title: Differential toxicity of novel aluminium compounds in hippocampal culture.
abstract: The dependence of aluminium (Al) toxicity on its chemical form has been implicated in previous studies, but the complex chemistry of Al in solutions of biological preparations has hampered a reliable assessment. Here, we assessed the toxicity of select and pure Al(III) citrate compounds, well-characterized at physiological pH, and compared it with Al from standard solution (in HCl). Cell death rates of neurones and glia were established in hippocampal cultures following 3h incubations in a HEPES-buffered solution and 24h incubations in full culture medium. Overall, Al toxicity was found to vary considerably between compounds, with duration of exposure, medium type, and cell type as factors. While Al (from atomic absorption standard solution) induced the highest levels of cell death, AlCit1, ((NH(4))(5)[Al(C(6)H(4)O(7))(2)].2H(2)O) was the most toxic citrate compound, and affected viability of neurones more than glia (viability at 500 microM/3h-neurones: 40%; glia: 60%). AlCit2 (K(4)[Al(C(6)H(4)O(7))(C(6)H(5)O(7))].4H(2)O) did not show any toxicity after 3h, but severe toxicity after 24h in both cell types (viability at 500 microM/24h-neurones: 50%, glia: 30%). AlCit3 ((NH(4))(5)[Al(3)(C(6)H(4)O(7))(3)(OH)(H(2)O)].(NO(3)).6H(2)O), exhibited a cell type specific toxicity profile, and only affected neuronal viability at both time points (neuronal viability at 500 microM/3h: 20%). The medium type and presence of serum (FBS) was also found to contribute to the toxicity pattern, with serum providing partial protection. Since the Al(III) compounds introduced here are assumed to form in vivo, our data raise further awareness for the toxicity of Al(III) in general, and for the importance of Al speciation and cell type specific actions in its toxicity.
authors.affiliation: School of Medical Sciences, College of Life Sciences and Medicine, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, Scotland, UK. b.platt@abdn.ac.uk
authors.forename: Bettina
authors.initials: B
authors.lastname: Platt
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Drysdale
authors.forename: Christiane
authors.initials: C
authors.lastname: Nday
authors.forename: Eva von Linstow
authors.initials: Ev
authors.lastname: Roloff
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Drever
authors.forename: Athanasios
authors.initials: A
authors.lastname: Salifoglou
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media; D016895:Culture Media, Serum-Free; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D009457:Neuroglia / Q000187:drug effects / Q000473:pathology; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D009942:Organometallic Compounds / Q000737:chemistry / Q000633:toxicity; D051381:Rats; D013054:Spectrophotometry, Atomic; D013329:Structure-Activity Relationship; D014961:X-Ray Diffraction
chemical_list: D017607:Aluminum Compounds; D003470:Culture Media; D016895:Culture Media, Serum-Free; D009942:Organometallic Compounds