RONALDO HONORATO BARROS DOS SANTOS

Índice h a partir de 2011
11
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico

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Agora exibindo 1 - 3 de 3
  • article 11 Citação(ões) na Scopus
    Impairment of Multiple Mitochondrial Energy Metabolism Pathways in the Heart of Chagas Disease Cardiomyopathy Patients
    (2021) TEIXEIRA, Priscila Camillo; DUCRET, Axel; LANGEN, Hanno; NOGOCEKE, Everson; SANTOS, Ronaldo Honorato Barros; NUNES, Joao Paulo Silva; BENVENUTI, Luiz; LEVY, Debora; BYDLOWSKI, Sergio Paulo; BOCCHI, Edimar Alcides; TAKARA, Andreia Kuramoto; FIORELLI, Alfredo Inacio; STOLF, Noedir Antonio; POMERANZEFF, Pablo; CHEVILLARD, Christophe; KALIL, Jorge; CUNHA-NETO, Edecio
    Chagas disease cardiomyopathy (CCC) is an inflammatory dilated cardiomyopathy occurring in 30% of the 6 million infected with the protozoan Trypanosoma cruzi in Latin America. Survival is significantly lower in CCC than ischemic (IC) and idiopathic dilated cardiomyopathy (DCM). Previous studies disclosed a selective decrease in mitochondrial ATP synthase alpha expression and creatine kinase activity in CCC myocardium as compared to IDC and IC, as well as decreased in vivo myocardial ATP production. Aiming to identify additional constraints in energy metabolism specific to CCC, we performed a proteomic study in myocardial tissue samples from CCC, IC and DCM obtained at transplantation, in comparison with control myocardial tissue samples from organ donors. Left ventricle free wall myocardial samples were subject to two-dimensional electrophoresis with fluorescent labeling (2D-DIGE) and protein identification by mass spectrometry. We found altered expression of proteins related to mitochondrial energy metabolism, cardiac remodeling, and oxidative stress in the 3 patient groups. Pathways analysis of proteins differentially expressed in CCC disclosed mitochondrial dysfunction, fatty acid metabolism and transmembrane potential of mitochondria. CCC patients' myocardium displayed reduced expression of 22 mitochondrial proteins belonging to energy metabolism pathways, as compared to 17 in DCM and 3 in IC. Significantly, 6 beta-oxidation enzymes were reduced in CCC, while only 2 of them were down-regulated in DCM and 1 in IC. We also observed that the cytokine IFN-gamma, previously described with increased levels in CCC, reduces mitochondrial membrane potential in cardiomyocytes. Results suggest a major reduction of mitochondrial energy metabolism and mitochondrial dysfunction in CCC myocardium which may be in part linked to IFN-gamma. This may partially explain the worse prognosis of CCC as compared to DCM or IC.
  • article 7 Citação(ões) na Scopus
    Matrix Metalloproteinase 2 and 9 Enzymatic Activities are Selectively Increased in the Myocardium of Chronic Chagas Disease Cardiomyopathy Patients: Role of TIMPs
    (2022) BARON, Monique Andrade; FERREIRA, Ludmila Rodrigues Pinto; TEIXEIRA, Priscila Camillo; MORETTI, Ana Iochabel Soares; SANTOS, Ronaldo Honorato Barros; FRADE, Amanda Farage; KURAMOTO, Andreia; DEBBAS, Victor; BENVENUTI, Luiz Alberto; GAIOTTO, Fabio Antonio; BACAL, Fernando; POMERANTZEFF, Pablo; CHEVILLARD, Christophe; KALIL, Jorge; CUNHA-NETO, Edecio
    Chronic Chagas disease (CCC) is an inflammatory dilated cardiomyopathy with a worse prognosis compared to other cardiomyopathies. We show the expression and activity of Matrix Metalloproteinases (MMP) and of their inhibitors TIMP (tissue inhibitor of metalloproteinases) in myocardial samples of end stage CCC, idiopathic dilated cardiomyopathy (DCM) patients, and from organ donors. Our results showed significantly increased mRNA expression of several MMPs, several TIMPs and EMMPRIN in CCC and DCM samples. MMP-2 and TIMP-2 protein levels were significantly elevated in both sample groups, while MMP-9 protein level was exclusively increased in CCC. MMPs 2 and 9 activities were also exclusively increased in CCC. Results suggest that the balance between proteins that inhibit the MMP-2 and 9 is shifted toward their activation. Inflammation-induced increases in MMP-2 and 9 activity and expression associated with imbalanced TIMP regulation could be related to a more extensive heart remodeling and poorer prognosis in CCC patients.
