Antidepressant-like effects of water extract of Gastrodia elata Blume in rats exposed to unpredictable chronic mild stress via modulation of monoamine regulatory pathways

Neuropharmacological effects of Gastrodia elata Blume and its active ingredients

Gastrodia elata Blume (GE), a traditional Chinese medicine clinically employed to treat neurological disorders, demonstrates therapeutic efficacy supported by robust clinical evidence. Nowadays, conventional pharmacotherapies for neurological conditions-such as cholinesterase inhibitors for Alzheimer's or Ldopa for Parkinson's-often provide limited symptom relief, exhibit side effects, and fail to halt disease w, underscoring the need for alternative strategies. The primary bioactive compounds of Gastrodia elata Blume (GE) include gastrodin, p-hydroxybenzyl alcohol, Vanillyl alcohol, Polysaccharides, and β-sitosterol. Modern research has demonstrated that GE and its active components exhibit neuropharmacological effects, including neuron protection, reduction of neurotoxicity, and promotion of nerve regeneration and survival. For example, Gastrodin, exerts neuroprotection by scavenging reactive oxygen species, suppressing pro-inflammatory cytokines, and enhancing GABAergic transmission, thereby alleviating oxidative stress and neuronal apoptosis. Vanillin, potentiates GABA receptor activity, enhancing inhibitory neurotransmission and reducing seizure susceptibility.GE polysaccharides modulate the gut-brain axis and suppress microglial activation, mitigating neuroinflammation. Current studies primarily focus on GE and its active ingredients for the treatment of neurological diseases such as Parkinson's disease, Alzheimer's disease, epilepsy, convulsions, depression, schizophrenia, as well as enhancing learning and memory, and preventing or treating cerebral ischemic injury. This review explores the neuropharmacological effects of GE and its active compounds, elucidates the underlying mechanisms, and suggests potential preventive and therapeutic strategies for neurological diseases using herbal remedies.

Amino acid metabolites profiling in unpredictable chronic mild stress-induced depressive rats and the protective effects of Gastrodia elata Blume and gastrodin

ETHNOPHARMACOLOGICAL RELEVANCE

Major depressive disorder (MDD) is a prevalent condition that affects approximately 350 million people worldwide. Several studies have identified changes in amino acids in the blood of MDD patients, suggesting their potential as biomarkers to better understand their role in depression. Gastrodia elata Blume (GEB) and its active compound gastrodin (GAS) are recognized for their antidepressant properties. However, their effects on amino acid profiles and their potential role in alleviating depression remain poorly understood. Understanding how GEB and GAS influence amino acid metabolism may offer novel insights into their mechanisms in alleviating depression, potentially leading to more targeted therapeutic strategies.

AIM OF THE STUDY

This study aimed to investigate the potential role of supplementing GEB and its active compound GAS to reverse altered amino acid profiles in depressed rats.

MATERIALS AND METHODS

To achieve this, six-week-old SD rats were induced depressive-like behaviors by the UCMS rat model for 5 weeks. Groups receiving GEB or GAS were administered orally via gavage daily within the UCMS model. Serum samples were collected and analyzed using a targeted metabolomics approach employing LC-MS for amino acid profiling.

RESULTS

A total of 38 amino acid metabolites were identified, 17 of which were significantly altered following UCMS. UCMS rats exhibited perturbed arginine biosynthesis, arginine and proline metabolism pathways. Changes in key amino acids in these metabolic pathways were reversed following supplementation with GEB and GAS, which also alleviated depressive symptoms.

CONCLUSIONS

In conclusion, UCMS-induced depression in rats causes changes in some amino acid metabolites similar to those found in human depression, validating its relevance as a model for studying depression. Additionally, the research suggests that GEB and GAS may exert antidepressant effects by regulating amino acid metabolism.

Cordyceps militaris and Armillaria mellea formula alleviates depressive behaviors via microglia regulation in an unpredictable chronic mild stress animal model

Background and aim

Cordyceps militaris (CM) and Armillaria mellea (AM) are medicinal mushrooms with potential applications in the treatment of mood disorders, including depression and anxiety. While research suggests that both CM and AM possess anti-inflammatory properties and hold potential for treating depression when administered separately, there is limited knowledge about their efficacy when combined in a formula, as well as the underlying mechanism involving the modulation of microglia.

Experimental procedure

Rats received oral administrations of the low-dose formulation, medium-dose formulation, and high-dose formulation over 28 consecutive days as part of the UCMS protocols. The concentrations of serotonin, dopamine, and the corresponding metabolites in the rat prefrontal cortex and hippocampus were assessed. Blood samples were collected to examine corticosterone levels, and the brains were dissected for evaluating activated microglia morphologies and associated pro- and anti-inflammatory signaling pathways.

Results and conclusion

The CM-AM formula effectively averted abnormal behaviors triggered by UCMS, such as anhedonia and hypoactivity, and decreased the turnover rate of monoamines in both the prefrontal cortex and hippocampus. The formula mitigated the increase in serum corticosterone levels induced by chronic stress. Furthermore, the formula alleviated stress-induced microglia activation in the hippocampus, achieving this by down-regulating hyperactivated pro-inflammatory proteins and up-regulating hypoactivated anti-inflammatory proteins in the hippocampus. The antidepressant-like effects potentially stemming from the regulation of neurotransmitters and immunomodulation, likely by restoring the balance of M1 and M2 microglia fractions in the hippocampus. Consequently, the CM-AM formula could be explored as a prospective complementary and alternative therapy for depression.

A Review of Gastrodia Elata Bl.: Extraction, Analysis and Application of Functional Food

Gastrodia elata Bl. still widely known as a medicinal plant due to its anti-inflammatory, neuroprotection, cardiovascular protection etc. Additionally, these medical applications cannot be separated from its antioxidant, anti-aging, regulating cell apoptosis ability, which make it have potential as a functional food as well as it has been eaten for more than 2,000 years in China. At present, although Gastrodia elata Bl. has appeared in a large number of studies, much of the research is based on drugs rather than foods. The review of Gastrodia elata Bl. from the perspective of food is one of the necessary steps to promote related development, by reviewing the literature on analytical methods of Gastrodia elata Bl. in recent years, critical components change in the extraction, analytical methods and improvement of food applications, all of aspects of it was summarized. Based on the report about physical and chemical changes in Gastrodia elata Bl. to discover the pathway of Gastrodia elata Bl. functional food development from current to the future.

Biology of Callistethus plagiicollis (Coleoptera: Scarabaeoidea: Rutelinae) and comparative morphology of its larvae

Larvae of the beetle subfamily Rutelinae are poorly described in the literature. Notably, the morphology of the larvae of Callistethus plagiicollis Fairmaire has not previously been analyzed. Here, we report for the first time that these larvae feed on the tubers and roots of Gastrodia elata Blume, an important traditional Chinese herbal medicine, which causes a reduction in the yield and economic value of G. elata. We employed scanning electron microscopy and light microscopy to investigate the morphology and occurrence regularity of egg, larvae, pupae, and adult specimens of C. plagiicollis collected from the G. elata planting base in Guizhou Province, China, with a focus on the ultrastructure of mature larvae. The results revealed one generation of C. plagiicollis per year in the study area and three instar stages of larvae. Mature larvae were identified by the following characteristics: raster without palidia with a large number of hamate setae, antennal apex containing seven sensilla basiconica, larval haptomerum containing eight sensilla styloconica and four enlarged heli, and seven longitudinally arranged stridulatory teeth on the stipes of the maxilla. The combination of scanning electron and light microscopy effectively revealed the difference between membranous and sclerotized structures, ensuring accurate identification of C. plagiicollis larvae. By determining the feeding characteristics and occurrence regularity of C. plagiicollis, this study has implications for improved pest management in G. elata crops. RESEARCH HIGHLIGHTS: We identified C. plagiicollis as a new pest of G. elata, a traditional Chinese medicine Scanning electron and light microscopy were combined to analyze the morphology of the mature larvae of C. plagiicollis for the first time We determined the feeding characteristics and occurrence regularity of C. plagiicollis, which can be used to develop effective pest management strategies.

