Maternal obesity changes the small intestine endocannabinoid system and fecal metabolites of weanling rats associated with reduced intestinal permeability and impaired glucose homeostasis.

Abstract

Purpose: The small intestine, including the endocannabinoid system (ECS), regulates the energy homeostasis. If maternal obesity modifies the intestinal ECS of the offspring favoring metabolic disorders throughout life is unexplored. Regardless maternal insults, overaction of the ECS has been related to obesity, mainly via type 1 cannabinoid receptor (CB1) signaling, while type 2 cannabinoid receptor (CB2) signaling and the endocannabinoid-like compounds, such as oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), have been associated with anti-inflammatory effects. We hypothesized that maternal obesity changes the ECS in the small intestine of weanling rat offspring in a sex-specific manner associated with altered fecal metabolites.

Methods: Female rats received a control diet (C; 9% fat) or an obesogenic diet (OD; 37.2% fat, 11.8% sucrose) 9 weeks before mating, gestation and lactation. Offspring were euthanized at weaning.

Results: Maternal obesity increased CB2 protein content and mRNA levels of monocyte chemoattractant protein-1 in the small intestine in male offspring, while decreased fecal content of PEA and OEA in both sexes. Maternal obesity decreased gut permeability, but impaired glycemic homeostasis. Concerning fecal levels of γ-aminobutyric acid, amino acids and hypoxanthine, maternal obesity induced a fecal signature related to inflammatory and glycemic homeostasis impairment and dysbiosis.

Conclusions: Maternal obesity induced intestinal inflammation and the signaling of CB2, PEA, and OEA might be part of a counter-regulatory response, contributing to reduced gut permeability, but not enough to avoid overweight and glycemic impairment in the offspring at weaning. Our findings provide molecular insights into the intestinal and fecal biomarkers for metabolic disorders.