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Pesquisa : G08.686.784.277.760 [Categoria DeCS]
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[PMID]:29307525
[Au] Autor:Candenas L; Pinto FM; Cejudo-Román A; González-Ravina C; Fernández-Sánchez M; Pérez-Hernández N; Irazusta J; Subirán N
[Ad] Endereço:Instituto de Investigaciones Químicas (L.C., F.M.P., A.C.-R., N.P.), CSIC, Seville, Spain. Electronic address: luzcandenas@iiq.csic.es.
[Ti] Título:Veratridine-sensitive Na channels regulate human sperm fertilization capacity.
[So] Source:Life Sci;196:48-55, 2018 Mar 01.
[Is] ISSN:1879-0631
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:AIMS: The sperm plasma membrane contains specific ion channels and transporters that initiate changes in Ca , Na , K and H ions in the sperm cytoplasm. Ion channels are key regulators of the sperm membrane potential, cytoplasmic Ca and intracellular pH (pH ), which leads to regulate motility, capacitation, acrosome reaction and other physiological processes crucial for successful fertilization. Expression of epithelial sodium channels (ENaC) and voltage-gated sodium channels (Na ) in human spermatozoa has been reported, but the role of Na fluxes sodium channels in the regulation of sperm cell function remains poorly understood. In this context, we aimed to analyze the physiological role of Na channels in human sperm. MAIN METHODS: Motility and hyperactivation analysis was conducted by CASA analysis. Flow cytometry and spectrophotometry approaches were carried out to measure Capacitation, Acrosome reaction, immunohistochemistry for Tyr-residues phosporylation, [Ca ] levels and membrane potential. KEY FINDINGS: Functional studies showed that veratridine, a voltage-gated sodium channel activator, increased sperm progressive motility without producing hyperactivation while the Na antagonist lidocaine did induce hyperactivated motility. Veratridine increased protein tyrosine phosphorylation, an event occurring during capacitation, and its effects were inhibited in the presence of lidocaine and tetrodotoxin. Veratridine had no effect on the acrosome reaction by itself, but was able to block the progesterone-induced acrosome reaction. Moreover, veratridine caused a membrane depolarization and modified the effect of progesterone on [Ca ] and sperm membrane potential. SIGNIFICANCE: Our results suggest that veratridine-sensitive Na channels are involved on human sperm fertility acquisition regulating motility, capacitation and the progesterone-induced acrosome reaction in human sperm.
[Mh] Termos MeSH primário: Fertilização/efeitos dos fármacos
Agonistas de Canais de Sódio/farmacologia
Canais de Sódio/efeitos dos fármacos
Espermatozoides/efeitos dos fármacos
Veratridina/farmacologia
[Mh] Termos MeSH secundário: Reação Acrossômica/efeitos dos fármacos
Adolescente
Adulto
Feminino
Seres Humanos
Imuno-Histoquímica
Técnicas In Vitro
Lidocaína/farmacologia
Masculino
Potenciais da Membrana/efeitos dos fármacos
Progesterona/antagonistas & inibidores
Progesterona/farmacologia
Receptores Androgênicos/efeitos dos fármacos
Sêmen/efeitos dos fármacos
Sódio/metabolismo
Bloqueadores dos Canais de Sódio/farmacologia
Capacitação Espermática/efeitos dos fármacos
Motilidade Espermática/efeitos dos fármacos
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Receptors, Androgen); 0 (Sodium Channel Agonists); 0 (Sodium Channel Blockers); 0 (Sodium Channels); 4G7DS2Q64Y (Progesterone); 71-62-5 (Veratridine); 98PI200987 (Lidocaine); 9NEZ333N27 (Sodium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180109
[St] Status:MEDLINE


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[PMID]:29061915
[Au] Autor:Nomikos M; Kashir J; Lai FA
[Ad] Endereço:College of Medicine, Member of QU Health, Qatar University, PO Box 2713, Doha, Qatar mixosn@yahoo.com.
[Ti] Título:The role and mechanism of action of sperm PLC-zeta in mammalian fertilisation.
[So] Source:Biochem J;474(21):3659-3673, 2017 Oct 23.
