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1.
Nature ; 625(7996): 768-777, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38200313

RESUMO

Cerebrospinal fluid (CSF) in the subarachnoid space around the brain has long been known to drain through the lymphatics to cervical lymph nodes1-17, but the connections and regulation have been challenging to identify. Here, using fluorescent CSF tracers in Prox1-GFP lymphatic reporter mice18, we found that the nasopharyngeal lymphatic plexus is a major hub for CSF outflow to deep cervical lymph nodes. This plexus had unusual valves and short lymphangions but no smooth-muscle coverage, whereas downstream deep cervical lymphatics had typical semilunar valves, long lymphangions and smooth muscle coverage that transported CSF to the deep cervical lymph nodes. α-Adrenergic and nitric oxide signalling in the smooth muscle cells regulated CSF drainage through the transport properties of deep cervical lymphatics. During ageing, the nasopharyngeal lymphatic plexus atrophied, but deep cervical lymphatics were not similarly altered, and CSF outflow could still be increased by adrenergic or nitric oxide signalling. Single-cell analysis of gene expression in lymphatic endothelial cells of the nasopharyngeal plexus of aged mice revealed increased type I interferon signalling and other inflammatory cytokines. The importance of evidence for the nasopharyngeal lymphatic plexus functioning as a CSF outflow hub is highlighted by its regression during ageing. Yet, the ageing-resistant pharmacological activation of deep cervical lymphatic transport towards lymph nodes can still increase CSF outflow, offering an approach for augmenting CSF clearance in age-related neurological conditions in which greater efflux would be beneficial.


Assuntos
Líquido Cefalorraquidiano , Vértebras Cervicais , Drenagem , Vasos Linfáticos , Animais , Camundongos , Envelhecimento/metabolismo , Líquido Cefalorraquidiano/metabolismo , Vértebras Cervicais/metabolismo , Células Endoteliais/metabolismo , Fluorescência , Genes Reporter , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Vasos Linfáticos/fisiologia , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Nariz/fisiologia , Faringe/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Análise de Célula Única , Transdução de Sinais
2.
Sci Immunol ; 8(88): eadg6155, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37801517

RESUMO

High neonatal susceptibility to meningitis has been attributed to the anatomical barriers that act to protect the central nervous system (CNS) from infection being immature and not fully developed. However, the mechanisms by which pathogens breach CNS barriers are poorly understood. Using the Armstrong strain of lymphocytic choriomeningitis virus (LCMV) to study virus propagation into the CNS during systemic infection, we demonstrate that mortality in neonatal, but not adult, mice is high after infection. Virus propagated extensively from the perivenous sinus region of the dura mater to the leptomeninges, choroid plexus, and cerebral cortex. Although the structural barrier of CNS border tissues is comparable between neonates and adults, immunofluorescence staining and single-cell RNA sequencing analyses revealed that the neonatal dural immune cells are immature and predominantly composed of CD206hi macrophages, with major histocompatibility complex class II (MHCII)hi macrophages being rare. In adults, however, perivenous sinus immune cells were enriched in MHCIIhi macrophages that are specialized for producing antiviral molecules and chemokines compared with CD206hi macrophages and protected the CNS against systemic virus invasion. Our findings clarify how systemic pathogens enter the CNS through its border tissues and how the immune barrier at the perivenous sinus region of the dura blocks pathogen access to the CNS.


Assuntos
Encefalite Viral , Coriomeningite Linfocítica , Meningite Viral , Meningoencefalite , Camundongos , Animais , Sistema Nervoso Central , Meninges , Vírus da Coriomeningite Linfocítica
3.
Nat Commun ; 14(1): 2754, 2023 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-37179330

