Neural Cell Adhesion Molecule Research Articles

Background: The goal of tissue regeneration is to restore structure and function. In adult regenerative wound healing, dermal fibroblasts exhibit multipotency and can be reprogrammed into lineages such as hair follicle cells and adipocytes, etc. Neural cell adhesion molecule 1 (NCAM1), a membrane-bound adhesion protein expressed in dermal fibroblasts, plays a key role in cell-cell and cell-matrix interactions and has been implicated in fate transitions during tissue remodeling. NCAM1 is absent in normal endothelium but is aberrantly expressed in tumor-derived endothelial cells, where it promotes capillary morphogenesis. These observations suggest that NCAM1+ fibroblasts may represent a progenitor-like state more capable of endothelial conversion than NCAM1- cells. While angiogenesis is the main vascularization process in adult wounds, vasculogenesis from progenitors like fibroblasts may also contribute. Fibroblast-to-endothelial reprogramming has been demonstrated in vitro using defined reprogramming factors, but its in vivo evidence remains to be investigated. We hypothesized that NCAM1+ dermal fibroblasts give rise to a subset of regenerated endothelial cells. Aims: (1) Characterize vasculature formation during regenerative wound healing (2) Identify progenitor populations and reprogramming cues, including transcription factors and adhesion molecules Method: Using a wound-induced hair neogenesis (WIHN) mouse model, we performed scRNA sequencing and RNA velocity analyses on post-wounding day 14. Wholemount immunostaining assessed vascular morphology and cell identity. NCAM1-CreERT2×ROSA26 reporter mice for lineage tracing. Results: The regenerated wound bed showed two contrasting vasculature patterns: disrupted, discontinuous vessels in the regenerating wound center and organized vasculature in the wound margin. scRNA-seq and velocity analyses indicated PECAM1+ cells may originate from NCAM1+ fibroblast-like cells that also expressed fibroblast-to-endothelial cells reprogramming factors such as FOXO1, TAL1 and SOX17. Wholemount staining revealed individual cells and a fraction of endothelial cells co-expressing PECAM1, PDGFRα, and NCAM1 in the capillary-like vasculature in wound dermis. Conclusion: Our findings support vasculogenesis during regenerative wound healing, with NCAM1+ fibroblasts contributing to endothelial cell populations. These results provide new insights into fibroblast-endothelial plasticity and vascular regeneration in adult tissue regeneration.

Clinical trials have shown favorable effects of exercise on frailty, supporting physical activity (PA) as a treatment and prevention strategy. Proteomics studies suggest that PA alters levels of many proteins, some of which may function as molecules in the biological processes underlying frailty. However, these studies have focused on structured exercise programs or cross-sectional PA-protein associations. Therefore, the effects of long-term PA on frailty-associated proteins remain unknown. Among 14,898 middle-aged adults, we emulated a target trial that assigned individuals to either (i) achieve and maintain the recommended PA level (≥ 150min/week of moderate-to-vigorous physical activity [MVPA]) through 6 (± 0.3) years of follow-up or (ii) follow a "natural course" strategy, where all individuals engage in various amounts of habitual MVPA. We estimated the effects of long-term adherence to recommended MVPA versus the natural course strategy on 45 previously identified frailty-associated proteins at the end of the follow-up using inverse probability of weighting (IPW) and iterative conditional expectations (ICE). We found that long-term adherence to recommended MVPA improved the population levels of many frailty-associated proteins (ranged from 0.04 to 0.11 standard deviation); the greatest benefits were seen in proteins involved in the nervous system (e.g., voltage-dependent calcium channel subunit alpha-2/delta-3 [CACNA2D3], contactin-1 [CNTN1], neural cell adhesion molecule 1 [NCAM1], and transmembrane protein 132D [TMEM132D]) and inflammation (e.g., high-temperature requirement serine protease A1 [HTRA1] and C-reactive protein [CRP]). Our findings suggest improved nervous system and reduced inflammation as the biological basis of long-term engagement in adequate PA as an intervention strategy for frailty.

A new approach for treating AD: Guifu Dihuang Pills improves brain insulin resistance by promoting NrCAM to activate the EGFR/PI3K/Akt signaling pathway.

