Effects of Testosterone on antioxidant systems in male secondary hypogonadism.

Oxidative stress is involved both in metabolic syndrome and male infertility. Hypogonadism is also associated with increased risk for cardiovascular disease. To investigate the role of gonadal steroids in systemic antioxidant regulation, we determined plasma CoenzymeQ10 (CoQ10) and total antioxidant capacity (TAC) in postsurgical hypopituitaric patients. Twenty-six patients aged 28 55 years were studied 6 12 months after surgery. CoQ10 levels were measured by high-performance liquid chromatography and TAC by spectroscopy with the use of the mioglobin-H2O2 system, which, in interacting with chromogen 2,2I-azinobis-(3- ethylbenzothiazoline-6-sulfonate), generates a radical after a latency time (LAG) that is proportional to antioxidant content. Sixteen patients presented low testosterone values; in 10 patients hypogonadism was isolated, and in 6 patients hypothyroidism also was present. CoQ10 levels were significantly lower in isolated hypogonadism than in normogonadism. Testosterone treatment, performed in those patients with isolated hypogonadism, induced a significant enhancement both in CoQ10 level and LAG. CoQ10 and LAG values correlated significantly, suggesting an interrelationship between different antioxidants. Our data suggest that hypogonadism could represent a condition of oxidative stress, in turn related with augmented cardiovascular risk.