Melatonin ameliorates ANIT‑induced cholestasis by activating Nrf2 through a PI3K/Akt‑dependent pathway in rats

Abstract

Cholestasis is a devastating liver condition which is increasing in prevalence worldwide; however, its underlying pathogenic mechanisms remain to be fully elucidated. It was hypothesised that melatonin may alleviate the hepatic injury associated with cholestasis due to its established antioxidant effects. Therefore, the effect and potential anticholestatic properties of melatonin were investigated in rats with α-naphthylisothiocyanate (ANIT)-induced liver injury, a common animal model that mimics the cholestasis-associated liver injury in humans. The rats received intraperitoneal injection of ANIT with or without subsequent treatment with melatonin, and were sacrificed 24 h later. The serum biochemistry parameters of the liver were measured using conventional laboratory assays, and the liver tissue was subjected to conventional histological examination, reverse transcription-quantitative polymerase chain reaction analysis and western blotting. The levels of alanine transaminase, aspartate transaminase, total bilirubin, direct bilirubin, total bile acids, alkaline phosphatase, γ-glutamyl transferase and glutathione were restored in rats treated with melatonin. Histological examination provided further evidence supporting the protective effect of melatonin against ANIT-induced cholestasis. In addition, the mRNA and protein expression levels of glutamate cysteine ligase, phosphorylated Akt and nuclear factor-erythroid 2-related factor-2 were restored in rats treated with melatonin. These findings indicate that melatonin is a natural agent that appears to be promising for the treatment of cholestasis, and that the anticholestatic effects of melatonin involve the alleviation of oxidative stress.

iTRAQ‑based quantitative proteomics analysis of the hepatoprotective effect of melatonin on ANIT‑induced cholestasis in rats

“…1F ). These results were consistent with those of previous studies by our group ( 11 , 12 ). For each group, 6 random fields of view were statistically evaluated for inflammatory lesions (examples in Fig.…”

“…Long-term biliary obstruction may cause liver damage, even induce biliary cirrhosis or liver fibrosis and, in severe cases, may lead to liver failure ( 25 ). In recent years, it has been indicated that oxidative stress and abnormal fatty acid metabolism may be involved in the pathogenesis of intrahepatic cholestasis ( 11 , 12 , 24 , 26 ). Previously, melatonin has been demonstrated to improve liver fibrosis and liver damage caused by various diseases through inhibiting oxidative damage ( 10 ).…”

“…There are numerous studies suggesting that melatonin may be used to treat liver disease and the hepatoprotective effects of melatonin may be associated with its antioxidant properties ( 10 ). Previous studies by our group demonstrated that the therapeutic effects of melatonin against α-naphthyl isothiocyanate (ANIT)-induced acute cholestasis are associated with the attenuation of oxidative stress ( 11 , 12 ).…”

Melatonin and circadian rhythms in liver diseases: Functional roles and potential therapies

“…α‐naphthylisothiocyanate (ANIT) is a chemical compound that causes cholestasis and liver damage. ANIT elevated serum ALT and AST levels, and melatonin supplementation (100 mg/kg in drinking water for 12 hours following the ANIT injection) decreased those levels in rats . Valproic acid (VPA) is a mood‐stabilizing agent used for psychiatric disorders, but also causes liver damage.…”

“…ANIT elevated serum ALT and AST levels, and melatonin supplementation (100 mg/kg in drinking water for 12 hours following the ANIT injection) decreased those levels in rats. 74 Valproic acid (VPA) is a mood-stabilizing agent used for psychiatric disorders, but also causes liver damage. VPA elevated expression of proinflammatory cytokines including IL-1β and TNFα as well as hepatocyte apoptosis and melatonin administration (10 mg/kg via gavage, 1 hours prior to VPA treatment for 14 days) inhibited those effects.…”