Evaluation of mTOR Activity in COPD Patients with Emphysema

Abstract

Objective: To evaluate the function of the mammalian target of the rapamycin (mTOR) pathway in chronic obstructive pulmonary disease (COPD) patients with emphysema. Study Design: Observational study. Place and Duration of Study: Department of Pulmonology, Mugla Training and Research Hospital, Turkey, from January to March 2022. Methodology: Thirty COPD patients and thirty healthy volunteers were included. Demographic data, pack-year of cigarette, spirometric values, and emphysema percentage (calculated with CT scan) were recorded. mTOR, raptor, and deptor were measured with ELISA method. Statistical significance was accepted as p0.05. Results: The mean value of mTOR in the COPD group was 3.48 2.01 ng/ml and it was significantly higher than the control (1.51 0.44 ng/ml). The mTOR was positively correlated with MMRC, annual exacerbation rate, emphysema percentage, and pack/year of cigarette and negatively correlated with SpO2 and FEV1. The significant relationship was found with only emphysema (B=0.067, SE=0.020, 95% CI=0.027-0.107, p=0.002). The cut-off value of mTOR for COPD was found as 1.815 ng/ml (sensivity=77%). Conclusion: Overexpression of mTOR and its signalling proteins have a significant role in emphysema development. Reduction of mTOR expression/activity might be helpful to control dyspnea severity, number of exacerbations, loss of FEV1, and progression of emphysema.