Browse by author
Lookup NU author(s): Dr Fabio Gualtieri
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
An early but transient decrease in oxygen availability occurs during experimentally induced seizures. Using pimonidazole, which probes hypoxic insults, we found that by increasing the duration of pilocarpine-induced status epilepticus (SE) from 30 to 120 min, counts of pimonidazole-immunoreactive neurons also increased (P < 0.01, 120 vs 60 and 30 min). All the animals exposed to SE were immunopositive to pimonidazole, but a different scenario emerged during epileptogenesis when a decrease in pimonidazole-immunostained cells occurred from 7 to 14 days, so that only 1 out of 4 rats presented with pimonidazole-immunopositive cells. Pimonidazole-immunoreactive cells robustly reappeared at 21 days post-SE induction when all animals (7 out of 7) had developed spontaneous recurrent seizures. Specific neuronal markers revealed that immunopositivity to pimonidazole was present in cells identified by neuropeptide Y (NPY) or somatostatin antibodies. At variance, neurons immunopositive to parvalbumin or cholecystokinin were not immunopositive to pimonidazole. Pimonidazole-immunopositive neurons expressed remarkable immunoreactivity to hypoxia-inducible factor 1α (HIF-1α). Interestingly, surgical samples obtained from pharmacoresistant patients showed neurons co-labeled by HIF-1α and NPY antibodies. These interneurons, along with parvalbumin-positive interneurons that were negative to HIF-1α, showed immunopositivity to markers of cell damage, such as high-mobility group box 1 in the cytoplasm and cleaved caspase-3 in the nucleus. These findings suggest that interneurons are continuously endangered in rodent and human epileptogenic tissue. The presence of hypoxia and cell damage markers in NPY interneurons of rats and patients presenting with recurrent seizures indicates a mechanism of selective vulnerability in a specific neuronal subpopulation.
Author(s): Gualtieri F, Marinelli C, Longo D, Pugnaghi M, Nichelli PF, Meletti S, Biagini G
Publication type: Article
Publication status: Published
Journal: NeuroMolecular Medicine
Year: 2013
Volume: 15
Issue: 1
Pages: 133-146
Print publication date: 01/03/2013
ISSN (print): 1535-1084
ISSN (electronic): 1559-1174
Publisher: Humana Press, Inc.
URL: http://dx.doi.org/10.1007/s12017-012-8203-0
DOI: 10.1007/s12017-012-8203-0
PubMed id: 23073716
Altmetrics provided by Altmetric