We examined the effect of vitamin K and vitamin D supplementation on cah cium balance in young rats fed a normal or low calcium diet. Eighty female Sprague Dawley rats, 6 wk of age, were randomized by the stratified weight method into eight groups with 10 rats in each group: 0.5% (normal) or 0.1% (low) calcium diet, 0.5% or 0.1% calcium diet+vitamin K (vitamin K2, menatetrenone, 30 mg/100 g, food intake), 0.5% or 0.1% calcium diet+vitamin D (25μg/100g, food intake), and 0.5% or 0.1% calcium diet+vitamin K+vitamin D. The duration of the study was 10 wk. Vitamin K supplementation promoted the reduction in urinary calcium excretion and retarded the abnormal elevation of serum PTH level in rats fed a low calcium diet, and stimulated intestinal calcium absorption in rats fed a normal calcium diet. Vitamin D supplementation stimulated intestinal calcium absorption with prevention of the abnormal elevation of serum PTH levels and prevented hypocalcemia in rats fed a low calcium diet, and stimulated intestinal calcium absorption in rats fed a normal calcium diet. The stimulation of intestinal calcium absorption was associated with increased serum 1, 25-dihydroxyvitmain D levels. An additive effect of vitamin K and vitamin D on intestinal calcium absorption was found only in rats fed a normal calcium diet. This study shows the differential effects of vitamin K and vitamin D supplementation on calcium balance in young rats fed a normal or low calcium diet.

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This study determines the effect of lysophosphatidylcholine (lysoPC) and phosphatidylcholine (PC) in mixed micelles on β-carotene and retinyl palmitate levels in rats in order to delineate the role of micellar phospholipids in the intestinal uptake of β-carotene and its conversion into vitamin A. The rats were fed a single dose of β-carotene solubilized in lysoPC (LPC group), PC (PC group) or no phospholipids (NoPL, control group) in micellar form. The level of β-carotene and retinyl palmitate in plasma and β-carotene in liver was analyzed by HPLC after 1, 2, 3, 6 and 9 h of feeding. The postprandial levels of β-carotene in plasma (599.9 pmol/mL, Area Under Curve (AUC)) and in liver (1, 161.3 pmol/g) were significantly (p<0, 05) higher in the LPC group compared with its level in plasma (207.2 pmol/ mL) and in liver (6 16.5 pmol/g) of the PC group and in plasma (119.1 pmol/mL) and in liver (626.2 pmol/g) of the NoPL group. No difference was seen between the PC and NoPL groups. The results demonstrate that β-carotene absorption and its accumulation in plasma and liver were unaffected by PC compared with NoPL, while lysoPC not only enhanced its accumulation but also increased cleavage of intestinally absorbed β-carotene into vitamin A as the AUC of plasma BC was higher and the AUC of retinyl palmitate in plasma of the lysoPC group was significantly higher than those of the other two groups. The results suggest that the luminal hydrolysis of PC to lysoPC is necessary for intestinal uptake of β-carotene solubilized in mixed micelles.

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We have previously reported that dietary sesame lignan elevates α-tocopherol concentration and decreases lipid peroxidation in tissues and serum of rats fed α-tocopherol. In this study, the effect of dietary sesame seeds on α-tocopherol concentration and lipid per-oxidation in rat brain was examined. In experiment 1, male Wistar rats (4 wk old) were fed a vitamin E-free diet, or a diet containing α-tocopherol with or without sesame seeds for 1, 4 and 8 wk. The dietary sesame seeds elevated the αa-tocopherol and lowered the thiobarbituric acid-reactive substance (TBARS) concentrations in the brain of the rats fed α-tocopherol for 4 and 8 wk. The dietary sesame seeds maintained the high α-tocopherol concentration in the brain during the experimental period, while the concentration of the rats fed α-tocopherol without sesame seeds was lowered after 8 wk. Then, the α-tocopherol concentration in various regions of the brain of rats fed a basal level of α-tocopherol with sesame seeds was compared with that . of rats fed an excess amount of α-tocopherol in experiment 2. The a-tocopherol concentration in the cerebrum, cerebellum, brain stem and hippocampus of, the rats fed 50mg α-tocopherol/kg with sesame seeds was higher than those of the rats fed 500mg α-tocopherol/kg without sesame seeds. These results suggest that the dietary sesame seeds are more useful than the intake of an excess amount of α-tocopherol, for maintaining a high, α-tocopherol concentration and inhibiting lipid peroxidation in the various regions of the rat brain.

