Effect of the KK1 peptide on immunological parameters in passively smoking pregnant rats and their offspring

Abstract

Currently, experimental studies are actively conducted to assess the effects of low-molecular-weight polypeptide mediators on the immune system, in order to design new immunomodulatory drugs. However, the specific effects of individual peptides on the immune system of experimental animals and their offspring remains insufficiently studied, thus requiring relevant research in this aspect. Our study evaluated the effect of the peptide homologue of the of adrenocorticotropic hormone fragment (15-18) (laboratory code, KК1) on immunological parameters of pregnant rats and their offspring using experimental models of passive maternal smoking exposure.
 The immunological parameters were studied in 96 pregnant Wistar rats weighing 200-300 g, exposed to passive tobacco smoking and receiving a synthetic peptide KK1, which is a structural analogue of the ACTH15-18 sequence fragment (Acetyl-(D-Lys)-Lys-Arg-Arg-amide), as well as probable effect on their offspring tested on the 14th day after birth (76 rats). Experimental rats were fumigated with tobacco smoke for 8 hours daily from the 1st to the 20th day of pregnancy. Synthetic peptide KK1 was administered to pregnant rats in the form of an aqueous solution at a dose of 40 mcg / kg / day five times a day for 10 days. Weights of whole body, thymus and spleen were determined in all animals, the number of leukocytes, thymocytes, splenocytes, myelocaryocytes, circulating immune complexes were assessed in accordance with common protocols for experimental laboratory animals. The data were analyzed by MannWhitney U test. The significance level was set at p 0.05.
 Administration of the KK1 peptide to both control and experimental pregnant rats was accompanied by multidirectional changes in the number of cells in lymphoid organs. The positive trend of shifts in immunological parameters when exposed to the peptide KK1 seems to be based on the possible reduction of the consequences of the toxic effect of tobacco smoke due to the anti-inflammatory effect of this drug, as well as its ability to limit the development of free radical reactions. It is shown that the studied peptide contributes to the positive dynamics of multiple immunological parameters in experimental animals subjected to passive smoking. Further studies are required to assess the mechanisms of immunotropic action of the ACTH15-18 peptide homologue.