LAUSR

One of the major causes of the decline in semen quality appears to be the elevated levels of oxidative stress. Leaves of Toona Sinensis (TSL) have been used as a traditional medicine for treatment of certain male reproduction-related disorders in Chinese ancient medical books; however, the scientific data are limited. In the present study, human spermatozoa treated with hydrogen peroxide (H2O2) were used to investigate the protective function of TSL-6 under oxidative stress. The intracellular reactive oxygen species (ROS) levels of human spermatozoa were increased after 0.2 mmol/L H2O2 treatment and the elevated levels were diminished by TSL-6 dose dependently. The protection of TSL-6 against oxidative stress in human spermatozoa was further substantiated by increasing sperm motility assay including computer assisted sperm analysis (CASA), percentage of high MMP cells, ATP production, percentage of double strand DNA cells, and decreasing cell death. Our results suggested that TSL-6 improved functions of spermatozoa under oxidative stress via decreasing ROS level and cell death. In addition, TSL-6 increased sperm motility, MMP, ATP levels, and maintained the integrity of chromatin structure. TSL-6 is beneficial for human sperm and is potentially developed into functional foods for infertile men under oxidative stress.