Cytokeratin (CK) 18 M30 antigen has been proposed as a diagnostic marker of nonalcoholic fatty liver disease (NAFLD). We studied serum CK18 M30 antigen level and examined the correlations among CK18 and biological data, dietary intake, and plasma fatty acid composition in middle-aged Japanese males with (NAFLD; n=42) and without NAFLD (control; n=35). NAFLD was diagnosed if subjects showed fatty liver on abdominal ultrasonography and their alcohol consumption was <20 g/d. They were also confirmed to have negative serological results for tests of autoimmune liver disease and hepatitis B and C. In the NAFLD group, body mass index, waist circumference, serum M30 antigen, alanine transaminase (ALT), cholinesterase, triacylglycerol, LDL-cholesterol, and HbA1c were significantly higher than in the control group. In the fatty acid analysis of plasma phospholipids, significantly higher dihomo-γ-linolenic acid (DGLA), total saturated fatty acids (SFA), and palmitic/linoleic acid ratio as well as lower arachidonic acid/DGLA ratio were observed in the NAFLD group compared with the control group. In the NAFLD group, M30 antigen was correlated positively with serum ALT, plasma DGLA, dietary SFA, and serum TNF-α as determined by partial correlation analysis controlled for BMI. On the basis of multivariate regression analysis using a stepwise method, M30 antigen was significantly associated with ALT and plasma DGLA. Regarding the determinants of NAFLD as revealed by logistic regression analysis, a high odds ratio was observed for plasma DGLA. In conclusion, members of the NAFLD group showed higher levels of serum CK18 M30 antigen and M30 antigen was strongly associated with serum ALT and plasma DGLA. Abnormal fatty acid metabolism may be a factor that causes aggravation of NAFLD.

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The present study estimated the dietary intake of seven B vitamins using a total diet study (TDS) in Japan. The daily intake of vitamins estimated by TDS was calculated based on the mean contents of vitamins in 18 food groups, and the amount of food intake in the Nation Health and Nutrition Survey in Japan, 2006. The estimated daily intake of these vitamins for all ages was 22.8 mg NE/d for niacin, 7.4 μg/d for vitamin B₁₂, 146 μg/d for folic acid, 4.52 mg/d for pantothenic acid, 1.06 mg/d for riboflavin, and 1.44 mg/d for pyridoxine. The estimated daily intake of the vitamins of niacin, vitamin B₁₂ and pyridoxine exceeded the dietary reference values for adults aged 18-29 y. The estimated daily intake of these vitamins by TDS was higher than the daily intake reported in the National Health and Nutrition Survey in Japan, 2006. There was a strongly positive correlation between the intake levels estimated by TDS and those reported in the National Health and Nutrition Survey. This suggests that TDS is an effective dietary survey for estimating the dietary intake of water-soluble vitamins. Therefore, when being determined by TDS, the estimated daily intake of biotin was 51.0 μg/d for all ages.

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Pre-germinated brown rice (PR) has been developed industrially in order to enhance the nutritional functions of its source material, brown rice (BR). The present study was aimed at clarifying the effect of PR on the type 2 diabetes mellitus. We employed Otsuka Long-Evans Tokushima Fatty (OLETF) rats as a model of type-2 diabetes mellitus. OLETF rats were fed on either PR or white rice (WR) from the age of 4 to 35 wk. Age-matched male Long-Evans Tokushima Otsuka (LETO) rats as a non-diabetic control were also fed on WR. The HbA_1c level in OLETF rats was significantly higher than that in LETO rats. However, the level was lower in PR-fed OLETF rats than in WR-fed OLETF rats. The plasma concentrations of TNF-α and PAI-1 in OLETF rats were higher than those in LETO rats. However, both elevated levels were decreased by the PR-feeding, but not by the WR-feeding. On the other hand, the plasma adiponectin concentration in OLETF rats was lower than that in LETO rats. The decrease in adiponectin level of OLETF rats was ameliorated by PR-feeding. The size of adipocytes in PR-fed OLETF rats was smaller than that in WR-fed OLETF rats. In summary, intake of PR instead of WR ameliorates both insulin resistance and imbalance of the levels of plasma adipocytokines leading to diabetic complications.

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In Japan, the number of low weight birth babies is increasing. The increase in the number of slim young women is considered to be associated with the rising number of low birth weight babies in Japan. In 1993, Barker et al. published highly influential findings indicating a relationship between low birth weight and increased risk of developing symptoms of metabolic syndrome. Here, we report on results that occur when dietary restriction is applied during all periods of pregnancy. It was shown that, at 5 d, the mean weight of pups in the dietary restriction group was lower than the mean weight of pups in the control group. Catch-up growth began when milk yields of the dietary restriction group pups attained the same levels as those of the control group pups. Intra-abdominal adipose tissue weights of the dietary restricted group were significantly higher than those of the control group in males at 280 d after birth. Intra-abdominal adipose tissue weights of the dietary restricted group had a tendency to be higher than those of the control group for female rats. In male rats, it is considered that increase in intra-abdominal adipose tissue is related to lean body mass but it is not related to the function of brown adipose tissue (BAT). In female rats, it is considered that the increase in intra-abdominal adipose tissue is related to the function of BAT and lean body mass.

