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1.
J Am Coll Cardiol ; 75(10): 1128-1141, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32164886

RESUMO

BACKGROUND: More data regarding effects of glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes (T2D) and heart failure (HF) are required. OBJECTIVES: The purpose of this study was to investigate the effects of liraglutide on cardiovascular events and mortality in LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results) participants, by HF history. METHODS: In the multinational, double-blind, randomized LEADER trial, 9,340 patients with T2D and high cardiovascular risk were assigned 1:1 to liraglutide (1.8 mg daily or maximum tolerated dose up to 1.8 mg daily) or placebo plus standard care, and followed for 3.5 to 5 years. New York Heart Association (NYHA) functional class IV HF was an exclusion criterion. The primary composite major adverse cardiovascular events outcome was time to first occurrence of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. Post hoc Cox regression analyses of outcomes by baseline HF history were conducted. RESULTS: At baseline, 18% of patients had a history of NYHA functional class I to III HF (liraglutide: n = 835 of 4,668; placebo: n = 832 of 4,672). Effects of liraglutide versus placebo on major adverse cardiovascular events were consistent in patients with (hazard ratio [HR]: 0.81 [95% confidence interval (CI): 0.65 to 1.02]) and without (HR: 0.88 [95% CI: 0.78 to 1.00]) a history of HF (p interaction = 0.53). In both subgroups, fewer deaths were observed with liraglutide (HR: 0.89 [95% CI: 0.70 to 1.14] with HF; HR: 0.83 [95% CI: 0.70 to 0.97] without HF; p interaction = 0.63) versus placebo. No increased risk of HF hospitalization was observed with liraglutide, regardless of HF history (HR: 0.98 [95% CI: 0.75 to 1.28] with HF; HR: 0.78 [95% CI: 0.61 to 1.00] without HF; p interaction = 0.22). Effects of liraglutide on the composite of HF hospitalization or cardiovascular death were consistent in patients with (HR: 0.92 [95% CI: 0.74 to 1.15]) and without (HR: 0.77 [95% CI: 0.65 to 0.91]) a history of HF (p interaction = 0.19). CONCLUSIONS: Based on these findings, liraglutide should be considered suitable for patients with T2D with or without a history of NYHA functional class I to III HF. (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results [LEADER]; NCT01179048).

2.
Diabetes Obes Metab ; 22(3): 442-451, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31903692

RESUMO

AIM: To investigate the effects of semaglutide versus comparators on major adverse cardiovascular events (MACE: cardiovascular [CV] death, nonfatal myocardial infarction [MI] and nonfatal stroke) and hospitalization for heart failure (HF) in the SUSTAIN (subcutaneous semaglutide) and PIONEER (oral semaglutide) trials across subgroups of varying CV risk. METHODS: Post hoc analyses of individual patient-level data combined from SUSTAIN 6 and PIONEER 6 were performed to assess MACE and HF. MACE were analysed in subjects with and without: established CV disease and/or chronic kidney disease; prior MI or stroke; and prior HF. MACE in the SUSTAIN and PIONEER glycaemic efficacy trials were also assessed. RESULTS: In SUSTAIN 6 and PIONEER 6 combined, the hazard ratio (HR) for effect of semaglutide versus placebo on overall MACE was 0.76 (95% CI 0.62, 0.92), which was mainly driven by the effect on nonfatal stroke (HR 0.65 [95% CI 0.43, 0.97]). The HR for hospitalization for HF was 1.03 (95% CI 0.75, 1.40). The HRs for MACE were <1.0 in all subgroups, except for those with prior HF (HR 1.06 [95% CI 0.72, 1.57]); P-values for interaction of subgroup on treatment effect were >0.05, except for HF (0.046). In the combined glycaemic efficacy trials, the HR for effect of semaglutide versus comparators on MACE was 0.85 (95% CI 0.55, 1.33). CONCLUSIONS: In SUSTAIN and PIONEER combined, glucagon-like peptide-1 analogue semaglutide showed consistent effects on MACE versus comparators across varying CV risk. No effect of semaglutide on MACE was observed in subjects with prior HF.

