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Matti Narkia

Vitamin D and Vitamin K Team Up to Lower CVD Risk - Part I - 1 views

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    Strong correlations have been noted between cardiovascular diseases and low bone density / osteoporosis-connections so strong that the presence of one type of pathology is considered a likely predictor of the other. This potentially causal relationship has led to the hypothesis that these conditions share core mechanisms. Recent advances in our understanding of the complimentary roles played by vitamin D3 and vitamin K2 in vascular and bone health provide support for this hypothesis, along with insight into key metabolic dysfunctions underlying cardiovascular disease and osteoporosis. Part I of this review summarizes current research linking vitamin D deficiency to cardiovascular disease, the physiological mechanisms underlying vitamin D's cardiovascular effects, and leading vitamin D researchers' recommendations for significantly higher supplemental doses of the pro-hormone. Part II reviews the vitamin K connection to cardiovascular disease; the ways in which vitamin D and vitamin K pair up to prevent inflammation, vascular calcification and osteoporosis; and the necessity of providing vitamin K along with vitamin D to preclude adverse effects associated with hypervitaminosis D, which include vascular and other soft tissue calcification.
Matti Narkia

Vitamin D toxicity redefined: Vitamin K and the molecular mechanism - 0 views

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    Vitamin D toxicity redefined: vitamin K and the molecular mechanism. Masterjohn C. Med Hypotheses. 2007;68(5):1026-34. Epub 2006 Dec 4. PMID: 17145139 doi:10.1016/j.mehy.2006.09.051
Matti Narkia

Effects of Atorvastatin on Vitamin D Levels in Patients With Acute Ischemic Heart Disease - 0 views

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    Effects of Atorvastatin on vitamin D levels in patients with acute ischemic heart disease. Pérez-Castrillón JL, Vega G, Abad L, Sanz A, Chaves J, Hernandez G, Dueñas A. Am J Cardiol. 2007 Apr 1;99(7):903-5. Epub 2007 Feb 8. PMID: 17398180 In conclusion, atorvastatin increases vitamin D levels. This increase could explain some of the beneficial effects of atorvastatin at the cardiovascular level that are unrelated to cholesterol levels. The mechanism by which atorvastatin increases vitamin D levels is related to inhibition of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase. Cholesterol is synthesized from 7-dehydrocholesterol, which is also a precursor of vitamin D3. For this reason, we initially observed a statistically significant relation between total cholesterol and vitamin D. HMG-CoA enzyme reductase is key to the synthesis of cholesterol, whereas ultraviolet radiation causes the formation of 25-hydroxyvitamin D. Inhibition of the enzyme may increase levels of 7-dehydrocholesterol and increase the synthesis of 25-hydroxycholecalciferol, thereby increasing vitamin D levels,10 although we observed no relation between lower cholesterol and increased vitamin D. In addition, 25-hydroxyvitamin D has been shown to inhibit HMG-CoA enzyme reductase activity in in vitro studies.11 A greater concentration of vitamin D could increase enzymatic inhibition, acting in synergy with the statin in decreasing total cholesterol.
Matti Narkia

Why Low Vitamin D Raises Heart Disease Risks In Diabetics - 0 views

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    ScienceDaily (Aug. 25, 2009) - Low levels of vitamin D are known to nearly double the risk of cardiovascular disease in patients with diabetes, and researchers at Washington University School of Medicine in St. Louis now think they know why. They have found that diabetics deficient in vitamin D can't process cholesterol normally, so it builds up in their blood vessels, increasing the risk of heart attack and stroke. The new research has identified a mechanism linking low vitamin D levels to heart disease risk and may lead to ways to fix the problem, simply by increasing levels of vitamin D.
Matti Narkia

Vitamin D supplementation improves neuromuscular function in older people who fall -- D... - 0 views

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    Vitamin D supplementation improves neuromuscular function in older people who fall. Dhesi JK, Jackson SH, Bearne LM, Moniz C, Hurley MV, Swift CG, Allain TJ. Age Ageing. 2004 Nov;33(6):589-95. PMID: 15501836 doi:10.1093/ageing/afh20 9 CONCLUSIONS: vitamin D supplementation, in fallers with vitamin D insufficiency, has a significant beneficial effect on functional performance, reaction time and balance, but not muscle strength. This suggests that vitamin D supplementation improves neuromuscular or neuroprotective function, which may in part explain the mechanism whereby vitamin D reduces falls and fractures.
Matti Narkia

