Environmental Neurotoxin β-N-Methylamino-L-alanine (BMAA) as a Widely Occurring Putative Pathogenic Factor in Neurodegenerative Diseases

In the present review we have discussed the occurrence of beta-N-methylamino-L-alanine (BMAA) and its natural isomers, and the organisms and sample types in which the toxin(s) have been detected. Further, the review discusses general pathogenic mechanisms of neurodegenerative diseases, and how modes of action of BMAA fit in those mechanisms. The biogeography of BMAA occurrence presented here contributes to the planning of epidemiological research based on the geographical distribution of BMAA and human exposure. Analysis of BMAA mechanisms in relation to pathogenic processes of neurodegeneration is used to critically assess the potential significance of the amino acid as well as to identify gaps in our understanding. Taken together, these two approaches provide the basis for the discussion on the potential role of BMAA as a secondary factor in neurodegenerative diseases, the rationale for further research and possible directions the research can take, which are outlined in the conclusions.

Automated summary

In this review, we have discussed the occurrence of beta-N-methylamino-L-alanine (BMAA) and its natural isomers, as well as the detection of the toxin(s) in organisms and sample types. We have also examined the general pathogenic mechanisms of neurodegenerative diseases and how BMAA fits into those mechanisms. Furthermore, we have presented the biogeography of BMAA occurrence, which can contribute to epidemiological research, and analyzed the potential significance of BMAA as well as identified gaps in our understanding. Overall, this review provides a basis for discussing the potential role of BMAA in neurodegenerative diseases, guiding further research, and outlining possible research directions.