨酶泄漏的趋势。动物实验显示,溪黄草总二萜25.0、50.0、100.0 mg/kg治疗组动物血清转氨酶水平均明显下降,肝细胞水肿减轻,病理分级下降。溪黄草总二萜25.0、100.0 mg/kg治疗组动物肝脏线粒体Mn-SOD、ComplexⅠ、ComplexⅢ活性上升;50.0 mg/kg治疗组MPTP开放被抑制、8-OHd G水平下降。溪黄草总二萜25.0、50.0、100.0 mg/kg治疗组动物肝匀浆中MDA水平下降,GSH、GSH-Px活力升高。溪黄草总二萜50.0、100.0 mg/kg治疗组大鼠肝组织中HO-1 mRNA、总蛋白表达水平上升。结论：溪黄草总二萜在细体内外实验中显示均具有明确的保肝作用,其保肝作用与保护肝脏线粒体、调控肝脏内源性抗氧化酶系统有关。

英文摘要：

Objective： to investigate the hepatoprotective effect of total diterpenoids extracted from Isodon serra （Maxim.） Hara. Methods： We prepared the ethanol-damaged L-02 cells and measured the ALT and AST levels in culture media. Two types of acute liver injuries were re-es- tablished in animals. T activities were measured in serum, HE stain and pathological observation were performed in liver tissue The liver mitochondria were separated from fresh liver tissue and multiple indexes were examined. MDA, GSH, GSH-Px were detected in liver homogenate. Along with the expression of HO-1 total protein, the mRNA expression of Nrf2, Bachl and HO-lwere checked in rats＇liver. Results ： There was a trend on cutting down the leakage of ALT and AST from ethanol-damaged L-02 cells treated with 5.00, 10.00, 20.00 μg/ml total diterpenoids. Compared with model group, ALT and AST levels in total diterpenoids 25.0, 50.0, 100.0 mg/kg group were remarkably lowered, followed by the relief of liver cells edema and improvement of pathology classification. The results of examination on hepatic mitochondria showed that Mn-SOD, complex Ⅰ, complex Ⅲ activities significantly increased in total diterpenoids 25.0, 100.0 mg/kg group ; the opening of MPTP was inhibited and 8-OHdG levels dropped in total diterpenoids 50.0 mg/kg group. With the recovery of GSH and GSH-Px activities, the MDA levels were significantly lower in total diterpenoids 25.0, 50.0, 100.0 mg/kg group. Both mRNA and total protein expressions were considerably up-regulated in total diterpenoids 50.0, 100.0 mg/kg rats. Conclusion： Total diterpenoids extracts from Isodon serra （Maxim.） Hara had a considerable hepatoprotective effect both in vivo and in vitro. The animal experiment indicates that its effect is related to hepatic mitochondria protection and endogenous antioxidative system adjustment.