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1.
PLoS One ; 15(11): e0241181, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33180820

RESUMO

The acrosome reaction (AR) is a strictly-regulated, synchronous exocytosis that is required for sperm to penetrate ova. This all-or-nothing process occurs only once in the sperm lifecycle through a sequence of signaling pathways. Spontaneous, premature AR therefore compromises fertilization potential. Although protein kinase A (PKA) pathways play a central role in AR across species, the signaling network used for AR induction is poorly understood in birds. Mechanistic studies of mammalian sperm AR demonstrate that PKA activity is downstreamly regulated by Src family kinases (SFKs). Using SFK inhibitors, our study shows that in chicken sperm, SFKs play a role in the regulation of PKA activity and spontaneous AR without affecting motility. Furthermore, we examined the nature of SFK phosphorylation using PKA and protein tyrosine phosphatase inhibitors, which demonstrated that unlike in mammals, SFK phosphorylation in birds does not occur downstream of PKA and is primarily regulated by calcium-dependent tyrosine phosphatase activity. Functional characterization of SFKs in chicken sperm showed that SFK activation modulates the membrane potential and plays a role in inhibiting spontaneous AR. Employing biochemical isolation, we also found that membrane rafts are involved in the regulation of SFK phosphorylation. This study demonstrates a unique mechanism for regulating AR induction inherent to avian sperm that ensure fertilization potential despite prolonged storage.


Assuntos
Acrossomo/fisiologia , Galinhas/metabolismo , Galinhas/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/metabolismo , Espermatozoides/fisiologia , Quinases da Família src/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Masculino , Microdomínios da Membrana/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Motilidade Espermática/fisiologia
2.
PLoS One ; 15(11): e0240689, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33147280

RESUMO

With increased population and urban development, there are growing concerns regarding health impacts of environmental noise. We assessed the relationship between nighttime environmental noise and semen quality of men who visited for fertility evaluation. This is a retrospective cohort study of 1,972 male patient who had undertaken semen analysis between 2016-2018 at a single fertility center of Seoul, South Korea. We used environmental noise data of National Noise Information System (NNIS), Korea. Using semiannual nighttime noise measurement closest to the time of semen sampling, individual noise exposures at each patient's geocoded address were estimated with empirical Bayesian kriging method. We explored the association between environmental noise and semen quality indicators (volume, concentration, % of progressive motility, vitality, normal morphology, total motile sperm count, oligozoospermia, asthenozoospermia, and severe teratozoospermia) using multivariable regression and generalized additive models. Estimated exposure to nighttime environmental noise level in the study population was 58.3±2.2 Leq. Prevalence of oligozoospermia, asthenozoospermia, and severe teratozoospermia were 3.3%, 14.0%, and 10.1%. Highest quartile nighttime noise was associated with 3.5 times higher odds of oligozoospermia (95% CI: 1.18, 10.17) compared to lowest quartile. In men whose noise exposure is in 3rd quartile, odds ratio (OR) of severe teratozoospermia was 0.57 (95% CI: 0.33, 0.98). The OR for 4th quartile noise were toward null. In generalized additive model, the risk of oligozoospermia increases when the nighttime noise is 55 Leq dB or higher. Our study adds an evidence of potential impact of environmental noise on semen quality in men living in Seoul. Additional studies with more refined noise measurement will confirm the finding.


Assuntos
Fertilidade/fisiologia , Ruído , Análise do Sêmen/métodos , Sêmen/fisiologia , Espermatozoides/fisiologia , Adulto , Astenozoospermia/diagnóstico , Astenozoospermia/epidemiologia , Astenozoospermia/fisiopatologia , Teorema de Bayes , Estudos de Coortes , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/fisiopatologia , Masculino , Oligospermia/diagnóstico , Oligospermia/epidemiologia , Oligospermia/fisiopatologia , Prevalência , Sêmen/citologia , Seul/epidemiologia , Contagem de Espermatozoides , Motilidade Espermática/fisiologia
3.
Sci Rep ; 10(1): 17143, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051512

