Chronic administration of fluoxetine and pro-inflammatory cytokine change in a rat model of depression

Fluoxetine accelerates epileptogenesis and magnifies disease severity in a rat model of acquired epilepsy

OBJECTIVE

Many people with epilepsy experience comorbid anxiety and depression, and antidepressants remain a primary treatment for this. Emerging evidence suggests that these agents may modulate epileptogenesis to influence disease severity. Here, we assessed how treatment with the selective serotonin reuptake inhibitor (SSRI) antidepressant fluoxetine impacts epileptogenic, behavioral, and pathological sequelae following status epilepticus.

METHODS

Male Wistar rats received kainic acid to induce status epilepticus (SE) or vehicle (sham). Animals then received either fluoxetine (10 mg/kg/day) or vehicle for 8 weeks via subcutaneous osmotic pump. Video-electroencephalography was recorded continuously until behavioral testing at day 56, including assessments of anxiety- and depression-like behavior and spatial cognition. Postmortem immunocytochemistry studies examined mossy fiber sprouting.

RESULTS

Fluoxetine treatment significantly accelerated epileptogenesis following SE, reducing the average period to the first spontaneous seizure (from 32 days [vehicle] to 6 days [fluoxetine], p < .01). Also, fluoxetine exposure magnified the severity of the resultant epilepsy, increasing seizure frequency compared to vehicle (p < .01). Exposure to fluoxetine was associated with improved anxiety- and depression-like behaviors but significantly worsened cognition. Mossy fiber sprouting was more pronounced in fluoxetine-treated rats compared to vehicle (p < .0001).

SIGNIFICANCE

Our studies demonstrate that, using a model exhibiting spontaneous seizures, epileptogenesis is accelerated and magnified by fluoxetine, an effect that may be related to more severe pathological neuroplasticity. The differential influence of fluoxetine on behavior indicates that different circuitry and mechanisms are responsible for these comorbidities. These findings suggest that caution should be exercised when prescribing SSRI antidepressants to people at risk of developing epilepsy.

Effect of a high dose atorvastatin as added-on therapy on symptoms and serum AMPK/NLRP3 inflammasome and IL-6/STAT3 axes in patients with major depressive disorder: randomized controlled clinical study

Background

Neuroinflammation pathways have been associated with the development of major depressive disorders (MDD). The anti-inflammatory characteristics of statins have been demonstrated to have significance in the pathophysiology of depression.

Aim

To investigate the mechanistic pathways of high dose atorvastatin in MDD.

Patients and methods

This trial included 60 patients with MDD who met the eligibility requirements. Two groups of patients (n = 30) were recruited by selecting patients from the Psychiatry Department. Group 1 received 20 mg of fluoxetine plus a placebo once daily. Group 2 received fluoxetine and atorvastatin (80 mg) once daily. All patients were assessed by a psychiatrist using the Hamilton Depression Rating Scale (HDRS). A HDRS score of ≤7 indicates remission or partial remission [HDRS<17 and>7]. Response was defined as ≥ 50% drop in the HDRS score. The serum concentrations of nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP-3), interleukin-6 (IL-6), adenosine monophosphate activated protein kinase (AMPK), and signal transducer and activator of transcription factor-3 (STAT-3) were measured.

Results

The atorvastatin group showed a significant reduction in the levels of all measured markers along with a statistical increase in the levels of AMPK when compared to the fluoxetine group. The atorvastatin group displayed a significant decrease in HDRS when compared to its baseline and the fluoxetine group. The response rate and partial remission were higher in the atorvastatin group than fluoxetine (p = 0.03, and p = 0.005), respectively.

Conclusion

These results imply that atorvastatin at high doses may be a promising adjuvant therapy for MDD patients by altering the signaling pathways for AMPK/NLRP3 and IL-6/STAT-3.

Clinical Trial Registration

clinicaltrials.gov, identifier NCT05792540.

Current landscape of long COVID clinical trials

Long COVID was reported as a multi-systemic condition after the infection of SARS-CoV-2, and more than 65 million people are suffering from this disease. It has been noted that around 10% of severe SARS-CoV-2 infected individuals are suffering from the enduring effects of long COVID. The symptoms of long COVID have also been noted in several mild or asymptomatic SARS-CoV-2 infected individuals. While limited reports on clinical trials investigating new therapeutics for long COVID exist, there is an abundance of scattered information available regarding these trials. This review explores the extensive literature search, and complete clinical trial database search to map the current status of long COVID clinical trials worldwide. The study listed about 110 long COVID clinical trials. In addition to conducting extensive long COVID clinical trials, we have comprehensively presented an overview of the condition, its symptoms, notable manifestations, associated clinical trials, the unique challenges it poses, and our recommendations for addressing long COVID.

Assessing the Effects of Metabolic Disruption, Body Mass Index and Inflammation on Depressive Symptoms in Post-COVID-19 Condition: A Randomized Controlled Trial on Vortioxetine

INTRODUCTION

To date, there are no therapeutics that have gained regulatory approval by the United States Food and Drug Administration (FDA) for the treatment of post-COVID-19 condition (PCC), a debilitating condition characterized by cognitive impairment and mood symptoms. Additionally, persistent inflammation, metabolic dysfunction, and risks associated with an elevated body mass index (BMI) have been observed. Herein, we aimed to assess the efficacy of vortioxetine in improving depressive symptoms among individuals with PCC,  as modulated by inflammation, metabolic dysfunction, and BMI.

METHODS

In this post-hoc analysis, we present preliminary data obtained from an 8-week randomized, double-blind, placebo-controlled trial. Participants included  adults aged 18 years and older residing in Canada who were experiencing symptoms of World Health Organization (WHO)-defined PCC. Recruitment began November 2021 and ended January 2023. Of the 200 participants enrolled, 147 were randomized (1:1) to receive vortioxetine (5-20 mg, n = 73) or placebo (n = 74) for daily treatment under double-blind conditions. The primary outcome measure was the change from baseline to endpoint in the 16-Item Quick Inventory of Depressive Symptomatology Self-Report Questionnaire (QIDS-SR-16).

RESULTS

Our findings revealed significant effects for time (χ2 = 9.601, p = 0.002), treatment (χ2 = 9.135, p = 0.003), and the treatment × time × CRP × TG-HDL × BMI interaction (χ2 = 26.092, p < 0.001) on PCC-related depressive symptoms in the adjusted model. Moreover, the between-group analysis showed a significant improvement with vortioxetine at endpoint as compared to placebo (mean difference = - 5.41, SEM = 1.335, p < 0.001).

CONCLUSION

Overall, vortioxetine significantly improved depressive symptoms among participants with PCC in the adjusted model. Notably, individuals with baseline markers of increased inflammation, metabolic disruption, and elevated BMI exhibited a more pronounced antidepressant effect at endpoint.

TRIAL REGISTRATION NUMBER

NCT05047952 (ClinicalTrials.gov).

Cortical GABA Levels Are Reduced in Post-Acute COVID-19 Syndrome

After recovering from the acute COVID-19 illness, a substantial proportion of people continue experiencing post-acute sequelae of COVID-19 (PASC), also termed "long COVID". Their quality of life is adversely impacted by persistent cognitive dysfunction and affective distress, but the underlying neural mechanisms are poorly understood. The present study recruited a group of mostly young, previously healthy adults (24.4 ± 5.2 years of age) who experienced PASC for almost 6 months following a mild acute COVID-19 illness. Confirming prior evidence, they reported noticeable memory and attention deficits, brain fog, depression/anxiety, fatigue, and other symptoms potentially suggestive of excitation/inhibition imbalance. Proton magnetic resonance spectroscopy (1H-MRS) was used to examine the neurochemical aspects of cell signaling with an emphasis on GABA levels in the occipital cortex. The PASC participants were compared to a control (CNT) group matched in demographics, intelligence, and an array of other variables. Controlling for tissue composition, biological sex, and alcohol intake, the PASC group had lower GABA+/water than CNT, which correlated with depression and poor sleep quality. The mediation analysis revealed that the impact of PASC on depression was partly mediated by lower GABA+/water, indicative of cortical hyperexcitability as an underlying mechanism. In addition, N-acetylaspartate (NAA) tended to be lower in the PASC group, possibly suggesting compromised neuronal integrity. Persistent neuroinflammation may contribute to the pathogenesis of PASC-related neurocognitive dysfunction.

Fluoxetine combined with swimming exercise synergistically reduces lipopolysaccharide-induced depressive-like behavior by normalizing the HPA axis and brain inflammation in mice

Major depression disorder is a debilitating psychiatric disease affecting millions of people worldwide. This disorder is the leading cause of morbidity and mortality in high-income countries. Selective serotonin reuptake inhibitors such as fluoxetine are first-line drugs for treating depression-related disorders, but not all patients respond well to these antidepressants. This study aimed to evaluate whether fluoxetine combined with aerobic exercise can affect lipopolysaccharide (LPS)-induced depressive-like behavior, hypothalamic-pituitary-adrenal (HPA) axis dysregulation, and brain inflammation in mice. Male mice were exposed to fluoxetine, swimming exercise, or a combination of both and finally treated with LPS. We measured depression-related symptoms such as anhedonia, behavioral despair, weight gain, and food intake. Hormones (corticosterone and testosterone) and cytokines (IL-1β, IL-6, TNF-α, IL-10) were also measured in serum and brain (hippocampus and prefrontal cortex), respectively. The findings indicated that LPS induced anhedonia and behavioral despair and increased corticosterone, hippocampal IL-1β, TNF-α, and decreased testosterone and hippocampal IL-10 in mice. Fluoxetine and exercise separately reduced LPS-induced depressive-like behavior, while their combination synergistically reduced these symptoms in LPS-treated mice. We found fluoxetine alone increased food intake and body weight in LPS-treated mice. Fluoxetine and exercise combination reduced corticosterone, hippocampal TNF-α, and prefrontal IL-6 and TNF-α levels and increased testosterone and hippocampal and prefrontal IL-10 levels more effectively than fluoxetine alone in LPS-treated mice. This study suggests that swimming exercise combined with fluoxetine can affect depression-related behavior, HPA axis, and brain inflammation more effectively than when they are used separately.

