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1.
Mucosal Immunol ; 7(5): 1165-74, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24496317

RESUMO

Herpes Simplex virus Type-2 (HSV-2) increases the risk of HIV-1 acquisition, yet the mechanism for this viral pathogen to regulate the susceptibility of the cervicovaginal mucosa to HIV-1 is virtually unknown. Using ex vivo human ectocervical tissue models, we report greater levels of HIV-1 reverse transcription, DNA integration, RNA expression, and virions release in HIV-1/HSV-2 co-infected tissues compared with HIV-1 only infected tissues (P<0.05). Enhanced HIV-1 replication was associated with increased CD4, CCR5, and CD38 transcription (P<0.05) and increased number of CD4(+)/CCR5(+)/CD38(+) T cells in HIV-1/HSV-2 co-infected tissues compared with tissues infected with HIV-1 alone. Tenofovir (TFV) 1% gel, the leading microbicide candidate, demonstrated only partial protection against HIV-1, when applied vaginally before and after sexual intercourse. It is possible that mucosal inflammation, in particular that induced by HSV-2 infection, may have decreased TFV efficacy. HSV-2 upregulated the number of HIV-1-infected cells and elevated the concentration of TFV needed to decrease HIV-1 infection. Similarly, only high concentrations of TFV inhibited HSV-2 replication in HIV-1/HSV-2-infected tissues. Thus, HSV-2 co-infection and mucosal immune cell activation should be taken into consideration when designing preventative strategies for sexual transmission of HIV-1.


Assuntos
Colo do Útero/virologia , Infecções por HIV/transmissão , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Herpesvirus Humano 2/fisiologia , Tenofovir/farmacologia , Replicação Viral , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/metabolismo , Antivirais/farmacologia , Feminino , Regulação da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase
2.
Int J STD AIDS ; 23(9): 613-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23033511

RESUMO

Sexual transmission of HIV-1, in the absence of co-factors, is poorly efficient. Data support that herpes simplex virus type-2 (HSV-2) may increase a woman's susceptibility to HIV-1. Potential mechanisms by which HSV-2 serves as an HIV-1 enhancing co-factor include (1) initiation of a clinical or subclinical mucosal inflammatory response, (2) alteration of innate mucosal immunity and (3) weakening or breaching the protective genital epithelia. No clinical trial has examined prevention of primary HSV-2 infection to eliminate the major morbidities of this recurrent disease and as a strategy to reduce HIV-1 transmission. Topical administration of potent antivirals can achieve local concentrations that are orders of magnitude higher than those obtained with oral administration. This paper reviews major advances in oral and topical pre-exposure prophylaxis of HIV-1 and HSV-2 and, based on these data, hypothesizes that simultaneous prevention of sexual acquisition of HSV-2 and HIV-1 via topical antiretroviral agents will have a synergistic impact on both epidemics.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , HIV/fisiologia , Herpes Genital/prevenção & controle , Herpes Genital/virologia , Herpesvirus Humano 2/fisiologia , Aciclovir/administração & dosagem , Fármacos Anti-HIV/administração & dosagem , Antivirais/administração & dosagem , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Herpes Genital/tratamento farmacológico , Herpes Genital/transmissão , Interações Hospedeiro-Patógeno , Humanos
3.
Antimicrob Agents Chemother ; 53(4): 1490-500, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19139286

RESUMO

Topical microbicides are being developed as a preventative approach to reduce the sexual transmission of human immunodeficiency virus type 1 (HIV-1) and other infections. For them to be efficacious, it is believed that they should avoid inducing inflammation while allowing the vaginal epithelium to initiate protective Toll-like receptor (TLR)-mediated innate responses against pathogens. In this study, human cervical and vaginal epithelial cells were exposed to polyanionic HIV entry inhibitors and the following synthetic TLR ligands: (i) the bacterial lipoprotein Pam(3)CSK(4), binding cell surface TLR1/TLR2; (ii) macrophage activating lipopeptide 2 (MALP-2), binding cell surface TLR2/TLR6; and (iii) the viral double-stranded RNA analog poly(I:C), recognized by intracellular TLR3. Cell activation was assessed by nuclear factor kappaB (NF-kappaB) reporter gene transactivation and cytokine production. In spite of enhancing TLR-triggered NF-kappaB activation, the polyanionic microbicide compounds dextran sulfate and polystyrene sulfonate significantly inhibited TLR-mediated cytokine production. They decreased cytokine mRNA and protein levels of proinflammatory (interleukin-8 [IL-8] and IL-1beta) and antiviral (beta interferon) cytokines following epithelial cell stimulation with Pam(3)CSK(4), MALP-2, or poly(I:C). These activities were associated with the sulfate/sulfonate moieties of the polyanionic compounds, since the unsulfated dextran control did not show any effects. Our data demonstrate that these microbicide compounds are capable of selectively interfering with TLR-mediated epithelial responses at different points in their signaling pathways and underscore the importance of expanding the assessment of microbicide compatibility with vaginal innate immune function. Further studies are warranted to determine the impact of this interference on HIV-1 transmission risk.


