Search Results (84)

Major depression (MD) is associated with chronic inflammation and impaired neuroplasticity; however, the cellular mechanisms underlying antidepressant action remain incompletely understood. We performed transcriptomic profiling and functional validation in human microglia treated with venlafaxine (VEN) and vortioxetine (VOR), or with stable ST3GAL5 overexpression (ST3GAL5OE). Differential expression analysis, enrichment studies, and functional assays using NF-κB-RE-NlucP and SIE-NlucP reporter lines were conducted to assess the impact on inflammatory signaling. Microarray analysis identified 41 genes consistently upregulated and 316 consistently downregulated across VEN, VOR, and ST3GAL5OE conditions. Upregulated genes were enriched for synaptic organization, whereas downregulated genes were associated with nitric oxide biosynthesis and pro-inflammatory pathways, including Rap1, MAPK, and PI3K-Akt signaling. Functional assays confirmed that VEN and VOR suppressed cytokine-induced NF-κB and STAT3 activation, effects that were recapitulated by exogenous GM3 treatment and ST3GAL5 overexpression. Chronic exposure to VEN or VOR produced more modest, pathway-specific suppression, supporting convergence on the ST3GAL5–GM3 axis. These findings extend the conventional monoaminergic model of antidepressant action by highlighting the ST3GAL5–GM3 lipid remodeling axis as a novel regulatory pathway that attenuates microglial inflammatory signaling. Although validation in primary microglia and in vivo models is required, our results suggest that this axis could serve as both a therapeutic target and a candidate biomarker for inflammation-associated MD. Full article

Traumatic brain injury (TBI) is a major source of disability worldwide, with cognitive and memory deficits being pervasive after injury. The hippocampus, a major structure involved in learning and memory, is particularly vulnerable to TBI, and cellular dysfunction within the hippocampal dentate gyrus is believed to be a major contributor to cognitive deficits after TBI. However, there is little known about the transcriptomic changes occurring directly within the dentate gyrus at subacute-to-chronic timepoints after TBI. To address this, we performed bulk RNA sequencing and single-nucleus RNA sequencing of the isolated dentate gyrus three weeks after lateral fluid percussion injury in male rats. We report here that there is evidence of an ongoing neuroinflammatory response marked by increased neuroinflammatory genes that implicate various neuroinflammatory pathways that are associated with a subset of microglia and astrocyte populations. Full article

Microglia are central to neuroimmune responses and undergo dynamic structural and functional changes in models of stress and addiction, and in response to pharmacological treatments. While transcriptomic and proteomic assays provide insights into molecular profiles, morphological analysis remains a valuable proxy for assessing region-specific microglial response. However, morphological features alone often fail to capture the full complexity of microglial function, underscoring the need for standardized methods and complementary approaches. Here, we describe a standardized imaging pipeline for analyzing microglia in the nucleus accumbens core (NAcore), integrating unbiased confocal image acquisition with precise anatomical reference points. We compare two widely used image analysis platforms—IMARIS and CellSelect-3DMorph—highlighting their workflows, output metrics, and utility in quantifying microglial morphology following treatment with adenosine triphosphate (ATP). Both tools detect well described features of microglial dynamics, though they differ in automation level, analysis speed, and output types. Our findings demonstrate that both platforms provide reliable morphological data, with CellSelect-3DMorph offering a rapid, open-access alternative for high-throughput analysis. Additionally, using software-derived parameters in principal component analysis clustering has proven useful for identifying distinct subpopulations of microglia separated by their morphology. This work provides a practical framework for morphological analysis and promotes reproducibility in microglial studies under environmental and pharmacological interventions. Full article

Intercellular communication in the central nervous system (CNS) is essential for maintaining neural function and coordinating responses to injury or disease. With recent advances in single-cell and spatial transcriptomics, a growing body of research has revealed that this communication is highly dynamic, shifting across states of health, aging, demyelination, and neurodegeneration. In this review, we synthesize the current findings on intercellular communication networks involving neurons, astrocytes, microglia, oligodendrocytes, and other glial populations in the CNS across four major states: healthy homeostasis, aging, demyelinating diseases, and Alzheimer’s disease (AD). We focus on how changes in intercellular communication contribute to the maintenance or disruption of CNS integrity and function. Mechanistic insights into these signaling networks have revealed new molecular targets and pathways that may be exploited for therapeutic intervention. By comparing the intercellular signaling mechanisms across different disease contexts, we underscore the importance of CNS crosstalk not only as a hallmark of disease progression, but also as a potential gateway for precision therapy. Full article

