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1.
Andrologia ; 44(4): 265-72, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22292703

RESUMEN

Detection of activated caspases of spermatozoa could be helpful to evaluate male infertility. Although western blot is validated as a highly specific method to detect the proteins extracted from cells, the ability of this technique to detect activated sperm caspases in human semen may be limited. Indeed, round cells, which potentially contain some activated caspases, may be present in semen and interfere with the detection of activated sperm caspases. Moreover, it is necessary to evaluate the minimum amount of spermatozoa necessary to optimise the detection of activated caspases in semen samples. Our results showed that interference due to round cells contained in semen with activated caspase-3 requires separation of spermatozoa by density migration. This sperm preparation selects a mature sperm population that does not reflect the whole sperm population, and in infertile men with oligoasthenoteratozoospermia, the amount of spermatozoa thus selected is usually low. Moreover, the western blot technique's low detection sensitivity and the low level of caspase enzyme activity in human spermatozoa for activated caspase-3, -8 and -9 mean that large quantities of spermatozoa are needed to detect the expression of the activated caspases. These limitations prevent this method being used for routine analysis in clinical practice.


Asunto(s)
Caspasas/metabolismo , Semen/citología , Espermatozoides/enzimología , Espermatozoides/metabolismo , Western Blotting , Humanos , Límite de Detección , Masculino
2.
Int J Androl ; 34(6 Pt 1): 568-80, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21029115

RESUMEN

Seminal fluid inhibits sperm capacitation mainly because of its high cholesterol content. Prostasomes are the main source of cholesterol in seminal fluid. They are known to have numerous protective properties and are able to transfer proteins and lipids to spermatozoa, but their impact on capacitation and acrosome reaction (AR) is not yet well understood. The aim of this study was to determine the effects of prostasomes on human sperm capacitation and AR. After 80% Percoll selection, freshly ejaculated human spermatozoa were incubated for 3 h under capacitating conditions with prostasomes, phosphodiesterase inhibitor 3-iso-butyl-methylxantine (IBMX), or a combination of prostasomes and IBMX. Physiological concentration of prostasomes significantly decreased tyrosine phosphorylation levels of human sperm capacitation markers P110 and P80 (p < 0.01), and the proportions of capacitated (p < 0.05) and acrosome-reacted spermatozoa (p < 0.05). Prostasomes significantly increased the proportion of spermatozoa that did not incorporate propidium iodide and significantly attenuated the effect of IBMX on P110 tyrosine phosphorylation. Prostasomes had no effect on the pH(i) increase associated with capacitation. They significantly increased intracellular cAMP concentration ([cAMP](i)) and, when prostasomes and IBMX were present together, [cAMP](i) was further increased. To our knowledge, this is the first study to show clearly that prostasomes inhibit capacitation and spontaneous AR.


Asunto(s)
Semen/metabolismo , Transducción de Señal , Capacitación Espermática , Espermatozoides/fisiología , 1-Metil-3-Isobutilxantina/farmacología , Electroforesis en Gel de Poliacrilamida , Humanos , Masculino , Inhibidores de Fosfodiesterasa/farmacología , Espermatozoides/metabolismo
3.
Hum Reprod ; 25(7): 1631-42, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20472914

RESUMEN

BACKGROUND: To better understand the infertility of patients with Robertsonian translocation, the biochemical and ultrastructural apoptotic characteristics of apoptosis in the sperm of patients and fertile donors were studied. METHODS: Ejaculated sperm samples of seven Robertsonian translocation carriers and seven fertile donors were analyzed after cryopreservation. The proportion of both viable and dead spermatozoa expressing activated caspases was detected by flow cytometry through the use of different specific carboxyfluorescein-labeled caspase inhibitors. Sperm DNA fragmentation was evaluated by the TUNEL method. The percentages of intact spermatozoa or spermatozoa with ultrastructural features of apoptosis, immaturity or necrosis were estimated by electron microscopy. Meiotic segregation analysis was performed by FISH. RESULTS: Significantly lower concentration, forward motility and normal morphology of spermatozoa were found in ejaculated samples of the Robertsonian patients than fertile donors. Compared with the control group, in Robertsonian translocation carriers: (i) the caspase assays showed a significantly increased (P < 0.05) proportion of viable spermatozoa with activated poly-caspases (57.4 versus 25.8%), caspase-3 (43.5 versus 13.4%), caspase-8 (44.4 versus 17.1%) and caspase-9 (42.4 versus 10.0%); (ii) the rate of DNA fragmentation was higher (26.3 versus 12.8%); and (iii) sperm ultrastructural examination highlighted a higher percentage of immature (28.0 versus 10.0%) and apoptotic (24.5 versus 18.5%) spermatozoa. FISH study showed predominant normal/balanced spermatozoa (78.34-85.53%). CONCLUSIONS: These results show a predominant proportion of balanced and normal gametes and higher numbers of spermatozoa showing apoptosis and immaturity features in oligoasthenozoospermic Robertsonian translocation carriers than in fertile donors. This suggests defects in spermatogenesis and especially spermiogenesis of these infertile patients.


