Impact of Plant-Based Dietary Fibers on Metabolic Homeostasis in High-Fat Diet Mice via Alterations in the Gut Microbiota and Metabolites

Elizabeth J Howard; Rachel K Meyer; Savanna N Weninger; Taylor Martinez; Hallie Wachsmuth; Marc Pignitter; Arturo Auñon-Lopez; Archana Kangath; Kalina Duszka; Haiwei Gu; Gabriele Schiro; Daniel Laubtiz; Frank A Duca

doi:10.1016/j.tjnut.2024.05.003

Impact of Plant-Based Dietary Fibers on Metabolic Homeostasis in High-Fat Diet Mice via Alterations in the Gut Microbiota and Metabolites

J Nutr. 2024 May 10:S0022-3166(24)00280-3. doi: 10.1016/j.tjnut.2024.05.003. Online ahead of print.

Authors

Affiliations

¹ School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ, United States.
² School of Nutritional Sciences and Wellness, University of Arizona, Tucson, AZ, United States.
³ Department of Physiology, University of Arizona, Tucson, AZ, United States.
⁴ Institute of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria.
⁵ Institute of Physiological Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria; Vienna Doctoral School in Chemistry (DoSChem), Faculty of Chemistry, University of Vienna, Vienna, Austria.
⁶ Department of Nutritional Sciences, University of Vienna, Vienna, Austria.
⁷ College of Health Solutions, Arizona State University, Phoenix, AZ, United States.
⁸ PANDA Core for Genomics and Microbiome Research, Steele Children's Research Center, University of Arizona, Tucson, AZ, United States.
⁹ School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ, United States; BIO5 Institute, University of Arizona, Tucson, AZ, United States. Electronic address: faduca@arizona.edu.

PMID: 38735572
DOI: 10.1016/j.tjnut.2024.05.003

Abstract

Background: The gut microbiota contributes to metabolic disease, and diet shapes the gut microbiota, emphasizing the need to better understand how diet impacts metabolic disease via gut microbiota alterations. Fiber intake is linked with improvements in metabolic homeostasis in rodents and humans, which is associated with changes in the gut microbiota. However, dietary fiber is extremely heterogeneous, and it is imperative to comprehensively analyze the impact of various plant-based fibers on metabolic homeostasis in an identical setting and compare the impact of alterations in the gut microbiota and bacterially derived metabolites from different fiber sources.

Objectives: The objective of this study was to analyze the impact of different plant-based fibers (pectin, β-glucan, wheat dextrin, resistant starch, and cellulose as a control) on metabolic homeostasis through alterations in the gut microbiota and its metabolites in high-fat diet (HFD)-fed mice.

Methods: HFD-fed mice were supplemented with 5 different fiber types (pectin, β-glucan, wheat dextrin, resistant starch, or cellulose as a control) at 10% (wt/wt) for 18 wk (n = 12/group), measuring body weight, adiposity, indirect calorimetry, glucose tolerance, and the gut microbiota and metabolites.

Results: Only β-glucan supplementation during HFD-feeding decreased adiposity and body weight gain and improved glucose tolerance compared with HFD-cellulose, whereas all other fibers had no effect. This was associated with increased energy expenditure and locomotor activity in mice compared with HFD-cellulose. All fibers supplemented into an HFD uniquely shifted the intestinal microbiota and cecal short-chain fatty acids; however, only β-glucan supplementation increased cecal butyrate concentrations. Lastly, all fibers altered the small-intestinal microbiota and portal bile acid composition.

Conclusions: These findings demonstrate that β-glucan consumption is a promising dietary strategy for metabolic disease, possibly via increased energy expenditure through alterations in the gut microbiota and bacterial metabolites in mice.

Keywords: dietary fiber; gut microbiota; metabolic homeostasis; metabolites; obesity.