The intestinal flora and bacterial infection in cirrhosis

Gut microbial diversity and functional characterization in people with alcohol use disorder: A case-control study

Individuals with Alcohol Use Disorder (AUD) typically have comorbid chronic health conditions, including anxiety and depression disorders, increased sleep disruption, and poor nutrition status, along with gut microbial dysbiosis. To better understand the effects of gut dysbiosis previously shown in individuals with AUD, gut microbiome and metabolome were investigated between three cohorts. Two groups of individuals with AUD included treatment-seeking newly abstinent for at least six weeks (AB: N = 10) and non-treatment-seeking currently drinking (CD: N = 9) individuals. The third group was age, gender, and BMI-matched healthy controls (HC: N = 12). Deep phenotyping during two weeks of outpatient National Institutes of Health Clinical Center visits was performed, including clinical, psychological, medical, metabolic, dietary, and experimental assessments. Alpha and beta diversity and differential microbial taxa and metabolite abundance of the gut microbiome were examined across the three groups. Metabolites derived from the lipid super-pathway were identified to be more abundant in the AB group compared to CD and HC groups. The AB individuals appeared to be most clinically different from CD and HC individuals with respect to their gut microbiome and metabolome. These findings highlight the potential long-term effects of chronic alcohol use in individuals with AUD, even during short-term abstinence.

Role of Epiregulin on Lipopolysaccharide-Induced Hepatocarcinogenesis as a Mediator via EGFR Signaling in the Cancer Microenvironment

Lipopolysaccharides (LPSs) have been reported to be important factors in promoting the progression of hepatocellular carcinoma (HCC), but the corresponding molecular mechanisms remain to be elucidated. We hypothesize that epiregulin (EREG), an epidermal growth factor (EGF) family member derived from hepatic stellate cells (HSCs) and activated by LPS stimulation, is a crucial mediator of HCC progression with epidermal growth factor receptor (EGFR) expression in the tumor microenvironment. We used a mouse xenograft model of Huh7 cells mixed with half the number of LX-2 cells, with/without intraperitoneal LPS injection, to elucidate the role of EREG in LPS-induced HCC. In the mouse model, LPS administration significantly enlarged the size of xenografted tumors and elevated the expression of EREG in tumor tissues compared with those in negative controls. Moreover, CD34 immunostaining and the gene expressions of angiogenic markers by a reverse transcription polymerase chain reaction revealed higher vascularization, with increased interleukin-8 (IL-8) expression in the tumors of the mice group treated with LPS compared to those without LPS. Our data collectively suggested that EREG plays an important role in the cancer microenvironment under the influence of LPS to increase not only the tumor cell growth and migration/invasion of EGFR-positive HCC cells but also tumor neovascularization via IL-8 signaling.

The regulatory role of bile acid microbiota in the progression of liver cirrhosis

Bile acids (BAs) are synthesized in liver tissue from cholesterol and are an important endocrine regulator and signaling molecule in the liver and intestine. It maintains BAs homeostasis, and the integrity of intestinal barrier function, and regulates enterohepatic circulation in vivo by modulating farnesoid X receptors (FXR) and membrane receptors. Cirrhosis and its associated complications can lead to changes in the composition of intestinal micro-ecosystem, resulting in dysbiosis of the intestinal microbiota. These changes may be related to the altered composition of BAs. The BAs transported to the intestinal cavity through the enterohepatic circulation are hydrolyzed and oxidized by intestinal microorganisms, resulting in changes in their physicochemical properties, which can also lead to dysbiosis of intestinal microbiota and overgrowth of pathogenic bacteria, induction of inflammation, and damage to the intestinal barrier, thus aggravating the progression of cirrhosis. In this paper, we review the discussion of BAs synthesis pathway and signal transduction, the bidirectional regulation of bile acids and intestinal microbiota, and further explore the role of reduced total bile acid concentration and dysregulated intestinal microbiota ratio in the development of cirrhosis, in order to provide a new theoretical basis for the clinical treatment of cirrhosis and its complications.

Intestinal flora plays a role in the progression of hepatitis-cirrhosis-liver cancer

The liver is a vital metabolism and detoxification organ of human body, which is involved in the biotransformation and metabolism of the organism. Hepatitis - cirrhosis - liver cancer are significant and common part of liver diseases. The pathogenesis of liver diseases is generally as followed: inflammation and other pathogenic factors cause persistent damage to the liver, leading to the activation of hepatic stellate cells (HSCs) and excessive deposition of extracellular matrix. Patients with chronic hepatitis have a high risk of developing into liver fibrosis, cirrhosis, and even life-threatening liver cancer, which poses a great threat to public health.As the first organ to come into contact with blood from the gut, the liver is profoundly affected by the intestinal flora and its metabolites, with leaky gut and flora imbalance being the triggers of the liver's pathological response. So far, no one has reviewed the role of intestinal flora in this process from the perspective of the progression of hepatitis-cirrhosis-liver cancer and this article reviews the evidence supporting the effect of intestinal flora in the progression of liver disease.

Improvement of gut microbiome and intestinal permeability following splenectomy plus pericardial devascularization in hepatitis B virus-related cirrhotic portal hypertension

The gut microbiome is an essential component of the intestinal mucosal barrier, critical in regulating intestinal permeability. Microbiome dysbiosis and intestinal permeability changes are commonly encountered conditions in patients with cirrhosis and are closely related to its development and further complications. However, alterations in the gut microbiome and intestinal permeability in chronic hepatitis B virus (HBV) patients with cirrhotic portal hypertension after undergoing a splenectomy plus pericardial devascularization (SPD) have not been investigated. This study recruited 22 patients who were measured against themselves on the study parameters before and after an SPD, along with 20 healthy controls. Methodologically, fecal samples were collected for gut microbiome analysis by 16S ribosomal DNA sequencing, and peripheral blood samples were obtained to examine the liver function and intestinal permeability. This study showed that the community structure of the gut microbiomes in patients before the SPD exhibited obvious differences from those in the healthy control group. They also exhibited a decreased bacterial community richness, increased intestinal permeability, and enhanced inflammation compared with the healthy controls. These issues were further aggravated two weeks after the SPD. There was also evidence of significantly higher abundances of Streptococcaceae, Enterobacteriaceae, and Enterococcaceae than those in the healthy control group. However, 12 months after the surgery, 12 of the 16 patient-associated genera recovered, of which 10 reached normal levels. Additionally, the microbiome diversity increased; the bacterial composition was back to a level similar to the healthy controls. Liver function, intestinal permeability, and inflammation levels all improved compared with preoperative levels. Furthermore, correlation analyses indicated that the five recovered bacterial taxa and the Shannon diversity index were correlated with several improved clinical indicators. Altogether, the improvements in the liver function and intestinal permeability in HBV-related cirrhotic patients may be related to the restoration of the gut microbiome after an SPD.

CABG in patients with liver cirrhosis: to pump or not to pump?

INTRODUCTION

Coronary artery bypass grafting in patients with established liver cirrhosis is generally associated with poor outcomes. Avoiding cardiopulmonary bypass (CPB) in these patients has not demonstrated any advantage over the use of CPB. We review the current available literature that compared the outcome of both on-pump (ONCABG) and off-pump (OPCAB) techniques in cirrhotic patients in terms of morbidity and mortality.

AREAS COVERED

A comprehensive search was conducted in the PubMed/MEDLINE and EMBASE databases in January 2021. Articles that reported outcomes of OPCAB and/or ONCABG in cirrhotic patients with no concomitant surgical procedures were included. 829 unique abstracts were retrieved with title and abstract screening completed independently by two reviewers. Two case studies and six retrospective cohort studies were included. The largest study comprised more than 98% of the total population, showing some survival benefit for OPCAB over ONCABG. However, it was population-based and did not report the severity of liver. The remaining studies reported no clear difference in outcome between the two techniques.

EXPERT OPINION

: Surgical myocardial revascularisation carries high peri-operative risk in patients with liver cirrhosis irrespective of the surgical technique. There is a lack of evidence to suggest that avoiding CPB in these patients may be beneficial.

