bluuebunny/crossref_metadata_2025 huggingface dataset:
Health benefits of low glycaemic index foods, such as pulses, in diabetic patients and healthy individuals
Authors: Rizkalla S. W. , Bellisle F. , Slama G.
Published: February 2003

The present paper covers the health benefits of low glycaemic index foods, such as pulses. Nutritional factors potentially play a crucial role in health and disease. A low-fat, high-carbohydrate diet is often recommended as a part of a healthy life-style. Historical works have shown that carbohydrate foods differ in their ability to affect post-ingestive glycaemia. The glycaemic index concept allows a ranking of carbohydrate-rich foods in terms of their blood glucose raising potential. Pulses are foods with very low glycaemic index values. Numerous studies have documented the health benefits that can be obtained by selecting foods of low glycaemic index. These benefits are of crucial importance in the dietary treatment of diabetes mellitus: glycaemic control is improved as well as several metabolic parameters, such as blood lipids. The results of human studies have been confirmed by animal experiments in the field of diabetes. Diets with low glycaemic index value improve the prevention of coronary heart disease in diabetic and healthy subjects. In obese or overweight individuals, low-glycaemic index meals increase satiety and facilitate the control of food intake. Selecting low glycaemic index foods has also demonstrated benefits for healthy persons in terms of post-prandial glucose and lipid metabolism. Several public health organizations have recently integrated consideration of the glycaemic index in their nutritional recommendations for patients with metabolic diseases and for the general population.
Pulses and lipaemia, short- and long-term effect: Potential in the prevention of cardiovascular disease
Authors: Anderson James W. , Major Amy W.
Published: February 2003

Cardiovascular disease (CVD) is the leading cause of death in most developed countries. Most CVD deaths are preventable through life-style measures such as diet, exercise and avoidance of cigarette smoking. Decreased intake of saturated fat and cholesterol and increased intake of cholesterol-reducing foods, such as pulses, deserve a high priority for activities designed to prevent CVD. Epidemiological and observational studies indicate that habitual intakes of large amounts of dietary fibre or of vegetables are associated with significantly lower rates of CVD. Studies over four decades document the hypocholesterolaemic effect of pulses and soyabeans. We performed a meta-analysis of eleven clinical trials that examined the effects of pulses (not including soyabeans) on serum lipoproteins. Intake of non-soya pulses was associated with these changes: fasting serum cholesterol, –7·2%, 95% CI –5·8, –8·6%; LDL–cholesterol, –6·2%, 95% CI –2·8, –9·5%; HDL–cholesterol, +2·6%, 95% CI +6·3, –1·0%; triacylglycerols, –16·6 %, 95% CI –11·8 %, –21·5 %; and body weight, –20·9%, 95% CI +2·2%, –4·1%. The hypocholesterolaemic effects of pulses appear related, in estimated order of importance, to these factors: soluble dietary fibre, vegetable protein, oligosaccharides, isoflavones, phospholipids and fatty acids, saponins and other factors. Intake of pulses may also reduce risk for CVD by favourable effects on blood pressure, glycaemia and risk for diabetes, and risk for obesity. Overall, the available evidence indicates that regular consumption of pulses may have important protective effects on risk for CVD.
Pulses and carcinogenesis: potential for the prevention of colon, breast and other cancers
Authors: Mathers John C.
Published: February 2003

Consumption of pulses as components of healthy diets is encouraged because it is believed that this is likely to help in reducing the risk of common non-communicable diseases, including cancers. However, the evidence base for the role of pulses in prevention of cancers is unconvincing because of the difficulties, using conventional epidemiological tools, in ascertaining the quantitative contribution made by pulses to cancer risk. Advances in understanding of the biological basis of cancer and of the mechanisms of action of cancer-preventing compounds offer new insights into the role of food-derived substances and of diet—gene interactions in modulating cancer risk. Pulses contain a rich variety of compounds which, if consumed in sufficient quantities, may help to reduce tumour risk.
New legume sources as therapeutic agents
Authors: Madar Zecharia , Stark Aliza H.
Published: February 2003

This review evaluates the potential health benefits of three legume sources that rarely appear in Western diets and are often overlooked as functional foods. Fenugreek (Trigonella foenum graecum) and isolated fenugreek fractions have been shown to act as hypoglycaemic and hypocholesterolaemic agents in both animal and human studies. The unique dietary fibre composition and high saponin content in fenugreek appears to be responsible for these therapeutic properties. Faba beans (Vicia faba) have lipid-lowering effects and may also be a good source of antioxidants and chemopreventive factors. Mung beans (Phaseolus aureus, Vigna radiatus) are thought to be beneficial as an antidiabetic, low glycaemic index food, rich in antioxidants. Evidence suggests that these three novel sources of legumes may provide health benefits when included in the daily diet.
Carbohydrate fractions of legumes: uses in human nutrition and potential for health
Authors: Guillon F. , Champ M. M.-J.
Published: February 2003

