大豆异黄酮对胰岛素抵抗大鼠低度炎症因子水平的影响

Effects of soy isoflavone on levels of low-grade inflammatory peptides in rats with insulin resistance

目的探讨大豆异黄酮(SIF)对膳食诱导的胰岛素抵抗大鼠低度炎症介质水平的影响,以初步阐明大豆异黄酮改善肥胖性胰岛素抵抗状态的可能机制。方法选用高脂饲料诱导的IR雄性SD大鼠,随机分为模型对照组和3个SIF组(50、150及450mg/kg·b.w.)。各组给予相应受试物1月,禁食过夜后股动脉采血处死各大鼠,分离肾周及睾周白色脂肪。酶法检测各组动物空腹血糖,放免法检测空腹血胰岛素IL-6及TNF-α,酶免法检测血清C-反应蛋白、抵抗素与脂联素含量。结果与模型对照组比较:150mg/kg·b.w.与450mg/kg·b.w.组的内脏脂肪/体质量比、血清胰岛素、胰岛素抵抗指数TNF-α及抵抗素含量明显降低;450mg/kg·b.w.组能明显降低血清IL-6及提高脂联素的含量;3个SIF组的C-反应蛋白水平与模型组比较无明显差异。结论SIF具有提高胰岛素抵抗大鼠胰岛素敏感性的作用,可能是通过减少大鼠体内脂肪沉积、调整脂肪源低度炎症介质的分泌而实现的。

Objective To explore the effects of soy isoflavone （SIF） on low-grade inflammation in rats with high-fat diet-induced insulin resistance （IR） and explore the mechanisms of SIF in improving insulin sensitivity. Methods The rats with high-fat diet-induced IR were randomly divided into one model control group and 3 SIF groups gavaged with SIF water solutions at the doses of 50, 150, and 450 mg/kg, respectively. One month after the treatment, fasting blood glucose （FBG）, fasting insulin （FINS）, interleukin-6 （IL-6）, tumor necrosis factor-α （TNF-α, C-reactive protein （CRP）, resistin and adiponectin in the serum were detected by enzymatic method, radioimmunoassay, or enzyme-linked immunosorbent assay. Results In the 150 and 450 mg/kg SIF groups, fasting body-weights, visceral adipose tissue deposition, FINS, resistin, TNF-α in serum, and IR index were lowered in comparison with the model control group, and in 450 mg/kg SIF group, serum IL-6 level was obviously lowered, and adiponectin increased. No differences were found in serum C-reactive protein levels between the 3 SIF groups. Conclusion Soy isoflavone may ameliorate insulin sensitivity by decreasing visceral adipose deposition and adjusting low-grade inflammatory molecules derived from white adipose tissue.