Asunto(s)
Apoptosis , Trastornos de los Cromosomas/patología , Segregación Cromosómica , Meiosis , Espermatozoides/citología , Caspasas/metabolismo , Trastornos de los Cromosomas/genética , Fragmentación del ADN , Eyaculación , Femenino , Citometría de Flujo , Heterocigoto , Humanos , Hibridación Fluorescente in Situ , Etiquetado Corte-Fin in Situ , Masculino , Motilidad Espermática/genética , Espermatozoides/ultraestructura , Translocación Genética
4.
Gynecol Obstet Fertil ; 37(6): 529-35, 2009 Jun.
Artículo en Francés | MEDLINE | ID: mdl-19481966

RESUMEN

Pro- and antioxidant are balanced in the sperm environment. Reactive Oxygen Species (ROS) are essential to the acquisition of fertilizing ability and contribute to chromatin condensation, membrane remodeling and activation of intracellular signaling pathways, during epididymal maturation, capacitation, and acrosome reaction. However, endogenous and exogenous factors can upset that balance by stimulating ROS production and/or decreasing antioxidant defenses, a situation called oxidative stress. Oxidative stress is described as a major cause of male infertility. It induces membranes and nucleus alterations, resulting in loss of mobility and decline in sperm fertilizing ability. Those are risk factors for low fertility, abnormalities of preimplantation development, and miscarriages. Various methods exist for measuring the pro- and antioxidants status of sperm, yet are little used in routine for diagnostic purposes. Meanwhile, many studies have shown the beneficial effects of oral antioxidants supplementation, or addition to semen freezing medium, to prevent in vivo and limit in vitro the deleterious effects of ROS, respectively.


Asunto(s)
Antioxidantes/uso terapéutico , Infertilidad Masculina/etiología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Espermatozoides/metabolismo , Antioxidantes/metabolismo , Humanos , Infertilidad Masculina/tratamiento farmacológico , Infertilidad Masculina/metabolismo , Masculino , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/efectos adversos , Espermatozoides/fisiología
5.
Int J Androl ; 32(3): 265-73, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18070046

RESUMEN

Staining of spermatozoa with the fluorescein-Val-Ala-Asp-fluoromethylketone has already been performed on ejaculated sperm samples, using fluorescence microscopy (FM) or flow cytometry (FCM) in order to score activated caspases. This assay may help in assessing apoptosis and its role in male fertility. The present study compares the above two techniques in order to adopt the most accurate method for detection in human frozen-thawed testicular, epididymal and ejaculated spermatozoa. The analyses were carried out on frozen/thawed testicular (n = 14), epididymal (n = 8) and ejaculated (n = 10) sperm samples. Activated caspases were detected in living spermatozoa using fluorescein-labelled inhibitors of poly-caspases (FLICA). For the measurements by FM, the same-observer and different-observer reliability were assessed in testicular and epididymal sperm samples. The inter-method (FM and FCM) reliability was assessed both in epididymal and ejaculated sperm samples. The reliability was evaluated by intraclass correlation coefficient (ICC) and the differences between paired measurements from the same sample were tested by Wilcoxon test for matched pairs. For the same-observer and the different-observer data, the ICC were 0.980 and 0.986. In testicular suspensions, the presence of different types of germinal and somatic cells hampers the differentiation of stained spermatozoa by FCM. For the inter-method reliability, the ICC was 0.903. A lower proportion of the viable spermatozoa stained with FLICA was observed by using FM (-6.60 +/- 7.38 %, mean +/- SD; p = 0.003) compared with FCM. To measure the proportion of spermatozoa with activated caspases by this test, FM is a highly accurate and reliable method whatever the sperm origin (ejaculate, epididymis, and testis). FCM cannot be used for testicular samples but seems to be more appropriate for analysis of epididymal and ejaculated sperm samples. The systematic lower proportion by FM in measuring the proportion of stained viable spermatozoa with FLICA involves that only the data measured by the same method (FM or FCM) may be compared.


