Mise au pointActualité sur les effets de la vitamine D et l’évaluation du statut vitaminique DUpdate on vitamin D and evaluation of vitamin D status
Section snippets
Effets de la vitamine D
La 1,25(OH)2D agit via un récepteur cytosolique, le VDR, présent dans de nombreux tissus [1]. La 1,25(OH)2D peut exercer des effets endocrines (la 1,25(OH)2D produite par le rein est transportée dans le sang jusqu’à ses tissus cibles), ou des effets qu’on peut qualifier d’autocrines (de nombreux tissus expriment la 1-alpha hydroxylase ainsi que le VDR. La 25OHD pénètre dans ces tissus et y est hydroxylée en 1,25(OH)2D qui ne « ressort » pas de la cellule et y agit localement, l’excès étant
Évaluation du statut vitaminique D
Même si la 1,25(OH)2D est unanimement reconnue comme le métabolite actif de la vitamine D, plusieurs études suggèrent d’importantes fonctions physiologiques pour la 25OHD. D’une part, elle est le substrat pour la formation de 1,25(OH)2D et d’autre part, elle semble avoir une activité directe sur l’absorption intestinale du calcium, 200 à 1000 fois plus faible (suivant les études) que celle de la 1,25(OH)2D, mais avec des concentrations circulantes 500 à 1000 fois plus élevées [56]. De plus, les
Correction d’une insuffisance en vitamine D et maintien d’un statut vitaminique D optimal
Il s’agit de deux actions différentes qui souvent nécessiteront d’utiliser des doses différentes. Une question importante est de savoir si on doit doser la 25OHD avant de donner une supplémentation en vitamine D. Plus précisément, connaît-on la dose de vitamine D qui permettrait de monter la concentration de 25OHD de 95 % de la population au-dessus de 30 ng/mL (même chez ceux qui ont une concentration de 25OHD initiale inférieure à 5 ng/mL) sans que personne ou presque n’ait une concentration
Conclusion
Les connaissances sur la vitamine D ont beaucoup progressé ces dernières années et de nombreuses études sont en cours comme en témoigne le nombre très important de publications sur le sujet. La vitamine D ne peut plus être considérée comme étant uniquement nécessaire à la prévention des rachitismes/ostéomalacies. Son rôle dans la prévention des fractures ostéoporotiques périphériques du sujet âgé est maintenant bien démontré (en association avec du calcium) et de très nombreuses données
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Références (96)
- et al.
Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol
Am J Clin Nutr.
(2003) - et al.
An endocytic pathway essential for renal uptake and activation of the steroid 25-(OH) vitamin D3
Cell
(1999) - et al.
Osteomalacia due to vitamin D depletion: a neglected consequence of intestinal malabsorption
Am J Med
(2000) - et al.
Use of calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis
Lancet
(2007) - et al.
Low vitamin D status: a contributing factor in the pathogenesis of congestive heart failure?
J Am Coll Cardiol
(2003) - et al.
Normal plasma 1,25(OH)2 vitamin D in nutritional osteomalacia
Lancet
(1979) - et al.
Serum 25 hydroxy vitamin D and colon cancer: eight year prospective study
Lancet
(1989) - et al.
Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial
Am J Clin Nutr
(2007) - et al.
Vitamin D deficiency enhances the growth of MC-26 colon cancer xenografts in Balb/c mice
J Nutr
(2005) - et al.
1,25-dihydroxyvitamin D3 induces morphological and biochemical markers of apoptosis in MCF-7 breast cancer cells
J Steroid Biochem Mol Biol
(1996)
1,25-dihydroxycholecalciferol inhibits the progression of arthritis in murine models of human arthritis
J Nutr
Ultraviolet B and blood pressure
Lancet
Circulating 25-hydroxyvitamin D levels indicative of vitamin D sufficiency: implications for establishing a new effective dietary intake recommendation for vitamin D
J Nutr
Too little vitamin D in premenopausal women: why should we care?
