Frozen fruit pulp of Euterpe oleraceae Mart. (Acai) prevents hydrogen peroxide-induced damage in the cerebral cortex, cerebellum, and hippocampus of rats

What We Know about Euterpe Genus and Neuroprotection: A Scoping Review

The Euterpe genus (mainly Euterpe oleracea Martius, Euterpe precatoria Martius, and Euterpe edulis Martius) has recently gained commercial and scientific notoriety due to the high nutritional value of its fruits, which are rich in polyphenols (phenolic acids and anthocyanins) and have potent antioxidant activity. These characteristics have contributed to the increased number of neuropharmacological evaluations of the three species over the last 10 years, especially açaí of the species Euterpe oleracea Martius. The fruits of the three species exert neuroprotective effects through the modulation of inflammatory and oxidative pathways and other mechanisms, including the inhibition of the mTOR pathway and protection of the blood-brain barrier, all of them intimately involved in several neuropathologies. Thus, a better understanding of the neuropharmacological properties of these three species may open new paths for the development of therapeutic tools aimed at preventing and treating a variety of neurological conditions.

Association between HSPA8 Gene Variants and Ischemic Stroke: A Pilot Study Providing Additional Evidence for the Role of Heat Shock Proteins in Disease Pathogenesis

HSPA8 is involved in many stroke-associated cellular processes, playing a pivotal role in the protein quality control system. Here we report the results of the pilot study aimed at determining whether HSPA8 SNPs are linked to the risk of ischemic stroke (IS). DNA samples from 2139 Russians (888 IS patients and 1251 healthy controls) were genotyped for tagSNPs (rs1461496, rs10892958, and rs1136141) in the HSPA8 gene using probe-based PCR. SNP rs10892958 of HSPA8 was associated with an increased risk (risk allele G) of IS in smokers (OR = 1.37; 95% CI = 1.07-1.77; p = 0.01) and patients with low fruit and vegetable consumption (OR = 1.36; 95% CI = 1.14-1.63; p = 0.002). SNP rs1136141 of HSPA8 was also associated with an increased risk of IS (risk allele A) exclusively in smokers (OR = 1.68; 95% CI = 1.23-2.28; p = 0.0007) and in patients with a low fruit and vegetable intake (OR = 1.29; 95% CI = 1.05-1.60; p = 0.04). Sex-stratified analysis revealed an association of rs10892958 HSPA8 with an increased risk of IS in males (risk allele G; OR = 1.30; 95% CI = 1.05-1.61; p = 0.01). Thus, SNPs rs10892958 and rs1136141 in the HSPA8 gene represent novel genetic markers of IS.

Acai Berry (Euterpe sp.) Extracts Are Neuroprotective against L-Glutamate-Induced Toxicity by Limiting Mitochondrial Dysfunction and Cellular Redox Stress

Aberrant accumulation of the neurotransmitter L-glutamate (L-Glu) has been implicated as a mechanism of neurodegeneration, and the release of L-Glu after stroke onset leads to a toxicity cascade that results in neuronal death. The acai berry (Euterpe oleracea) is a potential dietary nutraceutical. The aim of this research was to investigate the neuroprotective effects of acai berry aqueous and ethanolic extracts to reduce the neurotoxicity to neuronal cells triggered by L-Glu application. L-Glu and acai berry effects on cell viability were quantified using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays, and effects on cellular bioenergetics were assessed via quantitation of the levels of cellular ATP, mitochondrial membrane potential (MMP), and production of reactive oxygen species (ROS) in neuroblastoma cells. Cell viability was also evaluated in human cortical neuronal progenitor cell culture after L-Glu or/and acai berry application. In isolated cells, activated currents using patch-clamping were employed to determine whether L-Glu neurotoxicity was mediated by ionotropic L-Glu-receptors (iGluRs). L-Glu caused a significant reduction in cell viability, ATP, and MMP levels and increased ROS production. The co-application of both acai berry extracts with L-Glu provided neuroprotection against L-Glu with sustained cell viability, decreased LDH production, restored ATP and MMP levels, and reduced ROS levels. Whole-cell patch-clamp recordings showed that L-Glu toxicity is not mediated by the activation of iGluRs in neuroblastoma cells. Fractionation and analysis of acai berry extracts with liquid chromatography-mass spectrometry identified several phytochemical antioxidants that may have provided neuroprotective effects. In summary, the acai berry contains nutraceuticals with antioxidant activity that may be a beneficial dietary component to limit pathological deficits triggered by excessive L-Glu accumulations.

Açaí (Euterpe oleracea Mart.) in Health and Disease: A Critical Review

The açaí palm (Euterpe oleracea Mart.), a species belonging to the Arecaceae family, has been cultivated for thousands of years in tropical Central and South America as a multipurpose dietary plant. The recent introduction of açaí fruit and its nutritional and healing qualities to regions outside its origin has rapidly expanded global demand for açaí berry. The health-promoting and disease-preventing properties of this plant are attributed to numerous bioactive phenolic compounds present in the leaf, pulp, fruit, skin, and seeds. The purpose of this review is to present an up-to-date, comprehensive, and critical evaluation of the health benefits of açaí and its phytochemicals with a special focus on cellular and molecular mechanisms of action. In vitro and in vivo studies showed that açaí possesses antioxidant and anti-inflammatory properties and exerts cardioprotective, gastroprotective, hepatoprotective, neuroprotective, renoprotective, antilipidemic, antidiabetic, and antineoplastic activities. Moreover, clinical trials have suggested that açaí can protect against metabolic stress induced by oxidation, inflammation, vascular abnormalities, and physical exertion. Due to its medicinal properties and the absence of undesirable effects, açaí shows a promising future in health promotion and disease prevention, in addition to a vast economic potential in the food and cosmetic industries.