Asunto(s)
Caspasas/análisis , Citometría de Flujo/métodos , Microscopía Fluorescente/métodos , Espermatozoides/enzimología , Adulto , Azoospermia/patología , Activación Enzimática , Epidídimo/citología , Congelación , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Coloración y Etiquetado , Testículo/citología
6.
Hum Reprod ; 22(2): 380-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17092986

RESUMEN

BACKGROUND: Cryopreservation/thawing of bovine spermatozoa induces a reduction in cell viability and is possibly associated with a form of programmed cell death that we previously named 'apoptosis-like phenomenon'. METHODS: In this study, we specified, by flow cytometry, the moment of appearance of some characteristics of apoptosis during the cryopreservation process. We also studied the presence and/or activation in bovine sperm cells of specific proteins involved in somatic cell apoptosis by western blot and fluorimetry. RESULTS: A decrease of the mitochondrial membrane potential (DeltaPsim) was detectable 5 min after sperm dilution in the cryopreservation medium, caspase activation after 3 h of equilibration and an increase in plasma membrane permeability after the complete process of cryopreservation/thawing. The presence of the pro-apoptotic factor Bax, a protein that facilitates the formation of mitochondrial pores, was observed in bovine spermatozoa, but the anti-apoptotic factor Bcl-2 was not detectable. Moreover, it was observed that bovine spermatozoa contain cytochrome c and apoptosis-inducing factor (AIF), two proteins usually released from the mitochondria during the apoptotic process. Activated caspase-9, involved in the mitochondrial pathway, was detected in bovine spermatozoa but not caspase-3 and -8. CONCLUSIONS: The early features of apoptosis appear as ordered events during the cryopreservation/thawing process of bovine sperm cells. Bovine spermatozoa contain the machinery necessary to proceed to apoptosis involving especially the mitochondrial pathway.


Asunto(s)
Apoptosis/fisiología , Criopreservación , Preservación de Semen/efectos adversos , Reacción Acrosómica , Animales , Factor Inductor de la Apoptosis/metabolismo , Caspasa 3/metabolismo , Caspasa 8/metabolismo , Caspasa 9/metabolismo , Bovinos , Supervivencia Celular , Citocromos c/metabolismo , Citometría de Flujo , Humanos , Cinética , Masculino , Fosfolípidos/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Espermatozoides/metabolismo , Células U937 , Proteína X Asociada a bcl-2/biosíntesis
7.
Andrologia ; 36(6): 370-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15541053

RESUMEN

This study, performed using semen samples from 10 men, investigated the relationship between sperm protein tyrosine phosphorylation and acrosomal status in conditions supporting in vitro capacitation. Percoll-selected spermatozoa (cells from the 95% fraction) were incubated for 3 h at 37 degrees C under an atmosphere of 5% CO2 in air, in a polyvinyl alcohol (1 mg ml(-1)) containing Biggers-Whitten-Whittingham's medium, nonsupplemented or supplemented with either bovine serum albumin (BSA; fatty acid free, 3 mg ml(-1)) or 2-hydroxy-propyl-beta-cyclodextrin (2-OH-p-beta-CD; 0.5, 1, 2 mmol l(-1)). Sperm suspension in each medium was split into two aliquots. The first was used to evaluate the acrosomal status by staining with the fluorescein isothiocyanate Pisum sativum agglutinin after induction of the acrosome reaction (AR) for 45 min with 10 micromol l(-1) of A23187 calcium ionophore. The second aliquot was used for sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting, followed by a densitometric analysis. Compared with the nonsupplemented medium, BSA- or 2-OH-p-beta-CD-supplementation induced an increase in both the percentage of live acrosome-reacted sperm and the tyrosine phosphorylation intensity of the main phosphorylated 107 kDa protein. A correlation between the percentage of live acrosome-reacted sperm and the 107-kDa protein phosphotyrosine intensity was observed. Therefore, the 107 kDa protein-phosphotyrosine level measurement would bring additional information to conventional semen parameters in the assessment of the human sperm functionality.


