Tag Archives: vitamin D3

Vitamin D(3) auto-/paracrine system in rat brain relating to vitamin D(3) status in experimental type 2 diabetes mellitus

I. Shymanskyi1*, O. Lisakovska1, A. Khomenko1,
L. Yanitska2, M. Veliky1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv, Ukraine;
2Bogomolets National Medical University, Kyiv, Ukraine;
*e-mail: ihorshym@gmail.com

Received: 29 January 2024; Revised: 08 March 2024;
Accepted: 11 March 2024; Available on-line: 30 April 2024

Growing evidence suggests that vitamin D3 (D3, cholecalciferol) deficiency and impaired signaling of the hormonally active form of D3, 1α,25(OH)2D3 (1,25D3), through its cellular receptor (VDR) can be significant risk factors for the development of numerous multifactorial diseases, including diabetes. Our investigation was aimed at researching the D3 status in relation to the state of the D3 auto-/paracrine system in the brain and clarifying the effectiveness of the therapeutic use of D3 as a neuroprotective agent in experimental type 2 diabetes mellitus (T2DM). T2DM was induced in male Wistar rats by a combination of a high fat diet and a low dose of streptozotocin (25 mg/kg BW). Diabetic animals were treated with or without cholecalciferol (1,000 IU/kg BW, 30 days). The content of 25-hydroxyvitamin D3 (25D3) in blood serum and brain tissue was determined by ELISA. Analysis of mRNA expression of CYP24A1 and CYP27B1 genes was performed by RT-PCR. Protein levels of VDR, vitamin D3 binding protein (VDBP), CYP27B1 and CYP24A1 were investigated by Western blotting. A significant T2DM-associated decrease in the content of 25D3 in the blood serum was revealed, which correlated with a reduced content of this metabolite in the brain tissue. Impaired D3 status in animals with T2DM was accompanied by an increase in the levels of mRNA and protein of both 25D3 lα-hydroxylase (CYP27B1) and 1,25-hydroxyvitamin D3-24-hydroxylase (CYP24A1), which, respectively, provide local formation and degradation in the nervous tissue of the hormonally active form of D3 – 1,25D3. At the same time, a significant T2DM-induced down-regulation of the brain content of VDBP was shown. In addition, diabetes caused a slight increase in the protein expression of the VDR, through which the auto-/paracrine effects of 1,25D3 are realized in the brain. We have established a complete or partial corrective effect of cholecalciferol on D3 status, its bioavailability in the CNS and the level of protein expression of CYP27B1 and CYP24A1 in the brain of rats with T2DM. Abnormal D3 status in animals with T2DM was accompanied by compensatory changes in the expression of key components of the auto-/paracrine vitamin D3 system. Cholecalciferol was demonstrated to be partially effective in counteracting the impairments caused by T2DM.

Vitamin D(3) and methylenebisphosphonic acid in the correction of mineral metabolism disorders and bone remodeling associated with glucocorticoid-induced osteoporosis

O. O. Lisakovska1*, I. O. Shymanskyi1, V. M. Vasylevska1,
E. P. Pasichna1, M. M. Veliky1, S. V. Komisarenko2

1Department of Biochemistry of Vitamins and Coenzymes, Palladin Institute of Biochemistry,
National Academy of Sciences of Ukraine, Kyiv;
2Department of Molecular Immunology, Palladin Institute of Biochemistry,
National Academy of Sciences of Ukraine, Kyiv;
*e-mail: o.lisakovskaya@gmail.com

Received: 03 April 2023; Revised: 27 April 2023;
Accepted: 05 June 2023; Available on-line: 20 June 2023

The study was aimed at evaluating therapeutic efficacy of vitamin D3 (VD3, 1000 IU/kg of b.w., 30 days) and sodium salt of methylenebisphosphonic acid (MBPA, 17 mg/kg of b.w., 30 days) monotherapies as well as their effect in combination in preventing mineral metabolism and bone remodeling disturbances associated with glucocorticoid(GC)-induced osteoporosis. Osteoporosis in rats was induced by long-term (30 days) administration of the synthetic glucocorticoid prednisolone (5 mg/kg of b.w.). Calcium and inorganic phosphate levels, the activity of alkaline phosphatase (ALP) in serum, bone tissue and bone marrow were determined spectrophotometrically. The protein levels of VD3 receptor (VDR), receptor activator of nuclear factor kappa-B (RANK), its ligand (RANKL), and osteoprotegerin (OPG) in bone tissue were determined by Western blotting. Serum 25-hydroxyvitamin D3 (25OHD3) content was assayed by ELISA. It was shown that prednisolone caused the development of hypocalcemia and hypophosphatemia, increased the alkaline phosphatase activity in the blood serum, while downregulating its activity in bone tissue and bone marrow. GC-induced osteoporosis was accompanied by a profound deficiency of VD3 and a decrease in the content of VDR. Evaluation of the NF-κB-associated cytokine axis RANK/RANKL/OPG, which regulates the balance of osteoblasts/osteoclasts, showed a simultaneous decrease in the RANK content and OPG/RANKL ratio. Vitamin D3 restored mineral metabolism and 25OHD3 level that led to the normalization of VDR-mediated signaling­ and RANK/RANKL/OPG functions in bone tissue. It has been shown that the administration of MBPA had a corrective effect on the content of mineral components in the blood serum and bone tissue, as well as on the activity­ of alkaline phosphatase only in combination with vitamin D3, indicating a low efficiency of bisphosphonate monotherapy in GC-induced vitamin D3 deficiency and osteoporosis.