Am J Clin Nutr
Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women
Am J Clin Nutr
Redefining vitamin D insufficiency
Lancet
Optimal vitamin D status and serum parathyroid hormone concentrations in African American women
Am J Clin Nutr
Vitamin D and prevention of breast cancer:pooled analysis
J Steroid Mol Biol
Optimal vitamin D status for colorectal cancer prevention: a quantitative meta analysis
Am J Prev Med
Calcium and vitamin D supplements reduce tooth loss in the elderly
Am J Med
Why the optimal requirement for vitamin D3 is probably much higher than what is officially recommended for adults
J Steroid Biochem Mol Biol
Vitamin D supplementation, 25-hydroxyvitamin D concentrations, and safety
Am J Clin Nutr
Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol
Am J Clin Nutr
Vitamin D intake to attain a desired serum 25-hydroxy vitamin D concentration
Am J Clin Nutr
Evidence that vitamin D3 increases serum 25-hydroxyvitamin D more efficiently than does vitamin D2
Am J Clin Nutr
Vitamin D deficiency
N Engl J Med
Calcium absorption across epithelia
Physiol Rev
Chromosomal localization of two human genes involved in phosphate homeostasis: the type IIb sodium-phosphate cotransporter and stanniocalcin-2
Somat Cell Mol Genet
Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials
J Am Med Assoc
Past exposure to sun, skin phenotype, and risk of multiple sclerosis: case-control study
Br Med J
Geographic patterns of prostate cancer mortality. Evidence for a protective effect of ultraviolet radiation
Cancer
Geographic variation in breast cancer mortality in the United States: a hypothesis involving exposure to solar radiation
Prev Med
Effects of a short-term vitamin D3 and calcium supplementation on blood pressure and parathyroid hormone levels in elderly women
J Clin Endocrinol Metab
Secondary hyperparathyroidism in the elderly: means to defining hypovitaminosis D
Osteoporos Int
Low vitamin D and high parathyroid hormone levels as determinants of loss of muscle strength and muscle mass (sarcopenia): the longitudinal aging study Amsterdam
J Clin Endocrinol Metab
An RCT of vitamin D or placebo on falls in elderly women with low vitamin D status and a falling history
J Bone Miner Res
Effect of vitamin D on falls. A meta-analysis
J Am Med Assoc
Low-dose vitamin D prevents muscular atrophy and reduces falls ans hip fractures in women after stroke: a randomized controlled trial
Cerebrovasc Dis
Protein kinase C alpha modulates the Ca2 + influx phase of the Ca2 + response to 1-alpha, 25-dihydroxy-vitamin-D3 in skeletal muscle cells
Horm Metab Res
Do sunlight and vitamin D reduce the likelihood of colon cancer?
Int J Epidemiol
An estimate of premature cancer mortality in the US due to inadequate doses of solar ultraviolet-B-radiation
Cancer
Ecological study of solar radiation and cancer mortality in Japan
Health Phys
Prospective study of predictors of vitamin D status and cancer incidence and mortality in men
J Natl Cancer Inst
Relation of calcium, vitamin D, and dairy food intake to incidence of colon cancer among older women
Am J Epidemiol
Plasma vitamin D metabolites and risk of colorectal cancer in women
Cancer Epidemiol Biomarkers Prev.
Prostate cancer risk and prediagnostic serum 25-hydroxyvitamin D levels
Cancer Causes Control
Vitamin D intake and the risk for pancreatic cancer in two cohort studies
Cancer Epidemiol Biomarkers Prev
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Vitamin D new therapy for breast cancer prevention
2022, Oncogenic Viruses: Volume 2: Medical Applications of Viral Oncology ResearchImpact of vitamin D supplementation model on the circulating levels of 25 (OH) D in Algerian children aged 1–23 months
2020, Journal of Steroid Biochemistry and Molecular BiologyCitation Excerpt :The average value of this subgroup is 8.3 ± 0.9 μg/L. None of the children who received vitamin D supplement have a severe vitamin D deficiency. However, according to the new threshold of 25 (OH) D < 20 μg/L or 50 nmol/ L) [11,16], the prevalence of deficiency is 40% (n = 10/25) in the children’s group with non-supplement in vitamin D and 4% (n = 4/103) in the children’s group with vitamin D supplement (Table 1). The results of the study show the existence of a significant difference between the average serum concentrations of children’s groups with vitamin D supplement and non-supplement.
Implementation of automated testing for 1,25-dihydroxyvitamin D: Return of experience from a core-laboratory
2016, Clinical BiochemistryCitation Excerpt :Vitamin D is a key regulator of the bone and mineral metabolism and displays multiple extra-skeletal effects [1–3]. The 1,25 dihydroxyvitamin D (1,25(OH)2D) is the most biologically active form of vitamin D and exerts its function through the ubiquitous vitamin D receptor [2]. The production of 1,25(OH)2D is tightly regulated by parathyroid hormone, phosphate and calcium concentrations [3].
Implications of vitamin D deficiency in lithiasic patient and in general population
2015, Actas Urologicas EspanolasVitamin D and pregnancy
2013, Presse MedicaleVitamin D supplementation in older adults: Searching for specific guidelines in nursing homes
2013, Journal of Nutrition, Health and Aging