abstract
The expansion of biomedical and therapeutic applications of silver nanoparticles (AgNPs) raises the need to further understand their biological effects on human cells. In this work, NMR metabolomics has been applied to reveal the metabolic effects of AgNPs toward human hepatoma (HepG2) cells, which are relevant with respect to nanoparticle accumulation and detoxification. Cellular responses to widely disseminated citrate-coated AgNPs (Cit30) and to emergent biogenic AgNPs prepared using an aqueous plant extract as reducing and stabilizing agent (GS30) have been compared with a view to assess the influence of nanoparticle I coating on the metabolic effects produced. Subtoxic concentrations (IC5 and IC20) of both nanoparticle types caused profound changes in the cellular metabolome, suggesting adaptations in energy production processes (glucose metabolism and the phosphocreatine system), antioxidant defenses, protein degradation and lipid metabolism. These signatures were proposed to reflect mainly metabolism-mediated protective mechanisms and were found to be largely common to Cit30 and GS30 AgNPs, although differences in the magnitude of response, not captured by conventional cytotoxicity assessment, were detected. Overall, this study highlights the value of NMR metabolomics for revealing subtoxic biological effects and helping to understand cell-nanomaterial interactions.
keywords
CYTOTOXICITY; AUTOPHAGY; NANOTOXICOLOGY; INHIBITION; TOXICITY; HEPATOMA; DEATH
subject category
Biochemistry & Molecular Biology
authors
Carrola, J; Pinto, RJB; Nasirpour, M; Freire, CSR; Gil, AM; Santos, C; Oliveira, H; Duarte, IF
our authors
Ana Maria Pissarra Coelho Gil
Associate Professor with Aggregation
Carmen Sofia da Rocha Freire Barros
Coordinating Researcher
Helena Oliveira
Post-Doc Fellowship
Iola Melissa Fernandes Duarte
Principal Researcher
Joana Carolina Quintela Carrola
PhD Student
Maryam Nasirpour
MSc Student
Ricardo Pinto
ResearcherGroups
G4 - Renewable Materials and Circular Economy
G5 - Biomimetic, Biological and Living Materials
acknowledgements
This work was developed in the scope of the projects CICECO-Aveiro Institute of Materials (ref. FCT UID/CTM/50011/2013) and CESAM (ref. FCT UID/AMB/50017/2013), financed by national funds through the FCT/MEC and when applicable cofinanced by the European Regional Development Fund (FEDER) under the PT2020 Partnership Agreement. Funding to the project FCOMP-01-0124-FEDER-021456 (ref. FCT PTDC/SAU-TOX/120953/2010) by FEDER through COMPETE and by national funds through FCT, financial support from the European Union Framework Programme for Research and Innovation HORIZON 2020, under the TEAMING grant agreement no. 739572 - The Discoveries CTR, and the FCT-awarded grants (SFRH/BD/79494/2011, SFRH/BPD/111736/2015 and SFRH/BPD/89982/2012) are acknowledged. I.F.D and C.S.R.F. acknowledge the FCT/MCTES for research contracts under the Program "Investigador FCT". Tiago Pedrosa is thanked for laboratory assistance, Dr. Antonio Barros for helpful advice regarding statistical analysis, and Prof. Ruth Duncan for insightful discussions. Dr. Manfred Spraul, Bruker BioSpin (Germany) is thanked for access to software and spectral database. The Portuguese National NMR (PTNMR) Network, supported with FCT funds, is also acknowledged.