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1.
Ecotoxicol Environ Saf ; 208: 111694, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396025

RESUMO

Experimental studies have shown that nonradioactive strontium (Sr), in the form of Sr2+, have a positive effect on semen quality, but human evidence is lacking. This study aimed to examine the associations between nonradioactive Sr exposure and semen quality in Chinese men (n = 394). We recruited men who presented at an infertility clinic in Wuhan, China to seek for semen parameter analyses. Urinary Sr concentration as an exposure biomarker was measured using inductively coupled plasma mass spectrometer. We estimated the associations between urinary Sr concentrations and semen parameters using multivariable logistic and linear regression models. In multivariable linear regressions models, positive dose-response associations were estimated for sperm concentration, motility, and count across increasing urinary Sr quartiles (all p for trends<0.05), and the consistent positive associations were also observed for urinary Sr concentration modeled as a continuous exposure. In multivariable logistic models, decreased risks of below-reference sperm concentration, motility, and count were also estimated across increasing urinary Sr quartiles (all p for trends<0.05). Our results suggest that nonradioactive Sr exposure may have a beneficial effect on semen quality, but more investigations are warranted to confirm the results.


Assuntos
Exposição Ambiental/análise , Análise do Sêmen , Estrôncio/urina , Adulto , Biomarcadores/urina , China , Clínicas de Fertilização , Humanos , Masculino , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides/citologia
2.
PLoS One ; 15(12): e0230939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382704

RESUMO

The activation of C. elegans spermatids to crawling spermatozoa is affected by a number of genes including spe-47. Here, we investigate a paralog to spe-47: spe-50, which has a highly conserved sequence and expression, but which is not functionally redundant to spe-47. Phylogenetic analysis indicates that the duplication event that produced the paralogs occurred prior to the radiation of the Caenorhabditis species included in the analysis, allowing a long period for the paralogs to diverge in function. Furthermore, we observed that knockout mutations in both genes, either alone or together, have little effect on sperm function. However, hermaphrodites harboring both knockout mutations combined with a third mutation in the him-8 gene are nearly self-sterile due to a sperm defect, even though they have numerous apparently normal sperm within their spermathecae. We suggest that the sperm in these triple mutants are defective in fusing with oocytes, and that the effect of the him-8 mutation is unclear but likely due to its direct or indirect effect on local chromatin structure and function.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , Espermátides/metabolismo , Espermatozoides/metabolismo , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/classificação , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Sequência Conservada , Duplicação Gênica , Expressão Gênica , Técnicas de Inativação de Genes , Especiação Genética , Organismos Hermafroditas , Masculino , Mutação , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Contagem de Espermatozoides , Espermátides/citologia , Espermátides/crescimento & desenvolvimento , Espermatozoides/citologia , Espermatozoides/crescimento & desenvolvimento
3.
PLoS Biol ; 18(8): e3000838, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32804933

RESUMO

In humans, most germline mutations are inherited from the father. This observation has been widely interpreted as reflecting the replication errors that accrue during spermatogenesis. If so, the male bias in mutation should be substantially lower in a closely related species with similar rates of spermatogonial stem cell divisions but a shorter mean age of reproduction. To test this hypothesis, we resequenced two 3-4 generation nuclear families (totaling 29 individuals) of olive baboons (Papio anubis), who reproduce at approximately 10 years of age on average, and analyzed the data in parallel with three 3-generation human pedigrees (26 individuals). We estimated a mutation rate per generation in baboons of 0.57×10-8 per base pair, approximately half that of humans. Strikingly, however, the degree of male bias in germline mutations is approximately 4:1, similar to that of humans-indeed, a similar male bias is seen across mammals that reproduce months, years, or decades after birth. These results mirror the finding in humans that the male mutation bias is stable with parental ages and cast further doubt on the assumption that germline mutations track cell divisions. Our mutation rate estimates for baboons raise a further puzzle, suggesting a divergence time between apes and Old World monkeys of 65 million years, too old to be consistent with the fossil record; reconciling them now requires not only a slowdown of the mutation rate per generation in humans but also in baboons.


