Effects Of Varicocele And Age On The Sperm DNA Damage

Objective: This study was designed to explore the relationship between men’s age andDNA damage and semen major parameters and its possible mechanism. To explore thelevels of sperm DNA damage in infertile males with varicocele and the effect of highligation of the spermatic vein (HLSV) on DNA damage in varicocele (VC) patients,and investigate the test of sperm DNA damage to evaluate the feasibility of the VCpatients’ fertility and the effect of HLSV．Methods：102healthy male (range:20-46years) were divided into5groups accordingto the age: Group1:20-24years old, Group2:24-29, Group3:30-34, Group4:35-39,Group5:40-46. Standard semen analysis and sperm DNA damage levels were measuredin all samples. Sperm DNA damage was tested by sperm chromatin dispersion (SCD)test. The correlation of age, sperm DNA damage and semen major parameters wasanalyzed by curve regression. Semen samples from58patients with clinical varicoceleand30normozoospermic donors were examined. Varicocele sperm samples wereclassified as normal or abnormal according to World Health Organization guidelines.Sperm DNA damage was evaluated by the sperm chromatin dispersion (SCD) text.24VC patients underwent HLSV, each of them underwent sperm analysis and DNAdamage evaluation before and3months after HLSV.Results：Men above35years had significantly high levels of DNA damage comparedwith younger men (P <0.001). Significantly positive correlation was found betweensperm DNA damage index and the age of male（r=0.439P<0.001）. There was nodifference in semen major parameters between all group. Sperm motility were decreasedwith male’s age increased（r=-0.258p=0.009）. There was no significantly correlation between the semen major parameters and sperm DNA damage index. DNA damage levelswere significantly greater in patients with varicocele, either with normal (23.94±6.04)or with abnormal (33.64±7.11) semen profile, compared with controls (10.78±5.01)(P<0.001). Compared with pre-operation，HLSV achieved a significant decreasesin the percentage of sperm DNA damage (P<0.001).Conclusion：Sperm DNA damage index are increased with male’s age, Sperm DNAdamage levels are significant higher in seminal ejaculates of healthy men older than35years. Sperm motility with age are on a downward trend. The presence of a varicocele isassociated with high levels of DNA damage spermatozoa. HLSV can effectivelydecreases in the percentage of sperm DNA damage. For VC patients’ fertility and theeffect of HLSV, the test of sperm DNA damage is a good and feasibility evaluationmark.