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H Faure

Publications and source records attributed to H Faure.

At least 19 recordsLinked to original sources
PubMed2006

Factors influencing blood concentration of retinol, alpha-tocopherol, vitamin C, and beta-carotene in the French participants of the SU.VI.MAX trial.

OBJECTIVES: The data was collected during the inclusion step of the SUpplémentation en VItamines et Minéraux AntioXydants (SU.VI.MAX) study. This article deals with the study's first stage before any supplementation. The collected data shows factors influencing blood vitamin concentrations and may reflect the vitamin status of volunteers. MATERIAL AND METHODS: A total of 12,741 volunteers were enrolled in the SU.VI.MAX study 7,713 women 35-60 years of age and 5,028 men 50-60 years of age. The serum concentrations of retinol, alpha-tocopherol, and beta-carotene were measured by HPLC, and vitamin C concentration was measured by spectrofluorimetry using a Technicon continuous flow analysis apparatus. The volunteers recorded their 24 h diet by means of a specific terminal that was connected to the main central computer of the SU.VI.MAX study. Volunteers recorded the food they consumed daily and estimated its quantity by comparing pictures of dishes. RESULTS: Retinol concentration was significantly higher in older volunteers, and was higher in male than in female volunteers. Smoking had no effect on serum retinol, but the latter was higher in the autumn than in the winter. Serum retinol concentrations were higher in the Southwest region and lower in the Ile-de-France and East-Centre regions. Serum alpha-tocopherol was slightly higher in older volunteers and also higher in male volunteers. Serum alpha-tocopherol was significantly lower in smokers, and former smokers showed intermediate levels. Like retinol, serum alpha-tocopherol was higher in the autumn, and higher in the Southwest as compared to the East-Centre Serum beta-carotene was slightly higher in younger volunteers, and concentrations were higher in female than in male volunteers. Tobacco smoking decreased serum beta-carotene, which was higher in the autumn, and higher in the East, West, and North regions. Serum vitamin C was higher in female volunteers, and was not age related. Serum vitamin C was lower in smokers, was season-dependant, but contrary to fat-soluble vitamins, concentrations were higher in the winter and spring. Serum vitamin C was higher in the Southeast and East-Centre, but lower in the North region. CONCLUSION: These results suggest that serum retinol concentrations depend on gender, age, seasons, and location of residence. Similarly, serum alpha-tocopherol concentrations were slightly influenced by age, but more by tobacco smoking, seasons, dietary intake, and location of residence. Serum concentrations of beta-carotene depend on gender, age, smoking status, dietary intake, and location of residence. Serum vitamin C concentrations depend on gender, age, smoking status, seasons, dietary intake, and location of residence. Contrary to beta-carotene, retinol concentrations were higher in male than in female volunteers. Such a reversed relation suggests a higher beta-carotene-retinol conversion in male volunteers.

Adult↗
PubMed2005

Serum concentrations of beta-carotene, vitamins C and E, zinc and selenium are influenced by sex, age, diet, smoking status, alcohol consumption and corpulence in a general French adult population.

OBJECTIVE: To assess relationships between energy, nutrient and food intakes, alcohol consumption, smoking status and body mass index (BMI), and serum concentrations of beta-carotene, alpha-tocopherol, vitamin C, selenium and zinc. METHODS: Data on health status, alcohol consumption, smoking habits, anthropometric data and biochemical measurements were obtained in 1821 women aged 35-60 y and 1307 men aged 45-60 y, participant to the SU.VI.MAX Study. Data on dietary intake were available on a subsample who reported six 24-h dietary records during the first 18 months of the study. RESULTS: Women had higher baseline serum beta-carotene and vitamin C concentrations and lower concentration for serum vitamin E, zinc and selenium than men. In women, younger age was associated with lowered mean concentration of serum beta-carotene, vitamin E and selenium. In men, only differences were observed for serum zinc, which was lower in older men. Current smokers of both sexes had significantly lower concentrations of serum beta-carotene, vitamin C and selenium, and, only in women, of vitamin E, than nonsmokers. Alcohol consumers had lower concentrations of serum beta-carotene and higher selenium concentrations. Serum beta-carotene and vitamin C concentrations were lower in obese subjects. There were positive associations of dietary beta-carotene, vitamin C and E with their serum concentrations. Age, nutrient and alcohol intakes, serum cholesterol, BMI and smoking status explained 15.2% of the variance of serum beta-carotene in men and 13.9% in women, and 10.8 and 10.0% for serum vitamin C, and 26.3 and 28.6% for serum vitamin E, respectively. CONCLUSION: Serum antioxidant nutrient concentrations are primarily influenced by sex, age, obesity, tobacco smoking, alcohol consumption and especially dietary intake of those antioxidant nutrients.

