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1.
Mol Plant Microbe Interact ; 32(11): 1508-1516, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31230563

RESUMO

During interactions, both plants and pathogens produce reactive oxygen species (ROS). Plants generate ROS for defense induction, while pathogens synthesize ROS for growth, sporulation, and virulence. NADPH oxidase (NOX) complex in the plasma membrane represents a main protein complex for ROS production in pathogens. Although NOX plays a crucial role in pathogenicity of pathogens, the underlying molecular mechanisms of NOX, especially the proteins regulated by NOX, remain largely unknown. Here, we applied an iodoacetyl tandem mass tag-based redox proteomic assay to investigate the protein redox dynamics in deletion mutant of bcnoxR, which encodes a regulatory subunit of NOX in the fungal pathogen Botrytis cinerea. In total, 214 unique peptidyl cysteine (Cys) thiols from 168 proteins were identified and quantified in both the wild type and ∆bcnoxR mutant. The Cys thiols in the ∆bcnoxR mutant were generally more oxidized than those in the wild type, suggesting that BcNoxR is essential for maintaining the equilibrium of the redox state in B. cinerea. Site-specific thiol oxidation analysis indicated that 142 peptides containing the oxidized thiols changed abundance significantly in the ∆bcnoxR mutant. Proteins containing these differential peptides are classified into various functional categories. Functional analysis revealed that one of these proteins, 6-phosphate dehydrogenase, played roles in oxidative stress response and pathogenesis of B. cinerea. These results provide insight into the potential target proteins and the ROS signal transduction pathway regulated by NOX.


Assuntos
Botrytis , Homeostase , NADPH Oxidases , Botrytis/enzimologia , Botrytis/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Homeostase/genética , Mutação , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Oxirredução , Proteômica , Espécies Reativas de Oxigênio , Transdução de Sinais
2.
Nat Commun ; 10(1): 2581, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197173

RESUMO

Despite existing reports on differential DNA methylation in type 2 diabetes (T2D) and obesity, our understanding of its functional relevance remains limited. Here we show the effect of differential methylation in the early phases of T2D pathology by a blood-based epigenome-wide association study of 4808 non-diabetic Europeans in the discovery phase and 11,750 individuals in the replication. We identify CpGs in LETM1, RBM20, IRS2, MAN2A2 and the 1q25.3 region associated with fasting insulin, and in FCRL6, SLAMF1, APOBEC3H and the 15q26.1 region with fasting glucose. In silico cross-omics analyses highlight the role of differential methylation in the crosstalk between the adaptive immune system and glucose homeostasis. The differential methylation explains at least 16.9% of the association between obesity and insulin. Our study sheds light on the biological interactions between genetic variants driving differential methylation and gene expression in the early pathogenesis of T2D.


Assuntos
Metilação de DNA/fisiologia , Diabetes Mellitus Tipo 2/genética , Glucose/metabolismo , Insulina/metabolismo , Obesidade/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Ilhas de CpG/genética , Diabetes Mellitus Tipo 2/metabolismo , Epigênese Genética/fisiologia , Epigenômica/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla/métodos , Homeostase/genética , Humanos , Masculino , Redes e Vias Metabólicas/genética , Pessoa de Meia-Idade , Obesidade/metabolismo , Polimorfismo de Nucleotídeo Único/fisiologia , Adulto Jovem
3.
Cell Mol Life Sci ; 76(20): 4071-4102, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254043

RESUMO

Mammalian spermatogenesis is a highly complex multi-step process sustained by a population of mitotic germ cells with self-renewal potential known as spermatogonial stem cells (SSCs). The maintenance and regulation of SSC function are strictly dependent on a supportive niche that is composed of multiple cell types. A detailed appreciation of the molecular mechanisms underpinning SSC activity and fate is of fundamental importance for spermatogenesis and male fertility. However, different models of SSC identity and spermatogonial hierarchy have been proposed and recent studies indicate that cell populations supporting steady-state germline maintenance and regeneration following damage are distinct. Importantly, dynamic changes in niche properties may underlie the fate plasticity of spermatogonia evident during testis regeneration. While formation of spermatogenic colonies in germ-cell-depleted testis upon transplantation is a standard assay for SSCs, differentiation-primed spermatogonial fractions have transplantation potential and this assay provides readout of regenerative rather than steady-state stem cell capacity. The characterisation of spermatogonial populations with regenerative capacity is essential for the development of clinical applications aimed at restoring fertility in individuals following germline depletion by genotoxic treatments. This review will discuss regulatory mechanisms of SSCs in homeostatic and regenerative testis and the conservation of these mechanisms between rodent models and man.


