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Barsoum Ivraym B - - 2010
In most eutherian mammals, sexually dimorphic masculinization is established by androgen-producing fetal Leydig cells in the embryonic testis. Fetal Leydig cells, which lack expression of the testis-determining gene SRY, arise after the appearance of SRY-expressing Sertoli cells. Therefore, the appearance and differentiation of fetal Leydig cells are probably regulated by ...
Nel-Themaat Liesl - - 2010
The mammalian testis is a complex organ composed of multiple cell types that are organized into seminiferous tubules and an interstitium, producing spermatozoa and hormones, respectively. During embryogenesis, the testis forms from the genital ridge associated with the embryonic kidney called the mesonephros. After germ cells migrate into the genital ...
Deshpande Shayu - - 2010
Juxtamembrane signaling via the membrane growth factor KitL is critical for Kit mediated functions. KitL has a conserved cytoplasmic domain and has been shown to possess a monomeric leucine-dependent basolateral targeting signal. To investigate the consequences in vivo of impaired basolateral KitL targeting in polarized epithelial cells, we have mutated ...
So Edmund Cheung - - 2010
The peripheral-type benzodiazepine receptor (PBR), a putative receptor in Leydig cells, modulates steroidogenesis. Since benzodiazepines are commonly used in regional anesthesia, their peripheral effects need to be defined. Therefore, this study set out to investigate in vitro effects of the benzodiazepine midazolam (MDZ) on Leydig cell steroidogenesis, and the possible ...
Nalam Roopa L - - 2009
Retinoblastoma protein (RB) plays crucial roles in cell cycle control and cellular differentiation. Specifically, RB impairs the G(1) to S phase transition by acting as a repressor of the E2F family of transcriptional activators while also contributing towards terminal differentiation by modulating the activity of tissue-specific transcription factors. To examine ...
Tanwar Pradeep S - - 2010
Sertoli and germ cell interactions are essential for spermatogenesis and, thus, male fertility. Sertoli cells provide a specialized microenvironment for spermatogonial stem cells to divide, allowing both self-renewal and spermatogenesis. In the present study, we used mice with a conditional activated allele of the beta-catenin gene (Ctnnb1(tm1Mmt)(/+)) in Sertoli cells ...
Nielsen J E - - 2010
The aim of this study was to investigate endothelial lipase (EL, LIPG) and lipoprotein lipase (LPL) mRNA and protein expression in normal human testis and testicular germ cell tumours (GCT). Both EL and LPL were expressed in normal seminiferous tubules and in the interstitial compartment. EL mRNA and protein were ...
Dupont Joëlle - - 2010
Follicle-stimulating hormone (FSH) controls the proliferation and differentiation of Sertoli cells of the testis. FSH binds a G protein-coupled receptor (GPCR) to stimulate downstream effectors of the phosphoinositide-3 kinase (PI3K)-dependent pathway, without enhancing PI3K activity. To clarify this paradox, we explored the activity of phosphatase and tensin homolog deleted in ...
Gassei K - - 2010
Sertoli cells undergo a maturation process during post-natal testicular development that leads to the adult-type Sertoli cell, which is required for spermatogenesis. Understanding Sertoli cell maturation is therefore necessary to gain insight into the underlying causes of impaired spermatogenesis and male infertility. The present study characterized the cellular and molecular ...
Tsikolia Nikoloz - - 2009
The origin of fetal Leydig cells (FLC) and whether they share a common lineage with adult Leydig cells (ALC) is still under debate, and a marker to reliably track and isolate fetal Leydig precursor cells remains to be identified. We analyzed KIT positive (KIT+) cells in gonads from bovine fetuses ...
Nalam Roopa L - - 2010
Testicular cell adhesion molecule 1 (Tcam1) is a testis-expressed gene that is evolutionarily conserved in most mammalian species. The putative location of TCAM1 on the cell surface makes it an attractive contraceptive target to study. We found that Tcam1 transcription is enriched in the adult testis, and in situ hybridization ...
Costa Guilherme M J - - 2010
Although the collared peccary (Tayassu tajacu) is found throughout the Americas, with a high potential for domestication and commercial exploitation, there are few data on the reproductive biology of this mammalian species. The aim of the present study was to investigate testis structure, spermatogenic cycle length, Sertoli cell efficiency, and ...
