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1.
Nat Commun ; 11(1): 5417, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110091

RESUMO

De novo DNA methylation (DNAme) during mammalian spermatogenesis yields a densely methylated genome, with the exception of CpG islands (CGIs), which are hypomethylated in sperm. While the paternal genome undergoes widespread DNAme loss before the first S-phase following fertilization, recent mass spectrometry analysis revealed that the zygotic paternal genome is paradoxically also subject to a low level of de novo DNAme. However, the loci involved, and impact on transcription were not addressed. Here, we employ allele-specific analysis of whole-genome bisulphite sequencing data and show that a number of genomic regions, including several dozen CGI promoters, are de novo methylated on the paternal genome by the 2-cell stage. A subset of these promoters maintains DNAme through development to the blastocyst stage. Consistent with paternal DNAme acquisition, many of these loci are hypermethylated in androgenetic blastocysts but hypomethylated in parthenogenetic blastocysts. Paternal DNAme acquisition is lost following maternal deletion of Dnmt3a, with a subset of promoters, which are normally transcribed from the paternal allele in blastocysts, being prematurely transcribed at the 4-cell stage in maternal Dnmt3a knockout embryos. These observations uncover a role for maternal DNMT3A activity in post-fertilization epigenetic reprogramming and transcriptional silencing of the paternal genome.


Assuntos
Blastocisto/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Genoma , Herança Materna , Herança Paterna , Alelos , Animais , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Epigenômica , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos Endogâmicos DBA , Oócitos/metabolismo , Espermatozoides/metabolismo
2.
Nat Commun ; 11(1): 4505, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908148

RESUMO

Evidence for transgenerational inheritance of epigenetic information in vertebrates is scarce. Aberrant patterns of DNA methylation in gametes may set the stage for transmission into future generations. Here, we describe a viable hypomorphic allele of dnmt1 in zebrafish that causes widespread demethylation of CpG dinucleotides in sperm and somatic tissues. We find that homozygous mutants are essentially normal, with the exception of drastically impaired lymphopoiesis, affecting both larval and adult phases of T cell development. The phenotype of impaired larval (but not adult) T cell development is transmitted to subsequent generations by genotypically wildtype fish. We further find that about 200 differentially methylated regions in sperm DNA of transmitting and non-transmitting males, including hypermethylated sites associated with runx3 and rptor genes, whose reduced activities are associated with impaired larval T cell development. Our results indicate a particular sensitivity of larval T cell development to transgenerationally inherited epimutations.


Assuntos
Diferenciação Celular/genética , Genes Recessivos , Larva/crescimento & desenvolvimento , Linfopoese/genética , Linfócitos T/fisiologia , Alelos , Animais , Animais Geneticamente Modificados , Subunidade alfa 3 de Fator de Ligação ao Core/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA , Epigênese Genética , Feminino , Genética , Larva/citologia , Masculino , Mutação , Proteína Regulatória Associada a mTOR/genética , Espermatozoides/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
3.
Nat Genet ; 52(10): 1088-1098, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32929285

RESUMO

De novo DNA methylation (DNAme) in mammalian germ cells is dependent on DNMT3A and DNMT3L. However, oocytes and spermatozoa show distinct patterns of DNAme. In mouse oocytes, de novo DNAme requires the lysine methyltransferase (KMTase) SETD2, which deposits H3K36me3. We show here that SETD2 is dispensable for de novo DNAme in the male germline. Instead, the lysine methyltransferase NSD1, which broadly deposits H3K36me2 in euchromatic regions, plays a critical role in de novo DNAme in prospermatogonia, including at imprinted genes. However, males deficient in germline NSD1 show a more severe defect in spermatogenesis than Dnmt3l-/- males. Notably, unlike DNMT3L, NSD1 safeguards a subset of genes against H3K27me3-associated transcriptional silencing. In contrast, H3K36me2 in oocytes is predominantly dependent on SETD2 and coincides with H3K36me3. Furthermore, females with NSD1-deficient oocytes are fertile. Thus, the sexually dimorphic pattern of DNAme in mature mouse gametes is orchestrated by distinct profiles of H3K36 methylation.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Histona-Lisina N-Metiltransferase/genética , Espermatogênese/genética , Animais , Metilação de DNA/genética , Feminino , Histona-Lisina N-Metiltransferase/deficiência , Histonas/genética , Humanos , Masculino , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Proteínas do Grupo Polycomb/genética , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/metabolismo , Fatores de Transcrição/genética
4.
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
5.
PLoS One ; 15(8): e0237666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822385

