Search Results (78)

Depression is increasingly linked to microbiota–gut–brain axis dysfunction, yet current monoaminergic antidepressants show limited efficacy. This study investigated the therapeutic potential and underlying mechanisms of GV-971, a marine-derived oligosaccharide, in a chronic restraint stress (CRS) mouse model. We first established that 8 h of daily restraint for 4–8 weeks induces a stable depression-like phenotype characterized by behavioral despair and significant reduction in peripheral monoamine neurotransmitters (5-HT and norepinephrine). GV-971 treatment robustly attenuated CRS-induced depression- and anxiety-like behaviors, restored hippocampal serotonin levels, reduced elevated plasma corticosterone concentrations, and ameliorated CRS-induced adrenal cortical hyperplasia. Mechanistically, GV-971 significantly suppressed neuroinflammation by inhibiting microglial hyperactivation in the prefrontal cortex and hippocampus. Concurrently, it repaired intestinal barrier dysfunction, evidenced by reduced permeability, restored mucosal integrity, and recovered goblet cell numbers. Crucially, integrated shot-gun metagenomics and plasma metabolomics revealed that GV-971 not only reshaped microbial taxonomy but also functionally recalibrated the gut ecosystem. It enriched beneficial taxa (e.g., Bifidobacterium pseudolongum, Bacteroides uniformis) and specific metabolic pathways, leading to increased short-chain fatty acids (valeric and caproic acids) and a significant reduction in plasma levels of tryptophan–kynurenine pathway metabolites, specifically the neurotoxic compounds kynurenine and quinolinic acid. Fecal microbiota transplantation (FMT) from GV-971-treated donors partially recapitulated the antidepressant and gut-protective effects in CRS recipients, confirming a causal role for the remodeled microbiota. Collectively, GV-971 exerts antidepressant effects by coordinately remodeling the gut microbiota, normalizing tryptophan and SCFA metabolism, restoring gut barrier integrity, and dampening central neuroinflammation, supporting its potential as a novel gut–brain axis-targeted therapy for depression. Full article

Bergamot essential oil (BEO) has demonstrated antidepressant potential, but its oral application is limited by poor water solubility and undesirable organoleptic properties. In this study, a BEO-loaded beverage was developed based on a whey protein-stabilized oil-in-water emulsion system. The optimal formulation, determined via single-factor experiments combined with orthogonal optimization, consisted of inulin (0.5 g/50 g), milk powder (2.0 g/50 g), sucralose (0.008 g/50 g), and sodium carboxymethyl cellulose (0.04 g/50 g). The resulting beverage remained stable without visible phase separation during 4 months of storage at 4 °C. In a chronic corticosterone treatment (CCT)-induced mouse model of depression, oral administration of the BEO beverage increased activity in the central area of the open field test and exploratory behavior in the elevated plus maze, while reducing repetitive stereotyped behaviors in the marble burying test. At the molecular level, the BEO beverage was associated with reduced levels of interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and corticosteroid (CORT), and increased levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), serotonin (5-HT), dopamine (DA), and norepinephrine (NE). Additionally, the BEO beverage was associated with observed alleviation of neuronal damage in the hippocampal CA3 region, upregulation of brain-derived neurotrophic factor (BDNF), improved gut microbial diversity, and altered host metabolic profiles. Collectively, these findings suggest that the BEO emulsion beverage is a feasible intervention for alleviating depression-like behaviors in the mouse model, and provide initial associative evidence supporting its potential as a functional food for mood management. Full article

