scholarly journals Extrahepatic 25-Hydroxylation of Vitamin D3 in an Engineered Osteoblast Precursor Cell Line Exploring the Influence on Cellular Proliferation and Matrix Maturation during Bone Development

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Shelley S. Mason ◽  
Sean S. Kohles ◽  
Shelley R. Winn ◽  
Randy D. Zelick
Keyword(s):  
Vitamin D ◽  
Cell Line ◽  
Cellular Proliferation ◽  
Bone Development ◽  
Precursor Cell ◽  
Dependent Manner ◽  
Dihydroxyvitamin D ◽  
Osteogenic Response ◽  
Osteoblast Precursors ◽  
Osteoblast Precursor Cell

Osteoblastic precursors experience distinct stages during differentiation and bone development, which include proliferation, extracellular matrix (ECM) maturation, and ECM mineralization. It is well known that vitamin D plays a large role in the regulation of bone mineralization and homeostasis via the endocrine system. The activation of vitamin D requires two sequential hydroxylation steps, first in the kidney and then in the liver, in order to carry out its role in calcium homeostasis. Recent research has demonstrated that human-derived mesenchymal stem cells (MSCs) and osteoblasts can metabolize the immediate vitamin D precursor 25-dihydroxyvitamin D3 (25OHD3) to the active steroid 1α,25-dihydroxyvitamin D3 (1,25OH2D3) and elicit an osteogenic response. However, reports of extrahepatic metabolism of vitamin D3, the parental vitamin D precursor, have been limited. In this study, we investigated whether osteoblast precursors have the capacity to convert vitamin D3 to 1,25OH2D3 and examined the potential of vitamin D3 to induce 1,25OH2D3 associated biological activities in osteoblast precursors. It was demonstrated that the engineered osteoblast precursor derived from human marrow (OPC1) is capable of metabolizing vitamin D3 to 1,25OH2D3 in a dose-dependent manner. It was also demonstrated that administration of vitamin D3 leads to the increase in alkaline phosphatase (ALP) activity associated with osteoblast ECM maturation and calcium deposits and a decrease in cellular proliferation in both osteoblast precursor cell lines OPC1 and MC3T3-E1. These findings provide a two-dimensional culture foundation for future three-dimensional engineered tissue studies using the OPC1 cell line.

Vitamin D-regulated calcium transport in Caco-2 cells: unique in vitro model

1991 ◽  
Vol 260 (2) ◽  
pp. G207-G212 ◽  
Author(s):  
A. R. Giuliano ◽  
R. J. Wood
Keyword(s):  
Vitamin D ◽  
Cell Line ◽  
Calcium Transport ◽  
In Vitro Model ◽  
Colon Adenocarcinoma ◽  
Intestinal Cell ◽  
Maximal Velocity ◽  
Dependent Manner ◽  
Vitro Model

The human colon adenocarcinoma cell line Caco-2 is the only intestinal cell line to differentiate spontaneously in culture exhibiting structural and biochemical characteristics of mature enterocytes and to possess a vitamin D receptor in the fully differentiated state. Transepithelial calcium transport was characterized in differentiated Caco-2 cells grown on permeable filters supports to assess the potential utility of this cell line as an in vitro model to study 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]-induced calcium transport. Calcium transport was increased in a dose-dependent manner by 1,25(OH)2D3. Total calcium transport at different calcium concentrations could be fitted to a modified Michaelis-Menten equation containing a linear transport component. The maximum rate of saturable calcium transport was increased by 4.3-fold (P less than 0.005) in cells treated with 10(-8) M 1,25(OH)2D3. This treatment also increased the apparent buffer calcium concentration that results in half-maximal velocity from 0.4 to 1.3 mM but had no significant effect on nonsaturable calcium transport. Caco-2 cells grown on permeable filter supports provide a unique in vitro human cell culture model to study the mechanism of vitamin D-regulated transepithelial intestinal calcium transport.

