Room: AAPM ePoster Library
Purpose: Lead (Pb) is a well-known neurotoxicant and environmental hazard. Recent epidemiologic evidence has linked Pb exposure with neurological deterioration leading to neurodegenerative diseases such as AD.
Methods: To understand brain regional distribution of Pb and its interaction with other metal ions, we used synchrotron micro-x-ray fluorescence (?-XRF) to map the metal distribution pattern and to quantify concentrations metals in brains. Pb-exposed mice received oral gavage of 27 mg Pb/kg as Pb acetate (PbAc) once daily for 4 weeks; the control mice received NaAc. Brain tissues were cut into slices and subjected for analysis. Synchrotron ?-XRF scans were run on the P06 beamline at the Deutsches Elektronen-Synchrotron (DESY) facility. Coarse scans of the entire brain were run to locate the cortex and hippocampus regions, after which scans with smaller step sizes of about 1 ?m were run in these areas.
Results: The results show that: a) Pb deposits in localized spots of 1-3 ?m in the cortex region of both the exposed and unexposed samples, with over 10 times more spots in exposed samples than that in unexposed samples; b) selenium (Se) co-deposits with Pb and is strongly correlated with Pb in these spots; c) the total Pb signals in brain slices in an exposed mouse are much larger than those in a control mouse. There is also evidence of strong correlation of Pb and Se as well as other metals in other regions.
Conclusion: These results suggest that Se may play a crucial role in Pb-induced neurotoxicity. Future studies will be conducted to investigate the relationship between Pb exposure and ensuring Se detoxification responses, and the implication in the etiology of AD.
Not Applicable / None Entered.
Not Applicable / None Entered.