Suspension Test Research Articles

Investigating the effect of chronic stress, depressive-like pathology and cognitive impairments on acute myocardial infarction: sex-differentiated effects

Abstract Background/Introduction Depression is an independent risk factor for cardiovascular disease (CVD) with the prevalence rates being higher in women than men in the general population and among patients with CVD. Furthermore, an association between myocardial infarction and cognitive deficits has been proposed, but the pathophysiological mechanisms that are responsible for the brain-heart axis interaction have not been elucidated. Purpose The present study aims to: 1) evaluate sex differences in the effect of chronic unpredictable stress (CUS) on myocardial infarct size (IS) and 2) determine the molecular pathways affected by CUS in the heart. Methods Adult male and female C57BL/6J mice, were randomly divided into 4 groups (n=7/group): CON (Control, sham surgery), iCON (Control, myocardial ischemia/reperfusion (IR)), STR (Stress, sham surgery) and iSTR (Stress, IR). Mice were intermittently exposed to the CUS protocol consisted of 4 different stressors for 6 consecutive weeks. Locomotor activity (open field-OF), anxiety-like alterations (OF, elevated plus-maze-EPM test), depressive-like pathology (tail suspension test- TST) and cognition (Y-maze and Novel Object Recognition-NOR tests) were evaluated. After behavioral evaluation, the animals were subjected to 30 min I followed by 24 h of R or sham surgery and infarct size (IS) was determined via double Evan’s Blue and triphenyltetrazolium chloride staining. In a second series of experiments (n=5/group), the ischemic part of the myocardium was collected at 24h R and subjected to label free proteomic analysis, in order to identify alterations associated with the effect of CUS and IR. Results CUS induced anxiety, depressive-like pathology and cognitive deficits as indicated by the increased time spent in the closed arms of the EPM (p<0.005), the increased immobility time (TST, p<0.05), the reduced preference for the novel object (NOR, p<0.05), and the significant body weight reduction (p<0.001), in both male and female mice. CUS significantly increased IS (p<0.001) in both male and female mice. Proteomic analysis revealed that CUS affected the heart proteome, related to endoplasmic reticulum stress, mitochondrial damage and apoptosis, of both sexes in the absence of IR. Female mice were more susceptible to IR damage in absence of CUS with 248 significant genes (FDR<0.05) being deregulated mainly belonging to Keap-Nrf2-ARE signaling pathway, in contrast to 168 significant genes in male mice. In male mice, CUS exacerbated the IR injury proteome changes mainly related to induction of apoptosis and mitochondrial dysregulation (292 significant genes, FDR<0.05 for males vs 102 for females). Conclusions Chronic exposure to stress increases depressive-like pathology and cognitive deficits, leading to heart proteome alterations and increased IS in both sexes. Sex differences were observed indicating that the coexistence of CUS and IR render the male heart more susceptible to myocardial damage.

6-Methoxyflavone improves anxiety, depression, and memory by increasing monoamines in mice brain: HPLC analysis and in silico studies

Abstract 6-Methoxyflavone (6-MOF) is a flavonoid that has been reported to be a GABA-A receptor agonist and reverses cisplatin-induced hyperalgesia and allodynia. Considering the varied neuropharmacological profile of 6-MOF, this study was intended to determine the pharmacological effects of 6-MOF on locomotion, anxiety, novel object recognition (NOR), depression, spatial memory, socialization behavior, nest-building behavior, and depression in various groups of mice. Selected groups of mice were injected with 25, 50, and 75 mg/kg 6-MOF. Using HPLC-UV, the frontal cortex, striatum, and hippocampus of the sacrificed mice were analyzed for the levels of vitamin C, dopamine, serotonin, noradrenaline, adenosine, and its metabolites. Statistical analysis showed significant results in socialization behavior and elevated plus maze with 75 mg/kg. In Y-maze, NOR 6-MOF showed significant results at all three doses, while in tail suspension test (TST), 50 and 75 mg/kg showed significant results; however, no statistical significance was observed in nest-building behavior; 50 and 75 mg/kg 6-MOF showed significant results in the Morris water maze. 6-MOF raised vitamin C levels in the frontal cortex and hippocampus. Serotonin, dopamine, and nor-adrenaline levels were raised in the hippocampus and striatum. It has also imparted region-specific neuroprotection by improving adenosine and its metabolite levels. In silico studies performed using PyRx have shown that the minimum binding energy of 6-MOF with antioxidant enzyme is −7.1 k/cal/mol. The binding energy showed that 6-MOF was successfully docked with an anti-oxidant enzyme. In conclusion, in silico and behavioral studies showed that 6-MOF can be a potential candidate for the treatment of cognitive decline, anxiety, and depression.

Paroxetine Loaded Nanostructured Lipid Carriers Based In-situ Gel for Brain Delivery via Nasal Route for Enhanced Anti-Depressant Effect: In Vitro Prospect and In Vivo Efficacy.

