Substantial amounts of vitamin B12 were found in some edible algae (green and purple layers) and algal health food (chlorella and spirulina tablets) using the Lactobacillus delbrueckii subsp. lactis ATCC7830 microbiological assay method. Corrinoidcompounds were purified and characterized from these algae to clarify the chemical properties and bioavailability of the algal vitamin B12. True vitamin B12 is the predominate cobamide of green and purple layers and chlorella tablets. Feeding the purple layer to vitamin B12-deficient rats significantly improved the vitamin B12 status. The results suggest that algal vitamin B12 is a bioavailable source for mammals. Pseudovitamin B12 (an inactive corrinoid) predominated in the spirulina tablets, which are not suitable for use as a vitamin B12 source, especially for vegetarians.
We have previously shown that α-tocotrienol (α-T3), a vitamin E analogue and HMG CoA reductase (HMGR) inhibitor, markedly inhibited monocyte-endothelial cell adhesion, a process that was reversed with the addition of mevalonate intermediates involved in protein prenylation. Since δ-T3 and γ-T3 possess greater HMGR inhibition than α-T3, we postulated that these analogues might have a greater effect on protein prenylation, and thus on monocyte adhesion and endothelial adhesion molecule expression in comparison to α-T3. Hence, we pursued to investigate the effect of various analogues of tocotrienol (α, γ, δ) on monocytic cell adhesion and expression of adhesion molecules using a human umbilical vein endothelial cell-line, EA.hy926, as the model system. Relative to α-T3, δ-T3 displayed a more profound inhibitory effect on monocytic cell adherence using a 15, imol/L concentration within 24h (δ: 42±5%; α: 26±8% vs. control). This inhibitory action was reversed by coincubation with farnesol and geranylgeraniol, suggesting a role for prenylated proteins in the regulation of monocyte adhesion. To further evaluate the effect of tocotrienols on the vascular endothelium, we measured the surface expression of adhesion molecules. Compared to α-T3, δ-T3 markedly inhibited the expression of VCAM-1 (δ: 57±6%; α: 37±10% vs. control) and E-selection (δ: 36±3%; α: 18±6% vs. control) in TNF-α activated endothelial cells. The above result suggests that δ-T3 is a potent and effective agent for the reduction of cellular adhesion molecule expression and monocytic cell adherence.
The iron trend in the serum of male rats fed a low wheat gluten (5% level) diet containing several fish oils for 2 to 4 wk was investigated. The body weight in every experimental group decreased during the first 3 d and thereafter their body weights dropped gradually until the 4th week. At the end of the experimental period, the weights of the spleens from the rats in the cod liver oil (CLO) and sardine oil (SO) groups were significantly heavier than those of the corn oil (control; CO) group. The iron concentrations in the serum of all dietary groups at the 4th week had a tendency to decrease compared to that of the control (CO) group. Ferritin in serum in the 4th week was significantly increased compared to that of the 2nd week for both the CO and CLO groups. However, that of the SO group remained at a low level similar to that measured in the 2nd week. The unsaturated iron binding capacity (UIBC) of the SO group in the 2nd week was significantly higher than that of the control (CO) group. In the 2nd week, the non-heme iron content in the liver was almost equal to the standard value. In the 4th week, however, the non-heme iron in the liver tissues of all dietary groups was significantly increased compared to those of the corresponding groups in the 2nd week. These findings suggest that iron accumulates in the liver.
The prevalence of allergic diseases is high in Japan, even in infants. Their risk for developing allergies is influenced by the antigens in the mother's diet during pregnancy. We hypothesized that, apart from the antigens, hypersensitivity induced through high energy and nutrient intake by mothers during pregnancy may be a factor for allergic diseases in their babies. In this study, we tried to confirm our hypothesis. Allergy histories of parents and their infants, body characteristics and food and nutrient intake were measured by a questionnaire and a food frequency questionnaire, respectively. A total of 2, 642 responses were obtained (return rate, 94.7%). The major allergic diseases in the infants were atopic dermatitis (6.0%), food allergy (3.7%) and bronchial asthma or asthmatic bronchitis (3.2%). About 60% of the infants with allergies had a family history of allergies. Family his-tory of allergy, age of infant, order of birth, head and chest circumferences of infants, BMI of mothers before pregnancy and delivery and intake of lipids (fat and vegetable oil) and vegetables by mothers related positively, and the intake of protein, carbohydrates and milk and its products correlated negatively with allergic diseases in the infants (p<0.05). The results, together with previous reports, suggest that a high intake of energy and lipids (fat and vegetable oil) during pregnancy may accelerate allergic diseases in infants.
