实验性牙周炎对肥胖大鼠血清C反应蛋白及胰岛素抵抗的影响

目的:探讨实验性牙周炎对肥胖大鼠血清C反应蛋白(CRP)及胰岛素抵抗指数(HOMA-IR)随时间的变化.方法:4 周龄SD大鼠(n=35)高脂饲料喂养16 周建立肥胖模型.按肥胖指标筛除5 只,其余30 只肥胖大鼠按1:2比例,随机选取10 只大鼠为肥胖组,20 只肥胖大鼠牙周丝线结扎建立肥胖复合牙周炎模型(复合组),结扎后有4 只大鼠死亡.在牙周结扎前、结扎1 周、4 周3 个时间点眼眶静脉取血,检测空腹血糖及空腹胰岛素,并计算HOMA-IR及β细胞功能指数(HOMA-β);ELISA检测血清CRP水平.结果:牙周结扎1 周后,复合组CRP水平显著升高,在结扎4 周时则逐渐回落(F=7.773,P=0.004).牙周结扎后4 周,复合组HOMA-IR显著高于肥胖组(F=-4.691,P=0.000),HOMA-β显著低于对照组(F=3.672,P=0.002).结论:实验性牙周炎影响肥胖大鼠血清CRP水平;实验性牙周炎会加重肥胖大鼠的胰岛素抵抗状态并下调β细胞功能.

The effects of experimental periodontitis on serum C reactive protein and insulin resistance in obese rats

Objective:To investigate the effects of experimental periodontitis on serum C reactive protein(CRP) and insulin resistance in obese rats.Methods:4 week old SD rats (n=35)were fed with high fat diet for 16 weeks to establish the model of obesity.According to the obesity criteria,5 rats were screened out.According to the proportion of 1:2,10 rats were randomly selected as obese control group,20 obese rats were used for the establishment of the obesity with periodontitis model(combination group) by periodontal ligation using silk thread.4 rats died after ligation.Before periodontal ligation,1 and 4 weeks after periodontal ligation,orbital venous blood were collected for the detection of fasting blood glucose and fasting insulin.Homeostasis model assessments of insulin resistance index(HOMA-IR) and beta cell function index(HOMA-β) were calculated.The level of serum CRP was examined by ELISA.Results:The level of CRP in the combination group was increased 1 week after periodontal ligation,and then gradually decreased in the following 4 weeks(F=7.773,P=0.004).HOMA-IR in the combination group were higher than that in the obese group(F=-4.691,P=0.000),and beta cell function index was significantly lower(F=3.672,P=0.002) than that in the control group 4 weeks after periodontal ligation.Conclusion:The experimental periodontitis may affect the serum level of CRP in obese rats,aggravate insulin resistance and decrease the function of beta cells in obese rats.