Effects of banana, orange, and apple on oxidative stress-induced neurotoxicity in PC12 cells

The role of oral antioxidants in the improvement of sperm parameters in infertile men

PURPOSE

A variety of pathologic conditions may increase oxidative stress in semen resulting in structural modifications to spermozoa's plasma membrane that interfere with sperm motility, morphology, and count. Antioxidants are currently being marketed to treat male infertility. In semen, antioxidants may decrease oxidative stress and potentially improve sperm parameters. In this narrative, mini-review we evaluated the effectiveness of antioxidants in infertility.

METHODS

This mini-review of the current literature has been carried out through searching of the PubMed and Google scholar databases.

RESULTS AND CONCLUSIONS

The literature review suggests that there is evidence that oral antioxidants such as selenium, carnitine, zinc, coenzymeQ10, vitamins E and C, etc. alone or in combinations, improve sperm count, motility, morphology as well as pregnancy rates in infertile men with idiopathic oligoasthenospermia. Unfortunately, most of these studies are poorly designed, limited by sample size, varying in dosage, differing in primary end points, and most notably lacking live birth data. Importantly, large randomized, well-designed, placebo-controlled trials are needed.

Potential of Sorghum Polyphenols to Prevent and Treat Alzheimer's Disease: A Review Article

Alzheimer's disease (AD) is characterized by the excessive deposition of extracellular amyloid-beta peptide (Aβ) and the build-up of intracellular neurofibrillary tangles containing hyperphosphorylated tau proteins. This leads to neuronal damage, cell death and consequently results in memory and learning impairments leading to dementia. Although the exact cause of AD is not yet clear, numerous studies indicate that oxidative stress, inflammation, and mitochondrial dysfunction significantly contribute to its onset and progression. There is no effective therapeutic approach to stop the progression of AD and its associated symptoms. Thus, early intervention, preferably, pre-clinically when the brain is not significantly affected, is a better option for effective treatment. Natural polyphenols (PP) target multiple AD-related pathways such as protecting the brain from Aβ and tau neurotoxicity, ameliorating oxidative damage and mitochondrial dysfunction. Among natural products, the cereal crop sorghum has some unique features. It is one of the major global grain crops but in the developed world, it is primarily used as feed for farm animals. A broad range of PP, including phenolic acids, flavonoids, and condensed tannins are present in sorghum grain including some classes such as proanthocyanidins that are rarely found in others plants. Pigmented varieties of sorghum have the highest polyphenolic content and antioxidant activity which potentially makes their consumption beneficial for human health through different pathways such as oxidative stress reduction and thus the prevention and treatment of neurodegenerative diseases. This review summarizes the potential of sorghum PP to beneficially affect the neuropathology of AD.

Granny Smith Apple Extract Lowers Inflammation and Improves Antioxidant Status in L-arginine-induced Exocrine Pancreatic Dysfunction in Rats

Objectives

Granny Smith is a cultivated hybrid variety of apple with a high antioxidant content relative to all other species of apple. Acute pancreatitis (AP) is an instantly emerging inflammatory condition with a high mortality rate. The preferred treatment is restricted to symptomatic relief and supportive care. The present study was undertaken to evaluate the favorable effects of Granny Smith apple extract (GSAE) as a prophylactic treatment for L-arginine-induced AP in rats.

Materials and Methods

Male Sprague Dawley rats were divided in to five groups (n=6): Normal control (saline), disease control (a single dose of L-arginine 2.5 g/kg I.P.), positive control (pelatonin 10 mg/kg I.P.), and GSAE I and II (200 mg/kg and 400 mg/kg, orally, respectively). All groups were treated for 7 days. At the end of the study, blood samples were collected from the retro-orbital plexus, serum separated, and subjected to estimation of biomarker enzymes such as amylase, lipase, antioxidant enzymes, etc. The animals were then sacrificed, and the pancreas was isolated and subjected to estimation of tissue biomarkers, DNA fragmentation assay, and histopathological studies.

Results

Serum levels of amylase and lipase were significantly (p<0.001) reduced in L-arginine-treated rats. Similar results were also observed with tissue inflammatory markers such as malondialdehyde, nitrate, etc. There was a dramatic increase (p<0.001) in the overall antioxidant enzyme levels when compared with disease control rats. Histopathological examination of pancreatic tissue showed an intact structural feature of acinar cells in the extract-treated group of rats, which was further in pact with the intact DNA found in the DNA fragmentation assay.

