Influence of Glucose Dosage in Parenteral Nutrition on Body Thiamine Levels in Rats.

The objective of this study was to determine the relationship between glucose dosage in parenteral nutrition and reductions in levels of body thiamine in rats. Vitamin-free infusions with differing amounts of glucose were administered to normal or thiamine-deficient rats for 5 days, after which urinary thiamine excretion and the amounts of thiamine in the blood, liver, brain, and skeletal muscles were measured. The total energy dosage was set at three levels (98, 140, and 196 kcal/kg), and the dose of amino acids was constant among all groups. Urinary thiamine excretions on Day 5 decreased with increasing glucose dosage in the infusions. In normal rats, the amount of thiamine in the blood and all organs decreased compared with the diet group; however, no significant differences were found among the infusion groups. In thiamine-deficient rats, on the other hand, the amount of thiamine in the liver and skeletal muscles did not differ significantly among infusion groups; however, the amount of thiamine in the brain and blood decreased with increasing glucose dosage. An organ-specific correlation was found between glucose dosage in infusions and reductions in levels of thiamine. To prevent thiamine deficiencies from affecting the central nervous system, greater caution must be exercised during high-caloric parenteral nutrition. However, a constant supply of thiamine seemed to be essential, irrespective of the amount of energy supplied via parenteral nutrition, to maintain a sufficient level of thiamine in the body.

Recent trends in determination of thiamine and its derivatives in clinical practice.

Over the last five decades, many methods to analyze thiamine (vitamin B1) and its phosphorylated forms in urine, whole blood, serum, plasma and erythrocytes have been proposed. Some of the methods are presently used in routine practice, but analytical problems regarding reproducibility, standardization, lack of automation, time consuming procedures for pretreatment and analysis are often discussed. With modern approaches to bioanalysis in clinical research of vitamins, whole processes can be automated, making analysis less time consuming, with reduced consumption of solvents and samples. This review critically discusses various analytical techniques, their advantages and disadvantages that are used for determination of thiamine and its derivatives in clinical practice, with emphasis on accurate, reliable and fast analytical procedures.

High-performance liquid chromatographic method for profiling 2-oxo acids in urine and its application in evaluating vitamin status in rats.

B-group vitamins are involved in the catabolism of 2-oxo acids. To identify the functional biomarkers of B-group vitamins, we developed a high-performance liquid chromatographic method for profiling 2-oxo acids in urine and applied this method to urine samples from rats deficient in vitamins B1 and B6 and pantothenic acid. 2-Oxo acids were reacted with 1,2-diamino-4,5-methylenebenzene to produce fluorescent derivatives, which were then separated using a TSKgel ODS-80Ts column with 30 mmol/L of KH2PO4 (pH 3.0):acetonitrile (7:3) at a flow rate of 1.0 mL/min. Vitamin B1 deficiency increased urinary levels of all 2-oxo acids, while vitamin B6 deficiency only increased levels of sum of 2-oxaloacetic acid and pyruvic acid, and pantothenic acid deficiency only increased levels of 2-oxoisovaleric acid. Profiles of 2-oxo acids in urine samples might be a non-invasive way of clarifying the functional biomarker of B-group vitamins.

Effects of Fatty Liver Induced by Excess Orotic Acid on B-Group Vitamin Concentrations of Liver, Blood, and Urine in Rats.

Fatty liver is caused when rats are given orotic acid of the pyrimidine base in large quantities. The lack of B-group vitamins suppresses the biosynthesis of fatty acids. We investigated how orotic acid-induced fatty liver affects the concentrations of liver, blood, and urine B-group vitamins in rats. The vitamin B6 and B12 concentrations of liver, blood, and urine were not affected by orotic acid-induced fatty liver. Vitamin B2 was measured only in the urine, but was unchanged. The liver, blood, and urine concentrations of niacin and its metabolites fell dramatically. Niacin and its metabolites in the liver, blood, and urine were affected as expected. Although the concentrations of vitamin B1, pantothenic acid, folate, and biotin in liver and blood were decreased by orotic acid-induced fatty liver, these urinary excretion amounts showed a specific pattern toward increase. Generally, as for the typical urinary excretion of B-group vitamins, these are excreted when the body is saturated. However, the ability to sustain vitamin B1, pantothenic acid, folate, and biotin decreased in fatty liver, which is hypothesized as a specific phenomenon. This metabolic response might occur to prevent an abnormally increased biosynthesis of fatty acids by orotic acid.

