title: β-N-methylamino-L-alanine (BMAA) uptake by the animal model, Daphnia magna and subsequent oxidative stress.
abstract: β-N-methylamino-l-alanine (BMAA), produced by cyanobacteria, is a neurotoxin implicated in Amyotrophic lateral sclerosis/Parkinsonism dementia complex (ALS/PDC). BMAA concentrations in cyanobacteria are lower than those thought to be necessary to result in neurological damage thus bioaccumulation or biomagnification is required to achieve concentrations able to cause neurodegeneration. Many cyanobacteria produce BMAA and uptake routes into the food web require examination. In this study we investigate the uptake of BMAA by adult phytoplanktivorus Daphnia magna via exposure to dissolved pure BMAA and BMAA containing cyanobacteria, as well as the subsequent oxidative stress response in the daphnia. Free BMAA and protein-associated BMAA were quantified by LC-MS/MS. Dissolved BMAA was taken up and was found as free BMAA in D. magna. No protein-associated BMAA was detected in D. magna after a 24-h exposure period. No BMAA was detectable in D. magna after exposure to BMAA containing cyanobacteria. BMAA inhibited the oxidative stress defence and biotransformation enzymes within 24-h exposure in the tested Daphnia and could therefore impair the oxidant status and the capability of detoxifying other substances in D. magna.
authors.affiliation: Department of Biochemistry and Microbiology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa. Electronic address: esterhuizen-londt@tu-berlin.de.
authors.forename: Maranda
authors.initials: M
authors.lastname: Esterhuizen-Londt
authors.affiliation: Ecophysiology and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 301, 12587 Berlin, Germany. Electronic address: wiegand@biology.sdu.dk.
authors.forename: Claudia
authors.initials: C
authors.lastname: Wiegand
authors.affiliation: Department of Biochemistry and Microbiology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa. Electronic address: tim.downing@nmmu.ac.za.
authors.forename: Tim G
authors.initials: TG
authors.lastname: Downing
mesh_terms: D000599:Amino Acids, Diamino / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001427:Bacterial Toxins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001711:Biotransformation; D002853:Chromatography, Liquid; D000458:Cyanobacteria; D000087522:Cyanobacteria Toxins; D003621:Daphnia / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D004784:Environmental Monitoring; D008387:Marine Toxins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D052998:Microcystins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D009498:Neurotoxins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D053719:Tandem Mass Spectrometry
chemical_list: D000599:Amino Acids, Diamino; D000975:Antioxidants; D001427:Bacterial Toxins; D000087522:Cyanobacteria Toxins; D008387:Marine Toxins; D052998:Microcystins; D009498:Neurotoxins; C001824:beta-N-methylamino-L-alanine
keywords: Ecotoxicology; Oxidative stress; Uptake; β-N-Methylamino-l-alanine