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A comparative analysis of the efficacy and safety of paricalcitol versus other vitamin D receptor activators in patients undergoing hemodialysis: A systematic review and meta-analysis of 15 randomized controlled trials. PLoS One 2020; 15:e0233705. [PMID: 32470067 PMCID: PMC7259607 DOI: 10.1371/journal.pone.0233705] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 05/11/2020] [Indexed: 12/30/2022] Open
Abstract
Paricalcitol, a new vitamin D receptor activator (VDRA), is reported to be more effective than other VDRAs in reducing calcium and phosphorus levels in patients undergoing hemodialysis. However, the efficacy and safety of paricalcitol remain controversial. This analysis compares paricalcitol with other VDRAs in patients undergoing hemodialysis. We searched the Cochrane Library, PubMed, EMBASE, Web of Science, and CNKI up to April 22, 2019. Standardized mean difference (SMD), risk ratio (RR) and 95% confidence interval (CI) values were estimated to compare the outcomes of the groups. Two reviewers extracted data and assessed trial quality independently. All statistical analyses were performed using the standard statistical procedures of RevMan 5.2 and Stata 12.0. Fifteen studies (N = 110,544) were included in this meta-analysis. Of these studies, 11 were randomized controlled trials (RCTs) and 4 were non-randomized studies of interventions (NRSIs). Patients receiving paricalcitol experienced better overall survival (OS) than patients receiving other VDRAs, with a pooled hazard ratio of 0.86 (95% CI 0.80–0.91; P < 0.00001). Intact parathyroid hormone (iPTH) levels were significantly reduced in the paricalcitol group compared to the group receiving other VDRAs, with a pooled SMD of -0.53 (95% CI -0.89– -0.16; P = 0.004). There was a significant increase in serum calcium levels from baseline in the paricalcitol group compared to the other VDRAs group when limiting the analysis to RCTs, with a pooled SMD of 2.14 (95% CI 0.90–3.38; P = 0.0007). Changes in serum calcium levels were significantly lower in the paricalcitol group when the analysis was limited to NRSIs, with a pooled SMD of -0.85 (95% CI -1.34–-0.35; P = 0.0008). The NSRI analysis also showed a significant reduction in serum phosphorus levels in the paricalcitol group, with a pooled SMD of -0.57 (95% CI -1.00–-0.13; P = 0.01). No significant differences were observed in the incidence of hypercalcemia, hyperphosphatemia, or adverse events. Generally, paricalcitol seems superior to other VDRAs in reducing mortality and iPTH levels in patients undergoing hemodialysis. However, the comparative effectiveness of paricalcitol in reducing serum calcium and phosphorus levels needs further exploration. No significant difference was found in the rate of adverse events.
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Goodroe AE, Fitz C, Power ML, Colman RJ, Capuano S, Ziegler TE. Evaluation of vitamin D 3 metabolites in Callithrix jacchus (common marmoset). Am J Primatol 2020; 82:e23131. [PMID: 32270886 DOI: 10.1002/ajp.23131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/15/2020] [Accepted: 03/19/2020] [Indexed: 12/26/2022]
Abstract
Vitamin D3 (cholecalciferol) is endogenously produced in the skin of primates when exposed to the appropriate wavelengths of ultraviolet light (UV-B). Common marmosets (Callithrix jacchus) maintained indoors require dietary provision of vitamin D3 due to lack of sunlight exposure. The minimum dietary vitamin D3 requirement and the maximum amount of vitamin D3 that can be metabolized by marmosets is unknown. Observations of metabolic bone disease and gastrointestinal malabsorption have led to wide variation in dietary vitamin D3 provision amongst research institutions, with resulting variation in circulating 25-hydroxyvitamin D3 (25(OH)D3 ), the accepted marker for vitamin D sufficiency/deficiency. Multiple studies have reported serum 25(OH)D3 in captive marmosets, but 25(OH)D3 is not the final product of vitamin D3 metabolism. In addition to serum 25(OH)D3, we measured the most physiologically active metabolite, 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ), and the less well understood metabolite, 24,25-dihydroxyvitamin D3 (24,25(OH)2 D3 ) to characterize the marmoset's ability to metabolize dietary vitamin D3 . We present vitamin D3 metabolite and related serum chemistry value colony reference ranges in marmosets provided diets with 26,367 (Colony A, N = 113) or 8,888 (Colony B, N = 52) international units (IU) of dietary vitamin D3 per kilogram of dry matter. Colony A marmosets had higher serum 25(OH)D3 (426 ng/ml [SD 200] vs. 215 ng/ml [SD 113]) and 24,25(OH)2 D3 (53 ng/ml [SD 35] vs. 7 ng/ml [SD 5]). There was no difference in serum 1,25(OH)2 D3 between the colonies. Serum 1,25(OH)2 D3 increased and 25(OH)D3 decreased with age, but the effect was weak. Marmosets tightly regulate metabolism of dietary vitamin D3 into the active metabolite 1,25(OH)2 D3 ; excess 25(OH)D3 is metabolized into 24,25(OH)2 D3 . This ability explains the tolerance of high levels of dietary vitamin D3 by marmosets, however, our data suggest that these high dietary levels are not required.
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Affiliation(s)
- Anna E Goodroe
- Veterinary Resources, Southwest National Primate Research Center, San Antonio, Texas
| | - Casey Fitz
- Veterinary Services Unit, Wisconsin National Primate Research Center, Madison, Wisconsin
| | - Michael L Power
- Conservation Ecology Center, Smithsonian National Zoological Park and Conservation Biology Institute, Washington, District of Columbia
| | - Ricki J Colman
- Veterinary Services Unit, Wisconsin National Primate Research Center, Madison, Wisconsin.,Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
| | - Saverio Capuano
- Veterinary Services Unit, Wisconsin National Primate Research Center, Madison, Wisconsin
| | - Toni E Ziegler
- Veterinary Services Unit, Wisconsin National Primate Research Center, Madison, Wisconsin
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Bouillon R, Antonio L. Nutritional rickets: Historic overview and plan for worldwide eradication. J Steroid Biochem Mol Biol 2020; 198:105563. [PMID: 31809867 DOI: 10.1016/j.jsbmb.2019.105563] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/10/2019] [Accepted: 12/02/2019] [Indexed: 02/01/2023]
Abstract
Rickets was first described in great detail in the mid 17th century and was affecting a great number of children in major European cities. The disease, however, existed already in the Roman times. The etiology of this disease remained enigmatic until the 1920s when two different mechanisms, lack of exposure to sunlight and lack of a dietary factor were finally solved by the discovery of vitamin D and its dual origin. Soon thereafter, the implementation of vitamin D supplementation for all infants and small children largely eliminated nutritional rickets in Europe and North America. It took nearly a century to elucidate the complex chemistry, metabolism, mode and spectrum of activity of the vitamin D endocrine system. Nutritional rickets, whether due to simple vitamin D or calcium deficiency or both, remains widely ravaging many infants and children around the world. Asian countries and the Middle East are mainly confronted with vitamin D deficiency whereas many African and some Asian countries face calcium deficiency rickets. Immigrants and refugees or in general people with a darker skin living in moderate climate zone are also confronted with this disease. There is great consensus how this disease could be prevented or cured. In collaboration with most international professional societies, we prepare a memorandum, in line with the successful battle against iodine deficiency disorders, to convince the World Health Organization and its member states to start an implementation program to eradicate nutritional rickets by 2030.
