Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin-induced
barrier breakdown
Y. Baumer, V. Spindler, R. Werthmann, M. Bunemann, und J. Waschke. J Cell Physiol, 220 (3):
716-26(September 2009)Baumer, Y Spindler, V Werthmann, R C Bunemann, M Waschke, J Research
Support, Non-U.S. Gov't United States Journal of cellular physiology
J Cell Physiol. 2009 Sep;220(3):716-26..
Zusammenfassung
Barrier stabilizing effects of cAMP as well as of the small GTPase
Rac 1 are well established. Moreover, it is generally believed that
permeability-increasing mediators such as thrombin disrupt endothelial
barrier functions primarily via activation of Rho A. In this study,
we provide evidence that decrease of both cAMP levels and of Rac
1 activity contribute to thrombin-mediated barrier breakdown. Treatment
of human dermal microvascular endothelial cells (HDMEC) with Rac
1-inhibitor NSC-23766 decreased transendothelial electrical resistance
(TER) and caused intercellular gap formation. These effects were
reversed by addition of forskolin/rolipram (F/R) to increase intracellular
cAMP but not by the cAMP analogue 8-pCPT-2'-O-Methyl-cAMP (O-Me-cAMP)
which primarily stimulates protein kinase A (PKA)-independent signaling
via Epac/Rap 1. However, both F/R and O-Me-cAMP did not increase
TER above control levels in the presence of NSC-23766 in contrast
to experiments without Rac 1 inhibition. Because Rac 1 was required
for maintenance of barrier functions as well as for cAMP-mediated
barrier stabilization, we tested the role of Rac 1 and cAMP in thrombin-induced
barrier breakdown. Thrombin-induced drop of TER and intercellular
gap formation were paralleled by a rapid decrease of cAMP as revealed
by fluorescence resonance energy transfer (FRET). The efficacy of
F/R or O-Me-cAMP to block barrier-destabilizing effects of thrombin
was comparable to Y27632-induced inhibition of Rho kinase but was
blunted when Rac 1 was inactivated by NSC-23766. Taken together,
these data indicate that decrease of cAMP and Rac 1 activity may
be an important step in inflammatory barrier disruption.
Baumer, Y Spindler, V Werthmann, R C Bunemann, M Waschke, J Research
Support, Non-U.S. Gov't United States Journal of cellular physiology
J Cell Physiol. 2009 Sep;220(3):716-26.
%0 Journal Article
%1 Baumer2009
%A Baumer, Y.
%A Spindler, V.
%A Werthmann, R. C.
%A Bunemann, M.
%A Waschke, J.
%D 2009
%J J Cell Physiol
%K *Signal AMP/analogs Activators/pharmacology Aminoquinolines/pharmacology Antigens, Biosensing CD/metabolism Cadherins/metabolism Calcium/metabolism Capillary Cells/drug Cultured Cyclic Electric Endothelial Energy Enzyme Factors Fluorescence Forskolin/pharmacology GTP-Binding Gap Humans Impedance Inhibitors/pharmacology Junctions/drug Microscopy, Permeability/drug Protein/antagonists Protein/metabolism Pyrimidines/pharmacology Resonance Rolipram/pharmacology Techniques Thrombin/*metabolism Time Transduction/drug Transfer cdc42 derivatives/*metabolism/pharmacology effects effects/*enzymology inhibitors/*metabolism rac1 Cell
%N 3
%P 716-26
%T Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin-induced
barrier breakdown
%U http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19472214
%V 220
%X Barrier stabilizing effects of cAMP as well as of the small GTPase
Rac 1 are well established. Moreover, it is generally believed that
permeability-increasing mediators such as thrombin disrupt endothelial
barrier functions primarily via activation of Rho A. In this study,
we provide evidence that decrease of both cAMP levels and of Rac
1 activity contribute to thrombin-mediated barrier breakdown. Treatment
of human dermal microvascular endothelial cells (HDMEC) with Rac
1-inhibitor NSC-23766 decreased transendothelial electrical resistance
(TER) and caused intercellular gap formation. These effects were
reversed by addition of forskolin/rolipram (F/R) to increase intracellular
cAMP but not by the cAMP analogue 8-pCPT-2'-O-Methyl-cAMP (O-Me-cAMP)
which primarily stimulates protein kinase A (PKA)-independent signaling
via Epac/Rap 1. However, both F/R and O-Me-cAMP did not increase
TER above control levels in the presence of NSC-23766 in contrast
to experiments without Rac 1 inhibition. Because Rac 1 was required
for maintenance of barrier functions as well as for cAMP-mediated
barrier stabilization, we tested the role of Rac 1 and cAMP in thrombin-induced
barrier breakdown. Thrombin-induced drop of TER and intercellular
gap formation were paralleled by a rapid decrease of cAMP as revealed
by fluorescence resonance energy transfer (FRET). The efficacy of
F/R or O-Me-cAMP to block barrier-destabilizing effects of thrombin
was comparable to Y27632-induced inhibition of Rho kinase but was
blunted when Rac 1 was inactivated by NSC-23766. Taken together,
these data indicate that decrease of cAMP and Rac 1 activity may
be an important step in inflammatory barrier disruption.
