bluuebunny/crossref_metadata_2025 huggingface dataset:
Dietary Factors and Body Mass Index in a Group of Iranian Adolescents: Tehran Lipid and Glucose Study-2
Authors: Azizi Fereidoun , Allahverdian Sima , Mirmiran Parvin , Rahmani Maziar , Mohammadi Fatemeh
Published: January 2006

Objective: To study the prevalence of overweight and obesity in an adolescent population in Tehran and to determine possible association with energy and nutrient intake and distribution of energy over the day. Method: A cross-sectional study on 177 boys and 244 girls between 10–19 years old was performed. Overweight and obesity were defined by using recommended body mass index (BMI) cut-off values for adolescents. Total energy intake, percent of energy derived from protein, carbohydrate and fat and percent of energy supplied by each meal and snack were assessed by means of two 24-hour dietary recalls. Results: Prevalence of overweight and obesity was 10.7 and 5.1 in boys and 18.4 and 2.8 in girls, respectively. The composition of diet was not different between overweight/obese and normal weight subjects. BMI was related with breakfast energy percentage in girls (r = –0.18, p <0.01), with total energy intake in boys (r = 0.23, p <0.01), and with lunch energy percentage in both sexes. In boys (r = 0.16, p <0.05) and in girls (r= 0.22, p <0.01). Conclusion: High prevalence of overweight and obesity among adolescents was seen. In boys some relationship between total energy intake, distribution of energy over the day and BMI was seen. In girls BMI was only related with distribution of energy over the day.
Olive Oil and the Mediterranean Diet
Authors: Sanders T.A.B.
Published: January 2006

The high intake of olive oil in the Mediterranean diet contributes to the low intake of saturated fatty acids among populations in Southern Europe and is associated with a low incidence of coronary heart disease. Replacement of saturated fatty acids with oleic acid leads to a reduction in low-density lipoprotein (LDL) cholesterol without decreasing the concentration of high density lipoprotein (HDL) cholesterol. Oleic acid, however, may not be neutral with regards to its effects on risk of thrombosis which may have adverse consequences in populations with established atherosclerosis.
The Thiamine Status of Adult Humans Depends on Carbohydrate Intake
Authors: Elmadfa Ibrahim , Majchrzak Dorota , Rust Petra , Genser Dieter
Published: January 2006

Thiamine requirements for humans are generally expressed as absolute values per day (mg/d) or in relation to total caloric intake. Limited data are available on the relation between thiamine requirements and the intake of carbohydrates. This study was performed to investigate the influence of stepwise increases of carbohydrate intake on the status of thiamine in healthy volunteers under isocaloric conditions. During an adaptation phase of four days, the carbohydrate intake of twelve healthy volunteers (6 male, 6 female) was 55% of total energy intake. During the subsequent intervention periods, carbohydrate intake was increased to 65% of total energy for four days and to 75% for another four days. Thiamine intake, total energy intake, and physical activity were kept constant throughout the study. HPLC analysis was used to measure thiamine in plasma, urine and feces. Erythrocyte transketolase activity (ETK) was determined enzymatically. During the intervention periods thiamine decreased significantly (p < 0.05) in plasma (from 19.3 ± 3.3 to 16.4 ± 4.0 nmol/l) as well as in urine (from 72 ± 56 to 58 ± 21 mumol/mol creatinine). ETK and feces content of thiamine remained unchanged. An increase of dietary carbohydrate intake from 55% to 65% and 75%, respectively, of total caloric intake for four days per period at isocaloric conditions causes a decrease of plasma and urine levels of thiamine without affecting enzyme activities.
The alpha-linolenic Acid Content of Green Vegetables Commonly Available in Australia
Authors: Pereira Christine , Li Duo , Sinclair Andrew J.
Published: January 2006

Green vegetable consumption has long been considered to have health benefits mainly due to the vitamins, minerals and phytonutrients (such as vitamin C, folate, antioxidants etc) contained in a vegetable-rich diet. Additionally, green vegetables are known to contain a relatively high proportion of omega-3 polyunsaturated fatty acids (PUFAs), primarily in the form of alpha-linolenic acid (18:3n-3). However, there are no data available on the fatty acid composition and concentration of green vegetables commonly consumed in Australia. The present study determined the fatty acid content of 11 green vegetables that are commonly available in Australia. The total fatty acid concentrations of the vegetables under study ranged from 44 mg/100 g wet weight in Chinese cabbage to 372 mg/100 g in watercress. There were three PUFAs in all vegetables analyzed; these were 16:3n-3, 18:2n-6, and 18:3n-3 fatty acids. Sample vegetables contained significant quantities of 16:3n-3 and 18:3n-3, ranging from 23 to 225 mg/100g. Watercress and mint contained the highest amounts of 16:3n-3 and 18:3n-3, and parsley had the highest amount of 18:2n-6 in both percentage composition and concentration. Mint had the highest concentration of 18:3n-3 with a value of 195 mg/100 g, while watercress contained the highest concentration of 16:3n-3 at 45 mg/100 g. All 11 green vegetables contained a high proportion of PUFAs, ranging from 59 to 72% of total fatty acids. The omega-3 PUFA composition ranged from 40 to 62% of total fatty acids. Monounsaturated fatty acid composition was less than 6% of total fatty acids. The proportion of saturated fatty acids ranged from 21% in watercress and mint to 32% of total fatty acids in Brussels sprouts. No eicosapentaenoic and docosahexaenoic acids were detected in any of the samples. Consumption of green vegetables could contribute to 18:3n-3 PUFA intake, especially for vegetarian populations.
Maternal-Fetal N-6 and N-3 Polyunsaturated Fatty Acids Gradient in Plasma and Red Cell Phospholipids
Authors: Min Y. , Ghebremeskel K. , Crawford M. A. , Nam J. H. , Kim A. , Lee I. S. , Suzuki H.
Published: January 2006