The prevalence of obesity and dyslipidemia and the mean frequency of intake of selected dietary factors were studied in 545 participants aged 46-58y and living in three areas in Tanzania. The prevalence of obesity (body mass index of ≥30kg/m2) was 22.5% among women and 5.4% among men, p<0.001. Higher rates of obesity were observed in both men and women in an urban (U) area of Dar. The prevalence of dyslipidemia [(TC-HDL-C)/HDL-C>5] among men was higher in a pastoralists (P) population of the Maasai in Monduli (22.6%) than in Dar (9.6%) and rural (R) Handeni (7.3%, p<0.05). The mean resting energy expenditure (REE) was higher in subjects from the rural and pastoralists populations than in urban dwellers (0.024 kcal/min/kg, p<0.001). The three areas showed different dietary patterns with subjects from the urban area consuming coconut milk (4d/wk, p<0.001) and meat (2.5d/wk, p<0.05), more often than the rural population of Handeni which had the highest consumption of green vegetables (4.2d/wk, p<0.001). Participants from Monduli had the highest consumption of milk per day (1, 219mL/d, p<0.001). A simple correlation analysis showed that body mass index (BMI) correlated positively with the frequency of intake of coconut milk, fish and meat, and negatively with REE and milk consumption. Total cholesterol (TC) was negatively correlated with the frequency of intake of green vegetables, fish and the REE, and correlated positively with meat consumption and BMI in both genders. Independent of other factors, important contributors to obesity and dyslipidemia in this population were dietary factors such as meat (p<0.001) and fish (p<0.05), and a lower REE (p<0.05). These findings suggest that unhealthy diet and lower energy expenditure are important contributors to obesity and dyslipidemia in Tanzania.
Acetyl-CoA synthetase (AceCS), which catalyzes the activation of acetate to produce acetyl-CoA, was found to have a much greater Km value for acetate in liver mitochondria than that in the heart mitochondria of rats, indicating that two different types of AceCS are located in the liver and heart mitochodria. Recently, Fujino et al. reported that mouse heart mitochondrial AceCS, designated AceCS2, was expressed in a wide range of tissues, however, it was apparently absent from the liver. In this study, liver mitochondrial AceCS activity, but not heart AceCS2, was greatly induced in di(2-ethylhexyl)phthalate (DEHP)-treated rats. We purified and characterized the rat liver mitochondrial AceCS. The molecular mass of the enzyme estimated by SDS-PAGE was -58 kDa, which was quite different from that of the heart mitochondrial enzyme, AceCS2. The calculated Km value for the acetate of the partially purified liver enzyme was much greater, being about 100 times that of heart enzyme, AceCS2.
Three experimental diets with varied n-6-to-n-3 fatty acid ratios (120, 40 and 8) were prepared by a suitable blending of safflower oil containing 72.5% linoleic (18:2 n-6) acid and non-detectable levels of α-linolenic (18:3 n-3) acid, and soybean oil having 56.1% linoleic (18:2 n-6) acid and 7.9% α-linolenic (18:3 n-3) acid. These diets were fed to weanling female Wistar/NIN (inbred) rats for 16 wk to assess the impact of altered dietary n-6-to-n-3 fatty acid ratio on erythrocyte membrane (EMS) cholesterol, phospholipids, fatty acid composition and activities of membrane-bound enzymes such as Na+, K+-ATPase, Cat, Mg2+-ATPase and acetylcholinesterase. Activities of total and ouabain-sensitive-ATPases were significantly higher in the erythrocyte membranes of rats fed diets with a n-6-to-n-3 fatty acid ratio of 40 compared to other groups, whereas the erythrocyte membrane-bound acetylcholinesterase was significantly different among the three groups. The highest and lowest activities for this enzyme were observed in the dietary groups with n-6-to-n-3 fatty acid ratios of 8 and 40 respectively. However, the EMS of rats fed diets with a n-6-to-n-3 fatty acid ratio of 40 alone had significantly higher Ca2+, Mg2+-ATPase compared to those of other two groups. Significant increases were observed in absolute amounts of cholesterol, phospholipids and molar ratio of cholesterol to phospholipids in the EMS of rats fed a diet with a very high 18:2 n-6-to-18:3 n-3 fatty acid ratio (120) as compared to those from the dietary group with 18:2 n-6-to-18:3 n-3 fatty acid ratio (40), which had the lowest levels of cholesterol, phospholipids and cholesterol-to-phospholipid molar ratio. On the other hand, the EMS from rats fed a diet with a very low n-6-to-n-3 fatty acid ratio (8) had significantly lower cholesterol and higher proportions of stearic (18:0), oleic (18:1 n-9), eicosapentaenoic (20:5 n-3), and docosahexaenoic acids, and a higher ratio of docosahexaenoic (22:6 n-3) acid-to-α-linoleic (18:3 n-3) acid compared to the EMS from a very high n-6-to-n-3 fatty acid ratio of 120. Although these changes in EM fatty acid profiles were expected of the respective dietary regimens, the observed changes in the activities of membrane-bound enzymes could have resulted from their interaction with membrane cholesterol, phospholipids and fatty aryl chains.