RESUMO

Active thermogenesis in the brown adipose tissue (BAT) facilitating the utilization of lipids and glucose is critical for maintaining body temperature and reducing metabolic diseases, whereas inactive BAT accumulates lipids in brown adipocytes (BAs), leading to BAT whitening. Although cellular crosstalk between endothelial cells (ECs) and adipocytes is essential for the transport and utilization of fatty acid in BAs, the angiocrine roles of ECs mediating this crosstalk remain poorly understood. Using single-nucleus RNA sequencing and knock-out male mice, we demonstrate that stem cell factor (SCF) derived from ECs upregulates gene expressions and protein levels of the enzymes for de novo lipogenesis, and promotes lipid accumulation by activating c-Kit in BAs. In the early phase of lipid accumulation induced by denervation or thermoneutrality, transiently expressed c-Kit on BAs increases the protein levels of the lipogenic enzymes via PI3K and AKT signaling. EC-specific SCF deletion and BA-specific c-Kit deletion attenuate the induction of the lipogenic enzymes and suppress the enlargement of lipid droplets in BAs after denervation or thermoneutrality in male mice. These data provide insight into SCF/c-Kit signaling as a regulator that promotes lipid accumulation through the increase of lipogenic enzymes in BAT when thermogenesis is inhibited.


Assuntos
Adipócitos Marrons , Hipercolesterolemia , Animais , Masculino , Camundongos , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/metabolismo , Células Endoteliais/metabolismo , Ácidos Graxos/metabolismo , Hipercolesterolemia/metabolismo , Lipogênese/genética , Camundongos Knockout , Receptores Proteína Tirosina Quinases/metabolismo , Fator de Células-Tronco/genética , Fator de Células-Tronco/metabolismo , Termogênese/genética , Proteínas Proto-Oncogênicas c-kit
4.
J Am Soc Nephrol ; 34(5): 809-828, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724799

RESUMO

SIGNIFICANCE STATEMENT: Mesangial cells (MCs) in the kidney are essential to maintaining glomerular integrity, and their impairment leads to major glomerular diseases including diabetic nephropathy (DN). Although high blood glucose elicits abnormal alterations in MCs, the underlying mechanism is poorly understood. We show that YAP/TAZ are increased in MCs of patients with DN and two animal models of DN. High glucose directly induces activation of YAP/TAZ through the canonical Hippo pathway in cultured MCs. Hyperactivation of YAP/TAZ in mouse MCs recapitulates the hallmarks of DN. Activated YAP/TAZ bind and stabilize N-Myc, one of the Myc family. N-Myc stabilization leads to aberrant enhancement of its transcriptional activity and to MC impairments. Our findings shed light on how high blood glucose in diabetes mellitus leads to DN and support a rationale that lowering blood glucose in diabetes mellitus could delay DN pathogenesis. BACKGROUND: Mesangial cells (MCs) in the kidney are central to maintaining glomerular integrity, and their impairment leads to major glomerular diseases, including diabetic nephropathy (DN). Although high blood glucose elicits abnormal alterations in MCs, the underlying molecular mechanism is poorly understood. METHODS: Immunolocalization of YAP/TAZ and pathological features of PDGFRß + MCs were analyzed in the glomeruli of patients with DN, in Zucker diabetic fatty rats, and in Lats1/2i ΔPß mice. RiboTag bulk-RNA sequencing and transcriptomic analysis of gene expression profiles of the isolated MCs from control and Lats1/2iΔPß mice were performed. Immunoprecipitation analysis and protein stability of N-Myc were performed by the standard protocols. RESULTS: YAP and TAZ, the final effectors of the Hippo pathway, are highly increased in MCs of patients with DN and in Zucker diabetic fatty rats. Moreover, high glucose directly induces activation of YAP/TAZ through the canonical Hippo pathway in cultured MCs. Hyperactivation of YAP/TAZ in mouse model MCs recapitulates the hallmarks of DN, including excessive proliferation of MCs and extracellular matrix deposition, endothelial cell impairment, glomerular sclerosis, albuminuria, and reduced glomerular filtration rate. Mechanistically, activated YAP/TAZ bind and stabilize N-Myc protein, one of the Myc family of oncogenes. N-Myc stabilization leads to aberrant enhancement of its transcriptional activity and eventually to MC impairments and DN pathogenesis. CONCLUSIONS: Our findings shed light on how high blood glucose in diabetes mellitus leads to DN and support a rationale that lowering blood glucose in diabetes mellitus could delay DN pathogenesis.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Ratos , Camundongos , Animais , Células Mesangiais/metabolismo , Nefropatias Diabéticas/metabolismo , Glicemia/metabolismo , Ratos Zucker , Proteínas Serina-Treonina Quinases/metabolismo
5.
Mol Ther ; 31(4): 1002-1016, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36755495

