Improved vascular survival and growth in the mouse model of hindlimb ischemia by a remote signaling mechanism.
Deficiencies in prolyl hydroxylase domain proteins (PHDs) may lead to the accumulation of hypoxia-inducible factor-α proteins, the latter of which activate local angiogenic responses by paracrine mechanisms. Here, we investigate whether a keratinocyte-specific PHD deficiency may promote vascular survival and growth in a distantly located ischemic tissue by a remote signaling mechanism. We generated mice that carry a keratinocyte-specific Phd2 knockout (kPhd2KO) and performed femoral artery ligation. Relative to wild-type controls, kPhd2KO mice displayed improved vascular survival and arteriogenesis in ischemic hind limbs, leading to the accelerated recovery of hindlimb perfusion and superior muscle regeneration. Similar protective effects were also seen in type 1 and type 2 diabetic mice. Molecularly, both abundance of hypoxia-inducible factor-1α protein and expression of vascular endothelial growth factor-A were increased in epidermal tissues of kPhd2KO mice, accompanied by increased plasma concentration of vascular endothelial growth factor-A. Contrary to kPhd2KO mice, which are PHD2 deficient in all skin tissues, localized kPhd2KO in hindlimb skin tissues did not have similar effects, excluding paracrine signaling as a major mechanism. Confirming the existence of remote effects, hepatocyte-specific Phd2 knockout also protected hind limbs from ischemia injury. These data indicate that vascular survival and growth in ischemia-injured tissue may be stimulated by suppressing PHD2 in a remotely located tissue and may provide highly effective angiogenesis therapies without the need for directly accessing target tissues.
Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut.
Kotaro
K
Takeda
Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut.
Li-Juan
LJ
Duan
Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut.
Hiromi
H
Takeda
Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut. Electronic address: fong@nso2.uchc.edu.
Guo-Hua
GH
Fong
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004195:Disease Models, Animal; D005263:Femoral Artery / Q000503:physiopathology; D006614:Hindlimb / Q000098:blood supply*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D064799:Hypoxia-Inducible Factor-Proline Dioxygenases / Q000235:genetics / Q000378:metabolism*; D007511:Ischemia / Q000503:physiopathology*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D015398:Signal Transduction; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; C490189:Egln1 protein, mouse; D064799:Hypoxia-Inducible Factor-Proline Dioxygenases