Gastrodin alleviates the deterioration of depressive-like behavior and glucolipid metabolism promoted by chronic stress in type 2 diabetic mice

The growing burden of psychological stress among diabetes patients has contributed to a rising incidence of depression within this population. It is of significant importance to conduct research on the impact of stress on diabetes patients and to explore potential pharmacological interventions to counteract the stress-induced exacerbation of their condition. Gastrodin is a low molecular weight bioactive compound extracted from the rhizome of Gastrodiae elata Blume, and it may be a preventive strategy for diabetes and a novel treatment for depression symptoms. However, its relevant pharmacological mechanisms for protecting against the impacts of psychological stress in diabetic patients are unclear. In this study, we performed 5 weeks CUMS intervention and simultaneously administered gastrodin (140 mg/kg, once daily) on T2DM mice, to investigate the potential protective effects of gastrodin. The protective effect of gastrodin was evaluated by behavioral tests, biochemical analysis, histopathological examination, RT-qPCR and gut microbiota analysis. We found that the depressive-like behavior and glucolipid metabolism could be deteriorated by chronic stress in type 2 diabetic mice, while gastrodin showed a protective effect against these exacerbations by regulating HPA hormones, activating FXR and Cyp7a1, reducing inflammatory and oxidative stress responses, and regulating ileal gut microbiota abundance. Gastrodin might be a potential therapeutic agent for mitigating the deterioration of diabetes conditions due to chronic stress.

Mechanisms for the biological activity of Gastrodia elata Blume and its constituents: A comprehensive review on sedative-hypnotic, and antidepressant properties

BACKGROUND

Insomnia and depressive disorder are two common symptoms with a reciprocal causal relationship in clinical practice, which are usually manifested in comorbid form. Several medications have been widely used in the treatment of insomnia and depression, but most of these drugs show non-negligible side effects. Currently, many treatments are indicated for insomnia and depressive symptom, including Chinese herbal medicine such as Gastrodia elata Blume (G. elata), which has excellent sedative-hypnotic and antidepressant effects in clinical and animal studies.

PURPOSE

To summarize the mechanisms of insomnia and depression and the structure-activity mechanism for G. elata to alleviate these symptoms, particularly by hypothalamic-pituitary-adrenal (HPA) axis and intestinal flora, aiming to discover new approaches for the treatment of insomnia and depression.

METHODS

The following electronic databases were searched from the beginning to November 2023: PubMed, Web of Science, Google Scholar, Wanfang Database, and CNKI. The following keywords of G. elata were used truncated with other relevant topic terms, such as depression, insomnia, antidepressant, sedative-hypnotic, neuroprotection, application, safety, and toxicity.

RESULTS

Natural compounds derived from G. elata could alleviate insomnia and depressive disorder, which is involved in monoamine neurotransmitters, inflammatory response, oxidative stress, and gut microbes, etc. Several clinical trials showed that G. elata-derived natural compounds that treat depression and insomnia have significant and safe therapeutic effects, but further well-designed clinical and toxicological studies are needed.

CONCLUSION

G. elata exerts a critical role in treating depression and insomnia due to its multi-targeting properties and fewer side effects. However, more clinical and toxicological studies should be performed to further explore the sedative-hypnotic and antidepressant mechanisms of G. elata and provide more evidence and recommendations for its clinical application. Our review provides an overview of G. elata treating insomnia with depression for future research direction.

A Novel Variable Selection Method Based on Ordered Predictors Selection and Successive Projections Algorithm for Predicting Gastrodin Content in Fresh Gastrodia elata Using Fourier Transform Near-Infrared Spectroscopy and Chemometrics

Gastrodin is one of the most important biologically active components of Gastrodia elata, which has many health benefits as a dietary and health food supplement. However, gastrodin measurement traditionally relies on laboratory and sophisticated instruments. This research was aimed at developing a rapid and non-destructive method based on Fourier transform near infrared (FT-NIR) to predict gastrodin content in fresh Gastrodia elata. Auto-ordered predictors selection (autoOPS) and successive projections algorithm (SPA) were applied to select the most informative variables related to gastrodin content. Based on that, partial least squares regression (PLSR) and multiple linear regression (MLR) models were compared. The autoOPS-SPA-MLR model showed the best prediction performances, with the determination coefficient of prediction (Rp2), ratio performance deviation (RPD) and range error ratio (RER) values of 0.9712, 5.83 and 27.65, respectively. Consequently, these results indicated that FT-NIRS technique combined with chemometrics could be an efficient tool to rapidly quantify gastrodin in Gastrodia elata and thus facilitate quality control of Gastrodia elata.

Review on pharmacological effects of gastrodin

Gastrodia elata Blume is a well-known traditional Chinese medicine that is mainly used to treat diseases related to the nervous system, such as stroke, epilepsy, and headache. Gastrodin is the main bioactive component of Gastrodia elata Blume, and studies have shown that it has extensive pharmacological activity. This narrative review aims to systematically review relevant studies on the pharmacological effects of gastrodin to provide researchers with the latest and most useful information. Studies have shown that gastrodin has prominent neuroprotective effects and can treat or improve epilepsy, Tourette syndrome, Alzheimer's disease, Parkinson's disease, emotional disorders, cerebral ischemia-reperfusion injury, cognitive impairment, and neuropathic pain. Gastrodin can also improve myocardial hypertrophy, hypertension, and myocardial ischemia-reperfusion injury. In addition, gastrodin can mitigate liver, kidney, and bone tissue damage caused by oxidative stress and inflammation. In short, gastrodin is expected to treat many diseases, and it is worth investing more effort in research on this compound.

Garlic essential oil ameliorates depression-like behaviors in unpredictable chronic mild stress by modulating the brain NLRP3 inflammasome pathway and influencing the gut barrier and microbiota

Depression is a severe mental disorder, with approximately 300 million people suffering from it. Recent studies have demonstrated that chronic neuroinflammation is significantly associated with intestinal flora and barrier function in depression. As a therapeutic herb, garlic (Allium sativum L.) has detoxification, antibacterial activity, and antiinflammatory functions; however, its antidepressant effect through gut microbiota and barrier function has not been reported yet. The present study investigated the effect of garlic essential oil (GEO) and its active constituent diallyl disulfide (DADS) on depressive behavior by attenuating the NLRP3 inflammasome, alternating intestinal barrier function and gut microbiota in an unpredictable chronic mild stress (US) model in rats. This study found that dopamine and serotonin turnover rates were reduced significantly with a low dose of GEO (25 mg per kg bw). The GEO groups effectively reversed sucrose preference and increased the total distance traveled in the behavioral test. Moreover, 25 mg per kg bw GEO inhibited the UCMS-induced activated inflammatory response, reflected by reduced expression in the frontal cortex of NLRP3, ASC, caspase-1, and its downstream IL-1β proteins, as well as the concentration of IL-1β and TNF-α in the serum. Supplementation with GEO increased the expression of occludin and ZO-1 and the concentration of short-chain fatty acids to influence the impact of intestinal permeability in depressive conditions. The results revealed that GEO administration caused significant changes in the α and β diversity and abundance of certain bacteria. At the genus level, GEO administration significantly increased the relative abundance, particularly beneficial SCFA-producing bacteria, and may improve depression-like behavior. In conclusion, these results indicated the antidepressant effects of GEO involved in the inflammatory pathway, short-chain fatty acids, intestinal integrity, and intestinal composition.