Assuntos
Anti-Infecciosos/farmacologia , Colo do Útero/imunologia , Imunidade Inata/efeitos dos fármacos , Polímeros/farmacologia , Receptores Toll-Like/fisiologia , Vagina/imunologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Linhagem Celular , Citocinas/biossíntese , Citocinas/genética , Feminino , HIV-1/efeitos dos fármacos , Humanos , Lipopeptídeos/farmacologia , NF-kappa B/metabolismo , Poli I-C/farmacologia , Polieletrólitos , Transdução de Sinais
4.
Hum Reprod ; 22(3): 743-50, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17110399

RESUMO

BACKGROUND: The compaction of human sperm chromatin is the result of replacement of approximately 85% of histones with protamines. Germ-line testis/sperm-specific histone 2B (TSH2B) has been detected in only approximately 30% of mature spermatozoa. Its level in the semen of subfertile patients varies; its function is unknown. We evaluated TSH2B in the sperm samples of 23 donors and 49 subfertile patients and assessed its association with chromatin compaction status. METHODS: TSH2B level was measured using immunoblotting. Chromatin packaging quality was evaluated by staining with chromomycin A3 (CMA3) which marked spermatozoa with defective packaging. To assess both TSH2B and chromatin status in the same spermatozoon, CMA3 staining and TSH2B immunolocalization were performed sequentially. RESULTS: A significant correlation (r = 0.55, P = 0.0027) was found between TSH2B level and percentage of CMA3-positive sperm in patient and donor semen samples. When individual spermatozoa were assessed for these parameters, 92% of TSH2B-containing cells were also CMA3 positive. Variation in the total sperm TSH2B level was less in donors than in patients. CONCLUSIONS: CMA3 positive staining of TSH2B-containing individual spermatozoa and a significant correlation between the total TSH2B level and CMA3 percentage in semen samples suggest a structural role for TSH2B in sperm chromatin organization. Low variability of TSH2B level in donors implies a mechanism (however unknown) regulating this parameter.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Cromatina/metabolismo , Histonas/análise , Infertilidade Masculina/metabolismo , Espermatozoides/química , Testículo/química , Cromomicina A3 , Imunofluorescência , Humanos , Masculino , Protaminas/metabolismo , Sêmen/química , Doadores de Tecidos
5.
Mol Reprod Dev ; 73(12): 1591-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16897700

RESUMO

Varicocele is a prevalent pathology among infertile men. The mechanisms linking this condition to infertility, however, are poorly understood. Our previous work showed a relationship between sperm functional quality and the ability of spermatozoa to respond to capacitating conditions with increased membrane fluidity and protein tyrosine phosphorylation. Given the reported association between varicocele, oxidative stress, and sperm dysfunction, we hypothesized that spermatozoa from infertile patients with varicocele might have a combined defect at the level of membrane fluidity and protein tyrosine phosphorylation. Semen samples from infertile patients with and without grade II/III left varicocele were evaluated for motion parameters (computer-assisted semen analysis [CASA]), hyperactivation (CASA), incidence and intensity of protein tyrosine phosphorylation (phosphotyrosine immunofluorescence and western blotting), and membrane fluidity (Laurdan fluorometry), before and after a capacitating incubation (6 hr at 37 degrees C in Ham's F10/BSA, 5% CO(2)). Spermatozoa from varicocele samples presented a decreased response to the capacitating challenge, showing significantly lower motility, hyperactivation, incidence and intensity of tyrosine phosphorylation, and membrane fluidity. The findings reported in this article indicate that the sperm dysfunction associated to infertile varicocele coexists with decreased sperm plasma membrane fluidity and tyrosine phosphorylation. These deficiencies represent potential new pathophysiological mechanisms underlying varicocele-related infertility.


Assuntos
Infertilidade Masculina/etiologia , Fluidez de Membrana/fisiologia , Proteínas Tirosina Quinases/metabolismo , Espermatozoides/metabolismo , Varicocele/complicações , Adulto , Membrana Celular/fisiologia , Humanos , Masculino , Fosforilação , Motilidade dos Espermatozoides
6.
Biol Reprod ; 71(3): 761-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15128598

RESUMO

Inflammation of the female reproductive tract increases susceptibility to HIV-1 and other viral infections and, thus, it becomes a serious liability for vaginal products. Excessive release of proinflammatory cytokines may alter the mucosal balance between tissue destruction and repair and be linked to enhanced penetration and replication of viral pathogens upon chemical insult. The present study evaluates four surface-active microbicide candidates, nonoxynol-9 (N-9), benzalkonium chloride (BZK), sodium dodecyl sulfate, and sodium monolaurate for their activity against human sperm and HIV, and their capacity to induce an inflammatory response on human vaginal epithelial cells and by the rabbit vaginal mucosa. Spermicidal and virucidal evaluations ranked N-9 as the most potent compound but were unable to predict the impact of the compounds on vaginal cell viability. Interleukin (IL)-1 release in vitro reflected their cytotoxicity profiles more accurately. Furthermore, IL-1 concentrations in vaginal washings correlated with cumulative mucosal irritation scores after single and multiple applications (P < 0.01), showing BZK as the most damaging agent for the vaginal mucosa. BZK induced rapid cell death, IL-1 release, and IL-6 secretion. The other compounds required either more prolonged or repeated contact with the vaginal epithelium to induce a significant inflammatory reaction. Increased IL-8 levels after multiple applications in vivo identified compounds with the highest cumulative mucosal toxicity (P < 0.01). In conclusion, IL-1, IL-6, and IL-8 in the vaginal secretions are sensitive indicators of compound-induced mucosal toxicity. The described evaluation system is a valuable tool in identifying novel vaginal contraceptive microbicides, selecting out candidates that may enhance, rather than decrease, HIV transmission.