Assuntos
Fertilidade/genética , Infertilidade Masculina/genética , Espermatogênese/genética , Espermatogônias/citologia , Células-Tronco/citologia , Testículo/citologia , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Homeostase/genética , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Modelos Genéticos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Espermatogônias/metabolismo , Nicho de Células-Tronco/genética , Células-Tronco/metabolismo , Testículo/metabolismo
4.
Nat Commun ; 10(1): 2701, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221965

RESUMO

One of the biggest hurdles for the development of metabolism-targeted therapies is to identify the responsive tumor subsets. However, the metabolic vulnerabilities for most human cancers remain unclear. Establishing the link between metabolic signatures and the oncogenic alterations of receptor tyrosine kinases (RTK), the most well-defined cancer genotypes, may precisely direct metabolic intervention to a broad patient population. By integrating metabolomics and transcriptomics, we herein show that oncogenic RTK activation causes distinct metabolic preference. Specifically, EGFR activation branches glycolysis to the serine synthesis for nucleotide biosynthesis and redox homeostasis, whereas FGFR activation recycles lactate to fuel oxidative phosphorylation for energy generation. Genetic alterations of EGFR and FGFR stratify the responsive tumors to pharmacological inhibitors that target serine synthesis and lactate fluxes, respectively. Together, this study provides the molecular link between cancer genotypes and metabolic dependency, providing basis for patient stratification in metabolism-targeted therapies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Mutação com Ganho de Função , Perfilação da Expressão Gênica/métodos , Glicólise/efeitos dos fármacos , Glicólise/genética , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Metabolômica/métodos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Seleção de Pacientes , Inibidores de Proteínas Quinases/farmacologia , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Serina/biossíntese , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nat Immunol ; 20(6): 687-700, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061528

RESUMO

Most tissue-resident macrophage populations develop during embryogenesis, self-renew in the steady state and expand during type 2 immunity. Whether shared mechanisms regulate the proliferation of macrophages in homeostasis and disease is unclear. Here we found that the transcription factor Bhlhe40 was required in a cell-intrinsic manner for the self-renewal and maintenance of large peritoneal macrophages (LPMs), but not that of other tissue-resident macrophages. Bhlhe40 was necessary for the proliferation, but not the polarization, of LPMs in response to the cytokine IL-4. During infection with the helminth Heligmosomoides polygyrus bakeri, Bhlhe40 was required for cell cycling of LPMs. Bhlhe40 repressed the expression of genes encoding the transcription factors c-Maf and Mafb and directly promoted expression of transcripts encoding cell cycle-related proteins to enable the proliferation of LPMs. In LPMs, Bhlhe40 bound to genomic sites co-bound by the macrophage lineage-determining factor PU.1 and to unique sites, including Maf and loci encoding cell-cycle-related proteins. Our findings demonstrate a tissue-specific control mechanism that regulates the proliferation of resident macrophages in homeostasis and type 2 immunity.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Homeodomínio/genética , Homeostase/genética , Homeostase/imunologia , Imunidade/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores , Ciclo Celular/genética , Ciclo Celular/imunologia , Proliferação de Células , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Infecções por Helicobacter/genética , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Proteínas de Homeodomínio/metabolismo , Imunofenotipagem , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Transgênicos , Monócitos/imunologia , Monócitos/metabolismo , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Transcriptoma
6.
Int J Mol Sci ; 20(10)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31100819

RESUMO

Iron is an essential element for plant growth and development. While abundant in soil, the available Fe in soil is limited. In this regard, plants have evolved a series of mechanisms for efficient iron uptake, allowing plants to better adapt to iron deficient conditions. These mechanisms include iron acquisition from soil, iron transport from roots to shoots, and iron storage in cells. The mobilization of Fe in plants often occurs via chelating with phytosiderophores, citrate, nicotianamine, mugineic acid, or in the form of free iron ions. Recent work further elucidates that these genes' response to iron deficiency are tightly controlled at transcriptional and posttranscriptional levels to maintain iron homeostasis. Moreover, increasing evidences shed light on certain factors that are identified to be interconnected and integrated to adjust iron deficiency. In this review, we highlight the molecular and physiological bases of iron acquisition from soil to plants and transport mechanisms for tolerating iron deficiency in dicotyledonous plants and rice.


