Last update:
01-Feb-2021

OBJECTIVE To shed light on the effect of remote ischemic conditioning (RIC) on the properties of blood plasma of patients with acute myocardial infarction (AMI), using differential scanning calorimetry (DSC), which has recently emerged as a novel tool in biomedicine.

METHOD We used DSC to examine the protein denaturation heat capacity profiles of blood plasma samples, particularly of plasma albumin and immunoglobulins, collected from patients with acute myocardial infarction, before and after RIC intervention. DSC is a highly sensitive, non-invasive biophysical technique, which provides fast in situ monitoring of changes in the thermodynamic behavior of biological samples.

RESULTS A major finding of the study was the reduction of the albumin peak in the DSC profiles of the patients with AMI as a result of the RIC intervention, with the heat capacities ratio of the albumin to globulin peaks approaching the control (healthy) values. In contrast, when RIC was applied to healthy individuals, it produced no significant changes in the heat capacity profiles of their plasma proteins.

CONCLUSIONS RIC intervention had a beneficial effect on patients with AMI, bringing their blood plasma thermograms closer to those characterizing healthy individuals. Previous studies have proposed various mechanisms for the RIC beneficial effects and some reports suggest oxidative stress reduction as a possible mechanism mediating the RIC effects. However, since blood plasma oxidation has been previously reported to result in suppression of the albumin denaturation peak, the findings of the present study appear to disagree with the hypothesis that RIC exerts its beneficial effect through oxidative stress reduction.

Key words: Albumin, Blood plasma, Differential scanning calorimetry, Myocardial infarction, Remote ischemic conditioning.