Increased Plasma Antioxidant Capacity Research Articles

Protective effect of a hydromethanolic extract from Fraxinus excelsior L. bark against a rat model of aluminum chloride-induced Alzheimer's disease: Relevance to its anti-inflammatory and antioxidant effects

Ethnopharmacological relevanceFraxinus excelsior L. (FE), commonly known as the ash, belongs to the Oleaceae family and has shown several pharmacological and biological properties, such as antioxidant, immunomodulatory, neuroprotective, and anti-inflammatory effects. It has also attracted the most attention toward neuroinflammation. Moreover, FE bark and leaves have been used to treat neurological disorders, aging, neuropathic pain, urinary complaints, and articular pain in traditional and ethnomedicine. Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder resulting from the involvement of amyloid-beta, metal-induced oxidative stress, and neuroinflammation. Aim of the studyThe objective of the current study was to assess the neuroprotective effects of hydromethanolic extract from FE bark in an AlCl3-induced rat model of AD. Materials and methodsThe maceration process was utilized to prepare the hydromethanolic extract of FE bark, and characterized by LC-MS/MS. To assess the anti-AD effects of the FE extract, rats were categorized into five different groups, AlCl3; normal control; FE-treated groups at 50, 100, and 200 mg/kg. Passive avoidance learning test, Y-maze, open field, and elevated plus maze behavioral tests were evaluated on days 7 and 14 to analyze the cognitive impairments. Zymography analysis, biochemical tests, and histopathological changes were also followed in different groups. ResultsLC-MS/MS analysis indicated the presence of coumarins, including isofraxidin7-O-diglucoside in the methanolic extract of FE as a new isofraxidin derivative in this genus. FE significantly improved memory and cognitive function, maintained weight, prevented neuronal damages, and preserved the hippocampus's histological features, as demonstrated by behavioral tests and histopathological analysis. FE increased anti-inflammatory MMP-2 activity, whereas it decreased that of inflammatory MMP-9. Moreover, FE increased plasma antioxidant capacity by enhancing CAT and GSH while decreasing nitrite levels in the serum of treated groups. In comparison between the treated groups, the rats that received high doses of the FE extract (200 mg/kg) showed the highest therapeutic effect. ConclusionFE rich in coumarins could be an effective anti-AD adjunct agent, passing through antioxidant and anti-inflammatory pathways. These results encourage further studies for the development of this extract as a promising agent in preventing, managing, or treating AD and related diseases.

Effects of Supplementation of Murici (Byrsonima crassifolia) and Taperebá (Spondias mombin) Pulp Extracts on Food Intake, Body Parameters, and Oxidative Stress Markers in Healthy Rats.

This study evaluates the effects of supplementation of murici (Byrsonima crassifolia) and taperebá (Spondias mombin) pulp extracts on dietary intake, body composition, biochemical parameters, and markers of oxidative stress. Two experiments were conducted with a total of 80 healthy male Wistar rats and a 30-day supplementation. In the first experiment, animals were divided into control (C) group, murici group 50 mg/(kg⸱day) (50Mu), murici group 100 mg/(kg⸱day) (100Mu), and murici group 200 mg/(kg⸱day) (200Mu). In the second experiment, animals were divided into C group, taperebá group 50 mg/(kg⸱day) (50Tap), taperebá group 100 mg/(kg⸱day) (100Tap), and taperebá group 200 mg/(kg⸱day) (200Tap). Results showed lower feed intake in 50Mu, 100Mu, and 100Tap groups (13%, 12%, and 10%, respectively, P < .05) and lower body fat in 200Mu, 100Tap, and 200Tap groups (16.0%, 29.1%, and 27.1%, respectively, P < .05). Only the 100Tap group showed reduced adipose tissue content (30.4%; P < .05). Increased plasma antioxidant capacity was observed at all doses for both fruits. Taperebá supplementation reduced ferrous oxidation-xylenol orange levels (50Tap: 8.4%, 100Tap: 16.1%, 200Tap: 24.3%; P < .05) and increased thiol levels (50Tap: 39%, 100Tap: 31%; P < .05). Serum thiobarbituric acid reactive substances levels were reduced in all groups receiving taperebá (50Tap: 77.7%, 100Tap: 73.1%, 200Tap: 73.8%; P < .05) and murici (50Mu: 44.5%, 100Mu: 34%, 200Mu: 43%; P < .05). Therefore, it is suggested that the inclusion of these fruits in the diet can contribute to health maintenance and disease prevention, through their effects on controlling food intake, improving body composition, and in combating oxidative stress.

Preeclampsia Affects Lipid Metabolism and HDL Function in Mothers and Their Offspring.

