Navegando por Autor "Rocha, José Luiz Marques"

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Biomarcadores inflamatórios e determinantes da síndrome metabólica em adultos jovens saudáveis
(Universidade Federal de Viçosa, 2012-02-03) Rocha, José Luiz Marques; Oliveira, Leandro Licursi de; http://lattes.cnpq.br/0578231392218162; Nascimento, Moysés; http://lattes.cnpq.br/6544887498494945; Bressan, Josefina; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781728Y2; http://lattes.cnpq.br/7179771155975755; Barbosa, Kiriaque Barra Ferreira; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4764361J8
Várias doenças crônicas são acompanhadas por processos inflamatórios e evidências continuam a se acumular sobre a relevância clínica dos preditores laboratoriais destes eventos fisiopatológicos. Neste contexto, o presente estudo se propôs a avaliar, em indivíduos jovens e clinicamente saudáveis, as concentrações plasmáticas de TNF-α e IL-6 e a expressão de genes relacionados ao processo inflamatório (TNF-α, IL-6, ICAM1, IL1R1 e IL-18) e suas possíveis associações com fatores de risco para o desenvolvimento da síndrome metabólica (SM). Foram avaliados 161 indivíduos quanto à antropometria, composição corporal, ingestão dietética, além de dados bioquímicos e clínicos. A dosagem plasmática de TNF-α e IL-6 foi realizada por ensaio imunológico (ELISA) em plasma EDTA. A expressão gênica (EG) relativa foi feita em células mononucleares (PBMC) utilizando-se PCR em tempo real. As comparações entre grupos foram feitas mediante os testes de Mann-Whitney-U ou Student-t, de acordo com a distribuição das variáveis. Foram utilizados a correlação de Spearman e modelos de regressão linear e logística rastrear associações e fatores preditivos relativos aos biomarcadores e aos componentes da SM. Os resultados foram apresentados como média ± DP com intervalo de confiança de 95% e nível de significância estatística de P<0,05. Os resultados revelaram que as concentrações plasmáticas de TNF-α e IL-6 foram superiores nos indivíduos do sexo masculino (P<0,001), contrariamente aos valores de EG que não se diferenciaram entre os gêneros. Os indivíduos com maiores níveis circulantes (MNC) de TNF-α também apresentaram maiores valores de peso corporal, perímetro da cintura, relação cintura/quadril, massa livre de gordura, pressão arterial sistólica e diastólica, glicose e ácido úrico sanguíneos e por outro lado, menores valores da % de gordura total, colesterol total e frações HDL-c e LDL-c (P<0,05). Já os indivíduos com MNC de IL-6 demonstraram maiores valores de peso corporal, IMC, gordura troncular, massa livre de gordura, pressão arterial sistólica e diastólica, fração HDL-c e ácido úrico, por outro lado, menores valores de % de gordura total, pregas cutâneas tricipital e bicipital, triacilgliceróis, colesterol total e fração LDL-c (P<0,05). A EG desta citocina se apresentou de forma inversa às concentrações plasmáticas de IL-6 (P=0,03). Indivíduos com MNC de TNF-α consumiam mais calorias, proteínas, cobre e fibras, no entanto menos ferro na dieta (P<0,05). Já aqueles com MNC de IL-6 consumiam mais calorias,macronutrientes, fibras, ferro e cobre (P<0,05). Mediante análise de regressão simples, observou-se que a EG de ICAM1, do IL1R1 e da IL-18 tiveram efeito preditivo positivo sobre os níveis circulantes de TNF-α (P< 0,05). Os indivíduos que se posicionaram nos dois maiores tercis (3,48 a 5,08 pg/mL e ≥ 5,09 pg/mL) da distribuição dos níveis circulantes do TNF-α, quando comparados àqueles no menor tercil, demonstraram aumento importante nas chances de apresentar obesidade abdominal (P<0,05). Da mesma forma, aqueles que se posicionaram no maior tercil, quando comparados àqueles no menor, demonstraram aumento importante nas chances de apresentar níveis reduzidos deHDL-c. Quando a mesma análise foi feita para IL-6, verificou-se que os indivíduos que se posicionaram nos dois maiores tercis (3,43 a 4,86 pg/mL e ≥ 4,87 pg/mL) da distribuição dos níveis circulantes desta citocina, quando comparados àqueles no menor tercil, mostraram aumento importante nas chances de apresentar concentrações séricas diminuídas de HDL-c. Este estudo contribuiu para o melhor entendimento das associações entre os marcadores de interesse e os fatores de risco para a ocorrência das doenças associadas à SM. E ainda, evidenciou a associação da EG de alguns marcadores inflamatórios em PBMC com variáveis importantes no contexto das doenças metabólicas, mesmo em adultos saudáveis.