Gut microbiome and metabolome in a non-human primate model of chronic excessive alcohol drinking

A relationship between the gut microbiome and alcohol use disorder has been suggested. Excessive alcohol use produces changes in the fecal microbiome and metabolome in both rodents and humans. Yet, these changes can be observed only in a subgroup of the studied populations, and reversal does not always occur after abstinence. We aimed to analyze fecal microbial composition and function in a translationally relevant baboon model of chronic heavy drinking that also meets binge criteria (drinking too much, too fast, and too often), i.e., alcohol ~1 g/kg and blood alcohol levels (BALs) ≥ 0.08 g/dL in a 2-hour period, daily, for years. We compared three groups of male baboons (Papio anubis): L = Long-term alcohol drinking group (12.1 years); S = Short-term alcohol drinking group (2.7 years); and C = Control group, drinking a non-alcoholic reinforcer (Tang®) (8.2 years). Fecal collection took place during 3 days of Drinking (D), followed by a short period (3 days) of Abstinence (A). Fecal microbial alpha- and beta-diversity were significantly lower in L vs. S and C (p's < 0.05). Members of the commensal families Lachnospiraceae and Prevotellaceae showed a relative decrease, whereas the opportunistic pathogen Streptococcus genus showed a relative increase in L vs. S and C (p's < 0.05). Microbiota-related metabolites of aromatic amino acids, tricarboxylic acid cycle, and pentose increased in L vs. S and C (FDR-corrected p < 0.01), with the latter two suggesting high energy metabolism and enhanced glycolysis in the gut lumen in response to alcohol. Consistent with the long-term alcohol exposure, mucosal damage and oxidative stress markers (N-acetylated amino acids, 2-hydroxybutyrate, and metabolites of the methionine cycle) increased in L vs. S and C (FDR-corrected p < 0.01). Overall, S showed few differences vs. C, possibly due to the long-term, chronic alcohol exposure needed to alter the normal gut microbiota. In the three groups, the fecal microbiome barely differed between conditions D and A, whereas the metabolome shifted in the transition from condition D to A. In conclusion, changes in the fecal microbiome and metabolome occur after significant long-term excessive drinking and are only partially affected by acute forced abstinence from alcohol. These results provide novel information on the relationship between the fecal microbiome and metabolome in a controlled experimental setting and using a unique non-human primate model of chronic excessive alcohol drinking.

Dysbiosis of Gut Microbiota Promotes Hepatocellular Carcinoma Progression by Regulating the Immune Response

Method

This study included 74 Chinese male patients with HCC. They were divided into early (n = 19), intermediate (n = 37), and terminal (n = 18) groups, referred to as Barcelona Clinic Liver Cancer stage 0+A, B, and C+D, respectively. Paired fecal and plasma samples were collected. Microbial composition and profiles were analyzed by 16S rRNA gene sequencing. The levels of gut damage marker (regenerating islet-derived protein 3α (REG3α)) and microbial translocation markers (soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP), peptidoglycan recognition proteins (PGRPs)) were determined in plasma samples of patients by ELISA. Twenty plasma cytokine and chemokines were determined by Luminex.

Results

In early, intermediate, and terminal groups, the abundance of the Bifidobacteriaceae family decreased significantly (3.52%, 1.55%, and 0.56%, respectively, P = 0.003), while the abundance of the Enterococcaceae family increased significantly (1.6%, 2.9%, and 13.4%, respectively, P = 0.022). Levels of REG3α and sCD14 were markedly elevated only in the terminal group compared with the early (P = 0.025 and P = 0.048) and intermediate groups (P = 0.023 and P = 0.046). The level of LBP significantly increased in the intermediate (P = 0.035) and terminal (P = 0.025) groups compared with the early group. The PGRP levels were elevated only in the terminal group compared with the early group (P = 0.018). The ratio of Enterococcaceae to Bifidobacteriaceae was significantly associated with the levels of REG3α, LBP, sCD14, and PGRPs. With HCC progression, increased levels of inflammatory cytokines accompanied by a T cell-immunosuppressive response and microbial translocation were observed.

Conclusion

Gut microbiota compositional and functional shift, together with elevated gut damage and microbial translocation, may promote HCC development by stimulating inflammatory response and suppressing T cell response.

Laboratory Tests in the Patient with Abdominal Pain

Abdominal pain is one of the most common presenting complaints to the emergency department (ED). More often than not, some degree of laboratory testing is used to narrow the differential diagnosis based on the patient's history and examination. Ordering practices are often guided by evidence, habit, consulting services, and institutional/regional culture. This review highlights relevant laboratory studies that may be ordered in the ED, as well as commentary on indications and diagnostic value of these tests.

Compositional distinction of gut microbiota between Han Chinese and Tibetan populations with liver cirrhosis

BACKGROUND

Liver cirrhosis (LC) is caused by numerous chronic liver diseases and its complications are associated with qualitative and quantitative alterations of the gut microbiota. Previous studies have revealed the characteristics of gut microbiota in Han Chinese patients with LC and different compositions of gut microbiota were reported between the Tibetan and Han Chinese populations. This study was designed to evaluate the unique features of the gut microbiota of Tibetans and compare the differences of gut microbiota between Tibetan and Han Chinese patients with LC.

METHODS

Thirty-six patients with liver cirrhosis and nineteen healthy volunteers, from both Tibetan and Han Chinese populations, were enrolled and fecal samples were collected for 16S rRNA gene sequencing analyses.

RESULTS

Significant differences were found in the gut microbiota of healthy volunteers and between Tibetan and Han Chinese patients with LC. In the Han Chinese patients with cirrhosis (HLC) group the relative abundances of the phylum Bacteroidetes was significantly reduced (P < 0.001), whereas in the Tibetan patients with cirrhosis (TLC) group Firmicutes and Actinobacteria were highly enriched (P = 0.01 and 0.03, respectively). At the genus level, the relative abundances of Anaerostipes (P < 0.001), Bifidobacterium (P = 0.03), and Blautia (P = 0.004) were prevalent, while Alloprevotella, Dorea, Prevotella_2, Prevotella_7 and Prevotella_9 were decreased in the TLC group compared to the HLC group (P < 0.01).

CONCLUSION

Our findings showed how the intestinal bacterial community shifted in Tibetan patients with cirrhosis.

A Double-Blind, Randomized Placebo-Controlled Trial of Probiotic Lactobacillus casei Shirota in Stable Cirrhotic Patients

Background: In cirrhosis, a pathological gut microbiome has been linked with immune dysfunction. A pilot study of probiotic Lactobacillus casei Shirota (LcS) in alcoholic cirrhosis demonstrated significant improvement in neutrophil function. This study aimed to evaluate the efficacy of LcS on neutrophil function and significant infection rates in patients with cirrhosis. Methods: 92 cirrhotic patients (Child-Pugh score ≤10) were randomized to receive LcS or placebo, three times daily for six months. Primary end-points were incidence of significant infection and neutrophil function. Secondary end-points were cytokine profile, endotoxin, bacterial DNA positivity, intestinal permeability and quality of life. Results: Rates of infection, decompensation or neutrophil function did not differ between placebo and probiotic groups. LcS significantly reduced plasma monocyte chemotactic protein-1 and, on subgroup analysis, plasma interleukin-1β (alcoholic cirrhosis), interleukin-17a and macrophage inflammatory protein-1β (non-alcoholic cirrhosis), compared with placebo. No significant differences in intestinal permeability, bacterial translocation or metabolomic profile were observed. Conclusion: LcS supplementation in patients with early cirrhosis is safe. Although no significant infections were observed in either group, LcS improved cytokine profile towards an anti-inflammatory phenotype, an effect which appears to be independent of bacterial translocation.

