CYTOKINE-INDUCED CHANGES IN GLUCOSE UPTAKE AND PYRUVATE KINASE ACTIVITY IN ORGANOTYPIC CULTURES

Glucose uptake is regulated by the activity of glucose transporters (GLUT), which are influenced by various factors. The effects of interleukin-2 (IL-2) on glucose uptake remain controversial, while erythropoietin is known for its anti-apoptotic properties and glucose-lowering effects. This study aimed to evaluate the impact of IL-2 and erythropoietin on glucose uptake and pyruvate kinase M2 (PKM2) activity in organotypic cultures of brain, liver, and skeletal muscle. Organotypic cultures were prepared from white laboratory mice and incubated with IL-2 (5000 and 7500 IU/ml), erythropoietin (13, 6.5, and 1.3 IU/ml), or left untreated (control). Among all tissues, liver cultures exhibited the lowest glucose uptake. IL-2 increased glucose uptake in all culture types, while erythropoietin enhanced uptake only in skeletal muscle cultures. PKM2 activity was cytokine- and tissue-dependent: low-dose IL-2 elevated PKM2 activity in liver and skeletal muscle cultures, whereas high-dose erythropoietin reduced PKM2 activity in skeletal muscle. These findings suggest that erythropoietin may activate GLUT4 in skeletal muscle, while IL-2 may act via GLUT1 across all tissue types, possibly involving other mechanisms. The observed increase in PKM2 activity under IL-2 stimulation may indicate a shift toward aerobic metabolism, while erythropoietin-induced decreases in PKM2 activity may reflect a shift toward glycolytic pathway.