Assuntos
Mutação em Linhagem Germinativa , Hominidae/genética , Taxa de Mutação , Papio/genética , Reprodução/genética , Espermatozoides/metabolismo , Fatores Etários , Animais , Evolução Biológica , Divisão Celular , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Modelos Genéticos , Linhagem , Fatores Sexuais , Especificidade da Espécie , Espermatogênese/genética , Espermatozoides/citologia
4.
Nature ; 583(7815): 259-264, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32494014

RESUMO

Meiosis, although essential for reproduction, is also variable and error-prone: rates of chromosome crossover vary among gametes, between the sexes, and among humans of the same sex, and chromosome missegregation leads to abnormal chromosome numbers (aneuploidy)1-8. To study diverse meiotic outcomes and how they covary across chromosomes, gametes and humans, we developed Sperm-seq, a way of simultaneously analysing the genomes of thousands of individual sperm. Here we analyse the genomes of 31,228 human gametes from 20 sperm donors, identifying 813,122 crossovers and 787 aneuploid chromosomes. Sperm donors had aneuploidy rates ranging from 0.01 to 0.05 aneuploidies per gamete; crossovers partially protected chromosomes from nondisjunction at the meiosis I cell division. Some chromosomes and donors underwent more-frequent nondisjunction during meiosis I, and others showed more meiosis II segregation failures. Sperm genomes also manifested many genomic anomalies that could not be explained by simple nondisjunction. Diverse recombination phenotypes-from crossover rates to crossover location and separation, a measure of crossover interference-covaried strongly across individuals and cells. Our results can be incorporated with earlier observations into a unified model in which a core mechanism, the variable physical compaction of meiotic chromosomes, generates interindividual and cell-to-cell variation in diverse meiotic phenotypes.


Assuntos
Genoma Humano/genética , Meiose/genética , Espermatozoides/citologia , Espermatozoides/metabolismo , Adolescente , Adulto , Alelos , Aneuploidia , Troca Genética/genética , Haplótipos/genética , Humanos , Masculino , Não Disjunção Genética , Análise de Célula Única , Doadores de Tecidos , Adulto Jovem
5.
Sci Rep ; 10(1): 8862, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483250

RESUMO

Cell sorting via flow cytometry is a powerful tool to select subpopulations of cells in many biological fields. Selection of fertilisation-prone sperm is a critical step to ensure a stable and high fertilisation rate in in vitro fertilisation (IVF). However, a combination of conventional cell sorting and IVF system has not been established because of severe mechanical damages to the sperm during the sorting process. A cell sorter with microfluidics chip technology that lessens cell damage during cell sorting may address this problem. We evaluated the effects of microfluidics chip cell sorting on the sperm using the parameters, such as motility and fertility, and found this cell sorting method had minimal harmful effect on the sperm. Then, sperm were selected by a marker for acrosome reaction and showed higher fertilisation rate than that of the population of acrosome-intact sperm. Embryo derived from these sperm developed normally. These results indicated that microfluidics chip cell sorting can select fertile sperm to improve IVF technique.


Assuntos
Fertilidade/fisiologia , Citometria de Fluxo/métodos , Espermatozoides/fisiologia , Acrossomo/metabolismo , Animais , Feminino , Fertilização In Vitro , Dispositivos Lab-On-A-Chip , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Motilidade Espermática , Espermatozoides/citologia
6.
Proc Natl Acad Sci U S A ; 117(22): 12174-12181, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32409601

RESUMO

Germ cells have the ability to differentiate into eggs and sperm and must determine their sexual fate. In vertebrates, the mechanism of commitment to oogenesis following the sexual fate decision in germ cells remains unknown. Forkhead-box protein L3 (foxl3) is a switch gene involved in the germline sexual fate decision in the teleost fish medaka (Oryzias latipes). Here, we show that foxl3 organizes two independent pathways of oogenesis regulated by REC8 meiotic recombination protein a (rec8a), a cohesin component, and F-box protein (FBP) 47 (fbxo47), a subunit of E3 ubiquitin ligase. In mutants of either gene, germ cells failed to undergo oogenesis but developed normally into sperm in testes. Disruption of rec8a resulted in arrest at a meiotic pachytenelike stage specifically in females, revealing a sexual difference in meiotic progression. Analyses of fbxo47 mutants showed that this gene regulates transcription factors that facilitate folliculogenesis: LIM homeobox 8 (lhx8b), factor in the germline α (figla), and newborn ovary homeobox (nobox). Interestingly, we found that the fbxo47 pathway ensures that germ cells do not deviate from an oogenic pathway until they reach diplotene stage. The mutant phenotypes together with the timing of their expression imply that germline feminization is established during early meiotic prophase I.


