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The aim of the study was to investigate whether a supplement of antioxidants to subjects with a high working pace can influence the antioxidant capacity. The study was parallel and double blind with 98 subjects randomised into two groups. One of the groups was given a test drink with antioxidants for 4 weeks (450 ml/day) while the other group took a corresponding amount of placebo drink. The test drink contained: 2 mg beta-carotene/100 ml, 40 mg alphatocopherol/100 ml, 80 mg ascorbic acid/100 ml, 2 mg pyridoxine/100 ml, 15 mg magnesium/100 ml, 0.2 mg manganese/100 ml, 1 mg zinc/100 ml, 0.1 mg copper/100 ml and 10 [micro]g selenium/100 ml. Consumption of the test drink for 4 weeks increased the total plasma antioxidant capacity by 7% (ferric reducing ability of plasma method, P < 0.05 compared with the placebo group), and the content of selenium and selenoprotein P in serum was raised by 16-17% (P < 0.001 compared with the placebo group). No significant changes were found in the placebo group. The test drink also contained Lactobacillus plantarum 299v (5 x [10.sup.7] cfu/ml) and 4 weeks consumption led to a significant increase of Lb. plantarum 299v in the faeces. In conclusion, consumption of a drink rich in different antioxidants can increase the antioxidant capacity in subjects with a high working pace. This can be valuable since it may increase the protection against reactive oxygen radicals.

A study was done to determine the extent of variation in dietary fiber and beta-glucan content of oats grown in Sweden and to investigate their correlation with kernel size and protein, fat and starch content. Beta-glucan content was found to be positively correlated with insoluble dietary fiber, total dietary fiber and fat content, but was negatively correlated with starch content.

Objectives: To investigate side by side the effects on serum lipoproteins and postprandial glucose and insulin concentrations of beverages enriched with 5 or 10 g of [beta]-glucans from oats or barley. Design and setting: An 8-week single blind, controlled study with five parallel groups carried out at two centres under identical conditions. Subjects: A total of 100 free-living hypercholesterolaemic subjects were recruited locally and 89 completed the study. Interventions: During a 3-week run-in period all subjects consumed a control beverage. For the following 5-week period four groups received a beverage with 5 or 10 g [beta]-glucans from oats or barley and one group continued with the control beverage. Blood samples in weeks 0, 2, 3, 7 and 8 were analysed for serum lipids, lipoproteins, glucose and insulin. Postprandial concentrations of glucose and insulin were compared between control and the beverage with 5 g of [beta]-glucans from oats or barley. Results: Compared to control, 5 g of [beta]-glucans from oats significantly lowered total-cholesterol by 7.4% (P [less than] 0.01), and postprandial concentrations of glucose (30 min, P=0.005) and insulin (30 min, P=0.025). The beverage with 10 g of [beta]-glucans from oats did not affect serum lipids significantly in comparison with control. No statistically significant effects compared to control of the beverages with barley [beta]-glucans were found. Conclusions: A daily consumption of 5 g of oat [beta]-glucans in a beverage improved the lipid and glucose metabolism, while barley [beta]-glucans did not. Sponsorship: Founded by the European Commission (QLK1-CT-2000-00535). European Journal of Clinical Nutrition (2005) 59, 1272-1281. doi: 10.1038/sj.ejcn.1602240; published online 13 July 2005 Keywords: [beta]-glucan, oats, barley, LDL-cholesterol, glucose, insulin, Author(s): M Biorklund [1]; A van Rees [2]; R P Mensink [2]; G Onning [1] Introduction As early as 1963 de Groot and co-workers observed that oats lowered serum total-cholesterol [...]

