Distal, not proximal, colonic acetate infusions promote fat oxidation and improve metabolic markers in overweight/obese men

Gut microbial-derived short-chain fatty acids (SCFA) are believed to affect host metabolism and cardiometabolic risk factors. The present study aim was to investigate the effects of proximal and distal colonic infusions with the SCFA acetate on fat oxidation and other metabolic parameters in men.In this randomized, double-blind cross-over trial, six overweight/obese men (BMI 25-35 kg/m2) underwent two experimental periods: one with distal and one with proximal colonic sodium acetate infusions. A feeding catheter was endoscopically positioned at the beginning of each period and remained in the colon for three consecutive test days, enabling colonic acetate (100 mmol/L or 180 mmol/L) or placebo infusion during fasting conditions and after an oral glucose load (postprandial). Fat oxidation and energy expenditure were measured using an open-circuit ventilated hood system and blood samples were repeatedly collected for 2h during fasting and postprandial conditions.Distal colonic 180 mmol/L acetate infusions increased fasting fat oxidation (1.78±0.28 vs -0.78±0.89 g fat 2h-1, P =0.015), fasting peptide YY (PYY, P =0.01) and postprandial glucose and insulin concentrations ( P <0.05), and tended to increase fasting plasma acetate ( P =0.069) compared with placebo. Distal 100 mmol/L acetate administration tended to decrease fasting tumor necrosis factor-α ( P =0.067) compared with placebo. In contrast, proximal colonic acetate infusions showed no eff...
Source: Clinical Science - Category: Biomedical Science Authors: Tags: PublishAheadOfPrint Source Type: research