Background: Chronic unpredictable stress triggers various pathological and metabolic alterations by modulating psychophysiological balance. Valeric acid (VA), a postbiotic material, has been reported to mitigate stress-induced behavioral changes in rodents. Objectives: To investigate the protective effect of valeric acid against chronic unpredictable stress in a rodent model by assessing neuro-physiological alterations along with changes in biochemical parameters to confirm the possible mechanism. Methods: A 14-day chronic unpredictable stress (CUS) model in albino Wistar rats was developed to check the stress-induced changes using forced swim test, tail suspension test and sexual behavior observation. Quantification of IL-6, TNF-α, IL-1β, plasma corticosterone level and oxidative stress parameters were also done. Results: Findings revealed the protective effects of valeric acid against CUS, which reversed the depression caused by a forced swim and tail suspension test in rats. Proinflammatory and oxidative stress markers were significantly (p < 0.05) restored in CUS rats treated with valeric acid as compared with the vehicle control, which was comparable to the standard drug, Panax ginseng. Conclusions: The present study concludes that valeric acid demonstrated significant (p < 0.05) anti-stress effect by modulating both behavioral responses and stress-related biochemical modifications. Full article

Chronic stress and sustained hypothalamic–pituitary–adrenal (HPA) axis activation are major contributors to metabolic bone diseases, including osteoporosis. However, the precise molecular mechanisms by which chronic stress-induced HPA axis dysregulation drives bone deterioration remain unclear. A Chronic Unpredictable Mild Stress (CUMS) model was established in male rats to simulate prolonged stress exposure. Animals were randomly allocated into three groups: control, 10-week CUMS, and 20-week CUMS (n = 10/group). Model validity was confirmed via behavioral assessments. Bone mineral density (BMD) and trabecular microarchitecture were quantified using micro-computed tomography (micro-CT). Serum corticosterone (CORT) levels, HPA axis negative feedback function, and the expression of pro-inflammatory cytokines (IL-1β, TNF-α) in HPA-regulatory brain regions (hippocampus, prefrontal cortex, hypothalamus) were assessed. Critically, glucocorticoid receptor (GR) expression and nuclear translocation in these brain regions and bone tissue were examined by immunofluorescence and Western blot analysis. CUMS exposure induced progressive, time-dependent bone loss, with the 20-week group exhibiting significantly greater reductions in BMD and trabecular quality compared to the 10-week and control groups. While the HPA axis showed initial hyperactivation, the 20-week group displayed adrenal exhaustion (reduced serum CORT) alongside elevated ACTH, indicating feedback failure. Mechanistically, stress significantly impaired GR nuclear translocation in both brain and bone tissues, coinciding with the upregulation of FKBP5 and pro-inflammatory cytokines. Notably, despite low systemic CORT at late stages, skeletal 11β-HSD1 expression was significantly upregulated, creating a local microenvironment of glucocorticoid toxicity that aggravated osteoblast apoptosis. Our findings demonstrate that chronic stress induces progressive, time-dependent bone loss through a cascade of HPA axis dysregulation and impaired GR signaling. The FKBP5-mediated impairment of GR nuclear translocation in both central and peripheral tissues fosters glucocorticoid resistance, perpetuating hypercortisolemia and a pro-inflammatory milieu that directly accelerates osteoblast apoptosis and bone deterioration. These findings identify the HPA-GR axis as a critical pathway linking chronic stress to osteoporosis and suggest that restoring GR signaling offers a potential therapeutic strategy. Full article

Sex differences in stress response continue to be understudied in basic physiological and behavioral research. The current study aimed to investigate the sex-specific effects of chronic stress in wild-derived house mice subjected to chronic unpredictable stress (CUS). The use of wild-derived mice enhanced the ecological validity of our stress model. We applied CUS for 5 weeks based on protocols previously established in laboratory mice, with regular weighting and welfare checks. Control mice were not subjected to stress. After the 5-week exposure, behavioral tests were performed, blood and hair samples were collected for corticosterone measurement, and stress-sensitive organ weights were assessed. Stressed females, but not stressed males, gained significantly less body weight over the entire CUS period. After CUS, mice tended to have higher adrenal and thymus weights. In stressed females, we observed significantly prolonged grooming time in the open field test and fewer immobility episodes in the tail suspension test (TST). Stressed males displayed significantly shorter immobility time in TST. Stressed males, but not stressed females, had significantly higher levels of hair corticosterone, with a similar tendency in plasma. Our results indicate different CUS coping strategies in males and females and raise a question about the development of different protocols for the assessment of stress responses in males and females. Full article

