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Warren MF, Vu TC, Toomer OT, Fernandez JD, Livingston KA. Efficacy of 1-α-Hydroxycholecalciferol Supplementation in Young Broiler Feed Suggests Reducing Calcium Levels at Grower Phase. Front Vet Sci 2020; 7:245. [PMID: 32587863 PMCID: PMC7299047 DOI: 10.3389/fvets.2020.00245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/14/2020] [Indexed: 11/18/2022] Open
Abstract
Increasing biopotency of cholecalciferol (D3) from vitamin sources is essential in the poultry industry to meet nutritional demands and counter stressors. D3 exhibits hormonal traits and is responsible for calcium (Ca) absorption. 1-α-Hydroxycholecalciferol (1α) is a synthetic form of D3 that has equal efficacy and is cheaper to synthesize than 1,25-dihydroxycholecalciferol (active form of D3), on broilers. However, 1α bypasses a critical regulatory point, the kidney, and may consequently lead to toxicity levels of Ca via Ca absorption. This study examined 1α supplementation in broiler diets with different Ca inclusion levels to determine if 1α at higher Ca levels caused Ca toxicity at starter and grower phases with Ross 708 male broiler chicks. In Experiment 1 (1–15 days of age), chicks were assigned to one of 10 treatment starter diets with five levels of Ca inclusion (0.80, 0.95, 1.10, 1.25, and 1.40%) with or without 1α supplementation (5 μg 1α/kg in feed) and eight replicate cages per treatment. In Experiment 2, chicks were fed common starter diet until 16 days of age, and then they were assigned to one of eight treatment diets with four levels of Ca inclusion (0.54, 0.76, 0.98, or 1.20%) with or without 1α supplementation (5 μg 1α/kg in feed). At the end of both experiments, blood was collected from broilers to determine blood chemistry, including concentrations of vitamin D metabolites. Intestinal tissues were also collected to examine gene expression. In Experiment 1, broilers not fed 1α exhibited a quadratic effect in ionized blood Ca (iCa) as dietary Ca inclusion levels increased; 1α-fed broilers displayed an increase in iCa as Ca inclusion levels increased (p = 0.0002). For Experiment 2, 1α-fed broilers displayed a decrease in 25-hydroxycholecalciferol plasma concentration as dietary Ca inclusion levels increased (p = 0.035); also, increasing Ca inclusion in diets increased expression of duodenal sodium phosphate cotransporter type II b (NPTIIb, p = 0.03). Our findings imply that inclusion of 1α was beneficial because 1α enhanced Ca absorption during the starter phase; however, to avoid potential Ca toxicity or antagonism while using 1α during the grower phase, there should be consideration with reducing dietary Ca levels.
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Affiliation(s)
- Matthew F Warren
- Prestage Department of Poultry Science, North Carolina State University, Raleigh, NC, United States
| | - Thien C Vu
- United States Department of Agriculture, Agricultural Research Service, Raleigh, NC, United States
| | - Ondulla T Toomer
- United States Department of Agriculture, Agricultural Research Service, Raleigh, NC, United States
| | | | - Kimberly A Livingston
- Prestage Department of Poultry Science, North Carolina State University, Raleigh, NC, United States.,Elanco Animal Health, Greenfield, IN, United States
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52
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Fleet JC, Reyes-Fernandez P. Intestinal responses to 1,25 dihydroxyvitamin D are not improved by higher intestinal VDR levels resulting from intestine-specific transgenic expression of VDR in mice. J Steroid Biochem Mol Biol 2020; 200:105670. [PMID: 32283207 DOI: 10.1016/j.jsbmb.2020.105670] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 01/28/2020] [Accepted: 04/02/2020] [Indexed: 12/21/2022]
Abstract
Intestinal calcium (Ca) absorption depends upon vitamin D signaling through the vitamin D receptor (VDR) in the proximal and distal intestine while lower VDR content causes intestinal resistance to 1,25 dihydroxyvitamin D (1,25(OH)2 D) action. We tested whether intestinal responsiveness to 1,25(OH)2 D is increased in mice with higher than normal VDR levels resulting from transgenic VDR expression in the whole intestine (villin promoter-human VDR transgene, HV2). Wild type (WT) and HV2 mice were treated with 0, 0.15, or 0.3 ng 1,25(OH)2 D/g body weight (BW) (n = 6/dose) for 6 h. 1,25(OH)2 D significantly induced Cyp24a1, Trpv6, and S100 g mRNA in duodenum (Dd) of WT mice but induction was not higher in HV2 mice. We next tested whether higher intestinal VDR could protect mice from the consequences of low dietary Ca intake. WT and HV2 mice were fed diets with 0.125, 0.25, 0.5 (reference), or 1% Ca from weaning to 3 months of age (n = 9/diet/genotype). Dietary Ca restriction caused a dose dependent increase in serum 1,25(OH)2 D, Dd TRPV6, and Dd S100 g mRNA in WT mice and the effect was greater in HV2 mice. While Ca absorption was increased by low Ca intake, there was no difference in Ca absorption between HV2 and WT mice. Similarly, while bone density and microstructure were reduced by low Ca intake in WT mice, high intestinal VDR in HV2 mice did not protect bone in mice fed low Ca diets. Thus, while intestinal VDR and vitamin D signaling are essential for normal Ca metabolism during growth, our data demonstrate that higher than normal intestinal VDR levels do not improve the intestinal response to either 1,25(OH)2 D injection or to elevated 1,25(OH)2 D levels resulting from the physiologic adaptation to low Ca diets.
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Affiliation(s)
- James C Fleet
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47906-2059, United States.
| | - Perla Reyes-Fernandez
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47906-2059, United States
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53
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Zhang YG, Lu R, Wu S, Chatterjee I, Zhou D, Xia Y, Sun J. Vitamin D Receptor Protects Against Dysbiosis and Tumorigenesis via the JAK/STAT Pathway in Intestine. Cell Mol Gastroenterol Hepatol 2020; 10:729-746. [PMID: 32497792 PMCID: PMC7498955 DOI: 10.1016/j.jcmgh.2020.05.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Vitamin D exerts regulatory roles via vitamin D receptor (VDR) in mucosal immunity, host defense, and inflammation involving host factors and microbiome. Human Vdr gene variation shapes the microbiome and VDR deletion leads to dysbiosis. Low VDR expression and diminished vitamin D/VDR signaling are observed in colon cancer. Nevertheless, how intestinal epithelial VDR is involved in tumorigenesis through gut microbiota remains unknown. We hypothesized that intestinal VDR protects mice against dysbiosis via modulating the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway in tumorigenesis. METHODS To test our hypothesis, we used an azoxymethane/dextran sulfate sodium-induced cancer model in intestinal VDR conditional knockout (VDRΔIEC) mice, cell cultures, stem cell-derived colonoids, and human colon cancer samples. RESULTS VDRΔIEC mice have higher numbers of tumors, with the location shifted from the distal to proximal colon. Fecal microbiota analysis showed that VDR deletion leads to a bacterial profile shift from normal to susceptible carcinogenesis. We found enhanced bacterial staining in mouse and human tumors. Microbial metabolites from VDRΔIEC mice showed increased secondary bile acids, consistent with observations in human CRC. We further identified that VDR protein bound to the Jak2 promoter, suggesting that VDR transcriptionally regulated Jak2. The JAK/STAT pathway is critical in intestinal and microbial homeostasis. Fecal samples from VDRΔIEC mice activate the STAT3 signaling in human and mouse organoids. Lack of VDR led to hyperfunction of Jak2 in response to intestinal dysbiosis. A JAK/STAT inhibitor abolished the microbiome-induced activation of STAT3. CONCLUSIONS We provide insights into the mechanism of VDR dysfunction leading to dysbiosis and tumorigenesis. It indicates a new target: microbiome and VDR for the prevention of cancer.
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Affiliation(s)
- Yong-Guo Zhang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Rong Lu
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shaoping Wu
- Department of Biochemistry, Rush University, Chicago, Illinois
| | - Ishita Chatterjee
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - David Zhou
- Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, Missouri
| | - Yinglin Xia
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Jun Sun
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois,University of Illinois at Chicago Cancer Center, University of Illinois at Chicago, Chicago, Illinois,Correspondence Address correspondence to: Jun Sun, PhD, AGAF, FAPS, Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, 840 S Wood Street, Room 704 CSB, MC716 Chicago, Illinois 60612. fax: (312) 996-6010.
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54
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Chinda D, Shimoyama T, Sawada K, Iino C, Sakuraba H, Nakaji S, Fukuda S. Lifestyle Factors Rather Than Helicobacter pylori Infection or Estradiol Level are Associated With Osteopenia in Japanese Men. Am J Mens Health 2020; 13:1557988319848219. [PMID: 31043139 PMCID: PMC6498780 DOI: 10.1177/1557988319848219] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Although decreased calcium absorption, decreased bone formation, alcohol
drinking, and smoking have been considered as causes of osteopenia in men, the
cause is unknown in half of the cases. Many reports highlighted the association
between Helicobacter pylori infection and
osteoporosis, mainly in East Asia and Japan. To identify relevant factors of
osteoporosis in men, we examined estrogen and calcium intakes and other
lifestyle factors together with gastric mucosal atrophy caused by Helicobacter pylori infection. This study is a
cross-sectional study design of 268 healthy men who underwent general medical
examinations. Multivariate analysis was performed, with age, body mass index,
smoking habit, drinking habit, exercise habit, estradiol level, calcium intake,
and Helicobacter pylori infection and its
associated gastric mucosal atrophy as the independent variables and the presence
of osteopenia as the dependent variable. The adjusted odds ratio was 0.74 (95%
Confidence Interval [0.29, 1.90], p = .531) and
1.31 (95% Confidence Interval [0.54, 3.21], p =
.552), when Helicobacter pylori infection was
positive without and with gastric mucosal atrophy, respectively. Helicobacter pylori infection and gastric mucosal
atrophy were not significant factors. Low body mass index, smoking habit, and
low calcium intake were significantly associated with decreased bone density. In
conclusion, Helicobacter pylori infection was not
a significant risk, whereas low body mass index, current smoking, and lower
calcium intake had a significant influence on the development of osteopenia in
men.
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Affiliation(s)
- Daisuke Chinda
- 1 Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Japan.,2 Department of Community Medicine, Hirosaki University Graduate School of Medicine, Japan
| | - Tadashi Shimoyama
- 1 Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Japan.,3 Aomori General Health Examination Center, Japan
| | - Kaori Sawada
- 4 Department of Social Medicine, Hirosaki University Graduate School of Medicine, Japan
| | - Chikara Iino
- 1 Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Japan
| | - Hirotake Sakuraba
- 1 Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Japan
| | - Shigeyuki Nakaji
- 4 Department of Social Medicine, Hirosaki University Graduate School of Medicine, Japan
| | - Shinsaku Fukuda
- 1 Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Japan
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55
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Li W, Zimmerman SE, Peregrina K, Houston M, Mayoral J, Zhang J, Maqbool S, Zhang Z, Cai Y, Ye K, Augenlicht LH. The nutritional environment determines which and how intestinal stem cells contribute to homeostasis and tumorigenesis. Carcinogenesis 2020; 40:937-946. [PMID: 31169292 DOI: 10.1093/carcin/bgz106] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 05/28/2019] [Accepted: 06/04/2019] [Indexed: 02/07/2023] Open
Abstract
Sporadic colon cancer accounts for approximately 80% of colorectal cancer (CRC) with high incidence in Western societies strongly linked to long-term dietary patterns. A unique mouse model for sporadic CRC results from feeding a purified rodent Western-style diet (NWD1) recapitulating intake for the mouse of common nutrient risk factors each at its level consumed in higher risk Western populations. This causes sporadic large and small intestinal tumors in wild-type mice at an incidence and frequency similar to that in humans. NWD1 perturbs intestinal cell maturation and Wnt signaling throughout villi and colonic crypts and decreases mouse Lgr5hi intestinal stem cell contribution to homeostasis and tumor development. Here we establish that NWD1 transcriptionally reprograms Lgr5hi cells, and that nutrients are interactive in reprogramming. Furthermore, the DNA mismatch repair pathway is elevated in Lgr5hi cells by lower vitamin D3 and/or calcium in NWD1, paralleled by reduced accumulation of relevant somatic mutations detected by single-cell exome sequencing. In compensation, NWD1 also reprograms Bmi1+ cells to function and persist as stem-like cells in mucosal homeostasis and tumor development. The data establish the key role of the nutrient environment in defining the contribution of two different stem cell populations to both mucosal homeostasis and tumorigenesis. This raises important questions regarding impact of variable human diets on which and how stem cell populations function in the human mucosa and give rise to tumors. Moreover, major differences reported in turnover of human and mouse crypt base stem cells may be linked to their very different nutrient exposures.
