Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59.664
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
Braz. j. biol ; 83: e245329, 2023. graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1285618

RESUMO

Abstract The cold storage of milt implies potentials alterations in its quality because the storage generates as main process, free radicals that produce spermatozoa membrane lipids damage with the consequent motility and fertilising capacity disruptions. To decrease the damage generated by free radicals the cells have antioxidant defences (proteins, enzymes, and low molecular weight substances). The objective of the present study evaluated the time storage effect and different antioxidants prepared in spermatic diluents on sperm viability of O. mykiss milt stored at 4°C. The two-way ANOVA denoted that the time storage and antioxidant influence have significant effects separated or combined on viability parameters (sperm motility and viability, proteins concentrations and superoxide dismutase enzymatic activity in seminal plasma). In contrast, only the storage time affected the fertilising capacity and catalase enzymatic activity in seminal plasma. The resulting analysis can conclude that the antioxidant presence improves the viability of cold stored milt, especially the transport conditions and the antioxidants allow the fecundity despite motility decrease.


Resumo O armazenamento a frio de leite implica potenciais alterações em sua qualidade, pois gera como processo principal radicais livres que provocam danos aos lipídios da membrana dos espermatozoides, com as consequentes alterações na motilidade e na capacidade de fertilização. Para diminuir os danos causados pelos radicais livres, as células têm defesas antioxidantes (proteínas, enzimas e substâncias de baixo peso molecular). O presente estudo avaliou o efeito do tempo de armazenamento e diferentes antioxidantes preparados em diluentes espermáticos no armazenamento de viabilidade de O. mykiss milt a 4°C. A ANOVA de duas vias denotou que o armazenamento no tempo e a influência antioxidante têm efeitos significativos separados ou combinados nos parâmetros de viabilidade (motilidade espermática, viabilidade espermática, concentrações de proteínas e atividade enzimática da superóxido dismutase no plasma seminal), enquanto apenas o tempo de armazenamento afetou a capacidade de fertilização e atividade enzimática da catalase no plasma seminal. A análise resultante pode concluir que a presença de antioxidante melhora a viabilidade do leite frio, especialmente as condições de transporte, e os antioxidantes permitem a fecundidade apesar da diminuição da motilidade.


Assuntos
Animais , Masculino , Preservação do Sêmen/veterinária , Oncorhynchus mykiss , Motilidade Espermática , Espermatozoides , Criopreservação , Antioxidantes
2.
Mol Hum Reprod ; 28(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34954800

RESUMO

Sperm DNA damage is considered a predictive factor for the clinical outcomes of patients undergoing ART. Laboratory evidence suggests that zygotes and developing embryos have adopted specific response and repair mechanisms to repair DNA damage of paternal origin. We have conducted a systematic review in accordance with guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) to identify and review the maternal mechanisms used to respond and repair sperm DNA damage during early embryonic development, how these mechanisms operate and their potential clinical implications. The literature search was conducted in Ovid MEDLINE and Embase databases until May 2021. Out of 6297 articles initially identified, 36 studies were found to be relevant through cross referencing and were fully extracted. The collective evidence in human and animal models indicate that the early embryo has the capacity to repair DNA damage within sperm by activating maternally driven mechanisms throughout embryonic development. However, this capacity is limited and likely declines with age. The link between age and decreased DNA repair capacity could explain decreased oocyte quality in older women, poor reproductive outcomes in idiopathic cases and patients who present high sperm DNA damage. Ultimately, further understanding mechanisms underlying the maternal repair of sperm DNA damage could lead to the development of targeted therapies to decrease sperm DNA damage, improved oocyte quality to combat incoming DNA insults or lead to development of methodologies to identify individual spermatozoa without DNA damage.


