Liver Fibrosis Leading to Cirrhosis: Basic Mechanisms and Clinical Perspectives

Liver fibrosis is the pathological deposition of extracellular matrix rich in fibrillar collagen within the hepatocytes in response to chronic liver injury due to various causes. As the condition advances, it can progress to cirrhosis, the late stages of which are irreversible. Multiple pathophysiological mechanisms and cell types are responsible for the progression of liver fibrosis and cirrhosis. Hepatic stellate cells and myofibroblast activation represent a key event in fibrosis. Capillarization of liver sinusoidal endothelial cells further contributes to extracellular matrix deposition and an increase in portal pressure. Macrophages and neutrophils produce inflammatory cytokines and participate in activating hepatic stellate cells. Although initially believed to be irreversible, early stages of fibrosis are now found to be reversible. Furthermore, advances in noninvasive imaging and serum studies have changed and improved how cirrhosis can be evaluated and monitored. Although there are currently no specific approved therapies to reverse liver fibrosis, management of underlying diseases has been found to halt the progression, and to an extent, even reverse liver fibrosis, preventing further liver injury and cirrhosis-related complications.