RESUMEN
BACKGROUND: Heart failure is characterized by physical and emotional symptoms and decreased quality of life (QoL). Palliative care can reduce burdens of serious illness but often is limited to inpatient or academic settings. OBJECTIVES: To develop and test the Primary Education for Nurses in Palliative care-HF (PENPal-HF) intervention, training outpatient cardiology nurses to address symptom burden, patient priorities for care and QoL, and advance care planning as part of quarterly HF visits. METHODS: We conducted a pilot randomized clinical trial for adults with NYHA Stage III or IV HF and ≥ 2 hospitalizations in the past 12 months, recruited from a community-based cardiology clinic. Participants were randomized 2:1, PENPal-HF plus usual care versus usual care alone. Primary outcomes were feasibility and acceptability. RESULTS: We randomized 30 adults with Stage III HF - 20 to PENPal-HF and 10 to usual care. Most in the intervention group (71%) and in the control group (62%) completed the study through the final outcome assessment in week 56; 5 participants died. Of 20 participants in the intervention, 14 (70%) remained in the study through the end of intervention visits; 11 (55%) completed all visits. Most intervention participants (93.75%) agreed or strongly agreed that they were satisfied with their care, and 87.5% agreed or strongly agreed that all people with HF should receive the intervention. Most intervention group participants (93.75%) reported a perceived improvement in physical symptoms, mood, and/or QoL. CONCLUSIONS: This pilot study suggests that nurse-led primary palliative care in outpatient cardiology settings is promising. Research is warranted to determine efficacy and effectiveness.
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Cardiología , Insuficiencia Cardíaca , Adulto , Humanos , Cuidados Paliativos , Proyectos Piloto , Calidad de Vida , Insuficiencia Cardíaca/psicologíaRESUMEN
Stress-induced p38 mitogen-activated protein kinase (MAPK) activity is implicated in pathological remodeling in the heart. For example, constitutive p38 MAPK activation in cardiomyocytes induces pathological features, including myocyte hypertrophy, apoptosis, contractile dysfunction, and fetal gene expression. However, the physiological function of cardiomyocyte p38 MAPK activity in beneficial compensatory vascular remodeling is unclear. This report investigated the functional role and the underlying mechanisms of cardiomyocyte p38 MAPK activity in cardiac remodeling induced by chronic stress. Using both in vitro and in vivo model systems, we found that p38 MAPK activity is required for hypoxia-induced pro-angiogenic activity from cardiomyocytes and that p38 MAPK activation in cardiomyocyte is sufficient to promote paracrine signaling-mediated, pro-angiogenic activity. We further demonstrate that VEGF is a paracrine factor responsible for the p38 MAPK-mediated pro-angiogenic activity from cardiomyocytes and that p38 MAPK pathway activation is sufficient for inducing VEGF secretion from cardiomyocytes in an Sp1-dependent manner. More significantly, cardiomyocyte-specific inactivation of p38α in mouse heart impaired compensatory angiogenesis after pressure overload and promoted early onset of heart failure. In summary, p38αMAPK has a critical role in the cross-talk between cardiomyocytes and vasculature by regulating stress-induced VEGF expression and secretion in cardiomyocytes. We conclude that as part of a stress-induced signaling pathway, p38 MAPK activity significantly contributes to both pathological and compensatory remodeling in the heart.
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Endotelio Vascular/metabolismo , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Isquemia Miocárdica/metabolismo , Revascularización Miocárdica , Miocitos Cardíacos/metabolismo , Animales , Animales Recién Nacidos , Hipoxia de la Célula , Células Cultivadas , Cruzamientos Genéticos , Endotelio Vascular/citología , Endotelio Vascular/patología , Activación Enzimática , Regulación de la Expresión Génica , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Masculino , Ratones Noqueados , Ratones Transgénicos , Proteína Quinasa 14 Activada por Mitógenos/química , Proteína Quinasa 14 Activada por Mitógenos/genética , Isquemia Miocárdica/patología , Miocitos Cardíacos/citología , Miocitos Cardíacos/patología , Interferencia de ARN , Ratas Sprague-Dawley , Proteínas Recombinantes/metabolismo , Factor de Transcripción Sp1/antagonistas & inhibidores , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp1/metabolismo , Sus scrofa , Factor A de Crecimiento Endotelial Vascular/agonistas , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/agonistas , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Kinase homology domain (KHD) phosphorylation is required for activation of guanylyl cyclase (GC)-A and -B. Phosphopeptide mapping identified multiple phosphorylation sites in GC-A and GC-B, but these approaches have difficulty identifying sites in poorly detected peptides. Here, a functional screen was conducted to identify novel sites. Conserved serines or threonines in the KHDs of phosphorylated receptor GCs were mutated to alanine and tested for reduced hormone to detergent activity ratios. Mutation of Ser-489 in GC-B to alanine but not glutamate reduced the activity ratio to 60% of wild type (WT) levels. Similar results were observed with Ser-473, the homologous site in GC-A. Receptors containing glutamates for previously identified phosphorylation sites (GC-A-6E and GC-B-6E) were activated to ~20% of WT levels but the additional glutamate substitution for S473 or S489 increased activity to near WT levels. Substrate-velocity assays indicated that GC-B-WT-S489E and GC-B-6E-S489E had lower Km values and that WT-GC-B-S489A, GC-B-6E and GC-B-6E-S489A had higher Km values than WT-GC-B. Homologous desensitization was enhanced when GC-A contained the S473E substitution, and GC-B-6E-S489E was resistant to inhibition by a calcium elevating treatment or protein kinase C activation--processes that dephosphorylate GC-B. Mass spectrometric detection of a synthetic phospho-Ser-473 containing peptide was 200-1300-fold less sensitive than other phosphorylated peptides and neither mass spectrometric nor (32)PO(4) co-migration studies detected phospho-Ser-473 or phospho-Ser-489 in cells. We conclude that Ser-473 and Ser-489 are Km-regulating phosphorylation sites that are difficult to detect using current methods.
