Modulatory effects of genetic vs. pharmacological HCN4 channel inhibition on stimuli transmission during acute pain.

We develop Spatial Perturb-Seq, an in vivo CRISPR technology that interrogates multiple genes within single cells of intact tissues, compatible with both sequencing-based and probe-based spatial technologies. We apply Spatial Perturb-Seq to knock out risk genes for neurodegenerative diseases in the mouse brain, uncovering cell autonomous and cell-cell microenvironmental effects within the spatially intact tissue. Spatial Perturb-Seq functionally screens multiple genes in situ and in vivo, bypasses cell processing steps that skew cell type representation, identifies intracellular and intercellular effects of knockouts, and identifies candidate genes underlying dysregulated neuronal intercellular communication pathways.

Brain-wide mapping of oligodendrocyte organization, oligodendrogenesis, and myelin injury.

Introduction: Sustained microglial activation has been recognized as a central component of chronic neuroinflammation, integrating cytokine amplification, metabolic reprogramming, and circuit remodeling in the development of persistent neurological conditions. Objective: To systematically analyze the neuroimmune mechanisms involved in neurological chronification, emphasizing the role of microglia as an integrative axis between inflammatory signaling, synaptic plasticity, and systemic dysfunction. Methodology: This is a systematic review conducted according to PRISMA 2020 guidelines, with searches performed in PubMed, Scopus, BVS, and SciELO databases, including full-text open-access articles published within the last five years. After eligibility screening and qualitative synthesis, studies addressing persistent microglial activation and pro-inflammatory cytokine amplification were analyzed. Results: Findings demonstrate that microglia orchestrate intracellular molecular pathways, bioenergetic collapse, bidirectional glia–neuron communication, and peripheral influences, establishing a self-regenerative neuroinflammatory state responsible for maintaining central hyperexcitability and circuit dysfunction. Cytokine amplification was identified as a structural element of chronification, sustaining synaptic reorganization and resistance to spontaneous resolution. Conclusion: It is concluded that neurological chronification results from profound functional reprogramming of microglia across molecular, cellular, circuital, and systemic dimensions, limiting the effectiveness of late isolated interventions and reinforcing the need for early multimodal therapeutic strategies targeting inflammation, glial metabolism, and synaptic plasticity.

This study tested the hypothesis that during localized facial cooling the human trigeminal reflex regulates sympathetic neuronal communication strategies. In fifteen healthy individuals we measured action potential (AP) discharge in muscle sympathetic nerve activity (MSNA; peroneal microneurography and continuous wavelet transform) during baseline (BSL) and three minutes of trigeminal nerve stimulation (TGS; cold pack on face). Face temperature and discomfort were measured. TGS increased total integrated MSNA via differential regulation of sympathetic AP discharge versus AP recruitment. TGS increased sympathetic AP discharge frequency (BSL: 216 ± 150, TGS-1: 511 ± 335, TGS-2: 476 ± 323, TGS-3: 340 ± 160 APs/min, all P < 0.01). By contrast, TGS recruited previously silent larger sympathetic APs during TGS-1 and TGS-2, but not TGS-3 (BSL: 13 ± 3, TGS-1: 18 ± 4, TGS-2: 17 ± 4 clusters, both P < 0.01, TGS-3: 15 ± 4 clusters, P = 0.17). Compared to BSL, the sympathetic AP latency-size relationship was reset downwards to faster latencies during TGS-1 (Δ-63 ± 6 ms, P < 0.01) and TGS-2 (Δ-31 ± 13 ms, P = 0.02) but not TGS-3 (Δ-8 ± 1 ms, P = 0.32). Across BSL and TGS sympathetic AP recruitment (r = 0.58; P < 0.01) and latency (r = -0.52; P < 0.01) were related to perceptual discomfort but not face temperature. Thus, during localized facial cooling, trigeminal reflex activation and perceptual discomfort increase the discharge of previously active sympathetic neurons, recruit previously silent larger neurons, and reduce neuronal discharge latency.

