Natural polyphenols in the management of major depression

Potential for diet to prevent and remediate cognitive deficits in neurological disorders

The pathophysiology of many neurological disorders involves oxidative stress, neuroinflammation, and mitochondrial dysfunction. There is now substantial evidence that diet can decrease these forms of pathophysiology, and an emerging body of literature relatedly suggests that diet can also prevent or even remediate the cognitive deficits observed in neurological disorders that exhibit such pathology (eg, Alzheimer's disease, multiple sclerosis, age-related cognitive decline, epilepsy). The current review summarizes the emerging evidence in relation to whole diets prominent in the scientific literature-ketogenic, caloric restriction, high polyphenol, and Mediterranean diets-and provides a discussion of the possible underlying neurophysiological mechanisms.

Consumption of Chlorogenic Acids through Coffee and Health Implications

Chlorogenic acids (CGA) are the main antioxidant compounds in the Western diet, due to their high concentrations in coffee associated with the high consumption of the beverage. Until about 10 years ago, like many other phenolic compounds, CGA were thought to be poorly absorbed in the human digestive system. Along the years, large amounts of information on the absorption and metabolism of these compounds have been unveiled, and today, it is known that, on average, about one third of the consumed CGA from coffee is absorbed in the human gastrointestinal tract, although large inter-individual variation exists. Considering results from in vitro animal and human studies, it is possible to conclude that the antioxidant and anti-inflammatory effects of coffee CGA are responsible for, at least to a certain extent, the association between coffee consumption and lower incidence of various degenerative and non-degenerative diseases, in addition to higher longevity.

Total saponins from the leaves of Panax notoginseng inhibit depression on mouse chronic unpredictable mild stress model by regulating circRNA expression

OBJECTIVES

Total saponins from the leaves of Panax notoginseng saponins (SLPN) could inhibit development of depression, but the underlying mechanisms remains unclear. This study aimed to address the roles of circular RNAs in depression inhibition by SLPN.

METHODS

The mouse chronic unpredictable mild stress (CUMS) model was established, which were confirmed by mouse weight, forced swimming test (FST) and tail suspension test (TST). Effects of SLPN on depression were evaluated in CUMS through these same assays. Circular RNA profiles in mouse ventral medial prefrontal cortex (VMPC) and hippocampus of CUMS mice were determined by high-through sequencing, followed by confirmation via qRT-PCR. Overexpression of mmu_circ_0001223 was done by transfection of PC12 cell through lentiviral system. Protein abundances of cAMP response element binding protein 1(CREB1) and brain-derived neurotrophic factor (BDNF) were evaluated by western blotting.

RESULTS

Mouse body weight, immobility time in FST and immobility time in TST of CUMS mice were significantly recovered by SLPN treatment. A large number of circular RNAs were differentially expressed in the ventral medial prefrontal cortex (VMPC) and hippocampus tissues of CUMS mice. Among them, mmu_circ_0001223 expression was greatly decreased in CUMS mice, but significantly elevated by SLPN treatment. The protein levels of CREB1 and BDNF were also remarkably promoted in CUMS mice by treatment of SLPN. Overexpression of mmu_circ_0001223 enhanced CREB1 and BDNF protein levels in PC12 cells.

CONCLUSION

SLPN regulate the expression of large number circular RNAs in CUMS mice, which might be important mediators of SLPN's anti-depression effects.

Antidepressant activity of an aqueous extract from okra seeds

Faced with the increasing incidence of major depression disorder (MDD) and the unsatisfactory effect of current drugs, there has been growing attention on the relation between dietary supplements and MDD prevention. In this research, the antidepressant activity of okra seed extract (OSE) was evaluated with behavioral tests including an open field test, tail suspension test (TST), forced-swimming test (FST) and novelty suppressed feeding test (NSFT) for sub-chronic treatment and chronic sleep-interruption (CSI) animal models. The chemical constituents of OSE were identified by using UPLC-DAD/Q-TOF MS. To investigate the mechanism, the prefrontal cortex and hippocampus were collected to determine neurotransmitters, total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and malondialdehyde (MDA). Blood serum was prepared for the determination of corticosterone (CORT) and adrenocorticotropic hormone (ACTH). Results demonstrated that OSE possessed an antidepressant effect in both sub-chronic treatment and CSI animal models through suppressing the hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis, alleviating oxidative stress and regulating neurotransmitter levels in the hippocampus and frontal cortex. Besides, chemical analysis based on the UPLC-DAD/ESI-Q-TOF MS approach showed that OSE mainly contained catechin and quercetin derivatives. The present study provided a scientific basis for developing okra seeds to be a dietary supplement for MDD prevention.

