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| Florian J. Schweigert, Andrea Hurtienne, Katharina
Bathe Improved Extraction Procedure for Carotenoids from Human Milk |
Zusammenfassung Summary |
| Florian J. Schweigert and Volker Bok Vitamin A in Blood Plasma and Urine of Dogs is Affected by the Dietary Level of Vitamin A |
Zusammenfassung Summary |
| Burim N. Ametaj, Brian J. Nonnecke, Ronald L. Horst
and Donald C. Beitz Effects of Retinoic Acid and 1,25-Dihydroxyvitamin D3 on IFN-g Secretion by Mononuclear Leukocytes from Nulliparous and Postparturient Dairy Cattle |
Zusammenfassung Summary |
| Pedro Marques-Vidal, Dominique Arveiler,
Alun Evans, Michèle Montaye, Jean Bernard Ruidavets, Bernadette Haas,
John Yarnell, Annie Bingham, Jean Ferrières, Philippe Amouyel and Pierre
Ducimetière Characteristics of Male Vitamin Supplement Users Aged 50-59 Years in France and Northern Ireland: the Prime Study |
Zusammenfassung Summary |
| Tomoko Goto, Michio Komai, Bruce P. Bryant and Yuji
Furukawa Reduction in Carbonic Anhydrase Activity in the Tongue Epithelium and Submandibular Gland in Zinc-Deficient Rats |
Zusammenfassung Summary |
| Ikuko Kato, Ann M. Dnistrian, Morton Schwartz, Paolo
Toniolo, Karen Koenig, Roy E. Shore, Anne Zeleniuch-Jacquotte, Arslan
Akhmedkhanov and Elio Riboli Risk of Iron Overload among Middle-aged Women |
Zusammenfassung Summary |
| Jacques Barnouin, Rafael Pérez Cristiá, Michelle Chassagne,
Tomás Verdura Barrios, Josiane Arnaud, Pedro Fleites Mestre, Alain Favier Vitamin and Nutritional Status in Cuban Smokers and Nonsmokers in the Context of an Emerging Epidemic Neuropathy |
Zusammenfassung Summary |
| Bernard Decarli, Claude Cavadini, Jannick
Grin, Anny Blondel-Lubrano, Françoise Narring and Pierre-André Michaud Food and Nutrient Intakes in a Group of 11 to 16 Year Old Swiss Teenagers |
Zusammenfassung Summary |
| Suzanne N. J. Geelen, Walter L. Jansen, Math J. H.
Geelen, Marianne M. Sloet van Oldruitenborgh-Oosterbaan and Anton C.
Beynen Lipid Metabolism in Equines Fed a Fat-Rich Diet |
Zusammenfassung Summary |
Zusammenfassungen / Summaries
Summary
An improved method for the extraction of the major carotenoids from human milk is described. Carotenoids were extracted from milk first with ethanol and n-hexane. Then, polar xanthophylls were extracted from n-hexane into ethanol/water. The remaining n-hexane was evaporated, the residue combined with the ethanolic milk fraction and the mixture briefly saponified. Carotenoids were extracted from the hydrolysate with n-hexane, combined with the polar xanthophylls from the non-saponified ethanol/water-extract and separated by HPLC. Using this method we were able to significantly improve the recovery of xanthophylls such as lutein and zeaxanthin from human milk. The recovery rate of all carotenoids was > 90%. This method might not only be of value for milk but should be especially useful in the extraction of carotenoids from human tissues such as the adipose tissue.
