The Effects of Berry Extracts on Oxidative Stress in Cultured Cardiomyocytes and Microglial Cells: A Potential Cardioprotective and Neuroprotective Mechanism.

Oxidative stress is a key underlying factor in cognitive decline and atherosclerosis. Oxidative stress occurs at the cellular level with an imbalance between reactive oxygen species and reactive nitrogen species and a deficiency in antioxidants. Mounting evidence suggests that berry flavonoids may promote cellular health by exerting antioxidant properties. Black currant and various berry extracts were tested in microglia (BV-2) and cardiomyocyte (HL-1) cell lines to study their biological effects. The principal ingredients in black currant and cranberry extract-delphinidin 3-rutinoside (D3R) and cyanidin 3-glucoside (C3G), were also assessed. A menadione-induced oxidative stressor was used, and its output was quantified to detect oxidative stress (CellROXTM). Black currant extract had similar antioxidant effects as N-acetylcysteine (NAC) in HL-1 cells with regard to cellular protection, whereas cranberry extract was ineffective. In contrast, cranberry extract was comparable in effectiveness to black currant extract in BV-2 cells. D3R and C3G also reduced oxidative stress similarly to whole berry extracts, which indicates that these ingredients may confer the antioxidant effects of berries. Black currant and cranberry extracts inhibit oxidative stress in microglial and cardiomyocyte cell lines. Black currant extract was more effective in reducing oxidative stress in the HL-1 cells, whereas cranberry extract was comparable in reducing oxidative stress in the BV-2 cells. The results suggest that berry flavonoids exert neuro- and cardioprotective effects.

A select review reporting the quality of studies measuring endothelial dysfunction in randomised diet intervention trials.

A quality assessment of the primary studies reported in the literature carried out using select dietary ingredients (DI) purported to affect vascular endothelial function was conducted through a systematic PubMed search from January 2000 to August 2012. A total of seventy randomised controlled trials with defined DI (folic acid (fifteen), n-3 fatty acids (twenty), cocoa (fifteen) and isoflavones (twenty)) and standardised measures of vascular endothelial function were evaluated. Jadad scores, quality scoring parameters for DI and flow-mediated dilation (FMD) methodology used were ascertained. A total of 3959 randomised subjects, mean age 51 (se 0·21) years (range 9-79 years), were represented in the dataset. The mean Jadad scores did not differ statistically among the DI studies, with the majority of the studies being of good quality. Higher DI quality scores were achieved by studies using the botanical ingredients cocoa and isoflavones than by those using the nutrient ingredients folic acid and n-3 fatty acids. The mean DI quality scores were 4·13 (se 0·34), 5·20 (se 0·47), 6·13 (se 0·41) and 6·00 (se 0·59) for the folic acid, n-3 fatty acid, cocoa and isoflavone intervention studies, respectively (and significantly different). The mean Corretti FMD scores were 7·27 (se 0·56), 7·46 (se 0·79), 6·29 (se 0·61) and 7·11 (se 0·56) for the folic acid, n-3 fatty acid, cocoa and isoflavone intervention studies, respectively (NS). FMD studies failed to adequately describe the equipment used and more than half failed to provide an adequate description of the procedures used for vascular image acquisition and measurement. DI can be utilised for dietary intervention studies; however, the methodology should be clearly reported using the guidelines for assessment for both DI and FMD.

Considerations for Optimizing Warfighter Psychological Health with a Research-Based Flavonoid Approach: A Review.

Optimal nutrition is imperative for psychological health. Oxidative stress and inflammation are underlying etiologies for alterations in psychological health. Warfighters are at risk of health concerns such as depression due to increased stress in austere environments and family separation while deployed. Over the last decade, research has demonstrated the health benefits of flavonoids found in fruits and berries. Berry flavonoids have potent antioxidant and anti-inflammatory properties by inhibiting oxidative stress and inflammation. In this review, the promising effects of various berries rich in bioactive flavonoids are examined. By inhibiting oxidative stress, berry flavonoids have the potential to modulate brain, cardiovascular, and intestinal health. There is a critical need for targeted interventions to address psychological health concerns within the warfighter population, and a berry flavonoid-rich diet and/or berry flavonoid dietary supplement intervention may prove beneficial as an adjunctive therapy. Structured searches of the literature were performed in the PubMed, CINAHL, and EMBASE databases using predetermined keywords. This review focuses on berry flavonoids' critical and fundamental bioactive properties and their potential effects on psychological health in investigations utilizing cell, animal, and human model systems.

Adequacy of early enteral nutrition in adult patients in the intensive care unit.