Glioblastoma (GBM) is an aggressive brain tumor characterized by an immunosuppressive tumor microenvironment (TME), which contributes to treatment resistance and disease progression. Background: Tumor-associated macrophages (TAMs), comprising both resident microglia and bone marrow–derived macrophages, play a central role in supporting tumor growth, angiogenesis, and immune evasion. Most TAMs adopt an M2-like immunosuppressive phenotype, making them a promising target for immunomodulatory strategies in GBM. Method: According to PRISMA guidelines, we conducted a systematic literature review and recruited eligible studies focused on therapeutic approaches targeting TAMs in GBM, emphasizing mechanisms of action, efficacy, and challenges. Data extraction focused on therapeutic classes, outcomes, and TAM-related biomarkers. Results: We identified 30 studies meeting the inclusion criteria. These therapies are categorized into three main strategies: inhibition of TAM recruitment, enhancement of TAM-mediated phagocytosis, and reprogramming of TAMs. Combination strategies, including TAM-targeting with checkpoint inhibitors, nanoparticles, and oncolytic viruses, show synergistic effects in preclinical models. Conclusions: Targeting TAMs represents a multifaceted strategy for GBM treatment. Current evidence underscores the need for combination approaches integrating TAM modulation with existing standard-of-care therapies. Clinical translation remains limited due to challenges such as TAM heterogeneity, plasticity, immunosuppressive therapies, and restricted drug delivery across the blood–brain barrier. Future directions should highlight personalized treatments based on detailed TME profiling. Combining TAM-targeted therapies with agents modulating metabolic or immune pathways, and leveraging advanced delivery systems and spatial transcriptomics may improve efficacy. Full article

Background: Severe damage to one side of the brain often leads to adverse consequences and can also cause widespread changes throughout the brain, especially in the contralateral area. Studying molecular changes in the contralateral cerebral hemisphere, especially with regard to genetic regulation, can help discover potential treatment strategies to promote recovery after severe brain trauma on one side. Methods: In our study, the right motor cortex was surgically removed to simulate severe unilateral brain injury, and changes in glial cells and synaptic structure in the contralateral cortex were subsequently assessed through immunohistological, morphological, and Western blot analyses. We conducted transcriptomic studies to explore changes in gene expression levels associated with the inflammatory response. Results: Seven days after corticotomy, levels of reactive astrocytes and hypertrophic microglia increased significantly in the experimental group, while synapsin-1 and PSD-95 levels in the contralateral motor cortex increased. These molecular changes are associated with structural changes, including destruction of dendritic structures and the encapsulation of astrocytes by synapses. Genome-wide transcriptome analysis showed a significant increase in gene pathways involved in inflammatory responses, synaptic activity, and nerve fiber regeneration in the contralateral cortex after corticorectomy. Key transcription factors such as NF-κB1, Rela, STAT3 and Jun were identified as potential regulators of these contralateral changes. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) confirmed that the mRNA expression levels of Cacna1c, Tgfb1 and Slc2a1 genes related to STAT3, JUN, and NF-κB regulation significantly increased in the contralateral cortex of the experimental group. Conclusions: After unilateral brain damage occurs, changes in the contralateral cerebral hemisphere are closely related to processes involving inflammation and synaptic function. Full article

