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Nowak JI, Olszewska AM, Król O, Żmijewski MA. Protein Disulfide Isomerase Family A Member 3 Knockout Abrogate Effects of Vitamin D on Cellular Respiration and Glycolysis in Squamous Cell Carcinoma. Nutrients 2023; 15:4529. [PMID: 37960182 PMCID: PMC10650882 DOI: 10.3390/nu15214529] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
PDIA3 is an endoplasmic reticulum disulfide isomerase, which is involved in the folding and trafficking of newly synthesized proteins. PDIA3 was also described as an alternative receptor for the active form of vitamin D (1,25(OH)2D3). Here, we investigated an impact of PDIA3 in mitochondrial morphology and bioenergetics in squamous cell carcinoma line A431 treated with 1,25(OH)2D3. It was observed that PDIA3 deletion resulted in changes in the morphology of mitochondria including a decrease in the percentage of mitochondrial section area, maximal diameter, and perimeter. The 1,25(OH)2D3 treatment of A431∆PDIA3 cells partially reversed the effect of PDIA3 deletion increasing aforementioned parameters; meanwhile, in A431WT cells, only an increase in mitochondrial section area was observed. Moreover, PDIA3 knockout affected mitochondrial bioenergetics and modulated STAT3 signaling. Oxygen consumption rate (OCR) was significantly increased, with no visible effect of 1,25(OH)2D3 treatment in A431∆PDIA3 cells. In the case of Extracellular Acidification Rate (ECAR), an increase was observed for glycolysis and glycolytic capacity parameters in the case of non-treated A431WT cells versus A431∆PDIA3 cells. The 1,25(OH)2D3 treatment had no significant effect on glycolytic parameters. Taken together, the presented results suggest that PDIA3 is strongly involved in the regulation of mitochondrial bioenergetics in cancerous cells and modulation of its response to 1,25(OH)2D3, possibly through STAT3.
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Affiliation(s)
- Joanna I. Nowak
- Department of Histology, Medical University of Gdansk, 1a Dębinki, 80-211 Gdansk, Poland; (J.I.N.); (A.M.O.)
| | - Anna M. Olszewska
- Department of Histology, Medical University of Gdansk, 1a Dębinki, 80-211 Gdansk, Poland; (J.I.N.); (A.M.O.)
| | - Oliwia Król
- Department of Biochemistry, Medical University of Gdansk, 80-211 Gdansk, Poland;
| | - Michał A. Żmijewski
- Department of Histology, Medical University of Gdansk, 1a Dębinki, 80-211 Gdansk, Poland; (J.I.N.); (A.M.O.)
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Donati S, Palmini G, Aurilia C, Falsetti I, Marini F, Giusti F, Iantomasi T, Brandi ML. Calcifediol: Mechanisms of Action. Nutrients 2023; 15:4409. [PMID: 37892484 PMCID: PMC10610216 DOI: 10.3390/nu15204409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Due to its essential role in calcium and phosphate homeostasis, the secosteroid hormone calcitriol has received growing attention over the last few years. Calcitriol, like other steroid hormones, may function through both genomic and non-genomic mechanisms. In the traditional function, the interaction between the biologically active form of vitamin D and the vitamin D receptor (VDR) affects the transcription of thousands of genes by binding to repeated sequences present in their promoter region, named vitamin D-responsive elements (VDREs). Non-transcriptional effects, on the other hand, occur quickly and are unaffected by inhibitors of transcription and protein synthesis. Recently, calcifediol, the immediate precursor metabolite of calcitriol, has also been shown to bind to the VDR with weaker affinity than calcitriol, thus exerting gene-regulatory properties. Moreover, calcifediol may also trigger rapid non-genomic responses through its interaction with specific membrane vitamin D receptors. Membrane-associated VDR (mVDR) and protein disulfide isomerase family A member 3 (Pdia3) are the best-studied candidates for mediating these rapid responses to vitamin D metabolites. This paper provides an overview of the calcifediol-related mechanisms of action, which may help to better understand the vitamin D endocrine system and to identify new therapeutic targets that could be important for treating diseases closely associated with vitamin D deficiency.
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Affiliation(s)
- Simone Donati
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Gaia Palmini
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Cinzia Aurilia
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Irene Falsetti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Francesca Marini
- Fondazione Italiana Ricerca Sulle Malattie dell’Osso (FIRMO Onlus), 50129 Florence, Italy;
| | - Francesca Giusti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Teresa Iantomasi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50139 Florence, Italy; (S.D.); (G.P.); (C.A.); (I.F.); (F.G.); (T.I.)
| | - Maria Luisa Brandi
- Fondazione Italiana Ricerca Sulle Malattie dell’Osso (FIRMO Onlus), 50129 Florence, Italy;
- Donatello Bone Clinic, Villa Donatello Hospital, 50019 Sesto Fiorentino, Italy
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Asmussen NC, Alam S, Lin Z, Cohen DJ, Schwartz Z, Boyan BD. 1α,25-Dihydroxyvitamin D 3 Regulates microRNA Packaging in Extracellular Matrix Vesicles and Their Release in the Matrix. Calcif Tissue Int 2023; 112:493-511. [PMID: 36840756 DOI: 10.1007/s00223-023-01067-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 01/30/2023] [Indexed: 02/26/2023]
Abstract
Growth plate chondrocytes are regulated by numerous factors and hormones as they mature during endochondral bone formation, including transforming growth factor beta-1 (TGFb1), bone morphogenetic protein 2 (BMP2), insulin-like growth factor-1 (IFG1), parathyroid hormone and parathyroid hormone related peptide (PTH, PTHrP), and Indian hedgehog (IHH). Chondrocytes in the growth plate's growth zone (GC) produce and export matrix vesicles (MVs) under the regulation of 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3]. 1α,25(OH)2D3 regulates MV enzyme composition genomically and 1α,25(OH)2D3 secreted by the cells acts on the MV membrane nongenomically, destabilizing it and releasing MV enzymes. This study examined the regulatory role 1α,25(OH)2D3 has over production and packaging of microRNA (miRNA) into MVs by GC cells and the release of miRNA by direct action on MVs. Costochondral cartilage GC cells were treated with 1α,25(OH)2D3 and the miRNA in the cells and MVs sequenced. We also treated MVs with 1α,25(OH)2D3 and determined if the miRNA was released. To assess whether MVs can act directly with chondrocytes and if this is regulated by 1α,25(OH)2D3, we stained MVs with a membrane dye and treated GC cells with them. 1α,25(OH)2D3 regulated production and packaging of a unique population of miRNA into MVs compared to the vehicle control population. 1α,25(OH)2D3 treatment of MVs did not release miRNA. Stained MVs were endocytosed by GC cells and this was increased with 1α,25(OH)2D3 treatment. This study adds new regulatory roles for 1α,25(OH)2D3 with respect to packaging and transport of MV miRNAs.
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Affiliation(s)
- Niels C Asmussen
- School of Integrative Life Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Sheikh Alam
- School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA
| | - Zhao Lin
- School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA
| | - David J Cohen
- College of Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Zvi Schwartz
- College of Engineering, Virginia Commonwealth University, Richmond, VA, USA
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Barbara D Boyan
- College of Engineering, Virginia Commonwealth University, Richmond, VA, USA.
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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Liu R, Lu Y, Peng X, Jia J, Ruan Y, Shi S, Shu T, Li T, Jin X, Zhai G, He J, Lou Q, Yin Z. Enhanced insulin activity achieved in VDRa/b ablation zebrafish. Front Endocrinol (Lausanne) 2023; 14:1054665. [PMID: 36864841 PMCID: PMC9972578 DOI: 10.3389/fendo.2023.1054665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/30/2023] [Indexed: 02/16/2023] Open
Abstract
INTRODUCTION 1α,25-dihydroxyvitamin D3 (1α,25[OH]2VD3) is a hormone known for its key roles in calcium absorption and nutrient metabolism. In teleost fishes, 1α,25(OH)2VD3 insufficiency causes impaired glucose metabolism and lipid oxidation. However, the cascade and mechanisms of 1α,25(OH)2VD3 and the vitamin d receptor (VDR) signaling are unclear. RESULTS In this study, two genes (vdra and vdrb) encoding paralogs of VDRs were genetically knocked out in zebrafish. Growth retardation and accumulated visceral adipose tissue have been observed in vdra -/-;vdrb -/- deficient line. In the liver elevated accumulation of triglycerides and suppressed lipid oxidation were detected. Morover significantly elevated 1α,25(OH)2VD3 levels were detected in vdra-/-;vdrb-/- zebrafish due to cyp24a1 transcription repression. Furthermore VDRs ablation Enhanced insulin signaling including elevated insulin/insra trancriptional levels, glycolysis, lipogenesis and promoted AKT/mTOR activity. DISCUSSION In conclusion, our present studies provides a zebrafish model with an elevated 1α,25(OH)2VD3 levels in vivo. The 1α,25(OH)2VD3/VDRs signaling promote lipid oxidation activity. However 1α,25(OH)2VD3 activity of regulation of glucose homeostasis through Insulin/Insr was independent of nuclear VDRs in teleosts.
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Affiliation(s)
- Ruolan Liu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yao Lu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xuyan Peng
- The Laboratory of Ophthalmology and Vision Science, Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zheng Zhou, China
| | - Jingyi Jia
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yonglin Ruan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Shengchi Shi
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Tingting Shu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Tianhui Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xia Jin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Gang Zhai
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jiangyan He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qiyong Lou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- *Correspondence: Qiyong Lou,
| | - Zhan Yin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
- The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
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Fu B, Yang L, Chen Q, Zhang Q, Zhang L, Yu P. Enhanced biosynthesis of physiologically active vitamin D3 by constructing recombinant Escherichia coli BL21 with a multienzyme system. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.12.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Żmijewski MA. Nongenomic Activities of Vitamin D. Nutrients 2022; 14:nu14235104. [PMID: 36501134 PMCID: PMC9737885 DOI: 10.3390/nu14235104] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 12/04/2022] Open
Abstract
Vitamin D shows a variety of pleiotropic activities which cannot be fully explained by the stimulation of classic pathway- and vitamin D receptor (VDR)-dependent transcriptional modulation. Thus, existence of rapid and nongenomic responses to vitamin D was suggested. An active form of vitamin D (calcitriol, 1,25(OH)2D3) is an essential regulator of calcium-phosphate homeostasis, and this process is tightly regulated by VDR genomic activity. However, it seems that early in evolution, the production of secosteroids (vitamin-D-like steroids) and their subsequent photodegradation served as a protective mechanism against ultraviolet radiation and oxidative stress. Consequently, direct cell-protective activities of vitamin D were proven. Furthermore, calcitriol triggers rapid calcium influx through epithelia and its uptake by a variety of cells. Subsequently, protein disulfide-isomerase A3 (PDIA3) was described as a membrane vitamin D receptor responsible for rapid nongenomic responses. Vitamin D was also found to stimulate a release of secondary massagers and modulate several intracellular processes-including cell cycle, proliferation, or immune responses-through wingless (WNT), sonic hedgehog (SSH), STAT1-3, or NF-kappaB pathways. Megalin and its coreceptor, cubilin, facilitate the import of vitamin D complex with vitamin-D-binding protein (DBP), and its involvement in rapid membrane responses was suggested. Vitamin D also directly and indirectly influences mitochondrial function, including fusion-fission, energy production, mitochondrial membrane potential, activity of ion channels, and apoptosis. Although mechanisms of the nongenomic responses to vitamin D are still not fully understood, in this review, their impact on physiology, pathology, and potential clinical applications will be discussed.