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There is scarce information on the relative importance of socioeconomic factors in determining the adolescent anthropometric measurements. The objective of this study was to examine the effects of economic status, education level, and food consumption on the height and weight of community adolescents in Nepal. The study was done in the communities of the Kathmandu Valley area in Nepal. All together 42 6 unmarried adolescent girls aged 14-19 y were selected, The adolescents were interviewed regarding socioeconomic background (education, occupation and property possessions) and frequency of foods consumption. Height and weight were determined and BMI was calculated. Z-scores of height-for-age and weight-for-age were calculated based on the WHO/NCHS standard to avoid bias by age. The adolescents participating in the survey were categorized into three groups using the various indicators of economic status: Low Economic Status (LES) group, Middle Economic Status (MES) group and High Economic Status (HES) group. The Z-scores of height and weight were significantly lower in the LES group than in the MES and HES groups (p<0.05). The Z-score of height was significantly increased with education level even under the condition of controlling economic level (p<0.05). Since the frequency of milk consumption was significantly related not only with height (p<0.05), but also with economic (X²=3 df=4, p<0.001) and education levels (X²=22.4, df=6, p<0.01), the increased height in the groups of the better economic status or the better education level was interpreted to be due to the outcome of the higher frequency of milk consumption. This study indicated that education was a more important factor affecting the height of the adolescents via improved food habits even under adverse economic conditions.

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To determine the concentrations of fat-soluble and water-soluble vitamins in the maternal milk of Japanese women, we collected human milk samples from more than 4, 000 mothers living throughout Japan between December 1998 and September 1999, and defined as group A the 691 samples among these that met the following conditions: breast milk of mothers who were under 40 y of age, who did not smoke habitually and/or use vitamin supplements, and whose babies showed no symptoms of atopy and had birth weights of 2.5kg or more. We then analyzed the contents of vitamins individually. Large differences were observed among the contents of individual human milk samples. The mean contents of each component were as follows: vitamin A, 159.0±95.2 IU/ 100 mL; vitamin E, 0.325±0.165 α-TE mg/ 100 mL; vitamin D₃ (cholecalciferol), 8.0±10.7 ng/100mL; vitamin B₁ (thiamin), 12.3±3.2μg/100mL; vitamin B₂, 38.4±12.7μg/100mL; vitamin B₆, 5.7±2.5μg/100mL; vitamin B₁₂, 0.04±0.02μg/100mL; vitamin C, 5.1±1.9mg/100mL; biotin, 0.5 0±0.23μg/100mL; choline, 9.2±1.8mg/100mL; folic acid, 6.2±2.9μg/100mL; inositol, 12.6±3.6mg/100mL; niacin (nicotinamide), 32.9±20.4μg/100mL and pantothenic acid, 0.27±0.09mg/100mL. The concentrations of derivatives and/or related compounds of vitamin A (retinol, β-carotene), vitamin E (α-, β-, γ-, and δ-tocopherol), and B₂ (riboflavin, FMN, and FAD) were determined separately. The contents of each were found to vary greatly as the duration of lactation increased. The present results indicate that it is necessary to evaluate individual differences in human milk in order to perform valid research regarding infant formula.

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This experiment was conducted to study the effects of fasting and refeeding on proteolytic-related gene expression in skeletal muscles of chicks. Chicks were fasted for 24h, and refed for h. Plasma N^τ-methylhistidine concentration, as an index of myofibrillar protein degradation, was increased by fasting, and that increment was reduced by refeeding. We also examined the expression of the protease mRNAs (calpain, proteasome, cathepsin and caspase-3) by real-time PCR of cDNA in skeletal muscles of fasting and refeeding chicks. Calpain (m-, μ-, and p94/calpain-3) mRNA expressions were also increased by fasting, and their increment was reduced by refeeding. Ubiquitin and 20S proteasome α subunit (α6 and α7) mRNA expressions as well as cathepsin B, and caspase-3 mRNA expression were likewise increased by fasting, with their increment also reduced by refeeding. These results indicate that fasting stimulates proteolytic-related gene expression, resulting in an increase in myofibrillar protein degradation, and that refeeding suppresses proteolytic-related gene expression, resulting in a decrease in myofibrillar protein degradation in chicks.

