Plasma Concentrations Of Vitamin Research Articles

1α,25-dihydroxyvitamin D3 promotes osteogenic activity and downregulates proinflammatory cytokine expression in human periodontal ligament cells.

The aim of this study was to assess the impact of 1α,25-dihydroxyvitamin D3 (vitamin D3) on osteogenic and inflammatory properties of human periodontal ligament (PDL) cells and investigate underlying mechanisms. Human PDL cells, obtained from four subjects, were stimulated with vitamin D3 for 4-48h. The bone markers osteopontin and osteocalcin and proinflammatory cytokine/chemokine expression was determined by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Cytokine and chemokine expression was determined after stimulation with the inflammation promoter lipopolysaccharide (LPS) in the presence or absence of vitamin D3. Alkaline phosphatase activity was assessed using p-nitrophenylphosphate substrate. Treatment with 30ng/mL of vitamin D3, corresponding to an optimal plasma concentration of vitamin D, for 24h had no effect on PDL cell number and morphology but increased PDL cell osteopontin and osteocalcin mRNA expression by about 70 and 40%, respectively, and, moreover, treatment with vitamin D3 for 48h enhanced PDL cell alkaline phosphatase activity by about two times showing that vitamin D3 exerts pro-osteogenic effects in human PDL cells. Stimulation with LPS (1μg/mL) for 4h increased PDL cell interleukin (IL)-6 cytokine and chemokine ligand 1 (CXCL1) chemokine mRNA expression several fold. The LPS-induced increase in IL-6 and CXCL1 transcripts was attenuated by vitamin D3 (30ng/mL). Treatment with vitamin D3 (3-300ng/mL) for 24h reduced the LPS-evoked increase in PDL cell IL-6 protein by about 50%. Vitamin D3 (30ng/mL) had no effect on LPS-induced IL-1β and MCP-1 mRNA expression. Vitamin D3 promotes osteogenic differentiation but also downregulates inflammation promoter-induced IL-6 cytokine and CXCL1 chemokine expression in human PDL cells, suggesting that vitamin D3 both stimulates bone regeneration and antagonizes inflammation in human periodontal tissue.

Antioxidant Vitamin Supplementation Reduces Arterial Stiffness in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background:Several studies tested the effects of supplementation with antioxidant vitamins on arterial stiffness, but the results were contradictory. Objectives:The aim of our study was to conduct a systematic review and meta-analysis investigating the effect of antioxidant vitamins on arterial stiffness and to determine whether the effects on arterial stiffness vary according to dose, duration of intervention, and health or nutritional status of the included participants. Methods:We searched 3 databases (Medline, Embase, and Scopus) for articles that potentially met the following eligibility criteria: 1) randomized controlled trials comparing antioxidant vitamins (vitamins C, E, and A and β-carotene) to either placebo or no active control in 2) adult participants aged ≥18 y; 3) antioxidant vitamins administered alone or in combination, irrespective of dose, duration, and route of administration; and 4) changes in arterial stiffness or arterial compliance. Data were pooled as standardized mean differences (SMDs) and analyzed using fixed- and random-effects models. Results:Data synthesis showed that antioxidant vitamins reduced arterial stiffness significantly (SMD: −0.17; 95% CI: −0.26, −0.08; P < 0.001). This effect was significant in experimental (SMD: −1.02; 95% CI: −1.54, −0.49; P < 0.001) and primary prevention (SMD: −0.14; 95% CI: −0.24, −0.04; P < 0.01) studies, whereas a trend for reduced arterial stiffness was observed in studies including participants with diseases (SMD: −0.19; 95% CI: −0.40, 0.02; P = 0.08). Vitamin supplementation improved arterial stiffness irrespective of age group and duration of intervention. Antioxidant vitamins were more effective in participants with low baseline plasma concentrations of vitamins C (SMD: −0.35; 95% CI: −0.62, −0.07; P < 0.016) and E (SMD: −0.79; 95% CI: −1.23, −0.33; P < 0.01). Conclusions:Supplementation with antioxidant vitamins has a small, protective effect on arterial stiffness. The effect may be augmented in those with lower baseline plasma vitamin E and C concentrations. This trial was registered at PROSPERO as CRD42014007260.