The bidirectional association of nonalcoholic fatty liver disease with depression, bipolar disorder, and schizophrenia

Nonalcoholic fatty liver disease (NAFLD) is a complex metabolic-inflammatory disease associated with poor outcomes and decreased quality of life. NAFLD is overrepresented in patients with psychiatric disorders like depression, bipolar disorder, and schizophrenia; however, a comprehensive review on NAFLD and psychiatric disorders remains to be delineated. This review endeavors to investigate the association of NAFLD with psychiatric disorders, including shared pathogenesis and future clinical derivatives. Extant literature suggests that patients with psychiatric disorders (in particular, mood disorders) are more susceptible to the development of NAFLD due to multiple reasons, including but not limited to hypothalamic-pituitary-adrenal axis dysregulation, metabolic syndrome, and chronic perceived stress. Moreover, the clinical manifestations of mood disorders (e.g., anhedonia, psychomotor retardation, lifestyle modification, etc.), and potentially long-term treatment with weight-gaining agents, differentially affect these patients, making them more prone to NAFLD. Considering the increased morbidity associated with both mood disorders and NAFLD, our review recommends regular screenings for NAFLD in select patients with mood disorders exhibiting signs of increased risk (i.e., obesity, metabolic syndrome, diabetes, or family history of NAFLD) for better diagnosis and holistic care of both potentially interrelated conditions.

Differences and correlations of biochemical index levels in patients with bipolar disorder and major depressive disorder during a stable period

The differences and correlation of biochemical indexes between bipolar disorder (BPD) and major depressive disorder (MDD) in stable stage were analyzed and discussed. Patients diagnosed with BPD and MDD in the Third People's Hospital of Foshan from January 2019 to December 2021 were selected as the research subjects, with 200 cases in each. Fasting serum was collected from patients and then detected regarding TC, TG, high-density lipoprotein, low-density lipoprotein (LDL), aspartate aminotransferase, lactic dehydrogenase, creatine kinase, creatine kinase-MB, urea, creatinine, uric acid, alanine aminotransferase, glucose (GLU), hemoglobin A1c, prolactin, high-sensitivity C-reactive protein, homocysteine. The results showed that the mean age and serum LDL, GLU, and HbAc1 levels of the MDD group were significantly higher than those of the BPD group (P < .05), while there was no significant difference in other indexes (P > .05). The prevalence of BPD was significantly negatively correlated with patient age (r = -0.164, P = .020), LDL (r = -0.150, P = .034), GLU (r = -0.140, P = .048), and HbAc1 (r = -0.215, P = .002) (P < .05). There were no significant differences in serum Hcy and high-sensitivity C-reactive protein levels between the BPD and MDD groups. The age, fasting blood glucose, glycosylated hemoglobin, and LDL of BPD patients were negatively correlated with their incidence.

Antidepressant drug prescription and incidence of COVID-19 in mental health outpatients: a retrospective cohort study

BACKGROUND

Currently, the main pharmaceutical intervention for COVID-19 is vaccination. While antidepressant (AD) drugs have shown some efficacy in treatment of symptomatic COVID-19, their preventative potential remains largely unexplored. Analysis of association between prescription of ADs and COVID-19 incidence in the population would be beneficial for assessing the utility of ADs in COVID-19 prevention.

METHODS

Retrospective study of association between AD prescription and COVID-19 diagnosis was performed in a cohort of community-dwelling adult mental health outpatients during the 1st wave of COVID-19 pandemic in the UK. Clinical record interactive search (CRIS) was performed for mentions of ADs within 3 months preceding admission to inpatient care of the South London and Maudsley (SLaM) NHS Foundation Trust. Incidence of positive COVID-19 tests upon admission and during inpatient treatment was the primary outcome measure.

RESULTS

AD mention was associated with approximately 40% lower incidence of positive COVID-19 test results when adjusted for socioeconomic parameters and physical health. This association was also observed for prescription of ADs of the selective serotonin reuptake inhibitor (SSRI) class.

CONCLUSIONS

This preliminary study suggests that ADs, and SSRIs in particular, may be of benefit for preventing COVID-19 infection spread in the community. The key limitations of the study are its retrospective nature and the focus on a mental health patient cohort. A more definitive assessment of AD and SSRI preventative potential warrants prospective studies in the wider demographic.

Vagus nerve-dependent effects of fluoxetine on anxiety- and depression-like behaviors in mice

The vagus nerve is a major pathway in the body that is responsible for regulating the activity of the parasympathetic nervous system, which plays an important role in mood disorders including anxiety and depression. Fluoxetine, also known as Prozac, is widely used to treat depression. Nevertheless, there are few studies on the vagus nerve-mediated action of fluoxetine. In this study, we aimed to investigate the vagus nerve-dependent actions of fluoxetine in mice with restraint stress-induced or antibiotics-induced anxiety- and depression-like behaviors. Compared to sham operation, vagotomy alone did not exhibit significant effects on behavioral changes and serotonin-related biomarkers in mice not exposed to stress, antibiotics, or fluoxetine. Oral administration of fluoxetine significantly alleviated anxiety- and depression-like behaviors. However, celiac vagotomy significantly attenuated the anti-depressive effects of fluoxetine. The vagotomy also inhibited the effect of fluoxetine to attenuate restraint stress- or cefaclor-induced reduction in serotonin levels and Htr1a mRNA expression in the hippocampus. These findings suggest that the vagus nerve may regulate the efficacy of fluoxetine for depression.

A comparative study of the neuroprotective effects of dl-3-n-butylphthalide and edaravone dexborneol on cerebral ischemic stroke rats

INTRODUCTION

DL-3-n-butylphthalide (NBP) and edaravone dexborneol (Eda-Dex) are two promising reagents for stroke treatment. However, the impacts of NBP and Eda-Dex on poststroke mental deficits are still poorly understood. In this study, we aimed to investigate and compare the influences of NBP and Eda-Dex on neurological function and cognitive behavior in rats with ischemic stroke.

METHODS

An ischemic stroke model was established by middle cerebral artery occlusion (MCAO). After peritoneal administration of the drugs, the rats were subjected to neurological deficit evaluation, cerebral blood flow (CBF) assays, cerebral infarct area evaluations or behavioral tests. Brain tissues were collected and further analyzed by enzyme-linked immunosorbent assay (ELISA), western blotting or immunohistochemistry.

RESULTS

NBP and Eda-Dex significantly decreased the neurological score, reduced the cerebral infarct area and improved CBF. Behavioral changes as assessed in the sucrose preference test, novel object recognition test, and social interaction test were significantly alleviated by NBP and Eda-Dex in rats with ischemic stroke. Moreover, NBP and Eda-Dex significantly suppressed inflammation by targeting the nuclear factor kappa-B/inducible nitric oxide synthase (NF-κB/iNOS) pathway and significantly inhibited oxidative stress by targeting the kelch-1ike ECH-associated protein l/nuclear factor erythroid 2-related factor 2 (Keap1/Nrf2) pathway. In addition, NBP and Eda-Dex distinctly suppressed the activation of microglia and astrocytes and improved neuronal viability in the ischemic brain.

CONCLUSIONS

NBP and Eda-Dex improved neurological function and alleviated cognitive disorders in rats with ischemic stroke by synergistically inhibiting inflammation and oxidative stress.

DL-3-n-butylphthalide (NBP) alleviates poststroke cognitive impairment (PSCI) by suppressing neuroinflammation and oxidative stress

Currently, the recovery of cognitive function has become an essential part of stroke rehabilitation. DL-3-n-butylphthalide (NBP) is a neuroprotective reagent and has been used in stroke treatment. Clinical studies have confirmed that NBP can achieve better cognitive outcomes in ischemic stroke patients than in healthy controls. In this study, we aimed to investigate the influences of NBP on cognitive function in an ischemic reperfusion (I/R) rat model. Our results showed that NBP profoundly decreased neurological scores, reduced cerebral infarct areas and enhanced cerebral blood flow (CBF). NBP potently alleviated poststroke cognitive impairment (PSCI) including depression-like behavior and learning, memory and social cognition impairments, in I/R rats. NBP distinctly suppressed the activation of microglia and astrocytes and improved neuron viability in the ischemic brain. NBP inhibited the expression of inflammatory cytokines, including interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), by targeting the nuclear factor kappa B/inducible nitric oxide synthase (NF-κB/iNOS) pathway and decreased cerebral oxidative stress factors, including reactive oxygen species (ROS) and malondialdehyde (MDA), by targeting the kelch like ECH associated protein 1/nuclear factor-erythroid 2 p45-related factor 2 (Keap1/Nrf2) pathway in the ischemic brain. The current study revealed that NBP treatment improved neurological function and ameliorated cognitive impairment in I/R rats, possibly by synergistically suppressing inflammation and oxidative stress.

