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1.
Circ Res ; 133(4): 333-349, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37462027

RESUMO

BACKGROUND: Lymphatic vessels are responsible for tissue drainage, and their malfunction is associated with chronic diseases. Lymph uptake occurs via specialized open cell-cell junctions between capillary lymphatic endothelial cells (LECs), whereas closed junctions in collecting LECs prevent lymph leakage. LEC junctions are known to dynamically remodel in development and disease, but how lymphatic permeability is regulated remains poorly understood. METHODS: We used various genetically engineered mouse models in combination with cellular, biochemical, and molecular biology approaches to elucidate the signaling pathways regulating junction morphology and function in lymphatic capillaries. RESULTS: By studying the permeability of intestinal lacteal capillaries to lipoprotein particles known as chylomicrons, we show that ROCK (Rho-associated kinase)-dependent cytoskeletal contractility is a fundamental mechanism of LEC permeability regulation. We show that chylomicron-derived lipids trigger neonatal lacteal junction opening via ROCK-dependent contraction of junction-anchored stress fibers. LEC-specific ROCK deletion abolished junction opening and plasma lipid uptake. Chylomicrons additionally inhibited VEGF (vascular endothelial growth factor)-A signaling. We show that VEGF-A antagonizes LEC junction opening via VEGFR (VEGF receptor) 2 and VEGFR3-dependent PI3K (phosphatidylinositol 3-kinase)/AKT (protein kinase B) activation of the small GTPase RAC1 (Rac family small GTPase 1), thereby restricting RhoA (Ras homolog family member A)/ROCK-mediated cytoskeleton contraction. CONCLUSIONS: Our results reveal that antagonistic inputs into ROCK-dependent cytoskeleton contractions regulate the interconversion of lymphatic junctions in the intestine and in other tissues, providing a tunable mechanism to control the lymphatic barrier.


Assuntos
Vasos Linfáticos , Proteínas Monoméricas de Ligação ao GTP , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Endoteliais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Quilomícrons/metabolismo , Vasos Linfáticos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Permeabilidade Capilar
2.
Biochem Biophys Res Commun ; 711: 149888, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38603833

RESUMO

OBJECTIVE: To investigate the effect of intermittent parathyroid hormone (iPTH) administration on pathological new bone formation during treatment of ankylosing spondylitis-related osteoporosis. METHODS: Animal models with pathological bone formation caused by hypothetical AS pathogenesis received treatment with iPTH. We determined the effects of iPTH on bone loss and the formation of pathological new bone with micro-computed tomography (micro-CT) and histological examination. In addition, the tamoxifen-inducible conditional knockout mice (CAGGCre-ERTM; PTHflox/flox, PTH-/-) was established to delete PTH and investigate the effect of endogenous PTH on pathological new bone formation. RESULTS: iPTH treatment significantly improved trabecular bone mass in the modified collagen-induced arthritis (m-CIA) model and unbalanced mechanical loading models. Meanwhile, iPTH treatment did not enhance pathological new bone formation in all types of animal models. Endogenous PTH deficiency had no effects on pathological new bone formation in unbalanced mechanical loading models. CONCLUSION: Experimental animal models of AS treated with iPTH show improvement in trabecular bone density, but not entheseal pathological bone formation,indicating it may be a potential treatment for inflammatory bone loss does in AS.


Assuntos
Osteogênese , Hormônio Paratireóideo , Animais , Hormônio Paratireóideo/administração & dosagem , Hormônio Paratireóideo/farmacologia , Hormônio Paratireóideo/uso terapêutico , Osteogênese/efeitos dos fármacos , Camundongos , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Camundongos Knockout , Masculino , Microtomografia por Raio-X , Espondilite Anquilosante/tratamento farmacológico , Espondilite Anquilosante/patologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Densidade Óssea/efeitos dos fármacos
3.
Opt Express ; 32(8): 13001-13013, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859282

