摘要
目的探讨内质网应激在非酒精性脂肪性肝纤维化形成中的作用及饮食控制对脂肪性肝纤维化恢复的影响。方法蛋氨酸-胆碱缺乏饮食(MCDD)喂养10周诱导非酒精性脂肪性肝纤维化大鼠模型,恢复组于第9周开始将MCDD转变为蛋氨酸-胆碱对照饮食(MCCD)喂养2周。纤维化和炎症程度采用组织病理染色方法检测,纤维化和炎症相关因子采用Western blot和实时定量聚合酶链反应(RT—PCR)方法检测,内质网应激标记物半胱氨酸天冬氨酸蛋白酶(caspase)12、7和葡萄糖调节蛋白78(GRP78)采用免疫组织化学、Western blot和RT—PCR方法检测。计量资料采用统计分析软件SPSS13.0中的ANOVA程序进行单因素方差分析或q检验,并用LSD进行两两比较。结果饮食由MCDD转变为MCCD后,组织病理学结果显示肝细胞脂肪沉积及炎症反应明显减轻,伴随着活化的肝星状细胞和枯否细胞减少,肝纤维化程度明显减轻。模型组大鼠肝细胞凋亡数为每5个高倍视野(68.2±15.9)个,明显高于正常组(40.3±8.3)个,P〈0.05;肝细胞增殖/凋亡比值(0.10±0.03)明显低于正常组(0.19±0.03),P〈0.01。恢复组大鼠肝细胞凋亡数为每5个高倍视野(48.0±6.5)个,明显低于模型组(68.2±15.9)个,P〈0.05;增殖数为每5个高倍视野(17.2±4.4)个,明显高于模型组(7.5±3.0)个,P〈0.01;肝细胞增殖/凋亡比值(0.41±0.09)也明显高于模型组(0.10±0.03),P〈0.01。模型组大鼠肝组织GRP78、caspase12、caspase7和cleaved caspase 7蛋白质和mRNA表达均明显高于正常组(P〈0.05或P〈0.01),恢复组均明显低于模型组(P〈0.05或P〈0.01)。结论大鼠饮食由MCDD转变为MCCD后,肝脏的炎症和纤维化程度迅速逆转,提示饮食摄取对于控制肝脏脂肪沉积和病理改变至关重要,且内质网应激参与了这一过程,阻断内质网应激尤其是caspase12通路也许有助于非酒精性脂肪性肝纤维化的临床治疗。
Objective To study role of endoplasmic reticulum stress in the development of fatty liver fibrosis induced by methionine-choline-deficient diet in rats. Methods Non-alcoholic steatohepatitis was induced by 10 weeks- methionine-choline-deficient diet (MCDD), Markers of endoplasmic reticnlum stress were determined by immunoblotting and real-time PCR. Results The number of apoptotie bepatocytes, The expression levels of endoplasmic reticulum stress markers were increased significantly in MCDD group compared to control group (P 〈 0.05 or P 〈 0.01), while ratio of hepatocyte proliferation/apoptosis was decreased in MCDD group (P 〈 0.01). The number of bepatocytes apoptosis, and the expression levels of endoplasmic reticulum stress markers were decreased significantly 2 weeks after the feeding with normal diet in MCDD group (P 〈0.05 or P 〈 0.01), Conclusions MCDD induces endoplasmic reticulum stress and fibrosis in rats.
出处
《中华肝脏病杂志》
CAS
CSCD
北大核心
2010年第2期124-130,共7页
Chinese Journal of Hepatology
基金
日本医学振兴会研究基金(18659214)
关键词
肝硬化
非酒精性
内质网
枯否细胞
肝星状细胞
细胞凋亡
Liver cirrhosis, nonalcoholic
Endoplasmic reticulum
Kupffer cells
Hepatic stellate cells
Apoptosis