Vitamin D status and PUFA ratios in a national representative cross-section of healthy, middle-aged Norwegian women—the Norwegian Women and Cancer Post-Genome Cohort.

Vitamin D and polyunsaturated fatty acids (PUFAs) are derived from partially overlapping sources. Vitamin D is produced in the skin after sun exposure, but is also derived from fatty fish and fish oils. Dietary PUFAs are mainly derived from plant oils that are rich in n-6 PUFAs, but fatty fish provides high amounts of the marine n-3 PUFAs. The Western diet provides an excess of n-6 PUFAs compared to n-3 PUFAs, and the ratios of these may influence human health. Here, we investigated the potential associations of plasma concentrations of vitamin D, marine PUFAs and PUFA ratios. Plasma concentrations of vitamin D (25(OH)D), marine PUFAs, and PUFA ratios were measured in 372 women from the Norwegian Women and Cancer (NOWAC) Post-Genome Cohort. Covariability was examined in 310 non-users of cod liver oil, using Spearman's rank correlation and linear regression. In non-users of cod liver oil, the average concentration of vitamin D was 40.3 nmol/L, and marine PUFA concentration was 0.2 mg/g. PUFA ratios were dominated by the n-6 fatty acids. Vitamin D levels were significantly associated with marine fatty acids and weakly associated with PUFA ratios. Concentrations of vitamin D and marine PUFAs were below recommended levels. The correlation analyses indicated that health-related effects of vitamin D and marine PUFAs respectively may be hard to separate in epidemiological studies. However, measured health effects of PUFA ratios and vitamin D are likely to derive from the influence of the two factors separately. The presented results are the first to show these associations in a nationally representative cohort.

Multivitamin restriction increases adiposity and disrupts glucose homeostasis in mice.

A strong association between obesity and low plasma concentrations of vitamins has been widely reported; however, the causality of this relationship is still not established. Our goal was to evaluate the impact of a multivitamin restriction diet (MRD) on body weight, adiposity and glucose homeostasis in mice. The mice were given a standard diet or a diet containing 50% of the recommended vitamin intake (MRD) for 12weeks. At the end of the experiment, total body weight was 6% higher in MRD animals than in the control group, and the adiposity of the MRD animals more than doubled. The HOMA-IR index of the MRD animals was significantly increased. The adipose tissue of MRD animals had lower expression of mRNA encoding adiponectin and Pnpla2 (47 and 32%, respectively) and 43% higher leptin mRNA levels. In the liver, the mRNA levels of Pparα and Pgc1α were reduced (29 and 69%, respectively) in MRD mice. Finally, the level of β-hydroxybutyrate, a ketonic body reflecting fatty acid oxidation, was decreased by 45% in MRD mice. Our results suggest that MRD promotes adiposity, possibly by decreasing adipose tissue lipolysis and hepatic β-oxidation. These results could highlight a possible role of vitamin deficiency in the etiology of obesity and associated disorders.

Physiological correlates of urbanization in a desert songbird.

Rapid worldwide urbanization is creating novel environments to which animals must adapt, a topic of growing interest for biologists. Studies of how organisms are affected by cities historically centered on large-scale censusing of populations, but recent investigations have considered finer-scaled, urban-rural differences among individuals and species in their behavior, morphology, and physiology, specifically as they relate to urban stress. A number of factors (e.g., corticosterone (CORT)-related stress response) may contribute to the degree of stress experienced by animals living under urban versus natural conditions, but several physiological variables have yet to be considered together in a large-scale assessment. Here, in a widespread species of desert passerine (the house finch, Haemorhous mexicanus), we quantified variation in plasma oxidative stress, plasma concentrations of vitamins and carotenoids, and body-mass of males in three successive seasons (winter, spring, and late summer/early fall) along an urban-rural gradient in Phoenix, Arizona, USA. We found that degree of urbanization was: (1) negatively related to circulating vitamin A concentrations in winter, (2) positively correlated with body-mass during spring, and (3) negatively associated with plasma concentrations of two carotenoids: zeaxanthin (during breeding) and 3-hydroxy-echinenone (3HE) (during molting). The striking link between 3HE levels and urbanization is consistent with previous research showing that urban songbirds have lower carotenoid levels and faded plumage; our finding is the first to implicate specific effects on a metabolically derived carotenoid for coloration. The fact that we observed only season-specific links between urbanization and indicators of quality in finches suggests that (at least for these metrics) there are no strong, lasting urban pressures imposed on finch physiology over the year. Interestingly, we found that a metric of plasma oxidative stress (lipid peroxidation) was positively correlated with levels of two carotenoids (lutein during breeding and 3HE during molting), which is consistent with a prior study of ours showing that finches with redder plumage deposit higher levels of CORT in their feathers; taken together, our studies suggest complex associations between carotenoids and stress.

