Unraveling the parahormetic mechanism underlying the health-protecting effects of grapeseed procyanidins

Proanthocyanidins (PACs), the predominant constituents within Grape Seed Extract (GSE), are intricate compounds composed of interconnected flavan-3-ol units. Renowned for their health-affirming properties, PACs offer a shield against a spectrum of inflammation associated diseases, such as diabetes, obesity, degenerations and possibly cancer. While monomeric and dimeric PACs undergo some absorption within the gastrointestinal tract, their larger oligomeric and polymeric counterparts are not bioavailable. However, higher molecular weight PACs engage with the colonic microbiota, fostering the production of bioavailable metabolites that undergo metabolic processes, culminating in the emergence of bioactive agents capable of modulating physiological processes. Within this investigation, a GSE enriched with polymeric PACs was employed to explore in detail their impact. Through comprehensive analysis, the present study unequivocally verified the gastrointestinal-mediated transformation of medium to high molecular weight polymeric PACs, thereby establishing the bioaccessibility of a principal catabolite termed 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (VL). Notably, our findings, encompassing cell biology, chemistry and proteomics, converge to the proposal of the notion of the capacity of VL to activate, upon oxidation to the corresponding quinone, the nuclear factor E2-related factor 2 (Nrf2) pathway-an intricate process that incites cellular defenses and mitigates stress-induced responses, such as a challenge brought by TNFα. This mechanistic paradigm seamlessly aligns with the concept of para-hormesis, ultimately orchestrating the resilience to stress and the preservation of cellular redox equilibrium and homeostasis as benchmarks of health.

Potential of dietary polyphenols for protection from age-related decline and neurodegeneration: a role for gut microbiota?

Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols - both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota.

Claimed effects, outcome variables and methods of measurement for health claims proposed under regulation (EC) 1924/2006 and related to cognitive function in adults

Some food/food components have been the object of request of authorization to the use of health claims related to cognitive function in adults and compliant with the Regulation (EC) 1924/2006. Most of the requests have received a negative opinion by the European Food Safety Authority (EFSA) also because of the choice of not appropriate outcome variables (OVs) and methods of measurement (MMs) selected in the trials used to substantiate the claim. This manuscript referes to the collection, collation and critical analysis of OVs and MMs related to cognitive function in adults. OVs and MMs were collected from the EFSA Guidance document and the applications for authorization of health claims pursuant to the Articles 13(5). The critical analysis of OVs and MMs, performed by a literature review, was aimed at defining their appropriateness in the context of a specific claimed effect. The results highlight the importance of an adequate choice of OVs and MMs for an effective substantiation of the claims related to cognitive functioning. The information provided in this document may serve to EFSA for updating the guidance on the scientific requirements for health claims related to cognitive functions, but also for a better design of randomized controlled trials aimed at substantiating such health claims.

Claimed effects, outcome variables and methods of measurement for health claims proposed under European Community Regulation 1924/2006 in the framework of protection against oxidative damage and cardiovascular health

BACKGROUND AND AIMS

The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006.

METHODS AND RESULTS

Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects.

CONCLUSIONS

The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims.

The use of new technologies for nutritional education in primary schools: a pilot study

INTRODUCTION

The aim of this study was evaluating if the presence of a humanoid robot could improve the efficacy of a game-based, nutritional education intervention.

STUDY DESIGN

This was a controlled, school-based pilot intervention carried out on fourth-grade school children (8-10 years old). A total of 112 children underwent a game-based nutritional educational lesson on the importance of carbohydrates. For one group (n = 58), the lesson was carried out by a nutritional educator, the Master of Taste (MT), whereas for another group, (n = 54) the Master of Taste was supported by a humanoid robot (MT + NAO). A third group of children (n = 33) served as control not receiving any lesson.

METHODS

The intervention efficacy was evaluated by questionnaires administered at the beginning and at the end of each intervention. The nutritional knowledge level was evaluated by the cultural-nutritional awareness factor (AF) score.

RESULTS

A total of 290 questionnaires were analyzed. Both MT and MT + NAO interventions significantly increased nutritional knowledge. At the end of the study, children in the MT and MT + NAO group showed similar AF scores, and the AF scores of both intervention groups were significantly higher than the AF score of the control group.