A Preliminary Assessment of the Nutraceutical Potential of Acai Berry (Euterpe sp.) as a Potential Natural Treatment for Alzheimer's Disease

Alzheimer's disease (AD) is characterised by progressive neuronal atrophy and the loss of neuronal function as a consequence of multiple pathomechanisms. Current AD treatments primarily operate at a symptomatic level to treat a cholinergic deficiency and can cause side effects. Hence, there is an unmet need for healthier lifestyles to reduce the likelihood of AD as well as improved treatments with fewer adverse reactions. Diets rich in phytochemicals may reduce neurodegenerative risk and limit disease progression. The native South American palm acai berry (Euterpe oleraceae) is a potential source of dietary phytochemicals beneficial to health. This study aimed to screen the nutraceutical potential of the acai berry, in the form of aqueous and ethanolic extracts, for the ability to inhibit acetyl- and butyryl-cholinesterase (ChE) enzymes and scavenge free radicals via 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) or 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays. In addition, this study aimed to quantify the acai berry's antioxidant potential via hydrogen peroxide or hydroxyl scavenging, nitric oxide scavenging, lipid peroxidation inhibition, and the ability to reduce ferric ions. Total polyphenol and flavonoid contents were also determined. Acai aqueous extract displayed a concentration-dependent inhibition of acetyl- and butyryl-cholinesterase enzymes. Both acai extracts displayed useful concentration-dependent free radical scavenging and antioxidant abilities, with the acai ethanolic extract being the most potent antioxidant and displaying the highest phenolic and flavonoid contents. In summary, extracts of the acai berry contain nutraceutical components with anti-cholinesterase and antioxidant capabilities and may therefore provide a beneficial dietary component that limits the pathological deficits evidenced in AD.

Neuroprotective activities of acai berries (Euterpe sp.): A review

Dietary interventions rich in fruits and vegetables in aging people can reverse or mitigate age-related cognitive declines, delay the onset of neurodegenerative diseases (NDDs), and provide long-term health dividends. The novel food, popularly known as "Acai", is a berry belonging to the Euterpe genus of tropical palms trees and natively found in South America. Euterpe oleracea has been given much attention among scientists due to its high antioxidant capacity compared to other fruits and berries. Additionally, acai pulp composition analysis found that it contains various biologically active phytochemicals. In this review, we focused on current evidence relating to acai berry neuroprotection mechanisms and its efficacy in preventing or reversing neurodegeneration and age-related cognitive decline. A number of studies have illustrated the potential neuroprotective properties of acai berries. They have shown that their chemical extracts have antioxidant and anti-inflammatory properties and maintain proteins, calcium homeostasis, and mitochondrial function. Moreover, acai berry extract offers other neuromodulatory mechanisms, including anticonvulsant, antidepressant, and anti-aging properties. This neuromodulation gives valuable insights into the acai pulp and its considerable pharmacological potential on critical brain areas involved in memory and cognition. The isolated chemical matrix of acai berries could be a new substitute in research for NDD medicine development. However, due to the limited number of investigations, there is a need for further efforts to establish studies that enable progressing to clinical trials to consequently prove and ratify the therapeutic potential of this berry for several incurable NDDs.

Hemp Seeds, Flaxseed, and Açaí Berries: Health Benefits and Nutritional Importance with Emphasis on the Lipid Content

Abstract:

Some plant seeds and berries have gained increased recognition due to their wide variety of bioactive compounds. Many of these foods are rich in lipids with high nutritional value, of which n-3 and n-6 essential fatty acids stand out. However, knowledge of the chemical composition and biological activity of these compounds and their value as a source of healthy lipids is far from being fully explored. The benefits of the intake of hemp seeds, flaxseed, and açaí berries, considered functional foods, have been compiled in this review. Likewise, their general chemical composition will be described to evaluate their relevance in a healthy diet, highlighting their lipid components and health lipid indices. The fibres and essential fatty acids of hemp seeds and flaxseed and the antioxidant properties of açaí berries provide them protective roles against several chronic non-communicable diseases and represent significant beneficial effects that add value to these healthy natural products. More research is needed to deepen the knowledge on their lipids’ molecular composition and bioactivity.

