Alcohol-associated liver disease (ALD) is an important cause of morbidity and mortality worldwide. The intestinal microbiota is involved in the development and progression of ALD; however, little is ...known about commensal fungi therein.
We studied the dynamic changes of the intestinal fungal microbiome, or mycobiome, in 66 patients with alcohol use disorder (AUD) and after 2 weeks of alcohol abstinence using internal transcribed spacer 2 (ITS2) amplicon sequencing of fecal samples.
Patients with AUD had significantly increased abundance of the genera
,
,
,
, and
, and of the species
and
compared with control subjects. Significantly improved liver health markers caspase-cleaved and intact cytokeratin 18 (CK18-M65) levels and controlled attenuation parameter (CAP) in AUD patients after 2 weeks of alcohol abstinence were associated with significantly lower abundance of the genera
,
,
,
,
, and the species
and
. This was mirrored by significantly higher specific anti-
immunoglobulin G (IgG) and M (IgM) serum levels in AUD patients in relation to control participants, and significantly decreased anti-
IgG levels in AUD subjects after 2 weeks of abstinence. The intestinal abundance of the genus
was significantly higher in AUD subjects with progressive liver disease compared with non-progressive liver disease.
In conclusion, improved liver health in AUD patients after alcohol abstinence was associated with lower intestinal abundances of
and
, and lower serum anti-
IgG levels. Intestinal fungi might serve as a therapeutic target to improve the outcome of patients in ALD.
Liver sinusoids are lined by liver sinusoidal endothelial cells (LSEC), which represent approximately 15 to 20% of the liver cells, but only 3% of the total liver volume. LSEC have unique functions, ...such as fluid filtration, blood vessel tone modulation, blood clotting, inflammatory cell recruitment, and metabolite and hormone trafficking. Different subtypes of liver endothelial cells are also known to control liver zonation and hepatocyte function. Here, we have reviewed the origin of LSEC, the different subtypes identified in the liver, as well as their renewal during homeostasis. The liver has the exceptional ability to regenerate from small remnants. The past decades have seen increasing awareness in the role of non-parenchymal cells in liver regeneration despite not being the most represented population. While a lot of knowledge has emerged, clarification is needed regarding the role of LSEC in sensing shear stress and on their participation in the inductive phase of regeneration by priming the hepatocytes and delivering mitogenic factors. It is also unclear if bone marrow-derived LSEC participate in the proliferative phase of liver regeneration. Similarly, data are scarce as to LSEC having a role in the termination phase of the regeneration process. Here, we review what is known about the interaction between LSEC and other liver cells during the different phases of liver regeneration. We next explain extended hepatectomy and small liver transplantation, which lead to “small for size syndrome” (SFSS), a lethal liver failure. SFSS is linked to endothelial denudation, necrosis, and lobular disturbance. Using the knowledge learned from partial hepatectomy studies on LSEC, we expose several techniques that are, or could be, used to avoid the “small for size syndrome” after extended hepatectomy or small liver transplantation.
Chronic alcohol consumption and alcohol-associated liver disease (ALD) represent a major public health problem worldwide. Only a minority of patients with an alcohol-use disorder (AUD) develop severe ...forms of liver disease (e.g., steatohepatitis and fibrosis) and finally progress to the more advanced stages of ALD, such as severe alcohol-associated hepatitis and decompensated cirrhosis. Emerging evidence suggests that gut barrier dysfunction is multifactorial, implicating microbiota changes, alterations in the intestinal epithelium, and immune dysfunction. This failing gut barrier ultimately allows microbial antigens, microbes, and metabolites to translocate to the liver and into systemic circulation. Subsequent activation of immune and inflammatory responses contributes to liver disease progression. Here we review the literature about the disturbance of the different host defense mechanisms linked to gut barrier dysfunction, increased microbial translocation, and impairment of liver and systemic inflammatory responses in the different stages of ALD.
Highlight ► Our data support a role for a gut–brain interaction in alcohol-dependence and open a new field of research for pharmacological interventions targeting the gut or inflammation.
The fungal microbiota plays an important role in the pathogenesis of alcohol-associated liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). In this study, we aimed to compare changes of ...the fecal fungal microbiota between patients with ALD and NAFLD and to elucidate patterns in different disease stages between the two conditions. We analyzed fungal internal transcribed spacer 2 (ITS2) sequencing using fecal samples from a cohort of 48 patients with ALD, 78 patients with NAFLD, and 34 controls. The fungal microbiota differed significantly between ALD and NAFLD. The genera
,
,
, and the species
(
),
(
),
(
) were significantly increased in patients with ALD, whereas the genera
and
were significantly increased in the NAFLD cohort. We identified the fungal signature consisting of
,
,
, and
to have the highest discriminative ability to detect ALD vs NAFLD with an area under the curve (AUC) of 0.93. When stratifying the ALD and NAFLD cohorts by fibrosis severity, the fungal signature with the highest AUC of 0.92 to distinguish ALD F0-F1 vs NAFLD F0-F1 comprised
,
,
,
, and
. For more advanced fibrosis stages (F2-F4), the fungal signature composed of
,
,
, and
achieved the highest AUC of 0.99 to differentiate ALD from NAFLD. This is the first study to identify a fungal signature to differentiate two metabolic fatty liver diseases from each other, specifically ALD from NAFLD. This might have clinical utility in unclear cases and might hence help shape treatment approaches. However, larger studies are required to validate this fungal signature in other populations of ALD and NAFLD.
