Liraglutide protects pancreatic β cells from endoplasmic reticulum stress by upregulating MANF to promote autophagy turnover
Liraglutide protects pancreatic β cells from endoplasmic reticulum stress by upregulating MANF to promote autophagy turnover
复制标题
利拉鲁肽通过上调 MANF 促进自噬周转来保护胰腺 β 细胞免受内质网应激
DOI：
10.1016/j.lfs.2020.117648
复制
发表时间：
2020-07-01
期刊：
影响因子：
6.1
通讯作者：
Liu, Dongfang
中科院分区：
文献类型：
--
作者：
Fu, Jili;Nchambi, Kija Malale;Liu, Dongfang
目的：探讨中脑星形胶质细胞源性神经营养因子(MANF)与自噬和内质网(ER)应激的关系，以及利拉鲁肽(LRG)是否通过调节MANF的表达来保护β细胞、促进自噬和缓解ER应激。主要方法：采集健康对照组(NC)、单纯高脂血症(HLD)和初诊2型糖尿病(T2D)患者的血清标本。用双抗体夹心法检测MANF水平。体外用葡萄糖(GLU)、棕榈酸酯(PA)、胡萝卜素(TG)、LRG和氯喹(CQ)处理小鼠胰岛MIN6细胞后，用细胞计数试剂盒8(CCK-8)检测细胞增殖，Western blotting检测细胞凋亡相关蛋白C-cas-3、内质网应激和自噬相关蛋白，免疫荧光法检测MANF、胰岛素和C-cas-3蛋白的表达。主要发现：与NC组相比，HLD组和T2D组的MANF水平显著升高。GLU、PA和TG诱导内质网应激后，细胞存活率下降，而MANF、c-Cas3、ERS和自噬相关蛋白增加，这与GLU、PA和TG的浓度有关。与BSA组相比，PA组线粒体和自噬小体数量增多，线粒体受损。在PA组和TG+CQ组，这种作用进一步被夸大。但经LRG联合处理后，GLU、PA和TG的作用减弱。意义：LRG通过上调MANF促进自噬转换来保护胰岛β细胞免受内质网应激的影响。
Aims: This study was conducted to determine the relationship between mesencephalic astrocyte-derived neurotrophic factor (MANF), autophagy and endoplasmic reticulum (ER) stress, and whether liraglutide (LRG) can protect beta cells, promote autophagy and alleviate ER stress by regulating MANF expression.Main methods: Human serum samples were collected from healthy controls (NC), simple hyperlipidemia (HLD), and newly diagnosed type 2 diabetes (T2D). The MANF levels were detected using ELISA. In vitro, after the mouse islet MIN6 cells were treated with glucose (GLU), palmitate (PA), thapsigargin (TG), LRG, and chloroquine (CQ), cell proliferation was detected using cell counting kit-8 (CCK-8), apoptosis-related protein cleaved caspase 3 (C-cas-3), ER stress, and autophagy-related proteins were detected by Western blotting, MANF, insulin, and C-cas-3 proteins were detected via immunofluorescence. Subcellular structures and autophagosomes were examined using electron microscopy.Key findings: Compared with the NC group, the MANF levels in the HLD and T2D groups increased significantly. After ER stress induced by GLU, PA, and TG, cell viability decreased, while MANF, c-cas3, ERS, and autophagy-related proteins increased, which was related to the concentration of GLU, PA, and TG. Compared with the BSA group, the number of mitochondria and autophagosomes in the PA group increased and the mitochondria were damaged. In the PA and TG plus CQ groups, the effect was further exaggerated. But after co-treatment with LRG, the effects of GLU, PA, and TG were attenuated.Significance: LRG protects islet beta cells from ER stress by upregulating MANF to promote autophagy turnover.