Effect of Estradiol on miR-21& miR-155 Expression in promyelocytic leukemia-derived cell line NB4

2020 ◽  
Author(s):  
Robab Naghibzadeh ◽  
Narges Obeidi ◽  
Alireza Farsinejd ◽  
Gholamreza Khamisipour ◽  
Masoud TohidFar
Keyword(s):  
Effective Dose ◽  
Cell Line ◽  
Myeloid Leukemia ◽  
Cellular Proliferation ◽  
Promyelocytic Leukemia ◽  
Dependent Manner ◽  
Trypan Blue Exclusion ◽  
Nb4 Cells ◽  
Dose Dependent ◽  
Mtt Assays

Background: Due to the estrogen participation in modulating the proliferation and commitment of stem cells and the effects of miR-21 and miR-155 expression on reduced proliferation and colony formation of acute myeloid leukemia (AML), the aim of the present study was to evaluate the effect of estradiol on expression of miR-21 and miR-155 in the NB4 cell line, as an acute promyelocytic leukemia (APL). Materials and Methods: In the present experiment, NB4 cells were treated with different quantities of estradiol (5, 25, 50, 75, 100, 150, 200, 250 μg/ml) and vehicle control for 24 and 48 hours. Viability, apoptosis, and cellular proliferation were estimated by trypan blue exclusion, flow cytometry, and MTT assays, respectively. The level of miR-155 and miR-21 expression was studied using absolute quantitative real-time PCR. Results: Results showed that estradiol in the effective dose (200 μg/ml) led to decreased cellular viability (in a dose dependent manner, P = 0.004) and apoptosis of NB4 cells. In addition, the expressions of miR-155 and miR-21 were significantly and dose-dependently decreased (p<0.05). Conclusion: Estradiol at the effective dose caused apoptosis in NB4 cell line. This substance can be used as a drug for the treatment of APL. However, further assessments are needed to support the effectiveness of estradiol in the treatment of APL.

Vitamin D metabolites regulate osteocalcin synthesis and proliferation of human bone cells in vitro

1985 ◽  
Vol 105 (3) ◽  
pp. 391-396 ◽  
Author(s):  
H. Skjødt ◽  
J. A. Gallagher ◽  
J. N. Beresford ◽  
M. Couch ◽  
J. W. Poser ◽  
...  
Keyword(s):  
Vitamin D ◽  
Cell Proliferation ◽  
Bone Cells ◽  
Rank Order ◽  
Human Bone ◽  
Dependent Manner ◽  
Vitamin D Metabolites ◽  
Hydroxyvitamin D ◽  
Dihydroxyvitamin D

ABSTRACT The effects of six natural vitamin D metabolites of potential biological and therapeutic interest, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3), 25-hydroxyvitamin D3 (25-OH-D3), 24R,25-dihydroxyvitamin D3 (24R,25-(OH)2D3), 1,24R,25-trihydroxyvitamin D3 (1,24R,25-(OH)3D3), 25S,26-dihydroxyvitamin D3 (25S,26-(OH)2D3) and 1,25S,26-trihydroxyvitamin D3 (1,25S,26-(OH)3D3) on cell replication and expression of the osteoblastic phenotype in terms of osteocalcin production were examined in cultured human bone cells. At a dose of 5 × 10−12 mol/l, 1,25-(OH)2D3 stimulated cell proliferation, whereas at higher doses (5 × 10−9−5 × 10 −6 mol/l) cell growth was inhibited in a dose-dependent manner. The same pattern of effects was seen for the other metabolites in a rank order of potency: 1,25-(OH)2D3> 1,25S,26-(OH)3D3 = 1,24R,25-(OH)3D3>25S,26-(OH)2D3 = 24R,25-(OH)2D3 = 25-OH-D3. Synthesis of osteocalcin was induced by 1,25-(OH)2D3 in doses similar to those required to inhibit cell proliferation. Biphasic responses were observed for some of the metabolites in terms of osteocalcin synthesis, inhibitory effects becoming apparent at 5 × 10−6 mol/l. The cells did not secrete osteocalcin spontaneously. These results indicate that vitamin D metabolites may regulate growth and expression of differentiated functions of normal human osteoblasts. J. Endocr. (1985) 105, 391–396

scholarly journals 1,25-Dihydroxyvitamin D3 upregulates leptin expression in mouse adipose tissue

