Phosphodiesterase 3 and Atherosclerosis

动脉粥样硬化病变的进展被认为是一个累及血管的慢性炎症过程。 血管壁的重塑。越来越多的证据表明，直接的病理生物学事件在血管壁中起作用 在动脉粥样硬化中起着重要作用。血管内皮细胞(EC)和平滑肌细胞(VSMC) 炎性细胞因子的重要靶点，也能够产生大量的细胞因子， 趋化因子和黏附分子。动脉粥样硬化的发展可能涉及到血管内皮细胞 抗动脉粥样硬化信号(如一氧化氮、C型利钠药)之间的动态平衡 多肽(CNP和环核苷酸)和促动脉粥样硬化信号(如肿瘤坏死因子α和血管紧张素II)。 环核苷酸磷酸二酯酶(PDE)在调节细胞内环核苷酸(CAMP)中起着关键作用 和cGMP)水平和环核苷酸降解的区隔作用。我们最近已经证明， NO和CNP通过抑制培养的VSMC中NF-kappaB依赖的炎症分子的表达 依赖cGMP的磷酸二酯酶3(PDE3)抑制。PDE3是目前主要的cAMP水解型PDE NO-cGMP和CNP-cGMP抑制VSMC中PKA活性，抑制PKA活性。 核因子-kappaB活化与炎性分子表达。此外，对PDE3功能的抑制 特异性阻断肿瘤坏死因子α刺激的核因子-kappaB活化和炎症分子的表达。这些 结果提示，PDE3活性是VSMC炎症基因表达的重要调节因子 CGMP介导的PDE3活性抑制是NO-cGMP抗炎作用的机制 CNP-cGMP在VSMC中的表达。PDE3在VSMC炎症分子调控中的作用 表达与动脉粥样硬化的形成，我们提出了以下三个目标：目标1：鉴定特定的异构体 PDE3参与调节VSMC中依赖于NF-kappaB的炎症分子的表达。目标 2：体外培养VSMC中PDE3对炎性分子表达的调控作用 使用器官培养系统的血管。目的3：确定VSMC过表达PDE3异构体的效果 利用转基因小鼠研究动脉粥样硬化。

The progression of atherosclerotic lesions is believed to be a chronic inflammatory process involving vascular remodeling of the vessel wall. There is increasing evidence that direct pathobiological events in the vessel wall play an important role in atherosclerosis. Vascular endothelial cell (EC) and smooth muscle cell (VSMC) are both important targets for inflammatory cytokines and also capable of producing significant amounts of cytokines, chemokines, and adhesion molecules. The development of atherosclerosis may involve the perturbation of the homeostatic balance between the anti-atherosclerotic signaling (such as nitric oxide (NO), C-type natriuretic peptide (CNP), and cyclic nucleotides) and the pro-atherosclerotic signaling (such as TNF alpha and Ang II). Cyclic nucleotide phosphodiesterases (PDEs) play critical roles in regulating intracellular cyclic nucleotide (cAMP and cGMP) levels and compartmentalization via degradation of cyclic nucleotides. We have recently shown that NO and CNP inhibited NF-kappaB-dependent inflammatory molecule expression in cultured VSMCs via a cGMP-dependent inhibition of phosphodiesterase 3 (PDE3). PDE3 is the major cAMP-hydrolyzing PDE present in VSMC and its inhibition by NO-cGMP and CNP-cGMP results in increased PKA activity, which inhibits NF-kappaB activation and inflammatory molecule expression. Furthermore inhibition of PDE3 function specifically blocked TNFalpha-stimulated NF-kappaB activation and inflammatory molecule expression. These results suggest that PDE3 activity is a critical regulator of inflammatory gene expression in VSMC and that cGMP-mediated inhibition of PDE3 activity is the mechanism of the anti-inflammatory effects of NO-cGMP and CNP-cGMP in VSMC. To determine the role of PDE3 in the regulation of VSMC inflammatory molecule expression and atherosclerosis formation, we propose the following three aims: Aim 1: Identify the specific isoform of PDE3 involved in regulating NF-kappaB-dependent inflammatory molecule expression in VSMC in vitro. Aim 2: Determine the role of PDE3 in the regulation of inflammatory molecule expression in VSMC in ex vivo cultured vessels using the organ culture system. Aim 3: Determine the effect of VSMC overexpression of a PDE3 isoform on atherosclerosis using genetically modified mice.