(1,25-dihydroxycholecalciferol) articles in PubMed
- Osteomalacia induced by long-term low-dose adefovir dipivoxil: Clinical characteristics and genetic predictors. [Journal Article]
- Bone 2016 Sep 21BONE
- CONCLUSIONS: ADV can be nephrotoxic at a conventional dosage. The G/A genotype at c.2934 of the ABCC2 gene may be a predictor of patients at greater risk for developing ADV-associated tubulopathy. Larger case-control studies are needed to further verify this finding.
- Hypovitaminosis D and adipose tissue - cause and effect relationships in obesity. [Journal Article]
- Ann Agric Environ Med 2016 Jul 15; 23(3):403-9AA
- In recent years, attention has been focused on pleiotropic directions of effects exerted by vitamin D. Epidemiological data indicate that deficiency of vitamin D in various population groups represen...
In recent years, attention has been focused on pleiotropic directions of effects exerted by vitamin D. Epidemiological data indicate that deficiency of vitamin D in various population groups represents an increasingly widespread phenomenon, while a decreased serum concentration of calcitriol correlates with manifestation of civilization-linked diseases, including visceral obesity. This study aims at a review and synthesis of data linked to relationships between lowered vitamin D concentrations in blood and manifestation of obesity, and potential mechanisms which affect the concentration of the vitamin in conditions of an excessive accumulation of adipose tissue. Several variables are distinguished which can affect the status of vitamin D in obesity, but the key role in this respect is ascribed to the metabolic activity of visceral adipose tissue. Among others, the activity favours sequestration and modulation of calcitriol turnover. On the other hand, the effects of vitamin D on the process of adipogenesis and its involvement in remodelling of adipose tissue are pointed out. Also, several factors of an environmental nature (e.g. time of year/day, dietetic supply of vitamin D), genetic nature (e.g. genetic polymorphisms) and other conditioning (e.g. coexisting diseases, age, content of melanin in skin) cannot be bypassed as they may affect the concentration of vitamin D. Nevertheless, it still remains unresolved to what extent hypovitaminosis D represents the cause and to which it is the effect of obesity.
- Calcitriol reduces hepatic triglyceride accumulation and glucose output through Ca2+/CaMKKβ/AMPK activation under insulin-resistant conditions in type 2 diabetes mellitus. [Journal Article]
- Curr Mol Med 2016 Sep 20CM
- CONCLUSIONS: Our data indicate that calcitriol, at above-physiological serum concentrations, reduces hepatic triglyceride accumulation and glucose output, at least in part through activation of Ca2+/CaMKKβ/AMPK under insulin-resistant condition.
- Structural analysis and biological activities of BXL0124, a gemini analog of vitamin D. [Review]
- J Steroid Biochem Mol Biol 2016 Sep 17JS
- Gemini analogs of calcitriol, characterized by the extension of the C21-methyl group of calcitriol with a second chain, act as agonists of the vitamin D receptor (VDR). This second side chain of gemi...
Gemini analogs of calcitriol, characterized by the extension of the C21-methyl group of calcitriol with a second chain, act as agonists of the vitamin D receptor (VDR). This second side chain of gemini is accommodated in a new cavity inside the VDR created by the structural rearrangement of the protein core. The resulting conformational change preserves the active state of the receptor and bestows gemini compounds with biological activities that exceed those of calcitriol. Of particular interest are gemini's anti-cancer properties, and in this study we demonstrate anti-proliferative and tumor-reducing abilities of BXL0124 and BXL0097, differing only by the presence or absence, respectively, of the methylene group on the A ring. BXL0124 acts as a more potent VDR agonist than its 19-nor counterpart by activating VDR-mediated transcription at lower concentrations. In a similar manner, BXL0124 is more active than BXL0097 in growth inhibition of breast cancer cells and reduction of tumor volume. Structural comparisons of BXL0097 and BXL0124, as their VDR complexes, explain the elevated activity of the latter.
