Changes in the concentration of melatonin and endogenous proteins regulating carbohydrate and lipid metabolism in rats under conditions of light desynchronosis with pharmacological correction by peptide extracts from the pineal gland and pituitary gl

Purpose of the study. To study the effect of sequential release of peptide extracts (PEE) from the pineal gland and pituitary gland of reindeer (Rangifer tarandus) on endogenous regulatory proteins (hypoxia-inducible factor 1 alpha (HIF1α), peroxisome proliferatoractivated receptor gamma (PPARγ), soluble phosphoenolpyruvate carboxykinase 1 (PEPCK) and melatonin in the blood serum of male rats under conditions of experimental light desynchronosis. Materials and methods. Modeling of light desynchronization was carried out on two-month laboratory white outbred male rats weighing 180 ± 20 g in the number of 144 individuals. The animals were divided by the method of randomization into three main groups: 1st group represented the control, in which the normal lighting regimen was modeled (LED lighting 500 lux day/night 12/12); the 2nd group was kept in the regimen of constant illumination; the third group was kept in a regimen of constant darkness. The formation of light desynchronization was carried out for 30 days. During the first 14 days of the formation of light desynchronosis, the rats were intranasally being administered with the test substances. After 30 days from the beginning of the experiment, the rats were euthanized for the collection of biological material. The blood serum HIF1α, PPARγ, PCK1 and melatonin levels of laboratory animals were analyzed by the enzyme immunoassay method (EIA). Results. The use of PEE in two doses during light deprivation has reduced the concentration of HIF1α in the blood serum, indicating improved oxygen utilization in the tissues of experimental animals. PEE in two doses has caused a sharp increase in the concentration of the transcription factor in blood serum PPARγ, which promotes the initiation of processes regulating the exchange of lipids and carbohydrates in adipose tissue. The application of peptide extracts in two doses has revealed a decrease in the activity of PCK1 under constant illumination. With constant exposure to PEE in doses 100 mg/kg, it promotes an increase in the concentration of melatonin in the blood serum, approximately equal to the level of the control group. Conclusion. The study revealed the chronobiotic effects of PEE on the concentration of regulatory proteins and melatonin in the blood serum of male rats in the conditions of light desynchronization. It should also be noted that these effects differ from the known effects of the delta-sleep inducing peptide, which may be due to a different mechanism of molecular action.