AIMS AND OBJECTIVES: To evaluate the adequacy of energy and protein intake of patients in a Korean intensive care unit in the first four days after initiation of enteral feeding and to investigate the factors that had impact on adequate intake. BACKGROUND: Underfeeding is a common problem for patients hospitalised in the intensive care unit and is associated with severe negative consequences, including increased morbidity and mortality. DESIGN: A prospective, cohort study was conducted in a medical intensive care unit of a university hospital in Korea. METHODS: A total of 34 adult patients who had a primary medical diagnosis and who had received bolus enteral nutrition for the first four days after initiation of enteral nutrition were enrolled in this study. The data on prescription and intake of energy and protein, feeding method and feeding interruption were recorded during the first four days after enteral feeding initiation. Underfeeding was defined as the intake <90% of required energy and protein. RESULTS: Most patients (62%) received insufficient energy, although some (29%) received adequate energy. More than half of patients (56%) had insufficient protein intake during the first four days after enteral feeding was initiated. Logistic regression analysis showed that the factors associated with underfeeding of energy were early initiation of enteral nutrition, under-prescription of energy and prolonged interruption of prescribed enteral nutrition. CONCLUSION: Underfeeding is frequent in Korean critically ill patients owing to early initiation, under-prescription and prolonged interruption of enteral feeding. RELEVANCE TO CLINICAL PRACTICE: Interventions need to be developed and tested that address early initiation, under-prescription and prolonged interruption of enteral nutrition. Findings from this study are important as they form the foundation for the development of evidence-based care that is badly needed to eliminate underfeeding in this large vulnerable Korean intensive care unit population.

The emerging role of flavonoid-rich cocoa and chocolate in cardiovascular health and disease.

Cocoa and chocolate have recently been found to be rich plant-derived sources of antioxidant flavonoids with beneficial cardiovascular properties. These favorable physiological effects include: antioxidant activity, vasodilation and blood pressure reduction, inhibition of platelet activity, and decreased inflammation. Increasing evidence from experimental and clinical studies using cocoa-derived products and chocolate suggest an important role for these high-flavanol-containing foods in heart and vascular protection.

Antioxidant vitamins C and E improve endothelial function in children with hyperlipidemia: Endothelial Assessment of Risk from Lipids in Youth (EARLY) Trial.

BACKGROUND: Hyperlipidemia is associated with endothelial dysfunction, an early event in atherosclerosis and predictor of risk for future coronary artery disease. Epidemiological studies suggest that increased dietary intake of antioxidants reduces the risk of coronary artery disease. The purpose of this study was to determine whether antioxidant vitamin therapy improves endothelial function and affects surrogate biomarkers for oxidative stress and inflammation in hyperlipidemic children. METHODS AND RESULTS: In a randomized, double-blind, placebo-controlled trial, the effects of antioxidant vitamins C (500 mg/d) and E (400 IU/d) for 6 weeks and the National Cholesterol Education Program Step II (NCEP-II) diet for 6 months on endothelium-dependent flow-mediated dilation (FMD) of the brachial artery were examined in 15 children with familial hypercholesterolemia (FH) or the phenotype of familial combined hyperlipidemia (FCH). Antioxidant vitamin therapy improved FMD of the brachial artery compared with baseline (P<0.001) without an effect on biomarkers for oxidative stress (autoantibodies to epitopes of oxidized LDL, F2-isoprostanes, 8-hydroxy-2'-deoxyguanosine), inflammation (C-reactive protein), or levels of asymmetric dimethylarginine, an endogenous inhibitor of nitric oxide. CONCLUSIONS: Antioxidant therapy with vitamins C and E restores endothelial function in hyperlipidemic children. Early detection and treatment of endothelial dysfunction in high-risk children may retard the progression of atherosclerosis.

Effect of docosahexaenoic acid on lipoprotein subclasses in hyperlipidemic children (the EARLY study).

To test the hypothesis that a dietary omega-3 fatty acid, docosahexaenoic acid, improves the lipoprotein subclass profile of children who have hyperlipidemia, we conducted a randomized, double-blind, placebo-controlled study. Children who had hyperlipidemia (n = 20) were stabilized on a low-fat diet for 6 weeks and then randomized to receive 1.2 g/day of docosahexaenoic acid for 6 weeks or placebo. Supplementation with docosahexaenoic acid significantly increased low-density lipoprotein subclass 1 and high-density lipoprotein subclass 2 (large and buoyant; less atherogenic particles) by 91% and 14%, respectively, compared with the placebo phase. Low-density lipoprotein subclass 3 (small and dense; more atherogenic particles) decreased by 48%.

Effects of docosahexaenoic acid on vascular pathology and reactivity in hypertension.