RESUMO

Microfluidics is proposed as a technique for efficient sperm sorting, to achieve the ultimate goal of resolving infertility problems in livestock industry. Our study aimed to design a microfluidic sperm-sorting device (SSD) through a high-efficacy and cost- and time-effective fabrication process, by using COMSOL Multiphysics simulation and modeling software, and the design of experiment (DOE) method. The eight factors affecting SSD performance were established. The simulation was then run, and statistically significant factors were analyzed. Minitab16 was used to optimize the design modulus factor. By setting the statistical significance at p < 0.05, the factors affecting experimental structure were analyzed. At a desirability of 97.99, the optimal parameters for the microfluidic chip were: angle between sperm and medium inlet chambers (A = 43°), sperm inlet flow rate (B = 0.24 µL min-1), medium inlet flow rate (C = 0.34 µL min-1), and inlet and outlet chamber lengths (D = 5000 µm). These optima were then applied to microfluidics device construction. The device was produced using soft lithographic microfabrication techniques and tested on Holstein-Friesian bull sperm. The highest bull sperm-sorting performance for this microfluidic device prototype was 96%. The error between the simulation and the actual microfluidic device was 2.72%. Fluid viscosity ranges analysis-based simulations revealed acceptable fluid viscosity tolerances for the SSD. The simulation results revealed that the acceptable tolerance range for fluid viscosity was 0.00001-0.003 kg m-1 s-1. This optimally designed microfluidic chip-based SSD may be integrated into sperm x/y separation micro devices.


Assuntos
Separação Celular/instrumentação , Desenho de Equipamento/instrumentação , Microfluídica/instrumentação , Animais , Bovinos , Infertilidade/terapia , Dispositivos Lab-On-A-Chip , Gado/fisiologia , Masculino , Técnicas Analíticas Microfluídicas/instrumentação , Motilidade Espermática/fisiologia , Espermatozoides/citologia
4.
Sci Rep ; 10(1): 15619, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32973195

RESUMO

Previously we demonstrated that multidrug resistance-associated protein 4 transporter (MRP4) mediates cAMP efflux in bovine spermatozoa and that extracellular cAMP (ecAMP) triggers events associated to capacitation. Here, we deepen the study of the role of MRP4 in bovine sperm function by using MK571, an MRP4 inhibitor. The incubation of spermatozoa with MK571 during 45 min inhibited capacitation-associated events. MRP4 was localized in post-acrosomal region and mid-piece at 15 min capacitation, while at 45 min it was mainly located in the acrosome. After 15 min, MK571 decreased total sperm motility (TM), progressive motility (PM) and several kinematic parameters. The addition of ecAMP rescued MK571 effect and ecAMP alone increased the percentage of motile sperm and kinematics parameters. Since actin cytoskeleton plays essential roles in the regulation of sperm motility, we investigated if MRP4 activity might affect actin polymerization. After 15 min capacitation, an increase in F-actin was observed, which was inhibited by MK571. This effect was reverted by the addition of ecAMP. Furthermore, ecAMP alone increased F-actin levels while no F-actin was detected with ecAMP in the presence of PKA inhibitors. Our results support the importance of cAMP efflux through MRP4 in sperm capacitation and suggest its involvement in the regulation of actin polymerization and motility.


Assuntos
Acrossomo/fisiologia , Actinas/fisiologia , AMP Cíclico/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Capacitação Espermática , Motilidade Espermática/fisiologia , Animais , Bovinos , Masculino , Fosforilação , Transdução de Sinais
5.
Life Sci ; 258: 118242, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32784056

RESUMO

AIMS: As the spermatogenesis process is targeted by cisplatin (Cis) that changes testicular morphology, alters sperm quality, and hence causes male infertility. This study investigated the possible therapeutic effects of l-carnitine (LC) on Cis impaired spermatogenesis's establishment during the prepubertal phase. MATERIALS AND METHODS: Ninety-six prepubertal Sprague Dawley male rats were divided into four groups. CONTROL GROUP: rats were injected with 0.9% saline solution intraperitoneally (i.p.). LC group: animals were injected for eight weeks, with 250 mg/kg/wk. LC (i.p.). Cis group: animals were injected with a single dose of 5 mg/kg Cis (i.p.). LC + Cis group: animals were pre-injected with LC 250 mg/kg 2 h before Cis injection. The rats were sacrificed at 37, 60, and 90 days old, and their testes were taken for biochemical, molecular, and histopathological studies. The motility, viability, morphology, and DNA fragmentation of sperm in adult rats were also measured. KEY FINDINGS: Group treated with LC and Cis showed an increase in antioxidant and hormonal activity compared to the Cis treated group in the pre and post-pubertal period. Moreover, there was an increase in sperm survival, motility, and DNA integrity. Furthermore, LC showed an increase in the anti-apoptotic and chromatin remodeling genes and a decrease in the pro-inflammatory genes. SIGNIFICANCE: LC could enhance the spermatogenesis process after exposure to Cis during the prepubertal phase by restoring the balance between reactive oxygen species and antioxidant activity, improving hormonal activity, sperm quality and DNA integrity, promoting protamination and blood-testis barrier integrity, and maintaining the testicular architecture.


