CARBON MONOXIDE AND VASCULAR SMOOTH MUSCLE CELL FUNCTION

描述（由申请人提供）：本研究提案的广泛长期目标是将血红素加氧酶-1（HO-1）衍生的一氧化碳（CO）确定为一种新型的生物学重要气体，可调节血管损伤部位的稳态。我们测量了血管平滑肌细胞（SMC）释放的CO，发现SMC衍生的CO以自分泌和旁分泌的方式分别抑制SMC增殖和血小板聚集。该建议的中心假设是HO-1衍生的CO是SMC对血管损伤反应的关键调节剂。为了检验我们的假设，我们计划追求以下三个互补和相互联系的具体目标。在目的1中，我们将利用培养的血管SMC研究CO在调节血管SMC迁移、胶原合成和血管内皮生长因子（VEGF）分泌中的作用。将研究外源性给药和内源性来源的CO的影响。SMC将通过暴露室暴露于CO，而内源性CO的产生将通过腺病毒介导的HO-1基因的转移来诱导。HO-1衍生的CO在调节SMC功能中的作用也将通过从HO-1敲除动物的主动脉收获SMC并将其功能特性与来自野生型动物的SMC进行比较来检查。如果CO被发现改变这些SMC功能，我们将确定cGMP或p38丝裂原活化蛋白激酶信号通路的参与。在目标2中，我们将阐明HO-1在调节胶原沉积和VEGF表达动脉损伤后使用HO-1缺陷的转基因小鼠的行动。此外，我们将研究CO吸入是否可以替代HO-1在防止胶原沉积和VEGF表达在这些动物。在目的3中，我们将探索腺病毒介导的HO-1基因递送对这些动物中胶原积累和VEGF表达的影响。最后，我们将确定CO介导的VEGF释放功能是否以旁分泌方式刺激体外和体内内皮细胞生长。预期这些研究将（a）确立CO作为血管壁对损伤的反应的新调节剂和（B）暗示HO-1/CO系统作为治疗血管纤维增生性疾病的有希望的新治疗靶点。

DESCRIPTION (provided by applicant): The broad long-term objective of this research proposal is to establish heme oxygenase-1 (HO-1)-derived carbon monoxide (CO) as a novel and biologically important gas that regulates homeostasis at sites of vascular injury. We have measured the release of CO from vascular smooth muscle cells (SMC) and found that SMC-derived CO functions in an autocrine and paracrine fashion to inhibit SMC proliferation and platelet aggregation, respectively. The central hypothesis of this proposal is that HO-1-derived CO is a critical regulator of the SMC response to vascular injury. To test our hypothesis we plan to pursue the following three complementary and linked specific aims. In aim 1, we will examine the role of CO in regulating vascular SMC migration, collagen synthesis, and the secretion of vascular endothelial growth factor (VEGF) utilizing cultured vascular SMC. The effect of exogenously administered and endogenously derived CO will be studied. SMC will be exposed to CO via an exposure chamber while endogenous CO production will be induced by adenovirus-mediated transfer of the HO-1gene. The role of HO-1-derived CO in regulating SMC function will also be examined by harvesting SMC from the aorta of HO-1 knockout animals and comparing their functional properties with SMC from wild type animals. If CO is found to alter these SMC functions, we will determine the involvement of the cGMP or p38 mitogen activated protein kinase signaling pathways. In aim 2, we will elucidate the actions of HO-1 in regulating collagen deposition and VEGF expression following arterial injury using transgenic mice deficient in HO-1. In addition, we will investigate if CO inhalation can substitute for HO-1 in preventing collagen deposition and VEGF expression in these animals. In aim 3, we will explore the effect of adenovirus-mediated HO-1 gene delivery on collagen accumulation and VEGF expression in these animals. Finally, we will determine if CO-mediated VEGF release functions in a paracrine manner to stimulate endothelial cell growth both in vitro and in vivo. It is anticipated that these studies will (a) establish CO as a novel regulator of the vessel wall's response to injury and (b) implicate the HO-1/CO system as a promising new therapeutic target in treating vascular fibroproliferative disease.