Abstract
Obesity and high-fat diet (HFD) are known to cause proinflammatory and procoagulation states and suggested to become a risk of developing thromboembolic diseases. Non-alcoholic fatty liver disease (NAFLD) is usually associated with obesity and HFD, and a part of NAFLD is known to progress to nonalcoholic steatohepatitis (NASH), the pathogenesis of which has not been fully elucidated. In the current study, we examined the influence of short-term HFD on hepatic expression of the molecules related to inflammation, coagulation, metabolism, and cellular stresses from the perspective that HFD itself can be a risk for the development to NASH. In the analysis in short-term (4 days to 14 days) HFD-fed mice, we found out that HFD increased hepatic expression of IFN-γ, TNF-α, IL-10, monocyte chemotactic protein-1 (MCP-1), tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1) mRNAs, and fibrin/fibrinogen deposition in the liver tissues. And it was suggested that metabolic alterations and endoplasmic reticulum (ER) stresses induced by the HFD intake were associated with this proinflammatory and procoagulation states. When we administered concanavalin A (Con A) to these HFD-fed mice, the extent of liver injury was dramatically exacerbated in HFD-fed mice. Heparin treatment to Con A-administered, HFD-fed mice (for 4 days) profoundly ameliorated the extent of liver injury. These suggest that even short-term of HFD intake induces proinflammatory and procoagulation states in the liver and thereby increases the susceptibility of the liver to circulating inflammatory stimuli. We think that it may explain a part of NASH pathogenesis.