著者
井上 裕康
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.78, no.12, pp.621-623, 2004-12-25 (Released:2017-10-10)
参考文献数
13

レスベラトロールは赤ワインに含まれる抗酸化作用を持つフィトアレキシン(抗菌性物質)である. レスベラトロールは中等度のワイン消費が心血管病, 脳卒中, 痴呆の危険度と負の相関を示す, いわゆる「フレンチパラドックス」に関与する物質と考えられてきた. 我々は最近, レスベラトロールが核内受容体PPAR(peroxisome proliferators activated receptor)αとPPARγを選択的に活性化すること, さらにPPARα活性化が脳保護効果をもたらすことを見いだした. これらの知見は「フレンチパラドックス」を説明する新しい作用機構を提供すると考えている. 一方で, レスベラトロールは寿命延長効果を持つカロリー制限模倣物質であること, オレイルエタノールアミドがPPARαの新しい内因性リガンドであり, その活性化によって食欲をコントロールすることが報告されている. そこでこれらの知見を含めて, 今後の展望とともに紹介したい.
著者
妹尾 春樹 畑 隆一郎
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.68, no.9, pp.501-513, 1994-09-25 (Released:2018-03-30)

Stellate cells (vitamin A-storing cells, lipocytes, fat-storing cells, Ito cells) exist in the perisinusoidal space of the hepatic lobule, and store 80% of retinoids in the whole body as retinyl palmitate in lipid droplets in the cytoplasm. Under physiological conditions, these cells play key roles in the control of retinoid homeostasis ; they express specific receptors for retinol-binding protein (RBP), a binding protein specific for retinol, on their cell surface, and take up the complex of retinol and RBP by receptor-mediated endocytosis. Whereas, under pathological conditions such as liver cirrhosis, these cells lose retinoids, and synthesize a large amount of extracellular matrix (ECM) components including collagen, proteoglycan and adhesive glycoproteins. Morphology of these cells also changes from the star-shaped stellate cells to that of fibroblasts or myofibroblasts. ECM components regulate the morphology, proliferation, and functions of the stellate cells. L-ascorbic acid 2-phosphate, a long-acting vitamin C derivative, further modulates this cellular regulation by ECM components.
著者
小熊 敦之 芦沢 萌恵 江草(雜賀) 愛 片山 努 古屋 元宏 赤尾 友雪 西村 敏英
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.10, pp.543-548, 2013-10-25 (Released:2017-08-10)

We examined the effects of vitamin B_1 (B_1) and fat added to a feed on their accumulation and glucose- and lipid-metabolism in the porcine liver. B_1 content in the livers of pigs fed a feed supplemented with 15 ppm B_1-supplemented feed (B+ group) was significantly higher than that in the livers of pigs fed the usual dosage of 1.5 ppm B_1 (Control group). B_1 content in the livers of pigs given a feed with 1.5 ppm B_1 plus 3% fat (F+ group) or a feed with 15 ppm B_1 plus 3% fat (B+F+ group) was significantly higher than that in pigs given a feed with 15 ppm B_1 (B+ group) or controls. The liver fat content in the B+F+ group was lower than that in the B+ group. Analysis of liver mRNA levels showed that gene expression of β-oxidation-related proteins increased in B_1-supplemented groups. Glycolytic pathway- and TCA cycle-related gene expression levels were also increased with fat supplementation. These results indicated that, in pigs with co-supplementation of high dose of B_1 and fat, glucose and lipid metabolism was enhanced in the liver.
著者
錦見 盛光
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.81, no.1, pp.1-8, 2007-01-25 (Released:2017-10-10)
参考文献数
35

