TY - JOUR
T1 - Waterborne manganese exposure alters plasma, brain, and liver metabolites accompanied by changes in stereotypic behaviors
AU - Fordahl, Steve
AU - Cooney, Paula
AU - Qiu, Yunping
AU - Xie, Guoxiang
AU - Jia, Wei
AU - Erikson, Keith M.
N1 - Funding Information:
This research was supported by the National Institutes of Health R15 NS061309-01 (KME).
PY - 2012/1
Y1 - 2012/1
N2 - Overexposure to waterborne manganese (Mn) is linked with cognitive impairment in children and neurochemical abnormalities in other experimental models. In order to characterize the threshold between Mn-exposure and altered neurochemistry, it is important to identify biomarkers that positively correspond with brain Mn-accumulation. The objective of this study was to identify Mn-induced alterations in plasma, liver, and brain metabolites using liquid/gas chromatography-time of flight-mass spectrometry metabolomic analyses; and to monitor corresponding Mn-induced behavior changes. Weanling Sprague-Dawley rats had access to deionized drinking water either Mn-free or containing 1. g Mn/L for 6. weeks. Behaviors were monitored during the sixth week for a continuous 24. h period while in a home cage environment using video surveillance. Mn-exposure significantly increased liver, plasma, and brain Mn concentrations compared to control, specifically targeting the globus pallidus (GP). Mn significantly altered 98 metabolites in the brain, liver, and plasma; notably shifting cholesterol and fatty acid metabolism in the brain (increased oleic and palmitic acid; 12.57 and 15.48 fold change (FC), respectively), and liver (increased oleic acid, 14.51 FC; decreased hydroxybutyric acid, - 14.29 FC). Additionally, Mn-altered plasma metabolites homogentisic acid, chenodeoxycholic acid, and aspartic acid correlated significantly with GP and striatal Mn. Total distance traveled was significantly increased and positively correlated with Mn-exposure, while nocturnal stereotypic and exploratory behaviors were reduced with Mn-exposure and performed largely during the light cycle compared to unexposed rats. These data provide putative biomarkers for Mn-neurotoxicity and suggest that Mn disrupts the circadian cycle in rats.
AB - Overexposure to waterborne manganese (Mn) is linked with cognitive impairment in children and neurochemical abnormalities in other experimental models. In order to characterize the threshold between Mn-exposure and altered neurochemistry, it is important to identify biomarkers that positively correspond with brain Mn-accumulation. The objective of this study was to identify Mn-induced alterations in plasma, liver, and brain metabolites using liquid/gas chromatography-time of flight-mass spectrometry metabolomic analyses; and to monitor corresponding Mn-induced behavior changes. Weanling Sprague-Dawley rats had access to deionized drinking water either Mn-free or containing 1. g Mn/L for 6. weeks. Behaviors were monitored during the sixth week for a continuous 24. h period while in a home cage environment using video surveillance. Mn-exposure significantly increased liver, plasma, and brain Mn concentrations compared to control, specifically targeting the globus pallidus (GP). Mn significantly altered 98 metabolites in the brain, liver, and plasma; notably shifting cholesterol and fatty acid metabolism in the brain (increased oleic and palmitic acid; 12.57 and 15.48 fold change (FC), respectively), and liver (increased oleic acid, 14.51 FC; decreased hydroxybutyric acid, - 14.29 FC). Additionally, Mn-altered plasma metabolites homogentisic acid, chenodeoxycholic acid, and aspartic acid correlated significantly with GP and striatal Mn. Total distance traveled was significantly increased and positively correlated with Mn-exposure, while nocturnal stereotypic and exploratory behaviors were reduced with Mn-exposure and performed largely during the light cycle compared to unexposed rats. These data provide putative biomarkers for Mn-neurotoxicity and suggest that Mn disrupts the circadian cycle in rats.
KW - Behavior
KW - Biomarker
KW - Circadian rhythm
KW - Manganese
KW - Metabolomics
KW - Neurotoxicity
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U2 - 10.1016/j.ntt.2011.10.003
DO - 10.1016/j.ntt.2011.10.003
M3 - Article
C2 - 22056924
AN - SCOPUS:82655169242
SN - 0892-0362
VL - 34
SP - 27
EP - 36
JO - Neurotoxicology and Teratology
JF - Neurotoxicology and Teratology
IS - 1
ER -