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 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 39 Citação(ões) na Scopus
    Myocardial Infarction-Associated Transcript, a Long Noncoding RNA, Is Overexpressed During Dilated Cardiomyopathy Due to Chronic Chagas Disease
    (2016) FRADE, Amanda Farage; LAUGIER, Laurie; FERREIRA, Ludmila Rodrigues Pinto; BARON, Monique Andrade; BENVENUTI, Luiz Alberto; TEIXEIRA, Priscila Camillo; NAVARRO, Isabela Cunha; CABANTOUS, Sandrine; FERREIRA, Frederico Moraes; CANDIDO, Darlan da Silva; GAIOTTO, Fabio Antonio; BACAL, Fernando; POMERANTZEFF, Pablo; SANTOS, Ronaldo Honorato Barros; KALIL, Jorge; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Long noncoding RNAs (lncRNAs) modulate gene expression at the epigenetic, transcriptional, and posttranscriptional levels. Dysregulation of the lncRNA known as myocardial infarction-associated transcript (MIAT) has been associated with myocardial infarction. Chagas disease causes a severe inflammatory dilated chronic cardiomyopathy (CCC). We investigated the role of MIAT in CCC. A whole-transcriptome analysis of heart biopsy specimens and formalin-fixed, paraffin-embedded samples revealed that MIAT was overexpressed in patients with CCC, compared with subjects with noninflammatory dilated cardiomyopathy and controls. These results were confirmed in a mouse model. Results suggest that MIAT is a specific biomarker of CCC.
  • article 37 Citação(ões) na Scopus
    Whole-Genome Cardiac DNA Methylation Fingerprint and Gene Expression Analysis Provide New Insights in the Pathogenesis of Chronic Chagas Disease Cardiomyopathy
    (2017) LAUGIER, Laurie; FRADE, Amanda Farage; FERREIRA, Frederico Moraes; BARON, Monique Andrade; TEIXEIRA, Priscila Camillo; CABANTOUS, Sandrine; FERREIRA, Ludmila Rodrigues Pinto; LOUIS, Laurence; RIGAUD, Vagner Oliveira Carvalho; GAIOTTO, Fabio Antonio; BACAL, Fernando; POMERANTZEFF, Pablo; BOCCHI, Edimar; KALIL, Jorge; SANTOS, Ronaldo Honorato Barros; CUNHA-NETO, Edecio; CHEVILLARD, Christophe
    Background. Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects 10 million people worldwide. Approximately 12 000 deaths attributable to Chagas disease occur annually due to chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy presenting with heart failure and arrythmia; 30% of infected subjects develop CCC years after infection. Genetic mechanisms play a role in differential progression to CCC, but little is known about the role of epigenetic modifications in pathological gene expression patterns in CCC patients' myocardium. DNA methylation is the most common modification in the mammalian genome. Methods. We investigated the impact of genome-wide cardiac DNA methylation on global gene expression in myocardial samples from end-stage CCC patients, compared to control samples from organ donors. Results. In total, 4720 genes were differentially methylated between CCC patients and controls, of which 399 were also differentially expressed. Several of them were related to heart function or to the immune response and had methylation sites in their promoter region. Reporter gene and in silico transcription factor binding analyses indicated promoter methylation modified expression of key genes. Among those, we found potassium channel genes KCNA4 and KCNIP4, involved in electrical conduction and arrythmia, SMOC2, involved in matrix remodeling, as well as enkephalin and RUNX3, potentially involved in the increased T-helper 1 cytokine-mediated inflammatory damage in heart. Conclusions. Results support that DNA methylation plays a role in the regulation of expression of pathogenically relevant genes in CCC myocardium, and identify novel potential disease pathways and therapeutic targets in CCC.