Resistance to 5-fluorouracil (5-FU) remains an obstacle to effective colorectal cancer (CRC) treatment. Genetic alterations play significant roles in the development of drug-induced chemoresistance, leading to tumor recurrence and increased aggressiveness. This study sought to characterize the transcriptomic profiles of 5-FU-resistant CRC cells. HCT116 colon cancer cells were progressively exposed to increasing concentrations of 5-FU to induce resistance. Chemoresistance and aggressiveness were investigated using MTT, clonogenic, and scratch assays. Transcriptomic alterations were analyzed with next-generation sequencing (NGS). Our results revealed that 5-FU-resistant cells exhibited cross-resistance and enhanced invasive potential compared to parental HCT116 cells (HCT116-PT cells), characteristics that were associated with upregulation of matrix metalloproteinases (MMP-2 and MMP-9). Notably, we also observed significant overexpression of T cell immunoreceptor with Ig and ITIM domains (TIGIT) and cell adhesion-related genes, including neurexophilin and PC-esterase domain family member 1 (NXPE1) and neural cell adhesion molecule 1 (NCAM1). Non-coding RNAs such as microRNA-6789 (miR-6789), miR-5006, and miR-7107 were also upregulated. Pathway analysis suggested that enhanced cell survival, invasion, and apoptosis resistance in 5-FU-resistant cells may be due to the activation of several genes in the PI3K-AKT signaling pathway. In conclusion, our findings describe the transcriptomic features of chemoresistant CRC cells that are associated with aggressive tumor behavior. These insights may support the development of targeted therapies to overcome 5-FU resistance in CRC.

BackgroundFOLFOX, a commonly prescribed chemotherapeutic regimen, associated with significant neurotoxicity, that necessitates stop administration in some cases, hence, this study aimed to investigate the molecular mechanisms underlying FOLFOX-induced neurotoxicity in the brain and sciatic nerve, and determining its cerebral concentration via HPLC technique.Methods48 rats were divided into four groups: normal control, Oxaliplatin (6 mg/kg), 5-Fluorouracil (50 mg/kg), and a combination group (oxaliplatin 6 mg/kg + 5-fluorouracil 50 mg/kg). Behavioral tests in addition to samples collection from cerebral tissues, sciatic nerves, and blood were conducted. Tissue histological and biochemical changes were determined, including oxidative stress markers (Nrf2, SOD2, HO-1), apoptotic proteins (Bax, cCaspase-3, Bcl-2), and inflammatory biomarkers (COX-II, TNF-α, IL-6, NF-κβ). A new HPLC method was developed and validated to quantify oxaliplatin and 5-fluorouracil (5-Flu) concentrations in the brain tissue.ResultsBoth oxaliplatin and 5-Flu induced a substantial oxidative stress, evidenced by reduced expression of Nrf2, SOD2, and HO-1 proteins, associated with a significant upregulation of the pro-apoptotic proteins Bax and cleaved caspase-3, and downregulation of the anti-apoptotic protein Bcl-2. Inflammatory markers were increased in all treated groups, and the highest levels were observed in the combination group. HPLC analysis confirmed a significantly higher concentration of both drugs in the cerebral tissue of the combination group. Histopathological findings revealed neuronal damage and inflammation associated by increased Glial fibrillary acidic protein (GFAP) and decreased neural cell adhesion molecule (NCAM) expression. Behavioral assessments demonstrated markedly reduced pain thresholds in treated animals.ConclusionThis study identified a novel mechanisms underlying FOLFOX neurotoxicity involving activation of the pro-apoptotic BAX/cCaspase-3 pathway and suppression of the Nrf2/KEAP-1/SOD2/HO-1 antioxidant defense mechanism. These disorders induced a neuronal injury, evidenced by altered GFAP and NCAM expression. The findings highlight the synergistic role of FOLFOX components in driving oxidative stress, apoptosis, and inflammation, collectively contributing to neurotoxicity.

