In vitro and in vivo lineage conversion of bone marrow stem cells into germ cells in experimental Azoospermia in rat

Abstract

The present study is conducted to assess in vitro transdifferentiation of bone marrow derived mesenchymal stem cells (MSCs) into germ cells and in vivo transdifferentiation into spermatids and spermatocytes in the seminiferous tubules of azoospermic rats. Forty eight male rats were included in the study and were divided into: group 1; control rats, group 2; experimental azoospermic rats, group 3; azoospermic rats received undifferentiated MSCs. Group 4; azoospermic rats received transdifferentiated MSCs into germ cells. Quantitative real time PCR was conducted to assess gene expression of a primordial germ cell marker (VASA), stem cell specific markers (Oct4, SSEA-1 and SSEA-3), specific molecular markers of germ cells (c-Kit, Daz1); premeiotic marker (Daz1) and post-meiotic markers (c- Kit, Stra 8). Histopathological examination of rat testicular tissue was also conducted. Results revealed that 12 weeks after transplantation, fluorescent labeled MSCs were detected in the seminiferous tubules of the testes of group 3 and group 4 rats. In group 3 and 4, stem cell specific markers; Oct4, SSEA-1 and SSEA-3 were detected. In group 4, genes of primordial germ cell marker; VASA, premeiotic marker; Daz1and post-meiotic markers; c-Kit, Stra 8 were expressed. Daz1 was also expressed in group 3 rats to a significantly lower extent in comparison to group 4 rats. Spermatocytes and spermatids were detected in testicular tissue of group 4 rats. In conclusion, MSCs have potentials for in vitro transdifferentiation into germ cells and in vivo transdifferentiation into spermatids and spermatocytes.