Role of Quercetin Benefits in Neurodegeneration

Neurodegenerative disorders are often life threatening and hired as an economic burden to the health-care system. Nutritional interventions principally involving polyphenols were practiced to arrest or reverse the age-related health disorders. Flavonoids, a class of dietary polyphenols, are rising to superstardom in preventing brain disorders with their potent antioxidant defense mechanism. Quercetin is a ubiquitous flavonoid reported to have all-natural myriad of health benefits. Citrus fruits, apple, onion, parsley, berries, green tea, and red wine comprise the major dietary supplements of quercetin apart from some herbal remedies like Ginkgo biloba. Appositeness of quercetin in reducing risks of neurodegenerative disorders, cancer, cardiovascular diseases, allergic disorders, thrombosis, atherosclerosis, hypertension, and arrhythmia, to name a few, is attributed to its highly pronounced antioxidant and anti-inflammatory properties. Neurodegeneration, characterized by progressive deterioration of the structure and function of neurons, is crucially accompanied by severe cognitive deficits. Aging is the major risk factor for neurodegenerative disorders in Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD) being coequal high hands. Oxidative stress and mitochondrial dysfunction are the key players in triggering neurodegeneration. The upsurge of neurodegenerative disorders is always appalling since there exists a paucity in effective treatment practices. Past few years' studies have underpinned the mechanisms through which quercetin boons the brain health in many aspects including betterment in cognitive output. Undoubtedly, quercetin will be escalating as an arable field, both in scientific research and in pharmacological and clinical applications.

Peanut (Arachis hypogaea L.): A Prospective Legume Crop to Offer Multiple Health Benefits Under Changing Climate

Peanut is a multipurpose oil-seed legume, which offer benefits in many ways. Apart from the peanut plant's beneficial effects on soil quality, peanut seeds are nutritious and medicinally and economically important. In this review, insights into peanut origin and its domestication are provided. Peanut is rich in bioactive components, including phenolics, flavonoids, polyphenols, and resveratrol. In addition, the involvement of peanut in biological nitrogen fixation is highly significant. Recent reports regarding peanut responses and N₂ fixation ability in response to abiotic stresses, including drought, salinity, heat stress, and iron deficiency on calcareous soils, have been incorporated. As a biotechnological note, recent advances in the development of transgenic peanut plants are also highlighted. In this context, regulation of transcriptional factors and gene transfer for the development of stress-tolerant peanut genotypes are of prime importance. Above all, this review signifies the importance of peanut cultivation and human consumption in view of the scenario of changing world climate in order to maintain food security.

Multiple Immune-Inflammatory and Oxidative and Nitrosative Stress Pathways Explain the Frequent Presence of Depression in Multiple Sclerosis

Patients with a diagnosis of multiple sclerosis (MS) or major depressive disorder (MDD) share a wide array of biological abnormalities which are increasingly considered to play a contributory role in the pathogenesis and pathophysiology of both illnesses. Shared abnormalities include peripheral inflammation, neuroinflammation, chronic oxidative and nitrosative stress, mitochondrial dysfunction, gut dysbiosis, increased intestinal barrier permeability with bacterial translocation into the systemic circulation, neuroendocrine abnormalities and microglial pathology. Patients with MS and MDD also display a wide range of neuroimaging abnormalities and patients with MS who display symptoms of depression present with different neuroimaging profiles compared with MS patients who are depression-free. The precise details of such pathology are markedly different however. The recruitment of activated encephalitogenic Th17 T cells and subsequent bidirectional interaction leading to classically activated microglia is now considered to lie at the core of MS-specific pathology. The presence of activated microglia is common to both illnesses although the pattern of such action throughout the brain appears to be different. Upregulation of miRNAs also appears to be involved in microglial neurotoxicity and indeed T cell pathology in MS but does not appear to play a major role in MDD. It is suggested that the antidepressant lofepramine, and in particular its active metabolite desipramine, may be beneficial not only for depressive symptomatology but also for the neurological symptoms of MS. One clinical trial has been carried out thus far with, in particular, promising MRI findings.

Dietary Polyphenol Intake and Depression: Results from the Mediterranean Healthy Eating, Lifestyle and Aging (MEAL) Study

Background: The epidemiological evidence for a relation between dietary polyphenol intake and depression is limited. Therefore, the aim of this study was to assess the association between habitual dietary intake of total polyphenols, their classes, subclasses and individual compounds and depressive symptoms among the participants of the Mediterranean healthy Eating, Lifestyle and Aging (MEAL) study. Methods: Demographic and dietary characteristics of 1572 adults living in southern Italy were analyzed. Food frequency questionnaires and Phenol-Explorer were used to calculate habitual dietary intakes of polyphenols. The Center for Epidemiologic Studies Depression Scale (CES-D-10) was used as screening tool for depressive symptoms. Multivariate logistic regression analyses were used to test associations and were expressed as odds ratio (OR) and 95% confidence intervals (CI). Results: A total of 509 individuals reported having depressive symptoms. Based on multivariate logistic regression analyses, total polyphenol intake was not associated with depressive symptoms. After adjustment for potential confounding factors, dietary intake of phenolic acid (OR = 0.64, 95% CI: 0.44, 0.93), flavanones (OR = 0.54, 95% CI: 0.32, 0.91), and anthocyanins (OR = 0.61, 95% CI: 0.42, 0.89) showed significant inverse association with depressive symptoms, when comparing the highest with the lowest quartile. Moreover, flavanones and anthocyanins, were associated with depressive symptoms in a dose-response manner. Among individual compounds, inverse association was observed for quercetin (OR = 0.53, 95% CI: 0.32, 0.86) and naringenin (OR = 0.51, 95% CI: 0.30, 0.85), for the highest versus lowest quartile of intake. When taking into consideration the major sources of the polyphenols, only citrus fruits and wine consumption was inversely associated with depressive symptoms (Q4 vs. Q1: OR= 0.51, 95% CI: 0.35, 0.75; Q4 vs. Q1: OR = 0.53, 95% CI: 0.38, 0.74, respectively). Conclusions: Higher dietary intake of flavonoid may be inversely associated with depressive symptoms. Further studies are needed to definitively confirm these observed associations.

