Effect of tetrapeptides KK1 and KK5 on the immunological parameters of rat spleen during passive smoking

One of the trends in experimental and clinical immunology is the creation of new immunomodulators aimed at correcting various variants of the pathology of the immune system. Of interest are non-toxic, hormone-free and protease-resistant tetrapeptides, homologue of the of adrenocorticotropic hormone fragment (15- 18). There is little data in the literature on the effect of the above immunomodulators on the immunological parameters of the rat spleen on xenobiotic exposure models, which makes research relevant in this aspect. For the first time, the effect of tetrapeptides with laboratory ciphers KK1 and KK5 on the immunological parameters of the spleen of 36 female Wistar rats with passive smoking was evaluated. The experimental rats were fumigated with tobacco smoke for 8 hours daily for 20 days. Synthetic tetrapeptides were administered intranasally at a dose of 40 micrograms per kg/day, starting from the 10th day of the experiment. It was found that the studied tetrapeptides had a unidirectional positive effect on the immunological parameters of the spleen of experimental animals with passive tobacco smoking. This was expressed in a tendency to restore the pool of cells with CD3, CD4, CD8, CD20 markers to the level of the control group, as well as spontaneous and induced cytokine production by splenocytes. The shifts in the parameters of the spleen identified in this work may be based on a number of possible causes. Firstly, passive smoke causes a stress response in rats, which is confirmed by previous studies on a similar model, on an increase in the level of stress hormones in the blood serum of Wistar rats. Secondly, the literature data indicate the activation of lipid peroxidation during smoking. Thirdly, it is known that under the action of tobacco smoke toxicants, the lymphoid cell line suffers the most, since their polyhydrooxidized metabolites accumulate in the bone marrow and lymphoid organs, causing hypoplasia of the central and peripheral organs of immunity. A visible sign of this phenomenon is a decrease in the cellularity in the spleen, which is established in this work. Considering that active and passive smoking causes hypoxia and increases lipid peroxidation, the use of tetrapeptides KK1 and KK5 as agents that improve the body’s adaptation to hypoxia and increase resistance to stress damage is justified. Thus, the tetrapeptides KK1 and KK5 have a positive immunomodulatory effect, reducing the toxic stress effects of passive smoking.