Dietary Euterpe oleracea Mart. attenuates seizures and damage to lipids in the brain of Colossoma macropomum

The Amazonian açai fruit (Euterpe oleracea) has shown promising anticonvulsant properties, comparable to those of diazepam (BDZ) in in vivo models submitted to pentylenetetrazole (PTZ). PTZ is a classic convulsant agent used in studies for the purpose of screening anticonvulsants and investigating the mechanisms of epilepsy. Herein, we aimed to determine, for the first time, the effect of dietary administration of lyophilized E. oleracea (LEO) on PTZ-induced seizures, using juvenile Colossoma macropomum fish (9.1 ± 1.5 g) as a model. A control diet (0.00% LEO) and two levels of LEO inclusion were established: 5.00% and 10.0% LEO (w/w). Fish were divided into five groups (n = 5): control (0.9% physiological solution; i.p.), PTZ (PTZ 150 mg kg^-1; i.p.), PTZ LEO 5.00%, PTZ LEO 10.0%, and BDZ-PTZ (BDZ: diazepam 10 mg kg^-1; i.p.). In addition to the electroencephalography (EEG), the lipid peroxidation (TBARS) was quantified in the brain, along with the characterization of behavioral responses. Fish receiving PTZ showed intense action potential bursts (APB), which overlapped with a hyperactive behavior. In PTZ LEO 5.00% and 10.0% groups, convulsive behavior was significantly reduced compared to the PTZ group. Fish fed 5.00% or 10.0% LEO and exposed to PTZ showed less excitability and lower mean amplitude in tracings. The inclusion of 10.0% LEO in the diet prevented the increase in mean amplitude of the EEG waves by 80%, without significant differences to the quantified mean amplitude of the BDZ-PTZ group. TBARS concentration was reduced by 60% in the brain of fish fed 10.0% LEO-enriched diets relative to the PTZ-administered group. The results of this study demonstrated the anticonvulsant and protective roles of LEO to the brain, and the dietary inclusion of LEO seems to be promising for the formulation of functional diets. Results of this study may boost the interest on the anti-seizurogenic properties of Euterpe oleracea, including the development of new approaches for the prevention of seizures in humans and animals with low epileptic threshold.

Optimization of Microwave and Ultrasound Extraction Methods of Açai Berries in Terms of Highest Content of Phenolic Compounds and Antioxidant Activity

Rapid technological progress focuses on lowering costs, labor and time. Thus, in order to minimize the expenses of bioactive compound production, great effort is undertaken to optimize the extraction of these compounds. Green extraction is popular and relatively inexpensive. However, the same extraction method does not always work for all types of matrixes due to the biological diversity of the tissue. Therefore, the purpose of this study was to identify the optimal green extraction method of açai berries (ultrasound or microwaves) able to isolate extracts containing the highest possible number of phenolic compounds with the highest antioxidant activity. The results show that the highest content of total phenolic compounds in the extracts was obtained after the application of a temperature of 45 °C, using ultrasound for 25 min and 45 min, microwaves for 3.16 min and a water bath for 25 min. Ultrasound turned out to be the most effective method of flavonoid extraction. In turn, the highest anthocyanin content was obtained for microwave extraction. Additionally, the application of microwaves for 4.33 min (45 °C) guaranteed the highest ferric-reducing antioxidant activity (FRAP) among the extracts. The results show that the use of microwaves shortens the açai extraction time and ensures both a high content of total phenolic compounds and strong antioxidant activity in the extract.

Euterpe Oleracea Mart. (Açaí) Reduces Oxidative Stress and Improves Energetic Metabolism in Myocardial Ischemia-Reperfusion Injury in Rats

Background

Euterpe oleracea Mart. (açaí) is a fruit with high antioxidant capacity and could be an adjuvant strategy to attenuate ischemia-reperfusion injury.

Objective

To evaluate the influence of açaí in global ischemia-reperfusion model in rats.

Methods

Wistar rats were assigned to 2 groups: Control (C: receiving standard chow; n = 9) and Açaí (A: receiving standard chow supplemented with 5% açaí; n = 10). After six weeks, the animals were subjected to the global ischemia-reperfusion protocol and an isolated heart study to evaluate left ventricular function. Level of significance adopted: 5%.

Results

There was no difference between the groups in initial body weight, final body weight and daily feed intake. Group A presented lower lipid hydroperoxide myocardial concentration and higher catalase activity, superoxide dismutase and glutathione peroxidase than group C. We also observed increased myocardial activity of b-hydroxyacyl coenzyme-A dehydrogenase, pyruvate dehydrogenase, citrate synthase, complex I, complex II and ATP synthase in the A group as well as lower activity of the lactate dehydrogenase and phosphofructokinase enzymes. The systolic function was similar between the groups, and the A group presented poorer diastolic function than the C group. We did not observe any difference between the groups in relation to myocardial infarction area, total and phosphorylated NF-kB, total and acetylated FOXO1, SIRT1 and Nrf-2 protein expression.

Conclusion

despite improving energy metabolism and attenuating oxidative stress, açai supplementation did not decrease the infarcted area or improve left ventricular function in the global ischemia-reperfusion model.

Impacts of the supplementation of açai lump flour in the diet of laying hens on productive performance, and fatty acid profiles and antioxidant capacity in the fresh and stocked eggs

The aim of this study was to evaluate whether the supplementation with açaí flour in the feed of laying hens at the end of the production cycle has beneficial effects on the health and performance of the birds and on the quality of the eggs. Groups received basal diets supplemented with 0%, 0.25%, 0.5%, 1.0%, and 2.0% açaí lump flour. We observed better productivity linked to oviposition and egg mass in a dose-dependent manner. We also observed higher shell resistance in stored eggs and higher % albumen and peel in fresh eggs. Lower levels of lipoperoxidation were observed in fresh eggs (2.0%). In stored eggs, lipoperoxidation levels were lower in all supplemented groups. The antioxidant capacity levels in fresh or stored eggs was higher (2.0%). We also observed a higher content of monounsaturated fatty acids in the supplemented groups, whereas saturated fatty acids were lower in the egg yolks. PRACTICAL APPLICATIONS: Based on a regression analysis, we verified that 1.47% of açaí flour is ideal in terms of productive efficiency. Dietary supplementation with açaí flour improved performance, egg quality, and had positive effects on the health of hens. Supplementation with açaí flour increased egg shelf life, reducing lipid peroxidation, biochemical reaction responsible for egg putrefaction.

