title: Regulation of PGE(2) and PGI(2) release from human umbilical vein endothelial cells by actin cytoskeleton.
abstract: Disruption of microfilaments in human umbilical vein endothelial cells (HUVEC) with cytochalasin D (cytD) or latrunculin A (latA) resulted in a 3.3- to 5.7-fold increase in total synthesis of prostaglandin E(2) (PGE(2)) and a 3.4- to 6.5-fold increase in prostacyclin (PGI(2)) compared with control cells. Disruption of the microtubule network with nocodazole or colchicine increased synthesis of PGE(2) 1.7- to 1.9-fold and PGI(2) 1.9- to 2.0-fold compared with control cells. Interestingly, however, increased release of PGE(2) and PGI(2) from HUVEC into the media occurred only when microfilaments were disrupted. CytD treatment resulted in 6.7-fold more PGE(2) and 3.8-fold more PGI(2) released from HUVEC compared with control cells; latA treatment resulted in 17.7-fold more PGE(2) and 11.2-fold more PGI(2) released compared with control cells. Both increased synthesis and release of prostaglandins in response to all drug treatments were completely inhibited by NS-398, a specific inhibitor of cyclooxygenase-2 (COX-2). Disruption of either microfilaments using cytD or latA or of microtubules using nocodazole or colchicine resulted in a significant increase in COX-2 protein levels, suggesting that the increased synthesis of prostaglandins in response to drug treatments may result from increased activity of COX-2. These results, together with studies demonstrating a vasoprotective role for prostaglandins, suggest that the cytoskeleton plays an important role in maintenance of endothelial barrier function by regulating prostaglandin synthesis and release from HUVEC.
authors.affiliation: Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Sawyer
authors.forename: S M
authors.initials: SM
authors.lastname: Norvell
authors.forename: S M
authors.initials: SM
authors.lastname: Ponik
authors.forename: F M
authors.initials: FM
authors.lastname: Pavalko
mesh_terms: D000199:Actins / Q000502:physiology*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D003078:Colchicine / Q000494:pharmacology; D015638:Cytochalasin D / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D015232:Dinoprostone / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D011464:Epoprostenol / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008387:Marine Toxins / Q000494:pharmacology; D008870:Microtubules / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D015739:Nocodazole / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines; D014471:Umbilical Veins
chemical_list: D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D008387:Marine Toxins; D013844:Thiazoles; D053778:Thiazolidines; D015638:Cytochalasin D; D011464:Epoprostenol; D015232:Dinoprostone; D015739:Nocodazole; D003078:Colchicine; C037067:latrunculin A