3.
J Clin Invest ; 130(3): 1392-1404, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31985487

RESUMO

Mechanisms mediating the cardioprotective actions of glucagon-like peptide 1 (GLP-1) were unknown. Here, we show in both ex vivo and in vivo models of ischemic injury that treatment with GLP-1(28-36), a neutral endopeptidase-generated (NEP-generated) metabolite of GLP-1, was as cardioprotective as GLP-1 and was abolished by scrambling its amino acid sequence. GLP-1(28-36) enters human coronary artery endothelial cells (caECs) through macropinocytosis and acts directly on mouse and human coronary artery smooth muscle cells (caSMCs) and caECs, resulting in soluble adenylyl cyclase Adcy10-dependent (sAC-dependent) increases in cAMP, activation of protein kinase A, and cytoprotection from oxidative injury. GLP-1(28-36) modulates sAC by increasing intracellular ATP levels, with accompanying cAMP accumulation lost in sAC-/- cells. We identify mitochondrial trifunctional protein-α (MTPα) as a binding partner of GLP-1(28-36) and demonstrate that the ability of GLP-1(28-36) to shift substrate utilization from oxygen-consuming fatty acid metabolism toward oxygen-sparing glycolysis and glucose oxidation and to increase cAMP levels is dependent on MTPα. NEP inhibition with sacubitril blunted the ability of GLP-1 to increase cAMP levels in coronary vascular cells in vitro. GLP-1(28-36) is a small peptide that targets novel molecular (MTPα and sAC) and cellular (caSMC and caEC) mechanisms in myocardial ischemic injury.

4.
Cardiovasc Diabetol ; 18(1): 156, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729990

RESUMO

BACKGROUND: Heart failure (HF) is a common cardiovascular complication of type 2 diabetes (T2D). This secondary analysis investigated baseline factors and treatment differences associated with risk of hospitalization for HF (hHF), and the possible association between severe hypoglycemia and hHF. METHODS: DEVOTE was a treat-to-target, double-blind cardiovascular outcomes trial in patients (n = 7637) with T2D and high cardiovascular risk randomized to insulin degludec (degludec) or insulin glargine 100 units/mL (glargine U100). The main endpoint of this secondary analysis was time to first hHF (standardized MedDRA Query definition). Severe hypoglycemia was adjudicated (American Diabetes Association definition). The main endpoint and the temporal association between severe hypoglycemia and hHF were analyzed with a Cox proportional hazards regression model. Predictors of time to first hHF were identified using baseline variables. RESULTS: Overall, 372 (4.9%) patients experienced hHF (550 events). There was no significant difference in the risk of hHF between treatments (hazard ratio [HR] 0.88 [0.72;1.08]95% CI, p = 0.227). Prior HF (HR 4.89 [3.90;6.14]95% CI, p ≤ 0.0001) was the strongest predictor of future hHF events. The risk of hHF significantly increased after (HR 2.2), and within a week after (HR 11.1), experiencing a severe hypoglycemic episode compared with before an episode. CONCLUSIONS: In patients with T2D and high cardiovascular risk there were no treatment differences in terms of hHF. Prior HF was the strongest predictor of future hHF events, and there was an association between severe hypoglycemia and subsequent hHF. Further research should evaluate whether the risk of hHF can be modified by treatments aimed at reducing hypoglycemia. Trial Registration NCT01959529.

6.
Circulation ; 140(18): 1463-1476, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31524498

RESUMO

BACKGROUND: Outcome trials in patients with type 2 diabetes mellitus have demonstrated reduced hospitalizations for heart failure (HF) with sodium-glucose co-transporter-2 inhibitors. However, few of these patients had HF, and those that did were not well-characterized. Thus, the effects of sodium-glucose co-transporter-2 inhibitors in patients with established HF with reduced ejection fraction, including those with and without type 2 diabetes mellitus, remain unknown. METHODS: DEFINE-HF (Dapagliflozin Effects on Biomarkers, Symptoms and Functional Status in Patients with HF with Reduced Ejection Fraction) was an investigator-initiated, multi-center, randomized controlled trial of HF patients with left ventricular ejection fraction ≤40%, New York Heart Association (NYHA) class II-III, estimated glomerular filtration rate ≥30 mL/min/1.73m2, and elevated natriuretic peptides. In total, 263 patients were randomized to dapagliflozin 10 mg daily or placebo for 12 weeks. Dual primary outcomes were (1) mean NT-proBNP (N-terminal pro b-type natriuretic peptide) and (2) proportion of patients with ≥5-point increase in HF disease-specific health status on the Kansas City Cardiomyopathy Questionnaire overall summary score, or a ≥20% decrease in NT-proBNP. RESULTS: Patient characteristics reflected stable, chronic HF with reduced ejection fraction with high use of optimal medical therapy. There was no significant difference in average 6- and 12-week adjusted NT-proBNP with dapagliflozin versus placebo (1133 pg/dL (95% CI 1036-1238) vs 1191 pg/dL (95% CI 1089-1304), P=0.43). For the second dual-primary outcome of a meaningful improvement in Kansas City Cardiomyopathy Questionnaire overall summary score or NT-proBNP, 61.5% of dapagliflozin-treated patients met this end point versus 50.4% with placebo (adjusted OR 1.8, 95% CI 1.03-3.06, nominal P=0.039). This was attributable to both higher proportions of patients with ≥5-point improvement in Kansas City Cardiomyopathy Questionnaire overall summary score (42.9 vs 32.5%, adjusted OR 1.73, 95% CI 0.98-3.05), and ≥20% reduction in NT-proBNP (44.0 vs 29.4%, adjusted OR 1.9, 95% CI 1.1-3.3) by 12 weeks. Results were consistent among patients with or without type 2 diabetes mellitus, and other prespecified subgroups (all P values for interaction=NS). CONCLUSIONS: In patients with heart failure and reduced ejection fraction, use of dapagliflozin over 12 weeks did not affect mean NT-proBNP but increased the proportion of patients experiencing clinically meaningful improvements in HF-related health status or natriuretic peptides. Benefits of dapagliflozin on clinically meaningful HF measures appear to extend to patients without type 2 diabetes mellitus. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02653482.