Assuntos
Interleucinas/imunologia , Nonoxinol/toxicidade , Espermicidas/toxicidade , Vagina/efeitos dos fármacos , Vagina/imunologia , Animais , Anti-Infecciosos Locais/toxicidade , Compostos de Benzalcônio/toxicidade , Biomarcadores , Muco do Colo Uterino/efeitos dos fármacos , Muco do Colo Uterino/imunologia , Células Epiteliais/citologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/efeitos dos fármacos , Interleucina-1/imunologia , Interleucina-1/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Interleucina-8/imunologia , Interleucina-8/metabolismo , Interleucinas/metabolismo , Valor Preditivo dos Testes , Coelhos , Dodecilsulfato de Sódio/toxicidade , Motilidade dos Espermatozoides/efeitos dos fármacos , Tensoativos/toxicidade , Vagina/patologia
7.
Hum Reprod ; 19(1): 139-46, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14688172

RESUMO

BACKGROUND: Human semen is composed of a heterogeneous population of sperm with varying degrees of structural and functional differentiation and normality, which result in subpopulations of different quality. METHODS: Using a discontinuous Percoll gradient, we separated three subsets of sperm [(45%; L45), (65%; L65) and (90%; L90) fractions] from normozoospermic human semen samples from healthy donors and proceeded to characterize their morphology, motility and hyperactivation, as well as their ability to undergo tyrosine phosphorylation under capacitating conditions. RESULTS: As expected, sperm isolated from the lowest density layer (L45) showed the poorest quality, displaying the smallest percentage of morphologically normal and motile sperm. During a capacitating incubation, this subset of cells also showed deficient capacity to undergo hyperactivation and protein tyrosine phosphorylation. Conversely, sperm isolated from the other layers (L65 and L90) showed a time-dependent progressive increment in tyrosine phosphorylation, establishing statistically significant differences with sperm from L45. The tyrosine phosphorylation deficiency of L45 sperm could be overcome when sperm from that fraction were stimulated with activators of the cAMP-dependent kinase (PKA) pathway (dbcAMP + pentoxifylline), pointing to the sperm's plasma membrane as the main site of such deficiency. CONCLUSIONS: Poor quality sperm isolated from a Percoll gradient display an intrinsic tyrosine phosphorylation deficiency, possibly caused by a plasma membrane defect, which is associated with their inability to undergo normal capacitation and, ultimately, acquire optimal fertilizing potential.


Assuntos
Espermatozoides/citologia , Espermatozoides/fisiologia , Tirosina/metabolismo , Bucladesina/farmacologia , Centrifugação com Gradiente de Concentração , Coloides , Humanos , Masculino , Movimento (Física) , Pentoxifilina/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Fosforilação/efeitos dos fármacos , Povidona , Valores de Referência , Dióxido de Silício , Capacitação Espermática , Motilidade dos Espermatozoides , Espermatozoides/metabolismo
8.
Mol Reprod Dev ; 66(4): 422-30, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14579418

RESUMO

Human ejaculated sperm comprised discrete subsets of spermatozoa, with different degrees of maturation. These subpopulations can be isolated through density gradient centrifugation. Sperm from the lowest density layer show the highest content of docosahexaenoic acid and sterols, and produce the highest levels of reactive oxygen species. The main objective of this study was to determine the superoxide dismutase (SOD) content and fatty acid composition of subsets of spermatozoa isolated from normozoospermic, asthenozoospermic, and polyzoospermic semen samples. Four sperm fractions (1-4) were obtained using ISolate gradient centrifugation. Morphology, motion parameters, SOD content, and fatty acid composition were assessed in the original samples and their fractions. Overall, sperm from normozoospermic samples had higher SOD content than those of asthenozoospermic or polyzoospermic samples. Once fractionated in subsets, the sperm SOD content decreased significantly (P < 0.0001) from fraction 1 (top) to 4 (bottom) in all three groups of samples. Fatty acid content as well as the oxidation coefficient followed the same pattern, decreasing from fraction 1 to 4 (F1-F4). Normo- and polyzoospermic samples showed similar amounts of fatty acids, while asthenozoospermic samples mostly revealed increased levels. Normozoospermic samples displayed the lowest unsaturated fatty acid (UFA)/SOD ratio. Spermatozoa from astheno- and polyzoospermic samples, two common seminal pathologies, showed higher UFA and lower SOD content than normal sperm, therefore exhibiting a higher susceptibility to peroxidative damage. F4 from all groups, containing the most mature spermatozoa, displayed the lowest polyunsaturated fatty acid and SOD content of all subsets, suggesting that excessive SOD activity as well as abundant peroxidative targets may both be deleterious to sperm function.


