Lee Eunjung, Shin Areum, Kim Yangmee
Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul, South Korea.
Arch Insect Biochem Physiol. 2015 Jan;88(1):31-44. doi: 10.1002/arch.21193. Epub 2014 Oct 15.
Cecropin A is a novel 37-residue cecropin-like antimicrobial peptide isolated from the cecropia moth, Hyalophora cecropia. We have demonstrated that cecropin A is an antibacterial agent and have investigated its mode of action. In this study, we show that cecropin A has potent antimicrobial activity against 2 multidrug resistant organisms-Acinetobacter baumanii and-Pseudomonas aeruginosa. Interactions between cecropin A and membrane phospholipids were studied using tryptophan blue shift experiments. Cecropin A has a strong interaction with bacterial cell mimetic membranes. These results imply that cecropin A has selectivity for bacterial cells. To address the potential the rapeutic efficacy of cecropin A, its anti-inflammatory activities and mode of action in mouse macrophage-derived RAW264.7 cells stimulated with lipopolysaccharide (LPS) were examined. Cecropin A suppressed nitrite production, mTNF-α, mIL-1β, mMIP-1, and mMIP-2 cytokine release in LPS-stimulated RAW264.7 cells. Furthermore, cecropin A inhibited intracellular cell signaling via the ERK, JNK, and p38 MAPK pathway, leading to the prevention of COX-2 expression in LPS-stimulated RAW264.7 cells. These results strongly suggest that cecropin A should be investigated as a potential agent for the prevention and treatment of inflammatory diseases.
天蚕素A是一种从樗蚕蛾（Hyalophora cecropia）中分离出的新型37个氨基酸残基的类天蚕素抗菌肽。我们已经证明天蚕素A是一种抗菌剂，并对其作用方式进行了研究。在本研究中，我们表明天蚕素A对两种多重耐药菌——鲍曼不动杆菌和铜绿假单胞菌具有强大的抗菌活性。使用色氨酸蓝移实验研究了天蚕素A与膜磷脂之间的相互作用。天蚕素A与细菌细胞膜模拟物有强烈的相互作用。这些结果表明天蚕素A对细菌细胞具有选择性。为了探讨天蚕素A的潜在治疗效果，研究了其在脂多糖（LPS）刺激的小鼠巨噬细胞RAW264.7中的抗炎活性和作用方式。天蚕素A抑制了LPS刺激的RAW264.7细胞中亚硝酸盐的产生、mTNF-α、mIL-1β、mMIP-1和mMIP-2细胞因子的释放。此外，天蚕素A通过ERK、JNK和p38 MAPK途径抑制细胞内信号传导，从而防止LPS刺激的RAW264.7细胞中COX-2的表达。这些结果强烈表明，天蚕素A应作为预防和治疗炎症性疾病的潜在药物进行研究。
