Chronic Mild Stress Research Articles

Effect of vortioxetine and fluoxetine on immunohistochemical expression of Caspase-8, RANKL, and IL-6 in testicular tissue in an experimental depression model.

The main symptoms of depression, a chronic mental illness, include sadness, low self-esteem, and a diminished sense of enjoyment in life. Many factors have been suggested to be associated with depression, one of which is low testosterone in men. The serotonin reuptake inhibitor fluoxetine (FLU), used to treat depression, has been reported to potentially have detrimental effects on spermatogenesis in rats after long-term use. The multimodal antidepressant vortioxetine (VTX) offers new promise for the treatment of depression. The chronic unpredictable mild stress (CUMS) model is widely known as an experimental paradigm used to study depression-like behaviors in rodents. Stress leads to various neurochemical and immune changes, affecting multiple organs. Our study aims to examine the histopathological findings in testicular tissue induced by CUMS and the immunohistochemical expression of Cas-8, IL-6, and RANKL using a depression model in rats. Rats were split into 4 groups of 7 animals each at random. Group 1 (control) did not experience any stress. Group 2 (CUMS) was exposed to chronic, unpredictable mild stress using a specific procedure. Group 3 (CUMS+VTX) and Group 4 (CUMS+FLU) underwent CUMS and received intraperitoneal drug treatment at a dose of 10 mg/kg during the final three weeks of the study. The rat testicles collected during necropsy were evaluated histopathologically and immunohistochemically for Cas-8, IL-6, and RANKL expressions using a light microscope. In Group 1, histological analysis showed normal tissue architecture in the testicles and epididymis. In Group 2, there was significant depletion of spermatozoa in the seminiferous tubules and empty tubules in the epididymis. In Groups 3 and 4, FLU and VTX treatment led to improvements in the testicles. Cas-8, RANKL, and IL-6 immunohistochemistry revealed increased expression in Group 2, primarily in interstitial cells. In Groups 1, 3, and 4, no or very slight expression of these markers was observed. The results of this study showed that sperm production in the testes is negatively affected in CUMS-induced depression and that Cas-8, IL-6, and RANKL expression is increased, particularly in interstitial cells. VTX and FLU, used in the treatment of depression, suggest potential for mitigating the adverse effects of CUMS on the testes.

Limosilactobacillus reuteri fermented brown rice alleviates anxiety improves cognition and modulates gut microbiota in stressed mice

Chronic stress disrupts gut microbiota homeostasis, contributing to anxiety and depression. This study explored the effects of Limosilactobacillus reuteri fermented brown rice (FBR) on anxiety using an ICR mouse chronic mild stress (CMS) model. Anxiety was assessed through body weight, corticosterone levels, neurotransmitter profiles, and behavioral tests. A four-week FBR regimen reduced corticosterone, restored neurotransmitters like gamma-aminobutyric acid (GABA) and serotonin, and improved anxiety-related behaviors. Metagenomic (16S rRNA) and metabolomic analyses revealed enhanced amino acid metabolism, energy metabolism, and short-chain fatty acid (SCFA) production in FBR-treated mice. FBR-enriched beneficial gut bacteria, aligning the microbiota profile with that of non-stressed mice. FBR also modulated GABA receptor-related gene expression, promoting relaxation. Network pharmacology identified quercetin, GABA, glutamic acid, phenylalanine, and ferulic acid as bioactive compounds with neuroprotective potential. These findings highlight FBR’s potential as a gut-brain axis-targeted therapeutic for anxiety and stress-related disorders.

Subacute Symptoms of Depression and Anxiety in Stress-Exposed Mice: Role of Schinus terebinthifolia Raddi Leaf Lectin (SteLL).

