Topical application of zinc oxide nanoparticles reduces bacterial skin infection in mice and exhibits antibacterial activity by inducing oxidative stress response and cell membrane disintegration in macrophages.

Abstract

Here we studied immunological and antibacterial mechanisms of zinc oxide nanoparticles (ZnO-NPs) against human pathogens. ZnO-NPs showed more activity against Staphylococcus aureus and least against Mycobacterium bovis-BCG. However, BCG killing was significantly increased in synergy with antituberculous-drug rifampicin. Antibacterial mechanistic studies showed that ZnO-NPs disrupt bacterial cell membrane integrity, reduce cell surface hydrophobicity and down-regulate the transcription of oxidative stress-resistance genes in bacteria. ZnO-NP treatment also augmented the intracellular bacterial killing by inducing reactive oxygen species production and co-localization with Mycobacterium smegmatis-GFP in macrophages. Moreover, ZnO-NPs disrupted biofilm formation and inhibited hemolysis by hemolysin toxin producing S. aureus. Intradermal administration of ZnO-NPs significantly reduced the skin infection, bacterial load and inflammation in mice, and also improved infected skin architecture. We envision that this study offers novel insights into antimicrobial actions of ZnO-NPs and also demonstrates ZnO-NPs as a novel class of topical anti-infective agent for the treatment of skin infections.

FROM THE CLINICAL EDITOR:

This in-depth study demonstrates properties of ZnO nanoparticles in infection prevention and treatment in several skin infection models, dissecting the potential mechanisms of action of these nanoparticles and paving the way to human applications.

• Authors: Rashmirekha Pati, Ranjit Kumar Mehta, Soumitra Mohanty, Avinash Padhi, Mitali Sengupta, Baskarlingam Vaseeharan, Chandan Goswami, Avinash Sonawane
• Journal: Nanomedicine : nanotechnology, biology, and medicine (Nanomedicine) Vol. 10 Issue 6 Pg. 1195-208 (Aug 2014) ISSN: 1549-9642 [Electronic] United States
• PMID: 24607937 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 Elsevier Inc. All rights reserved.

Chemical References

• Anti-Bacterial Agents
• Zinc Oxide

Topics

• Animals
• Anti-Bacterial Agents (chemistry, pharmacology, therapeutic use)
• Biofilms (drug effects)
• Female
• Humans
• Macrophages (drug effects, microbiology)
• Mice
• Mice, Inbred BALB C
• Monocytes (drug effects, microbiology)
• Mycobacterium (drug effects, physiology)
• Mycobacterium Infections (drug therapy)
• Nanoparticles (chemistry, therapeutic use, ultrastructure)
• Oxidative Stress (drug effects)
• Skin (microbiology)
• Staphylococcal Infections (drug therapy)
• Staphylococcal Skin Infections (drug therapy, microbiology)
• Staphylococcus aureus (drug effects, physiology)
• Zinc Oxide (chemistry, pharmacology, therapeutic use)