Grape powder supplementation prevents oxidative stress-induced anxiety-like behavior, memory impairment, and high blood pressure in rats

A grape-supplemented diet prevented ultraviolet (UV) radiation-induced cataract by regulating Nrf2 and XIAP pathways

The purpose of this study is to investigate if grape consumption, in the form of grape powder (GP), could protect against ultraviolet (UV)-induced cataract. Mice were fed with the regular diet, sugar placebo diet, or a grape diet (regular diet supplemented with 5%, 10%, and 15% GP) for 3 months. The mice were then exposed to UV radiation to induce cataract. The results showed that the GP diet dose-dependently inhibited UV-induced cataract and preserved glutathione pools. Interestingly, UV-induced Nrf2 activation was abolished in the groups on the GP diet, suggesting GP consumption may improve redox homeostasis in the lens, making Nrf2 activation unnecessary. For molecular target prediction, a total of 471 proteins regulated by GP were identified using Agilent Literature Search (ALS) software. Among these targets, the X-linked inhibitor of apoptosis (XIAP) was correlated with all of the main active ingredients of GP, including resveratrol, catechin, quercetin, and anthocyanins. Our data confirmed that GP prevented UV-induced suppression of XIAP, indicating that XIAP might be one of the critical molecular targets of GP. In conclusion, this study demonstrated that GP protected the lens from UV-induced cataract development in mice. The protective effects of GP may be attributed to its ability to improve redox homeostasis and activate the XIAP-mediated antiapoptotic pathway.

Gallic acid ameliorates behavioral dysfunction, oxidative damage, and neuronal loss in the prefrontal cortex and hippocampus in stressed rats

Gallic acid (GA) is known to be a natural phenolic compound with antioxidant and neuroprotective effects. This study aims to investigate the impact of GA against restraint stress-induced oxidative damage, anxiety-like behavior, neuronal loss, and spatial learning and memory impairment in male Wistar rats. The animals were divided into four groups (n = 8) and subjected to restraint stress for 4 h per day for 14 consecutive days or left undisturbed (control without inducing stress). In the treatment group, the animals were treated with 2 mL normal saline plus 100 mg/kg GA per day for 14 consecutive days (STR + GA group). The animals received the drug or normal saline by gavage 2 h before inducing restraint stress. ELISA assay measured oxidative stress factors. Elevated-plus maze and Morris water maze tests assessed anxiety-like behavior and spatial learning and memory, respectively. Also, neuronal density was determined using Nissl staining. Restraint stress significantly increased MDA and reduced the activities of GPX and SOD in the stressed rats, which were reserved by treatment with 100 mg/kg GA. Restraint stress markedly enhanced the anxiety-like behavior and spatial learning and memory impairment that were reserved by GA. In addition, treatment with GA reduced the neuronal loss in the stressed rats in the hippocampus and prefrontal cortex (PFC) regions. Taken together, our findings suggest that GA has the potential to be used as a good candidate to attenuate neurobehavioral disorders as well as neuronal loss in the hippocampus and PFC induced by restraint stress via reducing oxidative damage.

Molecular Hydrogen: an Emerging Therapeutic Medical Gas for Brain Disorders

Oxidative stress and neuroinflammation are the main physiopathological changes involved in the initiation and progression of various neurodegenerative disorders or brain injuries. Since the landmark finding reported in 2007 found that hydrogen reduced the levels of peroxynitrite anions and hydroxyl free radicals in ischemic stroke, molecular hydrogen's antioxidative and anti-inflammatory effects have aroused widespread interest. Due to its excellent antioxidant and anti-inflammatory properties, hydrogen therapy via different routes of administration exhibits great therapeutic potential for a wide range of brain disorders, including Alzheimer's disease, neonatal hypoxic-ischemic encephalopathy, depression, anxiety, traumatic brain injury, ischemic stroke, Parkinson's disease, and multiple sclerosis. This paper reviews the routes for hydrogen administration, the effects of hydrogen on the previously mentioned brain disorders, and the primary mechanism underlying hydrogen's neuroprotection. Finally, we discuss hydrogen therapy's remaining issues and challenges in brain disorders. We conclude that understanding the exact molecular target, finding novel routes, and determining the optimal dosage for hydrogen administration is critical for future studies and applications.

The expanding impact of methylglyoxal on behavior-related disorders

Methylglyoxal (MGO) is a reactive dicarbonyl compound formed as a byproduct of glycolysis. MGO is a major cell-permeant precursor of advanced glycation end products (AGEs), since it readily reacts with basic phospholipids and nucleotides, as well as amino acid residues of proteins, such as arginine, cysteine, and lysine. The AGEs production induced by MGO are widely associated with several pathologies, including neurodegenerative diseases. However, the impact of MGO metabolism and AGEs formation in the central nervous system (particularly in neurons, astrocytes and oligodendrocytes) on behavior and psychiatric diseases is not fully understood. Here, we briefly present background information on the biological activity of MGO in the central nervous system. It was gathered the available information on the role of MGO metabolism at the physiological processes, as well as at the neurobiology of psychiatry diseases, especially pain-related experiences, anxiety, depression, and cognition impairment-associated diseases. To clarify the role of MGO on behavior and associated diseases, we reviewed primarily the main findings at preclinical studies focusing on genetic and pharmacological approaches. Since monoamine neurotransmitter systems are implicated as pivotal targets on the pathophysiology and treatment of psychiatry and cognitive-related diseases, we also reviewed how MGO affects these neurotransmission systems and the implications of this phenomenon for nociception and pain; learning and cognition; and mood. In summary, this review highlights the pivotal role of glyoxalase 1 (Glo1) and MGO levels in modulating behavioral phenotypes, as well as related cellular and molecular signaling. Conclusively, this review signals dopamine as a new neurochemical MGO target, as well as highlights how MGO metabolism can modulate the pathophysiology and treatment of pain, psychiatric and cognitive-related diseases.

Mulberry leaves juice attenuates arsenic-induced neurobehavioral and hepatic disorders in mice

Arsenic (As) poisoning has caused an environmental catastrophe in Bangladesh as millions of people are exposed to As-contaminated drinking water. Chronic As-exposure causes depression, memory impairment, and liver injury in experimental animals. This study was carried out to assess the protective effect of mulberry leaves juice (Mul) against As-induced neurobehavioral and hepatic dysfunctions in Swiss albino mice. As-exposed mice spent significantly reduced time in open arms and increased time spent in closed arms in the elevated plus maze (EPM) test, whereas they took significantly longer time to find the hidden platform in the Morris water maze (MWM) test and spent significantly less time in the desired quadrant when compared to the control mice. A significant reduction in serum BChE activity, an indicator of As-induced neurotoxicity-associated behavioral changes, was noted in As-exposed mice compared to control mice. Supplementation of Mul to As-exposed mice significantly increased serum BChE activity, increased the time spent in open arms and reduced time latency to find the hidden platform, and stayed more time in the target quadrant in EPM and MWM tests, respectively, compared to As-exposed-only mice. Also, a significantly reduced activity of BChE, AChE, SOD, and GSH in brain, and elevated ALP, AST, and ALT activities in serum were noted in As-exposed mice when compared to control mice. Mul supplementation significantly restored the activity of these enzymes and also recovered As-induced alterations in hepatic tissue in As-exposed mice. In conclusion, this study suggested that mulberry leaves juice attenuates As-induced neurobehavioral and hepatic dysfunction in mice.