Assuntos
Transporte Biológico/fisiologia , Homeostase/fisiologia , Ferro/metabolismo , Plantas/metabolismo , Ácido Azetidinocarboxílico/análogos & derivados , Transporte Biológico/genética , Ácido Cítrico , Regulação da Expressão Gênica de Plantas , Homeostase/genética , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Plantas/genética , Sideróforos
7.
Biomed Res Int ; 2019: 9616248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032369

RESUMO

Background: Plasma membrane Ca2+-ATPase (PMCA) is the most sensitive cellular calcium detector. It exists in four main isoforms (PMCA1-4), among which PMCA2 and PMCA3 are considered as fast-acting neuron-specific forms. In the brain, PMCA function declines progressively during aging; thereby impaired calcium homeostasis may contribute to some neurodegenerative diseases. These destructive processes can be propagated by proinflammatory chemokines, including chemokine CCL5, which causes phospholipase C-mediated liberation of Ca2+ from endoplasmic reticulum by IP3-gated channels. Methods: To mimic the changes in aged neurons we used stable transfected differentiated PC12 cells with downregulated PMCA2 or PMCA3 and analyzed the effect of CCL5 on calcium transients with Fluo-4 reagent. Chemokine receptors were evaluated using Western blot, and IP3 receptors expression level was assessed using qRT-PCR and Western blot. Results: In PMCA-reduced cell lines, CCL5 released more Ca2+ by IP3-sensitive receptors, and the time required for Ca2+ clearance was significantly longer. Also, in these lines we detected altered expression level of CCR5 and IP3 receptors. Conclusion: Although modification of PMCAs composition could provide some protection against calcium overload, reduction of PMCA2 appeared to be more detrimental to the cells than deficiency of PMCA3. Under pathological conditions, including inflammatory CCL5 action and long-lasting Ca2+ dyshomeostasis, insufficient cell protection may result in progressive degeneration and death of neurons.


Assuntos
Encéfalo/metabolismo , Quimiocina CCL5/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Compostos de Anilina/farmacologia , Animais , Encéfalo/patologia , Cálcio/metabolismo , Sinalização do Cálcio/genética , Morte Celular/genética , Diferenciação Celular/genética , Membrana Celular/genética , Homeostase/genética , Humanos , Neurônios/metabolismo , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos , Xantenos/farmacologia
8.
J Mol Histol ; 50(3): 285-294, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30993430

RESUMO

The aim of this study was to ascertain whether, like many cell types in cartilaginous tissues if type XI collagen was a pericellular component of annulus fibrosus (AF) cells and chondrocytes. Fine fibrillar networks were visualised which were perlecan, HS (MAb 10E4) and type XI collagen positive. Heparitinase-III pre-digestion abolished the type XI collagen and 10E4 localisation in these fibrillar assemblies demonstrating a putative HS mediated interaction which localised the type XI collagen. Type XI collagen was confirmed to be present in the Heparitinase III treated AF monolayer media samples by immunoblotting. Heparitinase-III generated ΔHS stub epitopes throughout these fibrillar networks strongly visualised by MAb 3-G-10. Monolayers of murine hip articular chondrocytes from C57BL/6 and Hspg2 exon 3 null mice also displayed pericellular perlecan localisations, however type XI collagen was only evident in the Wild type mice. Perlecan was also immunolocalised in control and murine knee articular cartilage from the two mouse genotypes subjected to a medial meniscal destabilisation procedure which induces OA. This resulted in a severe depletion of perlecan levels particularly in the perlecan exon 3 null mice and was consistent with OA representing a disease of the pericellular matrix. A model was prepared to explain these observations between the NPP type XI collagen domain and HS chains of perlecan domain-I in the pericellular matrix of AF cells which likely contributed to cellular communication, tissue stabilization and the regulation of extracellular matrix homeostasis.


Assuntos
Anel Fibroso/efeitos dos fármacos , Colágeno Tipo XI/genética , Proteoglicanas de Heparan Sulfato/genética , Animais , Anel Fibroso/metabolismo , Anel Fibroso/patologia , Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/metabolismo , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Éxons/genética , Matriz Extracelular/genética , Proteínas da Matriz Extracelular/genética , Homeostase/genética , Disco Intervertebral/crescimento & desenvolvimento , Disco Intervertebral/metabolismo , Camundongos , Polissacarídeo-Liase/farmacologia
9.
Nucleic Acids Res ; 47(8): 4086-4110, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30986824

RESUMO

Ataxia with oculomotor apraxia type 1 (AOA1) is an early onset progressive spinocerebellar ataxia caused by mutation in aprataxin (APTX). APTX removes 5'-AMP groups from DNA, a product of abortive ligation during DNA repair and replication. APTX deficiency has been suggested to compromise mitochondrial function; however, a detailed characterization of mitochondrial homeostasis in APTX-deficient cells is not available. Here, we show that cells lacking APTX undergo mitochondrial stress and display significant changes in the expression of the mitochondrial inner membrane fusion protein optic atrophy type 1, and components of the oxidative phosphorylation complexes. At the cellular level, APTX deficiency impairs mitochondrial morphology and network formation, and autophagic removal of damaged mitochondria by mitophagy. Thus, our results show that aberrant mitochondrial function is a key component of AOA1 pathology. This work corroborates the emerging evidence that impaired mitochondrial function is a characteristic of an increasing number of genetically diverse neurodegenerative disorders.


