Abstract
Background: Zinc and vitamin E affect the metabolism of testosterone and inflammatory factors. We aimed to evaluate the effect of zinc and vitamin E supplementation on plasma testosterone levels and inflammatory markers in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: This study was a secondary analysis of a previously published randomized controlled trial in a subsample of male patients undergoing CABG surgery. Patients in the zinc-vitamin E group (n = 27) received oral zinc (120 mg) and vitamin E (1200 international units) one day prior to surgery, followed by 30 mg of zinc and 200 units of vitamin E per day for three weeks after surgery. Patients in the control group (n = 25) received a placebo. Plasma levels of total testosterone, cortisol, interleukin-6 (IL-6), and white blood cell toll-like receptor-4 (TLR-4) gene expression were determined at three-day and three-week intervals following surgery. Changes in these markers were analyzed using a repeated-measures analysis of variance. Results: A comparison of the groups revealed no significant difference in the concentration of plasma total testosterone levels (P = 0.059) or cortisol. Three weeks following the surgical procedure, a positive correlation was observed between the change in plasma zinc concentrations and the change in plasma testosterone levels (r = 0.32; P = 0.025). The administration of zinc and vitamin E supplements resulted in a reduction in plasma IL-6 levels on postoperative day 3 (P = 0.025), while no significant effect was observed in week 3 (P = 0.091). The expression of the TLR-4 gene in WBCs was found to be lower in the zinc-vitamin E group compared to the placebo group on day 3 (P = 0.051) and week 3 (P = 0.025). Conclusions: The administration of zinc and vitamin E to patients undergoing CABG was associated with a relative improvement in postoperative inflammatory markers. Plasma zinc levels demonstrated a correlation with testosterone levels, suggesting a potential avenue for further research in these patients.