Assuntos
Dano ao DNA , Reparo do DNA , Idoso , Animais , Dano ao DNA/genética , Reparo do DNA/genética , Desenvolvimento Embrionário/genética , Feminino , Humanos , Masculino , Oócitos/fisiologia , Gravidez , Espermatozoides/fisiologia
3.
Sci Rep ; 12(1): 7407, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523907

RESUMO

The assessment of the impact of chemotherapies on in vitro spermatogenesis in experimental models is required before considering the application of this fertility restoration strategy to prepubertal boys who received these treatments before testicular tissue cryopreservation. The present work investigated the effects of exposure of prepubertal mice to mono- (vincristine or cyclophosphamide) and polychemotherapy (a combination of vincristine and cyclophosphamide) on the first wave of in vitro spermatogenesis. When testicular tissue exposed to monochemotherapy was preserved, polychemotherapy led to severe alterations of the seminiferous epithelium and increased apoptosis in prepubertal testes prior in vitro maturation, suggesting a potential additive gonadotoxic effect. These alterations were also found in the testicular tissues of polychemotherapy-treated mice after 30 days of organotypic culture and were associated with a reduction in the germ cell/Sertoli cell ratio. The different treatments neither altered the ability of spermatogonia to differentiate in vitro into spermatozoa nor the yield of in vitro spermatogenesis. However, more spermatozoa with morphological abnormalities and fragmented DNA were produced after administration of polychemotherapy. This work therefore shows for the first time the possibility to achieve a complete in vitro spermatogenesis after an in vivo exposure of mice to a mono- or polychemotherapy before meiotic entry.


Assuntos
Espermatogênese , Espermatogônias , Animais , Ciclofosfamida/efeitos adversos , Quimioterapia Combinada , Humanos , Masculino , Camundongos , Espermatogênese/genética , Espermatozoides , Testículo , Vincristina
4.
BMC Genomics ; 23(1): 344, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508966

RESUMO

BACKGROUND: The gaur (Bos gaurus) is the largest extant wild bovine species, native to South and Southeast Asia, with unique traits, and is listed as vulnerable by the International Union for Conservation of Nature (IUCN). RESULTS: We report the first gaur reference genome and identify three biological pathways including lysozyme activity, proton transmembrane transporter activity, and oxygen transport with significant changes in gene copy number in gaur compared to other mammals. These may reflect adaptation to challenges related to climate and nutrition. Comparative analyses with domesticated indicine (Bos indicus) and taurine (Bos taurus) cattle revealed genomic signatures of artificial selection, including the expansion of sperm odorant receptor genes in domesticated cattle, which may have important implications for understanding selection for male fertility. CONCLUSIONS: Apart from aiding dissection of economically important traits, the gaur genome will also provide the foundation to conserve the species.


Assuntos
Receptores Odorantes , Animais , Bovinos/genética , Genoma , Genômica , Masculino , Mamíferos , Receptores Odorantes/genética , Espermatozoides , Glicoproteínas da Zona Pelúcida
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(1): 63-71, 2022 Jan 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-35545364

RESUMO

OBJECTIVES: As a remedy for the failure of in vitro fertilization (IVF), rescue intracytoplasmic sperm injection (R-ICSI) has been widely carried out, but it has failed to significantly improve the fertilization rate and clinical pregnancy rate. Sperm DNA fragmentation index (DFI) was highly correlated with pregnancy outcome of artificial assisted reproduction. This study aims to investigate the effect of the sperm DFI on the outcome of R-ICSI and the clinical value of R-ICSI. METHODS: This retrospective analysis was conducted among 140 infertile couples receiving R-ICSI in from January 2014 to December 2019. The subjects were assigned into a total fertilization failure (TFF)+low DFI group (R-ICSI after TFF and DFI<30%) (n=63), a TFF+high DFI group (R-ICSI after TFF and DFI≥30%) (n=16), a partial fertilization failure (PFF)+low DFI group (R-ICSI after PFF and DFI<30%) (n=52), a PFF+high DFI group (R-ICSI after PFF and DFI≥30%) (n=9). All transferred embryos were come from R-ICSI. The general clinical data [infertility duration, male age, female age, basal serum level of follicle stimulating hormone (FSH), basal serum level of luteinizing hormone (LH), antral follicle count, endometrial thickness of human chorionic gonadotropin (HCG) day, and eggs] and R-ICSI cycle outcomes (fertilization rate, normal fertilization rate, cleavage rate, good embryo rate, implantation rate, clinical pregnancy rate and live birth rate) were analyzed. In addition, the effect of R-ICSI on the fertilization outcome of conventional IVF total fertilization failure and partial fertilization failure was explored. RESULTS: There was no significant difference in the general clinical data and R-ICSI cycle outcome between the TFF+low DFI group and the TFF+high DFI group (all P>0.05). There was no significant difference in the general clinical data between the PFF+low DFI group and the PFF+high DFI group (all P>0.05). The fertilization rate and normal fertilization rate in the PFF+low DFI group were significantly higher than those in the PFF+high DFI group (85.40% vs 72.41%, 71.90% vs 58.62%, respectively; both P<0.05). However, there was no significant difference in cleavage rate, good embryo rate, implantation rate, clinical pregnancy rate, and live birth rate between the 2 groups (all P>0.05). The R-ICSI cycle of TFF: A total of 79 fresh cycles, 57 fresh transplant cycles, a total of 761 unfertilized oocytes, and 584 M II oocytes were treated with R-ICSI, the fertilization rate was 83.22%, the normal fertilization rate was 75.51%, the cleavage rate was 98.15%, the good embryo rate was 40.74%, the implantation rate was 30.56%, and the clinical pregnancy rate was 43.86%; 29 live births were obtained. The R-ICSI cycle of PFF: A total of 61 fresh cycles, 31 fresh transplant cycles, a total of 721 unfertilized oocytes, and 546 M II oocytes were treated with R-ICSI; the fertilization rate was 83.33%, the normal fertilization rate was 69.78%, the cleavage rate was 97.36%, the good embryo rate was 44.39%, the implantation rate was 25.42%, and the clinical pregnancy rate was 45.16%; 12 live births were obtained. CONCLUSIONS: In the case of partial fertilization failure of IVF, the sperm DFI affects the fertilization rate and normal fertilization rate of R-ICSI; whether it is a TFF of IVF or PFF of IVF, ICSI can be used as an effective remedy way.