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Affiliation(s)
- Michał A Żmijewski
- Department of Histology, Faculty of Medicine, Medical University of Gdańsk, PL-80211 Gdańsk, Poland
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Boyan BD, Asmussen NC, Lin Z, Schwartz Z. The Role of Matrix-Bound Extracellular Vesicles in the Regulation of Endochondral Bone Formation. Cells 2022; 11:1619. [PMID: 35626656 PMCID: PMC9139584 DOI: 10.3390/cells11101619] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/01/2022] [Accepted: 05/09/2022] [Indexed: 02/04/2023] Open
Abstract
Matrix vesicles are key players in the development of the growth plate during endochondral bone formation. They are involved in the turnover of the extracellular matrix and its mineralization, as well as being a vehicle for chondrocyte communication and regulation. These extracellular organelles are released by the cells and are anchored to the matrix via integrin binding to collagen. The exact function and makeup of the vesicles are dependent on the zone of the growth plate in which they are produced. Early studies defined their role as sites of initial calcium phosphate deposition based on the presence of crystals on the inner leaflet of the membrane and subsequent identification of enzymes, ion transporters, and phospholipid complexes involved in mineral formation. More recent studies have shown that they contain small RNAs, including microRNAs, that are distinct from the parent cell, raising the hypothesis that they are a distinct subset of exosomes. Matrix vesicles are produced under complex regulatory pathways, which include the action of steroid hormones. Once in the matrix, their maturation is mediated by the action of secreted hormones. How they convey information to cells, either through autocrine or paracrine actions, is now being elucidated.
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Affiliation(s)
- Barbara D. Boyan
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA;
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Niels C. Asmussen
- School of Integrated Life Sciences, Virginia Commonwealth University, Richmond, VA 23284, USA;
| | - Zhao Lin
- Department of Periodontics, School of Dentistry, Virginia Commonwealth University, Richmond, VA 23284, USA;
| | - Zvi Schwartz
- Department of Biomedical Engineering, College of Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA;
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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Rapid Nontranscriptional Effects of Calcifediol and Calcitriol. Nutrients 2022; 14:nu14061291. [PMID: 35334948 PMCID: PMC8951353 DOI: 10.3390/nu14061291] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/11/2022] [Accepted: 03/14/2022] [Indexed: 01/28/2023] Open
Abstract
Classically, a secosteroid hormone, vitamin D, has been implicated in calcium and phosphate homeostasis and has been associated with the pathogenesis of rickets and osteomalacia in patients with severe nutritional vitamin D deficiency. The spectrum of known vitamin D-mediated effects has been expanded in recent years. However, the mechanisms of how exactly this hormone elicits its biological function are still not fully understood. The interaction of this metabolite with the vitamin D receptor (VDR) and, subsequently, with the vitamin D-responsive element in the region of specific target genes leading to the transcription of genes whose protein products are involved in the traditional function of calcitriol (known as genomic actions). Moreover, in addition to these transcription-dependent mechanisms, it has been recognized that the biologically active form of vitamin D3, as well as its immediate precursor metabolite, calcifediol, initiate rapid, non-genomic actions through the membrane receptors that are bound as described for other steroid hormones. So far, among the best candidates responsible for mediating rapid membrane response to vitamin D metabolites are membrane-associated VDR (VDRm) and protein disulfide isomerase family A member 3 (Pdia3). The purpose of this paper is to provide an overview of the rapid, non-genomic effects of calcifediol and calcitriol, whose elucidation could improve the understanding of the vitamin D3 endocrine system. This will contribute to a better recognition of the physiological acute functions of vitamin D3, and it could lead to the identification of novel therapeutic targets able to modulate these actions.
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In Vitro Non-Genomic Effects of Calcifediol on Human Preosteoblastic Cells. Nutrients 2021; 13:nu13124227. [PMID: 34959778 PMCID: PMC8707877 DOI: 10.3390/nu13124227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/20/2021] [Accepted: 11/24/2021] [Indexed: 11/24/2022] Open
Abstract
Several recent studies have demonstrated that the direct precursor of vitamin D3, the calcifediol [25(OH)D3], through the binding to the nuclear vitamin D receptor (VDR), is able to regulate the expression of many genes involved in several cellular processes. Considering that itself may function as a VDR ligand, although with a lower affinity, respect than the active form of vitamin D, we have assumed that 25(OH)D3 by binding the VDR could have a vitamin’s D3 activity such as activating non-genomic pathways, and in particular we selected mesenchymal stem cells derived from human adipose tissue (hADMSCs) for the in vitro assessment of the intracellular Ca2+ mobilization in response to 25(OH)D3. Our result reveals the ability of 25(OH)D3 to activate rapid, non-genomic pathways, such as an increase of intracellular Ca2+ levels, similar to what observed with the biologically active form of vitamin D3. hADMSCs loaded with Fluo-4 AM exhibited a rapid and sustained increase in intracellular Ca2+ concentration as a result of exposure to 10−5 M of 25(OH)D3. In this work, we show for the first time the in vitro ability of 25(OH)D3 to induce a rapid increase of intracellular Ca2+ levels in hADMSCs. These findings represent an important step to better understand the non-genomic effects of vitamin D3 and its role in endocrine system.
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Lu X, Chen Z, Watsky MA. Effects of 1,25 and 24,25 Vitamin D on Corneal Fibroblast VDR and Vitamin D Metabolizing and Catabolizing Enzymes. Curr Eye Res 2021; 46:1271-1282. [PMID: 33535006 DOI: 10.1080/02713683.2021.1884726] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Purpose: To investigate the effects of 1,25-Vit D3 and 24,25-Vit D3 on corneal fibroblast expression of the vitamin D-associated enzymes CYP27B1 and CYP24A1 and the roles of the vitamin D receptor (VDR) and protein disulfide isomerase, family A, member 3 (Pdia3) in these cells.Methods: CYP24A1, CYP27B1, VDR, and Pdia3 expression in corneas was detected using immunohistochemistry. Western blotting was used to measure protein expression in human and mouse fibroblasts, including VDR KO mouse cells, treated with 1,25-Vit D3 (20 nM) and 24,25-Vit D3 (100 nM). The Pdia3 inhibitor LOC14 was used to explore the role of Pdia3 as a Vit D3 receptor in these cells.Results: CYP24A1, CYP27B1, VDR, and Pdia3 were all expressed in mouse and human corneal fibroblasts. 1,25-Vit D3 significantly increased VDR expression in human and mouse fibroblasts. 1,25-Vit D3 and 24,25-VitD3 significantly increased CYP24A1 and CYP27B1 expression level in human, VDR WT mouse, and VDR KO mouse corneal fibroblasts. CYP24A1 and CYP27B1 expression was unchanged in VDR KO mouse fibroblasts treated with 1,25-Vit D3 or 24,25-Vit D3 plus LOC14. Human fibroblast VDR, CYP24A1, and CYP27B1 expression were unaffected by LOC14.Conclusions: Vitamin D metabolic enzymes, VDR, and Pdia3 are all expressed in mouse and human corneal fibroblasts. 1,25-Vit D3 modulates fibroblast vitamin D enzymes through both the VDR and Pdia3 pathways in a species-dependent manner. 24,25-Vit D3 can increase expression of fibroblast CYP24A1 and CYP27B1 in the absence of VDR and is likely involved in fibroblast regulation independent of 1,25-Vit D3 or VDR.
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Affiliation(s)
- Xiaowen Lu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Zhong Chen
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Mitchell A Watsky
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
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Bollen SE, Atherton PJ. Myogenic, genomic and non-genomic influences of the vitamin D axis in skeletal muscle. Cell Biochem Funct 2020; 39:48-59. [PMID: 33037688 DOI: 10.1002/cbf.3595] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/21/2020] [Accepted: 09/27/2020] [Indexed: 12/14/2022]
Abstract
Despite vitamin D-deficiency clinically presenting with myopathy, muscle weakness and atrophy, the mechanisms by which vitamin D exerts its homeostatic effects upon skeletal muscle remain to be fully established. Recent studies have shown that the receptor by which 1α,25-dihydroxyvitamin D3 (1,25[OH]2 D3 ) exerts its biological actions (ie, the vitamin D receptor, VDR) elicits both genomic and non-genomic effects upon skeletal muscle. The controversy surrounding skeletal muscle VDR mRNA/protein expression in post-natal muscle has been allayed by myriad recent studies, while dynamic expression of VDR throughout myogenesis, and association of higher VDR levels during muscle regeneration/immature muscle cells, suggests a role in myogenesis and perhaps an enrichment of VDR in satellite cells. Accordingly, in vitro studies have demonstrated 1,25(OH)2 D3 is anti-proliferative in myoblasts, yet pro-differentiation in latter stages of myogenesis. These effects involve modulation of gene expression (VDR as a transcriptional co-activator controls ~3% of the genome) and post-genomic intracellular signalling for example, via c-Src and alterations to intramuscular calcium homeostasis and proteostasis. The aim of this review is to consider the biomolecular role for the vitamin D/VDR axis in myogenesis, while also exploring global evidence for genomic and non-genomic mechanisms of action for 1,25(OH)2 D3 /VDR.
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Affiliation(s)
- Shelby E Bollen
- MRC/ARUK Centre for Musculoskeletal Ageing Research and National Institute for Health Research (NIHR), Nottingham Biomedical Research Centre (BRC), School of Medicine, University of Nottingham, Derby, UK
| | - Philip J Atherton
- MRC/ARUK Centre for Musculoskeletal Ageing Research and National Institute for Health Research (NIHR), Nottingham Biomedical Research Centre (BRC), School of Medicine, University of Nottingham, Derby, UK
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Zmijewski MA, Carlberg C. Vitamin D receptor(s): In the nucleus but also at membranes? Exp Dermatol 2020; 29:876-884. [PMID: 32654294 DOI: 10.1111/exd.14147] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/10/2020] [Accepted: 06/25/2020] [Indexed: 12/11/2022]
Abstract
The genomic actions of the vitamin D are mediated via its biologically most potent metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ) and the transcription factor vitamin D receptor (VDR). Activation of VDR by 1,25(OH)2 D3 leads to change in the expression of more 1000 genes in various human tissues. Based on (epi)genome, transcriptome and crystal structure data the molecular details of this nuclear vitamin D signalling pathway are well understood. Vitamin D is known for its role on calcium homeostasis and bone formation, but it also modulates energy metabolism, innate and adaptive immunity as well as cellular growth, differentiation and apoptosis. The observation of rapid, non-genomic effects of 1,25(OH)2 D3 at cellular membranes and in the cytosol initiated the question, whether there are alternative vitamin D-binding proteins in these cellular compartments. So far, the best candidate is the enzyme PDIA3 (protein disulphide isomerase family A member 3), which is found at various subcellular locations. Furthermore, also VDR seems to play a role in membrane-based responses to vitamin D. In this viewpoint, we will dispute whether these rapid, non-genomic pathways are a meaningful addition to the genome-wide effects of vitamin D.
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Affiliation(s)
| | - Carsten Carlberg
- School of Medicine, Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
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13
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Gu J, Tong X, Chen Y, Zhang C, Ma T, Li S, Min W, Yuan Y, Liu X, Bian J, Liu Z. Vitamin D Inhibition of TRPV5 Expression During Osteoclast Differentiation. Int J Endocrinol Metab 2019; 17:e91583. [PMID: 31998380 PMCID: PMC6948119 DOI: 10.5812/ijem.91583] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 07/15/2019] [Accepted: 09/08/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Vitamin D is an important steroid that can regulate bone metabolism including osteoclast (OC) differentiation. Transient receptor potential cation channel subfamily V member 5 (TRPV5), is a calcium channel protein involved in OC differentiation. However, the impact of vitamin D on TRPV5 expression during OC differentiation is not clear. OBJECTIVES To determine if 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) regulates the expression of TRPV5 during OC differentiation. METHODS Bone marrow mononuclear macrophage (BMMs) were induced to differentiate into OC with or without treatment with 10 nM 1,25(OH)2D3. The expression levels of vitamin D receptor (VDR) and TRPV5 were examined. The expression of several OC markers, including tartrate resistant acid phosphatase (TRAP), carbonic anhydrase II (Ca II), cathepsin K (CTSK), and vacuolar-type H+-ATPase (V-ATPase) were also detected. RESULTS We found that the VDR was expressed in murine bone marrow-derived macrophages at the early stage of OC differentiation. TRPV5 expression was increased during OC differentiation, which was down-regulated by 1,25(OH)2D3 after a prolonged exposure. The 1,25(OH)2D3 and TRPV5 inhibitors inhibited OC differentiation. CONCLUSIONS 1,25(OH)2D3 can inhibit TRPV5 expression as well as TRPV5 inhibitors during OC differentiation. This suggests that 1,25(OH)2D3 may suppress OC differentiation by inhibiting TRPV5 expression.
