title: Instant membrane resealing in nlrp3 inflammmasome activation of endothelial cells.
abstract: The present study explored the molecular mechanisms by which instant cell membrane resealing (CMR) controls the activation of NOD-like receptor pyrin domain containing 3 (Nlrp3) inflammasomes. Using wavelength-switching fluorescent microscopy with PI and fura-2 as indicators, we monitored instant CMR simultaneously with (Ca(2+))i in mouse microvascular endothelial cell (MVECs). LCWE or saponin wad found to produce membrane injury, which was resealed in a Ca(2+)-dependent manner, but abolished by FasL, a membrane raft (MR) clustering stimulator. Even in the presence of Ca(2+), FasL prolonged the CMR time as shown by an earlier onset of PI influx (48±12 sec vs. 17±3 min. of control). These effects of FasL were substantially blocked by an MR disruptor, methyl-beta-cyclodextrin (MCD). The failure of CMR upon FasL activated Nlrp3 inflammasomes, which was blocked by MCD, a membrane resealing compound, VA64 or siRNA of an MR-facilitating enzyme, acid sphingomyelinase. This inflammasome activation was due to increased lysosomal permeability and cathepsin B release. It is concluded that an MR-associated CMR protects ECs from Nlrp3 inflammasome activation induced by membrane injury.
authors.affiliation: Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, 1220 East Broad Street, Richmond, VA 23298, 2Department of Pharmacological & Pharmaceutical Sciences College of Pharmacy, University of Houston, 3605 Cullen B.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Ming
authors.initials: M
authors.lastname: Yuan
authors.forename: Min
authors.initials: M
authors.lastname: Xia
authors.affiliation: Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, 1220 East Broad Street, Richmond, VA 23298, 2Department of Pharmacological & Pharmaceutical Sciences College of Pharmacy, University of Houston, 3605 Cullen B, pli@vcu.edu.
authors.forename: Pin-Lan
authors.initials: PL
authors.lastname: Li
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism*; D002401:Cathepsin B / Q000378:metabolism; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D004789:Enzyme Activation; D005434:Flow Cytometry; D058847:Inflammasomes / Q000378:metabolism*; D051379:Mice; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein
chemical_list: D002352:Carrier Proteins; D058847:Inflammasomes; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein; C492716:Nlrp3 protein, mouse; D002401:Cathepsin B; D002118:Calcium