The multi-factorial pathophysiology of acquired epilepsies lends itself to a multi-targeting therapeutic approach. MicroRNAs (miRNA) are short noncoding RNAs that individually can negatively regulate dozens of protein-coding transcripts. Previously, we reported that central injection of antisense oligonucleotides targeting microRNA-134 (Ant-134) shortly after status epilepticus potently suppressed the development of recurrent spontaneous seizures in rodent models of temporal lobe epilepsy. The mechanism(s) of these anti-seizure effects remain, however, incompletely understood. Here we show that intracerebroventricular microinjection of Ant-134 in male mice with pre-existing epilepsy caused by intraamygdala kainic acid-induced status epilepticus potently reduces the occurrence of spontaneous seizures. Recordings from ex vivo brain slices collected 2-4 days after Ant-134 injection in epileptic mice, detected a number of electrophysiological phenotypic changes consistent with reduced excitability. Specifically, Ant-134 reduced action potential bursts after current injection in CA1 neurons and reduced excitatory post-synaptic current frequencies in CA1 neurons. Ant-134 also reduced general network excitability, including attenuating pro-excitatory CA1 responses to Schaffer collateral stimulation in hippocampal slices from epileptic mice. Together, the present study demonstrates inhibiting miR-134 reduces single neuron and network hyperexcitability in mice and extends support for this approach to treat drug-resistant epilepsies.Significance statement Temporal lobe epilepsy is one of the most common forms of drug-resistant epilepsy. Identifying molecular regulators of enduring states of hyperexcitability may lead to new therapeutic approaches. MicroRNAs are short noncoding RNAs that act post-transcriptionally to lower levels of sets of protein-coding genes. Here we show that inhibiting miR-134 reduces spontaneous seizures in mice with active epilepsy. Electrophysiologic recordings from brain slices collected when mice were transitioning to fewer seizures revealed changes to both single neuron and inter-regional communication properties that may explain the reduction in hippocampal network excitability. The findings support the development of this microRNA-targeting approach for epilepsy.

Synaptic aging is a core manifestation of brain aging arising from the convergence of fundamental biological aging processes, including genomic instability, loss of proteostasis, mitochondrial dysfunction, oxidative stress, and chronic low-grade inflammation. As highly energy-dependent and protein-rich sites of neuronal communication, synapses are particularly vulnerable to age-associated molecular stress. Accumulating evidence indicates that age-related impairments in synaptic vesicle trafficking, recycling, and neurotransmitter homeostasis precede neuronal loss and represent early drivers of cognitive decline and neurodegeneration. Disruption of vesicle dynamics compromises neurotransmitter release, synaptic plasticity, and circuit stability, thereby accelerating synaptic failure. Dysregulation of key neurotransmitter systems, including acetylcholine, dopamine, glutamate, and γ-aminobutyric acid, further exacerbates synaptic dysfunction and cognitive impairment. These changes are driven by interconnected aging mechanisms, wherein impaired proteostasis promotes the accumulation of dysfunctional synaptic proteins, mitochondrial dysfunction limits ATP availability for vesicle mobilisation, and persistent neuroinflammation heightens synaptic vulnerability. Emerging evidence also implicates age-related blood-brain barrier disruption and gut-brain axis dysregulation as additional modulators of synaptic integrity via immune, metabolic, and neurochemical pathways. This review synthesises recent advances in understanding the molecular mechanisms of synaptic aging, with a focus on vesicle dynamics and neurotransmitter imbalance, and discusses therapeutic strategies aimed at enhancing synaptic resilience to promote healthy brain aging.

CNTNAP1 encodes the Contactin-Associated Protein 1 (CNTNAP1), also known as Caspr1, which is a transmembrane protein critical for nervous system function. CNTNAP1 is localized to the paranodal regions of all myelinated axons, flanking either side of the node of Ranvier. It plays a vital role in axonal domain organization and is essential for the propagation of action potentials along nerve fibers. This specialized arrangement of axonal domains, which contain distinct molecular complexes, enables saltatory conduction and significantly increases the speed and efficiency of neuronal communication. To date, there are 47 children with biallelic CNTNAP1 variants who have been reported exhibiting a wide spectrum of phenotypes including congenital hypomyelinating neuropathy, hypotonia, and joint contractures among other clinical features. In this review, we compiled all previously published cases and detailed the specific genetic variants of every known individual, including clinical manifestations. Additionally, we present seven new cases of individuals identified through direct collaborations with clinicians and families, bringing the total to 54 individuals who harbor biallelic variants in CNTNAP1. This review and the additional case studies demonstrate that while children with CNTNAP1 mutations can present with a broad spectrum of symptoms, there is a recurrence of key clinical features across these cases. These key features commonly include respiratory distress, generalized hypotonia, hypomyelination, intellectual disabilities, and reduced life expectancy. These newly described cases provide valuable insights into the phenotypic diversity of CNTNAP1 variants, deepening our understanding of the clinical impact in patients with this rare genetic disorder.