RESUMO

The monitoring of hydrological elements in the polar region is the basis for the study of the dynamic environment under the ice. The traditional cross-season subglacial hydrological environment monitoring mainly relies on tether-type vertical profile measurement ice-based buoys, which have the advantages such as high reliability, high measurement accuracy, and real-time communication, while also has disadvantages of high-cost, large volume and weight, high power consumption, and complex layout. Therefore, it is urgent to develop a new type of ice-based profile buoy with low-cost, miniaturization, low power consumption, convenient deployment, and high reliability. In this paper, a novel optical fiber sensing scheme for ice-based buoy monitoring is proposed, which uses arrayed fiber grating to measure seawater temperature and depth profile and uses a dual-conduction mode resonance mechanism to measure seawater salinity. The temperature, depth, and salinity of seawater can be detected by an all-optical fiber technology in real-time. Preliminary experiments show that the temperature accuracy is ±0.1 °C in the range of -5∼35 °C, the salinity accuracy is ±0.03‰ in the range of 30‰âˆ¼40‰, and the vertical spatial resolution of depth can be adjusted in the range of 0∼1000 m, which can better meet the requirements of polar hydrological multi-layer profile observation. It can provide an innovative technology and equipment support for studying the spatiotemporal change process of the polar subglacial ocean.

4.
Ann Rheum Dis ; 82(4): 533-545, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36543525

RESUMO

OBJECTIVE: The aim of this study was to identify the role of Piezo1-mediated mechanotransduction in entheseal pathological new bone formation and to explore the underlying molecular mechanism. METHODS: Spinal ligament tissues were collected from 14 patients with ankylosing spondylitis (AS) and 14 non-AS controls and bulk RNA sequencing was conducted. Collagen antibody-induced arthritis models were established to observe pathological new bone formation. Pharmacological inhibition and genetic ablation of Piezo1 was performed in animal models to identify the essential role of Piezo1. Entheseal osteo-chondral lineage cells were collected and in vitro cell culture system was established to study the role and underlying mechanism of Piezo1 in regulation of chondrogenesis, osteogenesis and its own expression. RESULTS: Piezo1 was aberrantly upregulated in ligaments and entheseal tissues from patients with AS and animal models. Pharmaceutical and genetic inhibition of Piezo1 attenuated while activation of Piezo1 promoted pathological new bone formation. Mechanistically, activation of CaMKII (Calcium/calmodulin dependent protein kinase II) signalling was found essential for Piezo1-mediated mechanotransduction. In addition, Piezo1 was upregulated by AS-associated inflammatory cytokines. CONCLUSION: Piezo1-mediated mechanotransduction promotes entheseal pathological new bone formation through CaMKII signalling in AS.


Assuntos
Canais Iônicos , Mecanotransdução Celular , Ossificação Heterotópica , Espondilite Anquilosante , Animais , Humanos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Osteogênese/genética , Espondilite Anquilosante/genética , Espondilite Anquilosante/metabolismo , Canais Iônicos/metabolismo
5.
Circ Res ; 128(3): e27-e44, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33249995

RESUMO

RATIONALE: Defects in the morphogenesis of the fourth pharyngeal arch arteries (PAAs) give rise to lethal birth defects. Understanding genes and mechanisms regulating PAA formation will provide important insights into the etiology and treatments for congenital heart disease. OBJECTIVE: Cell-ECM (extracellular matrix) interactions play essential roles in the morphogenesis of PAAs and their derivatives, the aortic arch artery and its major branches; however, their specific functions are not well-understood. Previously, we demonstrated that integrin α5ß1 and Fn1 (fibronectin) expressed in the Isl1 lineages regulate PAA formation. The objective of the current studies was to investigate cellular mechanisms by which integrin α5ß1 and Fn1 regulate aortic arch artery morphogenesis. METHODS AND RESULTS: Using temporal lineage tracing, whole-mount confocal imaging, and quantitative analysis of the second heart field (SHF) and endothelial cell (EC) dynamics, we show that the majority of PAA EC progenitors arise by E7.5 in the SHF and contribute to pharyngeal arch endothelium between E7.5 and E9.5. Consequently, SHF-derived ECs in the pharyngeal arches form a plexus of small blood vessels, which remodels into the PAAs by 35 somites. The remodeling of the vascular plexus is orchestrated by signals dependent on the pharyngeal ECM microenvironment, extrinsic to the endothelium. Conditional ablation of integrin α5ß1 or Fn1 in the Isl1 lineages showed that signaling by the ECM regulates aortic arch artery morphogenesis at multiple steps: (1) accumulation of SHF-derived ECs in the pharyngeal arches, (2) remodeling of the EC plexus in the fourth arches into the PAAs, and (3) differentiation of neural crest-derived cells adjacent to the PAA endothelium into vascular smooth muscle cells. CONCLUSIONS: PAA formation is a multistep process entailing dynamic contribution of SHF-derived ECs to pharyngeal arches, the remodeling of endothelial plexus into the PAAs, and the remodeling of the PAAs into the aortic arch artery and its major branches. Cell-ECM interactions regulated by integrin α5ß1 and Fn1 play essential roles at each of these developmental stages.