[Is] ISSN:1470-8728
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:At mammalian fertilisation, the fundamental stimulus that triggers oocyte (egg) activation and initiation of early embryonic development is an acute rise of the intracellular-free calcium (Ca ) concentration inside the egg cytoplasm. This essential Ca increase comprises a characteristic series of repetitive Ca oscillations, starting soon after sperm-egg fusion. Over the last 15 years, accumulating scientific and clinical evidence supports the notion that the physiological stimulus that precedes the cytosolic Ca oscillations is a novel, testis-specific phospholipase C (PLC) isoform, known as PLC-zeta (PLCζ). Sperm PLCζ catalyses the hydrolysis of phosphatidylinositol 4,5-bisphosphate triggering cytosolic Ca oscillations through the inositol 1,4,5-trisphosphate signalling pathway. PLCζ is the smallest known mammalian PLC isoform with the most elementary domain organisation. However, relative to somatic PLCs, the PLCζ isoform possesses a unique potency in stimulating Ca oscillations in eggs that is attributed to its novel biochemical characteristics. In this review, we discuss the latest developments that have begun to unravel the vital role of PLCζ at mammalian fertilisation and decipher its unique mechanism of action within the fertilising egg. We also postulate the significant potential diagnostic and therapeutic capacity of PLCζ in alleviating certain types of male infertility.
[Mh] Termos MeSH primário: Sinalização do Cálcio/fisiologia
Fosfoinositídeo Fosfolipase C/metabolismo
Capacitação Espermática/fisiologia
Interações Espermatozoide-Óvulo/fisiologia
Espermatozoides/enzimologia
[Mh] Termos MeSH secundário: Animais
Feminino
Seres Humanos
Infertilidade Masculina/enzimologia
Infertilidade Masculina/genética
Isoenzimas/genética
Isoenzimas/metabolismo
Masculino
Fosfoinositídeo Fosfolipase C/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Isoenzymes); EC 3.1.4.11 (PLCZ1 protein, human); EC 3.1.4.11 (Phosphoinositide Phospholipase C)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171027
[Lr] Data última revisão:
171027
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171025
[St] Status:MEDLINE
[do] DOI:10.1042/BCJ20160521


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[PMID]:28638922
[Au] Autor:Li R; Li K; Yang Y; Sun PB; Chen AJ; Ni Y
[Ad] Endereço:School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou 325035, China.
[Ti] Título:[Palmitoylation of heat shock protein 90 in mouse sperm].
[So] Source:Sheng Li Xue Bao;69(3):298-304, 2017 Jun 25.
[Is] ISSN:0371-0874
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:Protein palmitoylation, one of post-translation modifications, refers to the addition of saturated 16-carbon palmitic acid to cysteine residues via the thioester bond. It plays key roles in various functional activities, such as the interaction, stability and location of proteins. Heat shock protein 90 (Hsp90), an important molecular chaperone, has been reported to be involved in sperm capacitation. However, it remains unclear whether protein palmitoylation exists in sperm and whether Hsp90 in sperm is palmitoylated under different physiological conditions. In this study, we examined whether the protein palmitoylation is present in mouse cauda epididymis sperm using acyl-biotin exchange method, predicted the potential palmitoylated sites of Hsp90 by the software CSS-Palm 4.0 and detected the palmitoylated Hsp90 in the mouse sperm from caput epididymis and cauda epididymis by immunoprecipitation. We found that some proteins, approximately 50, 65, 72, 85 and 130 kDa, were palmitoylated in mouse cauda epididymis sperm. Five sites in two Hsp90 isoforms were predicted to be palmitoylated. The results also showed that Hsp90 in mouse sperm was palmitoylated and its palmitoylation level was involved in different physiological conditions: the palmitoylation level of cauda epididymis sperm was higher than that of caput epididymis sperm; and the palmitoylation level after capacitation was much higher than that before capacitation. In conclusion, this study reveals that protein palmitoylation is present in mouse sperm and the palmitoylated Hsp90 is associated with different physiological conditions in sperm.
[Mh] Termos MeSH primário: Proteínas de Choque Térmico HSP90/metabolismo
Ácido Palmítico/química
Espermatozoides/metabolismo
[Mh] Termos MeSH secundário: Animais
Epididimo
Lipoilação
Masculino
Camundongos
Capacitação Espermática
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (HSP90 Heat-Shock Proteins); 2V16EO95H1 (Palmitic Acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171003
[Lr] Data última revisão:
171003
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE


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[PMID]:28472624
[Au] Autor:Baek S; Lee ST; Hwang JY; Park KH; Yun JI
[Ad] Endereço:Department of Animal Life Science, Kangwon National University, Chuncheon 24341, South Korea.
