title: Ghrelin Protects against Dexamethasone-Induced INS-1 Cell Apoptosis via ERK and p38MAPK Signaling.
abstract: Glucocorticoid excess induces apoptosis of islet cells, which may result in diabetes. In this study, we investigated the protective effect of ghrelin on dexamethasone-induced INS-1 cell apoptosis. Our data showed that ghrelin (0.1 μM) inhibited dexamethasone-induced (0.1 μM) apoptosis of INS-1 cells and facilitated cell proliferation. Moreover, ghrelin upregulated Bcl-2 expression, downregulated Bax expression, and decreased caspase-3 activity. The protective effect of ghrelin against dexamethasone-induced INS-1 cell apoptosis was mediated via growth hormone secretagogue receptor 1a. Further studies revealed that ghrelin increased ERK activation and decreased p38MAPK expression after dexamethasone treatment. Ghrelin-mediated protection of dexamethasone-induced apoptosis of INS-1 cells was attenuated using the ERK inhibitor U0126 (10 μM), and cell viability increased using the p38MAPK inhibitor SB203580 (10 μM). In conclusion, ghrelin could protect against dexamethasone-induced INS-1 cell apoptosis, at least partially via GHS-R1a and the signaling pathway of ERK and p38MAPK.
authors.affiliation: Hepatobiliary Surgery Department and Unit of Organ Transplantation, First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Chengshuo
authors.identifier: 0000-0001-9679-5271
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Hepatobiliary Surgery Department, Chifeng Municipal Hospital, Chifeng 024000, China.
authors.forename: Le
authors.identifier: 0000-0003-3418-6846
authors.initials: L
authors.lastname: Li
authors.affiliation: Hepatobiliary Surgery Department and Unit of Organ Transplantation, First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Bochao
authors.identifier: 0000-0002-2198-8674
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Hepatobiliary Surgery Department and Unit of Organ Transplantation, First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Ao
authors.identifier: 0000-0003-1039-5272
authors.initials: A
authors.lastname: Jiao
authors.affiliation: Department of General Surgery, Fourth Hospital of China Medical University, Shenyang 110032, China.
authors.forename: Xin
authors.identifier: 0000-0003-0086-4282
authors.initials: X
authors.lastname: Li
authors.affiliation: Hepatobiliary Surgery Department and Unit of Organ Transplantation, First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Ning
authors.identifier: 0000-0002-7496-6196
authors.initials: N
authors.lastname: Sun
authors.affiliation: Hepatobiliary Surgery Department and Unit of Organ Transplantation, First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Jialin
authors.identifier: 0000-0003-2617-2735
authors.initials: J
authors.lastname: Zhang