Re-Examining the Role of Pulmonary Lipids in the Pathogenesis of Pulmonary Fibrosis.

ABSTRACT

Pulmonary fibrosis (PF) can be idiopathic or driven by a specific insult or disease process. Inflammation plays a role in the pathophysiology, the extent of which remains a longstanding topic of debate. More recently there has been increasing interest in a potential inciting role for aberrant lipid metabolism. Lipids are essential for the structure and function of all cell membranes but specifically in the lung for surfactant composition, intra and intercellular lipid mediators and lipofibroblasts. Clinically, there is evidence of increased lipid deposition in the subpleural space, and at a whole lung tissue level in PF. There is evidence of increased parenchymal lipid deposition and abnormal mediastinal fat shape on chest CT. A protective role for cholesterol lowering drugs including statins and ezetimibe has been described in PF. At a cellular level, fatty acid (FA), phospholipid (PL) and glucose metabolism are disordered, as is the production of lipid mediators. In this perspectives piece we put forward the argument that there is substantive clinical and biological evidence to support a role for aberrant lipid metabolism and lipid mediators in the pathogenesis of PF.