Antioxidant status and risk of cancer in the SU.VI.MAX study: is the effect of supplementation dependent on baseline levels?

The SUpplementation en VItamines et Mineraux AntioXydants (SU.VI.MAX) study, a randomised double-blind, primary-prevention trial showed that after 7.5 years, low-dose antioxidant supplementation lowered the total cancer incidence in men, but not in women. To explain this difference in the impact of antioxidant supplementation in men and women, we hypothesised that the effect of supplementation is dependent on initial antioxidant status; 12 741 French adults (7713 females aged 35--60 years; 5028 males aged 45--60 years) received daily antioxidant supplementation (120 mg vitamin C, 30 mg vitamin E, 6 mg beta-carotene, 100 microg Se, 20 mg Zn daily) or a matching placebo. Cut-off limits for baseline serum concentrations of the different antioxidant vitamins and minerals were defined as follows for both men and women: 0.3 micromol/l for beta-carotene, 11.4 micromol/l for vitamin C, 15 micromol/l for vitamin E, 0.75 micromol/l for Se and 10.7 micromol/l for Zn. The percentage of men with serum concentrations under cut-off limits was higher for vitamins C and E and beta-carotene in those who developed a cancer than in those who did not. The risk of cancer was higher in men with baseline concentrations of serum vitamin C or vitamin E under cut-off limits, but not in women. The effect of supplementation was greater in men with baseline serum concentrations of vitamin C, vitamin E and beta-carotene below the cut-off limits compared with those above it. This effect was maintained only for vitamin E after adjustment for age, tobacco, and alcohol consumption and BMI. No effect of supplementation could be seen in women. Baseline antioxidant status is related to the risk of cancer in men but not in women and therefore does not entirely explain the differences observed in the effect of antioxidant supplementation on cancer risk between sexes in the SU.VI.MAX study.     

Serum selenium determinants in French adults: the SU.VI.M.AX study

The objective of the present work was to assess the relationship between serum Se concentrations and environmental determinants (i.e. lifestyle, social activity, geographic region, urban status, education, familial status, physical activity, BMI, tobacco, and food and alcohol consumption). Baseline results from 13 017 subjects (7876 women aged 35-60 and 5141 men aged 45-60) who participated in the SU.VI.M.AX (Supplémentation en Vitamines et Minéraux Antioxydants) study were analysed. Fewer than 2 % of the volunteers had a serum Se status under 0.75 micromol/l, which has been quoted as the cut-off of biological Se sub-deficiency. Women had significantly lower serum Se concentrations than men (1.09 (sd 0.19) micromol/l (n 7423) and 1.14 (sd 0.20) micromol/l (n 4915), P<0.0001, respectively). Significant differences in serum Se concentrations were observed between geographic areas. In both sexes, the serum Se concentration increased with alcohol, meat and fish consumption, and decreased with smoking. In premenopausal women, the serum Se concentration was higher in contraceptive-pill users than in non-users. In women only, age was associated with increased serum Se concentrations, and obesity (BMI> or =30 kg/m2) was associated with decreased serum Se levels. In men, we observed a decrease in serum Se concentrations with increased consumption of vegetables and fruits. In conclusion, though few of the volunteers participating in the SU.VI.M.AX study had Se status in the sub-deficiency range, 83 % of women and 75 % of men had serum concentrations below the value considered optimal for glutathione peroxidase activity. The largest Se associations in both sexes were found with regions, smoking, alcohol, meat and fish consumption. Further studies are needed to understand the difference in Se status between genders.     

Consommation d’huiles et matières grasses en France : relations avec le niveau d’étude et la région de résidence dans la cohorte SU.VI.MAX

The relationships between intake of added oils and fats with region of residence and educational level were also assessed. Our objective was to describe the relative contribution of ten created food groups to total fat intake in middle-aged subjects.Subjects were participants of the SU.VI.MAX study who completed at least six 24-h dietary records after inclusion into the study (n=6572).Added oils and fats were the main source of total fat intake. Animal fat (AF) and margarine intakes showed a significant inverse association with educational level, whereas oils with mono-unsaturated fatty acids (MUFA) were positively associated with education level. AF intake was significantly higher in the Western and Northern parts of France (54.2 and 50.4%) and lower in the Mediterranean Coast (39.0%). A significant inverse gradient was found with oils with poly-unsaturated fatty acids (PUFA) or MUFA in the Southwest and the Mediterranean Coast compared to the Northern part of France.We showed a north to south gradient for animal fat intake and the opposite for oils with MUFA and PUFA in France This gradient parallels the known disparities for cardiovascular mortality in this country. This should contribute to adapt dietary guidelines for dietary change in a public-health perspective.     

