Inflammation in Depression and the Potential for Anti-Inflammatory Treatment

Microglial-Biomimetic Memantine-Loaded Polydopamine Nanomedicines for Alleviating Depression

Depression is a common psychiatric disorder, and monoamine-based antidepressants as first-line therapy remain ineffective in some patients. The synergistic modulation of neuroinflammation and neuroplasticity could be a major strategy for treating depression. In this study, an inflammation-targeted microglial biomimetic system, PDA-Mem@M, is reported for treating depression. Microglial membrane-coated nanoparticles penetrate the blood-brain barrier and facilitate microglial targeting. Subsequently, owing to the excellent free radical-scavenging capacity, PDA-Mem@M attenuate the brain inflammatory microenvironment. After on-demand release from the nanoparticles, memantine increases the expression of brain-derived neurotrophic factors and reverses the loss of synaptic dendritic spines. Further, in vivo studies demonstrate that PDA-Mem@M effectively alleviate depression-like behaviors to a greater extent than memantine or polydopamine nanoparticles (PDA) monotherapy. This synergistic strategy, with satisfactory biosafety and strong anti-inflammatory and synaptic plasticity restoration effects, is conducive to advances in depression therapy.

Examining systemic inflammation as a pathway linking peer victimization to depressive symptoms in adolescence

BACKGROUND

Adolescents exposed to victimization are at an increased risk for a variety of adverse mental health outcomes, including depressive symptoms. Yet, the biological pathways underlying these associations remain poorly understood. Focusing on within-person processes, we examined whether low-grade systemic inflammation mediated the longitudinal associations between peer victimization and depressive symptoms in adolescence.

METHODS

207 adolescents (at baseline Mage = 12.69 years; SD = 0.49; 43.5% female) participated in a multi-wave longitudinal study, with assessments repeated every 6 months over 1.5 years. At each assessment wave, participants self-reported their peer victimization experiences and depressive symptoms. Dried blood spots were collected at each wave using a finger prick procedure to assay a key marker of low-grade systemic inflammation, interkeukin-6 (IL-6). Data were analyzed using random-intercept cross-lagged panel models.

RESULTS

The cross-lagged paths from IL-6 to depressive symptoms were significant across all models and waves (β12 = .13; β23 = .12; β34 = .08), indicating that when adolescents' levels of low-grade systemic inflammation were above their person-specific average, they reported increased levels of depressive symptoms in the subsequent months. However, no significant cross-lagged within-person associations emerged between peer victimization and either IL-6 or depressive symptoms.

CONCLUSIONS

The findings provide no evidence for the hypothesized mediating role of inflammation in the within-person associations between peer victimization and depressive symptoms. Nevertheless, they extend prior research by indicating that elevated levels of low-grade systemic inflammation predict the development of depressive symptoms in adolescence.

Transcutaneous Auricular Vagus Stimulation Attenuates LPS-Induced Depression-Like Behavior by Regulating Central α7nAChR/JAK2 Signaling

Depression is a serious disabling disease worldwide. Accumulating evidence supports that there is a close relationship between depression and inflammation, and then inhibition of neuroinflammation may be another mechanism for the treatment of depression. Transcutaneous auricular vagus stimulation (taVNS), as a noninvasive transcutaneous electrical stimulation, could effectively treat depression, but its mechanism is unclear. In this study, rats with depression-like behavior were induced by intraperitoneal injection of lipopolysaccharide (LPS). The rats were randomly divided to control group, LPS group, taVNS + LPS group, and the same as the α7 nicotinic acetylcholine chloride receptor (α7nAChR) (- / -) gene knockout rats. The expressions of tumor necrosis factor alpha (TNF-ɑ) and phosphorylated-Janus kinase2 (p-JAK2), phosphorylated-signal transducer and activator of transcription3(p-STAT3) in the hypothalamus, amygdala, and hippocampus were detected by Western blot. We observed that LPS significantly decreased the sucrose preference, the time of into the open arms in the elevated plus maze, and the number of crossing and reaping in the open field test. TaVNS treatment improves these depression-like behaviors, but taVNS is not effective in α7nAChR (- / -) gene knockout rats. The expression of TNF-ɑ significantly increased, and the expression of p-Jak2 and p-STAT3 markedly decreased in the hypothalamus and amygdala induced by LPS. TaVNS could significantly reverse the abovementioned phenomena but had rare improvement effect for α7nAChR (- / -) rats. We conclude that the antidepressant effect of taVNS for LPS-induced depressive rats is related to α7nAchR/JAK2 signal pathway in the hypothalamus and amygdala.

Psychosocial status and COVID-19 outcome are significantly associated

Covid-19 pandemic raised both physical and mental threat to human. Globally, 607,497,755cases of infection and 6,492,948 deaths were recorded until August, 2022. The psychosocial-conditions in pre-infection-period might influence disease. Here, we delineate the impact of socio-economic status, pre- or post- Covid-19 psychosocial and other factors (lockdown/self-isolation/diagnosis)on this disease outcome. Pre-Covid mental-status (depression-anxiety, tobacco-smoking and suicide-mortality), quality-of-life (QOL) and Global-Health-Security (GHS) were correlated with total-infection and case-fatality-rate (CFR) in > 170 countries. The database of World-Health-Organization/World-Bank/United-Nations and the Johns-Hopkins-Center for Health-Security was utilized. The Student's t test, multivariate-ANOVA, correlation and linear-regression were performed. Psychological wellbeing indicators (happiness/GSH/QOL) and mental-impairments like depression-anxiety positively correlated with infection and CFR (p < 0.05-p < 0.001). The happiness-index positively associated with QOL/GSH/anxiety and depression. Higher CFR was noticed in congested/populated territories. Canonical regression strongly suggests this result. Variable host-virus interactions associated with race/ethnicity and body-composition. Positive correlations between mental state-QOL and anxiety-depression paralleled with adverse outcome of Covid-19.

Exploring the potential antidepressant mechanisms of ibuprofen and celecoxib based on network pharmacology and molecular docking

BACKGROUND

Evidence has shown that ibuprofen and celecoxib are effective in improving depressive symptoms, but their mechanisms of action are unclear. In this study, we aimed to determine the relationship between these two drugs and depressive disorder (DD) and elucidate potential mechanisms of action.

METHODS

Relevant targets for ibuprofen, celecoxib, and DD were obtained and screened from multiple online drug and disease public databases. A protein-protein interaction network was obtained. The Centiscape and CytoHubba plug-ins were applied to screen for core targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed. Molecular docking was performed to predict the binding of ibuprofen and celecoxib to core targets. Examined the differences in core target protein expression between DD patients (DDs, n = 18) and healthy controls (HCs, n = 16) as a further experimental validation of the network pharmacology results.

RESULTS

In total, 220 potential targets for ibuprofen and 316 potential targets for celecoxib were identified and associated with DD. The antidepressant effects of both drugs involve many key targets in pathways such as "pathways in cancer" and "neuroactive ligand-receptor interaction," including ALB, BCL2, MAPK3, SRC, STAT3, EGFR, and PPARG. The binding affinity of ALB with ibuprofen is the strongest, and it is connected only by hydrophobic interactions. Celecoxib exhibits higher affinity at multiple targets such as SRC, EGFR, and PPARG, with stronger and more specific intermolecular interactions, including salt bridges and halogen bonds. Clinical trials have found that serum ALB expression in DDs is significantly lower than that in HCs (t = 6.653, p < 0.001), further confirming the potential role of ibuprofen in DD.

CONCLUSIONS

Ibuprofen and celecoxib primarily exert their antidepressant effects through targets and pathways related to inflammation, neural signaling, and cancer, with celecoxib showing a stronger potential antidepressant effect. The expression difference of the core target ALB between depression and healthy individuals further supports the potential effect of the drug on DD. Our findings propose new treatment strategies, support the link between inflammation and depression, and encourage reassessing existing medications for depression.

The pathogenesis of depression: Roles of connexin 43-based gap junctions and inflammation

BACKGROUND

Depression is a leading chronic mental illness worldwide, characterized by anhedonia and pessimism. Connexin is a kind of widely distributed protein in the body. Connexin 43 (Cx43) plays an important role in the pathogenesis of depression. Growing evidence has indicated that inflammation is closely associated with neuropsychiatric diseases such as depression. Inflammation occurs in patients with mood disorders, and symptomatic relief after multiple treatments is often accompanied by proinflammatory restoration. In this study, we sought to determine the upstream and downstream relationship of Cx43 abnormalities and peripheral inflammation in inducing depression.

METHODS AND RESULTS

Gap27, as a Cx43 mimetic peptide, specifically blocks Cx43 gap junction channels in the brain. The mice were treated with injection of Gap27 into the prefrontal cortex (PFC), conditional knockout of Cx43 in the PFC, and lipopolysaccharide (LPS) intraperitoneal injection. Our results revealed that the treatments gave rise to the depressive-like behavior occurrence in mice, including reducing the sucrose preference and spontaneous activities, and increasing immobility time in the forced swimming test. Functional blockade of Cx43 induced abnormal expression of peripheral inflammatory cytokines including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, IL-2, IL-10, and IL-18. Furthermore, depression associated with peripheral inflammation derived from LPS intraperitoneal injection significantly reduced the Cx43 expression and the diffusion distance of gap junction channel permeability dye in the PFC.

CONCLUSION

These results showed that blockade of Cx43 in the PFC and peripheral inflammation are complicatedly intertwined, and reinforcing each other during the induction of depression.

Dietary Magnesium Intake in Relation to Depression in Adults: A GRADE-Assessed Systematic Review and Dose-Response Meta-analysis of Epidemiologic Studies

CONTEXT

The relation of magnesium (Mg) intake with depression was previously investigated by meta-analyses. However, due to limited data, a dose-response analysis was not performed.

OBJECTIVE

Considering the recently published articles, a systematic review and dose-response meta-analysis was conducted to summarize the relation of dietary Mg intake with depression in adults.