RESUMO

Before fertilization, sperm bind to epithelial cells of the oviduct isthmus to form a reservoir that regulates sperm viability and capacitation. The sperm reservoir maintains optimum fertility in species, like swine, in which semen deposition and ovulation may not be well synchronized. We demonstrated previously that porcine sperm bind to two oviductal glycan motifs, a biantennary 6-sialylated N-acetyllactosamine (bi-SiaLN) oligosaccharide and 3-O-sulfated Lewis X trisaccharide (suLeX). Here, we assessed the ability of these glycans to regulate sperm Ca2+ influx, capacitation and affect sperm lifespan. After 24 h, the viability of sperm bound to immobilized bi-SiaLN and suLeX was higher (46% and 41% respectively) compared to viability of free-swimming sperm (10-12%). Ca2+ is a central regulator of sperm function so we assessed whether oviduct glycans could affect the Ca2+ influx that occurs during capacitation. Using a fluorescent intracellular Ca2+ probe, we observed that both oviduct glycans suppressed the Ca2+ increase that occurs during capacitation. Thus, specific oviduct glycans can regulate intracellular Ca2+. Because the increase in intracellular Ca2+ was suppressed by oviduct glycans, we examined whether glycans affected capacitation, as determined by protein tyrosine phosphorylation and the ability to undergo a Ca2+ ionophore-induced acrosome reaction. We found no discernable suppression of capacitation in sperm bound to oviduct glycans. We also detected no effect of oviduct glycans on sperm motility during capacitation. In summary, LeX and bi-SiaLN glycan motifs found on oviduct oligosaccharides suppress the Ca2+ influx that occurs during capacitation and extend sperm lifespan but do not affect sperm capacitation or motility.


Assuntos
Cálcio/metabolismo , Oviductos/metabolismo , Polissacarídeos/metabolismo , Espermatozoides/metabolismo , Suínos/fisiologia , Animais , Sobrevivência Celular , Feminino , Masculino , Análise do Sêmen , Capacitação Espermática , Motilidade Espermática
6.
Gene ; 760: 145029, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758578

RESUMO

Heat shock protein 70 (HSP70) has been widely reported to play a vital role in maintaining intracellular homeostasis, mainly through cellular protection and immune regulation. The expression and function of HSP70 can vary depending upon species and age. To explore the expression signatures and regulatory functions of HSP70 in the reproductive organs of male sheep, we evaluated the expression and distribution patterns of HSP70 in the testes and epididymides (caput, corpus, and cauda) of Tibetan sheep at three developmental stages (i.e., 3 months, 1 year and 3 years after birth) by qRT-PCR, Western blot and immunofluorescence. HSP70 was found to be expressed in testes, caput, corpus, and cauda epididymides throughout the developmental stages but is mainly expressed postpuberty (1 year and 3 years old). Immunofluorescence results revealed that in the testes, a positive reaction for HSP70 protein was mainly seen in round spermatids and luminal sperms from the groups aged 1 year and 3 years. In caput epididymides, the positive signals for HSP70 protein was notably observed in sperm and principal cells of the epididymal epithelium from the groups aged 1 year and 3 years, and positive signals in the epididymal interstitium were found in all three age groups. In corpus and cauda epididymides, HSP70 protein was present in the epididymal epithelium and interstitium, and the positive signals gradually increased with age. In conclusion, these findings suggest that Tibetan sheep HSP70 may play a crucial role in further development and maturation of postmeiotic germ cells and participate in regulation of intraepididymal homeostasis maintenance in Tibetan sheep.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Genitália/crescimento & desenvolvimento , Proteínas de Choque Térmico HSP70/metabolismo , Animais , Epididimo/metabolismo , Genitália/metabolismo , Proteínas de Choque Térmico HSP70/genética , Masculino , Ovinos , Carneiro Doméstico/metabolismo , Espermátides/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo
7.
Life Sci ; 258: 118192, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781062

