Inhibition of Neointima Formation and Migration of Vascular Smooth Muscle Cells by Anti-vascular Endothelial Growth Factor Receptor-1 (Flt-1) Peptide in Diabetic Rats / 대한흉부외과학회지

ABSTRACT

BACKGROUND: Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis, including stimulating the proliferation and migration of vascular smooth muscle cells (VSMCs). It has been known that diabetes is associated with accelerated cellular proliferation via VEGF, as compared to that under a normal glucose concentration. We investigated the effects of selective blockade of a VEGF receptor by using anti-Flt-1 peptide on the formation and hyperplasia of the neointima in balloon injured-carotid arteries of OLETF rats and also on the in vitro VSMCs' migration under high glucose conditions. MATERIAL AND METHOD: The balloon-injury method was employed to induce neointima formation by VEGF. For 14 days beginning 2 days before the ballon injury, placebo or vascular endothelial growth factor receptor-1 (VEGFR-1) specific peptide (anti-Flt-1 peptide), was injected at a dose of 0.5 mg/kg daily into the OLETF rats. At 14 days after balloon injury, the neointimal proliferation and vascular luminal stenosis were measured, and cellular proliferation was assessed by counting the proliferative cell nuclear antigen (PCNA) stained cells. To analyze the effect of VEGF and anti-Flt-1 peptide on the migration of VSMCs under a high glucose condition, transwell assay with a matrigel filter was performed. And finally, to determine the underlying mechanism of the effect of anti-Flt-1 peptide on the VEGF-induced VSMC migration in vitro, the expression of matrix metalloproteinase (MMP) was observed by performing reverse transcription-polymerase chain reaction (RT-PCR). RESULT: Both the neointimal area and luminal stenosis associated with neointimal proliferation were significantly decreased in the anti-Flt-1 peptide injected rats, (0.15+/-0.04 mm2 and 36.03+/-3.78% compared to 0.24+/-0.03 mm2 and 61.85+/-5.11%, respectively, in the placebo-injected rats (p<0.01, respectively). The ratio of PCNA(+) cells to the entire neointimal cells was also significantly decreased from 52.82+/-4.20% to 38.11+/-6.89% by the injected anti-Flt-1 peptide (p<0.05). On the VSMC migration assay, anti-Flt-1 peptide significantly reduced the VEGF-induced VMSC migration by about 40% (p<0.01). Consistent with the effect of anti-Flt-1 peptide on VSMC migration, it also obviously attenuated the induction of the MMP-3 and MMP-9 mRNA expressions via VEGF in the VSMCs. CONCLUSION: Anti-Flt-1 peptide inhibits the formation and hyperplasia of the neointima in a balloon-injured carotid artery model of OLETF rats. Anti-Flt-1 peptide also inhibits the VSMCs' migration and the expressions of MMP-3 and MMP-9 mRNA induced by VEGF under a high glucose condition.