Apigenin reverses depression-like behavior induced by chronic corticosterone treatment in mice

Comparing the effect of fluoxetine, escitalopram, and sertraline, on the level of BDNF and depression in preclinical and clinical studies: a systematic review

Brain-derived neurotrophic factor (BDNF) dysfunction is one of the most important mechanisms underlying depression. It seems that selective serotonin reuptake inhibitors (SSRIs) improve depression via affecting BDNF level. In this systematic review, for the first time, we aimed to review the effect of three SSRIs including fluoxetine, escitalopram, and sertraline, on both depression and BDNF level in preclinical and clinical studies. PubMed electronic database was searched, and 193 articles were included in this study. After reviewing all manuscripts, only one important difference was found: subjects. We found that SSRIs induce different effects in animals vs. humans. Preclinical studies showed many controversial effects, while human studies showed only two effects: improvement of depression, with or without the improvement of BDNF. However, most studies used chronic SSRIs treatment, while acute SSRIs were not effectively used and evaluated. In conclusion, it seems that SSRIs are reliable antidepressants, and the improvement effect of SSRIs on depression is not dependent to BDNF level (at least in human studies).

Apigenin: A Bioflavonoid with a Promising Role in Disease Prevention and Treatment

Apigenin is a powerful flavone compound found in numerous fruits and vegetables, and it offers numerous health-promoting benefits. Many studies have evidenced that this compound has a potential role as an anti-inflammatory and antioxidant compound, making it a promising candidate for reducing the risk of pathogenesis. It has also been found to positively affect various systems in the body, such as the respiratory, digestive, immune, and reproductive systems. Apigenin is effective in treating liver, lung, heart, kidney, neurological diseases, diabetes, and maintaining good oral and skin health. Multiple studies have reported that this compound is capable of suppressing various types of cancer through the induction of apoptosis and cell-cycle arrest, suppressing cell migration and invasion, reduction of inflammation, and inhibiting angiogenesis. When used in combination with other drugs, apigenin increases their efficacy, reduces the risk of side effects, and improves the response to chemotherapy. This review broadly analyzes apigenin's potential in disease management by modulating various biological activities. In addition, this review also described apigenin's interaction with other compounds or drugs and the potential role of nanoformulation in different pathogeneses. Further extensive research is needed to explore the mechanism of action, safety, and efficacy of this compound in disease prevention and treatment.

Apigenin: a natural molecule at the intersection of sleep and aging

NAD+, a pivotal coenzyme central to metabolism, exhibits a characteristic decline with age. In mice, NAD+ levels can be elevated via treatment with apigenin, a natural flavonoid that inhibits the NAD+-consuming glycoprotein CD38. In animal models, apigenin positively impacts both sleep and longevity. For example, apigenin improves learning and memory in older mice, reduces tumor proliferation in a mouse xenograft model of triple-negative breast cancer, and induces sedative effects in mice and rats. Moreover, apigenin elongates survival in fly models of neurodegenerative disease and apigenin glycosides increase lifespan in worms. Apigenin's therapeutic potential is underscored by human clinical studies using chamomile extract, which contains apigenin as an active ingredient. Collectively, chamomile extract has been reported to alleviate anxiety, improve mood, and relieve pain. Furthermore, dietary apigenin intake positively correlates with sleep quality in a large cohort of adults. Apigenin's electron-rich flavonoid structure gives it strong bonding capacity to diverse molecular structures across receptors and enzymes. The effects of apigenin extend beyond CD38 inhibition, encompassing agonistic and antagonistic modulation of various targets, including GABA and inflammatory pathways. Cumulatively, a large body of evidence positions apigenin as a unique molecule capable of influencing both aging and sleep. Further studies are warranted to better understand apigenin's nuanced mechanisms and clinical potential.

Dietary flavonoid intake is associated with a lower risk of depressive symptoms in US adults: Data from NHANES 2007-2008, 2009-2010, and 2017-2018

BACKGROUND

Depressive symptoms is an important public health problem. The aim of the present study is to examine the association of dietary flavonoid intake with risk of depressive symptoms.

METHODS

In this study, we conducted an assessment to investigate the potential association between dietary flavonoid intake and the risk of depressive symptoms. Our analysis was based on a nationally representative sample of 9674 adults who participated in the 2007-2010 and 2017-2018 National Health and Nutrition Examination Surveys. Flavonoid intake was measured using a 24-hour dietary recall method, while depressive symptoms was evaluated using the Patient Health Questionnaire-9. To examine the relationship between dietary flavonoid intake and the risk of depressive symptoms, we employed logistic regression, subgroup and restricted cubic spline models.

RESULTS

Following multivariate adjustment, the study found a negative association between total flavonoids, anthocyanidins, flavanones, flavones, isoflavones and the risk of depressive symptoms. In subgroup analysis, total flavonoid intake was inversely associated with risk of depressive symptoms among women whereas no association was found among man. Additionally, a non-linear relationship was observed between total flavonoid intake and depressive symptoms, with statistical significance (P for nonlinearity <0.001).

LIMITATIONS

The present study employed a cross-sectional design, which precludes the establishment of causality. Furthermore, the data relied on self-reported measures.

CONCLUSIONS

In present study, moderate total flavonoids intake, but not high intake, was associated with lower odds of depressive symptoms suggesting a U-shaped association.

The Beneficial Role of Apigenin against Cognitive and Neurobehavioural Dysfunction: A Systematic Review of Preclinical Investigations

Apigenin is a flavone widely present in different fruits and vegetables and has been suggested to possess neuroprotective effects against some neurological disorders. In this study, we systematically reviewed preclinical studies that investigated the effects of apigenin on learning and memory, locomotion activity, anxiety-like behaviour, depressive-like behaviour and sensorimotor and motor coordination in rats and mice with impaired memory and behaviour. We searched SCOPUS, Web of Science, PubMed and Google Scholar for relevant articles. A total of 34 studies were included in this review. The included studies revealed that apigenin enhanced learning and memory and locomotion activity, exhibited anxiolytic effects, attenuated depressive-like behaviour and improved sensorimotor and motor coordination in animals with cognitive impairment and neurobehavioural deficit. Some of the molecular and biochemical mechanisms of apigenin include activation of the ERK/CREB/BDNF signalling pathway; modulation of neurotransmitter levels and monoaminergic, cholinergic, dopaminergic and serotonergic systems; inhibition of pro-inflammatory cytokine production; and attenuation of oxidative neuronal damage. These results revealed the necessity for further research using established doses and short or long durations to ascertain effective and safe doses of apigenin. These results also point to the need for a clinical experiment to ascertain the therapeutic effect of apigenin.

