Nitric oxide and pro-inflammatory cytokines in acute hepatitis B

Association of TNF-α Gene Polymorphisms with Production of Protein and Susceptibility to Chronic Hepatitis B Infection in the South East Iranian Population

BACKGROUND

The host genetic background regulates the natural history of chronic hepatitis B virus (HBV) infection.

OBJECTIVES

The aim of this study was to investigate the association between TNF-α gene polymorphism in the promoter region and susceptibility to chronic hepatitis B virus infection.

METHODS

Four polymorphisms of TNF-α gene including -238 A/G, -308 A/G, -857 C/T, and -863 A/C were analyzed by PCR-RFLP in 100 chronic HBV infected patients (HBV group), 40 spontaneously recovered HBV subjects (SR group), and 100 healthy controls (C group). Also, serum levels of protein were monitored.

RESULTS

The study showed that the existence of -308 G, -857 C, and -863 A alleles significantly increased susceptibility to chronic HBV infection. In addition, GGCA haplotype had a higher frequency in HBV patients than C and SR groups that might be related to the natural history of the infection. Chronic HBV patients with -308 GG, -857 CC, and -863 AA genotypes had lower serum levels of TNF-α compared to those with other genotypes.

CONCLUSIONS

The results indicated that there was a positive association between susceptibility to chronic HBV infection and TNF-α polymorphism. In addition, HBV patients carrying -308 GG, -857 CC, and -863 AA genotypes with lower serum levels of TNF-α had an increased risk of infection.

Effects of IL-1β, IL-6 and IL-8 on erythrocytes, platelets and clot viscoelasticity

Complex interactions exist between cytokines, and the interleukin family plays a fundamental role in inflammation. Particularly circulating IL-1β, IL-6 and IL-8 are unregulated in systemic and chronic inflammatory conditions. Hypercoagulability is an important hallmark of inflammation, and these cytokines are critically involved in abnormal clot formation, erythrocyte pathology and platelet hyper-activation, and these three cytokines have known receptors on platelets. Although these cytokines are always unregulated in inflammation, we do not know how the individual cytokines act upon the structure of erythrocytes and platelets, and which of the viscoelastic clot parameters are changed. Here we study the effects of IL-1β, IL-6 and IL-8 at low physiological levels, representative of chronic inflammation, by using scanning electron microscopy and thromboelastography. All three interleukins caused the viscoelastic properties to display an increased hypercoagulability of whole blood and pathology of both erythrocytes and platelets. The most pronounced changes were noted where all three cytokines caused platelet hyper-activation and spreading. Erythrocyte structure was notably affected in the presence of IL-8, where the morphological changes resembled that typically seen in eryptosis (programmed cell death). We suggest that erythrocytes and platelets are particularly sensitive to cytokine presence, and that they are excellent health indicators.

Use of serum levels of proinflammatory cytokine IL-1alpha in chronic hepatitis B

Background:

The reasons for the chronic viral persistence of hepatitis B virus infection (HBV) are unknown, but are probably related to host immune factors. Cytokines play a significant role in immune defense. Interleukin-1 (IL-1) is a proinflammatory cytokine and some studies have demonstrated that IL-1 production was impaired in patients with chronic infections of hepatitis B virus, implying that IL-1 may play a role in viral clearance, progression of fibrosis and in malignant potential of HBV. In this study, along with routine laboratory tests, has been performed the analysis of serum levels of proinflammatory cytokine IL-1 α in order of better understanding and monitoring of chronic hepatitis B.

Objective:

The aim of this study was to analyze the usefulness of laboratory tests, which are routinely used in the assessment of liver disease with specified immunological parameters in patients with chronic hepatitis B.

Patients and methods:

Total of 60 subjects was divided into two groups: HBV- PCR positive and negative group. The control group of 30 healthy participants was included. Apart from standard laboratory tests, the analysis included serum levels of cytokine IL-1 α.