The processing methods, phytochemistry and pharmacology of Gastrodia elata Bl.: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Bl. (GE) is one of the rare Chinese medicinal materials with a long history of medicine and cooking. It consists of a variety of chemical components, including aromatic compounds, organic acids and esters, steroids, saccharides and their glycosides, etc., which has medicinal and edible value, and is widely used in various diseases, such as infantile convulsions, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. It is also commonly used in health care products and cosmetics. Thus, its chemical composition and pharmacological activity have attracted more and more attention from the scientific community.

AIM

In this review, the processing methods, phytochemistry and pharmacological activities of GE were comprehensively and systematically summarized, which provides a valuable reference for researchers the rational of GE.

MATERIALS AND METHODS

A comprehensive search of published literature and classic books from 1958 to 2023 was conducted using online bibliographic databases PubMed, Google Scholar, ACS, Science Direct Database, CNKI and others to identify original research related to GE, its processing methods, active ingredients and pharmacological activities.

RESULTS

GE is traditionally used to treat infantile convulsion, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. To date, more than 435 chemical constituents were identified from GE including 276 chemical constituents, 72 volatile components and 87 synthetic compounds, which are the primary bioactive compounds. In addition, there are other biological components, such as organic acids and esters, steroids and adenosines. These extracts have nervous system and cardiovascular and cerebrovascular system activities such as sedative-hypnotic, anticonvulsant, antiepileptic, neuron protection and regeneration, analgesia, antidepressant, antihypertensive, antidiabetic, antiplatelet aggregation, anti-inflammatory, etc. CONCLUSION: This review summarizes the processing methods, chemical composition, pharmacological activities, and molecular mechanism of GE over the last 66 years, which provides a valuable reference for researchers to understand its research status and applications.

Anti-depressive-like and cognitive impairment alleviation effects of Gastrodia elata Blume water extract is related to gut microbiome remodeling in ApoE-/- mice exposed to unpredictable chronic mild stress

ETHNOPHARMACOLOGY RELEVANCE

Gastrodia elata Blume (GE) is a traditional Chinese dietary therapy used to treat neurological disorders. Gastrodia elata Blume water extract (WGE) has been shown to ameliorate inflammation and improve social frustration in mice in a chronic social defeat model. However, studies on the anti-depressive-like effects and cognitive impairment alleviation related to the impact of WGE on the gut microbiome of ApoE-/- mice remain elusive.

AIM OF THE STUDY

The present study aimed to investigate the anti-depressive-like effect and cognitive impairment alleviation and mechanisms of WGE in ApoE-/- mice subjected to unpredictable chronic mild stress (UCMS), as well as its impact on the gut microbiome of the mice.

MATERIALS AND METHODS

Sixty ApoE-/- mice (6 months old) were randomly grouped into six groups: control, UCMS, WGE groups [5, 10, 20 mL WGE/kg body weight (bw) + UCMS], and a positive group (fluoxetine 20 mg/kg bw + UCMS). After four weeks of the UCMS paradigm, the sucrose preference, novel object recognition, and open field tests were conducted. The neurotransmitters serotonin (5-HT), dopamine (DA) and their metabolites were measured in the prefrontal cortex. Serum was collected to measure corticosterone and amyloid-42 (Aβ-42) levels. Feces were collected, and the gut microbiome was analyzed.

RESULTS

WGE restored sucrose preference, exploratory behavior, recognition ability, and decreased the levels of serum corticosterone and Aβ-42 in ApoE-/- mice to alleviate depressive-like behavior and cognitive impairment. Furthermore, WGE regulated the monoamine neurotransmitter via reduced the 5-HT and DA turnover rates in the prefrontal cortex. Moreover, WGE elevated the levels of potentially beneficial bacteria such as Bifidobacterium, Akkermansia, Alloprevotella, Defluviitaleaceae_UCG-011, and Bifidobacterium pseudolongum as well as balanced fecal short-chain fatty acids (SCFAs).

CONCLUSION

WGE demonstrates anti-depressive-like effects, cognitive impairment alleviation, and gut microbiome and metabolite regulation in ApoE-/- mice. Our results support the possibility of developing a functional and complementary medicine to prevent or alleviate depression and cognitive decline using WGE in CVDs patients.

A Review of Antidepressant Effects and Mechanisms of Three Common Herbal Medicines: Panax ginseng, Bupleurum chinense, and Gastrodia elata

OBJECTIVES

Major depressive disorder (MDD) has been reported to affect an increasing number of individuals due to the modern lifestyle. Because of its complicated mechanisms and recurrent attacks, MDD is considered a refractory chronic disease. Although the mainstream therapy for MDD is chemical drugs, they are not a panacea for MDD because of their expensiveness, associated serious adverse reactions, and endless treatment courses. Hence, we studied three kinds of herbal medicines, namely, Panax ginseng C.A. Mey (PGM), Bupleurum chinense DC (BCD), and Gastrodia elata Blume (GEB), and reviewed the mechanisms underlying their antidepressant properties to provide a reference for the development of antidepressants and clinical medications.

METHODS

An extensive range of medicinal, clinical, and chemistry databases and search engines were used for our literature search. We searched the literature using certain web literature search engines, including Google Scholar, PubMed, Science Direct, CNKI (China National Knowledge Infrastructure), and Web of Science.

RESULTS

Experimental research found that active compounds of these three medicines exhibited good antidepressant effects in vivo and in vitro. Clinical investigations revealed that single or combined treatment of these medicines improved certain depressive symptoms. Antidepressant mechanisms are summarized based on this research.

CONCLUSION

The antidepressant mechanism of these three medicines includes but is not limited to ameliorating inflammation within the brain, reversing the hypothalamic-pituitary adrenal axis (HPA) system hyperfunction, inhibiting monoamine neurotransmitters reuptake, anti-neuron apoptosis and preventing neurotoxicity, and regulating depressive-related pathways such as the BDNF pathway and the PI3K/Akt/mTOR pathway.

Methanolic Extract of Aerva javanica Leaves Prevents LPS-Induced Depressive Like Behavior in Experimental Mice

Aim

Depression is a chronic recurrent neuropsychiatric disorder associated with inflammation. This study explored the pharmacological activities of Aerva javanica leaves crude extract (Aj.Cr) on lipopolysaccharide (LPS)-induced depressive-like behavior in experimental mice.

Methods

Aj.Cr was evaluated for its phenolic and flavonoid contents, bioactive potential, amino acid profiling and enzyme inhibition assays using different analytical techniques followed by in-silico molecular docking was performed. In addition, three ligands identified in HPLC analysis and standard galantamine were docked to acetyl cholinesterase (AchE) enzyme to assess the ligand interaction along with their binding affinities. In in-vivo analysis, mice were given normal saline (10 mL/kg), imipramine (10 mg/kg) and Aj.Cr (100, 300, and 500 mg/kg) orally for 14-consecutive days. On the 14th day, respective treatment was given 30-minutes before intra-peritoneal administration of (0.83 mg/kg) LPS. Open field, forced swim and tail suspension tests were performed 24-hours after LPS injection, followed by a sucrose preference test 48-hours later. Serum corticosterone levels, as well as levels of nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-alpha (TNF-), interleukin-1β (IL-1β), interleukin-6 (IL-6), brain-derived neurotrophic factor (BDNF) and catecholamines were determined in brain tissues.

Results

In-vitro results revealed that crude extract of Aj.Cr possesses anti-depressant agents with solid antioxidant potential. In-vivo analysis showed that LPS significantly increased depressive-like behavior followed by alteration in serum and tissue biomarkers as compared to normal control (p < 0.001). While imipramine and Aj.Cr (100, 300, and 500 mg/kg) treated groups significantly (p<0.05) improved the depressive-like behavior and biomarkers when compared to the LPS group.

Conclusion

The mitigation of LPS-induced depressive-like behavior by Aj.Cr may be linked to the modulation of oxidative stress, neuro-inflammation and catecholamines due to the presence of potent bioactive compounds exerting anti-depressant effects.