Corticosterone effects on postnatal cerebellar development in mice

Glucocorticoids administered early in infancy can affect the architectonic organization of brain structures, particularly those with a postnatal development and resulting in long-term deficits of neuromotor function and cognition. The present study was undertaken to study the effects of daily corticosterone (CORT) injections at a pharmacological dose from postnatal days 8-15 on cerebellar and hippocampal development in mouse pups. Gene expression status for trophic factors involved in synaptic development and function as well as measures of layer thickness associated with cytochrome oxidase labelling were analyzed in the hippocampus, hypothalamus, and specific cerebellar lobules involved in motor control. Repeated CORT injections dysregulated the HPA axis with increased Crh and Nr3c1 mRNA levels in the hypothalamus and a resulting higher serum corticosterone level. The CORT treatment altered the morphology of the hippocampus and down-regulated gene transcription for corticotropin-releasing hormone (Crh) and its type-1 receptor (Crhr1), glucocorticoid receptor (Nr3c1), and brain-derived neurotrophic factor Bdnf and its receptor Ntrk2 (neurotrophic receptor tyrosine kinase 2). Similar mRNA expression decreases were found in the cerebellum for Crhr1, Crhr2, Nr3c1, and Grid2 (glutamatergic δ2 receptor). Morphological alterations and metabolic activity variations were observed in specific cerebellar lobules involved in motor control. The paramedian lobule, normally characterized by mitotic activity in the external germinative layer during the second postnatal week, was atrophic but metabolically hyperactive in its granule cell and molecular layers. On the contrary, lobules with an earlier cell proliferation displayed neurogenesis but a hypoactivated granule cell layer, suggesting a developmental delay in synaptogenesis. The results indicate that glucocorticoid, administered daily during the second postnatal week modulated the developmental programming of the hippocampus and cerebellum. These growth and metabolic alterations may lead possibly to morphological and functional changes later in life.

Molecular basis of breast cancer with comorbid depression and the mechanistic insights of Xiaoyaosan in treating breast cancer-associated depression

Depression and breast cancer (BC) have been found to have a shared genetic basis, multiple loci of effect, and a presumed causal relationship. The treatment of BC combined with depression poses significant challenges. This study aims to use bioinformatics and network pharmacology to explore the molecular basis of BC combined with depression and to elucidate the potential mechanisms of Xiaoyaosan (XYS) in treating this disease. The molecular background of BC complicated with depression was discovered via data mining and bioinformatics. The molecular mechanism of XYS in the treatment of BC with depression was investigated by network pharmacology. The binding affinity between targets and active compounds was evaluated by molecular docking. The impact of XYS on the gene and protein expression of matrix metallopeptidase 9 (MMP9) in microglial cells was assessed using RT-quantitative PCR and western blot analysis, respectively. Differential expression analysis was conducted to identify genes associated with BC, revealing that 2958 genes were involved, with 277 of these genes also being related to depression. XYS was found to contain 173 active compounds and 342 targets, with 44 of these targets being involved in regulating the progression of BC and depression. Enrichment analysis was performed to identify pathways associated with these targets, revealing that they were related to cell proliferation, catalytic activity, cell communication, and interleukin-18 signaling and LXR/RXR activation. Network analysis was conducted to identify key targets of Xiaoyaosan in treating BC combined with depression, with EGF, interleukin 6, epidermal growth factor receptor, and peroxisome proliferator activated receptor gamma being identified as important targets. Molecular docking was also performed to assess the binding affinity between key targets and active compounds, with puerarin showing the strongest affinity for MMP9. In microglial cells, XYS significantly enhances the gene and protein expression of MMP9. This study elucidated the pharmacological mechanism of co-treatment for BC patients complicated with depression and the pharmacological mechanism of XYS against BC plus depression.

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.

Naringenin and apigenin ameliorates corticosterone-induced depressive behaviors

Background

Depression is a common kind of mental illness, and it becomes the main health burden in the world.

Purpose

The aim of this study was to investigate the antidepressant effects of naringin and apigenin isolated from Chrysanthemum morifolium Ramatis.

Methods

Firstly, 20 mg/kg corticosterone (CORT) was injected into mice to establish an in vivo model of depression. After treated with different dosages of naringenin and apigenin for 3 weeks, the mice underwent a series of behavioral experiments. Following this, all mice were sacrificed and biochemical analyses were performed. Subsequently, CORT (500 μM) induced PC12 cells was used as an in vitro model of depression, and lipopolysaccharide (LPS) (1 μg ml^-1) induced N9 microglia cells was used as an in vitro model of neuroinflammation in N9 microglia cells, to investigate the neuroprotective mechanisms of naringenin and apigenin.

Results

Results showed that the naringenin and apigenin treatment ameliorated CORT-induced sucrose preference decrease and immobility time increase, elevated the 5-hydroxytryptamine(5-HT), dopamine (DA) and norepinephrine (NE) levels, and enhanced the cAMP-response element binding protein (CREB) and brain derived neurotrophic factor (BDNF) protein expressions in the hippocampus. The results showed that the naringenin and apigenin treatment improved the PC-12 cell viability through reducing apoptosis rate induced by CORT. Furthermore, naringenin and apigenin were able to inhibit the activation of N9 cells after LPS induction, and shift microglia from proinflammatory M1 microglia toward anti-inflammatory M2 microglia, as evidenced by the decreased ratio of M1 type microglia marker CD86 and M2 type microglia marker CD86.

Conclusion

These results suggested that naringenin and apigenin may improve depressive behaviors through promoting BDNF and inhibiting neuroinflammation and neuronal apoptosis.

Exploring the multifocal role of phytoconstituents as antidepressants

Depression is the most prevalent and devastating neuropsychiatric disorder. There are several conventional antidepressants used for the treatment of depression. But due to their undesired adverse effects, patient compliance is very poor. Thus, developing novel medications for the treatment of depression is a critical strategic priority for meeting therapeutic demands. Current research is looking for alternatives to traditional antidepressants to reduce undesired side effects and increase efficacy. Phytoconstituents provide a wide research range in antidepressant treatments. In the present article, we have conducted a comprehensive assessment of neurological evidence, which supports the usefulness of phytoconstituents in the treatment of the depressive disorder. Secondary plant metabolites including alkaloids, polyphenols, glycosides, saponins, and terpenoids were found to exhibit antidepressant action. Most of the phytoconstituents were found to mediate their antidepressant effect through the upregulation of brain-derived neurotrophic factor (BDNF), serotonin, noradrenaline, and dopamine. Some were also found to exert antidepressant effects by inhibiting the monoamine oxidase (MAO) activity and hypothalamic-pituitary-adrenal (HPA) axis overactivity.

Phytochemicals That Act on Synaptic Plasticity as Potential Prophylaxis against Stress-Induced Depressive Disorder

Depression is a neuropsychiatric disorder associated with persistent stress and disruption of neuronal function. Persistent stress causes neuronal atrophy, including loss of synapses and reduced size of the hippocampus and prefrontal cortex. These alterations are associated with neural dysfunction, including mood disturbances, cognitive impairment, and behavioral changes. Synaptic plasticity is the fundamental function of neural networks in response to various stimuli and acts by reorganizing neuronal structure, function, and connections from the molecular to the behavioral level. In this review, we describe the alterations in synaptic plasticity as underlying pathological mechanisms for depression in animal models and humans. We further elaborate on the significance of phytochemicals as bioactive agents that can positively modulate stress-induced, aberrant synaptic activity. Bioactive agents, including flavonoids, terpenes, saponins, and lignans, have been reported to upregulate brain-derived neurotrophic factor expression and release, suppress neuronal loss, and activate the relevant signaling pathways, including TrkB, ERK, Akt, and mTOR pathways, resulting in increased spine maturation and synaptic numbers in the neuronal cells and in the brains of stressed animals. In clinical trials, phytochemical usage is regarded as safe and well-tolerated for suppressing stress-related parameters in patients with depression. Thus, intake of phytochemicals with safe and active effects on synaptic plasticity may be a strategy for preventing neuronal damage and alleviating depression in a stressful life.