Conclusion

Thus, GSAE treatment was found to be beneficial in lowering the inflammatory conditions of AP by improving the overall antioxidant levels, and a further investigation into its exact molecular mechanism is needed.

Ultrasound stress compromises the correlates of emotional-like states and brain AMPAR expression in mice: effects of antioxidant and anti-inflammatory herbal treatment

The modern lifestyle is associated with exposure to "psychological" or "emotional" stress. A growing portion of the population is exposed to emotional stress that results in a high incidence of anxiety disorders, a serious social problem. With this rise, there is a need for understanding the neurobiological causes of stress-induced anxiety and to offer safe remedies for this condition. Side effects of existing pharmaceuticals necessitate the search for alternatives. Having fewer adverse effects than classic remedies, natural extract-based therapies can be a promising solution. Here, we applied a model of emotional stress in BALB/c mice using ultrasound exposure to evoke the signs of anxiety-like behavior. We examined the behavioral and molecular impact of ultrasound and administration of herbal antioxidant/anti-inflammatory treatment (HAT) on AMPA receptor expression, markers of plasticity, inflammation and oxidative stress. A 3-week ultrasound exposure increased scores of anxiety-like behaviors in the standard tests and altered hippocampal expression as well as internalization of AMPA receptor subunits GluA1-A3. Concomitant treatment with HAT has prevented increases of anxiety-like behaviors and other behavioral changes, normalized hippocampal malondialdehyde content, GSK3β and pro-inflammatory cytokines Il-1β and Il-6, and the number of Ki67-positive cells. Levels of malondialdehyde, a common measure of oxidative stress, significantly correlated with the investigated end-points in stressed, but not in non-stressed animals. Our results emphasize the role of oxidative stress in neurobiological abnormalities associated with experimentally induced condition mimicking emotional stress in rodents and highlight the potential therapeutic use of anti-oxidants like herbal compositions for management of stress-related emotional disturbances within the community.

Antioxidant Capacity of Thistle (Cirsium japonicum) in Various Drying Methods and their Protection Effect on Neuronal PC12 Cells and Caenorhabditis elegans

The aim of this study was, firstly, to evaluate the phenol profile of thistle (Cirsium japonicum, CJ) by High performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS), dried by different methods (90 °C hot-air, 70 °C hot-air, shade-, and freeze-drying). Secondly, we aimed to evaluate the relationship between phenolic compounds content and antioxidant properties. CJ contained chlorogenic acid, linarin, and pectolinarin. Total phenolic contents of CJ significantly decreased under hot-air-drying condition, especially chlorogenic acid contents in CJ have been reduced by 85% and 60% for 90 °C and 70 °C hot-air-drying, respectively. We evaluated the protective effect on adrenal pheochromocytoma (PC12) cells and Caenorhabditis elegans using shade-dried CJ, which has the largest phenolic contents and the strongest antioxidant property. CJ-treated PC 12 cells dose-dependently exhibited the protective effects against reactive oxygen species (ROS), while cell viability increases, lactate dehydrogenase release decreases, and ROS formation decreases. Furthermore, CJ has also shown protection against ROS in C. elegans. Consequently, CJ contributed to lifespan extension under ROS stress without influencing the physiological growth.

Effect and mechanism of oyster hydrolytic peptides on spatial learning and memory in mice

Oysters (Crassostrea talienwhanensis) contain large amounts of protein and exhibit many biological activities. This study was aimed at preparing oyster protein hydrolysates (OPH) and evaluating the OPH based on a spatial learning and memory capacity. A response surface methodology was employed to optimize hydrolysis conditions to determine the OPH with the highest AChE inhibitory activity, and the optimum extraction conditions were as follows: enzyme concentration of 1444.88 U g-1, pH of 7.38, extraction temperature of 45 °C, extraction time of 5.56 h and a water/material ratio of 2.45 : 1, and the minimum acetylcholinesterase (AChE) activity was 0.069 mM min-1. The spatial memory and learning abilities and passive avoidance in mice were determined by using the Morris water maze test and a dark/light avoidance test. Furthermore, the OPH group could relieve oxidative stress, reduce AChE levels, increase choline acetyltransferase (ChAT) levels and alleviate inflammatory reaction through reduction of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels. Additionally, up-regulated expressions of brain-derived neurotrophic factor (BDNF) and neural cell adhesion molecules (NCAM) were observed in mice treated with OPH. These findings suggested that OPH could be a functional food candidate to improve the learning and memory ability associated with oxidative stress and inflammatory reactions.

