Fibrosis Severity as a Determinant of Cause-Specific Mortality in Patients With Advanced Nonalcoholic Fatty Liver Disease: A Multi-National Cohort Study

Background & Aims Little is known about the natural course of nonalcoholic fatty liver disease (NAFLD) with advanced fibrosis. We describe long-term outcomes and evaluate the effects of clinical and histologic parameters on disease progression in patients with advanced NAFLD. Methods We conducted a multi-national study of 458 patients with biopsy-confirmed NAFLD with bridging fibrosis (F3, n = 159) or compensated cirrhosis (222 patients with Child-Turcotte-Pugh scores of A5 and 77 patients with scores of A6), evaluated from April 1995 through November 2013 and followed until December 2016, death, or liver transplantation at hepatology centers in Spain, Australia, Hong Kong, and Cuba. Biopsies were re-evaluated and scored; demographic, clinical, laboratory, and pathology data for each patient were collected from the time of liver biopsy collection. Cox proportional and competing risk models were used to estimate rates of transplantation-free survival and major clinical events and to identify factors associated with outcomes. Results During a mean follow-up time of 5.5 years (range, 2.7–8.2 years), 37 patients died, 37 received liver transplants, 88 had initial hepatic decompensation events, 41 developed hepatocellular carcinoma, 14 had vascular events, and 30 developed nonhepatic cancers. A higher proportion of patients with F3 fibrosis survived transplantation-free for 10 years (94%; 95% confidence interval [CI], 86%–99%) than of patients with cirrhosis and Child-Turcotte-Pugh A5 (74%; 95% CI, 61%–89%) or Child-Turcotte-Pugh A6 (17%; 95% CI, 6%–29%). Patients with cirrhosis were more likely than patients with F3 fibrosis to have hepatic decompensation (44%; 95% CI, 32%–60% vs 6%, 95% CI, 2%–13%) or hepatocellular carcinoma (17%; 95% CI, 8%–31% vs 2.3%, 95% CI, 1%–12%). The cumulative incidence of vascular events was higher in patients with F3 fibrosis (7%; 95% CI, 3%–18%) than cirrhosis (2%; 95% CI, 0%–6%). The cumulative incidence of nonhepatic malignancies was higher in patients with F3 fibrosis (14%; 95% CI, 7%–23%) than cirrhosis (6%; 95% CI, 2%–15%). Death or transplantation, decompensation, and hepatocellular carcinoma were independently associated with baseline cirrhosis and mild (<33%) steatosis, whereas moderate alcohol consumption was associated with these outcomes only in patients with cirrhosis. Conclusions Patients with NAFLD cirrhosis have predominantly liver-related events, whereas those with bridging fibrosis have predominantly nonhepatic cancers and vascular events

Deletion of GPR21 improves glucose homeostasis and inhibits the CCL2-CCR2 axis by divergent mechanisms

International audienceIntroduction: A potential role for the orphan G protein-coupled receptor, GPR21, in linking immune cell infiltration into tissues and obesity-induced insulin resistance has been proposed, although limited studies in mice are complicated by non-selective deletion of Gpr21.Research design and methods: We hypothesized that a Gpr21-selective knockout mouse model, coupled with type 2 diabetes patient samples, would clarify these issues and enable clear assessment of GPR21 as a potential therapeutic target.Results: High-fat feeding studies in Gpr21-/- mice revealed improved glucose tolerance and modest changes in inflammatory gene expression. Gpr21-/- monocytes and intraperitoneal macrophages had selectively impaired chemotactic responses to monocyte chemoattractant protein (MCP)-1, despite unaltered expression of Ccr2. Further genotypic analysis revealed that chemotactic impairment was due to dysregulated monocyte polarization. Patient samples revealed elevated GPR21 expression in peripheral blood mononuclear cells in type 2 diabetes, which was correlated with both %HbA1c and fasting plasma glucose levels.Conclusions: Collectively, human and mouse data suggest that GPR21 influences both glucose homeostasis and MCP-1/CCL2-CCR2-driven monocyte migration. However, a Gpr21-/- bone marrow transplantation and high-fat feeding study in mice revealed no effect on glucose homeostasis, suggesting that there is no (or limited) overlap in the mechanism involved for monocyte-driven inflammation and glucose homeostasis