NASH and atherosclerosis are two aspects of a shared disease: Central role for macrophages

Macrophage infiltration into the atherosclerotic lesion is known to play a central role in the initiation of atherosclerosis. In contrast, the role of macrophages during the etiology of non-alcoholic steatohepatitis (NASH) has been considered to be merely a late consequence of steatosis. However, recent insights suggest that macrophage activation and infiltration is also an early initiating event in NASH and thereby point to the shared etiology of atherosclerosis and NASH. In this review, we put forward the hypothesis that NASH and atherosclerosis are actually two aspects of a shared disease, involving the local presence of activated macrophages. We will review the current data supporting the shared mechanisms and also discuss the implications.