Antidiabetic, Antioxidant, Anti-Inflammatory, and Organ-Protective Effects of Kura Mynis Polyherbal Formulation: In Vitro, Cellular, and In Vivo Evaluation in Streptozotocin-Induced Diabetic Rats

Background: Diabetes mellitus is a chronic metabolic disorder associated with persistent hyperglycemia, oxidative stress, inflammation, and progressive organ damage. The present study investigated the antidiabetic potential of Kura Mynis (KM), a novel polyherbal formulation containing multiple bioactive plant extracts with reported glucose-lowering, antioxidant, and anti-inflammatory properties. Methods: The antidiabetic activity of KM was evaluated using in vitro α-amylase, α-glucosidase, xanthine oxidase, anti-inflammatory, and DPPH radical scavenging assays. Insulinotropic activity was assessed in MIN6 pancreatic β-cells, while cytotoxicity was determined using the MTT assay in HepG2 cells. In vivo efficacy was evaluated in streptozotocin-induced diabetic Wistar rats treated orally with KM (2055 and 4102 mg/kg) for 21 days. Blood glucose levels, body weight, lipid profile, liver function markers, and histopathological changes in pancreatic, hepatic, and renal tissues were assessed. Results: KM exhibited concentration-dependent inhibition of α-amylase (85%), α-glucosidase (58%), and xanthine oxidase (67%) at 100 µg/mL. Significant anti-inflammatory activity (44%) and potent antioxidant activity were observed, with 94.11% DPPH radical scavenging and an IC₅₀ value of 86.93 µg/mL. KM enhanced insulin secretion in MIN6 cells by approximately 2.6-fold at 100 µg/mL without inducing cytotoxicity. In diabetic rats, KM significantly reduced fasting and postprandial blood glucose levels, improved body weight, and produced group-dependent modulation of serum transaminase and lipid parameters. Pancreatic, hepatic and renal histoarchitecture were substantially restored in a dose-dependent manner. Conclusion: KM exerts significant antidiabetic effects through multiple mechanisms, including enzyme inhibition, antioxidant and anti-inflammatory activities, enhancement of insulin secretion, and histological preservation of pancreatic, hepatic and renal tissue. Effects on serum transaminases and lipids were modulatory and were not uniform across treatment groups. These findings support KM as a promising polyherbal candidate for diabetes management and its associated complications.