Impairment of reproductive function in a male rat model of non-alcoholic fatty liver disease and beneficial effect of N-3 fatty acid supplementation.

Non-alcoholic fatty liver disease (NAFLD) is closely associated with reduced levels of testosterone, which may affect fertility. Herein, we investigated whether NAFLD impairs the reproductive function of male rats. Male Sprague-Dawley rats were fed a high fat diet (HFD) until they developed NAFLD. N-3 polyunsaturated fatty acid (PUFA) was then given for 4 weeks to prevent hepatic steatosis. Testes weight and serum and testicular testosterone were significantly lower in rats with NAFLD compared with healthy controls. Testicular pathological changes in NAFLD rats included markedly reduced sperm number and motility, and the number of apoptotic spermatogenic cells was higher, which was consistent with a reduction in the number of tetraploid cells. Breeding experiments indicated that paternal NAFLD affected neither the sperm morphology nor the development of fetuses and offspring, but did prolong the days required for insemination. However, administration of N-3 PUFA alleviated the impairment of reproductive function. These results suggest that NAFLD impairs reproductive function in male rats by decreasing testicular testosterone synthesis, and N-3 PUFA treatment may have a beneficial therapeutic effect.