Insulin but not leptin protects olfactory mucosa from apoptosis.

The mammalian olfactory mucosa (OM) is continually renewed throughout life. Owing to their position in the nasal cavity, OM cells are exposed to multiple insults, including high levels of odourants that can induce their death. OM regeneration is therefore essential to maintain olfactory function, and requires the tight control of both cell death and proliferation. Apoptosis has been implicated in OM cell death. Olfaction is one of the senses involved in food intake and depends on individual nutritional status. We have previously reported the influence of hormones related to nutritional status on odour perception and have shown that the OM is a target of insulin and leptin, two hormones known for their anti-apoptotic properties. In the present study, we investigated the potential anti-apoptotic effect of these metabolic hormones on OM cells. Both Odora cells (an olfactive cell line) and OM cells treated with etoposide, a p53 activity inducer, exhibited mitochondrial-dependent apoptosis that was inhibited by the pan-caspase inhibitor zVAD-fmk. Insulin, but not leptin, impaired this apoptotic effect. Insulin addition to the culture medium reduced p53 phosphorylation, caspase-3 and caspase-9 cleavage, and caspase-3 enzymatic activity induced by etoposide. The apoptotic wave observed in the OM after interruption of the neuronal connections between the OM and the olfactory bulb by bulbectomy was impaired by intranasal insulin treatment. These findings suggest that insulin may be involved in OM cellular dynamics, through endocrine and/or paracrine-autocrine effects of circulating or local insulin, respectively.

Preservation of micronutrients during rapeseed oil refining: a tool to optimize the health value of edible vegetable oils? Rationale and design of the Optim'Oils randomized clinical trial.

Numerous micronutrients naturally abundant in oilseeds prevent the risk of cardiovascular diseases by reducing cholesterolemia and oxidative stress. These micronutrients include phytosterols and various antioxidants such as polyphenols, tocopherols and coenzyme Q10/Q9 but most of them are lost during the oilseed oil refining. The main objective of the Optim'Oil project was to modify the processes of oil refining in order to reduce the lost of micronutrients. Two clinical trials (cross-over, monocentric, randomized, double-blind and controlled) were designed to investigate the effect of an optimized rapeseed oil 1) on cardiovascular biomarkers (long-term study) and 2) on oxidative stress parameters (post-prandial study). For the long-term study, 59 volunteers ingested daily 20 g of oil and 22 g of margarine (optimized or standard) for 2 periods of 3 weeks separated by a 3-week wash-out period. Blood samples were collected at the beginning and at the end of each period. For the post-prandial study, a sub-group of 16 volunteers came fasted at the laboratory and took 300 mL of a test meal containing 60% of the optimized or standard oils. Blood samples were collected before and during 6h after the test meal intake. In comparison with the standard oil and margarine, the optimized oil and margarine exhibit as expected an increased content of phytosterol (+22%), polyphenols (× 11), tocopherols (+131%) and coenzyme Q10/Q9 (+165%). Overall, conditions of this study were relevant to investigate the effect of the optimized rapeseed oil and margarine on the cardiovascular risk and the oxidative stress.

Effect of zinc supplementation on vitamin status of middle-aged and older European adults: the ZENITH study.

OBJECTIVE: To assess the effects of zinc supplementation on vitamin status in middle-aged and older volunteers. SUBJECTS/METHODS: Three hundred and eighty-seven healthy middle-aged (55-70 years) and older (70-85 years) men and women, randomly allocated to three groups to receive 15 or 30 mg Zn/day or placebo for 6 months. Dietary intake was assessed by means of a validated 4-day recall record. Fasting blood samples were simultaneously analysed for levels of plasma retinol and alpha-tocopherol by high-performance liquid chromatography. Erythrocyte folates were measured by a competitive immunoassay with direct chemiluminescence detection on an automatized immunoanalyser. Biochemical measurements were performed at baseline and after 3 and 6 months of zinc supplementation. RESULTS: Plasma vitamin A levels were significantly increased proportionally with zinc dose and period of treatment, particularly at 6 months (for 15 mg Zn/day, P<0.05; for 30 mg Zn/day, P<0.0001); no significant changes were observed in the placebo group. There was no effect of zinc supplementation on vitamin E/cholesterol ratio and erythrocyte folates. CONCLUSIONS: Our results show that a long-term zinc supplementation increases plasma vitamin A levels in middle-aged and older people of similar characteristics to those involved in this study. Moreover, supplementation influences serum zinc levels but does not affect erythrocyte zinc concentration and both plasma vitamin E and erythrocyte folate status.

