in this review, we aim to examine the effect of extrinsic and intrinsic factors on spermatogenesis process taking into account a complex signaling pathway. primarily, it is suggested that retinoic acid (ra) has a vital function in spermatogenesis process and it is considered to be essential for completion of spermatogonia into mature spermatozoa. in the present review, the key effects of retino...

Within the testis, Sertoli-cell is the primary target of pituitary FSH. Several growth factors have been described to be produced specifically by Sertoli cells and modulate male germ cell development through paracrine mechanisms. Some have been shown to act directly on spermatogonia such as GDNF, which acts on self-renewal of spermatogonial stem cells (SSCs) while inhibiting their differentiati...

It is well established that the c-kit gene plays an essential role in the proliferation of differentiating spermatogonia in prepuberal mice. However, the mechanisms that regulate the onset of spermatogenesis, i.e. differentiation of spermatogonial stem cells and c-kit expression, are poorly understood. Here we identify a novel signal transduction system in mouse prepuberal testis regulating thi...

Spermatogenesis is sustained by the proliferation and differentiation of spermatogonial stem cells (SSCs). However, the molecules controlling these processes remain largely unknown. Here, we developed a simplified high concentration serum-containing system for the culture of mouse SSCs. Analysis of SSCs markers and transplantation results revealed that the cultured spermatogonia retained stem c...

INTRODUCTION Male fertility requires continual spermatogenesis, a process dependent on activities of an undifferentiated spermatogonial population composed of spermatogonial stem cells (SSCs) and transient amplifying progenitor spermatogonia (de Rooij and Russell, 2000; Oatley and Brinster, 2012). Self-renewal of SSCs maintains a constant pool from which progenitors will arise and amplify in nu...

Like stem cells in other tissues, spermatogonia, including spermatogonial stem cells (SSCs) at the foundation of differentiation hierarchy, undergo age-related decline in function. The promyelocytic leukemia zinc finger (Plzf) protein plays an essential role in spermatogonia maintenance by preventing their differentiation. To evaluate whether there is an age-related change in Plzf expression, w...

This study aimed to provide a molecular signature for enriched adult human stem/progenitor spermatogonia during short-term (<2 weeks) and long-term culture (up to more than 14 months) in comparison to human testicular fibroblasts and human embryonic stem cells. Human spermatogonia were isolated by CD49f magnetic activated cell sorting and collagen(-)/laminin(+) matrix binding from primary testi...

The H2-receptor antagonist cimetidine is an antiulcer drug also used for the treatment of cancer due to its antiangiogenic effect. However, this drug has caused structural changes in the seminiferous tubules. Vitamin B12 has been used as a therapeutic agent for the treatment of male infertility. The supplementation of rats with vitamin B12 during cimetidine treatment has recovered the damaged s...

Human spermatogenic cells have not yet been isolated, and notably, their global miRNA profiles remain unknown. Here we have effectively isolated human spermatogonia, pachytene spermatocytes and round spermatids using STA-PUT velocity sedimentation. RT-PCR, immunocytochemistry and meiosis spread assays revealed that the purities of isolated human spermatogonia, pachytene spermatocytes, and round...