The Cyanobacteria Derived Toxin Beta-N-Methylamino-L-Alanine and Amyotrophic Lateral Sclerosis

There is mounting evidence to suggest that environmental factors play a major role in the development of neurodegenerative diseases like ALS (Amyotrophic Lateral Sclerosis). The non-protein amino acid beta-N-methylamino-L-alanine (BMAA) was first associated with the high incidence of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) in Guam, and has been implicated as a potential environmental factor in ALS, Alzheimer’s disease, and other neurodegenerative diseases. BMAA has a number of toxic effects on motor neurons including direct agonist action on NMDA and AMPA receptors, induction of oxidative stress, and depletion of glutathione. As a non-protein amino acid, there is also the strong possibility that BMAA could cause intraneuronal protein misfolding, the hallmark of neurodegeneration. While an animal model for BMAA-induced ALS is lacking, there is substantial evidence to support a link between this toxin and ALS. The ramifications of discovering an environmental trigger for ALS are enormous. In this article, we discuss the history, ecology, pharmacology and clinical ramifications of this ubiquitous, cyanobacteria-derived toxin

Environmental And Occupational Exposures And Amyotrophic Lateral Sclerosis In New England

Background: Recent data provide support for the concept that potentially modifiable exposures are responsible for sporadic amyotrophic lateral sclerosis (ALS). Objective: To evaluate environmental and occupational exposures as risk factors for sporadic ALS. Methods: We performed a case control study of ALS among residents of New England, USA. The analysis compared questionnaire responses from 295 patients with a confirmed ALS diagnosis to those of 225 controls without neurodegenerative illness. Results: Self-reported job-or hobby-related exposure to one or more chemicals, such as pesticides, solvents, or heavy metals, increased the risk of ALS (adjusted OR 2.51; 95% CI 1.64-3.89). Industries with a higher toxicant exposure potential (construction, manufacturing, mechanical, military, or painting) were associated with an elevated occupational risk (adjusted OR 3.95; 95% CI 2.04-8.30). We also identified increases in the risk of ALS associated with frequent participation in water sports, particularly waterskiing (adjusted OR 3.89; 95% C11.97-8.44). Occupation and waterskiing both retained independent statistical significance in a composite model containing age, gender, and smoking status. Conclusions: Our study contributes to a growing body of literature implicating occupational-and hobby-related toxicant exposures in ALS etiology. These epidemiologic study results also provide motivation for future evaluation of water-body-related risk factors. (C) 2017 S. Karger AG, Base

Environmental And Occupational Exposures And Amyotrophic Lateral Sclerosis In New England

Background: Recent data provide support for the concept that potentially modifiable exposures are responsible for sporadic amyotrophic lateral sclerosis (ALS). Objective: To evaluate environmental and occupational exposures as risk factors for sporadic ALS. Methods: We performed a case control study of ALS among residents of New England, USA. The analysis compared questionnaire responses from 295 patients with a confirmed ALS diagnosis to those of 225 controls without neurodegenerative illness. Results: Self-reported job-or hobby-related exposure to one or more chemicals, such as pesticides, solvents, or heavy metals, increased the risk of ALS (adjusted OR 2.51; 95% CI 1.64-3.89). Industries with a higher toxicant exposure potential (construction, manufacturing, mechanical, military, or painting) were associated with an elevated occupational risk (adjusted OR 3.95; 95% CI 2.04-8.30). We also identified increases in the risk of ALS associated with frequent participation in water sports, particularly waterskiing (adjusted OR 3.89; 95% C11.97-8.44). Occupation and waterskiing both retained independent statistical significance in a composite model containing age, gender, and smoking status. Conclusions: Our study contributes to a growing body of literature implicating occupational-and hobby-related toxicant exposures in ALS etiology. These epidemiologic study results also provide motivation for future evaluation of water-body-related risk factors. (C) 2017 S. Karger AG, Base

Medical history of chemotherapy or immunosuppressive drug treatment and risk of amyotrophic lateral sclerosis (ALS)

A recent population-based analysis demonstrated lower risk of the lethal degenerative neuromuscular disease, amyotrophic lateral sclerosis (ALS) associated with history of the use of 'antineoplastic agents' and 'immunosuppressants'. To see if this finding was generalizable to other ALS cohorts, we examined associations between use of these agents and ALS risk in an independent case-control study of n = 414 ALS patients and n = 361 controls in an Eastern US population. Controls were sampled from the general population and among non-neurodegenerative disease patients. A history of chemotherapy treatment was significantly associated with a decreased ALS risk (OR 0.46, 95% CI 0.22-0.89, P = 0.026). We did not observe an association between risk of ALS and immunosuppressant therapy use (OR 0.78, 95% CI 0.50-1.02, P = 0.23). Analyses were adjusted for age, gender, and smoking. Our results support the prior report for chemotherapy treatment and lead to further discussion of the underlying mechanism