Adult↗
PubMed2004

Assessment of DNA damage by comet assay on frozen total blood: method and evaluation in smokers and non-smokers.

This study was undertaken with the aim to develop an optimised protocol for the evaluation of DNA damage in frozen whole blood. This was achieved by use of the single-cell gel electrophoresis (SCGE) or comet assay in its alkaline version. After collection of blood, the total blood sample was mixed with dimethyl sulfoxide (DMSO), a cryoprotectant commonly used for prevention of freezing-induced damage to living cells, and then stored at -80 degrees C. We observed no statistically significant differences in the level of DNA damage between fresh blood samples and frozen blood samples, as assessed by the comet assay. Considering the absence of effects of the freezing step, a frozen blood sample was included as a control sample in subsequent experiments. Thus the protocol was applied to blood samples of twenty healthy subjects including smokers and non-smokers. The comparative analysis indicated that the level of DNA damage was 56% higher in smokers than in non-smokers (P = 0.01). Altogether, this study strongly suggests that frozen whole blood could be utilised in association with the comet assay in human epidemiological bio-monitoring for the assessment of genetic damage in populations at risk.

Blood↗
PubMed2004

Hedgehog interacting protein in the mature brain: membrane-associated and soluble forms.

Hedgehog interacting protein (Hip) is considered as a membrane protein implicated in sequestering the hedgehog (hh) morphogens during embryonic development. Here, we demonstrate that Hip transcription also occurs in cells scattered in discrete brain areas of adult rodents and we identify the presence of membrane-associated and soluble forms of Hip in the mature brain. Moreover, we show that soluble forms of Hip, present in the conditioned medium of HEK293 cells overexpressing Hip, inhibit Sonic hedgehog (Shh)-induced differentiation of C3H10T1/2 cells, a well-characterised response associated with Shh signalling. After transfection in HEK293 cells, Hip partitions with the raft component ganglioside GM1 during density gradient centrifugation. Analysis of tagged Hip constructs reveals that the putative transmembrane domain of Hip is not cleaved suggesting that other mechanisms are implicated in the release of its soluble forms. Taken together, these data are consistent with the involvement of both membrane-associated and soluble Hip in the regulation of Shh signalling in adult neural tissues.

Animals↗
PubMed2004

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.

Adult↗
PubMed2001

Blood micronutrients in Algeria, relationships with sex and age.

Despite trace elements and vitamins are major public health problems in some African countries, there are few studies reporting micronutrient status in North Africa. Therefore, it could be interesting to evaluate plasma concentrations of vitamin A, E and beta-cartene, along with zinc, copper, selenium erythrocyte glutathione peroxidase and superoxide dismutase in Algeria. Volunteers were randomly recruited in Constantine, Batna and Mila. Vitamins, trace elements and enzymes were measured in the University Hospital of Grenoble. 455 persons were included in the study. Subjects were divided in 3 groups: group I: 15 girls and 12 boys who were 6 to 12.9 years old, group II: 190 women and 192 men 13 to 49.9 years old, group III: 24 women and 24 men 50 to 65 years old. Plasma concentrations of micronutrients and enzymes are close to those commonly observed in Europe, except for vitamin A concentrations. Indeed, retinol levels are 30-35% lower than those reported in European countries, moreover almost 8% of the population showed retinol concentrations less than 1.05 mumol/l. beta-Carotene levels were also lower than in the French average population. Ten per cent of the population had plasma zinc levels lower than 10.6 mumol/l. Vitamin E, copper and selenium status seems satisfactory in Algeria. Vitamin A is not a public health problem, however a significant percentage of residents exhibits impaired vitamin A levels and may benefit from retinol supplementation. Larger studies are needed, and particularly in children, to detect possible higher prevalence of vitamin A deficiency in poor socio-economical classes and in inner geographic areas.

Adolescent↗
PubMed2001

High expression and anterograde axonal transport of aminoterminal sonic hedgehog in the adult hamster brain.

