Hepatic Mitochondrial Oxidation breath test

The Hepatic Mitochondrial Oxidation breath test is a non-invasive diagnostic procedure used to evaluate the functional capacity and metabolic activity of mitochondria within the liver. This test typically involves the administration of a substrate labeled with a stable isotope, most commonly [1-13C]ketoisocaproate (KIC) or [1-13C]octanoate. Upon administration, the substrate undergoes specific mitochondrial oxidation; for example, KIC is decarboxylated by the branched-chain alpha-keto acid dehydrogenase (BCKDH) complex located in the mitochondrial matrix. This process releases 13CO2, which is subsequently exhaled and measured in the breath using isotope-ratio mass spectrometry or infrared spectroscopy. The rate of 13CO2 excretion serves as a surrogate marker for hepatic mitochondrial oxidative function. In clinical research, such as studies conducted by the University of Edinburgh, this test is utilized to investigate metabolic flexibility and energy expenditure changes in patients with Type 1 Diabetes, particularly following interventions like islet transplantation.

Other names

13C-KIC breath test13C-ketoisocaproate breath testketoisocaproate breath test13C-KICBT