Could NLRP3–inflammasome be a cardiovascular risk biomarker in acute myocardial infarction patients?

Abstract

Conventional cardiovascular risk factors (CVRFs) are accepted to identify asymptomatic individuals with high risk of acute myocardial infarction (AMI). However, AMI affects many patients previously classified at low risk. New biomarkers are needed to improve risk prediction. We propose to evaluate the NLRP3–inflammasome complex as a potential conventional cardiovascular risk (CVR) indicator in healthy males and post-AMI patients and compare both groups by known CVRFs. We included 109 men with no history of cardiovascular disease (controls) and 150 AMI patients attending a cardiac rehabilitation program. AMI patients had higher mean of body mass index (BMI) and waist circumference than the controls. However, high percentages of the controls had a high BMI and a waist circumference >95 cm. The controls also had higher systolic blood pressure (p > 0.001), total and low-density lipoprotein cholesterol, dietary nutrient, and calorific intake. Fuster BEWAT score (FBS) correlated more closely than Framingham risk score (FRS) with most CVRF, groups. However, only the FBS showed a correlation with inflammasome cytokine interleukin 1β (IL-1β). Several CVRFs were significantly better in AMI patients; however, this group also had higher mRNA expression of the inflammasome gene NLRP3 and lower expression of the autophagy gene MAP-LC3. The controls had high levels of CVRF, probably reflecting unhealthy lifestyle. FBS reflects the efficiency of strategies to induce lifestyle changes such as cardiac rehabilitation programs, and could provide a sensitive evaluation CVR. These results lead to the hypothesis that NLRP3–inflammasome and associated IL-1β release have potential as CVR biomarkers, particularly in post-AMI patients with otherwise low risk scores.