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1.
Chemistry ; 29(16): e202203807, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36594445

RESUMO

A one-step method for the conversion of nitroarenes into phenols under operationally simple, transition-metal-free conditions is described. This denitrative functionalization protocol provides a concise and economical alternative to conventional three-step synthetic sequences. Experimental and computational studies suggest that nitroarenes may be substituted by an electron-catalysed radical-nucleophilic substitution (SRN 1) chain mechanism.

2.
Reprod Biol Endocrinol ; 19(1): 141, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517901

RESUMO

Caudal Type Homeobox 2 (CDX2) is a key regulator of trophectoderm formation and maintenance in preimplantation embryos. We previously demonstrated that supplementation of exogenous follistatin, during in vitro culture of bovine IVF embryos, upregulates CDX2 expression, possibly, via alteration of the methylation status of CDX2 gene. Here, we further investigated the effects of exogenous follistatin supplementation on developmental competence and CDX2 methylation in bovine somatic cell nuclear transfer (SCNT) embryos. SCNT embryos were cultured with or without follistatin for 72h, then transferred into follistatin free media until d7 when blastocysts were collected and subjected to CDX2 gene expression and DNA methylation analysis for CDX2 regulatory regions by bisulfite sequencing. Follistatin supplementation significantly increased both blastocyst development as well as blastocyst CDX2 mRNA expression on d7. Three different CpG rich fragments within the CDX2 regulatory elements; proximal promoter (fragment P1, -1644 to -1180; P2, -305 to +126) and intron 1 (fragment I, + 3030 to + 3710) were identified and selected for bisulfite sequencing analysis. This analysis showed that follistatin treatment induced differential methylation (DM) at specific CpG sites within the analyzed fragments. Follistatin treatment elicited hypomethylation at six CpG sites at positions -1374, -279, -163, -23, +122 and +3558 and hypermethylation at two CpG sites at positions -243 and +20 in promoter region and first intron of CDX2 gene. Motif analysis using MatInspector revealed that differentially methylated CpG sites are putative binding sites for key transcription factors (TFs) known to regulate Cdx2 expression in mouse embryos and embryonic stem cells including OCT1, AP2F, KLF and P53, or TFs that have indirect link to CDX2 regulation including HAND and NRSF. Collectively, results of the present study together with our previous findings in IVF embryos support the hypothesis that alteration of CDX2 methylation is one of the epigenetic mechanisms by which follistatin may regulates CDX2 expression in preimplantation bovine embryos.


Assuntos
Blastocisto/efeitos dos fármacos , Fator de Transcrição CDX2/genética , Metilação de DNA/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Folistatina/farmacologia , Animais , Blastocisto/fisiologia , Fator de Transcrição CDX2/efeitos dos fármacos , Bovinos/embriologia , Células Cultivadas , Clonagem de Organismos/veterinária , Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/genética , Metilação de DNA/genética , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/veterinária , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Feminino , Fertilização in vitro/veterinária , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/métodos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Transferência Nuclear/veterinária
3.
Int J Group Psychother ; 71(3): 441-470, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38449226

RESUMO

Law enforcement violence has emerged as a leading public health concern, and law enforcement officers are themselves at greater risk for a range of psychiatric disorders. Drawing on the significant empirical support for mentalization-based treatment (MBT), this paper explores the use of MBT as a transdiagnostic psychotherapy for law enforcement professionals. By helping patients to mentalize-that is, to "read," access, and reflect on mental states in oneself and other people-MBT could be useful as a dual-focus treatment, able to simultaneously impact psychiatric illness among law enforcement officers while also indirectly impacting the problem of law enforcement violence in the broader society. The core psychotherapeutic principles of MBT are reviewed, along with common vulnerabilities in mentalizing likely to arise for law enforcement professionals in the context of high emotional and interpersonal intensity. The authors outline a novel application of MBT which has implications for psychiatric treatment as well as police training: the single-session psychoeducation and psychotherapy group, where law enforcement officers practice both self-reflection and empathy in situations of relational conflict. Utilizing group process from a residential treatment program for first responders with mental health and substance use disorders, a case example is offered to illustrate this intervention.