Assuntos
Carnitina/farmacologia , Cisplatino/toxicidade , Infertilidade Masculina/prevenção & controle , Infertilidade Masculina/fisiopatologia , Maturidade Sexual/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Animais , Antineoplásicos/toxicidade , Carnitina/uso terapêutico , Infertilidade Masculina/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia , Motilidade Espermática/efeitos dos fármacos , Motilidade Espermática/fisiologia , Espermatogênese/fisiologia
6.
Exp Anim ; 69(4): 374-381, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32554934

RESUMO

Infertility is a global health issue that affects 1 in 6 couples, with male factors contributing to 50% of cases. The flagellar axoneme is a motility apparatus of spermatozoa, and disruption of its structure or function could lead to male infertility. The axoneme consists of a "9+2" structure that contains a central pair of two singlet microtubules surrounded by nine doublet microtubules, in addition to several macromolecular complexes such as dynein arms, radial spokes, and nexin-dynein regulatory complexes. Molecular components of the flagellar axoneme are evolutionally conserved from unicellular flagellates to mammals, including mice. Although knockout (KO) mice have been generated to understand their function in the formation and motility regulation of sperm flagella, the majority of KO mice die before sexual maturation due to impaired ciliary motility, which makes it challenging to analyze mature spermatozoa. In this review, we introduce methods that have been used to overcome premature lethality, focusing on KO mouse lines of central pair components.


Assuntos
Axonema/fisiologia , Cauda do Espermatozoide/fisiologia , Animais , Axonema/metabolismo , Axonema/ultraestrutura , Dineínas/metabolismo , Infertilidade Masculina/etiologia , Masculino , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos , Motilidade Espermática/fisiologia , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/ultraestrutura
7.
PLoS One ; 15(4): e0232536, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353075

RESUMO

Sperm migration towards an oocyte in the female reproductive tract is an important step for successful fertilization. Although several sperm-chemotactic factors have been identified in mammals, it is unclear whether these chemoattractants contribute to sperm migration towards an oocyte that is the final destination for sperm. Furthermore, chemoattractants for bovine sperm are still undiscovered even though the follicular fluid attracts sperm in cattle. Here, we demonstrated that a single bovine cumulus-oocyte complex (COC) had the ability to attract sperm, suggesting that the COC secreted sperm chemoattractants. We identified stromal cell-derived factor 1 (SDF1), which was expressed in COCs, and its receptor CXCR4 in sperm, as a candidate. Our results showed that bovine sperm preferentially migrated to the area with a high SDF1 concentration and occasionally showed turn movements by asymmetric flagellar bends during the migration. We also demonstrated that increasing the intracellular Ca2+ concentration via Ca2+ channels was related to SDF1-induced sperm chemotaxis. Finally, a CXCR4 inhibitor significantly suppressed the in vitro bovine sperm migration towards a COC. Taken together, we propose that SDF1 is a chemotactic factor for bovine sperm to regulate their migration towards an oocyte via the CXCR4 receptor.


Assuntos
Quimiocina CXCL12/metabolismo , Quimiotaxia/fisiologia , Receptores CXCR4/metabolismo , Motilidade Espermática/fisiologia , Animais , Bovinos , Células do Cúmulo/metabolismo , Feminino , Fertilização In Vitro/veterinária , Microscopia Intravital , Masculino , Oócitos/metabolismo , Espermatozoides/fisiologia
8.
J Fish Biol ; 97(2): 435-443, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32415790