RESUMO

Fabry disease (FD), a lysosomal storage disorder, is caused by defective α-galactosidase (GLA) activity, which results in the accumulation of globotriaosylceramide (Gb3) in endothelial cells and leads to life-threatening complications such as left ventricular hypertrophy (LVH), renal failure, and stroke. Enzyme replacement therapy (ERT) results in Gb3 clearance; however, because of a short half-life in the body and the high immunogenicity of FD patients, ERT has a limited therapeutic effect, particularly in patients with late-onset disease or progressive complications. Because vascular endothelial cells (VECs) derived from FD-induced pluripotent stem cells display increased thrombospondin-1 (TSP1) expression and enhanced SMAD2 signaling, we screened for chemical compounds that could downregulate TSP1 and SMAD2 signaling. Fasudil reduced the levels of p-SMAD2 and TSP1 in FD-VECs and increased the expression of angiogenic factors. Furthermore, fasudil downregulated the endothelial-to-mesenchymal transition (EndMT) and mitochondrial function of FD-VECs. Oral administration of fasudil to FD mice alleviated several FD phenotypes, including LVH, renal fibrosis, anhidrosis, and heat insensitivity. Our findings demonstrate that fasudil is a novel candidate for FD therapy.


Assuntos
Doença de Fabry , Animais , Camundongos , Doença de Fabry/tratamento farmacológico , Doença de Fabry/genética , Células Endoteliais/metabolismo , alfa-Galactosidase/genética , Fenótipo , Terapia de Reposição de Enzimas
6.
Heliyon ; 9(1): e12684, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685467

RESUMO

We developed a method combining ultraviolet (UV) detection and integrated pulsed amperometric detection (IPAD) to simultaneously analyze eleutheroside B, eleutheroside E, chiisanoside, and sesamin. The gradient elution system allowed complete separation of all target components within 35 min, and showed limits of detection of 0.006-0.020 µg/mL and limits of quantification of 0.018-0.050 µg/mL. The linear regression coefficients of determination were 0.9990-0.9998. All inter- and intra-day precision values were below 4.89%, and the average recoveries were 97.79-104.40%. The developed approach exhibits excellent reproducibility, sensitivity, and selectivity without requiring any complicated pre-treatment, and is therefore expected to be helpful as a tool for establishing appropriate content criteria for Acanthopanax species.

7.
Front Pharmacol ; 13: 903664, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784731

RESUMO

Loss of dopamine (DA) is one of the primary features of Parkinson's disease (PD); however, imbalances of non-dopaminergic neurotransmitters significantly contribute to the disabilities noted in advanced PD patients. DA-9805 is the ethanolic extraction of the root bark of Paeonia × suffruticosa Andrews (Paeoniaceae), the root of Angelica dahurica (Hoffm.) Benth. and Hook.f. ex Franch. and Sav. (Apiaceae) and the root of Bupleurum falcatum L. (Apiaceae), which have been widely utilized as an enhancer of motor function in East Asia. This study aimed to investigate whether DA-9805 modified motor dysfunctions and imbalances associated with DA and other neurotransmitters in a 6-hydroxydopamine-induced PD mouse. We confirmed the expressions of proteins related with neurotransmissions in the striatum. In addition, we measured the striatal neurotransmitters using HPLC and analyzed their correlation. DA-9805 significantly improved motor impairments and restored the altered levels of neurotransmitters in the striatum. Moreover, DA-9805 improved the altered expressions of tyrosine hydroxylase (TH), DA transporter, and choline acetyltransferase (ChAT) in the ipsilateral part of mouse striatum or SNpc, which implies the neuroprotection. We also found that the level of striatal acetylcholine (Ach) has the moderate negative correlation with motor functions and TH expression in the SNpc. This study indicates that DA-9805 restores motor dysfunctions by normalizing the increased levels of striatal Ach via modulating DA transmission and ChAT expressions as well as its neuroprotective effects.