Fatty acid distribution was investigated in ethnically and economically homogenous Korean mothers (n = 40) and neonates. Venous blood, maternal before delivery and cord, was obtained. Choline (CPG) and ethanolamine (EPG) phosphoglycerides and sphingomyelin (SM) were assayed. Mean arachidonic acid (AA) level was higher in plasma CPG and SM (p < 0.0001), and red cell CPG (p < 0.0001), EPG (p < 0.0001) and SM (p = 0.005) of the neonates. Similarly, the neonates had higher proportions of docosahexaenoic acid (DHA) in plasma CPG (p < 0.0001) and red cell CPG (p = 0.001) and EPG (p = 0.036). In contrast, linoleic and alpha-linolenic acids were significantly higher in maternal blood. Mead acid was elevated in plasma CPG (p < 0.0001) and red cell CPG and EPG (p < 0.0001) of the neonates. Consistent with data from high-fat-intake populations, our subjects, whose traditional diet is low in fat, exhibited maternal-fetal gradient in AA and DHA in plasma and red cell phospholipids. This may be due to an imbalance between supply and maternal and fetal requirements, and/or a physiological response to pregnancy. Prenatal nutritional constraint is associated with impaired development and a risk of chronic diseases in adults. AA and DHA are vital nutrients. Hence, there is a need to investigate whether the discrepancy between maternal and neonatal AA and DHA is a manifestation of nutritional insufficiency.
Effects of Androstenedione-Herbal Supplementation on Serum Sex Hormone Concentrations in 30- to 59-Year-old Men
Authors: Brown Gregory A. , Vukovich Matthew D. , Martini Emily R. , Kohut Marian L. , Franke Warren D. , Jackson David A. , King Douglas S.
Published: January 2006

The effectiveness of a nutritional supplement designed to enhance serum testosterone concentrations and prevent the formation of dihydrotestosterone and estrogens from the ingested androgens was investigated in healthy 30- to 59-year old men. Subjects were randomly assigned to consume DION (300 mg androstenedione, 150 mg dehydroepiandrosterone, 540 mg saw palmetto, 300 mg indole-3-carbinol, 625 mg chrysin, and 750 mg Tribulus terrestris per day; n = 28) or placebo (n = 27) for 28 days. Serum free testosterone, total testosterone, androstenedione, dihydrotestosterone, estradiol, prostate-specific antigen (PSA), and lipid concentrations were measured before and throughout the 4-week supplementation period. Serum concentrations of total testosterone and PSA were unchanged by supplementation. DION increased (p < 0.05) serum androstenedione (342%), free testosterone (38%), dihydrotestosterone (71%), and estradiol (103%) concentrations. Serum HDL-C concentrations were reduced by 5.0 mg/dL in DION (p < 0.05). Increases in serum free testosterone (r2 = 0.01), androstenedione (r2 = 0.01), dihydrotestosterone (r2 = 0.03), or estradiol (r2 = 0.07) concentrations in DION were not related to age. While the ingestion of androstenedione combined with herbal products increased serum free testosterone concentrations in older men, these herbal products did not prevent the conversion of ingested androstenedione to estradiol and dihydrotestosterone.
Plasma Protein Oxidation and Antioxidant Defense During Aging
Authors: Garibaldi Silvano , Valentini Sabina , Aragno Irene , Pronzato Maria Adelaide , Traverso Nicola , Odetti Patrizio
Published: January 2006

Background: Oxidative stress is an important process that occurs in vivo during aging and is considered one of the main causes of molecular damage to cellular and tissue structures. These changes can accumulate in biological structures during aging. Objective: The aim of this work is to evaluate plasma protein oxidative damage, measured as carbonyl groups content, and the concentration of some antioxidant molecules (vitamins and carotenoids) in 122 healthy volunteers (50 males and 72 females), 25 to 89 years old. Results: Total plasma proteins slightly decreased with age, but the level of carbonyl groups was similar in the adult (< 65 years) and in the old, and was similar in both sexes. Plasma concentration of antioxidant molecules such as a-tocopherol, b-carotene and other carotenoids, increased with age and correlated with the level of lipoproteins; plasma total cholesterol and triglycerides were significantly correlated with age as well. Conclusions: The surprisingly normal level of plasma protein carbonyl groups in our older subjects suggests two possibilities: a) the older people in our study are healthy and free from pathologies because of better protection against oxidative injury during their lifetimes, i.e., they maintained low-level oxidative damage on plasma proteins; or b) the level of carbonyl groups is normal because of the high turnover in plasma: the oxidized circulating proteins are preferentially and quickly removed; in this case oxidative damage is not discernible in plasma proteins but may proceed silently in other tissues.
Lycopene Supplementation Attenuates the Inflammatory Status of Colitis in a Rat Model
Authors: Reifen Ram , Nur Talia , Matas Zippora , Halpern Zamir
Published: January 2006

