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Kupffer cells are central in the removal of nanoparticles from the organism.

Sadauskas E, Wallin H, Stoltenberg M, Vogel U, Doering P, Larsen A, Danscher G - Part Fibre Toxicol (2007)

Bottom Line: IV injections resulted in a rapid accumulation/clustering of nanoparticles in these liver macrophages, while the uptake in spleen macrophages was moderate.Ultrastructurally, the AMG silver enhanced nanocrystals were found in lysosome-like organelles of the Kupffer cells and other macrophages wherever located.Accumulations of gold nanoparticles were not found in any other organs analysed, i.e. kidneys, brain, lungs, adrenals, ovaries, placenta, and fetal liver, and the control animals were all void of AMG staining.Our results suggest that: (1) inert gold nanoparticles do not penetrate cell membranes by non-endocytotic mechanisms, but are rather taken up by endocytosis; (2) gold nanoparticles, independent of size, are taken up primarily by Kupffer cells in the liver and secondarily by macrophages in other places; (3) gold nanoparticles do not seem to penetrate the placenta barrier; (4) the blood-brain barrier seems to protect the central nervous system from gold nanoparticles; (5) 2 nanometer gold particles seem to be removed not only by endocytosis by macrophages, and we hypothesize that part of these tiny nanoparticles are released into the urine as a result of simple filtration in the renal glomeruli.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Neurobiology, Institute of Anatomy, University of Aarhus, Building 1233/1234, Wilhelm Meyers Allé, DK-8000 Aarhus C, Denmark. gd@neuro.au.dk.

ABSTRACT

Background: The study aims at revealing the fate of nanoparticles administered intravenously and intraperitoneally to adult female mice, some of which were pregnant. Gold nanoparticles were chosen as a model because these particles have been found to be chemically inert and at the same time are easily traced by autometallography (AMG) at both ultrastructural and light microscopic levels.

Results: Gold nanoparticles were injected intravenously (IV) or intraperitoneally (IP) and traced after 1, 4 or 24 hours. For IV injections 2 and 40 nm particles were used; for IP injections 40 nm particles only. The injected nanoparticles were found in macrophages only, and at moderate exposure primarily in the Kupffer cells in the liver. IV injections resulted in a rapid accumulation/clustering of nanoparticles in these liver macrophages, while the uptake in spleen macrophages was moderate. IP injections were followed by a delayed uptake in the liver and included a moderate uptake in macrophages located in mesenteric lymph nodes, spleen and small intestine. Ultrastructurally, the AMG silver enhanced nanocrystals were found in lysosome-like organelles of the Kupffer cells and other macrophages wherever located.Accumulations of gold nanoparticles were not found in any other organs analysed, i.e. kidneys, brain, lungs, adrenals, ovaries, placenta, and fetal liver, and the control animals were all void of AMG staining.

Conclusion: Our results suggest that: (1) inert gold nanoparticles do not penetrate cell membranes by non-endocytotic mechanisms, but are rather taken up by endocytosis; (2) gold nanoparticles, independent of size, are taken up primarily by Kupffer cells in the liver and secondarily by macrophages in other places; (3) gold nanoparticles do not seem to penetrate the placenta barrier; (4) the blood-brain barrier seems to protect the central nervous system from gold nanoparticles; (5) 2 nanometer gold particles seem to be removed not only by endocytosis by macrophages, and we hypothesize that part of these tiny nanoparticles are released into the urine as a result of simple filtration in the renal glomeruli.

No MeSH data available.


Related in: MedlinePlus

Electron micrographs showing AMG enhanced clustered gold nanoparticles in the lysosomes of a Kupffer cell (a) and a spleen macrophage (b). The animal was exposed to 40 nm gold nanoparticles intravenously and allowed to survive for 24 hours. Scalebars = 2 μm.
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Figure 2: Electron micrographs showing AMG enhanced clustered gold nanoparticles in the lysosomes of a Kupffer cell (a) and a spleen macrophage (b). The animal was exposed to 40 nm gold nanoparticles intravenously and allowed to survive for 24 hours. Scalebars = 2 μm.

Mentions: Independent of exposure, the gold nanoparticles were found ultrastructurally to accumulate in lysosome-like structures of the macrophages supporting the notion that nanoparticles are taken up by endocytosis (Fig. 2). Careful scanning of AMG silver enhanced sections from kidneys, brain, lungs, adrenals and ovaries of both IP and IV injected animals did not reveal accumulation of nanoparticles in these organs.