Asunto(s)
Reacción Acrosómica , Calcimicina/farmacología , Ionóforos/farmacología , Proteínas/metabolismo , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Tirosina/metabolismo , 2-Hidroxipropil-beta-Ciclodextrina , Reacción Acrosómica/efectos de los fármacos , Humanos , Masculino , Peso Molecular , Fosforilación/efectos de los fármacos , Proteínas/química , Albúmina Sérica Bovina/farmacología , beta-Ciclodextrinas/farmacología
8.
Int J Androl ; 24(6): 327-34, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11737413

RESUMEN

In this work, we examined whether spermatozoa (spz) from normospermic fertile patients and selected by a swim-up (S-U) procedure had a particular membrane fluidity related to their maturity and their lipid content as compared with the sperm cells from the whole ejaculate (total sperm). Swim-up selected sperm had a reduced cytoplasmic space as revealed by a lower creatine kinase (CK) activity compared with total sperm (2 +/- 1 vs. 12 +/- 5 mUI/10(7) spz, p < 0.05). The cholesterol (Chol) and total phospholipid (PL) contents were significantly lower in S-U selected sperm than in total sperm (0.72 +/- 0.08 vs. 1.20 +/- 0.30 nmol/10(6) spz for Chol and 1.77 +/- 0.17 vs. 2.78 +/- 0.50 nmol/10(6) spz for PL, p < 0.05) and such a decrease was observed for the three major membrane PL: phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM). However, these decreases were not associated with a change in either Chol/PL or PC/(PC + PE) molar ratios. Membrane fluidity estimated by fluorescence polarization remained comparable between the S-U sperm fraction and total sperm (fluorescence polarization anisotropy, r, which is inversely proportional to the fluidity: 0.235 +/- 0.006 vs. 0.230 +/- 0.005). The sperm membrane fluidity obtained in normospermic patients was compared with abnormospermic ones (oligoasthenoteratospermia). In abnormospermic patients, the membrane fluidity was decreased in migrated spermatozoa compared with total sperm (anisotropy: 0.210 +/- 0.010 vs. 0.250 +/- 0.013, p < 0.01). Our data suggest that the S-U method selected a subpopulation of mature spermatozoa characterised by a low content of Chol and PL, likely related to a reduced membrane area. The fact that Chol/PL and PC/(PC + PE) molar ratios were unchanged shows a maintenance of the membrane quality. This was confirmed by the fluorescence anisotropy measurement showing no difference in plasma membrane fluidity between S-U selected sperm and total sperm. In abnormal semen the migrated spermatozoa had a lower fluidity compared with total sperm suggesting a defective sperm function. These results bring new elements characterizing the S-U selected spermatozoa.


Asunto(s)
Fluidez de la Membrana , Lípidos de la Membrana/metabolismo , Espermatozoides/fisiología , Cromatografía Líquida de Alta Presión , Creatina Quinasa/metabolismo , Humanos , Masculino , Espectrometría de Fluorescencia , Espermatozoides/enzimología , Espermatozoides/metabolismo
9.
J Chromatogr A ; 935(1-2): 259-65, 2001 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-11762778

RESUMEN

A simple, rapid and accurate method to separate and quantify cholesterol, desmosterol and cholesterol sulfate in human spermatozoa and seminal plasma (SP) is described. This high-performance liquid chromatographic procedure is based on reversed-phase chromatography on a Inertsil ODS2 5 microm silica column with a binary gradient of mixtures of chloroform-methanol and chloroform-methanol-water as the mobile phase at a flow-rate of 0.25 ml/min. Sterols are separated with good resolution and high reproducibility. The eluted sterols are quantified using a light-scattering (mass) detector. As little as 64, 64 and 68 pmol of cholesterol, desmosterol and cholesterol sulfate, respectively, can be quantified under these conditions. Cholesterol is the predominant sterol both in spermatozoa (107+/-7 nmol/10(8) spermatozoa) and SP (0.83+/-0.10 micromol/ml) whereas the concentrations of desmosterol were 38+/-6 nmol/10(8) in spermatozoa and 0.18+/-0.02 micromol/ml in SP. Cholesterol sulfate represents about 6% of total cholesterol in the spermatozoa and SP. In conclusion, this method offers interesting perspectives for the quantitative analysis of these sterols not only in semen, but also in other biological samples.


Asunto(s)
Ésteres del Colesterol/análisis , Colesterol/análisis , Cromatografía Líquida de Alta Presión/métodos , Desmosterol/análisis , Semen/química , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados
10.
Hum Reprod ; 15(10): 2160-4, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11006192

