Coffee consumption protects against progression in liver cirrhosis and increases long-term survival after liver transplantation

The microbiota and the gut-liver axis in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) offers unique opportunities to explore the gut-liver axis owing to the close association between liver disease and colonic inflammation. It is well established that the gut microbiota in people with PSC differs from that of healthy individuals, but details of the microbial factors that demarcate PSC from inflammatory bowel disease (IBD) without PSC are poorly understood. In this Review, we aim to provide an overview of the latest literature on the gut microbiome in PSC and PSC with IBD, critically examining hypotheses on how microorganisms could contribute to the pathogenesis of PSC. A particular emphasis will be put on pathogenic features of the gut microbiota that might explain the occurrence of bile duct inflammation and liver disease in the context of IBD, and we postulate the potential existence of a specific yet unknown factor related to the gut-liver axis as causative in PSC. Available data are scrutinized in the perspective of therapeutic approaches related to the gut-liver axis.

UDP-glucuronosyltransferases mediate coffee-associated reduction of liver fibrosis in bile duct ligated humanized transgenic UGT1A mice

BACKGROUND

Coffee consumption has been shown to reduce the risk of liver fibrosis and is capable of inducing human UDP-glucuronosyltransferase (UGT) 1A genes. UGT1A enzymes act as indirect antioxidants catalyzing the elimination of reactive metabolites, which in turn are potent initiators of profibrotic mechanisms. The aim of this study was to analyze the role of UGT1A genes as effectors of the protective properties of coffee in bile duct ligation (BDL) induced liver fibrosis.

METHODS

Fourteen days BDL with and without coffee pre- and co-treatment was performed in htgUGT1A-WT and htgUGT1A-SNP mice. Hepatic UGT1A mRNA expression levels, serum bilirubin and aminotransferase activities were determined. Liver fibrosis was assessed by collagen deposition, computational analysis of Sirius red tissue staining and expression of profibrotic marker genes. Oxidative stress was measured by hepatic peroxidase concentrations and immunofluorescence staining.

RESULTS

UGT1A transcription was differentially activated in the livers of htgUGT1A-WT mice after BDL, in contrast to a reduced or absent induction in the presence of SNPs. Co-treated (coffee + BDL) htgUGT1A-WT-mice showed significantly increased UGT1A expression and protein levels and a considerably higher induction compared to water drinking WT mice (BDL), whereas in co-treated htgUGT1A-SNP mice absolute expression levels remained below those observed in htgUGT1A-WT mice. Collagen deposition, oxidative stress and the expression of profibrotic markers inversely correlated with UGT1A expression levels in htgUGT1A-WT and SNP mice after BDL and coffee + BDL co-treatment.

CONCLUSIONS

Coffee exerts hepatoprotective and antioxidative effects via activation of UGT1A enzymes. Attenuated hepatic fibrosis as a result of coffee-mediated UGT1A induction during cholestasis was detected, while the protective action of coffee was lower in a common low-function UGT1A SNP haplotype present in 10% of the Caucasian population. This study suggests that coffee consumption might constitute a potential strategy to support the conventional treatment of cholestasis-related liver diseases.

Diet affects gut microbiota and modulates hospitalization risk differentially in an international cirrhosis cohort

The relative ranking of cirrhosis-related deaths differs between high-/middle-income countries. Gut microbiome is affected in cirrhosis and is related to diet. Our aim was to determine the effect of differing dietary habits on gut microbiota and clinical outcomes. Outpatient compensated/decompensated patients with cirrhosis and controls from Turkey and the United States underwent dietary and stool microbiota analysis. Patients with cirrhosis were followed till 90-day hospitalizations. Shannon diversity and multivariable determinants (Cox and binary logistic) of microbial diversity and hospitalizations were studied within/between groups. Two hundred ninety-six subjects (157 U.S.: 48 controls, 59 compensated, 50 decompensated; 139 Turkey: 46 controls, 50 compensated, 43 decompensated) were included. Patients with cirrhosis between cohorts had similar Model for End-Stage Liver Disease (MELD) scores. American patients with cirrhosis had more men, greater rifaximin/lactulose use, and higher hepatitis C/alcohol etiologies. Coffee intake was higher in Americans whereas tea, fermented milk, and chocolate intake were higher in Turkey. The entire Turkish cohort had a significantly higher microbial diversity than Americans, which did not change between their controls and patients with cirrhosis. In contrast, microbial diversity changed in the U.S.-based cohort and was the lowest in decompensated patients. Coffee, tea, vegetable, chocolate, and fermented milk intake predicted a higher diversity whereas MELD score, lactulose use, and carbonated beverage use predicted a lower microbial diversity. The Turkish cohort had a lower risk of 90-day hospitalizations. On Cox and binary logistic regression, microbial diversity was protective against 90-day hospitalizations, along with coffee/tea, vegetable, and cereal intake.

CONCLUSION

In this study of patients with cirrhosis and healthy controls from the United States and Turkey, a diet rich in fermented milk, vegetables, cereals, coffee, and tea is associated with a higher microbial diversity. Microbial diversity was associated with an independently lower risk of 90-day hospitalizations. (Hepatology 2018;68:234-247).

Protective effect of coffee consumption on all-cause mortality of French HIV-HCV co-infected patients

BACKGROUND & AIMS

Coffee has anti-inflammatory and hepato-protective properties. In the general population, drinking ≥3cups of coffee/day has been associated with a 14% reduction in the risk of all-cause mortality. The aim of this study was to investigate the relationship between coffee consumption and the risk of all-cause mortality in patients co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV).