Untargeted and targeted mass spectrometry reveal the effects of theanine on the central and peripheral metabolomics of chronic unpredictable mild stress-induced depression in juvenile rats

l-theanine has been shown to have a therapeutic effect on depression. However, whether l-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well explained. Given the complexity of the pathogenesis of depression, this study investigated the preventive effect and mechanism of l-theanine on depression in juvenile rats by combining serum and hippocampal metabolomic strategies. Behavioral tests, hippocampal tissue sections, and serum and hippocampal biochemical indexes were studied, and the results confirmed the preventive effect of l-theanine. Untargeted reversed-phase liquid chromatography-quadrupole-time-of-flight mass spectrometry and targeted hydrophilic interaction liquid chromatography-triple quadrupole mass spectrometry were developed to analyze the metabolism changes in the serum and hippocampus to screen for potential biomarkers related to l-theanine treatment. The results suggested that 28 abnormal metabolites in the serum and hippocampus that were considered as potential biomarkers returned to near-normal levels after l-theanine administration. These biomarkers were involved in various metabolic pathways, mainly including amino acid metabolism and lipid metabolism. The levels of amino acids and neurotransmitters in the phenylalanine, tryptophan, and glutamic acid pathways were significantly reduced after l-theanine administration compared with chronic unpredictable mild stress-induced rats. In summary, l-theanine had a significant preventive effect on depression and achieved its preventive results on depression by regulating various aspects of the body, such as amino acids, lipids, and inflammation. This research systematically analyzed the mechanism of l-theanine in preventing depression and laid the foundation for applying l-theanine to prevent depression in children and adolescents.

Association between peripheral biomarkers and clinical response to IV ketamine for unipolar treatment-resistant depression: An open label study

BACKGROUND

Major Depression is the leading cause of disability worldwide. A cohort of patients do not respond adequately to available antidepressants, leading to treatment-resistant depression (TRD). We evaluated the antidepressant efficacy of an acute intravenous ketamine treatment (0.5 mg/kg) for patients with unipolar TRD, and measured peripheral blood-based biomarkers associated with response to treatment.

METHODS

Fifteen adults diagnosed with TRD completed an open label study of ten infusions of subanesthetic ketamine over four weeks. Out of fifteen patients, blood was collected from eleven patients at three timepoints to analyze peripheral biomarkers in isolated plasma, including IL-6, IL-10, TNF-α, BDNF, and irisin. Irisin analysis was completed using an ELISA assay, and the remaining biomarkers were analyzed together simultaneously using a multiplex immunoassay.

RESULTS

Repeated ketamine infusions produced a significant decrease in total average depressive symptoms (MADRS) at all timepoints. Improvements in depressive symptoms were significant at one week, and continued to significantly decrease until two weeks, where it was maintained. Ketamine was generally well tolerated, and we observed improvements in functional impairment, anhedonia, and psychiatric symptoms, with no increases in manic symptoms. Levels of BDNF throughout treatment inversely correlated to decreases in MADRS scores, and higher levels of baseline BDNF predicted mood responses at one- and four weeks.

LIMITATIONS

The study was observational and uncontrolled, with a sample size of 15. Outpatients remained on their course of medications, unless they were pharmacological agents that have previously been identified to block ketamine's effects.

CONCLUSIONS

Ketamine may be an efficacious and safe pharmacological option for the acute treatment of patients suffering from severe TRD. BDNF has the potential to function as a prognostic biomarker for predicting response to ketamine treatments.

Systematic metabolic characterization of mental disorders reveals age‐related metabolic disturbances as potential risk factors for depression in older adults

Mental disorders are associated with dysregulated metabolism, but comprehensive investigations of their metabolic similarities and differences and their clinical relevance are few. Here, based on the plasma metabolome and lipidome of subcohort1, comprising 100 healthy participants, 55 cases with anxiety, 52 persons with depression, and 41 individuals with comorbidity, which are from WCHAT, a perspective cohort study of community‐dwelling older adults aged over 50, multiple metabolites as potential risk factors of mental disorders were identified. Furthermore, participants with mental illnesses were classified into three subtypes (S1, S2, and S3) by unsupervised classification with lipidomic data. Among them, S1 showed higher triacylglycerol and lower sphingomyelin, while S2 displayed opposite features. The metabolic profile of S3 was like that of the normal group. Compared with S3, individuals in S1 and S2 had worse quality of life, and suffered more from sleep and cognitive disorders. Notably, an assessment of 6,467 individuals from the WCHAT showed an age‐related increase in the incidence of depression. Seventeen depression‐related metabolites were significantly correlated with age, which were validated in an independent subcohort2. Collectively, this work highlights the clinical relevance of metabolic perturbation in mental disorders, and age‐related metabolic disturbances may be a bridge‐linking aging and depressive.

Neuroprotective effects of aripiprazole in stress-induced depressive-like behavior: Possible role of CACNA1C

BACKGROUND

Depression is the most common psychiatric disorder. Recently, aripiprazole, a novel antipsychotic drug, has been approved as the adjunctive therapy for the Treatment-Resistant Depression (TRD). However, the mechanisms underlying the antidepressant effects of aripiprazole are not fully known. Besides the involvement of calcium signaling dysregulations in the pathophysiology of depression, there is some evidence of overexpressed CACNA1C (the gene encoding the Cav1.2 channels) following chronic stress in the brain regions, which involved in emotional and stress responses. Based on the data indicating the aripiprazole's effects on intracellular calcium levels, this study aimed to investigate the mechanisms of therapeutic effects of aripiprazole, by a focus on the modulation of CACNA1C expression, in the rat stress-induced model of depression.

METHODS

Using Chronic Unpredictable Mild Stress (CUMS) model of depression, we examined the effects of aripiprazole on depressive and anxiety-like behaviors (by forced swimming test and elevated plus maze), serum IL-6 (Elisa), and cell survival (Nissl staining). In addition, CACNA1C, BDNF, and TrkB expression in the PFC and hippocampus (RT-qPCR), as well as BDNF and GAP-43 protein levels in the hippocampus (Immunohistofluorescence), have been assayed.

RESULTS

Our data indicated that aripiprazole could improve anxiety and depressive-like behaviors, decrease the serum levels of IL-6 and hippocampal cell death following CUMS. In addition, we showed the significant modulation on overexpressed CACNA1C, as well as downregulated BDNF and GAP-43 expression DISCUSSION: These results demonstrate that aripiprazole may promote synaptic plasticity by improving the expression of BDNF and gap-43. In addition, inflammation reduction and CACNA1C expression downregulation may be some of mechanisms by which aripiprazole alleviates chronic stress-induced hippocampal cell death and play its pivotal antidepressant role.

LQFM212, a piperazine derivative, exhibits potential antioxidant effect as well as ameliorates LPS-induced behavioral, inflammatory and oxidative changes

AIMS

Oxidative stress, impaired antioxidant defense and neuroinflammation are often associated with the onset and progression of neuropsychiatric diseases. Conversely, several piperazine compounds presents beneficial neuropharmacological effects as well as antioxidant activity, and some derivatives combine both activities. LQFM212 (2,6-di-tert-butyl-4-((4-(2-hydroxyethyl)piperazin-1-yl)methyl)phenol) was synthesized to produce effects on CNS and to have an additional antioxidant effect. Previous preclinical tests have been shown anxiolytic- and antidepressant-like effects of LQFM212 in mice. Herein, the main objective was to verify the possible antioxidant potential and the effects of LQFM212 against behavioral changes, inflammatory and oxidative markers induced by lipopolysaccharide (LPS).

MAIN METHODS

Initially, antioxidant potential of LQFM212 was evaluated by electrochemical assays. Afterwards, the effects of oral treatment with LQFM212 were evaluated in mice using LPS-induced models of systemic or local inflammation.

KEY FINDINGS

In LPS-induced neuroinflammation, LQFM212 treatment reverted changes caused by LPS, demonstrated by attenuated anxiogenic- and depressive-like behaviors, reduced pro-inflammatory cytokines (TNF-α and IL-1β) and increased anti-inflammatory cytokines (IL-4 and IL-10) on serum, and also improved oxidative stress-related changes (levels of nitrite, malondialdehyde, glutathione and carbonylated protein, and superoxide dismutase, catalase, myeloperoxidase and cholinesterase activities) on brain cortex and hippocampus. However, LQFM212 treatment did not attenuate the inflammatory changes in LPS-induced pleurisy model.

SIGNIFICANCE

LQFM212 presents antioxidant activity and ameliorates behavioral, inflammatory and oxidative changes after LPS-induced neuroinflammation model. These effects do not seem to be secondary to a peripheral anti-inflammatory action of LQFM212, since this compound failed to attenuate the inflammatory changes in LPS-induced pleurisy model.

