Molecular Approach to Identify Anti-inflammatory Potential of Stevioside in HFD-induced Type 2 Diabetic Rats: Evidence From in Vivo Study

Abstract

Stevioside is a natural sweetener derived from the leaves of the Stevia rebaudiana plant. It has gained popularity as a sugar substitute due to its intense sweetness without adding calories or affecting blood sugar levels, making it a suitable option for people with diabetes or those looking to reduce their sugar intake. Studies have shown that stevioside has glucose lowering effects. Previous studies have shown that it has significant role in skeletal muscle but its role on expression of inflammatory signaling molecules in adipose tissue against high diet and sucrose-induced type-2 diabetes in experimental rats is yet to be done. The current research was undertaken to investigate if stevioside could also exert its antidiabetic effects by circumventing adipocyte induced inflammation, a key driving factor for insulin resistance in obese individuals. Effective dose of stevioside (20 mg/kg b.wt) was administered orally for 45 days to high fat diet and sucrose induced type-2 diabetic rats. Interestingly, stevioside treatment restores the elevated serum levels of proinflammatory cytokines including tumor necrosis factor-α (TNF-α) and sterol regulatory element binding protein-1c (SREBP-1c) and enhances Peroxisome Proliferator–activated receptor-γ (PPAR-γ) in adipocytes of diabetic rats. The gene expression of IR, GLUT4 and PPAR-γ mRNA were also significantly activated in stevioside treated groups but reduced IL-1 beta, IlL-6, IKKB, TNF-alpha and NFkB mRNA expression in diabetic adipose tissue. More importantly, stevioside acts very effectively as metformin to circumvent inflammation and insulin resistance in diabetic rats. Our results clearly show that stevioside inhibits obesity induced insulin resistance by ameliorating the inflammatory events and upregulating insulin signalling molecules. Keywords: Stevioside, HFD-T2DM, pro inflammation, insulin signalling; adipose tissue, obesity; signaling pathways; Therapautics.