Protective effect of captopril against diazinon induced nephrotoxicity and neurotoxicity via inhibition of ROS-NO pathway

Diazinon (Dz) is a widely used insecticide. It can induce nephrotoxicity and neurotoxicity via oxidative stress. Captopril, an angiotensin-converting enzyme inhibitor, is known for its antioxidant properties. In this study, we used captopril for ameliorating of Dz-induced kidney and brain toxicity in rats. Animals were divided into five groups as follows: negative control (olive oil), Dz (150 mg kg^-1), captopril (60 and 100 mg kg^-1) and positive control (N-acetylcysteine 200 mg kg^-1) were injected intraperitoneally 30 min before Dz. After 24 h, animals were anesthetized and the brain and kidney tissues were separated. Then oxidative stress factors were evaluated. Also, blood was collected for assessment of blood urea nitrogen (BUN), creatinine (Cr) and nitric oxide (NO) levels. Dz significantly increased oxidative stress markers such as reactive oxygen species (ROS), lipid peroxidation, and protein carbonyl as well as glutathione (GSH) oxidation in both tissues. Increased levels of the BUN, Cr and NO were observed after Dz injection. Interestingly, captopril administration significantly decreased ROS production in both tissues. Captopril significantly protected kidney and brain against lipid peroxidation and GSH oxidation. Administration of captopril could markedly inhibit protein carbonyl production in kidney and brain after Dz injection. Furthermore, captopril ameliorated the increased level of BUN, Cr and NO. These results suggested that captopril can prevent Dz-induced oxidative stress, nephrotoxicity and neurotoxicity because of its antioxidant activity.

Changes in polyphenol composition and bioactivity of the native Chilean white strawberry (Fragaria chiloensis spp. chiloensis f. chiloensis) after in vitro gastrointestinal digestion

The Chilean white strawberry (Fragaria chiloensis spp. chiloensis f. chiloensis) is a semi-domesticated strawberry with high polyphenol content and antioxidant activity occurring in southern Chile. The aim of this work was to compare the composition and bioactivity of the polyphenol-enriched fruit extract (PEE) before and after simulated gastrointestinal digestion (GID). Results show a decrease by >50% in the total phenolic (TP) content at the end of the GID, compared to the non-digested PEE. A reduction in the antioxidant capacity of the PEEs was observed after GID by means of DPPH, FRAP, TEAC and anion superoxide assays. After simulated GID the PEE significantly inhibited α-glucosidase with an IC₅₀ value of 3.13μg/mL. The inhibition of pancreatic lipase was reduced by 95% after GID. All the PEEs did not show inhibitory effect towards α-amylase throughout the GID. In the same way, the PEEs did not significantly protect human gastric adenocarcinoma (AGS) cells against H₂O₂-induced stress. Thirty eight compounds were tentatively identified in the non-digested PEE. The compounds that were more affected by the simulated GID were simple phenolics. After the GID, only 33 and 25 compounds were detected, in the gastric and intestinal steps, respectively. These results evidence the changes elicited by GID on the bioactivity and polyphenolic composition of the white strawberry.

Linking lipid peroxidation and neuropsychiatric disorders: focus on 4-hydroxy-2-nonenal

4-hydroxy-2-nonenal (HNE) is considered to be a strong marker of oxidative stress; the interaction between HNE and cellular proteins leads to the formation of HNE-protein adducts able to alter cellular homeostasis and cause the development of a pathological state. By virtue of its high lipid concentration, oxygen utilization, and the presence of metal ions participating to redox reactions, the brain is highly susceptible to the formation of free radicals and HNE-related compounds. A variety of neuropsychiatric disorders have been associated with elevations of HNE concentration. For example, increased levels of HNE were found in the cortex of bipolar and schizophrenic patients, while HNE plasma concentrations resulted high in patients with major depression. On the same line, high brain concentrations of HNE were found associated with Huntington's inclusions. The incidence of high HNE levels is relevant also in the brain and cerebrospinal fluid of patients suffering from Parkinson's disease. Intriguingly, in this case the increase of HNE was associated with an accumulation of iron in the substantia nigra, a brain region highly affected by the pathology. In the present review we recapitulate the findings supporting the role of HNE in the pathogenesis of different neuropsychiatric disorders to highlight the pathogenic mechanisms ascribed to HNE accumulation. The aim of this review is to offer novel perspectives both for the understanding of etiopathogenetic mechanisms that remain still unclear and for the identification of new useful biological markers. We conclude suggesting that targeting HNE-driven cellular processes may represent a new more efficacious therapeutical intervention.