Assuntos
Fertilização In Vitro , Injeções de Esperma Intracitoplásmicas , Fragmentação do DNA , Feminino , Humanos , Masculino , Gravidez , Estudos Retrospectivos , Espermatozoides
6.
Sci Rep ; 12(1): 8554, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595785

RESUMO

Mammalian sex chromosomes are enriched for large, nearly-identical, palindromic sequences harboring genes expressed predominately in testicular germ cells. Discerning if individual palindrome-associated gene families are essential for male reproduction is difficult due to challenges in disrupting all copies of a gene family. Here we generate precise, independent, deletions to assess the reproductive roles of two X-linked palindromic gene families with spermatid-predominant expression, 4930567H17Rik and Mageb5. Sequence analyses reveals mouse 4930567H17Rik and Mageb5 are orthologs of human HSFX3 and MAGEB5, respectively, where 4930567H17Rik/HSFX3 is harbored in a palindrome in humans and mice, while Mageb5 is not. Additional sequence analyses show 4930567H17Rik and HSFX3 are rapidly diverging in rodents and primates, respectively. Mice lacking either 4930567H17Rik or Mageb5 gene families do not have detectable defects in male fertility, fecundity, spermatogenesis, or in gene regulation, but do show differences in sperm head morphology, suggesting a potential role in sperm function. We conclude that while all palindrome-associated gene families are not essential for male fertility, large palindromes influence the evolution of their associated gene families.


Assuntos
Cromossomos Sexuais , Espermatogênese , Animais , Fertilidade/genética , Masculino , Mamíferos/genética , Camundongos , Espermatogênese/genética , Espermatozoides , Testículo/metabolismo
7.
Biol Lett ; 18(5): 20220058, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35506236

RESUMO

Male-male competition after mating (sperm competition) favours adaptations in male traits, such as elevated sperm numbers facilitated by larger testes. Ultimately, patterns of female distribution will affect the strength of sperm competition by dictating the extent to which males are able to prevent female remating. Despite this, our understanding of how the spatial and temporal distributions of mating opportunities have shaped the evolutionary course of sperm competition is limited. Here, we use phylogenetic comparative methods to explore interspecific variation in testes size in relation to patterns of female distribution in Australian rodents. We find that as mating season length (temporal distribution of females) increases, testes size decreases, which is consistent with the idea that it is difficult for males to prevent females from remating when overlap among oestrous females is temporally concentrated. Additionally, we find that social species (spatially clustered) have smaller testes than non-social species (spatially dispersed). This result suggests that males may be effective in monopolizing reproduction within social groups, which leads to reduced levels of sperm competition relative to non-social species where free-ranging females cannot be controlled. Overall, our results show that patterns of female distribution, in both space and time, can influence the strength of post-mating sexual selection among species.