Assuntos
Aorta Torácica/metabolismo , Junções Célula-Matriz/metabolismo , Células Progenitoras Endoteliais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Animais , Aorta Torácica/embriologia , Linhagem da Célula , Junções Célula-Matriz/genética , Matriz Extracelular/genética , Proteínas da Matriz Extracelular/genética , Fibronectinas/genética , Fibronectinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Integrina alfa5beta1/genética , Integrina alfa5beta1/metabolismo , Proteínas com Homeodomínio LIM/genética , Proteínas com Homeodomínio LIM/metabolismo , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Morfogênese , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Plant Dis ; 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37953231

RESUMO

Italian ryegrass is widely cultivated for the productions of forage, hay and silage, due to its high nutritional value and good palatability. Leaf spots caused by fungi pose a serious threat to forage crops. In order to expand knowledge of fungi causing leaf spot in ryegrass (Lolium multiforum) in Sichuan, Yunnan, Chongqing and Guizhou of southwestern China, a comprehensive survey was undertaken from 2015 to 2022. Survey discovered that Epicoccum leaf spot (ELS) was a common and widespread disease, more serious at the late stage of growth (after late May); symptomatic leaf samples collected from the four different provinces were analyzed, and a total of 202 Epicoccum isolates were obtained; based on both multilocus phylogeny (ITS, LSU, TUB2, and RPB2) and morphology, 10 Epicoccum species were finally identified, including three novel species (E. endololii sp. nov., E. lolii sp. nov. and E. loliicola sp. nov.), six new host records (E. draconis, E. endophyticum, E. oryzae, E. plurivorum, E. thailandicum and E. tobaicum), and an unknown species (Epicoccum sp.1). Pathogenicity tests showed that E. endophyticum, E. endololii and Epicoccum sp.1 were non-pathogenic to Italian ryegrass, which were confirmed as endophytes in this study; other six species could infect Italian ryegrass and cause leaf lesions to different degrees, of which E. draconis was more aggressive (P ≤ 0.05). Coupling with the isolation rates and geographical distributions of these species, E. plurivorum was the predominant pathogen in Yunnan while E. oryzae and E. tobaicum in other three provinces. This work provides an initial understanding of the taxonomies, virulence and distributions of Epicoccum species associated with ELS of southwestern China, and lays a solid foundation for the diagnosis in the field, and scientific control of ELS on Italian ryegrass.

7.
Sensors (Basel) ; 23(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37420774

RESUMO

Lithium-ion batteries are widely used in a variety of fields due to their high energy density, high power density, long service life, and environmental friendliness. However, safety accidents with lithium-ion batteries occur frequently. The real-time safety monitoring of lithium-ion batteries is particularly important during their use. The fiber Bragg grating (FBG) sensors have some additional advantages over conventional electrochemical sensors, such as low invasiveness, electromagnetic anti-interference, and insulating properties. This paper reviews lithium-ion battery safety monitoring based on FBG sensors. The principles and sensing performance of FBG sensors are described. The single-parameter monitoring and dual-parameter monitoring of lithium-ion batteries based on FBG sensors are reviewed. The current application state of the monitored data in lithium-ion batteries is summarized. We also present a brief overview of the recent developments in FBG sensors used in lithium-ion batteries. Finally, we discuss future trends in lithium-ion battery safety monitoring based on FBG sensors.


