Effect of Zinc Supplementation on Urate Pathway Enzymes in Spermatozoa and Seminal Plasma of Iraqi Asthenozoospermic Patients: A Randomized Clinical Trial

Uric acid (UA) is crucial for sperm metabolism; it protects seminal plasma against oxidative damage. Zinc, too, plays a central role in sperm metabolism. The current study was designed to investigate the role of zinc supplementation on the qualitative and quantitative properties of seminal fluid, in parallel with the UA level and urate pathway enzymes in the semen of patients with asthenozoospermia.

The study design is a randomized controlled trial of 60 asthenozoospermic subfertile men. The current study, which was conducted for a year, involved 60 fertile and 60 asthenozoospermic subfertile men belonging to Hilla City, Iraq. Semen samples were obtained from the participants before and after treatment with zinc supplements. The levels of UA, xanthine oxidase (XO), adenosine deaminase (ADA) and 5--nucleotidase (5- NU) activities were determined in spermatozoa and seminal plasma of patients and healthy groups.

UA levels (P = 0.034) and 5'-NU activity (P = 0.046) were significantly lower and ADA (P = 0.05) and XO (P = 0.015) activities were significantly higher in infertile men than in healthy men. In addition to inducing an increase in UA (P = 0.001) level and 5'-NU activity (P = 0.001), treatment with zinc sulfate stimulated the decrease of ADA (P = 0.016) and XO (P = 0.05) activities.

Zinc supplementation restores UA levels and the activities of enzymes involved in the urate pathway (xanthine oxidase and adenosine deaminase) in the seminal plasma and spermatozoa of patients with asthenozoospermia to reference values. Supplementation of Zn compounds enhances the qualitative and quantitative properties of semen.