Urinary Excretion Of Vitamin Research Articles

Vitamin C Urinary Loss in Fabry Disease: Clinical and Genomic Characteristics of Vitamin C Renal Leak

BackgroundReduced plasma vitamin C concentrations in chronic diseases may result from abnormal urinary excretion of vitamin C: a renal leak. We hypothesized that vitamin C renal leak may be associated with disease-mediated renal dysregulation, resulting in aberrant vitamin C renal reabsorption and increased urinary loss. ObjectivesWe investigated the prevalence, clinical characteristics, and genomic associations of vitamin C renal leak in Fabry disease, an X-linked lysosomal disease associated with renal tubular dysfunction and low plasma vitamin C concentrations. MethodsWe conducted a non-randomized cross-sectional cohort study of men aged 24–42 y, with Fabry disease (n = 34) and controls without acute or chronic disease (n = 33). To match anticipated plasma vitamin C concentrations, controls were placed on a low-vitamin C diet 3 wk before inpatient admission. To determine the primary outcome of vitamin C renal leak prevalence, subjects were fasted overnight, and matched urine and fasting plasma vitamin C measurements were obtained the following morning. Vitamin C renal leak was defined as presence of urinary vitamin C at plasma concentrations below 38 μM. Exploratory outcomes assessed the association between renal leak and clinical parameters, and genomic associations with renal leak using single nucleotide polymorphisms (SNPs) in the vitamin C transporter SLC23A1. ResultsCompared with controls, the Fabry cohort had 16-fold higher odds of renal leak (6% vs. 52%; OR: 16; 95% CI: 3.30, 162; P < 0.001). Renal leak was associated with higher protein creatinine ratio (P < 0.01) and lower hemoglobin (P = 0.002), but not estimated glomerular filtration rate (P = 0.54). Renal leak, but not plasma vitamin C, was associated with a nonsynonymous single nucleotide polymorphism in vitamin C transporter SLC23A1 (OR: 15; 95% CI: 1.6, 777; P = 0.01). ConclusionsIncreased prevalence of renal leak in adult men with Fabry disease may result from dysregulated vitamin C renal physiology and is associated with abnormal clinical outcomes and genomic variation.

Vitamin C Urinary Loss in Fabry Disease: Clinical and Genomic Factors of Vitamin C Renal Leak

ObjectivesReduced plasma vitamin C concentrations in chronic diseases may result from abnormal urinary excretion of vitamin C excretion: a renal leak. We hypothesized that vitamin C renal leak may be the consequence of disease-mediated dysregulation affecting the renal tubules, resulting in aberrant vitamin C renal reabsorption and increased urinary loss. The study objective was to investigate the prevalence, clinical characteristics, and genomic associations of vitamin C renal leak in Fabry disease, an X-linked lysosomal storage disease associated with renal tubular dysfunction and low plasma vitamin C concentration.MethodsThis was a non-randomized cross-sectional cohort study of males with Fabry disease (n = 34) and healthy male controls (n = 33). To determine primary outcome of vitamin C renal leak, matched urine and fasting plasma vitamin C measurements were obtained following an overnight fast. Based on data from healthy men, vitamin C renal leak was defined as presence of urinary vitamin C at plasma concentrations below 38 µM. Exploratory outcomes assessed the association between renal leak and clinical parameters; and genomic associations with renal leak using single nucleotide polymorphisms (SNPs) in the vitamin C transporter SLC23A1. Proof-of-concept studies were conducted using two mouse models.ResultsCompared with healthy men, Fabry cohort had 16-fold higher odds of renal leak (6% vs 52%: OR16, P < 0.001). Renal leak was associated with higher protein creatinine ratio (p = 0.01), lower hemoglobin (p = 0.002) and hematocrit (p = 0.008). Renal leak, but not plasma vitamin C, was associated with a non-synonymous single nucleotide polymorphism in vitamin C transporter SLC23A1 (p = 0.01 and p = 0.47 respectively). Using two mouse models, we recapitulated the relationships between renal leak, dysregulated vitamin C renal reabsorption and low plasma vitamin C concentrations.ConclusionsIncreased prevalence of vitamin C renal leak in Fabry disease may result from dysregulated vitamin C renal physiology, with significant clinical and genomic associations. Renal leak may be more sensitive than plasma vitamin C in evaluating genomic associations in small cohorts.Funding SourcesIntramural Research Program, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD 20,892–1372.