- Chronic moderate ethanol intake differentially regulates vitamin D hydroxylases gene expression in kidneys and xenografted breast cancer cells in female mice. [Journal Article]
- J Steroid Biochem Mol Biol 2016 Sep 14JS
- Factors affecting vitamin D metabolism may preclude anti-carcinogenic effects of its active metabolite calcitriol. Chronic ethanol consumption is an etiological factor for breast cancer that affects ...
Factors affecting vitamin D metabolism may preclude anti-carcinogenic effects of its active metabolite calcitriol. Chronic ethanol consumption is an etiological factor for breast cancer that affects vitamin D metabolism; however, the mechanisms underlying this causal association have not been fully clarified. Using a murine model, we examined the effects of chronic moderate ethanol intake on tumoral and renal CYP27B1 and CYP24A1 gene expression, the enzymes involved in calcitriol synthesis and inactivation, respectively. Ethanol (5% w/v) was administered to 25-hydroxyvitamin D3-treated or control mice during one month. Afterwards, human breast cancer cells were xenografted and treatments continued another month. Ethanol intake decreased renal Cyp27b1 while increased tumoral CYP24A1 gene expression.Treatment with 25-hydroxyvitamin D3 significantly stimulated CYP27B1 in tumors of non-alcohol-drinking mice, while increased both renal and tumoral CYP24A1. Coadministration of ethanol and 25-hydroxyvitamin D3 reduced in 60% renal 25-hydroxyvitamin D3-dependent Cyp24a1 upregulation (P<0.05). We found 5 folds higher basal Cyp27b1 than Cyp24a1 gene expression in kidneys, whereas this relation was inverted in tumors, showing 5 folds more CYP24A1 than CYP27B1. Tumor expression of the calcitriol target cathelicidin increased only in 25-hydroxyvitamin D3-treated non-ethanol drinking animals (P<0.05). Mean final body weight was higher in 25-hydroxyvitamin D3 treated groups (P<0.001). Overall, these results suggest that moderate ethanol intake decreases renal and tumoral 25-hydroxyvitamin D3 bioconversion into calcitriol, while favors degradation of both vitamin D metabolites in breast cancer cells. The latter may partially explain why alcohol consumption is associated with vitamin D deficiency and increased breast cancer risk and progression.
- Regression of Non-Alcoholic Fatty Liver by Vitamin D Supplement: A Double-Blind Randomized Controlled Clinical Trial. [Journal Article]
- Arch Iran Med 2016; 19(9):631-8AI
- CONCLUSIONS: Calcitriol supplementation combined with weight loss diet showed no significant effects on anthropometric measures in NAFLD patients. However, it may have positive effects on lipid profile, liver enzyme tests and insulin sensitivity during a weight-loss program.
- A new approach to 19-nor-A-ring phosphine oxide for the convergent synthesis of 19-nor-calcitriol. [Review]
- J Steroid Biochem Mol Biol 2016 Aug 31JS
- A new approach to 19-nor-A-ring phosphine oxide 5 together with a convergent synthesis of the vitamin D3 analogue 1α,25-dihydroxy-19-norvitamin D3 (3) have been developed. The 19-nor-A-ring is constr...
A new approach to 19-nor-A-ring phosphine oxide 5 together with a convergent synthesis of the vitamin D3 analogue 1α,25-dihydroxy-19-norvitamin D3 (3) have been developed. The 19-nor-A-ring is constructed from (S)-carvone. The triene system is assembled by a Wittig-Horner coupling.
- Body weight and 25-hidroxyvitamin D follicular levels: a prospective study of women submitted to in vitro fertilization. [Journal Article]
- JBRA Assist Reprod 2016; 20(3):127-31JA
- CONCLUSIONS: The body weight of the individuals with FF 25(OH)D3 deficiency measured in single follicles was significantly higher regardless of the etiology of infertility. Further epidemiologic and molecular studies are required to verify whether the amount of follicular 25(OH)D3 affects the outcome of IVF procedures.
