Chronic alcohol intoxication decreases the serum level of hepatitis B surface antigen in transgenic mice

The Effects of Alcohol on Other Chronic Liver Diseases

Alcohol consumption is often a comorbid condition in other chronic liver diseases. It has been shown to act in synergy to increase liver injury in viral hepatitis, hereditary hemochromatosis, and nonalcoholic fatty liver disease (NAFLD), leading to an increased risk of cirrhosis, hepatocellular carcinoma, and liver-related mortality. Data suggest that modest alcohol consumption may be inversely related to the risk of developing NAFLD and lower rates of progression of NAFLD to nonalcoholic steatohepatitis (NASH). This article reviews data on the relationship between alcohol consumption and other chronic liver diseases.

Update on Alcohol and Viral Hepatitis

Alcohol consumption is often associated with viral hepatitis. Although alcohol is known to worsen viral liver disease, the interactions between alcohol and viral hepatitis are not fully understood. Molecular alterations in the liver due to alcohol and viral hepatitis include effects on viral replication, increased oxidative stress, cytotoxicity, and a weakened immune response. Clinically, alcohol enhances disease progression and favors induction of primitive liver neoplasm. The use of new antivirals for hepatitis C and well-established drugs for hepatitis B will determine how viral hepatitis can be controlled in a large percentage of these patients. However, alcohol-related liver disease continues to represent a barrier for access to antivirals, and it remains an unresolved health issue.

Update on Alcohol and Viral Hepatitis

Alcohol consumption is often associated with viral hepatitis. Although alcohol is known to worsen viral liver disease, the interactions between alcohol and viral hepatitis are not fully understood. Molecular alterations in the liver due to alcohol and viral hepatitis include effects on viral replication, increased oxidative stress, cytotoxicity, and a weakened immune response. Clinically, alcohol enhances disease progression and favors induction of primitive liver neoplasm. The use of new antivirals for hepatitis C and well-established drugs for hepatitis B will determine how viral hepatitis can be controlled in a large percentage of these patients. However, alcohol-related liver disease continues to represent a barrier for access to antivirals, and it remains an unresolved health issue.

[Definition, diagnosis, and prevalence of occult hepatitis B virus infection]

Occult HBV infection is characterized by the absence of serum HBsAg with persistence of low level of intrahepatic HBV DNA. Several suggested mechanisms for the origin of occult HBV infection include strong suppression of viral replication and gene expression, mutation in the regulatory regions of HBV genome, formation of immunoglobulin-bound HBsAg, viral interference, and blockage of HBsAg secretion from infected hepatocytes. Standardized assays are not yet available, and sensitive HBV DNA amplification assay is necessary for the diagnosis of cryptic infection. Detection rate of HBV DNA is highest in IgG anti-HBc positive population. However, neither anti-HBc nor anti-HBs can be detected in a significant proportion of infected persons. Occult HBV infection occurs in a number of clinical settings and is highly prevalent in HCV-infected patients as well as in patients with cryptogenic chronic liver disease including hepatocellular carcinoma.

Ethanol potentiates hepatitis B virus replication through oxidative stress-dependent and -independent transcriptional activation

Excessive alcohol intake accelerates disease progression in chronic hepatitis B virus (HBV) infection, but the mechanisms by which ethanol worsens the prognosis of chronic hepatitis B (CHB) are not fully understood. The aim of this study was to investigate whether HBV replication is augmented by alcohol or alcohol-induced cytochrome p450 2E1 (CYP2E1), and if so, whether oxidative stress is involved in the process. Ethanol treatment promoted HBV replication in HepAD38 cells that permit the conditional viral replication. Luciferase reporter assays confirmed that HBV core, preS1 and preS2/S promoter activities were augmented by ethanol. Ethanol did not induce oxidative stress in HepAD38 cells with minimal expression of CYP2E1. However, over-expression of CYP2E1 induced oxidative stress and amplified transcriptional activation of HBV by ethanol. Antioxidant glutathione treatment attenuated CYP2E1-mediated augmentation of HBV replication in ethanol-treated cells. In conclusion, ethanol enhances transcriptional activity of HBV promoters in human hepatoma cells in an oxidative stress-independent manner; and CYP2E1-mediated oxidative stress potentiates the ethanol-induced transactivation of HBV.