Vitamin D(3) regulates hepatic VEGF-A and apelin expression in experimental type 1 diabetes

D. O. Labudzynskyi1*, I. O. Shymanskyi1, O. O. Lisakovska1,
A. O. Mazanova1, L. V. Natrus2, M. M. Veliky1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Bogomolets National Medical University, Kyiv, Ukraine;
*e-mail: konsument3@gmail.com

Received: 09 July 2019; Accepted: 15 May 2020

The deficiency of vitamin D is associated with the risk of various chronic diseases, including diabetes mellitus and its complications. Given the strong genomic action of vitamin D hormone-active form, its deficiency can lead to dysfunction of cytokine signaling pathways, including those dependent on vascular endothelial growth factors (VEGFs) and apelin. The present study was carried out to define the link between VEGF-A and apelin expression in liver, hepatocytes viability and vitamin D status at experimental type 1 diabetes in mice. We established that chronic hyperglycemia at streptozotocin-induced diabetes was accompanied by a 2.2-fold decrease in 25OHD content in the serum and increased hepatocytes apoptosis and necrosis. Vitamin D deficiency correlated with increased apelin and VEGF-A (8- and 1.6-fold respectively) expression. Almost complete restoration of circulatory 25OHD content in serum was achieved at vitamin D3 treatment (800 IU/kg, per os, for 2 months) followed by reduced apelin and VEGF-A expression in liver and the decline of hepatocytes apoptosis. We conclude that vitamin D3 can be involved in cell survival, angiogenesis and fibrogenesis by modulating  VEGF-A and apelin dependent regulatory systems in diabetic liver.

Liver cytochrome P450-hydroxylation system of tumor-bearing rats under the influence of ω-3 polyunsaturated fatty acids and vitamin D(3)

I. O. Shymanskyi1, O. V. Ketsa2, M. M. Marchenko2, М. М. Veliky1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: ihorshym@gmail.com;
2Fedkovich Chernovtsy National University, Chernovtsy

The study was performed to investigate the effects of the separate and combined action of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) and vitamin D3 on the activity of the components of the oxygenase and reductase chains of the monooxygenase system (MOS) in the microsomal fraction isolated from the liver of rats with transplanted Guerin carcinoma. In the liver of the tumor-bearing rats during the intensive growth of the tumor (14 days, which corresponds to the logarithmic phase of tumor growth), the functional activity of the MOS was weakened. N-demethylase, p-hydroxylase and NADPH-cytochrome P450 reductase activity decreased, with the simultaneous enhancement of cytochrome P450 inactivation rate due to its transformation into an inactive form, cytochrome P420. In turn, we found an increase in the functional activity of the reductase chain of MOS, which components are known to transfer electrons from the reduced NADH through NADH-cytochrome b5-reductase and cytochrome b5 to cytochrome P450. In particular, the activity of NADH-cytochrome b5-reductase and the rate of reduction of cytochrome b5 were elevated with a simultaneous decrease in its content. Both ω-3 PUFAs and vitamin D3 administration to tumor-bearing rats for 42 days (28 days of preliminary administration and 14 days of tumor growth) significantly normalized the oxygenase activity of MOS, increasing NADPH-cytochrome P450-reductase, N-demethylase and p-hydroxylase activity of cytochrome P450 and blocking cytochrome P450 inactivation rate in the microsomal fraction of the liver. Administration of ω-3 PUFAs in combination with vitamin D3 led to the synergy. Changes in the activity of the components of the reductase chain of MOS in liver of tumor-bearing rats were observed mainly after ω-3 PUFAs supplementation. The content of cytochrome b5 increased and the rate of its reduction was significantly diminished. In the absence of a pronounced individual effect of vitamin D3 on the reductase chain of MOS, its co-administration with ω-3 PUFA was also found to be ineffective.