The resin extract of Garcinia nigrolineata (GNR-E), a tropical plant used in Southeast Asian traditional medicine, was evaluated for its antidepressant-like effects in a chronic mild stress (CMS) mouse model, with imipramine as a reference drug. GNR-E dose-dependently alleviated CMS-induced anhedonia (sucrose preference test) and behavioral despair (forced swimming and tail suspension tests). Neurochemical analyses revealed that GNR-E increased serotonin (5-HT) and norepinephrine (NE) levels, reduced expression of their transporters (SERT, NET) and receptors (5-HT1A, 1B, 2A, 2C, 7; α2A, 2C) in the frontal cortex and hippocampus, and normalized HPA-axis hyperactivity by lowering serum corticosterone and modulating glucocorticoid receptor (GR) and SGK-1 mRNA expression. In vitro, GNR-E inhibited monoamine oxidase (MAO)-A and -B (Ki = 2.33 and 1.55 µg/mL, respectively). Phytochemical analysis identified xanthones, particularly cowanin, as key constituents. These findings highlight GNR-E’s potential as a novel plant-based antidepressant, warranting further investigation into its active compounds and clinical applications. Full article

Stress is a predisposing factor for pulmonary diseases; however, its effects on the lungs of healthy individuals have not been fully elucidated. Since bovine lactoferrin (bLf) is a powerful immunomodulator, this study aimed to evaluate whether lactoferrin can modulate the effects of chronic stress on humoral and cellular immunity in the lungs. We performed chronic restraint stress (RS) and oral administration of bLf in a BALB/c model, assessing serum corticosterone, body weight, and various lung immunity parameters, including immunoglobulin concentrations in serum and tracheobronchial lavages (TBLs), secretory IgA (S-IgA) levels in TBLs, IgA-secreting plasma cells, relative expression of pIgR, CD4⁺ lymphocyte Th1 and Th2 populations, and antigen-presenting cell (APC) populations in the lungs. Our results demonstrate that stress increases corticosterone and production of total IgA and IgG, while decreasing levels of IgM and S-IgA, promotes a Th1/Th2 profile imbalance, and decreases APC populations. Interestingly, bLf modulates serum corticosterone levels and stress-induced weight loss, and it also modulates humoral and cellular effects produced by chronic stress. These results demonstrate that bLf should be considered a new therapeutic target for further studies, focusing on prophylactic and co-therapeutic administration to treat and prevent respiratory diseases. Full article

Gulf War illness (GWI) is a multi-symptom disorder affecting veterans of the Persian Gulf operations. Persistent neuroendocrine dysregulation contributes to impairing cognitive capacity and generates anxiety-like behavior. Effective treatments for this illness are challenging due to compromised metabolism, increased oxidative stress and neuroinflammation, perpetuated by chronic stress and hypothalamic–pituitary–adrenal (HPA) axis dysfunction. This neuroinflammation can be alleviated with synthetic antagonistic analogs of the growth hormone-releasing hormone (GHRH) through modulation of the HPA axis. We evaluated the efficacy of the GHRH antagonist analog, MIA-690, against cognitive impairment and anxiety-like behavior in GWI. Mice exposed to an experimental GWI model involving corticosterone (CORT) and diisopropylfluorophosphate (DFP), followed by CORT and lipopolysaccharide (LPS), received a daily subcutaneous dose of 10 μg of MIA-690 for 10 days. Assessments of spatial memory, recognition capacity, somatic health, anxiety and innate survival were carried out, combining the Morris water maze (MWM), novel object recognition (NORT), grip strength (GST), and open field (OFT) tests. Learning efficiency was selectively enhanced in females using the MWM. There were no significant differences in the recall capacity and performance on the OFT, NOR, and GST tasks. Our findings suggest that the MIA-690 dosage is sufficient to improve learning deficits in experimental GWI exposures. Full article

Background/Objectives: Urolithin A (UA), a gut-derived metabolite of ellagitannins or ellagic acid, has recently gained attention for its potential benefits to brain health. The present research aimed to assess the antidepressant-like properties of UA in both in vitro and in vivo models and explored the molecular mechanisms underlying these effects. Methods: We investigated the antidepressant effects and mechanisms of UA in a model of corticosterone-induced damage to PC12 cells and in a model of chronic socially frustrating stress. Results: Our results demonstrate that UA treatment (5 and 10 μM) significantly alleviated cellular damage and inflammation in corticosterone (CORT)-treated PC12 cells. Furthermore, UA administration (50 and 100 mg/kg) significantly reduced immobility time in the mouse tail suspension test (TST) and forced swim test (FST), indicating its antidepressant-like activity. Additionally, treatment with UA led to the activation of the cAMP response element-binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling cascade and triggered the activation of adenosine monophosphate-activated protein kinase (AMPK) during these processes. Importantly, pretreatment with AMPK-specific inhibitor Compound C abolished UA’s cytoprotective effects in PC12 cells, as well as its behavioral efficacy in the FST and TST, and its neurotrophic effects, highlighting the critical role of AMPK activation in mediating these effects. Furthermore, in the chronic social defeat stress (CSDS) mouse model, UA treatment (50 and 100 mg/kg) significantly alleviated depression-like behaviors, including reduced sucrose preference in the sucrose preference test, increased social avoidance behavior in the social interaction test, and anxiety-like behaviors, including diminished exploration, in the elevated plus maze test, suggesting the antidepressant-like and anxiolytic-like activities of UA. Moreover, UA treatment reversed elevated serum stress hormone levels, hippocampal inflammation, and the decreased AMPK/CREB/BDNF signaling pathway in the hippocampus of CSDS mice. Conclusions: Together, these results provide compelling evidence for UA as a viable dietary supplement or therapeutic option for managing depression. Full article

Behavioral stress is a recognized triggering factor for systemic diseases, including psychiatric disorders. The stress response is subjected to circadian regulation and many factors shape the susceptibility to its maladaptive consequences, including the biological sex. Accordingly, circadian dysregulation of the stress response, often occurring in a sexually dimorphic manner, is typically associated with psychiatric disorders. However, the interaction between stress, sex, circadian phases, and behavior is still largely unknown. Here, we used the chronic restraint stress (CRS) model in male and female mice to assess the impact of sex and circadian phases on the behavioral consequences of chronic stress. Animals were stressed either in the light or dark phase, and anxious-/depressive-/anhedonic-like behaviors were assessed. Associated transcriptional changes in clock genes were measured in the prefrontal cortex. A significant interaction of stress, sex, and circadian phase was found in most of the parameters evaluated, with no behavioral response to stress in males stressed in the dark phase, and an exaggerated response in females stressed in the dark phase compared to the light phase. We also found some molecular changes in corticosterone serum levels and expression of clock genes in the prefrontal cortex. Full article

