Extracellular vesicles released from p18 overexpressing pulmonary endothelial cells are barrier protective – potential implications for acute respiratory distress syndrome

Abstract

The novel endosome protein, p18, and the early endosome GTPase, Rab4, play a significant role in protecting the pulmonary vasculature against permeability associated with acute respiratory distress syndrome. Recently, endothelial-derived extracellular vesicles have been identified to play a key role in the endothelial permeability associated with acute respiratory distress syndrome. Therefore, we investigated the effect of these microparticles, released from endothelial cells overexpressing p18 and Rab4, on pulmonary endothelial barrier function. Endothelial-derived extracellular vesicles isolated from lung microvascular endothelial cells which overexpressed cDNA for wild-type p18 protected a naïve monolayer against lipopolysaccharide-induced permeability. In contrast, endothelial-derived extracellular vesicles from cells overexpressing the non-endosomal binding p18 mutant (p18N39) exerted no protective effect on the endothelial monolayer. Cells overexpressing either dominant active or inactive Rab4 released endothelial-derived extracellular vesicles which had no effect on lipopolysaccharide-induced permeability. miRNA analysis and permeability studies of endothelial-derived extracellular vesicle isolated from wild-type p18-overexpressing cells demonstrates that let-7i-5p, miR-96-5p, and miR-137-3p are endothelial-derived extracellular vesicle cargo which exert protective effects on the pulmonary endothelium. Finally, we observed down-regulation of p18 protein expression in both the lung and endothelium in an in vivo and in vitro model of acute respiratory distress syndrome. These results demonstrate that endothelial-derived extracellular vesicle released from cells overexpressing p18, but not Rab4, contain miRNA cargo which likely promote a barrier-protective effect on the pulmonary endothelium in settings of acute respiratory distress syndrome. Findings indicate the importance of p18 in the pulmonary vasculature and demonstrate that targeting this protein may provide a novel therapeutic strategy to reduce endothelial permeability associated with acute respiratory distress syndrome.

Dual Role of Extracellular Vesicles in Sepsis-Associated Kidney and Lung Injury

“…The expression profile of miRNAs in EVs from p18 overexpressing cells was different compared with controls. In fact, specific miRNAs (i.e., miR-30a-5p, miR-96-5p, and miR-137-5p) attenuated or even completely blocked (i.e., let-7i-5p) endothelial permeability after LPS challenge in vitro [ 121 ]. These findings suggest that given the pivotal role of endothelium as a first barrier involved after tissue injury, endothelium-derived EVs may work as biomarkers of ongoing damage.…”

Recent Advances in Molecular Diagnosis of Pulmonary Fibrosis for Precision Medicine

“…In the conditions of homeostasis and disease, most cells in the pulmonary system shed EVs into the extracellular spaces. While bronchial epithelial cells and macrophages are the main sources of EV production, injured lung epithelial cells subsequently release EVs that promote inflammation and fibrogenesis in acute respiratory distress syndrome (ARDS) and lung fibrosis. , Furthermore, endothelial cells, immune cells, and fibroblasts also secret EVs for pathological progression. − Recent studies have focused on identifying EV biomarkers in pulmonary fibrosis using various biofluids (Table ). ,,,− BALF is the most investigated biofluid in the pulmonary system as a noninvasive means to collect fluids after washing selected lobes with saline. ,,,,,, BALF contains relatively large amounts of biomolecules derived from pulmonary resident cells and thus shows better specificity than peripheral blood. , …”

lnc001776 Affects CPB2 Toxin-Induced Excessive Injury of Porcine Intestinal Epithelial Cells via Activating JNK/NF-kB Pathway through ssc-let-7i-5p/IL-6 Axis

“…For instance, Xiao et al [ 31 ] found that let-7i-5p expression was markedly decreased in cycling exosomes and rostral ventrolateral medulla (RVLM), and that let-7i-5p attenuated the inflammatory response in pheochromocytoma cells (PC12). Harrington et al [ 32 ] indicated that let-7i-5p was a carrier of endothelium-derived extracellular vesicles and was protective of the LPS-treated lung endothelial cell barrier. However, the potential mechanism of let-7i-5p in CpC -infected piglet diarrhea and intestinal inflammation needs further investigation.…”