Isotopic tracer techniques are used to interrogate metabolic processes, such as the turnover of endogenous carbohydrates, proteins or lipids by means of stable isotopes. Through this, changes in energy expenditure, relative fuel utilization, gluconeogenesis, and other aspects of metabolic substrate turnover can be monitored and quantified. Examples are provided below
- Endogenous glucose turnover rates measured at key times (e.g. during the basal state by tracer dilution using [6,6 2H2] glucose).
- Dual or triple tracer dilution techniques to estimate the relative contribution of exogenous and endogenous glucose sources to ambient blood glucose, such as during the postprandial state (tracers such as infusion of [6-3H] glucose and [6,6-2H2] glucose are combined with [1-13C] glucose-enriched meals). Multiple tracer methods can be used to study the efficacy of treatments that interfere with endogenous glucose absorption and / or urinary glucose excretion.
- De novo lipogenesis can be determined by stable isotopes, (e.g. labeled 13C-acetate or deuterated water [2H2O], which can be used to assess lipoprotein fluxes). Read More
- Lipolysis can be quantified by determining the rate of glycerol appearance, determined by a stable isotope tracer of glycerol such as 2H5.
