Evolving Role for Pharmacotherapy in NAFLD/NASH

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent, dynamic disease that occurs across the age spectrum and can lead to cirrhosis and hepatocellular carcinoma. There are currently no US Food and Drug Administration (FDA) approved treatments for NAFLD; however, this is a field of active research. This review summarizes emerging pharmacotherapies for the treatment of adult and pediatric NAFLD. Investigated pharmacotherapies predominantly target bile acid signaling, insulin resistance, and lipid handling within the liver. Three drugs have gone on to phase III trials for which results are available. Of those, obeticholic acid is the single agent that demonstrates promise according to the interim analyses of the REGENERATE trial. Obeticholic acid showed reduction of fibrosis in adults with nonalcoholic steatohepatitis (NASH) taking 25 mg daily for 18 months (n = 931, reduction in fibrosis in 25% vs. 12% placebo, P \u3c 0.01). Ongoing phase III trials include REGENERATE and MAESTRO-NASH, which investigates thyroid hormone receptor-β agonist MGL-3196. Outcomes of promising phase II trials in adults with NASH are also available and those have investigated agents, including the fibroblast growth factor (FGF)19 analogue NGM282, the GLP1 agonist liraglutide, the FGF21 analogue Pegbelfermin, the sodium glucose co-transporter 2 inhibitor Empagliflozin, the ketohexokinase inhibitor PF-06835919, the acetyl-coenzyme A carboxylase inhibitor GS-0976, and the chemokine receptor antagonist Cenicriviroc. Completed and ongoing clinical trials emphasize the need for a more nuanced understanding of the phenotypes of subgroups within NAFLD that may respond to an individualized approach to pharmacotherapy

Impaired Bile Acid Homeostasis in Children with Severe Acute Malnutrition

OBJECTIVE:Severe acute malnutrition (SAM) is a major cause of mortality in children under 5 years and is associated with hepatic steatosis. Bile acids are synthesized in the liver and participate in dietary fat digestion, regulation of energy expenditure, and immune responses. The aim of this work was to investigate whether SAM is associated with clinically relevant changes in bile acid homeostasis. DESIGN:An initial discovery cohort with 5 healthy controls and 22 SAM-patients was used to identify altered bile acid homeostasis. A follow up cohort of 40 SAM-patients were then studied on admission and 3 days after clinical stabilization to assess recovery in bile acid metabolism. Recruited children were 6-60 months old and admitted for SAM in Malawi. Clinical characteristics, feces and blood were collected on admission and prior to discharge. Bile acids, 7α-hydroxy-4-cholesten-3-one (C4) and FGF-19 were quantified. RESULTS:On admission, total serum bile acids were higher in children with SAM than in healthy controls and glycine-conjugates accounted for most of this accumulation with median and interquartile range (IQR) of 24.6 μmol/L [8.6-47.7] compared to 1.9 μmol/L [1.7-3.3] (p = 0.01) in controls. Total serum bile acid concentrations did not decrease prior to discharge. On admission, fecal conjugated bile acids were lower and secondary bile acids higher at admission compared to pre- discharge, suggesting increased bacterial conversion. FGF19 (Fibroblast growth factor 19), a marker of intestinal bile acid signaling, was higher on admission and was associated with decreased C4 concentrations as a marker of bile acid synthesis. Upon recovery, fecal calprotectin, a marker of intestinal inflammation, was lower. CONCLUSION:SAM is associated with increased serum bile acid levels despite reduced synthesis rates. In SAM, there tends to be increased deconjugation of bile acids and conversion from primary to secondary bile acids, which may contribute to the development of liver disease

Assessment of Intestinal Microbiota in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) includes simple hepatic steatosis (SS) and non-alcoholic steatohepatitis (NASH). NAFLD is tightly linked to obesity and is thought to be secondary to various noxious signals, some of which may originate from the intestinal microbiota (IM). Despite a growing body of evidence supporting a link between obesity and altered IM, there are no studies assessing the IM of patients with NAFLD. In this cross-sectional study we aimed at comparing fecal levels of total bacteria, Bacteroidetes, C. coccoides, C. leptum, Bifidobacteria, E. coli, and Archaea between healthy controls (HC) and patients with SS or NASH. We found higher C. coccoides levels in NASH compared to SS and lower percentage Bacteroidetes in NASH compared to SS and HC. Controlling for body mass index and fat intake we found an association between presence of NASH and percentage Bacteroidetes. The latter inversely correlated with insulin resistance.MAS

Insights into the evolving role of the gut microbiome in nonalcoholic fatty liver disease: rationale and prospects for therapeutic intervention

Nonalcoholic fatty liver disease (NAFLD) is diagnosed across the age spectrum and contributes to significant morbidity and mortality. The pathophysiology of NAFLD is not entirely understood; however, recent evidence has implicated the intestinal microbiome. Through the effects on host appetite, energy expenditure, digestion, gene expression, intestinal permeability, as well as immune activation, a dysbiotic microbiome can contribute to the development and progression of the hepatocellular steatosis, inflammation and fibrosis seen in the context of NAFLD. As such, intestinal microbiota and products of their metabolism have been targeted as treatment approaches for NAFLD

An Update on the Role of the Microbiome in Non-alcoholic Fatty Liver Disease Pathogenesis, Diagnosis, and Treatment

The microbiome was originally postulated to contribute to the pathogenesis of NAFLD when the first studies of dysbiosis in NAFLD were reported. Since then, a number of studies have investigated this finding further, in order to discern whether the dysbiosis is the result of the metabolic dysregulation seen with NAFLD or a contributor to the pathogenesis of this condition

More Frequent Clinic Visits Are Associated with Improved Outcomes for Children with NAFLD

Objective. Adult data suggest that frequent monitoring of patients with nonalcoholic fatty liver disease (NAFLD) may be associated with improved outcomes. The optimal frequency of outpatient visits for the management of pediatric NAFLD remains unknown. Study Design. In this retrospective study, two cohorts of patients with NAFLD, one followed on a yearly basis and one followed on 3-month intervals, were included. Both received similar advice regarding lifestyle changes. Primary outcome was change in BMI z-scores over a year. Secondary outcomes were the change in serum transaminases and markers of metabolic dysregulation. Results. Fifty-six patients were included (28 per group). The majority (71%) were male with a mean (±SD) age of 12.2 (±2.7) years. At baseline, there were no differences in BMI z-scores (2.8 versus 2.9; p=0.72) and ALT levels (101 versus 100 U/L; p=0.95) between the groups (yearly versus three-month, resp.). Twelve months later, those followed on a 3-month basis demonstrated a significant decrease in BMI (net BMI z-score change = −0.06; p=0.37), accompanied by a significant improvement in serum ALT (−25 U/L; p<0.01) and AST (−13 U/L; p=0.03) levels. There were no differences in fasting lipid profiles. Conclusion. Frequent clinic visits are associated with improved outcomes in pediatric NAFLD