P547 Inadequate vitamin C status and association with inflammatory biomarkers in adults with active Crohn’s disease

Abstract Background Micronutrient deficiencies are common in inflammatory bowel disease (IBD) due to the inflammatory burden and changes in dietary intake. Vitamin C, an essential water-soluble antioxidant required for tissue repair and immune function, is found primarily in fresh fruit and vegetables however, this food group is more often avoided by people with IBD compared with the general population. This research aimed to determine serum vitamin C status in subjects with active Crohn’s disease, measure urinary vitamin C excretion in healthy controls (HC) and Crohn’s disease patients before and after exclusive enteral nutrition (EEN) and assess associations between inflammatory markers and vitamin C. Methods Stored serum and random urine samples prospectively collected from adults with mild to moderately active Crohn’s disease and adult HC were analysed. Both HC and Crohn’s disease groups received EEN with a known vitamin C content for two weeks. Serum and urinary vitamin C were measured using high-performance liquid chromatography with electrochemical detection. Urinary vitamin C was standardised to urinary creatinine. Non-parametric t-tests and correlations were performed. Results EEN was initiated in 38 patients (aged 16 to 39 years old). Inadequate serum vitamin C (&amp;lt;50 µmol/l) was present in 36/38 patients with active Crohn’s disease and 45% had hypovitaminosis C. Baseline C-reactive protein (CRP) was 12 mg/l (range, 3 to 158 mg/l) and faecal calprotectin was 1065 µg/g (range, 60 to 3838 µg/g). Serum vitamin C correlated weakly with CRP (r = −0.30 95% CI: −0.58 to 0.03, p = 0.06) but not with faecal calprotectin. Two weeks of EEN was completed by 30 (79%) patients and 17 (81%) HC. The average vitamin C intake was 168mg/day (range, 108–252 mg/day). Baseline urinary excretion of vitamin C was low in both Crohn’s disease and HC. Following EEN urinary vitamin C excretion increased significantly in both groups (Figure 1). Conclusion Patients with active Crohn’s disease had inadequate vitamin C status. EEN increased urinary vitamin C excretion in both Crohn’s disease and HC, suggesting low baseline dietary vitamin C intake and potentially enhanced utilisation. Further research with a larger patient cohort would provide a greater understanding of vitamin C metabolism in active Crohn’s disease.

Evaluation of the Efficacy and Tolerability of Vitamin Complexes in Marmalade Pastilles in Healthy Children and Children With Allergic Diseases of Pre-School and School Age

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Assessment of vitamin supply in preschoolers

Objective : to assess the vitamin status of preschoolers according to the results of one-hour urinary vitamin excretion and the data of actual nutrition. Subjects and methods . A survey was conducted in winter 2016, covering 33 children (19 boys and 14 girls) aged from 2 to 7 years who went to a Yekaterinburg preschool educational institution. The amount of essential nutrients was calculated according to the data of actual nutrition during 5 days. The vitamin status was evaluated from the urinary excretion of thiamine, riboflavin, and 4-piridoxyl acid, by testing a morning fasting urine portion. Results. Determination of urinary excretion revealed deficiency of vitamin B2 in 24.2% of the examinees, and that of vitamins B1 and B6 in significantly more children (in 66.7–69.7%). According to the actual nutrition data, inadequate intakes of vitamins B2, A, and C were detected in 27.3–30.3% of the examinees, those of niacin and vitamin B1 in 54.5 and 69.7%, respectively. The proportion of the coincidental data obtained by two methods for assessing the vitamin status was 63.6% for vitamin B1 and 69.7% for vitamin B2. Conclusion . The findings suggest that the two methods to assess the supply of vitamins B1 and B2 are interchangeable and the children need additional vitamin intakes.

