Histopathological study of the protective effects of ethanolic extract of Crocus sativus L. (Saffron) stigma on hepatic and renal tissue changes in alloxanized diabetic rats

Diabetes mellitus is a metabolic disorder affecting mankind and its incidence is considered to be high all over the world. Hepatic and renal insufficiencies are identified as the most important causes of death in this disease. A multitude of herbs has been described for the treatment of diabetics throughout the world. The aim of the present study was to assess the protective effects of ethanolic saffron stigma extract (Crocus sativus L.) on early hepatic and renal injuries in alloxan-induced diabetic rats.  For this purpose, 72 male wistar rats were randomly assigned to six different groups of 12 rats each, including healthy control rats, healthy control rats receiving ethanolic saffron extract, mild diabetic (MD) rats, mild diabetic rats receiving ethanolic saffron extract, severely diabetic (SD) rats and severely diabetic rats receiving ethanolic saffron extract. The most effective dose of the extract in reducing blood glucose (40 mg/kg), dissolved in normal saline solution (10 ml/kg) was administered intraperitoneally to treatment groups receiving the extract for 30 consecutive days. Control groups received normal saline solution in the same manner. Four hours after the last extract injections, all rats were euthanized simultaneously by cervical dislocation. Tissue specimens were fixed in 10% buffered formalin and 5 micron thick sections were prepared using routine hitopathological techniques. Histopathology of the liver and kidney in diabetic rats showed a spectrum of changes including periportal degeneration, membranoproliferative glomerulitis, enlargement of lining cells of tubules, lymphocytic infiltration, hyperemia and hemorrhage. These injuries were more prominent in SD rats. The histopathological appearance of liver and kidneys in ethanolic extract treated diabetic rats was near normal. The findings of the present study indicate that ethanolic extract of Crocus sativus L. stigma has protective effects on early diabetic nephropathy and hepatopathy in experimentally induced diabetes. Therefore, ethanolic extract of Crocus sativus L. stigma is recommended for prevention of early renal and hepatic injuries in diabetes mellitus, after randomized clinical trials.