Serum 25-hydroxyvitamin D levels and mortality risk in patients with liver cirrhosis: a protocol for a systematic review and meta-analysis of observational studies

BACKGROUND

Liver cirrhosis represents a substantial global burden in terms of morbidity and mortality. Observational studies have reported an increased risk of death with low circulating 25-hydroxyvitamin D concentrations in such patients. Because the occurrence of inadequate vitamin D status is very common in patients with liver cirrhosis, the aim of this study is to conduct a meta-analysis of observational studies in such patients to assess whether vitamin D deficiency increases their risk of mortality.

METHODS

We will search electronic databases (MEDLINE, Embase, Web of Science, CENTRAL and Google Scholar from time of inception until now), conference proceedings and conduct manual searches to identify studies eligible for inclusion. There will be no restrictions based on publication status or language, and the meta-analysis will be reported in accordance with the MOOSE guidelines. We will employ random-effects meta-analysis to assess the relationship between vitamin D deficiency and risk of mortality. Quality of studies will be judged using the Newcastle-Ottawa scale, and between-trial heterogeneity will be evaluated by means of subgroup and sensitivity analyses.

DISCUSSION

The study will assess the effects of serum 25-hydroxyvitamin D concentrations on mortality in patients with liver cirrhosis. The results will be published in a high-quality peer-reviewed journal.

SYSTEMATIC REVIEW REGISTRATION

Prospero CRD42016052007 .

Different Sex-Based Responses of Gut Microbiota During the Development of Hepatocellular Carcinoma in Liver-Specific Tsc1-Knockout Mice

Gut microbial dysbiosis is correlated with the development of hepatocellular carcinoma (HCC). Therefore, analyzing the changing patterns in gut microbiota during HCC development, especially before HCC occurrence, is essential for the diagnosis and prevention of HCC based on gut microbial composition. However, these changing patterns in HCC are poorly understood, especially considering the sex differences in HCC incidence and mortality. Here, with an aim to determine the relationship between gut microbiota and HCC development in both sexes, and to screen potential microbial biomarkers for HCC diagnosis, we studied the changing patterns in the gut microbiota from mice of both sexes with liver-specific knockout of Tsc1 (LTsc1KO) that spontaneously developed HCC by 9–10 months of age and compared them to the patterns observed in their wide-type Tsc1^fl/fl cohorts using high-throughput sequencing. Using the LTsc1KO model, we were able to successfully exclude the continuing influence of diet on the gut microbiota. Based on gut microbial composition, the female LTsc1KO mice exhibited gut microbial disorder earlier than male LTsc1KO mice during the development of HCC. Our findings also indicated that the decrease in the relative abundance of anaerobic bacteria and the increase in the relative abundance of facultative anaerobic bacteria can be used as risk indexes of female HCC, but would be invalid for male HCC. Most of the changes in the gut bacteria were different between female and male LTsc1KO mice. In particular, the increased abundances of Allobaculum, Erysipelotrichaceae, Neisseriaceae, Sutterella, Burkholderiales, and Prevotella species have potential for use as risk indicators of female HCC, and the increased abundances of Paraprevotella, Paraprevotellaceae, and Prevotella can probably be applied as risk indicators of male HCC. These relationships between the gut microbiota and HCC discovered in the present study may serve as a platform for the identification of potential targets for the diagnosis and prevention of HCC in the future.

Splenectomy Leads to Amelioration of Altered Gut Microbiota and Metabolome in Liver Cirrhosis Patients

Dysbiosis of gut microbiota and metabolome is a frequently encountered condition in liver cirrhosis (LC) patients. The severity of liver dysfunction was found to be correlated with the degree of microbial dysbiosis. Several clinical studies have indicated liver function improvement after therapeutic splenectomy for LC-induced hypersplenism. We sought to determine whether such post-splenectomy outcome is pertinent to modulation of the abnormal gut microenvironment in LC patients. A cross-sectional study including 12 LC patients and 16 healthy volunteers was first conducted, then a before-after study in the cohort of patients was carried out before and 6 months after splenectomy. Fecal samples were collected in hospital. Temporal bacterial (n = 40) and metabolomics (n = 30) profiling was performed using 16s rRNA gene sequencing and ultra performance liquid chromatography/mass spectrometer (UPLC/MS), respectively. Our results revealed that microbial composition in patients was clearly different from that in healthy controls (HCs), evidenced by considerable taxonomic variation. Along with improved liver function (Child-Pugh score), the patients also displayed similar gut microbiota profile and predicted metagenome function to that of HCs after splenectomy. Enterobacteriaceae and Streptococcaceae, two LC-enriched families showing positive relation with Child-Pugh score, exhibited significantly decreased abundance after splenectomy. At the genus level, 11 genera were differentially abundant between patients and HCs, but 9 genera of them restituted to normal levels by certain degree after splenectomy. PICRUSt analysis showed that the relative abundance of 17 KEGG pathways was partially restored after splenectomy. Four of them were amino acid-related pathways: lysine degradation, tryptophan degradation, amino acid metabolism, and protein digestion and absorption. These findings were supported by metabonomics results which showed that relative abundance of amino acid and corresponding catabolites changed toward normal. In addition to the variations in the relative abundances of bacteria and metabolites, the correlation between them also altered in patients after splenectomy. Dysbiosis in gut microbiome and related metabolism of LC patients was partially corrected after splenectomy. Whether the improved gut microenvironment could prevent LC-related complications and delay the progress of LC is a propitious objective for future study.

TRIAL REGISTRATION

ChiCTR-OOB-15007409. Registered November 15, 2015.

Alterations of oral microbiota distinguish children with autism spectrum disorders from healthy controls

Altered gut microbiota is associated with autism spectrum disorders (ASD), a group of complex, fast growing but difficult-to-diagnose neurodevelopmental disorders worldwide. However, the role of the oral microbiota in ASD remains unexplored. Via high-throughput sequencing of 111 oral samples in 32 children with ASD and 27 healthy controls, we demonstrated that the salivary and dental microbiota of ASD patients were highly distinct from those of healthy individuals. Lower bacterial diversity was observed in ASD children compared to controls, especially in dental samples. Also, principal coordinate analysis revealed divergences between ASD patients and controls. Moreover, pathogens such as Haemophilus in saliva and Streptococcus in plaques showed significantly higher abundance in ASD patients, whereas commensals such as Prevotella, Selenomonas, Actinomyces, Porphyromonas, and Fusobacterium were reduced. Specifically, an overt depletion of Prevotellaceae co-occurrence network in ASD patients was obtained in dental plaques. The distinguishable bacteria were also correlated with clinical indices, reflecting disease severity and the oral health status (i.e. dental caries). Finally, diagnostic models based on key microbes were constructed, with 96.3% accuracy in saliva. Taken together, this study characterized the habitat-specific profile of the oral microbiota in ASD patients, which might help develop novel strategies for the diagnosis of ASD.

Characteristics of fecal microbial communities in patients with non-anastomotic biliary strictures after liver transplantation

AIM

To explore the possible relationship between fecal microbial communities and non-anastomotic stricture (NAS) after liver transplantation (LT).

METHODS

A total of 30 subjects including 10 patients with NAS, 10 patients with no complications after LT, and 10 non-LT healthy individuals were enrolled. Fecal microbial communities were assessed by the 16S rRNA gene sequencing technology.

RESULTS

Different from the uncomplicated and healthy groups, unbalanced fecal bacterium ratio existed in patients with NAS after LT. The results showed that NAS patients were associated with a decrease of Firmicutes and Bacteroidetes and an increase of Proteobacteria at the phylum level, with the proportion-ratio imbalance between potential pathogenic families including Enterococcaceae, Streptococcaceae, Enterobacteriaceae, Pseudomonadaceae and dominant families including Bacteroidaceae.

CONCLUSION

The compositional shifts of the increase of potential pathogenic bacteria as well as the decrease of dominant bacteria might contribute to the incidence of NAS.

