Abstract
<jats:p>Low- and medium-molecular-weight substances (LMMWS) and oligopeptides (OPs) constitute a pool of heterogeneous molecules formed during metabolic processes. These substances have been found to play a significant role in the development of metabolic shifts in the course of various homeostatic changes. Evidence has been obtained that individual substances in the LMMWS pool participate in the regulation of metabolic pathways. Considering that the metabolic activity of lymphocytes and their capacity for metabolic reprogramming are crucial at all stages of the immune response, determining the intracellular LMMWS pool provides insight into the state of lymphocyte metabolism. The purpose of this research was to study the spectral characteristics of the pool of LMMWS in peripheral blood lymphocytes and to elucidate the nature of the relationship between their quantitative characteristics and intracellular regulators of immunometabolism. Materials and мethods. The lymphocyte fraction of venous blood of people living in the European North of Russia was explored. To evaluate cellular metabolic activity, the content of regulators of glycolysis (HIF-1α) and mitochondrial processes (SIRT3) were determined in the lymphocyte cell lysate using enzyme-linked immunosorbent assay. In lymphocyte supernatants, the optical density of LMMWS in the 224–304 nm wavelength range was measured using a double beam spectrophotometer, after which a spectral curve was plotted and the area under the curve was calculated. OP fraction was measured at a wavelength of 750 nm using the photometric method. Spearman’s rank correlation coefficient was calculated to analyse the relationships. Results. For the first time, the characteristic features of the spectrograms of LMMWS in the supernatants of peripheral blood lymphocytes were recorded and determined. A moderate negative correlation between HIF-1α concentration and the content of LMMWS and OPs in lymphocytes was established. Consistent changes in the immunological reactivity index, HIF-1α/SIRT3 ratio, and LMMWS content were identified. The intracellular content of LMMWS can serve as an informative non-specific criterion, allowing us to promptly assess the metabolic activity of peripheral blood lymphocytes. Changes in this activity are reflected in the spectral curve profile, which facilitates visual monitoring.</jats:p>