Starch and fibre can be extracted, using wet or dry processes, from a variety of grain legumes and used as ingredients for food. a-Galactosides can be isolated during wet processes from the soluble extract. Starch isolates or concentrates are mostly produced from peas, whereas dietary fibre fractions from peas and soyabean are commercially available. The physico-chemical characteristics of fibre fractions very much depend on their origin, outer fibres being very cellulosic whereas inner fibres contain a majority of pectic substances. Inner fibres are often used as texturing agents whereas outer fibres find their main uses in bakery and extruded products, where they can be introduced to increase the fibre content of the food. Most investigations on impacts on health have been performed on soyabean fibres. When positive observations were made on lipaemia, glucose tolerance or faecal excretion, they were unfortunately often obtained after non-realistic daily doses of fibres. Legume starches contain a higher amount of amylose than most cereal or tuber starches. This confers these starches a lower bioavailability than that of most starches, when raw or retrograded. Their low glycaemic index can be considered as beneficial for health and especially for the prevention of diseases related to insulin resistance. When partly retrograded, these starches can provide significant amount of butyrate to the colonic epithelium and may help in colon cancer prevention. a-Galactosides are usually considered as responsible for flatus but their apparent prebiotic effects may be an opportunity to valorize these oligosaccharides.
Non-nutrient bioactive substances of pulses
Authors: Champ Martine M.-J.
Published: February 2003

Pulses supply many bioactive substances found in minor amounts in food, but which may have significant metabolic and/or physiological effects. These compounds have long been classified as antinutritional factors, but many studies have reconsidered their impact on health. Some could play a role in the prevention of the major diseases of affluent societies. As these compounds can be beneficial or adverse, depending on conditions, an assessment of their various physiological effects is necessary to determine whether they should be preserved or eliminated in each main nutritional situation.
Effect of acute ingestion of fresh and stored lettuce (Lactuca sativa) on plasma total antioxidant capacity and antioxidant levels in human subjects
Authors: Serafini Mauro , Bugianesi Rossana , Salucci Monica , Azzini Elena , Raguzzini Anna , Maiani Giuseppe
Published: February 2003

The present study investigated whether storage under modified-atmosphere packaging (MAP) affected the antioxidant properties of fresh lettuce (Lactuca sativa). Eleven healthy volunteers (six men, five women) consumed 250 g fresh lettuce, and blood was sampled before (0 h) and 2, 3 and 6 h after consumption. The protocol was repeated 3 d later with the same lettuce stored at 5°C under MAP conditions (O2–N2(5:95, v/v)). Results showed that after ingestion of fresh lettuce, plasma total radical-trapping antioxidant potential (TRAP), measured as area under the curve, was significantly higher (1·3 (SEM 0·3) MMOL/L PER 6 H;P<0·05) THAN THE VALUE OBTAINED WITH MAP-STORED LETTUCE (0·1 (sem 0·2) mmol/l per 6 h). Plasma TRAP, quercetin andp-coumaric acid were significantly different from baseline values (P≤0·05) 2 and 3 h after fresh lettuce ingestion. Caffeic acid increased significantly at 3 h (P<0·05). Plasma β-carotene levels increased significantly at 6 h (P<0·05). Vitamin C concentrations (mg/l) rose from 10·9 (sem 2·0) to 12·7 (sem 3·0) (P<0·001), 12·7 (sem 2·0) (P<0·01) and 12·9 (sem 3·0) (P<0·05) at 0, 2, 3 and 6 h respectively. No changes were observed after ingestion of MAP-stored lettuce for all the measured markers. Our present results showed that ingestion of MAP-stored lettuce does not modify plasma redox status in healthy subjects. Further research is needed to develop post-harvesting techniques able to preserve the bioactive molecule content of plant food.
Evidence that glutamine modulates respiratory burst in stressed rat polymorphonuclear cells through its metabolism into arginine
Authors: Moinard Christophe , Caldefie-Chezet Florence , Walrand Stephane , Vasson Marie-Paule , Cynober Luc
Published: February 2003

Glutamine (GLN) and arginine (ARG) are recognized for their ability to modulate immune cell function. However, the metabolic pathways involved in their action remain unclear. It was recently shown that GLN- or ARG-enriched diets increased radical oxygen species (ROS) production by neutrophils from stressed rats. Since these two amino acids have a tied metabolism, we hypothesized that conversion between GLN and ARG (and its active metabolites NO•and polyamines) might be involved. To test this hypothesis male Sprague–Dawley rats (n117) were randomized into thirteen groups: rats in eleven groups were rendered catabolic by dexamethasone injection (1·5 mg/kg per d for 5 d) and 6·8 mmol either GLN, ARG or non-essential amino acids (NEAA; glycine, alanine and histidine)/kg per d were given by the enteral route; one group was pair-fed to the treated groups. The regimens of all the groups were rendered isonitrogenous by the addition of NEAA. The last group was not treated and was fedad libitum. For each supplementation three subgroups were formed, each of which received a specific inhibitor: methionine sulfoximine (inhibitor of GLN synthase; 100 mg/kg per d), S-methylthiourea (inhibitor of inducible NO•synthase (iNOS); 50 mg/kg per d) and difluoromethylornithine (inhibitor of ornithine decarboxylase (ODC); 50 mg/kg per d). Oxidative metabolism, intracellular H2O2, and extracellular O2•-production were measured in unstimulated and phorbol myristate acetate-stimulated polymorphonuclear neutrophils. GLN- and ARG-enriched diets increased respiratory burst by neutrophils (oxidative metabolism of 152 (SEM 24) AND 138 (sem 45)v.57 (sem 18) mV for GLN-, ARG- and NEAA-enriched diets respectively,P<0·05).In vivoinhibition of iNOS or ODC decreased ROS production induced by GLN and ARG.In vivoinhibition of GLN synthase did not modify the effect of ARG on ROS production. In conclusion, GLN and ARG modulate ROS production in neutrophils from stressed rats by the same pathway involving polyamine and NO•synthesis.
Effects of dietary fat and conjugated linoleic acid on plasma metabolite concentrations and metabolic responses to homeostatic signals in pigs
Authors: Ostrowska E. , Cross R. F. , Muralitharan M. , Bauman D. E. , Dunshea F. R.
Published: February 2003

