RESUMO
Prostate-specific membrane antigen (PSMA) is a membrane-bound glutamate carboxypeptidase expressed in a number of tissues. PSMA participates in various biological functions depending on the substrate available in the particular tissue; in the brain, PSMA cleaves the abundant neuropeptide N-acetyl-aspartyl-glutamate to regulate release of key neurotransmitters, while intestinal PSMA cleaves polyglutamated peptides to supply dietary folate. PSMA expression is also progressively upregulated in prostate cancer where it correlates with tumor progression as well as in tumor vasculature, where it regulates angiogenesis. The previous research determined that PSMA cleavage of small peptides generated via matrix metalloprotease-mediated proteolysis of the extracellular matrix protein laminin potently activated endothelial cells, integrin signaling and angiogenesis, although the specific peptide substrates were not identified. Herein, using enzymatic analyses and LC/MS, we unequivocally demonstrate that several laminin-derived peptides containing carboxy-terminal glutamate moieties (LQE, IEE, LNE) are bona fide substrates for PSMA. Subsequently, the peptide products were tested for their effects on angiogenesis in various models. We report that LQ, the dipeptide product of PSMA cleavage of LQE, efficiently activates endothelial cells in vitro and enhances angiogenesis in vivo. Importantly, LQE is not cleaved by an inactive PSMA enzyme containing an active site mutation (E424S). Endothelial cell activation by LQ was dependent on integrin beta-1-induced activation of focal adhesion kinase. These results characterize a novel PSMA substrate, provide a functional rationale for the upregulation of PSMA in cancer cells and tumor vasculature and suggest that inhibition of PSMA could lead to the development of new angiogenic therapies.
Assuntos
Proteínas Angiogênicas/metabolismo , Antígenos de Superfície/metabolismo , Glutamato Carboxipeptidase II/metabolismo , Laminina/metabolismo , Antígenos de Superfície/genética , Adesão Celular , Dipeptídeos/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Glutamato Carboxipeptidase II/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrólise , Integrina beta1/metabolismo , Masculino , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Neovascularização Fisiológica , Fragmentos de Peptídeos/metabolismo , Proteólise , Especificidade por SubstratoRESUMO
Pulmonary arterial hypertension (PAH) is a fatal vasculopathy that ultimately leads to elevated pulmonary pressure and death by right ventricular (RV) failure, which occurs in part due to decreased fatty acid oxidation and cytotoxic lipid accumulation. In this study, we tested the hypothesis that decreased fatty acid oxidation and increased lipid accumulation in the failing RV is driven, in part, by a relative carnitine deficiency. We then tested whether supplementation of l-carnitine can reverse lipotoxic RV failure through augmentation of fatty acid oxidation. In vivo in transgenic mice harboring a human BMPR2 mutation, l-carnitine supplementation reversed RV failure by increasing RV cardiac output, improving RV ejection fraction, and decreasing RV lipid accumulation through increased PPARγ expression and augmented fatty acid oxidation of long chain fatty acids. These findings were confirmed in a second model of pulmonary artery banding-induced RV dysfunction. In vitro, l-carnitine supplementation selectively increased fatty acid oxidation in mitochondria and decreased lipid accumulation through a Cpt1-dependent pathway. l-Carnitine supplementation improves right ventricular contractility in the stressed RV through augmentation of fatty acid oxidation and decreases lipid accumulation. Correction of carnitine deficiency through l-carnitine supplementation in PAH may reverse RV failure.
RESUMO
Heart failure with preserved ejection fraction (HFpEF) currently has no therapies that improve mortality. Right ventricular dysfunction and pulmonary hypertension are common in HFpEF, and thought to be driven by obesity and metabolic syndrome. Thus, we hypothesized that an animal model of obesity-induced HFpEF with pulmonary hypertension would provide insight into the pathogenesis of right ventricular failure in HFpEF. Two strains of mice, one susceptible (AKR) and one resistant (C3H) to obesity-induced HFpEF, were fed high fat (60% fat) or control diet for 0, 2, or 20 weeks and evaluated by cardiac catheterization and echocardiography for development of right ventricular dysfunction, pulmonary hypertension, and HFpEF. AKR, but not C3H, mice developed right ventricular dysfunction, pulmonary hypertension, and HFpEF. NPRC, which antagonizes beneficial natriuretic peptide signaling, was found in RNA sequencing to be the most differentially upregulated gene in the right ventricle, but not left ventricle or lung, of AKR mice that developed pulmonary hypertension and HFpEF. Overexpression of NPRC in H9C2 cells increased basal cell size and increased expression of hypertrophic genes, MYH7 and NPPA. In conclusion, we have shown that NPRC contributes to right ventricular modeling in obesity-induced pulmonary hypertension-HFpEF by increasing cardiomyocyte hypertrophy. NPRC may represent a promising therapeutic target for right ventricular dysfunction in pulmonary hypertension-HFpEF.
RESUMO
Resumen ANTECEDENTES: La hemorragia puerperal tardía implica una importante morbilidad y mortalidad que requiere una actuación urgente. Su causa es muy variada y requiere una cuidadosa valoración que permita detenerla, sin complicaciones. CASO CLÍNICO: Paciente de 42 años que a las cinco semanas posteriores a una cesárea acudió a Urgencias debido a un sangrado puerperal abundante. Enseguida de un legrado y exhaustiva revisión en el quirófano en la ecografía se identificó un área parauterina anecogénica sugerente de dilatación aneurismática comunicada con la cavidad uterina. El diagnóstico se estableció con base en la angiografía y se confirmó luego de la embolización mediante radiología intervencionista, sin contratiempos, y resolución del cuadro. La paciente se dio de alta del hospital en los siguientes dos días, con posteriores revisiones que se reportaron normales. CONCLUSIONES: La patología vascular debe formar parte del diagnóstico diferencial del sangrado puerperal tardío y, si se diagnostica adecuadamente, puede facilitar el procedimiento terapéutico mediante radiología intervencionista y evitar, así, otros tratamientos más invasivos.