Development of non‐invasive assessments on vitamin A status by using skin levels of carotenoids as biomarker – U.S. study (1022.8)

BACKGROUND: Vitamin A Deficiency (VAD) is a major problem leading to blindness and childhood mortality. An estimated 250 million preschool children are VAD and a substantial proportion of pregnant women are also VAD. The methods used today for the diagnosis of VAD are anthropometry and biomedical tests, which are costly and time‐consuming. A rapid, convenient, and cost‐effective method is needed to monitor vitamin A status and catch the early stage of VAD. Carotenoids are called pro‐vitamin A that can be distributed into the top layer of the skin, therefore, the skin may become a mirror reflecting vitamin A status. Noninvasive reflectance spectroscopy has been reported to measure carotenoid levels in the skin; its advantages are quick, convenient and low cost; the measurement takes less than 60 seconds. OBJECTIVE: The noninvasive method can not be directly applied to assess the vitamin A plasma concentration. Therefore, the first stage of my research is to collect the data from human subjects to find out the corrections between skin levels of carotenoids and plasma concentrations of vitamin A. METHODS: The plasma samples of 68 subjects were kindly provided by a local sponsor's study; all subjects received the non‐invasive measurements on their skin levels of carotenoids by using a reflectance scanner. The plasma samples were extracted and assayed by validated extraction and HPLC methods. The regression analysis was conducted with both skin and plasma data. RESULTS: Subjects with low reflectance scores had low plasma vitamin A contents. The skin levels of carotenoids are well‐correlated with the β‐carotene plasma concentrations (r2=0.63), and also the skin levels of carotenoids has a good correlation with the vitamin A plasma concentrations (r2=0.56). CONCLUSION: The noninvasive reflectance spectroscopy method is feasible to measure the vitamin A concentration in the blood, and more data from developing countries are needed to support the correlations.

Short‐ and long‐term changes in plasma vitamin and mineral concentrations following laparoscopic Roux‐en‐Y gastric bypass surgery (812.2)

Over 340,000 bariatric surgeries are performed annually worldwide, many of them on young individuals. While successful weight loss can occur, it has been associated with a number of nutritional deficiencies. In this prospective study, blood was taken from 21 female patients (19 White, 2 Black; age = 44.5 ± 2 yrs; body mass index (BMI) = 54.8 ± 1.7 kg/m2) at baseline and 3 wk, 3 mo., 6 mo. and 12 mo. after RYGB surgery to determine the extent to which select nutrient concentrations change over time. Average BMI at 12 mo. was 36.0 ± 1.4 kg/m2. At baseline, 47.7% were characterized by vitamin D (25OHD) &lt;20 ng/ml and 33.3% had 25OHD between 20‐30 ng/ml. By 12 mo., these levels represented 18% and 38.1% of the subjects, respectively. Iron status was lowest at 3 wks post‐surgery as evidenced by low plasma iron and high transferrin receptor levels. Inflammation was evident (hsCRP &gt;10 mg/ml) at baseline. The highest hsCRP level was observed at 3 wks post‐surgery and decreased over time. Consistent with an acute‐phase response, ferritin levels were highest at 3 wks post‐surgery. Plasma zinc levels were highest at 3 wks post‐surgery. None of the women were characterized with zinc deficiency (&lt;0.5 µg/ml). Prevalence of low copper status (&lt;0.8 µg/ml) at baseline was 14.3% and increased to 31.6% by 12 months. These data support the concept that short and long‐term changes in nutritional status are common after RYGB surgery.