DATA SOURCES

Medline (PubMed), ISI Web of Science, Scopus, and Google Scholar were comprehensively searched up to August 2023.

DATA EXTRACTION

Observational studies that reported the relation of dietary Mg intake and depression in adults were included and their data were extracted.

DATA ANALYSIS

A total of 63 214 participants from 10 cross-sectional and 3 cohort studies were included in the current study. Pooling 15 effect sizes from 12 studies (including 50 275 participants) revealed that individuals with the highest Mg intake had a 34% lower risk of depression, compared with those with the lowest Mg intake (RR: 0.66; 95% CI: 0.57, 0.78). Moreover, the linear dose-response analysis revealed that each 100-mg/d increment in Mg intake was associated with a 7% reduced risk of depression (RR: 0.93; 95% CI: 0.90, 0.96). Additionally, based on nonlinear dose-response analysis, increasing Mg intake from 170 to 370 mg/d was associated with a reduced risk of depression. Analyses were also conducted on 9 studies (49 558 participants) with representative populations, and similar results were found in the meta-analysis (RR: 0.71; 95% CI: 0.61, 0.83) and linear (RR: 0.93; 95% CI: 0.90, 0.96) and nonlinear dose-response analysis.

CONCLUSION

The current study shows an inverse dose-dependent association between dietary Mg intakes and risk of depression in both a general and representative population of adults in a dose-response manner.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42024506570.

Tofacitinib prevents depressive-like behaviors through decreased hippocampal microgliosis and increased BDNF levels in both LPS-induced and CSDS-induced mice

Depressive disorders are a global mental health challenge that is closely linked to inflammation, especially in the post-COVID-19 era. The JAK-STAT pathway, which is primarily associated with inflammatory responses, is not fully characterized in the context of depressive disorders. Recently, a phase 3 retrospective cohort analysis heightened that the marketed JAK inhibitor tofacitinib is beyond immune diseases and has potential for preventing mood disorders. Inspired by these clinical facts, we investigated the role of the JAK-STAT signaling pathway in depression and comprehensively assessed the antidepressant effect of tofacitinib. We found that aberrant activation of the JAK-STAT pathway is highly conserved in the hippocampus of classical depressive mouse models: LPS-induced and chronic social defeat stress (CSDS)-induced depressive mice. Mechanistically, the JAK-STAT pathway mediates proinflammatory cytokine production and microgliosis, leading to synaptic defects in the hippocampus of both depressive models. Remarkably, the JAK inhibitor tofacitinib effectively reverses these phenomena, contributing to its antidepressant effect. These findings indicate that the JAK/STAT pathway could be implicated in depressive disorders, and suggest that the JAK inhibitor tofacitinib has a potential translational implication for preventing mood disorders far beyond its current indications.

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

ETHNOPHARMACOLOGICAL RELEVANCE

Ashwagandha (Withania somnifera (L.) Dunal) root or whole-plant extracts are used to treat anxiety, insomnia, and other nervous system disturbances.

AIM OF THE STUDY

We evaluated the neuroprotective and antidepressant effects of ashwagandha root extract (ARE) on corticosterone-exposed HT-22 cells and unpredictable chronic mild stress (UCMS)-challenged mice.

MATERIALS AND METHODS

The neuroprotective properties of ARE containing withanolide A were assessed in HT-22 cells 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.

RESULTS

In HT-22 cells, ARE (100 and 200 μg/mL) and its constituent, withanolide A (1.56 and 3.12 μg/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 100 mg/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).

CONCLUSION

These results indicate that ARE containing withanolide A exhibits notable neuroprotective and antidepressant properties.

Role of the gut microbiome in psychological symptoms associated with inflammatory bowel diseases

The brain-gut axis constitutes the basis for the bidirectional communication between the central nervous system and the gastrointestinal tract driven by neural, hormonal, metabolic, immunological, and microbial signals. Alterations in the gut microbiome composition as observed in inflammatory bowel diseases can modulate brain function and emerging empirical evidence has indicated that interactions among the brain-gut microbiome-axis seem to play a significant role in the pathogenesis of both inflammatory bowel diseases and psychiatric disorders and their comorbidity. Yet, the immunological and molecular mechanisms underlying the co-occurrence of inflammatory bowel diseases and psychological symptoms are still poorly understood. The aim of this narrative review is to highlight contemporary empirical findings supporting a pivotal role of the gut microbiome in the pathophysiology of highly prevalent neuropsychiatric symptoms in inflammatory bowel diseases such as fatigue, depression, and anxiety. Finally, we focus on microbiome modulation as potential treatment option for comorbid neuropsychiatric symptoms in immune-mediated diseases and especially in inflammatory bowel diseases. High-quality clinical trials are required to clarify how microbiome modulation through dietary interventions or probiotic, prebiotic or synbiotic treatment can be used clinically to improve mental health and thus quality of life of patients with inflammatory bowel diseases.

Understanding the bidirectional association between obesity and risk of psychological distress and depression in young adults in the US: available evidence, knowledge gaps, and future directions

While the physical health effects of obesity are well-characterized, an emerging branch of research has shown that obesity additionally plays a critical role in one's mental health. Young adults, in a pivotal transition phase in their lives, may be particularly prone to the concurrent effects of obesity and adverse mental health outcomes. The purpose of this review is to comprehensively examine existing data regarding the connection between obesity and two widely validated measures of mental health: psychological distress and depression. The connection between mental health outcomes and obesity is mediated by a complex interplay between biological and sociocultural factors, which is explored in this review with particular focus on younger adults aged 20-39. Further, the impact of several demographic factors including race/ethnicity, gender, and immigration status are examined closely. To our knowledge, this review is one of the first efforts to integrate existing knowledge between obesity and mental health, with particular regard for young adults and the impact of other key sociodemographic characteristics. This review has important implications at the interface of two of the most pressing public health crises in the United States.

miR-26a-5p/ADAM17-Mediated Proteolysis of TREM2 Regulates Neuroinflammation in Hypertensive Mice Following Lead Exposure

Hypertension is not merely a vascular disorder but a significant risk factor for neural impairment. Moreover, healthcare for the hypertensive population with environmental or occupational pollutants has become an issue of increasing concern in public health. As a traditional neurotoxic heavy metal, Pb exposure results in neuroinflammation as well as neurodegenerative diseases. The current study aimed to investigate the mechanisms of neuroinflammation in hypertensive mice exposed to Pb. We demonstrated that hypertension exacerbated Pb-induced neuroinflammation in the prefrontal cortex (PFC), hippocampus, and hypothalamus, as evidenced by increased levels of proinflammatory cytokines (IL-6 and TNF-α) and decreased levels of anti-inflammatory cytokines (CD206 and IL-10). Additionally, hypertension enhanced the neuroinflammatory response in microglia, as indicated by similar changes in cytokine expression in an in vitro cell model. Importantly, we found that TREM2, a key regulator of microglial inflammation, was downregulated in hypertensive mice with Pb exposure. This decline in TREM2 expression was associated with increased proteolysis of TREM2 by a disintegrin and metalloproteases 10 (ADAM10) as well as a disintegrin and metalloproteases 17 (ADAM17), in which ADAM17 was verified as the main cleavage enzyme in terms of TREM2 proteolytic cleavage in hypertensive mice following Pb exposure. Furthermore, we identified miR-26a-5p as a potential regulator of ADAM17 expression, suggesting a potential mechanism for the downregulation of TREM2 in this context. Our findings provided new insights into the complex interplay between hypertension, Pb exposure, and neuroinflammation as well as highlight the potential role of TREM2, ADAM17, and miR-26a-5p as therapeutic targets for neuroinflammation in hypertensive populations with Pb exposure.

Comparison of Immune and Systemic Inflammation Parameters in Patients with a Depressive Episode in Bipolar Disorder and Major Depressive Disorder: A Scoping Review

BACKGROUND

Many studies have aimed to investigate and compare immune system and systemic inflammation parameters in patients with bipolar disorder (BD) and major depressive disorder (MDD) suffering from a depressive episode. However, no systematic review of the results has been conducted so far.

AIM

The aim of this study was to conduct a scoping review of research studies comparing immune and systemic inflammation parameters in patients with BD and MDD during a depressive episode.

METHODS

The search for studies was conducted in the Medline and eLIBRARY databases for the period from January 1994 to December 2022. Open-access articles written in English and Russian were selected. The review included original studies that compared groups of patients with BD and MDD (diagnosed based on the DSM-IV, DSM-5, or ICD-10 criterion) by immune and systemic inflammation parameters (such as the counts, ratio, and functions of blood cells, erythrocyte sedimentation rate, concentrations of immunoglobulins, cytokines, acute phase proteins, complement components, and autoantibodies).

RESULTS

The review included 24 studies. Current depressive episodes in patients with BD were associated with higher concentrations of chemokines (C-C motif chemokine ligand 3 (CCL3), CCL4, CCL5, CCL11), platelet-derived growth factor B, and interleukin 9 (IL-9) (two studies in each case), whereas patients with MDD tended to have higher concentrations of soluble tumor necrosis factor receptor 1 and immunoglobulin G to oxidized low-density lipoproteins (two studies each). Patients with BD and MDD had comparable concentrations of IL-8 (five studies); IL-2 and IL-10 (four studies each); IL-13 and gamma interferon (three studies each); IL-17, IL-1Rα, the vascular endothelial growth factor, as well as white blood cells, monocyte, and platelet counts (two studies each). Contradictory results were obtained for the levels of tumor necrosis factor-α (the concentrations did not differ in five studies, were elevated in BD patients in five studies, were elevated in MDD patients in two studies), IL-6 (the concentrations did not differ in eight studies and were elevated in BD patients in four studies), C-reactive protein (the concentrations did not differ in six studies, were elevated in BD patients in two studies), IL-4 (the concentrations did not differ in three studies and were elevated in MDD patients in two studies), IL-1β and the neutrophil count (the levels did not differ in one study each and were elevated in BD patients in two studies). Several studies have demonstrated an association between immune and systemic inflammation parameters and the severity of depressive and anxiety symptoms, melancholic depression, age of mood disorder onset, body mass index, and imipramine equivalent.