Preeclampsia (PE) is linked to an overall increased cardiovascular risk for both the mother and child. Functional impairment of high-density lipoproteins (HDL) may contribute to the excess cardiovascular risk associated with PE. In this study, we investigated the effects of PE on maternal and neonatal lipid metabolism, and the parameters of HDL composition and function. The study cohort included 32 normotensive pregnant women, 18 women diagnosed with early-onset PE, and 14 women with late-onset PE. In mothers, early- and late-onset PE was associated with atherogenic dyslipidemia, characterized by high plasma triglycerides and low HDL-cholesterol levels. We observed a shift from large HDL to smaller HDL subclasses in early-onset PE, which was associated with an increased plasma antioxidant capacity in mothers. PE was further associated with markedly increased levels of HDL-associated apolipoprotein (apo) C-II in mothers, and linked to the triglyceride content of HDL. In neonates of early-onset PE, total cholesterol levels were increased, whereas HDL cholesterol efflux capacity was markedly reduced in neonates from late-onset PE. In conclusion, early- and late-onset PE profoundly affect maternal lipid metabolism, potentially contributing to disease manifestation and increased cardiovascular risk later in life. PE is also associated with changes in neonatal HDL composition and function, demonstrating that complications of pregnancy affect neonatal lipoprotein metabolism.

In This Issue

HomeCirculation ResearchVol. 129, No. 5In This Issue Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIn This Issue Ruth Williams Ruth WilliamsRuth Williams Search for more papers by this author Originally published19 Aug 2021https://doi.org/10.1161/RES.0000000000000499Circulation Research. 2021;129:511is related toElectronic and Tobacco Cigarettes Alter Polyunsaturated Fatty Acids and Oxidative Biomarkersis related toGlucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal DialysisSilencing Myeloid Netrin-1 Induces Inflammation Resolution and Plaque RegressionElectronic and Tobacco Cigarettes Alter Polyunsaturated Fatty Acids and Oxidative Biomarkers (p 514)Gupta et al measure oxidized lipid biomarkers to assess health risks of electronic cigarettes.E-cigarettes have surged in popularity in the last decade. While they are generally viewed as a safe alternative to smoking tobacco, studies suggest that E-cigarettes, like tobacco ones, cause oxidative stress, inflammation and endothelial dysfunction in users. Indeed, the aerosols produced during vaping contain comparable levels of reactive oxygen species (ROS) to those in tobacco smoke. Data on the extent to which E-cigarette ROS influence cardiovascular health is lacking, however. To address this, Gupta and colleagues recruited 32 chronic users of E-cigarettes, 29 chronic tobacco smokers, and 45 individuals that used neither, and measured their plasma levels of oxidative biomarkers. The team found similarities and differences between E-cigarette and tobacco users. Both, for example, had increased plasma antioxidant capacity and decreased levels of oxidized linoleic acid compared with the levels seen in non-users, while arachidonic acid levels were raised in tobacco smokers and reduced in the E-cigarette users. Overall, however, biomarker levels were deemed to be intermediate for E-cigarette users between non-users and tobacco users. The study suggests, therefore, that while E-cigarettes carry a lower health risk than tobacco ones, they are by no means safe.Download figureDownload PowerPointGlucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal Dialysis (p e102)Glucose degradation products damage blood vessels during dialysis, report Bartosova et al.Diabetes, high blood pressure and obesity are risk factors for both cardiovascular disease (CVD) and chronic kidney disease (CKD). Worse still, loss of kidney function and even dialysis itself are thought to exacerbate cardiovascular issues. In the case of dialysis, it’s thought that high levels of glucose degradation products (GDPs) in the dialysis fluids can promote the addition of sugar moieties to vascular proteins and lipids (glycation), causing vessel damage. To investigate this theory, Bartosova and colleagues studied vascular tissue from children with CKD receiving dialysis fluid with either high levels or low levels of GDPs, or that were not on dialysis at all. Proteome and transcriptome analyses of the vessel tissues revealed that, compared with patients on no or low-GDP fluids, patients receiving high-GDP fluids had higher levels of damaging glycation, increased transcription of genes involved in cell death, and decreased transcription of genes involved in cell survival and cytoskeleton organization. In line with these findings, vessels from high-GDP patients displayed considerable evidence of damage (apoptosis, cytoskeletal disintergration, thickened intimas). The results thus confirm GDPs can cause vasculopathy and suggest low-GDP fluids should be favored for dialysis.Download figureDownload PowerPointTargeting Netrin-1 in Established Atherosclerosis Promotes Inflammation Resolution and Plaque Regression (p 530)Blocking netrin-1 diminishes atherosclerotic plaques in mice, say Schlegel et al.While excess lipids in the blood spur the development of atherosclerosis, the disease quickly becomes one of chronic inflammation that encourages the persistence of the lipid-filled plaques in vessel walls. Indeed, sustained inflammation is thought to explain why lipid-lowering drugs often aren’t enough to combat the condition. Inflammation-suppressing drugs are also being investigated, but because these may cause susceptibility to infections, Schlegel and colleagues reasoned that promoting resolution of inflammation may be a preferable goal. To that end, the team tested blocking nectrin-1 in atherosclerosis-prone mice. Originally identified as a factor essential for nerve cells, Netrin-1 has also been found in macrophages where it promotes persistence and survival of the cells in atherosclerotic plaques. The team showed that in mice with advanced atherosclerosis, turning off netrin-1 in macrophages—via an inducible genetic switch—led to significant plaque regression. Not only did plaque macrophages exhibit reduced retention, proliferation and survival, those that remained were more likely to be pro-resolving. While susceptibility to infection was not investigated in this study, the results suggest in principle that netrin-1 blockade could be a strategy for atherosclerosis treatment.Download figureDownload PowerPoint Previous Back to top Next FiguresReferencesRelatedDetailsRelated articlesElectronic and Tobacco Cigarettes Alter Polyunsaturated Fatty Acids and Oxidative BiomarkersRajat Gupta, et al. Circulation Research. 2021;129:514-526Glucose Derivative Induced Vasculopathy in Children on Chronic Peritoneal DialysisMaria Bartosova, et al. Circulation Research. 2021;129:e102-e118Silencing Myeloid Netrin-1 Induces Inflammation Resolution and Plaque RegressionMartin Schlegel, et al. Circulation Research. 2021;129:530-546 August 20, 2021Vol 129, Issue 5 Advertisement Article InformationMetrics © 2021 American Heart Association, Inc.https://doi.org/10.1161/RES.0000000000000499 Originally publishedAugust 19, 2021 PDF download Advertisement