Prednisolone and vitamin D(3) modulate oxidative metabolism and cell death pathways in blood and bone marrow mononuclear cells

I. O. Shymanskyy, O. O. Lisakovska, A. O. Mazanova,
D. O. Labudzynskyi, A. V. Khomenko, M. M. Veliky

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: ishymansk@inbox.ru

The study was designed to evaluate reactive oxygen species (ROS)/nitric oxide (NO) formation and apoptotic/necrotic cell death elicited by prednisolone in peripheral blood and bone marrow mononuclear cells and to define the efficacy of vitamin D3 to counter glucocorticoid (GC)-induced changes. It was shown that prednisolone (5 mg per kg of female Wistar rat’s body weight for 30 days) evoked ROS and NO overproduction by blood mononuclear cells (monocytes and lymphocytes) that correlated with increased cell apoptosis and necrosis. In contrast, prednisolone did not affect ROS/NO levels in bone marrow mononuclear cells that corresponded to lower level of cell death than in the control. Alterations of prooxidant processes revealed in mononuclear cells and associated with GC action were accompanied by vitamin D3 deficiency in animals, which was assessed by the decreased level of blood serum 25-hydroxivitamin D3 (25OHD3). Vitamin D3 administration (100 IU per rat daily for 30 days, concurrently with prednisolone administration) completely restored 25OHD3 content to the control values and significantly reversed ROS and NO formation in blood mononuclear cells, thus leading to decreased apoptosis. In bone marrow, vitamin D3 activated ROS/NO production and protein nitration that may play a role in prevention of prednisolone-elicited increase in bone resorption. We conclude that vitamin D3 shows a profound protection against GC-associated cellular damage through regulating intracellular ROS/NO formation and cell death pathways.

Immunomodulatory effects of vitamin D(3) and bisphosphonates in nutritional osteoporosis in rats

V. M. Riasniy, L. I. Apukhovska, N. N. Veliky, I. O. Shymanskyy,
D. O. Labudzynskyi, S. V. Komisarenko

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: Riasniy@ukr.net

The aim of this study was to determine the effectiveness of separate and combined administration of vitamin D3 and different forms of bis­phosphonate (disodium salt of methylenbisphosphonic acid dihydrate and alendronate) on the function of immune cells in rats with nutritional osteoporosis. It was shown that D-hypovitaminosis leads to reduced 25OHD3, which is a biomarker for vitamin D3 and disturbances of metabolic processes in bone tissue that correlated with osteoporosis manifestation. Immunologic disorders related to nutritional osteoporosis were accompanied by the decrease in phagocytic activity of granulocytes and impaired ability to produce bactericidal oxidants. Inhibition of B-cell immunity also occurred in pathol­gy. Thus, the present study revealed more pronounced immunomodulatory effects of vitamin D3 on phagocytic immunity, whereas bisphosphonates were effective in improving the humoral immune protection.

Use of vitamins for correction of the functional state of cytochrome P450 systems at experimental allergic encephalomyelitis

E. P. Pasichna1, G. V. Donchenko1, A. P. Burlaka2, V. S. Nedzvetskiy3,
E. P. Sidorik2, I. I.Ganusevich2, N. V. Delemenchuk1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, National Academy of Sciences of Ukraine, Kyiv;
3Honchar National University, Dnipropetrovsk, Ukraine;
e-mail: ellapasich@gmail.com

It is known that inflammatory cytokines, which level is significantly increased in the pathogenesis of multiple sclerosis (MS), as well as interferon-β, which is used to treat autoimmune diseases, can inhibit cytochrome P450-dependent processes of detoxification and biotransformation. The uncontrolled decrease of the activity of these processes may have a negative affect on the state of patients, so it is urgent to study the functional state of the cytochrome P450 system and to develop effective means for its regulation in these conditions. The effect of vitamin D3 and efficiency of its composition with vitamins B1, B2, B6, PP, E, α-lipoic, α-linolenoic acid and mineral substances (Mg, Zn, Se) in prevention of a functional state changes of cytochrome P450- and b5-dependent systems of the rat brain and liver endoplasmic reticulum at EAE are investigated. It has been shown that the essential decrease of the level of these cytochromes is observed both in the brain and liver. In addition the level of activity of NADH-and NADPH-oxidoreductases, which are part of microsomal electron transport chain components and coupled with monooxigenases, was reduced. These changes confirm the disturbances of a redox state and functional activity of detoxication and biotransformation systems in the studied animal tissues. Supplement of vitamin D3 as well as the composition of biologically active substances, which we developed earlier, effectively eliminated the decrease of the level of cytochromes and activities of NADH-oxidoreductase in immunised rat tissues. Normalization of these disturbances can be explained by antioxidant and membrane-stabilizing properties of applied substances, and also by the ability to reduce the activity of inflammatory reactions by regulation of the level of inflammatory cytokines in rat organism at EAE. Thus the studied vitamin-mineral composition appeared to be more effective to normalize the found disturbances and it can be useful for prevention of exacerbations and for improvement of a status of patients with multiple sclerosis and other diseases, which are accompanied with hyperactivation of immune system.