Background: Different healthy food patterns may modify cardiometabolic risk. We investigated the effects of an isocaloric healthy Nordic diet on insulin sensitivity, lipid profile, blood pressure and inflammatory markers in people with metabolic syndrome.Methods: We conducted a randomized dietary study lasting for 18-24 weeks in individuals with features of metabolic syndrome (mean age 55 years, BMI 31.6 kg m(-2) , 67% women). Altogether 309 individuals were screened, 200 started the intervention after 4-week run-in period, and 96 (proportion of dropouts 7.9%) and 70 individuals (dropouts 27%) completed the study, in the Healthy diet and Control diet groups, respectively. Healthy diet included whole-grain products, berries, fruits and vegetables, rapeseed oil, three fish meals per week and low-fat dairy products. An average Nordic diet served as a Control diet. Compliance was monitored by repeated 4-day food diaries and fatty acid composition of serum phospholipids.Results: Body weight remained stable, and no significant changes were observed in insulin sensitivity or blood pressure. Significant changes between the groups were found in non-HDL cholesterol (-0.18, mmol L(-1) 95% CI -0.35; -0.01, P = 0.04), LDL to HDL cholesterol (-0.15, -0.28; -0.00, P = 0.046) and apolipoprotein B to apolipoprotein A1 ratios (-0.04, -0.07; -0.00, P = 0.025) favouring the Healthy diet. IL-1 Ra increased during the Control diet (difference -84, -133; -37 ng L(-1) , P = 0.00053). Intakes of saturated fats (E%, beta estimate 4.28, 0.02; 8.53, P = 0.049) and magnesium (mg, -0.23, -0.41; -0.05, P = 0.012) were associated with IL-1 Ra.Conclusions: Healthy Nordic diet improved lipid profile and had a beneficial effect on low-grade inflammation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to investigate how a diet high in dietary fiber, with several fiber sources included, modulates glucose and lipid metabolism and the inflammatory response in humans., Methods: Subjects (n = 25) aged 58.6 (1.1) years (mean and SD) with a BMI of 26.6 (0.5) kg/m(2) and a total cholesterol (TC) of 5.8 (0.1) mmol/L (mean and SEM) were given a high fiber (HF) and low fiber (LF) diet, in a randomized controlled 5-week crossover intervention, separated by a 3-week washout. The HF diet consisted of oat bran, rye bran, and sugar beet fiber incorporated into test food products; one bread roll, one ready meal, and two beverages consumed daily. Equivalent food products, without added fibers, were provided in the LF diet., Results: Total dietary fiber intake was 48.0 g and 30.2 g per day for the HF and LF diet, respectively. Significant reduction in C-reactive protein (CRP) was observed between the diets (P = 0.017) and a significant reduction in fibrinogen within the HF diet (P = 0.044). There were no significant effects in other measured circulating cytokines or in glucose, insulin, and lipid levels., Conclusions: Our study suggests that a 5-week high dietary fiber intake of oat bran, rye bran, and sugar beet fiber might reduce the low-grade inflammatory response measured as CRP which could, together with reduced fibrinogen, help to prevent the risk of cardiovascular disease.

The objective was to investigate the alterations of plasma metabolome profiles to identify exposure and effect markers of dietary fiber intake. Subjects (n = 25) aged 58.6 (1.1) years (mean and SD) with a body mass index of 26.6 (0.5) kg/m(2) were given a high fiber (HF) and a low fiber (LF) diet, in a 5-week randomized controlled crossover intervention. The HF diet consisted of oat bran, rye bran, and sugar beet fiber incorporated into test food products, whereas the LF diet was made of equivalent food products to the HF diet, but without adding fibers. Blood plasma samples were collected at the start and end of each intervention period and analyzed by LC-QTOF/MS. In total, 6 features in positive mode and 14 features in negative mode were significantly different between the HF and the LF diet (p < 0.01, q < 0.05). Two markers, 2,6-dihydroxybenzoic acid and 2-aminophenol sulfate, were increased after HF diet, along with a tentatively identified saponin derived from oat avenacosides. The untargeted metabolomics approach enabled the identification of two new markers of dietary fiber intake in human plasma. Further studies will be needed to verify if these markers could serve as compliance markers of fiber intake.

The present review examines the evidence regarding the effect of β-glucan on variables linked to the metabolic syndrome (MetS), including appetite control, glucose control, hypertension, and gut microbiota composition. Appetite control can indirectly influence MetS by inducing a decreased energy intake, and promising results for a β-glucan intake to decrease appetite have been found using gut hormone responses and subjective appetite indicators. Beta-glucan also improves the glycemic index of meals and beneficially influences glucose metabolism in patients with type 2 diabetes or MetS, as well as in healthy subjects. Furthermore, a blood-pressure-lowering effect of β-glucan in hypertensive subjects seems fairly well substantiated. The gut microbiota composition might be an interesting target to prevent MetS, and preliminary results indicate the prebiotic potential of β-glucan. The evidence that β-glucan influences appetite control and gut microbiota in a positive way is still insufficient or difficult to interpret, and additional studies are needed in this field. Still, much evidence indicates that increased β-glucan intake could prevent MetS. Such evidence should encourage increased efforts toward the development of β-glucan-containing functional foods and promote the intake of β-glucan-rich foods, with the aim of reducing healthcare costs and disease prevalence., (© 2012 International Life Sciences Institute.)

