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1.
Front Comput Neurosci ; 18: 1393122, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962654

RESUMO

Epilepsy is a common chronic brain disorder. Detecting epilepsy by observing electroencephalography (EEG) is the main method neurologists use, but this method is time-consuming. EEG signals are non-stationary, nonlinear, and often highly noisy, so it remains challenging to recognize epileptic EEG signals more accurately and automatically. This paper proposes a novel classification system of epileptic EEG signals for single-channel EEG based on the attention network that integrates time-frequency and nonlinear dynamic features. The proposed system has three novel modules. The first module constructs the Hilbert spectrum (HS) with high time-frequency resolution into a two-channel parallel convolutional network. The time-frequency features are fully extracted by complementing the high-dimensional features of the two branches. The second module constructs a grayscale recurrence plot (GRP) that contains more nonlinear dynamic features than traditional RP, fed into the residual-connected convolution module for effective learning of nonlinear dynamic features. The third module is the feature fusion module based on a self-attention mechanism to assign optimal weights to different types of features and further enhance the information extraction capability of the system. Therefore, the system is named HG-SANet. The results of several classification tasks on the Bonn EEG database and the Bern-Barcelona EEG database show that the HG-SANet can effectively capture the contribution degree of the extracted features from different domains, significantly enhance the expression ability of the model, and improve the accuracy of the recognition of epileptic EEG signals. The HG-SANet can improve the diagnosis and treatment efficiency of epilepsy and has broad application prospects in the fields of brain disease diagnosis.

2.
Cells ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38607035

RESUMO

Cell therapies derived from induced pluripotent stem cells (iPSCs) offer a promising avenue in the field of regenerative medicine due to iPSCs' expandability, immune compatibility, and pluripotent potential. An increasing number of preclinical and clinical trials have been carried out, exploring the application of iPSC-based therapies for challenging diseases, such as muscular dystrophies. The unique syncytial nature of skeletal muscle allows stem/progenitor cells to integrate, forming new myonuclei and restoring the expression of genes affected by myopathies. This characteristic makes genome-editing techniques especially attractive in these therapies. With genetic modification and iPSC lineage specification methodologies, immune-compatible healthy iPSC-derived muscle cells can be manufactured to reverse the progression of muscle diseases or facilitate tissue regeneration. Despite this exciting advancement, much of the development of iPSC-based therapies for muscle diseases and tissue regeneration is limited to academic settings, with no successful clinical translation reported. The unknown differentiation process in vivo, potential tumorigenicity, and epigenetic abnormality of transplanted cells are preventing their clinical application. In this review, we give an overview on preclinical development of iPSC-derived myogenic cell transplantation therapies including processes related to iPSC-derived myogenic cells such as differentiation, scaling-up, delivery, and cGMP compliance. And we discuss the potential challenges of each step of clinical translation. Additionally, preclinical model systems for testing myogenic cells intended for clinical applications are described.


Assuntos
Células-Tronco Pluripotentes Induzidas , Distrofias Musculares , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Músculo Esquelético/fisiologia , Distrofias Musculares/metabolismo , Terapia Baseada em Transplante de Células e Tecidos , Diferenciação Celular
3.
Cell Stem Cell ; 29(4): 610-619.e5, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35395188

RESUMO

Human pluripotent stem cell (hPSC)-derived myogenic progenitor cell (MPC) transplantation is a promising therapeutic approach for a variety of degenerative muscle disorders. Here, using an MPC-specific fluorescent reporter system (PAX7::GFP), we demonstrate that hPSC-derived MPCs can contribute to the regeneration of myofibers in mice following local injury and in mice deficient of dystrophin (mdx). We also demonstrate that a subset of PAX7::GFP MPCs engraft within the basal lamina of regenerated myofibers, adopt a quiescent state, and contribute to regeneration upon reinjury and in mdx mouse models. This subset of PAX7::GFP MPCs undergo a maturation process and remodel their molecular characteristics to resemble those of late-stage fetal MPCs/adult satellite cells following in vivo engraftment. These in-vivo-matured PAX7::GFP MPCs retain a cell-autonomous ability to regenerate and can repopulate in the niche of secondary recipient mice, providing a proof of principle for future hPSC-based cell therapy for muscle disorders.