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Affiliation(s)
- Roger Bouillon
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases, Metabolism and Ageing, KU, Leuven, Belgium.
| | - Leen Antonio
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases, Metabolism and Ageing, KU, Leuven, Belgium
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4
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Chun RF, Shieh A, Gottlieb C, Yacoubian V, Wang J, Hewison M, Adams JS. Vitamin D Binding Protein and the Biological Activity of Vitamin D. Front Endocrinol (Lausanne) 2019; 10:718. [PMID: 31708871 PMCID: PMC6821678 DOI: 10.3389/fendo.2019.00718] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 10/04/2019] [Indexed: 12/15/2022] Open
Abstract
Vitamin D has a long-established role in bone health. In the last two decades, there has been a dramatic resurgence in research interest in vitamin D due to studies that have shown its possible benefits for non-skeletal health. Underpinning the renewed interest in vitamin D was the identification of the vital role of intracrine or localized, tissue-specific, conversion of inactive pro-hormone 25-hydroxyvitamin D [25(OH)D] to active 1,25-dihydroxyvitamin D [1,25(OH)2D]. This intracrine mechanism is the likely driving force behind vitamin D action resulting in positive effects on human health. To fully capture the effect of this localized, tissue-specific conversion to 1,25(OH)2D, adequate 25(OH)D would be required. As such, low serum concentrations of 25(OH)D would compromise intracrine generation of 1,25(OH)2D within target tissues. Consistent with this is the observation that all adverse human health consequences of vitamin D deficiency are associated with a low serum 25(OH)D level and not with low 1,25(OH)2D concentrations. Thus, clinical investigators have sought to define what concentration of serum 25(OH)D constitutes adequate vitamin D status. However, since 25(OH)D is transported in serum bound primarily to vitamin D binding protein (DBP) and secondarily to albumin, is the total 25(OH)D (bound plus free) or the unbound free 25(OH)D the crucial determinant of the non-classical actions of vitamin D? While DBP-bound-25(OH)D is important for renal handling of 25(OH)D and endocrine synthesis of 1,25(OH)2D, how does DBP impact extra-renal synthesis of 1,25(OH)2D and subsequent 1,25(OH)2D actions? Are their pathophysiological contexts where total 25(OH)D and free 25(OH)D would diverge in value as a marker of vitamin D status? This review aims to introduce and discuss the concept of free 25(OH)D, the molecular biology and biochemistry of vitamin D and DBP that provides the context for free 25(OH)D, and surveys in vitro, animal, and human studies taking free 25(OH)D into consideration.
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Affiliation(s)
- Rene F. Chun
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
- *Correspondence: Rene F. Chun
| | - Albert Shieh
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Carter Gottlieb
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Vahe Yacoubian
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Jeffrey Wang
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
| | - Martin Hewison
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, United Kingdom
| | - John S. Adams
- Department of Orthopaedic Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States
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Chapron BD, Chapron A, Phillips B, Okoli MC, Shen DD, Kelly EJ, Himmelfarb J, Thummel KE. Reevaluating the role of megalin in renal vitamin D homeostasis using a human cell-derived microphysiological system. ALTEX-ALTERNATIVES TO ANIMAL EXPERIMENTATION 2018; 35:504-515. [PMID: 29999169 PMCID: PMC6896899 DOI: 10.14573/altex.1803161] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/29/2018] [Indexed: 01/08/2023]
Abstract
The role of megalin in the regulation of renal vitamin D homeostasis has previously been evaluated in megalin-knockout mice and rat proximal tubule epithelial cells. We revisited these hypotheses that were previously tested solely in rodent models, this time using a 3-dimensional proximal tubule microphysiological system incorporating primary human proximal tubule epithelial cells. Using this human cell-derived model, we confirmed that 25OHD3 is transported into the human proximal tubule epithelium via megalin-mediated endocytosis while bound to vitamin D binding protein. Building upon these findings, we then evaluated the role of megalin in modulating the cellular uptake and biological activity of 1α,25(OH)2D3. Inhibition of megalin function decreased the 1α,25(OH)2D3-mediated induction of both cytochrome P450 24A1 protein levels and 24-hydroxylation activity following perfusion with vitamin D binding protein and 1α,25(OH)2D3. The potential for reciprocal effects from 1α,25(OH)2D3 on megalin expression were also tested. Contrary to previously published observations from rat proximal tubule epithelial cells, 1α,25(OH)2D3 did not induce megalin gene expression, thus highlighting the potential for meaningful interspecies differences in the homeostatic regulation of megalin in rodents and humans. These findings challenge a recently promoted hypothesis, predicated on the rodent cell data, that attempts to connect 1α,25(OH)2D3-mediated regulation of renal megalin expression and the pathology of chronic kidney disease in humans. In addition to providing specific insights related to the importance of renal megalin in vitamin D homeostasis, these results constitute a proof-of-concept that human-derived microphysiological systems are a suitable replacement for animal models for quantitative pharmacology and physiology research.
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Affiliation(s)
- Brian D Chapron
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Alenka Chapron
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Brian Phillips
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Miracle C Okoli
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Danny D Shen
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Edward J Kelly
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | | | - Kenneth E Thummel
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
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Tong M, Andreani T, Krotow A, Gundogan F, de la Monte SM. Potential Contributions of the Tobacco Nicotine-Derived Nitrosamine Ketone to White Matter Molecular Pathology in Fetal Alcohol Spectrum Disorder. ACTA ACUST UNITED AC 2016; 3. [PMID: 28868525 PMCID: PMC5575815 DOI: 10.15436/2377-1348.16.729] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Background Fetal alcohol spectrum disorder (FASD) is associated with long-term
deficits in cognitive and motor functions. Previous studies linked
neurodevelopmental abnormalities to increased oxidative stress and white
matter hypotrophy. However, similar effects occur with low-dose nitrosamine
exposures, alcohol abuse correlates with cigarette smoking, and tobacco
smoke contains tobacco-specific nitrosamines, including NNK. Hypothesis Tobacco smoke exposure is a co-factor in FASD. Design Long Evans rat pups were i.p. administered ethanol (2 g/kg) on
postnatal days (P) 2, 4, 6 and/or NNK (2 mg/kg) on P3, P5, and P7 to
simulate third trimester human exposures. Oligodendroglial
myelin-associated, neuroglial, and relevant transcription factor mRNA
transcripts were measured using targeted PCR arrays. Results Ethanol and NNK differentially altered the expression of immature and
mature oligodendroglial, neuronal and astrocytic structural and
plasticity-associated, and various transcription factor genes. NNK’s
effects were broader and more pronounced than ethanol’s, and
additive or synergistic effects of dual exposures impacted expression of all
four categories of genes investigated. Conclusion Developmental exposures to alcohol and NNK (via tobacco smoke)
contribute to sustained abnormalities in brain white matter structure and
function via distinct but overlapping alterations in the expression of genes
that regulate oligodendrocyte survival, maturation and function, neuroglial
structural integrity, and synaptic plasticity. The results support the
hypothesis that smoking may contribute to brain abnormalities associated
with FASD.
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Affiliation(s)
- Ming Tong
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center Rhode Island Hospital, Providence, RI.,Warren Alpert Medical School of Brown University, Providence, RI
| | - Tomas Andreani
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center Rhode Island Hospital, Providence, RI
| | | | - Fusun Gundogan
- Warren Alpert Medical School of Brown University, Providence, RI.,Department of Pathology, Women and Infants Hospital of Rhode Island, Providence, RI
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center Rhode Island Hospital, Providence, RI.,Warren Alpert Medical School of Brown University, Providence, RI.,Pathobiology Graduate Program, Brown University, Providence, RI.,Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI
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7
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Molina MN, Ferder L, Manucha W. Emerging Role of Nitric Oxide and Heat Shock Proteins in Insulin Resistance. Curr Hypertens Rep 2015; 18:1. [DOI: 10.1007/s11906-015-0615-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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8
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Mazzei L, Docherty NG, Manucha W. Mediators and mechanisms of heat shock protein 70 based cytoprotection in obstructive nephropathy. Cell Stress Chaperones 2015; 20:893-906. [PMID: 26228633 PMCID: PMC4595437 DOI: 10.1007/s12192-015-0622-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/24/2015] [Accepted: 07/09/2015] [Indexed: 12/19/2022] Open
Abstract
Urinary heat shock protein 70 (Hsp70) is rapidly increased in patients with clinical acute kidney injury, indicating that it constitutes a component of the endogenous stress response to renal injury. Moreover, experimental models have demonstrated that Hsp70 activation is associated with the cytoprotective actions of several drugs following obstruction, including nitric oxide (NO) donors, geranylgeranylacetone, vitamin D, and rosuvastatin. Discrete and synergistic effects of the biological activities of Hsp70 may explain its cytoprotective role in obstructive nephropathy. Basic studies point to a combination of effects including inhibition of apoptosis and inflammation, repair of damaged proteins, prevention of unfolded protein aggregation, targeting of damaged protein for degradation, and cytoskeletal stabilization as primary effectors of Hsp70 action. This review summarizes our understanding of how the biological actions of Hsp70 may affect renal cytoprotection in the context of obstructive injury. The potential of Hsp70 to be of central importance to the mechanism of action of various drugs that modify the genesis of experimental obstructive nephropathy is considered.
