具有舒张血管和抑制血管重构双重作用的新型抗肺动脉高压药物研究

In this project, based on the extensive clinical practice using inhaled nitric oxide for the treatment of pulmonary arterial hypertension (PAH) and the disclosed phase II results for Bardoxolone Methyl (CDDO-Me) treatment in patients with PAH, a new therapeutical concept, that is combination of pulmonary arterial vasodilatation and vascular remodeling inhibition, is proposed. In this regard, three groups of NO-donating CDDO-Me derivatives (I-III) have been designed and will be synthesized. After inhaled, I-III could mainly distribute in lung tissue, and be decomposed in the presence of lysyl oxidase (LOX), which is over-expressed in lung tissue of PAH patients, to NO and CDDO-Me, generating pulmonary arterial vasodilatation effects as well as antiimflammatory, antioxidative, and vascular remodeling inhibitory activities via inhibition of NF-κB and activation of Nrf2 pathway. Notably, the inhalation administration could avoid the NO release in other tissues or organs, lowering the undesired side effects and thus improving the druggability. The detailed study items include: aerosol formulation study, in vitro NO release study, inhibitory effect against pulmonary artery smooth muscle cells growth and protection effect on pulmonary artery endothelial cells, in vivo tissue distribution investigation, in vivo anti-PAH evaluation, mechanism studies in cell and molecule levels. This project could give a good example for topical administration-based NO-donating drug development, as well as one or two NO-donating candidates with potential intervention of PAH.

基于吸入一氧化氮（NO）气体治疗肺动脉高压（PAH）的临床实践以及齐墩果酸衍生物CDDO-Me有效干预PAH的临床研究结果，本项目提出应用具有舒张血管和抑制血管重构双重作用的药物治疗PAH新策略，设计、合成NO供体型CDDO-Me衍生物I-III，通过雾化吸入给药使其主要分布在肺组织，并在该组织中高表达的赖氨酰氧化酶等作用下释放CDDO-Me和NO。NO产生舒张肺动脉血管活性；CDDO-Me主要抑制NF-κB，激活Nrf2通路，抗炎、抗氧化，发挥抑制肺动脉血管重构的作用。项目研究内容还包括：I-III的雾化剂处方筛选，测定NO释放，评价其对肺动脉平滑肌细胞和肺动脉内皮细胞的影响，研究活性化合物体内组织分布以及体内抗PAH活性，考察其安全性，并从细胞、分子水平上探索其作用机制。本项目的成功实施可为NO供体药物局部给药提供新的思路，同时也为发现新型抗PAH候选新药打下良好的基础。

本项目提出联合舒张血管和抑制血管重构双重作用治疗肺动脉高压（PAH）新策略，利用气体信使分子一氧化氮（NO）舒张血管的活性，联合具有抑制血管重构活性的分子，设计、合成了3类化合物并研究了其抗PAH活性。第一类的NO供体型CDDO-Me衍生物CDDO-NO，通过雾化吸入给药使其主要分布在肺组织，并在肺部酯酶作用下水解释放CDDO-Me和NO。NO产生舒张肺动脉血管活性；CDDO-Me主要抑制NF-κB，激活Nrf2通路，抗炎、抗氧化，发挥抑制肺动脉血管重构的作用，二者协同发挥显著的抗肺动脉高压活性。进一步通过对其混悬吸入制剂的筛选，研究了其有效剂量范围；并研究了体内组织分布、代谢动力学行为。第二类化合物为NO供体型法舒地尔衍生物FNO。这类分子保留了ROCK抑制活性，可抑制血管增生和重构；当雾化吸入进入肺组织中后，可被酯酶水解产生法舒地尔和硝酸酯片段，前者发挥ROCK抑制活性，抑制血管增生和重构并扩张血管，后者可释放出NO扩张血管，降低肺动脉压，发挥协同抗PAH的作用。第三类化合物是法舒地尔二氯乙酸成盐（FDCA）。作为丙酮酸脱氢酶激酶（PDK）的抑制剂，二氯乙酸部分可促进葡萄糖的有氧代谢，减少乳酸生成，减轻炎症损伤，此外也可以通过钾离子通道Kv2.1的上调，制肺动脉平滑肌细胞的增殖、促进其凋亡，产生抗肺动脉高压的活性。法舒地尔部分抑制ROCK，二者协同产生显著的抗PAH活性，部分指标优于上市药物波生坦。通过本项目的实施，发表了SCI论文21篇，申请专利8项，授权中国专利4项。其中CDDO-NO具有较好的转化前景，已和相关制药企业签署框架协议，深入的临床前研究正在有序的进行中。