4.
Mol Reprod Dev ; 87(9): 998-1008, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32776625

RESUMO

CDX2 plays a crucial role in the formation and maintenance of the trophectoderm epithelium in preimplantation embryos. Follistatin supplementation during the first 72 hr of in vitro culture triggers a significant increase in blastocyst rates, CDX2 expression, and trophectoderm cell numbers. However, the underlying epigenetic mechanisms by which follistatin upregulates CDX2 expression are not known. Here, we investigated whether stimulatory effects of follistatin are linked to alterations in DNA methylation within key regulatory regions of the CDX2 gene. In vitro-fertilized (IVF) zygotes were cultured with or without 10 ng/ml of recombinant human follistatin for 72 hr, then cultured without follistatin until Day 7. The bisulfite-sequencing analysis revealed differential methylation (DM) at specific CpG sites within the CDX2 promoter and intron 1 following follistatin treatment. These DM CpG sites include five hypomethylated sites at positions -1384, -1283, -297, -163, and -23, and four hypermethylated sites at positions -1501, -250, -243, and +20 in the promoter region. There were five hypomethylated sites at positions +3060, +3105, +3219, +3270, and +3545 in intron 1. Analysis of transcription factor binding sites using MatInspector combined with a literature search revealed a potential association between differentially methylated CpG sites and putative binding sites for key transcription factors involved in regulating CDX2 expression. The hypomethylated sites are putative binding sites for FXR, STAF, OCT1, KLF, AP2 family, and P53 protein, whereas the hypermethylated sites are putative binding sites for NRSF. Collectively, our results suggest that follistatin may increase CDX2 expression in early bovine embryos, at least in part, by modulating DNA methylation at key regulatory regions.


Assuntos
Blastocisto/efeitos dos fármacos , Fator de Transcrição CDX2/genética , Bovinos/embriologia , Metilação de DNA/efeitos dos fármacos , Folistatina/farmacologia , Animais , Blastocisto/metabolismo , Fator de Transcrição CDX2/metabolismo , Bovinos/genética , Células Cultivadas , Técnicas de Cultura Embrionária , Embrião de Mamíferos , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Fertilização in vitro/veterinária , Regulação da Expressão Gênica no Desenvolvimento
5.
Biotechniques ; 68(3): 155-158, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31937114

RESUMO

We developed a simplified workflow of gDNA extraction from ejaculated bovine sperm using a low total number of sperm and a short time frame that yields high-quality DNA suitable for downstream methylation and genome analyses. These techniques have broad implications in human biomedical sciences and agriculture, including clinical diagnoses of infertility, the identification of single-nucleotide polymorphisms and aberrant methylation patterns that can impact fertility, lower embryo development and contribute to heritable disease. The methods described here provide a reliable, simplistic approach for analyzing both the genomic and epigenomic status of whole sperm ejaculates that can be adapted for laboratory diagnostics, clinical reproductive practice and basic research.


Assuntos
Metilação de DNA/genética , DNA/análise , Oligospermia/genética , Análise de Sequência de DNA/métodos , Espermatozoides/química , Animais , Bovinos , DNA/genética , Genoma/genética , Masculino , Oligospermia/veterinária , Reação em Cadeia da Polimerase , Análise do Sêmen , Análise de Sequência de DNA/veterinária
6.
Biol Reprod ; 102(4): 795-805, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31965149

RESUMO

Characterization of the molecular factors regulating early embryonic development and their functional mechanisms is critical for understanding the causes of early pregnancy loss in monotocous species (cattle, human). We previously characterized a stage specific functional role of follistatin, a TGF-beta superfamily binding protein, in promoting early embryonic development in cattle. The mechanism by which follistatin mediates this embryotropic effect is not precisely known as follistatin actions in cattle embryos are independent of its classically known activin inhibition activity. Apart from activin, follistatin is known to bind and modulate the activity of the bone morphogenetic proteins (BMPs), which signal through SMAD1/5 pathway and regulate several aspects of early embryogenesis in other mammalian species. Present study was designed to characterize the activity and functional requirement of BMP signaling during bovine early embryonic development and to investigate if follistatin involves BMP signaling for its stage specific embryotropic actions. Immunostaining and western blot analysis demonstrated that SMAD1/5 signaling is activated after embryonic genome activation in bovine embryos. However, days 1-3 follistatin treatment reduced the abundance of phosphorylated SMAD1/5 in cultured embryos. Inhibition of active SMAD1/5 signaling (8-16 cell to blastocyst) using pharmacological inhibitors and/or lentiviral-mediated inhibitory SMAD6 overexpression showed that SMAD1/5 signaling is required for blastocyst production, first cell lineage determination as well as mRNA and protein regulation of TE (CDX2) cell markers. SMAD1/5 signaling was also found to be essential for embryotropic actions of follistatin during days 4-7 but not days 1-3 of embryo development suggesting a role for follistatin in regulation of SMAD1/5 signaling in bovine embryos.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Folistatina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Bovinos , Diferenciação Celular/efeitos dos fármacos , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Gravidez , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo
7.
BMC Dev Biol ; 19(1): 23, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31787077