Stress- and drug-induced neuroimmune signaling as a therapeutic target for comorbid anxiety and substance use disorders

Stress and substance use disorders remain two of the most highly prevalent psychiatric conditions and are often comorbid. While individually these conditions have a debilitating impact on the patient and a high cost to society, the symptomology and treatment outcomes are further exacerbated when they occur together. As such, there are few effective treatment options for these patients, and recent investigation has sought to determine the neural processes underlying the co-occurrence of these disorders to identify novel treatment targets. One such mechanism that has been linked to stress- and addiction-related conditions is neuroimmune signaling. Increases in inflammatory factors across the brain have been heavily implicated in the etiology of these disorders, and this review seeks to determine the nature of this relationship. According to the "dual-hit" hypothesis, also referred to as neuroimmune priming, prior exposure to either stress or drugs of abuse can sensitize the neuroimmune system to be hyperresponsive when exposed to these insults in the future. This review completes an examination of the literature surrounding stress-induced increases in inflammation across clinical and preclinical studies along with a summarization of the evidence regarding drug-induced alterations in inflammatory factors. These changes in neuroimmune profiles are also discussed within the context of their impact on the neural circuitry responsible for stress responsiveness and addictive behaviors. Further, this review explores the connection between neuroimmune signaling and susceptibility to these conditions and highlights the anti-inflammatory pharmacotherapies that may be used for the treatment of stress and substance use disorders.

Depression, anxiety and stress among people infected with COVID-19 in Dhaka and Chittagong cities

Background

Covid-19 is an acute respiratory infectious disease caused by novel coronavirus 2019. Many individuals have suffered or are experiencing psychological symptoms due to feelings of isolation, insecurity and instability triggered by Covid-19. This study aimed to explore the perceived psychological distress and associated factors among people infected with Covid-19 in Dhaka and Chittagong cities.

Methods

Using the face-to-face interview method, a survey was conducted from 23 April to 22 May 2021 on a questionnaire on depression, anxiety and stress scale (DASS-21), socio-demographic, economic and health factors. Among those who had ever been infected with Covid-19, a total of 2092 respondents (1180 from Dhaka and 912 from Chittagong) were randomly selected and interviewed. χ2 test for independence of attributes was employed to observe the association of various socioeconomic, cultural, demographic and health factors with psychological distress. Moreover, multinomial logistic regression analysis was performed to explore the factors that contributed to psychological distress.

Results

Among participants from Dhaka, of three mental health conditions, the prevalence was higher for anxiety (80.0%), followed by stress (64.2%) and depression (59.8%), respectively. Anxiety was also more prevalent (57.3) among respondents in Chittagong, followed by depression (47.7%) and stress (39.5%). As the coexistence of symptoms, 52.8% of respondents in Dhaka, 34.4% in Chittagong experienced depression, anxiety and stress simultaneously. Moreover, in both Dhaka and Chittagong, all three psychological symptoms were strongly correlated in pairs. Multivariate analysis revealed that the most consistent factors associated with mild to moderate (MM), and severe to extremely severe (SES) depression were respondents from Chittagong who were illiterate or primary educated (OR = 0.166, CI: 0.076–0.364 for MM and OR = 0.041, CI: 0.013–0.131 for SES), male (OR = 0.999, CI: 0.666–1.496 for MM and OR = 0.395, CI: 0.249–0.625 for SES), single (OR = 0.393, CI: 0.157–0.982 for MM and OR = 0.121, CI: 0.049–0.303 for SES) and married (OR = 0.403, CI: 0.177–0.916 for MM and OR = 0.075, CI: 0.033–0.167 for SES), had a family of size ≤ 4 (OR = 0.253, CI: 0.140–0.458 for MM and OR = 0.114, CI: 0.059–0.218 for SES) and a family of size 5–6 (OR = 0.151, CI: 0.084–0.272), and no family members at risk being infected with Covid-19 (OR = 0.699, CI: 0.487–1.002 for MM and OR = 0.332, CI: 0.199–0.522 for SES). The analysis yielded similar findings for the other two mental health subscales, such as anxiety and stress. For respondents in Dhaka, the effect of factors other than sex on psychological distress was the opposite in Chittagong. Overall, psychological distress during the outbreak was greater among respondents in Dhaka than in Chittagong if respondents were not classified based on various characteristics.

Conclusion

This study showed that in both Dhaka and Chittagong, a substantially large portion of Covid-19-infected respondents experienced all three psychological distress (e.g., depression, anxiety and stress). Regardless of the dissimilarity between the results in Dhaka and Chittagong, better mental health support was needed for women in both cities.

Psychosocial factors associated with mental health and quality of life during the COVID-19 pandemic among low-income urban dwellers in Peninsular Malaysia

Background and aims

Mental well-being among low-income urban populations is arguably challenged more than any other population amid the COVID-19 pandemic. This study investigates factors associated with depression and anxiety symptoms and quality of life among Malaysia’s multi-ethnic urban lower-income communities.

Methods

This is a community-based house-to-house survey conducted from September to November 2020 at the Petaling district in Selangor, Malaysia. Five hundred and four households were identified using random sampling, and heads of eligible households were recruited. Inclusion criteria were age ≥18 years with a monthly household income ≤RM6960 (estimated $1600) without acute psychiatric illness. The PHQ-9, GAD-7 and EQ-5D were used for depression, anxiety, and quality of life, respectively. Multivariable logistic regression was performed for the final analysis.

Results

A total of 432 (85.7%) respondents with a mean age of 43.1 years completed the survey. Mild to severe depression was detected in 29.6%, mild to severe anxiety in 14.7%, and problematic quality of life in 27.8% of respondents. Factors associated with mild to severe depression were younger age, chronic health conditions, past stressful events, lack of communication gadgets and lack of assets or commercial property. While respiratory diseases, marital status, workplace issues, financial constraints, absence of investments, substance use and lack of rental income were associated with mild to severe anxiety. Attributing poverty to structural issues, help-seeking from professionals, and self-stigma were barriers, while resiliency facilitated good psychological health. Problematic quality of life was associated with depression, older age, unemployment, cash shortage, hypertension, diabetes, stressful life events and low health literacy.

Conclusions

A high proportion of the sampled urban poor population reported mild to severe anxiety and depression symptoms. The psychosocial determinants should inform policymakers and shape future work within this underserved population.

Fluoxetine improves bone microarchitecture and mechanical properties in rodents undergoing chronic mild stress - an animal model of depression

Depression is one of the most prevalent mental disorders associated with reductions in bone mineral density and increased fracture risk. Fluoxetine is a highly prescribed selective serotonin reuptake inhibitor (SSRI) in the treatment of depression and is reported to be a risk factor for fractures. The present study examined the effect of fluoxetine on bone microarchitecture and the mechanical properties under chronic mild stress (CMS), a rodent model of depression. Thirty-one 6-9 week-old rats were allocated to 4 groups: 1) CMS + fluoxetine group (n = 10), 2) fluoxetine-only group (n = 5), 3) CMS + placebo group (n = 10) and 4) control group (no CMS and treatment) (n = 6). After 16 weeks, bone microarchitecture of the distal femur was analyzed by µCT. Mechanical properties were assessed by the three-point bending test, and antidepressant efficacy was determined by sucrose preference and forced swimming tests. Significant correlations were found between volume of sucrose intake and bone volume/tissue volume (BV/TV) (p = 0.019) and elastic absorption energy (p = 0.001) in the fluoxetine only group. The fluoxetine-only group showed significantly higher in the second moment of area in y-direction (p = 0.0298), horizontal outer diameter (mm) (p = 0.0488) and average midshaft thickness (mm) (p = 0.00047) than control group. Comparing with the control group, there was a significant reduction in trabecular number (Tb.N) in the CMS + fluoxetine group (p = 0.026) but not the fluoxetine-only group (p > 0.05). Significant increases in trabecular separation were observed in the metaphysis of CMS + placebo (p = 0.003) and CMS + fluoxetine (p = 0.004) groups when compared to the control group but not in the fluoxetine-only group (p > 0.05). During the three-point bending test, the fluoxetine-only group demonstrated significantly higher structural strength than controls (p = 0.04). Micro computed tomography (µCT) slices showed loss of trabecular bone in the metaphysis region of the CMS + fluoxetine and CMS + placebo groups but not the fluoxetine-only and control groups. In an animal model of depression, the adverse effect on the bone microarchitecture was caused by CMS but not by fluoxetine. Without exposure to CMS, fluoxetine significantly increased the cross-sectional area, trabecular bone area, structural strength and osteoblasts / bone area as compared to control condition.

Anti-depressant effects of acupuncture: The insights from NLRP3 mediated pyroptosis and inflammation

The NLRP3-mediated pyroptosis, which could affect inflammation response, plays a key role in the development of depression. Acupuncture has been shown to be an effective treatment for depression. In this study, we aimed to determine whether acupuncture could confer antidepressant activity via decreasing NLRP3-mediated pyroptosis by reducing inflammation. Here, depression model of rats was induced by chronic unpredictable mild stress (CUMS) for 4 weeks. Acupuncture group was subjected to acupuncture at the Shangxing (GV23) and Fengfu (GV16) acupoints for 20 min every other day (a total of 14 times). Fluoxetine group was administered with fluoxetine (2.1 mg/kg with the concentration of 0.21 mg/mL) by oral gavage (1 mL/100 g) once a day for 28 days. Rats' depression-like phenotypes were reflected with behavioral tests and biological detection methods. Results showed that acupuncture significantly improved the depression-like behavior of CUMS rat, suppressed the expressions of NLRP3, ASC, caspase-1, GSDMD, IL-1β, IL-18, HMGB1, IFN-γ, IL-6 and TNF-α in the serum and hippocampus, restored the %area of microglia, astrocytes and neuronal cells in the hippocampus. These indicate that acupuncture can prevent CUMS-induced depression-like behaviors by reducing NLRP3-mediated pyroptosis and inflammation.