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Affiliation(s)
- Luciana Mazzei
- Área de Farmacología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina.
- IMBECU-CONICET (National Council of Scientific and Technical Research of Argentina), Buenos Aires, Argentina.
| | - Neil G Docherty
- Conway Institute of Biomolecular and Biomedical Research, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Walter Manucha
- Área de Farmacología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- IMBECU-CONICET (National Council of Scientific and Technical Research of Argentina), Buenos Aires, Argentina
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9
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Tong M, Yu R, Silbermann E, Zabala V, Deochand C, de la Monte SM. Differential Contributions of Alcohol and Nicotine-Derived Nitrosamine Ketone (NNK) to White Matter Pathology in the Adolescent Rat Brain. Alcohol Alcohol 2015; 50:680-9. [PMID: 26373813 DOI: 10.1093/alcalc/agv102] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 08/17/2015] [Indexed: 12/30/2022] Open
Abstract
AIM Epidemiologic studies have demonstrated high rates of smoking among alcoholics, and neuroimaging studies have detected white matter atrophy and degeneration in both smokers and individuals with alcohol-related brain disease (ARBD). These findings suggest that tobacco smoke exposure may be a co-factor in ARBD. The present study examines the differential and additive effects of tobacco-specific nitrosamine (NNK) and ethanol exposures on the structural and functional integrity of white matter in an experimental model. METHODS Adolescent Long Evans rats were fed liquid diets containing 0 or 26% ethanol for 8 weeks. In weeks 3-8, rats were treated with nicotine-derived nitrosamine ketone (NNK) (2 mg/kg, 3×/week) or saline by i.p. injection. In weeks 7-8, the ethanol group was binge-administered ethanol (2 g/kg; 3×/week). RESULTS Ethanol, NNK and ethanol + NNK caused striking degenerative abnormalities in white matter myelin and axons, with accompanying reductions in myelin-associated glycoprotein expression. Quantitative RT-PCR targeted array and heatmap analyses demonstrated that ethanol modestly increased, whereas ethanol + NNK sharply increased expression of immature and mature oligodendroglial genes, and that NNK increased immature but inhibited mature oligodendroglial genes. In addition, NNK modulated expression of neuroglial genes in favor of growth cone collapse and synaptic disconnection. Ethanol- and NNK-associated increases in FOXO1, FOXO4 and NKX2-2 transcription factor gene expression could reflect compensatory responses to brain insulin resistance in this model. CONCLUSION Alcohol and tobacco exposures promote ARBD by impairing myelin synthesis, maturation and integrity via distinct but overlapping mechanisms. Public health measures to reduce ARBD should target both alcohol and tobacco abuses.
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Affiliation(s)
- Ming Tong
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Rosa Yu
- Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
| | | | - Valerie Zabala
- Molecular Pharmacology and Physiology Graduate Program, Brown University, Providence, RI, USA
| | - Chetram Deochand
- Biotechnology Graduate Program, Brown University, Providence, RI, USA
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
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10
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Ziegler TE, Kapoor A, Hedman CJ, Binkley N, Kemnitz JW. Measurement of 25-hydroxyvitamin D(2&3) and 1,25-dihydroxyvitamin D(2&3) by tandem mass spectrometry: A primate multispecies comparison. Am J Primatol 2015; 77:801-10. [PMID: 25845705 PMCID: PMC4481142 DOI: 10.1002/ajp.22403] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/13/2014] [Accepted: 03/01/2015] [Indexed: 11/09/2022]
Abstract
Vitamin D metabolites are widely studied for their roles in bone health, immune functions, and other potential physiologic roles in humans. However, the optimal blood levels of vitamin D metabolites are still unclear. Various methods for measuring vitamin D metabolites have been used and recently liquid chromatography tandem mass spectroscopy (LC-MS/MS) has been adopted as the gold standard for vitamin D metabolite measurement. Here, we report the use of LC-MS/MS to measure 25-hydroxyvitamin D (25(OH)D(2&3)), and 1,25-dihydroxyvitamin D (1,25(OH)2D(2&3)), in three laboratory nonhuman primate species: common marmoset (Callithrix jacchus), rhesus macaque (Macaca mulatta), and cynomolgus macaque (Macaca fascicularis), and compare them to humans using the same technique. The nonhuman primates showed blood levels for 25(OH)D3 and 1,25(OH)2D3 significantly higher than human values with marmosets having the highest levels. Marmoset samples showed significantly more variability among individuals than those from macaques for both metabolites, but all three nonhuman primate species exhibited large variation within species for both 25(OH)D(2&3) and 1,25(OH)2D(2&3). Marmoset females had significantly lower values than the males for 25(OH)D3, while rhesus males showed a significant decrease in 25(OH)D3 with age. The most striking finding is the variation within species for vitamin D levels even in laboratory primates that have a controlled diet, UV exposure, and in some cases, genetic constraints. Similar variation in 25(OH)D responses to a fixed dose of oral vitamin D supplementation has been reported in humans. We suggest that these species can provide primate models for examining the factors influencing variation in the levels of vitamin D necessary for human and nonhuman primate health.
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Affiliation(s)
- Toni E Ziegler
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Institute of Clinical and Translational Research, University of Wisconsin, Madison, Wisconsin
| | - Amita Kapoor
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Institute of Clinical and Translational Research, University of Wisconsin, Madison, Wisconsin
| | - Curtis J Hedman
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Institute of Clinical and Translational Research, University of Wisconsin, Madison, Wisconsin
- Wisconsin State Laboratory of Hygiene, University of Wisconsin, Madison, Wisconsin
| | - Neil Binkley
- Department of Medicine, University of Wisconsin, Madison, Wisconsin
| | - Joseph W Kemnitz
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin
- Institute of Clinical and Translational Research, University of Wisconsin, Madison, Wisconsin
- Department of Cell and Regenerative Biology, University of Wisconsin, Madison, Wisconsin
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11
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Zhou R, Chun RF, Lisse TS, Garcia AJ, Xu J, Adams JS, Hewison M. Vitamin D and alternative splicing of RNA. J Steroid Biochem Mol Biol 2015; 148:310-7. [PMID: 25447737 PMCID: PMC4361308 DOI: 10.1016/j.jsbmb.2014.09.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 09/23/2014] [Accepted: 09/26/2014] [Indexed: 02/07/2023]
Abstract
The active form of vitamin D (1α,25-dihydroxyvitamin D, 1,25(OH)2D) exerts its genomic effects via binding to a nuclear high-affinity vitamin D receptor (VDR). Recent deep sequencing analysis of VDR binding locations across the complete genome has significantly expanded our understanding of the actions of vitamin D and VDR on gene transcription. However, these studies have also promoted appreciation of the extra-transcriptional impact of vitamin D on gene expression. It is now clear that vitamin D interacts with the epigenome via effects on DNA methylation, histone acetylation, and microRNA generation to maintain normal biological functions. There is also increasing evidence that vitamin D can influence pre-mRNA constitutive splicing and alternative splicing, although the mechanism for this remains unclear. Pre-mRNA splicing has long been thought to be a post-transcription RNA processing event, but current data indicate that this occurs co-transcriptionally. Several steroid hormones have been recognized to coordinately control gene transcription and pre-mRNA splicing through the recruitment of nuclear receptor co-regulators that can both control gene transcription and splicing. The current review will discuss this concept with specific reference to vitamin D, and the potential role of heterogeneous nuclear ribonucleoprotein C (hnRNPC), a nuclear factor with an established function in RNA splicing. hnRNPC, has been shown to be involved in the VDR transcriptional complex as a vitamin D-response element-binding protein (VDRE-BP), and may act as a coupling factor linking VDR-directed gene transcription with RNA splicing. In this way hnRNPC may provide an additional mechanism for the fine-tuning of vitamin D-regulated target gene expression. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.
