Discovery of new quaternized norharmane dimers as potential anti-MRSA agents
Discovery of new quaternized norharmane dimers as potential anti-MRSA agents
复制标题
DOI：
10.1016/j.jare.2023.11.005
复制
发表时间：
2024-08-18
影响因子：
10.7
通讯作者：
Wan，Jian-Bo
中科院分区：
文献类型：
--
作者：
Dai，Jiang-Kun;Dan，Wen-Jia;Wan，Jian-Bo
耐甲氧西林金黄色葡萄球菌（MRSA）引起的感染严重威胁着公众健康。天然产物为基础的抗MRSA药物的发现，用于治疗感染性疾病已成为当前的研究focus.ObjectivesThis研究的目的是确定有前途的抗MRSA药物的基础上，通过季铵化或二聚修饰天然norharmane.MethodsA共32 norharmane类似物的制备和表征具有明确的机制。采用肉汤二倍稀释法测定其抗菌活性和耐药性发展趋势。采用细胞计数试剂盒-8和溶血试验评价其生物安全性。通过菌落计数和结晶紫染色试验检测血浆稳定性、杀菌模式和生物膜破坏效果。荧光显微镜、代谢组学分析、对接模拟和光谱滴定等方法揭示了其抗MRSA的作用机制。结果化合物5a在体外和体内均表现出较强的抗MRSA活性，且在有效剂量范围内具有较低的细胞毒性和溶血性。此外，化合物5在50%血浆中显示出良好的稳定性、低的耐药性发展趋势和破坏细菌生物膜的能力。结论化合物5具有抑制细菌细胞壁生物合成、破坏细胞膜、干扰能量代谢和氨基酸代谢途径、干扰蛋白质合成和核酸功能等作用，为进一步开发新一代治疗性抗生素提供了有价值的信息。
IntroductionMethicillin-resistantStaphylococcus aureus(MRSA)-caused infections greatly threaten public health. The discovery of natural-product-based anti-MRSA agents for treating infectious diseases has become one of the current research focuses.ObjectivesThis study aims to identify promising anti-MRSA agents with a clear mechanism based on natural norharmane modified by quaternization or dimerization.MethodsA total of 32 norharmane analogues were prepared and characterized. Their antibacterial activities and resistance development propensity were tested by the broth double-dilution method. Cell counting kit-8 and hemolysis experiments were used to assess their biosafety. The plasma stability, bactericidal mode, and biofilm disruption effects were examined by colony counting and crystal violet staining assays. Fluorescence microscopy, metabolomic analysis, docking simulation and spectra titration revealed its anti-MRSA mechanisms. The mouse skin infection model was used to investigate thein vivoefficacy.ResultsCompound5awas selected as a potential anti-MRSA agent, which exhibited potent anti-MRSA activityin vitroandin vivo, low cytotoxicity and hemolysis under an effective dose. Moreover, compound5ashowed good stability in 50% plasma, a low tendency of resistance development and capabilities to disrupt bacterial biofilms. The mechanism studies revealed that compound5acould inhibit the biosynthesis of bacteria cell walls, damage the membrane, disturb energy metabolism and amino acid metabolism pathways, and interfere with protein synthesis and nucleic acid function.ConclusionsThese results suggested that compound5ais a promising candidate for combating MRSA infections, providing valuable information for further exploiting a new generation of therapeutic antibiotics.