This study focused on developing a thermosensitive gel with nanostructured lipid carriers (NLCs) loaded with paroxetine (PAR) to enhance the treatment and management of depression via nasal administration. Micro emulsion technique was utilized for the PAR-NLCs preparation. The acetyl alcohol and oleic acid were used in the ratio of 76:24. In the NLCs Tween 40, Span40 and Myrj 52 were used as a surfactant. The NLCs were then added into Poloxamer mixture to get thermosensitive NLCs based gel. Characterization, in vitro and in vivo studies were performed to check the efficiency of formulation in drug delivery. The entrapment efficiency of optimized PAR-NLCs was about 90%. The particle size, zeta potential and PDI were 155 ± 1.4nm, -25.9 ± 0.5mV, and 0.12 ± 0.01 respectively. The optimized gel showed a gelling temperature of 31.50 ± 0.50°C and a gelling time of 1 ± 0.12s with a pH of 6, suitable for nasal administration. The in vitro release assay of PAR-NLC-gel showed a cumulative release of about 59% in the first 6h after comparison with PAR-NLCs which showed almost 100%release. In vivo studies included forced swim test and tail suspension tests showed significant potential for treating depression when compared to PAR-NLCs. PAR-NLCs and NLCs based gel enhanced the tissue architecture and suppressed the expression of TNF-α in brain cortex from histological and immunohistochemical analysis. PAR- NLCs gel-based delivery system can prove to be an effective delivery system for brain targeting through nose for the better management of depression.

Antidepressant-like Effects of Cannabis sativa L. Extract in an Lipopolysaccharide Model: Modulation of Mast Cell Activation in Deep Cervical Lymph Nodes and Dura Mater.

Lipopolysaccharide (LPS)-induced neuroinflammation is a well-established model for studying depression-like behavior, driven by pro-inflammatory cytokines such as TNF-α and IL-1β. Mast cells (MCs) contribute to neuroinflammation by releasing mediators that exacerbate depressive-like symptoms. This study evaluates the antidepressant-like and anti-inflammatory effects of Cannabis sativa L. inflorescence extract (CSL) in an LPS-induced neuroinflammation model. Male C57BL/6 mice were intraperitoneally injected with CSL at doses of 10, 20, and 30 mg/kg, 30 min prior to LPS (0.83 mg/kg) administration. Depressive behaviors were assessed using the sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST). The neutrophil-to-lymphocyte ratio (NLR) was measured to assess systemic inflammation. Cytokine levels in the prefrontal cortex (PFC) were measured, and mast cell degranulation in the lymph nodes and dura mater was analyzed histologically (approval number: WKU24-64). CSL significantly improved depressive-like behaviors and decreased the NLR, indicating reduced systemic inflammation. CSL also significantly reduced TNF-α and IL-1β levels in the PFC. Furthermore, CSL inhibited MC degranulation in the deep cervical lymph nodes and dura mater, with the strongest effects observed at 30 mg/kg. CSL demonstrated antidepressant-like and anti-inflammatory effects in an LPS-induced neuroinflammation model, likely through the modulation of cytokine expression and mast cell activity. These results suggest the potential of CSL as a therapeutic option for treating inflammation-related depression.

Exploring the Neuroprotective Behaviour and Hepatoprotective Effects of Plumbagin in MPTP-Induced Parkinson's Disease

Aims: Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra, leading to motor symptoms like tremors and bradykinesia, as well as non-motor symptoms such as sleep disturbances and autonomic dysfunction. Recent research suggests a link between PD and liver dysfunction, including altered metabolism and elevated liver enzymes. Plumbagin, recognized for its antioxidant and neuroprotective properties, may offer therapeutic benefits. This study explores its effects on both motor and non-motor symptoms in MPTP-treated mice, as well as its impact on liver function through serum enzyme analysis. The aim is to assess the neuroprotective and hepatoprotective potential of plumbagin in countering MPTP-induced neurodegeneration and liver dysfunction. Methodology: Thirty mice (22-30g, 8-12 weeks old) were randomly assigned to five groups of six each. The experiment spanned 28 days, with the mice housed under controlled conditions and provided standard feed and water. Behavioral tests, including the Marble Burying and Tail Suspension tests, were conducted to assess anxiety and depressive-like behavior. Serum biochemistry, including ALT, AST, and BUN, was measured using standard ERBA kits to evaluate liver function health. Results: In the marble burying and tail suspension tests, MPTP-induced mice (DC group) exhibited significantly higher anxiety and depressive-like behaviors compared to the sham and plumbagin groups. Plumbagin treatment (PD) and levodopa (LS) significantly reduced these behavioral symptoms. Liver function markers (ALT, AST, ALP) and BUN levels were elevated in DC mice, indicating liver and kidney damage, while plumbagin treatment mitigated these effects, showing values comparable to the standard treatment (LS). Conclusion: This study demonstrates that MPTP exposure affects both the central nervous system and liver function, leading to anxiety, depression, and liver damage, as evidenced by elevated liver enzymes. Plumbagin showed protective effects, reducing these behavioral and biochemical changes through its antioxidant properties, suggesting its potential as a therapeutic agent against MPTP-induced neurotoxicity and hepatotoxicity. These findings suggest that future research should investigate plumbagin's clinical potential for treating Parkinson's disease and liver dysfunction, offering promise for its use in developing neuroprotective therapies.

