蓝莓对非酒精性脂肪性肝病大鼠Bcl-2、Bax表达的影响

Effect of blueberry on expression of Bcl-2 and Bax in non-alcoholic fatty liver disease in mice

目的:研究蓝莓对非酒精性脂肪性肝病(nonalcoholic fatty liver disease,NAFLD)大鼠的保护作用及相关机制.方法:40只健康大鼠随机分为4组:正常组、蓝莓组、姜黄素组、模型组.正常组饲喂正常饲料,其余各组饲喂高脂饲料.蓝莓组每日灌胃蓝莓原浆[15 m L/(kg·d)];姜黄素组每日灌胃姜黄素溶液[200 mg/(kg·d)];其余组大鼠灌胃等体积生理盐水,12 wk后处死.HE染色、油红O染色观察各组肝细胞损伤及脂肪沉积情况;全自动生化分析仪检测血清谷丙转氨酶(alanine transaminase,ALT),谷草转氨酶(aspartate transaminase,A S T),甘油三脂(t r i g l y e r i d e,T G),胆固醇(total cholesterol,TC)含量;酶联免疫吸附法检测肝组织中超氧化物歧化酶(superoxide dismutase,SOD)活性及谷胱甘肽(glutathione,GSH)、丙二醛(malondialdehyde,MDA)、甘油三酯(triglyeride,TG)含量;免疫组织化学、Western blot和逆转录-聚合酶链反应检测大鼠肝组织中B淋巴细胞瘤-2(B-celllymphoma-2,Bcl-2)、Bcl-2相关x蛋白(bclassociated x protein,Bax)的表达.结果:与模型组大鼠相比,蓝莓组、姜黄素组HE染色、油红O染色肝组织中脂肪沉积明显减少,血清AST、ALT、TG、TC含量升高幅度较小(P<0.01),肝组织中TG、MDA含量升高幅度也较小(P<0.01),而SOD活性、GSH含量明显增高(P<0.01).与模型组大鼠相比,蓝莓组、姜黄素组Bcl-2 mR NA和蛋白质的表达明显增加(P<0.01),Bax m RNA和蛋白质的表达明显降低(P<0.01),Bcl-2/Bax比值明显增加(P<0.01).结论:蓝莓对NAFLD有较好的预防作用,其机制可能是上调肝脏Bcl-2表达,下调Bax表达,纠正两者平衡失调,提高机体抗氧化能力从而抑制肝细胞凋亡有关.

AIM： To investigate the effect of blueberry on non-alcoholic fatty liver disease in mice and the underlying mechanism.METHODS： Forty healthy SD mice were randomly divided into a normal control group, a blueberry group, a curcumin group and a model group. The normal control group was given a normal diet, and the other groups were all given a high fat diet. The blueberry group was intragastrically given blueberry juice [15 m L/（kg·d）], the curcumin group was given curcumin solution [200 mg/（kg·d）], and the other groups were given physiological saline daily. At the end of 12 wk, all mice were sacrificed. Liver cell injury and fat deposition were assessed by HE staining and oil red O staining, respectively. The levels of alanine transaminase（ALT）, aspartate transaminase（AST）, triglyeride（TG） and total cholesterol（TC） in serum were detected with an automatic biochemical analyzer. Hepatic TG, T C, malondialdehyde（MDA）, glutathione（GSH） and superoxide dismutase（SOD） were quantified by ELISA. The expression of Bcl-2 and Bax in liver tissue was detected by immunohistochemistry, Western blot and RT-PCR. RESULTS： Compared to the model group, the blueberry and curcumin groups showed significantly decreased lipid accumulation, serum levels of ALT, AST, TG and TC（P〈0.01）,and hepatic levels of TG and MDA（P〈0.01）,and increased GSH contents and SOD activity（P〈0.01）. Compared to the model group, the blueberry and curcumin groups also showed significantly in creased Bcl- 2 mRNA and protein expression（P〈0.01）, significantly decreased Bax m RNA and protein expression（P〈0.01）, and significantly increased Bcl-2/Bax ratio（P〈0.01）. CONCLUSION： Blueberry has a protective effect on non-alcoholic fatty liver disease in mice, and the mechanism may be associated with up-regulating the Bcl-2 expression, downregulating Bax expression, correcting balance disorders, and enhancing the body＇s antioxidant ability to inhibit liver cell apoptosis.