Polyphenolic Compounds Alter Stress-Induced Patterns of Global DNA Methylation in Brain and Blood

SCOPE

Stress is a known contributor to various forms of disease in humans and animals, although mechanisms are still unknown. In animals, psychosocial stress-induced depression/anxiety phenotypes are coincidental with increased inflammation in both brain and blood. The authors recently showed that a novel treatment with a select bioactive polyphenol preparation promotes resilience to stress-mediated depression/anxiety phenotypes mice. Moreover, selective bioactive phenolic compounds within the polyphenol preparation are identified that are effective in mitigating the behavioral effects of bone marrow transplantation from stressed mice.

METHODS AND RESULTS

Here, an animal model of adult stress and bone marrow transplantation is used to identify an epigenetic signature of repeated social defeat stress (RSDS) that is passed through bone marrow hematopoietic progenitor cells to naïve mice, revealing the maintenance of epigenetic memory following stress both centrally and peripherally. Further, polyphenols are administered to naïve and stress-susceptible mice, demonstrating that polyphenol treatment in mice from both susceptible and naïve donors alters global DNA methylation in the central nervous system and periphery and likewise has an effect on human blood cells after immune challenge.

CONCLUSIONS

Findings highlight the enduring molecular memory of stress and the possible mechanism by which select bioactive polyphenols may promote resiliency to stress. Polyphenols may be an efficacious alternative to traditional pharmacological treatments in psychiatry.

Pharmacokinetic Study of 7 Compounds Following Oral Administration of Fructus Aurantii to Depressive Rats

In the present study, the pharmacokinetics of multi-components (naringenin, nobiletin, meranzin hydrate, narirutin, naringin, hesperidin, and neohesperidin) were investigated in acute depressive rats following oral administration of Fructus Aurantii (Zhi-Qiao, ZQ) extract (20 g/kg). A rapid and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established to quantitatively or qualitatively analyze the 7 absorbed ingredients in the plasma, hippocampus and cortex of acute depressive rats. Biological samples were separated on a 300SB-C18 column, and the 7 compounds were detected with sequential positive and negative ionization modes. Our results confirmed that ZQ has antidepressant effects by decreasing the immobility time. In addition, this validated method showed good linearity (r ≥ 0.9987), and the lower limits of quantification were 2.73–16.38 ng/mL for the 7 analytes. This method successfully determined the pharmacokinetics of the 7 compounds and separated two pairs of isomers in plasma of acute depressive rats following oral administration of ZQ extracts. The 7 active ingredients were also identified as marked compounds in target tissues and should be further examined in pharmacokinetic studies with acute depressive rats. So, pharmacokinetic compounds were precisely linked with the antidepressant effect of ZQ in our study. This relationship is well-understood and contributes to the application of Traditional Chinese Medicine (TCM).

Ethnopharmacological Approaches for Dementia Therapy and Significance of Natural Products and Herbal Drugs

Dementia is a clinical syndrome wherein gradual decline of mental and cognitive capabilities of an afflicted person takes place. Dementia is associated with various risk factors and conditions such as insufficient cerebral blood supply, toxin exposure, mitochondrial dysfunction, oxidative damage, and often coexisting with some neurodegenerative disorders such as Alzheimer's disease (AD), Huntington's disease (HD), and Parkinson's disease (PD). Although there are well-established (semi-)synthetic drugs currently used for the management of AD and AD-associated dementia, most of them have several adverse effects. Thus, traditional medicine provides various plant-derived lead molecules that may be useful for further medical research. Herein we review the worldwide use of ethnomedicinal plants in dementia treatment. We have explored a number of recognized databases by using keywords and phrases such as “dementia”, “Alzheimer's,” “traditional medicine,” “ethnopharmacology,” “ethnobotany,” “herbs,” “medicinal plants” or other relevant terms, and summarized 90 medicinal plants that are traditionally used to treat dementia. Moreover, we highlight five medicinal plants or plant genera of prime importance and discuss the physiological effects, as well as the mechanism of action of their major bioactive compounds. Furthermore, the link between mitochondrial dysfunction and dementia is also discussed. We conclude that several drugs of plant origin may serve as promising therapeutics for the treatment of dementia, however, pivotal evidence for their therapeutic efficacy in advanced clinical studies is still lacking.

