Glycaemic Control of Aqueous Leaf Extract of <I>Leptadenia hastata</I> and Caffeic Acid in a Fructose-Streptozotocin-Induced Type 2 Diabetic Wistar Rats

Abstract

Type 2 diabetes mellitus (T2DM) is a fast growing health concern, globally affecting 11.1% of the adult population and projected to impact up to 853 million people by 2050. It is characterised by glucose dysregulation, oxidative stress, and inflammation. Despite extensive research, current treatments often carry adverse effects and do not adequately target the oxidative-inflammation component. Leptadenia hastata has been shown to have antioxidant, anti-inflammatory, and antihyperlipidaemic properties, but has not been previously evaluated in validated T2DM models, nor has its efficacy directly compared to that of its primary phenolic compound, caffeic acid (CAFA). The aim of this study was to assess the antidiabetic efficacy of aqueous leaf extract of L. hastata (AELH) and CAFA in a fructose-streptozotocin (STZ)-induced T2DM rat model. Thirty-six male Wistar rats were allocated into six groups (n=6). T2DM was induced by 10% fructose solution for 6 weeks, followed by single dose intraperitoneal STZ injection (35 mg/kg). Diabetic rats were administered AELH (500 mg/kg), CAFA (50 mg/kg), or metformin (METF: 100 mg/kg) for eight weeks. Both AELH and CAFA significantly reduced hyperglycaemia, insulin resistance, dyslipidaemia, and inflammation (p<0.05). Additionally, they significantly increased adiponectin and glucagon-like peptide levels, as well as superoxide dismutase activity (p<0.05), indicating antioxidant activity. The AELH and CAFA effectively mitigated key metabolic disturbances in T2DM, demonstrating efficacy comparable to METF. These findings support AELH and CAFA as promising phytotherapeutic agents for the management of T2DM and its complications.