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Affiliation(s)
- Wenge Li
- Department of Medicine, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Samuel E Zimmerman
- Systems and Computational Biology, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Karina Peregrina
- Department of Medicine, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Michele Houston
- Department of Medicine, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Joshua Mayoral
- Pathology, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Jinghang Zhang
- Microbiology and Immunology, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Shahina Maqbool
- Genetics, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Zhengdong Zhang
- Genetics, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Ying Cai
- Genetics, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Kenny Ye
- Epidemiology and Population Health, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
| | - Leonard H Augenlicht
- Department of Medicine, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA.,Cell Biology, Albert Einstein College of Medicine, Ullmann, Bronx, NY, USA
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56
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Jiang H, Horst RL, Koszewski NJ, Goff JP, Christakos S, Fleet JC. Targeting 1,25(OH) 2D-mediated calcium absorption machinery in proximal colon with calcitriol glycosides and glucuronides. J Steroid Biochem Mol Biol 2020; 198:105574. [PMID: 31881310 DOI: 10.1016/j.jsbmb.2019.105574] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 12/14/2022]
Abstract
High intestinal calcium (Ca) absorption efficiency is associated with high peak bone mass in adolescents and reduced bone loss in adulthood. Transepithelial intestinal Ca absorption is mediated by 1,25-dihydroxyvitamin D (1,25(OH)2D, calcitriol) through the vitamin D receptor (VDR). Most research on Ca absorption focuses on the proximal small intestine but evidence shows that large intestine plays a crucial role in whole body Ca homeostasis. We directly assessed and compared Ca absorption capacity at the proximal colon and duodenum using in situ ligated loops (2 mM Ca, 10 min). In C57BL/6 J mice, the proximal colon (26.2 ± 3.7 %) had comparable ability to absorb Ca as the duodenum (30.0 ± 6.7 %). In VDR knockout (KO) mice, Ca absorption efficiency was reduced by 67 % in duodenum and 48 % in proximal colon. These data suggest that large intestine could be targeted to improve Ca absorption and protect bone in at risk-groups (e.g. bariatric patients). Glycoside forms of calcitriol found in Solanum Glaucophyllum (Sg) leaf are biologically inert but can be activated in the colon upon bacterial cleavage of the glycosides. We conducted a study to test whether Sg leaf, as well as a novel, synthetic 1,3-diglucuronide form of calcitriol (1,3-diG) could target the proximal colon and upregulate genes involved in Ca absorption (i.e. Trpv6, S100g). 13-week-old female C57BL6/J mice were fed AIN93 G diet containing increasing levels of one of the two compounds for 2 weeks (delivering 0, 0.25, 0.5, 1, or 2 ng calcitriol equivalent per day). Both compounds induced a dose-dependent upregulation of Cyp24a1 and Trpv6 gene expression in the proximal colon. 1,3-diG also induced S100g gene expression in the proximal colon. Duodenal expression of Trpv6 was upregulated at higher doses of 1,3-diG but not Sg leaf. These data suggest that both glycosylated and glucuronidated calcitriol could be used to target the proximal colon but that dosing must be optimized to limit systemic effects that could cause hypercalcemia. Future studies will test the translational potential of these compounds to determine if they can increase Ca absorption at proximal colon and whether this can help protect bone.
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Affiliation(s)
- H Jiang
- Dept. of Nutrition Science, Purdue University, IN, United States
| | - R L Horst
- Heartland Assays, Inc., Ames, IA, United States; GlycoMyr Inc., Ames, IA, United States
| | - N J Koszewski
- GlycoMyr Inc., Ames, IA, United States; Dept. Biomedical Sciences, College of Veterinary Medicine, Iowa State U., IA, United States
| | - J P Goff
- GlycoMyr Inc., Ames, IA, United States; Dept. Biomedical Sciences, College of Veterinary Medicine, Iowa State U., IA, United States
| | - S Christakos
- Dept. of Microbiology, Biochemistry and Molecular Genetics, Rutgers, New Jersey Medical School, NJ, United States
| | - J C Fleet
- Dept. of Nutrition Science, Purdue University, IN, United States.
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57
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Probiotic Lactobacillus strains from Mongolia improve calcium transport and uptake by intestinal cells in vitro. Food Res Int 2020; 133:109201. [PMID: 32466902 DOI: 10.1016/j.foodres.2020.109201] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 03/23/2020] [Accepted: 03/26/2020] [Indexed: 01/04/2023]
Abstract
The aim of this study was to investigate the probiotic properties of 174 Lactobacillus strains isolated from Mongolian dairy products, and particularly their impact on intestinal calcium uptake and absorption. All isolates underwent a first screening based on cell surface hydrophobicity, acid tolerance, tolerance to gastro-intestinal digestion, autoaggregation, adhesion and cytotoxicity against intestinal cells. Six Lactobacillus strains from different species (L. casei, L. kefiranofaciens, L. plantarum, L. fermentum, L. helveticus and L. delbrueckii) were selected, and their impact on intestinal calcium uptake and transport was investigated using Caco-2. Five strains were able to improve total calcium transport after 24 h contact with a differentiated Caco-2 cell monolayer. Concomitantly the L. plantarum strain was able to increase cellular calcium uptake in Caco-2 cells by 10% in comparison to control conditions. To determine which pathway(s) of calcium absorption was modulated by the strains, a qPCR-based study on 4 genes related to calcium/vitamin D metabolism or tight junction integrity was conducted on mucus-secreting intestinal HT-29 MTX cells. The L. plantarum strain modulates the transcellular pathway by regulating the expression of vitamin D receptor (1.79 fold of control) and calcium transporter (4.77 fold of control) while the L. delbrueckii strain acts on the paracellular pathway by modulating claudin-2 expression (2.83 fold of control). This work highlights the impact of Lactobacillus probiotic strains on intestinal calcium absorption and for the first time give some evidence about the cellular pathways involved.
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58
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Zhang YG, Xia Y, Sun J. A simple and sensitive method to detect vitamin D receptor expression in various disease models using stool samples. Genes Dis 2020; 8:939-945. [PMID: 34522720 PMCID: PMC8427243 DOI: 10.1016/j.gendis.2020.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/24/2020] [Accepted: 03/06/2020] [Indexed: 01/16/2023] Open
Abstract
Vitamin D receptor (VDR) executes the main biological functions of its ligand vitamin D. VDR/vitamin D plays critical roles in regulating host immunity, maintaining barrier functions, and shaping gut microbiome. Reduction of intestinal VDR has been reported in various diseases, including inflammatory diseases and colon cancer. However, it is always challenging to get biopsies to test the pathologic changes of VDR in intestine. In the current study, we reported a simple and sensitive quantitative PCR (qPCR) method to detect reduction of intestinal VDR using fecal samples. We validated this method in several experimental models, such as colitis, bacterial infection, and aging. We further correlated the qPCR data of VDR with the protein level of VDR in colon or serum 25 (OH)D3 in mice with different VDR status (VDR+/+, VDR+/-, and VDR−/−). Our data indicate that the qPCR method to test VDR using fecal samples could detect the expression level of intestinal VDR in various diseases. Our study highlights the feasibility, sensitivity, and simplicity of a molecular method to study the status of VDR as a biomarker.
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Affiliation(s)
- Yong-Guo Zhang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Yinglin Xia
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Jun Sun
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.,UIC Cancer Center, University of Illinois at Chicago, Chicago, IL 60612, USA.,Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60612, USA
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59
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Hanazaki A, Ikuta K, Sasaki S, Sasaki S, Koike M, Tanifuji K, Arima Y, Kaneko I, Shiozaki Y, Tatsumi S, Hasegawa T, Amizuka N, Miyamoto K, Segawa H. Role of sodium-dependent Pi transporter/Npt2c on Pi homeostasis in klotho knockout mice different properties between juvenile and adult stages. Physiol Rep 2020; 8:e14324. [PMID: 32026654 PMCID: PMC7002534 DOI: 10.14814/phy2.14324] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
SLC34A3/NPT2c/NaPi-2c/Npt2c is a growth-related NaPi cotransporter that mediates the uptake of renal sodium-dependent phosphate (Pi). Mutation of human NPT2c causes hereditary hypophosphatemic rickets with hypercalciuria. Mice with Npt2c knockout, however, exhibit normal Pi metabolism. To investigate the role of Npt2c in Pi homeostasis, we generated α-klotho-/- /Npt2c-/- (KL2cDKO) mice and analyzed Pi homeostasis. α-Klotho-/- (KLKO) mice exhibit hyperphosphatemia and markedly increased kidney Npt2c protein levels. Genetic disruption of Npt2c extended the lifespan of KLKO mice similar to that of α-Klotho-/- /Npt2a-/- mice. Adult KL2cDKO mice had hyperphosphatemia, but analysis of Pi metabolism revealed significantly decreased intestinal and renal Pi (re)absorption compared with KLKO mice. The 1,25-dihydroxy vitamin D3 concentration was not reduced in KL2cDKO mice compared with that in KLKO mice. The KL2cDKO mice had less severe soft tissue and vascular calcification compared with KLKO mice. Juvenile KL2cDKO mice had significantly reduced plasma Pi levels, but Pi metabolism was not changed. In Npt2cKO mice, plasma Pi levels began to decrease around the age of 15 days and significant hypophosphatemia developed within 21 days. The findings of the present study suggest that Npt2c contributes to regulating plasma Pi levels in the juvenile stage and affects Pi retention in the soft and vascular tissues in KLKO mice.
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Affiliation(s)
- Ai Hanazaki
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Kayo Ikuta
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Shohei Sasaki
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Sumire Sasaki
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Megumi Koike
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Kazuya Tanifuji
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Yuki Arima
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Ichiro Kaneko
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Yuji Shiozaki
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Sawako Tatsumi
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Tomoka Hasegawa
- Developmental Biology of Hard TissueHokkaido University Graduate School of Dental MedicineSapporoJapan
| | - Norio Amizuka
- Developmental Biology of Hard TissueHokkaido University Graduate School of Dental MedicineSapporoJapan
| | - Ken‐ichi Miyamoto
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
| | - Hiroko Segawa
- Department of Applied NutritionInstitute of Biomedical SciencesTokushima University Graduate School TokushimaTokushimaJapan
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60
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Christakos S, Li S, De La Cruz J, Shroyer NF, Criss ZK, Verzi MP, Fleet JC. Vitamin D and the intestine: Review and update. J Steroid Biochem Mol Biol 2020; 196:105501. [PMID: 31655181 PMCID: PMC6954280 DOI: 10.1016/j.jsbmb.2019.105501] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 10/04/2019] [Accepted: 10/14/2019] [Indexed: 12/11/2022]
Abstract
The central role of vitamin D in calcium homeostasis is to increase calcium absorption from the intestine. This article describes the early work that served as the foundation for the initial model of vitamin D mediated calcium absorption. In addition, other research related to the role of vitamin D in the intestine, including those which have challenged the traditional model and the crucial role of specific calcium transport proteins, are reviewed. More recent work identifying novel targets of 1,25(OH)2D3 action in the intestine and highlighting the importance of 1,25(OH)2D3 action across the proximal/distal and crypt/villus axes in the intestine is summarized.
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Affiliation(s)
- Sylvia Christakos
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA.
| | - Shanshan Li
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA
| | - Jessica De La Cruz
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers, The State University of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA
| | - Noah F Shroyer
- Integrative Molecular and Biomedical Sciences Graduate Program, Division of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zachary K Criss
- Integrative Molecular and Biomedical Sciences Graduate Program, Division of Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Michael P Verzi
- Department of Genetics, Rutgers University, New Brunswick, NJ 08854, USA
| | - James C Fleet
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
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61
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Lee PW, Selhorst A, Lampe SG, Liu Y, Yang Y, Lovett-Racke AE. Neuron-Specific Vitamin D Signaling Attenuates Microglia Activation and CNS Autoimmunity. Front Neurol 2020; 11:19. [PMID: 32082243 PMCID: PMC7005247 DOI: 10.3389/fneur.2020.00019] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/08/2020] [Indexed: 01/08/2023] Open
Abstract
Low vitamin D during childhood is associated with an increased risk of developing multiple sclerosis (MS) as an adult. Given that vitamin D has anti-inflammatory properties, it has been postulated that the relationship between MS and low vitamin D is due to immune dysregulation. Since the vitamin D receptor (VDR) is expressed in many cell types, this study investigated an alternative hypothesis-neuron-specific VDR signaling induces anti-inflammatory molecules that protect the central nervous system from autoimmunity. Using media from neurons treated with calcitriol, the active form of vitamin D3, LPS-activated microglia had a reduction in pro-inflammatory molecules, and a reciprocal induction of anti-inflammatory molecules. Since IL-34 is critical to the homeostasis of microglia, and was previously shown to be induced in endothelial cells by vitamin D, we investigated IL-34 as the potential anti-inflammatory molecule induced in neurons by vitamin D. Treatment of LPS-activated microglia with IL-34 reduced pro-inflammatory cytokine production and enhanced the expression of anti-inflammatory transcripts. However, neutralizing IL-34 in vitamin D neuronal conditioned media only impacted IL-6 and not the broader anti-inflammatory phenotype of microglia. To mimic low vitamin D in children, we used a neuron-specific inducible mouse model in which VDR was partially deleted in juvenile mice. Partial deletion of VDR in neurons during early life resulted in exacerbated CNS autoimmunity in adult mice. Overall, the study illustrated that vitamin D signaling in neurons promotes an anti-inflammatory state in microglia, and low vitamin D in early life may enhance CNS autoimmunity.
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Affiliation(s)
- Priscilla W. Lee
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Amanda Selhorst
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Sara Gombash Lampe
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Yue Liu
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Yuhong Yang
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Amy E. Lovett-Racke
- Department of Microbial Infection and Immunity, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Neuroscience, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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62
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Paubelle E, Zylbersztejn F, Maciel TT, Carvalho C, Mupo A, Cheok M, Lieben L, Sujobert P, Decroocq J, Yokoyama A, Asnafi V, Macintyre E, Tamburini J, Bardet V, Castaigne S, Preudhomme C, Dombret H, Carmeliet G, Bouscary D, Ginzburg YZ, de Thé H, Benhamou M, Monteiro RC, Vassiliou GS, Hermine O, Moura IC. Vitamin D Receptor Controls Cell Stemness in Acute Myeloid Leukemia and in Normal Bone Marrow. Cell Rep 2020; 30:739-754.e4. [PMID: 31968250 DOI: 10.1016/j.celrep.2019.12.055] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 02/24/2019] [Accepted: 12/16/2019] [Indexed: 02/06/2023] Open
Abstract
Vitamin D (VD) is a known differentiating agent, but the role of VD receptor (VDR) is still incompletely described in acute myeloid leukemia (AML), whose treatment is based mostly on antimitotic chemotherapy. Here, we present an unexpected role of VDR in normal hematopoiesis and in leukemogenesis. Limited VDR expression is associated with impaired myeloid progenitor differentiation and is a new prognostic factor in AML. In mice, the lack of Vdr results in increased numbers of hematopoietic and leukemia stem cells and quiescent hematopoietic stem cells. In addition, malignant transformation of Vdr-/- cells results in myeloid differentiation block and increases self-renewal. Vdr promoter is methylated in AML as in CD34+ cells, and demethylating agents induce VDR expression. Association of VDR agonists with hypomethylating agents promotes leukemia stem cell exhaustion and decreases tumor burden in AML mouse models. Thus, Vdr functions as a regulator of stem cell homeostasis and leukemic propagation.