Assuntos
Espermatozoides , Testículo , Animais , Austrália , Feminino , Masculino , Filogenia , Roedores
8.
J Vis Exp ; (182)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35532241

RESUMO

The conventional semen parameter analysis is widely used to assess male fertility. However, studies have found that ~15% of infertile patients show no abnormalities in conventional semen parameters. Additional technologies are needed to explain the idiopathic infertility and detect subtle sperm defects. Currently, biomarkers of sperm function, including sperm apoptosis, mitochondrial membrane potential (MMP), and DNA damage, reveal sperm physiology at the molecular level and are capable of predicting male fertility. With flow cytometry (FCM) techniques, each of these markers can be rapidly, accurately, and precisely measured in human semen samples, but time costs substantially increase and results could be obstructed if all the biomarkers need to be tested with a single cytometer. In this protocol, after collection and immediate incubation at 37 °C for liquefication, semen samples were further analyzed for sperm apoptosis using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. The MMP was labeled with 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolylcarbocyanine iodide (JC-1) probe, and DNA damage was assessed using the sperm chromatin structure assay (SCSA) with acridine orange (AO) staining. Thus, flow cytometric analysis of sperm function markers can be a practical and reliable toolkit for the diagnosis of infertility and evaluation of sperm function at both bench and bed.


Assuntos
Infertilidade , Espermatozoides , Biomarcadores , Cromatina , Citometria de Fluxo/métodos , Humanos , Masculino , Metaloproteinases da Matriz
10.
Asian J Androl ; 24(3): 260-265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35532568

RESUMO

Obtaining high-quality embryos is one of the key factors to improve the clinical pregnancy rate of assisted reproductive technologies (ART). So far, the clinical evaluation of embryo quality depends on embryo morphology. However, the clinical pregnancy rate is still low. Therefore, new indicators are needed to further improve the evaluation of embryo quality. Several studies have shown that the decrease of sperm-specific protein actin-like 7A (ACTL7A) leaded to low fertilization rate, poor embryo development, and even infertility. The aim of this study was to study whether the different expression levels of ACTL7A on sperm can be used as a biomarker for predicting embryo quality. In this study, excluding the factors of severe female infertility, a total of 281 sperm samples were collected to compare the ACTL7A expression levels of sperms with high and low effective embryo rates and analyze the correlation between protein levels and in-vitro fertilization (IVF) laboratory outcomes. Our results indicated that the ACTL7A levels were significantly reduced in sperm samples presenting poor embryo quality. Furthermore, the protein levels showed a significant correlation with fertilization outcomes of ART. ACTL7A has the potential to be a biomarker for predicting success rate of fertilization and effective embryo and the possibility of embryo arrest. In conclusion, sperm-specific protein ACTL7A has a strong correlation with IVF laboratory outcomes and plays important roles in fertilization and embryo development.


Assuntos
Fertilização In Vitro , Técnicas de Reprodução Assistida , Biomarcadores/metabolismo , Feminino , Fertilização , Humanos , Masculino , Gravidez , Taxa de Gravidez , Espermatozoides/metabolismo
11.
Medicine (Baltimore) ; 101(17): e29193, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35512075

RESUMO

ABSTRACT: Although many studies suggest that varicocelectomy leads to improvement in semen parameters and morphology, its clinical efficacy remains controversial. The detailed morphological parameters described in the World Health Organization guidelines are important in terms of showing the effect of microsurgical subinguinal varicocelectomy on morphological changes.An observational, retrospective clinical cohort study was conducted with patients followed up from January 2018 to August 2021. This study included the data of 79 patients who met the criterion of undergoing at least 2 detailed morphological evaluations before and after surgery. All operations were performed by the same surgical team using the microsurgical subinguinal varicocelectomy technique.The mean age of the patients was 30.25 years. Of the patients, 63 underwent left-sided varicocelectomy and 16 underwent bilateral surgery. The sperm analysis revealed statistically significant increases in sperm volume (P = .006), sperm concentration (P = .003), total sperm count (P = .001), progressive sperm motility (P < .001), and normal morphology (P < .001). In the detailed morphological evaluation, except for the elongated head anomaly (P = .037), no other statistically significant changes were found in relation to sperm head, tail, and neck anomalies after surgery.This study makes an important contribution to the literature, being the first to use the subinguinal microscopic varicocelectomy technique in detailed morphological semen evaluation. We consider that detailed morphology examination in the selection and treatment of infertile patients may be useful in evaluating the efficacy of varicocelectomy.


