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1.
Dermatol Surg ; 49(11): 989-994, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37606659

RESUMO

BACKGROUND: Patient anxiety can complicate surgical outcomes by elevating blood pressure, increasing the need for postoperative pain management, and reducing overall patient satisfaction. Despite the use of anxiolytic medications in outpatient procedures, there is limited comparative evidence on the efficacy and safety of these agents in Mohs micrographic surgery. OBJECTIVE: To compare the effectiveness and safety of different preprocedural anxiolytic agents in Mohs surgery on perioperative patient anxiety and patient satisfaction. MATERIALS AND METHODS: A double-blinded, randomized, placebo-controlled trial was conducted of 6 different preprocedural anxiolytic agents (lorazepam, diazepam, alprazolam, gabapentin, pregabalin, and melatonin) in 350 patients undergoing Mohs surgery. Anxiety and vital signs were recorded. RESULTS: Diazepam demonstrated a statistically significant, sustained reduction in anxiety levels compared with placebo ( p = .03). Gabapentin significantly reduced early anxiety ( p = .02). Alprazolam showed a trend to early anxiety reduction ( p = .08). Lorazepam ( p = .73), pregabalin ( p = .53), and melatonin ( p = .24) failed to reduce patient anxiety compared with placebo at any time point. No anxiolytic significantly impacted any patient vital sign or cognition. CONCLUSION: Although short-acting benzodiazepines and gamma-aminobutyric acid medications may have transient anxiolytic effects, a single oral dose of 5 mg of diazepam can provide a sustained anxiolytic effect in Mohs surgery, with excellent patient safety.


Assuntos
Ansiolíticos , Cirurgia de Mohs , Humanos , Alprazolam/efeitos adversos , Ansiolíticos/efeitos adversos , Ansiedade/etiologia , Ansiedade/prevenção & controle , Ansiedade/tratamento farmacológico , Diazepam/efeitos adversos , Método Duplo-Cego , Gabapentina , Lorazepam , Melatonina , Pregabalina
2.
J Cosmet Dermatol ; 20(11): 3378-3381, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34536068

RESUMO

COVID-19 continues to affect the delivery of healthcare services, as practices across North America gradually re-open with new safety measures and practice guidelines. Specifically in dermatology, clinical care is delivered in close physician-patient proximity through physical examination and the use of additional diagnostic and therapeutic procedures. We designed a 10-question survey to better understand how COVID-19 has impacted the delivery of care in North American dermatology practices. Survey questions explored themes including changes in patient volumes, the use of virtual visits/teledermatology, the frequency of aesthetic and surgical procedures, and other related topics. We invited 102 board-certified dermatologists working in a variety of medical, aesthetic, surgical, and mixed practices, to participate in our survey hosted through Qualtrics XM. These dermatologists were selected based on their geographic location and our ability to access their contact information. Each dermatologist received an individualized e-mail and survey link; however, all survey responses were anonymized. In 2.5 weeks after survey invitations were sent, the survey was viewed and completed by 71 and 54 dermatologists, respectively. The second wave of e-mails was sent to the remaining 48 dermatologists who had not yet completed the survey, after which 15 participants both viewed and completed the survey. In total, 69 responses were recorded with an overall response rate of 67.6%. We report decreased patient volume capacity, fewer aesthetic and surgical procedures, and an increase in the use of virtual medicine among board-certified North American dermatologists. However, this represents a reflection on perspectives at a single time point in a rapidly evolving situation. Understanding the full scope of the impact that COVID-19 continues to have on dermatologic care is paramount to effectively serve our patients.