Assuntos
Proteínas de Peixes/metabolismo , Células Germinativas/citologia , Gônadas/embriologia , Oogênese , Oryzias/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Proteínas de Peixes/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/fisiologia , Gônadas/metabolismo , Masculino , Meiose , Folículo Ovariano/citologia , Processos de Determinação Sexual , Espermatogênese , Espermatozoides/citologia
7.
J Dairy Sci ; 103(7): 6698-6705, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32359996

RESUMO

Quantifying the relative population of sperm cells bearing the X or Y chromosome in a sexed-semen sample has historically been limited to methods that are either low throughput and sensitive to user subjectivity (e.g., fluorescence in situ hybridization), conterminous (using the same technology to generate and confirm the sex skew), or relatively insensitive (including quantitative PCR with a change detection threshold of 2×). Customers pay a premium for sexed semen and should have access to reliable sex skew data, generated by an accurate, precise test that is orthogonal to the method used to generate sexed semen. Droplet digital PCR (ddPCR) has the capacity to provide an accurate and precise sex skew quantitation by subdividing a pool of template DNA into nanoliter-scale droplets containing either 1 or 0 copies of template DNA. Then PCR amplification is conducted in the droplets, and the number of copies of the amplicon of interest can be counted as the number of fluorescence-positive droplets based on classic quantitative PCR fluorescent reporters. We have optimized and validated a multiplexed ddPCR assay that uses this copy counting method to quantify the sex skew (ratio of X or Y chromosomes) in frozen-thawed bovine sexed semen. The assay interrogates at least 1,000 cells per sample well, quantifying X and Y chromosome copy numbers along with an autosomal gene, GAPDH, used as an internal assay control to confirm total cells counted. The ddPCR sex skew assay achieved a 0.5-percentage-point variance for %X or %Y with a broad linear detection range, from 10 to 95% X, and provided reproducible skew values across a range of 9 to 27 ng of genomic DNA input. This approach overcomes some limitations of other sex skew assays by quantifying absolute X and Y chromosome copy numbers, thus providing a rigorous, independent assessment of sex-skewed semen.


Assuntos
Bovinos/genética , Análise do Sêmen/veterinária , Análise para Determinação do Sexo/veterinária , Espermatozoides/citologia , Animais , DNA , Feminino , Hibridização in Situ Fluorescente/veterinária , Masculino , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Preservação do Sêmen , Cromossomo X , Cromossomo Y
8.
PLoS One ; 15(5): e0233885, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470029

RESUMO

In the Danio species, interspecific hybridization has been conducted in several combinations. Among them, only the hybrid between a zebrafish (D. rerio) female and a spotted danio (D. nigrofasciatus) male was reported to be fertile. However, beyond these investigations, by means of reproductive biology, gametes of the hybrid have also not been investigated genetically. For this study, we induced a hybrid of the D. rerio female and D. nigrofasciatus male in order to study its developmental capacity, reproductive performance and gametic characteristics. Its hybrid nature was genetically verified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the rhodopsin gene. Almost all the hybrids (36/37) were males, and only one was female. Developing oocytes were observed in the hybrid female, but ovulated eggs have not been obtained thus far. Microscopic observation revealed various head sizes of sperm in the hybrid males. Flow cytometry showed that the hybrid males generated aneuploid sperm with various ploidy levels up to diploidy. In backcrosses between D. rerio females and hybrid males, fertilization rates were significantly lower than the control D. rerio, and most resultant progeny with abnormal appearance exhibited various kinds of aneuploidies ranging from haploidy to triploidy, but only one viable progeny, which survived more than four months, was triploid. This suggested the contribution of fertile diploid sperm of the hybrid male to successful fertilization and development.


