Occurrence of β‐methylamino‐l‐alanine (BMAA) in ALS/PDC patients from Guam

  title={Occurrence of $\beta$‐methylamino‐l‐alanine (BMAA) in ALS/PDC patients from Guam},
  author={S J Murch and Paul Alan Cox and Sandra Anne Banack and John C.H. Steele and Oliver W. Sacks},
  journal={Acta Neurologica Scandinavica},
We tested the brain tissues of the Chamorro people of Guam who died of amyotrophic lateral sclerosis/Parkinsonism dimentia complex (ALS/PDC) for the neurotoxin β‐methylamino‐l‐alanine (BMAA). We used validated high‐pressure liquid chromatography and liquid chromatography‐mass spectrometry analyses to test well‐characterized archival tissues of the superior frontal gyrus from eight Chamorros from Guam and a comparison group of 15 Canadians. BMAA was found as a free amino acid in 83% of Chamorro… 

β-N-methylamino-l-alanine analysis in the brains of patients with Kii ALS/PDC

The Kii Peninsula of Japan and the island of Guam are known as high-incidence areas of amyotrophic lateral sclerosis and parkinsonism–dementia complex, and exposure to β-N-methylamino-l-alanine (BMAA), a neurotoxin produced by cyanobacteria, has been proposed as a risk factor for ALS/PDC in Guam.

Multiple neurotoxic items in the Chamorro diet link BMAA with ALS/PDC

  • S. BanackS. Murch
  • Medicine, Biology
    Amyotrophic lateral sclerosis : official publication of the World Federation of Neurology Research Group on Motor Neuron Diseases
  • 2009
It is suggested that the Chamorro people are exposed to chronically low levels of BMAA in the diet and that further research is needed to understand chronic BMAA toxicity.

Cyanobacterial neurotoxin BMAA in ALS and Alzheimer’s disease

Objective –  The aim of this study was to screen for and quantify the neurotoxic amino acid β‐N‐methylamino‐l‐alanine (BMAA) in a cohort of autopsy specimens taken from Alzheimer’s disease (AD),

β-methylamino-L-alanine (BMAA) is not found in the brains of patients with confirmed Alzheimer’s disease

Following the full validation of a highly accurate and sensitive mass spectrometric method, no trace of BMAA was detected in the diseased brain or in the control specimens, calling into question the significance of this compound in neurodegenerative disease.

Linking β-methylamino-L-alanine exposure to sporadic amyotrophic lateral sclerosis in Annapolis, MD.

β-N-Methylamino-L-alanine Induces Neurological Deficits and Shortened Life Span in Drosophila

It is found that dietary intake of BMAA reduced life span, locomotor functions, and learning and memory abilities in flies, and that Drosophila serves as a useful model in dissecting the pathogenesis of ALS/PDC.

Retention of the cyanobacterial neurotoxin β‐N‐methylamino‐l‐alanine in melanin and neuromelanin‐containing cells – a possible link between Parkinson‐dementia complex and pigmentary retinopathy

Investigation of the distribution of 3H‐BMAA in mice and frogs found a distinct retention in melanin‐ containing tissues such as the eye and neuromelanin‐containing neurons in frog brain, and interaction of BMAA with melanin may be a possible link between PDC and pigmentary retinopathy.



Distribution of the neurotoxic nonprotein amino acid BMAA in Cycas micronesica

Cycad neurotoxins are concentrated in cycad reproductive organs, with the highest concentrations being found in the immature staminate sporangium and the outmost layer of the sarcotesta, consistent with the putative evolutionary role of BMAA as an antiherbivory compound, as well as the biomagnification of the compound in flying foxes that ingest the seed sarcOTesta.

Biomagnification of cyanobacterial neurotoxins and neurodegenerative disease among the Chamorro people of Guam

  • P. CoxS. BanackS. Murch
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2003
The biomagnification of BMAA through the Guam ecosystem fits a classic triangle of increasing concentrations of toxic compounds up the food chain, which may explain why the incidence of ALS-PDC among the Chamorro was 50-100 times the occurrence of amyotrophic lateral sclerosis elsewhere.

Guam amyotrophic lateral sclerosis-parkinsonism-dementia linked to a plant excitant neurotoxin.

The hypothesis that cycad exposure plays an important role in the etiology of the Guam disease is supported, as existing epidemiological and animal data support the hypothesis.

Familial nature and continuing morbidity of the amyotrophic lateral sclerosis-parkinsonism dementia complex of Guam

Data indicate that tangles, as well as plaques, generate inflammatory reactions and that such reactions may exacerbate the fundamental pathology in bodig as wellAs in AD.

Cycad neurotoxins, consumption of flying foxes, and ALS-PDC disease in Guam.

The Chamorro people of Guam have been afflicted with a complex of neurodegenerative diseases with similarities to ALS, AD, and PD at a far higher rate than other populations throughout the world.

Biomagnification of cycad neurotoxins in flying foxes

β-Methylamino-l-alanine (BMAA) occurs in higher levels in museum specimens of the Guamanian flying fox than in the cycad seeds the flying foxes feed on, confirming the hypothesis that cycad