Sonic hedgehog (SHH) is considered to play an important role in tissue induction and patterning during development, particularly in determining neuronal cell fate in the ventral neural tube and in the embryonic forebrain. SHH precursor is autoproteolytically cleaved to an aminoterminal fragment (SHHN) which retains all known SHH biological activities. Here, we demonstrate the expression of a 22-kDa SHHN immunoreactive peptide in developing and adult hamster brain regions using a rabbit antiserum directed against a mouse SHHN fragment. Interestingly, SHHN was developmentally regulated with the highest expression observed in the adult brain, was resistant to Triton X-100 solubilization at 4 degrees C and partitioned with the raft component ganglioside GM1 during density gradient centrifugation. In rat brain, Shh transcripts were identified by double in situ hybridization in GABAergic neurons located in various basal forebrain nuclei including globus pallidus, ventral pallidum, medial septum-diagonal band complex, magnocellular preoptic nucleus and in cerebellar Purkinje cells as well as in motoneurons of several cranial nerve nuclei and of the spinal cord. We show that radiolabelled SHHN peptides are synthesized in the adult hamster retina and are transported axonally along the optic nerve to the superior colliculus in vivo. Our data indicate that SHHN is associated with cholesterol rich raft-like microdomains and anterogradely transported in the adult brain, and suggest that the roles of this extracellular protein are more diverse than originally thought.

Age Factors↗
PubMed2001

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.

Adult↗
PubMed2001

Selenium status in an iodine deficient population of the West Ivory Coast.

Selenium is an essential trace element which is part of the active site of seleno-dependent glutathione peroxidase and type 1 deiodinase. Therefore, it plays a key role in thyroid hormone metabolism. The present work was undertaken in order to evaluate selenium status in two Ivory Coast populations: the first with high (Glanlé) and the second with low (Abidjan) prevalence of iodine deficiency. Selenium, glutathione peroxidase, glutathione reductase, glutathione and diglutathione were determined in blood and/or urine. In plasma and erythrocytes, selenium and glutathione peroxidase were dramatically low in Glanlé. Compared to Abidjan, selenium, glutathione peroxidase, vitamin E and riboflavin status were decreased whereas diglutathione was increased in Glanlé. The results clearly demonstrate a selenium deficiency and suggest an oxidant stress in Glanlé. Causes and consequences of this selenium deficiency and oxidant stress remain to be determined.

Anthropology, Cultural↗
PubMed2001

Effect of two years' supplementation with natural antioxidants on vitamin and trace element status biomarkers: preliminary data of the SU.VI.MAX study.

The "SUpplementation en VItamines et Minéraux AntioXidants" (SU.VI.MAX) study is a randomized double-blind, placebo controlled, primary-prevention trial designed to test the efficacy of a daily supplementation with antioxidant vitamins (vitamin C, 120 mg; vitamin E, 30 mg; and beta-carotene, 6 mg) and minerals (selenium, 100 microg; and zinc, 20 mg) at nutritional doses (one to three times the daily recommended dietary allowances), in reducing the frequency of cancers and cardiovascular diseases. The study involves 12,735 eligible subjects (women aged 35-60 years, men aged 45-60 years) included in 1994 in France. They will be followed up for 8 years. The targeted population is the general population. The aim of this specific analysis is to assess the effect of 2 years of supplementation on biochemical indicators of vitamin and trace element on a subsample of 1000 subjects. The mean (+/- standard deviation) concentrations of plasma beta-carotene, alpha-tocopherol, vitamin C, selenium and zinc among participants who were randomly assigned to receive a daily supplementation with beta-carotene, vitamin E, vitamin C, selenium and zinc for 2 years were significantly higher than those who were assigned to receive placebo. Specifically, the mean concentrations among men in the intervention group were 0.86 +/- 0.70 micromol/L for beta-carotene, 35.3 +/- 9.3 micromol/L for alpha-tocopherol, 11.5 +/- 4.7 microg/ mL for vitamin C, 1.65 +/- 0.33 micromol/L for selenium, and 16.2 +/- 3.9 micromol/L for zinc. The mean concentrations among women in the intervention were 1.25 +/- 0.90 micromol/L for beta-carotene, 34.9 +/- 8.4 micromol/L for alpha-tocopherol, 12.6 +/- 4.0 microg/mL for vitamin C, 1.68 +/- 0.37 micromol/L for selenium, and 15.3 +/- 3.9 micromol/L for zinc. The values observed for beta-carotene and vitamin E in the supplementation group after 2 years of intervention are those that have been associated with the lowest risk of cancer in observational studies. They are definitely lower than concentrations reported in intervention studies showing an apparent negative effect of high levels of beta-carotene supplementation on the lung cancer incidence rate in high-risk subjects (initial level multiplied by 12-18). Data from the follow-up will ascertain if any plausible reduction in the incidence rate of cancers may be associated with such amounts of antioxidant agents.

