Aflatoxin exposure is inversely associated with IGF1 and IGFBP3 levels in vitro and in Kenyan schoolchildren. Issue 3 (25th January 2014)

• Record Type: Journal Article
• Authors: Castelino, Jovita M.; Routledge, Michael N.; Wilson, Shona; Dunne, David W.; Mwatha, Joseph K.; Gachuhi, Kimani; Wild, Christopher P.; Gong, Yun Y.
• Is Part Of: Molecular nutrition & food research. Volume 59:Issue 3(2015:Mar.)
• Page Start: 574
• Page End: 581
• Publication Date: 2014-01-25
• Subjects: Food -- Biotechnology -- Periodicals; Food -- Microbiology -- Periodicals; Nutrition -- Periodicals; Food -- Toxicology -- Periodicals; Nutrition -- Periodicals; Food Microbiology -- Periodicals; Food Technology -- Periodicals; Molecular Biology -- Periodicals; 664.0705
• DOI: 10.1002/mnfr.201300619
• Languages: English
• ISSNs: 1613-4125

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="mnfr2159-sec-0010" sec-type="section"> <title>Scope</title> <p>This study explores the relationship between aflatoxin and the insulin‐like growth factor (IGF) axis and its potential effect on child growth.</p> </sec> <sec id="mnfr2159-sec-0020" sec-type="section"> <title>Methods and results</title> <p>One hundred and ninety‐nine Kenyan schoolchildren were studied for aflatoxin‐albumin adduct (AF‐alb), IGF1 and IGF‐binding protein‐3 (IGFBP3) levels using ELISA. AF‐alb was inversely associated with IGF1 and IGFBP3 (<italic>p</italic> < 0.05). Both IGF1 and IGFBP3 were significantly associated with child height and weight (<italic>p</italic> < 0.01). Children in the highest tertile of AF‐alb exposure (>198.5 pg/mg) were shorter than children in the lowest tertile (<74.5 pg/mg), after adjusting for confounders (<italic>p</italic> = 0.043). Path analysis suggested that IGF1 levels explained ∼16% of the impact of aflatoxin exposure on child height (<italic>p</italic> = 0.052). To further investigate this putative mechanistic pathway, HHL‐16 liver cells (where HHL‐16 is human hepatocyte line 16 cells) were treated with aflatoxin B<sub>1</sub> (0.5, 5 and 20 μg/mL for 24–48 h). IGF1 and IGFBP3 gene expression measured by quantitative PCR and protein in culture media showed a significant down‐regulation of IGF genes and reduced IGF protein levels.</p> </sec> <sec id="mnfr2159-sec-0030" sec-type="section"> <title>Conclusion</title> <p>Aflatoxin treatment resulted in a significant decrease in IGF gene and protein expression in vitro. IGF protein levels were also lower in children with the highest levels of AFB‐alb adducts. The data suggest that aflatoxin‐induced changes in IGF protein levels could contribute to growth impairment where aflatoxin exposure is high.</p> </sec> </abstract>