title: Heme oxygenase and angiogenic activity of endothelial cells: stimulation by carbon monoxide and inhibition by tin protoporphyrin-IX.
abstract: The activity of heme oxygenase enzymes (HOs) is responsible for the endogenous source of carbon monoxide (CO). Their activities can be inhibited by tin protoporphyrin-IX (SnPPIX). Recent data indicate the involvement of HOs in the regulation of angiogenesis. Here, we investigated the role of the HO pathway in the production and angiogenic activity of vascular endothelial growth factor (VEGF) in endothelial cells treated with SnPPIX, or cultured in the presence of a CO-releasing molecule (CO-RM). Addition of CO-RM or induction of HO-1 by hemin resulted in a threefold elevation in CO production in culture medium (up to 20.3 microg/L) and was associated with a 30% increase in VEGF synthesis. Much higher levels of CO (up to 60 microg/L) and a further increase in VEGF production (by 277%) were measured in cells treated with prostaglandin-J(2), a potent activator of HO-1. SnPPIX prevented the induction of CO generation and inhibited VEGF synthesis. Moreover, SnPPIX reduced the VEGF-elicited angiogenic activities of endothelial cells by decreasing their proliferation (by 26%), migration (by 46%), formation of tubes on Matrigel (by 48%), and outgrowth of capillaries from endothelial spheroids (by 30%). In contrast, overexpression of HO-1 or incubation of cells with CO-RM led to an increase in capillary sprouting. Thus, HO activity up-regulates VEGF production and augments the capability of endothelial cells to respond to exogenous stimulation.
authors.affiliation: Department of Vascular Surgery, University of Vienna, Austria. alicia@mol.uj.edu.pl
authors.forename: Alicja
authors.initials: A
authors.lastname: Józkowicz
authors.forename: Ihor
authors.initials: I
authors.lastname: Huk
authors.forename: Anneliese
authors.initials: A
authors.lastname: Nigisch
authors.forename: Guenter
authors.initials: G
authors.lastname: Weigel
authors.forename: Wolf
authors.initials: W
authors.lastname: Dietrich
authors.forename: Roberto
authors.initials: R
authors.lastname: Motterlini
authors.forename: Józef
authors.initials: J
authors.lastname: Dulak
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D002196:Capillaries / Q000378:metabolism; D002248:Carbon Monoxide / Q000378:metabolism*; D002455:Cell Division; D002460:Cell Line; D002465:Cell Movement; D002470:Cell Survival; D002478:Cells, Cultured; D003094:Collagen / Q000494:pharmacology; D003470:Culture Media / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D004338:Drug Combinations; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006419:Heme Oxygenase (Decyclizing) / Q000378:metabolism*; D006427:Hemin / Q000378:metabolism; D006801:Humans; D007797:Laminin / Q000494:pharmacology; D008665:Metalloporphyrins / Q000494:pharmacology*; D018919:Neovascularization, Physiologic; D011509:Proteoglycans / Q000494:pharmacology; D011524:Protoporphyrins / Q000494:pharmacology*; D051381:Rats; D013997:Time Factors; D014162:Transfection; D014471:Umbilical Veins / Q000166:cytology; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D003470:Culture Media; D004338:Drug Combinations; D004791:Enzyme Inhibitors; D007797:Laminin; D008665:Metalloporphyrins; D011509:Proteoglycans; D011524:Protoporphyrins; D042461:Vascular Endothelial Growth Factor A; C059485:matrigel; D006427:Hemin; D002248:Carbon Monoxide; D003094:Collagen; C032628:tin protoporphyrin IX; D006419:Heme Oxygenase (Decyclizing); D006152:Cyclic GMP