Neuroprotection of Gastrodia elata polyphenols against H2O2-induced PC12 cell cytotoxicity by reducing oxidative stress

It has been suggested that oxidative stress (OS) has a role in the development of aging and neurodegenerative disorders. Biological molecules are easily damaged by reactive oxygen species, which can ultimately result in necrotic or apoptotic cell death. Foods containing phytochemicals, such as phenolic compounds, may have potential preventive effects against several diseases, including alzheimer's disease (AD), according to epidemiological and in vitro research. Gastrodia elata is a well-known homology of medicine and food plant that has been used for centuries in China and other East Asian countries to treat central nervous system disorders. In this study, we focused on the potential of the extract, Gastrodia elata polyphenols (GPP), for the prevention and treatment of AD. H2O2 induced PC12 cell damage was used to simulate the oxidative stress of AD. The effects of GPP on the injury model were evaluated by cell survival rate, lactate dehydrogenase (LDH), lipid peroxidation (MDA), production of intracellular antioxidant enzymes, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), cellular inflammation level and apoptosis level. The results showed that GPP pretreatment had a protective effect by increasing cell viability, reducing lactate dehydrogenase infiltration, decreasing MDA and increasing intracellular antioxidant enzymes, diminishing reactive oxygen species production and decreasing mitochondrial membrane potential, reducing cell inflammation and decreasing apoptosis. Accordingly, it is suggested that GPP possessed promising neuroprotective benefits which enabled the prevention or therapeutic implementation of AD along with serving as a reference towards the exploitation of functional foods or drugs derived from Gastrodia elata.

Diagnosis and Drug Prediction of Parkinson's Disease Based on Immune-Related Genes

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Immune mechanisms play an important role in the development of PD. The purpose of this study was to identify potential differentially expressed immune-related genes (IRGs), signaling pathways, and drugs in PD, which may provide new diagnostic markers and therapeutic targets for PD. Differentially expressed genes (DEGs) and IRGs were respectively obtained from the Gene Expression Omnibus (GEO) dataset and the ImmPort database. Weighted gene co-expression network analysis (WGCNA) was utilized to further identify hub IRGs. Core IRGs were obtained by intersection of DEGs and hub genes in the module of WGCNA, followed by construction of diagnostic models and regulation network establishment of long non-coding RNAs (lncRNAs)-miRNAs-diagnostic IRGs. Analysis of functional enrichment and protein-protein interaction (PPI) network and identification of related drugs of DEGs was performed. LILRB3 and CSF3R were identified as potential diagnostic markers for PD. Two regulatory pairs were identified based on LILRB3 and CSF3R, including XIST-hsa-miR-214-3p/hsa-miR-761-LILRB3 and XIST-hsa-miR-485-5p/hsa-miR-654-5p-CSF3R. LEP and IL1A were drug targets of Olanzapine. MMP9 and HSP90AB1 were drug targets of Bevacizumab. In addition, LEP and MMP9 were respectively drug targets of Lovastatin and Celecoxib. Herpes simplex infection (involved TNFRSF1A) and cytokine-cytokine receptor interaction (involved CSF3R, LEP, and IL1A) were the most remarkably enriched signaling pathways of DEGs. Identified IRGs and related signaling pathways may play critical roles in the development of PD. Additionally, LILRB3 and CSF3R can be considered as potential immune-related diagnostic markers for PD. LEP, IL1A, MMP9, and HSP90AB1 may be regarded as immune-related therapeutic targets for PD.

Para-Hydroxybenzyl Alcohol Delays the Progression of Neurodegenerative Diseases in Models of Caenorhabditis elegans through Activating Multiple Cellular Protective Pathways

The traditional Chinese medicine Gastrodia elata (commonly called “Tianma” in Chinese) has been widely used in the treatment of rheumatism, epilepsy, paralysis, headache, and dizziness. Phenolic compounds, such as gastrodin, para-hydroxybenzyl alcohol (HBA), p-hydroxybenzaldehyde, and vanillin are the main bioactive components isolated from Gastrodia elata. These compounds not only are structurally related but also share similar pharmacological activities, such as antioxidative and anti-inflammatory activities, and effects on the treatment of aging-related diseases. Here, we investigated the effect of para-hydroxybenzyl alcohol (HBA) on neurodegenerative diseases and aging in models of Caenorhabditis elegans (C. elegans). Our results showed that HBA effectively delayed the progression of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and Huntington's disease in models of C. elegans. In addition, HBA could increase the average lifespan of N2 worms by more than 25% and significantly improve the age-related physiological functions of worms. Moreover, HBA improved the survival rate of worms under stresses of oxidation, heat, and pathogenic bacteria. Further mechanistic investigation revealed that HBA could activate FOXO/DAF-16 and SKN-1 to regulate antioxidative and xenobiotic metabolism pathway. HBA could also activate HSF-1 to regulate proteostasis maintenance pathway, mitochondrial unfolded stress response, endoplasmic stress response and autophagy pathways. The above results suggest that HBA activated multiple cellular protective pathways to increase stress resistance and protect against aging and aging-related diseases. Overall, our study indicates that HBA is a potential candidate for future development of antiaging pharmaceutical application.

Fish oil ameliorates neuropsychiatric behaviors and gut dysbiosis by elevating selected microbiota-derived metabolites and tissue tight junctions in rats under chronic sleep deprivation

Neuropsychiatric behaviors caused by sleep deprivation (SD) are severe public health problems in modern society worldwide. This study investigated the effect of fish oil on neuropsychiatric behaviors, barrier injury, microbiota dysbiosis, and microbiota-derived metabolites in SD rats. The rats subjected to SD had significantly elevated blood levels of corticosteroid and lipopolysaccharides and exhibited anxiety-like behavior in the open field test, depression-like behavior in the forced swim test, and cognitive impairment in the Morris water maize test. We observed that the upregulation of proinflammatory cytokines in the SD rats resulted in colonic epithelial barrier injury including a decreased number of goblet cells and increased expression of selected tight junction proteins in the gut and brain. The gut microbiome status revealed a significant decrease in the microbial diversity in the SD rats, especially in probiotics. By contrast, a fish oil-based diet reversed SD-induced behavioral changes and improved the epithelial barrier injury and dysbiosis of the microbiota in the colon. These findings could be attributable to the increase in probiotics and short-chain fatty acid (SCFAs) production, improvement in selected intestinal barrier proteins, increase in SCFA receptor expression, and decrease in blood circulation proinflammatory status due to fish oil supplementation.

Transcriptome sequencing reveals Gastrodia elata Blume could increase the cell viability of eNPCs under hypoxic condition by improving DNA damage repair ability

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume (GEB), known as Tianma in China, is a traditional medicinal herb that has been reported to have various pharmacological effects and neuroprotection, has long been used for treating dizziness, epilepsy, stroke. However, explanation of its underlying mechanisms remains a great challenge.

AIM OF THE STUDY

The neuroprotective mechanism of GEB on hypoxia-induced neuronal injury in cultured mouse embryonic neural progenitor cells (eNPCs) was investigated, with emphasis on the eNPCs proliferation and DNA damage repair.

MATERIALS AND METHODS

In this study, hypoxia was focused, which may be caused by stroke or acute cerebral ischemia and is considered as one of the important factors contributing to the Central Nervous System diseases. CoCl₂ was adopted to construct a hypoxic/ischemic condition in eNPCs. eNPCs proliferation analysis validated GEB neuroprotective effect under hypoxic/ischemic condition. Transcriptome and weighted gene co-expression network analysis (WGCNA) screened the special gene-network module correlated with what appeared to have significant positive correlation with GEB. Then, Gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed to explore the biological functions of selected genes in the modules that had high correlation with GEB.

