Vascular Program, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Proc Natl Acad Sci U S A. 2009 Dec 1;106(48):20399-404. doi: 10.1073/pnas.0911921106. Epub 2009 Nov 30.
Ischemia induces the production of angiogenic cytokines and the homing of bone-marrow-derived angiogenic cells (BMDACs), but these adaptive responses become impaired with aging because of reduced expression of hypoxia-inducible factor (HIF)-1alpha. In this study, we analyzed the effect of augmenting HIF-1alpha levels in ischemic limb by intramuscular injection of AdCA5, an adenovirus encoding a constitutively active form of HIF-1alpha, and intravenous administration of BMDACs that were cultured in the presence of the prolyl-4-hydroxylase inhibitor dimethyloxalylglycine (DMOG) to induce HIF-1 expression. The combined therapy increased perfusion, motor function, and limb salvage in old mice subjected to femoral artery ligation. Homing of BMDACs to the ischemic limb was dramatically enhanced by intramuscular AdCA5 administration. DMOG treatment of BMDACs increased cell surface expression of beta(2) integrins, which mediated increased adherence of BMDACs to endothelial cells. The effect of DMOG was abolished by coadministration of the HIF-1 inhibitor digoxin or by preincubation with a beta(2) integrin-blocking antibody. Transduction of BMDACs with lentivirus LvCA5 induced effects similar to DMOG treatment. Thus, HIF-1alpha gene therapy increases homing of BMDACs to ischemic muscle, whereas HIF-1 induction in BMDACs enhances their adhesion to vascular endothelium, leading to synergistic effects of combined therapy on tissue perfusion.
缺血诱导生成血管生成细胞因子和骨髓源性血管生成细胞（BMDAC）的归巢，但这些适应性反应由于缺氧诱导因子（HIF）-1α表达减少而在衰老时受损。在这项研究中，我们通过肌肉内注射 AdCA5（一种编码 HIF-1α的组成型激活形式的腺病毒）和静脉内给予在脯氨酰-4-羟化酶抑制剂二亚甲基氧杂环丁烷（DMOG）存在下培养的 BMDAC 来分析通过增加缺血肢体中的 HIF-1α 水平来增强其作用。联合治疗可增加年老小鼠股动脉结扎后灌注、运动功能和肢体存活。肌肉内 AdCA5 给药可显著增加 BMDAC 向缺血肢体的归巢。DMOG 处理 BMDAC 可增加β2 整联蛋白的细胞表面表达，从而增加 BMDAC 与内皮细胞的粘附。与 HIF-1 抑制剂地高辛共给药或用β2 整联蛋白阻断抗体预孵育可消除 DMOG 的作用。用慢病毒 LvCA5 转导 BMDAC 可诱导类似于 DMOG 处理的作用。因此，HIF-1α基因治疗增加 BMDAC 向缺血肌肉的归巢，而 BMDAC 中 HIF-1 的诱导增强其与血管内皮的粘附，从而导致联合治疗对组织灌注的协同作用。
