Quercetin protects against stress-induced anxiety- and depression-like behavior and improves memory in male mice

Endoplasmic reticulum stress, autophagy, neuroinflammation, and sigma 1 receptors as contributors to depression and its treatment

The etiological factors contributing to depression and other neuropsychiatric disorders are largely undefined. Endoplasmic reticulum stress pathways and autophagy are well-defined mechanisms that play critical functions in recognizing and resolving cellular stress and are possible targets for the pathophysiology and treatment of psychiatric and neurologic illnesses. An increasing number of studies indicate the involvement of endoplasmic reticulum stress and autophagy in the control of neuroinflammation, a contributing factor to multiple neuropsychiatric illnesses. Initial inflammatory triggers induce endoplasmic reticulum stress, leading to neuroinflammatory responses. Subsequently, induction of autophagy by neurosteroids and other signaling pathways that converge on autophagy induction are thought to participate in resolving neuroinflammation. The aim of this review is to summarize our current understanding of the molecular mechanisms governing the induction of endoplasmic reticulum stress, autophagy, and neuroinflammation in the central nervous system. Studies focused on innate immune factors, including neurosteroids with anti-inflammatory roles will be reviewed. In the context of depression, animal models that led to our current understanding of molecular mechanisms underlying depression will be highlighted, including the roles of sigma 1 receptors and pharmacological agents that dampen endoplasmic reticulum stress and associated neuroinflammation.

GABAergic implications in anxiety and related disorders

Evidence indicates that anxiety disorders arise from an imbalance in the functioning of brain circuits that govern the modulation of emotional responses to possibly threatening stimuli. The circuits under consideration in this context include the amygdala's bottom-up activity, which signifies the existence of stimuli that may be seen as dangerous. Moreover, these circuits encompass top-down regulatory processes that originate in the prefrontal cortex, facilitating the communication of the emotional significance associated with the inputs. Diverse databases (e.g., Pubmed, ScienceDirect, Web of Science, Google Scholar) were searched for literature using a combination of different terms e.g., "anxiety", "stress", "neuroanatomy", and "neural circuits", etc. A decrease in GABAergic activity is present in both anxiety disorders and severe depression. Research on cerebral functional imaging in depressive individuals has shown reduced levels of GABA within the cortical regions. Additionally, animal studies demonstrated that a reduction in the expression of GABAA/B receptors results in a behavioral pattern resembling anxiety. The amygdala consists of inhibitory networks composed of GABAergic interneurons, responsible for modulating anxiety responses in both normal and pathological conditions. The GABAA receptor has allosteric sites (e.g., α/γ, γ/β, and α/β) which enable regulation of neuronal inhibition in the amygdala. These sites serve as molecular targets for anxiolytic medications such as benzodiazepine and barbiturates. Alterations in the levels of naturally occurring regulators of these allosteric sites, along with alterations to the composition of the GABAA receptor subunits, could potentially act as mechanisms via which the extent of neuronal inhibition is diminished in pathological anxiety disorders.

Quercetin's Restorative Properties in Male Mice with 3-Nitropropionic Acid-induced Huntington-like Symptoms: Molecular Docking, Behavioral, and Biochemical Assessment

The neurotoxicity of 3-Nitropropionic acid (3-NP) is well known. Herein, the prophylactic versus therapeutic effects of quercetin (QCT) were investigated against 3-NP-induced behavioral anomalies and oxidative neural damage. Thirty male mice were assigned into five groups; the negative control group, the QCT group (25 mg/kg/day, p.o. for 21 days), the 3-NP group (17 days), the prophylactic group (QCT administration for 14 consecutive days, and then 3-NP was administrated), the therapeutic group (3-NP was administrated and then QCT for 21 days). At the end of the animal treatment, behavioral studies were assessed. Subsequently, the brain sample tissues were assessed for oxidative stress-related parameters and histological evaluation. Moreover, the potential interaction between 3-NP and tumor necrosis factor-alpha (TNF-α) was evaluated by using a molecular docking study. 3-NP markedly led to neurotoxicity which was indicated by behavioral deficits (motor behavior, depression-like behavior, memory dysfunction, and passive avoidance) and oxidative damage. Blind and targeted molecular docking results showed good interaction between 3-NP and TNF-α. However, the prophylactic effects of QCT were superior to the therapeutic effects for attenuating 3-NP-induced neurobehavioral and oxidative neural changes in experimental mice, which histological changes of the brain's striatum region approved our findings. Taken together, the antioxidant activity of QCT remarkably could attenuate 3-NP-induced neurobehavioral deficits and mitochondrial dysfunctions in mice.

The monoaminergic pathways are involved in the antidepressant-like effect of quercetin

Quercetin, a plant-derived flavonoid, is an antioxidant and has demonstrated antidepressant and anti-inflammatory activities in several animal models. However, there is scanty information on the underlying mechanisms of its antidepressant property. This present study aimed at assessing the involvement of monoaminergic systems in the antidepressant-like activity of quercetin in experimental animals. Mice received varying doses of quercetin (25, 50 &100 mg/kg daily) and were then subjected to open field test (OPF), despair tests, the reserpine test, and the yohimbine lethality test (YLT). In addition, monoaminergic involvement was investigated by combining quercetin (100 mg/kg) with dopaminergic antagonists (haloperidol and sulpiride), adrenergic blockers (prazosin, propranolol and yohimbine), and serotonergic blockers/inhibitors (metergoline). The results showed that quercetin produced significant anti-immobility effects in the forced swim test (FST) and tail suspension test (TST), suggesting antidepressant activity. In addition, the potentiation of yohimbine lethality by quercetin further indicates its antidepressant-like property. This antidepressant action demonstrated was, however, blocked when quercetin was co-administered with dopaminergic, adrenergic and serotonergic antagonists, suggesting involvement of the monoaminergic system in the antidepressant action of quercetin. Nevertheless, quercetin did not significantly alter the locomotor activity of mice, which implies lack of stimulant effect. Taken together, these outcomes suggest that monoaminergic systems are likely involved in the anti-depressant effect of quercetin in mice.

Glycitein prevents reserpine-induced depression and associated comorbidities in mice: modulation of lipid peroxidation and TNF-α levels

Depression is a debilitating mood disorder affecting millions worldwide and continues to pose a significant global health burden. Due to the multifaceted nature of depression, the current treatment regimens are not up to mark in terms of their multitargeting potential and least side effect profile. Molecules within the isoflavone class demonstrate promising potential in alleviating depression and associated conditions, offering a multifaceted approach to manage mental health concerns. Therefore, the current study was designed to explore the potential of glycitein, an isoflavone in managing reserpine-induced depression and associated comorbidities in mice. Reserpine (0.5 mg/kg; i.p.) administration for the first 3 days induced depression and associated comorbidities as evidenced by increased immobility time in forced swim test (FST) and tail suspension test (TST), along with reduced locomotor activity in the open field test (OFT) and increased latency to reach the platform in the Morris water maze (MWM) test. Reserpine treatment also upregulated and downregulated the brain thiobarbituric acid reactive substance (TBARS) and glutathione (GSH) levels, respectively. Furthermore, reserpine administration also uplifted the level of TNF-α in the serum samples. Glycitein (3 mg/kg and 6 mg/kg; p.o.) treatment for 5 days prevented the depressive effect of reserpine. It also improved the spatial memory at both dose levels. Moreover, in biochemical analysis, glycitein also reduced the brain TBARS and serum tumor necrosis factor-alpha (TNF-α) levels. Whereas, no significant effect was seen on the brain GSH level. Glycitein (6 mg/kg) was found to be more effective than the 3 mg/kg dose of glycitein. Overall results delineate that glycitein has the potential to manage depression and impaired memory by inhibiting lipid peroxidation and inflammatory stress.

Exploring the mechanism of Si-Ni-San against depression by UPLC-Q-TOF-MS/MS integrated with network pharmacology: experimental research

Background

Depression is becoming an urgent mental health problem. Si-Ni-San has been widely used to treat depression, yet its underlying pharmacological mechanism is poorly understood. Thus, we aim to explore the antidepressant mechanism of Si-Ni-San by chemical analysis and in-silico methods.

Methods

Compounds in Si-Ni-San were determined by ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS). Then, bioactive compounds were obtained from Traditional Chinese Medicines for Systems Pharmacology Database and Analysis Platform and SwissADME, and the potential targets of which were acquired from SwissTargetPrediction. Depression-related targets were collected from GeneCards. The intersection between compound-related targets and depression-related targets were screened out, and the overlapped targets were further performed protein-protein interaction, biological functional and pathway enrichment analysis. Finally, networks of Si-Ni-San against depression were constructed and visualized by Cytoscape.

