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Effect of FSH and insulin on lipogenesis in cultures of Sertoli cells from immature rats

Guma, Fátima Theresinha Costa Rodrigues; Wajner, Moacir; Martini, Lucia Helena; Bernard, Elena Aida
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
66.58%
Follicle-stimulating hormone (FSH) and insulin regulate glycide metabolism in Sertoli cells, thus stimulating lactate production. These stimulatory effects of FSH and insulin do not require protein synthesis, suggesting a modulation of enzyme activity and/or regulation of glucose transport. The present investigation was performed to characterize the hormonal control of lipid metabolism in Sertoli cells. The data indicate that FSH and insulin have a regulatory effect on lipid metabolism in Sertoli cells. After 8 h of preincubation with insulin (5 μg/ml), the activity of the enzyme ATP-citrate lyase in cultured Sertoli cells was increased from 0.19 to 0.34 nmol NAD+ formed μg protein-1 min-1. FSH (100 ng/ml) had no effect on this enzyme. Glycerol phosphate dehydrogenase activity was not affected by any of the hormones tested. When Sertoli cells from 19-day old rats were incubated with [1,2-14C]acetate for 90 or 360 min, the [14C] label was present predominantly in triglyceride and phospholipid fractions with minor amounts in other lipids. In Sertoli cells pretreated for 16 h with insulin and FSH, an increase in acetate incorporation into lipids was observed. Most of the label was in esterified lipids and this percentage increased with the time of treatment; this increase was remarkable in triglycerides of control cells (18.8% to 30.6%). Since Sertoli cell triglycerides participate in the control of spermatogenesis...

Morphometry and morphology of nucleus of the Sertoli and interstitial cells of the tambaqui Colossoma macropomum (Cuvier, 1881) (Pisces: Characidae) during the reproductive cycle

Nakaghi, L. S. O.; Mitsuiki, D.; Santos, H. S. L.; Pacheco, M. R.; Ganeco, Luciana Nakaghi
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: 97-104
ENG
Relevância na Pesquisa
56.54%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Este trabalho permitiu caracterizar a organização estrutural dos testículos de tambaqui Colossoma macropomum, com ênfase às células de Sertoli e intersticiais, bem como analisar morfometricamente o diâmetro dos núcleos das células de Sertoli e a área do tecido intersticial, durante o ciclo reprodutivo. Fragmentos de testículos de tambaqui foram coletados nos seguintes estádios do ciclo reprodutivo: imaturo, repouso, maturação I e II, maduro e regressão, e processados histologicamente. As células de Sertoli se apresentaram na periferia dos cistos de células germinativas, e com o desenvolvimento das mesmas seus núcleos ficavam cada vez menores. As células intersticiais foram melhor evidenciadas entre os lóbulos seminíferos, ao lado de vasos sanguíneos no tecido intersticial dos testículos em maturação.; This study allowed the characterization of the tambaqui Colossoma macropomum testes structural organization, emphasizing Sertoli and interstitial cells and analyzing morphometrically the Sertoli cell nucleus diameter and the interstitial tissue area during the reproductive cycle. Fragments of tambaqui testes were collected in the following reproductive cycle stages: immature...

Morphological changes of Sertoli cells during the male reproductive cycle of the teleost Piaractus mesopotamicus (Holmberg, 1887)

Cruz-Landim, C.; Abdalla, Fábio Camargo; Cruz-Höfling, M. A.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: 241-249
ENG
Relevância na Pesquisa
56.44%
Realizou-se uma investigação das mudanças histológicas e ultra-estruturais das células de Sertoli durante o ciclo reprodutivo de machos de Piaractus mesopotamicus. Os resultados mostraram que o desenvolvimento das células de Sertoli está estritamente relacionado à maturação das células gaméticas. Portanto, as células de Sertoli têm algum papel na maturação das células germinativas durante o ciclo reprodutivo dessa espécie, talvez formando um tecido de sustentação para os cistos espermatogênicos em desenvolvimento, ajudando a reorganização testicular para um novo ciclo reprodutivo, além de outras possíveis funções discutidas no texto.; An investigation of the histological and ultrastructural changes of Sertoli cells during the male reproductive cycle in Piaractus mesopotamicus was made. The results showed that the Sertoli cell development is closely related with germ cell maturation. Therefore, these cells may have some role in germ cell maturation during the reproductive cycle of this species, whether in forming a tissue framework for the developing spermatogenic cysts, aiding in testes reorganization for a new reproductive cycle, in addition to other possible functions discussed in the text.

