Neurobiology and Therapeutic Potential of Cyclooxygenase-2 (COX-2) Inhibitors for Inflammation in Neuropsychiatric Disorders

Network-based drug repurposing for schizophrenia

Despite recent progress, the challenges in drug discovery for schizophrenia persist. However, computational drug repurposing has gained popularity as it leverages the wealth of expanding biomedical databases. Network analyses provide a comprehensive understanding of transcription factor (TF) regulatory effects through gene regulatory networks, which capture the interactions between TFs and target genes by integrating various lines of evidence. Using the PANDA algorithm, we examined the topological variances in TF-gene regulatory networks between individuals with schizophrenia and healthy controls. This algorithm incorporates binding motifs, protein interactions, and gene co-expression data. To identify these differences, we subtracted the edge weights of the healthy control network from those of the schizophrenia network. The resulting differential network was then analysed using the CLUEreg tool in the GRAND database. This tool employs differential network signatures to identify drugs that potentially target the gene signature associated with the disease. Our analysis utilised a large RNA-seq dataset comprising 532 post-mortem brain samples from the CommonMind project. We constructed co-expression gene regulatory networks for both schizophrenia cases and healthy control subjects, incorporating 15,831 genes and 413 overlapping TFs. Through drug repurposing, we identified 18 promising candidates for repurposing as potential treatments for schizophrenia. The analysis of TF-gene regulatory networks revealed that the TFs in schizophrenia predominantly regulate pathways associated with energy metabolism, immune response, cell adhesion, and thyroid hormone signalling. These pathways represent significant targets for therapeutic intervention. The identified drug repurposing candidates likely act through TF-targeted pathways. These promising candidates, particularly those with preclinical evidence such as rimonabant and kaempferol, warrant further investigation into their potential mechanisms of action and efficacy in alleviating the symptoms of schizophrenia.

Apigetrin ameliorates doxorubicin prompted testicular damage: biochemical, spermatological and histological based study

Doxorubicin (DOX) is a highly effective, commonly prescribed, potent anti-neoplastic drug that damages the testicular tissues and leads to infertility. Apigetrin (APG) is an important flavonoid that shows diverse biological activities. The present research was designed to evaluate the alleviative role of APG against DOX-induced testicular damages in rats. Forty-eight adult male albino rats were randomly distributed into 4 groups, control, DOX administered (3 mgkg-1), DOX + APG co-administered (3 mgkg-1 of DOX; 15 mgkg-1 of APG), and APG administered group (15 mgkg-1). Results of the current study indicated that DOX treatment significantly reduced the activities of superoxide dismutase (SOD), glutathione reductase (GSR), catalase (CAT) and glutathione peroxidase (GPx), while increasing the levels of malondialdehyde (MDA) and reactive oxygen species (ROS). DOX treatment also reduced the sperm count, viability, and motility. Moreover, DOX significantly increased the sperm morphological anomalies and reduced the levels of plasma testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The administration of DOX significantly increased the expressions of Bax and Caspase-3, as well as the levels of inflammatory markers. Additionally, DOX treatment significantly downregulated the expressions of steroidogenic enzymes (StAR, 3β-HSD and 17β-HSD) and Bcl-2. Furthermore, DOX administration provoked significant histopathological abnormalities in the testicular tissues. However, APG supplementation significantly reversed all the testicular damages due to its androgenic, anti-apoptotic, anti-oxidant and anti-inflammatory nature. Therefore, it is concluded that APG may prove a promising therapeutic agent to treat DOX-induced testicular damages.

Targeting inflammatory pathways for treatment of the major depressive disorder

Current treatments modalities for major depressive disorder (MDD) mainly target the monoaminergic neurotransmission. However, the therapeutic inadequacy and adverse effects confine the use of these conventional antidepressants to a limited subset of MDD patients. The classical antidepressants are increasingly proving unsatisfactory in tackling the treatment-resistant depression (TRD). Hence, the focus of treatment is shifting to alternative pathogenic pathways involved in depression. Preclinical and clinical evidences accumulated across the last decades have unequivocally affirmed the causative role of immuno-inflammatory pathways in the progression of depression. There is an upsurge in the clinical evaluations of the drugs having anti-inflammatory effects as antidepressants. This review highlights the molecular mechanisms connecting the inflammatory pathways to the MDD and current clinical status of inflammation modulating drugs in the treatment of MDD.

Celecoxib for Mood Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The effects of celecoxib on a broad spectrum of mood disorders and on inflammatory parameters have not yet been comprehensively evaluated. The aim of this study was to systematically summarize the available knowledge on this topic. Data from both preclinical and clinical studies were analyzed, considering the efficacy and safety of celecoxib in the treatment of mood disorders, as well as the correlation of inflammatory parameters with the effect of celecoxib treatment. Forty-four studies were included. We found evidence supporting the antidepressant efficacy of celecoxib in a dose of 400 mg/day used for 6 weeks as an add-on treatment in major depression (SMD = -1.12 [95%Cl: -1.71,-0.52], p = 0.0002) and mania (SMD = -0.82 [95% CI:-1.62,-0.01], p = 0.05). The antidepressant efficacy of celecoxib in the above dosage used as sole treatment was also confirmed in depressed patients with somatic comorbidity (SMD = -1.35 [95% CI:-1.95,-0.75], p < 0.0001). We found no conclusive evidence for the effectiveness of celecoxib in bipolar depression. Celecoxib at a dose of 400 mg/d used for up to 12 weeks appeared to be a safe treatment in patients with mood disorders. Although an association between celecoxib response and inflammatory parameters has been found in preclinical studies, this has not been confirmed in clinical trials. Further studies are needed to evaluate the efficacy of celecoxib in bipolar depression, as well as long-term studies evaluating the safety and efficacy of celecoxib in recurrent mood disorders, studies involving treatment-resistant populations, and assessing the association of celecoxib treatment with inflammatory markers.

Effect of selective cyclooxygenase inhibitors on animal behaviour and monoaminergic systems of the rat brain

The long-term effects of cyclooxygenase 1 and 2 (COX-1/2) inhibitors are usually tested in terms of the periphery of the organism. Therefore, we studied the effects of SC560 (selective COX-1 inhibitor) and celecoxib (selective COX-2 inhibitor) on the activity of brain monoaminergic systems and animal behaviour. Additionally, we tested the effect of these inhibitors during inflammation. We have observed that long-term administration of celecoxib reduces the activity of the noradrenergic system, increases the activity of dopaminergic and serotonergic systems, increases locomotor activity, and enhances the exploratory behaviour of rats. Administration of SC560 also increases the activity of dopaminergic and serotonergic systems but reduces locomotor activity and impairs the exploratory behaviour of rats. The mechanism responsible for decreased activity of the noradrenergic system may be related to the weakening of activity of the positive feedback loop between the paraventricular nucleus and coeruleus locus. We suggest that the effect of used inhibitors on the dopaminergic system is associated with a possible increase in anandamide concentration and its effect on dopamine reuptake in synaptic clefts. It also appears that cyclooxygenase peroxidase activity may play a role in this process. In turn, changes in the activity of the serotonergic system may be related to the activity of indoleamine-2,3-dioxygenase, which decreases because of the decreased concentration of pro-inflammatory compounds. We believe that behavioural changes induced by COX inhibitors are the result of the modified activity of monoaminergic CNS systems in the brainstem, hypothalamus, and medial prefrontal cortex.

Biological hypotheses, risk factors, and biomarkers of schizophrenia

Both the discovery of biomarkers of schizophrenia and the verification of biological hypotheses of schizophrenia are an essential part of the process of understanding the etiology of this mental disorder. Schizophrenia has long been considered a neurodevelopmental disease whose symptoms are caused by impaired synaptic signal transduction and brain neuroplasticity. Both the onset and chronic course of schizophrenia are associated with risk factors-induced disruption of brain function and the establishment of a new homeostatic setpoint characterized by biomarkers. Different risk factors and biomarkers can converge to the same symptoms of schizophrenia, suggesting that the primary cause of the disease can be highly individual. Schizophrenia-related biomarkers include measurable biochemical changes induced by stress (elevated allostatic load), mitochondrial dysfunction, neuroinflammation, oxidative and nitrosative stress, and circadian rhythm disturbances. Here is a summary of selected valid biological hypotheses of schizophrenia formulated based on risk factors and biomarkers, neurodevelopment, neuroplasticity, brain chemistry, and antipsychotic medication. The integrative neurodevelopmental-vulnerability-neurochemical model is based on current knowledge of the neurobiology of the onset and progression of the disease and the effects of antipsychotics and psychotomimetics and reflects the complex and multifactorial nature of schizophrenia.

Targeting inflammation: a potential approach for the treatment of depression

Major depressive disorder (MDD) or Depression is one of the serious neuropsychiatric disorders affecting over 280 million people worldwide. It is 4th important cause of disability, poor quality of life, and economic burden. Women are more affected with the depression as compared to men and severe depression can lead to suicide. Most of the antidepressants predominantly work through the modulation on the availability of monoaminergic neurotransmitter (NTs) levels in the synapse. Current antidepressants have limited efficacy and tolerability. Moreover, treatment resistant depression (TRD) is one of the main causes for failure of standard marketed antidepressants. Recently, inflammation has also emerged as a crucial factor in pathological progression of depression. Proinflammatory cytokine levels are increased in depressive patients. Antidepressant treatment may attenuate depression via modulation of pathways of inflammation, transformation in structure of brain, and synaptic plasticity. Hence, targeting inflammation may be emerged as an effective approach for the treatment of depression. The present review article will focus on the preclinical and clinical studies that targets inflammation. In addition, it also concentrates on the therapeutic approaches' that targets depression via influence on the inflammatory signaling pathways. Graphical abstract demonstrate the role of various factors in the progression and neuroinflammation, oxidative stress. It also exhibits the association of neuroinflammation, oxidative stress with depression.

Anti-Inflammatory Therapy as a Promising Target in Neuropsychiatric Disorders

This chapter analyzes the therapeutic potential of current anti-inflammatory drugs in treating psychiatric diseases from a neuro-immunological perspective. Based on the bidirectional brain-immune system relationship, the rationale is that a dysregulated inflammation contributes to the pathogenesis of psychiatric and neurological disorders, while the immunology function is associated with psychological variables like stress, affective disorders, and psychosis. Under certain social, psychological, and environmental conditions and biological factors, a healthy inflammatory response and the associated "sickness behavior," which are aimed to resolve a physical injury and microbial threat, become harmful to the central nervous system. The features and mechanisms of the inflammatory response are described across the main mental illnesses with a special emphasis on the profile of cytokines and the function of the HPA axis. Next, it is reviewed the potential clinical utility of immunotherapy (cytokine agonists and antagonists), glucocorticoids, unconventional anti-inflammatory agents (statins, minocycline, statins, and polyunsaturated fatty acids (PUFAs)), the nonsteroidal anti-inflammatory drugs (NSAIDs), and particularly celecoxib, a selective cyclooxygenase-2 (Cox-2) inhibitor, as adjuvants of conventional psychiatric medications. The implementation of anti-inflammatory therapies holds great promise in psychiatry. Because the inflammatory background may account for the etiology and/or progression of psychiatric disorders only in a subset of patients, there is a need to elucidate the immune underpinnings of the mental illness progression, relapse, and remission. The identification of immune-related bio-signatures will ideally assist in the stratification of the psychiatric patient to predict the risk of mental disease, the prognosis, and the response to anti-inflammatory therapy.

