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

https://doi.org/10.1194/jlr.M033068Get rights and content
Under a Creative Commons license
open access

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.

isoprostane
isofuran
C-reactive protein
mercury
selenium

Cited by (0)

Funding for this work was provided by Government of Canada Federal Program for International Polar Year, Canadian Institutes of Health Research, Health Canada, Aboriginal Affairs and Northern Development Canada, Government of Nunavut, University of Toronto, and Arctic Net. The authors have no conflicts of interest to disclose.

Abbreviations:

    BMI

    body mass index

    CINE

    Centre for Indigenous Peoples’ Nutrition and Environment

    CI

    confidence interval

    CRP

    C-reactive protein

    CVD

    cardiovascular disease

    GC-NICI-MS

    gas chromatography-negative ion chemical ionization-mass spectrometry

    GSH

    glutathione

    HDL-C

    high density lipoprotein cholesterol

    IPY

    International Polar Year

    IsoF

    isofuran

    IsoP

    isoprostane

    LDL-C

    low density lipoprotein cholesterol

    MeHg

    methylmercury

    SBP

    systolic blood pressure

    WC

    waist circumference