Maud Andriollo-Sanchez

Zinc intake and status in middle-aged and older European subjects: the ZENITH study

Objective:Inadequate intakes of micronutrients in elderly negatively affect the nutritional status. Zinc is an essential micronutrient in the elderly, especially in relation to its impact on immune function, bone mass, cognitive function and oxidative stress. However, data are lacking on zinc intake and status during normal ageing. In this study, we evaluate the intake and status of zinc in late middle-aged and older free-living subjects.Design:Dietary zinc intake and zinc status in 188 middle-aged subjects from Clermont-Ferrand (Fr) and Coleraine (UK), and in 199 older subjects from Grenoble (Fr) and Roma (It) were assessed at the entry in the ZENITH study.Results:In relation to the zinc RDA for people older than 55 y, zinc intakes in most of the middle-aged and older subjects (more than 96%) in the present study were adequate. Older people had significantly lower (P<0.01) energy intakes as compared to middle-aged. Zinc intake expressed per MJ was also significantly (P<0.01) higher in older people compared to middle-aged. Erythrocyte and urinary zinc concentrations were significantly (P<0.001) higher in middle-aged subjects compared to older ones. The prevalence of biological Zn deficiency in free-living ageing European people was low (<5%).Conclusion:The results of the present study showed a relatively low prevalence of zinc deficiencies in healthy free-living late middle-age and older subjects. These results should be useful for health professionals to have reference data on zinc intake and status for a healthy ageing.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.

Age-related oxidative stress and antioxidant parameters in middle-aged and older European subjects: the ZENITH study.

Objective:Oxidative stress has been reported to increase with ageing. However, the data in healthy humans remain controversial and studies in free-living elderly people are scarce. The objective of the present study was to compare age-related oxidative stress in late middle-aged and older free-living subjects.Design:The effect of ageing on oxidative stress and antioxidant parameters was investigated in 188 middle-aged subjects from Clermont-Ferrand (France) and Coleraine (UK), and in 199 older subjects from Grenoble (France) and Roma (Italy). Plasma thiol (SH) groups, define definition (TBARs) and total glutathione (GSH), define definition (FRAP), and superoxide dismutase (SOD) activity were measured at baseline of the ZENITH study.Results:Plasma SH groups and FRAP and, surprisingly, TBARs were significantly lower in free-living older subjects compared to younger subjects (P<0.001, P<0.001, P<0.01, respectively), but there was no significant differences in GSH levels.Conclusion:European free-living healthy older do not appear to be exposed to an acute oxidative stress. However, the highly significant positive correlation between plasma SH group oxidation or decreased FRAP and ageing is predictive of an increased risk of oxidative stress in older subjects. Moreover, the comparison between middle-aged and older subjects regarding oxidative stress parameters suggests also a progressive and slow decline of antioxidant status in healthy free-living older elderly and underline the impact on life-style factors on successful ageing.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.

Zinc status and taste acuity in older Europeans: the ZENITH study

Background:Age-related decline in taste acuity may be both a cause and an effect of depleted zinc and/or increased zinc requirement.Objective:The aim of this study was to explore associations between zinc status and taste acuity in healthy older European adults aged 55–90 y.Sample:Volunteers were recruited within Italy (n=108 aged 70–90 y), the United Kingdom (UK) (n=93 aged 55–70) and two regions of France (n=186), Grenoble (aged 70–90 y) and Clermont-Ferrand (aged 55–70 y).Methods:A signal detection theory approach was adopted, employing a three-alternative, forced-choice procedure. The data were converted to R-indices and bivariate correlations were computed to explore relationships between serum zinc, erythrocyte zinc and taste acuity. ANOVA was undertaken to determine regional differences in zinc status.Results:Higher erythrocyte zinc status was associated with better acuity for salt (sodium chloride) taste in the sample as a whole (P=0.012) (n=385). Higher serum zinc levels were associated with greater sensitivity to sour taste (citric acid) (P=0.015) only in the older groups (aged 70–90 y). There were no apparent associations between serum or erythrocyte zinc status and acuity for bitter (quinine) or sweet (sucrose) tastes irrespective of age.Conclusion:These results agree with those previously suggesting that age-related detriment in sensitivity for salt taste may be associated with depleted zinc.Sponsorship:ZENITH is supported by the European Commission ‘Quality of Life and Management of Living Resources’, Fifth Framework Programme, Contract no. QLK1-CT-2001-00168.