Key words
Xanthophylls, saponification, milk, human, method
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
Dogs differ from other species with respect to the occurrence of a high percentage of retinyl esters in blood plasma and the excretion of substantial amounts of vitamin A in the urine. Our investigation focussed on the effects of different concentrations of vitamin A in the diet, ranging from concentrations below NRC requirements of 25 IU/kg body weight (BW) to 2400 IU/kg BW, on the levels of retinol and retinyl esters (palmitate/oleate and stearate) in canine blood plasma and urine. The plasma levels of retinyl esters paralleled the levels of vitamin A in the feed (r = 0.91; p < 0.001). The highest plasma level (12.1 ± 0.4 mg/l) was observed at the highest level in the diet. This observation may be explained by the fact that in dogs retinyl esters are associated with lipoproteins. Even under prolonged feeding on vitamin A levels below NRC requirements, retinyl esters were still present in the plasma (2.8 ± 0.1 mg/l). Levels of retinol were not affected (1.2 ± 0.03 vs. 1.0 ± 0.03 mg/l, respectively). In the urine, the concentration of retinol and retinyl palmitate/oleate increased with the first increase of vitamin A in the diet to 1.2 ± 0.4 mg/l of total vitamin A. Urinary levels were elevated and fluctuated with up to four peaks while dietary vitamin A levels were above NRC requirements. But the amount of retinol and retinyl esters excreted did not show any dependence on the amount of vitamin A in the diet. When the amount of vitamin A in the diet was at or below requirements, only traces of retinol and retinyl esters were detected in urine. Thus, contrary to current knowledge for most other mammals, retinyl ester levels in plasma and retinol and retinyl esters in the urine of dogs proved to be clearly but differently affected by the amount of vitamin A supplied with the diet. Contrary to retinol, plasma levels of retinyl esters closely reflect the actual supply of vitamin A with the feed. The occurrence of retinol and retinyl esters in urine may, however, be due to dietary supply of vitamin A in excess of standard requirements, thereby providing a useful indicator of a dietary supply of vitamin A above requirement. The mechanism involved in the possible regulation of urinary excretion of retinol and retinyl esters remains to be elucidated.
Key words
Vitamin A, retinol, retinyl esters, plasma, urine, diet, dogs
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
Individual and combined effects of several isomers of retinoic acid (RA) and
1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on interferon-g (IFN-g) secretion
by blood mononuclear leukocytes (MNL) from nulliparous and postparturient
Holstein cattle were evaluated in vitro.
In the first experiment, effects on incubation period (24 to 72 hours) and
time of supplementation (0 to 32 hours) with all-trans, 9-cis, 13-cis-, and
9,13-dicis-RAs (0 to 100 nM) on IFN-g secretion by pokeweed mitogen (PWM)-stimulated
(0 and 10 mg/ml) MNL from nulliparous cattle were evaluated. In the second
experiment, MNL from postparturient cows (bled at 0, 2, 4, and 16 days postpartum)
were stimulated with PWM (0 and 10 mg/ml) in the presence of RA isomers (9-cis-
or 9,13-dicis-RA; 0 to 100 nM), 1,25-(OH)2D3 (0 to 100 nM), or with combinations
of these metabolites.
The results show that individual isomers of RA had no effect on IFN-g secretion
by PWM-stimulated MNL from nulliparous or postparturient cows. Furthermore
1,25-dihydroxyvitamin D3 inhibited IFN-g secretion by MNL from nulliparous
and postparturient dairy cows; however, the degree of inhibition was greater
when 9-cis- and 9,13-dicis-RA were also present in the cultures. Finally mononuclear
leukocytes from postparturient dairy cows produced substantially less IFN-g
than did MNL from nulliparous cattle.
It is concluded that retinoic acids individually did not affect the capacity
of leukocytes from dairy cattle to secrete IFN-g. This result is in marked
contrast to studies in monogastric species indicating that RAs inhibit IFN-g
secretion by peripheral blood T cells. Inhibition of IFN-g secretion by 1,25-(OH)2D3
was potentiated by 9-cis- and 9,13-di-cis-retinoics acids, suggesting that
an excess of dietary vitamins A and D may compromise further the naturally
immunosuppressed postparturient dairy cow. Additional research is necessary
to determine if the combined effects of these metabolites on IFN-g secretion
represent an increased susceptibility of the dairy cow to infectious diseases
during the periparturient period. Lower secretion of IFN-g by MNL from postpartutient
dairy cows, relative to nulliparous cattle, suggests that recently-calved
cows are naturally immunosuppressed.