Winery by-products as a valuable source for natural antihypertensive agents

Hypertension (HTN) is one of the leading causes of death in the world. Agri-food by-products are emerging as a novel source of natural antihypertensive agents allowing for their valorization and making food and agricultural industries more environmentally friendly. In this regard, wine making process generates large amounts of by-products rich in phenolic compounds that have shown potential to exert several beneficial effects including antihypertensive properties. The aim of this study was to review the blood pressure-lowering effects of winery by-products. In addition, molecular mechanisms involved in their bioactivity were also evaluated. Among the winery by-products, grape seed extracts have widely shown antihypertensive properties in both animal and human studies. Moreover, recent evidence suggests that grape stem, skin and pomace and wine lees may also have great potential to manage HTN, although more studies are needed in order to confirm their potential in humans. Improvement of endothelial dysfunction and reduction of oxidative stress associated with HTN are the main mechanisms involved in the blood pressure-lowering effects of these by-products.

Parental Lead Exposure Promotes Neurobehavioral Disorders and Hepatic Dysfunction in Mouse Offspring

Lead (Pb) induces neurotoxicity in both children and adults. Children are more vulnerable to Pb toxicity than adults. Little is known about the effects of Pb on the mental health of the children who are prenatally exposed. Therefore, we designed an animal experiment to compare the adverse effects of Pb on neurobehavioral and hepatic functions between Pb-exposed (Pb mice) and parental Pb-exposed (P-Pb mice) group mice. Mice were treated with Pb-acetate (10 mg/kg bodyweight/day) via drinking water. Male mice from unexposed parents treated with Pb for 90 days were defined as Pb mice, whereas male mice from Pb-exposed parents treated with Pb for further 90 days were defined as P-Pb mice. Anxiety-like behavior and spatial memory and learning were assessed by elevated plus maze and Morris water maze. Serum hepatic enzyme activities and butyrylcholinesterase activity were measured by an analyzer. P-Pb mice displayed increased anxiety-like behavior and memory and learning impairments compared to Pb mice. BChE activity was significantly decreased in P-Pb mice compared to Pb mice. Pb levels in the brains of P-Pb mice were significantly higher than those of Pb mice. The activities of serum hepatic enzymes of P-Pb mice were also higher than those of Pb mice. Additionally, histopathology data revealed that hepatic tissue injury was more pronounced in P-Pb mice than in Pb mice. Thus, the results suggest that persistent exposure to Pb from fetus to adult causes more severe neurobehavioral changes and hepatic toxicities than adult exposure only.

Effect of Dietary Grapes on Female C57BL6/J Mice Consuming a High-Fat Diet: Behavioral and Genetic Changes

(1) Background: Adverse effects of a chronic high-fat diet (HFD) on murine behavior, cognition, and memory are well established. Polyphenols such as resveratrol, anthocyanins, and flavonoids, that are known for antioxidative and anti-inflammatory properties, are present in grapes. The objective of this work was to determine if the dietary intake of grapes has the potential of alleviating HFD-induced deficiencies. (2) Methods: The effect of dietary grape intake was studied using behavioral assays and high throughput genome-wide RNA transcriptome analyses with female C57BL6/J mice. (3) Results: Mice that were fed a HFD from 3-weeks of age showed anxiety-like behaviors compared with the standard diet (STD). This HFD-induced effect was attenuated by supplementing the HFD with 1% grape powder (HF1G) (open field test). Similar results were observed with the novel object recognition test; there was a significant difference in time spent exploring a novel object between the HFD and the HF1G groups. There was no significant difference between the HFD1G and the STD groups. Based on the RNA-Seq analysis, genetic expression in the brain varied as a result of diet, with 210, 360, and 221 uniquely expressed genes in the STD, HFD, and HF1G groups, respectively. Cluster analysis revealed that the HFIG group mapped more closely with the STD group than the HFD group. Focusing on some specific areas, based on genetic expression, Dopamine receptor 2 (Drd2) was increased in the HFD group and normalized in the HF1G group, relative to the STD group. In addition, as judged by cluster hierarchy, the expression of genes that are associated with the dopamine receptor 2 pathway were increased in the HFD group, whereas the pattern that was derived from mouse brain from the HF1G group showed greater similarity to the STD group. KEGG pathway analyses were consistent with these results. For example, neuroactive ligand-receptor interaction (KEGG ID: mmu04080) was altered due to HFD compared with STD, but normalized by grape supplementation or the HFD; there was no significant difference between the STD and HF1G groups. In addition, the expression of genes related to feeding behavior, such as Adora2a, Th, and Trh, were also increased in the HFD group compared with the STD group, and attenuated by grape supplementation. (4) Conclusions: Dietary grape consumption has positive effects on behavior and cognition that are impaired by a HFD. Attenuation of these effects correlates with global transcriptional changes in mouse brain.

Effects of Polyphenols on Oxidative Stress, Inflammation, and Interconnected Pathways during Spinal Cord Injury

Despite the progression in targeting the complex pathophysiological mechanisms of neurodegenerative diseases (NDDs) and spinal cord injury (SCI), there is a lack of effective treatments. Moreover, conventional therapies suffer from associated side effects and low efficacy, raising the need for finding potential alternative therapies. In this regard, a comprehensive review was done regarding revealing the main neurological dysregulated pathways and providing alternative therapeutic agents following SCI. From the mechanistic point, oxidative stress and inflammatory pathways are major upstream orchestras of cross-linked dysregulated pathways (e.g., apoptosis, autophagy, and extrinsic mechanisms) following SCI. It urges the need for developing multitarget therapies against SCI complications. Polyphenols, as plant-derived secondary metabolites, have the potential of being introduced as alternative therapeutic agents to pave the way for treating SCI. Such secondary metabolites presented modulatory effects on neuronal oxidative stress, neuroinflammatory, and extrinsic axonal dysregulated pathways in the onset and progression of SCI. In the present review, the potential role of phenolic compounds as critical phytochemicals has also been revealed in regulating upstream dysregulated oxidative stress/inflammatory signaling mediators and extrinsic mechanisms of axonal regeneration after SCI in preclinical and clinical studies. Additionally, the coadministration of polyphenols and stem cells has shown a promising strategy for improving post-SCI complications.

Mental Health in New Mothers: A Randomised Controlled Study into the Effects of Dietary Flavonoids on Mood and Perceived Quality of Life

The postnatal period is a significant period of physical, physiological and psychological change for mothers, rendering them particularly vulnerable to changes in mood or disorders such as postnatal depression (PND). Previous interventions with foods high in flavonoids have demonstrated beneficial acute and chronic mood effects in healthy child, adolescent and adult populations. It is unclear whether mood effects persist in populations who are potentially at-risk of developing mood disorders, such as postnatal mothers. This exploratory study investigated the effects of a 2-week daily dietary flavonoid intervention on mood (PANAS-NOW), anxiety (STAI), depressive symptoms (PHQ-8) and perceived quality of life (WHOQOL-BREF) in forty-one new mothers in the 0–12-month postnatal period, before and after flavonoid intervention. Mothers either added high flavonoid foods to their daily diet, or did not include additions following a randomised, between-groups, controlled design. Significant effects were observed in the flavonoid group with mothers reporting lower state anxiety and higher perceived quality of physical health at the 2-week timepoint. These findings suggest that regular dietary consumption of flavonoids may benefit mothers’ anxiety and perceived quality of life in the postnatal period. Replication of these results may indicate the potential for dietary flavonoids to promote healthy mood regulation in mothers or prevent the onset or severity of symptoms in postnatal psychological disorders, both of which would be beneficial for women’s health services and public mental health.

The role of biofactors in the prevention and treatment of age-related diseases

The present demographic changes toward an aging society caused a rise in the number of senior citizens and the incidence and burden of age-related diseases (such as cardiovascular diseases [CVD], cancer, nonalcoholic fatty liver disease [NAFLD], diabetes mellitus, and dementia), of which nearly half is attributable to the population ≥60 years of age. Deficiencies in individual nutrients have been associated with increased risks for age-related diseases and high intakes and/or blood concentrations with risk reduction. Nutrition in general and the dietary intake of essential and nonessential biofactors is a major determinant of human health, the risk to develop age-related diseases, and ultimately of mortality in the older population. These biofactors can be a cost-effective strategy to prevent or, in some cases, even treat age-related diseases. Examples reviewed herein include omega-3 fatty acids and dietary fiber for the prevention of CVD, α-tocopherol (vitamin E) for the treatment of biopsy-proven nonalcoholic steatohepatitis, vitamin D for the prevention of neurodegenerative diseases, thiamine and α-lipoic acid for the treatment of diabetic neuropathy, and the role of folate in cancer epigenetics. This list of potentially helpful biofactors in the prevention and treatment of age-related diseases, however, is not exhaustive and many more examples exist. Furthermore, since there is currently no generally accepted definition of the term biofactors, we here propose a definition that, when adopted by scientists, will enable a harmonization and consistent use of the term in the scientific literature.