[Ti] Título:Identification of capacitation inducers customized to sperm retrieved from inbred mouse epididymis.
[So] Source:Biochem Biophys Res Commun;488(2):273-277, 2017 Jun 24.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Acquisition of sperm capacitation post-ejaculation into the female reproductive tract is an essential step in the fertilization process. Accordingly, during in vitro fertilization, successful fertilization requires the induction of capacitation in epididymis-retrieved sperm. To date, many candidate substances have been considered as capacitation inducers; however, there are no reports on the efficiency of inducing sperm capacitation among the diverse inducers. Therefore, we attempted to determine the inducer with the best capacitation in inbred mouse sperm by comparing the capacitation performance of a variety of inducers and the percentage of in vitro fertilization-generated zygotes. Calcium chloride, progesterone, bovine serum albumin (BSA), heparin, and lysophosphatidylcholine (Lyso-PC) were used as candidate capacitation inducers. Optimized concentrations of each inducer (2.7 mM calcium, 15 µM progesterone, 0.3% (w/v) BSA, 50 mM heparin, and 100 µM Lyso-PC) were determined based on the ratio of sperm showing an acrosome reaction using Coomassie G-250 blue staining. Calcium at 2.7 mM showed the strongest capacitation induction compared to the other inducers. In vitro fertilization was performed using sperm incubated in each inducer and the ratio of fertilized oocytes was determined. Calcium at 2.7 mM and 0.3% (w/v) BSA showed the highest fertilization rates compared to 15 µM progesterone, 50 mM heparin, and 100 µM Lyso-PC. From these results, we found that 2.7 mM calcium and 0.3% (w/v) BSA were the most effective sperm capacitation inducers of mouse sperm for in vitro fertilization.
[Mh] Termos MeSH primário: Epididimo/efeitos dos fármacos
Capacitação Espermática/efeitos dos fármacos
Espermatozoides/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Cloreto de Cálcio/farmacologia
Relação Dose-Resposta a Droga
Heparina/farmacologia
Lisofosfatidilcolinas/farmacologia
Masculino
Camundongos
Camundongos Endogâmicos ICR
Progesterona/farmacologia
Soroalbumina Bovina/farmacologia
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lysophosphatidylcholines); 27432CM55Q (Serum Albumin, Bovine); 4G7DS2Q64Y (Progesterone); 9005-49-6 (Heparin); M4I0D6VV5M (Calcium Chloride)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE


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[PMID]:28250239
[Au] Autor:Singh DK; Deshmukh RK; Narayanan PK; Shivaji S; Siva AB
[Ad] Endereço:CSIR-Centre for Cellular and Molecular BiologyHyderabad 500007, India abs@ccmb.res.in
[Ti] Título:SRC family kinases in hamster spermatozoa: evidence for the presence of LCK.
[So] Source:Reproduction;153(5):655-669, 2017 05.
[Is] ISSN:1741-7899
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Sperm capacitation is a prerequisite for successful fertilization. Increase in tyrosine phosphorylation is considered the hallmark of capacitation and attempts to understand its regulation are ongoing. In this regard, we attempted to study the role of SRC family kinases (SFKs) in the hamster sperm functions. Interestingly, we found the presence of the lymphocyte-specific protein tyrosine kinase, LCK, in mammalian spermatozoa and further characterized it in terms of its localization and function. LCK was found in spermatozoa of several species, and its transcript was identified in the hamster testis. Autophosphorylation of LCK at the Y394 residue increased as capacitation progressed, indicating an upregulation of LCK activity during capacitation. Inhibition of LCK (and perhaps the other SFKs) with the use of a specific inhibitor showed a significant decrease in protein tyrosine phosphorylation of several proteins, implying LCK/SFKs as key tyrosine kinase(s) regulating tyrosine phosphorylation during hamster sperm capacitation. Dihydrolipoamide dehydrogenase was identified as a substrate for LCK/SFK. LCK/SFKs inhibition significantly reduced the percentage fertilization ( ) but had no effect on sperm motility, hyperactivation and acrosome reaction. In summary, this is the first report on the presence of LCK, an SFK of hematopoietic lineage in spermatozoa besides being the first study on the role of SFKs in the spermatozoa of Syrian hamsters.