CONCLUSION

Some immune and systemic inflammation parameters are associated with a current depressive episode in patients with MDD or BD. These parameters may be considered as potential biomarkers for a differential diagnosis of these disorders.

Dazhu Hongjingtian injection attenuated alcohol-induced depressive symptoms by inhibiting hippocampus oxidative stress and inflammation through Nrf2/HO-1/NLRP3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Alcoholic depression, a disorder of the central nervous system, is characterized by alcohol abuse, which causes blood-brain barrier disruption and oxidative damage in the brain. The rhizome of Rhodiola crenulate, from which Dazhu Hongjingtian Injection (DZHJTI) is derived, has been traditionally employed in ethnopharmacology to treat neurological disorders due to its neuroprotective, anti-inflammatory, and antioxidant properties. However, the exact mechanism by which DZHJTI alleviates alcoholic depression remains unclear.

AIM OF THE STUDY

This study aimed to investigate the antidepressant effects of DZHJTI and its underlying mechanisms in a mouse model of alcohol-induced depression.

MATERIALS AND METHODS

A model of alcoholic depression was established using C57BL/6J mice, and the effects of DZHJTI on depression-like behaviors induced by alcohol exposure were assessed through behavioral experiments. Histopathological examination was conducted to observe nerve cell damage and microglial activation in the hippocampal region. Oxidative stress indices in the hippocampus, inflammatory factors, and serum levels of dopamine (DA) and 5-hydroxytryptamine (5-HT) were measured using ELISA. Expression of proteins related to the Nrf2/HO-1/NLRP3 signaling pathway was determined by Western blot analysis.

RESULTS

DZHJTI attenuated depression-like behaviors, neuronal cell damage, oxidative stress levels, inflammatory responses, and microglial activation. It also restored levels of brain-derived neurotrophic factor, brain myelin basic protein, DA, and 5-HT in mice with chronic alcohol exposure. After DZHJTI treatment, the expressions of Nuclear Respiratory Factor 2 (Nrf2) and Heme Oxygenase-1 (HO-1) increased in the hippocampus, whereas the levels of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3), apoptosis-associated speck-like protein containing CARD, cleaved caspase-1, interleukin (IL)-1β, and IL-18 decreased.

CONCLUSIONS

DZHJTI ameliorates alcohol-induced depressive symptoms in mice through its antioxidant and anti-inflammatory effects, involving mechanisms associated with the Nrf2/HO-1/NLRP3 signaling pathway. This study highlights the potential of DZHJTI as a therapeutic option for alcohol-related depression and suggests the scope for future research to further elucidate its mechanisms and broader clinical applications.

Chronic corticosterone exposure causes anxiety- and depression-related behaviors with altered gut microbial and brain metabolomic profiles in adult male C57BL/6J mice

Chronic exposure to glucocorticoids in response to long-term stress is thought to be a risk factor for major depression. Depression is associated with disturbances in the gut microbiota composition and peripheral and central energy metabolism. However, the relationship between chronic glucocorticoid exposure, the gut microbiota, and brain metabolism remains largely unknown. In this study, we first investigated the effects of chronic corticosterone exposure on various domains of behavior in adult male C57BL/6J mice treated with the glucocorticoid corticosterone to evaluate them as an animal model of depression. We then examined the gut microbial composition and brain and plasma metabolome in corticosterone-treated mice. Chronic corticosterone treatment resulted in reduced locomotor activity, increased anxiety-like and depression-related behaviors, decreased rotarod latency, reduced acoustic startle response, decreased social behavior, working memory deficits, impaired contextual fear memory, and enhanced cued fear memory. Chronic corticosterone treatment also altered the composition of gut microbiota, which has been reported to be associated with depression, such as increased abundance of Bifidobacterium, Turicibacter, and Corynebacterium and decreased abundance of Barnesiella. Metabolomic data revealed that long-term exposure to corticosterone led to a decrease in brain neurotransmitter metabolites, such as serotonin, 5-hydroxyindoleacetic acid, acetylcholine, and gamma-aminobutyric acid, as well as changes in betaine and methionine metabolism, as indicated by decreased levels of adenosine, dimethylglycine, choline, and methionine in the brain. These results indicate that mice treated with corticosterone have good face and construct validity as an animal model for studying anxiety and depression with altered gut microbial composition and brain metabolism, offering new insights into the neurobiological basis of depression arising from gut-brain axis dysfunction caused by prolonged exposure to excessive glucocorticoids.

Microbiota-gut-brain axis: Natural antidepressants molecular mechanism

BACKGROUND

Major depressive disorder (MDD) is a severe mental health condition characterized by persistent depression, impaired cognition, and reduced activity. Increasing evidence suggests that gut microbiota (GM) imbalance is closely linked to the emergence and advancement of MDD, highlighting the potential significance of regulating the "Microbiota-Gut-Brain" (MGB) axis to impact the development of MDD. Natural products (NPs), characterized by broad biological activities, low toxicity, and multi-target characteristics, offer unique advantages in antidepressant treatment by regulating MGB axis.

PURPOSE

This review was aimed to explore the intricate relationship between the GM and the brain, as well as host responses, and investigated the mechanisms underlying the MGB axis in MDD development. It also explored the pharmacological mechanisms by which NPs modulate MGB axis to exert antidepressant effects and addressed current research limitations. Additionally, it proposed new strategies for future preclinical and clinical applications in the MDD domain.

METHODS

To study the effects and mechanism by which NPs exert antidepressant effects through mediating the MGB axis, data were collected from Web of Science, PubMed, ScienceDirect from initial establishment to March 2024. NPs were classified and summarized by their mechanisms of action.

RESULTS

NPs, such as flavonoids,alkaloids,polysaccharides,saponins, terpenoids, can treat MDD by regulating the MGB axis. Its mechanism includes balancing GM, regulating metabolites and neurotransmitters such as SCAFs, 5-HT, BDNF, inhibiting neuroinflammation, improving neural plasticity, and increasing neurogenesis.

CONCLUSIONS

NPs display good antidepressant effects, and have potential value for clinical application in the prevention and treatment of MDD by regulating the MGB axis. However, in-depth study of the mechanisms by which antidepressant medications affect MGB axis will also require considerable effort in clinical and preclinical research, which is essential for the development of effective antidepressant treatments.

Rehmannia glutinosa DC.-Lilium lancifolium Thunb. in the treatment of depression: a comprehensive review and perspectives

Background

In recent years, the incidence of depression, recognized as a serious psychological disorder, has escalated rapidly. Rehmannia glutinosa DC. (Scrophulariaceae; Rehmanniae Radix, Crude drug) and Lilium lancifolium Thunb. (Liliaceae; Lilii bulbus, Crude drug) constitute a classic anti-depressant combination, exhibiting pharmacological effects that include anti-depressive, anti-anxiety, and anti-inflammatory properties. Current clinical studies have demonstrated that Baihe Dihuang Decoction, a traditional Chinese herbal compound, is effective in treating depression. However, the majority of scholars have predominantly examined Rehmannia glutinosa and Lilium in isolation, and a comprehensive elucidation of their principal active metabolites and pharmacological mechanisms remains lacking.

Methods

A comprehensive literature search was conducted as of 29 September 2024, utilizing databases such as PubMed, CNKI, Wanfang Data, Baidu Scholar, and Google Scholar. Additionally, classical texts on Chinese herbal medicine, the Chinese Pharmacopoeia, as well as doctoral and master's theses, were included in the collected materials. The search employed specific terms including "R. glutinosa," "Lilium," "Baihe Dihuang decoction," "application of Baihe Dihuang decoction," "pathogenesis of depression," and "pharmacological action and mechanism of depression.

Results

This paper reviewed the traditional applications and dosages of the R. glutinosa-Lilium as documented in Chinese medical classics, thereby establishing a foundation for the contemporary development and clinical application of the classical formula Baihe Dihuang Decoction. Additionally, recent years have seen a comprehensive review of the pharmacological effects and mechanisms of R. glutinosa-Lilium and its principal metabolites in the context of depression.

Conclusion

This paper has reviewed the active metabolites of R. glutinosa-Lilium and demonstrated its efficacy in the treatment of depression, as well as its role in modulating the underlying mechanisms of the disorder. The findings aim to serve as a reference for further research into the mechanisms of depression, its clinical applications, and the development of novel therapeutic agents.

The association between triglyceride glucose index and suicidal ideation in American adults: Results from NHANES 2005 to 2018

Previous studies have shown a significant association between the triglyceride glucose index (TyG) and suicidal ideation in Korean women. However, this association has not yet been examined among American adults. This study aims to investigate the association between TyG and suicidal ideation using data from the National Health and Nutrition Examination Survey. The National Health and Nutrition Examination Survey database from 2005 to 2018 was used, including samples ≥20 years old. Suicidal ideation was assessed through questionnaires, and the TyG was derived from fasting triglyceride and glucose measurements. Weighted logistic regression models were used to analyze the relationship between the TyG and suicidal ideation. Generalized additive model curves explored the nonlinear relationship, while stratified and sensitivity analyses assessed potential interactions and the robustness of the findings. A significance level of P < .05 was considered statistically significant. A total of 15,694 participants were enrolled, of whom 3.67% participants showed suicidal ideation. The mean TyG index for participants with or without suicidal ideation was 8.82 ± 0.76, 8.65 ± 0.68, respectively (P < .001). Multivariable logistic regression showed that a higher level of TyG were associated with a higher likelihood of suicidal ideation (OR = 1.20; 95% CI, 1.05-1.38) after full adjustment. Subgroup analysis and interaction tests showed no significant correlation between gender, age, race, marital status, education, body mass index, poverty income ratio, smoking status, drinking status, diabetes, hypertension, stroke, and cancer (P > .05 for all interactions). Our findings confirm a significant and positive association between the TyG and suicidal ideation among American adults. Further large-scale prospective studies are needed to analyze the role of TyG in suicidal ideation.