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Affiliation(s)
- Rui Zhou
- UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery, Orthopaedic Hospital, University of California at Los Angeles, Los Angeles, CA 90095, USA; Department of Orthopaedics, the Orthopedic Surgery Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
| | - Rene F Chun
- UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery, Orthopaedic Hospital, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Thomas S Lisse
- Mount Desert Island Biological Laboratory, 159 Old Bar Harbor Road, Salisbury Cove, ME 04672, USA
| | - Alejandro J Garcia
- UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery, Orthopaedic Hospital, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Jianzhong Xu
- Department of Orthopaedics, the Orthopedic Surgery Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing 400038, China
| | - John S Adams
- UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery, Orthopaedic Hospital, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Martin Hewison
- UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery, Orthopaedic Hospital, University of California at Los Angeles, Los Angeles, CA 90095, USA.
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12
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The heterodimeric structure of heterogeneous nuclear ribonucleoprotein C1/C2 dictates 1,25-dihydroxyvitamin D-directed transcriptional events in osteoblasts. Bone Res 2014; 2. [PMID: 25506471 PMCID: PMC4261231 DOI: 10.1038/boneres.2014.11] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Heterogeneous nuclear ribonucleoprotein (hnRNP) C plays a key role in RNA processing but also exerts a dominant negative effect on responses to 1,25-dihydroxyvitamin D (1,25(OH)2D) by functioning as a vitamin D response element-binding protein (VDRE-BP). hnRNPC acts a tetramer of hnRNPC1 (huC1) and hnRNPC2 (huC2), and organization of these subunits is critical to in vivo nucleic acid-binding. Overexpression of either huC1 or huC2 in human osteoblasts is sufficient to confer VDRE-BP suppression of 1,25(OH)2D-mediated transcription. However, huC1 or huC2 alone did not suppress 1,25(OH)2D-induced transcription in mouse osteoblastic cells. By contrast, overexpression of huC1 and huC2 in combination or transfection with a bone-specific polycistronic vector using a “self-cleaving” 2A peptide to co-express huC1/C2 suppressed 1,25D-mediated induction of osteoblast target gene expression. Structural diversity of hnRNPC between human/NWPs and mouse/rat/rabbit/dog was investigated by analysis of sequence variations within the hnRNP CLZ domain. The predicted loss of distal helical function in hnRNPC from lower species provides an explanation for the altered interaction between huC1/C2 and their mouse counterparts. These data provide new evidence of a role for hnRNPC1/C2 in 1,25(OH)2D-driven gene expression, and further suggest that species-specific tetramerization is a crucial determinant of its actions as a regulator of VDR-directed transactivation.
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13
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García IM, Altamirano L, Mazzei L, Fornés M, Cuello-Carrión FD, Ferder L, Manucha W. Vitamin D receptor-modulated Hsp70/AT1 expression may protect the kidneys of SHRs at the structural and functional levels. Cell Stress Chaperones 2014; 19:479-91. [PMID: 24222043 PMCID: PMC4041946 DOI: 10.1007/s12192-013-0474-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 10/22/2013] [Accepted: 10/24/2013] [Indexed: 02/07/2023] Open
Abstract
Previous hypertension studies have shown that low levels of vitamin D are linked to elevated renin-angiotensin system. The heat shock protein 70 regulates signaling pathways for cellular oxidative stress responses. Hsp70 has been shown to protect against angiotensin II-induced hypertension and exert a cytoprotective effect. Here, we wanted to evaluate whether the vitamin D receptor (VDR) associated with Hsp70/AT1 expression may be involved in the mechanism by which paricalcitol provides renal protection in spontaneously hypertensive rats (SHRs). One-month-old female SHRs were treated for 4 months with vehicle, paricalcitol, enalapril, or a combination of both paricalcitol and enalapril. The following were determined: blood pressure; biochemical parameters; fibrosis; apoptosis; mitochondrial morphology; and VDR, AT1 receptor, and Hsp70 expression in the renal cortex. Blood pressure was markedly reduced by enalapril or the combination but not by paricalcitol alone. However, VDR activation, enalapril or combination, prevented fibrosis, the number of TUNEL-positive apoptotic cells, mitochondrial damage, and NADPH oxidase activity in SHRs. Additionally, high AT1 receptor expression, like low Hsp70 expression (immunohistochemical/immunofluorescence studies), was reversed in the renal cortices of paricalcitol- and/or enalapril-treated animals (SHRs), and these changes were most marked in the combination therapy group. Finally, all of the recovery parameters were consistent with an improvement in VDR expression. Data suggest that Hsp70/AT1 modulated by VDR is involved in the mechanism by which paricalcitol provides renal protection in SHRs. We propose that low AT1 expression through VDR induction could be a consequence of the heat shock response Hsp70-mediated cell protection.
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Affiliation(s)
- Isabel Mercedes García
- />Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- />Área de Farmacología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- />Departamento de Bioquímica y Ciencias Biológicas, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
| | - Liliana Altamirano
- />Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- />Área de Farmacología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Luciana Mazzei
- />Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- />IMBECU-CONICET (National Council of Scientific and Technical Research of Argentina), Buenos Aires, Argentina
| | - Miguel Fornés
- />IHEM-CONICET (National Council of Scientific and Technical Research of Argentina), Buenos Aires, Argentina
| | | | - León Ferder
- />Department of Physiology and Pharmacology, Ponce School of Medicine and Health Sciences, Ponce, Puerto Rico
| | - Walter Manucha
- />Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- />IMBECU-CONICET (National Council of Scientific and Technical Research of Argentina), Buenos Aires, Argentina
- />Área de Fisiología Patológica, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo Centro Universitario, Mendoza, 5500 Argentina
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14
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Smith SY, Doyle N, Boyer M, Chouinard L, Saito H. Eldecalcitol, a vitamin D analog, reduces bone turnover and increases trabecular and cortical bone mass, density, and strength in ovariectomized cynomolgus monkeys. Bone 2013; 57:116-22. [PMID: 23774444 DOI: 10.1016/j.bone.2013.06.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 05/24/2013] [Accepted: 06/07/2013] [Indexed: 10/26/2022]
Abstract
Vitamin D insufficiency is common in elderly people worldwide, and intake of supplementary calcium and vitamin D is recommended to those with a high risk of fracture. Several clinical studies and meta-analyses have shown that calcium and vitamin D supplementation reduces osteoporotic fractures, and a strong correlation exists between vitamin D status and fracture risk. Vitamin D supplementations improve calcium balance in the body; however, it remains unclear whether vitamin D directly affects bone metabolism. Recently, eldecalcitol (ELD), an active form of vitamin D analog, has been approved for the treatment of osteoporosis in Japan. A 3-year clinical trial showed ELD treatment increased lumbar spine bone mineral density (BMD) and reduced fracture risk in patients with osteoporosis. To evaluate the mechanism of ELD action in bone remodeling, ovariectomized cynomolgus monkeys were treated with 0.1 or 0.3μg/day of ELD for 6months. This treatment increased lumbar BMD by 4.4% and 10.2%, respectively, and suppressed ovariectomy-induced increases in bone turnover markers compared to OVX-vehicle control. Histomorphometric analysis of bone revealed that both bone formation parameters and bone resorption parameters in the trabecular bone of the lumbar vertebrae were suppressed by ELD treatment. ELD treatment also improved biomechanical properties of the lumbar vertebrae and the femoral neck in the ovariectomized cynomolgus monkeys. These results indicate that, in a bone-remodeling animal model, ELD increases BMD and improves bone biomechanical properties by normalizing bone turnover. Therefore, ELD has a direct and potentially beneficial effect on bone metabolism.
