bims-microg 2025-10-26 papers

bims-microg

Biomed News

on Microglia in health and disease

Issue of 2025–10–26
twenty papers selected by
Marcus Karlstetter, Universität zu Köln

Transcriptional and epigenetic targets of MEF2C in human microglia contribute to cellular functions related to autism risk and age-related disease.
Microglial MEF2C is a uniquely human bridge between neurodevelopment and neurodegeneration.
The gain-of-function TREM2-T96K mutation increases risk for Alzheimer's disease by impairing microglial function.
Microglial Deletion of Hrh4 Alleviates Alzheimer's Disease Pathologies by Enhancing Microglial Phagocytosis of Amyloid-β and Tau.
Microglial Feimin Alleviates Cognitive Impairment in High-Fat Diet-Fed Mice.
The chloride intracellular channel 1 (CLIC1) is essential for microglial morphodynamics and neuroinflammation.
Stress induces behavioral disorders by promoting microglial phagocytosis via decreasing neuronal Dkk3.
Captopril restores microglial homeostasis and reverses ASD-like phenotype in a model of ASD induced by exposure in utero to anti-caspr2 IgG.
Amyloid precursor protein and C99 are subunits in human microglial Hv1 channels that enhance current and inflammatory mediator release.
Minocycline inhibits microglial activation and mitigates compulsive and anxiety-like behaviors induced by a high-refined carbohydrate diet in male BALB/c mice.
AIstain: Enhancing microglial phagocytosis analysis through deep learning.
Mu opioid receptor activation in microglia enhances HIV-1 infection and HIV-infection-induced inflammatory responses.
3KO-NSCs ameliorate behavioral deficits and modulate gut microbiota in a VPA-induced C57BL/6 mouse model of autism.
Electroacupuncture ameliorates Autism Spectrum Disorder via modulating the gut-brain axis depending on the integrity of vagus nerve.
Microglia-containing neural organoids as brain microphysiological systems for long-term culture.
Multiomics Data Reveal Microglia's Promotion for Choroidal Neovascularization in Age-related Macular Degeneration.
FLVCR1 Deficiency Impairs Mitochondrial Homeostasis in Retinal Degeneration: Choline as a Potential Therapy.
Acupuncture Improves Depression-Like Behaviors in Rats Through Gut Microbiota and TLR4/MyD88/NF-κB Pathway Modulation.
Protocol for generating a human iPSC-derived tri-culture model to study interactions between neurons, astrocytes, and microglia.
Flow Cytometry and Single-Cell Analysis for Characterizing Microglia Activation in Early Postnatal Mouse Brain Development.

Nat Immunol. 2025 Oct 22.

Transcriptional and epigenetic targets of MEF2C in human microglia contribute to cellular functions related to autism risk and age-related disease.

Celina Nguyen, Emily H Broersma, Anna S Warden, Cristina Mora, Claudia Z Han, Zahara Keulen, Nathanael Spann, Jing Wang, Gabriela Ramirez, Samantha Mak, Samantha Trescott, Mohammadparsa Khakpour, Avalon Johnson, Fatir Qureshi, Michael R La Frano, Kiana Mohajeri, Michael E Talkowski, Olivia Corradin, Marie-Ève Tremblay, Christopher K Glass, Nicole G Coufal.

MEF2C encodes a transcription factor that is critical in nervous system development. Here, to examine disease-associated functions of MEF2C in human microglia, we profiled microglia differentiated from isogenic MEF2C-haploinsufficient and MEF2C-knockout induced pluripotent stem cell lines. Complementary transcriptomic and functional analyses revealed that loss of MEF2C led to a hyperinflammatory phenotype with broad phagocytic impairment, lipid accumulation, lysosomal dysfunction and elevated basal inflammatory cytokine secretion. Genome-wide profiling of MEF2C-bound sites coupled with the active regulatory landscape enabled inference of its transcriptional functions and potential mechanisms for MEF2C-associated cellular functions. Transcriptomic and epigenetic approaches identified substantial overlap with idiopathic autism datasets, suggesting a broader role of human microglial MEF2C dysregulation in idiopathic autism. In a mouse xenotransplantation model, loss of MEF2C led to morphological, lysosomal and lipid abnormalities in human microglia in vivo. Together, these studies reveal mechanisms by which reduced microglial MEF2C could contribute to the development of neurological diseases.

DOI: https://doi.org/10.1038/s41590-025-02299-0
Nat Immunol. 2025 Oct 22.

Microglial MEF2C is a uniquely human bridge between neurodevelopment and neurodegeneration.

Ryan J Rahman, Mariko L Bennett.

DOI: https://doi.org/10.1038/s41590-025-02313-5
Neuron. 2025 Oct 17. pii: S0896-6273(25)00745-7. [Epub ahead of print]

The gain-of-function TREM2-T96K mutation increases risk for Alzheimer's disease by impairing microglial function.