We have demonstrated that the habitual intake of chitosan can decrease bone mass in ovariectomized (OVX) SHRSP rats fed a low-Ca diet (0.1%). In the present study, we examined both the etiology of bone loss induced by dietary chitosan and the preventive effect of vitamin C supplementation. Rats were OVX and maintained on one of the following diets for 6 wk: 10% cellulose (CE), 10% chitosan (CH) or 10% chitosan with sodium ascorbate (CHVC). CH caused a significant reduction in bone mineral density (BMD) and stiffness in femurs and the fourth lumbar vertebrae (L4). There was no significant difference in intestinal Ca absorption between CH and CE, whereas CH intake significantly reduced intestinal P absorption. The bone loss in CH rats was accompanied with an increase in urinary Ca excretion and a decrease in serum Ca as well as a significant increment in serum PTH and 1, 25(OH)2D3. The vitamin D receptor and calcium binding protein D9K mRNAs were also significantly increased in the duodenum of CH rats. Vitamin C supplementation to CH caused an increase in the Ca and P contents of femurs as well as BMD of the L4, with a decrease in urinary Ca excretion. These results indicate that dietary chitosan with low Ca intake possibly induces the loss of bone mass by enhancing urinary Ca excretion rather than by inhibiting Ca absorption, and that vitamin C supplementation could prevent bone loss caused by chitosan through the increment of retained Ca followed by suppression of urinary Ca excretion.
To investigate the effect of dietary chitosan on plasma lipoprotein cholesterol metabolism, male Sprague-Dawley (SD) rats fed a cholesterol-enriched diet containing cellulose (CE) or chitosan (CS) were studied for 2 wk. Lower plasma total cholesterol, low-density lipoprotein (LDL) cholesterol and very-low-density lipoprotein (VLDL) cholesterol were observed in rats fed a diet containing chitosan. In addition, significantly higher high-density lipoprotein (HDL) cholesterol and HDL2 cholesterol were observed in rats after 2 wk of chitosan feeding. Rats fed the chitosan diet had increased triacylglycerol percentages and decreased free cholesterol, cholesteryl ester and phospholipid percentages in VLDL lipid composition. Chitosan significantly decreased the surface lipid proportions and increased the core lipid proportions in VLDL particles. In addition, the ratios of surface lipids to core lipids of the VLDL particles in rats fed a diet containing chitosan were significantly decreased. A significantly lower plasma apolipoprotein B (Apo B) concentration was observed in rats fed the chitosan diet as compared to those fed the cellulose diet. No significant difference in plasma triacylglycerols or glucose levels was observed between the two dietary groups. Results from this study suggest that chitosan may alter the VLDL particle size and also play an important role in the regulation of lipoprotein metabolism in rats.
The effects of the BuOH fraction from mustard leaf in rats subjected to renal ischemia-reperfusion were examined. The elevated serum superoxide anion (O2-) level and renal xanthine oxidase (XOD) activity in rats subjected to 6-h reperfusion following 1-h ischemia significantly and dose-dependently declined after oral administration of the BuOH fraction at doses of 50 and 200 mg/kg body weight/d for 10 d prior to ischemia-reperfusion. These findings indicate that this fraction might scavenge O2- or inhibit the generation of O2- through XOD activated by the ischemia-reperfusion process. In addition, the thiobarbituric acid-reactive substance level of the renal mitochondrial fraction of rats given the BuOH fraction orally was significantly lower than that of control rats given physiological saline (vehicle), implying that this fraction exerted protective action against lipid peroxidation caused by ischemia-reperfusion. Furthermore, oral administration of the BuOH fraction reduced the serum urea nitrogen and creatinine levels, indicators of renal function. These results suggest that the BuOH fraction has protective effects against ischemia-reperfusion injury, acting as an antioxidant by scavenging O2-, inhibiting O2- generation through XOD, protecting against lipid peroxidation and ameliorating renal functional impairment.