Assuntos
Ácidos Graxos/análise , Espermatozoides/química , Espermatozoides/citologia , Superóxido Dismutase/metabolismo , Adulto , Ácidos Graxos/química , Humanos , Infertilidade Masculina/patologia , Masculino , Motilidade dos Espermatozoides , Espermatozoides/enzimologia , Espermatozoides/patologia
9.
Reproduction ; 126(2): 183-95, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12887275

RESUMO

Tyrosine phosphorylation and its upregulation by cAMP have been associated with capacitation and motility changes of spermatozoa. In the present study, washed spermatozoa were incubated for 6 h in protein-supplemented complete medium with or without kinase inhibitors to verify whether upstream activation of protein kinase A is indispensable for tyrosine phosphorylation and motility changes to occur in capacitating human spermatozoa. H89, a specific protein kinase A inhibitor, significantly inhibited the activity of sperm protein kinase A. However, this inhibition did not alter capacitation-related tyrosine kinase activation. Tyrosine phosphorylated proteins, motion parameters and the incidence of phosphotyrosine-immunoreactive spermatozoa were decreased only slightly. Conversely, genistein, a tyrosine kinase inhibitor which inhibited sperm tyrosine kinase but not protein kinase A, significantly reduced all the parameters studied. Spermatozoa incubated with cAMP and pentoxifylline showed a rapid enhancement of tyrosine phosphorylation and some of the sperm motion parameters, particularly hyperactivation. Inclusion of H89 reduced cAMP stimulation of tyrosine kinase, and tyrosine phosphorylation and motion parameters were reduced almost to basal values. Treatment with genistein reduced tyrosine kinase activity, especially in the soluble fraction of sperm extracts. A decrease in tyrosine phosphorylation of soluble proteins, 105, 81, 55 and 48 kDa, correlated with a significant reduction in sperm motion parameters. Hyperactivation was reduced by tenfold. Tyrosine phosphorylated proteins in the insoluble fraction and the incidence of tyrosine phosphorylated-positive spermatozoa were not reduced markedly. Upstream protein kinase A activation may be a facilitatory rather than an indispensable step in the capacitation-induced tyrosine phosphorylation mediating motility changes in human spermatozoa. Triton-x100 soluble tyrosine phosphorylated proteins, more than their insoluble counterparts, appear to be involved in the modulation of human sperm motion characteristics.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Tirosina Quinases/metabolismo , Motilidade dos Espermatozoides/fisiologia , Sulfonamidas , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Técnica Indireta de Fluorescência para Anticorpo , Genisteína/farmacologia , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Isoquinolinas/farmacologia , Masculino , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptor Cross-Talk/fisiologia , Capacitação Espermática/fisiologia , Estatísticas não Paramétricas
10.
Arch Androl ; 49(3): 229-46, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12746102

RESUMO

Tyrosine phosphorylation has recently been associated with capacitation and suggested as a regulator of sperm movement, especially characterizing hyperactivation. The objective of this study was to verify if tyrosine phosphorylation of human sperm proteins was essentially required for the maintenance of motility as well as the development of hyperactivation. Washed sperm were incubated for 6 h in Ham's F10 + 0.35% HSA at 37 degrees C in 5% CO(2), with and without the tyrosine kinase inhibitors genistein, tyrphostin, erbstatin, or herbimycin A and the wide-spectrum kinase inhibitor staurosporin. The concentrations of the inhibitors used in the experiments did not induce sperm toxicity, as measured by membrane integrity and mitochondrial function assays. Samples incubated without the inhibitors (control), increased their tyrosine kinase activity (ELISA), the number and intensity of tyrosine-phosphorylated (PY) protein bands (Western blot), the incidence of PY-immunoreactive sperm (immunofluorescence), and some of the sperm motion characteristics (CASA), such as velocity (VEL), amplitude of lateral head displacement (ALH), and hyperactivation. Among the selective protein tyrosine kinase inhibitors, genistein was the most active and consistent, inhibiting sperm tyrosine kinase activity, PY proteins, incidence of PY sperm, and sperm motility and motion parameters, such as VEL, ALH, and hyperactivation. The rest of the kinase inhibitors decreased motion characteristics to a varied extent and had different effects on phosphorylation parameters. In general, they decreased PY phosphorylation of 2 proteins (83 and 54 kDa) present in whole sperm extracts, and two sets of proteins of low (39-49 kDa) and medium (55-87 kDa) molecular weight present in the Triton X-100-solubilized sperm protein fraction. This inhibition was evident regardless of the total tyrosine kinase activity of the samples or the incidence of PY-immunoreactive sperm. The described findings further support the association between motility and protein tyrosine phosphorylation in human sperm and point to certain proteins as the main linkers.