Adult↗
PubMed2000

N1-Arylsulfonyl-N2-(1-aryl)ethyl-3-phenylpropane-1,2-diamines as novel calcimimetics acting on the calcium sensing receptor.

The synthesis and calcimimetic properties of N1-arylsulfonyl-N2-(1-aryl)ethyl-3-phenylpropane-1,2-diamines are described. The most active compound of the series (3n, used at 10 microM) produced 97+/-11% of the maximal stimulation of [3H]IP production obtained by 10 mM Ca2+ in CHO cells expressing the calcium sensing receptor (CaSR). This calcimimetic activity was due to a specific interaction of this compound with the CaSR.

Animals↗
PubMed1999

Gas chromatographic-mass spectrometric determination of total homocysteine in human plasma by stable isotope dilution: method and clinical applications.

The detection and quantitation of slight increases of plasma homocysteine levels is of growing interest. This has prompted us to develop a highly sensitive and accurate capillary gas chromatography-mass spectrometry (GC-MS) method. The method proved to be highly sensitive (DL=0.17 micromol/l) with between- and within-run precision less than 6% and 7%, respectively. Reference values of plasma total homocysteine have been determined for men (n=39) and women (n=36), showing a significant difference (P=0.003) between gender. Preliminary results in cerebrovascular accidents and in venous thrombosis are presented.

Adult↗
PubMed1999

Plasma vitamin A, E, and beta-carotene levels in adult post-partum Algerian women.

Vitamins A and E are essential for foetal growth, reproduction, and lactation. In this article we report the results of a study, lead in three Eastern Algeria cities, that involved 786 post-partum women and 250 control. Plasma levels of vitamins A, E, beta-carotene, and some nutritional indexes were measured in both groups. In control women, plasma retinol and beta-carotene levels were significantly lower in Algeria than in France (retinol: 1.4 +/- 0.42 vs. 1.78 +/- 0.53 mumol/l; beta-carotene: 0.35 +/- 0.261 vs. 0.94 +/- 0.611). These differences could be the consequence of different beta-carotene and retinol intakes. In Algeria, comparisons between post-partum women and controls, showed that plasma vitamin A and beta-carotene levels were significantly lower in post-partum than in control women. This fact, and the lower level of retinol in control women, raises the question of supplementation for pregnant women in Algeria, at least for those with the lowest standard of living whose protein and zinc levels are also very low after delivery. Plasma vitamin E levels and vitamin E/total lipid ratios were not different in Algeria and in France. Vitamin E concentration was higher during pregnancy, but the vitamin E/total lipid ratio was significantly lower, which shows a relative deficiency at the end of pregnancy. Comparisons of plasma vitamin E levels, at delivery, in primiparous and in multiparous women reveal a better tocopherol status in multiparous women. This difference could reflect an adaptive response to oxidative stress in multiparous women.

Adolescent↗
PubMed1999

Discrete localizations of hedgehog signalling components in the developing and adult rat nervous system.

Sonic hedgehog (Shh), a morphogen molecule implicated in embryonic tissue patterning, displays inductive, proliferative, neurotrophic and neuroprotective activities on various neural cells. Shh might exert its biological functions through binding to patched (Ptc) associated with smoothened (Smo), leading to downstream activation of target genes such as the transcription factor Gli1. We have performed a detailed localization of cells expressing transcripts of Shh, Ptc, Smo and Gli1 in brain and spinal cord of the adult rat as well as in the developing cerebellum. In the adult, Shh-positive cells were mainly observed in forebrain structures, in the Purkinje cells of the cerebellum and in motor neurons. Ptc-positive cells were frequently observed in brain areas devoid of any Shh transcripts, except in the median eminence or the facial nucleus, suggesting local Shh signalling. Interestingly, Smo transcripts were predominantly present within circumventricular organs, in granular cells of the dentate gyrus and in neurons of the reticular thalamic nucleus. The presence of Shh, Ptc and Smo transcripts in hypothalamic areas may indicate a role of Shh signalling in the modulation of neuroendocrine functions. The expression pattern of these three genes as well as of Gli1, and their developmental regulation in the cerebellum, suggest a possible role for Hedgehog signalling in the control of various cell populations within the cerebellum, particularly in granule cell proliferation and/or differentiation that might be impaired in proliferative states such as medulloblastomas.