Anxiety and depression are leading causes of disability worldwide, often exacerbated by chronic stress. Schinus terebinthifolia Raddi. has been used in traditional medicine for several purposes. Among these, the use of bark-and-leaf tea and leaf decoction to treat depression has been reported. Previous studies showed that the S. terebinthifolia leaf lectin (SteLL) can ameliorate anxiety and depression symptoms in mice. To investigate SteLL as a compound from S. terebinthifolia leaf able to alleviate symptoms of depression and anxiety in an unpredictable chronic mild stress (UCMS) animal model. Mice were subjected to four-week UCMS and then treated with SteLL at 2 and 4 mg/kg (i.p.) or with fluoxetine at 10 mg/kg i.p. (positive control) for 21 days. Behavioral assessments were conducted using the open field test, elevated plus maze, tail suspension test, and sucrose preference test. Serum corticosterone and inflammatory markers (cytokines) levels were determined. The levels of cytokine, oxidative stress indicators and monoamines in brain homogenates were also measured to understand the biochemical changes induced by SteLL treatment. SteLL treatment at both doses significantly (p < 0.05) alleviated the stress-induced behavior in mice, reducing the anxiety and depression signals in all tests. SteLL administration increased the brain levels of monoamines noradrenaline and serotonin in comparison with UCMS control mice that received only vehicle. SteLL reduced superoxide production, lipid peroxidation and improved reduced glutathione (GSH) levels in the brain. The lectin also increased serum and brain levels of anti-inflammatory cytokine IL-4, while reducing levels of pro-inflammatory cytokines. Serum corticosterone levels were not decreased by lectin treatment. Our findings highlight SteLL as a neuromodulatory agent from S. terebinthifolia leaves effective in subacute and stress-induced anxiety and depression through modulation of monoaminergic, oxidative stress, and inflammatory pathways. The data shows the potential of this lectin as a therapeutic agent for stress-related neuropsychological disorders.

MicroRNA-204-5p Deficiency within the vmPFC Region Contributes to Neuroinflammation and Behavioral Disorders via the JAK2/STAT3 Signaling Pathway in Rats.

Major depressive disorder (MDD) is usually considered associate with immune inflammation and synaptic injury within specific brain regions. However, the molecular mechanisms underlying the neural deterioration resulting in depression remain unclear. Here, it is found that miR-204-5p is markedly downregulated in the ventromedial prefrontal cortex (vmPFC) in a chronic unpredictable mild stress (CUMS) induce rat model of depression. Knockdown of miR-204-5p in the vmPFC of normal rats results in depression and anxiety-like behaviors accompanied with the activation of microglia, elevated levels of pro-inflammatory cytokines, and increased numbers of neural apoptotic cells, effects which appear to be mediated by activation of the JAK2/STAT3 signaling pathway. Electrophysiological recordings further demonstrate that knockdown of miR-204-5p induces abnormal excitability of pyramidal neurons. In contrast, upregulation of miR-204-5p in the vmPFC of CUMS rats significantly causes inhibition of JAK2/STAT3 signaling pathway, improvements in neuronal impairments, and an abolition of the depression and anxiety-like behaviors. Moreover, pharmacological blocking of the JAK2/STAT3 signaling pathway significantly ameliorates abnormal behaviors resulting from miR-204-5p deficiency within the vmPFC. Collectively, these results provide robust evidence that the miR-204-5p/JAK2/STAT3 pathway may critically involve in the pathogenesis of depression, which may serve as potentially critical therapeutic target in the treatment of MDD.

Cannabidiol Modulates Neuroinflammatory and Estrogen-Related Pathways in a Sex-Specific Manner in a Chronic Stress Model of Depression

Evidence indicates a bidirectional link between depressive symptoms and neuroinflammation. This study evaluated chronic cannabidiol (CBD) treatment effects in male and female rats subjected to the unpredictable chronic mild stress (UCMS) model of depression. We analyzed the gene expression related to neuroinflammation, cannabinoid signaling, estrogen receptors, and specific microRNAs in the ventromedial prefrontal cortex (vmPFC), CA1, and ventral subiculum (VS). UCMS influenced immobility in a sex-specific manner, increasing it in males and decreasing it in females, effects that were reversed by CBD. CBD also normalized the UCMS-induced upregulation of tumor necrosis factor α (TNF-α) in the CA1 and VS in males. In both sexes, UCMS induced the upregulation of the nuclear factor kappa B subunit 1 (NF-κB1) gene in the VS, which was unaffected by CBD. Additionally, CBD reversed CB1 downregulation in the VS of males but not in the vmPFC of either sex. In males, CBD restored the UCMS-induced downregulation of VS estrogen receptor genes ERα and ERβ. UCMS also altered miR-146a-5p expression, downregulating it in females (VS) and upregulating it in males (CA1), with no CBD effect. These findings highlight the sex-specific mechanisms of CBD’s antidepressant effect, with hippocampal neuroinflammatory and estrogenic pathways playing a key role in males.

Psychological stress disturbs bone metabolism via miR-335-3p/Fos signaling in osteoclast.