Testes of Astyanax altiparanae: The Sertoli cell functions in a semicystic spermatogenesis

Costa, F. G.; Adolfi, M. C.; Gomes, C. C.; Jesus, L. W. O.; Batlouni, S. R.; Borella, M. I.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 20-27
ENG
Relevância na Pesquisa
56.51%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); The Astyanax altiparanae (lambari) is a South American freshwater fish belonging to the family Characidae. Although some authors have described reproductive aspects of this species, this is the first study about the morphology of the testes throughout the annual reproductive cycle of A. altiparanae. Fish spermatogenesis differs from that in mammals as it occurs in cysts whose borders are defined by cytoplasmic processes of Sertoli cells, thus creating a favorable environment for spermatogenesis. The functions commonly attributed to fish Sertoli cells were investigated using stereological, light and electron microscopy in A. altiparanae. Results showed that when the Sertoli cells of A. altiparanae are in contact with germ cells, they plan a support function that culminates in the production of spermatozoa. After releasing spermatozoa, modified Sertoli cells form the duct epithelium, transform into secretory cells and release a secretion into the duct lumen where spermatids and sperm are located. Thus, the present study revealed important aspects of the testes of A. altiparanae, and propose a sequence of functions played by the Sertoli cells in this species. (C) 2014 Elsevier Ltd. All rights reserved.

Defining suitable reference genes for RT-qPCR analysis on human sertoli cells after 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure

Ribeiro, Mariana Antunes; Reis, Mariana Bisarro dos; Moraes, Leonardo Nazario de; Briton-Jones, Christine; Rainho, Claudia Aparecida; Scarano, Wellerson Rodrigo
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 7063-7066
ENG
Relevância na Pesquisa
66.25%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 11/04202-1; Processo FAPESP: 12/00253-3; Quantitative real-time RT-PCR (qPCR) has proven to be a valuable molecular technique to quantify gene expression. There are few studies in the literature that describe suitable reference genes to normalize gene expression data. Studies of transcriptionally disruptive toxins, like tetrachlorodibenzo-p-dioxin (TCDD), require careful consideration of reference genes. The present study was designed to validate potential reference genes in human Sertoli cells after exposure to TCDD. 32 candidate reference genes were analyzed to determine their applicability. geNorm and NormFinder softwares were used to obtain an estimation of the expression stability of the 32 genes and to identify the most suitable genes for qPCR data normalization.

Repercussões da obesidade materna e/ou pós-natal sobre as células de Sertoli e a expressão de fatores parácrinos intratesticulares; Repercussions of maternal obesity and/or post natal on the Sertoli cells and the expression of paracrine factors intratesticula

Vanessa Reame
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/03/2015 PT
Relevância na Pesquisa
66.52%
A obesidade está associada a vários prejuízos para a saúde, mas os efeitos sobre o sistema genital e reprodução masculina ainda são pouco compreendidos. Um estudo concluído recentemente em nosso laboratório comparou os efeitos do ambiente obesogênico (AO) em diferentes fases do desenvolvimento de ratos sobre a produção espermática na idade adulta. Todos os grupos expostos ao AO apresentaram prejuízos espermáticos. Para esclarecer esses achados, no presente trabalho, nós investigamos se os diferentes períodos de exposição ao AO resultaram em alterações funcionais nas células de Sertoli e modificaram permanentemente o ambiente parácrino intratesticular. Foram utilizados ratos Wistar adultos expostos à obesidade materna na gestação (O1), na gestação/ lactação (O2), ou sujeitos ao AO após desmame (O3), da lactação até a idade adulta (O4) ou da gestação até a idade adulta (O5) e grupo controle (C). A obesidade materna ou o AO foram induzidos por dieta com 20% de lipídeos (ração controle: 4% de lipídeos), por 15 semanas. As análises em microscopia de luz não mostraram alterações morfológicas nas células de Sertoli e no número dessas células expressando o receptor de andrógeno nos estágios VII e VIII do ciclo do epitélio seminífero. Entretanto...