Phytotherapy of mood disorders in the light of microbiota-gut-brain axis

BACKGROUND

Clinical research in natural product-based psychopharmacology has revealed a variety of promising herbal medicines that may provide benefit in the treatment of mild mood disorders, however failed to unambiguously indicate pharmacologically active constituents. The emerging role of the microbiota-gut-brain axis opens new possibilities in the search for effective methods of treatment and prevention of mood disorders.

PURPOSE

Considering the clinically proven effectiveness juxtaposed with inconsistencies regarding the indication of active principles for many medicinal plants applied in the treatment of anxiety and depression, the aim of the review is to look at their therapeutic properties from the perspective of the microbiota-gut-brain axis.

METHOD

A literature-based survey was performed using Scopus, Pubmed, and Google Scholar databases. The current state of knowledge regarding Hypericum perforatum, Valeriana officinalis, Piper methysticum, Passiflora incarnata, Humulus lupulus, Melissa officinalis, Lavandula officinalis, and Rhodiola rosea in terms of their antimicrobial activity, bioavailability, clinical effectiveness in depression/anxiety and gut microbiota - natural products interaction was summarized and analyzed.

RESULTS

Recent studies have provided direct and indirect evidence that herbal extracts and isolated compounds are potent modulators of gut microbiota structure. Additionally, some of the formed postbiotic metabolites exert positive effects and ameliorate depression-related behaviors in animal models of mood disorders. The review underlines the gap in research on natural products - gut microbiota interaction in the context of mood disorders.

CONCLUSION

Modification of microbiota-gut-brain axis by natural products is a plausible explanation of their therapeutic properties. Future studies evaluating the effectiveness of herbal medicine and isolated compounds in treating mild mood disorders should consider the bidirectional interplay between phytoconstituents and the gut microbiota community.

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.

Potential Antioxidant Activity of Apigenin in the Obviating Stress-Mediated Depressive Symptoms of Experimental Mice

This study aimed to examine the antidepressant properties of apigenin in an experimental mouse model of chronic mild stress (CMS). Three weeks following CMS, albino mice of either sex were tested for their antidepressant effects using the tail suspension test (TST) and the sucrose preference test. The percentage preference for sucrose solution and the amount of time spent immobile in the TST were calculated. The brain malondialdehyde (MDA) levels, catalase activity, and reduced glutathione levels were checked to determine the antioxidant potential of treatments. When compared to the control, animals treated with apigenin during the CMS periods showed significantly shorter TST immobility times. Apigenin administration raised the percentage preference for sucrose solution in a dose-dependent manner, which put it on par with the widely used antidepressant imipramine. Animals treated with apigenin displayed a significantly (p ˂ 0.05) greater spontaneous locomotor count (281) when compared to the vehicle-treated group (245). Apigenin was also highly effective in significantly (p ˂ 0.01) lowering plasma corticosterone levels (17 vs. 28 µg/mL) and nitrite (19 vs. 33 µg/mL) produced by CMS in comparison to the control group. During CMS, a high dose (50 mg/kg) of apigenin was given, which greatly increased the reduced glutathione level while significantly decreasing the brain's MDA and catalase activity when compared to the control group. As a result, we infer that high doses of apigenin may have potential antidepressant effects in animal models via various mechanisms.

Interactions of Apigenin and Safranal with the 5HT1A and 5HT2A Receptors and Behavioral Effects in Depression and Anxiety: A Molecular Docking, Lipid-Mediated Molecular Dynamics, and In Vivo Analysis

BACKGROUND

The current study utilizes in silico molecular docking/molecular dynamics to evaluate the binding affinity of apigenin and safranal with 5HT1AR/5HT2AR, followed by assessment of in vivo effects of these compounds on depressive and anxious behavior.

METHODS

The docking between apigenin and safranal and the 5HT1A and 5HT2A receptors was performed utilizing AutoDock Vina software, while MD and protein-lipid molecular dynamics simulations were executed by AMBER16 software. For in vivo analysis, healthy control (HC), disease control (DC), fluoxetine-, and apigenin-safranal-treated rats were tested for changes in depression and anxiety using the forced swim test (FST) and the elevated plus-maze test (EPMT), respectively.

RESULTS

The binding affinity estimations identified the superior interacting capacity of apigenin over safranal for 5HT1A/5HT2A receptors over 200 ns MD simulations. Both compounds exhibit oral bioavailability and absorbance. In the rodent model, there was a significant increase in the overall mobility time in the FST, while in the EPMT, there was a decrease in latency and an increase in the number of entries for the treated and HC rats compared with the DC rats, suggesting a reduction in depressive/anxiety symptoms after treatment.

CONCLUSIONS

Our analyses suggest apigenin and safranal as prospective medication options to treat depression and anxiety.

Antidepressive Effect of Natural Products and Their Derivatives Targeting BDNF-TrkB in Gut-Brain Axis

Modern neurological approaches enable detailed studies on the pathophysiology and treatment of depression. An imbalance in the microbiota-gut-brain axis contributes to the pathogenesis of depression. This extensive review aimed to elucidate the antidepressive effects of brain-derived neurotrophic factor (BDNF)-targeting therapeutic natural products and their derivatives on the gut-brain axis. This information could facilitate the development of novel antidepressant drugs. BDNF is crucial for neuronal genesis, growth, differentiation, survival, plasticity, and synaptic transmission. Signaling via BDNF and its receptor tropomyosin receptor kinase B (TrkB) plays a vital role in the etiopathogenesis of depression and the therapeutic mechanism of antidepressants. This comprehensive review provides information to researchers and scientists for the identification of novel therapeutic approaches for neuropsychiatric disorders, especially depression and stress. Future research should aim to determine the possible causative role of BDNF-TrkB in the gut-brain axis in depression, which will require further animal and clinical research as well as the development of analytical approaches.

Antiproliferative effects of dried Moringa oleifera leaf extract on human Wharton's Jelly mesenchymal stem cells

Mesenchymal stem cells (MSCs) have seen an elevated use in clinical works like regenerative medicine. Its potential therapeutic properties increases when used in tandem with complementary agents like bio-based materials. Therefore, the present study is the first to investigate the cytotoxicity of a highly valued medicinal plant, Moringa oleifera, on human Wharton's Jelly mesenchymal stem cells (hWJMSCs) and its effects on the cells' gene expression when used as a pre-treatment agent in vitro. M. oleifera leaves (MOL) were dried and subjected to UHPLC-QTOF/MS analysis, revealing several major compounds like apigenin, kaempferol, and quercetin in the MOL, with various biological activities like antioxidant and anti-cancer properties. We then treated the hWJMSCs with MOL and noticed a dose-dependant inhibition on the cells' proliferation. RNA-sequencing was performed to explain the possible mechanism of action and revealed genes like PPP1R1C, SULT2B1, CDKN1A, mir-154 and CCNB1, whose expression patterns were closely associated with the negative cell cycle regulation and cell cycle arrest process. This is also evident from gene set enrichment analysis where the GO and KEGG terms for down-regulated pathways were closely related to the cell cycle regulation. The Ingenuity pathway analysis (IPA) software further predicted the significant activation of (p < 0.05, z-score > 2) of the G2/M DNA damage checkpoint regulation pathway. The present study suggests that MOL exhibits an antiproliferative effect on hWJMSCs via cell cycle arrest and apoptotic pathways. We believe that this study provides an important baseline reference for future works involving MOL's potential to accompany MSCs for clinical works. Future works can take advantage of the cell's strong anti-cancer gene expression found in this study, and evaluate our MOL treatment on various cancer cell lines.