Neuronal communication relies on neurotransmitter release from synaptic vesicles. The endocytic protein AP180 is critical for efficient vesicle recycling at presynaptic terminals, and its loss impairs neurotransmission, producing reduced release frequency, enlarged synaptic vesicles, and increased quantal amplitude. Yet how AP180 controls vesicle size and whether vesicle size influences release remains unclear. Here, we show that the C-terminal Assembly domain (AD) of AP180 determines vesicle size and thereby regulates release properties in Caenorhabditis elegans. An AP180 variant lacking the AD (AP180∆AD) increases release frequency, contrasting sharply with the reduced transmission in ap180 null mutants, yet fails to correct the vesicle size or quantal amplitude. These enlarged vesicles evade curvature-dependent inhibition by complexin, a presynaptic regulator of fusion, while remaining dependent on complexin for evoked responses. This selective escape reveals that vesicle size influences release dynamics through curvature-sensing proteins. Replacing the AP180 AD with actin-binding motifs restores normal vesicle size, quantal amplitude, and release frequency, indicating that actin interactions are both necessary and sufficient for AD function. Biochemically, we show that the intrinsically disordered AD forms condensates that enrich actin monomers and nucleate filament assembly, while full-length AP180 couples PIP2-rich membranes to actin filaments. Together, these findings reveal that the AP180 AD regulates synaptic vesicle size through actin binding, establishing vesicle morphology as a key influencer of curvature-dependent release control.

Neuronal communication relies on neurotransmitter release from synaptic vesicles. The endocytic protein AP180 is critical for efficient vesicle recycling at presynaptic terminals, and its loss impairs neurotransmission, producing reduced release frequency, enlarged synaptic vesicles, and increased quantal amplitude. Yet how AP180 controls vesicle size and whether vesicle size influences release remains unclear. Here, we show that the C-terminal Assembly domain (AD) of AP180 determines vesicle size and thereby regulates release properties in Caenorhabditis elegans. An AP180 variant lacking the AD (AP180∆AD) increases release frequency, contrasting sharply with the reduced transmission in ap180 null mutants, yet fails to correct the vesicle size or quantal amplitude. These enlarged vesicles evade curvature-dependent inhibition by complexin, a presynaptic regulator of fusion, while remaining dependent on complexin for evoked responses. This selective escape reveals that vesicle size influences release dynamics through curvature-sensing proteins. Replacing the AP180 AD with actin-binding motifs restores normal vesicle size, quantal amplitude, and release frequency, indicating that actin interactions are both necessary and sufficient for AD function. Biochemically, we show that the intrinsically disordered AD forms condensates that enrich actin monomers and nucleate filament assembly, while full-length AP180 couples PIP2-rich membranes to actin filaments. Together, these findings reveal that the AP180 AD regulates synaptic vesicle size through actin binding, establishing vesicle morphology as a key influencer of curvature-dependent release control.

Alzheimer's disease (AD) is characterized by progressive cognitive decline, with amyloid beta oligomers (AβOs) emerging as the most neurotoxic species and acting as early triggers of cellular alterations. Before the appearance of other protein aggregates, AβOs disrupt the dynamics and stability of the neuronal cytoskeleton, a structure essential for maintaining neuronal morphology, axonal transport, and synaptic plasticity. Experimental evidence demonstrates that AβOs promote microtubule disassembly, Tau hyperphosphorylation, reduced kinesin levels, impaired axonal transport, and alterations in actin dynamics through the LIMK-cofilin signaling pathway. In addition, increased levels of neurofilament light chain have been identified as an early biomarker of axonal damage. Notably, these cytoskeletal disturbances arise in the absence of extensive neuronal death, underscoring the cytoskeleton as a critical early target in AD pathogenesis. In this review, we analyze cytoskeletal alterations induced by AβOs in neurons and discuss how these changes may contribute to disrupted neuronal communication, a defining early hallmark of AD pathology.