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Affiliation(s)
- Etienne Paubelle
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Department of Clinical Hematology, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, 75015 Paris, France.
| | - Florence Zylbersztejn
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France
| | - Thiago Trovati Maciel
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France
| | - Caroline Carvalho
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France
| | - Annalisa Mupo
- Haematological Cancer Genetics, Wellcome Trust Genome Campus, Wellcome Trust Sanger Institute, Hinxton Cambridge CB10 1SA, UK
| | - Meyling Cheok
- Centre of Research Jean-Pierre Aubert, INSERM UMR 837, 59000 Lille, France
| | - Liesbet Lieben
- Laboratory of Experimental Medicine and Endocrinology, KU Leuven 3000, Belgium
| | - Pierre Sujobert
- Institut Cochin, Département d'Immuno-Hématologie, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, INSERM U1016 Paris, France; Université Paris Descartes, Faculté de Médecine Sorbonne Paris Cité, Paris, France; Equipe Labellisée Ligue Nationale Contre le Cancer (LNCC), Paris, France
| | - Justine Decroocq
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France
| | - Akihiko Yokoyama
- National Cancer Center Research Institute, Chiba 277-8577, Japan
| | - Vahid Asnafi
- Department of Biological Hematology, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, 75015 Paris, France
| | - Elizabeth Macintyre
- Department of Biological Hematology, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, 75015 Paris, France
| | - Jérôme Tamburini
- Institut Cochin, Département d'Immuno-Hématologie, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, INSERM U1016 Paris, France; Université Paris Descartes, Faculté de Médecine Sorbonne Paris Cité, Paris, France; Equipe Labellisée Ligue Nationale Contre le Cancer (LNCC), Paris, France
| | - Valérie Bardet
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France
| | - Sylvie Castaigne
- Department of Hematology, Hôpital Mignot, 78150 Le Chesnay, France
| | - Claude Preudhomme
- Centre of Research Jean-Pierre Aubert, INSERM UMR 837, 59000 Lille, France
| | - Hervé Dombret
- Department of Hematology, Assistance Publique-Hôpitaux de Paris, Hôpital Saint-Louis, 75010 Paris, France
| | - Geert Carmeliet
- Laboratory of Experimental Medicine and Endocrinology, KU Leuven 3000, Belgium
| | - Didier Bouscary
- Institut Cochin, Département d'Immuno-Hématologie, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, INSERM U1016 Paris, France; Université Paris Descartes, Faculté de Médecine Sorbonne Paris Cité, Paris, France; Equipe Labellisée Ligue Nationale Contre le Cancer (LNCC), Paris, France
| | - Yelena Z Ginzburg
- Erythropoiesis Laboratory, LFKRI, New York Blood Center, New York, NY, USA
| | - Hughes de Thé
- Molecular Virology and Pathology, INSERM UMR 944, 75010 Paris, France; Molecular Virology and Pathology, CNRS 7212, 75010 Paris, France
| | - Marc Benhamou
- INSERM U1149, Center for Research on Inflammation, 75018 Paris, France
| | - Renato C Monteiro
- INSERM U1149, Center for Research on Inflammation, 75018 Paris, France
| | - George S Vassiliou
- Haematological Cancer Genetics, Wellcome Trust Genome Campus, Wellcome Trust Sanger Institute, Hinxton Cambridge CB10 1SA, UK
| | - Olivier Hermine
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Department of Clinical Hematology, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, 75015 Paris, France; Laboratory of Excellence GR-Ex, 75015 Paris, France.
| | - Ivan C Moura
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Paris Descartes - Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France; CNRS ERL 8254, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, 75015 Paris, France; Laboratory of Excellence GR-Ex, 75015 Paris, France
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63
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Girgis CM, Cha KM, So B, Tsang M, Chen J, Houweling PJ, Schindeler A, Stokes R, Swarbrick MM, Evesson FJ, Cooper ST, Gunton JE. Mice with myocyte deletion of vitamin D receptor have sarcopenia and impaired muscle function. J Cachexia Sarcopenia Muscle 2019; 10:1228-1240. [PMID: 31225722 PMCID: PMC6903451 DOI: 10.1002/jcsm.12460] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND It has long been recognized that vitamin D deficiency is associated with muscle weakness and falls. Vitamin D receptor (VDR) is present at very low levels in normal muscle. Whether vitamin D plays a direct role in muscle function is unknown and is a subject of hot debate. Myocyte-specific deletion of VDR would provide a strategy to answer this question. METHODS Myocyte-specific vitamin D receptor (mVDR) null mice were generated by crossing human skeletal actin-Cre mice with floxed VDR mice. The effects of gene deletion on the muscle phenotype were studied in terms of body tissue composition, muscle tissue histology, and gene expression by real-time PCR. RESULTS Unlike whole-body VDR knockout mice, mVDR mice showed a normal body size. The mVDR showed a distinct muscle phenotype featuring reduced proportional lean mass (70% vs. 78% of lean mass), reduced voluntary wheel-running distance (22% decrease, P = 0.009), reduced average running speed, and reduced grip strength (7-16% reduction depending on age at testing). With their decreased voluntary exercise, and decreased lean mass, mVDR have increased proportional fat mass at 20% compared with 13%. Surprisingly, their muscle fibres showed slightly increased diameter, as well as the presence of angular fibres and central nuclei suggesting ongoing remodelling. There were, however, no clear changes in fibre type and there was no increase in muscle fibrosis. VDR is a transcriptional regulator, and changes in the expression of candidate genes was examined in RNA extracted from skeletal muscle. Alterations were seen in myogenic gene expression, and there was decreased expression of cell cycle genes cyclin D1, D2, and D3 and cyclin-dependent kinases Cdk-2 and Cdk-4. Expression of calcium handling genes sarcoplasmic/endoplasmic reticulum calcium ATPases (SERCA) Serca2b and Serca3 was decreased and Calbindin mRNA was lower in mVDR muscle. CONCLUSIONS This study demonstrates that vitamin D signalling is needed for myocyte function. Despite the low level of VDR protein normally found muscle, deleting myocyte VDR had important effects on muscle size and strength. Maintenance of normal vitamin D signalling is a useful strategy to prevent loss of muscle function and size.
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Affiliation(s)
- Christian M Girgis
- Department of Diabetes and Endocrinology, Westmead Hospital, Sydney, New South Wales, Australia.,Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia.,Department of Diabetes and Endocrinology, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Kuan Minn Cha
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Benjamin So
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Michael Tsang
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Jennifer Chen
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Peter J Houweling
- Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Aaron Schindeler
- Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Westmead, Australia
| | - Rebecca Stokes
- The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Michael M Swarbrick
- Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Frances J Evesson
- Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,Kids Neuroscience Centre, The Children's Hospital at Westmead, The Discipline of Child and Adolescent Health, Children's Medical Research Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Sandra T Cooper
- Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,Kids Neuroscience Centre, The Children's Hospital at Westmead, The Discipline of Child and Adolescent Health, Children's Medical Research Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Jenny E Gunton
- Department of Diabetes and Endocrinology, Westmead Hospital, Sydney, New South Wales, Australia.,Faculty of Health and Medicine, The University of Sydney, Sydney, New South Wales, Australia.,The Westmead Institute for Medical Research, The University of Sydney, Sydney, New South Wales, Australia.,Division of Immunology, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
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64
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Hassanshahi M, Anderson PH, Sylvester CL, Stringer AM. Current evidence for vitamin D in intestinal function and disease. Exp Biol Med (Maywood) 2019; 244:1040-1052. [PMID: 31366237 DOI: 10.1177/1535370219867262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Vitamin D activity is associated with the modulation of a wide variety of biological systems, in addition to its roles in calcium homeostatic mechanisms. While vitamin D is well known to promote gastrointestinal calcium absorption, vitamin D also plays a role in attenuating and/or preventing the progression of several gastrointestinal diseases including Crohn’s disease, ulcerative colitis, and colorectal cancer, and may also play a role in chemotherapy-induced intestinal mucositis. The pro-differentiation, immunomodulatory, and anti-inflammatory effects of vitamin D, which has been reported in numerous circumstances, are key potential mechanisms of action in the prevention of gastrointestinal disorders. While the debate of the effectiveness of vitamin D to treat bone pathologies continues, the clinical importance of vitamin D therapy to prevent gastrointestinal disorders should be investigated given current evidence, using both nutritional and pharmaceutical intervention approaches.Impact statementThe non-skeletal functions of vitamin D play an important role in health and disease. The anti-inflammatory properties and maintenance of intestinal function fulfilled by vitamin D impact other systems in the body though downstream processing. This review provides insight into the mechanisms underpinning the potential benefits of vitamin D in both maintaining intestinal homeostasis and associated diseased states.
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Affiliation(s)
| | - Paul H Anderson
- 1 School of Pharmacy and Medical Sciences, University of South Australia, Adelaide 5000, Australia
| | - Cyan L Sylvester
- 1 School of Pharmacy and Medical Sciences, University of South Australia, Adelaide 5000, Australia
| | - Andrea M Stringer
- 1 School of Pharmacy and Medical Sciences, University of South Australia, Adelaide 5000, Australia.,2 Adelaide Medical School, The University of Adelaide, Adelaide 5000, Australia
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65
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Vitamin D Receptor Signaling Regulates Craniofacial Cartilage Development in Zebrafish. J Dev Biol 2019; 7:jdb7020013. [PMID: 31234506 PMCID: PMC6630938 DOI: 10.3390/jdb7020013] [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] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 06/15/2019] [Accepted: 06/20/2019] [Indexed: 02/08/2023] Open
Abstract
Vitamin D plays essential roles in supporting the skeletal system. The active form of vitamin D functions through the vitamin D receptor (VDR). A hereditary vitamin-D-resistant rickets with facial dysmorphism has been reported, but the involvement of VDR signaling during early stages of craniofacial development remains to be elucidated. The present study investigated whether VDR signaling is implicated in zebrafish craniofacial cartilage development using a morpholino-based knockdown approach. Two paralogous VDR genes, vdra and vdrb, have been found in zebrafish embryos. Loss-of-vdra has no discernible effect on cartilage elements, whereas loss-of-vdrb causes reduction and malformation of craniofacial cartilages. Disrupting both vdra and vdrb leads to more severe defects or complete loss of cartilage. Notably, knockdown of vdrb results in elevated expression of follistatin a (fsta), a bone morphogenetic protein (BMP) antagonist, in the adjacent pharyngeal endoderm. Taken together, these findings strongly indicate that VDR signaling is required for early craniofacial cartilage development in zebrafish.
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66
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Lee JJ, Liu X, O'Neill D, Beggs MR, Weissgerber P, Flockerzi V, Chen XZ, Dimke H, Alexander RT. Activation of the calcium sensing receptor attenuates TRPV6-dependent intestinal calcium absorption. JCI Insight 2019; 5:128013. [PMID: 31013259 DOI: 10.1172/jci.insight.128013] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Plasma calcium (Ca2+) is maintained by amending the release of parathyroid hormone and through direct effects of the Ca2+ sensing receptor (CaSR) in the renal tubule. Combined, these mechanisms alter intestinal Ca2+ absorption by modulating 1,25-dihydroxy vitamin D3 production, bone resorption, and renal Ca2+ excretion. The CaSR is a therapeutic target in the treatment of secondary hyperparathyroidism and hypocalcemia a common complication of calcimimetic therapy. The CaSR is also expressed in intestinal epithelium, however, a direct role in regulating local intestinal Ca2+ absorption is unknown. Chronic CaSR activation decreased expression of genes involved in Ca2+ absorption. In Ussing chambers, increasing extracellular Ca2+ or basolateral application of the calcimimetic cinacalcet decreased net Ca2+ absorption across intestinal preparations acutely. Conversely, Ca2+ absorption increased with decreasing extracellular Ca2+ concentration. These responses were absent in mice expressing a non-functional TRPV6, TRPV6D541A. Cinacalcet also attenuated Ca2+ fluxes through TRPV6 in Xenopus oocytes when co-expressed with the CaSR. Moreover, the phospholipase C inhibitor, U73122, prevented cinacalcet-mediated inhibition of Ca2+ flux. These results reveal a regulatory pathway whereby activation of the CaSR in the basolateral membrane of the intestine directly attenuates local Ca2+ absorption via TRPV6 to prevent hypercalcemia and help explain how calcimimetics induce hypocalcemia.
