限制能量摄入对大鼠胰岛细胞衰老及胰岛素表达的影响

Effect of caloric restriction on cell senescence and insulin expression of pancreatic islets

目的探讨限制能量摄入对大鼠胰岛细胞衰老及胰岛素表达的影响。方法18月龄SD大鼠经过限制能量摄入（给予正常饮食量的60%）6个月,建立限制能量摄入动物模型。取限制能量摄入组（实验组）及对照组胰腺,行β-半乳糖苷酶（SA-β-Gal）染色并检测胰岛内p16的表达,以了解胰岛细胞衰老状态；同时检测胰岛B细胞胰岛素的表达。结果实验组与对照组比较。胰岛内p16表达减少,分别为（0.19130±0.02852）个和（0.24526±0.03191）个,差异有统计学意义（P〈 0.01）；胰岛内β-Gal染色阳性率分别为84%和100%（P〈0.01）、着色面积1.672和2.118（P〈 0.05）、着色程度1.725和2.412（P〈0.05）；胰岛素表达增加（201.7±35.3和187.8±26.0）,差异有统计学意义（P〈0.05）结论限制能量摄入可延缓胰岛B细胞衰老,改善胰岛的分泌功能。

Objective To investigate the effect of caloric restriction （CR） on pancreatic beta cell senescence and its insulin secretion. Methods Eighteen-month-old SD rats received calory restriction （60% of regular intake） for 6 months. Rats of calory-restricted group and control group were killed at the end of the study, and sections of pancreas were stained for senescence-associated β-galactosidase （SA-β-Gal） and stained immunohistochemically with anti-p16 antibody to identify cell senescence of pancreatic islets, and stained immunohistoehemically with anti-insulin antibody. Results SA-β-Gal stain （presence, frequency, extent） decreased in calory-restricted rats （presence： 84%, frequency： 1.672, extent.. 1.725） compared with control group （presence： 100%, frequency： 2. 118, extent： 2. 412）（all P〈0. 05）. p16 expression was lower in calory-restricted rats compared with control group （0. 19130 ± 0. 02852 vs. 0. 24526±0. 03198, P〈0.01）. Insulin expression was higher in CR group compared with control group （ 201.7 ± 35.3 vs. 187.8 ± 26. 0, P 〈0. 05 ）. Conclusions Calory resiriction can slow down the pancreatic beta cell senescence and improve insulin secretion of pancreatic islets.