Format

Send to

Choose Destination
Toxicon. 2016 Jan;109:7-12. doi: 10.1016/j.toxicon.2015.11.003. Epub 2015 Nov 10.

The use of L-serine to prevent β-methylamino-L-alanine (BMAA)-induced proteotoxic stress in vitro.

Author information

1
The Cell Biology Group, University of Technology Sydney, Broadway, NSW, 2007, Australia.
2
The Cell Biology Group, University of Technology Sydney, Broadway, NSW, 2007, Australia. Electronic address: Kenneth.Rodgers@uts.edu.au.

Abstract

β-methylamino-L-alanine (BMAA), a non-protein amino acid synthesised by cyanobacteria, has been linked to a complex neurological disorder on Guam and more recently to other cases of sporadic ALS (sALS), however the mechanisms of BMAA toxicity are not completely understood. We have previously demonstrated that BMAA is misincorporated into newly synthesised proteins by human neuroblastoma cells and fibroblasts, resulting in the formation of autofluorescent material and the induction of apoptotic cell death. In the present study we show that BMAA at low levels does not cause an acute toxicity in neuroblastoma cells but increases the expression of the ER stress marker, C/EBP homologous protein (CHOP) and increases the activity of the pro-apoptotic enzyme caspase-3. We also observed an increase in the activity of the lysosomal cysteine proteases cathepsin B and L, characteristic of the accumulation of proteins in the lysosomal system. We were able to prevent these proteotoxic effects in neuroblastoma cells through co-treatment with l-serine suggesting that they resulted from incorporation of BMAA into proteins. Misincorporation provides a possible mechanism whereby BMAA could initiate misfolding, and the accumulation of aggregate-prone proteins in neurons. This build-up of misfolded proteins could explain the long latency period of the disease previously reported on Guam.

KEYWORDS:

ALS; BMAA; MND; Non-protein amino acids; Protein aggregation; Unfolded protein response

PMID:
26559613
DOI:
10.1016/j.toxicon.2015.11.003
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center