基于Pyk2/p38MAPK/HDAC2通路探讨全真一气汤抑制COPD大鼠肺损伤机制

At present,the study in pathogenesy of COPD suggests that alveolar macrophages and neutrophils induced airway stenosis with fibrosis,pulmonary parenchymal damage and mucus hypersecretion,all of which play an important role in the progression of irreversible airflow limitation.The activation of proline protein tyrosine kinase Pyk2 and downstream factor p38MAPK,CK2a,HDAC2,IL-8 activation in chronic lung inflammation play an important role in the development.We hypothesized that Pyk2/p38MAPK/HDAC2/DES may become a new pathway in the pathogenesis of COPD,however,the process of lung injury of COPD mediated by Pyk2 has not yet been reported.The project in previous research has found that QuanZhenYiQiTan promoted HDAC2 expression in lung tissue of COPD rats.To further observe the effects of drugs on lung injury in COPD signal transduction pathway,we will plan to build Pyk2-siRNA slow virus vector and discusses Pyk2 gene silencing effect on COPD rats with lung injury,analysising signal pathway mediated by Pyk2 and its effect on COPD,elucidating the mechanism of the prevention and treatment of COPD lung injury.Providing a basis for molecular biology on treating COPD with Chinese medicine.

目前对COPD发病机制的研究表明，肺泡巨噬细胞、中性粒细胞诱导的气道狭窄与纤维化、肺实质破坏及粘液分泌亢进在不可逆的气流受限进行性加重中占有重要的地位。脯氨酸蛋白酪氨酸激酶Pyk2的激活及下游因子p38MAPK、CK2a、HDAC2、IL-8的激活在慢性肺部炎症发生发展中起重要作用。我们推测Pyk2/p38MAPK/HDAC2/DES可能成为COPD发病的一个新信号通路。然而目前Pyk2如何介导COPD肺损伤过程尚未见报道。本项目在前期研究中已发现，全真一气汤可促进COPD大鼠肺组织内HDAC2表达，为进一步探讨药物对COPD肺损伤的作用机制，观察药物对COPD肺损伤信号转导通路的影响。拟构建Pyk2—siRNA慢病毒载体，探讨Pyk2基因沉默对COPD大鼠肺损伤的影响，解析Pyk2介导的信号途径及其对COPD的影响，阐明该方防治COPD肺损伤的机理，为中药治疗COPD提供分子生物学依据。

肺泡巨噬细胞诱导的气道狭窄与纤维化、肺实质破坏及粘液分泌亢进在COPD不可逆的气流受限进行性加重中占有重要的地位。脯氨酸蛋白酪氨酸激酶Pyk2的激活及下游因子p38MAPK、CK2a、HDAC2、IL-8的表达在慢性肺部炎症发生发展中起重要作用。本项目在前期研究中已发现，全真一气汤可促进COPD大鼠肺组织内HDAC2表达。因此我们提出全真一气汤通过Pyk2/p38MAPK/HDAC2/DES信号通路抑制COPD肺损伤的科学假说。本研究通过构建Pyk2—siRNA慢病毒载体及过表达质粒等技术，探讨全真一气汤、Pyk2基因沉默或过表达调控下游p38MAPK/HDAC2/DES信号通路对COPD大鼠肺损伤的影响。研究表明：（1）COPD大鼠p-Pyk2、p-p38MAPK和CK2的表达被激活，而HDAC2的表达被下调，血清中IL-8、DES被显著抑制；（2）Pyk2—siRNA慢病毒载体及过表达质粒转染后，下游p38MAPK/HDAC2/DES信号通路显著受影响；（3）全真一气汤能够明显抑制Pyk2的激活，并通过下游p38MAPK/HDAC2/DES信号通路改善COPD肺功能损伤。本研究解析Pyk2介导的信号途径及其对COPD的影响，阐明该方防治COPD肺损伤的机理，为中药治疗COPD提供分子生物学依据。