Quantitative trait loci mapping of polyphenol metabolites from a 'Latham' x 'Glen Moy' red raspberry (Rubus idaeus L) cross.

OBJECTIVE: The objective of this study was to investigate the genetic control of polyphenol accumulation in red raspberry (Rubus idaeus L). METHODS: The levels of total anthocyanins and 37 individual polyphenol metabolites were measured over three years in a raspberry biparental mapping population. Quantitative trait loci (QTLs) for these traits were mapped onto a high-density SNP linkage map. RESULTS: At least one QTL was detected for each trait, with good consistency among the years. On four linkage groups (LG), there were major QTLs affecting several metabolites. On LG1, a QTL had large effects on anthocyanins and flavonols containing a rutinoside or rhamnose group. On LG4, a QTL had large effects on several flavonols and on LG5 and LG6 QTLs had large effects on ellagic acid derivatives. Smaller QTLs were found on LG2 and LG3. CONCLUSION: The identification of robust QTLs for key polyphenols in raspberry provides great potential for marker-assisted breeding for improved levels of potentially health beneficial components.

The impact of blackcurrant juice on attention, mood and brain wave spectral activity in young healthy volunteers.

There is a growing body of evidence from randomized controlled trials which indicates that consumption of berries has a positive effect upon the cognitive function of healthy adults. It has been recommended that studies combining cognitive and physiological measures be undertaken in order to strengthen the evidence base for the putative effects of flavonoid consumption on cognitive outcomes. This pilot study utilized a randomized, double-blind and placebo controlled crossover design to assess the influence of the acute administration of anthocyanin-rich blackcurrant juice, standardized at 500 mg of polyphenols, on mood and attention. Additionally, this trial used electroencephalography (EEG) to assess if any changes in cognitive performance are associated with changes in localized prefrontal cortex neuronal activity in nine healthy young adults. Outcomes from the pilot EEG data highlight an anxiolytic effect of the consumption of a single serve blackcurrant juice, as indexed by a suppression of α spectral power, and an increase in the slow wave δ and θ spectral powers. There was also an indication of greater alertness and lower fatigue, as indexed by an increase in ß power and suppression of α spectral power. Outcomes from the CogTrack™ system indicated a small acute increase in reaction times during the digit vigilance task.

Antioxidant Rich Potato Improves Arterial Stiffness in Healthy Adults.

Arterial stiffness is an emerging risk factor for cardiovascular disease and dietary anthocyanins may be important in mediating vascular tone. The present study investigated the effect of consumption of an anthocyanin-rich potato, Purple Majesty on arterial stiffness measured as pulse wave velocity in 14 healthy male and female adults. Participants consumed 200 g/day of cooked purple potato containing 288 mg anthocyanins, or a white potato containing negligible anthocyanins for 14 days, separated by a 7-day washout period. Non-invasive assessment of vascular tone by pulse wave velocity was determined in addition to systolic and diastolic blood pressure, high-density lipoproteins, low-density lipoproteins, triglycerides, glucose, insulin and C-reactive protein. Pulse wave velocity was significantly reduced (p = 0.001) following Purple Majesty consumption for 14-days. There were no significant changes with any other clinical parameter measured, and no changes following white potato consumption. The findings from this short-term study indicate a potential effect of Purple Majesty consumption on arterial stiffness.

In Vitro Models for Studying Secondary Plant Metabolite Digestion and Bioaccessibility.

There is an increased interest in secondary plant metabolites, such as polyphenols and carotenoids, due to their proposed health benefits. Much attention has focused on their bioavailability, a prerequisite for further physiological functions. As human studies are time consuming, costly, and restricted by ethical concerns, in vitro models for investigating the effects of digestion on these compounds have been developed and employed to predict their release from the food matrix, bioaccessibility, and assess changes in their profiles prior to absorption. Most typically, models simulate digestion in the oral cavity, the stomach, the small intestine, and, occasionally, the large intestine. A plethora of models have been reported, the choice mostly driven by the type of phytochemical studied, whether the purpose is screening or studying under close physiological conditions, and the availability of the model systems. Unfortunately, the diversity of model conditions has hampered the ability to compare results across different studies. For example, there is substantial variability in the time of digestion, concentrations of salts, enzymes, and bile acids used, pH, the inclusion of various digestion stages; and whether chosen conditions are static (with fixed concentrations of enzymes, bile salts, digesta, and so on) or dynamic (varying concentrations of these constituents). This review presents an overview of models that have been employed to study the digestion of both lipophilic and hydrophilic phytochemicals, comparing digestive conditions in vitro and in vivo and, finally, suggests a set of parameters for static models that resemble physiological conditions.