RESUMEN

Semen cryopreservation is an important procedure in the treatment of human infertility. However, the ability of spermatozoa to survive freeze/thaw processes varies between patients. Cryopreservation-induced stress may result in membrane injury with consequent loss of sperm motility and viability. We investigated the relationship between the physico-chemical state of the human sperm membranes and their tolerance to cryopreservation. Conventional characteristics of 20 semen samples were analysed before and after cryopreservation as well as their membrane fluidity assessed by measuring the fluorescence polarization anisotropy, which is inversely proportional to the fluidity. Correlation between fluidity and post-thaw recoveries of motile and viable spermatozoa were examined. Results showed that membrane anisotropy markedly varies between patients. In cryopreserved spermatozoa, anisotropy values were significantly higher than in fresh spermatozoa. Furthermore, recovery of motile and viable spermatozoa after freeze/thaw was strongly correlated with anisotropy of fresh spermatozoa (P < 0.05). The higher the membrane fluidity was before freezing, the better was the response of spermatozoa to cryopreservation. The results indicate that the freeze/thaw process results in a rigidifying effect on the sperm membrane and suggest that sperm adaptability to freeze/thaw-induced stress could be dependent on their initial membrane fluidity. The latter finding has practical implications for predicting the response of spermatozoa following freezing and thawing and for improving the recovery of viable spermatozoa.


Asunto(s)
Membrana Celular/química , Criopreservación/métodos , Fluidez de la Membrana/fisiología , Preservación de Semen/métodos , Espermatozoides/fisiología , Membrana Celular/fisiología , Humanos , Masculino , Valor Predictivo de las Pruebas , Semen/fisiología , Motilidad Espermática
11.
Mol Hum Reprod ; 6(10): 883-91, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11006316

RESUMEN

Prostasomes are particular lipid vesicles secreted by the prostate in human semen and involved in several physiological functions such as the improvement of sperm motility or immunomodulation. We have previously shown that they reduced the overall reactive oxygen species (ROS) production of seminal polymorphonuclear neutrophils (PMN). The present study was conducted to define the mechanism by which prostasomes inhibit the ROS production of blood and seminal PMN. The luminol chemiluminescence measuring total ROS production of blood PMN stimulated by either a phorbol ester (PMA) or a chemoattractant peptide, formyl-Met-Leu-Phe (fMLP) was significantly inhibited by prostasomes. The NADPH oxidase activity of the PMN was measured by 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1, 2-a]pyrazin-3-one (MCLA) chemiluminescence. Prostasomes inhibited the NADPH oxidase activity of blood or seminal PMN and increased the lag-phase of the enzyme after PMA stimulation. Prostasomes also inhibited significantly the NADPH oxidase activity of fMLP stimulated blood PMN, but the inhibition was not significant for seminal PMN. The lipid composition of blood PMN was analysed and compared to the lipid composition of prostasomes. This showed that prostasomes had a high cholesterol:phospholipid molar ratio and a high proportion of sphingomyelin. Together with the fact that prostasomes can rigidify the plasma membrane of blood PMN, these results led us to postulate that prostasomes inhibit the NADPH oxidase activity of PMN by lipid transfer from the prostasomes to the plasma membrane of the PMN.


Asunto(s)
NADPH Oxidasas/antagonistas & inhibidores , Neutrófilos/enzimología , Próstata/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Vesículas Secretoras/metabolismo , Semen/química , Colesterol/metabolismo , Colorantes Fluorescentes , Humanos , Imidazoles , Mediciones Luminiscentes , Masculino , Fluidez de la Membrana , N-Formilmetionina Leucil-Fenilalanina/farmacología , NADPH Oxidasas/sangre , NADPH Oxidasas/metabolismo , Neutrófilos/efectos de los fármacos , Fosfolípidos/sangre , Fosfolípidos/metabolismo , Próstata/química , Pirazinas , Espermatozoides/metabolismo , Temperatura , Acetato de Tetradecanoilforbol/farmacología
12.
J Chromatogr B Biomed Sci Appl ; 740(1): 101-7, 2000 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-10798299

RESUMEN

A high-performance liquid chromatographic method coupled with light-scattering detection for the separate and accurate quantification of cholesterol and main phospholipid classes was applied to human spermatozoa and seminal plasma (SP). This method is based on normal-phase chromatography with silica gel as stationary phase and a ternary gradient with hexane, mixtures of chloroform-methanol and water as mobile phase. Lipids are separated with a good resolution and a high reproducibility. About 5 x 10(6) spermatozoa or 25 microl of seminal plasma are sufficient to accurate quantitative analysis of phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), phosphatidycholine (PC), sphingomyelin (SM) and cholesterol. PC is the predominant phospholipid class in spermatozoa (102+/-8 nmol/10(8) spermatozoa) whereas SM is the major in the SP (163+/-6 nmol/ml). Both in spermatozoa and SP, PI is the minor class of the phospholipids (12+/-1 nmol/10(8) spermatozoa and 24+/-2 nmol/ml). In conclusion, this method offers interesting perspectives for analysis of sperm lipid composition in semen samples with low quantities of spermatozoa.


