|
| O. Mora, J.L. Romano, E. Gonzalez, F. Ruiz and A. Shimada Low Cleavage Activity of 15,15'dioxygenase to Convert b-carotene to Retinal in Cattle Compared with Goats, is Associated with the Yellow Pigmentation of Adipose Tissue |
Zusammenfassung Summary |
| Misao Takasaki, Hiromi Inaba, Atsutane Ohta,
Yasuko Motohashi, Kensuke Sakai, Howard Morris and Keiko Sakuma Dietary Short-Chain Fructooligosaccharides Increase Calbindin-D9k Levels Only in the Large Intestine in Rats Independent of Dietary Calcium Deficiency or Serum 1,25 Dihydroxy Vitamin D Levels |
Zusammenfassung Summary |
| Jürgen Koenig and I. Elmadfa Status of Calcium and VitaminD of Different Population Groups in Austria |
Zusammenfassung Summary |
| Judy A. Driskell2, David W. Giraud
and Susan H. Mitmesser Vitamin B-6 Intakes and Plasma B-6 Vitamer Concentrations of Men and Women, 19-50 Years of Age |
Zusammenfassung Summary |
| Dorothee Brubacher, Ulrich Moser, and Paul
Jordan Vitamin C Concentrations in Plasma as a Function of Intake: a Meta-analysis |
Zusammenfassung Summary |
| Thomas Frank, Marco Kühl, Beate Makowski,
Roland Bitsch, Gerhard Jahreis and Johanna Hübscher Does a 100-km Walking Affect Indicators of Vitamin Status? |
Zusammenfassung Summary |
| Sun-Young Lim and Hiramitsu Suzuki Effect of Dietary Docosahexaenoic Acid and Phosphatidylcholine on Maze Behavior and Fatty Acid Composition of Plasma and Brain Lipids in Mice |
Zusammenfassung Summary |
Zusammenfassungen / Summaries
Summary
Two experiments (one with twelve heifers and the other with 14 goats) were designed to evaluate the effect of increasing dietary b-carotene concentration on the activity of the cleaving enzyme 15,15'b-carotene dioxygenase and the concentration of b-carotene and retinol in selected tissues. The experiments lasted 120 days. During the first 90 days animals were offered a b-carotene unsupplemented diet. In the following 30 days, they were distributed to one of three treatments: 0, 5.5 or 352 mg of b-carotene/kg of dry matter intake. All animals were slaughtered at the end. In heifers the concentration of b-carotene in plasma, reflected the level of b-carotene fed. Goats had detectable levels of b-carotene only on day 10 of supplementation. In the liver, b-carotene concentrations were highest with the 352 dose in both species. Heifers had the highest concentration of b-carotene in the adipose tissue. In bovines, no interaction between b-carotene treatment and intestinal sampling site was found (P > 0.2) for the activity of 15,15 dioxygenase. Across b-carotene levels, results of the enzyme assay were: 0.19, 0.32 and 0.45 nmol retinal/(mg S-9 protein/h) (P < 0.01) for 0, 5.5 and 352 mg b-carotene·kg dry matter intake 1·d1, respectively; across intestinal sampling sites results of the enzyme assay were 0.45, 0.43 and 0.08 nmol retinal/(mg S-9 protein/h) (P < 0.01) for duodenum, jejunum and ileum, respectively. Caprine data showed an interaction between b-carotene treatment and intestinal sampling site (P < 0.05) for the activity of 15,15 dioxygenase. The results for treatment 0 were: 1.4, 1.4 and 0; for treatment 5.5: 1.41, 1.42 and 0.13; and for treatment 352: 1.46, 1.99 and 0.48 nmol retinal/mg S-9 protein/h for duodenum, jejunum and ileum, respectively. The lower levels of duodenal and jejunal 15,15'dioxygenase activity in cattle compared with goats, may explain the greater pigmentation of adipose tissue in the former ruminant specie.