Epigenetic modulation of inflammation and synaptic plasticity promotes resilience against stress in mice

Major depressive disorder is associated with abnormalities in the brain and the immune system. Chronic stress in animals showed that epigenetic and inflammatory mechanisms play important roles in mediating resilience and susceptibility to depression. Here, through a high-throughput screening, we identify two phytochemicals, dihydrocaffeic acid (DHCA) and malvidin-3′-O-glucoside (Mal-gluc) that are effective in promoting resilience against stress by modulating brain synaptic plasticity and peripheral inflammation. DHCA/Mal-gluc also significantly reduces depression-like phenotypes in a mouse model of increased systemic inflammation induced by transplantation of hematopoietic progenitor cells from stress-susceptible mice. DHCA reduces pro-inflammatory interleukin 6 (IL-6) generations by inhibiting DNA methylation at the CpG-rich IL-6 sequences introns 1 and 3, while Mal-gluc modulates synaptic plasticity by increasing histone acetylation of the regulatory sequences of the Rac1 gene. Peripheral inflammation and synaptic maladaptation are in line with newly hypothesized clinical intervention targets for depression that are not addressed by currently available antidepressants.

Polyphenols have partial antidepressant effect without known mechanism. Here, the authors identify two phytochemicals from bioactive dietary polyphenols, show their antidepressant effect in a rodent model of depression, and that this effect is mediated by epigenetic and anti-inflammatory mechanisms.

Neuroplasticity-related mechanisms underlying the antidepressant-like effects of traditional herbal medicines

Traditional herbal medicine can offer efficacious and safe alternative pharmacotherapies for depression. The ability of an herbal medicine to produce neuroadaptive processes, that enhance neuroplasticity and cellular resilience in response to chronic stress, may point to its antidepressant potential. We suggest that among many investigated herbal medicines, those that can enhance neuroplasticity may have stronger therapeutic potential. The current article presents a summary of traditional herbal medicines, which are thought to exert antidepressant-like effects in chronic stress models via neuroplasticity enhancement. Brain-derived neurotrophic factor (BDNF) is a biomarker for neuroplasticity-related mechanisms compromised in depression and recovered by conventional antidepressants, including synaptic plasticity, cell survival, neurogenesis and spine formation. We therefore presumed that if an herbal medicine up-regulates BDNF in the hippocampus and/or prefrontal cortex (PFC), its antidepressant-like effect is mediated, at least partially, via neuroplasticity-related mechanisms. Literature search was performed using the general terms depression, stress, neuroplasticity and herbal medicines. Screening of retrieved preclinical studies revealed 30 traditional herbal medicines: 8 single herbs, 15 bioactive constituents, and 7 herbal formulas. The antidepressant-like effects of these medicines were associated with reversal of chronic stress-induced impairment in neuroplasticity, most notably by BDNF up-regulation, activation of BDNF downstream signaling pathways and increase in neurogenesis in the hippocampus and/or PFC/frontal cortex. In light of the ability of these medicines to enhance neuroplasticity, we suggest that they may be suitable candidates for clinical investigation in depressed individuals. Once their efficacy, tolerability and safety will be substantiated, they may serve as natural alternatives to conventional antidepressants.

Resveratrol for Alzheimer's disease

The amyloid hypothesis suggests that the progressive accumulation and deposition of central nervous system (CNS) amyloid with aging is the proximate cause of Alzheimer's disease (AD). Thus, targeting molecular mechanisms of aging may be a viable treatment approach. Caloric restriction prevents diseases of aging, including AD, in animal models, perhaps by activation of sirtuins. The sirtuins (e.g., mammalian SIRT1) are deacetylases that link energy balance (NAD+ /NADH) to regulation of gene transcription. Resveratrol is a potent activator of SIRT1, and thus may mimic caloric restriction to prevent diseases of aging. We conducted a randomized, double-blind, placebo-controlled, phase II trial of resveratrol for individuals with mild-to-moderate AD. Resveratrol (1) is detectable in cerebrospinal fluid (at low nanomolar levels), (2) is safe and well tolerated, (3) alters AD biomarker trajectories, (4) preserves blood-brain barrier integrity, and (5) modulates the CNS immune response. Further studies are needed to determine the safety and efficacy of resveratrol and the validity of this approach in the treatment and prevention of AD and other diseases of aging.

Neurobehavioural evaluation of resveratrol in murine models of anxiety and schizophrenia

Resveratrol, a caloric restriction mimetic, is a naturally occurring polyphenolic compound with antioxidant and anti-inflammatory properties. Oxidative stress has been implicated in the etiology of a number of neuropsychiatric disorders including generalized anxiety and schizophrenia. This study investigated the anxiolytic and antipsychotic potentials of resveratrol in murine models of anxiety and schizophrenia. Mice were pretreated with resveratrol (200 and 400 mg/kg) in 1% carboxymethyl cellulose for 14 days and subjected to behavioural tests on the 15th day. Anxiolytic activity of resveratrol was determined using the hole board and staircase tests while its anti-psychotic property was evaluated via apormorphine induced stereotypy and swim-induced grooming tests. Although resveratrol did not significantly reduce the mean number of head dips at doses used in the hole board test, it significantly (p < 0.01) decreased the mean episodes of rearing without significantly altering the total number of upward steps climbed in the staircase test. Resveratrol significantly (p < 0.05) reduced the mean climbing scores in the first ten minutes of the apormorphine induced stereotypic climbing and significantly decreased (p < 0.01) episodes and total duration of swim induced grooming in mice. Administration of resveratrol at doses used in this study produced anxiolysis and anti-psychotic effects in mice.