Brain-immune interaction mechanisms: Implications for cognitive dysfunction in psychiatric disorders

Objectives

Cognitive dysfunction has been identified as a major symptom of a series of psychiatric disorders. Multidisciplinary studies have shown that cognitive dysfunction is monitored by a two‐way interaction between the neural and immune systems. However, the specific mechanisms of cognitive dysfunction in immune response and brain immune remain unclear.

Materials and methods

In this review, we summarized the relevant research to uncover our comprehension of the brain–immune interaction mechanisms underlying cognitive decline.

Results

The pathophysiological mechanisms of brain‐immune interactions in psychiatric‐based cognitive dysfunction involve several specific immune molecules and their associated signaling pathways, impairments in neural and synaptic plasticity, and the potential neuro‐immunological mechanism of stress.

Conclusions

Therefore, this review may provide a better theoretical basis for integrative therapeutic considerations for psychiatric disorders associated with cognitive dysfunction.

Diverse polycyclic polyprenylated acylphloroglucinols with anti-neuroinflammatory activity from Hypericum beanii

A phytochemical investigation on the roots of Hypericum beanii resulted in the isolation of six new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperberlones A-F, along with fourteen known analogues. The structural characterization of these compounds was carried out by analyzing the HRESIMS data, 1D and 2D NMR spectroscopic data, electronic circular dichroism (ECD) calculations, and gauge-independent atomic orbital (GIAO) NMR calculations. Hyperberlone A (1) was a caged PPAP with a rare tricyclo[4.3.1.0^3,8]decane carbon skeleton. It was deduced to be biosynthetically generated from hyperbeanol C (8) through key Paternò-Büchi reaction, radical cascade cyclizations, and retro-aldol reaction. Compounds 4, 6, 7, 9, 14, and 16 exhibited significant nitric oxide (NO) production inhibitory effects in lipopolysaccharide (LPS)-induced BV-2 microglial cells with IC₅₀ values of 6.11-25.28 μM. Moreover, compound 4 significantly decreased the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in LPS-induced BV-2 microglia, as well as the phosphorylation of JNK.

A tale of two transmitters: serotonin and histamine as in vivo biomarkers of chronic stress in mice

Background

Stress-induced mental illnesses (mediated by neuroinflammation) pose one of the world’s most urgent public health challenges. A reliable in vivo chemical biomarker of stress would significantly improve the clinical communities’ diagnostic and therapeutic approaches to illnesses, such as depression.

Methods

Male and female C57BL/6J mice underwent a chronic stress paradigm. We paired innovative in vivo serotonin and histamine voltammetric measurement technologies, behavioral testing, and cutting-edge mathematical methods to correlate chemistry to stress and behavior.

Results

Inflammation-induced increases in hypothalamic histamine were co-measured with decreased in vivo extracellular hippocampal serotonin in mice that underwent a chronic stress paradigm, regardless of behavioral phenotype. In animals with depression phenotypes, correlations were found between serotonin and the extent of behavioral indices of depression. We created a high accuracy algorithm that could predict whether animals had been exposed to stress or not based solely on the serotonin measurement. We next developed a model of serotonin and histamine modulation, which predicted that stress-induced neuroinflammation increases histaminergic activity, serving to inhibit serotonin. Finally, we created a mathematical index of stress, S_i and predicted that during chronic stress, where S_i is high, simultaneously increasing serotonin and decreasing histamine is the most effective chemical strategy to restoring serotonin to pre-stress levels. When we pursued this idea pharmacologically, our experiments were nearly identical to the model’s predictions.

Conclusions

This work shines the light on two biomarkers of chronic stress, histamine and serotonin, and implies that both may be important in our future investigations of the pathology and treatment of inflammation-induced depression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-022-02508-9.

Omeprazole treatment manifests anxiolytic effects in a cysteamine hydrochloride induced mouse model of gastrointestinal disorder

Omeprazole, a proton pump inhibitor (PPI), has widely been used to treat various gastrointestinal (GI) disorders. Notably, many clinical symptoms of GI disorders have been known to be associated with anxiety. In recent years, an exponentially increased number of subjects with abnormal ageing, neurological deficits, and psychiatric problems simultaneously exhibit GI dysfunctions as well as anxiety. Considering the fact, drugs that are used to treat GI disorders can be speculated to mitigate anxiety-related symptoms, and vice versa. Although, omeprazole treatment has been reported to result in development of anxiety and neurocognitive decline, ample reports suggest that omeprazole treatment is beneficial for the positive regulation of neuroplasticity. While underlying mechanisms of omeprazole-mediated neurological alterations remain obscure, the available scientific data on the omeprazole induced adverse effects in the brain appear to be inadequate, uncertain, and controversial. Hence, this study revisited the effect of omeprazole treatment on the degree of anxiety-like behaviours in a cysteamine hydrochloride (HCl) induced mouse model of GI disorder using open field test (OFT), light-dark box (LDB) test and elevated plus maze (EPM). Results revealed that omeprazole treatment mitigates anxiety-related behaviours in the cysteamine HCl induced animal model of GI disorder. Thus, this study assuredly supports and validates the anxiolytic properties of omeprazole. However, the adverse effects associated with inappropriate intake of omeprazole may not completely be excluded. Therefore, this study advocates the future direction in determining the long-term effects of omeprazole on the brain functions.

Targeting the Adaptive Immune System in Depression: Focus on T Helper 17 Cells

There is a vital need to understand mechanisms contributing to susceptibility to depression to improve treatments for the 11% of Americans who currently suffer from this debilitating disease. The adaptive immune system, comprising T and B cells, has emerged as a potential contributor to depression, as demonstrated in the context of lymphopenic mice. Overall, patients with depression have reduced circulating T and regulatory B cells, "immunosuppressed" T cells, and alterations in the relative abundance of T cell subtypes. T helper (Th) cells have the capacity to differentiate to various lineages depending on the cytokine environment, antigen stimulation, and costimulation. Regulatory T cells are decreased, and the Th1/Th2 ratio and the Th17 cells are increased in patients with depression. Evidence for changes in each Th lineage has been reported to some extent in patients with depression. However, the evidence is strongest for the association of depression with changes in Th17 cells. Th17 cells produce the inflammatory cytokine interleukin (IL)-17A, and the discovery of Th17 cell involvement in depression evolved from the well established link that IL-6, which is required for Th17 cell differentiation, contributes to the onset, and possibly maintenance, of depression. One intriguing action of Th17 cells is their participation in the gut-brain axis to mediate stress responses. Although the mechanisms of action of Th17 cells in depression remain unclear, neutralization of IL-17A by anti-IL-17A antibodies, blocking stress-induced production, or release of gut Th17 cells represent feasible therapeutic approaches and might provide a new avenue to improve depression symptoms. SIGNIFICANCE STATEMENT: Th17 cells appear as a promising therapeutic target for depression, for which efficacious therapeutic options are limited. The use of neutralizing antibodies targeting Th17 cells has provided encouraging results in depressed patients with comorbid autoimmune diseases.

Registered clinical trials investigating treatment of long COVID: a scoping review and recommendations for research

Background

A considerable proportion of individuals report persistent, debilitating and disparate symptoms despite resolution of acute COVID-19 infection (i.e. long COVID). Numerous registered clinical trials investigating treatment of long COVID are expected to be completed in 2021–2022. The aim of this review is to provide a scope of the candidate treatments for long COVID. A synthesis of ongoing long COVID clinical trials can inform methodologic approaches for future studies and identify key research vistas.

Methods

Scoping searches were conducted on multiple national and international clinical trial registries. Interventional trials testing treatments for long COVID were selected. The search timeline was from database inception to 28 July 2021.

Results

This scoping review included 59 clinical trial registration records from 22 countries with a total projected enrolment of 6718. Considerable heterogeneity was exhibited amongst component records with respect to the characterization of long COVID (i.e. name, symptoms- including frequency, intensity, trajectory and duration- mode of ascertainment, and definition of acute phase). In addition, the majority of proposed interventions were non-pharmacological and either targeted multiple long COVID symptoms simultaneously, or focussed on treatment of respiratory/pulmonary sequelae. Multiple interventions targeted inflammation, as well as tissue oxygenation and cellular recovery, and several interventions were repurposed from analogous conditions.

Conclusions

The results of this scoping review investigating ongoing clinical trials testing candidate treatments for long COVID suggest that a greater degree of definitional stringency and homogeneity is needed insofar as the characterization of long COVID and inclusion/exclusion criteria.