Differential effectiveness of berry polyphenols as anti-giardial agents.

Following previous work on the anti-giardial effect of blueberry polyphenols, a range of polyphenol-rich extracts from berries and other fruits was screened for their ability to kill Giardia duodenalis, an intestinal parasite of humans. Polyphenol-rich extracts were prepared from berries using solid-phase extraction and applied to trophozoites of Giardia duodenalis grown in vitro. All berry extracts caused inhibition at 166 µg gallic acid equivalents (GAE)/ml phenol content but extracts from strawberry, arctic bramble, blackberry and cloudberry were as effective as the currently used drug, metronidazole, causing complete trophozoite mortality in vitro. Cloudberry extracts were found to be the most effective causing effectively complete trophozoite mortality at 66 µg GAE/ml. The polyphenol composition of the more effective berry extracts suggested that the presence of ellagitannins could be an important factor. However, the potency of cloudberry could be related to high ellagitannin content but also to the presence of substantial amounts of unconjugated p-coumaric acid and benzoic acid. These in vitro effects occur at concentrations easily achievable in the gut after berry ingestion and we discuss the likelihood that berry extracts could be effective anti-giardial agents in vivo.

Polyphenols journey through blood-brain barrier towards neuronal protection.

Age-related complications such as neurodegenerative disorders are increasing and remain cureless. The possibility of altering the progression or the development of these multifactorial diseases through diet is an emerging and attractive approach with increasing experimental support. We examined the potential of known bioavailable phenolic sulfates, arising from colonic metabolism of berries, to influence hallmarks of neurodegenerative processes. In silico predictions and in vitro transport studies across blood-brain barrier (BBB) endothelial cells, at circulating concentrations, provided evidence for differential transport, likely related to chemical structure. Moreover, endothelial metabolism of these phenolic sulfates produced a plethora of novel chemical entities with further potential bioactivies. Pre-conditioning with phenolic sulfates improved cellular responses to oxidative, excitotoxicity and inflammatory injuries and this attenuation of neuroinflammation was achieved via modulation of NF-κB pathway. Our results support the hypothesis that these small molecules, derived from dietary (poly)phenols may cross the BBB, reach brain cells, modulate microglia-mediated inflammation and exert neuroprotective effects, with potential for alleviation of neurodegenerative diseases.

Salal (Gaultheria shallon) and aronia (Aronia melanocarpa) fruits from Orkney: Phenolic content, composition and effect of wine-making.

The polyphenol content and composition of salal and aronia fruits from plants established in Orkney was examined. The composition of the salal fruits has not previously been recorded, and they contained anthocyanins, flavonols, hydroxycinnamates and proanthocyanins. The aronia fruits contained anthocyanins, hydroxycinnamates and flavonols as previously described. Although salal fruits had half the anthocyanin content of aronia fruits, salal wine had higher anthocyanin content, probably due to the relative stability of diglycoside pentose anthocyanins. The wines contained components suggestive of anthocyanin and flavonol degradation, but there was no consistent pattern to stability within phenolic sub-classes. Indeed, the wine made from equal amounts of salal and aronia fruits had patterns of recovery of individual phenolic components which could not be predicted from recoveries in wines from single fruits. This strongly suggests that stability of individual phenolic constituents during wine-making is influenced by the presence and relative stability of other components.

Anthocyanins from red wine--their stability under simulated gastrointestinal digestion.