Assuntos
Aneuploidia , Fertilização/fisiologia , Hibridização Genética , Espermatozoides/fisiologia , Peixe-Zebra/genética , Peixe-Zebra/fisiologia , Animais , Cruzamentos Genéticos , DNA/genética , Feminino , Masculino , Ovário/citologia , Ploidias , Rodopsina/genética , Razão de Masculinidade , Espermatozoides/citologia
9.
Am J Clin Nutr ; 112(3): 707-719, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32453396

RESUMO

BACKGROUND: It is unknown which compounds in spermatozoa or seminal plasma may be involved in the regulation of sperm motility. OBJECTIVES: The aim of this study was to investigate the effects of DHA (22:6n-3), vitamin E, and their probable interactions in men with asthenozoospermia. METHODS: A factorial, randomized, double-blind, placebo-controlled trial was conducted in infertility clinics in Tehran, Iran. The participants were idiopathic asthenozoospermic men aged 20-45 y, with normal endocrine function. Their concentration of spermatozoa and percentage of morphologically normal spermatozoa were equal to or above the lower reference limits, according to the fifth edition of the WHO guideline. Out of 717 men referred to the infertility clinics, 180 asthenozoospermic men were randomly assigned to 1 of 4 groups according to stratified blocked randomization by age and sperm concentration. Participants took daily 465 mg DHA plus 600 IU vitamin E (DE), 465 mg DHA plus placebo (DP), 600 IU vitamin E plus placebo (EP), or both placebo capsules (PP) for 12 wk. Sperm characteristics, oxidative stress of seminal plasma, serum and sperm membrane fatty acids, dietary intakes, anthropometric measurements, and physical activity were measured at baseline and after 12 wk. RESULTS: After the intervention, mean ± SD sperm progressive motility was greater in the DE group (27.9 ± 2.8) than in the DP (25.7 ± 3.4), EP (26.1 ± 2.8), and PP (25.8 ± 2.6) groups (P < 0.05). Sperm count (P = 0.001) and concentration (P = 0.044) increased significantly in the DE group compared with the other 3 groups, whereas other semen parameters were not significantly different between the groups after the intervention. Serum concentrations of n-3 PUFAs were significantly higher in the DE and DP groups than in the EP and PP groups. CONCLUSIONS: Combined DHA and vitamin E supplements led to increased sperm motility; however, no significant changes occurred in sperm morphology and vitality in asthenozoospermic men.This trial was registered at clinicaltrials.gov as NCT01846325.


Assuntos
Astenozoospermia/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/administração & dosagem , Infertilidade Masculina/tratamento farmacológico , Fosfolipídeos/metabolismo , Sêmen/metabolismo , Espermatozoides/citologia , Vitamina E/administração & dosagem , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/fisiopatologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Fosfolipídeos/química , Sêmen/química , Sêmen/efeitos dos fármacos , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Adulto Jovem
10.
J Appl Microbiol ; 129(3): 521-531, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32281210

RESUMO

AIM: To evaluate the bacterial composition of collared peccary semen and foreskin mucosa, and to verify the sensitivity of isolates to antimicrobials used in semen conservation and to Aloe vera gel, which is an alternative external cryoprotectant. METHODS AND RESULTS: Nine foreskin mucosa and ejaculate samples from adult animals were used. Sperm characteristics and bacterial load were evaluated in fresh semen. The preputial mucosa and semen bacterial isolates were identified and tested against five concentrations of each antimicrobial (streptomycin-penicillin and gentamicin) and A. vera gel. Corynebacterium sp. and Staphylococcus sp. were isolated in greater numbers than others in both semen (64·10 and 20·51%, respectively) and the foreskin mucosa (60·60 and 24·25%, respectively), and ranged from 0·4 to 21 × 105 colony-forming units (CFU) per ml. The average load of Corynebacterium sp. was negatively correlated (P < 0·05) with the sperm membrane integrity (r = -0·73055) and curvilinear velocity (r = -0·69048). Streptomycin-penicillin and gentamicin inhibited most micro-organisms, and A. vera showed lower antimicrobial activity. CONCLUSION: Several Gram-positive bacteria are present in semen and foreskin mucosa of collared peccary, and the benefits of using primarily penicillin-streptomycin and gentamicin antimicrobials in the bacterial control of diluted semen of these animals are strongly indicated. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides insight into the reproductive microbiota of captive male-collared peccary. This work provides a theoretical basis to assist reproductive biotechnologies for ex situ conservation of the species.


