Phytosterols in supplements containing Serenoa repens: an example of variability of active principles in commercial plant based products.

Phytosterols are one of the bioactive components responsible for the beneficial effects of Serenoa repens in Benign Prostate Hyperplasia. The aim of this study was to verify the actual variability of the phytosterols content in supplements containing serenoa, in order to provide useful elements to check the effectiveness of these preparations. The amount of campesterol, stigmasterol and ß-sitosterol were determined by gas-chromatography in commercial raw materials and supplements containing serenoa in association or not with other botanicals. The experimental data were used to calculate amounts of phytosterols for recommended daily dose. The overall results of this study show an extreme variability in the content and also in the amounts per daily dose of phytosterols of the examined supplements (both mono/multi components). These data confirm that the characterization of serenoa based supplements is insufficient to ensure comparable effects between different products.

Visceral fat adipocytes from obese and colorectal cancer subjects exhibit distinct secretory and ω6 polyunsaturated fatty acid profiles and deliver immunosuppressive signals to innate immunity cells.

Obesity is a low-grade chronic inflammatory state representing an important risk factor for colorectal cancer (CRC). Adipocytes strongly contribute to inflammation by producing inflammatory mediators. In this study we investigated the role of human visceral fat adipocytes in regulating the functions of innate immunity cells. Adipocyte-conditioned media (ACM) from obese (n = 14) and CRC (lean, n = 14; obese, n = 13) subjects released higher levels of pro-inflammatory/immunoregulatory factors as compared to ACM from healthy lean subjects (n = 13). Dendritic cells (DC), differentiated in the presence of ACM from obese and CRC subjects, expressed elevated levels of the inhibitory molecules PD-L1 and PD-L2, and showed a reduced IL-12/IL-10 ratio in response to both TLR ligand- and γδ T lymphocyte-induced maturation. Furthermore, CRC patient-derived ACM inhibited DC-mediated γδ T cell activation. The immunosuppressive signals delivered by ACM from obese and CRC individuals were associated with a pro-inflammatory secretory and ω6 polyunsaturated fatty acid profile of adipocytes. Interestingly, STAT3 activation in adipocytes correlated with dihomo-γlinolenic acid content and was further induced by arachidonic acid, which conversely down-modulated PPARγ. These results provide novel evidence for a cross-talk between human adipocytes and innate immunity cells whose alteration in obesity and CRC may lead to immune dysfunctions, thus setting the basis for cancer development.

ω3-PUFAs exert anti-inflammatory activity in visceral adipocytes from colorectal cancer patients.

OBJECTIVE: The aim of this study was to correlate specific fatty acid profiles of visceral white adipose tissue (WAT) with inflammatory signatures potentially associated with colorectal cancer (CRC). METHODS: Human adipocytes were isolated from biopsies of visceral WAT from 24 subjects subdivided in four groups: normal-weight (BMI 22.0-24.9 Kg/m2) and over-weight/obese (BMI 26.0-40.0 Kg/m2), affected or not by CRC. To define whether obesity and/or CRC affect the inflammatory status of WAT, the activation of the pro-inflammatory STAT3 and the anti-inflammatory PPARγ transcription factors as well as the expression of adiponectin were analyzed by immunoblotting in adipocytes isolated from each group of subjects. Furthermore, to evaluate whether differences in inflammatory WAT environment correlate with specific fatty acid profiles, gas-chromatographic analysis was carried out on WAT collected from all subject categories. Finally, the effect of the ω3 docosahexaenoic acid treatment on the balance between pro- and anti-inflammatory factors in adipocytes was also evaluated. RESULTS: We provide the first evidence for the existence of a pro-inflammatory environment in WAT of CRC patients, as assessed by the up-regulation of STAT3, and the concomitant decrease of PPARγ and adiponectin with respect to healthy subjects. WAT inflammatory status was independent of obesity degree but correlated with a decreased ω3-/ω6-polyunsaturated fatty acid ratio. These observations suggested that qualitative changes, other than quantitative ones, in WAT fatty acid may influence tissue dysfunctions potentially linked to inflammatory conditions. This hypothesis was further supported by the finding that adipocyte treatment with docosahexaenoic acid restored the equilibrium between STAT3 and PPARγ. CONCLUSION: Our results suggest that adipocyte dysfunctions occur in CRC patients creating a pro-inflammatory environment that might influence cancer development. Furthermore, the protective potential of docosahexaenoic acid in re-establishing the equilibrium between pro- and anti-inflammatory factors might represent a useful tool for preventive and therapeutic strategies.