Assuntos
Fontes de Energia Elétrica , Lítio , Lítio/química , Íons
8.
Cell Biol Int ; 46(3): 359-369, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34865263

RESUMO

The enzyme m6 A methyltransferase-like 3 (METTL3) catalyzes N6 -methyladenosine (m6 A) modification in eukaryotic messenger RNAs (mRNAs). However, the physiological function and molecular mechanism of METTL3 in mammalian cells have not been fully understood. Here we showed that METTL3 was highly expressed in mouse mammary gland of the lactation period. METTL3 was located in the nucleus of bovine mammary epithelial cells (MECs), and methionine (Met) and ß-estrodial (E2) upregulated METTL3 protein level. METTL3 knockdown decreased milk protein and fat synthesis, whereas its overexpression had the opposite effects. METTL3 overexpression stimulated mRNA expression and protein phosphorylation of the mechanistic target of rapamycin (mTOR) and mRNA and protein expression of sterol regulatory element binding protein 1 (SREBP1), whereas METTL3 knockdown blocked the stimulatory effects of Met and E2 on these processes. Furthermore, METTL3 overexpression led to increased mRNA m6 A methylation of mTOR and SREBP1, whereas METTL3 knockdown suppressed the stimulatory effects of Met and E2 on these processes. The interaction between METTL3 and glycyl-tRNA synthetase (GlyRS) was confirmed by Co-immunoprecipitation and fluorescence resonance energy transfer approaches, and colocalization observation further showed that Met and E2 treatment increased this interaction. GlyRS knockdown abolished METTL3 protein levels upregulated by Met and E2, and METTL3 knockdown markedly decreased the effects of GlyRS overexpression on mTOR expression and phosphorylation and SREBP1 expression. In summary, we demonstrate that METTL3 is a key positive regulator of Met and E2-stimulated and GlyRS-mediated mTOR and SREBP1 signaling pathways and milk protein and fat synthesis in mammary epithelial cells.


Assuntos
Glândulas Mamárias Animais , Leite , Animais , Bovinos , Células Epiteliais/metabolismo , Feminino , Lactação , Mamíferos/metabolismo , Glândulas Mamárias Animais/metabolismo , Metiltransferases/metabolismo , Camundongos , Leite/metabolismo , Transdução de Sinais
9.
Bioorg Chem ; 123: 105768, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35378372

RESUMO

Cat eye syndrome chromosome region candidate 2 (CECR2) bromodomain is a module of CECR2-containing remodeling factor (CERF), which is a chromatin remodeling complex correlating with transcriptional control and adjustment of chromatin architecture. Potent chemical probes would be beneficial to gain insights into the biochemical and pharmacological functions of CECR2 BRD. Herein, we report the discovery of a series of CECR2 BRD inhibitors with 7H-pyrrolo[2,3-d] pyrimidine scaffold based on molecular docking model of TP-248 and CECR2 BRD. The most potent inhibitor of this series, DC-CBi-22 with IC50 of 8.0 ± 1.4 nM against CECR2 BRD and selectivity over BPTF BRD up to 24.9-fold. The SARs were detailed according to molecular docking. DC-CBi-22 would serve as a useful chemical probe for the study of CECR2.


Assuntos
Pirimidinas , Fatores de Transcrição , Simulação de Acoplamento Molecular , Domínios Proteicos , Pirimidinas/farmacologia , Relação Estrutura-Atividade , Fatores de Transcrição/química
10.
J Nanobiotechnology ; 20(1): 389, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042499

RESUMO

Dysregulated mucosal immune responses and colonic fibrosis impose two formidable challenges for ulcerative colitis treatment. It indicates that monotherapy could not sufficiently deal with this complicated disease and combination therapy may provide a potential solution. A chitosan-modified poly(lactic-co-glycolic acid) nanoparticle (CS-PLGA NP) system was developed for co-delivering patchouli alcohol and simvastatin to the inflamed colonic epithelium to alleviate the symptoms of ulcerative colitis via remodeling immune microenvironment and anti-fibrosis, a so-called "two-birds-one-stone" nanotherapeutic strategy. The bioadhesive nanomedicine enhanced the intestinal epithelial cell uptake efficiency and improved the drug stability in the gastrointestinal tract. The nanomedicine effectively regulated the Akt/MAPK/NF-κB pathway and reshaped the immune microenvironment through repolarizing M2Φ, promoting regulatory T cells and G-MDSC, suppressing neutrophil and inflammatory monocyte infiltration, as well as inhibiting dendritic cell maturation. Additionally, the nanomedicine alleviated colonic fibrosis. Our work elucidates that the colon-targeted codelivery for combination therapy is promising for ulcerative colitis treatment and to address the unmet medical need.


