l-[1-13C]leucine

l-[1-13C]leucine is a stable isotope-labeled variant of the essential branched-chain amino acid L-leucine, where the carbon atom at the carboxyl (C1) position is replaced with the non-radioactive carbon-13 isotope. It is primarily used as a metabolic tracer in clinical research to quantify protein turnover, specifically the fractional synthesis rate (FSR) of proteins in various tissues such as skeletal muscle. By measuring the enrichment of the isotope in plasma, intracellular pools (like alpha-ketoisocaproate), and incorporated protein via mass spectrometry, researchers can calculate rates of protein synthesis, breakdown, and oxidation. This tracer is particularly valuable in studying muscle-wasting conditions, metabolic disorders, and the effects of aging or disease on protein metabolism, as it allows for safe, non-invasive tracking of amino acid kinetics in humans.

Other names

13C-leucine[1-13C]leucineL-leucine-1-13CL-leucine1-13CL-leucine 1-13C1-13C-L-leucineL-[1-13C]leucine