Effect of systemic high dose vitamin C therapy on forearm blood flow reactivity during endotoxemia in healthy human subjects

ObjectiveAcute inflammation induced by administration of Escherichia coli lipopolysaccharide endotoxin (LPS) reduces plasma concentrations of vitamin C and impairs vascular endothelium-derived nitric oxide (NO) bioactivity. We tested the hypothesis that systemically administered high dose vitamin C restores the endogenous anti-oxidant potential and improves NO-dependent vasodilatation in the forearm vasculature. Design & setting36 male subjects were enrolled in this balanced, placebo controlled cross-over study. Forearm blood flow (FBF) reactivity to acetylcholine (ACh) and glyceryl-trinitrate (GTN), a sensitive test for endothelial function, was assessed at baseline and 4h after LPS-administration (20IU/kg i.v). The effect of two different doses of intravenous vitamin C (Vitamin C-Injektopas®), 320mg/kg and 480mg/kg over 2h, or placebo on forearm vascular function was studied after LPS. Main resultsLPS caused transient flu-like symptoms, decreased plasma vitamin C concentrations and reduced the ACh-dependent increase in FBF by up to 76%. Vitamin C at a mean plasma concentration of 3.2 or 4.9mmol/L restored the response to ACh compared to baseline. ConclusionHigh dose systemic vitamin C recovers LPS-induced endothelium-dependent vasodilation in the forearm resistance vasculature. This provides a rationale for a further clinical study of the systemic vitamin C effect under inflammatory conditions.

Effects of vitamin C administration on cholesterol gallstone formation

Biliary cholesterol is transported by vesicles and micelles. Cholesterol microcrystals are derived from thermodynamically unstable vesicles. In experimental animals vitamin C deficiency leads to a super-saturation of biliary cholesterol and to the formation of gallstones. To search for a possible relationship between serum levels of vitamin C and the formation of cholesterol gallstones in patients with cholelithiasis. Thirteen patients with cholelithiasis and a programmed surgical intervention were treated with 2 g/day of vitamin C per os for two weeks before surgery. Forty nine patients subjected to a cholecystectomy not supplemented with vitamin C were studied as controls. Plasma concentrations of vitamin C and lipid profiles were measured. The cholesterol saturation index, crystallization time, cholesterol and phospholipid content in vesicles and micelles, separated by gel filtration chromatography, were studied in bile samples obtained from the gallbladder. Vitamin C supplementation did not change significantly plasma lipids and bile lipid concentrations. However, in supplemented patients, significant reductions in vesicular cholesterol content (6.5 ± 4.8% compared to 17.9 ± 14.0% in the control group; p < 0.05) and vesicular cholesterol/phospholipid ratio (0.71 ± 0.53 compared to 1.36 ± 1.15 in controls; p < 0.05), were observed. Vitamin C administration may modify bile cholesterol crystallization process, the first step in cholesterol gallstone formation.

Massive and long-lasting decrease in vitamin C plasma levels as a consequence of extracorporeal circulation

ObjectiveThe use of cardiopulmonary bypass (CPB) is suggested to induce oxidative stress, reflected by an imbalance between prooxidant and antioxidant substances. The majority of studies published have either focused on only one aspect (prooxidant or antioxidant side) or covered only a short observation period. Therefore, the aim of this study was to investigate the long-term effects of CPB on the balance of prooxidative markers and antioxidant substances in one single group of patients, being able to estimate the degree of oxidative stress. MethodsBlood samples were taken from 29 patients undergoing cardiovascular surgery beginning the day before surgery through postoperative day 6 (discharge). Plasma concentrations of vitamins C (total ascorbic acid) and E and malondialdehyde were measured by high-performance liquid chromatography. Plasma levels of ascorbyl free radical were determined using electron paramagnetic resonance spectroscopy. ResultsThe study showed a significant decrease in vitamin C plasma levels during CPB without any recovery of vitamin C up to the time of discharge. Furthermore, CPB induced a significant increase in malondialdehyde plasma concentrations immediately after unclamping, accompanied by a significant increase in the ascorbyl free radical to total ascorbic acid ratio. The latter stayed elevated until the end of observation. ConclusionsOur findings indicate that the oxidative stress event after CPB can be divided into two phases: Immediately after reperfusion, a massive oxidative stress occurs, reflected by the increase in malondialdehyde. During convalescence, there must be an ongoing situation of oxidative stress, especially in the water-soluble compartment, leading to the consumption of vitamin C. Because the main antioxidant substance, vitamin C, did not increase again over the entire observation period, supplementation should be given consideration.