Alzheimer’s Disease Neuroimaging Initiative (ADNI)

  We previously reported that T96K is a gain-of-function mutation in TREM2 based on its ability to increase ligand-dependent activation. Here, we show that TREM2T96K increases risk for Alzheimer's disease (AD) in a whole-genome sequencing dataset comprised of family-based and case-control samples. Trem2T96K also reduced clustering of microglia around β-amyloid (Aβ) plaques exclusively in female 5xFAD mice. Furthermore, T96K decreased levels of soluble Trem2 in female 5xFAD mice and human microglial cell cultures. We also observed impaired uptake of Aβ in Trem2T96K knockin microglial cells. Moreover, Trem2T96K reduced total area of phagocytic microglia, specifically in female 5xFAD mice. Single-cell RNA sequencing (scRNA-seq) profiling of microglia revealed that Trem2T96K impairs the transition of homeostatic microglia into disease-associated microglia (DAM) in female 5xFAD mice. Downregulated inflammatory pathways associated with Trem2T96K included interleukin (IL)-6/JAK/STAT3, complement, and interferon (IFN)-γ response. Collectively, our results indicate that, like the loss-of-function mutation R47H, Trem2T96K adversely affects microglial function in a sex-dependent manner.

Keywords:  Alzheimer’s; T96K; TREM2; amyloid; gain of function; innate immunity; microglia; neuroinflammation; single-cell RNA-seq; uptake

DOI:  https://doi.org/10.1016/j.neuron.2025.09.032
Adv Sci (Weinh). 2025 Oct 24. e05421

Microglial Deletion of Hrh4 Alleviates Alzheimer's Disease Pathologies by Enhancing Microglial Phagocytosis of Amyloid-β and Tau.

Yi-Jun Xu, Tan Wu, Larry Tso-Lun Lo, Chi-Chiu Ko, Xin Wang, Chi Him Eddie Ma.

  Amyloid-beta (Aβ) and hyperphosphorylated tau (p-tau) aggregation are hallmark pathogenic events in Alzheimer's disease (AD). Microglial clearance of these toxic aggregates is essential, yet the underlying mechanisms remain poorly understood. This study demonstrates that low-dose ionizing radiation (LDIR) provides protection against Aβ toxicity in vitro and rescues cognitive deficits in sporadic, young, and aged familial AD mouse models, including reductions in Aβ plaque, tauopathy, and microgliosis, while promoting microglial phagocytosis in aged 3xTg-AD mice. Transcriptomic analysis identifies VUF6002, a histamine H4 receptor (H4R) antagonist, which mimics the beneficial effects of LDIR by promoting microglial activity. VUF6002 treatment restores cognitive function in aged 3xTg-AD and APPswe/PSEN1dE9 mice and significantly increases Aβ and p-tau clearance by resident microglia. Mechanistically, deletion of Hrh4 in microglia, but not in neurons, reverses cognitive deficits and mitigates key AD pathogenesis by activating the cAMP/TGF-β1/Smad3 pathway. These beneficial effects are completely abolished by inhibition of TGF-β receptor 1 signaling, which is also downregulated in AD patients. Collectively, these findings reveal a H4R/cAMP/TGF-β1/Smad3 signaling axis involved in microglial phagocytosis and cognitive function, serving as a novel therapeutic target for AD.

Keywords:  Alzheimer's disease; VUF6002; cAMP/TGF‐β1/Smad3; histamine receptor; in silico small‐molecule bioinformatics analysis; low‐dose ionizing radiation; microglial phagocytosis

DOI:  https://doi.org/10.1002/advs.202505421
Adv Sci (Weinh). 2025 Oct 20. e12023

Microglial Feimin Alleviates Cognitive Impairment in High-Fat Diet-Fed Mice.

Ran Gao, Zhonghua Xiong, Wenting Su, Jiahui Deng, Bin Zhai, Gaizhi Zhu, Min Zhang, Qi Zeng, Jinming Qiu, Ziqing Bian, He Xiao, Guoming Luan, Renxi Wang.

  Lipid droplet accumulation in microglia, microglia-mediated neuroinflammation, and subsequent neuronal damage are hallmark features of high-fat diet (HFD)-induced cognitive impairment. In this analysis, this is proposed that a new molecule feimin (B230219D22Rik in mice) is a key negative regulator of LD accumulation and the inflammatory response in HFD-induced cognitive impairment. To test this hypothesis, BV2 microglia is exposed to palmitic acid (PA) in vitro, mimicking the effects of an HFD. This is found that feimin expression is significantly increased following high-lipid stimulation. Feimin-specific knockdown in BV2 cells led to enhanced LD accumulation, exacerbated inflammatory responses and neuronal apoptosis, whereas feimin overexpression has the opposite effect. Mechanistically, immunoprecipitation (IP) assays revealed that an interaction between feimin and AKT suppressed the AKT-mTOR signaling pathway. To further investigate the role of feimin in vivo, microglial feimin-conditional knockout mice (feiminMic-/-) is developed. In the HFD model, feiminMic-/- mice exhibited increased LD accumulation in hippocampal microglia, enhanced inflammation, and neuronal apoptosis, resulting in significant cognitive decline. In conclusion, this findings identified feimin as a key negative regulator of HFD-induced LD accumulation and the microglia-mediated inflammation response, suggesting that it is an attractive therapeutic target for cognitive decline associated with HFDs.

