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1.
Circ Res ; 132(4): 432-448, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36691905

RESUMO

BACKGROUND: Matrix metalloproteinase (MMP)-12 is highly expressed in abdominal aortic aneurysms and its elastolytic function has been implicated in the pathogenesis. This concept is challenged, however, by conflicting data. Here, we sought to revisit the role of MMP-12 in abdominal aortic aneurysm. METHODS: Apoe-/- and Mmp12-/-/Apoe-/- mice were infused with Ang II (angiotensin). Expression of neutrophil extracellular traps (NETs) markers and complement component 3 (C3) levels were evaluated by immunostaining in aortas of surviving animals. Plasma complement components were analyzed by immunoassay. The effects of a complement inhibitor, IgG-FH1-5 (factor H-immunoglobulin G), and macrophage-specific MMP-12 deficiency on adverse aortic remodeling and death from rupture in Ang II-infused mice were determined. RESULTS: Unexpectedly, death from aortic rupture was significantly higher in Mmp12-/-/Apoe-/- mice. This associated with more neutrophils, citrullinated histone H3 and neutrophil elastase, markers of NETs, and C3 levels in Mmp12-/- aortas. These findings were recapitulated in additional models of abdominal aortic aneurysm. MMP-12 deficiency also led to more pronounced elastic laminae degradation and reduced collagen integrity. Higher plasma C5a in Mmp12-/- mice pointed to complement overactivation. Treatment with IgG-FH1-5 decreased aortic wall NETosis and reduced adverse aortic remodeling and death from rupture in Ang II-infused Mmp12-/- mice. Finally, macrophage-specific MMP-12 deficiency recapitulated the effects of global MMP-12 deficiency on complement deposition and NETosis, as well as adverse aortic remodeling and death from rupture in Ang II-infused mice. CONCLUSIONS: An MMP-12 deficiency/complement activation/NETosis pathway compromises aortic integrity, which predisposes to adverse vascular remodeling and abdominal aortic aneurysm rupture. Considering these new findings, the role of macrophage MMP-12 in vascular homeostasis demands re-evaluation of MMP-12 function in diverse settings.


Assuntos
Aneurisma da Aorta Abdominal , Metaloproteinase 12 da Matriz , Camundongos , Animais , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 12 da Matriz/metabolismo , Aneurisma da Aorta Abdominal/metabolismo , Apolipoproteínas E , Elastase Pancreática/metabolismo , Homeostase , Macrófagos/metabolismo , Angiotensina II/toxicidade , Angiotensina II/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout
2.
J Nucl Cardiol ; 28(2): 688-694, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31073848

RESUMO

The prevalence of cardiovascular diseases (CVD) is increased in subjects with post-traumatic stress disorder (PTSD). Vascular inflammation mediates CVD and may be assessed by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging. In this pilot study, we investigated whether subjects with PTSD have enhanced vascular and systemic inflammation compared to healthy controls, as assessed by FDG PET imaging. METHODS: A prospective group of 16 subjects (9 PTSD and 7 controls, age 34 ± 7) without prior history of CVD underwent FDG PET/CT imaging. The presence of PTSD symptoms at the time of the study was confirmed using PTSD checklist for DSM-5 (PCL5) questionnaire. Blood samples were collected to determine blood glucose, lipid and inflammatory biomarkers (tumor necrosis factor α, interleukin-1ß, and interleukin-6) levels. FDG signal in the ascending aorta, amygdala, spleen and bone marrow was quantified. RESULTS: The two groups matched closely with regards to cardiovascular risk factors. The inflammatory biomarkers were all within the normal range. There was no significant difference in FDG signal in the aorta (target to background ratio: 2.40 ± 0.29 and 2.34 ± 0.29 for control and PTSD subjects, difference: - 0.06, 95% confidence interval of difference: - 0.38 to 0.26), spleen, bone marrow, or amygdala between control and PTSD subjects. There was no significant correlation between aortic and amygdala FDG signal. However, a significant positive correlation existed between amygdala, splenic, and bone marrow FDG signal. CONCLUSION: This pilot, small study did not reveal any difference in vascular or systemic inflammation as assessed by FDG PET imaging between PTSD and healthy control subjects. Because of the small number of subjects, a modest increase in vascular inflammation, which requires larger scale studies to establish, cannot be excluded. The correlation between FDG signal in amygdala, spleen and bone marrow may reflect a link between amygdala activity and systemic inflammation.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Transtornos de Estresse Pós-Traumáticos/complicações , Vasculite/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Inflamação/diagnóstico por imagem , Masculino , Projetos Piloto , Estudos Prospectivos
3.
J Nucl Cardiol ; 27(5): 1578-1581, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32043239

