The nature of changes in endocrine and immune factors at the initial stage of the formation of chronic wounds

Abstract

Aim. The work aimed to study the nature of changes in endocrine signals (insulin and cortisol) and bioactive molecules that control inflammation and activation of process synthesis (interleukin-2 (IL-2), interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), amino-terminal propeptide of type III procollagen (PIIINP)), at the initial stage of the formation of chronic wounds in the experiment.
 Materials and methods. The study was conducted in 2 groups of Wistar rats. The first group is represented by intact animals. Animals of the second group were modeled chronic wounds. On the 3rd day of the experiment, all animals were euthanized. The concentration of studied bioactive molecules was measured in blood serum by enzyme immunoassay. Selected areas of the wound were subjected to histological examination.
 Results. The levels of cortisol, insulin, VEGF, IL-2, and PIIINP in animals with chronic wounds at the stage of inflammation were significantly higher compared to intact animals. A tendency towards a decrease in the expression of IL-8 was shown. Relationships between the levels of bioactive molecules in animals of different groups were studied. According to the results of studies a correlation between the concentrations of IL-8 and cortisol in rats of the intact group was established. In the group of rats on the 3rd day after wound induction, a positive correlation was noted between the levels of IL-8 and IL-2. Wound defects healed under the scab. Microscopic analysis showed that the histoarchitectonics of tissues in the area of damage on the 3rd day corresponded to the classic manifestations of the process of healing wounds at this stage. The main part of the wound was filled with fibrin strands with a predominantly inflammatory cellular component. In some areas, signs of growth and development of young granulation tissue were noted. In the marginal sections, signs of re-epithelialization of the wound defect were observed.
 Conclusions. Even though in our study, the histoarchitectonics of tissues in the area of damage corresponded to the classical manifestations of the wound healing process at the stage of inflammation, the obtained changes and the relationship between endocrine and immune factors may be harbingers of the formation of the chronic wound in the future.