The possible toxic effect of different doses of Nigella sativa oil on the histological structure of the liver and renal cortex of adult male albino rats

Background:Nigella sativa seeds are commonly known as black seed or black cumin. It has been used for thousands of years as a spice and food preservative and also as a protective and curative remedy for numerous disorders. Aim of the work:Our research aimed to study the possible toxic effect of different doses of N. sativa oil on the liver and kidney. Materials and methods:Twenty-one adult male albino rats were used and divided equally into three groups. The first group was the control group. The second and third groups received the oil in two gradually increasing doses of 15 and 25ml/kg, respectively, for 1 month. The animals were then sacrificed and samples of liver and kidney were taken and prepared for histological examination. Results:In the kidney of group II there was epithelial shedding and necrosis of some cells of the proximal and distal convoluted tubules, but there was no effect on renal glomeruli. In contrast, in group III there was glomerular injury in the form of degeneration of the tuft of capillaries, ill-defined basement membrane, and destruction of endothelial cells, in addition to tubular necrosis. In group II there was minimal effect on the liver in the form of perivascular cellular infiltration; in group III was seen a markedly vacuolated foamy cytoplasm of hepatocytes, with dilated sinusoids and perivascular cellular infiltration. Conclusion:In conclusion, large doses of N. sativa oil have toxic effects on the histological structure of the kidney and to a lesser degree on the liver. Therefore, Nigella oil should be used in proper doses, and further studies on the effect of large doses of oil are recommended.