Serum 25-hydroxyvitamin D3 Concentration Research Articles

A study on the effects of vitamin D supplementation on hematological parameters and serum 25-hydroxy vitamin D in healthy dogs

BackgroundLimited studies are available on vitamin D supplementation in dogs. This study evaluates the effect of a commercial vitamin D3 supplement on serum 25-hydroxy vitamin D as well as selected biochemical and hematological parameters in healthy dogs. Eight intact male adult dogs with a mean body weight of 20 kg from mixed breeds were included in the study. After adaptation period, dogs received vitamin D3 supplement at the dose of 50 IU/kg body weight per day. Blood samples were collected on days 0, 14, 28 and 42 of supplementation. Food was used for analysis of vitamin D3 content.ResultsSignificant increase in serum level of 25-hydroxy vitamin D3 was detected since day 14 of supplementation. Changes in serum 25-hydroxy vitamin D3 concentration during time showed an upward significance (p < 0.05). Vitamin D3 content of the food was 2900 IU/kg dry matter. Changes in serum phosphorus levels were upward significant. No dog showed calcium or phosphorus levels above the highest reference level. Liver and kidney parameters remained in the reference range during the experiment. A gradual significant increase was observed in hemoglobin and hematocrit which was started from day 14. Vitamin D3 supplementation had no significant effect on neutrophils, monocytes and lymphocytes percent during the study.ConclusionsVitamin D3 supplementation at 50 IU/kg BW daily, increases serum levels of 25-hydroxy vitamin D in healthy dogs fed with a diet containing proper amount of this vitamin. It also increases hemoglobin and hematocrit levels in a time dependent manner without inducing adverse effects.

Association between vitamin D and endometriosis among American women: National Health and Nutrition Examination Survey.

Endometriosis is a multifactorial disease associated with inflammation. Vitamin D has anti-inflammatory, antiproliferative, anti-oxidative, and immunomodulatory effects. Whether vitamin D levels are correlated with endometriosis is a subject of ongoing debate. This study aimed to examine the association between endometriosis and serum vitamin D levels. From the National Health and Nutrition Examination Survey, this study examined the cross-sectional data of American women aged 20-54 years from 2001 to 2006. After adjusting for covariates, multivariable logistic regression analysis was used to assess correlations. A total of 3,232 women were included in this study. The multiple linear regression model demonstrated a negative correlation between the serum 25-hydroxyvitamin D3 (cholecalciferol) concentration and the risk of endometriosis after controlling for all confounding variables. The odds ratio was 0.73 with a 95% confidence interval of 0.54-0.97 in the adequate vitamin D level group compared with the insufficient vitamin D level group. Our results showed that endometriosis was inversely correlated with serum 25-hydroxyvitamin D3 levels. Further research is needed to establish a causal relationship and determine the potential benefits of maintaining sufficient vitamin D levels for endometriosis prevention.

Supplementation with Vitamin D3 Protects against Mitochondrial Dysfunction and Loss of BDNF-Mediated Akt Activity in the Hippocampus during Long-Term Dexamethasone Treatment in Rats.

Dexamethasone (DEXA) is a commonly used steroid drug with immunosuppressive and analgesic properties. Unfortunately, long-term exposure to DEXA severely impairs brain function. This study aimed to investigate the effects of vitamin D3 supplementation during chronic DEXA treatment on neurogenesis, mitochondrial energy metabolism, protein levels involved in the BDNF-mediated Akt activity, and specific receptors in the hippocampus. We found reduced serum concentrations of 25-hydroxyvitamin D3 (25(OH)D3), downregulated proBDNF and pAkt, dysregulated glucocorticosteroid and mineralocorticoid receptors, impaired mitochondrial biogenesis, and dysfunctional mitochondria energy metabolism in the DEXA-treated group. In contrast, supplementation with vitamin D3 restored the 25(OH)D3 concentration to a value close to that of the control group. There was an elevation in neurotrophic factor protein level, along with augmented activity of pAkt and increased citrate synthase activity in the hippocampus after vitamin D3 administration in long-term DEXA-treated rats. Our findings demonstrate that vitamin D3 supplementation plays a protective role in the hippocampus and partially mitigates the deleterious effects of long-term DEXA administration. The association between serum 25(OH)D3 concentration and BDNF level in the hippocampus indicates the importance of applying vitamin D3 supplementation to prevent and treat pathological conditions.

