ERIKA RABELO FORTE DE SIQUEIRA
Projetos de Pesquisa
Unidades Organizacionais
LIM/07 - Laboratório de Gastroenterologia Clínica e Experimental, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
- MTP-493G/T gene polymorphism is associated with steatosis in hepatitis C-infected patients(2012) SIQUEIRA, E. R. F.; OLIVEIRA, C. P. M. S.; CORREA-GIANNELLA, M. L.; STEFANO, J. T.; CAVALEIRO, A. M.; FORTES, M. A. H. Z.; MUNIZ, M. T. C.; SILVA, F. S.; PEREIRA, L. M. M. B.; CARRILHO, F. J.The reduction of hepatic microsomal transfer protein (MTP) activity results in fatty liver, worsening hepatic steatosis and fibrosis in chronic hepatitis C (CHC). The G allele of the MTP gene promoter, -493G/T, has been associated with lower transcriptional activity than the T allele. We investigated this association with metabolic and histological variables in patients with CHC. A total of 174 untreated patients with CHC were genotyped for MTP -493G/T by direct sequencing using PCR. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and had current and past daily alcohol intake lower than 100 g/week. The sample distribution was in Hardy-Weinberg equilibrium. Among subjects with genotype 1, 56.8% of the patients with fibrosis grade 3+4 presented at least one G allele versus 34.3% of the patients with fibrosis grade 1+2 (OR = 1.8; 95%CI = 1.3-2.3). Logistic regression analysis with steatosis as the dependent variable identified genotypes GG+GT as independent protective factors against steatosis (OR = 0.4, 95%CI = 0.2-0.8; P = 0.01). The results suggest that the presence of the G allele of MTP -493G/T associated with lower hepatic MTP expression protects against steatosis in our CHC patients.
- Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and high plasma homocysteine in chronic hepatitis C (CHC) infected patients from the Northeast of Brazil(2011) SIQUEIRA, Erika R. F.; OLIVEIRA, Claudia P. M. S.; MUNIZ, Maria T. C.; SILVA, Filipe; PEREIRA, Leila M. M. B.; CARRILHO, Flair J.Background/Aim: Hyperhomocysteinemia due to Methylenetetrahydrofolate Reductase (MTHFR) gene, in particular the C677T (Ala222Val) polymorphism were recently associated to steatosis and fibrosis. We analyzed the frequency of MTHFR gene in a cross-sectional study of patients affected by Chronic Hepatitis C (CHC) from Northeast of Brazil. Method: One hundred seven-four untreated patients with CHC were genotyped for the C677T MTHFR. Genomic DNA was extracted from peripheral blood cells and the C677T MTHFR polymorphism was identified by PCR-RFLP. The homocysteine (Hcy) levels were determined by chemiluminescence method. All patients were negative for markers of Wilson's disease, hemochromatosis and autoimmune diseases and have current and past daily alcohol intake less than 100 g/week. Results: Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8% versus 4.4% genotype 1 (p = 0.01). Nevertheless, association was found between the MTHFR genotype TT x CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p < 0.05). A significant difference was found on plasma Hcy levels in patients with steatosis regardless of HCV genotype (p = 0.03). Conclusion: Our results indicate that plasma Hcy levels is highly prevalent in subjects with chronic hepatits C with steatosis regardless of HCV genotype and vitamin deficiency. The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype TT+CT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis in CHC infected patients from the northeast of Brazil regardless of HCV genotype. The genetic susceptibility of MTHFR C677T polymorphism should be confirmed in a large population.