RESUMO

2-deoxy-2- [18F] fluoro-D-glucose (FDG) PET is commonly used for the assessment of vessel wall inflammation. Guidelines for analysis of arterial wall FDG signal recommend the use of the average of maximal standardized uptake value (mean SUVmax) and target-to-blood (mean TBRmax) ratio. However, these methods have not been validated against a gold standard such as tissue activity ex vivo or net uptake rate of FDG (Ki) obtained using kinetic modeling. We sought to evaluate the accuracy of mean SUVmax and mean TBRmax for aortic wall FDG signal quantification in comparison with the net uptake rate of FDG. METHODS: Dynamic PET data from 13 subjects without prior history of cardiovascular disease who enrolled in a study of vascular inflammation were used for this analysis. Ex vivo measurement of plasma activity was used as the input function and voxel-by-voxel Patlak analysis was performed with t* = 20 minute to obtain the Ki image. The FDG signal in the ascending aortic wall was quantified on PET images following recent guidelines for vascular imaging to determine mean SUVmax and mean TBRmax. RESULTS: The Ki in the ascending aortic wall did not correlate with mean SUVmax (r = 0.10, P = NS), but correlated with mean TBRmax (r = 0.82, P < 0.001) (Figure 1B). Ki and Ki_max strongly correlated (R = 0.96, P < 0.0001) and similar to Ki, Ki_max did not correlate with mean SUVmax (r = 0.17, P = NS), but correlated with mean TBRmax (r = 0.83, P < 0.001). CONCLUSIONS: Kinetic modeling supports the use of mean TBRmax as a surrogate for the net uptake rate of FDG in the arterial wall. These results are relevant to any PET imaging agent, regardless of the biological significance of the tracer uptake in the vessel wall.


Assuntos
Aorta/diagnóstico por imagem , Aorta/metabolismo , Fluordesoxiglucose F18/farmacocinética , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Adulto , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
4.
Telemed J E Health ; 25(8): 693-700, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30192207

RESUMO

Background: Health problems for expatriates are common due to their vulnerability to local infectious diseases, psychosocial problems, and chronic diseases, but many problems go largely unmet in this unique population. Introduction: Telehealth counseling was developed and tested for Korean expatriates. We explored the current status of using telehealth counseling systems and showed its feasibility and acceptability in three countries. Materials and Methods: This retrospective study was based on the "Development and demonstration of telehealth counseling program for overseas Koreans" project funded by the Korea Health Industry Development Institute. In this project, we established five Digital Healthcare Centers (DHCs): 3 in Vietnam and 1 each in Uzbekistan and Cambodia. We used data from October 2016 to September 2017; descriptive analysis and one-way ANOVA were used to present detailed information. Results: A total of 442 patients made an appointment for telehealth counseling services. Overall user satisfaction rates were 96.1%. Over two thirds of patients (302/442, 68.3%) completed one-time telehealth counseling. About 13% were referred to primary care, and 17 (3.8%) were referred to specialists or tertiary hospital. The most common diagnostic category was endocrine, nutritional, and metabolic diseases (14%), followed by diseases of the circulatory system (12.3%) for one-time visit patients. Discussion: Our telehealth counseling program for expatriates was feasible and acceptable in three countries. It also has the potential to minimize language barriers and the cost of healthcare usage. Conclusion: Further research for sustainable effective telehealth systems for expatriates will be needed.


Assuntos
Emigrantes e Imigrantes , Satisfação do Paciente , Telemedicina/organização & administração , Viagem , Adolescente , Adulto , Pesos e Medidas Corporais , Criança , Pré-Escolar , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta , Estudos Retrospectivos , Fatores Socioeconômicos , Fatores de Tempo , Adulto Jovem
5.
Circulation ; 135(23): 2288-2298, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28356442