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Affiliation(s)
- Jianhong Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Xishuai Tong
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Yang Chen
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Chuang Zhang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Tianhong Ma
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Saihui Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Wenyan Min
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Yan Yuan
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Xuezhong Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Jianchun Bian
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Zongping Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
- Jiangsu Key Laboratory of Zoonosis, Yangzhou, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
- Corresponding Author: College of Veterinary Medicine, Yangzhou University, Wenhui East Road 48#, Yangzhou, China. Tel: +86-51487991448,
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A Narrative Role of Vitamin D and Its Receptor: With Current Evidence on the Gastric Tissues. Int J Mol Sci 2019; 20:ijms20153832. [PMID: 31387330 PMCID: PMC6695859 DOI: 10.3390/ijms20153832] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/30/2019] [Accepted: 08/01/2019] [Indexed: 02/06/2023] Open
Abstract
Vitamin D is a major steroid hormone that is gaining attention as a therapeutic molecule. Due to the general awareness of its importance for the overall well-being, vitamin D deficiency (VDD) is now recognized as a major health issue. The main reason for VDD is minimal exposure to sunlight. The vitamin D receptor (VDR) is a member of the steroid hormone receptors that induces a cascade of cell signaling to maintain healthy Ca2+ levels that serve to regulate several biological functions. However, the roles of vitamin D and its metabolism in maintaining gastric homeostasis have not yet been completely elucidated. Currently, there is a need to increase the vitamin D status in individuals worldwide as it has been shown to improve musculoskeletal health and reduce the risk of chronic illnesses, including some cancers, autoimmune and infectious diseases, type 2 diabetes mellitus, neurocognitive disorders, and general mortality. The role of vitamin D in gastric homeostasis is crucial and unexplored. This review attempts to elucidate the central role of vitamin D in preserving and maintaining the overall health and homeostasis of the stomach tissue.
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Tuckey RC, Cheng CYS, Slominski AT. The serum vitamin D metabolome: What we know and what is still to discover. J Steroid Biochem Mol Biol 2019; 186:4-21. [PMID: 30205156 PMCID: PMC6342654 DOI: 10.1016/j.jsbmb.2018.09.003] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 09/04/2018] [Accepted: 09/04/2018] [Indexed: 01/08/2023]
Abstract
Vitamin D, referring to the two forms, D2 from the diet and D3 primarily derived from phototransformation in the skin, is a prohormone important in human health. The most hormonally active form, 1α,25-dihydroxyvitamin D (1α,25(OH)2D), formed from vitamin D via 25-hydroxyvitamin D (25(OH)D), is not only important for regulating calcium metabolism, but has many pleiotropic effects including regulation of the immune system and has anti-cancer properties. The major circulating form of vitamin D is 25(OH)D and both D2 and D3 forms are routinely measured by LC/MS/MS to assess vitamin D status, due to their relatively long half-lives and much higher concentrations compared to 1α,25(OH)2D. Inactivation of both 25(OH)D and 1α,25(OH)2D is catalyzed by CYP24A1 and 25-hydroxyvitamin D3 3-epimerase. Initial products from these enzymes acting on 25(OH)D3 are 24R,25(OH)2D3 and 3-epi-25(OH)D3, respectively, and both of these can also be measured routinely in some clinical laboratories to further document vitamin D status. With advances in LC/MS/MS and its increased availability, and with the help of studies with recombinant vitamin D-metabolizing enzymes, many other vitamin D metabolites have now been detected and in some cases quantitated, in human serum. CYP11A1 which catalyzes the first step in steroidogenesis, has been found to also act on vitamins D3 and D2 hydroxylating both at C20, but with some secondary metabolites produced by subsequent hydroxylations at other positions on the side chain. The major vitamin D3 metabolite, 20S-hydroxyvitamin D3 (20S(OH)D3), shows biological activity, often similar to 1α,25(OH)2D3 but without calcemic effects. Using standards produced enzymatically by purified CYP11A1 and characterized by NMR, many of these new metabolites have been detected in human serum, with semi-quantitative measurement of 20S(OH)D3 indicating it is present at comparable concentrations to 24R,25(OH)2D3 and 3-epi-25(OH)D3. Recently, vitamin D-related hydroxylumisterols derived from lumisterol3, a previtamin D3 photoproduct, have also been measured in human serum and displayed biological activity in initial in vitro studies. With the current extensive knowledge on the reactions and pathways of metabolism of vitamin D, especially those catalyzed by CYP24A1, CYP27A1, CYP27B1, CYP3A4 and CYP11A1, it is likely that many other of the resulting hydroxyvitamin D metabolites will be measured in human serum in the future, some contributing to a more detailed understanding of vitamin D status in health and disease.
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Affiliation(s)
- Robert C Tuckey
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia.
| | - Chloe Y S Cheng
- School of Molecular Sciences, The University of Western Australia, Perth, WA, 6009, Australia
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, AL, 35294, USA; Comprehensive Cancer Center Cancer Chemoprevention Program, University of Alabama at Birmingham, AL, 35294, USA; VA Medical Center, Birmingham, AL, 35294, USA
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Tamayo M, Martin-Nunes L, Val-Blasco A, Piedras MJ, Larriba MJ, Gómez-Hurtado N, Fernández-Velasco M, Delgado C. Calcitriol, the Bioactive Metabolite of Vitamin D, Increases Ventricular K + Currents in Isolated Mouse Cardiomyocytes. Front Physiol 2018; 9:1186. [PMID: 30197603 PMCID: PMC6117532 DOI: 10.3389/fphys.2018.01186] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 08/07/2018] [Indexed: 01/20/2023] Open
Abstract
Calcitriol, the bioactive metabolite of vitamin D, interacts with the ubiquitously expressed nuclear vitamin D receptor (VDR) to induce genomic effects, but it can also elicit rapid responses via membrane-associated VDR through mechanisms that are poorly understood. The down-regulation of K+ currents is the main origin of electrophysiological remodeling in pathological hypertrophy and heart failure (HF), which can contribute to action potential prolongation and subsequently increase the risk of triggered arrhythmias. Adult mouse ventricular myocytes were isolated and treated with 10 nM calcitriol or vehicle for 15–30 min. In some experiments, cardiomyocytes were pretreated with the Akt inhibitor triciribine. In the adult mouse ventricle, outward K+ currents involved in cardiac repolarization are comprised of three components: the fast transient outward current (Itof), the ultrarapid delayed rectifier K+ current (Ikur), and the non-inactivating steady-state outward current (Iss). K+ currents were investigated using the whole-cell or the perforated patch-clamp technique and normalized to cell capacitance to obtain current densities. Calcitriol treatment of cardiomyocytes induced an increase in the density of Itof and Ikur, which was lost in myocytes isolated from VDR-knockout mice. In addition, calcitriol activated Akt in cardiomyocytes and pretreatment with triciribine prevented the calcitriol-induced increase of outward K+ currents. In conclusion, we demonstrate that calcitriol via VDR and Akt increases both Itof and Ikur densities in mouse ventricular cardiomyocytes. Our findings may provide new mechanistics clues for the cardioprotective role of this hormone in the heart.
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Affiliation(s)
- María Tamayo
- Biomedical Research Institute "Alberto Sols" CSIC-UAM/CIBER-CV, Madrid, Spain
| | - Laura Martin-Nunes
- Biomedical Research Institute "Alberto Sols" CSIC-UAM/CIBER-CV, Madrid, Spain
| | - Almudena Val-Blasco
- Innate Immune Response Group, IdiPAZ/CIBER-CV, La Paz University Hospital, Madrid, Spain
| | - Maria J Piedras
- Biomedical Research Institute "Alberto Sols" CSIC-UAM/CIBER-CV, Madrid, Spain.,University Francisco de Vitoria, Madrid, Spain
| | - María J Larriba
- Biomedical Research Institute "Alberto Sols" CSIC-UAM/CIBERONC, Madrid, Spain
| | | | | | - Carmen Delgado
- Biomedical Research Institute "Alberto Sols" CSIC-UAM/CIBER-CV, Madrid, Spain
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17
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Lin Z, McClure MJ, Zhao J, Ramey AN, Asmussen N, Hyzy SL, Schwartz Z, Boyan BD. MicroRNA Contents in Matrix Vesicles Produced by Growth Plate Chondrocytes are Cell Maturation Dependent. Sci Rep 2018; 8:3609. [PMID: 29483516 PMCID: PMC5826934 DOI: 10.1038/s41598-018-21517-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 02/06/2018] [Indexed: 01/01/2023] Open
Abstract
Chondrocytes at different maturation states in the growth plate produce matrix vesicles (MVs), membrane organelles found in the extracellular matrix, with a wide range of contents, such as matrix processing enzymes and receptors for hormones. We have shown that MVs harvested from growth zone (GC) chondrocyte cultures contain abundant small RNAs, including miRNAs. Here, we determined whether RNA also exists in MVs produced by less mature resting zone (RC) chondrocytes and, if so, whether it differs from the RNA in MVs produced by GC cells. Our results showed that RNA, small RNA specifically, was present in RC-MVs, and it was well-protected from RNase by the phospholipid membrane. A group of miRNAs was enriched in RC-MVs compared RC-cells, suggesting that miRNAs are selectively packaged into MVs. High throughput array and RNA sequencing showed that ~39% miRNAs were differentially expressed between RC-MVs and GC-MVs. Individual RT-qPCR also confirmed that miR-122-5p and miR-150-5p were expressed at significantly higher levels in RC-MVs compared to GC-MVs. This study showed that growth plate chondrocytes at different differentiation stages produce different MVs with different miRNA contents, further supporting extracellular vesicle miRNAs play a role as “matrisomes” that mediate the cell–cell communication in cartilage and bone development.
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Affiliation(s)
- Zhao Lin
- Department of Periodontics, School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA.,Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Michael J McClure
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Junjun Zhao
- Department of Periodontics, School of Dentistry, Virginia Commonwealth University, Richmond, VA, USA.,Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA.,General Dentistry, 9th People's Hospital, College of Stomatology, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Allison N Ramey
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Niels Asmussen
- School of Integrated Life Science, Virginia Commonwealth University, Richmond, VA, USA
| | - Sharon L Hyzy
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Zvi Schwartz
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA.,Department of Periodontics, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Barbara D Boyan
- Department of Biomedical Engineering, School of Engineering, Virginia Commonwealth University, Richmond, VA, USA. .,Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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18
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Effects of 1,25 and 24,25 Vitamin D on Corneal Epithelial Proliferation, Migration and Vitamin D Metabolizing and Catabolizing Enzymes. Sci Rep 2017; 7:16951. [PMID: 29208972 PMCID: PMC5717139 DOI: 10.1038/s41598-017-16698-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 10/06/2017] [Indexed: 12/19/2022] Open
Abstract
This study investigated the effects of 1,25(OH)2D3 and 24R,25(OH)2D3 on corneal epithelial cell proliferation, migration, and on the vitamin D activating enzyme CYP27B1 (produces 1,25(OH)2D3) and inactivating enzyme CYP24A1 (produces 24R,25(OH)2D3). The role of the vitamin D receptor (VDR) was also examined. In VDR wildtype mouse corneal epithelial cells (WT), 1,25(OH)2D3 increased CYP24A1 protein expression and decreased CYP27B1 expression. In VDR knockout mouse epithelial cells (KO), 1,25(OH)2D3 increased CYP24A1 and CYP27B1 protein expression. 1,25(OH)2D3 did not affect WT cell proliferation, but did stimulate VDR KO cell proliferation. In a human corneal epithelial cell line (HCEC), 1,25(OH)2D3 increased CYP24A1 mRNA and protein expression. 1,25(OH)2D3 increased CYP27B1 mRNA levels in HCEC, but had no effect on CYP27B1 protein levels. 1,25(OH)2D3 inhibited HCEC proliferation and stimulated cell migration in primary human epithelial cells. 24,25(OH)2D3, on the other hand, increased both CYP24A1 and CYP27B1 protein expression in WT and VDR KO cells, and stimulated cell proliferation in both WT and KO cells. In HCEC, 24,25(OH)2D3 increased CYP24A1 and CYP27B1 mRNA and protein expression, and stimulated cell migration. In human primary corneal epithelial cells, 24,25(OH)2D3 stimulated migration. We conclude that 24R,25(OH)2D3 is likely involved in corneal epithelial cell regulation independent of 1,25(OH)2D3 or VDR.