Dietary Resistant Starch Prevents Urinary Excretion of Vitamin D Metabolites and Maintains Circulating 25-Hydroxycholecalciferol Concentrations in Zucker Diabetic Fatty Rats

Background:Type 2 diabetes (T2D) is the leading cause of nephropathy in the United States. Renal complications of T2D include proteinuria and suboptimal serum 25-hydroxycholecalciferol (25D) concentrations. 25D is the major circulating form of vitamin D and renal reabsorption of the 25D–vitamin D–binding protein (DBP) complex via megalin-mediated endocytosis is believed to determine whether 25D can be activated to 1,25-dihydroxycholecalciferol (1,25D) or returned to circulation. We previously demonstrated that excessive urinary excretion of 25D–DBP and albuminuria occurred in rats with type 1 diabetes (T1D) and T2D. Moreover, feeding rats with T1D high-amylose maize partially resistant to digestion [resistant starch (RS)] prevented excretion of 25D–DBP without significantly affecting hyperglycemia. Objective:We used Zucker diabetic fatty (ZDF) rats, a model of obesity-related T2D, to determine whether feeding RS could similarly prevent loss of vitamin D and maintain serum 25D concentrations. Methods:Lean control Zucker rats (n = 8) were fed a standard semi-purified diet (AIN-93G) and ZDF rats were fed either the AIN-93G diet (n = 8) or the AIN-93G diet in which cornstarch was replaced with RS (550 g/kg diet; 35% resistant to digestion) (n = 8) for 6 wk. Results:RS attenuated hyperglycemia by 41% (P < 0.01) and prevented urinary DBP excretion and albuminuria, which were elevated 3.0- (P < 0.01) and 3.6-fold (P < 0.01), respectively, in control diet–fed ZDF rats. Additionally, urinary excretion of 25D (P = 0.01) and 1,25D (P = 0.03) was higher (89% and 97%, respectively), whereas serum 25D concentrations were 31% lower (P < 0.001) in ZDF rats fed the control diet compared with RS-fed ZDF rats. Histopathologic scoring of the kidney revealed that RS attenuated diabetes-mediated damage by 21% (P = 0.12) despite an ∼50% decrease in megalin protein abundance. Conclusions:Taken together, these data provide evidence that suggests vitamin D balance can be maintained by dietary RS through nephroprotective actions in T2D, which are independent of vitamin D supplementation and renal expression of megalin.

Dietary resistant starch prevents urinary excretion of vitamin D metabolites and restores circulating 25‐hydroxycholecalciferol concentrations in the Zucker diabetic fatty rat (1041.3)

Type 2 diabetes (T2D) is an epidemic that leads to renal disease if left untreated. Compromised renal function has been implicated in vitamin D deficiency as the renal proximal tubule maintains circulating 25‐hydroxycholecalciferol (25D) concentrations as well as its activation to 1,25‐dihydroxycholecalciferol (1,25D). We previously showed that feeding high‐amylose maize that is partially resistant to digestion (RS) prevented excretion of 25D‐vitamin D‐binding protein (DBP) and albumin in T1D rats. Here, we utilized Zucker diabetic fatty rats (ZDF) to determine whether dietary RS could prevent excessive excretion of vitamin D metabolites and maintain serum 25D level. Lean control Zucker (n=8) rats were fed a control diet (AIN‐93G) and ZDF were fed either the AIN‐93G diet (n=8) or the AIN‐93G diet in which cornstarch was replaced by RS (n=8) for 6 week. RS attenuated hyperglycemia by 41% and prevented excretion of DBP and albumin. Urinary 25D and 1,25D concentrations were 89% and 97% lower, respectively, while serum 25D levels were 40% higher in RS‐fed ZDF compared to ZDF fed the control diet. mRNA expression of CYP27B1 and CYP24A1, which are essential in vitamin D metabolism, were not affected by diabetes or RS. Collectively, these data suggested that vitamin D balance is dependent on the absence of proteinuria, which can be prevented by dietary RS in T2D independent of vitamin D supplementation.