In vivo evaluation of arsenic-associated behavioral and biochemical alterations in F0 and F1 mice

Groundwater contaminated with arsenic (As) is the biggest threat to public health in Bangladesh. The children of As-exposure parents are also exposing to As through drinking water. The effects of As on the children's health of As-exposure parents are poorly understood. An animal study was taken to evaluate the effects of As on behavioral and biochemical changes in F₁ mice. Swiss albino mice were separated into three groups: a) control, b) As-treated F₀ and c) As-treated F₁. Elevated plus maze and Morris water maze tests were used for evaluating anxiety, spatial memory and learning, respectively. We found that the effect of As on anxiety like behavior, spatial memory and learning impairment in As-treated F₁ mice was significantly higher than that of As-treated F₀ mice and control group. Additionally, we also evaluated the effects of As on biochemical parameters by measuring ALT, AST, ALP, BChE, SOD activities and the level of creatinine in As-induced mice, where we found that all of the blood parameters were significantly changed in F₁ generation. A significant portion of As accumulated in the brain, liver and kidney of F₁ mice than F₀ mice. Histological analysis revealed a significant change in tissue damage related to hepatic and renal dysfunctions that might be associated with As-induced biochemical alterations. In conclusion, arsenic plays an important role for the development of As-associated neurological disorders, hepatic toxicities, and renal dysfunctions in both F₀ and F₁ generations. Notably F₁ mice were much more vulnerable to As-exposure than F₀ mice.

Involvement of oxidative stress and mitochondrial mechanisms in air pollution-related neurobiological impairments

Background

Vehicle exhaust emissions are known to be significant contributors to physical and psychological stress. Vehicle exhaust-induced stress and associated respiratory and cardiovascular complications are well-known, but the impact of this stress on the brain is unclear. Simulated vehicle exhaust exposure (SVEE) in rats causes behavioral and cognitive deficits. In the present study, the underlying mechanisms were examined. Our postulation is that SVEE, a simulation of physiologically relevant concentrations of pro-oxidants (0.04% carbon dioxide, 0.9 ppm nitrogen dioxide, 3 ppm carbon monoxide) creates a toxic stress environment in the brain that results in an imbalance between production of reactive oxygen species and the counteracting antioxidant mechanisms. This impairs mitochondrial function in the high bioenergetic demand areas of the brain including the hippocampus (HIP), amygdala (AMY) and the prefrontal cortex (PFC), disrupting neuronal network, and causing behavioral deficits. Mitochondria-targeted antioxidant Mito-Q protects against these impairments.

Methods

Sprague Dawley rats were provided with Mito-Q (250 μM) in drinking water for 4 weeks followed by SVEE 5 h/day for 2 weeks, followed by behavioral and biochemical assessments.

Results

SVEE resulted in anxiety- and depression-like behavior, accompanied with increased oxidative stress, diminished antioxidant response and mitochondrial impairment reflected from electron transport chain (ETC) disruption, reduced oxygen consumption, low adenosine tri-phosphate (ATP) synthesis and an alteration in the mitochondrial biochemical dynamics assessed via protein expression profiles of mitochondrial fission marker, dynamin-related protein-1 and fusion markers, mitofusin-1/2 in the HIP, AMY and the PFC. Mito-Q treatment prevented SVEE-induced behavioral deficits, attenuated rise in oxidative stress and also prevented SVEE-induced mitochondrial impairment.

Conclusion

This study demonstrates a causal mechanism mediating SVEE-induced behavioral deficits in rats. We further established that SVEE is a toxicological stressor that induces oxidative stress and results in mitochondrial impairment, which by disrupting neural circuitry impairs cognitive and behavioral functions.

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Simulated vehicle exhaust exposure is a source of toxicological stress.

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Prolonged exposure leads to behavioral deficits and elevated oxidative stress.

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Oxidative stress elevation triggers mitochondrial impairment in the brain.

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Mito-Q prevents exhaust-associated behavioral and biochemical alterations.

The Gut Microbiota Links Dietary Polyphenols With Management of Psychiatric Mood Disorders

The pathophysiology of depression is multifactorial yet generally aggravated by stress and its associated physiological consequences. To effectively treat these diverse risk factors, a broad acting strategy is required and is has been suggested that gut-brain-axis signaling may play a pinnacle role in promoting resilience to several of these stress-induced changes including pathogenic load, inflammation, HPA-axis activation, oxidative stress and neurotransmitter imbalances. The gut microbiota also manages the bioaccessibility of phenolic metabolites from dietary polyphenols whose multiple beneficial properties have known therapeutic efficacy against depression. Although several potential therapeutic mechanisms of dietary polyphenols toward establishing cognitive resilience to neuropsychiatric disorders have been established, only a handful of studies have systematically identified how the interaction of the gut microbiota with dietary polyphenols can synergistically alleviate the biological signatures of depression. The current review investigates several of these potential mechanisms and how synbiotics, that combine probiotics with dietary polyphenols, may provide a novel therapeutic strategy for depression. In particular, synbiotics have the potential to alleviate neuroinflammation by modulating microglial and inflammasome activation, reduce oxidative stress and balance serotonin metabolism therefore simultaneously targeting several of the major pathological risk factors of depression. Overall, synbiotics may act as a novel therapeutic paradigm for neuropsychiatric disorders and further understanding the fundamental mechanisms of gut-brain-axis signaling will allow full utilization of the gut microbiota's as a therapeutic tool.

The possible neuroprotective role of grape seed extract on the histopathological changes of the cerebellar cortex of rats prenatally exposed to Valproic Acid: animal model of autism

Autism Spectrum Disorder (ASD) is a heterogeneous neurodevelopmental disease characterized by defect in verbal and nonverbal communications. As, the cerebellum has the greatest number of neurons and synapses in the central nervous system so, the cerebellum has emerged as one of the target brain areas affected in autism. The aim of this work was to study the biochemical, immunohistochemical and ultrastructural characteristics of autism and the possible neuroprotective role of grape seed extract. In this study 28 male pups were divided into Control groups; Group I (saline), Group II (GSE 400 mg/kg), Group III (VPA 500 mg/kg) and Group IV (VPA and GSE). Cerebellar hemispheres were dissected out and prepared to determine the oxidative stress markers, histological, immunohistochemical and morphometric study were done. A significant elevation in oxidative stress markers in off spring of VPA treated rats in comparison to control group was detected. A significant decrease in the Purkinje cell count and nuclear size were observed. Numerous shrunken cells with hyperchromatic nuclei and ultrastructural degeneration of cytoplasmic organelles were detected. A significant rise in the area percentage of GFAP-positive immune stained cells in comparison to that of the control groups was seen. Strikingly, GSE revealed significant improvement in the oxidative stress markers and then the histological and morphometric picture of the cerebellum. GSE has neuroprotective effect on the cerebellum of VPA treated rats through its potent antioxidant effect.

Protective Effects of Foods Containing Flavonoids on Age-Related Cognitive Decline

PURPOSE OF REVIEW

Evidence suggests that flavonoids, polyphenolic compounds found in many plant-derived foods, such as berries, may allay cognitive impairment. We review recent research exploring the protective effects of flavonoids on age-related cognitive decline and neurodegenerative disorders in humans and animals. We also address the mechanisms by which flavonoids may exert their effects and promising avenues of future research.