Acetylsalicylic Acid-Primus Inter Pares in Pharmacology

Acetylsalicylic acid (ASA) is one of the first drugs to be obtained by synthesis while being the most used. It has experienced the longest lasting commercial success and is considered the most popular drug of the modern era. ASA, originally used as an anti-inflammatory medication, nowadays is predominantly used as an antiplatelet agent for prophylaxis in cardiac patients. Many studies show that the benefits of using ASA far outweigh the potential risk of side effects. With particular emphasis on the possibility of ASA repositioning for new therapies, extending the indications for use beyond the diseases from the spectrum of atherosclerotic diseases, such as cancer, requires shifting the benefit-risk ratio, although very good, even more towards safety. Interesting activities consisting not only of changing the formulation but also modifying the drug molecule seem to be an important goal of the 21st century. ASA has become a milestone in two important fields: pharmacy and medicine. For a pharmacist, ASA is a long-used drug for which individual indications are practically maintained. For a doctor, acetylsalicylic acid is primarily an antiplatelet drug that saves millions of lives of patients with coronary heart disease or after a stroke. These facts do not exempt us from improving therapeutic methods based on ASA, the main goal of which is to reduce the risk of side effects, as well as to extend effectiveness. Modified acetylsalicylic acid molecules already seem to be a promising therapeutic option.

Pharmacological Treatment for Neuroinflammation in Stress-Related Disorder

Stress is an organism’s response to a biological or psychological stressor, a method of responding to threats. The autonomic nervous system and hypothalamic–pituitary–adrenal axis (HPA axis) regulate adaptation to acute stress and secrete hormones and excitatory amino acids. This process can induce excessive inflammatory reactions to the central nervous system (CNS) by HPA axis, glutamate, renin-angiotensin system (RAS) etc., under persistent stress conditions, resulting in neuroinflammation. Therefore, in order to treat stress-related neuroinflammation, the improvement effects of several mechanisms of receptor antagonist and pharmacological anti-inflammation treatment were studied. The N-methyl-D-aspartate (NMDA) receptor antagonist, peroxisome proliferator-activated receptor agonist, angiotensin-converting enzyme inhibitor etc., effectively improved neuroinflammation. The interesting fact is that not only can direct anti-inflammation treatment improve neuroinflammation, but so can stress reduction or pharmacological antidepressants. The antidepressant treatments, including selective serotonin reuptake inhibitors (SSRI), also helped improve stress-related neuroinflammation. It presents the direction of future development of stress-related neuroinflammation drugs. Therefore, in this review, the mechanism of stress-related neuroinflammation and pharmacological treatment candidates for it were reviewed. In addition, treatment candidates that have not yet been verified but indicate possibilities were also reviewed.

The treatment of depression - searching for new ideas

Depression is a severe mental health problem that affects people regardless of social status or education, is associated with changes in mood and behavior, and can result in a suicide attempt. Therapy of depressive disorders is based mainly on drugs discovered in the 1960s and early 1970s. Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are frontline pharmacological strategies for the medical treatment of depression. In addition, approved by FDA in 2019, esketamine [as nasal spray; N-methyl-D-aspartate (NMDA) receptors antagonist with additional effects on α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, L-type voltage-dependent calcium channel (L-VDCC), opioid receptors, and monoaminergic receptors] is an essential compound in suicide and drug-resistant depression. However, the treatment of depression is burdened with severe side effects, and in many cases, it is ineffective. An equally important issue is the choice of antidepressant therapy in people with comorbid somatic diseases, for example, due to possible interactions with the patient's other drugs. Therefore, there is a great need for new antidepressants with different mechanisms of action and the need to refine the search for new substances. The purpose of this review was to discuss new research directions and new trends that dominate laboratories worldwide. We have reviewed the literature to present new points on the pharmacological target of substances with antidepressant activity. In addition, we propose a new perspective on depressive therapies.

Lipid-Based Molecules on Signaling Pathways in Autism Spectrum Disorder

The signaling pathways associated with lipid metabolism contribute to the pathophysiology of autism spectrum disorder (ASD) and provide insights for devising new therapeutic strategies. Prostaglandin E2 is a membrane-derived lipid molecule that contributes to developing ASD associated with canonical Wnt signaling. Cyclooxygenase-2 plays a key role in neuroinflammation and is implicated in the pathogenesis of neurodevelopmental diseases, such as ASD. The endocannabinoid system maintains a balance between inflammatory and redox status and synaptic plasticity and is a potential target for ASD pathophysiology. Redox signaling refers to specific and usually reversible oxidation–reduction reactions, some of which are also involved in pathways accounting for the abnormal behavior observed in ASD. Redox signaling and redox status-sensitive transcription factors contribute to the pathophysiology of ASD. Cannabinoids regulate the redox balance by altering the levels and activity of antioxidant molecules via ROS-producing NADPH oxidase (NOX) and ROS-scavenging superoxide dismutase enzymes. These signaling cascades integrate a broad range of neurodevelopmental processes that may be involved in the pathophysiology of ASD. Based on these pathways, we highlight putative targets that may be used for devising novel therapeutic interventions for ASD.

COX-2 pathway is upregulated in ultra-high risk individuals for psychosis

BACKGROUND

The identification of Ultra-High Risk (UHR) individuals is thought to be useful for early intervention to improve psychosis outcomes. However, transition rates vary widely, and there is an effort to make these criteria more specific and accurate. Neuroinflammation has been discussed in the pathophysiology of psychosis. The metabolism of eicosanoids is a key process in inflammatory states. Therefore, we investigated whether the study of the inflammatory COX-2 pathway through the quantification of the eicosanoid levels can be a useful approach for the characterisation of UHR individuals.