Mazaud-Guittot S - - 2010
Tissue integrity relies on barriers formed between epithelial cells. In the testis, the barrier is formed at the initiation of puberty by a tight junction complex between adjacent Sertoli cells, thereby defining an adluminal compartment where meiosis and spermiogenesis occur. Claudin 11 is an obligatory protein for tight junction formation ...
Albrecht Martin - - 2009
Human testicular peritubular cells are myofibroblast-like cells that surround the seminiferous tubules and are responsible for tubular contractility and sperm transport. In the last few years, several reports have augmented this simplified view, showing that peritubular cells are not only structural cells but also actively secrete paracrine mediators, thereby influencing ...
Adamopoulos D A - - 2010
Azoospermia can be either of obstructive ctiology or due to the testis' failure to initiate or maintain spermatogenesis. FSH acts through its receptor at Sertoli cell level and modulates spermatogenesis initiation and maintenance. Inhibin B is a Sertoli cell product expressing the functional capacity of the cell and in an ...
Capretto L - - 2010
Polysaccharides (e.g. alginate or agarose) represent a class of polymers commonly employed for the preparation of microparticles for cell entrapment and tissue engineering applications. The present work describes the production and characterization, by a microfluidic approach, of microbeads constituted of alginate and alginate/agarose blends, for the encapsulation of eukaryotic cells. ...
Sarraj Mai A - - 2010
Betaglycan (Tgfbr3) is a coreceptor for transforming growth factor-beta (TGFB) superfamily ligands. In the current study, a defect in seminiferous cord formation was detected in 12.5-13.5 days postcoitum (dpc) beta glycan null murine testis. Immunohistochemistry with antibodies against cell-specific markers revealed defects in somatic cell populations. To confirm these data, ...
Welsh Michelle M MRC Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, Edinburgh EH16 4TJ, - - 2009
Androgens are essential for normal spermatogenesis and male fertility, but how androgens exert this effect remains uncertain. Androgen receptors (ARs) are expressed in several testicular cell types, but continuing uncertainty exists over which cell type mediates androgen control of spermatogenesis. Androgen signaling via Sertoli cells (SCs) is essential for complete ...
Cheng C Yan - - 2010
Spermatogenesis is a complex biochemical event, involving the participation of the hypothalamus and the pituitary gland via secretion of the hypothalamus hormone GnRH, and two pituitary hormones FSH and LH. Thus, the hypothalamic-pituitary-testicular axis is a crucial regulatory axis for testicular function. Recent studies have shown that in the microenvironment ...
Amirzargar Mohammad Ali - - 2009
We aimed to assess the long-term toxic effects of sulphur mustard (SM) on the testis and male fertility two decades after exposure. A historical cohort study was conducted in 2005. Sixty-four SM-exposed and 64 matched SM-unexposed casualties of the Iraq-Iran conflict were enrolled. Fecundity status, semen indices, hormonal assay results ...
de Rooij Dirk G - - 2009
Spermatogonial stem cells (SSCs; A(s) spermatogonia) and their direct descendants (A(pr) and A(al) spermatogonia) are preferentially located in those areas of the seminiferous tubules that border on the interstitial tissue. Fewer of these cells are present in tubule areas directly bordering on another tubule. Therefore, the SSC niche is related ...
Li Michelle W M - - 2009
During spermatogenesis in mammalian testes, junction restructuring takes place at the Sertoli-Sertoli and Sertoli-germ cell interface, which is coupled with germ cell development, such as cell cycle progression, and translocation of the germ cell within the seminiferous epithelium. In the rat testis, restructuring of the blood-testis barrier (BTB) formed between ...
Boekelheide Kim K Brown University, Providence, Rhode Island 02912, USA. - - 2009
Adult male rats gestationally exposed to di(n-butyl)phthalate (DBP) have dysgenetic testes characterized by seminiferous epithelial degeneration, clustering of Leydig cells, and decreased spermatogenesis. Cell proliferation and apoptosis are key processes regulating development of the testis, and alterations in these processes may underlie testicular dysgenesis. To determine whether gestational exposure to ...
Piotrkowski Barbara - - 2009
In the present study, we demonstrate the expression of heme oxygenase (HO) isozymes, HO-1 and HO-2 (listed as HMOX1 and HMOX2 in the MGI Database), in MA-10 Leydig tumor cells and its effect on steroidogenesis. The well-known HO inducer, hemin, increased both HO-1 and HO-2 protein levels and HO-specific activity. ...