RESUMO

BACKGROUND: Epigenetic regulation of oocyte-specific maternal factors is essential for oocyte and early embryonic development. KPNA7 is an oocyte-specific maternal factor, which controls transportation of nuclear proteins important for early embryonic development. To elucidate the epigenetic mechanisms involved in the controlled expression of KPNA7, both DNA methylation associated transcriptional silencing and microRNA (miRNA)-mediated mRNA degradation of KPNA7 were examined. RESULTS: Comparison of DNA methylation profiles at the proximal promoter of KPNA7 gene between oocyte and 6 different somatic tissues identified 3 oocyte-specific differentially methylated CpG sites. Expression of KPNA7 mRNA was reintroduced in bovine kidney-derived CCL2 cells after treatment with the methylation inhibitor, 5-aza-2'-deoxycytidine (5-Aza-CdR). Analysis of the promoter region of KPNA7 gene in CCL2 cells treated with 5-Aza-CdR showed a lighter methylation rate in all the CpG sites. Bioinformatic analysis predicted 4 miRNA-1296 binding sites in the coding region of KPNA7 mRNA. Ectopic co-expression of miRNA-1296 and KPNA7 in HEK293 cells led to reduced expression of KPNA7 protein. Quantitative real time PCR (RT-qPCR) analysis revealed that miRNA-1296 is expressed in oocytes and early stage embryos, and the expression reaches a peak level in 8-cell stage embryos, coincident with the time of embryonic genome activation and the start of declining of KPNA7 expression. CONCLUSIONS: These results suggest that DNA methylation may account for oocyte-specific expression of KPNA7, and miRNA-1296 targeting the coding region of KPNA7 is a potential mechanism for KPNA7 transcript degradation during the maternal-to-zygotic transition.


Assuntos
Metilação de DNA , MicroRNAs/genética , Oócitos/crescimento & desenvolvimento , alfa Carioferinas/genética , Animais , Sítios de Ligação , Bovinos , Linhagem Celular , Desenvolvimento Embrionário , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Humanos , Oócitos/química , Especificidade de Órgãos , Regiões Promotoras Genéticas , Estabilidade de RNA , RNA Mensageiro/química , alfa Carioferinas/química
8.
Toxicol Sci ; 168(2): 610-619, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30629257

RESUMO

We previously demonstrated that periconception maternal administration (2 mg/kg body weight each) of cadmium chloride (CdCl2) plus methylmercury (II) chloride (CH3HgCl) impaired glucose homeostasis and increased body weights and abdominal adipose tissue weight of male offspring in the F1 generation. However, transgenerational effects of this exposure have not been studied. Therefore, the effects of periconception Cd+Hg administration on indices of chronic diseases at adulthood in F2-F4 generations were examined. Male and female progeny of Cd+Hg periconceptionally treated females, and offspring of vehicle control females were bred with naïve CD1 mice to obtain F2 offspring, with additional crosses as above to the F4 generation (F1-F4 animals were not administered Cd+Hg). Birth weights and litter size were similar in all generations. Indices of impaired glucose homeostasis were observed in matrilineally descended F2 male offspring, including reduced glucose tolerance, along with increased basal phosphorylation of insulin receptor substrate 1 (IRS1) at serine 307 suggesting altered insulin signaling. Reduced glucose tolerance was also seen in F4 males. Increased body weight and/or abdominal adiposity were observed through the F4 generation in males descended matrilineally from the treated female progenitors. Patrilineally derived F2 females displayed reduced glucose tolerance. Females (F2) patrilineally and matrilineally derived displayed significant kidney enlargement. Periconception administration of cadmium and mercury caused persistent transgenerational effects in offspring through the F4 generation in the absence of continued toxicant exposure, with persistent transgenerational effects inherited specifically through the matrilineal germline.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Metais Pesados/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Tecido Adiposo/embriologia , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Cloreto de Cádmio/toxicidade , Feminino , Masculino , Compostos de Metilmercúrio/toxicidade , Camundongos Endogâmicos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fatores Sexuais
9.
Biotechniques ; 65(5): 281-283, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30394131

