The role of proteoglycans in pulmonaryedema development

摘要: Pulmonary gas exchange critically depends upon the hydration state and thinness of interstitial tissue layer within alveolo-capillary membrane. In interstitium, fluid freely moving fibrous extracellular matrix (ECM) equilibrates with water chemically bound to hyaluronic acid proteoglycans (PGs). The dynamic equilibrium between these two phases is set maintained by transendothelial solutes exchanges, convective outflows into lymphatic system, mechanical hydrophilic properties solid elements ECM. ECM components, in particular chondroitin sulfate proteoglycan (CS-PG) heparan-sulfate (HS-PG) families, play a major role maintenance homeostasis. fact, they provide: (a) perivascular highly restrictive sieve respect plasma proteins, thus modulating both protein concentration filtration; (b) support vessels sustaining their draining function, (c) rigid three-dimensional low-compliant scaffold opposing accumulation space. Fragmentation PG induced increased volume, degradation through proteolytic or inflammatory agents, exposure inspiratory mixture modified oxygen fraction, strain/stress invariably results progressive loosening intermolecular bonds other components. loss PGs regulatory functions compromises protective progressively leading eventually severe lung edema.