Fluorometric Assessment of Sulfhydryl Oxidase Activity: Optimization by Response Surface Methodology.

Sulfhydryl oxidase was studied using a spectrofluorometric assay. The current protocol operates by using a combination of hemoglobin (HB) and hematin (HT) as a peroxidase mimic to catalyze the H2O2-dependent oxidation of thiamine. The response surface methodology (RSM) is used to optimize the new method. The current method is very accurate, sensitive, and linear up to 200 IU. When compared to the colorimetric method, the method produced a satisfactory correlation. The novel protocol is being used to evaluate asthenospermic patients' and fertile men's seminal sulfhydryl oxidase activity. The current protocol was used to determine reference values for seminal sulfhydryl oxidase activity. Due to the fact the newly developed spectrofluorometric method is more sensitive and precise than other colorimetric methods, and because thiamine is less expensive than other types of probes used in colorimetric and spectrofluorometric methods, it is likely to find widespread use among scientists studying sulfhydryl oxidase activity in biological tissues. The present method's analytical recovery yielded high specific findings.

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

BACKGROUND: Uric acid (UA) is crucial for sperm metabolism as it protects seminal plasma against oxidative damage. Zinc also plays a central role in sperm metabolism. The current study was designed to investigate the role of zinc supplementation on qualitative and quantitative properties of seminal fluid, in parallel with the UA level and urate pathway enzymes in the semen of patients with asthenozoospermia. MATERIALS AND METHODS: The study was designed as a randomized controlled trial of 60 asthenozoospermic subfertile men. The current study, which was conducted during one 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 both groups. RESULTS: UA levels (P=0.034) and 5'-NU activity (P=0.046) were significantly lower but ADA (P=0.05) and XO (P=0.015) activities were significantly higher in infertile men than in healthy men. Treatment with zinc sulfate induced an increase in UA (P=0.001) level and 5'-NU activity (P=0.001), but a decrease in ADA (P=0.016) and XO (P=0.05) activities. CONCLUSION: Zinc supplementation restores UA levels and the activities of enzymes involved in the urate pathway (XO and ADA) 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 (Registration number: NCT03361618).