雌激素代谢产物介导雌激素抗肝纤维化作用

Fibrosuppressive effects of β-Est mediated via its metabolites in CCl_4 rat

目的 探讨 β Est抑制大鼠肝纤维化形成的可能作用途径。 方法 在动物实验中采用皮下注射CCl4 制作大鼠肝纤维化模型 ,观察 2 0 μg/kg/dβ Est对完整或去势雌性大鼠肝纤维化形成的影响。 6周后收集肝组织和血清标本 ,以标准酶法、ELISA、RIA分别测定血清肝功能、ECM及E2 水平 ;VG染色胶原染色及α SMA免疫组化观察肝组织病理学改变 ,结合图像分析计算胶原面积。在细胞学实验中采用原位酶灌注法和密度梯度离心法分离HSC。初次传代后的HSC被随机分成 10组 ,分别加入不同浓度 β Est、2 0HE、2Me0E ,加药后 72h ,采用MTT、ELISA及免疫组化法分别检测HSC增殖、培养液中HA、CIV含量及细胞中α SMA、ER表达。结果 β Est能抑制雌性大鼠纤维化形成 ,改善肝功能 ,降低ECM分泌、肝组织纤维化程度及α SMA表达 ,肝组织纤维化程度与血清E2水平呈负相关 ,相关系数为 -0 57;10 - 9M～ 10 - 7M浓度的 β Est、2 0HE、2Me0E能抑制活化HSC增殖、分泌ECM ,呈剂量依赖关系 ,而10 - 7M浓度β Est、2 0HE、2Me0E均能抑制活化HSC表达α SMA ,强度依次为 2Me0E >2 0HE >β Est。

Objective To investigate the pathway via which β-Est exerts fibrosuppressive effects in rats. Methods In vivo studies,liver fibrosis was induced by CCl 4.The fibrosis -suppressive effect of β-Est(20μg/kg/d)was evaluated in intact or gonadectom ized female rat model.6 weeks after the treatment,all the rats were sacrificed a nd specimens of serum or liver tissue were collected for the studies.The serum l iver enzymes,fibrosis indicators and E 2 levels were determined by standard enz ymatic methods,ELISA and RIA respectively.The degrees of fibrosis and areas of H SCs positive for α-SMA in the liver were determined by VG stain and immunohist ochemistry.In vitro studies,HSCs were isolated by a combination of pronase-coll agenase perfusion and density gradent centrifugation.The passaged HSCs were rand omly divided into 10 groups,and different concentrations of β-Est,2OHE of 2MeO E were seperately added to the cell groups.After incubation for 72 hours,the deg r ee of cell proliferation,ECM secretion,α-SMA or ER expression were determined by MTT assay,ELISA and immunohistochemistry respectively.Results β-Est treatment could decrease serum liver enzymes,reduce collagen conte nt and lower areas of HSCs positive for α-SMA in the liver.And there was a neg ative correlation between the collagen percentage area of liver tissue and serum estradiol level,calculated correlation coefficient was-0.57.β-Est and its met a bolites concentration-dependently(10 -9 M～10 -7 M) inhibited cell prol iferation and collagen synthesis.While at the concentration of 10 -7 M,they could inhibit α-SMA expression.The order of potency is 2MeOE>2OHE>β-Est. Conclusion β-Est can suppress hepatic fibrosis via its biologically active metabolites.