METHODS

One hundred and twenty-two individuals were included in this study (67 UHR and 55 controls) based on performance on the Prodromal Questionnaire. UHR status was assessed by Structured Interview for Prodromal Syndromes (SIPS). We determined the levels of Prostaglandin F_2α (PGF_2α), Prostaglandin E₂ (PGE₂), and Thromboxane B₂ (TxB₂) in plasma using ELISA assays.

RESULTS

Concentrations of PGE₂ and TxB₂ were increased in UHR compared to controls (p = 0.01 and p < 0.05, respectively). PGE₂ and PGF_2α levels were correlated to negative symptoms (p < 0.01 and p < 0.05), whereas TxB₂ correlated with positive symptoms (p = 0.05) as assessed by the SIPS.

CONCLUSIONS

Our findings suggest that overactivation of the COX-2 pathway may be related to an increased risk for psychosis. However, our data do not allow us to draw conclusions related to the cause-effect mechanisms. Future studies should determine whether the levels of the eicosanoids have a predictive value for the transition of UHR to frank psychosis.

Hippocampal Over-Expression of Cyclooxygenase-2 (COX-2) Is Associated with Susceptibility to Stress-Induced Anhedonia in Mice

The phenomenon of individual variability in susceptibility/resilience to stress and depression, in which the hippocampus plays a pivotal role, is attracting increasing attention. We investigated the potential role of hippocampal cyclooxygenase-2 (COX-2), which regulates plasticity, neuroimmune function, and stress responses that are all linked to this risk dichotomy. We used a four-week-long chronic mild stress (CMS) paradigm, in which mice could be stratified according to their susceptibility/resilience to anhedonia, a key feature of depression, to investigate hippocampal expression of COX-2, a marker of microglial activation Iba-1, and the proliferation marker Ki67. Rat exposure, social defeat, restraints, and tail suspension were used as stressors. We compared the effects of treatment with either the selective COX-2 inhibitor celecoxib (30 mg/kg/day) or citalopram (15 mg/kg/day). For the celecoxib and vehicle-treated mice, the Porsolt test was used. Anhedonic (susceptible) but not non-anhedonic (resilient) animals exhibited elevated COX-2 mRNA levels, increased numbers of COX-2 and Iba-1-positive cells in the dentate gyrus and the CA1 area, and decreased numbers of Ki67-positive cells in the subgranular zone of the hippocampus. Drug treatment decreased the percentage of anhedonic mice, normalized swimming activity, reduced behavioral despair, and improved conditioned fear memory. Hippocampal over-expression of COX-2 is associated with susceptibility to stress-induced anhedonia, and its pharmacological inhibition with celecoxib has antidepressant effects that are similar in size to those of citalopram.

Celecoxib versus placebo as an adjunct to treatment-as-usual in children and youth with obsessive-compulsive disorder: protocol for a single-site randomised quadruple-blind phase II study

BACKGROUND

Cyclooxygenase (COX) enzymes oxidise arachidonic acid to prostaglandins, which modulate neuronal function and inflammation in the central nervous system. Consensus guidelines suggest non-steroidal anti-inflammatory drugs as a possible adjunctive approach in adults with obsessive-compulsive disorder (OCD) and in children with acute-onset OCD subtypes. However, there is limited evidence to support this approach. The primary objective of this study is to determine the efficacy of the COX-2-selective inhibitor celecoxib as an adjunct to treatment-as-usual in children and youth with moderate-to-severe OCD. The safety of this intervention including adverse events will also be systematically assessed.

METHODS

The Adjunctive CElecoxib in childhood-onset OCD (ACE-OCD) study is a single-centre randomised, quadruple-blind, placebo-controlled superiority trial with two parallel groups: celecoxib 100 mg twice daily and placebo. Treatments will be added to participants' routine clinical care, which will not change over the course of the study. Target recruitment is 80 participants ages 7-18 with no recent treatment changes. The primary outcome is OCD severity after 12 weeks of treatment, measured by clinician-administered Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS). Secondary outcomes include CY-BOCS score after 6 weeks; difference in the proportion of participants achieving a clinically meaningful response or remission; mean clinical global impression of severity and improvement after 6 and 12 weeks; and proportion of participants reporting adverse events possibly or probably related to the study intervention. The primary analyses, carried out according to intention-to-treat principles, will compare the celecoxib to placebo group on each outcome of interest, adjusting for baseline scores using analysis of covariance or logistic regression. Participants will be offered a 12-week open-label celecoxib extension and will be invited to participate in an ancillary study for biomarker analyses.

ETHICS AND DISSEMINATION

This protocol has been approved by the University of British Columbia Children's and Women's Research Ethics Board and has received a No Objection Letter from Health Canada. The findings will be disseminated in peer-reviewed journals and presentations to multiple stakeholders including patients, parents and healthcare providers.

TRIAL REGISTRATION NUMBER

NCT04673578.

Emerging Role of Flavonoids as the Treatment of Depression

Depression is one of the most frequently observed psychological disorders, affecting thoughts, feelings, behavior and a sense of well-being in person. As per the WHO, it is projected to be the primitive cause of various other diseases by 2030. Clinically, depression is treated by various types of synthetic medicines that have several limitations such as side-effects, slow-onset action, poor remission and response rates due to complicated pathophysiology involved with depression. Further, clinically, patients cannot be given the treatment unless it affects adversely the job or family. In addition, synthetic drugs are usually single targeted drugs. Unlike synthetic medicaments, there are many plants that have flavonoids and producing action on multiple molecular targets and exhibit anti-depressant action by affecting multiple neuronal transmissions or pathways such as noradrenergic, serotonergic, GABAnergic and dopaminergic; inhibition of monoamine oxidase and tropomyosin receptor kinase B; simultaneous increase in nerve growth and brain-derived neurotrophic factors. Such herbal drugs with flavonoids are likely to be useful in patients with sub-clinical depression. This review is an attempt to analyze pre-clinical studies, structural activity relationship and characteristics of reported isolated flavonoids, which may be considered for clinical trials for the development of therapeutically useful antidepressant.

