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- Sharma, Hari Shanker, et al.
(författare)
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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
- 2009
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Ingår i: Journal of Nanoscience and Nanotechnology. - 1533-4880 .- 1533-4899. ; 9:8, s. 5073-5090
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Tidskriftsartikel (refereegranskat)abstract
- The possibility that chronic exposure of nanoparticles may alter stress reaction and brain pathology following hyperthermia was examined in a rat model. Engineered nanoparticles from Ag or M Cu (approximate to 50-60 nm) were administered (30 mg/kg, i.p.) once daily for 1 week in young male rats. M On the 8th day these animals were subjected to 4 h heat stress at 38 degrees C in a BOD incubator. In these animals stress symptoms, blood-brain barrier (BBB) permeability, cognitive and motor functions and brain pathology were examined. Subjection of nanoparticle treated rats to heat stress showed exacerbation of stress symptoms i.e., hyperthermia, salivation and prostration and exhibited greater BBB disruption, brain edema formation, impairment of cognitive and motor functions M and brain damage compared to normal animals. This enhanced brain pathology in heat stress was most marked in animals that received Ag nanoparticles compared to Cu treatment. Treatment with antioxidant compound H-290/51 either 30 min or 60 min after heat stress did not alter hyperthermia M induce brain pathology in nanoparticle treated rats. Whereas, administration of nanowired-H-290/51 after 30 min or 60 min heat stress markedly attenuated BBB disruption, sensory motor function and brain pathology. These results suggest that chronic nanoparticles treatment exacerbate hyperthermia induced brain pathology that is significantly attenuated by nanowired but not normal H-290/51 compound. Taken together, our observations suggest that nano-wired drug delivery of H-290/51 is a promising approach to induce neuroprotection in hyperthermia induced brain pathology, not reported earlier.
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| 2. |
- Sharma, Hari S., et al.
(författare)
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Influence of Engineered Nanoparticles from Metals on the Blood-Brain Barrier Permeability, Cerebral Blood Flow, Brain Edema and Neurotoxicity : An Experimental Study in the Rat and Mice Using Biochemical and Morphological Approaches
- 2009
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Ingår i: Journal of Nanoscience and Nanotechnology. - 1533-4880 .- 1533-4899. ; 9:8, s. 5055-5072
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Tidskriftsartikel (refereegranskat)abstract
- Influence of nanoparticles on brain function following in vivo exposures is not well known. Depending on the magnitude and intensity of nanoparticle exposure from the environment, food and/or water source, neuronal function could be affected and may lead to neurotoxicity and neuropathology. This hypothesis was examined in present investigation using systemic or intracerebroventricular administration of engineered nanoparticles from metals, i.e., Al, Ag and Cu (approximate to 50 to 60 nm) on neurotoxicity in rats and mice. Intraperitoneal (50 mg/kg), intravenous (30 mg/kg), intracarotid (2.5 mg/kg) or intracerebroventricular administration (20 mu g) of nanoparticles significantly altered the blood-brain barrier (BBB) function to Evans blue and radioiodine in several regions of the brain and spinal cord at 24 h after their administration. Marked decreases in local cerebral blood flow (CBF) and pronounced brain edema was seen in regional areas associated with BBB leakage. Neuronal cell injuries, glial cell activation, heat shock protein (HSP) upregulation and loss of myelinated fibers are quite common in effected brain areas. The observed pathological changes were most pronounced in mice compared to rats. Exposures to Cu and Ag nanoparticles showed most marked effects on brain pathology when administered into systemic circulation or into the brain ventricular spaces as compared to Al nanoparticles. Our results are the first to show that nanoparticles from metals are able to induce selective and specific neurotoxicity that depends on the type of metals, route of administration and the species used.
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