An Assessment of Antidepressant Activity of Etlingera elatior Alone and in Combination with Fluoxetine

Aim: Present study deals to access the antidepressant activity of Etlingera elatior leaves extract in rodent. Background: Etlingera elatior is a species of herbaceous perennial plant in the family Zingiberaceae; native to Indonesia, Thailand, Malaysia and New Guinea. Depression is one of the most common mental disorders affecting humans, pathological basis of which is not fully understood. The current antidepressant drugs have several adverse effects including their effects on cognition. Therefore, natural product are being evaluated for their antidepressant activities. Objective: In this study, Etlingera elatior leaf extracts are being evaluated for antidepressant activity in rodent models. A wide range of synthetic medicines that can be used to treat depression which may exerts various side effects such as dry mouth, gastrointestinal problems, nausea, respiratory problems, cardiac arrhythmias, drowsiness, anxiety etc. Hence, it becomes essential to discover new anti-depressant drug with more potency, efficacy and safety profile than those of marketed synthetic drugs. Methods: Using the forced swimming test, the tail suspension test, mouse 5-HTP-induced head twitches and estimation of brain lipid peroxidation modelsthe antidepressant efficacy of Etlingera elatior ethanolic extract was examined. Imipramine was used as reference standards. result: According to our study, Etlingera elatior significantly (p0.01) reduced immobility in tail suspension, forced swimming, and 5-HTP-induced head twitches in mice with depression that were comparable to imipramine. Results: According to our study, Etlingera elatior significantly (p 0.01) reduced immobility in tail suspension, forced swimming, and 5-HTP-induced head twitches in mice with depression that were comparable to imipramine. Conclusion: Based on the results obtained we can conclude that Etlingera elatior leaves extract possess significant antidepressant activity. The antidepressant effectiveness of Etlingera elatior leaves extract can be confirmed in the future by adding more models, and attempts can also be made to isolate and characterise the phytoconstituents responsible for the pharmacological action.

Design, synthesis and biological evaluation of arylpropylamine derivatives as potential multi-target antidepressants

In this study, a series of novel arylpropylamine derivatives were designed, synthesized and evaluated as potential multi-target antidepressants. Among them, compound (R)-13j displayed unique pharmacological features, exhibiting excellent inhibitory potency against serotonin and noradrenaline transporters (SERT/NET) and high affinity for 5-HT2A/2C receptor, and showing low affinity for histamine H1, adrenergic α1 receptors and hERG channels (to reduce QT interval prolongation). Molecular docking studies provided a rational binding model of (R)-13j in complex with SERT and 5-HT2A/2C receptor. In animal models, compound (R)-13j dose-dependently reduced the immobility time in the tail suspension test (TST) and the forced swimming test (FST) in mice, with higher efficacy when compared to duloxetine, and showed no stimulatory effect on the locomotor activity. Moreover, compound (R)-13j significantly shortened the immobility time in the ACTH-induced rat model of treatment-resistant depression (TRD). Furthermore, compound (R)-13j also exhibited a higher threshold for acute toxicity than duloxetine. In addition, compound (R)-13j possessed a favorable pharmacokinetic profile in mice. Taken together, compound (R)-13j may constitute a novel class of drugs for the treatment of depression.

Quantitative proteomics combined independent PRM analysis reveals the mitochondrial and synaptic mechanism underlying norisoboldine’s antidepressant effects

