摘要:

The purpose of this study was to examine the influence of oxidized low-density lipoprotein (oxLDL) on endothelial regrowth in an in vitro wounding model and the possible protection afforded by vitamin E (E). Endothelial cells grown on micropore filters were wounded by scraping and allowed to reestablish growth on denuded areas in the presence of LDL or oxLDL (25-200 µg/ml), linoleic acid (FA, 90 µM) or linoleic acid hydroperoxide (OFA, 15 µM) for 24 h. Some monolayers were pretreated with 25 µM E for 24 h. Transendothelial albumin movement was used as a measure of endothelial barrier function and as an indicator of endothelial monolayer regrowth. Exposure to levels of oxLDL as low as 25 µg/ml for 24 h resulted in depressed endothelial monolayer regrowth, whereas native LDL was without effect and pre-enrichment with 25 µM E offered no protection. In comparison, E preenrichment improved endothelial regrowth to control levels in FA- and OFA-treated cultures, unlike oxLDL-treated cultures. It is concluded that circulating oxLDL may reduce regrowth of wounded endothelium and supplemental E may not offer protection. Moreover, fatty acids or their hydroperoxides are unlikely to be involved in this e

ISSN:0250-6807    

DOI:10.1159/000177836

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Children living on plantations in inland districts of the southeastern part of Sri Lanka frequently develop a skin condition on the legs described as mosaic skin or xeroderma. This condition is characterized by atrophic, dry, shining and scaly skin. The etiology is unknown. A food frequency survey indicated a low energy intake, a diet with a low fat content, and anthropometric data have shown a high prevalence of malnutrition within this group. The skin condition brought attention to a possible deficiency of essential nutrients, especially essential fatty acids. In order to investigate the possible association with a deficiency of essential fatty acids, blood samples were collected from both children having signs of xeroderma and controls. The total amount of phospholipids was low, but the fatty acid profile of this lipid class was similar to the controls. A vitamin A deficiency was indicated by low levels of its transport proteins. A multifactorial etiology where vitamin A deficiency may play a role is discussed.

ISSN:0250-6807    

DOI:10.1159/000177837

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

The nutritional utilization of the lentil was compared to that of casein, used as the only protein food in young rats at two different ages: weanling and 10 days thereafter. Cooking allowed a better intake and digestive utilization of lentil crude protein by the weanling rats. In this case, methionine showed to be the first limiting factor. When lentil diets were given to the older rats, their intake and growth rates reached the level of the control rats. In this case, the free amino acid pools in the muscles were found increased in the group on cooked lentils as compared to that on raw lentils or the control group.

ISSN:0250-6807    

DOI:10.1159/000177838

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Exposing the rat fetus to maternal low-protein diets during gestation has been shown to programme a number of metabolic and physiological changes. The present study examines the effects of maternal dietary manipulation upon glutathione cycle enzymes in the rat. Pregnant rats were fed either a non-purified chow diet or purified diets containing 18, 9 or 6% casein. Enzyme activities in the resulting offspring were determined at 4 weeks of age. Weanling pups exposed to the chow diet in utero had significantly lower activities of the glutathione synthetic enzyme γ-glutamylcysteine synthetase in liver and lung than rats exposed to purified diets. Glutathione peroxidase activity in the liver also tended to be lower in these animals. Glutathione reductase activity in liver was negatively correlated with maternal protein intake, with rats exposed to 6% casein in utero having a significantly raised activity of this recycling enzyme, relative to controls exposed to 18% casein. These data are consistent with the hypothesis that components of maternal diet, including the level of protein intake, programme glutathione cycle enzymes, or production of their regulatory elements, in utero

ISSN:0250-6807    

DOI:10.1159/000177839

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Trans isomeric fatty acids disturb themetabolism of essential polyunsaturated fatty acids in animals and in premature infants. We assessed whether similar effects may also occur in healthy children. Plasma phospholipid fatty acid composition was analysed in 53 apparently healthy children aged 1-15 years (mean 7.5 years). Trans fatty acids were found in all samples and contributed 1.78 ± 0.10% (w/w, mean ± SEM). There was no relation of the major trans isomer octadecenoic acid and of total trans fatty acids to the precursor essential fatty acid linoleic acid. In contrast, we found significant inverse correlations of trans octadecenoic acid and total trans isomers to the principal n-6 metabolite arachidonic acid as well as to the sum of all n-6 metabolites. Furthermore, there was an inverse correlation of total trans fatty acids to the ratio of arachidonic to linoleic acid, an indirect indicator of linoleic acid conversion. These findings are compatible with inhibition of arachidonic acid biosynthesis by trans fatty acids. Since the availability of long-chain polyunsaturated fatty acids, including arachidonic acid, is of essential importance for tissue growth and development, these findings question the safety of high dietary trans fatty acid intakes in childhoo