Results and discussion:

IL-1α had the highest mean concentration in group 1–viral hepatitis C, with PCR positive test (5.73 pg / ml), and then in group 2- viral hepatitis B, PCR negative test (5.39 pg / ml). ANOVA test proves that IL-1α in the healthy group (3) was different from other groups as follows: in relation to group 1 statistical significance level was p <0.001 (F = 32 75 5); in relation to group 2 was also statistically significant at p <0.001 (F = 182 361); Cytokine IL-1 was statistically analyzed separately and compared by group 1 and 2 using Student t-test for independent samples. Statistical significance was observed at p = 0.026. IL-1 α was positively correlated with the duration of the illness (p <0.01) and with serum ALT activity (p <0.01) and serum AST activity (p <0.01). Using multivariate analysis model “Factor Analysis”, was made significant stratification predictive parameters in relation to the cytokine IL-1α, stratified significance is indicated as follows: 1. Age, 2. history of receiving transfusions, 3. ALT, 4. AST, 5. MELD score (negative), 6. Child-Pugh score (Negative).

Conclusion:

IL-1α was significantly elevated in inflammatory conditions of pronounced activity (PCR positive hepatitis). IL-1α may have important role as marker of both inflammation and hepatic injury, particularly in the course of hepatitis B. Results suggest that inflammatory and immune parameters, analyzed together can significantly contribute to the understanding and predicting of chronic liver damage. IL-1 can be used as important parameter of inflammatory activity and fibrosis evaluation and eventually prediction of malignant transformation in chronic liver damage.

The TNF-α -308 Promoter Gene Polymorphism and Chronic HBV Infection

Background and Aims. TNF-α -308 allele promoter polymorphism has been known to be a potential prognostic factor in patients with chronic HBV infection. We tried to determine how TNF-α -308 allele promoter polymorphism would affect the prognosis in patients with chronic HBV infection. Methods. We searched MEDLINE, EMBASE, and reference lists of relevant review articles related to the association between “TNF-α G-308A promoter polymorphism” with “chronic HBV infection”. We only focused on searching -308 locus in published studies. We reviewed 21 original articles about TNF-α -308 allele polymorphism and its effect on prognosis in patients with chronic HBV infection and discussed the results. Results. conflicting results were observed. The results were divided into 3 groups including neutral, negative, and positive associations between TNF-α -308 allele polymorphism and prognosis in patients with chronic HBV infection. We summarized the primary data as a table. Conclusions. Authors concluded that although there is an upward trend in evidence to claim that there is a positive relation between TNF-α G-308A promoter polymorphisms and resolution of chronic HBV infection, due to many biases and limitations observed in reviewed studies, an organized well-designed study is needed for clarifying the real association.

Evaluation of genetic susceptibility loci for chronic hepatitis B in Chinese: two independent case-control studies

BACKGROUND

A recent genome-wide scan has identified two genetic variants in the HLA-DP region strongly associated with hepatitis B infection in Japanese. This study evaluates the effects of these risk variants in Chinese, where the HBV infection is the most popular in the world.

METHODS AND FINDINGS

We have assessed the relationship between these two single nucleotide polymorphisms (rs3077 and rs9277535) and chronic hepatitis B infection in two independent case-control studies. The first population in Chinese Han included 736 patients and 782 spontaneously recovered controls. The second set was established in Chinese Zhuang minority of 177 patients and 208 controls. Both A alleles of rs3077 and rs9277535 significantly deceased the risk to CHB in Chinese Han (OR = 0.540, 95%CI: 0.464-0.628, P = 4.068×10(-16) and OR = 0.696, 95%CI: 0.601-0.806, P = 1.062×10(-6), respectively). Conceivably, rs9277535 was found to be associated with decreased risk of the disease in Chinese Zhuang, with an OR of 0.606 (95%CI, 0.441-0.833, P = 0.002).