Alpha-Synuclein, cyclooxygenase-2 and prostaglandins-EP2 receptors as neuroinflammatory biomarkers of autism spectrum disorders: Use of combined ROC curves to increase their diagnostic values

BACKGROUND

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social interaction and restricted and repetitive behaviors. Neuroinflammation and abnormal lipid mediators have been identified in multiple investigations as an acknowledged etiological mechanism of ASD that can be targeted for therapeutic intervention.

METHODS

In this study, multiple regression and combined receiver operating characteristic (ROC) curve analyses were used to determine the relationship between the neuroinflammatory marker α-synuclein and lipid mediator markers related to inflammation induction, such as cyclooxygenase-2 and prostaglandin-EP2 receptors, in the etiology of ASD. Additionally, the study aimed to determine the linear combination that maximizes the partial area under ROC curves for a set of markers. Forty children with ASD and 40 age- and sex-matched controls were enrolled in the study. Using ELISA, the levels of α-synuclein, cyclo-oxygenase-2, and prostaglandin-EP2 receptors were measured in the plasma of both groups. Statistical analyses using ROC curves and multiple and logistic regression models were performed.

RESULTS

A remarkable increase in the area under the curve was observed using combined ROC curve analyses. Moreover, higher specificity and sensitivity of the combined markers were reported.

CONCLUSIONS

The present study indicates that measurement of the predictive value of selected biomarkers related to neuroinflammation and lipid metabolism in children with ASD using a ROC curve analysis should lead to a better understanding of the etiological mechanism of ASD and its link with metabolism. This information may facilitate early diagnosis and intervention.

A network meta-analysis of stress mediators in suicide behaviour

Stress homeostatic mediators are the most consistently anomalous biomarkers observed in suicide and may therefore point to a common 'core biology' of stress susceptibility, and suicidal behaviour. Previously reported meta-analyses have demonstrated aberrant levels of stress cortisol and inflammatory cytokines in suicide patients compared to controls, and significant associations between the stress regulator FK506-binding protein 51 (FKBP5) gene and suicidal behaviour. Although these independent studies were investigated as separate entities in suicide, stress mediators interact in a dynamic system, collectively giving rise to system changes physiologically, and ultimately psychologically and behaviourally. It is therefore important to study the dynamic network these stress mediators. Network meta-analysis allows for the simultaneous comparison of more than two biological mediators, and for comparisons to be made between mediators that have not been directly compared before, using previously reported, pooled meta data. Such network approaches may help study the complex biological phenomena of suicide and may provide better prediction of biological risk of suicidal states.

METHODS

This study aimed to establish the comparative relationships between key stress mediators in suicidal patients compared to non-suicidal controls using a random-effects network meta-analysis approach.. The key stress mediators included cortisol, six inflammatory markers (interleukin-6 (IL-6), interleukin-4 (IL-4), interleukin-2 (IL-2), tumour necrosis factor-a (TNF-α), interferon (IFN-y) and transforming growth factor β (TGF-β), and the FKBP5 single nucleotide polymorphism (SNP) allele. Data was derived from three previously published meta-analysis. The study population comprised of 1348 suicidal patients, defined as suicide attempters, completers, or patients with severe suicidal ideation, and 1750 non-suicidal controls, defined as healthy controls and psychiatric patients without suicidal ideation or previous attempts.

RESULTS

Pair-wise indirect effects of stress mediators in suicide compared to controls demonstrated that relative to the effect of the FKBP5 risk SNP allele on suicide risk, the magnitude of differences (suicide vs control) for the levels of IL-2 (SMD -0.72; 95% CI, -0.135 to -0.09 and IL-4 (SMD -0.71; 95% CI, -1.34 to -0.08) were significantly smaller (with 95% confidence intervals not crossing the null). The comparative relationships between stress mediators in suicidal behaviour demonstrates that the dynamic stress network relationship is dysregulated in suicide patients when compared to controls.

CONCLUSIONS

This model suggests that a genetic stress susceptibility with downstream abnormal cortisol stress axis functioning, together with anomalous interactions between the inflammatory system, may be one of the neurobiological correlates of suicide behaviour. This biological state may leave the individual physiologically susceptible and unable to cope with environmental stressors, which is consistent with the stress-diathesis hypothesis of suicide behaviour.

Inflammatory neuropsychiatric disorders and COVID-19 neuroinflammation

Neuropsychiatric sequalae to coronavirus disease 2019 (COVID-19) infection are beginning to emerge, like previous Spanish influenza and severe acute respiratory syndrome episodes. Streptococcal infection in paediatric patients causing obsessive compulsive disorder (PANDAS) is another recent example of an infection-based psychiatric disorder. Inflammation associated with neuropsychiatric disorders has been previously reported but there is no standard clinical management approach established. Part of the reason is that it is unclear what factors determine the specific neuronal vulnerability and the efficacy of anti-inflammatory treatment in neuroinflammation. The emerging COVID-19 data suggested that in the acute stage, widespread neuronal damage appears to be the result of abnormal and overactive immune responses and cytokine storm is associated with poor prognosis. It is still too early to know if there are long-term-specific neuronal or brain regional damages associated with COVID-19, resulting in distinct neuropsychiatric disorders. In several major psychiatric disorders where neuroinflammation is present, patients with abnormal inflammatory markers may also experience less than favourable response or treatment resistance when standard treatment is used alone. Evidence regarding the benefits of co-administered anti-inflammatory agents such as COX-2 inhibitor is encouraging in selected patients though may not benefit others. Disease-modifying therapies are increasingly being applied to neuropsychiatric diseases characterised by abnormal or hyperreactive immune responses. Adjunct anti-inflammatory treatment may benefit selected patients and is definitely an important component of clinical management in the presence of neuroinflammation.