RESUMO

Sturgeon spermatozoa are unique for their sustained motility. We investigated the relative importance of bioenergetic pathways in the energy supply of Siberian sturgeon Acipenser baerii spermatozoa during motile and immotile states. Spermatozoon motility and oxygen consumption rate (OCR) were analysed following exposure to inhibitors of oxidative phosphorylation (sodium azide, NaN3 ), glycolysis (2-deoxy-D-glucose, DOG) and ß-oxidation of fatty acids (sodium fluoride, NaF), and to an uncoupler of oxidative phosphorylation (carbonyl cyanide m-chlorophenyl hydrazine, CCCP). No significant difference in curvilinear velocity was observed after addition of these reagents to activation medium (AM) or nonactivation medium (NAM) for incubation. Incubation of spermatozoa in NAM containing CCCP or NaN3 resulted in significantly decreased motility duration compared to controls. The OCR of sturgeon spermatozoa in AM (11.9 ± 1.4 nmol O2 min-1 (109 spz)-1 ) was significantly higher than in NAM (8.2 ± 1.5 nmol O2 min-1 (109 spz)-1 ). The OCR significantly declined with addition of NaN3 to AM and NAM. No significant difference in motility parameters or OCR was observed with NaF or DOG. These results suggest active oxidative phosphorylation in both immotile and motile spermatozoa. Nevertheless, mitochondrial respiration occurring during motility is not sufficient to meet the high energy demands, and the energy required for sustained motility of Siberian sturgeon spermatozoa is derived from adenosine triphosphate accumulated during the quiescent state.


Assuntos
Peixes/fisiologia , Motilidade Espermática/fisiologia , Espermatozoides/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Metabolismo Energético , Masculino , Mitocôndrias/metabolismo , Consumo de Oxigênio
9.
Trop Anim Health Prod ; 52(5): 2609-2619, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32451835

RESUMO

The study evaluated the effect of time of the year in which changes in photoperiod occurs on ostrich semen characteristics and male libido. Semen was collected for 5 days before, on and 5 days after winter solstice (21 June 2016), spring equinox (22 September 2016), summer solstice (21 December 2016) and autumn equinox (20 March 2017) in the southern hemisphere. Semen was collected from 10 South African Black ostrich males (average age ± standard deviation; 4.5 ± 2.27 years) using the dummy female. Semen volume, sperm concentration, total sperm per ejaculate, sperm motility traits, percentage of normal sperm, head and tail abnormalities and percentage of affected sperm in the hypo-osmotic swelling test (HOS) were evaluated. Male libido defined as the willingness of males to mount the dummy female was also recorded. Semen samples collected around summer solstice, spring and autumn equinox were higher in sperm concentration and sperm output compared with winter solstice (P < 0.05). Study periods did not influence semen volume, sperm motility traits, the percentage of normal sperm, head abnormalities and HOS. Tail abnormalities were higher around winter solstice than around spring equinox (P < 0.05). Male libido and the success of semen collection were significantly higher around spring equinox (P < 0.05). Changes in photoperiod in the southern hemisphere do not affect semen production in ostriches. However, high sperm output and male libido around spring equinox and summer solstice dates suggest that these periods may be preferred for semen collection for artificial insemination and storage purposes.


Assuntos
Análise do Sêmen/veterinária , Contagem de Espermatozoides/veterinária , Struthioniformes/fisiologia , Animais , Feminino , Masculino , Fotoperíodo , Estações do Ano , Sêmen , Comportamento Sexual Animal , Motilidade Espermática/fisiologia , Espermatozoides/fisiologia
10.
Georgian Med News ; (299): 26-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32242839

RESUMO

According to the statistics of the Russian Federation, the number of patients with male infertility increased by 60.3% over the past 12 years. Objective - to evaluate the activity of peripheral blood leukocytes, the rate of their production of reactive oxygen species, and the DNA fragmentation index in men with non-obstructive azoospermia. To solve this problem, we examined 65 men with non-obstructive idiopathic azoospermia. A control group consisted of 20 healthy fertile men. All patients underwent examination of ejaculate with measurement of levels of reactive oxygen species (ROS) and DNA fragmentation. To identify additional links in the pathogenesis of infertility, we determined the functional activity of peripheral blood leukocytes by registering luminol-dependent chemiluminescence (LCH) of leukocytes. The functional activity of leukocytes in men with azoospermia was found to be 4.5 times higher than in healthy men (p<0.01). We found that with such leukocyte activity the level of ROS and DNA fragmentation was 6 times higher in patients with infertility compared to the control group.