Major depressive disorder (MDD) is a common disease affecting 300 million people worldwide. The existing drugs are ineffective for approximately 30% of patients, so it is urgent to develop new antidepressant drugs with novel mechanisms. Here, we found that norisoboldine (NOR) showed an antidepressant efficacy in the chronic social defeat stress (CSDS) depression model in the tail suspension, forced swimming, and sucrose consumption tests. We then utilized the drug-treated CSDS mice paradigm to segregate and gain differential protein groups of CSDS versus CON (CSDSCON), imipramine (IMI)-treated versus CSDS (IMICSDS), and NOR-treated versus CSDS (NORCSDS) from the prefrontal cortex. These protein expression alterations were first analyzed by ANOVA with p < 0.05. The protein cluster 1 and cluster 3, in which the pattern of protein levels similar to the mood pattern, showed enrichment in functions and localizations related to mitochondrion, ribosome and synapses. Further GO analysis of the common proteins for NORCSDS groups and NORIMI groups supported the findings from ANOVA analysis. We employed Protein-Protein interaction (PPI) analysis to examine the proteins of NORCSDS and NORIMI, revealing an enrichment of the proteins associated with the mitochondrial ribosomal and synaptic functions. Further independent analysis using parallel reaction monitoring (PRM) revealed that Cox7c, Mrp142, Naa30, Ighm, Apoa4, Ssu72, Mrps30, Apoh, Acbd5, and Cdv3, exhibited regulation in the NOR-treated group to support the homeostasis of mitochondrial functions. Additionally, Dcx, Arid1b, Rnf112, and Fam3c, were also observed to undergo modulation in the NOR-treated groups to support the synaptic formation and functions. These findings suggest that the proteins involved in depression treatment exert effects in strengthen the mitochondrial and synaptic functions in the mice PFC. Western blot analysis supported the data that the levels of Mrpl42, Cox7c, Naa30, Rnf112, Dcx Apoa4, Apoh and Fam3c were altered in the CSDS mice, and rescued by NOR treatment, supporting the PRM data. NOR treatment also rescued the NLRP3 inflammasome activation in CSDS mice. In summary, the current proteomic research conducted on the prefrontal cortex has provided valuable insights into the specific and shared molecular mechanisms underlying pathophysiology and treatment to CSDS-induced depression, shedding light on the therapeutic effects of Norisoboldine.

Electroacupuncture attenuates depressive-like behaviors in poststroke depression mice through promoting hippocampal neurogenesis and inhibiting TLR4/NF-κB/NLRP3 signaling pathway.

The aim of this study was to investigate the impact and underlying molecular mechanisms of electroacupuncture on mice with poststroke depression (PSD). Mice were randomly allocated into sham, PSD, and electroacupuncture groups. Mice in the PSD and electroacupuncture groups underwent middle cerebral artery occlusion (MCAO) surgery following with sedentary behavior. Electroacupuncture targeting Zusanli (ST36) acupoint was performed 24 h after MCAO for 4 weeks in electroacupuncture group. The sucrose preference test, forced swimming test, open field test, tail suspension test, elevated plus maze, Catwalk analysis, RNA sequencing, Nissl staining, Golgi staining, TUNEL staining, Edu labeling, and doublecortin staining were performed. Lymphocyte subsets in peripheral blood and the levels of IL-1β, IL-6, TNF-α, and expression of Iba1/CD86, Iba1/NLRP3, TLR4/p38/NF-κB/NLRP3 pathways in the hippocampus were detected. Electroacupuncture effectively protected against the development of depression-like symptoms. The number of granulosa cells and doublecortin-positive cells in the dentate gyrus (DG) were significantly decreased in PSD group, which were significantly upregulated ( P < 0.01) by electroacupuncture. Electroacupuncture also significantly reduced ( P < 0.05) TUNEL-positive cells in the DG and CA1. RNA-seq revealed that electroacupuncture may exert antidepressant effect by regulating the inflammation mediated by TLR4/NF-κB/NLRP3 pathway in hippocampus. Electroacupuncture remarkably elevated ( P < 0.01) the ratio of CD4+ to CD8+ T cells and percentage of CD3-CD49b+ cells in CD45+CD49b+ cells in the peripheral blood. Electroacupuncture significantly reduced ( P < 0.05) the high levels of IL-1β, IL-6, TNF-α, iba1, TLR4, p-p38, p-NF-κB, and NLRP3 and sedentary behavior. Electroacupuncture was observed to mitigate depression symptoms and increase hippocampal neurogenesis in mice with PSD, possibly by inhibiting TLR4/p38/NF-κB/NLRP3 pathways and improving the microglia-mediated inflammatory microenvironment in the hippocampus.

The role of circadian clock gene Arntl in the winter depression-like behavior in melatonin-proficient female CBA/N mice

Seasonal affective disorder (SAD), also known as winter depression, is a subtype of depression typically manifesting in winter. Typical symptoms of SAD, such as an increased need for sleep and carbohydrate cravings associated with increased appetite and weight, are distinct from those of major depression, and the underlying mechanisms of SAD remain unclear. Although laboratory mice are generally considered non-seasonal animals, we observed depression-like behaviors in melatonin-proficient female CBA/N mice maintained under winter-mimicking conditions. Transcriptome analysis of the brains of CBA/N mice maintained under winter- and summer-mimicking conditions revealed changes in the expression of circadian clock genes, including Arntl (also known as Bmal1). We generated Arntl-deficient, melatonin-proficient CBA/N mice using the speed congenic method to examine the role of Arntl in depressive behavior. The tail suspension test in these mice revealed a depressive phenotype. These results suggested that the circadian clock gene Arntl may be involved in winter depression-like behavior.

Xiangshao Granules Ameliorate Post-Stroke Depression by Inhibiting Activation of Microglia and IDO1 Expression in Hippocampus and Prefrontal Cortex.