Assuntos
Infertilidade Masculina , Varicocele , Adulto , Estudos de Coortes , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/cirurgia , Masculino , Microcirurgia/métodos , Estudos Retrospectivos , Contagem de Espermatozoides , Motilidade Espermática , Espermatozoides , Varicocele/cirurgia
12.
J Int Med Res ; 50(5): 3000605221097492, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35545843

RESUMO

OBJECTIVE: This study was performed to determine the effect of swim-up (SU) and density gradient centrifugation (DGC) on sperm survival and DNA fragmentation. METHODS: Individual semen samples were analyzed before each was divided into two aliquots (half for SU and half for DGC) for calculation of sperm survival and the DNA fragmentation index (DFI). Sperm DNA fragmentation was determined using the sperm chromatin dispersion test. RESULTS: The DFI of the 63 semen samples processed using both procedures was lower than that of the fresh semen samples. The DFI was significantly lower for samples processed using the SU than DGC method. In the sperm survival test, the SU technique was associated with increased sperm motility and vitality following preparation. After 24 hours, however, the concentration and percentage of surviving sperm were significantly lower in the SU than DGC group. CONCLUSIONS: Both semen preparation techniques help to minimize sperm DNA fragmentation; however, when the DFI is <30%, the SU technique is more appropriate than DGC. While DGC may be superior for intrauterine insemination, the SU method may be preferable for in vitro fertilization or maturation.


Assuntos
Análise do Sêmen , Motilidade Espermática , Centrifugação com Gradiente de Concentração/métodos , Fragmentação do DNA , Humanos , Masculino , Análise do Sêmen/métodos , Espermatozoides
13.
Front Endocrinol (Lausanne) ; 13: 893863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600600

RESUMO

Perinatal exposure to smoking has been associated with childhood asthma, one of the most common pediatric conditions affecting millions of children globally. Of great interest, this disease phenotype appears heritable as it can persist across multiple generations even in the absence of persistent exposure to smoking in subsequent generations. Although the molecular mechanisms underlying childhood asthma induced by perinatal exposure to smoking or nicotine remain elusive, an epigenetic mechanism has been proposed, which is supported by the data from our earlier analyses on germline DNA methylation (5mC) and histone marks (H3 and H4 acetylation). To further investigate the potential epigenetic inheritance of childhood asthma induced by perinatal nicotine exposure, we profiled both large and small RNAs in the sperm of F1 male rats. Our data revealed that perinatal exposure to nicotine leads to alterations in the profiles of sperm-borne RNAs, including mRNAs and small RNAs, and that rosiglitazone, a PPARγ agonist, can attenuate the effect of nicotine and reverse the sperm-borne RNA profiles of F1 male rats to close to placebo control levels.


Assuntos
Asma , Nicotina , Animais , Asma/induzido quimicamente , Feminino , Humanos , Masculino , Nicotina/efeitos adversos , Gravidez , RNA , Ratos , Ratos Sprague-Dawley , Espermatozoides
15.
Ying Yong Sheng Tai Xue Bao ; 33(4): 1131-1136, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543069

RESUMO

Bisphenol A (BPA) is a synthetic estrogen compound, which widely exists in the environment, interferes with mammalian endocrine and affects the function of reproductive system of males. Taking fresh sperm of boar, 17 ℃ preservation boar sperm, and mouse sperm as test materials, we examined the effects of BPA (0, 0.1,1,10,100 µmol∙L-1) on proteins tyrosine phosphorylation in sperm and the molecular mechanism by using wes-tern blot (WB) and immunofluorescence techniques coupled to in vitro culture method. The results showed that low BPA concentration (0.1, 1 µmol∙L-1) markedly accelerated the protein tyrosine phosphorylation of fresh boar capacitated sperm. However, the tyrosine phosphorylation of boar sperm decreased in high BPA concentration (10, 100 µmol∙L-1). The tyrosine phosphorylation of the mouse sperm raised with the increases of BPA concentration. Moreover, BPA affected different kinds of proteins related to tyrosine phosphorylation modification of porcine and mouse sperm capacitation, suggesting that the effect of BPA exposure on mammalian sperm was species-specific. Furthermore, the results of immunofluorescence showed that the effects of BPA on protein tyrosine phosphorylation in sperm mainly occurred in the middle and principal piece of flagellum.


