Bacillus subtilis alleviates excessive apoptosis of intestinal epithelial cells in intrauterine growth restriction suckling piglets via the members of Bcl-2 and caspase families.

Abstract

The intestine is a barrier resisting various stress responses. Intrauterine growth restriction (IUGR) can cause the damage of intestinal barrier via destroying the balance of intestinal epithelial cells' proliferation and apoptosis. Bacillus subtilis has been reported to regulate intestinal epithelial cells' proliferation and apoptosis. Thus, the purpose of the current study was to determine if B. subtilis could regulate intestinal epithelial cells' proliferation and apoptosis in intrauterine growth restriction suckling piglets. Compared with normal birth weight group, IUGR group showed greater mean optical density values of Ki-67 positive cells in the ileal crypt (P < 0.05). IUGR resulted in higher ability of proliferation and apoptosis of intestinal epithelial cells, by up-regulation of the mRNA or proteins expression of leucine rich repeat containing G protein coupled receptor 5, Caspase-3, Caspase-7, β-catenin, cyclinD1, B-cell lymphoma-2 associated agonist of cell death, and BCL2 associated X (P < 0.05), and down-regulation of the mRNA or protein expression of B-cell lymphoma-2 and B-cell lymphoma-2-like 1 (P < 0.05). However, B. subtilis supplementation decreased the mRNA or proteins expression of leucine rich repeat containing G protein coupled receptor 5, SPARC related modular calcium binding 2, tumor necrosis factor receptor superfamily member 19, cyclinD1, Caspase-7, β-catenin, B-cell lymphoma-2 associated agonist of cell death, and Caspase-3 (P < 0.05), and increased the mRNA expression of B-cell lymphoma-2 (P < 0.05). IUGR led to excessive apoptosis of intestinal epithelial cells, which induced compensatory proliferation. However, B. subtilis treatment prevented intestinal epithelial cells of IUGR suckling piglets from excessive apoptosis. This article is protected by copyright. All rights reserved.