Assuntos
COVID-19 , Dermatologia , Humanos , América do Norte , SARS-CoV-2 , Inquéritos e Questionários
3.
J Natl Cancer Inst ; 111(11): 1228-1231, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30923800

RESUMO

There is limited information on how indoor tanning promotes melanoma development. We investigated indoor tanning use in patients with melanomas in sun-exposed skin and studied the clinicopathological and molecular characteristics in relation to indoor tanning exposure. Patients from a multidisciplinary clinic for cutaneous cancers completed standardized questionnaires on risk factors for melanoma as a component of medical history at their initial consultations. For this study, we included patients from December 2013 to May 2015. The 114 patients who reported indoor tanning exposure were younger at diagnosis than the 222 patients who did not (51.5 vs 64.0 years, two-sided P < .001). BRAF V600E genotype was more prevalent in ever-users than in nonusers (42.9% vs 28.3%, two-sided P = .04) and higher in ever-users who initiated indoor tanning prior to age 25 years compared with age 25 years or older (62.2% vs 31.1%, two-sided P = .003). There were more melanomas in intermittently sun-exposed skin in ever-users than nonusers (65.7% vs 51.9%, respectively, two-sided P = .02). Our data suggest indoor tanning may promote melanomas that arise in skin with low-chronic sun-induced damage through BRAF V600E-mediated melanomagenesis.


Assuntos
Melanoma/etiologia , Mutação , Neoplasias Induzidas por Radiação/etiologia , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/etiologia , Banho de Sol/estatística & dados numéricos , Raios Ultravioleta/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Melanoma/metabolismo , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/metabolismo , Neoplasias Induzidas por Radiação/patologia , Prognóstico , Fatores de Risco , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Inquéritos e Questionários , Adulto Jovem
4.
J Cutan Med Surg ; 22(4): 384-389, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29411629

RESUMO

We believe cellphone text messages are commonly used in medical practice whether in rural or urban settings and that clinical photos are often attached to them. Our interest is the use of this technology to provide dermatology service to rural and remote British Columbia. Concern has been expressed about the security of confidential information and adequacy of privacy protection in such an application. We have found little published information about the extent of texting in rural and remote settings (and none in our jurisdiction) or the number and nature of privacy breaches that have actually occurred as a result. To obtain such information, we first set out to survey medical practitioners about their actual use. The results reported here are from medical trainees enrolled with the University of British Columbia who are in both rural and urban settings.


Assuntos
Telefone Celular/estatística & dados numéricos , Comunicação , Atenção à Saúde/métodos , Estudantes de Medicina/estatística & dados numéricos , Envio de Mensagens de Texto/estatística & dados numéricos , Adulto , Colúmbia Britânica , Estudos Transversais , Humanos , População Rural , População Urbana , Adulto Jovem
7.
J Cutan Med Surg ; 18(6): 436-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25348767

RESUMO

BACKGROUND: Sweet syndrome (SS) is a rare skin condition that is classically idiopathic in etiology, but can also be triggered by malignancy, drug reaction, or infection. Both chronic hepatitis C infection and antiviral agents for the treatment of hepatitis C have been postulated to be possible triggers of SS. OBJECTIVE: Herein, we present a case of SS in a patient with untreated chronic hepatitis C and cirrhosis but no other significant comorbidities.


Assuntos
Hepatite C Crônica/complicações , Cirrose Hepática/complicações , Síndrome de Sweet/complicações , Dermatoses Faciais/complicações , Feminino , Dermatoses da Mão/complicações , Humanos , Cirrose Hepática/virologia , Pessoa de Meia-Idade , Dermatoses do Couro Cabeludo/complicações
8.
J Cutan Med Surg ; 17(6): 387-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24138974

RESUMO

BACKGROUND: As a product of electronic health, teledermatology is a cost-effective means of improving access to care, facilitating specialist consultations, and supporting patient self-management. Even so, use of traditional teledermatology services is limited by infrastructure and costs in the form of digital cameras, computers, and Internet access. METHODS: Considering the significant improvement in smartphone camera resolution and the rapidly increasing number of physicians using smartphones, we explored the use of smartphones as reliable, effective clinical tools in store-and-forward teledermatology. We describe the technical specifications of modern smartphone cameras, the widespread use of smartphones by physicians, and the advantages of smartphones over traditional camera and Internet teledermatology, and we propose recommendations as to how mobile teledermatology may be more effectively used in modern dermatologic practice.


