No abstract

Although bacterial endotoxin, such as lipopolysaccharide (LPS), plays a key role in the pathogenesis of nonalcoholic steatohepatitis (NASH), detailed mechanisms of this pathogenesis remain unclear. Here, we demonstrate that upregulation of CD14 by leptin-mediated signaling is critical to hyperreactivity against endotoxin during NASH progression. Upregulation of CD14 in Kupffer cells and hyperreactivity against low-dose LPS were observed in high-fat diet (HFD)-induced steatosis mice, but not chow-fedcontrol mice. Hyperresponsivity against low-dose LPS led to accelerated NASH progression, including liver inflammation and fibrosis. Administering leptin in chow-fed mice caused increased hepatic expression of CD14 via STAT3 signaling, resulting in hyperreactivity against low-dose LPS without steatosis. In contrast, a marked decrease in hepatic CD14 expression was observed in leptin-deficient ob/ob mice, despite severe steatosis. Our results indicate that obesity-induced leptin plays a crucial role in NASH progression via enhanced responsivity to endotoxin, and we propose a mechanism of bacteria-mediated progression of NASH.

There is a significant positive correlation between median velocity measured by using ARFI sonoelastography and severity of liver fibrosis in patients with NAFLD. The results of ARFI sonoelastography were similar to those of transient sonoelastography.

Rubicon is overexpressed and plays a pathogenic role in NAFLD by accelerating hepatocellular lipoapoptosis and lipid accumulation, as well as inhibiting autophagy. Rubicon may be a novel therapeutic target for regulating NAFLD development and progression. (Hepatology 2016;64:1994-2014).

This is the first report to demonstrate consistent and profound elevation of hs-CRP in cases of NASH compared with in cases of simple nonprogressive steatosis. Our results suggest that hs-CRP may be a clinical feature that not only distinguishes NASH from simple nonprogressive steatosis but also indicates the severity of hepatic fibrosis in cases of NASH.