title: The cyanobacterial neurotoxin β-N-methylamino-l-alanine (BMAA) induces neuronal and behavioral changes in honeybees.
abstract: The cyanobacterially produced neurotoxin beta-N-methylamino-l-alanine (BMAA) is thought to induce amyotrophic lateral sclerosis/Parkinsonism dementia complex (ALS/PDC)-like symptoms. However, its mechanism of action and its pathway of intoxication are yet unknown. In vivo animal models suitable for investigating the neurotoxic effect of BMAA with applicability to the human are scarce. Hence, we used the honeybee (Apis mellifera) since its nervous system is relatively simple, yet having cognitive capabilities. Bees fed with BMAA-spiked sugar water had an increased mortality rate and a reduced ability to learn odors in a classical conditioning paradigm. Using (14)C-BMAA we demonstrated that BMAA is biologically available to the bee, and is found in the head, thorax and abdomen with little to no excretion. BMAA is also transferred from one bee to the next via trophallaxis resulting in an exposure of the whole beehive. BMAA bath application directly onto the brain leads to an altered Ca(2+) homeostasis and to generation of reactive oxygen species. These behavioral and physiological observations suggest that BMAA may have effects on bee brains similar to those assumed to occur in humans. Therefore the bee could serve as a surrogate model system for investigating the neurological effects of BMAA.
authors.affiliation: Human and Environmental Toxicology, University of Konstanz, Jacob-Burckhardt-Strasse 25, 78457 Konstanz, Germany. oliver.okle@uni-konstanz.de
authors.forename: Oliver
authors.initials: O
authors.lastname: Okle
authors.forename: Lisa
authors.initials: L
authors.lastname: Rath
authors.forename: C Giovanni
authors.initials: CG
authors.lastname: Galizia
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Dietrich
mesh_terms: D000599:Amino Acids, Diamino / Q000633:toxicity*; D000818:Animals; D001516:Bees / Q000187:drug effects* / Q000378:metabolism; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D003214:Conditioning, Classical / Q000187:drug effects / Q000502:physiology; D000458:Cyanobacteria; D000087522:Cyanobacteria Toxins; D007858:Learning / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D009498:Neurotoxins / Q000633:toxicity*; D011897:Random Allocation; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000599:Amino Acids, Diamino; D000087522:Cyanobacteria Toxins; D009498:Neurotoxins; D017382:Reactive Oxygen Species; C001824:beta-N-methylamino-L-alanine