Crude Extract and Phenol-Rich Fractions from Vernonia amygdalina Leaves Ameliorates Streptozotocin-Induced Type 1 Diabetes in Rats by Mitigating Hepatic Injury, Dyslipidemia, and Production of Oxido-Inflammatory Markers.

Diabetes mellitus (DM) is a major disorder contributing to human mortality and morbidity globally. The use of medicinal plants in the management of diabetes is gaining global popularity due to their accessibility and cost-effectiveness. In this study, we evaluated the ameliorative potential of Vernonia amygdalina leaves crude extract (CE), free phenol (FP), and bound phenol (BP) fractions (50 mg/kg body weight) in a rat model of streptozotocin (STZ)-induced type 1 diabetes (T1DM). The effects of these treatments for 28 days on glucose, insulin, glycated hemoglobin, hepatic injury indices, and lipid profile were assessed in the serum. Furthermore, redox biomarkers (liver) and inflammatory mediators (serum and liver) were analyzed. Our results indicated that CE, FP, and BP fractions of Vernonia amygdalina inhibited the deleterious effects of T1DM by attenuating hyperglycaemia, insulin deficiency, hepatic injury, and dyslipidemia. Also, CE, FP, and BP fractions differentially improved antioxidant enzymes activity and reduced oxidative and inflammatory markers production. Specifically, CE showed superior effects compared with FP, BP, and metformin across multiple biomarkers, including glycated hemoglobin, α-amylase, α-glucosidase, hepatic glycogen, total cholesterol, LDL-cholesterol, protein carbonyl, SOD, IL-1β, and IL-10. The antidiabetic effects produced by CE, FP, and BP fractions of Vernonia amygdalina may be ascribed to the presence of different bioactive phytochemicals as revealed by HPLC analysis. Overall, our data would suggest a potential therapeutic role for Vernonia amygdalina leaves extracts in addressing hepatic complications due to T1DM.