Hormonal regulation of lactate production and NHE3 expression by Sertoli cells ex vivo : possible roles for sex steroids hormones in spermatogenesis?

Rato, Luis Pedro Ferreira
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2010 ENG
Relevância na Pesquisa
56.64%
Sertoli cells cells play a key role on the establishment of an adequate luminal environment in the seminiferous tubules of the male reproductive tract. The secretion of the seminiferous tubular fluid (STF), as well as, the control of the pH of this fluid is crucial for male fertility. Sertoli cells express various types of ion membrane transporters that are directly involved on the movement basic and acidic particles across the membrane. Among them, is Na+/H+ exchanger (NHE3), which belongs to the Na+/H+ exchanger family, one of the most relevant epithelial ion transporter families, catalyzes the electroneutral transport of extracellular Na+ for intracellular H+. Several authors have provided confirmation that estrogens and androgens play an important role in male fertility, and regulate fluid transport on the male reproductive tract. On the other hand, as germ cells are unable to use glucose for their energy metabolism (Sertoli cells metabolize glucose and the majority of it is converted to lactate, which is preferentially used by developing germ cells). There is a growing awareness that androgens and estrogens have general metabolic roles that reach far beyond reproductive processes. Thus, is important to understand the role of the sex steroids in expression of NHE3 in Sertoli cells...

Effect of FSH and insulin on lipogenesis in cultures of Sertoli cells from immature rats

Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/1997 EN
Relevância na Pesquisa
66.57%
Follicle-stimulating hormone (FSH) and insulin regulate glycide metabolism in Sertoli cells, thus stimulating lactate production. These stimulatory effects of FSH and insulin do not require protein synthesis, suggesting a modulation of enzyme activity and/or regulation of glucose transport. The present investigation was performed to characterize the hormonal control of lipid metabolism in Sertoli cells. The data indicate that FSH and insulin have a regulatory effect on lipid metabolism in Sertoli cells. After 8 h of preincubation with insulin (5 µg/ml), the activity of the enzyme ATP-citrate lyase in cultured Sertoli cells was increased from 0.19 to 0.34 nmol NAD+ formed µg protein-1 min-1. FSH (100 ng/ml) had no effect on this enzyme. Glycerol phosphate dehydrogenase activity was not affected by any of the hormones tested. When Sertoli cells from 19-day old rats were incubated with [1,2­14C]acetate for 90 or 360 min, the [14C] label was present predominantly in triglyceride and phospholipid fractions with minor amounts in other lipids. In Sertoli cells pretreated for 16 h with insulin and FSH, an increase in acetate incorporation into lipids was observed. Most of the label was in esterified lipids and this percentage increased with the time of treatment; this increase was remarkable in triglycerides of control cells (18.8% to 30.6%). Since Sertoli cell triglycerides participate in the control of spermatogenesis...

Morphometry and morphology of nucleus of the Sertoli and interstitial cells of the tambaqui Colossoma macropomum (Cuvier, 1881) (Pisces: Characidae) during the reproductive cycle

Nakaghi,L. S. O.; Mitsuiki,D.; Santos,H. S. L.; Pacheco,M. R.; Ganeco,L. N.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2003 EN
Relevância na Pesquisa
56.44%
This study allowed the characterization of the tambaqui Colossoma macropomum testes structural organization, emphasizing Sertoli and interstitial cells and analyzing morphometrically the Sertoli cell nucleus diameter and the interstitial tissue area during the reproductive cycle. Fragments of tambaqui testes were collected in the following reproductive cycle stages: immature, resting, maturation I and II, mature, and regression, and were histologically processed. The Sertoli cells were found at the periphery of the cysts of germinative lineage cells and the nuclei were shown to be smaller as these cells developed. The interstitial cells were better observed between the seminiferous lobules next to vessels in the interstitial tissue of maturing testes.

