Dangers des nanoparticules d´argent (argent colloidal)
De plus en plus d´etudes montrent un effet nocif de nanoparticules d´argent in vitro et in vivo:
Silver nanoparticles affect on gene expression of inflammatory and neurodegenerative responses in mouse brain neural cells
http://www.sciencedirect.com/science/ar ... 5114004058
"AgNPs can cross the cell membrane of mouse neuron cells.
AgNPs increased IL-1β, CXCL13, MARCO and GSS for inflammation and oxidative stress.
AgNPs caused Aβ plaques deposition in neuron cells.
AgNPs induced APP, and reduced NEP and LDLR for Aβ plaque deposition.
It is necessary to take notice of AgNPs effect on neurodegenerative disorders."
Les nanoparticules d´AG peuvent:
*traverser la membrane cellulaire de cellules neuronales de la souris, *induire inflammation (cytokines inflammatoires) et stress oxidatif (radicaux libres),
*causer la deposition de plaque amyloides dans les cellules neuronales
* et peuvent donc potentiellement entrainer des troubles neurodegeneratifs.
Silver nanoparticle induced blood-brain barrier inflammation and increased permeability in primary rat brain microvessel endothelial cells
http://www.ncbi.nlm.nih.gov/pubmed/20713472/
Les nanoparticules d´AG entrainent une inflammation de la barriere hemato-encephalique et augmentent la permeabilite de cellules endotheliales des microvaisseaux dans les cerveaux de rats.
“Further, this study suggests that Ag-NPs may interact with the cerebral microvasculature producing a proinflammatory cascade, if left unchecked; these events may further induce brain inflammation and neurotoxicity.”
Cette etude suggere que les nanoparticules d´AG interagissent avec la microvascularisation cerebrale, entrainant une cascade proinflammatoire, ce qui peut induire inflammation cerebrale et neurotoxicite.
Silver nanoparticles induce tight junction disruption and astrocyte neurotoxicity in a rat blood–brain barrier primary triple coculture model
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4598217/
“Silver nanoparticles (Ag-NPs) can enter the brain and induce neurotoxicity.
After Ag-NPS exposure for 24 hours, the BBB permeability was significantly increased.
Discontinuous TJs were also observed between microvascular endothelial cells
Ag-NPS inhibited the antioxidant defense of the astrocytes
Meanwhile, Ag-NPS induced inflammation and apoptosis.”
Les nanoparticules d´AG peuvent penetrer le cerveau et induire une neurotoxicite.
Apres une exposition de 24 h, la permeabilite de la barriere hemato-encephalique etait significativement augmentee.
Des joints etanches discontinus ont ete observes dans les cellules endotheliales microvasculaires.
Les nanoparticule d´AG inhibent la defense antioxidante des astrocytes.
Distribution, translocation and accumulation of silver nanoparticles in rats
http://www.ncbi.nlm.nih.gov/pubmed/19928170/
"Results indicated that SNPs translocated to the blood circulation and distributed throughout the main organs, especially in the kidney, liver, spleen, brain and lung in the form of particles.
Ultrastructural observations indicate that those SNPs that had accumulated in organs could enter different kinds of cells, such as renal tubular epithelial cells and hepatic cells.
Moreover, SNPs also induced blood-brain barrier (BBB) destruction and astrocyte swelling, and caused neuronal degeneration.
The results suggest more cautions needed in biomedical applications of SNPs, in particular, the long-term uses."
Les nanoparticules d´AG peuvent passer dans la circulation sanguine et se repandre dans les organes principaux, surtout les reins, le foie, le thymus, le cerveau et les poumons sous la forme de particules.
Les nanoparticules d´AG accumulees dans les organes peuvent penetrer tout type de cellules, comme les cellules renales et hepatiques.
De plus, les nanoparticules d´AG induisent une destruction de la barriere hemato-encephalique et un gonflement des astrocytes et causent une degeneration neuronale.
Les resultats suggerent la necessite d´etre prudent dans les applications biomedicales des nanoparticules d´AG, en particulier pour les utilisations a long terme.
Chronic treatment with nanoparticles exacerbate hyperthermia induced blood-brain barrier breakdown, cognitive dysfunction and brain pathology in the rat. Neuroprotective effects of nanowired-antioxidant compound H-290/51.
http://www.ncbi.nlm.nih.gov/pubmed/19928186/
Le traitement chronique avec des nanoparticules d´AG exacerbe la destruction de la barriere hemato-encephalique induite par hyperthermie, une dysfonctionnement cognitif et une pathologie cerebrale chez le rat.