Background/Objectives: Dimethyl trisulfide (DMTS) is a naturally occurring polysulfide with known antioxidant and neuroprotective properties. DMTS is a lipophilic transient receptor potential ankyrin 1 (TRPA1) ligand that reaches the central nervous system (CNS). Its role in the CNS, particularly regarding depression-like behaviour, has yet to be explored. This study investigates the influence of DMTS on stress responses and whether this effect is mediated through the TRPA1 ion channel, known for its role in stress adaptation. Using a mouse model involving three-week exposure, we examined the impact of DMTS on depression-like behaviour and anxiety and identified the involved brain regions. Methods: Our methods involved testing both Trpa1-wild-type and gene-knockout mice under CUMS conditions and DMTS treatment. DMTS was administered intraperitoneally at a dose of 30 mg/kg on days 16 and 20 of the 21-day CUMS protocol—in hourly injections seven times to ensure sustained exposure. Various behavioural assessments—including the open field, marble burying, tail suspension, forced swim, and sucrose preference tests—were performed to evaluate anxiety and depression-like behaviour. Additionally, we measured body weight changes and the relative weights of the thymus and adrenal glands, while serum levels of corticosterone and adrenocorticotropic hormone were quantified via ELISA. FOSB (FBJ murine osteosarcoma viral oncogene homolog B) immunohistochemistry was utilised to assess chronic neuronal activation in stress-relevant brain areas. Results: Results showed that CUMS induces depression-like behaviour, with the response being modulated by the TRPA1 status and that DMTS treatment significantly reduced these effects when TRPA1 channels were functional. DMTS also mitigated thymus involution due to hypothalamic–pituitary–adrenal (HPA) axis dysregulation. Conclusions: Overall, DMTS appears to relieve depressive and anxiety symptoms through TRPA1-mediated pathways, suggesting its potential as a dietary supplement or adjunct therapy for depression and anxiety. Full article

Oxidative stress and membrane damage are believed to be principally involved in the pathogenesis of epilepsy. This study aimed to assess the effects of phenosanic acid (PA), an antioxidant and membrane protector, in acute pentylenetetrazole and chronic lithium–pilocarpine seizure models in male Wistar rats. PA was administered acutely (ip, 120 mg/kg BW ip, or 240 mg/kg BW per os) or chronically (80 mg/kg BW/day per os). Indices of free radical oxidation, the hypothalamo–pituitary–adrenocortical axis, and the nitrergic system were assessed in blood and brain regions. Morphological analysis of the hippocampus was performed in the lithium–pilocarpine model. PA exerted an acute anti-seizure effect in the pentylenetetrazole model. In the lithium–pilocarpine model, acute PA treatment decreased the death rate and corticosterone levels in the neocortex and brainstem. In contrast, the level of free radical oxidation products reacting with thiobarbituric acid declined in the brain stem in response to chronic PA treatment. In the lithium–pilocarpine model, the neuronal density in the dentate gyrus was elevated, and the proliferating cell nuclear antigen positive (PCNA+) cell counts in the subgranular zone did not differ between groups. Doublecortin positive (DCX+) cell count was significantly increased after chronic PA treatment. PA-induced reduction in mortality in the lithium–pilocarpine epilepsy model may be partially mediated by decreasing the lipid peroxidation and corticosterone levels in different brain regions. Chronic PA treatment may affect adult hippocampal neurogenesis by either prolonging the action of factors that increase neurogenesis after status epilepticus or by slowing down the neuronal differentiation rate. These data suggest that PA may be a disease-modifying AED able to hamper epileptogenesis. Full article

Chronic stress can lead to nervous system dysfunction and depression-like behaviors in animals. Gypenosides can improve chronic stress-induced neuronal damage, but the protective mechanism remains poorly understood. This study aims to investigate the effect and mechanism of gypenosides on chronic stress-induced neuronal ferroptosis. Therefore, we established a chronic stress-induced neuronal damage model in vitro using corticosterone to induce PC12 cell injury. We demonstrated that ferroptosis inhibitors DFO and Ferrostatin-1 alleviated corticosterone-induced cell death in PC12 cells by reducing iron accumulation, lipid peroxidation, and increasing cell viability. Meanwhile, gypenosides attenuated ferroptosis agonist Erastin-induced ferroptosis in PC12 cells. Then, gypenosides ameliorated corticosterone-induced ferroptosis in PC12 cells. In terms of molecular mechanisms, gypenosides decreased the expression of Hepcidin and DMT1, and increased the expression of Ferritin and FPN1, thereby improving corticosterone-induced iron homeostasis disorders and iron accumulation. Moreover, gypenosides improved corticosterone-induced lipid peroxidation by inhibiting GLS2 expression, upregulating the expression of SLC7A11 and glutathione peroxidase 4, and reducing glutamate accumulation and GSH depletion. Gypenosides also reduced corticosterone-induced release of inflammatory cytokines, the expression of TNFR1, and the phosphorylation of NF-κB and p53 in PC12 cells. These findings indicate that gypenosides attenuate corticosterone-induced ferroptosis by inhibiting TNF-α/NF-κB signaling pathway in PC12 cells. Full article

