Selenium from dietary sources and motor functions in the Brazilian Amazon

• DOI: 10.1016/j.neuro.2011.04.005
• Publication Date: 2011-05-07T21:24:54Z
• Authors: Mélanie Lemire; Myriam Fillion; Benoît Frenette; Carlos José Sousa...; Jean Rémy Davée G...; Fernando Barbosa; Donna Mergler
• Keywords: Adult; Male; Motor functions; Adolescent; Neuroscience(all); Food Contamination; Toxicology; 01 natural sciences; Mass Spectrometry; Selenium; Humans; Ecosystem; Aged; 0105 earth and related environmental sciences; Aged, 80 and over; 2. Zero hunger; Analysis of Variance; Chi-Square Distribution; Brain; Mercury; Brazilian Amazon; 6. Clean water; Diet; 3. Good health; Cross-Sectional Studies; Lead; Fish-eating population; Linear Models; Muscle; Environmental Pollutants; Female; Biomarkers; Brazil; Hair

Selenium (Se) is a well-known anti-oxidant with critical role in the proper functioning of nervous and muscle functions. Se deficiency has been associated both cognitive neuromotor impairment, while sensory motor deficits have attributed to excess Se. In Lower Tapajós Region Brazilian Amazon, riverside populations present wide range levels. These fish-eating communities among highest mercury (Hg) exposures reported world today, recently, lead (Pb) exposure identified. Some studies suggest that intake can be protective for Hg and/or Pb toxicity, however, data from animal human are inconsistent. The objective study was examine relations between biomarkers functions, taking into account co-variables Pb. Participants (n=448), aged 15-87 y, were recruited 12 along River. concentrations measured whole blood (B-Se), plasma (P-Se), hair (H-Se) urine (U-Se) by ICP-MS. Whole (B-Hg) (B-Pb) also Interview-administered questionnaires served collect information on socio-demographics medical history. All participants underwent complete visual examination performed tests functions (Branches Alternate Movement Task, Santa Ana Test, Dynamometer Grooved Pegboard Test). B-Se varied 103 1500 μg/L (median 228 μg/L), P-Se 53.6 913 135 H-Se 0.4 3.8 μg/g 0.7 μg/g) U-Se 2.3 1375 cr. 33.6 cr.). Median B-Hg B-Pb levels 42.5 113 respectively. multivariable analysis, (log-transformed) positively related better performance all tests, socio-demographic consistently showed stronger associations compared other biomarkers. Regression estimates considerably when controlling B-Hg. When stratifying at median concentrations, presented outcomes only high concentrations. This first report beneficial effects status For this population elevated exposure, dietary may brain However, these findings not necessarily applicable lower status, which case people who do rely heavily fish consumption, they Brazil, United States or elsewhere. mostly observed P-Se, suggesting selenoproteins good outcomes.