Dietary Inclusion of Black Soldier Fly (Hermetia Illucens) Larvae Meal and Paste Improved Gut Health but Had Minor Effects on Skin Mucus Proteome and Immune Response in Atlantic Salmon (Salmo Salar).

The present study investigated effects of dietary inclusion of black soldier fly larvae (BSFL) (Hermetia illucens) meal and paste on gut health, plasma biochemical parameters, immune response and skin mucus proteome in pre-smolt Atlantic salmon (Salmo salar). The seven-week experiment consisted of seven experimental diets: a control diet based on fishmeal and plant protein (Control-1); three BSFL meal diets, substituting 6.25% (6.25IM), 12.5% (12.5IM) and 25% (25IM) of protein; two BSFL paste diets, substituting 3.7% (3.7IP) and 6.7% (6.7IP) of protein and an extra control diet with 0.88% of formic acid (Control-2). The 6.25IM diet reduced enterocyte steatosis in pyloric caeca, improved distal intestine histology, and reduced IgM in distal intestine. The fish fed 12.5IM diet reduced enterocyte steatosis in pyloric caeca, improved distal intestine histology, had a higher plasma lysozyme content compared to 6.25IM, and tend to increase phagocytic activity in head-kidney macrophages-like cells. On the other hand, 25IM diet improved distal intestine histology, but showed mild-moderate enterocyte steatosis in pyloric caeca, increased IFNγ and reduced IgM in distal intestine. In the case of BSFL paste diets, 3.7IP diet caused mild inflammatory changes in distal intestine, although it reduced enterocyte steatosis in pyloric caeca. The 6.7IP diet reduced enterocyte steatosis in pyloric caeca and improved distal intestine histology. Increasing level of BSFL meal in the diet linearly decreased plasma C-reactive protein, whereas increasing level of BSFL paste linearly increased plasma antioxidant capacity. Dietary inclusion of BSFL meal and paste had minor effects on the expression profile of proteins in skin mucus and no effects on immune markers in splenocytes. BSFL meal showed no negative effect on liver and muscle health as indicated by plasma alanine aminotranseferase, asparate aminotransferase and creatine kinase. The present study showed that replacing conventional protein sources with low to moderate levels of BSFL meal (6.25% and 12.5%) or paste (3.7% and 6.7%) reduced enterocyte steatosis in pyloric caeca, while replacing up to 25% with BSFL meal or 6.7% with paste improved distal intestine histology. Further, dietary inclusion of BSFL meal and paste had minor effects on skin mucus proteome and immune response in Atlantic salmon.

The effect of diet on oxidative stress and metabolic diseases-Clinically controlled trials.

Oxidative stress is associated with several chronic diseases. It is acknowledged that molecules damaged by reactive oxygen species activate the inflammatory process and that this response increases the production of free radicals. Modifications in a diet can improve or decrease redox state markers. The aim of this revision was to provide an update of clinical controlled trials, to assess changes in diet and markers of oxidative stress in subjects with metabolic diseases. They were investigated randomized controlled intervention studies (RCTs) published in MEDLINE (U.S. National Library of Medicine, National Institutes of Health) that were conducted in subjects with obesity, hypertension, diabetes, or dyslipidemia; with dietary intervention; where markers of oxidative stress have been evaluated and published in the last 5years. Food antioxidants, hypocaloric diets with loss of adipose tissue, substitution of animal protein by vegetable, and changes in the microbiota improve antioxidant status in people with chronic disease. PRACTICAL APPLICATIONS: Hyperglycemia in diabetes mellitus and adipose tissue in obesity are known to trigger oxidative stress. Oxidative stress, in turn, decreases insulin sensitivity and favors an inflammatory state producing adhesion molecules. Oxidative stress and adhesion molecules, can increase blood pressure and oxidation of lipoproteins, that ultimately could lead to a cerebrovascular event. Consumption of high-antioxidant and polyphenol foods increases plasma antioxidant capacity and decreases oxidative stress markers in people with diabetes, obesity, hypertension, and hypertriglyceridemia. In addition, weight loss caused by caloric restriction with or without exercise increases the endogenous antioxidant capacity. Therefore, it is likely that the combination of a hypocaloric diet with a high content of antioxidants and polyphenols will have a greater effect. Other dietary changes with antioxidant effect, such as the substitution of animal for vegetable protein or the addition of fiber, might be mediated by changes in the microbiota. However, this aspect requires further study.