RECENT FINDINGS

Flavonoids have been found to decrease neuroinflammation, reduce oxidative stress, and mediate neuroplasticity in animal models of neurodegeneration and aging. Injecting flavonoids encased in metal nanoparticles may further enhance the efficacy of flavonoids. Animal studies also demonstrate that flavonoid supplementation may alleviate neurodegenerative cognitive and memory impairments. Limited human studies, however, demonstrate the need for further clinical research investigating flavonoids. Flavonoid supplementation, as well as dietary modification to include whole foods high in flavonoids, may provide therapeutic potential for aging individuals experiencing cognitive deficits resulting from neurodegeneration.

Withania somnifera root powder protects againist post-traumatic stress disorder-induced memory impairment

Post-traumatic stress disorder (PTSD) is precipitated by exposure to severe traumatic events such as wars, natural disasters, catastrophes, or other traumatic events. Withania somnifera (WS) Dunal (family: Solanaceae) known traditionally as "Ashwaghanda" is used widely in ayurvedic medicine, and known to have positive role in neurodegenerative diseases. In this study, WS effect on impairment of memory due to PTSD was studied in animal models. Single-prolonged stress rat model, which consisted of restrain for 2 h, forced swimming for 20 min, rest for 15 min, and diethyl ether exposure for 1-2 min, was used to induce PTSD animals. The WS root powder extract was administered orally at a dose of 500 mg/kg/day. The radial arm water maze (RAWM) was used to assess spatial learning and memory. Enzymatic assays were used to evaluate changes in oxidative stress biomarkers in the hippocampus following treatments. The result showed that PTSD resulted in short- and long- term memory impairments. Administration of WS prevented this impairment of memory induced by PTSD. Furthermore, WS prevented PTSD induced changes in oxidative stress biomarker in the hippocampus. For quality assessment, the methanolic extract for WS was subjected to UHPLC analysis. A calibration curve for isowithanone as a marker compound was constructed. WS roots content of isowithanone was found to be 0.23% (w/w). In conclusion, WS administration prevented PTSD induced memory impairment probably through preserving changes in antioxidant mechanisms in the hippocampus.

Comparative Evaluation of Conventional and Novel Extracts of Stem Bark of Terminalia arjuna for Antihypertensive Activity in BSO Induced Oxidative Stress based Rat Model

BACKGROUND

Terminalia arjuna (TA) has been reported and explored traditionally for its cardiotonic properties while the mechanism of antihypertensive effect of TA has not been clearly reported.

METHOD

The oxidative stress is a major cause for hypertension, hence different extracts of TA having variable marker yield were evaluated for their antihypertensive effect in buthionine sulfoxamine (BSO) induced oxidative stress based model. Soxhlet extraction (SE), room temperature extraction (RTE), microwave assisted extraction (MAE), and ultrasound assisted extraction (USAE) were quantitatively estimated for marker compounds arjunolic acid and arjunic acid through HPTLC.

RESULTS

The hypertension was induced using buthionine sulfoxamine (2 mmol/kg b.w. i.p.) and results suggested that the MAE and USAE showed better recovery of systolic blood pressure (110.33±0.10 and 118.33±0.10) and GSH level (3.62±0.07 nmoles/mL and 3.22±0.13 nmoles/mL), respectively as compared to the positive control group treated with ascorbic acid (Systolic BP: 119.67±0.10, GSH level: 3.11±0.10 nmoles/mL). The RTE and SE also showed a decrease in hypertension but were having moderate effect as compared with the standard positive control.

CONCLUSION

The total percentage yield, the yield of the marker compounds arjunolic and arjunic acid, the IC50 values for antioxidant activity as well as the antihypertensive effect were in order: MAE>USAE>SE>RTE that suggested the role of biomarkers arjunolic acid and arjunic acid in reversing the effect of buthionine sulfoxamine.

Cellular Redox Imbalance and Neurochemical Effect in Cognitive-Deficient Old Rats

The purpose of the present study is to access the linkage between dysregulation of glutamatergic neurotransmission, oxidative metabolism, and serine signaling in age-related cognitive decline. In this work, we evaluated the effect of natural aging in rats on the cognitive abilities for hippocampal-dependent tasks. Oxidative metabolism indicators are glutathione (GSH), malondialdehyde (MDA) concentrations, and cytosolic phospholipase A₂ (PLA₂) activity. In addition, neurotransmitter amino acid (L-Glutamic acid, γ-aminobutyric acid (GABA), DL-Serine and DL-Aspartic acid) concentrations were studied in brain areas such as the frontal cortex (FC) and hippocampus (HPC). The spatial long-term memory revealed significant differences among experimental groups: the aged rats showed an increase in escape latency to the platform associated with a reduction of crossings and spent less time on the target quadrant than young rats. Glutathione levels decreased for analyzed brain areas linked with a significant increase in MDA concentrations and PLA₂ activity in cognitive-deficient old rats. We found glutamate levels only increased in the HPC, whereas a reduced level of serine was found in both regions of interest in cognitive-deficient old rats. We demonstrated that age-related changes in redox metabolism contributed with alterations in synaptic signaling and cognitive impairment.

Neuroprotection through flavonoid: Enhancement of the glyoxalase pathway

The glyoxalase pathway functions to detoxify reactive dicarbonyl compounds, most importantly methylglyoxal. The glyoxalase pathway is an antioxidant defense mechanism that is essential for neuroprotection. Excessive concentrations of methylglyoxal have deleterious effects on cells, leading to increased levels of inflammation and oxidative stress. Neurodegenerative diseases - including Alzheimer's, Parkinson's, Aging and Autism Spectrum Disorder - are often induced or exacerbated by accumulation of methylglyoxal. Antioxidant compounds possess several distinct mechanisms that enhance the glyoxalase pathway and function as neuroprotectants. Flavonoids are well-researched secondary plant metabolites that appear to be effective in reducing levels of oxidative stress and inflammation in neural cells. Novel flavonoids could be designed, synthesized and tested to protect against neurodegenerative diseases through regulating the glyoxalase pathway.

Botanicals as Modulators of Neuroplasticity: Focus on BDNF

The involvement of brain-derived neurotrophic factor (BDNF) in different central nervous system (CNS) diseases suggests that this neurotrophin may represent an interesting and reliable therapeutic target. Accordingly, the search for new compounds, also from natural sources, able to modulate BDNF has been increasingly explored. The present review considers the literature on the effects of botanicals on BDNF. Botanicals considered were Bacopa monnieri (L.) Pennell, Coffea arabica L., Crocus sativus L., Eleutherococcus senticosus Maxim., Camellia sinensis (L.) Kuntze (green tea), Ginkgo biloba L., Hypericum perforatum L., Olea europaea L. (olive oil), Panax ginseng C.A. Meyer, Rhodiola rosea L., Salvia miltiorrhiza Bunge, Vitis vinifera L., Withania somnifera (L.) Dunal, and Perilla frutescens (L.) Britton. The effect of the active principles responsible for the efficacy of the extracts is reviewed and discussed as well. The high number of articles published (more than one hundred manuscripts for 14 botanicals) supports the growing interest in the use of natural products as BDNF modulators. The studies reported strengthen the hypothesis that botanicals may be considered useful modulators of BDNF in CNS diseases, without high side effects. Further clinical studies are mandatory to confirm botanicals as preventive agents or as useful adjuvant to the pharmacological treatment.

