PFKFB3 in vascular remodeling

项目摘要 6-磷酸果糖-2-激酶/果糖-2，6-二磷酸酶异构体3（PFKFB 3）是糖酵解的关键酶， 在血管细胞中的调节子。PFKFB 3催化果糖-2，6-二磷酸（F2，6P 2）的合成， 后者是6-磷酸果糖-1-激酶（PFK-1）最有效的激活剂， 糖酵解的酶增殖的血管细胞包括内皮细胞和血管平滑肌细胞 肌细胞是多种血管疾病中血管重塑的主要特征， 肺动脉高压（PAH）。我们和其他人的工作已经证明了一个关键的作用 PFKFB 3在血管生成中的作用。在最近的研究中，我们发现：（1） PDGF/VEGF和低氧可增加肺动脉平滑肌PFKFB 3蛋白水平和活性 肺动脉内皮细胞（PAECs）;（2）抑制PFKFB 3 减弱PDGF/VEGF和缺氧诱导的胶原蛋白合成、过度增殖和对 低氧诱导的肺血管重构与肺动脉平滑肌细胞和肺动脉内皮细胞的凋亡密切相关 在PFKFB 3-/+小鼠中抑制;（4）在平滑肌中PFKFB 3蛋白水平显著增加 细胞和内皮细胞以及丛状病变的特发性肺动脉炎患者的肺动脉 呸。这些数据使我们假设血管细胞中的PFKFB 3在血管形成中具有核心作用。 PFKFB 3的重塑和抑制抑制血管细胞的增殖，并进一步抑制血管内皮细胞的增殖。 肺动脉高压的发展。该提案的目的是使用特定的 PFKFB 3抑制剂和组织特异性PFKFB 3缺失小鼠，以研究PFKFB 3是否以及如何在 血管细胞在PAH的血管重塑中起关键作用。在目标1中，我们将研究 PDGF/VEGF和缺氧通过HIF 1 α介导的PFKFB 3基因表达增加PFKFB 3活性， MAPK介导的PASMC和PAEC中的PFKFB 3磷酸化。在目标2中，我们将研究 由高PFKFB 3活性产生的乳酸盐如何提高Akt活化，导致胶原蛋白合成， PASMCs和PAECs的过度增殖和抗凋亡。在目标3中，我们将研究 在平滑肌细胞中PFKFB 3缺乏的小鼠中，肺血管重塑受到抑制， 在用特异性PFKFB 3抑制剂3-（3-吡啶基）-1-（4-吡啶基）-2-（三氟甲基）吡啶处理的大鼠中， 丙烯-1-酮（3 PO）。这一建议具有高度的翻译性。该项目的完成将推动新的 基于PFKFB 3的抑制血管重塑的范例，并可能导致更有效的 以及与血管重塑相关的疾病的特异性治疗。

PROJECT SUMMARY 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase isoform 3 (PFKFB3) is a critical glycolytic regulator in vascular cells. PFKFB3 catalyzes the synthesis of fructose-2, 6-bisphosphate (F2, 6P2) and the latter is the most potent activator for 6-phosphofructo-1-kinase (PFK-1), one of three rate-limiting enzymes for glycolysis. Proliferation of vascular cells including endothelial cells and vascular smooth muscle cells is the major feature of vascular remodeling in a variety of vascular diseases including pulmonary arterial hypertension (PAH). Ours and the work from others have demonstrated a critical role of endothelial PFKFB3 in angiogenesis. In our recent studies we have found the following: (1) PDGF/VEGF and hypoxia increase the protein level and activity of PFKFB3 in pulmonary artery smooth muscle cells (PASMCs) and pulmonary artery endothelial cells (PAECs); (2) inhibition of PFKFB3 attenuates PDGF/VEGF- and hypoxia-induced collagen synthesis, hyperproliferation and resistance to apoptosis of PASMCs and PAECs; (3) hypoxia-induced pulmonary vascular remodeling was significantly suppressed in PFKFB3-/+ mice; (4) PFKFB3 protein levels are robustly increased in the smooth muscle cells and endothelial cells as well as plexiform lesions of pulmonary arteries of patients with idiopathic PAH. These data led us to hypothesize that PFKFB3 in vascular cells has a central role in vascular remodeling and suppression of PFKFB3 inhibits proliferation of vascular cells and further curbs the development of pulmonary arterial hypertension. The goal of this proposal is designed to use specific PFKFB3 inhibitor and tissue-specific PFKFB3 deletion mice to investigate whether and how PFKFB3 in vascular cells plays a crucial role in vascular remodeling of PAH. In Aim 1, we will investigate whether PDGF/VEGF and hypoxia increase PFKFB3 activity via HIF1α-mediated PFKFB3 gene expression and MAPK-mediated PFKFB3 phosphorylation in PASMCs and PAECs. In Aim 2, we will study whether and how lactate, arising from high PFKFB3 activity, elevates Akt activation, leading to collagen synthesis, hyperproliferation and resistance to apoptosis of PASMCs and PAECs. In Aim 3, we will examine whether pulmonary vascular remodeling is suppressed in mice with PFKFB3 deficiency in smooth muscle cells or endothelial cells, and in rat treated with a specific PFKFB3 inhibitor 3-(3-pyridinyl)-1-(4-pyridinyl)-2- propen-1-one (3PO). This proposal is highly translational. Completion of this project will advance a new PFKFB3-based paradigm for the suppression of vascular remodeling and may lead to a more effective and specific therapy of diseases associated with vascular remodeling.