7.
N Engl J Med ; 381(9): 841-851, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31185157

RESUMO

BACKGROUND: Establishing cardiovascular safety of new therapies for type 2 diabetes is important. Safety data are available for the subcutaneous form of the glucagon-like peptide-1 receptor agonist semaglutide but are needed for oral semaglutide. METHODS: We assessed cardiovascular outcomes of once-daily oral semaglutide in an event-driven, randomized, double-blind, placebo-controlled trial involving patients at high cardiovascular risk (age of ≥50 years with established cardiovascular or chronic kidney disease, or age of ≥60 years with cardiovascular risk factors only). The primary outcome in a time-to-event analysis was the first occurrence of a major adverse cardiovascular event (death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke). The trial was designed to rule out 80% excess cardiovascular risk as compared with placebo (noninferiority margin of 1.8 for the upper boundary of the 95% confidence interval for the hazard ratio for the primary outcome). RESULTS: A total of 3183 patients were randomly assigned to receive oral semaglutide or placebo. The mean age of the patients was 66 years; 2695 patients (84.7%) were 50 years of age or older and had cardiovascular or chronic kidney disease. The median time in the trial was 15.9 months. Major adverse cardiovascular events occurred in 61 of 1591 patients (3.8%) in the oral semaglutide group and 76 of 1592 (4.8%) in the placebo group (hazard ratio, 0.79; 95% confidence interval [CI], 0.57 to 1.11; P<0.001 for noninferiority). Results for components of the primary outcome were as follows: death from cardiovascular causes, 15 of 1591 patients (0.9%) in the oral semaglutide group and 30 of 1592 (1.9%) in the placebo group (hazard ratio, 0.49; 95% CI, 0.27 to 0.92); nonfatal myocardial infarction, 37 of 1591 patients (2.3%) and 31 of 1592 (1.9%), respectively (hazard ratio, 1.18; 95% CI, 0.73 to 1.90); and nonfatal stroke, 12 of 1591 patients (0.8%) and 16 of 1592 (1.0%), respectively (hazard ratio, 0.74; 95% CI, 0.35 to 1.57). Death from any cause occurred in 23 of 1591 patients (1.4%) in the oral semaglutide group and 45 of 1592 (2.8%) in the placebo group (hazard ratio, 0.51; 95% CI, 0.31 to 0.84). Gastrointestinal adverse events leading to discontinuation of oral semaglutide or placebo were more common with oral semaglutide. CONCLUSIONS: In this trial involving patients with type 2 diabetes, the cardiovascular risk profile of oral semaglutide was not inferior to that of placebo. (Funded by Novo Nordisk; PIONEER 6 ClinicalTrials.gov number, NCT02692716.).


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Hipoglicemiantes/administração & dosagem , Administração Oral , Idoso , Diabetes Mellitus Tipo 2/complicações , Método Duplo-Cego , Feminino , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Hemoglobina A Glicada/análise , Humanos , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Risco
8.
Cell Rep ; 27(8): 2304-2312.e6, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31116977

RESUMO

Mechanisms that govern transcriptional regulation of inflammation in atherosclerosis remain largely unknown. Here, we identify the nuclear transcription factor c-Myb as an important mediator of atherosclerotic disease in mice. Atherosclerosis-prone animals fed a diet high in cholesterol exhibit increased levels of c-Myb in the bone marrow. Use of mice that either harbor a c-Myb hypomorphic allele or where c-Myb has been preferentially deleted in B cell lineages revealed that c-Myb potentiates atherosclerosis directly through its effects on B lymphocytes. Reduced c-Myb activity prevents the expansion of atherogenic B2 cells yet associates with increased numbers of IgM-producing antibody-secreting cells (IgM-ASCs) and elevated levels of atheroprotective oxidized low-density lipoprotein (OxLDL)-specific IgM antibodies. Transcriptional profiling revealed that c-Myb has a limited effect on B cell function but is integral in maintaining B cell progenitor populations in the bone marrow. Thus, targeted disruption of c-Myb beneficially modulates the complex biology of B cells in cardiovascular disease.