Asunto(s)
Colesterol/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Fosfolípidos/aislamiento & purificación , Semen/química , Humanos , Luz , Masculino , Dispersión de Radiación , Espermatozoides/química
13.
Int J Androl ; 22(3): 190-6, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10367240

RESUMEN

The objective was to evaluate the efficiency of a biological material-free medium and the role of seminal plasma (SP) in the cryopreservation of human spermatozoa. Normal semen samples and low-quality semen samples were used for this study. After centrifugation of 300 microL fractions of whole semen, pellets were resuspended either in autologous SP or in a chemically defined medium (BM) supplemented or not with 3% bovine serum albumin (BSA); after 15 min at 37 degrees C, the samples were diluted (V/V) with cryoprotective medium (30 mM NaCl; 22 mM sodium citrate, 19.4 mM fructose; 80 mM glutamine; 14%, V/V, glycerol) and maintained for 15 min at room temperature before freezing. Assessment of viability and motility was performed using fresh semen (T0), after centrifugation and resuspension prior to adding the cryoprotectant (T15), after adding the cryoprotectant (T30) and after freezing and thawing (Tpost). In all three resuspending media used, sperm viability and motility (forward and total) decreased (p < 0.05) during both the equilibration period especially before addition of the cryoprotective medium (between T0 and T15) and during the freeze-thaw process comparison between T30 and Tpost. The recovery of viable and motile spermatozoa (post-thaw values/values of fresh samples) was higher (p < 0.05) in normal semen than in low-quality semen. In both groups, the recovery was slightly, but significantly, higher with SP than with BM and the presence of BSA has no beneficial effect. To conclude, these data suggest that SP may reduce the deleterious effects of cryopreservation. Nevertheless cryopreservation of spermatozoa in a medium containing neither SP nor biological substances could offer an acceptable cryoprotection of spermatozoa to be used in assisted fertilization procedures, especially for intracytoplasmic sperm injection.


Asunto(s)
Criopreservación , Crioprotectores , Infertilidad Masculina , Preservación de Semen , Semen/fisiología , Espermatozoides/fisiología , Animales , Bovinos , Centrifugación , Criopreservación/métodos , Humanos , Masculino , Motilidad Espermática
14.
Mol Hum Reprod ; 5(6): 587-93, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10341008

RESUMEN

The present study was undertaken to evaluate the frequency and nature of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene in infertile patients undergoing intracytoplasmic sperm injection. A total of 90 patients were screened for a panel of 10 mutations in the CFTR gene frequently involved in congenital absence of the vas deferens (CAVD); the patients included 14 with azoospermia and CAVD, 39 patients with azoospermia without CAVD (n = 39) and 37 patients with severe oligozoospermia. The length of the polymorphic polypyrimidine tract (allele 5T, 7T and 9T) in the intron 8/exon 9 splice-acceptor site was also determined. In 10 out of 14 patients with CAVD, CFTR mutations were found; nine patients had one DeltaISOdiaDeltaF508 mutation and one patient had two CFTR mutations (N1303K/R117H). Allele 5T was present in eight of these patients. In six patients, 5T was the non-DeltaISOdiaDeltaF508 allele and in two patients there was no known CFTR mutation. None of the CFTR mutations were observed in patients with azoospermia without CAVD or with severe oligozoospermia and the frequency of allele 5T was 3.6% (three out of 78 alleles) and 1.35% (one out of 74 alleles) respectively. Our observation suggests that the CFTR gene is not involved in either spermatogenesis or in the pathology of the genital tract, except for CAVD.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Fertilización In Vitro/métodos , Pruebas Genéticas , Infertilidad Masculina/genética , Mutación , Adulto , Humanos , Inyecciones , Masculino , Oligospermia/genética , Espermatozoides , Conducto Deferente/anomalías
15.
Hum Reprod ; 13(11): 3108-13, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9853866