Keywords:  B230219D22Rik; BV2; Feimin; High‐fat diets; Hippocampus; Lipid droplets; Neuroinflammation; Palmitic acid

DOI:  https://doi.org/10.1002/advs.202512023
Sci Adv. 2025 Oct 24. 11(43): eads9181

The chloride intracellular channel 1 (CLIC1) is essential for microglial morphodynamics and neuroinflammation.

Ali Rifat, Tom Bickel, Patricia Kreis, Thorsten Trimbuch, Julia Onken, Andranik Ivanov, Giulia Albertini, Dieter Beule, Michele Mazzanti, Harpreet Singh, Britta J Eickholt, Bart De Strooper, Jörg R P Geiger, Christian Madry.

Microglial functions rely on their morphodynamic versatility and inflammatory response, yet the molecular determinants, particularly ion channels and receptors, remain poorly understood. Here, we identify chloride intracellular channel 1 (CLIC1), a protein known to exist in both soluble and membrane-associated forms, as highly enriched in human and murine microglia, with minimal expression in other brain cells. Acute blockade or genetic deletion of CLIC1 markedly attenuates microglial surveillance by reducing ramification and motility, without affecting chemotaxis. This phenotype is recapitulated in xenografted human microglia and human brain tissue. Mechanistically, CLIC1 effects involve interactions with actin-binding ezrin, radixin, and moesin (ERM) proteins, suggesting a role in linking the plasma membrane to the cytoskeleton. Contrary to its name, CLIC1 functions are chloride-independent and thus unlikely to reflect ion channel activity. This is supported by patch-clamp electrophysiology revealing lack of chloride conductance in surveillant microglia. Following ATP-evoked activation, CLIC1 blockade strongly suppresses NLRP3-dependent interleukin-1β release, suggesting therapeutic potential against neuroinflammation.

DOI: https://doi.org/10.1126/sciadv.ads9181
Mol Psychiatry. 2025 Oct 24.

Stress induces behavioral disorders by promoting microglial phagocytosis via decreasing neuronal Dkk3.

Xiao Chen, Kaiqi Zhang, Ye Li, Changmin Wang, Haiyan Lou, Shuyan Yu.

Microglia play an important role in the central nervous system, particularly with regard to altering synaptic function. However, the exact function of these microglia in major depressive disorder (MDD) remains unclear. Here, we report that in a chronic unpredictable mild stress (CUMS) model of depression, the expression of Dkk3 protein, the dickkopf Wnt signaling pathway inhibitor 3, was downregulated in the cornu ammonis 1 (CA1) region of the hippocampus. Neuronal-specific knockdown of Dkk3 increased microglial activation and engulfment, thereby contributing to depressive- and anxiety-like behaviors, via the Wnt-CX3CL1/CX3CR1 signaling pathway. With the ablation of microglia or chemical inhibition of CA1 pyramidal neurons, depressive-like behaviors were abolished. Moreover, treatment with a CX3CL1 McAb or XAV-939, an inhibitor of the Wnt pathway, ameliorated CUMS-induced behavioral deficits and decreased microglial phagocytosis of neuronal spines. Taken together, these results demonstrate that Dkk3 plays a critical role in regulating microglial engulfment, an effect which induces long-lasting disruptions of CA1 neurons in response to stress. These findings reveal important new mechanistic insights into the potential for Dkk3 to exert a protective role against MDD pathogenesis.

DOI: https://doi.org/10.1038/s41380-025-03314-4
Mol Psychiatry. 2025 Oct 23.

Captopril restores microglial homeostasis and reverses ASD-like phenotype in a model of ASD induced by exposure in utero to anti-caspr2 IgG.

Benjamin Spielman, Ciara Bagnall-Moreau, Frank Chen, Crystal Balvuena, Christian Cruz, Joseph Carrion, An Vo, Arnon Arazi, Lior Brimberg.

Microglia play a crucial role in brain development, including synaptic pruning and neuronal circuit formation. Prenatal disruptions, such as exposure to maternal autoantibodies, can dysregulate microglial function and contribute to neurodevelopmental disorders like autism spectrum disorder (ASD). Maternal antibodies targeting the brain protein Caspr2, encoded by ASD risk gene Cntnap2, are found in a subset of mothers of children with ASD. In utero exposure to these antibodies in mice leads to an ASD-like phenotype in male but not in female mice, characterized by altered hippocampal microglial reactivity, reduced dendritic spine density, and impaired social behavior. Here, we studied the role of microglia in mediating the effect of in utero exposure to maternal anti-Caspr2 antibodies and whether we can ameliorate this phenotype. In this study we demonstrate that microglial reactivity emerges early in postnatal development and persists into adulthood following exposure in utero to maternal anti-Caspr2 IgG. Captopril, a blood-brain barrier permeable angiotensin-converting enzyme (ACE) inhibitor, but not enalapril (a non-BBB permeable ACE inhibitor) ameliorates these deficits. Captopril treatment reversed microglial activation, restored spine density and dendritic arborization in CA1 hippocampal pyramidal neurons, and improved social interaction. Single-cell RNA sequencing of hippocampal microglia identified a captopril-responsive subcluster exhibiting downregulated translation (eIF2 signaling) and metabolic pathways (mTOR and oxidative phosphorylation) in mice exposed in utero to anti-Caspr2 antibodies treated with saline compared to saline-treated controls. Captopril reversed these transcriptional alterations, restoring microglial homeostasis. Our findings suggest that exposure in utero to maternal anti-Caspr2 antibodies induces sustained neuronal alterations, microglial reactivity, and metabolic dysfunction, contributing to the social deficits in male offspring. BBB-permeable ACE inhibitors, such as captopril, warrant further investigation as a potential therapeutic strategy in a subset of ASD cases associated with microglial reactivity.