9.
Nat Immunol ; 20(5): 664, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30862954

RESUMO

In the version of this article initially published, the equal contribution of the third author was omitted. The footnote links for that author should be "Sara Nejat1,11" and the correct statement is as follows: "11These authors contributed equally: Sarah A. Dick, Jillian A. Macklin, Sara Nejat." The error has been corrected in the HTML and PDF versions of the article.

10.
Hypertension ; 73(3): 561-570, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30636551

RESUMO

The proto-oncogene c-myb (and corresponding nuclear transcription factor, c-Myb) regulates the proliferation and differentiation of hematologic and vascular smooth muscle cells; however, the role of c-Myb in blood pressure regulation is unknown. Here, we show that mice homozygous for a hypomorphic c-myb allele ( c-myb h/h) conferring reduced c-Myb activity manifest reduced peripheral blood and kidney B220+ B-cells and have decreased systolic (104±2 versus 120±1 mm Hg; P<0.0001) and diastolic blood pressure (71±2 versus 83±1 mm Hg; P<0.0001) compared with WT (wild type) mice. Additionally, c-myb h/h mice had lower susceptibility to deoxycorticosterone acetate-salt experimental hypertension. Although cardiac (echocardiography) and resistance artery (perfusion myography) functions were normal, metabolic cage studies revealed that c-myb h/h mice had increased 24-hour urine output and sodium excretion versus WT. Reconstitution of WT mice with c-myb h/h bone marrow transplant and chimeric bone marrow transplant using mice lacking B-cells ( J H T; h/h>WT and h/h:J H T>WT, respectively) decreased blood pressure and increased 24-hour urine output compared with controls ( WT>WT; WT:J H T>WT). J H T mice also had decreased systolic (103±2 versus 115±1 mm Hg; P<0.0001) and diastolic blood pressure (71±2 versus 79±1; P<0.01) and increased 24-hour urine output versus WT. Real-time quantitative reverse transcription polymerase chain reaction of kidney medulla revealed reduced V2R (vasopressin receptor 2) expression in c-myb h/h and J H T mice. These data implicate B-cells in the regulation of V2R and its associated effects on salt and water handling and blood pressure homeostasis.


Assuntos
Linfócitos B/metabolismo , Pressão Sanguínea/fisiologia , Hipertensão/imunologia , Miócitos de Músculo Liso/metabolismo , Animais , Linfócitos B/patologia , Diferenciação Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/patologia , Proteínas Proto-Oncogênicas c-myb/biossíntese , Proteínas Proto-Oncogênicas c-myb/genética , RNA/genética
11.
Diabetes Obes Metab ; 21(3): 499-508, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30284349

RESUMO

AIMS: To assess the cardiovascular (CV) safety of oral semaglutide, the first tablet formulation of a glucagon-like peptide-1 receptor agonist. MATERIALS AND METHODS: PIONEER 6 is a multinational, randomized, placebo-controlled, double-blind trial in patients with type 2 diabetes at high risk of CV events (defined as being aged ≥50 years and having established CV disease [CVD] or moderate [stage 3] chronic kidney disease [CKD], or being aged ≥60 years with ≥1 other CV risk factor). Patients were randomized to once-daily oral semaglutide (up to 14 mg) or placebo added to standard of care. The primary composite endpoint is time to first occurrence of CV death or non-fatal myocardial infarction or non-fatal stroke. The primary hypothesis was to exclude an excess in CV risk with oral semaglutide by assessing non-inferiority versus placebo for the primary endpoint (non-inferiority margin of 1.8 for the upper boundary of the 95% confidence interval of the hazard ratio). PIONEER 6 is event-driven, with follow-up continuing until accrual of at least 122 primary outcome events. There is no pre-defined minimal duration. RESULTS: Overall, 3183 patients have been enrolled (mean age 66.1 years, 31.6% females) in 214 sites across 21 countries. At baseline, the mean duration of diabetes was 14.9 years, mean glycated haemoglobin concentration was 66 mmol/mol (8.2%), and 84.6% of patients had established CVD/moderate CKD. CONCLUSIONS: PIONEER 6 will provide evidence regarding the CV safety of oral semaglutide in patients with type 2 diabetes and high CV risk.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Sistema Cardiovascular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeos Semelhantes ao Glucagon/administração & dosagem , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/prevenção & controle , Método Duplo-Cego , Feminino , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Masculino , Metformina/administração & dosagem , Metformina/efeitos adversos , Pessoa de Meia-Idade , Placebos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia
12.
Nat Immunol ; 20(1): 29-39, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30538339

