Effect of eurycoma longifolia on the testosterone level in adult male rats

Background: aqueous extract of the roots of Eurycoma longifolia (EL) have long been used as an enhancer of male sexual performance. However, data from studies in both human males and experimental male animals on the blood testosterone level in those given the EL extract orally were at best insufficiently conclusive. Methodology: sixty-four middle age healthy male rats were acclimatized, then randomized into six treated groups and control. The first three treated groups received orally, low (50mg/kg bw), medium (100mg/kg bw) and high doses (200mg/kg bw) of the EL extract for 15 only. The other 3 treated groups continued receiving treatment for 30 days. By the end of each of the study periods, blood samples were collected and the animals were euthanized, dissected, testicles obtained,weighed, and processed for histological examination. Results: The average relative testicular weight in the high and medium dose treated animals was higher than that in the low dose and control groups. Rats which received medium and high oral doses of EL water extract showed increase of spermatogenesis, mature spermatozoa, Sertoli and Leydig cells. The serum testosterone levels were higher among animals that received the medium and high doses for 15days and 30days. Conclusion: The aqueous extract of EL at the medium and high lebel doses demonstrated similar enhancing effect on serum testosterone levels and testicular spermatogenesis. Our findings suggest that the optimal measured effects of EL treatment in adult male rats is the medium dose of 100mg/kg BW given for 15 or 30 days