Polyphenols and IUGR Pregnancies: Effects of Maternal Hydroxytyrosol Supplementation on Placental Gene Expression and Fetal Antioxidant Status, DNA-Methylation and Phenotype.

The use of polyphenols is a promising strategy for preventing or alleviating intrauterine growth restriction (IUGR) because polyphenol supplementation increases plasma antioxidant capacity and improves oxidative stress at the feto-placental unit; which are recognized as main issues in IUGR. However, there is a scarcity of experimental data on both realistic benefits and potential hazards of polyphenol supplementation during gestation. Hence, we aimed to use a swine model of IUGR pregnancy to determine possible effects of maternal supplementation with polyphenols (hydroxytyrosol) on placental expression of genes involved in antioxidant homeostasis, vascularization and fetal growth and thus on antioxidant status, DNA-methylation and phenotypic traits (morphology and homeostasis) of the fetus. Hydroxytyrosol improves placental gene expression and fetal antioxidant status and glucose metabolism in a sex-dependent manner, in which males were favored in spite of developmental failures. Concomitantly, hydroxytyrosol prevented hypomethylation of DNA associated with oxidative stress. Finally, no major deleterious effects of hydroxytyrosol supplementation on constriction of the ductus arteriosus, a possible secondary effect of polyphenols during pregnancy, were found.

Urtica dioica L. leaf extract modulates blood pressure and oxidative stress in spontaneously hypertensive rats

BackgroundUrtica dioica L. (Stinging nettle) has been used for centuries for the treatment of numerous health issues. PurposeThis study investigates the antioxidant capacity and the most abundant phenolic compounds of Urtica dioica L. leaf extract (UE), and its antihypertensive and antioxidative effects in vivo. Study designSpontaneously hypertensive rats were supplemented with 10, 50, and 200 mg/kg/day of UE and 10 mg/kg/day of losartan during 4-week period. MethodsIn this study, HPLC analysis of UE was performed, as well as the determination of antioxidant capacity, superoxide radical scavenging activity, and metal chelating ability. Hemodynamic parameters were measured directly in anesthetized rats. Also, antioxidant enzyme activity and concentration in erythrocytes were determined, as well as systemic oxidative stress and plasma antioxidant status. ResultsUE showed higher ferric reducing antioxidant power and Trolox equivalent antioxidant capacity than BHT, but lower than vitamin C. Furthermore, UE showed good metal chelating ability, but weak superoxide radical scavenging activity. All three tested UE doses managed to reduce systolic and diastolic blood pressure, as well as cardiac index, and to improve the antioxidative defense by increasing the activity of superoxide dismutase and catalase, without changing the concentration of the enzymes. Moreover, UE supplementation increased plasma antioxidant capacity and reduced systemic oxidative stress. ConclusionChronic UE dietary supplementation had beneficial effects in the experimental model of essential hypertension.

Acute effect of Clitoria ternatea flower beverage on glycemic response and antioxidant capacity in healthy subjects: a randomized crossover trial

BackgroundClitoria ternatea L., a natural food-colorant containing anthocyanin, demonstrated antioxidant and antihyperglycemic activity. The aim of this study was to determine the effects of Clitoria ternatea flower extract (CTE) on postprandial plasma glycemia response and antioxidant status in healthy men.MethodsIn a randomized, crossover study, 15 healthy men (ages 22.53 ± 0.30 years; with body mass index of 21.57 ± 0.54 kg/m2) consumed five beverages: (1) 50 g sucrose in 400 mL water; (2) 1 g CTE in 400 mL of water; (3) 2 g CTE in 400 mL of water; (4) 50 g sucrose and 1 g CTE in 400 mL of water; and (5) 50 g sucrose and 2 g CTE in 400 mL of water. Incremental postprandial plasma glucose, insulin, uric acid, antioxidant capacities and lipid peroxidation were measured during 3 h of administration.ResultsAfter 30 min ingestion, the postprandial plasma glucose and insulin levels were suppressed when consuming sucrose plus 1 g and 2 g CTE. In addition, consumption of CTE alone did not alter plasma glucose and insulin concentration in the fasting state. The significant increase in plasma antioxidant capacity (ferric reducing ability of plasma (FRAP), oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), and protein thiol) and the decrease in malondialdehyde (MDA) level were observed in the subjects who received 1 g and 2 g CTE. Furthermore, consumption of CTE protected sucrose-induced reduction in ORAC and TEAC and increase in plasma MDA.ConclusionsThese findings suggest that an acute ingestion of CTE increases plasma antioxidant capacity without hypoglycemia in the fasting state. It also improves postprandial glucose, insulin and antioxidant status when consumed with sucrose.Trial registrationThai Clinical Trials Registry: TCTR20170609003. Registered 09 September 2017.‘retrospectively registered’.

Acute Consumption of Bordo Grape Juice and Wine Improves Serum Antioxidant Status in Healthy Individuals and Inhibits Reactive Oxygen Species Production in Human Neuron-Like Cells.

