title: New insights regarding tissue Se and Hg interactions on oxidative stress from plasma IsoP and IsoF measures in the Canadian Inuit population.
abstract: 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.
authors.affiliation: School of Dietetics and Human Nutrition, McGill University, Ste-Anne-de-Bellevue, QC, Canada.
authors.forename: Dalal
authors.initials: D
authors.lastname: Alkazemi
authors.forename: Grace M
authors.initials: GM
authors.lastname: Egeland
authors.forename: L Jackson
authors.initials: LJ
authors.lastname: Roberts
authors.forename: Hing M
authors.initials: HM
authors.lastname: Chan
authors.forename: Stan
authors.initials: S
authors.lastname: Kubow
mesh_terms: D000293:Adolescent; D000328:Adult; D002170:Canada; D028441:F2-Isoprostanes / Q000097:blood*; D005260:Female; D005663:Furans / Q000097:blood*; D006801:Humans; D008297:Male; D008628:Mercury / Q000097:blood / Q000737:chemistry*; D015999:Multivariate Analysis; D018384:Oxidative Stress; D012643:Selenium / Q000097:blood / Q000737:chemistry*; D055815:Young Adult
chemical_list: D028441:F2-Isoprostanes; D005663:Furans; D008628:Mercury; D012643:Selenium
keywords: C-reactive protein; isofuran; isoprostane; mercury; selenium