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19
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Schwartz N, Verma A, Bivens CB, Schwartz Z, Boyan BD. Rapid steroid hormone actions via membrane receptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2289-98. [PMID: 27288742 DOI: 10.1016/j.bbamcr.2016.06.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 06/02/2016] [Accepted: 06/07/2016] [Indexed: 12/19/2022]
Abstract
Steroid hormones regulate a wide variety of physiological and developmental functions. Traditional steroid hormone signaling acts through nuclear and cytosolic receptors, altering gene transcription and subsequently regulating cellular activity. This is particularly important in hormonally-responsive cancers, where therapies that target classical steroid hormone receptors have become clinical staples in the treatment and management of disease. Much progress has been made in the last decade in detecting novel receptors and elucidating their mechanisms, particularly their rapid signaling effects and subsequent impact on tumorigenesis. Many of these receptors are membrane-bound and lack DNA-binding sites, functionally separating them from their classical cytosolic receptor counterparts. Membrane-bound receptors have been implicated in a number of pathways that disrupt the cell cycle and impact tumorigenesis. Among these are pathways that involve phospholipase D, phospholipase C, and phosphoinositide-3 kinase. The crosstalk between these pathways has been shown to affect apoptosis and proliferation in cardiac cells, osteoblasts, and chondrocytes as well as cancer cells. This review focuses on rapid signaling by 17β-estradiol and 1α,25-dihydroxy vitamin D3 to examine the integrated actions of classical and rapid steroid signaling pathways both in contrast to each other and in concert with other rapid signaling pathways. This new approach lends insight into rapid signaling by steroid hormones and its potential for use in targeted drug therapies that maximize the benefits of traditional steroid hormone-directed therapies while mitigating their less desirable effects.
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Affiliation(s)
- Nofrat Schwartz
- Department of Otolaryngology, Meir Hospital, Kfar Saba, Israel
| | - Anjali Verma
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, United States
| | - Caroline B Bivens
- School of Art, Virginia Commonwealth University, Richmond, VA, United States
| | - Zvi Schwartz
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, United States; University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Barbara D Boyan
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, United States; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States.
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Tønnesen R, Schwarz P, Hovind PH, Jensen LT. Physical exercise associated with improved BMD independently of sex and vitamin D levels in young adults. Eur J Appl Physiol 2016; 116:1297-304. [PMID: 27146169 PMCID: PMC4911375 DOI: 10.1007/s00421-016-3383-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 04/28/2016] [Indexed: 02/02/2023]
Abstract
Purpose Young men and women accrue the majority of their bone mass in their teens and twenties, where their bone mass peaks (PBM), yet little is known about the roles of physical exercise, vitamin D levels and bone mineral density (BMD) near PBM. Methods To comparatively examine the effect of physical exercise and two vitamin D levels (insufficient s-25[OH]D <50 nmol/L and sufficient s-25[OH]D >80 nmol/L) on the BMD measured at the femoral neck, total hip (bilaterally) and the lumbar spine (L2–L4) in male and female participants approaching PBM. Results The insufficient s-25[OH]D group, median age 21.6 (19.8–22.8) years, and BMI 24.2 ± 5.0 kg/m2 had BMD 0.10 (0.03, 0.17) g/cm2 (p = 0.008) lower at all DXA-scan sites compared to the sufficient s-25[OH]D group, median age 19.5 (19.0–22.3) years, and BMI of 22.6 ± 1.8 kg/m2. Exercise was positively associated with the BMD at all DXA-scan sites (ptrend = 0.0001) and with equal benefit; there was no interaction between exercise and the DXA-scan site (p = 0.09). The male participants did not have a systematically higher BMD than the female participants for all scan sites; only for hips total and femoral neck bilaterally, while it was equal at the lumbar spine. Conclusion The BMD in young healthy adults is associated with physical exercise, independent of sex and s-25[OH]D status. A sufficient s-25[OH]D status was systematically associated with a higher BMD for all levels of exercise. For both sexes and vitamin D levels exercise was equally positively associated with BMD.
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Affiliation(s)
- Rune Tønnesen
- Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Nordre Ringvej 57, Glostrup, 2600, Copenhagen, Denmark.
| | - Peter Schwarz
- Department of Endocrinology PE and Research Centre of Ageing and Osteoporosis, Rigshospitalet, Copenhagen, Denmark
- Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Hambak Hovind
- Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, Nordre Ringvej 57, Glostrup, 2600, Copenhagen, Denmark
| | - Lars Thorbjørn Jensen
- Department of Clinical Physiology and Nuclear Medicine, University Hospital of Herlev, Copenhagen, Denmark
- Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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The Non-Genomic Actions of Vitamin D. Nutrients 2016; 8:135. [PMID: 26950144 PMCID: PMC4808864 DOI: 10.3390/nu8030135] [Citation(s) in RCA: 179] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 02/06/2023] Open
Abstract
Since its discovery in 1920, a great deal of effort has gone into investigating the physiological actions of vitamin D and the impact its deficiency has on human health. Despite this intense interest, there is still disagreement on what constitutes the lower boundary of adequacy and on the Recommended Dietary Allowance. There has also been a major push to elucidate the biochemistry of vitamin D, its metabolic pathways and the mechanisms that mediate its action. Originally thought to act by altering the expression of target genes, it was realized in the mid-1980s that some of the actions of vitamin D were too rapid to be accounted for by changes at the genomic level. These rapid non-genomic actions have attracted as much interest as the genomic actions and they have spawned additional questions in an already busy field. This mini-review attempts to summarise the in vitro and in vivo work that has been conducted to characterise the rapid non-genomic actions, the mechanisms that give rise to these properties and the roles that these play in the overall action of vitamin D at the cellular level. Understanding the effects of vitamin D at the cellular level should enable the design of elegant human studies to extract the full potential of vitamin D to benefit human health.
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Gibson CC, Davis CT, Zhu W, Bowman-Kirigin JA, Walker AE, Tai Z, Thomas KR, Donato AJ, Lesniewski LA, Li DY. Dietary Vitamin D and Its Metabolites Non-Genomically Stabilize the Endothelium. PLoS One 2015; 10:e0140370. [PMID: 26469335 PMCID: PMC4607301 DOI: 10.1371/journal.pone.0140370] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/24/2015] [Indexed: 12/19/2022] Open
Abstract
Vitamin D is a known modulator of inflammation. Native dietary vitamin D3 is thought to be bio-inactive, and beneficial vitamin D3 effects are thought to be largely mediated by the metabolite 1,25(OH)2D3. Reduced serum levels of the most commonly measured precursor metabolite, 25(OH)D3, is linked to an increased risk of multiple inflammatory diseases, including: cardiovascular disease, arthritis, multiple sclerosis, and sepsis. Common to all of these diseases is the disruption of endothelial stability and an enhancement of vascular leak. We previously performed an unbiased chemical suppressor screen on a genetic model of vascular instability, and identified cholecalciferol (D3, dietary Vitamin D3) as a factor that had profound and immediate stabilizing and therapeutic effects in that model. In this manuscript we show that the presumed inactive sterol, D3, is actually a potent and general mediator of endothelial stability at physiologically relevant concentrations. We further demonstrate that this phenomenon is apparent in vitamin D3 metabolites 25(OH)D3 and 1,25(OH)2D3, and that the effects are independent of the canonical transcription-mediated vitamin D pathway. Our data suggests the presence of an alternative signaling modality by which D3 acts directly on endothelial cells to prevent vascular leak. The finding that D3 and its metabolites modulate endothelial stability may help explain the clinical correlations between low serum vitamin D levels and the many human diseases with well-described vascular dysfunction phenotypes.
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Affiliation(s)
- Christopher C. Gibson
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Recursion Pharmaceuticals, LLC, Salt Lake City, Utah, 84108, United States of America
| | - Chadwick T. Davis
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Recursion Pharmaceuticals, LLC, Salt Lake City, Utah, 84108, United States of America
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Weiquan Zhu
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Jay A. Bowman-Kirigin
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Ashley E. Walker
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Zhengfu Tai
- The Key Laboratory for Human Disease Gene Study of Sichuan Province, Institute of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu, Sichuan, 610072, China
| | - Kirk R. Thomas
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Recursion Pharmaceuticals, LLC, Salt Lake City, Utah, 84108, United States of America
| | - Anthony J. Donato
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Lisa A. Lesniewski
- Division of Geriatrics, Department of Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
| | - Dean Y. Li
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Recursion Pharmaceuticals, LLC, Salt Lake City, Utah, 84108, United States of America
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, 84112, United States of America
- The Key Laboratory for Human Disease Gene Study of Sichuan Province, Institute of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu, Sichuan, 610072, China
- Division of Cardiology, Department of Medicine, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Department of Oncological Sciences, University of Utah, Salt Lake City, Utah, 84112, United States of America
- Cardiology Section, VA Salt Lake City Health Care System, Salt Lake City, Utah, 84112, United States of America
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Doroudi M, Olivares-Navarrete R, Boyan BD, Schwartz Z. A review of 1α,25(OH)2D3 dependent Pdia3 receptor complex components in Wnt5a non-canonical pathway signaling. J Steroid Biochem Mol Biol 2015; 152:84-8. [PMID: 25845934 DOI: 10.1016/j.jsbmb.2015.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 03/16/2015] [Accepted: 04/02/2015] [Indexed: 11/17/2022]
Abstract
Wnt5a and 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] regulate endochondral ossification. 1α,25(OH)2D3 initiates its calcium-dependent effects via its membrane-associated receptor, protein disulfide isomerase A3 (Pdia3). 1α,25(OH)2D3 binding to Pdia3 triggers the interaction between Pdia3 and phospholipase A2 (PLA2)-activating protein (PLAA), resulting in downstream activation of calcium/calmodulin-dependent protein kinase II (CaMKII), PLA2, and protein kinase C (PKC). Wnt5a initiates its calcium-dependent effects via binding its receptors Frizzled2 (FZD2) and Frizzled5 (FZD5) and receptor tyrosine kinase-like orphan receptor 2 (ROR2), activating intracellular calcium release and stimulating PKC and CaMKII. Recent efforts to determine the inter-relation between Wnt5a and 1α,25(OH)2D3 signaling pathways have demonstrated that Wnt5a signals through a CaMKII/PLA2/PGE2/PKC cascade in chondrocytes and osteoblasts in which the components of the Pdia3 receptor complex were required. Furthermore, ROR2, but not FZD2 or FZD5, was required to mediate the calcium-dependent actions of 1α,25(OH)2D3. This review provides evidence that 1α,25(OH)2D3 and Wnt5a mediate their calcium-dependent pathways via similar receptor components and proposes that these pathways may interact since they are competing for the same receptor complex components.
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Affiliation(s)
- Maryam Doroudi
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Rene Olivares-Navarrete
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Barbara D Boyan
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA; Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Zvi Schwartz
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA; Department of Periodontics, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78284, USA
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Abstract
1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] is crucial for normal skeletal development and bone homeostasis. Protein disulfide isomerase family A, member 3 (PDIA3) mediates 1α,25(OH)2D3 initiated-rapid membrane signaling in several cell types. To understand its role in regulating skeletal development, we generated Pdia3-deficient mice and examined the physiologic consequence of Pdia3-disruption in embryos and Pdia3+/− heterozygotes at different ages. No mice homozygous for the Pdia3-deletion were found at birth nor were there embryos after E12.5, indicating that targeted disruption of the Pdia3 gene resulted in early embryonic lethality. Pdia3-deficiency also resulted in skeletal manifestations as revealed by µCT analysis of the tibias. In comparison to wild type mice, Pdia3 heterozygous mice displayed expanded growth plates associated with decreased tether formation. Histomorphometry also showed that the hypertrophic zone in Pdia3+/− mice was more cellular than seen in wild type growth plates. Metaphyseal trabecular bone in Pdia3+/− mice exhibited an age-dependent phenotype with lower BV/TV and trabecular numbers, which was most pronounced at 15 weeks of age. Bone marrow cells from Pdia3+/− mice exhibited impaired osteoblastic differentiation, based on reduced expression of osteoblast markers and mineral deposition compared to cells from wild type animals. Collectively, our findings provide in vivo evidence that PDIA3 is essential for normal skeletal development. The fact that the Pdia3+/− heterozygous mice share a similar growth plate and bone phenotype to nVdr knockout mice, suggests that PDIA3-mediated rapid membrane signaling might be an alternative mechanism responsible for 1α,25(OH)2D3’s actions in regulating skeletal development.
