Filtered By:
Nutrition: Vitamins
This page shows you your search results in order of date. This is page number 17.
Order by Relevance | Date
Total 289 results found since Jan 2013.
Title: Vitamin D-induced ectodomain shedding of TNF receptor 1 as a nongenomic action: D3 vs D2 derivatives
In this study, we examined the potencies of other vitamin D3 and D2 analogs to stimulate the ectodomain shedding of TNFR1 in HASMCs. 25-Hydroxyvitamin D3 (25D3), a precursor of 1,25D3, and elocalcitol, an analog of 1,25D3, caused ectodomain shedding of TNFR1 within 30min, whereas 1,25-dihydroxyvitamin D2 (1,25D2) and paricalcitol, a derivative of 1,25D2, did not. Both 25D3 and elocalcitol rapidly induced extracellular Ca2+ influx and markedly increased intracellular Ca2+, while 1,25D2 and paricalcitol caused only small increases in intracellular Ca2+. 25D3- and elocalcitol-induced TNFR1 ectodomain sheddings were abolished ...
Source: The Journal of Steroid Biochemistry and Molecular Biology - September 16, 2015 Category: Biochemistry Source Type: research
Vitamin D Receptor-Mediated Upregulation of CYP3A4 and MDR1 by Quercetin in Caco-2 cells
Planta MedDOI: 10.1055/s-0035-1557898To examine whether quercetin interacts with vitamin D receptor, we investigated the effects of quercetin on vitamin D receptor activity in human intestinal Caco-2 cells. The effects of quercetin on the expression of the vitamin D receptor target genes, vitamin D3 24-hydroxylase, cytochrome P450 3A4, multidrug resistance protein 1, and transient receptor potential vanilloid type 6 were measured using quantitative polymerase chain reaction. The vitamin D receptor siRNA was used to assess the involvement of the vitamin D receptor. Vitamin D receptor activation using a vitamin D responsive ...
Source: Planta Medica - September 14, 2015 Category: Drugs & Pharmacology Authors: Chae, Yoon-JeeCho, Kwan HyungYoon, In-SooNoh, Chi-KyoungLee, Hyo-JongPark, YohanJi, EunheeSeo, Min-DukMaeng, Han-Joo Tags: Original Papers Source Type: research
Altered folate metabolism modifies cell proliferation and progesterone secretion in human placental choriocarcinoma JEG-3 cells.
Abstract
Folate is an essential B vitamin required for de novo purine and thymidylate synthesis, and for the remethylation of homocysteine to form methionine. Folate deficiency has been associated with placenta-related pregnancy complications, as have SNP in genes of the folate-dependent enzymes, methionine synthase (MTR) and methylenetetrahydrofolate dehydrogenase 1 (MTHFD1). We aimed to determine the effect of altered folate metabolism on placental cell proliferation, viability and invasive capacity and on progesterone and human chorionic gonadotropin (hCG) secretion. Human placental choriocarcinoma (JEG-3) cell...
Source: The British Journal of Nutrition - August 24, 2015 Category: Nutrition Authors: Moussa C, Ross N, Jolette P, MacFarlane AJ Tags: Br J Nutr Source Type: research
Up-regulation of steroid biosynthesis by retinoid signaling: Implications for aging
We reported that regulation of retinoid, especially atRA and 9-cis RA, responsive StAR transcription is largely mediated by an LXR-RXR/RAR heterodimeric motif in the mouse StAR promoter. Herein we demonstrate that retinoids are capable of enhancing StAR protein, P-StAR, and steroid production, in granulosa, adrenocortical, glial, and epidermal cells. Whereas transient expression of RARα and RXRα enhanced 9-cis RA-treated StAR gene transcription, silencing of RXRα with siRNA, decreased StAR and steroid levels. An oligonucleotide probe encompassing an LXR-RXR/RAR motif bound to adrenocortical and epidermal keratinocyte NE...
Source: Mechanisms of Ageing and Development - August 22, 2015 Category: Geriatrics Source Type: research
Abstract 1919: Warfarin-dependent gamma-carboxylation regulates androgen receptor activity
The anti-coagulant warfarin prevents the gamma-carboxylation (gla) of target proteins by interfering with the vitamin K cycle through its inhibition of the vitamin K epoxide reductase (VKOR). Most known gla proteins are found in the blood clotting cascade, but we demonstrate using immunoprecipitation and mass spectrometry that the androgen receptor (AR) can also be gamma-carboxylated. This modification occurs at amino acid 2E and can be prevented by warfarin treatment. This residue has been found to be mutated in partial androgen insensitivity syndrome patients. Warfarin, likely through its ability to control carboxylation...
