Background: Although intravenous administration of prostaglandin E(1) (PGE(1)) is commonly used in the treatment of peripheral arterial disease, it rapidly becomes inactivated in the lung. Whether local administration of sustained-release (SR) PGE(1) enhances neovascularization in murine hindlimb ischemia was investigated.
Methods and results: Poly lactide-co-glycolide (PLGA) microspheres were the 4-week SR carrier of PGE(1). C57BL/6 mice with unilateral hindlimb ischemia were randomly treated as follows: no treatment (Group N); single administration of 100 microg/kg PGE(1) solution (Group L) into the ischemic muscles; daily systemic administration of PGE(1) for 2 weeks at a total dose 100 microg/kg (Group S); and single administration of PGE(1)-100 microg/kg-loaded PLGA (Group P100) into the ischemic muscles. The blood perfusion in Group P100 was higher than in Groups N, L and S (ischemic/nonischemic blood perfusion ratio 88 +/-11% vs 73 +/-11% (P<0.01), 77 +/-9% (P<0.05), 79 +/-11% (P<0.05), respectively). Vascular density and alphaSMA-positive-vessel density in Group P100 were higher than in Groups N, L and S (vascular density (vessels/m(2)): 241 +/-39 vs 169 +/-49 (P<0.01), 169 +/-54 (P<0.01), 201 +/-42 (P<0.05), respectively; alphaSMA-positive-vessel density (vessels/m(2)): 34 +/-10 vs 18 +/-6 (P<0.01), 21 +/-11 (P<0.01), 22 +/-10 (P<0.01), respectively)
Conclusions: Local administration of a single dose of SR PGE(1) enhances neovascularization in mice hindlimb ischemia more efficiently than daily systemic administration.