Milk derived hexapeptide reduces alcohol －induced oxidative stress and alleviates liver injury through FoxO3a －MnSOD signaling pathway / 安徽医科大学学报

ABSTRACT

Objective @#To investing ate the milk-derived hexapeptide PGPIPN and its truncated pentapeptide PGPIP to alleviate chronic alcoholic liver injury in mice and its associated molecular mechanisms．@*Methods @#Sixty Kun- ming mice were randomly divided into control group，model group，GSH group，PGPIPN group，and truncated pen- tapeptide PGPIP group．The model of chronic alcoholic liver injury in mice was established by gavage with gradient alcohol． Drug intervention was given at the same time for 12 weeks． Liver HE staining was used to analyze the pathological effects of each treatment group on alcoholic liver injury in mice．Primary mouse hepatocytes and human normal hepatocyte line L-02 were isolated and cultured in vitro．The appropriate PGPIPN induction concentrations of both cells were determined by WST-1 method． L-02 cells were induced at different times． The expression of FoxO3a and phosphorylated FoxO3a protein were detected by Western blot to determine the appropriate induction time．The subcellular localization of FoxO3a in L-02 cells was detected by cellular immunofluorescence．The mR- NA changes of FoxO3a and MnSOD genes in primary hepatocytes and L-02 cells of mice in different treatment groups were detected by qRT-PCR.@*Results @#The pathological examination of PGPIPN group and PGPIP group was similar to that of GSH group，and the liver injury of mice was significantly reduced．Medium and high concentra- tions of PGPIPN were respectively selected to induce mouse primary hepatocytes and L-02 cells．At 16 hours，the expression of FoxO3a protein in L-02 cells increased significantly．FoxO3a protein was mainly expressed in the nu- cleus．In addition，mRNA levels in both types of cells increased significantly after induction with the corresponding dose of PGPIPN．@*Conclusion @#PGPIPN and truncated pentapeptide PGPIP can reduce chronic alcoholic liver injury in mice．The mechanism may be to reduce alcohol-induced oxidative stress through FoxO3a-MnSOD signaling path- way.