Increased selenium intake in elderly high fish consumers may account for health benefits previously ascribed to omega-3 fatty acids.

OBJECTIVE: To examine relationships between fish consumption and plasma selenium (Se) and red blood-cell fatty acid (RBC FA) profile in aged subjects. We hypothesised that the importance of Se has been underestimated when interpreting the beneficial effect of fish consumption on health. DESIGN: Cross-sectional analysis of data from a prospective cohort study. SETTING: The EVA study in Nantes, France (1991-2002). SUBJECTS: 200 subjects aged > or = 69 y with information on RBC FAs, plasma Se and completed food frequency questionnaires. METHODS: We examined correlations between the most abundant FAs, Se and number of fish meals per week. Linear regression models were used. RESULTS: Plasma Se was negatively correlated with RBC omega6 poly-unsaturated FA (PUFAs) and positively with omega3 PUFAs. Plasma Se, RBC omega3 PUFAs, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) increased with fish consumption. Conversely, levels of omega6 PUFAs were lower in the highest fish consumption group. All associations between plasma Se and fish consumption remained significant when adjusting for omega6 PUFAs alone or additionally for age, sex, education, diabetes, hypertension, dyslipidemia, cardiovascular diseases, and broad food categories (meat, eggs, dairy products, cereals, fruit and vegetable). Associations between omega3 PUFAs and fish also remained significant in the same model independently of Se. In linear regression models adjusted for demographic indicators, fish consumption explained only 2.6% of the variance in RBC omega3 FAs (6.2% for omega6) but as much as 15% of the variance in plasma selenium. CONCLUSIONS: The observed health benefits of fish consumption in the elderly could be related not only to the increase in omega3 FA intake but also to other nutrients such as selenium. It is important to consider this observation when interpreting associations between fish consumption and health status in the elderly, particularly with regard to brain function.

Effects of a combined micronutrient supplementation on maternal biological status and newborn anthropometrics measurements: a randomized double-blind, placebo-controlled trial in apparently healthy pregnant women.

OBJECTIVE: To investigate the possible beneficial effects of a micronutrient supplementation to apparently healthy pregnant women on maternal biological status and new born anthropometric characteristics. SETTING: Departments of Obstetric of the University Hospital of Grenoble (France) and Lyon (France), Laboratoire of Biology of Oxidative Stress, UFR de Pharmacie. Grenoble (France). STUDY DESIGN: Double-blind, randomized placebo-controlled intervention trial. SUBJECTS: A total of 100 apparently healthy pregnant women were recruited at 14+/-2 weeks of gestation to delivery. At the end, they were 65 women to follow out the study. INTERVENTIONS: Daily consumption over gestation of a micronutrients supplement or placebo. MAIN OUTCOME MEASURES: Plasma micronutrient levels and oxidative stress parameters were measured in mothers at 14 and 38 weeks of gestation. New born's anthropometric characteristics were measured at delivery. RESULTS: In the supplemented group, folic acid, vitamin C, E, B2, B6 and beta-carotene levels were higher than in the placebo group. Oxidative stress parameters were not different between the groups. Birth weights were increased by 10% and the number of low newborn weights (<2700 g) decreased significantly when the mother received the supplementation. Maternal plasma Zn levels were positively correlated to the newborn heights. CONCLUSION: A regular intake of a micronutrient supplement at nutritional dose may be sufficient to improve micronutrient status of apparently healthy pregnant women and could prevent low birth weight of newborn.

Five year changes in mental health and associations with vitamin B12/folate status of elderly Europeans.

OBJECTIVE: To describe 5-year changes of mental health in SENECA participants, and to examine whether mental health is associated with the status of vitamin B12 and folate. DESIGN: A longitudinal, multicentre study including a Baseline study, a Follow-up study, and a Finale study. SUBJECTS: Inhabitants of 11 European towns, born between 1913 and 1918, were randomly selected at baseline to participate in the SENECA study. Of the 1099 enrolled subjects in the Follow-up study, 586 participated in the Finale study. INTERVENTION: Mental health status was assessed by the Mini-Mental State Examination (MMSE, cognitive impairment defined as MMSE<23) and the 15-item Geriatric Depression Scale (GDS, depression defined as GDS>5). RESULTS: In the Finale study, mean overall MMSE score was 26.1 for men and 25.6 for women, while mean overall GDS score was 3.1 for men and 4.1 for women. Among subjects that participated in both the Follow-up and the Finale study, MMSE scores decreased with 0.9 points (P<0.0001) and 1.0 points (P<0.0001) among men and women respectively. The GDS scores decreased with 0.7 points (P<0.0001) for men and 0.8 points (P<0.0001) for women. Among subjects that participated in the Finale study, no significant correlations have been observed between mental health and vitamin B12/folate status. CONCLUSION: In the Finale study, mental health of the majority of the SENECA participants remained intact. In contrast to the Follow-up study, no associations between mental health and vitamin B12/folate status were emerged.