Sixteen female cross-bred (Large White × Landrace) pigs (initial weight 65 kg) with venous catheters were randomly allocated to four treatment groups in a 2×2 factorial design. The respective factors were dietary fat (25 or 100 g/kg) and dietary conjugated linoleic acid (CLA; 0 or 10 g CLA-55/kg). Pigs were fed every 3 h (close toad libitumdigestible energy intake) for 8 d and were bled frequently. Plasma glucose and non-esterified fatty acid (NEFA) responses to insulin and adrenaline challenges were determined on day 8. Plasma concentrations of NEFA were significantly increased (10·5 and 5·4 % for low- and high-fat diets respectively,P=0·015) throughout the experiment, suggesting that there was a possible increase in fat mobilisation. The increase in lipolysis, an indicator of ß-adrenergic stimulated lipolysis, was also evident in the NEFA response to adrenaline. However, the increase in plasma triacylglycerol (11·0 and 7·1 % for low- and high-fat diets respectively,P=0·008) indicated that CLA could have reduced fat accretion via decreased adipose tissue triacylglycerol synthesis from preformed fatty acids, possibly through reduced lipoprotein lipase activity. Plasma glucose, the primary substrate forde novolipid synthesis, and plasma insulin levels were unaffected by dietary CLA suggesting thatde novolipid synthesis was largely unaffected (P=0·24 andP=0·30 respectively). In addition, the dietary CLA had no effect upon the ability of insulin to stimulate glucose removal.
Effects of dietary fat source and breed on the carcass composition,n-3 polyunsaturated fatty acid and conjugated linoleic acid content of sheep meat and adipose tissue
Authors: Wachira A. M. , Sinclair L. A. , Wilkinson R. G. , Enser M. , Wood J. D. , Fisher A. V.
Published: February 2003

Seventy-two 8-week-old ram lambs from three breeds, Suffolk, Soay and Friesland, were offered one of four diets based on dried grass and formulated to have a similar fatty acid content (60 g/kg DM) and containing: Megalac (high in 16 : 0, control; Volac Ltd, Royston, Herts., UK), whole linseed (18 : 3n-3), fish oil (20 : 5n-3 and 22 : 6n-3) or whole linseed plus fish oil. The lambs were slaughtered at approximately half of their mature live weight (43, 21 and 43 kg for Suffolk, Soay and Friesland lambs, respectively). Fish oil reduced DM intake and lamb live-weight gain (P<0·001), while DM intake, live-weight gain and subcutaneous fat content were highest in Suffolk and lowest in Soay lambs. Linseed feeding doubled the proportion (×100) of 18 : 3n-3 in thelongissimus dorsifrom 1·4 to 3·1 and in the subcutaneous adipose tissue from 1·2 to 2·6 (P<0·001). Suffolk and particularly Soay lambs contained higher proportions of 18 : 3n-3 than Friesland lambs in thelongissimus dorsi, while in the adipose tissue, Suffolk lambs had the highest level. Feeding fish oil increased the muscle proportion (×100) of 20 : 5n-3 from 0·7 to 2·3 and 22 : 6n-3 from 0·3 to 0·8 (P<0·001). By contrast, the proportions of the longer-chainn-3 polyunsaturated fatty acids were similar across all three breeds. All three lipid supplements containingn-3 polyunsaturated fatty acids increased the content of muscletrans-18 : 1 relative to the control values, but conjugated linoleic acid (cis-9,trans-11–18 : 2) only increased in the muscle of lambs fed linseed. Feeding linseed or fish oil lowered then-6 :n-3 ratio in sheep meat, but neither diet nor breed had much effect on the polyunsaturated fatty acid: saturated fatty acid ratio.
Food and macronutrient intake of male adolescent Kalenjin runners in Kenya
Authors: Christensen Dirk L. , van Hall Gerrit , Hambraeus Leif
Published: February 2003

A nutritional survey based on twelve adolescent male Kalenjin runners in Kenya during a 2-week field study was carried out in order to determine the composition of their diet and make a comparison with macronutrient recommendations for athletes. Food samples were collected for analysis of macronutrient distribution and energy content from main meals and the macronutrient distribution and energy content of additional food intake were based on the information of a 24 h recall interview and estimated from food tables. The diet of the Kalenjin runners was very high in carbohydrate (71 % 8·7 g/kg body weight per d) and very low in fat (15 %). Intake of total protein (13 %; 1·6 g/kg body weight per d) was above the daily intake recommended by the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU), while essential amino acid intake was estimated to be in the borderline-to-low range based on FAO/WHO/UNU recommendations for children <12 years and adults. The energy intake was mainly derived from vegetable sources (90 %) with maize and kidney beans as the staple food (81 %). The diet of the Kalenjin runners met recommendations for endurance athletes for total protein and most essential amino acid intake as well as carbohydrate intake even though it was based on a small range of food items.
Relationship between tissue lipid peroxidation and peroxidizability index after α-linolenic, eicosapentaenoic, or docosahexaenoic acid intake in rats
Authors: Saito Morio , Kubo Kazuhiro
Published: February 2003

