Aflatoxin exposure is inversely associated with IGF1 and IGFBP3 levels in vitro and in Kenyan schoolchildren

Mol Nutr Food Res. 2015 Mar;59(3):574-81. doi: 10.1002/mnfr.201300619. Epub 2014 Jan 25.


Scope: This study explores the relationship between aflatoxin and the insulin-like growth factor (IGF) axis and its potential effect on child growth.

Methods and results: 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 (p < 0.05). Both IGF1 and IGFBP3 were significantly associated with child height and weight (p < 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 (p = 0.043). Path analysis suggested that IGF1 levels explained ∼16% of the impact of aflatoxin exposure on child height (p = 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 B1 (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.

Conclusion: 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.

Keywords: Aflatoxins; Child growth; Exposure biomarker; IGFBP3; Insulin-like growth factor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Aflatoxin B1 / toxicity
  • Aflatoxins / blood
  • Aflatoxins / toxicity*
  • Albumins
  • Body Height / drug effects
  • Body Weight / drug effects
  • Cell Line / drug effects
  • Child
  • Cross-Sectional Studies
  • Female
  • Food Contamination / analysis
  • Hepatocytes / drug effects
  • Humans
  • Insulin-Like Growth Factor Binding Protein 3 / blood*
  • Insulin-Like Growth Factor Binding Protein 3 / genetics
  • Insulin-Like Growth Factor I / analysis*
  • Insulin-Like Growth Factor I / genetics
  • Kenya
  • Male


  • Aflatoxins
  • Albumins
  • IGF1 protein, human
  • IGFBP3 protein, human
  • Insulin-Like Growth Factor Binding Protein 3
  • aflatoxin-albumin adduct
  • Insulin-Like Growth Factor I
  • Aflatoxin B1