Effects of chronic intermittent hypoxia on hepatic function and protective mechanism of adiponectin in rats

Abstract

Objective: To explore the effect of chronic intermittent hypoxia (CIH) on rats hepatic function, and the protective mechanism of adiponectin (Ad). Methods: Sixty healthy male wistar rats were randomly divided into 4 groups: normal control (NC), NC+ Ad, CIH, and CIH+ Ad groups with 15 rats in each. The rats in CIH and CIH+ Ad groups were exposed to an intermittent hypoxic chamber 8 hours per day for 4 months. Meanwhile, the rats in both the NC and NC + Ad groups were housed with normal pressure air. The rats in the NC+ Ad and CIH+ Ad groups were additionally treated with an intravenous injection of Ad (10 μg), twice a week for 4 months. At the end of experiment, comparison among groups was made about plasma levels of aspartate amino transferase (AST), alanine amino transferase (ALT), degrees of endoplasmic reticulum stress (ERS) and mitochondrium associated cellular apoptosis. Results: No significant difference was detected in all items between NC and NC+ Ad groups (all P>0.05). Plasma hepatic enzyme levels of AST and ALT were significantly higher in CIH group [(319±21) and (113±9) U/L] than those in NC group [(178±19) and (51±9) U/L] and NC+ Ad group [(175±16) and (52±8) U/L] (all P<0.05). Compared NC with NC+ Ad group, there was more remarkable ERS and mitochondrial injury associated cellular apoptosis in hepatic tissues of CIH group. Such pathological changes were less obvious in CIH+ Ad group than in CIH group (all P<0.05). Conclusion: CIH can induce hepatic injury in rats, while Ad supplement may play a protective role possibly through inhibition of ERS and associated pathways of cellular apoptosis.