Tuberous sclerosis complex (TSC) is a systemic disease caused by mutations in either the TSC1 (encoding hamartin) or TSC2 (encoding tuberin) gene, with mutations in the TSC2 gene potentially leading to more severe clinical symptoms. Neurological symptoms are a common clinical manifestation of TSC, and neuroinflammation is thought to play an important role. Glial cells are a major source of neuroinflammation, but whether microglia are involved in the activation of the NOD-like receptor protein 3 (NLRP3) inflammasome and the expression of interleukin-1β (IL-1β) in TSC patients remains unclear. We used a transcriptome sequencing dataset for bioinformatics analysis to explore the differences in the expression of microglial inflammasome-associated hub genes. TSC2 knockdown (TSC2 KD) microglia (HMC3 cell line) were generated by lentivirus, and the expression of inflammasome-associated hub genes, microglial activation, and NLRP3 inflammasome activation were verified. In addition, experiments were performed to explore the regulatory effects of rapamycin. Bioinformatics analysis identified a total of eight inflammasome-associated hub genes. By detecting GFP fluorescence, TSC2 mRNA, TSC2 protein expression, and the phosphorylation of the mammalian target of rapamycin (p-mTOR)/mTOR, we confirmed that the TSC2 KD microglia model was successfully established. Compared with the control group, the TSC2 KD group presented higher mRNA levels and fluorescence intensities of microglia AIF1 and CD68, as well as greater reactive oxygen species (ROS) production. Eight inflammasome-associated hub gene mRNA assays revealed that the expression of the NLRP3 and IL1B genes was increased. Compared with the control group, the TSC2 KD group presented increased levels of NLRP3 and Pro-IL-1β proteins in cells and Cleaved-Caspase 1 and Cleaved-IL-1β proteins in the supernatant, suggesting NLRP3 inflammasome activation. Rapamycin intervention alleviated these changes, demonstrating that the TSC2 gene regulation of microglial activation and NLRP3 inflammasome activation are correlated with mTOR phosphorylation. In conclusion, microglia are activated in TSC patients and participate in the NLRP3 inflammasome-associated neuroinflammatory response, and rapamycin treatment can alleviate these changes. Full article

Amyotrophic lateral sclerosis (ALS) is characterized by upper and lower motor neuron failure and poor prognosis. This study performed a meta-analysis of gene expression datasets that compared bulk-processed post-mortem spinal cord from ALS and control (CTL) patients. The analysis included 569 samples (454 ALS, 115 CTL) from 348 individuals (262 ALS, 86 CTL). Patterns of differential expression bias, related to mRNA abundance, gene length and GC content, were discernable from individual studies but attenuated by meta-analysis. A total of 213 differentially expressed genes (DEGs) were identified (144 ALS-increased, 69 ALS-decreased). ALS-increased DEGs were most highly expressed by microglia and associated with MHC class II, immune response and leukocyte activation. ALS-decreased DEGs were abundantly expressed by mature oligodendrocytes (e.g., the MOL5 phenotype) and associated with myelin production, plasma membrane and sterol metabolism. Comparison to spatial transcriptomics data showed that DEGs were prominently expressed in white matter, with increased DEG expression strongest in the ventral/lateral white matter. These results highlight white matter as the spinal cord region most strongly associated with the shifts in mRNA abundance observed in bulk-processed tissues. These shifts can be explained by attrition of mature oligodendrocytes and an ALS-emergent microglia phenotype that is partly shared among neurodegenerative conditions. Full article

Chronic migraine (CM) is a debilitating neurological disorder, yet the glial-specific mechanisms underlying its pathophysiology in the trigeminal nucleus caudalis (TNC)—a critical hub for craniofacial pain processing—remain poorly understood. Here, we employed single-nucleus RNA sequencing (snRNA-seq) to resolve cell-type-specific transcriptional landscapes in a nitroglycerin (NTG)-induced CM rat model, with a particular focus on microglia and astrocytes. We identified 19 transcriptional clusters representing nine major cell types, among which reactive microglia (NTG-Mic) and astrocytes (NTG-Asts) were markedly expanded. The NTG-Mic displayed a glycolysis-dominant, complement-enriched state, whereas the NTG-Asts exhibited concurrent activation of amino acid transport and cytokine signaling pathways. Pseudotime trajectory analysis revealed bifurcated glial activation paths, with NTG driving both cell types toward terminal reactive states. Intercellular communication inference uncovered suppressed homeostatic interactions (e.g., CSF1-CSF1R) alongside enhanced proinflammatory signaling (e.g., FGF1-FGFR2, PTN-SDC4), particularly affecting neuron–glia and glia–glia crosstalk. Together, these findings define a high-resolution atlas of glial reprogramming in CM, implicating state-specific metabolic–immune transitions and dysregulated glial communication as potential targets for therapeutic intervention. Full article