RESUMO

BACKGROUND: Bone morphogenetic protein (BMP) signaling has multiple roles in the development and function of the blood vessels. In humans, mutations in BMP receptor type 2 (BMPR2), a key component of BMP signaling, have been identified in the majority of patients with familial pulmonary arterial hypertension (PAH). However, only a small subset of individuals with BMPR2 mutation develops PAH, suggesting that additional modifiers of BMPR2 function play an important role in the onset and progression of PAH. METHODS: We used a combination of studies in zebrafish embryos and genetically engineered mice lacking endothelial expression of Vegfr3 to determine the interaction between vascular endothelial growth factor receptor 3 (VEGFR3) and BMPR2. Additional in vitro studies were performed by using human endothelial cells, including primary lung endothelial cells from subjects with PAH. RESULTS: Attenuation of Vegfr3 in zebrafish embryos abrogated Bmp2b-induced ectopic angiogenesis. Endothelial cells with disrupted VEGFR3 expression failed to respond to exogenous BMP stimulation. Mechanistically, VEGFR3 is physically associated with BMPR2 and facilitates ligand-induced endocytosis of BMPR2 to promote phosphorylation of SMADs and transcription of ID genes. Conditional, endothelial-specific deletion of Vegfr3 in mice resulted in impaired BMP signaling responses, and significantly worsened hypoxia-induced pulmonary hypertension. Consistent with these data, we found significant decrease in VEGFR3 expression in pulmonary arterial endothelial cells from human PAH subjects, and reconstitution of VEGFR3 expression in PAH pulmonary arterial endothelial cells restored BMP signaling responses. CONCLUSIONS: Our findings identify VEGFR3 as a key regulator of endothelial BMPR2 signaling and a potential determinant of PAH penetrance in humans.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/biossíntese , Endotélio Vascular/metabolismo , Hipertensão Pulmonar/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Células Cultivadas , Endotélio Vascular/patologia , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Peixe-Zebra
6.
Global Health ; 14(1): 120, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497503

RESUMO

BACKGROUND: With the significant growth of migration and expatriation, facilitated by increased global mobility, the number of Koreans living abroad as of 2016 is approximately 7.4 million (15% of the Korean population). Healthcare utilization or health problems, especially among expatriates in developing countries, have not been well researched despite the various health risks these individuals are exposed to. Consequently, we identified the health utilization patterns and healthcare needs among Korean expatriates in Vietnam, Cambodia, and Uzbekistan. METHODS: This cross-sectional survey examined 429 Korean expatriates living in Vietnam (n = 208), Cambodia (n = 60), and Uzbekistan (n = 161) who had access to the Internet and were living abroad for at least 6 months. A 67-item questionnaire was used, and feedback was received via an online survey program. Stepwise logistic regression analyses were performed to evaluate factors associated with unmet healthcare needs and preferences of certain type of telemedicine. RESULTS: We found that 45.5% (195/429) of respondents had used medical services in their country of stay. Among those who visited health institutions > 3 times, the most popular choice was general hospitals (39.4%, 15/38); however, they initially visited Korean doctors' or local doctors' offices. The most essential criteria for healthcare service facilities was a "skilled professional" (39.3%, 169/429), 42% wanted a health program for chronic disease management, and 30% wanted specialized internal medicine. A substantial number wanted to access telemedicine services and were willing to pay for this service. They were particularly interested in experts' second opinion (61.5%, 264/429) and quick, 24-h medical consultations (60.8%, 261/429). Having unmet healthcare needs and being younger was strongly associated with all types of telemedicine networks. CONCLUSIONS: Nearly half of the expatriates in developing countries had unmet healthcare needs. Telemedicine is one potential solution to meet these needs, especially in developing countries.


Assuntos
Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Telemedicina , Adulto , Idoso , Camboja , Estudos Transversais , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Uzbequistão , Vietnã , Adulto Jovem
7.
Circulation ; 133(4): 409-21, 2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-26659946

RESUMO

BACKGROUND: Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here, we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. METHODS AND RESULTS: Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2- and VEGF-induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, and pathological ocular neovascularization and wound healing, as well. CONCLUSIONS: These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2, and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Polaridade Celular/fisiologia , Células Endoteliais/fisiologia , Deleção de Genes , Neovascularização Fisiológica/fisiologia , Proteínas Oncogênicas/genética , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Sequência de Aminoácidos , Animais , Marcação de Genes/métodos , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Proteínas Oncogênicas/deficiência
8.
Proc Natl Acad Sci U S A ; 110(11): 4410-5, 2013 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-23401498

RESUMO

Olfactory receptors are G protein-coupled receptors that mediate olfactory chemosensation and serve as chemosensors in other tissues. We find that Olfr78, an olfactory receptor expressed in the kidney, responds to short chain fatty acids (SCFAs). Olfr78 is expressed in the renal juxtaglomerular apparatus, where it mediates renin secretion in response to SCFAs. In addition, both Olfr78 and G protein-coupled receptor 41 (Gpr41), another SCFA receptor, are expressed in smooth muscle cells of small resistance vessels. Propionate, a SCFA shown to induce vasodilation ex vivo, produces an acute hypotensive response in wild-type mice. This effect is differentially modulated by disruption of Olfr78 and Gpr41 expression. SCFAs are end products of fermentation by the gut microbiota and are absorbed into the circulation. Antibiotic treatment reduces the biomass of the gut microbiota and elevates blood pressure in Olfr78 knockout mice. We conclude that SCFAs produced by the gut microbiota modulate blood pressure via Olfr78 and Gpr41.


Assuntos
Pressão Sanguínea/fisiologia , Intestinos/microbiologia , Rim/metabolismo , Metagenoma/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores Odorantes/metabolismo , Renina/metabolismo , Transdução de Sinais/fisiologia , Animais , Biomassa , Pressão Sanguínea/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/microbiologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Knockout , Propionatos/metabolismo , Propionatos/farmacologia , Receptores Acoplados a Proteínas G/genética , Receptores Odorantes/genética , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
9.
Development ; 138(22): 5027-37, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22028034

RESUMO

Adipose tissue is a structure highly specialized in energy storage. The adipocyte is the parenchymal component of adipose tissue and is known to be mesoderm or neuroectoderm in origin; however, adipocyte development remains poorly understood. Here, we investigated the development of adipose tissue by analyzing postnatal epididymal adipose tissue (EAT) in mouse. EAT was found to be generated from non-adipose structure during the first 14 postnatal days. From postnatal day 1 (P1) to P4, EAT is composed of multipotent progenitor cells that lack adipogenic differentiation capacity in vitro, and can be regarded as being in the 'undetermined' state. However, the progenitor cells isolated from P4 EAT obtain their adipogenic differentiation capacity by physical interaction generated by cell-to-matrix and cell-to-cell contact both in vitro and in vivo. In addition, we show that impaired angiogenesis caused by either VEGFA blockade or macrophage depletion in postnatal mice interferes with adipose tissue development. We conclude that appropriate interaction between the cellular and matrix components along with proper angiogenesis are mandatory for the development of adipose tissue.


Assuntos
Tecido Adiposo/crescimento & desenvolvimento , Distribuição da Gordura Corporal , Células 3T3-L1 , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Animais Recém-Nascidos , Diferenciação Celular/genética , Células Cultivadas , Epididimo , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Tempo
10.
Cell Mol Life Sci ; 70(10): 1779-92, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23479133

RESUMO

Notch cell interaction mechanism governs cell fate decisions in many different cell contexts throughout the lifetime of all Metazoan species. It links the fate of one cell to that of its neighbors through cell-to-cell contacts, and binding of Notch receptors expressed on one cell to their membrane bound ligands on an adjacent cell. Environmental cues, such as growth factors and extracellular matrix molecules, superimpose a dynamic regulation on this canonical Notch signaling pathway. In this review, we will focus on Notch signaling in the vertebrate vascular and nervous systems and examine its role in angiogenesis, neurogenesis, and neurovascular interactions. We will also highlight the molecular relationships of the Notch pathway with vascular endothelial growth factors (VEGFs) and their high-affinity tyrosine kinase VEGF receptors, key regulators of both angiogenesis and neurogenesis.


Assuntos
Células Endoteliais/metabolismo , Neurônios/metabolismo , Receptores Notch/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Células Endoteliais/citologia , Humanos , Neovascularização Patológica/metabolismo , Neurogênese , Neurônios/citologia , Transdução de Sinais , Fatores de Crescimento do Endotélio Vascular/metabolismo
11.
Blood ; 115(5): 957-64, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19897586

RESUMO

The stromal vascular fraction (SVF) in adipose tissue contains a pool of various stem and progenitor cells, but the existence of hematopoietic stem and progenitor cells (HSPCs) in the SVF has not been seriously considered. We detected the presence of HSPCs in the SVF by phenotypically probing with Lin(-)Sca-1(+)c-kit(+) (LSK) and functionally confirming the presence using colony-forming cell assay and assessing the long-term multilineage reconstitution ability after SVF transplantation. The LSK population in the SVF was 0.004% plus or minus 0.001%, and 5 x 10(5) freshly isolated SVF cells gave rise to 13 plus or minus 4 multilineage colonies. In addition, 0.15% plus or minus 0.03% of SVF cells was home to bone marrow (BM), especially near vascular and endosteal regions, 24 hours after blood transplantation. SVF transplantation was capable of generating a long-term (> 16 weeks), but variable extent (2.1%-32.1%) multilineage reconstitution in primary recipients, which was subsequently transferred to the secondary recipients by BM transplantation. All HSPCs within the SVF originated from the BM. Furthermore, the granulocyte-colony-stimulating factor (G-CSF) mobilization of HSPCs from BM markedly elevated the number of phenotypic and functional HSPCs in the SVF, which induced a high efficiency long-term reconstitution in multilineage hematopoiesis in vivo. Our results provide compelling evidence that adipose tissue is a novel extramedullary tissue possessing phenotypic and functional HSPCs.