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Doroudi M, Chen J, Boyan BD, Schwartz Z. New insights on membrane mediated effects of 1α,25-dihydroxy vitamin D3 signaling in the musculoskeletal system. Steroids 2014; 81:81-7. [PMID: 24291576 DOI: 10.1016/j.steroids.2013.10.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1α,25-Dihydroxy vitamin D3 [1α,25(OH)2D3] acts on cells via classical steroid hormone receptor-mediated gene transcription and by initiating rapid membrane-mediated signaling pathways. Two receptors have been implicated to play roles in 1α,25(OH)2D3 mediated rapid signaling, the classical nuclear vitamin D receptor (VDR) and protein disulfide isomerase, family A, member 3 (Pdia3). Long term efforts to investigate the roles of these two receptors demonstrated thatPdia3 is located in caveolae, where it interacts with phospholipase A2 (PLA2) activating protein (PLAA) and caveolin-1 (Cav-1) to initiate rapid signaling via Ca(++)/calmodulin-dependent protein kinase II (CaMKII), PLA2, phospholipase C (PLC), protein kinase C (PKC), and ultimately the ERK1/2 family of mitogen activated protein kinases (MAPK). VDR is present on the plasma membrane, and it is required for 1α,25(OH)2D3 induced rapid activation of Src. PDIA3+/- mice demonstrate an impaired musculoskeletal phenotype. Moreover, our studies examining mineralization of pre-osteoblasts in 3D culture have shown the physiological importance of Pdia3 and VDR interaction: knockdown of Pdia3 or VDR is characterized by impaired mineralization of the constructs.
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Affiliation(s)
- Maryam Doroudi
- School of Biology, Georgia Institute of Technology, 310 Ferst Dr. NW, Atlanta, GA, USA
| | - Jiaxuan Chen
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Barbara D Boyan
- School of Biology, Georgia Institute of Technology, 310 Ferst Dr. NW, Atlanta, GA, USA; Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA; School of Engineering, Virginia Commonwealth University, 601 West Main Street, Richmond, VA, USA
| | - Zvi Schwartz
- School of Engineering, Virginia Commonwealth University, 601 West Main Street, Richmond, VA, USA; Department of Periodontics, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
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Plasma membrane Pdia3 and VDR interact to elicit rapid responses to 1α,25(OH)2D3. Cell Signal 2013; 25:2362-73. [DOI: 10.1016/j.cellsig.2013.07.020] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 07/19/2013] [Indexed: 12/29/2022]
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Tuohimaa P, Wang JH, Khan S, Kuuslahti M, Qian K, Manninen T, Auvinen P, Vihinen M, Lou YR. Gene expression profiles in human and mouse primary cells provide new insights into the differential actions of vitamin D3 metabolites. PLoS One 2013; 8:e75338. [PMID: 24116037 PMCID: PMC3792969 DOI: 10.1371/journal.pone.0075338] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/12/2013] [Indexed: 01/08/2023] Open
Abstract
1α,25-Dihydroxyvitamin D3 (1α,25(OH)2D3) had earlier been regarded as the only active hormone. The newly identified actions of 25-hydroxyvitamin D3 (25(OH)D3) and 24R,25-dihydroxyvitamin D3 (24R,25(OH)2D3) broadened the vitamin D3 endocrine system, however, the current data are fragmented and a systematic understanding is lacking. Here we performed the first systematic study of global gene expression to clarify their similarities and differences. Three metabolites at physiologically comparable levels were utilized to treat human and mouse fibroblasts prior to DNA microarray analyses. Human primary prostate stromal P29SN cells (hP29SN), which convert 25(OH)D3 into 1α,25(OH)2D3 by 1α-hydroxylase (encoded by the gene CYP27B1), displayed regulation of 164, 171, and 175 genes by treatment with 1α,25(OH)2D3, 25(OH)D3, and 24R,25(OH)2D3, respectively. Mouse primary Cyp27b1 knockout fibroblasts (mCyp27b1−/−), which lack 1α-hydroxylation, displayed regulation of 619, 469, and 66 genes using the same respective treatments. The number of shared genes regulated by two metabolites is much lower in hP29SN than in mCyp27b1−/−. By using DAVID Functional Annotation Bioinformatics Microarray Analysis tools and Ingenuity Pathways Analysis, we identified the agonistic regulation of calcium homeostasis and bone remodeling between 1α,25(OH)2D3 and 25(OH)D3 and unique non-classical actions of each metabolite in physiological and pathological processes, including cell cycle, keratinocyte differentiation, amyotrophic lateral sclerosis signaling, gene transcription, immunomodulation, epigenetics, cell differentiation, and membrane protein expression. In conclusion, there are three distinct vitamin D3 hormones with clearly different biological activities. This study presents a new conceptual insight into the vitamin D3 endocrine system, which may guide the strategic use of vitamin D3 in disease prevention and treatment.
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Affiliation(s)
- Pentti Tuohimaa
- Department of Anatomy, Medical School, University of Tampere, Tampere, Finland
- Department of Clinical Chemistry, Tampere University Hospital, University of Tampere, Tampere, Finland
| | - Jing-Huan Wang
- Department of Anatomy, Medical School, University of Tampere, Tampere, Finland
- Tampere Graduate School in Biomedicine and Biotechnology, University of Tampere, Tampere, Finland
- Drug Discovery Graduate School, University of Turku, Turku, Finland
| | - Sofia Khan
- Institute of Biomedical Technology and BioMediTech, University of Tampere, Tampere, Finland
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Marianne Kuuslahti
- Department of Anatomy, Medical School, University of Tampere, Tampere, Finland
| | - Kui Qian
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Tommi Manninen
- Department of Cell Biology, Medical School, University of Tampere, Tampere, Finland
| | - Petri Auvinen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Mauno Vihinen
- Institute of Biomedical Technology and BioMediTech, University of Tampere, Tampere, Finland
- Institute of Experimental Medical Science, Lund University, Lund, Sweden
- Tampere University Hospital, Tampere, Finland
| | - Yan-Ru Lou
- Division of Biopharmaceutics and Pharmacokinetics, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
- * E-mail:
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Chen J, Dosier CR, Park JH, De S, Guldberg RE, Boyan BD, Schwartz Z. Mineralization of three-dimensional osteoblast cultures is enhanced by the interaction of 1α,25-dihydroxyvitamin D3 and BMP2 via two specific vitamin D receptors. J Tissue Eng Regen Med 2013; 10:40-51. [DOI: 10.1002/term.1770] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 04/16/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Jiaxuan Chen
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Christopher R. Dosier
- Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Jung Hwa Park
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Subhendu De
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Robert E. Guldberg
- Woodruff School of Mechanical Engineering; Georgia Institute of Technology; Atlanta GA USA
| | - Barbara D. Boyan
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology; Atlanta GA USA
- Department of Biomedical Engineering; Virginia Commonwealth University; Richmond VA USA
| | - Zvi Schwartz
- Wallace H. Coulter Department of Biomedical Engineering; Georgia Institute of Technology; Atlanta GA USA
- Department of Biomedical Engineering; Virginia Commonwealth University; Richmond VA USA
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Chen J, Lobachev KS, Grindel BJ, Farach-Carson MC, Hyzy SL, El-Baradie KB, Olivares-Navarrete R, Doroudi M, Boyan BD, Schwartz Z. Chaperone properties of pdia3 participate in rapid membrane actions of 1α,25-dihydroxyvitamin d3. Mol Endocrinol 2013; 27:1065-77. [PMID: 23660595 DOI: 10.1210/me.2012-1277] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Protein disulfide isomerase family A, member 3 (Pdia3) mediates many of the plasma membrane (PM)-associated rapid responses to 1α,25-dihydroxyvitamin D3 (1α,25[OH]2D3). It is not well understood how Pdia3, which is an endoplasmic reticulum (ER) chaperone, functions as a PM receptor for 1α,25(OH)2D3. We mutated 3 amino acids (K214 and R282 in the calreticulin interaction site and C406 in the isomerase catalytic site), which are important for Pdia3's ER chaperone function, and examined their role in responses to 1α,25(OH)2D3. Pdia3 constructs with and without the ER retention signal KDEL were used to investigate the PM requirement for Pdia3. Finally, we determined whether palmitoylation and/or myristoylation were required for Pdia3-mediated responses to 1α,25(OH)2D3. Overexpressing the Pdia3 R282A mutant in MC3T3-E1 cells increased PM phospholipase A2-activating protein, Rous sarcoma oncogene (c-Src), and caveolin-1 but blocked increases in 1α,25(OH)2D3-stimulated protein kinase C (PKC) seen in cells overexpressing wild-type Pdia3 (Pdia3Ovr cells). Cells overexpressing Pdia3 with K214A and C406S mutations had PKC activity comparable to untreated controls, indicating that the native response to 1α,25(OH)2D3 also was blocked. Overexpressing Pdia3[-KDEL] increased PM localization and augmented baseline PKC, but the stimulatory effect of 1α,25(OH)2D3 was comparable to that seen in wild-type cultures. In contrast, 1α,25(OH)2D3 increased prostaglandin E2 in Pdia3[±KDEL] cells. Although neither palmitoylation nor myristoylation was required for PM association of Pdia3, myristoylation was needed for PKC activation. These data indicate that both the chaperone functional domains and the subcellular location of Pdia3 control rapid membrane responses to 1α,25(OH)2D3.
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Affiliation(s)
- Jiaxuan Chen
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Phospholipases of mineralization competent cells and matrix vesicles: roles in physiological and pathological mineralizations. Int J Mol Sci 2013; 14:5036-129. [PMID: 23455471 PMCID: PMC3634480 DOI: 10.3390/ijms14035036] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 02/08/2023] Open
Abstract
The present review aims to systematically and critically analyze the current knowledge on phospholipases and their role in physiological and pathological mineralization undertaken by mineralization competent cells. Cellular lipid metabolism plays an important role in biological mineralization. The physiological mechanisms of mineralization are likely to take place in tissues other than in bones and teeth under specific pathological conditions. For instance, vascular calcification in arteries of patients with renal failure, diabetes mellitus or atherosclerosis recapitulates the mechanisms of bone formation. Osteoporosis—a bone resorbing disease—and rheumatoid arthritis originating from the inflammation in the synovium are also affected by cellular lipid metabolism. The focus is on the lipid metabolism due to the effects of dietary lipids on bone health. These and other phenomena indicate that phospholipases may participate in bone remodelling as evidenced by their expression in smooth muscle cells, in bone forming osteoblasts, chondrocytes and in bone resorbing osteoclasts. Among various enzymes involved, phospholipases A1 or A2, phospholipase C, phospholipase D, autotaxin and sphingomyelinase are engaged in membrane lipid remodelling during early stages of mineralization and cell maturation in mineralization-competent cells. Numerous experimental evidences suggested that phospholipases exert their action at various stages of mineralization by affecting intracellular signaling and cell differentiation. The lipid metabolites—such as arachidonic acid, lysophospholipids, and sphingosine-1-phosphate are involved in cell signaling and inflammation reactions. Phospholipases are also important members of the cellular machinery engaged in matrix vesicle (MV) biogenesis and exocytosis. They may favour mineral formation inside MVs, may catalyse MV membrane breakdown necessary for the release of mineral deposits into extracellular matrix (ECM), or participate in hydrolysis of ECM. The biological functions of phospholipases are discussed from the perspective of animal and cellular knockout models, as well as disease implications, development of potent inhibitors and therapeutic interventions.