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Affiliation(s)
- Susan Y Smith
- Bone Research, Charles River Laboratories Preclinical Services Montreal, Senneville, Quebec H9X 3R3, Canada
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15
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Teixeira DS, Nobrega YKM, Valencia CEU, Gandolfi L, Pratesi R, Castro LCG. Evaluation of 25-hydroxy-vitamin D and parathyroid hormone in Callithrix penicillata primates living in their natural habitat in Brazil. J Med Primatol 2012; 41:364-71. [PMID: 23078575 DOI: 10.1111/jmp.12021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2012] [Indexed: 01/15/2023]
Abstract
BACKGROUND Vitamin D is a secosteroid hormone with important roles in the control of bone and mineral metabolism of vertebrates and in the maintenance of systemic homeostasis. This study aimed (i) to evaluate the serum concentrations of 25-hydroxy-vitamin D levels [25(OH)D], parathyroid hormone (PTH) and ionized calcium (iCa) of wild Callithrix penicillata (black-tufted marmosets) and (ii) to propose reference ranges for those analytes for free-living marmosets. METHODS Blood samples were collected from 15 wild animals and analyzed for 25(OH)D, PTH and iCa. Reference values were calculated following standard analytical criteria. RESULTS The observed mean serum levels (±standard deviation) were 25(OH)D, 61.7 (±20.8) ng/ml; PTH, 275.2 (±34.1) pg/ml; iCai 4.0 (±0.6) mg/dl. CONCLUSIONS For free-living marmosets, the proposed physiological range for 25(OH)D is 20.1-103.3 ng/ml and for PTH is 207.0-343.3 pg/dl, with a confidence interval of 95%.
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16
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Antico A, Tozzoli R, Giavarina D, Tonutti E, Bizzaro N. Hypovitaminosis D as predisposing factor for atrophic type A gastritis: a case-control study and review of the literature on the interaction of Vitamin D with the immune system. Clin Rev Allergy Immunol 2012; 42:355-64. [PMID: 21286859 DOI: 10.1007/s12016-011-8255-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
1,25-Dihydroxyvitamin D displays immunoregulatory and anti-inflammatory properties, and the cells involved in innate and adaptive immune response express the vitamin D receptor and can both produce and respond to this hormone. This article aims at describing the complex immune regulatory role of vitamin D and depicting whether a correlation exists between atrophic type A gastritis and hypovitaminosis. We studied 62 autoimmune gastritis (AIG) patients and compared them to 54 lymphocytic gastritis patients, 21 Helicobacter pylori gastritis patients and 212 healthy subjects. We also statistically analyzed vitamin D concentration in 36,384 outpatients referred to our clinical laboratories. 25-Hydroxyvitamin D levels, the measurable metabolite used to determine vitamin D status in plasma, were measured by a chemiluminescent method. Average level of 25-OHD in AIG subjects was 9.8 ± 5.6 ng/mL (95% confidence interval (CI) 8.4-11.2), 11.1 ± 8.4 (CI 7.5-14.7) in H. pylori gastritis patients, 22.2 ± 13.5 (CI 18.6-25.8) in nonspecific lymphocytic gastritis patients, 21.3 ± 12.2 (CI 19.7-22.9) in healthy subjects, and 21.8 ± 13.1 (CI 21.7-21.9) in the 36,384 outpatients. Vitamin D levels in AIG patients were significantly lower than in patients with nonspecific gastritis or in the general population, supporting the hypothesis that hypovitaminosis D might be a risk factor for the development of autoimmune diseases. The low vitamin D concentration in H. pylori gastritis patients might act as predisposing factor for a more severe Th1-type aggression to the stomach epithelium.
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Affiliation(s)
- Antonio Antico
- Department of Clinical Pathology, Cittadella General Hospital, Cittadella, Italy
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17
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Higa GM, Hicks J, Isabella C. Adjudication of the alleged role of vitamin d in the antimicrobial pathway. SCIENTIFICA 2012; 2012:129516. [PMID: 24278668 PMCID: PMC3820478 DOI: 10.6064/2012/129516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 06/13/2012] [Indexed: 06/02/2023]
Abstract
Dynamic interactions between microorganism and host have evolved in such a way that while microbial pathogens are the cause of many human infections, a symbiotic relationship is also known to exist. Another important anomaly is that exposure to pathogenic organisms does not necessarily result in development of clinical disease. The latter conclusion infers that susceptibility to infectious disease can be modified by host-related factors. Arguably the two most prominent factors are genetic variability and immunologic status of the exposed individual. Because of the Human Genome and the HapMap projects, developments in genotyping technology have brought the possibility of identifying associations between specific genetic alterations and common diseases closer to reality. In addition, a growing body of evidence suggests vitamin D has an important contributory role in the antimicrobial pathway.
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Affiliation(s)
- Gerald M. Higa
- Schools of Pharmacy and Medicine and the Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, WV 26506, USA
| | - Jason Hicks
- School of Pharmacy, West Virginia University, Morgantown, WV 26506, USA
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18
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Casteleyn C, Bakker J, Breugelmans S, Kondova I, Saunders J, Langermans JAM, Cornillie P, Van den Broeck W, Van Loo D, Van Hoorebeke L, Bosseler L, Chiers K, Decostere A. Anatomical description and morphometry of the skeleton of the common marmoset (Callithrix jacchus). Lab Anim 2012; 46:152-63. [DOI: 10.1258/la.2012.011167] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Callithrix jacchus (common marmoset) is regularly used in biomedical research, including for studies involving the skeleton. To support these studies, skeletons of healthy animals that had been euthanized for reasons not interfering with skeletal anatomy were prepared. The marmoset dental formula 2I-1C-3P-2M of each oral quadrant is atypical for New World monkeys which commonly possess a third molar. Seven cervical, 12–13 thoracic, 7–6 lumbar, 2–3 sacral and 26–29 caudal vertebrae are present, the thoracolumbar region always comprising 19 vertebrae. A sigmoid clavicle connects the scapula with the manubrium of the sternum. Depending on the number of thoracic vertebrae, 4–5 sternebrae are located between the manubrium and xiphoid process. Wide interosseous spaces separate the radius from the ulna, and the tibia from the fibula. A small sesamoid bone is inserted in the m. abductor digiti primi longus at the medial border of the carpus, a pair of ovoid sesamoid bones is located at the palmar/plantar sides of the trochleae of each metapodial bone, and round fabellae articulate with the proximal surfaces of the femoral condyles. Male marmosets possess a small penile bone. Both the front and hind feet have five digits. The hallux possesses a flat nail, whereas all other digits present curved claws. Interestingly, a central bone is present in both the carpus and tarsus. This study provides a description and detailed illustrations of the skeleton of the common marmoset as an anatomical guide for further biomedical research.
