Methylprednisolone Does Not Enhance Paraoxonase 1 Activity During Cardiopulmonary Bypass Surgery—A Randomized, Controlled Clinical Trial

Abstract

ObjectivesCardiopulmonary bypass (CPB) is linked to systemic inflammatory responses and oxidative stress. Paraoxonase 1 (PON1) is an antioxidant enzyme with a cardioprotective role, whose activity is decreased in systemic inflammation, and in patients with acute myocardial and global ischemia. Glucocorticoids counteract the effect of oxidative stress by up-regulating PON1 gene expression. We aimed to determine the effect of methylprednisolone on PON1 activity during cardiac surgery on CPB. DesignProspective, randomized, controlled clinical trial. SettingThe study was conducted at the University Medical Centre Ljubljana, Slovenia. Participants40 adult patients, who underwent complex cardiac surgery on CPB between February 2016 and December 2017, were randomized into methylprednisolone and control group (n=20 each). InterventionsPatients in the methylprednisolone group received 1g of methylprednisolone in the CPB priming solution, while patients in the control group were not given methylprednisolone during CPB. Measurements and Main ResultsWe compared the effect of methylprednisolone from CPB priming solution with standard care during CPB on PON1 activity until the 5. postoperative day. Correlations of PON1 activity with lipid status, mediators of inflammation, and hemodynamics were analyzed as well. No significant differences existed between study groups for PON1 activity, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) in any of the measurement intervals (p>0.016). Methylprednisolone group had significantly lower TNF-a (p<0.001), IL-6 (p<0.001), as well as CRP and procalcitonin (p<0.016) after surgery. No significant difference was found between groups for hemodynamic parameters. A positive correlation existed between PON1 and lipid status, whereas a negative correlation was found between PON1 activity and TNF-a, IL-6, as well as CPB duration. ConclusionsMethylprednisolone doesn't influence PON1 activity during cardiac surgery on CPB.