Urinary excretion of B-group vitamins reflects the nutritional status of B-group vitamins in rats.

We have reported previously that the urinary excretion of B-group vitamins reflects recent dietary intakes of these vitamins. We also proposed reference values for the urinary levels of B-group vitamins for human subjects, and used these for evaluating human nutritional status. However, the question arises as to whether the urinary excretion of B-group vitamins in animals or human subjects decreases immediately before they become B-group vitamin insufficient or when fed a diet low in vitamins. In the present study, rats were fed a vitamin-free diet for 5d, and changes in the levels of B-group vitamins in urine and blood were monitored. Urinary excretion of vitamin B1, vitamin B2, 4-pyridoxic acid (a catabolite of vitamin B6), pantothenic acid, folate and biotin steeply decreased, and all of the values reached zero within 1-2d. With respect to blood, the concentrations of only three of the eight B-group vitamins (vitamin B1, pyridoxal phosphate and biotin) decreased to 15% (P<0·0001), 7% (P<0·0001) and 2% (P<0·0001) on day 5, respectively, compared with the values at the beginning of the experiment. The decrease was more rapid and the changes were greater in the urine samples than in the blood samples. The present data complement our previous proposal that the urinary excretion of B-group vitamins reflects the nutritional status of these vitamins.

Urinary Excretion of Water-Soluble Vitamins Increases in Streptozotocin-Induced Diabetic Rats without Decreases in Liver or Blood Vitamin Content

It is thought that the contents of water-soluble vitamins in the body are generally low in diabetic patients because large amounts of vitamins are excreted into urine. However, this hypothesis has not been confirmed. To investigate this hypothesis, diabetes was induced in male Wistar rats (6 wk old) by streptozotocin treatment, and they were then given diets containing low, medium or sufficient vitamins for 70 d. The contents of 6 kinds of B-group vitamins, namely vitamin B₁, vitamin B₂, vitamin B₆, vitamin B₁₂, folate and biotin, were determined in the urine, blood and liver. No basic differences among the dietary vitamin contents were observed. The urinary excretion of vitamins was higher in diabetic rats than in control rats. The blood concentrations of vitamin B₁₂ and folate were lowered by diabetes, while, those of vitamin B₁, vitamin B₂, vitamin B₆, and biotin were not. All liver concentrations of vitamins were increased in diabetic rats above those in control rats. These results showed that streptozotocin-induced diabetes increased urinary excretion of water-soluble vitamins, though their blood and liver concentrations were essentially maintained in the rats.

Urinary Excretion of Vitamin K Metabolites in Term and Preterm Infants: Relationship to Vitamin K Status and Prophylaxis

Little is known about the metabolic turnover and excretion of vitamin K in healthy newborn infants and the metabolic consequences of prophylactic regimens designed to protect against vitamin K deficiency bleeding (VKDB). We measured the excretion of two urinary metabolites (≤ 24 h) of vitamin K (5C- and 7C-aglycones) in term infants before (n = 11) and after (n = 5) a 1000 μg i.m. dose of vitamin K1 (K1) and in preterm infants after 200 μg i.m. (n = 4), 500 μg i.m. (n = 4), or 200 μg i.v. (n = 5). In preterm infants, we also measured serum K1, vitamin K1 2,3-epoxide, and PIVKA-II at 5 d postpartum. Before prophylaxis, the rate of 5C- and 7C-aglycone excretion was 25 times lower than adults, reflecting low vitamin K stores at birth. After prophylaxis, the excretion rate correlated to K1 dose (r = 0.6) but was two orders of magnitude lower than that in adults, probably reflecting the immaturity of neonatal catabolism. All term and 10 of 13 preterm infants mainly excreted 5C-aglycone. We present evidence that increased excretion of the 7C-aglycone was associated with metabolic overload because of the exposure to high-tissue K1 concentrations. Measurement of the 5C- and 7C-aglycones may facilitate longitudinal studies of vitamin K status in neonates and aid the development of improved prophylactic regimens.

