Genetic and acquired factors that influence individual susceptibility to alcohol-associated liver disease

Gut microbiota compositional and functional fingerprint in patients with alcohol use disorder and alcohol-associated liver disease

BACKGROUND & AIMS

Alcohol use disorder (AUD) represents the most common cause of liver disease. The gut microbiota plays a critical role in the progression of alcohol-related liver damage. Aim of this study was to characterize the gut microbial composition and function in AUD patients with alcohol-associated liver disease (AALD).

METHODS

This study included 36 AUD patients (14 with cirrhosis) who were active drinkers and an equal number of matched controls. Stool microbial composition, serum levels of lipopolysaccharide, cytokines/chemokines and gut microbiota functional profile were assessed.

RESULTS

AUD patients had a decreased microbial alpha diversity as compared to controls (0.092 vs 0.130, P = .047) and a specific gut microbial signature. The reduction of Akkermansia and the increase in Bacteroides were able to identify AUD patients with an accuracy of 93.4%. Serum levels of lipopolysaccharide (4.91 vs 2.43, P = .009) and pro-inflammatory mediators (tumour necrosis factor alpha 60.85 vs 15.08, P = .001; interleukin [IL] 1beta 4.43 vs 1.72, P = .0001; monocyte chemoattractant protein 1 225.22 vs 16.43, P = .006; IL6 1.87 vs 1.23, P = .008) were significantly increased in AUD patients compared to controls and in cirrhotic patients compared to non-cirrhotic ones (IL6 3.74 vs 1.39, P = .019; IL8 57.60 vs 6.53, P = .004). The AUD-associated gut microbiota showed an increased expression of gamma-aminobutyric acid (GABA) metabolic pathways and energy metabolism.

CONCLUSIONS

AUD patients present a specific gut microbial fingerprint, associated with increased endotoxaemia, systemic inflammatory status and functional alterations that may be involved in the progression of the AALD and in the pathogenesis of AUD.

Fatty Liver Disease and Hepatocellular Carcinoma: The Pathologist's View

Chronic alcohol misuse and progressed nonalcoholic fatty liver disease (NAFLD) due to the metabolic syndrome and resulting to nonalcoholic steatohepatitis (NASH) are prime causes of hepatocellular carcinoma (HCC) in Western industrialized countries. The incidence of HCC in NASH-cirrhosis is lower than that of HCC occuring in HCV-related or alcoholic cirrhosis. Up to 20% of cases of alcohol-associated HCC may develop in pre-cirrhotic liver while HCC is also increasingly recognised in pre-cirrhotic NASH raising questions on appropriate surveillance measures for these patient populations. The recently described steatohepatitic subtype of HCC presents with higher frequency in NAFLD compared to alcoholic liver disease (ALD) patients. This review will mainly focus on histopathology and summarize current data on the epidemiology, pathogenesis, diagnosis and management of NAFLD- and ALD-related HCC.

Chronic alcohol-induced liver disease inhibits dendritic cell function

BACKGROUND/AIMS

We have compared dendritic cell (DC) function derived from the alcoholic liver disease (ALD) sensitive Long-Evans (LE) and resistant Fischer rat strains to determine if the influence of ethanol on DCs was dependent on ALD.

METHODS

The LE and Fischer rats were fed an ethanol-containing or isocaloric control liquid diet for 8 weeks and comparisons were made to LE rats injected with thioacetamide as a liver disease control. DCs were isolated from the spleen after expansion with human Fms-like tyrosine kinase receptor 3 ligand plasmid. Maturation markers CD86, CD80, CD40 and MHC-II were analysed by flow cytometry with or without lipopolysaccharide and poly I:C stimulation. Production of tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-12p40 and IL-10 cytokines and the antigen presentation ability of DCs was determined.

RESULTS

Only LE rats developed ALD characterized by liver injury, elevated alanine aminotransferase levels and steatosis; CD86 and CD40 expression was decreased in LE but not Fischer rats. Reduced TNF-α, IFN-γ, IL-12, proinflammatory and enhanced IL-10 cytokine production was found in DCs isolated from ethanol-fed LE but not Fischer rats. Allostimulatory activity was reduced in LE compared with the Fischer strain. In contrast, DCs isolated from thioacetamide-induced liver damage displayed a reduction only in IL-12p40; TNF-α, IL-10 and IFN-α production as well as antigen presenting ability remained intact compared with controls.

CONCLUSIONS

ALD sensitive LE rats exhibited characteristics of a suppressed DC phenotype that was not observed following thioacetamide-induced liver disease, which suggests an important role for ALD in altering the host cellular and humoral immune responses.

Fibrosis progression occurs in a subgroup of heavy drinkers with typical histological features

BACKGROUND

Studies using consecutive liver biopsies constitute an attractive approach to gaining insight into the pathogenesis of alcoholic liver disease.

AIM

To analyse histological factors at baseline, which are predictive of fibrosis progression and recurrence of alcoholic hepatitis.

