Indirect calorimetry (InCa) is a non-invasive method that can potentially be used to assess metabolic health. To test this, we compared three InCa-based methods using aged and adult C57BL/6J male mice (72 and 10 weeks old) and assessed the stability of the responses over time. The aged and adult mice differed in adiposity and white adipose tissue mitochondrial density, indicative of a compromised metabolic health of the aged mice. In method 1, diurnal patterns of respiratory exchange ratio (RER) were followed for 24hrs under standard conditions. In method 2, fasted mice received glucose to test effective switching in substrate oxidation. In method 3, mice were exposed to oxygen restriction (OxR, 14.5 % O2) to test how effectively animals switch from normal to low oxygen availability. Each method was repeated with at least a 10 week interval to assess response stability. Method 1 was not stable in time. Method 2 did not reveal differences in metabolic health between adult and aged mice. Method 3 appeared most sensitive to detect differences between both groups and in each period. Adult mice maintained reduced oxygen consumption under OxR, while aged mice did not. Thus, the response to OxR is a sensitive and reproducible method to non-invasively measure metabolic health in mice. Molecular analyses showed that OxR affected glucose and lactate metabolic pathways in liver and adipose tissue, supporting the observed differences in oxygen consumption.
|Title of host publication||Abstracts 20th International Congress of Nutrition|
|Place of Publication||Basel|
|Publication status||Published - 2013|
|Event||20th International Congress of Nutrition, Granada, Spain - |
Duration: 15 Sep 2013 → 20 Sep 2013
|Conference||20th International Congress of Nutrition, Granada, Spain|
|Period||15/09/13 → 20/09/13|