New researched published in Nature Nanotechnology shows that nanoparticles can damage DNA and chromosomes in cells, across an intact barrier of other cells. The research suggests that nanoparticles could cause cancer, or even birth defects, without crossing biological barriers. It highlights the need for precautionary management of nanotechnology risks.
Traditionally risk is considered a factor of ‘hazard’ and ‘exposure’. Yet this research suggests that when it comes to nanoparticles, we need to dramatically rethink our understanding of the ‘exposure’ required to cause harm.
The study authors state: “We suggest that an evaluation of nanoparticle safety should not rely on whether they fail to gain access to privileged sites. Instead there should also be an evaluation of their genotoxic potential for both direct and indirect effects to avoid any potential risks to targets on the distal side of cellular barriers.”
Nanoparticles can cause DNA damage across a cellular barrier
Abstract: The increasing use of nanoparticles in medicine has raised concerns over their ability to gain access to privileged sites in the body. Here, we show that cobalt–chromium nanoparticles (29.5 6.3 nm in diameter) can damage human fibroblast cells across an intact cellular barrier without having to cross the barrier. The damage is mediated by a novel mechanism involving transmission of purine nucleotides (such as ATP) and intercellular signalling within the barrier through connexin gap junctions or hemichannels and pannexin channels. The outcome, which includes DNA damage without significant cell death, is different from that observed in cells subjected to direct exposure to nanoparticles. Our results suggest the importance of indirect effects when evaluating the safety of nanoparticles. The potential damage to tissues located behind cellular barriers needs to be considered when using nanoparticles for targeting diseased states.
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