Explore the vast range of titles available.

We have previously reported evidence that Nogo-A activation of Nogo-receptor 1 (NgR1) can drive axonal dystrophy during the neurological progression of experimental autoimmune encephalomyelitis (EAE). However, the B-cell activating factor (BAFF/BlyS) may also be an important ligand of NgR during neuroinflammation. In the current study we define that NgR1 and its homologs may contribute to immune cell signaling during EAE. Meningeal B-cells expressing NgR1 and NgR3 were identified within the lumbosacral spinal cords of ngr1 +/+ EAE-induced mice at clinical score 1. Furthermore, increased secretion of immunoglobulins that bound to central nervous system myelin were shown to be generated from isolated NgR1- and NgR3-expressing B-cells of ngr1 +/+ EAE-induced mice. In vitro BAFF stimulation of NgR1- and NgR3-expressing B cells, directed them into the cell cycle DNA synthesis phase. However, when we antagonized BAFF signaling by co-incubation with recombinant BAFF-R, NgR1-Fc, or NgR3 peptides, the B cells remained in the G0/G1 phase. The data suggest that B cells express NgR1 and NgR3 during EAE, being localized to infiltrates of the meninges and that their regulation is governed by BAFF signaling.

Objective: This study systematically investigated the effects and molecular mechanisms of Baishaoluoshi Decoction (BD) on synaptic plasticity in rats with post‐stroke spasticity (PSS). Methods A rat model of PSS was established using middle cerebral artery occlusion. Behavioral assessments, including modified neurological severity scores, rotarod tests, and the Modified Ashworth Scale, were employed. Synaptic ultrastructure was analyzed using transmission electron microscopy (TEM). The molecular mechanisms were explored using immunofluorescence and western blot analyses to evaluate protein expression (Nogo‐A, Nogo receptor (NgR), RhoA, Collapsin Response Mediator Protein 2 (CRMP2), and AGG) and NgR/Olig2 colocalization. BD was also tested in combination with the NgR antagonist NEP1‐40. Results BD significantly ameliorated the neurological deficits, prolonged rotarod fall latency, and reduced spasticity. TEM revealed that BD restored the synaptic ultrastructure in the peri‐infarct regions by increasing postsynaptic density (PSD) thickness and length, and narrowing synaptic clefts. BD downregulates synaptic‐plasticity‐related proteins (Nogo‐A, NgR, RhoA, AGG, and CRMP2) and attenuates oligodendrocyte‐mediated inhibitory signaling via reduced NgR/Olig2 co‐localization. BD combined with NEP1‐40 exhibits synergistic therapeutic efficacy. Conclusion BD alleviates PSS by enhancing synaptic plasticity and suppressing inhibitory signaling through multitarget modulation of neuron–glia interactions. These findings highlight BD as a promising therapeutic intervention for PSS, which is supported by molecular evidence of its effects on synaptic remodeling and functional recovery. Baishaoluoshi Decoction alleviates post‐stroke spasticity by downregulating inhibitory proteins (Nogo‐A/NgR) in the peri‐infarct brain region and reducing NgR/Olig2 co‐localization in oligodendrocytes, thereby enhancing synaptic plasticity.

Auditory experience drives neural circuit refinement during windows of heightened brain plasticity, but little is known about the genetic regulation of this developmental process. The primary auditory cortex (A1) of mice exhibits a critical period for thalamocortical connectivity between postnatal days P12 and P15, during which tone exposure alters the tonotopic topography of A1. We hypothesized that a coordinated, multicellular transcriptional program governs this window for patterning of the auditory cortex. To generate a robust multicellular map of gene expression, we performed droplet-based, single-nucleus RNA sequencing (snRNA-seq) of A1 across three developmental time points (P10, P15, and P20) spanning the tonotopic critical period. We also tone-reared mice (7 kHz pips) during the 3-d critical period and collected A1 at P15 and P20. We identified and profiled both neuronal (glutamatergic and GABAergic) and nonneuronal (oligodendrocytes, microglia, astrocytes, and endothelial) cell types. By comparing normal- and tone-reared mice, we found hundreds of genes across cell types showing altered expression as a result of sensory manipulation during the critical period. Functional voltage-sensitive dye imaging confirmed GABA circuit function determines critical period onset, while Nogo receptor signaling is required for its closure. We further uncovered previously unknown effects of developmental tone exposure on trajectories of gene expression in interneurons, as well as candidate genes that might execute tonotopic plasticity. Our single-nucleus transcriptomic resource of developing auditory cortex is thus a powerful discovery platform with which to identify mediators of tonotopic plasticity.