Efficacy of escitalopram for poststroke depression: a systematic review and meta-analysis

Depression is very common after stroke, causing multiple sequelae. We aimed to explore the efficacy of escitalopram for poststroke depression (PSD). PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials, Clinical trials. gov, Wan fang Data (Chinese), VIP (Chinese) and CNKI (Chinese) were retrieved from inception to May 2021. We recruited Randomized Controlled Trials (RCTs) which met the inclusion criteria in our study. The depression rating scores, the incidence of PSD, adverse events as well as functional outcomes were analyzed. 11 studies and 1374 participants were recruited in our work. The results were depicted: the reduction of depression rating scores was significant in the escitalopram groups and the standard mean difference (SMD) was − 1.25 (P < 0.001), 95% confidence interval (95% CI), − 1.82 to − 0.68; the risk ratio (RR) of the incidence of PSD was 0.52 (95% CI, 0.29 to 0.91; P = 0.007 < 0.05), which was significantly lower in the escitalopram groups; Escitalopram is safe for stroke patients; there was improvement of the motor function. However, in sensitivity analyses, the conclusions of the motor function and the incidence of drowsiness were altered. The study suggests that escitalopram has a potentially effective role compared with control groups and demonstrates escitalopram is safe. However, the results of the motor function and the incidence of drowsiness should be considered carefully and remain to be discussed in the future.

Prevalence, Risk Factors and Intervention for Depression and Anxiety in Pulmonary Hypertension: A Systematic Review and Meta-analysis

Background

Current guidelines recommend psychological support for patients with pulmonary hypertension suffering from psychological adversity. However, little is known about the prevalence and risk factors of depression and anxiety in patients with pulmonary hypertension (PH).

Methods

Medline and Embase were searched from inception to 6 May 2021. Meta-analysis of proportions using the generalized linear mixed model was conducted to analyze the pooled prevalence rates of depression and anxiety in PH patients. Risk factors for depression and anxiety in PH patients were evaluated using meta regression.

Results

A total of 24 studies involving 2,161 PH patients were included. The pooled prevalence of depression in PH was 28.0% (95% CI: 20.5–36.8) and pooled prevalence of anxiety was 37.1% (95% CI: 28.7–46.4). There was a significantly higher prevalence of anxiety (p = 0.0013) amongst PH patients in Asia (61.1%) compared to Europe (40.3%) and North America (22.9%). In terms of risk factors, congenital heart disease-related pulmonary arterial hypertension (PAH-CHD) were significantly associated with both depression (OR: 1.68, 95% CI: 1.27–2.23, p = 0.024) and anxiety (OR: 1.63, 95% CI: 1.45–1.83, p = 0.002). On the other hand, chronic thromboembolic pulmonary hypertension (CTEPH, OR: 1.18, 95% CI: 1.10–1.26, p = 0.004) was significantly associated with depression, whereas worse pulmonary vascular resistance (β: 0.30, 95% CI: 0.09–0.52, p = 0.005) and cardiac index (β: −0.96, 95% CI: −1.58 to −0.35, p = 0.002) were significantly correlated with anxiety.

Conclusion

The prevalence of anxiety and depression in PH patients is alarmingly high, with an increased prevalence of anxiety in Asia compared to Europe or North America. Psychological support is warranted for patients with PH, particularly those with underlying congenital heart disease, CTEPH, and severe disease.

Systematic Review Registration

CRD42021251733.

Post-weaning Social Isolation in Male and Female Prairie Voles: Impacts on Central and Peripheral Immune System

The socially monogamous prairie vole (Microtus ochrogaster) offers a unique opportunity to examine the impacts of adolescent social isolation on the brain, immune system, and behavior. In the current study, male and female prairie voles were randomly assigned to be housed alone or with a same-sex cagemate after weaning (i.e., on postnatal day 21-22) for a 6-week period. Thereafter, subjects were tested for anxiety-like and depressive-like behaviors using the elevated plus maze (EPM) and Forced Swim Test (FST), respectively. Blood was collected to measure peripheral cytokine levels, and brain tissue was processed for microglial density in various brain regions, including the Nucleus Accumbens (NAcc), Medial Amygdala (MeA), Central Amygdala (CeA), Bed Nucleus of the Stria Terminalis (BNST), and Paraventricular Nucleus of the Hypothalamus (PVN). Sex differences were found in EPM and FST behaviors, where male voles had significantly lower total arm entries in the EPM as well as lower latency to immobility in the FST compared to females. A sex by treatment effect was found in peripheral IL-1β levels, where isolated males had a lower level of IL-1β compared to cohoused females. Post-weaning social isolation also altered microglial density in a brain region-specific manner. Isolated voles had higher microglial density in the NAcc, MeA, and CeA, but lower microglial density in the dorsal BNST. Cohoused male voles also had higher microglial density in the PVN compared to cohoused females. Taken together, these data suggest that post-weaning social housing environments can alter peripheral and central immune systems in prairie voles, highlighting a potential role for the immune system in shaping isolation-induced alterations to the brain and behavior.

SARS-CoV-2 Psychiatric Sequelae: A Review of Neuroendocrine Mechanisms and Therapeutic Strategies

From the earliest days of the coronavirus disease 2019 (COVID-19) pandemic, there have been reports of significant neurological and psychological symptoms following Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. This narrative review is designed to examine the potential psychoneuroendocrine pathogenic mechanisms by which SARS-CoV-2 elicits psychiatric sequelae as well as to posit potential pharmacologic strategies to address and reverse these pathologies. Following a brief overview of neurological and psychological sequelae from previous viral pandemics, we address mechanisms by which SARS-CoV-2 could enter or otherwise elicit changes in the CNS. We then examine the hypothesis that COVID-19-induced psychiatric disorders result from challenges to the neuroendocrine system, in particular the hypothalamic-pituitary-adrenal stress axis and monoamine synthesis, physiological mechanisms that are only further enhanced by the pandemic-induced social environment of fear, isolation, and socioeconomic pressure. Finally, we evaluate several FDA-approved therapeutics in the context of COVID-19-induced psychoneuroendocrine disorders.

Post-COVID-19 Depressive Symptoms: Epidemiology, Pathophysiology, and Pharmacological Treatment

The Coronavirus Disease 2019 (COVID-19) pandemic is still spreading worldwide over 2 years since its outbreak. The psychopathological implications in COVID-19 survivors such as depression, anxiety, and cognitive impairments are now recognized as primary symptoms of the "post-acute COVID-19 syndrome." Depressive psychopathology was reported in around 35% of patients at short, medium, and long-term follow-up after the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection. Post-COVID-19 depressive symptoms are known to increase fatigue and affect neurocognitive functioning, sleep, quality of life, and global functioning in COVID-19 survivors. The psychopathological mechanisms underlying post-COVID-19 depressive symptoms are mainly related to the inflammation triggered by the peripheral immune-inflammatory response to the viral infection and to the persistent psychological burden during and after infection. The large number of SARS-CoV-2-infected patients and the high prevalence of post-COVID-19 depressive symptoms may significantly increase the pool of people suffering from depressive disorders. Therefore, it is essential to screen, diagnose, treat, and monitor COVID-19 survivors' psychopathology to counteract the depression disease burden and related years of life lived with disability. This paper reviews the current literature in order to synthesize the available evidence regarding epidemiology, clinical features, neurobiological underpinning, and pharmacological treatment of post-COVID-19 depressive symptoms.

Onset and frequency of depression in post-COVID-19 syndrome: A systematic review

Following recovery from COVID-19, an increasing proportion of individuals have reported the persistence and/or new onset of symptoms which collectively have been identified as post-COVID-19 syndrome by the National Institute for Health and Care Excellence. Although depressive symptoms in the acute phase of COVID-19 have been well characterized, the frequency of depression following recovery of the acute phase remains unknown. Herein, we sought to determine the frequency of depressive symptoms and clinically-significant depression more than 12 weeks following SARS-CoV-2 infection. A systematic search of PubMed, Ovid Medline and Google Scholar for studies published between January 1, 2020 and June 5, 2021 was conducted. Frequency and factors associated with depression in post-COVID-19 syndrome were recorded and qualitatively assessed through narrative synthesis. Methodological quality and risk of bias was assessed using a modified version of the Newcastle-Ottawa Scale (NOS) for prospective cohort studies. Of 316 articles identified through our systematic search, eight studies were included. The frequency of depressive symptoms +12 weeks following SARS-CoV-2 infection ranged from 11 to 28%. The frequency of clinically-significant depression and/or severe depressive symptoms ranged from 3 to 12%. The severity of acute COVID-19 was not associated with the frequency of depressive symptoms. However, the component studies were highly heterogeneous with respect to mode of ascertainment, time of assessment, and location and age of patients. The majority of studies did not include an unexposed control group. Future research should endeavour to produce a standardized classification of post-COVID-19 syndrome, and as well as include unexposed control groups.

Key considerations in the pharmacological management of treatment-resistant depression

Introduction: Treatment-resistant depression (TRD) is a complex, multifactorial, and biologically heterogeneous disorder with debilitating outcomes. Understanding individual reasons why patients do not respond to treatment is necessary for improving clinical recommendations regarding medication regimens, augmentation strategies, and alternative treatments.Areas covered: This manuscript reviews evidence-based treatment strategies for the clinical management of TRD. Current developments in the field and potential future recommendations for personalized treatment of TRD are also discussed.Expert opinion: Treatment guidelines for TRD are limited by the heterogeneous nature of the disorder. Furthermore, current strategies reflect this heterogeneity by emphasizing disease characteristics as well as drug trial response or failure. Developing robust biomarkers that could one day be integrated into clinical practice has the potential to advance specific treatment targets and ultimately improve treatment and remission outcomes.

