Protective effect of Aplysin on hepatic injury in ethanol-treated rats

Abstract

This study evaluated the protective effects of Aplysin against ethanol-induced hepatic injury in rats and analyzed the associated mechanisms. Rats were administered orally with ethanol 8-12 ml/kg bw excluding the rats in the control group at 1h after rats were administered by gavage doses of Aplysin (50, 100, and 150 mg/kg bw) every day. After 6 weeks, rats were sacrificed, and liver injury was evaluated by biochemical and pathological examination. Hepatocyte apoptosis was analyzed by annexin V-FITC/PI staining. Ethanol metabolic enzymes, oxidative stress, mitochondrial function, and Bcl-2, Bax, cytochrome c and cleaved caspase-3 expressions were evaluated by western blot analysis. These results demonstrated that Aplysin exhibited a significant hepatoprotective effect. In the ethanol-treated group, cytochrome P4502E1 and alcohol dehydrogenase were increased significantly in liver tissue. Moreover, Aplysin not only significantly reversed the ratio of NAD(+)/NADH and mitochondrial glutathione depletion, but also reversed the decreased activity of mitochondrial respiratory chain complexes I, III and IV. Overexpression of cytoplasmic cytochrome c and caspase-3 activation was suppressed by Aplysin. These results suggest that Aplysin alleviates hepatocyte apoptosis by modulating the ethanol-metabolizing pathway, attenuating oxidative stress, ameliorating mitochondrial function, inhibiting mitochondrial damage-mediated apoptosis, which ultimately prevent and repair alcoholic liver injury.

Keywords: Aplysin; Apoptosis; CAT; CYP2E1; Cyt c; Cytochrome c; GSH; GSH-PX; MRC I, III and IV; Mitochondrial respiratory chain complexes I, III and IV; Mitochondrion; NAD(+); NADH; Oxidative stress; SOD2; catalase; cytochrome P4502E1; cytochrome c; glutathione; glutathione peroxidase; manganese superoxide dismutase; nicotinamide-adenine dinucleotide; reduced form of nicotinamide-adenine dinucleotide.