[Mh] Termos MeSH primário: Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo
Capacitação Espermática/fisiologia
Espermatozoides/fisiologia
Testículo/fisiologia
Quinases da Família src/metabolismo
[Mh] Termos MeSH secundário: Reação Acrossômica
Animais
Células Cultivadas
Cricetinae
AMP Cíclico/metabolismo
Feminino
Fertilização In Vitro
Seres Humanos
Masculino
Mesocricetus
Oócitos/citologia
Oócitos/fisiologia
Fosforilação
Motilidade Espermática
Espermatozoides/citologia
Testículo/citologia
Tirosina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
42HK56048U (Tyrosine); E0399OZS9N (Cyclic AMP); EC 2.7.10.2 (Lymphocyte Specific Protein Tyrosine Kinase p56(lck)); EC 2.7.10.2 (src-Family Kinases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170303
[St] Status:MEDLINE
[do] DOI:10.1530/REP-16-0591


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[PMID]:28238530
[Au] Autor:Fernández S; Córdoba M
[Ad] Endereço:Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigación y Tecnología en Reproducción Animal (INITRA), Unidad Ejecutora de Investigaciones en Producción Animal UBA-CONICET (INPA), Cátedra de Química Biológica, Av. Chorroarín 280(1427), Ciudad Autónoma de Buenos Aires, Argentina.
[Ti] Título:A membrane-associated adenylate cyclase modulates lactate dehydrogenase and creatine kinase activities required for bull sperm capacitation induced by hyaluronic acid.
[So] Source:Anim Reprod Sci;179:80-87, 2017 Apr.
[Is] ISSN:1873-2232
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Hyaluronic acid, as well as heparin, is a glycosaminoglycan present in the female genital tract of cattle. The aim of this study was to evaluate oxidative metabolism and intracellular signals mediated by a membrane-associated adenylate cyclase (mAC), in sperm capacitation with hyaluronic acid and heparin, in cryopreserved bull sperm. The mAC inhibitor, 2',5'-dideoxyadenosine, was used in the present study. Lactate dehydrogenase (LDH) and creatine kinase (CK) activities and lactate concentration were determined spectrophotometrically in the incubation medium. Capacitation and acrosome reaction were evaluated by chlortetracycline technique, while plasma membrane and acrosome integrity were determined by trypan blue stain/differential interference contrast microscopy. Heparin capacitated samples had a significant decrease in LDH and CK activities, while in hyaluronic acid capacitated samples LDH and CK activities both increased compared to control samples, in heparin and hyaluronic acid capacitation conditions, respectively. A significant increase in lactate concentration in the incubation medium occurred in hyaluronic acid-treated sperm samples compared to heparin treatment, indicating this energetic metabolite is produced during capacitation. The LDH and CK enzyme activities and lactate concentrations in the incubation medium were decreased with 2',5'-dideoxyadenosine treatment in hyaluronic acid samples. The mAC inhibitor significantly inhibited heparin-induced capacitation of sperm cells, but did not completely inhibit hyaluronic acid capacitation. Therefore, hyaluronic acid and heparin are physiological glycosaminoglycans capable of inducing in vitro capacitation in cryopreserved bull sperm, stimulating different enzymatic pathways and intracellular signals modulated by a mAC. Hyaluronic acid induces sperm capacitation involving LDH and CK activities, thereby reducing oxidative metabolism, and this process is mediated by mAC.
[Mh] Termos MeSH primário: Adenilil Ciclases/metabolismo
Bovinos/fisiologia
Creatina Quinase/metabolismo
Ácido Hialurônico/farmacologia
L-Lactato Desidrogenase/metabolismo
Capacitação Espermática/efeitos dos fármacos
[Mh] Termos MeSH secundário: Adenilil Ciclases/genética
Animais
Creatina Quinase/genética
Regulação Enzimológica da Expressão Gênica
L-Lactato Desidrogenase/genética
Masculino
Capacitação Espermática/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9004-61-9 (Hyaluronic Acid); EC 1.1.1.27 (L-Lactate Dehydrogenase); EC 2.7.3.2 (Creatine Kinase); EC 4.6.1.1 (Adenylyl Cyclases)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170321
[Lr] Data última revisão:
170321
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170228
[St] Status:MEDLINE


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[PMID]:28238445
[Au] Autor:Guasti PN; Monteiro GA; Maziero RR; Carmo MT; Dell'Aqua JA; Crespilho AM; Rifai EA; Papa FO
[Ad] Endereço:Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, São Paulo State University, Botucatu, Brazil. Electronic address: priguasti@gmail.com.
