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Wang Ruey-Sheng - - 2009
Androgens are critical steroid hormones that determine the expression of the male phenotype, including the outward development of secondary sex characteristics as well as the initiation and maintenance of spermatogenesis. Their actions are mediated by the androgen receptor (AR), a member of the nuclear receptor superfamily. AR functions as a ...
Ahmed Emad A - - 2009
Sertoli cells isolated from the adult mouse and human testis resume proliferation in culture. After 20 days of culture in Dulbecco modified Eagle medium/Ham F12 (DMEM/F12) medium containing 5%% fetal calf serum, about 36%% of the mouse Sertoli cells, identified by their immunohistochemical staining for the Sertoli cell marker vimentin, ...
He Junping - - 2009
The objective of the present studies was to determine the localization of epidermal growth factor (EGF) and the epidermal growth factor receptor (EGFR) in testicular tissue collected from male alpacas at 12 and 24 months of age. In the testes of 12-month-old alpacas, positive staining for EGF was not detected. ...
Gong Yi - - 2009
Nonylphenol (NP) is a widely distributed environment contaminant and has been documented to disrupt testicular development and decrease male fertility. Amongst possible targets of this compound are testicular Sertoli cells, which play a crucial role in supporting and nourishing sperm cells. In the present study, we found that NP treatment ...
Wang Gensheng - - 2009
Testosterone acting through the androgen receptor (AR) maintains the arrest of spermatogonial differentiation in juvenile spermatogonial depletion (jsd mutation in the Utp14b gene) mutant adult male mice. It is not known which of the somatic cell types expressing AR mediates this inhibition. To determine whether Sertoli cells are responsible, we ...
Redenbach, Darlene Marie
During spermatogenesis, spermatogenic cells are moved through the blood testis barrier from the basal to the apical compartment, where they become oriented parallel to the long axis of the Sertoli cell, and situated within Sertoli cell crypts. They are moved again toward the base of the epithelium, before being translocated ...
Perrard Marie-Hélène - - 2009
In co-cultures of pachytene spermatocytes with Sertoli cells, beta-NGF regulates the second meiotic division by blocking secondary spermatocytes in metaphase (metaphase II), and thereby lowers round spermatid formation. In vertebrates, mature oocytes are arrested at metaphase II until fertilization, because of the presence of cytostatic factor (CSF) in their cytoplasm. ...
Carmona Francisco D - - 2009
Some cellular events are crucial in testis organogenesis, including Sertoli and Leydig cell differentiation, mesonephric cell migration and testis cord formation. These processes are controlled by transcription factors, paracrine signalling and hormones. Using the mole species Talpa occidentalis as an alternative animal model, we report the expression patterns of nine ...
Wang Yong - - 2009
BACKGROUND: Apoptosis is important for regulating spermatogenesis. The protein mRHBDD1 (mouse homolog of human RHBDD1)/rRHBDD1 (rat homolog of human RHBDD1) is highly expressed in the testis and is involved in apoptosis of spermatogonia. GC-1, a spermatogonia cell line, has the capacity to differentiate into spermatids within the seminiferous tubules. We ...
Cool Jonah - - 2009
Induction and patterning of the testis occurs over a brief window of time. Before male-specific morphogenesis, the gonad primordium is bipotential and capable of developing into either an ovary or testis. However, expression of the transcription factor SRY initiates male development and induces patterning, proliferation, and epithelialization specific to the ...
Bilinska Barbara - - 2009
The aim of our study was to show whether the cells isolated from testes of patients underwent bilateral orchiectomy for prostatic cancer are able to grown in vitro, and if so, are functionally active. Immuncytochemistry was performed to show the functional status of human cultured cells. In detail, immunolocalization of ...
Davidoff Michail S - - 2009
The Leydig cells of the testis represent the main source of androgens. The idea of Leydig cells as endocrine cells has been the leading characteristic of this interesting cell population till now. Our studies of the last 2 decades allowed us to reveal a new important feature of Leydig cells ...
Sonne Si Brask - - 2009
Microarray and RT-PCR based methods are important tools for analysis of gene expression; however, in tissues containing many different cells types, such as the testis, characterization of gene expression in specific cell types can be severely hampered by noise from other cells. The laser microdissection technology allows for enrichment of ...
