Effect of varicocele on sperm function and semen oxidative stress.

OBJECTIVE: To assess the effect of varicocele on sperm DNA integrity, mitochondrial activity, lipid peroxidation and acrosome integrity. PATIENTS AND METHODS: In all, 30 patients with a clinically diagnosed varicocele of grade II or III and 32 men without a varicocele were evaluated for sperm DNA fragmentation (comet assay), mitochondrial activity (3,3'-diaminobenzidine assay), lipid peroxidation (malondialdehyde) and acrosome integrity (fluorescent probe labelled peanut agglutinin). RESULTS: The varicocele group showed fewer spermatozoa with intact DNA (grade II, P= 0.040), more cells with inactive mitochondria (class III, P= 0.001), fewer cells with active mitochondria (class I, P= 0.005) and fewer spermatozoa with intact acrosomes (P < 0.001). Finally, no significant differences were observed in lipid peroxidation levels. CONCLUSION: Men with varicocele showed an increase in sperm DNA fragmentation and a reduction in mitochondrial activity and acrosome integrity. However, lipid peroxidation levels remained unchanged.

Adolescent varicocele: improved sperm function after varicocelectomy.

OBJECTIVE: To assess the effect of varicocelectomy on sperm function (DNA integrity and mitochondrial activity) and levels of lipid peroxidation in seminal plasma of adolescents. DESIGN: Prospective study. SETTING: Patients recruited from a local public school. PATIENT(S): Adolescents (14-19 years old), Tanner stages IV or V with varicocele grades II or III, attending a local public school. INTERVENTION(S): Two semen collections with a one week interval between collections before bilateral varicocele repair using subinguinal microsurgical varicocelectomy, and two semen collections with a one week interval between collections three months after the surgery. MAIN OUTCOME MEASURE(S): Rate of sperm DNA fragmentation as assessed by the Comet assay and categorized as classes I (no DNA fragmentation) to IV (high DNA fragmentation). Rate of mitochondrial activity as assessed by the diaminobenzidine assay and categorized as grades I (all mitochondria active) to IV (all mitochondria inactive). Levels of lipid peroxidation in seminal plasma by a colorimetric method that quantifies a lipid peroxidation subproduct (malondialdehyde). RESULT(S): Concerning DNA integrity, the samples after varicocelectomy showed more spermatozoa with intact nuclear DNA (grade I) and less spermatozoa with Comet grades II, III, and IV. Regarding mitochondrial activity, the samples after varicocelectomy showed less cells with inactive mitochondria (class III). No differences were observed in classes I, II, and IV. Concerning lipid peroxidation, no significant differences were observed. CONCLUSION(S): This study was able to demonstrate that varicocelectomy in adolescents is associated with increased sperm DNA integrity and mitochondrial activity. However, levels of seminal products of lipid degradation (malondialdehyde) are not different.

Sperm nuclear DNA fragmentation and mitochondrial activity in men with varicocele.

OBJECTIVE: To verify the impact of varicocele on semen quality and sperm function (DNA integrity and mitochondrial activity). DESIGN: Prospective study. SETTING: Patients in an academic research environment. PATIENT(S): Seventeen patients with a clinical diagnosed varicocele of grade II or III and 20 men without a varicocele. MAIN OUTCOME MEASURE(S): Rate of sperm DNA fragmentation as assessed by the Comet assay and categorized as classes I (no DNA fragmentation), II (little DNA fragmentation), III (meaningful DNA fragmentation), and IV (high DNA fragmentation). Rate of mitochondrial activity as assessed by the diaminobenzidine (DAB) assay and categorized as grades I (all mitochondria active), II (most mitochondria active), III (most mitochondria inactive), and IV (all mitochondria inactive). RESULT(S): No statistically significant differences were found between the study and control groups with respect to age, ejaculatory abstinence, and round cell count. Men with varicocele had significantly higher ejaculate volume, concentration of immotile sperm, and neutrophil count and lower mean percentage of sperm concentration, progressive motility, and morphology than men in the control group. The study group presented a lower percentage of sperm with little DNA fragmentation (class II) and a higher percentage of sperm with DNA fragmentation (class IV). In addition, the study group presented a greater percentage of sperm with inactive mitochondria (class III). CONCLUSION(S): Compared with men without varicocele, men with varicocele had a higher percentage of cells with DNA fragmentation and sperm with inactive mitochondria. Indeed, varicocele causes a decrease in motility, concentration, and morphology and an increase in volume and concentration of immotile sperm and neutrophils. The sperm functional evaluation (DNA fragmentation and mitochondrial activity) could be important factors in deciding treatment options for men with varicocele.