Effects of combined antioxidant supplementation on human sperm motility and morphology during sperm manipulation in vitro

Abstract

Objective: To evaluate the effect of antioxidant combinations on human sperm motility and morphologic normality during preparation and in vitro incubation to improve sperm quality for assisted reproductive technology (ART).

Design: Prospective study.

Setting: Laboratory.

Patient(s): Six fertile males, 21 to 25 years of age, after 3 days of sexual abstinence.

Intervention(s): Sperm retrieved from patients with normal fertility prepared and incubated in vitro in medium supplemented with taurine, cysteine, and/or glutathione.

Main outcome measure(s): Motility indices, including motility (MOT), average path velocity (VAP), curvilinear velocity (VCL), straight-line velocity (VSL), and morphologic normality.

Result(s): Taurine supplementation during sperm preparation had no significant effects on motility or morphologic normality. However, when sperm was incubated for 24 hours under taurine-supplemented conditions, the rates of reduction in MOT, VAP, VCL, and VSL were statistically significantly decreased compared with taurine-free conditions. Morphologic normality was maintained, regardless of taurine treatment. The optimal taurine concentration for improving sperm motility and morphologic normality during preparation and in vitro incubation was 1 mM. Subsequently, combined treatment with 1 mM taurine, 1 mM cysteine, and 1 mM glutathione induced statistically significant synergistic effects on MOT, VAP, VCL, and VSL without any alteration of morphologic normality.

Conclusion(s): Combined treatment with taurine, cysteine, and glutathione statistically significantly ameliorated the reduction in sperm motility during in vitro manipulation of human sperm.

Keywords: Antioxidants; human sperm; morphology; motility.