ASPO Abstracts

Fecal Akkermansia muciniphila is associated with body composition and microbiome alpha diversity in overweight and obese women with breast cancer participating in a presurgical weight loss trial

Authors: Fruga AD, Van Der Pol W, Tsuruta Y, Rogers LQ, Morrow CD, Demark-Wahnefried W

Category: Lifestyles Behavior, Energy Balance & Chemoprevention, Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2018

Abstract Body:
Background: Akkermansia muciniphila is a beneficial gram-negative mucin-degrading bacterial species inhabiting the gastrointestinal tract that has been associated with host phenotypes and disease states in preclinical models and humans. This secondary analysis of a randomized controlled weight loss trial in breast cancer patients sought to explore characteristics of women with low (LAM) vs. high (HAM) A. Muciniphila relative abundance. Methods: Thirty-two women (body mass index >25) were randomized to hypocaloric diet and aerobic exercise to achieve 1kg weekly weight loss (n=17) or attention control (n=15) between their time of diagnosis with early stage (0-II) breast cancer until lumpectomy. Two-24 hour dietary recalls were collected at baseline and follow-up in conjunction with dual x-ray absorptiometry (DXA) and collection of fecal samples. Bacterial DNA was isolated and the V4 region of the 16S RNA gene was PCR-amplified and analyzed. Differences between study arms and between LAM and HAM were analyzed using t-tests for normally distributed data and non-parametric tests were used for microbiome data analysis. Results: Participants were 61±9 (mean±SD) years old, and received the intervention 30±9 days. At baseline, LAM had lower bodyweight (97.0±13.6 kg vs. 85.4±17.6 kg, p=0.046) and fat mass (46.4±9.0 kg vs. 38.9±11.2 kg, p=0.044) than HAM. Differences persisted between LAM and HAM in bodyweight (p=0.0048) and fat mass (p=0.039) at follow-up. Alpha diversity, measured by species richness, was higher in HAM (360.8±84.8 vs. 282.4±69.6, p=0.008) at baseline, which was slightly attenuated at follow-up (p=0.58). Change in total dietary fiber was positively associated with change in A. Muciniphila in LAM (ρ=0.626, p=0.002), but not HAM (ρ=0.436, p=0.180). Conclusion: A. Muciniphila may mediate the effects of dietary fiber in improving microbiome composition through dietary intervention.

Keywords: diet, exercise, breast cancer, gut microbiome