Vitamin D and Type 2 Diabetes - Diabetes - 0 views

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    Vitamin D and type 2 diabetes: are we ready for a prevention trial? Scragg R. Diabetes. 2008 Oct;57(10):2565-6. PMID: 18820212 doi: 10.2337/db08-0879 Despite evidence from the current article (3) and the Finnish study (17), doubts still remain about whether low vitamin status is a cause of type 2 diabetes. Further cohort studies are required, assessing baseline vitamin D status using blood 25(OH)D to be sure that the Ely and Finnish studies are not false-positive results. Glucose clamp studies are also required because we are still not sure of the mechanism influenced by vitamin D-whether it is insulin resistance, secretion, or both. But most importantly, given that nearly three decades have passed since the first studies linking vitamin D with insulin metabolism (6,7), well-designed clinical trials of the effect of vitamin D supplementation on glycemia status and diabetes risk are urgently required to settle this question. And they need to prevent past mistakes. In particular, the vitamin D dose given in such trials needs to be high enough-above 2,000 IU per day (19)-to raise blood 25(OH)D levels above 80 nmol/l because diabetes risk is lowest at this level (9,20). If well-designed trials are carried out and confirm a protective effect from vitamin D, it could be used by the general population as a simple and cheap solution to help prevent the diabetes epidemic.
Matti Narkia

Serum 25-Hydroxyvitamin D Levels and the Prevalence of Peripheral Arterial Disease: Res... - 0 views

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    Serum 25-hydroxyvitamin D levels and the prevalence of peripheral arterial disease: results from NHANES 2001 to 2004. Melamed ML, Muntner P, Michos ED, Uribarri J, Weber C, Sharma J, Raggi P. Arterioscler Thromb Vasc Biol. 2008 Jun;28(6):1179-85. Epub 2008 Apr 16. PMID: 18417640 doi: 10.1161/ATVBAHA.108.165886 Conclusions- Low serum 25(OH)D levels are associated with a higher prevalence of PAD. Several mechanisms have been invoked in the literature to support a potential antiatherosclerotic activity of vitamin D. Prospective cohort and mechanistic studies should be designed to confirm this association. Vitamin D is an inhibitor of the renin-angiotensin system and has antiinflammatory and anticoagulant properties. Among 4839 NHANES 2001 to 2004 participants, low 25(OH)D levels were associated with a higher prevalence of PAD, after multivariate adjustment. To confirm this association, longitudinal cohort and mechanistic studies are needed.
Matti Narkia

Hypovitaminosis D is associated with insulin resistance and {beta} cell dysfunction -- ... - 0 views

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    Hypovitaminosis D is associated with insulin resistance and beta cell dysfunction. Chiu KC, Chu A, Go VL, Saad MF. Am J Clin Nutr. 2004 May;79(5):820-5. PMID: 15113720 Conclusions: The data show a positive correlation of 25(OH)D concentration with insulin sensitivity and a negative effect of hypovitaminosis D on ß cell function. Subjects with hypovitaminosis D are at higher risk of insulin resistance and the metabolic syndrome. Further studies are required to explore the underlying mechanisms.
Matti Narkia

1,25(OH)2 Vitamin D Inhibits Foam Cell Formation and Suppresses Macrophage Cholesterol ... - 0 views

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    1,25(OH)2 vitamin d inhibits foam cell formation and suppresses macrophage cholesterol uptake in patients with type 2 diabetes mellitus. Oh J, Weng S, Felton SK, Bhandare S, Riek A, Butler B, Proctor BM, Petty M, Chen Z, Schechtman KB, Bernal-Mizrachi L, Bernal-Mizrachi C. Circulation. 2009 Aug 25;120(8):687-98. Epub 2009 Aug 10. PMID: 19667238 doi: 10.1161/CIRCULATIONAHA.109.856070 Conclusion- These results identify reduced vitamin D receptor signaling as a potential mechanism underlying increased foam cell formation and accelerated cardiovascular disease in diabetic subjects.
Matti Narkia

Vitamin D and its role in skeletal muscle. [Curr Opin Clin Nutr Metab Care. 2009] - Pub... - 0 views

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    Vitamin D and its role in skeletal muscle. Ceglia L. Curr Opin Clin Nutr Metab Care. 2009 Sep 18. [Epub ahead of print] PMID: 19770647 SUMMARY: Further studies are needed to fully characterize the underlying mechanisms of vitamin D action in human muscle tissue, to understand how these actions translate into changes in muscle cell morphology and improvements in physical performance, and to define the 25-hydroxyvitamin D level at which to achieve these beneficial effects in muscle.
Matti Narkia