CONCLUSIONS

This study showed a significant increase in the nutritional knowledge of children involved in a game-based, single-lesson, educational intervention performed by a figure that has a background in food science. However, the presence of a humanoid robot to support this figure's teaching activity did not result in any significant learning improvement.

The β-cell burden index of food: A proposal

The quantity and quality of dietary fat and/or carbohydrate may alter one or more of the basic components of the insulin-glucose system, which in turn affect the pathways leading to alterations in glucose homeostasis and, possibly, to cardiovascular disease. This viewpoint article, reviewing some of the currently available tools aiming at quantifying the impact of dietary carbohydrates on the glucose-insulin homeostatic loop, highlights the unmet need of a more thorough assessment of the complex interaction between dietary factors and the glucose-insulin system. A novel index, the "β-cell burden index", may turn out to be a valuable tool to quantify the role played by the diet in shaping the risk of type 2 diabetes, cardiovascular disease and other metabolic and degenerative disorders, ideally orienting their prevention with strategies based on dietary modifications.

Glycemic index and glycemic load of commercial Italian foods

BACKGROUND AND AIM

The glycemic index (GI) and glycemic load (GL) are useful parameters in the nutritional classification of carbohydrate foods. Diets characterized by a low GI and/or a low GL have been repeatedly and independently associated with decreased risk of diabetes and other chronic diseases. The aim of this study is to report the GI and GL value of carbohydrate-rich foods available on the Italian market and mostly consumed in Italy.

METHODS AND RESULTS

GI values were determined according to FAO/WHO (1997) and ISO (2010). Overall, the 141 commercial foods that were analyzed represent food categories that are the source of >80% carbohydrate intake in Italy. The food items chosen were based mainly on the market share of the brand within each food category and grouped into 13 food categories: 1) beverages: fermented milk drink, juice, smoothie, soft drink; 2) biscuits; 3) breads; 4) bread substitutes; 5) breakfast cereals; 6) cakes and snacks; 7) candy and confectionery; 8) cereals; 9) desserts and ice-creams; 10) marmalade and jam; 11) pasta; 12) pizza; 13) sugar and sweetener.

CONCLUSION

This database of commercial Italian foods partly overcomes the lack of information on GI and GL of local foods, contributing to a better understanding of the association between GI/GL and health and providing a more informed choice to Italian consumers and health practitioners.

Assessment of vascular and endothelial dysfunction in nutritional studies

Vascular and endothelial dysfunction (VED) is emerging as a potential set of early markers of cardiovascular disease risk and tests for its measurement have been widely used in clinical research. The aim of this viewpoint is to describe and discuss the current usage of these measures in well-designed nutritional trials, using the potential relationship between fruit juice intake and VED as example. A search was conducted using the NHS evidence portal including studies published in English between January 1980 and October 2013. Only 10 suitable studies were selected, which investigated the effect of fruit juice intake on VED, among which 4 interventions used flow-mediated dilatation, 2 arterial stiffness, 2 a combination of arterial stiffness and flow-mediated dilatation, 2 carotid intimal media thickness and 1 iontophoresis with laser Doppler. Despite minimal effects reported on classical CVD markers, such as lipids, 8 out of the 10 identified studies reported an effect on endothelial function following juice consumption, indicating that VED tests can be effectively used in human dietary interventions to identify relationships between bioactive compounds from fruit and CVD risk. However, paucity of available data, scarcity of compound bioavailability and metabolism information, strong heterogeneity among experimental methodologies and a number of limitations to study designs, still limit the interpretation of the results obtained through these measures. Future, well-designed studies with greater attention to consider use of VED measures are needed to strengthen the utility of VED tests in nutrition research such as those investigating the impact of polyphenol-rich juices and CVD risk.

Bioaccumulation of resveratrol metabolites in myocardial tissue is dose-time dependent and related to cardiac hemodynamics in diabetic rats

BACKGROUND AND AIMS

Trans-resveratrol (RSV) is a natural compound occurring in different foods and plants, which in vivo is rapidly conjugated with glucuronic acid and sulfate. Despite its demonstrated cardioprotective activity, the bioaccumulation of RSV or its metabolites in cardiac tissue is still unknown.

