Maternal obesity induced by a 'cafeteria' diet in the rat does not increase inflammation in maternal, placental or fetal tissues in late gestation

Placenta. 2016 Mar:39:33-40. doi: 10.1016/j.placenta.2016.01.002. Epub 2016 Jan 6.

Abstract

Introduction: Obesity during pregnancy can cause serious complications for maternal and infant health. While this has often been attributed to increased inflammation during obese pregnancy, human and animal studies exhibit variable results with respect to the inflammatory status of the mother, placenta and fetus. Cafeteria (CAF) feeding induces more inflammation than standard high-fat feeding in non-pregnant animal models. This study investigated whether maternal obesity induced by a CAF diet increases maternal, fetal or placental inflammation.

Methods: Maternal obesity was established in rats by 8 weeks of pre-pregnancy CAF feeding. Maternal plasma inflammatory markers (IL-1β, IL-6, IL-10, IL-12p40, MCP1, GRO/KC, MIP-2 and TNFα) and expression of inflammatory genes (Tnfα, Il-6, Il-1β, Tlr2, Tlr4, Cox2 and Emr1) in maternal, placental and fetal tissues were measured at day 21 of gestation.

Results: Despite CAF animals having 63% more central body fat than controls at day 21 of gestation, plasma inflammatory markers were not increased; indeed, levels of IL-6, IL-12p40 and MIP2 were reduced slightly. Similarly, inflammatory gene expression remained largely unaffected by CAF feeding, except for slight reductions to Tlr4 and Emr1 expression in CAF maternal adipose tissue, and reduced Tlr4 expression in male labyrinth zone (LZ). The junctional zone (JZ) displayed increased Il-6 expression in CAF animals when fetal sexes were combined, but no inflammatory genes were affected by the CAF diet in fetal liver.

Conclusions: Maternal obesity induced by a CAF diet before and during pregnancy does not increase the inflammatory status of the mother, placenta or fetus in late gestation.

Keywords: Cafeteria-feeding; Cytokines; Inflammation; Obesity; Placenta; Pregnancy.

MeSH terms

  • Animals
  • Diet, High-Fat* / adverse effects
  • Female
  • Fetus / metabolism
  • Fetus / pathology
  • Gestational Age
  • Inflammation / etiology*
  • Inflammation / metabolism
  • Inflammation / pathology
  • Inflammation Mediators / metabolism
  • Male
  • Maternal Nutritional Physiological Phenomena*
  • Obesity / etiology
  • Obesity / immunology*
  • Obesity / metabolism
  • Placenta / metabolism
  • Placenta / pathology
  • Pregnancy
  • Pregnancy Complications / etiology
  • Pregnancy Complications / immunology*
  • Pregnancy Complications / metabolism
  • Rats

Substances

  • Inflammation Mediators