Exposure to nonylphenol in early life increases pro-inflammatory cytokines in the prefrontal cortex: Involvement of gut-brain communication

Chem Biol Interact. 2020 May 25:323:109076. doi: 10.1016/j.cbi.2020.109076. Epub 2020 Mar 30.

Abstract

A growing body of evidence indicates that exposure to nonylphenol (NP), a typical persistent organic pollutant (POP), in early life results in the impairment of the central nervous system (CNS), but the underlying mechanism still remains to be elucidated. High levels of pro-inflammatory cytokines in the brain have been implicated in the CNS damages. The animal model of exposure to NP in early life was established by maternal gavage during the pregnancy and lactation in the present study. We found that exposure to NP in early life increased the levels of pro-inflammatory cytokines in the rat prefrontal cortex. Interestingly, the levels of pro-inflammatory cytokines in the intestine as well as in the serum were also increased by NP exposure. Furthermore, the increased permeability of intestinal barrier and blood-brain barrier (BBB), two critical barriers in the gut to brain communication, was observed in the rats exposed to NP in early lives. The decreased expression of zonula occludens-1 (ZO-1) and claudin-1 (CLDN-1), tight junction proteins (TJs) that responsible for maintaining the permeability of intestinal barrier and BBB, was found, which may underlie these increases in permeability. Taken together, these results suggested that the disturbed gut-brain communication may contribute to the increased levels of pro-inflammatory cytokines in the prefrontal cortex caused by NP exposure in early life.

Keywords: Intestine; Nonylphenol; Prefrontal cortex; Pro-inflammatory cytokines.

MeSH terms

  • Animals
  • Animals, Newborn
  • Blood-Brain Barrier / drug effects
  • Blood-Brain Barrier / pathology
  • Cerebrospinal Fluid / metabolism
  • Claudin-1 / metabolism
  • Cytokines / blood
  • Cytokines / metabolism*
  • Female
  • Gastrointestinal Tract / drug effects
  • Gastrointestinal Tract / pathology*
  • Inflammation Mediators / blood
  • Inflammation Mediators / metabolism*
  • Intestines / drug effects
  • Intestines / pathology
  • Maternal Exposure
  • Permeability
  • Phenols / toxicity*
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / metabolism*
  • Prefrontal Cortex / pathology*
  • Pregnancy
  • Prenatal Exposure Delayed Effects / blood
  • Prenatal Exposure Delayed Effects / metabolism*
  • Prenatal Exposure Delayed Effects / pathology*
  • Rats, Sprague-Dawley
  • Zonula Occludens-1 Protein / metabolism

Substances

  • Claudin-1
  • Cytokines
  • Inflammation Mediators
  • Phenols
  • Zonula Occludens-1 Protein
  • nonylphenol