Vitamin D and Vitamin K Team Up to Lower CVD Risk - Part II - 0 views

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    Strong correlations have been noted between cardiovascular diseases and low bone density / osteoporosis-connections so strong that the presence of one is considered a likely predictor of the other. This relationship has led to the hypothesis that these conditions share core pathophysiological mechanisms. Recent advances in our understanding of the complimentary roles played by vitamin D3 and vitamin K2 in vascular and bone health provide support for this hypothesis, along with insight into key metabolic dysfunctions underlying cardiovascular disease and osteoporosis. Part II, The Vitamin K Connection to Cardiovascular Health, reviews the ways in which vitamin K regulates calcium utlization, preventing vascular and soft tissue calcification while complimenting the bone-building actions of vitamin D, and also discusses vitamin K safety and dosage issues, and the necessity of providing vitamin K and vitamin A along with vitamin D to preclude adverse effects associated with hypervitaminosis D.
Matti Narkia

JNNP -- eLetters for Soilu-Hänninen et al., 79 (2) 152-157 - 0 views

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    Vitamin D may suppress infections which lead to development of Multiple Sclerosis Steven R Brenner, None (16 August 2007) J Neurol Neurosurg Psychiatry 2008 I read the article with reference to the inverse relationship between multiple sclerosis clinical activity and deficiency of vitamin D by Soilu-Hannienen (1) with interest, and was considering what mechanism could be in play to cause such a relationship. 25-hydroxylated metabolites of vitamin D act as intracellular regulators of the synthesis and action of defensin (2) molecules against bacterial antigens, defensin being an endogenously synthesized antimicrobial substance (2). Human cathelicidin antimicrobial peptide gene is a target of vitamin D receptor and is strongly up-regulated by 1,25-dihydroxyvitamin D3, indicating vitamin D receptor and the 1,25-dihydroxyvitaminD3 regulate primate innate immunity (3)
Matti Narkia

YouTube - Vitamin D and Cancer Prevention - 0 views

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    YouTube - Vitamin D and Cancer Prevention. A presentation by Dr. Cedric Garland.
Matti Narkia

Use of vitamin D in clinical practice. - Altern Med Rev. 2008 Mar - 0 views

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    Use of vitamin D in clinical practice. Cannell JJ, Hollis BW. Altern Med Rev. 2008 Mar;13(1):6-20. PMID: 18377099 The recent discovery--from a meta-analysis of 18 randomized controlled trials--that supplemental cholecalciferol (vitamin D) significantly reduces all-cause mortality emphasizes the medical, ethical, and legal implications of promptly diagnosing and adequately treating vitamin D deficiency. Not only are such deficiencies common, and probably the rule, vitamin D deficiency is implicated in most of the diseases of civilization. Vitamin D's final metabolic product is a potent, pleiotropic, repair and maintenance, seco-steroid hormone that targets more than 200 human genes in a wide variety of tissues, meaning it has as many mechanisms of action as genes it targets. One of the most important genes vitamin D up-regulates is for cathelicidin, a naturally occurring broad-spectrum antibiotic. Natural vitamin D levels, those found in humans living in a sun-rich environment, are between 40-70 ng per ml, levels obtained by few modern humans. Assessing serum 25-hydroxy-vitamin D (25(OH)D) is the only way to make the diagnosis and to assure treatment is adequate and safe. Three treatment modalities exist for vitamin D deficiency: sunlight, artificial ultraviolet B (UVB) radiation, and vitamin D3 supplementation. Treatment of vitamin D deficiency in otherwise healthy patients with 2,000-7,000 IU vitamin D per day should be sufficient to maintain year-round 25(OH)D levels between 40-70 ng per mL. In those with serious illnesses associated with vitamin D deficiency, such as cancer, heart disease, multiple sclerosis, diabetes, autism, and a host of other illnesses, doses should be sufficient to maintain year-round 25(OH)D levels between 55 -70 ng per mL. Vitamin D-deficient patients with serious illness should not only be supplemented more aggressively than the well, they should have more frequent monitoring of serum 25(OH)D and serum calcium. Vitamin D should always be
Matti Narkia

Vitamin D and multiple sclerosis. - Wiley InterScience - J Cell Biochem. 2008 Oct 1 - 0 views

