title: Intranasal exposure to silica nanoparticles induces alterations in pro-inflammatory environment of rat brain.
abstract: Silica nanoparticles (SiNPs) are being used increasingly in biomedical and industrial fields; however, their adverse effects on human health have not been fully investigated. In this study, we focused on some of the toxicological aspects of SiNPs by studying oxidative stress and pro-inflammatory responses in the frontal cortex, corpus striatum and hippocampus regions of rat brain. Wistar rats were exposed to SiNPs of size 80 nm and 10 nm at a dose of 150 µg/50 µL phosphate-buffered saline/rat for 30 days. The results indicated a significant increase of lipid peroxide levels and hydrogen peroxide content in various regions of the treated rat brain. Moreover, these changes were accompanied with a significant decrease in the activities of manganese superoxide dismutase, glutathione reductase, catalase and reduced glutathione in different brain regions, suggesting impaired antioxidant defence system. Furthermore, SiNPs exposure not only increased messenger RNA (mRNA) and protein expression of nuclear factor-κB (NF-κB) but also significantly increased the mRNA and protein levels of tumour necrosis factor α (TNF-α), interleukin 1β (IL-1β) and monocyte chemoattractant protein 1 (MCP-1) in different regions of rat brain. Cumulatively, these data suggest that SiNPs induced the activation of NF-κB and increased the expression of TNF-α, IL-1β and MCP-1 in rat brain, possibly via redox-sensitive cellular signalling pathways.
authors.affiliation: 1 Department of Biochemistry, King George's Medical University, Lucknow, Uttar Pradesh, India.
authors.forename: Arshiya
authors.initials: A
authors.lastname: Parveen
authors.affiliation: 1 Department of Biochemistry, King George's Medical University, Lucknow, Uttar Pradesh, India.
authors.forename: Syed Husain Mustafa
authors.initials: SH
authors.lastname: Rizvi
authors.affiliation: 2 Fibre Toxicology Division, CSIR-Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India.
authors.lastname: Sushma
authors.affiliation: 3 Department of Biochemistry, Era's Lucknow Medical College & Hospital, Lucknow, Uttar Pradesh, India.
authors.forename: Farzana
authors.initials: F
authors.lastname: Mahdi
authors.affiliation: 2 Fibre Toxicology Division, CSIR-Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India.
authors.forename: Iqbal
authors.initials: I
authors.lastname: Ahmad
authors.affiliation: 3 Department of Biochemistry, Era's Lucknow Medical College & Hospital, Lucknow, Uttar Pradesh, India.
authors.forename: Prem Prakhash
authors.initials: PP
authors.lastname: Singh
authors.affiliation: 1 Department of Biochemistry, King George's Medical University, Lucknow, Uttar Pradesh, India.
authors.forename: Abbas Ali
authors.initials: AA
authors.lastname: Mahdi
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D001921:Brain / Q000187:drug effects*; D003342:Corpus Striatum / Q000737:chemistry / Q000187:drug effects; D005625:Frontal Lobe / Q000737:chemistry / Q000187:drug effects; D006624:Hippocampus / Q000737:chemistry / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000032:analysis; D007249:Inflammation / Q000139:chemically induced; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D053758:Nanoparticles / Q000008:administration & dosage / Q000009:adverse effects*; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D012822:Silicon Dioxide / Q000008:administration & dosage / Q000009:adverse effects*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D012822:Silicon Dioxide; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase
keywords: Silica nanoparticles; neuroinflammation; oxidative stress