Huangqin Qingre Chubi Capsule improves rheumatoid arthritis accompanied depression through the Wnt1/β-catenin signaling pathway

AIM OF THE STUDY

Research on the mechanism of Huangqin Qingre Chubi Capsules (HQC) in improving rheumatoid arthritis accompanied depression (RA-dep) model rats.

METHODS

We employed real-time qPCR (RT-qPCR), western blotting (WB), confocal microscopy, bioinformatics, and other methods to investigate the anti-RA-dep effects of HQC and its underlying mechanisms.

RESULTS

HQC alleviated the pathological indexes of inflammation and depression in RA-dep model rats, decreased the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, increased the levels of norepinephrine(NE) and serotonin(5-HT), and improved the injury of hippocampus. The analysis of network pharmacology suggests that HQC may target the Wnt/β-catenin pathway in the treatment of RA-dep. Furthermore, molecular dynamics simulations revealed a strong affinity between HQC and the Wnt1 molecule. RT-qPCR and Western Blot (WB) experiments confirmed the critical role of the Wnt1/β-catenin signaling pathway in the treatment of RA-dep model rats with HQC. In vitro, the HQC drug-containing serum (HQC-serum) activates the Wnt1/β-catenin signaling pathway in hippocampal cells and, in conjunction with Wnt1, ameliorates RA-dep. In summary, HQC exerts its anti-inflammatory and antidepressant effects in the treatment of RA-dep by binding to Wnt1 and regulating the Wnt1/β-catenin signaling pathway.

CONCLUSIONS

HQC improved the inflammatory reaction and depression-like behavior of RA-dep model rats by activating Wnt1/β-catenin signal pathway. This study revealed a new pathogenesis of RA-dep and contributes to the clinical promotion of HQC in the treatment of RA-dep.

Risk Factors for Depression in Patients With Knee Osteoarthritis: A Systematic Review and Meta-analysis

BACKGROUND

Knee osteoarthritis (KOA) is a widespread chronic condition. Depression frequently occurs among patients with KOA. The objective of this meta-analysis was to identify risk factors associated with comorbid depression in patients with KOA.

MATERIALS AND METHODS

A comprehensive search of the PubMed/MEDLINE, Embase, Cochrane Library, and Web of Science databases was conducted for studies related to comorbid depression in patients with KOA. We conducted statistical analyses to obtain relevant results, followed by heterogeneity tests and assessment for publication bias.

RESULTS

The prevalence of comorbid depression among patients with KOA was 34% (95% CI, 28%-41%). Notable risk factors linked to comorbid depression in patients with KOA included female sex (relative risk [RR], 1.17; 95% CI, 1.11-1.23), obesity (mean difference [MD], 1.30; 95% CI, 0.88-1.71), use of analgesics (RR, 1.50; 95% CI, 1.38-1.63), comorbidities (MD, 0.20; 95% CI, 0.10-0.31), unmarried or widowed status (RR, 1.72; 95% CI, 1.56-1.91), bilateral knee pain (RR, 1.38; 95% CI, 1.11-1.71), high total Western Ontario and Mc-Master Universities Arthritis Index (WOMAC) score (MD, 14.92; 95% CI, 10.02-19.82), high WOMAC pain score (MD, 5.76; 95% CI, 2.86-8.67), low gait velocity (MD, -0.12; 95% CI, -0.16 to -0.09), and extended duration in the Timed Up and Go Test (MD, 1.56; 95% CI, 0.87-2.25).

CONCLUSION

Based on the current evidence, female sex, obesity, use of analgesics, comorbidities, unmarried or widowed status, bilateral knee pain, high total WOMAC score, high WOMAC pain score, low gait velocity, and prolonged time on the Timed Up and Go Test were identified as risk factors for depression in patients with KOA. Focus should be given to these aspects when preventing depression among these patients. [Orthopedics. 2024;47(5):e225-e232.].

Inflammation-stratified augmentation of vortioxetine with celecoxib: Results from a double-blind, randomized, placebo-controlled trial in major depressive disorder

Low-grade inflammation is considered as a pathophysiological mechanism in a subtype of patients with major depressive disorder (MDD). Anti-inflammatory drugs have shown efficacy in treating MDD. However, it remains unclear how to identify suitable patients for anti-inflammatory treatment of depression. This study investigates the predictive value of pre-treatment high-sensitivity C-Reactive Protein (hsCRP) stratification on the outcome of celecoxib augmentation of vortioxetine. The PREDDICT study was conducted as a randomized, double-blind, placebo-controlled 6-week trial on augmentation of vortioxetine with celecoxib between December 2017 and April 2020 at the University of Adelaide (Australia). The present analysis focusses on the question of whether the pre-treatment hsCRP measurement and stratification of patients to depression with inflammation (hsCRP >3 mg/L) or without inflammation (hsCRP ≤3 mg/L) has an impact on the outcome of anti-inflammatory treatment with celecoxib. A total of n = 119 mostly treatment-resistant MDD patients with moderate to severe symptomatology were recruited in the trial. There was no effect of treatment group (celecoxib or placebo), pre-treatment hsCRP strata (with/without inflammation), or interaction between the two terms on treatment outcome. The results of the current analysis do not support the hypothesis that pre-treatment hsCRP level is predictive for response to anti-inflammatory treatment with celecoxib in MDD patients. Further research is needed to identify appropriate biomarkers for the prediction of anti-inflammatory treatment outcome in depression. CLINICAL TRIALS REGISTRATION: Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617000527369p. Registered on 11 April 2017, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12617000527369p.

Association of statin use with risk of depression and anxiety: A prospective large cohort study

OBJECTIVES

To examine associations between regular statin use and the incidence of depression and anxiety.

METHODS

This cohort was based on UK Biobank participants without depression/anxiety recruited between 2006 and 2010. The self-reported regular statin use was collected at baseline. Depression and anxiety outcomes were assessed by diagnostic interviews (international classification of diseases codes) and nondiagnostic scales (mental well-being questionnaires). Cox proportional hazards models adjusted for a wide range of confounders were used to estimate associations of statins with incident depression/anxiety.

RESULTS

Among 363,551 eligible participants, 55,838 reported regular statin use. During a 13-year follow-up, 14,765 cases of depression and 15,494 cases of anxiety were identified. Compared with non-statin users, statin use was associated with reduced risk of depression (hazard ratio [HR]: 0.87; 95% confidence interval [CI]: 0.81, 0.94) and anxiety (HR: 0.90, 95% CI: 0.84, 0.97). Effects of statins on depression were consistent in sensitivity analyses and may be less influenced by unmeasured confounders. However, results of online survey data showed that statin use might not be associated with incident anxiety (HR: 0.96, 95% CI: 0.85, 1.09).

CONCLUSION

Regular statin use was associated with a lower risk of depression. No clear associations between statin use and anxiety were found.

"Inflamed" depression: A review of the interactions between depression and inflammation and current anti-inflammatory strategies for depression

Depression is a common mental disorder, the effective treatment of which remains a challenging issue worldwide. The clinical pathogenesis of depression has been deeply explored, leading to the formulation of various pathogenic hypotheses. Among these, the monoamine neurotransmitter hypothesis holds a prominent position, yet it has significant limitations as more than one-third of patients do not respond to conventional treatments targeting monoamine transmission disturbances. Over the past few decades, a growing body of research has highlighted the link between inflammation and depression as a potential key factor in the pathophysiology of depression. In this review, we first summarize the relationship between inflammation and depression, with a focus on the pathophysiological changes mediated by inflammation in depression. The mechanisms linking inflammation to depression as well as multiple anti-inflammatory strategies are also discussed, and their efficacy and safety are assessed. This review broadens the perspective on specific aspects of using anti-inflammatory strategies for treating depression, laying the groundwork for advancing precision medicine for individuals suffering from "inflamed" depression.

Association between dietary spermidine intake and depressive symptoms among US adults: National Health and Nutrition Examination Survey (NHANES) 2005-2014

BACKGROUND

Spermidine (SPD) has a number of advantageous effects, including life extension and neuroprotection. However, few observational studies have investigated the association of dietary SPD intake with depression.

METHODS

We used data from the 2005-2014 National Health and Nutrition Examination Survey (NHANES) and the corresponding Food Patterns Equivalents Database (FPED). SPD content of food groups from published data were merged with the appropriate FPED data to estimate the SPD intake for each subject. Patients with Patient Health Questionnaire-9 (PHQ-9) scores of 10 or above were thought to experience clinically relevant depression symptoms. Logistic regression, sensitivity analysis, and restricted cubic spline (RCS) were used.

RESULTS

Among the 19,306 participants, the overall prevalence of depression was 8.72 %. After controlling for relevant confounders, individuals in the highest tertile or quartile of total SPD and SPD derived from fruits, vegetables, cereals, nuts, eggs and seafood had a significantly lower prevalence of depression (OR total SPD = 0.77, 95 % CI: 0.63-0.93); OR fruit-sourced SPD = 0.81, 95 % CI: 0.68-0.95; OR vegetable-sourced SPD = 0.72, 95 % CI: 0.61-0.85; OR cereals-sourced SPD = 0.73,95 % CI:0.60-0.88; OR nuts- sourced SPD = 0.80, 95 % CI: 0.71-0.91; OR egg-sourced = 0.72, 95 % CI: 0.62-0.84 and OR seafood-sourced SPD = 0.65, 95 % CI: 0.55-0.77) comparing those in the lowest tertile or quartile.

CONCLOUSION

Our fndings reveal a negative association between dietary SPD intake and depression.

The causal relationship between major depression disorder and thyroid diseases: A Mendelian randomization study and mediation analysis

BACKGROUND

Studies have been conducted on the relationship between depression and thyroid diseases and function, its causal relationship remains unclear.

