Tag Archives: vitamin D3

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.

Correction by vitamin D(3) of disturbed metabolism in patients with diabetes mellitus types 1 and 2

Yu. I. Komisarenko

A. A. Bogomolets National Medical University, Kyiv, Ukraine;
e-mail: julia_komissarenko@hotmail.com

Vitamin D deficiency is an increasingly recognized public health problem of population as a whole and against a background of different chronic diseases. The aim of the study was to determine the status of D-vitamin, mineral, carbohydrate and lipid metabolism in patients with diabetes 1 and 2 types and in the case of vitamin D3 application. The data on the impact of vitamin D3 deficiency on mine­ral, carbohydrate and lipid metabolism, as well as on pancreatic β-cells functional activity in patients with diabetes mellitus types 1 and 2 are presented. Certain reasons that lead to the disruption of vitamin D3 metabolism in patients with diabetes mellitus and the results of vitamin D3 application in clinics are discussed.