Therapeutic Potential of Different Injection Methods for Bone Marrow Mesenchymal Stem Cell Transplantation in Buslfan-Induced Male Rat Infertility

<b>Background:</b> In recent years, bone marrow derived mesenchymal stem cells (BM-derived MSCs) have emerged as a powerful cell-based therapy for various diseases, including male infertility. <b>Aim:</b> Demonstrating the efficiency of BM-derived MSCs transplantation by different routes of injection to home and repair testis of busulfan-induced azoospermic rats. <b>Material and methods:</b> In the present study, rat BM-derived MSC was isolated and characterized for mesenchymal &hematopoietic markers using flow-cytometry. Induction of infertility was induced by two successive doses of 10 mg/kg of busulfan. Azoospermic rats were treated by BM-derived MSCs which were injected via various routes (IP, IV, and local in testis). After 60 days; sperm analyses were performed beside mainly Biochemical, histopathological, immunohistological, and ultrastructural investigations. <b>Results:</b> BM-derived MSCs were expressed by CD44+ve, CD105+ve, CD106+ve, CD73+ve, CD34-ve, and CD45-ve. Sperm analysis showed a substantial improvement in sperm morphology, motility, and count following treatment with BM-derived MSCs. Caspase-3 and PCNA immunoexp ression accompanied with the levels of FSH, LH, testosterone, SOD, GSH and MDA depicted a considerable restoration of healthy levels after BM-derived MSCs treatment. The seminiferous tubules showed healthy morphology and spermatozoa were detected in their lumen according to the histopathological and ultrastructural analysis of BM-derived MSCs treated rats. Interestingly, BM-derived MSCs intravenous injection revealed the most significant infertility repair outcomes (P<0.05). <b>Conclusion:</b> Transplanted BM-derived MSCs had the potential to home in rat azoospermic testes and restore spermatogenesis. Consequently, the distinctive characteristics of BM-derived MSCs, such as their ability to differentiate and home, make them a promising cell-based therapeutic option for male infertility.