Assuntos
Proteínas Tirosina Quinases/antagonistas & inibidores , Motilidade dos Espermatozoides , Tirosina/metabolismo , Sequência de Aminoácidos , Northern Blotting , Western Blotting , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Fosforilação
11.
Biocell ; 27(1): 29-36, Apr. 2003.
Artigo em Inglês | LILACS | ID: lil-384253

RESUMO

Our objective was to study the incidence of sperm-tail phosphotyrosine immunoreactivity in normozoospermic and asthenozoospermic human sperm samples, its association with sperm motion parameters, particularly hyperactivated motility, and its potential involvement in the pathogenesis of asthenozoospermia. The work was conducted as a prospective experimental study in the Sperm Biology and Andrology laboratories of the Jones Institute, a medical school-based fertility center. The study subjects were healthy fertile male donors (normozoospermic samples) and infertile patients (asthenozoospermic samples) attending the center. Recently ejaculated semen samples were washed twice to eliminate seminal plasma and a swim-up was performed to select the motile population which, in turn, was incubated up to 18 h at 37 degrees C in 3.5% human serum albumin-supplemented Ham's F10 to allow for capacitation. For evaluation, sperm aliquots were taken pre-swim-up (T0), immediately post swim-up (T1), at 6 h (T6), and 18 h (T18) of incubation. The main outcome measures were computer-analyzed sperm motion parameters and hyperactivated motility, and immunodetection of phosphotyrosine (PY)-containing proteins. During the capacitating incubation, normozoospermic samples displayed maximum motility, velocity, and hyperactivation at T6, significantly decreasing their values at T18. PY-proteins were located both at the tail and head of spermatozoa. Their expression increased progressively during the incubation, being present in about 70% of the sperm tails at T18. Asthenozoospermic samples showed an inability to respond to capacitation with an increase in motion parameters and PY-phosphorylation. At T6, both hyperactivation and PY-phosphorylation were significantly lower than in normal samples. Our results suggest that PY-phosphorylation of tail proteins is highly conspicuous in human spermatozoa, and increases its incidence in a time-dependent manner, as more sperm become capacitated. Asthenozoospermic samples displaying low percentages of motile sperm and altered motion characteristics showed a decreased incidence of PY-phosphorelated sperm. Tail protein PY-phosphorylation may be related to sperm movement, especially to hyperactivated motility and its deficiency may be associated to asthenozoospermia.


Assuntos
Humanos , Masculino , Cauda do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Infertilidade Masculina , Motilidade dos Espermatozoides/fisiologia , Tirosina/metabolismo , Fosforilação , Capacitação Espermática , Fatores de Tempo
12.
Biocell ; 27(1): 29-36, Apr. 2003.
Artigo em Inglês | BINACIS | ID: bin-3978

RESUMO

Our objective was to study the incidence of sperm-tail phosphotyrosine immunoreactivity in normozoospermic and asthenozoospermic human sperm samples, its association with sperm motion parameters, particularly hyperactivated motility, and its potential involvement in the pathogenesis of asthenozoospermia. The work was conducted as a prospective experimental study in the Sperm Biology and Andrology laboratories of the Jones Institute, a medical school-based fertility center. The study subjects were healthy fertile male donors (normozoospermic samples) and infertile patients (asthenozoospermic samples) attending the center. Recently ejaculated semen samples were washed twice to eliminate seminal plasma and a swim-up was performed to select the motile population which, in turn, was incubated up to 18 h at 37 degrees C in 3.5% human serum albumin-supplemented Hams F10 to allow for capacitation. For evaluation, sperm aliquots were taken pre-swim-up (T0), immediately post swim-up (T1), at 6 h (T6), and 18 h (T18) of incubation. The main outcome measures were computer-analyzed sperm motion parameters and hyperactivated motility, and immunodetection of phosphotyrosine (PY)-containing proteins. During the capacitating incubation, normozoospermic samples displayed maximum motility, velocity, and hyperactivation at T6, significantly decreasing their values at T18. PY-proteins were located both at the tail and head of spermatozoa. Their expression increased progressively during the incubation, being present in about 70% of the sperm tails at T18. Asthenozoospermic samples showed an inability to respond to capacitation with an increase in motion parameters and PY-phosphorylation. At T6, both hyperactivation and PY-phosphorylation were significantly lower than in normal samples. Our results suggest that PY-phosphorylation of tail proteins is highly conspicuous in human spermatozoa, and increases its incidence in a time-dependent manner, as more sperm become capacitated. Asthenozoospermic samples displaying low percentages of motile sperm and altered motion characteristics showed a decreased incidence of PY-phosphorelated sperm. Tail protein PY-phosphorylation may be related to sperm movement, especially to hyperactivated motility and its deficiency may be associated to asthenozoospermia. (AU)