Assuntos
Células-Tronco Pluripotentes , Células Satélites de Músculo Esquelético , Animais , Diferenciação Celular , Distrofina , Humanos , Camundongos , Camundongos Endogâmicos mdx , Desenvolvimento Muscular , Músculo Esquelético , Mioblastos , Transplante de Células-Tronco
4.
Front Psychol ; 13: 1075624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698559

RESUMO

Speech emotion recognition (SER) is the key to human-computer emotion interaction. However, the nonlinear characteristics of speech emotion are variable, complex, and subtly changing. Therefore, accurate recognition of emotions from speech remains a challenge. Empirical mode decomposition (EMD), as an effective decomposition method for nonlinear non-stationary signals, has been successfully used to analyze emotional speech signals. However, the mode mixing problem of EMD affects the performance of EMD-based methods for SER. Various improved methods for EMD have been proposed to alleviate the mode mixing problem. These improved methods still suffer from the problems of mode mixing, residual noise, and long computation time, and their main parameters cannot be set adaptively. To overcome these problems, we propose a novel SER framework, named IMEMD-CRNN, based on the combination of an improved version of the masking signal-based EMD (IMEMD) and convolutional recurrent neural network (CRNN). First, IMEMD is proposed to decompose speech. IMEMD is a novel disturbance-assisted EMD method and can determine the parameters of masking signals to the nature of signals. Second, we extract the 43-dimensional time-frequency features that can characterize the emotion from the intrinsic mode functions (IMFs) obtained by IMEMD. Finally, we input these features into a CRNN network to recognize emotions. In the CRNN, 2D convolutional neural networks (CNN) layers are used to capture nonlinear local temporal and frequency information of the emotional speech. Bidirectional gated recurrent units (BiGRU) layers are used to learn the temporal context information further. Experiments on the publicly available TESS dataset and Emo-DB dataset demonstrate the effectiveness of our proposed IMEMD-CRNN framework. The TESS dataset consists of 2,800 utterances containing seven emotions recorded by two native English speakers. The Emo-DB dataset consists of 535 utterances containing seven emotions recorded by ten native German speakers. The proposed IMEMD-CRNN framework achieves a state-of-the-art overall accuracy of 100% for the TESS dataset over seven emotions and 93.54% for the Emo-DB dataset over seven emotions. The IMEMD alleviates the mode mixing and obtains IMFs with less noise and more physical meaning with significantly improved efficiency. Our IMEMD-CRNN framework significantly improves the performance of emotion recognition.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34501969

RESUMO

Environment around conception can influence the developmental programme with lasting effects on gestational and postnatal phenotype and with consequences for adult health and disease risk. Peri-conception exposure comprises a crucial part of the 'Developmental Origins of Health and Disease' (DOHaD) concept. In this review, we consider the effects of maternal undernutrition experienced during the peri-conception period in select human models and in a mouse experimental model of protein restriction. Human datasets indicate that macronutrient deprivation around conception affect the epigenome, with enduring effects on cardiometabolic and neurological health. The mouse model, comprising maternal low protein diet exclusively during the peri-conception period, has revealed a stepwise progression in altered developmental programming following induction through maternal metabolite deficiency. This progression includes differential effects in extra-embryonic and embryonic cell lineages and tissues, leading to maladaptation in the growth trajectory and increased chronic disease comorbidities. The timeline embraces an array of mechanisms across nutrient sensing and signalling, cellular, metabolic, epigenetic and physiological processes with a coordinating role for mTORC1 signalling proposed. Early embryos appear active participants in environmental sensing to optimise the developmental programme for survival but with the trade-off of later disease. Similar adverse health outcomes may derive from other peri-conception environmental experiences, including maternal overnutrition, micronutrient availability, pollutant exposure and assisted reproductive treatments (ART) and support the need for preconception health before pregnancy.


