RRC ID |
197
|
Author |
Xu JW, Ikeda K, Kobayakawa A, Ikami T, Kayano Y, Mitani T, Yamori Y.
|
Title |
Downregulation of Rac1 activation by caffeic acid in aortic smooth muscle cells.
|
Journal |
Life Sci
|
Abstract |
Caffeic acid, a dietary phenol from coffee, fruits and vegetables, is an efficient antioxidant. However, little is known about its anti-oxidative mechanism in the modulation of fundamental cellular processes. In this study, we investigated whether caffeic acid regulates Rac1 GTPase activity, a partner of NADPH oxidase. Our results showed that caffeic acid decrease Rac1 protein level under basal conditions and incubation with angiotensin II (ANG II) in vascular smooth muscle cells. In a Rac-bound-to-PAK pull down assay, caffeic acid clearly inhibited Rac1 activity. We also observed that caffeic acid suppressed the generation of superoxide anion stimulated by ANG II that activates NADPH oxidase. On the other hand, co-incubation with caffei caid and cycloheximide significantly accelerated the Rac1 degradation. In addition, pretreatment with caffeic acid for 24 hours was able to prevent phosphorylation of MLC and HSP27, when cells were challenged with ANG II through the redox sensitive pathway. These results support the hypothesis that caffeic acid reduces Rac1 GTPase protein and activity level, followed by a down-regulation of NADPH oxidase activity.
|
Volume |
76(24)
|
Pages |
2861-72
|
Published |
2005-4-29
|
DOI |
10.1016/j.lfs.2004.11.015
|
PII |
S0024-3205(05)00073-1
|
PMID |
15808886
|
MeSH |
Analysis of Variance
Angiotensin II / metabolism
Animals
Antioxidants / pharmacology*
Aorta / cytology*
Blotting, Western
Caffeic Acids / pharmacology*
Cycloheximide / metabolism
Enzyme Activation / drug effects
HSP27 Heat-Shock Proteins
Heat-Shock Proteins / metabolism
Male
Muscle, Smooth, Vascular / cytology
Muscle, Smooth, Vascular / metabolism*
Neoplasm Proteins / metabolism
Phosphorylation / drug effects
Protein Serine-Threonine Kinases
Rats
Rats, Inbred WKY
Superoxides / metabolism
Transfection
p21-Activated Kinases
rac1 GTP-Binding Protein / metabolism*
|
IF |
3.647
|
Times Cited |
24
|
WOS Category
|
MEDICINE, RESEARCH & EXPERIMENTAL
PHARMACOLOGY & PHARMACY
|
Resource |
Rats |
SHRSP/Izm(strainID=409)
WKY/Izm(strainID=412) |