Brain-Derived Extracellular Vesicles (BDEVs) have been associated with important roles in functional neuron networks. However, the various models that have been used to study these roles fail to account for all the specificities of the human brain. This study presents a microfluidic platform capable of injecting and/or collecting BDEVs from Organotypic culture of Post-mortem Adult human Brain explants (OPAB) cultured at the air-liquid interface, while measuring electrical activity in real-time on 3D-microelectrode arrays (MEA). The platform design and custom-made program to control the system allows the automatic collection of BDEVs over days. Mass spectrometry analyses highlight that BDEVs are significantly enriched with synaptic proteins, such as Neural cell adhesion molecule, Syntaxin-1A, and Synaptopodin, known to regulate synaptic plasticity. Using the MEA-embedded air-liquid microfluidic platform, it is shown that BDEVs injection on OPAB induces a significant decrease of local field potential compared to mock conditions, in particular for high frequency oscillations. Finally, a machine learning framework, experimentally validated, revealed that the co-treatment of OPAB with BDEVs and GW4869, an inhibitor of exosome production, can counteract electrical perturbations induced by BDEVs alone. Together, this work provides innovative methodological developments, that contributed to reveal the diverse biological functions of BDEVs on neural activity.

Background: Close Homolog of L1 (CHL1), a neural cell adhesion molecule, plays a critical role in cortical development, but its isoform-specific and stage-dependent functions remain poorly defined. This study examines the differential effects of CHL1 presented either apically (CHL(S)) or basally (CHL(B)) on cortical neuron differentiation and maturation at key developmental stages. Methods: Using human embryonic stem cell-derived cortical neurons, we performed quantitative gene expression analyses and morphometric assessments at Days 28, 35 and 42 to evaluate how CHL1 presentation affects neuronal differentiation. Result: At early differentiation (Day 28), CHL1 showed minimal effects on gene expression. By Day 35, CHL(S) suppressed deep-layer markers (Tbr1, Ctip2) and Tbr2, suggesting inhibition of intermediate progenitor expansion. In contrast, CHL(B) maintained or elevated Ctip2, Satb2 and Brn2, indicating support for laminar identity stabilization. By Day 42, orientation-specific effects persisted with CHL(S) suppressing Cux1 and CHL(B) promoting Ctip2. Notably, CHL1 did not affect neurite morphology at any stage examined. These findings position CHL1 as a transcriptional regulator of cortical neuron identity, with orientation- and stage-specific effects on gene expression but not morphogenesis. The results highlight its role in cortical layering and support further investigation into CHL1-mediated signaling pathways in neuro developmental disorders.

ABSTRACTIn neurodegenerative diseases, brain‐derived extracellular vesicles (EVs)/exosomes from blood offer a great opportunity to explore their contents for their utility as biomarkers. However, the conventional methodologies for the purification of EVs from complex biofluids have many limitations, restricting their clinical implementation. We aimed to optimize a direct, less time‐consuming, affordable, and reliable nanowire‐based method to isolate neuronal EVs from blood plasma. Here, we improved a simple and direct methodology using multiple antibody‐coated magnetic nanowires for efficient and rapid isolation of neuronal EVs (ExoAssay) from human plasma. We characterized the isolated EVs and validated the protocol using multiple approaches, for example, nanoparticle tracking analysis (NTA), immunoblotting, and transmission electron microscopy (TEM). We purified round‐shaped EVs with an average size of 116 nm. We identified the general markers of EVs including CD9, CD63, CD81, and Flotillin‐1 and two neuronal EV markers L1‐cell adhesion molecule (L1CAM) and neural cell adhesion molecule (NCAM) via immunoblotting. Interestingly, the levels of T‐Tau and P‐Tau were upregulated in EVs isolated from Alzheimer's patients (n = 30), in comparison with healthy controls. Furthermore, there were no significant differences between CSF‐ and EV‐based Tau levels. The high‐throughput mass‐spectrometry analysis of isolated EVs revealed 280 proteins as significantly modified in Alzheimer's disease cases in comparison with controls. The presented nanotechnology‐based methodology offers an innovative and efficient tool for EV‐based biomarker investigations and clinical utility by simplifying the enrichment of CNS‐originated exosomes from complex biological fluids. This methodology opens up the avenue for longitudinal monitoring of important disease‐related proteins in the brain by analysis of brain‐derived EVs from blood plasma using simple blood withdrawal.

Proteomic study of plasma and L1CAM-captured exosomal proteins in children with autism spectrum disorders.

MECHANISTIC OVERVIEW OF PROTEIN-SPECIFIC POLYSIALYLATION.