Prediagnostic plasma vitamin C and risk of gastric adenocarcinoma and esophageal squamous cell carcinoma in a Chinese population

China has some of the highest incidence rates for gastric adenocarcinoma (GA) and esophageal squamous cell carcinoma (ESCC) in the world. Prospective studies suggested that vitamin C may reduce risks; however, associations are unclear because of limited sample size. The objective was to examine the relation between prediagnostic plasma vitamin C and the risk of GA and ESCC. A case-cohort study was used to assess the association between prediagnostic plasma vitamin C and incidence of GA (n = 467) and ESCC (n = 618) in the General Population Nutrition Intervention Trial. With the use of multivariate Cox proportional hazards models, we estimated the HRs and 95% CIs. We also conducted a meta-analysis of the literature up to 1 October 2012 on the relation between circulating vitamin C and gastric cancer incidence. Two cohort studies and the current study were included to assess the body of evidence. For GA, each 20-μmol/L increase in plasma vitamin C was associated with a 14% decrease in risk (HR: 0.86; 95% CI: 0.76, 0.96). Compared with individuals with low plasma vitamin C concentrations (≤28 μmol/L), those with normal concentrations (>28 μmol/L) had a 27% reduced risk of GA (HR: 0.73; 95% CI: 0.56, 0.94). No association between vitamin C concentrations and ESCC was seen. Meta-analysis showed that the risk of incident GA among those with the highest concentration of plasma vitamin C was 31% lower (random-effects-pooled-odds ratio 0.69; 95% CI: 0.54, 0.89) than those in the lowest category. Our data provide evidence that higher circulating vitamin C was associated with a reduced risk of incident GA, but no association was seen for ESCC.

Fruit and vegetable intake and vitamins C and E are associated with a reduced prevalence of cataract in a Spanish Mediterranean population

BackgroundCataract is among the major causes of vision impairment and blindness worldwide. Epidemiological studies support the role of antioxidants in the etiology of cataract, but the evidence for one specific antioxidant over another is inconsistent. Few studies have examined the association of cataract with fruit and vegetable intake with inconclusive results. In the present study, the relationship between cataract and fruit and vegetable intake and dietary and blood levels of carotenoids, vitamins C and E were examined in a Spanish Mediterranean population.MethodsThe present work is an analysis of data from 599 elderly ( ≥ 65 years) participants from the Spanish segment of the EUREYE study. This is a European multi-center cross-sectional population-based study. Cataract was diagnosed using a slit-lamp examination and defined as any lens opacity in either eye or evidence of its removal (cataract extraction). Energy-adjusted intake of fruit and vegetables and antioxidant vitamins was estimated using a semi-quantitative food frequency questionnaire. Plasma concentrations of vitamin C were analyzed by a colorimetric method and carotenoids and α-tocopherol by a HPLC method. The associations between cataract and quartiles of fruit and vegetable intake and plasma antioxidants were investigated using logistic regression models.ResultsOf the 599 elderly recruited, 433 (73%) had cataract or cataract extraction, 54% were women and 46% were men. After adjustments, increasing quartiles of combined fruit and vegetable intake were associated with decreasing reduction of odds of cataract or cataract extraction, (P for trend = 0.008). Increasing quartiles of dietary intakes from 107 mg/d of vitamin C showed a significant decreasing association with prevalence of cataract or cataract extraction (P for trend = 0.047). For vitamin E, a protective association was found from intakes from 8 mg/d, but no linear trend was observed across quartiles of intake (P for trend = 0.944).ConclusionsHigh daily intakes of fruit and vegetables and vitamins C and E were associated with a significantly decreased of the prevalence of cataract or cataract surgery. This study reinforces the WHO recommendations on the benefits of diets rich in fruit and vegetables.

