The effects of the overexpression of recombinant uncoupling protein 2 on proliferation, migration and plasminogen activator inhibitor 1 expression in human vascular smooth muscle cells.
OBJECTIVE
Increased oxidative stress in vascular smooth muscle cells (VSMCs) has been implicated in the pathogenesis of accelerated atherosclerosis in patients with diabetes mellitus. Uncoupling protein 2 (UCP-2) is an important regulator of intracellular reactive oxygen species (ROS) production. We hypothesised that UCP-2 functions as an inhibitor of the atherosclerotic process in VSMCs.


METHODS
Overexpression of human UCP-2 was performed in primary cultured human VSMCs (HVSMCs) via adenovirus-mediated gene transfer. Its effects on ROS production, AP-1 activity, plasminogen activator inhibitor 1 (PAI-1) gene expression, and cellular proliferation and migration were measured in response to high glucose and angiotensin II (Ang II) concentrations, two major factors in the pathogenesis of atherosclerosis in patients with diabetes and hypertension. Mitochondrial membrane potential and NAD(P)H oxidase activity were also measured.


RESULTS
High glucose and Ang II caused transient mitochondrial membrane hyperpolarisation. They also significantly stimulated ROS production, NAD(P)H oxidase activity, mitochondrial membrane potential, AP-1 activity, PAI-1 mRNA expression, and proliferation and migration of HVSMCs. Adenovirus-mediated transfer of the UCP-2 gene reversed all of these effects.


CONCLUSIONS
The present study demonstrates that UCP-2 can modify atherosclerotic processes in HVSMCs in response to high glucose and Ang II. Our data suggest that agents increasing UCP-2 expression in vascular cells may help prevent the development and progression of atherosclerosis in patients with diabetes and hypertension.
Park
J-Y
JY
Department of Internal Medicine, College of Medicine, University of Ulsan, Poongnap-dong, Songpa-ku, Seoul 138-736, South Korea.
Park
K-G
KG
Kim
H-J
HJ
Kang
H-G
HG
Ahn
J D
JD
Kim
H-S
HS
Kim
Y M
YM
Son
S M
SM
Kim
I J
IJ
Kim
Y K
YK
Kim
C D
CD
Lee
K-U
KU
Lee
I-K
IK
D001013:Aorta, Thoracic; D001161:Arteriosclerosis / Q000517:prevention & control; D002455:Cell Division; D002465:Cell Movement; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007473:Ion Channels; D026901:Membrane Transport Proteins / Q000378:metabolism* / Q000494:pharmacology; D024101:Mitochondrial Proteins / Q000378:metabolism* / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D009924:Organ Culture Techniques; D017395:Plasminogen Activator Inhibitor 1 / Q000235:genetics*; D017382:Reactive Oxygen Species / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014019:Tissue Donors; D014162:Transfection; D000071246:Uncoupling Protein 2
D017931:DNA Primers; D018076:DNA, Complementary; D007473:Ion Channels; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D017395:Plasminogen Activator Inhibitor 1; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; C000604389:UCP2 protein, human; D000071246:Uncoupling Protein 2; D006861:Hydrogen Peroxide