Reversal of Trimethyltin-Induced Learning and Memory Deficits by 3,5-Dicaffeoylquinic Acid

The antiamnesic effect of 3,5-dicaffeoylquinic acid (3,5-diCQA) as the main phenolic compound in Artemisia argyi H. extract on cognitive dysfunction induced by trimethyltin (TMT) (7.1 μg/kg of body weight; intraperitoneal injection) was investigated in order to assess its ameliorating function in mice. In several behavioral tests, namely, the Y-maze, passive avoidance, and Morris water maze (MWM) test, 3,5-diCQA significantly ameliorated learning and memory deficits. After the behavioral tests, brain tissues from the mice were analyzed to characterize the basis of the neuroprotective effect. Acetylcholine (ACh) levels increased, whereas the activity of acetylcholinesterase (AChE) decreased upon administration of 3,5-diCQA. In addition, 3,5-diCQA effectively protected against an increase in malondialdehyde (MDA) content, an increase in the oxidized glutathione (GSH) ratio, and a decline of total superoxide dismutase (SOD) level. 3,5-diCQA may prevent neuronal apoptosis through the protection of mitochondrial activities and the repression of apoptotic signaling molecules such as p-Akt, BAX, and p-tau (Ser 404).

Exogenous antioxidants--Double-edged swords in cellular redox state: Health beneficial effects at physiologic doses versus deleterious effects at high doses

The balance between oxidation and antioxidation is believed to be critical in maintaining healthy biological systems. Under physiological conditions, the human antioxidative defense system including e.g., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH) and others, allows the elimination of excess reactive oxygen species (ROS) including, among others superoxide anions (O₂^.-), hydroxyl radicals (OH.), alkoxyl radicals (RO.) and peroxyradicals (ROO.). However, our endogenous antioxidant defense systems are incomplete without exogenous originating reducing compounds such as vitamin C, vitamin E, carotenoids and polyphenols, playing an essential role in many antioxidant mechanisms in living organisms. Therefore, there is continuous demand for exogenous antioxidants in order to prevent oxidative stress, representing a disequilibrium redox state in favor of oxidation. However, high doses of isolated compounds may be toxic, owing to prooxidative effects at high concentrations or their potential to react with beneficial concentrations of ROS normally present at physiological conditions that are required for optimal cellular functioning. This review aims to examine the double-edged effects of dietary originating antioxidants with a focus on the most abundant compounds, especially polyphenols, vitamin C, vitamin E and carotenoids. Different approaches to enrich our body with exogenous antioxidants such as via synthetic antioxidants, diets rich in fruits and vegetables and taking supplements will be reviewed and experimental and epidemiological evidences discussed, highlighting that antioxidants at physiological doses are generally safe, exhibiting interesting health beneficial effects.

ACEMg Diet Supplement Modifies Progression of Hereditary Deafness

Dietary supplements consisting of beta-carotene (precursor to vitamin A), vitamins C and E and the mineral magnesium (ACEMg) can be beneficial for reducing hearing loss due to aminoglycosides and overstimulation. This regimen also slowed progression of deafness for a boy with GJB2 (CONNEXIN 26) mutations. To assess the potential for treating GJB2 and other forms of hereditary hearing loss with ACEMg, we tested the influence of ACEMg on the cochlea and hearing of mouse models for two human mutations: GJB2, the leading cause of childhood deafness, and DIAPH3, a cause of auditory neuropathy. One group of mice modeling GJB2 (Gjb2-CKO) received ACEMg diet starting shortly after they were weaned (4 weeks) until 16 weeks of age. Another group of Gjb2-CKO mice received ACEMg in utero and after weaning. The ACEMg diet was given to mice modeling DIAPH3 (Diap3-Tg) after weaning (4 weeks) until 12 weeks of age. Control groups received food pellets without the ACEMg supplement. Hearing thresholds measured by auditory brainstem response were significantly better for Gjb2-CKO mice fed ACEMg than for the control diet group. In contrast, Diap3-Tg mice displayed worse thresholds than controls. These results indicate that ACEMg supplementation can influence the progression of genetic hearing loss.

