八肽胆囊收缩素对肥胖大鼠血脂、胰岛素抵抗及腹内脂肪的影响

Effect of cholecystokinin-octopeptide on lipid,insulin resistance and intra-abdominal fat in diet-induced obese rats

目的观察八肽胆囊收缩素(CCK-8)对饮食诱导的肥胖大鼠肥胖、胰岛素抵抗(IR)、腹内脂肪及脂肪组织炎症因子的影响。方法将健康雄性SD大鼠分为3组:对照组(Control)、高脂组(HF)及CCK-8组。给予HF及CCK-8组大鼠高脂饲料建立肥胖及IR大鼠模型,CCK-8组给予大鼠CCK-8[200μg/(kg·d)],2次/d,腹腔注射2周。对比各组大鼠摄食量、体重、血糖、血脂及胰岛素抵抗指数(HOMA-IR)。各组大鼠进行葡萄糖耐量试验(OGTT)及胰岛素释放试验;处死大鼠后检测大鼠内脏脂肪含量,计算脂肪质量/体重比值,并检测脂肪组织炎症细胞因子、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平。结果 CCK-8组大鼠较HF组进食量明显下降;CCK-8干预后第7天开始,大鼠体重较HF组明显下降。与对照组比较,HF组大鼠三酰甘油(TG)、总胆固醇(TC)、空腹胰岛素(FINS)及HOMA-IR水平明显升高(P<0.01)。CCK-8组TG、TC及HOMA-IR水平较HF组显著下降(P<0.05)。与对照组比较,HF组大鼠腹内脂肪含量、脂肪质量/体重比值以及脂肪组织TNF-α、IL-6水平明显升高(P<0.01);与HF组比较,CCK-8组上述指标水平显著下降(P<0.05)。与对照组比较,HF组大鼠服糖后血糖水平显著升高,胰岛素分泌峰值下降,CCK-8组大鼠上述指标明显改善。结论 CCK-8可能通过抑制大鼠摄食量及脂肪组织炎症反应,影响大鼠体脂分布,最终降低大鼠血脂水平,改善IR。

【Objective】 To observe the effect of cholecystokinin-octopeptide（CCK-8） on obesity, insulin resistance（IR）, intra-abdominal fat and inflammatory cytokines in fat tissue in diet-induced obese rats.【Methods】 Healthy male SD rats were divided into 3 groups： control group, high fat diet group（HF group）and CCK-8 group. The rats in the HF group and the CCK-8 group were fed with high fat diet for 8 weeks,then CCK-8 group received CCK-8 [200 μg /（kg·d）] intraperitoneal injection twice a day for 2 weeks. Food intake, body weight, blood glucose, blood lipid and insulin resistance index（HOMA-IR） of the 3 groups were observed, and OGTT and insulin release test were conducted. Then the rats were sacrificed, intra-abdominal fat quantity, fat quality / body weight index, the levels of tumor necrosis factor-α（TNF-α） and interleukin-6（IL-6） were determined. 【Results】 The food intake in the CCK-8 group decreased significantly compared with that of the HF group, and body weight decreased too after the 7th day of CCK-8 intervention. Compared with the control group, the levels of serum triglyceride, total cholesterol, fasting insulin and HOMA-IR in the HF group increased significantly（P 〈0.01）, but these parameters significantly decreased in the CCK-8 group compared with the HF group（P 〈0.05）. The intra-abdominal fat quantity, fat quality / body weight index, the levels of TNF-α and IL-6 in fat tissue in the HF group were higher than those in the control group（P 〈0.01）, and these parameters were decreased in the CCK-8 group compared with the HF group（P 〈0.05）. After oral glucose load, serum glucose level significantly increased and insulin secretion peak value decreased in the HF group compared with the control group, and these parameters were improved in the CCK-8 group.【Conclusion】CCK-8 may inhibit the food intake and inflammatory reaction of adipose tissue, affect the distribution of body fat in rats, utlimately reduce the blood lipid level and alleviate insulin resistance.