RESUMO

Macrophages promote both injury and repair after myocardial infarction, but discriminating functions within mixed populations remains challenging. Here we used fate mapping, parabiosis and single-cell transcriptomics to demonstrate that at steady state, TIMD4+LYVE1+MHC-IIloCCR2- resident cardiac macrophages self-renew with negligible blood monocyte input. Monocytes partially replaced resident TIMD4-LYVE1-MHC-IIhiCCR2- macrophages and fully replaced TIMD4-LYVE1-MHC-IIhiCCR2+ macrophages, revealing a hierarchy of monocyte contribution to functionally distinct macrophage subsets. Ischemic injury reduced TIMD4+ and TIMD4- resident macrophage abundance, whereas CCR2+ monocyte-derived macrophages adopted multiple cell fates within infarcted tissue, including those nearly indistinguishable from resident macrophages. Recruited macrophages did not express TIMD4, highlighting the ability of TIMD4 to track a subset of resident macrophages in the absence of fate mapping. Despite this similarity, inducible depletion of resident macrophages using a Cx3cr1-based system led to impaired cardiac function and promoted adverse remodeling primarily within the peri-infarct zone, revealing a nonredundant, cardioprotective role of resident cardiac macrophages.


Assuntos
Macrófagos/fisiologia , Infarto do Miocárdio/imunologia , Miocárdio/patologia , Animais , Receptor 1 de Quimiocina CX3C/metabolismo , Diferenciação Celular , Linhagem da Célula , Autorrenovação Celular , Perfilação da Expressão Gênica , Antígenos de Histocompatibilidade Classe II/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Parabiose , Receptores CCR2/genética , Receptores CCR2/metabolismo , Análise de Célula Única , Remodelação Ventricular , Proteínas de Transporte Vesicular/metabolismo
13.
PLoS One ; 13(8): e0202778, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30169548

RESUMO

BACKGROUND: MicroRNAs (miR) are small non-coding RNAs that regulate diverse biological functions. The bicistronic gene miR-143/145 determines cell fate and phenotype of vascular smooth muscle cells (VSMC), in part, by destabilizing Elk-1 mRNA. The transcription factor c-Myb also regulates differentiation and proliferation of VSMC, and here we test whether these effects may be mediated by miR-143/145. METHODS & RESULTS: Flow cytometry of cardiovascular-directed d3.75 embryoid bodies (EBs) isolated smooth muscle progenitors with specific cell surface markers. In c-myb knockout (c-myb -/-) EB, these progenitors manifest low levels of miR-143 (19%; p<0.05) and miR-145 (6%; p<0.01) expression as compared to wild-type (wt) EB. Primary VSMC isolated from transgenic mice with diminished expression (c-myblx/lx) or reduced activity (c-mybh/h) of c-Myb also manifest low levels of miR-143 (c-myblx/lx: 50%; c-mybh/h: 41%), and miR-145 (c-myblx/lx: 49%; c-mybh/h: 56%), as compared to wt (P<0.05). Sequence alignment identified four putative c-Myb binding sites (MBS1-4) in the proximal promoter (PP) of the miR-143/145 gene. PP-reporter constructs revealed that point mutations in MBS1 and MBS4 abrogated c-Myb-dependent transcription from the miR-143/145 PP (P<0.01). Chromatin immunoprecipitation (ChIP) revealed preferential c-Myb binding at MBS4 (p<0.001). By conjugating Elk-1 3'-untranslated region (UTR) to a reporter and co-transducing wt VSMC with this plus a miR-143-antagomir, and co-transducing c-myblx/lx VSMC with this plus a miR-143-mimic, we demonstrate that c-Myb's ability to repress Elk-1 is mediated by miR-143. CONCLUSION: c-Myb regulates VSMC gene expression by transcriptional activation of miR-143/145.