Results

One hundred nineteen compounds in Si-Ni-San were determined, of which 24 bioactive compounds were obtained. Then, 137 overlapped targets of Si-Ni-San against depression were collected. AKT1, PIK3R1, PIK3CA, mTOR, MAPK1 and MAPK8 were the key targets. Furthermore, PI3K-Akt signalling pathway, serotonergic synapse, MAPK signalling pathway and neurotrophin signalling pathway were involved in the antidepressant mechanism of Si-Ni-San. It showed that components like sinensetin, hesperetin, liquiritigenin, naringenin, quercetin, albiflorin and paeoniflorin were the mainly key active compounds for the antidepressant effect of Si-Ni-San.

Conclusions

This study demonstrated the key components, key targets and potential pharmacological mechanisms of Si-Ni-San against depression. These results indicate that Si-Ni-San is a promising therapeutic approach for treatment of depression, and may provide evidence for the research and development of drugs for treating depression.

Pomegranate (Punica granatum L.) and its phytochemicals as anxiolytic; an underreported effect with therapeutic potential: A systematic review

Anxiety is a mental disorder characterized by excessive concern about possible future threats that, if prolonged, becomes a pathology that must be controlled through psychotherapy and medication. Currently, the pharmacological treatment for anxiety involves the use of antidepressants and benzodiazepines; however, these treatments often come with adverse effects. Thus, there is a need to seek natural compounds that can help alleviate anxiety and reduce these side effects. On the other hand, pomegranate (PG) fruit is known to have important health benefits, which have been compiled in several reviews. However, its anxiolytic effect has not been thoroughly studied, and clinical research on this topic is lacking. The aim of this work was to conduct a systematic review of studies exploring the anxiolytic-like effect of PG and its phytochemicals. Databases such as Pubmed, ScienceDirect, Springer link, Google scholar, Worldwide science, and Web of science were searched for articles using predetermined terms. Inclusion criteria were established, and original articles that met these criteria were selected. The data collected included information on PG part and variety, species, sample size, anxiety model, dose, route and time of administration, reference drug, main results, and the mechanisms of action. Fifty-nine studies were found that reported the anxiolytic-like effect of PG and its phytochemicals such as anthocyanins, flavonoids, tannins, organic acids, and xanthonoids. The literature suggests that the mechanisms of action behind this effect involved the inhibition of the GABAergic receptor, NMDA, CaMKII/CREB pathway; the reduction of oxidative stress, inhibiting TLR4 and nNOS; modulation of cytokines and the expression of NFkB, GAD67, and iNOS, as well as the activation of Nrf2 and AMPK. PG and some of its phytochemicals could be considered as a novel alternative for the treatment of pathological anxiety. This review is the first to document the anxiolytic-like effect of PG.

Prevention of neurotoxicity and cognitive impairment induced by zinc nanoparticles by oral administration of saffron extract

The accumulation of relatively higher dose of zinc oxide nanoparticles in brain was reported to produce neurotoxicity. Indeed, nanoparticles have a high ability to penetrate biological membranes and be uptaken by cells, which may cause cell disorders and physiological dysfunctions. The aim of the current study was to evaluate, whether oral administration of saffron extract, in rats, can protect from neurotoxicity and behavioural disturbances induced by chronic administration of ZnO-NPs. Daily oral administration of ZnO-NPs was performed for 21 consecutive days to induce oxidative stress-like situation. Then after the saffron extract was concomitantly administrated in several rat groups to overcome the nanotoxicological effect induced by ZnO-NPs. In the frontal cortex, the hippocampus and the cerebellum, ZnO-NPs induced a H2 O2 -oxydative stress-like effect reflected in reduced enzymatic activities of catalase, superoxide dismutase and glutathione S-transferase, and decreased acetylcholinesterase activity. In addition, increased levels of proinflammatory interleukins IL-6 and IL-1-⍺ occurred in the hippocampus, reveal the existence of brain inflammation. The concomitant administration of saffron extract to animals exposed to ZnO-NPs prevented the enhanced anxiety-related to the behaviour in the elevated plus-maze test, the open field test and preserved spatial learning abilities in the Morris water maze. Moreover, animals exposed to ZnO-NPs and saffron showed abnormal activity of several antioxidant enzymes as well as acetylcholinesterase activity, an effect that may underly the preserved anxiety-like behaviour and spatial learning abilities observed in these animals. Saffron extract has a potential beneficial therapeutic effect: antioxidant, anti-inflammatory and neuroprotective agent.

Analysis of cell-specific transcriptional responses in human colon tissue using CIBERSORTx

Diet is an important determinant of overall health, and has been linked to the risk of various cancers. To understand the mechanisms involved, transcriptomic responses from human intervention studies are very informative. However, gene expression analysis of human biopsy material only represents the average profile of a mixture of cell types that can mask more subtle, but relevant cell-specific changes. Here, we use the CIBERSORTx algorithm to generate single-cell gene expression from human multicellular colon tissue. We applied the CIBERSORTx to microarray data from the PHYTOME study, which investigated the effects of different types of meat on transcriptional and biomarker changes relevant to colorectal cancer (CRC) risk. First, we used single-cell mRNA sequencing data from healthy colon tissue to generate a novel signature matrix in CIBERSORTx, then we determined the proportions and gene expression of each separate cell type. After comparison, cell proportion analysis showed a continuous upward trend in the abundance of goblet cells and stem cells, and a continuous downward trend in transit amplifying cells after the addition of phytochemicals in red meat products. The dietary intervention influenced the expression of genes involved in the growth and division of stem cells, the metabolism and detoxification of enterocytes, the translation and glycosylation of goblet cells, and the inflammatory response of innate lymphoid cells. These results show that our approach offers novel insights into the heterogeneous gene expression responses of different cell types in colon tissue during a dietary intervention.

Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging

A physiological level of oxygen/nitrogen free radicals and non-radical reactive species (collectively known as ROS/RNS) is termed oxidative eustress or "good stress" and is characterized by low to mild levels of oxidants involved in the regulation of various biochemical transformations such as carboxylation, hydroxylation, peroxidation, or modulation of signal transduction pathways such as Nuclear factor-κB (NF-κB), Mitogen-activated protein kinase (MAPK) cascade, phosphoinositide-3-kinase, nuclear factor erythroid 2-related factor 2 (Nrf2) and other processes. Increased levels of ROS/RNS, generated from both endogenous (mitochondria, NADPH oxidases) and/or exogenous sources (radiation, certain drugs, foods, cigarette smoking, pollution) result in a harmful condition termed oxidative stress ("bad stress"). Although it is widely accepted, that many chronic diseases are multifactorial in origin, they share oxidative stress as a common denominator. Here we review the importance of oxidative stress and the mechanisms through which oxidative stress contributes to the pathological states of an organism. Attention is focused on the chemistry of ROS and RNS (e.g. superoxide radical, hydrogen peroxide, hydroxyl radicals, peroxyl radicals, nitric oxide, peroxynitrite), and their role in oxidative damage of DNA, proteins, and membrane lipids. Quantitative and qualitative assessment of oxidative stress biomarkers is also discussed. Oxidative stress contributes to the pathology of cancer, cardiovascular diseases, diabetes, neurological disorders (Alzheimer's and Parkinson's diseases, Down syndrome), psychiatric diseases (depression, schizophrenia, bipolar disorder), renal disease, lung disease (chronic pulmonary obstruction, lung cancer), and aging. The concerted action of antioxidants to ameliorate the harmful effect of oxidative stress is achieved by antioxidant enzymes (Superoxide dismutases-SODs, catalase, glutathione peroxidase-GPx), and small molecular weight antioxidants (vitamins C and E, flavonoids, carotenoids, melatonin, ergothioneine, and others). Perhaps one of the most effective low molecular weight antioxidants is vitamin E, the first line of defense against the peroxidation of lipids. A promising approach appears to be the use of certain antioxidants (e.g. flavonoids), showing weak prooxidant properties that may boost cellular antioxidant systems and thus act as preventive anticancer agents. Redox metal-based enzyme mimetic compounds as potential pharmaceutical interventions and sirtuins as promising therapeutic targets for age-related diseases and anti-aging strategies are discussed.