Traumatic brain injury (TBI) in the elderly is frequently associated with worsened neurological outcomes and prolonged recovery, yet the age-specific molecular mechanisms driving this vulnerability remain poorly understood. Aging is characterized by increased oxidative stress and chronic neuro-inflammation, both of which may amplify the brain’s susceptibility to injury. In this study, we identify spermine oxidase (SMOX), a polyamine-catabolizing enzyme that produces reactive oxygen species, as a key mediator linking oxidative stress and neuro-inflammation to age-dependent TBI susceptibility. Using a mouse model of controlled cortical impact (CCI), we found that SMOX expression was significantly upregulated in aged brains, primarily in neurons and microglia, and this increase correlated with greater microglial activation, elevated pro-inflammatory cytokine expression, and widespread neuronal degeneration. Notably, SMOX upregulation also impaired astrocytic glutamate clearance by disrupting the membrane localization of the transporter GLT-1, contributing to excitotoxic stress. Importantly, analysis of postmortem human brain samples and transcriptomic data revealed a parallel age-related increase in SMOX expression, supporting its translational relevance. The pharmacological inhibition of SMOX with JNJ-9350 in aged mice reduced oxidative and inflammatory markers, preserved neuronal viability, and improved motor, cognitive, and emotional outcomes up to 30 days post-injury. These findings establish SMOX as a critical molecular driver of age-related vulnerability to TBI and highlight its inhibition as a promising therapeutic strategy for improving outcomes in elderly TBI patients. Full article

Background/Objectives: X-inactive-specific transcript (XIST) is a factor that plays a role in neuroinflammation. This study investigated the role of XIST in neuronal development, neuroinflammation, myelination, and therapeutic responses within cerebral organoids in the context of Multiple Sclerosis (MS) pathogenesis. Methods: Human cerebral organoids with oligodendrocytes were produced from XIST-silenced H9 cells, and the mature organoids were subsequently treated with either FTY720 or DMF. Gene expression related to inflammation and myelination was subsequently analyzed via qRT-PCR. Immunofluorescence staining was used to assess the expression of proteins related to inflammation, myelination, and neuronal differentiation. Alpha-synuclein protein levels were also checked via ELISA. Finally, transcriptome analysis was conducted on the organoid samples. Results: XIST-silenced organoids presented a 2-fold increase in the expression of neuronal stem cells, excitatory neurons, microglia, and mature oligodendrocyte markers. In addition, XIST silencing increased IL-10 mRNA expression by 2-fold and MBP and PLP1 expression by 2.3- and 0.6-fold, respectively. Although XIST silencing tripled IBA1 protein expression, it did not affect organoid MBP expression. FTY720, but not DMF, distinguished MBP and IBA1 expression in XIST-silenced organoids. Furthermore, XIST silencing reduced the concentration of alpha-synuclein from 300 to 100 pg/mL, confirming its anti-inflammatory role. Transcriptomic and gene enrichment analyses revealed that the differentially expressed genes are involved in neural development and immune processes, suggesting the role of XIST in neuroinflammation. The silencing of XIST modified the expression of genes associated with inflammation, myelination, and neuronal growth in cerebral organoids, indicating a potential involvement in the pathogenesis of MS. Conclusions: XIST may contribute to the MS pathogenesis as well as neuroinflammatory diseases such as and Alzheimer’s and Parkinson’s diseases and may be a promising therapeutic target. Full article

A search of the PubMed database for publications on microglia reveals an intriguing shift in scientific interest over time. Dividing microglia into categories such as “resting” and “activated” or M1 versus M2 is nowadays obsolete, with the current research focusing on unraveling microglial heterogeneity. The onset of transcriptomics, especially single-cell RNA sequencing (scRNA-seq), has profoundly reshaped our understanding of microglia heterogeneity. Conversely, microglia morphology analysis can offer important insights regarding their activation state or involvement in tissue responses. This review explores microglial heterogeneity under homeostatic conditions, developmental stages, and disease states, with a focus on integrating transcriptomic data with morphological analysis. Beyond the core gene expression profile, regional differences are observed with cerebellar microglia exhibiting a uniquely immune-vigilant profile. During development, microglia express homeostatic genes before birth, yet the bushy appearance is a characteristic that appears later on. In neurodegeneration, microglia alternate between proinflammatory and neuroprotective roles, influenced by regional factors and disease onset. Understanding these structural adaptations may help identify specific microglial subpopulations for targeted therapeutic strategies. Full article