RESULTS

GEB has neuroprotective effect and could rescue eNPCs proliferation under hypoxic/ischemic condition induced by CoCl₂. Transcriptome and WGCNA unveil the neuroprotective mechanism of GEB on improving DNA damage repair ability by increasing the expression of genes associated with DNA repair and replication. Western blotting and qPCR showed that GEB could improve DNA damage repair ability by increasing the expression of Mcm2, Mcm6, Pold2, Pole, Pole2, Rfc1, Pole4, Dna2 and Rpa2, which were associated with DNA damage and replication.

CONCLUSION

Through transcriptome and WGCNA, this study unveiled Gastrodia elata Blume could increase the cell viability of eNPCs under hypoxic condition by improving DNA damage repair ability.

Antidepressant-like effects of water extract of Cordyceps militaris (Linn.) Link by modulation of ROCK2/PTEN/Akt signaling in an unpredictable chronic mild stress-induced animal model

ETHNOPHARMACOLOGY RELEVANCE

Cordyceps militaris (Linn.) Link (CM) is a medicinal mushroom traditionally used in tonics for treating several neurological disorders, including epilepsy and anxiety, in Asia. Reports have shown that CM has anti-inflammatory and anti-oxidative effects and may be beneficial for depression management.

AIM OF THE STUDY

This study aimed to investigate the potential of CM as an antidepressant for a long-term unpredictable chronic mild stress (UCMS) rodent models and explore its underlying mechanisms.

MATERIALS AND METHODS

Rats were orally administered with 125 (low, L), 250 (medium, M), and 500 (high, H) mg/kg bodyweight (bw) of the water extract of CM (WCM) for 35 consecutive days in the UCMS protocol. The levels of cerebral serotonin (5-HT), dopamine (DA), and metabolites in the frontal cortex of the rats were measured. Blood was collected to investigate the levels of proinflammatory cytokines, and the brain was dissected to assay the stress-associated ROCK2/PTEN/Akt signaling.

RESULTS

All doses of the WCM prevented abnormal behaviors induced by UCMS, including anhedonia and hypoactivity. The LWCM treatment reduced the turnover rate of 5-HT, and all doses of the WCM reduced the turnover rate of DA in the frontal cortex. The LWCM also attenuated the elevation of serum IL-1β induced by chronic stress. All doses of the WCM attenuated the ROCK2 protein hyperactivation, and the LWCM further increased the down-regulation of p-Akt/Akt signaling.

CONCLUSION

The WCM has antidepressant-like effects, which may result from the regulation of the stress-related ROCK2/PTEN/Akt pathway. Therefore, the WCM may be developed and used for the complementary treatment of depression.

Medicinal Plants in the Treatment of Depression: Evidence from Preclinical Studies

Medicinal plants and their extracts are natural remedies with enormous potential for treating various diseases, including depression and anxiety. In the case of depression, hundreds of plants have traditionally been used in folk medicine for generations. Different plant extracts and natural products have been analyzed as potential antidepressant agents with validated models to test for antidepressant-like effects in animals, although other complementary studies have also been employed. Most of these studies focus on the possible mediators implicated in these potential effects, with dopamine, serotonin, and noradrenaline being the principal neurotransmitters implicated, both through interference with receptors and with their metabolism by monoamino oxidases, as well as through neuro-endocrine and neuroprotective effects. There are approximately 650 reports of antidepressant-like medicinal plants in PubMed; 155 of them have been compiled in this review, with a relevant group yielding positive results. Saffron and turmeric are the most relevant species studied in both preclinical and clinical studies; St. John's wort or kava have also been tested extensively. To the best of our knowledge, no review to date has provided a comprehensive understanding of the biomolecular mechanisms of action of these herbs or of whether their potential effects could have real benefits. The purpose of this narrative review is to provide an update regarding medicinal plants from the year 2000 to the present to examine the therapeutic potential of these antidepressant-like plants in order to contribute to the development of new therapeutic methods to alleviate the tremendous burden that depression causes worldwide.

Gastrodia elata Blume water extract modulates neurotransmitters and alters the gut microbiota in a mild social defeat stress-induced depression mouse model

Gastrodia elata Blume has multiple bioactive functions, such as antioxidant and antidepressant activities, immune modulation, neuroplasticity, and neuroprotection. We previously found that the water extract of G. elata exerts antidepressant-like effects in unpredictable chronic mild stress models and animals exposed to the forced swimming test. We aimed to investigate the mechanisms by which the water extract of G. elata protects against subchronic- and mild-social defeat-stress-induced dysbiosis. After a 10-day subchronic and mild-social-defeat-stress program, oral treatment with the water extract of G. elata (500 mg/kg bw) resulted in reversal of depression-like behavior. In addition, monoamine analyses showed that the water extract of G. elata normalized the 5-hydroxyindoleacetic acid:5-HT ratio in the prefrontal cortex and colon and reduced the defeat-stress-induced kynurenine:tryptophan ratio in the colon. After the 10-day subchronic and mild social-defeat-stress program, the water extract of G. elata altered the intestinal microbiome by increasing Actinobacteria levels, modulating intestinal inflammation, and shifting the relative abundances of multiple bacterial groups in the gut. Our results suggest that the water extract of G. elata exhibits a potent antidepressant-like effect via the regulation of monoaminergic neurotransmission and alteration of gut microbiota composition and function, and that it may be an effective prevention for depression.

Protective Effect of Hydroxysafflor Yellow A against Chronic Mild Stress-induced Memory Impairments by Suppressing Tau Phosphorylation in Mice

Chronic stress plays a critical role in the etiology of sporadic Alzheimer's disease (AD). However, there are currently no effective drugs that can target chronic stress to prevent AD. In this study, we explored the neuroprotective effect of hydroxysafflor yellow A (HSYA) against chronic mild stress (CMS)-induced memory impairments in mice and the underlying mechanism. The Morris water maze test showed that HSYA significantly reduced CMS-induced learning and memory impairments in mice. HSYA increased the expression of brain-derived neurotrophic factor (BDNF) and activated downstream tropomyosin-related kinase B (TrkB) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B(Akt)/mammalian target of rapamycin (mTOR) signaling. HSYA decreased the expression of regulator of calcineurin 1-1L (RCAN1-1L) that could promote the activity of glycogen synthase kinase-3β (GSK-3β). HSYA also attenuated tau phosphorylation by inhibiting the activity of GSK-3β and cyclin-dependent kinase-5 (Cdk5). Our data indicated that HSYA has protective effects against CMS-induced BDNF downregulation, tau phosphorylation and memory impairments. HSYA may be a promising therapeutic candidate for AD by targeting chronic stress.

Gastrodiae Rhizoma Water Extract Ameliorates Hypothalamic-Pituitary-Adrenal Axis Hyperactivity and Inflammation Induced by Chronic Unpredictable Mild Stress in Rats

Gastrodiae Rhizoma is a highly valuable traditional herbal medicine commonly used to treat neurological disorders. The present study is designed to determine the antidepressant-like effect of the Gastrodiae Rhizoma water extract (GRWE) on a depression model and the potential mechanisms. The chronic unpredictable mild stress (CUMS) rat model was used to induce depression. The sucrose preference test, open field test, forced swimming test, and tail suspension test were performed to assess the depressive-like behaviors, respectively. Hypothalamic-pituitary-adrenal (HPA) function was measured via plasma corticosterone (CORT), adrenocorticotrophic hormone (ACTH), hypothalamic corticotropin-releasing factor (CRF), and glucocorticoid receptor (GR) concentrations. Plasma concentrations of proinflammatory cytokines including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were also evaluated. The results showed that GRWE significantly attenuates the behavioral abnormalities in CUMS rats, as shown by elevated sucrose consumption, raised locomotor activity, and reduced immobility duration. Moreover, GRWE treatment reduced CORT, ACTH, CRF, and GR levels and decreased the plasma IL-1β, IL-6, and TNF-α concentrations. These findings indicate that GRWE improves depressive behaviors in a chronic stress model of rats; its effect may be ascribed to the modulation of the HPA axis activity and inflammatory response.

