Matrix metalloproteinase-9 in age-related transformation of bronchopulmonary dysplasia in children

Background. Currently, it is important to study the immunopathological mechanisms underlying the development of bronchopulmonary dysplasia, which, as is commonly known, are accompanied by active inflammation, leading to structural changes in the tissues of the lungs and bronchi. At the same time, despite the leading etiopathogenetic significance of matrix metalloproteinase-9 (MMP-9), there are isolated articles in the literature highlighting the dynamics of enzyme levels in the context of clinical course and disease outcomes. The data obtained will be useful for understanding the intimate mechanisms of the development of pathology, including bronchopulmonary dysplasia (BPD) in children and be the basis of personalized therapy. Objective. Determination of the MMP-9 levels depending on the severity, phase of the disease and BPD outcomes in children. Methods. According to the study design, 146 children with BPD were examined at the stage of revision of the diagnosis due to age-related transformation. The complex of examination included general clinical and instrumental research methods in accordance with the standard of medical care. The severity and form of BPD in patients were determined according to the working classification of clinical forms of bronchopulmonary diseases in children [2]. The determination of MMP-9 in blood serum was carried out by the method of enzyme-linked immunosorbent assay using the ELISA Kit for MMP-9 (Cloud-Clone Corp., USA). With a normal distribution of the variables, statistical analysis of the results was carried out using the methods of parametric statistics. Results. Follow-up of children over 3 years of age did not reveal statistically significant differences in the studied enzyme levels compared to the children in the control group, despite the traced trend of an increase in average level with increasing severity. At the same time, during the period of exacerbation, a significant increase in the MMP-9 level was observed, which indicates the activation of inflammation with the involvement of the main gelatinase B producer cells. Summing up the data reflecting the structure of indicators depending on the outcomes of BPD, there was no significant increase in the MMP-9 level in patients with chronic bronchopulmonary pathology and recovered children relative to each other and the control group. Conclusion. According to the study, by the time the diagnosis was revised, children with a new form of BPD had reference serum MMP-9 values, which may be associated with the completion of the processes of fibrosis of the lung tissue on the one hand and the favorable effect of surfactant administration in the neonatal period, on the other.

bronchopulmonary dysplasia, disease outcomes, children, MMP-9, inflammation