S.V. Klychenkov1, A.D. Kruchinina2

1,2 Penza State University (Penza, Russia)

In the periodic literature, there is a large amount of data on the role of various neurotransmitters, neuropeptides and enzymes of their metabolism in the formation of anxiety and chronic stress. It has been established that the brain renin-angiotensin system, to which peptidyl dipeptidase A belongs, plays an important role in the development of anxiety and the body's response to stress. It is also known that pathological stress and anxiety conditions can lead to the development of depression and even damage to the nervous tissue, so the search for new anxiolytic molecules is a promising study field in biology, since it is often easier to prevent a disease than to eliminate it with the help of pharmacotherapy. Recently, a large number of peptides with anxiolytic activity have been isolated from various raw materials of plant and animal origin, including beekeeping products such as royal jelly and drone brood.

The aim of this study is to find the effect of a fraction of peptides weighing up to 5 kDa, obtained from royal jelly, bee honey and drone brood, on the activity of peptidyl dipeptidase A under chronic stress. Male Wistar rats (n = 8) participated in the experiment. Animals were subjected to chronic unpredictable mild stress for 16 days, while simultaneously receiving intranasal aqueous solutions of peptides of royal jelly, drone brood and bee honey at a concentration of 300 µg/kg of body weight. Rats of the control group received 0.9% solution of NaCl. The degree of formation of a chronic anxiety state was determined with the "Elevated plus maze" test: the animals of the control group passed it on the 1st, 5th, 10th and 15th days. On the 17th day, the rats were withdrawn from the experiment, and blood serum, pituitary gland, hypothalamus, striatum, hippocampus, amygdala, quadrigemina, and medulla oblongata were used to study the activity of the enzyme.

It was found that under the influence of peptides of drone brood and royal jelly, the activity of the enzyme decreases in the pituitary gland, hypothalamus, striatum, amygdala, quadrigemina and medulla oblongata and does not change in the blood serum and hippocampus; bee honey peptides do not affect the activity of the enzyme in all parts of the brain and blood serum. Probably, the previously known anxiolytic effect of peptides of bee products is realized due to the influence on the activity of peptidyl dipeptidase A, which is involved in the regulation of anxious behavior.

The results obtained can be interpreted as the initial stages of preclinical studies of a new peptide drug with anxiolytic activity.

Klychenkov S.V., Kruchinina A.D. Effect of bee products peptides on the activity of peptidyl-dipeptidase A in the blood serum and nervous tissue of rats under chronic stress. Technologies of Living Systems. 2023. V. 20. № 2. Р. 73-80. DOI: https://doi.org/ 10.18127/j20700997-202302-08 (In Russian)

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