The effects of Wharton’s jelly MSCs secretomes for restoring busulfan-induced reproductive toxicity in male mice

Several studies investigated the application of Mesenchymal stem cells (MSCs) for treating spermatogenic disorders. Considering the limitation of MSC application, the present study aimed to compare Wharton's jelly MSCs secretomes, including condition medium (CM) 10-fold concentrated (CM10), 20-fold concentrated CM (CM20), and extracellular vesicles (EVs) to restore busulfan-induced damage on male mice reproduction. So, Wharton's jelly MSCs were cultured, CM was collected, and EVs were isolated. Seventy-two mice were randomly assigned to nine groups, including Control, Busulfan 1 month (1M), Busulfan 2 months (2M), CM10, Busulfan + CM10, CM20, Busulfan + CM20, EVs, and Busulfan + EVs groups. Sperm characteristics, DNA maturity, DNA fragmentation index (DFI), and testicular gene expression were evaluated. Data analysis revealed that CM10 significantly improved sperm plasma membrane integrity, sperm DNA maturity, and DFI in the Busulfan + CM10 group compared to the Busulfan 2M group. Although CM20 and EVs showed a non-significant improvement. Gene expression analysis showed busulfan administration significantly decreased the expression of AR, CREB1, and PLCζ genes, while CM10 significantly restored CREB1 gene expression. The present study demonstrated that CM10 is more effective than CM20 or EVs in reducing busulfan-induced reproductive toxicity.