Quercetin mitigates depression-like behavior via the suppression of neuroinflammation and oxidative damage in corticosterone-induced mice

Depression is a clinically common and easily overlooked mental disease. Quercetin is a flavonoid compound, which has anti-inflammatory and antioxidant roles. Previous reports presented the anti-depressant role of quercetin. Nevertheless, the latent mechanism of the anti-depressant function of quercetin is blurry. This research aimed to probe its effects on corticosterone (CORT)-induced depression-like behaviors and explore the underlying mechanism. A depression model was established by subcutaneous injection of CORT (20 mg/kg). Thereafter, CORT-treated mice were given 40 mg/kg and 80 mg/kg of quercetin by gavage. This study found that quercetin mitigated depression-like behaviors, as evidenced by increased the number of line crossings, swimming time, and time spent in open arm and reduced thigmotaxis time in CORT-challenged mice in open field test and decreased immobility time as well as the swimming and climbing time in forced swim test and increased number of head dips, time spent and entries in open arm elevated plus maze test. Also, quercetin exerted anti-inflammatory and anti-oxidation effects in hippocampus and prefrontal cortex of CORT-induced mice. Additionally, quercetin alleviated the pathological injury of the liver tissue and weakened alkaline phosphatase (ALP) and alanine aminotransferase (ALT) concentrations of the serum in CORT-induced mice. Quercetin also suppressed Caspase-3 content but advanced vascular endothelial growth factor (VEGF) and brain derived neurotrophic factor (BDNF) contents in hippocampus of CORT-treated mice. Based on these results, quercetin mitigated CORT-induced depression-like behaviors, and the mechanism was partly related to the repression of neuroinflammation and oxidative damage.

Mitigation of behavioral deficits and cognitive impairment by antioxidant and neuromodulatory potential of Mukia madrespatana in D-galactose treated rats

Plants and their parts have been extensively used for the therapeutic purposes such as aging due to their powerful antioxidative belongings. Presently, we intended to examine the consequence of fruit peel of Mukia madrespatana (M.M) on D-galactose (D-Gal) persuaded anxiety and/or depression profile, cognition and serotonin metabolism in rats. Animals were divided in to 4 groups (n = 6). (i) Water treated (ii) D-Gal treated (iii) M.M. treated (iv) D-Gal + M.M. treated. All the animals received their respective treatment for 4 weeks. D-Gal and M.M. fruit peel were given to animals with oral gavage with doses 300 mg/ml/kg/day and 2 g/kg/day respectively. After 4 weeks' behavioral analysis performed to evaluate anxiety and depression profile, cognitive function of animals. After that animals were sacrificed and whole brain removed for biochemical (redox status, degradative enzyme of acetylcholine), and neurochemical (serotonin metabolism) analysis. Results showed that administration of M.M. inhibited D-Gal-instigated anxious and depressive behaviors and improved cognition. Treatment of M.M. decreased MDA levels, AChE activity and increased antioxidant enzyme activity in D-Gal administered and control rats. Enhanced serotonin metabolism also decreased by M.M. in control and D-Gal administered rats. In conclusion, M.M. fruit peel has powerful antioxidative and neuromodulatory properties and due to this effect, it may be a good source of mitigation/treatment for aging induced behavioral and cognitive impairment.

Effects of quercetin supplementation on endothelial dysfunction biomarkers and depression in post-myocardial infarction patients: A double-blind, placebo-controlled, randomized clinical trial

BACKGROUND

Endothelial dysfunction and depression are highly prevalent in patients who have experienced a myocardial infarction (MI). Epidemiological studies have pointed out that a diet rich in flavonoids, e.g., quercetin, can prevent the development of these biological phenomena. Therefore, we aimed to investigate the effects of quercetin supplementation on the levels of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) and on depression in post-MI subjects.

METHODS

Eighty-eight post-MI patients who had experienced their first MI (body mass index ≤35 kg/m², age 30-65 years) were recruited from the Rasool-e-Akram and Afshar Hospitals, Iran, and included in this randomized, placebo-controlled, double-blind parallel study. The participants were randomly assigned to receive a daily dose of 500 mg quercetin (n = 44) or placebo (n = 44) for 8 weeks. Serum concentrations of ICAM-1 and VCAM-1 were quantified by ELISA and depression levels were assessed using the Beck's Depression Inventory (BDI-II) questionnaire at baseline and at 8-week follow-up.

RESULTS

Seventy-six participants completed the study, but the intention-to-treat (ITT) analysis was conducted for all 88 participants who were randomized into the intervention groups. No significant changes in serum concentrations of ICAM-1 or VCAM-1 (P = 0.21 and P = 0.80, respectively) were observed after 8 weeks of quercetin supplementation versus placebo. In addition, depression levels did not differ significantly between the quercetin and placebo groups.

CONCLUSION

Our findings demonstrated that in post-MI patients, daily supplementation with quercetin (500 mg/day) for 8 weeks did not affect endothelial dysfunction biomarkers and depression levels. This trial was registered at IRCT.ir as IRCT20190428043405N1.

Coriandrum sativum and Its Utility in Psychiatric Disorders

The negative impact on worldwide social well-being by the increasing rate of psychiatric diseases has led to a continuous new drug search. Even though the current therapeutic options exert their activity on multiple neurological targets, these have various adverse effects, causing treatment abandonment. Recent research has shown that Coriandrum sativum offers a rich source of metabolites, mainly terpenes and flavonoids, as useful agents against central nervous system disorders, with remarkable in vitro and in vivo activities on models related to these pathologies. Furthermore, studies have revealed that some compounds exhibit a chemical interaction with γ-aminobutyric acid, 5-hydroxytryptamine, and N-methyl-D-aspartate receptors, which are key components in the pathophysiology associated with psychiatric and neurological diseases. The current clinical evaluations of standardized extracts of C. sativum are scarce; however, one or more of its compounds represents an area of opportunity to test the efficacy of the plant as an anxiolytic, antidepressant, antiepileptic, or sleep enhancer. For this, the aim of the review was based on the pharmacological activities offered by the compounds identified and isolated from coriander and the processes involved in achieving their effect. In addition, lines of technological research, like molecular docking and nanoparticles, are proposed for the future development of phytomedicines, based on the bioactive molecules of C. sativum, for the treatment of psychiatric and neurological disorders addressed in the present study.

Chimaphila umbellata; a biotechnological perspective on the coming-of-age prince's pine

Chimaphila umbellata has been studied for almost two centuries now, with the first paper exploring the phytochemistry of the plant published in 1860. Almost all contemporary studies focus on the biotechnological advances of C. umbellata including its utilization as a natural alternative in the cosmetic, food, biofuel, and healthcare industry, with a special focus on its therapeutic uses. This literature review critically investigates the significance and applications of secondary metabolites extracted from the plant and presses on the biotechnological approaches to improve its utilization. C. umbellata is home to many industrially and medicinally important phytochemicals, the majority of which belong to phenolics, sterols, and triterpenoids. Other important compounds include 5-hydroxymethylfurfural, isohomoarbutin, and methyl salicylate (the only essential oil of the plant). Chimaphilin is the characteristic phytochemical of the plant. This review focuses on the phytochemistry of C. umbellata and digs into their chemical structures and attributes. It further discusses the challenges of working with C. umbellata including its alarming conservation status, problems with in-vitro cultivation, and research and development issues. This review concludes with recommendations based on biotechnology, bioinformatics, and their crucial interface.

Insights into the potential benefits of triphala polyphenols toward the promotion of resilience against stress-induced depression and cognitive impairment

In response to environmental challenges, stress is a common reaction, but dysregulation of the stress response can lead to neuropsychiatric disorders, including depression and cognitive impairment. Particularly, there is ample evidence that overexposure to mental stress can have lasting detrimental consequences for psychological health, cognitive function, and ultimately well-being. In fact, some individuals are resilient to the same stressor. A major benefit of enhancing stress resilience in at-risk groups is that it may help prevent the onset of stress-induced mental health problems. A potential therapeutic strategy for maintaining a healthy life is to address stress-induced health problems with botanicals or dietary supplements such as polyphenols. Triphala, also known as Zhe Busong decoction in Tibetan, is a well-recognized Ayurvedic polyherbal medicine comprising dried fruits from three different plant species. As a promising food-sourced phytotherapy, triphala polyphenols have been used throughout history to treat a variety of medical conditions, including brain health maintenance. Nevertheless, a comprehensive review is still lacking. Here, the primary objective of this review article is to provide an overview of the classification, safety, and pharmacokinetics of triphala polyphenols, as well as recommendations for the development of triphala polyphenols as a novel therapeutic strategy for promoting resilience in susceptible individuals. Additionally, we summarize recent advances demonstrating that triphala polyphenols are beneficial to cognitive and psychological resilience by regulating 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor (BDNF) receptors, gut microbiota, and antioxidant-related signaling pathways. Overall, scientific exploration of triphala polyphenols is warranted to understand their therapeutic efficacy. In addition to providing novel insights into the mechanisms of triphala polyphenols for promoting stress resilience, blood brain barrier (BBB) permeability and systemic bioavailability of triphala polyphenols also need to be improved by the research community. Moreover, well-designed clinical trials are needed to increase the scientific validity of triphala polyphenols' beneficial effects for preventing and treating cognitive impairment and psychological dysfunction.

Quercetin abrogates lipopolysaccharide-induced depressive-like symptoms by inhibiting neuroinflammation via microglial NLRP3/NFκB/iNOS signaling pathway

BACKGROUND

Major depressive disorder is a serious psychiatric illness having serious damaging effect on the quality of life of suffers. Quercetin is a plant flavonoid, mostly used as a constituent in dietary products. This study evaluated antidepressant effect of quercetin on lipopolysaccharide (LPS)-induced depression in rats.