The aim of this study was to examine the influence of lycopene and beta-carotene on the inflammatory status in a rat model of induced-colitis. Using the 2,4,6-trinitrobenzenesulfonic acid (TNBS) model, colitis was induced in thirty-two male Wistar rats divided into four groups. Each group received a different diet regime in parallel with the induction of colitis and was sacrificed after seven days. The groups were divided as follows: Group A: without colitis and fed a normal chow diet; Group B: induced with colitis and fed a diet supplemented with lycopene (300 ug/rat/day); Group C: induced with colitis and fed a diet supplemented with beta-carotene (300 ug/rat/day); Group D: induced with colitis and fed a normal chow diet. Colonic inflammation following TNBS induction was characterized by hemorrhagic necrosis and fibrosis of the mucosa, increased colonic wall thickness, infiltration of inflammatory cells, and increased myeloperoxidase (MPO) activity. Supplementation of lycopene in the diet had a beneficial effect on the various macroscopic parameters examined including: colonic thickness, colon weight, and total area of inflammation. Furthermore, the level of myeloperoxidase (MPO) was significantly lower in the lycopene-treated group compared to the control group. In terms of microscopic changes, a more attenuated inflammatory reaction was observed in the group fed a diet supplemented with lycopene. No significant effect was noted in the beta-carotene-supplemented group. Therefore, we propose that the dietary supplementation of lycopene may be an effective approach for reducing the level of oxidative stress and improving the inflammatory status of colitis.
Glucosinolates: Bioavailability and Importance to Health
Authors: Johnson Ian. T.
Published: January 2006

Epidemiological studies suggest that brassica vegetables are protective against cancers of the lungs and alimentary tract. Cruciferous vegetables are the dietary source of glucosinolates, a large group of sulfur-containing glucosides. These compounds remain intact unless brought into contact with the enzyme myrosinase by pests, food processing, or chewing. Myrosinase releases glucose and breakdown products, including isothiocyanates. These highly reactive compounds are potent inducers of Phase II enzymes in vitro. Isothiocyanates also inhibit mitosis and stimulate apoptosis in human tumor cells, in vitro and in vivo. To understand and exploit such effects it is important to determine the routes of absorption of glucosinolate breakdown products, their metabolism, and delivery to systemic tissues. Glucosinolates can be gained or lost by vegetables during storage. They may be degraded or leached during processing, or preserved by thermal inactivation of myrosinase. Glucosinolates are broken down by plant myrosinase in the small intestine or by bacterial myrosinase in the colon. Isothiocyanates are absorbed from the small bowel and colon, and metabolites are detectable in human urine two to three hours after consumption of brassica vegetables. Interpretation of epidemiological data and exploitation of brassica vegetables for human health requires an understanding of glucosinolate chemistry and metabolism, across the whole food chain, from production and processing to the consumer.
Factors Influencing the Conversion of Carotenoids to Retinol: Bioavailability to Bioconversion to Bioefficacy
Authors: Tanumihardjo Sherry A.
Published: January 2006

Vitamin A (retinol) is a necessary nutrient for vision, reproduction, growth, and immune function. Pro-vitamin A carotenoids are an important source, especially in developing countries. While preformed vitamin A is readily available from foods, carotenoids are much more difficult to assimilate. A number of factors have been identified that either enhance or hinder the bioavailability of carotenoids. These have been presented in the literature and given the mnemonic SLAMENGHI by some researchers. The following factors are summarized: Species of carotenoid, molecular Linkage, Amount in the meal, Matrix properties, Effectors, Nutrient status, Genetics, Host specificity, and Interactions between factors. Identifying which of these are key issues for the general public, and promoting the increased consumption of fruits and vegetables with moderate and high levels of pro-vitamin A carotenoids, are important to vitamin A status and overall good health.
Influence of Lifestyle on Vitamin Bioavailability
Authors: van den Berg Henk , van der Gaag ( ) Martijn , Hendriks Henk
Published: January 2006

In this review the effects of lifestyle factors, especially alcohol consumption, on vitamin bioavailability are summarized and discussed. Alcohol effects are clearly dose-dependent. Excessive chronic alcohol intake is generally associated with vitamin deficiency (especially folate, thiamine, and vitamin B6) due to malnutrition, malabsorption, and ethanol toxicity. Effects of moderate alcohol use are mainly explained by a lower vitamin intake. In the case of vitamin A and beta-carotene, effects on post-absorptive (lipoprotein) metabolism have been demonstrated. In one diet-controlled crossover study, alcohol consumption resulted in an increase in the plasma vitamin B6 (PLP) content, especially after beer consumption (containing vitamin B6), but also after wine and spirit consumption (not containing vitamin B6). Smoking is also associated with a lower dietary vitamin intake. In the case of vitamin C, B12, folate, and beta-carotene, evidence has been presented for effects on postabsorptive metabolism, due to smoke-induced oxidative stress and/or vitamin inactivation. For vitamin E a direct effect of smoking on absorption has been demonstrated. There is no convincing evidence that low-fat diets negatively affect fat-soluble vitamin absorption, but cholesterol-lowering compounds (diets), or unabsorbable fat substitutes, may do so. Vitamin bioavailability may be compromised from certain vegetables (particularly raw), and/or from high-fiber foods, because of limited digestion and inefficient release of vitamins from the food matrix.
Cholesterol plus Methionine Feeding do not Induce Lipid Peroxidation and Atherosclerotic Changes in the Rat Aorta
Authors: Dogru-Abbasoglu Semra , Basaran-Küçükgergin Canan , Seçkin Sule , Öztezcan Serdar , Solakoglu Seyhun , Aykaç-Toker Gülçin , Uysal Müjdat
Published: January 2006