Few studies investigated the biological effects of American grape cultivars. We investigated the metabolic response after acute consumption of grape juice or wine from Bordo grapes (Vitis labrusca) in a placebo-controlled crossover study with fifteen healthy volunteers. Blood samples were collected 1 hour after the intake of 100 mL of water, juice, or wine to measure TBARS, ABTS, FRAP, glucose, and uric acid levels. To evaluate differences in cellular response, intracellular reactive species production (DCFH-DA) and metabolic mitochondrial viability (MTT) were assessed after exposure of human neuron-like cells (SH-SY5Y) to juice or wine. Glycemia was reduced after juice or wine consumption, whereas blood levels of uric acid were reduced after juice consumption but increased after wine consumption. Juice and wine consumption reduced plasma lipid peroxidation and increased plasma antioxidant capacity (ABTS and FRAP assays). Furthermore, juice inhibited H2O2-induced intracellular production of reactive species (RS) and increased the viability of SH-SY5Y cells. In contrast, wine (dealcoholized) exhibited a per se effect by inducing the production of RS and reducing cell viability. These results indicate a positive impact of acute consumption of Bordo juice and wine on human oxidative status, whereas only juice had protective effects against oxidative stress-induced cytotoxicity.

PP-30 Clinical utility and safety of ganoderma lucidum extract in acute lymphoblastic leukaemia as a adjuvant therapy: a case report

Introduction Acute Lymphoblastic Leukaemia (ALL) is the most common childhood malignancy. Optimal util-isation of chemotherapy in addition with supportive care achieves highest survival rates (about 85%) for children. The main problem is the drug toxicity (mostly myelosup-pression, mucositis, and nausea/vomiting) as well as re-current infections. Complementary and Alternative Medicines (CAM) are often used in Paediatric Oncology. The medicinal mush-room Ganoderma lucidum plays a pivotal role as im-mune-modulator. Medicinal mushrooms are boosters or restoring agents of the ability of the immune system to fight infections, cancer and other diseases. The main bio-active compounds in Ganoderma lucidum are polysac-charides, in the form of beta-d-glucans, and triterpenes, both with well-defined biological properties. Beta-d-glucans have demonstrated antitumor and im-mune-stimulating activities. They modulate both innate and adaptive immune responses and increase opsonic and non opsonic phagocitosis, enhancing antitumor cytotoxicity. They also induce natural killer (NK) cell cy-totoxicity against various cancer. Triterpenes are able to inhibit cancer cell growth and activity as we showed in previous experients using different cancer cell lines.This mushroom also increases plasma antioxidant capacity and enhances immune response in cancer Aim Chemotherapy is a cause for neutropenia, increas-ing therefore the susceptibility to infections. Ganoderma lucidum previously showed to increase lymphoprolifer-ative responses in immunocompromized children with cancers in a randomised, double-blind and placebo-con-trolled study. However, clinical evidence supporting the use of medicinal mushrooms in paediatric patients is still scarce. Therefore, we decided to investigate the role of this mushroom in improving the quality of life, prevent-ing recurrences and infections in patients affected by ALL. Prior to any use the product developed, based on Local strains from Ganoderma lucidum, showed no inter-ference with the hepatic cytochromes, as we showed in previous studies Case study A 4 year old boy with confirmed diagnose of ALL type B without leucocitosis finished his chemothera-py treatment 2 years after the initial diagnose date, with a complete remission. The patient followed the protocol 58 081 of the EORTC with good response. After getting the Informed Consent from their parents, and estimate the initial dose based on BW (mg/Kg), the child received an oral dose of 445 mg of Ganoderma lucidum powder (Bioganoderma ©) daily with excellent tolerance. Six months later, we decided to double the dose with ex-cellent clinical response as well as tolerability. Two years later, daily providing the same oral dose, the patient still was free from infection (the neutropenia was corrected), no recurrence of his malignancy) or side effects referred. Blood tests are absolutely normal, as well as the myelo-gram. In fact, currently he follows a complete normal life (school, outdoors activities). He does not have any neurological or hepatic con-sequences from this treatment. His parents referred an impressive improving in his performance status since the child has being taking this mushroom compound, Ganoderma lucidum. Conclusions We need novel therapeutic approaches for Paediatric Cancer in order to improve the quality of life, prevent consequences and recurrences. As for adults, Ganoderma lucidum is an excellent opportunity for pae-diatric patients due to its safety, tolerability and clinical response.

Moringa Oleifera leaf extract increases plasma antioxidant status associated with reduced plasma malondialdehyde concentration without hypoglycemia in fasting healthy volunteers.

To investigate the effect of Moringa Oleifera leaf extract (MOLE) on plasma glucose concentration and antioxidant status in healthy volunteers. A randomized crossover design was used in this study. Healthy volunteers were randomly assigned to receive either 200 mL of warm water (10 cases) or 200 mL of MOLE (500 mg dried extract, 10 cases). Blood samples were drawn at 0, 30, 60, 90, and 120 min for measuring fasting plasma glucose (FPG), ferric reducing ability of plasma (FRAP), Trolox equivalent antioxidant capacity (TEAC) and malondialdehyde (MDA). FPG concentration was not signifificantly different between warm water and MOLE. The consumption of MOLE acutely improved both FRAP and TEAC, with increases after 30 min of 30 μmol/L FeSO4 equivalents and 0.18 μmol/L Trolox equivalents, respectively. The change in MDA level from baseline was signifificantly lowered after the ingestion of MOLE at 30, 60, and 90 min. In addition, FRAP level was negatively correlated with plasma MDA level after an intake of MOLE. MOLE increased plasma antioxidant capacity without hypoglycemia in human. The consumption of MOLE may reduce the risk factors associated with chronic degenerative diseases.