Anthocyanins and Their Metabolites as Therapeutic Agents for Neurodegenerative Disease

Neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS), are characterized by the death of neurons within specific regions of the brain or spinal cord. While the etiology of many neurodegenerative diseases remains elusive, several factors are thought to contribute to the neurodegenerative process, such as oxidative and nitrosative stress, excitotoxicity, endoplasmic reticulum stress, protein aggregation, and neuroinflammation. These processes culminate in the death of vulnerable neuronal populations, which manifests symptomatically as cognitive and/or motor impairments. Until recently, most treatments for these disorders have targeted single aspects of disease pathology; however, this strategy has proved largely ineffective, and focus has now turned towards therapeutics which target multiple aspects underlying neurodegeneration. Anthocyanins are unique flavonoid compounds that have been shown to modulate several of the factors contributing to neuronal death, and interest in their use as therapeutics for neurodegeneration has grown in recent years. Additionally, due to observations that the bioavailability of anthocyanins is low relative to that of their metabolites, it has been proposed that anthocyanin metabolites may play a significant part in mediating the beneficial effects of an anthocyanin-rich diet. Thus, in this review, we will explore the evidence evaluating the neuroprotective and therapeutic potential of anthocyanins and their common metabolites for treating neurodegenerative diseases.

Antioxidant Effect of Flavonoids Present in Euterpe oleracea Martius and Neurodegenerative Diseases: A Literature Review

INTRODUCTION

Neurodegenerative diseases (NDDs) are progressive, directly affecting the central nervous system (CNS), the most common and recurrent are Alzheimer's disease (AD) and Parkinson's disease (PD). One factor frequently mentioned in the etiology of NDDs is the generation of free radicals and oxidative stress, producing cellular damages. Studies have shown that the consumption of foods rich in polyphenols, especially those of the flavonoid class, has been related to the low risk in the development of several diseases. Due to the antioxidant properties present in the food, a fruit that has been gaining prominence among these foods is the Euterpe oleracea Mart. (açaí), because it presents in its composition significant amounts of a subclass of the flavonoids, the anthocyanins.

METHODS

In the case review, the authors receive a basic background on the most common NDDs, oxidative stress and antioxidants. In addition, revisiting the various studies related to NDDs, including flavonoids and consumption of açaí.

RESULTS

Detailed analysis of the recently reported case studies reveal that dietary consumption of flavonoid-rich foods, such as açaí fruits, suggests the efficacy to attenuate neurodegeneration and prevent or reverse the age-dependent deterioration of cognitive function.

CONCLUSION

This systematic review points out that flavonoids presenting in açaí have the potential for the treatment of diseases such as PD and AD and are candidates for drugs in future clinical research. However, there is a need for in vitro and in vivo studies with polyphenol that prove and ratify the therapeutic potential of this fruit for several NDDs.

The value of the Brazilian açai fruit as a therapeutic nutritional strategy for chronic kidney disease patients

Açai (Euterpe oleracea Mart.) fruit from the Amazon region in Brazil contains bioactive compounds such as α-tocopherol, anthocyanins (cyanidin 3-glycoside and cyanidin 3-rutinoside), and other flavonoids with antioxidant and anti-inflammatory properties. Moreover, the prebiotic activity of anthocyanins in modulating the composition of gut microbiota has emerged as an additional mechanism by which anthocyanins exert health-promoting effects. Açai consumption may be a nutritional therapeutic strategy for chronic kidney disease (CKD) patients since these patients present with oxidative stress, inflammation, and dysbiosis. However, the ability of açai to modulate these conditions has not been studied in CKD, and this review presents recent information about açai and its possible therapeutic effects in CKD.

Subchronic treatment with acai frozen pulp prevents the brain oxidative damage in rats with acute liver failure

Acai has been used by the population due to its high nutritional value and its benefits to health, such as its antioxidant properties. The aim of this study was to evaluate the protective effect of acai frozen pulp on oxidative stress parameters in cerebral cortex, hippocampus and cerebellum of Wistar rats treated with carbon tetrachloride (CCl₄). Thirty male Wistar rats (90-day-old) were orally treated with water or acai frozen pulp for 14 days (7 μL/g). On the 15th day, half of the animals received treatment with mineral oil and the other half with CCl₄ (3.0 mL/kg). The cerebral cortex, hippocampus and cerebellum were dissected and used for analysis of creatine kinase activity (CK), thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, and the activity of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Statistical analysis was performed by ANOVA followed by Tukey's post-test. CCl₄ was able to inhibit CK activity in all tissues tested and to provoke lipid damage in cerebral cortex and cerebellum, and protein damage in the three tissues tested. CCl₄ enhanced CAT activity in the cerebral cortex, and inhibited CAT activity in the hippocampus and cerebellum and reduced SOD activity in all tissues studied. Acai frozen pulp prevented the inhibition of CK, TBARS, carbonyl and CAT activity in all brain structures and only in hippocampus for SOD activity. Therefore, acai frozen pulp has antioxidant properties and maybe could be useful in the treatment of some diseases that affect the central nervous system that are associated with oxidative damage.