Assuntos
Estudo Comparativo , Humanos , Masculino , RESEARCH SUPPORT, NON-U.S. GOVT , Infertilidade Masculina , Motilidade dos Espermatozoides/fisiologia , Cauda do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Tirosina/metabolismo , Fosforilação , Capacitação Espermática , Fatores de Tempo
13.
Andrologia ; 34(2): 63-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11966571

RESUMO

We previously reported a modified sperm stress test (MOST), low scores (< 0.39) in which were associated with sperm-related abnormal in vitro fertilization. Preliminary observations suggested that the presence of male sperm antibodies (ASA) could give low MOST scores. It was therefore decided to undertake a study to verify this possible association and also to ascertain if such a relationship was causal in nature. Six hundred and fifty semen samples from patients consulting for infertility were assessed for basic seminal characteristics, motion parameters (CASA), ASA and MOST. Thirty-nine samples (6%) were ASA-positive. Samples with and without ASA showed similar characteristics, except for percentage of normal forms and MOST scores (0.35 +/- 0.03 vs. 0.67 +/- 0.01, P < 0.001, for ASA-positive and -negative, respectively). There was a strong statistical association between presence of ASA and low MOST scores (P < 0.0001). One-hundred per cent of ASA-positive samples displayed low MOST scores. To verify the nature of this relationship, we incubated ASA-free spermatozoa with ASA-positive and -negative (control) sera. Despite an increase in the percentage of ASA-bearing spermatozoa in those aliquots incubated with ASA-positive serum, their original (pre-incubation) MOST scores remained unchanged. Furthermore, the rate of lipid peroxidation, indirectly reflected in MOST scores, was not different in the aliquots incubated with ASA. In conclusion, there seems to be a strong association between presence of ASA and low MOST values in semen samples of infertile patients; however, the relationship does not appear to be causal.


Assuntos
Autoanticorpos/análise , Infertilidade Masculina/imunologia , Peroxidação de Lipídeos , Sêmen/imunologia , Espermatozoides/imunologia , Humanos , Infertilidade Masculina/metabolismo , Masculino , Sêmen/metabolismo , Espermatozoides/metabolismo
14.
Contraception ; 64(2): 93-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11704085

RESUMO

Four sexually mature male baboons (Papio sp.) were immunized with a chimeric peptide containing a B-cell epitope of the testis-specific lactate dehydrogenase (LDH-C(4)) and a promiscuous T-cell epitope of tetanus toxin. LDH-C(4) is the testis-specific isozyme of lactate dehydrogenase, and antibodies to this protein reduce fertility significantly in female nonhuman primates. Animals were immunized on Day 0 and received booster injections at Days 29, 61, and 344 after priming. Serum specific antibodies were determined at regular intervals during the initial 6 months and after the last booster. Testis biopsies were taken at Days 61, 127, and 183 after the primary immunization. Sperm-zona binding was assessed prior to and three times after the last booster. The present study demonstrated that this epitope of LDH-C(4) did not cause autoimmune disease and that sperm from these immunized males had a diminished zona binding capacity. These results suggest that a safe male immunocontraceptive based on development of anti-sperm antibodies may be feasible.


Assuntos
Anticorpos/sangue , Anticoncepção Imunológica , Imunização , Isoenzimas/imunologia , L-Lactato Desidrogenase/imunologia , Testículo/imunologia , Animais , Autoimunidade , Biópsia , Anticoncepção Imunológica/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Cinética , Masculino , Papio , Interações Espermatozoide-Óvulo , Espermatozoides/fisiologia , Testículo/anatomia & histologia
15.
Andrologia ; 33(2): 79-86, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11350371

RESUMO

Prolonged incubation of human spermatozoa can have deleterious effects on sperm function. The aim of this paper was to describe the effects of a prolonged in vitro incubation, under similar conditions to those employed in human assisted reproduction, on various sperm functional parameters, and to investigate the effect of an antioxidant (catalase) on this system. Freshly collected ejaculates from 20 healthy donors were studied. Samples were divided into two aliquots: the first was incubated with Ham's F10 containing 3.5% HAS, and the second was incubated in the same medium plus catalase (100 units ml-1). All experiments were carried out with spermatozoa isolated using the swim-up technique. Spermatozoa recovered from the supernatant after 1 h (T1) of incubation in 5% CO2 in air at 37 degrees C, and after 5 h (T6), 23 h (T24) and 47 h (T48), were evaluated for concentration, motion parameters including hyperactivation (computer-assisted analysis), viability, ATP concentration, reactive oxygen species (ROS) generation, DNA integrity (acridine orange), and acrosome reaction (AR). The major alteration observed in sperm function during the prolonged in vitro incubation was a reduction in the number of motile spermatozoa, together with an impairment in the quality of sperm movement. ROS levels increased with the incubation time. No substantial modifications of sperm viability, chromatin condensation and AR inducibility were observed. The addition of catalase to the medium, while keeping ROS values within baseline levels, did not prevent the loss of motility or the corresponding increase in ATP.


