RESUMO
BACKGROUND: Previous studies suggest a relationship of the epicardial adipose tissue (EAT) with progression and calcification of the atherosclerotic plaque; however, it is unknown if this tissue expresses genes that may participate on these processes and if the expression of these genes is regulated by high-density lipoprotein (HDL) subclasses. METHODS: To explore this possibility, we determined the mRNA expression by qPCR of a pro-calcifying gene (osteopontin (OPN)), and two anti-calcifying genes (osteoprotegerin (OPG) and osteonectin (ON)), in biopsies of EAT obtained from 15 patients with coronary artery disease (CAD) determined by angiography, and 15 patients with diagnostic of aortic valve stenosis but without CAD as control group. We determined the distribution and composition of HDL subclasses by electrophoresis and their statistical relationship with the gene expression in EAT. RESULTS: EAT from CAD patients showed a higher expression level of OPN and OPG than control group, whereas ON expression was similar between groups. Large HDL subclasses were cholesterol-poor in CAD patients as estimated by the cholesterol-to-phospholipid ratio. A linear regression model showed an independent association of OPN expression with HDL3a-cholesterol, and OPG expression with the relative proportion of HDL3b protein. Logistic analysis determined that OPN expression was positively associated with the presence of atherosclerotic plaque CONCLUSION: OPN, ON, and OPG genes are transcribed in EAT; to the exception of ON, the level of expression was different in CAD patients and control group, and correlated with some HDL subclasses, suggesting a new role of these lipoproteins.
Assuntos
Estenose da Valva Aórtica/genética , Doença da Artéria Coronariana/genética , Osteopontina/genética , Osteoprotegerina/genética , Placa Aterosclerótica/genética , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Idoso , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Estudos de Casos e Controles , HDL-Colesterol/sangue , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Lipoproteínas HDL3/genética , Lipoproteínas HDL3/metabolismo , Masculino , Pessoa de Meia-Idade , Osteonectina/genética , Osteonectina/metabolismo , Osteopontina/metabolismo , Osteoprotegerina/metabolismo , Pericárdio/metabolismo , Pericárdio/patologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Índice de Gravidade de DoençaRESUMO
En esta revisión se describen los diferentes sistemas de transporte para aminoácidos, la caracterización de éstos y de sus componentes, los factores que afectan las características cinéticas de los acarreadores específicos de los sistemas de transporte, y la importancia del transporte de aminoácidos en el mantenimiento de las concentraciones plasmáticas e intracelulares de aminoácidos en diversos tejidos, así como su papel en el control del metabolismo de aminoácidos.