@article{Baumer2009,
abstract = {Barrier stabilizing effects of cAMP as well as of the small GTPase
Rac 1 are well established. Moreover, it is generally believed that
permeability-increasing mediators such as thrombin disrupt endothelial
barrier functions primarily via activation of Rho A. In this study,
we provide evidence that decrease of both cAMP levels and of Rac
1 activity contribute to thrombin-mediated barrier breakdown. Treatment
of human dermal microvascular endothelial cells (HDMEC) with Rac
1-inhibitor NSC-23766 decreased transendothelial electrical resistance
(TER) and caused intercellular gap formation. These effects were
reversed by addition of forskolin/rolipram (F/R) to increase intracellular
cAMP but not by the cAMP analogue 8-pCPT-2'-O-Methyl-cAMP (O-Me-cAMP)
which primarily stimulates protein kinase A (PKA)-independent signaling
via Epac/Rap 1. However, both F/R and O-Me-cAMP did not increase
TER above control levels in the presence of NSC-23766 in contrast
to experiments without Rac 1 inhibition. Because Rac 1 was required
for maintenance of barrier functions as well as for cAMP-mediated
barrier stabilization, we tested the role of Rac 1 and cAMP in thrombin-induced
barrier breakdown. Thrombin-induced drop of TER and intercellular
gap formation were paralleled by a rapid decrease of cAMP as revealed
by fluorescence resonance energy transfer (FRET). The efficacy of
F/R or O-Me-cAMP to block barrier-destabilizing effects of thrombin
was comparable to Y27632-induced inhibition of Rho kinase but was
blunted when Rac 1 was inactivated by NSC-23766. Taken together,
these data indicate that decrease of cAMP and Rac 1 activity may
be an important step in inflammatory barrier disruption.},
added-at = {2010-12-14T18:12:02.000+0100},
author = {Baumer, Y. and Spindler, V. and Werthmann, R. C. and Bunemann, M. and Waschke, J.},
biburl = {https://www.bibsonomy.org/bibtex/262715cb8eb5d5c44c0c87bc755142347/pharmawuerz},
endnotereftype = {Journal Article},
groups = {private},
interhash = {0eb6bd184789c3b2f12b4662dabddb4b},
intrahash = {62715cb8eb5d5c44c0c87bc755142347},
issn = {1097-4652 (Electronic) 1097-4652 (Linking)},
journal = {J Cell Physiol},
keywords = {*Signal AMP/analogs Activators/pharmacology Aminoquinolines/pharmacology Antigens, Biosensing CD/metabolism Cadherins/metabolism Calcium/metabolism Capillary Cells/drug Cultured Cyclic Electric Endothelial Energy Enzyme Factors Fluorescence Forskolin/pharmacology GTP-Binding Gap Humans Impedance Inhibitors/pharmacology Junctions/drug Microscopy, Permeability/drug Protein/antagonists Protein/metabolism Pyrimidines/pharmacology Resonance Rolipram/pharmacology Techniques Thrombin/*metabolism Time Transduction/drug Transfer cdc42 derivatives/*metabolism/pharmacology effects effects/*enzymology inhibitors/*metabolism rac1 Cell},
month = Sep,
note = {Baumer, Y Spindler, V Werthmann, R C Bunemann, M Waschke, J Research
Support, Non-U.S. Gov't United States Journal of cellular physiology
J Cell Physiol. 2009 Sep;220(3):716-26.},
number = 3,
pages = {716-26},
shorttitle = {Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin-induced
barrier breakdown},
timestamp = {2010-12-14T18:20:48.000+0100},
title = {Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin-induced
barrier breakdown},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=19472214},
volume = 220,
year = 2009
}