Nitrogen Recycling Via Gut Symbionts Increases in Ground Squirrels over the Hibernation Season

Overview

Journal Science

Specialty Science

Date 2022 Jan 27

PMID 35084962

Authors

Matthew D Regan

Edna Chiang

Yunxi Liu

Marco Tonelli

Kristen M Verdoorn

Sadie R Gugel

Garret Suen

Hannah V Carey

Fariba M Assadi-Porter

Affiliations

Soon will be listed here.

Abstract

Hibernation is a mammalian strategy that uses metabolic plasticity to reduce energy demands and enable long-term fasting. Fasting mitigates winter food scarcity but eliminates dietary nitrogen, jeopardizing body protein balance. Here, we reveal gut microbiome-mediated urea nitrogen recycling in hibernating thirteen-lined ground squirrels (). Ureolytic gut microbes incorporate urea nitrogen into metabolites that are absorbed by the host, with the nitrogen reincorporated into the squirrel's protein pool. Urea nitrogen recycling is greatest after prolonged fasting in late winter, when urea transporter abundance in gut tissue and urease gene abundance in the microbiome are highest. These results reveal a functional role for the gut microbiome during hibernation and suggest mechanisms by which urea nitrogen recycling may contribute to protein balance in other monogastric animals.

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