Key words
Angus heifers, goats, b-carotene, dioxygenase cleavage
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
Dietary short-chain fructooligosaccharides (Sc-FOS) increase mucosal calbindin-D9k (CaBP) levels in the large intestine whereas levels in the small intestine are decreased in rats. In the present study, we investigated the mechanism by which Sc-FOS induce this increase in CaBP in the large intestine by measuring intestinal CaBP levels in rats fed normal and calcium-deficient diets. Dietary groups included a calcium-containing (0.5%) diet with or without Sc-FOS (100 g/kg diet) and a calcium-deficient (abt. 0.01%) diet with or without Sc-FOS (100 g/kg diet). The rats were fed these diets for 10 days following which they were killed and the intestine removed for collection of the entire mucosa which was divided into four segments, i.e., proximal and distal segments of the small intestine, the cecum and the colorectum. Mucosal CaBP and plasma calcium (Ca), 1,25-dihydroxycholecalciferol (1,25(OH)2D3), 25-hydroxycholecalciferol (25(OH)D3), parathyroid hormone (PTH) and calcitonin levels were measured. Feeding of calcium deficient diet resulted in an increase in CaBP levels in the small intestine, but did not influence levels in the large intestine. Moreover, a significant positive correlation between plasma 1,25(OH)2D3 and CaBP levels in the case of both small intestinal segments (proximal, r = 0.77012, p < 0.00007; distal, r = 0.75056, p < 0.00014) was observed, but not in the case of the large intestinal segments. Sc-FOS increased CaBP levels in the large intestine. These results suggest that the large intestinal CaBP levels do not change in response to dietary calcium conditions and are not regulated by circulating 1,25(OH)2D3 indicating that the effect of Sc-FOS on CaBP levels in the large intestine is independent of the action of 1,25(OH)2D3.
Key words
Fructooligosaccharides, vitamin D, calbindin-D9k, calcium, rats
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
Vitamin D and calcium are essential for bone metabolism and
the status of both nutrients is discussed in relation to osteoporosis
and osteoporosis-related disorders. Thus, it is important to monitor
the status of these nutrients in the population to early recognise
insufficiences and to establish preventive measures. Intakes of
calcium and vitamin D have been evaluated in different Austrian
population groups (pre-school children, school children, adolescents,
adults, elderly, pregnant and lactating women) by dietary records
(3 d and 7 d weighed records, 24 h recalls). From pre-school children,
school children, elderly, pregnant and lactating women fasting
blood and spontaneous urine samples were collected and analysed
on concentrations of calcium in serum and urine (adjusted to creatinine)
and of 25-OH-cholecalciferol in serum.
Average calcium intake (834 ± 422 mg/d) below the specific
recommended allowances of the according age group were found for
58% of the total population with the highest incidence of low
supply in adolescents at 1519 years of age and adults at
46-65 years of age. Vitamin D intakes (2.1 ± 1.4 mg/d)
were even lower with 68% of the total population being not able
to meet the recommendations. Again, adolescents at 15-19 years
showed the highest incidence of insufficient vitamin D intakes.
Calcium concentrations in serum were satisfying for children and
adolescents. Vitamin D status was found below the reference range
(15 nmol/l) for 50% of all samples with the highest frequency
in elderly people. Basing on the applied method for the determination
of 25-OH-cholecalciferol concentrations a reference range for
the Austrian population is suggested.
The results show that low intakes of calcium and vitamin D lead
to decreased status of these nutrients especially for adolescents,
elderly, pregnant and lactating women, indicating the highest
risk for the development of disorders of bone metabolism in these
groups.
Key words
Vitamin D, 25-OH-cholecalciferol, calcium, intake, status, pre-school children, school children, adolescents, adults, elderly, pregnancy, lactation, reference range
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
The vitamin B-6 intakes and plasma B-6 vitamer levels of healthy nonsupplemented men and women, 19-24 and 25-50 years, were compared. The subjects did not take nutrient supplements or medications or use tobacco products. Subjects were grouped as follows: eight, 19-24 y men; nine, 25-50 y men; 11, 1924 y women; and 13, 2550 y women. The estimated vitamin B-6 intakes, obtained via 24-h recalls followed by 2-d food records, of the two groups of men were significantly higher (P < 0.05) than those of the two groups of women. Thirty-five percent of the women reported consuming less than the Estimated Average Requirement for vitamin B-6. The four gender: age groups had similar B-6 vitamer concentrations of plasma pyridoxal-5'-phosphate, 4-pyridoxic acid, pyridoxine, pyridoxamine, and pyridoxamine-5'-phosphate. Males 25-50 y had significantly higher (P < 0.05) plasma pyridoxal concentrations than the two groups of females. All subjects had pyridoxal-5'-phosphate concentrations indicative of vitamin B-6 adequacy. Generally the plasma B-6 vitamer concentrations of these men and women, 19-24 and 25-50 years of age, all having adequate vitamin B-6 status, were similar.
