Abstract
Reports that iron, zinc and copper homeostasis are in aberrant homeostasis are common for various neurodegenerative diseases, particularly for Huntington’s disease, Parkinson’s disease, and Alzheimer’s disease. Manipulating the levels of these elements in the brain through the application of chelators has been and continues to be tested therapeutically in clinical trials with mixed results. Much of the data indicating that these metals are abnormally concentrated in Alzheimer’s disease and Parkinson’s disease brain tissue was generated through the analysis of post-mortem human tissue which was archived in formalin. In this study, we evaluated the effect of formalin fixation of brain on the levels of three important transition metals (iron, copper, and zinc) by atomic absorption spectroscopy. Paired brain specimens were obtained at autopsy for each case; one was conserved by formalin archival (averaging four years), the other was rapidly frozen. Both white and grey matter samples were analyzed and the concentrations of iron and zinc were found to decrease with fixation. Iron was reduced by 40% (P < 0.01), and zinc by 77% (P < 0.0001); copper concentrations increased by 37% (P < 0.05) by the paired T-test. The increase in copper is likely due to contamination from trace copper in the formalin. These results indicate that transition metal data obtained from fixed tissue may be heavily distorted and care should be taken in interpreting this data.
References
Andrasi E, Nadasdi J, Molznar Z, Bezur L et al (1990) Determination of main and trace element contents of human brain by NAA and ICP-AES methods. Biol Trace Elem Res 26(7):691–698
Braak H, Braak E (1991) Neuropathological stageing of Alzheimer-related changes. Acta Neuropathol 82:239–259
Bush V, Moyer T, Batts K, Parisi J (1995) Essential and toxic element concentrations in fresh and formalin-fixed human autopsy tissues. Clin Chem 41(2):284–294
Cornett C, Markesbery W, Ehmann W (1998) Imbalances of trace elements related to oxidative damage in AD brain. Neurotoxicology 19:339–345
Crapper McLaughlan D, Dalton A, Kruck T, Bell M et al (1991) Intramusclar desferrioxamine in patients with Alzheimer’s disease. Lancet 337:1304–1308
Deibel M, Ehmann W, Markesbery W (1996) Copper, iron and zinc imbalances in severely degenerated brain regions in Alzheimer’s disease: possible relation to oxidative stress. J Neurol Sci 143:137–142
Gellein K, Flaten T, Erikson K, Aschner M, Syverson T (2008) Leaching of trace elements from biological tissue by formalyn. Biol Trace Elem Res 121:221–225
Goodman L (1953) Alzheimer’s disease; a clinico-pathologic analysis of 23 cases with a theory on pathogenesis. J Nerv Ment Dis 118:97–130
Hallgren B, Sourander P (1958) The effect of age on the non-haemin iron in the human brain. J Neurochem 3:41–51
Hallgren B, Sourander P (1960) The non-haemin iron in the cerebral cortex in Alzheimer’s disease. J Neurochem 5:307–310
Lannfelt L, Blennow K, Zetterberg H, Batsman S et al (2008) Safety, efficacy and biomarker findings of PBT2 in targeting Abeta as a modifying therapy for Alzheimer’s disease; a phase IIa, double blind randomized placebo controlled trial. Lancet Neurol 7:779–786
Loeffler D, LeWitt P, Juneau P, Sima A et al (1996) Increased regional brain concentrations of ceruloplasmin in neurodegenerative disorders. Brain Res 738:265–274
Lovell M, Robertson J, Teesdale W, Campbell J, Markesbery W (1998) Copper, iron and zinc in AD senile plaques. J Neurol Sci 158:47–52
Nunomura A, Perry G, Aliev G, Hirei K et al (2001) Oxidative damage is the earliest eventin Alzheimer Disease. J Neuropathol Exp Neurol 60:759–767
Rottkamp C, Raina A, Zhu X, Gaier E et al (2001) Redox-active iron mediates amyloid-beta toxicity. Free Radic Biol Med 30:447–450
Rulon L, Robertson J, Lovell M, Deibel M et al (2000) Serum zinc levels and Alzheimer’s disease. Biol Trace Elem Res 75:79–85
Samudralwar D, Diprete C, Ni B, Ehmann W, Markesbery W (1995) Elemental imbalances in the olfactory pathway in Alzheimer’s disease. J Neurol Sci 130:139–145
Squitti R, Rossini P, Cassetta E, Moffa F et al (2002) D-penicillamine reduces serum oxidatitive stress in AD patients. Eur J Clin Inv 32:51–59
Thompson C, Markesbery W, Ehmann W, Mao Y, Vance D (1988) Regional brain trace-element studies in Alzheimer’s disease. Neurotoxicology 9:1–8
Acknowlegements
This research was funded by the National Institutes of Health (AG20948). Harry V. Vinters is supported in part by P01 AG12435, P50 AG16570 and the Daljit S. and Elaine Sarkaria Chair in Diagnostic Medicine. None of the authors have real or potential conflicts of interest related to this work.
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Schrag, M., Dickson, A., Jiffry, A. et al. The effect of formalin fixation on the levels of brain transition metals in archived samples. Biometals 23, 1123–1127 (2010). https://doi.org/10.1007/s10534-010-9359-4
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DOI: https://doi.org/10.1007/s10534-010-9359-4