Assuntos
Colite Ulcerativa , Colite , Nanopartículas , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colo/metabolismo , Humanos , Nanomedicina
11.
Dev Biol ; 458(1): 88-97, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669335

RESUMO

Atrioventricular valve development requires endothelial-to-mesenchymal transition (EndMT) that induces cushion endocardial cells to give rise to mesenchymal cells crucial to valve formation. In the adult endothelium, deletion of the docking protein FRS2α induces EndMT by activating TGFß signaling in a miRNA let-7-dependent manner. To study the role of endothelial FRS2α during embryonic development, we generated mice with an inducible endothelial-specific deletion of Frs2α (FRS2αiECKO). Analysis of the FRS2αiECKO embryos uncovered a combination of impaired EndMT in AV cushions and defective maturation of AV valves leading to development of thickened, abnormal valves when Frs2α was deleted early (E7.5) in development. At the same time, no AV valve developmental abnormalities were observed after late (E10.5) deletion. These observations identify FRS2α as a pivotal controller of cell fate transition during both EndMT and post-EndMT valvulogenesis.


Assuntos
Coxins Endocárdicos/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Membrana/fisiologia , Animais , Contagem de Células , Linhagem da Célula , Comunicação Atrioventricular/embriologia , Comunicação Atrioventricular/genética , Coxins Endocárdicos/citologia , Coxins Endocárdicos/patologia , Células Endoteliais/citologia , Deleção de Genes , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Mesoderma/citologia , Mesoderma/embriologia , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/fisiologia , Valva Mitral/anormalidades , Valva Mitral/embriologia , Morfogênese/genética , Fenótipo , Valva Tricúspide/anormalidades , Valva Tricúspide/embriologia
12.
Ann Rheum Dis ; 80(7): 891-902, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33858850

RESUMO

OBJECTIVES: The aim of this study was to identify the role of tenascin-C (TNC) in entheseal new bone formation and to explore the underlying molecular mechanism. METHODS: Ligament tissue samples were obtained from patients with ankylosing spondylitis (AS) during surgery. Collagen antibody-induced arthritis and DBA/1 models were established to observe entheseal new bone formation. TNC expression was determined by immunohistochemistry staining. Systemic inhibition or genetic ablation of TNC was performed in animal models. Mechanical properties of extracellular matrix (ECM) were measured by atomic force microscopy. Downstream pathway of TNC was analysed by RNA sequencing and confirmed with pharmacological modulation both in vitro and in vivo. Cellular source of TNC was analysed by single-cell RNA sequencing (scRNA-seq) and confirmed by immunofluorescence staining. RESULTS: TNC was aberrantly upregulated in ligament and entheseal tissues from patients with AS and animal models. TNC inhibition significantly suppressed entheseal new bone formation. Functional assays revealed that TNC promoted new bone formation by enhancing chondrogenic differentiation during endochondral ossification. Mechanistically, TNC suppressed the adhesion force of ECM, resulting in the activation of downstream Hippo/yes-associated protein signalling, which in turn increased the expression of chondrogenic genes. scRNA-seq and immunofluorescence staining further revealed that TNC was majorly secreted by fibroblast-specific protein-1 (FSP1)+fibroblasts in the entheseal inflammatory microenvironment. CONCLUSION: Inflammation-induced aberrant expression of TNC by FSP1+fibroblasts promotes entheseal new bone formation by suppressing ECM adhesion forces and activating Hippo signalling.


Assuntos
Matriz Extracelular/patologia , Ossificação Heterotópica/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Espondilite Anquilosante/metabolismo , Tenascina/metabolismo , Animais , Artrite Experimental , Via de Sinalização Hippo , Humanos , Camundongos , Ossificação Heterotópica/patologia , Transdução de Sinais/fisiologia , Espondilite Anquilosante/patologia
13.
Analyst ; 145(2): 550-556, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31764924

RESUMO

d-Luciferin is a popular bioluminescent substrate of luciferase in the presence of ATP. It is used in luciferase-based bioluminescence imaging and cell-based high-throughput screening applications. Herein, the iodination of d-luciferin was undertaken and explored as a bioluminescence probe without the need for light excitation to sensitively trace and image carbon monoxide (CO) in liver cancer cells. The bioluminescent probe (7'-iodo-luciferin) exhibited excellent selectivity for CO detection in vitro. This new probe could image exogenous and endogenous CO in the luciferase-transfected cancer cells. This new probe might be used for evaluating the roles of CO in various biological processes.


