We have previously reported that substantial amounts of tocotrienols were present in the skin of animals fed a diet containing a tocopherols and tocotrienols rich fraction (T-mix) extracted from palm oil, and further, that sesame lignans enhanced tocotrienol levels in the skin. The present studies were undertaken to determine whether dietary tocotrienols and those with sesamin could protect the skin from damage induced by UVB irradiation in hairless mice fed four diets: a vitamin E-free diet, a 50 mg/kg α-tocopherol diet, a 229 mg/kg T-mix (with 50 mg α-tocopherol) diet and a 229 mg/kg T-mix with 2 g/kg sesamin diet. In Experiment 1, mice were fed the diets for 6 wk, and half of the mice were exposed to 180 mJ/cm² of UVB light once daily for 7 d. After the intensity of sunburn was scored, vitamin E and thiobarbituric acid reactive substances (TBARS) concentrations in the skin and liver were determined. In Experiment 2, hairless mice were initiated with a single application of 7, 12-dimethylbenz[a]anthracene (DMBA), then 1 wk later mice were fed the experimental diets and subjected to 180 mJ/cm² UVB irradiation twice weekly for 20 wk. Tumor incidences were counted once a week. Tocotrienols were detected in the skin of mice fed T-mix, but their concentrations were significantly lower than for α-tocopherol. Sesamin elevated tocotrienol contents in the skin. In spite of the high α-tocopherol contents, the effects of α-tocopherol on sunburn and incidence of tumor were slight. T-mix fed groups reduced the extent of sunburn and incidence of tumor, and further reduction of sunburn and incidence of tumor were observed in the T-mix with sesamin group. These results suggest that dietary tocotrienols protect the skin more strongly than α-tocopherol against damage induced by UVB and sesamin enhances tocotrienol effects.

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This study was done to develop a Food Frequency Questionnaire (FFQ) for assessing calcium intake in Vietnamese based on data from the National Nutrition Survey in 2000. From the data, a total of 36 calcium-rich food items were selected for the FFQ by ranking food items according to their contribution to the population intake of nutrients. The FFQ was validated in 140 postmenopausal women by comparing estimates of calcium intake from the FFQ with those from multi-pass 24 h recalls. The results showed that the Pearson correlation coefficient between the 2 methods was 0.84 (p<0.001), and that the weighted kappa value was 0.44. Cross-classification analysis indicated that 82.1% of subjects were classified into the same or adjacent quartile by both methods. No subject was grossly misclassified by the FFQ. There is no significant difference of calcium intake between the 2 methods (by paired t test, p>0.05). A reproducibility study also presented good correlation between 2 administrations of the FFQ, with Pearson correlation coefficient being 0.93 (p<0.001) and weighted kappa value being 0.67. In conclusion, this FFQ is useful and reliable for estimating calcium intake in population-based epidemiological studies in postmenopausal Vietnamese women.

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Cellular retinol-binding protein type II (CRBPII) is exclusively expressed in the small intestinal absorptive cells. We previously reported that dietary fat induces CRBPII expression within 12 h of fat intake. To examine at which locus of the villus-crypt axis this response to dietary fat occurs, 6-wk-old rats were fed a low-fat diet (7% energy) for 7 d, and then given free access to a high-fat diet (70% energy) for the subsequent 12, 24 or 48 h. Cryostat sectioning of jejunal segments followed by RNA blot hybridization of the transcripts revealed that CRBPII mRNA was expressed maximally in the lower villus, and the immunoreactive protein of CRBPII was expressed maximally in the mid-villus. Feeding the high-fat diet caused a pronounced increase in CRBPII mRNA level from the lower- to middle-villus within 12 h. These results suggest that the CRBPII gene is maximally expressed in the lower villus, and that dietary fat causes an enhancement of CRBPII gene expression in the villus cells.

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Previous studies indicated that a medium-chain triacylglycerol (MCT) diet could inhibit body fat accumulation. It is also well established that exercise can reduce fat mass. However, the effects of a combination of MCT diet and exercise on reduction of fat mass have not been studied. Here we examined whether MCT diet and exercise intervention exert cooperative effects on body composition. Rats were assigned to 4 groups: 1. LCT diet, control (LCT-C); 2. MCT diet, control (MCT-C); 3. LCT diet, exercise (LCT-E); 4. MCT diet, exercise (MCT-E). After the 6-wk intervention, visceral fat mass was measured by CT scan and dissection, and energy expenditure was estimated for 24 h. The value of the visceral fat mass showed a significant correlation between CT scan and dissection (r=0.995, p<0.001). Visceral fat mass in the MCT-C group was lower than that in the LCT-C group. Furthermore, the fat-lowering effects were greater in the MCT-E group than that in either intervention alone. Thus significant effects of the MCT diet and exercise on the reduction of visceral fat mass were observed. Energy expenditure was significantly higher in the MCT-E group than in the other groups. Our present findings suggest that combined intervention of MCT diet and exercise has an additive effect on reduction of visceral and subcutaneous fat accumulation, and that this effect may be partially related to increased energy expenditure. However, future studies are necessary to define the relationship between energy expenditure and fat mass accumulation.