It has been well validated that chronic psychological stress leads to bone loss, but the underlying mechanism remains unclarified. In this study, we established and analyzed the chronic unpredictable mild stress (CUMS) mice to investigate the miRNA-related pathogenic mechanism involved in psychological stress-induced osteoporosis. Our result found that these CUMS mice exhibited osteoporosis phenotype that is mainly attributed to the abnormal activities of osteoclasts. Subsequently, miRNA sequencing and other analysis showed that miR-335-3p, which is normally highly expressed in the brain, was significantly downregulated in the nucleus ambiguous, serum, and bone of the CUMS mice. Additionally, in vitro studies detected that miR-335-3p is important for osteoclast differentiation, with its direct targeting site in Fos. Further studies demonstrated FOS was upregulated in CUMS osteoclast, and the inhibition of FOS suppressed the accelerated osteoclastic differentiation, as well as the expression of osteoclastic genes, such as Nfatc1, Acp5, and Mmp9, in miR-335-3p-restrained osteoclasts. In conclusion, this work indicated that psychological stress may downregulate the miR-335-3p expression, which resulted in the accumulation of FOS and the upregulation of NFACT1 signaling pathway in osteoclasts, leading to its accelerated differentiation and abnormal activity. These results decipher a previously unrecognized paradigm that miRNA can act as a link between psychological stress and bone metabolism.

Investigating the role of GPR39 in treatment of stress-induced depression and anxiety.

Chronic stress is one of the leading causes of depression. Yet, knowledge of the pathomechanism of this process still eludes us. Chronic unpredictable mild stress (CUMS) model of depression enables researchers to look for a root cause of the disease in mice by mimicking a stressful human environment. Since zinc has already been shown to impact the treatment of depression, in our study we aimed to shed light on the role of the zinc receptor GPR39 in stress-induced depression. We also aimed to highlight the role of GPR39 activation in monoamine-based antidepressant treatment. Using large battery of behavioural tests, we provided a detailed description of CUMS-induced phenotype in both - CD-1 and GPR39 knock-out mice. Our experiments showed that combined treatment with TC-G 1008 (GPR39 agonist) and antidepressants produces stronger antidepressant-like effect of classic antidepressants. We also demonstrated the inter-strain differences in stress response and the greater stress susceptibility of GPR39 knock-out mice. The lack of GPR39 expression also either diminished or completely abolished the response to treatment with different antidepressants combined with TC-G 1008. The results show that GPR39 KO mice are more susceptible to chronic stress and that they are non-responsive to SSRI treatment. Utilizing various behavioural tests gave us much broader understanding not only of the role of GPR39 in depression treatment, but also of the importance of detailed behavioural description in a proper interpretation of the results. Further research with known selective agonists and antagonists of GPR39 will be necessary to understand the full potential of this receptor as a pharmacological target.

Cichorium intybus L. Oligo-Polysaccharides (CIO) Exerts Antianxiety and Antidepressant Effects on Mice Experiencing Behavioral Despair and Chronic Unpredicted Mild Stress.

Cichorium intybus L. oligo-polysaccharides (CIOs), obtained from Cichorium intybus L., is a mixture of oligosaccharides and polysaccharides. This study explores the antianxiety and antidepressant effects and mechanisms of CIOs by using acute behavioral despair and chronic unpredictable mild stress mice models and measuring the levels of 5-HT and the expression of proteins related to the BDNF/ERK and PI3K/Akt/mTOR pathways. Moreover, 56 male C57BL/6N mice were used to test behavioral despair. They were randomized into seven groups (Control, Citalopram, CIO 12.5 mg/kg, CIO 25 mg/kg, CIO 100 mg/kg, and CIO 200 mg/kg) based on body weight; they were administered with the corresponding medication daily for 7 days; and behavioral tests were conducted on them (forced swimming test (FST) and tail suspension test (TST)) after 7 days. Seventy male C57BL/6N mice were adopted in the next part of the experiment and randomly divided into seven groups (Control, CUMS, Fluoxetine, MOO, CIO 25 mg/kg, and CIO 100 mg/kg) based on the sucrose preference index. Except for the control group, the other groups were subjected to 6 weeks of CUMS. From the fifth week of stress, the corresponding drugs were administered by gavage until the end of the behavioral tests. In the behavioral despair tests, the immobility time was significantly reduced in the FST and TST after the CIO (25 and 100 mg/kg) treatment of 7 days. After 6 weeks of chronic unpredicted mild stress (CUMS) treatment, CIO (25, 50, and 100 mg/kg) administration significantly reduced the number of buried beads in the marble burying test (MBT), decreased the latency in the novelty-suppressed feeding test (NSFT), and shortened the immobility time in the FST and TST. CIO administration significantly increased the sucrose preference index in the sucrose preference test (SPT). Additionally, CIO treatment increased hippocampal 5-HT levels while upregulating the expression of BDNF, P-PI3K/PI3K, P-ERK/ERK, P-Akt/Akt, and P-mTOR/mTOR. In summary, CIO exerted promising antidepressant effects in behavioral despair and antianxiety and antidepressant effects in CUMS-induced depressive mice. Moreover, CIO therapy was facilitated by increasing the 5-HT content, alleviating the damage of hippocampal neurons, and upregulating the BDNF/ERK and PI3K/AKT/mTOR cascade. Thus, CIO is a substance with the potential to treat anxiety and depression.