The stability of anthocyanins from red wine was assessed using an in vitro digestion system that simulated the physiochemical changes that occur in the upper gastrointestinal tract. Anthocyanins in red wine were stable to gastric conditions whereas there was a small loss in total phenol content. After pancreatic digestion, the total anthocyanins were very poorly recovered compared to the bulk phenols in the IN sample, which was previously described as the "serum-available" fraction, and the majority of the anthocyanins and phenols were recovered in the OUT fraction, previously described as the "colon-available" fraction. Removing alcohol from the wine samples prior to the procedure did not markedly affect this pattern. The composition of anthocyanins in the post gastric, IN and OUT samples was analysed using liquid chromatography mass-spectrometry. The red wine used contained over 20 identifiable anthocyanins of which the main components were 3-O-glucosides of malvidin, peonidin, petundin, delphidin and cyanidin. Coumaroylated-glucoside derivatives of malvidin, petundin, peonidin, and delphinidin were observed and acetylated glucosides of peonidin, petundin and malvidin were also identified. Anthocyanins with modified aglycones similar to vitisin A derivatives of delphinidin, peonidin, petunidin and malvidin were also identified. After the in vitro digestion procedure, only five anthocyanins could be detected in the IN (serum-available) and the OUT (colon-available) fractions, which were confirmed as malvidin-3-O-glucoside and the vitisin A adducts of malvidin-3-O-glucoside, malvidin-3-O-acetylglucoside, malvidin-3-O-coumaroylglucoside and peonidin-3-O-glucoside. Malvidin-3-O-glucoside was recovered at 0.2% in the IN fraction and 0.9% in the OUT fraction. However, the vitisin derivatives were much more stable to pancreatic digestion. Assuming that the vitisin A derivatives display similar biological properties to their parent anthocyanins, their enhanced gastrointestinal stability could lead to enhanced bioavailability and bio-effectiveness in vivo.

Cell-wall proteins from Sitka spruce xylem are selectively insolubilised during formation of dehydrogenation polymers of coniferyl alcohol.

Extracts from the lignifying xylem of Sitka spruce that were enriched in cell-wall-associated glycoproteins contained peroxidase and oxidase activity and readily formed lignin-like water-insoluble dehydrogenation polymers (DHPs) from coniferyl alcohol (CA) when supplied with H2O2. During the formation of DHPs, the abundance of a number of polypeptides in the extracts was diminished. However, these polypeptides were also diminished in control reactions that contained H2O2 but lacked CA. Polypeptides could be recovered from the DHPs by heating in SDS-PAGE sample buffer but no insolubilised polypeptides could be recovered from the + H2O2 reactions. Although most of the DHP-bound polypeptides were easily removed by pre-washing the DHPs, two polypeptides at 125 and 52 kDa remained tightly bound to the DHPs. The abundance of the two DHP-bound polypeptides mirrored the diminution of 120 and 46 kDa polypeptides in the extracts. The N-terminal protein sequences of the 125 and 52 kDa DHP-bound polypeptides were essentially identical to the sequences obtained from the 120 and 46 kDa polypeptides from the extracts, which confirmed that the DHP-bound polypeptides were derived from these soluble polypeptides. The 125-kDa DHP-bound polypeptide yielded an N-terminal protein sequence that was identical to a laccase-type oxidase previously identified in similar extracts from lignifying Sitka xylem. The N-terminal protein sequence of the 46-kDa polypeptide was homologous with a subset of plant peroxidases. The DHPs had tightly bound peroxidase and oxidase activity, which suggested that these polypeptides were active in their insolubilised state. The mechanism and selectivity of insolubilisation of these enzymes is discussed.

Purification and analysis of growth-regulating xyloglucan-derived oligosaccharides by high-pressure liquid chromatography.

The retention times of 10 oligosaccharides, generated from the xyloglucans of Rosa and Tropaeolum by the action of Trichoderma cellulase, and of 17 related carbohydrates, in h.p.l.c. on an amino-substituted silica (Amino-Spheri-5) depended largely on the number of hydroxyl groups per molecule, whereas h.p.l.c. on a pellicular anion-exchange resin (CarboPac PA1) was strongly influenced by the nature of the sugar residues present, especially L-fucose, and by their linkages. The major nonasaccharide (XG9, D-Glc4-D-Xyl3-D-Gal-L-Fuc) obtained from Rosa xyloglucan, after purification on Amino-Spheri-5, retained biological activity as an inhibitor of auxin-induced growth in a Pisum stem-segment bioassay. H.p.l.c. on Amino-Spheri-5 was used to monitor the action of "Driselase" in stripping the non-reducing terminal alpha-D-Xylp-(1----6)-beta-D-Glcp units from XG9 to yield a pentasaccharide (XG5, D-Glc2-D-Xyl-D-Gal-L-Fuc).

Oxidase activity in lignifying xylem of a taxonomically diverse range of trees: identification of a conifer laccase.

