The Effect Of Experimental Periodontitis And Non-surgical Periodontal Therapy On Serum Inflammatory Factors And Insulin Resistance In Obese Rats

Chapter 1 Establishment of a combined model of obesity and periodontitis in ratsObjectiveTo establish a combined model of obesity and periodontitisin ratsMethods,4-week-aged male SD rats were randomly divided into normal diet group and high fat diet group.16 weeks.later,a total of 30 obese rats were selected,and then randomly divided into the obese control group(N=10)and the combined obesity with periodontitis group(the combined group,N = 20).At the age of 20 weeks,the bilateral maxillary second molars of the rats in the combined group were ligated with 3-0 silk thread to induce experimental periodontitis.Results(1)The average body weights of rats in high fat diet group were significantly higher than that in normal diet group by 15%.(2)The pathological examinations showedthere were ulcerations in the gingival epithelial barriers,proliferation of the conjunctional epithelium to the root,formation of periodontal pockets,and loss of alveolar bone,indicating successful establishment of the combined model of obesity and periodontitis.ConclusionThe high fat diet could induce a model of obesityin rats.,Periodontal ligationsin obese rats could induceestablishment of a combined animal model of obesity and periodontitis.Chapter 2 The effect of experimental periodontitis on serum C-reactive protein(CRP)and insulin resistance in obese ratsObjectiveTo investigate the effects of experimental periodontitis on serum C reactive protein(CRP)and insulin resistance in obese rats..Methods2 mL blood were collected from parallel fundus venous,before ligation,1 weeks after ligation,and 4 weeks after ligation,in both groups to test fasting blood glucose,fasting insulin,glycosylated hemoglobin.The HOMA-IR,HOMA-B were calculated.Enzyme linked immunosorbent assay was used to detect the level of serum CRP.Results(1)The HOMA-IR in combined group(30.29±4.77)was significantly higher than that in the control group(21.95±2.97),while the HOMA-P in combined group(755.36±98.11)was significantly lower than that in obese control group(913.53±94.50),4 weeks after the ligation.(2)1 week After the ligation,the CRP level in the combined group(203.78±53.71 ng/mL)was significantly higher than that in control group(156.37±33.84ng/mL).Conclusion(1)Experimental periodontitis could aggravate the insulin resistance and down-regulate the function of B cellsin obese rats.(2)The experimental periodontitis affected serum CRP level in rats in the acute phase.Chapter 3 Effect of non-surgical periodontal therapy on the serum inflammatory factors and insulin resistance in obese ratsObjectiveTo investigate the effects of non-surgical periodontal therapy on serum inflammatory factors and insulin resistance in obese rats.MethodsA total of 16 rats were divided into two groups according to their weight sequence.Rats in the treatment group(n = 8)were treated with the removal of the silk thread and periodontal irrigation.Rats in the untreated group(n = 8)had not received any intervention.2 weeks after treatment,OGTT tests were undertaken in the rats.2mL blood from fundus orbital venous were taken to detect fasting blood glucose,fasting insulin,glycosylated hemoglobin.The HOMA-IR,HOMA-? were calculated.And the serum CRP levels were determined by enzyme linked immunosorbent assay.Results(1)The fasting blood glucose(5.06±0.69 mmol/L)in the treatment group was significantly lower than that in the untreated group(5.61±0.19mmol/L),The HOMA-?(974.54±419.37)was significantly higher than that in the untreated group(645.37±73.47).(2)The CRP in the treatment group(140.99±32.10 ng/mL)was lower than that in the untreated group(173.43 + 28.54ng/mL)(3)In the OGTT test,the blood glucose levels of 60min and 120min in the treatment group were significantly lower than those in the untreated group.And the area under the glucose curve(9.62±10.57)in treatment group was significantly lower than that in the untreated group(12.59±0.58).ConclusionNon-surgical periodontal therapy could down-regulate the serum CRPlevel,improve the function of islet beta cells and improve the glucose tolerance.