Participation of the Serotonergic System and Brain-Derived Neurotrophic Factor in the Antidepressant-like Effect of Flavonoids

Depressive disorders are among the most disabling diseases experienced around the world, and their incidence has significantly increased over the last few decades due to multiple environmental, social, and biological factors. The search for new pharmacological alternatives to treat depression is a global priority. In preclinical research, molecules obtained from plants, such as flavonoids, have shown promising antidepressant-like properties through several mechanisms of action that have not been fully elucidated, including crossing of the blood brain barrier (BBB). This review will focus on discussing the main findings related to the participation of the serotonergic system and brain-derived neurotrophic factor (BDNF) on the antidepressant-like effect of some flavonoids reported by behavioral, neurochemical, and molecular studies. In this sense, evidence shows that depressive individuals have low levels of serotonin and BDNF, while flavonoids can reverse it. Finally, the elucidation of the mechanism used by flavonoids to modulate serotonin and BDNF will contribute to our understanding of the neurobiological bases underlying the antidepressant-like effects produced by these natural compounds.

Potential antidepressant effects of a dietary supplement from the chlorella and lion's mane mushroom complex in aged SAMP8 mice

Since the 1990s, the prevalence of mental illnesses, such as depression, has been increasing annually and has become a major burden on society. Due to the many side effects of antidepressant drugs, the development of a complementary therapy from natural materials is an urgent need. Therefore, this study used a complex extract of chlorella and lion's mane mushroom and evaluated its antidepressant effects. Six-month-old male senescence-accelerated mice prone-8 (SAMP8) were divided into positive control; negative control; and low, medium, and high-dose groups. All groups were treated with corticosterone (CORT) at 40 mg/Kg/day for 21- days to induce depression in the animals, and the effects of different test substances on animal behavior was observed. The positive control group was intraperitoneally injected with a tricyclic antidepressant (Fluoxetine, as tricyclic antidepressant), the control group was given ddH₂O, and the test substance groups were administered test samples once daily for 21 days. The open field test (OFT) and forced swimming test (FST) were applied for behavior analyses of depression animal models. The OFT results showed that the mice in the positive control and the medium-, and high-dose groups demonstrated a significantly prolonged duration in the central area and a significantly increased travel distance. In the FST, the positive control and the medium, and high-dose groups displayed significantly reduced immobility times relative to the control group. The blood analysis results showed significant decreases in triglyceride and blood urea nitrogen levels relative to the positive control and the medium- and high-dose groups. Notably, in the positive control and the medium- and high-dose groups, brain-derived neurotrophic factor (BDNF) increase by more than in the control group. In summary, medium and high dose of extract of chlorella and lion's mane mushroom could improve depression behavior in animals and have the potential to be antidepressant health care products.

Pathophysiology of Depression: Stingless Bee Honey Promising as an Antidepressant

Depression is a debilitating psychiatric disorder impacting an individual’s quality of life. It is the most prevalent mental illness across all age categories, incurring huge socio-economic impacts. Most depression treatments currently focus on the elevation of neurotransmitters according to the monoamine hypothesis. Conventional treatments include tricyclic antidepressants (TCAs), norepinephrine–dopamine reuptake inhibitors (NDRIs), monoamine oxidase inhibitors (MAOIs), and serotonin reuptake inhibitors (SSRIs). Despite numerous pharmacological strategies utilising conventional drugs, the discovery of alternative medicines from natural products is a must for safer and beneficial brain supplement. About 30% of patients have been reported to show resistance to drug treatments coupled with functional impairment, poor quality of life, and suicidal ideation with a high relapse rate. Hence, there is an urgency for novel discoveries of safer and highly effective depression treatments. Stingless bee honey (SBH) has been proven to contain a high level of antioxidants compared to other types of honey. This is a comprehensive review of the potential use of SBH as a new candidate for antidepressants from the perspective of the monoamine, inflammatory and neurotrophin hypotheses.

Recovery from Traumatic Brain Injury Following Treatment with Δ9-Tetrahydrocannabinol Is Associated with Increased Expression of Granulocyte-Colony Stimulating Factor and Other Neurotrophic Factors

Introduction: The hematopoietic cytokine granulocyte-colony stimulating factor (G-CSF) is well known to stimulate proliferation of blood stem/progenitor cells of the leukocyte lineage, but is also recognized as a neurotrophic factor involved in brain self-repair processes. G-CSF administration has been shown to promote recovery from experimental models of traumatic brain injury (TBI) and to modulate components of the endocannabinoid system (eCS). Conversely, Δ9-tetrahydrocannabinol (Δ9THC) treatment of normal mice has been shown to increase blood levels of G-CSF in the periphery. Hypothesis: Administration of the phytocannabinoid Δ9THC will enhance brain repair following controlled cortical impact (CCI) by upregulating G-CSF and other neurotrophic factors (brain-derived neurotrophic factor [BDNF] and glial-derived neurotrophic factor [GDNF]) in brain regions. Materials and Methods: C57BL/6J mice underwent CCI and were treated for 3 days with THC 3 mg/kg intraperitoneally. Motor function on a rotarod was recorded at baseline and 3, 7, and 14 days after CCI. Groups of mice were euthanized at 7 and 14 days. G-CSF, BDNF, and GDNF expression were measured at 7 and 14 days in cerebral cortex, striatum, and hippocampus on the side of the trauma. Results: Δ9THC-treated mice ran on the rotarod longer than vehicle-treated mice and recovered to normal rotarod performance levels at 2 weeks. These mice, compared to vehicle-treated animals, exhibited significant upregulation of G-CSF as well as BDNF and GDNF in cerebral cortex, striatum, and hippocampus. Conclusion: Administration of the phytocannabinoid Δ9THC promotes significant recovery from TBI and is associated with upregulation of brain G-CSF, BDNF, and GDNF, neurotrophic factors previously shown to mediate brain self-repair following TBI and stroke.