To investigate the therapeutic effect of Xiangshao Granules (XSG) on post-stroke depression (PSD) and explore the underlying mechanisms. Forty-three C57BL/6J mice were divided into 3 groups: sham (n=15), PSD+vehicle (n=14), and PSD+XSG (n=14) groups according to a random number table. The PSD models were constructed using chronic unpredictable mild stress (CUMS) after middle cerebral artery occlusion (MCAO). The sham group only experienced the same surgical operation, but without MACO and CUMS stimulation. The XSG group received XSG (60 mg/kg per day) by gavage for 4 weeks. The mice in the sham and vehicle groups were given the same volume of 0.9% saline at the same time. The body weight and behavior tests including open field test, sucrose preference test, tail suspension test, and elevated plus-maze test, were used to validate the PSD mouse model. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence staining were used to evaluate the anti-inflammatory effects of XSG. The potential molecular mechanisms were explored and verified through network pharmacology analysis, Nissl staining, Western blot, ELISA, and RT-qPCR, respectively. The body weight and behavior tests showed that MCAO combined with CUMS successfully established the PSD models. XSG alleviated neuronal damage, reduced the expressions of pro-apoptotic proteins Caspase-3 and B-cell lymphoma-2 (BCL-2)-associated X (BAX), and increased the expression of anti-apoptotic protein BCL-2 in PSD mice (P<0.05 or P<0.01). XSG inhibited microglial activation and the expressions of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin (IL)-1 β, and IL-6 via the toll-like receptor 4/nuclear factor kappa-B signaling pathway in PSD mice (P<0.05 or P<0.01). Furthermore, XSG decreased the expression of indoleamine 2,3-dioxygenase1 (IDO1) and increased the concentration of 5-hydroxytryptamine in PSD mice (P<0.05 or P<0.01). XSG could reverse the anxiety/depressionlike behaviors and reduce the neuronal injury in the hippocampus and prefrontal cortex of PSD mice, which may be a potential therapeutic agent for PSD.

Atractylenolide-I Ameliorates Motor Deficits and Reduces Inflammation of the Spinal Cord by SIRT1/PGC-1α Pathway in MPTP Subacute Mouse Model of Parkinson's Disease.

Parkinson's disease (PD) is a neurodegenerative movement disorder that impacts various systems, including the substantia nigra (SN) par compacta (SNpc) and extranigral regions like the spinal cord. The presence of persistent inflammation in the SN and spinal cord is associated with movement difficulties in PD. Atractylenolide-I (ATR-I) is a natural sesquiterpene recognized for its anti-inflammatory and neuroprotective effects. This research aimed to assess the impact of ATR-I treatment on motor function and inflammation in MPTP-induced subacute PD mice, particularly focusing on the role of ATR-I in spinal cord inflammation. The motor functions of the mice were assessed using suspension and gait tests. Dopaminergic neuronal loss in the SNpc and microglial activation in both the SNpc and spinal cord were evaluated through immunofluorescence staining. The levels of inflammatory mediators in the spinal cord were measured using RT-qPCR analysis. The expressions of SIRT1 and PGC-1α in the spinal cord were analyzed through Western blotting and RT-qPCR. ATR-I treatment improved motor deficits in MPTP-induced mice. Moreover, ATR-I reduced the loss of dopamine neurons and microglial activation in the SNpc of MPTP-induced mice. Additionally, ATR-I suppressed spinal cord inflammation by decreasing microglial activation and the mRNA expression of TNF-α, IL-1β, and iNOS in MPTP-induced mice. Interestingly, ATR-I also upregulated SIRT1 and PGC-1α levels in the spinal cord of MPTP-induced mice. These findings suggest that ATR-I exhibits anti-inflammatory and neuroprotective properties in PD. The attenuation of spinal cord inflammation via the SIRT1/PGC-1α pathway may contribute to enhancing motor function, highlighting ATR-I as a potential therapeutic avenue for PD.

Overexpression of ATF4 Inhibits Ferroptosis to Alleviate Anxiety Disorders by Activating the TGF-β Signaling Pathway.

Anxiety disorders seriously impair patients' mental health and quality of life, with limited effectiveness of current treatments. Dysregulation of activating transcription factor 4 (ATF4) is involved in various mental diseases, but the research on its potential roles in alleviating anxiety disorders remains limited. ATF4 was screened out by bioinformatic analysis and its expression was verified in vivo. Mice were treated with 21 d of chronic restraint stress to establish the anxiety mice model. The anxiolytic effect of ATF4 was assessed by a battery of behavior tests and evaluation of hippocampal tissue damage after overexpressing ATF4. Ferroptosis-related indicators were detected by enzyme-linked immunosorbent assay and Western blotting. Then the transforming growth factor beta (TGF-β) signaling pathway was predicted as the downstream regulatory pathway of ATF4 by bioinformatic methods. Western blotting was conducted to detect the protein expression level of TGF-β1, small mothers against decapentaplegic 3 (Smad3), and phospho-Smad3 (p-Smad3). ATF4 was screened out as a ferroptosis-related anxiolytic gene after bioinformatics analysis and was down-regulated in the anxiety mice model. Mice with ATF4 overexpression spent more time in the open arms in the elevated plus-maze test, appeared more frequently in the central area in the open-field test, and decreased the immobility time in the forced swimming and tail suspension tests. Hippocampal tissue damage was alleviated, ferroptosis was suppressed, and the levels of TGF-β1 and p-Smad3/Smad3 were increased by AFT4 overexpression. ATF4 overexpression can repress ferroptosis to improve anxiety disorders by activating the TGF-β signaling pathway.

