著者

Katsumi SHIBATA

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.61, no.Supplement, pp.S145-S147, 2015 (Released:2015-11-24)

参考文献数

8

被引用文献数

3 7

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Pyridine nucleotide coenzymes (PNCs) are involved in over 500 enzyme reactions. PNCs are biosynthesized from the amino acid L-tryptophan (L-Trp), as well as the vitamin niacin. Hence, “true” niacin-deficient animals cannot be “created” using nutritional techniques. We wanted to establish a truly niacin-deficient model animal using a protocol that did not involve manipulating dietary L-Trp. We generated mice that are missing the quinolinic acid phosphoribosyltransferase (QPRT) gene. QPRT activity was not detected in qprt−/−mice. The qprt+/+, qprt+/− or qprt−/− mice (8 wk old) were fed a complete diet containing 30 mg nicotinic acid (NiA) and 2.3 g L-Trp/kg diet or an NiA-free diet containing 2.3 g L-Trp/kg diet for 23 d. When qprt−/−mice were fed a complete diet, food intake and body weight gain did not differ from those of the qprt+/+ and the qprt+/− mice. On the other hand, in the qprt−/− mice fed the NiA-free diet, food intake and body weight were reduced to 60% (p<0.01) and 70% (p<0.05) of the corresponding values for the qprt−/− mice fed the complete diet at day 23, respectively. The nutritional levels of niacin such as blood and liver NAD concentrations were also lower in the qprt−/− mice than in the qprt+/+ and the qprt+/− mice. Urinary excretion of quinolinic acid was greater in the qprt−/− mice than in the qprt+/+ and the qprt+/− mice (p<0.01). These data suggest that we generated truly niacin-deficient mice.

著者

Katsumi SHIBATA Tsutomu FUKUWATARI Satoshi SASAKI Mitsue SANO Kahoru SUZUKI Chiaki HIRATSUKA Asami AOKI Chiharu NAGAI

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.59, no.3, pp.178-186, 2013 (Released:2013-07-25)

参考文献数

69

被引用文献数

11 15

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Recent studies have shown that the urinary excretion levels of water-soluble vitamins can be used as biomarkers for the nutritional status of these vitamins. To determine changes in the urinary excretion levels of water-soluble vitamins during pregnant and lactating stages, we surveyed and compared levels of nine water-soluble vitamins in control (non-pregnant and non-lactating women), pregnant and lactating women. Control women (n=37), women in the 2nd (16-27 wk, n=24) and 3rd trimester of pregnancy (over 28 wk, n=32), and early- (0-5 mo, n=54) and late-stage lactating (6-11 mo, n=49) women took part in the survey. The mean age of subjects was ~30 y, and mean height was ~160 cm. A single 24-h urine sample was collected 1 d after the completion of a validated, self-administered comprehensive diet history questionnaire to measure water-soluble vitamins or metabolites. The average intake of each water-soluble vitamin was ≈ the estimated average requirement value and adequate intake for the Japanese Dietary Reference Intakes in all life stages, except for vitamin B6 and folate intakes during pregnancy. No change was observed in the urinary excretion levels of vitamin B2, vitamin B6, vitamin B12, biotin or vitamin C among stages. Urine nicotinamide and folate levels were higher in pregnant women than in control women. Urine excretion level of vitamin B1 decreased during lactation and that of pantothenic acid decreased during pregnancy and lactation. These results provide valuable information for setting the Dietary Reference Intakes of water-soluble vitamins for pregnant and lactating women.

著者

Katsumi SHIBATA Akiko TACHIKI Kana MUKAEDA Tsutomu FUKUWATARI Satoshi SASAKI Yoshiki JINNO

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.59, no.4, pp.343-346, 2013 (Released:2013-09-24)

参考文献数

25

被引用文献数

3 6

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Most Japanese women do not consume the estimated average requirement of vitamin B6 (1.7 mg/d) during pregnancy. Nevertheless, these deficiencies are not reported. We investigated a nutritional biomarker of vitamin B6 in pregnant Japanese women as well as their vitamin B6 intakes. Vitamin B6 intakes in the first, second, and third trimesters of pregnancy, and 1 mo after delivery were 0.79±0.61 (n=56), 0.81±0.29 (n=71), 0.90±0.35 (n=92), and 1.00±0.31 (n=44) mg/d, respectively. Plasma pyridoxal 5'-phosphate (PLP) concentrations in the first, second, and third trimesters of pregnancy, and 1 mo after delivery were 57.1±27.6 (n=56), 23.3±16.7 (n=71), 18.3±12.5 (n=92), and 43.9±33.4 (n=44) nmol/L, respectively. The plasma concentrations significantly decreased in the second and third trimesters of pregnancy compared to values from the first trimester (p<0.05), and these concentrations returned to the values of the first trimester of pregnancy 1 mo after birth.