MATERIALS AND METHODS

Twenty-one male rats were randomly assigned into three groups (n= 7): group 1 (vehicle only), group 2 (quercetin), group 3 (LPS). Rats were treated with vehicle (10mL/kg, p.o.) or quercetin (50mg/kg, p.o.) for seven days. Sixty minutes after treatment on day seven, all animals were injected with LPS (0.83mg/kg, i.p.) except group 1 (vehicle only). Twenty-four hours after LPS injection, animals were assessed for depressive symptoms using forced swim, sucrose splash and open field tests. Animals were sacrificed; brain samples collected for bioassay of pro-inflammatory mediators, TNF-α, IL-6 and IL-17 were measured using enzyme-linked immunosorbent assay (ELISA) while expressions of NF-κB, inflammasomes, microglia and iNOS were quantified by immunohistochemistry.

RESULTS

The LPS significantly (p<0.05) decreased mobility of rats in FST and decreased sucrose preference, which is indicative of depressive-like behaviours. These behaviours were significantly (p<0.05) attenuated by quercetin compared to control (vehicle only). Following LPS exposure, the expressions of inflammasomes, NF-κB, iNOS, proinflammatory cytokines and microglia positive cells in the hippocampus and prefrontal cortex were significantly (p<0.05) elevated. All these were attenuated by pretreating animals with quercetin.

CONCLUSION

Quercetin exhibit antidepressant-like property, which may be related to inhibition of neuroinflammatory signaling pathways.

SAG, a sonic hedgehog signaling agonist, alleviates anxiety behavior in high-fat diet-fed mice

Anxiety is a prevalent and disabling psychiatric disorder. Mitochondrial dysfunction due to the high-fat diet (HFD) was regarded as a risk factor in the pathogenesis of anxiety. The Sonic hedgehog (SHH) pathway was known to improve mitochondrial dysfunction through antioxidant and anti-apoptotic effects on some neurological diseases. Nonetheless, its effect on anxiety has not been well studied. In this study, we aimed to explore whether SHH signaling pathway plays a protective role in anxiety by regulating mitochondrial homeostasis. SAG, a typical SHH signaling agonist, was administered intraperitoneally in HFD-fed mice. HFD-induced anxiety-like behavior in mice was confirmed using the open field and elevated plus maze tests. Immunofluorescence staining and Western blotting assays showed that the SHH signaling was downregulated in the prefrontal cortex neurons from HFD-fed mice. Electron microscopy results showed the mitochondria in the prefrontal cortex of HFD-fed mice were fragmented, which appeared small and spherical, and the area, perimeter and circularity of mitochondria were decreased. Mitofusin2 (Mfn2) and dynamin-related protein 1 (Drp1) were the key proteins involved in mitochondrial division and fusion. SAG treatment could rectify the imbalanced expression of Mfn2 and Drp1 in the prefrontal cortex of the HFD-fed mice, and alleviate the mitochondrial fragmentation. Furthermore, SAG decreased anxiety-like behavior in the HFD-fed mice. These findings suggested that SHH signal was neuroprotective in obesity and SAG relieved anxiety-like behavior through reducing mitochondrial fragmentation.

Anxiolytic and Antidepressant Potential of Methanolic Extract of Neurada procumbens Linn. in Mice

Neurada procumbens Linn. possesses a wide range of phytochemical and bioactive entities such as flavonoids and polyphenols that decrease the oxidative stress and enhance synaptic plasticity, resulting in accelerated healing processes. Almost all parts of the plant have been used in the traditional system of medicine for various disorders including its use as an anticonvulsant, sexual tonic, and anti-rheumatic agent. This study is designed to evaluate the anxiolytic and antidepressant activities of the methanolic crude extract of N. procumbens (Np.Cr) based on its use in traditional medicine and presence of the phytochemical constituents. Aqueous methanolic extract of Np.Cr was prepared under reduced pressure using rotary evaporator, and different chemical constituents were identified by phytochemical screening. Light/dark exploration, elevated plus maze (EPM), and hole board tests were used to assess the anxiolytic activity, while forced swim and tail suspension tests were used to assess the antidepressant potential of the crude extract. Treatment groups treated individually with 3 different doses; i.e., 50, 100, and 200 mg/kg of Np.Cr, showed a dose-dependent increase in time spent in light compartment and in open arms as well as increased number of head poking by the experimental animals. Np.Cr showed significant antidepressant potential (P < .05) as evident from marked decrease in behavioral despair. Findings of the present study assure that N. procumbens possess significant anxiolytic and antidepressant potential with the demands of further investigations to identify the active compound(s) responsible for these pharmacological effects.

Research progress of traditional Chinese medicine compound "Xiaochaihu Decoction" in the treatment of depression

Depression is a common psychiatric disorder under the category of depression syndrome in Traditional Chinese Medicine (TCM) theory. Meanwhile, Xiaochaihu Decoction is a classical TCM formulation regulating Qi, resolving and dissipating stagnation. Clinically, the formulation has long been adopted to treat Shaoyang stagnation syndrome for depression syndrome. In this review, potential targets of action and the corresponding pathways of Xiaochaihu Decoction are explored for depression treatment via network pharmacology. The article also systematically summarizes the active components and pharmacological mechanisms of seven Chinese herbal medicine components in Xiaochaihu Decoction and guides the future study direction of Xiaochaihu Decoction, which may serve a promising treatment for depression.

Anxiety and Metabolic Disorders: The Role of Botanicals

Anxiety and anxiety-related disorders are becoming more evident every day, affecting an increasing number of people around the world. Metabolic disorders are often associated with anxiety. Furthermore, anxiety branches into metabolic disorders by playing multiple roles as a cofactor, symptom, and comorbidity. Taken together, these considerations open the possibility of integrating the therapy of metabolic disorders with specific drugs for anxiety control. However, anxiolytic compounds often cause disabling effects in patients. The main goal could be to combine therapeutic protocols with compounds capable of reducing side effects while performing multiple beneficial effects. In this article we propose a group of bioactive ingredients called botanicals as a healthy supplement for the treatment of metabolic disorders related to anxiety.

Neuroprotective Potentials of Flavonoids: Experimental Studies and Mechanisms of Action

Neurological and neurodegenerative diseases, particularly those related to aging, are on the rise, but drug therapies are rarely curative. Functional disorders and the organic degeneration of nervous tissue often have complex causes, in which phenomena of oxidative stress, inflammation and cytotoxicity are intertwined. For these reasons, the search for natural substances that can slow down or counteract these pathologies has increased rapidly over the last two decades. In this paper, studies on the neuroprotective effects of flavonoids (especially the two most widely used, hesperidin and quercetin) on animal models of depression, neurotoxicity, Alzheimer's disease (AD) and Parkinson's disease are reviewed. The literature on these topics amounts to a few hundred publications on in vitro and in vivo models (notably in rodents) and provides us with a very detailed picture of the action mechanisms and targets of these substances. These include the decrease in enzymes that produce reactive oxygen and ferroptosis, the inhibition of mono-amine oxidases, the stimulation of the Nrf2/ARE system, the induction of brain-derived neurotrophic factor production and, in the case of AD, the prevention of amyloid-beta aggregation. The inhibition of neuroinflammatory processes has been documented as a decrease in cytokine formation (mainly TNF-alpha and IL-1beta) by microglia and astrocytes, by modulating a number of regulatory proteins such as Nf-kB and NLRP3/inflammasome. Although clinical trials on humans are still scarce, preclinical studies allow us to consider hesperidin, quercetin, and other flavonoids as very interesting and safe dietary molecules to be further investigated as complementary treatments in order to prevent neurodegenerative diseases or to moderate their deleterious effects.

Anti-Inflammatory, Antioxidant, and Neuroprotective Effects of Polyphenols-Polyphenols as an Element of Diet Therapy in Depressive Disorders

Depressive disorders can affect up to 350 million people worldwide, and in developed countries, the percentage of patients with depressive disorders may be as high as 10%. During depression, activation of pro-inflammatory pathways, mitochondrial dysfunction, increased markers of oxidative stress, and a reduction in the antioxidant effectiveness of the body are observed. It is estimated that approximately 30% of depressed patients do not respond to traditional pharmacological treatments. However, more and more attention is being paid to the influence of active ingredients in food on the course and risk of neurological disorders, including depression. The possibility of using foods containing polyphenols as an element of diet therapy in depression was analyzed in the review. The possibility of whether the consumption of products such as polyphenols could alleviate the course of depression or prevent the progression of it was also considered. Results from preclinical studies demonstrate the potential of phenolic compounds have the potential to reduce depressive behaviors by regulating factors related to oxidative stress, neuroinflammation, and modulation of the intestinal microbiota.

