Effects of hydromethanolic extract of saffron (Crocus sativus) on serum glucose, insulin and cholesterol levels in healthy male rats

Abstract

Saffron and its constituents are reported to have a wide range of biological activities. To determine the hypoglycemic effect of hydromethanolic extract of saffron, which has rarely been dealt with in previous studies and hypolipidemic effect of saffron extract, we investigated the effects of hydromethanolic extract of saffron on healthy male rats. The present study also aimed at evaluating the effects of saffron extract on insulin secretory function of pancreatic beta-cells. In this study, healthy male rats (n = 30) were divided into 3 groups of ten: The test group (saffron group), the sham group (physiologic serum group) and the normal group. The test group received 50 mg/kg saffron extract through intraperitonal injection. The sham group was also intraperitoneally injected by 50 mg/kg of physiologic serum solvent for 2 weeks. Daily injection was repeated at 10 am. Blood samples were obtained from retro-orbital sinus before administration and on the 7th and 14th days of administration. The serum glucose and cholesterol levels were measured by the enzymatic method and insulin levels were measured using insulin kit by ELISA method. The results showed that hydromethanolic extract of saffron on the 7th day of administration, significantly decreased serum glucose in saffron group without having any effects on serum cholesterol and insulin levels. On the 14th day of administration, we found significant decrease of serum glucose and cholesterol levels in saffron group. In addition, after 2 weeks, serum insulin in test group significantly increased compared to the sham and normal groups. No changes were observed on serum glucose, cholesterol, and insulin levels in sham and normal groups on the 7th and 14th days of administration. These results suggest that saffron extract has hypoglycemic and hypolipidemic effects on healthy male rats. Moreover, saffron extract could increase their insulin secretion from pancreatic beta-cells. Therefore, it should be considered in future therapeutic researches.