Nogo (RTN4) proteins and their receptors have emerged as candidate mediators of metabolic regulation and vascular pathology relevant to type 2 diabetes (T2D). The primary objective of this PRISMA-guided systematic review was to evaluate the clinical and cohort evidence for RTN4/RTN4R as potential biomarkers of T2D progression and vascular complications. A secondary objective was to synthesize preclinical mechanistic evidence on the effects of Nogo axis modulation on pathways relevant to the pathogenesis of T2D. We performed a PRISMA-guided systematic review. The protocol was not prospectively registered in PROSPERO. To ensure reproducibility, we provide complete search keywords, the screening log and the full-text exclusion table. PubMed/MEDLINE, EMBASE and Web of Science were searched for studies published 2000-2025; full search keywords are provided in the main text. The search strategy combined and free-text terms with Boolean operators. We included original preclinical and clinical studies, cohort/proteomic analyses, meta-analyses, and mechanistic papers reporting expression, function, signaling, or clinical associations of Nogo proteins/receptors in metabolic or vascular outcomes. Exclusion criteria: non-English articles, unclear methods, studies outside 2000-2025, and studies lacking primary data. Two reviewers independently screened records; conflicts were resolved by consensus. Study quality was appraised using established tools (SYRCLE for animal studies, Newcastle-Ottawa Scale for cohort/case-control studies). Preclinical evidence supports tissue-specific roles for RTN4 isoforms and receptors in the regulation of insulin secretion, proGCG → GLP-1 processing, ER homeostasis, and vascular permeability through the Src/PI3K/Akt and RhoA/ROCK axes. Cohort and proteomic analyses report associations between RTN4/RTN4R or serum NogoB and faster progression of T2D or vascular complications, but genetic assessment of causality (Mendelian randomization) has so far provided limited support in available data sets. Findings are heterogeneous with respect to directionality and tissue localization. RTN4 signaling exhibits tissue-specific mechanisms relevant to glucose regulation and vascular biology and warrants further translational study. However, heterogeneity across studies and limited genetic support for causality indicate that isoform-specific quantitative validation, longitudinal cohorts and integrated genetic-functional analyses are required before RTN4/RTN4R can be considered as clinical biomarkers.

Dopaminergic treatment in combination with rehabilitative training enhances long-term recovery after stroke. However, the underlying mechanisms on structural plasticity are unknown. Here, we show an increased dopaminergic innervation of the ischemic territory during the first week after stroke induced in Wistar rats subjected to transient occlusion of the middle cerebral artery (tMCAO) for 120 min. This response was also found in rats subjected to permanent focal ischemia induced by photothrombosis (PT) and mice subjected to PT or tMCAO. Dopaminergic branches were detected in the infarct core of mice and rats in both stroke models. In addition, the Nogo A pathway was significantly downregulated in rats treated with levodopa (LD) compared to vehicle-treated animals subjected to tMCAO. Specifically, the number of Nogo A positive oligodendrocytes as well as the levels of Nogo A and the Nogo A receptor were significantly downregulated in the peri-infarct area of LD-treated animals, while the number of Oligodendrocyte transcription factor 2 positive cells increased in this region after treatment. In addition, we observed lower protein levels of Growth Associated Protein 43 in the peri-infarct area compared to sham-operated animals without treatment effect. The results provide the first evidence of the plasticity-promoting actions of dopaminergic treatment following stroke.

Background Alzheimer’s disease is characterized by progressive accumulation of β-amyloid (Aβ)-containing amyloid plaques, and microglia play a critical role in internalization and degradation of Aβ. Our previous research confirmed that Nogo-66 binding to Nogo receptors (NgR) expressed on microglia inhibits cell adhesion and migration in vitro. Methods The adhesion and migration of microglia isolated from WT and APP/PS1 mice from different ages were measured by adhesion assays and transwells. After NEP1-40 (a competitive antagonist of Nogo/NgR pathway) was intracerebroventricularly administered via mini-osmotic pumps for 2 months in APP/PS1 transgenic mice, microglial recruitment toward Aβ deposits and CD36 expression were determined. Results In this paper, we found that aging led to a reduction of microglia adhesion and migration to fAβ 1–42 in WT and APP/PS1 mice. The adhesion and migration of microglia to fAβ 1–42 were downregulated by the Nogo, which was mediated by NgR, and the increased inhibitory effects of the Nogo could be observed in aged mice. Moreover, Rho GTPases contributed to the effects of the Nogo on adhesion and migration of microglia to fAβ 1–42 by regulating cytoskeleton arrangement. Furthermore, blocking the Nogo/NgR pathway enhanced recruitment of microglia toward Aβ deposits and expression of CD36 in APP/PS1 mice. Conclusion Taken together, Nogo/NgR pathway could take part in Aβ pathology in AD by modulating microglial adhesion and migration to Aβ and the Nogo/NgR pathway might be an important target for treating AD.