Urinary excretion of vitamin B1, B2, B6, niacin, pantothenic acid, folate, and vitamin C correlates with dietary intakes of free-living elderly, female Japanese

We hypothesized that 24-hour urinary excretion of water-soluble vitamins might correlate with their intake in free-living Japanese elderly females aged 70 to 84 years. We performed a cross-sectional study composed of 37 healthy, elderly, Japanese females living freely. All foods and the corresponding weights consumed for 4 consecutive days were recorded accurately. A 24-hour urine sample was collected on the fourth day, and the urinary content of water-soluble vitamins was measured. The urinary levels of all vitamins, except for B(12) (r = 0.01; P = .936), were correlated positively with the mean intake over the recent 4 days (vitamin B1: r = 0.62; P < .001; vitamin B2: r = 0.57; P < .001; vitamin B6: r = 0.37; P < .005; niacin: r = 0.54; P < .001; niacin equivalents: r = 0.54; P < .001; pantothenic acid: r = 0.59; P < .001; folate: r = 0.55; P = .001; and vitamin C: r = 0.53; P < .001). Mean estimated intakes of water-soluble vitamins calculated using urinary concentrations and recovery rates showed 96% to 107% of their 3-day mean intake, except for vitamin B12 (65%). We conclude that urinary levels of water-soluble vitamins, except for B12, reflected their recent intake in free-living Japanese elderly females and could be used as a measure of their intake during the previous few days both for group means and for individual rankings within a group.

Vitamin C twice a day enhances health

This review provides information determining how much vitamin C to take, including analysis of the recent findings, which demonstrate advantages and problems with higher daily doses. The Daily Value for vitamin C was raised to 90 mg for men in 2000, and Upper Limit of 2,000 mg per day was established as being safe. This followed a study of urinary excretion of vitamin C (AA) that demonstrated 500 mg twice a day provides levels sufficient to cause continuous urinary excretion in humans. That is the lowest oral dosage evaluated that significantly saturates blood plasma. A later study endorsed 200 mg from dietary sources for the RDA. Even though plasma concentration of AA is then significantly lower, at 200 mg daily certain white blood cells are saturated with AA. Recently many studies have indicated the benefit of high levels of AA to maintain the brain, bones, and heart, reduce damage from stroke, brain trauma, and cataracts, and lower the risk of cancer metastasis and colds. Pro-oxidant activity has been found only for i.v. adminstration, where high concentrations appear effective destroying tumor cells while not harming normal cells. This review evaluates recent research and finds it consistent with the hypothesis that people, especially older people and soldiers in combat environments, are likely to benefit if they maintain the saturating level of AA by taking 500mg supplements twice a day.

Urinary excretion of vitamin B12 depends on urine volume in Japanese female university students and elderly

Recent studies have shown that urinary excretion of water-soluble vitamins reflects their intake in humans. However, some have reported that physical characteristics and urine volume may affect the amount of vitamin compounds found in urine. We hypothesized that physical characteristics and urine volume could affect urinary excretion of B-group vitamins. Twenty-four-hour urine samples were collected from 186 free-living Japanese women aged 19 to 21 years and 104 free-living Japanese subjects aged 70 to 84 years. Correlations between urinary output of each B-group vitamin and body height, body weight, body mass index, body surface area, urine volume, and urinary creatinine were determined. Only urinary vitamin B(12) was strongly correlated to urine volume in young (r = 0.683, P < .001) and elderly (r = 0.523, P < .001) subjects. To confirm this finding, 20 Japanese adults were orally administered 1.5 mg of cyanocobalamin (500-fold higher daily intake); and correlations between urinary vitamin B(12) and urine volume were determined. The load of cyanocobalamin increased vitamin B(12) content in the urine by only 1.3-fold. Urinary vitamin B(12) was strongly correlated with urine volume on the day before taking, the day of taking, and the day after taking cyanocobalamin (r = 0.745, P < .001; r = 0.897, P < .0001; and r = 0.855, P < .0001, respectively). We conclude that urinary excretion of vitamin B(12) is dependent upon urine volume, but not on intake of vitamin B(12). Physical characteristics and urine volume are less important for B-group vitamins except for vitamin B(12) as biomarker.

