Title |
Cu/Zn superoxide dismutase expression in the postnatal rat brain following an excitotoxic injury
|
---|---|
Published in |
Journal of Neuroinflammation, June 2005
|
DOI | 10.1186/1742-2094-2-12 |
Pubmed ID | |
Authors |
Hugo Peluffo, Laia Acarin, Maryam Faiz, Bernardo Castellano, Berta Gonzalez |
Abstract |
BACKGROUND: In the nervous system, as in other organs, Cu/Zn superoxide dismutase (Cu/Zn SOD) is a key antioxidant enzyme involved in superoxide detoxification in normal cellular metabolism and after cell injury. Although it has been suggested that immature brain has a different susceptibility to oxidative damage than adult brain, the distribution and cell-specific expression of this enzyme in immature brain and after postnatal brain damage has not been documented. METHODS: In this study, we used immunohistochemistry and western blot to analyze the expression of Cu/Zn SOD in intact immature rat brain and in immature rat brain after an NMDA-induced excitotoxic cortical injury performed at postnatal day 9. Double immunofluorescence labelling was used to identify Cu/Zn SOD-expressing cell populations. RESULTS: In intact immature brain, Cu/Zn SOD enzyme was widely expressed at high levels in neurons mainly located in cortical layers II, III and V, in the sub-plate, in the pyriform cortex, in the hippocampus, and in the hypothalamus. Glial fibrillary acidic protein-positive cells only showed Cu/Zn SOD expression in the glia limitans and in scattered cells of the ventricle walls. No expression was detected in interfascicular oligodendroglia, microglia or endothelial cells. Following excitotoxic damage, neuronal Cu/Zn SOD was rapidly downregulated (over 2-4 hours) at the injection site before neurodegeneration signals and TUNEL staining were observed. Later, from 1 day post-lesion onward, an upregulation of Cu/Zn SOD was found due to increased expression in astroglia. A further increase was observed at 3, 5 and 7 days that corresponded to extensive induction of Cu/Zn SOD in highly reactive astrocytes and in the astroglial scar. CONCLUSION: We show here that, in the intact immature brain, the expression of Cu/Zn SOD was mainly found in neurons. When damage occurs, a strong and very rapid downregulation of this enzyme precedes neuronal degeneration, and is followed by an upregulation of Cu/Zn SOD in astroglial cells. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Spain | 2 | 6% |
United States | 1 | 3% |
Italy | 1 | 3% |
Unknown | 29 | 88% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Researcher | 8 | 24% |
Student > Ph. D. Student | 7 | 21% |
Student > Master | 6 | 18% |
Professor > Associate Professor | 2 | 6% |
Professor | 2 | 6% |
Other | 4 | 12% |
Unknown | 4 | 12% |
Readers by discipline | Count | As % |
---|---|---|
Agricultural and Biological Sciences | 14 | 42% |
Medicine and Dentistry | 6 | 18% |
Neuroscience | 3 | 9% |
Psychology | 1 | 3% |
Environmental Science | 1 | 3% |
Other | 2 | 6% |
Unknown | 6 | 18% |