Assuntos
Telefone Celular , Dermatologia/métodos , Telemedicina/tendências , Análise Custo-Benefício , Humanos , Telemedicina/economia
9.
J Mol Cell Cardiol ; 50(4): 606-12, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21276799

RESUMO

The heart is a mechanosensitive organ that adapts its morphology to changing hemodynamic conditions via a process named mechanotransduction, which is the primary means of detecting mechanical stress in the extracellular environment. In the heart, mechanical signals are propagated into the intracellular space primarily via cell adhesion complexes and are subsequently transmitted from cell to cell via paracrine signaling. Enhanced excitation-contraction coupling increases myocardial contractility in various experimental models. However, these animal models routinely show increased susceptibility to biomechanical stress with the development of early ventricular dilation and reduced systolic function in the setting of adverse myocardial remodeling. The enhanced susceptibility of the PI3Kγ knockout mice to biomechanical stress is linked to a cAMP-dependent up-regulation of matrix metalloproteinase with a loss of N-cadherin mediated cell adhesion. Enhancing cell-cell adhesion and cell-ECM interaction will promote the salutary effects of enhanced intracellular Ca(2+) cycling on whole heart function and booster the therapeutic potential of normalizing intracellular Ca(2+) cycling in patients with heart failure.


Assuntos
Classe Ib de Fosfatidilinositol 3-Quinase/genética , Acoplamento Excitação-Contração/fisiologia , Cardiopatias/genética , Cardiopatias/fisiopatologia , Animais , Acoplamento Excitação-Contração/genética , Humanos , Camundongos , Camundongos Knockout , Modelos Biológicos
10.
Cardiovasc Res ; 91(1): 151-61, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21285291

RESUMO

AIMS: Angiotensin-converting enzyme 2 (ACE2) is an important negative regulator of the renin-angiotensin system. Loss of ACE2 enhances the susceptibility to heart disease but the mechanism remains elusive. We hypothesized that ACE2 deficiency activates the NADPH oxidase system in pressure overload-induced heart failure. METHODS AND RESULTS: Using the aortic constriction model, we subjected wild-type (Ace2(+/y)), ACE2 knockout (ACE2KO, Ace2(-/y)), p47(phox) knockout (p47(phox)KO, p47(phox-)(/-)), and ACE2/p47(phox) double KO mice to pressure overload. We examined changes in peptide levels, NADPH oxidase activity, gene expression, matrix metalloproteinases (MMP) activity, pathological signalling, and heart function. Loss of ACE2 resulted in enhanced susceptibility to biomechanical stress leading to eccentric remodelling, increased pathological hypertrophy, and worsening of systolic performance. Myocardial angiotensin II (Ang II) levels were increased, whereas Ang 1-7 levels were lowered. Activation of Ang II-stimulated signalling pathways in the ACE2-deficient myocardium was associated with increased expression and phosphorylation of p47(phox), NADPH oxidase activity, and superoxide generation, leading to enhanced MMP-mediated degradation of the extracellular matrix. Additional loss of p47(phox) in the ACE2KO mice normalized the increased NADPH oxidase activity, superoxide production, and systolic dysfunction following pressure overload. Ang 1-7 supplementation suppressed the increased NADPH oxidase and rescued the early dilated cardiomyopathy in pressure-overloaded ACE2KO mice. CONCLUSION: In the absence of ACE2, biomechanical stress triggers activation of the myocardial NAPDH oxidase system with a critical role of the p47(phox) subunit. Increased production of superoxide, activation of MMP, and pathological signalling leads to severe adverse myocardial remodelling and dysfunction in ACE2KO mice.