[Prospects for the use of drugs with anti-inflammatory properties for the treatment of depression]

The review briefly summarizes experimental and preclinical data of the role of pro-inflammatory cytokines in triggering pathophysiological changes associated with depression, primarily major depressive disorder (MDD), as well as the possibility of using anti-inflammatory drugs as antidepressants.

Immunity and Gilles de la Tourette syndrome: A systematic review and meta-analysis of evidence for immune implications in Tourette syndrome

BACKGROUND AND PURPOSE

The neurobiology of Gilles de la Tourette syndrome (GTS) is known to involve corticostriatal loops possibly under genetic control. Less is known about possible environmental triggers of GTS. Specifically, immune-related events following possible environmental inducers have been evoked, but important controversies still exist. In this systematic review and meta-analysis, we looked for evidence in favor of such possibilities.

METHODS

We performed a systematic review and meta-analysis of all immunological data in PubMed.

RESULTS

We found large discrepancies concerning immune dysfunctions in GTS, and meta-analyzing cytokines data did not allow us to conclude there is an involvement of specific cytokines in GTS neurobiology. When looking specifically at pediatric autoimmune neuropsychiatric disorder associated with streptococcus/pediatric acute onset neuropsychiatric syndrome, we found some important evidence of a possible infectious involvement but in a limited number of studies. Our meta-analysis found an increased level of anti-streptolysin O antibodies in GTS patients, but the level of anti-DNase B antibodies was not increased.

CONCLUSIONS

Too many questions still exist to allow us to definitively reach the conclusion that there is an infectious and immunological etiology in GTS. Much work is still needed to elucidate the possible role of immunology in GTS neurobiology and to favor immunological treatment rather than classical treatment.

The role of the microbiota-gut-brain axis in neuropsychiatric disorders

The microbiota-gut-brain axis is a bidirectional signaling mechanism between the gastrointestinal tract and the central nervous system. The complexity of the intestinal ecosystem is extraordinary; it comprises more than 100 trillion microbial cells that inhabit the small and large intestine, and this interaction between microbiota and intestinal epithelium can cause physiological changes in the brain and influence mood and behavior. Currently, there has been an emphasis on how such interactions affect mental health. Evidence indicates that intestinal microbiota are involved in neurological and psychiatric disorders. This review covers evidence for the influence of gut microbiota on the brain and behavior in Alzheimer disease, dementia, anxiety, autism spectrum disorder, bipolar disorder, major depressive disorder, Parkinson’s disease, and schizophrenia. The primary focus is on the pathways involved in intestinal metabolites of microbial origin, including short-chain fatty acids, tryptophan metabolites, and bacterial components that can activate the host’s immune system. We also list clinical evidence regarding prebiotics, probiotics, and fecal microbiota transplantation as adjuvant therapies for neuropsychiatric disorders.

Bioinformatics analysis of a TF-miRNA-lncRNA regulatory network in major depressive disorder

Major depressive disorder (MDD) is a highly prevalent disease and one of the main causes of disability worldwide. Although many studies have partially revealed the occurrence and development process of MDD, the pathogeny and molecular mechanisms are not fully understood. Weighted gene coexpression network analysis (WGCNA) was used to explore the co-expression modules and hub genes in MDD. A protein-protein interaction (PPI) network of the most significant module and a TF-miRNA-lncRNA regulatory network of MDD were constructed using bioinformatics analysis tools. A KEGG pathway and gene ontology (GO) functional enrichment analysis of the genes in the significant module was performed using DAVID. Five hub genes in the PPI network and 10 genes in the TF-miRNA-lncRNA regulatory network with high degree values were identified, which may provide new insights for the investigation of key pathways, diagnostic bio-markers, and therapeutic targets of MDD. This study brings a novel perspective and provides valuable information to explore the molecular mechanism of MDD.

Major Depressive Disorder in Older Patients as an Inflammatory Disorder: Implications for the Pharmacological Management of Geriatric Depression

Depression is a common and highly disabling condition in older adults. It is a heterogenous disorder and there is emerging evidence of a link between inflammation and depression in older patients, with a possible inflammatory subtype of depression. Persistent low-level inflammation, from several sources including psychological distress and chronic disease, can disrupt monoaminergic and glutaminergic systems to create dysfunctional brain networks. Despite the evidence for the role of inflammation in depression, there is insufficient evidence to recommend use of any putative anti-inflammatory agent in the treatment of depression in older adults at this stage. Further characterisation of markers of inflammation and stratification of participants with elevated rates of inflammatory markers in treatment trials is needed.

The Impact of Nutrients on Mental Health and Well-Being: Insights From the Literature

A good nutritional status is important for maintaining normal body function and preventing or mitigating the dysfunction induced by internal or external factors. Nutritional deficiencies often result in impaired function, and, conversely, intakes at recommended levels can resume or further enhance body functions. An increasing number of studies are revealing that diet and nutrition are critical not only for physiology and body composition, but also have significant effects on mood and mental well-being. In particular, Western dietary habits have been the object of several research studies focusing on the relationship between nutrition and mental health. This review aims to summarize the current knowledge about the relationship between the intake of specific micro- and macronutrients, including eicosapentaenoic acid, docosahexaenoic acid, alpha-tocopherol, magnesium and folic acid, and mental health, with particular reference to their beneficial effect on stress, sleep disorders, anxiety, mild cognitive impairment, as well as on neuropsychiatric disorders, all significantly affecting the quality of life of an increasing number of people. Overall data support a positive role for the nutrients mentioned above in the preservation of normal brain function and mental well-being, also through the control of neuroinflammation, and encourage their integration in a well-balanced and varied diet, accompanied by a healthy lifestyle. This strategy is of particular importance when considering the global human aging and that the brain suffers significantly from the life-long impact of stress factors.