Antioxidant activity and phenolic profiles of the wild currant Ribes magellanicum from Chilean and Argentinean Patagonia

The Patagonian currant Ribes magellanicum is highly valued due to its pleasant flavor and sweet taste. The aim of this study was to characterize its constituents and to assess their antioxidant and cytoprotective properties. For the fruit phenolic‐enriched extract (PEE), total phenolics (TP), total flavonoids (TF), and antioxidant activity (DPPH, Ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant activity (TEAC)) were determined. Argentinean samples presented better activity in the DPPH and FRAP assays. Best cytoprotection against oxidative stress induced by H₂O₂ in AGS cells was found in one Argentinean sample at 500 μg mL⁻¹ (65.7%). HPLC MS/MS analysis allowed the tentative identification of 59 constituents, including eight anthocyanins, 11 conjugates of caffeic‐, ferulic‐, and coumaric acid, and 38 flavonoids, most of them quercetin and kaempferol derivatives. Argentinean samples showed a more complex pattern of anthocyanins, hydroxycinnamic acids (HCA), and flavonoids. Cyanidin rhamnoside hexoside and cyanidin hexoside were the main anthocyanins, accounting for 35 and 55% for the Argentinean and 60 and 27% for the ripe Chilean fruits. HCA content was about three times higher in Argentinean samples. The phenolic profiles of Chilean and Argentinean Ribes magellanicum show remarkable differences in chemical composition with higher HCA and flavonoid content in Argentinean samples.

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.

Antioxidant and neuronal cell protective effects of columbia arabica coffee with different roasting conditions

In vitro antioxidant activities and neuronal cell protective effects of ethanol extract from roasted coffee beans were investigated. Colombia arabica coffee (Coffea arabica) green beans were roasted to give medium (230°C, 10 min), city (230°C, 12 min) and french (230°C, 15 min) coffee beans. Total phenolics in raw green beans, medium, city and french-roasted beans were 8.81±0.05, 9.77±0.03, 9.92±0.04 and 7.76±0.01 mg of GAE/g, respectively. The content of 5-O-caffeoylquinic acid, the predominant phenolic, was detected higher in medium-roasted beans than others. In addition, we found that extracts from medium-roasted beans particularly showed the highest in vitro antioxidant activity on ABTS radical scavenging activity and FRAP assays. To determine cell viability using the MTT assay, extracts from medium-roasted beans showed higher protection against H₂O₂-induced neurotoxicity than others. Lactate dehydrogenase (LDH) leakage was also inhibited by the extracts due to prevention of lipid peroxidation using the malondialdehyde (MDA) assay from mouse whole brain homogenates. These data suggest that the medium-roasting condition to making tasty coffee from Columbia arabica green beans may be more helpful to human health by providing the most physiological phenolics, including 5-O-caffeoylquinic acids.

Epigallocatechin gallate attenuates L-DOPA-induced apoptosis in rat PC12 cells

In this study, the protective effects of EGCG on L-3,4-dihydroxyphenylalanine (L-DOPA)-induced oxidative cell death in catecholaminergic PC12 cells, the in vitro model of Parkinson's disease, were investigated. Treatment with L-DOPA at concentrations higher than 150 µM caused cytotoxicity in PC12 cells, as determined using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry detection. The apoptotic ratio was similar in cells treated with 100 µM EGCG plus 150 µM L-DOPA (5.02%) and the control (0.96%) (P > 0.05), and was lower than that of cells treated with L-DOPA only (32.24%, P < 0.05). The generation level of ROS (% of control) in cells treated with EGCG plus L-DOPA was lower than that in cells treated with L-DOPA only (123.90% vs 272.32%, P < 0.05). The optical density in production of TBARS in cells treated with L-DOPA only was higher than that in the control (0.27 ± 0.05 vs 0.08 ± 0.04, P < 0.05), and in cells treated with EGCG only (0.14 ± 0.02, P < 0.05), and EGCG plus L-DOPA (0.13 ± 0.02, P < 0.05). The intracellular level of GSH in cells treated with EGCG plus L-DOPA was higher than that in cells treated with L-DOPA only (233.25 ± 16.44 vs 119.23 ± 10.25, P < 0.05). These results suggest that EGCG protects against L-DOPA-induced oxidative apoptosis in PC12 cells, and might be a potent neuroprotective agent.