METHODS AND RESULTS

Diabetic rats were randomized to 1, 3 or 6 weeks of RSV treatment at two different doses (1 or 5 mg/kg/day). A dose and time-dependent accumulation was observed, with no detectable levels of RSV metabolites found in heart tissues after 1 week and significant concentrations of RSV-3-sulfate and RSV-3-glucuronide after 6 weeks of treatment (0.05 nmol/g of tissue and 0.01 nmol/g of tissue, respectively). Tissue accumulation of RSV metabolites was accompanied by an improvement of cardiac function in long-term diabetes, when myocardial morpho-functional damage is more evident, with an almost complete recovery of all hemodynamic parameters, at the highest RSV dose.

CONCLUSION

Even if a higher concentration of RSV in tissues cannot be ruled out after constant oral administration, an accumulation coherent with what is usually evaluated in cell based mechanistic studies is largely unattainable and the RSV unconjugated form would not be present in this paradigm. The current investigation provides data on myocardial tissue concentrations of RSV metabolites, after short/medium term RSV treatment. This knowledge constitutes a basic requirement for future studies aimed at reliably defining the molecular pathways underlying RSV-mediated cardioprotective effects and opens up new perspectives for research focused on testing phenolic compounds as adjuvants in degenerative heart diseases.

Anti-estrogenic activity of a human resveratrol metabolite

BACKGROUND AND AIMS

Resveratrol, the most investigated dietary compound in studies aimed at linking wine consumption to human health, is an extremely minor component of this beverage and it is generally studied in vitro as the unconjugated aglycone at concentrations largely exceeding those found in the human circulatory system after dietary intake. Moreover, following intestinal absorption, trans-resveratrol and its glucoside, which are naturally present in wine and other food sources, are converted to sulphate and glucuronide metabolites. An estrogenic activity has previously been documented for resveratrol, yet nothing is known about the activity of its blood-circulating metabolic derivatives.

METHODS AND RESULTS

Using a yeast two-hybrid detection system relying on the interaction between the ligand-binding domain of the human oestrogen receptors α and β and the human coactivator Tif2, we have systematically examined the oestrogen agonist and antagonist activities of the two main resveratrol forms present in planta (trans-resveratrol and trans-resveratrol-3-O-glucoside) and of the three main metabolites found in human plasma (trans-resveratrol-3-O-sulphate, trans-resveratrol-3-O-glucuronide and trans-resveratrol-4'-O-glucuronide). Only resveratrol-3-O-sulphate was found to display a fairly strong and oestrogen receptor α-preferential antagonistic activity, which was confirmed in a human breast adenocarcinoma cell line containing a luciferase reporter gene under the control of an oestrogen-responsive promoter.

CONCLUSIONS

We show, for the first time, that resveratrol-3-O-sulphate, but neither of its metabolites, is endowed with anti-estrogenic activity and how human metabolism of phenolic substances plays a pivotal role in modulating their biological effect.

Macrophage polarization: the answer to the diet/inflammation conundrum?

Macrophages, a heterogeneous and ubiquitous cell population representing up to 15% of the cellular content of different types of tissue, are the principal cell mediators in response to pathogens, inflammation process, tissue homeostasis and repair and play a pivotal role in atherosclerosis and insulin resistance because of their capacity to be the major source of inflammatory cytokines, which can function through paracrine and endocrine mechanisms. Recently, differently activated macrophage populations have been described, depending on a large variety of microenvironmental signals, and it is now recognized that their activation plays a crucial role in the development and progression of atherosclerosis. There is good evidence of the ability of conjugated linoleic acids and polyphenolic compounds to modulate inflammation in experimental models involving macrophages. This observation leaves room to the intriguing hypothesis that macrophage polarization could represent one of the unifying mechanisms through which specific food components can exert anti-inflammatory effects in humans, contributing to the prevention of chronic diseases strongly linked to inflammation, such as atherosclerosis. Future studies should be addressed to substantiate this hypothesis, investigating whether or not physiological concentrations of food-derived metabolites can perturb macrophage activation in vitro. On the in vivo side, the evaluation of macrophage populations in tissues, however complex, should be included among the analyses performed in observational and intervention studies, in order to understand if macrophage activation is involved in the anti-inflammatory activity of a specific dietary regimen.

