Effects of Alcohol Consumption on Histological Changes in Chronic Hepatitis C: A Clinicopathological Study

Ethanol enhances hepatitis C virus replication through lipid metabolism and elevated NADH/NAD+

Ethanol has been suggested to elevate HCV titer in patients and to increase HCV RNA in replicon cells, suggesting that HCV replication is increased in the presence and absence of the complete viral replication cycle, but the mechanisms remain unclear. In this study, we use Huh7 human hepatoma cells that naturally express comparable levels of CYP2E1 as human liver to demonstrate that ethanol, at subtoxic and physiologically relevant concentrations, enhances complete HCV replication. The viral RNA genome replication is affected for both genotypes 2a and 1b. Acetaldehyde, a major product of ethanol metabolism, likewise enhances HCV replication at physiological concentrations. The potentiation of HCV replication by ethanol is suppressed by inhibiting CYP2E1 or aldehyde dehydrogenase and requires an elevated NADH/NAD(+) ratio. In addition, acetate, isopropyl alcohol, and concentrations of acetone that occur in diabetics enhance HCV replication with corresponding increases in the NADH/NAD(+). Furthermore, inhibiting the host mevalonate pathway with lovastatin or fluvastatin and fatty acid synthesis with 5-(tetradecyloxy)-2-furoic acid or cerulenin significantly attenuates the enhancement of HCV replication by ethanol, acetaldehyde, acetone, as well as acetate, whereas inhibiting beta-oxidation with beta-mercaptopropionic acid increases HCV replication. Ethanol, acetaldehyde, acetone, and acetate increase the total intracellular cholesterol content, which is attenuated with lovastatin. In contrast, both endogenous and exogenous ROS suppress the replication of HCV genotype 2a, as previously shown with genotype 1b.

CONCLUSION

Therefore, lipid metabolism and alteration of cellular NADH/NAD(+) ratio are likely to play a critical role in the potentiation of HCV replication by ethanol rather than oxidative stress.

Redox regulation of hepatitis C in nonalcoholic and alcoholic liver

Hepatitis C virus (HCV) is an RNA virus of the Flaviviridae family that is estimated to have infected 170 million people worldwide. HCV can cause serious liver disease in humans, such as cirrhosis, steatosis, and hepatocellular carcinoma. HCV induces a state of oxidative/nitrosative stress in patients through multiple mechanisms, and this redox perturbation has been recognized as a key player in HCV-induced pathogenesis. Studies have shown that alcohol synergizes with HCV in the pathogenesis of liver disease, and part of these effects may be mediated by reactive species that are generated during hepatic metabolism of alcohol. Furthermore, reactive species and alcohol may influence HCV replication and the outcome of interferon therapy. Alcohol consumption has also been associated with increased sequence heterogeneity of the HCV RNA sequences, suggesting multiple modes of interaction between alcohol and HCV. This review summarizes the current understanding of oxidative and nitrosative stress during HCV infection and possible combined effects of HCV, alcohol, and reactive species in the pathogenesis of liver disease.

Mechanisms of synergy between alcohol and hepatitis C virus

BACKGROUND

Since the discovery of the hepatitis C virus (HCV), extensive literature has emerged on alcohol and HCV interaction.

GOAL

To understand the impact of alcohol and HCV infection on the severity of liver disease and the mechanisms of interaction between the two.

STUDY

Of 1269 articles (1991 to 2006) searched through MEDLINE and cited cross references, 133 were thoroughly reviewed to assess: (a) prevalence of combined alcohol use and HCV, (b) severity of liver disease (c) treatment response, and (d) mechanisms of interaction between HCV and alcohol. Data on study design, patient demographics, diagnostic tests used, and study outcomes were extracted for critical analysis.

RESULTS

Prevalence of HCV is 3-fold to 30-fold higher in alcoholics compared with the general population. Patients with HCV infection and alcohol abuse develop more severe fibrosis with higher rate of cirrhosis and hepatocellular cancer compared with nondrinkers. Increased oxidative stress seems to be the dominant mechanism for this synergism between alcohol and the HCV. Abstinence is the key to the management of liver disease due to HCV and alcohol. Data have shown that lower response rates to interferon in alcoholics with HCV infection are likely due to noncompliance.

CONCLUSIONS

Alcoholics with HCV infection have more severe liver disease compared with nondrinkers. Patients should be encouraged to enroll in rehabilitation programs so as to improve treatment adherence and response.

Alcoholic liver disease

Alcohol excess is associated with a spectrum of disease ranging from simple steatosis through steatohepatitis to cirrhosis and, in some, hepatocellular carcinoma. Alcoholic steatohepatitis itself has a variable histological picture, but a constant feature is the presence of ballooning degeneration of hepatocytes. Recent studies have emphasized the importance of apoptosis as a mechanism of cell death in this condition. It is accompanied by varying degrees of perivenular, centrilobular, and pericellular fibrosis. When severe and associated with perivenular liver cell necrosis (central sclerosing hyaline necrosis), there may be precirrhotic portal hypertension. The pattern of fibrosis may initially be diffuse with little nodule formation, but in time there is frequently the development of a micronodular cirrhosis. In approximately 15% of patients with established cirrhosis, hepatocellular carcinoma develops; several precursor lesions are now recognized which can be detected histologically. Several authors have drawn attention to additional components of the spectrum of alcoholic liver disease, including vascular changes, portal tract inflammation and fibrosis, ductular reaction, and iron overload. The morphology of alcoholic liver disease can be significantly affected by abstinence; furthermore, the clinical and morphological phenotype can be significantly influenced by the presence of comorbid conditions such as nonalcoholic fatty liver disease or viral hepatitis. Biopsy appearances can provide important prognostic information in alcoholic liver disease, and this review incorporates a proposed grading and staging schema for assessment of histological severity.