Growth Differentiation Factor 9 Is a Germ Cell Regulator of Sertoli Cell Function

Nicholls, P.; Harrison, C.; Gilchrist, R.; Farnworth, P.; Stanton, P.
Fonte: Endocrine Soc Publicador: Endocrine Soc
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
56.46%
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 investigated. In this study we show that the expression and stage-specific localization of both factors are limited to the germ cells of the rat seminiferous epithelium, with GDF9 being principally localized in round spermatids and BMP15 in gonocytes and pachytene spermatocytes. To identify potential cellular targets for GDF9 actions, cells of the seminiferous tubule were isolated and screened for the expression of signaling receptors [activin-like kinase (ALK) 5, ALK6, and BMP receptor, type II)]. Individual receptor types were expressed throughout the seminiferous epithelium, but coexpression of ALK5 and BMP receptor, type II was limited to Sertoli cells and round spermatids. Based on the reproductive actions of related TGFbeta ligands in the ovary and testis, GDF9 was assessed for its ability to regulate tight junction function and inhibin B production in rat Sertoli cell cultures. When recombinant mouse GDF9 was added to immature Sertoli cell cultures...

The enhancement of neural stem cell survival and growth by coculturing with expanded sertoli cells in vitro

Shi, B.; Deng, L.; Shi, X.; Dai, S.; Zhang, H.; Wang, Y.; Bi, J.; Guo, M.
Fonte: Amer Chemical Soc Publicador: Amer Chemical Soc
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
66.39%
Sertoli cells (SCs) have been described as the "nurse cells" of testis to provide essential growth factors and to create a proper environment for the development of other cells (e.g., germinal and neural stem cell). However, the physiological functions of the SCs obtained from different culture conditions are different in a coculturing system, and thus the optimal SC culturing condition should be investigated in vitro. In this paper, primary Sertoli cells were isolated from a 12-day-old mouse and expanded in two different culture conditions: a two dimensional (2D) plastic tissue disc and a three dimensional (3D) microcarrier culture system. They were then cocultured with neural stem cells (NSCs) isolated from 14-day-old mouse embryos. The metabolic activities of SCs(2D) (SCs in 2D) and SCs(3D) (SCs in 3D) and the amount of proteins secreted from two culturing systems were compared. The results show that the metabolic activity and the amount of secreted proteins from SCs(3D) were higher than both from SCs(2D). Three coculturing groups: NSCs+SC(2D), NSCs+SC(3D), and NSCs +SC-conditioned medium (SCCM, control group) were also compared regarding cell morphology and the numbers of neurons, neural outgrowths and neurospheres. The quantity of neurons...

A survey of Sertoli cell differentiation in men after gonadotropin suppression and in testicular cancer

Tarulli, G.A.; Stanton, P.G.; Loveland, K.L.; Rajpert-De Meyts, E.; McLachlan, R.I.; Meachem, S.J.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
56.59%
It is widely held that the somatic cell population that is responsible for sperm development and output (Sertoli cells) is terminally differentiated and unmodifiable in adults. It is postulated, with little evidence, that Sertoli cells are not terminally differentiated in some phenotypes of infertility and testicular cancer. This study sought to compare markers of Sertoli cell differentiation in normospermic men, oligospermic men (undergoing gonadotropin suppression) and testicular carcinoma in situ (CIS) and seminoma samples. Confocal microscopy was used to assess the expression of markers of proliferation (PCNA and Ki67) and functional differentiation (androgen receptor). As additional markers of differentiation, the organization of Sertoli cell tight junction and associated proteins were assessed in specimens with carcinoma in situ. In normal men, Sertoli cells exhibited a differentiated phenotype (i.e., PCNA and Ki67 negative, androgen 40 receptor positive). However, after long-term gonadotropin suppression, 1.7 ± 0.6% of Sertoli cells exhibited PCNA reactivity associated with a diminished immunoreactivity in androgen receptor, suggesting an undifferentiated phenotype. Ki67-positive Sertoli cells were also observed. PCNA-positive Sertoli cells were never observed in tubules with carcinoma in situ...

