摘要： 为了探究大豆异黄酮通过瘦素减重的作用机制,建立食源性肥胖大鼠模型,后进行低、中、高剂量(50,150,450 mg/kg)大豆异黄酮干预,并每周定期称量记录体重,采用苏丹Ⅲ染色、SABC免疫组织化学法和核酸原位杂交法,观察大豆异黄酮对肥胖大鼠体重、腹部脂肪细胞形态和下丘脑弓状核及垂体α-MSH、POMC mRNA、Ob-Rb mRNA表达的影响。结果显示,标准对照大鼠α-MSH在弓状核、垂体神经部和中间部均大量表达,POMC mRNA在弓状核和垂体仅少量表达,Ob-Rb mRNA仅在弓状核表达,同时肥胖大鼠3种因子表达均显著降低;大豆异黄酮干预后肥胖大鼠体重降低,腹部脂肪细胞面积缩小且形态分布明显改善,同时α-MSH、POMC mRNA、Ob-Rb mRNA表达增多。表明大豆异黄酮可能通过减少脂储、增加Ob-Rb表达从而促进具有抑食作用的POMC及其裂解物α-MSH产生,从而改善大鼠瘦素抵抗状态,发挥减重作用。

关键词: 大豆异黄酮, 肥胖大鼠, 免疫组织化学SABC, 原位杂交, α-MSH, POMC, Ob-Rb

Abstract: To study the weight loss mechanism of soy isoflavone dependent on leptin.In the present study,the food-induced obese rats model was established treated with low,medium and high dose soy isoflavone,to investigate the effects of soy isoflavone on body mass,morphology of fat cell inside the abdomen,expression of α-MSH、POMC mRNA、Ob-Rb mRNA in the hypothalamic arcuate nucleus and pituitary,by weighting every week,Sudan Ⅲ staining,immunohistochemical and in situ hybridization analysis.The results showed α-MSH abundantly expressed in the arcuate nucleus,neurohypophysis and pars intermedia,POMC mRNA rarely expressed in the arcuate nucleus and pituitary,and Ob-Rb mRNA only expressed in the arcuate nucleus,simultaneously the three factors were significantly less present in fat rats.After treated with soybean isoflavones,the body weight of obese rats decreased,the area of abdominal fat cells reduced and distribution improved significantly,also the expression of α-MSH,POMC mRNA,Ob-Rb mRNA increased,which could be positively correlated with the dose.Results suggested that soy isoflavone might reduce fat storage and stimulated Ob-Rb expression,then promoted production of POMC and α-MSH,thus improve the state of leptin resistance in rats,and cause weight loss.

Key words: Soy isoflavone, Obese rat, Immunohistochemistry, Hybridization situ, α-MSH, POMC, Ob-Rb

中图分类号: 

• Q78

• S565.03