The functionality of redox metabolism is frequently named as an important contributor to the processes of aging and anti-aging. Excessive activation of free radical reactions accompanied by the inability of the antioxidant defense (AOD) mechanisms to control the flow of the reactive oxygen species (ROS) leads to the persistence of oxidative stress, hypoxia, impaired mitochondrial energy function and reduced ATP potential. From a long-term perspective, such changes contribute to the development of chronic diseases and facilitate aging. In turn, preconditioning of a biosystem with small doses of stressful stimuli might cause mobilization of the mechanisms of AOD and control an excessive flow of ROS, which supports optimal functioning of the redox reactions. Those mechanisms are of crucial importance for anti-aging and are also known as a eustress or hormetic response. To ensure continuous support of mild pro-oxidant activity in a metabolic system, close monitoring and timely corrections preventing the development of excessive ROS production are required. The paper introduces the potential of heart rate variability (HRV) as a biomarker of functional and metabolic reserves and a tool to measure stress resilience during aging. The practical approaches to interpretation of HRV are provided based on total power, changes in total power in response to an orthostatic test and activities of all spectral components. It is suggested that the complex of those parameters can reflect the
depth of oxidative stress and may be used to guide lifestyle interventions and promote active longevity.

Актова промова, виголошена на засіданні Вченої ради Львівського національного медичного університету імені Данила Галицького
16 листопада 2022 року з нагоди 238-ї річниці від дня заснування університету

   We studied the influence of maternal hypothyroidism on progeny skin morphogenesis by means of histological, histochemical and lectinhistochemical methods. Hypothyroid conditions in rats were achieved by daily food supplementation with antithyroid drug Mercazolil. The experiment was conducted on 10 control and 10 hypothyroid rats, which delivered 70 and 46 offsprings, respectively. We discovered that maternal hypothyroidism induces the accumulation of mast cells (MCs) in the skin of progeny on the 1st, 10th and 20th postnatal days, with decrease of these cell’s count returning to control level on 40th postnatal day. These results indicate that offsprings developing under conditions of maternal hypothyroidism are a risk group for changes in immune status and the occurrence of allergic reactions. The stratum corneum of epidermis, its lipid barrier as well as pilosebaceous units, in both control and experimental group animals, at the early stages of postnatal ontogenesis are enriched with carbohydrate determinants of αDMan, βDGal, βDGal(1–3)DGalNAc, αLFuc, αDGalNAc, αDGlcNAc, Neu5Ac. Galanthus nivalis agglutinin (GNA) is a selective histochemical marker of MCs, while Lactarius torminosus fungus agglutinin (LTFA) is a selective label of Langerhans cells. Maternal hypothyroidism resulted in reduction of lectin binding with the structural components of progeny skin and its derivatives. We speculate that alterations in glycoconjugate processing and degradation sequences have an impact on the cell signaling, formation of adhesive contacts, cellular proliferation and differentiation. The lectin set we used clearly demonstrated specific labeling of cellular subpopulations, monitoring glycoconjugates processing and degradation under physiological and pathological conditions in all skin components.
Keywords: skin, Mercazolil, hypothyroid rats’ progeny, lectin histochemistry.

UDC 616.716.4-001-089.843-073.7-018

   The issue of finding ways to optimize the course of posttraumatic bone regeneration is very relevant today. The aim of this study was to determine the dynamics of morphological, radiological, and lectin-histochemical characteristics of bone-ceramic regeneration after transplantation of octacalcium phosphate into an experimental defect of the rabbit mandible. The study was conducted on laboratory animals (male rabbits) divided into appropriate groups. Intact animals were used to study the normal structure of the bone tissue of the investigated area of the mandible. The posttraumatic state of the bone tissue in the area of the defect was monitored for 84 days. Morphological examination of the experimental bone defect of the mandible after implantation of osteoplastic material with octacalcium phosphate revealed numerous macroscopic signs of osteoregeneration that correlated with the dynamics of changes in bone surfaces, on radiographs and radiovisiographs and with the lectin-histochemical characteristics of the bone-ceramic regenerate, the peculiarities of the mineral density of the bone tissue of the mandible of the rabbit and the restoration of its quality after implantation of octacalcium phosphate into its cavity were clarified. A fairly high osteoinductive ability of octacalcium phosphate and its effectiveness compared with the control in healing a bone injury under a blood clot were established.
Kеy words: mandible/lower jaw, bone tissue regeneration, osteoplastic materials, morphological study, lectin-histochemistry.