8.
Anal Chem ; 94(28): 10127-10134, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35802862

RESUMO

To achieve the measurement reliability of amino acids used as diagnostic markers in clinical fields, establishing a reference measurement system is required, in which certified reference materials (CRMs) are an essential step in the hierarchy of measurement traceability. This study describes the development of dried blood spot (DBS) CRMs for amino acid analysis with complete measurement traceability to the International System of Units (SI). Six essential amino acids─proline, valine, isoleucine, leucine, phenylalanine, and tyrosine─were analyzed using isotope-dilution liquid chromatography-mass spectrometry (ID-MS). For minimizing measurement bias and uncertainty overestimation, whole spots with 50 µL of whole blood were adopted in the certification. The between-spot homogeneities by whole spot sampling were lower than 2.1%. The relative expanded uncertainties of the six amino acids in the developed DBS CRMs were lower than 5.7% at 95% confidence. The certified values are traceable to SI through both gravimetric preparation and the primary method in certification, ID-MS. Comparison among DBS testing laboratories revealed discrepancies between the whole spot and disc sampling methods. The actual sampling volume was accurately estimated by weighing, which revealed the possibility of underestimation in routine DBS testing. The candidate CRMs can support the standardization of DBS testing for amino acids through the qualification and validation of many kinds of measurement procedures to compensate the measurement bias caused by matrix-specific sampling error.


Assuntos
Aminoácidos , Teste em Amostras de Sangue Seco , Aminoácidos/análise , Certificação , Cromatografia Líquida/métodos , Padrões de Referência , Reprodutibilidade dos Testes
9.
Sci Adv ; 8(23): eabn2611, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35687678

RESUMO

In sprouting angiogenesis, the precise mechanisms underlying how intracellular vascular endothelial growth factor receptor 2 (VEGFR2) signaling is higher in one endothelial cell (EC) compared with its neighbor and acquires the tip EC phenotype under a similar external cue are elusive. Here, we show that Merlin, encoded by the neurofibromatosis type 2 (NF2) gene, suppresses VEGFR2 internalization depending on VE-cadherin density and inhibits tip EC induction. Accordingly, endothelial Nf2 depletion promotes tip EC induction with excessive filopodia by enhancing VEGFR2 internalization in both the growing and matured vessels. Mechanistically, Merlin binds to the VEGFR2-VE-cadherin complex at cell-cell junctions and reduces VEGFR2 internalization-induced downstream signaling during tip EC induction. As a consequence, nonfunctional excessive sprouting occurs during tumor angiogenesis in EC-specific Nf2-deleted mice, leading to delayed tumor growth. Together, Nf2/Merlin is a crucial molecular gatekeeper for tip EC induction, capillary integrity, and proper tumor angiogenesis by suppressing VEGFR2 internalization.

10.
Front Cell Neurosci ; 16: 848764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360491

RESUMO

The neurovascular unit is a functional unit composed of neurons, glial cells, pericytes, and endothelial cells which sustain brain activity. While pericyte is a key component of the neurovascular unit, its role in cerebral blood flow regulation remains elusive. Recently, capillary stalling, which means the transient interruption of microcirculation in capillaries, has been shown to have an outsized impact on microcirculatory changes in several neurological diseases. In this study, we investigated capillary stalling and its possible causes, such as the cerebral endothelial glycocalyx and leukocyte adhesion molecules after depleting pericytes postnatally in mice. Moreover, we investigated hypoxia and gliosis as consequences of capillary stalling. Although there were no differences in the capillary structure and RBC flow, longitudinal optical coherence tomography angiography showed an increased number of stalled segments in capillaries after pericyte loss. Furthermore, the extent of the cerebral endothelial glycocalyx was decreased with increased expression of leukocyte adhesion molecules, suggesting enhanced interaction between leukocytes and endothelial cells. Finally, pericyte loss induced cerebral hypoxia and gliosis. Cumulatively, the results suggest that pericyte loss induces capillary stalling through increased interaction between leukocytes and endothelial cells in the brain.