Hypovitaminosis D is associated with increased whole body fat mass and greater severity of non‐alcoholic fatty liver disease

Hypovitaminosis D is common in obesity and insulin-resistant states. Increased fat mass in patients with non-alcoholic fatty liver disease (NAFLD) may contribute to hypovitaminosis D. To determine the relation among plasma vitamin D concentration, severity of disease and body composition in NAFLD. Plasma vitamin D concentration was quantified in 148 consecutive biopsy-proven patients with NAFLD (non-alcoholic steatohepatitis - NASH: n=81; and hepatic steatosis: n=67) and healthy controls (n=39). NAFLD was scored using the NASH CRN criteria. Body composition was quantified by bioelectrical impedance analysis and abdominal CT image analysis. Plasma vitamin D concentration was significantly lower in NAFLD (21.2±10.4ng/ml) compared with healthy controls (35.7±6.0ng/ml). Higher NAFLD activity scores were associated with lower plasma concentration of vitamin D (r(2) =0.29; P<0.001). Subgroup analysis among patients with NAFLD showed that patients with NASH had significantly lower (P<0.01) vitamin D levels than those with steatosis alone (18.1±8.4 vs. 25.0±11.3ng/ml). Low concentrations of vitamin D were associated with greater severity of steatosis, hepatocyte ballooning and fibrosis (P<0.05).On multivariate regression analysis, only severity of hepatocyte ballooning was independently associated (P=0.02) with low vitamin D concentrations. Plasma vitamin D (P=0.004) and insulin concentrations (P=0.03) were independent predictors of the NAFLD activity score on biopsy. Patients with NAFLD had higher fat mass that correlated with low vitamin D (r(2) =0.26; P=0.008). Low plasma vitamin D concentration is an independent predictor of the severity of NAFLD. Further prospective studies demonstrating the impact of vitamin D replacement in NAFLD patients are required.

Docosahexaenoic and eicosapentaenoic acid supplementation does not exacerbate oxidative stress or intravascular haemolysis in homozygous sickle cell patients

We investigated whether or not Omega-3 long-chain polyunsaturated fatty acid (omega-3 LCPUFA) supplementation exacerbates oxidative stress in homozygous sickle cell patients aged 2 to 14 years. Depending on their age, they received between one and three omega-3 (277.8mg DHA and 39.0mg EPA/capsule) or placebo (high oleic acid sunflower seed oil) capsules for one year. Supplementation increased significantly the levels of the two fatty acids in red cell phosphatidylcholine and phosphatidylethanolamine (p<0.001). The patients who received omega-3 LCPUFA compared with their placebo-taking counterparts had a higher concentration of plasma vitamin E at one year (14.3±2.8 versus 12.3±2.8µmol/l; p<0.001). The two groups had comparable concentrations of the vitamin at six month intervention (10.8±2.2 versus 10.7±2.9µmol/l; p>0.05) and baseline (10.7±3.1 versus 10.7±2.8µmol/l; p>0.05). After six month of intervention, the patients on omega 3 fatty acids had lower GPx-1 (33.5±13.4 versus 46.6 ±17.6, p<0.01) and Cu/Zn-SOD (1070±600 versus 1470±690 p<0.05) activities than at baseline. GPx-1 (33.5±17.6IU/g Hb versus 43.7±13.2IU/g Hb; p<0.01) and Cu/Zn-SOD (1070±600IU/g Hb versus 1360±920IU/g Hb; p>0.05) activities were reduced in the omega 3 compared with the placebo at six month intervention. There was no difference in the activity of either of the enzymes between baseline and six month intervention in the placebo group (p>0.05). This study demonstrates; DHA and EPA supplementation, rather than exacerbating the inherent oxidative stress associated with the disease, seems to provide an antioxidant protection. Hence, it will be safe to provide omega-3 LCPUFA to sickle cell patients to help ameliorate vaso-occlusive and haemolytic crises and membrane fatty acid abnormality.

