Oxidative stress status in an institutionalised elderly group after the intake of a phenolic-rich dessert

Anthropometric, functional capacity, and oxidative stress changes in Brazilian community-living elderly subjects. A longitudinal study

OBJECTIVE

To examine the changes and relationships among anthropometric, functional and plasma oxidative stress markers in elderly.

DESIGN

longitudinal study.

SETTING

measurements in 2008 and 2010.

PARTICIPANTS

103 community-dwelling men and women aged 67-92.

MEASUREMENTS

Anthropometric parameters [waist, hip, arm and calf circumferences; waist-hip ratio, triceps skinfold thickness and others], basic (ADL) and instrumental activities of daily living (IADL)] and plasma oxidative stress markers (α-tocopherol, β-carotene and malondialdehyde) were assessed in 2008 and 2010.

RESULTS

ADL, IADL, body weight, skinfold thickness and circumferences of calf and arm decreased and waist and waist-hip ratio increased from 2008 to 2010. α-Tocopherol decreased and malondialdehyde plasma levels increased during the study period. In multiple logistic regression analyses, increased age (OR=1.12; IC: 1.02-1.23; p=0.02), female gender (OR=8.43; IC: 1.23-57.58; p=0.03), hypertension (OR=0.22; IC: 0.06-0.79; p=0.02), arthritis/arthrosis (OR=0.09; IC: 0.009-0.87; p=0.04) and depression (OR=0.20; IC: 0.04-1.03; p=0.05) were independent risk factors for functional decline.

CONCLUSION

Fat reduction, muscle loss, central obesity increase, functional decline and worsening of plasma oxidative stress were observed during 2-year follow-up. Some of the risk factors that were identified could be modified to help prevent functional decline in elderly. The factors deserving attention include hypertension, arthritis/arthrosis and depression.

Red Raspberries and Their Bioactive Polyphenols: Cardiometabolic and Neuronal Health Links

Diet is an essential factor that affects the risk of modern-day metabolic diseases, including cardiovascular disease, diabetes mellitus, obesity, and Alzheimer disease. The potential ability of certain foods and their bioactive compounds to reverse or prevent the progression of the pathogenic processes that underlie these diseases has attracted research attention. Red raspberries (Rubus idaeus L.) are unique berries with a rich history and nutrient and bioactive composition. They possess several essential micronutrients, dietary fibers, and polyphenolic components, especially ellagitannins and anthocyanins, the latter of which give them their distinctive red coloring. In vitro and in vivo studies have revealed various mechanisms through which anthocyanins and ellagitannins (via ellagic acid or their urolithin metabolites) and red raspberry extracts (or the entire fruit) could reduce the risk of or reverse metabolically associated pathophysiologies. To our knowledge, few studies in humans are available for evaluation. We review and summarize the available literature that assesses the health-promoting potential of red raspberries and select components in modulating metabolic disease risk, especially cardiovascular disease, diabetes mellitus, obesity, and Alzheimer disease-all of which share critical metabolic, oxidative, and inflammatory links. The body of research is growing and supports a potential role for red raspberries in reducing the risk of metabolically based chronic diseases.

Berries and oxidative stress markers: an overview of human intervention studies

Severalin vitroandin vivostudies have demonstrated that polyphenol-rich berries may counteract oxidative stress. In this review, we summarized the main finding from human intervention trials on the role of berries in the modulation of markers of oxidative lipid, protein and DNA damage.

In vitro and in vivo models of colorectal cancer: antigenotoxic activity of berries

The etiology of colorectal cancer (CRC), a common cause of cancer-related mortality globally, has strong associations with diet. There is considerable epidemiological evidence that fruits and vegetables are associated with reduced risk of CRC. This paper reviews the extensive evidence, both from in vitro studies and animal models, that components of berry fruits can modulate biomarkers of DNA damage and that these effects may be potentially chemoprotective, given the likely role that oxidative damage plays in mutation rate and cancer risk. Human intervention trials with berries are generally consistent in indicating a capacity to significantly decrease oxidative damage to DNA, but represent limited evidence for anticarcinogenicity, relying as they do on surrogate risk markers. To understand the effects of berry consumption on colorectal cancer risk, future studies will need to be well controlled, with defined berry extracts, using suitable and clinically relevant end points and considering the importance of the gut microbiota.

Dietary (poly)phenolics in human health: structures, bioavailability, and evidence of protective effects against chronic diseases

Human intervention trials have provided evidence for protective effects of various (poly)phenol-rich foods against chronic disease, including cardiovascular disease, neurodegeneration, and cancer. While there are considerable data suggesting benefits of (poly)phenol intake, conclusions regarding their preventive potential remain unresolved due to several limitations in existing studies. Bioactivity investigations using cell lines have made an extensive use of both (poly)phenolic aglycones and sugar conjugates, these being the typical forms that exist in planta, at concentrations in the low-μM-to-mM range. However, after ingestion, dietary (poly)phenolics appear in the circulatory system not as the parent compounds, but as phase II metabolites, and their presence in plasma after dietary intake rarely exceeds nM concentrations. Substantial quantities of both the parent compounds and their metabolites pass to the colon where they are degraded by the action of the local microbiota, giving rise principally to small phenolic acid and aromatic catabolites that are absorbed into the circulatory system. This comprehensive review describes the different groups of compounds that have been reported to be involved in human nutrition, their fate in the body as they pass through the gastrointestinal tract and are absorbed into the circulatory system, the evidence of their impact on human chronic diseases, and the possible mechanisms of action through which (poly)phenol metabolites and catabolites may exert these protective actions. It is concluded that better performed in vivo intervention and in vitro mechanistic studies are needed to fully understand how these molecules interact with human physiological and pathological processes.