CONCLUSION

Chronic hepatitis B susceptibility loci in HLA-DP region (rs3077 and rs9277535) identified by genome-wide scan in Japanese population were validated in Chinese population. These findings might provide clues to develop screening and surveillance strategies.

Serum levels of soluble Fas, soluble tumor necrosis factor-receptor II, interleukin-2 receptor and interleukin-8 as early predictors of hepatocellular carcinoma in Egyptian patients with hepatitis C virus genotype-4

BACKGROUND

Liver disease progression from chronic hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) is associated with an imbalance between T-helper 1 and T-helper 2 cytokines. Evaluation of cytokines as possible candidate biomarkers for prediction of HCC was performed using soluble Fas(sFas), soluble tumor necrosis factor receptor-II (sTNFR-II), interleukin-2 receptor (IL-2R) and interleukin-8 (IL-8).

RESULTS

The following patients were recruited: 79 with HCV infection, 30 with HCC, 32 with chronic liver disease associated with elevated liver enzyme levels (with or without cirrhosis) in addition to 17 with chronic HCV with persistent normal alanine aminotransferase levels (PNALT). Nine normal persons negative either for HCV or for hepatitis B virus were included as a control group. All persons were tested for sFas, sTNFR-II, IL-2R and IL-8 in their serum by quantitative ELISA. HCC patients had higher levels of liver enzymes but lower log-HCV titer when compared to the other groups. HCC patients had also significantly higher levels of sFas, sTNFR-II and IL-2R and significantly lower levels of IL-8 when compared to the other groups. Exclusion of HCC among patients having PNALT could be predicted with 90 % sensitivity and 70.6 % specificity when sTNFR-II is [greater than or equal to] 389 pg/ml or IL-8 is < 290 pg/ml.

CONCLUSIONS

Serum TNFR-II, IL-2Ralpha and IL-8, may be used as combined markers in HCV-infected cases for patients at high risk of developing HCC; further studies, however, are mandatory to check these findings before their application at the population level.

Stimulation of inducible nitric oxide by hepatitis B virus transactivator protein HBx requires MTA1 coregulator

Nitric oxide has been implicated in the pathogenesis of inflammatory disorders, including hepatitis B virus-associated hepatocellular carcinoma. Transactivator protein HBx, a major regulator of cellular responses of hepatitis B virus, is known to induce the expression of MTA1 (metastasis-associated protein 1) coregulator via NF-kappaB signaling in hepatic cells. However, the underlying mechanism of HBx regulation of the inducible nitric-oxide synthase (iNOS) pathway remains unknown. Here we provide evidence that MTA1 is a positive regulator of iNOS transcription and plays a mechanistic role in HBx stimulation of iNOS expression and activity. We found that the HBx-MTA1 complex is recruited onto the human iNOS promoter in an NF-kappaB-dependent manner. Pharmacological inhibition of the NF-kappaB signaling prevented the ability of HBx to stimulate the transcription, the expression, and the activity of iNOS; nevertheless, these effects could be substantially rescued by MTA1 dysregulation. We further discovered that HBx-mediated stimulation of MTA1 is paralleled by the suppression of miR-661, a member of the small noncoding RNAs, recently shown to target MTA1. We observed that miR-661 controls of MTA1 expression contributed to the expression and activity of iNOS in HBx-expressing HepG2 cells. Accordingly, depletion of MTA1 by either miR-661 or siRNA in HBx-expressing cells severely impaired the ability of HBx to modulate the endogenous levels of iNOS and nitrite production. Together, these findings reveal an inherent role of MTA1 in HBx regulation of iNOS expression and consequently its function in the liver cancer cells.

Tumor necrosis factor-alpha 308.2 polymorphism is associated with advanced hepatic fibrosis and higher risk for hepatocellular carcinoma

BACKGROUND/AIMS

Host genetic factor and hepatic fibrosis may predispose to risk for hepatocellular carcinoma (HCC). This study aimed to assess the association between tumor necrosis factor (TNF) alpha polymorphism and hepatic fibrosis, and risk for HCC.

