The identity and behavior of mouse spermatogenic stem cells have been a long-standing focus of interest. In the prevailing "As model," stem cell function is restricted to singly isolated (As) spermatogonia. By examining single-cell dynamics of GFRα1+ stem cells in vivo, we evaluate an alternative hypothesis that, through fragmentation, syncytial spermatogonia also contribute to stem cell functi...

Effects of adrenalectomy and administration of gonadotropins on cell counts of different cell types of spermatogenesis and morphology of the Leydig cells were studied in 30 day old mice. Adrenalectomy (duration, 12 days; age at autopsy 42 days) caused a significant decrease in the diameters of seminiferous tubules and Leydig cell nucleus and, cell counts of intermediate spermatogonia, round and...

Zebrafish spermatogonial cell cultures were established from Tg(piwil1:neo);Tg(piwil1:DsRed) transgenic fish using a zebrafish ovarian feeder cell line (OFC3) that was engineered to express zebrafish Lif, Fgf2 and Gdnf. Primary cultures, initiated from testes, were treated with G418 to eliminate the somatic cells and select for the piwil1:neo expressing spermatogonia. Addition of dorsomorphin, ...

The last 100 years have seen a concerning decline in male reproductive health associated with decreased sperm production, sperm function and male fertility. Concomitantly, the incidence of defects in reproductive development, such as undescended testes, hypospadias and testicular cancer has increased. Indeed testicular cancer is now recognised as the most common malignancy in young men. Such ca...

A quantitative analysis of germ-cell populations in normal, hypophysectomized (Hx), and Hx-hormone-treated animals was undertaken during periods of regression that were characterized as intermediate, between short-term and long-term regression of the testis. Twenty-one groups of adult rats were administered either follicle-stimulating hormone (FSH), growth hormone, thyroid-stimulating hormone (...

Spermatogenesis is the process by which spermatozoa are generated from spermatogonia. This cell population is heterogeneous, with self-renewing spermatogonial stem cells (SSCs) and progenitor spermatogonia that will continue on a path of differentiation. Only SSCs have the ability to regenerate and sustain spermatogenesis. This makes the testis a good model to investigate stem cell biology. The...

Spermatogenesis, the process by which haploid sperm cells are produced from a diploid precursor cell, is essential for sexual reproduction. Here, we report that RING-finger protein 138 (Rnf138) is highly expressed in testes, especially in spermatogonia and spermatocytes. The role of Rnf138 in spermatogenesis was examined using a Rnf138-knockout mouse model. Rnf138 deficiency resulted in increas...

Interest in spermatogonia has grown in recent years as a result of exciting developments in stem cell research in general and the development of new research tools allowing the isolation, culture and transplantation of these cells. This review focuses on the methodological breakthroughs and highlights the recent findings that have substantially increased understanding of spermatogonial physiolo...

Retinoic acid is like a steroid hormone that plays a role in embryo formation, proliferation of spermatogonia cells, ephitelial cells differentiation and organogenesis. Retinoic acid can influences seminiferous tubule formation during embryonic testis development and also play a role in the regulation of ovarian function and female reproductive tract by suppressing the hormones FSH receptor exp...

BACKGROUND This study was conducted to identify and characterize repopulating spermatogonial stem cells (SSCs) in the adult human testes. METHODS Testes biopsies from obstructive azoospermic patients and normal segments of human testicular tissue were used. Flow cytometry, real-time PCR and immunohistochemical analysis were performed. Purified human spermatogonia were transplanted into busulf...