Gut microbiome changes in Nonalcoholic fatty liver disease & alcoholic liver disease

Abstract

Nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) are some of the most common liver diseases worldwide. The human gut microbiome is dynamic and shifts in bacterial composition have been implicated in many diseases. Studies have shown that there is a shift in bacterial overgrowth favoring pro-inflammatory mediators in patients with advanced disease progression such as cirrhosis. Further investigation demonstrated that the transplantation of gut microbiota from advanced liver disease patients can reproduce severe liver inflammation and injury in mice. Various techniques in manipulating the gut microbiota have been attempted including fecal transplantation and probiotics. This review focuses on the changes in the gut microbiota as well as emerging lines of microbiome work with respect to NAFLD and ALD.

Non-alcoholic fatty liver disease is a risk factor for occurrence of hepatocellular carcinoma after sustained virologic response in chronic hepatitis C patients: A prospective four-years follow-up study

“…Human gut microbiota plays a pivotal role in the development of NAFLD and HCC. Gut microbiota generates a variety of bioactive substances such as lipopolysaccharides, peptidoglycan, DNA, and extracellular vesicles, short-chain fatty acids, secondary bile acids, indole and its derivatives, trimethylamine, carotenoids, and phenolic compounds [ [31] , [32] , [33] ]. Gut microbiota alteration might lead to increased gut permeability, translocation of microbiota products from the gut to liver via the portal vein.…”

Perspectives on Precision Medicine Approaches to NAFLD Diagnosis and Management

“…As discussed above (“ Intestinal Microbiota ”), “microbiome signatures” can be used for personalizing NAFLD diagnosis and staging. Moreover, these could also be useful for selecting patients to submit to therapeutic fecal microbiota transplantation (FMT) as well as biomarkers of response to therapy [ 142 ]. This is relevant considering that not all patients have either gut dysbiosis or increased intestinal permeability [ 143 ] and that it is very likely that certain subsets of patients will respond better to microbiota-targeted therapies than others.…”

“…This is relevant considering that not all patients have either gut dysbiosis or increased intestinal permeability [ 143 ] and that it is very likely that certain subsets of patients will respond better to microbiota-targeted therapies than others. Therefore, microbiome-based biomarkers could be applied for developing more targeted management approaches such as dietary interventions, manipulation of gut microbiota through the use of probiotics, prebiotics, and/or synbiotics as well as FMT or bacteriophage therapy [ 71 , 142 ]. To date, studies on the use of probiotics and synbiotics in NAFLD suggest some benefit in terms of amelioration of hepatic inflammation, steatosis, and eventually liver fibrosis [ 144 ], but data heterogeneity is significant and well-designed RCTs are lacking.…”

Small and Large Intestine (I): Malabsorption of Nutrients

“…Overall, SIBO is responsible for approximately 10‒20% of nonresponsive celiac disease [ 28 , 29 , 30 ], though some studies suggest that SIBO may coexist with other disorders associated with nonresponsive CD [ 30 ]. SIBO has been frequently documented in association with alcoholic or nonalcoholic liver disease [ 31 , 32 ], and is more likely in patients with decompensated cirrhosis of the liver with portal hypertension, ascites, and jaundice. Intestinal bacteria are clearly fundamental to overt hepatic encephalopathy and even minimal hepatic encephalopathy.…”