Exendin-4对h IAPP诱导的胰岛β细胞凋亡的保护作用  

The protective effect of Exendin-4 on hIAPP-induced apoptosis of pancreatic β-cells

作　　者：刘辰 梁倩雯 赵济全[1] LIU Chen;LIANG Qianwen;ZHAO Jiquan(Department of Doctor-Patient Relations,the Eighth Affiliated Hospital,Sun Yat-Sen University,Shenzhen 518033,China)

机构地区：[1]中山大学附属第八医院医务部医患关系科,518033

出　　处：《天津医药》2022年第6期578-582,共5页Tianjin Medical Journal

基　　金：广东省自然科学基金项目(2017A030313766)。

摘　　要：目的探究Exendin-4对人源胰岛淀粉样多肽(h IAPP)诱导的胰岛β细胞凋亡的保护作用及其可能的作用机制。方法体外培养胰岛β细胞INS-1E,加入2.5、5、10、20μmol/L的hIAPP培养48 h,建立hIAPP诱导细胞凋亡模型。20、50、100 nmol/L Exendin-4预处理24 h,CCK-8法检测细胞活力,筛选有效的药物剂量。随后实验分为空白组、Exendin-4组、h IAPP模型组、h IAPP+Exendin-4组以及阳性对照组。LDH释放检测法分析膜通透性变化;化学发光法测定细胞内腺苷三磷酸(ATP)水平;JC-1荧光探针法检测线粒体膜电位的改变;Western blot检测线粒体凋亡相关蛋白Bcl-2、Bax以及Bad的表达。结果20μmol/L的hIAPP可以明显抑制INS-1E细胞增殖,增加LDH的释放,增加细胞内ATP的消耗,增加去极化线粒体膜电位比例,下调抗凋亡蛋白Bcl-2的表达,上调促凋亡蛋白Bax和Bad的表达(均P<0.05)。与hIAPP组相比,h IAPP+Exendin-4组能够显著提高细胞活力,减少LDH释放,缓解ATP消耗,降低去极化线粒体膜电位的比例,上调Bcl-2并下调Bax和Bad的蛋白表达(均P<0.05)。同时单独应用Exendin-4不会对细胞的生长产生影响。结论Exendin-4对由hIAPP诱导的胰岛β细胞凋亡具有保护作用,其机制与抑制线粒体凋亡途径相关。Objective induced pancreaticβ-cell apoptosis and its possible mechanism.Methods INS-1E cells were cultured with 2.5,5,10,20μmol/L hIAPP to establish apoptosis model.Exendin-420,50 and 100 nmol/L pretreated for 24 h followed by hIAPPtreatment for 48 h.CCK-8 assay was used to detect cell viability and to screen effective dosage.Experiments were dividedinto the control group,the Exendin-4 group,the h IAPP group and the h IAPP+Exendin-4 group.The change of membranepermeability was detected by LDH release detection kit and the generation of intracellular ATP was detected bychemiluminescence assay.JC-1 fluorescence probe was used to detect the change of mitochondrial membrane potential.Western blot assay was used to detect the expression of mitochondrial apoptosis-related proteins Bcl-2,Bax and Bad.Results Compared to the control group,h IAPP(20μmol/L)can significantly inhibit cell proliferation,increase LDHrelease and intracellular ATP consumption,increase the ratio of depolarized mitochondrial membrane potential,down-regulate Bcl-2 expression,and up-regulate Bax and Bad protein(P<0.05).However,h IAPP+Exendin-4 group cansignificantly improve cell viability,reduce LDH release,increase ATP production,reduce the proportion of depolarizedmitochondrial membrane potential,up-regulate Bcl-2 and down-regulate the expression of Bax and Bad protein(P<0.05).Exendin-4 alone had no effect on cell growth.Conclusion Exendin-4 has a protective effect on h IAPP-induced apoptosisof pancreaticβ-cells,which is related to the inhibition of mitochondrial apoptosis pathway.

关 键 词：胰岛淀粉样多肽 胰岛素分泌细胞 细胞凋亡 EXENDIN-4 胰岛Β细胞 线粒体凋亡 

分 类 号：R587.1[医药卫生—内分泌]