Autologous fecal microbiota transplantation can retain the metabolic achievements of dietary interventions.

Background: We recently reported that autologous fecal microbiota transplantation (aFMT), derived from the time of maximal weight-loss and administrated in the regain-phase, might preserve weight loss and glycemic control in moderately obese subjects, and is associated with specific microbiome signatures. Here, we sought to explore the global effect of aFMT on adipokines, inflammatory markers and blood cholesterol and on the overall gut microbiome preservation.

Methods: In the DIRECT-PLUS weight-loss trial, abdominally obese participants were randomized to three distinct weight-loss diets. Following the expected weight loss phase (0-6 m), 90 participants were randomized to receive their personal frozen fecal microbiota or placebo oral capsules (ten 1 g-capsules over ten sessions-total=100 g) during the expected weight regain phase (8-14 m).

Results: Of the 90 participants (age=52 yr; 0-6 m weight loss=-8.3 kg), 95.6% ingested at least 80/100 oral aFMT/placebo capsules over 6 months. Overall, the gut microbiome community structure was associated with plasma levels of leptin, cholesterol and interleukin-6 at baseline and after 6 m, whereas 6 m (weight loss phase) changes in specific microbiome species associated with the dynamic of leptin and inflammatory biomarkers. Following the 8-14 m aFMT administration phase, aFMT maintained decreased levels of leptin (ΔaFMT=-3.54 ng/mL vs. Δplacebo=-0.82 ng/mL;P = 0.04), C-reactive-protein (ΔaFMT=-1.45 mg/L vs. Δplacebo=-0.66 mg/L;P = 0.009), Interleukin-6 (ΔaFMT=-0.03pg/mL vs. Δplacebo=1.11pg/mL;P = 0.03) and total cholesterol (ΔaFMT=2.2 mg/dl vs. Δplacebo=13.1 mg/dl;P = 0.04) achieved in the weight loss phase. Overall, aFMT induced a significant preservatory effect on personal gut microbiome global composition (P = 0.03;Jensen-Shannon distance), as compared to placebo.

Conclusions: aFMT treatment in the regain phase might retain weight-loss induced metabolic benefits. These findings may suggest a novel aFMT treatment approach for personal metabolic attainment preservation.