Read by QxMD icon Read

1a,25-dihydroxyvitamin D

Geoffrey N Hendy, Lucie Canaff
The human calcium-sensing receptor gene (CASR) has 8 exons, and localizes to chromosome 3q. Exons 1A and 1B encode alternative 5'-untranslated regions (UTRs) that splice to exon 2 encoding the AUG initiation codon. Exons 2-7 encode the CaSR protein of 1078 amino acids. Promoter P1 has TATA and CCAAT boxes upstream of exon 1A, and promoter P2 has Sp1/3 motifs at the start site of exon 1B. Exon 1A transcripts from the P1 promoter are reduced in parathyroid tumors and colon carcinomas. Studies of colon carcinomas and neuroblastomas have emphasized the importance of epigenetic changes-promoter methylation of the GC-rich P2 promoter, histone acetylation-as well as involvement of microRNAs in bringing about CASR gene silencing and reduced CaSR expression...
2016: Frontiers in Physiology
Yingjuan Lv, Qingbin Yao, Wenjiang Ma, Hua Liu, Jian Ji, Xiaorong Li
BACKGROUND: Vitamin D deficiency and vitamin D receptor gene polymorphisms are known to be significantly associated with high myopia. Whether this genetic variant may impact primary open-angle glaucoma is largely unknown. This study investigated whether vitamin D receptor gene polymorphisms are altered in primary open-angle glaucoma subjects carrying the risk allele, and whether vitamin D deficiency is an important factor in the development of glaucoma. METHODS: Seventy-three POAG patients and 71 age-matched controls from the Han population were enrolled...
2016: BMC Ophthalmology
Matan Nachliely, Ehud Sharony, Narasimha Rao Bolla, Andrzej Kutner, Michael Danilenko
1α,25-dihydroxyvitamin D₃ (1,25D3) is a powerful differentiation inducer for acute myeloid leukemia (AML) cells. However, 1,25D3 doses required for differentiation of AML cells may cause lethal hypercalcemia in vivo. There is evidence that vitamin D₂ is less toxic than vitamin D₃ in animals. Here, we determined the differentiation effects of novel analogs of 1α,25-dihydroxyvitamin D₂ (1,25D2), PRI-1916 and PRI-1917, in which the extended side chains of their previously reported precursors (PRI-1906 and PRI-1907, respectively) underwent further 24Z (24-cis) modification...
2016: International Journal of Molecular Sciences
Bahar Özcabı, Feride Tahmiscioğlu Bucak, Sevinç Jaferova, Çiğdem Oruç, Amra Adrovic, Serdar Ceylaner, Oya Ercan, Olcay Evliyaoğlu
BACKGROUND: Vitamin D dependent rickets type 1A (VDDR-1A) (OMIM#264700) is a rare, autosomal-recessively inherited disorder due to inactivating mutations in CYP27B1. It is characterized by early onset of rickets with hypocalcemia. We aimed to describe clinical, laboratory findings in VDDR-1A and report a novel homozygote truncating mutation NM_000785.3 c.403C>T (p.Q135*) in CYP27B1 which as far as we know is the first described mutation in Uzbek population. CASE: The patient was admitted with tetany at the age of 12 months...
June 29, 2016: Journal of Clinical Research in Pediatric Endocrinology
Aleksandra Marchwicka, Małgorzata Cebrat, Agnieszka Łaszkiewicz, Łukasz Śnieżewski, Geoffrey Brown, Ewa Marcinkowska
Acute myeloid leukemia (AML) is the predominant acute leukemia among adults, characterized by an accumulation of malignant immature myeloid precursors. A very promising way to treat AML is differentiation therapy using either all-trans-retinoic acid (ATRA) or 1,25-dihydroxyvitamin D3 (1,25D), or the use of both these differentiation-inducing agents. However, the effect of combination treatment varies in different AML cell lines, and this is due to ATRA either down- or up-regulating transcription of vitamin D receptor (VDR) in the cells examined...
