Effect of Chronic Exposure to Aqueous Extract of Dialium guineense (Velvet Tamarind) Stem Bark on Cardiovascular Disease Risk Factors of Diabetic Wistar

Abstract

Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide, with its prevalence and associated complications continuing to rise globally with its increasing health risk factors and financial costs, while existing conventional drugs are becoming less and less effective. In the search for a sustainable and affordable alternative green drug, this paper sought to evaluate the effect of chronic exposure to aqueous extract of Dialium guineense (AEDG) (Velvet Tamarind) stem bark on cardiovascular disease risk factors in streptozotocin (STZ)-induced diabetic rats. Twenty male Wistar albino rats weighing 150 – 180 g (165 ± 15 g) were randomly assigned to four groups (n = 5): control, diabetic, metformin-treated, and extract-treated groups. Diabetes mellitus was induced in all groups except the control by a single intraperitoneal injection of 50 mg/kg body weight (bwt) STZ. Following confirmation of diabetes mellitus, rats were treated orally with either AEDG (1000 mg/kg bwt) or metformin (50 mg/kg bwt) for 35 days. Biochemical assessments were conducted weekly throughout the experimental period. The results revealed significant and time-dependent reductions in traditional lipid profile parameters, including total cholesterol (TC), triacylglycerol (TG), very-low-density lipoprotein cholesterol (VLDL-C), and low-density lipoprotein cholesterol (LDL-C), in the extract- and metformin-treated groups compared with untreated diabetic rats (p < 0.05). Similarly, cardiovascular disease risk indices, namely Castelli Risk Index-I (CRI-I), Castelli Risk Index-II (CRI-II), Atherogenic Index of Plasma (AIP), Atherogenic Coefficient (AC), and Atherogenic Combined Index (ACI), were significantly decreased following treatment (p < 0.05). Conversely, total protein concentration, high-density lipoprotein cholesterol (HDL-C), cardiovascular risk ratio (CRR) and protective ratio (PR) exhibited significant improvements relative to the diabetic group. These findings suggest that aqueous stem bark extract of Dialium guineense possesses potent antihyperlipidemic and cardioprotective properties, and may effectively ameliorate diabetes-induced dyslipidemia and associated cardiovascular complications.