Carbonic anhydrase inhibition, antioxidant activity against alveolar epithelial cells and antibacterial effect against Klebsiella pneumoniae enabled by synthesized silica nanoparticles through laser ablation technique

• DOI: 10.1016/j.lfs.2021.119032
• Publication Date: 2021-01-13T16:48:13Z
• Authors: Na Xu; Wujie Lu; Lijie Meng; Xu Feng; Jingjing Xuan; Fangfang Liu; Zhijun Feng
• Keywords: Klebsiella pneumonia; IC50; Acetazolamide; Formazan

Silica (SiO2) nanoparticles (NPs) were synthesized by laser ablation method and were characterized by TEM and DLS techniques. Afterwards, their inhibition activity against carbonic anhydrase (CA) isoforms (CA I and CA II) was explored by experimental and theoretical analysis. Also, the protective effect of SiO2 NPs against H2O2-induced oxidative stress in alveolar epithelial cells (A549) were assessed by measurement of MTT, ROS level, CAT and SOD activity and GSH content. Finally, the NPs were screened for their antimicrobial activity using the MICs method against the Klebsiella pneumoniae. The result showed that the synthesized NPs have a size of around 40 nm. The inhibition activity by comparing IC50 values with acetazolamide as a positive control revealed that SiO2 NPs in comparison with acetazolamide served as potent inhibitors against CA isoforms which was also confirmed by docking studies. The cellular assays indicated that the SiO2 NPs with a concentration of 20 μg/mL stimulated a significant antioxidant activity against H2O2-induced oxidative cell damage through activation of CAT and SOD, an increase in the GSH content and reducing the level of ROS. The synthesize NPs also showed a good inhibition effect against Klebsiella pneumoniae as compared to Sulfamethoxazole as a positive control. In conclusion, this data may provide some useful information on the development of some platforms for pneumonia treatment and management.