Nutritional Therapy in Liver Transplantation

Protein-energy malnourishment is commonly encountered in patients with end-stage liver disease who undergo liver transplantation. Malnutrition may further increase morbidity, mortality and costs in the post-transplantation setting. The importance of carefully assessing the nutritional status during the work-up of patients who are candidates for liver replacement is widely recognized. The metabolic abnormalities induced by liver failure render the conventional assessment of nutritional status to be challenging. Preoperative loss of skeletal muscle mass, namely, sarcopenia, has a significant detrimental impact on post-transplant outcomes. It is essential to provide sufficient nutritional support during all phases of liver transplantation. Oral nutrition is preferred, but tube enteral nutrition may be required to provide the needed energy intake. Herein, the latest currently employed perioperative nutritional interventions in liver transplant recipients are thoroughly illustrated including synbiotics, micronutrients, branched-chain amino acid supplementation, immunonutrition formulas, fluid and electrolyte balance, the offering of nocturnal meals, dietary counselling, exercise and rehabilitation.

The gut-liver axis: impact of a mouse model of small-bowel bacterial overgrowth

BACKGROUND

The mechanisms by which intestinal bacteria impact liver diseases remain poorly understood. The aim of this study was to develop a mouse model of small-bowel bacterial overgrowth and to determine its impact on hepatobiliary injury.

MATERIALS AND METHODS

A jejunal self-filling blind loop (SFBL) was created in C57BL/6 mice. Three weeks after surgery, the mice were euthanized, and bacterial cultures of luminal content of the loop and extraintestinal tissues were performed. Liver and jejunum were collected for histological grading of inflammation and injury. Serum liver biochemistry assays were performed. Hepatobiliary transporter mRNA expression in liver was measured by quantitative real-time polymerase chain reaction. Bile and blood were collected for measurement of total bile acids, phospholipid, and cholesterol. Mice undergoing jejunal transection and reanastomosis and laparotomy only served as control groups.

RESULTS

SFBL induced a dramatic increase in intraluminal bacterial counts, mesenteric lymph node bacterial translocation, and evidence of jejunal and hepatobiliary injury. Significant reductions in hepatic expression of hepatobiliary transporters involved in biliary canalicular export and basolateral uptake were observed in SFBL mice. SFBL resulted in a significant increase in biliary total bile acid concentration, decreases in bile phospholipid and cholesterol output, and an increase in the bile acid/phospholipid ratio.

CONCLUSIONS

We have developed a reproducible mouse model of small-bowel bacterial overgrowth with evidence of liver inflammation, altered hepatobiliary transporter expression, and alterations in bile composition. This model may help to elucidate the mechanisms by which gut-derived bacterial factors impact the liver and contribute to the exacerbation of liver diseases and biliary injury.

Non-selective β-blockers in advanced cirrhosis: a critical review of the effects on overall survival and renal function

Introduction

Non-selective β-blockers (NSBBs) are widely prescribed in patients with cirrhosis for primary and secondary prophylaxis of bleeding oesophageal varices. Furthermore, it has been suggested that the clinical benefits of NSBBs may extend beyond their haemodynamic effects. Recently, a potentially harmful effect has been described in patients with refractory ascites or spontaneous bacterial peritonitis.

Methodology

A comprehensive literature search on β-blockers and cirrhosis survival using the electronic databases PubMed/MEDLINE, AMED, CINAHL and the Cochrane Central Register of Controlled Trials. Full-text manuscripts published over more than 35 years, from 1980 to April 2016 were reviewed for relevance and reference lists were cross-checked for additional pertinent studies regarding potential NSBB effects, especially focused on those concerned with survival and/or acute kidney injury (AKI).

Discussion

The proposed review will be able to provide valuable evidence to help decision making in the use of NSBB for the treatment of advanced cirrhosis and highlights some limitations in existing evidence to direct future research.

The Beneficial Effect of Beta-Blockers in Patients With Cirrhosis, Portal Hypertension and Ascites

BACKGROUND

Patients with cirrhosis and portal hypertensive complications have reduced survival. As such, it has been suggested that nonselective beta-blocker therapy in patients with advanced ascites is harmful. The aim of this study was, therefore, to determine the risk of mortality in patients with cirrhosis and ascites taking nonselective beta-blocker therapy for the prevention of variceal hemorrhage.

MATERIALS AND METHODS

This study was a retrospective analysis of 2,419 patients with cirrhosis and portal hypertension admitted to Parkland Memorial Hospital (a university-affiliated county teaching hospital) from 2003-2010. Patients were subdivided into those with varices only, ascites only and those with both varices and ascites. The primary outcome measure for this study was all-cause in-hospital mortality.

RESULTS

Overall, 68 of 1,039 (6.5%) patients taking beta-blockers died during their hospitalization, while 223 of 1,380 (16.2%) patients not taking beta-blockers died (P < 0.001). Beta-blocker use was also assessed in specific cohorts; mortality was 21.1% in patients with severe ascites with varices who were not taking beta-blockers compared with 8.9% in patients who were taking beta-blockers (P = 0.05). Overall, fewer patients taking beta-blockers died compared with those not taking beta-blockers in patients with varices only (6.4% versus 12.1%) and those with ascites with or without varices (6.6% versus 18.1%) (P < 0.001).

CONCLUSIONS

Mortality was lower in patients with cirrhosis and portal hypertension taking nonselective beta-blockers than in those not taking beta-blockers. The use of nonselective beta-blockers provided a significant survival benefit in patients with all grades of ascites, including those with severe ascites.

Liver cirrhosis as a real risk factor for necrotising fasciitis: a three-year population-based follow-up study

INTRODUCTION

Necrotising fasciitis (NF) is often found in patients with diabetes mellitus, chronic renal failure, alcoholism, malignancy or liver cirrhosis. However, it remains unknown whether liver cirrhosis is an independent risk factor for the occurrence of NF. This study aimed to determine whether liver cirrhosis is an independent risk factor for the occurrence of NF, and to identify the relationship between severity of liver cirrhosis and occurrence of NF.

METHODS

The National Health Insurance Research Database, maintained by Taiwan's National Health Insurance programme, was retrospectively analysed, and the hospitalisation data of 40,802 cirrhotic patients and 40,865 randomly selected, age‑ and gender‑matched non‑cirrhotic control patients was collected. The medical records of all patients were individually followed for a three‑year period from the patients' first hospitalisation in 2004.

RESULTS

During the three‑year follow‑up period, there were 299 (0.7%) cirrhotic patients with NF and 160 (0.4%) non‑cirrhotic patients with NF. Cox regression analysis showed that liver cirrhosis was a risk factor for the occurrence of NF during the study period (hazard ratio 1.982; p < 0.001). Among cirrhotic patients, those with complicated liver cirrhosis had a higher risk for the occurrence of NF than patients with non‑complicated liver cirrhosis (hazard ratio 1.320; p = 0.028).

CONCLUSION

Cirrhotic patients had a higher risk for the occurrence of NF than non‑cirrhotic patients, and the risk for NF was especially high among patients with complicated liver cirrhosis.

Oral administration of Saccharomyces boulardii ameliorates carbon tetrachloride-induced liver fibrosis in rats via reducing intestinal permeability and modulating gut microbial composition

To investigate the effects of orally administrated Saccharomyces boulardii (S. boulardii) on the progress of carbon tetrachloride (CCl4)-induced liver fibrosis, 34 male Wistar rats were randomly divided into four experimental groups including the control group (n = 8), the cirrhotic group (n = 10), the preventive group (n = 8), and the treatment group (n = 8). Results showed that the liver expression levels of collagen, type I, alpha 1 (Col1A1), alpha smooth muscle actin (αSMA), transforming growth factor beta (TGF-β) and the serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) increased significantly in cirrhotic rats compared with control and decreased by S. boulardii administration. Treatment of S. boulardii also attenuated the increased endotoxin levels and pro-inflammatory cytokines in CCl4-treated rats. And, these were associated with the changes of intestinal permeability and fecal microbial composition. Our study suggested that oral administration of S. boulardii can promote the liver function of CCl4-treated rats, and the preventive treatment of this probiotic yeast may decelerate the progress of liver fibrosis.