R.ROSETTA: an interpretable machine learning framework

BACKGROUND

Machine learning involves strategies and algorithms that may assist bioinformatics analyses in terms of data mining and knowledge discovery. In several applications, viz. in Life Sciences, it is often more important to understand how a prediction was obtained rather than knowing what prediction was made. To this end so-called interpretable machine learning has been recently advocated. In this study, we implemented an interpretable machine learning package based on the rough set theory. An important aim of our work was provision of statistical properties of the models and their components.

RESULTS

We present the R.ROSETTA package, which is an R wrapper of ROSETTA framework. The original ROSETTA functions have been improved and adapted to the R programming environment. The package allows for building and analyzing non-linear interpretable machine learning models. R.ROSETTA gathers combinatorial statistics via rule-based modelling for accessible and transparent results, well-suited for adoption within the greater scientific community. The package also provides statistics and visualization tools that facilitate minimization of analysis bias and noise. The R.ROSETTA package is freely available at https://github.com/komorowskilab/R.ROSETTA . To illustrate the usage of the package, we applied it to a transcriptome dataset from an autism case-control study. Our tool provided hypotheses for potential co-predictive mechanisms among features that discerned phenotype classes. These co-predictors represented neurodevelopmental and autism-related genes.

CONCLUSIONS

R.ROSETTA provides new insights for interpretable machine learning analyses and knowledge-based systems. We demonstrated that our package facilitated detection of dependencies for autism-related genes. Although the sample application of R.ROSETTA illustrates transcriptome data analysis, the package can be used to analyze any data organized in decision tables.

Design and synthesis of 7-O-1,2,3-triazole hesperetin derivatives to relieve inflammation of acute liver injury in mice

Based on the previous research results of our research group, to further improve the anti-inflammatory activity of hesperetin, we substituted triazole at the 7-OH branch of hesperetin. We also evaluated the anti-inflammatory activity of 39 new hesperetin derivatives. All compounds showed inhibitory effects on nitric oxide (NO) and inflammatory factors in lipopolysaccharide-induced RAW264.7 cells. Compound d5 showed a strong inhibitory effect on NO (half maximal inhibitory concentration = 2.34 ± 0.7 μM) and tumor necrosis factor-α, interleukin (IL)-1β, and (IL-6). Structure-activity relationships indicate that 7-O-triazole is buried in a medium-sized hydrophobic cavity that binds to the receptor. Compound d5 can also reduce the reactive oxygen species production and significantly inhibit the expression of inducible NO synthase and cyclooxygenase-2 through the nuclear factor-κB signaling pathway. In vivo results indicate that d5 can reduce liver inflammation in mice with acute liver injury (ALI) induced by CCI₄. In conclusion, d5 may be a candidate drug for treating inflammation associated with ALI.

The Emerging Role of the Double-Edged Impact of Arachidonic Acid- Derived Eicosanoids in the Neuroinflammatory Background of Depression

Eicosanoids are arachidonic acid (AA) derivatives belonging to a family of lipid signalling mediators that are engaged in both physiological and pathological processes in the brain. Recently, their implication in the prolonged inflammatory response has become a focus of particular interest because, in contrast to acute inflammation, chronic inflammatory processes within the central nervous system (CNS) are crucial for the development of brain pathologies including depression. The synthesis of eicosanoids is catalysed primarily by cyclooxygenases (COX), which are involved in the production of pro-inflammatory AA metabolites, including prostaglandins and thromboxanes. Moreover, eicosanoid synthesis is catalysed by lipoxygenases (LOXs), which generate both leukotrienes and anti-inflammatory derivatives such as lipoxins. Thus, AA metabolites have double- edged pro-inflammatory and anti-inflammatory, pro-resolving properties, and an imbalance between these metabolites has been proposed as a contributor or even the basis for chronic neuroinflammatory effects. This review focuses on important evidence regarding eicosanoid-related pathways (with special emphasis on prostaglandins and lipoxins) that has added a new layer of complexity to the idea of targeting the double-edged AA-derivative pathways for therapeutic benefits in depression. We also sought to explore future research directions that can support a pro-resolving response to control the balance between eicosanoids and thus to reduce the chronic neuroinflammation that underlies at least a portion of depressive disorders.

Cyclooxygenase Inhibition Safety and Efficacy in Inflammation-Based Psychiatric Disorders

According to the World Health Organization, the major psychiatric and neurodevelopmental disorders include major depression, bipolar disorder, schizophrenia, and autism spectrum disorder. The potential role of inflammation in the onset and progression of these disorders is increasingly being studied. The use of non-steroidal anti-inflammatory drugs (NSAIDs), well-known cyclooxygenase (COX) inhibitors, combined with first-choice specific drugs have been long investigated. The adjunctive administration of COX inhibitors to classic clinical treatments seems to improve the prognosis of people who suffer from psychiatric disorders. In this review, a broad overview of the use of COX inhibitors in the treatment of inflammation-based psychiatric disorders is provided. For this purpose, a critical analysis of the use of COX inhibitors in the last ten years of clinical trials of the major psychiatric disorders was carried out.

