Tag Archives: type 1 diabetes mellitus
The impact of vitamin D(3) on bone remodeling in different types of experimental pathology
A. O. Mazanova*, O. O. Makarova, A. V. Khomenko, V. M. Vasylevska,
O. Yu. Lototska, I. O. Shymanskyi, M. M. Veliky
Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
*e-mail: ann.mazanova@gmail.com
Received: 17 June 2022; Revised: 28 July 2022;
Accepted: 29 September 2022; Available on-line: 06 October 2022
Osteoporosis is a progressive systemic skeletal disease characterized by a decrease in bone density, impairment of its microarchitectonics, and an increased risk of fractures that occur under minimal or no mechanical stress. One of the main causes of osteoporosis is vitamin D deficiency, which leads to disruption of normal bone remodeling. The aim of our study was to analyze the features of the process of bone tissue remodeling by measuring the key biochemical markers of bone formation/resorption in primary and secondary osteoporosis, as well as to investigate the potential corrective effect of vitamin D3 supplementation. The work was conducted on rats with different osteoporosis models: alimentary, dysfunctional and secondary osteoporosis associated with diabetes mellitus. We used ELISA to measure 25(OH)D content in blood serum. Blood serum and bone tissue calcium, and alkaline phosphatase activity were determined with bioassay kits. The content of inorganic phosphate in blood serum and ash was assayed by the Dyce method. It was shown that all the studied pathological conditions were accompanied by vitamin D deficiency, which led to impaired absorption of calcium in the intestine and reabsorption of inorganic phosphates by the kidneys, reducing, as a result, their concentration in the blood serum. Hypocalcemia and hypophosphatemia contributed to the disruption of normal bone remodeling, excessive activation of alkaline phosphatase, and a decrease in the content of calcium and phosphate in bone tissue. Thus, sufficient vitamin D bioavailability was confirmed to be critical for effective bone remodeling in primary and secondary osteoporosis.
Activation of the phosphatidylinositol-3′-kinase pathway with lectin-induced signal through sialo-containing glycoproteins of leukocyte membranes under type 1 diabetes mellitus
N. Sybirna1, М. Zdioruk1, І. Brodyak1, M. Bars’ka2, О. Vovk2
1Ivan Franko National University of Lviv, Ukraine;
2Institute of Cell Biology, National of Academy of Sciences of Ukraine, Lviv;
e-mail: sybirna_natalia@yahoo.com
The influence of wortmannin and sialospecific lectins on the translocation of p85α regulatory subunit of phosphatidylinositol-3′-kinase (PI-3′-kinase) between membrane and cytosolic fractions of the mononuclear and polymorphonuclear leukocytes in healthy donors and patients with type 1 diabetes mellitus (DM) was investigated. It was found out that under type 1 DM PI-3′-kinase takes active part in the transduction of lectin-induced signal through membrane glycoprotein receptors that contain terminal sialic acids linked to subterminal carbohydrate residues with (α2→6) glycosidic bond.