Selenium Status Is Associated with Inflammation in Epicardial Adipose Tissue in Elderly Patients with Coronary Artery Disease.

BACKGROUND

Inflammation in epicardial adipose tissue (EAT) contributes to cardiovascular disease through the local production of pro-inflammatory cytokines affecting the adjacent myocardium. Selenium (Se) is essential for selenoprotein-mediated antioxidant and anti-inflammatory functions. We investigated associations between Se status and inflammatory markers in EAT and in the circulation in patients with coronary artery disease (CAD).

METHODS

Patients with CAD undergoing coronary artery bypass grafting (n = 52) and valve disease patients receiving valve replacement serving as controls (n = 22) were included from the ATICH study. EAT biopsies were obtained during open-chest chest surgery. Serum Se was measured by inductively coupled plasma mass spectrometry. Associations between Se and EAT mRNA expression of Nod-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome components and cytokines, as well as circulating inflammatory markers, were assessed using Spearman's rho and group comparisons based on median Se levels.

RESULTS

Se concentrations were lower in CAD patients than controls (0.9 vs. 1.1 µmol/L, p = 0.025). In CAD patients, Se levels correlated with EAT expression of CASP1 and IL18, and with circulating IL-6. Se levels above the median were associated with lower EAT expression of CASP1 and NLRP3 and reduced IL-6 levels (p < 0.05, all). Our analysis of publicly available RNA seq data demonstrated selenoprotein's presence in EAT.

CONCLUSION

Lower Se status in CAD was associated with increased systemic and EAT inflammation, suggesting a role for selenoprotein-dependent antioxidant mechanisms in regulating cardiac adipose tissue inflammation.