Search

Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P=0.025 OR 2.25 CI 1.10-4.59 and P=0.032 OR 2.32 CI 1.07-5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV. [ABSTRACT FROM AUTHOR]

Abstract: Myeloperoxidase (MPO) is an enzyme responsible for generating hypochlorous acid and reactive oxidants that may lead to liver injury and cancer in hepatitis C (HCV) infection. MPO expression level is regulated by a polymorphism in the promoter region −463 of MPO gene. In the current study, MPO plasma levels and the G-463A MPO polymorphism were determined in 158 chronically HCV infected patients with and without hepatocellular carcinoma (HCC). MPO plasma levels were determined using a commercially ELISA kit. The G-463A MPO polymorphism was accessed by real time PCR using TaqMan probes. The MPO plasma levels of patients with HCV-HCC were higher in comparison to patients with chronic hepatitis or with those patients with severe fibrosis (p =0.01 and p =0.04, respectively). The MPO G-463A polymorphism was not associated with HCV outcome. These findings suggest MPO levels monitoring may be a potential biological marker to HCC screening in patients with HCV. [Copyright &y& Elsevier]

Abstract: Mannose binding lectin (MBL) is a molecule of the innate immunity, which activates the complement system and modulates inflammation. We investigated the association of the polymorphisms in the exon 1 and promoter region of the MBL gene (MBL2) with the susceptibility to hepatitis C virus (HCV) infection and the degree of liver fibrosis in Brazilian patients chronically infected with HCV. The study was performed in 232 healthy control subjects and 186 patients, 157 of whom underwent liver biopsy after histopathology analysis and classification of fibrosis according to Metavir score. Exon 1 was genotyped by melting temperature assay and the promoter region by Taqman real-time polymerase chain reacation. The frequency of genotypes related to low production of MBL was higher in patients with HCV than in controls (p c = 0.0001, odds ratio = 3.52; confidence interval = 1.86–6.71). In addition, the frequency of variant haplotype, HYO was higher in patients with the severe fibrosis stage F4 (10.7%) than in patients with the mild/moderate fibrosis stage F1/F2 (3.4%), when compared with the HYA haplotype (p c = 0.04, odds ratio = 5.25, confidence interval = 1.11–23.62). We conclude that MBL variant alleles expressing low levels of MBL are associated with the susceptibility to HCV infection and that the inheritance of HYO haplotype could be associated with fibrosis severity. [Copyright &y& Elsevier]

The complement system (CS) is a key element of immunity against pathogens but also seems to influence other events, such as tumorigenesis and tissue repair. Complement component 7 (C7) is a key component of the lytic pathway of CS, leading to the formation of the membrane attack complex (MAC). This study aimed to investigate the existence of the association of a polymorphism in the C7 gene, rs1063499, with hepatic fibrosis and the occurrence of hepatocellular carcinoma (HCC) in patients with hepatitis C. We analyzed 456 samples from patients with chronic hepatitis C. Real-time PCR was used for allelic discrimination. Patients were classified by their METAVIR score as F1 (n = 100), F2 (n = 83), F3 (n = 101) or F4 (n = 66); 106 patients were diagnosed with HCC. Patients carrying the G/G genotype of C7 had a lower chance of developing severe fibrosis in the recessive model (p = 0.042; OR: 0.65 95% CI 0.41–1.02). However, the G/G genotype frequency was higher in patients with HCC (P = 0.01; OR: 2.07 95% CI 1.20–3.53) and in those with larger tumors (p = 0.04). The G/G C7 genotype seems to be a protective factor against advanced fibrosis; however, it was associated with a higher risk of HCC and the occurrence of larger hepatic nodules, suggesting the involvement of C7 in the physiopathogenesis of HCC and fibrosis in patients with hepatitis C virus (HCV). [ABSTRACT FROM AUTHOR]

IL28B polymorphisms rs12979860 CC genotype was associated to protection of HCV infection and sustained virological response (SVR) in HCV infected patients treated with pegIFNα/ribavirin (IFNα/RIB), however, this polymorphism frequency varies depending on genetic components. Studies with larger number of Brazilian individuals, determining IL28B polymorphisms is lacking. Regarding to treatment response, the levels of IL10 seem to influence response to IFNα/RIB therapy. Thus, the IL28B polymorphism frequency was investigated in health controls and infected HCV patients, as well as, in patients who reach SVR vs Non-SVR. Also, to gain insight into the interplay between IL28B genotypes, IL10 levels and therapy response, a subgroup of genotyped HCV patients SVR and Non-SVR were analyzed regarding the IL10 production. Methods It was enrolled 487 HCV infected patients and 234 healthy individuals. Patients with response to IFNα/RIB were classified as SVR (n=81) and Non-SVR (n=123). TAQMAN probes were used for genotyping the SNP rs12979860, resulting in CC, CT or TT genotypes. In one hundred one patients, the levels IL10 were measured at week 4 of IFNα/RIB. Results CC genotype was associated to SVR (p=0.029) and its frequency was higher in healthy individuals vs patients (p=0.02). Patients carrying CT/TT with IL10<10pg/mL, had a chance of 2.72 to achieve SVR in multivariate model (p=0.043). Conclusion CC genotype was associated to SVR and protection to HCV infection. Moreover, IL28B genotyping and IL10 serum levels could be further explored as a useful algorithm for identify the CT/TT SVR patients. [ABSTRACT FROM AUTHOR]

Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors. [ABSTRACT FROM AUTHOR]