Molecular role of sulfated glycoprotein-1 (SGP-I/Prosaposin) in Sertoli cells

Morales, C.R.; El-Alfy, M.; Zhao, Q.; Igdoura, S.
Fonte: Murcia : F. Hernández Publicador: Murcia : F. Hernández
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
56.44%
Sulfated Glycoprotein- 1 (SGP- 1) is a major polypeptide secreted by rat Sertoli cells. Sequence analysis revealed a 70% sequence similarity with human prosaposin and a 80% similarity with mouse prosaposin. Both human and mouse prosaposin are 65-70 kDa proteins cleaved in the lysosomes into four 10-15 kDa proteins designated saposins A, B, C and D. Lysosomal saposins function as enzymatic activators that promote the hydrolysis of certain glycolipids. SGP-1 (70 kDa) was first considered as being exclusively secreted to the extracellular space. However, recent immunocytochemical studies using an anti SGP-1 antibody demonstrated the presence of this protein in Sertoli cell lysosomes. In addition Sertoli cell lysosomes isolated by cellular fractionation were found to contain a 65 kDa form of SGP-1 or lysosomal prosaposin, as well as, the 15 kDa saposins. Morphological and immunocytochemical evidences also indicated that both prosaposin and saposins may reach Sertoli cell phagosomes by lysosomal fusion. These phagosomes contain cytoplasmic residual bodies detached from spermatids during spermiation. Thus, prosaposin and their derived saposins must play a role in the hydrolysis of membrane glycolipids present in phagocytosed residual bodies. On the other hand...

Endocrine and paracrine regulation of zebrafish spermatogenesis: the Sertoli cell perspective

Schulz, Rüdiger W.; Nobrega, Rafael Henrique; Morais, Roberto Daltro Vidal de Souza; Waal, Paul P. de; França, Luiz Renato de; Bogerd, Jan
Fonte: Brazilian Coll Animal Reproduction Publicador: Brazilian Coll Animal Reproduction
Tipo: Artigo de Revista Científica Formato: 81-87
ENG
Relevância na Pesquisa
56.5%
Spermatogonial stem cells (SSCs) either self-renew or differentiate into spermatogonia that further develop into spermatozoa. Self-renewal occurs when residing in a specific micro-environment (niche) while displacement from the niche would tip the signalling balance towards differentiation. Considering the cystic type of spermatogenesis in fish, the SSC candidates are single type A undifferentiated (A(und)) spermatogonia, enveloped by mostly one niche-forming Sertoli cell. When going through a self-renewal cell cycle, the resulting new single type Aund spermatogonium would have to recruit another Sertoli cell to expand the niche space, while a differentiating germ cell cyle would result in a pair of spermatogonia that remain in contact with their cyst-forming Sertoli cells. In zebrafish, thyroid hormone stimulates the proliferation of Sertoli cells and of type Aund spermatogonia, involving Igf3, a new member of the Igf family. In cystic spermatogenesis, type Aund spermatogonia usually do not leave the niche, so that supposedly the signalling in the niche changes when switching from self-renewal to differentiation. and rzAmh inhibited differentiation of type A(und) spermatogonia as well as Fsh-stimulated steroidogenesis. Thus, for Fsh to efficiently stimulate testis functions...

Is the adult sertoli cell terminally differentiated?

Tarulli, G.A.; Stanton, P.G.; Meachem, S.J.
Fonte: Society for the Study of Reproduction Publicador: Society for the Study of Reproduction
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
56.55%
New data have challenged the convention that the adult Sertoli cell population is fixed and unmodifiable. The Sertoli cell has two distinct functions: 1) formation of the seminiferous cords and 2) provision of nutritional and structural support to developing germ cells. For these to occur successfully, Sertoli cells must undergo many maturational changes between fetal and adult life, the main switches occurring around puberty, including the loss of proliferative activity and the formation of the blood-testis barrier. Follicle-stimulating hormone plays a key role in promoting Sertoli cell proliferation, while thyroid hormone inhibits proliferative activity in early postnatal life. Together these regulate the Sertoli-germ cell complement and sperm output in adulthood. By puberty, the Sertoli cell population is considered to be stable and unmodifiable by hormones. But there is mounting evidence that the size of the adult Sertoli cell population and its maturational status is modifiable by hormones and that Sertoli cells can gain proliferative ability in the spermatogenically disrupted hamster and human model. This new information demonstrates that the adult Sertoli cell population, at least in the settings of testicular regression in the hamster and impaired fertility in humans in vivo and from mice and men in vitro...