Abstract BACKGROUND: Post-stroke immunosuppression elevates the risk of stroke-associated pneumonia (SAP). Our earlier research indicated that perihematomal neuron-derived PD-L1 may play a role in peripheral immunosuppression following intracerebral hemorrhage (ICH); however, the specific carriers of PD-L1 and its potential as a predictor for SAP risk are yet to be determined. MATERIALS AND METHODS: We hypothesize that elevated levels of exosomal PD-L1 in peripheral blood after ICH mediate immune suppression and increase the risk of SAP. This observational study aimed to investigate the levels of exosomal PD-L1 post-ICH and their relationship with SAP. In an exploratory cohort of 39 patients with ICH and 24 healthy controls and a validation cohort of 144 patients with ICH. RESULTS: At admission, patients with ICH exhibited significantly increased exosome numbers in their peripheral blood, with these exosomes showing high expression of the neuronal marker neural cell adhesion molecule L1, suggesting a brain origin. Exosomal PD-L1 levels were elevated in patients with ICH compared to healthy controls and were higher in patients with SAP than those without. After adjusting for confounders, exosomal PD-L1 was confirmed to be independently associated with SAP in both the exploratory cohort and validation cohort. CONCLUSIONS: Brain-derived exosomes with high expression of PD-L1 are substantially released into the periphery after ICH. Elevated exosomal PD-L1 levels correlate with an increased risk of SAP.

Presbycusis, or age-related hearing loss (ARHL), is a progressive condition that involves a steady decline in auditory function, primarily caused by the physiological alterations that occur with aging. This disorder arises from the combined effect of multiple interconnected factors that progressively affect the auditory system over time. Genome-wide association studies (GWAS) and transcriptomic analyses in human populations are valuable approaches for identifying potential genes associated with ARHL. This research seeks to assess the potential of protective drugs or strategies for treating ARHL by analyzing target gene-miRNA interactions identified in human blood and associated with presbycusis. We performed RNA sequencing to analyze the transcriptomes of peripheral blood leukocytes from ARHL patients. To identify genes associated with ARHL, the RNA-sequencing data from the peripheral blood leukocytes were compared and further validated by real-time polymerase chain reaction (RT-qPCR) using whole blood samples from the same ARHL patients. To explore the involvement of target genes and microRNAs (miRNAs) in ARHL, we examined miRNA expression patterns using RT-qPCR and reporter gene assays. We found that four genes were up-expressed in ARHL serum: Fas Ligand (FASLG), Neural Cell Adhesion Molecule 1 (NCAM1), Nectin Cell Adhesion Molecule 1 (NECTIN1), Macrophage Receptor with Collagenous Structure (MARCO). The up-expressed FASLG is associated with cell apoptosis and aging. Additionally, we showed that miR‑5195 and miR-3941 regulated FASLG expression in House Ear Institute-Organ of Corti 1 (HEI-OC-1) and HeLa cells via targeting of FASLG using luciferase reporter assays. Finally, the over-expression of the FASLG gene may be associated with the development of ARHL, and the inhibitory role of miR-5195 and miR-3941 could be a key factor in the prevention or protection against ARHL.

Stroke remains a leading cause of disability due to the brain’s limited ability to regenerate damaged neural circuits. Here, we show that local transplantation of iPSC-derived neural progenitor cells (NPCs) improves brain repair and long-term functional recovery in stroke-injured mice. NPCs survive for over five weeks, differentiate primarily into mature neurons, and contribute to regeneration-associated tissue responses including angiogenesis, blood–brain barrier repair, reduced inflammation, and neurogenesis. NPC-treated mice show improved gait and fine-motor recovery, as quantified by deep learning-based analysis. Single-nucleus RNA sequencing reveals that grafts predominantly adopt GABAergic and glutamatergic phenotypes, with GABAergic cells engaging in graft-host crosstalk via neurexin, neuregulin, neural cell adhesion molecule, and SLIT signaling pathways. Our findings provide mechanistic insight into how neural xenografts interact with host stroke tissue to drive structural and functional repair. These results support the therapeutic potential of NPC transplantation for promoting long-term recovery after stroke.

Genetic compensation highlights the importance of neural cell adhesion molecule Ncam1 paralogs in balancing signaling pathways during zebrafish lateral line development.