Ashwagandha (Withania somnifera (L.) dunal) root extract containing withanolide a alleviates depression-like behavior in mice by enhancing the brain-derived neurotrophic factor pathway under unexpected chronic mild stress.

Ashwagandha (Withania somnifera (L.) Dunal) root or whole-plant extracts are used to treat anxiety, insomnia, and other nervous system disturbances. We evaluated the neuroprotective and antidepressant effects of ashwagandha root extract (ARE) on corticosterone-exposed HT-22cells and unpredictable chronic mild stress (UCMS)-challenged mice. The neuroprotective properties of ARE containing withanolide A were assessed in HT-22cells subjected to corticosterone-induced oxidative stress. Additionally, the effects of ARE on depression-like behavior, stress-related hormones, and inflammatory cytokine levels were evaluated in a mouse model of UCMS. In HT-22cells, ARE (100 and 200μg/mL) and its constituent, withanolide A (1.56 and 3.12μg/mL), mitigated corticosterone-induced increases in MAO activity, ROS, and MDA levels. Treatment also reversed corticosterone-induced reductions in BDNF, TrkB, p-AKT, p-ERK, and p-CREB and normalized Nrf2 and Keap1 levels, thereby elevating HO-1 expression. In UCMS mice, ARE improved behavioral outcomes, increased sucrose preference, and reduced immobility in the forced swimming test while enhancing activity in the open field test and elevated plus maze. ARE decreased the levels of stress hormones (corticotropin-releasing hormone, adrenocorticotropic hormone, and corticosterone) and increased the levels of neurotransmitters (L-DOPA, 5-HTP, and serotonin). Histological analysis revealed that ARE reduced hippocampal cell loss. Additionally, ARE (60 and 100mg/kg) restored decreased levels of p-AKT, p-ERK, and p-CREB and lowered inflammation-related proteins (Cox2, iNOS, IL-6, IL-1β, TNF-α). These results indicate that ARE containing withanolide A exhibits notable neuroprotective and antidepressant properties.

Acrylamide Exposure Promotes the Progression of Depression-like Behavior in Mice with CUMS via GSDMD-Mediated Pyroptosis

AIMWe investigated the mechanism by which the environmental toxin acrylamide (AM) promotes depression. MethodsA depression mouse model was constructed using the chronic unpredictable mild stress method, AM was administered orally to simulate the exposure state. Depressive-like behavioral changes were assessed by open field test, elevated plus maze test, swimming test, and sucrose preference test. Enzyme-linked immunosorbent assay (ELISA) was used to detect tissue inflammatory factor levels, hematoxylin and eosin (H&E) and Nissl staining to detect neuronal damage, immunohistochemical staining to detect IBA-1 expression, and Western-blotting to detect protein levels. GSDMD knockout (KO) mice and the GSDMD inhibitor LDC7559 were used to inhibit GSDMD. In vitro, primary microglia were used, and AM intervention was applied to detect the levels of cellular inflammatory factors, and fluorescence staining was used to detect GSDMD-NT, and propidium iodide (PI) was used to detect the level of pyroptosis. ResultsAM can exacerbate CUMS-like depression in mice, increase the levels of inflammatory factors in brain tissue, and worsen neuronal damage, with upregulation of IBA-1 expression, and can increase the expression of NLRP3, GSDMD, and GSDMD-NT. When GSDMD-KO or LDC7559 intervention was applied, it could antagonize the effects of AM and improve CUMS-like depression. In microglial cell experiments, AM could promote pyroptosis in microglial cells, increase the expression of inflammatory factors, and when GSDMD-KO was applied, it could inhibit the effects of AM. ConclusionAM can promote the progression of depression in CUMS-like mice via GSDMD-mediated pyroptosis, while also increasing tissue inflammatory levels. GSDMD is an important target for the neurotoxicity of AM.

Paroxetine alleviates ulcerative colitis in mice via restoring intestinal microbiota homeostasis and metabolism.