Assuntos
MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-myb/metabolismo , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Sítios de Ligação , Células Cultivadas , Imunoprecipitação da Cromatina , Camundongos , Camundongos Knockout , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Mutação Puntual , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myb/genética , Ativação Transcricional/genética , Proteínas Elk-1 do Domínio ets/genética , Proteínas Elk-1 do Domínio ets/metabolismo
14.
Curr Diab Rep ; 18(7): 45, 2018 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-29886514

RESUMO

PURPOSE OF REVIEW: In addition to their effects on glycemic control, two specific classes of relatively new anti-diabetic drugs, namely the sodium glucose co-transporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) have demonstrated reduced rates of major adverse cardiovascular events (MACE) in subjects with type 2 diabetes (T2D) at high risk for cardiovascular disease (CVD). This review summarizes recent experimental results that inform putative molecular mechanisms underlying these benefits. RECENT FINDINGS: SGLT2i and GLP-1RA exert cardiovascular effects by targeting in both common and distinctive ways (A) several mediators of macro- and microvascular pathophysiology: namely (A1) inflammation and atherogenesis, (A2) oxidative stress-induced endothelial dysfunction, (A3) vascular smooth muscle cell reactive oxygen species (ROS) production and proliferation, and (A4) thrombosis. These agents also exhibit (B) hemodynamic effects through modulation of (B1) natriuresis/diuresis and (B2) the renin-angiotensin-aldosterone system. This review highlights that while GLP-1RA exert direct effects on vascular (endothelial and smooth muscle) cells, the effects of SGLT2i appear to include the activation of signaling pathways that prevent adverse vascular remodeling. Both SGLT2i and GLP-1RA confer hemodynamic effects that counter adverse cardiac remodeling.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Cardiotônicos/farmacologia , Sistema Cardiovascular/patologia , Sistema Cardiovascular/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos
15.
Stem Cells Dev ; 27(13): 888-897, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717623

RESUMO

Sca-1+ progenitor cells in the adult mouse aorta are known to generate vascular smooth muscle cells (VSMCs), but their embryological origins and temporal abundance are not known. Using tamoxifen-inducible Myf5-CreER mice, we demonstrate that Sca-1+ adult aortic cells arise from the somitic mesoderm beginning at E8.5 and continue throughout somitogenesis. Myf5 lineage-derived Sca-1+ cells greatly expand in situ, starting at 4 weeks of age, and become a major source of aortic Sca-1+ cells by 6 weeks of age. Myf5-derived adult aortic cells are capable of forming multicellular sphere-like structures in vitro and express the pluripotency marker Sox2. Exposure to transforming growth factor-ß3 induces these spheres to differentiate into calponin-expressing VSMCs. Pulse-chase experiments using tamoxifen-inducible Sox2-CreERT2 mice at 8 weeks of age demonstrate that ∼35% of all adult aortic Sca-1+ cells are derived from Sox2+ cells. The present study demonstrates that aortic Sca-1+ progenitor cells are derived from the somitic mesoderm formed at the earliest stages of somitogenesis and from Sox2-expressing progenitors in adult mice.


Assuntos
Antígenos Ly/metabolismo , Aorta/metabolismo , Linhagem da Célula/fisiologia , Proteínas de Membrana/metabolismo , Mesoderma/metabolismo , Somitos/metabolismo , Células-Tronco/metabolismo , Animais , Diferenciação Celular/fisiologia , Camundongos , Miócitos de Músculo Liso/metabolismo , Fator Regulador Miogênico 5/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fator de Crescimento Transformador beta3/metabolismo
16.
Clin Sci (Lond) ; 132(6): 641-654, 2018 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-29487197

RESUMO

Background: Heart failure (HF) is associated with reduced expression of plasma membrane Ca2+-ATPase 4 (PMCA4). Cardiac-specific overexpression of human PMCA4b in mice inhibited nNOS activity and reduced cardiac hypertrophy by inhibiting calcineurin. Here we examine temporally regulated cardiac-specific overexpression of hPMCA4b in mouse models of myocardial ischemia reperfusion injury (IRI) ex vivo, and HF following experimental myocardial infarction (MI) in vivoMethods and results: Doxycycline-regulated cardiomyocyte-specific overexpression and activity of hPMCA4b produced adaptive changes in expression levels of Ca2+-regulatory genes, and induced hypertrophy without significant differences in Ca2+ transients or diastolic Ca2+ concentrations. Total cardiac NOS and nNOS-specific activities were reduced in mice with cardiac overexpression of hPMCA4b while nNOS, eNOS and iNOS protein levels did not differ. hMPCA4b-overexpressing mice also exhibited elevated systolic blood pressure vs. controls, with increased contractility and lusitropy in vivo In isolated hearts undergoing IRI, hPMCA4b overexpression was cardioprotective. NO donor-treated hearts overexpressing hPMCA4b showed reduced LVDP and larger infarct size versus vehicle-treated hearts undergoing IRI, demonstrating that the cardioprotective benefits of hPMCA4b-repressed nNOS are lost by restoring NO availability. Finally, both pre-existing and post-MI induction of hPMCA4b overexpression reduced infarct expansion and improved survival from HF.Conclusions: Cardiac PMCA4b regulates nNOS activity, cardiac mass and contractility, such that PMCA4b overexpression preserves cardiac function following IRI, heightens cardiac performance and limits infarct progression, cardiac hypertrophy and HF, even when induced late post-MI. These data identify PMCA4b as a novel therapeutic target for IRI and HF.