Mechanistic approaching study in COVID-19 patients treated with high doses of vitamin D

Aim: To evaluate angiotensin II (Ang II) and Ang-(1-7) levels and the cytokine profile in patients hospitalized with mild coronavirus disease 2019 (COVID-19) and contrast them with patients with identical clinical conditions but treated with high doses of vitamin D (vitD). Methods: From the 218 patients recruited (ClinicalTrials.gov NCT04411446), 16 participated in this sub-study and were randomized to a single oral dose of 500,000 IU vitD (n = 10) or placebo (n = 6). Plasmatic Ang II and Ang-(1-7) levels were determined by radioimmunoassay and interleukins (ILs) 1, 6, 8, and 10 and tumor necrosis factor alpha (TNF-α) by enzyme-linked immunosorbent assay before and after treatment. Parallel, serum 25-hydroxyvitamin D3 (25-OH vitD) concentrations as vitD status was measured by a chemiluminescence immunoassay. Results: A trend towards an increase in Ang-(1-7) and a decrease in Ang II levels were observed in placebo- and vitD-treated COVID-19 patients compared to baseline values. There was no difference in Ang II and Ang-(1-7) levels between placebo- and vitD-treated COVID-19 patients. Similar results were obtained with ILs profile. COVID-19 patients showed an increase in the protective component of the RAS which was not improved by vitD treatment. Conclusions: VitD did not improve RAS disbalance in COVID-19. Notwithstanding, the authors visualize that acute treatment with high doses of vitD may show a trend to a decline in inflammatory ILs and an increase in protective markers. Finally, the authors would like to highlight the limitations of this preliminary study, namely the small number of patients and the use of a large single bolus dose of vitD rather than lower daily doses for extended periods with prolonged follow-up times. All these factors need special consideration in the designs of new vitD supplementation trials. All these factors need special consideration in the designs of new vitD supplementation trials (ClinicalTrials.gov identifier: NCT04411446).

Altered Expression of Antimicrobial Peptides in the Upper Gastrointestinal Tract of Patients with Diabetes Mellitus.

Antimicrobial peptides (AMP) are essential components of innate immunity with a broad range of antimicrobial activities against bacteria, viruses, and fungi. The aim of this study was to investigate AMP expression in the upper gastrointestinal tract in normal and pathological metabolic states in humans. Furthermore, we examined the correlation between vitamin D levels and AMP expression in the same cohort. Serum concentrations of 25-hydroxyvitamin D3 were measured, and mRNA expression of β-defensins HBD-1, -2, -3, -4, α-defensins HD-5 and -6 and cathelicidin in the upper gastrointestinal tract epithelia were determined by quantitative RT-PCR in 31 individuals (10 with type 2 diabetes, 10 with insulin resistance, and 11 healthy controls). The majority of the cohort showed low vitamin D concentrations, which were negatively correlated with mRNA expression levels of HBD-3 in corpus mucosa. HBD-1 and HBD-3 mRNA were expressed in corpus mucosa, with the former significantly decreased in patients with diabetes. Hence, we conclude that type 2 diabetes is associated with reduced AMP expression in the upper gastrointestinal tract, which might contribute towards epithelial barrier dysfunction and increased bacterial translocation in these patients.

Vitamin D deficiency and severity of pneumonia in Indonesian children.

To determine the prevalence of vitamin D deficiency in Indonesian children hospitalized with pneumonia and evaluate the association between vitamin D status and severity of pneumonia. A hospital-based cross-sectional study was conducted from February 2016 to July 2017 in two district hospitals in Yogyakarta province, Indonesia. Infants and young children aged 2-59 months hospitalized with pneumonia were recruited. Serum blood samples were collected on admission and analyzed for total serum 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 concentrations using liquid chromatography-tandem mass spectrometry. Vitamin D deficiency was defined as a level of serum vitamin D <50 nmol/L. The association between vitamin D deficiency and severity of hospitalized pneumonia according to WHO criteria, including the presence of danger signs, hypoxemia (SpO2 in air below 90%), duration of hospitalization, and admission to Intensive Care Unit (ICU), was analyzed using logistic regression. 133 children with WHO-defined pneumonia were enrolled in the study and 127 (96%) had their vitamin D status determined. The mean vitamin D concentration was 67 (± 24 SD) nmol/L and 19% of participants were vitamin D deficient. Age younger than 6 months was associated with prolonged hospitalization (> 5 days) and low birth weight and poor nutritional status on admission were risk factors for hypoxemia. However, vitamin D status was not associated with the presence of danger signs, duration of hospitalization, or hypoxemia. One in every five children hospitalized with pneumonia was vitamin D deficient. Vitamin D status was not associated with the severity of pneumonia.

Relationship between serum vitamin D3 concentration and anaemia in patients with chronic kidney disease in China.

ObjectiveIn the present study, we aimed to investigate the relationship between serum vitamin D3 concentration and anaemia in patients with chronic kidney disease (CKD) in China, to assist understanding of the effects of vitamin D treatment in such patients.MethodsA total of 225 patients with CKD were enrolled and a range of laboratory parameters were measured. The participants were allocated to three groups, according to their serum 25-hydroxyvitamin D3 concentration: a severe deficiency group, a deficiency group, and a sufficiency group. The prevalences of anaemia in the three groups were assessed, and the factors associated with anaemia in patients with CKD were analysed using logistic regression.ResultsThe prevalences of anaemia were 79.5% in the severe deficiency group, 63.5% in the deficiency group, and 48.0% in the sufficiency group. The prevalence of anaemia gradually increased with the severity of vitamin D3 deficiency. The prevalences of anaemia in participants with stages 1 to 5 CKD were 21.1%, 30.4%, 39.5%, 78.7%, and 94.6%, respectively.ConclusionVitamin D3 deficiency may increase the risk of anaemia in patients with CKD.

Higher Serum Vitamin D Concentrations Are Longitudinally Associated with Better Global Quality of Life and Less Fatigue in Colorectal Cancer Survivors up to 2 Years after Treatment.

Vitamin D status may be an important determinant of health-related quality of life of colorectal cancer survivors. The current study investigated longitudinal associations between serum 25-hydroxyvitamin D3 (25OHD3) concentrations and quality of life in stage I-III colorectal cancer survivors up to 2 years after treatment. Patients with colorectal cancer (n = 261) were included upon diagnosis. Home visits (including blood sampling) were performed at diagnosis and at 6 weeks, 6 months, 1 year, and 2 years after treatment. Serum 25OHD3 concentrations were measured using LC/MS-MS and adjusted for season. Validated questionnaires were used to assess global quality of life and cognitive functioning (EORTC-QLQ-C30), fatigue (EORTC-QLQ-C30 and Checklist Individual Strength, CIS), and depression and anxiety (Hospital Anxiety and Depression Scale). Statistical analyses were performed using linear mixed models and adjusted for sex, age, time since diagnosis, therapy, comorbidities, physical activity, and body mass index. At diagnosis, 45% of patients were vitamin D deficient (<50 nmol/L). After treatment, 25OHD3 concentrations increased on average with 3.1 nmol/L every 6 months. In confounder-adjusted models, 20 nmol/L increments in 25OHD3 were longitudinally associated with increased global quality of life [β 2.9; 95% confidence interval (CI), 1.5-4.3] and reduced fatigue (EORTC-QLQ-C30 subscale: β -3.5; 95% CI, -5.3 to -1.8 and CIS: β -2.8; 95% CI, -4.7 to -0.9). Observed associations were present both within and between individuals over time. Higher concentrations of 25OHD3 were longitudinally associated with better global quality of life and less fatigue in colorectal cancer survivors. This study suggests that higher 25OHD3 concentrations may be beneficial for colorectal cancer survivors. Future intervention studies are needed to corroborate these findings.

The effect of an oral sodium phosphate load on parathyroid hormone and fibroblast growth factor 23 secretion in normo- and hypercalciuric stone-forming patients.

Abnormalities of parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) secretion may cause calcium-phosphate (Ca-P) metabolism disorders in nephrolithiasis. Post-phosphate-load alterations in serum Ca, P and PTH, phosphaturia and calciuria enable monitoring hormonal regulation of Ca-P homeostasis. Our study aimed to determine differences in: 1.selected Ca-P metabolism parameters between healthy and kidney-stone-forming individuals, 2.PTH and FGF23 secretion induced by sodium-phosphate-load(NaP-load) in patients with/without hypercalciuria, 3.secretion of Ca-P related hormones in patients with low and normal/high serum concentrations of 25-hydroxyvitamin D3 (25OHD3). Sodium phosphates NaH2PO4/Na2HPO4-100mmol were administered orally for five days in 19 hypercalciuric [urinary Ca(U-Ca) 6.5±1.7mmol/d]-HSF, 35 normocalciuric (2.5±1mmol/d)-NSF stone-forming patients and 19 controls (U-Ca 2.5±1.4mmol/d)-CG. On days 1 and 5 PTH-,FGF23-,Ca-,P were determined before and after NaP-load. The areas under PTH, FGF23 curves (AUC) were calculated. U-Ca, urinary phosphate (U-P) and sodium (U-Na) were also determined. Following NaP-load, patients and controls exhibited expected alterations in Ca-P homeostasis. Despite changes in phosphate and PTH, no differences in FGF23 concentrations were observed. Patients differed from controls in having higher AUCPTH, calciuria and natriuresis, taking longer for PTH and P to normalize and lack of correlation between AUCPTH and phosphaturia. Post-NaP-load hypocalciuric effect of PTH secretion in NSF was less pronounced than in CG. In the HSFs, the hypocalciuric effect was more pronounced than in NSFs, but insufficient to correct hypercalciuria. In all stone-formers with low 25OHD3 concentrations, the AUCFGF23 was significantly increased on first (1215±605vs766±315 p=0.0457) and fifth days (1211±641vs777±299 p=0.041) of NaP-load, compared to normal/high 25OHD3-patients. Hypercalciuric patients with low 25OHD3 concentrations had greater AUCPTH5 than those with normal/high 25OHD3 (1005±401vs835±220 p=0.0341). Compared to controls, kidney-stone-forming patients exhibited enhanced PTH secretion after NaP-load. The HSFs showed a more pronounced hypocalciuric effect than NSFs, but insufficient to correct hypercalciuria. In hypercalciuric stone-formers with low 25OHD3, FGF23 engagement in hyperphosphatemia reduction increased.

Vitamin D Status in Women with Uterine Fibroids: A Cross-sectional Study

BACKGROUND: Uterine fibroids (UFs) affect women of reproductive age and lead to major morbidity in premenopausal women. Identifying modifiable risk factors could help develop new UF prevention and treatment strategies.&#x0D; OBJECTIVES: The purpose of this research was to investigate the relationship between serum Vitamin D3 levels and UF in women seeking gynecological services.&#x0D; METHODS: This case–control design was conducted in September 2018 at the outpatient gynecology clinic of Shahid Beheshti University of Medical Sciences, Tehran, Iran. Cases had at least one ultrasound confirmed fibroid lesion with an average volume of 2 cm or greater. The outpatient clinic has enrolled a control group of patients without UF, based on transvaginal ultrasonography or any other gynecologic pathology. Radioimmunoassay techniques were applied to measure serum Vitamin D [25(OH) D3] levels.&#x0D; RESULTS: A total of 148 patients met inclusion criteria, 71 women were had at least one UF and the remaining 77 participants showed normal, UF-free uterine structure. The mean serum concentration of 25-hydroxyvitamin D3 was lower in UF patients (21.37 ± 7.49 ng/mL) than without (24.62 ± 9.21 ng/mL) (p = 0.02). A modified odds ratio derived from a backward logistic regression model for 25-hydroxyvitamin D3 that included positive family history, age, body mass index, bleeding volume, physical activity, sun exposure, and history of abortion was 0.92 (95% CI, 0.88–0.98) (P = 0.02).&#x0D; CONCLUSION: For women with UFs, the serum level of 25-hydroxyvitamin D3 was significantly lower than in controls. Vitamin D3 deficiency is a potential risk factor for UFs to occur.

A21 VITAMIN D DEFICIENCY AND ITS ASSOCIATION WITH CLINICAL OUTCOMES IN PRIMARY SCLEROSING CHOLANGITIS

Abstract Background Primary sclerosing cholangitis (PSC) is a progressive cholestatic disease involving chronic inflammation and fibrosis of intra- and extra-hepatic ducts. Vitamin D is a secosteroid implicated in anti-inflammatory and anti-fibrotic pathways, and its deficiency has been associated with worse outcomes in chronic liver disease. Vitamin D status may also influence the course of PSC but studies evaluating this link are scarce. Aims To determine the association of vitamin D deficiency with the development of cirrhosis, mortality, and need for liver transplantation in patients with PSC. Methods Ninety-four patients with the diagnosis of PSC were evaluated and followed by the autoimmune liver disease clinic at the University of Alberta, Edmonton, Canada. Clinical data were recovered from medical charts. Vitamin D status was defined by the serum concentration of 25-hydroxyvitamin D3. Patients with levels &amp;lt;50 nmol/L (10 ng/ml) were defined as deficient. Univariate and multivariate analyses were constructed using the Cox proportional hazards regression models. Event-free survival was defined as time from vitamin D assessment to the time of liver transplant or death. Results Mean age at PSC diagnosis was 32±14 years, with 67% of patients being male. The mean vitamin D level was 69±33 nmol/L (range, 4–163 nmol/L) and 26 patients (28%) had vitamin D deficiency (&amp;lt;50 nmol/L). Among 85 patients without cirrhosis at diagnosis, 43 patients (51%) developed cirrhosis. By univariate Cox analysis, serum ALP, albumin, bilirubin and vitamin D deficiency were predictors of cirrhosis development. Vitamin D deficiency was independently associated with higher risk of developing cirrhosis (HR 2.11, 95% CI 1.002–4.44, P=0.049) after adjusting for other predictors. Median time to develop cirrhosis was shorter in patients with vitamin D deficiency (6.8 years; 95% CI, 1.7–11.8) compared to those without (10.8 years; 95% CI, 9.2 -12.4; P=0.007). Over a median follow-up period of 5.6 years, adverse outcomes (liver transplant or death) were observed in 34 patients (36%). Serum levels of albumin, ALP, bilirubin, INR, platelet count, ascites, variceal bleeding and vitamin D deficiency were associated with adverse outcomes in univariate analysis. Vitamin D deficiency was independently associated with higher risk of adverse endpoints (HR 2.87, 95% CI, 1.16–7.12, P=0.02) after adjusting for confounding factors. Event-free survival was shorter in the patients with vitamin D deficiency compared to those without deficiency (7.1 years; 95% CI, 2.4–11.9 vs. 11.4 years; 95% CI, 8.9–13.9, P=0.03, Figure 1). Conclusions Vitamin D deficiency was frequent in patients with PSC and was associated with higher risk of progression to cirrhosis, as well as decreased time to death and liver transplantation. The possibility of improving outcomes in PSC by vitamin D supplementation awaits further investigation. Funding Agencies Food and Health Innovation Initiative (Vitamin Fund), University of Alberta

Five salmon dinners per week were not sufficient to prevent the reduction in serum vitamin D in autumn at 60° north latitude: a randomised trial.

Low serum concentrations of several vitamins have been linked to increased risk of diseases including insulin resistance and type 2 diabetes (T2D). Fish is a good source of several vitamins, and the prevalence of T2D is low in populations with high fish intake. The aim of the present study was to investigate the effects of high fish intake on vitamins in serum from adults in autumn in South-Western Norway at 60° north latitude. In this randomised clinical trial, sixty-three healthy participants with overweight/obesity consumed 750 g/week of either cod (n 22) or salmon (n 22) as five weekly dinners or were instructed to continue their normal eating habits but avoid fish intake (Control group, n 19) for 8 weeks. The estimated vitamin D intake was significantly increased in the Salmon group when compared with the Cod group (P = 6·3 × 10-4) and with the Control group (P = 3·5 × 10-6), with no differences between groups for estimated intake of vitamins A, B1, B2, B3, B6, B9, C and E. Serum 25-hydroxyvitamin D3 concentration was decreased in all groups after 8 weeks; however, the reduction in the Salmon group was significantly smaller compared with the Cod group (P = 0·013) and the Control group (P = 0·0060). Cod and salmon intake did not affect serum concentrations of the other measured vitamins. The findings suggest that 750 g/week of salmon was not sufficient to prevent a decrease in serum 25-hydroxyvitamin D3 in autumn in South-Western Norway in adults with overweight/obesity.

Quality specifications and their daily application to evaluate the accuracy of reference measurements for serum concentrations of 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2

BackgroundReference measurement procedures (RMP) have rigorous accuracy specifications. For total 25-hydroxyvitamin D, 25(OH)D, bias ≤1.7% and CV ≤5% are recommended. These quality specifications are impractical for minor analytes, such as 25(OH)D2. Furthermore, documentation on RMP quality performance specifications for the individual 25(OH)D metabolites and their daily application are missing. MethodsTo assess accuracy, we used zeta-scores. Daily, 5–10 specimens (duplicate) and 3 reference materials (singleton or duplicate) were measured for 25(OH)D3 and 25(OH)D2 using JCTLM-accepted LC-MS/MS RMPs. Protocols were repeated on 3–4 occasions to generate campaign results. We used separate zeta-score acceptability criteria for daily (≤|2|) and campaign (≤|1|) evaluations. Allowable imprecision was determined experimentally. ResultsAcross 7 campaigns, unacceptable daily zeta-scores required repeating 2 runs for 25(OH)D3 and 5 runs for 25(OH)D2. Hence, the zeta-scores of acceptable reference material results indicated high accuracy. The allowable imprecision for the RMPs was ≤5% (daily) and ≤ 3% (campaign) for 25(OH)D3 and ≤ 7% (daily) and ≤ 4% (campaign) for 25(OH)D2, respectively. ConclusionsUsing zeta-scores and experimentally derived imprecision, we developed a straightforward approach to assess the acceptability of individual 25(OH)D reference measurements, providing also much-needed practical accuracy specifications for 25(OH)D2.

Serum concentrations of interleukin 18 and 25-hydroxyvitamin D3 correlate with depression severity in men with psoriasis.

ObjectivePsoriasis and depression may have common mechanisms, such as systemic inflammation, dysfunction of the hypothalamic-pituitary-adrenal axis, and vitamin D3 deficiency. Among men with psoriasis, this study examined whether depression severity was associated with serum concentrations of different metabolic and inflammatory markers.MethodsThe study included 85 men with psoriasis (mean age ± standard deviation [SD], 47 ± 14 years) and 65 men without psoriasis (mean age ± SD, 44 ± 13 years). In both groups, we measured the body mass index; blood pressure; and serum concentrations of lipids, uric acid, lipase, interleukins 6 and 18, cortisol, and 25-hydroxyvitamin D3. All participants completed the Beck Depression Inventory. Other variables analyzed included psoriasis duration, the Psoriasis Area Severity Index, and the percentage of body surface area affected by psoriatic lesions.ResultsCompared with controls, patients with psoriasis had significantly greater depression severity, higher body mass indices, and higher serum concentrations of total cholesterol and interleukins 6 and 18; moreover, they had significantly lower serum 25-hydroxyvitamin D3 concentrations. In patients with psoriasis, depression severity correlated positively with psoriasis duration, the Psoriasis Area Severity Index, the percentage of body surface area affected by psoriatic lesions, and interleukin-18 concentration. In patients with psoriasis, depression severity correlated negatively with 25-hydroxyvitamin D3 concentration, but it did not correlate significantly with the serum concentrations of interleukin 6 and cortisol.ConclusionsHigh concentrations of interleukin 18 and low concentrations of 25-hydroxyvitamin D3 may be associated with depression severity in men with psoriasis. Thus, further studies should examine whether effective anti-inflammatory treatments or vitamin D3 supplementation can improve depression outcomes in these patients.

Severe Vitamin D3 Deficiency in the Majority of Patients with Diabetic Foot Ulcers.

Diabetic foot ulcers are a severe complication in patients with diabetes mellitus. Vitamin D is associated with impaired β-cell function and insulin resistance, and is necessary for wound healing and bone metabolism. We measured the serum concentrations of 25-hydroxyvitamin D3 in 104 patients (63 inpatients, 41 outpatients) with diabetic foot ulcers and compared them to 99 healthy humans (control) and 103 patients with diabetes mellitus type 2 without diabetic foot ulcers. Calcium, creatinine, and parathyroid hormone were measured in patients with diabetic foot ulcers. The data were analysed together with glycosylated hemoglobin A1c and the severity of diabetic foot lesions according to the Armstrong classification. Levels of 25-hydroxyvitamin D3 were lower (11.8±11.3 ng/ml, p<0.001) in patients with diabetic foot ulcers (mean age 70±12 years) than in the control group (27.2±12.2 ng/ml). No difference was found between in- and outpatients. Fifty-eight (55.8%) of patients with diabetic foot ulcers had a severe 25-hydroxyvitamin D3 deficiency with levels below 10 ng/ml. Only 12% of the patients had 25-hydroxyvitamin D3 levels above 20 ng/ml. Secondary hyperparathyroidism was found in 27.9% of patients and 11.5% of the patients were hypocalcemic. There was a negative correlation (r=-0.241) (p<00.1) between Armstrong classification and 25-hydroxyvitamin D3 status. In conclusion, patients with diabetic foot syndrome are at high risk of 25-hydroxyvitamin D3 deficiency. Thus, any patient with diabetic foot syndrome should undergo 25-hydroxyvitamin D3 measurement and supplementation, if values are found to be decreased.

25-Hydroxy vitamin D3 serum concentration in dogs with acute polyradiculoneuritis compared to matched controls.

To determine if dogs with acute polyradiculoneuritis have lower serum 25-hydroxy vitamin D3 concentration compared to a control group of dogs with idiopathic epilepsy. Retrospective case-control study of 21 dogs with acute canine polyradiculoneuritis and 21 control dogs with idiopathic epilepsy matched for year and season of presentation from a referral hospital population in the UK. Serum concentration of 25-hydroxy vitamin D3 was compared between groups using Student's t-test. Dogs with acute canine polyradiculoneuritis had significantly lower (P=0·033) serum 25-hydroxy vitamin D3 concentration (87·1 nmol/L ±55·4 nmol/L) compared to a control group with idiopathic epilepsy (113 nmol/L ±66·3 nmol/L). The cause and clinical significance of the altered vitamin D status in dogs with acute polyradiculoneuritis are not clear and require further investigation. Our findings pave the way for improved understanding of acute canine polyradiculoneuritis and, potentially, improved clinical management, if a causal role for 25-hydroxy vitamin D3 is defined.

The association between serum 25-hydroxyvitamin D3 concentration and serum lipids in the rural population of China

BackgroundVitamin D deficiency is implicated in some diseases, including cardiovascular. Few studies have assessed the correlation between 25-hydroxyvitamin D3 [25(OH) D3] and serum lipids. In this study, we explored the correlation between serum 25(OH) D3 concentrations and serum lipids with a typical sample of the rural population in China.MethodsFace-to-face research was used to gather some basic information. Fasting serum concentrations of 25-(OH) D3, total cholesterol (TC), triglyceride (TG), HDL cholesterol (HDL-C) and, LDL cholesterol (LDL-C) tested in the laboratory.ResultsThe mean of serum 25(OH) D3 level was 28.71 ± 29.29 ng/mL. The results showed that the dyslipidemia was strongly associated with gender (P = 0.031), drinking (P = 0.043), high-fat diet intake (P = 0.017), HDL-C (P<0), TG (P<0), body mass index (BMI) (P<0) and serum 25(OH)D3 levels (P = 0.002). There was a positive correlation between serum 25(OH)D3 and HDL-C (P<0) in all groups. The relationship between 25(OH) D3 and LDL-C (P = 0.024) was discovered only in normal lipid group. The multivariable adjusted odds ratio (95%CI) of hypoalphalipoproteinemia/HDL and dyslipidemia by comparing the sufficiency vs. the deficiency serum 25-(OH) D3 level were 0.31 (0.192, 0.499) (P = 0.001) and 0.52 (0.36, 0.73) (P = 0.005), respectively.ConclusionsSerum 25(OH) D3 concentrations were associated with the serum lipids level and the association was different in normal serum lipid group and dyslipidemia group. With the increase of serum 25(OH) D3 levels, the incidence of dyslipidemia decreased.