Food selection based on high total antioxidant capacity improves endothelial function in a low cardiovascular risk population

BACKGROUND AND AIMS

Oxidative stress has been advocated as a major cause for cardiovascular disease (CVD), and low plasma antioxidant concentrations are associated with endothelial dysfunction, the first step towards atherosclerosis. However, although the antioxidant content in fruits and vegetables may explain at least in part their protective effect against CVD, supplementation with antioxidant vitamins fails to improve endothelial function and reduce CVD risk. The aim of this study was to investigate the impact of a diet rich in antioxidants on endothelial function measured by flow-mediated dilatation (FMD) in volunteers at low cardiovascular risk.

METHODS AND RESULTS

In a crossover trial, 24 subjects (13 women, mean age 61 ± 3 years), received, in a randomised order, a 14-day high (HT) and a 14-day low (LT) antioxidant diets, with a 2-week wash-out (WO) in between. Both diets were comparable in daily portions of fruits and vegetables, and in alcohol, fibre and macronutrient intake, but differed in their total antioxidant capacity. Before and after each diet, anthropometrics, blood pressure, fasting plasma glucose, lipid profile, hepatic enzymes, circulating antioxidant concentrations, high sensitivity C-reactive protein (hs-CRP) and FMD were assessed. FMD increased significantly during the HT diet compared to the LT (p < 0.000). FMD values were 2.3% higher after HT compared with LT (p < 0.001) after adjustment for age, gender and diet order. α-tocopherol increased significantly (p < 0.05) and hs-CRP and of γ-glutamyltranspeptidase decreased significantly (p < 0.05 and p < 0.01, respectively) during the HT diet, compared with the LT diet.

CONCLUSIONS

A short-term HT diet improves endothelial function in volunteers at low cardiovascular risk, which may further reduce their risk of CVD.

The effect of breakfasts varying in glycemic index and glycemic load on dietary induced thermogenesis and respiratory quotient

BACKGROUND AND AIM

Glycemic index (GI) and Glycemic Load (GL) are parameters of carbohydrate bioavailability able to influence risk of chronic diseases. GL can be lowered either by reducing carbohydrate intake or by reducing the GI of the carbohydrate moiety of a mixed meal. These two approaches might have a different impact on Dietary-Induced Thermogenesis (DIT) and preferential substrate oxidation in the postprandial period, which are variables known to be involved in the regulation of body weight and body composition. This dietary, crossover intervention trial was designed to evaluate the effect on DIT and Respiratory Quotient (RQ) of three isocaloric breakfasts different in GI and/or GL (high GI and high GL [HGI-HGL] vs. low GI and low GL [LGI-LGL]; vs. high GI and low GL [HGI-LGL]) followed by a standard meal.

METHODS AND RESULTS

RQ and DIT were measured in 16 lean young males by indirect calorimetry for 8h. DIT resulted significantly higher after the LGI-LGL compared to the HGI-HGL breakfast (p<0.05). Postprandial changes in RQ differed among all breakfasts (p<0.001). RQ increased from baseline after the two breakfasts with highest carbohydrate content and significantly more after the HGI-HGL than after the LGI-LGL (p<0.02), whereas it decreased after the HGI-LGL breakfast, which contained a higher amount of fat.

CONCLUSIONS

Reducing the GL of a meal by reducing GI seems an effective strategy to increase energy expenditure while maintaining a good rate of lipid oxidation. This might be related to different profiles of postprandial hormones affecting substrate oxidation.

Polyphenols and health: what compounds are involved?