Carbon Tetrachloride Increases the Pro-inflammatory Cytokines Levels in Different Brain Areas of Wistar Rats: The Protective Effect of Acai Frozen Pulp

Acai offers health benefits associated with its high antioxidante capacity, phytochemical composition, nutritional and sensory value. Therefore, the objective of this study was to evaluate the protective effect of acai frozen pulp on carbon tetrachloride (CCl4)-induced damage via modulation of anti- and pro-inflammatory cytokines in rat brain tissue. The rats were treated via oral (gavage) daily with water or acai frozen pulp for 14 days at a dose of 7 μL/g. On the 15th day, the animals in each group received a single intraperitoneal injection of CCl4 in a dose of 3.0 mL/kg or the same volume of mineral oil. After 4 h, the animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were dissected and homogenated to evaluate the levels of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), interleukin 18 (IL-18), interleukin 6 (IL-6) and interleukin 10 (IL-10). Data were statistically analyzed by analysis of variance followed by the Tukey post hoc test. It was observed that CCl4 increased TNF-α, IL-1β and IL-18 levels in all brain tissues, and that acai frozen pulp was able to prevent this increase. IL-6 and IL-10 brain tissue levels remained unchanged during all treatments. CCl4 experimental model was suitable to investigate brain tissue anti and pro-inflammatory cytokines. Acai frozen pulp prevented an increase in IL-1β, IL-18 and TNF-α, while IL-6 and IL-10 levels remained unchanged. The precise pathway by which inflammation contribute to hepatic encephalopathy, as well as to how this pathway can be modulated, is still under investigation.

Amazon acai: chemistry and biological activities: a review

Acai (acai or assai) is one of the Amazon's most popular functional foods and widely used in the world. There are many benefits to its alleged use in the growing market for nutraceuticals. The acai extracts have a range of polyphenolic components with antioxidant properties, some of those present in greater quantity are orientin, isoorientin and vanillic acid, as well as anthocyanins cyanidin-3-glucoside and cyanidin-3-rutinoside. The presence of these substances is linked mainly to the antioxidant, anti- inflammatory, anti-proliferative and cardioprotective activities. Importantly, there are two main species of the Euterpe genus which produce acai. There are several differences between them but they are still quite unknown, from literature to producers and consumers. In this review are highlighted the chemical composition, botanical aspects, pharmacological, marketing and nutrition of these species based on studies published in the last five years in order to unify the current knowledge and dissimilarities between them.

In vitro antioxidant capacity of tea of Echinodorus grandiforus, “leather hat,” in Wistar rat liver

Oxidative stress has been considered as one of the factors responsible for hepatic diseases, which sometimes require new ways of treatment. The present study aimed to evaluate the in vitro antioxidant capacity of the tea of Echinodorus grandiforus (“leather hat” plant) in rat liver. Different preparations of tea were evaluated for phenolic composition, antioxidant activity by DPPH assay and ability to inhibit lipid peroxidation induced by copper sulfate. The antioxidant activity was assessed in liver tissue treated with sodium azide in the presence or absence of tea by assays for lipid peroxidation (TBARS), protein oxidation (carbonyl) and the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). The results show that different preparations of tea are important sources of polyphenols and contain theobromine, catechin and vitexin. Furthermore, the results indicate that this tea exhibits an antioxidant activity by its ability to scavenge DPPH radical. Different preparations of tea prevented damage to lipids and proteins induced by sodium azide, as well as assisting in restoring CAT and SOD activities. Thus, it can be seen that E. grandiforus tea had antioxidant activity in serum and liver being able to prevent oxidative damages generated by sodium azide.

Aerobic exercise and not a diet supplemented with jussara açaí (Euterpe edulis Martius) alters hepatic oxidative and inflammatory biomarkers in ApoE-deficient mice

The pulp of jussara açaí (Euterpe edulis Martius) fruit is rich in anthocyanins that exert antioxidant and anti-inflammatory effects similar to those exerted by aerobic exercise. In the present study, we investigated the effects of jussara açaí fruit pulp consumption, either alone or in combination with aerobic exercise, on the hepatic oxidative and inflammatory status of ApoE-deficient (ApoE - / - ) mice. Male mice were divided into four groups (control (C), control plus açaí, exercise plus açaí (EXA) and exercise (EX)) and fed the AIN-93M diet or the AIN-93M diet formulated to contain 2 % freeze-dried açaí pulp. Mice in the EX and EXA groups were subjected to a progressive running programme (5 d/week, 60 min/d, 16 m/min) for 12 weeks. Mice that were made to exercise exhibited reduced (40·85 %; P< 0·05) hepatic superoxide dismutase activity when compared with the C mice, independent of the açaí diet. Mice in the EX group exhibited a lower (42 %; P< 0·05) mRNA expression of monocyte chemotactic protein-1 in the liver compared with the C mice. Mice in the EXA and EX groups had lower percentages of hepatic lipid droplets (70 % and 56 %, respectively; P< 0·05) when compared with the C mice. Mice in the EX group had smaller (58 %; P< 0·05) area of lesions in the aorta when compared with the C mice. Serum lipid profile was not affected (P>0·05). In conclusion, aerobic exercise training rather than açaí fruit pulp consumption or a combination of both enhances the hepatic oxidative and inflammatory status of ApoE - / - mice.

