Browsing by Author "Moya, J."

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    Angiotensin-(1-9) prevents vascular remodeling by decreasing vascular smooth muscle cell dedifferentiation through a FoxO1-dependent mechanism
    (2020) Norambuena Soto, I.; Ocaranza Jeraldino, M. Paz; Cancino Arenas, N.; Sanhueza Olivares, F.; Villar Fincheira, P.; Leiva Navarrete, S.; Mancilla Medina, C.; Moya, J.; Jalil Milad, Jorge; Castro Gálvez, Pablo Federico; Novoa, Ulises; Lavandero, S.; Chiong, M.; Norambuena Soto, I.; Ocaranza, María Paz; Cancino Arenas, N.; Sanhueza Olivares, F.; Villar Fincheira, P.; Leiva Navarrete, S.; Mancilla Medina, C.; Moya, J.; Jalil Milad, Jorge; Castro Gálvez, Pablo Federico; Novoa, Ulises; Lavandero, S.; Chiong, M.
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    Angiotensin-(1-9) reverses experimental hypertension and cardiovascular damage by inhibition of the angiotensin converting enzyme/Ang II axis
    (2014) Ocaranza, María Paz; Moya, J.; Morales, C.; Pinto, M.; Escudero, N.; Novoa, Ulises; Godoy, I.; Jalil Milad, Jorge
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    Angiotensina-(1-9) disminuye el remodelamiento cardiovascular hipertensivo independiente de los niveles de ECA y de angiotensina II
    (2012) Moya, J.; Novoa, Ulises; Godoy, I.; Chiong, M.; Lavandero, S.; Jalil Milad, Jorge; Ocaranza Jeraldino, M. Paz; Moya, J.; Novoa, Ulises; Godoy, I.; Chiong, M.; Lavandero, S.; Jalil Milad, Jorge; Ocaranza, María Paz
    Resumen: La enzima convertidora de angiotensina I (ECA2) a través de Angiotensina (Ang)-(1-9) más que Ang-(1-7) contrarresta los efectos deletéreos de ECA y Ang II. Se desconoce si Ang-(1-9) es efectiva en el tratamiento del remodelamiento cardiovascular (RMCV) hipertensivo, en ratas con polimorfismo del gen de la ECA. Objetivo: Determinar el efecto de Ang-(1-9) en el tratamiento del RMCV hipertensivo en ratas con niveles genéticamente determinados de ECA y Ang II. Métodos: Ratas normotensas homocigotas, Lewis (LL) y Brown Norway (BN), se les indujo HTA a través del modelo Goldblatt (GB, 2 riñones-1 pinzado). Después de 4 semanas, las ratas hipertensas se rando-mizaron para recibir Ang-(1-9) (602 ng/Kg min) o una coadministración de Ang-(1-9)+A779 (100 ng/Kg min, antagonista del receptor MAS de Ang-(1-7)) durante 14 días mediante una minibomba. Como controles se usaron ratas sometidas a operación ficticia (Sham). Se determinó masa corporal (MC), presión arterial sistólica (PAS), masa ventricular (MV), área de cardiomiocitos (AC), área y grosor de la túnica media (ATM, GTM), fracción volumétrica de colágeno total (FVCT) en el ventrículo izquierdo (VI), niveles proteicos de colágeno tipo I (Col I) en la aorta (Ao) y la infiltración de macrófagos en Ao y VI, por medio de su molécula especifica ED1 (ED1-Ao, ED1-VI). Resultados: La administración de Ang-(1-9) disminuyó significativamente PAS, MV, AC, FVCT, Col I, ATM, GTM, ED1-Ao (-) y ED1-VI, en las ratas hipertensas LL y BN respecto a las ratas GB sin tratamiento, respectivamente. Este efecto no fue inhibido por el antagonista A779. El polimorfismo de la ECA no modificó la respuesta al tratamiento. Conclusión: Ang-(1-9) redujo eficazmente la HTA y el RMCV secundario, independiente al polimorfismo en el gen de la ECA. Este efecto posiblemente es directo ya que no fue mediado por Ang-(1-7). Fondecyt 1100874.
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    El efecto anti-hipertensivo de Angiotensina-(1-9) es mediado por aumento temprano de la diuresis y natriuresis
    (2015) Moya, J.; Novoa, Ulises; Escudero, N.; Barrientos, V.; Chiong, M.; Lavandero, S.; Michea, L.; Jalil Milad, Jorge; Oca. P.