Assuntos
Tecido Adiposo/citologia , Linhagem da Célula , Células-Tronco Hematopoéticas/citologia , Tecido Adiposo/metabolismo , Animais , Antígenos Ly/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Ensaio de Unidades Formadoras de Colônias , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Hematopoese , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Imunofenotipagem , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-kit/metabolismo
12.
J Biomech ; 141: 111179, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35759974

RESUMO

Mechanical homeostasis emerges following normal development of the arterial wall and requires thereafter a slow balanced degradation and deposition of extracellular matrix constituents within an unchanging mechanical state. Recent findings suggest that homeostasis is compromised in arterial aging, which contributes to the structural stiffening that is characteristic of aged central arteries. Matrix metalloproteinases (MMPs) have strong proteolytic activity and play fundamental roles in matrix turnover. Here, we use Mmp12-/- mice to examine effects of a potent metalloelastase, MMP-12, on the biomechanical phenotype of the thoracic and abdominal aorta in young and naturally aged mice. A key finding is that germline deletion of the gene (Mmp12) that encodes MMP-12 alters biomechanical properties from normal more in young adult than in older adult mice. Consequently, percent changes in biomechanical properties during aortic aging are greater in wild-type than in MMP-12 deficient mice, though with similar overall decreases in elastic energy storage and distensibility and increases in calculated pulse wave velocity. Reduced elastic energy storage compromises the ability of the aorta to augment antegrade and retrograde blood flow while an increased pulse wave velocity can adversely affect end organs, both conditions being characteristic of aortic aging in humans. In summary, MMP-12 is fundamental for establishing homeostatic values of biomechanical metrics in the aorta and its absence leads to a pre-aged aortic phenotype in young mice.


Assuntos
Metaloproteinase 12 da Matriz , Análise de Onda de Pulso , Idoso , Animais , Aorta Abdominal , Homeostase , Humanos , Metaloproteinase 12 da Matriz/genética , Metaloproteinases da Matriz , Camundongos , Fenótipo , Adulto Jovem
13.
J Cell Biol ; 221(7)2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35695893

RESUMO

Atherosclerosis, the major cause of myocardial infarction and stroke, results from converging inflammatory, metabolic, and biomechanical factors. Arterial lesions form at sites of low and disturbed blood flow but are suppressed by high laminar shear stress (LSS) mainly via transcriptional induction of the anti-inflammatory transcription factor, Kruppel-like factor 2 (Klf2). We therefore performed a whole genome CRISPR-Cas9 screen to identify genes required for LSS induction of Klf2. Subsequent mechanistic investigation revealed that LSS induces Klf2 via activation of both a MEKK2/3-MEK5-ERK5 kinase module and mitochondrial metabolism. Mitochondrial calcium and ROS signaling regulate assembly of a mitophagy- and p62-dependent scaffolding complex that amplifies MEKK-MEK5-ERK5 signaling. Blocking the mitochondrial pathway in vivo reduces expression of KLF2-dependent genes such as eNOS and inhibits vascular remodeling. Failure to activate the mitochondrial pathway limits Klf2 expression in regions of disturbed flow. This work thus defines a connection between metabolism and vascular inflammation that provides a new framework for understanding and developing treatments for vascular disease.