Key words
Interferon-g, retinoic acid, 1,25-dihydroxyvitamin D3, postparturient cow
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
The prevalence and characteristics of vitamin supplement users were assessed
in 7538 male subjects aged 50-59 from France and 2468 from Northern Ireland.
In France, 15% of subjects used vitamin supplements; users were significantly
younger, had a lower body mass index, a higher educational level, had more
frequently a hard physical job, reported more frequently a personal history
of disease and were less frequently retired or inactive than non-users. In
Northern Ireland, 21% of subjects were vitamin supplement users; users had
a lower body mass index, drank less alcohol, had a higher educational level,
were more frequently non-smokers and professionally active, and reported a
hard physical job and the practice of leisure sports more frequently than
non-users. Finally, vitamin supplement users in Northern Ireland had a lower
consumption of alcohol, smoked less, had a lower frequency of personal history
of disease and were more frequently on dietary therapy for hypertension or
dyslipidaemia than their French counterparts.
We conclude that vitamin supplement use is associated with a healthier lifestyle
and with dietary measures against hypertension and dyslipidaemia in Northern
Ireland. The less favorable lifestyle observed for vitamin supplement users
in France awaits further investigation.
Key words
vitamin supplements, epidemiology, socioeconomic status, prevention, hypertension, dyslipidaemia
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3, © Verlag Hans Huber AG, Bern
Summary
We investigated the effects of zinc deficiency on carbonic anhydrase (CA) activity in the tongue epithelium and submandibular gland in rats. Male 4-week-old SD rats were given free access to a diet containing 2.2 (zinc-deficient), 4.1 (low-zinc), or 33.7 (zinc-sufficient) mg zinc/kg diet for 6 weeks. Rats in the fourth group (receiving 33.7 mg zinc/kg) were pair-fed against the zinc-deficient rats. Biochemical analysis at the end of the experimental period indicated that zinc deficiency significantly reduced CA activity in the tongue epithelium and submandibular gland, and the CA activity levels in these tissues seemed to parallel the dietary zinc levels. By enzyme histochemistry, an intensely positive reaction for CA was observed in the middle and basal regions of the taste buds in the circumvallate papilla in the zinc-sufficient and pair-fed (control) rats. The cells in von Ebner's glands also showed a strong positive reaction in control rats, although only a weak reaction product was found in zinc-deficient rats. These results suggest that CA activity is affected by the dietary content of zinc, which is considered to be an indispensable factor for the maintenance of normal taste sensation.
Key words
Zinc deficiency, carbonic anhydrase, rat, taste cells, submandibular glands
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
Iron overload, expressed as increased body iron stores, has been recognized as a potential hazard because it promotes the generation of oxygen radicals. We analyzed factors associated with serum ferritin levels (an indicator of body iron stores) among middle-aged women with a high prevalence of nutrient supplement use. Serum ferritin concentrations were determined on automated immunoassay for 487 healthy women with the mean age of 57 years who participated in the New York University Women's Health Study. The mean serum ferritin concentration in postmenopausal women was more than twice that in premenopausal women. Serum ferritin concentrations progressively increased with advancing age, but adjustment for menopausal status considerably weakened this association. Among non-dietary factors, nonwhite ethnicity, obesity and cigarette smoking were positively associated with serum ferritin concentrations. After adjustment for these factors and for menopausal status, serum ferritin levels were positively associated with meat intake and multivitamin use and inversely associated with breakfast cereal consumption. However, none of these lifestyle factors positively associated with serum ferritin levels had a significant impact on serum ferritin levels above 100 ng/ml (. median concentration). Our results suggest that iron overload seems unlikely among middle aged women through their diet and nutritional supplements.