We prepared a novel type of milk calcium from milk whey, and evaluated its calcium bioavailability as compared with conventional industrial milk calcium obtained from milk whey, which has been reported to be an excellent calcium source. An X-ray diffraction analysis showed that the chemical form of conventional industrial milk calcium from milk whey through the neutralization and precipitation method (NP-MCa) is hydroxyapatite type, and that of a novel type of milk calcium obtained using the ultrafiltration method (UF-MCa) is different from hydroxyapatite. Growing rats were fed either NP-MCa or OF-MCa as the source of calcium for 33d. The calcium absorption rate in the OF-MCa diet group was significantly higher than that in the NP-MCa diet group. The calcium content of the femur in the OF-MCa diet group was significantly higher than that in the NP-MCa diet group. The breaking force of the excised femur in the OF-MCa diet group was also significantly higher than that in the NP-MCa diet group. The serum calcium level, alkaline phosphatase activity and calcitonin level were not significantly different between the experimental groups, but the PTH level of the serum in the OF-MCa diet group was significantly lower than that in the NP-MCa diet group. These results indicate that the calcium bioavailability of the novel type of milk calcium (UF-MCa) is higher than that of the hydroxyapatite type of milk calcium (NP-MCa).
This study investigated the effect of different timings of milk intake on body iron stores and improvement in the dietary habit of female collegiate rhythmic gymnasts. Subjects took iron tablets at both breakfast and dinner times during a weight-loss period. In addition, subjects ingested low-fat milk twice a day either at breakfast or dinner (group I; n=7), or between meals (group II; n=6) for 3 mo. Blood was collected four times. Red blood cell count, hemoglobin, serum iron, ferritin and erythropoietin concentrations were measured. Subjects completed a dietary survey for three consecutive days before each blood sampling. The mean body fat in both groups I and II was significantly lower after 3 mo than at the start of the study (p<0.01). Red blood cell count and hemoglobin of group I were significantly higher as compared to those of group II (p<0.05). Serum iron concentrations and transferrin saturation values remained unchanged in both groups. Serum ferritin concentrations in group I were significantly higher 3 mo after the start of the study, but this was not observed in group II. Energy and carbohydrate intake in group II, but not in group I, were significantly lower after 3 mo as compared to those after 1 and 2 mo as a result of missing meals. In conclusion, iron-supplemented meals via milk ingestion did not decrease body iron stores and maintained higher body iron stores compared to a diet that included milk intake between meals. Further, milk intake with meals is related to keeping regular meal times and frequency.
To evaluate the bioavailability of selenium (Se) in high-Se yeast (SeY), the digestibility and chemical species of Se in SeY were investigated. Both Se and nitrogen in SeY were readily released into the soluble fraction through trypsin digestion. In a Sephadex G-25 gel chromatography of the trypsin digest of SeY, the range in which Se was eluted was coincident with the range in which peptide fragments were eluted. Se was distributed almost uniformly within the range and there was no fraction that contained Se in a specifically high amount. A proteolytic enzyme extract of SeY was found to contain Se as selenomethionine (74.8%), selenocystine (9.9%), selenite (5.1%) and as at least three unknown Se compounds (10.2%) when analyzed using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). These results indicate that Se in SeY is mainly present as selenomethionine non-specifically incorporated into peptide chains and is highly digestible. Accordingly, it is concluded that the bioavailability of Se in SeY is high.
The effects of a combination of dietary conjugated Linoleic acid (CLA) supplemented with Sesamin on hepatic ketogenesis and triacylglycerol secretion were compared using the livers of rats fed diets containing 1% CLA or linoleic acid (LA) in combination with 0.2% sesamin for 14 d, respectively. The feeding of CLA, as compared to LA, caused a significant reduction in the weight of perirenal adipose tissue but not that of epididymal adipose tissue, and affected neither growth parameters nor hepatic lipid concentration. Hepatic production of ketone bodies was consistently higher in rats fed CLA than in those fed LA, while triacylglycerol secretion was reversed. No significant difference was noted in the hepatic secretion of cholesterol among the groups. Although there was no effect of the dietary combination of CLA with sesamin on adipose tissue weight, hepatic lipid parameters and ketone body production were observed: i.e., triacylglycerol secretion tended to be reduced. These results suggest that the dietary combination of CLA with sesamin may be an effective approach for lowering serum triacylglycerol levels. The decreased hepatic secretion of triacylglycerol is, in part, due to enhanced fatty acid oxidation in the liver.