The Healthy Effects of Strawberry Polyphenols: Which Strategy behind Antioxidant Capacity?

Current evidence indicates that the consumption of strawberries, a natural source of a wide range of nutritive and bioactive compounds, is associated with the prevention and improvement of chronic-degenerative diseases. Studies involving cells and animals provide evidence on the anti-inflammatory, anticarcinogenic and antiproliferative activity of the strawberry. Epidemiological and clinical studies demonstrate that its acute consumption increases plasma antioxidant capacity, improves circulating inflammatory markers and ameliorates postprandial glycemic response. At the same time, a protracted intake reduces chronic inflammation and improves plasma lipid profile, supporting cardiovascular health, especially in individuals with increased risk for metabolic syndrome. To explain these beneficial effects, much attention has been paid in the past to the antioxidant properties of strawberry polyphenols. However, recent research has shown that their biological and functional activities are related not only to the antioxidant capacity but also to the modulation of many cellular pathways involved in metabolism, survival, proliferation, and antioxidant defenses. The aim of this review is to update and discuss the molecular and cellular mechanisms proposed in recent studies to elucidate the healthy effects of strawberry polyphenols against the most common chronic diseases, such as cancer, cardiovascular diseases, metabolic syndrome, and inflammation.

The protective effect of the Mediterranean diet on endothelial resistance to GLP-1 in type 2 diabetes: a preliminary report.

BackgroundIn type 2 diabetes, acute hyperglycemia worsens endothelial function and inflammation,while resistance to GLP-1 action occurs. All these phenomena seem to be related to the generation of oxidative stress. A Mediterranean diet, supplemented with olive oil, increases plasma antioxidant capacity, suggesting that its implementation can have a favorable effect on the aforementioned phenomena. In the present study, we test the hypothesis that a Mediterranean diet using olive oil can counteract the effects of acute hyperglycemia and can improve the resistance of the endothelium to GLP-1 action.MethodsTwo groups of type 2 diabetic patients, each consisting of twelve subjects, participated in a randomized trial for three months, following a Mediterranean diet using olive oil or a control low-fat diet. Plasma antioxidant capacity, endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels were evaluated at baseline and at the end of the study. The effect of GLP-1 during a hyperglycemic clamp, was also studied at baseline and at the end of the study.ResultsCompared to the control diet, the Mediterranean diet increased plasma antioxidant capacity and improved basal endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels. The Mediterranean diet also reduced the negative effects of acute hyperglycemia, induced by a hyperglycemic clamp, on endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels. Furthermore, the Mediterranean diet improved the protective action of GLP-1 on endothelial function, nitrotyrosine, 8-iso-PGF2a, IL-6 and ICAM-1 levels, also increasing GLP-1-induced insulin secretion.ConclusionsThese data suggest that the Mediterranean diet, using olive oil, prevents the acute hyperglycemia effect on endothelial function, inflammation and oxidative stress, and improves the action of GLP-1, which may have a favorable effect on the management of type 2 diabetes, particularly for the prevention of cardiovascular disease.

Abstract 068: Ghrelin Restores Nitric Oxide Availability In The Forearm Microcirculation Of Essential Hypertensive Patients

Objective: Essential hypertensive patients (EH) are characterized by endothelial dysfunction caused by a reduced nitric oxide (NO) availability due to reactive oxygen species excess and low-grade inflammatory condition. Ghrelin is a recently identified growth hormone-releasing peptide, with recognized cardiovascular actions. Possible effects on endothelial dysfunction have been never investigated in EH. In this study we evaluated whether exogenous ghrelin can improve endothelial dysfunction in the forearm microcirculation of untreated mild-moderate EH. Methods: In 9 EH (51.8±8.1 yrs) and 9 normotensive subjects (NS, 50.5±3.5 yrs), we studied the forearm blood flow (FBF, strain-gauge plethysmography) response to intrabrachial acetylcholine (ACh, 0.15-15 mg/100 ml/min) with and without NO synthase blockade by L-NMMA (100 μg/100 ml/min), or the antioxidant vitamin (Vit) C (8 mg/100 ml/min). The protocol was repeated under exogenous ghrelin intra-arterial infusion (200 ng/min, 30’ pre-infusion). Results: In NS, maximal vasodilation (VD) to ACh (480±20%) was inhibited by L-NMMA (292±22, -39±7%; P&lt;0.001) and unchanged by Vit C (482±34%). Ghrelin failed to modify these vascular responses. In EH, VD to ACh was blunted vs NS (337±45%; P&lt;0.001) and resistant to L-NMMA (313±32, -7±3%). Vit C increased the response to ACh (509±57%; P&lt;0.01 vs ACh alone) and restored the inhibiting effect of L-NMMA (332±42, -34±8%; P&lt;0.001). Ghrelin, while not modifying the basal FBF, it increased (P&lt;0.001) the VD to ACh (448±55%) and restored the inhibitory effect of L-NMMA on ACh (355±43, -20±6%; P&lt;0.001). Vit C only slightly improved VD to ACh under ghrelin infusion (486±45%). In EH ghrelin significantly (P&lt;0.05) decreased plasma venous malodialdehyde (from 6.9±1.5 to 5.2±1.0 μmol/L), lipoperoxides (from 9.1±1.9 to 6.6±2.3 μmol/L) and IL-6 (from 11.1±0.6 to 9.3±1.0 pg/mL) and increased plasma antioxidant capacity (from 407±109 to 630±97 mmol/L). Response to sodium nitroprusside was similar between EH and NS and not affected by ghrelin. Conclusions: Exogenous ghrelin is able to ameliorate endothelial dysfunction by restoring NO availability in the forearm microcirculation of EH, an effect probably determined by antioxidant and/or anti-inflammatory activities.