METHODS

Using summary statistics of genome-wide association studies of European and East Asian ancestry, we conducted 2-sample bidirectional Mendelian randomization to estimate the association between MDD and thyroid function (European: normal range TSH, T4, T3, fT4, TPOAb levels and TPOAb-positives; East Asian: T4) and thyroid diseases (hypothyroidism, hyperthyroidism, and Hashimoto's thyroiditis), and used Mediation analysis to evaluate potential mediators (alcohol intake, antidepressant) of the association and calculate the mediated proportions.

RESULTS

It was observed a significant causal association between MDD on hypothyroidism (P = 8.94 × 10-5), hyperthyroidism (P = 8.68 × 10-3), and hashimoto's thyroiditis (P = 3.97 × 10-5) among European ancestry, which was mediated by Alcohol intake (alcohol intake versus 10 years previously for hypothyroidism (P = 0.026), hashimoto's thyroiditis (P = 0.042), and alcohol intake frequency for hypothyroidism (P = 0.015)) and antidepressant (for hypothyroidism (P = 0.008), hashimoto's thyroiditis (P = 0.010)), but not among East Asian ancestry (PMDD-hypothyroidism = 0.016, but β direction was different; PMDD-hyperthyroidism = 0.438; PMDD-hashimoto's thyroiditis = 0.496). There was no evidence for bidirectional causal association between thyroid function mentioned above and MDD among both ancestry (all P > 0.05).

CONCLUSION

We importantly observed a significant causal association between MDD on risk of hypothyroidism, hyperthyroidism, and hashimoto's thyroiditis among European ancestry, and Alcohol intake and antidepressant as mediators for prevention of hypothyroidism, hashimoto's thyroiditis attributable to MDD.

Systemic immune inflammation index is a valuable marker for predicting hemodialysis patients with depression: a cross-sectional study

Objective

Maintenance hemodialysis (MHD) patients suffer from enormous physical, mental stress and poor quality of life, so an increasing number of patients are in a long-term state of depression. A prominent feature of MHD patients is chronic persistent inflammation, which is also an important mechanism for the onset of depression. Therefore, finding economically convenient inflammatory markers to predict and diagnose the onset of depression in MHD patients is of great value. As a novel inflammatory marker, systemic immune inflammation index (SII) can more comprehensively reflect the inflammation and immunity level of patients. This study aims to explore the relationship between SII and depressive symptoms in MHD patients.

Methods

A cross-sectional study was conducted on 206 MHD patients from three dialysis centers. Based on the Hospital Anxiety and Depression Scale (HADS) scores, patients were divided into non-depression and depression groups. Inter group comparison and multivariate logistic regression analysis were performed to determine whether SII is an independent risk factor for depression in MHD patients. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of SII on depression symptoms in MHD patients.

Results

According to the HADS scale score, 38.83% of the included patients were in a state of depression. After adjusting for all confounding factors, MHD patients with SII>963.93 had a 4.709 times higher risk of depression than those with SII ≤ 478.32 (OR=4.709, 95% CI 1.821-12.178, P<0.01). ROC analysis showed that SII>685.11 was the best cutoff value for MHD depression patients, and the area under the curve (AUC) was 0.681.

Conclusions

High SII is an independent risk factor for depressed MHD patients and an ideal inflammatory marker for predicting and identifying depression in MHD patients as assessed by the HADS scale.

The impact of adult neurogenesis on affective functions: of mice and men

In most mammals, new neurons are not only produced during embryogenesis but also after birth. Soon after adult neurogenesis was discovered, the influence of recruiting new neurons on cognitive functions, especially on memory, was documented. Likewise, the late process of neuronal production also contributes to affective functions, but this outcome was recognized with more difficulty. This review covers hypes and hopes of discovering the influence of newly-generated neurons on brain circuits devoted to affective functions. If the possibility of integrating new neurons into the adult brain is a commonly accepted faculty in the realm of mammals, the reluctance is strong when it comes to translating this concept to humans. Compiling data suggest now that new neurons are derived not only from stem cells, but also from a population of neuroblasts displaying a protracted maturation and ready to be engaged in adult brain circuits, under specific signals. Here, we discuss the significance of recruiting new neurons in the adult brain circuits, specifically in the context of affective outcomes. We also discuss the fact that adult neurogenesis could be the ultimate cellular process that integrates elements from both the internal and external environment to adjust brain functions. While we must be critical and beware of the unreal promises that Science could generate sometimes, it is important to continue exploring the potential of neural recruitment in adult primates. Reporting adult neurogenesis in humankind contributes to a new vision of humans as mammals whose brain continues to develop throughout life. This peculiar faculty could one day become the target of treatment for mental health, cognitive disorders, and elderly-associated diseases. The vision of an adult brain which never stops integrating new neurons is a real game changer for designing new therapeutic interventions to treat mental disorders associated with substantial morbidity, mortality, and social costs.

Depression clinical trials worldwide: a systematic analysis of the ICTRP and comparison with ClinicalTrials.gov

Major depressive disorder (MDD), commonly known as depression, affects over 300 million people worldwide as of 2018 and presents a wide range of clinical symptoms. The international clinical trials registry platform (ICTRP) introduced by WHO includes aggregated data from ClinicalTrials.gov and 17 other national registers, making it the largest clinical trial platform. Here we analysed data in ICTRP with the aim of providing comprehensive insights into clinical trials on depression. Applying a novel hidden duplicate identification method, 10,606 depression trials were identified in ICTRP, with ANZCTR being the largest non- ClinicalTrials.gov database at 1031 trials, followed by IRCT with 576 trials, ISRCTN with 501 trials, CHiCTR with 489 trials, and EUCTR with 351 trials. The top four most studied drugs, ketamine, sertraline, duloxetine, and fluoxetine, were consistent in both groups, but ClinicalTrials.gov had more trials for each drug compared to the non-ClinicalTrials.gov group. Out of 9229 interventional trials, 663 unique agents were identified, including approved drugs (74.5%), investigational drugs (23.2%), withdrawn drugs (1.8%), nutraceuticals (0.3%), and illicit substances (0.2%). Both ClinicalTrials.gov and non-ClinicalTrials.gov databases revealed that the largest categories were antidepressive agents (1172 in ClinicalTrials.gov and 659 in non-ClinicalTrials.gov) and nutrients, amino acids, and chemical elements (250 in ClinicalTrials.gov and 659 in non-ClinicalTrials.gov), indicating a focus on alternative treatments involving dietary supplements and nutrients. Additionally, 26 investigational antidepressive agents targeting 16 different drug targets were identified, with buprenorphine (opioid agonist), saredutant (NK2 antagonist), and seltorexant (OX2 antagonist) being the most frequently studied. This analysis addresses 40 approved drugs for depression treatment including new drug classes like GABA modulators and NMDA antagonists that are offering new prospects for treating MDD, including drug-resistant depression and postpartum depression subtypes.

A classic prescription alleviates inflammation in CUMS model mice via modulating MYDGF/MAP4K4/NF-κB signaling pathway, verified through UPLC-HRMS and proteomics analysis

Background

Xiaoyaosan (XYS), a renowned classical traditional Chinese medicinal formula utilized in addressing major depressive disorder (MDD), has garnered significant acclaim for its remarkable efficacy in clinical application. The onset of major depressive disorder (MDD) often correlates with chronic unpredictable mild stress (CUMS), a pivotal instigating factor in its development.Aim of the study: This study aims to clarify the potential anti-inflammatory mechanisms of XYS in treating CUMS model mice.

Materials and methods

Utilizing cutting-edge ultra high-performance liquid chromatography - high-resolution mass spectrometry (UPLC-HRMS), the active constituents of XYS were discerned, while employing proteomics analysis to delve into the potential mechanisms of its efficacy. Molecular docking studies, alongside subsequent in vivo experiments utilizing CUMS model mice, were conducted to corroborate the findings derived from the proteomics analysis.

Results

In vivo experiments demonstrated that XYS not only markedly ameliorated behavioral markers but also attenuated serum inflammatory markers and suppressed IL-6 and TNF-α expression within the brains of CUMS model mice. Proteomics analysis suggested that the pivotal anti-inflammatory mechanism of XYS against CUMS-induced damage might involve modulation of the MAPK signaling pathway. Utilizing UPLC-HRMS, the active constituents of XYS were successfully identified, while molecular docking investigations explored interactions between XYS and MYDGF, PKC, MAP4K4, P-p65, p65, P-IKBα, and IKBα. The findings revealed XYS's regulatory influence on the MYDGF/MAP4K4/NF-κB signaling cascade.

Conclusions

This study is the first to our knowledge to demonstrate that XYS can alleviate inflammation in CUMS model mice by modulating the MYDGF/MAP4K4/NF-κB signaling pathway.

Association between Regular Use of Analgesics before Cancer Diagnosis and Occurrence of Mood Disorders

We aimed to determine the relationship between the use of analgesics prescribed for pain management and the onset and progression of mood disorders using a large-scale cohort database. We calculated hazard ratios (HR) with 95% confidence intervals (CI) for patient risk of developing mood disorders based on age, income, health-related variables, disease history, Charlson comorbidity index, and analgesics prescription behavior (Models 1-3). Additionally, we determined the risk of mood disorder occurrence by age group (Model 4) using a proportional hazards regression model. The age- and income-adjusted HR (Model 1) was 1.8275. The age-, income-, BMI-, and physical-activity-adjusted HR (Model 2) was 1.882. The fully adjusted HR (Model 3) was 1.698. Compared with no analgesic use, nonregular use (HR = 1.386) and regular use (HR = 1.698) was associated with a higher risk of mood disorders. Among patients older than 50 years, those who participated in physical activity (less than five days) had a lower risk of mood disorders than those who did not. This suggests that it may be useful for preventing mood disorders in older cancer survivors. A high risk of comorbidities and regular use of analgesics are risk factors for developing mood disorders. Therefore, our results suggest that cancer survivors with a high risk of comorbidities and a history of regular analgesic use should undergo careful psychiatric consultation.