Assuntos
Proteínas de Ligação a DNA/genética , GTP Fosfo-Hidrolases/genética , Mitocôndrias/genética , Degradação Mitocondrial/genética , Proteínas Nucleares/genética , Ataxias Espinocerebelares/congênito , Linhagem Celular Transformada , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/deficiência , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , GTP Fosfo-Hidrolases/deficiência , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Homeostase/genética , Humanos , Linfócitos/metabolismo , Linfócitos/patologia , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Nucleares/deficiência , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/metabolismo , Osteoblastos/patologia , Fosforilação Oxidativa , Transdução de Sinais , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/metabolismo , Ataxias Espinocerebelares/patologia
10.
Nature ; 568(7751): 187-192, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30944478

RESUMO

Microglia maintain homeostasis in the central nervous system through phagocytic clearance of protein aggregates and cellular debris. This function deteriorates during ageing and neurodegenerative disease, concomitant with cognitive decline. However, the mechanisms of impaired microglial homeostatic function and the cognitive effects of restoring this function remain unknown. We combined CRISPR-Cas9 knockout screens with RNA sequencing analysis to discover age-related genetic modifiers of microglial phagocytosis. These screens identified CD22, a canonical B cell receptor, as a negative regulator of phagocytosis that is upregulated on aged microglia. CD22 mediates the anti-phagocytic effect of α2,6-linked sialic acid, and inhibition of CD22 promotes the clearance of myelin debris, amyloid-ß oligomers and α-synuclein fibrils in vivo. Long-term central nervous system delivery of an antibody that blocks CD22 function reprograms microglia towards a homeostatic transcriptional state and improves cognitive function in aged mice. These findings elucidate a mechanism of age-related microglial impairment and a strategy to restore homeostasis in the ageing brain.


Assuntos
Envelhecimento/fisiologia , Encéfalo/citologia , Homeostase/efeitos dos fármacos , Microglia/efeitos dos fármacos , Ácido N-Acetilneuramínico/farmacologia , Fagocitose/efeitos dos fármacos , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/antagonistas & inibidores , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Cognição/efeitos dos fármacos , Cognição/fisiologia , Feminino , Homeostase/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Ácido N-Acetilneuramínico/química , Fagocitose/genética , Análise de Sequência de RNA , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/genética , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo
11.
Gene ; 704: 15-24, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30965128

RESUMO

OBJECTIVE: The objective of our study was to verify the hypothesis that the expression of connective tissue growth factor (CTGF/CCN2), a key molecule essential for the maintenance of nucleus pulposus (NP) matrix homeostasis, is regulated by osmolarity and intracellular calcium in NP cells. METHODS: Gene and protein expression levels of CCN2 were assessed using quantitative real-time PCR and western blot. Transfections and dual luciferase assays were performed to measure the effect of hyperosmolarity, tonicity enhancer binding protein (TonEBP) and Ca2+-calcineurin (Cn)-NFAT signaling on CCN2 promoter activity. RESULTS: Cultured in hyperosmotic media, there was a significant decrease in the levels of CCN2 promoter activity, gene and protein expression in NP cells. The JASPAR database was used to analyze the construction of human CCN2 promoter, we found conserved TonE and NFAT binding sites. We then investigated whether TonEBP controlled CCN2 expression. Forced expression of TonEBP in NP cells showed that TonEBP negatively regulated CCN2 promoter activity, while suppression of TonEBP induced CCN2 promoter activity and expression. We then examined if Ca2+-Cn-NFAT signaling participated in the regulation of CCN2 expression. Co-expression of CCN2 reporter with individual NFAT1-4 expression plasmids and/or calcineurin A/B constructs suggested this signaling pathway played a role in the regulation of CCN2expression in NP cells. CONCLUSIONS: Results of these studies illustrated that the expression of CCN2 in NP cells was regulated by the NFAT family through a signaling pathway network involving both activator (Ca2+-Cn-NFAT signaling) and suppressor (Hyperosmolarity-TonEBP) molecules.