METHODS

ANRS CO13 HEPAVIH is an ongoing French nationwide prospective cohort of patients co-infected with HIV-HCV collecting both medical and psychosocial/behavioural data (annual self-administered questionnaires). We used a Cox proportional hazards model to estimate the effect of elevated coffee consumption (≥3cups/day) at baseline on all-cause mortality during the cohort's five-year follow-up.

RESULTS

Over a median [interquartile range] follow-up of 5.0 [3.9-5.9] years, 77 deaths occurred among 1,028 eligible patients (mortality rate 1.64/100 person-years; 95% confidence interval [CI] 1.31-2.05). Leading causes of death were HCV-related diseases (n=33, 43%), cancers unrelated to AIDS/HCV (n=9, 12%), and AIDS (n=8, 10%). At the first available visit, 26.6% of patients reported elevated coffee consumption. Elevated coffee consumption at baseline was associated with a 50% reduced risk of all-cause mortality (hazard ratio 0.5; CI 0.3-0.9; p=0.032), after adjustment for gender and psychosocial, behavioral and clinical time-varying factors.

CONCLUSIONS

Drinking three or more cups of coffee per day halves all-cause mortality risk in patients co-infected with HIV-HCV. The benefits of coffee extracts and supplementing dietary intake with other anti-inflammatory compounds need to be evaluated in this population.

LAY SUMMARY

Coffee has anti-inflammatory and hepato-protective properties but its effect on mortality risk has never been investigated in patients co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). This study shows that elevated coffee consumption (≥3cups/day) halves all-cause mortality risk in patients co-infected with HIV-HCV. The benefits of coffee extracts and supplementing dietary intake with other anti-inflammatory compounds need to be evaluated in this population.

Autophagy mediated by endoplasmic reticulum stress enhances the caffeine-induced apoptosis of hepatic stellate cells

Caffeine has been identified to have beneficial effects against chronic liver diseases, particularly liver fibrosis. Many studies have reported that caffeine ameliorates liver fibrosis by directly inducing hepatic stellate cell (HSC) apoptosis; however, the molecular mechanisms involved in this process remain unclear. The presents study aimed to detect the underlying mechanisms by which caffeine mediates HSC apoptosis and eliminates activated HSCs. For this purpose, the LX-2 cell line was applied in this study and the cells were exposed to various concentrations of caffeine for the indicated times. The effects of caffeine on cell viability and apoptosis were assessed by Cell Counting Kit-8 assay and flow cytometry, respectively. Autophagy and endoplasmic reticulum (ER) stress were explored by morphological assessment and western blotting. In the present study, caffeine was found to inhibit the viability and increase the apoptosis of the LX-2 cells in dose- and time-dependent manners. ER stress was stimulated by caffeine as demonstrated by increased levels of GRP78/BiP, CHOP and inositol-requiring enzyme 1 (IRE1)-α as well as many enlarged ERs detected by electron microscopy. Caffeine induced autophagy as shown by increased p62 and LC3II accumulation and the number of GFP/RFP-LC3 puncta and autophagosomes/autolysosomes. Moreover, IRE1-α knockdown decreased the level of autophagic flux, and inhibition of autophagy protected LX-2 cells from apoptotic death. In conclusion, our study showed that the caffeine-enhanced autophagic flux in HSCs was stimulated by ER stress via the IRE1-α signaling pathway, which further weakened HSC viability via the induction of apoptosis. These findings provide new insight into the mechanism of caffeine's anti-fibrotic effects.

Coffee consumption prevents fibrosis in a rat model that mimics secondary biliary cirrhosis in humans

Investigations demonstrated that oxidative stress plays an important role in injury promotion in cholestatic liver disease. We hypothesized that coffee attenuates cholestasis-induced hepatic necrosis and fibrosis via its antioxidant, anti-inflammatory, and antifibrotic properties. The major aim of this study was to evaluate the hepatoprotective properties of coffee and caffeine in a model of chronic bile duct ligation (BDL) in male Wistar rats. Liver injury was induced by 28-day BDL, and conventional coffee, decaffeinated coffee, or caffeine was administered daily. After treatment, the hepatic oxidative status was estimated by measuring lipid peroxidation, the reduced to oxidized glutathione ratio, and glutathione peroxidase. Fibrosis was assessed by measuring the liver hydroxyproline content. The transforming growth factor-β, connective tissue growth factor, α-smooth muscle actin, collagen 1, and interleukin-10 proteins and mRNAs were measured by Western blot and polymerase chain reaction, respectively. Conventional coffee suppressed most of the changes produced by BDL; however, caffeine showed better antifibrotic effects. Coffee demonstrated antioxidant properties by restoring the redox equilibrium, and it also prevented the elevation of liver enzymes as well as hepatic glycogen depletion. Interestingly, coffee and caffeine administration prevented collagen increases. Western blot assays showed decreased expression levels of transforming growth factor-β, connective tissue growth factor, α-smooth muscle actin, and collagen 1 in the coffee- and caffeine-treated BDL groups. Similarly, coffee decreased the mRNA levels of these proteins. We conclude that coffee prevents liver cirrhosis induced by BDL by attenuating the oxidant processes, blocking hepatic stellate cell activation, and downregulating the main profibrotic molecules involved in extracellular matrix deposition.