Assuntos
Azoospermia , Fragmentação do DNA , Infertilidade Masculina/etiologia , Leucócitos/fisiologia , Espermatozoides/metabolismo , Humanos , Masculino , Espécies Reativas de Oxigênio , Federação Russa , Motilidade Espermática/fisiologia
11.
Fertil Steril ; 113(4): 774-780.e3, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32228879

RESUMO

OBJECTIVE: To assess the timing of patency and late failure (secondary azoospermia) after vasovasostomy (VV) using standardized kinetics definitions. DESIGN: Retrospective cohort study. SETTING: University-affiliated hospital. PATIENT(S): Patients with obstructive azoospermia. INTERVENTION(S): Vasovasostomy. MAIN OUTCOME MEASURE(S): Univariate and multivariate logistic regression assessed predictors of patency and late failure. Patency was defined as any sperm return to the ejaculate; and >2 million total motile sperm (TMS) in ejaculate. Late failure after VV was defined as azoospermia; or <2 million TMS in ejaculate. RESULT(S): 429 men underwent VV, with median follow up of 242 days. Mean time to patency was 3.25 months versus 5.29 months in the "any sperm" versus ">2 million TMS" groups. Finding sperm intraoperatively during VV significantly improved patency rates in multivariable analysis (odds ratio [OR] 4.22). This association was further boosted when sperm was found bilaterally (OR 6.70). Late failure rate (azoospermia) was 10.6% at mean time of 14.1 months and 23% for <2 million, at mean time of 15.7 months. When assessing predictors of late failure, intraoperative motile sperm bilaterally was a statistically significant protective factor on multivariate analysis (hazard ratio 0.22). CONCLUSION(S): Vasovasostomy remains highly efficacious in treating obstructive azoospermia. Young patients, shorter obstructive intervals, and sperm identified intraoperatively predict improved outcomes. Clinicians can expect VV patency in 3 months and late failure within the first 2 years after surgery. However, patency rates, late failure rates, and kinetics vary by definition.


Assuntos
Azoospermia/diagnóstico , Ducto Deferente/cirurgia , Vasovasostomia/métodos , Adulto , Azoospermia/fisiopatologia , Estudos de Coortes , Seguimentos , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Motilidade Espermática/fisiologia , Resultado do Tratamento , Ducto Deferente/fisiopatologia , Vasovasostomia/tendências
12.
PLoS Comput Biol ; 16(3): e1007605, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32119665

RESUMO

Intracellular calcium ([Ca2+]i) is a basic and ubiquitous cellular signal controlling a wide variety of biological processes. A remarkable example is the steering of sea urchin spermatozoa towards the conspecific egg by a spatially and temporally orchestrated series of [Ca2+]i spikes. Although this process has been an experimental paradigm for reproduction and sperm chemotaxis studies, the composition and regulation of the signalling network underlying the cytosolic calcium fluctuations are hitherto not fully understood. Here, we used a differential equations model of the signalling network to assess which set of channels can explain the characteristic envelope and temporal organisation of the [Ca2+]i-spike trains. The signalling network comprises an initial membrane hyperpolarisation produced by an Upstream module triggered by the egg-released chemoattractant peptide, via receptor activation, cGMP synthesis and decay. Followed by downstream modules leading to intraflagellar pH (pHi), voltage and [Ca2+]i fluctuations. The Upstream module outputs were fitted to kinetic data on cGMP activity and early membrane potential changes measured in bulk cell populations. Two candidate modules featuring voltage-dependent Ca2+-channels link these outputs to the downstream dynamics and can independently explain the typical decaying envelope and the progressive spacing of the spikes. In the first module, [Ca2+]i-spike trains require the concerted action of a classical CaV-like channel and a potassium channel, BK (Slo1), whereas the second module relies on pHi-dependent CatSper dynamics articulated with voltage-dependent neutral sodium-proton exchanger (NHE). We analysed the dynamics of these two modules alone and in mixed scenarios. We show that the [Ca2+]i dynamics observed experimentally after sustained alkalinisation can be reproduced by a model featuring the CatSper and NHE module but not by those including the pH-independent CaV and BK module or proportionate mixed scenarios. We conclude in favour of the module containing CatSper and NHE and highlight experimentally testable predictions that would corroborate this conclusion.


