Nanoparticle production and use is growing exponentially. Silver nanoparticles (AgNPs) are produced in increasing quantities largely for antimicrobial purposes, in applications that guarantee significant human exposure. Therefore, it is critical to elucidate any potential human health hazards. Indeed, research to date has demonstrated that AgNPs are among the most toxic nanoparticles tested, perhaps not surprising given their intended biocidal application. However, the mechanism of toxicity of AgNPs is not fully resolved, and little effort has been spent addressing the possibility that certain genetic backgrounds may predispose some individuals to increased risk. In this project, we will test the hypothesis is that an important mode of action of AgNPs is mitochondrial toxicity. The rationale for this hypothesis is that many antimicrobial agents also exert mitochondrial toxicity, because mitochondria are derived from bacteria. Furthermore, the possibility that this is also true of AgNPs is supported by a number of relatively nonspecific assays of mitochondrial function reported in the literature, and by our own preliminary data. Testing this hypothesis is critical for human health because if AgNPs cause significant mitochondrial toxicity, it is likely that deficiencies in human disease genes critical for mitochondrial homeostasis will result in increased vulnerability to AgNP toxicity. Finally, we will test this hypothesis using a range of AgNPs that vary in size, coating, and surface charge.

Public Health Relevance

Silver nanoparticles are produced in increasing quantities in applications that guarantee significant human exposure, and are among the most toxic nanoparticles tested. However, the mechanism of toxicity of silver nanoparticles is not fully resolved, and little effort has been spent addressing the possibility that certain genetic backgrounds may predispose some individuals to increased risk. This research will test whether silver nanoparticles cause toxicity by targeting mitochondria, and whether individuals with genetic differences associated with mitochondrial function might be at more risk of mitochondrial toxicity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21ES026743-02
Application #
9432516
Study Section
Systemic Injury by Environmental Exposure (SIEE)
Program Officer
Shaughnessy, Daniel
Project Start
2017-03-01
Project End
2019-02-28
Budget Start
2018-03-01
Budget End
2019-02-28
Support Year
2
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Duke University
Department
Type
Earth Sciences/Resources
DUNS #
044387793
City
Durham
State
NC
Country
United States
Zip Code
27705
Meyer, Joel N; Leuthner, Tess C; Luz, Anthony L (2017) Mitochondrial fusion, fission, and mitochondrial toxicity. Toxicology 391:42-53
Gonzalez-Moragas, Laura; Maurer, Laura L; Harms, Victoria M et al. (2017) Materials and toxicological approaches to study metal and metal-oxide nanoparticles in the model organism Caenorhabditis elegans. Mater Horiz 4:719-746