MORPHOLOGICAL FEATURES OF OSTEOGENIC CELLS IN YOUNG RATS UNDER CONDITIONS OF CHRONIC HYPERGLYCEMIA

Ponyrko A. A., Boomeister V. I., Dmitruk S. N., Teslyk T. P

MORPHOLOGY

Scentific article

Abstract. The article presents the data of structural and functional analysis of changes in bone tissue in conditions of chronic hyperglycemia. The study was conducted on 72 white laboratory rats. To simulate chronic hyperglycemia, a solution of alloxan dihydrate was used, which was administered after a 10-hour fasting of the animals. The study of long bones was carried out using scanning electron microscopy and the expression of osteopontin and RANKL in the cytoplasm of cells was assessed. It has been proven that significant changes in the microarchitecture of the bones of the skeleton cause disturbances in the functioning of osteoblasts and destructive changes in osteocytes. With an increase in the duration of hyperglycemia, pathological changes only progress and become more pronounced. In our study, we found a pronounced reaction of osteoblasts in young rats on the 30th day of observation in the form of significant hypertrophy of the hEPS, destruction of organelles in the cytoplasm, and swelling of mitochondria. At the same time, a compensatory reaction in the form of hEPS hypertrophy was observed in young rats – starting from the 120th day of observation. A special feature is that for all periods of observation up to 180 days in young rats, osteoblast dysfunction manifested itself in the form of hePS hypertrophy. During the experiment, the increasing death of osteocytes in rats was established during the entire observation period, starting from the 30th day of the experiment. In addition, a change in the shape of the lacunae was found starting from the 60th day of observation. Thus, under conditions of chronic hyperglycemia, starting from the 30th day of observation, there is a violation of the functioning of osteoblasts and destructive changes in osteocytes in the bones of experimental young rats. The results of immunohistochemical studies indicate a decrease in the secretory activity of osteoblasts and dysfunction of osteitis. Disruption of the synthesis of osteopontin and RANKL negatively affects the osteogenesis of inert tissue. As a result of prolonged exposure to hyperglycemia on the bones of the skeleton, inhibition of the work of both osteoblasts and osteocytes is observed.

hyperglycemia, long tubular bones, osteoblasts, osteocytes, osteopontin

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«Bulletin of problems biology and medicine» Issue 2 (160), 2021 year, 231-235 pages, index UDK 616.379-008.64:616.71-091-092.9

10.29254/2077-4214-2021-2-160-231-235