In a diverse taxonomic range of tree species, including representative species of ancient families of angiosperms (Magnolia x soulangiana Soul.-Bod.) and gymnosperms (Ginkgo biloba L.), oxidase activity was associated with cell walls of developing xylem and was enriched in extracts of cell wall-associated glycoproteins. In all species where oxidase activity was detected histochemically, it was expressed in cell walls of lignifying, differentiating xylem cells and was absent from old wood, cambium and phloem, suggesting that oxidases have a conservative role in lignification of tree xylem. An oxidase from the developing xylem of Picea sitchensis (Bong) Carr. (Sitka spruce) was partially purified by a combination of lectin affinity and immobilized metal ion affinity chromatography. A portion of the total oxidase activity had high affinity for immobilized zinc ions and this feature allowed it to be separated from the bulk of oxidase activity. Two polypeptides that could have been responsible for the bound oxidase activity were enriched by this procedure. The smaller polypeptide of Mr approximately 73 kDa yielded an N-terminal amino-acid sequence that was homologous to laccase-like polyphenol oxidases (E.C. 1.10.3.2) from loblolly pine (Pinus taeda L.), poplar (Populus euramericana (Dode) Guinier) and Arabidopsis. The larger polypeptide (Mr approximately 77 kDa) yielded an N-terminal amino-acid sequence that was homologous with a range of plant subtilisin-like serine proteinases. The roles of oxidase and proteinase activities in developing xylem are discussed.

Recruiting African Americans into research on cognitive aging.

A total of 218 adults with an average age of seventy-eight years participated in a study of memory performance in community elders. A computer-generated random zip code list of adults > or = 70 years of age was purchased and a four-phase telephone-screening plan was adopted. During the second year, the sampling plan had to be changed, with a convenience-sampling plan being adopted to recruit adequate numbers of African-American subjects. Fifty-seven percent of the African-American subjects (N = 55) and 68% of the White subjects (N = 83) were recruited from random sampling methods. As compared to the random sample, the convenience sample was significantly older (80 vs 76), had more depression (12 vs 9), had lower physical functioning (46 vs 65), and less vitality (48 vs 60). On meta-memory, the convenience sample scored higher than the random sample on achievement (3.84 vs 3.69), and lower on task (3.75 vs 3.85). The convenience sample scored significantly lower than the random sample on memory performance (15 vs 18), and memory self-efficacy (26 vs 33). More research is needed to document normative measures for cognitive function and to facilitate accurate comparisons between African-American elderly and other elderly.

Cognitive interventions among older adults.

This chapter reviews psychoeducational and/or psychosocial interventions designed to improve cognitive function in adults without cognitive impairment. Included are sections on (a) meta-analyses and other reviews; (b) cognitive aging and cognitive improvement; (c) memory training; (d) depression and memory improvement; (e) self-efficacy and aging memory; (f) maintenance of gains and subject retention; (g) comprehensive memory improvement program; and (h) future research. Several aspects of memory training now known to influence outcomes, i.e., memory performance, need to be considered in future studies. First, follow-up instruction (booster sessions) facilitates the use of these newly learned memory strategies in elders' everyday lives. Second, elders' memory self-efficacy (beliefs and confidence) impacts performance. Third, the inclusion of subjective measures in memory training is recommended. Fourth, greater emphasis needs to be placed on the modification of participants' attitudes toward aging-related memory loss. Fifth, designs must emphasize the long-term outcomes of the memory training. Sixth, establishing a relationship between a memory intervention and functional ability (IADLs) is the next step in assisting older adults to remain independent. If early failure in cognitive ability can be improved through intervention, perhaps early decline in functional independence and the need for formal services, e.g., nursing home placement, can be delayed.

Memory strategies used by cognitively intact and cognitively impaired older adults.

This study examined the influence of depression and health on the use of memory strategies of cognitively impaired (n = 55) and cognitively intact (n = 169) older adults. The intact group used memory strategies more often than the impaired group and were more likely to use external strategies such as diaries, notes, and lists, instead of internal strategies such as elaboration and rehearsal. The impaired group used the internal strategies such as elaboration and rehearsal. The impaired group used the internal strategy effort more often. There was no difference in perception of memory capacity between groups. Depression had a negative influence on perceptions of capacity and change in both groups.

Predictors of the use of memory improvement strategies by older adults.

This study examined the ability of depression, health, and memory self-efficacy scores to predict the use of internal and external memory strategies by cognitively impaired and cognitively intact older adults. There were no differences between the groups on memory self-efficacy scores and on the extent of their use of the external memory strategy of place. The cognitively intact group used strategies to aid memory more often than did the cognitively impaired group and used more external than internal memory strategies. The cognitively intact group used the internal strategies of elaboration and rehearsal more often than the other group and were less likely to expend effort than the other group. Memory self-efficacy scores were the sole predictor of use of external memory aids by the cognitively intact group, and age was the sole predictor of use of external memory aids by the cognitively impaired group. No variable was able to predict the use of internal memory strategies by either group.