Targeting autophagy and neuroinflammation pathways with plant-derived natural compounds as potential antidepressant agents

Major depressive disorder (MDD) is a life-threatening disease that presents several characteristics. The pathogenesis of depression still remains poorly understood. Moreover, the mechanistic interactions of natural components in treating depression to target autophagy and neuroinflammation are yet to be evaluated. This study overviewed the effects of plant-derived natural components in regulating critical pathways, particularly neuroinflammation and autophagy, associated with depression. A list of natural components, including luteolin, apigenin, hyperforin, resveratrol, salvianolic acid b, isoliquiritin, nobiletin, andrographolide, and oridonin, have been investigated. All peer-reviewed journal articles were searched by Scopus, MEDLINE, PubMed, Web of Science, and Google Scholar using the appropriated keywords, including depression, neuroinflammation, autophagy, plant, natural components, etc. The neuroinflammation and autophagy dysfunction are critically associated with the pathophysiology of depression. Natural components with higher efficiency and lower complications can be used for targeting neuroinflammation and autophagy. These components with different doses showed the beneficial antidepressant properties in rodents. These can modulate autophagy markers, mainly AMPK, LC3II/LC3I ratio, Beclin-1. Moreover, they can regulate the NLRP3 inflammasome, resulting in the suppression of proinflammatory cytokines (e.g., IL-1β and IL-18). Future in vitro and in vivo studies are required to develop novel therapeutic approaches based on plant-derived active components to treat MDD.

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.

The possible mechanism of Datura stramonium on pentobarbital-induced sleep in mice

BACKGROUND

Insomnia leads to the development of mental problems and missing of accuracy in affected persons. Various investigations have previously revealed which medicinal plants play a role in the improvement of insomnia. In this study, we evaluated the effect of hydro-alcoholic extract of Datura stramonium on insomnia in mice.

METHODS

The extracts and fractions at different concentrations were injected intraperitoneally (i.p.) to mice 30 min before the sodium pentobarbital (30 mg/kg, i.p.). Additionally, the blood was collected from cardiac and serum separated to measure brain-derived neurotrophic factor (BDNF). The LC-MS was done to identify the active components. Flumazenil or naloxone were also applied to study the possible mechanism of extract. The PC12 cells were then exposed to different doses of extract and fractions, in order to evaluate cytotoxicity by MTT assay and the measured LD₅₀.

RESULTS

The hydro-alcoholic extracts of calyx, seed and petal elevated sleep duration and decreased sleep latency. In addition, water, ethyl acetate and n-butanol fractions of hydro-alcoholic extract of petal increased sleep duration. Of note, Naloxone significantly reversed the hypnotic effect of the extract. The extract increased the level of BDNF in serums. As well, the toxicity assessment revealed that the extracts had not toxic on PC12 cells. The LD₅₀ value was obtained as 4.8 g/kg.

CONCLUSION

This research demonstrated that D. stramonium (including seed, petal and calyx) increased the hypnotic effect without neurotoxicity on PC12 cells. Sleep induction may be related to its active ingredients as well as the effect on opioid receptors.

Protective effect of Myrcia pubipetala Miq. against the alterations in oxidative stress parameters in an animal model of depression induced by corticosterone

Depression is a debilitating disorder in humans that significantly affects quality of life. As such, alternative therapies are highly sought after by patients seeking treatment for depression. Experimentally, the chronic administration of corticosterone (CORT) in rodents has been reported to promote depressive-like behaviors. Herein, animals received saline or CORT for 21 days and, during the last 7 days, they were treated with the crude hydroalcoholic extract (CHE) of Myrcia pubipetala Miq (50, 100 or 150 mg/Kg), or vehicle (distilled water), by oral route. After 24 h, animals were subjected to the open field (OFT) and forced swimming tests (FST), and then sacrificed for the removal of the hippocampus and cerebral cortex for biochemical analysis. Results showed enhanced catalase (CAT) and superoxide dismutase (SOD) activities, as well as an elevated formation of thiobarbituric acid reactive substances (TBARS), in the cerebral cortex of CORT-treated mice. The chronic administration of the CHE (100 and 150 mg/Kg) reduced TBARS and the increased total sulfhydryl content, and also reversed the increase in TBARS induced by CORT. In the hippocampus, CORT increased CAT and SOD activities and reduced glutathione peroxidase (GSH-Px) (C) activity, while Myrcia pubipetala Miq. CHE (100 and 150 mg/Kg) increased GSH-Px activity when administered alone and reversed decreased GSH-Px (100 and 150 mg/Kg) activity when given during CORT administration. Neither CORT administration nor CHE treatment significantly altered the immobility time of the animals in FST and no changes were observed in the locomotor activity of the animals in the OFT. Findings indicate that the CHE of Myrcia pubipetala Miq. exerts antioxidant effects in the cerebral cortex and hippocampus of mice induced to depression by CORT. Since phenolic compounds are reported to have antioxidant effects in this species, the effects of the CHE may be, at least in part, mediated by the presence of these compounds in Myrcia extract.

The role of serotonergic and catecholaminergic systems for possible antidepressant activity of apigenin

Background and objective

Although, the anti-depressant like effects of apigenin (APG) are documented in the literature, the underlying mechanism for exerting such an effect is still not clear. In this research, an attempt was made to determine the possible role of APG for antidepressant activity through serotonergic and catecholaminergic systems using standardized animal models.

Materials and methods

The antidepressant property of APG was determine by involving tail suspension (TST) and modified forced swimming tests (MFST). The effect of APG was evaluated at 25 and 50 mg/kg. In mechanistic models, animals were pretreated with catecholaminergic and serotonergic antagonists prior to administration of APG. The results obtained were statistically analyzed to determine the level of significance.

Results

The period of immobility in both models (TST and MFST) was significantly reduced by APG (25 and 50 mg/kg). The best therapetuic dose of APG (50 mg/kg) was selected for the mechanistic study. The anti-immobility effect of APG declined to a significant extent upon pretreatment with catecholaminergic antagonists (α-methyl-para-tyrosine methyl ester; SCH 23390; sulpiride; phentolamine) and serotonergic inhibitors (p-clorophenylalanine-methyl-ester; ondansetron) in both TST and MFST models. The antidepressant benefits of apigenin were only modestly reversed when rats were given propranolol.

Conclusions

The findings suggest that APG's antidepressant effect is mediated by the α-adrenergic, dopaminergic and 5-HT3 serotonergic receptors.

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.

A low-dose combination of ketamine and guanosine counteracts corticosterone-induced depressive-like behavior and hippocampal synaptic impairments via mTORC1 signaling

Ketamine exhibits rapid and sustained antidepressant responses, but its repeated use may cause adverse effects. Augmentation strategies have been postulated to be useful for the management/reduction of ketamine's dose and its adverse effects. Based on the studies that have suggested that ketamine and guanosine may share overlapping mechanisms of action, the present study investigated the antidepressant-like effect of subthreshold doses of ketamine and guanosine in mice subjected to repeated administration of corticosterone (CORT) and the role of mTORC1 signaling for this effect. The ability of the treatment with ketamine (0.1 mg/kg, i.p.) plus guanosine (0.01 mg/kg, p.o.) to counteract the depressive-like behavior induced by CORT (20 mg/kg, p.o., for 21 days) in mice, was paralleled with the prevention of the CORT-induced reduction on BDNF levels, Akt (Ser⁴⁷³) and GSK-3β (Ser⁹) phosphorylation, and PSD-95, GluA1, and synapsin immunocontent in the hippocampus. No changes on mTORC1 and p70S6K immunocontent were found in the hippocampus and prefrontal cortex of any experimental group. No alterations on BDNF, Akt/GSK-3β, mTORC1/p70S6K, and synaptic proteins were observed in the prefrontal cortex of mice. The antidepressant-like and pro-synaptogenic effects elicited by ketamine plus guanosine were abolished by the pretreatment with rapamycin (0.2 nmol/site, i.c.v., a selective mTORC1 inhibitor). Our results showed that the combined administration of ketamine and guanosine at low doses counteracted CORT-induced depressive-like behavior and synaptogenic disturbances by activating mTORC1 signaling. This study supports the notion that the combined administration of guanosine and ketamine may be a useful therapeutic strategy for the management of MDD.