No significant effects of lutein, lycopene or beta-carotene supplementation on biological markers of oxidative stress and LDL oxidizability in healthy adult subjects.

OBJECTIVE: The objective of this study was to determine the effect of individual carotenoid supplementation on biochemical indices of oxidative status in apparently healthy adult males. METHODS: The study was a placebo controlled single blind study. Healthy male volunteers (n= 175) were assigned to four groups. They received daily supplements of beta-carotene (15 mg), lutein (15 mg), lycopene (15 mg) and placebo for three months. The effects of the supplementation on antioxidant status were monitored by plasma carotenoid, vitamin C and A levels, glutathione (GSH and GSSG) concentrations, protein SH groups. erythrocyte antioxidant enzyme activities (Cu-Zn SOD, Se-GSH-Px) and susceptibility of LDL to copper-induced oxidation. RESULTS: beta-carotene, lycopene and lutein supplementation led to significant plasma and LDL increases in each of these carotenoids, without modifications of other carotenoid levels in plasma or in LDL. The supplementation failed to enhance the resistance of LDL to oxidation or to modify the LDL polyunsaturated/ saturated fatty acid ratio. Vitamin C, GSH, protein SH groups and antioxidant metalloenzyme activities were also unchanged. CONCLUSION: We did not observe beneficial or adverse effects of lutein, lycopene or beta-carotene supplementation on biomarkers of oxidative stress. In apparently healthy subjects, carotenoid supplementation does not lead to significantly measurable improvement in antioxidant defenses.

A European carotenoid database to assess carotenoid intakes and its use in a five-country comparative study.

A food frequency questionnaire (FFQ) and carotenoid database with information on alpha- and beta-carotene, lutein, lycopene and beta-cryptoxanthin was prepared and used to compare the carotenoid intakes in five European countries: UK, Republic of Ireland, Spain, France and The Netherlands. Eighty, age- (25-45 years) and sex-matched volunteers were recruited in each of the five countries. A FFQ and carotenoid database was prepared of the most commonly consumed carotenoid rich foods in the participating countries and the information was used to calculate frequency and intake of carotenoid-rich foods. The median total carotenoid intake based on the sum of the five carotenoids, was significantly higher (P < 0.05) in France (16.1 mg/day) and lower in Spain (9.5 mg/day,) than the other countries, where the average intake was approximately 14 mg/day. Comparison of dietary source of carotenoids showed that carrots were the major source of beta-carotene in all countries except Spain where spinach was most important. Likewise, carrots were also the main source of alpha-carotene. Tomato or tomato products, were the major source of lycopene. Lutein was mainly obtained from peas in Republic of Ireland and the UK, however, spinach was found to be the major source in other countries. In all countries, beta-cryptoxanthin was primarily obtained from citrus fruit. Comparing the data with that from specific European country studies suggests that the FFQ and carotenoid database described in the present paper can be used for comparative dietary intake studies within Europe. The results show that within Europe there are differences in the specific intake of some carotenoids which are related to different foods consumed by people in different countries.

Increased lipid peroxidation in pregnant women after iron and vitamin C supplementation.

Iron overload could promote the generation of free radicals and result in deleterious cellular damages. A physiological increase of oxidative stress has been observed in pregnancy. A routine iron supplement, especially a combined iron and vitamin C supplementation, without biological justifications (low hemoglobin [Hb] and iron stores) could therefore aggravate this oxidative risk. We investigated the effect of a daily combined iron supplementation (100 mg/d as fumarate) and vitamin C (500 mg/d as ascorbate) for the third trimester of pregnancy on lipid peroxidation (plasma TBARS), antioxidant micronutriments (Zn, Se, retinol, vitamin E, (beta-carotene) and antioxidant metalloenzymes (RBC Cu-Zn SOD and Se-GPX). The iron-supplemented group (n = 27) was compared to a control group (n = 27), age and number of pregnancies matched. At delivery, all the women exhibited normal Hb and ferritin values. In the supplemented group, plasma iron level was higher than in the control group (26.90 +/- 5.52 mmol/L) and TBARs plasma levels were significantly enhanced (p < 0.05) (3.62 +/- 0.36 vs 3.01 +/- 0.37 mmol/L). No significant changes were observed in plasma trace elements and red blood cell antioxidant metalloenzymes. Furthermore, the alpha-tocopherol plasma level was lowered in the iron-supplemented groups, suggesting an increased utilization of vitamin E. These data show that pharmalogical doses of iron, associated with high vitamin C intakes, can result in uncontrolled lipid peroxidation. This is predictive of adverse effects for the mother and the fetus. This study illustrates the potential harmful effects of iron supplementation when prescribed only on the assumption of anemia and not on the bases of biological criteria.