Assuntos
Canais de Cálcio/metabolismo , Ouriços-do-Mar/metabolismo , Espermatozoides/fisiologia , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Quimiotaxia/fisiologia , Biologia Computacional/métodos , Íons/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Modelos Teóricos , Transdução de Sinais , Motilidade Espermática/fisiologia
13.
Sci Rep ; 10(1): 5625, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221341

RESUMO

Human sperm protein associated with the nucleus on the X chromosome (SPANX) genes encode a protein family (SPANX-A, -B, -C and -D), whose expression is limited to the testis and spermatozoa in normal tissues and to a wide variety of tumour cells. Present only in hominids, SPANX-A/D is exclusively expressed in post-meiotic spermatids and mature spermatozoa. However, the biological role of the protein family in human spermatozoa is largely unknown. Combining proteomics and molecular approaches, the present work describes the presence of all isoforms of SPANX-A/D in human spermatozoa and novel phosphorylation sites of this protein family. In addition, we identify 307 potential SPANX-A/D interactors related to nuclear envelop, chromatin organisation, metabolism and cilia movement. Specifically, SPANX-A/D interacts with fumarate hydratase and colocalises with both fumarate hydratase and Tektin 1 proteins, involved in meeting energy demands for sperm motility, and with nuclear pore complex nucleoporins. We provide insights into the molecular features of sperm physiology describing for the first time a multifunctional role of SPANX-A/D protein family in nuclear envelope, sperm movement and metabolism, considered key functions for human spermatozoa. SPANX-A/D family members, therefore, might be promising targets for sperm fertility management.


Assuntos
Proteínas Nucleares/metabolismo , Motilidade Espermática/fisiologia , Espermatozoides/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cromatina/genética , Células HEK293 , Células HeLa , Hominidae/metabolismo , Humanos , Masculino , Membrana Nuclear/metabolismo , Fosforilação/genética , Isoformas de Proteínas/metabolismo , Proteômica/métodos , Homologia de Sequência de Aminoácidos , Espermátides/metabolismo , Testículo/metabolismo , Fatores de Transcrição/metabolismo , Cromossomo X/genética
14.
Reprod Biol Endocrinol ; 18(1): 17, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32145746

RESUMO

Sperm cryopreservation has been widely used in assisted reproductive technology (ART) and has resulted in millions of live births. Two principal approaches have been adopted: conventional (slow) freezing and vitrification. As a traditional technique, slow freezing has been successfully employed and widely used at ART clinics whereas the latter, a process to solidify liquid into an amorphous or glassy state, may become a faster alternative method of sperm cryopreservation with significant benefits in regard to simple equipment and applicability to fertility centers. Sperm vitrification has its own limitations. Firstly, small volume of load is usually plunged to liquid nitrogen to achieve high cooling rate, which makes large volume sample cryopreservation less feasible. Secondly, direct contact with liquid nitrogen increases the potential risk of contamination. Recently, new carriers have been developed to facilitate improved control over the volume and speed, and new strategies have been implemented to minimize the contamination risk. In summary, although sperm vitrification has not yet been applied in routine sperm cryopreservation, its potential as a standard procedure is growing.


Assuntos
Criopreservação/métodos , Congelamento , Preservação do Sêmen/métodos , Espermatozoides/fisiologia , Vitrificação , Criopreservação/tendências , Humanos , Masculino , Reprodutibilidade dos Testes , Técnicas de Reprodução Assistida/tendências , Preservação do Sêmen/tendências , Motilidade Espermática/fisiologia
15.
Int J Mol Sci ; 21(5)2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32155986

RESUMO

Spermatozoa need to conduct a series of biochemical changes termed capacitation in order to fertilize. In vivo, capacitation is sequentially achieved during sperm transport and interaction with the female genital tract, by mechanisms yet undisclosed in detail. However, when boar spermatozoa are stored in the tubal reservoir pre-ovulation, most appear to be in a non-capacitated state. This study aimed at deciphering the transcriptomics of capacitation-related genes in the pig pre-ovulatory oviduct, following the entry of semen or of sperm-free seminal plasma (SP). Ex-vivo samples of the utero-tubal junction (UTJ) and isthmus were examined with a microarray chip (GeneChip® Porcine Gene 1.0 ST Array, Thermo Fisher Scientific) followed by bioinformatics for enriched analysis of functional categories (GO terms) and restrictive statistics. The results confirmed that entry of semen or of relative amounts of sperm-free SP modifies gene expression of these segments, pre-ovulation. It further shows that enriched genes are differentially associated with pathways relating to sperm motility, acrosome reaction, single fertilization, and the regulation of signal transduction GO terms. In particular, the pre-ovulation oviduct stimulates the Catsper channels for sperm Ca2+ influx, with AKAPs, CATSPERs, and CABYR genes being positive regulators while PKIs and CRISP1 genes appear to be inhibitors of the process. We postulate that the stimulation of PKIs and CRISP1 genes in the pre-ovulation sperm reservoir/adjacent isthmus, mediated by SP, act to prevent premature massive capacitation prior to ovulation.