Abstract BACKGROUND: Late puerperal hemorrhage is a major morbidity and mortality that requires urgent action. Its cause is very varied and requires careful assessment to stop it without complications. CLINICAL CASE: A 42-year-old woman came to the emergency department five weeks after cesarean section for heavy puerperal bleeding. After curettage and thorough examination in the operating room, ultrasound identified an anechogenic parauterine area suggestive of aneurysmal dilatation in communication with the uterine cavity. The diagnosis was established based on angiography and confirmed after embolization by interventional radiology, without mishap, and resolution of the picture. The patient was discharged in two days, with subsequent revisions reported as normal. CONCLUSIONS: Vascular pathology should be part of the differential diagnosis of late puerperal hemorrhage and, if properly diagnosed, may facilitate the therapeutic procedure by interventional radiology and thus avoid other more invasive treatments.
RESUMO
Objetivo: Analizar la información obtenida de estudios previos acerca del cuadro clínico presente en enfermedad por SARS -CoV-2, así como los factores de riesgo y vulnerabilidad que predisponen a dicha enfermedad, para determinar los más frecuentes en interés de guiar al buen diagnóstico y tratamiento de la misma. Método: Revisión sistemática utilizando la internet y motores de búsqueda como Google Scholar y PubMed. Las fuentes revisadas se encuentran publicadas en revistas en línea tales como Elsevier, Jama, SciELO, Science Direct, entre otras. Se incluyeron documentos por la Secretaría de Salud de México, y la Organización Mundial de la Salud. Resultados: Se observó que la sintomatología del SARS-CoV-2 es variable, encontraron casos asintomáticos. Existe una alta incidencia en distintos síntomas como son: fiebre, tos seca y cansancio. La COVID-19 tiene una letalidad de 10.2% en México. Entre las complicaciones más comunes se encontraron neumonía, insuficiencia cardiaca. Se observaron varios factores de riesgo que pueden llevar a una muerte como desenlace, tales como: HTA, obesidad, ECV, EPOC, cáncer y diabetes. Existen factores de vulnerabilidad como: inadecuado acceso de agua limpia y saneamiento, infraestructura inadecuada, inseguridad alimentaria, entre otros. Conclusiones: El conocimiento de los síntomas más comunes en la enfermedad por SARS-CoV-2 es una herramienta de utilidad clínica para mejorar la atención médica. La presencia de comorbilidades dispone a un agravamiento significativo de la enfermedad, los factores de riesgo y vulnerabilidad apuntan a la necesidad de optimización de actividades en materia de salud pública.(AU)
Objective: To analyze the information obtained from previous studies about the clinical picture present in SARS -CoV-2 disease, as well as the risk and vulnerability factors that predispose to this disease, in order to determine the most frequent ones in the interest of guiding the good diagnosis and treatment of the disease. Method: The reviewed sources are published in online journals such as Elsevier, Jama, SciELO, Science Direct, among others. Also included were documents published by the Mexican Ministry of Health, and the World Health Organization. Results: It was observed that the symptomatology of SARS-CoV-2 is variable, asymptomatic cases were found. There is a high incidence of different symptoms such as: fever, dry cough, tiredness. COVID-19 has a 10.2% lethality in Mexico. Among the most common complications were found, pneumonia, heart failure. Several risk factors were observed that can lead to death as an outcome, such as: ATH, obesity, CVD, COPD, cancer and diabetes. In addition to these risk factors there are vulnerability factors such as: inadequate access to clean water and sanitation, inadequate infrastructure, food insecurity, among other. Conclusions: The knowledge of the most common symptoms of SARS-CoV-2 disease is a clinically useful tool for improving health care. On the other hand, the presence of comorbidities leads to a significant worsening of the disease, risk and vulnerability factors point to the need for optimization of public health activities.(AU)
Assuntos
Humanos , Masculino , Feminino , Fatores de Risco , Infecções por Coronavirus/epidemiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Infecções por Coronavirus/complicações , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/fisiopatologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Pandemias , México , Vulnerabilidade em Saúde , Pacientes InternadosRESUMO
In this paper, the chemical composition, the main physicochemical properties, phase behavior and thermal stability of rambutan (Nephelium lappaceum L.) seed fat were studied. These results showed that the almond-like decorticated seed represents 6.1% of the wet weight fruit and is: 1.22% ash, 7.80% protein, 11.6% crude fiber, 46% carbohydrates, and 33.4% fat (d.b.). The main fatty acids in the drupe fat were 40.3% oleic, 34.5% arachidic, 6.1% palmitic, 7.1% stearic, 6.3% gondoic, and 2.9% behenic; the refraction, saponification and iodine values were 1.468, 186, and 47.0, respectively. The phase behavior analysis showed relatively simple crystallization and melting profiles: crystallization showed three well-differentiated groups of triglycerides around maximum peaks at +30.8, +15.6 and -18.1 degrees C; the fat-melting curve had a range between -14.5 and +51.8 degrees C with a fusion enthalpy of 124.3 J/g. The thermal stability analyzed in an inert atmosphere of N(2) and in a normal oxidizing atmosphere, showed that in the latter, fat decomposition begins at 237.3 degrees C and concludes at 529 degrees C, with three stages of decomposition. According to these results, rambutan seed fat has physicochemical and thermal characteristics that may become interesting for specific applications in several segments of the food industry.