Effects of E2 on the IDO1-mediated metabolic KYN pathway in OVX female mice.

The aim of this study was to investigate the role of 17β-estradiol (E2)-mediated oestrogen receptor (ER) in modulating the depressive-like behaviours of ovariectomy (OVX) mice and the associated mechanisms. E2 was administrated in OVX mice. The behaviour and physiological changes of OVX mice including immobility time in tail suspension test (TST) and forced swimming test (FST), levels of serum E2, inflammatory mediators, oxidative stress factors, indoleamine2,3-dioxygenase 1 (IDO1) and the neurotransmitters mediated by IDO1 activation were then recorded. Cell injury models established by lipopolysaccharide (LPS) or H2O2 stimulation in HT22 and BV2 cells were employed to further explore the mechanisms of E2's function. E2 treatment improved OVX-induced increase of immobility time in FST and TST. Meanwhile, E2 ameliorated the changes of inflammatory factors (NF-κB, TNF-α and IL-6), IDO1, IDO1-mediated TRP/KYN pathway and oxidative stress factors (iNOS, MDA, GSH and SOD) in the hippocampus of OVX mice. Interestingly, ERβ inhibitor abolished E2's inhibitory effects on the inflammation and IDO1-mediated TRP/KYN pathway; ERβ inhibitor also abolished E2's anti-oxidative stress effect. In cell experiments, ERβ small interfering RNA (siRNA) pretreatment reversed E2's anti-inflammatory effect on LPS-treated HT22 and BV2 cells and E2's inhibitory effect on IDO1 expression in LPS-treated BV2 cells. ERβ siRNA pretreatment also reversed E2's anti-oxidation effect on H2O2-treated HT22 cells. E2 exert the antidepressant function in OVX mice via ERβ-modulated suppression of NF-κB-mediated inflammatory pathway, oxidative stress factors and IDO1-mediated TRP/KYN pathway in the hippocampus.

Prebiotic inulin alleviates anxiety and depression-like behavior in alcohol withdrawal mice by modulating the gut microbiota and 5-HT metabolism

BackgroundAlcohol dependence (AD) is a common psychiatric disorder, often accompanied by anxiety and depression. These comorbidities are linked to disturbances in serotonin (5-HT) metabolism and gut microbiota dysbiosis. Clinical studies suggest that inulin, a prebiotic, can alleviate anxiety and depression in AD patients by affecting the gut microbiota, although the mechanisms remain unclear. PurposeThe purpose of this study is to investigate the potential mechanisms by which inulin, a prebiotic, improves anxiety and depression-like behaviors in AD withdrawal mice. This research is based on the drug and food homology and intestinal treatment of encephalopathy, with the goal of developing new clinical strategies for AD treatment. Study DesignFor this purpose, fecal samples from AD patients were analyzed to identify microorganisms associated with AD. An AD withdrawal mouse model was created, with inulin as the intervention and fluvoxamine maleate as the control. Techniques such as 16S microbiome sequencing and UPLC-TQMS-targeted metabolomics were used to assess gut microbiota, short-chain fatty acids (SCFAs) levels, and 5-HT metabolism. MethodsThe AD withdrawal model was built using the "Drinking-in-the-dark" protocol over 6 weeks. Inulin (2 g/kg/day) and fluvoxamine maleate (30 mg/kg/day) were administered for 4 weeks. The open field test, forced swim test, and tail suspension test were used to evaluate anxiety and depression-like behaviors in mice. ELISA and qRT-PCR assessed 5-HT metabolism in the colon, blood, and prefrontal cortex, while 16S microbiome sequencing analyzed changes in gut microbiota and UPLC-TQMS examined SCFAs levels. Immunohistochemistry was used to study intestinal barrier integrity. ResultsAD patients showed reduced SCFA-producing bacteria such as Faecalibacterium and Roseburia. In mice, AD withdrawal led to anxiety, depression-like behaviors, disrupted 5-HT metabolism, and gut microbiota dysbiosis. Inulin supplementation alleviated these behaviors, increased 5-HT and 5-hydroxytryptophan (5-HTP) levels, upregulated colonic tryptophan hydroxylase 1 (TPH1) expression, and promoted the growth of beneficial bacteria such as Faecalibacterium and Roseburia, while also increasing SCFAs levels. ConclusionInulin increases the abundance of Faecalibacterium and Roseburia, enhances SCFAs production, and regulates 5-HT metabolism, improving anxiety and depression-like behaviors in AD withdrawal mice. These findings suggest that inulin may serve as a nutritional intervention for mental health in AD patients by targeting the microbiome-gut-brain axis.