Assuntos
Cálcio/farmacologia , Fator de Crescimento do Tecido Conjuntivo/genética , Núcleo Pulposo/efeitos dos fármacos , Núcleo Pulposo/metabolismo , Equilíbrio Hidroeletrolítico , Animais , Células Cultivadas , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/genética , Masculino , Fatores de Transcrição NFATC/fisiologia , Concentração Osmolar , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/fisiologia , Desequilíbrio Hidroeletrolítico/genética , Desequilíbrio Hidroeletrolítico/metabolismo
12.
Nano Lett ; 19(5): 3040-3048, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30968694

RESUMO

Exosomes, also known as extracellular vesicles, are naturally occurring, biocompatible, and bioacive nanoparticles ranging from 40 to 150 nm in diameter. Bone-secreted exosomes play important roles in bone homeostasis, the interruption of which can lead to diseases such as osteoporosis, rheumatoid arthritis, and osteopetrosis. Though the relationship between vascular and bone homeostasis has been recognized recently, the role of vascular endothelial cell (EC)-secreted exosomes (EC-Exos) in bone homeostasis is not well understood. Herein, we found that EC-Exos show more efficient bone targeting than osteoblast-derived exosomes or bone marrow mesenchymal stem cell-derived exosomes. We also found that EC-Exos can be internalized by bone marrow-derived macrophages (BMMs) to alter their morphology. EC-Exos can inhibit osteoclast activity in vitro and inhibit osteoporosis in an ovariectomized mouse model. Sequencing of exosome miRNA revealed that miR-155 was highly expressed in EC-Exos-treated BMMs. The miR-155 level in EC-Exos was much higher than that in BMMs and ECs, indicating that miR-155 was endogenous cargo of EC-derived vesicles. Blockage of BMMs miR-155 levels reversed the suppression by EC-Exos of osteoclast induction, confirming that exosomal miR-155 may have therapeutic potential against osteoporosis. Taken together, our findings suggest that EC-Exos may be utilized as a bone targeting and nontoxic nanomedicine for the treatment of bone resorption disorders.


Assuntos
Exossomos/química , Homeostase/efeitos dos fármacos , MicroRNAs/genética , Osteoporose/tratamento farmacológico , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/química , Células Endoteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/genética , Humanos , Macrófagos/química , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , MicroRNAs/química , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteócitos/química , Osteócitos/efeitos dos fármacos , Osteoporose/patologia
13.
Nat Commun ; 10(1): 1827, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015444

RESUMO

The Tip60/p400 chromatin-modifying complex, which is involved in the incorporation and post-translational modification of the H2A.Z histone variant, regulates cell proliferation and important signaling pathways, such as Wnt. Here, we study the involvement of H2A.Z in intestinal epithelial homeostasis, which is dependent on the finely-tuned equilibrium between stem cells renewal and differentiation, under the control of such pathway. We use cell models and inducible knock-out mice to study the impact of H2A.Z depletion on intestinal homeostasis. We show that H2A.Z is essential for the proliferation of human cancer and normal intestinal crypt cells and negatively controls the expression of a subset of differentiation markers, in cultured cells and mice. H2A.Z impairs the recruitment of the intestine-specific transcription factor CDX2 to chromatin, is itself a target of the Wnt pathway and thus, acts as an integrator for Wnt signaling in the control of intestinal epithelial cell fate and homeostasis.


Assuntos
Histonas/metabolismo , Homeostase/genética , Mucosa Intestinal/fisiologia , Via de Sinalização Wnt/genética , Animais , Fator de Transcrição CDX2/genética , Fator de Transcrição CDX2/metabolismo , Células CACO-2 , Diferenciação Celular/genética , Proliferação de Células/genética , Cromatina/genética , Células Epiteliais/fisiologia , Regulação da Expressão Gênica/fisiologia , Células HCT116 , Histonas/genética , Humanos , Mucosa Intestinal/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
14.
Turk J Med Sci ; 49(2): 490-496, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-30866603

