Department of Microbiology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran.
Department of Biology, Faculty of Basic Sciences, Lahijan Branch, Islamic Azad University (IAU), Lahijan, Guilan, Iran.
Arch Microbiol. 2024 Feb 19;206(3):112. doi: 10.1007/s00203-023-03809-0.
Poly(lactic-co-glycolic acid) (PLGA) is a biocompatible polymer that can gradually and consistently release drugs in a controlled manner. In this study, diclofenac sodium-loaded PLGA nanoparticles (DS-PLGA NPs) were produced by solvent evaporation technique and characterized using SEM, DLS, and zeta potential analyses. The antibacterial and antivirulence potential of DS-PLGA NPs against P. aeruginosa strains were examined using broth microdilution, crystal violet staining, hemolysis, and twitching quantification assays. Furthermore, the expression of the quorum sensing (QS) genes, lasI and lasR in P. aeruginosa strains after treatment with 1/2 MIC of DS-PLGA NPs was assessed using real-time PCR. SEM imaging of the synthesized NPs exhibited that the NPs have a spherical structure with a size range of 60-150 nm. The zeta potential of the NPs was - 15.2 mV, while the size of the particles in the aquatic environment was in a range of 111.5-153.8 nm. The MIC of prepared NPs against various strains of P. aeruginosa ranged from 4.5 to 9 mg/mL. Moreover, exposure of bacteria to sub-MIC of DS-PLGA NPs significantly down-regulated the expression of the lasI and lasR genes to 0.51- and 0.75-fold, respectively. Further, prepared NPs efficiently reduced the biofilm formation of P. aeruginosa strains by 9-27%, compared with the controls. Besides, DS-PLGA NPs showed considerable attenuation in bacterial hemolytic activity by 32-88% and twitching motility by 0-32.3%, compared with untreated cells. Overall, the present work exhibited the anti-QS activity of DS-PLGA NPs, which could be a safe and useful approach for treating P. aeruginosa infections.
聚（乳酸-共-乙醇酸）（PLGA）是一种生物相容性聚合物，可在控制下逐渐和持续地释放药物。在这项研究中，通过溶剂蒸发技术制备了载双氯芬酸钠的 PLGA 纳米粒（DS-PLGA NPs），并通过 SEM、DLS 和zeta 电位分析进行了表征。通过肉汤微量稀释、结晶紫染色、溶血和抽动定量测定法，研究了 DS-PLGA NPs 对铜绿假单胞菌菌株的抗菌和抗毒力。此外，通过实时 PCR 评估了铜绿假单胞菌菌株在经过 1/2 MIC 的 DS-PLGA NPs 处理后，群感调节（QS）基因 lasI 和 lasR 的表达。合成的 NPs 的 SEM 成像显示， NPs 具有球形结构，粒径范围为 60-150nm。NPs 的 zeta 电位为-15.2mV，而在水相环境中，颗粒的粒径在 111.5-153.8nm 之间。制备的 NPs 对各种铜绿假单胞菌菌株的 MIC 范围为 4.5-9mg/mL。此外，亚 MIC 的 DS-PLGA NPs 暴露于细菌可将 lasI 和 lasR 基因的表达分别下调至 0.51-0.75 倍。此外，与对照组相比，制备的 NPs 可有效降低铜绿假单胞菌菌株的生物膜形成 9-27%。此外，与未处理的细胞相比，DS-PLGA NPs 可使细菌溶血活性降低 32-88%，抽动运动性降低 0-32.3%。总的来说，本工作显示了 DS-PLGA NPs 的抗 QS 活性，这可能是治疗铜绿假单胞菌感染的一种安全有效的方法。