Regulation of nodularin-induced apoptosis by epigallocatechin-3-gallate on fish lymphocytes in vitro

Nodularin is one of the most conspicuous and widespread pollutants that elicit water ecological hazards to fish, causing serious damage on the immune system and physiological functions. Nodularin can cause oxidative stress-induced apoptosis on fish lymphocytes. The regulatory effects of epigallocatechin-3-gallate (EGCG) at 10, 100, and 1000 μg/L levels on the antioxidant defense system and apoptosis of Carassius auratus lymphocytes exposed to a high dose of nodularin (100 μg/L) were quantified in vitro. EGCG reduced nodularin-induced oxidative damage on fish immune cells. This compound significantly increased the activities of superoxide dismutase and catalase and the level of glutathione but decreased the levels of intracellular reactive oxygen species and malondialdehyde. Flow cytometry results showed that the percentages of apoptotic cells after treatment with 10, 100, and 1000 μg/L EGCG for 12 h reached 27.9%, 19.1%, and 13.7%, respectively. By contrast, the nodularin alone-induced group showed a high percentage of apoptosis (44.2%). Western blot analysis showed the increased expression of bcl-2 and the decreased expression of bax and caspase-3 in EGCG-treated fish lymphocytes. EGCG also inhibited the potential collapse of the mitochondrial membrane. Overall, EGCG can inhibit nodularin-induced apoptosis and protect the normal immunity of fish by regulating bax/bcl-2 and blocking the downstream of mitochondrial apoptosis pathway with increased intracellular antioxidant enzyme activity.

Antiamnesic effects of ethyl acetate fraction from chestnut (Castanea crenata var. dulcis) inner skin on Aβ(25-35)-induced cognitive deficits in mice

To investigate neuronal cell protective effects of an ethyl acetate fraction from chestnut inner skin, in vitro assays, including 2',7'-dichlorofluorescein diacetate, 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT), and lactate dehydrogenase (LDH), were performed. Intracellular accumulation of reactive oxygen species resulting from hydrogen peroxide (H(2)O(2)) treatment of PC12 cells was significantly reduced when ethyl acetate fractions were present in the medium compared to PC12 cells treated with H(2)O(2) only. In a cell viability assay using MTT, the ethyl acetate fraction protected against H(2)O(2)-induced neurotoxicity, and inhibited LDH release into the medium. In addition, the ethyl acetate fraction improved in vivo cognitive ability against amyloid β-peptide (Aβ)-induced neuronal deficit. High-performance liquid chromatography analyses showed that gallic acid, catechin, and epicatechin were predominant phenolics in the ethyl acetate fraction. Consequently, the results suggest that chestnut inner skin, including above phenolics, could ameliorate Aβ-induced learning and memory deficiency, and be utilized as effective substances for neurodegenerative disorders, notably Alzheimer's disease.

Nutrition-based health: cell-based bioassays for food antioxidant activity evaluation

Food science has progressively evolved and now there are wide evidences that foods have biological activities that are beyond their classical nutritional value. In this field, the antioxidant activity of pure compounds, food, feed, and dietary supplements has been extensively studied and numerous analytical approaches and assay models have been developed, involving various systems from simple chemical assays to animal models and human studies. This article is an overview of different cell-based models that have been used for testing the antioxidant properties of food, feed, and dietary supplements. Advantages, drawbacks, and technical problems to develop and validate suitable, robust, and high-throughput cell-based bioassays for screening food antioxidant activity will be discussed.

Protective effects of polyphenolic compounds on oxidative stress-induced cytotoxicity in PC12 cells

To investigate the beneficial properties associated with polyphenols, we screened 12 polyphenols for their ability to increase the viability of PC12 cells subjected to oxidative stress via CoCl2 and H2O2. Cell viability data demonstrate that 50 micromol/L methyl gallate and 50 micromol/L fisetin significantly increase viability of H2O2-stressed cells. Further, viability data suggest that 100 micromol/L epigallocatechin gallate (EGCG) increases basal viability, but has no rescue effect on cells stressed with CoCl2 or H2O2. Analysis of intracellular reactive oxygen species (ROS) shows that EGCG, methyl gallate, and gallic acid are effective in reducing CoCl2-derived ROS, and that methyl gallate is effective in attenuating H2O2-derived ROS. Examination of nitric oxide concentrations shows that methyl gallate significantly increases nitric oxide, both in nonstressed and H2O2-stressed cells, whereas EGCG results are consistent with the scavenging of nitric oxide under nonstressed and stressed conditions. Furthermore, analysis of total glutathione levels reveals that EGCG, methyl gallate, and gallic acid pretreatments with and without H2O2 stress have the ability to significantly alter glutathione metabolism. These findings suggest that EGCG, methyl gallate, and gallic acid may have potential therapeutic properties.