Assuntos
Fertilização , Hipernutrição , Animais , Exposição Ambiental/efeitos adversos , Epigenômica , Feminino , Camundongos , Gravidez , Reprodução
6.
FASEB J ; 35(2): e21276, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33423297

RESUMO

Mitochondrial derangement is an important contributor to the pathophysiology of muscular dystrophies and may be among the earliest cellular deficits. We have previously shown that disruption of Mss51, a mammalian skeletal muscle protein that localizes to the mitochondria, results in enhanced muscle oxygen consumption rate, increased endurance capacity, and improved limb muscle strength in mice with wildtype background. Here, we investigate whether Mss51 deletion in the mdx murine model of Duchenne muscular dystrophy (mdx-Mss51 KO) counteracts the muscle pathology and mitochondrial irregularities observed in mdx mice. We found that mdx-Mss51 KO mice had increased myofiber oxygen consumption rates and an amelioration of muscle histopathology compared to mdx counterparts. This corresponded with greater treadmill endurance and less percent fatigue in muscle physiology, but no improvement in forelimb grip strength or limb muscle force production. These findings suggest that although Mss51 deletion ameliorates the skeletal muscle mitochondrial respiration defects in mdx and improves fatigue resistance in vivo, the lack of improvement in force production suggests that this target alone may be insufficient for a therapeutic effect.


Assuntos
Deleção de Genes , Proteínas Mitocondriais/genética , Força Muscular , Distrofia Muscular de Duchenne/genética , Fatores de Transcrição/genética , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/patologia , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Consumo de Oxigênio
7.
JCI Insight ; 5(11)2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32343677

RESUMO

Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy. In the present study, when human induced pluripotent stem cells (hiPSCs) were differentiated into myoblasts, the myoblasts derived from DMD patient hiPSCs (DMD hiPSC-derived myoblasts) exhibited an identifiable DMD-relevant phenotype: myogenic fusion deficiency. Based on this model, we developed a DMD hiPSC-derived myoblast screening platform employing a high-content imaging (BD Pathway 855) approach to generate parameters describing morphological as well as myogenic marker protein expression. Following treatment of the cells with 1524 compounds from the Johns Hopkins Clinical Compound Library, compounds that enhanced myogenic fusion of DMD hiPSC-derived myoblasts were identified. The final hits were ginsenoside Rd and fenofibrate. Transcriptional profiling revealed that ginsenoside Rd is functionally related to FLT3 signaling, while fenofibrate is linked to TGF-ß signaling. Preclinical tests in mdx mice showed that treatment with these 2 hit compounds can significantly ameliorate some of the skeletal muscle phenotypes caused by dystrophin deficiency, supporting their therapeutic potential. Further study revealed that fenofibrate could inhibit mitochondrion-induced apoptosis in DMD hiPSC-derived cardiomyocytes. We have developed a platform based on DMD hiPSC-derived myoblasts for drug screening and identified 2 promising small molecules with in vivo efficacy.


Assuntos
Fenofibrato/farmacologia , Ginsenosídeos/farmacologia , Células-Tronco Pluripotentes Induzidas , Distrofia Muscular de Duchenne , Mioblastos Esqueléticos , Animais , Avaliação Pré-Clínica de Medicamentos , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Camundongos , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Distrofia Muscular de Duchenne/tratamento farmacológico , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Mioblastos Esqueléticos/metabolismo , Mioblastos Esqueléticos/patologia
8.
Exp Neurol ; 323: 113086, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639376

RESUMO

Muscular dystrophies are a group of genetic muscle disorders that cause progressive muscle weakness and degeneration. Within this group, Duchenne muscular dystrophy (DMD) is the most common and one of the most severe. DMD is an X chromosome linked disease that occurs to 1 in 3500 to 1 in 5000 boys. The cause of DMD is a mutation in the dystrophin gene, whose encoded protein provides both structural support and cell signaling capabilities. So far, there are very limited therapeutic options available and there is no cure for this disease. In this review, we discuss the existing cell therapy research, especially stem cell-based, which utilize myoblasts, satellite cells, bone marrow cells, mesoangioblasts and CD133+ cells. Finally, we focus on human pluripotent stem cells (hPSCs) which hold great potential in treating DMD. hPSCs can be used for autologous transplantation after being specified to a myogenic lineage. Over the last few years, there has been a rapid development of isolation, as well as differentiation, techniques in order to achieve effective transplantation results of myogenic cells specified from hPSCs. In this review, we summarize the current methods of hPSCs myogenic commitment/differentiation, and describe the current status of hPSC-derived myogenic cell transplantation.