The understanding of how fibre-rich meals regulate molecular events at a gene level is limited. This pilot study aimed to investigate changes in gene expression in peripheral blood mononuclear cells (PBMCs) from healthy subjects after consumption of an oat bran-rich meal. Fifteen subjects (8 men and 7 women, aged 20-28 years) ingested meals with oat bran or a control meal after an overnight fast. Blood samples for analysis of postprandial glucose, insulin and triglyceride concentrations were taken during 3 h, while PBMCs for microarray gene expression profiling from five men and five women were taken before and 2 h after the meal. Analysis of transcriptome data was performed with linear mixed models to determine differentially expressed genes in response either to meal intake or meal content, and enrichment analysis was used to identify functional gene sets responding to meal intake and specifically to oat bran intake. Meal intake as such affected gene expression for genes mainly involved in metabolic stress; indicating increased inflammation due to the switch from fasting to fed state. The oat bran meal affected gene sets associated with a lower insulin level, compared with the control meal. The gene sets included genes involved in insulin secretion and β-cell development, but also protein synthesis and genes related to cancer diseases. The oat bran meal also significantly lowered postprandial blood insulin IAUC compared to control. Further studies are needed to compare these acute effects with the long-term health effects of oat bran.

Epidemiological and animal studies have shown that dietary fiber is protective against the development of colon cancer. Dietary fiber is a rich source of the hydroxycinnamic acids ferulic acid (FA) and p-coumaric acid (p-CA), which both may contribute to the protective effect. We have investigated the effects of FA and p-CA treatment on global gene expression in Caco-2 colon cancer cells. The Caco-2 cells were treated with 150 μM FA or p-CA for 24 h, and gene expression was analyzed with cDNA microarray technique. A total of 517 genes were significantly affected by FA and 901 by p-CA. As we previously have found that FA or p-CA treatment delayed cell cycle progression, we focused on genes involved in proliferation and cell cycle regulation. The expressions of a number of genes involved in centrosome assembly, such as RABGAP1 and CEP2, were upregulated by FA treatment as well as the gene for the S phase checkpoint protein SMC1L1. p-CA treatment upregulated CDKN1A expression and downregulated CCNA2, CCNB1, MYC, and ODC1. Some proteins corresponding to the affected genes were also studied. Taken together, the changes found can partly explain the effects of FA or p-CA treatment on cell cycle progression, specifically in the S phase by FA and G(2)/M phase by p-CA treatment.

Today, the gut microbiota is considered a key organ in host nutritional metabolism and recent data have suggested that alterations in gut microbiota contribute to the development of type 2 diabetes and obesity. Accordingly, a whole range of beneficial effects relating to inflammation and gut health have been observed following administration of probiotics to both humans and different animal models. The objective of this study was to evaluate the metabolic effects of an oral probiotic supplement, Lactobacillus plantarum DSM 15313, to high-fat diet (HFD) fed C57BL/6J mice, a model of human obesity and early diabetes. The mice were fed the experimental diets for 20 weeks, after which the HFD had induced an insulin-resistant state in both groups compared to the start of the study. The increase in body weight during the HFD feeding was higher in the probiotic group than in the control group, however, there were no significant differences in body fat content. Fasting plasma glucose levels were lower in the group fed the probiotic supplement, whereas insulin and lipids were not different. Caecal levels of short-chain fatty acids were not significantly different between the groups. An oral glucose tolerance test showed that the group fed probiotics had a significantly lower insulin release compared to the control group, although the rate of glucose clearance was not different. Taken together, these data indicate that L. plantarum DSM 15313 has anti-diabetic properties when fed together with an HFD.

Type 2 diabetes is associated with a higher cardiovascular risk and there has been a growing interest in using dietary intervention to improve lipid profile and glucose control. The present work aims at analysing the effects of the enrichment of a normal diet with beta-glucan (3.5 g/d) in free-living type 2 diabetic subjects for 2 months, using a palatable soup. This trial was a parallel, placebo-controlled, double-blinded randomised study performed in fifty-three type 2 diabetic subjects. During a 3-week run-in period, subjects daily consumed a ready meal control soup (without beta-glucan). For the following 8 weeks, subjects were randomly assigned to consume daily either a control soup or a beta-glucan soup. Changes in lipid profile (total cholesterol (TC), HDL- and LDL-cholesterol (HDLc and LDLc), apo B and TAG) and in glucose control (HbA1c and fasting glucose) were measured. There was no significant alteration in lipid profile in the two groups (TC, HDLc, LDLc and apo B). TAG decreased significantly in the beta-glucan group compared with the control group ( - 0.12 (SD 0.38) v. 0.12 (SD 0.44) mmol/l, P = 0.03). HbA1c and fasting glucose were not reduced in any group. A single daily ingestion of 3.5 g beta-glucan, as required by official dietary recommendations, for 8 weeks did not change the lipid profile and HbA1c in type 2 diabetic subjects. To improve the metabolic profile of type 2 diabetic subjects in the long term, the quantity, the food vectors and the tolerability of beta-glucan products may be re-evaluated.