Açaí (Euterpe oleracea Mart.) modulates oxidative stress resistance in Caenorhabditis elegans by direct and indirect mechanisms

Açaí (Euterpe oleracea Mart.) has recently emerged as a promising source of natural antioxidants. Despite its claimed pharmacological and nutraceutical value, studies regarding the effects of açaí in vivo are limited. In this study, we use the Caenorhabditis elegans model to evaluate the in vivo antioxidant properties of açaí on an organismal level and to examine its mechanism of action. Supplementation with açaí aqueous extract (AAE) increased both oxidative and osmotic stress resistance independently of any effect on reproduction and development. AAE suppressed bacterial growth, but this antimicrobial property did not influence stress resistance. AAE-increased stress resistance was correlated with reduced ROS production, the prevention of sulfhydryl (SH) level reduction and gcs-1 activation under oxidative stress conditions. Our mechanistic studies indicated that AAE promotes oxidative stress resistance by acting through DAF-16 and the osmotic stress response pathway OSR-1/UNC-43/SEK-1. Finally, AAE increased polyglutamine protein aggregation and decreased proteasome activity. Our findings suggest that natural compounds available in AAE can improve the antioxidant status of a whole organism under certain conditions by direct and indirect mechanisms.

Anthocyanin-rich açaí (Euterpe oleracea Mart.) extract attenuates manganese-induced oxidative stress in rat primary astrocyte cultures

Manganese (Mn) is an essential element for human health. However, at high concentrations Mn may be neurotoxic. Mn accumulates in astrocytes, affecting their redox status. In view of the high antioxidant and anti-inflammatory properties of the exotic Brazilian fruit açaí (Euterpe oleracea Mart.), its methanolic extract was obtained by solid-phase extraction (SPE). This açaí extract showed considerable anthocyanins content and direct antioxidant capacity. The açaí extract scavenged 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH•) with an EC₅₀ of 19.1 ppm, showing higher antioxidant activity compared to butylated hydroxytoluene (BHT), but lower than ascorbic acid and quercetin. This obtained açaí extract also attenuated Mn-induced oxidative stress in primary cultured astrocytes. Specifically, the açaí extract at an optimal and nutritionally relevant concentration of 0.1 μg/ml prevented Mn-induced oxidative stress by (1) restoring GSH/GSSG ratio and net glutamate uptake, (2) protecting astrocytic membranes from lipid peroxidation, and (3) decreasing Mn-induced expression of erythroid 2-related factor (Nrf2) protein. A larger quantity of açaí extract exacerbated the effects of Mn on these parameters except with respect to lipid peroxidation assessed by means of F₂-isoprostanes. These studies indicate that at nutritionally relevant concentration, anthocyanins obtained from açaí protect astrocytes against Mn neurotoxicity, but at high concentrations, the "pro-oxidant" effects of its constituents likely prevail. Future studies may be profitably directed at potential protective effects of açaí anthocyanins in nutraceutical formulations.

Restoration of stressor-induced calcium dysregulation and autophagy inhibition by polyphenol-rich açaí (Euterpe spp.) fruit pulp extracts in rodent brain cells in vitro

OBJECTIVES

Oxidative damage to lipids, proteins, and nucleic acids in the brain often causes progressive neuronal degeneration and death that are the focal traits of chronic and acute pathologies, including those involving cognitive decline. The aim of this study was to investigate the specific effects of both Euterpe oleracea and Euterpe precatoria açaí fruit pulp on restoring stressor-induced calcium dysregulation, stunted growth of basal dendrites, and autophagy inhibition using embryonic hippocampal and HT22 hippocampal neurons.

METHODS

Water-soluble whole fruit pulp extracts from two açaí species were applied to rat primary neurons and HT22 hippocampal neurons with varied time and concentrations. Recovery of neurons from dopamine-induced Ca(2+) dysregulation was measured by live cell imaging using fluorescent microscopy. The effect of açaí fruit pulp extracts on neurons following chemically-induced autophagy inhibition was measured using both immunofluorescence and immunohistochemical techniques.

RESULTS

It has been postulated that at least part of the loss of cognitive function in aging may depend on a dysregulation in calcium ion (Ca(2+)) homeostasis and a loss of autophagy function in the brain, which affects numerous signaling pathways and alters protein homeostasis. In the present study, polyphenol-rich fruit pulp extracts from two species of açaí, Euterpe precatoria and Euterpe oleracea, when applied to rat hippocampal primary neuronal cells (E18), caused a significant (P < 0.05) recovery of depolarized brain cells from dopamine-induced Ca(2+) influx. Autophagy, a protein homeostasis mechanism in brain, when blocked by known inhibitors such as bafilomycin A1 or wortmannin, caused a significant reduction in the growth of primary basal dendrites in rodent primary hippocampal neurons and significant accumulation of polyubiquitinated proteins in mouse HT22 hippocampal neurons in culture. However, pretreatment with açaí extracts up to 1 mg/mL significantly increased the length of basal dendrites and attenuated the inhibitor-induced autophagy dysfunction. Açaí extracts activated the phosphorylation of mammalian target of rapamycin, increased the turnover of autophagosomes and MAP1 B LC3-II, and decreased accumulation of LC3-ubiquitin binding P62/SQSTM1.