Background Nogo-A and its putative receptor NgR are considered to be among the inhibitors of axonal regeneration in the CNS. However, few studies so far have addressed the issue of local NgR complex multilateral localization within inflammation in an MS mouse model of autoimmune demyelination. Methods Chronic experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6 mice. Analyses were performed on acute (days 18–22) and chronic (day 50) time points and compared to controls. The temporal and spatial expression of the Nogo receptor complex (NgR and coreceptors) was studied at the spinal cord using epifluorescent and confocal microscopy or real-time PCR. Data are expressed as cells/mm 2 , as mean % ± SEM, or as arbitrary units of integrated density. Results Animals developed a moderate to severe EAE without mortality, followed by a progressive, chronic clinical course. NgR complex spatial expression varied during the main time points of EAE. NgR with coreceptors LINGO-1 and TROY was increased in the spinal cord in the acute phase whereas LINGO-1 and p75 signal seemed to be dominant in the chronic phase, respectively. NgR was detected on gray matter NeuN + neurons of the spinal cord, within the white matter inflammatory foci (14.2 ± 4.3 % NgR + inflammatory cells), and found to be colocalized with GAP-43 + axonal growth cones while no β-TubIII + , SMI-32 + , or APP + axons were found as NgR + . Among the NgR + inflammatory cells, 75.6 ± 9.0 % were microglial/macrophages (lectin + ), 49.6 ± 14.2 % expressed CD68 (phagocytic ED1 + cells), and no cells were Mac-3 + . Of these macrophages/monocytes, only Arginase-1 + /NgR + but not iNOS + /NgR + were present in lesions both in acute and chronic phases. Conclusions Our data describe in detail the expression of the Nogo receptor complex within the autoimmune inflammatory foci and suggest a possible immune action for NgR apart from the established inhibitory one on axonal growth. Its expression by inflammatory macrophages/monocytes could signify a possible role of these cells on axonal guidance and clearance of the lesioned area during inflammatory demyelination.

NogoA inhibits neurite outgrowth of motoneurons (NOM) through interaction with its receptors, Nogo66/NgR. Inhibition of Nogo receptors rescues NOM, but not to the extent exhibited by NogoA-knockout mice, suggesting the presence of other pathways. We found that NogoA-overexpressing muscle cells reduced phosphoglycerate kinase 1 (Pgk1) secretion, resulting in inhibiting NOM. Apart from its glycolytic role and independent of the Nogo66 pathway, extracellular Pgk1 stimulated NOM by triggering a reduction of p-Cofilin-S3, a growth cone collapse marker, through decreasing a novel Rac1-GTP/p-Pak1-T423/p-P38-T180/p-MK2-T334/p-Limk1-S323/p-Cofilin-S3 molecular pathway. Not only did supplementary Pgk1 enhance NOM in defective cells, but injection of Pgk1 rescued denervation in muscle-specific NogoA-overexpression of zebrafish and an Amyotrophic Lateral Sclerosis mouse model, SOD1 G93A. Thus, Pgk1 secreted from muscle is detrimental to motoneuron neurite outgrowth and maintenance.

Nogo-66 receptor 1 (NgR1) binds a variety of structurally dissimilar ligands in the adult central nervous system to inhibit axon extension. Disruption of ligand binding to NgR1 and subsequent signaling can improve neuron outgrowth, making NgR1 an important therapeutic target for diverse neurological conditions such as spinal crush injuries and Alzheimer’s disease. Human NgR1 serves as a receptor for mammalian orthoreovirus (reovirus), but the mechanism of virus–receptor engagement is unknown. To elucidate how NgR1 mediates cell binding and entry of reovirus, we defined the affinity of interaction between virus and receptor, determined the structure of the virus–receptor complex, and identified residues in the receptor required for virus binding and infection. These studies revealed that central NgR1 surfaces form a bridge between two copies of viral capsid protein σ3, establishing that σ3 serves as a receptor ligand for reovirus. This unusual binding interface produces high-avidity interactions between virus and receptor to prime early entry steps. These studies refine models of reovirus cell-attachment and highlight the evolution of viruses to engage multiple receptors using distinct capsid components.

Nogo proteins, also known as Reticulon-4, have been identified as myelin-derived inhibitors of neurite outgrowth in the central nervous system (CNS). There are three Nogo variants, Nogo-A, Nogo-B and Nogo-C. Recent studies have shown that Nogo-A/B is abundant in macrophages and may have a wider effect on inflammation. In this review, we focus mainly on the possible roles of Nogo-A/B on polarization and recruitment of macrophages and their involvement in a variety of inflammatory diseases. We then discuss the Nogo receptor1 (NgR1), a common receptor for Nogo proteins that is also abundant in microglia/macrophage in the CNS. Interaction of Nogo and NgR1 in microglia/macrophage may affect the adhesion and polarization of macrophages that are involved in multiple neurodegenerative diseases, including Alzheimer’s disease and multiple sclerosis. Overall, this review provides insights into the roles of Nogo proteins in regulating macrophage functions and suggests that, potentially, Nogo proteins maybe a new target in the treatment of inflammatory diseases.