Glucocorticoid regulation of clinical and functional manifestations of asthma in patients with different airway response to hyposmolar stimulus during anti-inflammatory therapy

Abstract

Introduction. The role of an alternative adenylate cyclase pathway of hormonal signal transmission under the action of synthetic glucocorticosteroids with the participation of endogenous stress-limiting activity of the adrenal cortex in conjunction with the adaptive capabilities of airway homeostasis in patients with asthma under conditions of osmotic stress has not been studied at present. Aim. To assess the dynamics of cortisol and cyclic adenosin monophosphate (cAMP) in asthma patients with different airway responses to hypoosmolar stimuli when using anti-inflammatory combination therapy with inhaled corticosteroids/long-acting β2 -agonists (ICS/LABA). Materials and methods. 96 patients diagnosed with asthma received combined anti-inflammatory therapy with ICS/LABA for 24 weeks. Group 1 included patients (n=18) with airway hyperresponsiveness to hypoosmolar stimulus, group 2 (n=78) – with no reaction of the bronchi to a 3-minute ultrasonic inhalation of distilled water. At baseline and at the end of treatment, the lung function was studied; to assess the regulatory function of glucocorticoids using non-genomic signaling pathways, the levels of cortisol in blood serum and cAMP in blood leukocytes were determined. Results. Patients of group 1 in comparison with the second one initially had a lower FEV1 ‒ 88.2±5.3 and 98.5±1.7%, respectively (p<0.05), after treatment in both groups there was a slight tendency to an increase in FEV1 (98.5±5.7 and 101.4±2.5%, respectively, p>0.05). The concentration of cortisol and cAMP at baseline and after 24 weeks of therapy in patients of group 1 was 588.7±32.0 and 495.0±48.7 nmol/L, 61.7±5.1 and 76.5±5, 2 pmol/106 cells (p<0.01); in group 2 − 610.5±20.1 and 522.2±15.60 nmol/L (p<0.001), 76.2±2.2 and 90.6±2.5 pmol/106 cells (p<0.001). Conclusion. In asthma patients with airway osmotic hyperresponsiveness, persistent adaptation to osmotic stress is traced, which is combined with a more significant impairment of the lung function and indicates insufficient therapeutic control over glucocorticoid regulation of osmotic stress by the selected volume of ICS/LABA therapy.