Assuntos
Artiodáctilos/microbiologia , Prepúcio do Pênis/microbiologia , Microbiota , Sêmen/microbiologia , Espermatozoides/fisiologia , Aloe , Animais , Antibacterianos/farmacologia , Artiodáctilos/fisiologia , Bactérias Aeróbias/classificação , Bactérias Aeróbias/efeitos dos fármacos , Bactérias Aeróbias/isolamento & purificação , Crioprotetores/farmacologia , Masculino , Membrana Mucosa/microbiologia , Espermatozoides/citologia
11.
Sci Rep ; 10(1): 6430, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286479

RESUMO

Aiming to investigate trends in seminal parameter values among Brazilian men between 1995 and 2018, we performed a retrospective analysis of spermograms of couples admitted for infertility testing at UNICAMP/Brazil. For the present study, only the first sample produced by each man was analyzed (9,267 samples). Total motile sperm count (TMSC), percentage of spermatozoa with normal morphology (NM), and sperm concentration after seminal processing (SCA) were considered dependent variables. Statistical analysis was carried out through linear regression for the median values both in the general population and in the population categorized by age group (<30, 30-39, and ≥40 years). During the study period, the mean age of men was 32.46 (± 6.48) years, with a median of 32 (18-67) years. We found a significant decrease in the median values of TMSC (reduction of 2.84 million/year), NM (reduction of 0.52% each year) and SCA (reduction of 0.24 million/mL each year). In conclusion, we observed that Brazilian men undergoing infertility investigation had a decline in seminal parameters in the past 23 years. Surveillance should be maintained in the coming years, and further studies are needed to elucidate possible causes for seminal deterioration and to devise strategies to reverse this trend.


Assuntos
Sêmen/metabolismo , Adulto , Brasil , Humanos , Modelos Lineares , Masculino , Manejo de Espécimes , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides/citologia
12.
Top Companion Anim Med ; 38: 100372, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32115080

RESUMO

Some studies have demonstrated that glycerol is superior to amides in preserving sperm motion characteristics of canine sperm; however, little is known about the effect of these cryoprotectants on the membrane characteristics of canine spermatozoa after freezing/thawing. In this study, the effects of using either N-N-dimethylformamide (DMF) or glycerol (GLY) on the integrity and function of the canine sperm, after cryopreservation were determined. We hypothesized that the use of a multiparametric approach for assessing the effect of DMF on the membranes of canine sperm would explain the lower values reported for post-thaw motility. Ejaculates from 12 dogs were collected, split into 2 groups, and frozen using a tris-fructose-citrate-egg yolk-based extender containing either 7% (v/v) GLY or 7% (v/v) DMF. Frozen straws (n = 120) were thawed and analyzed for subjectively-assessed sperm progressive motility, normal morphology, plasma membrane integrity, plasma membrane function (HOST+), acrosome membrane integrity, high mitochondrial membrane potential, and simultaneous assessment of sperm membrane integrity and function by a triple-staining fluorescent procedure. Overall, sperm motility and membrane intactness/function were higher when GLY was used as a cryoprotectant, as compared to DMF (P < .05). A model to explain the variation in progressive motility using the values obtained from the sperm integrity and function parameters was designed. The percent HOST+ sperm and high mitochondrial membrane potential sperm were mostly associated with the changes observed in the progressive motility (r2 = 0.84; P = .043) when either GLY or DMF were used as cryoprotectants. These results may explain the overall reduced sperm quality observed after cryopreservation, as a reflection of sublethal damage sustained by the sperm membranes.