RESUMO

CRISPR technologies used for mammalian embryology have wide implications from basic research to applications in agriculture and biomedicine. Confirmation of successful gene editing following CRISPR/Cas9 delivery is often limited to either protein expression or sequencing analyses of embryos but not both, due to technical challenges. Herein we report an integrative approach for evaluating both protein expression and genotype of single embryos from fixed bovine embryos previously subjected to CRISPR/Cas9 microinjection. The techniques described facilitate investigation of functional genomics in bovine embryos compatible with gene editing in livestock after zygotic CRISPR microinjection. These methods avoid traditional avenues that necessitate the use of gene-edited cell lines followed by nuclear transfer that hinder efficiency, limit physiological relevance and contribute to technical challenges.


Assuntos
Sistemas CRISPR-Cas , Bovinos/embriologia , Bovinos/genética , Edição de Genes/métodos , Animais , Sequência de Bases , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA/análise , DNA/genética , Embrião de Mamíferos/química , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/ultraestrutura , Imuno-Histoquímica/métodos , Imagem Óptica/métodos , Análise de Sequência de DNA/métodos , Fixação de Tecidos/métodos
10.
Reprod Biol ; 18(3): 267-273, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30196810

RESUMO

Using sex-sorted semen to produce offspring of desired sex is associated with reduced developmental competence in vitro and lower fertility rates in vivo. The objectives of the present study were to investigate the effects of exogenous follistatin supplementation on the developmental competence of bovine embryos produced with sex-sorted semen and possible link between TGF-ß regulated pathways and embryotrophic actions of follistatin. Effects of follistatin on expression of cell lineage markers (CDX2 and Nanog) and downstream targets of SMAD signaling (CTGF, ID1, ID2 and ID3) and AKT phosphorylation were investigated. Follistatin was supplemented during the initial 72 h of embryo culture. Exogenous follistatin restored the in vitro developmental competence of embryos produced with sex-sorted semen to the levels of control embryos produced with unsorted semen, and comparable results were obtained using sorted semen from three different bulls. The mRNA abundance for SMAD signaling downstream target genes, CTGF (SMAD 2/3 pathway) and ID2 (SMAD 1/5 pathway), was lower in blastocysts produced using sex-sorted versus unsorted semen, but mRNA levels for CDX2, NANOG, ID1 and ID3 were similar in both groups. Follistatin supplementation restored CTGF and ID2 mRNA in blastocysts produced using sex-sorted semen to levels of control embryos. Moreover, levels of phosphorylated (p)AKT (Ser-473 and Thr-308) were similar in embryos derived from sex-sorted and unsorted semen, but follistatin treatment increased pAKT levels in both groups. Taken together, results demonstrated that follistatin improves in vitro development of embryos produced with sex-sorted semen and such effects are associated with enhanced indices of SMAD signaling.


Assuntos
Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro/veterinária , Folistatina/farmacologia , Sêmen , Animais , Bovinos , Desenvolvimento Embrionário/fisiologia , Feminino , Masculino , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo
11.
J Mol Med (Berl) ; 96(10): 1107-1118, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30105447

RESUMO

Aberrant growth of blood vessels in the choroid layer of the eye, termed choroidal neovascularization (CNV), is the pathological hallmark of exudative age-related macular degeneration (AMD), causing irreversible blindness among the elderly. Co-localization of proangiogenic factors and hypoxia inducible factors (HIF) in neovascular membranes from AMD eyes suggests the role of hypoxia in pathogenesis of CNV. In order to utilize hypoxic conditions in RPE for therapeutic purposes, we developed an optimized hypoxia regulated, RPE cell-specific gene therapy to inhibit choroidal neovascularization. An adeno-associated virus (AAV2) vector comprising a RPE-specific promoter and HIF-1 response elements (HRE) was designed to regulate production of human endostatin (a powerful angiostatic protein) in RPE. The vector was tested in a mouse model of laser-induced CNV using subretinal delivery. Spectral domain optical coherence tomography (SD-OCT) images from live mice and confocal images from lectin stained RPE flat mount sections demonstrated reduction in CNV areas by 80% compared to untreated eyes. Quantitative real-time polymerase chain reaction (qPCR) confirmed exogenous endostatin mRNA expression from the regulated vector that was significantly elevated 3, 7, and 14 days following laser treatment, but its expression was completely shut off after 45 days. Thus, RPE-specific, hypoxia-regulated delivery of anti-angiogenic proteins could be a valuable therapeutic approach to treat neovascular AMD at the time and in the ocular space where it arises. KEY POINTS: An optimized gene therapy vector targeting hypoxia and tissue-specific expression has been designed. The inhibitory role of gene therapy vector was tested in a mouse model of laser-induced CNV. An 80% reduction in choroidal neovascularization was achieved by the optimized vector. The expression of endostatin was limited to retinal pigment epithelium and regulated by hypoxia.