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Affiliation(s)
- C Casteleyn
- Applied Veterinary Morphology, Department of Veterinary Sciences, Faculty of Pharmaceutical, Biochemical and Veterinary Sciences, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - J Bakker
- Animal Science Department, Biomedical Primate Research Centre, 2288 GJ Rijswijk, The Netherlands
| | - S Breugelmans
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - I Kondova
- Animal Science Department, Biomedical Primate Research Centre, 2288 GJ Rijswijk, The Netherlands
| | - J Saunders
- Department of Veterinary Medical Imaging and Small Animal Orthopaedics, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - J A M Langermans
- Animal Science Department, Biomedical Primate Research Centre, 2288 GJ Rijswijk, The Netherlands
| | - P Cornillie
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - W Van den Broeck
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - D Van Loo
- Department of Soil Management, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
- UGCT – Department of Physics and Astronomy, Ghent University, 9000 Ghent, Belgium
| | - L Van Hoorebeke
- UGCT – Department of Physics and Astronomy, Ghent University, 9000 Ghent, Belgium
| | - L Bosseler
- Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - K Chiers
- Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - A Decostere
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
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19
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McMillan A, Hicks J, Isabella C, Higa GM. A critical analysis of the (near) legendary status of vitamin D. Expert Rev Endocrinol Metab 2012; 7:103-119. [PMID: 30736115 DOI: 10.1586/eem.11.81] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Labels such as food constituent, nutrient and supplement do not convey a sense of being essential. Yet these rather mundane descriptors, even if correct, belie the true significance of vitamin D. Long believed to be merely a functioning cofactor akin to vitamin C, deficiency of this secosteroid hormone is clearly associated with morbid complications of calcium and bone mineral metabolism, and because the hormonal effects are mediated by nuclear receptors that regulate the expression of many subordinate genes, the vitamin's pleiotropic mode of action can influence numerous metabolic pathways and, possibly, a number of different diseases. Although the vitamin is under intensive investigation, much still remains unknown, even in bone health, as the identity of osteoporosis susceptibility genes remains uncertain. This article focuses on various aspects of the basic science and molecular biology of the vitamin D endocrine system. The primary goal is to critically examine the evidence supporting its role in bone metabolism, diabetes and cancer.
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Affiliation(s)
- Ashlee McMillan
- a School of Pharmacy, West Virginia University, Morgantown, WV 26506, USA
| | - Jason Hicks
- a School of Pharmacy, West Virginia University, Morgantown, WV 26506, USA
| | | | - Gerald M Higa
- b Schools of Pharmacy and Medicine and the Mary Babb Randolph Cancer Center, West Virginia University, Morgantown, WV 26506, USA.
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20
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Lisse TS, Hewison M, Adams JS. Hormone response element binding proteins: novel regulators of vitamin D and estrogen signaling. Steroids 2011; 76:331-9. [PMID: 21236284 PMCID: PMC3042887 DOI: 10.1016/j.steroids.2011.01.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 01/04/2011] [Accepted: 01/05/2011] [Indexed: 01/11/2023]
Abstract
Insights from vitamin D-resistant New World primates and their human homologues as models of natural and pathological insensitivity to sterol/steroid action have uncovered a family of novel intracellular vitamin D and estrogen regulatory proteins involved in hormone action. The proteins, known as "vitamin D or estrogen response element-binding proteins", behave as potent cis-acting, transdominant regulators to inhibit steroid receptor binding to DNA response elements and is responsible for vitamin D and estrogen resistances. This set of interactors belongs to the heterogeneous nuclear ribonucleoprotein (hnRNP) family of previously known pre-mRNA-interacting proteins. This review provides new insights into the mechanism by which these novel regulators of signaling and metabolism can act to regulate responses to vitamin D and estrogen. In addition the review also describes other molecules that are known to influence nuclear receptor signaling through interaction with hormone response elements.
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Affiliation(s)
- Thomas S Lisse
- Department of Orthopaedic Surgery and Molecular Biology Institute, David Geffen School of Medicine at UCLA, 615 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
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21
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Fernandes de Abreu DA, Ibrahim EC, Boucraut J, Khrestchatisky M, Féron F. Severity of experimental autoimmune encephalomyelitis is unexpectedly reduced in mice born to vitamin D-deficient mothers. J Steroid Biochem Mol Biol 2010; 121:250-3. [PMID: 20214984 DOI: 10.1016/j.jsbmb.2010.03.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 02/02/2010] [Accepted: 03/01/2010] [Indexed: 11/23/2022]
Abstract
Accumulating data indicate that vitamin D, a sun-induced hormone, plays a key role in multiple sclerosis (MS) etiology. Notably, it has been shown that there is a remarkable season of birth effect in MS. We surmised that gestational vitamin D deficiency is a risk factor for MS. To test this hypothesis, a vitamin D deficiency was induced in C57BL/6 female mice 6 weeks prior to conception and prolonged until offspring birth. Contrary to our prediction, we show here that adult offspring exposed to developmental vitamin D deficiency (DVD) developed a striking milder and delayed experimental autoimmune encephalomyelitis (EAE), when compared to control offspring. Using reverse transcription and quantitative real-time PCR, we measured the expression level of 22 candidate transcripts in the spleen, the cerebrum and the spinal cord, at Day0 and Day30 post-immunization. We report here that, at Day30 post-immunization, TNF, osteopontin, H2-Eb were over-expressed and IFN was under-expressed in the spinal cord of control mice and not in DVD mice. Another discrepancy between nervous and immune systems was observed: expression of IL4 was dysregulated exclusively in the spleen. Reduced symptom severity in DVD mice can partially be explained by a nervous system-restricted over-expression of vitamin D receptor (VDR), two heat shock proteins (HSP90, HSPa8) and FK506 binding protein 1a (FKBP1a), at Day0. Our clinical test and molecular findings converge to indicate that maternal hypovitaminosis D imprints the foetus and alters the susceptibility of the offspring to EAE. We propose a new hypothesis to explain our unexpected observations.
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22
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Chen H, Clemens TL, Hewison M, Adams JS. Estradiol and tamoxifen mediate rescue of the dominant-negative effects of estrogen response element-binding protein in vivo and in vitro. Endocrinology 2009; 150:2429-35. [PMID: 19106221 PMCID: PMC2671906 DOI: 10.1210/en.2008-1148] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Biological responses to estrogens are dependent on the integrated actions of proteins, including the estrogen receptor (ER)-alpha, that regulate the transcription of estrogen response element (ERE)-containing target genes. We have identified a naturally occurring ERE antagonist, termed an ERE-binding protein (BP). To verify that ERE-BP can induce estradiol (E(2)) resistance in vivo, we generated transgenic mice that overexpress this protein in breast tissue. Female transgenic mice with high levels of ERE-BP were unable to lactate, and we hypothesized that this effect was dependent on the relative levels of ERE-BP and ERalpha ligand. To test this hypothesis, wild-type and ERE-BP-expressing female mice were implanted with capsules containing E(2), the selective estrogen receptor modulator tamoxifen, or placebo. Histological analysis of nonlactating mammary glands showed a 4.5-fold increase in gland branch number and 3.7-fold increase in ducts in ERE-BP mice treated with E(2) (7.5 mg, 21 d) compared with placebo-treated ERE-BP mice. Wild-type mice showed a 5.3-fold increase in branches and 1.4-fold increase in ducts under the same conditions. Similar results were obtained with tissue from lactating mice, in which tamoxifen also increased mammary gland branch number. Studies using ERE-BP-expressing MCF-7 breast cells showed that high doses of E(2) (1000 nM) restored normal ERalpha-chromatin interaction in these cells, whereas tamoxifen was able to achieve this effect at a dose of 10 nM. These data highlight the importance of ERE-BP as an attenuator of normal ERalpha signaling in vivo and further suggest that ERE-BP is a novel target for modulation by selective estrogen receptor modulators.
