Molecular and cellular mechanisms of vitamin D3 protection in experimental prednisolone-induced osteoporosis
Background. Osteoporosis is the most common side effect of glucocorticoid (GC) therapy. Vitamin D is known to play a crucial role in bone remodeling, but the precise molecular mechanisms of its action on GC-induced impairments of cytokine systems, in particular RANK (receptor activator of nuclear factor kappa-B)/RANKL (RANK ligand)/OPG (osteoprotegerin), are still controversial. Thus, the purpose of the study was to evaluate GC-induced changes in the RANK/RANKL/OPG system and osteocalcin synthesis in rat bone depending on vitamin D bioavailability and vitamin D receptor (VDR) expression. Materials and methods. Female Wistar rats received prednisolone (5 mg/kg b.w.) with or without 100 IU of vitamin D3 (for 30 days). The levels of VDR, osteocalcin, RANK, RANKL and OPG in bone tissue were determined by western blotting. Blood serum 25OHD was assayed by enzyme-linked immunosorbent assay. The levels of Ca2+, Pi, activity of alkaline phosphatase (AP) and its bone isoenzyme were determined using spectrophotometry. Results. Prednisolone significantly lowered 25OHD content in the blood serum and VDR level in bone tissue that has been accompanied by an elevation of the AP bone isoenzyme activity in the blood serum, hypocalcemia and hypophosphatemia. A significant decrease in the expression of osteocalcin, a well-known marker of bone formation, was also observed. GC-induced disturbances in vitamin D status led to a reduction of the RANK and OPG level, while RANKL level was unaffected. Vitamin D3 administration restored 25OHD and VDR levels that resulted in amelioration of GC-induced changes in bone tissue and normalization of mineral metabolism through elevation of RANK, OPG and osteocalcin levels. Conclusions. Prednisolone-induced imbalance in the RANK/RANKL/OPG and osteocalcin systems is related to the reduction of vitamin D bioavailability and impairments in VDR signaling. Thus, normalization of vitamin D bioavailability might be perspective in reducing the negative effects of GC on bone homeostasis.
Full Text:PDF (Українська)
Hartmann K, Koenen M, Schauer S, et al. Molecular actions of glucocorticoids in cartilage and bone during health, disease, and steroid therapy. Physiol Rev. 2016 Apr;96(2):409-47. doi: 10.1152/physrev.00011.2015.
Canalis E. Clinical review 83: Mechanisms of glucocorticoid action in bone: implications to glucocorticoid-induced osteoporosis. J Clin Endocrinol Metab. 1996 Oct;81(10):3441-7. doi: 10.1210/jcem.81.10.8855781.
Brändström H, Bjorkman T, Ljunggren O. Regulation of osteoprotegerin secretion from primary cultures of human bone marrow stromal cells. Biochem Biophys Res Commun. 2001 Jan 26;280(3):831-5. doi: 10.1006/bbrc.2000.4223.
Shi C, Qi J, Huang P, et al. MicroRNA-17/20a inhibits glucocorticoid-induced osteoclast differentiation and function through targeting RANKL expression in osteoblast cells. Bone. 2014 Nov;68:67-75. doi: 10.1016/j.bone.2014.08.004.
Kinoshita Y, Masuoka K, Miyakoshi S, Taniguchi S, Takeuchi Y. Vitamin D insufficiency underlies unexpected hypocalcemia following high dose glucocorticoid therapy. Bone. 2008 Jan;42(1):226-8. doi: 10.1016/j.bone.2007.09.042.
Komissarenko YuI, Bobryk MI. Autoimmune Disorders in Endocrine Pathology. A New Look on the Diagnosis and Management. According to the Materials of 18th European Congress of Endocrinology (Munich, May 2016). Mezhdunarodnyi Endokrinologicheskii Zhurnal. 2016;76(4):41-4. doi: 10.22141/2224-0722.214.171.1246.77797. (in Russian).
Montecino MA, Lian JB, Stein JL, Stein JS, van Wijnen AJ, Cruzat F. Biological and molecular effect of vitamin D on bone. In: Holick MF. Vitamin D. Physiology, molecular biology, and clinical applications. Totowa, USA: Humana Press; 2010. 1160 p.
Caprio M, Infante M, Calanchini M, Mammi C, Fabbri A. Vitamin D: not just the bone. Evidence for beneficial pleiotropic extraskeletal effects. Eat Weight Disord. 2017 Mar;22(1):27-41. doi: 10.1007/s40519-016-0312-6.
Li H, Xie H, Fu M, et al. 25-hydroxyvitamin D3 ameliorates periodontitis by modulating the expression of inflammation-associated factors in diabetic mice. Steroids. 2013 Feb;78(2):115-20. doi: 10.1016/j.steroids.2012.10.015.
Lapach SN, Chubenko AV, Babich PN. Statisticheskie metody v mediko-biologicheskikh issledovaniiakh s ispol'zovaniem Excel [Statistical methods in biomedical studies using Excel]. Kiev: Morion; 2000. 320 p. (in Russian).
Povorozniuk VV, Dedukh NV, Grigor'eva NV, Gopkalova IV. Eksperimental'nyi osteoporoz [Experimental osteoporosis]. Kiev: Ekspress; 2012. 228 p. (in Russian).
Matsubara R, Kukita T, Ichigi Y, et al. Characterization and identification of subpopulations of mononuclear preosteoclasts induced by TNF-α in combination with TGF-β in rats. PLoS One. 2012; 7(10): e47930. doi: 10.1371/journal.pone.0047930.
Weinstein RS, Jilka RL, Parfitt AM, Manolagas SC. Inhibition of osteoblastogenesis and promotion of apoptosis of osteoblasts and osteocytes by glucocorticoids. Potential mechanism of their deleterious effects on bone. J Clin Invest. 1998 Jul 15;102(2):274-82. doi: 10.1172/JCI2799.
Lisakovska O, Shymanskyy I, Mazanova A, Khomenko A, Veliky M. Vitamin D3 protects against prednisolone-induced liver injury associated with the impairment of the hepatic NF-κB/iNOS/NO pathway. Biochem Cell Biol. 2017 Apr;95(2):213-22. doi: 10.1139/bcb-2016-0070.
- There are currently no refbacks.
Copyright (c) 2017 Bol', Sustavy, Pozvonochnik - Pain, Joints, Spine
This work is licensed under a Creative Commons Attribution 4.0 International License.
© Publishing House Zaslavsky, 1997-2017