Kupffer cells are central in the removal of nanoparticles from the organism.

Sadauskas E, Wallin H, Stoltenberg M, Vogel U, Doering P, Larsen A, Danscher G - Part Fibre Toxicol (2007)

Electron micrographs showing AMG enhanced clustered gold nanoparticles in the lysosomes of a Kupffer cell (a) and a spleen macrophage (b). The animal was exposed to 40 nm gold nanoparticles intravenously and allowed to survive for 24 hours. Scalebars = 2 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2146996&req=5

Figure 2: Electron micrographs showing AMG enhanced clustered gold nanoparticles in the lysosomes of a Kupffer cell (a) and a spleen macrophage (b). The animal was exposed to 40 nm gold nanoparticles intravenously and allowed to survive for 24 hours. Scalebars = 2 μm.
Mentions: Independent of exposure, the gold nanoparticles were found ultrastructurally to accumulate in lysosome-like structures of the macrophages supporting the notion that nanoparticles are taken up by endocytosis (Fig. 2). Careful scanning of AMG silver enhanced sections from kidneys, brain, lungs, adrenals and ovaries of both IP and IV injected animals did not reveal accumulation of nanoparticles in these organs.

Bottom Line: IV injections resulted in a rapid accumulation/clustering of nanoparticles in these liver macrophages, while the uptake in spleen macrophages was moderate.Ultrastructurally, the AMG silver enhanced nanocrystals were found in lysosome-like organelles of the Kupffer cells and other macrophages wherever located.Accumulations of gold nanoparticles were not found in any other organs analysed, i.e. kidneys, brain, lungs, adrenals, ovaries, placenta, and fetal liver, and the control animals were all void of AMG staining.Our results suggest that: (1) inert gold nanoparticles do not penetrate cell membranes by non-endocytotic mechanisms, but are rather taken up by endocytosis; (2) gold nanoparticles, independent of size, are taken up primarily by Kupffer cells in the liver and secondarily by macrophages in other places; (3) gold nanoparticles do not seem to penetrate the placenta barrier; (4) the blood-brain barrier seems to protect the central nervous system from gold nanoparticles; (5) 2 nanometer gold particles seem to be removed not only by endocytosis by macrophages, and we hypothesize that part of these tiny nanoparticles are released into the urine as a result of simple filtration in the renal glomeruli.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Neurobiology, Institute of Anatomy, University of Aarhus, Building 1233/1234, Wilhelm Meyers Allé, DK-8000 Aarhus C, Denmark. gd@neuro.au.dk.

ABSTRACT

Background: The study aims at revealing the fate of nanoparticles administered intravenously and intraperitoneally to adult female mice, some of which were pregnant. Gold nanoparticles were chosen as a model because these particles have been found to be chemically inert and at the same time are easily traced by autometallography (AMG) at both ultrastructural and light microscopic levels.

Results: Gold nanoparticles were injected intravenously (IV) or intraperitoneally (IP) and traced after 1, 4 or 24 hours. For IV injections 2 and 40 nm particles were used; for IP injections 40 nm particles only. The injected nanoparticles were found in macrophages only, and at moderate exposure primarily in the Kupffer cells in the liver. IV injections resulted in a rapid accumulation/clustering of nanoparticles in these liver macrophages, while the uptake in spleen macrophages was moderate. IP injections were followed by a delayed uptake in the liver and included a moderate uptake in macrophages located in mesenteric lymph nodes, spleen and small intestine. Ultrastructurally, the AMG silver enhanced nanocrystals were found in lysosome-like organelles of the Kupffer cells and other macrophages wherever located.Accumulations of gold nanoparticles were not found in any other organs analysed, i.e. kidneys, brain, lungs, adrenals, ovaries, placenta, and fetal liver, and the control animals were all void of AMG staining.

Conclusion: Our results suggest that: (1) inert gold nanoparticles do not penetrate cell membranes by non-endocytotic mechanisms, but are rather taken up by endocytosis; (2) gold nanoparticles, independent of size, are taken up primarily by Kupffer cells in the liver and secondarily by macrophages in other places; (3) gold nanoparticles do not seem to penetrate the placenta barrier; (4) the blood-brain barrier seems to protect the central nervous system from gold nanoparticles; (5) 2 nanometer gold particles seem to be removed not only by endocytosis by macrophages, and we hypothesize that part of these tiny nanoparticles are released into the urine as a result of simple filtration in the renal glomeruli.

No MeSH data available.


Related in: MedlinePlus