Assuntos
Reação Acrossômica/fisiologia , Canais de Cálcio/metabolismo , Oviductos/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia , Animais , Cálcio/metabolismo , Canais de Cálcio/genética , Feminino , Fertilização/fisiologia , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ovulação/fisiologia , Inibidores de Proteínas Quinases/metabolismo , Sêmen/fisiologia , Transdução de Sinais/fisiologia , Motilidade Espermática/fisiologia , Suínos , Transcriptoma/fisiologia
16.
Anim Reprod Sci ; 215: 106329, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32216932

RESUMO

There are sperm subpopulations (SPs) with different kinematic characteristics in various species, however, biological relevance of these SPs is still uncertain. The objective of the present study was to investigate associations of motile sperm SPs with sperm characteristics determined by evaluations with flow cytometry and assessment of bull fertility, using multiple approaches for sperm clustering. Semen from 24 bulls was evaluated concomitantly using computer-assisted sperm analysis (CASA) and flow cytometry before freezing and after thawing. Motile SPs were determined utilizing two acknowledged clustering methods (TwoStep and K-Means) and one customized method. With the customized method, there was utilization of mean values of sperm velocity and linearity as thresholds for direct assignment of motile spermatozoa into four SPs. Regardless of approach for identifying SPs, sperm quality, as determined using flow cytometry, was correlated particularly with the subpopulation (SP) of fast and linear spermatozoa immediately after thawing and with the SP of fast and nonlinear spermatozoa before freezing and 3 h after thawing. Furthermore, there was a positive correlation between proportion of spermatozoa with fast and nonlinear movements before freezing and bull non-return to estrous rates. These results indicate that with different sperm SPs, there are different biological implications which can be evaluated to gain useful information concerning semen quality as determined using flow cytometry and fertility. Furthermore, determining SPs by assigning motile spermatozoa into clusters based on a combination of "below and "above" threshold values for sperm velocity and linearity might be considered a practical alternative to otherwise intricate clustering procedures.


Assuntos
Bovinos/fisiologia , Citometria de Fluxo , Análise do Sêmen/veterinária , Motilidade Espermática/fisiologia , Espermatozoides/classificação , Animais , Análise por Conglomerados , Fertilidade , Masculino , Espermatozoides/fisiologia
17.
Biomed Res Int ; 2020: 2934315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32047807

RESUMO

This study aimed to compare the quality of human spermatozoa vitrified by direct plunging into liquid nitrogen vs. liquid air. Spermatozoa were divided into three groups: fresh spermatozoa (Group F) were used as a control. Spermatozoa suspension (20 µl) was vitrified in open granules by direct dropping into liquid nitrogen (Group LN) or clean liquid air (Group LA). After warming at 37°C, the progressive motility rate of Group F was reduced from 65.9 ± 2.5% to 34.0 ± 1.9% (Group LN) and 38.1 ± 2.3% (Group LA), respectively (P1-2,3 < 0.05). The reductions in viability were 65.6 ± 2.2%, 29.0 ± 1.8%, and 36.6 ± 2.6% for Groups F, LN, and LA, respectively (P1-2,3 < 0.05). Comparing spermatozoa vitrified in liquid nitrogen vs. liquid air, no significant differences were detected in motility (34.0 ± 1.9% vs. 38.1 ± 2.3%), viability (29.0 ± 1.8% vs. 36.6 ± 2.6%), early apoptosis (13.8 ± 1.5% vs. 14.3 ± 1.8%), late apoptosis (45.5 ± 1.8% vs. 43.7 ± 2.2%), and necrosis (19.5 ± 2.0% vs. 15.0 ± 1.8%; p > 0.01 for all respective differences). There was a statistical tendency for increasing rates of "progressive motility" and "viability" and decreasing rates of "apoptosis" and "necrosis" when comparing spermatozoa vitrified in liquid air vs. liquid nitrogen. It is concluded that cryoprotectant-free vitrification by the direct dropping of human spermatozoa in a clean cooling agent (liquid air) is a good alternative to the use of nonsterile liquid nitrogen and can be used to cool cells while minimising the risk of microbial contamination.


