[Changes in free radicals and possibility of their correction in patients with bronchial asthma]

Abstract

The controversy of data about the role of free radicals in the pathogenesis of bronchial asthma (BA) and lack of clear recommendations for the use of medicaments with antioxidant characteristics in the treatment of patients with BA has challenged us to undertake this study. The aim was to explain characteristics of generation of active forms of oxygen (AFO) by leukocytes, peroxide lipid oxidation (PLO) and antiperoxide plasma activities (APA) in patients with BA, evaluation of their pathogenetic importance and justified use of antioxidants in the complex therapy of BA. For this purpose, 92 patients with BA and 45 healthy volunteers were studied. Generation of AFO by blood leukocytes were examined by the method of luminol-dependent chemiluminiscence (CL). Basal and stimulated HL parameters have been measured. The intensity of PLO was determined according to the contents of malondialdehyde (MDA) in plasma. The APA was determined according to its resistance to the injection of free radicals oxidation of hydrogen peroxide. In patients with acute BA compared with healthy volunteers, both CL parameters were increased. In the same time the contents of plasma MDA and relationship of induced and spontaneous plasma CL were increased which suggested the decreased APA. In remission, both CL parameters of AFK generation by leukocytes and the contents of plasma MDA were decreased approximating the normal, but it was never reached. The direct proportional dependence of the degree of impairment and severity of the BA course and the intensity of free radical process were discovered as well as the reversed proportional dependence among the degree of impairment and severity of BA and plasma APA. However, the least parameters of AFK generation by leukocytes were obtained in patients with asthmatic state. In patients with steroid-dependent bronchial asthma the free radical process is more intensive, the plasma APA being lower than in patients with steroid-non-dependent bronchial asthma. Regarding the free radical process the most responsive was aspirin asthma, the mildest exercise-induced asthma. In patients with steroid-non-dependent BA and in patients with steroid-dependent BA who together with the traditional therapy received also antioxidants (aevit and glutamic acid), the decreased CL parameters of leukocyte AFK generation and the decreased contents of MDA were more manifested than in patients not taking antioxidants.