2012 ◽  
Vol 216 (2) ◽  
pp. 265-271 ◽  
Author(s):  
Juan Kong ◽  
Yunzi Chen ◽  
Guojun Zhu ◽  
Qun Zhao ◽  
Yan Chun Li
Keyword(s):  
Vitamin D ◽  
Adipose Tissue ◽  
Energy Homeostasis ◽  
Ex Vivo ◽  
Critical Role ◽  
Dependent Manner ◽  
Adipose Tissues ◽  
Dihydroxyvitamin D ◽  
1,25 Dihydroxyvitamin D ◽  
Leptin Expression

Leptin is an adipose tissue-derived hormone that plays a critical role in energy homeostasis. Vitamin D has been shown to regulate energy metabolism, but the relationship between vitamin D and leptin is unclear. Leptin expression and secretion was reduced in vitamin D receptor (VDR)-null mice and increased in transgenic (Tg) mice overexpressing the VDR in adipocytes; however, as leptin is mainly determined by fat mass, it is unclear whether the vitamin D hormone directly regulates leptin expression. To address this question, we determined the effect of vitamin D on leptin expressionin vivoandex vivo. One-week treatment of WT mice with the vitamin D analog RO-27-5646 led to a significant increase in adipose leptin mRNA transcript and serum leptin levels. Moreover, in adipose tissue cultures, 1,25-dihydroxyvitamin D markedly stimulated mRNA expression and secretion of leptin, but not resistin, in adipose tissues obtained from WT mice, but not from VDR-null mice, and leptin upregulation induced by 1,25-dihydroxyvitamin D was more robust in adipose tissues obtained from VDR Tg mice compared with WT mice. These data demonstrate that 1,25-dihydroxyvitamin D stimulates adipose leptin production in a VDR-dependent manner, suggesting that vitamin D may affect energy homeostasis through direct regulation of leptin expression.

scholarly journals Type 2 Iodothyronine Selenodeiodinase Is Expressed throughout the Mouse Skeleton and in the MC3T3-E1 Mouse Osteoblastic Cell Line during Differentiation

Endocrinology ◽  
2005 ◽  
Vol 146 (1) ◽  
pp. 195-200 ◽  
Author(s):  
Cecilia H. A. Gouveia ◽  
Marcelo A. Christoffolete ◽  
Clarissa R. Zaitune ◽  
José Miguel Dora ◽  
John W. Harney ◽  
...  
Keyword(s):  
Thyroid Hormone ◽  
Cell Line ◽  
Bone Cells ◽  
Bone Development ◽  
Cell Types ◽  
Osteoblastic Cell ◽  
Dependent Manner ◽  
Osteoblastic Cell Line ◽  
Serum T3

Thyroid hormone affects multiple aspects of bone metabolism, but little is known about thyroid hormone deiodination in bone cells except that cultures of skeletal cells and bone organ express types 1 and 2 iodothyronine deiodinases (D1 and D2) mRNAs. In the present study, outer ring deiodination (ORD) activity was detected in bone extracts of multiple sites of the mouse skeleton, bone marrow, and the MC3T3-E1 osteoblastic cell line. In all tissues, ORD was detected using 125I-rT3 or 125I-T4 as substrates and was found to be 6-n-propylthiouracil insensitive, display a Michaelis constant (T4) of approximately 1 nm, increase about 3-fold in hypo- and virtually disappear in thyrotoxicosis. Extracts of calvaria had the lowest ORD activity, whereas tibial and femoral extracts had roughly three times as much. The absence of ORD activity in bone extracts from mice with targeted disruption of the Dio2 gene confirms the principal role of D2 in this tissue. In the MC3T3-E1 osteoblasts, D2 activity increased in a time-dependent manner after plating, and with the content of selenium in the media, reaching a maximum 5–7 d later as cells attained more than 90% confluence. In these cells D2 half-life is about 30–40 min, which is further accelerated by exposure to substrate and stabilized by the proteasome inhibitor, MG132. Treatment with vitamin D [1,25(OH)2VD]-induced D2 activity by 2- to 3-fold as early as 24 h, regardless of the level of cell confluence, but estradiol, PTH, forskolin, leptin, TNFα, TGFβ, and dexamethasone did not affect D2. Given the role of D2 in other cell types and processes, it is likely that bone ORD not only plays a role in bone development and adult bone T3 homeostasis but also contributes to extrathyroidal T3 production and maintenance of serum T3.