Previous studies have shown that docosahexaenoic acid (DHA) has an antihypertensive effect in spontaneously hypertensive rats (SHR). To investigate possible mechanisms for this effect, vascular pathology and reactivity were determined in SHR treated with dietary DHA. SHR (7 weeks) were fed a purified diet with either a combination of corn/soybean oils or a DHA-enriched oil for 6 weeks. Histological evaluation of heart tissue, aorta, coronary, and renal arteries was performed. Vascular responses were determined in isolated aortic rings. Contractile responses to agonists, including norepinephrine (10(-9) to 10(-4) M), potassium chloride (5-55 mM), and angiotensin II (5 x 10(-7) M) were assessed. Vasorelaxant responses to acetylcholine (10(-9) to 10 (-4) M), sodium nitroprusside (10(-9) to 10(-6) M), papaverine (10(-5) to 10(-4) M), and methoxyverapamil (D600, 1-100 microM) were determined. DHA-fed SHR had significantly reduced blood pressure (P < 0.001) and vascular wall thicknesses in the coronary, thoracic, and abdominal aorta compared with controls (P < 0.05) Contractile responses to agonists mediated by receptor stimulation and potassium depolarization were not altered in DHA-fed SHR. Endothelial-dependent relaxations to acetylcholine were not altered which suggests endothelial-derived nitric oxide production/release is not affected by dietary DHA. Other mechanisms of vascular relaxation, including intracellular cyclic nucleotides, cGMP, and cAMP were not altered by dietary DHA because aortic relaxant responses to sodium nitroprusside and papaverine were similar in control and DHA-fed SHR. No significant differences were seen in relaxant responses to the calcium channel blocker, D600, or contractile responses to norepinephrine in the absence of extracellular calcium. These results suggest that dietary DHA does not affect mechanisms related to extracellular calcium channels or intracellular calcium mobilization. Moreover, the contractile and vasorelaxant responses are not differentially altered with dietary DHA in this in vivo SHR model. The findings demonstrate that dietary DHA reduces systolic blood pressure and vascular wall thickness in SHR. This may contribute to decrease arterial stiffness and pulse pressure, in addition to the antihypertensive properties of DHA. The antihypertensive properties of DHA are not related to alterations in vascular responses.

Enteral nutritional intake in adult korean intensive care patients.

BACKGROUND: Nutritional support is important for maximizing clinical outcomes in critically ill patients, but enteral nutritional intake is often inadequate. OBJECTIVE: To assess the nutritional intake of energy and protein during the first 4 days after initiation of enteral feeding and to examine the relationship between intake and interruptions of enteral feeding in Korean patients in intensive care. METHODS: A cohort of 34 critically ill adults who had a primary medical diagnosis and received bolus enteral feeding were studied prospectively. Energy and protein requirements were determined by using the Harris-Benedict equation and the American Dietetic Association equation. Energy and protein intake prescribed and received and the reasons for and lengths of feeding interruptions were recorded for 4 consecutive days immediately after enteral feeding began. RESULTS: Although the differences between requirements and intakes of energy and protein decreased significantly, patients did not receive required energy and protein intake during the 4 days of the study. Energy intake prescribed was consistently less than required on each of the 4 days. Enteral nutrition was withheld for a mean of 6 hours per patient for the 4 days. Prolonged feeding interruptions due to gastrointestinal intolerance (r= -0.874; P < .001) and procedures (r= -0.839; P = .005) were negatively associated with the percentage of prescribed energy received. CONCLUSIONS: Enteral nutritional intake was insufficient in bolus-fed Korean intensive care patients because of prolonged feeding interruptions and underprescription of enteral nutrition. Feeding interruptions due to gastrointestinal intolerance and procedures were the main contributors to inadequate energy intake.

Why patients in critical care do not receive adequate enteral nutrition? A review of the literature.

Enteral nutrition is frequently used to provide nutrients for critically ill patients. However, only about half of critically ill enterally fed patients receive their energy requirements. Underfeeding is associated with detrimental clinical outcomes including infection, pressure ulcers, impaired wound healing, prolonged hospital stays, and increased morbidity and mortality. This literature review was conducted to identify major barriers to adequate enteral nutrition intake in critically ill adults and to identify gaps in the research literature. Studies (n = 30) reviewed addressed adult patients in critical care, published since 1999, and written in English. Findings showed that factors that explain inadequate enteral nutritional intake include delayed initiation of enteral nutrition and slow advancement of infusion rate, underprescription, incomplete delivery of prescribed nutrition, and frequent interruption of enteral nutrition. Frequent interruption was caused by diagnostic tests, surgical procedures, gastrointestinal intolerance, feeding tube problems, and routine nursing procedures. There are no standardized protocols that address these barriers to receiving adequate enteral intake. Such protocols must be developed, implemented, and tested to address undernutrition and mitigate the negative consequences of inadequate enteral intake.