Assuntos
Distrofia Muscular de Duchenne/terapia , Mioblastos/citologia , Células-Tronco Pluripotentes/citologia , Transplante de Células-Tronco/métodos , Diferenciação Celular/fisiologia , Humanos , Mioblastos/transplante
9.
JCI Insight ; 4(20)2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31527314

RESUMO

Myostatin is a negative regulator of muscle growth and metabolism and its inhibition in mice improves insulin sensitivity, increases glucose uptake into skeletal muscle, and decreases total body fat. A recently described mammalian protein called MSS51 is significantly downregulated with myostatin inhibition. In vitro disruption of Mss51 results in increased levels of ATP, ß-oxidation, glycolysis, and oxidative phosphorylation. To determine the in vivo biological function of Mss51 in mice, we disrupted the Mss51 gene by CRISPR/Cas9 and found that Mss51-KO mice have normal muscle weights and fiber-type distribution but reduced fat pads. Myofibers isolated from Mss51-KO mice showed an increased oxygen consumption rate compared with WT controls, indicating an accelerated rate of skeletal muscle metabolism. The expression of genes related to oxidative phosphorylation and fatty acid ß-oxidation were enhanced in skeletal muscle of Mss51-KO mice compared with that of WT mice. We found that mice lacking Mss51 and challenged with a high-fat diet were resistant to diet-induced weight gain, had increased whole-body glucose turnover and glycolysis rate, and increased systemic insulin sensitivity and fatty acid ß-oxidation. These findings demonstrate that MSS51 modulates skeletal muscle mitochondrial respiration and regulates whole-body glucose and fatty acid metabolism, making it a potential target for obesity and diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Proteínas Mitocondriais/deficiência , Fibras Musculares Esqueléticas/metabolismo , Obesidade/metabolismo , Fatores de Transcrição/deficiência , Animais , Sistemas CRISPR-Cas/genética , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/genética , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Feminino , Humanos , Insulina , Resistência à Insulina/genética , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Fibras Musculares Esqueléticas/citologia , Obesidade/etiologia , Obesidade/genética , Oxirredução , Fosforilação Oxidativa , Consumo de Oxigênio , Fatores de Transcrição/genética , Aumento de Peso , Dedos de Zinco
10.
J Cell Sci ; 132(13)2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31138678

RESUMO

VGLL proteins are transcriptional co-factors that bind TEAD family transcription factors to regulate events ranging from wing development in fly, to muscle fibre composition and immune function in mice. Here, we characterise Vgll3 in skeletal muscle. We found that mouse Vgll3 was expressed at low levels in healthy muscle but that its levels increased during hypertrophy or regeneration; in humans, VGLL3 was highly expressed in tissues from patients with various muscle diseases, such as in dystrophic muscle and alveolar rhabdomyosarcoma. Interaction proteomics revealed that VGLL3 bound TEAD1, TEAD3 and TEAD4 in myoblasts and/or myotubes. However, there was no interaction with proteins from major regulatory systems such as the Hippo kinase cascade, unlike what is found for the TEAD co-factors YAP (encoded by YAP1) and TAZ (encoded by WWTR1). Vgll3 overexpression reduced the activity of the Hippo negative-feedback loop, affecting expression of muscle-regulating genes including Myf5, Pitx2 and Pitx3, and genes encoding certain Wnts and IGFBPs. VGLL3 mainly repressed gene expression, regulating similar genes to those regulated by YAP and TAZ. siRNA-mediated Vgll3 knockdown suppressed myoblast proliferation, whereas Vgll3 overexpression strongly promoted myogenic differentiation. However, skeletal muscle was overtly normal in Vgll3-null mice, presumably due to feedback signalling and/or redundancy. This work identifies VGLL3 as a transcriptional co-factor operating with the Hippo signal transduction network to control myogenesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Desenvolvimento Muscular , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células/genética , Regulação da Expressão Gênica , Células HEK293 , Humanos , Camundongos Knockout , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , Neoplasias/metabolismo , Ligação Proteica , Fatores de Transcrição de Domínio TEA , Transcriptoma/genética
11.
Stem Cells ; 35(8): 1958-1972, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28589555

