Angiotensin II failitated angiogenesis mediated through macrophage migration inhibitory factor activation in hindlimb ischemic

背景-巨噬细胞移动抑制因子(MIF)是由氧化应激分泌的，在调节巨噬细胞和T细胞的活化等炎症状态中起重要作用，也是刺激细胞生长和诱导其他细胞因子和酶如血管内皮生长因子(VEGF)和基质金属蛋白酶(MMPs)的因子。血管内皮生长因子和基质金属蛋白酶被认为在多种细胞类型中影响新生血管形成。综上所述，我们评估了MIF可能是刺激缺血反应中血管生成的重要因素的假说。方法和结果--为了验证这一假说，我们研究了MIF过度表达(TG)小鼠对组织缺血的反应中的血管生成。我们将手术诱导的单侧后肢缺血模型应用于MIF、TG和野生型(WT)小鼠(C57BL/6)。用激光多普勒血流显像(缺血/正常灌注率)、血管造影术(血管造影评分)和组织学毛细血管密度(vWF抗体)分析缺血后肢血管生成和侧支血管形成情况。逆转录-聚合酶链式反应检测血管内皮生长因子和基质金属蛋白酶-2和-9的信息和蛋白表达。与WT小鼠相比，MIF TG小鼠后肢缺血后的血管生成和侧支血管形成明显增加。在非缺血区，MIF-TG小鼠与WT小鼠在非缺血区的VEGF蛋白水平无差异。在缺血区，与WT小鼠相比，TG小鼠的VEGFmRNA和蛋白表达水平升高。与WT小鼠相比，Tg组小鼠非缺血区的MMP9mRNA表达增加。这种增加的表达在TG小鼠的缺血区得到了加强，尽管它们之间的基质金属蛋白酶-2没有差异。抗MIF的中和抗体显著抑制缺血后血管生成、血管内皮生长因子和基质金属蛋白酶-9的表达

Background-Macrophage migration inhibitory factor (MIF), which we have reported to be secreted by oxidative stress, plays a crucial role in several inflammatory conditions such as regulating the activation of macrophages and T cells, and it also acts as a factor stimulating cell growth and inducing other cytokines and enzymes such as vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). VEGF and MMPs are thought to influence neovascularization in many cell type. Taken together, we assessed the hypothesis that MIF could be an important factor stimulating angiogenesis in response to ischemia. Methods and Results-To test the hypothesis, we examined angiogenesis in response to tissue ischemia in MIF overexpressed (TG) mice. We applied surgically-induced unilateral hindlimb ischemia model to MIF TG and wild type (WT) mice (C57BL/6). Angiogenesis and collateral vessel formation in the ischemic hindlimb were analyzed by using laser Doppler perfusion Imager (ischemic/normal perfusion ratio), angiography (angiogrphic score) and histological capillary density with vWF antibody. Message and protein expression of the VEGF and MMPs (-2 and -9) were determined with RT-PCR. Angiogenesis and collateral vessel formation in response to hindlimb ischemia were markedly increased in MIF TG mice compared with WT mice. VEGF protein levels were not different between the MIF TG mice and WT mice at non-ischemic area. In the ischemic area VEGF mRNA and protein expression levels were increased in the TG mice compared with the WT mice. MMP-9 mRNA expression was increased at non-ischemic region in the TG mice compared with the WT mice. This increased expression was reinforced in the ischmic region in the TG mice, although no difference in MMP-2 between them. A neutralizing antibody against MIF significantly suppressed angiogenesis, VEGF expression, and MMP-9 expression in response to ischemia