A Randomized, Double-Blinded, Clinical Trial on Effects of a Vitis vinifera Extract on Cognitive Function in Healthy Older Adults

Introduction: Gradual population aging is creating a new set of needs in the general population. Memory capacity decreases with age, and memory deficits are considered an early symptom of Alzheimer’s Disease (AD), one of the most prevalent cognitive disorders in older people. Numerous studies have shown that grape polyphenolic compounds (GPs) are able to attenuate cognitive impairment and reduce brain lesions in experimental AD animal models. These GP effects are associated with improvement in brain antioxidant status and prevention of free radical-induced neuronal damage. We designed a randomized, double-blind, placebo-controlled clinical trial to investigate the potential beneficial effects of a Vitis vinifera-based dietary supplement on cognitive function and neuropsychological status in healthy older adults.

Methods: One-hundred eleven subjects were recruited and randomly divided in two groups: one group received the V. vinifera-based dietary supplement Cognigrape^® for 12 weeks (250 mg/day) and the second group received placebo over the same period of time. Before and after the end of the supplementation period, cognitive function and neuropsychological status were evaluated using the Mini-Mental State Examination (MMSE), Beck Depression Inventory (BDI), Hamilton Anxiety Rating Scale (HARS), and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) evaluations.

Results: MMSE scores were significantly improved after supplementation with Cognigrape^® in comparison with baseline levels (p < 0.0001) and placebo (r = 0.59, 0.95% CI 0.11, 1.22; p < 0.0001). Cognigrape^® supplementation produced a significant reduction in BDI (-15.8%) and HARS (-24.9%) scores with respect to baseline levels (p < 0.0001) and placebo (p < 0.0001 for BDI and p < 0.05 for HARS). RBANS total score was significantly improved by Cognigrape^® with respect to baseline levels and placebo (r = 0.55, 0.95% CI 0.48, 6.07; p < 0.0001). The comparison with the placebo revealed improvements in several parameters among participants receiving Cognigrape^®: attention (p < 0.001); language (p < 0.05); immediate memory (p < 0.0001); and delayed memory (p < 0.0001). Visuospatial/constructional abilities were not modified. During the study, no adverse effects were detected.

Conclusion: The results show that 12 weeks of Cognigrape^® supplementation is safe, can improve physiological cognitive profiles, and can concurrently ameliorate negative neuropsychological status in healthy older adults.

Psychological Impact of Vehicle Exhaust Exposure: Insights from an Animal Model

Air pollution resulting from exhaust emissions of vehicles has risen in the recent years, reportedly causing major adverse effects on the heart, lungs and the brain. Though respiratory and cardiovascular effects of these emissions are well identified, psychological and neurobiological complications of prolonged exposure to vehicle emissions remain unknown. Pro-oxidants are considered as major constituents of vehicle emissions. This is important considering causal link between oxidative stress and behavioral and cognitive impairments. We hypothesized that prolonged exposure to pro-oxidants in vehicle emissions result in behavioral and cognitive deficits. We developed a simulated vehicle exhaust exposure model in rats. The model used a simulated mixture of vehicle exhaust that comprised of pro-oxidant constituents of exhaust, namely, carbon dioxide (13%), carbon monoxide (0.68%) and nitrogen dioxide (1000 ppm) in air. Rats were exposed either to a high (1:10 dilution) or low (~1:1000 dilution) physiologically relevant dose of simulated mixture in air for two weeks in separate experiments followed by a comprehensive behavioral and cognitive analysis. We observed that prolonged exposure to pro-oxidants in vehicle exhaust increased anxiety-and depression-like behavior as well as led to impaired memory in rats. This is important preclinical evidence, particularly relevant to human population exposed to high vehicular traffic.

Modulating Oxidative Stress Relieves Stress-Induced Behavioral and Cognitive Impairments in Rats

Background

Persistent psychological stress often leads to anxiety disorders and depression. Benzodiazepines and selective serotonin reuptake inhibitors are popular treatment options but have limited efficacy, supporting the need for alternative treatment. Based on our recent preclinical work suggesting a causal link between neurobehavioral deficits and elevated oxidative stress, we hypothesized that interventions that mitigate oxidative stress can attenuate/overcome neurobehavioral deficits.

Methods

Here, we employed the rat social defeat model of psychological stress to determine whether increasing antioxidant levels using grape powder would prevent and/or reverse social defeat-induced behavioral and cognitive deficits. Furthermore, a hippocampal-derived HT22 cell culture model of oxidative stress was employed to identify the individual beneficial constituent(s) of grape powder and the underlying mechanism(s) of action.

Results

Grape powder treatment prevented and reversed social defeat-induced behavioral and cognitive deficits and also decreased social defeat-induced increase in plasma corticosterone and 8-isoprostane (systemic and oxidative stress markers, respectively). And grape powder treatment replenished social defeat-induced depleted pool of key antioxidant enzymes glyoxalase-1, glutathione reducatse-1, and superoxide dismutase. Grape powder constituents, quercetin and resveratrol, were most effective in preventing oxidative stress-induced decreased cellular antioxidant capacity. Grape powder protected oxidative stress-induced cell death by preventing calcium influx, mitochondrial dysfunction, and release of cytochrome c.

Conclusions

Grape powder treatment by increasing antioxidant pool and preventing cell damage and death prevented and reversed social defeat-induced behavioral and cognitive deficits in rats. Quercetin and resveratrol are the major contributors towards beneficial effects of grape powder.

Low maternal care is associated with increased oxidative stress in the brain of lactating rats

Maternal care is crucial for offspring development and licking/grooming patterns can be induced by sensorial, neuroendocrine, and metabolic variations in the CNS. Important brain functions, such as learning and memory, can be influenced by oxidative stress, which can also modulate pathophysiological processes (e.g., depression, anxiety, and other psychiatric disorders). This study evaluated oxidative stress in the hippocampus (HP), olfactory bulb (OB), and plasma in Low-Licking (LL) and High-Licking (HL) lactating rats through superoxide dismutase (SOD) and catalase (CAT) activities, DNA damage (comet assay), and dihydrodichlorofluorescein (DCF) oxidation assay. Results demonstrate that in the HP of LL, the activities of SOD and CAT were increased compared to HL. In the OB, the activities of SOD and CAT were also increased in LL. The comet assay in the HP showed that LL had higher levels of basal damage and increased levels of DNA breaks than HL. In the OB, LL also had higher levels of DNA damage. In the plasma, no difference was observed in either SOD or CAT activities, but the DCF oxidation assay revealed that LL had higher levels of ROS production than HL. In conclusion, we observed that LL mothers showed evidence of increased oxidative stress when compared to HL, suggesting that variations in maternal behavior might be related to these biochemical parameters.

Mitigating the effects of high fat diet on the brain and behavior with berry supplementation

Berries are rich in bioactive compounds like anthocyanins and show promise for mitigating the effects of high fat diet on the brain and behavior.

Grape Powder Improves Age-Related Decline in Mitochondrial and Kidney Functions in Fischer 344 Rats

We examined the effects and mechanism of grape powder- (GP-) mediated improvement, if any, on aging kidney function. Adult (3-month) and aged (21-month) Fischer 344 rats were treated without (controls) and with GP (1.5% in drinking water) and kidney parameters were measured. Control aged rats showed higher levels of proteinuria and urinary kidney injury molecule-1 (KIM-1), which decreased with GP treatment in these rats. Renal protein carbonyls (protein oxidation) and gp^91phox-NADPH oxidase levels were high in control aged rats, suggesting oxidative stress burden in these rats. GP treatment in aged rats restored these parameters to the levels of adult rats. Moreover, glomerular filtration rate and sodium excretion were low in control aged rats suggesting compromised kidney function, which improved with GP treatment in aged rats. Interestingly, low renal mitochondrial respiration and ATP levels in control aged rats were associated with reduced levels of mitochondrial biogenesis marker MtTFA. Also, Nrf2 proteins levels were reduced in control aged rats. GP treatment increased levels of MtTFA and Nrf2 in aged rats. These results suggest that GP by potentially regulating Nrf2 improves aging mitochondrial and kidney functions.

