基于PRRSV致炎作用探讨苦参碱调控IL-1β的机制

研究表明，苦参碱具有抗炎作用并可抑制IL-1β的产生，但其调控IL-1β产生的机制目前仍不清楚。申请人研究发现苦参碱对PRRSV/PCV2感染诱导的小鼠间质性肺炎有显著治疗作用。目前，药物抗炎作用及机制的研究多以LPS作为致炎因子，鲜有以病毒感染诱导炎症反应为研究模型。因此，本项目以PRRSV 5ˊUTR转录物诱导猪肺泡巨噬细胞（PAM）炎症反应为体外模型、以PRRSV感染断奶仔猪造成间质性肺炎为体内模型探讨苦参碱的抗炎机制；采用qPCR和ELISA检测苦参碱在体内外对IL-1β产生的影响；病理组织切片和透射电镜观察苦参碱对仔猪肺脏病理变化的改变；流式细胞术检测苦参碱对支气管肺泡灌洗液（BAL）中各种白细胞含量的影响；Western blot检测苦参碱对proIL-1β和成熟IL-1β产生过程中关键蛋白的作用。基于PRRSV致炎作用，从细胞模型和靶动物模型阐释苦参碱调控IL-1β表达机制。

It is reported that Matrine has anti-inflammatory effect and inhibits IL-1β expression. However the regulation mechanisms remains unclear. Our previous study has demonstrated that Matrine has a significant therapeutic effect on interstitial pneumonia in mice induced by PRRSV/PCV2 co-infection. So far, LPS was normally used as an inflammatory inducer for studying the anti-inflammatory effect and mechanism. The virus infection was rarely used as an inflammatory inducer for this purpose. In this proposal, the 5ˊUTR transcripts of PRRSV will be used as an inducer to induce the inflammatory response in porcine pulmonary alveolar macrophage (PAM) as an in vitro model and interstitial pneumonia in weaning piglets induced by PRRSV infection will be used as an in vivo model to investigate the anti-inflammatory mechanisms of Matrine. qPCR and ELISA will be used to assess the effect of Matrine on IL-1β expression both in vitro and in vivo models. The piglets lung pathological changes will be observed by histopathologic examination and transmission electron microscope. The effect of Matrine on the counts of various white blood cells in bronchoalveolar lavage (BAL) will be determined by flow cytometry. Western blot will be used to detect the effect of Matrine on the key proteins during the expression of proIL-1β and mature IL-1β. In summary, our study will be focus on elucidating the regulation mechanism of Matrine on IL-1β expression both in cell model and target animal model, basing on the inflammatory response induced by PRRSV.