著者
天野 晶子 石神 昭人
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.83, no.1, pp.24-26, 2009-01-25 (Released:2017-10-10)
参考文献数
21
被引用文献数
1
著者
平岡 真実 香川 靖雄
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.89, no.2, pp.59-64, 2015-02-25 (Released:2017-08-10)

It is known that individuals respond differently to the same dietary intake differently. Nutrigenetics is an essential discipline to study gene-based differences in response to dietary components for nutrition and dietetics practice. One of the best-known examples for nutrigenetics is the polymorphism of methylenetetrahydrofolate reductase (MTHFR) C677T. The presence of the C677T mutation in MTHFR gene is associated with a reduction of MTHFR enzyme activity. This reduction of MTHFR enzyme activity may cause an increase in plasma homocysteine level which becomes risk factors for cardiovascular disease, cognitive impairment and neural tube defects. Plasma homocysteine level is responsive to intervention with folic acid and related vitamin B group. "Sakado Folate Projects" is a health promotion with personalized nutrition intervention based on MTHFR C677T polymorphisms for prevention of these diseases associated with hyperhomocysteinemia. An increase in serum folate level and a decrease in serum homocysteine level were observed at 4 months after the onset of this intervention and these changes were particularly marked in individuals with TT genotype. This finding suggests that personalized nutrition intervention based on genetic information is effective in motivating individuals to change their lifestyle habit.
著者
宮内 正厚 中島 英彰 平井 千津子
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.88, no.7, pp.349-357, 2014-07-25 (Released:2017-08-10)
被引用文献数
1

In recent years, the importance of solar exposure for vitamin D synthesis in the human body has been pointed out. The solar exposure time necessary for the synthesis of vitamin D depends largely on geographical location, season, time of day, weather, exposed skin area, etc. Using numerical simulations we estimated that if 10 μg vitamin D were to be synthesized entirely by solar exposure to skin type III (SPT), which is considered to be the most typical skin type for Japanese people, it would necessitate 6.4 min horizontal exposure of a 600 cm^2 skin area, corresponding to the face and the back of both hands, under cloudless sky at 12:00 o'clock in July in Tsukuba. Under the same conditions, it would take 20.8 min to reach 1 MED (Minimum Erythemal Dose) which is thought to be the harmful UV exposure level for human skin. In other words, approximately 31% of the time before the skin gets red is enough for the synthesis of 10 μg vitamin D a day. On the other hand, in Sapporo which is located in the northern part of the Japanese Archipelago, the corresponding durations are 8.4 min and 27.0 min, respectively under the same conditions as in Tsukuba, whereas the necessary time in December would be 139 min and 296 min, respectively. Although the sufficient amount of vitamin D cannot be obtained by short-time exposure to solar radiation, it is thought that long-time exposure might not damage the skin. It can be concluded that for a skin area of 600 cm^2 in horizontal position, exposure time until damage would occur is generally 3 times larger than what is necessary for the synthesis of 10 μg vitamin D under strong UV radiation. It should be noted that generally, with a larger exposed skin area the solar exposure time for vitamin D synthesis could be considerably shortened.
著者
天野 晶子 石神 昭人
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.87, no.9, pp.492-496, 2013-09-25 (Released:2017-08-10)

Vitamin C (VC, L-ascorbic acid) transport is mediated by specific transporters, such as sodium-dependent vitamin C transporter (SVCT) 1 and 2. SVCT1 and 2 have a functional role in secondary active transport of VC from the outside to the inside of cells at the expense of sodium electrochemical gradient across the cell membrane. Recent studies revealed that the effect of SVCTs gene polymorphisms on risk of preterm birth and any diseases. Moreover, some paper reported that the effect of SVCTs gene polymorphisms on VC concentration in human blood and interactions with other antioxidant related genes. In this paper, we review recent insights into the relationships between SVCTs gene polymorphisms and health and disease risk.
著者
槇島 誠
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.85, no.2, pp.47-56, 2011-02-25 (Released:2017-10-10)
参考文献数
51

Nuclear receptors belonging to the NR1H and NR1I subfamilies, including vitamin D receptor (VDR, NR1I1), control cholesterol and bile acid metabolism. Bile acids are detergents essential for the digestion and intestinal absorption of hydrophobic nutrients, such as triacylglycerol, cholesterol and lipid-soluble vitamins, including vitamin D.Primary bile acids are generated from cholesterol and are secreted in bile as glycine and taurine conjugates. The intestinal microflora convert the primary bile acids to the secondary bile acids, including lithocholic acid (LCA). VDR, a receptor for 1,25-dihydroxyvitamin D_3(1,25(OH)_2D_3), acts as a bile acid receptor with specificity for the secondary bile acid LCA and its derivatives. VDR activation by 1,25(OH)_2D_3 or LCA induces the xenobiotic metabolism of bile acids. Synthetic LCA derivatives induce tissue VDR activation without inducing hypercalcemia in mice. VDR acts as a bile acid sensor as well as an endocrine receptor for vitamin D signaling.
著者
近藤 厚生 岡井 いくよ 早川 ちさ 下須賀 洋一
出版者
公益社団法人 日本ビタミン学会
雑誌
ビタミン (ISSN:0006386X)
巻号頁・発行日
vol.83, no.5-6, pp.250-255, 2009-06-25 (Released:2017-10-10)
参考文献数
16

We have been assessing awareness of a role of folic acid, intake of folate supplements and dietary folate consumption among pregnant women during the past 6 years. A total of 6902 pregnant women responded to our questionnaires distributed from 2002 to 2007. Dietary folate was measured by analyzing food records completed by 441 pregnant women from 2003 to 2007. Rates of awareness and rates of folate supplementation were considerably low, 15% and 9%, respectively, in 2002, but increased year after year to 39% and 43%, respectively, in 2007. Of the 441 pregnant women who reported their food records 150 (34%) simultaneously took folate supplements. Although the amount of dietary folate consumed averaged 336μg/day in all the women, 126 women in the 1^<st> trimester consumed only 283μg/day, 120μg less than what was recommended by the Government. It was further observed that 61% of the women in the 1^<st> trimester neither consumed 400μg of dietary folate nor took folate supplements suggesting that the majority of the women were facing a real risk of conceiving fetuses afflicted with neural tube defects. Following strategies seem necessary to suppress incidence of neural tube defects in Japan: First, importance of folate supplementation should be stressed in a booklet for pregnant women. Second, the Government should repeatedly send folate information in relation to developing fetuses to the general public. Third, folate information should be given to young girls at curriculums of the junior and senior high school. Fourth, folate supplements should be given free for those women who wish to conceive. Finally, implementation of food fortification with folic acid should be seriously considered by the Government.