(OR18-04-25) Effects of Chronic Intake of Berry (Poly)phenols With and Without Fructo-Oligosaccharide on Secondary Bile Acids

Objectives: This research assessed changes in secondary bile acids (BA) in adults with low-grade inflammation as part of a larger study aimed to understand the role of host- and gut-derived metabolites in mechanisms of inflammation.

Methods: In this 4-week randomized, parallel, single-blinded, placebo-controlled study (Clinicaltrials.gov NCT04100200), participants (n=92, hs-CRP >1.0 mg/L, Age: 35 ± 13 years, BMI: 29.8 ± 4.5 kg/m2; mean ± SD) consumed one of four beverages as part of their daily diet: mixed berries (MB), fructo-oligosaccharide (FOS), MB + FOS or a control. Fasting blood samples and fecal samples were collected at baseline (Day 0) and at the end of the study (Day 28). Secondary BA composition of plasma and fecal samples was assessed using UHPLC-QQQ-MS. Statistical analyses were performed using SAS 9.4 (SAS Institute, Inc., Cary, NC, USA).

Results: Preliminary analyses were focused on secondary BAs, specifically deoxycholic acid (DCA) and lithocholic acid (LCA). Plasma concentrations of LCA were below the limit of quantification and omitted from analysis, and no significant changes in plasma DCA were observed with any intervention. Alternatively, fecal DCA significantly decreased in the MB group (Day 0: 55.9 ± 8.6 nmol/L, Day 28: 38.9 ± 5.4 nmol/L; p=0.035) and significantly increased in the control group (Day 0: 33.4 ± 5.3 nmol/L, Day 28: 49.6 ± 7.1 nmol/L; p=0.027). Similarly, fecal LCA decreased with intake of MB (Day 0: 35.4 ± 3.9 nmol/L, Day 28: 22.8 ± 3.1 nmol/L; p=0.002), and increased with control intake (Day 0: 16.9 ± 3.1 nmol/L, Day 28: 24.0 ± 2.6 nmol/L; p=0.045). Delta changes (Day 28-Day 0, Δ) between interventions indicated Δ LCA and Δ DCA after MB and MB + FOS were different from FOS and control responses (p < 0.05 for all), but not different from each other. No differences were observed between the FOS and control groups.

Conclusions: These findings suggest MB modulates secondary BA metabolism by reducing concentrations of pro-inflammatory BAs, potentially due to gut microbiota activity. Further research, including metagenomic analyses, is needed to explore the mechanisms underlying these effects.

Funding Sources: This work is supported by Agricultural and Food Research Initiative {grant no. 2019-67017-29254/project accession no. 1018625} from the USDA National Institute of Food and Agriculture.