Key words
Iron, diet, supplements, women
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
A prospective survey was conducted in a random sample of smokers (SMO) and non-smokers (NON) men living in Havana. The aim of the survey was to investigate metabolic and dietary parameters discriminating between SMO and NON volunteers, which could explain underlying mechanisms to the higher risk of Epidemic Neuropathy (51000 reported cases in Cuba from late 1991) previously demonstrated in the Cuban smoker. Forty three blood markers were determined and dietary intakes evaluated during 4 seasonal periods. a-carotene, b-carotene, b-cryptoxanthin, total carotenoids and riboflavin blood concentrations were lower in SMO vs. NON subjects. Activities of glutathione reductase and butryrylcholinesterase were lower in the SMO group, as did total protein levels. Copper and thiocyanates were higher in SMO subjects. Most of the dietary parameters did not differ between the two groups of volunteers. Low biologically available quantities of carotenoids and riboflavin from low dietary intakes and depletion through smoking would be the main precipitating factors of Epidemic Neuropathy. Protein depletion and copper delivery via tobacco smoke, sunlight exposure, level of physical activity and high consumption of cigarettes, in a context of low dietary supplies concerning especially B vitamins, were probably aggravating factors through oxidative stress and impairment of cyanide detoxification.
Key words
Smoking, carotenoid, riboflavin, protein, copper, light, epidemiology, eye, epidemic neuropathy, Cuba
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
Better knowledge of the dietary intake of teenagers is necessary to help health professionals to provide better advice on an individual and data for prevention and health programme. We carried out a dietary survey by 3-day records technique in a group of adolescents living in the Canton of Vaud, Switzerland. Food habits were traditional but rich in refined products and poor in plant food. Mean daily energy intake, which was 8025 kJ for the girls and 9350 kJ for boys, was lower than the recommended dietary allowances, especially for girls. Independently of the gender, breakfast represented 19% of the total daily energy intake, lunch 31% and dinner 29%. Total energy provided by snacks was 23.0% for girls and 20.4% for boys. The percentage of energy supplied by the afternoon snack was 15.8% for the girls and 13.3% for the boys. The source of energy was 14% from protein, 37% from fat and 49% from carbohydrates. A high percentage of adolescents had low micronutrient intakes (vitamins A, E, B1, B6, C, folates and for minerals magnesium, calcium and iron). An increase intake of vegetables and fruit should thus be strongly encouraged; snacking could offer a target vector to improve dietary nutritional quality.
Key words
Adolescent, 3-day record, food, micronutrients intake, survey, energy intake, nutrition
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern
Summary
The hypothesis tested was that dietary fat, when compared with an isoenergetic amount of non-structural carbohydrates, stimulates lipolysis in adipose tissue and also stimulates the fatty-acid oxidative capacity in skeletal muscle from horses. Six adult horses were fed a high-fat, glucose or starch containing diet according to a 3 ´ 3 Latin square design with feeding periods of three weeks. The diets were formulated so that the intake of soybean oil versus either glucose or corn starch were the only variables. In accordance with previous work, whole plasma triacylglycerol (TAG) concentration decreased significantly by 58% following fat supplementation. This fat effect was accompanied by a 247% increase in lipoprotein lipase (LPL) activity in post-heparin plasma. The dietary variables did neither significantly affect the basal in vitro lipolytic rate nor the lipolytic rate after adding noradrenaline. There was no significant diet effect on the activities of hexokinase and phosphofructokinase as indicators of glycolytic flux and citrate synthase and 3-hydroxy-acyl-CoA dehydrogenase as indicators of fatty-acid oxidative capacity. The concentrations of muscle glycogen and TAG were not affected by fat supplementation. It is concluded that our hypothesis is not supported by the present results.
Key words
Horse, dietary fat, lipoprotein lipase, adipose lipolysis, glycolytic flux, fatty acid oxidation
International Journal for Vitamin and Nutrition Research,
Band 70, 2000, Heft 3 © Verlag Hans Huber AG, Bern