表没食子儿茶素没食子酸酯对高脂饮食大鼠脂肪组织TNF-α表达的影响及意义  

Effects of Epigallocatechin-3-Gallatein on the Expression of TNF-α in Adipose Tissue of Obesity Rats

作　　者：暴素青 曹艳丽[1,2] 张乐[1,2] 张媛媛[1,2] 单忠艳[1,2] 滕卫平[1,2] 

机构地区：[1]中国医科大学附属第一医院内分泌科 [2]中国医科大学内分泌疾病研究所,辽宁省内分泌疾病重点实验室,沈阳110001

出　　处：《中国组织化学与细胞化学杂志》2013年第6期475-479,共5页Chinese Journal of Histochemistry and Cytochemistry

基　　金：国家自然科学基金资助(81000327);中华医学会内分泌分会资助(12030470347)

摘　　要：目的探讨表没食子儿茶素没食子酸酯(EGCG)对高脂饮食大鼠脂肪组织中肿瘤坏死因子-α(TNF-α)表达的影响及其与胰岛素敏感性的相关性。方法将30只SPF级雄性SD大鼠随机分为正常饮食组(ND组,n=10)和高脂饮食组(HFD组,n=20)。喂养16w,当两组大鼠体质量出现显著差异后(P<0.05),将HFD组按随机区组原则分为单纯高脂组(HFD组,n=10)和EGCG干预组(HFD+0.32%EGCG,EGCG组,n=10)。干预16w。留取血清及附睾周脂肪组织。检测每组大鼠空腹血糖(FBG)、胰岛素水平(FINS)及游离脂肪酸(FFAs),并计算胰岛素抵抗指数(HOMA-IR);应用Real-time PCR及Western blot方法检测附睾周脂肪组织中TNF-α表达水平。结果 (1)与HFD组相比,EGCG组FINS水平显著下降[分别为(13.83±0.79)mIU/l vs.(31.71±3.61)mIU/l,P<0.05];HOMA-IR值下降[分别为(3.36±0.31)vs.(7.59±0.99),P<0.05];FFAs值亦明显下降[分别为(0.38±0.08)mmol/l vs.(0.81±0.11)mmol/l,P<0.05];三组大鼠FBG水平无明显统计学差异(P>0.05)。(2)与ND组相比,HFD组脂肪组织中TNF-αmRNA水平显著升高[分别为(0.0033±0.00070)vs.(0.0010±0.00008),P<0.01];而EGCG组较HFD组则明显下降[分别为(0.0018±0.00037)vs.(0.0033±0.00070),P<0.05];同时,EGCG组TNF-α蛋白表达量低于HFD组[分别为(0.42±0.09)vs.(0.67±0.09),P<0.05];(3)EGCG组与ND组无明显差异(P>0.05)。结论 EGCG改善高脂饮食大鼠胰岛素敏感性可能与减轻脂肪组织TNF-α介导的炎症状态相关。Objective To investigate the effects of epigallocatechin-3-gallatein on the expression of tumor necrosis factor-α （TNF-α） in adipose tissue of rats with high-fat diet and its relationship with insulin resistance. Methods 30 male SD rats were divided into two groups： normal diet （ND, n=10） and high-fat diet （HFD, n=20）. When there was a significant difference in body weight between the two groups （P〈 0.05）, the HFD group was divided into two subunits, the HFD group （HFD, n= 10, 16wks） and the EGCG group （HFD＋EGCG, 3.2g/kg diet, n=10, 16wks）. The levels of plasma glucose, fasting plasma insulin （FINS）and free fatty acids （FFAs） were assessed. Insulin resistance was calculated by the homeostasis model assessment-insulin resistance index （HOMA-IR index）. The level of TNF-α was examined in epididymal white fat by Western-blotting and RT-PCR. Results （1）Compared with the HFD group, the EGCG group showed significant decreases in FINS [（13.83±0.79） mIU/1 vs. （31.71±3.61） mlU/l, P 〈0.05], HOMA-IR[（3.36±0.31） vs. （7.59±0.99）, P〈0.05], andFFAs [（0.38±0.08） mmol/lvs. （0.81±0.11） mmol/1, P〈0.05]. （2） The protein level of inflammation-related molecules TNF-α in the EGCG group was significantly lower than that of the HFD group [（0.42±0.09）vs. （0. 67±0.09）, P〈0. 05]; so was the level of mRNA expression of TNF-α[（0. 0018±0. 00037）vs. （0.0033±0.00070）, P〈0. 05]. （3） There were no significant diffferences between the ND group and the EGCG group （P〉0.05）. Conclusion EGCG enhances insulin signaling, Which may be correlated with its downregulation of TNF-α expression in adipose tissue.

关 键 词：EGCG 肿瘤坏死因子-α 脂肪组织 炎症 胰岛素敏感性 

分 类 号：R589.2[医药卫生—内分泌]