Age-dependent effects of esculetin on mood-related behavior and cognition from stressed mice are associated with restoring brain antioxidant status

Dietary antioxidants might exert an important role in the aging process by relieving oxidative damage, a likely cause of age-associated brain dysfunctions. This study aims to investigate the influence of esculetin (6,7-dihydroxycoumarin), a naturally occurring antioxidant in the diet, on mood-related behaviors and cognitive function and its relation with age and brain oxidative damage. Behavioral tests were employed in 11-, 17- and 22-month-old male C57BL/6J mice upon an oral 35day-esculetin treatment (25mg/kg). Activity of antioxidant enzymes, GSH and GSSG levels, GSH/GSSG ratio, and mitochondrial function were analyzed in brain cortex at the end of treatment in order to assess the oxidative status related to mouse behavior. Esculetin treatment attenuated the increased immobility time and enhanced the diminished climbing time in the forced swim task elicited by acute restraint stress (ARS) in the 11- and 17-month-old mice versus their counterpart controls. Furthermore, ARS caused an impairment of contextual memory in the step-through passive avoidance both in mature adult and aged mice which was partially reversed by esculetin only in the 11-month-old mice. Esculetin was effective to prevent the ARS-induced oxidative stress mostly in mature adult mice by restoring antioxidant enzyme activities, augmenting the GSH/GSSG ratio and increasing cytochrome c oxidase (COX) activity in cortex. Modulation of the mood-related behavior and cognitive function upon esculetin treatment in a mouse model of ARS depends on age and is partly due to the enhancement of redox status and levels of COX activity in cortex.

Gender Differences in the Neurobiology of Anxiety: Focus on Adult Hippocampal Neurogenesis

Although the literature reports a higher incidence of anxiety disorders in women, the majority of basic research has focused on male rodents, thus resulting in a lack of knowledge on the neurobiology of anxiety in females. Bridging this gap is crucial for the design of effective translational interventions in women. One of the key brain mechanisms likely to regulate anxious behavior is adult hippocampal neurogenesis (AHN). This review paper aims to discuss the evidence on the differences between male and female rodents with regard to anxiety-related behavior and physiology, with a special focus on AHN. The differences between male and female physiologies are greatly influenced by hormonal differences. Gonadal hormones and their fluctuations during the estrous cycle have often been identified as agents responsible for sexual dimorphism in behavior and AHN. During sexual maturity, hormone levels fluctuate cyclically in females more than in males, increasing the stress response and the susceptibility to anxiety. It is therefore of great importance that future research investigates anxiety and other neurophysiological aspects in the female model, so that results can be more accurately applicable to the female population.

Are Anxiety Disorders Associated with Accelerated Aging? A Focus on Neuroprogression

Anxiety disorders (AnxDs) are highly prevalent throughout the lifespan, with detrimental effects on daily-life functioning, somatic health, and quality of life. An emerging perspective suggested that AnxDs may be associated with accelerated aging. In this paper, we explored the association between AnxDs and hallmarks of accelerated aging, with a specific focus on neuroprogression. We reviewed animal and human findings that suggest an overlap between processes of impaired neurogenesis, neurodegeneration, structural, functional, molecular, and cellular modifications in AnxDs, and aging. Although this research is at an early stage, our review suggests a link between anxiety and accelerated aging across multiple processes involved in neuroprogression. Brain structural and functional changes that accompany normal aging were more pronounced in subjects with AnxDs than in coevals without AnxDs, including reduced grey matter density, white matter alterations, impaired functional connectivity of large-scale brain networks, and poorer cognitive performance. Similarly, molecular correlates of brain aging, including telomere shortening, Aβ accumulation, and immune-inflammatory and oxidative/nitrosative stress, were overrepresented in anxious subjects. No conclusions about causality or directionality between anxiety and accelerated aging can be drawn. Potential mechanisms of this association, limitations of the current research, and implications for treatments and future studies are discussed.

Tempol protects sleep-deprivation induced behavioral deficits in aggressive male Long-Evans rats

Earlier, we reported that elevated anxiety-like behavior and high aggression in aged retired breeder Long-Evans (L-E) rats was associated with increased plasma corticosterone and elevated oxidative stress levels. In the present study, we examined how this aged aggressive and anxious rat strain responds to acute sleep deprivation (24h) and whether their behaviors can be modulated via antioxidant tempol treatment. Four groups of L-E rats were utilized: naïve control (NC), tempol treated control (T+NC), sleep deprived (SD), tempol treated and sleep deprived (T+SD). Thus, two groups were treated with tempol (1mM in drinking water for 2 weeks) while the other two were not. Two groups were subjected to acute sleep deprivation (24h) using the columns-in-water model while the other two were not. Sleep deprivation induced anxiety-like behavior, led to significant depression-like behavior and short-term memory impairment in SD rats. And, decision-making behavior also was compromised in SD rats. These behavioral and cognitive impairments were prevented with tempol treatment in T+SD rats. Tempol treatment also reduced SD-induced increase in corticosterone and oxidative stress levels in T+SD rats. These results suggest potential involvement of oxidative stress mechanisms in regulation of sleep deprivation induced behavioral and cognitive deficits in male aged-aggressive rats.

Resveratrol, in its natural combination in whole grape, for health promotion and disease management

The grape antioxidant resveratrol has been a topic of intense research for the past three decades. Resveratrol and other grape ingredients, as well as whole-grape products, have shown considerable promise in health promotion and disease management. Phytochemically, whole grape represents a natural combination of resveratrol and other phytonutrients, as it contains several catechins, anthocyanins, polyphenols, and flavonols. Thus, whole grape products or specific combinations of grape constituents provide us with the possibility of synergistic interactions leading to improved efficacy. Recent research has suggested that whole-grape products may help in maintaining heart health and protect against aging, aging-associated diseases, neurodegeneration, and some cancers. On the basis of available recent literature, the grape fruit or whole-grape products seem to be safer choices for better health and disease prevention. However, for advanced disease conditions, individual grape ingredients (such as resveratrol) or combinations of multiple ingredients, together with existing therapies, appear to be better approaches. Further clinical studies are needed to understand the benefits of grapes and their products in the prevention and management of specific diseases.

Polyphenol Stilbenes: Molecular Mechanisms of Defence against Oxidative Stress and Aging-Related Diseases

Numerous studies have highlighted the key roles of oxidative stress and inflammation in aging-related diseases such as obesity, type 2 diabetes, age-related macular degeneration (AMD), and Alzheimer's disease (AD). In aging cells, the natural antioxidant capacity decreases and the overall efficiency of reparative systems against cell damage becomes impaired. There is convincing data that stilbene compounds, a diverse group of natural defence phenolics, abundant in grapes, berries, and conifer bark waste, may confer a protective effect against aging-related diseases. This review highlights recent data helping to clarify the molecular mechanisms involved in the stilbene-mediated protection against oxidative stress. The impact of stilbenes on the nuclear factor-erythroid-2-related factor-2 (Nrf2) mediated cellular defence against oxidative stress as well as the potential roles of SQSTM1/p62 protein in Nrf2/Keap1 signaling and autophagy will be summarized. The therapeutic potential of stilbene compounds against the most common aging-related diseases is discussed.