RESUMO

Hippo pathway downstream effectors Yap and Taz play key roles in cell proliferation and regeneration, regulating gene expression especially via Tead transcription factors. To investigate their role in skeletal muscle stem cells, we analyzed Taz in vivo and ex vivo in comparison with Yap. Small interfering RNA knockdown or retroviral-mediated expression of wild-type human or constitutively active TAZ mutants in satellite cells showed that TAZ promoted proliferation, a function shared with YAP. However, at later stages of myogenesis, TAZ also enhanced myogenic differentiation of myoblasts, whereas YAP inhibits such differentiation. Functionally, while muscle growth was mildly affected in Taz (gene Wwtr1-/- ) knockout mice, there were no overt effects on regeneration. Conversely, conditional knockout of Yap in satellite cells of Pax7Cre-ERT2/+ : Yapfl °x/fl °x :Rosa26Lacz mice produced a regeneration deficit. To identify potential mechanisms, microarray analysis showed many common TAZ/YAP target genes, but TAZ also regulates some genes independently of YAP, including myogenic genes such as Pax7, Myf5, and Myod1 (ArrayExpress-E-MTAB-5395). Proteomic analysis revealed many novel binding partners of TAZ/YAP in myogenic cells, but TAZ also interacts with proteins distinct from YAP that are often involved in myogenesis and aspects of cytoskeleton organization (ProteomeXchange-PXD005751). Neither TAZ nor YAP bind members of the Wnt destruction complex but both regulated expression of Wnt and Wnt-cross talking genes with known roles in myogenesis. Finally, TAZ operates through Tead4 to enhance myogenic differentiation. In summary, Taz and Yap have overlapping functions in promoting myoblast proliferation but Taz then switches to enhance myogenic differentiation. Stem Cells 2017;35:1958-1972.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Músculo Esquelético/citologia , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Células-Tronco/metabolismo , Animais , Proteínas de Ciclo Celular , Diferenciação Celular/genética , Fusão Celular , Proliferação de Células , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Via de Sinalização Hippo , Camundongos Knockout , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , Regeneração/genética , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Células-Tronco/citologia , Transativadores , Via de Sinalização Wnt/genética , Proteínas de Sinalização YAP
12.
J Pathol ; 240(1): 3-14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27184927

RESUMO

The Hippo effector YAP has recently been identified as a potent driver of embryonal rhabdomyosarcoma (ERMS). Most reports suggest that the YAP paralogue TAZ (gene symbol WWTR1) functions as YAP but, in skeletal muscle, TAZ has been reported to promote myogenic differentiation, whereas YAP inhibits it. Here, we investigated whether TAZ is also a rhabdomyosarcoma oncogene or whether TAZ acts as a YAP antagonist. Immunostaining of rhabdomyosarcoma tissue microarrays revealed that TAZ is significantly associated with poor survival in ERMS. In 12% of fusion gene-negative rhabdomyosarcomas, the TAZ locus is gained, which is correlated with increased expression. Constitutively active TAZ S89A significantly increased proliferation of C2C12 myoblasts and, importantly, colony formation on soft agar, suggesting transformation. However, TAZ then switches to enhance myogenic differentiation in C2C12 myoblasts, unlike YAP. Conversely, lentiviral shRNA-mediated TAZ knockdown in human ERMS cells reduced proliferation and anchorage-independent growth. While TAZ S89A or YAP1 S127A similarly activated the 8XGTIIC-Luc Hippo reporter, only YAP1 S127A activated the Brachyury (T-box) reporter. Consistent with its oncogene function, TAZ S89A induced expression of the ERMS cancer stem cell gene Myf5 and the serine biosynthesis pathway (Phgdh, Psat1, Psph) in C2C12 myoblasts. Thus, TAZ is associated with poor survival in ERMS and could act as an oncogene in rhabdomyosarcoma. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mioblastos/metabolismo , Rabdomiossarcoma/metabolismo , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Mioblastos/patologia , Prognóstico , Rabdomiossarcoma/genética , Rabdomiossarcoma/mortalidade , Rabdomiossarcoma/patologia , Taxa de Sobrevida , Análise Serial de Tecidos , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
13.
Biochim Biophys Acta ; 1859(7): 906-13, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27060415