著者

Katsumi SHIBATA Tsutomu FUKUWATARI

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.60, no.5, pp.334-339, 2014 (Released:2015-01-16)

参考文献数

28

被引用文献数

3 9

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Picolinic acid (PiA) is an endogenous metabolite of tryptophan that has been reported to possess a wide range of physiological actions. We investigated the effects of dietary PiA on the metabolism of tryptophan to nicotinamide in growing rats. Feeding an ordinary diet containing 1% PiA to growing rats (6 wk) caused death within a few days. Toxicity of PiA was higher than that of analogs such as nicotinic acid and quinolinic acid. Feeding an ordinary diet containing 0.05% and 0.1% PiA did not elicit decreased intake of food or loss in body weight. PiA did not affect the in vitro liver activities of quinolinic acid phosphoribosyltransferase or α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSDase, a Zn-dependent enzyme). Concentrations of NAD and NADP in the liver and blood were not affected by PiA. PiA administration did not affect tryptophan metabolites such as anthranilic acid, kynurenic acid, and xanthurenic acid. However, quinolinic acid and subsequent metabolites such as nicotinamide and its catabolites were increased by administration of a diet containing 0.05% PiA but not by a 0.1% PiA diet. These results suggest that the in vivo activity of ACMSDase is controlled by the Zn level. Therefore, a small amount of PiA has a beneficial effect for conversion of tryptophan to nicotinamide, but an excessive amount of PiA can be very toxic.

著者

Tsutomu FUKUWATARI Erina YOSHIDA Kei TAKAHASHI Katsumi SHIBATA

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.56, no.1, pp.19-26, 2010 (Released:2010-03-31)

参考文献数

32

被引用文献数

9 14

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Recent studies showed that the urinary excretion of the water-soluble vitamins can be useful as a nutritional index. To determine how fasting affects urinary excretion of water-soluble vitamins, a human study and an animal experiment were conducted. In the human study, the 24-h urinary excretion of water-soluble vitamins in 12 healthy Japanese adults fasting for a day was measured. One-day fasting drastically decreased urinary thiamin content to 30%, and increased urinary riboflavin content by 3-fold. Other water-soluble vitamin contents did not show significant change by fasting. To further investigate the alterations of water-soluble vitamin status by starvation, rats were starved for 3 d, and water-soluble vitamin contents in the liver, blood and urine were measured during starvation. Urinary excretion of thiamin, riboflavin, vitamin B6 metabolite 4-pyridoxic acid, nicotinamide metabolites and folate decreased during starvation, but that of vitamin B12, pantothenic acid and biotin did not. As for blood vitamin levels, only blood vitamin B1, plasma PLP and plasma folate levels decreased with starvation. All water-soluble vitamin contents in the liver decreased during starvation, whereas vitamin concentrations in the liver did not decrease. Starvation decreased only concentrations of vitamin B12 and folate in the skeletal muscle. These results suggest that water-soluble vitamins were released from the liver, and supplied to the peripheral tissues to maintain vitamin nutrition. Our human study also suggested that the effect of fasting should be taken into consideration for subjects showing low urinary thiamin and high urinary riboflavin.

著者

Shigeo Aibara Katsumi Shibata Yuhei Morita

出版者

日本宇宙生物科学会

雑誌

Biological Sciences in Space (ISSN:09149201)

巻号頁・発行日

vol.11, no.4, pp.339-345, 1997 (Released:2006-02-01)

参考文献数

17

被引用文献数

1 1

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A space experiment involving protein crystallization was conducted in a microgravity environment using the space shuttle “Endeavour”of STS-47, on a 9-day mission from September 12th to 20th in 1992. The crystallization was carried out according to a batch method, and 5 proteins were selected as flight samples for crystallization. Two of these proteins : hen egg-white lysozyme and co-amino acid: pyruvate aminotransferase from Pseudomonas sp. F-126, were obtained as single crystals of good diffraction quality. Since 1992 we have carried out several space experiments for protein crystallization aboard space shuttles and the space station MIR. Our experimental results obtained mainly from hen egg-white lysozyme are described below, focusing on the effects of microgravity on protein crystal growth.

著者

Katsumi SHIBATA Tsutomu FUKUWATARI

出版者

Center for Academic Publications Japan

雑誌

Journal of Nutritional Science and Vitaminology (ISSN:03014800)

巻号頁・発行日

vol.59, no.2, pp.87-92, 2013 (Released:2013-05-31)

参考文献数

18

被引用文献数

2 5

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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.