Effects of zinc supplementation on cognitive function in healthy middle-aged and older adults: the ZENITH study

A randomised double-blind placebo-controlled design was employed to investigate the effects of Zn supplementation on cognitive function in 387 healthy adults aged 55-87 years. Several measures of visual memory, working memory, attention and reaction time were obtained using the Cambridge Automated Neuropsychological Test Battery at baseline and then after 3 and 6 months of 0 (placebo), 15 or 30 mg Zn/d. Younger adults (< 70 years) performed significantly better on all tests than older adults (> 70 years), and performance improved with practice on some measures. For two out of eight dependent variables, there were significant interactions indicating a beneficial effect (at 3 months only) of both 15 and 30 mg/d on one measure of spatial working memory and a detrimental effect of 15 mg/d on one measure of attention. Further work is required to establish whether these findings generalise to older adults in poorer mental and physical health and with less adequate Zn intake and status than the present sample.

Food chromium content, dietary chromium intake and related biological variables in french free-living elderly

Trivalent chromium (Cr3+) is an essential trace element involved in insulin function. Cr deficiencies result in decreased insulin sensitivity, glucose intolerance and an increased risk of diabetes. Cr status decreases with age suggesting that the elderly may be at high risk of Cr deficiency. This study aimed to provide information about the Cr content of foods in France and the Cr intake in French free-living elderly. We measured the food Cr content and daily Cr intake of freely chosen diets for 3 d in twelve French free-living elderly people and their Cr excretion and plasma hormonal related variables, leptin, insulin and cortisol. Considering the relationship between insulin resistance and oxidative stress, we also determined plasma thiobarbituric acid reactive substance, thiol groups and total and reduced glutathione. Although these subjects had well-balanced diets, their daily Cr intakes did not reach the French recommendations. The low Cr intakes were due to the low Cr density of the foods. We found a negative correlation between Cr intakes and insulin, BMI and leptin.

Estimation of intake and status of vitamin A, vitamin E and folate in older European adults: the ZENITH

Objective:To report selected dietary intake and vitamin status at baseline of volunteers participating in the ZENITH study and the correlation of vitamin status with zinc.Design:A multicentre prospective intervention study employing a randomised double-blind design.Setting:Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy).Participants:In total, 387 healthy middle-aged (55–70 y) and older (70–87 y) men and women participated in the study.Methods:Dietary intake was assessed by means of a validated 4-d recall record. Fasting blood samples were simultaneously analysed for retinol and α-tocopherol by the HLPC method. Erythrocyte folates were measured by a competitive immunoassay with direct chemiluminescence detection on an automatised immunoanalyser.Results:In all centres, men had a significantly (P<0.0001) higher mean nutrient intake than women. Comparison between age-groups showed that older individuals had significantly lower intakes of macro- and selected micronutrients than middle-aged subjects (P<0.0001). A high fat intake (from 36 to 40% of total energy) was observed in all examined groups. In relation to biochemical measures of vitamin status, all parameters were above their respective cut-off values for normality and, thus, none of the subjects had biochemical evidence of deficiency of these selected vitamins. A moderate correlation was found with plasma vitamin A and serum zinc (r=0.12, P<0.05) or red blood cell zinc (r=0.12, P<0.01) and with erythrocyte folates and red blood cell zinc (r=0.11, P<0.05).Conclusions:There were only moderate differences in the nutrient intake of the ZENITH study volunteers among the four European centres. Their biochemical status for retinol, α-tocopherol and folate appeared adequate.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’, Fifth Framework Programme, Contract no. QLK1-CT-2001-00168.