Source: Cancer Research - August 2, 2015 Category: Cancer & Oncology Authors: Tew, B. Y., Hong, T., Pal, S. K., Kalkum, M., Jones, J. Tags: Prevention Research Source Type: research
Abstract 37: Role and regulation of CYP24A1 in endometrial cancer
The cytochrome P450 enzyme, 24-hydroxylase, encoded by CYP24A1 is critical for the catabolism of 1,25(OH)2D3 (calcitriol). The unbalanced high levels of CYP24A1 seem to be a determinant of calcitriol resistance in tumors. We have previously shown that progesterone enhances calcitriol antitumor activity by upregulating vitamin D receptor expression and promoting apoptosis in endometrial cancer cells. In the present study, we evaluated CYP24A1 protein expression in normal and endometrial tumor tissues, assessed the effect of progesterone and calcitriol on CYP24A1 and its spliced variant expression in endometrial cancer cell ...
Source: Cancer Research - August 2, 2015 Category: Cancer & Oncology Authors: Bokhari, A. A., Lee, L. R., Dewayne, R., Hamilton, C. A., Maxwell, G. L., Rodriguez, G. C., Syed, V. Tags: Molecular and Cellular Biology Source Type: research
1,25-Dihydroxyvitamin D3 and extracellular calcium promote mineral deposition via NPP1 activity in a mature osteoblast cell line MLO-A5
Publication date: 5 September 2015 Source:Molecular and Cellular Endocrinology, Volume 412 Author(s): Dongqing Yang , Andrew G. Turner , Asiri R. Wijenayaka , Paul H. Anderson , Howard A. Morris , Gerald J. Atkins While vitamin D supplementation is common, the anabolic mechanisms that improve bone status are poorly understood. Under standard mineralising conditions including media ionised calcium of 1.1 mM, 1,25-dihydroxyvitamin D3 (1,25D) enhanced differentiation and mineral deposition by the mature osteoblast/pre-osteocyte cell line, MLO-A5. This effect was markedly increased with a higher ionised calcium level (1.5...
Source: Molecular and Cellular Endocrinology - June 26, 2015 Category: Endocrinology Source Type: research
ATRA Stimulates DRA Expression Signal Transduction
In conclusion, ATRA may act as an antidiarrheal agent by increasing DRA expression via the RAR-β/HNF-1β-dependent pathway.
Source: Journal of Biological Chemistry - June 11, 2015 Category: Chemistry Authors: Priyamvada, S., Anbazhagan, A. N., Gujral, T., Borthakur, A., Saksena, S., Gill, R. K., Alrefai, W. A., Dudeja, P. K. Tags: Cell Biology Source Type: research
Fenretinide Inhibits Focal Adhesion Kinase
The membrane-associated protein, focal adhesion kinase (FAK), modulates cell–extracellular matrix interactions and also conveys prosurvival and proliferative signals. Notably, increased intraepithelial FAK levels accompany transformation of premalignant oral intraepithelial neoplasia (OIN) to oral squamous cell carcinoma (OSCC). OIN chemoprevention is a patient-centric, optimal strategy to prevent OSCC's comorbidities and mortality. The cancer chemopreventive and synthetic vitamin A derivative, fenretinide, has demonstrated protein-binding capacities, for example, mTOR- and retinol-binding protein interactions. These...
Source: Cancer Prevention Research - April 30, 2015 Category: Cancer & Oncology Authors: Han, B. B., Li, S., Tong, M., Holpuch, A. S., Spinney, R., Wang, D., Border, M. B., Liu, Z., Sarode, S., Pei, P., Schwendeman, S. P., Mallery, S. R. Tags: Research Articles Source Type: research
The terminal enzymes of cholesterol synthesis, DHCR24 and DHCR7, interact physically and functionally Research Articles
Cholesterol is essential to human health, and its levels are tightly regulated by a balance of synthesis, uptake, and efflux. Cholesterol synthesis requires the actions of more than twenty enzymes to reach the final product, through two alternate pathways. Here we describe a physical and functional interaction between the two terminal enzymes. 24-Dehydrocholesterol reductase (DHCR24) and 7-dehydrocholesterol reductase (DHCR7) coimmunoprecipitate, and when the DHCR24 gene is knocked down by siRNA, DHCR7 activity is also ablated. Conversely, overexpression of DHCR24 enhances DHCR7 activity, but only when a functional form of...
