title: Concentration-dependent, size-independent toxicity of citrate capped AuNPs in Drosophila melanogaster.
abstract: 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.
authors.affiliation: Italian Institute of Technology, Center for Bio-Molecular Nanotechnologies@UniLe, Arnesano (Lecce), Italy. giuseppe.vecchio@iit.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Vecchio
authors.forename: Antonio
authors.initials: A
authors.lastname: Galeone
authors.forename: Virgilio
authors.initials: V
authors.lastname: Brunetti
authors.forename: Gabriele
authors.initials: G
authors.lastname: Maiorano
authors.forename: Stefania
authors.initials: S
authors.lastname: Sabella
authors.forename: Roberto
authors.initials: R
authors.lastname: Cingolani
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Pompa
mesh_terms: D000818:Animals; D049628:Body Size / Q000187:drug effects / Q000502:physiology*; D019343:Citric Acid / Q000737:chemistry / Q000494:pharmacology / Q000633:toxicity*; D004331:Drosophila melanogaster / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D004781:Environmental Exposure; D005260:Female; D005298:Fertility / Q000187:drug effects / Q000502:physiology; D006046:Gold / Q000737:chemistry* / Q000494:pharmacology / Q000633:toxicity; D020287:In Situ Nick-End Labeling; D008136:Longevity / Q000187:drug effects / Q000502:physiology; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D009994:Osmolar Concentration; D017382:Reactive Oxygen Species / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects / Q000502:physiology
chemical_list: D017382:Reactive Oxygen Species; D019343:Citric Acid; D006046:Gold