In Vivo Desflurane Preconditioning Evokes Dynamic Alterations of Metabolic Proteins in the Heart - Proteomic Insights Strengthen the Link between Bioenergetics and Cardioprotection

Background: The cardioprotective effect of anaesthetic preconditioning as measured by reduction of ischaemia-reperfusion (I/R) injury is a well described phenomenon. However little is known about the impact on the myocardial proteome. We therefore investigated proteome dynamics at different experimental time points of a preconditioning protocol. Methods: Using an in vivo rat model of desflurane-induced preconditioning (DES-PC) cardiac tissue proteomes were analysed by a gel-based comparative approach. Treatment-dependent protein alterations were assessed by intra-group comparisons. Proteins were identified by mass-spectrometry. Results: A total of 40 protein spots were altered during the 30-minutes lasting preconditioning protocol. None of the proteins was differentially regulated consistently at all experimental time points. Interestingly, 1) the repeated administration of desflurane mostly accounted for proteome alterations during DES-PC, 2) the majority of altered protein species showed a decrease in abundance, 3) these changes primarily affected metabolic proteins involved in NADH/NAD + redox balance, calcium homeostasis and acidosis and 4) protein alterations were not exclusively due to expression changes but also represented modifications of specific protein isoforms. Conclusion: DES-PC evokes dynamic alterations in the cardiac proteome which substantiate a tight regulation of bioenergetic proteins. Unique protein modifications may play a more important role in the preconditioning response.