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Affiliation(s)
- Justin J Lee
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada
| | - Xiong Liu
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Debbie O'Neill
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Megan R Beggs
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada
| | - Petra Weissgerber
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Hamburg, Germany
| | - Veit Flockerzi
- Experimentelle und Klinische Pharmakologie und Toxikologie, Saarland University, Hamburg, Germany
| | - Xing-Zhen Chen
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Henrik Dimke
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Nephrology, Odense University Hospital, Odense, Denmark
| | - R Todd Alexander
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada.,The Women's and Children's Health Research Institute, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
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67
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Ryan BA, Alhani K, Sellars KB, Kirby BJ, St-Arnaud R, Kaufmann M, Jones G, Kovacs CS. Mineral Homeostasis in Murine Fetuses Is Sensitive to Maternal Calcitriol but Not to Absence of Fetal Calcitriol. J Bone Miner Res 2019; 34:669-680. [PMID: 30508318 DOI: 10.1002/jbmr.3642] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 12/14/2022]
Abstract
Vitamin D receptor (VDR) null fetuses have normal serum minerals, parathyroid hormone (PTH), skeletal morphology, and mineralization but increased serum calcitriol, placental calcium transport, and placental expression of Pthrp, Trpv6, and (as reported in this study) Pdia3. We examined Cyp27b1 null fetal mice, which do not make calcitriol, to determine if loss of calcitriol has the same consequences as loss of VDR. Cyp27b1 null and wild-type (WT) females were mated to Cyp27b1+/- males, which generated Cyp27b1 null and Cyp27b1+/- fetuses from Cyp27b1 null mothers, and Cyp27b1+/- and WT fetuses from WT mothers. Cyp27b1 null fetuses had undetectable calcitriol but normal serum calcium and phosphorus, PTH, fibroblast growth factor 23 (FGF23), skeletal mineral content, tibial lengths and morphology, placental calcium transport, and expression of Trpv6 and Pthrp; conversely, placental Pdia3 was downregulated. However, although Cyp27b1+/- and null fetuses of Cyp27b1 null mothers were indistinguishable, they had higher serum and amniotic fluid calcium, lower amniotic fluid phosphorus, lower FGF23, and higher 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D than in WT and Cyp27b1+/- fetuses of WT mothers. In summary, loss of fetal calcitriol did not alter mineral or bone homeostasis, but Cyp27b1 null mothers altered mineral homeostasis in their fetuses independent of fetal genotype. Cyp27b1 null fetuses differ from Vdr null fetuses, possibly through high levels of calcitriol acting on Pdia3 in Vdr nulls to upregulate placental calcium transport and expression of Trpv6 and Pthrp. In conclusion, maternal calcitriol influences fetal mineral metabolism, whereas loss of fetal calcitriol does not. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Brittany A Ryan
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Canada
| | - Kamal Alhani
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Canada
| | - K Berit Sellars
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Canada
| | - Beth J Kirby
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Canada
| | - René St-Arnaud
- Shriners Hospitals for Children-Canada and McGill University, Montréal, Canada
| | | | | | - Christopher S Kovacs
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Canada
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68
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Li SH, Yin HB, Ren MR, Wu MJ, Huang XL, Li JJ, Luan YP, Wu YL. TRPV5 and TRPV6 are expressed in placenta and bone tissues during pregnancy in mice. Biotech Histochem 2019; 94:244-251. [PMID: 30916584 DOI: 10.1080/10520295.2018.1548710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
We investigated the dynamic expression of calcium transporters, TRPV5 and TRPV6, in placenta and bone to determine their role in maternal and fetal calcium balance during gestation. In placenta, TRPV5 was expressed predominantly in syncytiotrophoblasts of the labyrinthine zone, whereas TRPV6 was expressed in spongiotrophoblasts of the junction zone. In bone, the two transporters were found in osteoblasts, osteoclasts, cartilage and bone matrices. During the first half of gestation, TRPV5 and TRPV6 levels in bone were increased on pregnancy day (P) 0.5, then decreased on P3.5 followed by a slight increase on P6.5. During the second half of pregnancy, both the proteins and their mRNAs gradually increased from P9.5 to P15.5-P17.5 in both bone and placenta, followed at parturition by relatively high amounts in placenta, but markedly decreased amounts in bone. The expression pattern is likely related to the fetal and maternal calcium requirement during gestation, which may be regulated by estrogen and other hormones, because the fetal demand for calcium is greatest during the last few days of gestation for rats; maternal calcium metabolism is designed to meet the calcium needs of the fetus during this period. We found that TRPV5 and TRPV6 are involved in calcium transport in the placenta and bone, and therefore play a role in calcium homeostasis during embryonic and fetal development.
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Affiliation(s)
- S H Li
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
| | - H B Yin
- b Department of Animal Health Quarantine , Animal Disease Inspection and Supervision Institution of Yunnan Province , Kunming , Yunnan Province , P.R. China
| | - M R Ren
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
| | - M J Wu
- c School of Science and Health , Western Sydney University , Penrith , NSW , Australia
| | - X L Huang
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
| | - J J Li
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
| | - Y P Luan
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
| | - Y L Wu
- a College of Life Sciences , Southwest Forestry University , Kunming , Yunnan Province , P.R. China
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69
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Kawai M, Kinoshita S, Yamazaki M, Yamamoto K, Rosen CJ, Shimba S, Ozono K, Michigami T. Intestinal clock system regulates skeletal homeostasis. JCI Insight 2019; 4:121798. [PMID: 30730853 PMCID: PMC6483519 DOI: 10.1172/jci.insight.121798] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 01/30/2019] [Indexed: 12/14/2022] Open
Abstract
The circadian clock network is an evolutionarily conserved system involved in the regulation of metabolic homeostasis; however, its impacts on skeletal metabolism remain largely unknown. We herein demonstrated that the circadian clock network in the intestines plays pivotal roles in skeletal metabolism such that the lack of the Bmal1 gene in the intestines (Bmal1Int-/- mice) caused bone loss, with bone resorption being activated and bone formation suppressed. Mechanistically, Clock protein interaction with the vitamin D receptor (VDR) accelerated its binding to the VDR response element by enhancing histone acetylation in a circadian-dependent manner, and this was lost in Bmal1Int-/- mice because nuclear translocation of Clock required the presence of Bmal1. Accordingly, the rhythmic expression of VDR target genes involved in transcellular calcium (Ca) absorption was created, and this was not observed in Bmal1Int-/- mice. As a result, transcellular Ca absorption was impaired and bone resorption was activated in Bmal1Int-/- mice. Additionally, sympathetic tone, the activation of which suppresses bone formation, was elevated through afferent vagal nerves in Bmal1Int-/- mice, the blockade of which partially recovered bone loss by increasing bone formation and suppressing bone resorption in Bmal1Int-/- mice. These results demonstrate that the intestinal circadian system regulates skeletal bone homeostasis.
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Affiliation(s)
- Masanobu Kawai
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Izumi, Osaka, Japan
| | - Saori Kinoshita
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Izumi, Osaka, Japan
| | - Miwa Yamazaki
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Izumi, Osaka, Japan
| | - Keiko Yamamoto
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Izumi, Osaka, Japan
| | | | - Shigeki Shimba
- Department of Health Science, School of Pharmacy, Nihon University, Funabashi, Chiba, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Toshimi Michigami
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Izumi, Osaka, Japan
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Hansen KE, Nieves JW, Nudurupati S, Metz DC, Perez MC. Dexlansoprazole and Esomeprazole Do Not Affect Bone Homeostasis in Healthy Postmenopausal Women. Gastroenterology 2019; 156:926-934.e6. [PMID: 30445008 DOI: 10.1053/j.gastro.2018.11.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/06/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Epidemiological studies have associated proton pump inhibitor (PPI) therapy with osteoporotic fractures, but it is not clear if PPIs directly cause osteoporosis. We evaluated the effect of dexlansoprazole and esomeprazole on bone turnover, bone mineral density (BMD), true fractional calcium absorption (TFCA), serum and urine levels of minerals, and levels of parathyroid hormone (PTH) in healthy postmenopausal women. METHODS We performed a prospective, multicenter, double-blind study of 115 healthy, postmenopausal women (45 to 75 years of age) from November 4, 2010, through August 7, 2014. Women were randomly assigned to groups given dexlansoprazole (60 mg), esomeprazole (40 mg), or placebo daily for 26 weeks. We measured plasma levels of procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide of type 1 collagen (CTX) at 0 (baseline), 13, and 26 weeks. Primary outcomes were percent change in P1NP and CTX between weeks 0 and 26. We also measured changes in serum and urine levels of mineral, BMD, PTH (all subjects), and TFCA (n = 30). RESULTS Between baseline and week 26, there were no significant within-group differences in markers of bone turnover; there was a nonsignificant increase in CTX levels in the dexlansoprazole group (0.12 ng/mL). The esomeprazole and dexlansoprazole groups had significantly increased levels of P1NP (18.2% and 19.2%, respectively) and CTX (22.0% and 27.4%, respectively) at week 26 compared with the placebo group, although these values remained within normal ranges. There were no statistically significant differences between groups in serum or urine levels of minerals, BMD, or PTH at week 26. PPI therapy did not reduce TFCA. CONCLUSIONS In a prospective study of postmenopausal women, we found significant increases in markers of bone turnover in women given PPI therapy compared with women given placebo, but levels remained within the normal reference range. We found no significant differences among groups in changes in BMD, PTH, serum or urine levels of minerals, or TFCA. Our findings indicate that 26 weeks of treatment with a PPI has no clinically meaningful effects on bone homeostasis. Clinicaltrials.gov no: NCT01216293.
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Affiliation(s)
- Karen E Hansen
- School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin.
| | - Jeri W Nieves
- Mailman School of Public Health, Columbia University, New York, New York
| | - Sai Nudurupati
- Takeda Development Center Americas, Inc., Deerfield, Illinois
| | - David C Metz
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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Yamashita S, Mizumoto H, Sawada H, Suzuki Y, Hata D. TRPV6 Gene Mutation in a Dizygous Twin With Transient Neonatal Hyperparathyroidism. J Endocr Soc 2019; 3:602-606. [PMID: 30820485 PMCID: PMC6389352 DOI: 10.1210/js.2018-00374] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 12/28/2018] [Indexed: 01/27/2023] Open
Abstract
Maternal-fetal transport of calcium (Ca2+) is important for bone mineralization in fetal development. Insufficient Ca2+ transport causes transient neonatal hyperparathyroidism (TNHP). Transient receptor potential cation channel, subfamily V, member 6 (TRPV6), has been found to play an important role in the active transport of Ca2+ through the placenta. Recently, TRPV6 gene was found to be the gene responsible for TNHP with severe skeletal undermineralization. To date, only seven cases of TNHP caused by TRPV6 recessive mutations have been reported. We present a case of TNHP caused by TRPV6 gene mutations. A female newborn was hospitalized because of respiratory distress. Marked undermineralization of the skeleton was observed in X-ray imaging. Laboratory examination revealed markedly high PTH and absence of hypercalcemia along with vitamin D deficiency. Her twin brother presented with almost no symptoms. Maternal laboratory findings indicated normocalcemia, but vitamin D deficiency with a high PTH level for the lactation period was observed. We initially diagnosed the patient as having secondary hyperparathyroidism because of maternal vitamin D deficiency. Nevertheless, the reasons underlying the discordant clinical manifestations between the twin siblings remained unclear. Our analysis of TRPV6 gene clarified that the patient had compound heterozygote mutations, which were reported previously (p.Ile223Thr and p.Gly428Arg). Pathologic mutations in TRPV6 gene were not detected in the other sibling. The clinical symptoms in the patient were transient: they resolved during infancy. TNHP caused by TRPV6 gene mutations is a unique disease in terms of its transient pathology in utero and relief after birth.
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Affiliation(s)
- Sumie Yamashita
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
| | - Hiroshi Mizumoto
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
| | - Hirotake Sawada
- Division of Pediatrics, Department of Developmental and Urological-Reproductive Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Yoshiro Suzuki
- Division of Cell Signaling, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
| | - Daisuke Hata
- Department of Pediatrics, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
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Abstract
Vitamin D is a principal factor required for mineral and skeletal homeostasis. Vitamin D deficiency during development causes rickets and in adults can result in osteomalacia and increased risk of fracture. 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the hormonally active form of vitamin D, is responsible for the biological actions of vitamin D which are mediated by the vitamin D receptor (VDR). Mutations in the VDR result in early-onset rickets and low calcium and phosphate, indicating the essential role of 1,25(OH)2D3/VDR signaling in the regulation of mineral homeostasis and skeletal health. This chapter summarizes our current understanding of the production of the vitamin D endocrine hormone, 1,25(OH)2D3, and the actions of 1,25(OH)2D3 which result in the maintenance of skeletal homeostasis. The primary role of 1,25(OH)2D3 is to increase calcium absorption from the intestine and thus to increase the availability of calcium for bone mineralization. Specific actions of 1,25(OH)2D3 on the intestine, kidney, and bone needed to maintain calcium homeostasis are summarized, and the impact of vitamin D status on bone health is discussed.
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Affiliation(s)
- Sylvia Christakos
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA.
| | - Shanshan Li
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Jessica DeLa Cruz
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Lieve Verlinden
- Clinical and Experimental Medicine and Endocrinology, KU Leuven, Leuven, Belgium
| | - Geert Carmeliet
- Clinical and Experimental Medicine and Endocrinology, KU Leuven, Leuven, Belgium
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Zhang YG, Lu R, Xia Y, Zhou D, Petrof E, Claud EC, Sun J. Lack of Vitamin D Receptor Leads to Hyperfunction of Claudin-2 in Intestinal Inflammatory Responses. Inflamm Bowel Dis 2019; 25:97-110. [PMID: 30289450 PMCID: PMC6290786 DOI: 10.1093/ibd/izy292] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Vitamin D3 and vitamin D receptor (VDR) are involved in the pathogenesis of inflammatory bowel disease (IBD) and bacterial infection. Claudin-2 is a junction protein that mediates paracellular water transport in epithelia. Elevation of Claudin-2 is associated with active IBD. However, VDR involved in epithelial junctions under inflammation and infection remains largely unknown. We investigated the mechanisms on how VDR and Claudin-2 are related in inflamed states. METHODS Using cultured VDR-/- enteroids, human intestinal epithelial cells, VDR-/- mice with Salmonella- or DSS-colitis, and human IBD samples, we investigated the mechanisms how VDR and Claudin-2 are related in inflamed states. RESULTS After Salmonella infection had taken place, we observed significantly enhanced Claudin-2 and an increased bacterial invasion and translocation. A lack of VDR regulation led to a robust increase of Claudin-2 at the mRNA and protein levels post-infection. In DSS-treated VDR-/- mice, Claudin-2 was significantly increased. Location and quantification of Claudin-2 protein in the mouse colons treated with DSS also confirmed these results. Inflammatory cytokines were significantly higher in the serum and mRNA levels in intestine, which are known to increase Claudin-2. Furthermore, in inflamed intestine of ulcerative colitis patients, VDR expression was low and Claudin-2 was enhanced. Mechanistically, we identified the enhanced Claudin-2 promoter activity through the binding sites of NF-κB and STAT in inflamed VDR-/- cells. CONCLUSIONS Our studies have identified a new role for intestinal epithelial VDR in regulating barrier functions in the context of infection and inflammation.