Assuntos
Cardiomiopatia Dilatada/prevenção & controle , Insuficiência Cardíaca/prevenção & controle , Miocárdio/enzimologia , NADPH Oxidases/deficiência , Peptidil Dipeptidase A/deficiência , Análise de Variância , Angiotensina I , Angiotensina II/administração & dosagem , Angiotensina II/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Pressão Sanguínea , Cardiomiopatia Dilatada/enzimologia , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/fisiopatologia , Modelos Animais de Doenças , Ativação Enzimática , Matriz Extracelular/metabolismo , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/patologia , NADPH Oxidases/genética , Estresse Oxidativo , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/genética , Fosforilação , Estresse Mecânico , Superóxidos/metabolismo , Fatores de Tempo , Função Ventricular Esquerda , Remodelação Ventricular
11.
Hypertension ; 57(2): 314-22, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21189404

RESUMO

Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase capable of metabolizing angiotensin (Ang) II into Ang 1 to 7. We hypothesized that ACE2 is a negative regulator of Ang II signaling and its adverse effects on the kidneys. Ang II infusion (1.5 mg/kg⁻¹/d⁻¹) for 4 days resulted in higher renal Ang II levels and increased nicotinamide adenine dinucleotide phosphate oxidase activity in ACE2 knockout (Ace2(-/y)) mice compared to wild-type mice. Expression of proinflammatory cytokines, interleukin-1ß and chemokine (C-C motif) ligand 5, were increased in association with greater activation of extracellular-regulated kinase 1/2 and increase of protein kinase C-α levels. These changes were associated with increased expression of fibrosis-associated genes (α-smooth muscle actin, transforming growth factor-ß, procollagen type Iα1) and increased protein levels of collagen I with histological evidence of increased tubulointerstitial fibrosis. Ang II-infused wild-type mice were then treated with recombinant human ACE2 (2 mg/kg⁻¹/d⁻¹, intraperitoneal). Daily treatment with recombinant human ACE2 reduced Ang II-induced pressor response and normalized renal Ang II levels and oxidative stress. These changes were associated with a suppression of Ang II-mediated activation of extracellular-regulated kinase 1/2 and protein kinase C pathway and Ang II-mediated renal fibrosis and T-lymphocyte-mediated inflammation. We conclude that loss of ACE2 enhances renal Ang II levels and Ang II-induced renal oxidative stress, resulting in greater renal injury, whereas recombinant human ACE2 prevents Ang II-induced hypertension, renal oxidative stress, and tubulointerstitial fibrosis. ACE2 is an important negative regulator of Ang II-induced renal disease and enhancing ACE2 action may have therapeutic potential for patients with kidney disease.


Assuntos
Angiotensina II/farmacologia , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Peptidil Dipeptidase A/metabolismo , Actinas/genética , Actinas/metabolismo , Angiotensina II/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Western Blotting , Colágeno/genética , Colágeno/metabolismo , Citocinas/genética , Citocinas/metabolismo , Feminino , Fibrose , Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso/metabolismo , NADPH Oxidases/metabolismo , Peptidil Dipeptidase A/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Circ Res ; 107(10): 1275-89, 2010 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-20847309

