Assessment of the Effects of Graded Doses of Polyphenolic-Rich Fraction of Garcinia kola Seeds on Pituitary–Testicular Axis of Male Wistar Rats

摘要

This study evaluated the ameliorative and prophylactic effects of 2 different doses of polyphenolic-rich fraction of Garcinia kola (PPRFGk) seeds on the histology and hormones of pituitary–testicular axis of male Wistar rats. Thirty-five male Wistar rats (150-200 g) were divided into 7 groups of 5 rats each. Groups I and II were given distilled water (0.5 mL/day) for 8 days followed by propylene glycol (0.2 mL/d) and 600 mg/kg of PPRFGk, respectively, for 21 days. Group III received sodium arsenate (8 days), left untreated for 21 days. Groups IV and V received sodium arsenate (20 mg/kg) for 8 days followed by PPRFGk (300 and 600 mg/kg, respectively) for 21 days. Groups VI and VII received PPRFGk (300 and 600 mg/kg, respectively) for 21 days followed by sodium arsenate (20 mg/kg) for 8 days. Rats were killed by cervical dislocation 24 hours after the last dose and their blood collected through cardiac puncture. Blood sera were assayed for the levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone using immunoassay techniques. Histology of the pituitary gland and testes was carried out. A significant reduction was observed in the concentration of FSH in groups IV, V, VI, and VII in comparison with groups I and II. The concentrations of both LH and testosterone showed significant decreases in groups IV, V, VI, and VII in comparison with group I. Group III presented with the lowest serum hormonal concentrations. Photomicrographs of the pituitary gland revealed greatly reduced basophils in group III and mildly reduced basophils in groups IV, VI, and VII in comparison with groups I and II. Group V revealed hypercellularized and distorted basophils. Photomicrographs of the testes showed detachment of the seminiferous tubules from the basement membrane and disruption of the interstitial space which was worse in group III, moderate in groups V and VI, and mild in group VII. In conclusion, PPRFGk effected a dose-dependent reversal and prevention of the perturbations caused by arsenate in rats.