New insights regarding tissue Se and Hg interactions on oxidative stress from plasma IsoP and IsoF measures in the Canadian Inuit population

• Published in: Journal of Lipid Research
• Main Authors: Dalal Alkazemi, Grace M. Egeland, L. Jackson Roberts, II, Hing M. Chan, Stan Kubow
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2013
• Subjects: isoprostane; isofuran; C-reactive protein; mercury; selenium; Biochemistry; QD415-436; Arctic; inuit
• Online Access: https://doi.org/10.1194/jlr.M033068; https://doaj.org/article/fd449cd314c340a084307ab7a21b5eb5

Despite animal and in vitro studies demonstrating pro-oxidative effects of Hg, previous human work showed no relationship between tissue Hg and plasma levels of F2-isoprostanes (IsoPs), a whole-body oxidative stress marker. We hypothesized that another IsoP species, isofurans (IsoFs), was a more sensitive indicator of Hg-mediated oxidative stress, which can be modified by tissue Se status. A cross-sectional study was carried out involving individuals from a random subset (n = 233) of Inuit adults from a population-based survey (n = 2,595) of 36 Canadian Arctic Inuit communities to assess the relationships of plasma IsoPs to Se and Hg status indicators. F2-IsoPs were inversely correlated with blood Se (r =−0.186, P = 0.005) and toenail Se (r =−0.146, P = 0.044), but not correlated with Hg. IsoFs were inversely correlated with blood Se (r =−0.164, P = 0.014) and positively correlated with Hg (r = 0.228, P < 0.001) and Hg:Se (r = 0.340, P < 0.001). The strength of the correlations remained unchanged after multivariate adjustments. Multivariate analysis showed that F2-IsoPs were not positively associated with Hg but with Hg:Se (β= 0.148, P = 0.021). We conclude that Se and Hg status and their interactions are important factors modulating F2-IsoP and IsoF levels such that the Inuit may be protected from Hg-induced oxidative stress because of their high Se status.