Water extract of Armillaria mellea (Vahl) P. Kumm. Alleviates the depression-like behaviors in acute- and chronic mild stress-induced rodent models via anti-inflammatory action

ETHNOPHARMACOLOGY RELEVANCE

Armillaria mellea (Vahl) P. Kumm. (AM) is an edible mushroom that has been reported as treatment for several neurological disorders, such as dizziness and epilepsy in Asia. Importantly, AM shares a symbiotic relationship with Gastrodia elata Blume (GE), a medicinal herb with antidepressant-like properties. Researchers believe that AM may possess pharmacological properties similar to GE due to their symbiosis, however, few studies have investigated the pharmacological effect of AM.

AIM OF THE STUDY

The aim of this study was to explore the potential of AM as an antidepressant in forced-swimming test (FST) and unpredictable chronic mild stress (UCMS) rodent models and investigate its possible underlying mechanism.

MATERIALS AND METHODS

Rats were orally administrated with 250, 500, and 1000 mg/kg body weight (bw) water extract of AM (WAM) for 28 and 35 consecutive days prior to the FST and UCMS protocols, respectively. The cerebral serotonin (5-HT) and the metabolites in the frontal cortex of rats were measured. The brain was dissected and the blood was collected to investigate the levels of inflammatory-related signaling pathway.

RESULTS

All doses of WAM reduced the immobility time in the FST without disturbing autonomic locomotion. All doses of WAM prevented stress-induced abnormal behaviors in the UCMS model, including decreased sucrose preference and hypoactivity. 500 and 1000 mg/kg bw WAM attenuated the stress-induced increases in IL-1β and TNF-α in the serum and cerebrum. 1000 mg/kg bw WAM alleviated brain inflammation by reducing the protein expression of ionized calcium binding adaptor molecule 1.

CONCLUSION

WAM exhibited acute and chronic antidepressant-like effects, and may result from the anti-inflammatory actions. Therefore, the development of AM as a dietary therapy or adjuvant for depression treatment should be considered.

Glial Nrf2 signaling mediates the neuroprotection exerted by Gastrodia elata Blume in Lrrk2-G2019S Parkinson's disease

The most frequent missense mutations in familial Parkinson's disease (PD) occur in the highly conserved LRRK2/PARK8 gene with G2019S mutation. We previously established a fly model of PD carrying the LRRK2-G2019S mutation that exhibited the parkinsonism-like phenotypes. An herbal medicine, Gastrodia elata Blume (GE), has been reported to have neuroprotective effects in toxin-induced PD models. However, the underpinning molecular mechanisms of GE beneficiary to G2019S-induced PD remain unclear. Here, we show that these G2019S flies treated with water extracts of GE (WGE) and its bioactive compounds, gastrodin and 4-HBA, displayed locomotion improvement and dopaminergic neuron protection. WGE suppressed the accumulation and hyperactivation of G2019S proteins in dopaminergic neurons and activated the antioxidation and detoxification factor Nrf2 mostly in the astrocyte-like and ensheathing glia. Glial activation of Nrf2 antagonizes G2019S-induced Mad/Smad signaling. Moreover, we treated LRRK2-G2019S transgenic mice with WGE and found that the locomotion declines, the loss of dopaminergic neurons, and the number of hyperactive microglia were restored. WGE also suppressed the hyperactivation of G2019S proteins and regulated the Smad2/3 pathways in the mice brains. We conclude that WGE prevents locomotion defects and the neuronal loss induced by G2019S mutation via glial Nrf2/Mad signaling, unveiling a potential therapeutic avenue for PD.

Potential effect of herbal antidepressants on cognitive deficit: Pharmacological activity and possible molecular mechanism

ETHNOPHARMACOLOGICAL RELEVANCE

Cognitive symptom is a "core" symptom of major depressive disorder (MDD) patients with clear deficit in memory, social and occupational function, and may persist during the remitting phase. Therefore, the remission of cognitive symptom has been considered as one of the main objectives in the treatment of MDD. Herbal antidepressants have been used to treat MDD, and there has been great advances in the understanding of the ability of these herbs to improve cognitive deficit linked to brain injury and various diseases including depression, Alzheimer disease, diabetes and age-related disorders. This systematic review summarizes the evidence from preclinical studies and clinical trials of herbal antidepressants with positive effects on cognitive deficit. The potential mechanisms by which herbal antidepressants prevent cognitive deficit are also reviewed. This review will facilitate further research and applications.

MATERIALS AND METHODS

We conducted an open-ended, English restricted search of MEDLINE (PubMed), Web of Science and Scopus for all available articles published or online before 31 December 2019, using terms pertaining to medical herb/phytomedicine/phytochemical/Chinese medicine and depression/major depressive disorder/antidepressant and/or cognitive impairment/cognitive deficit/cognitive dysfunction.

RESULTS

7 prescriptions, more than 30 individual herbs and 50 phytochemicals from China, Japan, Korea and India with positive effects on the depressive state and cognitive deficit are reviewed herein. The evidence from preclinical studies and clinical trials proves that these herbal antidepressants exhibit positive effects on one or more aspects of cognitive defect including spatial, episodic, aversive, and short- and long-term memory. The action mode of the improvement of cognitive deficit by these herbal antidepressants is mediated mainly through two pathways. One pathway is to promote hippocampal neurogenesis through activating brain derived neurotrophic factor-tropomyosin-related kinase B signaling. The other pathway is to prevent neuronal apoptosis through the inhibition of neuro-inflammation and neuro-oxidation.

CONCLUSION

These herbal antidepressants, having potential therapy for cognitive deficit, may prevent pathological processes of neurodegenerative diseases. Furthermore, these herbal medicines should provide a treasure trove, which will accelerate the development of new antidepressants that can effectively improve cognitive symptom in MDD. Studies on their molecular mechanisms may provide more potential targets and therapeutic approaches for new drug discovery.

Garlic essential oil mediates acute and chronic mild stress-induced depression in rats via modulation of monoaminergic neurotransmission and brain-derived neurotrophic factor levels

Garlic essential oil (GEO) and its major organosulfur component (diallyl disulfide, DADS) possess diverse biological properties; however, limited information on their antidepressant-like effects is available. This study is the first to investigate these effects of GEO using the forced swimming test (FST) and unpredictable chronic mild stress (UCMS) induced depression in rats. After oral administration for 28 consecutive days, GEO (25 and 50 mg per kg bw) significantly reduced the immobility time in the FST. Additionally, GEO and DADS significantly reversed the sucrose preference index decrease induced by 5 weeks of UCMS. GEO (25 mg per kg bw) effectively decreased the frontal cortex turnover ratio of serotonin (5-HT) and dopamine (DA), thus increasing the 5-HT and DA levels, with no hippocampal effects. Chronic GEO treatment increased hippocampal brain-derived neurotrophic factor (BDNF), c-AMP response element binding protein (CREB), and protein kinase B (AKT) expression, exhibiting its effects via monoamine neurotransmitter modulation and the BDNF-related signaling pathway.

Degree of lipid saturation affects depressive-like behaviour and gut microbiota in mice

This study explored the effects of the degree of lipid saturation on depressive behaviour and gut microbiota in mice. Thirty-two mice were divided into normal (N), Prozac (NP), lard (L) and fish oil (F) groups. After a 12-week dietary intervention, the open field test (OFT) and the forced swim test (FST) were conducted before sacrifice. The mice in the L group exhibited anxiety-like behaviours in the OFT and depressive-like behaviours in the FST. A significant difference was observed in β-diversity indices between the L group and the F group. The abundance of Allobaculum and Bifidobacterium was significantly higher in the F group than in the L and N groups. The prefrontal cortex fatty acid composition was altered in various lipid-treated groups and was highly correlated with depressive-like behaviours. In conclusion, the degree of lipid saturation affects depressive-like behaviour, gut microbiota composition, and the prefrontal cortex fatty acid profile in mice.