RESUMO

The present study was conducted to identify possible health - promoting effects of wogonin (Wog) on testicular dysfunction in rats caused by cadmium. Pre-treatment of cadmium chloride (Cd: 5 mg/kg b.wt.) administered rats with wogonin (10 mg/kg b.wt) resulted in significant improvement in Cd-induced decrease in body and organ (testes and epididymides) weights. Wogonin treatment significantly improved Cd-induced reduction in sperm quality and quantity, steroidogenic gene (SFI, StAR, CYP11A1, 3ß-HSD, CYP17A1 and 17ß-HSD) and protein (SF1, StAR and CYP17A1) expressions and serum testosterone levels. Wogonin treatment provided significant protection to Cd-induced aggression in testicular oxidative (elevated levels of MDA) and anti-oxidative (diminished activities of SOD, CAT and GPx) status. Wog significantly up-regulated mRNA levels of Nrf2, NQO1 and HO-1 and down-regulation of Keap1 in cadmium treated testes. Wogonin administration significantly suppressed Cd-stimulated increase in inflammatory reactions (increase in NF-κB p65 DNA, p-IKKß, TNF-α levels and decrease in IL-10 levels). Wogonin prevented apoptotic damage by enhanced protein distribution of caspase-9, caspase-3, and Bax due to Cd exposure. Furthermore, Wogonin presented significant protection to histo-morphometric changes resulted after Cd administration. Taken together, the findings of this study provided clear evidence of the therapeutic potential of Cd-induced testicular toxicity at least partly due to its antioxidant, anti-inflammatory and anti-apoptotic properties.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Flavanonas/farmacologia , Substâncias Protetoras/farmacologia , Transdução de Sinais , Testículo/patologia , Animais , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Ingestão de Líquidos/efeitos dos fármacos , Epididimo/efeitos dos fármacos , Epididimo/patologia , Comportamento Alimentar/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônios/sangue , Inflamação/patologia , Masculino , Oxirredução , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Esteroides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
8.
Nat Protoc ; 15(8): 2645-2667, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32681149

RESUMO

The preferred sex of livestock differs among breeders; for example, dairy farmers prefer female calves for the production of milk, whereas cattle meat producers often prefer males. Sexing of laboratory animals is also beneficial in some research fields, including reproductive biology and metabolic studies. Most sexing methods separate X sperm and Y sperm with a cell sorter. Here, we describe a system in which treatment with the TLR7/8 ligand (R848) separates X sperm from Y sperm. Because this protocol does not require any special equipment or professional skills, it can be easily applied in laboratories where in vitro fertilization (IVF) is performed. The sperm are treated with 0.03 µM R848 in 1 mL of modified human tubal fluid (mHTF) medium (mouse sperm) or 3 mL of mHTF medium (bull sperm) for 60 min, and then the upper layer (400 µL in mouse sperm or 1 mL in bull sperm) and the precipitate are separately collected. After each sample is washed by centrifugation, the sperm are suspended in ligand-free IVF medium and can then be used for IVF. More than 90% of the embryos made with upper-layer sperm are XY in both mice and cattle, and >80% of the embryos made with precipitated sperm are XX in both species. Separation of X sperm and Y sperm for IVF can be completed within 2 h.


