Concentration-dependent, size-independent toxicity of citrate capped AuNPs in Drosophila melanogaster

• Published in: PloS one Vol. 7; no. 1; p. e29980
• Main Authors: Vecchio, Giuseppe, Galeone, Antonio, Brunetti, Virgilio, Maiorano, Gabriele, Sabella, Stefania, Cingolani, Roberto, Pompa, Pier Paolo
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 04.01.2012; Public Library of Science (PLoS)
• Subjects: Animals; Apoptosis; Bacterial infections; Biocompatibility; Biological effects; Biology; Body Size - drug effects; Body Size - physiology; Citric acid; Citric Acid - chemistry; Citric Acid - pharmacology; Citric Acid - toxicity; Deoxyribonucleic acid; DNA; DNA damage; DNA fragmentation; Drosophila; Drosophila melanogaster; Drosophila melanogaster - anatomy & histology; Drosophila melanogaster - drug effects; Drosophila melanogaster - metabolism; Drosophila melanogaster - physiology; Ecological risk assessment; Environmental Exposure; Female; Fertility; Fertility - drug effects; Fertility - physiology; Gene expression; Gold; Gold - chemistry; Gold - pharmacology; Gold - toxicity; Health aspects; Health risks; In Situ Nick-End Labeling; Ingestion; Life span; Longevity - drug effects; Longevity - physiology; Male; Materials Science; Medicine; Metal Nanoparticles - chemistry; Metal Nanoparticles - toxicity; Nanomaterials; Nanoparticles; Nanotechnology; Osmolar Concentration; Physics; Reactive Oxygen Species - metabolism; Reproduction - drug effects; Reproduction - physiology; Surface area; Toxicity; Italy
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0029980

The expected potential benefits promised by nanotechnology in various fields have led to a rapid increase of the presence of engineered nanomaterials in a high number of commercial goods. This is generating increasing questions about possible risks for human health and environment, due to the lack of an in-depth assessment of the physical/chemical factors responsible for their toxic effects. In this work, we evaluated the toxicity of monodisperse citrate-capped gold nanoparticles (AuNPs) of different sizes (5, 15, 40, and 80 nm) in the model organism Drosophila melanogaster, upon ingestion. To properly evaluate and distinguish the possible dose- and/or size-dependent toxicity of the AuNPs, we performed a thorough assessment of their biological effects, using two different dose-metrics. In the first approach, we kept constant the total surface area of the differently sized AuNPs (Total Exposed Surface area approach, TES), while, in the second approach, we used the same number concentration of the four different sizes of AuNPs (Total Number of Nanoparticles approach, TNN). We observed a significant AuNPs-induced toxicity in vivo, namely a strong reduction of Drosophila lifespan and fertility performance, presence of DNA fragmentation, as well as a significant modification in the expression levels of genes involved in stress responses, DNA damage recognition and apoptosis pathway. Interestingly, we found that, within the investigated experimental conditions, the toxic effects in the exposed organisms were directly related to the concentration of the AuNPs administered, irrespective of their size.