Polyphenols from food materials were investigated to determine their physiological functions and the mechanisms responsible for them. The results obtained are summarized as follows: (1) Flavanonols present in tea from leaves of Engelhardtia chrysolepis and Ampelopsis grossedentata exhibited activity to prevent liver injury due to oxidative stress. (2) Anthocyanins such as malvin, rubrobrassicin and nasunin showed antioxidative and radical scavenging activities, along with activity to reduce the levels of both serum and liver total cholesterol and increase the level of HDL-cholesterol, suggesting that they are active in improving the levels of lipid. Some antho-cyanins were effective in suppressing oxidative stress caused by radical generation in vivo. Cyanidin glycosides, which are low-molecular-weight anthocyanins, exhibited activity to suppress in vivo oxidation during the progres-sion of diabetes. (3) Among the catechins, (−)-epigallocatechin gallate suppressed in vivo oxidation caused by radical generation in vivo most effectively, followed by (−)-epicatechin gallate, and/or (−)-epigallocatechin. (−)-Epicatechin had no effect. (4) Glycosylation of flavonol at its 3´ and/or 4´ position did not affect its activity to suppress liver injury caused by in vivo oxidation, but glycosylation of flavonol at its 7´ position caused a marked decrease in its suppressive activity on liver injury. (5) Flavones with a sugar moiety at the 7 position showed enhanced protective activity against liver injury when the sugar moiety was malonylated.

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Phosphate is widely distributed in the body and is involved in cell signaling, energy metabolism, nucleic acid synthesis, and the maintenance of acid-base balance by urinary buffering. Homeostasis of inorganic phosphate (Pi) is an essential physiological function as manifested by syndromes that arise from hypo- or hyperphosphatemic states. Pi wasting is linked with rickets and osteomalacia, whereas hyperphosphatemia is associated with an increased risk cardiovascular disease. The maintenance of constant circulating levels of Pi depends on the coordinated activity of three major organs, the intestine the kidney, and the bone. Three types of Na/Pi co-transporters (SLC17, SLC20, SLC34) have been identified in the three major organs. Gene knockout mice have been created for the types I-III of Na/Pi co-transporters. Furthermore, the identification of genetic alterations in Mendelian disorders of hypophosphatemia and hyperphosphatemia has led to the isolation of novel genes (FGF-23/Klotho) and the identification of new roles for existing proteins in the control of Pi metabolism. The discovery of FGF23/klotho has clarified much of our understanding of abnormalities in phosphate and vitamin D metabolism in chronic kidney disease (CKD). Emerging data highlight the potential of FGF23 as a novel diagnostic to identify CKD patients at the highest risk for disease progression, cardiovascular disease, and death, and those who might benefit from early phosphate-related therapies before the onset of overt hyperphosphatemia. This review will summarized recent insights into the roles of Na/Pi-cotransporters in Pi homeostasis and will discuss how these discoveries have uncovered novel aspect of Pi homeostasis.

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The aim of this study was to identify the reinforcement effect of umami seasoning (monosodium glutamate) on preferences for cooked dishes. Twenty women in their twenties and thirty healthy middle-age women participated. From 0%, 0.25%, 0.5% and 1% umami seasoning concentrations, it was chosen 0% and two concentrations of umami seasoning to prepared twenty different dishes. Each dish was prepared without the 0% and the two umami seasoning concentrations. The women were then asked to rate the most palatable dishes according to the concentration of umami seasoning. The middle-aged women showed a significant preference for 7 dishes that were prepared with 0.5% umami seasoning and 1 dish prepared with 0.25%. The palatability did not change in those dishes prepared without umami seasoning (0%). The young women showed similar responses. These results suggest that depending on individual dishes, the palatability may be increased by adding umami seasoning.

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We undertook a population-based study to examine the association between smoking status and nutrient and food group intakes among Japanese adults. A total of 5,350 participants who were at least 40 years of age took part in this study. Nutrient and food group intakes were examined using a validated, brief-type self-administered diet history questionnaire (BDHQ) ; smoking status was self-reported. The associations between nutrient and food group intakes and smoking status were analyzed. Among the men and women, 42.3% and 8.6%, respectively, were current smokers, and in both sexes current smokers were younger than never-smokers. Current smokers had a higher consumption of alcoholic and non-alcoholic beverages than never-smokers, whereas current smokers consumed significantly less antioxidants, dietary fiber, minerals, green-yellow vegetables, and fruit. Ex-smokers, accounting for 42.3% of the men and 5.6% of the women, had a higher intake of alcoholic beverages, but there were no gender differences in the intake of beta-carotene and green-yellow vegetables. Our results confirm that Japanese smokers have unhealthier dietary habits than non-smokers.

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Petit vert is a hybrid of Brussels sprout and kale, and was newly developed in Japan in 1991. The health benefits of Petit vert are attracting much attention because of its high vitamin and mineral contents compared with other vegetables. We examined the anti-obesitic effect of Petit vert on mice fed a high-fat/glucose/cholesterol diet (Western diet; W). The mice were divided into 4 groups: CT (standard diet), PV (standard diet including 5% Petit vert), W and W+5% Petit vert (WPV). Petit vert significantly prevented the increase of body weight and abdominal fat tissue. In addition, the triglyceride (TG) and cholesterol levels in blood and liver were not changed by addition of Petit vert to a western diet. Moreover, Petit vert significantly increased the excretion of TG and cholesterol, and inhibited the hepatic activity of fatty acid synthase (FAS). These data indicate that Petit vert has the anti-obesitic effect through modulation of lipid metabolism in liver, and the excretion of lipids to feces.

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