Department of Microbiology and Immunology, School of Medicine, College of Medicine, China Medical University, Taiwan.
Division of Nephrology, USA.
Eur J Pharmacol. 2024 Oct 5;980:176867. doi: 10.1016/j.ejphar.2024.176867. Epub 2024 Aug 5.
MARCKS (myristoylated alanine-rich C kinase substrates) serves as a substrate for protein kinase C, residing in the plasma membrane while acts as an actin filament crosslinking protein. This investigation aims to elucidate phosphorylated MARCKS (p-MARCKS) levels and activity in allergic asthma patients and explore the therapeutic potential of peptide inhibitors targeting p-MARCKS in an acute mouse model of allergic asthma.
Immunohistochemistry and histology staining were employed on lung tissue slides to evaluate p-MARCKS expression and allergic asthma symptoms. Airway resistance was measured using invasive whole-body plethysmography. Flow cytometry detected lung dendritic cell migration, and migration/maturation assays were conducted on isolated murine bone marrow-derived dendritic cells (BM-DCs).
Elevated p-MARCKS expression was observed in both human asthmatic tissues and animal models immunized with ovalbumin or Alternaria alternata. Remarkably, asthmatic individuals showed elevated high p-MARCKS expression in lung tissues. Intraperitoneal injection of the peptide MPS, targeting the MARCKS phosphorylation site domain, before allergen challenged, effectively suppressed MARCKS phosphorylation in murine lung tissues. MPS inhibited both in vivo and in vitro migration and maturation of dendritic cells (BM-DCs) and reduced Th2-related lymphocyte activation in bronchoalveolar lavage fluid (BALF). MPS pretreatment additionally suppressed all symptoms associated with allergic airway asthma, including a reduction in inflammatory cell influx, airway mucous cell metaplasia, and airway hyperreactivity.
These findings suggest that phosphorylated MARCKS occurs in asthmatic lung tissue, and the inhibition of MARCKS phosphorylation by the MPS peptide reduces dendritic cell migration and Th2-related lymphocytes in the lungs in a murine model of acute asthma.
MARCKS（豆蔻酰化丙氨酸丰富的 C 激酶底物）作为蛋白激酶 C 的底物，位于质膜上，同时作为肌动蛋白丝交联蛋白发挥作用。本研究旨在阐明过敏性哮喘患者中磷酸化 MARCKS（p-MARCKS）的水平和活性，并探讨靶向 p-MARCKS 的肽抑制剂在过敏性哮喘急性小鼠模型中的治疗潜力。
采用免疫组织化学和组织学染色方法评估肺组织切片中的 p-MARCKS 表达和过敏性哮喘症状。通过侵入性全身 plethysmography 测量气道阻力。流式细胞术检测肺树突状细胞迁移，对分离的小鼠骨髓来源树突状细胞（BM-DC）进行迁移/成熟测定。
在人类哮喘组织和卵清蛋白或 Alternaria alternata 免疫的动物模型中均观察到 p-MARCKS 表达升高。值得注意的是，哮喘患者的肺组织中显示出高 p-MARCKS 表达升高。在过敏原攻击前腹腔内注射靶向 MARCKS 磷酸化位点结构域的肽 MPS，可有效抑制小鼠肺组织中 MARCKS 的磷酸化。MPS 抑制体内和体外树突状细胞（BM-DC）的迁移和成熟，并减少支气管肺泡灌洗液（BALF）中的 Th2 相关淋巴细胞激活。MPS 预处理还抑制了与过敏性气道哮喘相关的所有症状，包括炎症细胞浸润减少、气道粘液细胞化生和气道高反应性。
这些发现表明磷酸化 MARCKS 发生在哮喘肺组织中，MPS 肽抑制 MARCKS 磷酸化可减少急性哮喘小鼠模型中肺部的树突状细胞迁移和 Th2 相关淋巴细胞。