Ulcerative colitis (UC) is an inflammatory bowel disease and psychological factors may be one of its pathogeneses. Selective serotonin reuptake inhibitor drug such as paroxetine with an effective anti-depression ability may be a new option for UC treatment. To evaluate the therapeutic effect of paroxetine on the exacerbation of UC symptoms caused by depression, a dual model of C57BL/6 mice was established using dextran sulphate sodium and chronic unpredictable mild stress (CUMS). Behavioural experiments, H&E staining and the level of 5-hydroxytryptamine (5-HT) in the brain were used to demonstrate successful replication of the CUMS model. The levels of 5-HT, TNF-α and IL-1β in the colon and the activity of MPO in the serum were determined by ELISA kits. The levels of some gut microbiota in the faeces were measured by qPCR and faecal differential metabolites were analysed by 1H NMR. The results indicate that CUMS can exacerbate UC symptoms in mice by exacerbating inflammation, and UC+CUMS can disrupt gut microbiota and fatty acid metabolism. Paroxetine can improve the mental state of mice, reduce serum MPO activity, but increase TNF-α and IL-1β levels in the colon. In addition, paroxetine also can restore the intestinal flora of mice and improve intestinal absorption and metabolic function of amino acids and short-chain fatty acids.

Cordycepin Extracted from Cordyceps militaris mitigated CUMS-induced depression of rats via targeting GSK3β/β-catenin signaling pathway.

Cordycepin, the main active component of Cordyceps militaris, exhibits various pharmacological activities, including anti-tumor and antioxidant effects. However, its antidepressant effect and the underlying mechanisms remain unclear. This study aimed to explore the antidepressant effect of cordycepin and elucidate the potential molecular mechanisms. Chronic unpredictable mild stress (CUMS) rat model was established to assess antidepressant effect of cordycepin. Gas chromatography-mass spectrometry (GC-MS) metabolomics with integrated network pharmacology were used to find differential metabolites in serum, brain, and cerebrospinal fluid of rats and identify potential target by cordycepin. Western blot and Real-time PCR were applied to validate the signaling pathway. Cordycepin alleviated CUMS-induced depression-like behaviors by weight gain, sucrose preference increment, immobility time reduction, total travelling distance extension and serum corticosterone levels reduction. Metabolomics showed that cordycepin reversed CUMS-induced metabolic disturbances through alanine and TCA cycle metabolism pathways. Network pharmacology identified GSK3β as a potential target. Cordycepin increased protein levels of p-GSK3β, β-catenin and nuclear β-catenin, and enhanced transcription of downstream genes PKM, LDHA, Cyclin D1 and C-myc in brains of CUMS-induced rats. This study indicated that cordycepin exerted antidepressant effect by modulating GSK3β/β-catenin pathway, suggesting its potential as a candidate agent for depression.

Hydrogen restores central tryptophan and metabolite levels and maintains mitochondrial homeostasis to protect rats from chronic mild unpredictable stress damage.

The field of hydrogen medicine has garnered extensive attention since Professor Ohsawa established that low concentrations of hydrogen (2%-4%) exert antioxidant effects. The present study aimed to evaluate the therapeutic effect of molecular hydrogen in a CUMS rat model. A total of 40 SD rats were randomly divided into a control group, a model group, a hydrogen group, and a positive drug group. Four weeks post-modeling, hydrogen inhalation and other treatments were administered. Behavioral, biochemical, and immunohistochemical evaluations were performed after treatment. Hydrogen inhalation alleviated depressive behavior and hippocampal neuronal damage in CUMS rats, as well as restored the levels of neurotransmitters, inflammatory factors, and oxidative stress. Moreover, it maintained mitochondrial homeostasis and up-regulated the expression of PGC-1α, PINK1, and Parkin. The results collectively indicated that hydrogen significantly attenuated CUMS-induced depressive-like behavior and monoamine neurotransmitter deficiency, as well as protected the brain from oxidative stress and inflammatory damage and effectively preserved mitochondrial homeostasis.

The molecular mechanism of Xiaoyaosan in treating major depressive disorder: Integrated analysis of DNA methylation and RNA sequencing of the arcuate nucleus in rats.