scholarly journals Uncarboxylated Osteocalcin Stimulates 25-Hydroxy Vitamin D Production in Leydig Cell Line Through a GPRC6a-Dependent Pathway

Endocrinology ◽  
2014 ◽  
Vol 155 (11) ◽  
pp. 4266-4274 ◽  
Author(s):  
Luca De Toni ◽  
Vincenzo De Filippis ◽  
Simone Tescari ◽  
Marco Ferigo ◽  
Alberto Ferlin ◽  
...  
Keyword(s):  
Vitamin D ◽  
Cell Line ◽  
Chorionic Gonadotropin ◽  
Cross Talk ◽  
Leydig Cell ◽  
Human Chorionic Gonadotropin ◽  
Leydig Cells ◽  
Second Messengers ◽  
Dependent Manner ◽  
Key Enzyme

Abstract Recent studies disclosed a cross talk between testis and bone. By the action of LH, Leydig cells are able to modulate bone metabolism through testosterone and insulin-like factor 3. Moreover, LH modulates the Leydig expression of CYP2R1, the key enzyme involved in vitamin D (Vit D) 25-hydroxylation. However, pathways regulating CYP2R1 expression have been poorly investigated. The cross talk from the bone to the testis of the vitamin D 25-hydroxylase CYP2R1 involves osteocalcin (OC), which is produced by the osteoblasts and stimulates the production of testosterone by the Leydig cells through its putative receptor GPRC6A, a cation-sensing G-protein-coupled receptor. The aim of this study was to investigate the possible action of OC on CYP2R1 expression and 25-hydroxy Vit D (25-OH Vit D) production in a mouse Leydig cell line (MA-10). After confirmation of the expression of GPRC6A by MA-10, we found that stimulation with either human chorionic gonadotropin or uncarboxylated-OC (ucOC) increases CYP2R1 protein expression in a dose-dependent manner and, in turn, increases the release of 25-OH Vit D in culture medium. This effect was abolished by receptor blockade with, respectively, anti-LH receptor and anti-GPRC6A antibodies. Moreover, both agonists converged to phosphorylation of Erk1/2 by a likely differential action on second messengers. Human chorionic gonadotropin induced slow “tonic” increase of intercellular calcium and accumulation of cAMP, whereas ucOC mainly induced phasic increase of cell calcium. Supporting these findings, we found that serum ucOC positively correlated with 25-OH Vit D levels in 40 overweight male patients and 21 controls. Altogether, our results suggest that OC contributes with LH to 25-OH Vit D production by Leydig cells.

An in vitro osteoblast culture model using estrogen responsive Ks483 mouse osteoblast precursor cell line

Bone ◽  
2010 ◽  
Vol 47 ◽  
pp. S120
Author(s):  
K.M. Fagerlund ◽  
J.P. Rissanen ◽  
T. Suutari ◽  
A. Chan ◽  
J.M. Halleen
Keyword(s):  
Cell Line ◽  
Precursor Cell ◽  
Osteoblast Culture ◽  
Precursor Cell Line ◽  
Culture Model ◽  
Mouse Osteoblast ◽  
Osteoblast Precursor Cell
Sign in / Sign up

Export Citation Format

Share Document