Metagenomics: A New Way to Illustrate the Crosstalk between Infectious Diseases and Host Microbiome

Microbes have co-evolved with human beings for millions of years. They play a very important role in maintaining the health of the host. With the advancement in next generation sequencing technology, the microbiome profiling in the host can be obtained under different circumstances. This review focuses on the current knowledge of the alteration of complex microbial communities upon the infection of different pathogens, such as human immunodeficiency virus, hepatitis B virus, influenza virus, and Mycobacterium tuberculosis, at different body sites. It is believed that the increased understanding of the correlation between infectious disease and the alteration of the microbiome can contribute to better management of disease progression in the future. However, future studies may need to be more integrative so as to establish the exact causality of diseases by analyzing the correlation between microorganisms within the human host and the pathogenesis of infectious diseases.

Clinical and pathophysiological consequences of alterations in the microbiome in cirrhosis

Cirrhosis is a major cause of mortality worldwide. Exponential rises in prevalence have been observed secondary to increases in obesity and alcohol consumption. Multiple lines of evidence implicate gut-derived bacteria and bacterial ligands as a central driver of pathogenesis. Recent developments in culture-independent techniques have facilitated a more accurate description of microbiome composition in cirrhosis and led to the description of measures of dysbiosis shown to be associated with disease. More importantly, metagenomic studies are adding to an understanding of the functional contribution of the microbiota and may prove to be a more clinically relevant biomarker than phylogenetic studies. Much like other dysbiotic states such as inflammatory bowel disease, the microbiota in cirrhosis is characterized by a low microbial and genetic diversity. Therapeutic strategies to diminish this process are currently limited to selective intestinal decontamination with antibiotics. This review summarizes the available data and develops a framework for the use of current and future treatment strategies to diminish the consequences of dysbiosis in cirrhosis. Interventional strategies to bind bacterial products in the gut lumen and blood, and modulate the magnitude of host sensing mechanisms remain an unmet clinical need. A greater understanding of the host-microbiota interaction in cirrhosis is of key importance to inform future interventional strategies to diminish the currently escalating burden of the disease.

The administration of probiotics and synbiotics in immune compromised adults: is it safe?

This study aimed to systematically evaluate safety of probiotics and synbiotics in immune compromised adults (≥18 years). Safety was analysed using the Common Terminology Clinical Adverse Events (CTCAE version 4.0) classification, thereby providing an update on previous reports using the most recent available clinical data (2008-2013). Safety aspects are represented and related to number of participants per probiotic strain/culture, study duration, dosage, clinical condition and selected afflictions. Analysis of 57 clinical studies indicates that probiotic and/or synbiotic administration in immune compromised adults is safe with regard to the current evaluated probiotic strains, dosages and duration. Individuals were considered immune compromised if HIV-infected, critically ill, underwent surgery or had an organ- or an autoimmune disease. There were no major safety concerns in the study, as none of the serious adverse events (AE)s were related, or suspected to be related, to the probiotic or synbiotic product and the study products were well tolerated. Overall, AEs occurred less frequent in immune compromised subjects receiving probiotics and/or synbiotics compared to the control group. In addition, the results demonstrated a flaw in precise reporting and classification of AE in most studies. Furthermore, generalisability of conclusions are greatly limited by the inconsistent, imprecise and potentially incomplete reporting as well as the variation in probiotic strains, dosages, administration regimes, study populations and reported outcomes. We argue that standardised reporting on adverse events (CTCAE) in 'food' studies should be obligatory, thereby improving reliability of data and re-enforcing the safety profile of probiotics.

Outcome of hepatectomy for hepatocellular carcinoma in elderly patients with portal hypertension

The outcome of liver resection (LR) for elderly hepatocellular carcinoma (HCC) patients with portal hypertension (PHT) who may be excluded as liver transplantation candidates has not been fully evaluated. One hundred ninety-five patients who underwent initial curative LR for HCC with PHT were divided into 2 groups: age <70 years (n = 131) and age ≥70 years (n = 64). Clinicopathologic data and postoperative complications were compared. Preoperative characteristics and postoperative complications were similar in both groups. However, in-hospital mortality was significantly more frequent in elderly than in younger patients (11% versus 1%, P = 0.002). No significant intergroup differences were observed in the 5-year disease-free survival rate or recurrence rate (19.7% versus 17.2%; P = 0.338, 63% versus 56%; P = 0.339). Although LR for elderly HCC patients with PHT can be performed with curative intent and gives results comparable with those in younger patients, it is associated with higher in-hospital mortality.

The INCA trial (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites): study protocol for a randomized controlled trial

BACKGROUND

Patients with liver cirrhosis have a highly elevated risk of developing bacterial infections that significantly decrease survival rates. One of the most relevant infections is spontaneous bacterial peritonitis (SBP). Recently, NOD2 germline variants were found to be potential predictors of the development of infectious complications and mortality in patients with cirrhosis. The aim of the INCA (Impact of NOD2 genotype-guided antibiotic prevention on survival in patients with liver Cirrhosis and Ascites) trial is to investigate whether survival of this genetically defined high-risk group of patients with cirrhosis defined by the presence of NOD2 variants is improved by primary antibiotic prophylaxis of SBP.

METHODS/DESIGN

The INCA trial is a double-blind, placebo-controlled clinical trial with two parallel treatment arms (arm 1: norfloxacin 400 mg once daily; arm 2: placebo once daily; 12-month treatment and observational period). Balanced randomization of 186 eligible patients with stratification for the protein content of the ascites (<15 versus ≥ 15 g/L) and the study site is planned. In this multicenter national study, patients are recruited in at least 13 centers throughout Germany. The key inclusion criterion is the presence of a NOD2 risk variant in patients with decompensated liver cirrhosis. The most important exclusion criteria are current SBP or previous history of SBP and any long-term antibiotic prophylaxis. The primary endpoint is overall survival after 12 months of treatment. Secondary objectives are to evaluate whether the frequencies of SBP and other clinically relevant infections necessitating antibiotic treatment, as well as the total duration of unplanned hospitalization due to cirrhosis, differ in both study arms. Recruitment started in February 2014.

DISCUSSION

Preventive strategies are required to avoid life-threatening infections in patients with liver cirrhosis, but unselected use of antibiotics can trigger resistant bacteria and worsen outcome. Thus, individualized approaches that direct intervention only to patients with the highest risk are urgently needed. This trial meets this need by suggesting stratified prevention based on genetic risk assessment. To our knowledge, the INCA trial is first in the field of hepatology aimed at rapidly transferring and validating information on individual genetic risk into clinical decision algorithms.

TRIAL REGISTRATIONS

German Clinical Trials Register DRKS00005616 . Registered 22 January 2014. EU Clinical Trials Register EudraCT 2013-001626-26 . Registered 26 January 2015.

Oral probiotic VSL#3 attenuates the circulatory disturbances of patients with cirrhosis and ascites

BACKGROUND & AIMS

The modulation of gut flora constitutes a therapeutic tool in patients with liver disease, but some of its modalities require further investigation. Here, we evaluated the effects of probiotics on the hepatic and systemic haemodynamic alterations of advanced liver disease.

METHODS

Seventeen patients with cirrhosis and ascites were prospectively included, five of whom abandoned this study prematurely. Hepatic and systemic haemodynamic evaluations were performed at baseline and after 6 weeks of receiving an oral VSL#3 probiotic preparation. Peripheral blood analyses included the evaluation of cytokines (TNF-alpha, IL-1beta, IL-6), bacterial translocation [bacterial DNA and lipopolysaccharide-binding protein (LBP)] and nitric oxide end-products (NOx).

RESULTS

In 12 patients completing this study, the oral administration of VSL#3 resulted in reductions of the hepatic venous pressure gradient (HVPG, P < 0.001), cardiac index and heart rate (both P < 0.01) and in increases of the systemic vascular resistance (P < 0.05) and mean arterial pressure (P = 0.06). HVPG decreased at least 10% from baseline in eight patients (67%). Serum sodium increased in most patients (P < 0.01). All these changes were unrelated to the detection of bacterial DNA or to the levels of LBP, pro-inflammatory cytokines or NOx. No significant adverse effects were observed.