Risk factors for hepatitis C fibrosis: a prospective study of United States veterans compared with nonveterans

Chronic hepatitis C virus (HCV) infection causes cirrhosis in many infected patients; however, a better understanding of the risk factors for fibrosis progression in high HCV prevalence groups such as US veterans is needed. We wished to compare the demographic, clinical characteristics, and independent variables that influence fibrosis in US veterans vs nonveterans with chronic HCV. HCV-seropositive US veterans (n = 459) and nonveterans (n = 395) prospectively completed a detailed medical, social and occupational questionnaire. Clinical factors for progressive liver disease were compared between veterans and nonveterans and fibrosis stage assessed on liver biopsies (168 veterans and 208 nonveterans). Using polychotomous logistic regression, fibrosis was analysed as both a progressive and categorical outcome to determine independent risk factors for both patient groups. Although veterans were significantly older and had higher lifetime alcohol consumption than nonveterans, their median fibrosis scores did not differ from nonveterans. By univariate analysis, alanine aminotransferase, necroinflammatory activity (NIA), and cryoglobulin positivity were associated with fibrosis in veterans and nonveterans (P < 0.05, all comparisons), whereas steatosis was associated with fibrosis only in nonveterans (P < 0.0001). By multivariate analysis, NIA was an independent risk factor for fibrosis in both groups (P < 0.01). However, fibrosis in nonveterans was also independently associated with steatosis, significant alcohol consumption and age (P < 0.04, all comparisons). Independent risk factors for fibrosis vary among high HCV prevalence groups such as veterans when compared with nonveterans. Understanding specific patient cohort effects is important for determining independent risk factors for disease progression in chronic HCV infection.

Alcohol and hepatitis C

BACKGROUND/AIMS

Alcohol use and hepatitis C are prominent risk factors for liver injury and this review offers the current understanding of each factor's effects on liver disease.

METHODS

A Medline database search was preformed for English articles with a focus on alcohol, hepatitis C and liver disease. Article citations were also considered for further applicable articles, and the strongest studies were included in our review.

RESULTS

Up to 60% of patients with hepatitis C have a past history of alcohol use. In patients with hepatitis C, chronic alcohol consumption of more than 5 drinks/day increases the rate of liver fibrosis, risk for cirrhosis, hepatocellular carcinoma, and, possibly, death from liver disease. Numerous studies have further found that even moderate amounts of alcohol can be detrimental to hepatitis C patients. The prevalence of hepatitis C is higher in alcoholics with advanced liver disease than in alcoholics without liver disease. Also, recent alcohol use decreases the response rate to interferon treatment.

CONCLUSIONS

Hepatitis C and alcohol use are often co-occurring risk factors for liver disease, and though their interaction is not clear, it is known that heavy drinking significantly promotes liver disease progression.

[Epidemiological study of the hepatitis C virus in our population and vaccine coverage]

OBJECTIVE

Epidemiological study of patients with chronic hepatitis C and its serological status in relation to the hepatitis A (HA) and B (HB) viruses.

DESIGN

Descriptive cross-sectional study.

SETTING

Two urban health centres. Participants. 291 patients with chronic hepatitis C.

MAIN MEASUREMENTS

VARIABLES

age, sex, year and reason for diagnosis, personal histories, alcohol intake, serological status of the HA and HB viruses and HIV, and initial level of transaminases.

RESULTS

Mean age, 55 +/- 16. Sex, 52% women. Prevalence, 0.98%. Reason for diagnosis, 41% health study, 15% study of hepatic pathology, 18% study of other pathologies. Personal histories, surgical intervention, 37.5%; intravenous drug users, 21.4%; transfusion, 14%; high-risk sexual conduct, 2.4%; health material used more than once, 2.4%; family member HC positive, 1.4%; no personal history recorded, 26.5%. Alcoholism, 17.9%. Mean transaminases: AST, 79.7 +/- 100 (9-920); ALT, 114.8 +/- 160 (6-1640). HB serological status: natural immunity, 22%; chronic, 9%; vaccine immunity, 3%; negative, 44%; not recorded, 21%. HA serological status: natural immunity, 2%; vaccine immunity, 2.5%; negative, 9%; not recorded, 87%. HIV-positive: 4.5%.

CONCLUSIONS

Prevalence was below the expected level. Knowledge of serological status needs to be improved, especially for HA. The degree of vaccine coverage in these patients for HA and HB should be increased.

[Why are not all patients with chronic liver disease associated with hepatitis C virus treated?]

AIMS

To analyze the prevalence of patients with chronic liver disease associated with hepatitis C virus (HCV) not undergoing antiviral treatment and the reasons for which this treatment was not indicated.

PATIENTS AND METHODS

718 patients with HCV infection referred for therapeutic evaluation between January 1990 and January 1998. Demographic, clinical, biological and histological variables were prospectively analyzed. The patients were divided into two groups: treated and untreated.

RESULTS

393 patients were treated and in 325 patients antiviral treatment was not considered to be indicated. The most frequent reasons for not starting therapy were advanced age, the presence of decompensated cirrhosis and the patients' refusal to undergo antiviral treatment.

CONCLUSIONS

A broad subgroup of patients with chronic liver disease associated with HCV do not receive antiviral treatment. This is related with: a) patients' advanced age at diagnosis, b) diagnosis at the advanced stages of the disease, and c) patients' refusal to undergo such treatment after being informed of its potential risks and benefits.