Nlrp3 Gene Expression in Circulating Leukocytes Declines During Healthy Aging.

Aging is often associated with elevated levels of low grade inflammation supposed to drive age-associated diseases. Here, we conducted a cross-sectional study on 58 healthy volunteers, aged from 19 to 81, to investigate the relationship between age and the expression of three inflammasome component genes (Nlrp3, Asc, Casp1), the up-stream transcription factor NFkB, and the pro-inflammatory cytokine Il-1β in leukocytes. We also assessed C-reactive protein (CRP) and IL-1β in plasma, as additional inflammatory markers. We did not find any support to the hypothesis that inflammasone activation increases with age. Expression of Asc, Casp1, NFkB, and Il-1β did not vary with age, body mass index (BMI), and CRP levels. In addition, expression did not differ between males and females or between smokers and non-smokers. A notable exception was the expression of Nlrp3 which varied non-linearly with age. Specifically, Nlrp3 expression strongly declined during aging, in subjects who were between 50 and 81 years old. CRP was higher in women and increased as a function of age-corrected BMI, while only four subjects showed detectable amount of IL-1β in plasma. Further work on larger cohorts with a longitudinal monitoring should be conducted to corroborate the finding that healthy aging is associated with a decrease in inflammasome activation.