Induction of spermatogenesis after stem cell therapy of azoospermic guinea pigs

Bone marrow-derived mesenchymal stem cells (BM-MSCs) provide a large quantitative alternative source for regenerative medicine. This study was undertaken to determine the effect of BM-MSCs in the treatment of busulfan-induced azoospermia in guinea pigs. BM-MSCs were isolated from the femur bones of 6 adult guinea pigs as the donor group, and characterized by morphology, MSC markers and osteogenic and adipogenic differentiation. A dose of 40 mg/kg of busulfan was administered at a 21 day interval to induce azoospermia in 6 guinea pigs. Thirty-five days after the second injection of busulfan, transplantation of 1x10(6) BM-MSCs was performed into the seminiferous tubules of the left testes. The right testis was considered as the positive busulfan treated control. The testes of the donor group were applied as an intact normal control. Then, 60 days after cell therapy, histopathological and histomorphometric evaluations of the testes were performed. The seminiferous tubules treated with BM-MSCs, similar to the intact group, showed a normal appearance of spermatogenesis in comparison to the busulfan-induced azoospermic testes. In conclusion, BM-MSCs were effective in the treatment of azoospermia in a guinea pig model where they restore the fertility of busulfan-induced azoospermic animals after transplantation of BM-MSCs. Therefore, this report could open a window in future to the possibility of BM-MSCs transplantation in the treatment of azoospermia in humans, but more studies should be undertaken for further verification.