title: Glycolysis and oxidative phosphorylation are essential for purinergic receptor-mediated angiogenic responses in vasa vasorum endothelial cells.
abstract: Angiogenesis is an energy-demanding process; however, the role of cellular energy pathways and their regulation by extracellular stimuli, especially extracellular nucleotides, remain largely unexplored. Using metabolic inhibitors of glycolysis (2-deoxyglucose) and oxidative phosphorylation (OXPHOS) (oligomycin, rotenone, and FCCP), we demonstrate that glycolysis and OXPHOS are both essential for angiogenic responses of vasa vasorum endothelial cell (VVEC). Treatment with P2R agonists, ATP, and 2-methylthioadenosine diphosphate trisodium salt (MeSADP), but not P1 receptor agonist, adenosine, increased glycolytic activity in VVEC (measured by extracellular acidification rate and lactate production). Stimulation of glycolysis was accompanied by increased levels of phospho-phosphofructokinase B3, hexokinase (HK), and GLUT-1, but not lactate dehydrogenase. Moreover, extracellular ATP and MeSADP, and to a lesser extent adenosine, increased basal and maximal oxygen consumption rates in VVEC. These effects were potentiated when the cells were cultured in 20 mM galactose and 5 mM glucose compared with 25 mM glucose. Treatment with P2R agonists decreased phosphorylation of pyruvate dehydrogenase (PDH)-E1α and increased succinate dehydrogenase (SDH), cytochrome oxidase IV, and β-subunit of F1F0ATP synthase expression. In addition, P2R stimulation transiently elevated mitochondrial Ca2+concentration, implying involvement of mitochondria in VVEC angiogenic activation. We also demonstrated a critical role of phosphatidylinositol 3-kinase and Akt pathways in lactate production, PDH-E1α phosphorylation, and the expression of HK, SDH, and GLUT-1 in ATP-stimulated VVEC. Together, our findings suggest that purinergic and metabolic regulation of VVEC energy pathways is essential for VV angiogenesis and may contribute to pathologic vascular remodeling in pulmonary hypertension.
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado.
authors.forename: Martin
authors.initials: M
authors.lastname: Lapel
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado.
authors.forename: Philip
authors.initials: P
authors.lastname: Weston
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado.
authors.forename: Derek
authors.initials: D
authors.lastname: Strassheim
authors.affiliation: Department of Medicine, University of Colorado Denver, Aurora, Colorado; and.
authors.forename: Vijaya
authors.initials: V
authors.lastname: Karoor
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado.
authors.forename: Nana
authors.initials: N
authors.lastname: Burns
authors.affiliation: Department of Medicine, University of Colorado Denver, Aurora, Colorado; and.
authors.forename: Taras
authors.initials: T
authors.lastname: Lyubchenko
authors.affiliation: Department of Pharmacology, University of Colorado Denver, Aurora, Colorado.
authors.forename: Petr
authors.initials: P
authors.lastname: Paucek
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado.
authors.forename: Kurt R
authors.initials: KR
authors.lastname: Stenmark
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Aurora, Colorado; evgenia.gerasimovskaya@ucdenver.edu.
authors.forename: Evgenia V
authors.initials: EV
authors.lastname: Gerasimovskaya
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology*; D006019:Glycolysis / Q000502:physiology*; D008297:Male; D018919:Neovascularization, Physiologic / Q000502:physiology*; D010085:Oxidative Phosphorylation; D011983:Receptors, Purinergic; D014651:Vasa Vasorum / Q000166:cytology* / Q000502:physiology*
chemical_list: D011983:Receptors, Purinergic
keywords: OXPHOS; angiogenesis; cellular metabolism; endothelial cells; glycolysis; purinergic receptors; vasa vasorum