Objective: To analyze vitamin D concentration and its association with body composition of children in Huairou district of Beijing, to provide evidence for evaluation and improvement of nutritional status of vitamin D in children., Methods: Totally, 381 children aged 7 - 11 years were recruited in Huairou district of Beijing (40.3 degrees N). Samples of overnight fasting venous blood (drawn between 0630 and 0900) were obtained in late March. Serum 25-hydroxyvitamin D [25(OH)D]concentration was determined by ELISA kits (IDS Ltd, UK). Body composition indices of the whole body, the distal and proximal forearm were measured using dual-energy X-ray absorptiometry (DEXA, Norland, USA)., Results: The average serum 25(OH)D concentration of all subjects was (44.4 +/- 12.5) nmol/L. The percentage of vitamin D insufficient [serum 25(OH)D < / = 50 nmol/L] reached as high as 68.5% (261 people). The 25(OH)D concentration of boys (46.3 nmol/L +/- 13.3 nmol/L)was significantly higher than that of girls (42.0 nmol/L +/- 11.1 nmol/L), (t = 3.38, P < 0.01). Between the serum 25(OH)D concentration and lean body mass of proximal forearm, distal forearm, whole body, and four limbs, significant positive correlations (r = 0.13 - 0.19, P < 0.05)were observed. After age, gender, height and weight were under controlled for, correlations between the serum 25(OH)D concentration and lean body mass at proximal forearm, and the two lower limbs still existed (r = 0.12-0.14, P < 0.05). The serum 25(OH)D concentration, the percentage of body fat at proximal forearm, and distal forearm were negatively correlated (r = -0.14, P < 0.05; r = -0.11, P < 0.05). However, after adjusting for confounding effects, this correlation disappeared. No significant correlation between the serum 25(OH)D concentration and body fat was observed at any position., Conclusion: Vitamin D deficiency was common in children of suburb area of Beijing. Vitamin D status was positively associated with the lean body mass.

Background: Consumption of soluble dietary fibre is correlated with decreased postprandial glucose and insulin responses and hence has beneficial effects on the metabolic syndrome., Aim of the Study: To investigate the effects on postprandial glucose, insulin and triglyceride concentrations of meals enriched with soluble dietary fibres from oats, rye bran, sugar beet fibre or a mixture of these three fibres., Methods: Thirteen healthy human volunteers (6 men and 7 women, aged 20-28 years) were included in the study. The subjects came to the study centre once a week after an overnight fast to ingest test meals and a control meal in random order. The meals contained either oat powder (62 g, of which 2.7 soluble fibre), rye bran (31 g, of which 1.7 g soluble fibre), sugar beet fibre (19 g, of which 5 g soluble fibre), a mixture of these three fibres (74 g, of which 1.7 g soluble fibre from each source, giving 5 g soluble fibre) or no added fibre (control) and were all adjusted to contain the same total amount of available carbohydrates. Blood samples were drawn before and every 30 min up to 180 min after the meals., Results: Meals with rye bran gave a lower postprandial glucose peak when compared with the control meal, and this effect was more pronounced in women compared to men. Oat powder, containing a low amount of total fibre and a high amount of carbohydrates in liquid matrix, gave a higher incremental glucose peak concentration compared to rye bran and sugar beet fibre and higher insulin incremental area under curve compared to control. The oat powder also influenced the effects of the mixed meal, diminishing the glucose-lowering effects. Postprandial triglyceride levels tended to be higher after all fibre-rich meals, but only significant for oat powder and the mixed meal when compared with the control meal., Conclusions: Postprandial glucose, insulin and triglyceride concentrations are influenced by dietary fibre-rich meals, depending on fibre source, dose of soluble and total fibre and possibly gender.

Background/aims: To investigate whether a daily intake of a nutrient-balanced ready meal containing 4 g of oat beta-glucans lowers total cholesterol (T-C) and low-density-lipoprotein cholesterol (LDL-C) in hyperlipidemic subjects and to evaluate its effect on postprandial glucose and insulin concentrations., Methods: A parallel, placebo-controlled trial was carried out in 43 healthy men and women with elevated serum cholesterol levels. During the 3-week run-in period, all subjects consumed daily a ready-meal soup, low in energy and fat and high in fiber but without oat beta-glucans. Subjects were then randomly assigned for the following 5-week intervention period to either continue consumption of the control soup or an equal soup supplemented with beta-glucan., Results: Consumption of the beta-glucan-enriched ready meal decreased T-C (0.22 +/- 0.41 mmol/l) and LDL-C (0.16 +/- 0.36 mmol/l), but the reductions were not significantly lower compared with control. After a meal with beta-glucan soup, neither postprandial glucose nor insulin concentrations were significantly different from those after a control soup., Conclusion: A daily dose of 4 g of oat beta-glucans incorporated into a healthy ready meal did not significantly lower T-C and LDL-C compared with an equal ready meal without beta-glucans. Thus, if a food product fulfils general healthy dietary recommendations it may not necessarily be a candidate for supplementation with beta-glucans., (2008 S. Karger AG, Basel.)