CONCLUSION

Administration of the probiotic mixture VSL#3 improved the hepatic and systemic haemodynamics and serum sodium levels in patients with cirrhosis. Our results identify major effects of probiotics in liver disease and provide the rationale for assessing their therapeutic potential against the progression of portal hypertension and its complications in future clinical trials.

The role of the gut microbiome in the development and progression of liver cirrhosis and hepatocellular carcinoma

Liver cirrhosis and hepatocellular carcinoma (HCC) represent the endstage of most chronic liver diseases and are a major global health burden. It has been consistently shown that both liver cirrhosis and HCC are triggered by inflammatory processes, but the molecular mechanisms linking chronic hepatitis with cirrhosis and HCC are only poorly understood. Recent studies suggested that the intestinal microflora as a main source of portal-vein LPS might play a critical role in this process. Here we summarize the available literature on the role of the gut microbiome in hepatofibrogenesis and -carcinogenesis. Such knowledge might help to develop novel, innovative strategies for the prevention and therapy of liver disease.

Usefulness of a new inflammation-based scoring system for prognostication of patients with hepatocellular carcinoma after hepatectomy

BACKGROUND

We investigated whether a preoperative scoring system (the "CRP-AFP Score [CAS]") based on the serum levels of C-reactive protein and alpha-fetoprotein would predict outcome in patients undergoing hepatectomy for hepatocellular carcinoma.

METHODS

The CAS was defined as follows: patients with an elevated level of both C-reactive protein (>.3 mg/dL) and alpha-fetoprotein (>20 ng/mL) were assigned a score of 2, and patients showing one or none of these abnormalities were assigned a score of 1 or 0, respectively.

RESULTS

A total of 349 patients were identified. Pathologic findings, in terms of tumor size, histologic grade, vascular invasion, intrahepatic metastasis, and recurrence rate, worsened as the CAS increased. CAS 2 patients had a poorer 5-year overall survival than CAS 0 or 1 patients (32.2% vs 59.7% vs 49.2%, respectively; P < .001).

CONCLUSIONS

The CAS is an informative scoring system that can predict outcome in patients with hepatocellular carcinoma after hepatectomy.

Laboratory diagnostics of spontaneous bacterial peritonitis

The term peritonitis indicates an inflammatory process involving the peritoneum that is most frequently infectious in nature. Primary or spontaneous bacterial peritonitis (SBP) typically occurs when a bacterial infection spreads to the peritoneum across the gut wall or mesenteric lymphatics or, less frequently, from hematogenous transmission in combination with impaired immune system and in absence of an identified intra-abdominal source of infection or malignancy. The clinical presentation of SBP is variable. The condition may manifest as a relatively insidious colonization, without signs and symptoms, or may suddenly occur as a septic syndrome. Laboratory diagnostics play a pivotal role for timely and appropriate management of patients with bacterial peritonitis. It is now clearly established that polymorphonuclear leukocyte (PMN) in peritoneal fluid is the mainstay for the diagnosis, whereas the role of additional biochemical tests is rather controversial. Recent evidence also suggests that automatic cell counting in peritoneal fluid may be a reliable approach for early screening of patients. According to available clinical and laboratory data, we have developed a tentative algorithm for efficient diagnosis of SBP, which is based on a reasonable integration between optimization of human/economical resources and gradually increasing use of invasive and expensive testing. The proposed strategy entails, in sequential steps, serum procalcitonin testing, automated cell count in peritoneal fluid, manual cell count in peritoneal fluid, peritoneal fluid culture and bacterial DNA testing in peritoneal fluid.

Variceal rebleeding: use of drug therapy and endoscopic band ligation

Patients surviving a variceal bleed are at high risk of re-bleeding with a mortality of 25-50% during a 1-2 year follow-up. Several studies and meta-analyses have demonstrated reduced rates of oesophageal variceal rebleeding with the use of β-blockers. However, their use can be limited by contraindications or intolerance to therapy. Other trials have shown that addition of nitrates may improve the efficacy of β-blockers in prevention of variceal re-bleeding. Endoscopic variceal band ligation (VBL) has been shown in meta-analyses to decrease the rates of rebleeding and mortality compared with endoscopic sclerotherapy. Studies comparing combined drug therapy with VBL have shown similar rebleeding rates although there is a suggestion that survival may be higher in those given drug therapy. Recent data suggest that combined VBL and drug therapy reduces the risk of rebleeding from oesophageal varices compared with either therapy alone; however there appears to be no reduction in overall mortality.

Perioperative nutritional therapy in liver transplantation

Protein-energy malnutrition is frequently seen in patients with end-stage liver disease who undergo liver transplantation. This causes a deterioration of the patients' clinical condition and affects their post-transplantation survival. Accurate assessment of the nutritional status and adequate intervention are prerequisites for perioperative nutritional treatment. However, the metabolic abnormalities induced by liver failure make the traditional assessment of the nutritional status difficult. The methods that were recently developed for accurately assessing the nutritional status by body bioelectrical impedance may be implemented in pre-transplant management. Because preoperative malnutrition and the loss of skeletal muscle mass, called sarcopenia, have a significant negative impact on the post-transplantation outcome, it is essential to provide adequate nutritional support during all phases of liver transplantation. Oral nutrition is preferred, but tube enteral nutrition may be required to provide the necessary caloric intake. We herein discuss both bioelectrical impedance and the latest findings in the current perioperative nutritional interventions in liver transplant patients regarding synbiotics, micronutrients, branched-chain amino acid supplementation, the use of immune system modulating formulas, the fluid balance and the offering of nocturnal meals.

Activated intestinal macrophages in patients with cirrhosis release NO and IL-6 that may disrupt intestinal barrier function

BACKGROUND & AIMS

Bacterial infections commonly occur in decompensated cirrhosis resulting from bacterial translocation from the intestine. We studied the role of intestinal macrophages and the epithelial barrier in cirrhosis.

METHODS

Forty-four patients with NASH/ASH cirrhosis (decompensated n=29, compensated n=15) and nineteen controls undergoing endoscopy were recruited. Serum was obtained and LPS and LBP levels determined. Intestinal macrophages were characterized by flow cytometry, immunohistochemistry, and nitric oxide (NO) production measured in supernatant of cultured duodenal samples. Quantitative RT-PCR was performed on duodenal biopsies assessing 84 inflammatory genes. Protein levels of cytokines/chemokines were assessed in serum and supernatant. The duodenal wall was assessed by electron microscopy, tight junction protein expression determined by RT-PCR, immunohistochemistry, and Western blot and, functional analysis performed by transepithelial resistance measurement and permeability studies.

RESULTS

Increased plasma LPS, LBP levels and higher numbers of duodenal CD33(+)/CD14(+)/Trem-1(+) macrophages, synthesizing iNOS and secreting NO were present in decompensated cirrhosis. Upregulation of IL-8, CCL2, CCL13 at the transcriptional level, and increased IL-8, and IL-6 were detected in supernatant and serum in cirrhosis. IL-6 and IL-8 co-localised with iNOS(+) and CD68(+), but not with CD11c(+) cells. Electron microscopy demonstrated an intact epithelial barrier. Increased Claudin-2 was detected by Western blot and immunohistochemistry, while decreased transepithelial resistance and increased duodenal permeability were detected in decompensated cirrhosis.

CONCLUSIONS

Our study shows the presence of activated CD14(+)Trem-1(+)iNOS(+) intestinal macrophages, releasing IL-6, NO, and increased intestinal permeability in patients with cirrhosis, suggesting that these cells may produce factors capable of enhancing permeability to bacterial products.

