SIRT1 and FOXO1 mRNA expression in PBMC correlates to physical activity in COPD patients

Background: Physical activity (PA) is considered as one of the most important prognostic predictors in chronic obstructive pulmonary disease (COPD) patients. Longevity gene, SIRT1, is reported to be involved in the pathogenesis of COPD by regulating the signaling pathways of oxidative stress, inflammation, and aging. We hypothesize that SIRT1 and related genes are also associated with the benefits of PA in COPD patients. Methods: Eighteen COPD outpatients were enrolled in this study, and their PA level was assessed with an accelerometer. We assessed the SIRT1 and related genes mRNA expression levels in the peripheral blood mononuclear cells (PBMCs) of the subjects. We carried out respiratory function testing, blood gas analysis, the 6-minute walk test, and measurement of the cross-sectional area of the erector spinae muscles (ESMCSA) by chest computed tomography. We analyzed the association of PA with the results of each of the examinations. Results: The mean age was 72±9 years, and the mean forced expiratory volume in 1 second was 1.4±0.56 L (52%±19% predicted). Our findings revealed a correlation between the daily PA and ESMCSA. The SIRT1 and Forkhead box O (FOXO)1 mRNA expression levels in PBMCs were positively correlated with moderate-PA time (r=0.60, p=0.008 for SIRT1 and r=0.59, p=0.01 for FOXO1).