Stornelli M A - - 2009
The aim of this study was to asses the variation in the morphology of the seminal epithelium in relation to natural photoperiod in male cats. Tom cats (n = 240) were castrated every other week throughout the year. Each testis was fixed in Bouin's solution and cut into sections. The ...
Kaisman-Elbaz Tehila - - 2009
Sertoli cells, lining the walls of the seminiferous tubules, are in close contact with and regulate all aspects of the development of the germ cells. Clusterin, is a glycoprotein produced abundantly by Sertoli cells, and associated with either apoptosis or cell survival. Zinc is present in high concentrations in the ...
Itman Catherine - - 2009
Activin is required for testis development. Activin signals via phosphorylation and nuclear accumulation of SMAD2 and SMAD3. We present novel findings of developmentally regulated activin signaling leading to specific transcriptional outcomes in testicular Sertoli cells. In immature, proliferating, Sertoli cells, activin A induces nuclear accumulation of SMAD3, but not SMAD2, ...
Iwasaki Yuko - - 2009
Seasonal change in spermatogenesis was examined in the restricted spermatogonium-type testes of a teleost, Oryzias latipes. Histological observation revealed that the number of each stage of germ cells during most of the non-reproductive season, from October to January (O-J period) was nearly half of that during the reproductive season, from ...
Adhikari R C - - 2009
One hundred one azoospermic males were subjected to fine needle aspiration cytology (FNAC) of the testis and 11 of them underwent testicular biopsy as well. In 99 cases, the aspiration was adequate for classifying into different categories, which are as follows: Sertoli cell only syndrome (46), normal spermatogenesis (27), hypospermatogenesis ...
Tang Paisu - - 2011
Mutations in ATRX (alpha-thalassaemia and mental retardation on the X-chromosome) can give rise to ambiguous or female genitalia in XY males, implying a role for ATRX in testicular development. Studies on ATRX have mainly focused on its crucial role in brain development and α-globin regulation; however, little is known about ...
Okada Fatima Kazue - - 2009
Etoposide is a chemotherapeutic agent that induces cell death by blocking topoisomerase II catalytic function. Although etoposide is effective in the treatment of cancer, it also causes the death of normal proliferating cells, including male germ cells. Administration of etoposide during the prepubertal phase causes diturbances in several testicular morphometric ...
Ford J J - - 2009
Meishan boars experience puberty at a younger age than crossbred boars in association with earlier expansion of seminiferous tubules and smaller postpubertal testicular size. The current study defined changes in expression, assessed by immunohistochemistry, of anti-Mullerian hormone (AMH) and CDKN1B, markers of Sertoli cell differentiation, in prepubertal Meishan and crossbred ...
Albrecht Eugene D - - 2009
The foundation for development of the male reproduction system occurs in utero, but relatively little is known about the regulation of primate fetal testis maturation. Our laboratories have shown that estrogen regulates key aspects of the physiology of pregnancy and fetal development. Therefore, in the present study, we characterized and ...
Yao Bing - - 2009
OBJECTIVES: To examine the expression of annexin A5, a recently emerged multifunctional protein, in the testis after experimental cryptorchidism. METHODS: The hemilateral testes of rats were surgically relocated from the scrotum into the abdomen. The annexin A5 content was evaluated by Western blot analysis, and its distribution was determined by ...
Takano Naoharu - - 2009
Mouse Tesspl has been shown to be a testis-specific gene that may contribute to spermatogenesis. In this report, we raised a specific antibody against TESSP1 to assess its biological role. Western blotting detected testicular TESSP1 in all postnatal developmental stages of the mouse. Experiments using the testes of W/W(V) mice, ...
Wu Jiang - - 2009
Nonylphenol (NP) is a common environmental contaminant that is known to disrupt the reproductive system. The testicular Sertoli cells play a pivotal role in the regulation of spermatogenesis and are susceptible to NP-induced reproductive lesions. Our goal was to ascertain whether NP could induce apoptosis in Sertoli cells and to ...
Kohsaka Tetsuya - - 2009
The expression and cellular localization of relaxin and its own receptor, LGR7/RXFP1, were demonstrated in the boar testis, where relaxin was produced by the Leydig cells as 18-kDa pro-relaxin and LGR7/RXFP1 was detected in both Leydig cells and seminiferous epithelial cells, suggesting that a functional relaxin-LGR7/RXFP1 hormone-receptor network operates within ...
