Effect of dark chocolate on plasma epicatechin levels, DNA resistance to oxidative stress and total antioxidant activity in healthy subjects.

Dark chocolate (DC) may be cardioprotective by antioxidant properties of flavonoids. We investigated the effect of DC (860 mg polyphenols, of which 58 mg epicatechin) compared with white chocolate (WC; 5 mg polyphenols, undetectable epicatechin) on plasma epicatechin levels, mononuclear blood cells (MNBC) DNA damage and plasma total antioxidant activity (TAA). Twenty healthy subjects followed a balanced diet (55 % of energy from carbohydrates, 30 % from fat and 1 g protein/kg body weight) for 4 weeks. Since the 14th day until the 27th day, they introduced daily 45 g of either WC (n 10) or DC (n 10). Whole experimental period was standardised in antioxidant intake. Blood samples were collected at T(0), after 2 weeks (T(14)), 2 h and 22 h after the first chocolate intake (T(14+2 h) and T(14+22 h)), and at 27th day, before chocolate intake (T(27)), 2 h and 22 h after (T(27+2 h) and T(27+22 h)). Samples, except for T(14+2 h) and T(27+2 h), were fasting collected. Detectable epicatechin levels were observed exclusively 2 h after DC intake (T(14+2 h) = 0.362 (se 0.052) micromol/l and T(27+2 h) = 0.369 (se 0.041) micromol/l); at the same times corresponded lower MNBC DNA damages (T(14+2 h) = - 19.4 (se 3.4) % v. T(14), P < 0.05; T(27+2 h) = - 24 (se 7.4) % v. T(27), P < 0.05; T(14+2 h) v. T(27+2 h), P = 0.7). Both effects were no longer evident after 22 h. No effect was observed on TAA. WC did not affect any variable. DC may transiently improve DNA resistance to oxidative stress, probably for flavonoid kinetics.

Nutritional counselling in disabled people: effects on dietary patterns, body composition and cardiovascular risk factors.

AIM: Disabled persons are frequently affected by nutritional status impairment, consequent to quantitative and qualitative inadequacy of diet and physical inactivity, resulting in a significant reduction of fat-free mass and bone mineral density (BMD), and an over-expression of fat mass and an increased number of biochemical risk factors for chronic degenerative diseases. The aim of this study was to analyse the applicability and the efficacy of a nutritional counselling intervention in order to improve dietary intake and nutritional status in disabled people. METHODS: Thirty-seven disabled subjects (24 with physical disability and 13 with both mental retardation and physical disability; age 33.5+/-9.2 years) underwent an assessment of nutritional status, and an intervention with nutritional counselling was proposed to each patient for one year. Anthropometric measurements, indirect calorimetry, dual-energy X-ray absorptiometry, dietary intake, and biochemical analysis at baseline (T0) and after one year (T1) of counselling intervention were performed. RESULTS: Sixty-five percent of patients dropped out. Overall, no significant improvement in cardiovascular risk factors, body composition and dietary patterns was reported at T1 in completer subjects. Six subjects who were obese or overweight at T0, reported significant weight and fat mass (FM) reduction at T1 (P=0.01 and P=0.00, respectively). CONCLUSION: Nutritional counselling seems to be ineffective and poorly applicable to disabled people. Further studies should be directed towards a treatment program associated with careful screening, motivation analysis, and follow-up in this patient population.

Poor agreement between a portable armband and indirect calorimetry in the assessment of resting energy expenditure.

