Effects of adiponectin pretreatment on liver injury in endotoxemic rats

Objective To investigate the effect of adiponectin pretreatment on liver injury in endotoxemic rats.Methods Eighty male Wistar rats,aged 10-14 weeks,weighing 250-300 g,were randomly divided into 4 groups (n =20 each):control group (C group),lipopolysaccharide (LPS) group,adiponectin pretreatment group (APN group) and interlukin-10 (IL-10) neutralizing antibody intervention group (IL-10 antibody group).Endotoxemia was induced by intraperitoneal LPS 20 mg/kg in LPS,APN and IL-10 antibody groups.In groups APN and IL-10 antibody,intraperitoneal adiponectin 6 mg/kg was injected at 12 h before LPS administration.IL-10 neutralizing antibody 3 mg was injected intraperitoneally at 30 min before adiponectin administration in group IL-10 antibody.Ten rats in each group were chosen at 2 h after LPS administration and blood samples were collected from the hearts for determination of the serum levels of alanine aminotransferase (ALT),aspartate transaminase (AST),tumor necrosis factor (TNF)-α,IL-1β and IL-10.Auother 10 rats in each group were chosen at 2 h after LPS administration and sacrificed and the livers were removed for determination of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity and expression of IL-10 mRNA and heme oxygenase-1 (HO-1) mRNA in liver tissues.Results Compared with C group,the serum levels of ALT,AST,TNF-α,IL-1β and IL-10,MDA content and MPO activity in liver tissues were significantly increased,and HO-1 mRNA expression in liver tissues was upregulated in groups LPS,APN and IL-10 antibody and IL-10 mRNA in liver tissue was up-regulated in LPS and APN groups (P ＜ 0.05).Compared with LPS group,the serum levels of ALT,AST,TNF-α and IL-1β,MDA content and MPO activity in liver tissues were significantly decreased,and HO-1 mRNA expression in liver tissues was up-regulated in APN and IL-10 antiboby groups and IL-10 mRNA in liver tissue was up-regulated in APN group (P ＜ 0.05).Compared with APN group,the serum levels of ALT,AST,TNF-α and IL-1β,MDA content and MPO activity in liver tissues were increased,while the serum level of IL-10 and HO-1 mRNA expression in liver tissues were decreased in IL-10 antiboby group (P ＜ 0.05).Conclusion Adiponectin pretreatment can attenuate liver injury in endotoxic rats by inducing IL-10 production. Key words: Adiponectin;  Endotoxemia;  Liver injury