Xiaoyaosan, a classic Chinese herbal formula, exhibits promising antidepressant effects. However, its specific antidepressant mechanisms remain incompletely understood. Previous studies have highlighted the significant role of DNA methylation in the pathogenesis of major depressive disorder (MDD). Yet, whether the effects of Xiaoyaosan are linked to DNA methylation and its regulation remains unclear. This study aims to explore and verify the molecular mechanism of Xiaoyaosan in treating MDD via integrated analysis of DNA methylation and RNA sequencing. In this study, a chronic unpredictable mild stress (CUMS) model was established to induce MDD in rats, which were subsequently orally treated with Xiaoyaosan, with fluoxetine as a positive control. Antidepressant effects were assessed by the open field test, sucrose preference test, and forced swimming test. Whole-genome bisulfite sequencing (WGBS) and bulk RNA sequencing were performed in the arcuate nucleus of hypothalamus to assess methylation changes and identify differentially expressed genes. Bioinformatics analyses were conducted to explore methylation alterations, RNA sequencing profiles, and their shared epigenetic as well as gene expression changes, to identify candidate genes. Finally, RT-PCR was used to validate the key differential genes. Xiaoyaosan effectively reversed depressive-like behaviors. Further, Xiaoyaosan treatment involved multiple epigenetic modifications. The results of differentially methylated genes showed that there were 1353 overlapped genes between M-vs-C-hypo gene and X-vs-M-hyper gene, 5326 overlapped genes between M-vs-C-hyper gene and X-vs-M-hypo gene. GO and KEGG enrichment analyses indicated these intersecting genes were involved in biological regulation, transcription factors, appetite and endocrine control systems, etc. The analysis of differentially expressed genes from RNA sequencing revealed that there were 25 overlapping genes between the M vs C hypomethylated group and the X vs M hypermethylated group, while 81 overlapping genes were identified between the M vs C hypermethylated group and the X vs M hypomethylated group. Those differential genes regulated by methylation enriched in processes related to brain and neuronal growth, neuropeptide and hormone activation, as well as biological processes and molecular functions associated with protein translation, synthesis, transport, and localization. The integrated analysis of DNA methylation and RNA sequencing screened 14 potentially differential genes, which were associated with appetite regulation, energy metabolism, and neuroreceptor ligands. PCR verification found that Lmx1b, Abcc5, Gpc3 and Cfb showed statistical differences. The antidepressant mechanism of Xiaoyaosan involves the biological regulation in the arcuate nucleus of hypothalamus, including transcription factors, neurotransmitter regulation, neural development, appetite regulation peptides, and endocrine control systems. The methylation level and regulation at the gene locus of Lmx1b, Abcc5, Gpc3, and Cfb may play a key role in the treatment of Xiaoyaosan. These findings provide new insights into the therapeutic mechanisms of Xiaoyaosan.

Ansofaxine suppressed NSCLC progression by increasing sensitization to combination immunotherapy.

Depression negatively impacts the prognosis of various cancers, including lung cancer, by influencing antitumor immune responses and impairing immune cell function. Antidepressants may modulate the tumor immune microenvironment, enhancing immunotherapy efficacy. However, the specific mechanisms remain unclear. This study investigates the effects of the antidepressant Ansofaxine on immune therapy in non-small cell lung cancer (NSCLC) mice with comorbid depression. Chronic unpredictable mild stress (CUMS) and Lewis lung cancer cells (LLC) model was established in mice. Ansofaxine and a combination of triple immunotherapy (anti-PD-1, anti-TNFR2, and anti-PTP1B) were treated in mice to monitor tumor growth and survival rates. Flow cytometry and immunohistochemistry were employed to analyze the dynamics of the immune system, while ELISA kits were used to quantify neurotransmitter levels. Depression accelerated NSCLC progression, evidenced by increased tumor volume, spleen size, and reduced survival rates. Flow cytometry analysis demonstrated a reduction in the population of immune effector cells, with an increase in the proportion of immunosuppressive cells. Ansofaxine inhibited LLC cell proliferation and migration, enhancing apoptosis more effectively than venlafaxine and fluoxetine. Combined with triple immunotherapy, Ansofaxine improved survival rates and enhanced immune responses, increasing CD8+ T cell proportions and decreasing Tregs. Ansofaxine also restored serum serotonin and norepinephrine levels in depressed mice, reduced corticosterone, and decreased PD-L1 and TNFR2 expression in tumor tissues. The findings suggest that Ansofaxine may represent a promising therapeutic approach for NSCLC patients with comorbid depression, potentially enhancing both mental well-being and cancer-related outcomes.

Resveratrol alleviates depression-like behaviors by inhibiting ferroptosis via AKT/NRF2 pathway.

