Biofactors - Volume 12, issue 1-4

Authors: Hajime Ohigashi, | Toshihiko Osawa, | Junji Terao, | Shaw Watanabe, | Toshikazu Yoshikawa,

Article Type: Other

Citation: BioFactors, vol. 12, no. 1-4, pp. 1-1, 2000

Authors: Paul Talalay,

Article Type: Research Article

Abstract: Induction of Phase 2 enzymes is an effective and sufficient strategy for achieving protection against the toxic and neoplastic effects of many carcinogens. It is proposed that the concept of Phase 2 enzymes as being responsible only for the conjugation of functionalized xenobiotics with endogenous cellular ligands such as glutathione (glutathione S-transferases) and glucuronic acid (UDP-glucuronosyltransferases) be expanded to include proteins with the following common characteristics: (a) coordinate induction by a broad …range of chemical agents that all have the capacity to react with sulfhydryl groups; (b) possible regulation by common promoter elements; and (c) catalysis of reactions that lead to comprehensive protection against electrophile and reactive oxygen toxicities, by a wide variety of mechanisms. These mechanisms include: conjugation with endogenous ligands, chemical modification of reactive features of molecules that can damage DNA and other macromolecules, and generation or augementation of cellular antioxidants. In addition to the above conjugating enzymes, a provisional and partial list of Phase 2 proteins might include: NAD(P)H:quinone reductase, epoxide hydrolase, dihydrodiol dehydrogenase, \gamma -glutamylcysteine synthetase, heme oxygenase-1, leukotriene B_4 dehydrogenase, aflatoxin B_1 dehydrogenase, and ferritin. Show more

Keywords: glutathione transferase, glutathione, NAD(P)H:quinone reductase, heme oxygenase, \gamma-glutamylcysteine synthetase, epoxide hydrolase, ferritin, electrophile toxicity, redox cycling, antioxidants, reactive oxygen species

Citation: BioFactors, vol. 12, no. 1-4, pp. 5-11, 2000

Authors: Soichi Arai,

Article Type: Research Article

Abstract: In 1984, a new science related to functional food was initiated by a National Project team under the auspices of the Japan Ministry of Education and Science. It was followed by a great many academic and industrial studies to occupy a central position in the field of food and nutritional sciences. In 1993, the Ministry of Health and Welfare established a policy of ``Foods for Specified Health Uses'' (FOSHU) by which health claims of some selected …functional foods are legally permitted. Up to now (November 22, 1999), 167 FOSHU products have been born. Since the time (1984) when the concept of ``functional food'' was proposed, it seems that the science in Japan has been progressing along, among others, a unique path of development. The uniqueness is seen in the development of functional foods by minimizing undesirable as well as maximizing desirable food factors. Hypoallergenic foods, developed from their materials by removing allergens, offer a good example. Another characteristic may be found in the field of sensory science which aims at elucidating a molecular logic of the senses of taste and smell in reference to their effects on physiological systems in the body. The paper discusses some characteristics of functional food science in Japan, with special emphasis on these topics. Show more

Citation: BioFactors, vol. 12, no. 1-4, pp. 13-16, 2000

Authors: Zigang Dong,

Article Type: Research Article

Abstract: Consumption of plant-derived foods, especially fruits and vegetables, has been linked to decreased risk of cancer. Laboratory studies with animals and cells in culture have shown cancer preventive activity of chemicals isolated from soy, tea, rice and many green, yellow and orange fruits and vegetables. Using cell culture, transgenic mice and knockout mice models to examine the anti-cancer effects of these dietary factors at the molecular level, we found that (1) (- )-epigallocatechin gallate …(EGCG), the major active polyphenol in green tea, and theaflavins, the major active components in black tea, inhibit epidermal growth factor (EGF)- or 12-O -tetradecanoylphorbol-13-acetate (TPA)-induced JB6 cell transformation. At the same dose range that inhibited cell transformation, EGCG and theaflavins inhibited activator protein-1 (AP-1) activation. These compounds also inhibited ultraviolet B (UVB)-induced AP-1 and nuclear factor kappa B (NF\kappa B)-dependent transcriptional activation; (2) resveratrol, found at high levels in grapes, inhibited cell transformation through the induction of apoptosis, mediated through JNK and p53-dependent pathways; (3) inositol hexaphosphate (InsP6), an active compound from rice and other grains, inhibited TPA- or EGF-induced transformation and signal transduction through its effects on phosphatidylinositol-3 kinase (PI-3) kinase; (4) phenethyl isothiocyanate (PEITC), which occurs as a conjugate in certain cruciferous vegetables, inhibited cell transformation corresponding with the induction of apoptosis. An elevation of p53 is required for PEITC-induced apoptosis. Our studies indicated that the chemopreventive effect of these food factors may be mediated by their effects on different signal transduction pathways; (5) retinoids (vitamin A and its metabolites) inhibited tumor promoter-induced cell transformation and tumor promotion in transgenic mice through the inhibition of AP-1 action but not through the activation of retinoic acid response element (RARE). Show more

Citation: BioFactors, vol. 12, no. 1-4, pp. 17-28, 2000

Authors: Shuichi Kaminogawa,

Article Type: Research Article

Citation: BioFactors, vol. 12, no. 1-4, pp. 29-32, 2000

Authors: Mamoru Nishimuta,

Article Type: Research Article

Abstract: A new concept of grouping of minerals, which will be helpful for understanding the actual status of human health, on the basic of elementological biology.