Glutathione-stabilized Cu nanoclusters as fluorescent probes for sensing pH and vitamin B1.

Glutathione (GSH), playing roles as both a reducing reagent and protecting ligand, has been successfully employed for synthesizing Cu nanoclusters (CuNCs@GSH) on the basis of a simple and facile approach. The as-prepared CuNCs exhibited a fluorescence emission at 600nm with a quantum yield (QY) of approximately 3.6%. Subsequently, the CuNCs described here was employed as a broad-range pH sensor by virtue of the fluorescence intensity of CuNCs responding sensitively to pH fluctuating in a linear range of 4.0-12.0. Meanwhile, these prepared CuNCs were applied for detections of vitamin B1 (VB1) on the basis of positively charged VB1 neutralizing the negative surface charge of CuNCs, thus leading to the instability and aggregations of CuNCs, and further facilitating to quench their fluorescence. In addition, the proposed analytical method permitted detecting VB1 with a linear range of 2.0×10(-8)-1.0×10(-4) mol L(-1) as well as a detection limit of 4.6×10(-9) mol L(-1). Eventually, the practicability of this sensing approach was validated by assaying VB1 in human urine samples and pharmaceutical tablets, confirming its potential to broaden avenues for assaying VB1.

[Evaluation of sufficiency with vitamins C, B1 and B2 of newborn infants feeding different types of nutrition, by means of urinary excretion determination].

With the help of non-invasive methods the sufficiency with vitamins C, B1 and B2 in 58 newborns (38-40 weeks of gestation) on breastfeeding as well as on mixed or artificial feeding has been evaluated. Urinary excretion and breast content of ascorbic acid (measured by visual titration), thiamin (by thiochrome fluorimetric method) andriboflavin (fluorimetrically by titration with riboflavin-binding protein) was determined on the 3-10th day after birth. 35 infants were exclusively breastfed. 40% of their mothers regularly took multivitamin supplements during pregnancy and 42.9%--both during pregnancy and after childbirth, 17.1% did not use vitamin complexes either duringpregnancy or after childbearing. The content of vitamins C, B1 and B2 in the breast milk of women who did not additionally intake vitamins during pregnancy and lactation, was reduced compared with that of mothers who took multivitamin supplements, and provided only a half of the needs of their child in these vitamins. All these babies have urinary excretion of vitamins below the lower limit of norm. Among infants whose mothers took multivitamin supplements during pregnancy, but stop taking them immediately after their birth, only 28.6% of newborns were provided with vitamin C, while all the children identified a lack of vitamins By and B2. The insufficiency with vitamins C and B1 was detected in one third of children breastfed by mothers who took vitamins during pregnancy and continued intaking them after birth, adequate supplied with vitamin B2 was 35.7% of the surveyed. Determination of vitamin urinary excretion (perg creatinine) is useful for vitamin status evaluation. The content of vitamins in breast milk can be used for assessment of vitamin status both a nursing woman and her child. Taking into consideration that the diet of a breastfeeding woman is not always the best, there is no doubt about the need to continue multivitamin intake during breastfeeding. The question on the doses of vitamins in vitamin-mineral supplements for lactating women, providing vitamin content of breast milk at an optimal level, or intended specifically for infants, nowadays is extensively discussed.

A sensitive fluorescent assay for thiamine based on metal-organic frameworks with intrinsic peroxidase-like activity.

Metal-organic frameworks (MOFs) with tunable structures and properties have recently been emerged as very interesting functional materials. However, the catalytic properties of MOFs as enzymatic mimics remain to be further investigated. In this work, we for the first time demonstrated the peroxidase-like activity of copper-based MOFs (HKUST-1) by employing thiamine (TH) as a peroxidase substrate. In the presence of H2O2, HKUST-1 can catalyze efficiently the conversion of non-fluorescent TH to strong fluorescent thiochrome. The catalytic activity of HKUST-1 is highly dependent on the temperature, pH and H2O2 concentrations. As a peroxidase mimic, HKUST-1 not only has the features of low cost, high stability and easy preparation, but also follows Michaelis-Menten behaviors and shows stronger affinity to TH than horseradish peroxidase (HRP). Based on the peroxidase-like activity of HKUST-1, a simple and sensitive fluorescent method for TH detection has been developed. As low as 1 µM TH can be detected with a linear range from 4 to 700 µM. The detection limit for TH is about 50 fold lower than that of HRP-based fluorescent assay. The proposed method was successfully applied to detect TH in tablets and urine samples and showed a satisfactory result. We believed that the present work could improve the understanding of catalytic behaviors of MOFs as enzymatic mimics and find out a wider application in bioanalysis.