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Boyan BD, Chen J, Schwartz Z. Mechanism of Pdia3-dependent 1α,25-dihydroxy vitamin D3 signaling in musculoskeletal cells. Steroids 2012; 77:892-6. [PMID: 22569272 DOI: 10.1016/j.steroids.2012.04.018] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/14/2012] [Accepted: 04/25/2012] [Indexed: 12/29/2022]
Abstract
1α,25-Dihydroxy vitamin D3 [1,25(OH)2D3] acts on cells through traditional steroid hormone receptor-mediated gene transcription and by initiating rapid membrane-associated signaling pathways. Two receptors have been implicated in rapid signaling by 1,25(OH)2D3, the classical nuclear vitamin D receptor (VDR) and the more recently identified protein disulfide isomerase, family A, member 3 (Pdia3). Our lab along with other groups has established various tools to investigate the role of these two receptors, including gene knock-out, conditional knock-out, silencing, and over-expression in various model systems (growth plate chondrocytes, osteoblastic cells, chick intestinal epithelial cells, mouse embryoid bodies, extracellular matrix vesicles and isolated cell membranes). The data demonstrate the requirement for Pdia3 in 1,25(OH)2D3 induced phospholipase A2 (PLA2) and protein kinase C (PKC) activation and downstream responses. Pdia3+/- heterozygote mice also exhibit both cartilage and bone defects. VDR is present on the plasma membrane and one VDR-/- mouse strain lacks transcaltachia, although 1,25(OH)2D3 induced PKC activation and transcaltachia are not affected in another VDR-/- mouse strain. In the context of osteoblast differentiation, both receptors are expressed during osteogenic commitment of embryoid bodies and silencing of each causes a more mature osteoblast phenotype in MC3T3-E1 pre-osteoblasts. Pdia3 exists in caveolae, where it interacts with PLA2 activating protein (PLAA) and caveolin-1 to initiate rapid signaling via PLA2, phospholipase C (PLC), PKC, and ultimately the ERK1/2 family of mitogen activated protein kinases (MAPK). Using the growth plate chondrocyte and matrix vesicle models, we have demonstrated that Pdia3-dependent signaling in response to 1,25(OH)2D3 regulates growth plate physiology.
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Affiliation(s)
- Barbara D Boyan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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Willems HME, van den Heuvel EGHM, Carmeliet G, Schaafsma A, Klein-Nulend J, Bakker AD. VDR dependent and independent effects of 1,25-dihydroxyvitamin D3 on nitric oxide production by osteoblasts. Steroids 2012; 77:126-31. [PMID: 22093484 DOI: 10.1016/j.steroids.2011.10.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 09/30/2011] [Accepted: 10/31/2011] [Indexed: 01/01/2023]
Abstract
1,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) strongly mediates bone mass. Mechanical stimulation also affects bone mass, partly via enhancing nitric oxide (NO) production by osteoblasts. We aimed to determine whether 1,25(OH)(2)D(3) affects NO production by osteoblasts in the presence or absence of mechanical stimulation. We hypothesised that 1,25(OH)(2)D(3) stimulates NO production via nuclear actions of the vitamin D receptor (VDR), which requires hours of incubation with 1,25(OH)(2)D(3) to occur. MC3T3-E1 osteoblasts and long-bone osteoblasts of adult wildtype and VDR(-/-) mice were pre-incubated for 24h with or without 1,25(OH)(2)D(3) (10(-13)-10(-9)M), followed by 30 min pulsating fluid flow (PFF; 0.7±0.3 Pa, 5 Hz) or static culture with or without 1,25(OH)(2)D(3). NO production and NO synthase (NOS) expression were quantified. 10(-11)M 1,25(OH)(2)D(3) for 24h, but not 30 min, stimulated NO production by MC3T3-E1 osteoblasts (eightfold). 1,25(OH)(2)D(3) for 24h increased inducible-NOS gene-expression (twofold), suggesting that 1,25(OH)(2)D(3) stimulated NO production via activation of NOS gene transcription. PFF rapidly increased NO production by MC3T3-E1 osteoblasts, wildtype osteoblasts, and VDR(-/-) osteoblasts. This PFF effect was abolished after incubation with 1,25(OH)(2)D(3) for 24h, or during PFF only. Our results suggest that 1,25(OH)(2)D(3) stimulates inducible-NOS expression and NO production by osteoblasts in the absence of mechanical stimulation, likely via genomic VDR action. In contrast, 1,25(OH)(2)D(3) may affect mechanical loading-induced NO production independent of genomic VDR action, since 1,25(OH)(2)D(3) diminished PFF-induced NO production in VDR(-/-) bone cells. In conclusion, 1,25(OH)(2)D(3) and mechanical loading interact at the level of mechanotransduction, whereby 1,25(OH)(2)D(3) seems to act independently of VDR genomic mechanism.
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Affiliation(s)
- Hubertine M E Willems
- Department of Oral Cell Biology, ACTA-University of Amsterdam and VU University Amsterdam, Amsterdam, The Netherlands.
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St-Arnaud R, Naja RP. Vitamin D metabolism, cartilage and bone fracture repair. Mol Cell Endocrinol 2011; 347:48-54. [PMID: 21664253 DOI: 10.1016/j.mce.2011.05.018] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 04/26/2011] [Accepted: 05/02/2011] [Indexed: 12/19/2022]
Abstract
The 1,25-(OH)(2)D metabolite mediates the endocrine actions of vitamin D by regulating in the small intestine the expression of target genes that play a critical role in intestinal calcium absorption. The major role of the vitamin D hormone on bone is indirect and mediated through its endocrine function on mineral homeostasis. However, genetic manipulation of the expression of Cyp27b1 or the VDR in chondrocytes strongly support a direct role for locally synthesized 1,25(OH)(2)D, acting through the VDR, in vascular invasion and osteoclastogenesis during endochondral bone development. Cells from the growth plate respond to the 24,25-(OH)(2)D and 1,25-(OH)(2)D metabolites in a cell maturation-dependent manner and the effects of 1,25-(OH)(2)D are thought to be mediated through binding to the membrane-associated receptor PDIA3 (protein disulfide isomerase associated 3). The physiological relevance of membrane-mediated 1,25-(OH)(2)D signaling is emerging and is discussed. Finally, preliminary results suggest that mice deficient for Cyp24a1 exhibit a delay in bone fracture healing and support a role for 24,25-(OH)(2)D in mammalian fracture repair.
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Affiliation(s)
- René St-Arnaud
- Genetics Unit, Shriners Hospital for Children, Montreal, Quebec, Canada H3G 1A6.
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Lee CSD, Chen J, Wang Y, Williams JK, Ranly DM, Schwartz Z, Boyan BD. Coordinated tether formation in anatomically distinct mice growth centers is dependent on a functional vitamin D receptor and is tightly linked to three-dimensional tissue morphology. Bone 2011; 49:419-27. [PMID: 21601024 DOI: 10.1016/j.bone.2011.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 04/27/2011] [Accepted: 05/04/2011] [Indexed: 11/17/2022]
Abstract
Bone bridges linking the epiphysis and metaphysis termed "tethers" have been found in the femoral growth plates of C57Bl/6 mice and are disrupted when the vitamin D receptor (VDR) is ablated. It is unknown if tethers are found in other growth centers, if they are regulated in a comparable manner, or if they have a functional role in skeletal development or stability. To address this, distal femoral growth plates (GPs) and spheno-occipital synchondroses (SOSs) of wild-type C57Bl/6 mice from 2 to 15 weeks of age were analyzed using μCT scans. The GPs and SOSs of VDR+/+ and VDR-/- mice fed regular or rescue diets to restore mineral homeostasis until 10 weeks of age were also scanned. Tethers in GPs and SOSs both thickened and accumulated in number as these growth centers decreased in size. Ablating the VDR made GPs and SOSs rachitic and nearly eliminated tether formation. Rescue diets restored the volume of both growth centers but only partially restored growth center thickness and tether formation, suggesting that lα,25-dihydroxy vitamin D(3) partially regulates tether formation in these growth centers via its receptor. In VDR+/+ mice 2-15 weeks in age, growth center thickness was inversely correlated to animal weight whereas tether phenotype (tether volume/growth center volume, tether number/mm, tether width, tether spacing) was significantly related to animal weight. In both 2-15 week old VDR+/+ and 10 week old VDR+/+ and VDR-/- mice on normal and rescue diets, tether phenotype (tether number/mm, tether spacing) had strikingly similar relationships to growth center thickness. These results show that tethers are present in growth centers in different anatomic and undergo developmental changes in a comparable manner; in both sites, VDR-regulated tether formation is strongly linked to growth center morphology; and tether formation is associated with body weight, suggesting a role in maintaining growth plate stability during growth.
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Affiliation(s)
- Christopher S D Lee
- Wallace H. Coulter Department of Biomedical Engineering and Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0363, USA
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Dyck MC, Ma DWL, Meckling KA. The anticancer effects of Vitamin D and omega-3 PUFAs in combination via cod-liver oil: One plus one may equal more than two. Med Hypotheses 2011; 77:326-32. [DOI: 10.1016/j.mehy.2011.05.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 03/24/2011] [Accepted: 05/02/2011] [Indexed: 01/06/2023]
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Karimian E, Chagin AS, Sävendahl L. Genetic regulation of the growth plate. Front Endocrinol (Lausanne) 2011; 2:113. [PMID: 22654844 PMCID: PMC3356134 DOI: 10.3389/fendo.2011.00113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 12/20/2011] [Indexed: 12/12/2022] Open
Abstract
The epiphyseal growth plate consists of a layer of cartilage present only during the growth period and vanishes soon after puberty in long bones. It is divided to three well-defined zones, from epiphyses; resting, proliferative, and hypertrophic zones. Chondrocyte proliferation and differentiation and subsequent bone formation in this cartilage are controlled by various endocrine, autocrine, and paracrine factors which finally results into elimination of the cartilaginous tissue and promotion of the epiphyseal fusion. As chondrocytes differentiate from round, quiescent, and single structure to flatten and proliferative and then large and terminally differentiated, they experience changes in their gene expression pattern which allow them to transform from cartilaginous tissue to bone. This review summarizes the literature in this area and shortly describes different factors that affect growth plate cartilage both at the local and systemic levels. This may eventually help us to develop new treatment strategies of different growth disorders.
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Affiliation(s)
- Elham Karimian
- Pediatric Endocrinology Unit, Department of Women’s and Children’s Health, Karolinska InstitutetStockholm, Sweden
- *Correspondence: Elham Karimian, Pediatric Endocrinology Unit Q2:08, Karolinska University Hospital, 171 76 Stockholm, Sweden. e-mail:
| | - Andrei S. Chagin
- Pediatric Endocrinology Unit, Department of Women’s and Children’s Health, Karolinska InstitutetStockholm, Sweden
| | - Lars Sävendahl
- Pediatric Endocrinology Unit, Department of Women’s and Children’s Health, Karolinska InstitutetStockholm, Sweden
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Hurst-Kennedy J, Zhong M, Gupta V, Boyan BD, Schwartz Z. 24R,25-Dihydroxyvitamin D3, lysophosphatidic acid, and p53: a signaling axis in the inhibition of phosphate-induced chondrocyte apoptosis. J Steroid Biochem Mol Biol 2010; 122:264-71. [PMID: 20594980 DOI: 10.1016/j.jsbmb.2010.05.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 05/23/2010] [Accepted: 05/27/2010] [Indexed: 11/20/2022]
Abstract
Maintenance of the pool of chondrocytes in the resting zone of the growth plate in the presence of the physiological apoptogen inorganic phosphate (Pi) is crucial for skeletal development. Costochondral resting zone chondrocytes are regulated by the vitamin D metabolite 24R,25-dihydroxyvitamin D3 [24R,25(OH)(2)D(3)], with increased production of sulfated glycosaminoglycan-rich extracellular matrix, and reduced matrix metalloproteinase activity. The effects of 24R,25(OH)(2)D(3) are mediated by activation of phospholipase D (PLD), resulting in increased production of lysophosphatidic acid (LPA) and LPA-mediated proliferation, maturation, inhibition of Pi-induced apoptosis, and reduction of p53. However, the exact mechanism by which 24R,25(OH)(2)D(3) and LPA exert their effects is not fully understood. It was found that both 24R,25(OH)(2)D(3) and LPA attenuate Pi-induced caspase-3 activity. The actions of 24R,25(OH)(2)D(3) and LPA were dependent upon G(αi), LPA receptor(s) 1 and/or 3, PLD, phospholipase C (PLC), and intracellular calcium, phosphoinositide 3-kinase (PI(3)K) signaling, and nuclear export. 24R,25(OH)(2)D(3) decreased both p53 abundance and p53-medaited transcription and inhibited Pi-induced cytochrome c translocation. Moreover, LPA induced increased mdm2 phosphorylation, a negative regulator of p53. Taken together, these data show that 24R,25(OH)(2)D(3) inhibits Pi-induced apoptosis through Ca(2+), PLD, and PLC signaling and through LPA-LPA1/3-G(αi)-PI(3)K-mdm2-mediated p53 degradation, resulting in decreased cytochrome c translocation and caspase-3 activity.