In previous studies, we isolated a series of novel gentisides with nerve growth factor (NGF)-mimic activities from Gentiana rigescens Franch and conducted continuous structure–activity relationship (SAR) studies. Recently, a lead compound named TBG096 was discovered with significant NGF-mimic activity, low toxicity, and ability to pass through the blood–brain barrier (BBB). At the cell level, TBG096 exerts NGF-mimic activity by regulation of heat-shock cognate protein 70 (Hsc70) and downstream proteins. Subsequently, high-fat diet (HFD)-induced Alzheimer disease (AD) mouse models were used to evaluate the anti-AD efficacy of the compound. TBG096 significantly improved the memory dysfunction of AD mice at doses of 0.1, 5, and 20 mg/kg, respectively. In order to elucidate the mechanism of action of the compound against AD, the RNA-sequence analysis of transcriptomics, quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence staining, and Western blot analysis were performed using animal samples. TBG096 significantly increased the expression of the Wnt gene family (Wnt10b, Wnt5a, and Wnt1) and the number of mature neurons and newborn neurons in the hippocampus and cerebral cortex of AD mice, respectively. At the same time, it reduced the activity of microglia, astrocyte cells, and expression of inducible nitric oxide synthase (INOS) in the brain. Moreover, this compound significantly increased phosphorylated-adenosine 5′-monophosphate-activated protein kinase (AMPK), Hsc70, and lysosomal-associated membrane protein 2a (LAMP2A) and decreased the expression of hexokinase 2 (HK2), pyruvate kinase M2 (PKM2), amyloid precursor protein (APP), microtubule-associated protein tau (Tau), phosphoryl-Tau, and β-amyloid (Aβ) at the protein level. These results suggest that TBG096 produced the NGF-mimic activity and the anti-AD effect via promoting neurogenesis and modification of the Hsc70/HK2/PKM2/LAMP2A signaling pathway, proposing a potential novel approach to counteracting cognitive decline by developing small molecules that promote neurogenesis and the Hsc70 signaling pathway. Full article

Spinocerebellar ataxia type 1 (SCA1) is a rare autosomal dominant inherited neurodegenerative disease caused by the expansion of glutamine (Q)-encoding CAG repeats in the gene ATAXIN1 (ATXN1). Patients with SCA1 suffer from movement and cognitive deficits and severe cerebellar pathology. Previous studies identified sex differences in disease progression in SCA1 patients, but whether these differences are present in mouse models is unclear. Using a battery of behavioral tests, immunohistochemistry of brain slices, and RNA sequencing, we examined sex differences in motor and cognitive performance, cerebellar pathology, and cerebellar gene expression changes in a recently created conditional knock-in mouse model f-ATXN1^146Q expressing human coding regions of ATXN1 with 146 CAG repeats. We found worse motor performance and weight loss accompanied by increased microglial activation and an increase in immune viral response pathways in male f-ATXN1^146Q mice. Full article

Alzheimer’s disease (AD) is an increasing global healthcare crisis with few effective treatments. The accumulation of amyloid plaques and hyper-phosphorylated tau are thought to underlie the pathogenesis of AD. However, current studies have recognized a prominent role of cerebrovascular dysfunction in AD. We recently reported that SNPs in soluble epoxide hydrolase (sEH) are linked to AD in human genetic studies and that long-term administration of an sEH inhibitor attenuated cerebral vascular and cognitive dysfunction in a rat model of AD. However, the mechanisms linking changes in cerebral vascular function and neuroprotective actions of sEH inhibitors in AD remain to be determined. This study investigated the effects of administration of an sEH inhibitor, 1-(1-Propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl]urea (TPPU), on neurovascular coupling, blood–brain barrier (BBB) function, neuroinflammation, and cognitive dysfunction in an hAPP/PS1 TgF344-AD rat model of AD. We observed predominant β-amyloid accumulation in the brains of 9–10-month-old AD rats and that TPPU treatment for three months reduced amyloid burden. The functional hyperemic response to whisker stimulation was attenuated in AD rats, and TPPU normalized the response. The sEH inhibitor, TPPU, mitigated capillary rarefaction, BBB leakage, and activation of astrocytes and microglia in AD rats. TPPU increased the expression of pre- and post-synaptic proteins and reduced loss of hippocampal neurons and cognitive impairments in the AD rats, which was confirmed in a transcriptome and GO analysis. These results suggest that sEH inhibitors could be a novel therapeutic strategy for AD. Full article