Extended indirect calorimetry with isotopic CO₂ sensors for prolonged and continuous quantification of exogenous vs. total substrate oxidation in mice.

ABSTRACT: Indirect calorimetry (InCa) estimates whole-body energy expenditure and total substrate oxidation based on O₂ consumption and CO₂ production, but does not allow for the quantification of oxidation of exogenous substrates with time. To achieve this, we incorporated ¹³CO₂ and ¹²CO₂ gas sensors into a commercial InCa system and aimed to demonstrate their performance and added value. As a performance indicator, we showed the discriminative oscillations in ¹³CO₂ enrichment associated with food intake in mice fed diets containing naturally low (wheat) vs high (maize) ¹³C enrichment. To demonstrate the physiological value, we quantified exogenous vs total carbohydrate and fat oxidation continuously,

SUBMITTER: Fernandez-Calleja JMS 

PROVIDER: S-EPMC6687832 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature