The investigation of the antidiabetic effect of Rhaponticoides iconiensis (Tülüşah) extract in Type 2 diabetic rats

Diabetes Mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia resulting from impaired insulin secretion, insulin action, or both. The aging population, urbanization, and changing lifestyles are rapidly increasing the diabetes epidemic along with other chronic diseases. With the rapidly increasing incidence of diabetes, the need to protect vital organs from diabetic damage and treat it, especially considering that Type 2 diabetes accounts for approximately 90% of total diabetes cases, is of great importance. Compounds with antioxidant activity can have positive effects in the treatment of diabetes, which is a disease characterized by oxidative stress. In this study, the usability of Rhaponticoides iconiensis as a supplement to drugs that are thought to have side effects, in terms of its antioxidant effect and antidiabetic effect potential due to the phenolic components it contains, was investigated in the treatment of rats with Type 2 Diabetes caused by high-fat diet and STZ. Antidiabetic contents of phytochemical compounds contained in various extracts obtained from Rhaponticoides iconiensis (RI) roots, leaves and flowers have been demonstrated in studies, but their antidiabetic effects have not been evaluated. Therefore, it was planned to evaluate the effect of RI leaf extract on previously established antioxidant, α-amylase, and α-glucosidase activities under in vivo conditions using rats in a proposed thesis project. The results obtained from oral administration of RI extract in rats showed that its efficacy as a supplement in the treatment of Type 2 Diabetes Mellitus (T2DM) and in the prevention of complications caused by diabetes by reducing hyperglycemia, dyslipidemia, chronic inflammation and oxidative stress was investigated histopathologically using biochemical markers TAS, TOS, TNFα, IL-1β, IL-6, WNT5A, SFRP5 and Anti-Insulin, Anti-Caspase 3, Anti-TGFβ1 antibody labeling and Hematoxylin & Eosin (H&E) staining. The antidiabetic activity of RI extract was investigated in comparison with Acarbose (Glukobay®) used in the treatment. 46 rats were divided into 6 groups as Control, DM, DM + 30 mg/kg Acarbose, DM + 100 mg/kg RI extract (RI1), DM + 200 mg/kg RI extract (RI2), DM + 300 mg/kg RI extract (RI3). Experimental diabetes, high fat diet (HFD) and T2DM were induced by intraperitoneal (i.p.) injection of two doses of streptozotocin one week apart. All doses of RI extract and Acarbose were administered via gastric gavage for 28 days. As a result, demonstrated in this study that the extract of RI, rich in bioactive components obtained with methanol can supplement existing treatments by having an acarbose-like antidiabetic effect on rats with T2DM. Key Words: Type 2 Diabetes, Rhaponticoides iconiensis, Inflammation, Antioxidant, Oxidative stress