Griswold S L SL Program in Developmental Biology, Baylor College of Medicine, Houston, Tex., - - 2009
Male sexual differentiation is a complex process requiring the hormone-producing function of somatic cells in the gonad, including Sertoli cells and fetal Leydig cells (FLCs). FLCs are essential for virilization of the male embryo, but despite their crucial function, relatively little is known about their origins or development. Adult Leydig ...
Nicholls Peter K - - 2009
Oocyte-secreted growth differentiation factor (GDF) 9 and bone morphogenetic protein (BMP) 15 are critical regulatory factors in female reproduction. Together, they promote granulosa cell proliferation and stimulate the maturation of preovulatory follicles. Despite their importance in female fertility, GDF9 and BMP15 expression patterns and function during spermatogenesis have not been ...
Kim Yujin - - 2008
Inhibin, which is important for normal gonadal function, acts on the pituitary gonadotropins to suppress folliclestimulating hormone (FSH) secretion. The level and cellular localization of the inhibin isotypes, alpha, betaA and betaB, in the testis of mice were examined during postnatal development in order to determine if inhibin expression is ...
Papaioannou Marilena D - - 2009
Spermatogenesis requires intact, fully competent Sertoli cells. Here, we investigate the functions of Dicer, an RNaseIII endonuclease required for microRNA and small interfering RNA biogenesis, in mouse Sertoli cell function. We show that selective ablation of Dicer in Sertoli cells leads to infertility due to complete absence of spermatozoa and ...
Walker William H - - 2009
Testosterone is required for the maturation of male germ cells, the production of sperm and thus male fertility. However, the mechanisms by which testosterone regulates spermatogenic processes have not been well defined. In this review, classical and non-classical pathways of testosterone signaling in the Sertoli cells of the testis are ...
Hiramatsu Ryuji - - 2009
In mammals, the Y-linked sex-determining gene Sry cell-autonomously promotes Sertoli cell differentiation from bipotential supporting cell precursors through SRY-box containing gene 9 (Sox9), leading to testis formation. Without Sry action, the supporting cells differentiate into granulosa cells, resulting in ovarian development. However, how Sry acts spatiotemporally to switch supporting cells ...
Yao Pei-Li - - 2009
Mono-(2-ethylhexyl) phthalate (MEHP)-induced Sertoli cell injury in peripubertal rodents results in the stimulation of germ cell apoptosis through an interaction of FAS/FASL between these two cell types. During this peripubertal period, an early spike in the incidence of germ cell apoptosis occurs during the first wave of spermatogenesis and is ...
Rijntjes Eddy - - 2009
Transient hypothyroidism induced by propyl-2-thiouracyl blocks postpartum Leydig cell development. In the present study, the effects of chronic hypothyroidism on the formation of this adult-type Leydig cell population were investigated, using a more physiological approach. Before mating, dams were put on a diet consisting of an iodide-poor feed supplemented with ...
O'Shaughnessy P J - - 2009
Development and maintenance of the male phenotype and establishment of fertility are all dependent upon the activity of the Sertoli cells and Leydig cells of the testis. This review examines the regulation and function of these cell during fetal and post-natal development. Fetal Leydig cells are sensitive to both luteinising ...
Hancock Karen D - - 2009
Testicular Leydig cells express estrogen receptors and are the predominant source of the male sex steroid hormone testosterone (T). Previous studies demonstrated that genistein acts through estrogen receptors in Leydig cells. In the present study, pre-treatment of Leydig cells isolated from 35 day-old male Long Evans rats with the epidermal ...
Maschio L R - - 2010
In spite of widespread application of flutamide in the endocrine therapies of young and adult patients, the side effects of this antiandrogen on spermatogenesis and germ-cell morphology remain unclear. This study evaluates the short-term androgen blockage effect induced by the administration of flutamide to the testes of pubertal (30-day old) ...
Dubey Neelima - - 2009
The present in vitro study for the first time demonstrates the role of extragonadal hormones in regulation of NO production by testicular macrophages in vertebrates and paracrine role of NO in Leydig cell steroidogenesis in fishes. N-nitro L-arginine methyl ester (L-NAME - a NOS inhibitor) treatment substantially reduced NO production ...
