Associations of maternal long-chain polyunsaturated fatty acids, methyl mercury, and infant development in the Seychelles Child Development Nutrition Study

Northern Ireland Centre for Food & Health (NICHE), Centre for Molecular Biosciences, University of Ulster, Coleraine BT52 1SA, Northern Ireland, United Kingdom.
NeuroToxicology (Impact Factor: 3.38). 07/2008; 29(5):776-82. DOI: 10.1016/j.neuro.2008.06.002
Source: PubMed


Fish consumption during gestation can provide the fetus with long-chain polyunsaturated fatty acids (LCPUFA) and other nutrients essential for growth and development of the brain. However, fish consumption also exposes the fetus to the neurotoxicant, methyl mercury (MeHg). We studied the association between these fetal exposures and early child development in the Seychelles Child Development Nutrition Study (SCDNS). Specifically, we examined a priori models of Omega-3 and Omega-6 LCPUFA measures in maternal serum to test the hypothesis that these LCPUFA families before or after adjusting for prenatal MeHg exposure would reveal associations with child development assessed by the BSID-II at ages 9 and 30 months. There were 229 children with complete outcome and covariate data available for analysis. At 9 months, the PDI was positively associated with total Omega-3 LCPUFA and negatively associated with the ratio of Omega-6/Omega-3 LCPUFA. These associations were stronger in models adjusted for prenatal MeHg exposure. Secondary models suggested that the MeHg effect at 9 months varied by the ratio of Omega-6/Omega-3 LCPUFA. There were no significant associations between LCPUFA measures and the PDI at 30 months. There were significant adverse associations, however, between prenatal MeHg and the 30-month PDI when the LCPUFA measures were included in the regression analysis. The BSID-II mental developmental index (MDI) was not associated with any exposure variable. These data support the potential importance to child development of prenatal availability of Omega-3 LCPUFA present in fish and of LCPUFA in the overall diet. Furthermore, they indicate that the beneficial effects of LCPUFA can obscure the determination of adverse effects of prenatal MeHg exposure in longitudinal observational studies.

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Available from: Gary J Myers
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    • "Although meant to protect children of fish consuming populations, mothers that take this advice to the extreme of avoiding seafood altogether could actually harm their own health and diminish child neurodevelopmental outcomes [9] [10] [23]. Seafood is an important source of polyunsaturated fatty acids, which are essential for the neurodevelopment of a growing fetus [8] [9] [24]. Additional risks that have been linked to decreased fish consumption and corresponding low omega-3 fatty acid levels are preeclampsia and premature delivery [9] [25]. "
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    ABSTRACT: Seafood is an important source of nutrients for fetal neurodevelopment. Most individuals are exposed to the toxic element mercury through seafood. Due to the neurotoxic effects of mercury, United States government agencies recommend no more than 340g (12oz) per week of seafood consumption during pregnancy. However, recent studies have shown that selenium, also abundant in seafood, can have protective effects against mercury toxicity. In this study, we analyzed mercury and selenium levels and selenoprotein mRNA, protein, and activity in placenta of a cohort of women in Hawaii in relation to maternal seafood consumption assessed with dietary surveys. Fish consumption resulted in differences in mercury levels in placenta and cord blood. When taken as a group, those who consumed no fish exhibited the lowest mercury levels in placenta and cord blood. However, there were numerous individuals who either had higher mercury with no fish consumption or lower mercury with high fish consumption, indicating a lack of correlation. Placental expression of selenoprotein mRNAs, proteins and enzyme activity was not statistically different in any region among the different dietary groups. While the absence of seafood consumption correlates with lower average placental and cord blood mercury levels, no strong correlations were seen between seafood consumption or its absence and the levels of either selenoproteins or selenoenzyme activity. Copyright © 2015 Elsevier GmbH. All rights reserved.
    Full-text · Article · Apr 2015 · Journal of Trace Elements in Medicine and Biology
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    • "e l s e v i e r. c o m / l o c a t e / c h e m o s p h e r e 2000; Myers et al., 2003; Davidson et al., 2006). One of the primary explanations of these inconsistencies is the compensatory effect of nutrients in seafood that overcome the neurotoxicity of MeHg (Sakamoto et al., 2004; Strain et al., 2008; Stokes-Riner et al., 2011). "
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    ABSTRACT: Methylmercury (MeHg) is a neurotoxicant and may have an adverse impact on child behavior. However, this impact was found to be inconsistent in fish-eating populations. Although the positive effects of the nutrients provided by a fish diet may overcome the effect of MeHg, the possibility of genetic variants influencing an individual's response to MeHg has also been discussed. The role of the Apolipoprotein E (APOE) epsilon 4 allele (ε4) on MeHg related neurotoxicity is still unclear. In the present study, we investigated the role of APOE variants in the relationship between cord blood mercury (Hg) and child behavior. A total of 166 subjects were recruited at delivery, and their cord blood was collected for laboratory analyses of Hg and the APOE genotype. The Child Behavior Checklist (CBCL) was administered to the subjects when they reached the age of two years. An increase in cord blood Hg concentrations in APOE ε4 carriers was consistently associated with an increased score for all CBCL syndromes. After controlling for potential confounding factors, the group of ε4 carriers with an elevated cord blood Hg concentration had significantly higher scores in the syndrome categories of general internalizing, emotionally reactive, and anxiety/depression as well as CBCL total scores. Furthermore, general externalizing and aggressive syndromes were borderline significantly higher in this group. In conclusion, we suggest that APOE may modify the toxicity of MeHg. APOE ε4 carriers may be more vulnerable to the effects of MeHg on child behavior at the age of two years.
    Full-text · Article · Jul 2014 · Chemosphere
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    • "We did not investigate the levels of lead, arsenic, cadmium, and polychlorinated biphenyls that may have adverse effects on neurodevelopment (Wasserman et al., 2004; Tang et al., 2008; Plusquellec et al., 2010; Kippler et al., 2012). The nutritional status of children may affect the developing brain (Strain et al., 2008; Wehby and Murray, 2008; Cusick and Georgieff, 2012). However, malnourished children were not observed in this study, thus the influence of nutritional status was unable to be assessed . "
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    ABSTRACT: This study attempts to elucidate the relationship between neurological effects and mercury/methylmercury concentrations in various biomarkers, including meconium, hair, fingernail, and toenail. Eight-three mother-infant pairs were recruited between August 2008 and December 2009, and follow-up examinations on these children were completed after three years. The Bayley Scales of Infant and Toddler Development (Bayley-III) for evaluating the cognitive, language, and motor development of three-year-old children were calculated and validated. The geometric mean of the total mercury concentration in meconium was 89.6ngg(-1). The methylmercury concentrations in hair, fingernail, and toenail samples were 1.96, 0.64, and 0.55μgg(-1), respectively. Seventy percent of children had hair methylmercury concentrations exceeding the U.S. environmental protection agency (EPA) reference of 1μgg(-1). A significantly positive correlation was obtained between methylmercury levels in hair, fingernail, and toenail. These methylmercury levels were also significantly positively correlated with the children's fish intake and negatively correlated with a Bayley-III scale score of expressive language. The prenatal mercury exposure, however, did not show significant influence on neurological development. High fish consumption appears to be a critical risk factor for methylmercury levels in children and may cause a lower expressive language score.
    Full-text · Article · Jan 2014 · Chemosphere
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