Assuntos
Crioprotetores/farmacologia , Dimetilformamida/farmacologia , Cães/fisiologia , Glicerol/farmacologia , Espermatozoides/efeitos dos fármacos , Animais , Criopreservação/métodos , Criopreservação/veterinária , Congelamento , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/citologia
13.
Int J Mol Sci ; 21(6)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197481

RESUMO

Nitric oxide (NO·), synthesized from L-arginine by nitric oxide synthase (NOS), is involved in sperm functionality. NOS isoforms have been detected in spermatozoa from different species, and an increment in NOS activity during capacitation has been reported. This work aims to determine the presence and localization of NOS isoforms in ram spermatozoa and analyse their possible changes during in vitro capacitation. Likewise, we investigated the effect of melatonin on the expression and localization of NOS and NO· levels in capacitated ram spermatozoa. Western blot analysis revealed protein bands associated with neuronal NOS (nNOS) and epithelial NOS (eNOS) but not with inducible NOS (iNOS). However, the three isoforms were detected by indirect immunofluorescence (IFI), and their immunotypes varied over in vitro capacitation with cAMP-elevating agents. NO· levels (evaluated by DAF-2-DA/PI staining) increased after in vitro capacitation, and the presence of L-arginine in the capacitating medium raised NO· production and enhanced the acrosome reaction. Incubation in capacitating conditions with a high-cAMP medium with melatonin modified the NOS distribution evaluated by IFI, but no differences in Western blotting were observed. Melatonin did not alter NO· levels in capacitating conditions, so we could infer that its role in ram sperm capacitation would not be mediated through NO· metabolism.


Assuntos
Melatonina/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Capacitação Espermática/efeitos dos fármacos , Espermatozoides/enzimologia , Animais , Masculino , Ovinos , Espermatozoides/citologia
14.
PLoS Biol ; 18(3): e3000663, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32203540

RESUMO

During in vitro fertilisation (IVF), pharmacological activation of the murine X chromosome-encoded receptor proteins Toll-like receptor (TLR) 7 and TLR8 reportedly results in male-biased litters by selectively disrupting the motility of X-bearing sperm cells. Thus-in the context of agonist treatment during IVF-these receptors act as 'suicidal' segregation distorters that impair their own transmission to the next generation. Such behaviour would, from an evolutionary perspective, be strongly selected against if present during natural fertilisation. Consequently, TLR7/8 biology in vivo must differ significantly from this in vitro situation to allow these genes to persist in the genome. Here, we use our current understanding of male germ cell biology and TLR function as a starting point to explore the mechanistic and evolutionary aspects of this apparent paradox.


Assuntos
Espermatozoides/fisiologia , Receptores Toll-Like/metabolismo , Cromossomo X , Animais , Evolução Biológica , Humanos , Masculino , Transporte de RNA , Razão de Masculinidade , Espermatogênese , Espermatozoides/citologia , Espermatozoides/metabolismo , Receptores Toll-Like/genética
15.
Adv Clin Chem ; 95: 149-163, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32122522

RESUMO

Exosomes are nanosized membrane vesicles secreted by wide variety of cells and found in abundance in biological fluids including semen. They contain cargo of lipids, proteins, microRNAs and mRNAs, and are known to play a major role in intracellular communication. Seminal exosomes mainly include epididymosomes and prostasomes. Most of the proteins associated with the epididymosomes are transferred to the sperm subcellular or membranous domains during their epididymal transit and are involved in the acquisition of fertilizing ability, modulation of motility and protection against oxidative stress. Proteins associated with prostasomes stimulate sperm motility and regulate the timing of capacitation to avoid premature induction of acrosome reaction. Furthermore, prostasomes protect the sperm from immune responses within the female reproductive tract. Overall, exosome-associated proteins play an indispensable role in maturation of spermatozoa and therefore, serve as an excellent biomarker in early diagnosis of male infertility.


Assuntos
Epididimo/metabolismo , Exossomos/metabolismo , Fertilidade/fisiologia , Animais , Epididimo/citologia , Epididimo/patologia , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Espermatozoides/citologia , Espermatozoides/metabolismo
16.
Anim Sci J ; 91(1): e13328, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32219925

