Janus相关激酶2基因缺失对胰岛β细胞存活及其功能的影响  

Effect of Janus kinase 2 depletion on pancreatic 13 cell survival and function

作　　者：何晓玉 熊飞[1] Kay-Uwe Wagner 王从义[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院生物医学研究中心,武汉430030 [2]美国内布拉斯加大学医学中心

出　　处：《中华糖尿病杂志》2017年第10期612-616,共5页CHINESE JOURNAL OF DIABETES MELLITUS

基　　金：国家自然科学基金资助项目（81500637）

摘　　要：目的 探讨Janus相关激酶2（Jak2）对小鼠胰岛β细胞存活及其功能的影响.方法 将诱导型胰岛β细胞特异性Cre转基因小鼠（Rip-CreER tg）与条件性Jak2基因敲除小鼠（Jak2f/f）反复杂交后得到Rip-CreER-Jak2f/f后代,Rip-CreER阳性Jak2双Loxp的雄性小鼠（Rip-CreER-Jak2f/f）为实验组（KO组,40只）,同窝生的Rip-CreER阴性Jak2f/f雄性小鼠作为对照组（40只）.KO组与对照组小鼠体重20-22 g,鼠龄8周.KO组于8周时腹腔注射他莫昔芬诱导β细胞特异性敲除Jak2基因,对照组给予同样剂量他莫昔芬诱导,在他莫昔芬诱导后一周开始实验检测.采用聚合酶链反应及Western blotting分析检测Jak2在β细胞中的表达缺失,监测小鼠随机血糖及腹腔糖耐量实验评价小鼠胰岛功能.给予KO组和对照组小鼠不同剂量的链脲佐菌素（STZ）刺激,观察Jak2对β细胞存活的调节作用.两两比较采用独立样本的t检验进行统计分析,糖尿病发病率及小鼠病死率用Kaplan-Meier生存模型进行分析.结果 成功建立了诱导型胰岛β细胞特异性敲除Jak2小鼠模型.随机血糖监测发现KO组小鼠无自发糖尿病.KO组与对照组小鼠在150 mg/kg的STZ刺激下,糖尿病发生率差异无统计学意义（83.3%比91.6%,P=0.3928）.在亚致病剂量100 mg/kg的STZ刺激下两组小鼠的糖尿病发病率均为20%,2组平均血糖值差异无统计学意义[（11.0 ± 6.6）比（12.0 ± 5.7）mmol/L,t=0.7931,P=0.4258].给予KO组及对照组小鼠致死剂量250 mg/kg的STZ刺激,KO组与对照组小鼠死亡率在给药后第25天无统计学差异（92.3%比93.75%,P=0.5540）.结论 小鼠胰岛β细胞的Jak2基因高表达,但对β细胞的存活及功能无影响.Objective To explore the effects of Janus kinase 2 （Jak2） depletion on pancreatic β cell survival and function. Methods Rip-CreER-Jak2f/fmale mice hybridized by Rip-CreER mice and Jak2f/fmice （8 weeks old and 20-22 grams weight） were induced by tamoxifen to generate β cell-specific Jak2 knockout（KO）mice（KO group,n=40）.Jak2f/fmale mice induced by tamoxifen were as control group（n=40）. Jak2 gene depleted at day 7 after tamoxifen-induction and confirmed by Polymerase chain reaction （PCR） and western blotting analyses. β cell function were evaluated by random glucose levels and intraperitoneal glucose tolerance test （IPGTT）. The pathogenic, sub-pathogenic and lethal doses of streptozocin （STZ） were administrated respectively to observe the effects of Jak2 on β cell survival. Comparison of the two treatments were analyzed using the student＇s t-test,the incidence of diabetes and the mortality of mice were analyzed by Kaplan-Meier survival model. Results Inducible pancreatic β cell-specific Jak2 knockout mouse model were established successfully. None of the KO mice developed diabetes spontaneously.There were no significant differences in the incidence of diabetes between KO and control mice either stimulated with pathogenic or sub-pathogenic doses of STZ（83.3% vs 91.6%,P=0.392 8;20% vs 20%, P〉0.05; respectively）; No significant differences were found in the average glucose levels between KO and control mice [（11.0 ± 6.6） vs （12.0 ± 5.7） mmol/L, P=0.425 8]. There were no significant differences in the motility rate between KO and control mice when stimulated with lethal dose of STZ（92.3% vs 93.75%,P=0.554 0）.Conclusion Jak2 gene is highly expressed in pancreatic β cell,however,Jak2 has no effects on β cell survival and function.

关 键 词：JAK2基因 Β细胞 氧化应激 胰岛功能 

分 类 号：R587.1[医药卫生—内分泌]