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    Vitamin D and multiple sclerosis. Raghuwanshi A, Joshi SS, Christakos S. J Cell Biochem. 2008 Oct 1;105(2):338-43. Review. PMID: 18655192
Matti Narkia

Vitamin D and cancer Ali MM, Vaidya V - J Can Res Ther 2007 Oct-Dec - 0 views

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    Vitamin D and cancer. Ali MM, Vaidya V. J Cancer Res Ther. 2007 Oct-Dec;3(4):225-30. Review. PMID: 18270398 DOI: 10.4103/0973-1482.38998
Matti Narkia

Diagnosis and treatment of vitamin D deficiency; Expert Opinion on Pharmacotherapy - 9(... - 0 views

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    Diagnosis and treatment of vitamin D deficiency. Cannell JJ, Hollis BW, Zasloff M, Heaney RP. Expert Opin Pharmacother. 2008 Jan;9(1):107-18. PMID: 18076342 The recent discovery - in a randomised, controlled trial - that daily ingestion of 1100 IU of colecalciferol (vitamin D) over a 4-year period dramatically reduced the incidence of non-skin cancers makes it difficult to overstate the potential medical, social and economic implications of treating vitamin D deficiency. Not only are such deficiencies common, probably the rule, vitamin D deficiency stands implicated in a host of diseases other than cancer. The metabolic product of vitamin D is a potent, pleiotropic, repair and maintenance, secosteroid hormone that targets > 200 human genes in a wide variety of tissues, meaning it has as many mechanisms of action as genes it targets. A common misconception is that government agencies designed present intake recommendations to prevent or treat vitamin D deficiency. They did not. Instead, they are guidelines to prevent particular metabolic bone diseases. Official recommendations were never designed and are not effective in preventing or treating vitamin D deficiency and in no way limit the freedom of the physician - or responsibility - to do so. At this time, assessing serum 25-hydroxy-vitamin D is the only way to make the diagnosis and to assure that treatment is adequate and safe. The authors believe that treatment should be sufficient to maintain levels found in humans living naturally in a sun-rich environment, that is, > 40 ng/ml, year around. Three treatment modalities exist: sunlight, artificial ultraviolet B radiation or supplementation. All treatment modalities have their potential risks and benefits. Benefits of all treatment modalities outweigh potential risks and greatly outweigh the risk of no treatment. As a prolonged 'vitamin D winter', centred on the winter solstice, occurs at many temperate latitudes, ≤ 5000 IU (125 μg) of vitamin D/d
Matti Narkia

Vitamin D and mood disorders among women: an integrative review. - [J Midwifery Womens ... - 0 views

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    Vitamin D and mood disorders among women: an integrative review. Murphy PK, Wagner CL. J Midwifery Womens Health. 2008 Sep-Oct;53(5):440-6. Review. PMID: 18761297 Four of six studies reviewed imparted significant results, with all four showing an association between low 25(OH)D levels and higher incidences of four mood disorders: premenstrual syndrome, seasonal affective disorder, non-specified mood disorder, and major depressive disorder. This review indicates a possible biochemical mechanism occurring between vitamin D and mood disorders affecting women, warranting further studies of these variables using rigorous methodologies.
Matti Narkia

Calcium and vitamin D intakes may be positively associated with brain lesions in depres... - 0 views

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    Calcium and vitamin D intakes may be positively associated with brain lesions in depressed and nondepressed elders. Payne ME, Anderson JJ, Steffens DC. Nutr Res. 2008 May;28(5):285-92. PMID: 19083421 doi: 10.1016/j.nutres.2008.02.013 In conclusion, calcium and vitamin D consumption were associated with brain lesions in elderly subjects even after controlling for potentially explanatory variables. These associations may be due to vascular calcification or other mechanism. The possibility of adverse effects of high intakes of calcium and vitamin D needs to be further explored in longitudinal studies of elderly subjects.
Matti Narkia

Vitamin D association with estradiol and progesterone in young women. - [Cancer Causes ... - 0 views

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    Vitamin D association with estradiol and progesterone in young women. Knight JA, Wong J, Blackmore KM, Raboud JM, Vieth R. Cancer Causes Control. 2009 Nov 15. [Epub ahead of print] PMID: 19916051 CONCLUSIONS: Higher levels of vitamin D may reduce progesterone and estradiol, providing a potential mechanism for reduction in breast cancer risk from increased vitamin D exposure in young women.
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