Impact of Blueberry Consumption on the Human Fecal Bileacidome: A Pilot Study

Cholesterol-derived bile acids (BAs) affect numerous physiological functions such as glucose homeostasis, lipid metabolism and absorption, intestinal inflammation and immunity, as well as intestinal microbiota diversity. Diet influences the composition of the BA pool. The present study analyzes the impact of a dietary supplementation with a freeze-dried blueberry powder (BBP) on the fecal BA pool composition. The diet of 11 men and 13 women at risk for metabolic syndrome was supplemented with 50g/day of BBP for 8 weeks, and feces were harvested before (pre) and after (post) BBP consumption. BAs were profiled using liquid chromatography coupled to tandem mass spectrometry. No significant changes in total BAs were detected when comparing pre- vs post-BBP consumption samples. However, post-BBP consumption samples exhibited significant accumulations of glycine-conjugated BAs (p=0.04), glycochenodeoxycholic (p=0.01) and glycoursodeoxycholic (p=0.01) acids, as well as a significant reduction (p=0.03) of the secondary BA levels, when compared to pre-BBP feces (p=0.03). In conclusion, the fecal bileacidome is significantly altered after the consumption of BBP for 8 weeks. While additional studies are needed to fully understand the underlying mechanisms and physiological implications of these changes, our data suggest that the consumption of blueberries can modulate toxic BAs elimination.