Chlorogenic Acid and Mental Diseases: From Chemistry to Medicine

BACKGROUND

At present, much attention has been focused on the beneficial effects of natural products on the human health due to their high efficacy and low adverse effects. Among them, polyphenolic compounds are known as one of the most important and common classes of natural products, which possess multiple range of health-promotion effects including anti-inflammatory and antioxidant activities. A plethora of scientific evidence has shown that polyphenolic compounds possess beneficial effects on the central nervous system.

METHODS

Data were collected from Web of Science (ISI Web of Knowledge), Medline, Pubmed, Scopus, Embase, and BIOSIS Previews (from 1950 to 2015), through searching of these keywords: "chlorogenic acid and mental diseases" and "chlorogenic acid and neuroprotection".

RESULTS

Chlorogenic acid is known as one of the most common polyphenolic compounds, and is found in different types of fruits and vegetables, spices, wine, olive oil, as well as coffee. The potential neuroprotective effects of chlorogenic acid have been highlighted in several in vitro and in vivo studies. This review critically analyses the available scientific evidence regarding the neuroprotective effects of chlorogenic acid, and its neuropharmacological mechanisms of action. In addition, we also discuss its biosynthesis, sources, bioavailability and metabolism, to provide a broad perspective of the therapeutic implications of this compound in brain health and disease.

CONCLUSION

The present review showed that chlorogenic acid possesses neuroprotective effects under the both in vitro and in vivo models.

Curcumin loaded self assembled lipid-biopolymer nanoparticles for functional food applications

The supramolecular nano-assemblies formed by electrostatic interactions of two oppositely charged lipid and polymer have been made and used as nanocarriers for curcumin to address its bioavailability and solubility issues. These curcumin encapsulated nano-supramolecular assemblies were characterized with respect to their size (dynamic light scattering), morphology (TEM, SEM), zeta potential (Laser Doppler Velocimetry), encapsulation efficiency (EE), curcumin loading (CL) etc. Stability of the nano-assemblies was assessed at different storage times as a function of varying pH and temperature. The physicochemical characterization of nano-assemblies was performed using Fourier Transform Infra Red Spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC). The in-vitro antioxidant lipid peroxidation (TBARS), radical scavenging (DPPH, NO, H2O2, reducing power) activity assays of powdered curcumin and nano-encapsulated curcumin were performed. It was found that nano-encapsulated curcumin were roughly spherical in shape, presented high positive zeta potential (>30 mV), monodisperse (polydispersity index <0.3), amorphous in nature, stable in the pH range of 2-6 and have enhanced antioxidant potency in comparison to crystalline curcumin in aqueous media. In conclusion, the curcumin encapsulated nanocarriers system has great potential as functional food ingredient of natural origin.

The effect of Polygonum minus extract on cognitive and psychosocial parameters according to mood status among middle-aged women: a randomized, double-blind, placebo-controlled study

Background

Polygonum minus (PM) or locally known in Malaysia, as “kesum” is rich in micronutrients and natural antioxidants. However, its beneficial effect on outcome associates with oxidative stress including cognitive function is yet to be discovered. We assessed the efficacy of PM extract (LineMinus™) on cognitive function and psychosocial status among middle-aged women in Klang Valley of Malaysia.

Methods

A randomized, double-blind, placebo-controlled trial among 35 healthy middle-aged women was performed, and subjects were randomized to receive either 250 mg PM or placebo of 100 mg maltodextrin each were taken twice daily for 6 weeks. Subjects were assessed for neuropsychological test, psychosocial status, and anthropometric at baseline, week 3, and week 6. Biomarkers were also determined at baseline and week 6.

Results

The supplementation of PM showed significant intervention effect on Digit Span test (P<0.05) social functioning domain of 36-Item Short Form Health Survey (P<0.05) among subjects with mood disturbance. While, among subjects with good mood, PM supplementation improved Wechsler Abbreviated Scale of Intelligence (WASI) for IQ verbal (P=0.016) and Full Scale IQ of WASI (P=0.004). There were no adverse effects reported for the supplementation as indicated using biomarkers, including liver function and clinical symptoms.

Conclusion

Supplementation of PM is safe to be consumed for 6 weeks, with potential benefits to attention, short-term memory, improved quality of life, and mood, as well as IQ.

