Role of matrix metaloproteases in idiopathic pulmonary fibrosis

Lung fibrosis is the final common pathway of a large variety of chronic lung disorders, named interstitial lung diseases. The most aggressive form is the idiopathic pulmonary fibrosis [IPF] characterized by alveolar epithelial cell injury/activation, expansion of the fibroblast/myofibroblast population, and the exaggerated accumulation of extracellular matrix [ECM] components which ultimately result in the destruction of the lung parenchyma. Several matrix metalloproteases [MMPs] are upregulated in the IPF lungs and have been shown to actively participate in the pathogenesis of the disease through extracellular matrix remodeling and basement membrane disruption. However, MMPs can also breakdown molecules that mediate cell-cell and cell-ECM interactions, and can activate growth factors and growth factor receptors indicating that they likely contribute to other local biopathological processes such as apoptosis, migration, proliferation and angiogenesis.