The purpose of this study was to investigate whether cholesterol plus methionine feeding may be a convenient model to produce atherosclerosis in rats, and also to examine the contribution of oxidative stress to this development. For this reason, lipid peroxide levels and antioxidant enzyme activities in the liver and aorta as well as histopathological findings were determined in male Wistar-albino rats fed a diet supplemented with cholesterol plus cholic acid and methionine for six months. This diet was found to increase lipid peroxide levels in the liver of rats. Hepatic glutathione peroxidase (GSH-Px) and catalase (CAT) activities increased, but superoxide dismutase (SOD) activity remained unchanged. In conclusion, cholesterol and methionine feeding in rats did not cause oxidative stress and atherosclerotic changes in the aorta, although hepatic prooxidant-antioxidant balance was affected by this diet.
Administration of beta-carotene Suppresses Lipid Peroxidation in Tissues and Improves the Glucose Tolerance Ability of Streptozotocin-Induced Diabetic Rats
Authors: Furusho Tadasu , Kataoka Eiko , Yasuhara Tadashi , Wada Masahiro , Innami Satoshi
Published: January 2006

The present study attempted to examine the antioxidative effect of dietary beta-carotene (BC) on lipid peroxidation (LPO) in the streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley (SD) rats were fed on the AIN76 standard diet with or without 0.1% BC. On the 21st day after introduction of these diets, STZ was intraperitoneally injected in half the subjects of both groups. All animals were sacrificed seven days after the STZ injection.Glucose tolerance and thiobarbituric acid reactive substance (TBARS) in the tissues or serum were measured. Body weight gain in the BC + STZ group was significantly higher than that in the STZ group (p < 0.05). Blood glucose and TBARS concentrations of the liver, pancreas, and serum in the BC + STZ group were significantly lower than those in the STZ group. The blood insulin concentration in the BC + STZ group was significantly higher than that in the STZ group. The hepatic and serum beta-carotene concentrations in the BC + STZ group were significantly lower than those in the BC group. Moreover, the synthesis and oxidation of glutathione (GSH) in the BC + STZ group were reduced when compared to the STZ group. These results suggest that the administration of beta-carotene suppresses the elevation of LPO and reduces the symptoms of diabetes mellitus (DM) in the STZ-induced diabetic rats.
Study on the Interaction of Ions of Transient Metals with Ascorbic Acid in the Presence of Different Scavengers of Active Oxygen Species in SOS Chromotes
Authors: Marczewska Jadwiga , Koziorowska Jadwiga H.
Published: January 2006

SOS chromotest was employed to study the interaction of ascorbic acid with free ions of transient metals in the presence of added catalase, superoxide dismutase or D-mannitol. Catalase diminished the genotoxic activity of the mixture of ascorbic acid with copper ions in E. coli strains PQ37 and PQ 300, but genotoxicity of this mixture was not suppressed by superoxide dismutase and D-mannitol. The results suggest that copper ions diminished the content of peroxide generated by ascorbic acid.
Effects of Vitamin C and Vitamin E on Lipid Peroxidation Status, Serum Hormone, Metabolite, and Mineral Concentrations of Japanese Quails Reared under Heat Stress (34º C)
Authors: Sahin Kazim , Kucuk Osman , Sahin Nurhan , Sari Mustafa
Published: January 2006

This study was conducted to determine the effects of dietary vitamin C (L-ascorbic acid) and vitamin E (a-tocopherol acetate) on lipid peroxidation status measured as MDA and serum triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), as well as some other serum metabolite and mineral concentrations of Japanese quails reared under heat stress (34º C). One hundred-eighty 10-day-old Japanese quails were randomly assigned to six treatment groups, three replicates of 10 birds each. Using a 2 × 3 factorial design, the birds received two levels of vitamin C (100 and 200 mg/kg of diet) or three levels of vitamin E (125, 250, or 500 mg/kg of diet). Greater dietary vitamin E and vitamin C resulted in a greater serum T3, T4, and TSH (p=0.001), but lower ACTH (p=0.001) concentrations. Serum concentrations of T4 and TSH increased to a greater extent by increasing dietary vitamin C when greater vitamin E levels were fed (interaction, p=0.001). Serum glucose, urea, triglycerides, and cholesterol concentrations decreased (p=0.001), while protein and albumin concentrations increased (p =0.001) when both dietary vitamin C and vitamin E were increased. Serum activities of SGOT and SGPT were not influenced by dietary vitamin C or vitamin E (p>0.43). However, serum activity of AP increased (p=0.001) by increasing both dietary vitamin C and vitamin E. Increasing both dietary vitamin C and vitamin E caused an increase in serum concentrations of Ca, P, K (p=0.001), Fe, and Zn (p=0.01) but a decrease in serum concentrations of Na (p=0.001) and Cu (p=0.01). Interactions between vitamin C and vitamin E were detected for Ca, P, Na, and K (p =0.001). Greater dietary vitamin C and vitamin E resulted in a greater serum and liver vitamin E, C, and A (p_0.05), but lower MDA (p=0.001) concentrations. Results of the present study conclude that supplementing a combination of dietary vitamin C (200 mg) and vitamin E (250–500 mg) offers a good management practice to reduce heat stress-related decreases in performance of Japanese quails.
Vitamin A Intake is Low Among Pregnant Women in Central Java, Indonesia
Authors: Persson Viveka , Hartini Ninuk , Greiner Ted , Hakimi Mohammed , Stenlund Hans , Winkvist Anna
Published: January 2006