RESUMO

Background/aim: Genetic aspects play a role in insulin resistance in children. In this study, for the first time, the association of LRP5 (rs556442) polymorphism and insulin resistance in Iranian children and adolescents was investigated. Materials and methods: The study population comprises children and adolescents aged 9­18 years. Anthropometric and biochemical parameters were assessed. Insulin resistance/sensitivity was determined by the quantitative insulin sensitivity check index (QUICKI), homeostasis model assessment-insulin resistance (HOMA-IR), insulin-to-glucose ratio, McAuley index, revised McAuley index, fasting insulin resistance index (FIRI), and Bennett's index. LRP5 (rs566442) single nucleotide polymorphism (SNP) was identified using restriction fragment length polymorphism (RFLP). Linear regression analysis was used to determine the association between the LRP5 polymorphism (rs556442) and insulin sensitivity indexes. Results: Significant differences were found between GG genotype vs. AG/AA genotypes for McAuley index (P = 0.049) and revised McAuley index (P = 0.044) when adjusted for interaction factors (age, sex, and puberty) in regression models. No significant association was found between LRP5 (rs566442) and other insulin resistance indexes. Also, LRP5 (rs566442) did not show a significant impact on biochemical parameters. Conclusion: This study showed that LRP5 polymorphism (rs556442) was associated with insulin resistance in Iranian children and adolescents.


Assuntos
Resistência à Insulina/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Criança , Estudos Transversais , Feminino , Predisposição Genética para Doença , Teste de Tolerância a Glucose , Voluntários Saudáveis , Homeostase/genética , Humanos , Irã (Geográfico) , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/fisiologia , Masculino , População Urbana
15.
Biomed Res Int ; 2019: 4504302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30834265

RESUMO

Background: Extramedullary hematopoiesis (EMH) is common in non-transfusion-dependent thalassemia (NTDT) patients. Clinical presentations of EMH vary as MRI screening is not feasible. Hence, serum biomarkers are used to predict the risk of EMH. Materials and Methods: 52 NTDT patients, including 26 EMH (+) and 26 EMH (-), together with 26 healthy controls, were enrolled in this case-control study from 2013 to 2016. EMH was confirmed by computed tomography or MRI. Demographic, transfusion, genetic, laboratory, and liver iron concentration (LIC) data, as well as clinical complications, were analyzed. Results: EMH (+) patients had significantly higher serum ferritin (SF), growth differentiation factor 15 (GDF15), and erythropoietin (EPO) levels compared with EMH (-) patients and controls. The levels of erythroferrone (ERFE), hepcidin, and sTfR did not differ significantly between EMH (+) and EMH (-) patients (p>0.05). In NTDT patients, serum ERFE was not related to SF, LIC, hepcidin, sTfR, EPO, GDF15, and Hb levels. GDF15, EPO concentrations, and GDF15 to sTfR and GDF15 to EPO ratios are able to determine the presence of EMH with considerable sensitivity and specificity. Conclusions: GDF15, EPO, and GDF15 to EPO and GDF15 to sTfR ratios are potential biomarkers for the early prediction of NTDT in patients who are at risk for EMH.


Assuntos
Antígenos CD/sangue , Eritropoetina/sangue , Fator 15 de Diferenciação de Crescimento/sangue , Hematopoese Extramedular/genética , Receptores da Transferrina/sangue , Talassemia/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Eritropoese/genética , Feminino , Ferritinas/sangue , Hematopoese Extramedular/fisiologia , Hepcidinas/sangue , Homeostase/genética , Humanos , Ferro/metabolismo , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Hormônios Peptídicos/sangue , Fatores de Risco , Talassemia/complicações , Talassemia/diagnóstico por imagem , Talassemia/fisiopatologia , Tomografia Computadorizada por Raios X
16.
Science ; 363(6431)2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30846568

RESUMO

Commensal bacteria influence host physiology, without invading host tissues. We show that proteins from segmented filamentous bacteria (SFB) are transferred into intestinal epithelial cells (IECs) through adhesion-directed endocytosis that is distinct from the clathrin-dependent endocytosis of invasive pathogens. This process transfers microbial cell wall-associated proteins, including an antigen that stimulates mucosal T helper 17 (TH17) cell differentiation, into the cytosol of IECs in a cell division control protein 42 homolog (CDC42)-dependent manner. Removal of CDC42 activity in vivo led to disruption of endocytosis induced by SFB and decreased epithelial antigen acquisition, with consequent loss of mucosal TH17 cells. Our findings demonstrate direct communication between a resident gut microbe and the host and show that under physiological conditions, IECs acquire antigens from commensal bacteria for generation of T cell responses to the resident microbiota.


