The Study of the Protective Effect of Black Cumin (Nigella sativa linn.) Ethanolic Extract Against Rifampin-induced Hepatotoxicity in Rats

Anti-tuberculosis drug, rifampin, is toxic for liver. This study was conducted to determine the preventive effects of black cumin (Nigella sativa Linn.) extract against rifampin-induced hepatotoxicity in rats. In this experimental study, 40 male Wistar rats were randomly divided into 4 equal groups: 1- control group, 2- toxic drug group, 3- positive control group, and 4- extract treatment group, respectively received normal saline, rifampin (at a dose of 500mg/kg), silymarin (at a sose of 50mg/kg) plus rifampin, and ethanolic extract of black cumin (250mg/kg) plus rifampin, daily through gavage for one month. Finally, serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, bilirubin, albumin, and protein, were assessed. Malondialdehyde level and activities of liver superoxide dismutase, catalase, glutathione peroxidise, and glutathione reductase, were measured. Histopathological analysis was performed to evaluate the various degrees of liver injury. The groups were compaired using statistical tests of one-way ANOVA and Tukey, s post-test. Silymarin and black cumin extract significantly decreased the serum levels of liver function biomarkers, bilirubin, and malondialdehyde and increased the serum levels of albumin and protein and the levels of liver antioxidant enzymes in the rats treated with rifampin (p<0.01). Histopathologically, silymarin and black cumin extract improved the rifampin-induced hepatic injury. Histopathological results were consistent with biochemical findings. Accordind to the results of this study, black cumin extract with antioxidant properties, protects liver tissue against rifampin-induced oxidative damage.