Visual analysis of research hotspots and trends in traditional Chinese medicine for depression in the 21st century: a bibliometric study based on Citespace and VOSviewer

Background and ObjectivesDepression long been a key concern for scholars worldwide; however, the field of depression has not received sufficient attention in traditional Chinese medicine. It was not until the 21st century that research into depression gradually entered a period of rapid development, with an increasing number of academic studies published in major journals. However, one limitation of this field is that no scholars have yet summarised the development process and key research issues. Therefore, the present study aimed to summarise the research trends and progress in this field, providing relevant information and presenting potential future research directions for subsequent researchers. MethodsLiterature in this field was searched from 1 January 2000 to 20 April 2024 in the Web of Science Core Collection database, to analyse the current status of the literature and publication trends. Bibliographic information, including study authors, organisations, keywords, countries, references, citations, and co-citations, was extracted using CiteSpace and VOSviewer software for quantitative analysis, visual mapping, and scientific evaluation. ResultsA total of 921 papers were included, with a significant increase in the number of publications from 2017 to 2021, and a stable number of more than 140 publications between 2022 and 2023, with publications in these two years accounting for 31.38% of the total. The Journal of Ethnopharmacology had the highest number of publications (97) and citations (2067), as well as the highest number of co-citations (1369). China (847 publications, 13256 citations), Beijing University of Chinese Medicine (90 publications, 1232 citations), and Qin Xuemei (30 publications, 759 citations) were the most prolific and influential countries, organisations, and authors in the field, respectively. Keyword clustering co-occurrence analysis revealed nine different clusters with good homogeneity. The top three clusters were randomised controlled trials, traditional Chinese medicine, and hippocampal neurogenesis. In the timeline analysis of keywords, from 2000 to 2010, keywords in this field were concentrated on hippocampal neurology and forced swimming test as clustering axes of Traditional Chinese Medicine. From 2010 to 2020, the research hotspots focused on randomised controlled trials and hippocampal neurogenesis. After 2020, keywords became more focused on network pharmacology. In addition, the occurrence time of explosive keywords were distributed before 2010 and after 2020. Before 2010, these keywords included the forced swimming test, Tail Suspension Test, Chronic Cold Stress, Neural Regeneration, and Banxia Houpu Decoction. Conversely, network Pparmacology and Molecular Docking arose as key buzzwords starting in 2020. ConclusionsThis study comprehensively analysed and summarised the research hotspots and trends in this field of research in the 21st century from a bibliometric perspective, further generating a series of visual graphs to help researchers understand the current research status, potential collaborators, collaborating institutions, and potential future research hotspots in this field.

Yap1 alleviates sepsis associated encephalopathy by inhibiting hippocampus ferroptosis via maintaining mitochondrial dynamic homeostasis.

Sepsis-associated encephalopathy (SAE) is a serious neurological complication accompanied by acute and long-term cognitive dysfunction. Ferroptosis is a newly discovered type of cell death that is produced by iron-dependent lipid peroxidation. As a key transcriptional coactivator in the Hippo signalling pathway, Yes-associated protein 1 (YAP1) could target ferroptosis-related genes. This study was aimed to determine whether Yap1 protects against SAE and inhibits ferroptosis via maintaining mitochondrial dynamic homeostasis. Caecal ligation puncture (CLP) was used to establish the SAE model, and LPS was applied in hippocampal cells to mimic the inflammatory model invitro. The results showed that Yap1 conditional knockout in hippocampal caused lower survival in SAE mice and cognitive dysfunction, as proved by Morri's water maze (MWM) task, tail suspension test (TST), open field test (OFT) and elevated plus maze test (EPMT). After Yap1 knockout, the production of ROS, MDA and Fe2+ and proinflammatory cytokines in the hippocampus were increased, indicating that Yap1 deficiency exacerbates CLP-induced brain injury and hippocampus ferroptosis. Meanwhile, GPX4, SLC7A11, ferritin (FTH1) and GSH levels were decreased in the Yap1 knockout group. Invitro, Yap1 overexpression mitigated LPS-induced hippocampal cell ferroptosis and improved mitochondrial function by inhibiting mitochondrial fission, as evidenced by lower mitochondrial ROS, cell viability, Fe2+ and the expression of Fis1 and Drp1. Further, the present study suggested that Yap1 could inhibit ferritinophagy-mediated ferroptosis in the hippocampus via inhibiting mitochondrial fission, thus reducing cognitive dysfunction in SAE mice.

