Fertility genes required for sperm stem cells
The underlying cause of male infertility is unknown for 30 percent of cases. In a pair of new studies, researchers have determined that the reproductive homeobox (RHOX) family of transcription factors -- regulatory proteins that activate some genes and inactivate others -- drive the development of stem cells in the testes in mice. The investigators also linked RHOX gene mutations to male infertility in humans.
Journal of Cellular Physiology, EarlyView.
Publication date: Available online 5 April 2018 Source:Stem Cell Reports Author(s): Satoshi Watanabe, Mito Kanatsu-Shinohara, Narumi Ogonuki, Shogo Matoba, Atsuo Ogura, Takashi Shinohara Adeno-associated virus (AAV) penetrates the blood-brain barrier, but it is unknown whether AAV penetrates other tight junctions. Genetic manipulation of testis has been hampered by the basement membrane of seminiferous tubules and the blood-testis barrier (BTB), which forms between Sertoli cells and divides the tubules into basal and adluminal compartments. Here, we demonstrate in vivo genetic manipulation of spermatogonial stem cell...
Non-obstructive azoospermia (NOA), particularly Sertoli cell-only (SCO), is the most severe form of male factor infertility and is classically thought to lack germ cells and spermatogenic stem cells (SSCs). However, evidence from microsurgical testicular sperm extraction (micro-TESE) on men with SCO has revealed the presence of focal areas of full spermatogenesis, suggesting the possible presence of SSCs in some patients with SCO lacking mature sperm. To determine whether gene products from SSCs could be detected in SCO, transcriptome analysis using next-generation sequencing (NGS) was performed using human biopsied testicular samples.
The objective of this study is to translate the in vitro propagation system using human KS testicular cells for future clinical application.
Finding sperm in rare areas of dilated seminiferous tubules (DSFTs) among the mass of collapsed seminiferous tubules (CSFTs) in men with Klinefelter syndrome (KS) is difficult to explain. Two plausible explanations of sperm production in KS are either spontaneous rescue of 47,XXY and loss of the additional X ch. in some areas of testis, or existence of low grade mosaicism in tissue levels. Our lab has confirmed that all pre-meiotic cells in testis have two X ch. including spermatogonial stem cells (SSCs).
Exogenous testosterone supplementation can be used to treat low testosterone; however, it has several adverse effects including infertility due to negative feedback on the hypothalamic-pituitary-gonadal (HPG) axis. We evaluated the feasibility of subcutaneously autografting Leydig stem cells (LSC) in combination with Sertoli and myoid cells to increase testosterone. Furthermore, we evaluated the mechanism essential for survival of LSC in extra-testicular milieu.
Spermatogonial stem cells (SSCs) function as a life-long spermatogenesis reserve. Self-renewal and stem maintenance are foundational characteristics of SSCs. To maintain these cellular characteristics, the regulation of genome transcription is mandatory, although the basis of this mechanism remains unknown. Recently, small mRNA, called microRNA (miRNA), consisting of 18 –25 nucleotide bases have been recognized as key transcription regulators. The effect involves more than one-third of all transcription regulation.
This article reviews the latest studies on POF to summarize current understanding and future directions.
This study presents a summary of the investigations that indicate the key role of stem cell therapy in regeneration and renovation of defective parts.
Reduced intensity conditioning (RIC) is increasingly used for hematopoietic stem cell transplantation (HCT). Risk of infertility and primary gonadal insufficiency secondary to standard myeloablative (MAC) HCT is high, but little is known of these complications following use of RIC HCT.