Probiotic as a novel treatment strategy against liver disease

CONTEXT

A symbiotic relationship between the liver and intestinal tract enables the healthy status of both organs. Microflora resident in intestinal lumen plays a significant role in hepatocytes function. Alterations to the type and amount of microorganisms that live in the intestinal tract can result in serious and harmful liver dysfunctions such as cirrhosis, nonalcoholic fatty liver disease, alcoholic liver disease, and hepatic encephalopathy. An increased number of pathogens, especially enterobacteriaceae, enterococci, and streptococci species causes the elevation of intestinal permeability and bacterial translocation. The presence of high levels of lipopolysaccharide (LPS) and bacterial substances in the blood result in a portal hypertension and ensuing hepatocytes damage. Several methods including the usage of antibiotics, prebiotics, and probiotics can be used to prevent the overgrowth of pathogens. Compared to prebiotic and antibiotic therapy, probiotics strains are a safer and less expensive therapy. Probiotics are "live microorganisms (according to the FAO/WHO) which when administered in adequate amounts confer a health benefit on the host".

EVIDENCE ACQUISITIONS

Data from numerous preclinical and clinical trials allows for control of the flora bacteria quantity, decreases in compounds derived from bacteria, and lowers proinflammatory production such as TNF-α, IL-6 and IFN-γ via down-regulation of the nuclear factor kappa B (NF-κ B).

RESULTS

On the other hand, probiotic can reduce the urease activity of bacterial microflora. Furthermore, probiotic decreases fecal pH value and reduces ammonia adsorption. In addition, the serum level of liver enzymes and other substances synthesized by the liver are modulated subsequent to probiotic consumption.

CONCLUSIONS

According to our knowledge, Probiotic therapy as a safe, inexpensive and a noninvasive strategy can reduce pathophysiological symptoms and improve different types of liver diseases without side effects.

Profound impact of gut homeostasis on chemically-induced pro-tumorigenic inflammation and hepatocarcinogenesis in rats

BACKGROUND & AIMS

Due to its anatomic connection, the liver is constantly exposed to gut-derived bacterial products or metabolites. Disruption of gut homeostasis is associated with many human diseases. The aim of this study was to determine the role of gut homeostasis in initiation and progression of hepatocellular carcinoma (HCC).

METHODS

Disruption of intestinal homeostasis by penicillin or dextran sulfate sodium (DSS) and its restoration by probiotics were applied in a diethylnitrosamine (DEN) model of rat hepatocarcinogenesis.

RESULTS

Patients with liver cirrhosis and HCC had significantly increased serum endotoxin levels. Chronic DEN treatment of rats was associated with an imbalance of subpopulations of the gut microflora including a significant suppression of Lactobacillus species, Bifidobacterium species and Enterococcus species as well as intestinal inflammation. Induction of enteric dysbacteriosis or intestinal inflammation by penicillin or DSS, respectively, significantly promoted tumor formation. Administration of probiotics dramatically mitigated enteric dysbacteriosis, ameliorated intestinal inflammation, and most importantly, decreased liver tumor growth and multiplicity. Interestingly, probiotics not only inhibited the translocation of endotoxin, which bears pathogen-associated molecular patterns (PAMPs) but also the activation of damage-associated molecular patterns (DAMPs) such as high-mobility group box 1 (HMGB1). As a result, the production of pro- and anti-inflammatory cytokines was skewed in favor of a reduced tumorigenic inflammation in the liver.

CONCLUSIONS

The data highlights the importance of gut homeostasis in the pathogenesis of HCC. Modulation of the gut microbiota by probiotics may represent a new avenue for therapeutic intervention to treat or prevent HCC development.

Interaction of Hepatitis C virus proteins with pattern recognition receptors

Hepatitis C virus (HCV) is an important human pathogen that causes acute and chronic hepatitis, cirrhosis and hepatocellular carcinoma worldwide. This positive stranded RNA virus is extremely efficient in establishing persistent infection by escaping immune detection or hindering the host immune responses. Recent studies have discovered two important signaling pathways that activate the host innate immunity against viral infection. One of these pathways utilizes members of Toll-like receptor (TLR) family and the other uses the RNA helicase retinoic acid inducible gene I (RIG-I) as the receptors for intracellular viral double stranded RNA (dsRNA), and activation of transcription factors. In this review article, we summarize the interaction of HCV proteins with various host receptors/sensors through one of these two pathways or both, and how they exploit these interactions to escape from host defense mechanisms. For this purpose, we searched data from Pubmed and Google Scholar. We found that three HCV proteins; Core (C), non structural 3/4 A (NS3/4A) and non structural 5A (NS5A) have direct interactions with these two pathways. Core protein only in the monomeric form stimulates TLR2 pathway assisting the virus to evade from the innate immune system. NS3/4A disrupts TLR3 and RIG-1 signaling pathways by cleaving Toll/IL-1 receptor domain-containing adapter inducing IFN-beta (TRIF) and Cardif, the two important adapter proteins of these signaling cascades respectively, thus halting the defense against HCV. NS5A downmodulates the expressions of NKG2D on natural killer cells (NK cells) via TLR4 pathway and impairs the functional ability of these cells. TLRs and RIG-1 pathways have a central role in innate immunity and despite their opposing natures to HCV proteins, when exploited together, HCV as an ever developing virus against host immunity is able to accumulate these mechanisms for near unbeatable survival.

Intestinal bacterial translocation in rats with cirrhosis is related to compromised Paneth cell antimicrobial host defense

Liver cirrhosis is associated with bacterial translocation (BT) and endotoxemia. Most translocating bacteria belong to the common intestinal microbiota, suggesting a breakdown of intestinal barrier function. We hypothesized that diminished mucosal antimicrobial host defense could predispose to BT. Two rodent models of portal hypertension with increased BT were used, CCl(4)-induced ascitic cirrhosis and 2-day portal vein-ligated (PVL) animals. BT was assessed by standard microbiological techniques on mesenteric lymph nodes. Total RNA was isolated systematically throughout the intestinal tract, and expression of Paneth cell α-cryptdins and β-defensins was determined by real-time quantitative polymerase chain reaction (qPCR). To determine functional consequences, mucosal antimicrobial activity was assessed with a fluorescence-activated cell sorting assay. BT was detectable in 40% of rats with cirrhosis. Compared with the group without BT, these animals exhibited diminished intestinal Paneth cell α-cryptdin 5 and 7 expression. In contrast, PVL was associated with BT in all animals but did not affect antimicrobial peptides. The decrease in Paneth cell antimicrobials was most pronounced in the ileum and the coecum. Other antimicrobials showed no changes or even an induction in the case of BT at different sites. Antimicrobial activity toward different commensal strains was reduced, especially in the distal ileum and the cecum in experimental cirrhosis with BT (excluding PVL).

CONCLUSION

Compromised Paneth cell antimicrobial host defense seems to predispose to BT in experimental cirrhosis. Understanding this liver-gut axis including the underlying mechanisms could help us to find new treatment avenues.

Intestinal decontamination inhibits TLR4 dependent fibronectin-mediated cross-talk between stellate cells and endothelial cells in liver fibrosis in mice

BACKGROUND & AIMS

Liver fibrosis is associated with angiogenesis and leads to portal hypertension. Certain antibiotics reduce complications of liver failure in humans, however, the effects of antibiotics on the pathologic alterations of the disease are not fully understood. The aim of this study was to test whether the non-absorbable antibiotic rifaximin could attenuate fibrosis progression and portal hypertension in vivo, and explore potential mechanisms in vitro.

METHODS

The effect of rifaximin on portal pressure, fibrosis, and angiogenesis was examined in wild type and Toll-like receptor 4 (TLR4) mutant mice after bile duct ligation (BDL). In vitro studies were carried out to evaluate the effect of the bacterial product and TLR agonist lipopolysaccharide (LPS) on paracrine interactions between hepatic stellate cells (HSC) and liver endothelial cells (LEC) that lead to fibrosis and portal hypertension.

RESULTS

Portal pressure, fibrosis, and angiogenesis were significantly lower in BDL mice receiving rifaximin compared to BDL mice receiving vehicle. Studies in TLR4 mutant mice confirmed that the effect of rifaximin was dependent on LPS/TLR4 pathway. Fibronectin (FN) was increased in the BDL liver and was reduced by rifaximin administration and thus, was explored further in vitro as a potential mediator of paracrine interactions of HSC and LEC. In vitro, LPS promoted FN production from HSC. Furthermore, HSC-derived FN promoted LEC migration and angiogenesis.