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Affiliation(s)
- Yong-guo Zhang
- Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Rong Lu
- Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Yinglin Xia
- Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - David Zhou
- Department of Pathology, University of Rochester, Rochester, New York, USA,Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Elaine Petrof
- Department of Medicine, GI Diseases Research Unit and Division of Infectious Diseases, Queen’s University, Kingston, Ontario, Canada
| | - Erika C Claud
- Department of Pediatrics and Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Jun Sun
- Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA,Address correspondence to: Jun Sun, PhD, AGA Fellow, Professor Division of Gastroenterology and Hepatology Department of Medicine, University of Illinois at Chicago 840 S. Wood Street, Room 704 CSB, MC716 Chicago, IL, 60612, USA. E-mail:
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Sasaki S, Segawa H, Hanazaki A, Kirino R, Fujii T, Ikuta K, Noguchi M, Sasaki S, Koike M, Tanifuji K, Shiozaki Y, Kaneko I, Tatsumi S, Shimohata T, Kawai Y, Narisawa S, Millán JL, Miyamoto KI. A Role of Intestinal Alkaline Phosphatase 3 (Akp3) in Inorganic Phosphate Homeostasis. Kidney Blood Press Res 2018; 43:1409-1424. [PMID: 30212831 DOI: 10.1159/000493379] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 08/31/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND/AIMS Hyperphosphatemia is a serious complication of late-stage chronic kidney disease (CKD). Intestinal inorganic phosphate (Pi) handling plays an important role in Pi homeostasis in CKD. We investigated whether intestinal alkaline phosphatase 3 (Akp3), the enzyme that hydrolyzes dietary Pi compounds, is a target for the treatment of hyperphosphatemia in CKD. METHODS We investigated Pi homeostasis in Akp3 knockout mice (Akp3-/-). We also studied the progression of renal failure in an Akp3-/- mouse adenine treated renal failure model. Plasma, fecal, and urinary Pi and Ca concentration were measured with commercially available kit, and plasma fibroblast growth factor 23, parathyroid hormone, and 1,25(OH)2D3 concentration were measured with ELISA. Brush border membrane vesicles were prepared from mouse intestine using the Ca2+ precipitation method and used for Pi transport activity and alkaline phosphatase activity. In vivo intestinal Pi absorption was measured with oral 32P administration. RESULTS Akp3-/- mice exhibited reduced intestinal type II sodium-dependent Pi transporter (Npt2b) protein levels and Na-dependent Pi co-transport activity. In addition, plasma active vitamin D levels were significantly increased in Akp3-/- mice compared with wild-type animals. In the adenine-induced renal failure model, Akp3 gene deletion suppressed hyperphosphatemia. CONCLUSION The present findings indicate that intestinal Akp3 deletion affects Na+-dependent Pi transport in the small intestine. In the adenine-induced renal failure model, Akp3 is predicted to be a factor contributing to suppression of the plasma Pi concentration.
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Affiliation(s)
- Shohei Sasaki
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Hiroko Segawa
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima,
| | - Ai Hanazaki
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Ruri Kirino
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Toru Fujii
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Kayo Ikuta
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Miwa Noguchi
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Sumire Sasaki
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Megumi Koike
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Kazuya Tanifuji
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Yuji Shiozaki
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Ichiro Kaneko
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Sawako Tatsumi
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Takaaki Shimohata
- Department of Preventive Environment and Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Yoshichika Kawai
- Department of Food Science, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
| | - Sonoko Narisawa
- Sanford Children's Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - José Luis Millán
- Sanford Children's Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Ken-Ichi Miyamoto
- Department of Molecular Nutrition, Institute of Biomedical Sciences, University of Tokushima Graduate School, Tokushima, Japan
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Vitamin D receptor suppresses proliferation and metastasis in renal cell carcinoma cell lines via regulating the expression of the epithelial Ca2+ channel TRPV5. PLoS One 2018; 13:e0195844. [PMID: 29659618 PMCID: PMC5901920 DOI: 10.1371/journal.pone.0195844] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 04/01/2018] [Indexed: 02/05/2023] Open
Abstract
We previously demonstrated that transient receptor potential vanilloid subfamily 5 (TRPV5) expression was decreased in renal cell carcinoma (RCC) compared with that in normal kidney tissues, a finding that was correlated with vitamin D receptor (VDR) expression, but further investigations is warranted. The aim of this study was to elucidate whether VDR could regulate the expression of TRPV5 and affect proliferation and metastasis in RCC. In this study, we used lentivirus to conduct the model of VDR overexpression and knockdown caki-1 and 786-O RCC cell lines in vitro. The results demonstrated that VDR overexpression significantly inhibited RCC cells proliferation, migration and invasion, and promoted apoptosis by the MTT, transwell cell migration/invasion and flow cytometry assays, respectively. However, VDR knockdown in RCC cells had the opposite effect. The RNA-sequence assay, which was assessed in caki-1 cells after VDR overexpression and knockdown, also indicated that significantly differentially expressed genes were associated with cell apoptotic, differentiation, proliferation and migration. RT-PCR and western blot analysis showed that VDR knockdown increased TRPV5 expression and VDR overexpression decreased TRPV5 expression in caki-1 cells. Furthermore, knockdown of TRPV5 expression suppressed the VDR knockdown-induced change in the proliferation, migration and invasion in caki-1 cells. Taken together, these findings confirmed that VDR functions as a tumour suppressor in RCC cells and suppresses the proliferation, migration and invasion of RCC through regulating the expression of TRPV5.
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Lee SM, Meyer MB, Benkusky NA, O'Brien CA, Pike JW. The impact of VDR expression and regulation in vivo. J Steroid Biochem Mol Biol 2018; 177:36-45. [PMID: 28602960 PMCID: PMC5723236 DOI: 10.1016/j.jsbmb.2017.06.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/02/2017] [Accepted: 06/05/2017] [Indexed: 12/23/2022]
Abstract
The vitamin D receptor (VDR) mediates the pleiotropic biological actions of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). These actions include orchestration of mineral homeostasis which is coordinated by the kidney, intestine, bone and parathyroid gland wherein the VDR transcriptionally regulates expression of the genes involved in this complex process. Mutations in human VDR (hVDR) cause hereditary vitamin D resistant rickets, a genetic syndrome characterized by hypocalcemia, hyperparathyroidism and rickets resulting from dysregulation of mineral homeostasis. Expression of the VDR is regulated by external stimuli in a tissue-specific manner. However, the mechanisms of this tissue-specificity remain unclear. Studies also suggest that phosphorylation of hVDR at serine 208 impacts the receptor's transcriptional activity. These experiments were conducted in vitro, however, and therefore limited in their conclusions. In this report, we summarize (1) our most recently updated ChIP-seq data from mouse tissues to identify regulatory regions responsible for the tissues-specific regulation of the VDR and (2) our studies to understand the mechanism of hormonal regulation of Vdr expression in bone and kidney in vivo using transgenic mouse strains generated by mouse mini-genes that contain comprehensive genetic information capable of recapitulating endogenous Vdr gene regulation and expression. We also defined the functional human VDR gene locus in vivo by using a human mini-gene comparable to that in the mouse to generate a humanized VDR mouse strain in which the receptor is expressed at normal levels (normal expressor). The present report also shows that a humanized mouse model in which the VDR is expressed at levels about 10-fold lower than the normal expressor mouse rescued the VDR-null phenotype despite its reduced transcriptional activity relative to wildtype expression. We also generated an additional humanized mouse model expressing hVDR bearing a mutation converting serine 208 to alanine (hVDR-S208A). In spite of the mutation, target gene expression induced by the ligand was unchanged relative to a mouse strain expressing comparable levels of wildtype hVDR. Further characterization also showed that serum calcium and parathyroid hormone levels were normal and alopecia was not observed in this hVDR-S208A mouse strain as well. Taken together, our in vivo studies using ChIP-seq analyses and the mini-gene transgenic mice improve our understanding of the tissue-specific regulatory mechanisms of controlling VDR expression and the mechanisms of action of the VDR.
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Affiliation(s)
- Seong Min Lee
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Mark B Meyer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Nancy A Benkusky
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Charles A O'Brien
- University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - J Wesley Pike
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States.
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Starczak Y, Reinke DC, Barratt KR, Ryan JW, Russell PK, Clarke MV, St-Arnaud R, Morris HA, Davey RA, Atkins GJ, Anderson PH. Absence of vitamin D receptor in mature osteoclasts results in altered osteoclastic activity and bone loss. J Steroid Biochem Mol Biol 2018; 177:77-82. [PMID: 29107736 DOI: 10.1016/j.jsbmb.2017.10.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 10/24/2017] [Accepted: 10/26/2017] [Indexed: 11/29/2022]
Abstract
Mature osteoclasts express the vitamin D receptor (VDR) and are able to synthesise and respond to 1,25(OH)2D3 via CYP27B1 enzyme activity. Whether vitamin D signalling within osteoclasts is necessary for the regulation of osteoclastic bone resorption in an in vivo setting is unclear. To determine the requirement for the VDR- and CYP27B1-mediated activity in mature osteoclasts, conditional deletion mouse models were created whereby either Vdr or Cyp27b1 gene was inactivated by breeding either Vdrfl/fl or Cyp27b1fl/fl mice with Cathepsin K-Cre transgenic mice (CstkCre) to generate CtskCre/Vdr-/- and CtskCre/Cyp27b1-/- mice respectively. To account for potential CtskCre-meaited off-target deletion of Vdr, Dmp1Cre were also used determine the effect of Vdr deletion in osteocytes. Furthermore, CtskCre/Vdr-/- mice were ovariectomised (OVX) to assess the role of VDR in osteoclasts under bone-loss conditions and bone marrow precursor cells were cultured under osteoclastogenic conditions to assess osteoclast formation. Six-week-old CtskCre/Vdr-/- female mice demonstrated a 15% decrease in femoral BV/TV (p<0.05). In contrast, BV/TV remained unchanged in CtskCre/Cyp27b1-/- mice as well as in Dmp1Cre/VDR-/- mice. When CtskCre/Vdr-/- mice were subjected to OVX, the bone loss that occurred in CtskCre/Vdr-/- was predominantly due to a diminished volume of thinner trabeculae when compared to control levels. These changes in bone volume in CtskCre/Vdr-/- mice occurred without an observable histological change in osteoclast numbers or size. However, while cultured bone marrow-derived osteoclasts from CtskCre/Vdr-/- mice were marginally increased when compared to VDRfl/fl mice, elevated expression of genes such as Cathepsin K, Nfatc1 and VATPase was observed. Collectively, these data indicate that the absence of VDR in mature osteoclasts causes exacerbated bone loss in young mice and during OVX which is associated with enhanced osteoclastic activity and without increased osteoclastogenesis.
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Affiliation(s)
- Yolandi Starczak
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5005, Australia
| | - Daniel C Reinke
- Biomedical Orthopaedic Research Group, Centre for Orthopaedic & Trauma Research, University of Adelaide, Australia
| | - Kate R Barratt
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5005, Australia
| | - Jackson W Ryan
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5005, Australia
| | - Patricia K Russell
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Michele V Clarke
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - René St-Arnaud
- Department of Surgery and Human Genetics, McGill University, Montreal, Quebec, Canada; Research Centre, Shriners Hospitals for Children, Montreal, Quebec, Canada
| | - Howard A Morris
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5005, Australia
| | - Rachel A Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Gerald J Atkins
- Biomedical Orthopaedic Research Group, Centre for Orthopaedic & Trauma Research, University of Adelaide, Australia
| | - Paul H Anderson
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5005, Australia.
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Uekawa A, Yamanaka H, Lieben L, Kimira Y, Uehara M, Yamamoto Y, Kato S, Ito K, Carmeliet G, Masuyama R. Phosphate-dependent luminal ATP metabolism regulates transcellular calcium transport in intestinal epithelial cells. FASEB J 2018; 32:1903-1915. [PMID: 29282249 DOI: 10.1096/fj.201700631r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Extracellular low phosphate strongly enhances intestinal calcium absorption independently of active vitamin D [1,25(OH)2D3] signaling, but the underlying mechanisms remain poorly characterized. To elucidate the phosphate-dependent regulation of calcium transport, we investigated part of the enteral environment that is involved in 1,25(OH)2D3-independent calcium absorption, which responds to dietary phosphate levels in mice that lack intestinal vitamin D receptor ( Vdr) activity. Impaired calcium absorption in intestinal Vdr-null mice was improved by dietary phosphate restriction. Accordingly, calcium transport in cultured intestinal epithelial cells was increased when the apical side was exposed to low phosphate levels (0.5 mM) compared with normal or high phosphate levels (1.0 or 5.0 mM, respectively). Mechanistically, low phosphate increased ATP in the apical side medium and allowed calcium entry into epithelial cells via the P2X7 purinoreceptor, which results in increased calcium transport. We found that luminal ATP was regulated by the release and degradation of ATP at the epithelium, and phosphate restriction increased ATP release from epithelial cells via connexin-43 hemichannels. Furthermore, ATP degradation by ectonucleotide pyrophosphatase-1 was reduced, which was caused by the reduction of the MAPK cascade. These findings indicate that luminal ATP metabolism regulates transcellular calcium transport in the intestine by an 1,25(OH)2D3-independent mechanism in response to dietary phosphate levels.-Uekawa, A., Yamanaka, H., Lieben, L., Kimira, Y., Uehara, M., Yamamoto, Y., Kato, S., Ito, K., Carmeliet, G., Masuyama, R. Phosphate-dependent luminal ATP metabolism regulates transcellular calcium transport in intestinal epithelial cells.