Plant-Derived Compounds as Promising Therapeutics for Vitiligo

Vitiligo is the most common depigmenting disorder characterized by white patches in the skin. The pathogenetic origin of vitiligo revolves around autoimmune destruction of melanocytes in which, for instance, oxidative stress is responsible for melanocyte molecular, organelle dysfunction and melanocyte specific antigen exposure as well as melanocyte cell death and thus serves as an important contributor for vitiligo progression. In recent years, natural products have shown a wide range of pharmacological bioactivities against many skin diseases, and this review focuses on the effects and mechanisms of natural compounds against vitiligo models. It is showed that some natural compounds such as flavonoids, phenols, glycosides and coumarins have a protective role in melanocytes and thereby arrest the depigmentation, and, additionally, Nrf2/HO-1, MAPK, JAK/STAT, cAMP/PKA, and Wnt/β-catenin signaling pathways were reported to be implicated in these protective effects. This review discusses the great potential of plant derived natural products as anti-vitiligo agents, as well as the future directions to explore.

Emerging Role of Flavonoids as the Treatment of Depression

Depression is one of the most frequently observed psychological disorders, affecting thoughts, feelings, behavior and a sense of well-being in person. As per the WHO, it is projected to be the primitive cause of various other diseases by 2030. Clinically, depression is treated by various types of synthetic medicines that have several limitations such as side-effects, slow-onset action, poor remission and response rates due to complicated pathophysiology involved with depression. Further, clinically, patients cannot be given the treatment unless it affects adversely the job or family. In addition, synthetic drugs are usually single targeted drugs. Unlike synthetic medicaments, there are many plants that have flavonoids and producing action on multiple molecular targets and exhibit anti-depressant action by affecting multiple neuronal transmissions or pathways such as noradrenergic, serotonergic, GABAnergic and dopaminergic; inhibition of monoamine oxidase and tropomyosin receptor kinase B; simultaneous increase in nerve growth and brain-derived neurotrophic factors. Such herbal drugs with flavonoids are likely to be useful in patients with sub-clinical depression. This review is an attempt to analyze pre-clinical studies, structural activity relationship and characteristics of reported isolated flavonoids, which may be considered for clinical trials for the development of therapeutically useful antidepressant.

Sex-Specific Social Effects on Depression-Related Behavioral Phenotypes in Mice

Social interaction and empathy play critical roles in determining the emotional well-being of humans. Stress-related depression and anxiety can be exacerbated or mitigated depending on specific social conditions. Although rodents are well known to exhibit emotional contagion and consolation behavior, the effects of group housing on stress-induced phenotypes in both males and females are not well established. Here, we investigated how the presence of stressed or unstressed conspecifics within a cage impact depression-related phenotypes. We housed male and female C57BL/6J mice in same-sex groups and subjected them to either gentle handling (GH) or the daily administration of corticosterone (CORT) for 10 days. The GH and CORT treatment groups were divided into cages of unmixed (GH or CORT) and mixed (GH and CORT) treatments. Depression-related phenotypes were measured using the forced swim test (FST) and sucrose preference test (SPT). We found that mixed housing alters FST behavior in a sex-specific manner. Male mice given chronic corticosterone (CORT) that were housed in the same cage as gently handled animals (GH) exhibited increased immobility, whereas GH females housed with CORT females demonstrated the opposite effect. This study underscores the importance of social housing conditions when evaluating stress-induced behavioral phenotypes and suggests that mixed cages of GH and CORT animals yield the greatest difference between treatment groups. The latter finding has important implications for identifying therapeutics capable of rescuing stress-induced behavioral deficits in the FST.

Neuroprotective Effect of Apigenin on Depressive-Like Behavior: Mechanistic Approach

Apigenin, as a natural flavonoid present in several plants is characterized with potential anticancer, antioxidant, and anti-inflammatory properties. Recent studies proposed that apigenin affects depression disorder through unknown mechanistic pathways. The effects of apigenin's anti-depressive properties on streptozocin-mediated depression have been investigated through the evaluation of behavioral tests, oxidative stress, cellular energy homeostasis and inflammatory responses. The results demonstrated anti-depressive properties of apigenin in behavioral test including forced swimming and splash tests and oxidative stress biomarkers such as reduced glutathione, lipid peroxidation, total antioxidant power and coenzyme Q₁₀ levels. Apigenin, also, demonstrated its regulatory potency in cellular energy homeostasis and immune system gene expression through inhibiting Nlrp3 and Tlr4 overexpression. Furthermore, failure in energy production as the key factor in various psychiatric disorders was reversed by apigenin modulating effect on AMPK gene expression. Overall, 20 mg/kg of apigenin was recognized as the dose suitable for minimizing the undesirable adverse effects in the STZ-mediated depression model proposed in this study. Our data suggested that apigenin could be able to adjust behavioral dysfunction, biochemical biomarkers and recovered cellular antioxidant level in depressed animals. The surprising results were achieved by raise in COQ₁₀ level, which could regulate the overexpression of the AMPK gene in stressful conditions. The regulatory effect of apigenin in inflammatory signaling pathways such as Nlrp3, and Tlr4 gene expression was studied at the surface part of the hippocampus.

Antidepressant effect of catalpol on corticosterone-induced depressive-like behavior involves the inhibition of HPA axis hyperactivity, central inflammation and oxidative damage probably via dual regulation of NF-κB and Nrf2

This study aimed to investigate the antidepressant effect and mechanism of catalpol on corticosterone (CORT)-induced depressive-like behavior in mice for the first time. As a result, CORT injection induced depressive-like behaviors of mice in behavioral tests, aggravated the serum CORT, adrenocorticotropic hormone, and corticotropin-releasing hormone levels, and conspicuously elevated the phosphorylations of nuclear factor kappa-B (NF-κB) in the hippocampus and frontal cortex, and down-regulated the expression levels of nuclear factor erythroid-2-related factor 2 (Nrf2). Furthermore, CORT exposure dramatically augmented the levels of inflammatory factors (interleukin-1β, tumor necrosis factor-α, nitric oxide synthase, and nitric oxide) and lipid peroxidation product malondialdehyde, and attenuated the levels of antioxidants including reduced glutathione, glutathione S-transferase, total superoxide dismutase, and heme oxygenase-1 in the mouse hippocampus and frontal cortex. On the contrary, catalpol administration markedly suppressed the abnormalities of the above indicators. From the overall results, this study displayed that catalpol exerted a beneficial effect on CORT-induced depressive-like behavior in mice possibly via the inhibition of hypothalamus-pituitary-adrenal (HPA) axis hyperactivity, central inflammation and oxidative damage at least partially through dual regulation of NF-κB and Nrf2.

Modulation of Brain-Derived Neurotrophic Factor (BDNF) Signaling Pathway by Culinary Sage (Salvia officinalis L.)