The biosynthesis of selenoproteins was studied in relation to milk formation and mammary cell biology by incubating the bovine mammary cell line MAC-T with ((75)Se)selenite. Intracellular proteins and proteins secreted into the cell culture medium were separated by 2D electrophoresis, the selenoproteins were detected by autoradiography, and the proteins were identified by MALDI-TOF. Approximately 35 (75)Se-containing spots were found in the cell proteins from MAC-T cells. Among them, one-third showed high intensity. The strongest spot was identified as glutathione peroxidase 1. About 20 spots were observed in protein precipitated from cell culture medium, one-third of them being distinctly visible. In an attempt to study a perturbation of the system, the effect of retinoic acid (RA) on the formation of selenoproteins was investigated. The concentration of (75)Se in total cell protein was reduced by about 35% in cells cultured with RA compared with control cells, while the opposite effect was observed in protein precipitated from cell culture medium, which contained 60% more (75)Se in RA-treated samples than in controls. There were also indications that RA might affect different selenoproteins in different ways. The methods described provide a promising approach for further studies of the regulation of selenoprotein formation in the mammary gland.

To study the role of trace elements for the quality and nutritional value of bovine milk, the distribution of selenium, zinc, and copper in whey was investigated using a method linking size exclusion chromatography to inductively coupled plasma mass spectrometry (SEC-ICP-MS). Three major peaks were detected for selenium, two peaks for zinc, and five peaks for copper. More than 65% of the selenium was found in protein fractions, mainly in fractions coinciding with the major whey proteins beta-lactoglobulin and alpha-lactalbumin. All zinc was associated with low molecular weight compounds (<5 kDa) and one of these compounds was probably citrate. More than 60% of the copper eluted in protein fractions and two of the five major peaks probably contained metallothionein and citrate. This method was used to compare milk and whey produced by organic and conventional feeding procedures. The selenium content in whey and desalted milk produced using organic regimens was significantly lower than that in conventional samples. Moreover, the proportion of selenium in protein fractions of organic whey was significantly smaller than that in conventional whey, but the distributions of zinc and copper did not differ. This study showed that with the SEC-ICP-MS technique the distribution profiles of several trace elements in whey could be studied in the same run and that the selenium profile differed in whey produced by organic and conventional procedures.

Background: Iron deficiency in children is a major worldwide nutritional problem. An oat beverage was developed for 1- to 3-year-old children and different treatments were used to improve the iron bioavailability., Aim of the Study: To investigate the effects of citric acid addition, phytase treatment and supplementation with different iron compounds on non-heme iron absorption in human from a mineral-supplemented oat-based beverage., Methods: A 240 g portion of a 55Fe-labeled test product (T) or a 59Fe-labeled reference dose (R) was served as breakfast after overnight fasting on four consecutive days in the order of TRRT. On day 18 the retention of 59Fe was measured by a whole-body counter and the erythrocytes uptake of 55Fe and 59Fe by a liquid-scintillation counter. Forty-two healthy subjects (men and women) were randomized into four study groups, members of each being given one of the studied four products (A, B, C, and D) supplemented with Fe (1.3 mg/portion), Zn, Ca, Se and P. Ferric ammonium citrate (FeAC) was added to products A, B, and C and ferric pyrophosphate (FePP) to product D. Citric acid (60 mg/portion) was added to products B, C, and D and phytase treatment applied to products C and D., Results: Citric acid improved iron absorption by 54% from 3.9% in product A to 6.0% in product B (p = 0.051). Phytase treatment increased iron absorption by 78% (from 6.0 to 10.7%, p = 0.003) by reducing the phytate-phosphorus content per portion from 16.3 mg in product B to 2.8 mg in product C. The two compounds gave similar iron absorption rates (p = 0.916)., Conclusions: A combination of citric acid addition, dephytinization and iron supplementation significantly increased the iron absorption in an oat-based beverage. Such a beverage can be useful in the prevention of iron deficiency in 1- to 3-year-old children.

