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Genetic and non-genetic correlates of vitamins K and D.\nShea MK, Benjamin EJ, Dupuis J, Massaro JM, Jacques PF, D'Agostino RB Sr, Ordovas JM, O'Donnell CJ, Dawson-Hughes B, Vasan RS, Booth SL.\nEur J Clin Nutr. 2007 Nov 21. [Epub ahead of print]\nPMID: 18030310 \ndoi: 10.1038/sj.ejcn\n\n

"THURSDAY, Dec. 3 (HealthDay News) -- New research points to the possibility of a genetic link between vitamin D and heart disease. People with high blood pressure who had a gene variant that reduces vitamin D activation in the body were found to be twice as likely as those without the variant to have congestive heart failure, the study found. The finding may lead to a way to identify people at increased risk for heart disease, according to Robert U. Simpson, an assistant professor of pharmacology at the University of Michigan Medical School and his research colleagues. They analyzed the genetic profiles of 617 people. One-third had hypertension, one-third had hypertension and congestive heart failure, and the remaining third served as healthy controls. The researchers found that a variant in the CYP27B1 gene was associated with congestive heart failure in people with hypertension. The study is in the November issue of Pharmacogenomics."

In conclusion, genetic variations of DBP are associated with insulin resistance in Japanese with normal glucose tolerance, which might contribute to the development of type 2 diabetes. Variations in vitamin D-binding protein (group-specific component protein) are associated with fasting plasma insulin levels in Japanese with normal glucose tolerance. Hirai M, Suzuki S, Hinokio Y, Hirai A, Chiba M, Akai H, Suzuki C, Toyota T. J Clin Endocrinol Metab. 2000 May;85(5):1951-3. PMID: 10843180

BACKGROUND: To determine the effect of vitamin D binding protein (DBP) genotypes on 25-hydroxyvitamin D [25(OH)D] changes with vitamin D supplements, we studied 98 adults receiving 600 or 4000 IU/d vitamin D(3) for one year. METHODS: The DBP functional variant, T436K, was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: Mean 25(OH)D increases were 97% for TT (n=48), 151% for TK (n=31) and 307% (n=6) for KK genotypes (p=.004). CONCLUSIONS: As with baseline 25(OH)D, T436K genotype predicts 25(OH)D changes after long-term vitamin D supplementation. Common genetic variants of the vitamin D binding protein (DBP) predict differences in response of serum 25-hydroxyvitamin D [25(OH)D] to vitamin D supplementation. Fu L, Yun F, Oczak M, Wong BY, Vieth R, Cole DE. Clin Biochem. 2009 Jul;42(10-11):1174-7. Epub 2009 Mar 18. PMID: 19302999

Environmental risk factors for autism: Do they help cause de novo genetic mutations that contribute to the disorder? Kinney DK, Barch DH, Chayka B, Napoleon S, Munir KM. Med Hypotheses. 2009 Aug 20. [Epub ahead of print] PMID: 19699591

Expression of the multiple sclerosis-associated MHC class II Allele HLA-DRB1*1501 is regulated by vitamin D.\nRamagopalan SV, Maugeri NJ, Handunnetthi L, Lincoln MR, Orton SM, Dyment DA, Deluca GC, Herrera BM, Chao MJ, Sadovnick AD, Ebers GC, Knight JC.\nPLoS Genet. 2009 Feb;5(2):e1000369. Epub 2009 Feb 6.\nPMID: 19197344 [

Vitamin D receptor allele combinations influence genetic susceptibility to type 1 diabetes in Germans. Pani MA, Knapp M, Donner H, Braun J, Baur MP, Usadel KH, Badenhoop K. Diabetes. 2000 Mar;49(3):504-7. PubMed PMID: 10868975. doi: 10.2337/diabetes.49.3.504

Childhood sun exposure influences risk of multiple sclerosis in monozygotic twins. Islam T, Gauderman WJ, Cozen W, Mack TM. Neurology. 2007 Jul 24;69(4):381-8. PMID: 17646631 Conclusion: Early sun avoidance seems to precede the diagnosis of multiple sclerosis (MS). This protective effect is independent of genetic susceptibility to MS.

Association study on two vitamin D receptor gene polymorphisms and vitamin D metabolites in multiple sclerosis. Smolders J, Damoiseaux J, Menheere P, Tervaert JW, Hupperts R. Ann N Y Acad Sci. 2009 Sep;1173:515-20. PMID: 19758194 DOI: 10.1111/j.1749-6632.2009.04656.x Discussion: We found no association of the Apal and Taql VDR gene SNPs with MS or with vitamin D metabolism in our population. Further research should assess the complex interaction between vitamin D, the VDR, and susceptibility to MS.

Paradigms and Paradoxes Last month Dr. Armin Zittermann of Ruhr University, Germany, published the best vitamin D paper of the month. He reviewed the mounting evidence that vitamin D deficiency is a major cause of heart disease. Zittermann A, Schleithoff SS, Koerfer R. Putting cardiovascular disease and vitamin D insufficiency into perspective. Br J Nutr. 2005 Oct;94(4):483-92. Before we start, let's talk about paradigms and paradoxes. A paradigm is a set of assumptions, concepts, and practices that constitutes a way of viewing reality. The current paradigm is that heart disease is caused by a combination of genetics, hypertension, diabetes, cholesterol, smoking, obesity, inactivity, and diet. A paradox is a fact that contradicts the paradigm.