On the basis of prospective, cross-sectional and intervention studies linking polyphenols to human health, several experimental papers in the literature have tried to evaluate the molecular mechanisms involved in their bioactivity. Polyphenols are reported to in vitro inhibit cancer cell proliferation, reduce vascularisation, protect neurons, stimulate vasodilation and improve insulin secretion, but are often studied as aglycones or as sugar conjugates and at non-physiological concentration. However, it is now well established that polyphenols undergo substantial metabolism after being ingested by humans in dietary relevant amount and that concentrations of plasma metabolites after a normal dietary intake rarely exceed nmol/L. This viewpoint intends to highlight that uncritical judgements made on the basis of the published literature, particularly about toxicity and bioactivity, may sometimes have been misled and misleading and to conclude that i) bioavailability values reported in the literature for phenolic compounds should be strongly reconsidered in the light of the large number of newly identified circulating and excreted metabolites, with particular attention to colonic ring-fission products which are obviously contributing much more than expected to the percentage of their absorption; ii) it is phenolic metabolites, formed in the small intestine and hepatic cells, and low molecular weight catabolic products of the colonic microflora to travel around the human body in the circulatory system or reach body tissues to elicit bioactive effects. Understanding these compounds certainly carries interest for drug-discovery but also for dietary prevention of disease.

Intake of the plant lignans matairesinol, secoisolariciresinol, pinoresinol, and lariciresinol in relation to vascular inflammation and endothelial dysfunction in middle age-elderly men and post-menopausal women living in Northern Italy

BACKGROUND AND AIMS

It has been suggested that lignan intake may decrease the risk for cardiovascular disease (CVD) by modifying traditional risk factors as well as aortic stiffness. However, the role of dietary lignans on the vascular system is largely unknown. The objective was to investigate whether dietary intake of plant lignans in a free-living population was associated with markers of vascular inflammation and function.

METHODS AND RESULTS

We performed a cross-sectional study in 242 (151 males) men and post-menopausal women. Anthropometric characteristics and lignan intake were evaluated. Soluble intercellular adhesion molecule-1 (sICAM-1), insulin, high-sensitive C-reactive protein, glucose, total cholesterol, HDL-cholesterol and triacylglycerols were measured in fasting blood samples. Brachial flow-mediated dilation (FMD) measurements were available for 101 subjects (56 males). Median (interquartile range) daily intake of matairesinol (MAT), secoisolariciresinol (SECO), pinoresinol (PINO), lariciresinol (LARI), and total lignans was 20.9 microg (17.4), 335.3 microg (289.1), 96.7 microg (91.1), 175.7 microg (135.8), and 665.5 microg (413.7), respectively, as assessed by 3-day weighed food record. Plasma concentrations of sICAM-1 (whole sample) significantly decreased (mean (95%CI) = 358 microg/L (320-401), 276 microg/L (252-303), 298 microg/L (271-326), and 269 microg/L (239-303), P per trend 0.013) and FMD values (FMD sub-group) significantly increased (4.1% (2.2-6.0), 5.7% (4.3-7.2), 6.4% (4.9-7.8), and 8.1% (6.3-10.0), P per trend 0.016) across quartiles of energy-adjusted MAT intake, even after adjustment for relevant clinical and dietary variables. Intake of SECO was also inversely related to plasma sICAM-1 (P per trend 0.018), but not to FMD values. No relationship between intake of PINO, LARI or total lignans and either sICAM-1 or FMD values was observed.

CONCLUSIONS

Higher MAT intakes in the context of a typical Northern Italian diet are associated to lower vascular inflammation and endothelial dysfunction, which could have some implications in CVD prevention.

The total antioxidant capacity of the diet is an independent predictor of plasma beta-carotene

OBJECTIVE

To investigate the contribution of the total antioxidant capacity (TAC) of the diet to plasma concentrations of beta-carotene.

DESIGN

Cross-sectional study.

SETTING

Department of Public Health and Department of Internal Medicine and Biomedical Sciences, University of Parma.

SUBJECTS

A total of 247 apparently healthy adult men (n=140) and women (n=107).

METHODS

A medical history, a physical exam including height, weight, waist circumference and blood pressure measurements, a fasting blood draw, an oral glucose tolerance test and a 3-day food record.