In a previous study, we found that the extent of dietaryn-3 docosahexaenoic acid (DHA)-stimulated tissue lipid peroxidation was less than expected from the relative peroxidizability index of the total tissue lipids in rats with adequate vitamin E nutritional status. This suppression of lipid peroxidation was especially prominent in the liver. To elucidate whether this phenomenon was unique to DHA, we compared the peroxidation effects ofn-3 α-linolenic acid (α-LN) andn-3 eicosapentaeonic acid (EPA) with those of DHA in rats. Either α-LN (8·6 % of total energy), EPA (8·2 %), or DHA (8·0 %) and one of two levels of dietary vitamin E (7·5 and 54 mg/kg diet) were fed to rats for 22 d. Levels of conjugated diene, chemiluminescence emission and thiobarbituric acid (TBA)-reactive substance in the liver, kidney, and testis were determined as indicators of lipid peroxidation. In rats fed the DHA diet deficient in vitamin E (7·5 m/g diet), TBA values in the liver, kidney, and testis correlated well with the tissues' relative peroxidizability indices. In rats fed the α-LN diet with an adequate level of vitamin E (54 m/g diet), a close association between relative peroxidizability indices and lipid peroxide levels was observed in all the tissues analysed. However, in rats fed either the EPA diet or the DHA diet with an adequate level of vitamin E, the extent of lipid peroxidation in each tissue was less than expected from the relative peroxidizability index. This suppression was particularly marked in the liver. We concluded that suppression of lipid peroxidation below the relative peroxidizability index was not unique to DHA, but was also seen with EPA, which has five double bonds, in rats with adequate vitamin E nutritional status, but not with α-LN, which has three double bonds.
Dietary interrelationships among arginine, methionine, and lysine in young broiler chicks
Authors: Chamruspollert M. , Pesti G. M. , Bakalli R. I.
Published: February 2003

Since excess dietary lysine (Lys) can increase the chick's arginine (Arg) requirement and excess Arg can increase the chick's methionine (Met) requirement, experiments were conducted to test the hypothesis that responses to dietary Lys and Met are also interrelated. Day-old Ross × Ross chicks were fed a maize–soyabean meal-based diet supplemented with four levels of L-Arg (0, 5, 10 or 20 g/kg), factorially arranged with four levels of supplemental DL-Met (0, 1, 2 or 3 g/kg). Three replicate pens of ten chicks each were randomly assigned to each treatment and fed for 14 d. An increase in Arg in the diet caused growth and feed-intake depression (P=0·0001), but increasing Met in the diet enhanced growth and feed intake (P=0·0001). Arg toxicity was dependent on the Met level of the diet (Arg × Met interaction;P=0·0153). Experiment 2 was conducted to study interrelationships among Arg, Met, and Lys. Eight treatments were factorially combined: two levels of supplemental L-Arg (0 or 10 g/kg), two levels of supplemental DL-Met (0 or 2 g/kg), and two levels of supplemental L-Lys (0 or 6 g/kg). Six replicate pens of eight chicks per treatment were used. A three-way interaction among Arg, Met, and Lys was observed for body-weight gain and feed intake (P<0·023). As expected, kidney arginase activity increased as dietary Lys increased (P=0·0004). No interactions were found for kidney arginase activity. Muscle creatine increased when chicks were fed the higher Arg (25·2 g/kg) diet (P=0·0047). A three-way interaction among Arg, Met, and Lys was found for muscle creatine (P=0·0075). Excess dietary Lys depressed muscle creatinine concentration, but only in the presence of the lower concentrations of Arg and Met. To conclude, an interrelationship among Arg, Met, and Lys was demonstrated, and it was probably related to creatine biosynthesis.
The effect of different cooking methods on folate retention in various foods that are amongst the major contributors to folate intake in the UK diet
Authors: McKillop Derek J. , Pentieva Kristina , Daly Donna , McPartlin Joseph M. , Hughes Joan , Strain J. J. , Scott John M. , McNulty Helene
Published: February 2003

Folate intake is strongly influenced by various methods of cooking that can degrade the natural forms of the vitamin in foods. The aim of the present study was to determine the effect of different cooking methods on folate retention in various foods that contribute to folate intake in the UK diet. Typical purchasing and cooking practices of representative food folate sources were determined from a questionnaire survey of local shoppers (n 100). Total folate was determined by microbiological assay (Lactobacillus casei NCIMB 10463) following thermal extraction and tri-enzyme (α-amylase, protease and conjugase) treatment in raw foods and after typical methods of cooking. Boiling for typical time periods resulted in only 49 % retention of folate in spinach (191·8 and 94·4 μg/100 g for raw and boiled spinach respectively; P<0·005), and only 44 % in broccoli (177·1 and 77·0 μg/100 g for raw and boiled broccoli respectively, P<0·0001). Steaming of spinach or broccoli, in contrast, resulted in no significant decrease in folate content, even for the maximum steaming periods of 4·5 min (spinach) and 15·0 min (broccoli). Prolonged grilling of beef for the maximum period of 16·0 min did not result in a significant decrease in folate content (54·3 and 51·5 μg/100 g for raw and grilled beef respectively). Compared with raw values, boiling of whole potatoes (skin and flesh) for 60·0 min did not result in a significant change in folate content (125·1 and 102·8 μg/100 g for raw and boiled potato respectively), nor was there any effect on folate retention whether or not skin was retained during boiling. These current results show that the retention of folate in various foods is highly dependent both on the food in question and the method of cooking. Thus, public health efforts to increase folate intake in order to improve folate status should incorporate practical advice on cooking.
Modulation of ovomucoid-specific oral tolerance in mice fed plant extracts containing lectins
Authors: Kjær Tanja M. R. , Frøkiær Hanne
Published: February 2003