Assuntos
Células Endoteliais , Fatores de Transcrição Kruppel-Like , Mitocôndrias , Estresse Mecânico , Aterosclerose/patologia , Sistemas CRISPR-Cas , Sinalização do Cálcio , Células Endoteliais/metabolismo , Humanos , Inflamação , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , MAP Quinase Quinase 5 , MAP Quinase Quinase Quinase 2 , MAP Quinase Quinase Quinase 3 , Mitocôndrias/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/genética , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Espécies Reativas de Oxigênio
14.
J Extracell Biol ; 1(12): e70, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38938599

RESUMO

Extracellular vesicles (EVs) released by a variety of cell types have been shown to act as a natural delivery system for bioactive molecules such as RNAs and proteins. EV therapy holds great promise as a safe and cell-free therapy for many immunological and degenerative diseases. However, translation to clinical application is limited by several factors, including insufficient large-scale manufacturing technologies and low yield. We have developed a novel drug delivery platform technology, BioDrone™, based on cell-derived vesicles (CDVs) produced from diverse cell sources by using a proprietary extrusion process. This extrusion technology generates nanosized vesicles in far greater numbers than naturally obtained EVs. We demonstrate that the CDVs are surrounded by a lipid bilayer membrane with a correct membrane topology. Physical, biochemical and functional characterisation results demonstrate the potential of CDVs to act as effective therapeutics. Umbilical cord mesenchymal stem cell (UCMSC)-derived CDVs exhibit a biological activity that is similar to UCMSCs or UCMSC-derived EVs. Lastly, we present the establishment of a GMP-compliant process to allow the production of a large number of UCMSC-CDVs in a reproducible manner. GMP-compliant manufacturing of CDVs will facilitate the preclinical and clinical evaluation of these emerging therapeutics in anti-inflammatory or regenerative medicine. This study also represents a crucial step in the development of this novel drug delivery platform based on CDVs.

15.
Children (Basel) ; 8(5)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067734

RESUMO

BACKGROUND: Children experience seasonal variations in growth whereby height increases most in spring and least in autumn, and weight increases least in spring and most in autumn. We hypothesized that activity restriction caused by efforts to contain the spread of coronavirus disease 2019 (COVID-19) would result in increased body mass index (BMI) in children, differing from conventional seasonal growth variations. METHODS: We included 169 children who visited endocrine clinics of three hospitals in Korea at regular intervals under the same conditions for two years. Visit dates were D1 (January, 2019), D2 (July, 2019), D3 (January, 2020) before the COVID-19 outbreak, and D4 (July, 2020) during the pandemic. Differences in the z-score for height (HT), weight (WT), and BMI among time points and between spring seasons (i.e., S1-S3) were compared. RESULTS: There were significant differences in BMIz among time points, which decreased from D1-D2 and increased from D2-D3 and D3-D4. WTz significantly increased from D2-D3 and D3-D4. BMIz values of S1 (spring 2019) and S3 (spring 2020) were -0.05 and 0.16, respectively, showing significant differences. WTz values between S1 and S3 were significantly different (-0.02 vs. 0.13). CONCLUSIONS: In 2019, there were conventional seasonal variations in BMIz, which declined in spring and increased in autumn, while in 2020, BMIz increased even in spring. The COVID-19 pandemic may have affected seasonal variations in the growth of children attending endocrine clinics.

16.
Theranostics ; 11(12): 5876-5888, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897887

RESUMO

Inflammation plays a major role in the pathogenesis of several vascular pathologies, including abdominal aortic aneurysm (AAA). Evaluating the role of inflammation in AAA pathobiology and potentially outcome in vivo requires non-invasive tools for high-resolution imaging. We investigated the feasibility of X-ray computed tomography (CT) imaging of phagocytic activity using nanoparticle contrast agents to predict AAA outcome. Methods: Uptake of several nanoparticle CT contrast agents was evaluated in a macrophage cell line. The most promising agent, Exitron nano 12000, was further characterized in vitro and used for subsequent in vivo testing. AAA was induced in Apoe-/- mice through angiotensin II (Ang II) infusion for up to 4 weeks. Nanoparticle biodistribution and uptake in AAA were evaluated by CT imaging in Ang II-infused Apoe-/- mice. After imaging, the aortic tissue was harvested and used from morphometry, transmission electron microscopy and gene expression analysis. A group of Ang II-infused Apoe-/- mice underwent nanoparticle-enhanced CT imaging within the first week of Ang II infusion, and their survival and aortic external diameter were evaluated at 4 weeks to address the value of vessel wall CT enhancement in predicting AAA outcome. Results: Exitron nano 12000 showed specific uptake in macrophages in vitro. Nanoparticle accumulation was observed by CT imaging in tissues rich in mononuclear phagocytes. Aortic wall enhancement was detectable on delayed CT images following nanoparticle administration and correlated with vessel wall CD68 expression. Transmission electron microscopy ascertained the presence of nanoparticles in AAA adventitial macrophages. Nanoparticle-induced CT enhancement on images obtained within one week of AAA induction was predictive of AAA outcome at 4 weeks. Conclusions: By establishing the feasibility of CT-based molecular imaging of phagocytic activity in AAA, this study links the inflammatory signal on early time point images to AAA evolution. This readily available technology overcomes an important barrier to cross-sectional, longitudinal and outcome studies, not only in AAA, but also in other cardiovascular pathologies and facilitates the evaluation of modulatory interventions, and ultimately upon clinical translation, patient management.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Macrófagos/patologia , Fagócitos/patologia , Angiotensina II/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Aneurisma da Aorta Abdominal/metabolismo , Apolipoproteínas E/metabolismo , Modelos Animais de Doenças , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fagócitos/metabolismo , Tomografia Computadorizada por Raios X/métodos
17.
Am J Pathol ; 175(4): 1733-45, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762711

