Gymnemagenin a Promising Drug Candidate for Management of Hyperglycemia: In-Vitro and In-Vivo Study

Javed Ahamad¹, Saima Amin², Kamran J Naquvi¹, Showkat R Mir^3*

Study of Gymnema sylvestre plant for the treatment and management of diabetes.

Abstract

Background: Diabetes mellitus is a chronic metabolic disorder resulting from absolute or relative impairments in β-cell functions, insulin resistance, or both and has been exceptionally increasing worldwide. Gymnema sylvestre is an important traditional plant used for the treatment and management of diabetes. Gymnemagenin is an aglycone part of gymnemic acids which is a bioactive component of G. sylvestre. The objective of the present study was to undertake in-vitro and in-vivo studies to generate a stronger biochemical rationale for the management of diabetes mellitus. Results: The result of the preliminary in-vitro study of gymnemagenin suggested further evaluation of the inhibition of key enzymes related to carbohydrate metabolism. Gymnemagenin showed strong α-amylase (IC₅₀ 1.17±0.02 mg/mL) and strong α-glucosidase (IC₅₀ 2.04±0.17mg/mL) inhibitory activity. The positive in-vitro enzyme inhibition tests paved the way for confirmatory in-vivo studies. The in-vivo studies demonstrated that gymnemagenin (20 mg/kg, b.w.) given orally significantly (P<0.01) reduced area under curve (AUC) in mice when challenged with oral administration of starch and sucrose separately. The reduction in AUC by gymnemagenin was comparable to that of acarbose (10 mg/kg, b.w., p.o.). Conclusion: The research findings clearly supported the traditional use of G. sylvestre in the treatment of diabetes mellitus.

Keywords: Gymnema sylvestre, gymnemagenin, diabetes mellitus, α-amylase, α-glucosidase. 

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