Assuntos
Antígenos de Bactérias/imunologia , Endocitose/imunologia , Microbioma Gastrointestinal/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Mucosa Intestinal/imunologia , Linfócitos Intraepiteliais/imunologia , Células Th17/imunologia , Animais , Bactérias/imunologia , Endocitose/genética , Homeostase/genética , Ativação Linfocitária , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Simbiose , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/fisiologia
17.
Nature ; 568(7750): 93-97, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30918407

RESUMO

Sodium is the main cation in the extracellular fluid and it regulates various physiological functions. Depletion of sodium in the body increases the hedonic value of sodium taste, which drives animals towards sodium consumption1,2. By contrast, oral sodium detection rapidly quenches sodium appetite3,4, suggesting that taste signals have a central role in sodium appetite and its satiation. Nevertheless, the neural mechanisms of chemosensory-based appetite regulation remain poorly understood. Here we identify genetically defined neural circuits in mice that control sodium intake by integrating chemosensory and internal depletion signals. We show that a subset of excitatory neurons in the pre-locus coeruleus express prodynorphin, and that these neurons are a critical neural substrate for sodium-intake behaviour. Acute stimulation of this population triggered robust ingestion of sodium even from rock salt, while evoking aversive signals. Inhibition of the same neurons reduced sodium consumption selectively. We further demonstrate that the oral detection of sodium rapidly suppresses these sodium-appetite neurons. Simultaneous in vivo optical recording and gastric infusion revealed that sodium taste-but not sodium ingestion per se-is required for the acute modulation of neurons in the pre-locus coeruleus that express prodynorphin, and for satiation of sodium appetite. Moreover, retrograde-virus tracing showed that sensory modulation is in part mediated by specific GABA (γ-aminobutyric acid)-producing neurons in the bed nucleus of the stria terminalis. This inhibitory neural population is activated by sodium ingestion, and sends rapid inhibitory signals to sodium-appetite neurons. Together, this study reveals a neural architecture that integrates chemosensory signals and the internal need to maintain sodium balance.


Assuntos
Regulação do Apetite/efeitos dos fármacos , Regulação do Apetite/fisiologia , Ingestão de Alimentos/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Sódio/farmacologia , Paladar/efeitos dos fármacos , Paladar/fisiologia , Administração Oral , Animais , Regulação do Apetite/genética , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Ingestão de Alimentos/genética , Ingestão de Alimentos/fisiologia , Encefalinas/metabolismo , Feminino , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/metabolismo , Homeostase/efeitos dos fármacos , Homeostase/genética , Homeostase/fisiologia , Locus Cerúleo/citologia , Locus Cerúleo/efeitos dos fármacos , Locus Cerúleo/fisiologia , Masculino , Camundongos , Motivação/efeitos dos fármacos , Vias Neurais/citologia , Vias Neurais/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Precursores de Proteínas/metabolismo , Resposta de Saciedade/efeitos dos fármacos , Resposta de Saciedade/fisiologia , Sódio/administração & dosagem , Paladar/genética
18.
Cell Physiol Biochem ; 52(3): 455-467, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873821

RESUMO

BACKGROUND/AIMS: Transient receptor potential canonical 6 (TRPC6) protein is a nonselective cation channel permitting the uptake of essential elements such as iron (Fe) and zinc (Zn). TRPC6 is found throughout the body with high expression levels in the placenta. However, its role in this organ is still to be determined. To further advance our understanding of the physiological relevance of TRPC6, we have studied the placental histology, pregnancy outcome and the Fe and Zn status of organs (placenta, brain, kidney, liver and lung) collected from TRPC6 deficient (TRPC6-/-) mice and sex and age-matched C57Bl6/J and B6129SF2/J mice. METHODS: Metal content was quantified by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Quantitative reverse transcriptase PCR (qRT-PCR) and Western Blottings (WB) were performed to analyze the expression of placental markers and TRPC6. RESULTS: Our data show that TRPC6-/- mice displayed reduced litter sizes, structural changes of the placenta, along with altered mRNA levels of CD31 and Gcm1, two markers of placental development. Furthermore, immunoblots revealed elevated amounts of TRPC6 proteins in placentas from women diagnosed with preeclampsia, a common gestational disease. When compared to C57Bl6/J and B6129SF2/J, TRPC6-/- mice had elevated Zn levels in placenta, liver and kidney during embryonic development and postnatally, but not at adulthood. High amounts of Fe were found in the adult brain and liver of TRPC6-/- mice. The lung was however not affected by the deletion of TRPC6, indicating that this mouse strain developed organ and age-dependent perturbations in their Zn and Fe status. CONCLUSION: This work indicates that TRPC6 exerts critical pathophysiological functions in placenta, and provides further evidence for a role of this channel in the homeostasis of cations like Zn and Fe.