RESUMO

Cells and organisms respond to nutrient deprivation by decreasing global rates of transcription, translation and DNA replication. To what extent such changes can be reversed is largely unknown. We examined the effect of maternal dietary restriction on RNA synthesis in the offspring. Low protein diet fed either throughout gestation or for the preimplantation period alone reduced cellular RNA content across fetal somatic tissues during challenge and increased it beyond controls in fetal and adult tissues after challenge release. Changes in transcription of ribosomal RNA, the major component of cellular RNA, were responsible for this phenotype as evidenced by matching alterations in RNA polymerase I density and DNA methylation at ribosomal DNA loci. Cellular levels of the ribosomal transcription factor Rrn3 mirrored the rRNA expression pattern. In cell culture experiments, Rrn3 overexpression reduced rDNA methylation and increased rRNA expression; the converse occurred after inhibition of Rrn3 activity. These observations define novel mechanism where poor nutrition before implantation irreversibly alters basal rates of rRNA transcription thereafter in a process mediated by rDNA methylation and Rrn3 factor.


Assuntos
Implantação do Embrião/genética , Regulação da Expressão Gênica no Desenvolvimento , Fenômenos Fisiológicos da Nutrição Materna , Efeitos Tardios da Exposição Pré-Natal/genética , RNA Ribossômico/genética , Animais , Dieta , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Feminino , Células HEK293 , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia
14.
Reprod Fertil Dev ; 27(4): 684-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25730413

RESUMO

Periconceptional environment may influence embryo development, ultimately affecting adult health. Here, we review the rodent model of maternal low-protein diet specifically during the preimplantation period (Emb-LPD) with normal nutrition during subsequent gestation and postnatally. This model, studied mainly in the mouse, leads to cardiovascular, metabolic and behavioural disease in adult offspring, with females more susceptible. We evaluate the sequence of events from diet administration that may lead to adult disease. Emb-LPD changes maternal serum and/or uterine fluid metabolite composition, notably with reduced insulin and branched-chain amino acids. This is sensed by blastocysts through reduced mammalian target of rapamycin complex 1 signalling. Embryos respond by permanently changing the pattern of development of their extra-embryonic lineages, trophectoderm and primitive endoderm, to enhance maternal nutrient retrieval during subsequent gestation. These compensatory changes include stimulation in proliferation, endocytosis and cellular motility, and epigenetic mechanisms underlying them are being identified. Collectively, these responses act to protect fetal growth and likely contribute to offspring competitive fitness. However, the resulting growth adversely affects long-term health because perinatal weight positively correlates with adult disease risk. We argue that periconception environmental responses reflect developmental plasticity and 'decisions' made by embryos to optimise their own development, but with lasting consequences.


Assuntos
Dieta com Restrição de Proteínas , Proteínas Alimentares , Desenvolvimento Embrionário/fisiologia , Desenvolvimento Fetal/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Animais , Blastocisto/metabolismo , Feminino , Camundongos , Gravidez
15.
BMC Dev Biol ; 15: 3, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25609498

RESUMO

BACKGROUND: Dietary interventions during pregnancy alter offspring fitness. We have shown mouse maternal low protein diet fed exclusively for the preimplantation period (Emb-LPD) before return to normal protein diet (NPD) for the rest of gestation, is sufficient to cause adult offspring cardiovascular and metabolic disease. Moreover, Emb-LPD blastocysts sense altered nutrition within the uterus and activate compensatory cellular responses including stimulated endocytosis within extra-embryonic trophectoderm and primitive endoderm (PE) lineages to protect fetal growth rate. However, these responses associate with later disease. Here, we investigate epigenetic mechanisms underlying nutritional programming of PE that may contribute to its altered phenotype, stabilised during subsequent development. We use embryonic stem (ES) cell lines established previously from Emb-LPD and NPD blastocysts that were differentiated into embryoid bodies (EBs) with outer PE-like layer. RESULTS: Emb-LPD EBs grow to a larger size than NPD EBs and express reduced Gata6 transcription factor (regulator of PE differentiation) at mRNA and protein levels, similar to Emb-LPD PE derivative visceral yolk sac tissue in vivo in later gestation. We analysed histone modifications at the Gata6 promoter in Emb-LPD EBs using chromatin immunoprecipitation assay. We found significant reduction in histone H3 and H4 acetylation and RNA polymerase II binding compared with NPD EBs, all markers of reduced transcription. Other histone modifications, H3K4Me2, H3K9Me3 and H3K27Me3, were unaltered. A similar but generally non-significant histone modification pattern was found on the Gata4 promoter. Consistent with these changes, histone deacetylase Hdac-1, but not Hdac-3, gene expression was upregulated in Emb-LPD EBs. CONCLUSIONS: First, these data demonstrate ES cells and EBs retain and propagate nutritional programming adaptations in vitro, suitable for molecular analysis of mechanisms, reducing animal use. Second, they reveal maternal diet induces persistent changes in histone modifications to regulate Gata6 expression and PE growth and differentiation that may affect lifetime health.