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MESH Headings
- Animals
- Estradiol/blood
- Estradiol/pharmacology
- Estrogen Receptor alpha/antagonists & inhibitors
- Estrogen Receptor alpha/metabolism
- Estrogen Receptor alpha/physiology
- Female
- Genes, Dominant/drug effects
- Genes, Dominant/physiology
- Humans
- Mammary Glands, Animal/anatomy & histology
- Mammary Glands, Animal/drug effects
- Mammary Glands, Animal/metabolism
- Matrix Attachment Region Binding Proteins/antagonists & inhibitors
- Matrix Attachment Region Binding Proteins/genetics
- Matrix Attachment Region Binding Proteins/metabolism
- Matrix Attachment Region Binding Proteins/physiology
- Mice
- Mice, Transgenic
- Nuclear Matrix-Associated Proteins/antagonists & inhibitors
- Nuclear Matrix-Associated Proteins/genetics
- Nuclear Matrix-Associated Proteins/metabolism
- Nuclear Matrix-Associated Proteins/physiology
- Receptors, Estrogen/antagonists & inhibitors
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Receptors, Estrogen/physiology
- Selective Estrogen Receptor Modulators/pharmacology
- Tamoxifen/pharmacology
- Tumor Cells, Cultured
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Affiliation(s)
- Hong Chen
- Division of Endocrinology, Metabolism, and Lipids, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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23
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Abstract
Vitamin D has pleiotropic effects that go beyond its traditional role in calcium homeostasis. Hundreds of genes with vitamin D receptor response elements directly or indirectly influence cell cycling and proliferation, differentiation, and apoptosis. Vitamin D compounds also have effects on cell function that are nongenomic. The noncalcemic actions of vitamin D influence normal and pathological cell growth, carcinogenesis, immune function, and cardiovascular physiology. This review examines many of the various mechanisms by which vitamin D alters cellular growth and differentiation and explores cell-specific factors that influence responsiveness to vitamin D.
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Affiliation(s)
- Sam Samuel
- The Western New York Veterans Administration Medical Center, University at Buffalo, State University of New York, Buffalo, New York 14215, USA
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24
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Baroni E, Camisa B, D'Ambrosio D. Inter-species differences in sensitivity to the calcemic activity of the novel 1,25-dihydroxyvitamin D3 analog BXL746. Regul Toxicol Pharmacol 2008; 52:332-41. [PMID: 18854204 DOI: 10.1016/j.yrtph.2008.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 09/08/2008] [Accepted: 09/13/2008] [Indexed: 10/21/2022]
Abstract
The activities of 1,25-dihydroxyvitamin D3 and its synthetic analogs have been extensively studied in humans as well as in preclinical species, and recent data show potential therapeutic utility in cancer treatment. However, their chronic administration leads to changes in blood mineral ion concentrations, and at high doses can result in symptomatic hypercalcemia limiting therapeutic applicability. To overcome this issue, a therapeutic approach based on administration of intermittent, high doses of 1,25(OH)2D3 has been explored in prostate cancer patients. Despite these and other investigations, limited information is available on the effects of acute systemic administration of high doses of 1,25(OH)2D3 or its analogs. Here, we report a comparative analysis of the pro-calcemic effects of the novel 1,25(OH)2D3 analog BXL746 following acute or chronic administration in animals and humans. While chronic administration of BXL746 to rats, dogs and humans leads to similar modulation of calcemia in these species, single dose administration reveals >1000-fold higher sensitivity of dog compared to rat and human in induction of hypercalcemia and consequent systemic toxicity. Our data indicate that the rat is a more relevant species than the dog for the prediction of human results when acute administration of a 1,25(OH)2D3 analog is envisaged.
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Affiliation(s)
- Enrico Baroni
- BioXell SpA, Department of Preclinical Development, Via Olgettina, 58, Milano 20132, Italy.
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25
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Abstract
Our perception of the vitamin D system continues to evolve. Recent studies have re-evaluated the parameters for adequate vitamin D status in humans, revealing a high prevalence of insufficiency in many populations throughout the world. Other reports have highlighted the potential consequences of vitamin D insufficiency beyond established effects on bone homeostasis. Most notably, there is now strong evidence of a role for vitamin D in modulating innate and adaptive immunities, with insufficiency being linked to infectious disease and other immune disorders. To date, signaling pathways for these new responses to vitamin D have been based on established endocrine models for active 1,25-dihydroxyvitamin D, despite present evidence for more localized, intracrine modes of action. In the following review, we provide a fresh perspective on vitamin D signaling in non-classical target cells such as macrophages by highlighting novel factors associated with the transport and action of this pluripotent secosteroid.
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Affiliation(s)
- Rene F Chun
- Department of Orthopaedic Surgery, David Geffen School of Medicine, UCLA, 615 Charles E Young Drive South, Los Angeles, California 90095, USA
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26
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Abstract
The identification of endogenous sterol derivatives that modulate the Hedgehog (Hh) signalling pathway has begun to suggest testable hypotheses for the cellular biological functions of Patched, and for the lipoprotein association of Hh. Progress in the field of intracellular sterol trafficking has emphasized how tightly the distribution of intracellular sterol is controlled, and suggests that the synthesis of sterol derivatives can be influenced by specific sterol-delivery pathways. The combination of this field with Hh studies will rapidly give us a more sophisticated understanding of both the Hh signal-transduction pathway and the cell biology of sterol metabolism.
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Affiliation(s)
- Suzanne Eaton
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany.
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27
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Heat shock protein 90beta: a novel mediator of vitamin D action. Biochem Biophys Res Commun 2008; 367:578-83. [PMID: 18182164 DOI: 10.1016/j.bbrc.2007.12.179] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Accepted: 12/30/2007] [Indexed: 12/30/2022]
Abstract
We investigated the role of Heat shock protein 90 (Hsp90) in vitamin D action in Caco-2 cells using geldanamycin (GA) to block Hsp90 function and RNA interference to reduce Hsp90beta expression. When cells were exposed to GA, vitamin D-mediated gene expression and transcriptional activity were inhibited by 69% and 54%, respectively. Gel shift analysis indicated that GA reduced vitamin D-mediated DNA binding activity of the vitamin D receptor (VDR). We tested the specific role of Hsp90beta by knocking down its expression with stably expressed short hairpin RNA. Vitamin D-induced gene expression and transcriptional activity were reduced by 90% and 80%, respectively, in Hsp90beta-deficient cells. Nuclear protein for VDR and RXRalpha, its heterodimer partner, were not reduced in Hsp90beta-deficient cells. These findings indicate that Hsp90beta is needed for optimal vitamin D responsiveness in the enterocyte and demonstrate a specific role for Hsp90beta in VDR signaling.
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28
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Chen H, Hewison M, Adams JS. Control of estradiol-directed gene transactivation by an intracellular estrogen-binding protein and an estrogen response element-binding protein. Mol Endocrinol 2007; 22:559-69. [PMID: 18096692 DOI: 10.1210/me.2007-0297] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
New World primates exhibit a form of resistance to estrogens that is associated with overexpression of an estrogen response element (ERE)-binding protein (ERE-BP) and an intracellular estradiol (E(2))-binding protein (IEBP). Both proteins suppress E(2)-mediated transcription when overexpressed in estrogen receptor-alpha (ERalpha)-positive cells. Although ERE-BP acts as a competitor for ERE occupancy by liganded ERalpha, the function of IEBP and its human homolog, heat-shock protein 27 (hsp27), is less clear. In data presented here, we have used E(2)-responsive human MCF-7 breast cancer cells to show that IEBP/hsp27 can regulate estrogen signaling as a cytosolic decoy for E(2) and as a protein chaperone for ERalpha. Furthermore, co-immunoprecipitation, colocalization, yeast two-hybrid, and glutathione S-transferase pull-down analyses indicate that IEBP/hsp27 also interacts with ERE-BP to form a dynamic complex that appears to cycle between the cytoplasm and nucleus during normal estrogen signaling. Overexpression of either IEBP/hsp27 or ERE-BP in MCF-7 cells resulted in abnormal subcellular distribution of the IEBP/hsp27 and ERE-BP, with concomitant dysregulation of ERE occupancy as determined by chromatin immunoprecipitation. We hypothesize that IEBP/hsp27 and ERE-BP not only cause hormone resistance in New World primates but are also crucial to normal estrogen signaling in human cells. This appears to involve a physical association between the two proteins to form a complex that is able to interact with both E(2) and ERalpha in cytosolic and nuclear compartments.
