Dietary fatty acid content influences the expression of genes involved in the lipid turnover and inflammation in mouse colon and spleen

Abstract

BackgroundDietary interventions can improve gastrointestinal (GI) symptoms. We determined the effects of fatty acids (FAs) supplementation with medium- and long-chain saturated FAs on mouse GI motility and correlated them with the expression of genes for free FA receptors (FFAR)1–4, FA binding protein 4 (FABP4) and inflammation.MethodsForty-eight BalbC were assigned to: standard diet (STD), diet rich in medium-chain saturated FAs (COCO) and long-chain saturated FAs (HF) (7% by weight). Body weight (BW) and food intake (FI) were monitored for 8-weeks. GI motility was determined by fecal pellet output (FPO) and colon bead expulsion tests. FABP4 inhibitor, BMS309403 (1 mg/kg, ip) was injected to half of each group 2 days/week. mRNA expression of FABP4, (FFAR)1–4, and pro-inflammatory cytokines were measured in colonic and splenic tissues using real-time PCR.ResultsCOCO and HF decreased FI. COCO accelerated overall GI transit (p < 0.05). COCO increased the mRNA expression of FFAR2 (p < 0.001) and TNFα (p < 0.01); HF increased the expression of FABP4 and FABP4 (p < 0.05), and FFAR2 (p < 0.001) in the colon, and decreased FFAR1 and FABP4 (p < 0.001), TNFα (p < 0.01) and IL-1ß (p < 0.05) in splenic tissues. BMS309403 decreased the FI and delayed colonic transit in STD+BMS and COCO+BMS vs. STD (p < 0.05). HF+BMS increased colonic expression of FFAR3 (p < 0.01), TNFα (p < 0.01), IL-6 (p < 0.01), and reduced FFAR4 (p < 0.05); COCO + BMS decreased TNFα (p < 0.01).ConclusionDiversification in the dietary lipid content affected GI motility in mice and the expression of FFARs and pro-inflammatory cytokines in vivo.