ABSTRACT

The aims ofthis study were to validate some protocols used for experimental induction of benign prostate hyperplasia (BPH) and evaluate to the prophylactic and chemotherapeutic effects of Vernonia amygdalina methanol leaf extract (VAMLE) on reproductive indices, oxidative stress and BPH markers in experimentally induced-BPH male Wistar rats. The study was divided into induction (I), prophylactic (II) and chemotherapeutic (III) studies. In the induction study, fifty-four male rats aged 11-12 weeks old, were randomly selected and divided into six groups (I-VI) ofnine rats each. Group I served as the normal control. Bilateral orchiectomy was carried out on rats in groups, TV and V but not in I, II and III, while group VI served as the sham castrated (incision only) group. BPH was induced in the different groups except group I (normal control) and grp VI (sham) by administering either testosterone propionate alone (6mg/kg/ s/c; groups II & IV) or in combination with estadiol valerate (0.6mg/kg/s/c; groups III & V) every other day for 28 days. Three animals from each group were humanely sacrificed on days 14, 21 & 28 to evaluate progressive BPH development using a combination of some established BPH markers. In the prophylactic study, male rats were divided into six groups A-F offive rats each. Apart from group A, BPH was induced in all other groups using testosterone (6 mg/kg s/c) and estradiol (0.6 mg/kg s/c) alternate day for 28 days. Group B was not treated, Groups C, D and E received graded doses 50, 100 and 200 mg/kg of V. amygdalina leaf extracts respectively while F received finasteride (10 mg/kg) concurrently with the induction agents for 28 days, after which they were sacrificed. The treatments and groupings in study III were similar as for study II except that the treatments were administered 3 weeks post BPH induction. Three animals from each group were humanely sacrificed on days 14,21 and 28 post treatment and reproductive/BPH indices were measured to evaluate the progress of BPH management. Data were presented as mean ± SEM, analyzed using ANOVA and means were further separated with Duncan multiple test. The results from study I showed significant (p<0.05) higher rate of induction of BPH with testosterone alone or in combination with estradiol in non-castrated rats right from day-14 post administration with a significant (p<0.05) increase in the relative size of prostate gland, higher Prostatic acid phosphatase and Prostate Specific antigen serum levels compared with the normal rats. Results from study II and III, showed that VAMLE leafextract at lower doses (50 and 100 mg/kg b.w) exhibited better prophylactic and chemotherapeutic activities than the standard (Finasteride) drug in ameliorating adverse effects ofthe BPH in the experimental rats. The reproductive organs histology evidently revealed reduced hyperplasia. Thus, it was concluded that induction with testosterone and estradiol gave the best results. This leaf extract when properly harnessed, could become a better alternative for BPH management. Further studies are hereby recommended to reveal the putative mechanism of action.