Long-Term Effect of an Aqueous Fraxinus excelsior L. Seed Extract in Spontaneously Hypertensive Rats.

The effect of long-term intake of different doses (20, 40, and 60 mg/kg/day) of a Fraxinus excelsior L. seed extract (FESE) on spontaneously hypertensive rats (SHR) was evaluated. Water was used as control and captopril (50 mg/kg/day) was used as positive control. Systolic blood pressure, body weight, and food and liquid intake were registered weekly in SHR. The antioxidant and vascular relaxing properties of FESE were also studied in these animals. The development of hypertension was attenuated in the groups treated with captopril or FESE. The antihypertensive effect was more accentuated in the captopril group than in the FESE groups, and it was paradoxically more accentuated in the groups treated with 20 mg/kg/day or 40 mg/kg/day of FESE than in the group treated with the highest dose of this extract. Body weight gain and food intake increased in the FESE groups. After removing the corresponding antihypertensive treatment, the arterial blood pressure and the body weight of the FESE treated animals returned to control values. In addition, FESE increased plasma antioxidant capacity and decreased plasma and liver malondialdehyde levels. Moreover, acetylcholine relaxation improved in the aorta rings from the FESE treated rats.

Bioactivity and bioavailability of minerals in rats loaded with cholesterol and kiwi fruit

The aim of this study was to compare the content of polyphenols (TP), minerals, ascorbic acid (AA) and total antioxidant capacities (TAC) of conventional and organic kiwifruit ‘Hayward’ treated with ethylene after harvest and to determine their influence on plasma TAC, mineral content in the liver and bioavailability (RBV — relative bioavailability value) in rats fed diet containing cholesterol. Organic and conventionally grown kiwifruits ‘Hayward’ as supplementation to rat diet were investigated in vitro for their bioactive compounds (polyphenols, flavonoids, flavanols, tannins, dietary fiber, and ascorbic acid), minerals, trace elements and TAC. In the in vivo investigation, 36 male Wistar rats (111±5g) were randomly divided into six diet groups, each of 6 rats: control without cholesterol (C) and 5 groups with 1% cholesterol (ch). Four cholesterol groups were supplemented with 5% lyophilized kiwifruit: ethylene treated, organic (chOHE) or conventional (chCHE) and untreated, and organic (chOHC) or conventional (chCHC). During a period of 33days of ad libitum feeding feed intake, body weight and feed utilization ration (FER) were controlled. In the end of the experiment rats were anesthetized using Narcotan and sacrificed, and blood and liver were assessed. Testing of antioxidant activity in plasma, minerals and trace elements in the diet and in the liver was performed. Ethylene-treated organic kiwifruit (OHE) had the highest content of TP and TAC. Mg content was significantly higher and Mn was lower in organic kiwifruit ‘Hayward’. Inverse relationship in the case of Mn in conventional kiwifruit was found. Supplementation of kiwifruit in ch diet groups improved diet palatability, influenced the increase of feed intake and body gain and also improved FER (lower values). Significant increase of plasma TAC for DPPH (19%), FRAP (68%) and ABTS (62%) in rats fed diets with kiwifruits was obtained. Ethylene treated conventional and organic kiwifruit improved (vs ch group) the antioxidant status of the rat body. Bioavailability of Mn and Zn in rats, calculated on the basis of its content in the liver was significantly lower in chOHC in comparison with ch group. Supplementation of ch diet groups with kiwifruit significantly decreased Mg bioavailability. Ethylene treated kiwifruit had no effect on mineral bioavailability in rats. Organic kiwifruit ‘Hayward’ contains more bioactive compounds, and showed higher antioxidant capacity than the conventional. Ethylene treatment of kiwifruit after harvest increases its bioactivity. Growing conditions of kiwifruit affect their Mg and Mn contents. Supplementation of kiwifruit in atherogenic diet increased plasma antioxidant capacity in rats. Similar effect was estimated for organic and conventional fruits. The ethylene treated kiwifruit significantly decreased magnesium bioavailability determined on the basis of its concentration in the liver. Supplementation of Mg in hypercholesterolemia is an important factor.