11.
Nat Commun ; 12(1): 6287, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725372

RESUMO

Angiopoietin (Angpt)-Tie receptor 2 (Tie2) plays key roles in vascular development and homeostasis as well as pathological vascular remodeling. Therefore, Tie2-agonistic antibody and engineered Angpt1 variants have been developed as potential therapeutics for ischemic and inflammatory vascular diseases. However, their underlying mechanisms for Tie2 clustering and activation remain elusive and the poor manufacturability and stability of Angpt1 variants limit their clinical application. Here, we develop a human Tie2-agonistic antibody (hTAAB), which targets the membrane proximal fibronectin type III domain of Tie2 distinct from the Angpt-binding site. Our Tie2/hTAAB complex structures reveal that hTAAB tethers the preformed Tie2 homodimers into polygonal assemblies through specific binding to Tie2 Fn3 domain. Notably, the polygonal Tie2 clustering induced by hTAAB is critical for Tie2 activation and are resistant to antagonism by Angpt2. Our results provide insight into the molecular mechanism of Tie2 clustering and activation mediated by hTAAB, and the structure-based humanization of hTAAB creates a potential clinical application.


Assuntos
Anticorpos Monoclonais/química , Receptor TIE-2/química , Angiopoietina-2/química , Angiopoietina-2/genética , Angiopoietina-2/imunologia , Animais , Anticorpos Monoclonais/imunologia , Dimerização , Fibronectinas/química , Fibronectinas/imunologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos , Receptor TIE-2/agonistas , Receptor TIE-2/genética , Receptor TIE-2/imunologia , Remodelação Vascular
12.
J Clin Invest ; 131(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34003804

RESUMO

The upper respiratory tract is compromised in the early period of COVID-19, but SARS-CoV-2 tropism at the cellular level is not fully defined. Unlike recent single-cell RNA-Seq analyses indicating uniformly low mRNA expression of SARS-CoV-2 entry-related host molecules in all nasal epithelial cells, we show that the protein levels are relatively high and that their localizations are restricted to the apical side of multiciliated epithelial cells. In addition, we provide evidence in patients with COVID-19 that SARS-CoV-2 is massively detected and replicated within the multiciliated cells. We observed these findings during the early stage of COVID-19, when infected ciliated cells were rapidly replaced by differentiating precursor cells. Moreover, our analyses revealed that SARS-CoV-2 cellular tropism was restricted to the nasal ciliated versus oral squamous epithelium. These results imply that targeting ciliated cells of the nasal epithelium during the early stage of COVID-19 could be an ideal strategy to prevent SARS-CoV-2 propagation.


Assuntos
COVID-19/virologia , Interações entre Hospedeiro e Microrganismos , Mucosa Nasal/virologia , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/patologia , COVID-19/fisiopatologia , Diferenciação Celular , Cílios/patologia , Cílios/fisiologia , Cílios/virologia , Furina/genética , Furina/metabolismo , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Macaca , Modelos Biológicos , Mucosa Nasal/patologia , Mucosa Nasal/fisiopatologia , Pandemias , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA-Seq , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , SARS-CoV-2/fisiologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Células-Tronco/patologia , Células-Tronco/virologia , Internalização do Vírus , Replicação Viral/genética , Replicação Viral/fisiologia
13.
Cell Stem Cell ; 27(6): 905-919.e10, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33142113

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the cause of a present pandemic, infects human lung alveolar type 2 (hAT2) cells. Characterizing pathogenesis is crucial for developing vaccines and therapeutics. However, the lack of models mirroring the cellular physiology and pathology of hAT2 cells limits the study. Here, we develop a feeder-free, long-term, three-dimensional (3D) culture technique for hAT2 cells derived from primary human lung tissue and investigate infection response to SARS-CoV-2. By imaging-based analysis and single-cell transcriptome profiling, we reveal rapid viral replication and the increased expression of interferon-associated genes and proinflammatory genes in infected hAT2 cells, indicating a robust endogenous innate immune response. Further tracing of viral mutations acquired during transmission identifies full infection of individual cells effectively from a single viral entry. Our study provides deep insights into the pathogenesis of SARS-CoV-2 and the application of defined 3D hAT2 cultures as models for respiratory diseases.