[Imbalance of microelements and vitamins in adolescents with diffuse nontoxic goiter and biliary dyskinesia].

The purpose of the present work was to study the level of microelements and vitamins in adolescents with diffuse nontoxic goiter. It has been shown that comorbid biliary dyskinesia leads to significant dysregulation of vitamin and mineral metabolism: the level of essential elements was decreased and the level of toxic elements was increased. Comorbid biliary dyskinesia in adolescents with diffuse nontoxic goiter was accompanied by a disbalance of vitamins. The changes found in micronutrients have sex differences.

The body vitamin B1 levels of rats fed a diet containing the minimum requirement of vitamin B1 is reduced by exercise.

It is thought that increasing energy expenditure increases consumption of vitamin B1, leading to an increase in the requirement of vitamin B1. However, evidence supporting this hypothesis is lacking. To examine the hypothesis, initially, we determined the minimum requirement of vitamin B1 for weaning rats. We found that the minimum requirement of vitamin B1 for optimum growth of weaning rats was around 0.786 mg thiamin/kg diet. Next, rats fed a diet containing the minimum requirement of vitamin B1 were forced to swim until exhaustion. Concentrations of vitamin B1 in the blood and liver as well as urinary excretion of swimming rats decreased significantly compared with those of non-swimming rats (p<0.05), while in rats fed the diet containing a sufficient amount of vitamin B1 (4.720 mg thiamin/kg diet), vitamin B1 amounts in the blood, liver and urine were not affected by swimming. We clearly and firstly showed the reduction of body vitamin B1 following increases in energy expenditure.

[Investigation of vitamin B1, vitamin B2 and niacin levels among children aged 0-3 years old in Chinese urban and rural areas].

OBJECTIVE: To study the nutritional status and differences in vitamin B1, vitamin B2, and niacin of the urban/rural infants in Shandong Province, and to provide scientific basis for infants nutrition interventions. METHODS: 106 urban infants and 290 rural infants were selected from a city in Shandong Province. Forty milliliter urinary was collected from each one, which was adjusted to pH 4-5 with concentrated hydrochloric acid immediately. The concentration of thiamine, riboflavin and niacin in the urine was detected by fluorescence method. RESULTS: The insufficient percentages of vitamin B, vitamin B2 and niacin in urban infants were 1.9%, 8.0% and 9.1%, and that in rural infants were 4.5%, 56.7% and 27.1%. The median concentrations of vitamin B1 in urban and rural infants were 495.00 and 420.56 microg/g respectively, in which the 12-month and 24-month groups in urban were higher than that in rural (P<0.05). The medians of vitamin B2 content in urban and rural infants were 303.07 and 70.88 microg/g, and the content of vitamin B2 in urban infants was higher than that in rural infants in each group (P<0.05). The median concentrations of niacin content in urban and rural infants were 6.31 and 4.22 microg/g, and the niacin content of 6month-, 12 month-, 18 month- and 24 month- groups in urban infants were higher than that in rural infants (P<0.05). CONCLUSION: There were significant differences in vitamin B1, B2 and niacin content of infants between urban and rural areas, and the nutriture of urban infants was better than the rural infants. More improvement measures should be given to infants in rural areas for the high proportion of vitamin B, and niacin deficiency.

Thiamine supplementation in symptomatic chronic heart failure: a randomized, double-blind, placebo-controlled, cross-over pilot study.