Vitiligo and Mental Health: Natural Compounds' Usefulness

Vitiligo is an autoimmune dermatosis frequently associated with other comorbidities, such as mental health disorders. It is unclear if vitiligo triggers mental disorders or if mental disorders trigger vitiligo, but each one affects and worsen the other, if present at the same time. Both mental health disorders and vitiligo present a multifactorial pathogenesis and often require prolonged periods of therapy, sometimes with poor results. Given the possible link of common pathogenetic factors and the need of integrated therapies, the aim of this review is to look at natural compounds as possible supplements for both conditions. The results yielded show a possible role of these supplements in ameliorating both conditions, thus helping these patients to achieve a better quality of life and reduce the need for prolonged therapies. The limitations regarding the relative lack of in vivo studies, and the increasing need to lighten the burden of these chronic diseases, suggests that it is mandatory to proceed with further trials.

Natural Phytochemicals for the Treatment of Major Depressive Disorder: A Mini-Review of Pre- and Clinical Studies

Major Depressive Disorder (MDD) is a common mental illness that causes significant disability and declining quality of life. An overlap of multiple factors can be involved in the pathophysiology of this mood disorder, including increased inflammation and oxidative stress, change in neurotransmitters, decreased brain-derived neurotrophic factor (BDNF), activation of the hypothalamicpituitary- adrenal (HPA) axis, and changes in the microbiota-gut-brain axis. Although the classic treatment for MDD is safe, it is far from ideal, with delay to start the best clinic, side effects, and a large number of non-responses or partial-responses. Therefore, other alternatives are being studied to improve depressive symptoms, and, among them, the role of phytochemicals in food stands out. This mini-review will discuss the main phytochemicals present in foods with clinical and preclinical studies showing benefits for MDD treatment. In addition, the main mechanisms of action that are being proposed for each of these compounds will be addressed.

Free-L-Cysteine improves corticosterone-induced behavioral deficits, oxidative stress and neurotransmission in rats

L-Cysteine (L-Cys) is a semi-essential amino acid. It serves as a substrate for enzyme cystathionine-β-synthase in the central nervous system (CNS). L-Cys showed various antioxidant characteristics. Though, studies on the effect of free L-Cys administration to evaluate the CNS functioning is very limited. Therefore, we assessed the effects of L-Cys on corticosterone (CORT) induced oxidative stress, behavioral deficits and memory impairment in male rats. L-Cys (150 mg/kg/ml) administered to vehicle and CORT (20 mg/kg/ml) treated rats orally for 28 days. Behavioral activities were conducted after treatment period. Subsequently, rats were sacrificed, blood and brain were removed. Hippocampus was isolated from brain and then hippocampus and plasma were collected for oxidative, biochemical and neurochemical analysis. Results showed that repeated treatment of L-Cys produced antidepressant, anxiolytic and memory-improving effects which may be ascribed to the enhanced antioxidant profile, normalized cholinergic, serotonergic neurotransmission in brain (hippocampus) following CORT administration. Increased plasma CORT by CORT administration was also normalized by L-Cys. The current study concluded that administration of free L-Cys improved the behavioral, biochemical, neurochemical and redox status of CNS. Hence, L-Cys could be protective therapeutic modulator against stress induced neurological ailments.

Reversal of oxidative stress, cytokine toxicity and DNA fragmentation by quercetin in dizocilpine-induced animal model of Schizophrenia

Quercetin, a polyphenolic compound found in a variety of plant products possesses various biological activities and beneficial effects on human health. Schizophrenia (SZ) is one of the neuropsychiatric disorders in human beings with rapid mortality and intense morbidity which can be treated with antipsychotics, but these commercial drugs exert adverse effects and have less efficacy to treat the full spectrum of SZ. The present study was conducted to evaluate neuroprotective effects of quercetin in the preventive and therapeutic treatment of SZ. Quercetin was administered as pre- and post-regimens at the dose of 50 mg/kg in dizocilpine-induced SZ rat model for two weeks. Rats were then subjected for the assessment of different behaviors followed by biochemical, neurochemical, and inflammatory marker analyses. The present findings revealed that quercetin significantly reverses the effects of dizocilpine-induced psychosis-like symptoms in all behavioral assessments as well as it also combats oxidative stress. This flavonoid also regulates dopaminergic, serotonergic, and glutamatergic neurotransmission. A profound effect on inflammatory cytokines and decreased %DNA fragmentation was also observed following the administration of quercetin. The findings suggest that quercetin can be considered as a preventive as well as therapeutic strategy to attenuate oxidative stress and cytokine toxicity, regulate neurotransmission, and prevent enhanced DNA fragmentation that can lead to the amelioration of psychosis-like symptoms in SZ.

Antidepressant Active Components of Bupleurum chinense DC-Paeonia lactiflora Pall Herb Pair: Pharmacological Mechanisms

Depression is a serious psychological disorder with a rapidly increasing incidence in recent years. Clinically, selective serotonin reuptake inhibitors are the main therapy. These drugs, have serious adverse reactions, however. Traditional Chinese medicine has the characteristics of multiple components, targets, and pathways, which has huge potential advantages for the treatment of depression. The antidepressant potential of the herbal combination of Bupleurum chinense DC (Chaihu) and Paeonia lactiflora Pall (Baishao) has been extensively studied previously. In this review, we summarized the antidepressant active components and mechanism of Chaihu-Baishao herb pair. We found that it works mainly through relieving oxidative stress, regulating HPA axis, and protecting neurons. Nevertheless, current research of this combined preparation still faces many challenges. On one hand, most of the current studies only stay at the level of animal models, lacking of sufficient clinical double-blind controlled trials for further verification. In addition, studies on the synergistic effect between different targets and signaling pathways are scarce. On the other hand, this preparation has numerous defects such as poor stability, low solubility, and difficulty in crossing the blood-brain barrier.

Anxiolytic-like Effect of Quercetin Possibly through GABA Receptor Interaction Pathway: In Vivo and In Silico Studies

Scientific evidence suggests that quercetin (QUR) has anxiolytic-like effects in experimental animals. However, the mechanism of action responsible for its anxiolytic-like effects is yet to be discovered. The goal of this research is to assess QUR's anxiolytic effects in mouse models to explicate the possible mechanism of action. After acute intraperitoneal (i.p.) treatment with QUR at a dose of 50 mg/kg (i.p.), behavioral models of open-field, hole board, swing box, and light-dark tests were performed. QUR was combined with a GABAergic agonist (diazepam) and/or antagonist (flumazenil) group. Furthermore, in silico analysis was also conducted to observe the interaction of QUR and GABA (α5), GABA (β1), and GABA (β2) receptors. In the experimental animal model, QUR had an anxiolytic-like effect. QUR, when combined with diazepam (2 mg/kg, i.p.), drastically potentiated an anxiolytic effect of diazepam. QUR is a more highly competitive ligand for the benzodiazepine recognition site that can displace flumazenil (2.5 mg/kg, i.p.). In all the test models, QUR acted similar to diazepam, with enhanced effects of the standard anxiolytic drug, which were reversed by pre-treatment with flumazenil. QUR showed the best interaction with the GABA (α5) receptor compared to the GABA (β1) and GABA (β2) receptors. In conclusion, QUR may exert an anxiolytic-like effect on mice, probably through the GABA-receptor-interacting pathway.

Protective effect of Grewia asiatica leaves extract in animal models of epilepsy and anxiety

Grewia asiatica Linn. is a well-known plant for its nutritional and therapeutic attributes. It has been mentioned in ancient Indian literature as Rasayana due to its stimulant and tonic effects. Thus, present investigation was carried out to evaluate the antiepileptic and anxiolytic action of G. asiatica Linn. leaves using animal models. Methanol extract at dose levels of 100 and 200 mg/kg was capable of providing protection against both pentylenetetrazole and maximal electroshock induced seizures in mice. Extract also showed significant anxiolytic activity in elevated plus maze, light/dark box and mirror chamber mice models at same dose levels. Results of this study indicated that the methanol extract of leaves of G. asiatica plant possess significant antiepileptic and anxiolytic effect.

