Varicocele and oxidative stress

Abstract

A varicocele is an abnormal dilatation of the pampiniform plexus within the spermatic cord. It is the most common male infertility factor, with multiple potential etiologies involved in its development. However, despite ongoing extensive research on varicoceles, the exact mechanism(s) by which varicocele infl uences male fertility is not known. Recent studies have shown that infertile men with varicocele have higher levels of seminal oxidative stress (OS) markers, and/or lower seminal antioxidant levels, than do fertile men and infertile men without varicocele. The abnormally high levels of seminal OS biomarkers (e.g., reactive oxygen species, malonaldehyde) in infertile men with varicocele is clinically relevant as these markers have been associated with poor sperm function and reduced fertility potential. In addition, infertile patients with varicocele possess high levels of sperm DNA damage and the mechanism of varicocele-induced sperm DNA damage is believed to be at least in part due to OS. The observed improvement in seminal OS and sperm DNA damage after varicocele repair supports the premise that varicocele can induce seminal OS.