Key words
Vitamin B-6, plasma B-6 vitamers, pyridoxal phosphate, men, women
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
The purpose of this study was to estimate the intake plasma relationship for vitamin C by means of a meta-analysis. A MEDLINE search revealed 30 publications matching our inclusion criteria. We completed the set with 5 older papers and with one monograph. The proposed statistical model corrects for inconsistencies with regard to methodological differences between the various studies. Therefore, the contribution of a particular study to the estimation is independent of the number of data points. The estimations were performed for the complete data set as well as for different subgroups: "adult" aged 1565 years, "elderly" aged 6096 years, "nonsmokers" and "smokers". The 50th percentile of the plasma concentration for a daily vitamin C intake of 60 mg was 42.4 mmol/L. The corresponding values for the different subgroups were: "adult" 44,1 mmol/L, "elderly" 31.0 mmol/L, "nonsmokers" 42,4 mmol/L, and "smokers" 33.6 mmol/L. Thus, this meta-analysis confirms earlier results that the requirements of vitamin C is higher in "elderly" and "smokers" compared to "adult" and "nonsmokers" and it can be used for the estimation of the vitamin C intake in order to achieve a desired plasma level within a target population. In the general population the assumed optimal plasma concentration of 50 mmol/L, as proposed by a consensus conference, can be achieved by the intake of 100 mg per day, which is the new recommendation of the Austrian, German, and Swiss Nutrition Societies.
Key words
Meta-analysis, vitamin C, intake, plasma concentration
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
The status of thiamin (B1), riboflavin (B2), ascorbic acid (AA), and tocopherol was determined in 60 leisure athletes (age 46 ± 10 y, BMI 23.7 ± 2.0 kg · m-2, VO2max 39.4 ± 6.5 ml · min-1 · kg-1), who completed a 100-km walking race. Vitamin plasma levels and activities of erythrocyte transketolase (ETK) and glutathione reductase (EGR) were measured before start, immediately after finishing and 6 hours later. The participators finished the entire distance in 14.25 h (average speed 7 km·h-1). Before start, all participators showed an excellent vitamin status (prevalences of low vitamin status ranged between 1.7 and 1.8%). Plasma tocopherol concentrations correlated significantly with increased age (r = 0.35, p = 0.008). Compared to the values before start, plasma concentrations of B1 and B2 as well as ETK and/or EGR were increased significantly after finishing. The raised levels persisted 6 hours after finishing, whereas AA remained unaltered. The univariate analysis of variance revealed that the change in vitamin status after finish and 6 hours later was in part highly dependent on age, BMI and the level of physical fitness. Despite the long distance, the extensive character of the 100-km walking with its low intensity did not deteriorate the measured indicators of vitamin status.
Key words
Exercise, vitamin status, transketolase, glutathione reductase, thiamin, riboflavin, ascorbic acid, tocopherol, walking
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern
Summary
We investigated the effects of dietary docosahexaenoic acid (DHA, 22:6 n-3) and phosphatidylcholine (PC) on maze behavior and brain fatty acids in mice. Male Crj:CD-1 mice (3 wk old) were fed a diet containing 2% DHA and 3% palm oil (DHA group); 5% PC (PC group); 1% DHA, 2.5% PC and 1.5% palm oil (DHA+PC group); 5% palm oil (Palm oil control group) or MF laboratory chow (MF control group) for 7 mo. After this time maze-learning ability was assessed. The time required to reach the maze exit and the number of times that a mouse strayed into blind alleys in the maze were measured three times every four days. After the last learning test, all mice were sacrificed and plasma and brain were analyzed for fatty acid composition. The DHA and PC groups required less time to reach the maze exit and strayed less into blind alleys than the control group in the third trial. The difference between the DHA or PC groups and control mice was statistically significant (p < 0.05). In the total lipids of plasma and brain of mice fed DHA, there was a significant increase in DHA levels and a concomitant decrease in arachidonic acid (AA, 20:4 n-6). Similar changes in fatty acid composition were observed in brain phosphatidylcholine and phosphatidylethanolamine for this group of mice. However, this pattern of changes in brain fatty acids was not evident in the PC group. Our data suggest that maze-learning ability in mice is enhanced by intakes of DHA and PC. However, the mechanisms by which the DHA and PC diets improved learning ability appear to be different. A synergistic effect of DHA and PC on learning ability is not apparent in the DHA+PC group.
Key words
Docosahexaenoic acid (DHA), phosphatidylcholine (PC), maze-learning ability, brain fatty acids
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 5, © Verlag Hans Huber AG, Bern