Store-operated Ca(2+) entry is expressed in human endothelial progenitor cells.
Endothelial progenitor cells (EPCs) may be recruited from the bone marrow to sites of tissue regeneration to sustain neovascularization and reendothelialization after acute vascular injury. This feature makes them particularly suitable for cell-based therapy. In mature endothelium, store-operated Ca(2+) entry (SOCE) is activated following emptying of inositol-1,4,5-trisphosphate-sensitive stores, and controls a wide number of functions, including proliferation, nitric oxide synthesis, and vascular permeability. The present work aimed at investigating SOCE expression in EPCs harvested from both peripheral blood (PB-EPCs) and umbilical cord blood (UCB-EPCs) by employing both Ca(2+) imaging and molecular biology techniques. SOCE was induced upon either pharmacological (ie, cyclopiazonic acid) or physiological (ie, ATP) depletion of the intracellular Ca(2+) pool. Further, store-dependent Ca(2+) entry was inhibited by the SOCE inhibitor, N-(4-[3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl]phenyl)-4-methyl-1,2,3-thiadiazole-5-carboxamide (BTP-2). Real-time reverse transcription-polymerase chain reaction and western blot analyses showed that both PB-EPCs and UCB-EPCs express all the molecular candidates to mediate SOCE in differentiated cells, including TRPC1, TRPC4, Orai1, and Stim1. Moreover, pharmacological maneuvers demonstrated that, as well as in differentiated endothelial cells, the signal transduction pathway leading to depletion of the intracellular Ca(2+) pool impinged on the phospholipase C/inositol-1,4,5-trisphosphate pathway. Finally, blockage of SOCE with BTP-2 impaired PB-EPC proliferation. These findings provide the first evidence that EPCs express SOCE, which might thus be regarded as a novel target to enhance the regenerative outcome of cell-based therapy.
Sánchez-Hernández
Yuly
Y
Department of Physiology, University of Pavia, Pavia, Italy.
Laforenza
Umberto
U
Bonetti
Elisa
E
Fontana
Jacopo
J
Dragoni
Silvia
S
Russo
Marika
M
Avelino-Cruz
José Everardo
JE
Schinelli
Sergio
S
Testa
Domenico
D
Guerra
Germano
G
Rosti
Vittorio
V
Tanzi
Franco
F
Moccia
Francesco
F
D000813:Anilides / Q000378:metabolism / Q000494:pharmacology; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000235:genetics / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism*; D013830:Thiadiazoles / Q000378:metabolism / Q000494:pharmacology; D010738:Type C Phospholipases / Q000378:metabolism; D014470:Umbilical Cord / Q000166:cytology
C476308:4-methyl-4'-(3,5-bis(trifluoromethyl)-1H-pyrazol-1-yl)-1,2,3-thiadiazole-5-carboxanilide; D000813:Anilides; D015220:Calcium Channels; D013830:Thiadiazoles; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases; D002118:Calcium