[Ti] Título:Pentoxifylline effects on capacitation and fertility of stallion epididymal sperm.
[So] Source:Anim Reprod Sci;179:27-34, 2017 Apr.
[Is] ISSN:1873-2232
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The aims of this study were to determinate whether pentoxifylline (PTX) increases the motion parameters of fresh and frozen-thawed equine epididymal spermatozoa, to evaluate the tyrosine phosphorylation of frozen-thawed epididymal sperm in the presence of PTX and to determine whether the PTX-treatment of stallion epididymal sperm prior to freezing improves the fertility response of mares to a reduced number of spermatozoa per insemination dose. Fifty epididymis were flushed with a skim milk based extender with or without PTX. The pre-treatment with PTX enhanced the sperm motility after being harvested (P<0.05); however the freeze-thaw process did not alter the sperm kinematics between control and treated samples (P>0.05). Plasma membrane integrity did not differ between control and PTX group after recovery and after thawing (P>0.05), as observed in tyrosine phosphorylation, which the PTX treatment did not alter the percentage of tail-associated immunofluorescence of cryopreserved epididymal sperm (P>0.05). For the fertility trial, different insemination groups were tested: 800×10 epididymal sperm (C800); 100×10 epididymal sperm (C100); 100×10 epididymal sperm recovered in an extender containing PTX (PTX100). The conception rates for C800; C100 and PTX100 were 68.7% (11/16); 31.5% (5/16) and 50% (8/16), respectively. The conception rate did not differ among groups (P>0.05), however, a low number of animals was used in this study. A trend toward significance (P=0.07) was observed between C800 and C100 groups. In conclusion, PTX has no deleterious effect on sperm motility, viability and capacitation of cryopreserved stallion epididymal sperm. The conventional artificial insemination with 100×10 sperm recovered with PTX ensures acceptable conception rates and maximize the limited number of doses of cryopreserved stallion epididymal sperm.
[Mh] Termos MeSH primário: Epididimo/citologia
Cavalos/fisiologia
Pentoxifilina/farmacologia
Capacitação Espermática/efeitos dos fármacos
Espermatozoides/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Criopreservação/veterinária
Feminino
Fertilidade/efeitos dos fármacos
Masculino
Inibidores de Fosfodiesterase/farmacologia
Fosforilação
Gravidez
Preservação do Sêmen/veterinária
Motilidade Espermática/efeitos dos fármacos
Tirosina/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Phosphodiesterase Inhibitors); 42HK56048U (Tyrosine); SD6QCT3TSU (Pentoxifylline)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170321
[Lr] Data última revisão:
170321
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170228
[St] Status:MEDLINE


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[PMID]:28175305
[Au] Autor:Wong CW; Lam KKW; Lee CL; Yeung WSB; Zhao WE; Ho PC; Ou JP; Chiu PCN
[Ad] Endereço:Department of Obstetrics and Gynaecology, The University of Hong Kong, Queen Mary Hospital, Pokfulam Road, Hong Kong, Hong Kong SAR, China.
[Ti] Título:The roles of protein disulphide isomerase family A, member 3 (ERp57) and surface thiol/disulphide exchange in human spermatozoa-zona pellucida binding.
[So] Source:Hum Reprod;32(4):733-742, 2017 04 01.