Assuntos
COVID-19 , Alvéolos Pulmonares/virologia , SARS-CoV-2/fisiologia , Células-Tronco/virologia , COVID-19/virologia , Técnicas de Cultura de Células , Meios de Cultura , Humanos , Interferons/metabolismo , Modelos Biológicos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/ultraestrutura , SARS-CoV-2/ultraestrutura , Transcriptoma , Internalização do Vírus , Replicação Viral
14.
Nat Commun ; 11(1): 4102, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796823

RESUMO

Emerging evidence suggests that intestinal stromal cells (IntSCs) play essential roles in maintaining intestinal homeostasis. However, the extent of heterogeneity within the villi stromal compartment and how IntSCs regulate the structure and function of specialized intestinal lymphatic capillary called lacteal remain elusive. Here we show that selective hyperactivation or depletion of YAP/TAZ in PDGFRß+ IntSCs leads to lacteal sprouting or regression with junctional disintegration and impaired dietary fat uptake. Indeed, mechanical or osmotic stress regulates IntSC secretion of VEGF-C mediated by YAP/TAZ. Single-cell RNA sequencing delineated novel subtypes of villi fibroblasts that upregulate Vegfc upon YAP/TAZ activation. These populations of fibroblasts were distributed in proximity to lacteal, suggesting that they constitute a peri-lacteal microenvironment. Our findings demonstrate the heterogeneity of IntSCs and reveal that distinct subsets of villi fibroblasts regulate lacteal integrity through YAP/TAZ-induced VEGF-C secretion, providing new insights into the dynamic regulatory mechanisms behind lymphangiogenesis and lymphatic remodeling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fibroblastos/metabolismo , Mucosa Intestinal/metabolismo , Fatores de Transcrição/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo , Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular/genética , Células Cultivadas , Análise por Conglomerados , Ensaio de Imunoadsorção Enzimática , Fibroblastos/ultraestrutura , Citometria de Fluxo , Imunofluorescência , Hibridização in Situ Fluorescente , Mucosa Intestinal/ultraestrutura , Linfangiogênese/genética , Linfangiogênese/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fator C de Crescimento do Endotélio Vascular/genética , Proteínas de Sinalização YAP
15.
J Ginseng Res ; 44(4): 563-569, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32617036

RESUMO

BACKGROUND: White ginseng consists of the roots and rhizomes of the Panax species, and red ginseng is made by steaming and drying white ginseng. While red ginseng has both polar and nonpolar ginsenosides, previous studies showed white ginseng to have only polar ginsenosides. Because nonpolar ginsenosides are formed through the manufacture of red ginseng from white ginseng, researchers have generally thought that nonpolar ginsenosides do not exist in white ginseng. METHODS: We developed a simultaneous quantitative method for six nonpolar ginsenosides in white ginseng using reverse-phase high-performance liquid chromatography coupled with integrated pulsed amperometric detection. The nonpolar ginsenosides of white ginseng were extracted for 4 h under reflux with 50% methanol. RESULTS: Using the gradient elution system, all target components were completely separated within 50 min. Nonpolar ginsenosides were determined in the rhizome head (RH), main root (MR), lateral root, and hairy root (HR) of 6-year-old white ginseng samples obtained from several regions (Geumsan, Punggi, and Kanghwa). The total content in the HR of white ginseng was 37.8-56.8% of that in the HR of red ginseng. The total content in the MR of white ginseng was 5.9-24.3% of that in the MR of red ginseng. In addition, the total content in the RH of white ginseng was 28.5-35.8% of that in the HR of red ginseng. CONCLUSION: It was confirmed that nonpolar ginsenosides known to be specific components of red ginseng were present at substantial concentrations in the HR or RH of white ginseng.

