[Environmental factors in ALS].
ALS is likely to be a disorder of multifactorial origin. Among all the factors that may increase the risk of ALS, environmental ones are being studied for many years, but in the recent years, several advances have pointed to a new interest in their potential involvement in the disease process, especially for the cyanotoxin BMAA. Food containing BMAA has been found on Guam, a well-known focus of ALS/parkinsonism/dementia and high levels of BMAA have been identified into the brain of these patients. The BMAA cyanotoxin is potentially ubiquitous and have also been found into the food of patients who died from ALS both in Europe and USA. BMAA can be wrongly integrated into the protein structure during mRNA traduction, competing with serine. This may induce abnormal protein folding and a subsequent cell death. Heavy metals, such as lead or mercury may be directly toxic for neuronal cells. Several works have suggested an increased risk of ALS in individuals chronically exposed to these metals. Exposure to pesticides has been suggested to be linked to an increased risk of developing ALS. The mechanism of their toxicity is likely to be mediated by paraoxonases. These proteins are in charge of detoxifying the organism from toxins, and particularly organophosphates. To date, there are insufficient scientific data to suggest that exposure to electromagnetic fields may increase the risk of having ALS. We are particularly missing longitudinal cohorts to demonstrate that risk.
Hôpital Gui-de-Chauliac, service de neurologie, clinique du motoneurone, Inserm 1051, 34925 Montpellier cedex 5, France.
Raul
R
Juntas-Morales
Hôpital Gui-de-Chauliac, service de neurologie, clinique du motoneurone, Inserm 1051, 34925 Montpellier cedex 5, France.
Nicolas
N
Pageot
CHRU de Tours, centre SLA, service de neurologie et neurophysiologie clinique, UMR Inserm U930, 37000 Tours, France.
Philippe
P
Corcia
Hôpital Gui-de-Chauliac, service de neurologie, clinique du motoneurone, Inserm 1051, 34925 Montpellier cedex 5, France. Electronic address: w-camu@chu-montpellier.fr.
William
W
Camu
D000599:Amino Acids, Diamino / Q000633:toxicity; D000690:Amyotrophic Lateral Sclerosis / Q000209:etiology*; D000087522:Cyanobacteria Toxins; D004777:Environment; D006801:Humans
D000599:Amino Acids, Diamino; D000087522:Cyanobacteria Toxins; C001824:beta-N-methylamino-L-alanine