- Association of a variant in the regulatory region of NADPH oxidase 4 gene and metabolic syndrome in patients with chronic hepatitis C(2015) SIQUEIRA, Erika Rabelo Forte de; PEREIRA, Luciano Beltrao; STEFANO, Jose Tadeu; PATENTE, Thiago; CAVALEIRO, Ana Mercedes; VASCONCELOS, Luydson Richardson Silva; CARMO, Rodrigo Feliciano; PEREIRA, Leila Maria Moreira Beltrao; CARRILHO, Flair Jose; CORREA-GIANNELLA, Maria Lucia; OLIVEIRA, Claudia P.Background: Given the important contribution of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system to the generation of reactive oxygen species induced by hepatitis C virus (HCV), we investigated two single nucleotide polymorphisms (SNPs) in the putative regulatory region of the genes encoding NADPH oxidase 4 catalytic subunit (NOX4) and its regulatory subunit p22phox (CYBA) and their relation with metabolic and histological variables in patients with HCV. Methods: One hundred seventy eight naive HCV patients (49.3% male; 65% HCV genotype 1) with positive HCV RNA were genotyped using specific primers and fluorescent-labeled probes for SNPs rs3017887 in NOX4 and -675 T -> A in CYBA. Results: No association was found between the genotype frequencies of NOX4 and CYBA SNPs and inflammation scores or fibrosis stages in the overall population. The presence of the CA + AA genotypes of the NOX4 SNP was nominally associated with a lower alanine aminotransferase (ALT) concentration in the male population (CA + AA = 72.23 +/- 6.34 U/L versus CC = 100.22 +/- 9.85; mean +/- SEM; P = 0.05). The TT genotype of the CYBA SNP was also nominally associated with a lower ALT concentration in the male population (TT = 84.01 +/- 6.77 U/L versus TA + AA = 109.67 +/- 18.37 U/L; mean +/- SEM; P = 0.047). The minor A-allele of the NOX4 SNP was inversely associated with the frequency of metabolic syndrome (MS) in the male population (odds ratio (OR): 0.15; 95% confidence interval (CI): 0.03 to 0.79; P = 0.025). Conclusions: The results suggest that the evaluated NOX4 and CYBA SNPs are not direct genetic determinants of fibrosis in HCV patients, but nevertheless NOX4 rs3017887 SNP could indirectly influence fibrosis susceptibility due to its inverse association with MS in male patients.
- Plasmatic higher levels of homocysteine in Non-alcoholic fatty liver disease (NAFLD)(2013) CARVALHO, Sylene Coutinho Rampche de; MUNIZ, Maria Tereza Cartaxo; SIQUEIRA, Maria Deozete Vieira; SIQUEIRA, Erika Rabelo Forte; GOMES, Adriana Vieira; SILVA, Karina Alves; BEZERRA, Lais Carvalho Luma; D'ALMEIDA, Vania; OLIVEIRA, Claudia Pinto Marques Souza de; PEREIRA, Leila Maria M. BeltraoBackground: Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease, which includes a spectrum of hepatic pathology such as simple steatosis, steatohepatitis, fibrosis and cirrhosis. The increased serum levels of homocysteine (Hcy) may be associated with hepatic fat accumulation. Genetic mutations in the folate route may only mildly impair Hcy metabolism. The aim of this study was to investigate the relation between liver steatosis with plasma homocysteine level and MTHFR C677T and A1298C polymorphisms in Brazilian patients with NAFLD. Methods: Thirty-five patients diagnosed with NAFLD by liver biopsy and forty-five healthy controls neither age nor sex matched were genotyped for C677T and A1298C MTHFR polymorphisms using PCR-RFLP and PCR-ASA, respectively, and Hcy was determined by HPLC. All patients were negative for markers of Wilson's, hemochromatosis and autoimmune diseases. Their daily alcohol intake was less than 100 g/week. A set of metabolic and serum lipid markers were also measured at the time of liver biopsies. Results: The plasma Hcy level was higher in NAFLD patients compared to the control group (p = 0.0341). No statistical difference for genotypes 677C/T (p = 0.110) and 1298A/C (p = 0.343) in patients with NAFLD and control subjects was observed. The genotypes distribution was in Hardy-Weinberg equilibrium (677C/T p = 0.694 and 1298 A/C p = 0.188). The group of patients and controls showed a statistically significant difference (p < 0.001) for BMI and HOMA_IR, similarly to HDL cholesterol levels (p < 0,006), AST, ALT, gamma GT, AP and triglycerides levels (p < 0.001). A negative correlation was observed between levels of vitamin B12 and Hcy concentration (p = 0.005). Conclusion: Our results indicate that plasma Hcy was higher in NAFLD than controls. The MTHFR C677T and A1298C polymorphisms did not differ significantly between groups, despite the 677TT homozygous frequency was higher in patients (17.14%) than in controls (677TT = 4.44%) (p > 0.05). The suggested genetic susceptibility to the MTHFR C677T and A1298C should be confirmed in large population based studies.