Assuntos
Monóxido de Carbono/análise , Luciferina de Vaga-Lumes/análogos & derivados , Substâncias Luminescentes/química , Linhagem Celular Tumoral , Luciferina de Vaga-Lumes/síntese química , Luciferina de Vaga-Lumes/toxicidade , Células HEK293 , Halogenação , Humanos , Limite de Detecção , Luciferases de Vaga-Lume/química , Luminescência , Substâncias Luminescentes/síntese química , Substâncias Luminescentes/toxicidade , Medições Luminescentes/métodos , Compostos Organometálicos/química
14.
J Cell Physiol ; 234(5): 7608-7621, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30471104

RESUMO

Amino acids are required for the activation of mammalian target of rapamycin (mTOR) to increase cell growth, protein and lipid synthesis, and inhibit autophagy. However, the mechanism through which amino acids activate the mTOR signaling is still largely unknown. In our previous study, we discovered that glycyl-tRNA synthetase (GlyRS) is a key mediator of amino-acid-induced mTOR expression and activation in bovine mammary epithelial cells (BMECs). Here we show that amino acids stimulate GlyRS nuclear localization for mTOR expression in BMECs. Met stimulates GlyRS nuclear localization, and the nuclear GlyRS is cleaved into a C-terminus-containing truncated form. We prove that GlyRS has a bipartite nuclear leading sequences, and GlyRS is phosphorylated at Thr544 and Ser704 in the cytoplasm under the stimulation of amino acids (Met, Leu, and Lys). The nuclear GlyRS physically binds to nuclear factor kappa B1, triggers its phosphorylation, thereby enhancing mRNA expression of its target genes including mTOR, S6K1, and 4EBP1. We further demonstrate that GlyRS is required for the inhibition of autophagy by Met. Thus our work elucidates that amino acids trigger GlyRS phosphorylation and nuclear localization to enhance the mRNA expression of mTOR.


Assuntos
Aminoácidos/metabolismo , Células Epiteliais/metabolismo , Glicina-tRNA Ligase/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia/fisiologia , Bovinos , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Glândulas Mamárias Animais/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia
15.
Foodborne Pathog Dis ; 16(5): 331-338, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30676080

RESUMO

Increasing clinical significance of coagulase-negative staphylococci requires effective methods for species identification and genotyping. In this study, six housekeeping genes (femA, ftsZ, gap, pyrH, rpoB, and tuf) with extensive allelic polymorphisms were identified and evaluated to develop a comprehensive multilocus sequence typing (MLST) scheme. Selected primers were capable of amplification of the six loci from all of the 180 Staphylococcus strains belonging to 18 different species. Sequence analysis of each locus (44-63 alleles) revealed higher nucleotide diversity than 16S rRNA (28 alleles). Phylogenetic analysis of the concatenated sequences (3054 bp) of the six loci provided accurate species identification and highly discriminatory typing for all the strains. Multilocus allelic analysis of the 180 Staphylococcus strains generated 103 different sequence profiles, suggesting high genetic diversity of the strains. For example, 30 S. aureus, 37 S. epidermidis, 32 S. haemolyticus, and 14 S. hominis strains were typed into 15, 21, 11, and 10 sequence profiles, respectively. Compared with published MLST schemes that restrict on a few particular species, this new scheme both achieved similar discrimination for typing S. aureus, S. epidermidis, S. haemolyticus, and S. hominis and provided sufficient discriminatory power for typing additional opportunistic species, such as S. cohnii, S. capitis, and S. warneri. Importantly, the comprehensive MLST scheme for Staphylococcus strains provides a better genotyping tool for understanding the phylogeny of coagulase-positive Staphylococcus aureus strains.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Tipagem de Sequências Multilocus/métodos , RNA Ribossômico 16S/genética , Staphylococcus/classificação , Proteínas de Bactérias/genética , Coagulase/genética , Genótipo , Filogenia , Staphylococcus/isolamento & purificação , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação
16.
Dev Biol ; 421(2): 108-117, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27955943

RESUMO

Oxygenated blood from the heart is directed into the systemic circulation through the aortic arch arteries (AAAs). The AAAs arise by remodeling of three symmetrical pairs of pharyngeal arch arteries (PAAs), which connect the heart with the paired dorsal aortae at mid-gestation. Aberrant PAA formation results in defects frequently observed in patients with lethal congenital heart disease. How the PAAs form in mammals is not understood. The work presented in this manuscript shows that the second heart field (SHF) is the major source of progenitors giving rise to the endothelium of the pharyngeal arches 3 - 6, while the endothelium in the pharyngeal arches 1 and 2 is derived from a different source. During the formation of the PAAs 3 - 6, endothelial progenitors in the SHF extend cellular processes toward the pharyngeal endoderm, migrate from the SHF and assemble into a uniform vascular plexus. This plexus then undergoes remodeling, whereby plexus endothelial cells coalesce into a large PAA in each pharyngeal arch. Taken together, our studies establish a platform for investigating cellular and molecular mechanisms regulating PAA formation and alterations that lead to disease.