RESUMO

This study was aimed to investigate whether and how Rutin protects boar sperm against cryoinjury during cryopreservation. Five concentrations of Rutin with 0.2, 0.4, 0.6, 1.0, and 2.0 mM were added to the freezing extender of boar sperm, respectively, and the effects on quality and function of boar sperm after freezing-thawing were assessed. The results showed that the sperm motility, mitochondrial activity, plasma membrane integrity, and acrosomal integrity were significantly improved in 0.4 mM and 0.6 mM Rutin groups (p < .05). Compared with ganoderma lucidum polysaccharide (GLP) or Tanshinone IIA, Rutin exhibited higher rates of mitochondrial activity and acrosome integrity (p < .05). Mechanistically, the addition of Rutin at the concentration of 0.6, 0.8, and 1.0 mM significantly attenuated ROS accumulation and MDA production by improving antioxidant enzymatic activity, including SOD, CAT, and GSH-Px (p < .05). Functionally, a higher penetration rate and the increased total efficiency of fertilization were observed in the 0.4, 0.6, and 1.0 mM Rutin groups than in the control group (p < .05). Moreover, the addition of Rutin (0.6 mM) significantly induced an increase in both the cleavage and blastocyst rates (p < .05). In summary, supplementation with Rutin in cryopreservation medium protects boar sperm against ROS attack by enhancing the antioxidative defense.


Assuntos
Antioxidantes/uso terapêutico , Criopreservação , Congelamento/efeitos adversos , Rutina/farmacologia , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/patologia , Acrossomo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Membrana Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/citologia , Espermatozoides/metabolismo , Superóxido Dismutase/metabolismo , Suínos
17.
Sci Rep ; 10(1): 3888, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127590

RESUMO

Adult stem cells divide to renew the stem cell pool and replenish specialized cells that are lost due to death or usage. However, little is known about the mechanisms regulating how stem cells adjust to a demand for specialized cells. A failure of the stem cells to respond to this demand can have serious consequences, such as tissue loss, or prolonged recovery post injury. Here, we challenge the male germline stem cells (GSCs) of Drosophila melanogaster for the production of specialized cells, sperm cells, using mating experiments. We show that repeated mating reduced the sperm pool and increased the percentage of GSCs in M- and S-phase of the cell cycle. The increase in dividing GSCs depended on the activity of the highly conserved G-proteins. Germline expression of RNA-Interference (RNA-i) constructs against G-proteins, or a dominant negative G-protein eliminated the increase in GSC division frequency in mated males. Consistent with a role for the G-proteins in regulating GSC division frequency, RNA-i against seven out of 35 G-protein coupled receptors (GPCRs) within the germline cells also eliminated the capability of males to increase the numbers of dividing GSCs in response to mating.


Assuntos
Divisão Celular , Drosophila melanogaster , Proteínas de Ligação ao GTP/metabolismo , Transdução de Sinais , Espermatozoides/citologia , Células-Tronco/citologia , Animais , Masculino , Fase S , Comportamento Sexual Animal
18.
Andrologia ; 52(3): e13539, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32030798

RESUMO

Asthenozoospermia (AZS), which characterised by reduced forward sperm motility, is a common cause of male infertility. Recently, mitochondrial dysfunction reported in AZS men came to attention for finding the molecular aetiology of AZS. Mitochondria-related microRNAs (miRNAs) are the most important regulators of mitochondrial function through post-transcriptionally modulation of gene expression. Therefore, this study aims to evaluate the expression of four recently reported mitochondrial-related miRNAs (miR-4485-3p/4484/4461 and 4463) in the sperm sample of asthenozoospermic men. RNA was extracted from spermatozoa of 74 volunteers (39 patients with idiopathic AZS and 35 controls with normal fertility), and relative gene expression analysis was performed by quantitative PCR. We used SNORD48 as a normaliser gene, and quantification was calculated by 2-ΔΔCt method. The expression of miR-4484 and miR-4461 was not detected in the spermatozoa of cases and controls. However, miR-4485-3p (p = .006) was significantly downregulated in the AZS men compared with the controls, but the miR-4463 expression was not significantly different between the two groups (p = .5). Bioinformatic analysis identified three target genes for miR-4485-3p (DNAH1, KIT and PARK7) that are related to male infertility. In conclusion, the downregulation of miR-4485-3p was associated with idiopathic AZS, which could be a molecular link between mitochondrial dysfunction and AZS.