[Occult hepatitis B: prevalence and clinical characteristics in a population with high endemicity of hepatitis B infection in the western Brazilian Amazon region]

A persistent form of the hepatitis B virus called occult chronic hepatitis B has recently been described. Its prevalence and physiopathology are unknown. The aim of this study was to evaluate the occurrence of this clinical entity among patients in the Brazilian Amazon region. Out of 51 anti-HBc total-positive patients who were tested using the polymerase chain reaction, 17% were positive. We did not find any associations with classical risk factors for hepatitis B virus infection or with biochemical tests, hematological tests or histological patterns. However, the jaundiced and HIV-positive patients showed a statistical association with the presence of hepatitis B virus-DNA. The results demonstrated that occult hepatitis B occurred among our patients, but at prevalence rates lower than expected for this region. We believe that despite the small sample size, the occurrence might have been found to be greater if we had used primers for the S, C and X regions of the hepatitis B virus genome, thereby increasing the sensitivity of the test.

Positive CAGE screen correlates with cirrhosis in veterans with chronic hepatitis C

The current study examines the relationship between problem alcohol use and severity of liver disease by self-administered questionnaires using both the CAGE questionnaire and beverage-specific quantity-frequency questions. The cohort consisted of 38 patients with cirrhosis (10 with decompensated liver disease) and 62 with mild fibrosis (stage 0-1), of comparable mean age and estimated duration of infection. Although mean alcohol consumption was similar in both groups, a positive CAGE screen (defined as two or more affirmative answers) was significantly more common among cirrhotics (OR = 5.24; 95% CI, 1.78-15.39) and tended to be associated with decompensated liver disease (OR = 13.3; 95% CI, 0.67-256) among cirrhotics. In multivariate analysis, only inflammatory grade on liver biopsy (OR = 67.7; 95% CI, 10.6-431) and positive CAGE score (OR = 8.09; 95% CI, 1.15-57.1) were independent predictors of cirrhosis. These findings suggest that the CAGE questionnaire predicts advanced liver disease better than daily or lifetime drinking measures.

Study of hepatitis B (HB) vaccine non-responsiveness among health care workers from an endemic area (Taiwan)

OBJECTIVE

To evaluate the etiology of non-responsiveness to hepatitis B (HB) vaccination in adults from an endemic area.

METHODS

A total of 250 subjects who were HBsAg negative and anti-HBs<10 mIU/ml received three-dose HB-vaccine series. Anti-HBs 'negative' was defined as a level<1.5 mIU/ml. 'Weakly' positive was defined as 1.5-10 mIU/ml at pre-vaccination testing. Anti-HBs response was defined as a level >10 mIU/ml at post-vaccination testing. Among non-responders who were anti-HBc positive, serum anti-HBe and hepatitis B virus (HBV) DNA were tested.

RESULTS

Three variables were associated with non-responsiveness by univariate analysis: anti-HBc positive, male gender, and age >40 years. Multivariate analysis additionally showed that anti-HBs negative was associated with non-responsiveness. Among 23 non-responders in anti-HBc positive subjects, post-vaccination serum was available in 16 subjects. HBV-DNA in all subjects was under detectable level by PCR assay. Anti-HBe positive were found in 13 of 16 subjects and were assumed to be occult HBV infection.

CONCLUSION

Male gender, age >40 years and anti-HBc positive are associated with non-responsiveness to HB vaccination. Most of non-responders among anti-HBc positive subjects were assumed to be occult HBV infection. Subjects with weakly positive anti-HBs were associated with responsiveness which may be the effect of immune memory.