Papanastasopoulos Panagiotis - - 2008
SOX-9, an essential factor for male sexual development, can be induced by prostaglandin D2 in a Sry-independent mechanism. Recent data suggest that the hedgehog pathway is involved in the differentiation of normal Sertoli and Leydig cells. The purpose of our study was to investigate the mechanisms involved in the differentiation ...
Oral, Ozlem
Spermatogenesis is a complex process, consisting of highly organized steps controlled by co-action of hormones, such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH), and testicular somatic cells. ln newt testis, FSH stimulates spermatogonial proliferation and differentiation into primary spermatocytes through the receptor expressed on its target somatic cells, namely ...
Galardo María Noel - - 2008
Sertoli cells are necessary to provide adequate levels of lactate for germ cell development. Lactate production is hormonally regulated by follicle-stimulating hormone (FSH) and by a large set of intratesticular regulators such as interleukin-1 beta (IL1 beta) and basic fibroblast growth factor (bFGF). Little is known regarding the critical step ...
Komatsu Tomoko - - 2008
We have indicated the possibility that nanoparticles such as diesel exhaust particles (DEP) and titanium dioxide (TiO(2)) may impair the male mouse reproductive system. In this study, to evaluate the direct effect of nanoparticles on testis-constituent cells, we examined the effect of DEP, TiO(2) and carbon black (CB) on mouse ...
Mondillo Carolina - - 2009
This study was conducted to shed light on the so far unexplored intracellular mechanisms underlying negative modulation of Leydig cell steroidogenesis by histamine (HA). Using the MA-10 cell line and highly purified rat Leydig cells as experimental models, we examined the effect of the amine on biochemical steps known to ...
Wood Michelle A - - 2009
Each Sertoli cell can support a finite number of developing germ cells. During development of the testis, the cessation of Sertoli cell proliferation and the onset of differentiation determine the final number of Sertoli cells and, hence, the number of sperm that can be produced. We hypothesize that the transition ...
Sousa C - - 2008
In testis we find mainly PPP1gamma2 isoform. We hypothesize that in different cell types we can find different regulatory subunits that may constitute targets for therapeutics of diseases such as male infertility, cancer and Alzheimer's disease. We identified a novel alternative splicing isoform of IIIG9 in testis, a known regulator ...
Kostic T S - - 2008
The ability of immobilization stress (IMO) to decrease Leydig cell steroidogenesis and serum androgen concentration has been previously observed, but the possible mechanism(s) involved in the adaptation to prolonged or repeated stress have not been identified. In this study, we investigated whether the Leydig cells obtained from adult rats subjected ...
Mironova Ekaterina - - 2008
Cytoskeletal alterations in both Sertoli cells and germ cells are important during many facets of mammalian spermatogenesis. Diaphanous-related formin proteins are known to control many aspects of actin-based cytoskeletal rearrangements, yet nothing is known regarding the expression of formins in the testis. Accordingly, here we present the first data describing ...
Becker S - - 2008
Semen samples from 60 infertile men were examined by flow cytometry following propidium iodide staining. Of these, 23 samples contained young haploid cells. Transition proteins (TP1 and/or TP2) were detected in 12 of these, using immunohistochemical staining. The presence of TPs in spermatids in semen indicates inhibition in the differentiation ...
Ferreira Adelina - - 2008
The spermatogenesis of Pseudis limellum, from the Southern Pantanal, Brazil, was studied from July 1995 to May 1996, through histological sections of the testis. The cells could be differentiated as: primary spermatogonia, large cells, generally with bilobed nucleus; secondary spermatogonia, smaller cells, with darker cytoplasm, chromatin of radial form; primary ...
Parthasarathy C - - 2008
Clinical and experimental studies have shown the adverse effects of glucocorticoid deficiency/metyrapone treatment on testicular Leydig cell testosterone production. However, molecular mechanisms that underlie the effects of glucocorticoid deficiency on Leydig cell steroidogenesis are not yet determined. Therefore, the present study was designed to assess the mechanism of this phenomenon. ...
