RNAi介导的SOCS3基因沉默对高脂肥胖大鼠瘦素抵抗的影响

摘要

To study the effects of RNAi - mediated SOCS3 gene silence on leptin resistance in obese rats fed with high - fat diet. Methods Sixty five - week - old healthy male SD rats were divided into three groups randomly. In experiment group, the lentiviral vector expressing a short - hairpin RNA targeting SOCS3 gene ( LV - shSOCS3) were stereotaxically injected into the hypothala-mus of rats which then fed with high - fat diet. In the negative group, the lentiviral vector expressing a short - hairpin RNA targeting an unrelated sequence (LV - negtive) were stereotaxically injected into the hypothalamus of rats which then fed with high -fat diet; In the control group, the normal sodium were stereotaxically injected into the hypothalamus of rats which then fed with high - fat diet. At the end of 8 weeks, serum lipid levels including total cholesterol, triglyceride, high density lipoprotein cholesterol and low density lipoprotein cholesterol were determined. Serum leptinlevels were measured by radioimmunoassay. Real - time PCR were used to evaluate the level of SOCS3mRNA and OB - Rb mRNA in the hypothalamus. Results The body weight of rats was decreased significantly in experiment group (P＜0.05).The concentrations of serum leptin,triglyceride,total cholesterol and low density lipoprotein cholesterol in experiment group were decreased obviously compared with control group and negative group (P＜0. 05). The expression of SOCS3 mRNA in experiment group were decreased markedly compared with control group and negative group (P＜0. 05 ) . The expression of OB - Rb mRNA in experiment group were increased markedly compared with control group and negative group (P＜0.05). There were no significant differences in control group and negative group ( P＞0.05 ). Conclusion The down - regulated expression of SOCS3 gene reduces leptin resistance in obese rats fed high - fat diet.%目的 研究RNA干扰(RNAi)介导的细胞因子信号转导抑制因子3(SOCS3)基因沉默对高脂肥胖大鼠瘦素抵抗的影响.方法 选用5周的SD大鼠60只,随机分为3组,实验组:下丘脑注射SOCS3基因RNA干扰慢病毒(LV - shSOCS3),高脂饲料喂养；阴性组:下丘脑注射阴性序列慢病毒( LV - negtive),高脂饲料喂养；对照组:下丘脑注射生理盐水,高脂饲料喂养.饲养8周末,检测血总胆固醇、三酰甘油、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇,放射免疫法检测血清瘦素,利用荧光实时定量PCR(real - time PCR)技术检测各组下丘脑内SOCS3和瘦素受体(OB - Rb)的mRNA表达水平.结果 实验组体重、瘦素、三酰甘油、总胆固醇、低密度脂蛋白胆固醇低于阴性组和对照组(P＜0.05).实验组下丘脑的SOCS3mRNA水平低于阴性组和对照组(P＜0.05).实验组下丘脑的OB - RbmRNA水平高于阴性组和对照组(P＜0.05).而阴性组和对照组比较无差异(P＞0.05).结论 下调SOCS3基因可以减轻高脂肥胖大鼠瘦素抵抗,对肥胖症可能有预防和治疗作用.