Toggle Main Menu Toggle Search

Open Access padlockePrints

Cu/Zn superoxide dismutase (SOD1) mutations associated with familial amyotrophic lateral sclerosis (ALS) affect cellular free radical release in the presence of oxidative stress

Lookup NU author(s): Dr Mark Cookson, Fiona Menzies, Dr Philip Manning, Dr Christopher Eggett, Emeritus Professor Calum McNeil, Professor Pamela Shaw

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

Introduction: The exact molecular mechanisms by which mutations in Cu/Zn superoxide dismutase (SOD1) cause motor neuron injury remain incompletely understood, though a body of evidence suggests that the mutant protein exerts a cell-specific toxic gain of function. The role of nitric oxide (NO) in SOD1-related motor neuron injury has been particularly controversial. Theoretically, there are arguments to suggest that NO may exert an important role in motor neuron injury, but there is relatively little direct experimental support for this hypothesis. Objectives: The present study aimed to examine further the potential role for NO in motor neuron injury caused by mutant SOD1. Method: We have generated a cellular model of familial amyotrophic lateral sclerosis (ALS) by stably transfecting NSC34 cells with one of three mutant forms of SOD1 (G93A, G37R, I113T). In the presence of mutant SOD1, NSC34 cells show increased cell death following oxidative stress induced by serum withdrawal. This model of motor neuron death involves cellular release of superoxide and NO radicals, which were directly measured in real time using microelectrode biosensors. Results: The expression of both normal and mutant SOD1 decreased the measured extracellular superoxide release, but had divergent effects on the measured release of NO. Normal SOD1 increased the measured NO release, whereas cells expressing mutant SOD1 released less NO. Co-administration of two different nitric oxide synthase inhibitors (L-NAME and L-N-methyl arginine) did show some neuroprotective effect, but this was only partial, and the effect was more marked using nuclear integrity as a measure of cell viability, rather than MTT conversion. Cells expressing mutant SOD1 were, however, more sensitive to toxicity induced by extrinsic exposure to NO, using a slow-release NO donor. Conclusion: NO is likely to contribute to motor neuron injury, but this does not fully account for all the cellular toxic effects of mutant SOD1.


Publication metadata

Author(s): Cookson MR, Menzies FM, Manning P, Eggett CJ, Figlewicz DA, McNeil CJ, Shaw PJ

Publication type: Article

Publication status: Published

Journal: Amyotrophic Lateral Sclerosis and Other Motor Neuron Disorders

Year: 2002

Volume: 3

Issue: 2

Pages: 75-85

ISSN (print): 1748-2968

ISSN (electronic):

Publisher: Informa Healthcare

URL: http://dx.doi.org/10.1080/146608202760196048

DOI: 10.1080/146608202760196048


Altmetrics

Altmetrics provided by Altmetric


Actions

Find at Newcastle University icon    Link to this publication


Share