CONCLUSION

Although the polyphenol profile of Euterpe precatoria showed substantially higher concentrations of major flavonoids han Euterpe oleracea, the relative effects were essentially similar for both species. The study adds to growing evidence that supports the putative health effects of açaí fruit species on brain cells.

Nasal Acai polysaccharides potentiate innate immunity to protect against pulmonary Francisella tularensis and Burkholderia pseudomallei Infections

Pulmonary Francisella tularensis and Burkholderia pseudomallei infections are highly lethal in untreated patients, and current antibiotic regimens are not always effective. Activating the innate immune system provides an alternative means of treating infection and can also complement antibiotic therapies. Several natural agonists were screened for their ability to enhance host resistance to infection, and polysaccharides derived from the Acai berry (Acai PS) were found to have potent abilities as an immunotherapeutic to treat F. tularensis and B. pseudomallei infections. In vitro, Acai PS impaired replication of Francisella in primary human macrophages co-cultured with autologous NK cells via augmentation of NK cell IFN-γ. Furthermore, Acai PS administered nasally before or after infection protected mice against type A F. tularensis aerosol challenge with survival rates up to 80%, and protection was still observed, albeit reduced, when mice were treated two days post-infection. Nasal Acai PS administration augmented intracellular expression of IFN-γ by NK cells in the lungs of F. tularensis-infected mice, and neutralization of IFN-γ ablated the protective effect of Acai PS. Likewise, nasal Acai PS treatment conferred protection against pulmonary infection with B. pseudomallei strain 1026b. Acai PS dramatically reduced the replication of B. pseudomallei in the lung and blocked bacterial dissemination to the spleen and liver. Nasal administration of Acai PS enhanced IFN-γ responses by NK and γδ T cells in the lungs, while neutralization of IFN-γ totally abrogated the protective effect of Acai PS against pulmonary B. pseudomallei infection. Collectively, these results demonstrate Acai PS is a potent innate immune agonist that can resolve F. tularensis and B. pseudomallei infections, suggesting this innate immune agonist has broad-spectrum activity against virulent intracellular pathogens.

Anthocyanin-rich açai (Euterpe oleracea Mart.) fruit pulp fractions attenuate inflammatory stress signaling in mouse brain BV-2 microglial cells

Age-related diseases of the brain compromise memory, learning, and movement and are directly linked with increases in oxidative stress and inflammation. Previous research has shown that supplementation with berries can modulate signaling in primary hippocampal neurons or BV-2 mouse microglial cells. Because of their high polyphenolic content, fruit pulp fractions of açai ( Euterpe oleracea Mart.) were explored for their protective effect on BV-2 mouse microglial cells. Freeze-dried açai pulp was fractionated using solvents with different polarities and analyzed using HPLC for major anthocyanins and other phenolics. Fractions extracted using methanol (MEOH) and ethanol (ETOH) were particularly rich in anthocyanins such as cyanidin, delphinidin, malvidin, pelargonidin, and peonidin, whereas the fraction extracted using acetone (ACE) was rich in other phenolics such as catechin, ferulic acid, quercetin, resveratrol, and synergic and vanillic acids. Studies were conducted to investigate the mitigating effects of açai pulp extracts on lipopolysaccharide (LPS, 100 ng/mL) induced oxidative stress and inflammation; treatment of BV-2 cells with acai fractions resulted in significant (p < 0.05) decreases in nitrite production, accompanied by a reduction in inducible nitric oxide synthase (iNOS) expression. The inhibition pattern was emulated with the ferulic acid content among the fractions. The protection of microglial cells by açai pulp extracts, particularly that of MEOH, ETOH, and ACE fractions, was also accompanied by a significant concentration-dependent reduction in cyclooxygenase-2 (COX-2), p38 mitogen-activated protein kinase (p38-MAPK), tumor necrosis factor-α (TNFα), and nuclear factor κB (NF-κB). The current study offers valuable insights into the protective effects of açai pulp fractions on brain cells, which could have implications for improved cognitive and motor functions.

Exotic Fruits as Therapeutic Complements for Diabetes, Obesity and Metabolic Syndrome

The prevalence and severity of obesity, type 2-diabetes, and the resultant metabolic syndrome are rapidly increasing. As successful preventive and therapeutic strategies for these life-threatening health ailments often come with adverse side effects, nutritional elements are widely used in many countries as preventive therapies to prevent or manage metabolic syndrome. Fruits are important dietary components, and contain various bioactive constituents. Many of these constituents have been proven to be useful to manage and treat various chronic diseases such as diabetes, obesity, cancer and cardiovascular diseases. Although exotic fruits are understudied throughout the world due to their limited regional presence, many studies reveal their potent ability to ameliorate metabolic derangements and the resultant conditions i.e. diabetes and obesity. The aim of this article is to review the role of exotic fruits and their constituents in the regulation of metabolic functions, which can beneficially alter diabetes and obesity pathophysiology.

