Modulation of Gut-Brain Axis Improves Microbiome, Metabolism, and Mood

Abstract

Objective: There is a close bidirectional relationship between overweight/obesity and depression, which may be largely modified through the microbiome and the gut-brain axis. Previous research has shown targeted weight loss effects and anti-depressive benefits of diets high in fiber and phytonutrients and low in sugar and processed foods. Thus, our objective was to determine changes in parameters common to both obesity and depression (e.g., microbiome balance, metabolic biomarkers, and psychological mood state) following a coordinated supplementation regimen combining probiotics, prebiotics, and phytonutrients (“phytobiotics”).

Methods: Thirty-three (33) healthy subjects participated in a 6-week supplementation trial (Amare “Project b3”) containing a targeted blend of probiotics, prebiotics, and phytobiotics. Microbiome balance was assessed in fecal samples using a novel PCR-based analysis (BiomeTracker) that has previously compared favorably to 16S sequencing. Biomarkers, including blood lipids, glucose, cortisol, and butyrate kinase, were assessed as indicators of effects on cardiovascular, inflammatory, and energy metabolism. Psychological mood state was assessed using the validated Profile of Mood States survey (POMS) to generate scores for Global Mood State and six sub-scales (Depression, Tension, Fatigue, Anger, Confusion, and Vigor).

Results: Following supplementation, there was a significant increase in populations of “good” bacteria (+8% Bifidobacterium, +33% Lactobacillus, +62% S. Thermophilus, +90% Akkermansia) as well as bacterial ratios associated with a healthier “obesity-resistant” metabolism (+6% composite score, -11% Firmicutes, +6% Bacteroidetes, -14% F/B ratio). Metabolites associated with stress and glycemic control improved post-supplementation (-11% cortisol; +89% butyrate kinase, -6% glucose), as did body fat (-2%) and blood lipids (-8% total cholesterol, -5% LDL, +3% HDL, -23% triglycerides, -7% TC/HDL). Psychological indices were significantly improved post-supplementation for both positive (+17% Global Mood; +23% Vigor) and negative mood states (-38% Depression; -41% Tension; -42% Fatigue; -31% Confusion; -39% Anger).

Conclusions: These results demonstrate the close relationship between microbiome balance, systemic metabolism, and psychological parameters – and the utility of targeted supplementation to optimize gut-brain-axis balance for both improved metabolism and enhanced mental wellness.

Keywords: Obesity; Depression; Anxiety; Stress; Probiotics; Prebiotics; Diet; Supplement