O-GlcNAcylation blood levels are increased in response to stress induced by cardiopulmonary bypass
Abstract
Introduction
Cardiopulmonary bypass (CPB) is a common procedure to maintain body perfusion during cardiac surgery. It is associated with a systemic inflammatory response, hemostasis and circulatory dysfunction that can lead to organ dysfunction and seldomly to death. O-GlcNAcylation is a post-translational modification modulated in response to stress in different acute and chronic situations.
Objective
Decipher if blood O-GlcNAc levels are modified during CPB induced stress.
Method
Vingt adult patients with CPB time > 60 minutes were included. Blood samples were collected on EDTA at (i) anesthesia induction (Ind), (ii) aortic declamping (AD) and (iii) 5 hours post-declamping (AD + 5). Whole blood and plasma were recovered from samples. O-GlcNAc levels in blood were evaluated by western blot while plasmatic biological markers were measured on automatic laboratory analysis system to correlate O-GlcNAc level with systemic response to CPB. Demographics and One-Way ANOVA analysis were performed with RStudio.
Results
CPB induced an early increase of plasmatic inflammatory marker IL-6 (Ind: 5.7 ± 3.2, AD: 120.0 ± 26.5 pg/mL, P < 0.01) that was sustained after 5 hrs. Systemic stress was confirmed via an increase in Creatine Kinase (Ind: 95.2 ± 12.2, AD: 271.9 ± 41.1 U/L, P < 0.001) and Lactate Dehydrogenase (AD: 316.3 ± 32.2, AD + 5: 541.2 ± 64.3 U/L, P < 0.001) release. Heart and renal markers demonstrated a dysfunction with Troponin T (AD: 656 ± 148, AD + 5: 1899 ± 568 pg/mL, P < 0.05) and Creatinine (AD: 94.8 ± 6.6, AD + 5:106.0 ± 7.14 μM, P < 0.05) respectively. CPB induced a significant 20% increase in O-GlcNAc levels (P < 0.01).
Conclusion
In this preliminary study, we highlighted that the inflammation and tissue stress consecutive to CPB are associated with an increase in blood O-GlcNAc levels 5 hours after CPB. Inclusion of more patients and correlations between O-GlcNAc level variation and demographics and/or patients’ outcome might reveal a new biomarker of risk after CPB.