Development of a highly sensitive in vitro system to detect and discriminate between vitamin D receptor agonists and antagonists based on split-luciferase technique

Split-luciferase techniques are widely used to detect protein–protein interaction and bioactive small molecules including some hormones and vitamins. Previously, we successfully expressed chimeric proteins of luciferase and the ligand binding domain (LBD) of the vitamin D receptor (VDR), LucC-LBD-LucN in COS-7 cells. The LucC-LBD-LucN biosensor was named split-luciferase vitamin D biosensor (SLDB). This biosensor can detect and discriminate between VDR agonists and antagonists in mammalian cells. In this study, we established an in vitro screening system for VDR ligands using the SLDB proteins expressed in Escherichia coli (E. coli) cells. Our in vitro screening system using cell lysate of recombinant E. coli cells could be completed within 30min, and its activity was unchanged after 10 freeze-thaw cycles. This highly sensitive and convenient system would be quite useful to screen VDR ligands with therapeutic potential for various bone-related diseases, age-related cognitive disorders, cancer, and immune disorders. In addition, our system might be applicable to diagnostic measurement of serum concentrations of 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3.

Cholecalciferol supplementation of heifer diets increases beef vitamin D concentration and improves beef tenderness

This study investigated the effects of cholecalciferol (vitamin D₃) supplementation on beef vitamin D activity, beef tenderness and sensory attributes. Thirty heifers were randomly allocated to one of three finishing dietary treatments [(T1) basal diet+0IU vitamin D₃; (T2) basal diet+2000IU vitamin D₃; and (T3) basal diet+4000IU vitamin D₃] for a 30day period pre-slaughter. Vitamin D₃ supplementation linearly increased serum 25-hydroxyvitamin D₃ (25-OH-D3) concentrations (R2=0.48), Longissimus thoracis (LT) total vitamin D activity (R2=0.78) as well as individually vitamin D₃ (R2=0.84) and 25-OH-D₃ (R2=0.75). The highest vitamin D₃ inclusion diet (T3) had a 42% increase (P<0.001) in LT vitamin D activity compared to the intermediate diet (T2) and a 145% increase over the lowest level diet (T1). Vitamin D₃ supplementation decreased LT shear (P<0.05) force values after 14days chilling. Sensory parameters were not affected (P>0.05). In conclusion, through short-term vitamin D₃ supplementation of cattle diets, beef vitamin D activity can successfully be enhanced.

Interrelationship between serum 25-hydroxyvitamin D3 concentration and lipid profiles in premenopausal Indian women.

Context:Vitamin D deficiency is prevalent worldwide, and observational studies have associated it with an atherogenic lipid profile.Aim:To determine the interrelationship between Vitamin D and lipid profile in apparently healthy premenopausal Indian women, considering confounding factors such as lifestyle that independently influence lipids.Setting and Design:Cross-sectional study.Subjects and Methods:One hundred and twenty healthy premenopausal women (20–45 year) were recruited from Gujarat, India. Data were collected on anthropometry, physical activity, sunlight exposure, and diet. Fasting blood samples were collected for the measurement of serum 25-hydroxyvitamin D3 (25[OH]D), parathyroid hormone, and lipid profile.Statistical Analysis:Pearson's correlation coefficient was used to derive correlation between serum 25[OH]D concentrations and serum lipids.Results:Ninety-three percent women showed Vitamin D deficiency (serum 25[OH]D < 20 ng/ml). Serum 25(OH)D concentrations showed significant inverse correlation with total cholesterol (TC) (r = −0.202, P = 0.027), triglycerides (TG) (r = −0.284, P = 0.002), and low-density lipoprotein-cholesterol (LDL-C) (r = −0.184, P = 0.044) and positive correlation with high-density lipoprotein-cholesterol (HDL-C) (r = 0.250, P = 0.006). On dichotomizing the population according to median 25(OH)D concentration (11.1 ng/dl), no significant differences were observed between the groups for anthropometry, sunlight exposure, and lifestyle. Serum lipid profiles were significantly different, above median serum 25(OH)D concentration group showed favorable serum lipids (TC: 179.3 ± 30 vs. 191.8 ± 31.7 mg/dl; TG: 140 ± 39.1 vs. 165.5 ± 53.4 mg/dl; LDL-C: 100 ± 30.2 vs. 112 ± 32 mg/dl; HDL-C: 53 ± 14 vs. 47.6 ± 9.3 mg/dl)(P < 0.05).Conclusions:This study demonstrates that association of 25(OH)D concentrations with lipid profile even after considering lifestyle factors which independently influence lipids. Intervention trials would be required to prove this association to be causation.