Assuntos
Região Branquial/embriologia , Endotélio/embriologia , Coração/embriologia , Animais , Aorta/embriologia , Região Branquial/citologia , Sobrevivência Celular , Embrião de Mamíferos/metabolismo , Células Endoteliais/metabolismo , Endotélio/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Camundongos Transgênicos , Células-Tronco/citologia , Fatores de Tempo
17.
J Cell Physiol ; 233(3): 2464-2475, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28771726

RESUMO

Annexin A2 (AnxA2) has been shown to play multiple roles in growth, development, and metabolism, but the functions of AnxA2 and the signaling pathways associated with AnxA2 are still not fully understood. In this study, we aim to reveal whether and how AnxA2 could be involved in milk synthesis and proliferation of bovine mammary epithelial cells (BMECs). Using gene function study approaches, we found that AnxA2 positively regulates PIP3 level, phosphorylation of mTOR, and protein levels of SREBP-1c and Cyclin D1 leading to milk synthesis and cell proliferation. We further observed that both AnxA2-36 kD phosphorylated form and AnxA2-33 kD protein could be induced from AnxA2-36 kD protein in BMECs under methionine, leucine, estrogen or prolactin stimulation. These above results strongly demonstrate that AnxA2 functions as a critical regulator for amino acid or hormone-induced milk synthesis and cell proliferation via the PI3K-mTOR-SREBP-1c/Cyclin D1 signaling pathway.


Assuntos
Anexina A2/metabolismo , Proliferação de Células , Células Epiteliais/enzimologia , Glândulas Mamárias Humanas/enzimologia , Proteínas do Leite/biossíntese , Serina-Treonina Quinases TOR/metabolismo , Animais , Anexina A2/genética , Bovinos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ciclina D1/metabolismo , Células Epiteliais/efeitos dos fármacos , Estrogênios/farmacologia , Feminino , Humanos , Leucina/farmacologia , Glândulas Mamárias Humanas/efeitos dos fármacos , Metionina/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação , Progesterona/farmacologia , Interferência de RNA , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Transfecção
18.
Cell Biol Int ; 42(5): 533-542, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29286187

RESUMO

ATPase family AAA-domain containing protein 3A (ATAD3A) is a nuclear-encoded mitochondrial membrane protein, which is essential for cell growth and metabolism. The mechanism by which ATAD3A acts is still not fully understood. In this study, we explored the regulatory role of ATAD3A on milk biosynthesis and proliferation of bovine mammary epithelial cell. We showed that ATAD3A is localized in mitochondria and the expression of ATAD3A was up-regulated in response to extracellular stimuli such as amino acids and hormones. We observed that ATAD3A positively regulated milk protein, fat, and lactose biosynthesis, and cell proliferation. We further revealed that ATAD3A promoted the expressions of mTOR, SREBP-1c, and Cyclin D1, and triggers mTOR phosphorylation. In summary, our data reveal that ATAD3A regulates the mTOR, SREBP-1c, and Cyclin D1 signaling pathways for milk biosynthesis and cell proliferation.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Bovinos/metabolismo , Glândulas Mamárias Animais/enzimologia , Proteínas de Membrana/metabolismo , Leite/metabolismo , Proteínas Mitocondriais/metabolismo , Serina-Treonina Quinases TOR/metabolismo , ATPases Associadas a Diversas Atividades Celulares/fisiologia , Aminoácidos/fisiologia , Animais , Proliferação de Células , Células Cultivadas , Indústria de Laticínios , Células Epiteliais/enzimologia , Feminino , Hormônios/fisiologia , Proteínas de Membrana/fisiologia , Proteínas Mitocondriais/fisiologia , Transdução de Sinais
19.
Clin Exp Rheumatol ; 36(5): 871-878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29652653

