Aim of the work: The effect of diabetes on the liver is associated with histological changes. The aim of the present study was to evaluate the histological changes following administration of nigella sativa (NS) in the streptozotocin (STZ) induced diabetes mellitus in rats.
Materials and Methods: Thirty six male white rats (n=36), weighing (180–230 g) were taken for this study. The animals were divided into 3 groups: 1- Normal control group. 2- Diabetic group. 3- Diabetic group treated by Nigella Sativa (N.S) oil. Diabetes was induced in the experimental rats via intraperitoneal injection of streptozotocin (45 mg/kg body weight) in a single dose. The fasting blood glucose was estimated, 5ml\kg of body weight of N. sativa oil was given orally for three weeks. After an overnight fast, the animals were sacrificed. The livers were identified, weighed and observed for any gross appearance and color changes and tissues were preserved for histopathological studies using hematoxylin & eosin (H&E) and periodic acid Schiff (PAS) stains.
Results: In streptozotocin treated animals, the body weight was significantly decreased compared to normal rats, while treating diabetic rats with N. sativa oil showed significant increases in the body weight. Administration of nigella sativa oil to diabetic rats resulted in a
significant decrease in blood glucose after three weeks compared to untreated diabetic rats. In untreated diabetic group, there was a significant decrease in the liver glycogen. Light microscopic examination of the liver of diabetic rats revealed profound histological changes. Nigella sativa consumption could reverse most of these histological and biochemical changes in the liver of the diabetic group owing to its hypoglycemic and antioxidant effect.
Conclusion: The Nigella Sativa due to its antioxidant role may be helpful in reversing the changes in the liver in diabetes mellitus.