title: The Impact of Vitamin D3 Supplementation on Mechanisms of Cell Calcium Signaling in Chronic Kidney Disease.
abstract: Intracellular calcium concentration in peripheral blood mononuclear cells (PBMCs) of patients with chronic kidney disease (CKD) is significantly increased, and the regulatory mechanisms maintaining cellular calcium homeostasis are impaired. The purpose of this study was to examine the effect of vitamin D3 on predominant regulatory mechanisms of cell calcium homeostasis. The study involved 16 CKD stages 2-3 patients with vitamin D deficiency treated with cholecalciferol 7000-14000 IU/week for 6 months. The regulatory mechanisms of calcium signaling were studied in PBMCs and red blood cells. After vitamin D3 supplementation, serum concentration of 25(OH)D3 increased (P < 0.001) and [Ca(2+)]i decreased (P < 0.001). The differences in [Ca(2+)]i were inversely related to differences in 25(OH)D3 concentration (P < 0.01). Vitamin D3 supplementation decreased the calcium entry through calcium release activated calcium (CRAC) channels and purinergic P2X7 channels. The function of P2X7 receptors was changed in comparison with their baseline status, and the expression of these receptors was reduced. There was no effect of vitamin D3 on P2X7 pores and activity of plasma membrane Ca(2+)-ATPases. Vitamin D3 supplementation had a beneficial effect on [Ca(2+)]i decreasing calcium entry via CRAC and P2X7 channels and reducing P2X7 receptors expression.
authors.affiliation: Department of Clinical and Experimental Pharmacology, Faculty of Medicine, Slovak Medical University, 833 03 Bratislava, Slovakia.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Lajdova
authors.affiliation: Department of Clinical and Experimental Pharmacology, Faculty of Medicine, Slovak Medical University, 833 03 Bratislava, Slovakia.
authors.forename: Viera
authors.initials: V
authors.lastname: Spustova
authors.affiliation: Department of Clinical and Experimental Pharmacology, Faculty of Medicine, Slovak Medical University, 833 03 Bratislava, Slovakia.
authors.forename: Adrian
authors.initials: A
authors.lastname: Oksa
authors.affiliation: Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, 833 03 Bratislava, Slovakia.
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Kaderjakova
authors.affiliation: Department of Biophotonics, International Laser Centre, 833 03 Bratislava, Slovakia.
authors.forename: Dusan
authors.initials: D
authors.lastname: Chorvat
authors.affiliation: Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, 833 03 Bratislava, Slovakia.
authors.forename: Marcela
authors.initials: M
authors.lastname: Morvova
authors.affiliation: Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, 833 03 Bratislava, Slovakia.
authors.forename: Libusa
authors.initials: L
authors.lastname: Sikurova
authors.affiliation: Department of Biophotonics, International Laser Centre, 833 03 Bratislava, Slovakia.
authors.forename: Alzbeta
authors.initials: A
authors.lastname: Marcek Chorvatova
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects / Q000235:genetics; D002136:Calcium, Dietary / Q000008:administration & dosage; D002762:Cholecalciferol / Q000008:administration & dosage* / Q000378:metabolism; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D058486:Receptors, Purinergic P2X7 / Q000096:biosynthesis* / Q000235:genetics; D051436:Renal Insufficiency, Chronic / Q000178:diet therapy / Q000235:genetics* / Q000473:pathology; D014808:Vitamin D Deficiency / Q000178:diet therapy / Q000235:genetics* / Q000473:pathology
chemical_list: D002136:Calcium, Dietary; D058486:Receptors, Purinergic P2X7; D002762:Cholecalciferol; D002118:Calcium