Assuntos
Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/enzimologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Animais , Sinalização do Cálcio , Modelos Animais de Doenças , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/prevenção & controle , Humanos , Hipertrofia Ventricular Esquerda/enzimologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Preparação de Coração Isolado , Camundongos Transgênicos , Contração Miocárdica , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Regulação para Cima , Função Ventricular Esquerda , Pressão Ventricular
17.
J Nucl Cardiol ; 25(3): 724-737, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28948540

RESUMO

BACKGROUND: Transient ischemic dilatation (TID) of the left ventricle is a potential marker of high risk obstructive coronary artery disease on stress myocardial perfusion imaging (MPI). There is, however, interstudy variation in the diagnostic performance of TID for identification of severe and extensive coronary disease anatomy, and varied prognostic implications in the published literature. METHODS: We searched MEDLINE, EMBASE, and COCHRANE databases for studies where TID was compared with invasive or CT coronary angiography for evaluation of coronary artery stenosis. Two reviewers independently evaluated and abstracted data from each study. A bivariate random effects model was used to derive pooled sensitivities and specificities, in order to account for correlation between TID in MPI and anatomic disease severity. RESULTS: A total of 525 articles were reviewed, of which 51 met inclusion criteria. Thirty-one studies contributed to the analysis, representing a total of 2037 patients in the diagnostic meta-analysis and 9003 patients in the review of prognosis. The ratio above which TID was deemed present ranged from 1.13 to 1.38. Pooled sensitivity was 44% (95% CI 30%-60%) and specificity was 88% (95% CI 83%-92%) for the detection of extensive or severe anatomic coronary artery disease. Analysis of outcome data demonstrated increased cardiac event rates in patients with TID and an abnormal MPI. In otherwise normal perfusion, TID is an indicator of poor prognosis in patients with diabetes and/or a history of coronary disease. CONCLUSIONS: Among patients undergoing MPI, the presence of TID is specific for the detection of extensive or severe coronary artery disease.


Assuntos
Ventrículos do Coração/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Dilatação Patológica , Ventrículos do Coração/patologia , Humanos , Isquemia Miocárdica/patologia , Prognóstico
18.
Am J Physiol Heart Circ Physiol ; 314(1): H31-H44, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28986362

RESUMO

Doxorubicin is a widely used chemotherapeutic with deleterious cardiotoxic side effects. HDL has been shown to protect cardiomyocytes in vitro against doxorubicin-induced apoptosis. Scavenger receptor class B type 1 (SR-B1), a high-affinity HDL receptor, mediates cytoprotective signaling by HDL through Akt. Here, we assessed whether increased HDL levels protect against doxorubicin-induced cardiotoxicity in vivo and in cardiomyocytes in culture and explored the intracellular signaling mechanisms involved, particularly the role of SR-B1. Transgenic mice with increased HDL levels through overexpression of human apolipoprotein A1 (apoA1Tg/Tg) and wild-type mice (apoA1+/+) with normal HDL levels were treated repeatedly with doxorubicin. After treatment, apoA1+/+ mice displayed cardiac dysfunction, as evidenced by reduced left ventricular end-systolic pressure and +dP/d t, and histological analysis revealed cardiomyocyte atrophy and increased cardiomyocyte apoptosis after doxorubicin treatment. In contrast, apoA1Tg/Tg mice were protected against doxorubicin-induced cardiac dysfunction and cardiomyocyte atrophy and apoptosis. When SR-B1 was knocked out, however, overexpression of apoA1 did not protect against doxorubicin-induced cardiotoxicity. Using primary neonatal mouse cardiomyocytes and human immortalized ventricular cardiomyocytes in combination with genetic knockout, inhibitors, or siRNA-mediated knockdown, we demonstrated that SR-B1 is required for HDL-mediated protection of cardiomyocytes against doxorubicin-induced apoptosis in vitro via a pathway involving phosphatidylinositol 3-kinase and Akt1/2. Our findings provide proof of concept that raising apoA1 to supraphysiological levels can dramatically protect against doxorubicin-induced cardiotoxicity via a pathway that is mediated by SR-B1 and involves Akt1/2 activation in cardiomyocytes. NEW & NOTEWORTHY We have identified an important role for the scavenger receptor class B type 1 in facilitating high-density lipoprotein-mediated protection of cardiomyocytes against stress-induced apoptosis and shown that increasing plasma high-density lipoprotein protects against the deleterious side effects of the chemotherapeutic and cardiotoxic drug doxorubicin.