Major depressive disorder (MDD) is common, and successful treatment remains challenging. Resveratrol, a naturally occurring polyphenol, has been shown to alleviate depression-like behaviors, but the underlying mechanisms remain unclear. We previously developed a new model of depression by inducing hippocampal ferroptosis in rats, suggesting that ferroptosis may be involved in the development of MDD. Here, we further explored the antidepressant-like effect of resveratrol and its association with ferroptosis. Male rats were exposed to chronic unpredictable mild stress (CUMS), with or without resveratrol, followed by comprehensive behavioral testing. In PC12 cells in vitro, LY294002 (an AKT inhibitor) and ML385 (an NRF2 inhibitor) were used to elucidate the involvement of AKT/NRF2 signaling in resveratrol-mediated ferroptosis. mRNA and protein levels of AKT/NRF2 pathway and ferroptosis-related targets were measured. Ferroptosis was quantified by measuring malondialdehyde (MDA), glutathione (GSH), and Fe2+ content and superoxide dismutase (SOD) activity. Resveratrol ameliorated depression-like behaviors in rats, simultaneously restoring AKT/NRF2 pathway and ferroptosis-related targets in the hippocampus downregulated by CUMS. Elevated markers of oxidative stress in plasma were attenuated by resveratrol. Furthermore, erastin induced ferroptosis and inhibited AKT/NRF2 signaling in PC12 cells, which was counteracted by resveratrol. Additionally, the impact of resveratrol on erastin-induced ferroptosis was reversed by LY294002 and ML385. This study demonstrates that resveratrol ameliorates depression-like behaviors by inhibiting ferroptosis via the AKT/NRF2 pathway.

Pink1/Parkin signaling mediates pineal mitochondrial autophagy dysfunction and its biological role in a comorbid rat model of depression and insomnia

Using a chronic unpredictable mild stress (CUMS) combined with multi-platform water environment sleep deprivation (SD) as an animal model, the occurrence and development of human depression combined with insomnia were simulated. The abnormal mitochondrial autophagy signaling caused by the putative kinase 1/Parkin E3 ubiquitin protein ligase (Pink1/Parkin) signaling pathway directly affects the normal secretion of melatonin by the pineal gland, which may explain the pathogenesis of depression combined with insomnia. This study aims to explore the depression-like behavior, sleep changes, central oxidative stress response, pineal mitochondrial autophagy damage, melatonin secretion, histopathological changes of the pineal gland, and the expression of Pink1/Parkin signaling-related factors in CUMS+SD rats. The results showed that the levels of reactive oxygen species (ROS) in cerebrospinal fluid of CUMS+SD rats significantly increased along with the inflammatory factors Interleukin-1β (IL-1β) and nuclear factor kappa-B (NF-κB) in cerebrospinal fluid. In addition, the number of pineal gland cells significantly decreased, cell boundaries became blurred, cell volume shrank, and apoptotic bodies appeared in the pineal gland tissue under HE staining, indicating pineal gland inflammation. Sleep deprivation further disrupted the levels of autophagy damage factors, including histamine (MDA), glutathione (GSH), and catalase (CAT), in the cerebrospinal fluid of CUMS + SD rats. Transmission electron microscopy of the pineal gland in CUMS+SD rats revealed damage to mitochondrial autophagy. The levels of 5-hydroxytryptamine (5-HT) and aromatic amine-N-acetyltransferase (AANAT) in the cerebrospinal fluid, as well as melatonin levels in the pineal gland, were significantly decreased. Additionally, the expression of IL-1β, NF-κB, Pink1, and Parkin in the pineal gland of CUMS+SD rats significantly increased. The expression of microtubule-associated protein 1 light chain 3-β (LC3), selective autophagy adaptor protein (P62), cytochrome c oxidase IV (COXIV), and mitochondrial outer membrane translocation enzyme 20 (TOM20) proteins downstream of the Pink1/Parkin signaling pathway was enhanced, while the expression of downstream brain-derived neurotrophic factor (BDNF), Beclin 1, and BCL2 interacting protein 3 (BNIP3) proteins was negatively regulated. Pink1/Parkin signaling may specifically respond to mitochondrial autophagy damage in the pineal gland, affecting the normal synthesis and secretion of melatonin in the pineal gland. In summary, mitochondrial autophagy damage in the pineal gland affects the normal secretion of melatonin in CUMS+SD rats, which is closely related to the specific autophagy signaling impairment of Pink1/Parkin pathway, which may mediate the occurrence of depression combined with insomnia.

Glucocorticoid-Dependent Retinal Degeneration and Vision Impairment in Mice Susceptible to Prenatal Stress-Induced Behavioral Abnormalities.