Culinary sage (Salvia officinalis L.) is a common spice plant in the mint family (Lamiaceae) well known for its distinctive culinary and traditional medicinal uses. Sage tea has been used traditionally as a brain-enhancing tonic and extracts from sage have been reported to have both cognitive and memory enhancing effects. Brain-derived neurotrophic factor (BDNF) is an endogenous signaling molecule involved in cognition and memory function. In this study, activity-guided fractionation employing preparative reverse-phase high performance liquid chromatography (RP-HPLC) of culinary sage extracts led to the discovery of benzyl 6-O-β-D-apiofuranosyl-β-D-glucoside (B6AG) as a natural product that upregulates transcription of neurotrophic factors in C6 glioma cells. Purified B6AG showed a moderate dose response, with upregulation of BDNF and with EC₅₀ at 6.46 μM. To better understand the natural variation in culinary sage, B6AG was quantitated in the leaves of several commercial varieties by liquid chromatography-mass spectrometry (LC-MS). The level of B6AG in dried culinary sage was found to range from 334 ± 14 to 698 ± 65 μg/g. This study provided a foundation for future investigations, including quantitative inquiries on the distribution of B6AG within the different plant organs, explorations in optimizing post-harvest practices, and aid in the development of sage varieties with elevated levels of B6AG.

Evidence for 5-HT1A receptor-mediated antiallodynic and antihyperalgesic effects of apigenin in mice suffering from mononeuropathy

BACKGROUND AND PURPOSE

Neuropathic pain places a devastating health burden, with very few effective therapies. We investigated the potential antiallodynic and antihyperalgesic effects of apigenin, a natural flavonoid with momoamine oxidase (MAO) inhibitory activity, against neuropathic pain and investigated the mechanism(s).

EXPERIMENTAL APPROACH

The neuropathic pain model was produced by chronic constriction injury of sciatic nerves in male C57BL/6J mice, with pain-related behaviours being assayed by von Frey test and Hargreaves test. In this model the role of 5-HT and 5-HT_1A receptor-related mechanisms were investigated in vivo/in vitro.

KEY RESULTS

Apigenin repeated treatment (p.o., once per day for 2 weeks), in a dose-related manner (3, 10 and 30 mg·kg^-1 ), ameliorated the allodynia and hyperalgesia in chronic nerve constriction injury in mice. These effects seem dependent on neuronal 5-hydroxytryptamine, because (i) the antihyperalgesia and antiallodynia were attenuated by depletion of 5-HT with p-chlorophenylalanine and potentiated by 5-hydroxytryptophan and (ii), apigenin-treated chronic constriction injury mice caused an increased level of spinal 5-HT, associated with diminished MAO activity. In vivo administration, spinally or systematically, of the 5-HT_1A antagonist WAY-100635 inhibited the apigenin-induced antiallodynia and antihyperalgesia. In vitro, apigenin acted as a positive allosteric modulator to increase the efficacy (stimulation of [³⁵ S]GTPγS binding) of the 5-HT_1A agonist 8-OH-DPAT. Apigenin attenuated neuronal changes caused by chronic constriction of the sciatic nerve in mice, without causing a hypertensive crisis.

CONCLUSION AND IMPLICATIONS

Apigenin antiallodynic and antihyperalgesic actions against neuropathic pain crucially involve spinal 5-HT_1A receptors and indicate it could be used to treat neuropathic pain.

Pharmacogenetic-based management of depression: Role of traditional Persian medicine

Depression is one of the most common mental disorders worldwide. The genetic factors are linked to depression and anti-depressant outcomes. Traditional Persian medicine (TPM) manuscripts have provided various anti-depressant remedies, which may be useful in depression management. This review has studied the bioactive compounds, underlying mechanisms, and treatment outcomes of the medicinal plants traditionally mentioned effective for depression from "The storehouse of medicament" (a famous pharmacopeia of TPM) to merge those with the novel genetics science and serve new scope in depression prevention and management. This review paper has been conducted in two sections: (1) Collecting medicinal plants and their bioactive components from "The storehouse of medicament," "Physician's Desk Reference (PDR) for Herbal Medicines," and "Google scholar" database. (2) The critical key factors and genes in depression pathophysiology, prevention, and treatment were clarified. Subsequently, the association between bioactive components' underlying mechanism and depression treatment outcomes via considering polymorphisms in related genes was derived. Taken together, α-Mangostin, β-carotene, β-pinene, apigenin, caffeic acid, catechin, chlorogenic acid, citral, ellagic acid, esculetin, ferulic acid, gallic acid, gentiopicroside, hyperoside, kaempferol, limonene, linalool, lycopene, naringin, protocatechuic acid, quercetin, resveratrol, rosmarinic acid, and umbelliferone are suitable for future pharmacogenetics-based studies in the management of depression.

LC-MS/MS Determination of Apigenin in Rat Plasma and Application to Pharmacokinetic Study

BACKGROUND

Apigenin, a natural plant flavone, has been shown to possess a variety of biological properties.

OBJECTIVE

In this report, a highly selective and sensitive LC-MS/MS method was developed and validated for the determination of apigenin in rat plasma.

METHODS

Analysts were separated on the HSS T3 column (1.8 μm 2.1×100 mm) using acetonitrile and 0.1% formic acid in 2mM ammonium acetate buffer at a supply rate of 0.200 mL/min as eluent in gradient model.

RESULTS

Plasma samples were treated by protein precipitation using acetonitrile for the recovery ranging from 86.5% to 90.1% for apigenin. The calibration curves followed linearity in the concentration range of 0.50-500ng/mL. The inter-day and intra-day precisions at different QC levels within 13.1% and the accuracies ranged from -10.6% to 8.6%.

CONCLUSION

The assay has been successfully applied to the pharmacokinetic study of apigenin in rats.

Protocatechuic acid attenuates chronic unpredictable mild stress induced-behavioral and biochemical alterations in mice

Amelioration of oxidative stress via promoting the endogenous antioxidant system and enhancement of monoamines in brain were the important underlying antidepressant mechanism of protocatechuic acid (PCA). The aim of the present study is to explore the potential antidepressant mechanism(s) PCA in chronic unpredictable mild stress (CUMS) mice. Mice were subjected to CUMS protocol for 4 weeks, and administered with PCA (100 and 200 mg/kg) and fluoxetine (20 mg/kg) for 24 days (from day 8th to 31st). Behavioral (sucrose preference, immobility time, exploratory behavior), and biochemical alterations such as serum corticosterone, brain derived neurotrophic factor (BDNF), inflammatory cytokines, tumor necrosis factor- α (TNF-α), interleukin-6 (IL-6), and antioxidants parameters were investigated. Experimental findings revealed that CUMS subjected mice exhibited significant impairment in behavioral alterations, such as increased immobility time, impaired preference to the sucrose solution, BDNF levels and, serum corticosterone, cytokines, malondialdehyde (MDA) formation with impaired antioxidants in the hippocampus and cerebral cortex. Administration of PCA to CUMS mice attenuated the immobility time, serum corticosterone, cytokines TNF-α, and IL-6, MDA formation and improved sucrose preference, including restoration of BDNF level. Thus, the present findings demonstrated the antidepressant potential of PCA which is largely achieved probably through maintaining BDNF level, and by modulation of the oxidative stress response, cytokines systems, and antioxidant defense system in mice.