DOI: https://doi.org/10.1038/s41380-025-03298-1
Proc Natl Acad Sci U S A. 2025 Oct 28. 122(43): e2509903122

Amyloid precursor protein and C99 are subunits in human microglial Hv1 channels that enhance current and inflammatory mediator release.

Ruiming Zhao, Punyanuch Sophanpanichkul, Jean Paul Chadarevian, Yiwen Ding, Hui Dai, Maha Nayak, Hayk Davtyan, Mathew Blurton-Jones, Steve A N Goldstein.

  In Alzheimer's disease (AD), hyperactivated microglia produce inflammatory mediators that contribute to neuroinflammation and neuronal damage. Amyloid precursor protein (APP), a transmembrane protein expressed in many cell types, including neurons and microglia, plays a critical role in AD pathogenesis via its secretase-mediated processing to release the C-terminal 99-residue transmembrane fragment (C99) that is further cleaved to yield amyloid-β peptides. Voltage-gated proton channels (Hv1) have been implicated in microglial activation and release of inflammatory mediators, but the potential role of these channels in human microglia and AD pathogenesis remains unclear. Here, we demonstrate that human induced pluripotent stem cell-derived microglia (iMG) express native Hv1 channels with biophysical and pharmacological attributes determined by their coassembly with APP and that APP knockdown decreases Hv1 currents, suppressing cytokine and reactive oxygen species release. In HEK293T cells, APP is shown to increase current by favoring channel opening at more negative membrane potentials. C99 is sufficient to assemble with Hv1 and alters channel function even more significantly than APP. Coimmunoprecipitation, total internal reflection fluorescence microscopy, and altered pharmacology further demonstrate that C99 forms stable complexes with Hv1 in the plasma membrane. In addition, we find that two early-onset AD mutations in APP (E682K and D694N) that reside within C99 significantly increase voltage-dependent channel activity beyond that induced by wild type C99, rationalizing their enhanced mediation of neuroinflammation.

Keywords:  APP; Alzheimer’s disease; C99; Hv1; voltage-gated proton channel

DOI:  https://doi.org/10.1073/pnas.2509903122
Metab Brain Dis. 2025 Oct 21. 40(8): 294

Minocycline inhibits microglial activation and mitigates compulsive and anxiety-like behaviors induced by a high-refined carbohydrate diet in male BALB/c mice.

Nícia Pedreira Soares, Anna Paula Marçal, Amanda Carla Oliveira, Rayssa C Briânis, Rafaela Pinto Coelho Santos, Adaliene Verssiani Matos Ferreira, Daniele Cristina de Aguiar.

  Consumption of a high-carbohydrate (HC) diet, which is commonly associated with obesity, has been linked to anxiety-like and compulsive behaviors. This association is predominantly attributed to chronic low-grade inflammation, which affects both the peripheral tissues and the central nervous system. Microglial cells, which are essential for neuroinflammation, exacerbate psychiatric disorders, such as depression and anxiety. Minocycline, a second-generation tetracycline antibiotic, exhibits anti-inflammatory and neuroprotective properties by modulating the activation of microglia. This study aimed to investigate whether minocycline alleviates compulsive and anxiety-like behaviors, as well as inflammatory responses, in mice fed an HC diet. Male BALB/c mice were fed standard chow (control diet) or high-carbohydrate (HC) diet for 12 weeks. Minocycline (50 mg/kg) was administered for 7 days (intraperitoneally) or 15 days (orally, by gavage) before the end of the dietary protocol. Behavioral assessments using the Marble Burying (MB) and novelty suppressed feeding (NSF) tests were conducted 24 h after the end of the diet. Brain, adipose tissue, and serum samples were analyzed for morphological and biochemical changes. Minocycline treatment for 15 days, but not for 7 days, reversed compulsive and anxiety-like behaviors. It also reduced microglial activation in the prefrontal cortex and the hippocampus. Despite these central effects, minocycline showed a limited influence on the peripheral metabolic parameters altered by the HC diet. This study highlights the role of microglial cells in HC diet-related behavioral changes in male mice and indicates that minocycline exerts central anti-inflammatory effects. These findings warrant further studies to confirm their relevance in other animal models and their potential applicability to anxiety and obsessive-compulsive disorders in humans.