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The aim of this study was to investigate the protective effect of Isoflavone against hypertension, via the mitigation of oxidative stress and prevention of nitric oxide (NO, a potent vasodilator) reduction, in spontaneously hypertensive rats (SHR). The 8 wkold male SHR were divided into two groups, and fed a casein-based high fat diet (120g fat, 1 g cholesterol/kg diet) for 30 d, either with or without 10 g of soy powder (containing 31.2% of Isoflavones)/kg. During the 30-d study period, tail systolic blood pressures (BP) in the control SHR group increased, from 162.4±2.3 to 177, 9±5.4 mmHg (p<0.05), while the Isoflavone-supplemented group benefited from a clear antihypertensive effect (160.1±1.8 to 160.2±4.9mmHg). The serum NO and total radical trapping antioxidant potential (TRAP) were elevated in the Isoflavone group. The isoflavone group also experienced a significant decrease in oxidative DNA damage in leukocytes, using comet assay. DNA damage correlated positively with incremental BP during the study, and systolic BP at the end of the study (p<0.01). Our results indicate that soy isoflavone has an antihypertensive effect, possibly through the amelioration of oxidative stress, and the augmentation of NO production, in SHR.

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The Japanese school lunch system, which has over 100 y of history, has gained world attention for its well-developed and steady system, healthy Japanese-style menus including rice, and educational programs utilizing the school lunch system. Meanwhile, risk factors of health among students have been continuously worsening for the past dozen years or so. Therefore, Japan had hastened to develop better educational programs utilizing the school lunch and nutritional teachers. Under such circumstances, the Japanese Diet passed a bill to amend the School Education Law (hereinafter called the Amendment) which includes the establishment of an educational system by nutrition teachers in May, 2004. This system will be enforced in April, 2005. This system by nutrition teachers in Japan is well organized in both the legal and administrative senses and is attracting domestic and international attention as an example of an educational measure to improve the dietary life of students. The reason for this article in English is the additional intention of enlightening other countries by showing the political promotion problems of educational administration agencies, educational contents of nutrition teachers and some issues of the new educational system by nutrition teachers.

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The content of calcium (Ca) and magnesium (Mg) in sweat during exercise is considerably higher during a relatively low intake of sodium (Na) of 100 mmol/d than with an intake of 170 mmol/d. For this reason and also because Ca and Mg have a negative bal ance with a Na intake of 100 mmol/d, we analyzed the relationship between Na intake and balances of Ca and Mg in data from 11 balance studies. From 1986 to 2000, 109 volunteers (23 males, 8 6 females) with an age range of 18 to 2 8 y took part in mineral balance studies. The balance periods ranged from 5 to 12 d. In a given experiment, the diet of each subject contained the same quantity of food, although this varied between experiments, and was supplied during the balance period without consideration of body weight. In the data of all the studies (n=109), the balances of Ca and Mg did not correlate positively with Na intake. However, when the data of the highest Na study were excluded, the balances of Ca and Mg correlated positively with Na Intakes The mean value for the regression equation between Na intake and Ca and Mg balances when the respective balance was equal to zero were, 63.308 mg Na/kg BW/d (Ca: n=96, r²=0.134) and 60.977 mg Nalkg BW/d (Mg: n=96, r²=0.268), respectively, These values are considerably higher than Na requirements esti mated by inevitable Na loss. Low dietary Na may therefore be a risk factor for maintaining positive balances of Ca and Mg.

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The regulatory mechanisms of riboflavin biosynthesis in the resting cells of a riboflavin-adenine-deficient mutant of Bacillus subtilis were examined. The growth and pH of the medium remained unchanged in spite of the administration of 0-200μg/mL riboflavin to the medium during incubation of the resting cells for 17 h. However, the formation of 6, 7-dimethyl-8-ribityllumazine (DMRL) and flavin adenine dinucleotide (FAD) was restricted and augmented and then reached its plateau, showing an inverse relation in the addition of riboflavin up to 50μg/mL to the medium and a parallel relation in the supplementation of riboflavin up to 200μg/mL to the medium. In the experiments, the amount of flavin mononucleotide (FMN) was negligible and riboflavin was not detected in the resting cells. The results indicated that not the repression of related enzymes but negative feedback inhibition by FAD, but not that by riboflavin or FINN, is operative in the biosynthetic pathway of riboflavin in the riboflavin adenine double-less mutant of Bacillus subtilis.

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We cloned and analyzed the 5'-flanking region of the human thiamin pyrophosphokinase gene (hTPK1). Truncation analysis using transiently transfected HepG2 cells revealed the minimal region required for basal activity of the hTPK1 promoter, which was encoded in a sequence between -105 and +441 relative to the transcription start site. In an electrophoretic mobility shift assay using the nuclear extracts from HepG2 cells and the synthetic oligonucleotide containing the Sp 1 site, specific DNA-protein complexes were identified. These findings indicate the importance of the Spl cis-element in regulating the hTPK1 gene expression.