Assuntos
Cardiomiopatias/prevenção & controle , Doxorrubicina , Lipoproteínas HDL/metabolismo , Miócitos Cardíacos/enzimologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Depuradores Classe B/metabolismo , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Apolipoproteína A-I/genética , Apolipoproteína A-I/metabolismo , Apoptose , Atrofia , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/enzimologia , Cardiomiopatias/fisiopatologia , Cardiotoxicidade , Linhagem Celular , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/patologia , Receptores Depuradores Classe B/deficiência , Receptores Depuradores Classe B/genética , Transdução de Sinais , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/enzimologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda
19.
Immunity ; 47(5): 974-989.e8, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29166591

RESUMO

Innate and adaptive immune cells modulate heart failure pathogenesis during viral myocarditis, yet their identities and functions remain poorly defined. We utilized a combination of genetic fate mapping, parabiotic, transcriptional, and functional analyses and demonstrated that the heart contained two major conventional dendritic cell (cDC) subsets, CD103+ and CD11b+, which differentially relied on local proliferation and precursor recruitment to maintain their tissue residency. Following viral infection of the myocardium, cDCs accumulated in the heart coincident with monocyte infiltration and loss of resident reparative embryonic-derived cardiac macrophages. cDC depletion abrogated antigen-specific CD8+ T cell proliferative expansion, transforming subclinical cardiac injury to overt heart failure. These effects were mediated by CD103+ cDCs, which are dependent on the transcription factor BATF3 for their development. Collectively, our findings identified resident cardiac cDC subsets, defined their origins, and revealed an essential role for CD103+ cDCs in antigen-specific T cell responses during subclinical viral myocarditis.


Assuntos
Antígenos CD/análise , Infecções por Cardiovirus/complicações , Células Dendríticas/imunologia , Vírus da Encefalomiocardite , Insuficiência Cardíaca/prevenção & controle , Cadeias alfa de Integrinas/análise , Miocardite/complicações , Animais , Antígeno CD11b/análise , Linfócitos T CD8-Positivos/imunologia , Infecções por Cardiovirus/imunologia , Movimento Celular , Feminino , Hematopoese , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocardite/imunologia , Receptores CCR2/fisiologia
20.
Infect Immun ; 85(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28674030

RESUMO

Artesunate remains the mainstay of treatment for cerebral malaria, but it is less effective in later stages of disease when the host inflammatory response and blood-brain barrier integrity dictate clinical outcomes. Nitric oxide (NO) is an important regulator of inflammation and microvascular integrity, and impaired NO bioactivity is associated with fatal outcomes in malaria. Endogenous NO bioactivity in mammals is largely mediated by S-nitrosothiols (SNOs). Based on these observations, we hypothesized that animals deficient in the SNO-metabolizing enzyme, S-nitrosoglutathione reductase (GSNOR), which exhibit enhanced S-nitrosylation, would have improved outcomes in a preclinical model of cerebral malaria. GSNOR knockout (KO) mice infected with Plasmodium berghei ANKA had significantly delayed mortality compared to WT animals (P < 0.0001), despite higher parasite burdens (P < 0.01), and displayed markedly enhanced survival versus the wild type (WT) when treated with the antimalarial drug artesunate (77% versus 38%; P < 0.001). Improved survival was associated with higher levels of protein-bound NO, decreased levels of CD4+ and CD8+ T cells in the brain, improved blood-brain barrier integrity, and improved coma scores, as well as higher levels of gamma interferon. GSNOR KO animals receiving WT bone marrow had significantly reduced survival following P. berghei ANKA infection compared to those receiving KO bone barrow (P < 0.001). Reciprocal transplants established that survival benefits of GSNOR deletion were attributable primarily to the T cell compartment. These data indicate a role for GSNOR in the host response to malaria infection and suggest that strategies to disrupt its activity will improve clinical outcomes by enhancing microvascular integrity and modulating T cell tissue tropism.


Assuntos
Álcool Desidrogenase/deficiência , Malária Cerebral/patologia , Plasmodium berghei/patogenicidade , Animais , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Artesunato , Modelos Animais de Doenças , Feminino , Malária Cerebral/tratamento farmacológico , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Análise de Sobrevida , Linfócitos T/imunologia , Resultado do Tratamento
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