Assuntos
Apoptose/fisiologia , Criopreservação/métodos , Preservação do Sêmen/métodos , Motilidade Espermática/fisiologia , Espermatozoides/fisiologia , Vitrificação , Ar , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Crioprotetores/efeitos adversos , Fertilidade/efeitos dos fármacos , Humanos , Masculino , Necrose/induzido quimicamente , Nitrogênio , Preservação do Sêmen/instrumentação , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
18.
Oxid Med Cell Longev ; 2020: 7038124, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089776

RESUMO

Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is a key structure influencing sperm morphology and function in normal and pathological conditions. The fatty acid profile determines the performance not only of sperm motility but also of acrosomal reaction and sperm-oocyte fusion. This review presents available knowledge on the role of fatty acid composition in human sperm and spermatogenesis and discusses the influence of dietary fatty acids on the sperm fatty acid profile. Recent studies in biological sciences and clinical researches in this field are also reported. The topic object of this review has potential application in medicine by identifying potential causes of infertility.


Assuntos
Ácidos Graxos/metabolismo , Infertilidade Masculina/fisiopatologia , Maturação do Esperma/fisiologia , Motilidade Espermática/fisiologia , Animais , Humanos , Masculino , Ratos
19.
Curr Opin Cell Biol ; 63: 154-161, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32097833

RESUMO

The mammalian flagellum is a specific type of motile cilium required for sperm motility and male fertility. Effective flagellar movement is dependent on axonemal function, which in turn relies on proper ion homeostasis within the flagellar compartment. This ion homeostasis is maintained by the concerted function of ion channels and transporters that initiate signal transduction pathways resulting in motility changes. Advances in electrophysiology and super-resolution microscopy have helped to identify and characterize new regulatory modalities of the mammalian flagellum. Here, we discuss what is currently known about the regulation of flagellar ion channels and transporters that maintain sodium, potassium, calcium, and proton homeostasis. Identification of new regulatory elements and their specific roles in sperm motility is imperative for improving diagnostics of male infertility.


Assuntos
Motilidade Espermática/fisiologia , Cauda do Espermatozoide/fisiologia , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Canais de Cálcio/fisiologia , Humanos , Masculino , Transdução de Sinais/fisiologia , Motilidade Espermática/genética , Cauda do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Espermatozoides/fisiologia
20.
Andrologia ; 52(3): e13523, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32017167

RESUMO

Spermatozoa are vulnerable to lack of energy and oxidative stress as a result of elevated levels of reactive oxygen species. Therefore, it is essential that appropriate nutrients are available during maturation. This randomised, double-blind, placebo-controlled trial investigated the effect of 6-month supplementation with carnitines and other micronutrients on sperm quality in 104 subjects with oligo- and/or astheno- and/or teratozoospermia with or without varicocele. Semen analyses were done at the beginning and end of the treatment. In addition to main analyses, post hoc analyses for age and body mass index (BMI) were carried out. Results were interpreted by dividing the population into two age and BMI classes. In 94 patients who completed the study, all sperm parameters increased in supplemented patients compared to the placebo group. A significant (p = .0272) difference in supplementation efficacy was observed for total motility on patients with varicocele and BMI < 25. In the same group, also the progressive motility was significantly superior (p = .0159). For Responder analysis, total motility results were confirmed in both the cited group (p = .0066) and in the varicocele group with BMI < 25 and age < 35 (p = .0078). This study suggests that supplementation is more effective in subjects with varicocele younger than 35 years with BMI < 25.


Assuntos
Antioxidantes/administração & dosagem , Índice de Massa Corporal , Suplementos Nutricionais , Infertilidade Masculina/dietoterapia , Micronutrientes/administração & dosagem , Varicocele/dietoterapia , Adolescente , Adulto , Fatores Etários , Método Duplo-Cego , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/patologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Placebos/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Contagem de Espermatozoides , Motilidade Espermática/efeitos dos fármacos , Motilidade Espermática/fisiologia , Resultado do Tratamento , Varicocele/complicações , Varicocele/patologia , Adulto Jovem
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