The antidepressant effect of Shexiang Baoxin Pills on myocardial infarction rats with depression may be achieved through the inhibition of the NLRP3 inflammasome pathway

BACKGROUND

Patients with myocardial infarction (MI) frequently experience a heightened incidence of depression, thereby increasing the risk of adverse cardiovascular events. Consequently, early detection and intervention in depressive symptoms among patients with MI are imperative. Shexiang Baoxin Pills (SBP), a Chinese patent medicine employed for the treatment of MI, exhibits diverse mechanisms targeting this condition. Nevertheless, its therapeutic efficacy on postmyocardial infarction depressive symptoms remains unclear. The aim of this study is to investigate the effectiveness and mechanism of SBP in managing depression during acute myocardial infarction (AMI).

METHODS

A rat model combining MI and depression was established, and the rats were randomly divided into four groups: the model (MOD) group, SBP group, Fluoxetine (FLX) group, and Sham group. After 28 days of drug intervention, cardiac function was assessed using echocardiography while behavior was evaluated through sucrose preference test (SPT), forced swimming test (FST), and open-field test (OFT). Additionally, levels of inflammatory factors in serum and hippocampus were measured along with NLRP3 inflammasome-related protein expression via Western blotting and immunofluorescence.

RESULTS

SBP can enhance cardiac function in rats with AMI and depression, while significantly ameliorating depressive-like behavior. Compared to the Sham group, levels of IL-1β, IL-18, TNF-α, and other inflammatory factors were markedly elevated in the MOD group. However, expressions of these inflammatory factors were reduced to varying degrees following treatment with SBP or FLX. Analysis of NLRP3 inflammasome-related proteins in the hippocampus revealed a significant upregulation of IL-1β, IL-18, NLRP3, ASC, caspase-1, and GSDMD in the MOD group; conversely, these measures were significantly attenuated after SBP intervention.

CONCLUSION

We have observed a significant amelioration in depression-like behavior upon SBP administration during the treatment of AMI, suggesting that this effect may be attributed to the inhibition of NLRP3-mediated pyroptosis. (The main findings are summarized in the graphical abstract in the supplementary file.).

Potential Plausible Role of Stem Cell for Treating Depressive Disorder: a Retrospective Review

Depression poses a significant threat to global physical and mental health, impacting around 3.8% of the population with a rising incidence. Current treatment options primarily involve medication and psychological support, yet their effectiveness remains limited, contributing to high relapse rates. There is an urgent need for innovative and more efficacious treatment modalities. Stem cell therapy, a promising avenue in regenerative medicine for a spectrum of neurodegenerative conditions, has recently garnered attention for its potential application in depression. While much of this work remains preclinical, it has demonstrated considerable promise. Identified mechanisms underlying the antidepressant effects of stem cell therapy encompass the stimulation of neurotrophic factors, immune function modulation, and augmented monoamine levels. Nonetheless, these pathways and other undiscovered mechanisms necessitate further investigation. Depression fundamentally manifests as a neurodegenerative disorder. Given stem cell therapy's success in addressing a range of neurodegenerative pathologies, it opens the door to explore its application in depression treatment. This exploration may include repairing damaged nerves directly or indirectly and inhibiting neurotoxicity. Nevertheless, significant challenges must be overcome before stem cell therapies can be applied clinically. Successful resolution of these issues will ultimately determine the feasibility of incorporating stem cell therapies into the clinical landscape. This narrative review provides insights into the progress of research, potential avenues for exploration, and the prevailing challenges in the implementation of stem cell therapy for treatment of depression.

Pharmacological mechanism of natural antidepressants: The role of mitochondrial quality control

BACKGROUND

Depression is a mental illness characterized by persistent sadness and a reduced capacity for pleasure. In clinical practice, SSRIs and other medications are commonly used for therapy, despite their various side effects. Natural products present distinct advantages, including synergistic interactions among multiple components and targeting multiple pathways, suggesting their tremendous potential in depression treatment. Imbalance in mitochondrial quality control (MQC) plays a significant role in the pathology of depression, emphasizing the importance of regulating MQC as a potential intervention strategy in addressing the onset and progression of depression. However, the role and mechanism through which natural products regulate MQC in depression treatments still need to be comprehensively elucidated, particularly in clinical and preclinical settings.

PURPOSE

This review was aimed to summarize the findings of recent studies and outline the pharmacological mechanisms by which natural products modulate MQC to exert antidepressant effects. Additionally, it evaluated current research limitations and proposed new strategies for future preclinical and clinical applications in the depression domain.

METHODS

To study the main pharmacological mechanisms underlying the regulation of MQC by natural products in the treatment of depression, we conducted a thorough search across databases such as PubMed, Web of Science, and ScienceDirect databases to classify and summarize the relationship between MQC and depression, as well as the regulatory mechanisms of natural products.

RESULTS

Numerous studies have shown that irregularities in the MQC system play an important role in the pathology of depression, and the regulation of the MQC system is involved in antidepressant treatments. Natural products mainly regulate the MQC system to induce antidepressant effects by alleviating oxidative stress, balancing ATP levels, promoting mitophagy, maintaining calcium homeostasis, optimizing mitochondrial dynamics, regulating mitochondrial membrane potential, and enhancing mitochondrial biogenesis.

CONCLUSIONS

We comprehensively summarized the regulation of natural products on the MQC system in antidepressants, providing a unique perspective for the application of natural products within antidepressant therapy. However, extensive efforts are imperative in clinical and preclinical investigations to delve deeper into the mechanisms underlying how antidepressant medications impact MQC, which is crucial for the development of effective antidepressant treatments.

Use of Extracellular Monomeric Ubiquitin as a Therapeutic Option for Major Depressive Disorder

Major depressive disorder (MDD) is a mood disorder that has become a global health emergency according to the World Health Organization (WHO). It affects 280 million people worldwide and is a leading cause of disability and financial loss. Patients with MDD present immunoendocrine alterations like cortisol resistance and inflammation, which are associated with alterations in neurotransmitter metabolism. There are currently numerous therapeutic options for patients with MDD; however, some studies suggest a high rate of therapeutic failure. There are multiple hypotheses explaining the pathophysiological mechanisms of MDD, in which several systems are involved, including the neuroendocrine and immune systems. In recent years, inflammation has become an important target for the development of new therapeutic options. Extracellular monomeric ubiquitin (emUb) is a molecule that has been shown to have immunomodulatory properties through several mechanisms including cholinergic modulation and the generation of regulatory T cells. In this perspective article, we highlight the influence of the inflammatory response in MDD. In addition, we review and discuss the evidence for the use of emUb contained in Transferon as a concomitant treatment with selective serotonin reuptake inhibitors (SSRIs).

Bovine colostrum supplementation as a new perspective in depression and substance use disorder treatment: a randomized placebo-controlled study

Introduction

This randomized, placebo-controlled, double-blind, parallel study aimed to evaluate the effect of 3-month supplementation of bovine colostrum (BOV-COL; 8x400 mg per day) on the outcomes of depression treatment in hospitalized patients with substance use disorder (SUD). The hypothesis is that BOV-COL supplementation as an add-on treatment results in favorable alternations in selected blood inflammatory markers or neurotransmitters, leading to better depression treatment outcomes compared with placebo (PLA).

Methods

Patients with a Minnesota Multiphasic Personality Inventory-2 score ≥60 points were enrolled. Twenty-nine participants (n=18 in the BOV-COL group and n=11 in the PLA group) completed the protocol.

Results

The mean Beck Depression Inventory-II score was significantly reduced after supplementation in both groups. However, the mean 17-point Hamilton Depression Rating Scale score was decreased in the BOV-COL group, but not in the PLA group. In the BOV-COL group, there was a reduction in interleukin (IL)-1, IL-6, IL-10, the IL-6:IL-10 ratio, IL-17, and tumor necrosis factor alpha (TNF-α), while in the PLA group only IL-6 decreased. Favorable alternations in the total count and differentials of white blood cell subsets were more pronounced in the BOV-COL. There were no changes in neurotransmitter concentrations.

Conclusions

BOV-COL supplementation is a promising add-on therapy in patients with depression and SUD.

Omics approaches open new horizons in major depressive disorder: from biomarkers to precision medicine

Major depressive disorder (MDD) is a recurrent episodic mood disorder that represents the third leading cause of disability worldwide. In MDD, several factors can simultaneously contribute to its development, which complicates its diagnosis. According to practical guidelines, antidepressants are the first-line treatment for moderate to severe major depressive episodes. Traditional treatment strategies often follow a one-size-fits-all approach, resulting in suboptimal outcomes for many patients who fail to experience a response or recovery and develop the so-called "therapy-resistant depression". The high biological and clinical inter-variability within patients and the lack of robust biomarkers hinder the finding of specific therapeutic targets, contributing to the high treatment failure rates. In this frame, precision medicine, a paradigm that tailors medical interventions to individual characteristics, would help allocate the most adequate and effective treatment for each patient while minimizing its side effects. In particular, multi-omic studies may unveil the intricate interplays between genetic predispositions and exposure to environmental factors through the study of epigenomics, transcriptomics, proteomics, metabolomics, gut microbiomics, and immunomics. The integration of the flow of multi-omic information into molecular pathways may produce better outcomes than the current psychopharmacological approach, which targets singular molecular factors mainly related to the monoamine systems, disregarding the complex network of our organism. The concept of system biomedicine involves the integration and analysis of enormous datasets generated with different technologies, creating a "patient fingerprint", which defines the underlying biological mechanisms of every patient. This review, centered on precision medicine, explores the integration of multi-omic approaches as clinical tools for prediction in MDD at a single-patient level. It investigates how combining the existing technologies used for diagnostic, stratification, prognostic, and treatment-response biomarkers discovery with artificial intelligence can improve the assessment and treatment of MDD.