BACKGROUND: Diuretic treatment for heart failure may lead to an increased urinary thiamine excretion and in long-term thiamine deficiency, which may further compromise cardiac function. This study evaluated the effect of high dose thiamine supplementation in heart failure patients. METHODS: Nine patients with diuretic treatment for symptomatic chronic heart failure and a left ventricular ejection fraction (LVEF) <40% were randomly assigned to receive thiamine (300 mg/day) or placebo for 28 days. After a wash-out of 6 weeks, the patients crossed-over to a second treatment period. The primary outcome was a change in LVEF. RESULTS: Mean age was 56.7 ± 9.2 years (range 44.9-75.4 years). Baseline LVEF was similar for both treatment groups (29.5% in the thiamine group and 29.5% in the placebo group, P = 0.911). After 28 days of thiamine treatment, the LVEF increased to 32.8% which was significantly (P = 0.024) different from the LVEF in the placebo group (28.8%). This corresponds to a treatment effect for LVEF of 3.9% in absolute terms. CONCLUSIONS: This study suggests that thiamine supplementation has beneficial effects on cardiac function in patients with diuretic drugs for symptomatic chronic heart failure. Subclinical thiamine deficiency is probably an underestimated issue in these outpatients.

[Characteristics of nutrition and vitamin supply in girls with metabolic syndrome].

Assessment of actual nutrition in girls with metabolic syndrome revealed excess dietary energy value due to the higher intake of fat and carbohydrates (mono- and disaccharides in particular) and the low intake of vitamin E. The vitamin status of the majority of girls with metabolic syndrome showed varying blood and urinary vitamin E, C, and B, deficiencies.

Patients with gastrointestinal tract disorders receiving parenteral nutrition need a higher dose of vitamin C.

BACKGROUND/AIMS: Appropriateness of the vitamin doses in Japanese commercial multi-vitamin preparations for parenteral nutrition therapy was investigated in patients with gastrointestinal tract disorder by evaluating the vitamin status (blood concentrations and urinary excretions of vitamins B1, B2, B6, and C) of them. METHODOLOGY: Commercial multivitamin preparations were administered continuously with a commercial PN solution over 5 days to 10 patients with gastrointestinal tract disorder. Blood concentrations of vitamins B1, B2, B6, and C were measured on the mornings of day 1, day 4, and day 6. Urinary excretions were measured in 24-h urine collections collected after day 3 and after day 5. RESULTS: Blood concentrations of vitamins B1, B2, and B6 increased but remained within or slightly above the normal throughout the study, and urinary excretion values were normal in all patients. However, blood vitamin C concentration surpassed the lower limit of normal (5.5 microg/mL) only on day 6. Urinary vitamin C excretion was below normal (20.0 mg/day) in all and 7 patients on days 3 and 5, respectively. CONCLUSIONS: In patients with gastrointestinal tract disorder, the doses of vitamins B1, B2, and B6 of Japanese commercial multi-vitamin preparations are adequate but that of vitamin C (100 mg/day) is inadequate and should be increased.

[Influence wheat bran on organism vitamin (experiment on rats)].

The inclusion of wheat bran (at a dose of 2,3 and 4,6% of the dry weight) in the semi-synthetic diet of rats under combined deficiency of vitamins (20 and 50% of the adequate level) did not have a significant effect on vitamins C, B1 and B2 liver levels, riboflavin blood plasma level, and thiamine and riboflavin urinary excretion. The consumption of bran in high dose has been accompanied by a decrease of retinol blood plasma level on 19-28% but it has no effect on liver retinol palmitate content. Bran intake in both doses resulted in a deterioration of rats sufficiency with vitamin E, which had been confirmed by a simultaneous significant decrease of blood plasma alpha-tocopherol concentration on 31-40%, and its liver level on 23-43%. The results obtained indicate the advisability of vitamin E enrichment of diets with a high content of dietary fiber.

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.

Sulbutiamine in sports.

Sulbutiamine (isobutyryl thiamine disulfide) is a lipophilic derivative of thiamine used for the treatment of asthenia and other related pathological conditions. It is available over-the-counter in several countries either as a component of nutritional supplements or as a pharmaceutical preparation. The presence of sulbutiamine in urinary doping control samples was monitored to evaluate the relevance of its use in sports. As one of the sulbutiamine metabolites has very close retention time and the same characteristic ion (m/z 194) as the main boldenone metabolite, the raw data files generated from the screening for anabolic steroids were automatically reprocessed to identify the samples containing sulbutiamine. It was found that of ca. 16 000 samples analyzed in the Russian laboratory during 2009, about 100 samples contained sulbutiamine. It is important to note that most of these samples were collected in-competition, and sulbutiamine concentration was estimated to be greater than 500 ng/ml. This may indicate that sulbutiamine was intentionally administered for its ergogenic and mild stimulating properties.