[Is] ISSN:1460-2350
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Study question: Are multimeric sperm plasma membrane protein complexes, ERp57 and sperm surface thiol content involved in human spermatozoa-zona pellucida (ZP) interaction? Summary answer: ERp57 is a component of a multimeric spermatozoa-ZP receptor complex involved in regulation of human spermatozoa-ZP binding via up-regulation of sperm surface thiol content. What is known already: A spermatozoon acquires its fertilization capacity within the female reproductive tract by capacitation. Spermatozoa-ZP receptor is suggested to be a composite structure that is assembled into a functional complex during capacitation. Sperm surface thiol content is elevated during capacitation. ERp57 is a protein disulphide isomerase that modulates the thiol-disulphide status of proteins. Study design, size, duration: The binding ability and components of protein complexes in extracted membrane protein fractions of spermatozoa were studied. The roles of capacitation, thiol-disulphide reagent treatments and ERp57 on sperm functions and sperm surface thiol content were assessed. Participants/materials, setting, methods: Spermatozoa were obtained from semen samples from normozoospermic men. Human oocytes were obtained from an assisted reproduction programme. Blue native polyacrylamide gel electrophoresis, western ligand blotting and mass spectrometry were used to identify the components of solubilized ZP/ZP3-binding complexes. The localization and expression of sperm surface thiol and ERp57 were studied by immunostaining and sperm surface protein biotinylation followed by western blotting. Sperm functions were assessed by standard assays. Main results and the role of chance: Several ZP-binding complexes were isolated from the cell membrane of capacitated spermatozoa. ERp57 was a component of one of these complexes. Capacitation significantly increased the sperm surface thiol content, acrosomal thiol distribution and ERp57 expression on sperm surface. Sperm surface thiol and ERp57 immunoreactivity were localized to the acrosomal region of spermatozoa, a region responsible for ZP-binding. Up-regulation of the surface thiol content or ERp57 surface expression in vitro stimulated ZP-binding capacity of human spermatozoa. Blocking of ERp57 function by specific antibody or inhibitors against ERp57 reduced the surface thiol content and ZP-binding capacity of human spermatozoa. Large scale data: N/A. Limitations, reasons for caution: The mechanisms by which up-regulation of surface thiol content stimulates spermatozoa-ZP binding have not been depicted. Wider implications of the findings: Thiol-disulphide exchange is a crucial event in capacitation. ERp57 modulates the event and the subsequent fertilization process. Modulation of the surface thiol content of the spermatozoa of subfertile men may help to increase fertilization rate in assisted reproduction. Study funding/competing interest(s): This work was supported by The Hong Kong Research Grant Council Grant HKU764611 and HKU764512M to P.C.N.C. The authors have no competing interests.
[Mh] Termos MeSH primário: Isomerases de Dissulfetos de Proteínas/fisiologia
Interações Espermatozoide-Óvulo
Compostos de Sulfidrila/metabolismo
[Mh] Termos MeSH secundário: Acrossomo/metabolismo
Feminino
Seres Humanos
Masculino
Isomerases de Dissulfetos de Proteínas/genética
Capacitação Espermática
Espermatozoides/metabolismo
Compostos de Sulfidrila/análise
Regulação para Cima
Zona Pelúcida/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sulfhydryl Compounds); EC 5.3.4.1 (Protein Disulfide-Isomerases); EC 5.3.4.1. (PDIA3 protein, human)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170209
[St] Status:MEDLINE
[do] DOI:10.1093/humrep/dex007


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[PMID]:28166971
[Au] Autor:Chauhan DS; Swain DK; Shah N; Yadav HP; Nakade UP; Singh VK; Nigam R; Yadav S; Garg SK
[Ad] Endereço:College of Biotechnology, UP Pandit Deendayal Upadhayaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go Anusandhan Sansthan, Mathura, 281001, Uttar Pradesh, India.
[Ti] Título:Functional and molecular characterization of voltage gated sodium channel Na 1.8 in bull spermatozoa.
[So] Source:Theriogenology;90:210-218, 2017 Mar 01.
[Is] ISSN:1879-3231
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The aim of our study was to characterize the voltage gated sodium channel Na 1.8 in bull spermatozoa. Forty ejaculates were collected from four Hariana bulls and semen samples were pooled in view of the nonsignificant variations between different ejaculates. Functional characterization was undertaken using A-803467, a selective blocker of Na 1.8, and veratridine as an opener of the voltage gated sodium channels while molecular characterization was done using western blotting and indirect immunofluorescence assays. In vitro capacitation was induced using heparin, and to study the functional involvement of Na 1.8 in regulation of capacitation induced hyper sperm motility, A-803467 was used. Selective blocking of Na 1.8 by A-803467 at 6 and 8 µM concentration significantly (P < 0.05) decreased the forward progressive sperm motility in a time-dependent manner, while, blocking at higher concentrations (10 and 15 µM) resulted in fast forward motility in spermatozoa after 2 h of incubation and it was observed up to 3 h. Treatment of sperm cells with veratridine (6, 8, 10, 15, 20 µM) resulted in concentration- and time-dependent increase in forward progressive sperm motility and it persisted up to 4 h. However, hyperactive motility was induced by veratridine at higher concentrations (10 and 15 µM) after 2 h of incubation. In vitro capacitated spermatozoa treated with A-803467 revealed significant (P < 0.05) reduction in forward progressive motility after 2 h of incubation. Both A-803467 and veratridine altered the percentage of spermatozoa showing high mitochondrial transmembrane potential in concentration- and time-dependent manner. High concentrations (10 and 15 µM) of A-803467 and veratridine resulted in bent neck condition in spermatozoa along with significant (P < 0.05) reduction in membrane integrity (HOST negative). Immunoblot revealed the presence of a single protein band of 260 kDa molecular weight along with positive immunoreactivity (IR) in head, neck, middle piece and tail of the spermatozoa. Strongest IR was observed in the neck and middle piece whereas weak IR was observed in tail and acrosomal region of the spermatozoa. Results of our present study evidently revealed the presence of voltage gated sodium channel Na 1.8 in bull spermatozoa and its functional involvement in regulation of spermatozoa dynamics in terms of motility, membrane integrity, acrosome integrity, capacitation and mitochondrial transmembrane potential. Further studies are warranted to unravel their mechanistic pathways and/or their interaction with other ion channels in regulating sperm dynamics.
