Age-Related Changes in the T Helper 17 and Regulatory T Cell-Related Cytokines During Cardiac Surgery

The age-associated dysregulated immune response may partly contribute to the greater mortality and morbidity in elderly patients undergoing cardiopulmonary bypass (CPB). The aim of the present study was to first investigate the possible relation between age and levels of interleukin (IL)-17 and IL-35 in CPB patients.

In general, 90 patients undergoing CPB from February 2018 to March 2019 in Jorjani Heart Center, Bandar Abbas, were enrolled in this cross-sectional study. IL-35 and IL-17A were measured before and 12 hours after CPB using enzyme-linked immunosorbent assay. The relation of age and the mentioned cytokines was assessed in patients < 70 and ≥ 70 years old.

IL-17A levels were slightly increased (25.7 ± 8.7 ng/mL versus 20.9 ± 6.3 ng/mL), while IL-35 levels represented a slight decrease (20.6 ± 10 ng/mL versus 23.2 ± 11.9 ng/mL) in CPB patients ≥ 70 years in comparison with those below 70 years (P > 0.05). There was a positive correlation between IL-17 and age (r = 0.4, P = 0.002) in patients older than 70 years. Eventually, IL-35 was negatively associated with age (r = -0.2, P = 0.03) in ≥ 70 years patients.

These data suggested that the age-related elevation of IL-17A levels, as well as a decline in the IL-35 serum concentration, contributing to the imbalanced pro- and anti-inflammatory response, may play a crucial role in the stronger adverse post-CPB outcomes in the elderly.