Regulation and Repair of the Alveolar-Capillary Barrier in Acute Lung Injury

Abstract

Considerable progress has been made in understanding the basic mechanisms that regulate fluid and protein exchange across the endothelial and epithelial barriers of the lung under both normal and pathological conditions. Clinically relevant lung injury occurs most commonly from severe viral and bacterial infections, aspiration syndromes, and severe shock. The mechanisms of lung injury have been identified in both experimental and clinical studies. Recovery from lung injury requires the reestablishment of an intact endothelial barrier and a functional alveolar epithelial barrier capable of secreting surfactant and removing alveolar edema fluid. Repair mechanisms include the participation of endogenous progenitor cells in strategically located niches in the lung. Novel treatment strategies include the possibility of cell-based therapy that may reduce the severity of lung injury and enhance lung repair.

Myricetin Attenuates LPS-induced Inflammation in RAW 264.7 Macrophages and Mouse Models

“…On this basis, we think it was a possible candidate for treating ALI. Accumulated experiments proved that over-activated inflammatory cells in alveoli mediated the damages of epithelium and vascular endothelium which resulted in barrier dysfunction and the increase in vascular permeability as well as pulmonary edema finally (Bhattacharya and Matthay, 2013;Kim et al, 2017). The lung epithelium barrier integrity of the mice was tested according to the Evans blue dye extravasation assay to reveal the alveolar epithelial completeness.…”

Mesenchymal stem cells: mechanisms of potential therapeutic benefit in ARDS and sepsis

“…Vascular endothelial injury is a defi ning characteristic of both ARDS 59 and sepsis. 53 MSC therapy might help preserve endothelial barrier function in both syndromes (fi gure).…”

“…Alveolar epithelial cell injury contributes to several injury pathways in the development of ARDS, including loss of alveolar-capillary barrier integrity, dysregulated vectorial transport of alveolar fl uid, and disordered surfactant production. 59 MSCs might have a role in the preservation of epithelial cell function in ARDS.…”

Fasudil Attenuates LPS-Induced Acute Lung Injury by Preventing Endothelial Dysfunction

“…It is now well recognized that loss of endothelial cell-cell adhesion is sufficient to induce the formation of inter-endothelial cell gap which provide paracellular pathway for free passage of macromolecules through the endothelial barrier [30,31]. Several types of cellular junctions, such as tight junctions (TJs), adherens junctions (AJs) and gap junctions, participate in inter-endothelial adhesion.…”