[Mh] Termos MeSH primário: Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo
Espermatozoides/metabolismo
[Mh] Termos MeSH secundário: Compostos de Anilina/farmacologia
Animais
Western Blotting
Bovinos
Furanos/farmacologia
Masculino
Potenciais da Membrana
Mitocôndrias/fisiologia
Capacitação Espermática/efeitos dos fármacos
Motilidade Espermática/efeitos dos fármacos
Espermatozoides/efeitos dos fármacos
Veratridina/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (A 803467); 0 (Aniline Compounds); 0 (Furans); 0 (NAV1.8 Voltage-Gated Sodium Channel); 71-62-5 (Veratridine)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170208
[St] Status:MEDLINE


  10 / 3097 MEDLINE  
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[PMID]:28115407
[Au] Autor:De Jonge C
[Ad] Endereço:Andrology Program, University of Minnesota Medical Center, 606 24th Avenue South, Suite 525, Minneapolis, MN 55454, USA.
[Ti] Título:Biological basis for human capacitation-revisited.
[So] Source:Hum Reprod Update;23(3):289-299, 2017 May 01.
[Is] ISSN:1460-2369
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: A little more than a decade ago a review entitled 'Biological basis for human capacitation' was published. A primary conclusion of the review was that with all the technological advances that have been made since the first experiments demonstrated the in vivo requirement of capacitation for fertilization, very little progress had since been made, most significantly for human. OBJECTIVE AND RATIONALE: The present review was carried out to provide an update on the biological basis for human capacitation. It briefly revisits the original schema, presents a review of the literature that urged research interest in human sperm capacitation and puts under the spotlight the original definition of capacitation balanced against the limitations of experiments in vitro to characterize a complex process that necessarily mandates a female component, and very recent findings in the mouse. It also includes proposed considerations for new thinking regarding capacitation, and progress toward understanding the biology of human capacitation. SEARCH METHODS: The PubMed, Google Scholar and Scopus literature databases were reviewed extensively using inclusive, broad and multispecies search terms without publication date limitation. OUTCOMES: Comprehensive screening of the literature database showed that no papers regarding human sperm capacitation in vivo have been published in the past 20 years. Recent experiments in the mouse have provided compelling and unanticipated data regarding capacitation and in vivo fertilization. Questions were posed and addressed regarding: stimuli for initiation of capacitation, capacitation relative to the cumulus-oocyte complex, comparison between in vivo and in vitro capacitation, and potential species-specific differences in location and timing of capacitation. WIDER IMPLICATIONS: There has been no progress on the in vivo biology of human sperm capacitation since before the turn of the century. Human IVF and its technologies may likely have inhibited, and continue to hold back, any future in vivo experiments that would address one or more questions regarding acquisition of fertilizing capacity in human. The limiting factor for progress in the area is access to funding and human subjects.
[Mh] Termos MeSH primário: Capacitação Espermática/fisiologia
Espermatozoides/fisiologia
[Mh] Termos MeSH secundário: Animais
Pesquisa Biomédica
Feminino
Seres Humanos
Masculino
Camundongos
Editoração/estatística & dados numéricos
Coelhos
Transporte Espermático/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170125
[St] Status:MEDLINE
[do] DOI:10.1093/humupd/dmw048



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