Synergistic Antibacterial Effect from Silver Nanoparticles and Anticancer Activity Against Human Lung Cancer Cells

Microbially synthesized silver nanoparticles (AgNPs) with high stability and bioactivity have recently shown considerable promise in biomedical research and application. In this study, AgNPs prepared by Penicillium aculeatum Su1 exhibited effective antibacterial action by inhibiting bacterial growth and destroying cellular structure. Meanwhile, their assessed increased in fold area (IFA) through the Kirby-Bauer disc diffusion method proved that, the AgNPs showed synergistic antibacterial effect on different bacteria when combined with antibiotics, especially for drug-resistant P. aeruginosa (4.58 similar to 6.36-fold) and B. subtilis (4.2-fold). Moreover, the CCK-8 assay and flow cytometric analysis were used to evaluate the cytotoxic effects of AgNPs on normal cells (HBE) and lung cancer cells (HTB-182), which confirmed that they presented higher biocompatibility towards HBE cells when compared with silver ions, but high cytotoxicity in a dose-dependent manner with an IC50 values of 35.00 mu g/mL towards HTB-182 cells by raising intracellular reactive oxygen species (ROS) levels, hindering cell proliferation, and ultimately leading to cell cycle arrest and cell apoptosis. These results demonstrate that, the biosynthesized AgNPs could be a potential candidate for future therapies of infection caused by drug-resistant bacteria, as well as lung squamous cell carcinoma.

Automated summary

In this study, silver nanoparticles synthesized by Penicillium aculeatum Su1 showed effective antibacterial action and synergistic effects when combined with antibiotics. They exhibited higher biocompatibility towards normal cells but higher cytotoxicity towards lung cancer cells.