    Introducción: Angiotensina (Ang)-(1-9) posee propiedades anti-hipertensivas y efecto protector a nivel cardiovascular en ratas hipertensas. Sin embargo, se desconoce si estos efectos están asociados a un mecanismo de desbalance de sodio a nivel renal. Objetivo: Determinar si el efecto anti-hipertensivo de Ang-(1-9) está asociado a un mecanismo diurético-na-triurético. Método: Ratas macho Sprague Dawley (200 ± 10g) fueron aleatorizadas para recibir Ang II (400 ng/kgmin) vía bomba osmótica. Como control se utilizaron ratas con operación sham (n=18). Después de 2 semanas desde la instalación de bomba, las ratas Sham e hipertensas fueron randomizadas para recibir vehículo (n=10), Ang-(1-9) (602 ng/kg/min, n=17) o una co-administración de Ang-(1-9) y A779 (100 ng kg-1min-1, n=7 bloqueador del receptor MAS) por 2 semanas. Resultados: Se determinó la presión arterial sistólica (PAS), masa ventricular relativa (MVR), área y perímetro de los cardiomiocitos (AC y PC) y la fracción volumétrica de colágeno total (FVCT). Para evaluar la diuresis y natriuresis se utilizaron ratas normotensas que fueron randomizadas para recibir vehículo (n=8) o Ang-(1-9) (600 ngKg-1min-1, n=8) por 6 días. Se observó un incremento significativo(p<0.05) de PAS (33%), MVR (17%), AC (64%), PC (20%), FVCT (46%). La administración crónica de Ang-(1-9) disminuyó PAS (20%), MVR (13 %), AC (35%), PC (20%) y FVCT (20%). Estos efectos no fueron mediados por el receptor MAS. Al comparar las ratas normotensas tratadas con vehículo o Ang-(1-9), se observó un aumento significativo de la diuresis y natriuresis en los días 2 y 3 en los animales con infusión de Ang-(1-9). Conclusión: Ang-(1-9) reduce la hipertensión y el remodelamiento cardíaco en ratas hipertensas. En animales normotensos se demostró que el tratamiento con Ang-(1-9)-induce diuresis y natriuresis. Este es el primer reporte que señala que el efecto de Ang-(1-9) está asociado a una regulación del sodio a nivel renal.
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    Mayores niveles de ECA y Angiotensina II determinados genéticamente, se asocian a menor actividad del eje ECA2/angiotensina-(1-9) y mayor remodelamiento de la pared aórtica de ratas hipertensas
    (2012) Moya, J.; Novoa, Ulises; Escudero, N.; Godoy, I.; Chiong, M.; Lavandero, S.; Jalil Milad, Jorge; Ocaranza Jeraldino, M. Paz; Moya, J.; Novoa, Ulises; Escudero, N.; Godoy, I.; Chiong, M.; Lavandero, S.; Jalil Milad, Jorge; Ocaranza, María Paz
    Introducción: El polimorfismo del gen de la enzima convertidora de angiotensina I (ECA) determina mayor actividad de la ECA y mayores niveles de angioten-sina (Ang) II. Un polimorfismo similar ha sido descrito en humanos. La ECA2, a través de Ang-(1-9) más que Ang-(1-7), contrarresta los efectos deletéreos de Ang II. Se desconoce si el polimorfismo de la ECA frente a un estímulo hipertensivo modifica el eje ECA2/Ang-(1-9) y determina mayor remodelamiento de la pared aórtica de ratas hipertensas. Objetivo: Determinar el efecto del polimorfismo del gen de la ECA en la actividad del eje ECA2/Ang-(1-9) y su efecto en el remodelamiento de la pared aórtica secundaria a la hipertensión arterial (HTA) experimental. Métodos: Se usaron ratas macho homocigotas de 150 gr BN y LL. Se indujo HTA por el procedimiento Goldblatt (GB, 2 K-1clip). Ratas pseudo-operadas se usaron como controles (Sham). A las 6 semanas post cirugía se determinaron en la aorta las actividades de ECA y ECA2, los niveles de Ang II/Ang-(1-9), colágeno tipo I, células positivas para el marcador de inflamación ED-1, área y grosor de la túnica media (ATM, GTM). Resultados: El polimorfismo de la ECA con mayores niveles de ECA y Ang II determinó una mayor disminución de la actividad de ECA2, menores niveles de Ang-(1-9) y mayor remodelamiento de la pared aórtica tanto en animales normotensos como hipertensos. Conclusión: El polimorfismo de la ECA con mayor actividad de ECA y AngII determina una interregu-lación de los ejes ECA/AngII y ECA2/Ang-(1-9) lo que se asocia a mayor remodelamiento de la pared aórtica. Fondecyt 1100874.