Background: Depression is a common psychiatric disorder that may be caused by dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis. The glucocorticoid receptor (GR) plays a significant role in regulating this axis. One negative regulator of GR action, previously associated with depressive behavior, is the overexpression of FK506-binding protein 5 (FKBP5), which may be regulated by microRNAs, including miR-511-5p. Objectives: In a rat model of depression, we aimed to investigate the expression of Fkbp5 and its regulator, miRNA-511-5p, during short- and long-term lithium treatment in four brain regions: the hypothalamus, hippocampus, pituitary, and frontal cortex. Methods: We used a rat model of depression induced by chronic mild stress (CMS) to assess if short- and long-term lithium treatment (7 and 42 days) influences Fkbp5 expression in the brain. We also assessed the effects of lithium treatment on the blood levels of corticosterone in CMS-exposed rats as compared to control groups. The changes in the expression of Fkbp5 were assessed by qPCR and Western blot. The expression of rno-miR-511-5p was assessed using qPCR. Statistical analysis was conducted in GraphPad Prism 9. Results: We found that long-term lithium treatment increased the expression of the FKBP5 protein in the pituitary gland in the lithium-treated rats compared to the control group. We also observed significant changes in Fkbp5 mRNA levels between CMS-exposed rats compared to the control animals, without significant changes in mRNA levels observed during short- and long-term lithium treatment in any brain region. We found no expression of rno-miR-511-5p in the analyzed brain regions. The corticosterone levels were significantly higher in CMS-exposed rats compared to the control, with no significant changes found between lithium-treated and control rats. Conclusions: FKBP5 protein expression in the brain may be regulated by long-term lithium treatment, thus affecting GR signaling in the rat depression model. Full article

Background: This study investigates the neuroprotective effects of 1,8-cineole (1,8-CH), against hippocampal oxidative stress in a chronic unpredictable mild stress (CUMS) mice model of depression, focusing on the underlying molecular mechanisms. Methods: The effects of CUMS exposure were assessed by measuring oxidative stress markers, antioxidant activity, and neuronal damage in the hippocampus using histopathology, network pharmacology, Western blot analysis, and small interfering RNA (siRNA) knockdown experiments. Results: 1,8-CH significantly alleviated depression-like behaviors in CUMS mice. CUMS exposure induced oxidative stress in the hippocampus, evidenced by elevated MDA levels, decreased antioxidant activity, and neuronal damage. DHE staining revealed ROS accumulation. Treatment with 1,8-CH alleviated oxidative stress by reducing MDA, restoring antioxidant activity, and lowering ROS levels, while improving neuronal structure. Network pharmacology identified the PI3K/Akt/Nrf2 pathway as a key mediator of 1,8-CH’s neuroprotection, which was supported by Western blot results, demonstrating PI3K/Akt activation and a potential enhancement of Nrf2 nuclear translocation. Furthermore, in corticosterone-induced PC12 cells, the antioxidant effects of 1,8-CH were abolished by Nrf2 inhibition and siRNA knockdown, confirming Nrf2’s role. Conclusions: These findings suggest that 1,8-CH alleviates hippocampal oxidative stress in CUMS-induced depression via the PI3K/Akt/Nrf2 pathway, highlighting its potential as a health supplement for managing depression. Full article