16.
Nat Commun ; 11(1): 519, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980640

RESUMO

Fibroblastic reticular cells (FRCs) are immunologically specialized myofibroblasts of lymphoid organ, and FRC maturation is essential for structural and functional properties of lymph nodes (LNs). Here we show that YAP and TAZ (YAP/TAZ), the final effectors of Hippo signaling, regulate FRC commitment and maturation. Selective depletion of YAP/TAZ in FRCs impairs FRC growth and differentiation and compromises the structural organization of LNs, whereas hyperactivation of YAP/TAZ enhances myofibroblastic characteristics of FRCs and aggravates LN fibrosis. Mechanistically, the interaction between YAP/TAZ and p52 promotes chemokine expression that is required for commitment of FRC lineage prior to lymphotoxin-ß receptor (LTßR) engagement, whereas LTßR activation suppresses YAP/TAZ activity for FRC maturation. Our findings thus present YAP/TAZ as critical regulators of commitment and maturation of FRCs, and hold promise for better understanding of FRC-mediated pathophysiologic processes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diferenciação Celular , Fibroblastos/metabolismo , Linfonodos/citologia , Transativadores/metabolismo , Adipócitos/metabolismo , Animais , Quimiocinas/metabolismo , Fibroblastos/ultraestrutura , Linfonodos/ultraestrutura , Receptor beta de Linfotoxina/metabolismo , Mesoderma/metabolismo , Camundongos Endogâmicos C57BL , Miofibroblastos/metabolismo , Proteínas de Sinalização YAP
17.
Biomed Pharmacother ; 117: 109184, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387167

RESUMO

With the elderly population rapidly growing, the prevalence of Parkinson's disease (PD) is quickly increasing because neurodegenerative disorders are usually late-onset. Herbal medicines and formula are adjuvant therapies of conventional PD agents, which result in serious side effects with long-term use. This study evaluated the neuroprotective effects of DA-9805, a standardized herbal formula that consists of an ethanolic extract of Moutan Cortex Radix, Angelica Dahuricae Radix, and Bupleuri Radix against 6-hydroxydopamine (6-OHDA)-induced cytotoxicity in vitro and in vivo. In PC12 cells, DA-9805 at concentrations of 1 and 10 µg/mL ameliorated cell viability, which was reduced by 6-OHDA. In addition, DA-9805 activated the extracellular-regulated kinase-nuclear transcription factor-erythroid 2-related factor 2 pathway, subsequently stimulating antioxidative enzymes such as NAD(P)H:quinone oxidoreductase 1 and catalase and suppressing apoptosis. Furthermore, DA-9805 prevented 6-OHDA-induced movement impairment, as well as a decrease of dopaminergic neurons and dopamine transmission in rodents. Taken together, these results suggest that the mixed herbal formula DA-9805 may be a pharmaceutical agent for preventing or improving PD.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/tratamento farmacológico , Oxidopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Preparações de Plantas/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , NADP/metabolismo , Síndromes Neurotóxicas/metabolismo , Células PC12 , Extratos Vegetais/farmacologia , Ratos
18.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1126-1127: 121732, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376580

RESUMO

A certified reference material (CRM) for the quantification of protein, essential to manage quality control and quality assurance in protein-related works, has been developed. Amino acid analysis with conventional acid hydrolysis and isotope dilution HPLC-MS was used to establish an SI-traceable absolute protein quantification method using recombinant human growth hormone (hGH) as a model protein. The certification method was verified by comparative studies between 1) different methods of protein quantification based on microwave-assisted hydrolysis, and 2) different labs as part of the Asian Collaboration on Reference Material project with Japan, China, and Korea. Certification, evaluation of measurement uncertainty, homogeneity testing, and stability testing were carried out, after which the candidate CRM for hGH quantification was successfully certified with excellent agreement within the certified value in the two comparative studies. Although the quantification value of hGH by amino acid analysis showed good robustness in various conditions, results of intact protein analysis showed degradation profiles in temperatures higher than 4 °C. Consequently, storage and dissemination conditions should be set in accordance with stability tests. Based on the results, this method is believed to be suitable for accurate quantification of hGH. Additionally, it can also be used as a guide to preparation of CRM, and instructions for quality management of protein work for other similar proteins.