RESULTS

A total of 193 drinkers underwent consecutive biopsies at an interval of 4 years. At baseline, 20 had normal livers, 135 steatosis, five fibrosis and 33 alcoholic hepatitis. The fibrosis score increased from 1.07 +/- 0.07 to 1.7 +/- 0.94 (P < 0.001). In multivariate analysis, only steatosis (P = 0.04), alcoholic hepatitis (P = 0.0004) and stage of fibrosis (P < 0.0001) were independent predictive factors of the fibrosis score at the second biopsy. Cirrhosis developed more frequently in patients with steatosis (11%) and alcoholic hepatitis (39%) than in others (0%, P < 0.0001). Alcoholic hepatitis recurred more frequently in patients with alcoholic hepatitis at baseline: 58% vs. 15%, P < 0.0001. In multivariate analysis, alcoholic hepatitis at the first biopsy was the only predictive factor of its recurrence (P < 0.0001).

CONCLUSIONS

In a large cohort of drinkers with consecutive biopsies, steatosis, fibrosis stage and alcoholic hepatitis at baseline were independent predictive factors of fibrosis progression. In terms of mechanisms, we propose a novel concept of multiple hits of alcoholic hepatitis occurring in the same patient.

Models of alcoholic liver disease in rodents: a critical evaluation

This article represents the proceedings of a workshop at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were J. Christian Bode and Hiroshi Fukui. The presentations were (1) Essentials and the course of the pathological spectrum of alcoholic liver disease in humans, by P. de la M. Hall; (2) Lieber-DeCarli liquid diet for alcohol-induced liver injury in rats, by C. S. Lieber and L. M. DeCarli; (3) Tsukamoto-French model of alcoholic liver injury, by S. W. French; (4) Animal models to study endotoxin-ethanol interactions, by K. O. Lindros and H. Järveläinen; and (5) Jejunoileal bypass operation in rats-A model for alcohol-induced liver injury? by Christiane Bode, Alexandr Parlesak, and J. Christian Bode.

Models of alcoholic liver disease in rodents: a critical evaluation

This article represents the proceedings of a workshop at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were J. Christian Bode and Hiroshi Fukui. The presentations were (1) Essentials and the course of the pathological spectrum of alcoholic liver disease in humans, by P. de la M. Hall; (2) Lieber-DeCarli liquid diet for alcohol-induced liver injury in rats, by C. S. Lieber and L. M. DeCarli; (3) Tsukamoto-French model of alcoholic liver injury, by S. W. French; (4) Animal models to study endotoxin-ethanol interactions, by K. O. Lindros and H. Järveläinen; and (5) Jejunoileal bypass operation in rats-A model for alcohol-induced liver injury? by Christiane Bode, Alexandr Parlesak, and J. Christian Bode.

Effects of prostaglandins on ethanol damage in primary cultured rat hepatocytes

OBJECTIVES

Several reports demonstrated that ethanol administration impairs the DNA synthesis in rat hepatocytes. Also, it has been demonstrated that prostaglandin (PG) helps prevent membrane damage by hepatotoxic chemicals. In this study, the authors examined PG's effects on the toxicity of ethanol in the primary culture of rat regenerations.

METHODS

We examined two kinds of parameters, i.e., DNA synthesis and lipid peroxidation in the primary culture of rat hepatocytes. Hepatocytes were isolated by the collagenase perfusion method. The rate of DNA synthesis was determined by pulse-labelling cultured cells with [3H]-thymidine. Incorporation of (3H)-thymidine was determined by liquid scintillation spectrophotometer. DNA content was measured by the fluorescence spectrophotometer. The lipid peroxidation was assayed with spectrophotometer.

RESULTS

The results were as follows: 1) PG family (PGA1, PGD2, PGE1, PGE2, PGG2a, PGI2 & Thromboxane B2) stimulated the DNA synthesis of hepatocytes (especially PGD2 and PGE1), 2) ethanol decreased DNA synthesis by clear dose-dependent manner, 3) the combined treatment of PGD2 or PGE1, prevents the decreasing of DNA synthesis, which was induced by ethanol, 4) in ethanol treatment, lipid peroxidation was decreased significantly, but PGD2, PGE1 and PGA1 were not affected, and 5) PGD2, PGE1 and PGA1 decreased lipid peroxidation with ethanol, significantly.

CONCLUSIONS

From these results, we concluded that PG could be useful for the treatment of degenerative liver disease and alcohol-induced liver disease in the assumption that further studies on the action mechanisms of PG will continue.

Risk factors for hepatocellular carcinoma among Japanese women

To elucidate the risk factors for hepatocellular carcinoma (HCC) among women, we made a combined analysis of the data from three case-control studies conducted in high-risk areas of Japan. A total of 120 cases and 257 controls were included in the analysis. After adjustment for the study category, age, and other potential confounders, significantly increased risks were associated with chronic hepatitis-B virus infection (odds ratio [OR] = 42.4, 95 percent confidence interval [CI] = 11.2-160.2), a past history of blood transfusion (OR = 3.7, CI = 1.8-7.5), and a history of smoking (OR = 2.2, CI = 12-4.1). In addition, women with a history of heavy drinking experienced an elevated risk of borderline significance (OR = 4.2, CI = 0.9-20.4, P = 0.07). When these ORs were compared with the corresponding estimates among males from the same case-control studies, no significant differences were observed between the two genders. Among the factors examined in this analysis, drinking and smoking habits--which are more common among Japanese men than women--may partly account for a large male-predominance in the incidence of HCC. Further studies are needed to clarify the roles that sex-hormones and hepatitis-C virus infection might play in the large gender difference of HCC occurrence.