Source: The Journal of Lipid Research - March 30, 2015 Category: Lipidology Authors: Luu, W., Hart-Smith, G., Sharpe, L. J., Brown, A. J. Tags: Research Articles Source Type: research
The Role of Maternal Gestational Diabetes in Inducing Fetal Endothelial Dysfunction
This study examines the effect of maternal diabetes on fetal endothelial function and gene expression under physiological glucose conditions (5mM). Human umbilical vein endothelial cell (HUVEC) isolated from diabetic mothers (d.HUVEC) grew more slowly than HUVEC isolated from healthy mothers (c.HUVEC) and had delayed doubling time despite increased levels of total vascular endothelial growth factor (VEGF) expression and protein production as determined by real time PCR and ELISA respectively. Using western blot, the levels of antiproliferative VEGF165b isoform were increased in d.HUVEC relative to c.HUVEC. Successful VEGF1...
Source: Journal of Cellular Physiology - March 24, 2015 Category: Cytology Authors: Samar A Sultan, Wanting Liu, Yonghong Peng, W. Roberts, Donald Whitelaw, Anne M Graham Tags: Original Research Article Source Type: research
Identification of vitamin B1 metabolism as a tumor-specific radiosensitizing pathway using a high-throughput colony formation screen.
Authors: Tiwana GS, Prevo R, Buffa FM, Yu S, Ebner DV, Howarth A, Folkes LK, Budwal B, Chu KY, Durrant L, Muschel RJ, McKenna WG, Higgins GS
Abstract
Colony formation is the gold standard assay for determining reproductive cell death after radiation treatment, since effects on proliferation often do not reflect survival. We have developed a high-throughput radiosensitivity screening method based on clonogenicity and screened a siRNA library against kinases. Thiamine pyrophosphokinase-1 (TPK1), a key component of Vitamin B1/thiamine metabolism, was identified as a target for radiosensitization. TPK1 knockdown caused...
Source: Oncotarget - March 22, 2015 Category: Cancer & Oncology Tags: Oncotarget Source Type: research
Calcitriol prevents in vitro vascular smooth muscle cell mineralization by regulating Calcium-Sensing Receptor expression.
In conclusion, these findings suggest that nanomolar concentrations of 1,25(OH)2D3 induce a CaSR-dependent protection against VC. Both lower and higher concentrations are either ineffective or may even promote VC. Whether this also holds true in the clinical setting requires further study.
PMID: 25763635 [PubMed - as supplied by publisher]
Source: Endocrinology - March 12, 2015 Category: Endocrinology Authors: Mary A, Hénaut L, Boudot C, Six I, Brazier M, Massy ZA, Drüeke TB, Kamel S, Mentaverri R Tags: Endocrinology Source Type: research
Activation of AMP‐activated protein kinase by retinoic acid sensitizes hepatocellular carcinoma cells to apoptosis induced by sorafenib
In this study, we investigated the effects of combined treatment using sorafenib and retinoids including all‐trans retinoic acid (ATRA), NIK‐333, and Am80 on HCC cells. Cell viability assays in six HCC cell lines, HepG2, PLC/PRF/5, HuH6, HLE, HLF, and Hep3B, revealed that 5 and 10 μM ATRA, concentrations that do not exert cytotoxic effects, enhanced the cytotoxicity of sorafenib, being much more effective than NIK‐333 and Am80. We found that ATRA induced AMP‐activated protein kinase activation, which was followed by reduced intracellular ATP level. Gene expression analysis revealed that ATRA decreased the express...
Source: Cancer Science - March 9, 2015 Category: Cancer & Oncology Authors: Naoki Ishijima, Keita Kanki, Hiroki Shimizu, Goshi Shiota Tags: Original Article Source Type: research
Retinoic acid-induced IgG production in TLR-activated human primary B cells involves ULK1-mediated autophagy.
Abstract
In the present study we have established a vital role of autophagy in retinoic acid (RA)-induced differentiation of toll-like receptor (TLR)-stimulated human B cells into Ig-secreting cells. Thus, RA enhanced autophagy in TLR9- and CD180-stimulated peripheral blood B cells, as revealed by increased levels of the autophagosomal marker LC3B-II, enhanced colocalization between LC3B and the lysosomal marker Lyso-ID, by a larger percentage of cells with more than 5 characteristic LC3B puncta, and by the concomitant reduction in the level of SQSTM1/p62. Furthermore, RA induced expression of the autophagy-induci...
Source: Autophagy - March 6, 2015 Category: Cytology Authors: Eriksen AB, Torgersen ML, Holm KL, Abrahamsen G, Spurkland A, Moskaug JØ, Simonsen A, Blomhoff HK Tags: Autophagy Source Type: research