Assuntos
Neovascularização de Coroide/terapia , Terapia Genética , Hipóxia , Animais , Dependovirus , Endostatinas/genética , Endostatinas/metabolismo , Vetores Genéticos , Camundongos Endogâmicos C57BL , Parvovirinae/genética , Epitélio Pigmentado da Retina/metabolismo
12.
Sci Rep ; 8(1): 7753, 2018 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-29773834

RESUMO

POU5F1 is a transcription factor and master regulator of cell pluripotency with indispensable roles in early embryo development and cell lineage specification. The role of embryonic POU5F1 in blastocyst formation and cell lineage specification differs between mammalian species but remains completely unknown in cattle. The CRISPR/Cas9 system was utilized for targeted disruption of the POU5F1 gene by direct injection into zygotes. Disruption of the bovine POU5F1 locus prevented blastocyst formation and was associated with embryonic arrest at the morula stage. POU5F1 knockout morulas developed at a similar rate as control embryos and presented a similar number of blastomeres by day 5 of development. Initiation of SOX2 expression by day 5 of development was not affected by lack of POU5F1. On the other hand, CDX2 expression was aberrant in embryos lacking POU5F1. Notably, the phenotype observed in bovine POU5F1 knockout embryos reveals conserved functions associated with loss of human embryonic POU5F1 that differ from Pou5f1- null mice. The similarity observed in transcriptional regulation of early embryo development between cattle and humans combined with highly efficient gene editing techniques make the bovine a valuable model for human embryo biology with expanded applications in agriculture and assisted reproductive technologies.


Assuntos
Blastocisto/citologia , Linhagem da Célula , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Fator 3 de Transcrição de Octâmero/metabolismo , Animais , Blastocisto/metabolismo , Sistemas CRISPR-Cas , Bovinos , Embrião de Mamíferos/metabolismo , Feminino , Edição de Genes , Fator 3 de Transcrição de Octâmero/antagonistas & inibidores , Fator 3 de Transcrição de Octâmero/genética
13.
Reprod Biol Endocrinol ; 16(1): 1, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29310676

RESUMO

BACKGROUND: TGF-ß signaling pathways regulate several crucial processes in female reproduction. AKT is a non-SMAD signaling pathway regulated by TGF-ß ligands essential for oocyte maturation and early embryonic development in the mouse, but its regulatory role in bovine early embryonic development is not well established. Previously, we demonstrated a stimulatory role for follistatin (a binding protein for specific members of TGF-ß superfamily) in early bovine embryonic development. The objectives of the present studies were to determine the functional role of AKT signaling in bovine early embryonic development and embryotrophic actions of follistatin. METHODS: We used AKT inhibitors III and IV as pharmacological inhibitors of AKT signaling pathway during the first 72 h of in vitro embryo culture. Effects of AKT inhibition on early embryonic development and AKT phosphorylation were investigated in the presence or absence of exogenous follistatin. RESULTS: Pharmacological inhibition of AKT signaling resulted in a significant reduction in early embryo cleavage, and development to the 8- to 16-cell and blastocyst stages (d7). Treatment with exogenous follistatin increased AKT phosphorylation and rescued the inhibitory effect of AKT inhibitors III and IV on AKT phosphorylation and early embryonic development. CONCLUSIONS: Collectively, results suggest a potential requirement of AKT for bovine early embryonic development, and suggest a potential role for follistatin in regulation of AKT signaling in early bovine embryos.