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Affiliation(s)
- J Hurst-Kennedy
- Department of Biomedical Engineering, School of Biology, Georgia Institute of Technology, Atlanta, GA 30332-0363, United States
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Chen J, Olivares-Navarrete R, Wang Y, Herman TR, Boyan BD, Schwartz Z. Protein-disulfide isomerase-associated 3 (Pdia3) mediates the membrane response to 1,25-dihydroxyvitamin D3 in osteoblasts. J Biol Chem 2010; 285:37041-50. [PMID: 20843786 DOI: 10.1074/jbc.m110.157115] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Protein-disulfide isomerase-associated 3 (Pdia3) is a multifunctional protein hypothesized to be a membrane receptor for 1,25(OH)(2)D(3). In intestinal epithelium and chondrocytes, 1,25(OH)(2)D(3) stimulates rapid membrane responses that are different from genomic effects via the vitamin D receptor (VDR). In this study, we show that 1,25(OH)(2)D(3) stimulates phospholipase A(2) (PLA(2))-dependent rapid release of prostaglandin E(2) (PGE(2)), activation of protein kinase C (PKC), and regulation of bone-related gene transcription and mineralization in osteoblast-like MC3T3-E1 cells (WT) via a mechanism involving Pdia3. Pdia3 was present in caveolae based on co-localization with lipid rafts and caveolin-1. In Pdia3-silenced (Sh-Pdia3) cells, 1,25(OH)(2)D(3) failed to stimulate PKC and PGE(2) responses; in Pdia3-overexpressing cells (Ov-Pdia3), responses to 1,25(OH)(2)D(3) were augmented. Downstream mediators of Pdia3, PLA(2)-activating protein (PLAA) and arachidonic acid, stimulated similar PKC activation in wild-type, Sh-Pdia3, and Ov-Pdia3 cells supporting the hypothesis that Pdia3 mediates the membrane action of 1,25(OH)(2)D(3). Treatment of MC3T3-E1 cells with 1,25(OH)(2)D(3) for 9 min stimulated rapid phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and increased expression of alkaline phosphatase, MMP-13, and osteopontin but decreased expression of osteocalcin, osteoprotegerin (mRNA and protein), and smad2. These effects were attenuated in Sh-Pdia3 cells. Sh-Pdia3 cells produced higher numbers of von Kossa-positive nodules and alizarin red-positive nodules compared with WT cells with or without 1,25(OH)(2)D(3) treatment whereas Ov-Pdia3 did not show any mineralization. Our data suggest Pdia3 is an important initiator of 1,25(OH)(2)D(3)-stimulated membrane signaling pathways, which have both genomic and non genomic effects during osteoblast maturation.
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Affiliation(s)
- Jiaxuan Chen
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0363, USA
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Boyan BD, Hurst-Kennedy J, Denison TA, Schwartz Z. 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] controls growth plate development by inhibiting apoptosis in the reserve zone and stimulating response to 1alpha,25(OH)2D3 in hypertrophic cells. J Steroid Biochem Mol Biol 2010; 121:212-6. [PMID: 20307662 DOI: 10.1016/j.jsbmb.2010.03.057] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 03/13/2010] [Accepted: 03/15/2010] [Indexed: 10/19/2022]
Abstract
Previously we showed that costochondral growth plate resting zone (RC) chondrocytes response primarily to 24R,25(OH)2D3 whereas prehypertrophic and hypertrophic (GC) cells respond to 1alpha,25(OH)2D3. 24R,25(OH)2D3 increases RC cell proliferation and inhibits activity of matrix processing enzymes, suggesting it stabilizes cells in the reserve zone, possibly by inhibiting the matrix degradation characteristic of apoptotic hypertrophic GC cells. To test this, apoptosis was induced in rat RC cells by treatment with exogenous inorganic phosphate (Pi). 24R,25(OH)2D3 blocked apoptotic effects in a dose-dependent manner. Similarly, apoptosis was induced in ATDC5 cell cultures and 24R,25(OH)2D3 blocked this effect. Further studies indicated that 24R,25(OH)2D3 acts via at least two independent pathways. 24R,25(OH)2D3 increases LPA receptor-1 (LPA R1) expression and production of lysophosphatidic acid (LPA), and subsequent LPA R1/3-dependent signaling, thereby decreasing p53 abundance. LPA also increases the Bcl-2/Bax ratio. In addition, 24R,25(OH)2D3 acts by increasing PKC activity. 24R,25(OH)2D3 stimulates 1-hydroxylase activity, resulting in increased levels of 1,25(OH)2D3, and it increases levels of phospholipase A2 activating protein, which is required for rapid 1alpha,25(OH)2D3-dependent activation of PKC in GC cells. These results suggest that 24R,25(OH)2D3 modulates growth plate development by controlling the rate and extent of RC chondrocyte transition to a GC chondrocyte phenotype.
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Affiliation(s)
- B D Boyan
- Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, ATlanta, GA 30332-0363, USA.
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Wang Y, Chen J, Lee CSD, Nizkorodov A, Riemenschneider K, Martin D, Hyzy S, Schwartz Z, Boyan BD. Disruption of Pdia3 gene results in bone abnormality and affects 1alpha,25-dihydroxy-vitamin D3-induced rapid activation of PKC. J Steroid Biochem Mol Biol 2010; 121:257-60. [PMID: 20576531 DOI: 10.1016/j.jsbmb.2010.05.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 05/05/2010] [Accepted: 05/10/2010] [Indexed: 11/27/2022]
Abstract
1,25-dihydroxy-vitamin D3 [1alpha,25(OH)2D3] is a critical regulator of bone development. Protein disulfide isomerase A3 (Pdia3) is a multifunctional protein that has been associated with rapid membrane-initiated signalling by 1alpha,25(OH)2D3 in several cell types. To identify the physiological roles of Pdia3 in skeletal development, we generated Pdia3-deficient mice. No homozygous mice were observed at birth, indicating that the targeted disruption of the Pdia3 gene resulted in embryonic lethality. Pdia3 deficiency also resulted in skeletal manifestations as revealed by muCT analysis of femurs from 15-week-old heterozygous mice. The Pdia3+/- mice had increased metaphyseal bone volume and trabeculae compared to Pdia3+/+ mice. In contrast, the area and thickness of cortical bone at the femoral mid-diaphysis of Pdia3+/+ mice significantly exceeded that of Pdia3+/- mice. In vitro studies in osteoblast-like MC3T3-E1 cells showed that silencing of Pdia3 abolished 1alpha,25(OH)2D3-induced rapid activation of protein kinase C (PKC) while overexpression of Pdia3 resulted in augmentation of PKC activity by 1alpha,25(OH)2D3. Taken together, these data indicated that Pdia3 plays a crucial role in 1alpha,25(OH)2D3-regulated bone formation and the Pdia3-PKC signalling pathway might be involved in this process.
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Affiliation(s)
- Yun Wang
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0363, USA
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Li J, Fleet JC, Teegarden D. Activation of rapid signaling pathways does not contribute to 1 alpha,25-dihydroxyvitamin D3-induced growth inhibition of mouse prostate epithelial progenitor cells. J Cell Biochem 2009; 107:1031-6. [PMID: 19492419 DOI: 10.1002/jcb.22206] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The active form of vitamin D, 1 alpha,25-dihydroxyvitamin D(3) (1,25(OH)(2)D) inhibits the growth of prostate epithelial cells, however the underlying mechanisms have not been clearly delineated. In the current study, the impact of 1,25(OH)(2)D on the rapid activation of extracellular-regulated kinase (ERK) 1/2 and protein kinase C alpha (PKC alpha), and the role of these pathways in growth inhibition was examined in immortalized mouse prostate epithelial cells, MPEC3, that exhibit stem/progenitor cell characteristics. 1,25(OH)(2)D treatment suppressed the growth of MPEC3 in a dose and time dependent manner (e.g., 21% reduction at three days with 100 nM 1,25(OH)(2)D treatment). However, ERK1/2 activity was not altered by 100 nM 1,25(OH)(2)D treatment for time points from 1 min to 1 h in either serum-containing or serum-free medium. Similarly, PKC alpha activation (translocation onto the plasma membrane) was not regulated by short-term treatment of 100 nM 1,25(OH)(2)D. In conclusion, 1,25(OH)(2)D did not mediate rapid activation of ERK1/2 or PKC alpha in MPEC3 and therefore the growth inhibitory effect of 1,25(OH)(2)D is independent of rapid activation of these signaling pathways in this cell type.
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Affiliation(s)
- Jia Li
- Interdepartmental Nutrition Program, Purdue University, 700 W. State Street, West Lafayette, Indiana 47907, USA
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Chen J, Lee CSD, Coleman RM, Yoon JY, Lohmann CH, Zustin J, Guldberg RE, Schwartz Z, Boyan BD. Formation of tethers linking the epiphysis and metaphysis is regulated by vitamin d receptor-mediated signaling. Calcif Tissue Int 2009; 85:134-45. [PMID: 19506934 DOI: 10.1007/s00223-009-9259-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2009] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
Abstract
Rat tibial growth plates have X-ray opaque tethers that link the epiphysis and metaphysis and increase with age as the growth plate (GP) becomes thinner. To determine if tether formation is a regulated process of GP maturation, we tested the hypotheses that tether properties and distribution can be quantified by micro-computed tomography (microCT), that rachitic GPs typical of vitamin D receptor knockout (VDR(-/-)) mice have fewer tethers and altered tether distribution, and that tether formation is regulated by signaling via the VDR. Distal femoral GPs from VDR(+/+) and VDR(-/-) 8-week-old mice were analyzed with microCT and then processed for decalcified and undecalcified histomorphometry. A wide range of parameters that assessed GP and tether geometry and morphology, along with tether distribution, were measured using both microCT and histology. Growth plates of 10-week-old VDR(+/+) and VDR(-/-) mice on a high-calcium, phosphorus, lactose, and vitamin D(3) rescue diet were also analyzed. Both microCT and histology showed tethers present throughout normal mice GPs, while reduction in tether number and volume percentage occurred in VDR(-/-) GPs with localization to the central region. Decreased shrinkage in the axial direction during decalcified histological processing correlated with tether formation, suggesting mechanical stability due to tethers. Tether formation increased greatly between 8 and 10 weeks. Rescue diets restored VDR(-/-) GP size but not tether volume percentage. Overall, these results demonstrate microCT imaging's utility for analyzing tether formation and suggest that signaling via the VDR plays a pivotal role in tether formation.