BACKGROUND & AIMS: To evaluate the agreement between resting energy expenditure (REE) estimated by a portable armband and measured by indirect calorimetry. METHODS: One-hundred and twenty-seven women and 42 men with a mean (SD) age of 44 (12) years and a body mass index of 30.2 (5.4) kg/m(2) were studied. REE was estimated using the Sense Wear Pro 2 Armband (SWA), measured using the Sensor Medics 29 metabolic cart (V(max)), and estimated using Schofield's equation. The limits of agreement (LOA) and the concordance correlation coefficient (CCC) were used to evaluate the interchangeability of the methods. RESULTS: The LOA between REE(SWA) and REE(Vmax) were wide in both women (-269 to 378 kcal/day) and men (-330 to 545 kcal/day) and CCC was low (0.579 in females and 0.583 in males, p<0.0001 for both). REE(Schofield) agreed with REE(Vmax) to a similar degree (CCC=0.563 in females and 0.500 in males, p<0.0001 for both). CONCLUSIONS: SWA and indirect calorimetry are not interchangeable methods for the assessment of REE in normal-weight and obese subjects.

Circulating salicylic acid is related to fruit and vegetable consumption in healthy subjects.

Salicylic acid (SA) is a natural phenolic compound known as the active principle of aspirin. Its presence in vegetal sources suggests that fruit and vegetable (FV) consumption could produce measurable SA serum concentrations in human subjects not taking aspirin. The aim of this study was to investigate the relationship between FV intake and circulating SA in healthy subjects. Thirty-eight volunteers (twenty-two males and sixteen females) were recruited from an Italian university campus. They recorded their food intake for 7 d to evaluate dietary consumption and, in particular, FV intake; fasting blood samples were taken on the morning of the eighth day to measure SA serum concentration, using a sensitive stable isotope dilution and GC-MS method. Median SA serum concentration was 0.124 mumol/l (range 0.028-0.295). Circulating SA was significantly related to FV consumption, both to the mean daily intake (r2 0.13, P = 0.03) and to the last day intake (r2 0.16, P = 0.01). The subjects in the highest FV intake quartile in the preceding day (>4.75 servings) had significantly higher SA concentrations than in the lowest quartile ( < 2.3 servings) (median concentrations 0.188 and 0.112 mumol/l, respectively; P = 0.04). This study proved that, after overnight fast, human subjects not taking aspirin display circulating SA in amounts related to the FV consumption. It is therefore possible that the beneficial effects of regular FV consumption in man could also depend on low chronic SA exposure.

Measurement of salicylic acid in human serum using stable isotope dilution and gas chromatography-mass spectrometry.

A simple, highly selective, and sensitive method using stable isotope dilution and gas chromatography-mass spectrometry has been developed to quantify salicylic acid (SA) at concentrations naturally occurring in biological fluids, such as in the serum of subjects not taking aspirin. After extraction of liquid-liquid with diethyl ether and ethyl acetate and preparation of the tert-butyldimethylsilyl derivative, SA content was detected using deuterated SA as internal standard. The mean recovery of SA from serum was 85 +/- 6%. Intra- and interday precision and % relative error were <15% in all cases. With a detection limit of 0.6 ng and a quantification limit of 2 ng, the method is therefore also adequate for population studies because of the small amount of blood necessary to perform the analyses.

Comparison between daidzein and genistein antioxidant activity in primary and cancer lymphocytes.

The main objective of this study was to compare the protective effect of daidzein and genistein against induced oxidative damage in Jurkat T-cell line and in peripheral blood lymphocytes of healthy subjects. After supplementation of cells with isoflavones (from 2.5 to 20micromol/L in Jurkat T-cell and from 0.01 to 2.5micromol/L in primary lymphocytes, 24h), we determined DNA damage induced by hydrogen peroxide using the comet assay and lipid peroxidation evaluating malondialdehyde (MDA) production after ferrous ion treatment. Supplementation of Jurkat cells and primary lymphocytes with both isoflavones significantly increased DNA protection from oxidative damage at concentrations between 0.1 and 5micromol/L (P<0.05), and with just daidzein, at concentrations higher than 2.5micromol/L, there was a decrease in the production of MDA (P<0.05). Our results seem to support that daidzein is just as effective as genistein in protecting cells against oxidative damage especially with respect to DNA. Moreover, since the protective effect was found at concentrations reachable in plasma after soy consumption (less than 2micromol/L), it can be assumed that the antioxidant activity of isoflavones could really contribute to the healthy properties of soy.