Assuntos
Catalase/farmacologia , Espermatozoides/fisiologia , Reação Acrossômica , Trifosfato de Adenosina/metabolismo , DNA/análise , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Espécies Reativas de Oxigênio/metabolismo , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo
16.
J Androl ; 21(6): 862-75, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11105913

RESUMO

A commercial preparation of a sodium polystyrene sulfonate (designated as N-PSS; its molecular weight is 500000 daltons) was tested as an inhibitor of sperm function and as a preventive agent for conception and the transmission of sexually transmitted diseases. The polymer is an irreversible inhibitor of hyaluronidase and acrosin; its IC50 values are 5.7 microg/mL and 0.5 microg/mL, for hyaluronidase and acrosin, respectively. N-PSS is also a stimulus of human sperm acrosomal loss. It produces maximal acrosomal loss at 2.5 microg/mL. Contraception in rabbits is nearly complete when rabbit spermatozoa are pretreated with 0.5 mg/mL of N-PSS before artificial insemination; however, N-PSS does not immobilize spermatozoa at concentrations as high as 50 mg/mL. N-PSS has broad spectrum antiviral and antibacterial activities. Infection by human immunodeficiency virus and herpes simplex virus are inhibited by N-PSS; 3-log reductions are produced by 7 microg/mL and 3 microg/mL, respectively. N-PSS is active against Chlamydia trachomatis and Neisseria gonorrhoeae. At 1 mg/mL, N-PSS inhibits chlamydial infectivity by more than 90%. N-PSS produces a 3-log reduction in gonococcal growth at 15 microg/mL. In contrast, N-PSS (5 mg/mL) does not affect the growth of Lactobacillus (normal component of the vaginal flora). N-PSS can be classified as a noncytotoxic contraceptive antimicrobial agent. These properties justify bringing a polystyrene sulfonate into clinical trials for its evaluation as a preventive agent for conception and several sexually transmitted diseases.


Assuntos
Anti-Infecciosos/farmacologia , Hialuronoglucosaminidase/antagonistas & inibidores , Poliestirenos/farmacologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Antibacterianos , Antivirais/farmacologia , Chlamydia trachomatis/efeitos dos fármacos , Feminino , HIV/efeitos dos fármacos , Humanos , Inseminação Artificial , Masculino , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/efeitos dos fármacos , Coelhos , Infecções Sexualmente Transmissíveis/transmissão , Simplexvirus/efeitos dos fármacos , Espermatozoides/fisiologia
17.
Mol Cell Probes ; 14(2): 89-93, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10799269

RESUMO

The number of nucleotide triplet repeats in 16 S rRNA sequences can be used for detection and identification of bacteria. Labelled TTT, GGG and ATA triplets were hybridized to the ribonucleic acid of Bacillus subtilis and Bacillus fusiformis whole-cells and the number of such triplets was quantified by synchronous fluorescence spectrometry. Each species was distinctly identified by specific ratios of labelled TTT, GGG and ATA triplets as well as characteristic fluorescence spectra. Notwithstanding the absence of intrinsic specificity, fluorescein-conjugated nucleotide triplet probes appear to be a useful tool for fluorescent spectrometric identification of micro-organisms through the quantitation of trinucleotide repeats.


Assuntos
Bacillus/genética , Bacillus/isolamento & purificação , Hibridização in Situ Fluorescente , Repetições de Trinucleotídeos , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Fluoresceína/química , Corantes Fluorescentes/química , Nucleotídeos/química
18.
Am J Reprod Immunol ; 43(3): 144-51, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10735590

RESUMO

PROBLEM: Recent reports indicate high incidence of genital infections, most of which are sexually transmitted. Although specific drugs and antibiotics are available for some, a safe spermicidal formulation with wide spectrum antimicrobial action would be a desirable addition to the presently available spermicides. METHODS: Formulations at different dilutions were tested in culture systems on standard strains and clinical isolates including some isolates resistant to drugs. The effect on (HSV)-2 and Chlamydia trachomatis was determined in vivo in progestin sensitized mice. The effect on HIV-1 was investigated in two standardized systems. RESULTS: Polyherbal cream inhibited the growth in culture of clinical isolates of Candida albicans, Candida krusei and Candida tropicalis. Both the polyherbal cream and the Praneem polyherbal pessary inhibited urinary tract Escherichia coli (including multidrug resistant strains), and Neisseria gonorrhoeae (including 2 strains resistant to penicillin). Both formulations manifested virucidal activity against HIV-1 at >2 and 50% dilutions (in two different test systems) on contact for 1-2 min. Intravaginal inoculation of the cream and the pessary suspensions before inoculation of the pathogen prevented lesions and vaginal transmission of HSV-2 and C. trachomatis in progestin sensitized mice. CONCLUSIONS: Polyherbal formulations have wide spectrum antibacterial, antifungal and antiviral effect against the tested sexually transmitted pathogens.