Intra- and Inter-Individual Variations of Blood and Urinary Water-Soluble Vitamins in Japanese Young Adults Consuming a Semi-Purified Diet for 7 Days

We have previously reported the levels of water-soluble vitamins in the blood and urine of Japanese young adults. In the present paper, to assess the variations in these water-soluble vitamin markers during the above experiment, we comprehensively determined the intra- and inter-individual variations of blood and urinary water-soluble vitamins to exactly the same amount of water-soluble vitamin intakes in the same experiment. The blood samples before breakfast and the 24-h urine samples were periodically collected from Japanese college male (n=10) and female (n=10) students consuming a semi-purified diet with water-soluble vitamins based on Japanese Dietary Reference Intakes for 7 d, and the intra- and inter-individual variations of blood and urinary water-soluble vitamins or their metabolites in blood and urine samples after adaptation were calculated. Although urinary excretion of vitamin B(12) and vitamin C showed high intra-individual variations in both males and females, other urinary vitamins and all blood vitamins showed less than 20% of within-subject coefficients of variance in either male or female. Those showing more than 20% of between-subject coefficients of variances in both male and female were blood vitamin B(6), vitamin B(12) and folate levels, and urinary vitamin B(1), vitamin B(2), vitamin B(12), nicotinamide metabolites, pantothenic acid, biotin and vitamin C. These results showed that oral administration of constant of water-soluble vitamins generally decreased intra-individual variation, while individual differences in urinary vitamin excretion were observed.

The effect of vitamin C supplementation on plasma concentration and urinary excretion of vitamin C in cattle

We investigated the plasma concentration and urinary excretion of vitamin C in cows supplemented with vitamin C. Five cows (mean BW = 597 kg) were allocated to a 5 x 5 Latin square design and supplemented with a vitamin C preparation coated with hydrogenated soybean oil at 0, 10, 20, 40, or 60 mg of vitamin C per kg of BW per day for 9 d. Plasma and urine samples were collected for measuring vitamin C concentration. Urinary excretion of vitamin C was expressed as the ratio of vitamin C to creatinine. Plasma vitamin C concentration and urinary vitamin C excretion increased quadratically as dietary vitamin C increased (P < 0.001); that is, the lowest dose affected neither plasma vitamin C concentration nor urinary vitamin C excretion but the plasma vitamin C concentration and urinary vitamin C excretion increased (P < 0.05) with increasing supplementation of vitamin C at greater doses. This suggests that plasma vitamin C concentration affects urinary excretion of vitamin C in cattle and that plasma vitamin C concentration exceeded the renal threshold for vitamin C in the cows receiving vitamin C at 20 mg/kg of BW per day. Furthermore, increased urinary excretion of vitamin C appears to limit plasma vitamin C concentration in response to vitamin C intake. The daily excretion of vitamin C was estimated by the reported value of daily creatinine excretion, indicating that the daily amount of vitamin C excreted into urine was more than half of supplied vitamin C. Therefore, a large part of supplied vitamin C probably escapes ruminal degradation and is absorbed but excreted into urine.