Chronic unpredictable stress during adolescence exerts sex-specific effects on depressive-like behavior and neural activation triggered by tail suspension test

During adolescence, acute stress can modify neuronal excitability in various brain regions, leading to negative behavioral outcomes. However, the impact of chronic stress during adolescence on neuronal responses to acute stimuli remains unclear. To address this, we subjected adolescent mice to 12 days of chronic unpredictable stress (CUS). Anxiety and depressive behaviors were evaluated, along with changes in c-Fos expression, which is one of the most widely used markers of neuronal activation. By comparing c-Fos immunoreactivity between the CUS and control groups both before and after the tail suspension test (TST), we found that adolescent CUS induced depressive behaviors in male mice, but not in female mice. Adolescent CUS primarily affected the excitability of neurons in the infralimbic cortex (IL), the dorsomedial and dorsolateral area of the bed nucleus of the stria terminalis (BNST), and the ventral hippocampus CA3. TST exerted a significant main effect on the density of c-Fos+ neurons in the prelimbic cortex (PL), infralimbic cortex (IL), cingulate areas 1 and 2 (Cg1, Cg2), the lateral septum (LS), Bed nucleus terminalis (BNST), and lateral habenular (LHb). Furthermore, the excitability of neurons in the paraventricular thalamic nucleus (PVT) was impacted by sex. These data suggest that adolescent CUS elicits region- and sex-specific modifications in TST-induced c-Fos expression, establishing a theoretical basis for understanding the pathophysiological alterations in mood disorders following adolescent stress.

The Interplay between MiR-134/BDNF and LKB1/AMPK/SIRT1 Accentuates the Antidepressant Efficacy of Empagliflozin in Ovariectomized Rats.

Major depressive disorder (MDD) is considered a major cause of suicide worldwide. As previous studies revealed that neuroinflammation is a significant factor in the etiology of MDD, this study proposed to unravel the possible antidepressant effect of Empagliflozin (EMPA) through targeting miRNA-134 (miR-134)/brain-derived neurotrophic factor (BDNF) and liver kinase B1 (LKB1)/adenosine 5'-monophosphate-activated protein kinase (AMPK)/silent information regulator 1 (SIRT1) axes in ovariectomized (OVX) female rats. Rats were assigned randomly to four groups: Sham operation (SO), OVX, OVX + EMPA (10 mg/kg/day, p.o.), and OVX + EMPA + Dorsomorphin (DORSO) (25 μg/day/rat, i.v.). Drugs were administered for 28 days after 2 weeks of surgery. EMPA debilitated OVX-induced depressive-like behavior by mitigating the immobility time in the tail suspension test and forced swimming test. Moreover, EMPA curtailed OVX-induced alterations of serum estradiol, hippocampal serotonin, miR-134 expression, as well as BDNF. EMPA also dwindled OVX-induced changes of hippocampal p-LKB1/LKB1, p-AMPK/AMPK, SIRT1, and inflammatory markers (nuclear factor-kappa-B, interleukin-1 beta, interleukin-6, and tumor necrosis factor alpha). Additionally, the EMPA-treated group exhibited marked improvement in different brain regions' histopathology. However, DORSO coadministration reversed most of EMPA's beneficial effects. The current study displayed the modulatory role of EMPA on miR-134/BDNF and LKB1/AMPK/SIRT1 axes, thus offering a partial explanation of its antidepressant efficacy and proposing EMPA as a novel therapeutic avenue for MDD.

Salidroside exerts antidepressant-like action by promoting adult hippocampal neurogenesis through SIRT1/PGC-1α signalling.

Depression is one of the major mental disorders, which seriously endangers human health, brings a serious burden to patients’ families. In this study, we intended to further explore the antidepressant-like effect and possible molecular mechanisms of Salidroside (SAL). We built corticosterone (CORT)-induced depressive mice model and used behavioural tests to evaluate depression behaviour. To explore the molecular mechanisms of SAL, we employed a variety of methods such as immunofluorescence, western blot, pharmacological interference, etc. The results demonstrated that SAL both at 25 mg/kg and 50 mg/kg can reduce immobility time in the tail suspension test (TST). At the same time, SAL treatment could restore the reduced sugar water intake preference in the sucrose preference test (SPT) in CORT-induced depressive mice and reduce the immobility time in TST and forced swimming experiments (FST). In addition, SAL treatment reversed the reduction in the number of Ki-67, BrdU, and NeuN in the hippocampus due to CORT treatment. SAL treatment also restored the expression of SIRT1, PGC-1α, brain-derived neurotrophic factor (BDNF) and other proteins in the hippocampus. In addition, after blocking SIRT1 signalling with EX527, we found that the treatment with SAL failed to reduce the immobility time in TST and FST, the level of SIRT1 and PGC-1α activity were correspondingly downregulated, and the expression of DCX and Ki-67 in the hippocampus failed to be activated. These findings suggested that SAL exerts antidepressant-like effects by promoting hippocampal neurogenesis through the SIRT1/PGC-1α signalling pathway.