Chemical composition and physicochemical properties of green banana (Musa acuminata x balbisiana Colla cv. Awak) flour

Flour was prepared from peeled and unpeeled banana Awak ABB. Samples prepared were subjected to analysis for determination of chemical composition, mineral, dietary fibre, starch and total phenolics content, antioxidant activity and pasting properties. In general, flour prepared from unpeeled banana was found to show enhanced nutrition values with higher contents of mineral, dietary fibre and total phenolics. Hence, flour fortified with peel showed relatively higher antioxidant activity. On the other hand, better pasting properties were shown when banana flour was blended with peel. It was found that a relatively lower pasting temperature, peak viscosity, breakdown, final viscosity and setback were evident in a sample blended with peel.

Biotransformed blueberry juice protects neurons from hydrogen peroxide-induced oxidative stress and mitogen-activated protein kinase pathway alterations

A growing body of evidence supports the therapeutic effects of blueberry in neurodegenerative disorders. Biotransformation of blueberry juice by Serratia vaccinii bacteria increases its phenolic content and antioxidant activity. In neuronal cell culture, biotransformed blueberry juice (BJ) significantly increased the activity of antioxidant enzymes, namely catalase and superoxide dismutase. Moreover, BJ protected neurons against H2O2-induced cell death in a dose-dependent manner. This associated with the upregulation of mitogen-activated protein kinase (MAPK) family enzymes p38 and c-Jun N-terminal kinase (JNK) activation, as well as with the protection of extracellular signal-regulated kinase (ERK1/2) and MAPK/ERK kinase (MEK1/2) activity loss induced by H2O2. The present studies demonstrate that BJ can protect neurons against oxidative stress possibly by increasing antioxidant enzyme activities and activating p38- and JNK-dependent survival pathways while blocking MEK1/2- and ERK1/2-mediated cell death. Thus, BJ may represent a novel approach to prevent and to treat neurodegenerative disorders, and it may represent a source of novel therapeutic agents against these diseases.

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

Oxidative stress is implicated in several human illnesses, including neurological disorders such as Parkinson's and Alzheimer's diseases. Acai is largely consumed in Brazil and contains high levels of antioxidant compounds. This work aims to study the antioxidant activity of acai frozen fruit pulp in the cerebral cortex, hippocampus, and cerebellum of rats treated with the oxidizing agent hydrogen peroxide (H(2)O(2)). Pretreatment of tissue with acai decreased H(2)O(2)-induced damage of both lipids and proteins in all tissues tested. This fruit was also able to reduce the activities of the antioxidant enzymes superoxide dismutase and catalase to basal levels. We observed a negative correlation between the polyphenol content of acai and the levels of lipid (r = -0.689; P <or= .05) and protein damage (r = -0.569; P <or= .05), suggesting the participation of polyphenols in the observed antioxidant activity. These data suggest that acai has a positive contribution in the development of age-related neurodegenerative diseases.

Metabolic syndrome and the role of dietary lifestyles in Alzheimer's disease

Since Alzheimer's disease (AD) has no cure or preventive treatment, an urgent need exists to find a means of preventing, delaying the onset, or reversing the course of the disease. Clinical and epidemiological evidence suggests that lifestyle factors, especially nutrition, may be crucial in controlling AD. Unhealthy lifestyle choices lead to an increasing incidence of obesity, dyslipidemia and hypertension--components of the metabolic syndrome. These disorders can also be linked to AD. Recent research supports the hypothesis that calorie intake, among other non-genetic factors, can influence the risk of clinical dementia. In animal studies, high calorie intake in the form of saturated fat promoted AD-type amyloidosis, while calorie restriction via reduced carbohydrate intake prevented it. Pending further study, it is prudent to recommend to those at risk for AD--e.g. with a family history or features of metabolic syndrome, such as obesity, insulin insensitivity, etc.--to avoid foods and beverages with added sugars; to eat whole, unrefined foods with natural fats, especially fish, nuts and seeds, olives and olive oil; and to minimize foods that disrupt insulin and blood sugar balance.