RESUMO

RATIONALE: Mechanotransduction and the response to biomechanical stress is a fundamental response in heart disease. Loss of phosphoinositide 3-kinase (PI3K)γ, the isoform linked to G protein-coupled receptor signaling, results in increased myocardial contractility, but the response to pressure overload is controversial. OBJECTIVE: To characterize molecular and cellular responses of the PI3Kγ knockout (KO) mice to biomechanical stress. METHODS AND RESULTS: In response to pressure overload, PI3KγKO mice deteriorated at an accelerated rate compared with wild-type mice despite increased basal myocardial contractility. These functional responses were associated with compromised phosphorylation of Akt and GSK-3α. In contrast, isolated single cardiomyocytes from banded PI3KγKO mice maintained their hypercontractility, suggesting compromised interaction with the extracellular matrix as the primary defect in the banded PI3KγKO mice. ß-Adrenergic stimulation increased cAMP levels with increased phosphorylation of CREB, leading to increased expression of cAMP-responsive matrix metalloproteinases (MMPs), MMP2, MT1-MMP, and MMP13 in cardiomyocytes and cardiofibroblasts. Loss of PI3Kγ resulted in increased cAMP levels with increased expression of MMP2, MT1-MMP, and MMP13 and increased MMP2 activation and collagenase activity in response to biomechanical stress. Selective loss of N-cadherin from the adhesion complexes in the PI3KγKO mice resulted in reduced cell adhesion. The ß-blocker propranolol prevented the upregulation of MMPs, whereas MMP inhibition prevented the adverse remodeling with both therapies, preventing the functional deterioration in banded PI3KγKO mice. In banded wild-type mice, long-term propranolol prevented the adverse remodeling and systolic dysfunction with preservation of the N-cadherin levels. CONCLUSIONS: The enhanced propensity to develop heart failure in the PI3KγKO mice is attributable to a cAMP-dependent upregulation of MMP expression and activity and disorganization of the N-cadherin/ß-catenin cell adhesion complex. ß-Blocker therapy prevents these changes thereby providing a novel mechanism of action for these drugs.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Cardiomegalia/enzimologia , Classe Ib de Fosfatidilinositol 3-Quinase/metabolismo , AMP Cíclico/metabolismo , Matriz Extracelular/metabolismo , Metaloproteinases da Matriz/metabolismo , Mecanotransdução Celular , Miocárdio/enzimologia , Remodelação Ventricular , Antagonistas Adrenérgicos beta/administração & dosagem , Animais , Fenômenos Biomecânicos , Cardiomegalia/tratamento farmacológico , Cardiomegalia/fisiopatologia , Adesão Celular , Células Cultivadas , Classe Ib de Fosfatidilinositol 3-Quinase/deficiência , Classe Ib de Fosfatidilinositol 3-Quinase/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Modelos Animais de Doenças , Fibroblastos/enzimologia , Quinase 3 da Glicogênio Sintase/metabolismo , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/prevenção & controle , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Mecanotransdução Celular/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Contração Miocárdica , Miocárdio/patologia , Miócitos Cardíacos/enzimologia , Fosforilação , Propranolol/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estresse Mecânico , Fatores de Tempo , Remodelação Ventricular/efeitos dos fármacos , beta Catenina/metabolismo
13.
Circulation ; 122(7): 717-28, 18 p following 728, 2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20679547

RESUMO

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is a pleiotropic monocarboxypeptidase capable of metabolizing several peptide substrates. We hypothesized that ACE2 is a negative regulator of angiotensin II (Ang II)-mediated signaling and its adverse effects on the cardiovascular system. METHODS AND RESULTS: Ang II infusion (1.5 mg x kg(-1) x d(-1)) for 14 days resulted in worsening cardiac fibrosis and pathological hypertrophy in ACE2 knockout (Ace2(-/y)) mice compared with wild-type (WT) mice. Daily treatment of Ang II-infused wild-type mice with recombinant human ACE2 (rhACE2; 2 mg x kg(-1) x d(-1) IP) blunted the hypertrophic response and expression of hypertrophy markers and reduced Ang II-induced superoxide production. Ang II-mediated myocardial fibrosis and expression of procollagen type I alpha 1, procollagen type III alpha 1, transforming growth factor-beta1, and fibronectin were also suppressed by rhACE2. Ang II-induced diastolic dysfunction was inhibited by rhACE2 in association with reduced plasma and myocardial Ang II and increased plasma Ang 1-7 levels. rhACE2 treatment inhibited Ang II-mediated activation of protein kinase C-alpha and protein kinase C-beta1 protein levels and phosphorylation of the extracellular signal-regulated 1/2, Janus kinase 2, and signal transducer and activator of transcription 3 signaling pathways in wild-type mice. A subpressor dose of Ang II (0.15 mg . kg(-1) . d(-1)) resulted in a milder phenotype that was strikingly attenuated by rhACE2 (2 mg x kg(-1) x d(-1) IP). In adult ventricular cardiomyocytes and cardiofibroblasts, Ang II-mediated superoxide generation, collagen production, and extracellular signal-regulated 1/2 signaling were inhibited by rhACE2 in an Ang 1-7-dependent manner. Importantly, rhACE2 partially prevented the development of dilated cardiomyopathy in pressure-overloaded wild-type mice. CONCLUSIONS: Elevated Ang II induced hypertension, myocardial hypertrophy, fibrosis, and diastolic dysfunction, which were exacerbated by ACE2 deficiency, whereas rhACE2 attenuated Ang II- and pressure-overload-induced adverse myocardial remodeling. Hence, ACE2 is an important negative regulator of Ang II-induced heart disease and suppresses adverse myocardial remodeling.