Study on the effects of gestational arsenic exposure on the developmental toxicity of brain tissue in mice offspring using network toxicology and RNA-seq.

Extracellular vesicle dysfunction contributes to synaptic and cognitive deficits in a mouse model of Angelman syndrome.

A voltage-dependent switch underlies efficient yet specific learning and memory.

Down syndrome (DS; trisomy 21) confers a ~100-fold increased risk of Hirschsprung disease (HSCR), yet the causal contributions of specific chromosome 21 genes remain unresolved. Here we show that increased dosage of SOD1 alone is sufficient to perturb enteric nervous system (ENS) development. We engineered a humanized SOD1 trisomic mouse line by inserting a 28 kb human SOD1 locus into ROSA26 and genetically profiled the distal colon at postnatal day 0 using single-cell RNA-seq and immunofluorescence. Sod1/SOD1 was elevated ~1.5X in the ENS but varied by cell type, with transcriptionally active progenitors showing the greatest increase. Cell composition shifted toward transcriptionally active cells and glia, with concomitant loss of excitatory and inhibitory motor neurons and interneurons. Genetically, Sod1/SOD1 trisomy downregulated synaptic and neuronal communication programs but upregulated DNA replication/cell-cycle and genome maintenance pathways, especially within glia. Consequently, key HSCR genes were dysregulated: Ret, Ednrb, and Sema3c were decreased, while Sema3a ,a negative guidance cue, was increased. Ret was selectively reduced in inhibitory and excitatory motor neurons and progenitors, unchanged in glia, and reduced at the protein level in vivo. Within glia, Sod1/SOD1 was particularly elevated in proliferating/active glia with a glia-specific bias toward endogenous mouse Sod1 expression. Taken together, these data support a dual mechanism whereby increased Sod1/SOD1 dosage suppresses RET-dependent neurogenesis while independently promoting reactive/proliferative glial states. Thus, SOD1 is sufficient to alter ENS development significantly and provide the susceptibility substrate for HSCR with further reductions in RET gene expression leading to aganglionosis.

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an immune-mediated neurological disorder driven by dysregulated neuroimmune interactions, yet the molecular architecture linking tumor-associated immune activation, peripheral immunity, and neuronal dysfunction remains insufficiently understood. In this study, we established an integrative computational framework that combines multi-tissue transcriptomic profiling, weighted gene co-expression network analysis, immune deconvolution, and machine learning-based feature prioritization to systematically characterize the regulatory landscape of the disease. Joint analysis of three independent GEO datasets spanning ovarian teratoma tissue and peripheral blood transcriptomes identified 2001 consistently dysregulated mRNAs, defining a shared tumor-immune-neural transcriptional axis. Across multiple feature selection algorithms, ACVR2B and MX1 were reproducibly prioritized as immune-associated candidate genes and were consistently downregulated in anti-NMDAR encephalitis samples, showing negative correlations with neutrophil infiltration. Reconstruction of an integrated mRNA-miRNA-lncRNA regulatory network further highlighted a putative core axis (ENSG00000262580-hsa-miR-22-3p-ACVR2B), proposed as a hypothesis-generating regulatory module linking non-coding RNA regulation to immune-neuronal signaling. Pathway and immune profiling analyses demonstrated convergence of canonical immune signaling pathways, including JAK-STAT and PI3K-Akt, with neuronal communication modules, accompanied by enhanced innate immune signatures. Although limited by reliance on public datasets and small sample size, these findings delineate a systems-level neuroimmune regulatory program in anti-NMDAR encephalitis and provide a scalable, network-based multi-omics framework for investigating immune-mediated neurological and autoimmune disorders and for guiding future experimental validation.