From 1996–1998, a longitudinal study on nutritional status during pregnancy was carried out in Purworejo District, Central Java, Indonesia. Dietary intake was assessed in each trimester using six 24-hour recalls, and analyzed cross-sectionally among 493 women. The proportion of women below the Indonesian RDI for vitamin A (700 RE) ranged from 83% in the first trimester to 76% in the third. Regardless of total vitamin A intake, plant sources contributed 64–79% in all three trimesters. The contribution from animal and fortified sources was generally lower throughout pregnancy for those with low education compared to those with high education. Significant risk factors for having a low vitamin A intake (< FAO/WHO basal RDI, 370 RE) in the second and third trimesters were fewer than six years of education, low socio-economic status, a low energy intake, and a low vitamin A intake in the previous trimester. Home gardening and chicken-raising were not positively associated with vitamin A intakes. Given the large percentage of women with inadequate vitamin A intakes, further strategies are needed to increase the vitamin A intake of all pregnant women in this area.
Tocopherols Enhance Neurogenesis in Dentate Gyrus of Adult Rats
Authors: Cuppini Riccardo , Ciaroni Sandra , Cecchini Tiziana , Ambrogini Patrizia , Ferri Paola , Cuppini Carla , Ninfali Paolino , Del Grande Paolo
Published: January 2006

In the dentate gyrus of the mammalian hippocampus, neurogenesis carries on throughout postnatal life. The aim of this work was to identify an exogenous control factor of adult neurogenesis. Neurogenesis in the adult dentate gyrus was previously found to be enhanced in vitamin E-deficient rats. The effects of alpha- or beta-tocopherol supplementation on neurogenesis in the adult dentate gyrus were investigated by 5-bromo-2’-deoxyuridine labeling. Tocopherol was found to increase the survival of newborn cells and the total number of granule cells in the adult rat dentate gyrus. Newborn cells were phenotypically characterized by expression of the immature neuron marker TOAD-64 (turned on after division-64). Therefore tocopherol in high doses possibly increases the number of granule cells in the dentate gyrus by saving newborn cells from death.
Vitamin A Metabolism is Altered in Brown Norway and Long-Evans Rats Infused with Naftidrofuryl or Erythromycin Intravenously
Authors: Schindler Rainer , Fielenbach Tanja , Rave Gerhard , Blömer Anne , Kellersmann Richard
Published: January 2006

Enzymatic retinyl ester hydrolysis is a key reaction for maintaining cellular retinol homeostasis. The ability of naftidrofuryl and erythromycin to inhibit retinol liberation by retinyl ester hydrolase (REH) in vitro suggests an ability to interfere with vitamin A metabolism in vivo, particularly during hepatic processing. To address this question, systemic and local response to these agents were studied in Brown Norway (BN) and Long-Evans (LE) rats. The study was conducted in two parts: a drug-loading phase and a washout phase. Analysis of variance of the time course changes in plasma retinol during the post-treatment period (Days 10–18) showed rat strain (p < 0.04) and time (p < 0.001; strain-by-time interactive effect, p < 0.001) to be significant factors, but drug exposure (p = 0.19) was not significant. Endpoints included hepatic REH activity, size and composition of the liver vitamin A stores, and retinoid content of the kidneys. Rats recovering from naftidrofuryl dosing demonstrated a lower REH activity than did animals recovering from erythromycin treatment (p < 0.009). The major side effect of erythromycin is vitamin A accumulation in the liver (p < 0.001) and reductions in retinol reserves (p < 0.02) were among the consequences of naftidrofuryl treatment. In the kidney of LE rats, there were higher concentrations of vitamin A (p < 0.003) secondary to naftidrofuryl exposure. Together our data suggest that clinically achievable concentrations of the drugs, given as a continuous infusion, produce aberrations in vitamin A metabolism.
Serum Retinol of Chadian Nomadic Pastoralist Women in Relation to their Livestocks’ Milk Retinol and beta-Carotene Content
Authors: Zinsstag Jakob , Schelling Esther , Daoud Saada , Schierle Josef , Hofmann Peter , Diguimbaye Colette , Daugla Doumagoum Moto , Ndoutamia Guelmbaye , Knopf Lea , Vounatsou Penelope , Tanner Marcel
Published: January 2006

Human serum retinol and livestock milk retinol levels were assessed as part of a study on the health status of Chadian nomadic pastoralists and their livestock in close partnership between Chadian public health and livestock institutions. Of the examined women (n = 99), 43% were moderately retinol-deficient (0.35 mol/L < × < 0.7 mol/L 95% CI; 33–54%), and 17% severely retinol-deficient (< 0.35 mol/L 95% CI; 10–26 %). None of the interviewed women (n = 87) reported the consumption of fruit, and only two of fresh vegetables were reported consumed in the past 24 hours. Milk is the almost exclusive source of vitamin A for these populations. Goats (n = 6) had the highest average milk retinol level (329 ± 84 mug/kg [mean ± SEM]), followed by cattle (n = 25; 247 ± 32 mug/kg), and camels (n = 12; 120 ± 18 mug/kg). Milk retinol levels did not differ between the rainy and dry seasons. Human serum retinol depends significantly on livestock milk retinol levels (partial slope 0.23; 95% CI: 0.008–0.47). Our study supports the use of goat and cow milk as an important source of vitamin A in pastoral nomadic settings. However, the levels still require to be complemented further by promoting green leafy vegetables, fruits, and supplements.
Differences in the Accumulation of Ascorbic Acid in Normal, Myeloperoxidase Deficient and NADPH-Oxidase Deficient Granulocytes
Authors: Gerber Claudia , Niethammer Dietrich , Bruchelt Gernot
Published: January 2006