Assuntos
Dieta , Corpos Embrioides/metabolismo , Epigênese Genética , Fator de Transcrição GATA6/genética , Histona Desacetilases/genética , Histonas/metabolismo , Acetilação , Animais , Corpos Embrioides/enzimologia , Células-Tronco Embrionárias/metabolismo , Feminino , Histona Desacetilases/metabolismo , Camundongos , Regiões Promotoras Genéticas
16.
Development ; 141(5): 1140-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24504338

RESUMO

Mammalian extra-embryonic lineages perform the crucial role of nutrient provision during gestation to support embryonic and fetal growth. These lineages derive from outer trophectoderm (TE) and internal primitive endoderm (PE) in the blastocyst and subsequently give rise to chorio-allantoic and visceral yolk sac placentae, respectively. We have shown maternal low protein diet exclusively during mouse preimplantation development (Emb-LPD) is sufficient to cause a compensatory increase in fetal and perinatal growth that correlates positively with increased adult-onset cardiovascular, metabolic and behavioural disease. Here, to investigate early mechanisms of compensatory nutrient provision, we assessed the influence of maternal Emb-LPD on endocytosis within extra-embryonic lineages using quantitative imaging and expression of markers and proteins involved. Blastocysts collected from Emb-LPD mothers within standard culture medium displayed enhanced TE endocytosis compared with embryos from control mothers with respect to the number and collective volume per cell of vesicles with endocytosed ligand and fluid and lysosomes, plus protein expression of megalin (Lrp2) LDL-family receptor. Endocytosis was also stimulated using similar criteria in the outer PE-like lineage of embryoid bodies formed from embryonic stem cell lines generated from Emb-LPD blastocysts. Using an in vitro model replicating the depleted amino acid (AA) composition found within the Emb-LPD uterine luminal fluid, we show TE endocytosis response is activated through reduced branched-chain AAs (leucine, isoleucine, valine). Moreover, activation appears mediated through RhoA GTPase signalling. Our data indicate early embryos regulate and stabilise endocytosis as a mechanism to compensate for poor maternal nutrient provision.


Assuntos
Endocitose/fisiologia , Animais , Blastocisto/citologia , Células Cultivadas , Dieta com Restrição de Proteínas , Endoderma/citologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Masculino , Camundongos , Gravidez , Proteína rhoA de Ligação ao GTP/metabolismo
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(3): 711-4, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18536450

RESUMO

The interaction of glipizide and hydroxypropyl-pcyclodextrin was investigated in the present paper. The stability constant and molar ratio of glipizide and hydroxypropyl-beta-cyclodextrin was calculated from the phase soluility diagram. The solid state inclusion complex of hydroxypropyl-beta-cyclodextrin/glipizide prepared by neutralization method was characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). It was found that the phase solubility diagram of the HP-beta-CD solution showed a typical AL-type, suggesting the formation of a soluble complex of 1 : 1 molar ratio, and the stability constant was 359 L x mol(-1) at 25 degrees C. The spectra of IR, thermograph of DSC and XRD pattern of the inclusion complex were remarkably different from the glipizide and hydroxypropyl-beta-cyclodextrin/glipizide physical mixture, and indicated that hydroxypropyl-beta-cyclodextrin/glipizide inclusion complex displayed amorphous characteristic. The experiment of solubility of inclusion complex indicated that the solubility of inclusion complex increased 25-fold.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Glipizida/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos , beta-Ciclodextrinas/análise , 2-Hidroxipropil-beta-Ciclodextrina , Glipizida/química , Solubilidade , beta-Ciclodextrinas/química
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