RESUMO

OBJECTIVES: To investigate the foetal outcomes and examine the predictive value of the third-trimester umbilical artery Doppler in systemic lupus erythematosus (SLE) pregnancies. METHODS: Data of 180 pregnancies in 175 SLE patients from Jan 2007 to Jan 2017 were analysed retrospectively. Pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio (S/D) of the umbilical artery flow velocity data were monitored by Doppler ultrasound. RESULTS: One or more composite adverse pregnancy outcomes (APOs) occurred in 46.7% of patients with SLE. A total of 62 (34.4%) pregnancies were pre-term birth, and 34 (18.9%) newborns were small for gestational age (SGA). Twenty-two of pregnancies (12.2%) resulted in foetal distress. In multivariate analysis, predictors of composite APOs included positive anti-Ro (OR 5.5, 95% CI 1.7-18.2, p=0.005) and low complement (OR 3.9, 95% CI 1.1-13.6, p=0.04). Doppler PI, RI, and S/D were significantly higher in the pre-term birth, SGA, and composite APO groups than in the patients without APOs. RI with cut-off values of 0.57 and 0.70 indicated the highest risk of pre-term birth and composite APOs, with sensitivities of 50.0% and 21.4%, as well as specificities of 59.6% and 97.7%, respectively. PI emerged as the best predictor of SGA. The optimal cutoff value for PI was 0.77, at which sensitivity (90.9%) and specificity (49.2%) had the best combination. CONCLUSIONS: Pregnancies in lupus still had an increased risk of APOs in terms of pre-term birth. Third-trimester umbilical artery Doppler was useful in predicting pre-term birth, SGA, and composite APOs in lupus pregnancies.


Assuntos
Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Complicações na Gravidez/diagnóstico por imagem , Ultrassonografia Doppler , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/fisiopatologia , Valor Preditivo dos Testes , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/fisiopatologia , Resultado da Gravidez , Terceiro Trimestre da Gravidez , Fluxo Pulsátil , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Artérias Umbilicais/fisiopatologia , Adulto Jovem
20.
Clin Exp Rheumatol ; 36(5): 884-890, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29652659

RESUMO

OBJECTIVES: To evaluate the efficacy of different tapering or discontinuation strategies of etanercept in a cohort of axial spondyloarthritis from South China. METHODS: We performed a retrospective cohort study. Axial SpA patients who achieved clinical remission for at least 6 months after receiving a standard dose of etanercept therapy were enrolled. Different tapering or discontinuation strategies were compared. RESULTS: Altogether, 258 cases were enrolled. No differences were found in baseline characteristics among the three groups. Significantly more patients on discontinuation group (19%) than tapering group (5.4%, p<0.001) relapsed as early as 6 months. Almost all of the patients (103/107, 96.3%) in taper 25% group and more than 80% (71/88, 80.7%) of the patients in taper 50% group maintained low disease activity (LDA) or clinical remission during the first year. At the end of the 2-year follow-up, the percentage of patients maintaining LDA or remission were 28.6% (discontinuation), 55.7% (taper 50%), 84.1% (taper 25%), respectively. Activity indexes were significantly lower in taper 25% group compared to the other two groups. Patients in discontinuation group and tapering 50% group, with longer SpA duration were more likely to relapse, and remission>12 months before discontinuation/tapering helped to reduce relapse. CONCLUSIONS: It is feasible to slowly increase the dosing interval and transit to the lowest effective dosing interval for some patients in remission/LDA. Prolonging the time under remission before tapering help to improve the outcome. Tapering 25% of the etanercept dose every 3 months may be a pragmatic approach for more cost-effective use of the drug.


Assuntos
Antirreumáticos/administração & dosagem , Etanercepte/administração & dosagem , Articulações/efeitos dos fármacos , Coluna Vertebral/efeitos dos fármacos , Espondilite Anquilosante/tratamento farmacológico , Adulto , Tomada de Decisão Clínica , Esquema de Medicação , Feminino , Humanos , Articulações/imunologia , Articulações/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Estudos Retrospectivos , Coluna Vertebral/imunologia , Coluna Vertebral/fisiopatologia , Espondilite Anquilosante/diagnóstico , Espondilite Anquilosante/imunologia , Espondilite Anquilosante/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia , Adulto Jovem
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