Cytokines analysis, microRNAs expression and sperm DNA damage in patients with varicocele

ABSTRACT Purpose: Varicocele is a common cause of male infertility. The purpose of our work was to evaluate the cytokine profile in seminal plasma of varicocele patients; to integrate it with the seminal characteristics, the smoking habits, the severity of vascular disease; to investigate the role of miRNAs involved in the regulation of inflammatory pathway. Methods: Seminal analysis was conducted on seminal plasma of 84 varicocele patients and 85 normozoospermic controls. All patients were classified as smokers/non-smokers and according to the varicocele gravity (Low and High grade). We analyzed the sperm DNA fragmentation % (SDF) by TUNEL, cytokines’ concentration (IL-1β, IL-6, TNF-α, IFN-γ, IL-8, IL-10, IL-17) by Luminex xMAP (Bio-Rad) and the miRNAs’ expression (hsa-mir-106a, hsa-mir-19a-3p, hsa-mir-24a-3p) by qRT-PCR in seminal plasma. Results: Varicocele showed significantly lower seminal parameters quality, although the values fall in the normality range, and a higher SDF. No difference was observed according to the smoking habit and varicocele gravity. A significant reduction of IFN-g, IL6, TNF-α, and an increase of IL-10 have been observed in varicocele. The expression of has-mir-19a, has-mir-24a-3p, has-mir-106a didn’t differ in varicocele patients. Conclusion: Our study identify a negative effect of varicocele on seminal quality with no influence of smoking habits and varicocele severity. The reduction of the pro-inflammatory cytokines IL-6, TNF-α and IFN-γ and the increase of anti-inflammatory IL -10 suggest a pattern of chemical mediators related to a chronic inflammatory condition in varicocele patients, that could cause severe testicular damage if prolonged in time.