The therapeutic detoxification of chlorogenic acid against acetaminophen-induced liver injury by ameliorating hepatic inflammation

Chlorogenic acid (CGA) has been reported to prevent acetaminophen (AP)-induced hepatotoxicity when mice were pre-administered orally with CGA for consecutive 7days before AP intoxication in our previous study. This study investigated the therapeutic detoxification of CGA against AP-induced hepatotoxicity and the engaged mechanism. The mice were orally administered with CGA (10, 20, 40mg/kg) at 1h after given AP (400mg/kg), and another 3h later the mice were killed for the following experiments. Results of serum transaminases analysis and histological evaluation demonstrated the detoxification of CGA against AP-induced hepatotoxicity. CGA reduced AP-induced the increased myeloperoxidase (MPO) enzymatic activity and its expression. CGA reduced AP-induced the increased liver expression of toll-like receptor (TLR)-3/4 and MyD88, and the increased phosphorylation of inhibitor of kappa B (IκB) and p65 subunit of nuclear factor κB (NFκB). CGA reduced AP-induced the increased NFκBp65 expression in nucleus. In addition, CGA reduced AP-induced the increased serum levels and liver mRNA expression of tumor necrosis factor alpha (TNFα), interleukin (IL)-1β, IL-6, monocyte chemoattractant protein-1 (MCP-1), and keratinocyte chemoattractant (KC). Taken together, our results demonstrate the therapeutic detoxification of CGA against AP-induced liver injury, and TLR3/4 and NFκB signaling pathway are involved in such process.

Psychiatric Disorders and Polyphenols: Can They Be Helpful in Therapy?

The prevalence of psychiatric disorders permanently increases. Polyphenolic compounds can be involved in modulation of mental health including brain plasticity, behaviour, mood, depression, and cognition. In addition to their antioxidant ability other biomodulating properties have been observed. In the pathogenesis of depression disturbance in neurotransmitters, increased inflammatory processes, defects in neurogenesis and synaptic plasticity, mitochondrial dysfunction, and redox imbalance are observed. Ginkgo biloba, green tea, and Quercus robur extracts and curcumin can affect neuronal system in depressive patients. ADHD patients treated with antipsychotic drugs, especially stimulants, report significant adverse effects; therefore, an alternative treatment is searched for. An extract from Ginkgo biloba and from Pinus pinaster bark, Pycnogenol, could become promising complementary supplements in ADHD treatment. Schizophrenia is a devastating mental disorder, with oxidative stress involved in its pathophysiology. The direct interference of polyphenols with schizophrenia pathophysiology has not been reported yet. However, increased oxidative stress caused by haloperidol was inhibited ex vivo by different polyphenols. Curcumin, extract from green tea and from Ginkgo biloba, may have benefits on serious side effects associated with administration of neuroleptics to patients suffering from schizophrenia. Polyphenols in the diet have the potential to become medicaments in the field of mental health after a thorough study of their mechanism of action.

Identification of the chemical constituents in aqueous extract of Zhi-Qiao and evaluation of its antidepressant effect

The immature fruit of Citrus aurantium L. (Zhi-Qiao, ZQ) has been used as a traditional medicine in China. Our previous study has shown that ZQ decoction may contribute to the antidepressant-like action of Chaihu-Shu-Gan-San. However, there are no reports on the chemical constituents of ZQ aqueous extract or its anti-depression effects. Firstly, this research reported the on-line identification of the chemical constituents in the aqueous extract of ZQ by coupling ultra-performance liquid chromatography/time-of-flight mass spectrometry (UPLC-Q-TOF/MS). A total of 31 chemical constituents were identified in ZQ aqueous extract, including one tannic acid, five flavones, 13 flavanones, one limonoid, three coumarins, three cyclic peptides, and five polymethoxylated flavonoids. The antidepressant effect of ZQ aqueous extract was evaluated in vivo and the results indicated that the mice immobility time during the forced swimming test and the tail suspension test were significantly reduced with ZQ treatment. MTT assays showed both ZQ aqueous extract and its major constituents (naringin, hesperidin, neohesperidin, and nobiletin) had neuroprotective effect on corticosterone-induced neurotoxicity in PC12 cells. The in vivo and in vitro results suggest that ZQ has an antidepressant effect.

An Increase in Plasma Homovanillic Acid with Cocoa Extract Consumption Is Associated with the Alleviation of Depressive Symptoms in Overweight or Obese Adults on an Energy Restricted Diet in a Randomized Controlled Trial

BACKGROUND

Obesity has been associated with various health disorders, including psychological alterations. Cocoa consumption and weight management may produce a beneficial effect on these problems.

OBJECTIVE

The purpose of this study was to investigate the effect of cocoa extract supplementation as part of an energy-restricted diet on psychological status and peripheral dopaminergic activity in overweight or obese middle-aged subjects.

METHODS

In a 4-wk, double-blind, randomized, placebo-controlled parallel nutritional intervention, 22 men and 25 women [mean ± SD age: 57 ± 5 y; body mass index (kg/m2): 30.6 ± 2.3] were studied. After a 1-wk run-in period, volunteers consumed 15% energy-restricted diets; one-half of the volunteers were randomly assigned to receive ready-to-eat meals supplemented with 1.4 g cocoa extract/d (645 mg total polyphenols/d), whereas the rest of the volunteers received the same meals without cocoa supplementation. Plasma monoamines [dopamine, dopac, and homovanillic acid (HVA)], monoamine oxidase (MAO), and psychological status (anxiety and depressive symptoms) were analyzed in fasting participants at baseline and endpoint. Data were analyzed over time, and regression and correlation analyses were conducted to determine the relation between variables.