The relationship between the zinc nutritive status and biochemical markers of bone turnover in older European adults: the ZENITH study

Objective:To investigate the relationship between indices of zinc nutritive status and biochemical markers of bone turnover in older adult European subjects.Design:Use of baseline data from a multicentre prospective zinc intervention (ZENITH) study.Setting:Centres in France, Italy and Northern Ireland.Participants:A total of 387 healthy adults, aged 55–87 y.Methods:Zinc intake was assessed by 4-day recall records. Circulating and urinary biochemical zinc status measures were assessed by atomic absorption spectrophometry. Serum bone-specific alkaline phosphatase and osteocalcin were assessed by ELISA and urinary pyridinoline (Pyr) and deoxypyridinoline (Dpyr) by HPLC.Results:Zinc intake was negatively correlated with urinary Pyr and Dpyr (r=−0.298 and −0.304, respectively; P<0.0001), but was not correlated with bone formation markers. There was a tendency for serum zinc to be negatively correlated with urinary Dpyr (r=−0.211; P=0.080). Erythrocyte zinc was negatively correlated with serum osteocalcin (r=−0.090; P<0.0001). None of the other correlations were significant. After adjustment for confounder (age, gender and research centre) the only significant association that remained was between serum osteocalcin and erythrocyte zinc (β=−0.124; P=0.011).Conclusions:There was some, albeit inconsistent, evidence of a relationship between zinc nutritive status and bone turnover in the older adult participants of the ZENITH study.Sponsorship:ZENITH is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.

Interleukin-6, TNF-alpha and interleukin-1 beta levels in blood and tissue in severely burned rats

Previous studies have demonstrated the early appearance of inflammatory cytokines in the systemic circulation after thermal injury both in humans and animals. The aim of this study was to evaluate the time course of several cytokines, IL-6, TNF-alpha and IL-1beta in serum, lung, liver and brain of severely burned rats during the first week after thermal injury. Cytokine measurements were performed by enzyme-linked immunosorbent assay (ELISA). The comparison between the sham-burned animals and animals with third-degree burns on 20% or 40% of their total body surface area allowed for the study of the inflammatory process relative to the size of the injury. Serum IL-6 levels, which were undetectable in sham-treated animals, peaked during the first hours after injury and were proportionate to the size of the area burned. After a few days, IL-6 increased once more, but only in the most severely burned rats. In lung, liver and brain, low but measurable basal levels of TNF-alpha and IL-1 were detected in sham-burned animals. Strikingly, IL-1beta levels remained significantly elevated in the lung after injury in animals having 20% and 40% burned skin area. Unexpectedly, both TNF-alpha and IL-1beta production decreased gradually in liver and brain after burn injury. Also, the inflammatory response after a burn injury appeared to be biphasic. The first period corresponded to the early release of IL-6 into the circulation, proportional to the severity of the injury. After a few days, a second period was marked by the extension of the inflammatory processes from the injured area to the rest of the body, particularly to lung, which could be considered as at potential risk of involvement in severely burned patients.

Screening and recruitment procedure of late-middle aged and older subjects: the ZENITH study.

Objective:To report the rational, design, recruitment, baseline characteristics and preliminary overview of volunteers in the ZENITH study.Design:A multicentre prospective intervention study employing a randomised double-blind design.Setting:Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy).Participants:Healthy men and women middle-aged (55–70 y) and older volunteers (70–87 y).Interventions:At baseline (prior to zinc (Zn) supplementation), all volunteers underwent a full clinical examination, anthropometric measurements, health and lifestyle questionnaire, Mini Mental State Examination, Geriatric Depression Scale, and biochemistry profile.Results:In total, 842 volunteers (378 men and 464 women) were invited to take part in the study. A total of 49% of these volunteers were excluded on the basis of inclusion/exclusion criteria. In total, 433 participants were admitted to the Zn supplementation for 6 months. During this period, about 10% of volunteers dropped out from the study.Conclusions:A total of 387 subjects (197 male and 190 female subjects) successfully completed the supplementation phase of the ZENITH study.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.

Health and lifestyle characteristics of older European adults: the ZENITH study.

Objective:To describe health and lifestyle factors of participants in the ZENITH study.Design:A prospective multicentre intervention study employing a randomised double-blind design.Participants:Community dwelling older adults (n=387), aged 55–87 y were recruited from regions in France, Italy and the UK.Intervention:A self-report questionnaire comprising socio-demographic variables, dietary habits, physical activity in the home, at work and recreation.Results:Participants differed with regards dietary habits and physical activity for each region. Recreational activity was higher in France and women generally tend to perform less hours of recreational activity per week than men.Conclusions:The differences found for these regions of Europe in relation to lifestyle factors will affect health and well-being within these countries and may mediate the impact of zinc supplementation on various biological and psychological parameters.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.