Amiri Gorzoddons A. The mechanism of Dermatotropic Action of Nanocrystalline Cerium Dioxide.

The work is devoted to the study of the biochemical mechanisms of the dermatotropic action of a pharmacological composition consisting of nanocrystalline cerium dioxide at a concentration of 0.05% dissolved in 0.5% carbopol gel on a model of a full-thickness excised plane wound in rats. As a result of the studies, it was found that in phase I of the wound process (inflammation phase) the carbopol gel with nanocrystalline cerium dioxide did not affect the healing of full-thickness excised plane wounds. However, in the II phase (phase of regeneration, formation and maturation of granulation tissue) and III (phase of formation and reorganization of the scar) of the wound process, the composition accelerated the healing of full-thickness plane wounds, which was confirmed by the determination of their area in dynamics. Thus, it was found that on the 6th, 9th and 14th days of the experiment, the area of the wound process decreased by 20.1% (p <0.05), 37.5% (p <0.05) and 34,0% (p <0.05) respectively, compared to the control group of rats in which self-healing occurred. The nature of the wound bed in the animals of the control group during the experiment was significantly worse than in the animals in which the wounds were treated with carbopol gel and nanocrystalline cerium dioxide. In the experimental group, the crust covering the wound on day 6 was thinner and disappeared on day 9 but in the control group the crust was thicker and disappeared only on day 20. Complete wound closure in the control group of animals occurred at 23.0 ± 0.8 days with the formation of a rough scar. In the experimental group of rats in which the wounds were treated with carbopol gel and nanocrystalline cerium dioxide, the healing time decreased by 13.0% (p <0.05) compared to control group and was equal to 20.0 ± 0.5 days. In this case, the healing occurred without the formation of a rough scar. The results obtained showed that the pharmacological composition based on nanocrystalline cerium dioxide exhibits a bactericidal effect on the test cultures of Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa and the fungistatic effect on the test culture of yeast fungi.