Congratulations to Jelena Branovets, who defended her doctoral thesis, Energetics and Calcium Handling in Hearts from Creatine-Deficient Mice, at TalTech on 29 September 2022.
The creatine kinase system helps the heart match energy production to the energy needed for every contraction. Jelena's thesis examined what happens when mice cannot produce creatine, using two models in which a different enzyme required for creatine synthesis is absent.
The work found that creatine deficiency caused only modest changes in cardiac metabolism and energy transfer, despite the central role usually attributed to creatine kinase. The effects depended on the model: altered regulation of mitochondrial energetics was observed only in hearts lacking arginine:glycine amidinotransferase (AGAT). More pronounced changes occurred in cardiomyocyte calcium dynamics and contractility, showing that the heart can adapt to a disrupted creatine kinase system in ways that extend beyond energy metabolism.
Jelena was supervised by Rikke Birkedal.