RESUMO

Lymphatic vessels in the diaphragm are essential for draining peritoneal fluid, but little is known about their pathological changes during inflammation. Here we characterized diaphragmatic lymphatic vessels in a peritonitis model generated by daily i.p. administration of lipopolysaccharide (LPS) in mice. Intraperitoneal LPS increased lymphatic density, branching, sprouts, connections, and network formation in the diaphragm in time- and dose-dependent manners. These changes were reversible on discontinuation of LPS administration. The LPS-induced lymphatic density and remodeling occur mainly through proliferation of lymphatic endothelial cells. CD11b+ macrophages were massively accumulated and closely associated with the lymphatic vessels changed by i.p. LPS. Both RT-PCR assays and experiments with vascular endothelial growth factor-C/D blockade and macrophage-depletion indicated that the CD11b+ macrophage-derived lymphangiogenic factors vascular endothelial growth factor-C/D could be major mediators of LPS-induced lymphangiogenesis and lymphatic remodeling through paracrine activity. Functional assays with India ink and fluorescein isothiocyanate-microspheres indicated that impaired peritoneal fluid drainage in diaphragm of LPS-induced peritonitis mice was due to inflammatory fibrosis and massive attachment of CD11b+ macrophages on the peritoneal side of the diaphragmatic lymphatic vessels. These findings reveal that CD11b+ macrophages play an important role in i.p. LPS-induced aberrant lymphangiogenesis and lymphatic dysfunction in the diaphragm.


Assuntos
Antígeno CD11b/metabolismo , Diafragma/fisiopatologia , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Linfangiogênese/efeitos dos fármacos , Vasos Linfáticos/fisiopatologia , Macrófagos/imunologia , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/patologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Clodrônico/farmacologia , Diafragma/efeitos dos fármacos , Diafragma/patologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Injeções Intraperitoneais , Ligantes , Lipossomos , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Vasos Linfáticos/efeitos dos fármacos , Vasos Linfáticos/patologia , Macrófagos/efeitos dos fármacos , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Peritonite/induzido quimicamente , Peritonite/fisiopatologia , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo
18.
Circ Res ; 100(4): e47-57, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17272806

RESUMO

Here we report the discovery of a characteristic dense vascular network (DVN) in the tip portion of epididymal adipose tissue in adult mice. The DVN is formed by angiogenesis rather than by vasculogenesis, and has functional blood circulation. This DVN and its subsequent branching may provide a new functional route for adipogenesis. The recruitment, infiltration, and accumulation of bone marrow-derived LYVE-1(+) macrophages in the tip region are crucial for the formation of the DVN. Matrix metalloproteinases (MMPs) and the VEGF-VEGFR2 system are responsible not only for the formation of the DVN, but also for the recruitment and infiltration of LYVE-1(+) macrophages into the epididymal adipose tissue tip region. SDF-1, but not the MCP-1-CCR2 system, is a critical factor in recruitment and ongoing retention of macrophages in this area. We also demonstrate that the tip region of epididymal adipose tissue is highly hypoxic, and thus provides a microenvironment conducive to the high expression and enhanced activities of VEGF, VEGFR2, MMPs, and SDF-1 in autocrine and paracrine manners, to create an ideal niche for the recruitment, retention, and angiogenic action of macrophages. These findings shed light on the complex interplay between macrophage infiltration, angiogenesis, and adipogenesis in the tip region of adult epididymal adipose tissue, and provide novel insight into the regulation of alternative outgrowth of adipose tissue.


