The Influence of Diet Change and Oral Metformin on Blood Glucose Regulation and the Fecal Microbiota of Healthy Horses.
Abstract: Common treatments for Equine Metabolic Syndrome (EMS) and associated conditions include removal from pasture and adoption of an all-hay diet. Pharmacological treatments for EMS include metformin, a biguanide antihyperglycemic agent also administered to people to help improve glucose tolerance and insulin sensitivity. Both treatments may work, at least partially, through the gut microbiota, yet little is known regarding these effects in the equine host. To determine the influence on the fecal microbiota of this diet change and administration of metformin, six healthy horses were removed from pasture and switched to an all-hay diet, with four of those horses also receiving oral metformin for seven days. Control horses ( = 24) remaining on pasture and receiving no metformin were sampled at the beginning and end of one week. All samples were subjected to 16S rRNA sequencing, and horses undergoing the diet change were subjected to an oral sugar test twice, one week apart. Characteristic changes in the microbiota following diet change included the significant expansion of the phylum Kiritimatiellaeota. As Kiritimatiellaeota are related to Verrucomicrobia, found to expand in the microbiota of mice and humans in response to metformin, this taxon may represent the cognate microbes in equine hosts.
Publication Date: 2021-04-01 PubMed ID: 33915682PubMed Central: PMC8065426DOI: 10.3390/ani11040976Google Scholar: Lookup
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- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research explores how changes in diet and use of metformin, a medication to manage blood sugar, impact blood glucose regulation and the composition of gut bacteria in healthy horses. The study’s findings may shed light on ways to manage equine metabolic syndrome.
Background
- The central aspect of this research revolves around Equine Metabolic Syndrome (EMS), a health condition in horses that is often addressed by changing the animal’s diet from pasture grazing to a hay-based diet.
- Another common treatment approach is the administration of metformin, a drug typically used to manage glucose levels and increase insulin sensitivity, more often seen in human diabetes treatment. The theory is that both these treatments can exert their beneficial effects through alterations of the gut microbiota. However, the underlying impacts of these treatments on gut microbiota in horses are not well understood.
Methods
- In this research, the authors sought to investigate these effects by studying six healthy horses that were switched from a grazing pasture to a hay-based diet. Four of these horses also received oral metformin for a week.
- A control group of horses (n=24) that remained on pasture and did not receive metformin were also studied. Samples were collected from each horse at the start and end of the week. The horses undergoing the dietary shift were also subjected to an oral sugar test twice during the week, each test a week apart.
- All samples were tested using 16S rRNA sequencing to understand the impact on the microbiota.
Findings
- Results of the study showed that the changes made to the horses’ diet and the introduction of metformin significantly expanded the presence of the bacterial group Kiritimatiellaeota in the gut microbiota.
- The importance of this finding lies in the understanding that Kiritimatiellaeota are related to Verrucomicrobia, another group of bacteria known to multiply in response to metformin treatment in mice and humans.
- Hence, it can be inferred that Kiritimatiellaeota could play a similar role in the equine system, potentially mediating positive metabolic changes induced by diet management and metformin therapy in horses with EMS.
Cite This Article
APA
Ericsson AC, Johnson PJ, Gieche LM, Zobrist C, Bucy K, Townsend KS, Martin LM, LaCarrubba AM.
(2021).
The Influence of Diet Change and Oral Metformin on Blood Glucose Regulation and the Fecal Microbiota of Healthy Horses.
Animals (Basel), 11(4), 976.
https://doi.org/10.3390/ani11040976 Publication
Researcher Affiliations
- University of Missouri Metagenomics Center, Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65201, USA.
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
Conflict of Interest Statement
The authors have no conflict or competing interest.
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Citations
This article has been cited 2 times.- Weinert-Nelson JR, Biddle AS, Sampath H, Williams CA. Fecal Microbiota, Forage Nutrients, and Metabolic Responses of Horses Grazing Warm- and Cool-Season Grass Pastures.. Animals (Basel) 2023 Feb 22;13(5).
- Weinert-Nelson JR, Biddle AS, Williams CA. Fecal microbiome of horses transitioning between warm-season and cool-season grass pasture within integrated rotational grazing systems.. Anim Microbiome 2022 Jun 21;4(1):41.
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