四种中药单体的抗肝纤维化作用及其机制

目的 比较丹参素、黄芩甙、黄芪、三七总皂甙4种中药单体抗肝纤维化的疗效并探讨其作用机制.方法 以秋水仙碱为对照,将4种中药用于大鼠肝纤维化模型和大鼠肝星状细胞(HSC).观察肝组织形态变化;检测血清透明质酸、Ⅳ型胶原含量;检测肝组织羟脯氨酸、丙二醛(MDA)含量,超氧化物歧化酶(SOD)活性,基质金属蛋白酶-1(MMP-1)、基质金属蛋白酶组织抑制因子-1(TIMP-1)、转化生长因子(TGF)β1的表达;观察HSC活化增殖周期、细胞凋亡及Ⅰ、Ⅲ型胶原蛋白的表达.结果 与模型组比较,中药处理组的肝组织形态显著改善,血清透明质酸、Ⅳ型胶原含量明显减少,肝组织MDA、羟脯氨酸含量及TIMP-1、TGF β1表达亦明显减少、SOD活性显著升高,丹参素组作用最强,黄芩甙组、黄芪组次之,各组比较,差异有统计学意义(P＜0.01或P＜0.05).四种中药都能抑制HSC活化增殖、促进细胞凋亡、抑制HSC的Ⅰ、Ⅲ型胶原蛋白表达,丹参素、黄芩甙、黄芪作用较强.结论 四种中药均能减缓实验性肝纤维化的发生.丹参素作用最强,黄芩甙和黄芪强于三七总皂甙.机制可能是这些中药能通过下调TGF β1抑制HSC活化增殖、促进细胞凋亡而抑制HSC的Ⅰ、Ⅲ型胶原蛋白表达;降低肝组织MDA含量,增加SOD活性;下调TIMP-1/MMP-1比值从而促进细胞外基质降解,减少其沉积.

Inhibiting effects of denshensu,baicalin,astragalus and Panax notoginseng saponins on hepatic fibrosis and their possible mechanisms

OBJECTIVE: To study the anti-fibrotic effects of danshensu, baicalin, astragalus and Panax notoginseng saponins (PNS) and their possible mechanisms. METHODS: The four Chinese herb products mentioned above were given intraperitoneally to experimental rats with hepatic fibrosis. Colchicine was administered to a control group. Comparisons were made in four aspects: (1) Degrees of liver fibrosis; (2) Serum levels of hyaluronic acid (HA) and type IV collagen (CIV), using radioimmunoassay; (3) Densities of malondialdehyde (MDA), superoxide dismutase (SOD) and hydroxyproline (Hyp), using chromatometry, to detect the expression of tissue inhibitors of matrix metalloproteinase-1 (TIMP-1), matrix metalloproteinase-1(MMP-1) and transforming growth factor beta 1 (TGF beta 1) in liver tissues, using immunhistochemical techniques; and (4) For hepatic stellate cells (HSCs): proliferation using MMT calorimetric assay, the cell cycles using flow cytometry, apoptosis using AO/EB fluorescence staining and type I and type III collagens using immunocytochemical stainings. RESULTS: (1) Compared with the model group, the serum levels of HA and CIV decreased significantly in all four drug-treated groups, especially in the danshensu-treated group. Astragalus and baicalin had better effects over PNS (P<0.05 or 0.01). (2) In contrast to the model group, all four drugs dramatically reduced the amount of Hyp and MDA, increased SOD activity and reduced the degrees of liver fibrosis and the expressions of TIMP-1 and TGFbeta1 in liver tissues (P<0.05 or 0.01). Danshensu had the best effect, astragalus and baicalin had similar effects which were stronger than PNS. (3) All four drugs inhibited HSCs proliferation, induced HSCs apoptosis and decreased type I, III collagen synthesis of HSC. CONCLUSIONS: The four drugs could minimize the hepatic fibrosis of rats in different degrees. Danshensu had the best effect, astragalus and baicalin had similar effects. The possible mechanisms of these effects might be related to inhibiting actions on activation and proliferation, promoting apoptosis and lowering the expression of type I and type III collagen of HSCs by down-regulating the expression of TGFbeta1; the decrease in the amount of MDA and the increase of SOD activity; and the reduction of extracellular matrix by down-regulation of TIMP-1/MMP-1.