Assuntos
Encéfalo/metabolismo , Ferro/metabolismo , Fígado/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/genética , Canais de Cátion TRPC/genética , Zinco/metabolismo , Adulto , Animais , Cátions Bivalentes , Feminino , Expressão Gênica , Homeostase/genética , Humanos , Transporte de Íons , Rim/metabolismo , Tamanho da Ninhada de Vivíparos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Canais de Cátion TRPC/deficiência
19.
Aquat Toxicol ; 210: 30-43, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30822701

RESUMO

Sentinel species such as the Atlantic killifish (Fundulus heteroclitus) living in urban waterways can be used as toxicological models to understand impacts of environmental metabolism disrupting compound (MDC) exposure on both wildlife and humans. Exposure to MDCs is associated with increased risk of metabolic syndrome, including impaired lipid and glucose homeostasis, adipogenesis, appetite control, and basal metabolism. MDCs are ubiquitous in the environment, including in aquatic environments. New Bedford Harbor (NBH), Massachusetts is polluted with polychlorinated biphenyls (PCBs), and, as we show for the first time, tin (Sn). PCBs and organotins are ligands for two receptor systems known to regulate lipid homeostasis, the aryl hydrocarbon receptor (AHR) and the peroxisome proliferator-activated receptors (PPARs), respectively. In the current study, we compared lipid homeostasis in laboratory-reared killifish from NBH (F2) and a reference location (Scorton Creek, Massachusetts; F1 and F2) to evaluate how adaptation to local conditions may influence responses to MDCs. Adult killifish from each population were exposed to 3,3',4,4',5-pentachlorobiphenyl (PCB126, dioxin-like), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153, non-dioxin-like), or tributyltin (TBT, a PPARγ ligand) by a single intraperitoneal injection and analyzed after 3 days. AHR activation was assessed by measuring cyp1a mRNA expression. Lipid homeostasis was evaluated phenotypically by measuring liver triglycerides and organosomatic indices, and at the molecular level by measuring the mRNA expression of pparg and ppara and a target gene for each receptor. Acute MDC exposure did not affect phenotypic outcomes. However, overall NBH killifish had higher liver triglycerides and adiposomatic indices than SC killifish. Both season and population were significant predictors of the lipid phenotype. Acute MDC exposure altered hepatic gene expression only in male killifish from SC. PCB126 exposure induced cyp1a and pparg, whereas PCB153 exposure induced ppara. TBT exposure did not induce ppar-dependent pathways. Comparison of lipid homeostasis in two killifish populations extends our understanding of how MDCs act on fish and provides a basis to infer adaptive benefits of these differences in the wild.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Fundulidae/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Bifenilos Policlorados/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Exposição Ambiental/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/genética , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Massachusetts , Receptores de Hidrocarboneto Arílico/genética
20.
Int J Mol Sci ; 20(6)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871211

RESUMO

To unravel the molecular mechanisms underpinning maize (Zea mays L.) drought stress tolerance, we conducted comprehensive comparative transcriptome and physiological analyses of drought-tolerant YE8112 and drought-sensitive MO17 inbred line seedlings that had been exposed to drought treatment for seven days. Resultantly, YE8112 seedlings maintained comparatively higher leaf relative water and proline contents, greatly increased peroxidase activity, but decreased malondialdehyde content, than MO17 seedlings. Using an RNA sequencing (RNA-seq)-based approach, we identified a total of 10,612 differentially expressed genes (DEGs). From these, we mined out four critical sets of drought responsive DEGs, including 80 specific to YE8112, 5140 shared between the two lines after drought treatment (SD_TD), five DEGs of YE8112 also regulated in SD_TD, and four overlapping DEGs between the two lines. Drought-stressed YE8112 DEGs were primarily associated with nitrogen metabolism and amino-acid biosynthesis pathways, whereas MO17 DEGs were enriched in the ribosome pathway. Additionally, our physiological analyses results were consistent with the predicted RNA-seq-based findings. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis and the RNA-seq results of twenty representative DEGs were highly correlated (R² = 98.86%). Crucially, tolerant line YE8112 drought-responsive genes were predominantly implicated in stress signal transduction; cellular redox homeostasis maintenance; MYB, NAC, WRKY, and PLATZ transcriptional factor modulated; carbohydrate synthesis and cell-wall remodeling; amino acid biosynthesis; and protein ubiquitination processes. Our findings offer insights into the molecular networks mediating maize drought stress tolerance.


Assuntos
Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Transcriptoma/genética , Transcriptoma/fisiologia , Zea mays/genética , Zea mays/fisiologia , Aminoácidos/genética , Aminoácidos/metabolismo , Vias Biossintéticas/genética , Vias Biossintéticas/fisiologia , Secas , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Homeostase/genética , Homeostase/fisiologia , Oxirredução , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plântula/genética , Plântula/fisiologia , Análise de Sequência de RNA/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Água/metabolismo
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