Analysis of risk factors for hepatocellular carcinoma in patients with HBs antigen- and anti-HCV antibody-negative alcoholic cirrhosis: clinical significance of prior hepatitis B virus infection

BACKGROUND

The hepatitis B virus (HBV) or hepatitis C virus (HCV) markers frequently are detected in alcoholic patients with hepatocellular carcinoma (HCC). However, risk factors for the development of HCC in patients with HBs antigen (Ag)- and anti-HCV antibody (anti-HCV)-negative alcoholic cirrhosis have not been clearly documented. The present study was conducted to elucidate the occurrence rates of HCC in HBs Ag- and anti-HCV-negative male alcoholic cirrhosis and to assess the risk factors for hepatocellular carcinogenesis.

METHOD

We prospectively studied 91 consecutive patients with HBs Ag- and anti-HCV-negative alcoholic cirrhosis for 0.5 to 12.5 years (median 5.9 years). Potential risk factors assessed for liver carcinogenesis included the following six variables: age, total alcohol intake, association of continuing alcohol intake after diagnosis, indocyanine green retention rate at 15 min, anti-HB core antibodies (anti-HBc), and association of diabetes mellitus.

RESULTS

Cumulative occurrence rates of HCC were 6.4%, 18.9%, and 28.7% at the end of the 5th, 7th and 10th years, respectively. When classified by anti-HBc, the occurrence rates of HCC in 31 patients with anti-HBc and 60 patients without anti-HBc were 15.6% and 2.9% at the 5th year, 28.4% and 13.5% at the 7th year, and 40.4% and 22.1% at the 10th year, respectively. The occurrence rates of HCC were also significantly related to the cumulative alcohol intake. Cox proportional hazard model identified that cumulative alcohol intake (p = 0.0047) and positive anti-HBc antibodies (p = 0.0598) were independently associated with the occurrence rates of HCC.

CONCLUSION

These epidemiologic results suggest that heavy cumulative alcohol intake and prior exposure to HBV infection are risk factors for the development of HCC in patients with HBs Ag- and anti-HCV-negative alcoholic cirrhosis.

[Peripheral markers, future perspectives]

Four of the recently described peripheral markers of alcohol abuse have been reviewed. The acetaldehyde adducts allow to detect an alcohol abuse lasting for several weeks, even after a recent alcohol withdrawal. Inversely, 5-hydroxytryptophol (5-HTOL) reflects the alcohol consumption of the last 24 hours. Its detection is possible after the blood alcohol concentration has disappeared. Its measurement is run in urine samples, thus without invasive sampling. The hyaluronic acid and the activity of beta-hexosaminidase are markers of hepatobiliary alcohol induced disorders more than direct markers of alcohol intake. Acetaldehyde adducts could be used as markers of long term alcohol abuse, CDT as a marker of the recent alcohol abuse, and 5-HTOL the detection of alcohol abuse of the past day.

Effects of ethanol on hepatitis B virus Pre-S/S gene expression in the human hepatocellular carcinoma derived HEP G2 hepatitis B DNA positive cell line

BACKGROUND/AIMS

Among the reported interactions between ethanol and hepatitis B virus (HBV), studies of transgenic mice have suggested an effect of ethanol on the secretion of viral envelope proteins.

METHODS

We further investigated these interactions in vitro by determining HBs antigen levels and performing northern blots of viral mRNA in human cell culture (HepG2 HBV positive cells) exposed for 3 to 12 days to various concentrations of ethanol.

RESULTS

In cultures exposed to 200 mM ethanol, HBs antigen concentrations increased in the medium (p < 0.05) after 3 days as Pre-S1 and Pre-S2 protein concentrations. This increase was not specific, as albumin and ferritin increased in the same proportions. Ethanol also increased the HBs antigen concentration in the cells (p < 0.05), whereas levels of viral mRNA encoding surface proteins were unaffected.

CONCLUSIONS

These findings show that short-term ethanol exposure in vitro can induce HBs antigen overexpression via a post-transcriptional mechanism.