Dietary açai modulates ROS production by neutrophils and gene expression of liver antioxidant enzymes in rats

Açai (Euterpe oleracea Mart.) has recently emerged as a promising source of natural antioxidants. Because increased oxidative stress and impaired antioxidant defense mechanisms are important factors in the development of diabetic complications and many health claims have been reported for açai, the present study was undertaken to evaluate the possible protective effects of açai on the production of reactive oxygen species by neutrophils and on the liver antioxidant defense system in control and streptozotocin-induced diabetic rats. Diet supplementation with 2% açai was found to increase mRNA levels for gamma-glutamylcysteine synthetase and glutathione peroxidase in liver tissue and to decrease reactive oxygen species production by neutrophils. Compared to control animals, diabetic rats exhibited lower levels of mRNA coding for Zn-superoxide dismutase, glutathione peroxidase and gamma-glutamylcysteine synthetase and higher levels of reactive oxygen species production by neutrophils, thiobarbituric acid-reactive substances and carbonyl proteins in hepatic tissues. Although açai supplementation was not effective in restore gene expression of antioxidant enzymes in diabetic rats, it showed a protective effect, decreasing thiobarbituric acid-reactive substances levels and increasing reduced glutathione content in the liver. These findings suggest that açai can modulate reactive oxygen species production by neutrophils and that it has a significant favorable effect on the liver antioxidant defense system under fisiological conditions of oxidative stress and partially revert deleterious effects of diabetes in the liver.

Flavonoids from acai (Euterpe oleracea Mart.) pulp and their antioxidant and anti-inflammatory activities

Five flavonoids, (2S,3S)-dihyrokaempferol 3-O-β-d-glucoside (1) and its isomer (2R,3R)-dihydrokaempferol 3-O-β-d-glucoside (2) , isovitexin (3), velutin (4) and 5,4'-dihydroxy-7,3',5'-trimethoxyflavone (5), were isolated from acai (Euterpe oleracea Mart.) pulp. The structures of these compounds were elucidated based upon spectroscopic and chemical analyses. To our knowledge, compounds 1, 2, 4 and 5 were identified from acai pulp for the first time. The in vitro antioxidant activities of these compounds were evaluated by the oxygen radial absorbance capacity (ORAC) assay. The ORAC values varied distinctly (4458.0-22404.5μmol Trolox equivalent (TE)/g) from 5,4'-dihydroxy-7,3',5'-trimethoxyflavone (5) to isovitexin (3) and were affected by the numbers/positions of hydroxyl groups, substitute groups, as well as stereo configuration. The anti-inflammatory effects of these compounds were screened by the secreted embryonic alkaline phosphatase (SEAP) reporter assay, which is designed to measure NF-κB activation. Velutin (4) was found to dose-dependently inhibit SEAP secretion in RAW-blue cells induced by LPS, with an IC50 value of 2.0μM. Velutin (4) also inhibited SEAP secretion induced by oxidised LDL, indicating potential athero-protective effects.

Flavan-3-ol compounds from wine wastes with in vitro and in vivo antioxidant activity

It has been suggested that the dietary intake of antioxidant supplements could be a useful strategy to reduce the incidence of diseases associated with oxidative stress. The aim of present work is to study the possibility to obtain compounds with antioxidant activity from wine wastes using water as solvent. Results have shown that it is possible to obtain flavan-3-ol compounds from wine wastes both from V. vinifera (cv. Cabernet Sauvignon and Merlot) and V. labrusca (cv. Bordo and Isabella) species. The main phenolic compounds found in the extracts were catechin and epicatechin, followed by procyanidin B3, procyanidin B1, procyanidin B2, gallic acid, epigallocatechin, and procyanidin B4. All flavan-3-ol extracts showed significant in vitro and in vivo activities. It was found that the extracts were able to prevent lipid and protein oxidative damage in the cerebral cortex, cerebellum and hippocampus tissues of rats. Although further studies are necessary, these flavan-3-ol extracts show potential to be used to reduce the incidence of degenerative diseases associated with oxidative stress.

Safety evaluation of an açai-fortified fruit and berry functional juice beverage (MonaVie Active(®))

The safety of an açai (Euterpe oleracea Mart.) pulp enriched fruit and berry juice, MonaVie Active®, fortified with the functional ingredient, glucosamine, was studied. The beverage was found not to be mutagenic, clastogenic, cytotoxic, or genotoxic, as determined by the bacterial reverse mutation assay, chromosomal aberration assay, mouse micronucleus assay, and mammalian cell gene mutation (L5178Y) assay. The single dose LD50 based on a 14-day acute oral toxicity study is greater than 20,000 mg/kg bw, the highest dose tested. In a repeat dose 90-day oral subchronic toxicity study by gavage, 220 animals were randomly assigned to a control group, an untreated group, or one of three experimental groups (10, 20 and 40 g/kg bw). No treatment-related significant changes in body weight, food and water consumption, ophthalmology, organ weights, urinanalysis, hematological and clinical chemistry, or gross pathology, were observed in surviving animals compared to the control groups. Three animals died midway through the observation period (male, 20 g/kg bw/day; male 40 g/kg bw/day; and, female, 10 g/kg bw/day). These animals died without preceding clinical symptoms, histopathological lesions, or evidence of injury to tissue or organs except for signs of suffocation/aspiration congestion, which was concluded to be due to problems with the gavage administration of the fluid test article, and not due to the test article itself. The NOEAL was determined to be 40 g/kg bw/day for male and female rats, which was the highest dose tested. Phylloquinone (vitamin K1) content averaged 21.7 μg/100 g, comparable to amounts found in iceberg lettuce. In conclusion, the results provide additional experimental evidence that MonaVie Active® juice is non-toxic.