Costa G M J - - 2008
The jaguar, like most wild felids, is an endangered species. Since there are few data regarding reproductive biology for this species, our main goal was to investigate basic aspects of the testis and spermatogenesis. Four adult male jaguars were utilized; to determine the duration of spermatogenesis, two animals received an ...
Gassei Kathrin - - 2008
The first morphological sign of testicular differentiation is the formation of testis cords. Prior to cord formation, newly specified Sertoli cells establish adhesive junctions, and condensation of somatic cells along the surface epithelium of the genital ridge occurs. Here, we show that Sertoli cell aggregation is necessary for subsequent testis ...
Martin Luc J - - 2008
It is well established that stress, either physical or psychosocial, causes a decrease in testosterone production by Leydig cells. Glucocorticoids (Gc) are the main mediators of stress response and they convey their repressive effect on Leydig cells through the glucocorticoid receptor (GR). So far, various mechanisms have been proposed to ...
Abu-Zinadah Osama A - - 2008
The testicular histology of the lizard, Uromastyx aegyptius microlepis were varied considerably during hibernation and activity periods, reaching maximum values in summer. The onset of winter induces testicular regression, reduced testis size, testis diameter, diameter and epithelial height of the seminiferous tubules and epididymal epithelial height. Animals exhibit testicular recrudescence ...
Johnston Daniel S - - 2008
Mammalian spermatogenesis is a complex biological process that occurs within a highly organized tissue, the seminiferous epithelium. The coordinated maturation of spermatogonia, spermatocytes, and spermatids suggests the existence of precise programs of gene expression in these cells and in their neighboring somatic Sertoli cells. The objective of this study was ...
Kukucka, Mark A
The 1980's heralded the discovery and identification of extra-pituitary sources of the neurohypophysial hormone oxytocin in non-neural tissues of several animal species. The presence, location and biosynthesis of significant amounts of oxytocin in the ovarian corpus luteum was followed by the immunocytochemical demonstration of an oxytocin-like peptide in the testicular ...
Mutembei H M - - 2009
Oestrogens are essential for male fertility targeting the testicular-epididymal compartment. However, the underlying mechanisms are only vaguely known and species specificities must be considered. The boar has a remarkably high testicular-oestrogen output, with the biologically inactive oestrone-sulphate being the major oestrogen occurring in the testicular vein. In the boar testis ...
Zhang Yun-Hui - - 2008
Phthalates are suspect environmental endocrine disruptors that may affect male reproduction and development by disturbing androgen synthesis and cell-cell interactions in the seminiferous epithelium. The in vivo metabolites, monophthalates, are thought to be the active agents, and toxicant effects including testicular damage and decreased sperm motility have been described previously. ...
Stumpp Taiza - - 2008
Sertoli cells are very important to spermatogenesis homeostasis because they control germ cell proliferation, differentiation, and death. Damages to Sertoli cells cause germ cell death and affect fertility. Etoposide is a potent chemotherapeutic drug largely used against a variety of cancers. However, this drug also kills normal cells, especially those ...
Nimura Masayuki - - 2008
Adrenocorticotropic hormone (ACTH) has been suggested to have possible roles in the fetal testes, one of the organs that express its specific receptors, melanocortin type 2 and 5 receptors (MC2R and MC5R), during the fetal period. We investigated the effect of ACTH on the cells in the testis cord of ...
O'Shaughnessy P J - - 2008
Leydig cells in the rat testis can be specifically ablated with ethane dimethane sulfonate (EDS) and will subsequently re-generate. In this study, we have characterized Leydig cell re-generation and expression of selected cell-signaling molecules in a germ cell-free model of EDS action. This model offers the advantage that re-generation occurs ...
Yao Bing - - 2008
The distribution and regulation of annexin A5 expression, a gonadotropin releasing hormone (GnRH) receptor regulated protein in gonadotropes and luteal cells, in the testes of rats were examined. Immunocytochemical staining revealed high levels of annexin A5 in the Leydig and endothelial cells and lower levels in the primary spermatocytes and ...
Azevedo Maria Helena Ferreira - - 2008
The endocrine portion of mammal testicle is represented by Leydig cells which, together with connective cells, leukocytes, blood and lymphatic vessels, form the intertubular space. The arrangement and proportion of these components vary in the different species of mammals and form mechanisms that keep the testosterone level--the main product of ...
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