Expansion of mouse sertoli cells on microcarriers

Shi, B.; Zhang, S.; Wang, Y.; Zhuang, Y.; Chu, J.; Zhang, S.; Shi, X.; Bi, J.; Guo, M.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
66.32%
BACKGROUND: Sertoli cells (SCs) have been described as the 'nurse cells' of the testis whose primary function is to provide essential growth factors and create an appropriate environment for development of other cells [for example, germinal and nerve stem cells (NSCs), used here]. However, the greatest challenge at present is that it is difficult to obtain sufficient SCs of normal physiological function for cell transplantation and biological medicine, largely due to traditional static culture parameter difficult to be monitored and scaled up. OBJECTIVE: Operational stirred culture conditions for in vitro expansion and differentiation of SCs need to be optimized for large-scale culture. MATERIALS AND METHODS: In this study, the culturing process for primary SC expansion and maintaining lack of differentiation was optimized for the first time, by using microcarrier bead technology in spinner flask culture. Effects of various feeding/refreshing regimes, stirring speeds, seed inoculum levels of SCs, and concentrations of microcarrier used for expansion of mouse SCs were also explored. In addition, pH, osmotic pressure and metabolic variables including consumption rates of glucose, glutamine, amino acids, and formation rates of lactic acid and ammonia...

Hormonal regulation of lactate production and NHE3 expression by Sertoli cells ex vivo : possible roles for sex steroids hormones in spermatogenesis?; Regulação hormonal da produção de lactato e expressão do NHE3 pelas células de Sertoli ex vivo

Rato, Luis Pedro Ferreira
Fonte: Universidade da Beira Interior Publicador: Universidade da Beira Interior
Tipo: Dissertação de Mestrado
Publicado em //2010 ENG
Relevância na Pesquisa
56.65%
Sertoli cells cells play a key role on the establishment of an adequate luminal environment in the seminiferous tubules of the male reproductive tract. The secretion of the seminiferous tubular fluid (STF), as well as, the control of the pH of this fluid is crucial for male fertility. Sertoli cells express various types of ion membrane transporters that are directly involved on the movement basic and acidic particles across the membrane. Among them, is Na+/H+ exchanger (NHE3), which belongs to the Na+/H+ exchanger family, one of the most relevant epithelial ion transporter families, catalyzes the electroneutral transport of extracellular Na+ for intracellular H+. Several authors have provided confirmation that estrogens and androgens play an important role in male fertility, and regulate fluid transport on the male reproductive tract. On the other hand, as germ cells are unable to use glucose for their energy metabolism (Sertoli cells metabolize glucose and the majority of it is converted to lactate, which is preferentially used by developing germ cells). There is a growing awareness that androgens and estrogens have general metabolic roles that reach far beyond reproductive processes. Thus, is important to understand the role of the sex steroids in expression of NHE3 in Sertoli cells...

Ectonucleotidase activities in Sertoli cells from immature rats

Casali, Emerson Andre; Silva, Tiago Rodrigues da; Gelain, Daniel Pens; Kaiser, Glória Regina Rodrigues de Freitas; Battastini, Ana Maria Oliveira; Sarkis, João José Freitas; Bernard, Elena Aida
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
66.47%
Sertoli cells have been shown to be targets for extracellular purines such as ATP and adenosine. These purines evoke responses in Sertoli cells through two subtypes of purinoreceptors, P2Y2 and PA1. The signals to purinoreceptors are usually terminated by the action of ectonucleotidases. To demonstrate these enzymatic activities, we cultured rat Sertoli cells for four days and then used them for different assays. ATP, ADP and AMP hydrolysis was estimated by measuring the Pi released using a colorimetric method. Adenosine deaminase activity (EC 3.5.4.4) was determined by HPLC. The cells were not disrupted after 40 min of incubation and the enzymatic activities were considered to be ectocellularly localized. ATP and ADP hydrolysis was markedly increased by the addition of divalent cations to the reaction medium. A competition plot demonstrated that only one enzymatic site is responsible for the hydrolysis of ATP and ADP. This result indicates that the enzyme that acts on the degradation of tri- and diphosphate nucleosides on the surface of Sertoli cells is a true ATP diphosphohydrolase (EC 3.6.1.5) (specific activities of 113 ± 6 and 21 ± 2 nmol Pi mg-1 min-1 for ATP and ADP, respectively). The ecto-5'- nucleotidase (EC 3.1.3.5) and ectoadenosine deaminase activities (specific activities of 32 ± 2 nmol Pi mg-1 min-1 for AMP and 1.52 ± 0.13 nmol adenosine mg-1 min-1...

