A Preliminary Study About Protective Effects And Mechanism By Adding Lycopene On Human Spermatozoa During Cryopreservation

Objective:The aim of this study is to evaluate protective effects and mechanismof adding various concentrations of Lycopene to semen cryoprotectantson human spermatozoa during cryopreservation.Methods:Semen samples of16volunteer were chosen from September2013to February2014at Jilin sperm bank in the First Hospital of JilinUniversity. Computer-assisted semen analysis parameters(CASA)analysed sperm motility (a+b grade) and viability (a+b+c grade) beforefreezing and after thawing.Thiobarbiturieaeid (TBA) assay measure theMDA content as an indicator of the membrane lipid peroxidation.Terminal deoxynucleoitidy Transferase Mediated Nick End Labeling(TUNEL) measured positive cells ratio as an indicator of sperm DNAintegrity by using Laser scanning confocal microscopy. JC-1notation detected mitochondrial membrane potential as an indicator of reflectingmitochondrial damage by using Laser scanning confocal microscopy.Results:After freezing-thawing，sperm progressive motility and vitality ineach group have a lower level than the fresh group(P<0.05). Themitochondrial membrane potential by adding different concentrations oflycopene was significantly higher than the control group(P<0.05).Thegroup of adding5umol/L lycopene group whose percentage ofTUNEL-positive cells was significantly lower than the control group (P<0.05). The else of experimental group showed no statistically significantthan the control group (P>0.05)Conclusinon:Cryopreservation can damage the sperm motility and vitality.Addinglycopene on semen sample can protect the mitochondria fromoxidative stress. Adding the appropriate concentration of lycopene canprotect the sperm DNA. Lycopene can act as antioxidants to improvesperm quality by adding the appropriate concentration.