[The effect of vascular endothelia growth factor encapsulated in nanoparticles on chronic limb ischemia].
OBJECTIVE
To experimentally investigate direct intramuscular gene transfer of nanoparticles encoding vascular endothelial growth factor for the treatment of peripheral artery disease.


METHODS
The human VEGF(165) cDNA was cloned into the eukaryotic expression vector PIRES2 under the control of cytomegalovirus promoter/enhancer. The recombinant gene was transferred into a rabbit model of chronic hindlimb ischemia by naked plasmid and nanoparticle respectively. Ischemia was induced in the hindlimb of New Zealand White rabbits by ligation of the distal external iliac artery and complete excision of the femoral artery and all its branches. At day 7 postoperation animals received VEGF(165) plasmid (10 intramuscular) or nanoparticle-VEGF(165) (8 intramuscular). With RT-PCR, immunohistochemistry analysis, and angiography, the expression and biological effects of VEGF(165) gene in experimental animals were investigated.


RESULTS
Two weeks after initiation of therapy, angiography showed that the transfer of VEGF(165) gene stimulated the formation of focal neovessels and established collateral circulation. The adductor muscle of ischemic limbs was histologically examined at day 14. Capillary density was increased among VEGF(165)-transfected rabbits, especially Nano-VEGF(165)-treated animals (Naked VEGF(165) plasmid = 50.18 per mm(2), Nano-VEGF(165) = 81.22 per mm(2), Control = 29.54 per mm(2), P < 0.05). RT-PCR showed that the transcription and expression of VEGF(165) gene in experimental group were significantly higher than those of control groups.


CONCLUSIONS
Intramuscular administration of VEGF(165) induces collateral artery augmentation in the rabbit model of chronic limb ischemia. Nanoparticle can act as a vector to transfect specific gene and it will benefit gene transfer.
Xu
Yi-yao
YY
Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences Peking United Medical College, Beijing 100730, China.
Li
Yong-jun
YJ
Guan
Heng
H
Liu
Chang-wei
CW
Zheng
Yue-hong
YH
Liu
Bao
B
Yang
Jing
J
Song
Cun-xian
CX
D000792:Angiography; D000818:Animals; D002214:Capsules; D002908:Chronic Disease; D004195:Disease Models, Animal; D015316:Genetic Therapy / Q000379:methods; D006614:Hindlimb / Q000098:blood supply; D007150:Immunohistochemistry; D007511:Ischemia / Q000235:genetics / Q000628:therapy*; D008297:Male; D036103:Nanotechnology; D010316:Particle Size; D011817:Rabbits; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000627:therapeutic use*
D002214:Capsules; D042461:Vascular Endothelial Growth Factor A