Use of food supplements and determinants of usage in a sample Italian adult population.

OBJECTIVE: The aims were to collect data on consumption of different food supplements in a sample of the adult Italian population and to characterize users by demographic, physical and health-related characteristics, lifestyle and behaviour. DESIGN: Cross-sectional survey. SETTING: The study was conducted in 2008 in ten towns of Italy (two towns from each of the five macro-areas: Northwest, Northeast, Centre, South and Islands). SUBJECTS: Adults (n 10 000) aged ≥18 years were randomly selected and asked to fill in a self-administered questionnaire regarding their use of food supplements and the above variables. The effect of these variables on food supplement use was evaluated by univariate and multivariate logistic regression. RESULTS: Of the 1723 individuals who returned the questionnaire, 49% were users of food supplements. A large proportion (54%) of users used more than one category of food supplement: vitamin and/or mineral supplements were the most used (61%), followed by supplements with botanicals and botanical extracts (28%). The results obtained by logistic regression showed that gender, town size, education level, sports practice, regular use of wholemeal cereal-based foods and presence of a low stress level were determinants for the use of food supplements in the examined population. However, these determinants were not shared by all categories of supplements. CONCLUSIONS: The results of this preliminary study highlight that associations between demographic, dietary and lifestyle factors and use of different categories of food supplements differ according to products, and cannot be accounted for simply by dichotomizing individuals as users or non-users.

Reliability of a self-administered postal questionnaire on the use of food supplements in an italian adult population.

The objective of this study was to evaluate the reliability of a self-administered postal questionnaire on the use of food supplements. The study was carried out in subjects representative of an Italian adult population. Eight thousand eight hundred twenty-three subjects received the questionnaire; 1723 subjects completed it of which 102 twice (baseline and 1-month re-administration). The latter 204 questionnaires were used to test reliability using Cohen's kappa statistic (k) and the intra-class correlation coefficient (ICC) for categorical and quantitative variables, respectively. Subjects' characteristics such as sociodemographic and physical data, lifestyles, dietary habits, and most health characteristics showed very good agreement (ICC or k 1.00-0.55) between questionnaires, with the exception of answers about the consumption of some medicines (k 0.37-0.40). The reliability concerning the use of food supplements was satisfactory on the whole (k 0.69) and fairly satisfactory for different categories of food supplements (k 0.83-0.41). With regard to additional information about users of food supplements, the reliability of responses was fairly satisfactory on the whole (k 0.93-0.41), with some exceptions. The concordance/correlation coefficient values generally showed that the questionnaire is fairly reliable over the entire sample for collecting information on the use of food supplements.

Determination of alpha-amylase inhibitor activity of phaseolamin from kidney bean (Phaseolus vulgaris) in dietary supplements by HPAEC-PAD.

Some dietary supplements, so-called 'starch-blockers', used to control overweight, are based on the protein concentrate of the kidney bean, known to contain high levels of the alpha-amylase inhibitor phaseolamin, which may hinder the digestion of complex carbohydrates, thereby promoting or supporting weight loss. Currently, methods to determine the levels of alpha-amylase inhibitor are based on the measurement of alpha-amylase activity using colorimetric methods that cannot be applied to dietary supplements because they are complex mixtures of different ingredients that may interfere with the measurement. The aim of this study was to develop an alternative method to determine the level of phaseolamin in dietary supplements, using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) to measure the amount of maltose resulting from the action of the enzyme porcine alpha-amylase on soluble starch in the presence and absence of the inhibitor. The assay described proved sensitive and accurate for use with both dietary supplements and raw materials.