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Affiliation(s)
- Hong Chen
- Division of Endocrinology, Metabolism, and Lipids, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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29
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Serum Nutritional Profiles of Free-Ranging Alouatta Caraya in Northern Argentina: Lipoproteins; Amino Acids; Vitamins A, D, and E; Carotenoids; and Minerals. INT J PRIMATOL 2007. [DOI: 10.1007/s10764-007-9200-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Chen H, Hewison M, Adams JS. Functional Characterization of Heterogeneous Nuclear Ribonuclear Protein C1/C2 in Vitamin D Resistance. J Biol Chem 2006; 281:39114-20. [PMID: 17071612 DOI: 10.1074/jbc.m608006200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Clinically apparent hereditary vitamin D-resistant rickets (HVDRR) usually results from a loss of function mutation in the vitamin D receptor (VDR). We recently described a human with the classical HVDRR phenotype but normal VDR function. Hormone resistance resulted from constitutive overexpression of heterogeneous nuclear ribonucleoprotein (hnRNP) that competed with a normally functioning VDR-retinoid X receptor (RXR) dimer for binding to the vitamin D response element (VDRE). Here we describe the purification, molecular cloning, and expression of this vitamin D resistance-causing, competitive response element-binding protein (REBiP) hnRNP C1/C2. When overexpressed in vitamin D-responsive cells, cDNAs for both hnRNPC1 and hnRNPC2 inhibited VDR-VDRE-directed transactivation (28 and 43%, respectively; both p < 0.005). By contrast, transient expression of an hnRNP C1/C2 small interfering RNA increased VDR transactivation by 39% (p < 0.005). Chromatin immunoprecipitation of nucleoproteins bound to the transcriptionally active 1,25-dihydroxy vitamin D-driven CYP24 promoter revealed the presence of REBiP in vitamin D-responsive human cells and indicated that the normal pattern of 1,25-dihydroxy vitamin D-initiated cyclical movement of the VDR on and off the VDRE is legislated by competitive, reciprocal occupancy of the VDRE by hnRNP C1/C2. The temporal and reciprocal pattern of VDR and hnRNPC1/C2 interaction with the VDRE was lost in HVDRR cells overexpressing the hnRNP C1/C2 REBiP. These observations provide further evidence for the functional importance of REBiP as a component of the multiprotein complex involved in the regulation of vitamin D-mediated transcription. In particular, chromatin immunoprecipitation data suggest that, in addition to its RNA-processing functions, hnRNP C1/C2 may be a key determinant of the temporal patterns of VDRE occupancy.
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Affiliation(s)
- Hong Chen
- Division of Endocrinology, Diabetes and Metabolism, Burns and Allen Research Institute, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, California 90048, USA
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31
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Abstract
The vitamin D endocrine system plays an essential role in calcium homeostasis and bone metabolism, but research during the past two decades has revealed a diverse range of biological actions that include induction of cell differentiation, inhibition of cell growth, immunomodulation, and control of other hormonal systems. Vitamin D itself is a prohormone that is metabolically converted to the active metabolite, 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. This vitamin D hormone activates its cellular receptor (vitamin D receptor or VDR), which alters the transcription rates of target genes responsible for the biological responses. This review focuses on several recent developments that extend our understanding of the complexities of vitamin D metabolism and actions: the final step in the activation of vitamin D, conversion of 25-hydroxyvitamin D to 1,25(OH)(2)D in renal proximal tubules, is now known to involve facilitated uptake and intracellular delivery of the precursor to 1alpha-hydroxylase. Emerging evidence using mice lacking the VDR and/or 1alpha-hydroxylase indicates both 1,25(OH)(2)D(3)-dependent and -independent actions of the VDR as well as VDR-dependent and -independent actions of 1,25(OH)(2)D(3). Thus the vitamin D system may involve more than a single receptor and ligand. The presence of 1alpha-hydroxylase in many target cells indicates autocrine/paracrine functions for 1,25(OH)(2)D(3) in the control of cell proliferation and differentiation. This local production of 1,25(OH)(2)D(3) is dependent on circulating precursor levels, providing a potential explanation for the association of vitamin D deficiency with various cancers and autoimmune diseases.
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Affiliation(s)
- Adriana S Dusso
- Renal Division, Washington University School of Medicine, St. Louis, MO 63110-1093, USA
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32
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Chen H, Hewison M, Hu B, Sharma M, Sun Z, Adams JS. An Hsp27-related, dominant-negative-acting intracellular estradiol-binding protein. J Biol Chem 2004; 279:29944-51. [PMID: 15123601 DOI: 10.1074/jbc.m401317200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
New World primates (NWPs) exhibit a compensated form of resistance to gonadal steroid hormones. We demonstrated recently that estrogen resistance in NWP cells was associated with the overexpression of two proteins, a nonreceptor-related, dominant-negative-acting estrogen response element (ERE)-binding protein (ERE-BP) and an intracellular estradiol-binding protein (IEBP). Based on the N-terminal sequences of tryptic fragments of IEBP isolated from a 17beta-estradiol (E2) affinity column we cloned a full-length cDNA for IEBP from the estrogen-resistant NWP cell line, B95-8. Subsequent sequence analysis revealed 87% sequence identity between the deduced peptide for IEBP and human Hsp27. When hormone-responsive, wild-type Old World primate (OWP) cells were transiently transfected with IEBP cDNA, E2-directed ERE reporter luciferase activity was reduced by 50% compared with vector only-transfected OWP cells (p < 0.0018). When IEBP and ERE-BP were cotransfected, ERE promoter-reporter activity was reduced by a further 60% (p < 0.0001). Electrophoresis mobility shift analyses showed that IEBP neither bound to ERE nor competed with the estrogen receptor (ER) for binding to ERE. However, there was evidence of protein-protein interaction of IEBP and ERalpha; IEBP was coimmunoprecipitated with anti-ERalpha antibody in wild-type cells stably transfected with IEBP. A specific interaction between ERalpha and IEBP was confirmed in glutathione S-transferase pull-down and yeast two-hybrid assays. Data indicate that the Hsp27-related IEBP interacts with the ligand binding domain of the ERalpha. In summary, by inhibiting the ERalpha-E2 interaction, IEBP acts to squelch ERalpha-directed ERE-regulated transactivation and promote estrogen resistance in NWP cells.
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MESH Headings
- Amino Acid Sequence
- Animals
- Blotting, Western
- Callithrix
- Carrier Proteins/chemistry
- Carrier Proteins/metabolism
- Cell Line
- Cell Nucleus/metabolism
- Cloning, Molecular
- DNA, Complementary/metabolism
- Dose-Response Relationship, Drug
- Estradiol/metabolism
- Estrogen Receptor alpha
- Genes, Dominant
- Genes, Reporter
- Glutathione Transferase/metabolism
- Intracellular Signaling Peptides and Proteins
- Ligands
- Macaca mulatta
- Models, Biological
- Molecular Sequence Data
- Peptides/chemistry
- Precipitin Tests
- Promoter Regions, Genetic
- Protein Binding
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Receptors, Estrogen/metabolism
- Transcription, Genetic
- Transcriptional Activation
- Transfection
- Two-Hybrid System Techniques
- alpha-Crystallins/chemistry
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Affiliation(s)
- Hong Chen
- Division of Endocrinology, Diabetes, and Metabolism, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, California 90048, USA
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