Assuntos
Pré-Seleção do Sexo/métodos , Espermatozoides/metabolismo , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/metabolismo , Cromossomo X/metabolismo , Cromossomo Y/metabolismo , Animais , Bovinos , Feminino , Masculino , Camundongos
9.
PLoS One ; 15(7): e0235789, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645117

RESUMO

Eisenia andrei (Ea) and E. fetida (Ef) lumbricid earthworms are simultaneous hermaphrodites potentially capable of self-fertilization and hybridization. We have shown previously that reproductive isolation in these species is incomplete in Ea and Ef earthworms of French provenance, as viable offspring appeared in inter-specific pairs. Fertile asymmetric hybrids developed from Ea-derived ova fertilized by Ef-derived spermatozoa, as well as Ea or Ef specimens derived after self-fertilization (resulting from admixture of endogenously produced spermatozoa with sperm from a partner), but never Ef-hybrids from Ef-ova fertilized by Ea-spermatozoa. The latter appeared only in backcrosses of Ea-hybrids with the Ef. Here we show that these phenomena are not unique for French Ea/Ef earthworms, but are shared by earthworms from French, Hungarian, and Polish laboratory cultures. Semi-quantitative studies on fertility of Ea-derived hybrids revealed gradually decreasing numbers of offspring in three successive generations, more rapid in backcrosses with Ef than with Ea, and the absence of progeny in pairs of hybrids, despite the presence of cocoons in almost all pairs. Based on species specific mitochondrial and nuclear DNA sequences, we provide the first examples of two unique sterile hybrids with mitonuclear mismatch and potential mitonuclear incompatibility among offspring of one of the hybrid+Ef pairs. Earthworms from the investigated populations did not reproduce when kept from hatching in isolation or with representatives of Dendrobaena veneta but started reproducing upon recognition of a related partner, such as Ea, Ef or their hybrids. The existence of Ea or Ef specimens among offspring of hybrid+Ea/Ef pairs might be explained either by partner-induced self-fertilization of Ea/Ef or hybrid-derived ova, or by cross-fertilization of Ea/Ef /hybrid ova by partner-derived spermatozoa; the latter might contribute to interspecific gene introgression.


Assuntos
Oligoquetos/fisiologia , Animais , Feminino , Fertilidade , Fertilização , França , Hungria , Hibridização Genética , Masculino , Oligoquetos/genética , Polônia , Reprodução , Isolamento Reprodutivo , Especificidade da Espécie , Espermatozoides/metabolismo
10.
Cytogenet Genome Res ; 160(6): 295-308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32683365

RESUMO

Intramolecular coevolution of amino acid sites has repeatedly been studied to improve predictions on protein structure and function. Thereby, the focus was on bacterial proteins with available crystallographic data. However, intramolecular coevolution has not yet been compared between protein sets along a gradient of functional proximity to fertilization. This is especially true for the potential effect of external selective forces on intraprotein coevolution. In this study, we investigated both aspects in equally sized sets of mammalian proteins representing spermatozoa, testis, entire body, and liver. For coevolutionary analyses, we derived the proportion of covarying sites per protein from amino acid alignments of 10 mammalian orthologues each. In confirmation of the validity of our coevolution proxy, we found positive associations with the nonsynonymous or amino acid substitution rate in all protein sets. However, our coevolution proxy negatively correlated with the number of protein interactants (node degree) in male reproductive protein sets alone. In addition, a negative association of our coevolution proxy with protein hydrophobicity was significant in sperm proteins only. Accordingly, the restrictive effect of protein interactants was most pronounced in male reproductive proteins, and the tendency of sperm proteins to form internal structures decreased the more coevolutionary sites they had. Both aspects illustrate that the share of outward and thus functional coevolution increases with greater proximity to fertilization. We found this conclusion confirmed by additional comparisons within sperm proteins. Thus, sperm proteins with high hydrophobicity had the lowest proportions of covarying sites and, according to gene annotations, localized more frequently to internal cellular structures. They should therefore be less exposed to postcopulatory forms of sexual selection. Their counterparts with low hydrophobicity had larger proportions of covarying sites and more often resided at the cell membrane or were secreted. At the cellular level, they are thus closer to externally induced forces of postcopulatory selection which are known for their potential to increase substitution rates. In addition, we show that the intermediary status of the testicular protein set in correlation analyses is probably due to a special combination of reproductive and somatic involvements.