Granulocytes contain large quantities of ascorbic acid (AA). The uptake mechanism is mainly restricted to the accumulation of the oxidized form, dehydroascorbate (DHA). We investigated the uptake of ascorbic acid and dehydroascorbate of normal, myeloperoxidase (MPO)-deficient, and NADPH-oxidase-deficient granulocytes. The accumulation of ascorbic acid was increased in all types of granulocytes after stimulation with phorbol-myristate-acetate, whereas the NADPH-oxidase-deficient cells showed a decreased uptake compared to normal and MPO-deficient cells. The intracellular concentration of ascorbic acid was further enhanced after incubation of granulocytes with DHA, most prominently in NADPH-oxidase-deficient granulocytes. MPO-deficient granulocytes are not able to produce HOCl after activation. The granulocytes of one individual with total MPO deficiency accumulated ascorbate in higher concentrations than did cells with partial MPO deficiency, indicating that HOCl is of minor importance for the oxidation of ascorbate. Since the ability of MPO-deficient cells to kill microorganisms is pronounced in contrast to NADPH-oxidase-deficient cells, effective mechanisms of compensating for the absence of HOCl must exist. We hypothesize that the enhanced uptake of ascorbic acid combined with an enhanced superoxide anion production may favor the generation of OH radicals via the Fenton reaction.
Carotenoids, Mostly the Xanthophylls, Exchange Between Plasma Lipoproteins
Authors: Tyssandier Viviane , Choubert Georges , Grolier Pascal , Borel Patrick
Published: January 2006

Carotenoids are exclusively transported by lipoproteins; in vitro studies suggest that they might protect these particles against oxidation. Little is known about the factors that govern the distribution of these micronutrients among lipoproteins. The objective of this study was to assess whether carotenoids are exchanged between lipoproteins and what factors, if any, were involved. In the first experiment, different groups of trout were fed for five days with either a carotenoid-free diet or with diets containing 80 mg pure carotenoid per kilogram of feed. Lipoproteins were separated by ultracentrifugation and carotenoid-rich, high-density lipoproteins (HDL) were incubated for two hours at 37°C with carotenoid-free, very low-density lipoproteins (VLDL), and vice versa. After incubation, lipoproteins were re-separated and carotenoids were quantified to measure the transfer. The same experiments were done in the presence of cholesteryl ester transfer protein (CETP) and lecithin cholesterol acyltransferase (LCAT) inhibitors. In a second experiment, the exchange was measured between human VLDL and HDL. In trout, incubation of carotenoid-rich HDL with carotenoid-free VLDL resulted in the appearance of carotenoids in VLDL, and inversely. The higher the hydrophobicity of a carotenoid, the lower its proportion in HDL after incubation. CETP and LCAT inhibitors significantly increased the proportion of carotenoids in HDL after incubation. Results obtained with human lipoproteins showed that the xanthophyll lutein transferred between lipoproteins, but could not show any carotenes (alpha-carotene, beta-carotene, and lycopene) transfer. We conclude that carotenoids, chiefly the xanthophylls, exchange between lipoproteins. The transfer depends on plasma factor(s) sensitive to CETP and/or LCAT inhibitors.
Vitamin E can Reduce Blood Pressure in Mild Hypertensives
Authors: Boshtam Maryam , Rafiei Morteza , Sadeghi Kamran , Sarraf-Zadegan Nizal
Published: January 2006

This triple-blind placebo-controlled clinical trial was performed to determine the effects of the antioxidant vitamin E on blood pressure and heart rate in patients with mild hypertension. A total of 70 new mild hypertensive subjects (systolic blood pressure, SBP: 140–160 mmHg; diastolic blood pressure, DBP: 90–100 mmHg) without secondary hypertension were selected from among people referred to the Hypertension Unit of Isfahan Cardiovascular Research Center and divided randomly into two groups of drug (DG) and placebo (PG). All subjects were aged from 20 to 60 years old, without any other cardiovascular risk factors. The drug group received vitamin E tablets (200 IU/day) and the placebo group received placebo only for 27 weeks. At the beginning and the end of the study, the blood vitamin E level was measured fluorimetrically in all subjects according to the Hansen and Warwick method [14, 15]. Blood pressure and heart rate were measured at the beginning, during, and at the end of the study. Blood pressure was measured by a physician using one random zero mercury sphygmomanometer. Personal information and dietary habits of subjects were collected by separate questionnaire. At the end of the study, it was found that the vitamin E supplement had caused a remarkable decrease in SBP (–24% in DG versus –1.6% in PG) and a less remarkable decrease in DBP (–12.5% in DG versus –6.2% in PG) (p < 0.05). The change in heart rate was –4.3% in DG, and –14.0% in PG (p < 0.05). It is concluded that a vitamin E supplement of 200 IU/day can be effective in mild hypertensive patients in the long term, probably due to nitric oxide, and improve their blood pressure status. Therefore, vitamin E supplement could be recommended to such patients.
Increased Lipid Peroxidation in Serum and Low-Density Lipoproteins Associated with Aging in Humans
Authors: Balkan Jale , Kanbagli Öznur , Mehmetçik Güldal , Mutlu-Türkoglu Ümit , Aykaç-Toker Gülçin , Uysal Müjdat
Published: January 2006