Assuntos
Bovinos/embriologia , Desenvolvimento Embrionário , Folistatina/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Animais , Bovinos/metabolismo , Feminino , Folistatina/metabolismo , Folistatina/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo
14.
Reprod Sci ; 25(5): 759-772, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28845753

RESUMO

Mammalian oocytes resume maturation when removed from follicles and cultured in vitro. During folliculogenesis, oocytes are bathed in follicular fluid (FF), which provides an important and specialized microenvironment for oocyte competence. Follistatin (FST) is one component of FF that may play a role in oocyte maturation and embryo development. This study was conducted to examine possible effects of FST on porcine oocyte competence and embryo development. Exogenous FST in oocyte maturation medium for 22 or 44 hours did not improve nuclear maturation and had no effect on good quality cumulus-oocyte complexes (COCs). However, FST improved blastocyst rates in embryos derived from oocytes with less than 2 layers of cumulus. Follistatin treatment of the poor quality COC group increased transcript levels for genes indicative of oocyte quality. Transcript levels were also altered for cumulus expansion-related genes in response to FST when measured during the germinal vesicle breakdown stage. Interestingly, high-quality oocytes remained at germinal vesicle stage much longer than low-quality oocytes, FST treatment induced temporary blockage of spontaneous meiotic resumption when added during culture of both good and poor quality COCs, and levels of cyclic guanosine monophosphate (cGMP) were higher in FST-treated versus untreated groups for both good and poor quality oocytes. In conclusion, FST treatment of porcine oocytes during in vitro maturation can rescue competency of poor quality oocytes to develop to blastocyst stage following in vitro fertilization. Beneficial effects of addition of FST to culture medium may be mediated by inhibiting degradation of cGMP and temporarily delaying nuclear maturation.


Assuntos
Blastocisto/efeitos dos fármacos , Células do Cúmulo/efeitos dos fármacos , GMP Cíclico/metabolismo , Desenvolvimento Embrionário , Folistatina/farmacologia , Meiose , Oócitos/efeitos dos fármacos , Animais , Blastocisto/fisiologia , Células Cultivadas , Células do Cúmulo/fisiologia , Oócitos/crescimento & desenvolvimento , Sus scrofa
15.
Mol Reprod Dev ; 85(2): 106-116, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29232016

RESUMO

Histone variant H3.3 is encoded by two distinct genes, H3F3A and H3F3B, that are closely associated with actively transcribed genes. H3.3 replacement is continuous and essential for maintaining correct chromatin structure during mouse oogenesis. Upon fertilization, H3.3 is incorporated to parental chromatin, and is required for blastocyst formation in mice. The H3.3 exchange process is facilitated by the chaperone HIRA, particularly during zygote development. We previously demonstrated that H3.3 is required for bovine early embryonic development; here, we explored the mechanisms of its functional requirement. H3F3A mRNA abundance is stable whereas H3F3B and HIRA mRNA are relatively dynamic during early embryonic development. H3F3B mRNA quantity is also considerably higher than H3F3A. Immunofluorescence analysis revealed an even distribution of H3.3 between paternal and maternal pronuclei in zygotes, and subsequent stage-specific localization of H3.3 in early bovine embryos. Knockdown of H3.3 by targeting both H3F3A and H3F3B dramatically decreased the expression of NANOG (a pluripotency marker) and CTGF (Connective tissue growth factor; a trophectoderm marker) in bovine blastocysts. Additionally, we noted that Histone H3 lysine 36 dimethylation and linker Histone H1 abundance is reduced in H3.3-deficient embryos, which was similar to effects following knockdown of CHD1 (Chromodomain helicase DNA-binding protein 1). By contrast, no difference was observed in the abundance of Histone H3 lysine 4 trimethylation, Histone H3 lysine 9 dimethylation, or Splicing factor 3 B1. Collectively, these results established that H3.3 is required for correct epigenetic modifications and H1 deposition, dysregulation of which likely mediate the poor development in H3.3-deficient embryos.


Assuntos
Blastocisto/metabolismo , Bovinos , Chaperonas de Histonas/genética , Chaperonas de Histonas/fisiologia , Histonas/genética , Animais , Bovinos/embriologia , Bovinos/genética , Linhagem da Célula/genética , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Masculino , Gravidez , Zigoto/metabolismo
16.
Sci Rep ; 7(1): 13783, 2017 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-29062096

RESUMO

The mammalian integumentary system plays important roles in body homeostasis, and dysfunction of melanogenesis or epidermal development may lead to a variety of skin diseases, including melanoma. Skin pigmentation in humans and coat color in fleece-producing animals are regulated by many genes. Among them, microphthalmia-associated transcription factor (MITF) and paired-box 3 (PAX3) are at the top of the cascade and regulate activities of many important melanogenic enzymes. Here, we report for the first time that cyclin-dependent kinase 5 (Cdk5) is an essential regulator of MITF and PAX3. Cdk5 knockdown in mice causes a lightened coat color, a polarized distribution of melanin and hyperproliferation of basal keratinocytes. Reduced expression of Keratin 10 (K10) resulting from Cdk5 knockdown may be responsible for an abnormal epidermal structure. In contrast, overexpression of Cdk5 in sheep (Ovis aries) only produces brown patches on a white background, with no other observable abnormalities. Collectively, our findings show that Cdk5 has an important functional role in the regulation of melanin production and transportation and in normal development of the integumentary system.


Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Epiderme/química , Melanócitos/citologia , Pigmentação da Pele/fisiologia , Animais , Células Cultivadas , Quinase 5 Dependente de Ciclina/genética , Regulação para Baixo , Epiderme/crescimento & desenvolvimento , Epiderme/metabolismo , Feminino , Masculino , Melanócitos/metabolismo , Camundongos , Camundongos Knockout , Ovinos , Transdução de Sinais
17.
Mech Dev ; 144(Pt B): 103-112, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28263788

RESUMO

Zinc finger (ZNF) transcription factors interact with DNA through zinc finger motifs and play important roles in a variety of cellular functions including cell growth, proliferation, development, apoptosis, and intracellular signal transduction. One-third of ZNF proteins in metazoans contain a highly conserved N-terminal motif known as the Krüppel-associated box (KRAB) domain, which acts as a potent, DNA-binding dependent transcriptional repression module. Analysis of RNA-Seq data generated from a bovine oocyte cDNA library identified a novel transcript, which encodes a KRAB-containing ZNF transcription factor (named ZNFO). Characterization of ZNFO mRNA expression revealed that it is exclusively expressed in bovine oocytes and early embryos. A GFP reporter assay demonstrated that ZNFO protein localizes specifically to the nucleus, supporting its role in transcriptional regulation. To test the role of ZNFO in early embryonic development, zygotes were generated by in vitro maturation and fertilization of oocytes, and injected with small interfering RNA (siRNA) designed to knockdown ZNFO. Cleavage rates were not affected by ZNFO siRNA injection. However, embryonic development to 8- to 16-cell stage and blastocyst stage was significantly reduced relative to the uninjected and negative control siRNA-injected embryos. Further, interaction of ZNFO with the highly conserved co-factor, KRAB-associated protein-1 (KAP1), was demonstrated, and evidence supporting transcriptional repression by ZNFO was demonstrated using a GAL4-luciferase reporter system. Results of described studies demonstrate that ZNFO is a maternally-derived oocyte-specific nuclear factor required for early embryonic development in cattle, presumably functioning by repressing transcription.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Oócitos/fisiologia , Proteínas Repressoras/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Clonagem Molecular , Desenvolvimento Embrionário , Expressão Gênica , Células HEK293 , Humanos , Transporte Proteico , Coelhos , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo , Dedos de Zinco
18.
PLoS One ; 12(1): e0170808, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28122009

RESUMO

Our previous studies demonstrated that maternal (oocyte derived) follistatin (FST) expression is positively associated with bovine oocyte competence and exogenous follistatin treatment during the pre-compaction period of development (d 1-3 post insemination) is stimulatory to bovine early embryogenesis in vitro [blastocyst rates and cell numbers/allocation to trophectoderm (TE)]. In the present study, bovine embryos were treated with exogenous follistatin during d 1-3, d 4-7 and d 1-7 post insemination to test the hypothesis that embryotropic effects of exogenous follistatin are specific to the pre-compaction period (d 1-3) of early embryogenesis. Follistatin treatment during d 4-7 (peri-/post-compaction period) of embryo culture increased proportion of embryos reaching blastocyst and expanded blastocyst stage and total cell numbers compared to controls, but blastocyst rates and total cell numbers were lower than observed following d 1-3 (pre-compaction) follistatin treatment. Follistatin supplementation during d 1-7 of embryo culture increased development to blastocyst and expanded blastocyst stages and blastocyst total cell numbers compared to d 1-3 and d 4-7 follistatin treatment and untreated controls. A similar increase in blastocyst CDX2 mRNA and protein (TE cell marker) was observed in response to d 1-3, d 4-7 and d 1-7 follistatin treatment. However, an elevation in blastocyst BMP4 protein (TE cell regulator) was observed in response to d 1-3 and d 1-7, but not d 4-7 (peri-/post-compaction) follistatin treatment. In summary, our study revealed the potential utility of follistatin treatment for increasing the success rate of in vitro embryo production in cattle. Such results also expand our understanding of the embryotropic actions of follistatin and demonstrate that follistatin actions on blastocyst development and cell allocation to the TE layer are not specific to the pre-compaction period.