Assuntos
Evolução Molecular , Fertilização , Proteínas/química , Proteínas/metabolismo , Espermatozoides/química , Espermatozoides/metabolismo , Animais , Doença , Fertilização/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas/genética , Proteoma/química , Proteoma/metabolismo , Suínos
12.
Aquat Toxicol ; 226: 105580, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32712368

RESUMO

Bisphenol A (BPA), a well-known estrogenic endocrine disruptor, is ubiquitously present in the environment, possessing the potential to interfere with the reproductive endocrine system in male mammals. However, there are limited studies on the reproductive toxicity in male aquatic animals associated with epigenetic modifications. In order to evaluate the potential effects of BPA on reproduction and better understand the underlying mechanism, adult male rare minnow (Gobiocypris rarus) were exposed to 15 µg L-1 BPA over a period of 63 d. Results showed that BPA induced congestion of blood vessels and infiltration of inflammatory cells after 21 d exposure, and decreased sperm fertilization after 63 d exposure. The genome DNA methylation levels were significantly increased throughout the treatment, and a strong positive stain were found in the spermatocyte, spermatid and sperm. The H3K4me3 level in all types of germ cell were increased by 21 d exposure while decreased following 63 d exposure. The positive stain of H3K9me3 was decreased in sperms while increased in spermatids by 21 d exposure. In addition, the H3K9me3 level was significantly increased after 63 d exposure, and a strong positive stain were found in spermatocytes, spermatids, and sperms. Our result also revealed that the transcripts of DNA methyltransferase genes (dnmt1 and dnmt3-8) and histone methyltransferase genes (mll2-5, setdb1-2 and ezh2) were also markedly changed under BPA exposure for 21-63 d. These findings indicated that BPA had toxicity in male reproductive, and DNA/histone methylation might play a vital role in the regulation of BPA-triggered the decreased of sperm quality.


Assuntos
Compostos Benzidrílicos/toxicidade , Cyprinidae/metabolismo , Metilação de DNA/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Histonas/metabolismo , Fenóis/toxicidade , Espermatozoides/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , DNA/metabolismo , Feminino , Humanos , Masculino , Análise do Sêmen , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos
13.
Science ; 368(6495): 1132-1135, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32499443

RESUMO

The lumicrine system is a postulated signaling system in which testis-derived (upstream) secreted factors enter the male reproductive tract to regulate epididymal (downstream) pathways required for sperm maturation. Until now, no lumicrine factors have been identified. We demonstrate that a testicular germ-cell-secreted epidermal growth factor-like protein, neural epidermal growth factor-like-like 2 (NELL2), specifically binds to an orphan receptor tyrosine kinase, c-ros oncogene 1 (ROS1), and mediates the differentiation of the initial segment (IS) of the caput epididymis. Male mice in which Nell2 had been knocked out were infertile. The IS-specific secreted proteases, ovochymase 2 (OVCH2) and A disintegrin and metallopeptidase 28 (ADAM28), were expressed upon IS maturation, and OVCH2 was required for processing of the sperm surface protein ADAM3, which is required for sperm fertilizing ability. This work identifies a lumicrine system essential for testis-epididymis-spermatozoa (NELL2-ROS1-OVCH2-ADAM3) signaling and male fertility.


