title: The Effects of Glucagon-like Peptide-2 on the Tight Junction and Barrier Function in IPEC-J2 Cells through Phosphatidylinositol 3-kinase-Protein Kinase B-Mammalian Target of Rapamycin Signaling Pathway.
abstract: Glucagon-like peptide-2 (GLP-2) is important for intestinal barrier function and regulation of tight junction (TJ) proteins, but the intracellular mechanisms of action remain undefined. The purpose of this research was to determine the protective effect of GLP-2 mediated TJ and transepithelial electrical resistance (TER) in lipopolysaccharide (LPS) stressed IPEC-J2 cells and to test the hypothesis that GLP-2 regulate TJ and TER through the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt)-mammalian target of rapamycin (mTOR) signaling pathway in IPEC-J2 cells. Wortmannin and LY294002 are specific inhibitors of PI3K. The results showed that 100 μg/mL LPS stress decreased TER and TJ proteins occludin, claudin-1 and zonula occludens protein 1 (ZO-1) mRNA, proteins expressions (p<0.01) respectively. GLP-2 (100 nmol/L) promote TER and TJ proteins occludin, claudin-1, and zo-1 mRNA, proteins expressions in LPS stressed and normal IPEC-J2 cells (p<0.01) respectively. In normal cells, both wortmannin and LY294002, PI3K inhibitors, prevented the mRNA and protein expressions of Akt and mTOR increase induced by GLP-2 (p<0.01) following with the significant decreasing of occludin, claudin-1, ZO-1 mRNA and proteins expressions and TER (p<0.01). In conclusion, these results indicated that GLP-2 can promote TJ's expression and TER in LPS stressed and normal IPEC-J2 cells and GLP-2 could regulate TJ and TER through the PI3K/Akt/mTOR pathway.
authors.affiliation: Key Laboratory of Animal Disease-Resistance Nutrition and Feed Science, Ministry of Agriculture, Ya'an, Sichuan 625014, China.
authors.forename: Changsong
authors.initials: C
authors.lastname: Yu
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Jia
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Qiuhong
authors.initials: Q
authors.lastname: Deng
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Chen
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Guangmang
authors.initials: G
authors.lastname: Liu
authors.affiliation: Animal Nutrition Institute, Sichuan Agricultural University, Ya'an, Sichuan 625014, China.
authors.forename: Kangning
authors.initials: K
authors.lastname: Wang
keywords: Glucagon-like Peptide-2; IPEC-J2 Cell; Phosphatidylinositol 3-Kinase-Akt-mTOR Signaling Pathway; Tight Junction; Transepithelial Electrical Resistance