Wang Jingkai, Zeng Fanli, Chen Xiaoling, Wang Tao, Wang Lei, Zhou Mei, Jiang Yangyang, Chen Tianbao, Fang Yongfei, Zhang Jinwei
Department of Traditional Chinese Medicine, Chongqing General Hospital, Chongqing, China.
Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom.
Front Chem. 2025 May 19;13:1579097. doi: 10.3389/fchem.2025.1579097. eCollection 2025.
Antimicrobial peptides (AMPs) are promising candidates for combating multidrug-resistant infections, but their clinical application is often limited by challenges such as poor selectivity and high cytotoxicity. This study aimed to optimize the therapeutic potential of brevinin-1pl, a frog-derived AMP with broad-spectrum antimicrobial and anticancer activities.
Major experimental approaches encompassed antibacterial activity evaluation, hemolytic potential assessment, bactericidal rate determination via time-kill kinetics, SYTOX Green-based membrane integrity analysis, and MTT assays for anti-proliferative effects.
Substitutions with arginine (brevinin-1pl-2R and brevinin-1pl-5R) enhanced activity against Gram-positive bacteria but reduced efficacy against Gram-negative strains. Lysine substitution (brevinin-1pl-6K) decreased activity against Gram-positive bacteria due to reduced hydrophobicity. In contrast, histidine substitution (brevinin-1pl-3H) showed diminished activity against Gram-negative bacteria (e.g., MRSA MIC increased from 2 µM to 4 µM) but reduced hemolysis, indicating improved selectivity. Mechanistic studies using SYTOX green assays confirmed membrane disruption as a primary mode of action, while suggesting alternative mechanisms for Gram-positive and Gram-negative . The brevinin-1pl and its analogues demonstrated significant inhibitory efficacy against both MCF-7 breast cancer cells and H838 non-small cell lung cancer cells at a concentration of 10 M. Notably, brevinin-1pl-3H exhibited low cytotoxicity toward normal HaCaT cells despite its high hydrophobicity, suggesting potential for dermatological applications.
These findings demonstrate that strategic amino acid substitutions can optimize the therapeutic potential of AMPs, offering a promising approach to develop peptides with enhanced efficacy and reduced clinical side effects.
抗菌肽是对抗多重耐药感染的有潜力的候选物，但其临床应用常常受到选择性差和细胞毒性高等挑战的限制。本研究旨在优化brevinin-1pl的治疗潜力，brevinin-1pl是一种源自青蛙的具有广谱抗菌和抗癌活性的抗菌肽。
主要实验方法包括抗菌活性评估、溶血潜力评估、通过时间杀灭动力学测定杀菌率、基于SYTOX Green的膜完整性分析以及用于抗增殖作用的MTT测定。
用精氨酸替代（brevinin-1pl-2R和brevinin-1pl-5R）增强了对革兰氏阳性菌的活性，但降低了对革兰氏阴性菌的效力。赖氨酸替代（brevinin-1pl-6K）由于疏水性降低而降低了对革兰氏阳性菌的活性。相比之下，组氨酸替代（brevinin-1pl-3H）对革兰氏阴性菌的活性降低（例如，耐甲氧西林金黄色葡萄球菌的最低抑菌浓度从2 μM增加到4 μM），但溶血作用降低，表明选择性提高。使用SYTOX green测定的机制研究证实膜破坏是主要作用方式，同时提示革兰氏阳性菌和革兰氏阴性菌存在其他机制。brevinin-1pl及其类似物在10 μM浓度下对MCF-7乳腺癌细胞和H838非小细胞肺癌细胞均表现出显著的抑制效力。值得注意的是，brevinin-1pl-3H尽管具有高疏水性，但对正常HaCaT细胞表现出低细胞毒性，表明其在皮肤病学应用方面具有潜力。
这些发现表明，战略性氨基酸替代可优化抗菌肽的治疗潜力，为开发疗效增强和临床副作用减少的肽提供了一种有前景的方法。