CONCLUSIONS

These studies expand our understanding of the relationship of intestinal microbiota with fibrosis development by identifying FN as a TLR4 dependent mediator of the matrix and vascular changes that characterize cirrhosis.

Changes of fecal Bifidobacterium species in adult patients with hepatitis B virus-induced chronic liver disease

The beneficial effects of Bifidobacteria on health have been widely accepted. Patients with chronic liver disease have varying degrees of intestinal microflora imbalance with a decrease of total Bifidobacterial counts. Since different properties have been attributed to different Bifidobacterium species and there is no information available for the detailed changes in the genus Bifidobacterium in patients with chronic liver disease heretofore, it is meaningful to investigate the structure of this bacterium at the species level in these patients. The aim of this study was to characterize the composition of intestinal Bifidobacterium in patients with hepatitis B virus-induced chronic liver disease. Nested-PCR-based denaturing gradient gel electrophoresis (PCR-DGGE), clone library, and real-time quantitative PCR were performed on the fecal samples of 16 patients with chronic hepatitis B (CHB patients), 16 patients with hepatitis B virus-related cirrhosis (HBV cirrhotics), and 15 healthy subjects (Controls). Though there was no significant difference in the diversity among the three groups (P = 0.196), Bifidobacterium dentium seems to be specifically enhanced in patients as the PCR-DGGE profiles showed, which was further validated by clone library and real-time quantitative PCR. In contrast to the B. dentium, Bifidobacterium catenulatum/Bifidobacterium pseudocatenulatum were detected less frequently in the predominant profile and by quantitative PCR in HBV cirrhotics than in the controls, and the level of this species was also significantly different between these two groups (P = 0.023). Although having no quantitative difference among the three groups, Bifidobacterium longum was less commonly detected in HBV cirrhotics than in CHB patients and Controls by quantitative PCR (P = 0.011). Thus, the composition of intestinal Bifidobacterium was deeply altered in CHB and HBV cirrhotic patients with a shift from beneficial species to opportunistic pathogens. The results provide further insights into the dysbiosis of the intestinal microbiota in patients with hepatitis B virus-induced chronic liver disease and might potentially serve as guidance for the probiotics interventions of these diseases.

Effects of perioperative synbiotic treatment on infectious complications, intestinal integrity, and fecal flora and organic acids in hepatic surgery with or without cirrhosis

BACKGROUND

The aim of this study was to assess the effect of preoperative and postoperative synbiotic treatment in hepatectomy patients with or without liver cirrhosis.

METHODS

Sixty-one patients with hepatic cancer were assigned randomly to receive either oral synbiotics that consisted of Bifidobacterium, Lactobacillus, and galactooligosaccharides or no synbiotics (control) preoperatively for 14 days and postoperatively for 11 days. Infectious complications, intestinal mucosal integrity as measured by serum diamine oxidase (DAO) activity, and fecal flora and organic acid concentrations were compared between synbiotic treatment (n = 32) and control (n = 29) groups.

RESULTS

Fecal flora culture and organic acid concentrations were changed after hepatectomy in both groups. The postsurgery decrease in DAO activity was less profound in the synbiotic-treated group (P < .01) and was correlated negatively with serum interleukin 6 and C-reactive protein concentrations (P < .001). Infectious complications occurred in 5 (17.2%) patients in the control group and no patients in the synbiotic-treated group (P < .05).

CONCLUSION

Perioperative synbiotic treatment attenuated the decrease in intestinal integrity and reduced the rate of infectious complications in patients with or without liver cirrhosis who underwent hepatic surgery.

Liver transplantation in patients with liver cirrhosis and active pneumonia: an observational study

Patients with chronic liver disease are at high risk for severe infection because of increased bacterial translocation and immune suppression associated with liver dysfunction. Patients presenting with severe pneumonia and acute decompensation of cirrhosis are generally not considered for liver transplantation because it is unknown if these patients can recover from infection while under immunosuppression. We performed an observational study where patients with cirrhosis of the liver remained on the waiting list, although suffering from active pneumonia. Nine patients were included, but only six patients improved under goal-directed therapy and subsequently underwent liver transplantation. All six patients recovered quickly from infection; five patients recovered without sequelae and one patient died because of late complications. We propose that in patients with chronic liver disease and active pneumonia transplantation is a treatment option that should not hastily be abandoned.

Characterization of fecal microbial communities in patients with liver cirrhosis

Liver cirrhosis is the pathologic end stage of chronic liver disease. Increasing evidence suggests that gut flora is implicated in the pathogenesis of liver cirrhosis complications. The aim of this study was to characterize the fecal microbial community in patients with liver cirrhosis in comparison with healthy individuals. We recruited 36 patients with liver cirrhosis and 24 healthy controls. The fecal microbial communities was analyzed by way of 454 pyrosequencing of the 16S ribosomal RNA V3 region followed by real-time quantitative polymerase chain reaction. Community-wide changes of fecal microbiota in liver cirrhosis were observed compared with healthy controls. The proportion of phylum Bacteroidetes was significantly reduced (P=0.008), whereas Proteobacteria and Fusobacteria were highly enriched in the cirrhosis group (P=0.001 and 0.002, respectively). Enterobacteriaceae (P=0.001), Veillonellaceae (P=0.046), and Streptococcaceae (P=0.001) were prevalent in patients with cirrhosis at the family level. A positive correlation was observed between Child-Turcotte-Pugh (CTP) score and Streptococcaceae (R=0.386, P=0.02). Lachnospiraceae decreased significantly in patients with cirrhosis (P=0.004) and correlated negatively with CTP score (R=-0.49, P=0.002). Using partial least square discriminate analysis, we identified 149 operational taxonomic units (OTUs) as key phylotypes that responded to cirrhosis, most of which were Lachnospiraceae (65 OTUs), Streptococcaceae (23 OTUs), and Veillonellaceae (21 OTUs).

CONCLUSION

Fecal microbial communities are distinct in patients with cirrhosis compared with healthy individuals. The prevalence of potentially pathogenic bacteria, such as Enterobacteriaceae and Streptococcaceae, with the reduction of beneficial populations such as Lachnospiraceae in patients with cirrhosis may affect prognosis.

Prevalence of spontaneous bacterial peritonitis in asymptomatic inpatients with decompensated liver cirrhosis - a pilot study

PURPOSE

To assess the prevalence of spontaneous bacterial peritonitis (SBP) in asymptomatic patients with decompensated liver cirrhosis.

MATERIAL AND METHODS

Patients (pts) with symptoms of decompensation of liver cirrhosis, ascites, and no signs indicating SBP were included to our study. Exclusion criteria include: 1/ clinical symptoms of infection, 2/ developing de novo or worsening hepatic encephalopathy, 3/ gastrointestinal bleeding within the last month, 4/ renal failure, 5/ antibiotic treatment or norfloxacin prophylaxis at admission. About 60 ml of ascitic fluid were drawn for lab examination. Pathologic assessment for atypical cells was also performed.

RESULTS

37 patients fulfilled inclusion criteria. Their mean age was 56.2 ± 12.1. The Child-Pugh classification revealed 13 (35.1%) patients of class B and 24 (64.9%) patients of class C. The mean Model for End-Stage Liver Disease score in this group was 16.6 ± 6.8. The mean ascitic protein content was 1.85 ± 1.09 g/dL and mean neutrophil count 144.8 ± 445.1/mm3. Ascitic fluid analysis revealed: signs of bacterascites in 6 of 37 (16.2%) pts; neutrocytic ascites in 1 of 37 (2.7%) pts; and 2 of 37 (5.4%) pts met criteria for SBP. C-reactive protein level was the best predictor of infection [SBP(+) 47.9 ± 40.9 versus SBP(-) 11.7 ± 5.1; p= 0.0005].

CONCLUSIONS

The prevalence of SBP in asymptomatic cirrhotics with ascites is low. We observed the trend towards more frequent occurrence of the infection in patients suffered from severe liver disease (Child-Pugh C group).