Xiangbing Mao;Man Ren;Daiwen Chen;Bing Yu;Lianqiang Che;Jun He;Junqiu Luo;Yuheng Luo;Jianping Wang;Hui Su

College of Animal Science and Technology, Jilin Agricultural University, Changchun 130033, Chin;Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014, China; Corresponding authors.;Animal Science Collage, Anhui Science and Technology University, Chuzhou 233100, China

leucine;proteins;phagocytosis;metabolism;treatment;cell proliferatio

Leucine can affect intestinal protein expressions, and improve mucosal immune function. However, little study has been conducted to determine the change of protein component by leucine treatment in intestine epithelial cells. The present study was to cover the key proteins and cell pathways that could be regulated by leucine treatment in porcine intestinal epithelial cell line (IPEC-J2) cells with the approach of proteome analysis. A total number of 3,211 proteins were identified in our approach by searching the database of Uniprot sus scrofa. Among identified proteins, there were 101 proteins expressed differently between control group and leucine group. Compared with the control group, there were 50 up-regulated proteins and 51 down-regulated proteins in leucine group. In these proteins, leucine treatment decreased the expression of some proteins including pyruvate kinase, glyceraldehyde-3-phosphate dehydrogenase, E3 ubiquitin ligase, cathepsin D, caspase 3 and caspase 6, and increased the levels of some proteins, such as some eukaryotic translation initiation factors, ubiquitin carboxyl-terminal hydrolase, DNA-related RNA polymerase II, urokinase plasminogen activator, cyclin-dependent kinase inhibitor 2b, MutL homolog 1, 5-methylcytosine binding domain 4, polymerase δ, α-tubulin, syntaxin 18, Ras homolog D, actin related protein 2/3 complex and cofilin. Via the analysis of Gene Ontology and pathways, these proteins in IPEC-J2 cells were related with some physiological functions, such as protein metabolism, glycolysis, cell proliferation, apoptosis and phagocytosis. Thus, these results suggest that leucine affects gut barrier function possibly via regulating cell proliferation and apoptosis, metabolism and phagocytosis.