To elucidate the possible role of selenoproteins for milk formation and mammary gland physiology, the activities of selenoprotein enzymes and the expression of selenoprotein genes were studied in the bovine mammary gland. Messenger RNA was demonstrated for selenoprotein P, thioredoxin reductase 1, and for glutathione peroxidase (GPx) 1, 3, and 4. Significant differences in mRNA expression between the cows were seen for GPx 1 and GPx 3. The enzyme activity of glutathione peroxidase varied approximately 16-fold among cows, and the activity of thioredoxin reductase and the concentration of soluble Se varied approximately 6-fold among cows. There were positive correlations between glutathione peroxidase activity, thioredoxin reductase activity, and soluble Se, the correlation between glutathione peroxidase activity and soluble Se being the strongest. Furthermore, selenoprotein P expression correlated with GPx 1 mRNA expression and with soluble Se. There was also a correlation between glutathione peroxidase activity and the mRNA expression of GPx 1. The general conclusion from the data was that the activity of glutathione peroxidase and thioredoxin reductase and the mRNA expression of selenoprotein P and GPx 1 and 3 were influenced by Se status, but the expression of GPx 4 and thioredoxin reductase 1 were not. These results indicate that the Se status in mammary tissue is an important regulator of selenoprotein activity and expression, but that other factors are also in operation.

Yeast, fungal, and dietary beta-glucans have immune-modulating effects in vitro and in vivo, as thought, mainly by affecting leukocytes; however, effects of oat beta-glucan on enterocytes have never been studied. As recognized, supplying oat beta-glucans as such to cells in culture directly is difficult because of solubility problems. Therefore, six ileostomic patients consumed, in random order, a control diet or an oat beta-glucan enriched diet (5 g) and from the collected ileostomic content, fecal water was prepared and added to two small intestinal cell lines (INT407, Caco-2) and two colon cell lines (HT29, T84) together with a cytokine cocktail (IL-1beta + INFgamma + TNFalpha). Several parameters reflecting immune-modulation were measured. As compared to placebo fecal water, beta-glucan enriched fecal water significantly increased IL-8 production in HT29 (5.0%; p = 0.046) and INT407 cells (22.0%; p = 0.028). Intercellular adhesion molecule (ICAM)-1 expression increased in T84 (11.0%; p = 0.028) and Caco-2 cells (20.4%; p = 0.075). These immune-stimulating effects were confirmed by enhancement of inflammatory expression profiles, as determined with an antibody array. Our findings show immune enhancement by fecal water from ileostomic patients consuming oat beta-glucan both in small intestinal and colon cell lines after stimulation, which is in agreement with documented effects in leukocytes. Whether these immune-stimulating effects on enterocytes contribute to the enhanced protection of the host against invading pathogens as observed both in animals and in humans, as well as the underlying mechanism, needs further evaluation.

Background: beta-Glucan can reduce serum concentrations of total and LDL cholesterol. The mechanism of this action is not clear, however, and it is difficult to predict the cholesterol-lowering effect of a food product enriched with beta-glucan., Objectives: We examined the effects of a beta-glucan-enriched fruit juice on serum lipids and lipoproteins and on markers of cholesterol absorption (serum concentrations of plant sterols) and synthesis (serum concentrations of lathosterol). In addition, we measured effects on lipid-soluble antioxidants., Design: After a 3-wk run-in period, healthy subjects consumed daily a fruit drink providing 5 g rice starch [placebo (control) group; n = 22] or beta-glucan from oats (n = 25) for 5 wk (parallel design). At the end of the run-in period and at the end of the intervention, blood samples were taken for analysis of lipids and lipoproteins, noncholesterol sterols, and fat-soluble antioxidants. Changes between the end of the run-in period and the end of the intervention were calculated for each subject. Differences in changes between the groups were analyzed statistically., Results: The differences between the control and beta-glucan groups in the change in serum concentrations of total and LDL cholesterol, respectively, were -4.8% (P = 0.012) and -7.7% (P = 0.005). The differences between the groups in the change in serum concentrations of lathosterol and sitosterol were -13% (P = 0.023) and -11% (P = 0.030), respectively. No significant effects were found on fat-soluble antioxidants., Conclusions: Beta-glucan lowers serum concentrations of total and LDL cholesterol when incorporated into a fruit drink. A reduced cholesterol absorption contributes to the cholesterol-lowering effect of beta-glucan without affecting plasma concentrations of lipid-soluble antioxidants.

