Abstract
Photochemical reactions used in photodynamic therapy are reported to damage normal cells and tissues in ways that increase endothelial permeability and thereby cause excessive neointimal formation and subsequent restenosis. To investigate the mechanisms of this permeability increase in vitro, human umbilical vein endothelial cells were incubated with the porphyrin precursor δ-aminolevulinic acid and then irradiated with a 646 nm light-emitting diode (LED). Results using Transwells® supports showed that the photochemical reaction increased endothelial permeability by 200%, and fluorescence microscopy revealed that destruction of the capillary-like structures due to cell shrinkage was accompanied by VE-cadherin mislocalization and stress fiber formation. The generated gaps between cells were observed using dyed β1-integrin and total internal reflection fluorescence microscopy. Western blotting indicated that the photochemical reaction phosphorylated GDP-RhoA to GTP-RhoA, a protein that promotes stress fiber formation and inhibits VE-cadherin production. When forskolin/rolipram or 8CPT-2′O-Me- cAMP, both of which inhibit further reaction of phosphorylated RhoA, were added, no formation of stress fibers or mislocalization of VE-cadherin was observed, thus preventing an increase in endothelial permeability. Taken together, photochemically induced RhoA activation appears to play a key role in increasing endothelial permeability during changes in morphology of endothelial cells.
| Original language | English |
|---|---|
| Pages (from-to) | 1401-1407 |
| Number of pages | 7 |
| Journal | Photochemical and Photobiological Sciences |
| Volume | 8 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 2009 |
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ASJC Scopus subject areas
- Physical and Theoretical Chemistry
Cite this
Photochemically induced increase in endothelial permeablity regulated by RhoA activation. / Ota, Hiroki; Matsumura, Mimiko; Miki, Norihisa; Minamitami, Haruyuki.
In: Photochemical and Photobiological Sciences, Vol. 8, No. 10, 2009, p. 1401-1407.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Photochemically induced increase in endothelial permeablity regulated by RhoA activation
AU - Ota, Hiroki
AU - Matsumura, Mimiko
AU - Miki, Norihisa
AU - Minamitami, Haruyuki
PY - 2009
Y1 - 2009
N2 - Photochemical reactions used in photodynamic therapy are reported to damage normal cells and tissues in ways that increase endothelial permeability and thereby cause excessive neointimal formation and subsequent restenosis. To investigate the mechanisms of this permeability increase in vitro, human umbilical vein endothelial cells were incubated with the porphyrin precursor δ-aminolevulinic acid and then irradiated with a 646 nm light-emitting diode (LED). Results using Transwells® supports showed that the photochemical reaction increased endothelial permeability by 200%, and fluorescence microscopy revealed that destruction of the capillary-like structures due to cell shrinkage was accompanied by VE-cadherin mislocalization and stress fiber formation. The generated gaps between cells were observed using dyed β1-integrin and total internal reflection fluorescence microscopy. Western blotting indicated that the photochemical reaction phosphorylated GDP-RhoA to GTP-RhoA, a protein that promotes stress fiber formation and inhibits VE-cadherin production. When forskolin/rolipram or 8CPT-2′O-Me- cAMP, both of which inhibit further reaction of phosphorylated RhoA, were added, no formation of stress fibers or mislocalization of VE-cadherin was observed, thus preventing an increase in endothelial permeability. Taken together, photochemically induced RhoA activation appears to play a key role in increasing endothelial permeability during changes in morphology of endothelial cells.
AB - Photochemical reactions used in photodynamic therapy are reported to damage normal cells and tissues in ways that increase endothelial permeability and thereby cause excessive neointimal formation and subsequent restenosis. To investigate the mechanisms of this permeability increase in vitro, human umbilical vein endothelial cells were incubated with the porphyrin precursor δ-aminolevulinic acid and then irradiated with a 646 nm light-emitting diode (LED). Results using Transwells® supports showed that the photochemical reaction increased endothelial permeability by 200%, and fluorescence microscopy revealed that destruction of the capillary-like structures due to cell shrinkage was accompanied by VE-cadherin mislocalization and stress fiber formation. The generated gaps between cells were observed using dyed β1-integrin and total internal reflection fluorescence microscopy. Western blotting indicated that the photochemical reaction phosphorylated GDP-RhoA to GTP-RhoA, a protein that promotes stress fiber formation and inhibits VE-cadherin production. When forskolin/rolipram or 8CPT-2′O-Me- cAMP, both of which inhibit further reaction of phosphorylated RhoA, were added, no formation of stress fibers or mislocalization of VE-cadherin was observed, thus preventing an increase in endothelial permeability. Taken together, photochemically induced RhoA activation appears to play a key role in increasing endothelial permeability during changes in morphology of endothelial cells.
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U2 - 10.1039/b906028f
DO - 10.1039/b906028f
M3 - Article
VL - 8
SP - 1401
EP - 1407
JO - Photochemical and Photobiological Sciences
JF - Photochemical and Photobiological Sciences
SN - 1474-905X
IS - 10
ER -