Keywords: intracellular minerals, extracellular minerals, bone minerals

Citation: BioFactors, vol. 12, no. 1-4, pp. 35-38, 2000

Authors: Gerald F. Combs, Jr.,

Article Type: Research Article

Abstract: Micronutrient deficiencies affect nearly half the world's population, impairing child development, reducing work productivity, and increasing mortality and morbidity rates by affecting both infectious and chronic diseases. To feed a growing world, it will be necessary to consider agriculture in the broad context of a food system as an instrument of public health and, thus, to address nutrient balance while also seeking sustainability. Such efforts would include increasing cropping system diversity, enhancing …micronutrient outputs and promoting environmental sustainability. Example of this approach are presented for the essential trace element selenium (Se), which at high intakes can reduce cancer risks but is deficient in many parts of the world. Food systems-based approaches are discussed for preventing Se deficiency by enhancing intakes of any of several biologically available forms of Se, and for reducing cancer risk by enhancing intakes of forms of the element that support anti-tumorigenic Se-metabolites. Show more

Keywords: food system, micronutrient, selenium, cancer, carcinogenesis, chemoprevention

Citation: BioFactors, vol. 12, no. 1-4, pp. 39-43, 2000

Authors: Mohamed Abdulla, | Per Gruber,

Article Type: Research Article

Abstract: Carcinogenesis encompasses a prolonged accumulation of injuries at several different biological levels and include both genetic and biochemical changes in the cells. At each of these levels, there are several possibilities of intervention in order to prevent, slow down or even halt the gradual march of healthy cells towards malignancy. Diet modification is one such possibility. A number of natural foodstuffs, especially fruits and vegetables contain substantial quantities of molecules that have chemopreventive potential against …cancer development. Such compounds include vitamins, trace elements and a variety of other molecules with antioxidant properties. Carotenoids, flavanoid polyphenols, isoflavones, catechins, and several other components that found in cruciferous vegetables are molecules that are known to protect against the deleterious effect of reactive oxygen species. A number of epidemiological and experimental studies have shown that vitamin C and E, Beta-carotene and the essential trace element selenium can reduce the risk of cancer. Consistent observations during the last few decades that cancer risk is reduced by a diet rich in vegetables, fruits, legumes, grains and green tea have encouraged research to identify several plant components especially phytochemicals that protect against DNA damage. Many of these substances block specific carcinogen pathways. Dietary supplements are part of an overall health program, along with a high intake of fruits and vegetables that help to combat damage to cells, which in turn may initiate cancer development. This paper will review current knowledge concerning diet modification and cancer prevention with special reference to minerals and trace elements. Show more

Keywords: cancer prevention, reactive oxygen species, fruits and vegetables, antioxidants, trace elements

Citation: BioFactors, vol. 12, no. 1-4, pp. 45-51, 2000

Authors: Ritsuko Masuyama and Kazuharu Suzuki,

Article Type: Research Article

Abstract: Dietary intake of high phosphorus (P) is well-described to increase serum levels of PTH, however, how this increased serum PTH affects the PTH actions in major target tissues, particularly in kidney, remains uncovered. We therefore undertook to clarify this point in intact animals fed the high-P diet by examining various parameters of the PTH actions. Twelve weanling Wistar male rats were assigned randomly into the groups; a control group Ca:P=1:1 and a high-P group (Ca:P=1:3) fed …the standard AIN 76 diet supplemented with P (0.5 and 1.5 g/100 g diet). After 3 week feeding, in the high-P diet group, we observed that serum Ca is lowered without difference in serum P when compared to those in the control group. Excretion of urine cAMP, an index of the renal PTH action, was also decreased with higher excretion of urine P by feeding the high P diet. In agreement with the decreased cAMP excretion, a clear reduction in the PTH/PTHrP receptor gene expression estimated by Northern blotting was observed in the kidney irrespective of increased levels of serum PTH. Thus, the present study indicated that high P dietary intake rather reduces the PTH actions in kidney though the serum PTH is increased. Show more

Citation: BioFactors, vol. 12, no. 1-4, pp. 53-58, 2000

Authors: Hiroshi Tsuchita, | Noboru Manabe, | Shinichi Saito,

Article Type: Research Article

Citation: BioFactors, vol. 12, no. 1-4, pp. 59-64, 2000