Comprehensive Strategies for Metabolic Syndrome: How Nutrition, Dietary Polyphenols, Physical Activity, and Lifestyle Modifications Address Diabesity, Cardiovascular Diseases, and Neurodegenerative Conditions

Several hallmarks of metabolic syndrome, such as dysregulation in the glucose and lipid metabolism, endothelial dysfunction, insulin resistance, low-to-medium systemic inflammation, and intestinal microbiota dysbiosis, represent a pathological bridge between metabolic syndrome and diabesity, cardiovascular, and neurodegenerative disorders. This review aims to highlight some therapeutic strategies against metabolic syndrome involving integrative approaches to improve lifestyle and daily diet. The beneficial effects of foods containing antioxidant polyphenols, intestinal microbiota control, and physical activity were also considered. We comprehensively examined a large body of published articles involving basic, animal, and human studie, as well as recent guidelines. As a result, dietary polyphenols from natural plant-based antioxidants and adherence to the Mediterranean diet, along with physical exercise, are promising complementary therapies to delay or prevent the onset of metabolic syndrome and counteract diabesity and cardiovascular diseases, as well as to protect against neurodegenerative disorders and cognitive decline. Modulation of the intestinal microbiota reduces the risks associated with MS, improves diabetes and cardiovascular diseases (CVD), and exerts neuroprotective action. Despite several studies, the estimation of dietary polyphenol intake is inconclusive and requires further evidence. Lifestyle interventions involving physical activity and reduced calorie intake can improve metabolic outcomes.

Unlocking the healing power of psilocybin: an overview of the role of psilocybin therapy in major depressive disorder, obsessive-compulsive disorder and substance use disorder

Resistance to traditional treatment methods is still a major obstacle in modern psychiatry. As a result, several studies are currently being conducted to find effective alternatives to traditional therapies. One of these alternatives is psilocybin, a psychedelic substance that has been tested in clinical trials as an adjunct to psychotherapy. These studies focus on patients with major depressive disorder (MDD), obsessive-compulsive disorder (OCD) and substance use disorder (SUD), particularly alcohol and nicotine dependence. This article looks at the current understanding of psilocybin, including data from clinical trials conducted, psilocybin's mechanism of action, its safety and the level of risk associated with it.

The efficacy and safety of sertraline in maintenance hemodialysis patients with depression: A randomized controlled study

OBJECTIVE

To determine the efficacy and safety of sertraline in maintenance hemodialysis (MHD) patients with depression.

METHODS

A randomized controlled trial was conducted involving 125 MHD patients with depression. The treatment group received sertraline, while the control group did not receive any antidepressant treatment. After 12 weeks, we compared the changes in the Hamilton Depression Rating Scale (HAMD), the Medication Adherence Report Scale-5 (MARS-5), the Mini Nutritional Assessment short-form (MNA-SF), the Kidney Disease Quality of Life-36 (KDQOL-36) scores, selected clinical and laboratory indicators, and the incidence of drug-related adverse reactions between the two groups.

RESULTS

After 12 weeks of treatment, the HAMD scores of patients in the treatment group significantly decreased compared to before treatment and were lower than those in the control group. The KDQOL-36, MARS-5, and MNA-SF scores in the treatment group also significantly improved compared to before treatment and were superior to those in the control group. Albumin and hemoglobin levels in the treatment group significantly increased, while C-reactive protein significantly decreased. The incidence of nausea was slightly higher in the treatment group, and was mostly relieved after reducing the dosage of sertraline.

LIMITATIONS

This study is a single-center, small-sample study with a relatively short duration of treatment and follow-up.

CONCLUSIONS

Sertraline can alleviate depressive symptoms, and improve the quality of life and treatment compliance of MHD patients, while improving chronic inflammation, malnutrition, and anemia. However, starting with a low dose and reducing the maintenance dose is recommended when administering sertraline.

Immunotherapy for depression: Recent insights and future targets

Depression stands as a prominent contributor to global disability, entailing an elevated risk of suicide. Substantial evidence supports the notion that immune dysregulation may play a role in the development of depression and impede responses to antidepressant treatments. Immune dysregulation may cause depression in susceptible individuals through raising inflammatory responses. Differences in immune cell types and the release of pro-inflammatory mediators are observed in the blood and cerebrospinal fluid of patients with major depressive disorder, which is associated with neuroimmune dysfunction. Therefore, the interaction of peripheral and central immune targets in depression needs to be understood. Urgent attention is required for the development of innovative therapeutics directed at modulating immune responses for the treatment of depression. This review delineates the immune mechanisms involved in the pathogenesis of depression, assesses the therapeutic potential of immune system targeting for depression treatment, and deliberates on the merits and constraints of employing immunotherapy in the management of depression.

Chinese herbal medicines for the treatment of depression: a systematic review and network meta-analysis

Objectives: Amidst rising global burden of depression and the associated challenges with conventional antidepressant therapies, there is a growing interest in exploring the efficacy and safety of alternative treatments. This study uses a Bayesian network meta-analysis to rigorously evaluate the therapeutic potential of Chinese herbal medicines in the treatment of depression, focusing on their comparative efficacy and safety against standard pharmacological interventions. Methods: Five databases (PubMed, Wanfang Data, EMBASE, CNKI, and the Cochrane Library) and grey literature were searched from inception to end of July 2023 to identify studies that assessed the efficacy and safety of Chinese herbal medicines in treating depression. The response rate, Hamilton Depression Scale (HAMD) scores, and rates of adverse events were assessed through both direct and indirect comparisons. Data extraction and risk of bias assessment were meticulously performed. Statistical analysis used Markov chain Monte Carlo methods, with effect size estimates provided as odd ratios and their 95% confidence intervals. Results: A total of 198 RCTs involving 8,923 patients were analyzed, assessing 17 Chinese herbal medicines. Surface Under the Cumulative Ranking results indicated that the top three treatments with the best response rate were possibly Guipiwan, Ease Pill, and Chaihu Jia Longgu Muli Decoction; the top three treatments on the reduction of HAMD scores were Chai Hu Shu Gan San, Xingnao Jieyu Decoction, and Xiaoyao Powder; and the top three treatments with the lowest adverse effects rates were Xiaoyao Powder, Alprazolam, and Xingnao Jieyu Decoction. Interestingly, commonly used synthetic drugs such as Fluoxetine, Escitalopram, Amitriptyline, Sertraline, Flupentixol and Melitracen, and Venlafaxine, not only appeared to be less effective than specific Chinese herbal medicines (Gan Mai Da Zao Decoction, Chaihu Jia Longgu Muli Decoction, Chai Hu Shu Gan San, Danzhi-Xiaoyao-San, and Xingnao Jieyu Decoction), but they were also related to substantially higher risk of adverse events. Conclusion: Our findings elucidate the promising therapeutic potential of Chinese herbal medicines as viable alternatives in the treatment of depression, with certain herbs demonstrating enhanced efficacy and safety profiles. The outcomes of this study advocate for the integration of these alternative modalities into contemporary depression management paradigms. However, it underscores the necessity for larger, methodologically robust trials to further validate and refine these preliminary findings. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023452109.

Second Near-Infrared Macrophage-Biomimetic Nanoprobes for Photoacoustic Imaging of Neuroinflammation

Neuroinflammation is a significant pathological event involving the neurodegenerative process associated with many neurological disorders. Diagnosis and treatment of neuroinflammation in its early stage are essential for the prevention and management of neurological diseases. Herein, we designed macrophage membrane-coated photoacoustic (PA) probes (MSINPs), with targeting specificities based on naturally existing target-ligand interactions for the early diagnosis of neuroinflammation. The second near-infrared dye, IR1061, was doped into silica as the core and was encapsulated with a macrophage membrane. In vitro as well as in vivo, the MSINPs could target inflammatory cells via the inflammation chemotactic effect. PA imaging was used to trace the MSINPs in a neuroinflammation mouse model and showed a great targeted effect of MSINPs in the prefrontal cortex. Therefore, the biomimetic nanoprobe prepared in this study offers a new strategy for PA molecular imaging of neuroinflammation, which can enhance our understanding of the evolution of neuroinflammation in specific brain regions.

Physical Activity-Induced Modification of the Association of Long-Term Air Pollution Exposure with the Risk of Depression in Older Adults

PURPOSE

Evidence suggests that long-term air pollution exposures may induce depression; however, the influence of physical activity on this effect is unclear. We investigated modification of the associations between air pollution exposures and depression by the intensity of physical activity.

MATERIALS AND METHODS

This cross-sectional study included 1454 Korean adults. Depression was defined as a Geriatric Depression Scale score ≥8. Concentrations of particulate matter (PM10 and PM2.5: diameter ≤10 µm and ≤2.5 µm, respectively) and nitrogen dioxide (NO2) level at each participant's residential address were estimated. Based on metabolic equivalents, physical activity intensity was categorized as inactive, minimally active, or health-enhancing physical activity (HEPA).

RESULTS

Each 1-part per billion (ppb) NO2 concentration increase was significantly associated with a 6% [95% confidence interval (CI), 4%-8%] increase in depression risk. In older adults (≥65 years), a 1-ppb NO2 increase was associated (95% CI) with a 4% (1%-7%), 9% (5%-13%), and 21% (9%-33%) increase in depression risk in the inactive, minimally active, and HEPA groups, respectively. Compared with the inactive group, the minimally active (p=0.039) and HEPA groups (p=0.004) had higher NO2 exposure-associated depression risk. Associations of PM10 and PM2.5 with depression did not significantly differ by the intensity of physical activity.

CONCLUSION

We suggest that older adults who vigorously exercise outdoors may be susceptible to air pollution-related depression.