Regulation of the gene expressions of uncoupling proteins (UCP)-1, 2 and 3 was investigated in the white and brown adipose tissues and skeletal muscle of young and old rats (8-wk-and 8-mo-old, respectively) fed diets containing various fats (hydrogenated fat, corn oil or fish oil) and proteins (casein or soybean) for 1 wk. The mRNA expressions of UCP-1, 2 and 3 were elevated in the white adipose tissues of the young rats fed soybean protein as compared to those fed casein, and that of UCP-2 was also elevated in the brown adipose tissue. The effects of dietary fat type on the expressions were not clear. The UCP-1, 2 and 3 mRNA expressions were markedly reduced in the tissues of the old rats. The UCP-2 expressions were more markedly elevated by dietary soybean protein and reduced by aging than the others, particularly in the white adipose tissue. The expressions of leptin involved in thermogenesis were also reduced by aging. Moreover, in a fasted-refed experiment conducted for the young rats, UCP-2 mRNA induction in the white adipose tissues reached maximal levels at 1 or 2 h and was stimulated by dietary fat or soybean protein. Thus, UCP-2 mRNA expression was markedly affected by diet and aging, particularly in white adipose tissue.
Urinary output of water-soluble vitamins has been used as an indices for vitamin nutrition. It has been pointed out that the coefficient variance of these values is high, especially for niacin catabolites. Thus, we investigated what kinds of stress affect the catabolism using female subjects. The effects of cold exposure (as a typical physical stress), calculation exercise (a typical mental stress) and dark exposure (a typical emotional stress) on the metabolism of niacin were investigated. Of the stresses, cold exposure significantly increased urinary excretory output of the niacin metabolites. The biosynthesis of nicotinamide from Trp seemed to be increased by cold exposure.
Hesperidin (LIES) is a flavonoid contained in citrus fruit peel. We investigated the effects of long-term administration of HES and its newly developed water soluble analogue, glucosyl hesperidin (GHES), to spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). Animals were fed with diets containing HES or GHES (30 mg/d/kg body weight) for 25 wk. While the daily food intake and the body weight of administered rats were not different from those of the non-administered control rats in both SHR and WKY through the experimental period, the blood pressure and heart rate of SHR administered HES or GHES for longer than 15 wk decreased as compared to the control group. The blood pressure and heart rate of WKY were not changed by the long-term administration of HES or CHES. These results suggest that HES and GHES have anti-hypertensive effects on hypertensive animals.
The National Nutrition Survey in Japan (J-NNS), an annual nationwide survey on nutrition and diet of the Japanese people, is reviewed. J-NNS was started in the Tokyo Metropolitan area in 1945 following the end of World War II. The survey area was gradually expanded and became nationwide in 1948. The current survey obtains data from more than 12, 000 persons of approximately 5, 000 randomly selected households. The survey consists of three parts: a physical examination, a dietary intake survey and a dietary habit questionnaire. The physical examination includes anthropometric measurements and a blood test, the dietary intake survey examines nutrient/food intake with a semi-weighed recording method, and the dietary habit questionnaire monitors nutrition/diet-consciousness and dietary habits. In this review, the aim and brief history of the survey are outlined in the first section. The following section, explains its administrative framework, target population, sampling method, annual schedule and question items, focusing on their historical transition. Then the findings of the J-NNS are summarized, which highlights annual changes in the intake of energy, macronutrients, micronutrients and food groups. The current findings of the dietary habit questionnaire are also given in brief.
The National Nutrition Survey is a unique survey that provides nationwide information on nutrient intake in Japan. Descriptive statistical data of nutrient intake, which has not been described in annual reports, are summarized in this report. A dataset from the National Nutrition Survey between 1995 and 1999 was used for analyses. The distribution of vitamin A intake had an extremely long righth-and tail and the difference between mean and median was very large. The results alert us to understand and use statistics properly when one summarizes the data. Means and medians of each nutrient intake except vitamin C were higher in men than in women, however, means and medians of nutrient density (per 1, 000 kcal energy intake) for all nutrients were higher in women than in men. Fat intake was the highest in individuals in their 20s and gradually declined in older age groups. Most of other forms of nutrient intake were the highest in individuals in their 50s or 60s and declined in older age groups. However, a declining trend with aging was not observed in the nutrient density of all nutrients except fat. These statistical data would support better interpretation of the survey data. Furthermore, some methodological limitations in the dietary assessment of the present survey, including the possibility of overestimating nutrient intake by not taking nutrient loss during the cooking process in households into account, were discussed. It is important to use and interpret the survey data under careful consideration on such methodological limitations.