Animals↗
PubMed1999

Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine and 5-(hydroxymethyl) uracil in smokers.

Cigarette smoke is known to generate free radicals by various mechanisms. In this study involving 30 non-smokers and 30 smokers, we show that urinary excretion of 5-(hydroxymethyl) uracil (HMUra) was not different in the two groups (6.54+/-2.07 vs. 6.70+/-1.68 nmol/mmol creatinine). In contrast, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo) excretion increased by 16% (1.16+/-0.35 vs. 1.35+/-0.50 nmol/mmol creatinine, p = 0.039). Results concerning 8-oxo-dGuo are in agreement with those of previous studies. We observed significant multiple correlations between HMUra and creatinine (r(p) = 0.44), BMI (r(p) = -0.27) and nicotine derivatives (r(p) = 0.26). Multiple correlation analysis showed relations between 8-oxo-dGuo on the one hand, and: creatinine (r(p) = 0.36), nicotine derivatives (r(p) = 0.29), BMI (r(p) = -0.24) on the other.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1999

[Carotenoids: 2. Diseases and supplementation studies].

Inverse correlations have been found in most studies on the relationship between dietary intake and plasma concentrations of carotenoids on one side and degenerative diseases such as cancer and cardiovascular diseases on the other side. Protective effects of carotenoids have been found for pathologies of the retina and the skin. Concentrations of these molecules in blood are lower in digestive pathologies and HIV. Short- and long-term toxicity of carotenoids was found to be low. In combination with the beneficial effects found for diets rich in carotenoids, this has initiated trials with relatively high doses of carotenoid supplements. In the study in Linxian (China) in a rural population with poor nutritional status, supplementation with beta-carotene, zinc, selenium and vitamin E lowered total mortality and mortality from stomach cancer. Other studies (ATBC, Caret.) on well-fed subjects did not show beneficial effects on mortality from cancer and cardiovascular diseases. On the contrary, higher mortality and lung cancer incidence was found in supplemented subjects that were also exposed to asbestos and cigarette smoke. In these studies, doses of supplemental beta-carotene were high and varied from 20 to 50 mg/day. One still ongoing study, called Suvimax, doses subjects for eight years with a cocktail of vitamins and minerals including 6 mg per day of beta-carotene. This supplementation with physiologically seen more "normal" doses might give clarity on the question if beta-carotene is the protective factor in fruits and vegetables.

Anticarcinogenic Agents↗
PubMed1998

Urinary excretion of 5-(hydroxymethyl) uracil in healthy volunteers: effect of active and passive tobacco smoke.

The urinary excretion of 5-(hydroxymethyl)uracil (5-HMUra), one of the major oxidative modifications of thymine, was investigated in 134 healthy volunteers living in North Italy. Overnight urine was collected, and a questionnaire was completed on smoking habits and exposure to environmental tobacco smoke (ETS). 5-HMUra was analyzed by GC/MS, following urine purification by HPLC. 5-HMUra excretion showed an approximately normal distribution, ranging from 0.08 to 0.84 (mean 0.44) nmoles/kg/8 hr and from 3.2 to 18.7 (mean 8.5) nmoles/mmoles creatinine. 5-HMUra excretion was significantly higher in women than in men and in smokers than in non-smokers when results were expressed as the ratio to creatinine. Slightly higher levels of 5-HMUra excretion, expressed as nmoles/mmoles creatinine, were also found in subjects highly exposed to ETS, monitored either as the number of hours of exposure or as the number of smokers in the workplace and at home. Our results show that the urinary excretion of 5-HMUra is higher than that of other oxidized nucleobases, including 8-oxo-7,8-dihydroguanine, and can be slightly modified by environmental factors such as tobacco smoke. These findings suggest that measurement of urinary excretion of 5-HMUra could be useful as a biomarker of oxidative DNA damage and repair, though further research is needed to support these data.

Adult↗