Excretion of the Urinary 5C- and 7C-Aglycone Metabolites of Vitamin K by Young Adults Responds to Changes in Dietary Phylloquinone and Dihydrophylloquinone Intakes

The physiological function and putative health roles of vitamin K-dependent proteins now extend beyond their classical role in hemostasis and include bone mineralization, arterial calcification, apoptosis, phagocytosis, growth control, chemotaxis, and signal transduction. Current assessments of vitamin K status do not reflect the variety of molecular forms of vitamin K. We assessed whether urinary excretion of 2-methyl-3-(5´-carboxy-3´-methyl-2´-pentenyl)-1,4-naphthoquinone (7C-aglycone) and 2-methyl-3-(3´-3´-carboxymethylpropyl)-1,4-naphthoquinone (5C-aglycone), vitamin K metabolites common to both phylloquinone and the menaquinone series, reflect dietary vitamin K intake. In a randomized crossover study, 9 adults resided in a metabolic unit for two 30-d periods separated by a free-living period of ≥4 wk. During each residency, subjects consumed 3 sequential diets: a control diet (93 μg phylloquinone/d) for 5 d, a phylloquinone-restricted diet (11 μg/d) for 15 d, followed by a randomly assigned repletion diet for 10 d with either phylloquinone (206 μg/d) or dihydrophylloquinone (240 μg/d). During the second residency, the alternative repletion diet was assigned. Urinary excretion of the 5C- and 7C-aglycones was measured in sequential 24-h collections. The 5C-aglycone accounted for ∼75% of total excretion and declined in response to phylloquinone restriction (P = 0.001) to ∼30% of that during the control diet period. Repletion with phylloquinone and dihydrophylloquinone doubled the excretion rate of the major 5C-aglycone by 24 h (P < 0.001), and tripled excretion by 4 d. There was a linear relationship between the logarithm of total urinary excretion and dietary vitamin K intake (r = 0.699, P < 0.001). We conclude that the urinary excretion of vitamin K metabolites reflects dietary phylloquinone intake and offers the first candidate marker of global vitamin K status.

Urinary excretion of Vitamin C among urban college students

Urinary excretion of Vitamin C among urban college students

Comparison of the Effects of Di(2-ethylhexyl)phthalate, a Peroxisome Proliferator, on the Vitamin Metabolism Involved in the Energy Formation in Rats Fed with a Casein or Gluten Diet

In order to find an alleviation method for the adverse effect of environmental endocrine disrupters, we studied the effects of the putative endocrine disrupter and peroxisome proliferator, di(2-ethylhexyl)phthalate (DEHP), on animal growth and vitamin metabolism. It is known that the effects of chemical compounds such as xenobiotics differ according to the dietary protein source. We compared the effects of dietary DEHP administration on rats fed with a diet containing milk casein or wheat gluten. The increased conversion ratio of tryptophan to nicotinamide by DEHP administration was significantly higher in the casein group than in the gluten group. We also investigated the effects of DEHP on the urinary excretion of other vitamins. DEHP administration resulted in decreased urinary excretion of vitamin B(1), vitamin B(2), and pantothenic acid.

Requirement and criteria of adequate vitamin supply in healthy newborns.

Studies of the relationship between urinary excretion of vitamins and their daily intake in healthy newborns showed that babies aged 3-10 days should receive 30 mg vitamin C, 0.24 mg vitamin B(2), and 0.13 mg vitamin B(1). The criteria of adequate vitamin C, B(1), and B(2) supply evaluated by their urinary excretion are 220.0, 0.7, and 1.4 mg/g excreted creatinine, respectively.

Urinary Excretion of Vitamin A in Critically Ill Patients Complicated with Acute Renal Failure

Objective. Study the possible excretion of vitamin A in urine of critically ill patients complicated with acute renal failure. Patients and Methods. Nine Intensive z`Care Unit patients, age 71.2 ± 15.7 (mean ± SD) with acute renal failure were studied. Urinary retinol, creatinine, protein, albumin, and serum creatinine were measured. Results. All patients excreted retinol in urine; individual values ranged from 0.007 to 0.379 µmol retinol/mmol creatinine. There was no correlation of urinary retinol/creatinine ratio with serum creatinine or with urinary protein/creatinine and albumin/creatinine ratios. Conclusion. Excretion of retinol in urine may be indicative of acute renal failure in critically ill patients.