Assuntos
Tecido Adiposo/fisiologia , Glicoproteínas/fisiologia , Macrófagos/fisiologia , Neovascularização Fisiológica/fisiologia , Adipogenia/fisiologia , Tecido Adiposo/irrigação sanguínea , Tecido Adiposo/crescimento & desenvolvimento , Animais , Movimento Celular/fisiologia , Epididimo/irrigação sanguínea , Epididimo/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Glicoproteínas/biossíntese , Glicoproteínas/genética , Macrófagos/citologia , Masculino , Proteínas de Membrana Transportadoras , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
19.
J Telemed Telecare ; 25(4): 241-248, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29933721

RESUMO

INTRODUCTION: Rapid globalization has produced a growing demand for the chronic care management of overseas populations living in medically underserved areas. This study investigated the utilization pattern of telehealth counselling among overseas Koreans with high blood pressure, and evaluated the relationships between mobile self-monitoring application and blood pressure reduction. METHODS: A global chronic management programme consisting of lifestyle modification and self-monitoring blood pressure was launched to provide a telehealth counselling service for Koreans with high blood pressure living in Vietnam from August 2016 to December 2017. During the first telehealth session, doctors educated patients on lifestyle modifications using a mobile self-monitoring application and checked the change of blood pressure in a follow-up telehealth visit. We examined utilization patterns and compared the blood pressure change among the mobile self-monitoring group versus the control group using Wilcoxon signed rank tests. RESULTS: A total of 234 patients with systolic blood pressure of more than 130 mmHg or diastolic blood pressure of more than 80 mmHg were registered, installed the mobile app and were provided with automated blood pressure devices with the telehealth counselling service by Korean doctors. A follow-up telehealth counselling session was provided at three months. Only 15% (36/234) received two or more telehealth counselling sessions. Significant differences were found in the mean change of systolic blood pressure at three months in the monitoring group and the non-monitoring group (-16.0 vs. -5.7, p = 0.008). DISCUSSION: In this unique telehealth study, a mobile self-monitoring application was associated with significantly reducing systolic blood pressure levels in three months. Encouraging patients via a mobile application that includes a self-monitoring function might have the potential for self-managing chronic diseases, especially in resource-limited environments.


Assuntos
Determinação da Pressão Arterial/estatística & dados numéricos , Monitorização Ambulatorial da Pressão Arterial/estatística & dados numéricos , Aconselhamento/estatística & dados numéricos , Hipertensão/diagnóstico , Telemedicina/estatística & dados numéricos , Idoso , Pressão Sanguínea , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Hipertensão/fisiopatologia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis/estatística & dados numéricos , Monitorização Fisiológica , Vietnã
20.
Sci Rep ; 8(1): 11647, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30076321

RESUMO

Matrix metalloproteinases (MMPs) are involved in tissue remodeling. Accordingly, MMP inhibitors and related radiolabeled analogs are important tools for MMP-targeted imaging and therapy in a number of diseases. Herein, we report design, synthesis, and evaluation of a new Arginine-containing macrocyclic hydroxamate analog, RYM, its hydrazinonicotinamide conjugate, RYM1 and 99mTc-labeled analog 99mTc-RYM1 for molecular imaging. RYM exhibited potent inhibition against a panel of recombinant human (rh) MMPs in vitro. RYM1 was efficiently labeled with 99mTcO4- to give 99mTc-RYM1 in a high radiochemical yield and high radiochemical purity. RYM1 and its decayed labeling product displayed similar inhibition potencies against rhMMP-12. Furthermore, 99mTc-RYM1 exhibited specific binding with lung tissue from lung-specific interleukin-13 transgenic mice, in which MMP activity is increased in conjunction with tissue remodeling and inflammation. The results support further development of such new water-soluble Arginine-containing macrocyclic hydroxamate MMP inhibitors for targeted imaging and therapy.


Assuntos
Ácidos Hidroxâmicos/farmacologia , Pneumopatias/tratamento farmacológico , Compostos Macrocíclicos/química , Inibidores de Metaloproteinases de Matriz/química , Animais , Arginina/química , Arginina/metabolismo , Modelos Animais de Doenças , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Cinética , Pneumopatias/patologia , Compostos Macrocíclicos/administração & dosagem , Compostos Macrocíclicos/síntese química , Inibidores de Metaloproteinases de Matriz/administração & dosagem , Inibidores de Metaloproteinases de Matriz/síntese química , Metaloproteinases da Matriz/química , Metaloproteinases da Matriz/genética , Camundongos , Camundongos Transgênicos , Imagem Molecular , Estrutura Molecular , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/química , Tecnécio/química
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