Assuntos
Astenozoospermia/genética , MicroRNAs/metabolismo , RNA Mitocondrial/metabolismo , Espermatozoides/metabolismo , Adulto , Astenozoospermia/patologia , Estudos de Casos e Controles , Biologia Computacional , Regulação para Baixo , Dineínas/genética , Humanos , Masculino , MicroRNAs/isolamento & purificação , Mitocôndrias/metabolismo , Proteína Desglicase DJ-1/genética , Proteínas Proto-Oncogênicas c-kit/genética , Reação em Cadeia da Polimerase em Tempo Real , Motilidade Espermática/genética , Espermatozoides/citologia , Espermatozoides/patologia
19.
Sci Rep ; 10(1): 2235, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32042017

RESUMO

Supplemental energy and protein during calf-hood (2-30 wk) in dairy bulls hastened puberty (~1 mo), upregulated steroid biosynthesis, concentrations of reproductive hormones and Sertoli cell maturation, with larger testes and greater sperm production (~25%) in mature bulls. The objective was to evaluate effects of feeding high (20.0% crude protein [CP], 67.9% total digestible nutrients [TDN]), control/medium (17.0% CP, 66.0% TDN) and low (12.2% CP, 62.9% TDN) diets from 2 to 30 wk on post-pubertal testes of Holstein bulls. Based on RNA sequencing, 497 and 2961 genes were differentially expressed (P < 0.1) in high- vs low- and high- vs medium-diet groups, respectively. According to KEGG analysis, oxidative phosphorylation and ribosome pathways were upregulated in high- vs medium- and low-diet groups, with majority of upregulated genes encoding for essential subunits of complex I, III, IV and V of OXYPHOS pathway. In addition, mitochondrial translation, mitotic nuclear division and cell division were enriched in high- vs medium-diet groups. Consistent with these results, a greater percentage of sperm from high-diet bulls were progressively motile and had normal mitochondrial function compared to medium-diet sperm (P < 0.1). Thus, enhanced early life nutrition upregulated mitochondrial function in testes and sperm of post-pubertal Holstein bulls.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Suplementos Nutricionais , Mitocôndrias/metabolismo , Maturidade Sexual , Espermatozoides/metabolismo , Testículo/metabolismo , Ração Animal/análise , Animais , Bovinos , Masculino , Estado Nutricional , Proteínas/metabolismo , Sêmen/metabolismo , Espermatozoides/citologia
20.
Int J Mol Sci ; 21(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054116

RESUMO

Excessive levels of reactive nitrogen species (RNS) produce nitrosative stress. Among RNS is peroxynitrite, a highly reactive free radical generated when nitric oxide reacts with superoxide anion. Peroxynitrite effects have been mainly studied in somatic cells, and in spermatozoa the majority of studies are focused in humans. The aim of this study is to investigate the in vitro peroxynitrite effect on boar spermatozoa functions and the molecular mechanisms involved. Spermatozoa were exposed to the donor 3-morpholinosydnonimine (SIN-1) in non-capacitating or capacitating medium, motility was evaluated by CASA, functional parameters by flow cytometry and sperm protein phosphorylation by Western blotting. SIN-1 treatment, that significantly increases peroxynitrite levels in boar spermatozoa, potentiates the capacitating-stimulated phosphorylation of cAMP-dependent protein kinase 1 (PKA) substrates and GSK-3α. SIN-1 induced peroxynitrite does not decrease sperm viability, but significantly reduces sperm motility, progressive motility, velocities and motility coefficients. Concomitantly, peroxynitrite does not affect mitochondrial membrane potential, plasma membrane fluidity, or A23187-induced acrosome reaction. However, peroxynitrite significantly increases sperm lipid peroxidation in both media. In conclusion, peroxynitrite compromises boar sperm motility without affecting mitochondrial activity. Although peroxynitrite potentiates the phosphorylation of pathways leading to sperm motility, it also causes oxidative stress that might explain, at least partially, the motility impairment.


Assuntos
Estresse Nitrosativo , Ácido Peroxinitroso/metabolismo , Motilidade Espermática , Espermatozoides/citologia , Sus scrofa/metabolismo , Animais , Sobrevivência Celular , Peroxidação de Lipídeos , Masculino , Potencial da Membrana Mitocondrial , Análise do Sêmen , Espermatozoides/metabolismo
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