Objective: To evaluate the effect of L-carnitine (LC) on low sperm acrosin activity in infertile man.
Methods: A total of 240 male infertility patients with low sperm acrosin activity were randomly assigned to an LC group (n = 180) and a control group (n = 60) to be treated with LC (1g, tid) and vitamin E (VE) capsules (100 mg, tid) respectively, both for 3 months. Based on the results of routine semen analysis, the patients in the experimental group were further divided into oligozoospermia, asthenozoospermia and normozoospermia subgroups. Semen parameters and sperm acrosin activity were examined before and after treatment.
Results: Totally, 220 of the patients completed the treatment and follow-up, 163 in the LC medication and 57 in the VE control group. Compared with the baseline, the percentage of progressively motile sperm (PMS) was significantly increased in the LC group after 3 months of treatment ([32.58 ± 1.13]% vs [36.35 ± 1.26]%, P < 0.05), and so was sperm acrosin activity ([37.05±0.66] vs [58.61±1.93] μIU/106 sperm, P < 0.01). Sperm concentration, PMS and sperm acrosin activity were also improved in the VE control group after treatment, but with no statistically significant difference (P > 0.05). In comparison with pretreatment, remarkable increases were observed after LC medication in sperm concentration in the oligozoospermia subgroup ([11.27 ± 0.73] vs [21.82 ± 4.21] ×10⁶/ml, P < 0.01) and PMS in the asthenozoospermia patients ([20.61 ± 0.85]% vs [29.81 ± 1.88]%, P < 0.01). And sperm acrosin activity was even higher after treatment in the asthenozoospermia than in the oligozoospermia and normozoospermia subgroups ([60.85 ± 3.04] vs [56.32 ± 2.86] and [57.09 ± 6.31] μIU/106 sperm, P < 0.05).
Conclusions: L-carnitine can effectively elevate sperm acrosin activity in male infertility patients, particularly in those with asthenozoospermia.
Keywords: L-carnitine; asthenozoospermia; oligozoospermia; sperm acrosin.