We investigated the effect of feeding extracts of four different legumes (red kidney bean (Phaseolus vulgaris), peanut (Arachis hypogaea), soyabean (Glycine max) and pea (Pisum sativum) on the specific immune response against a food protein. Mice were fed ovomucoid and the specific immune response was evaluated. Ovomucoid fed alone resulted in oral tolerance induction measured as both a reduced ovomucoid-specific spleen cell proliferation and antibody response. Feeding kidney-bean extract prevented induction of oral tolerance to ovomucoid measured as spleen cell proliferationin vitro. Pure kidney-bean lectin also prevented oral tolerance induction, suggesting that lectin in the kidney-bean extract caused inhibition of oral tolerance. Parenteral administration (intravenous and intraperitoneal) of pure kidney-bean lectin had no significant influence on oral tolerance induction. Soyabean extract also influenced the immune response against ovomucoid; however, this was not as pronounced as for kidney bean and was only significant (P<0·001) for the antibody response. No effect was observed when pea extract was fed and peanut extract had a non-significant effect on induction of oral tolerance and on the general immune response. Plasma antibodies against kidney-bean lectin, but not against the three other legume lectins, were detected. Our current findings show that other dietary components can influence the specific immune response against food proteins. Various dietary components may thus contribute to the onset of adverse immunological responses.
Effects of fish oil- and olive oil-rich diets on iron metabolism and oxidative stress in the rat
Authors: Miret S. , Sáiz M. P. , Mitjavila M. T.
Published: February 2003

The objective of the present study was to examine the effects of fish oil (FO)- and olive oil (OO)-rich diets on Fe metabolism and oxidative stress. Rats were fed for 16 weeks with diets containing 50 g lipid/g; either OO, maize oil (MO) or FO. OO or MO diets contained a standard amount (100 m/g) of all-rac-α-tocopheryl acetate. FO diets were supplemented with 0, 100 or 200 mg all-rac-α-tocopheryl acetat/g (FO-0, FO-1 or FO-2 diets, respectively). At the end of the feeding period, we measured non-haem Fe stores in liver and spleen, and erythrocyte and reticulocyte count. We also determined antioxidants and products derived from lipid peroxidation in plasma and erythrocytes. Our results showed reduced non-haem Fe stores in rats fed any of the FO diets. Reticulocyte percentage was higher in the rats fed FO-0 and FO-1. Plasma α-tocopherol was very low in rats fed the FO-0 diet. Rats fed the FO-1 and FO-2 diets showed higher α-tocopherol in plasma than the FO-0 group but lower than the MO or OO groups. We did not observe such differences in the α-tocopherol content in erythrocyte membranes. Superoxide dismutase and glutathione peroxidase activities were lower in the erythrocytes of rats fed the FO-0 diet. The products derived from lipid peroxidation were also higher in the FO groups. The administration of FO-rich diets increased lipid peroxidation and affected Fe metabolism. On the other hand, the OO-rich diet did not increase oxidative stress and did not alter Fe metabolism. Based on these results, we conclude that FO supplementation should be advised carefully.
Acute-on-chronic effects of fatty acids on intestinal triacylglycerol-rich lipoprotein metabolism
Authors: Black Irene L. , Roche Helen M. , Tully Anne-Marie , Gibney Michael J.
Published: February 2003

Postprandial triacylglycerol (TAG) metabolism is an important metabolic state that has been associated with cardiovascular disease. The magnitude of the postprandial TAG response is determined by dietary fat composition, which alters intestinal and hepatic TAG-rich lipoprotein (TRL) metabolism. Caco-2 cell monolayers are morphologically and physiologically similar to the human intestinal enterocytes, hence they are a good model to study intestinal lipoprotein metabolism. To date only the acute effect of fatty acid composition on intestinal TRL metabolism in Caco-2 cells has been investigated. Little is known of the effect of habitual, or chronic, dietary fat composition on intestinal TRL metabolism. Using the Caco-2 cell model, the present study investigated the acute-on-chronic effect of fatty acid composition on TRL metabolism. Caco-2 cells were grown in the presence of 0·05 mM-PALMITIC ACID (PA; 16 : 0), -OLEIC ACID (OA; 18 : 1N-9),-EICOSAPENTAENOIC ACID (EPA; 20 : 5N-3) OR NO FATTY ACID (CONTROL) FOR 19 D, THEN ONE OF FOUR ACUTE TREATMENTS (CONTROL (BOVINE SERUM ALBUMIN (BSA; 5 G/L)) OR BSA (5 G/L) PLUS 0·5 Mm-PA, -OA or -EPA) were administered for 22 h. Significant acute×chronic interactions for the effect of fatty acid composition on cellular TAG:secretedde novoTAG, and cellularde novoTAG:de novophospholipid were observed. Thus the effect of a fatty acid was determined by the duration of exposure to the fatty acid intervention. Acute PA treatment increasedde novoTAG synthesis, but chronic PA supplementation did not. Acute and chronic OA treatments increasedde novoTAG secretion. For EPA, chronic supplementation had the greatest effect on TAG synthesis and secretion. The acute-on-chronic effects of fatty acids on apolipoprotein B metabolism were relatively minor compared with the changes noted for TRL lipid composition. The present study shows that the Caco-2 cell model is valuable for studying intestinal TRL metabolism and that fatty acids modulate this process, the nature of which can be determined by the length of exposure of the cell to the fatty acid.
Unhealthy eating habits, physical exercise and macronutrient intakes are predictors of anthropometric indicators in the Women's Health Trial: Feasibility Study in Minority Populations
Authors: Bhargava Alok , Guthrie Joanne F.
Published: February 2003