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.

Positive and negative mood in the elderly: the ZENITH study.

OBJECTIVE: To assess the quality of positive and negative affect (mood) in an ageing European sample. BACKGROUND: Mood quality has important implications for both physical and mental wellbeing. Poor quality moods are associated with deficits in the diverse areas of cognitive function, health, and social relationships. The ageing process presents a number of potential challenges to successful mood regulation that could have wider implications. DESIGN AND PARTICIPANTS: The current study examines the quality of positive and negative affect in 387 healthy participants from three European countries. Moods were measured four times a day for 4-7 d with the Positive and Negative Affect Schedule (PANAS) mood scales. Measures of zinc (Zn) status were taken also. SETTING: Two centres concentrated on 55-70 yr olds (Coleraine, N.Ireland, n = 93 and Clermont-Ferrand, France, n = 95), and two centres concentrated on 70-87 yr olds (Rome, Italy, n = 108, and Grenoble, France, n = 91). RESULTS: Positive affect scores for the centre in Rome were significantly (P < 0.01) lower than for the other three centres, and the Grenoble centre had significantly (P < 0.05) higher scores on negative affect than the other three centres. Mood was not related to measures of zinc status (all Ps > 0.05). CONCLUSIONS: The two centres with the oldest participants showed deficits in mood quality that may have implications for broader well-being.

Cognitive function in healthy older European adults: the ZENITH study.

OBJECTIVE: Baseline data are reported from a study of the effects of zinc supplementation on cognitive function in older adults as assessed by the CANTAB computerised test battery. DESIGN: This is a multicentre prospective intervention study employing a randomised double-blind design. SETTING: European community-based study. PARTICIPANTS: There are 387 healthy adults aged 55-87 y from centres in France, Italy and Northern Ireland. INTERVENTIONS: Measures of visual memory, working memory and attention were obtained at baseline (prior to supplementation). RESULTS: Younger adults (<70 y) performed significantly better than older adults (>70 y) on all tests, with minimal differences between centres. In addition, men outperformed women on tests of spatial span, pattern recognition memory and reaction times, although these gender differences varied somewhat between centres. CONCLUSIONS: The results are generally consistent with previous age- and gender-related effects on cognitive functioning.

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.

Gonadal steroids and bone metabolism in young castrated male rats.

At 45 days of age, 40 male Wistar rats were castrated, then randomly divided into four groups, S.C. injected for 60 days after surgery either with 17beta-estradiol (E) 10 microg/kg BW/48 hours, progesterone (P) 140 microg/kg BW/48 hours, dihydrotestosterone (D) 2 microg/kg BW/48 hours, E + P + D same doses, or solvent alone (CX). Ten other rats were sham-operated (SH) and used as controls. Animals were put in balance to determine Ca and phosphorus (Pi) intestinal apparent absorption (IA Ca, IA Pi) and urinary pyridinium crosslinks excretion. Plasma was collected for measurement of intact-parathyroid hormone (PTH), calcitonin (CT), insulin-like growth factor I (IGF-I), 1,25 dihydroxyvitamin D (1,25(OH)(2)D), Ca, and Pi. Orchidectomy induced marked seminal vesicles atrophy and increased plasma CT, PTH, and Ca concentrations. IA Ca was significantly higher in P rats, however, neither castration nor any other treatment had significant effects. Orchidectomy decreased femoral length, dry weight, and Ca content, whereas E or D given alone or together with P improved endochondral growth and enhanced femoral Ca content. Again, bone mineral density was lowered by orchidectomy and reestablished by both E and EPD, even above SH values, this effect being more important at the metaphyseal levels. Urinary pyridinium cross-links excretion and plasma osteocalcin concentrations were higher in the CX animals than in the controls. Although E and D given alone did reduce both biochemical turnover markers, they showed additive effect when given together (EPD). In conclusion, in the young castrated male rat, E was more efficient than D for preventing bone loss, the most important effect being induced by a combination of E+P+D.