RESUMO
Background: bone morphogenetic protein 4 [BMP4] is a significant signaling molecule that involves in initiating of differentiation and performs multifunctional effects on embryonic stem cells [ESCs] and embryos
Objective: the goal of the present study was to evaluate an in vitro differentiation model of mouse embryonic stem cells into germ cells, using BMP4
Materials and Methods: in this experimental study, we used Oct4-GFP mouse ESCs to form embryoid body [EB] aggregations for two days. Then, single cells from EB were cultured for four days with BMP4. Using MTT assay and gene expression levels for evaluation of Mvh and Riken by real-time RT-PCR of six concentrations, 12.5 ng/ ml BMP4 was determined as an optimized dose. Then, the expression level of Fkbp6, Mov10l1, 4930432K21Rik, Tex13, Mvh, Scp3, Stra8, Oct4 were evaluated. Flow cytometry and immunostaning were used to confirm the findings of the real-time RT-PCR
Results: in the +BMP4 group, the genes encoding Riken [p
Conclusion: down-regulation of Oct4, expression of germ cells genes and meiosis markers expression raise this hypothesis that ESCs were differentiated by BMP4, and may be introduced into the first meiosis as germ cell-like cells
RESUMO
BACKGROUND: Mesenchymal stem cells (MSCs), have been suggested as a potential choice for treatment of male infertility. Yet, the effects of MSCs on regeneration of germinal epithelium of seminiferous tubules and recovery of spermatogenesis have remained controversial. In this research, we have evaluated and compared the fate of autologous bone marrow (BM)-MSCs during three different periods of time- 4, 6 and 8 weeks after transplantation into the testes of busulfan-induced infertile male rats. METHODS: Rats BM samples were collected from tibia bone under anesthesia. The samples were directly cultured in culture medium. Isolated, characterized and purified BM-MSCs were labeled with PKH26, and transplanted into the testes of infertile rats. After 4, 6 and 8 weeks, the testes were removed and underwent histological evaluations. RESULTS: Immunohistochemical analysis showed that transplanted BM-MSCs survived in all three groups. Some of the cells homed at the germinal epithelium and expressed spermatogonia markers (Dazl and Stella). The number of homed spermatogonia-like cells in 4-week testes, was more than the 6-week testes. The 8-week testes had the least numbers of homed cells (p<0.05). Immunostaining for vimentin showed that BM-MSCs did not differentiate into the sertoli cells in the testes. CONCLUSIONS: From our results, it could be concluded that, autologous BM-MSCs could survive in the testis, migrate onto the seminiferous tubules basement membrane and differentiate into spermatogonia. Although, no more differentiation was observed in the produced spermatogonia, generation of such endogenous GCs would be a really promising achievement for treatment of male infertility using autologous stem cells.