Increased Plasma Concentrations of Vitamin D Metabolites and Vitamin D Binding Protein in Women Using Hormonal Contraceptives: A Cross-Sectional Study

Use of hormonal contraceptives (HC) may influence total plasma concentrations of vitamin D metabolites. A likely cause is an increased synthesis of vitamin D binding protein (VDBP). Discrepant results are reported on whether the use of HC affects free concentrations of vitamin D metabolites. Aim: In a cross-sectional study, plasma concentrations of vitamin D metabolites, VDBP, and the calculated free vitamin D index in users and non-users of HC were compared and markers of calcium and bone metabolism investigated. Results: 75 Caucasian women aged 25–35 years were included during winter season. Compared with non-users (n = 23), users of HC (n = 52) had significantly higher plasma concentrations of 25-hydroxyvitamin D (25OHD) (median 84 interquartile range: [67-111] vs. 70 [47-83] nmol/L, p = 0.01), 1,25-dihydroxyvitamin D (1,25(OH)2D) (198 [163-241] vs. 158 [123-183] pmol/L, p = 0.01) and VDBP (358 [260-432] vs. 271 [179-302] µg/mL, p < 0.001). However, the calculated free indices (FI-25OHD and FI-1,25(OH)2D) were not significantly different between groups (p > 0.10). There were no significant differences in indices of calcium homeostasis (plasma concentrations of calcium, parathyroid hormone, and calcitonin, p > 0.21) or bone metabolism (plasma bone specific alkaline phosphatase, osteocalcin, and urinary NTX/creatinine ratio) between groups. In conclusion: Use of HC is associated with 13%–25% higher concentrations of total vitamin D metabolites and VDBP. This however is not reflected in indices of calcium or bone metabolism. Use of HC should be considered in the interpretation of plasma concentrations vitamin D metabolites.

Circulating levels of 25-hydroxyvitamin D and prostate cancer prognosis

Objectives: Ecological, in vitro, and in vivo studies demonstrate a link between vitamin D and prostate tumor growth and aggressiveness. The goal of this study was to investigate whether plasma concentration of vitamin D is associated with survivorship and disease progression in men diagnosed with prostate cancer. Materials and methods: We conducted a population-based cohort study of 1476 prostate cancer patients to assess disease recurrence/progression and prostate cancer-specific mortality (PCSM) risks associated with serum levels of 25(OH) vitamin D [25(OH)D]. Results: There were 325 recurrence/progression and 95 PCSM events during an average of 10.8 years of follow-up. Serum levels of 25(OH)D were not associated with risk of recurrence/progression or mortality. Clinically deficient vitamin D levels were associated with an increased risk of death from other causes. Conclusions: We did not find evidence that serum vitamin D levels measured after diagnosis affect prostate cancer prognosis. Lower levels of vitamin D were associated with risk of non-prostate cancer mortality.

Race-Ethnicity Is a Strong Correlate of Circulating Fat-Soluble Nutrient Concentrations in a Representative Sample of the U.S. Population

Sociodemographic and lifestyle factors exert important influences on nutritional status; however, information on their association with biomarkers of fat-soluble nutrients is limited, particularly in a representative sample of adults. Serum or plasma concentrations of vitamin A, vitamin E, carotenes, xanthophylls, 25-hydroxyvitamin D [25(OH)D], SFAs, MUFAs, PUFAs, and total fatty acids (tFAs) were measured in adults (aged ≥20 y) during all or part of NHANES 2003–2006. Simple and multiple linear regression models were used to assess 5 sociodemographic variables (age, sex, race-ethnicity, education, and income) and 5 lifestyle behaviors (smoking, alcohol consumption, BMI, physical activity, and supplement use) and their relation to biomarker concentrations. Adjustment for total serum cholesterol and lipid-altering drug use was added to the full regression model. Adjustment for latitude and season was added to the full model for 25(OH)D. Based on simple linear regression, race-ethnicity, BMI, and supplement use were significantly related to all fat-soluble biomarkers. Sociodemographic variables as a group explained 5–17% of biomarker variability, whereas together, sociodemographic and lifestyle variables explained 22–23% [25(OH)D, vitamin E, xanthophylls], 17% (vitamin A), 15% (MUFAs), 10–11% (SFAs, carotenes, tFAs), and 6% (PUFAs) of biomarker variability. Although lipid adjustment explained additional variability for all biomarkers except for 25(OH)D, it appeared to be largely independent of sociodemographic and lifestyle variables. After adjusting for sociodemographic, lifestyle, and lipid-related variables, major differences in biomarkers were associated with race-ethnicity (from −44 to 57%), smoking (up to −25%), supplement use (up to 21%), and BMI (up to −15%). Latitude and season attenuated some race-ethnicity differences. Of the sociodemographic and lifestyle variables examined, with or without lipid adjustment, most fat-soluble nutrient biomarkers were significantly associated with race-ethnicity.

