Antioxidant Properties of Saffron Stigma and Petals: A Potential Therapeutic Approach for Insulin Resistance through an Insulin-Sensitizing Adipocytokine in High-Calorie Diet Rats

BACKGROUND: Oxidative stress and alteration of lipid profile due to obesity and overweight is a major risk factor for atherosclerotic plaque or coronary artery disease. Because of antioxidant and lipid lowering potential of saffron, this study investigated weight alteration, lipid profiles, and insulin resistance index in high-calorie diet rats treated with aqueous extract of saffron stigma and petal. METHODS: Forty Sprague-Dawley male rats were randomly divided into 8 groups including healthy control, high-fat diet control, nicotinic acid treated, Anethum graveolens treated, and saffron stigma and petal treated groups. Rats received a high-calorie diet for 16 weeks. For treatment, aqueous extract of saffron stigma (40 and 80 mg/kg) and petal (50 and 100 mg/kg) was used once daily for 4 weeks. Afterward, lipid profile, oxidative stress status, and insulin and adiponectin levels were measured using desired kits. RESULTS: There was a significant decrease in the mean weight of the groups receiving saffron stigma and petal compared to control group (P < 0.05). The increased level of insulin hormone in obese group was improved in treated groups especially in the case of saffron stigma. Also, the decreased level of adiponectin was recovered in treated groups. An improvement was seen in oxidative stress markers and lipid profiles in treated groups compared to obesity pair. CONCLUSIONS: In this study, a remarkable antioxidant and lipid lowering potential was detected for saffron stigma, which could improve insulin resistance in obese rats. Therapeutic and protective effect of saffron is mainly related to its richness in phenolic compounds. Saffron stigma compared with petal had more notable effect, which could and should be mentioned in pharmaceutical studies.