Sakuranetin exerts anticonvulsant effect in bicuculline-induced seizures

Epilepsy is a chronic neurological disorder characterized by an abnormal, spontaneous, and synchronized neuronal hyperactivity. Therapeutic approaches for controlling epileptic seizures are associated with pharmacoresistance and side effects burden. Previous studies reported that different natural products may have neuroprotector effects. Sakuranetin (SAK) is a flavanone with antiparasitic, anti-inflammatory, antimutagenic, antiallergic, and antioxidant activity. In the present work, the effect of SAK on seizures in a model of status epilepticus induced by bicuculline (BIC) in mice was evaluated. Male Swiss mice received an intracerebroventricular injection (i.c.v.) of SAK (1, 10, or 20 mg/kg-SAK1, SAK10, or SAK20). Firstly, animals were evaluated in the open field (OF; 20 min), afterwards in the elevated plus maze (EPM) test (5 min). Next, 30 min prior the administration of BIC (1 mg/kg), mice received an injection of SAK (1 or 10 mg/kg, i.c.v.) and were observed in the OF (20 min) for seizures assessment. After behavioral procedures, immunohistochemical analysis of c-Fos was performed. Our main results showed that the lowest doses of SAK (1 and 10 mg/kg) increased the total distance traveled in the OF, moreover protected against seizures and death on the BIC-induced seizures model. Furthermore, SAK treatment reduced neuronal activity on the dentate gyrus of the BIC-treated animals. Taken together, our results suggest an anticonvulsant effect of SAK, which could be used for the development of anticonvulsants based on natural products from herbal source.

Potential Therapeutic Benefits of Honey in Neurological Disorders: The Role of Polyphenols

Honey is the principal premier product of beekeeping familiar to Homo for centuries. In every geological era and culture, evidence can be traced to the potential usefulness of honey in several ailments. With the advent of recent scientific approaches, honey has been proclaimed as a potent complementary and alternative medicine for the management and treatment of several maladies including various neurological disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and multiple sclerosis, etc. In the literature archive, oxidative stress and the deprivation of antioxidants are believed to be the paramount cause of many of these neuropathies. Since different types of honey are abundant with certain antioxidants, primarily in the form of diverse polyphenols, honey is undoubtedly a strong pharmaceutic candidate against multiple neurological diseases. In this review, we have indexed and comprehended the involved mechanisms of various constituent polyphenols including different phenolic acids, flavonoids, and other phytochemicals that manifest multiple antioxidant effects in various neurological disorders. All these mechanistic interpretations of the nutritious components of honey explain and justify the potential recommendation of sweet nectar in ameliorating the burden of neurological disorders that have significantly increased across the world in the last few decades.

Evidence and Characteristics of Traditional Chinese Medicine for Coronary Heart Disease Patients With Anxiety or Depression: A Meta-Analysis and Systematic Review

Aims: The objective of this study was to assess the efficacy and potential mechanisms of Chinese herbal medicine (CHM) for treating coronary heart disease (CHD) patients with anxiety or depression.

Methods: A systematic literature search was performed. Screening studies, extracting data, and assessing article quality were carried out independently by two researchers. The active ingredients of CHM for the treatment of CHD with anxiety or depression were analyzed by the network pharmacology, and the main potential mechanisms were summarized by the database of Web of Science.

Results: A total of 32 studies were included. The results showed that compared with the blank control groups, CHM was more beneficial in treating anxiety or depression in patients with CHD [anxiety: OR = 3.22, 95% CI (1.94, 5.35), p &lt; 0.00001, I2 = 0%; depression: OR = 3.27, 95% CI (1.67, 6.40), p = 0.0005, I2 = 0%], and the efficacy of CHM was not inferior to that of Western medicine (WM) [anxiety: OR = 1.58, 95%CI (0.39, 6.35), p = 0.52, I2 = 67%; depression: OR = 1.97, 95%CI (0.73, 5.28), p = 0.18, I2 = 33%,]. Additionally, CHM also showed a significant advantage in improving angina stability (AS) in CHD patients with anxiety or depression compared with blank groups [anxiety: SMD = 0.55, 95%CI (0.32, 0.79), p &lt; 0.00001, I2 = 0%; depression: p = 0.004] and WM groups [anxiety: SMD = 1.14, 95%CI (0.80, 1.47), p &lt; 0.00001, I2 = 0%; depression: SMD = 12.15, 95%CI (6.07, 18.23), p &lt; 0.0001, I2 = 0%]. Angina frequency (AF) and electrocardiogram (ECG) analysis after using CHM demonstrated similar trends. Based on the network pharmacology, quercetin, kaempferol, luteolin, beta-sitosterol, puerarin, stigmasterol, isorhamnetin, baicalein, tanshinone IIa, and nobiletin were most closely and simultaneously related to the pathological targets of CHD, anxiety, and depression. The main underlying mechanisms might involve anti-damage/apoptosis, anti-inflammation, antioxidative stress, and maintaining neurotransmitter homeostasis.

Conclusion: CHM exhibited an obvious efficacy in treating CHD patients with anxiety or depression, especially for improving the symptom of angina pectoris. The most active compounds of CHM could simultaneously act on the pathological targets of CHD, anxiety, and depression. Multiple effective components and multiple targets were the advantages of CHM compared with WM.

The Role of Natural Products in Treatment of Depressive Disorder

Depressive disorder is one of the most common psychiatric syndromes that, if left untreated, can cause many disturbances in a person's life. Numerous factors are involved in depression, including inflammation, brain-derived neurotrophic factor (BDNF), GABAergic system, hypothalamic- pituitary-adrenal (HPA) Axis, monoamine neurotransmitters (serotonin (5-HT), noradrenaline, and dopamine). Common treatments for depression are selective serotonin reuptake inhibitors, tricyclic antidepressants, and monoamine oxidase inhibitors, but these drugs have several side effects such as anxiety, diarrhea, constipation, weight loss, and sexual dysfunctions. These agents only reduce the symptoms and temporarily reduce the rate of cognitive impairment associated with depression. As a result, extensive research has recently been conducted on the potential use of antidepressant and sedative herbs. According to the available data, herbs used in traditional medicine can be significantly effective in reducing depression, depressive symptoms and improving patients' performance. The present study provides a summary of biomarkers and therapeutic goals of depression and shows that natural products such as saffron or genipin have antidepressant effects. Some of the useful natural products and their mechanisms were evaluated. Data on various herbs and natural isolated compounds reported to prevent and reduce depressive symptoms is also discussed.

Flavonoids for depression and anxiety: a systematic review and meta-analysis

Natural flavonoids are the most plentiful form of polyphenols. Given the anti-inflammatory and antioxidant properties of flavonoids, researchers discovered that it might be effective in treating depression and anxiety. The effect of flavonoids on depression and anxiety was investigated by a meta-analysis and systematic review. We searched PubMed, Embase, and Medline databases up to October 15, 2021. We selected 11 studies, among them, 10 studies were chosen to evaluate the depression effects of flavonoids and 7 studies were used to assess anxiety disorder. The meta-analysis showed that flavonoids have an overall significant effect on depression (p = 0.004, Hedge's g = -0.487, 95% CI -0.814 to -0.160) and anxiety (p = 0.006, Hedge's g = -0.741, 95% CI -1.266 to -0.217). Subgroup analysis indicated that the symptoms of depression were significantly improved in the studies when the dose of flavonoids was 50-100mg/day or the treatment duration was ≥8weeks. Anxiety symptoms were improved in the studies with the dose of flavonoids was ≥50mg/day. There was no evidence of publication bias. Our findings suggest that flavonoids might improve symptoms of depression and anxiety. However, a small number of participants and studies were included in this meta-analysis. Therefore, the results should be interpreted with caution.

Antidepressant Potential of Quercetin and its Glycoside Derivatives: A Comprehensive Review and Update

Depression is a global health problem with growing prevalence rates and serious impacts on the daily life of patients. However, the side effects of currently used antidepressants greatly reduce the compliance of patients. Quercetin is a flavonol present in fruits, vegetables, and Traditional Chinese medicine (TCM) that has been proved to have various pharmacological effects such as anti-depressant, anti-cancer, antibacterial, antioxidant, anti-inflammatory, and neuroprotective. This review summarizes the evidence for the pharmacological application of quercetin to treat depression. We clarified the mechanisms of quercetin regulating the levels of neurotransmitters, promoting the regeneration of hippocampal neurons, improving hypothalamic-pituitary-adrenal (HPA) axis dysfunction, and reducing inflammatory states and anti-oxidative stress. We also summarized the antidepressant effects of some quercetin glycoside derivatives to provide a reference for further research and clinical application.

Relationship between Immune Cells, Depression, Stress, and Psoriasis: Could the Use of Natural Products Be Helpful?

Psoriasis is one of the most widespread chronic inflammatory skin diseases, affecting about 2%-3% of the worldwide adult population. The pathogenesis of this disease is quite complex, but an interaction between genetic and environmental factors has been recognized with an essential modulation of inflammatory and immune responses in affected patients. Psoriatic plaques generally represent the clinical psoriatic feature resulting from an abnormal proliferation and differentiation of keratinocytes, which cause dermal hyperplasia, skin infiltration of immune cells, and increased capillarity. Some scientific pieces of evidence have reported that psychological stress may play a key role in psoriasis, and the disease itself may cause stress conditions in patients, thus reproducing a vicious cycle. The present review aims at examining immune cell involvement in psoriasis and the relationship of depression and stress in its pathogenesis and development. In addition, this review contains a focus on the possible use of natural products, thus pointing out their mechanism of action in order to counteract clinical and psychological symptoms.