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The effects of y-aminobutyric acid (GABA) in rats with experimental diabetes mellitus were examined, Diabetes mellitus was induced in adult male Wistar rats by streptozotocin (STZ) injection. Oral administration of GABA (100 or 200mg/kg body weight/d) for 10 d to the diabetic rats resulted in a significant decrease in their serum glucose level. GABA also reduced the level of glycosylated protein in serum, indicating an improvement of hyperglycemic conditions, Rats With STZ-induced diabetes showed arrested body weight gain and an increase in both liver and kidney weight, whereas oral administration of GABA attenuated the organ hypertrophy induced by hyperglycemia. In addition, the degree of serum thiobarbituric acid (TBA)-reactive substance level was significantly lower in the rats treated with 100mg GABA, and the degree of TBA-reactive substance in the liver and kidney was reduced by GABA in a dose-dependent manner. These results suggest that GABA treatment protects against the development of diabetic complications resulting from impaired glucose metabolism and enhanced oxidative stress.

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The effects of proanthocyanidin-rich extract in rats subjected to renal Ischemia-reperfusion were examined. Proanthocyanidin-rich extract, which is prepared from grape seeds (Vitis vinifera L.), was given orally at doses of 5 and 10mg/kg body weight/ d for 20 consecutive days prior to Ischemia-reperfusion. Administration of proanthocyanU din-rich extract attenuated renal dysfunction, as indicated by serum urea nitrogen and creatinine levels. Additionally, in the ischemic-reperfused kidneys, increased levels of thiobarbituric acid (TBA)-reactive substance and alterations of antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase (GSH-Px) were observed. Proanthocyanidin-rich extract-treated groups showed significantly reduced renal TBA-reactive substance levels and enhanced catalase and GSH-Px activities, These results suggest that proanthocyanidin-rich extract has protective effects against Ischemia reperfusion-induced renal damage associated with oxidative stress.

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The aim of this study was to investigate whether a mucus layer covers the surface of various animal feces and, if so, to show the structure and mucin composition of this layer. The freshly excreted feces of mice, rats, guinea pigs, rabbits and humans were fixed with Carnoy solution, Cross-sections approximately 5μm thick were stained with alcian blue (AB) or the periodic acid Schiff (PAS) reaction, We measured the thickness of the mucus layer on the fecal surface of these sections. The fecal surface was covered with a continuous mucus layer in all specimens. The mucus layers of mice, rats and humans consisted of the alternate stratification of AB-positive and PAS-positive mucin layers. In contrast, the mucus layer consisted of an inner PAS-positive neutral mucin layer and an outer AB-positive acidic mucin layer in guinea pigs and rabbits. The average thicknesses of the mucus layers upon the fecal surfaces for mice, rats, guinea pigs, rabbits and humans were 19±12, 22±14, 15±4.6, 19±14 and 17±11μcm, respectively. These results demonstrated that the fecal surfaces are covered with continuous mucus layers in rodents, rabbits and humans, with substructures varying among species.

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We systematically reviewed cohort studies on the effect of nutrient and food intake (except for alcohol) on the incidence of type 2 diabetes, which had been published in English as of lay 2004. Using the MEDLINE (PubMed) database as well as reference lists of searched papers, 15 individual cohort studies (a total of 31 papers) were identified. The number of subjects (n=895-85, 060), follow-up length (5.9-23 y), the number of diabetes cases (n=74-4, 085), dietary assessment method used (simple food questionnaire, food frequency questionnaire, food frequency interview, diet history interview, and 24-h recall), and method of case ascertainment (questionnaire, oral glucose tolerance test, fasting glucose level, death certificate, and nationwide registry) varied among studies. For nutrients, intakes of vegetable fat, polyunsaturated fatty acid, dietary fiber (particularly cereal fiber), magnesium, and caffeine were significantly inversely correlated and intakes of traps fatty acid and heme-iron, glycemic index, and glycemic load were significantly positively correlated with the incidence of type 2 diabetes in several papers. For foods and food groups, several papers showed significantly decreased risk for type 2 diabetes with the higher consumption of grain (particularly whole grain) and coffee, and significantly increased risk with processed meat consumption. Because all the studies were carried out in western countries, however, research in non-western countries including Japan is needed.

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