摘要
目的探讨腺苷蛋氨酸(SAM)防治大鼠酒精性肝病的作用机制。方法健康雄性wistar大鼠30只,随机分为对照组、模型组和SAM干预组。模型组大鼠采用逐渐增加浓度(30%-60%)和剂量(5-9g·kg-1·d-1)的方法酒精灌胃16周,干预组增加SAM(100mg/kg)灌胃,其它同模型组。16周末随机处死动物,检测血清总同型半胱氨酸(tHcy)的浓度和肝组织胱硫醚β合成酶(CBS)的活性;分别采用免疫组化方法和RT-PCR法检测肝组织中GRP-78、calpain 2及其caspase-12的表达;采用TUNEL染色法检测肝细胞凋亡。结果模型组大鼠16周末出现肝细胞弥漫小泡性脂肪变性,窦周纤维化,汇管区纤维组织增生并有纤维间隔形成。SAM组病理改变较模型组明显减轻。SAM组血清tHcy的浓度(7.00±0.79)较模型组(9.85±0.12)明显降低,而CBS的活性(511.60±57.44)较模型组(390.45±31.17)升高,F值分别为147.28和41.14,P值均<0.01;免疫组化和RT-PCR结果显示SAM组GRP-78、Calpain 2、caspase-12的表达较模型组减弱;SAM组的肝细胞凋亡指数(31.24±2.65)较模型组(65.71±9.78)降低,F值为301.79,P<0.01。结论在大鼠酒精性肝病中,腺苷蛋氨酸通过提高胱硫醚β合成酶活性,改善内质网应激,减少肝细胞凋亡,减轻肝脏损伤。
Objective To investigate the mechanism of S-adenosyl methionine （SAM） inhibiting endoplasmic retieulum （ER） stress and preventing hepatocyte apoptosis in rat alcoholic liver disease. Methods Thirty male Wistar rats were randomly divided into 3 groups： control group, model group and SAM- treated group （SAM group）. The model group was treated with intragastric alcohol of gradually increasing concentration and dose （30%- 60%, 5-9g/kg/d） for 16 weeks. The SAM group was treated with alcohol plus SAM（100mg/kg）. After the animals were sacrificed randomly at week 16, the serum level of total homocysteine （tHcy） and the activity of cystathionine beta-synthase （CBS） in liver tissue were examined . The expressions of GRP-78, calpain 2,caspase-12 and procaspase-12 were analyzed by reverse transcription-polymerase chain reaction（RT-PCR） and immunohistochemistry respectively. Hepatocyte apoptosis was determined by TdT-mediated dUTP nick end labeling（TUNEL）. Results At the 16th week, diffuse microvesicular adipose degeneration, fibrosis in liver sinus and fibrosis septa in portal area were observed in hepatic tissue of the model group. SAM suppressed the development of alcohol-induced liver injury . The serum level of tHcy in the SAM group was significantly lower than that in the model group （P〈0.01）, and the activity of CBS was increased in the SAM group compared with that in the model group （P〈0. 01）. The expression of GRP-78, Calpain 2 and caspase 12 decreased in the SAM group. In addition, the hepatocyte apoptosis index （AI） in the SAM group was lower than in the model group. Conclusion SAM can prevent hepatocyte apoptosis and improve liver injury by increasing the activity of CBS and inhibiting endoplasmic reticulum stress in rats with alcoholic liver disease.
出处
《中国组织化学与细胞化学杂志》
CAS
CSCD
2012年第3期224-229,共6页
Chinese Journal of Histochemistry and Cytochemistry
基金
河北省医学科学研究重点课题(20100101)
