Giuseppe Vecchio's Posts (7)

Full member
Drosophila was the most important model organism used in the fields of medicine and biology over the last century. Recently, Drosophila was successfully used in several studies in the field of nanotoxicology. However, only a part of its potential has been exploited in this field until now. In fact, apart from macroscopic observations of the effect due to the interaction between nanomaterials and living organism (i.e. lifespan, fertility, phenotypic aberrations, etc.), Drosophila has the potential to be a very useful tool to deeply analyze the molecular pathways involved in response to the interactions at nano-bio level. The aim of this editorial is to encourage the use of Drosophila by the different research groups working in the fields of nanotoxicology and nanomedicine, in order to define the effects induced by nanomaterials at molecular level for their subsequent exploitation in the field of nanomedicine.


Read More: http://informahealthcare.com/eprint/xIb4Kcc9Gs5INJZgynGc/full
Read more…
Full member

The continuous increasing of engineered nanomaterials (ENMs) in our environment, their combinatorial diversity, and the associated genotoxic risks, highlight the urgent need to better define the possible toxicological effects of ENMs. In this context, we present a new high-throughput screening (HTS) platform based on the cytokinesis-block micronucleus (CBMN) assay, lab-on-chip cell sorting, and automated image analysis. This HTS platform has been successfully applied to the evaluation of the cytotoxic and genotoxic effects of silver nanoparticles (AgNPs) and silica nanoparticles (SiO2NPs). In particular, our results demonstrate the high cyto- and genotoxicity induced by AgNPs and the biocompatibility of SiO2NPs, in primary human lymphocytes. Moreover, our data reveal that the toxic effects are also dependent on size, surface coating, and surface charge. Most importantly, our HTS platform shows that AgNP-induced genotoxicity is lymphocyte sub-type dependent and is particularly pronounced in CD2+ and CD4+ cells.

Full Article

Read more…
Full member

Abstract

In this work, we propose a quantitative assessment of nanoparticles toxicity in vivo. We show a quantitative ranking of several types of nanoparticles (AuNPs, AgNPs, cadmium-based QDs, cadmium-free QDs, and iron oxide NPs, with different coating and/or surface chemistries), providing a categorization of their toxicity outcomes. This strategy may offer an innovative high-throughput screening tool of nanomaterials, of potential and broad interest to the nanoscience community.

Full Article

Read more…
Full member

Abstract

The peculiar physical/chemical characteristics of engineered nanomaterials have led to a rapid increase of nanotechnology-based applications in many fields. However, before exploiting their huge and wide potential, it is necessary to assess their effects upon interaction with living systems. In this context, the screening of nanomaterials to evaluate their possible toxicity and understand the underlying mechanisms currently represents a crucial opportunity to prevent severe harmful effects in the next future. In this work we show the in vivo toxicity of gold nanoparticles (Au NPs) in Drosophila melanogaster, highlighting significant genotoxic effects and, thus, revealing an unsettling aspect of the long-term outcome of the exposure to this nanomaterial. After the treatment with Au NPs, we observed dramatic phenotypic modifications in the subsequent generations of Drosophila, demonstrating their capability to induce mutagenic effects that may be transmitted to the descendants. Noteworthy, we were able to obtain the first nanomaterial-mutated organism, named NM-mut. Although these results sound alarming, they underline the importance of systematic and reliable toxicology characterizations of nanomaterials and the necessity of significant efforts by the nanoscience community in designing and testing suitable nanoscale surface engineering/coating to develop biocompatible nanomaterials with no hazardous effects for human health and environment.


From the Clinical Editor

While the clinical application of nanomedicine is still in its infancy, the rapid evolution of this field will undoubtedly result in a growing number of clinical trials and eventually in human applications. The interactions of nanoparticles with living organisms determine their toxicity and long-term safety, which must be properly understood prior to large-scale applications are considered. The paper by Dr. Vecchio is the first ever demonstration of mutagenesis resulting in clearly observable phenotypic alterations and the generation of nano-mutants as a result of exposure to citrate-surfaced gold nanoparticles in drosophila. These groundbreaking results are alarming, but represent a true milestone in nanomedicine and serve as a a reminder and warning about the critical importance of "safety first" in biomedical science.

http://dx.doi.org/10.1016/j.nano.2011.11.001

Read more…
Full member

Semiconductor nanocrystals, or Quantum Dots (QDs), have gained considerable attention due to their unique size-dependent optical and electronic properties that make them attractive for a wide range of applications, including biology and nanomedicine. Their widespread use, however, poses urgent questions about their potential toxicity, especially because of their heavy metal composition that could cause harmful effects to human health and environment. In this work, we evaluated in vivo the long-term toxicity of CdSe–ZnS QDs with different surface coatings, probing oral administration in the model system Drosophila melanogaster. In particular, we found that all the differently coated QDs significantly affect the lifespan of treated Drosophila populations and induce a marked increase in reactive oxygen species (ROS) levels. Furthermore, we observed that these QDs induce severe genotoxic effects and increased rate of apoptosis in Drosophila haemocytes. These toxic effects were found to be mainly related to the in vivo degradation of QDs with consequent release of Cd2+ ions, while the coating of QDs can modulate their bioaccumulation in the organism, partly decreasing their overall toxicity.

 DOI: 10.1039/C2NR31826A

Read more…
Full member

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.

doi:10.1371/journal.pone.0029980

Read more…