Keywords:  Anxiety; Compulsive behavior; High-carbohydrate diet; Minocycline and mice; Obesity

DOI:  https://doi.org/10.1007/s11011-025-01731-6
Cell Rep Methods. 2025 Oct 17. pii: S2667-2375(25)00243-7. [Epub ahead of print] 101207

AIstain: Enhancing microglial phagocytosis analysis through deep learning.

Alexander Zähringer, Janaki Manoja Vinnakota, Tobias Wertheimer, Philipp Saalfrank, Marie Follo, Florian Ingelfinger, Robert Zeiser.

  Investigating microglial phagocytosis is essential for understanding the mechanisms underlying brain health and disease. Dysregulation of phagocytosis is implicated in various neurological disorders, necessitating accurate analysis. Leveraging advances in deep learning, this study explores the application of a U-Net-based neural network for image cytometry to enhance the analysis of microglial phagocytosis. Murine microglia were imaged using the Olympus ScanR system, generating a substantial dataset for training a U-Net. The U-Net (AIstain) demonstrated superior performance in cell detection compared to live cell staining and the established segmentation tools SAM2 and Cellpose 3. Additionally, the model's applicability can be extended to other cell types, including leukemia and breast cancer cells, highlighting its versatility. AIstain provides a straightforward approach for the analysis of live cell images and microglial phagocytosis. This method enhances the precision of the results while simultaneously reducing the complexity of the experiment, thus facilitating substantial progress in the domain of neurobiological research.

Keywords:  CP: computational biology; U-Net; artificial intelligence; microglia; neural network; neuroinflammation; phagocytosis

DOI:  https://doi.org/10.1016/j.crmeth.2025.101207
Front Immunol. 2025 ;16 1628872

Mu opioid receptor activation in microglia enhances HIV-1 infection and HIV-infection-induced inflammatory responses.

Chelsey Skeete, Gabriel Sgambettera, Aldana D Gojanovich, Xianbao He, Daniel Bryant, Mengwei Yang, Shreya Banerjee, Andrés A Quiñones-Molina, Hisashi Akiyama, Gustavo Mostoslavsky, Andrew J Henderson, Suryaram Gummuluru.

  People living with HIV-1 (PWH) and chronically using opioids have elevated risks of developing HIV-associated neurological disorders (HAND) that are often correlated with persistent inflammation. Microglia, innate immune cells in the brain, are the principal HIV-1 reservoir in the central nervous system and regulate neuroinflammation. Our group previously showed that HIV-1 infection of induced pluripotent stem cell (iPSC)-derived microglia and viral intron-containing RNA (icRNA) expression triggers inflammatory responses. Microglia express μ opioid receptor, MOR, yet the immunomodulatory effects of opioids on HIV-1 infection in microglia are unclear. Here, we report that MOR activation impacts HIV-1 infection establishment and HIV-1-induced innate responses in microglia. Morphine pretreatment enhanced reverse transcription (RT), integration, viral transcription, and p24Gag secretion in HIV-1-infected iPSC-derived microglia, which was blocked by treatment with naloxone, a MOR antagonist. In contrast, morphine treatment did not impact HIV-1 infection in MOR-deficient monocyte-derived macrophages, although, induced exogenous expression of MOR in macrophages conferred morphine-mediated enhancement of HIV-1 infection. Interestingly, viral transcriptome analysis by digital-drop PCR revealed selective enhancement of HIV-1 icRNA expression in morphine-exposed iPSC-derived microglia, which correlated with enhanced HIV-1 icRNA-induced secretion of IP-10 in MOR+ cells. Further, PI3K inhibitor, wortmannin, blocked morphine-mediated enhancement of HIV-1 replication and HIV-1 icRNA-induced IP-10 secretion, suggesting that MOR signaling and HIV-1 icRNA expression synergistically activate the PI3K-Akt signaling pathway in microglia to exacerbate virus-induced inflammatory responses.

Keywords:  HIV-1; inflammation; microglia; opioids; µ-opioid receptor

DOI:  https://doi.org/10.3389/fimmu.2025.1628872
Front Immunol. 2025 ;16 1680179

3KO-NSCs ameliorate behavioral deficits and modulate gut microbiota in a VPA-induced C57BL/6 mouse model of autism.

Caixia Wu, Xianjie Li, Han Wang, Xiaoya Yang, Zhaoming Liu.