Epigenetic mechanisms involved in the interaction between diet and the expression of inflammation-related genes
(Universidade Federal de Viçosa, 2016-02-19) Rocha, José Luiz Marques; Bressan, Josefina; http://lattes.cnpq.br/7179771155975755
Epigenetic mechanisms are involved in the regulation of gene expression including microRNAs (miRNA) and DNA methylation; and play a crucial role in the development and maintenance of pathophysiological complications. Therefore, the aims of this work were: 1) To evaluate the effect of a weight loss strategy based on the Mediterranean dietary pattern (RESMENA diet) on expression of some selected inflammation-related genes and miRNAs in white blood cells (WBC) of individuals with metabolic syndrome (MetS); 2) To clarify in vitro the roles of selected miRNAs on the expression of inflammation-related genes in human acute monocytic leukemia cells (THP-1). Moreover, we investigated the regulatory role of fatty acids (palmitic acid, oleic acid, eicosapentaenoic acid and docosahesaenoic acid) on the expression of these miRNAs in monocytes, macrophages and LPS-activated macrophages (AcM); 3) To explore in young and apparently healthy adults, the relation between DNA methylation levels of LINE-1, TNF and IL6 in periferal blood monoclear cells (PBMC) and anthropometric, biochemical, clinical, dietary, inflammatory and oxidative stress parameters. To the first aim, the clinical, anthropometric, and biochemical characteristics of 40 individuals with MetS (20 men, 20 women; age: 48.8±10.02y; BMI: 35.41±4.42 kg/m 2 ) were evaluated before and after an 8 weeks hypocaloric (-30% of energy requeriments) diet based on the Mediterranean dietary pattern. Food consumption and nutrient intake were assessed with a food frequency questionnaire and 48-h weighed food records. Total RNA was isolated from WBC and the expression of some inflammation-related miRNAs and mRNAs (IL-6, TNF, ICAM-1, IL-18, SERPINE1, VCAM-1) was assessed by qRT- PCR. To achieve the second aim, THP-1 were differentiated into macrophages and activated with LPS for 24 hours. The three cell types were transfected with miR-Let-7b- 5p and miR-155-3p mimics or negative control. qRT-PCR analyses were performed to evaluate selected genes with potential role in inflammatory pathways related to these miRNAs. To the third aim, one hundred fifty-six individuals (91 women, 65 men; age: 23.1±3.5 years; BMI: 22.0±2.9 kg/m 2 ) were evaluated for anthropometric, biochemical and clinical markers, including some components of the antioxidant defense system and inflammatory response. Moreover, DNA methylation of LINE-1, TNF and IL6 and the expression of some inflammation-related genes were analyzed in PBMC. The RESMENA nutritional intervention improved mostly anthropometric and biochemical features. The expression of miR-155-3p was decreased in PBMC, whereas let-7b was strongly upregulated as a consequence of the diet treatment. However, they were not correlated with the expression of the pro inflammatory genes in the same cells. The changes in the expression of let-7b, miR-125b, miR-130a, miR-132-3p, and miR-422b were associated with changes in diet quality when assessed by the Healthy Eating Index. Moreover, low consumption of lipids and saturated fat were associated with higher expression of let-7b after the nutritional intervention. The in vitro transfection of miR-155-3p mimic led to upregulation of IL6 in the three cell types analyzed. In the same way, SERPINE1 was upregulated in monocytes and macrophages. However, TLR-4 was downregulated in transfected monocytes and macrophages. After transfection with let-7b mimic, TNF/IL6 and SERPINE1 expression were downregulated in monocytes and AcM, respectively; however, TNF, IL6 and SERPINE1 were upregulated in macrophages. In addition, oleic acid was able to increase the expression of miR-155 in monocytes when compared with the DHA treatment but not in relation with non-treated cells. On the other side, oleic acid increased the expression of Let-7b in macrophages and AcM. Finally, the results from DNA methylation in young adults showed that adiposity was lower among individuals with higher LINE-1 methylation. On the contrary, body fat-free mass was higher among those with higher LINE-1 methylation. Individuals with higher LINE-1 methylation had higher daily intakes of calories, iron and riboflavin. However, those individuals who presented lower percentages of LINE-1 methylation reported higher intakes of copper, niacin and thiamin. Interestingly, the group with higher LINE-1 methylation had a lower percentage of current smokers and more individuals practicing sport. On the other hand, TNF methylation percentage was negatively associated with waist circumference, waist-to-hip ratio and waist-to-height ratio. Our data suggest that the modulation of the expression of miRNAs and DNA methylation through a nutrition approach might be a future alternative or adjunct to current pharmacologic therapy targeting endogenous miRNAs or target genes. Furthermore, this study also expands the understanding of the role of fatty acids in the epigenetic regulation in immune cells.