Ferulic acid (FA) and para-coumaric acid (p-CA) may mediate the protective effects of whole-grain cereals against colon cancer. Therefore, the effects of FA and p-CA on the metabolic activity, proliferation, cell cycle phase distribution, and kinetics of the colonic endothelial tumor cell line Caco-2 was studied. Both compounds at 1500 microM decreased the number of cells to 43-75% of control after 2-3 days of treatment. Cell cycle phase distribution and cell cycle kinetics were determined by flow cytometric analysis after bromodeoxyuridine labeling. Each compound at 1500 microM decreased the proportion of cells in the G(1) phase and increased the proportion of cells in the S and G(2) phases. Treatment with 1500 microM FA significantly increased the length of the S phase, while p-CA did not. It was concluded that FA and p-CA inhibited cell proliferation by presumably affecting different cell cycle phases, and this warrants further investigations because this inhibition may be one explanation for the diet-related protection against cancer.

A comparison was made on the use of two spectrophotometric methods, the ferric reducing antioxidant power (FRAP) method and the 2,2'-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) method, for the measurement of the total antioxidant capacity (TAC) of plant foods. The correlations of TAC measured by the two methods were highly significant in both water-soluble (r2= 0.90) and water-insoluble extracts (r2= 0.98) from 13 strawberry samples. Also a corresponding comparison of TAC in extracts from 14 plant species showed high correlation coefficients, r2= 0.98 for water-soluble extracts and r2= 0.88 for water-insoluble extracts. The ratio of TAC values obtained with the two methods (ABTS/FRAP) varied between 0.7 and 3.3 for different plant extracts indicating that they contained antioxidants with varying reactivity in the two methods. TACs in six pure antioxidant substances were ranked in the following order by both methods: quercetin > ferulic acid > catechin > rutin > caffeic acid > Trolox = chlorogenic acid. The two methods showed similar TAC values for quercetin, rutin, caffeic acid and chlorogenic acid while ferulic acid and catechin gave higher results with the ABTS method than with the FRAP method, and such differences probably explain the varying ratios of ABTS/FRAP obtained in foods. Regarding storage TAC in water-soluble strawberry extracts stored at -20 or -80 degrees C was stable for at least five months while storage at 4 degrees C decreased the TAC value with 40% during five weeks of storage. The study showed that both the ABTS and FRAP methods can be used for convenient monitoring of the antioxidant capacities in fruit and vegetables, and that different antioxidants had varying reactivity in the two methods.

Fish accumulate significant amounts of selenium and are an important dietary source of this element. Some studies have however indicated a low bioavailability of the selenium from fish. Since little is known of the selenium forms in fish, we have studied soluble selenium compounds in fish species, and compared different techniques for fractionation of selenocompounds (size-exclusion chromatography, ultrafiltration, and precipitation with trichloroacetic acid). The size-exclusion column (Superdex 200 HR 10/30) was coupled on-line to inductively coupled plasma mass spectrometry (ICP-MS). The limit of detection was 0.20 microgram l-1 and the selenium response was linear in the investigated concentration range of 0-20 micrograms l-1 (r2 = 0.98). For plaice 47% of the selenium was extractable while the extraction efficiency for cod was 23%. The fish extracts were injected onto the column four times each and the variation in the quantitative data for different selenium-containing fractions between the runs was small (RSD < 10%). The recovery of selenium in the chromatographic step was about 70%, indicating some interaction between the fish extracts and the column material. Ultrafiltration using a membrane with a cut-off at M(r) 10,000 gave results similar to the size-exclusion fractionation, for cod about 20% of the soluble selenium had a M(r) < 10,000 and the corresponding value for plaice was 69%. Removal of high-molecular-weight compounds from the sample by trichloroacetic acid precipitation showed a similar proportion of low-molecular-weight compounds for plaice (77%), while the obtained value for cod was higher (38%) compared with the other techniques.

The aim of this study was to investigate whether consumption of a newly developed oat milk deprived of insoluble fiber would result in lower serum cholesterol and low-density lipoprotein (LDL) cholesterol levels in men with moderate hypercholesterolemia. The study had a randomized, controlled double-blind design, and oat milk was compared with an identically flavored control drink. Sixty-six men were recruited from a screening program and were randomly assigned to two groups. Each group took either oat milk or a control drink (rice milk) for 5 weeks (0.75 liters/day) and then switched to the other drink regimen for another 5-week period with a 5-week washout period between the test periods. The oat milk contained more dietary fiber, especially beta-glucan (0.5 g/100 g), than the control drink (<0.02 g/100 g). Both drinks were well appreciated and got similar sensory evaluation, indicating that the double-blind design had been attained. In the final analysis 52 subjects remained. Compared with the control drink, intake of oat milk resulted in significantly lower serum total cholesterol (6%, p = 0.005) and LDL cholesterol (6%, p = 0.036) levels. The decrease in LDL cholesterol was more pronounced if the starting value was higher (r = -0.55, p < 0.001). The concentration of high-density lipoprotein cholesterol was not significantly different after consumption of the two drinks. Serum triglycerides did not change significantly after intake of oat milk, but a significant increase was observed after intake of the control drink (p = 0.003). It is concluded that also oat milk deprived of insoluble fiber has cholesterol-reducing properties.