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Affiliation(s)
- Atsushi Uekawa
- Department of Molecular Bone Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Hitoki Yamanaka
- Center for Frontier Life Sciences, Nagasaki University, Nagasaki, Japan
| | - Liesbet Lieben
- Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Yoshifumi Kimira
- Department of Nutritional Science, Tokyo University of Agriculture, Tokyo, Japan
| | - Mariko Uehara
- Department of Nutritional Science, Tokyo University of Agriculture, Tokyo, Japan
| | - Yoko Yamamoto
- Surgical Oncology and Vascular Surgery, University of Tokyo, Tokyo, Japan
| | - Shigeaki Kato
- Research Institute of Innovative Medicine, Tokiwa Foundation, Iwaki, Fukushima, Japan
| | - Kosei Ito
- Department of Molecular Bone Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Geert Carmeliet
- Clinical and Experimental Endocrinology, KU Leuven, Leuven, Belgium
| | - Ritsuko Masuyama
- Department of Molecular Bone Biology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
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79
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Miratashi Yazdi SA, Abbasi M, Miratashi Yazdi SM. Epilepsy and vitamin D: a comprehensive review of current knowledge. Rev Neurosci 2018; 28:185-201. [PMID: 27988507 DOI: 10.1515/revneuro-2016-0044] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/24/2016] [Indexed: 12/29/2022]
Abstract
Vitamin D has been considered as neurosteroid, and its pivotal role in neuroprotection, brain development, and immunomodulation has been noticed in studies; however, our knowledge regarding its role in neurological disorders is still developing. The potential role of vitamin D in the pathophysiology and treatment of epilepsy, as one the most prevalent neurological disorders, has received less attention in recent years. In this article, we review the possible relationship between vitamin D and epilepsy from different aspects, including the action mechanism of vitamin D in the central nervous system and ecological and epidemiological findings. We also present the outcome of studies that evaluated the level of vitamin D and the impact of administrating vitamin D in epileptic patients or animal subjects. We also review the current evidence on interactions between vitamin D and antiepileptic drugs.
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80
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Carmeliet G, Bouillon R. How Important Is Vitamin D for Calcium Homeostasis During Pregnancy and Lactation? J Bone Miner Res 2018; 33:13-15. [PMID: 29165840 DOI: 10.1002/jbmr.3344] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 11/18/2017] [Accepted: 11/20/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| | - Roger Bouillon
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases, Metabolism and Ageing, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
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81
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Abstract
The vitamin D receptor (VDR) binds the secosteroid hormone 1,25(OH)2D3 with high affinity and regulates gene programs that control a serum calcium levels, as well as cell proliferation and differentiation. A significant focus has been to exploit the VDR in cancer settings. Although preclinical studies have been strongly encouraging, to date clinical trials have delivered equivocal findings that have paused the clinical translation of these compounds. However, it is entirely possible that mining of genomic data will help to refine precisely what are the key anticancer actions of vitamin D compounds and where these can be used most effectively.
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Affiliation(s)
- Moray J Campbell
- Division of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, The Ohio State University, 536 Parks Hall, Columbus, OH 43210, USA.
| | - Donald L Trump
- Department of Medicine, Inova Schar Cancer Institute, Virginia Commonwealth University, 3221 Gallows Road, Fairfax, VA 22031, USA
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82
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Yang H, Ahn C, Shin EK, Lee JS, An BS, Jeung EB. NCKX3 was compensated by calcium transporting genes and bone resorption in a NCKX3 KO mouse model. Mol Cell Endocrinol 2017; 454:93-102. [PMID: 28602864 DOI: 10.1016/j.mce.2017.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 05/18/2017] [Accepted: 06/06/2017] [Indexed: 01/10/2023]
Abstract
Gene knockout is the most powerful tool for determination of gene function or permanent modification of the phenotypic characteristics of an animal. Existing methods for gene disruption are limited by their efficiency, time required for completion and potential for confounding off-target effects. In this study, a rapid single-step approach to knockout of a targeted gene in mice using zinc-finger nucleases (ZFNs) was demonstrated for generation of mutant (knockout; KO) alleles. Specifically, ZFNs to target the sodium/calcium/potassium exchanger3 (NCKX3) gene in C57bl/6j were designed using the concept of this approach. NCKX3 KO mice were generated and the phenotypic characterization and molecular regulation of active calcium transporting genes was assessed when mice were fed different calcium diets during growth. General phenotypes such as body weight and plasma ion level showed no distinct abnormalities. Thus, the potassium/sodium/calcium exchanger of NCKX3 KO mice proceeded normally in this study. As a result, the compensatory molecular regulation of this mechanism was elucidated. Renal TRPV5 mRNA of NCKX3 KO mice increased in both male and female mice. Expression of TRPV6 mRNA was only down-regulated in the duodenum of male KO mice. Renal- and duodenal expression of PTHR and VDR were not changed; however, GR mRNA expression was increased in the kidney of NCKX3 KO mice. Depletion of the NCKX3 gene in a KO mouse model showed loss of bone mineral contents and increased plasma parathyroid hormone, suggesting that NCKX3 may play a role in regulating calcium homeostasis.
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Affiliation(s)
- Hyun Yang
- Laboratory of Veterinary Biochemistry and Molecular Biology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea; Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Republic of Korea
| | - Changhwan Ahn
- Laboratory of Veterinary Biochemistry and Molecular Biology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Eun-Kyeong Shin
- Laboratory of Veterinary Biochemistry and Molecular Biology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Ji-Sun Lee
- Laboratory of Veterinary Biochemistry and Molecular Biology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Beum-Soo An
- Department of Biomaterials Science, College of National Resources & Life Science, Pusan National University, Miryang, Gyeongsangnam-do 627-706, Republic of Korea
| | - Eui-Bae Jeung
- Laboratory of Veterinary Biochemistry and Molecular Biology, Veterinary Medical Center and College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea.
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83
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Hou T, Liu Y, Guo D, Li B, He H. Collagen Peptides from Crucian Skin Improve Calcium Bioavailability and Structural Characterization by HPLC-ESI-MS/MS. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:8847-8854. [PMID: 28915036 DOI: 10.1021/acs.jafc.7b03059] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The effects of collagen peptides (CPs), which are derived from crucian skin, were investigated in a retinoic acid-induced bone loss model. The level of serum bone alkaline phosphatase (BALP) in the model group (117.65 ± 4.66 units/L) was significantly higher than those of the other three groups (P < 0.05). After treatment with 600 and 1200 mg of CPs/kg, the level of BALP decreased to 85.26 ± 7.35 and 97.03 ± 7.21 units/L, respectively. After treatment with 600 mg of CPs/kg, the bone calcium content significantly increased by 22% (femur) and 12.38% (tibia) compared to those of the model group. In addition, the bone mineral density in the 600 mg of CPs/kg group was significantly higher (femur, 0.37 ± 0.02 g/cm2; tibia, 0.33 ± 0.02 g/cm2) than in the model group (femur, 0.26 ± 0.01 g/cm2; tibia, 0.23 ± 0.02 g/cm2). The morphology results indicated bone structure improved after the treatment with CPs. Structural characterization demonstrated that Glu, Lys, and Arg play important roles in binding calcium and promoting calcium uptake. Our results indicated that CPs could promote calcium uptake and regulate bone formation.
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Affiliation(s)
- Tao Hou
- College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education , Wuhan 43000, China
| | - Yanshuang Liu
- College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education , Wuhan 43000, China
| | - Danjun Guo
- College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education , Wuhan 43000, China
| | - Bo Li
- College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education , Wuhan 43000, China
| | - Hui He
- College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China
- Key Laboratory of Environment Correlative Dietology (Huazhong Agricultural University), Ministry of Education , Wuhan 43000, China
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84
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Schafer AL. Vitamin D and intestinal calcium transport after bariatric surgery. J Steroid Biochem Mol Biol 2017; 173:202-210. [PMID: 28027914 PMCID: PMC5483209 DOI: 10.1016/j.jsbmb.2016.12.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 12/14/2022]
Abstract
Bariatric surgery is a highly effective treatment for obesity, but it may have detrimental effects on the skeleton. Skeletal effects are multifactorial but mediated in part by nutrient malabsorption. While there is increasing interest in non-nutritional mechanisms such as changes in fat-derived and gut-derived hormones, nutritional factors are modifiable and thus represent potential opportunities to prevent and treat skeletal complications. This review begins with a discussion of normal intestinal calcium transport, including recent advances in our understanding of its regulation by vitamin D, and areas of continued uncertainty. Human and animal studies of vitamin D and intestinal calcium transport after bariatric surgery are then summarized. In humans, even with optimized 25-hydroxyvitamin D levels and recommended calcium intake, fractional calcium absorption decreased dramatically after Roux-en-Y gastric bypass (RYGB). In rats, intestinal calcium absorption was lower after RYGB than after sham surgery, despite elevated 1,25-dihyroxyvitamin D levels and intestinal gene expression evidence of vitamin D responsiveness. Such studies have the potential to shed new light on the physiology of vitamin D and intestinal calcium transport. Moreover, understanding the effects of bariatric surgery on these processes may improve the clinical care of bariatric surgery patients.
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Affiliation(s)
- Anne L Schafer
- Endocrine Research Unit, San Francisco Veterans Affairs Health Care System, United States; Departments of Medicine and of Epidemiology & Biostatistics, University of California, San Francisco, United States.
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85
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Fleet JC. The role of vitamin D in the endocrinology controlling calcium homeostasis. Mol Cell Endocrinol 2017; 453:36-45. [PMID: 28400273 PMCID: PMC5529228 DOI: 10.1016/j.mce.2017.04.008] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/07/2017] [Accepted: 04/08/2017] [Indexed: 12/14/2022]
Abstract
Vitamin D and its' metabolites are a crucial part of the endocrine system that controls whole body calcium homeostasis. The goal of this hormonal control is to regulate serum calcium levels so that they are maintained within a very narrow range. To achieve this goal, regulatory events occur in coordination at multiple tissues, e.g. the intestine, kidney, bone, and parathyroid gland. Production of the vitamin D endocrine hormone, 1,25 dihydroxyvitamin D (1,25(OH)2 D) is regulated by habitual dietary calcium intake and physiologic states like growth, aging, and the menopause. The molecular actions of 1,25(OH)2 D on calcium regulating target tissues are mediated predominantly by transcription controlled by the vitamin D receptor. A primary role for 1,25(OH)2 D during growth is to increase intestinal calcium absorption so that sufficient calcium is available for bone mineralization. However, vitamin D also has specific actions on kidney and bone.
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Affiliation(s)
- James C Fleet
- Department of Nutrition Science, Room G1B Stone Hall, Purdue University, West Lafayette, IN 47907-2059, United States.
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86
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Ishizawa M, Akagi D, Yamamoto J, Makishima M. 1α,25-Dihydroxyvitamin D 3 enhances TRPV6 transcription through p38 MAPK activation and GADD45 expression. J Steroid Biochem Mol Biol 2017; 172:55-61. [PMID: 28578001 DOI: 10.1016/j.jsbmb.2017.05.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 05/25/2017] [Accepted: 05/28/2017] [Indexed: 01/01/2023]
Abstract
The active form of vitamin D, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], acts as a ligand for the vitamin D receptor (VDR), and regulates various physiological processes, including calcium and bone metabolism, cellular growth and differentiation, immunity and cardiovascular function. A number of vitamin D derivatives have been synthesized for the treatment of cancer and inflammatory disease, but the adverse effect of hypercalcemic activity due to intestinal calcium absorption has limited wide clinical application. The VDR target gene product TRPV6 is essential for intestinal calcium absorption. Our prior study has demonstrated that 1,25(OH)2D3 induces TRPV6 mRNA expression at lower concentrations than for induction of CYP24A1, a VDR target gene involved in vitamin D inactivation, in intestinal SW480 cells, suggesting an additional mechanism for vitamin D signaling on TRPV6 induction. By searching for a signal transduction pathway involved in 1,25(OH)2D3-induced expression of TRPV6, we found that a p38 mitogen-activated protein kinase (MAPK) inhibitor reduces the expression of TRPV6 but not CYP24A1 in 1,25(OH)2D3-treated SW480 cells. Knockdown experiments showed that p38α is involved in 1,25(OH)2D3-induced expression of TRPV6 but not CYP24A1. Treatment with a de novo protein synthesis inhibitor suppressed 1,25(OH)2D3-induced TRPV6 expression. Finally, we found that 1,25(OH)2D3 treatment induced expression of GADD45A, which encodes the GADD45α MAPK kinase kinase activator, earlier than TRPV6 expression and that GADD45A knockdown reduced TRPV6 induction by 1,25(OH)2D3. These findings indicate that p38α and GADD45α are involved in an enhanced vitamin D signaling on TRPV6 expression.
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Affiliation(s)
- Michiyasu Ishizawa
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Daisuke Akagi
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan; Department of Applied Biological Science, Nihon University College of Bioresource Sciences, Fujisawa, Kanagawa 252-8510, Japan
| | - Jumpei Yamamoto
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan; Department of Applied Biological Science, Nihon University College of Bioresource Sciences, Fujisawa, Kanagawa 252-8510, Japan
| | - Makoto Makishima
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan.