This study was carried out in 140 healthy subjects who were divided into three subgroups of age: young (21–40 years), mature (41–60 years), and elderly ( 61–85 years) to investigate lipid peroxides and the antioxidant system in serum and low-density lipoproteins (LDL). Serum levels of cholesterol and LDL-cholesterol increased with age. The elderly group was found to have higher polyunsaturated fatty acid (PUFA) levels, thiobarbituric acid reactive substances (TBARS), diene conjugates, and lower cholesterol-adjusted vitamin E levels and antioxidant activity (AOA) as compared to the young group. No age-related difference was detected in serum vitamin C levels. Age correlated positively with serum cholesterol, LDL-cholesterol, PUFA, TBARS, diene conjugates, and negatively with cholesterol-adjusted vitamin E levels and AOA. In addition, endogenous LDL diene conjugate levels and the susceptibility of LDL to copper-induced lipid peroxidation increased in elderly subjects as compared with young subjects. In addition, positive correlations were detected between age and LDL endogenous diene conjugate levels and TBARS formation after copper incubation. However, the susceptibility of whole serum to copper-induced lipid peroxidation did not change in young and elderly subjects. Our results show that endogenous lipid peroxide levels in serum and LDL, and the susceptibility of LDL to copper-induced oxidation, increased with aging in humans.
Ascorbic Acid Content of Blood Plasma, Erythrocytes, Leukocytes and Liver in Camels (Camelus dromedarius) without or with Parasite Infections
Authors: Mohamed  , Beynen
Published: January 2006

Healthy camels (Camelus dromedaris) and those naturally infected with trypanosomiasis, sarcoptic mange, and helminthiasis were compared as to ascorbic acid (vitamin C) contents of red blood cells, white blood cells, whole blood, plasma, and liver. The camels were kept under natural grazing conditions in Sudan. Reduced levels of vitamin C were found in camels with parasite infections, especially in animals with trypanosomiasis. It is suggested that the low vitamin C status in infected camels is caused by increased utilization and/or decreased synthesis of vitamin C.
Seasonal Variation of Food Consumption and Selected Nutrient Intake in Linxian, a High Risk Area for Esophageal Cancer in China
Authors: Zou Xiao Nong , Taylor Philip , Mark Steven , Chao Ann , Wang Wen , Dawsey Sanford , Wu Yan Ping , Qiao You Lin , Zheng Su Fang
Published: January 2006

Linxian, China, is a region with high incidence of esophageal cancer and a history of poor nutritional status. Nutrition Intervention Trials were conducted in this area from 1985 through 1991 and found a reduction in total cancer mortality in the group receiving supplementation of beta-carotene/selenium/alpha-tocopherol. The positive results of those trials have, in part, been ascribed to the poor nutritional status of this population. To investigate more recent food patterns, nutrient intakes, and seasonal variations in the diet, dietary surveys were conducted among the residents of Linxian in 1996. Food consumption data were collected among 104 households in spring and 106 households in autumn using a method of food inventory changes. Intake of nutrients was estimated and compared to the Chinese Recommended Dietary Allowance (RDA). In both seasons, the five most common food groups consumed were cereals, fresh vegetables, yams, seasonings, and eggs. Low nutrient intakes were found for selenium (79% RDA and 66% RDA), zinc (72% RDA and 62% RDA), vitamin B2 (64% RDA and 52% RDA), and calcium (53% RDA and 39% RDA) in both spring and autumn. A large seasonal variation was seen in the consumption of leafy vegetables, root vegetables and eggs, all of which might have contributed to the lower intake of vitamin A (25% RDA), vitamin C (75% RDA), protein (76% RDA), and vitamin E (78% RDA) in autumn. These indicate that the nutrient intake in Linxian is inadequate for a number of vitamins and minerals including those shown to be associated with esophageal cancer.
Ascorbic Acid does not Improve Endothelium-Dependent Flow-mediated Dilatation of the Brachial Artery in Patients with Raynaud’s Phenomenon Secondary to Systemic Sclerosis
Authors: Mavrikakis M. E. , Lekakis J. P. , Papamichael M. , Stamatelopoulos K. S. , Kostopoulos Ch. C. , Stamatelopoulos S. F.
Published: January 2006

Previous studies have shown that patients with Raynaud’s phenomenon secondary to systemic sclerosis present abnormal endothelial function; the mechanisms responsible for the endothelial dysfunction are unknown but increased vascular oxidative stress could be a possible cause. The hypothesis that a potent water-soluble antioxidant can reverse endothelial dysfunction in these patients was tested in the present study. We examined 11 female patients with Raynaud’s phenomenon secondary to systemic sclerosis and ten healthy control women by ultrasound imaging of the brachial artery to assess flow-mediated (endothelium-dependent) and nitrate-induced (endothelium-independent) vasodilatation. Flow-mediated dilatation and nitrate-induced dilatation were significantly reduced in patients with Raynaud’s phenomenon, indicating abnormal endothelial and smooth muscle cell function. Patients with Raynaud’s phenomenon entered a double-blind, randomized, crossover placebo-controlled trial and received orally 2 g of ascorbic acid or placebo; vascular studies were repeated two hours after ascorbic acid or placebo administration. Flow-mediated dilatation did not improve after ascorbic acid (1.6 ± 2.2% to 2.2 ± 2.5%, ns) or placebo administration (1.2 ± 1,9% to 1.7 ± 1.4%, ns); also nitrate-induced dilatation was similar after ascorbic acid or placebo (16 ± 7.4% vs 17 ± 8%, ns), suggesting no effect of ascorbic acid on endothelial and vascular smooth muscle function. In conclusion, ascorbic acid does not reverse endothelial vasomotor dysfunction in the brachial circulation of patients with Raynaud’s phenomenon secondary to systemic sclerosis. The use of different antioxidants or different dosing of ascorbic acid may be required to show a beneficial effect on endothelial vasodilator function.
Body Composition Assessed by Anthropometry and Bioelectric Impedance Analysis in Older Persons Recovering from Cerebrovascular Accident
Authors: Sotillo C. , López-Jurado M. , Encarnación M. , Mataix J. , Llopis J.
Published: January 2006