Quercetin Mitigates Methamphetamine-Induced Anxiety-Like Behavior Through Ameliorating Mitochondrial Dysfunction and Neuroinflammation

Methamphetamine (MA) abuse results in neurotoxic outcomes, including increased anxiety and depression. Studies have reported an association between MA exposure and anxiety, nonetheless, the underlying mechanism remains elusive. In the present study, we developed a mouse model of anxiety-like behavior induced by MA administration. RNA-seq was then performed to profile the gene expression patterns of hippocampus (HIPP), and the differentially expressed genes (DEGs) were significantly enriched in signaling pathways related to psychiatric disorders and mitochondrial function. Based on these, mitochondria was hypothesized to be involved in MA-induced anxiety. Quercetin, as a mitochondrial protector, was used to investigate whether to be a potential treatment for MA-induced anxiety; accordingly, it alleviated anxiety-like behavior and improved mitochondrial impairment in vivo. Further experiments in vitro suggested that quercetin alleviated the dysfunction and morphological abnormalities of mitochondria induced by MA, via decreasing the levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and increasing the oxygen consumption rate (OCR) and ATP production. Moreover, the study examined the effect of quercetin on astrocytes activation and neuroinflammation, and the results indicated that it significantly attenuated the activation of astrocytes and reduced the levels of IL-1β, TNFα but not IL-6. In light of these findings, quantitative evidence is presented in the study supporting the view that MA can evoke anxiety-like behavior via the induction of mitochondrial dysfunction. Quercetin exerted antipsychotic activity through modulation of mitochondrial function and neuroinflammation, suggesting its potential for further therapeutic development in MA-induced anxiety.

Folic Acid Attenuates Glial Activation in Neonatal Mice and Improves Adult Mood Disorders Through Epigenetic Regulation

Growing evidence indicates that postnatal immune activation (PIA) can adversely increase the lifetime risk for several neuropsychiatric disorders, including anxiety and depression, which involve the activation of glial cells and early neural developmental events. Several glia-targeted agents are required to protect neonates. Folic acid (FA), a clinical medication used during pregnancy, has been reported to have neuroprotective properties. However, the effects and mechanisms of FA in PIA-induced neonatal encephalitis and mood disorders remain unclear. Here, we investigated the roles of FA in a mouse model of PIA, and found that FA treatment improved depressive- and anxiety-like behaviors in adults, accompanied by a decrease in the number of activated microglia and astrocytes, as well as a reduction in the inflammatory response in the cortex and hippocampus of neonatal mice. Furthermore, we offer new evidence describing the functional differences in FA between microglia and astrocytes. Our data show that epigenetic regulation plays an essential role in FA-treated glial cells following PIA stimulation. In astrocytes, FA promoted the expression of IL-10 by decreasing the level of EZH2-mediated H3K27me3 at its promoter, whereas FA promoted the expression of IL-13 by reducing the promoter binding of H3K9me3 mediated by KDM4A in microglia. Importantly, FA specifically regulated the expression level of BDNF in astrocytes through H3K27me3. Overall, our data supported that FA may be an effective treatment for reducing mood disorders induced by PIA, and we also demonstrated significant functional differences in FA between the two cell types following PIA stimulation.

Anxiolytic and antidepressant-like activities of aqueous extract of Azadirachta indica A. Juss. flower in the stressed rats

The aim of this study was to evaluate whether an aqueous extract of Azadirachta indica A. Juss. (A. indica) flower had anxiolytic and antidepressant-like effects in the stressed rats. Male Wistar rats were randomly allocated to one of two experimental groups: control or stress. The stress groups were received restraint stress for 3 h. The stressed rats were administered a vehicle, diazepam, fluoxetine, and A. indica at doses of 250, 500, and 1000 mg/kg BW for 30 days. The elevated plus-maze test (EPMT), the forced swimming test (FST), and the open field test (OFT) were used to assess anxiolytic and antidepressant-like behaviors. In the EPMT, the percentage of the number of open arm entries and the duration spent in open arms were measured. These measurements were considerably enhanced in the stressed rats treated with diazepam and A. indica flower extract at a dose of 500 mg/kg BW. Furthermore, the stressed rats given fluoxetine and A. indica flower extract at all doses employed in this study showed a significant reduction in the amount of time the rats were immobilized in the FST. However, there was no significant difference in spontaneous locomotor activity between any of the groups. Additionally, the stressed rats treated with either positive control medications or A. indica flower extract exhibited significantly higher brain dopamine (DA) and serotonin (5-HT) levels, but lower blood cortisol levels as compared to the stressed rats treated with vehicle. Moreover, A. indica flower extract had no harmful effect on the stressed rats’ liver tissue.

Inhibitory Effects of Selenium on Arsenic-Induced Anxiety-/Depression-Like Behavior and Memory Impairment

Elevated arsenic (As) contamination in drinking water was detected in many areas of Pakistan. The intoxication of As causes various neurological diseases in humans, which can be inhibited by the administration of potent antioxidants. Trace elements are also found in drinking water such as selenium (Se), which possess antioxidant potential. The main purpose of the current study is to find out the protective effect of Se against As toxicity which can cause anxiety- and depression-like behaviors as well as memory impairment. Thirty-six male rats were divided into six groups: (1) distilled water (dw)+dw, (2) dw+Se (0.175 mg/ml/kg), (3) dw+Se (0.35mg/ml/kg), (4) dw+As (2.5mg/ml/kg), (5) As (2.5mg/ml/kg) + Se (0.175 mg/ml/kg), and (6) As (2.5mg/ml/kg) + Se (0.35 mg/ml/kg). Rats were treated with respective treatment for 4 weeks. Sub-chronic treatment of As reduced time spent in open arm (elevated plus maze), and lightbox (light-dark activity test) and increased immobility time in forced swim test indicate anxiety- and/or depression-like behavior, respectively. Conversely, rats treated with As+Se (at both doses) increased time spent in open arm (elevated plus maze), and lightbox (light-dark activity test) and decreased immobility time in forced swim test indicate the anxiolytic and anti-depressive effect of Se, respectively. Co-administration of Se (0.175 and 0.35) inhibited As instigated reduction of spatial memory performed in Morris water maze. The reversal in the reduced level of malondialdehyde and activity of acetylcholinesterase in the hippocampus by Se was observed in As-treated animals, while the activity of antioxidant enzymes in the hippocampus was increased in As+Se than dw+As-treated animals. Histopathological studies have shown the reversal of hippocampus deterioration by Se in As-treated rats. The results may imply to prevent the intoxication of As instigated impairment in behavioral and biochemical indices by Se supplementation and/or increased safer intake.

Vitamin D2 protects acute and repeated noise stress induced behavioral, biochemical, and histopathological alterations: Possible antioxidant effect

Noise is an environmental stressor which causes distress and hearing loss in individuals residing in urban areas. Psychological deficits such as anxiety, depression, impaired memory and cognitive decline are caused by noise stress. Different vitamins have been used as a potential antioxidant for neuronal protection. In this study we investigate the anxiolytic, antidepressant and memory enhancing effect of vitamin D2 (Vit D2) following noise stress. Thirty-six albino rats were randomly divided into six groups. (i) Unstressed + corn oil (ii) Unstressed + Vit D2 (iii) Acute noise stress + corn oil (iv) Acute noise stress + Vit D2 (v) Repeated noise stress + corn oil (vi) Repeated noise stress + Vit D2. 600 IU/kg body weight of Vit D2 dosage was prepared in corn oil. Corn oil is used as vehicle and all the drugs administered via oral gavage till end of the experiment (day 16). Recorded sound of generator which was amplified by speakers and had 100 dB intensity was used as noise stress. Repeated stressed animals were exposed to noise (4-hrs) daily for 14 days, while acute stressed animals were exposed to noise (4-hrs) once after 14 days. Behavioral tests (elevated plus maze, light dark box, tail suspension test and Morris water maze) of all groups were performed after15 days treatment period. After behavioral tests rats received their last dosage and decapitated after 1-hr. Brain of all animals was removed and used for biochemical (oxidative stress biomarker, antioxidant enzymes and acetylcholinesterase) and histopathological estimations. Results show that Vit D2 decreased time spent in light box and open arm of light dark activity box and elevated plus maze test respectively (used for anxiety evaluation), decreased immobility time in tail suspension test (for depression) and improved cognitive ability evaluated by Morris water maze test in acute and repeated noise stressed rats. Furthermore, increased antioxidant enzymes activity, decreased lipid peroxidation and acetylcholinesterase activity were also observed in Vit D2 treated animals following acute and repeated noise stress. Normalization in histopathological studies was also observed in Vit D2 treated following acute and repeated noise stress. It is concluded that Vit D2 protects from noise stress induced behavioral, biochemical and histopathological impairment through its antioxidant potential.