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    Mechanisms of favorable effects of Rho kinase inhibition on myocardial remodeling and systolic function after experimental myocardial infarction in the rat
    (2016) Mera, C.; Godoy, I.; Ramírez, R.; Moya, J.; Ocaranza, María Paz; Jalil Milad, Jorge
    Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.Objective: The objective of this study was to determine the molecular mechanisms by which cardiac Rho-associated coiled-coil containing protein kinase (ROCK) activation after myocardial infarction (MI) does intervene in cardiac systolic function decline and remodeling. Methods: Simultaneous measurement of different cardiac ROCK target proteins levels, in vivo left ventricular (LV) systolic function, myocardial fibrosis and hypertrophy in rats with MI under ROCK inhibition with fasudil. Results: Seven days after MI, the ventricular mass increased significantly by 5.6% in the MI group and was reduced with fasudil. LV systolic dysfunction improved significantly with fasudil whereas cardiac ROCK activation was reduced to sham levels. The ROCK inhibitor also reduced increased cardiac levels of both ROCK1 and ROCK2 isoforms, cardiomyocyte ROCK2 fluorescence levels and β-myosin heavy chain (MHC) levels in addition to myocardial collagen volume fraction decline. Compared with sham rats, troponin phosphorylation levels after MI were similar and ROCK inhibition reduced them. MI significantly increased phosphorylation levels of extracellular-signal-regulated kinase (ERK) 42 and ERK 44 by twofold and 63%, respectively, whereas in the fasudil-treated MI group these levels were similar to those in the sham group. MI significantly increased phosphorylated levels of the transcription factor GATA-4 and the ROCK inhibitor normalized them. Conclusions: LV systolic dysfunction after MI was strongly associated with cardiac ROCK activation and subsequent phosphorylation of ROCK target proteins that promote ventricular remodeling such as β-MHC and the ERK/GATA-4 pathway. ROCK inhibition with fasudil significantly improved systolic function, diminished myocardial fibrosis and normalized β-MHC and ERK/GATA-4 phosphorylation levels.
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    Menores niveles tisulares de la enzima convertidora de angiotensina I homologa (ECA-2) y angiotensina-(1-9) están asociados a mayor remodelamiento de la pared aórtica de ratas hipertensas
    (2010) Ocaranza, María Paz; Moya, J.; Pinto, M.; Escudero, N.; Valenzuela, F.; Varas, M.; Godoy, I.; Chiong, M.; Lavandero, S.; Jalil Milad, Jorge
    Antecedentes: Recientemente hemos propuesto en un modelo experimental de infarto al miocardio una significativa interregulación entre los niveles de la enzima convertidora de angiotensina I (ECA) y su homologa (ECA-2), junto con que angiotensina (Ang)-(1-9) más que Ang-(1-7) actuaría como un contrarregulador de Ang II. Sin embargo tal relación no se ha investigado en el remodelado aórtico hipertensivo. Objetivo: Determinar la expresion de ECA y ECA-2, los niveles de Angs I, II, (1-7) y (1-9) y los parámetros de remodelado de la pared aórtica de ratas hipertensas. Métodos: Ratas normotensas Lewis (n=18) fueron randomizadas a hipertension (HTA) por sobrecarga de presion (modelo Goldblatt, GB, 2 riñones-1 pinzado, n=9). Ratas pseudo-operadas se usaron como controles (S, n=9). A las 6 semanas post cirugía, se determinó la masa cardíaca relativa (MCR) y la presion arterial sistólica (PAS). En la aorta torácica se determinó el grosor de la túnica media (GTM), área de la TM (ATM), niveles de mRNA de ECA y ECA-2, factor de crecimiento transformante tipo ß (TGF-ß), inhibidor del activador de plasminógeno (PAI-1) y de la proteína quimioatractante de monocitos (MCP-1) por RT-PCR. La actividad y niveles proteicos de ECA y ECA-2 por fluorimetría