ORIGINAL ARTICLE Amyotrophic Lateral Sclerosis (ALS) and extremely-low frequency (ELF) magnetic fields: A study in the SOD-1 transgenic mouse model FLORENCE POULLETIER DE GANNES 1 , GILLES RUFFIE ´ 1 , MURIELLE TAXILE 1 , ELODIE LADEVE ` ZE 1 , ANNABELLE HURTIER 1 , EMMANUELLE HARO 1 , SE ´ BASTIEN DULEU 2 , RENAUD CHARLET DE SAUVAGE 1 , BERNARD BILLAUDEL 1 , MICHEL GEFFARD 1,2 , BERNARD VEYRET 1,3 & ISABELLE LAGROYE 1,3 1 University of Bordeaux 1, IMS laboratory, Bioelectromagnetics group, ENSCPB, 16 Avenue Pey Berland, Pessac, France, 2 Gemacbio, Cenon, France, and 3 Bioelectromagnetics laboratory, E ´ cole Pratique des Hautes E ´ tudes, ENSCPB, 16 Avenue Pey Berland, Pessac, France Abstract There is some evidence from epidemiological studies of an association between occupational exposure to electromagnetic fields and Amyotrophic Lateral Sclerosis (ALS). Our aim was to perform, for the first time, an animal study in a controlled magnetic environment. We used the SOD-1 mouse model to assess the possible effect of ELF magnetic fields on development of the disease. Seven mice per group were exposed to 50 Hz magnetic fields at two intensities (100 and 1000 mT rms ) before the onset of the clinical signs of ALS. Exposure lasted 7 weeks, and body weight, motor performance and life span were monitored. Our results did not reveal any evidence of a link between ELF exposure and ALS in this transgenic animal model. Key words: Amyotrophic lateral sclerosis, Magnetic Field, SOD-1 transgenic mice Introduction Although several hypothesis concerning the patho- genesis of Amyotrophic Lateral Sclerosis (ALS) have been generated, the aetiology of the vast majority of cases is unknown, although electrical exposure has been cited as an possible environmental risk factor. Haynal & Regli were the first to raise the hypothesis that exposure to ELF electromagnetic fields was linked to ALS in 1964 (1). Nine out of 73 patients with ALS had worked in contact with electricity, compared to 5 out of 150 controls, giving, according to Deapen & Henderson (2) an odds ratio of 4.1. Since that time, other epidemio- logical studies have reported significant relative risk or odds-ratios in the range of 1.3 to 4.6 (38), while a few studies found little or no association (9,10). Taken together, the studies on ALS suggest an increased risk in EMF-exposed subjects. However, in these studies, lack of assessment of magnetic field exposure at the workplace and possible confounding by electric shocks, were the major limitations. Therefore, pending further well-designed epidemio- logical studies, there was a need for confirmation from additional, specifically-designed laboratory ex- periments. Our aim was to perform, for the first time, an animal study in a controlled magnetic environment. We used the SOD-1 mouse model, which is cur- rently the most accurate animal model of ALS, to assess the possible effect of ELF magnetic fields on the development of disease. Mice were exposed for 2 hours/day, 5 days/week for 7 weeks to 50 Hz magnetic fields at two different magnetic flux densities (100 and 1000 mT). These exposure levels were chosen on the basis of the European recom- mendation setting limits of 100 mT for public exposure and 500 mT for the workplace. 1 The development of ALS was scored by monitoring mean body weight, motor function (Rotarod test), and life span. 1 1999/519/EC: Council Recommendation of 12 July 1999 on the limitation of exposure of the general public to electromagnetic fields (0 Hz to 300 GHz). Official Journal L199, 30/07/1999, p.00590070. Correspondence: Isabelle Lagroye, IMS laboratory, Bioelectromagnetics group, ENSCPB site, 16 avenue Pey -Berland, 33607 Pessac cedex, France. Phone: 33 5 40 00 28 21 Fax: 33 5 40 00 66 31. E-mail: isabelle.lagroye@ims-bordeaux.fr (Received 28 January 2008; accepted 19 June 2008) Amyotrophic Lateral Sclerosis. 2009; 10: 370373 ISSN 1748-2968 print/ISSN 1471-180X online # 2009 Informa UK Ltd. (Informa Healthcare, Taylor & Francis AS) DOI: 10.3109/17482960802320396 Amyotroph Lateral Scler Downloaded from informahealthcare.com by 78.36.8.226 on 05/20/14 For personal use only.