May 2016: Journal of Steroid Biochemistry and Molecular Biology
Niek F Dirks, Frans Martens, Dirk Vanderschueren, Jaak Billen, Steven Pauwels, Mariëtte T Ackermans, Erik Endert, Martin den Heijer, Marinus A Blankenstein, Annemieke C Heijboer
BACKGROUND: To assess a patient's vitamin D status the precursor metabolite 25-hydroxyvitamin D can be determined. However, measurement of 1,25-dihydroxyvitamin D is required when disorders of 1a-hydroxylation, extrarenal 1a-hydroxylation, or vitamin D receptor defects are suspected. METHODS: The aim of this study was to determine reference values for 1,25-dihydroxyvitamin D3 and D2 using a 2D ID-UPLC-MS/MS method. RESULTS: The LC-MS/MS method, able to measure picomolar concentrations of both 1,25-dihydroxyvitamin D3 and D2 in human serum, was extensively validated...
December 9, 2015: Journal of Steroid Biochemistry and Molecular Biology
Toshie Fujishima, Tsutomu Suenaga, Takato Nozaki
The hormonally active form of vitamin D3, 1α,25-dihydroxyvitamin D3 (1a), has a wide variety of biological activities and its major molecular target is considered to be the vitamin D receptor (VDR). The A-ring stereoisomers of 1a as well as its C2-modified analogues, which have different stereochemistry at the C1 and/or C3 hydroxy groups, are of interest since recent metabolic studies have shown that catabolism could occur through A-ring modification. In this review, a practical and versatile synthesis of the A-ring enyne precursors by the convergent method of Trost and coworkers, which is needed to construct all possible A-ring stereoisomers of 1,25-dihydroxyvitamin D3 (1a-d), and the C2-modified analogues (4a-d, 5a-d, 6a-d and 7a-d) is described...
2014: Current Topics in Medicinal Chemistry
María Jesús Larriba, José Manuel González-Sancho, Antonio Barbáchano, Núria Niell, Gemma Ferrer-Mayorga, Alberto Muñoz
The Wnt/b-catenin signaling pathway is abnormally activated in most colorectal cancers and in a proportion of other neoplasias. This activation initiates or contributes to carcinogenesis by regulating the expression of a large number of genes in tumor cells. The active vitamin D metabolite 1a,25-dihydroxyvitamin D3 (1,25(OH)2D3) inhibits Wnt/b-catenin signaling by several mechanisms at different points along the pathway. Additionally, paracrine actions of 1,25(OH)2D3 on stromal cells may also repress this pathway in neighbouring tumor cells...
2013: Cancers
Doris M Hummel, Irfete S Fetahu, Charlotte Gröschel, Teresa Manhardt, Enikő Kállay
Interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) are proinflammatory cytokines that play a critical role in inflammatory bowel disease, as well as in colorectal tumorigenesis. We hypothesize that these cytokines modulate the expression and thus activity of the vitamin D system in colonic epithelial cells. We treated the colon cancer cell line COGA-1A for 6, 12, and 24h with 1,25-dihydroxyvitamin D3 (1,25-D3), IL-6, TNFα, and with combinations of these compounds. Using quantitative RT-PCR, we analyzed mRNA expression of genes activating and catabolizing 1,25-D3 (1α-hydroxylase (CYP27B1), 24-hydroxylase (CYP24A1)), expression of several vitamin D target genes, as well as expression of cyclooxygenase 2 (COX-2) and 15-hydroxyprostaglandin dehydrogenase...
October 2014: Journal of Steroid Biochemistry and Molecular Biology
Miki Matsuo, Asami Hasegawa, Masashi Takano, Hiroshi Saito, Shinji Kakuda, Kenichiro Takagi, Eiji Ochiai, Kyohei Horie, Midori Takimoto-Kamimura, Kazuya Takenouchi, Daisuke Sawada, Atsushi Kittaka
X-ray cocrystallographic studies of the human vitamin D receptor (hVDR)-[2α-(3-hydroxypropyl)-1α,25-dihydroxyvitamin D3 (O1C3)] complex showed that the terminal hydroxy group of the 2α-functional group of O1C3 formed a hydrogen bond with Arg274 in the ligand binding domain (LBD) of hVDR to stabilize the complex; therefore, O1C3 showed 3-times greater binding affinity for VDR than the natural hormone. Here, the effects of a heteroaromatic ring on binding to hVDR instead of the terminal OH group of O1C3 and also on preliminary biological activities were studied...
