Effect of Metformin on Spermatogenesis Restoration Following Spermatogonial Stem Cell Transplantation in An Azoospermia Mouse Model

Objective: Spermatogonial stem cell transplantation (SSCT) could be a helpful strategy for fertility restoration in patients with childhood cancer. Additionally, using metformin as an antioxidant may help mitigate damage caused by chemotherapy. This study aimed to evaluate the protective effects of metformin against oxidative stress caused by busulfan and cadmiuminduced damage while examining its role in enhancing spermatogenesis restoration following SSCT. Materials and Methods: In this experimental study, a long-term infertility mouse model was created using cadmium and busulfan treatment (BC, n=10). Cryopreserved SSCs were transplanted either alone (cryo+SSCT, n=10) or in combination with metformin (cryo+MET+SSCT, n=10). These experimental groups were compared to a control group (n=10). Flow cytometry was used to assess the protective effect of metformin against reactive oxygen species (ROS) production, and immunofluorescence evaluated proliferation and differentiation markers. Results: The results of our study showed that ROS production decreased significantly in the cryopreservation group with metformin (P<0.05). The expression of proliferation and differentiation markers after transplantation was significantly increased in the cryopreservation group with metformin compared to the cryopreservation group containing a basic Conclusion: Transplantation of SSCs combined with metformin significantly enhances spermatogenesis and improves the homing efficiency of transplanted SSCs. This approach holds great potential for restoring fertility in clinical settings, particularly in childhood cancer survivors.