We investigated body composition in older patients who had experienced a cerebrovascular accident (CVA) and were participating in a recovery program that included physical exercise. We studied 61 persons in two groups. One group consisted of 13 men and 12 women (mean age, 68 years) who were receiving day center care to recover from a CVA that had occurred from six months to one year previously. The second group (control) consisted of 20 men and 16 women (mean age, 68 years) in good health, residing in a retirement home. Most subjects in both groups were able to perform normal activities of daily living without help and showed a high degree of independence (> 60 on the Barthel scale). Bioelectric impedance and anthropometric methods were used to measure the magnitude of changes in fat-free mass and fat mass. Percentage total body fat measured with bioelectric impedance was higher in both groups than when measured anthropometrically. The anthropometric values and bioelectric impedance results in patients who participated in a physical exercise program were similar to the findings in control subjects. The anticipated loss in muscle mass and gain in body fat as a result of inactivity associated with illness was not seen, possibly because of the personalized program of continuous physical exercise. Our comparison of older people recovering from CVA and apparently healthy older people illustrates the benefits of physical exercise in compensating for changes in body composition as a result of immobility during convalescence.
Cholesterol-Lowering Properties of Amaranth Grain and Oil in Hamsters
Authors: Berger A. , Gremaud G. , Baumgartner M. , Rein D. , Monnard I. , Kratky E. , Geiger W. , Burri J. , Dionisi F. , Allan M. , Lambelet P.
Published: January 2006

Amaranth was an important ancient grain and has current nutritional potential, being high in protein, fiber, lysine, magnesium, calcium, and squalene. Limited, inconsistent evidence demonstrates amaranth grain or oil can lower cholesterol in animal models. In the present study, hamsters received hypercholesterolemic diets consisting of a control, 10 or 20% Amaranthus cruentus grain, or 2.5 or 5% crude amaranth oil for four weeks. Amaranth oil (5%) decreased total and non-high-density lipoprotein (HDL) cholesterol by 15 and 22%, respectively, compared to control. Amaranth grain (20%; providing 1.4% amaranth oil) lowered non-HDL cholesterol and raised HDL cholesterol. Amaranth grain and oil decreased very low-density lipoprotein (VLDL) cholesterol by 21–50%; and increased fecal excretion of particular neutral sterols and the bile acid ursodeoxycholate. Amaranth oil (5%) additionally increased the cholesterol synthesis rate, possibly due to compensatory mechanisms; and decreased hepatic cholesterol ester, indicating reduced cholesterol ester availability for VLDL secretion and consistency with reduced VLDL cholesterol. Amaranth thus affected absorption of cholesterol and bile acids, cholesterol lipoprotein distribution, hepatic cholesterol content, and cholesterol biosynthesis. Amaranth grain and oil did not affect these pathways identically.
Potential Risks and Benefits of Phytoestrogen-Rich Diets
Authors: Cassidy
Published: January 2006

Interest in the physiological role of bioactive compounds present in plants has increased dramatically over the last decade. Of particular interest in relation to human health are the class of compounds known as the phytoestrogens, which embody several groups of non-steroidal oestrogens including isoflavones & lignans that are widely distributed within the plant kingdom. Data from animal and in vitro studies provide plausible mechanisms to explain how phytoestrogens may influence hormone dependent states, but although the clinical application of diets rich in these oestrogen mimics is in its infancy, data from preliminary studies suggest potential beneficial effects of importance to health. Phytoestrogens are strikingly similar in chemical structure to the mammalian oestrogen, oestradiol, and bind to oestrogen receptors (ER) with a preference for the more recently described ERb. This suggests that these compounds may exert tissue specific effects. Numerous other biological effects independent of the ER (e.g. antioxidant capacity, antiproliferative and antiangiogenic effects) have been ascribed to these compounds. Whether phytoestrogens have any biological activity in humans, either hormonal or non hormonal is a contentious issue and there is currently a paucity of data on human exposure. Much of the available data on the absorption and metabolism of dietary phytoestrogens is of a qualitative nature; it is known that dietary phytoestrogens are metabolised by intestinal bacteria, absorbed, conjugated in the liver, circulated in plasma and excreted in urine. Recent studies have addressed quantitatively what happens to isoflavones following ingestion – with pure compound and stable isotope data to compliment recent pharmacokinetic data for soy foods. The limited studies conducted so far in humans clearly confirm that soya isoflavones can exert hormonal effects. These effects may be of benefit in the prevention of many of the common diseases observed in Western populations (such as breast cancer, prostate cancer, menopausal symptoms, osteoporosis) where the diet is typically devoid of these biologically active naturally occurring compounds. However since biological effects are dependent on many factors including dose, duration of use, protein binding affinity, individual metabolism and intrinsic oestrogenic state, further clinical studies are necessary to determine the potential health effects of these compounds in specific population groups. However we currently know little about age related differences in exposure to these compounds and there are few guidelines on optimal dose for specific health outcomes.
Non-Nutritive Bioactive Constituents of Plants: Dietary Sources and Health Benefits of Glucosinolates
Authors: Lund
Published: January 2006

A high intake of cruciferous vegetables is associated with a reduced risk of cancer, particularly lung and those of the gastrointestinal tract. This protective effect has been linked to the presence of glucosinolates in these vegetables. Certain metabolites of the glucosinolates, particularly the isothiocyanates and nitriles have been shown to both modify xenobiotic metabolising enzymes and induce cell cycle arrest and apoptosis. Different metabolites are more or less effective in mediating each response depending on the model system employed. It is likely that a combination of these responses explains the chemo-preventive characteristics of Brassicas and that a combination of different cruciferous vegetables will provide optimal protection.