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Affiliation(s)
- Jida Chen
- Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0363, USA
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Denison TA, Koch CF, Shapiro IM, Schwartz Z, Boyan BD. Inorganic phosphate modulates responsiveness to 24,25(OH)2D3 in chondrogenic ATDC5 cells. J Cell Biochem 2009; 107:155-62. [PMID: 19288498 DOI: 10.1002/jcb.22111] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Chondrogenic ATDC5 cells were used as a model of in vitro endochondral maturation to study the role of inorganic phosphate (Pi) in the regulation of growth plate chondrocytes by vitamin D3 metabolites. ATDC5 cells that were cultured for 10 days post-confluence in differentiation media and then treated for 24 h with Pi produced a type II collagen matrix based on immunohistochemistry and expressed mRNAs for several chondrocytic markers, including aggrecan, collagen types II and X, cartilage oligomeric matrix protein, and SOX9. Pi also caused a decrease in [(35)S]-sulfate incorporation and stimulated apoptosis, as evidenced by increased DNA fragmentation and caspase-3 activity. In addition, treatment with Pi induced sensitivity to 24,25-dihydroxyvitamin D3 and this effect was both dose-dependent and was blocked by phosphonoformic acid (PFA), a specific inhibitor of sodium dependent type III Pi transporters. Treatment with 24R,25(OH)(2)D(3) reduced cell number and increased alkaline phosphatase specific activity in a dose-dependent manner. Moreover, 24R,25(OH)(2)D(3) reversed the Pi-induced decrease in incorporation of [(3)H]-thymidine and [(35)S]-sulfate incorporation, as well as the Pi-induced increase in apoptosis. These results suggest that Pi acts as an early chondrogenic differentiation factor, inducing response to 24R,25(OH)(2)D(3); treatment of committed chondrocytes with Pi induces apoptosis, but 24R,25(OH)(2)D(3) mitigates these effects, indicating a possible inhibitory feedback loop.
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Affiliation(s)
- Tracy A Denison
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0363, USA
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Pérez-López FR, Chedraui P, Haya J. Review article: vitamin D acquisition and breast cancer risk. Reprod Sci 2009; 16:7-19. [PMID: 19144887 DOI: 10.1177/1933719108327595] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The aim of the study was to focus on the association of vitamin D and breast cancer. METHODS The study of evidence concerning vitamin D's influence on the origin and development of breast cancer from a PubMed and individual searches. RESULTS Body sunlight exposure may reduce the prevalence of breast cancer. However, these studies correspond to global populations of different countries and regions without considering other geographic factors and individual, ethnic, and cultural factors that may affect sunlight exposure. Epidemiological analyses show that low vitamin D ingestion is associated with increased risk of breast cancer. Studies measuring serum vitamin D metabolites in women who were followed many years suggest that low circulating 25-hydroxyvitamin D3 levels are associated with increased breast cancer risk. CONCLUSIONS Although there are controversial results, it seems plausible that sufficient endogenous vitamin D levels may have a protective function on mammary cells, reducing breast cancer risk.
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Affiliation(s)
- Faustino R Pérez-López
- Department of Obstetrics and Gynecology, University of Zaragoza Faculty of Medicine, Clínico de Zaragoza Hospital, Domingo Miral s/n, Zaragoza, Spain.
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Brown WM. Vitamin D, vitamin D analogs (deltanoids) and prostate cancer. Expert Rev Clin Pharmacol 2008; 1:803-13. [PMID: 24410609 DOI: 10.1586/17512433.1.6.803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
'Vitamin D' is a generic term for a family of secosteroids, members of which bind to the vitamin D receptor. Calcitriol, the active form of vitamin D, has antiproliferative effects on many tumor cells. However, clinical use of calcitriol in cancer prevention or therapy is limited because it induces hypercalcemia at the necessary supraphysiological doses. The anti-tumor effects of vitamin D analogs (deltanoids) have been researched extensively; more than 3000 deltanoids have now been described. Prostate cancer is more common in northern geographic regions; mortality decreases with exposure to sunlight. As UV light is necessary for vitamin D synthesis in the skin, it has long been dogma that vitamin D is involved. This review concerns deltanoids that have been assessed for use in treating or preventing prostate cancer.
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Affiliation(s)
- William M Brown
- VaxDesign Corp., 12612 Challenger Parkway, Suite 365, Orlando, FL 32826, USA.
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The direct role of vitamin D on bone homeostasis. Arch Biochem Biophys 2008; 473:225-30. [PMID: 18424254 DOI: 10.1016/j.abb.2008.03.038] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 03/26/2008] [Accepted: 03/27/2008] [Indexed: 12/28/2022]
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Dreier R, Günther BK, Mainz T, Nemere I, Bruckner P. Terminal differentiation of chick embryo chondrocytes requires shedding of a cell surface protein that binds 1,25-dihydroxyvitamin D3. J Biol Chem 2007; 283:1104-12. [PMID: 17984094 DOI: 10.1074/jbc.m703336200] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Endochondral ossification comprises a cascade of cell differentiation culminating in chondrocyte hypertrophy and is negatively controlled by soluble environmental mediators at several checkpoints. Proteinases modulate this control by processing protein signals and/or their receptors. Here, we show that insulin-like growth factor I can trigger hypertrophic development by stimulating production and/or activation of proteinases in some populations of chick embryo chondrocytes. Cell surface targets of the enzymes include 1,25-dihydroxyvitamin D3 membrane-associated rapid response steroid receptor (1,25 D3 MARRS receptor), also known as ERp57/GRp58/ERp60. This protein is anchored to the outer surface of plasma membranes and inhibits late chondrocyte differentiation after binding of 1,25-dihydroxyvitamin D3. Upon treatment with insulin-like growth factor I, 1,25 D3 MARRS receptor is cleaved into two fragments of approximately 30 and 22 kDa. This process is abrogated along with hypertrophic development by E-64 or cystatin C, inhibitors of cysteine proteinases. Cell differentiation is enhanced by treatment with antibodies to 1,25 D3 MARRS receptor that either block binding of the inhibitory ligand 1,25-dihydroxyvitamin D3 or inactivate 1,25 D3 MARRS receptor left intact after treatment with proteinase inhibitors. Therefore, proteolytic shedding of 1,25 D3 MARRS receptor constitutes a molecular mechanism eliminating the 1,25-dihydroxyvitamin D3-induced barrier against late cartilage differentiation and is a potentially important step during endochondral ossification or cartilage degeneration in osteoarthritis.
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Affiliation(s)
- Rita Dreier
- Institute for Physiological Chemistry and Pathobiochemistry, University Hospital of Münster, 48149 Münster, Germany
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Abstract
A controversy regarding the identity of receptors that mediate nongenomic, transcription-independent cellular responses to steroids is presently attracting considerable scientific interest. While there is strong evidence for classic receptors belonging to the nuclear receptor superfamily to mediate nongenomic steroid effects in some cases, it does not exist for others. Nongenomic estrogen effects seem to predominantly involve classical estrogen receptors, both residing in cytoplasm and at the cell membrane. On the other hand, there is increasing evidence for the existence of nonrelated membrane receptors for estrogens, mediating CNS effects. Novel membrane receptors for other steroids have been recently cloned, with the demonstration of their biological relevance still largely pending. Recent findings on new and unexpected properties of classic receptors have partially deflected the interest from novel, nonclassic membrane receptors, which are being progressively identified at present. In addition, new findings pose challenges to some of the conclusions drawn from earlier experiments, and potential involvement of receptors and mechanisms of action need to be reconsidered. To know the nature of receptors involved will be key to beneficial medical translation of specific and targeted steroid responses. Differential pharmacological exploitation of different steroid receptors seems to become a tangible option.
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Affiliation(s)
- Martin Wehling
- Institute of Clinical Pharmacology Mannheim, University of Heidelberg, Germany.
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Boyan BD, Wong KL, Wang L, Yao H, Guldberg RE, Drab M, Jo H, Schwartz Z. Regulation of growth plate chondrocytes by 1,25-dihydroxyvitamin D3 requires caveolae and caveolin-1. J Bone Miner Res 2006; 21:1637-47. [PMID: 16995819 DOI: 10.1359/jbmr.060713] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
UNLABELLED We examined the role of caveolae and caveolin-1 in the mechanism of 1alpha,25(OH)(2)D(3) action in growth plate chondrocytes. We found that caveolae are required for rapid 1alpha,25(OH)(2)D(3)-dependent PKC signaling, and caveolin-1 must be present based on studies using chondrocytes from Cav-1(-/-) mice. INTRODUCTION 1,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] regulates endochondral ossification in part through membrane-associated mechanisms, including protein kinase C (PKC) signaling activated by a membrane-associated 1alpha,25(OH)(2)D(3)-binding protein, ERp60. We tested the hypothesis that caveolae are required for 1alpha,25(OH)(2)D(3) action and play an important role in regulating chondrocyte biology and growth plate physiology. MATERIALS AND METHODS Rat costochondral chondrocytes were examined for caveolae by transmission electron microscopy of cultured cells and of cells in situ. Western blots and confocal microscopy were used to detect caveolae proteins including caveolin-1 (Cav-1) and 1alpha,25(OH)(2)D(3) receptors. Caveolae cholesterol was depleted with beta-cyclodextrin (CD) and effects of 1alpha,25(OH)(2)D(3) on PKC, DNA synthesis, alkaline phosphatase, and proteoglycan production determined. Chondrocytes from Cav-1(-/-) and C57BL/6 wildtype mice were also treated with 1alpha,25(OH)(2)D(3). Epiphyses and costochondral junctions of 8-week-old male Cav-1(-/-) and wildtype mice (N = 8) were compared by histomorphometry and microCT. Data were analyzed by ANOVA and Bonferroni for posthoc comparisons. RESULTS Growth zone chondrocytes had caveolae and Cav-1, -2, and -3. Resting zone chondrocytes, which do not exhibit a rapid 1alpha,25(OH)(2)D(3)-dependent increase in PKC activity, also had these caveolins, but caveolae were larger and fewer in number. ERp60 but not VDR co-localized with Cav-1 in plasma membranes and in lipid rafts. CD-treatment blocked 1alpha,25(OH)(2)D(3) effects on all parameters tested. The Cav-1(-/-) cells did not respond to 1alpha,25(OH)(2)D(3), although 1alpha,25(OH)(2)D(3) increased PKC, alkaline phosphatase, and [(35)S]-sulfate incorporation in wildtype C57BL/6 cells. Histology and microCT showed that Cav-1(-/-) growth plates were longer and had more hypertrophic cells in each column. Growth plate changes were reflected in the metaphysis. CONCLUSIONS The membrane-mediated effects of 1alpha,25(OH)(2)D(3) require caveolae and Cav-1, and Cav-1 deficiency results in altered growth plate physiology.
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Affiliation(s)
- Barbara D Boyan
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0363, USA.
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Abstract
We have previously demonstrated that modulator of nongenomic action of estrogen receptor (MNAR) integrates action of estrogen receptor alpha (ERalpha), and potentially some other nuclear receptors (NRs), in regulation of Src/Ras/Raf/mitogen-activated protein kinase (MAPK) signaling pathway. MNAR is a scaffolding protein that contains 10 LXXLL type motifs that can interact with NRs and 3 PXXP type motifs that can bind to SH3 domains present in kinases and other signaling molecules. Formation of ER-MNAR-cSrc complex leads to activation of Src and downstream Ras/Raf/MAPK pathway. The goal for this study was to compare MNAR expression in various cell lines, to optimize methods that can be used to manipulate its expression and to evaluate MNAR cellular distribution. We found that MNAR is differentially expressed. The highest levels of its expression were found in fast proliferating cells, such as breast adenocarcinoma (MCF-7)-, T cell lymphoma (Jurkat)-, prostate carcinoma (LNCaP)- and osteosarcoma (SaOS2)-derived cell lines. MNAR was undetectable in African green monkey kidney cells (COS-7) and Chinese hamster ovary cells (CHO-K1). We established and optimized a protocol to knockdown MNAR using siRNA and to overexpress it in MCF-7 cells. Exogenously expressed MNAR was found in both cytoplasmic and nuclear fractions, the majority of MNAR, however, was found in the cytoplasmic fraction. Presence of MNAR in the cell nucleus indicates that it may play a role in regulation of gene expression.
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Affiliation(s)
- James G Greger
- Department of Women's Health and Bone Research Wyeth Research, Collegeville, PA 19426, USA
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