Lipoprotein-associated phospholipase A(2): a promising vascular-specific marker for screening cardiovascular risk?

Atherosclerosis is an inflammatory disease that can be assessed by circulating biomarkers. Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an enzyme produced in atherosclerotic plaque and is bound to low density lipoprotein and high-density lipoprotein cholesterol. It has a role in the pathogenesis of atherosclerosis by promoting vascular inflammation. It is emerging as a vascular-specific marker and predictor of risk for cardiovascular disease (CVD) events. Increasing evidence from many prospective epidemiologic studies have shown that elevated levels of Lp-PLA(2) are associated with future CVD events. Measurement of Lp-PLA(2) in individuals may provide clinically relevant information about their future risk of CVD events. Pharmacologic therapies and/or risk factor modification could be initiated after identification of individuals at risk for CVD. This review provides an overview of the pathophysiology, epidemiologic evidence, and clinical utility of Lp-PLA(2).

Omega-3 fatty acids: role in cardiovascular health and disease.

Dietary omega-3 polyunsaturated fatty acids, eicosapentaenoic and docosahexaenoic acids, play an important role in cardiovascular health and disease. Clinical trials provide substantial evidence to support current dietary recommendations for omega-3 fatty acids in cardiovascular disease management. The cardioprotective benefits of omega-3 fatty acids may be attributed to multiple physiological effects on lipids, blood pressure, vascular function, cardiac rhythms, platelet function, and inflammatory responses. The metabolism of omega-3 fatty acids, physiological effects, and clinical considerations with current dietary recommendations and sources of omega-3 fatty acids are presented.

Induction of renal cytochrome P450 arachidonic acid epoxygenase activity by dietary gamma-linolenic acid.

Dietary gamma-linolenic acid (GLA), a omega-6 polyunsaturated fatty acid found in borage oil (BOR), lowers systolic blood pressure in spontaneously hypertensive rats (SHRs). GLA is converted into arachidonic acid (AA) by elongation and desaturation steps. Epoxyeicosatrienoic acids (EETs) and 20-hydroxyeicosatetraenoic acid (20-HETE) are cytochrome P450 (P450)-derived AA eicosanoids with important roles in regulating blood pressure. This study tested the hypothesis that the blood pressure-lowering effect of a GLA-enriched diet involves alteration of P450-catalyzed AA metabolism. Microsomes and RNA were isolated from the renal cortex of male SHRs fed a basal fat-free diet for 5 weeks to which 11% by weight of sesame oil (SES) or BOR was added. There was a 2.6- to 3.5-fold increase in P450 epoxygenase activity in renal microsomes isolated from the BOR-fed SHRs compared with the SES-fed rats. Epoxygenase activity accounted for 58% of the total AA metabolism in the BOR-treated kidney microsomes compared with 33% in the SES-treated rats. More importantly, renal 14,15- and 8,9-EET levels increased 1.6- to 2.5-fold after dietary BOR treatment. The increase in EET formation is consistent with increases in CYP2C23, CYP2C11, and CYP2J protein levels. There were no differences in the level of renal P450 epoxygenase mRNA between the SES- and BOR-treated rats. Enhanced synthesis of the vasodilatory EETs and decreased formation of the vasoconstrictive 20-HETE suggests that changes in P450-mediated AA metabolism may contribute, at least in part, to the blood pressure-lowering effect of a BOR-enriched diet.

Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adults.

BACKGROUND: Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids. OBJECTIVE: To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects. DESIGN: The study was a randomized, double-blind, placebo-controlled design conducted over a 2 week period in 21 healthy adult subjects. Subjects were randomly assigned to daily intake of high-flavonoid (213 mg procyanidins, 46 mg epicatechin) or low-flavonoid dark chocolate bars (46 g, 1.6 oz). RESULTS: High-flavonoid chocolate consumption improved endothelium-dependent flow-mediated dilation (FMD) of the brachial artery (mean change = 1.3 +/- 0.7%) as compared to low-flavonoid chocolate consumption (mean change = -0.96 +/- 0.5%) (p = 0.024). No significant differences were noted in the resistance to LDL oxidation, total antioxidant capacity, 8-isoprostanes, blood pressure, lipid parameters, body weight or body mass index (BMI) between the two groups. Plasma epicatechin concentrations were markedly increased at 2 weeks in the high-flavonoid group (204.4 +/- 18.5 nmol/L, p < or = 0.001) but not in the low-flavonoid group (17.5 +/- 9 nmol/L, p = 0.99). CONCLUSION: Flavonoid-rich dark chocolate improves endothelial function and is associated with an increase in plasma epicatechin concentrations in healthy adults. No changes in oxidative stress measures, lipid profiles, blood pressure, body weight or BMI were seen.