RESUMEN

Oxygen radical generation is known to be detrimental to sperm function. An example of a reactive oxygen species-associated male pathology is oligozoospermia in which fertilization and pregnancy rates are low in in-vitro fertilization (IVF) programmes. As the extent of the modifications induced by reactive oxygen species (ROS) depends on several factors, notably from oxygen tension in the incubation medium, the aim of this study was to examine the influence of a low (5%) rather than atmospheric (20%) oxygen tension in the incubator gas phase on the function of Percoll-selected spermatozoa from ejaculates of oligozoospermic patients and normozoospermic fertile donors. After incubation for several hours in a gas phase of either 5% CO2/90% N2/5% O2 or 5% CO2/95% air (20% O2), none of the parameters investigated, e.g. movement characteristics, potential of spermatozoa to acquire hyperactivated motility, to undergo the acrosome reaction when challenged with a calcium ionophore and to fuse with zona-free hamster oocytes, was significantly different between the two oxygen tensions in fertile donors. In contrast, among oligozoospermic patients, the motility parameters, the percentage of hyperactivated motility and of induced-acrosome reaction were significantly improved under a gas phase of 5% O2 compared with those observed under an atmosphere of 20% O2 (P < 0.05). Exposure to 5% rather than 20% oxygen tension also induced a significant increase in the percentage of penetration of zona-free hamster eggs after capacitation for 17 h, but no difference was found in the mean number of bound spermatozoa per oocyte. After incubation for 24 h, a significantly higher survival rate was observed under 5% compared with 20% oxygen tension. These results show that the use of a low oxygen tension rather than air might improve spermatozoan competence of oligozoospermic patients during IVF programmes.


Asunto(s)
Oligospermia/fisiopatología , Oxígeno/administración & dosificación , Espermatozoides/fisiología , Reacción Acrosómica/efectos de los fármacos , Animales , Cricetinae , Femenino , Humanos , Masculino , Oligospermia/patología , Oocitos/fisiología , Especies Reactivas de Oxígeno/metabolismo , Capacitación Espermática , Motilidad Espermática/efectos de los fármacos , Interacciones Espermatozoide-Óvulo/efectos de los fármacos , Espermatozoides/efectos de los fármacos
16.
Mol Hum Reprod ; 4(7): 667-72, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9701789

RESUMEN

Prostasomes are human-specific lipid vesicles originating from the prostate and present in seminal plasma. They are involved in a number of biological functions such as sperm motility and immunomodulation by seminal plasma. The aim of our study was to investigate whether prostasomes play a role in the antioxidant status of seminal plasma. In cell suspensions obtained after elimination of seminal plasma by centrifugation, reactive oxygen species (ROS) as measured by luminol-enhanced chemiluminescence were mainly produced by polymorphonuclear neutrophils (PMN). The addition of prostasomes to these cell suspensions lowered the overall ROS production in the basal state and after stimulation with phorbol ester. This action could not be explained by a ROS-scavenging capacity of the prostasomes, as demonstrated by their inability to scavenge ROS produced by 2,2'-azobis-2-amidinopropane dihydrochloride. Using electron spin resonance, we could assess the influence of prostasomes on the plasma membranes of blood PMN and show that it was characterized by an increase in the correlation-relaxation time of the probe 16-doxyl-stearic acid inserted in the membranes. Thus, prostasomes caused a rigidification of blood PMN membranes. These results strongly suggest that the effect of prostasomes in semen could result from their interaction with PMN.


Asunto(s)
Antioxidantes/metabolismo , Orgánulos/metabolismo , Próstata/metabolismo , Semen/citología , Membrana Celular/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Técnicas In Vitro , Mediciones Luminiscentes , Luminol , Masculino , Neutrófilos/metabolismo , Próstata/citología , Especies Reactivas de Oxígeno/metabolismo , Semen/metabolismo , Motilidad Espermática
17.
Andrologia ; 30(2): 71-8, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9629426

RESUMEN

Unstimulated macrophages from testes inhibited the production of testosterone by Leydig cells from adult, but not immature, Sprague-Dawley rats (significant after 48 h). Similar results were observed with unstimulated macrophage-conditioned media, suggesting that the observed effect was mediated by one or more secretory products. None of these substances was interleukin-1, since macrophage supernatants tested negative in an interleukin-1 alpha and interleukin-1 beta sensitive, thymocyte assay. Interleukin-6 was detected by a B cell proliferation assay. After stimulation by LPS, testicular macrophages enhanced testosterone production by Leydig cells from adult and immature rats. This enhancement was dose-dependent and required low concentrations (but over 2.5%) of conditioned media. Interleukin-1 and interleukin-6 activities were detected in LPS-stimulated macrophage supernatants. Supernatants of LPS-stimulated, human monocytes had similar effects on Leydig cells. They were rich in interleukin-1, interleukin-1 receptor antagonist and interleukin-6. The present study suggests that, in adult rats, testicular macrophages modulate Leydig cell steroidogenesis by secretory products whose secretion depends on the physiological state of macrophages. The factor or factors responsible for stimulation are not species-specific. The effect cannot be accounted for by variations in the concentration of the above mentioned interleukins in macrophage supernatants.