y Western blot y los niveles de Angs I, II, (1-7) y (1-9) por HPLC y radioinmunoensayo. Resultados: La MCR y la PAS aumentaron significativamente (p<0,05) en el grupo GB respecto a su control S. Las ratas hipertensas mostraron un aumento significativo (p<0.05) del GTM (18%), ATM (31%), niveles de mRNA de ECA (164%,), TGF-/3 (105%,), PAI-1(51%>), MCP-1 (53%,) junto con mayor actividad (89%,), niveles proteicos de ECA (130%,) y Ang II (48%,). Esos efectos se asociaron a una significativa disminución del mRNA, los niveles proteicos y actividad de ECA-2 (- 55%, -41%, y 54%, respectivamente) y a menores niveles aórticos (-25%,) de Ang- (1-9), sin diferencias en los niveles de ang-(1-7). Conclusion: Estos resultados fuertemente sugieren que en la hipertension arterial experimental, el remodelado de la pared aórtica está asociado a una interacción entre ECA y ECA-2 y los niveles de Ang II y Ang-(1-9), pero no de Ang-(1-7). Antecedentes: Recientemente hemos propuesto en un modelo experimental de infarto al miocardio una significativa interregulación entre los niveles de la enzima convertidora de angiotensina I (ECA) y su homologa (ECA-2), junto con que angiotensina (Ang)-(1-9) más que Ang-(1-7) actuaría como un contrarregulador de Ang II. Sin embargo tal relación no se ha investigado en el remodelado aórtico hipertensivo. Objetivo: Determinar la expresion de ECA y ECA-2, los niveles de Angs I, II, (1-7) y (1-9) y los parámetros de remodelado de la pared aórtica de ratas hipertensas. Métodos: Ratas normotensas Lewis (n=18) fueron randomizadas a hipertension (HTA) por sobrecarga de presion (modelo Goldblatt, GB, 2 riñones-1 pinzado, n=9). Ratas pseudo-operadas se usaron como controles (S, n=9). A las 6 semanas post cirugía, se determinó la masa cardíaca relativa (MCR) y la presion arterial sistólica (PAS). En la aorta torácica se determinó el grosor de la túnica media (GTM), área de la TM (ATM), niveles de mRNA de ECA y ECA-2, factor de crecimiento transformante tipo ß (TGF-ß), inhibidor del activador de plasminógeno (PAI-1) y de la proteína quimioatractante de monocitos (MCP-1) por RT-PCR. La actividad y niveles proteicos de ECA y ECA-2 por fluorimetría y Western blot y los niveles de Angs I, II, (1-7) y (1-9) por HPLC y radioinmunoensayo. Resultados: La MCR y la PAS aumentaron significativamente (p<0,05) en el grupo GB respecto a su control S. Las ratas hipertensas mostraron un aumento significativo (p<0.05) del GTM (18%), ATM (31%), niveles de mRNA de ECA (164%,), TGF-/3 (105%,), PAI-1(51%>), MCP-1 (53%,) junto con mayor actividad (89%,), niveles proteicos de ECA (130%,) y Ang II (48%,). Esos efectos se asociaron a una significativa disminución del mRNA, los niveles proteicos y actividad de ECA-2 (- 55%, -41%, y 54%, respectivamente) y a menores niveles aórticos (-25%,) de Ang- (1-9), sin diferencias en los niveles de ang-(1-7). Conclusion: Estos resultados fuertemente sugieren que en la hipertension arterial experimental, el remodelado de la pared aórtica está asociado a una interacción entre ECA y ECA-2 y los niveles de Ang II y Ang-(1-9), pero no de Ang-(1-7). Antecedentes: Recientemente hemos propuesto en un modelo experimental de infarto al miocardio una significativa interregulación entre los niveles de la enzima convertidora de angiotensina I (ECA) y su homologa (ECA-2), junto con que angiotensina (Ang)-(1-9) más que Ang-(1-7) actuaría como un contrarregulador de Ang II. Sin embargo tal relación no se ha investigado en el remodelado aórtico hipertensivo. Objetivo: Determinar la expresion de ECA y ECA-2, los niveles de Angs I, II, (1-7) y (1-9) y los parámetros de remodelado de la pared aórtica de ratas hipertensas. Métodos: Ratas normotensas Lewis (n=18) fueron randomizadas a hipertension (HTA) por sobrecarga de presion (modelo Goldblatt, GB, 2 riñones-1 pinzado, n=9). Ratas pseudo-operadas