Inhibition of Microglial Activation by Amitriptyline and Doxepin in Interferon-β Pre-Treated Astrocyte–Microglia Co-Culture Model of Inflammation

Linking depression and neuroinflammation: Crosstalk between glial cells

The inflammatory hypothesis is one of the more widely accepted pathogenesis of depression. Glia plays an important immunomodulatory role in neuroinflammation, mediating interactions between the immune system and the central nervous system (CNS). Glial cell-driven neuroinflammation is not only an important pathological change in depression, but also a potential therapeutic target. This review discusses the association between depression and glial cell-induced neuroinflammation and elucidates the role of glial cell crosstalk in neuroinflammation. Firstly, we focus on the role of glial cells in neuroinflammation in depression and glial cell interactions; secondly, we categorize changes in different glial cells in animal models of depression and depressed patients, focusing on how glial cells mediate inflammatory responses and exacerbate depressive symptoms; Thirdly, we review how conventional and novel antidepressants affect the phenotype and function of glial cells, thereby exerting anti-inflammatory activity; finally, we discuss the role of the gut-brain axis in glial cell function and depression, and objectively analyze the problems that remain in current antidepressant therapy. This review aims to provide an objective analysis of how glial cell cross-talk may mediate neuroinflammation and thereby influence pathologic progression of depression. It is concluded that a novel therapeutic strategy may be to ameliorate glial cell-mediated inflammatory responses.

rTMS ameliorates CUMS-induced anxiety-depression-like behaviour and cognitive dysfunction in rats by modulating the COX-2/PGE2 signalling pathway

BACKGROUND

rTMS is a safe and effective neuromodulation method for treating depression, but the specifics of its antidepressant effects and the underlying mechanisms remain uncertain.

METHODS

Male SD rats were randomly divided into four groups: control group, CUMS group, CUMS + rTMS (10 Hz) group, and CUMS + celecoxib (25 mg/kg, as a positive control) group. Depression-like behavior was assessed by weight change, SPT, and FST; anxiety by OFT and EPM; and cognitive function by the Y-maze. WB, IF, ELISA, and qPCR were used to observe changes in COX-2/PGE2 signaling pathway-related proteins, inflammatory factors, and the activation of astrocytes and microglia in the hippocampus of rats.

RESULTS

Compared to the control group, rats in the CUMS group exhibited significant anxiety-depression-like behavior and cognitive dysfunction. Compared to the CUMS group, rTMS and celecoxib interventions improved anxiety-depression-like behavior and cognitive dysfunction, reduced the expression of microglia and astrocytes, reversed the upregulation of pro-inflammatory factors (IL-1β, IL-6, TNF-α), and downregulated the expression of proteins related to the COX-2/PGE2 signaling pathway in CUMS-induced rats.

CONCLUSIONS

The study demonstrated that rTMS could improve anxiety-depression-like behavior and cognitive dysfunction in rats by modulating the COX-2/PGE2 pathway.

Influence of antipsychotic drugs on microglia-mediated neuroinflammation in schizophrenia: perspectives in an astrocyte-microglia co-culture model

Schizophrenia is a severe mental disorder with a strong lifetime impact on patients' health and wellbeing. Usually, symptomatic treatment includes typical or atypical antipsychotics. Study findings show an involvement of low-grade inflammation (blood, brain parenchyma, and cerebrospinal fluid) in schizophrenia. Moreover, experimental and neuropathological evidence suggests that reactive microglia, which are the main resident immune cells of the central nervous system (CNS), have a negative impact on the differentiation and function of oligodendrocytes, glial progenitor cells, and astrocytes, which results in the disruption of neuronal networks and dysregulated synaptic transmission, contributing to the pathophysiology of schizophrenia. Here, the role of microglial cells related to neuroinflammation in schizophrenia was discussed to be essential. This review aims to summarize the evidence for the influence of antipsychotics on microglial inflammatory mechanisms in schizophrenia. Furthermore, we propose an established astrocyte-microglia co-culture model for testing regulatory mechanisms and examining the effects of antipsychotics on glia-mediated neuroinflammation. This could lead to a better understanding of how typical and atypical antipsychotics can be used to address positive and negative symptoms in schizophrenia and comorbidities like inflammatory diseases or the status of low-grade inflammation.

Clinical Insights and Radiological Features on Multiple Sclerosis Comorbid with Migraine

Background: Multiple sclerosis (MS) and migraine are neurological diseases, affecting young women. Migraine is the most prevalent type of headache in people with MS (pwMS). Objectives: The aim of this review is to describe the clinical, radiological, and therapeutic features of MS and migraine comorbidity. The clinical section focuses on the characteristics of migraine in pwMS and of MS in co-occurrence with migraine, and on the presence of other possible comorbidities. The radiological section deals with the differential diagnosis of white matter lesions and changes in connectivity patterns on brain magnetic resonanceto investigate a possible link between MS and migraine. The therapeutic section evaluates the effects of MS-disease-modifying therapies on migraine and of prophylactic migraine treatments on MS. Methods: The literature search was conducted using PubMed as an electronic database. The papers that reported relevant clinical, radiological and therapeutic findings were selected. Results: Among 1351 results retrieved, at the end of screening procedures, 34 studies were selected. Migraine can impact the perception of some symptoms and the presence of some comorbidities, particularly relevant in MS. Furthermore, migraine and MS share some radiological features, leading to diagnostic challenges, however identifying some lesion characteristics and changes in the connectivity pathway may be supportive. Medications for migraine and MS should be administered considering both the adverse events and multiple drug interactions. Conclusions: The data emerging from this review illustrate the research efforts aimed at providing valuable insights into accurate diagnosis, effective clinical management, and the definition of targeted treatment schedules that could improve the quality of life for pwMS with migraine.

Role of Inflammatory Mechanisms in Major Depressive Disorder: From Etiology to Potential Pharmacological Targets

The involvement of central and peripheral inflammation in the pathogenesis and prognosis of major depressive disorder (MDD) has been demonstrated. The increase of pro-inflammatory cytokines (interleukin (IL)-1β, IL-6, IL-18, and TNF-α) in individuals with depression may elicit neuroinflammatory processes and peripheral inflammation, mechanisms that, in turn, can contribute to gut microbiota dysbiosis. Together, neuroinflammation and gut dysbiosis induce alterations in tryptophan metabolism, culminating in decreased serotonin synthesis, impairments in neuroplasticity-related mechanisms, and glutamate-mediated excitotoxicity. This review aims to highlight the inflammatory mechanisms (neuroinflammation, peripheral inflammation, and gut dysbiosis) involved in the pathophysiology of MDD and to explore novel anti-inflammatory therapeutic approaches for this psychiatric disturbance. Several lines of evidence have indicated that in addition to antidepressants, physical exercise, probiotics, and nutraceuticals (agmatine, ascorbic acid, and vitamin D) possess anti-inflammatory effects that may contribute to their antidepressant properties. Further studies are necessary to explore the therapeutic benefits of these alternative therapies for MDD.