- Chitinase 3-like 1 expression by human (MG63) osteoblasts in response to lysophosphatidic acid and 1,25-dihydroxyvitamin D3. [Journal Article]
- Biochimie 2016 Aug 27B
- Chitinase 3-like 1, otherwise known as YKL-40, is a secreted glycoprotein purported to have a role in extracellular matrix metabolism. The first mammalian cell type found to express YKL-40 was the hu...
Chitinase 3-like 1, otherwise known as YKL-40, is a secreted glycoprotein purported to have a role in extracellular matrix metabolism. The first mammalian cell type found to express YKL-40 was the human osteosarcoma-derived osteoblast, MG63. In that first study the active vitamin D3 metabolite, 1,25-dihydroxycholecalciferol (1,25D), stimulated YKL-40 expression, thereby indicating that a vital factor for skeletal health promoted YKL-40 synthesis by bone forming cells. However, when these MG63 cells were exposed to 1,25D they were also exposed to serum, a rich source of the pleiotropic lipid mediator, lysophosphatidic acid (LPA). Given that 1,25D is now known to co-operate with selected growth factors, including LPA, to influence human osteoblast differentiation we hypothesised that 1,25D and LPA may work together to stimulate osteoblast YKL-40 expression. Herein we report that 1,25D and LPA synergistically promote YKL-40 expression by MG63 cells. Inhibitors targeting AP1, MEK, Sp1 and STAT3 blunted the expression of both alkaline phosphatase and YKL-40 by MG63 cells in response to co-stimulation with 1,25D and LPA. Other ligands of the vitamin D receptor also co-operated with LPA in driving YKL-40 mobilisation. Collectively our findings highlight another important role of 1,25D and LPA in the regulation of human osteoblast function.
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- [Not Available]. [Journal Article]
- Nutr Hosp 2016; 33 Suppl 4:341NH
- El calcio (Ca) es el elemento mineral más abundante en nuestro organismo, ya que forma parte importante del esqueleto y los dientes. Supone alrededor del 2% del peso corporal. Las funciones del calci...
El calcio (Ca) es el elemento mineral más abundante en nuestro organismo, ya que forma parte importante del esqueleto y los dientes. Supone alrededor del 2% del peso corporal. Las funciones del calcio son: a) funciones esqueléticas y b) funciones reguladoras. El hueso está formado por una matriz proteica que se mineraliza de forma mayoritaria con calcio (el más abundante), fosfato y magnesio; para ello es imprescindible un correcto aporte dietético de Ca, fósforo y vitamina D. El Ca iónico (Ca2+) es un componente celular imprescindible para mantener y/o realizar las diferentes funciones especializadas de prácticamente todas las células del organismo. Debido a sus importantes funciones, el Ca2+ debe estar estrechamente regulado, manteniéndose sus concentraciones plasmáticas dentro de unos rangos estrechos. Para ello existe una respuesta precisa frente a la hipocalcemia o la hipercalcemia, en la que intervienen la parathormona, el calcitriol, la calcitonina y la vitamina K. Las ingestas de Ca en la población española son bajas en un porcentaje significativo de la población, especialmente en adultos mayores, sobre todo en las mujeres. La principal fuente de Ca en la dieta son la leche y todos sus derivados. Las verduras de hoja verde, frutas y legumbres pueden tener importancia como fuentes de Ca en un patrón alimentario mediterráneo. La biodisponibilidad del Ca de la dieta depende de factores fisiológicos y dietéticos. Los fisiológicos incluyen la edad, situación fisiológica (gestación y lactación), el estatus de Ca y vitamina D y la enfermedad. Diversos estudios relacionan la ingesta de Ca en la dieta y distintas enfermedades, como osteoporosis, cáncer, enfermedades cardiovasculares y obesidad.