L-Ascorbic acid is synthesized by animals and plants, and its analogues in fungi. Studies in the 1950s showed that scurvy-prone species, such as humans, other primates, and guinea pigs, do not possess L-gulono-γ-lactone oxidase, the terminal enzyme of the L-ascorbic acid biosynthetic pathway in animals. We first cloned a cDNA for this enzyme of rat, with which the isofunctinal enzymes of plants and fungi were later shown to be homologous at the gene level. Using the cDNA as a probe, its related DNA sequences of human and guinea pig were cloned and their gene structures were disclosed. Of note is the tremendous deterioration of the genes such as deletion of exons and nucleotide(s), nonconformity to the GT/AG rule at the intronexon junction, and occurrence of stop codons as well as a large number of substations at the amino acid level. In contrast, the genetic abnormality of osteogenic disorder Shionogi (ODS) rat was found to be due to a single missense mutation in the L-gulono-γ-lactone oxidase gene. Recent our study revealed that the knockout mouse deficient for senescence marker protein-30 was subject to scurvy when fed a vitamin C deficient diet. As a matter of fact, this protein was proven to be the gluconolactonase that catalyzes the penultimate step of the L-ascorbic acid biosynthetic pathway.
著者
鈴木 洋一 坂本 修 真下 陽一 羽田 明
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.86, no.9, pp.499-507, 2012-09-25 (Released:2017-10-10)
参考文献数
31

Biotin is a water-soluble vitamin and a cofactor of several types of carboxylases. Insufficient intake of biotin and a congenital deficiency of enzymes requiring biotin as a cofactor in cells cause clinical symptoms called multiple carboxylase deficiency (MCD). In recent years, several reports have shown that infants with food allergy and/or atopic eczema have developed MCD after being fed with peptide formulas. Peptide formulas available in Japan contain very little biotin because biotin has not been permitted to be added to regular foods as an additive. This, however, may lead to nutritional biotin deficiency in some infants fed with such a peptide milk. We investigated the incidence of nutritional biotin deficiency and congenital enzyme deficiency in Japan. We sent a questionnaire to 921 hospitals with a pediatric department to cover all areas of Japan. The response rate was 64%. The rate of hospitals that use peptide milk in the therapy of allergic diseases was 49%. The estimated incidence of biotin deficiency was at least 70 cases in the last 10 years. Since the first diagnosis of holocarboxylase synthetase deficiency (HCSD) in 1982, HCSD and biotinidase deficiency have been confirmed in 28 and 2 cases, respectively. These data suggest that the incidence of congenital enzyme deficiency is about 1 case per year. Supplementation of biotin is highly recommended when infants are fed with peptide milk in Japan.
著者
矢野 友啓
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.12, pp.561-572, 2015-12-25 (Released:2017-08-10)

It is well known that vitamin E acts as a useful preventive agent against several types of cancers and stroke. However, there are conflicting results on a role of vitamin E in the prevention of these diseases. In order to clarify the conflicting results, meta-analysis of current results obtained from randomized controlled trials (RCTs) was conducted. Meta-analysis of 7 RCTs on cancer identified showed no significant difference on the effect of vitamin E supplementation on incidence and mortality in cancers tested. However, there was heterogeneity in the meta-analysis of prostate cancer incidence, indicating the possibility that vitamin E supplementation has a suppressive effect against the cancer in some cases. With respect to incidence and mortality in stroke, meta-analysis of 6 RCTs identified was conducted, and vitamin E supplementation significantly reduced the incidence of ischemic stroke, but not hemorrhagic stroke. Thus, it is suggested that vitamin E supplementation has a preventive effect on ischemic stroke.
著者
久保寺 登
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.2, pp.95-103, 2013-02-25 (Released:2017-08-10)
参考文献数
35

In vitamin D research, there are three milestones from the perspective of pharmaceutical studies. The first represents the early stage of vitamin D research and involves the discovery of vitamin D and its physiological significance as an anti-rickets factor. The second is the elucidation of the vitamin D activation pathway in the body and the discovery of the biologically active metabolites of vitamin D. The clinical application of active vitamin D or its prodrug was also attempted to make up for the deficiency caused by poor vitamin D activation. The third is characterized by the discovery of the differentiation-inducing properties of active vitamin D. This showed the diversity of the physiological actions of active vitamin D, which initially had been thought only to contribute to bone and calcium metabolism. Because these physiological actions were clinically useful, the third discovery revealed opportunities for the development of drugs appropriate to specific purposes by synthesizing analogs to separate biological effects. Active vitamin D analogs based on the findings during the third milestone are now commercially available and are contributing to current clinical practice. This article discusses the various milestones outlining vitamin D and analogs in terms of clinical applications and pharmaceutical studies.