International Journal of Nanomedicine (Aug 2016)
Effects of silver nanoparticles in combination with antibiotics on the resistant bacteria Acinetobacter baumannii
Abstract
Guoqing Wan,1,2 Lingao Ruan,2,3 Yu Yin,2,3 Tian Yang,2,3 Mei Ge,2 Xiaodong Cheng1,4 1School of Life Science and Technology, China Pharmaceutical University, Nanjing, 2Shanghai Laiyi Center for Biopharmaceutical R&D, 3School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 4Department of Integrative Biology & Pharmacology, The University of Texas Health Science Center, Houston, TX, USA Abstract: Acinetobacter baumannii resistance to carbapenem antibiotics is a serious clinical challenge. As a newly developed technology, silver nanoparticles (AgNPs) show some excellent characteristics compared to older treatments, and are a candidate for combating A. baumannii infection. However, its mechanism of action remains unclear. In this study, we combined AgNPs with antibiotics to treat carbapenem-resistant A. baumannii (aba1604). Our results showed that single AgNPs completely inhibited A. baumannii growth at 2.5 µg/mL. AgNP treatment also showed synergistic effects with the antibiotics polymixin B and rifampicin, and an additive effect with tigecyline. In vivo, we found that AgNPs–antibiotic combinations led to better survival ratios in A. baumannii-infected mouse peritonitis models than that by single drug treatment. Finally, we employed different antisense RNA-targeted Escherichia coli strains to elucidate the synergistic mechanism involved in bacterial responses to AgNPs and antibiotics. Keywords: Acinetobacter baumannii, AgNPs, synergistic, antibiotic combination, antisense RNA