   Background: Autism spectrum disorder (ASD) involves complex neurological and gastrointestinal pathophysiology. Existing therapies rarely address the gut-brain axis connection. This study evaluated the therapeutic potential of immune-evasive human induced pluripotent stem cell-derived neural stem cells (3KO-NSCs) in a mouse model of ASD.
Methods: We used a valproic acid (VPA)-induced ASD model in C57BL/6 mice. Mice received systemic administration of 3KO-NSCs. Assessments included behavioral assays (social interaction, repetitive behaviors), hippocampal cytokine profiling (IL-6, TNF-α), 16S rRNA sequencing for gut microbiota analysis, immunohistochemistry (Iba1+ microglia), and ultrastructural synaptic analysis.
Results: 3KO-hiPSC-NSC treatment significantly ameliorated VPA-induced ASD-like behaviors. It reduced hippocampal neuroinflammation (decreased IL-6 and TNF-α) and attenuated microglial overactivation (reduced Iba1+ cells), correcting synaptic pruning abnormalities. Concurrently, treatment restored gut microbiota diversity (increased Shannon index), enriching Bacteroides and reducing pro-inflammatory Proteobacteria.
Conclusions: 3KO-NSCs exert dual therapeutic effects by mitigating central neuroinflammation and rebalancing gut microbiota. This provides the first direct evidence that stem cell therapy can modulate the gut-brain axis to treat ASD, positioning 3KO-NSCs as a novel bifunctional therapeutic strategy.

Keywords:  3KO-NSCs; VPA; autism spectrum disorder (ASD); microbiota dysbiosis; neuroinflammation

DOI:  https://doi.org/10.3389/fimmu.2025.1680179
Transl Psychiatry. 2025 Oct 24. 15(1): 428

Electroacupuncture ameliorates Autism Spectrum Disorder via modulating the gut-brain axis depending on the integrity of vagus nerve.

Dong Chen, Xinyi Yang, Daiyan Jiao, Xiaoyan Chen, Wenhui Xiao, Jingjing Zheng, Ying Xin Li, Chao Bao, Yancai Li, Bin Xu, Mengqian Yuan.

Autism spectrum disorder (ASD) is a neurodevelopmental disease characterized by behavioral and neurological abnormalities. Numerous pieces of evidence indicate a strong association between ASD and neuroinflammation mediated by gut microbiota and microglial activation. Previous studies have shown that the therapeutic effects of an acupuncture protocol targeting the bacteria-gut-brain axis in a well-established ASD mouse model induced by prenatal exposure to valproic acid (VPA). We demonstrated that electroacupuncture significantly alleviates behavioral symptoms in VPA model. However, the precise mechanisms remain insufficiently elucidated. In this study, we confirmed that electroacupuncture markedly improved behavioral symptoms in ASD mice. We conducted gut microbiota transplantation from electroacupuncture-treated mice to untreated ASD mice, improving behavioral outcomes in untreated ASD mice. Conversely, by transplanting gut microbiota from ASD mice into electroacupuncture-treated mice, we successfully mitigated the beneficial behavioral effects of acupuncture. We analyzed inflammatory markers in the microglial activation from cerebral cortex and hippocampus tissues, revealing that acupuncture exerts robust anti-neuroinflammatory effects in ASD mice. To further validate the mechanism, we performed vagotomy in ASD mice, which abolished the therapeutic benefits of acupuncture. Our findings establish that the behavioral improvements observed in ASD mice are intricately linked to the diversity and abundance of gut microbiota. Furthermore, regulatory effects of electroacupuncture on ASD behaviors are mediated via bacteria-gut-brain axis, dependent on intact vagus nerve signaling. This study provides compelling evidence for the potential of acupuncture to modulate central neuroinflammation through vagus nerve-mediated gut microbiota regulation, offering novel avenue into its therapeutic application for neurodevelopmental disorders such as ASD.

DOI: https://doi.org/10.1038/s41398-025-03637-4
Front Cell Neurosci. 2025 ;19 1616470

Microglia-containing neural organoids as brain microphysiological systems for long-term culture.

Alex Rittenhouse, Caroline Krall, Jesse Plotkin, Dowlette-Mary Alam El Din, Breanne Kincaid, Jason Laird, Lena Smirnova.

  Microglia, essential for brain development, homeostasis, and neuroinflammation, originate from the yolk sac during embryogenesis and migrate into the developing brain. Because of this developmental origin, many brain organoid models naturally lack microglia and require co-culture. To address this issue, we developed a microglia-integrated brain organoid model (immune-competent brain microphysiological system, μbMPS) by aggregating hiPSC-derived neural and microglia progenitors in U-bottom 96-well plates, allowing controlled and reproducible incorporation of microglia progenitors. We demonstrated that microglia integrated, matured, and survived long-term in the neural environment without the need for costly exogenous microglia-specific growth factors or cytokines. We maintained microglia-containing organoids for over 9 weeks, demonstrating functional activity, phagocytosis, and neuroinflammatory responses. The μbMPS also exhibited enhanced neuronal activity and maturity, providing a scalable, reproducible model for neurodevelopment, disease modeling, and neurotoxicology research.

Keywords:  iPSC-derived 3D models; microglia; microphysiological systems (MPS); neural organoids; new approach methodologies (NAMs)

DOI:  https://doi.org/10.3389/fncel.2025.1616470
Exp Eye Res. 2025 Oct 21. pii: S0014-4835(25)00474-9. [Epub ahead of print] 110701

Multiomics Data Reveal Microglia's Promotion for Choroidal Neovascularization in Age-related Macular Degeneration.

He-Yan Li, Li Dong, Lei Shao, Wen-Bin Wei.