Ectonucleotidase activities in Sertoli cells from immature rats

Casali,E.A.; Silva,T.R. da; Gelain,D.P.; Kaiser,G.R.R.F.; Battastini,A.M.O.; Sarkis,J.J.F.; Bernard,E.A.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2001 EN
Relevância na Pesquisa
66.47%
Sertoli cells have been shown to be targets for extracellular purines such as ATP and adenosine. These purines evoke responses in Sertoli cells through two subtypes of purinoreceptors, P2Y2 and P A1. The signals to purinoreceptors are usually terminated by the action of ectonucleotidases. To demonstrate these enzymatic activities, we cultured rat Sertoli cells for four days and then used them for different assays. ATP, ADP and AMP hydrolysis was estimated by measuring the Pi released using a colorimetric method. Adenosine deaminase activity (EC 3.5.4.4) was determined by HPLC. The cells were not disrupted after 40 min of incubation and the enzymatic activities were considered to be ectocellularly localized. ATP and ADP hydrolysis was markedly increased by the addition of divalent cations to the reaction medium. A competition plot demonstrated that only one enzymatic site is responsible for the hydrolysis of ATP and ADP. This result indicates that the enzyme that acts on the degradation of tri- and diphosphate nucleosides on the surface of Sertoli cells is a true ATP diphosphohydrolase (EC 3.6.1.5) (specific activities of 113 ± 6 and 21 ± 2 nmol Pi mg-1 min-1 for ATP and ADP, respectively). The ecto-5'-nucleotidase (EC 3.1.3.5) and ectoadenosine deaminase activities (specific activities of 32 ± 2 nmol Pi mg-1 min-1 for AMP and 1.52 ± 0.13 nmol adenosine mg-1 min-1...

Gene silencing by RNAi in mouse Sertoli cells

González-González, Emilio; López-Casas, Pedro P.; Del Mazo, Jesús
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artículo Formato: 546185 bytes; application/pdf
ENG
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9 pages, 5 figures.-- PMCID: PMC2483279.; [Background] RNA interference (RNAi) is a valuable tool in the investigation of gene function. The purpose of this study was to examine the availability, target cell types and efficiency of RNAi in the mouse seminiferous epithelium.; [Methods] The experimental model was based on transgenic mice expressing EGFP (enhanced green fluorescent protein). RNAi was induced by in vivo transfection of plasmid vectors encoding for short hairpin RNAs (shRNAs) targeting EGFP. shRNAs were transfected in vivo by microinjection into the seminiferous tubules via the rete testis followed by square wave electroporation. As a transfection reporter, expression of red fluorescent protein (HcRed 1) was used. Cell types, the efficiency of both transfections and RNAi were all evaluated.; [Results] Sertoli cells were the main transfected cells. A reduction of about 40% in the level of EGFP protein was detected in cells successfully transfected both in vivo and in vitro. However, the efficiency of in vivo transfection was low.; [Conclusion] In adult seminiferous epithelial cells, in vivo post-transcriptional gene silencing mediated by RNAi via shRNA is efficient in Sertoli cells. Similar levels of RNAi were detected both in vivo and in vitro. This also indicates that Sertoli cells have the necessary silencing machinery to repress the expression of endogenous genes via RNAi.; This work was supported by grant from the MEC (BFU2004-03977) and the MSC (FIS PI071007).; Peer reviewed