Assuntos
Capacitação Espermática , Espermatozoides , Animais , Compostos Benzidrílicos , Masculino , Mamíferos/metabolismo , Camundongos , Fenóis , Fosforilação , Proteínas , Suínos , Tirosina
16.
Anim Sci J ; 93(1): e13732, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35543176

RESUMO

The first filial generation of the cattleyaks demonstrates hybrid vigor; however, the male cattleyaks are infertile and restrict productivity and breeding. The discovery of genes in a segment-specific approach offers valuable information and understanding concerning fertility status, yet the biology of cattleyak epididymis is still progressing. Comparative transcriptome analysis was performed on segment pairs of cattleyak epididymis. The caput versus corpus epididymis provided the highest (57.8%) differentially expressed genes (DEGs), corpus versus cauda (25.1%) followed, whereas caput versus cauda pair (17.1%) had the least DEGs. The expression levels of genes coding EPHB6, TLR1, MUC20, MT3, INHBB, TRPV5, EI24, PAOX, KIF12, DEPDC5, and KRT25, which might have the potentials to regulate the homeostasis, innate immunity, differentiation, motility, transport, and sperm maturation-related function in epididymal cells, were downregulated in the distal segment of epididymis. Top enriched KEGG pathways included mTOR, axon guidance, and taste transduction signaling pathways. EIF4B, EPHB6, and TAS2R42 were enriched in the pathways, respectively. Identifying key, new, and unexplored DEGs among the epididymal segments and further analyzing them could boost cattleyak fertility by maximizing sperm quality from genetically better sires and also facilitate better understanding of the epididymal biology.


Assuntos
Epididimo , Maturação do Esperma , Animais , Epididimo/metabolismo , Perfilação da Expressão Gênica/veterinária , Masculino , RNA-Seq/veterinária , Maturação do Esperma/genética , Espermatozoides/metabolismo
17.
Sci Rep ; 12(1): 6446, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440797

RESUMO

Fertilizing sperm are retained by adhesion to specific glycans on the epithelium of the oviduct forming a reservoir before sperm are released from the reservoir so fertilization can ensue. Capacitated sperm lose affinity for the oviduct epithelium but the components of capacitation that are important for sperm release are uncertain. One important correlate of capacitation is the development of hyperactivated motility. Hyperactivation is characterized by asymmetrical flagellar beating with high beat amplitude. We tested whether the development of full-type asymmetrical motility was sufficient to release sperm from immobilized oviduct glycans. Sperm hyperactivation was induced by four different compounds, a cell-permeable cAMP analog (cBiMPS), CatSper activators (4-aminopyridine and procaine), and an endogenous steroid (progesterone). Using standard analysis (CASA) and direct visualization with high-speed video microscopy, we first confirmed that all four compounds induced hyperactivation. Subsequently, sperm were allowed to bind to immobilized oviduct glycans, and compounds or vehicle controls were added. All compounds caused sperm release from immobilized glycans, demonstrating that hyperactivation was sufficient to release sperm from oviduct cells and immobilized glycans. Pharmacological inhibition of the non-genomic progesterone receptor and CatSper diminished sperm release from oviduct glycans. Inhibition of the proteolytic activities of the ubiquitin-proteasome system (UPS), implicated in the regulation of sperm capacitation, diminished sperm release in response to all hyperactivation inducers. In summary, induction of sperm hyperactivation was sufficient to induce sperm release from immobilized oviduct glycans and release was dependent on CatSper and the UPS.


