The present study examines the existence of clonogenic patterns in the proliferation and differentiation of spermatogonial stem cells in two species of non-human primates, the marmoset and the rhesus monkey. We developed a novel approach to detect proliferating spermatogonial clones in whole mounts of seminiferous tubules. Dual fluorescence labeling of bromodeoxyuridine and acrosin in conjuncti...

Although the contribution of Hedgehog (Hh) signalling to stem cell development and oncogenesis is well recognised, its importance for spermatogonial stem cells (SSCs) has not been established. Here we interrogate adult rat SSCs using an established model in which only undifferentiated spermatogonial cells remain in the testis at 15 weeks following irradiation, and spermatogonial differentiation...

OBJECTIVE We evaluated structural and functional changes of fresh and frozen-thawed adult mouse spermatogonial stem cells following auto-transplantation into gamma-irradiated testes. MATERIALS AND METHODS In this experimental research, the right testes from adult mice (n=25) were collected, then Sertoli and spermatogonial cells were isolated using two-step enzymatic digestion, lectin immobili...

OBJECTIVE(S) Transplantation quality improvement and reduction of cellular damage are important goals that are now considered by researchers. Melatonin is secreted from the pineal gland and some organs such as testes. According to beneficial effects of melatonin (such as its antioxidant and antiapoptotic properties), researchers have proposed that the use of melatonin may improve transplantatio...

BACKGROUND Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis, and reside within a specific microenvironment in the testes called "niche" which regulates stem cell properties, such as, self-renewal, pluripotency, quiescence and their ability to differentiate. METHODOLOGY/PRINCIPAL FINDINGS Here, we introduce zebrafish as a new model for the study of SSCs in vertebrates. Us...

Vaccinia-related kinase 1 (VRK1) is a crucial protein kinase for mitotic regulation. VRK1 is known to play a role in germ cell development, and its deficiency results in sterility. Here we describe that VRK1 is essential for the maintenance of spermatogonial stem cells. To determine whether VRK1 plays a role in these cells, we assessed the population size of undifferentiated spermatogonia. Flow...

objective(s): to investigate the efficacy of interleukin 11 (il-11) towards the high dose methotrexate (hdmtx)-concurrent rat small intestinal mucositis and its impacts on the proliferation of the human t-lymphoblastic leukemia (cem) cell line. materials and methods:95 wistar rats were randomly divided into five groups, the normal control group (a), the methotrexate (mtx) control group (b), the...

background and objective: the management of apoptotic cell death has been considered as a putative therapeutic strategy for cancer treatment. in the present study we investigated the putative pro-apoptotic effect of allicin, the main garlic organosulfur component with repeatedly claimed chemopreventive potency, on the human adenocarcinoma cell line ht29 as an apoptosis resistant cell line, in v...

the cytotoxicity of the biomaterials is a key issue that should be addressed prior to pre-clinical applications. this study was designed to evaluate and compare the cytotoxixity of two forms of bioactive glasses:nanopowder:andmicropowder. human hgf1-pi53 gingival fibroblast cells were used to evaluate the cytotoxicity of 0.5, 1, 1.5, 2, 5, 10, 15 and 20 mg/ml concentrations of the two bioactive...

The complex processes of spermatogenesis are regulated by various factors. The aim of the current study is to determine the effect of epidermal growth factor (EGF) on spermatogonial proliferation and clarify the mechanism causing the proliferation in newt testis. In the organ culture, EGF stimulated spermatogonial proliferation, but not their differentiation into spermatocytes. cDNA cloning ide...