Enriched environment mitigates depressive behavior by changing the inflammatory activation phenotype of microglia in the hippocampus of depression model rats

BACKGROUND

Inflammation mediated by microglia has been shown to be involved in the pathogenesis of depression. The enriched environment (EE) can improve depression-like behaviors and reduce inflammatory reactions, but it is unclear whether this is by changing the inflammatory activation phenotype of microglia.

METHOD

A depression rat model was established using chronic unpredictable stress (CUS) for four weeks. The rats were then treated with EE or fluoxetine administration during the following three weeks. Behavior tests including sucrose preference, forced swimming and open field were applied to evaluate the depression-like behaviors of rats at the baseline period prior to CUS, the end of fourth week and at the end of the seventh week. Microglial activation and hippocampal neuro-inflammation were detected on postmortem using immunofluorescence, western blotting, and real-time polymerase reaction (PCR).

RESULT

The results showed that severe depressive-like behavior was induced by four weeks of CUS. Changes in peripheral blood inflammatory cytokines were detected by ELISA. Immunofluorescent staining showed the IBA-1 of microglia activation marker level significantly increased in affected rats. The hippocampal microglial activation state was determined by measuring the increased levels of iNOS an M1 marker and the decreased levels of CD206, an M2 marker. The activation of NF-κB upregulation of inflammatory cytokines in the hippocampus and factors such as IL-10 were decreased. This study showed that EE and chronic fluoxetine treatment alleviated the depressive-like behavior induced by chronic stress and significantly inhibited microglial activation, activated NF-κB inflammasome and increased pro-inflammatory cytokines.

CONCLUSION

EE can alleviate depression-like behavior by modulating the phenotype of microglia, inhibiting pro-inflammatory genes, and promoting anti-inflammatory genes. Furthermore, EE can effectively reduce the phosphorylation and expression levels of NF-κB.

Regulatory effect of vitamin D on pro-inflammatory cytokines and anti-oxidative enzymes dysregulations due to chronic mild stress in the rat hippocampus and prefrontal cortical area

BACKGROUND

Chronic stress increases the production of pro-inflammatory cytokines and oxidative stress in the brain, which underlay cognitive and psychological problems. In addition to the anti-depressants, vitamin D is known to act as an anti-inflammatory and anti-oxidative agent. This study investigates the specific effects of vitamin D in protecting hippocampus and pre-frontal cortex (PFC) against chronic mild stress (CMS)-induced activation of pro-inflammatory cytokines IL-6 and TNF-α and decreasing the activation of anti-oxidative enzymes super oxide dismutase (SOD) and glutathione peroxidase (GPx).

METHODS AND RESULTS

Rats were exposed to CMS for 3 weeks. Two groups of rats received vitamin D (5 and 10 μg/kg) and another received fluoxetine (5 mg/kg) along with CMS. Control groups were not exposed to CMS, but received treatments similar to CMS groups. Serum corticosterone and IL-6, TNF-α and SOD and GPx levels in the hippocampus and PFC were measured at the end of three weeks. CMS significantly increased corticosterone, IL-6, TNF-α and decreased SOD and GPx levels (P < 0.0001) in hippocampus and PFC. Vitamin D treatment reduced corticosterone levels (P < 0.01), increased SOD (P < 0.0001) and GPx (P < 0.01) and decreased IL-6 and TNF-α (P < 0.0001) levels in the hippocampus and PFC compared to rats treated with vitamin D vehicle. Vitamin D-10 regulation of SOD and IL-6 levels was more effective than fluoxetine (P < 0.0001 and P < 0.01, respectively, in hippocampus).

CONCLUSION

This study suggests that vitamin D effectively protects the key regions of the brain related to cognition and affective behavior, against the inflammation and oxidative stress caused by the chronic stress.

Rivaroxaban Modulates TLR4/Myd88/NF-Kβ Signaling Pathway in a Dose-Dependent Manner With Suppression of Oxidative Stress and Inflammation in an Experimental Model of Depression

Depression is a common mental illness leading to upset or anxiety, with a high incidence rate in the world. Depression can lead to suicidal thoughts and behavior. The present study aimed to evaluate the effect of the direct oral anticoagulant rivaroxaban (RVX), in the model of depression induced by chronic unpredicted mild stress (CUMS) in rats. Fifty-six male Wister rats were randomly divided into seven experimental groups (8 rats/group); Group 1: Control group given vehicle per oral (p.o.), Group 2: RVXL-control group (received rivaroxaban 20 mg/kg/day, p.o..), Group 3: RVXH-control group (received rivaroxaban 30 mg/kg/day, p.o.), Group 4: chronic unpredictable mild stress (CUMS) group, Group 5: FLX-treated CUMS group (received fluoxetine 10 mg/kg/day, p.o..), Group 6: RVXL-treated CUMS group (received rivaroxaban 20 mg/kg/day, p.o.), and Group 7: RVXH-treated CUMS group (received rivaroxaban 30 mg/kg/day, p.o.). The rats received the drugs from the first day of the experiment and continued till 4 weeks-the duration of the study. The following were measured: monoamine neurotransmitters, malondialdehyde (MDA), total nitrite/nitrate (NOx), reduced glutathione (GSH), superoxide dismutase (SOD), Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor-A (VEGF-A). A forced swimming test (FST) was done. Furthermore, histological changes and glial fibrillary acidic protein (GFAP) immunoexpression were evaluated. CUMS showed a significant decrease in hypothalamic neurotransmitters, hippocampal GSH, SOD, BNDF, and VEGF-A with a significant increase in hippocampal MDA, NOx, NF-kβ, Myd88, TLR4, TNF-α, and GFAP immunoexpression. RVX showed significant improvement in all parameters (p -value < 0.0001). In conclusion, RVX in a dose-dependent manner possesses potent ameliorative effects against depression by reducing the oxidative stress and inflammatory process, through the regulation of the TLR4/Myd88/NF-kβ signaling pathway.

Association Between Mood Disorders and Risk of COVID-19 Infection, Hospitalization, and Death: A Systematic Review and Meta-analysis

IMPORTANCE

Preexisting noncommunicable diseases (eg, diabetes) increase the risk of COVID-19 infection, hospitalization, and death. Mood disorders are associated with impaired immune function and social determinants that increase the risk of COVID-19. Determining whether preexisting mood disorders represent a risk of COVID-19 would inform public health priorities.

OBJECTIVE

To assess whether preexisting mood disorders are associated with a higher risk of COVID-19 susceptibility, hospitalization, severe complications, and death.

DATA SOURCES

Systematic searches were conducted for studies reporting data on COVID-19 outcomes in populations with and without mood disorders on PubMed/MEDLINE, The Cochrane Library, PsycInfo, Embase, Web of Science, Google/Google Scholar, LitCovid, and select reference lists. The search timeline was from database inception to February 1, 2021.

STUDY SELECTION

Primary research articles that reported quantitative COVID-19 outcome data in persons with mood disorders vs persons without mood disorders of any age, sex, and nationality were selected. Of 1950 articles identified through this search strategy, 21 studies were included in the analysis.

DATA EXTRACTION AND SYNTHESIS

The modified Newcastle-Ottawa Scale was used to assess methodological quality and risk of bias of component studies. Reported adjusted odds ratios (ORs) were pooled with unadjusted ORs calculated from summary data to generate 4 random-effects summary ORs, each corresponding to a primary outcome.

MAIN OUTCOMES AND MEASURES

The 4 a priori primary outcomes were COVID-19 susceptibility, COVID-19 hospitalization, COVID-19 severe events, and COVID-19 death. The hypothesis was formulated before study search. Outcome measures between individuals with and without mood disorders were compared.

RESULTS

This review included 21 studies that involved more than 91 million individuals. Significantly higher odds of COVID-19 hospitalization (OR, 1.31; 95% CI, 1.12-1.53; P = .001; n = 26 554 397) and death (OR, 1.51; 95% CI, 1.34-1.69; P < .001; n = 25 808 660) were found in persons with preexisting mood disorders compared with those without mood disorders. There was no association between mood disorders and COVID-19 susceptibility (OR, 1.27; 95% CI, 0.73-2.19; n = 65 514 469) or severe events (OR, 0.94; 95% CI, 0.87-1.03; n = 83 240). Visual inspection of the composite funnel plot for asymmetry indicated the presence of publication bias; however, the Egger regression intercept test result was not statistically significant.

CONCLUSIONS AND RELEVANCE

The results of this systematic review and meta-analysis examining the association between preexisting mood disorders and COVID-19 outcomes suggest that individuals with preexisting mood disorders are at higher risk of COVID-19 hospitalization and death and should be categorized as an at-risk group on the basis of a preexisting condition.