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Our recent study demonstrates that polypyrimidine tract-binding protein (PTB), which is a sequence specific RNA-binding protein, attenuates albumin synthesis in a cell-free translation system. In this study, the effects of food intake on regulation of albumin synthesis through binding of PTB to albumin messenger RNA (mRNA) were investigated. Rats were divided into 1 of 3 groups: fed; fasted for 36 h; or fasted for 36 h and then refed for 24 h. No significant differences in albumin mRNA levels were found among fed, fasted and refed rats. However, a decrease in the proportion of albumin mRNA associated with polysomes was identified in fasted rats. Furthermore, UV-cross linking analysis demonstrated that levels of albumin mRNA-PTB complex were increased in liver extracts from fasted rats. No significant differences in PTB levels in liver homogenate were found among the experimental groups. However, PTB level in the cytoplasmic fraction was higher in fasted rats than in fed rats. In refed rats, PTB level in the cytoplasmic fraction returned to a level comparable to that in fed rats, but was inhibited by treatment with rapamycin, a mammalian target of rapamycin (mTOR) inhibitor. These results suggest that localization of PTB is regulated by food intake through mTOR signaling, and alterations in level of albumin mRNA-PTB complex play a role in mediating the effects of food intake on albumin synthesis in the rat liver.

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Background: Ginseng, oriental bezoar and glycyrrhiza are the most widespread herbs often used in Kampo. These three herbs have been used for a Kampo for a thousand years and a number of pharmacological and clinical studies have reported about their effects. However, it has not been previously described how the combination of these most commonly used herbs affects the autonomic nervous system (ANS). Objective: This is a randomized, double-blind, placebo-controlled experiment to examine the acute effects of Kampo on autonomic nervous activity by using power spectral analysis of heart rate variability (HRV) and cardiac depolarization-repolarization time intervals in humans. Design: Ten healthy men volunteered to participate in this study. The Kampo at a dose of two capsules contained the following ingredients: powdered ginseng 250 mg, powdered oriental bezoar 50 mg, and powdered glycyrrhiza 50 mg. The placebo capsules contained corn starch. A CM5 lead ECG was recorded before, and 30 min and 60 min after the oral administration of Kampo or a placebo on different days. Results: HF power (high frequency component in the HRV) was significantly increased and HR (heart rate) was significantly decreased after taking Kampo at 60 min (p<0.05) compared with the placebo. TP (total power) and LF power (low frequency component in the HRV) did not change significantly between the Kampo and placebo, and there were also no statistically significant differences in heart-rate-corrected ECG QT interval (QTc) or recovery time (RTc) between the Kampo and placebo. However, we observed that there was a tendency of decreased QTc interval and RTc after taking Kampo at 60 min compared with response of the placebo (p<0.1). Conclusions: These results indicated that the Kampo mainly potentiated parasympathetic nervous activity and may be useful for cardiovascular health.

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This study was undertaken to investigate the effects of isoenergetic and increased amounts of egg white protein one hour before a run on the changes in the post-exercise blood biochemistry and the rating of the perceived exertion (RPE). Twenty-four male distance runners were divided into four groups. Venous blood samples were collected at three time points: just before the experiment (Pre), just after a 12,000 m run (Post 0 h) and one hour after the run (Post 1 h). After the first blood sampling, each participant consumed one of the four isoenergetic supplements (86 kcal); 0 g, 5 g, 10 g, or 20 g of egg white protein. The blood glucose, free amino acid, and branched chain amino acid (BCAA) levels in the 0 g, 5 g, and 10 g protein groups were higher at Post 0 h than at Pre. The pre-exercise intake of the 20 g protein group showed the smallest changes in the blood biochemicals. The RPE scores were significantly higher at Post 0 h, and did not vary among the four protein groups. Accordingly, the pre-exercise carbohydrate intakes significantly altered the post-exercise blood biochemisty findings, but the pre-exercise protein intake did not. Furthermore, the changes in the RPE scores in our present study were not explained by changes in the serum free tryptophan or the BCAA levels, and an increased dietary intake of egg white protein might not prevent post-exercise increases in the RPE scores.