Assuntos
Comunicação Celular/fisiologia , Endopeptidases/metabolismo , Epididimo/metabolismo , Fertilidade , Infertilidade Masculina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Proteínas ADAM/metabolismo , Animais , Comunicação Celular/genética , Endopeptidases/genética , Infertilidade Masculina/genética , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo
14.
Life Sci ; 256: 117895, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502545

RESUMO

AIMS: We aimed to investigate the effect of sperm miR-34c on early human embryonic development kinetics and clinical outcomes of in vitro fertilization (IVF) patients. MATERIALS AND METHODS: After oocyte insemination, residual sperm specimens were collected from 58 patients undergoing IVF. miR-34c expression levels in sperm, oocytes, zygotes, and embryos/blastocysts were detected with qRT-PCR, and embryonic development kinetics were observed using time-lapse technology. To confirm the role of miR-34c in regulation of early embryonic development, miR-34c siRNA was injected into zygotes obtained from in vitro-matured oocytes. A ROC curve was used to determine the cutoff value. Comparisons of embryonic development kinetics and clinical outcomes were performed according to the cutoff value. KEY FINDINGS: The miR-34c expression level was highest in 3PN zygotes, but was not expressed in human oocytes. In the miR-34c siRNA group, embryonic development kinetic parameters t2, t3, t4, and t5 were significantly prolonged, but the cleavage rate and high-quality embryo rate were lower than in the control group. The levels of sperm miR-34c were negatively correlated with t5 and positively correlated with rates of blastocyst formation, high-quality blastocysts, and pregnancy. The miR-34c levels and the blastocyst formation rate were higher in the pregnancy group (p < 0.05). Logistic regression analysis showed that sperm miR-34c level was significantly correlated with pregnancy (OR: 5.056, 95% CI: 1.560-16.384; p = 0.007). SIGNIFICANCE: The sperm miR-34c expression level is associated with embryonic development kinetics and clinical outcomes. Thus, miR-34c expression is beneficial to embryonic development and may be used as an indicator of IVF outcomes.


Assuntos
Desenvolvimento Embrionário , MicroRNAs/metabolismo , Espermatozoides/metabolismo , Adulto , Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Cinética , Masculino , MicroRNAs/genética , Oócitos/metabolismo , Gravidez , Curva ROC
15.
Int J Nanomedicine ; 15: 3415-3431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523341

RESUMO

Purpose: Lanthanum oxide (La2O3) nanoparticles (NPs) have been widely used in catalytic and photoelectric applications, but the reproductive toxicity is still unclear. This study evaluated the reproductive toxicity of two different-sized La2O3 particles in the testes. Materials and Methods: Fifty Kunming mice were randomly divided into five groups. Mice were treated with La2O3 NPs by repeated intragastric administration for 90 days (control, nano-sized with 5, 10, 50 mg/kg BW and micro-sized with 50 mg/kg BW). Mice in the control group were treated with de-ionised water without La2O3 NPs. Sperm parameters, testicular histopathology, TEM assessment, hormone assay and nuclear factor erythroid 2-related factor 2 (Nrf-2) pathway were performed and evaluated. Results: The body weight of mice treated with La2O3 NPs or not had no difference; sperm parameters and histological assessment showed that La2O3 NPs could induce reproductive toxicity in the testicle. Serum testosterone and gonadotropin-releasing hormone (GnRH) in the NH (nano-sized with 50 mg/kg BW) group were markedly decreased relative to control group, and an increase of luteinizing hormone (LH) in NH group was detected . Additionally, transmission electron microscopy revealed that the ultrastructural abnormalities induced by La2O3 NPs were more severe than La2O3 MPs in the testes. Furthermore, La2O3 NPs treatment inhibited the translocation of nuclear factor erythroid 2-related factor 2 (Nrf-2) from the cytoplasm into the nucleus as well as the expression of downstream genes NAD(P)H quinone oxidoreductase1 (NQO1), hemeoxygenase 1 (HO-1) and (glutathione peroxidase) GSH-Px, thus abrogating Nrf-2-mediated defense mechanisms against oxidative stress. Conclusions: The results of this study demonstrated that La2O3 NPs improved the spermatogenesis defects in mice. La2O3 NPs inhibited Nrf-2/ARE signaling pathway that resulted in apoptosis in the mice testes.


