Cox PA, Banack SA, Murch SJ.
Biomagnification of cyanobacterial neurotoxins and neurodegenerative disease among the Chamorro people of Guam.
Proc Natl Acad Sci U S A. 2003 Nov 11;100(23):13380-3.
PubMed.
This work is interesting, but highly speculative since the linkage between BMAA or other cycad components or cycads themselves remains tenuous, and earlier data over a decade ago to suggest that cycads or BMAA induced a progressive neurological disease in animals remain to be replicated and explained. Further, while I am only an infrequent traveler to Guam, having lived there in the early 1950s for a year, and with two more recent visits within the past five years, my understanding is that flying foxes are no longer extant on Guam and have not been for some time, due to over-hunting or to the fact that after the introduction of snakes on Guam, birds have disappeared because snakes have thrived without natural predators and have eaten the eggs of bird life. This might also apply to flying fox life. Thus, where does that leave us with the role of BMAA and cycads in Guam ALS/PDC and the findings in this paper? I think the honest answer is we still do not know, and while this paper presents interesting data, it will take animal model studies of the effects of BMAA and cycads to determine if they really can produce a progressive neurological disease like Guam ALS/PDC in animals, as well as more documentation that BMAA or other cycad constituents are present in the brains of people with neurodegenerative diseases.
Comments
University of Pennsylvania
This work is interesting, but highly speculative since the linkage between BMAA or other cycad components or cycads themselves remains tenuous, and earlier data over a decade ago to suggest that cycads or BMAA induced a progressive neurological disease in animals remain to be replicated and explained. Further, while I am only an infrequent traveler to Guam, having lived there in the early 1950s for a year, and with two more recent visits within the past five years, my understanding is that flying foxes are no longer extant on Guam and have not been for some time, due to over-hunting or to the fact that after the introduction of snakes on Guam, birds have disappeared because snakes have thrived without natural predators and have eaten the eggs of bird life. This might also apply to flying fox life. Thus, where does that leave us with the role of BMAA and cycads in Guam ALS/PDC and the findings in this paper? I think the honest answer is we still do not know, and while this paper presents interesting data, it will take animal model studies of the effects of BMAA and cycads to determine if they really can produce a progressive neurological disease like Guam ALS/PDC in animals, as well as more documentation that BMAA or other cycad constituents are present in the brains of people with neurodegenerative diseases.
View all comments by John Trojanowski