| Objective: Conventional therapy of ischemic heartdisease such as percutaneous coronary angioplasty and bypasssurgery can only treat epicardial blood vessels more than 2mm in diameter ideally. With discovery of several angiogensthat have been shown to promote revascularization in ischemictissues, a new strategy that may remedy the defect istherapeutic angiogenesis, the induction of new blood vesselsdevelopment-into area with limited blood flow. Among which,vascular endothelial growth factor A (VEGF-A), a potentialspecific endothelial cell (EC) mitogen, will be the mostpromise candidate which can not only promote the division,proliferation and migration of ECs, but also play a importantrole in the maturing and remodeling of blood vessels. Besidesefficacy, gene therapy is concerned with transfer efficacy ofvector and the safety of vector and gene, so clinically, it'sof great importance to study the efficacy and safety at thesame time. This study was designed to investigate whetheradenovirus (Ad) vector encoding VEGF165 cDNA (Ad-VEGF165)could induce angiogenesis and was safe or not.Methods: New Zealand White rabbits underwent ligationof femoral artery and injection of Ad-VEGF165 orphosphate-buffered saline solution (PBS, 0. 1M, PH7. 4) into theischemic thigh muscles. Enzyme-linked immunoassay (ELISA) wascarried out to invest igate the concentration of VEGFl65protein in musc1es. Three weeks after miniature swineunderwent 1eft thoracotomy and placement of an Ameroi dconstrictor on the left circumflex coronary artery (LCX),Ad--VEGF165 (n=6) or the contro1, Ad expressing D -galactosidase cDNA (Ad--Ga1, n=6), was admin istered direct lyinto the ischemic myocardium in the circumflex di stribution.Al1 the animals were sacrificed four weeks after secondsurgery. Myocardial perfusion and function were assessed bye 1ectrocardiogram--gated s ing1 e photon emi ss ion computedtomography (SPECT) imaging and ex vivo coronary angiography(CAG) was performed to examine co1lateral vessel s. Thevascular density and VEGF--positive cel ls were examined byimmunohistochemistry. Toxicity was assessed by blood ana1yseson the day before (day 0) and on day 1, 3, 7, 28 after yectorde1 ivery and by vascular, myocardial and l iver hi stology aftersacr if i ce.'Resu1ts: The peak expression of Ad--VEGF165 occurred 24hours after the administration of Ad--YEGF165 and decreasedgradua11y to contro1 level on day 7. The in vivo coronaryangiography demonstrated that the stenosi s of LCX was morethan 98%. Myocard ial SPECT imaging demonstrated no di fferencein ischemic area, rest ischemic severity, left Yentriculareject ion fraction and regional wal l motion between the controlgroup and the treated one before administrat ion of Ad--VEGF165.But 4 'eeks after administration of Ad--VEGF165, the stressmyocardial ischemic area reduced 65. 0% (Pr 0. 01) and 63. 2% (Pwt 0. 01), rest ischemic area 97. 4% (Pr 0. 01) and 97. 3% (Prt0. 01), rest ischemic severity 60. 1% (Pwt0. 01) and 61. 2% (Pwt 0. 01), while the left ventricular ejection fraction-increased 27. 6% (Pwt 0. 01) and 36. 6% (P< 0. 01), the grade ofregional 'all motion 2. 8 (P<0. 05) and 2. 6 (P< 0. 05) comparedwith that of Ad--Gal and before administration of Ad--VEGF165respect ively. Using the grading method of Rentrop, Col1ateralgrade for LCX and obtuse margina1 coronary artery assessed byangiography was 2. 6 greater in the Ad--VEGF165 anima1s than inthe Ad--gal (P rt 0. 05). The b1ood vesse1s measured byimmunohi stochemi stry was s igni fi cant ly greater in Ad--VEGF 165animals than in Ad--Gal anima1s (l0. 8f3. 8 vs 2. 9l0. 3, Pwt0. 01). Genera1 safety parameters inc1uding routine bloodparameters, l iver and kidney function and cardiac specificparameters demonstrated no di fference between Ad--VEGF165animals and Ad--Gal ones except for the red b1ood cell counton day 28 [ (7. 2f0. 9) X 10"/L vs (5. 9t0. 7...
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