  • article 22 Citação(ões) na Scopus
    Co-Exposure of Cardiomyocytes to IFN-gamma and TNF-alpha Induces Mitochondrial Dysfunction and Nitro-Oxidative Stress: Implications for the Pathogenesis of Chronic Chagas Disease Cardiomyopathy
    (2021) NUNES, Joao Paulo Silva; ANDRIEUX, Pauline; BROCHET, Pauline; ALMEIDA, Rafael Ribeiro; KITANO, Eduardo; HONDA, Andre Kenji; IWAI, Leo Kei; ANDRADE-SILVA, Debora; GOUDENEGE, David; SILVA, Karla Deysiree Alcantara; VIEIRA, Raquel de Souza; LEVY, Debora; BYDLOWSKI, Sergio Paulo; GALLARDO, Frederic; TORRES, Magali; BOCCHI, Edimar Alcides; MANO, Miguel; SANTOS, Ronaldo Honorato Barros; BACAL, Fernando; POMERANTZEFF, Pablo; LAURINDO, Francisco Rafael Martins; TEIXEIRA, Priscila Camillo; NAKAYA, Helder I.; KALIL, Jorge; PROCACCIO, Vincent; CHEVILLARD, Christophe; CUNHA-NETO, Edecio
    Infection by the protozoan Trypanosoma cruzi causes Chagas disease cardiomyopathy (CCC) and can lead to arrhythmia, heart failure and death. Chagas disease affects 8 million people worldwide, and chronic production of the cytokines IFN-gamma and TNF-alpha by T cells together with mitochondrial dysfunction are important players for the poor prognosis of the disease. Mitochondria occupy 40% of the cardiomyocytes volume and produce 95% of cellular ATP that sustain the life-long cycles of heart contraction. As IFN-gamma and TNF-alpha have been described to affect mitochondrial function, we hypothesized that IFN-gamma and TNF-alpha are involved in the myocardial mitochondrial dysfunction observed in CCC patients. In this study, we quantified markers of mitochondrial dysfunction and nitro-oxidative stress in CCC heart tissue and in IFN-gamma/TNF-alpha-stimulated AC-16 human cardiomyocytes. We found that CCC myocardium displayed increased levels of nitro-oxidative stress and reduced mitochondrial DNA as compared with myocardial tissue from patients with dilated cardiomyopathy (DCM). IFN-gamma/TNF-alpha treatment of AC-16 cardiomyocytes induced increased nitro-oxidative stress and decreased the mitochondrial membrane potential (Delta psi m). We found that the STAT1/NF-kappa B/NOS2 axis is involved in the IFN-gamma/TNF-alpha-induced decrease of Delta psi m in AC-16 cardiomyocytes. Furthermore, treatment with mitochondria-sparing agonists of AMPK, NRF2 and SIRT1 rescues Delta psi m in IFN-gamma/TNF-alpha-stimulated cells. Proteomic and gene expression analyses revealed that IFN-gamma/TNF-alpha-treated cells corroborate mitochondrial dysfunction, transmembrane potential of mitochondria, altered fatty acid metabolism and cardiac necrosis/cell death. Functional assays conducted on Seahorse respirometer showed that cytokine-stimulated cells display decreased glycolytic and mitochondrial ATP production, dependency of fatty acid oxidation as well as increased proton leak and non-mitochondrial oxygen consumption. Together, our results suggest that IFN-gamma and TNF-alpha cause direct damage to cardiomyocytes' mitochondria by promoting oxidative and nitrosative stress and impairing energy production pathways. We hypothesize that treatment with agonists of AMPK, NRF2 and SIRT1 might be an approach to ameliorate the progression of Chagas disease cardiomyopathy.