A drink based on oats has been developed with new technology. In this study the effects of this oat milk, soya milk and cow's milk on plasma lipid, glucose, insulin, and antioxidant status (measured as the ability of serum to suppress the formation of the radical cation ABTS*+) were compared in 24 healthy men and women. Half of the subjects (group A) consumed 0.75-1 liters/day of oat milk and soya milk for 4 weeks each, and the other half (group B) consumed oat milk and cow's milk for two 4-week periods. In the combined groups A plus B the oat milk regimen resulted in decreased plasma cholesterol (4%) and low-density lipoprotein (LDL) cholesterol (9%) levels as compared with baseline, but no changes in high-density lipoprotein cholesterol (HDL) and triglyceride values were observed. Also soya milk consumption resulted in decreased LDL cholesterol concentrations. The only significant plasma lipid change observed during consumption of cow's milk was an increase in HDL cholesterol. No consistent changes in body weight, fasting blood glucose, serum insulin, and antioxidant status occurred after consumption of any milk regimen. A significant correlation between baseline antioxidant status and total plasma cholesterol was found (r = -0.56). It is proposed that the high content of beta-glucans in oat milk was responsible for the decreased plasma cholesterol and LDL cholesterol concentrations, but the effect could also be due to a replacement of saturated fat in the customary diet by unsaturated fat. It is concluded that oat milk can be used as an alternative to other milk drinks by subjects who would benefit from reduced LDL cholesterol values.

The aim of the present study was to investigate whether oat saponins (avenacosides A and B) have any effect on the permeability of the rat intestine to actively and passively transported markers in vitro and in vivo. Intestinal segments were mounted in modified Ussing chambers, and the passage of the different marker compounds from the mucosal to the serosal side was measured for 120 min. Avenacosides (1 mg/ml) gave a significantly higher passage of the macromolecule ovalbumin and there was a tendency to increased passage of [14C]D-mannitol and [51Cr]EDTA. On the other hand, the saponins did not affect the active transport of [3H]methyl glucose. When rats were given saponins (40 mg/kg body weight) together with markers by gastric intubation, the passage of [51Cr]EDTA into blood and urine was somewhat reduced. For the macromolecule bovine serum albumin, no evident effect on the passage was observed in the presence of saponins. Thus, in contrast to the in vitro results, the in vivo marker passage seemed to be unaffected or even reduced in the presence of avenacosides. The study shows that saponins can affect the permeability of the rat intestine. However, this effect needs further investigation in vivo, especially regarding proteins.

The effects of oat saponins (a mixture of avenacosides A and B) and dietary fibre (cellulose and guar gum) on the disaccharidase activities in the proximal small intestine of the rat were investigated. The influence of avenacosides A and B on the activity of disaccharidases and alpha-amylase (EC 3.2.1.1) was also studied in vitro. In vivo, oat diets with three avenacoside contents (negligible, normal and twice normal) were used. No significant differences in sucrase (EC 3.2.1.48), maltase (EC 3.2.1.20), trehalase (EC 3.2.1.28) and lactase (EC 3.2.1.21) activities were found between the oat groups after 19 d feeding. The rats that were given cellulose tended to have higher disaccharidase activities compared with the other groups. The avenacosides inhibited the lactase activity significantly in vitro while no or small effects on the other disaccharidases were found. In contrast, the in vitro hydrolysis of starch by alpha-amylase was increased in the presence of saponins, probably due to their detergent effect. Thus, the in vitro studies showed that the avenacosides could influence the enzyme activities. In vivo, these effects are probably minor due to the low avenacoside concentrations found in oats.

The effects of oat saponins (a mixture of avenacosides A and B) on plasma and liver lipids in gerbils (Meriones unguiculatus) and rats were investigated. Cholesterol-containing diets high in total and saturated fat and with different avenacoside contents (zero (ethanol-extracted oats), normal (oats) and twice normal (ethanol-extracted oats plus added avenacosides)) were used. Compared with a cellulose control group the oat diets in both species gave a significantly higher cholesterol content in the HDL fraction and a significantly lower liver cholesterol content. No significant differences in total plasma cholesterol, HDL-cholesterol and plasma triacylglycerols were found, however, between the groups fed on oats with different avenacoside content. The liver weight, total liver cholesterol and free liver cholesterol were also similar, whereas the liver lipid content was significantly lower in rats given the highest amount of avenacosides compared with zero or normal amounts. The tendency was the same in gerbils. Thus, the oat saponins had only minor effects on lipid metabolism in gerbils and rats.