High dose IV vitamin C for treatment of prostate adenocarcinoma

Prostate cancer is one of the common cancers seen in males. Earlier studies that have used intravenous (IV) or oral vitamin C have shown an improvement in symptoms of cancer patients and have prolonged life in terminally ill cancer patients. Today, evidence suggests that high doses of intravenous vitamin C ranging from 50 to 100 g can increase the plasma concentration of vitamin C to 14000 μmol/L. When the concentration of vitamin C in the plasma is about 1000 μmol/L, vitamin C is selectively toxic to cancer cells. We report here a case study of a patient who has diagnosed prostate cancer of Gleason's pattern 7. We found that, at the end of ten months of treatment with high dose IV vitamin C, the vascular tumor that was present before on the left mid-gland area of the prostate was no longer detectable on the ultrasound. In the light of the recent evidence showing anti-tumor activity of vitamin C, the role of high dose IV vitamin C for cancer should be considered further.

Activation of RelA (p65), but not of p50 dimers of nuclear factor kappa B (NF‐κB) is decreased in impaired renal function

The NF‐κB signaling pathway plays a central role in chronic inflammation and is an important interface between inflammation and oxidative stress. The heterodimer RelA (p65) ‐ p50 is the most abundant transcription factor of the NF‐κB family. Decreased activation of RelA has been found in different pathologies. The purpose of this study of the BIOCLAIMS project was to investigate the activation of both the RelA and p50 dimers in individuals with different stages of renal function. Peripheral blood mononuclear cells (PBMC) were collected from 362 study subjects with glomerular filtration rate (GFR, MDRD) of 18–123 mL/min/1.73 m2. Activation of NF‐κB dimers containing RelA and p50 was determined using an ELISA‐based assay (TransAM, Active Motif). Linear regression analysis showed that activation of RelA‐containing NF‐κB dimers decreased significantly with decreasing GFR (r = 0.171, P = 0.001), while activation of p50‐containing NF‐κB dimers increased significantly with decreasing GFR (r = − 0.148, P = 0.005). Antioxidant status, including plasma concentrations of vitamin C, α‐ and γ‐tocopherol and β‐carotene did not explain NF‐κB activation beyond kidney function. To our knowledge this is the first report on differential effects of impaired renal function on RelA and p50 activation. The underlying mechanisms of these findings need to be further elucidated.Grant Funding Source: Supported by European Commission, FP7, contract 244995, and Austrian Government (bmwf).

Effect of Antioxidants and B-Group Vitamins on Risk of Infections in Patients with Type 2 Diabetes Mellitus

Previous studies have revealed that diabetic patients have a decline in immunity and an increased risk of infections, and this may be associated with poor micronutrient status. The aim of this study was to measure the effect of dietary supplements on risk of infection in patients with type 2 diabetes mellitus. One hundred patients with type 2 diabetes mellitus were randomly assigned to receive an oral dose of daily B-group vitamins and antioxidant vitamins (n = 50) or an identical placebo (n = 50) daily for 90 days. Patients had baseline, three and 12 month assessment for nutritional status, fruits and vegetables intake, physical activity and self-reported infections. Supplementation with antioxidants and B-group vitamins significantly increased the plasma concentration of vitamin E and folate and reduced homocysteine in the intervention group (p-values were 0.006, 0.001 and 0.657, respectively). The number of infections reported by the treatment group after three months of supplements was less than that reported by the placebo group, 9 (27%) vs. 15 (36%) (p = 0.623). Corresponding numbers of infections at 12 months were 25 (67.5%) and 27 (56.3%), respectively (p = 0.488). Up to 90% of the diabetic patients were either overweight or obese with a sedentary life style, and their body weight increased further during three months of follow up. The study showed that multivitamin supplements improved vitamin blood concentrations; however, this did not reduce the number of infections in diabetic patients.