Assuntos
Oviductos , Motilidade Espermática , Animais , Feminino , Humanos , Masculino , Oviductos/metabolismo , Polissacarídeos/metabolismo , Capacitação Espermática/fisiologia , Motilidade Espermática/fisiologia , Espermatozoides/metabolismo , Suínos
18.
Biochem J ; 479(9): 953-972, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35419597

RESUMO

Chromatin remodelling in spermatids is an essential step in spermiogenesis and involves the exchange of most histones by protamines, which drives chromatin condensation in late spermatids. The gene Rimklb encodes a citrylglutamate synthase highly expressed in testes of vertebrates and the increase of its reaction product, ß-citrylglutamate, correlates in time with the appearance of spermatids. Here we show that deficiency in a functional Rimklb gene leads to male subfertility, which could be partially rescued by in vitro fertilization. Rimklb-deficient mice are impaired in a late step of spermiogenesis and produce spermatozoa with abnormally shaped heads and nuclei. Sperm chromatin in Rimklb-deficient mice was less condensed and showed impaired histone to protamine exchange and retained transition protein 2. These observations suggest that citrylglutamate synthase, probably via its reaction product ß-citrylglutamate, is essential for efficient chromatin remodelling during spermiogenesis and may be a possible candidate gene for male subfertility or infertility in humans.


Assuntos
Infertilidade Masculina , Espermátides , Animais , Cromatina/genética , Cromatina/metabolismo , Proteínas Cromossômicas não Histona , Histonas/genética , Histonas/metabolismo , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Protaminas/genética , Protaminas/metabolismo , Espermátides/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo
19.
Sci Rep ; 12(1): 5452, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440735

RESUMO

Environmental toxicants have been shown to promote the epigenetic transgenerational inheritance of disease through exposure specific epigenetic alterations in the germline. The current study examines the actions of hydrocarbon jet fuel, dioxin, pesticides (permethrin and methoxychlor), plastics, and herbicides (glyphosate and atrazine) in the promotion of transgenerational disease in the great grand-offspring rats that correlates with specific disease associated differential DNA methylation regions (DMRs). The transgenerational disease observed was similar for all exposures and includes pathologies of the kidney, prostate, and testis, pubertal abnormalities, and obesity. The disease specific DMRs in sperm were exposure specific for each pathology with negligible overlap. Therefore, for each disease the DMRs and associated genes were distinct for each exposure generational lineage. Observations suggest a large number of DMRs and associated genes are involved in a specific pathology, and various environmental exposures influence unique subsets of DMRs and genes to promote the transgenerational developmental origins of disease susceptibility later in life. A novel multiscale systems biology basis of disease etiology is proposed involving an integration of environmental epigenetics, genetics and generational toxicology.


Assuntos
Metilação de DNA , Epigênese Genética , Animais , Padrões de Herança/genética , Masculino , Ratos , Ratos Sprague-Dawley , Espermatozoides/metabolismo
20.
Reprod Fertil Dev ; 34(8): 633-643, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35361312

RESUMO

AIM: We examined four single nucleotide polymorphisms in four antioxidant genes (PON1 , CAT , GPx1 and SOD2 ) in 100 infertility cases and 100 controls from an Iranian population-based case-control study to confirm the assumption that polymorphisms in oxidative stress genes increase the risk of sperm DNA damage and idiopathic male infertility. METHODS: Restriction fragment length polymorphism and tetra-primer amplification refractory mutation system PCR were used to identify genotypes. Sperm DNA damage was assessed using the Sperm Chromatin Dispersion test (Halo Sperm), and the total antioxidant capacity of seminal fluid was determined using the FRAP assay. KEY RESULTS: Our findings demonstrated that alleles Arg-PON1 (rs662) and Ala-MnSOD (rs4880) variant genotypes were considerably linked with a higher risk of male infertility. CONCLUSIONS: Linear regression analysis revealed that those with the PON1 Gln192Arg or SOD2 Val16Ala variants have significantly higher levels of sperm DNA fragmentation and lower levels of the total antioxidant capacity in seminal fluid. IMPLICATIONS: These findings suggest that genetic differences in antioxidant genes may be linked to oxidative stress, sperm DNA damage, and idiopathic male infertility.


Assuntos
Infertilidade Masculina , Polimorfismo de Nucleotídeo Único , Antioxidantes/metabolismo , Arildialquilfosfatase/genética , Arildialquilfosfatase/metabolismo , Estudos de Casos e Controles , Dano ao DNA , Humanos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Irã (Geográfico)/epidemiologia , Masculino , Estresse Oxidativo/genética , Espermatozoides/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA