Long-term dietary antioxidant cocktail supplementation effectively reduces renal inflammation in diabetic mice

Diabetic nephropathy is a serious complication for diabetic patients, yet the precise mechanism that underlies the development of diabetic complications remains unknown. We hypothesised that dietary antioxidant supplementation with single N-acetylcysteine (NAC) or vitamin C combined with either vitamin E or vitamin E and NAC improves diabetic renal inflammation through the modulation of blood glucose levels, oxidative stress and inflammatory response. Experimental animals were treated with alloxan monohydrate to induce diabetes. Mice were divided into five groups and supplemented with single or a combination of antioxidants. Body weights and blood glucose levels were measured once a week. After 8 weeks of dietary antioxidant supplementation, mice were killed and blood urea N (BUN) and plasma creatinine levels were measured to evaluate renal function. NF-κB protein was indirectly demonstrated by the phosphorylated IκBα (pIκBα) level, and the expressions of oxidative stress- and inflammatory response-related proteins were also determined. We demonstrated that dietary antioxidant supplementation decreased lipid peroxidation levels demonstrated by thiobarbituric acid-reacting substances, BUN and plasma creatinine levels in diabetic kidneys. Moreover, dietary antioxidant cocktail supplementation improved blood glucose levels and selectively regulated the expressions of Cu-Zn superoxide dismutase, haeme oxygenase-1, pIκBα, inducible NO synthase, cyclo-oxygenase-2 and C-reactive protein in diabetic kidneys effectively. These findings demonstrated that diabetic renal failure was associated with inflammatory responses induced by hyperglycaemia. In addition, results in the study suggest that antioxidant cocktail supplementation may have beneficial effects on diabetic nephropathy through selective reduction of blood glucose levels and inflammatory response.     

Dietary calcium and vitamin D<Subscript>2</Subscript> supplementation with enhanced <Emphasis Type="Italic">Lentinula edodes</Emphasis> improves osteoporosis-like symptoms and induces duodenal and renal active calcium transport gene expression in mice

The two main sources of vitamin D₃ are de novo synthesis induced by exposure to ultraviolet (UV) light from the sun, and diet. Vitamin D₃ deficiency causes rickets or osteoporosis. Oak mushrooms (Lentinula edodes) that are exposed to UV radiation contain enhanced vitamin D₂ and have much higher calcium content than unmodified (non-irradiated) mushrooms. Such modified edible mushrooms have been proposed as a natural alternative source of dietary vitamin D. In the current study, we have examined whether modified oak mushrooms could improve or prevent osteoporosis-like symptoms in mice fed with low calcium and vitamin D₃-deficient diet. Four-week-old male mice were fed low calcium, vitamin D₃-deficient diets supplemented with 5, 10, or 20% unmodified, calcium-enhanced, or calcium plus vitamin D₂-enhanced oak mushrooms for 4 weeks. To assess the effects of the supplemented diets, we evaluated femur density and length, bone histology, the expression of active calcium transport genes, and serum calcium levels. Mice fed with low calcium and vitamin D₃-deficient diet developed osteoporosis-like symptoms within 4 weeks. Femur density and tibia thickness were significantly higher in mice fed calcium plus vitamin D₂-enhanced mushrooms, and the expression of duodenal and renal calcium transport genes was significantly induced. These results indicate that in mice, vitamin D₂ and/or calcium derived from irradiated oak mushrooms may improve bone mineralization through a direct effect on the bone, and by inducing the expression of calcium-absorbing genes in the duodenum and kidney.     

Vitamin D Resists Cyclophosphamide-Induced Genomic and DNA Damage in CHL Cells In Vitro and in Mice In Vivo

Vitamin D as an adjuvant therapy for cancer patients is hoped to have a beneficial outcome based on its physiological activity, but clinical trials so far by addition of vitamin D show unremarkable curative improvement, mechanism for explain this phenomena is not well-understood. The aim of this study was to determine whether vitamin D resists cyclophosphamide (CP)-induced genomic and DNA damage. In CHL cells in vitro, 1α,25-(OH)₂D₃ at 10, 50, and 100?nM was found to alleviate the frequency of chromosomal aberration with an alleviation range of 40.7–44.0%. There was a dose-dependent decrease for a proportion of γ-H2AX foci positive cells in response to an increase in 1α,25-(OH)₂D₃ concentration. Two vitamin D₃ injections of 1,000, 5,000, or 10,000?IU suppressed CP-induced micronucleus formation in mice BMCs with an alleviation range of 36.7–44.5%, mitigated lymphocytes DNA damage reflected by lower tail DNA, tail length and olive tail moment parameter in comet assay. Vitamin D showed an antagonistic effect on CP-induced genomic and DNA damage. Our data suggest that vitamin D as an adjuvant combine antineoplastic drug with genotoxicity administer to tumor patients is contraindicant.     

Correlation between Levels of Vitamins D3 and E in Type 2 Diabetes Mellitus: A Case-Control Study in Serdang,Selangor, Malaysia

An overview of vitamins D₃ and E suggests micronutrient deficiency contributes to type 2 diabetes mellitus (T2DM). A case-control study was conducted to determine the status of plasma vitamins D₃ and E isomers amongst diabetic Malaysians. Two groups were recruited for participation, one comprising fifty diabetic subjects (DM) and one comprising fifty non-diabetic (non-DM) subjects, in order to assess their plasma vitamin D₃, calcium and vitamin E status. Glycaemic status (haemoglobin A1c, HbA1c; fasting blood glucose, FBG; C-Peptide) and lipid profiles (total cholesterol, TC; triglycerides, TG; low-density lipoprotein-cholesterol, LDL-C; high-density lipoprotein-cholesterol, HDL-C) were assessed, followed by anthropometric measurements. The Mann–Whitney U-test, Kruskal–Wallis and Spearman’s correlation coefficient were used to elucidate the association between levels of plasma vitamins D₃ and E and T2DM. The vitamin D₃ deficiency group (<20 ng/mL) showed a significant correlation (p < 0.05) with glycaemic status (HbA1c and FBG) and lipid profiles (HDL-C, LDL and TC). Spearman’s correlation demonstrated that vitamin D₃ status is strongly correlated with HDL levels (p < 0.05). Similarly, plasma total vitamin E levels >4.9 μg/mL revealed significantly different FBG, HbA1c, C-Peptide, LDL, HDL and TC levels across both groups. Moreover, family history, smoking, waist circumference and HbA1c levels demonstrated a significant association (p < 0.05) with levels of vitamins D and E but not FBG and lipid profiles. This could be because the pre-diabetic status among the non-DM group influenced the outcomes of this study.     

Effects of calcium and vitamin D supplementation on blood pressure and serum lipids and carotenoids: a randomized,double-blind,placebo-controlled,clinical trial

PurposeTo estimate the effects of calcium or vitamin D supplementation or a combination of both on blood pressure and serum lipid and carotenoid levels.MethodsNinety-two colorectal adenoma patients were randomized in a pilot, double-blind, placebo-controlled clinical trial of supplemental vitamin D₃ 800 IU and elemental calcium 2.0 g (as calcium carbonate) alone or in combination in divided doses twice daily with meals over 6 months.ResultsRelative to placebo, mean serum triglycerides decreased 30% (P = .10) and 32% (P = .10) in the calcium and calcium plus vitamin D₃ treatment groups, respectively. When the two calcium intervention groups were pooled and compared with the pooled noncalcium groups, the estimated supplemental calcium treatment effects were statistically significant for triglycerides (P = .04). Similar but nonstatistically significant decreases (5%–7%) were observed for serum total cholesterol levels. Mean systolic blood pressure increased 6% (P = .08) in the calcium group; otherwise, there were no appreciable changes in systolic or diastolic blood pressures in any active treatment group. Mean serum total carotenoid levels decreased 14% (P = .07) in the calcium and 9% (P = .10) in the calcium plus vitamin D₃ groups.ConclusionsOur results suggest that supplemental calcium alone or combined with vitamin D₃ but not vitamin D₃ alone may reduce serum lipids and lipophilic micronutrients.     

The emerging evidence for vitamin D-mediated regulation of apolipoprotein A-I synthesis

Ischemic heart disease and cerebrovascular ischemia are leading causes of mortality in industrialized countries. The pathogenesis of these diseases involves the formation of atherosclerotic plaques with eventual rupture and superimposed thrombosis. This process is inhibited by high-density lipoprotein (HDL), the main protein component of which is apolipoprotein A-I (apo A-I). Vitamin D₃ is a hormone produced by sun-exposed skin but is acquired also in the diet. The Framingham Offspring Study and the Third National Health and Nutritional Examination Survey showed a link between vitamin D₃ intake and cardiovascular risk factors. The link between 25-hydroxyvitamin D₃ and HDL cholesterol (HDLc) and apo A-I is not as clear. Studies in vitamin D receptor knockout mice demonstrated higher HDLc and hepatic apo A-I messenger RNA expression relative to wild type. Experiments in cultured hepatocytes supported these observations. Human studies evaluating the relationship between vitamin D₃ and apo A-I and HDLc have yielded conflicting results, but most suggest a positive link between increasing vitamin D₃ levels and plasma apo A-I and HDLc. The purpose of this review is to examine the evidence linking vitamin D status and cardiovascular disease, to determine if there is a relationship between vitamin D levels and development of an atherogenic lipid profile. Our objectives are to determine if plasma vitamin D levels correlate with plasma HDLc and apo A-I and, if so, offer speculation as to how apo A-I in the context of high vitamin D levels provides enhanced atheroprotection.     

Abstracts on Calcium and Bone Metabolism

Objective: Vitamin D supplementation may be required for certain subgroups in the United States in whom status and intake are inadequate, but the impact of various doses, and whether calcium administration jointly or independently influences vitamin D metabolite levels, is unclear.

Methods: In a pilot chemoprevention trial of biomarkers of risk for colorectal adenoma, we measured the impact of vitamin D supplementation and/or calcium supplementation on plasma vitamin D metabolite concentrations. Ninety-two adult men and women living in the southeastern United States were randomized to 800 IU vitamin D₃, 2000 mg elemental calcium, both, or placebo daily for 6 months. We examined vitamin D status at baseline and postintervention and compared the change in plasma 25-hydroxyvitamin D (25(OH)D) and 1,25(OH)₂D levels by intervention group using general linear models.

Results: Eighty-two percent of the study population had insufficient plasma 25(OH)D concentrations (<75 nmol/L) at baseline, with the lowest levels observed among African American participants. Vitamin D supplements, with or without calcium supplementation, raised plasma 25(OH)D concentrations, on average, by 25 to 26 nmol/L. Half of the study participants were classified as having sufficient 25(OH)D status after 6 months of 800 IU of vitamin D₃ daily. Calcium alone did not influence 25(OH)D concentrations.

Conclusion: In this southeastern U.S. population, half of the study participants receiving 800 IU vitamin D₃ daily had blood 25(OH)D concentrations of ≤75 nmol/L after a 6-month intervention period, supporting higher vitamin D dose requirements estimated by some groups. More research is needed to identify the optimal vitamin D dose to improve 25(OH)D status in various at-risk populations.     

Long-Term Vitamin D3 Supplementation Does Not Prevent Colonic Inflammation or Modulate Bone Health in IL-10 Knockout Mice at Young Adulthood

Inflammatory bowel disease (IBD) is an idiopathic disease that can impair bone metabolism. Low vitamin D status has been implicated in its progress. This study used interleukin (IL)-10 knockout (KO) mice, that develop an intestinal inflammation when housed in a non-sterile environment, to determine if supplementation with vitamin D₃ throughout life could mitigate inflammation and attenuate the lower bone mineral content (BMC) and density (BMD), and bone strength. Female IL-10 KO mice were randomized 25 or 5000 IU vitamin D₃/kg diet throughout pregnancy and lactation. At weaning, offspring received the same or opposite diet as their mother until age three months. Body weight growth was similar among groups within a sex. At three months of age, there were no differences in inflammation and gene expression in the colon of offspring. Male offspring exposed to continuous 25 IU vitamin D₃/kg diet had lower (p < 0.001) colonic VDR expression and those exposed only to low vitamin D₃ until weaning had higher serum IL-6. There were no differences in femur or vertebral BMC, BMD or bone strength. In summary, long-term exposure to vitamin D₃ did not attenuate intestinal inflammation or preserve bone mineral or bone strength. Thus, supplementation with vitamin D₃ does not exert anti-inflammatory effects in this mouse model that mimics human inflammatory bowel disease.     

Effect of supplementation with fortified olive oil on biochemical markers of bone turnover in healthy women

Osteocalcin (OC) is a bone Gla protein synthesized by osteoblasts which have a high affinity for calcium. To adequately carboxylate OC to form carboxylated OC (cOC), the osteoblasts require sufficient vitamin K. If vitamin K is deficient, under-carboxylated OC (ucOC) is produced. The ratio between ucOC and cOC (UCR) as well as the levels of circulating ucOC are used as indicators of the vitamin K status of bone. The aim of the present study was to compare the vitamin K status of bone by measuring the plasma levels of ucOC and UCR in healthy adult women before and after 3 weeks of oral supplementation with 20 ml/day Petrini Plus extra virgin olive oil. Petrini Plus is an organic olive oil enriched with vitamins D₃, K₁ and B₆. Enrolled in the study were 15 healthy female volunteers (aged 25–40 years). Plasma levels of ucOC and cOC were measured by ELISA. ucOC was found to be reduced and UCR was reduced by 44% after Petrini Plus olive oil supplementation. Petrini Plus extra virgin olive oil might therefore be useful for bone protection as it was able to counteract bone loss in healthy volunteers.     

Vitamin C supplementation reconstitutes polyfunctional T cells in streptozotocin-induced diabetic rats

Background

Studies have demonstrated that vitamin C supplementation enhances the immune system, prevents DNA damage, and decreases the risk of a wide range of diseases. Other study reported that leukocyte vitamin C level was low in diabetic individuals compared with nondiabetic controls.

Aim of the work

To study the effect of vitamin C on oxidative stress, blood lipid profile, and T-cell responsiveness during streptozotocin (STZ)-induced type I diabetes mellitus.

Methods

Thirty male Sprague–Dawley rats were randomly split into three groups. The first served as a control group (n?=?10) in which rats were injected with the vehicle alone. The second (n?=?10) and the third groups (n?=?10) were rendered diabetic by intraperitoneal (i.p.) injection of single doses of STZ (60?mg/kg body weight). The third group was supplemented with vitamin C (100?mg/kg body weight) for 2?months.

Results

T lymphocytes from the diabetic rats were found to be in a stunned state, with a decreased surface expression of the CD28 costimulatory molecule, low levels of phosphorylated AKT, altered actin polymerization, diminished proliferation and cytokine production, and, eventually, a marked decrease in abundance in the periphery. Vitamin C was found to significantly decrease the elevated levels of blood hydroperoxide, glucose, cholesterol, triglycerides and low-density lipoprotein (LDL) in diabetic rats. Furthermore, it was found to restore CD28 expression, AKT phosphorylation, actin polymerization, and polyfunctional T cells (IFN-γ- and IL-2-producing cells that exhibit a high proliferation capacity).

Conclusion

Vitamin C treatment restores and reconstitutes polyfunctional, long-lived T cells in diabetic rats.     

Effects of Vitamin D3 and Calcium Supplementation on Serum Levels of Tocopherols,Retinol, and Specific Vitamin D Metabolites

γ-Tocopherol (γT) protects against DNA-damaging effects of nitrogen oxides, yet its physiologic regulation in vivo is unknown. Observational studies indicate inverse associations of 25[OH]-vitamin D with γT and leptin. To determine whether vitamin D₃ supplementation alters levels of lipid-soluble micronutrients, serum samples (N = 85 subjects) from a randomized, double-blind, placebo-controlled clinical trial of vitamin D₃ (800 IU) and calcium (2 g), alone and in combination, were analyzed for lipid micronutrients and specific vitamin D metabolites at baseline and after 6 mo of supplementation. Serum 25[OH]-vitaminD₃ levels increased 55% (P < 0.0001) and 48% (P = 0.0005), whereas 25[OH]-vitaminD₂ levels were lower by 48% (P = 0.26) and 21% (P = 0.36) in the vitamin D₃ and vitamin D₃ plus calcium groups, respectively. At baseline, γT levels were inversely associated with 25[OH]D (r = ?0.31, P = 0.004). With vitamin D₃ plus calcium treatment, serum α-tocopherol decreased 14% (P = 0.04), whereas similar changes in γT (19% lower, P = 0.14) were observed. No significant effects were observed for D₃ supplementation on leptin or retinol levels. These results are consistent with the hypothesis that vitamin D₃ ± calcium affects serum tocopherol and 25[OH]D₂ levels; however, studies using larger, more homogeneous populations are warranted.     

Effect of <Emphasis Type="Italic">Momordica grosvenori</Emphasis> on oxidative stress pathways in renal mitochondria of normal and alloxan-induced diabetic mice

Background Oxidative stress plays an important role in the pathogenesis of diabetes and diabetic nephropathy. Momordica grosvenori (MG), a traditional medicinal herb used as substitute sugar for obese and diabetes, exhibits anti-oxidative activity in vitro. Aim of the study This study investigated the effect of MG on renal mitochondrial lipid peroxidation, anti-oxidative defense system, and a potent oxidative stress–responsive protein, heme oxygenase-1 (HO-1) of non-diabetic and alloxan-diabetic mice in different stages of diabetes. Methods Male Balb/c mice were rendered diabetic by a single intra-peritoneal injection of alloxan (200 mg/kg), while control mice received sham saline injection. Control and diabetic mice were further subdivided according to their treatments: control (saline), low dose MG (150 mg/kg) and high dose MG (300 mg/kg), which were administered immediately after confirmation of hyperglycemia by gavage daily over an 8-week period. Mice were killed by cervical dislocation at 4th and 8th week, respectively, and serum and renal tissues were harvested. Serum glucose, lipid profile and renal function were evaluated; renal homogenate were subjected to determination of malondialdehyde (MDA) and glutathione (GSH) concentration, manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px) and HO-1 activities, together with Mn-SOD and HO-1 mRNA expression; paraffin-embedded renal tissues was used for routine histopathological examination. Results Short-term diabetes caused hyperglycemia and intensified oxidative stress in renal mitochondrial demonstrated by higher MDA and lower GSH levels than control group, accompanied by increased mRNA expression and activity of HO-1 and Mn-SOD, and augmented GSH-Px activity. Low dose of MG administration ameliorated hyperglycemia, inhibited HO-1 and Mn-SOD mRNA expression and reduced HO-1, Mn-SOD, GSH-Px activities. Diabetic mice did not demonstrate early symptoms of diabetic nephropathy until 8th week, characterized by hyperglycemia, hyperlipidemia, and renal damage. A progressive increment in MDA level and decrease in GSH level, as well as reduced mRNA expression and activity of Mn-SOD and HO-1 in the kidney were observed. Low dose of MG attenuated diabetic nephropathy symptoms partially, inhibited lipid peroxidation, up-regulated HO-1 and Mn-SOD mRNA expression, and increased HO-1 activity. Conclusions The study confirmed the involvement of oxidative stress in the development of diabetes mediated by the pro- and anti-oxidant role of HO-1, and pointed to the possible anti-oxidative mechanism of the anti-diabetic and nephroprotective action of MG.     

Antioxidants and cognitive training interact to affect oxidative stress and memory in APP/PSEN1 mice

Abstract

The present study investigated the relationships among oxidative stress, β-amyloid and cognitive abilities in the APP/PSEN1 double-transgenic mouse model of Alzheimer's disease. In two experiments, long-term dietary supplements were given to aged APP/PSEN1 mice containing vitamin C alone (1 g/kg diet; Experiment 1) or in combination with a high (750 IU/kg diet, Experiments 1 and 2) or lower (400 IU/kg diet, Experiment 2) dose of vitamin E. Oxidative stress, measured by F₄-neuroprostanes or malondialdehyde, was elevated in cortex of control-fed APP/PSEN1 mice and reduced to wild-type levels by vitamin supplementation. High-dose vitamin E with C was less effective at reducing oxidative stress than vitamin C alone or the low vitamin E+C diet combination. The high-dose combination also impaired water maze performance in mice of both genotypes. In Experiment 2, the lower vitamin E+C treatment attenuated spatial memory deficits in APP/PSEN1 mice and improved performance in wild-type mice in the water maze. Amyloid deposition was not reduced by antioxidant supplementation in either experiment.     

An update on UK Vitamin D intakes and status,and issues for food fortification and supplementation

Vitamin D is unique among the essential nutrients in that it can be made in the body via exposure of the skin to sunlight. There are few rich sources of vitamin D in the diet. Vitamin D is essential for maintaining healthy bones and deficiency of vitamin D causes rickets in children and osteomalacia in adults. In the UK, there is evidence that low vitamin D status is prevalent in the population and older adults living in institutions are particularly at risk. There are two forms of vitamin D that can be added to foods and drinks: vitamin D₂ and D₃. They have somewhat different structures, and there are some differences in the way they are metabolised by the body. Overall, the evidence for the relative effectiveness of vitamin D₂ vs. D₃ is mixed, and more studies are needed to provide a clearer picture. However, there does seem to be some indication that D₃ is more effective than D₂ in raising vitamin D status.     

Assessing the Relationship between Vitamin D3 and Stratum Corneum Hydration for the Treatment of Xerotic Skin

Vitamin D₃ has been called the “sunshine” vitamin since the formation of vitamin D is mediated by exposure to sunlight. Vitamin D₃ is linked to many health benefits, however serum levels of vitamin D₃ have been decreasing over the last few decades and the lower levels of vitamin D₃ may have consequences on normal physiology. We investigated the association between serum 25-hydroxyvitamin D (25(OH)D) levels and stratum corneum conductance as well as the effect of topical application of cholecalciferol (vitamin D₃) on dry skin. Eighty three subjects were recruited and blood serum levels and skin conductance measurements were taken after a one week washout. A correlation was observed between vitamin D levels and skin moisture content, individuals with lower levels of vitamin D had lower average skin moisture. Subsequently, a 3-week split leg, randomized, vehicle controlled clinical study was conducted on a subset of 61 of the above individuals who were identified with non-sufficient vitamin D serum levels. Topical supplementation with cholecalciferol significantly increased measurements of skin moisturization and resulted in improvements in subjective clinical grading of dry skin. Taken together our finding suggest a relationship between serum vitamin D₃ (25(OH)D) levels and hydration of the stratum corneum and further demonstrate the skin moisture benefit from topical application of vitamin D₃.     

Effects of in vitro vitamin D treatment on function of T cells and autophagy mechanisms in high-fat diet-induced obese mice

BACKGROUND/OBJECTIVESObesity is associated with the impaired regulation of T cells characterized by increased numbers of Th1 and Th17 cells and the dysregulation of vitamin D metabolism. Both obesity and vitamin D have been reported to affect autophagy; however, a limited number of studies have investigated the effects of vitamin D on T cell autophagy in obese mice. Therefore, we aimed to determine whether in vitro treatment with vitamin D affects the proliferation, function, and autophagy of T cells from obese and control mice.MATERIALS/METHODSFive-week-old male C57BL/6 mice were fed control or high-fat diets (10% or 45% kcal fat: CON or HFDs, respectively) for 12 weeks. Purified T cells were stimulated with anti-CD3 and anti-CD28 monoclonal antibodies and cultured with either 10 nM 1,25(OH)₂D₃ or 0.1% ethanol (vehicle control). The proliferative response; expression of CD25, Foxp3, RORγt, and autophagy-related proteins (LC3A/B, SQSTM1/P62, BECLIN-1, ATG12); and the production of interferon (IFN)-γ, interleukin (IL)-4, IL-17A, and IL-10 by T cells were measured.RESULTSCompared with the CON group, T cell proliferation tended to be lower, and the production of IFN-γ was higher in the HFD group. IL-17A production was reduced by 1,25(OH)2D₃ treatment in both groups. The LC3 II/I ratio was higher in the HFD group than the CON group, but P62 did not differ. We observed no effect of vitamin D treatment on T cell autophagy.CONCLUSIONSOur findings suggest that diet-induced obesity may impair the function and inhibit autophagy of T cells, possibly leading to the dysregulation of T cell homeostasis, which may be behind the aggravation of inflammation commonly observed in obesity.     

Comprehensive Safety Monitoring of 12‐Month Daily 7000‐IU Vitamin D3 Supplementation in Human Immunodeficiency Virus–Infected Children and Young Adults

Background: There is uncertainty whether long‐term daily dosing with vitamin D₃ (cholecalciferol) supplementation (vitD₃) above the 4000‐IU/d dietary reference intake upper tolerable limit in children and adults is safe. As part of a randomized placebo‐controlled trial, we determined if supplementation with 7000‐IU/d vitD₃ for 12 months in human immunodeficiency virus (HIV)–Infected subjects was safe and/or associated with metabolic outcomes. Material and Methods: A total of 58 HIV‐infected subjects—aged 9–24.9 years and stratified by mode of HIV acquisition (perinatal or behavioral)—were recruited, randomized to 7000‐IU/d vitD₃ or placebo, and followed at 3, 6, and 12 months with physical examinations, blood and urine sampling for measures of 25(OH)D (serum 25‐hydroxyvitamin D), metabolic status, safety measures, and HIV immune status. Safety was defined by a low incidence (<5%) of the study‐defined serious adverse events—that is, elevated serum calcium plus 25(OH)D >160 ng/mL—and no changes in hematologic, liver, renal, metabolic, lipid, or inflammatory status. Results: Randomization groups did not differ in demographic characteristics, vitamin D status, or HIV disease status at baseline. Over the 12 months, serum 25(OH)D increased with supplementation. No subject experienced a serious adverse safety event; none had 25(OH)D >80 ng/mL at any time. There were no clinically significant changes in hematologic, liver, renal, metabolic, lipid, or inflammatory status. Conclusions: Safety of daily 7000‐IU vitD₃ supplementation in children and young adults with HIV was comprehensively monitored over 12 months. High‐dose daily vitD₃ supplementation was efficacious in improving vitamin D status, and there were no safety events.     

A new method for the determination of vitamin D3 and 25-hydroxyvitamin D3 in meat

The total vitamin D content in meat, i.e., vitamin D₃ and 25-hydroxyvitamin D₃, was determined by HPLC after alkaline hydrolysation, solid-phase extraction and semi-preparative HPLC. For detection, a DAD detector between 220 and 320 nm was used and quantification was performed at 265 nm. Vitamin D₂ was used as internal standard for vitamin D₃ as well as for 25-hydroxyvitamin D₃. Precision for vitamin D₃ was determined in lean meat and lard to 9.1% and 7.1%, respectively. The corresponding values for 25-hydroxyvitamin D₃ were 8.9% and 9.9%. Accuracy was determined in spiked samples, which showed a recovery of 94.7% and 99.0% for vitamin D₃ and 25-hydroxyvitamin D₃, respectively. The method is applicable for establishing data for food composition tables.     

Determination of vitamin D3 and 25-hydroxyvitamin D3 in foodstuffs by HPLC UV-DAD and LC–MS/MS

In order to generate new data for vitamin D content for the Canadian Nutrient File, a method for the quantification of vitamin D₃ and 25(OH)D₃ in foodstuffs has been modified and improved. Vitamin D₃ was quantified using reverse phase liquid chromatography (LC) with UV-diode array detector (UV-DAD), while 25(OH)D₃ was measured by triple quadrupole mass spectrometry (APCI MS/MS). Quantification was by internal standards (IS) using vitamin D₂ and 25(OH)D₂. A Certified Reference Material (CRM-421 containing vitamin D₃) and a control sample (internally generated reference material of ground pork containing both vitamin D₃ and 25(OH)D₃) were used as validation and quality control tools. Limit of detection for both compounds was 0.04 μg/100 g. Accuracy for vitamin D in the CRM-421 was 99% (0.142 mg/kg for a target of 0.143, n = 10). Recovery of vitamin D₃ in ground pork was 97% (88% absolute recovery). For 25(OH)D₃, a recovery of 94% (73% absolute recovery) was obtained. Using this method, data for vitamin D₃ and 25(OH)D₃ content in a variety of foods (pork, beef, eggs, poultry, fish, and dinners) have been generated.     

Lyophilized carrot ingestion lowers lipemia and beneficially affects cholesterol metabolism in cholesterol–fed C57BL/6J mice

Summary Background Several lines of evidence indicate that diet rich in fruit and vegetable can protect against cardiovascular diseases by acting on cholesterol metabolism and on oxidative stress. Aim of the study The aim of this study was to assess whether daily carrot consumption (provided as lyophilized powder) could differentially influence the consequences of cholesterol supplementation on lipid metabolism and oxidative stress in C57BL/6J mice. Methods Fourteen mice were randomized in four groups. Mice were fed either control diets (without or with 0.25% cholesterol added) or lyophilized carrot enriched diets (20% wt/wt without or with 0.25 % cholesterol added) for 4 weeks. Cholesterol and triglycerides in plasma and in liver were measured at the end of the experimental period. Fecal excretion of sterols was evaluated. Vitamin E and carotenoid concentrations were also determined. Several biomarkers relative to oxidative stress such as FRAP (Ferric Reducing Ability of Plasma) and isoprostanes were investigated. Results Feeding the carrot diet resulted in a decrease of cholesterol (–41%) and triglycerides (–49 %) in plasma and in the liver (–41% and –39%, respectively) in animals fed cholesterol–supplemented diets. Carrot diet induced an increase of total neutral sterols fecal excretion, which inhibits digestive cholesterol absorption. Carrot diet increased antioxidant status in cholesterolfed mice as related by the 16% higher FRAP values. Although vitamin E was not affected by carrot diet, vitamin E/TG ratio was significantly higher in animals fed carrot diets. The carrot diet induced an increase of vitamin E in the heart in both cholesterol–free and cholesterol–supplemented mice suggesting a higher protection of this tissue. Conclusion This study shows that carrot ingestion decreases lipemia and improves antioxidant status in mice. Such results suggest that carrot intake may exert a protective impact against CVD linked to atherosclerosis. It is likely that these effects could be due to the synergistic effect of fiber and associated antioxidants.