Effect of increased fruit and vegetable intake on the susceptibility of lipoprotein to oxidation in smokers.

OBJECTIVE: To evaluate the effect of an increased dietary intake of fruit and vegetables on susceptibility of LDL to oxidation in smokers and nonsmokers. DESIGN: A descriptive and prospective study. SETTING: Joseph Fourier University, Grenoble. SUBJECTS: Volunteers were age and sex matched in the smoking and nonsmoking groups and were recruited by announcement. INTERVENTIONS: Increased intake of fruits and vegetables for two weeks providing 30 mg/day of carotenoids. MAIN OUTCOME MEASURES: Circulating levels of beta-carotene, lutein, lycopene, alpha-tocopherol; susceptibility of LDL to oxidation. Cu-Zn superoxide dismutase (Cu-Zn SOD), and Se glutathione peroxidase (Se-GSH-Px) activities and reduced (GSH) and oxidized (GSSG) glutathione. RESULTS: At entry (week 0: W0) smokers exhibited a lower plasma carotene level but the plasma parameters of oxidative stress and LDL oxidizability were not different from nonsmokers. After two weeks of increased intake of fruits and vegetables the circulating levels of carotenoids increased in smokers 23% and 11% in nonsmokers. At the same time the resistance of LDL to oxidation increased by 14% in smokers (P < or = 0.05) and by 28% in nonsmokers (P < or = 0.025). The mean whole blood GSH level was higher in smokers at entry but returned to a concentration similar to nonsmokers at the end of the study. CONCLUSION: This pilot study indicates that an increased, carotenoid rich food intake through its inhibitory effect on the susceptibility of LDL to oxidation may be an interesting approach to reduce the risk of atherosclerosis both in smokers and nonsmokers.

Mitochondrial respiratory activity and superoxide radical generation in the liver, brain and heart after chronic ethanol intake.

Functional characteristics of mitochondria isolated from liver, brain and heart were studied in ethanol-fed rats using ethanol administration in drinking water as a model of moderate alcohol intoxication. Our results show a slight decrease in liver cytochrome aa3 content, the mitochondrial alteration which is most consistently observed during chronic ethanol feeding. In liver and heart mitochondria, ethanol consumption led to an increase in state 3 respiration with NAD(+)-linked substrates, whereas no changes were apparent in respiration rates with succinate as substrate. However a decrease was found in state 3 respiration with succinate in brain mitochondria isolated from ethanol-fed rats. Submitochondrial particles (SMP) were used to study the superoxide radical (O2-.) production at the level of antimycin-inhibited regions of the respiratory chain. It appears that there is no clear correlation between ethanol effects on respiration and O2-. production. Whereas O2-. generation remained unchanged in heart mitochondria, an elevation of O2-. generation was observed in brain mitochondria, and in contrast, the rate of O2-. production was decreased in liver mitochondria of the ethanol-group in comparison to the control-group. Our findings support a tissue specificity for the toxic effects of ethanol towards the mitochondria and indicate that mitochondrial free radical mechanisms are involved in ethanol-induced toxicity in the brain.

Effects of chronic ethanol administration on free radical defence in rat myocardium.

Cellular protection against free radical reactions was measured in myocardium from ethanol-fed rats using ethanol administration in drinking water as a model of moderate alcohol intoxication. The activities of Cu,Zn-superoxide dismutase (SOD) and glutathione-S-transferase were higher in ethanol-fed rats than in controls, whereas Mn-SOD, catalase and glutathione peroxidase activities were not altered by ethanol treatment. Myocardial zinc was higher and selenium concentration lower in ethanol-fed rats than in controls. Ethanol consumption, which failed to modify the myocardial vitamin E level, did not result in increased lipid peroxidation, but decreased cytosolic and membraneous protein thiols.

Disturbances in myocardial creatine kinase following ethanol administration to rats--trials of prevention by allopurinol, desferrioxamine and propranolol.

A significant decrease in myocardial creatine kinase (CK) activity is apparent 2 hr after an acute ethanol load (2.3 g/kg, i.p.) in the rat. A lower dose (1.15 g/kg, i.p.), as well as ethanol addition in vitro up to 50 mM, do not affect this activity. Pretreatment with allopurinol (146 mumols/kg, i.p.) given at 16 hr and at 30 min before ethanol (2.3 g/kg) or with desferrioxamine (152 mumols/kg, i.p.) 30 min before ethanol failed to prevent the ethanol-induced decrease in CK activity. By contrast, propranolol (17 mumols/kg, i.p.), administered 30 min before ethanol elicited an enhanced CK activity in both control and ethanol-treated rats. This finding is likely related to the beta-blocking action and/or antioxidant properties of propranolol. Chronic ethanol intake (18% in calories) for 4 weeks also induced a decrease in myocardial CK activity, which could play a role in the pathogenesis of alcoholic cardiomyopathy.