RESULTS

Depressive symptoms decreased in both groups after the intervention (control: -9.4%, P < 0.001; cocoa: -6.3%, P = 0.008), but anxiety symptoms did not. The increase in plasma HVA was 11.5% greater in the cocoa group than in the control group (P = 0.016), but plasma dopamine, dopac, and MAO changes did not differ between groups. A negative relation between changes in depressive symptoms and changes in plasma HVA was observed in the cocoa group (β = -0.39, P = 0.029). Moreover, the change in plasma dopamine was positively associated with the change in methyl-catechin-O-glucoronide in the cocoa-supplemented group (r = 0.69, P = 0.019).

CONCLUSION

The intake of cocoa extract by participants consuming a 15% energy-restricted diet contributed to an increase in plasma HVA concentrations. This change was associated with a reduction in depressive symptoms, suggesting a potential effect of cocoa extract intake on this relation. The present results are secondary analyses of a clinical trial that was registered at www.clinicaltrials.gov as NCT01596309.

Natural environments, ancestral diets, and microbial ecology: is there a modern "paleo-deficit disorder"? Part II

Famed microbiologist René J. Dubos (1901–1982) was an early pioneer in the developmental origins of health and disease (DOHaD) construct. In the 1960s, he conducted groundbreaking research concerning the ways in which early-life experience with nutrition, microbiota, stress, and other environmental variables could influence later-life health outcomes. He recognized the co-evolutionary relationship between microbiota and the human host. Almost 2 decades before the hygiene hypothesis, he suggested that children in developed nations were becoming too sanitized (vs. our ancestral past) and that scientists should determine whether the childhood environment should be “dirtied up in a controlled manner.” He also argued that oft-celebrated growth chart increases via changes in the global food supply and dietary patterns should not be equated to quality of life and mental health. Here in the second part of our review, we reflect the words of Dubos off contemporary research findings in the areas of diet, the gut-brain-axis (microbiota and anxiety and depression) and microbial ecology. Finally, we argue, as Dubos did 40 years ago, that researchers should more closely examine the relevancy of silo-sequestered, reductionist findings in the larger picture of human quality of life. In the context of global climate change and the epidemiological transition, an allergy epidemic and psychosocial stress, our review suggests that discussions of natural environments, urbanization, biodiversity, microbiota, nutrition, and mental health, are often one in the same.

Nutritional psychiatry research: an emerging discipline and its intersection with global urbanization, environmental challenges and the evolutionary mismatch

In 21st-century public health, rapid urbanization and mental health disorders are a growing global concern. The relationship between diet, brain function and the risk of mental disorders has been the subject of intense research in recent years. In this review, we examine some of the potential socioeconomic and environmental challenges detracting from the traditional dietary patterns that might otherwise support positive mental health. In the context of urban expansion, climate change, cultural and technological changes and the global industrialization and ultraprocessing of food, findings related to nutrition and mental health are connected to some of the most pressing issues of our time. The research is also of relevance to matters of biophysiological anthropology. We explore some aspects of a potential evolutionary mismatch between our ancestral past (Paleolithic, Neolithic) and the contemporary nutritional environment. Changes related to dietary acid load, advanced glycation end products and microbiota (via dietary choices and cooking practices) may be of relevance to depression, anxiety and other mental disorders. In particular, the results of emerging studies demonstrate the importance of prenatal and early childhood dietary practices within the developmental origins of health and disease concept. There is still much work to be done before these population studies and their mirrored advances in bench research can provide translation to clinical medicine and public health policy. However, the clear message is that in the midst of a looming global epidemic, we ignore nutrition at our peril.

Behavioural screening of zebrafish using neuroactive traditional Chinese medicine prescriptions and biological targets

The mechanism of the therapeutic action of antidepressants remains uncertain in traditional Chinese medicine (TCM). In this study, we selected 7 classical TCM prescriptions and utilised an automatic video-tracking system to monitor the rest/wake behaviour of larval zebrafish at 4 days post-fertilisation (dpf) for 48 hours. We found that the curative effects of the prescriptions were dose-dependent. K-means clustering was performed according to the shared behavioural phenotypes of the zebrafish. The results revealed that the rest/wake behavioural profiles induced by the same class of prescriptions were similar. A correlation analysis was conducted between the TCM prescriptions and the known compounds. The results showed that the TCM prescriptions correlated well with some well-known compounds. Therefore, we predicted that they may share a similar mechanism of action. This paper describes the first study to combine TCM research with zebrafish rest/wake behaviour in vivo and presents a powerful approach for the discovery of the mechanism of action of TCM prescriptions.

Oxidative & nitrosative stress in depression: why so much stress?

Many studies support a crucial role for oxidative & nitrosative stress (O&NS) in the pathophysiology of unipolar and bipolar depression. These disorders are characterized inter alia by lowered antioxidant defenses, including: lower levels of zinc, coenzyme Q10, vitamin E and glutathione; increased lipid peroxidation; damage to proteins, DNA and mitochondria; secondary autoimmune responses directed against redox modified nitrosylated proteins and oxidative specific epitopes. This review examines and details a model through which a complex series of environmental factors and biological pathways contribute to increased redox signaling and consequently increased O&NS in mood disorders. This multi-step process highlights the potential for future interventions that encompass a diverse range of environmental and molecular targets in the treatment of depression.