Assuntos
Anti-Infecciosos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Quinina/farmacologia , Doenças Bacterianas Sexualmente Transmissíveis/prevenção & controle , Doenças Virais Sexualmente Transmissíveis/prevenção & controle , Cremes, Espumas e Géis Vaginais/farmacologia , Animais , Antibacterianos , Fármacos Anti-HIV/farmacologia , Antifúngicos/farmacologia , Antivirais/farmacologia , Candida albicans/efeitos dos fármacos , Chlamydia trachomatis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , HIV-1/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neisseria gonorrhoeae/efeitos dos fármacos , Doenças Bacterianas Sexualmente Transmissíveis/microbiologia , Doenças Virais Sexualmente Transmissíveis/virologia
19.
Fertil Steril ; 73(4): 788-98, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10731542

RESUMO

OBJECTIVE: To reassess endometrial morphological criteria of normality identifying the best morphological and molecular "implantation window" indicators in normal women. DESIGN: Prospective clinical study. SETTING: Assisted reproductive unit. PATIENT(S): Fourteen healthy volunteers. INTERVENTION(S): Blood sampling for LH, E(2), and progesterone (P4) determinations. Daily vaginal ultrasounds. Two endometrial biopsies per volunteer, 7 days apart, during luteal phase. MAIN OUTCOME MEASURE(S): Endometrial dating, pinopodes formation, immunohistochemical determination of integrins (alphavbeta3, alpha4beta1), leukemia inhibitory factor (LIF), interleukin-1 receptor type I (IL-1R tI), mouse ascites Golgi (MAG), the transmembrane mucin (MUC-1), and P4 receptor expression. RESULT(S): In 26 of 28 biopsies observers agreed; in two biopsies there was a discrepancy (difference of 72 hours). With use of LH peak, 24 of 26 samples were in phase, and 2 were 3 days behind. Pinopodes appeared on days 20-21 and persisted through day 28 in small groups or larger areas. beta3 Integrin was highly expressed in luminal and glandular epithelium from day 22 through 28; 48 hours thereafter pinopodes appeared. alpha4 Subunit exhibited luminal epithelium reaction positivity on days 22-23 and glands on days 18-23. LIF and IL-1R tI showed weak, erratic expression. MAG antibodies showed luminal epithelium expression up to day 22 and glands up to day 25. MUC-1 showed positivity during the whole luteal phase. P4 receptors were positive through day 20 and at the end of the luteal phase. CONCLUSION(S): The three most cited markers that frame the window of implantation do not correlate in our material. Pinopodes are present from day 20 on; beta3 and alpha4 integrin subunits indicate a window opening on days 22-23.


Assuntos
Implantação do Embrião , Endométrio/fisiologia , Interleucina-6 , Ciclo Menstrual/fisiologia , Adulto , Endométrio/anatomia & histologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Complexo de Golgi/imunologia , Inibidores do Crescimento/metabolismo , Humanos , Imuno-Histoquímica/métodos , Integrina alfa4beta1 , Integrinas/metabolismo , Fator Inibidor de Leucemia , Hormônio Luteinizante/sangue , Linfocinas/metabolismo , Microscopia Eletrônica de Varredura , Mucinas/metabolismo , Estudos Prospectivos , Receptores de Interleucina-1/metabolismo , Receptores Tipo I de Interleucina-1 , Receptores de Retorno de Linfócitos/metabolismo , Receptores de Progesterona/metabolismo , Receptores de Vitronectina/metabolismo , Valores de Referência
20.
Contraception ; 62(5): 231-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11172793

RESUMO

This study was designed to describe an accurate and consistent microscopic technique for the assessment of sperm number and motility in sperm-cervical mucus samples, such as those of postcoital tests (PCTs), and to identify a suitable method to extract functional spermatozoa from cervical mucus (CM). Sperm-CM preparations containing various sperm concentrations were counted using three different microscopic illuminations. The dark field-Makler technique was compared with the more classical bright field-slide technique currently used by our clinicians. Several sperm extraction techniques were applied first to bovine (BCM) and then to human (HCM) cervical mucus. Dark field microscopic illumination provided accurate, fast, and easy sperm identification. Counting variability was significantly greater with bright field-slide than with dard field-Makler, while sperm motility was always higher with this latter methodology. A high degree of agreement (intraclass correlation coefficient = 0.965) among three raters, i.e., low interobserver variability, was obtained only with dark field-Makler. Extraction procedures based on "swim-out," Percoll, trypsin, an enzyme cocktail, and mercaptoethanol resulted in small sperm yields in BCM. Mercaptoethanol and trypsin also showed poor sperm recovery in HCM. Among the protocols with the largest yields, the mechanical technique had the largest amount of residual CM, and bromelain reduced sperm motility. The extraction with dithiothreitol (DTT) showed the best results with a mean sperm recovery of 76% and enhanced sperm motility. Sperm viability as well as spontaneous and induced acrosome reaction were conserved in all techniques. In conclusion, use of the dark field-Makler counting technique in combination with DTT extraction of spermatozoa from CM samples, such as those of PCTs, would allow accurate and functional assessment of spermatozoa for preliminary contraceptive efficacy or infertility evaluation.


Assuntos
Muco do Colo Uterino , Microscopia/métodos , Espermatozoides , Feminino , Humanos , Iluminação , Masculino , Microscopia/normas , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/fisiologia
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