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White rice (WR) is made by polishing brown rice (BR) and has lost various nutrients; however, most people prefer it to BR, maybe because of the hardness of BR. Pre-germinated brown rice (PGBR) improves the problem of BR. It is made by soaking BR kernels in water to germinate and becomes softer than BR. In this study we compared the effects of WR and PGBR on blood glucose and lipid concentrations in the impaired fasting glucose (IFG) or type 2 diabetes patients. Six men and 5 women with impaired fasting glucose (IFG) or type 2 diabetes were randomly allocated to 6 wk on WR or PGBR diet separated by a 2 wk washout interval in a crossover design. Each subject was instructed to consume 3 packs of cooked WR or PGBR (180 g/pack) daily in each intervention phase. Blood samples were collected 4 times (in study weeks 0, 6, 8 and 14) for biochemical examination. Blood concentrations of fasting blood glucose, fructosamine, serum total cholesterol and triacylglycerol levels were favorably improved on the PGBR diet (p<0.01), but not on the WR diet. The present results suggest that diets including PGBR may be useful to control blood glucose level.

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Over-concern about thinness, especially among young girls including adolescents, is common in Japan. Behind the problem, there is a complicated social phenomenon and an effective strategy is not known yet. In this study, we tried to find a clue by comparing body image between two countries which have different social backgrounds. Subjects were Japanese and Vietnamese junior high school students from 12 to 15 y old. Three schools each and 1-2 classes from each grade were randomly selected to involve 374 (boys 196, girls 178) and 714 (boys 352, girls 362), respectively, in Japan and Vietnam. Height and weight of subjects were measured and their satisfaction about their body shape and experience with dieting were asked by a questionnaire. Questions about their body image concerning their desire, liking of the opposite sex, own liking and health were answered by marking silhouettes. About 60% of Japanese thought that obese (silhouette 9) is unhealthy, while about 85% of Vietnamese thought that thinness (silhouette 1) is unhealthy. Most of the Japanese girls overestimated their body weight and were dissatisfied with their body shape and 78.3% wanted to lose weight. About 30% of them experienced weight loss including 2.8% of the low BMI students. Vietnamese girls also had similar tendencies in their desire about their body image as the Japanese but they were less serious. The girls in both countries preferred the thinner body image to the healthy body image and thought that boys liked the thinner body image. Japanese boys were mostly satisfied with their body shape; however, about half (46%) of the Vietnamese boys wanted a bigger and more muscular body image. In conclusion, the biggest problem with body image was the over-concern about thinness of the Japanese girls, which was based on their own misconception. Therefore, as the strategy to correct their body image, education about good health and also information about the boys' favorite body image are recommended.

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The combined effects of dimethylsulfoniopropionate (DMSP) (10⁻³, 10⁻⁴ and 10⁻⁵ M) with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (5 ng/mL) and the nerve growth factor (NGF) (5 ng/mL) on the outgrowth and elongation of neurites from pheochromocytoma (PC12) cells were examined on RPMI medium containing fetal bovine serum and horse serum with penicillin and streptomycin in collagen-coated dishes for 5 d. The growth was higher in increasing order of the DMSP (10⁻³ M), MPTP and NGF, the DMSP (10⁻⁵ M), MPTP and NGF, the MPTP and NGF group and the control group up to 3 d, but not in the NGF and the DMSP (10⁻⁴ M), MPTP and NGF groups. The growth in all the experimental groups showed plateaus from days 4 to 5. The appearance of neurites from the cells in all the groups showed maxima on the 3rd day. The administration of NGF significantly stimulated the outgrowth of neurites from the cells, while the supplementation of MPTP noticeably inhibited the appearance of neurites even in the presence of NGF up to 5 d. However, the addition of DMSP (10⁻³ and 10⁻⁴ M) to the latter group completely prevented the inhibition of the MPTP. These facts were significantly supported by the photographs of neurite-bearing cells on the 3rd day and also by the photometric analyses examining the reaction of MPTP to DMSP, NGF or Collagen IV.

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Dahl salt-sensitive (Dahl-S) rats, serving as a model of hereditary hypertension, were used to examine the effect of mannooligosaccharides (MOS) on blood pressure. Dahl-S rats were induced to develop hypertension by administering them with a 1.25% salt solution ad libitum. In a 10-wk experimental period, the Dahl-S control and MOS groups developed and maintained significantly higher blood pressure than the Dahl salt-resistant normal control group. The MOS group showed a significantly lower blood pressure than the Dahl-S control group after 5-wk of treatment (p<0.05). In addition, the serum aldosterone level of the MOS group significantly decreased (p<0.05). The findings of this study using a model of hypertensive rats suggest that MOS are able to suppress an elevation in blood pressure.

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