Aphrodisiac and androgenic effects of the aqueous extract of the roots of Vepris afzelii on cyproterone acetate-induced hypogonadism in rat

Abstract

This work aimed to evaluate the effects of the aqueous extract of Vepris afzelii roots on a rat model of hypogonadism. Phytochemical screening and acute toxicity of the extract were performed using different procedures. Hypogonadism was induced orally in adult Wistar rats using cyproterone acetate (30 mg/kg) for ten days. Besides six normal rats (10 ml/kg of distilled water, normal control), 30 hypogonadal rats were subdivided into five groups of six animals each, receiving for 14 days: distilled water (10 ml/kg, hypogonadal control), testosterone (4 mg/kg/3days) and the extract of V. afzelii (100, 200 and 400 mg/kg). Sexual behavior, sperm parameters, testes function and structure were assessed. Compared to the normal controls, significant (p = 0.0000) increases in mount (24 ± 0.94 seconds vs. 1200 ± 00 seconds) and intromission (49.16 ± 10.85 seconds vs. 1200 ± 00 seconds) latencies, and post-ejaculatory interval (381.72 ± 37.55 seconds vs. 1200 ± 00 seconds) were observed in all groups receiving cyproterone acetate on day 0. Total inhibitions of mounts (63.50 ± 8.91 vs. 00 ± 00), intromissions (36.66 ± 3.51 vs. 00 ± 00) (p = 0.0000), ejaculations (2.83 ± 00 vs. 00 ± 00, p = 0.0002) frequencies and mean copulatory interval (627.30 ± 81.80 vs. 00 ± 00, p = 0.0000) were also observed in these groups. Moreover, decreases in daily sperm production (2.65 ± 0.19 vs. 1.17 ± 0.08, p = 0.0498), percentage of sperm mobility (78.64 ± 8.41 vs. 10.12 ± 2.32), serum testosterone level (8.39 ± 0.63 ng/dl vs. 1.68 ± 0.19 ng/dl), diameter of seminiferous tubules (111.97 ± 0.51 µm vs. 94.51 ± 0.57 µm) and height of germinal epithelium (46.58 ± 0.34 µm vs. 33.74 ± 0.66 µm) (p = 0.0000) associated with increases in sperm transit (3.13 ± 0.45 vs. 11.07 ± 1.45, p = 0.0000) were also observed in these groups. Interestingly, compared to hypogonadal control and day 0, the administration of V. afzelii extract induced significant (p = 0.0000) improvements in all these altered parameters with 400 mg/kg being the most active dose. These results, attributed to saponins, flavonoids, polyphenols and triterpenes detected in this plant's extract confirm its traditional usage and could be useful for the management of patients suffering from hypogonadism.