New toxicity mechanism of silver nanoparticles: promoting apoptosis and inhibiting proliferation

Huijing Bao; Xiaoxu Yu; Chen Xu; Xue Li; Zhaoyang Li; Dianjun Wei; Yunde Liu

doi:10.1371/journal.pone.0122535

New toxicity mechanism of silver nanoparticles: promoting apoptosis and inhibiting proliferation

PLoS One. 2015 Mar 30;10(3):e0122535. doi: 10.1371/journal.pone.0122535. eCollection 2015.

Authors

Huijing Bao¹, Xiaoxu Yu¹, Chen Xu², Xue Li¹, Zhaoyang Li³, Dianjun Wei⁴, Yunde Liu¹

Affiliations

¹ School of Laboratory Science, Tianjin Medical University, Tianjin, China.
² The 4th Central Hospital, Tianjin, China, China.
³ School of Materials Science and Engineering, Tianjin University, Tianjin, China.
⁴ The Department of Laboratory Science, The Second Hospital of Tianjin Medical University, Tianjin, China.

Abstract

Silver nanoparticles are increasingly recognized for their utility in biological applications, especially antibacterial effects. Herein, we confirmed the antibacterial effect of silver nanoparticles on Escherichia coli using the conventional optical density (OD) and colony-forming units (CFU) method and used flow cytometry (FC), TEM and BrdU ELISA to investigate the mechanisms of this effect. From the results, we conclude that AgNPs can simultaneously induce apoptosis and inhibit new DNA synthesis in the cells in a positive concentration-dependent manner. This study presents the first induction of apoptosis in these bacteria by AgNPs in this field. Our findings may provide a new strategy for the use of silver nanoparticles in antibacterial applications.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / chemistry*
Anti-Bacterial Agents / pharmacology*
Apoptosis / drug effects*
Cell Proliferation / drug effects
DNA, Bacterial / biosynthesis
Dose-Response Relationship, Drug
Escherichia coli / cytology
Escherichia coli / drug effects
Escherichia coli / growth & development
Escherichia coli / metabolism
Metal Nanoparticles*
Silver / chemistry*
Silver / pharmacology*

Substances

Anti-Bacterial Agents
DNA, Bacterial
Silver

Grants and funding

This work was supported by the key discipline of Tianjin medical funding (201301), Tianjin medical university funding (2011KY42). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.