N-(3-methozybenzyl)-(9Z,12Z,15Z)-octadecatrienamide from maca (Lepidium meyenii Walp.) ameliorates corticosterone-induced testicular toxicity in rats

Maca has been traditionally used as a food source to enhance energy and fertility. Many studies have shown that maca aqueous extract (AEM) promotes spermatogenesis. However, studies on whether maca ethanol extract (EEM) can promote spermatogenesis are limited. In this study, a corticosterone (CORT)-induced testicular toxicity model was chosen to evaluate the effects of EEM and N-(3-methozybenzyl)-(9Z,12Z,15Z)-octadecatrienamide (M 18:3) on spermatogenesis. MEE and M 18:3 increased the sperm concentration and sperm motility, decreased the production of abnormal sperm, and increased the number of spermatogonia and primary spermatocytes in the seminiferous tubules of CORT-induced rats. Moreover, MEE and M 18:3 had no effects on the serum concentrations of LH, FSH, and T, the mRNA levels of GnRH (gonadotropin releasing hormone) in the hypothalami, and the positive expression rates of testicular androgen receptor (AR) in CORT-induced rats. Furthermore, MEE and M 18:3 decreased MDA levels and the positive expression rates of TUNEL, whearas increased the activities of SOD, CAT, GSH-Px, and GST, and the contents of GSH in the testicles of CORT-induced rats. In addition, MEE and M 18:3 alleviated CORT-induced reduction in the positive expression rates of PCNA and Ki67 in the testicles of rats. Besides, EEM and M 18:3 reduced the expression levels of Keap-1 and increased the expression levels of Nrf2, HO-1, γ-GCS, and NQO1 in the testicles of CORT-induced rats. In summary, the protective effects of EEM and M 18:3 may be attributed to the anti-oxidative and anti-apoptotic properties.