PP447 - ALTERED EFFECTS OF INULIN SUPPLEMENTATION ON GUT MICROBIOTA COMPOSITION AND SCFA METABOLISM IN PATIENTS WITH COPD

PP447

ALTERED EFFECTS OF INULIN SUPPLEMENTATION ON GUT MICROBIOTA COMPOSITION AND SCFA METABOLISM IN PATIENTS WITH COPD

I. Minussi¹, B. Seethaler^2,*, S. K. Kirschner¹, M. P. Engelen¹, S. C. Bischoff², N. E. Deutz¹

¹Center for Translational Research in Aging & Longevity, Texas A&M University, College Station, United States, ²Institute of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany

Rationale: Fiber intake increases intestinal short-chain fatty acid (SCFA) production and is proposed as a strategy to reduce Chronic Obstructive Pulmonary Disease (COPD) symptoms and progression. We studied the effects of fibers on gut microbiota composition and SCFA metabolism in patients with COPD and healthy controls.

Methods: In a randomized, double-blind crossover study, 13 older patients with COPD (GOLD II-IV) and 40 healthy controls received inulin (from 10 to 30 g/d) or placebo (maltodextrin) for 7 days. We assessed gut microbiota composition (shotgun metagenomic sequencing) and injected [U-13C]-labeled SCFAs intravenously, measured its enrichments and calculated the sizes of the accessible (Q1), inaccessible (Q2) pools, production in Q1 (whole-body production (WBP)) and in Q2 (i.e. intestine and microbiota (intracellular production), and plasma and fecal SCFA concentrations (GC-MS/MS). For statistics we used R.

Results:  In healthy adults inulin reduced diversity (alpha: Shannon index -0.53, P<0.001) and (beta: R2=0.033; P=0.001) while in COPD diversity reduced less (alpha: -0.21, P=0.015) or was unchanged (beta: P=0.837). Inulin-induced changes in gut bacteria were mainly found in healthy adults (changes in 29 versus 2 species with FDR-adj. P<0.05). Baseline SCFA kinetics were similar between COPD and healthy controls (all P>0.2), though COPD had higher plasma isobutyrate (P=0.013) and 2-methylbutyrate (P=0.049). Inulin increased intracellular production of propionate by 18.4% in healthy controls (P=0.037), while in COPD it increased butyrate WBP by 43.6% and flux between pools by 43.8% (both P<0.001). Plasma and fecal acetate (P<0.001), fecal propionate (P=0.045), plasma (P=0.002) and fecal (P=0.023) butyrate concentrations increased in healthy controls but not in COPD (all P>0.2).

Conclusion: Patients with COPD have an altered response to inulin in gut microbiota and SCFA metabolism.

Disclosure of Interest: None declared