Chronic exposure to prenatal stress can impair neurogenesis and lead to irreversible cognitive and neuropsychiatric abnormalities in offspring. The retina is part of the nervous system; however, the impacts of prenatal stress on retinal neurogenesis and visual function remain unclear. This study examined how elevated prenatal glucocorticoid levels differentially affect retinal development in the offspring of pregnant mice exposed to chronic unpredictable mild stress (CUMS). Offspring were classified into control, stress-resilient, and stress-susceptible groups based on behavioral tests assessing spatial memory and depression-like behaviors. The stress-susceptible group exhibited significantly altered synaptogenesis, reduced ganglion cell development, decreased retinal thickness, and visiual impairment. These mice also showed a pervasive transformation of retinal astrocytes into a proinflammatory A1-like reactive state, evidenced by increased GFAP and decreased STAT3 expression levels. This astrocyte phenotype shift coincided with disruptions in neurogenesis and synaptic formation. Furthermore, prenatal exposure to exogenous corticosterone confirmed that the effects of prenatal stress are mediated by glucocorticoid-induced retinal neurodegeneration. Our findings suggest that elevated prenatal glucocorticoid levels trigger a series of neurodevelopmental disturbances leading to retinal neurodegeneration and vision impairment. This research highlights the impact of prenatal stress on retinal development and visual health, suggesting new avenues for understanding and potentially mitigating the negative effects of early-life stress on neurodevelopment.

Microglia‐Derived Vitamin D Binding Protein Mediates Synaptic Damage and Induces Depression by Binding to the Neuronal Receptor Megalin

AbstractVitamin D binding protein (VDBP) is a potential biomarker of major depressive disorder (MDD). This study demonstrates for the first time that VDBP is highly expressed in core emotion‐related brain regions of mice susceptible to chronic unpredictable mild stress (CUMS). Specifically, the overexpression of microglia (MG)‐derived VDBP in the prelimbic leads to depression‐like behavior and aggravates CUMS‐induced depressive phenotypes in mice, whereas conditional knockout of MG‐derived VDBP can reverse both neuronal damage and depression‐like behaviors. Mechanistically, the binding of MG‐derived VDBP with the neuronal receptor megalin mediates the downstream SRC signaling pathway, leading to neuronal and synaptic damage and depression‐like behaviors. These events may be caused by biased activation of inhibitory neurons and excitatory–inhibitory imbalance. Importantly, this study has effectively identified MG‐derived VDBP as a pivotal mediator in the interplay between microglia and neurons via its interaction with the neuronal receptor megalin and intricate downstream impacts on neuronal functions, thus offering a promising therapeutic target for MDD.

Predicting Future Development of Stress-Induced Anhedonia From Cortical Dynamics and Facial Expression.

The current state of mental health treatment for individuals diagnosed with major depressive disorder leaves billions of individuals with first-line therapies that are ineffective or burdened with undesirable side effects. One major obstacle is that distinct pathologies may currently be diagnosed as the same disease and prescribed the same treatments. The key to developing antidepressants with ubiquitous efficacy is to first identify a strategy to differentiate between heterogeneous conditions. Major depression is characterized by hallmark features such as anhedonia and a loss of motivation1,2, and it has been recognized that even among inbred mice raised under identical housing conditions, we observe heterogeneity in their susceptibility and resilience to stress3. Anhedonia, a condition identified in multiple neuropsychiatric disorders, is described as the inability to experience pleasure and is linked to anomalous medial prefrontal cortex (mPFC) activity4. The mPFC is responsible for higher order functions5-8, such as valence encoding; however, it remains unknown how mPFC valence-specific neuronal population activity is affected during anhedonic conditions. To test this, we implemented the unpredictable chronic mild stress (CMS) protocol9-11 in mice and examined hedonic behaviors following stress and ketamine treatment. We used unsupervised clustering to delineate individual variability in hedonic behavior in response to stress. We then performed in vivo 2-photon calcium imaging to longitudinally track mPFC valence-specific neuronal population dynamics during a Pavlovian discrimination task. Chronic mild stress mice exhibited a blunted effect in the ratio of mPFC neural population responses to rewards relative to punishments after stress that rebounds following ketamine treatment. Also, a linear classifier revealed that we can decode susceptibility to chronic mild stress based on mPFC valence-encoding properties prior to stress-exposure and behavioral expression of susceptibility. Lastly, we utilized markerless pose tracking computer vision tools to predict whether a mouse would become resilient or susceptible based on facial expressions during a Pavlovian discrimination task. These results indicate that mPFC valence encoding properties and behavior are predictive of anhedonic states. Altogether, these experiments point to the need for increased granularity in the measurement of both behavior and neural activity, as these factors can predict the predisposition to stress-induced anhedonia.