The increasing prevalence of obesity in the USA, especially among minority populations, is a serious public health concern. This present study analysed repeated measurements at baseline and at 6 and 12 months on 351 women in the control group and 575 women in the intervention group of the Women's Health Trial: Feasibility Study in Minority Populations. Dynamic random effects models were estimated using the three repeated observations to explain the effects of energy and macronutrient intakes, physical exercise, unhealthy eating habits and socio-economic characteristics on the subjects' body weights and waist and hip circumferences. In both the control and intervention groups, physical exercise was negatively associated with body weight and with waist and hip circumferences, while an index of unhealthy eating habits was positively associated (P<0·05). The proportion of energy derived from carbohydrate and from saturated and monounsaturated fat were often significant predictors of body weight and of waist and hip circumferences in the two groups. The results indicated that nutrition education programmes for improving eating habits and increasing physical exercise can reduce obesity prevalence in the USA.
Intraruminal propionate supplementation modifies hindlimb energy metabolism without changing the splanchnic release of glucose in growing lambs
Authors: Majdoub Linda , Vermorel Michel , Ortigues-Marty Isabelle
Published: February 2003

The influence of propionate supplementation on the splanchnic metabolism of energy-yielding nutrients and the supply of glucose to the hindlimb was investigated in growing lambs. Six rumen-cannulated and multicatheterized lambs (32·2 kg), fed frozen rye grass at 690 kJ metabolizable energy intak/ per kg body weight0·75, were infused intraruminally with a salt solution (control) or with propionate solutions at 0·55 mo/ (P1) or 0·98 mo/ (P2) according to a replicated Latin square design. In the rumen fluid, supplementation decreased the acetate:propionate molar ratio from 2·36:1 to 1·37:1, without modifying the ruminal concentrations of acetate and NH4. As a result, the portal appearance of propionate increased by 51 and 72 % with P1 and P2, respectively, and that of L-LACTATE DOUBLED. ACROSS THE Liver, net extraction of propionate increased by 47 and 67 % with P1 and P2, respectively. However, the net hepatic production of glucose remained unchanged, probably as the result of a substantial rise in insulin secretion and its hepatic extraction. Overall, the net splanchnic release of acetate, glucose and butyrate was not modified while that of L-lactate increased. Despite this, the net uptake of acetate, glucose, l-lactate and non-esterified fatty acids by the hindlimb increased. Propionate probably enhanced the storage of energy-yielding nutrients in the hindlimb, despite their unchanged release by the splanchnic tissues and the unmodified insulinaemia. Regulatory mechanisms are not clear.
Pre- and postprandial changes in plasma hormone and metabolite levels and hepatic deiodinase activities in meal-fed broiler chickens
Authors: Buyse Johan , Janssens Kristel , Van der Geyten Serge , Van As Pieter , Decuypere Eddy , Darras Veerle M.
Published: February 2003

The present study aimed to study the effects of food deprivation and subsequent postprandial changes in plasma somatotrophic and thyrotrophic hormone levels and focused on the inter-relationships between these hormonal axes and representative metabolites of the intermediary metabolism of meal-fed broiler chickens. Male broiler chickens (2 weeks old) were fed a meal of 40–45 g/bird per d for two consecutive weeks (food-restricted (FR) treatment). The daily allowance was consumed in about 30 min. At 4 weeks of age, FR chickens were killed at several time intervals (ten per sampling time) in relation to the daily food allowance: before feeding (about 23·5 h of food deprivation), and at 10, 20, 30 (end of feeding), 40, 50, 60, 90, 120 and 200 min after initiation of feeding. Birds fed ad libitum served as controls (ad-libitum (AL) treatment). Liver tissue was collected for deiodinase type I and type III activity measurements and blood samples for analysis of growth hormone (GH), insulin-like growth factor (IGF)-I, thyroxine (T4), 3,3′,5-triiodothyronine (T3), glucose, non-esterified fatty acids (NEFA), uric acid, triacylglycerol (TG) and lactate levels. Food deprivation caused a shift from lipogenesis to lipolysis and increased fatty acid turnover, a reduction in protein anabolism and reduced metabolic rate. Food intake was followed immediately by a pronounced increase in metabolic rate, initially mainly based on anaerobic mechanisms. Refeeding gradually reversed the fasting-induced alterations in plasma hormone and metabolite levels, but the time course of changes differed between metabolites, which clearly preceded those of the hormones investigated. The order of responsiveness after food provision were glucose>uric acid≥NEFA>lactate>TG for the plasma metabolites and GH>T3>T4>IGF–I for hormones. Based on these different postprandial time courses, several functional relationships are proposed. Glucose is believed to be the primary trigger for the normalisation of the effects of fasting on these plasma variables by restoring hepatic GH receptor capacity, as well as decreasing deiodinase type III activity.
Redistribution of abdominal fat after a period of food restriction in rats is related to the type of dietary fat
Authors: Soriguer Federico , Moreno Felisa , Rojo-Martínez Gemma , Cardona Fernando , Tinahones Francisco , Gómez-Zumaquero Juan M. , García-Fuentes Eduardo , Morcillo Sonsoles
Published: February 2003

