Effects of enzymatic and non-enzymatic antioxidants in diluents on cryopreserved bull epididymal sperm

Objective:To evaluate the supplementation effects of vitamin E,vitamin C,superoxide dismutase(SOD),and catalase to diluents on bull cryopreserved epididymal sperm.Methods:Sperm were retrieved from 20 bull testes and were then supplemented with 0.1 mM vitamin E,5.0 mM vitamin C,100.0 IU/mL SOD,and 100.0μg/mL catalase alone,or in a combination.The control treatment contained no addition.After supplementation,samples were frozen and stored in liquid nitrogen.The sperm parameters including motility,progressive motility,viability,acrosome integrity,plasma membrane integrity,kinematics and DNA damage were evaluated following the thawing process.Results:Vitamin E alone significantly increased the parameters of acrosome and membrane integrity compared to the control treatment(P<0.05).While compared to the control treatment,vitamin C had no improvement effect on sperm characteristics except for membrane integrity.Treatment of vitamin E+vitamin C had a significant improvement in total motility,progressive motility,viability,membrane and acrosome integrity compared to the control and other treatments(P<0.05).Compared to the control treatment,addition of SOD or catalase alone significantly improved the percentages of total motility,progressive motility,viability,membrane and acrosome integrity(P<0.05).Furthermore,SOD+catalase significantly increased total motility,progressive motility,viability,acrosome and membrane integrity characteristics compared to the catalase treatment(P<0.05).Vitamin E alone,vitamin E+vitamin C,and SOD in diluents decreased DNA damages and thereby improved the rate of intact sperm heads.Conclusions:Addition of 100.0 IU/mL SOD alone and 0.1 mM vitamin E+5.0 mM vitamin C,and also 5.0 mM vitamin C+100μg/mL catalase in a combination improves the quality of cryopreserved bull epididymal sperm and could be used for cryopreservation.

Protective effect of Scrophularia striata combined with trehalose and cysteine added to diluents on cryopreservd goat epididymal sperm

Objective:To evaluate antioxidant effects of Scrophularia(S.)striata ethanol extract,trehalose and cysteine added to diluents on cryopreserved goat epididymal sperms.Methods:Motility and standard motion parameters of sperm were assessed by using computer assisted sperm motility analysis system.Sperm viability was evaluated by eosin-nigrosin staining method.Hypo-osmotic swelling test was used to evaluate membrane health.Thiobarbituric acid testing was used to measure malondialdehyde(MDA)concentrations.To assess DNA fragmentation,sperm chromatin dispersion test was used.In Experiment 1,treatments consisting of basal Tris diluent supplemented with 25,50 or 100µg/mL of S.striata ethanol extract gave the best concentration to the freezing diluents.Experiment 2 was carried out to compare the best concentration of S.striata ethanol extract(50µg/mL)resulting from the first experiment with 150 mM trehalose and/or 5 mM cysteine alone or in combination.Results:S.striata ethanol extract(50µg/mL)significantly increased sperm viability,motility and progressive motility and at the same time decreased MDA concentration and DNA fragmentation compared to other treatments(P<0.05).In addition,all treatment groups resulted in viability,membrane health,total motility,progressive motility,curvilinear velocity,straightline velocity higher and MDA lower compared to the control group(P<0.05).Acrosome integrity was significantly higher in 50µg/mL of S.striata ethanol extract combined with cysteine,trehalose,or cysteine+trehalose groups than those in the control,trehalose,cysteine,and 50µg/mL of S.striata ethanol extract groups(P<0.05).Regarding DNA,extenders supplemented with 50µg/mL of S.striata ethanol extract,50µg/mL of S.striata ethanol extract+trehalose,and 50µg/mL of S.striata ethanol extract+trehalose+cysteine were superior to other treatments.Conclusions:Adding 50µg/mL of S.striata ethanol extract alone or in combination with trehalose and cysteine can improve the quality of cryopreserved epididymal sperms of goats.