Transformation Mechanisms of Chemical Ingredients in Steaming Process of Gastrodia elata Blume

To explore the transformation mechanisms of free gastrodin and combined gastrodin before and after steaming of Gastrodia elata (G. elata), a fresh G. elata sample was processed by the traditional steaming method prescribed by Chinese Pharmacopoeia (2015 version), and HPLC-ESI-TOF/MS method was used to identify the chemical composition in steamed and fresh G. elata. Finally, 25 components were identified in G. elata based on the characteristic fragments of the compounds and the changes of the 25 components of fresh and steamed G. elata were compared by the relative content. Hydrolysis experiments and enzymatic hydrolysis experiments of 10 monomer compounds simulating the G. elata steaming process were carried out for the first time. As a result, hydrolysis experiments proved that free gastrodin or p-hydroxybenzyl alcohol could be obtained by breaking ester bond or ether bond during the steaming process of G. elata. Enzymatic experiments showed that steaming played an important role in the protection of gastrodin, confirming the hypothesis that steaming can promote the conversion of chemical constituents of G. elata—inhibiting enzymatic degradation. This experiment clarified the scientific mechanism of the traditional steaming method of G. elata and provided reference for how to apply G. elata decoction to some extent.

Narirutin produces antidepressant-like effects in a chronic unpredictable mild stress mouse model

Depression is a highly debilitating and life-threatening mental disorder, which is accompanied by dysregulation of the peripheral and central immune system. Narirutin (NR), which has antioxidant and anti-inflammatory activities, is one of the active constituents isolated from Citrus unshiu. However, its potential antidepressant-like and anxiolytic-like effects are poorly understood. The present study was aimed to investigate whether NR confers an antidepressant-like effect in mice exposed to a chronic mild stress (CMS) model of depression. The results showed that NR treatment for 1 week significantly alleviated the depressive-like behaviours of CMS-exposed mice, as indicated by restored decreased sucrose preference and shortened floating time in the forced swimming test. Moreover, NR treatment significantly blocked the CMS-induced anxiety-like behaviors, including increased time spent in the central zone in the open field test, and shortened the latency to feeding in the novelty suppressed feeding test. Taken together, our findings suggested that NR exerted potential antidepressant-like and anxiolytic-like effects in CMS mice model of depression, which support further exploration into developing NR as a novel agent to treat depression and even other stress-related disorders.

The Antidepressant-like Effect of Flavonoids from Trigonella Foenum-Graecum Seeds in Chronic Restraint Stress Mice via Modulation of Monoamine Regulatory Pathways

Fenugreek (Trigonella Foenum-Graecum) seeds flavonoids (FSF) have diverse biological activities, while the antidepressant-like effect of FSF has been seldom explored. The aim of this study was to evaluate the antidepressant-like effect of FSF and to identify the potential molecular mechanisms. LC-MS/MS was used for the determination of FSF. Chronic restraint stress (CRS) was used to establish the animal model of depression. Observation of exploratory behavior in the forced swimming test (FST), tail suspension test (TST) and sucrose preference test (SPT) indicated the stress level. The serum corticosterone (CORT) level was measured. The monoamine neurotransmitters (5-HT, NE and DA) and their metabolites, as well as monoamine oxidase A (MAO-A) enzyme activity in the prefrontal cortex, hippocampus and striatum, were evaluated. The protein expression levels of KLF11, SIRT1, MAO-A were also determined by western blot analysis. The results showed that FSF treatment significantly reversed the CRS-induced behavioral abnormalities, including reduced sucrose preference and increased immobility time. FSF administration markedly restored CRS induced changes in concentrations of serum corticosterone, prefrontal cortex neurotransmitters (NE, 5-HT and DA), hippocampus neurotransmitters (NE, 5-HT and DA) and striatum neurotransmitters (NE). FSF treatment exhibited significant inhibition of MAO-A activity in the prefrontal cortex and hippocampus. FSF also significantly down-regulated the KLF11, SIRT1 and MAO-A protein expression levels in the prefrontal cortex and hippocampus. These findings indicate that FSF could exhibit an antidepressant-like effect by down-regulating the KLF11/SIRT1-MAO-A pathways, inhibiting MAO-A expression and activity, as well as up-regulating monoamine neurotransmitters levels.

Low temperature-aged garlic extract suppresses psychological stress by modulation of stress hormones and oxidative stress response in brain

BACKGROUND

Garlic is a folk medicine known for its multiple physiological activities, but the neuro-modulatory effect of garlic against psychological stress has rarely been explored. The current study was conducted to determine the potential antipsychological stress effect of low temperature-aged garlic (LTAG).

METHODS

After acute restraint stress exposure, mice were administered with raw garlic (RG, 500 mg/kg, p.o.) or LTAG (500 mg/kg, p.o.). We investigated corticosterone, cortisol, and monoamines levels, and the mRNA expression of genes relevant to oxidative stress.

RESULTS

RG and LTAG treatment significantly decreased stress-related hormones such as corticotropin-releasing factor, adrenocorticotropic hormone, corticosterone, and cortisol. Moreover, RG and LTAG administration significantly restored acute restraint stress-induced changes in concentrations of brain neurotransmitters (serotonin, norepinephrine, dopamine, and epinephrine). In addition, RG and LTAG improved the antioxidant defense system by causing an increase in mRNA expression of superoxide dismutase, catalase, and glutathione peroxidase in the brain.

CONCLUSION

This study suggests an antipsychological stress and neuroprotective effect of RG and LTAG under stress conditions.

Optimal Extraction Study of Gastrodin-Type Components from Gastrodia Elata Tubers by Response Surface Design with Integrated Phytochemical and Bioactivity Evaluation

Gastrodia elata tuber (GET) is a popular traditional Chinese medicines (TCMs). In this study, response surface methodology (RSM) with a Box–Behnken design (BBD) was performed to optimize the extraction parameters of gastrodin-type components (gastrodin, gastrodigenin, parishin A, parishin B, parishin C and parishin E). Different from the conventional studies that merely focused on the contents of phytochemical, we gave consideration to both quantitative analysis of the above six components by HPLC and representative bioactivities of GET, including antioxidation and protection of human umbilical vein endothelial cells (HUVEC). Four independent variables (ethanol concentration, liquid-material ratio, soaking time and extraction time) were investigated with the integrated evaluation index of phytochemical contents. With the validation experiments, the optimal extraction parameters were as follows: ethanol concentration of 41%, liquid–solid ratio of 28.58 mL/g, soaking time of 23.91 h and extraction time of 46.60 min. Under the optimum conditions, the actual standardized comprehensive score was 1.8134 ± 0.0110, which was in accordance with the predicted score of 1.8100. This firstly established method was proved to be feasible and reliable to optimize the extraction parameters of the bioactive components from GET. Furthermore, it provides some reference for the quality control and extraction optimization of TCMs.

Antidepressant-like effects of water extract of Gastrodia elata Blume on neurotrophic regulation in a chronic social defeat stress model

ETHNOPHARMACOLOGY RELEVANCE

Gastrodia elata Blume (GE) is a traditional Chinese medicine commonly used to treat dizziness, epilepsy, paralysis and some emotional symptoms in east Asia. We previously showed that the water extract of Gastrodia elata Blume (WGE) possesses anti-depression like effects in a forced swimming test and chronic mild stress model.

AIM OF THE STUDY

The aim of this study was to investigate the antidepressant-like effects of WGE and potential mechanisms related to brain-derived neurotrophic factor (BDNF) regulation in mice exposed to chronic social defeat stress (CSDS) model.