RESULTS

We observe a negative trend across quartiles of plasma beta-carotene for most biological variables clustering in the insulin resistance syndrome, as well as for traditional and new risk factors for type II diabetes and cardiovascular disease (CVD), including C-reactive protein and gamma-glutamyltranspeptidase (P<0.05). Regarding dietary characteristics, energy-adjusted intake of fat, fiber, fruits, vegetables, beta-carotene, vitamin C, vitamin E and dietary TAC significantly increased with increasing plasma beta-carotene (P<0.05), whereas alcohol intake decreased (P=0.013). Adjusted geometric means (95% confidence interval) of plasma beta-carotene significantly increased across quartiles of dietary TAC, even when single dietary antioxidants were considered in the model (QI=0.087 mg/dl (0.073-0.102); QII=0.087 mg/dl (0.075-0.103); QIII=0.114 mg/dl (0.098-0.132) and QIV=0.110 mg/dl (0.093-0.130); P for linear trend=0.026). When the population was divided on the basis of alcohol consumption, this trend was also observed in subjects drinking <20 g alcohol/day (P=0.034), but not in those with higher alcohol intake (P=0.448).

CONCLUSIONS

Dietary TAC is an independent predictor of plasma beta-carotene, especially in moderate alcohol drinkers. This may explain, at least in part, the inverse relationship observed between plasma beta-carotene and risk of chronic diseases associated to high levels of oxidative stress (i.e., diabetes and CVD), as well as the failure of beta-carotene supplements alone in reducing such risk.

A fluorescence-based method for the detection of adhesive properties of lactic acid bacteria to Caco-2 cells

AIMS

The ability of probiotic micro-organisms to adhere to the intestinal surface is regarded as a substantial advantage in terms of bacteria persistence in the gastrointestinal tract. The aim of the present study was the development of a method based on fluorescent staining of bacteria and subsequent spectrofluorimetric detection to quantify the adhesion of several strains of Lactobacillus and Bifidobacterium to Caco-2 cells.

METHODS AND RESULTS

Lactic acid bacteria strains were subjected to fluorescent staining using the viable probe carboxyfluorescein diacetate and subsequently incubated on Caco-2 monolayers. The adhesion of the micro-organisms was determined by spectrofluorimetry following the lysis of the attached bacterial cells and expressed as adhesion percentage. The values obtained for the micro-organisms tested ranged from 4% for Bifidobacterium infantis Bi1 to 10% for a Bifidobacterium mixture containing three different strains.

CONCLUSIONS

In the present study we successfully applied fluorescent labelling and fluorimetric detection to investigate the adhesive properties of some Lactobacillus and Bifidobacterium strains and a Bifidobacterium mixture to Caco-2 cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results proved that fluorescent labelling is suitable for adhesion studies and provides a reliable and safer alternative to radioactive labelling.

Selected methodologies to assess oxidative/antioxidant status in vivo: a critical review

AIM

This review is intended to be a critical analysis of selected red-ox methodologies aimed at understanding why the biomarker might be valuable and how it can be measured, highlighting any pitfalls and sample interferences, and describing specific cases of application.

DATA SUMMARY

Over recent years, considerable efforts have been made to identify and validate the markers of the oxidative/antioxidant status of the human body.

CONCLUSION

Different assays must be applied simultaneously and the related information merged in order to obtain a clearer picture of red-ox status. The relevance of the markers needs to be understood in both pathological and physiological terms: more information is needed about how these markers are regulated in human beings and how they are associated with the diet, because improving health and well-being is as important as preventing the risks of disease itself.

Experience with a new gastrostomy-jejunal feeding tube

Many patients in need of long-term feeding by tube enterostomy have neurologic or mechanical deficits that increase their risk for aspiration. To reduce this risk, a combined gastrostomy-jejunal tube has been developed. This tube permits gastric decompression while the formula is being delivered into the jejunum. The use of this tube has been evaluated in 45 patients. There were three (7%) major complications and two (4%) postoperative deaths. The deaths did not appear to be directly related to the insertion of the tube. There was no clinical evidence of aspiration. This tube can be used to deliver postoperative and long-term enteral nutrition with minimal rates of morbidity and mortality.