Assuntos
Cardiomegalia/enzimologia , Cardiomegalia/prevenção & controle , Regulação para Baixo/fisiologia , Hipertrofia Ventricular Esquerda/enzimologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Miocárdio/enzimologia , Miocárdio/patologia , Peptidil Dipeptidase A/deficiência , Angiotensina II/administração & dosagem , Angiotensina II/antagonistas & inibidores , Angiotensina II/biossíntese , Enzima de Conversão de Angiotensina 2 , Animais , Células CHO , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Células Cultivadas , Cadeia alfa 1 do Colágeno Tipo I , Cricetinae , Cricetulus , Fibrose , Humanos , Hipertrofia Ventricular Esquerda/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peptidil Dipeptidase A/administração & dosagem , Peptidil Dipeptidase A/fisiologia , Proteínas Recombinantes/administração & dosagem
14.
Circ Heart Fail ; 2(5): 446-55, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19808375

RESUMO

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase that metabolizes Ang II into Ang 1-7, thereby functioning as a negative regulator of the renin-angiotensin system. We hypothesized that ACE2 deficiency may compromise the cardiac response to myocardial infarction (MI). METHODS AND RESULTS: In response to MI (induced by left anterior descending artery ligation), there was a persistent increase in ACE2 protein in the infarct zone in wild-type mice, whereas loss of ACE2 enhanced the susceptibility to MI, with increased mortality, infarct expansion, and adverse ventricular remodeling characterized by ventricular dilation and systolic dysfunction. In ACE2-deficient hearts, elevated myocardial levels of Ang II and decreased levels of Ang 1-7 in the infarct-related zone was associated with increased production of reactive oxygen species. ACE2 deficiency leads to increased matrix metalloproteinase (MMP) 2 and MMP9 levels with MMP2 activation in the infarct and peri-infarct regions, as well as increased gelatinase activity leading to a disrupted extracellular matrix structure after MI. Loss of ACE2 also leads to increased neutrophilic infiltration in the infarct and peri-infarct regions, resulting in upregulation of inflammatory cytokines, interferon-gamma, interleukin-6, and the chemokine, monocyte chemoattractant protein-1, as well as increased phosphorylation of ERK1/2 and JNK1/2 signaling pathways. Treatment of Ace2(-)(/y)-MI mice with irbesartan, an AT1 receptor blocker, reduced nicotinamide-adenine dinucleotide phosphate oxidase activity, infarct size, MMP activation, and myocardial inflammation, ultimately resulting in improved post-MI ventricular function. CONCLUSIONS: We conclude that loss of ACE2 facilitates adverse post-MI ventricular remodeling by potentiation of Ang II effects by means of the AT1 receptors, and supplementing ACE2 can be a potential therapy for ischemic heart disease.


Assuntos
Infarto do Miocárdio/enzimologia , Miocárdio/enzimologia , Peptidil Dipeptidase A/deficiência , Remodelação Ventricular , Adaptação Fisiológica , Angiotensina I , Angiotensina II/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Enzima de Conversão de Angiotensina 2 , Animais , Compostos de Bifenilo/farmacologia , Modelos Animais de Doenças , Ativação Enzimática , Mediadores da Inflamação/metabolismo , Irbesartana , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Estresse Oxidativo , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/genética , Fosforilação , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Superóxidos/metabolismo , Tetrazóis/farmacologia , Fatores de Tempo , Ultrassonografia , Remodelação Ventricular/efeitos dos fármacos
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