effect of nigella sativa on ischemia-reperfusion induced rat kidney damage

objective(s):there are a few previously reported studies about the effect of nigella sativa oil on renal ischemia-reperfusion injury (iri). the aim of the present study was to test the hypothesis whether pre- or post-treatment with n. sativa hydroalcoholic extract (nse) would reduce tissue injury and oxidative damages in a clinically relevant rat model of renal iri.    materials and methods: iri was induced by clamping of bilateral renal arteries for 40 min fallowed by reperfusion for 180 min. nse was prepared in a soxhlet extractor and administrated with doses of 150 mg/kg or 300 mg/kg at 1 hr before ischemia induction (p-150 and 300) or at the beginning of reperfusion phase (t-150 and 300), via jugular catheter intravenously. the kidneys were then removed and subjected to biochemical analysis, comet assay or histopathological examination. results: the kidneys of untreated iri rats had a higher histopathological score (p<0.001), while in p-150, as well as t-150 and t-300 groups tubular lesions significantly decreased (p<0.001). pre- and post-treatment with nse also resulted in a significant decrease in malondialdehyde (mda) level (p<0.001) and dna damage (p<0.001) that were increased by renal i/r injury. nse treatment also significantly restore (p<0.01) the decrease in renal thiol content caused by iri. conclusion: the present study shows n. sativa extract has marked protective action against renal iri, which may be partly due to its antioxidant effects.