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87
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Identification of Novel Non-secosteroidal Vitamin D Receptor Agonists with Potent Cardioprotective Effects and devoid of Hypercalcemia. Sci Rep 2017; 7:8427. [PMID: 28814738 PMCID: PMC5559458 DOI: 10.1038/s41598-017-08670-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 07/12/2017] [Indexed: 12/22/2022] Open
Abstract
Vitamin D regulates many biological processes, but its clinical utility is limited by its hypercalcemic effect. Using a virtual screening platform to search novel chemical probes that activate the vitamin D signaling, we report discovery of novel non-steroidal small-molecule compounds that activate the vitamin D receptor (VDR), but are devoid of hypercalcemia. A lead compound (known as VDR 4-1) demonstrated potent transcriptional activities in a VDR reporter gene assay, and significantly ameliorated cardiac hypertrophy in cell culture studies and in animal models. VDR 4-1 also effectively suppressed secondary hyperparathyroidism in 1α-hydroxylase knockout mice. In contrast to 1α,25-dihydroxyvitamin D3 (1,25-D3 or calcitriol), a naturally occurring VDR agonist, VDR 4-1 therapy even at high doses did not induce hypercalcemia. These findings were accompanied by a lack of upregulation of calcium transport genes in kidney and in the gut providing a mechanism for the lack of hypercalcemia. Furthermore, VDR 4-1 therapy significantly suppressed cardiac hypertrophy and progression to heart failure in both vitamin D deficient and normal mice without inducing significant hypercalcemia. In conclusion, we have identified a unique VDR agonist compound with beneficial effects in mouse models of hyperparathyroidism and heart failure without inducing significant hypercalcemia.
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88
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Kawaguchi K, Yoshida S, Hatano R, Asano S. Pathophysiological Roles of Ezrin/Radixin/Moesin Proteins. Biol Pharm Bull 2017; 40:381-390. [PMID: 28381792 DOI: 10.1248/bpb.b16-01011] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ezrin/radixin/moesin (ERM) proteins function as general cross-linkers between plasma membrane proteins and the actin cytoskeleton and are involved in the functional expression of membrane proteins on the cell surface. They also integrate Rho guanosine 5'-triphosphatase (GTPase) signaling to regulate cytoskeletal organization by sequestering Rho-related proteins. They act as protein kinase A (PKA)-anchoring proteins and sequester PKA close to its target proteins for their effective phosphorylation and functional regulation. Therefore, ERM proteins seem to play important roles in the membrane transport of electrolytes by ion channels and transporters. In this review, we focus on the pathophysiological roles of ERM proteins in in vivo studies and introduce the phenotypes of their knockout and knockdown mice.
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Affiliation(s)
- Kotoku Kawaguchi
- Department of Molecular Physiology, College of Pharmaceutical Sciences, Ritsumeikan University
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89
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Intra-Amniotic Administration (Gallus gallus) of Cicer arietinum and Lens culinaris Prebiotics Extracts and Duck Egg White Peptides Affects Calcium Status and Intestinal Functionality. Nutrients 2017; 9:nu9070785. [PMID: 28754012 PMCID: PMC5537899 DOI: 10.3390/nu9070785] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/29/2017] [Accepted: 07/19/2017] [Indexed: 12/13/2022] Open
Abstract
Calcium (Ca) is one of the most abundant inorganic elements in the human body and has many important physiological roles. Prebiotics and bioactive peptides are two important substances used to promote calcium uptake. However, the difference in mechanisms of the calcium uptake from these two supplements is not clear. By using the Gallus gallus model and the intra-amniotic administration procedure, the aim of this study was to investigate whether Ca status, intestinal functionality, and health-promoting bacterial populations were affected by prebiotics extracted from chickpea and lentil, and duck egg white peptides (DPs). Eleven groups (non-injected; 18 MΩ H2O; 4 mmol/L CaCl2; 50 mg/mL chickpea + 4 mmol/L CaCl2; 50 mg/mL lentil + 4 mmol/L CaCl2; 40 mg/mL DPs + 4 mmol/L CaCl2; 5 mg/mL Val-Ser-Glu-Glu (VSEE) + 4 mmol/L CaCl2; 50 mg/mL chickpea; 50 mg/mL lentil; 40 mg/mL DPs; 5 mg/mL VSEE) were utilized. Upon hatch, blood, cecum, small intestine, liver and bone were collected for assessment of serum bone alkaline phosphate level (BALP), the relative abundance of intestinal microflora, expression of Ca-related genes, brush border membrane (BBM) functional genes, and liver and bone mineral levels, respectively. The BALP level increased in the presence of lentil, DPs and VSEE (p < 0.05). The relative abundance of probiotics increased significantly (p < 0.05) by VSEE + Ca and chickpea. The expression of CalbindinD9k (Ca transporter) increased (p < 0.05) in Ca, chickpea + Ca and lentil + Ca groups. In addition, the brush border membrane functionality genes expressions increased (p < 0.05) by the chickpea or lentil extracts. Prebiotics and DPs beneficially affected the intestinal microflora and duodenal villus surface area. This research expands the understanding of the prebiotics’ properties of chickpea and lentil extracts, and peptides’ effects on calcium metabolism and gut health.
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90
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Silvagno F, Pescarmona G. Spotlight on vitamin D receptor, lipid metabolism and mitochondria: Some preliminary emerging issues. Mol Cell Endocrinol 2017; 450:24-31. [PMID: 28414049 DOI: 10.1016/j.mce.2017.04.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/07/2017] [Accepted: 04/09/2017] [Indexed: 12/19/2022]
Abstract
Transcriptional control and modulation of calcium fluxes underpin the differentiating properties of vitamin D (1,25(OH)2D3). In the latest years however few studies have pointed out the relevance of the mitochondrial effects of the hormone. It is now time to focus on the metabolic results of vitamin D receptor (VDR) action in mitochondria, which can explain the pleiotropic effects of 1,25(OH)2D3 and may elucidate few contrasting aspects of its activity. The perturbation of lipid metabolism described in VDR knockout mice and vitamin D deficient animals can be revisited based on the newly identified mechanism of action of 1,25(OH)2D3 in mitochondria. From the same point of view, the controversial role of 1,25(OH)2D3 in adipogenesis can be better interpreted.
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Affiliation(s)
- Francesca Silvagno
- Department of Oncology, University of Torino, Via Santena 5 bis, 10126 Torino, Italy.
| | - Gianpiero Pescarmona
- Department of Oncology, University of Torino, Via Santena 5 bis, 10126 Torino, Italy.
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91
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Leyssens C, Verlinden L, De Hertogh G, Kato S, Gysemans C, Mathieu C, Carmeliet G, Verstuyf A. Impact on Experimental Colitis of Vitamin D Receptor Deletion in Intestinal Epithelial or Myeloid Cells. Endocrinology 2017; 158:2354-2366. [PMID: 28472309 DOI: 10.1210/en.2017-00139] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 04/26/2017] [Indexed: 12/13/2022]
Abstract
Inflammatory bowel diseases are gastrointestinal diseases that include Crohn disease and ulcerative colitis. The chronic inflammation is thought to result from an excessive inflammatory response to environmental factors such as luminal bacteria in genetically predisposed individuals. Studies have revealed that mice with impaired vitamin D signaling are more susceptible to experimental colitis. To better understand the contribution of vitamin D signaling in different cells of the gut to this disease, we investigated the effects of intestinal-specific or myeloid vitamin D receptor deletion. Our study addressed the importance of vitamin D receptor expression in intestinal epithelial cells using intestine-specific vitamin D receptor null mice and the contribution of vitamin D receptor expression in macrophages and granulocytes using myeloid-specific vitamin D receptor null mice in a dextran sodium sulfate model for experimental colitis. Loss of intestinal vitamin D receptor expression had no substantial effect on the clinical parameters of colitis and did not manifestly change mucosal cytokine expression. Inactivation of the vitamin D receptor in macrophages and granulocytes marginally affected colitis-associated symptoms but resulted in increased proinflammatory cytokine and increased β-defensin-1 expression in the colon descendens of mice with colitis. Intestinal deletion of the vitamin D receptor did not aggravate symptoms of chemically induced colitis. Loss of the vitamin D receptor in macrophages and granulocytes mildly affected colitis-associated symptoms but greatly increased proinflammatory cytokine expression in the inflamed colon, suggesting a prominent role for innate immune cell vitamin D signaling in controlling gut inflammation.
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Affiliation(s)
- Carlien Leyssens
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
| | - Lieve Verlinden
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
| | - Gert De Hertogh
- Translational Cell and Tissue Research, University of Leuven, Leuven 3000, Belgium
| | - Shigeaki Kato
- Research Institute of Innovative Medicine, Tokiwa Foundation, Iwaki 972-8322, Japan
| | - Conny Gysemans
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
| | - Chantal Mathieu
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
| | - Annemieke Verstuyf
- Laboratory of Clinical and Experimental Endocrinology, University of Leuven, Leuven 3000, Belgium
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92
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Beggs MR, Alexander RT. Intestinal absorption and renal reabsorption of calcium throughout postnatal development. Exp Biol Med (Maywood) 2017; 242:840-849. [PMID: 28346014 DOI: 10.1177/1535370217699536] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Calcium is vital for many physiological functions including bone mineralization. Postnatal deposition of calcium into bone is greatest in infancy and continues through childhood and adolescence until peek mineral density is reached in early adulthood. Thereafter, bone mineral density remains static until it eventually declines in later life. A positive calcium balance, i.e. more calcium absorbed than excreted, is crucial to bone deposition during growth and thus to peek bone mineral density. Dietary calcium is absorbed from the intestine into the blood. It is then filtered by the renal glomerulus and either reabsorbed by the tubule or excreted in the urine. Calcium can be (re)absorbed across intestinal and renal epithelia via both transcellular and paracellular pathways. Current evidence suggests that significant intestinal and renal calcium transport changes occur throughout development. However, the molecular details of these alterations are incompletely delineated. Here we first briefly review the current model of calcium transport in the intestine and renal tubule in the adult. Then, we describe what is known with regard to calcium handling through postnatal development, and how alterations may aid in mediating a positive calcium balance. The role of transcellular and paracellular calcium transport pathways and the contribution of specific intestinal and tubular segments vary with age. However, the current literature highlights knowledge gaps in how specifically intestinal and renal calcium (re)absorption occurs early in postnatal development. Future research should clarify the specific changes in calcium transport throughout early postnatal development including mediators of these alterations enabling appropriate bone mineralization. Impact statement This mini review outlines the current state of knowledge pertaining to the molecules and mechanisms maintaining a positive calcium balance throughout postnatal development. This process is essential to achieving optimal bone mineral density in early adulthood, thereby lowering the lifetime risk of osteoporosis.
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Affiliation(s)
- Megan R Beggs
- 1 Department of Physiology, University of Alberta, Edmonton, Alberta T6G 2R7, Canada
| | - R Todd Alexander
- 1 Department of Physiology, University of Alberta, Edmonton, Alberta T6G 2R7, Canada.,2 Department of Pediatrics, University of Alberta, Edmonton, Alberta T6G 2R7, Canada
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93
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Grundmann SM, Brandsch C, Rottstädt D, Kühne H, Stangl GI. The High Calcium, High Phosphorus Rescue Diet Is Not Suitable to Prevent Secondary Hyperparathyroidism in Vitamin D Receptor Deficient Mice. Front Physiol 2017; 8:212. [PMID: 28443031 PMCID: PMC5385385 DOI: 10.3389/fphys.2017.00212] [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] [Received: 12/08/2016] [Accepted: 03/23/2017] [Indexed: 01/22/2023] Open
Abstract
The vitamin D receptor (VDR) knockout (KO) mouse is a common model to unravel novel metabolic functions of vitamin D. It is recommended to feed these mice a high calcium (2%), high phosphorus (1.25%) diet, termed rescue diet (RD) to prevent hypocalcaemia and secondary hyperparathyroidism. First, we characterized the individual response of VDR KO mice to feeding a RD and found that the RD was not capable of normalizing the parathyroid hormone (PTH) concentrations in each VDR KO mouse. In a second study, we aimed to study whether RD with additional 1 and 2% calcium (in total 3 and 4% of the diet) is able to prevent secondary hyperparathyroidism in the VDR KO mice. Wild type (WT) mice and VDR KO mice that received a normal calcium and phosphorus diet (ND) served as controls. Data demonstrated that the RD was no more efficient than the ND in normalizing PTH levels. An excessive dietary calcium concentration of 4% was required to reduce serum PTH concentrations in the VDR KO mice to PTH levels measured in WT mice. This diet, however, resulted in higher concentrations of circulating intact fibroblast growth factor 23 (iFGF23). To conclude, the commonly used RD is not suitable to normalize the serum PTH in VDR KO mice. Extremely high dietary calcium concentrations are necessary to prevent secondary hyperthyroidism in these mice, with the consequence that iFGF23 concentrations are being raised. Considering that PTH and iFGF23 exert numerous VDR independent effects, data obtained from VDR KO mice cannot be attributed solely to vitamin D.
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Affiliation(s)
- Sarah M Grundmann
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-WittenbergHalle, Germany.,Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD), Halle-Jena-LeipzigHalle, Germany
| | - Corinna Brandsch
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-WittenbergHalle, Germany
| | - Daniela Rottstädt
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-WittenbergHalle, Germany
| | - Hagen Kühne
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-WittenbergHalle, Germany
| | - Gabriele I Stangl
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-WittenbergHalle, Germany.,Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD), Halle-Jena-LeipzigHalle, Germany
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94
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Abstract
Nuclear receptors are a family of transcription factors that can be activated by lipophilic ligands. They are fundamental regulators of development, reproduction, and energy metabolism. In bone, nuclear receptors enable bone cells, including osteoblasts, osteoclasts, and osteocytes, to sense their dynamic microenvironment and maintain normal bone development and remodeling. Our views of the molecular mechanisms in this process have advanced greatly in the past decade. Drugs targeting nuclear receptors are widely used in the clinic for treating patients with bone disorders such as osteoporosis by modulating bone formation and resorption rates. Deficiency in the natural ligands of certain nuclear receptors can cause bone loss; for example, estrogen loss in postmenopausal women leads to osteoporosis and increases bone fracture risk. In contrast, excessive ligands of other nuclear receptors, such as glucocorticoids, can also be detrimental to bone health. Nonetheless, the ligand-induced osteoprotective effects of many other nuclear receptors, e.g., vitamin D receptor, are still in debate and require further characterizations. This review summarizes previous studies on the roles of nuclear receptors in bone homeostasis and incorporates the most recent findings. The advancement of our understanding in this field will help researchers improve the applications of agonists, antagonists, and selective modulators of nuclear receptors for therapeutic purposes; in particular, determining optimal pharmacological drug doses, preventing side effects, and designing new drugs that are more potent and specific.