A capillary zone electrophoretic method for simultaneous determination of seven drugs in pharmaceuticals and in human urine.

A simple, sensitive, and novel method has been developed and validated for the separation and simultaneous quantitation of seven structurally different drugs-pipemidic acid and ofloxacin quinolone antibiotics, pseudoephedrine decongestant, piroxicam anti-inflammatory, thiamin, pyridoxine, and cobalamin-in a mixture by capillary zone electrophoresis. Factors affecting the separation were pH, concentration of buffer, and applied voltage. Separation was carried out in < 9 min with a 50 mM sodium tetraborate buffer, pH 10, and an applied voltage of 30 kV in an uncoated silica capillary tube. The carrier electrolyte gave baseline separation with good resolution, reproducibility, and accuracy. Calibration plots were linear over at least three orders of magnitude of analyte concentrations, and the lower LODs were within the range of 1-5 microg/mL. Detection was performed by UV absorbance at 230 nm. The method was validated for the analysis of drugs in pharmaceutical preparations and in urine samples with RSD of 0.5-2.4% and recovery of > 99%.

High-dose thiamine therapy for patients with type 2 diabetes and microalbuminuria: a randomised, double-blind placebo-controlled pilot study.

AIMS/HYPOTHESIS: High-dose supplements of thiamine prevent the development of microalbuminuria in experimental diabetes. The aim of this pilot study was to assess whether oral supplements of thiamine could reverse microalbuminuria in patients with type 2 diabetes. METHODS: Type 2 diabetic patients (21 male, 19 female) with microalbuminuria were recruited at the Diabetes Clinic, Sheikh Zayed Hospital, Lahore, Pakistan, and randomised to placebo and treatment arms. Randomisation was by central office in sequentially numbered opaque, sealed envelopes. Participants, caregivers and those assessing the outcomes were blinded to group assignment. Patients were given 3 x 100 mg capsules of thiamine or placebo per day for 3 months with a 2 month follow-up washout period. The primary endpoint was change in urinary albumin excretion (UAE). Other markers of renal and vascular dysfunction and plasma concentrations of thiamine were determined. RESULTS: UAE was decreased in patients receiving thiamine therapy for 3 months with respect to baseline (median -17.7 mg/24 h; p < 0.001, n = 20). There was no significant decrease in UAE in patients receiving placebo after 3 months of therapy (n = 20). UAE was significantly lower in patients who had received thiamine therapy compared with those who had received placebo (30.1 vs 35.5 mg/24 h, p < 0.01) but not at baseline. UAE continued to decrease in the 2 month washout period in both groups, but not significantly. There was no effect of thiamine treatment on glycaemic control, dyslipidaemia or BP. There were no adverse effects of therapy. CONCLUSIONS/INTERPRETATION: In this pilot study, high-dose thiamine therapy produced a regression of UAE in type 2 diabetic patients with microalbuminuria. Thiamine supplements at high dose may provide improved therapy for early-stage diabetic nephropathy. TRIAL REGISTRATION: CTRI (India) CTRI/2008/091/000112. FUNDING: Pakistan Higher Education Commission.

Estimation of vitamin B1 excretion in 24-hr urine by assay of first-morning urine.

Urinary B1 (vitamin B1) excretion is commonly determined in 24-hr urine specimens to obtain an estimate of nutritional status. The aim of our study was to investigate whether B1 in random urine specimens, corrected for the urine creatinine (Cr), can be substituted for B1 in 24-hr urines. Collection of such hour urines is often fraught with errors; an alternative method is described here. All urine specimens voided over 24 hr were collected from 32 healthy adults as were the first-morning urines from 30 healthy Japanese women. The B1 excretion was expressed as the ratio of B1 to Cr. Although the B1 excretion was expressed as the B1/Cr ratio, the B1 excretion varied with the urine volume and the time of urine collection. The B1/Cr ratio in random urine specimens not collected at a fixed time may mislead the evaluation of the nutritional status. We found that the B1/Cr ratio in the first-morning urine correlated significantly with the ratio in 24-hr urines (r=0.970, P<0.001) and also with the concentration of total B1 (B1 plus its phosphate esters) in whole blood (r=0.733, P<0.001). We conclude that the B1/Cr ratio in 24-hr urines could be estimated by measuring the ratio in the first-morning urine.