Assuntos
Elementos de Resposta Antioxidante/genética , Lantânio/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Nanopartículas/toxicidade , Óxidos/toxicidade , Reprodução/efeitos dos fármacos , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Inflamação/patologia , Lantânio/sangue , Masculino , Camundongos , Nanopartículas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Óxidos/sangue , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testículo/ultraestrutura , Testosterona/biossíntese , Testosterona/metabolismo
16.
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
17.
Andrologia ; 52(9): e13712, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32578263

RESUMO

We performed this systematic review to evaluate the possibility of an impact of SARS-CoV-2 infection on male fertility. SARS-CoV-2 enters the cells with the help of ACE2; therefore, testicular expression of ACE2 was analysed from transcriptome sequencing studies and our unpublished data. Literature suggested that SARS-CoV-1 (2002-2004 SARS) had a significant adverse impact on testicular architecture, suggesting a high possibility of the impact of SARS-CoV-2 as well. Out of two studies on semen samples from COVID-19 affected patients, one reported the presence of SARS-CoV-2 in the semen samples while the other denied it, raising conflict about its presence in the semen samples and the possibility of sexual transmission. Our transcriptome sequencing studies on rat testicular germ cells showed ACE expression in rat testicular germ cells. We also found ACE2 expression in transcriptome sequencing data for human spermatozoa, corroborating its presence in the testicular germ cells. Transcriptome sequencing data from literature search revealed ACE2 expression in the germ, Sertoli and Leydig cells. The presence of ACE2 on almost all testicular cells and the report of a significant impact of previous SARS coronavirus on testes suggest that SARS-CoV-2 is highly likely to affect testicular tissue, semen parameters and male fertility.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/complicações , Infertilidade Masculina/virologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/complicações , Testículo/metabolismo , Animais , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Perfilação da Expressão Gênica , Humanos , Infertilidade Masculina/patologia , Masculino , Modelos Animais , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Ratos , Sêmen/virologia , Espermatozoides/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Testículo/patologia
18.
PLoS Genet ; 16(6): e1008756, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32520939

RESUMO

Paternal cigarette smoke (CS) exposure is associated with increased risk of behavioral disorders and cancer in offspring, but the mechanism has not been identified. Here we use mouse models to investigate mechanisms and impacts of paternal CS exposure. We demonstrate that CS exposure induces sperm DNAme changes that are partially corrected within 28 days of removal from CS exposure. Additionally, paternal smoking is associated with changes in prefrontal cortex DNAme and gene expression patterns in offspring. Remarkably, the epigenetic and transcriptional effects of CS exposure that we observed in wild type mice are partially recapitulated in Nrf2-/- mice and their offspring, independent of smoking status. Nrf2 is a central regulator of antioxidant gene transcription, and mice lacking Nrf2 consequently display elevated oxidative stress, suggesting that oxidative stress may underlie CS-induced heritable epigenetic changes. Importantly, paternal sperm DNAme changes do not overlap with DNAme changes measured in offspring prefrontal cortex, indicating that the observed DNAme changes in sperm are not directly inherited. Additionally, the changes in sperm DNAme associated with CS exposure were not observed in sperm of unexposed offspring, suggesting the effects are likely not maintained across multiple generations.