Grape powder treatment prevents anxiety-like behavior in a rat model of aging

Earlier, we have reported that grape powder (GP) treatment prevented pharmacologic and psychological stress-induced anxiety-like behavior and memory impairment in rats. Protective effects of GP were attributed to its antioxidant effects. In this study, we tested the hypothesis that age-associated behavioral and cognitive deficits such as anxiety and memory impairment will be ameliorated with GP treatment. Using a National Institute of Aging recommended rodent model of aging, we examined a potentially protective role of antioxidant-rich GP in age-associated anxiety-like behavior and memory impairment. Male Fischer 344 rats were randomly assigned into 4 groups: young rats (3 months old) provided with tap water or with 15 g/L GP dissolved in tap water for 3 weeks, aged rats (21 months old) provided with tap water or with GP-treated tap water for 3 weeks (AG-GP). Anxiety-like behavior was significantly greater in aged rats compared with young rats, GP-treated young rats, or aged control rats (P < .05). Also, GP treatment prevented age-induced anxiety-like behavior in AG-GP rats (P < .05). Neither short-term nor long-term age-associated memory deficits improved with GP treatment in AG-GP rats. Furthermore, aged rats showed increased level of physiological stress (corticosterone) and increased oxidative stress in the plasma (8-isoprostane) as well as in selected brain areas (protein carbonylation). Grape powder treatment prevented age-induced increase in corticosterone levels and plasma 8-isoprostane levels in aged rats (P < .05), whereas protein carbonylation was recovered in the amygdala region only (P < .05). Grape powder by regulating oxidative stress ameliorates age-induced anxiety-like behavior in rats, whereas age-associated memory deficits seem unaffected with GP treatment.

Tempol treatment reduces anxiety-like behaviors induced by multiple anxiogenic drugs in rats

We have published that pharmacological induction of oxidative stress (OS) causes anxiety-like behavior in rats. Using animal models, we also have established that psychological stress induces OS and leads to anxiety-like behaviors. All evidence points towards the causal role of OS in anxiety-like behaviors. To fully ascertain the role of OS in anxiety-like behaviors, it is reasonable to test whether the pro-anxiety effects of anxiogenic drugs caffeine or N-methyl-beta-carboline-3-carboxamide (FG-7142) can be mitigated using agents that minimize OS. In this study, osmotic pumps were either filled with antioxidant tempol or saline. The pumps were attached to the catheter leading to the brain cannula and inserted into the subcutaneous pocket in the back pocket of the rat. Continuous i.c.v. infusion of saline or tempol in the lateral ventricle of the brain (4.3 mmol/day) was maintained for 1 week. Rats were intraperitoneally injected either with saline or an anxiogenic drug one at a time. Two hours later all groups were subjected to behavioral assessments. Anxiety-like behavior tests (open-field, light-dark and elevated plus maze) suggested that tempol prevented anxiogenic drug-induced anxiety-like behavior in rats. Furthermore, anxiogenic drug-induced increase in stress examined via plasma corticosterone and increased oxidative stress levels assessed via plasma 8-isoprostane were prevented with tempol treatment. Protein carbonylation assay also suggested preventive effect of tempol in the prefrontal cortex brain region of rats. Antioxidant protein expression and pro-inflammatory cytokine levels indicate compromised antioxidant defense as well as an imbalance of inflammatory response.

Adaptive cellular stress pathways as therapeutic targets of dietary phytochemicals: focus on the nervous system

During the past 5 decades, it has been widely promulgated that the chemicals in plants that are good for health act as direct scavengers of free radicals. Here we review evidence that favors a different hypothesis for the health benefits of plant consumption, namely, that some phytochemicals exert disease-preventive and therapeutic actions by engaging one or more adaptive cellular response pathways in cells. The evolutionary basis for the latter mechanism is grounded in the fact that plants produce natural antifeedant/noxious chemicals that discourage insects and other organisms from eating them. However, in the amounts typically consumed by humans, the phytochemicals activate one or more conserved adaptive cellular stress response pathways and thereby enhance the ability of cells to resist injury and disease. Examplesof such pathways include those involving the transcription factors nuclear factor erythroid 2-related factor 2, nuclear factor-κB, hypoxia-inducible factor 1α, peroxisome proliferator-activated receptor γ, and forkhead box subgroup O, as well as the production and action of trophic factors and hormones. Translational research to develop interventions that target these pathways may lead to new classes of therapeutic agents that act by stimulating adaptive stress response pathways to bolster endogenous defenses against tissue injury and disease. Because neurons are particularly sensitive to potentially noxious phytochemicals, we focus on the nervous system but also include findings from other cell types in which actions of phytochemicals on specific signal transduction pathways have been more thoroughly studied.

Plant-derived flavanol (-)epicatechin mitigates anxiety in association with elevated hippocampal monoamine and BDNF levels, but does not influence pattern separation in mice

Flavanols found in natural products such as cocoa and green tea elicit structural and biochemical changes in the hippocampus, a brain area important for mood and cognition. Here, we evaluated the outcome of daily consumption of the flavanol (-)epicatechin (4 mg per day in water) by adult male C57BL/6 mice on measures of anxiety in the elevated plus maze (EPM) and open field (OF). Furthermore, pattern separation, the ability to distinguish between closely spaced identical stimuli, considered to be mediated by the hippocampal dentate gyrus (DG), was tested using the touchscreen. To investigate mechanisms through which (-)epicatechin may exert its effects, mice were injected with bromodeoxyuridine (50 mg kg(-1)) to evaluate adult hippocampal neurogenesis. In addition, monoaminergic and neurotrophin signaling pathway proteins were measured in tissue derived from subject cortices and hippocampi. Flavanol consumption reduced anxiety in the OF and EPM. Elevated hippocampal and cortical tyrosine hydroxylase, downregulated cortical monoamine oxidase-A levels, as well as increased hippocampal brain-derived neurotrophic factor (BDNF) and pro-BDNF support the flavanol's anxiolytic effects. In addition, elevated pAkt in hippocampus and cortex was observed. (-)Epicatechin ingestion did not facilitate touchscreen performance or DG neurogenesis, suggesting a non-neurogenic mechanism. The concurrent modulation of complementary neurotrophic and monoaminergic signaling pathways may contribute to beneficial mood-modulating effects of this flavanol.

Grape powder prevents cognitive, behavioral, and biochemical impairments in a rat model of posttraumatic stress disorder

Previously, using the single-prolonged stress (SPS) rat model of posttraumatic stress disorder, we reported that moderate treadmill exercise, via modulation of oxidative stress-related mechanisms, rescued anxiety- and depression-like behaviors and reversed SPS-induced memory impairment. In this study using the SPS model (2-hour restrain, 20-minute forced swimming, 15-minute rest, and 1-2-minute diethyl ether exposure), we hypothesized that antioxidant rich grape powder (GP) prevents SPS-induced behavioral and memory impairment in rats. Male Sprague Dawley rats were randomly assigned into control (CON) (provided tap water), SPS (provided tap water), GP-SPS (provided 15 g/L GP in tap water for 3 weeks followed by SPS), or GP-CON (3 weeks of GP followed by CON exposure). Anxiety- and depression-like behaviors were significantly greater in SPS rats, when compared with CON- or GP-treated rats, and GP reversed these behavioral deficits. Single-prolonged stress rats made significantly more errors in both short- and long-term memory tests compared with CON- or GP-treated rats, which were prevented in GP-SPS rats. Grape powder prevented SPS-induced increase in plasma corticosterone level. Furthermore, brain-derived neurotrophic factor levels were significantly decreased in amygdala of SPS rats but not in GP-SPS rats compared with CON or (GP-CON) rats. In addition, GP significantly increased acetylated histone 3 and histone deacetylase 5 in hippocampus and amygdala of SPS rats as compared with CON or GP-CON rats. In conclusion, we suggest protective role of GP in SPS-induced behavioral, cognitive, and biochemical impairments in rats. Perhaps, epigenetic regulation of brain-derived neurotrophic factor enables GP-mediated prevention of SPS-induced deficits in rats.