  Age-related macular degeneration (AMD) stands as one of the leading causes of blindness worldwide, driven by the dysregulation of key signaling pathways, including vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β). This study aimed to elucidate the specific cell types within the retina and retinal pigment epithelium (RPE)/choroid complex that contribute to AMD progression, as well as to explore how the expression levels of cysteine-rich protein 2 (CSRP2), a downstream effector, are altered in the pathological mechanisms underlying AMD. By investigating these molecular and cellular dynamics, we seek to provide deeper insights into the disease's progression and identify potential therapeutic targets. Retinal tissues, RPE/choroid complexes, and blood samples from both AMD patients and healthy controls were obtained from the GEO database for differential gene expression analysis. Integrated analysis of tissue and blood samples from AMD patients and healthy controls identified CSRP2 as a critical biomarker gene associated with pathogenesis. To uncover potential underlying mechanisms, we conducted immune infiltration analysis and further validated our findings using single-cell RNA sequencing (scRNA-seq) data from the GEO database. Additionally, scRNA-seq data were utilized to investigate cell-cell communication networks and perform Gene Set Enrichment Analysis (GSEA). scRNA-seq analysis demonstrated that CSRP2 was significantly upregulated in microglia and endothelial cells, with concurrent activation of the VEGF and TGF-β signaling pathways. Microglia emerged as a central hub for outgoing interactions, while endothelial cells were identified as the primary target of incoming signals within these pathways. GSEA further implicated CSRP2 in AMD progression, highlighting its role in angioimmunoblastic regulated by VEGF and TGF-β signaling pathways. In the in-vitro experiments, we found that activated microglia stimulated VEGFA, TGF-β and CSRP2, which enhanced angiogenesis, migration, proliferation, permeability, and altered the phenotype of co-cultured choroidal endothelial cells. These findings underscore the pivotal involvement of CSRP2 in mediating cellular crosstalk and signaling dynamics critical to AMD development. Microglia and endothelial cells emerged as the primary cell clusters interacting under this signaling regulation, driving angiogenesis and contributing to the pathological progression of AMD. The findings provide promise alternative therapy for AMD patients with choroidal neovascularization (CNV).

Keywords:  Age-related macular degeneration; Choroidal Neovascularization; Endothelial cells; Microglia cells; scRNA-seq

DOI:  https://doi.org/10.1016/j.exer.2025.110701
Clin Exp Ophthalmol. 2025 Oct 22.

FLVCR1 Deficiency Impairs Mitochondrial Homeostasis in Retinal Degeneration: Choline as a Potential Therapy.

Yi Wang, Hongjing Li, Yingjie Gao, Qianxiong He, Jinrui Cai, Rong Zou, Xianjun Zhu, Lin Zhang.

   BACKGROUND: The Feline Leukaemia Virus Subgroup C Receptor 1 (FLVCR1) has been recognized as a heme exporter essential for erythropoiesis, and emerging research identifies its novel function as a choline transporter. Mutations in FLVCR1 have been associated with the pathogenesis of retinitis pigmentosa (RP); however, the roles of FLVCR1 in retina remain unexplored. This study aims to elucidate the connection between FLVCR1 and RP and investigate potential therapeutic interventions.
METHODS: Utilizing CRISPR/Cas9 technology, we established retina-specific Flvcr1 knockout (SKO) and rod-specific Flvcr1 knockout (RKO) mouse models to investigate the in vivo functions of FLVCR1 in the retina. We performed optical coherence tomography (OCT) to assess the retinal thickness, electroretinography (ERG) to test the retinal function and histopathological sections and staining to analyse the pathological changes. Additionally, we administered choline supplementation treatment (CST) to evaluate its potential efficacy in alleviating symptoms of retinal degeneration.
RESULTS: Genotyping and immunoblotting analyses confirmed the successful establishment of the SKO and RKO mouse models. Retinal degeneration in SKO mice manifested at postnatal day 14, while its onset in RKO mice occurred at P25, including diminished scotopic electroretinogram (ERG) responses, progressive degeneration of photoreceptor cells, infiltration of microglia into the outer nuclear layer (ONL) and disruption of mitochondrial homeostasis. Notably, we found that choline supplementation in RKO mice alleviated the associated phenotypes.
CONCLUSIONS: We developed two innovative mouse models and revealed that FLVCR1 is critical for maintaining mitochondrial homeostasis and supporting photoreceptor survival. Choline supplementation serves as a therapeutic intervention for RP caused by FLVCR1 mutations.

Keywords:  FLVCR1; choline; mitochondrial homeostasis; retinal degeneration; retinitis pigmentosa

DOI:  https://doi.org/10.1111/ceo.70014
Brain Res Bull. 2025 Oct 21. pii: S0361-9230(25)00402-2. [Epub ahead of print] 111590

Acupuncture Improves Depression-Like Behaviors in Rats Through Gut Microbiota and TLR4/MyD88/NF-κB Pathway Modulation.

Jingyu Zeng, Meng Li, Zhuoran You, Jianguo Li, Simin Yan, Muhammad Shahzad Aslam, Junliang Shen, Peng Li, Yanyan Lin, Jingxuan Li, Hui Fang, Lianlian Ning, Yanbei Zhan, Shuqiong Huang, Tiansheng Zhang, Xianjun Meng.

