Sperm motion analysis in rats treated with adriamycin and its applicability to male reproductive toxicity studies

Adriamycin (ADR), an anticancer drug which induces testicular toxicity, was administrated to Slc:SD male rats at doses of 0.5, 1.0, and 2.0 mg/kg intravenously once a week for 4 weeks. The males treated with ADR were mated with untreated females, and sperm analyses (motion, count, and morphology) were performed. Sperm motion was analyzed by Hamilton-Thorne Sperm analyzer (HTM-IVOS) to investigate the useful parameters. Copulated females were necropsied at Day 13 of gestation, and reproductive status was evaluated. In ADR-treated groups, the testicular weight was dose-dependently decreased. Associated with this decrease was a depletion of the number of spermatogonia noted histopathologically at all dosage levels. Sperm morphological abnormalities, which were classified as tailless sperm and/or no-hook head sperm, were increased in both the 1.0 and 2.0 mg/kg groups. The males treated with ADR at 1.0 and 2.0 mg/kg had a decreased number of sperms per cauda epididymis. In sperm motion analysis, decreases in the percentage of motile sperm, percentage of progressive sperm, and sperm velocity (straight line velocity and curvilinear velocity) were noted at 2.0 mg/kg. Impaired fertility was noted at 2.0 mg/kg in the form of decreased numbers of implantations and live embryos, and an increased number of pre-implantation losses. In conclusion, ADR induced deterioration of sperm motion and sperm content, which were responsible for the adverse effect on male fertility. The most sensitive indicators to detect male reproductive toxicity induced by ADR were testicular weight and histopathological findings in the testis. Among the parameters generated by HTM-IVOS, the percentage of motile sperm, the percentage of progressive sperm, and sperm velocity are useful for assessing male fertility.