High aggression in rats is associated with elevated stress, anxiety-like behavior, and altered catecholamine content in the brain

The social defeat paradigm involves aggressive encounters between Long-Evans (L-E) (resident) and Sprague-Dawley (S-D) (intruder) rats. Successful application of chronic social defeat stress in S-D rats is dependent upon selection of highly aggressive L-E rats. Half of the L-E rats screened for aggression did not meet the criterion for aggression (L-E rats performing a defeat, characterized by the intruder surrendering or acquiring a supine position for at least 3s). The observation of the differences in the level of aggression between age and weight matched L-E rats was quite compelling which led us to the present study. Herein, we measured behavioral differences between aggressor and non-aggressor L-E rats. We analyzed their anxiety-like behavior using open-field and elevated plus maze tests. We also measured aggression/violence-like behavior using two tests. In one, time taken to defeat the intruder S-D rat was recorded. In the second test, time taken to attack a novel object was compared between the two groups. We observed a significant increase in anxiety-like behavior in aggressor rats when compared to the non-aggressive group. Furthermore, time taken to defeat the intruder rat and to attack a novel object was significantly lower in aggressive L-E rats. Biochemical data suggests that heightened anxiety-like behavior and aggression is associated with increased plasma levels of corticosterones and elevated oxidative stress. Significant alterations in dopamine (DA), norepinephrine (NE) and epinephrine (EPI) were observed within the hippocampus, amygdala, and the prefrontal cortex, suggesting potential involvement of dopaminergic and noradrenergic systems in regulation of aggressive behaviors.

Suppression of oxidative stress and 5-lipoxygenase activation by edaravone improves depressive-like behavior after concussion

Brain concussions are a serious public concern and are associated with neuropsychiatric disorders, such as depression. Patients with concussion who suffer from depression often experience distress. Nevertheless, few pre-clinical studies have examined concussion-induced depression, and there is little information regarding its pharmacological management. Edaravone, a free radical scavenger, can exert neuroprotective effects in several animal models of neurological disorders. However, the effectiveness of edaravone in animal models of concussion-induced depression remains unclear. In this study, we examined whether edaravone could prevent concussion-induced depression. Mice were subjected to a weight-drop injury and intravenously administered edaravone (3.0 mg/kg) or vehicle immediately after impact. Serial magnetic resonance imaging showed no abnormalities of the cerebrum on diffusion T1- and T2-weighted images. We found that edaravone suppressed concussion-induced depressive-like behavior in the forced swim test, which was accompanied by inhibition of increased hippocampal and cortical oxidative stress (OS) and suppression of 5-lipoxygenase (5-LOX) translocation to the nuclear envelope in hippocampal astrocytes. Hippocampal OS in concussed mice was also prevented by the nicotinamide adenine dinucleotide phosphate oxidase inhibitor, apocynin, and administration of BWB70C, a 5-LOX inhibitor, immediately and 24 h after injury prevented depressive-like behaviors in concussed mice. Further, antidepressant effects of edaravone were observed in mice receiving 1.0 or 3.0 mg/kg of edaravone immediately after impact, but not at a lower dose of 0.1 mg/kg. This antidepressant effect persisted up to 1 h after impact, whereas edaravone treatment at 3 h after impact had no effect on concussion-induced depressive-like behavior. These results suggest that edaravone protects against concussion-induced depression, and this protection is mediated by suppression of OS and 5-LOX translocation.

Novel mechanistic insights into treadmill exercise based rescue of social defeat-induced anxiety-like behavior and memory impairment in rats

Social defeat (SD) induced stress causes physiological and behavioral deficits in rodents, including depression and anxiety-like behaviors, as well as memory impairment. Anxiolytic and mood elevating effects of physical exercise are also known. However, rescue effect of physical exercise in social defeat-induced anxiety, depression or memory impairment has not been addressed. The role of epigenetic mechanisms that potentially contribute to these rescue or protective effects is also not known. The present study investigated the effect of moderate treadmill exercise on anxiety-like behavior and memory function in rats subjected to SD using a modified version of the resident-intruder model for social stress (defeat). Changes in histone acetylation and histone-modifying enzymes were examined in hippocampus, amygdala and frontal cortex which are considered critical for anxiety, depression and cognition. Sprague Dawley rats were randomly assigned in four groups; control, exercised, social defeat, social defeat and exercise. At the end of the SD or control exposure lasting 30 min daily for 7 days, one group of SD rats was subjected to treadmill exercise for 2 weeks, whereas the other SD group was handled without exercise. Anxiety-like behavior tests and radial arm water maze test suggested that moderate treadmill exercise rescued social defeat induced anxiety-like behavior and memory impairment. Moreover, exercise normalized SD-induced increase in oxidative stress, most likely by adjusting antioxidant response. Our data suggests involvement of epigenetic mechanisms including histone acetylation of H3 and modulation of methyl-CpG-binding in the hippocampus that might contribute to the rescue effects of exercise in SD-induced behavioral deficits in rats.

Oxidative stress and psychological disorders

Oxidative stress is an imbalance between cellular production of reactive oxygen species and the counteracting antioxidant mechanisms. The brain with its high oxygen consumption and a lipid-rich environment is considered highly susceptible to oxidative stress or redox imbalances. Therefore, the fact that oxidative stress is implicated in several mental disorders including depression, anxiety disorders, schizophrenia and bipolar disorder, is not surprising. Although several elegant studies have established a link between oxidative stress and psychiatric disorders, the causal relationship between oxidative stress and psychiatric diseases is not fully determined. Another critical aspect that needs much attention and effort is our understanding of the association between cellular oxidative stress and emotional stress. This review examines some of the recent discoveries that link oxidative status with anxiety, depression, schizophrenia and bipolar disorder. A discussion of published results and questions that currently exist in the field regarding a causal relationship between oxidative and emotional stress is also provided.

Oxidative imbalance and anxiety disorders

The oxidative imbalance appears to have an important role in anxiety development. Studies in both humans and animals have shown a strong correlation between anxiety and oxidative stress. In humans, for example, the increased malondialdehyde levels and discrepancies in antioxidant enzymes in erythrocytes have been observed. In animals, several studies also show that anxiety-like behavior is related to the oxidative imbalance. Moreover, anxiety-like behavior can be caused by pharmacological-induced oxidative stress. Studies using knockout or overexpression of antioxidant enzymes have shown a relationship between anxiety-like behavior and oxidative stress. Related factors of oxidative stress that could influence anxious behavior are revised, including impaired function of different mitochondrial proteins, inflammatory cytokines, and neurotrophic factors. It has been suggested that a therapy specifically focus in reducing reactive species production may have a beneficial effect in reducing anxiety. However, the neurobiological pathways underlying the effect of oxidative stress on anxiety symptoms are not fully comprehended. The challenge now is to identify the oxidative stress mechanisms likely to be involved in the induction of anxiety symptoms. Understanding these pathways could help to clarify the neurobiology of the anxiety disorder and provide tools for new discovery in therapies and preventive strategies.

Moderate treadmill exercise rescues anxiety and depression-like behavior as well as memory impairment in a rat model of posttraumatic stress disorder

Post-traumatic stress disorder (PTSD) is a condition which can develop from exposure to a severe traumatic event such as those occurring during wars or natural disasters. Benzodiazepines and selective serotonin reuptake inhibitors (SSRIs) are considered the gold standard for PTSD treatment, but their side effects pose a serious problem. While regular physical exercise is regarded as a mood elevator and known to enhance cognitive function, its direct role in rescuing core symptoms of PTSD including anxiety and depression-like behaviors and cognitive impairment is unclear. In the present study using the single-prolonged stress (SPS) rat model of PTSD (2h restrain, 20 min forced swimming, 15 min rest, and 1-2 min diethyl ether exposure), we examined the beneficial effect of moderate treadmill exercise on SPS-induced behavioral deficits including anxiety and depression-like behaviors and memory impairment. Male Wistar rats were randomly assigned into four groups: control (sedentary), exercised, SPS (no exercise), or SPS-exercised. Rats were exercised on a rodent treadmill for 14 consecutive days. Rats in all groups were tested for anxiety-like behaviors using open field (OF), light-dark and elevated-plus maze tests. All rats were tested for short-term and long-term memory in the radial arm water maze test. Rats were then sacrificed, blood was collected (for corticosterone levels), and individual organs (spleen, adrenals, and thymus) harvested. Results suggest that moderate physical exercise ameliorates SPS-induced behavioral deficits in rats.