October 2014: Journal of Steroid Biochemistry and Molecular Biology
Geoffrey N Hendy, Lucie Canaff, David E C Cole
The calcium-sensing receptor (CaSR) is a G protein-coupled receptor encoded by a single copy gene. The human CASR gene spans ~103-kb and has eight exons. Promoters P1 and P2 drive transcription of exons 1A and 1B, respectively, encoding alternative 5'-UTRs that splice to exon 2 encoding the common part of the 5'-UTR. Exons 2-7 encode the CaSR protein of 1078 amino acids. Functional elements responsive to 1,25-dihydroxyvitamin D, proinflammatory cytokines, and glial cells missing-2 are present in the CASR promoters...
June 2013: Best Practice & Research. Clinical Endocrinology & Metabolism
Shinsuke Kido, Ichiro Kaneko, Sawako Tatsumi, Hiroko Segawa, Ken-ichi Miyamoto
The type II sodium-dependent Pi (NaPi) cotransporters (NaPi-IIa, NaPi-IIb and NaPi-IIc) contribute to renal and intestinal Pi absorption. 1,25-Dihydroxyvitamin D [1,25(OH)2D3] is an important factor for NaPi-II transporters in the small intestine and kidney. In a previous study, low levels of 1,25(OH)2D3 appeared to suppress the expression of renal NaPi cotransporters. We identified a functional vitamin D receptor-responsive element in the human NaPi-IIa and NaPi-IIc genes in renal epithelial cells. In an analysis of vitamin D receptor (VDR)-null mice, we observed early onset of hypophosphatemia...
2013: Contributions to Nephrology
Sathish K R Padi, Qunshu Zhang, Youcef M Rustum, Carl Morrison, Bin Guo
BACKGROUND & AIMS: Vitamin D protects against colorectal cancer through unclear mechanisms. We investigated the effects of calcitriol (1α,25-dihydroxyvitamin D3; the active form of vitamin D) on levels of different microRNAs (miRNAs) in colorectal cancer cells from humans and xenograft tumors in mice. METHODS: Expression of miRNAs in colorectal cancer cell lines was examined using the Ambion mirVana miRNA Bioarray. The effects of calcitriol on expression of miR-627 and cell proliferation were determined by real-time polymerase chain reaction and WST-1 assay, respectively; growth of colorectal xenograft tumors was examined in nude mice...
August 2013: Gastroenterology
Y Morán-Auth, M Penna-Martinez, F Shoghi, E Ramos-Lopez, K Badenhoop
BACKGROUND: Vitamin D is a modulator of the immune system. Its insufficiency has been implicated in type 1 diabetes (T1D) and studies showed significant associations with polymorphisms of vitamin D genes. Aim of the study was to investigate whether gene expression in immune cells, vitamin D status and genetic variants are correlated in healthy controls (HC). METHODS: From 23 HC monocytes (Mo), T-helper cells (Th) and natural killer cells (NK) were isolated. In all immune cells gene expression of vitamin D receptor (VDR), 25-vitamin-D-hydroxylase (CYP2R1) and 25-hydroxyvitamin-D3-1a-hydroxylase (CYP27B1) were measured by Taqman assay...
