Oxidative damage can induce serious spermatogenic disorders, cause testicular tissue pathological damage, decrease testicular index and sperm count, and increase sperm deformity rate, thus causing male infertility. The present study aimed to investigate the effects of Morinda officinalis polysaccharide (MOP) upon the function of testicular Leydig cells and the underlying mechanisms, to provide novel insights into clinically treating male infertility. Leydig TM3 cells were treated with H2O2 to induce oxidative damage. Cell proliferation was detected using CCK-8 assay and EdU staining. The protein level of testicular interstitial cell biomarkers and mitochondrial signaling pathway-associated proteins was detected using Western blot. SA-β-gal staining was used to detect cell senescence. The levels of intracellular reactive oxygen species (ROS) were detected using flow cytometry. Additionally, SOD, CAT, GSH-Px, MDA, and ATP levels were detected with biochemical methods. Mitochondrial damage was traced using JC-1 and Mito-tracker dyes. For in-vivo validation, the Leydig cell elimination model was established in rats by an intraperitoneal injection of Ethane dimethane sulfonate (EDS). MOP effects on rat reproductive function (such as testicular pathological changes and sperm morphology, activity, and quantity) and Leydig cell function (such as levels of serum testosterone and biomarkers) were evaluated. MOP promoted testicular interstitial cell proliferation and testosterone secretion, attenuated testicular pathological damage, and improved sperm morphology, activity, and quantity. For mechanism, MOP can reduce ROS-induced oxidative damage to cells and mitochondria. Furthermore, MOP can activate the SIRT1/PGC-1α pathway and the level of mitochondrial-related functional biomarkers. SIRT1 inhibitor EX-527 could reverse the protective effect of MOP on Leydig cells. MOP can alleviate ROS damage to testicular Leydig cells, promote testosterone secretion, and improve male rat reproductive function. MOP was a potential drug for treating male infertility in the clinic.
Fu et al. (Thu,) studied this question.