Assuntos
Epigênese Genética , Fator 2 Relacionado a NF-E2/genética , Exposição Paterna , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Metilação de DNA , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/metabolismo , Espermatozoides/metabolismo
19.
Sci Rep ; 10(1): 8856, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483153

RESUMO

Extracellular vesicles (EVs) derived from different parts of the male reproductive tract can be internalized by human spermatozoa affecting their maturation and regulating their functions. Here we demonstrate that EVs derived from the female tract can be uptaken by sperm and affect their competence. Primary endometrial cells release EVs with a diameter between 50 and 350 nm and bear the standard vesicle and exosome marker proteins CD63, CD9, TSG101 and ALIX. The uptake of dye-labelled endometrial cell-derived EVs by spermatozoa, quantified as fluorescence intensity, was significantly higher when EVs were derived from cells in the proliferative phase. Vital, motile fluorescent sperm could be appreciated after a 48-hour co-incubation with endometrial cells previously labelled with the Vybrant™ DiO dye. EV internalization by sperm was blocked at 4 °C and by incubation with filipin, suggesting an energy-dependent process probably attributable to the lipid-raft domain mediated-endocytosis. Sperm ability to undergo capacitation and acrosome reaction was stimulated by endometrial cell-derived EVs as manifested by the increased protein tyrosine phosphorylation and evident reactivity when stimulated with a calcium ionophore. Based on these findings, EVs exchange may be suggested as an emerging way through which female reproductive tract cells can interact with the passing spermatozoa.


Assuntos
Vesículas Extracelulares/metabolismo , Espermatozoides/metabolismo , Ionóforos de Cálcio/farmacologia , Células Cultivadas , Temperatura Baixa , Proteínas de Ligação a DNA/metabolismo , Endocitose/efeitos dos fármacos , Endométrio/citologia , Endométrio/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Feminino , Filipina/farmacologia , Humanos , Masculino , Microdomínios da Membrana/metabolismo , Tamanho da Partícula , Fosforilação/efeitos dos fármacos , Tetraspanina 30/metabolismo , Fatores de Transcrição/metabolismo
20.
BMC Evol Biol ; 20(1): 67, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513118

RESUMO

BACKGROUND: Cysteine-RIch Secretory Proteins (CRISP) are expressed in the reproductive tract of mammalian males and are involved in fertilization and related processes. Due to their important role in sperm performance and sperm-egg interaction, these genes are likely to be exposed to strong selective pressures, including postcopulatory sexual selection and/or male-female coevolution. We here perform a comparative evolutionary analysis of Crisp genes in mammals. Currently, the nomenclature of CRISP genes is confusing, as a consequence of discrepancies between assignments of orthologs, particularly due to numbering of CRISP genes. This may generate problems when performing comparative evolutionary analyses of mammalian clades and species. To avoid such problems, we first carried out a study of possible orthologous relationships and putative origins of the known CRISP gene sequences. Furthermore, and with the aim to facilitate analyses, we here propose a different nomenclature for CRISP genes (EVAC1-4, "EVolutionarily-analyzed CRISP") to be used in an evolutionary context. RESULTS: We found differing selective pressures among Crisp genes. CRISP1/4 (EVAC1) and CRISP2 (EVAC2) orthologs are found across eutherian mammals and seem to be conserved in general, but show signs of positive selection in primate CRISP1/4 (EVAC1). Rodent Crisp1 (Evac3a) seems to evolve under a comparatively more relaxed constraint with positive selection on codon sites. Finally, murine Crisp3 (Evac4), which appears to be specific to the genus Mus, shows signs of possible positive selection. We further provide evidence for sexual selection on the sequence of one of these genes (Crisp1/4) that, unlike others, is thought to be exclusively expressed in male reproductive tissues. CONCLUSIONS: We found differing selective pressures among CRISP genes and sexual selection as a contributing factor in CRISP1/4 gene sequence evolution. Our evolutionary analysis of this unique set of genes contributes to a better understanding of Crisp function in particular and the influence of sexual selection on reproductive mechanisms in general.


Assuntos
Evolução Molecular , Mamíferos/genética , Proteínas de Plasma Seminal/genética , Animais , Feminino , Masculino , Camundongos , Reprodução/genética , Espermatozoides/metabolismo
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