The potential of 5-methoxy-N,N-dimethyltryptamine in the treatment of alcohol use disorder: A first look at therapeutic mechanisms of action

Alcohol use disorder (AUD) remains one of the most prevalent psychiatric disorders worldwide with high economic costs. Current treatment options show modest efficacy and relapse rates are high. Furthermore, there are increases in the treatment gap and few new medications have been approved in the past 20 years. Recently, psychedelic-assisted therapy with psilocybin and lysergic acid diethylamide has garnered significant attention in the treatment of AUD. Yet, they require significant amounts of therapist input due to prolonged subjective effects (~4-12 h) leading to high costs and impeding implementation. Accordingly, there is an increasing interest in the rapid and short-acting psychedelic 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT). This paper offers a first look at potential therapeutic mechanisms for AUD by reviewing the current literature on 5-MeO-DMT. Primarily, 5-MeO-DMT is able to induce mystical experiences and ego-dissolution together with increases in psychological flexibility and mindfulness. This could decrease AUD symptoms through the alleviation of psychiatric mood-related comorbidities consistent with the negative reinforcement and self-medication paradigms. In addition, preliminary evidence indicates that 5-MeO-DMT modulates neural oscillations that might subserve ego-dissolution (increases in gamma), psychological flexibility and mindfulness (increases in theta), and the reorganization of executive control networks (increases in coherence across frequencies) that could improve emotion regulation and inhibition. Finally, animal studies show that 5-MeO-DMT is characterized by neuroplasticity, anti-inflammation, 5-HT2A receptor agonism, and downregulation of metabotropic glutamate receptor 5 with clinical implications for AUD and psychiatric mood-related comorbidities. The paper concludes with several recommendations for future research to establish the purported therapeutic mechanisms of action.

Targeting autophagy to counteract neuroinflammation: A novel antidepressant strategy

Depression is a common disease that affects physical and mental health and imposes a considerable burden on afflicted individuals and their families worldwide. Depression is associated with a high rate of disability and suicide. It causes a severe decline in productivity and quality of life. Unfortunately, the pathophysiological mechanisms underlying depression have not been fully elucidated, and the risk of its treatment is still presented. Studies have shown that the expression of autophagic markers in the brain and peripheral inflammatory mediators are dysregulated in depression. Autophagy-related genes regulate the level of autophagy and change the inflammatory response in depression. Depression is related to several aspects of immunity. The regulation of the immune system and inflammation by autophagy may lead to the development or deterioration of mental disorders. This review highlights the role of autophagy and neuroinflammation in the pathophysiology of depression, sumaries the autophagy-targeting small moleculars, and discusses a novel therapeutic strategy based on anti-inflammatory mechanisms that target autophagy to treat the disease.

CCR5 and inflammatory storm

Chemokines and their corresponding receptors play crucial roles in orchestrating inflammatory and immune responses, particularly in the context of pathological conditions disrupting the internal environment. Among these receptors, CCR5 has garnered considerable attention due to its significant involvement in the inflammatory cascade, serving as a pivotal mediator of neuroinflammation and other inflammatory pathways associated with various diseases. However, a notable gap persists in comprehending the intricate mechanisms governing the interplay between CCR5 and its ligands across diverse and intricate inflammatory pathologies. Further exploration is warranted, especially concerning the inflammatory cascade instigated by immune cell infiltration and the precise binding sites within signaling pathways. This study aims to illuminate the regulatory axes modulating signaling pathways in inflammatory cells by providing a comprehensive overview of the pathogenic processes associated with CCR5 and its ligands across various disorders. The primary focus lies on investigating the pathomechanisms associated with CCR5 in disorders related to neuroinflammation, alongside the potential impact of aging on these processes and therapeutic interventions. The discourse culminates in addressing current challenges and envisaging potential future applications, advocating for innovative research endeavors to advance our comprehension of this realm.

Unlocking the link between temporomandibular disorders and suicide ideation in pre-orthodontic patients: A moderated mediation model of depression and anxiety

BACKGROUND

Temporomandibular disorders (TMD) are a series of musculoskeletal diseases with high prevalence. A few studies have reported the correlation between TMD and suicide ideation (SI). However, the underlying mechanism of the relationship lacks in-depth exploration.

METHODS

A cross-sectional study was conducted among 954 pre-orthodontic patients. TMD assessment was based on the quintessential five TMD symptoms (5Ts) questionnaire. Anxiety, depression and pain catastrophizing was evaluated by Seven-item Generalized Anxiety Disorder Scale (GAD-7), Nine-item Patient Health Questionnaire (PHQ-9), and Pain Catastrophizing Scale (PCS), respectively. Correlational and moderated mediated analysis was preformed to demonstrate the relationship between TMD and SI.

RESULTS

In pre-orthodontic patients, 31.87 % reported having TMD symptoms and 6.50 % declared SI during the past two weeks. The SI prevalence was 10.53 % in participants with TMD and 4.62 % in those without TMD. Intra-articular TMD, rather than pain-related TMD were especially related with SI. Individuals with TMD had higher risk to SI (rs = 0.112, adjusted OR = 2.213, p < 0.001). The effect of TMD on SI was fully mediated through depression (β = 0.445, 95 % CI = [0.326, 0.563]). Anxiety exerted a negative moderating effect on the depression-SI relation (β = -0.033, 95 % CI = [-0.047, -0.019]).

LIMITATIONS

This study was a single-centered and cross-sectional survey. The data collection relied on self-reporting methods.

CONCLUSIONS

A positive link between TMD and SI was disclosed. The effect of TMD on SI was fully mediated through depression with anxiety as a negative moderator.

Transcutaneous electrical acupoint stimulation attenuated neuroinflammation and oxidative stress by activating SIRT1-induced signaling pathway in MCAO/R rat models

BACKGROUND

Silent information regulator 1 (SIRT1) plays a beneficial role in cerebral ischemic injury. Previous reports have demonstrated that transcutaneous electrical acupoint stimulation (TEAS) exerts a beneficial effect on ischemic stroke; however, whether SIRT1 participates in the underlying mechanism for the neuroprotective effects of TEAS against ischemic brain damage has not been confirmed.

METHODS

The rat models of middle cerebral artery occlusion/reperfusion (MCAO/R) were utilized in the current experiment. After MCAO/R surgery, rats in TEAS, EC and EX group received TEAS intervention with or without the injection of EX527, the SIRT1 inhibitor. Neurological deficit scores, infarct volume, hematoxylin eosin (HE) staining and apoptotic cell number were measured. The results of RNA sequencing were analyzed to determine the differential expression changes of genes among sham, MCAO and TEAS groups, in order to investigate the possible pathological processes involved in cerebral ischemia and explore the protective mechanisms of TEAS. Moreover, oxidative stress markers including MDA, SOD, GSH and GSH-Px were measured with assay kits. The levels of the proinflammatory cytokines, such as IL-6, IL-1β and TNF-α, were detected by ELISA assay, and Iba-1 (the microglia marker protein) positive cells was measured by immunofluorescence (IF). Western blot and IF were utilized to examine the levels of key molecules in SIRT1/FOXO3a and SIRT1/BRCC3/NLRP3 signaling pathways.

RESULTS

TEAS significantly decreased brain infarcted size and apoptotic neuronal number, and alleviated neurological deficit scores and morphological injury by activating SIRT1. The results of RNA-seq and bioinformatic analysis revealed that oxidative stress and inflammation were the key pathological mechanisms, and TEAS alleviated oxidative injury and inflammatory reactions following ischemic stroke. Then, further investigation indicated that TEAS notably attenuated neuronal apoptosis, neuroinflammation and oxidative stress damage in the hippocampus of rats with MCAO/R surgery. Moreover, TEAS intervention in the MCAO/R model significantly elevated the expressions of SIRT1, FOXO3a, CAT, BRCC3, NLRP3 in the hippocampus. Furthermore, EX527, as the inhibitor of SIRT1, obviously abolished the anti-oxidative stress and anti-neuroinflammatory roles of TEAS, as well as reversed the TEAS-mediated elevation of SIRT1, FOXO3a, CAT and reduction of BRCC3 and NLRP3 mediated by following MCAO/R surgery.

CONCLUSIONS

In summary, these findings clearly suggested that TEAS attenuated brain damage by suppressing apoptosis, oxidative stress and neuroinflammation through modulating SIRT1/FOXO3a and SIRT1/BRCC3/NLRP3 signaling pathways following ischemic stroke, which can be a promising treatment for stroke patients.

Cannabinoid type 2 receptors play a crucial role in social defeat-induced depression

BACKGROUND

The endocannabinoid system plays a crucial role in regulating mood, but the specific involvement of cannabinoid receptor type 2 (CB2R) in depression remains poorly understood. Similarly, the mechanisms by which electroacupuncture (EA) provides therapeutic benefits for depression are not clearly defined. This research aims to explore the function of CB2R in depression and examine if the therapeutic effects of EA are associated with the hippocampal CB2R system.

METHODS

Mice experiencing social defeat stress (SDS) were used to model depression and anxiety behaviors. We quantified hippocampal CB2R and N-arachidonoylethanolamide (AEA) levels. The efficacy of a CB2R agonist, JWH133, in mitigating SDS-induced behaviors was evaluated. Additionally, EA's impact on CB2R and AEA was assessed, along with the influence of CB2R antagonist AM630 on EA's antidepressant effects.

RESULTS

SDS led to depressive and anxiety-like behaviors, with corresponding decreases in hippocampal CB2R and AEA. Treatment with JWH133 ameliorated these behaviors. EA treatment resulted in increased CB2R and AEA levels, while AM630 blocked these antidepressant effects.

LIMITATIONS

The study mainly focused on the SDS model, which may not entirely reflect other depression models. Besides, further investigation is needed to understand the precise mechanisms by which CB2R and AEA contribute to EA's effects.

CONCLUSIONS

The study suggests hippocampal downregulation of CB2R and AEA contributes to depression. Upregulation of CB2R and AEA in response to EA suggests their involvement in EA's antidepressant effects. These findings provide insights into the role of the hippocampal CB2R system in depression and the potential mechanisms underlying EA's therapeutic effects.