The metabolite acetyl-CoA plays a central role in cellular metabolic homeostasis. As part of the secretory pathway, acetyl-CoA is imported into the endoplasmic reticulum (ER) by a membrane-bound transporter AT-1 (SLC33A1). AT-1 has been linked to peripheral neuropathy (heterozygous mutations), developmental delay with premature death (homozygous mutations) and intellectual disability with progeria (duplication). These phenotypes can be reproduced in the mouse. Here, we show that AT-1 overexpression in primary neurons impacts diverse phenotypes related to neuronal function and plasticity. At the gene level, AT-1 induces brain aging signatures, and key differences in ribosomal and synaptic processes were identified in both the transcriptome and the proteome. Changes in mitochondria-associated pathways were reflected in an increase in expression of mitochondrial master regulator PGC-1α and its target genes. Functionally, marked differences in mitochondrial membrane potential, architecture, and respiration were detected. Tracing experiments indicated altered glucose utilization in glycogen storage and nucleotide production. Shifts in redox metabolism were linked to differences in levels of NAD-dependent SIRT1 and CtBP2, with consequences for acetylated lysine modification. Depletion of lipid stores was associated with greater plasticity in fuel substrate utilization and a major shift in cellular lipid composition. These broad-scale changes in metabolism were coincident with reduced expression of synaptic proteins and reduced activity among synaptic networks, indicating that neuronal electrophysiology and network communication are coordinated at least in part through neuronal acetyl-CoA metabolism.

The brain employs a sophisticated and multi-layered system to maintain its delicate acid-base balance, ensuring optimal conditions for neuronal and glial function. This intricate regulation involves a combination of chemical buffering, active transport mechanisms, and systemic controls. The balance of pH in mammalian cells is vital for the control of metabolism, as hydrogen and hydroxyl ions are essential. It is important for the nervous system to keep its pH in a neutral range (7.2-7.6) for proper function. Even small pH changes can impact neuron activity, synaptic transmission, and communication between cells. Many membrane proteins sensitive to pH changes play vital roles in neurotransmission. Recent research has identified pH-sensitive proteins that respond to acidic (pH 5) and alkaline (pH 9) conditions, influencing various cellular activities. This review discusses these pH-sensitive proteins in neurons.

Neuroinflammation is a hallmark of many neurological disorders such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS). Growing evidence indicates that extracellular vesicles (EVs) are key regulators of neuroimmune communication. EVs derived from neurons, microglia, astrocytes, and peripheral immune cells transfer bioactive molecules, including proteins, lipids, and non-coding RNAs (ncRNAs), that modulate synaptic activity, inflammatory signaling, and the spread of pathogenic factors. By directly interacting with CNS cells, EVs exert both pro-inflammatory and anti-inflammatory effects in shaping the neuroinflammatory landscape. This review summarizes advances in EV-mediated neuroimmune crosstalk; highlights microglia–neuron communication and the regulatory roles of ncRNAs carried by EVs; and discusses the therapeutic potential of EV-based approaches and immune-modulating compounds, such as natural polyphenols, in mitigating neuroinflammation. Together, these insights underscore EVs as critical regulators of the CNS immune landscape and promising targets for novel therapeutic strategies.

INTRODUCTIONAlzheimer's disease (AD) is a progressive neurodegenerative disorder with limited treatments and poorly defined environmental risks. Micro‐ and nanoplastics (MNPs) are widespread pollutants linked to neurotoxicity, but their role in AD remains unclear.METHODSWe investigated the effects of 90‐day intragastric exposure to polystyrene nanoplastics (PS‐NPs) in amyloid precursor protein/presenilin 1 (APP/PS1) mice using behavioral tests, brain imaging, histopathology, and cell‐type‐resolved proteomics.RESULTSPS‐NPs exacerbated cognitive deficits and hippocampal damage in APP/PS1 mice. Proteomic and CellChat analyses revealed PS‐NPs enhanced neuroglial communication through the collagen–integrin axis. In vitro triculture demonstrated that PS‐NPs strengthened collagen‐mediated astrocyte–microglia–neuron signaling, whereas in vivo blockade with TC‐I 15 suppressed collagen activation and improved cognition in PS‐NP‐exposed APP/PS1 mice. Single‐nucleus RNA sequencing of human AD brains validated conserved activation of collagen signaling.DISCUSSIONOur findings highlight that PS‐NPs exacerbate cognitive impairment in AD by driving collagen‐dependent neuroglial dysfunction, establishing MNPs as modifiable environmental risk factors.HighlightsMNPs act as environmental risk factors that worsen cognitive impairment in AD.PS‐NPs trigger glial–neuronal communication via the collagen–integrin axis in AD.PS‐NP‐induced astrocyte‐ and microglia‐derived collagen, driving neurotoxicity in AD.TC‐I 15 blocked collagen signaling and rescued cognition in PS‐NP‐exposed AD mice.Collagen signaling was upregulated in human AD brains, confirming disease relevance.