MATERIALS AND METHODS

Fifty C57BL/6 mice were divided into 5 groups as follows: a control (CTL) group, CSDS group, and 3 WGE groups receiving 250, 500 or 1000mg/kg body weight in the CSDS model. Mice were administered WGE for 24 days by oral gavage, and the social defeat stress paradigm began on day 14, except for the control group. A social interaction test was conducted to evaluate the antidepressant-like effects of WGE. Blood samples were collected to measure serum corticosterone levels, and the brain was dissected to investigate the expression of BDNF-related signaling pathway proteins using western blotting.

RESULTS

Oral administration of WGE improved depression-like behaviors and stress-induced elevations of corticosterone. Further, WGE increased the protein expression of BDNF and promoted the hippocampal protein phosphorylation ratio of cAMP response element binding protein (CREB) and protein kinase B (Akt).

CONCLUSION

WGE exerts antidepressant-like effects on mice in a CSDS model, likely through activating of the BDNF/CREB/Akt pathway. Therefore, WGE has potential as a supplement or an adjuvant to prevent or treat clinical depressive disorders.

A Review on Central Nervous System Effects of Gastrodin

Rhizoma Gastrodiae (also known as Tian ma), the dried rhizome of Gastrodia elata Blume, is a famous Chinese herb that has been traditionally used for the treatment of headache, dizziness, spasm, epilepsy, stoke, amnesia and other disorders for centuries. Gastrodin, a phenolic glycoside, is the main bioactive constituent of Rhizoma Gastrodiae. Since identified in 1978, gastrodin has been extensively investigated on its pharmacological properties. In this article, we reviewed the central nervous system (CNS) effects of gastrodin in preclinical models of CNS disorders including epilepsy, Alzheimer's disease, Parkinson's disease, affective disorders, cerebral ischemia/reperfusion, cognitive impairment as well as the underlying mechanisms involved and, where possible, clinical data that support the pharmacological activities. The sources and pharmacokinetics of gastrodin were also reviewed here. As a result, gastrodin possesses a broad range of beneficial effects on the above-mentioned CNS diseases, and the mechanisms of actions include modulating neurotransmitters, antioxidative, anti-inflammatory, suppressing microglial activation, regulating mitochondrial cascades, up-regulating neurotrophins, etc. However, more detailed clinical trials are still in need for positioning it in the treatment of neurological disorders.

How does early maternal separation and chronic stress in adult rats affect the immunoreactivity of serotonergic neurons within the dorsal raphe nucleus?

Vulnerability to emotional disorders like depression derives from interactions between early and late environments, including stressful conditions. The serotonin (5HT) system is strongly affected by stress and chronic unpredictable stress can alter the 5HT system. We evaluated the distribution of active serotonergic neurons in the dorsal raphe nucleus (DR) through immunohistochemistry in maternally separated and chronically stressed rats treated with an antidepressant, tianeptine, whose mechanism of action is still under review. Male Wistar rats were subjected to daily maternal separation (MS) for 4.5 h between postnatal days (PND) 1-21, or to animal facility rearing (AFR). Between (PND) days 50-74, rats were exposed to chronic unpredictable stress and were treated daily with tianeptine (10 mg/kg) or vehicle. We found an interaction between the effects of MS and chronic unpredictable stress on Fos-5HT immunoreactive cells at mid-caudal level of the DR. MS-chronically stressed rats showed an increase of Fos-5HT immunoreactive cells compared with AFR-chronically stressed rats. The ventrolateral (DRL/VLPAG) and dorsal (DRD) subdivisions of the DR were significantly more active than the ventral part (DRV). At the rostral level of the DR, tianeptine decreased the number of Fos-5HT cells in DR in the AFR groups, both unstressed and stressed. Overall, our results support the idea of a match in phenotype exhibited when the early and the adult environment correspond.

miR-16 and Fluoxetine Both Reverse Autophagic and Apoptotic Change in Chronic Unpredictable Mild Stress Model Rats

In the clinic selective serotonin reuptake inhibitors (SSRIs), like Fluoxetine, remain the primary treatment for major depression. It has been suggested that miR-16 regulates serotonin transporters (SERT) via raphe nuclei and hippocampal responses to antidepressants. However, the underlying mechanism and regulatory pathways are still obtuse. Here, a chronic unpredicted mild stress (CUMS) depression model in rats was established, and then raphe nuclei miR-16 and intragastric Fluoxetine injections were administered for a duration of 3 weeks. An open field test and sucrose preference quantification displayed a significant decrease in the CUMS groups when compare to the control groups, however these changes were attenuated by both miR-16 and Fluoxetine treatments. A dual-luciferase reporter assay system verified that hsa-miR-16 inhibitory effects involve the targeting of 3′UTR on the 5-HTT gene. Expression levels of miR-16 and BDNF in the hippocampus were examined with RT-PCR, and it was found that increased 5-HT2a receptor expression induced by CUMS can be decreased by miR-16 and Fluoxetine administration. Immunofluorescence showed that expression levels of neuron NeuN and MAP-2 in CUMS rats were lower. Apoptosis and autophagy levels were evaluated separately through relative expression of Bcl-2, Caspase-3, Beclin-1, and LC3II. Furthermore, CUMS was found to decrease levels of hippocampal mTOR, PI3K, and AKT. These findings indicate that apoptosis and autophagy related pathways could be involved in the effectiveness of antidepressants, in which miR-16 participates in the regulation of, and is likely to help integrate rapid therapeutic strategies to alleviate depression clinically. These findings indicate that miR-16 participates in the regulation of apoptosis and autophagy and could account for some part of the therapeutic effect of SSRIs. This discovery has the potential to further the understanding of SSRIs and accelerate the development of new treatments for depression.

Relative tissue distribution and excretion studies of gastrodin and parishin from powder and extract of Gastrodiae Rhizoma in rat by UHPLC-ESI-MS/MS

New research has indicated that Gastrodiae Rhizome (GR) has potential anti-diabetic and anti-asthmatic effects in mouse models. On the basis of our previous study of the relative bioavailability of gastrodin (GAS) and parishin (PA) from extract and powder of GR, we performed further research on the tissue distribution and excretion of the two analytes. A reliable bioanalytical method for the quantification of GAS and PA in rat tissues and excretion is required. Chromatographic separation was carried out on a gradient mobile phase of acetonitrile-water with 0.1% formic acid. Calibration curves (1/x² weighted) offered satisfactory linearity (r²  > 0.9835) within 100-3000 ng mL^-1 for GAS and (r²  > 0.9862) within 10-1000 ng mL^-1 for PA. The relative standard deviations of the intra-day and inter-day precision were all <14.98%, whilst the relative errors of the intra-day and inter-day accuracy were all within ±14.71%. The matrix effect and recovery values were satisfactory in all of the biological matrices examination. The data of relative differences in tissue distribution and excretion of GAS and PA from powder and extract of GR indicated that higher bioavailabilities for GAS and PA were obtained when a dosage of 4 g kg^-1 GR powder was used.

Structural Features and Potent Antidepressant Effects of Total Sterols and β-sitosterol Extracted from Sargassum horneri

The purified total sterols and β-sitosterol extracted from Sargassum horneri were evaluated for their antidepressant-like activity using the forced swim test (FST) and tail suspension test (TST) in mice. Total sterols and β-sitosterol significantly reduced the immobility time in the FST and TST. Total sterols were administered orally for 7 days at doses of 50, 100, and 200 mg/kg, and β-sitosterol was administered intraperitoneally at doses of 10, 20, and 30 mg/kg. β-sitosterol had no effect on locomotor activity in the open field test. In addition, total sterols and β-sitosterol significantly increased NE, 5-HT, and the metabolite 5-HIAA in the mouse brain, suggesting that the antidepressant-like activity may be mediated through these neurotransmitters.