se usaron como controles (S, n=9). A las 6 semanas post cirugía, se determinó la masa cardíaca relativa (MCR) y la presion arterial sistólica (PAS). En la aorta torácica se determinó el grosor de la túnica media (GTM), área de la TM (ATM), niveles de mRNA de ECA y ECA-2, factor de crecimiento transformante tipo ß (TGF-ß), inhibidor del activador de plasminógeno (PAI-1) y de la proteína quimioatractante de monocitos (MCP-1) por RT-PCR. La actividad y niveles proteicos de ECA y ECA-2 por fluorimetría y Western blot y los niveles de Angs I, II, (1-7) y (1-9) por HPLC y radioinmunoensayo. Resultados: La MCR y la PAS aumentaron significativamente (p<0,05) en el grupo GB respecto a su control S. Las ratas hipertensas mostraron un aumento significativo (p<0.05) del GTM (18%), ATM (31%), niveles de mRNA de ECA (164%,), TGF-/3 (105%,), PAI-1(51%>), MCP-1 (53%,) junto con mayor actividad (89%,), niveles proteicos de ECA (130%,) y Ang II (48%,). Esos efectos se asociaron a una significativa disminución del mRNA, los niveles proteicos y actividad de ECA-2 (- 55%, -41%, y 54%, respectivamente) y a menores niveles aórticos (-25%,) de Ang- (1-9), sin diferencias en los niveles de ang-(1-7). Conclusion: Estos resultados fuertemente sugieren que en la hipertension arterial experimental, el remodelado de la pared aórtica está asociado a una interacción entre ECA y ECA-2 y los niveles de Ang II y Ang-(1-9), pero no de Ang-(1-7).
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    La sobreexpresión del gen de enzima convertidora de angiotensina homóloga (ECA2) revierte la hipertensión arterial y el remodelado cardíaco experimental
    (2010) Ramos, E.; Herrera, A.; Moya, J.; Apablaza, F.; Godoy, I.; Jalil Milad, Jorge; Lavandero, S.; Chiong, M.; Ocaranza, María Paz
    Antecedentes: La sobreexpresion génica de la enzima convertidora de angiotensina I homologa (ECA2) se asocia con prevención de la hipertrofia y fibrosis cardiaca dependiente de angiotensina (Ang) II. Sin embargo se desconoce si su sobreexpresion reduce la hipertensión arterial (HTA) y revierte el consecuente remodelado mio-cárdico (RM) dependiente de Ang II. Objetivo: Determinar si la sobreexpresion adenoviral (Ad) del gen de la ECA2 en el miocardio disminuye la HTA y RM experimental en ratas con niveles genéticamente determinados de ECA y Ang II. Métodos: Ratas homocigotas normotensas Lewis (LL) y Brown Borway (BN), con menores y mayores niveles circulantes de ECA y Ang II, respectivamente, se hicieron hipertensas por el procedimiento Goldblatt (GB). Como controles se usaron ratas seudo-operadas (sham). A la semana 5 post cirugía y con HTA establecida > 140 mmHg, las ratas se randomizaron a inyección intra-miocárdica con un AdECA2 o Ad proteína fluorescente verde (GFP) como controles de infección. A la semana post infección adenoviral, los ratas se sacrificaron y se determinaron peso corporal (PC, g), masa cardiaca (MC, mg), presión arterial sistólica (RAS, mmHg), área (AC, um2) y perímetro (PERC, um) de cardiomiocitos y contenido de colágeno (%) miocárdico (CM), sub-endocárdico (CS)ytotal(CT). Resultados: La HTA aumentó significativamente la MC, MCR, AC, PERC como también el CM, CS y CT en las ratas GB vs Sham, sin diferencias en el PC ni por efecto del polimorfismo de la ECA. La sobreexpresion de ECA2 disminuyó significativamente la RAS (15% y 27%), AC (25% y 25% ) y PERC (17 % y 18%) en las ratas LL y BN vs ratas hipertensas, respectivamente. Estos resultados se asociaron a una disminución significativa del CS (LL = 37%, BN = 39%), CM (LL = 54%) y CT (LL = 42%, BN = 22%) respecto a las ratas GB. Conclusión: En ratas con HTA establecida, la sobre-expresión miocárdica de ECA2 disminuyó la HTA y el desarrollo de hipertrofia y fibrosis cardíaca hipertensiva experimental en ratas con diferentes niveles de ECA y Ang II. FONDECYT 1070662.