Alcohol use disorder (AUD) is a chronic relapsing disease associated with malnutrition, metabolic disturbances, and gut microbiota alterations that are correlated with the severity of psychological ...symptoms. This study aims at supplementing AUD patients with prebiotic fiber during alcohol withdrawal, in order to modulate the gut microbiota composition and to evaluate its effect on gastrointestinal tolerance, metabolism, and patient's behavior. A randomized, double-blind, placebo-controlled study included 50 AUD patients assigned to inulin versus maltodextrin daily supplementation for 17 days. Biological measurements (fecal microbial 16S rDNA sequencing, serum biology), dietary intake, validated psychological questionnaires, and gastrointestinal tolerance assessment were performed before and after the intervention. Inulin significantly decreased the richness and evenness and induced changes of 8 genera (q < 0.1) including Bifidobacterium and Bacteroides. Prebiotic had minor effects on gastrointestinal symptoms and nutritional intakes compared to placebo. All patients showed an improvement in depression, anxiety, and craving scores during alcohol withdrawal regardless of the intervention group. Interestingly, only patients treated with inulin significantly improved the sociability score and had an increased serum level of brain-derived neurotrophic factor. This pilot study shows that inulin is well tolerated and modulates the gut microbiota and the social behavior in AUD patients, without further improving other psychological and biological parameters as compared to placebo. Gut2Brain study, clinicaltrial.gov: NCT03803709,
https://clinicaltrials.gov/ct2/show/NCT03803709
Alcoholic liver disease is a major medical burden. Alcohol abuse is the cause for end-stage liver disease in approximately 50% of all patients with cirrhosis. Chronic alcohol consumption is ...associated with changes in the composition of the intestinal microbiota and gut barrier dysfunction. The portal vein is the major communication route between the intestine and the liver. Increased intestinal permeability allows microbial components, bacteria, and metabolites to translocate to the liver. The liver communicates with the intestine via mediators in the systemic circulation and the biliary system. In this review, the authors describe the changes that occur in the intestinal microbiota with chronic alcohol consumption. They further review the bilateral communication between the liver and the gut, and discuss how this interaction affects the progression of alcoholic liver disease.
Alcohol-associated liver disease is a major public health concern globally. Alterations of steroid hormones and gut microbiota were both found in patients with alcohol-associated liver disease. ...However, their correlation has not been well characterized in these patients. In this study, we measured the level of 30 steroid hormones in serum and fecal samples collected from non-alcoholic controls, patients with alcohol use disorder, and patients with alcohol-associated hepatitis. The profile of serum and fecal steroid hormones was quite different in patients with alcohol-associated hepatitis from that in patients with alcohol use disorder and control subjects. Stronger alterations were observed in male patients than in females. Correlations were found not only between serum steroids and gut bacteria but also between serum steroids and gut fungi. These correlations need to be taken into consideration during the development of treatment strategies for alcohol-associated liver disease.
Excessive alcohol consumption is associated with hepatic steatosis and dysregulation of the gut microbiota in patients with alcohol use disorder (AUD). However, how gut microbiota responds when ...patients stop drinking has not been well studied. In this study, we use shotgun metagenomic sequencing to elucidate the alterations in the functional capacity of gut microbiota in patients with AUD when they stop drinking for 2-weeks. Sensitive microbial pathways to alcohol abstinence were identified in AUD patients. Further, we found the functional microbial responses to alcohol abstinence were different in AUD patients with different degree of hepatic steatosis. Our results provide insights into the link between functional alterations of the gut microbiota and steatosis associated with alcohol consumption.
The technique most frequently used to genotype HCV is quantitative RT-PCR. This technique is unable to provide an accurate genotype/subtype for many samples; we decided to develop an in-house method ...with the goal of accurately identifying the genotype of all samples. As a Belgium National Centre of reference for hepatitis, we developed in-house sequencing not only for 5'UTR and core regions starting from VERSANT LiPA amplicons but also for NS5B regions. The sequencing of VERSANT LiPA amplicons might be useful for many laboratories worldwide using the VERSANT LiPA assay to overcome undetermined results.
100 samples from Hepatitis C virus infected patients analysed by the VERSANT HCV Genotype 2.0 LiPA Assay covering frequent HCV types and subtypes were included in this study. NS5B, 5'UTR and Core home-made sequencing were then performed on these samples. The sequences obtained were compared with the HCV genomic BLAST bank.
All the samples were characterised by the VERSANT LiPA assay (8 G1a, 17 G1b, 6 G2, 11 G3, 13 G4, and 10 G6). It was not possible to discriminate between G6 and G1 by the VERSANT LiPA assay for 8 samples and 27 had an undetermined genotype. Forty-one samples were sequenced for the three regions: NS5B, 5'UTR and Core. Twenty-three samples were sequenced for two regions: 5' UTR and Core and 36 samples were sequenced only for NS5B. Of the 100 samples included, 64 samples were analysed for 5'UTR and Core sequencing and 79 samples were analysed for NS5B sequencing. The global agreement between VERSANT LiPA assay and sequencing was greater than 95%.
In this study, we describe a new, original method to confirm HCV genotypes of samples not discriminated by a commercial assay, using amplicons already obtained by the screening method, here the VERSANT LiPA assay. This method thus saves one step if a confirmation assay is needed and might be of usefulness for many laboratories worldwide performing VERSANT LiPA assay in particular.