The microchamber wound coatings effect on the microcirculatory reactions dynamics in the full-thickness skin defect area in white rats

Abstract

Introduction. The widespread occurence of acute and chronic wounds in Russia and abroad determines the great relevance of improving the treatment technologies. The micro- and nanostructuring synthetic polymers (i. e., polylactide) open the new possibilities for creating biodegradable coatings having both scientigfic and applied interest.The aim of present study was to investigate how microchamber polylactide biodegradable coatings affects microcirculatory changes in the area of a full-thickness experimental skin defect in white rats.Materials and methods. The study was conducted on 40 white outbred rats, divided into 3 groups: control (CON, n=10), comparative (ESD) – 15 animals with a full-thickness experimental skin defect) and experimental (MPC) – 15 rats treated by a microchamber polylactide biodegradable coating on full-thickness experimental skin defect. Polylactide (polylactic acid) wound coatings in the form of microchambers arrays were fabricated based on a micron well pattern. On the 7th and 14th days of the experiment, in animals of the ESD and MPC groups, the area of the wound defect was measured and the skin microcirculation of the experimental wound edges was assessed by laser Doppler flowmetry (LDF).Results. On the 7th and 14th days after the experimental wound defect formation in the rats interscapular region an increase of the wound edges skin perfusion by 26.9–27.8 % was observed accompanied by an active and passive mechanisms role redistribution in microcirculatory modulation with increase of perfusion fluctuation in the myogenic, respiratory and cardiac ranges. Using the a polylactide coating for the wound defect closure accelerated the process of epithelialization mainly on the first week of the experiment and reduced the severity of the perfusion increase in the edges of the experimental wound in the first week and completely recovered normal perfusion level in the second week of the experiment. Perfusion decrease of the experimental skin wound edges under the influence of polylactide coating in rats was accompanied by decrease in the amplitude of myogenic oscillations on the 7th day of the experiment by 20 %, and decrease the amplitude of respiratory oscillations on the 14th day by 19.7 % compared to ESD group.Conclusion. The developed polylactide coatings reduce the severity of inflammatory changes in the microcirculation of the experimental wound edges. This redusing combined with the acceleration of wound epithelialization suggests that this type of dressing material is high biocompatible.