July 2013: Journal of Steroid Biochemistry and Molecular Biology
Andreas G Moraitis, Martin Hewison, Michael Collins, Candido Anaya, Michael F Holick
OBJECTIVE: Granuloma-forming diseases such as sarcoidosis are associated with extrarenal synthesis of 1,25-dihydroxyvitamin D [1,25(OH)₂D]. We describe a case of extensive skin lesions associated with mineral oil injections in which we provide evidence for cutaneous granuloma synthesis of 1,25(OH)₂D in the pathogenesis of the patient's hypercalcemia. METHODS: Analysis of expression of the 25(OH)D-1a-hydroxylase (1-a OHase [CYP27b1]) was carried out by immunohistochemical analysis of involved skin...
March 2013: Endocrine Practice
Xiaolin Tang, Yaping Pan, Yanyan Zhao
OBJECTIVE: Vitamin D has been known to be closely associated with periodontitis while the exact mechanisms remain unclear. The present study aimed to discover the effects of 1a,25-dihydroxyvitamin D3 (1,25D) on the expressions of interleukin (IL)-6 and IL-8 in human periodontal ligament cells (hPDLCs) stimulated with Porphyromonas gingivalis (P. gingivalis) W83. DESIGN: Primary cultures of hPDLCs from ten donors were established and the cells of passage four were treated with 1,25D or P...
April 2013: Archives of Oral Biology
Xiangwen Chen-Deutsch, George P Studzinski
Recent clinical trials aimed at improved treatment of AML by administration of vitamin D derivatives showed unremarkable results, suggesting development of vitamin D resistance in patients' AML blasts. Since mechanisms of vitamin D resistance are not clear, we studied 40AF cells, a subline of HL60 cells that can proliferate in the presence of 1α,25-dihydroxyvitamin D₃ (1,25D). We found that mRNA and protein levels of HPK1, an upstream MAP4 kinase, are dramatically increased in 40AF cells, and HPK1 protein is further increased when the 1,25D resistance of 40AF cells is partially reversed by the addition of carnosic acid and p38MAPK inhibitor SB202190 (DCS cocktail)...
April 1, 2012: Cell Cycle
Timoklia Orfanidou, Konstantinos N Malizos, Sokratis Varitimidis, Aspasia Tsezou
Hypertrophy and impaired mineralization are two processes closely associated with osteoarthritis (OA). 1,25-dihydroxyvitamin D(3) (1a,25(OH)(2)D(3)) and inorganic phosphate (Pi) are two important factors that are implicated in calcium and phosphate homeostasis of bone metabolism and both can be regulated by the circulating phosphaturic factor fibroblast growth factor 23 (FGF23). The objective of this study was to investigate the role of 1a,25(OH)(2)D(3) and Pi and the molecular mechanism through which they contribute to hypertrophy and mineralization in human osteoarthritic chondrocytes...
March 2012: Experimental Biology and Medicine
Hidekazu Koike, Yasuyuki Morikawa, Yoshitaka Sekine, Hiroshi Matsui, Yasuhiro Shibata, Kazuhiro Suzuki
PURPOSE: Prostate cancer cell proliferation is inhibited by 1a,25-dihydroxyvitamin D(3). Survivin is a member of the inhibitors of apoptosis protein family. Several studies indicate that survivin down-regulation sensitizes human tumor cells of different histological origins to conventional chemotherapeutic drugs. We assessed the effect of survivin gene expression on the proliferation of prostate cancer cells in vitro and in vivo. We also examined the antitumor sensitization effect of survivin inhibition in 1a,25-dihydroxyvitamin D(3) treatment for prostate cancer cells...
April 2011: Journal of Urology
Guisheng Zhao, Robert U Simpson
We show that 1alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) and a synthetic non-genotropic vitamin D analog agonist, 1a,25(OH)2-lumisterol (JN), exhibit similar rapid effects on sarcomere shortening (contraction) of isolated adult cardiomyocyte. We also report that the vitamin D receptor (VDR) specifically interacts with caveolin-3 in the t-tubules and sarcolemma of isolated adult rat cardiac myocytes. Confocal immunofluorescence microscopy analysis showed co-localization of VDR and caveolin-3 in the t-tubules and sarcolemma of cardiomyocytes...
July 2010: Journal of Steroid Biochemistry and Molecular Biology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"