The aim of the present experiment was to test the hypothesis that during refeeding a redistribution of intra-abdominal fat takes place and that both the recovery of weight and the redistribution of intra-abdominal fat are related to the type of dietary fat. The experimental study was carried out using male Sprague–Dawley rats. Three groups of animals were fed diets with three different fatty acid profiles. Each group contained two branches, one fed normally and the other fed initially with a 50 % energy reduction followed by refeedingad libitumwith the same isoenergetic diet as the control branch, giving a total of six treatments. Measurements were made of the final and incremental weight of the rat, weight of the intra-abdominal adipose tissue (total intra-abdominal, epididymal, omental and retroperitoneal adipose tissue weight), and feed efficacy (weight incremen/etabolizable energy intake). Carcass, epididymal, omental, and muscle lipid contents, carcass protein and energy density were also measured. The results revealed that diets rich in fish oil or olive oil increase catch-up growth more than diets rich in saturated fats. During refeeding the lipid content in the adipose tissue increases while that of muscle tissue decreases. A diet rich in saturated fats induces a relative increase in the amount of intra-abdominal adipose tissue. The lipid content in adipose and muscle tissues and the distribution of intra-abdominal fat can all be modified by the type of dietary fat.
Ewe–lamb bonding behaviours at birth are affected by maternal undernutrition in pregnancy
Authors: Dwyer Cathy M. , Lawrence Alistair B. , Bishop Stephen C. , Lewis Mitch
Published: February 2003

Maternal undernutrition in pregnancy results in low birth-weights and impaired postnatal survival in sheep. Largely anecdotal evidence suggests that the expression of appropriate maternal and neonate behaviours may also be disrupted by undernutrition. In the present study, we investigated the effect of a moderate (35 %) reduction in ewe nutritional intake in pregnancy on the expression of ewe–lamb bonding behaviours in primiparous Scottish Blackface ewes. Low-intake (L) ewes had significantly higher plasma progesterone than high-intake (H) ewes from mid-gestation onwards (e.g. plasma progesterone at 20 weeks (n/l): H 15·72, L 22·38, SED 1·80, P<0·001), AND A LOWER OESTRADIOL: PROGESTERONE VALUE THAN H EWES AT DELIVERY (H 0·46, L 0·35, sed 0·05, P<0·05). Lamb birth-weight was reduced in the L lambs compared with H lambs (mean body weight (kg): H 3·31, L 3·00, sed 0·14, P<0·05), but the incidence of malpresentation at delivery was greater in L lambs. L ewes spent significantly less time licking their lambs than H ewes after delivery (time grooming in 2 h after birth (%): H 56·12, L 48·17, sed 2·639, P<0·01) and were more aggressive towards the lambs. Lamb behaviours were not directly affected by maternal nutritional treatment, but lamb birth-weight had a significant effect on neonatal developmental progress. Low-birth-weight lambs were slower than heavier lambs to stand and sucked less frequently. In tests of maternal attachment to the lamb, H ewes received higher scores than L ewes at both 24 h after birth (ewes receiving high scores (%): H 41·3, L 21·4, P<0·05) and at 3 d postnatal. We conclude that even a moderate level of undernutrition impairs the attachment between ewes and lambs by affecting maternal behaviours expressed at birth. In addition, the results suggest that levels of nutrition resulting in a decrease in birth weight will affect neonatal lamb behavioural progress.
Serum fatty acid levels, dietary style and coronary heart disease in three neighbouring areas in Japan: the Kumihama study
Authors: Nakamura Tomoki , Azuma Akihiro , Kuribayashi Toshiro , Sugihara Hiroki , Okuda Seisuke , Nakagawa Masao
Published: February 2003

CHD mortality is extremely low in Japan, particularly in rural districts, when compared with that in Western countries. This has been partly attributed to the difference in dietary lifestyle. We investigated the factors influencing CHD mortality in a rural coastal district of Japan, comprising mercantile, farming, and fishing areas with distinct dietary habits. We prospectively examined the incidence of CHD from 1994 to 1998, as well as coronary risk factors and serum fatty acid concentrations. The incidence of angina pectoris was significantly (P=0·01) lower in the fishing area than in the mercantile and farming areas. Blood pressure, physical activity, prevalence of diabetes, serum levels of uric acid and HDL-cholesterol were similar between the three areas. Total- and LDL-cholesterol levels were significantly lower but the smoking rate was markedly higher in the fishing area than in the other two areas. Serum levels of saturated fatty acids andn−6 polyunsaturated fatty acids (PUFA) were lowest in the fishing area, butn−3 PUFA did not differ significantly. Then−6:n−3 PUFA ratio was lowest and eicosapentaenoic:arachidonic acid was highest in the fishing area. Although many previous studies have emphasized the beneficial effect ofn−3 PUFA in preventing CHD, the present study indicated that a lower intake ofn−6 PUFA and saturated fatty acids has an additional preventive effect on CHD even when the serum level ofn−3 PUFA is high because of high dietary fish consumption.
Carbohydrate–energy restriction may protect the rat brain against oxidative damage and improve physical performance
Authors: de Oliveira S. L. , Diniz D. B. , Amaya-Farfan J.
Published: February 2003

Chronic energy restriction, α-tocopherol supplementation and their interaction with exhaustive exercise were investigated. Eleven-week-old male Wistar rats (n 6×10) were fed either a control (C), a 30 % carbohydrate-energy-restricted control (R) or an α-tocopherol-supplemented (S) diet for 5 months. The animals in each diet were divided into exercised (E) and non-exercised (NE) groups. Before killing, the exercised rats were required to run to exhaustion (39 (SE 6), 69 (se 11) and 18 (se 2) min for the C, R and S groups, respectively). Lipid peroxidation (thiobarbituric acid-reactive substances; TBARS), protein damage (reactive carbonyls) and α-tocopherol were determined in gastrocnemius, liver, brain an/r plasma. There was no difference in lipid peroxidation between the R and C groups, but in liver and muscle peroxidation appeared significantly lower in the S than the other two diets. TBARS in the brain were similar in all groups. On the other hand, reactive carbonyls showed that both the R and S diets reduced protein damage in the brain, while exhaustive exercise increased it. For liver and muscle, however, reactive carbonyl levels were similar in all groups. α-Tocopherol supplementation increased the vitamin concentrations in liver, muscle and plasma, but exercise decreased them in plasma and brain. Carbohydrate-energy restriction increased (P=0·0025) resistance to exhaustive exercise considerably without depleting stores of α-tocopherol or exacerbating oxidative damage in monitored tissues. It is concluded that while exhaustive exercise promotes a tissue-specific oxidative damage detectable only in brain proteins, both experimental diets tended to ameliorate this condition.
Possible effects of pollock and herring on the growth and reproductive success of Steller sea lions (Eumetopias jubatus): insights from feeding experiments using an alternative animal model,Rattus norvegicus
Authors: Donnelly Carolyn P. , Trites A. W. , Kitts D. D.
Published: February 2003

