Aim: To evaluate the effect of the alcoholic extract of Lepidium meyenii (Maca) on the spermatogenesis in male rats. Methods: In Holtzman rats, Maca alcoholic extract (5 %) was given by oral route at doses of 48 mg/day or 96 mg/day for 7 days, 14 days and 21 days. Testicular function was assessed by measurements of lengths of different stages of seminiferous epithelia and by epididymal sperm count. Results: Ethanolic extract of Maca increased the length of stages IX-XI of seminiferous epithelium at treatment day 7, day 14 and day 21. Progression of spermatogenesis was evident only after day 21 when lengths of stages XII-XIV of seminiferous epithelium were increased; at day 7 and day 14, no important change in spermatogenesis was observed. Epididymal sperm count was increased with 48 mg/day at all times. With 96 mg/day an increase in sperm count was observed at day 7, but it was reduced at day 14 and day 21 of treatment. Serum testosterone levels were not affected. Conclusion: The alcoholic extract of Maca activates onset ant progression of spermatogenesis at 48 mg/day or 96 mg/day in rats.

Lepidium meyenii (Maca) is a perennial plant cultivated in the Andean mountains over 4,000 m altitude. The root traditionally has been used for its fertility-enhancing properties as described in the Spaniard conquest Chronicles of Peru in 1653 [1]. Probably Maca was domesticated in San Blas, Junin, 1300 to 2000 years ago [2]. Recently, it has been demonstrated that aqueous extract of Maca improves spermatogenesis and semen parameters [3, 4]. In the present study, the effect of the alcoholic extract of Maca on spermatogenesis and epididymal sperm count was assessed.

The fat of the dried and powdered roots of Lepidium meyenii (750 g) was removed with soaking in hexane at room temperature (20 ) for 3 days. The residue obtained (14.5 g) was extracted with 1,500 mL absolute ethanol for 72 h at room temperature. The filtrate was concentrated under reduced pressure at 40 with Rotovapor (Bchi, Water bath B-480, Switzerland) and the final dry extract weighed 53.1 g. The dry extract, 2.4 g and 4.8 g, were dissolved separately in 100 mL of 5 % ethanol with resultant solutions of 24 mg/mL (solution A) and 48 mg/mL (solution B).

Data were presented as meanSEM and analyzed using t-test and analysis of variance (one way) when more than two groups were compared. P<0.05 was considered significant.

Treatment with the ethanolic extract of Maca for 7 days resulted in increase of the lengths of stages VII and IX-XI and a relative reduction in stages XIII-XIV and II-III of the seminiferous tubules. At the higher dose of 96 mg/day, a reduction in stage VIII length was also observed (Table 1). After 14 days of treatment, an increase in lengths of stages VII and a relative reduction in stages II-III were observed (Table 2). The length of stage VII was increased at the dose of 48 mg/day, but not at the higher dose. After 21 days of treatment, there was an increase in stage IX-XI and a relative decrease in stage IV-V with both doses (Table 3). Briefly, Maca treatment increased the lengths of stages IX-XI seminiferous tubules at day 7 , day 14 and day 21. Progression of spermatogenesis was observed after 21 days of treatment as the lengths of stages XII-XIV were increased.

Table 1. Seminiferous tubular lengths (cm) of rats (n=6) treated for 7 days. ^bP<0.05; ^cP<0.01, compared with controls.

Table 2. Seminiferous tubular lengths ( cm) of rats (n=6) treated for 14 days. ^bP<0.05; ^cP<0.01, compared with controls.

We have previously demonstrated that treatment with the aqueous extract of Maca for 7 days increased the length of stage VIII seminiferous tubules and the epididymal sperm count and treatment for 14 days increased the lengths of stage IX-XI, but there was no increase in sperm count; at day 21 a promotion of spermatogenesis was observed as the lengths of stages XIII-XIV were increased [3]. A dose-dependent increase in stage VIII was observed with aqueous extract of Maca at day 7 with the highest response at the dose of 666.6 mg/day [Gonzales GF et al Unpublished data ].

Sharon Castillo and Carmen Goez for providing technical support. The study was financially supported by Vicerrectorate of Investigation at the Universidad Peruana Cayetano Heredia.