Are additive effects of dietary surfactants on intestinal tight junction integrity an overlooked human health risk? - A mixture study on Caco-2 monolayers

Food Chem Toxicol. 2017 Aug;106(Pt A):314-323. doi: 10.1016/j.fct.2017.05.068. Epub 2017 May 30.

Abstract

Surfactants may cause dysfunction of intestinal tight junctions (TJs), which is a common feature of intestinal autoimmune diseases. Effects of dietary surfactants on TJ integrity, measured as trans-epithelial resistance (TEER), were studied in Caco-2 cell monolayers. Cytotoxicity was assessed as apical LDH leakage. Monolayers were apically exposed for 60 min to the dietary surfactants solanine and chaconine (SC, potato glycoalkaloids, 0-0.25 mM), perfluorooctane sulfonic acid (PFOS, industrial contaminant, 0-0.8 mM), and sucrose monolaurate (SML, food emulsifier E 473, 0-2.0 mM) separately and as a mixture. Dose-response modelling of TEER EC50 showed that SC were 2.7- and 12-fold more potent than PFOS and SML, respectively. The mixture was composed of 1 molar unit SC, 2.7 units PFOS and 12 units SML ("SC TEER equivalent" proportions 1:1:1). Mixture exposure (0-0.05 mM SC equivalents) dose-response modelling suggested additive action on TJ integrity. Increasing SC and SML concentrations caused increased LDH leakage, but PFOS decreased LDH leakage at intermediate exposure concentrations. In the mixture PFOS appeared to protect from extensive SC- and SML-induced LDH leakage. Complex mixtures of surfactants in food may act additively on intestinal TJ integrity, which should be considered in risk assessment of emulsifier authorisation for use in food production.

Keywords: Food additive; Glycoalkaloids; Leaky intestine; Mixture; PFOS; Sucrose monolaurate.

MeSH terms

  • Alkanesulfonic Acids / adverse effects
  • Alkanesulfonic Acids / pharmacology
  • Caco-2 Cells
  • Fluorocarbons / adverse effects
  • Fluorocarbons / pharmacology
  • Food Additives / adverse effects*
  • Food Additives / pharmacology
  • Humans
  • Intestines / drug effects*
  • L-Lactate Dehydrogenase / metabolism
  • Plant Extracts / adverse effects*
  • Plant Extracts / pharmacology
  • Solanine / adverse effects
  • Solanine / pharmacology
  • Solanum tuberosum / chemistry
  • Sucrose / adverse effects
  • Sucrose / analogs & derivatives
  • Sucrose / pharmacology
  • Surface-Active Agents / adverse effects*
  • Surface-Active Agents / pharmacology
  • Tight Junctions / drug effects*
  • Tight Junctions / metabolism

Substances

  • Alkanesulfonic Acids
  • Fluorocarbons
  • Food Additives
  • Plant Extracts
  • Surface-Active Agents
  • sucrose monolaurate
  • Solanine
  • Sucrose
  • perfluorooctane sulfonic acid
  • L-Lactate Dehydrogenase