Enhanced Protective Effects of Combined Treatment with β-Carotene and Curcumin against Hyperthermic Spermatogenic Disorders in Mice

Scrotal hyperthermia leads to oxidative stress and apoptosis in spermatogenic cells, which subsequently causes male infertility. In this study, we examined the effects of β-carotene and/or curcumin on heat-stress- (HS-) induced testicular injuries in mice. ICR male mice (8 weeks old) were consecutively treated with β-carotene (10 mg/kg) and/or curcumin (20 mg/kg) orally once a day for 14 days and then subjected to single exposure with scrotal HS at 43°C for 15 min on day 7. HS induced a significant reduction in testicular weight, appearance of multinucleated giant cells, and desquamation of germ cells in destructive seminiferous tubules, as well as degenerative Leydig cells. Moreover, HS reduced the superoxide dismutase (SOD) activity and mRNA levels of mitochondrial SOD, phospholipid hydroperoxide glutathione peroxidase, B-cell lymphoma-extra-large, and 3β-hydroxysteroid dehydrogenase, with increases in lipid peroxidation levels and mRNA levels of BCL2-associated X protein and caspase-3 relative to those of the control group. However, these changes were significantly recovered by combined treatment with β-carotene and curcumin after HS. These findings indicate that the combined treatment with β-carotene and curcumin might be a valuable protective agent to ameliorate hyperthermic spermatogenic disorders via its potent antioxidative, antiapoptotic, and androgen synthetic effects.