D-galactose induced dysfunction in mice hippocampus and the possible antioxidant and neuromodulatory effects of selenium

Aging is an ultimate reality that everyone has to face. D-galactose (D-gal) has been used extensively to develop aging model. Trace elements such as selenium (Se) have been used as a potential antioxidant for neuro-protection. The present work aims to develop therapeutic agents such as Se for the treatment of aging-induced neurological ailments such as anxiety, depression, and memory impairment. For this purpose, mice were treated with D-gal at a dose of 300 mg/ml/kg and various doses of Se (0.175 and 0.35mg/ml/kg) for 28 days. Behavioral tests were monitored after treatment days. After the behavioral assessment, mice were decapitated and their brains were collected. Hippocampi were removed from the brain for biochemical, neurochemical, and histopathological analysis. The present findings of behavioral analysis showed that D-gal-induced anxiety- and depression-like symptoms were inhibited by both doses of Se. D-gal-induced memory alteration was also prevented by repeated doses of Se (0.175 and 0.35mg/ml/kg). Biochemical analysis showed that D-gal-induced increase of oxidative stress and inflammatory markers and decrease of antioxidant enzymes and total protein contents in the hippocampus were prevented by Se administration. An increase in the activity of acetylcholinesterase was also diminished by Se. The neurochemical assessment showed that D-gal-induced increased serotonin metabolism and decreased acetylcholine levels in the hippocampus were restored by repeated treatment of Se. Histopathological estimations also exhibited; normalization of D-gal induced neurodegenerative changes. It is concluded that D-gal-induced dysfunction in mice hippocampus caused anxiety, depression, memory impairment, oxidative stress, neuro-inflammation, and histological alterations that were mitigated by Se via its antioxidant potential, anti-inflammatory property, and modulating capability of serotonergic and cholinergic functions.

Dietary Intake of Flavonoids and Carotenoids Is Associated with Anti-Depressive Symptoms: Epidemiological Study and In Silico-Mechanism Analysis

Flavonoids and carotenoids are bioactive compounds that have protective effects against depressive symptoms. Flavonoids and carotenoids are the two main types of antioxidant phytochemicals. This study investigated the association between flavonoid and carotenoid intake and depressive symptoms in middle-aged Korean females. We analyzed the mechanism of these associations using an in silico method. Depressive symptoms were screened using the Beck Depression Inventory-II (BDI-II), and flavonoid and carotenoid intake were assessed using a semi-quantitative food frequency questionnaire. Using a multivariate logistic regression model, we found that flavones, anthocyanins, individual phenolic compounds, lycopene, and zeaxanthin were negatively associated with depressive symptoms. In silico analysis showed that most flavonoids have high docking scores for monoamine oxidase A (MAOA) and monoamine oxidase B (MAOB), which are two important drug targets in depression. The results of the docking of brain-derived neurotrophic factor (BDNF) and carotenoids suggested the possibility of allosteric activation of BDNF by carotenoids. These results suggest that dietary flavonoids and carotenoids can be utilized in the treatment of depressive symptoms.

Effects of flavonols on emotional behavior and compounds of the serotonergic system: A preclinical systematic review

Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter that regulates multiple psychophysiological functions. An imbalance of 5-HT in the brain can modulate emotional behavior such as depression and anxiety. Substances, such as flavonols, naturally found in some plants and foods have beneficial effects on psychiatric disorders, have been studied. The aim of this systematic review was to investigate the effects of flavonols on morphological, physiological, and cellular aspects of the serotonergic system as well as on some behaviors modulated by this system. Literature searches were performed in the LILACS, Web of Science, Scopus, PubMed and Sigle via Open Grey databases, from which 1725 studies were found. Using a predefined protocol registered on the CAMARADES website, 18 studies were chosen for qualitative synthesis. Internal validity was assessed using the SYRCLE's risk of bias tool. The Kappa index was also measured to analyze agreement among the reviewers. The results of this systematic review showed that flavonols have been reported to modify physiological aspects of the serotonergic system, increasing levels of serotonin and decreasing levels of its metabolite, 5-hydroxyindoleacetic acid (5-HIAA) and promoting antioxidant effects in encephalic regions. Moreover, the results showed that flavonols can also modulate of the serotonergic system, being associated with antidepressant and anxiolytic activities. Additionally, flavonols were found to not have psychostimulant effect; they can, however, reverse damage to locomotor activity.

Reserpine-induced altered neuro-behavioral, biochemical and histopathological assessments prevent by enhanced antioxidant defence system of thymoquinone in mice

Thymoquinone (Tq), an active compound of Nigella sativa, has been known for its anti-inflammatory, antioxidant, and neuroprotective characteristics. The present study is aimed to evaluate the effect of Tq on reserpine (Rsp)-induced behavioral (anxiety and/or depression) and, memory deficit; hippocampal inflammatory markers, oxidative markers, antioxidant enzymes, acetylcholinesterase (AChE) activity and histopathology in male mice. Animals were injected with Rsp at a dose of 2 mg/ml/kg and doses of Tq (10 and 20 mg/ml/kg) for 28 days. After the treatment period, behavioral tests [Elevated plus maze (Epm); Light dark box test (Lda); Morris water maze (Mwm); Forced swim test (Fst); Tail suspension test (Tst)] were conducted. After analysis of behaviors, mice were decapitated and brain samples were collected, the hippocampus was removed from the whole-brain sample for biochemical analysis and histology. Administration of Tq at both doses prevent adverse effects of Rsp and increased time spent in open arm and lightbox in Lda and Epm respectively, decreased immobility period in Fst and Tst, decreased latency escape in Mwm, reduced lipid peroxidation (lpo) and inflammatory cytokines, increased defensive enzymes, reduced acetylcholinesterase (AChE) activity and corrected histological lines. It is concluded that Rsp-instigated behavioral and memory deficits were prevented by Tq possibly via its strong antioxidant and anti-inflammatory effects.

A subchronic low-dose exposure of a glyphosate-based herbicide induces depressive and anxious-like behavior in mice: quercetin therapeutic approach

In this study, we investigated the possible role of pesticide exposure in contributing to neurological diseases such as depression. Here, we evaluated whether a subchronic low dose of a glyphosate-based herbicide (GBH) could induce alterations in the central nervous system, using the flavonoid quercetin as a therapeutic strategy. Forty mice were divided into four treatment groups: control, GBH, quercetin, and GBH+Quer groups and received 50 mg/kg of GBH solution, 30 mg/kg of quercetin, and/or vehicles for 30 days via gavage. After performing behavioral tests, such as the open field (OF), elevated plus maze (EPM), forced swim test (FST), and sucrose preference test (SPT), the mice were euthanized and their hippocampal tissues were collected to measure the levels of oxidative stress markers such as reactive species (RS), total antioxidant capacity (FRAP), reduced glutathione (GSH), and acetylcholinesterase activity (AChE), as well as for histological evaluation. The GBH group showed anxious and depressive-like behavior in the EPM and FST tests, as well as increased levels of RS and decreased GSH levels in the hippocampus. Quercetin treatment in the GBH+Quer group allowed partial or total improvement in behavioral tests (EPM and FST) and in the levels of oxidative stress markers (RS and GSH). However, the quercetin group showed similar behavior to the GBH group after treatment. The results revealed that oral exposure to a subchronic low dose of GBH was capable of promoting effects on behavior and oxidative stress in the hippocampus of mice. In addition, despite quercetin having a neuroprotective role, caution is needed when considering the possible per se effects of its continuous supplementation.

3D-ALMOND-QSAR Models to Predict the Antidepressant Effect of Some Natural Compounds

The current treatment of depression involves antidepressant synthetic drugs that have a variety of side effects. In searching for alternatives, natural compounds could represent a solution, as many studies reported that such compounds modulate the nervous system and exhibit antidepressant effects. We used bioinformatics methods to predict the antidepressant effect of ten natural compounds with neuroleptic activity, reported in the literature. For all compounds we computed their drug-likeness, absorption, distribution, metabolism, excretion (ADME), and toxicity profiles. Their antidepressant and neuroleptic activities were predicted by 3D-ALMOND-QSAR models built by considering three important targets, namely serotonin transporter (SERT), 5-hydroxytryptamine receptor 1A (5-HT1A), and dopamine D2 receptor. For our QSAR models we have used the following molecular descriptors: hydrophobicity, electrostatic, and hydrogen bond donor/acceptor. Our results showed that all compounds present drug-likeness features as well as promising ADME features and no toxicity. Most compounds appear to modulate SERT, and fewer appear as ligands for 5-HT1A and D2 receptors. From our prediction, linalyl acetate appears as the only ligand for all three targets, neryl acetate appears as a ligand for SERT and D2 receptors, while 1,8-cineole appears as a ligand for 5-HT1A and D2 receptors.