Feng M, Li J, Wang J, Ma C, Jiao Y, Wang Y, Zhang J, Sun Q, Ju Y, Gao L, Zhao Y. High glucose increases LPS-induced DC apoptosis through modulation of ERK1/2, AKT and Bax/Bcl-2.
BMC Gastroenterol 2014;
14:98. [PMID:
24885625 PMCID:
PMC4081508 DOI:
10.1186/1471-230x-14-98]
[Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 05/14/2014] [Indexed: 01/27/2023] Open
Abstract
Background
This study investigates the effect of glucose on the LPS-induced apoptosis of dendritic cells in the intestinal tract of mice and the dendritic cell line DC2.4.
Methods
Flow cytometry was used to detect dendritic cell apoptosis both in vivo and in vitro. Hoechst 33258 staining was used to detect the morphological changes characteristic of apoptotic nuclei. Expression of apoptosis related proteins was investigated by western blot analysis and immunohistochemistry.
Results
Pretreatment with a high concentration of glucose increased apoptosis of LPS-treated dendritic cells both in vivo and in vitro at 24 h. No effect was evident at the earlier time points of 15 min and 6 h in vitro. Furthermore, at 24 hours the expression of the survival proteins AKT, ERK and Bcl-2 was decreased, while the expression of the proapoptotic protein Bax was increased. AKT, ERK, Bcl-2 and Bax were mainly located in the cytoplasm by immunohistochemistry.
Conclusions
These results suggest that high glucose concentrations might prime dendritic cells for apoptosis induced by LPS in the intestinal tract through upregulating the expression of Bax and downregulating the expression of AKT, ERK and Bcl-2. Therefore, this study may give clues to understanding the immunological mechanism behind gastrointestinal complications in diabetes mellitus.
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