Dietary supplementation with inulin-propionate ester or inulin improves insulin sensitivity in adults with overweight and obesity with distinct effects on the gut microbiota, plasma metabolome and systemic inflammatory responses: a randomised cross-over trial

Chambers, E. S. et al. (2019) Dietary supplementation with inulin-propionate ester or inulin improves insulin sensitivity in adults with overweight and obesity with distinct effects on the gut microbiota, plasma metabolome and systemic inflammatory responses: a randomised cross-over trial. Gut, 68(8), pp. 1430-1438. (doi: 10.1136/gutjnl-2019-318424) (PMID:30971437) (PMCID:PMC6691855)

Abstract

Objective: To investigate the underlying mechanisms behind changes in glucose homeostasis with delivery of propionate to the human colon by comprehensive and coordinated analysis of gut bacterial composition, plasma metabolome and immune responses. Design: Twelve non-diabetic adults with overweight and obesity received 20 g/day of inulin-propionate ester (IPE), designed to selectively deliver propionate to the colon, a high-fermentable fibre control (inulin) and a low-fermentable fibre control (cellulose) in a randomised, double-blind, placebo-controlled, cross-over design. Outcome measurements of metabolic responses, inflammatory markers and gut bacterial composition were analysed at the end of each 42-day supplementation period. Results: Both IPE and inulin supplementation improved insulin resistance compared with cellulose supplementation, measured by homeostatic model assessment 2 (mean±SEM 1.23±0.17 IPE vs 1.59±0.17 cellulose, p=0.001; 1.17±0.15 inulin vs 1.59±0.17 cellulose, p=0.009), with no differences between IPE and inulin (p=0.272). Fasting insulin was only associated positively with plasma tyrosine and negatively with plasma glycine following inulin supplementation. IPE supplementation decreased proinflammatory interleukin-8 levels compared with cellulose, while inulin had no impact on the systemic inflammatory markers studied. Inulin promoted changes in gut bacterial populations at the class level (increased Actinobacteria and decreased Clostridia) and order level (decreased Clostridiales) compared with cellulose, with small differences at the species level observed between IPE and cellulose. Conclusion: These data demonstrate a distinctive physiological impact of raising colonic propionate delivery in humans, as improvements in insulin sensitivity promoted by IPE and inulin were accompanied with different effects on the plasma metabolome, gut bacterial populations and markers of systemic inflammation.

• Item Type: Articles
• Additional Information: This article presents independent research funded by the UK Biotechnology & Biological Sciences Research Council (BBSRC) (BB/L004259/1) and supported by the National Institute of Health Research (NIHR) Clinical Research Facility at Imperial College Healthcare NHS Trust. The Section of Endocrinology and Investigative Medicine is funded by grants from the UK Medical Research Council (MRC) and BBSRC, and is supported by the NIHR Imperial Biomedical Research Centre (BRC) Funding Scheme.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Preston, Professor Tom and Morrison, Professor Douglas
• Authors: Chambers, E. S., Byrne, C. S., Morrison, D. J., Murphy, K. G., Preston, T., Tedford, C., Garcia-Perez, I., Fountana, S., Serrano-Contreras, J. I., Holmes, E., Reynolds, C. J., Roberts, J. F., Boyton, R. J., Altmann, D. M., McDonald, J. A.K., Marchesi, J. R., Akbar, A. N., Riddell, N. E., Wallis, G. A., and Frost, G. S.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Gut
• Publisher: BMJ Publishing Group
• ISSN: 0017-5749
• ISSN (Online): 1468-3288
• Published Online: 10 April 2019
• Copyright Holders: Copyright © 2019 The Authors
• First Published: First published in Gut 68(8): 1430-1438
• Publisher Policy: Reproduced under a Creative Commons License