Aqueous Methanol Extract of Gongronema latifolium Leaf Protects Against Dibutyl Phthalate-Induced Alterations in Semen Parameters in Rat

Abstract

Male infertility in humans and wildlife has been linked to environmental, lifestyle and dietary factors. Dibutyl phthalate (DBP), a plasticizer, is a ubiquitous environmental toxicant known to adversely affect male reproduction. This study investigated the mechanism of toxicity of DBP on the testes and evaluated the ameliorative potential of aqueous-methanol extract of Gongronema latifolium (GLE) leaf on DBP-induced testicular toxicity in male rats. Twenty-eight (28) male Wistar rats (180 ± 20 g) were randomly divided into four experimental groups of 7 rats each; Group 1 was the control, Group 2 was treated with DBP only (500 mg/kgbw), Groups 3and 4 received DBP (500 mg kg-1 body wt) and GLE (400 and 500 mg/kgbw. respectively). DBP and GLE were administered daily by gavage for 14 days. The results revealed that DBP significantly (p < 0.05) increased superoxide dismutase (SOD) with a concomitant increase in lipid peroxidation in the testes. It also significantly increased the number of deformed sperm cells, testicular cholesterol, plasma testosterone and T/LH ratio while, sperm count, sperm motility and plasma LH were significantly (p < 0.05) reduced relative to the control. Histopathological examination of the testes revealed DBP-induced distortion in testes architecture with marked degeneration of the seminiferous tubules and Leydig cells. Vascular damage, ulceration, and fibrosis of anterior pituitary-testicular artery and Leydig cell hyperplasia were also observed. Treatment with aqueous-methanol extract of Gongronema latifolium (GLE) leaf provided significant protection, with the 400 mg/kg body weight treatment being the most effective dose in this study.