The decline of Steller sea lions (Eumetopias jubatus) in the Gulf of Alaska appears to have been associated with a switch of diet from one dominated by fatty forage fishes (such as herring;Clupea pallasi) to one dominated by low-fat fish (such as pollock;Theragra chalcogramma). Observations made during the decline include reduced body size of sea lions, low pregnancy rates, and high mortality. We used the general mammalian model, the laboratory rat (Rattus norvegicus), to test whether changing the quality of prey consumed could cause changes in size and reproductive performance. Five groups of twelve female, weanling rats were fed diets composed of herring (H), pollock (P), pollock supplemented with herring oil (PH), pollock supplemented with pollock oil (PP), or a semi-purified diet (ICN). Mean body weights were greatest for H, followed by PH, P, PP and finally ICN, although ICN was the only group significantly different from the others (P<0·05). Food intakes before mating were 10 % higher for groups on the lower-fat diets (P and ICN), resulting in similar energy intakes in all groups. The protein efficiency ratio was highest for the H diet, slightly lower for all pollock diets, and significantly lower for ICN (P<0·05). The fetal weights for mothers fed P were significantly reduced (P<0·05). The present study shows that the energy content was a major limiting factor in the nutritional quality of pollock. When food intake was adjusted to meet energetic requirements, there were no detrimental consequences from eating pollock. However, supplementation of pollock meal with additional pollock oil may reduce growth and reproductive performance, although the reasons for this were not apparent.
Effects of feed intake on composition of sheep rumen contents and their microbial population size
Authors: Rodríguez C. A. , González J. , Alvir M. R. , Redondo R. , Cajarville C.
Published: February 2003

The present study was conducted to determine the effect of feed intake on the composition of the rumen contents of sheep and on their bacterial densities. Whole rumen contents were sampled after a period of continuous inter-rumen infusion of15NH3from four rumen-cannulated wethers successively fed on a hay–concentrate diet (2:1, / on a DM basis) at two rates of feed intake: 40 and 80 g D/g body weight0·75. Total weight and chemical composition of rumen contents, as well as the distribution by size and chemical composition of particles, were determined. The populations of bacteria associated with the liquid (liquid-associated bacteria, LAB) and solid (solid-associated bacteria, SAB) fractions of rumen digesta and the distribution of SAB according to feed particle size were also examined. The greater feed intake caused an increase in the mass of the rumen contents, while its chemical composition did not change, except for a higher content of organic matter (P=0·023). The distribution of feed particles by size was similar at both levels of intake. The concentrations of neutral- and acid-detergent fibre in feed particles decreased and those of total, dietary, and microbial N increased, both with a quadratic response (P=0·001), as particle size decreased. The proportion of LAB in the microbial biomass of rumen digesta reached only 8·0 %. This proportion and the density of LAB were unaffected by the level of feed intake, whereas an apparent reduction (10·4 %) occurred with the SAB biomass in whole rumen contents. A systematic, but not significant, reduction (mean value 11·9 %) in the level of microbial colonisation in the different particle fractions with the increase of feed intake was also observed.
The hepatic retinyl ester hydrolase activity is depressed at the onset of diabetes in BB rats
Authors: Chen Min , Thomson Alan B. R. , Tsin Andrew T. C. , Basu Tapan K.
Published: February 2003

Dietary vitamin A as retinyl ester is hydrolysed and re-esterified with long-chain fatty acids in the small intestine. The esterified vitamin A is subsequently stored in the liver, where it is hydrolysed to free retinol to be transported by carrier proteins to the target tissue. A decreased availability of retinol carrier proteins has been suggested to be responsible for affecting metabolic availability of vitamin A in type 1 diabetes. Using BB Wistar rats, the present study was undertaken to examine whether the presence of a hyperglycaemic state modifies retinyl ester hydrolase (REH) activity in the intestine and the liver. At the onset of diabetes, hepatic REH enzymatic activity was significantly (P<0·05) decreased. However, REH activity remained unaffected in the small intestine, including both ileum and jejunum. Diabetes also resulted in decreased plasma and liver concentrations of retinol. Anin vitrostudy was conducted to examine the effect of diabetes on the intestinal uptake of retinyl palmitate. Jejunum and ileum from diabetic and non-diabetic BB rats were incubated with labelled retinyl palmitate at different concentrations ranging from 32 to 256 nmol/l. The uptake of retinyl palmitate was increased in both diabetic and non-diabetic rats together with the increase of substrate concentration. However, no significant difference was observed in the uptake of retinyl palmitate between diabetic and non-diabetic rats. These present results suggest that the depressed hepatic REH activities may contribute to the diabetes-associated metabolic derangement of vitamin A.