Cholecalciferol hydroxylation in rat hepatocytes under the influence of prednisolone

A. V. Khomenko

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: annavic@ukr.net

Glucocorticoid therapy is accompanied by development of processes typical of steroid osteoporosis. Indirect effects of glucocorticoids on the bone tissue are due to changes in mineral metabolism, which is regulated by vitamin D3. In this connection, we studied the influence of prednisolone on cholecalciferol metabolism. The study has shown that prednisolone action causes impairment of cholecalciferol metabolism in hepatocytes due to inhibiting vitamin D3 25-hydroxylase activity. Microsomal (CYP2R1) and mitochondrial (CYP27A1­) isoenzymes of vitamin D3 25-hydroxylase were found to function at different concentrations of the substrate. The relative protein contents of the isoenzymes greatly differed in the liver with the prevalence of CYP27A1 over CYP2R1. Prednisolone administration resulted in the lowering of both mitochondrial and microsomal isoenzymes of vitamin D3 25-hydroxylase. The inhibition of vitamin D3 25-hydroxylating system in hepatocytes contributed to a significant reduction in blood serum 25OHD3.

Vitamin D(3) contribution to the regulation of oxidative metabolism in the liver of diabetic mice

D. O. Labudzynskyi, O. V. Zaitseva, N. V. Latyshko,
O. O. Gudkova, M. M. Veliky

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: konsumemt3@gmail.com

This work is devoted to the study of the features of oxidative metabolism of hepatocytes in diabetic mice and those under the vitamin D3 action. We found out that a 2.5-fold decrease of 25OHD3 content in the serum was caused by chronic hyperglycemia in diabetes. Intensification of the reactive oxygen species (ROS) and nitrogen monoxide (NO) production, protein oxidative modifications (detected by the contents of carbonyl groups and 3-nitrotyrosine), accumulation of diene conjugates and TBA-reactive products of lipid peroxidation, and the decreased level of free SH-groups of low molecular weight compounds in the liver were accompanied by development of vitamin D3 deficient state. It was shown that there was a decrease in the key antioxidant enzymes activity (catalase, SOD), while the activity of prooxidant enzymes NAD(P)H:quinone oxidoreductase, xanthine oxidase and NAD(P)H oxidase was increased. The identified oxidative metabolism lesions caused the elevation of the hepatocytes necrotic death that was tested for the ability of their nuclei to accumulate propidium iodide. Prolonged vitamin D3 administration (during 2 months) at a dose of 20 IU to diabetic mice helps to reduce the ROS formation and biomacromolecules oxidative damage, normalizes the antioxidant system state in the liver and increases survival of hepatocytes. The results suggest that vitamin D3 is a key player in the regulation of the oxidative metabolism in diabetes.

Vitamin D(3) availability and functional activity of peripheral blood phagocytes in experimental type 1 diabetes

D. О. Labudzynskyi, І. О. Shymanskyy, V. М. Riasnyi, М. М. Veliky

Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
e-mail: konsument3@gmail.com

The study was devoted to identifying the relation between vitamin D3 availability (assessed by the level of circulatory 25OHD3), content of vitamin D3 25-hydroxylase isozymes CYP27A1 and CYP2R1 in hepatic tissue and functional activity of peripheral blood phagocytes in mice with experimental type 1 diabetes. It has been shown that diabetes is accompanied by the development of vitamin D3-deficiency which is characterized by decreased 25OHD3 content in blood serum and determined by changes in tissue expression of the major isoforms of vitamin D3 25-hydroxylase. The level of hepatic CYP27A1 was revealed to be markedly reduced with a concurrent significant augmentation of CYP2R1. Cholecalciferol administration resulted in normalization of tissue levels of both isoforms of vitamin D3 25-hydroxylase and blood serum 25OHD3 content. Diabetes-associated vitamin D3 deficiency correlated with a decrease in phagocytic activity of granulocytes and monocytes, and their ability to produce antibacterial biooxidants such as reactive oxygen and nitrogen forms. Vitamin D3 efficacy to attenuate these abnormalities of immune function was established, indicating an important immunoregulatory role of cholecalciferol in the phagocytic mechanism of antigens elimination implemented by granulocytes and monocytes.