Karolinska Stable Isotope Core (KSIC)

-Support for stable isotope tracer studies in collaborative projects-


We are a core facility for researchers at Karolinska Institutet and KarolinskaUniversityHospital in the sense that we help researchers with the use of stable isotope tracers in their clinical metabolic studies in collaborative projects. We are NOT a core facility that will analyse samples for a fee. If you are interested please contact me (


Stable isotope tracers are metabolites labelled with stable isotopes that can be used to quantify metabolic pathways in vivo. It is the only technique available to safely measure and actually quantify metabolic processes in human volunteers and patients in vivo. Examples of pathways that can be assessed are:


  • Glucose production and utilisation rates.
  • Whole body protein synthesis and breakdown rates.
  • Mitochondrial biogenesis rates.
  • Skeletal muscle or albumin synthesis rates.
  • Whole body lipolysis rates.


The support we give is in the study design, preparation of the tracers needed, analyses by mass spectrometry, data analyses and interpretation of the results. The research group has a longstanding expertise in these techniques especially in the clinical setting.

Check out some of the references we have been involved in:


  • Protein metabolism in leg muscle following an endotoxin injection in healthyvolunteers. Clin Sci (Lond). 2009;118(6):421-7. PubMed PMID: 19751216.


  • Circulatingand muscle glutathione turnover in human endotoxaemia. Clin Sci (Lond). 2009,117(9):313-9. PubMed PMID: 19265509.


  • Dysregulation of mitochondrial dynamics and themuscle transcriptome in ICU patients suffering from sepsis induced multiple organfailure. PLoS One. 2008;3(11):e3686. PubMed PMID: 18997871.


  • Randomized clinical trial of the effect of preoperative oral carbohydrate treatment on postoperative whole-body protein and glucose kinetics. Br J Surg.2007;94(11):1342-50. PubMed PMID: 17902094.


  • Enhanced in vivo protein synthesis in circulating immune cells ofICU patients. J Clin Immunol. 2007;27(6):589-97. PubMedPMID: 17619127.


  • Synthesis rates of total liver protein and albumin are both increased in patients with an acute inflammatory response. Clin Sci (Lond). 2006;110(1):93-9. PubMed PMID: 16144514.


  • Determination of in vivo protein synthesis in human palatine tonsil.Clin Sci (Lond). 2005;108(2):179-84. PubMed PMID: 15535800.


  • Intensive insulin treatment in critically ill trauma patients normalizes glucose by reducing endogenous glucose production. J Clin Endocrinol Metab. 2004;89(11):5382-6. PubMed PMID: 15531485.


  • Impact of surgical trauma on human skeletal muscle protein synthesis. Clin Sci (Lond). 2004;107(6):601-7. PubMed PMID: 15324310.


  • Insulin stimulated glucose disposal in peripheral tissues studied with microdialysis and  stable isotope tracers. Clin Nutr. 2004;23(4):743-52. PubMed PMID: 15297113.


  • Contractile protein breakdown in human leg skeletal muscle as estimated by [2H3]-3-methylhistidine: a new method. Metabolism. 2004;53(8):1076-80. PubMed PMID: 15281022.



Latest news/links


Check out our European Special Interest Group in tracer methods here!!



Want to know more?? Attend our course in may next year.