An increase in reactive oxygen species (ROS) or decrease in antioxidant barriers can provoke lipid peroxidation of the membranes or DNA damage of the spermatozoa. The aim of this work is to study the effect of the different degrees of oxidative stress generated by H2 O2 incubation on total motility, kinetics, and DNA fragmentation of zebrafish (Danio rerio) spermatozoa. For this process, experimental groups were incubated in 50 µM (Low; L) and 200 µM (High; H) H2 O2 , respectively, for 20 min at 4ºC. Sperm motility parameters were obtained with a computer-assisted sperm analysis (CASA) system. Sperm DNA fragmentation (SDF) was assessed using the sperm chromatin dispersion test. Both low and high H2 O2 concentration groups showed lower motility than control groups. Progressive motility of spermatozoa incubated in the H group dropped rapidly in comparison with other groups. Regarding SDF, the control and L groups had significantly lower values than the H group (25.0% and 31.6% vs. 48.1% fragmented sperm for C, L, and H groups, respectively; p < 0.05). Sperm motility, mostly progressive motility, decreased as H2 O2 concentration increased, mainly when time after sperm activation increased. SDF increased as the H2 O2 concentration increased. However, measurements of the halo area did not agree with the subjective SDF rate.
Keywords: CASA-mot; DNA fragmentation; hydrogen peroxide; sperm chromatin dispersion; zebrafish.
© 2018 Blackwell Verlag GmbH.