Niveaux d’apport et sources alimentaires des principaux acides gras polyinsaturés n-6 et n-3 dans la population adulte en France*

The intake of individual n-6 and n-3 polyunsaturated fatty acids (PUFA) have been estimated in 4,884 adult subjects of both sexes, volunteers from the French SUVIMAX intervention trial. On an energy basis, both men and women consumed 4.2% energy as linoleic acid, 0.38% as α-linolenic acid, 0.08% as arachidonic acid, 0.06% as eicosapentaenoic acid (EPA), 0.03% as docosapentaenoic acid (DPA) and 0.11% as docosahexaenoic acid (DHA), with a mean linoleic/α-linolenic acid ratio of 11.3. The intake of α-linolenic acid was well below the current recommendations (0.8% of energy) for almost all subjects, as a consequence of the low consumption of α-linolenic acid-rich oils and fats. The mean intake levels of long-chain n-3 PUFA were higher than the recommended levels, but showed great interindividual variations, due to very large differences in the consumption of fish, especially of fatty fish.     

Beneficial effect of pentoxifylline on microvesicular steatotic livers submitted to a prolonged cold ischemia

BACKGROUND: The deleterious effect of steatosis on transplanted livers is mainly related to a microcirculation impairment. We investigated the effect of preservation duration on the recovery of isolated perfused rat steatotic livers and tested the effect of pentoxifylline (PTX), known to have a beneficial effect on hepatic microcirculation. MATERIALS AND METHODS: Fatty rat livers were obtained using a diet able to induce an 80% to 100% microvesicular steatosis within 7 days. We studied the effect of the duration of preservation (12 hr, 18 hr, and 24 hr) on fatty and normal isolated perfused rat liver. PTX was added to University of Wisconsin solution during cold storage (30 mM/kg of weight) and at reperfusion (3 mM) (n=5 livers in each group). Lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, bile production, and vascular resistance were evaluated. The liver injury at the end of perfusion was assessed by optical and electron microscopy. RESULTS: For a 24-hr preservation period, fatty livers demonstrated increased enzymatic release (aspartate aminotransferase: 42+/-16 vs. 17+/-5 IU/L/g of liver, P<0.005; alanine aminotransferase: 32+/-13 vs. 13+/-3 IU/L/g of liver, P<0.005; lactate dehydrogenase: 1,207+/-497 vs. 291+/-195 IU/L/g of liver, P<0.001). Vascular resistance (0.32 vs. 0.15 cm H(2)O/min/mL, P<0.0005) and bile output (67+/-24 vs. 141+/-61 mg/g of liver, P<0.05) were decreased. Peliosis appeared after an 18-hr preservation period for fatty livers compared with a 24-hr preservation period for controls. All these negative effects were suppressed by PTX. CONCLUSION: Diffuse microvesicular steatosis became deleterious only after long preservation times (24 hr). PTX prevented this effect.     

The use of computerised 24 h dietary recalls in the French SU.VI.MAX Study: number of recalls required

OBJECTIVE: The 24 h dietary recall is a widely used method to estimate nutritional intakes in epidemiological studies. The objective of the present study was to estimate the number of recalls necessary for an accurate estimation of nutrient intake in French adults followed for 4 y. SUBJECTS AND METHODS: Participants of the SU.VI.MAX study (intervention study on the effects of antioxidant supplementation on chronic diseases) who completed a 24 h dietary recall every 2 months for at least 1 y. Inter- and intra-individual variance ratios (S(w)/S(b)) were calculated by analysis of variance for two time periods: year 1 and 2 (n=4955) and year 3 and 4 (n=1458). The number of recalls necessary was calculated using an accuracy of 0.9. RESULTS: The highest intra-individual/inter-individual variance ratio in the first period was seen for beta-carotene and the lowest for carbohydrate. The number of recalls necessary was five for carbohydrate and calcium intake and 16 for beta-carotene. For proteins, total and saturated fat, fibre, vitamin C and iron eight recalls were required, while nine, 11 and 10 recalls were necessary for mono- and polyunsaturated fat and vitamin E, respectively. The variance ratios in the second period were all lower and fewer recalls were therefore required. The same difference in number of recalls required between the two time periods was observed when only those subjects were included who completed at least 18 recalls (n=727). CONCLUSION: These results indicate that for an accurate estimation of carbohydrate intake only, already five recalls are necessary. Fewer recalls may be needed during long-time follow-up. SPONSORSHIP: The SU.VI.MAX Study has support from public and private sectors: Fruit d'Or Recherche, Candia, Lipton, Kellogg's, Céréal, CERIN, Estée Lauder, L'Oréal, Peugeot, Jet Service, RP Scherer, Sodexho, France Telecom, Santogen, Becton Dickinson, Fould Springer, Boehringer Diagnostic, Seppic Givaudan Lavirotte, Le grand Canal, Danone and Knorr.     

Malignant pheochromocytoma: new malignancy criteria

Purpose  

The pathological diagnosis of malignancy in pheochromocytomas remains a controversial issue. According to the WHO, malignancy is defined in the presence of metastasis. Multiparameter scoring systems such as PASS (Pheochromocytoma of Adrenal gland Scaled Score) have been used but remain controversial. The aim of this study was to search for new immunohistologic elements allowing determination of pheochromocytoma malignancy.