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95
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Fujii O, Tatsumi S, Ogata M, Arakaki T, Sakaguchi H, Nomura K, Miyagawa A, Ikuta K, Hanazaki A, Kaneko I, Segawa H, Miyamoto KI. Effect of Osteocyte-Ablation on Inorganic Phosphate Metabolism: Analysis of Bone-Kidney-Gut Axis. Front Endocrinol (Lausanne) 2017; 8:359. [PMID: 29312149 PMCID: PMC5742590 DOI: 10.3389/fendo.2017.00359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 12/11/2017] [Indexed: 01/24/2023] Open
Abstract
In response to kidney damage, osteocytes increase the production of several hormones critically involved in mineral metabolism. Recent studies suggest that osteocyte function is altered very early in the course of chronic kidney disease. In the present study, to clarify the role of osteocytes and the canalicular network in mineral homeostasis, we performed four experiments. In Experiment 1, we investigated renal and intestinal Pi handling in osteocyte-less (OCL) model mice [transgenic mice with the dentin matrix protein-1 promoter-driven diphtheria toxin (DT)-receptor that were injected with DT]. In Experiment 2, we administered granulocyte colony-stimulating factor to mice to disrupt the osteocyte canalicular network. In Experiment 3, we investigated the role of osteocytes in dietary Pi signaling. In Experiment 4, we analyzed gene expression level fluctuations in the intestine and liver by comparing mice fed a high Pi diet and OCL mice. Together, the findings of these experiments indicate that osteocyte ablation caused rapid renal Pi excretion (P < 0.01) before the plasma fibroblast growth factor 23 (FGF23) and parathyroid hormone (PTH) levels increased. At the same time, we observed a rapid suppression of renal Klotho (P < 0.01), type II sodium phosphate transporters Npt2a (P < 0.01) and Npt2c (P < 0.05), and an increase in intestinal Npt2b (P < 0.01) protein. In OCL mice, Pi excretion in feces was markedly reduced (P < 0.01). Together, these effects of osteocyte ablation are predicted to markedly increase intestinal Pi absorption (P < 0.01), thus suggesting that increased intestinal Pi absorption stimulates renal Pi excretion in OCL mice. In addition, the ablation of osteocytes and feeding of a high Pi diet affected FGF15/bile acid metabolism and controlled Npt2b expression. In conclusion, OCL mice exhibited increased renal Pi excretion due to enhanced intestinal Pi absorption. We discuss the role of FGF23-Klotho on renal and intestinal Pi metabolism in OCL mice.
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Affiliation(s)
- Osamu Fujii
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Sawako Tatsumi
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
- *Correspondence: Sawako Tatsumi, ; Ken-ichi Miyamoto,
| | - Mao Ogata
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Tomohiro Arakaki
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Haruna Sakaguchi
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Kengo Nomura
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Atsumi Miyagawa
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Kayo Ikuta
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Ai Hanazaki
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Ichiro Kaneko
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Hiroko Segawa
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
| | - Ken-ichi Miyamoto
- Department of Molecular Nutrition, Institution of Biomedical Science, Tokushima University Graduate School, Tokushima, Japan
- *Correspondence: Sawako Tatsumi, ; Ken-ichi Miyamoto,
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96
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Jin D, Zhang YG, Wu S, Lu R, Lin Z, Zheng Y, Chen H, Cs-Szabo G, Sun J. Vitamin D receptor is a novel transcriptional regulator for Axin1. J Steroid Biochem Mol Biol 2017; 165:430-437. [PMID: 27601169 PMCID: PMC5180453 DOI: 10.1016/j.jsbmb.2016.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 08/31/2016] [Accepted: 09/02/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Axin1 is a scaffold protein in the β-catenin destruction complex, which, if disrupted, contributes to pathogenesis of various human diseases, including colorectal carcinogenesis and inflammatory bowel diseases (IBD). We have previously demonstrated that Salmonella infection promotes the degradation and plasma sequestration of Axin1, leading to bacterial invasiveness and inflammatory responses. Vitamin D and the vitamin D receptor (VDR) appear to be important regulators of IBD and colon cancer. Although VDR and Axin1 are all involved in intestinal inflammation, it remains unclear whether these processes are related or function independently. In the current study, we hypothesize that VDR is an important regulator for the maintenance of physiological level of Axin1. METHODS Using the intestinal epithelial conditional VDR knockout mouse model (VDRΔIEC) and cultured cell lines, influences of VDR status on the expression of Axin1 was evaluated by Western blots and real-time PCR. Loss- and gain-of-function assays were used to investigate the regulation of VDR on Axin1 at the transcriptional and translational levels. Cells were treated with cycloheximide or actinomycin for molecular mechanistic studies. Candidate genomic VDR binding sites for Axin1 were tested by chromatin immunoprecipitation (ChIP) assay. Physical interactions among VDR, Axin1, and β-catenin were tested by immunoprecipitation. Cellular localization of Axin1 with different VDR status was determined by fractionation and immunohistochemistry. RESULTS We found that VDR deletion led to lower protein and mRNA levels of Axin1, whereas knockdown of Axin1 did not change the expression level of VDR protein. Immunoprecipitation data did not support physical interaction between VDR and Axin1. The VDR regulation of Axin1 was through a VDR genomic binding site for Axin1 gene on the regulatory region. Fractionation data showed that cytosolic Axin1 was significantly reduced due to VDR deletion, leaving the nuclear fraction unchanged. In ileum, Axin1 was distributed in the cytosol of apical epithelium and crypts. CONCLUSION VDR is important for the maintenance of physiological level of Axin1. The discovery of Axin1 as a VDR target gene provides novel and fundamental insights into the interactions between the VDR and β-catenin signaling pathways.
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Affiliation(s)
- Dapeng Jin
- Department of Biochemistry, Rush University, Chicago, IL, 60612, USA
| | - Yong-Guo Zhang
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Shaoping Wu
- Department of Biochemistry, Rush University, Chicago, IL, 60612, USA
| | - Rong Lu
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Zhijie Lin
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Yuanyuan Zheng
- Department of Biochemistry, Rush University, Chicago, IL, 60612, USA
| | - Honglei Chen
- Department of Biochemistry, Rush University, Chicago, IL, 60612, USA
| | | | - Jun Sun
- Department of Biochemistry, Rush University, Chicago, IL, 60612, USA; Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, 60612, USA.
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97
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Hudson JQ. Secondary Hyperparathyroidism in Chronic Kidney Disease: Focus on Clinical Consequences and Vitamin D Therapies. Ann Pharmacother 2016; 40:1584-93. [PMID: 16912241 DOI: 10.1345/aph.1g724] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Objective: To assess vitamin D–based treatment approaches for secondary hyperparathyroidism and its complications. Data Sources: A literature search was performed using MEDLINE (1990–February 28, 2006). Key words used were chronic kidney disease and vitamin D to identify relevant papers published in English. Study Selection and Data Extraction: From the database of articles generated, 48 papers were identified. Titles and abstracts were examined to identify those directly related to the objective. Discussion was expanded through the bibliographies of cited articles. Data Synthesis: The increasing prevalence of chronic kidney disease (CKD) in the US indicates an urgent need for treatment strategies to delay or prevent disease progression. Abnormalities in phosphorus and calcium homeostasis, vitamin D levels, and the subsequent development of secondary hyperparathyroidism (SHPT) are secondary complications of CKD associated with increased morbidity and mortality. Management options include dietary phosphorus restriction, phosphate binders and/or calcium supplementation, vitamin D supplementation, and calcimimetics. Vitamin D supplementation has received increased attention given the prevalence of vitamin D deficiency in patients with CKD and the beneficial effect of correcting this deficiency. Conclusions: Early identification and intervention appropriate to the stage of CKD are likely to improve patient outcomes. Improved knowledge of interactions between vitamin D and vitamin D receptors has led to the development of vitamin D analogs and calcimimetics, which offer benefits in the management of SHPT. Integrating available treatment options into practice to achieve optimal therapeutic goals of SHPT based on the stage of CKD is a significant challenge for pharmacists managing patients with CKD.
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Affiliation(s)
- Joanna Q Hudson
- Department of Clinical Pharmacy, The University of Tennessee, Memphis, TN 38163-0001, USA.
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98
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van Goor MKC, Hoenderop JGJ, van der Wijst J. TRP channels in calcium homeostasis: from hormonal control to structure-function relationship of TRPV5 and TRPV6. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:883-893. [PMID: 27913205 DOI: 10.1016/j.bbamcr.2016.11.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/23/2016] [Indexed: 12/16/2022]
Abstract
Maintaining plasma calcium levels within a narrow range is of vital importance for many physiological functions. Therefore, calcium transport processes in the intestine, bone and kidney are tightly regulated to fine-tune the rate of absorption, storage and excretion. The TRPV5 and TRPV6 calcium channels are viewed as the gatekeepers of epithelial calcium transport. Several calciotropic hormones control the channels at the level of transcription, membrane expression, and function. Recent technological advances have provided the first near-atomic resolution structural models of several TRPV channels, allowing insight into their architecture. While this field is still in its infancy, it has increased our understanding of molecular channel regulation and holds great promise for future structure-function studies of these ion channels. This review will summarize the mechanisms that control the systemic calcium balance, as well as extrapolate structural views to the molecular functioning of TRPV5/6 channels in epithelial calcium transport.
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Affiliation(s)
- Mark K C van Goor
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Joost G J Hoenderop
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands.
| | - Jenny van der Wijst
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands.
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99
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Lee SM, Pike JW. The vitamin D receptor functions as a transcription regulator in the absence of 1,25-dihydroxyvitamin D 3. J Steroid Biochem Mol Biol 2016; 164:265-270. [PMID: 26323657 PMCID: PMC4769962 DOI: 10.1016/j.jsbmb.2015.08.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/13/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
Abstract
The vitamin D receptor (VDR) is a critical mediator of the biological actions of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). As a nuclear receptor, ligand activation of the VDR leads to the protein's binding to specific sites on the genome that results in the modulation of target gene expression. The VDR is also known to play a role in the hair cycle, an action that appears to be 1,25(OH)2D3-independent. Indeed, in the absence of the VDR as in hereditary 1,25-dihydroxyvitamin D resistant rickets (HVDRR) both skin defects and alopecia emerge. Recently, we generated a mouse model of HVDRR without alopecia wherein a mutant human VDR lacking 1,25(OH)2D3-binding activity was expressed in the absence of endogenous mouse VDR. While 1,25(OH)2D3 failed to induce gene expression in these mice, resulting in an extensive skeletal phenotype, the receptor was capable of restoring normal hair cycling. We also noted a level of secondary hyperparathyroidism that was much higher than that seen in the VDR null mouse and was associated with an exaggerated bone phenotype as well. This suggested that the VDR might play a role in parathyroid hormone (PTH) regulation independent of 1,25(OH)2D3. To evaluate this hypothesis further, we contrasted PTH levels in the HVDRR mouse model with those seen in Cyp27b1 null mice where the VDR was present but the hormone was absent. The data revealed that PTH was indeed higher in Cyp27b1 null mice compared to VDR null mice. To evaluate the mechanism of action underlying such a hypothesis, we measured the expression levels of a number of VDR target genes in the duodena of wildtype mice and in transgenic mice expressing either normal or hormone-binding deficient mutant VDRs. We also compared expression levels of these genes between VDR null mice and Cyp27b1 null mice. In a subset of cases, the expression of VDR target genes was lower in mice containing the VDR as opposed to mice that did not. We suggest that the VDR may function as a selective suppressor/de-repressor of gene expression in the absence of 1,25(OH)2D3.
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Affiliation(s)
- Seong Min Lee
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States.
| | - J Wesley Pike
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, United States
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Kovacs CS. Maternal Mineral and Bone Metabolism During Pregnancy, Lactation, and Post-Weaning Recovery. Physiol Rev 2016; 96:449-547. [PMID: 26887676 DOI: 10.1152/physrev.00027.2015] [Citation(s) in RCA: 251] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
During pregnancy and lactation, female physiology adapts to meet the added nutritional demands of fetuses and neonates. An average full-term fetus contains ∼30 g calcium, 20 g phosphorus, and 0.8 g magnesium. About 80% of mineral is accreted during the third trimester; calcium transfers at 300-350 mg/day during the final 6 wk. The neonate requires 200 mg calcium daily from milk during the first 6 mo, and 120 mg calcium from milk during the second 6 mo (additional calcium comes from solid foods). Calcium transfers can be more than double and triple these values, respectively, in women who nurse twins and triplets. About 25% of dietary calcium is normally absorbed in healthy adults. Average maternal calcium intakes in American and Canadian women are insufficient to meet the fetal and neonatal calcium requirements if normal efficiency of intestinal calcium absorption is relied upon. However, several adaptations are invoked to meet the fetal and neonatal demands for mineral without requiring increased intakes by the mother. During pregnancy the efficiency of intestinal calcium absorption doubles, whereas during lactation the maternal skeleton is resorbed to provide calcium for milk. This review addresses our current knowledge regarding maternal adaptations in mineral and skeletal homeostasis that occur during pregnancy, lactation, and post-weaning recovery. Also considered are the impacts that these adaptations have on biochemical and hormonal parameters of mineral homeostasis, the consequences for long-term skeletal health, and the presentation and management of disorders of mineral and bone metabolism.
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Affiliation(s)
- Christopher S Kovacs
- Faculty of Medicine-Endocrinology, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
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