Asunto(s)
Células Intersticiales del Testículo/metabolismo , Macrófagos/fisiología , Testosterona/biosíntesis , Animales , Células Cultivadas , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-1/farmacología , Interleucina-6/farmacología , Lipopolisacáridos/farmacología , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Interleucina-1/antagonistas & inhibidores , Sialoglicoproteínas/farmacología
18.
Fertil Steril ; 68(3): 542-4, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9314931

RESUMEN

OBJECTIVE: To assess whether sperm recovered from postejaculatory urine and cryopreserved can be used successfully for intracytoplasmic sperm injection (ICSI). DESIGN: Case report. SETTING: Laboratory of Developmental and Reproductive Biology, University Hospital. PATIENT(S): A couple with male infertility resulting from complete retrograde ejaculation. INTERVENTION(S): Freezing of sperm recovered from urine and subsequent use for ICSI. MAIN OUTCOME MEASURE(S): Survival, maintenance of fertilization, and pregnancy potential of sperm recovered from urine and cryopreserved. RESULT(S): On thawing, the sperm were still alive (32% viability) and very slightly motile (2% sluggish motility). Of 16 oocytes injected, 10 (62.5%) produced normal, cleaving embryos. A twin pregnancy with the birth of two healthy infant girls was achieved after the transfer of three embryos. CONCLUSION(S): The birth of normal, healthy female infants after ICSI with sperm recovered from postejaculatory urine and then cryopreserved demonstrates the usefulness of freezing such sperm even if motility is very low, to avoid surgery in the patient.


Asunto(s)
Criopreservación , Eyaculación , Infertilidad Masculina/terapia , Inseminación Artificial Homóloga , Espermatozoides , Adulto , Citoplasma , Femenino , Humanos , Recién Nacido , Inyecciones , Masculino , Embarazo
19.
Prog Urol ; 7(3): 496-504, 1997 Jun.
Artículo en Francés | MEDLINE | ID: mdl-9273081

RESUMEN

The laboratory investigation of male fertility is based on semen examinations and allows assessment of all events occurring between the onset of spermatogenesis and ejaculation. The sperm count and semen cytology remain the first-line examinations, but can be completed by more specific examinations allowing assessment of spermatozoan functions involved in passage along the female genital tract and penetration of the oocyte. However, apart from azoospermia, there is no absolute criterion beyond which semen can be considered to be infertile. The results must be interpreted by taking into account all these examinations which can provide element concerning the aetiology of infertility, helping to guide subsequent treatment. When the use of various in vivo treatments has failed, patients may require medically-assisted procreation (MAP) techniques. The type of MAP chosen will depend on the characteristics of the semen and the functional capacities of the spermatozoa.


Asunto(s)
Fertilidad/fisiología , Espermatozoides/fisiología , Eyaculación/fisiología , Femenino , Genitales Femeninos/fisiología , Humanos , Infertilidad Masculina/etiología , Infertilidad Masculina/terapia , Masculino , Oligospermia/complicaciones , Oocitos/citología , Oocitos/fisiología , Técnicas Reproductivas , Semen/química , Semen/citología , Semen/fisiología , Capacitación Espermática/fisiología , Recuento de Espermatozoides , Motilidad Espermática/fisiología , Interacciones Espermatozoide-Óvulo/fisiología , Espermatogénesis/fisiología , Espermatozoides/citología
20.
Arch Androl ; 38(3): 207-14, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9140617

RESUMEN

An experiment was carried out to analyze the effect of 3 days of starvation on the Leydig cell function in adult rats. Starvation markedly decreased plasma insulin and testosterone levels (p < .05). The weight of testes was maintained, whereas the testicular interstitial fluid volume decreased (p < .05). The level of testosterone decreased in this fluid (60%), whereas insulin levels showed no significant change. Purified Leydig cells showed normal LH/hCG binding in fasted rats but low insulin binding. The ability of these cells to produce testosterone in vitro was normal under both basal conditions and hCG stimulation in the absence and presence of insulin in the incubation medium. These data suggest that there is no gross impediment in the Leydig cell capacity to produce testosterone that might explain the starvation-associated decrease in plasma testosterone.


Asunto(s)
Células Intersticiales del Testículo/fisiología , Inanición/fisiopatología , Animales , Líquidos Corporales/fisiología , Células Cultivadas , Hormonas/sangre , Insulina/fisiología , Células Intersticiales del Testículo/metabolismo , Masculino , Ratas , Ratas Wistar , Receptor de Insulina/metabolismo , Receptores de HL/metabolismo , Inanición/metabolismo , Testículo/citología , Testículo/fisiología , Testosterona/biosíntesis
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