protective effect of nigella sativa oil and the derived thymoquinone and nigellone against thioacetamide induced liver fibrosis in rats

ABSTRACT

The present study examined the effect of oral administration of Nigella saliva oil [NSO], thymoquinone [TQ], the main active principle of the volatile oil of NSO and nigellone [NG], the less toxic carbonyl polymer of TQ, on progress of thioacetamide [TAA] -induced liver fibrosis in rats. Sixty male albino rats weighing 150-200 g/rat were classified into 6 groups as follows group I, [saline-control], group II [TAA-induced liver injury], group III [NSO-treated], group IV [TQ-treated], group V [NG-treated] and group VI [propylene glycol - treated]. NSO, TQ, NG and propylene glycol were given daily orally for 6 weeks starting with TAA administration. Propylene glycol was the vehicle of TQ and NG. TAA-injury [group II] caused a significant rise in the portal pressure and serum concentrations of tumor necrosis factor -alpha, transforming growth factor - beta[1] and malondialdehyde. Moreover, liver function tests [serum aspartate and alanine aminotransferases, alkaline phosphatase and gamma-glutamyl transferase activities and serum albumin concentration] were significantly impaired in group II as compared to group I. Liver tissues obtained from rats treated by TAA had higher hydroxyproline and lower reduced glutathione contents as compared to saline-control [group I]. Administration NSO, TQ or NG caused significant and similar protective effects against all TAA-induced haemodynamic and biochemical impairments. This study suggests that NSO, TQ and NG are significantly and probably equally effective against TAA-induced liver injury and fibrosis. Inhibition of synthesis and/or release of TNF-alpha and TGF-beta[1] as well as inhibition of tissue oxidative stress may be of particular importance