   BACKGROUND: Acupuncture (AP) is used for depression, but mechanisms remain unclear. We asked whether acupuncture attenuates chronic unpredictable mild stress (CUMS)-induced depressive-like behaviors in rats and, specifically, whether its efficacy is linked to remodeling gut microbiota and inhibiting TLR4/MyD88/NF-κB signaling along the gut-brain axis with concomitant rebalancing of hypothalamic-pituitary-adrenal (HPA) activity.
METHODS: Male Sprague-Dawley rats underwent CUMS with or without acupuncture. Sucrose preference test (SPT) and forced swim test (FST) assessed behavior. Colonic injury was scored after H&E staining; microbiota were profiled by 16S rDNA sequencing. TLR4/MyD88/NF-κB expression in hypothalamus and colon was measured by Western blot/Real-time PCR; Iba1+ microglia were quantified by immunofluorescence. Serum cytokines and HPA hormones were assayed by ELISA.
RESULTS: Acupuncture increased sucrose preference (89.61 ± 2.551% vs. 73.82 ± 5.711%, P < 0.05) and reduced FST immobility (20.52 ± 3.784s vs. 46.13 ± 7.391s, P < 0.01) versus untreated CUMS. It lowered colonic injury (P < 0.05) and partly restored the Firmicutes/Bacteroidetes ratio. TLR4/MyD88/NF-κB signaling was suppressed in hypothalamus and colon (TLR4 protein -37%, P < 0.05), with fewer Iba1+ microglia (27.3 ± 3.2% vs. 45.6 ± 4.8%, P < 0.01). Serum IL-6, IL-1β, and TNF-α decreased, and HPA-axis activity normalized.
CONCLUSIONS: Acupuncture alleviates CUMS-induced depressive-like behaviors. The benefits are associated with gut microbiota remodeling, inhibition of TLR4/MyD88/NF-κB signaling, and stabilization of HPA-axis function, supporting an immune-microbiota-neuroendocrine mechanism.

Keywords:  Acupuncture; CUMS; Depression; Gut microbiota; Neuroinflammation

DOI:  https://doi.org/10.1016/j.brainresbull.2025.111590
STAR Protoc. 2025 Oct 22. pii: S2666-1667(25)00558-1. [Epub ahead of print]6(4): 104152

Protocol for generating a human iPSC-derived tri-culture model to study interactions between neurons, astrocytes, and microglia.

Alexandra M Lish, Paige C Galle, Gwendolyn A Orme, Nancy Ashour, Sarah E Heuer, Annabel J Curle, Christina R Muratore, Tracy L Young-Pearse.

  Human induced pluripotent stem cell (hiPSC) models enable disease modeling and drug screening, but standardized methods for multi-lineage co-culture remain limited. Here, we present a cryopreservation-compatible tri-culture system of neurons, astrocytes, and microglia. We describe steps for transducing induced pluripotent stem cells (iPSCs) with cell type-specific factors, generating intermediate cryopreserved stocks, differentiating each cell population, and assembling them into tri-culture. This protocol provides a reproducible platform to study dynamic interactions between human brain cells in a physiologically relevant environment. For complete details on the use and execution of this protocol, please refer to Lish et al.1,2.

Keywords:  Immunology; Neuroscience; cell Biology; cell culture; cell differentiation; stem cells

DOI:  https://doi.org/10.1016/j.xpro.2025.104152
J Vis Exp. 2025 Oct 03.

Flow Cytometry and Single-Cell Analysis for Characterizing Microglia Activation in Early Postnatal Mouse Brain Development.

Marianne Mengus, Benjamin Boucher, Roqaya Imane, Sophie Tremblay.

Microglia, the brain's resident immune cells, exhibit region and context-specific transcriptional profiles during development and disease. This protocol presents two complementary methods for studying microglial populations in mouse cerebellar tissue: flow cytometry and single-cell RNA sequencing. As the first method used, the flow cytometry-based protocol is optimized for early postnatal brains, ensuring robust cell isolation and consistency across experimental conditions. It begins with tissue dissociation using enzymatic digestion, followed by myelin removal via Percoll density gradient centrifugation to yield a high-quality neural cell suspension, and a gating strategy based on CD45 and CD11b expression. Live/dead staining ensures cell viability, and fluorochrome-conjugated antibodies are used to profile the expression of selected surface markers on microglia. Compensating controls are performed using latex beads with validated gating strategies using fluorescence minus one (FMO) control. The second method involves single-cell RNA sequencing using 10X Genomics, following the same upstream isolation steps, which enable transcriptomic profiling of microglia across conditions. Microglial clusters are identified using gene expression analysis, and differential expression analysis is conducted between experimental groups. A random forest classifier is applied solely to distinguish male and female samples when multiplexed. Together, these reproducible and adaptable protocols provide a robust framework for investigating microglial diversity in the cerebellum during early brain development and its potential alteration following experimental perturbations.

DOI: https://doi.org/10.3791/68427