Supplements of vitamin D at 'critical time periods' may be key to reducing the risk of multiple sclerosis, according to a new study from the UK and Canada. Researchers report that vitamin D may interact with a specific genetic component called HLA-DRB1*1501 that is known to increase the risk of multiple sclerosis by three-fold

"Numerous studies link Vitamin D and influenza, as well as Vitamin D and respiratory infections more generally. This vitamin up-regulates genetic expression of various endogenous antimicrobial peptides (AMP), which exhibit broad-spectrum microbicidal activity against bacteria, fungi, and viruses. Reports discussed below indicate that susceptibility to influenza is reduced with higher levels of sun exposure or vitamin D supplementation. Seasonal variation of vitamin D levels in humans can help explain the seasonality of flu epidemics."

The relevance of vitamin D receptor (VDR) gene polymorphisms for cancer: a review of the literature. Köstner K, Denzer N, Müller CS, Klein R, Tilgen W, Reichrath J. Anticancer Res. 2009 Sep;29(9):3511-36. Review. PMID: 19667145 CONCLUSION: Significant associations with VDR polymorphisms have been reported in cancer of the breast (Fok1, Bsm1, Taq1, Apa1, poly (A)), prostate (Fok1, Bsm1, Taq1, poly (A)), skin (Fok1, Bsm1, A-1210), colorectum (Fok1, Bsm1), ovary (Fok1, Apa1) and bladder (Fok1), and in renal cell carcinoma (Taq1, Apa1). However, conflicting data have been reported for most malignancies. After careful evaluation of the actual literature, it can be summarized that data indicating an association of VDR polymorphisms and cancer risk are strongest for breast cancer (Bsm1, Fok1), prostate cancer (Fok1) and malignant melanoma (MM) (Fok1). Data indicating an association of VDR polymorphisms and cancer prognosis are strongest for prostate cancer (Fok1), breast cancer (Bsm1, Taq1), MM (Bsm1) and renal cell carcinoma (Taq1).

Vitamin D receptor gene polymorphism: association with Crohn's disease susceptibility.\nSimmons JD, Mullighan C, Welsh KI, Jewell DP.\nGut. 2000 Aug;47(2):211-4.\nPMID: 10896912 \ndoi:10.1136/gut.47.2.211

Novel role of the vitamin D receptor in maintaining the integrity of the intestinal mucosal barrier. Kong J, Zhang Z, Musch MW, Ning G, Sun J, Hart J, Bissonnette M, Li YC. Am J Physiol Gastrointest Liver Physiol. 2008 Jan;294(1):G208-16. Epub 2007 Oct 25. PMID: 17962355 These observations suggest that VDR plays a critical role in mucosal barrier homeostasis by preserving the integrity of junction complexes and the healing capacity of the colonic epithelium. Therefore, vitamin D deficiency may compromise the mucosal barrier, leading to increased susceptibility to mucosal damage and increased risk of IBD.

Role of vitamin D in the pathogenesis of type 2 diabetes mellitus. Palomer X, González-Clemente JM, Blanco-Vaca F, Mauricio D. Diabetes Obes Metab. 2008 Mar;10(3):185-97. Review. PMID: 18269634 DOI: 10.1111/j.1463-1326.2007.00710.x Vitamin D deficiency has been shown to alter insulin synthesis and secretion in both humans and animal models. It has been reported that vitamin D deficiency may predispose to glucose intolerance, altered insulin secretion and type 2 diabetes mellitus. Vitamin D replenishment improves glycaemia and insulin secretion in patients with type 2 diabetes with established hypovitaminosis D, thereby suggesting a role for vitamin D in the pathogenesis of type 2 diabetes mellitus.

Our results of an association with the Fok1 VDR polymorphism further support a role of the vitamin D pathway in ovarian carcinogenesis. Polymorphisms in the vitamin D receptor and risk of ovarian cancer in four studies. Tworoger SS, Gates MA, Lee IM, Buring JE, Titus-Ernstoff L, Cramer D, Hankinson SE. Cancer Res. 2009 Mar 1;69(5):1885-91. Epub 2009 Feb 17. Erratum in: Cancer Res. 2009 Jun 15;69(12):5267. Gate, Margaret A [corrected to Gates, Margaret A]. PMID: 19223536 doi: 10.1158/0008-5472.CAN-08-3515

Review and meta-analysis on vitamin D receptor polymorphisms and cancer risk. Raimondi S, Johansson H, Maisonneuve P, Gandini S. Carcinogenesis. 2009 Jul;30(7):1170-80. Epub 2009 Apr 29. Review. PMID: 19403841

Why is it that vitamin D deficiency can manifest in so many different ways in different people? One big reason is something called vitamin D receptor (VDR) genotypes, the variation in the receptor for vitamin D. Why is it that the dose of vitamin D necessary to reach a specific level differs so widely from one person to the next? VDR genotype, again. Variation in blood levels of 25-hydroxy vitamin D from a specific dose of vitamin D can vary three-fold, as shown by a University of Toronto study. In other words, a dose of 4000 units per day may yield a 25-hydroxy vitamin D blood level of 30 ng/ml in Mary, 60 ng/ml in Paul, and 90 ng/ml in Pete--same dose, different blood levels