ISSN:0250-6807    

DOI:10.1159/000177840

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Changes in colonic faecal microflora, enzymes of colonic energy metabolism, of cell proliferation and lipid profile in the serum and colon were studied in 48 mice exposed to cycas and fed a Nigeria-type diet. The animals were divided into three diet classes of 16 mice per class, and each class of animals was fed ad libitum either a normal diet, a high-carbohydrate high-fibre (HCF) diet or a high-protein high-fat (HPF) diet. Each diet class was subdivided into two equal groups of 8 animals each. One group was fed a diet type (acted as the diet control) without cycas, and the other group was fed the corresponding diet with cycas. The study period lasted for 3 weeks. The colonic faecal materials were acidified in the HCF-fed mice compared with the other diet-fed mice. Faecal β-glucuronidase activity was significantly (p < 0.05) increased in the cycas-fed mice compared with the diet controls. Feeding mice with the HPF diet significantly (p < 0.05) increased β-glucuronidase and mucinase activities. Colonic phosphofructokinase, glucose 6-phosphate dehydrogenase, lactate dehydrogenase and hyaluronidase activities were also significantly (p < 0.05) elevated in the cycas-treated mice. Feeding mice with the HPF diet also significantly (p < 0.05) increased these enzyme activities. Mice fed with the HCF diet significantly (p < 0.05) lowered serum total cholesterol, triglyceride and colonic total lipid. Colonic phosphatidylethanolamine and phosphatidylcholine were significantly (p < 0.05) increased in the HPF-fed mice. This study shows that the HCF diet alters the colonic faecal environment, colonic energy metabolism and hyaluronidase activity in ways which suggest its protective ability against the development of colon cancer in mic

ISSN:0250-6807    

DOI:10.1159/000177841

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

The effects of dietary supplementation with fish on plasma fatty acid levels were studied in 20 coronary heart disease patients who had suffered acute myocardial infarction. The study was divided into three periods: hospital admission, after 8 weeks on a heart-healthy diet designed for patients with ischemic heart disease, and after 4 weeks on an n-3 fatty acid-supplemented diet in which red meat was replaced with lean and fatty fish. At the end of each period, the subjects responded to a 48-hour recall questionnaire, so that we could assess their compliance with the diet, and blood samples were collected for the determination of plasma fatty acids. Stearic fatty acid was significantly decreased after the fish diet, n-7 and n-9 fatty acids showed no significant changes throughout the study. At the end of the 4-week period when the fish diet was consumed, linoleic acid and its long-chain derivative docosapentaenoic acid (22:5 n-6) were significantly increased. The most notable changes in n-3 series fatty acids at the end of the third period were the significant decrease in linolenic acid and the significant increase in its long-chain derivatives eicosapentaenoic (20:5 n-3) and docosahexaneoic acid (22:6 n-3). These changes in plasma fatty acid levels may have beneficial effects on coronary heart disease.

ISSN:0250-6807    

DOI:10.1159/000177842

出版商:S. Karger AG    

年代:1995

数据来源: Karger

摘要:

Iron plays a promoting role in lipid oxidation through several mechanisms. Therefore, hepatic iron deposits in the rat may lead to peroxidative damage and to alterations in the lipoprotein formation. In this report we observed that an iron overload in rats strongly reduced the hepatic lipoprotein secretion but did not affect oxidation resistance of native lipoproteins and erythrocyte lipids in spite of tocopherol and ascorbate deficiencies. Since oxidation resistance depends on the substrate to antioxidant vitamin molar ratio, our results show that an iron overload probably alters the lipoprotein lipid fatty acid composition in rats.

ISSN:0250-6807    

DOI:10.1159/000177843

出版商:S. Karger AG    

年代:1995

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000177844

出版商:S. Karger AG    

年代:1995

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000177845

出版商:S. Karger AG    

年代:1995

数据来源: Karger