Fluoxetine hydrochloride loaded lipid polymer hybrid nanoparticles showed possible efficiency against SARS-CoV-2 infection

Up to date, there were no approved drugs against coronavirus (COVID-19) disease that dangerously affects global health and the economy. Repurposing the existing drugs would be a promising approach for COVID-19 management. The antidepressant drugs, selective serotonin reuptake inhibitors (SSRIs) class, have antiviral, anti-inflammatory, and anticoagulant effects, which makes them auspicious drugs for COVID 19 treatment. Therefore, this study aimed to predict the possible therapeutic activity of SSRIs against COVID-19. Firstly, molecular docking studies were performed to hypothesize the possible interaction of SSRIs to the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-COV-2) main protease. Secondly, the candidate drug was loaded in lipid polymer hybrid (LPH) nanoparticles to enhance its activity. The studied SSRIs were Fluoxetine hydrochloride (FH), Atomoxteine, Paroxetine, Nisoxteine, Repoxteine RR, and Repoxteine SS. Interestingly, FH could effectively bind with SARS-COV-2 main protease via hydrogen bond formation with low binding energy (-6.7 kcal/mol). Moreover, the optimization of FH-LPH formulation achieved 65.1 ± 2.7% encapsulation efficiency, 10.3 ± 0.4% loading efficiency, 98.5 ± 3.5 nm particle size, and −10.5 ± 0.45 mV zeta potential. Additionally, it improved cellular internalization in a time-dependent manner with good biocompatibility on Human lung fibroblast (CCD-19Lu) cells. Therefore, the study suggested the potential activity of FH-LPH nanoparticles against the COVID-19 pandemic.

Effects of Geniposide and Geniposidic Acid on Fluoxetine-Induced Muscle Atrophy in C2C12 Cells

Fluoxetine, an antidepressant known as a selective 5-hydroxytryptamine reuptake inhibitor (SSRI), can cause side effects such as muscle atrophy with long-term use, but the mechanism is not fully understood. Geniposide (GPS) and geniposidic acid (GPSA), the main components of Gardenia jasminoides fruit, have been shown to have biological activity in disease prevention, but their role in preventing FXT-related side effects such as muscle atrophy remains unclear. The process of muscle atrophy is a complex physiological mechanism involving the balance of protein synthesis and catabolism. In this study, we hypothesized that FXT may suppress hypertrophy signaling and activate the atrophy mechanisms, resulting in proteolysis and reduced protein synthesis, while geniposide (GPS) and geniposide acid (GPSA) may be beneficial in improving muscle weakness caused by FXT. The C2C12 cell model was used to examine the expression of hypertrophy signaling (PI3K, Akt, and mTOR) and protein break signals (FOXO, MuRF-1, and MyHC). Our data indicated that FXT inhibited MyHC and promoted MuRF-1 protein expression by downregulating the signaling pathways of p-ERK1/2, p-Akt, p-mTOR, and p-FOXO, resulting in a decrease in differentiation and myotube formation in C2C12 muscle cells, which further resulted in muscle atrophy. However, GPS and GPSA can positively regulate the atrophy mechanism induced by FXT in muscle cells, thereby ameliorating the imbalance in muscle synthesis. In conclusion, GPS and GPSA have the potential to attenuate the muscle loss caused by long-term FXT administration, diseases, or the aging process.

Epicatechin treatment generates resilience to chronic mild stress-induced depression in a murine model

Several studies have proposed that cocoa products-enriched in flavonoids reduce anxiety and depressive symptoms. (-)-Epicatechin (Epi), a flavonoid present in high concentration in cocoa, has been associated with many dark chocolate effects and has been postulated as an exercise mimetic. Physical exercise is used as an adjuvant treatment for many depressive patients. This study aimed to evaluate the impact of Epi on resilience in depression-like behavior in a murine model. Male mice were randomly selected and divided into four groups (n = 8/group). Beginning at the age of 8-9 weeks, the mice were subjected to Chronic Mild Stress (CMS) and/or treatment Epi for five weeks. Epi was administered by oral gavage twice daily/5 weeks. The control group was housed in conditions without stress and Epi treatment. Depressive behavior was evaluated by sucrose preference and open field tests. Interestingly, Epi reduced anhedonia and anxiogenic behavior in the murine stress model. These results suggest that Epi induces resilience to stress-induced depression. Furthermore, our findings propose that muscles respond to Epi treatment according to their type of metabolism and that kynurenine aminotransferases (KATs) could play a role in modulating this response.

Glycogen Synthase Kinase-3: A Focal Point for Advancing Pathogenic Inflammation in Depression

Increasing evidence indicates that the host immune response has a monumental role in the etiology of major depressive disorder (MDD), motivating the development of the inflammatory hypothesis of depression. Central to the involvement of chronic inflammation in MDD is a wide range of signaling deficits induced by the excessive secretion of pro-inflammatory cytokines and imbalanced T cell differentiation. Such signaling deficits include the glutamatergic, cholinergic, insulin, and neurotrophin systems, which work in concert to initiate and advance the neuropathology. Fundamental to the communication between such systems is the protein kinase glycogen synthase kinase-3 (GSK-3), a multifaceted protein critically linked to the etiology of MDD and an emerging target to treat pathogenic inflammation. Here, a consolidated overview of the widespread multi-system involvement of GSK-3 in contributing to the neuropathology of MDD will be discussed, with the feed-forward mechanistic links between all major neuronal signaling pathways highlighted.

Defining Valid Chronic Stress Models for Depression With Female Rodents

Women are twice as likely to experience depression than men, yet until recently, preclinical studies in rodents have focused almost exclusively on males. As interest in sex differences and sex-specific mechanisms of stress susceptibility increases, chronic stress models for inducing depression-relevant behavioral and physiological changes in male rodents are being applied to females, and several new models have emerged to include both males and females, yet not all models have been systematically validated in females. An increasing number of researchers seek to include female rodents in their experimental designs, asking the question "what is the ideal chronic stress model for depression in females?" We review criteria for assessing female model validity in light of key research questions and the fundamental distinction between studying sex differences and studying both sexes. In overviewing current models, we explore challenges inherent to establishing an ideal female chronic stress model, with particular emphasis on the need for standardization and adoption of validated behavioral tests sensitive to stress effects in females. Taken together, these considerations will empower female chronic stress models to provide a better understanding of stress susceptibility and allow the development of efficient sex-specific treatments.

How Stress Shapes Neuroimmune Function: Implications for the Neurobiology of Psychiatric Disorders

Chronic stress causes physiological and hormonal adaptations that lead to neurobiological consequences and behavioral and cognitive impairments. In particular, chronic stress has been shown to drive reduced neurogenesis and altered synaptic plasticity in brain regions that regulate mood and motivation. The neurobiological and behavioral effects of stress resemble the pathophysiology and symptoms observed in psychiatric disorders, suggesting that there are similar underlying mechanisms. Accumulating evidence indicates that neuroimmune systems, particularly microglia, have a critical role in regulating the neurobiology of stress. Preclinical models indicate that chronic stress provokes changes in microglia phenotype and increases inflammatory cytokine signaling, which affects neuronal function and leads to synaptic plasticity deficits and impaired neurogenesis. More recent work has shown that microglia can also phagocytose neuronal elements and contribute to structural remodeling of neurons in response to chronic stress. In this review we highlight work by the Duman research group (as well as others) that has revealed how chronic stress shapes neuroimmune function and, in turn, how inflammatory mediators and microglia contribute to the neurobiological effects of chronic stress. We also provide considerations to engage the therapeutic potential of neuroimmune systems, with the goal of improving treatment for psychiatric disorders.

Integrating the monoamine and cytokine hypotheses of depression: Is histamine the missing link?

Psychiatric diseases, like depression, largely affect the central nervous system (CNS). While the underlying neuropathology of depressive illness remains to be elucidated, several hypotheses have been proposed as molecular underpinnings for major depressive disorder, including the monoamine hypothesis and the cytokine hypothesis. The monoamine hypothesis has been largely supported by the pharmaceuticals that target monoamine neurotransmitters as a treatment for depression. However, these antidepressants have come under scrutiny due to their limited clinical efficacy, side effects, and delayed onset of action. The more recent, cytokine hypothesis of depression is supported by the ability of immune-active agents to induce "sickness behaviour" akin to that seen with depression. However, treatments that more selectively target inflammation have yielded inconsistent antidepressive results. As such, neither of these hypotheses can fully explain depressive illness pathology, implying that the underlying neuropathological mechanisms may encompass aspects of both theories. The goal of the current review is to integrate these two well-studied hypotheses and to propose a role for histamine as a potential unifying factor that links monoamines to cytokines. Additionally, we will focus on stress-induced depression, to provide an updated perspective of depressive illness research and thereby identify new potential targets for the treatment of major depressive disorder.

SSRIs: Applications in inflammatory lung disease and implications for COVID-19

Selective serotonin reuptake inhibitors (SSRIs) have anti-inflammatory properties that may have clinical utility in treating severe pulmonary manifestations of COVID-19. SSRIs exert anti-inflammatory effects at three mechanistic levels: (a) inhibition of proinflammatory transcription factor activity, including NF-κB and STAT3; (b) downregulation of lung tissue damage and proinflammatory cell recruitment via inhibition of cytokines, including IL-6, IL-8, TNF-α, and IL-1β; and (c) direct suppression inflammatory cells, including T cells, macrophages, and platelets. These pathways are implicated in the pathogenesis of COVID-19. In this review, we will compare the pathogenesis of lung inflammation in pulmonary diseases including COVID-19, ARDS, and chronic obstructive pulmonary disease (COPD), describe the anti-inflammatory properties of SSRIs, and discuss the applications of SSRIS in treating COVID-19-associated inflammatory lung disease.