Enriched Environment Minimizes Anxiety/Depressive-Like Behavior in Rats Exposed to Immobilization Stress and Augments Hippocampal Neurogenesis (In Vitro)

Chronic exposure to stress disturbs the homeostasis of the brain, thus, deleteriously affecting the neurological circuits. In literature, there are investigations about the stress-related alterations in behavioral response and adult neurogenesis; however, an effective combating strategy to evade stress is still at stake. Hence, the present study is designed to investigate the effect of an enriched environment in alleviating the anxiety/depressive-like behavioral response and enhancing the adult neurogenesis in the hippocampal region of rats exposed to chronic immobilization stress. The rats were exposed to chronic immobilization stress (IS) for 4 h/day followed by the enriched environment (EE) for 2 h/day for 28 days, and finally, the hippocampal region was dissected out after the behavioral analyses. IS group showed increased behavioral despair to tail suspension test, decrement in the activity for light/dark box test, and less grooming activity towards splash test. In contrast, IS + EE rats exhibited a decrease in the activity of tail suspension test and an increase in the behavioral response to light/dark box test and splash test. The in vitro assessment of primary cultures of neurospheres from the IS group resulted in decreased levels of proliferation in the cell number and metabolic activity of both MTT assay and lactate levels. IS + EE group revealed an increase in the growth curve of neurospheres and higher metabolic activities of MTT and lactate. The IS cultures had reduced neurite length, while the neurite outgrowths were increased in IS + EE group. The IS group showed significant reduction in the protein and mRNA levels of nestin, GFAP, CD11b, MOG, and synaptophysin, whereas the IS + EE cultures exhibited significant increase in the levels of these stem cell markers. Our data highlight the positive impact of EE against stress-related behavioral changes in rats exposed to chronic immobilization stress perhaps by interfering with the differentiation of neurospheres and neurogenesis.

Animal Models of Depression: What Can They Teach Us about the Human Disease?

Depression is apparently the most common psychiatric disease among the mood disorders affecting about 10% of the adult population. The etiology and pathogenesis of depression are still poorly understood. Hence, as for most human diseases, animal models can help us understand the pathogenesis of depression and, more importantly, may facilitate the search for therapy. In this review we first describe the more common tests used for the evaluation of depressive-like symptoms in rodents. Then we describe different models of depression and discuss their strengths and weaknesses. These models can be divided into several categories: genetic models, models induced by mental acute and chronic stressful situations caused by environmental manipulations (i.e., learned helplessness in rats/mice), models induced by changes in brain neuro-transmitters or by specific brain injuries and models induced by pharmacological tools. In spite of the fact that none of the models completely resembles human depression, most animal models are relevant since they mimic many of the features observed in the human situation and may serve as a powerful tool for the study of the etiology, pathogenesis and treatment of depression, especially since only few patients respond to acute treatment. Relevance increases by the fact that human depression also has different facets and many possible etiologies and therapies.

Animal models of major depression: drawbacks and challenges

Major depression is a leading contributor to the global burden of disease. This situation is mainly related to the chronicity and/or recurrence of the disorder, and to poor response to antidepressant therapy. Progress in this area requires valid animal models. Current models are based either on manipulating the environment to which rodents are exposed (during the developmental period or adulthood) or biological underpinnings (i.e. gene deletion or overexpression of candidate genes, targeted lesions of brain areas, optogenetic control of specific neuronal populations, etc.). These manipulations can alter specific behavioural and biological outcomes that can be related to different symptomatic and pathophysiological dimensions of major depression. However, animal models of major depression display substantial shortcomings that contribute to the lack of innovative pharmacological approaches in recent decades and which hamper our capabilities to investigate treatment-resistant depression. Here, we discuss the validity of these models, review putative models of treatment-resistant depression, major depression subtypes and recurrent depression. Furthermore, we identify future challenges regarding new paradigms such as those proposing dimensional rather than categorical approaches to depression.

The antidepressant effects of apigenin are associated with the promotion of autophagy via the mTOR/AMPK/ULK1 pathway

The present study aimed to investigate whether apigenin elicits antidepressant effects in depressant‑like mice via the regulation of autophagy. The depressant‑like behaviors were established in a chronic restraint stress model. Male BALB/c mice were subjected to restraint stress for 6 h/day for a period of 21 days, and deficits in sucrose preference, tail suspension and forced swim tests were confirmed to be improved following oral apigenin. To investigate the underlining mechanisms, the hippocampal levels of p62 and microtubule‑associated protein light chain 3‑II/I (LC3‑II/I) were measured using western blot analysis. The expression levels of LC3‑II/I and p62 indicated that the significantly inhibited autophagy level induced by chronic restraint stress can be increased following apigenin treatment. Similar to the level of autophagy, the expression levels of adenosine monophosphate‑activated protein kinase (AMPK) and Unc‑51 like autophagy activating kinase‑1 were downregulated after chronic restraint stress stimulation and, subsequently upregulated following treatment with apigenin. Conversely, the levels of mammalian target of rapamycin (mTOR) were increased in chronic restraint stress mice and inhibited by apigenin. Collectively, the present findings indicated that apigenin potentially promotes autophagy via the AMPK/mTOR pathway and induces antidepressive effects in chronic restraint stress mice.

Assessment of Antidepressant Effect of the Aerial Parts of Micromeria myrtifolia Boiss. & Hohen on Mice

The currently available antidepressant agents necessitate the development of newer alternatives because of their serious adverse effects and costs. Traditional medicinal knowledge is likely the key that opens the door to discover new medicines. In Turkish folk medicine, the infusion prepared from aerial parts of Micromeria myrtifolia Boiss. & Hohen is used as pleasure and medicinal tea for its relaxing action. The present research was conceived to confirm the antidepressant’s potential of this traditional medicinal plant. In this process, first of all, the collected and shade-dried aerial parts of M. myrtifolia were powdered and then, extracted using solvents with different polarity as follows; n-hexane, ethyl acetate (EtOAc), and methanol (MeOH). The antidepressant activity of the extracts was evaluated by using several in vivo and in vitro experimental models of depression. When the data obtained from the control and experimental groups were compared, it was determined that the MeOH extract was the most active. The active components of this extract were isolated and identified utilizing various chromatographic separation techniques. The MeOH extract was applied to reversed phase (RP-18) column chromatography to obtain five main fractions and they were tested on antidepressant activity models. The isolated compounds from the obtained fractions were elucidated as rosmarinic acid (1), myricetin (2), apigenin (3), and naringenin (4) which were assumed to be responsible for the antidepressant activity of the aerial parts. According to the results, rosmarinic acid, myricetin, apigenin, and naringenin showed statistically significant activity on forced swimming test and tetrabenazine-induced ptosis models, whereas only rosmarinic acid showed statistically significant activity on the tail suspension test. Apigenin displayed the highest inhibitory activity on MAO A and B enzymes. Studies in the future should be performed to investigate the antidepressant activity mechanism of these natural compounds. The current research could be an important step in the development of the new agents that can be used in the treatment of depression.