Leal Marcelo C - - 2009
The zebrafish has become an important vertebrate model for basic and biomedical research, including the research field of the biology of reproduction. However, very few morphological and stereological data are available regarding zebrafish testis structure and spermatogenesis. In this careful histomorphometric evaluation of the testis, we studied spermatogonial cells using ...
Scott, Hayley M
Disorders of male reproductive health which manifest at birth (cryptorchidism, hypospadias) or in young adulthood (testicular germ cell cancer and low sperm counts), are common and may be increasing in incidence. These disorders have a common fetal origin and share risk factors; consequently they are hypothesized to comprise a testicular ...
Rijntjes Eddy - - 2010
Chronic prenatally induced dietary hypothyroidism delays adult-type Leydig cell development, but does not block this process. Using a chemical model to induce hypothyroidism, it was suggested that development of a new population of Leydig cells was completely inhibited following the addition of the cytotoxic compound ethane-1,2-dimethyl sulphonate (EDS). In this ...
Blanco A - - 2009
Leydig cell morphological changes were evaluated using morphometric and stereological methods in male mice exposed to low doses of cadmium. A possible reversibility of the changes after cadmium withdrawal was also considered. Nuclear morphological parameters and stereological densities of the Leydig cell population were lower in the cadmium-exposed groups than ...
Allan Charles M - - 2009
We have characterized the in vivo actions of human wild-type FSH receptor (FSHR) overexpressed in Sertoli cells of transgenic (Tg) mice (TgFSHRwt) compared with transgenic overexpression of the human activated mutant FSHR*D567G (TgFSHR*D567G). Testicular TgFSHRwt expression significantly elevated specific FSH binding (>2-fold, P < 0.01) relative to nontransgenic testes, similar ...
Lui Wing-Yee - - 2009
Hormones and cytokines are known to regulate cellular functions in all tissues including testis. These two groups of biomolecules exert a broad spectrum of effects on various aspects of spermatogenesis. Among them, one of the regulatory effects on spermatogenesis is to modulate cell junction restructuring between Sertoli cells and between ...
Gong Yong-Guang - - 2009
Leydig cells are the primary source of testosterone in adult males. Recently, a growing body of evidence has shown that testicular innervation functions as a major regulator in Leydig cell steroidogenesis. The question then arises whether this novel regulatory pathway also plays an important role in other biological behaviors of ...
Barsoum Ivraym B - - 2009
Proper cell fate determination in mammalian gonads is critical for the establishment of sexual identity. The Hedgehog (Hh) pathway has been implicated in cell fate decision for various organs, including gonads. Desert Hedgehog (Dhh), one of the three mammalian Hh genes, has been implicated with other genes in the establishment ...
Winnall W R - - 2009
Bacterial lipopolysaccharide increased the production of interleukin 1alpha and activin A, and reduced production of inhibin B, in Sertoli cells from immature male rats measured by enzyme-linked immunosorbent assay (ELISA). The majority of immunoreactive interleukin 1alpha remained within the Sertoli cell, while both activin A and inhibin B were secreted. ...
Shi Yu-Qiang - - 2009
The somatic Sertoli cells play an essential role in testis determination and spermatogenesis by providing nutrition and structural support. In the current study, we report on the novel Ankrd7 gene that contains five ankyrin repeat domains. This gene was specifically expressed in Sertoli cells and was regulated in a maturation-dependent ...
Absalan, Forouzan
Background: In most mammals, the testis is always maintained at a lower temperature than that in the abdomen, and exposure of the testis to body temperature causes degeneration of germ cells. Objective: In this research, the long effect of heat exposure on sperm parameters and microstructure of mouse testis were ...
Chen Haolin - - 2009
Leydig cells are the testosterone-producing cells of the testis. The adult Leydig cell population ultimately develops from undifferentiated mesenchymal-like stem cells present in the interstitial compartment of the neonatal testis. Four distinct stages of adult Leydig cell development have been identified and characterized: stem Leydig cells, progenitor Leydig cells, immature ...
Jewgenow Katarina - - 2009
Teratospermia (>60% morphologically abnormal sperm/ejaculate) is associated with increased sperm output in the domestic cat. The objective of this study was to determine whether increased sperm production in teratospermic donors was associated with disturbances in germ cell apoptosis, the usual mechanism for sperm cell elimination. Apoptosis was measured by evaluating ...
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