抗氧化剂对大鼠肝星形细胞增殖和凋亡影响的实验研究

目的　了解膳食维生素E和硒对大鼠肝纤维化恢复期肝星形细胞 (HSC)增殖和凋亡的影响。方法　采用腹腔内注射 5 0 %CCl4 制备大鼠肝纤维化模型 ,在饲料中添加适量维生素E(2 5 0mg kg饲料 )和Se(0 . 2mg kg饲料 )进行营养干预 ,在最后一次注射后 3、7、14、2 8天 (恢复期 )各处死 3只大鼠取其肝组织 ,用HE和Siriusred染色结合图象分析检测肝纤维化指标 ,用α SMA免疫组化方法检测激活的HSC细胞 ,用原位凋亡 (TUNEL)技术和α SMA免疫组化双标染色检测HSC凋亡。结果　在恢复期各时间点 ,病理对照组和抗氧化干预组激活的HSC数量呈逐步下降趋势 ,同时 ,从恢复期第 7d开始 ,HSC凋亡细胞数以及肝组织内的胶原量亦同步下降 ;在同一时间点 ,干预组激活的HSC数量低于病理对照组 ,而HSC凋亡数和凋亡率均高于病理对照组。结论　饲料中添加适量维生素E和硒能减轻肝纤维化的程度 ,并可能使恢复期HSC凋亡增加 ,激活HSC数量减少。

Effect of antioxidant on hepatic stellate cell proliferation and apoptosis during recovery from liver fibrosis

OBJECTIVE: Effects of dietary supplementation of vitamin E and selenium on proliferation and apoptosis of activated hepatic stellate cell(HSC) were investigated in the rat model of liver fibrosis induced by intraperitoneal injection with CCl4. METHODS: Activated HSC was determined by alpha-smooth muscle actin immunohistochemistry staining and apoptotic HSC determined by dual staining both of the terminal deoxynucleotidyl transferase UTP nick end labeling(TUNEL) and of alpha-smooth muscle actin immunohistochemistry. RESULT: During fibrosis recovery, the number of activated HSCs both in pathological group and in intervention group went down gradually,meanwhile, both the number of apoptotic HSCs and the collagen liver also descend little by little. These data confirmed that HSCs had the core effect on liver fibrogenesis and apoptosis may be a major factor regulating HSCs numbers during the injury-fibrosis-recovery sequence. At each time point, the number of activated HSCs in pathological group is more than intervention group, while apoptotic HSCs are less, which suggested dietary supplement with antioxidative nutrients had effect on HSC apoptosis but more studies are necessary to make the mechanism clearer. CONCLUSION: Dietary supplement with proper vitamin E and selenium can effectively lighten the hepatic fibrosis and promote the recovery of hepatocyte and the degradation of the existing collagens, ie, it is beneficial to the recovery of hepatic fibrosis.