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Receptores del Factor Natriurético Atrial/metabolismo , Sustitución de Aminoácidos , Animales , Línea Celular , Humanos , Mutación Missense , Mapeo Peptídico/métodos , Péptidos/genética , Péptidos/metabolismo , Fosforilación/fisiología , Estructura Terciaria de Proteína/fisiología , Ratas , Receptores del Factor Natriurético Atrial/genéticaRESUMEN
The p38 mitogen-activated protein kinases (p38s) are stress-activated Ser/Thr kinases. Their activation has been associated with various pathological stressors in the heart. Activated p38 is implicated in a wide spectrum of cardiac pathologies, including hypertrophy, myocardial infarction, as well as systolic and diastolic heart failure. In this review, the specific contribution of different isoforms of p38 kinases to cardiac diseases as well as TAB-1-mediated non-canonical activation pathway are discussed as a rationale for inhibiting p38 activity to treat cardiac hypertrophy, ischemic injury, and heart failure. Finally, a summary of current clinical trials targeting p38 kinases in cardiovascular diseases is provided to highlight the potential promise as well as existing challenges of this therapeutic approach. This article is part of a special issue entitled "Key Signaling Molecules in Hypertrophy and Heart Failure."
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Cardiomegalia/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Terapia Molecular Dirigida , Infarto del Miocardio/tratamiento farmacológico , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatología , Corazón/efectos de los fármacos , Corazón/fisiopatología , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Humanos , Isoenzimas/metabolismo , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Miocardio/enzimología , Inhibidores de Proteínas Quinasas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidoresRESUMEN
Among the myriad of intracellular signaling networks that govern the cardiac development and pathogenesis, mitogen-activated protein kinases (MAPKs) are prominent players that have been the focus of extensive investigations in the past decades. The four best characterized MAPK subfamilies, ERK1/2, JNK, p38, and ERK5, are the targets of pharmacological and genetic manipulations to uncover their roles in cardiac development, function, and diseases. However, information reported in the literature from these efforts has not yet resulted in a clear view about the roles of specific MAPK pathways in heart. Rather, controversies from contradictive results have led to a perception that MAPKs are ambiguous characters in heart with both protective and detrimental effects. The primary object of this review is to provide a comprehensive overview of the current progress, in an effort to highlight the areas where consensus is established verses the ones where controversy remains. MAPKs in cardiac development, cardiac hypertrophy, ischemia/reperfusion injury, and pathological remodeling are the main focuses of this review as these represent the most critical issues for evaluating MAPKs as viable targets of therapeutic development. The studies presented in this review will help to reveal the major challenges in the field and the limitations of current approaches and point to a critical need in future studies to gain better understanding of the fundamental mechanisms of MAPK function and regulation in the heart.
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Corazón/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Miocardio/metabolismo , Animales , HumanosRESUMEN
In cardiac myocytes, excitation-contraction coupling depends upon sarcoplasmic reticular Ca2+ release triggered by Ca2+ influx through L-type Ca2+ channels. Although Na+-Ca2+ exchange (NCX) is essential for Ca2+ extrusion, its participation in the trigger process of excitation-contraction coupling is controversial. To investigate the role of NCX in triggering, we examined Ca2+ sparks in ventricular cardiomyocytes isolated from wild-type (WT) and cardiac-specific NCX knockout (KO) mice. Myocytes from young NCX KO mice are known to exhibit normal resting cytosolic Ca2+ and normal Ca2+ transients despite reduced L-type Ca2+ current. We loaded myocytes with fluo-3 to image Ca2+ sparks using confocal microscopy in line-scan mode. The frequency of spontaneous Ca2+ sparks was reduced in KO myocytes compared with WT. However, spark amplitude and width were increased in KO mice. Permeabilizing the myocytes with saponin eliminated differences between spontaneous sparks in WT and KO mice. These results suggest that sarcolemmal processes are responsible for the reduced spark frequency and increased spark width and amplitude in KO mice. When myocytes were loaded with 1 mM fluo-3 and 3 mM EGTA via the patch pipette to buffer diadic cleft Ca2+, the number of sparks triggered by action potentials was reduced by 60% in KO cells compared to WT cells, despite similar SR Ca2+ content in both cell types. When EGTA was omitted from the pipette solution, the number of sparks triggered in KO and WT myocytes was similar. Although the number of sparks was restored in KO cells, Ca2+ release was asynchronous. These results suggest that high subsarcolemmal Ca2+ is required to ensure synchronous triggering with short spark latency in the absence of NCX. In WT mice, high subsarcolemmal Ca2+ is not required for synchronous triggering, because NCX is capable of priming the diadic cleft with sufficient Ca2+ for normal triggering, even when subsarcolemmal Ca(2+) is lowered by EGTA. Thus, reducing subsarcolemmal Ca2+ with EGTA in NCX KO mice reveals the dependence of Ca2+ release on NCX.