Toona sinensis Leaf Aqueous Extract Improves the Functions of Sperm and Testes via Regulating Testicular Proteins in Rats under Oxidative Stress

Toona sinensis leaf (TSL) is commonly used as a vegetable and in spice in Asia. In this study, feeding with aqueous extract of TSL (TSL-A) alleviated oxidative stress and recovered the motility and functions of sperm in rats under oxidative stress. Protein expressions in testes identified by proteomic analysis and verified by Western blot demonstrated that TSL-A not only downregulated the level of glutathione transferase mu6 (antioxidant system), heat shock protein 90 kDa-β (protein misfolding repairing system), cofilin 2 (spermatogenesis), and cyclophilin A (apoptosis) but also upregulated crease3-hydroxy-3-methylglutaryl-coenzyme A synthase 2 (steroidogenesis), heat shock glycoprotein 96, and pancreatic trypsin 1 (sperm-oocyte interaction). These results indicate that TSL-A promotes the functions of sperm and testes via regulating multiple testicular proteins in rats under oxidative stress, suggesting that TSL-A is a valuable functional food supplement to improve functions of sperm and testes for males under oxidative stress.