Effect of high intakes of fruit and vegetables on redox status in type 2 onset diabetes: a pilot study.

Evidence has accumulated indicating that oxidative stress may play a key role in the etiology of diabetic complications and the protective effects of antioxidant nutrients are a topic of intense research. The purpose of this study was both to obtain preliminary data on the effect of a diet high in fruit and vegetables on metabolic control and the oxidative status of patients with type 2 onset diabetes, and to identify the most useful biochemical parameters for future research. At the beginning of the study all subjects were asked to follow their usual diet and keep a seven-day food diary. Diabetic patients then received a dietary treatment designed to ensure a daily intake of 700-1000 g of fruit and vegetables; no dietary advice was given to controls. Dietary antioxidants, redox status markers, and parameters of metabolic control were measured in plasma and erythrocytes before and after the diet. Before following the diet, diabetic patients had lower levels of ascorbic acid, beta-carotene, and alpha-tocopherol/cholesterol ratio than controls. After the diet these parameters increased and there was also a reduction in total antioxidant capacity, uric acid, and malondialdehyde and a rise in reduced glutathione accompanied by a reduction in body mass index and cholesterol. In conclusion, a high consumption of fruit and vegetables by diabetic patients not receiving pharmacological treatment, seems to produce an improvement in some redox status parameters.

Influence of maternal protein intake on nitrogen fractions of human milk.

OBJECTIVES: Studies relating maternal diet to milk composition in humans have led to contradictory conclusions with regard to protein intake. The purpose of this paper was to examine if differences of protein intake in a group of lactating women can impact the protein and non-protein nitrogen fraction of their milk. SUBJECTS AND METHODS: Healthy lactating women(117) were recruited in Northern, Central, and Southern Italy. Their anthropometric measurements were obtained one month after delivery, while dietary evaluation was based on two consecutive 24-hour recalls. Infants' growth parameters were measured at birth and at one month. Milk collected at one month was analyzed for content of total nitrogen, protein nitrogen, non-protein nitrogen, and free amino acid profile. RESULTS: Maternal energy intakes were below the recommended values, while protein intakes were higher, with significant differences between geographical areas. There were no differences in the nitrogenous components of the milk examined with the exception of the non-protein nitrogen fraction and serine. Despite the different maternal intakes, no correlations were found between the mothers' parameters and milk components. CONCLUSION: This study shows that when protein requirements are met and there are no remarkable differences between intakes and requirements, there are no repercussions in nitrogen fractions.

Nutrient intake of Italian women during lactation.

OBJECTIVES: Very few data have been published concerning the actual energy and nutrient intakes of lactating women; in particular there have been no reports concerning Italian women. We report our findings on the energy and macronutrient intakes of a group of exclusively breast-feeding Italian women. Differences between the actual intakes and Italian Recommended Dietary Allowances are also discussed. SUBJECTS: Healthy lactating women aged 27-36 years were recruited in the three major geographical areas of Italy (North, Central, and South) METHODS: Dietary evaluation was based on two consecutive 24-hour recalls from each mother (dietary data, n = 125). Energy and nutrient intakes were estimated using a nutritional database. Statistical analysis was performed using parametric and non-parametric tests. RESULTS: Mean energy intakes for the whole country are below recommended values, while the protein intake, and the percentages of energy from fat and saturated fatty acids are higher than the recommended values. The amount of polyunsaturated fats is within the recommended intake. The percentage of energy from carbohydrates and the amount of fiber are lower than the recommended Italian levels. CONCLUSION: The results obtained in this sample of lactating women seem to point to a low energy intake associated with a moderate imbalance in the distribution of energy percentages from macronutrients.