Assuntos
Blastocisto/efeitos dos fármacos , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/efeitos dos fármacos , Folistatina/farmacologia , Oócitos/efeitos dos fármacos , Animais , Blastocisto/citologia , Bovinos , Técnicas de Cultura Embrionária/métodos , Feminino , Fertilização in vitro , Oócitos/citologia
19.
Reproduction ; 153(4): 471-479, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28115581

RESUMO

We hypothesised that cocaine- and amphetamine-regulated transcript (CARTPT) would be differentially expressed in ewes with differing ovulation rates. Expression of mRNA for CARTPT, as well as LHCGR, FSHR, CYP19A1 and CYP17A1 was determined in antral follicles ≥1 mm in diameter collected during the follicular phase in ewes heterozygous for the Booroola and Inverdale genes (I+B+; average ovulation rate 4) and ++ contemporaries (++; average ovulation rate 1.8). In ++ ewes (n = 6), CARTPT was expressed in small follicles (1 to <3 mm diameter), where 18.8 ± 2.5% follicles expressed CARTPT CART peptide was also detected in follicular fluid of some follicles of ++ ewes. In I+B+ ewes, 5/6 ewes did not have any follicles that expressed CARTPT, and no CART peptide was detected in any follicle examined. Expression pattern of CYP19A1 differed between I+B+ and ++ ewes with an increased percentage of small and medium follicles (3 to <4.5 mm diameter) but decreased percentage of large follicles (≥4.5 mm diameter) expressing CYP19A1 in the I+B+ ewes. Many of the large follicles from the I+B+ ewes appeared non-functional and expression of LHCGR, FSHR, CYP17A1 and CYP19A1 was less than that observed in ++ ewes. Expression of FSHR and CYP17A1 was not different between groups in small and medium follicles, but LHCGR expression was approximately double in I+B+ ewes compared to that in ++ ewes. Thus, ewes with high ovulation rates had a distinct pattern of expression of CARTPT mRNA and protein compared to ewes with normal ovulation rates, providing evidence for CART being important in the regulation of ovulation rate.


Assuntos
Líquido Folicular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Folículo Ovariano/metabolismo , Ovulação/fisiologia , Animais , Aromatase/genética , Aromatase/metabolismo , Estradiol/metabolismo , Feminino , Proteínas do Tecido Nervoso/genética , Folículo Ovariano/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Ovinos , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo
20.
Environ Health Perspect ; 125(4): 643-650, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27814245

RESUMO

BACKGROUND: Long-term exposure to the heavy metals cadmium (Cd) and mercury (Hg) is known to increase the risk of chronic diseases. However, to our knowledge, exposure to Cd and Hg beginning at the periconception period has not been studied to date. OBJECTIVE: We examined the effect of Cd and Hg that were co-administered during early development on indices of chronic diseases in adult male mice. METHODS: Adult female CD1 mice were subcutaneously administered a combination of cadmium chloride (CdCl2) and methylmercury (II) chloride (CH3HgCl) (0, 0.125, 0.5, or 2.0 mg/kg body weight each) 4 days before and 4 days after conception (8 days total). Indices of anxiety-like behavior, glucose homeostasis, endocrine and molecular markers of insulin resistance, and organ weights were examined in adult male offspring. RESULTS: Increased anxiety-like behavior, impaired glucose homeostasis, and higher body weight and abdominal adipose tissue weight were observed in male offspring of treated females compared with controls. Significantly increased serum leptin and insulin concentrations and impaired insulin tolerance in the male offspring of dams treated with 2.0 mg/kg body weight of Cd and Hg suggested insulin resistance. Altered mRNA abundance for genes associated with glucose and lipid homeostasis (GLUT4, IRS1, FASN, ACACA, FATP2, CD36, and G6PC) in liver and abdominal adipose tissues as well as increased IRS1 phosphorylation in liver (Ser 307) provided further evidence of insulin resistance. CONCLUSIONS: Results suggest that the co-administration of Cd and Hg to female mice during the early development of their offspring (the periconception period) was associated with anxiety-like behavior, altered glucose metabolism, and insulin resistance in male offspring at adulthood.


Assuntos
Cádmio/toxicidade , Substâncias Perigosas/toxicidade , Mercúrio/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Doença Crônica , Feminino , Glucose/metabolismo , Homeostase , Resistência à Insulina , Masculino , Camundongos , Sobrepeso , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Testes de Toxicidade
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