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The purpose of this study was to elucidate the fat-loading effect of the classic 1-wk glycogen-loading regimen histologically in rats and physiologically in humans. In the rat and human studies, an exhaustive swimming exercise and cycle ergometer exercise were loaded on day 1 of a 6-d feeding period, respectively. Thereafter, both the rats and humans were divided into a glycogen-loading regimen consisting of a 3-d high-fat diet and a 3-d high-carbohydrate diet or a 6-d high-carbohydrate diet. After the feeding period in the human study, the human subjects performed a test exercise on day 7 using a cycle ergometer. In the rat study, the intramuscular triglyceride (IMTG) content was 69% greater (p<0.05) after the glycogen-loading regimen than after the high-carbohydrate diet feeding on day 7. In the human study, the respiratory exchange ratios (RER) after the glycogen-loading regimen were 4.9-6% lower than those after the high-carbohydrate diet during the test exercise on day 7 (p<0.05). Our findings suggest that the classical 1-wk glycogen-loading regimen maintained the storage and enhanced the utilization of energy sources during exercise in the skeletal muscle, and that it provides a fat-loading effect, in addition to the glycogen-loading effect, to the skeletal muscle.

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We measured concentrations of sodium and creatinine in previously validated overnight urine and 24-h urine of 79 healthy infants of 3 to 5 y of age in two cities in Miyagi Prefecture, Japan. Thereafter, we estimated daily salt intake from daily urinary sodium excretion and daily urinary volume. Corrections for potential sweat loss of sodium chloride were conducted based on urinary volume and urinary creatinine concentration. We also measured urinary volume and urinary sodium concentration in infants who failed to provide complete urine samples. The estimated salt intake did not differ between boys and girls, but varied between the two cities. The estimated salt intake per unit of body weight differed neither between genders nor between cities. The grand means for estimated salt intake and that per unit of body weight were 5.5 g/d (SD 1.8) and 0.32 g/kg/d (SD 0.10), which supported previous results both in Japan and abroad. It was also possible to roughly estimate salt intake from sodium concentration in overnight urine or incomplete 24-h urine, and published urine volume.

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The purpose of this study is to determine the anticancer activity and the nutritional values of the seeds of Glinus lotoides, a plant used as a dietary vegetable and medicinal plant in Asia and Africa. To achieve this goal, the seeds were extracted in soxhlet using solvents, namely n-hexane, dichloromethane, methanol and water. The methanol and n-hexane extracts showed differential growth inhibitory responses in carcinoma cell lines (Calu-3 IC₅₀=29.7 and 79.8 μg/mL and Caco-2 IC₅₀=69.7 and 74.6 μg/mL, respectively) as compared to normal cell lines (MDCK IC₅₀=106.1 and 131.1 μg/mL and IEC-6 IC₅₀=134.0 and 128.5 μg/mL, respectively). In addition, these extracts induced significant apoptosis in the cancer cells (p<0.05) at 100 μg/mL. The seeds of G. lotoides were found to contain nutritional compounds of well-established chemopreventive activity, including vitamin E, folic acid, selenium and calcium. The hydrophilic oxygen radical absorption capacity (ORAC) value was found to be 123 μM Trolox Equiv./g, indicating the antioxidant activity of the plant. These data suggest that the seeds of G. lotoides could potentially be used in the diet in chemoprevention of cancer and warrant further confirmatory preclinical and clinical studies. The amount of protein, carbohydrate, fat, ash, moisture, sugar profile and fatty acids further support the nutritional value of the seeds.

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We have shown that the rate of brain protein synthesis in aged rats depended on the quality and quantity of dietary protein consumed. The purpose of this study was to determine whether the quality and quantity of dietary protein affected the phosphorylation of eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase (S6K1) and regulated the brain protein synthesis. Two experiments were done on three groups of 24-wk-old male rats given diets containing 20% casein, 20% gluten, or 20% gelatin (Experiment 1), and 20% casein, 5% casein or 0% casein (Experiment 2) for 10 d. The phosphorylation of S6K1 in both the cerebral cortex and cerebellum, and the phosphorylation of 4E-BP1 in the cerebral cortex declined with a decrease of quality and quantity of dietary protein. The phosphorylation of 4E-BP1 in the cerebellum did not differ among groups. The results suggest that the ingestion of a higher quality and quantity of dietary protein stimulates the phosphorylation of 4E-BP1 and S6K1 in the brain and increases the brain protein synthesis in the aged rats.

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Vitamin D receptor (VDR) is a nuclear receptor that regulates the expression of genes involved in calcium homeostasis. Activation of VDR is thought to be a promising drug target for osteoporosis. Using a VDR-driven luciferase expression assay for screening a naturally occurring food component, we identified quercetin as a VDR activator. Quercetin also activated the GAL4 DNA-binding domain fused to the VDR ligand-binding domain. Moreover, it was confirmed that quercetin increases the mRNA level of TRPV6, which is a VDR target gene, in Caco-2 cells. These results indicate that quercetin enhances VDR activity through the alteration of cofactor recruitment, thereby stimulating its target genes while providing a new function for quercetin as the VDR activator.

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The major catechins of green tea extract are (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECg), and (−)-epigallocatechin gallate (EGCg). Recent research has indicated that catechins form complexes with human serum albumin (HSA) in blood, and differences in their binding affinity toward HSA are believed to modulate their bioavailability. In this study, we kinetically investigated the interaction between the catechins and HSA immobilized on a quartz-crystal microbalance (QCM). The association constants obtained from the frequency changes of QCM revealed interactions of ECg and EGCg with HSA that are 100 times stronger than those of EC and EGC. Furthermore, comparisons of these catechins by native-gel electrophoresis/blotting with redox-cycling staining revealed that, in a phosphate buffer, ECg and EGCg have a higher binding affinity toward HSA than EC and EGC. These observations indicate that catechins with a galloyl moiety have higher binding affinities toward HSA than catechins lacking a galloyl moiety.

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