Tumstatin (69-88) – Other Categories

Tumstatin is an anti-angiogenic matrikine fragment of collagen IV alpha3 subunit and a VEGF antagonist. Matrikines are bioactive extra cellular matrix (ECM) fragments which regulate cellular metabolism and influence ECM deposition and degradation. Airways of people with asthma have an 18-fold reduction in the levels tumstatin in their airway walls. Tumstatin reverses airway inflammation and remodelling in animal models of asthma in a mechanism involving autocrine remodelling of the ECM. The ECM regulates many aspects of cell biology including gene expression and inflammatory pathways. The airways ECM in asthma has been implicated in airway hyper-responsiveness (AHR), airway thickening, chronic inflammation and increased angiogenesis. Tumstatin fosters an anti-inflammatory and anti-angiogenic microenvironment which inhibits neutrophils in the airway tissue by modifying airway smooth muscle (ASM)-derived ECM. Tumstatin is present in endothelial cells, airway epithelial cells and primary lung fibroblasts, but not in primary ASM cells.