Cellular and molecular basis of fibrogenesis in NASH

Fibrosis due to nonalcoholic steatohepatitis (NASH) develops primarily in the pericentral areas, where thin bundles of fibrotictic tissue surround groups of hepatocytes and thicken the space of Disse. The pericellular fibrosis eventually forms septa isolating regenerating nodules. The major cell type responsible for extracellular matrix deposition in this context is represented by activated hepatic stellate cells (HSCs). The profibrogenic mechanisms operating in NASH are partly in common with those observed in other chronic liver diseases, particularly alcohol-mediated liver damage. Nonetheless, some specific molecular actions are related to the excess adiposity and fat-mediated liver damage.