Can paricalcitol increase the effectiveness of n-acetylcysteine in contrast induced acute kidney prophylaxis in rats? A biochemical and histopathological study / ¿Puede el paricalcitol aumentar la eficacia de la n-acetilcisteína en la profilaxis renal aguda inducida por contraste en ratas? Un estudio bioquímico e histopatológico

SUMMARY: N-Acetylcysteine (NAC) is used for contrast induced acut kidney injury (CI-AKI) prophylaxis because of its antioxidant effects. Paricalcitol, which has reno-protective effects, is likely to provide a more effective prophylaxis when added to NAC treatment. The study was designed based on this hypothesis. The study was organised to include 4 groups each consisting of 7 rats. Group 1 was the control group, and Group 2 included rats with CI-AKI. Rats in Group 3 were administered NAC at a dose of 100 mg/kg via oral gavage once a day for 5 days. Rats in group 4 were administered paricalcitol at a dose of 0.4 mcg/kg once a day for 5 days in addition to NAC. CI-AKI was induced after the treatments in both groups. The study was terminated on the sixth day. Samples were collected from the rats' sera and kidney tissues to study oxidant and antioxidant parameters; kidney function tests were also studied. There were significant differences between the contrast nephropathy group (Group 2) and NAC and NAC+paricalcitol groups with respect to serum urea and creatinine levels. When the same groups were compared regarding oxidant (TOS-MDA) and antioxidant (TAC-Paraoxonase) parameters, we observed that the oxidant parameters increased in serum and kidney tissue samples with NAC use, and that effect was strengthened by the addition of paricalcitol to NAC treatment. However, despite increased antioxidant effectiveness, we observed no decrease in urea and creatinine levels when paricalcitol was added for CI-AKI in rats. There was no significant difference between Group 3 and Group 4. Paricalcitol provides a more potent antioxidant effect in both serum and kidney tissue samples when added to NAC treatment in rats with CI-AKI. Despite increased antioxidant parameters, however, paricalcitol does not provide a significant decrease in urea and creatinine levels.

RESUMEN: Debido a sus efectos atioxidantes la N- acetilcisteína (NAC) se usa para la profilaxis de la lesión renal aguda inducida por contraste (CI-AKI). Es probable que el paricalcitol, que tiene efectos renoprotectores, proporcione una profilaxis más eficaz cuando se agrega al tratamiento con NAC. En base a esta hipótesis el estudio fue diseñado para incluir cuatro grupos cada uno compuesto por siete ratas. El grupo 1 fue el grupo control y el grupo 2 incluyó ratas con CI-AKI. A las ratas del Grupo 3 se les administró NAC con una dosis de 100 mg/kg por sonda oral una vez al día, durante 5 días. A las ratas del grupo 4 se les administró paricalcitol a una dosis de 0,4 mcg/kg una vez al día durante 5 días, además de NAC. Se indujo CI-AKI después de los tratamientos en ambos grupos. El estudio finalizó el sexto día. Se recolectaron muestras de suero y tejidos renales de ratas para estudiar los parámetros oxidantes y antioxidantes; También se estudiaron las pruebas de función renal. Hubo diferencias significativas entre el grupo de nefropatía por contraste (Grupo 2) y los grupos NAC y NAC+paricalcitol con respecto a los niveles séricos de urea y creatinina. Cuando se compararon los mismos grupos con respecto a los parámetros oxidantes (TOS-MDA) y antioxidantes (TAC-Paraoxonase), observamos que los parámetros oxidantes aumentaron en muestras de suero y tejido renal con el uso de NAC, y ese efecto se vio reforzado por la adición de paricalcitol a tratamiento NAC. Sin embargo, a pesar de una mayor eficacia antioxidante, no observamos una disminución en los niveles de urea y creatinina cuando se agregó paricalcitol para CI-AKI en ratas. No hubo diferencias significativas entre el Grupo 3 y el Grupo 4. El paricalcitol proporciona un efecto antioxidante más potente tanto en muestras de suero como de tejido renal cuando se agrega al tratamiento con NAC en ratas con CI-AKI. Sin embargo, a pesar del aumento de los parámetros antioxidantes, el paricalcitol no proporciona una disminución sig- nificativa en los niveles de urea y creatinina.

Preclinical Therapy with Vitamin D3 in Experimental Encephalomyelitis: Efficacy and Comparison with Paricalcitol.

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS). MS and its animal model called experimental autoimmune encephalomyelitis (EAE) immunopathogenesis involve a plethora of immune cells whose activation releases a variety of proinflammatory mediators and free radicals. Vitamin D3 (VitD) is endowed with immunomodulatory and antioxidant properties that we demonstrated to control EAE development. However, this protective effect triggered hypercalcemia. As such, we compared the therapeutic potential of VitD and paricalcitol (Pari), which is a non-hypercalcemic vitamin D analog, to control EAE. From the seventh day on after EAE induction, mice were injected with VitD or Pari every other day. VitD, but not Pari, displayed downmodulatory ability being able to reduce the recruitment of inflammatory cells, the mRNA expression of inflammatory parameters, and demyelination at the CNS. Lower production of proinflammatory cytokines by lymph node-derived cells and IL-17 by gut explants, and reduced intestinal inflammation were detected in the EAE/VitD group compared to the EAE untreated or Pari groups. Dendritic cells (DCs) differentiated in the presence of VitD developed a more tolerogenic phenotype than in the presence of Pari. These findings suggest that VitD, but not Pari, has the potential to be used as a preventive therapy to control MS severity.

Effectiveness of intramuscular ergocalciferol treatment in a patient with osteomalacia and insufficiency fractures due to severe vitamin D deficiency after bariatric surgery.

Vitamin D (vitD) deficiency and bone loss may occur after bariatric surgery and hence, supplementation with high oral doses of vitD may be required. Alternatively, intramuscular depot ergocalciferol, which slowly releases vitD and bypasses the gastrointestinal tract, could be administrated. We present a case of severe vitD deficiency-osteomalacia after gastric bypass operation for morbid obesity, treated with ergocalciferol intramuscularly. A 45-year-old woman was presented with hip pain and muscle weakness, which led ultimately to immobilization in a wheelchair. Fifteen years ago, she underwent roux-en-Y gastric by-pass for morbid obesity. Occasionally, she was treated with multivitamin supplements. On admission, iron deficiency anaemia, vitD deficiency (25OHD: 3.7 ng/ml) and secondary hyperparathyroidism were revealed. Bone turnover markers (BTM) were elevated. Radiological evaluation demonstrated insufficiency fractures on the pubic and left femur and reduced BMD. Osteomalacia due to vitD deficiency and calcium malabsorption were diagnosed. Calcium citrate 500 mg qid and intramuscular ergocalciferol 600,000 IU every 20 days were initiated. One month later, musculoskeletal pain and weakness were resolved and the patient was mobilized. Few months later, vitD, BTM and BMD showed substantial improvement. Intramuscular ergocalciferol administration can improve the clinical and biochemical status and thus, is suggested to prevent and/or treat osteomalacia in such patients.

[Vitamin D deficiency in Spanish population. Importance of egg on nutritional improvement]. / Deficiencia en vitamina D de la población española. Importancia del huevo en la mejora nutricional.

INTRODUCTION: Vitamin D is an essential nutrient whose deficiency has been associated with the risk of various chronic diseases such as osteoporosis, hypertension, cardiovascular disease, diabetes, some types of cancer and even overweight and obesity. Although vitamin D can be synthesized at the skin from exposure to sunlight, this source is not always sufficient to meet the needs. For example, the use of sunscreen or the low exposition to the sunlight limits the syntheses. In fact, studies have found that at least half of the Spanish population has vitamin D deficits. Therefore, the dietary contribution is fundamental. Although there are different foods fortified in this vitamin, few products are natural source of it, as fatty fish and eggs. However, according to different studies carried out in the Spanish population, there is a low consumption of this food group. In this way, it would be advisable to promote egg consumption among the population, since this food, in addition to having many nutrients, contains a high amount of vitamin D, which contributes to avoid the appearance of deficiencies and the consequences health consequences that this implies.

INTRODUCCIÓN: La vitamina D es un nutriente esencial cuya deficiencia se ha asociado con el riesgo de aparición de diversas enfermedades crónicas, como la osteoporosis, la hipertensión arterial, la enfermedad cardiovascular, la diabetes, algunos tipos de cáncer e incluso el padecimiento de sobrepeso y obesidad. A pesar de que la vitamina D puede sintetizarse a nivel cutáneo a partir de la exposición a la luz solar, esta fuente no es siempre suficiente para cubrir las necesidades debido al uso de cremas de protección solar y a la baja exposición que se produce durante el invierno, o, como en el caso de las personas enfermas, que salen poco a la calle o se exponen poco a la luz del sol. De hecho, estudios han constatado que al menos la mitad de la población española presenta déficit de vitamina D. Por ello, el aporte dietético es fundamental. Aunque existen diferentes alimentos fortificados con esta vitamina, son pocos los productos que son una fuente natural, entre los que se encuentran los pescados grasos y los huevos. Sin embargo, de acuerdo con diferentes estudios realizados en la población española, existe un bajo consumo de este último grupo de alimentos. De esta manera, sería recomendable fomentar el consumo de huevo entre la población, ya que este alimento, además de tener numerosos nutrientes, contiene una cantidad elevada de vitamina D, lo que contribuye a evitar la aparición de deficiencias y las consecuencias negativas para la salud que ello implica.

Association between vitamin D supplementation and mortality: systematic review and meta-analysis.

OBJECTIVE: To investigate whether vitamin D supplementation is associated with lower mortality in adults. DESIGN: Systematic review and meta-analysis of randomised controlled trials. DATA SOURCES: Medline, Embase, and the Cochrane Central Register from their inception to 26 December 2018. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Randomised controlled trials comparing vitamin D supplementation with a placebo or no treatment for mortality were included. Independent data extraction was conducted and study quality assessed. A meta-analysis was carried out by using fixed effects and random effects models to calculate risk ratio of death in the group receiving vitamin D supplementation and the control group. MAIN OUTCOME MEASURES: All cause mortality. RESULTS: 52 trials with a total of 75 454 participants were identified. Vitamin D supplementation was not associated with all cause mortality (risk ratio 0.98, 95% confidence interval 0.95 to 1.02, I2=0%), cardiovascular mortality (0.98, 0.88 to 1.08, 0%), or non-cancer, non-cardiovascular mortality (1.05, 0.93 to 1.18, 0%). Vitamin D supplementation statistically significantly reduced the risk of cancer death (0.84, 0.74 to 0.95, 0%). In subgroup analyses, all cause mortality was significantly lower in trials with vitamin D3 supplementation than in trials with vitamin D2 supplementation (P for interaction=0.04); neither vitamin D3 nor vitamin D2 was associated with a statistically significant reduction in all cause mortality. CONCLUSIONS: Vitamin D supplementation alone was not associated with all cause mortality in adults compared with placebo or no treatment. Vitamin D supplementation reduced the risk of cancer death by 16%. Additional large clinical studies are needed to determine whether vitamin D3 supplementation is associated with lower all cause mortality. STUDY REGISTRATION: PROSPERO registration number CRD42018117823.

Cardioprotective effect of vitamin D2 on isoproterenol-induced myocardial infarction in diabetic rats.

OBJECTIVES: To assess the effect of vitamin D2 and to elucidate the underlying mechanisms on acute myocardial injury induced by isoproterenol (ISO) in diabetic rats. METHODS: Rats were divided into control rats, diabetic rats (DM), diabetic rats received ISO (DM-ISO), and diabetic rats pretreated with vitamin D2 and received ISO (DM-D2-ISO). RESULTS: Vitamin D2 pretreatment significantly decreased fasting glucose and myocardial malondialdehyde, associated with increased insulin, myocardial glutathione and superoxide dismutase in DM-D2-ISO versus DM-ISO. The serum triglycerides, total cholesterol, and LDL were significantly decreased, along with increased HDL and adiponectin. Poly-ADP ribose polymerase, cyclooxygenase-2, tumour necrosis factor alpha, interleukin-6, caspase-3, BAX, and p53 were significantly downregulated in myocardium of DM-D2-ISO versus DM-ISO. Histological studies showed diminished inflammatory cells infiltration in myocardium of DM-D2-ISO versus DM-ISO. CONCLUSION: Vitamin D2 ameliorates hyperglycaemia, dyslipidaemia, redox imbalance, inflammatory and apoptotic processes, protecting the myocardium of diabetic rats against acute myocardial infarction.

Effects of oral paricalcitol therapy on arterial stiffness and osteopontin in hypertensive patients with chronic kidney disease and secondary hyperparathyroidism.

BACKGROUND: Arterial stiffness is linked to the progression of atherosclerosis, while activation of vitamin D receptor exerts favorable cardiovascular effects in patients with renal insufficiency. In this study, we investigated the effects of oral treatment with paricalcitol, a potent vitamin D receptor activator, on arterial stiffness and osteopontin, a marker of atherosclerosis, in hypertensive patients with chronic kidney disease (CKD) and secondary hyperparathyroidism. METHODS: We followed up 29 treated hypertensive patients (mean age: 74.1 years, 19 men, office blood pressure = 132/85 mmHg) with CKD stages 3-5 (mean glomerular filtration rate [GFR] = 19.4 ml/min/1.73 m2) who were on therapy with oral paricalcitol for 1 year. The control group consisted of 10 age-, sex-, and GFR-matched hypertensive patients with secondary hyperparathyroidism. RESULTS: After 1 year of treatment with paricalcitol compared to baseline, there was no statistical difference in levels of GFR, office blood pressure, and osteopontin (p = NS for all), while carotid-femoral PWV was reduced from 11.8 ± 2.6 m/s to 11.2 ± 2.4 m/s (p < 0.05). The control group exhibited no significant changes in carotid-femoral PWV (p = NS). CONCLUSIONS: Treatment with oral paricalcitol in hypertensive subjects suffering from CKD stages 3-5 and secondary hyperparathyroidism is accompanied by amelioration of arterial stiffness as reflected by the reduction of carotid-femoral PWV.

Effects of Vitamin D2 (Ergocalciferol) and D3 (Cholecalciferol) on Atlantic Salmon (Salmo salar) Primary Macrophage Immune Response to Aeromonas salmonicida subsp. salmonicida Infection.

Vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are fat-soluble secosteroid hormones obtained from plant and animal sources, respectively. Fish incorporates vitamin D2 and D3 through the diet. In mammals, vitamin D forms are involved in mineral metabolism, cell growth, tissue differentiation, and antibacterial immune response. Vitamin D is an essential nutrient in aquafeeds for finfish. However, the influence of vitamin D on fish cell immunity has not yet been explored. Here, we examined the effects of vitamin D2 and vitamin D3 on Salmo salar primary macrophage immune response to A. salmonicida subspecies salmonicida infection under in vitro conditions. We determined that high concentrations of vitamin D2 (100,000 ng/ml) and D3 (10,000 ng/ml) affect the growth of A. salmonicida and decrease the viability of S. salar primary macrophages. In addition, we determined that primary macrophages pre-treated with a biologically relevant concentration of vitamin D3 for 24 h showed a decrease of A. salmonicida infection. In contrast, vitamin D2 did not influence the antibacterial activity of the S. salar macrophages infected with A. salmonicida. Vitamin D2 and D3 did not influence the expression of canonical genes related to innate immune response. On the other hand, we found that A. salmonicida up-regulated the expression of several canonical genes and suppressed the expression of leukocyte-derived chemotaxin 2 (lect-2) gene, involved in neutrophil recruitment. Primary macrophages pre-treated for 24 h with vitamin D3 counteracted this immune suppression and up-regulated the transcription of lect-2. Our results suggest that vitamin D3 affects A. salmonicida attachment to the S. salar primary macrophages, and as a consequence, the A. salmonicida invasion decreased. Moreover, our study shows that the positive effects of vitamin D3 on fish cell immunity seem to be related to the lect-2 innate immunity mechanisms. We did not identify positive effects of vitamin D2 on fish cell immunity. In conclusion, we determined that the inactive form of vitamin D3, cholecalciferol, induced anti-bacterial innate immunity pathways in Atlantic salmon primary macrophages, suggesting that its utilization as a component of a healthy aquafeed diet in Atlantic salmon could enhance the immune response against A. salmonicida.

A phase 1, open-label, dose escalation study of intravenous paricalcitol in combination with gemcitabine in patients with advanced malignancies.

BACKGROUND: Calcitriol, the active analogue of vitamin D, is antiproliferative and enhances the cytotoxicity of several anticancer agents, including gemcitabine. The vitamin D receptor (VDR) is expressed in the tumor stroma and treatment with VDR ligands results in stromal remodeling and increased intratumoral gemcitabine delivery. Furthermore, calcitriol can decrease the activity of the gemcitabine deactivating enzyme cytidine deaminase (CDD). Because hypercalcemia has been the most worrisome calcitriol-related adverse event, the less hypercalcemic agent paricalcitol may be preferred for further investigation. METHODS: The authors undertook a phase 1 study of gemcitabine in combination with escalating doses of paricalcitol administered weekly intravenously in patients with advanced cancers. A standard 3+3 dose escalation schema was used. Pharmacokinetic assessment of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) was performed. Pharmacodynamic assessment of paricalcitol was performed by measurement of CDD activity in peripheral blood mononuclear cells. RESULTS: A total of 44 patients were enrolled. Somnolence was the main dose-limiting toxicity. The highest dose of paricalcitol administered was 10.5 µg/kg. Hypercalcemia was infrequent and mild in severity. Paricalcitol did not appear to affect the pharmacokinetics of gemcitabine and dFdU. Evaluation of CDD activity was available for 9 patients; no clear trend for CDD activity after treatment with paricalcitol was established. The overall response rate was 4%; the rate of disease control was 67% in patients who were pretreated with gemcitabine. Progression-free and overall survival were 3.4 months and 6.5 months, respectively. CONCLUSIONS: Paricalcitol can be administered safely in doses up to 7 µg/kg weekly with fixed dose rate gemcitabine without dose-limiting hypercalcemia. To the best of the authors' knowledge, the maximum tolerated dose has not been formally established to date. Preliminary clinical activity deserves further exploration.

Paricalcitol supplementation during the first year after kidney transplantation does not affect calcification propensity score.

BACKGROUND: Cardiovascular complications are common in kidney transplant patients and calcification propensity of blood, measured as T50, is associated with cardiovascular outcomes. Paricalcitol supplementation affects calcium/phosphate homeostasis and may affect calcification propensity. To assess this hypothesis we measured T50 in kidney transplant recipients participating in a randomized study comparing paricalcitol versus no treatment during the first year after kidney transplantation. METHODS: Stored serum samples from 76 kidney transplant recipients (paricalcitol n = 37, no treatment n = 39) were analyzed. Analyses were performed at inclusion (8 weeks after transplantation) and repeated one year after transplantation. RESULTS: There were no statistically significant differences in T50 between the paricalcitol and placebo groups, neither at baseline (p = 0.56) nor at 1 year (p = 0.61). Also, there were no significant changes in T50 over time in either group or when pooling all data (p <  0.20). In multivariate regression analysis, out of 16 potentially relevant covariates, comprising clinical and biochemical parameters, only plasma PTH and T50 at baseline were significantly correlated to T50 after one year. (p <  0.03 and p < 0.01, respectively). CONCLUSIONS: Calcium propensity measured as T50 score remained unchanged with paricalcitol treatment in kidney transplant recipients, and was not changed over time during the study period of one year. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01694160 , registered 23 September 2012.

Hungry bone syndrome secondary to prostate cancer successfully treated with radium therapy.

A 50-year-old man with a history of prostate cancer with extensive bone metastasis and hypocalcaemia presented with muscle aches and cramps. Physical exam was significant for Chvostek's and Trousseau's sign. Laboratory assessment was consistent with profound hypocalcaemia. This was believed to be due to hungry bone syndrome secondary to advanced prostate cancer. He was treated with intravenous calcium, vitamin D and calcitriol. He also received three doses of radium223 therapy. After therapy, hypocalcaemic episodes resolved. Follow-up after 2.5 years showed continued resolution of hypocalcaemia.

Effect of one time high dose "stoss therapy" of vitamin D on glucose homeostasis in high risk obese adolescents

ABSTRACT Objective To study the effect of using a one time high dose "stoss therapy" of vitamin D2 (ergocalciferol: VD2) on indices of insulin sensitivity {whole body sensitivity index: WBISI} and secretion {insulinogenic index: IGI} measured during an oral glucose tolerance test (OGTT) in obese adolescents with VDD (25 OHD; serum metabolite of vit D: < 30 ng/dL). Subjects and methods In a randomized placebo controlled cross over design 20 obese adolescents with vitamin D deficiency (VDD) had baseline OGTT. Arm A received one time high dose 300,000 IU of ergocalciferol and Arm B received placebo. After 6 weeks the adolescents were reassigned to Arm A if they were in Arm B and vice versa. 25OHD, calcium, parathyroid hormone, comprehensive metabolic panel, urine calcium creatinine ratio were measured at each study visit. OGTTs to assess indices of sensitivity and secretion were done at baseline, 6 weeks and 12 weeks respectively. Results Adolescents were obese and insulin resistant (mean ± SD: mean age = 15.1 ± 1.9 years; BMI: 32.7 ± 9.8; homeostatic model of insulin resistance: HOMA-IR: 4.2 ± 2.8). Stoss therapy with VD2 increased 25OHD from baseline (16.7 ± 2.9 to 19.5 ± 4.5; p = 0.0029) when compared to the placebo. WBISI (2.8 ± 1.9) showed a trend towards improvement in Rx group (p = 0.0577) after adjustment for covariates. IGI (3 ± 2.2) showed an improvement in both Rx and placebo groups. Conclusions Our study demonstrated that using a high dose of VD2 (300,000 IU) did not have any beneficial effect on insulin sensitivity (whole body sensitivity index {WBISI}) and secretory indices (insulinogenic index {IGI}) in obese adolescents. High dose "stoss therapy" of VD2 did not appear to have any beneficial effect on glucose homeostasis on obese adolescents.

Alternative Oral Agents in Prophylaxis and Therapy of Uterine Fibroids-An Up-to-Date Review.

Uterine fibroids (UFs) are the most common tumors of the female genital tract. The effect of UFs on the quality of life and the overall cost of treatment are significant issues worldwide. Tumor size and location are the two specific factors which influence the occurrence of symptoms, the need for, and method of, treatment (some tumors require surgery while some can be treated with selected drugs). Primary prevention and treatment of early UF disease are worthy goals that might have a great impact on health care systems. Several treatments and prophylactic methods can be used in this endeavor. This publication presents current data about lesser-known substances which may have a beneficial effect on the treatment or prophylaxis of UFs and can be administered orally, serving as an alternative to (or complement of) surgery or selective progesterone receptor modulators (SPRMs). Early prevention and treatment of UFs in women from high-risk groups should be our priority. Innovative forms of UF management are under intensive investigation and may be promising options in the near future. Many of them evaluated vitamin D, paricalcitol, epigallocatechin gallate (EGCG), elagolix, aromatase inhibitors (AIs), and cabergoline and deemed them to be safe and effective. The next step in such projects should be properly constructed randomized control trials (RCTs), carried out by successive phases.

Impact of chocolate liquor on vascular lesions in apoE-knockout mice.

Cocoa polyphenols are thought to reduce the risk of cardiovascular diseases. Thus, cocoa-containing foods may have significant health benefits. Here, we studied the impact of chocolate liquor on vascular lesion development and plaque composition in a mouse model of atherosclerosis. Apolipoprotein E (apoE)-knockout mice were assigned to two groups and fed a Western diet that contained 250 g/kg of either chocolate liquor or a polyphenol-free isoenergetic control paste for 16 weeks. In addition to fat, protein, and fibers, the chocolate liquor contained 2 g/kg of polyphenols. Compared with the control group, mice fed the chocolate liquor had larger plaque areas in the descending aorta and aortic root, which were attributed to a higher mass of vascular smooth muscle cells (VSMCs) and collagen. Vascular lipid deposits and calcification areas did not differ between the two groups. The aortic tissue level of interleukin-6 (IL-6) mRNA was 5-fold higher in the mice fed chocolate liquor than in the control mice. Chocolate-fed mice exhibited an increased hepatic saturated to polyunsaturated fatty acid ratio than the controls. Although the chocolate liquor contained 14 µg/kg of vitamin D2, the chocolate liquor-fed mice did not have measurable 25-hydroxyvitamin D2 in the serum. These mice even showed a 25% reduction in the level of 25-hydroxyvitamin D3 compared with the control mice. Overall, present data may contribute to our understanding how chocolate constituents can impact vascular lesion development.

Paricalcitol as an Antiproteinuric Agent Can Result in the Deterioration of Renal and Heart Function in a Patient with Fabry Disease.

BACKGROUND Fabry disease is a rare and progressive X-linked inherited disorder of glycosphingolipid metabolism that is due to deficient or absent lysosomal a-galactosidase A activity. Among its other associated signs and symptoms, patients present with renal failure and proteinuria, which are markers of disease progression. Renin-angiotensin-aldosterone system (RAAS) blockers can slow the progression of chronic renal failure and proteinuria. In fact, some studies have shown the beneficial effects of paricalcitol on proteinuria. CASE REPORT We present a case of a female patient with the classic variant of Fabry disease. She was treated with a high dose of paricalcitol as an antiproteinuric agent due to unsatisfactory double-RAAS blockage, which resulted in transient worsening of cardiac and renal function. CONCLUSIONS Despite the positive effects of paricalcitol as an antiproteinuric agent, as previously shown by some authors, our case highlights the possible serious adverse effects associated with the use of high doses of this drug.

Vitamin D treatment modulates immune activation in cystic fibrosis.

Persistent inflammatory response in cystic fibrosis (CF) airways is believed to play a central role in the progression of lung damage. Anti-inflammatory treatment may slow lung disease progression, but adverse side effects have limited its use. Vitamin D has immunoregulatory properties. We randomized 16 CF patients to receive vitamin D2, vitamin D3 or to serve as controls, and investigated the effect of vitamin D supplementation on soluble immunological parameters, myeloid dendritic cells (mDCs) and T cell activation. Three months of vitamin D treatment were followed by two washout months. Vitamin D status at baseline was correlated negatively with haptoglobin, erythrocyte sedimentation rate and immunoglobulin A concentration. Total vitamin D dose per kg bodyweight correlated with the down-modulation of the co-stimulatory receptor CD86 on mDCs. Vitamin D treatment was associated with reduced CD279 (PD-1) expression on CD4+ and CD8+ T cells, as well as decreased frequency of CD8+ T cells co-expressing the activation markers CD38 and human leucocyte antigen D-related (HLA-DR) in a dose-dependent manner. There was a trend towards decreased mucosal-associated invariant T cells (MAIT) cell frequency in patients receiving vitamin D and free serum 25-hydroxyvitamin D (free-s25OHD) correlated positively with CD38 expression by these cells. At the end of intervention, the change in free-s25OHD was correlated negatively with the change in CD279 (PD-1) expression on MAIT cells. Collectively, these data indicate that vitamin D has robust pleiotropic immunomodulatory effects in CF. Larger studies are needed to explore the immunomodulatory treatment potential of vitamin D in CF in more detail.

Vitamin D deficiency as a public health issue: using vitamin D2 or vitamin D3 in future fortification strategies.

The role of vitamin D in supporting the growth and maintenance of the skeleton is robust; with recent research also suggesting a beneficial link between vitamin D and other non-skeletal health outcomes, including immune function, cardiovascular health and cancer. Despite this, vitamin D deficiency remains a global public health issue, with a renewed focus in the UK following the publication of Public Health England's new Dietary Vitamin D Requirements. Natural sources of vitamin D (dietary and UVB exposure) are limited, and thus mechanisms are needed to allow individuals to achieve the new dietary recommendations. Mandatory or voluntary vitamin D food fortification may be one of the mechanisms to increase dietary vitamin D intakes and subsequently improve vitamin D status. However, for the food industry and public to make informed decisions, clarity is needed as to whether vitamins D2 and D3 are equally effective at raising total 25-hydroxyvitamin D (25(OH)D) concentrations as the evidence thus far is inconsistent. This review summarises the evidence to date behind the comparative efficacy of vitamins D2 and D3 at raising 25(OH)D concentrations, and the potential role of vitamin D food fortification as a public health policy to support attainment of dietary recommendations in the UK. The comparative efficacy of vitamins D2 and D3 has been investigated in several intervention trials, with most indicating that vitamin D3 is more effective at raising 25(OH)D concentrations. However, flaws in study designs (predominantly under powering) mean there remains a need for a large, robust randomised-controlled trial to provide conclusive evidence, which the future publication of the D2-D3 Study should provide (BBSRC DRINC funded: BB/I006192/1). This review also highlights outstanding questions and gaps in the research that need to be addressed to ensure the most efficacious and safe vitamin D food fortification practices are put in place. This further research, alongside cost, availability and ethical considerations (vitamin D3 is not suitable for vegans), will be instrumental in supporting government, decision-makers, industry and consumers in making informed choices about potential future vitamin D policy and practice.

Vitamin D in Chronic Kidney Disease and Dialysis Patients.

Vitamin D deficiency (<20 ng/mL) and insufficiency (20-29 ng/mL) are common among patients with chronic kidney disease (CKD) or undergoing dialysis. In addition to nutritional and sunlight exposure deficits, factors that affect vitamin D deficiency include race, sex, age, obesity and impaired vitamin D synthesis and metabolism. Serum 1,25(OH)2D levels also decrease progressively because of 25(OH)D deficiency, together with impaired availability of 25(OH)D by renal proximal tubular cells, high fibroblast growth factor (FGF)-23 and decreased functional renal tissue. As in the general population, this condition is associated with increased morbidity and poor outcomes. Together with the progressive decline of serum calcitriol, vitamin D deficiency leads to secondary hyperparathyroidism (SHPT) and its complications, tertiary hyperparathyroidism and hypercalcemia, which require surgical parathyroidectomy or calcimimetics. Kidney Disease Outcomes Quality Initiative (KDOQI) and Kidney Disease Improving Global Outcomes (KDIGO) experts have recognized that vitamin D insufficiency and deficiency should be avoided in CKD and dialysis patients by using supplementation to prevent SHPT. Many vitamin D supplementation regimens using either ergocalciferol or cholecalciferol daily, weekly or monthly have been reported. The benefit of native vitamin D supplementation remains debatable because observational studies suggest that vitamin D receptor activator (VDRA) use is associated with better outcomes and it is more efficient for decreasing the serum parathormone (PTH) levels. Vitamin D has pleiotropic effects on the immune, cardiovascular and neurological systems and on antineoplastic activity. Extra-renal organs possess the enzymatic capacity to convert 25(OH)D to 1,25(OH)2D. Despite many unanswered questions, much data support vitamin D use in renal patients. This article emphasizes the role of native vitamin D replacement during all-phases of CKD together with VDRA when SHPT persists.

High-dose oral colecalciferol loading in obesity: impact of body mass index and its utility prior to bariatric surgery to treat vitamin D deficiency.

Obesity is associated with lower vitamin D levels compared with normal weight subjects, and if levels are not replaced prior to bariatric surgery, this can increase fracture risk as bone density typically falls post-operatively. We analysed the effect of body mass index (BMI) on vitamin D levels in response to 300 000 IU of colecalciferol in patients with vitamin D deficiency (<30 nmol L-1 ). Patients were grouped according to their BMI as normal weight (20-24.9 kg m-2 ), overweight (25-29.9 kg m-2 ), obese class I (30-34.9 kg m-2 ) and obese class II and above (>35 kg m-2 ). The records were retrospectively analysed to investigate the effects of BMI on vitamin D (total 25-hydroxy vitamin D [25(OH)D]), serum Ca2+ and parathyroid hormone (PTH) levels at 6, 12, 26 and 52 weeks compared with baseline. Compared with normal weight subjects, overweight and obese patients achieved lower mean peak total 25(OH)D levels (6 weeks post-loading), which was most significant in the class II and above group (mean total 25(OH)D levels 96.5 ± 24.2 nmol L-1 and 72.42 ± 24.9 nmol L-1 , respectively; P = 0.003). By 26 weeks, total 25(OH)D levels fell in all groups; however, there was now a significant difference between the normal weight subjects and all other groups (mean total 25(OH)D levels 84.1 ± 23.7 nmol L-1 ; 58 ± 20 nmol L-1 , P = 0.0002; 62.65 ± 19.2 nmol L-1 , P = 0.005; 59.2 ± 21 nmol L-1 , P = 0.005, respectively). Far fewer patients in the overweight and obese groups maintained levels above the recommended level of 75 nmol L-1 52 weeks post-loading (93%; 20%, P = 0.0003; 23%, P = 0.01; and 14%, P = 0.001, respectively). Alternative regimes for the treatment of vitamin D deficiency are needed in overweight and obese patients, especially those in whom bariatric surgery is planned.

Correction of vitamin D deficiency using sublingually administered vitamin D2 in a Crohn's disease patient with mal-absorption and a new ileostomy.

Vitamin D deficiency has been shown to be associated with many adverse health problems. Studies have shown that patients with Crohn's disease who have low vitamin D levels have a poorer quality of life than those with more adequate levels. It has also been shown that patients with mal-absorption problems have a difficult time achieving normal vitamin D levels in spite of aggressive supplementation, and that exposure to UVB radiation may be the most effective treatment option for these patients. We present a case in which 25-hydroxyvitamin D levels were normalized within 2 weeks in a severely vitamin D deficient patient with Crohn's disease with mal-absorption and a new ileostomy, utilizing sublingually administered vitamin D2. A 58 year-old white female was admitted with a new ileostomy following partial bowel resection due to complications from Crohn's disease. She was found to be severely vitamin D deficient at the time of admission, with a level of 6.1ng/ml on hospital day 3. Her treatment with vitamin D was delayed for a few days. She was initially treated with 5000 units of vitamin D3 orally twice a day for 3days (days 7-10). After discussion with the patient and obtaining her consent, vitamin D3 was stopped, and she was then treated with a total of 8 doses of 50,000 units of vitamin D2 administered sublingually. She was given the first 3 doses on alternating days (days 11, 13, 15), and then 5 more doses on consecutive days (days 17-21). The rise in her 25-hydroxyvitamin D level in response to treatment with sublingual vitamin D2 was significant. On day 10, after receiving 3days of orally administered vitamin D3, her level was 9.8ng/ml. One week later, after receiving 3 sublingual doses of vitamin D2, it rose to 20.3ng/ml. It was then measured on alternating days twice over the next 4days, and it rose to 45.5ng/ml, and then to 47.4ng/ml on the day of discharge to home. The major finding of this study is that sublingual administration of vitamin D2 appears to work effectively when intestinal absorption is impaired. The optimal dosing regimen still needs to be determined for the average Crohn's disease patient.