Metabolic changes in peripheral blood lymphocytes from children with recurrent respiratory infections

Abstract

Objective: to examine activity and correlative relations for peripheral blood lymphocyte NAD (P)-dependent dehydrogenases in young children with recurrent respiratory infections with hypertrophy of the pharyngeal tonsils and bronchial obstructive syndrome.  Methods. 89 children, aged 1–3 years, with recurrent respiratory infections were examined, including 35 children with hypertrophy of pharyngeal tonsils (HPT) and 54 children — with bronchial obstructive syndrome (BOS). Control group contained 20 age-matched healthy children. Activity and relations for peripheral blood lymphocyte for NAD(P)-dependent dehydrogenases were assessed by using bioluminescent method proposed by А.А. Savchenko and L.N. Suntsova (1989).  Results. It was found that children with recurrent respiratory infections displayed altered enzyme status in peripheral blood lymphocytes. In particular, activity ribose-5-phosphate- and NAD(P)-dependent metabolic events as well as substrate flux via the tricarboxylic acid cycle were elevated that was paralleled with decreased lactate dehydrogenase anaerobic reaction, thereby implicating a role for malate-aspartate shunt in the energy turnover, substrate efflux from the tricarboxylic acid cycle into amino acid metabolic pathways as well as activity of glutathione reductase. Moreover, features of altered enzymatic profile in peripheral blood lymphocytes were uncovered, which depended on type of complication related to respiratory infection. In addition, children with hypertrophy of pharyngeal tonsils were featured with increased influx of lipid catabolism products into glycolysis, elevated level of malic enzyme activity and decreased pyruvate production. However, children with bronchial obstructive syndrome were found to have decreased glycerol-3-phosphate dehydrogenase activity resulting in lowered shunting activity of slow reactions in Krebs cycle and increased influx of amino acid metabolism intermediates into the tricarboxylic acid cycle. Reshaping of enzymatic profile in peripheral blood lymphocytes depended on type of complications coupled to respiratory infections (ENT-pathology or BOS syndrome). A correlation analysis revealed features of relationship between parameters of NAD(P)-dependent dehydrogenase activity in peripheral blood lymphocytes found in children with hypertrophy of pharyngeal tonsils and bronchial obstructive syndrome marked by quantity, modality and power of correlative links.  Conclusion. Children with the recurrent respiratory infections require metabolic therapy aimed at restoring intracellular pathology-driven metabolic processes in immune cells.