Levels of Expression of Hsp70 and iNOS and Effect of Artemisia Sieberi (A. herba-alba) on Activity of Hypothalamic-Pituitary-Thyroid (HPT) Axis in Diabetic Rats

Abstract

This work was carried out to evaluate levels of expression of the Heat Shock Protein 70 (Hsp70) and inducible nitric oxide synthase (iNOS) biomarkers in extracts of Artemisia sieberi (A. herba-alba) and their impacts on the activity of hypothalamic-pituitary-thyroid (HPT) axis in diabetic rats. 50 rats were separated into five experimental groups: a normal control group, a positive control group treated with dilute A. herba alba (AHE) oil extract, a diabetic non-treated group, a diabetic group treated with AHA extract, and a diabetic group treated with Metformin. Results: Orally administered 8.1 mg/kg body weight (BW) of dilute AHA oil and 14.2 mg/kg BW of Metformin were administered for 6 weeks. Serum triiodothyronine (T3) levels decreased significantly in diabetic rats and increased significantly in the rats treated with the dilute AHA oil. Furthermore, no significant differences were observed in thyroid gland Hsp70 expression between the diabetic and non-diabetic rats. Metformin and dilute AHA oil treatments significantly increased the expression of Hsp70 in the thyroid gland. The results also demonstrated that diabetes significantly increased the rate of iNOS expression in the thyroid gland. Treatment with Metformin and dilute AHA oil significantly reduced the expression of iNOS in the thyroid gland. These results suggest that dilute AHA oil plays a role in the peripheral regulation of thyroid function and provide empirical evidence that it contributes to the stimulation or improvement of thyroid function.