A review of screening instruments for assessing cognition and mental status in older adults.

Older adults in non-psychiatric acute and long-term care settings need to be screened routinely for cognitive function and mental status by clinicians and health care providers. Screening instruments increasingly are being used in order to evaluate programs, implement clinical decisions and conduct research. The purpose, scope and depth of needed assessment guides the selection of the screening instrument. This article critically reviews 11 screening instruments used to assess cognitive function and mental status in older adults: Dementia of the Alzheimer Type Inventory, Brief Cognitive Rating Scale, Blessed Dementia Scale, Cognitive Capacity Screening Examination, Cognitive Levels Scale, FROMAJE, Global Deterioration Scale, Mini-Mental State Exam, Clinical Dementia Rating, Mental Status Questionnaire and the Short Portable Mental Status Questionnaire. Since cognitive impairment is a broad construct, the descriptors used to search the literature were the following: age-associated memory impairment, acute confusional states, Alzheimer's disease, cognition, confusion, delirium, dementia, mental status, multi-infarct dementia, Pick's disease, primary degenerative dementia, pseudodementia and senile dementia of the Alzheimer's type. The Brief Cognitive Rating Scale and the Dementia of the Alzheimer Type Inventory are the only two instruments capable of distinguishing Alzheimer's from other dementias, and the CDR is the only instrument that assesses hobbies.

In vitro protective effects of colon-available extract of Camellia sinensis (tea) against hydrogen peroxide and beta-amyloid (Aß((1-42))) induced cytotoxicity in differentiated PC12 cells.

There is mounting evidence that the deposition and aggregation of ß-amyloid peptides (Aß) in the brain play a significant role in the development and pathogenesis of Alzheimer's disease. There is further evidence that free radical species such as hydrogen peroxide (H(2)O(2)) mediate Aß induced toxicity. Previous studies have demonstrated that green tea polyphenols possess neuroprotective properties through their ability to ameliorate oxidative stress induced by free radical species. Green tea polyphenols have also been shown to enhance cognition in various animal models of induced cognitive impairment. Upon ingestion, green tea polyphenols are metabolised and undergo bio-transformation which affects their bioavailability and therefore efficacy. In this study, a green tea extract was subjected to a simulated gastrointestinal digestion and a 'colon-available' extract (CAGTE) prepared and assessed for its potential protective effects against H(2)O(2) and Aß((1-42)) induced cytotoxicity using differentiated PC12 cells (dPC12) as a model for neuronal cells. CAGTE represents green tea phytochemicals potentially available after upper gastrointestinal digestion. CAGTE which was depleted in flavan-3-ols, as shown by LC-MS analysis, protected dPC12 cells at concentration ranges of 0.3-10 µg/ml and 0.03-0.125 µg/ml for H(2)O(2) and Aß((1-42)), induced cytotoxicity, respectively. At high concentrations, CAGTE exhibited direct anti-proliferative effects, in line with the reputed anti-cancer properties of green tea polyphenols. These results demonstrate that potentially bioavailable green tea metabolites are able to ameliorate both H(2)O(2) and Aß((1-42)) induced cytotoxicity.

Assessing the influence of genotype and temperature on polyphenol composition in cloudberry (Rubus chamaemorus L.) using a novel mass spectrometric method.

A high-throughput abbreviated liquid chromatography mass spectrometric (ACMS) method was used to assess the relative influence of genotype and temperature on polyphenol composition in cloudberries. Principal component analysis (PCA) plots of the collated ACMS data showed a separation between crosses based on their female parents (Nyby or Fjellgull). Crosses with Nyby as the female parent had higher relative levels of masses assignable to certain ellagitannin derivatives. Crosses with Fjellgull had higher levels of distinctive masses assignable to quercetin derivatives (including a hydroxy-3-methylglutaroyl hexose derivative not previously identified in cloudberry) and anthocyanin derivatives. There was also a separation between samples grown at lower and higher temperatures, which was driven by m/z signals associated with ellagitannins and notably a major component, sanguiin H-6. Therefore, abbreviated MS techniques can discern genetic and/or environmental influences in polyphenol composition and can quickly assess quality in breeding programmes or in response to environmental changes.