Assuntos
Hormônio do Crescimento Humano , Proteínas Recombinantes , Cromatografia Líquida de Alta Pressão/normas , Hormônio do Crescimento Humano/análise , Hormônio do Crescimento Humano/química , Humanos , Espectrometria de Massas/normas , Estabilidade Proteica , Proteínas Recombinantes/análise , Proteínas Recombinantes/química , Padrões de Referência
19.
Nature ; 572(7767): 62-66, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31341278

RESUMO

Recent work has shown that meningeal lymphatic vessels (mLVs), mainly in the dorsal part of the skull, are involved in the clearance of cerebrospinal fluid (CSF), but the precise route of CSF drainage is still unknown. Here we reveal the importance of mLVs in the basal part of the skull for this process by visualizing their distinct anatomical location and characterizing their specialized morphological features, which facilitate the uptake and drainage of CSF. Unlike dorsal mLVs, basal mLVs have lymphatic valves and capillaries located adjacent to the subarachnoid space in mice. We also show that basal mLVs are hotspots for the clearance of CSF macromolecules and that both mLV integrity and CSF drainage are impaired with ageing. Our findings should increase the understanding of how mLVs contribute to the neuropathophysiological processes that are associated with ageing.


Assuntos
Líquido Cefalorraquidiano/metabolismo , Sistema Glinfático/anatomia & histologia , Sistema Glinfático/fisiologia , Vasos Linfáticos/anatomia & histologia , Vasos Linfáticos/fisiologia , Base do Crânio/anatomia & histologia , Envelhecimento/patologia , Envelhecimento/fisiologia , Animais , Células Endoteliais/citologia , Células Endoteliais/patologia , Feminino , Fatores de Transcrição Forkhead/metabolismo , Sistema Glinfático/citologia , Sistema Glinfático/patologia , Proteínas de Homeodomínio/metabolismo , Vasos Linfáticos/citologia , Vasos Linfáticos/patologia , Linfedema/metabolismo , Linfedema/patologia , Imageamento por Ressonância Magnética , Masculino , Camundongos , Espaço Subaracnóideo/anatomia & histologia , Fatores de Tempo , Proteínas Supressoras de Tumor/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
20.
World J Stem Cells ; 11(1): 44-54, 2019 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30705714

RESUMO

BACKGROUND: Pluripotent stem cell-derived cardiomyocytes (CMs) have become one of the most attractive cellular resources for cell-based therapy to rescue damaged cardiac tissue. AIM: We investigated the regenerative potential of mouse embryonic stem cell (ESC)-derived platelet-derived growth factor receptor-α (DGFRα)+ cardiac lineage-committed cells (CLCs), which have a proliferative capacity but are in a morphologically and functionally immature state compared with differentiated CMs. METHODS: We induced mouse ESCs into PDGFRα+ CLCs and αMHC+ CMs using a combination of the small molecule cyclosporin A, the rho-associated coiled-coil kinase inhibitor Y27632, the antioxidant Trolox, and the ALK5 inhibitor EW7197. We implanted PDGFRα+ CLCs and differentiated αMHC+ CMs into a myocardial infarction (MI) murine model and performed functional analysis using transthoracic echocardiography (TTE) and histologic analysis. RESULTS: Compared with the untreated MI hearts, the anterior and septal regional wall motion and systolic functional parameters were notably and similarly improved in the MI hearts implanted with PDGFRα+ CLCs and αMHC+ CMs based on TTE. In histologic analysis, the untreated MI hearts contained a thinner ventricular wall than did the controls, while the ventricular walls of MI hearts implanted with PDGFRα+ CLCs and αMHC+ CMs were similarly thicker compared with that of the untreated MI hearts. Furthermore, implanted PDGFRα+ CLCs aligned and integrated with host CMs and were mostly differentiated into α-actinin+ CMs, and they did not convert into CD31+ endothelial cells or αSMA+ mural cells. CONCLUSION: PDGFRα+ CLCs from mouse ESCs exhibiting proliferative capacity showed a regenerative effect in infarcted myocardium. Therefore, mouse ESC-derived PDGFRα+ CLCs may represent a potential cellular resource for cardiac regeneration.

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