Short-term effect of an aqueous Fraxinus excelsior L. seed extract in spontaneously hypertensive rats

We evaluate the short-term effect of a Fraxinus excelsior L. seed extract, named FraxiPure (FRP) on spontaneously hypertensive rats (SHR). Water, Captopril and different doses of FRP were orally administered. Blood pressure was recorded by the tail cuff method and plasma samples were collected to determine antioxidant capacity and malondialdehyde equivalents. In other trials, 18h fasted SHR were administered water, FRP, Furosemide, Torasemide, and Captopril. In these animals, urine was collected for 4h to obtain the urine volumetric excretion (UVE). Plasma samples of these animals were used to establish the fractional excretion (FE) of different ions (Na+, Cl−, K+, Ca2+ and PO43−) and metabolites (creatinine, urea and uric acid).FRP shows antihypertensive effect. The decrease in blood pressure caused by FRP was slightly lower than that of Captopril and more accentuated than that of Torasemide. FRP and Torasemide significantly increased UVE. Torasemide significantly increased FE(Na+) and FE(Cl−) and showed a clear uricosuric effect. FRP showed slight natriuretic effects and behaved as a potassium-sparing diuretic. FRP significantly increased plasma antioxidant capacity and decreased plasma malondialdehyde equivalents. The antihypertensive effect of FRP in SHR can therefore be related with its diuretic and antioxidant properties.

Green tea supplementation increases glutathione and plasma antioxidant capacity in adults with the metabolic syndrome

Green tea, a popular polyphenol-containing beverage, has been shown to alleviate clinical features of the metabolic syndrome. However, its effects in endogenous antioxidant biomarkers are not clearly understood. Thus, we tested the hypothesis that green tea supplementation will upregulate antioxidant parameters (enzymatic and nonenzymatic) in adults with the metabolic syndrome. Thirty-five obese participants with the metabolic syndrome were randomly assigned to receive one of the following for 8 weeks: green tea (4 cups per day), control (4 cups water per day), or green tea extract (2 capsules and 4 cups water per day). Blood samples and dietary information were collected at baseline (0 week) and 8 weeks of the study. Circulating carotenoids (α-carotene, β-carotene, lycopene) and tocopherols (α-tocopherol, γ-tocopherol) and trace elements were measured using high-performance liquid chromatography and inductively coupled plasma mass spectroscopy, respectively. Serum antioxidant enzymes (glutathione peroxidase, glutathione, catalase) and plasma antioxidant capacity were measured spectrophotometrically. Green tea beverage and green tea extract significantly increased plasma antioxidant capacity (1.5 to 2.3 μmol/L and 1.2 to 2.5 μmol/L, respectively; P < .05) and whole blood glutathione (1783 to 2395 μg/g hemoglobin and 1905 to 2751 μg/g hemoglobin, respectively; P < .05) vs controls at 8 weeks. No effects were noted in serum levels of carotenoids and tocopherols and glutathione peroxidase and catalase activities. Green tea extract significantly reduced plasma iron vs baseline (128 to 92μg/dL, P < .02), whereas copper, zinc, and selenium were not affected. These results support the hypothesis that green tea may provide antioxidant protection in the metabolic syndrome.

Nutritional Antioxidants and Their Applications in Cardiometabolic Diseases

There is an increasing global trend in cardiometabolic disorders being a leading cause of morbidity and mortality. Adverse dietary habits and sedentary lifestyles contribute to cardiovascular disease (CVD) and diabetes mellitus (DM). Dietary nutrients in nuts have attracted attention in recent literature due to their beneficial effects on CVD by attenuating lipid profiles, inflammation and oxidative stress. There is well-established evidence of the pharmacological properties of micronutrients that render them therapeutically effective in chronic inflammatory diseases. Although caution should be exercised in using antioxidant supplementation, antioxidant foods as dietary components play an important role in the management of cardiometabolic disorders. There is documented evidence of disease-modifying effects of nutritional compounds with anti-inflammatory and antioxidant effects. They have specific applications in ameliorating oxidative stress- induced inflammatory diseases such as DM and CVD. It is relevant that dietary components that influence risk of DM, have similar effects on inflammatory biomarkers of cardiovascular risk. Polyphenolic compounds such as flavonoids, isoflavones, phenolic acids and lignan contribute to increased plasma antioxidant capacity, decreased oxidative stress markers and reduced total and LDL cholesterol. They modulate genes associated with metabolism, stress defence, detoxification and transporter proteins. Their antioxidant and anti-inflammatory actions have specific applications for pathologies associated with chronic low-grade systemic inflammation that underpins progression of DM and CVD. Mechanisms involved depend on the structure of the compound, redox status of the inflammatory milieu and other interactions. Bioactive phytochemicals play an important therapeutic role in attenuating oxidative damage induced by metabolic syndrome associated with atherogenic dyslipidaemia and a pro-inflammatory, pro-thrombotic state, at a sub-cellular level. It would be critical to formulate optimal proportions and their combinations for therapeutic efficacy, based on synergistic interactions. Some of these mechanisms and potential actions are discussed.