Antidepressant effects of resveratrol in an animal model of depression

Resveratrol (3,4',5-trihydroxy-trans-stilbene) is a natural non-flavonoid polyphenol antioxidant extracted from red grapes in the processing of wine. Initially it was studied for its potential as anticancer drug, and later was found to reduce cardiovascular disease. More recently resveratrol was shown to alleviate depressive-like symptoms induced by stress or other means in mice and rats. The major purpose of this study was to investigate whether resveratrol would manifest an antidepressant effect in Wistar-Kyoto (WKY) rats, a putative and non-induced animal model of depression, and whether this effect might be associated with an increase in hippocampal and frontal cortical brain-derived neurotrophic factor (BDNF), a protein implicated in chronic effects of many antidepressants. Adult male WKY rats were injected with two doses of resveratrol (10 and 40 mg/kg, i.p.) and their behavior in the open field locomotor activity (LMA), forced swim test (FST: a measure of helplessness), and sucrose preference test (SPT: a measure of anhedonia) was evaluated after a single acute injection or following 7 days of daily treatment. Both acute and chronic administration of resveratrol resulted in a dose-dependent decrease in FST. However, only chronic resveratrol resulted in dose-dependent increase in sucrose consumption. LMA was not affected by any treatment. Parallel to the observed behavioral effects the level of hippocampal, but not frontal cortical, BDNF was also dose-dependently elevated after chronic resveratrol administration. These findings indicate an antidepressant-like effect of resveratrol in an animal model of depression possibly via activation of hippocampal BDNF, and suggest therapeutic potential of resveratrol in at least a subpopulation of depressed patients.

Fermented foods, microbiota, and mental health: ancient practice meets nutritional psychiatry

The purposeful application of fermentation in food and beverage preparation, as a means to provide palatability, nutritional value, preservative, and medicinal properties, is an ancient practice. Fermented foods and beverages continue to make a significant contribution to the overall patterns of traditional dietary practices. As our knowledge of the human microbiome increases, including its connection to mental health (for example, anxiety and depression), it is becoming increasingly clear that there are untold connections between our resident microbes and many aspects of physiology. Of relevance to this research are new findings concerning the ways in which fermentation alters dietary items pre-consumption, and in turn, the ways in which fermentation-enriched chemicals (for example, lactoferrin, bioactive peptides) and newly formed phytochemicals (for example, unique flavonoids) may act upon our own intestinal microbiota profile. Here, we argue that the consumption of fermented foods may be particularly relevant to the emerging research linking traditional dietary practices and positive mental health. The extent to which traditional dietary items may mitigate inflammation and oxidative stress may be controlled, at least to some degree, by microbiota. It is our contention that properly controlled fermentation may often amplify the specific nutrient and phytochemical content of foods, the ultimate value of which may associated with mental health; furthermore, we also argue that the microbes (for example, Lactobacillus and Bifidobacteria species) associated with fermented foods may also influence brain health via direct and indirect pathways.

Piperine potentiates the antidepressant-like effect of trans-resveratrol: involvement of monoaminergic system

Major depression is characterized by dysfunction of neuroendocrine and immune networks. Trans-resveratrol, a phenolic compound presented in polygonum cuspidatum, was demonstrated previously to exert antidepressant-like effects through regulating monoaminergic system, oxidative/antioxidant defense and inflammatory response. The present study investigated the synergistic antidepressant-like effect of trans-resveratrol and piperine, a bioavailability enhancer, in mice and explored the possible mechanism. Trans-resveratrol was shown to reduce the immobility time both in the tail suspension and forced swimming tests (TST and FST). But the maximal inhibition was nearly 60% even if the doses were increased by 160 mg/kg; while piperine produced weak antidepressant-like effects in these two models. The interaction between trans-resveratrol and piperine was shown a clear-cut synergistic effect as evidenced by an isobolographic analysis. The further study suggested that the anti-immobility response from the subthreshold dose of piperine (2.5 mg/kg) and low doses of trans-resveratrol (10 and 20 mg/kg) was abolished by pretreatment with para-chlorophenylalanine (PCPA, 300 mg/kg, i.p.) in TST and FST, indicating the involvement of serotonergic system. Moreover, treatment with the subthreshold dose of piperine and low doses of trans-resveratrol attenuated reserpine-induced hypothermia and ptosis arguing for the relevance of noradrenaline. Additional evidence from neurochemical (monoamines in the frontal cortex, hippocampus, and hypothalamus) and biochemical (monoamine oxidase, MAO activity) assays corroborated the synergistically elevated monoaminergic system after co-treatment with trans-resveratrol and piperine. The present results indicate the effect of trans-resveratrol combined with piperine on depressive-like behaviors may be partly due to the potentiated activation of monoaminergic system in the brain. Further studies are necessary to elucidate the involvement of the oxidative/nitrosative stress, inflammatory and neuroprotective pathway in the antidepressant-like effect of this combination. The synergistic effect obtained from the combination may provide innovative clues for designing novel antidepressants with high efficacy and low side effects.