METHODS

One hundred eight pairs of gender-matched and age-matched patients with HCC and unrelated healthy controls were genotyped for TNF308.2 and TNF238.2 alleles with polymerase chain reaction and direct sequencing.

RESULTS

The frequency of TNF308.1/TNF308.2 genotype in cases was higher than that in controls [odds ratio (OR) = 4.37]. Multivariate analysis indicated that TNF308.2 allele (OR = 3.23), hepatitis B surface antigen (OR = 17.17), and antibodies to hepatitis C virus (OR = 45.52) were independent risk factors for HCC. Surrogate markers for significant fibrosis implied that cases with the TNF308.2 allele have more advanced liver fibrosis. Moreover, multivariate analysis indicated that cirrhosis with Child-Pugh grade C, low serum albumin, and low platelet count were independent risk factors for carrying the TNF308.2 allele.

CONCLUSIONS

TNF308.2 allele carriage and chronic hepatitis B virus/hepatitis C virus infection are independent risk factors for HCC. Carriage of the TNF308.2 allele correlates with disease severity and hepatic fibrosis, which may contribute to a higher risk for HCC.

Treatment with Y-40138, a multiple cytokine production modulator, inhibits lipopolysaccharide- or tumour necrosis factor-alpha-induced production of pro-inflammatory cytokines and augments interleukin-10

N-[1-(4-[4-(pyrimidin-2-yl)piperazin-1-yl]methyl phenyl)cyclopropyl] acetamide . HCl (Y-40138) suppresses liver injury in concanavalin A- and D-galactosamine/lipopolysaccharide (LPS)-induced mouse hepatitis models. However, the mechanism of action of Y-40138 has not been fully investigated. In this study, we examined the effect of Y-40138 on cytokine production in mice. Cytokine production was induced by intraperitoneal injection of LPS (0.5 mg kg(-1)) or intravenous injection of recombinant mouse tumour necrosis factor (TNF)-alpha (10 mug mouse(-1)) in BALB/c mice. TNF-alpha and interleukin (IL)-10 reached maximum levels 1.5 h after the LPS injection. IL-12 and interferon-sigma (IFN-sigma) reached maximum levels 3 to 9 h after the injection. When Y-40138 was orally administered 30 min prior to the injection, it inhibited TNF-alpha, IL-12 and IFN-sigma production and augmented IL-10 production. Y-40138 also inhibited IL-12 production and augmented IL-10 production in TNF-alpha-stimulated mice. In IL-10 knockout mice, Y-40138 inhibited TNF-alpha and IL-12 production 1.5 h after the LPS injection but not after 3 h or later, unlike in wild mice. In addition, TNF-alpha production was inhibited by Y-40138 at concentrations that could not augment IL-10 production. These data suggest that Y-40138 modulates pro-inflammatory cytokine production by both IL-10-dependent and -independent mechanisms.

Association of TNF-alpha promoter polymorphisms with the outcomes of hepatitis B virus infection in Chinese Han population

Host genetic factors and environment factors including hepatitis B virus (HBV) genotypes are widely studied for the different outcomes of HBV infection. Recent studies suggest that tumour necrosis factor-alpha (TNF-alpha) plays a pivotal role in the viral clearance and host immune response to HBV, and the capacity for TNF-alpha production in individuals is influenced by a major genetic component. In this study, we aimed to explore whether the single-nucleotide polymorphisms (SNPs) of TNF-alpha promoter are associated with the outcomes of HBV infection in the Chinese Han population. One hundred and forty-three spontaneously recovered HBV subjects and 196 chronic hepatitis B patients were recruited in this case-control study in the Beijing area of China. Polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) and sequence-specific primer-PCR (SSP-PCR) were used to detect the SNPs of five sites in the TNF-alpha promoter (-238G/A, -308G/A, -857C/T, -863C/A, -1031T/C). The frequency distributions of genotypes and haplotypes in two groups were analysed by EPI and EH programs. The presence of the -238GG genotype was significantly correlated with persistence of HBV infection (OR = 4.08, P = 0.02), and -857TT genotype appeared in relation to the spontaneous clearance of HBV (OR = 0.47, P = 0.03). Frequency of haplotype GGCCT (-238/-308/-857/-863/-1031) in the chronic HB group was significantly lower than that in spontaneously recovered group (P = 0.03), and frequencies of haplotypes GGCAT and GGTAT in the chronic HB group were significantly higher than those in the spontaneously recovered group (P = 0.0001, P = 0.0004). In conclusion, TNF-alpha promoter polymorphisms are independently associated with different outcomes of HBV infection.