A single portion of blueberry (Vaccinium corymbosum L) improves protection against DNA damage but not vascular function in healthy male volunteers

It has been suggested that anthocyanin-rich foods may exert antioxidant effects and improve vascular function as demonstrated mainly in vitro and in the animal model. Blueberries are rich sources of anthocyanins and we hypothesized that their intake could improve cell protection against oxidative stress and affect endothelial function in humans. The aim of the study was to investigate the effect of one portion (300 g) of blueberries on selected markers of oxidative stress and antioxidant protection (endogenous and oxidatively induced DNA damage) and of vascular function (changes in peripheral arterial tone and plasma nitric oxide levels) in male subjects. In a randomized cross-over design, separated by a wash out period ten young volunteers received one portion of blueberries ground by blender or one portion of a control jelly. Before and after consumption (at 1, 2, and 24 hours), blood samples were collected and used to evaluate anthocyanin absorption (through mass spectrometry), endogenous and H(2)O(2)-induced DNA damage in blood mononuclear cells (through the comet assay), and plasma nitric oxide concentrations (through a fluorometric assay). Peripheral arterial function was assessed by means of Endo-PAT 2000. Blueberries significantly reduced (P < .01) H(2)O(2)-induced DNA damage (-18%) 1 hour after blueberry consumption compared to control. No significant differences were observed for endogenous DNA damage, peripheral arterial function and nitric oxide levels after blueberry intake. In conclusion, one portion of blueberries seems sufficient to improve cell antioxidant defense against DNA damage, but further studies are necessary to understand their role on vascular function.

Raspberries and human health: a review

Dietary guidelines around the world recommend the increased consumption of fruits and vegetables as good sources of antioxidant phytochemicals for the prevention of chronic diseases. Red raspberries are a common and important fruit in the Western diet due to their content of essential nutrients and beneficial phytochemicals. Anthocyanins and ellagitannins are polyphenolic compounds and the major antioxidant phytochemicals present in raspberries. Whereas individual phytochemical constituents of raspberries have been studied for their biological activities, human intervention studies using whole berries are lacking in the literature. The nutritional and phytochemical compositions of red raspberries and their absorption, metabolism, and biological activity are reviewed. Finally, future directions of research are also identified.

Bioactivity and structure of biophenols as mediators of chronic diseases

Biophenols and their associated activity have generated intense interest. Current topics of debate are their bioavailability and bioactivity. It is generally assumed that their plasma concentrations are insufficient to produce the health benefits previously attributed to their consumption. However, data on localized in vivo concentrations are not available and many questions remain unanswered. Potential mechanisms by which they may exert significant bioactivity are discussed together with structure activity relationships. Biophenols are highly reactive species and they can react with a range of other compounds. Products of their reaction when functioning as antioxidants are examined.

Markers of oxidative DNA damage in human interventions with fruit and berries

Diets rich in fruit and vegetables are associated with a decreased risk of several cancers via numerous possible mechanisms. For example, phytochemicals may decrease oxidative DNA damage and enhance DNA repair. Markers of oxidative DNA damage in human dietary intervention trials used most frequently include oxidized nucleosides such as 7-hydro-8-oxo-2'-deoxyguanosine, which can be analyzed from isolated DNA or urine. Single-cell gel electrophoresis has been widely used to measure baseline or H2O2-induced DNA strand breaks or sites of modified bases sensitive to repair enzymes recognizing oxidized purines or pyrimidines. Recently, markers of DNA repair also have been used. Few controlled human dietary interventions have investigated the specific effects of fruit or berries. There are indications that kiwifruit can decrease H2O2 sensitivity of lymphocyte DNA ex vivo and enhance DNA repair. Carefully controlled studies with flavonoid-rich fruit or berry juices found only few significant differences; less rigorously controlled studies gave more optimistic results. Data on the effects of fruit and berries on DNA damage in humans are scarce and inconclusive; adequately controlled studies with validated markers are needed. Because levels of DNA damage are usually low in young healthy volunteers, groups with an enhanced risk of DNA damage should be studied.

Mitochondrial oxidative stress, aging and caloric restriction: the protein and methionine connection

Caloric restriction (CR) decreases aging rate and mitochondrial ROS (MitROS) production and oxidative stress in rat postmitotic tissues. Low levels of these parameters are also typical traits of long-lived mammals and birds. However, it is not known what dietary components are responsible for these changes during CR. It was recently observed that 40% protein restriction without strong CR also decreases MitROS generation and oxidative stress. This is interesting because protein restriction also increases maximum longevity (although to a lower extent than CR) and is a much more practicable intervention for humans than CR. Moreover, it was recently found that 80% methionine restriction substituting it for l-glutamate in the diet also decreases MitROS generation in rat liver. Thus, methionine restriction seems to be responsible for the decrease in ROS production observed in caloric restriction. This is interesting because it is known that exactly that procedure of methionine restriction also increases maximum longevity. Moreover, recent data show that methionine levels in tissue proteins negatively correlate with maximum longevity in mammals and birds. All these suggest that lowering of methionine levels is involved in the control of mitochondrial oxidative stress and vertebrate longevity by at least two different mechanisms: decreasing the sensitivity of proteins to oxidative damage, and lowering of the rate of ROS generation at mitochondria.