Pathogenesis of immune cell membrane abnormalities in comorbidity of chronic obstructive pulmonary disease and asthma

Abstract

The objective of this study was to investigate a role of fatty acid content in leukocyte membranes, oxylipin level and membrane potential of leukocyte membranes in the pathogenesis of immune cell membrane abnormalities in patients with comorbidity of asthma and chronic obstructive pulmonary disease (COPD). Methods. The study involved 39 patients with COPD, 41 patients with asthma, and 18 patients with comorbidity of COPD and asthma, and 28 healthy volunteers as controls. Fatty acid content of leukocyte membranes was investigated using gas-liquid chromatography. Thromboxane B2 and leukotriene B4 levels were measured using enzyme immunoassay. Mitochondrial membrane potential in leukocytes was measured ex tempore by cytofluorimetry. Statistically significant difference between mean values was determined by Student's t-test. Results. The comorbidity of COPD and asthma was characterized by accumulation of saturated fatty acids (12 : 0; 16 : 0; 18 : 0; 20 : 0) in leukocyte membrane and reduction in n-6 and n-3 polyunsaturated fatty acids ( PUFAs) (18 : 2n-6; 20 : 3n-6; 20 : 4n-6; 20 : 5n-3; 22 : 4n-6; 22 : 6n-3). Changes in leukocyte lipidome contribute to development of structural and functional abnormalities of the cells and to the synthesis of oxylipins. This is confirmed by increased number of cells with reduced mitochondrial membrane potential and increased level of proinflammatory mediators, such as thromboxane B2 and leukotriene B4. Conclusion. Structural abnormalities of immune cell membrane should be considered as the primary pathological pathway to general dysfunction of the immune system and the basic mechanism of development of respiratory comorbidity