Association of polymorphism of tumor necrosis factor-alpha gene promoter region with outcome of hepatitis B virus infection

AIM: To determine whether -238G/A and -857C/T polymor-phisms of tumor necrosis factor-alpha (TNF-α), gene promoter and hepatitis B (HB) viral genotypes were associated with outcomes of HBV infection.

METHODS: A total of 244 HBV self-limited infected subjects, 208 asymptomatic carriers, and 443 chronic HB patients were recruited to conduct a case-control study. TNF-α -238G/A and -857C/T gene promoter polymorphisms were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and HBV genotypes were examined by nested PCR.

RESULTS: The positive rate of HBV DNA in asymptomatic carrier group and chronic HB group was 46.6% and 49.9%, respectively. HBV genotype proportion among the asymptomatic carriers was 2.1% for genotype A, 25.8% for genotype B, 68.0% for genotype C, and 4.1% for genotype B+C mixed infection, and 0.9% for genotype A, 21.7% for genotype B, 71.5% for genotype C, 5.9% for genotype B+C mixed infection in chronic HB group. There was no significant difference in genotype distribution between the asymptomatic carrier group and chronic HB group (χ2 = 1.66, P = 0.647). The frequency of -238GG genotype in self-limited group was 95.1%, significantly higher than 90.7% in chronic HB group and 89.0% in asymptomatic carrier group (P = 0.041 and P = 0.016, respectively).The frequency of TNF-α-857 CC in chronic HB group was 79.7%, significantly higher than 64.4% in asymptomatic carrier group and 70.9% in self-limited group (P<0.001 and P = 0.023, respectively). A multiple logistic regression analysis revealed that TNF-α-238GA and -857CC were independently associated with chronic HB after gender and age were adjusted.

CONCLUSION: TNF-α promoter variants are likely to play a substantial role in the outcome of HBV infection.

The potential anti-HBV effect of amantadine in combination with ursodeoxycholic acid and biphenyl dimethyl dicarboxylate in HepG2 2.2.15 cells

Experimental studies have demonstrated that the triple combination of amantadine (A)/ ursodeoxycholic acid (UDCA, U)/ biphenyl dimethyl dicarboxylate (DDB, D) might have a preferential antiviral effect compared with that observed in interferon-induced antiviral signal pathways, such as those of STAT1alpha and the 6-16 genes. To confirm the result, this study examined whether the signal transduction for the antiviral activity in HepG2 2.2.15 was induced dependently or independently of interferon. To accomplish this, the correlation between the STAT1alpha and 6-16 genes, and nitric oxide, for the mediation of the antiviral activity was assessed. The increase in nitric oxide in the UDCA groups suggests that the inhibition of viral gene replication was enhanced by the amantadine combinations (AU and AUD), and might be more effective if incubated for longer periods. It was found that STAT1alpha was activated by the amantadine combination, although to a lesser extent than that of interferon-alpha, and the primary endpoints examined for the inhibition of gene expression (HBsAg and HBcAg) were remarkably well regulated. This suggests that the amantadine triple, or at least the double, combination had better clinical benefits than those of IFN-alpha and the nucleoside analogue single treatment. This demonstrates that the amantadine combination might be a substitute for the existing HBV therapy if the results of in vivo and in vitro studies concur.