The molecular mechanisms of celecoxib in tumor development

BACKGROUND

Clinical studies have shown that celecoxib can significantly inhibit the development of tumors, and basic experiments and in vitro experiments also provide a certain basis, but it is not clear how celecoxib inhibits tumor development in detail.

METHODS

A literature search of all major academic databases was conducted (PubMed, China National Knowledge Internet (CNKI), Wan-fang, China Science and Technology Journal Database (VIP), including the main research on the mechanisms of celecoxib on tumors.

RESULTS

Celecoxib can intervene in tumor development and reduce the formation of drug resistance through multiple molecular mechanisms.

CONCLUSION

Celecoxib mainly regulates the proliferation, migration, and invasion of tumor cells by inhibiting the cyclooxygenases-2/prostaglandin E2 signal axis and thereby inhibiting the phosphorylation of nuclear factor-κ-gene binding, Akt, signal transducer and activator of transcription and the expression of matrix metalloproteinase 2 and matrix metalloproteinase 9. Meanwhile, it was found that celecoxib could promote the apoptosis of tumor cells by enhancing mitochondrial oxidation, activating mitochondrial apoptosis process, promoting endoplasmic reticulum stress process, and autophagy. Celecoxib can also reduce the occurrence of drug resistance by increasing the sensitivity of cancer cells to chemotherapy drugs.

Cyclooxygenase-2 inhibition prevents stress induced amygdala activation and anxiety-like behavior

Stress is a major risk factor for the development and exacerbation of mood and anxiety disorders, and recent studies have suggested inflammatory contributions to the pathogenesis of depression. Interestingly, pharmacological inhibition of cyclooxygenase-2 (COX-2) has shown promise in the treatment of affective disorders in small scale clinical studies; however, the mechanisms by which COX-2 inhibition affects behavioral domains relevant to affective disorders are not well understood. Here, we examined the effects of pharmacological inhibition of COX-2 with the highly selective inhibitor Lumiracoxib (LMX) on anxiety-like behavior and in vivo basolateral amygdala (BLA) neural activity in response to acute restraint stress exposure. In male mice, pretreatment with LMX prevented the increase in BLA calcium transients induced by restraint stress and prevented anxiogenic behavior seen after restraint stress exposure. Specifically, acute injection of LMX 5 mg kg^-1 reduced anxiety-like behavior in the light-dark box (LD) and elevated-zero maze (EZM). In addition, in vivo fiber photometry studies showed that acute stress increased calcium transients and the predicted action potential frequency of BLA neurons, which was also normalized by acute LMX pretreatment. These findings indicate pharmacological inhibition of COX-2 can prevent acute stress-induced increase in BLA cellular activity and anxiety-like behavior and provides insights into the neural mechanisms by which COX-2 inhibition could affect anxiety domain symptoms in patients with affective disorders.

Therapeutic potential of sulfur-containing natural products in inflammatory diseases

Owing to the prevalence of chronic inflammation and its related disorders, there is a demand for novel therapeutic agents capable of preventing or suppressing inflammation. Natural products (NPs) are well established as an important resource for drug development and provide an almost infinite array of molecular entities. Sulfur-containing NPs (i.e., NPs containing one or more sulfur atoms) are abundant throughout nature, from bacteria to animals. The aim of this review was to survey the emerging evidence on role of sulfur-containing NPs, such as glutathione, garlic-derived sulfur compounds, Epipolythiodioxopiperazines (EPTs), Isothiocyanates (ITCs), and Ergothioneine (EGT), in the control of inflammation and to determine the possible underlying mechanisms. A discussion of how hydrogen sulfide (H₂S), an endogenous gaseous signaling molecule, links sulfur-containing NPs and their anti-inflammatory action is also performed. This review may help to further the development of sulfur-based compounds by providing a guide for structure-activity relationship-based modification for use in modern medicinal chemistry. However, as this field is still in its infancy, the review is concluded by an overview of the progression of these promising entities as therapeutic agents.

Prospective associations between hsCRP and GlycA inflammatory biomarkers and depression: The Brazilian longitudinal study of adult health (ELSA-Brasil)

BACKGROUND

Although low-grade inflammation is associated with onset and persistence of depression, most biomarkers display modest predictive effects. GlycA (glycoprotein acetylation) is a unique metabolomic composite of pro-inflammatory acute-phase glycoproteins. We hypothesized that GlycA levels would predict depression incidence, remission and persistence, with higher accuracy than high-sensitivity c-reactive protein (hsCRP). We also explored the additive predictive value of GlycA above and beyond hsCRP.

METHODS

Cohort design using the sample of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)'s São Paulo site. Baseline GlycA and hsCRP levels were measured in blood plasma. Depression incidence, remission, and persistence were assessed using the Clinical Interview Scheduled Revised (CIS-R) at two time points separated by a mean of 3.8 years. Multivariable Poisson, logistic and linear regression models were used for prediction. Models were adjusted for sociodemographic and clinical confounders, including age, gender, ethnicity, education, cardiovascular assessments, antidepressant and anti-inflammatory drug use, anxiety disorders, alcohol use, and body mass index.

RESULTS

We included 4,364 participants (53.2% females, mean age 51.4 ± 8.9 years) with no autoimmune disorders. GlycA robustly predicted depression persistence (relative risk of 7.28, 95% confidence interval 1.33-45.57, p = 0.023 in the fully-adjusted model), but not depression onset. Although hsCRP also predicted depression persistence, its effects were fully explained by confounders and by GlycA levels. GlycA also predicted worsening of depressive symptoms in depressed patients and depression persistence vs. remission in fully-adjusted models.

LIMITATIONS

Brief depressive episodes could not be measured by our assessments.

CONCLUSIONS

GlycA might be a new inflammatory prognosis biomarker for depression.