IntroductionExtrasynaptic GluN2B N-methyl-D-aspartate receptors (ES-GluN2B) are localized outside synapses and promote excitotoxic signaling, apoptosis, and long-term depression (LTD) in Alzheimer’s disease (AD). Polysialylated neural cell adhesion molecule (PSA-NCAM) physiologically inhibits ES-GluN2B activity, and its downregulation is associated with impaired synaptic plasticity. However, the spatiotemporal changes of ES-GluN2B and PSA-NCAM during brain aging versus AD remain poorly understood.MethodsWe investigated GluN2A, GluN2B, ES-GluN2B, and PSA-NCAM expression across brain regions in young and old Tg2576 AD and wild-type (WT) mice. Additional experiments included PSD-95 pulldown assays, analysis of GluN2B phosphorylation at Ser1480, CRISPRa-driven ST8Sia4 upregulation in IMR-32 neuroblastoma cells, and Aβ treatment to assess effects on PSA-NCAM biosynthetic enzymes.ResultsNormal aging was associated with decreased GluN2B, increased GluN2A, stable ES-GluN2B, and elevated PSA-NCAM levels. In contrast, AD aging showed elevated ES-GluN2B and reduced PSA-NCAM, particularly in the hippocampus and cortex, with no change in total NCAM expression. PSD-95 pulldown revealed increased extrasynaptic GluN2B in aged AD brains. AD aging was associated with elevated phosphorylation of GluN2B at Ser1480 by casein kinase 2 (CK2), promoting GluN2B redistribution to extrasynaptic sites. CRISPRa-driven ST8Sia4 upregulation increased PSA-NCAM and reduced pGluN2B expression supporting a direct regulatory role for PSA-NCAM in GluN2B trafficking. Additionally, Aβ suppressed PSA-NCAM biosynthetic enzymes ST8Sia4 and UDP-E linking Aβ to impaired polysialylation.DiscussionThese findings highlight distinct regulatory patterns of ES-GluN2B and PSA-NCAM in AD versus normal aging and support a model in which impaired PSA-NCAM buffering facilitates pathological ES-GluN2B signaling and plasticity loss in AD progression.

SummaryAssembly of cells into epithelial layers marks the early steps of tissue organization and embryonic development in most animals. Although several conserved proteins are known to be essential for epithelialization in bilaterians, it is unclear whether these are sufficient to drive epithelial organization in all metazoans. Using proteomics and knockdown approaches in embryos of the early-branching sea anemone Nematostella vectensis, we identified the neural cell adhesion molecule NCAM2 to be essential for organization of the primary epithelial layer. NCAM2 belongs to the immunoglobulin family of cell adhesion molecules with roles in inter-cellular adhesion and signaling. In this work, we show that NCAM2 is enriched at the apical cell junctions and is required for Nematostella epithelial cell identity. Importantly, embryos depleted for NCAM2 fail to gastrulate. Both whole-embryo germ layer patterning and tissue changes required for gastrulation are impaired. Together, our data show that in Nematostella NCAM2 is required for both epithelial and germ layer organization.

NCAM2 promotes targeting of APP from the cell surface to BACE1-containing recycling endosomes.

Reduced circulating NrCAM as a biomarker for fetal growth restriction

Secretagogin Downregulation Impairs Nerve Cell Migration in Hirschsprung Disease via Inhibition of the LEF-1/NCAM1 Axis

In membranous lupus nephritis (LN), positivity for the target antigen exostosin 1/2 (EXT) is associated with a lower chronicity index (CI) at first biopsy and a lower risk of progression to end-stage kidney disease (ESKD) compared to EXT-negative patients. Repeat kidney biopsies (RKB) in LN may reveal increasing CI and class transition with prognostic significance. In a cohort of membranous LN with RKB, we assessed the variation in EXT and neural cell adhesion molecule 1 (NCAM1) expression and their association with class III/IV + V transition and renal outcomes. Thirty patients with 78 biopsies were enrolled. Index biopsies included 60% EXT-NCAM1-, 34% EXT + NCAM1-, 3% EXT-NCAM1 + and 3% EXT + NCAM1 + cases. Target antigen switch occurred in 3 (10%) cases (2 EXT + to EXT-; 1 NCAM1- to NCAM1 +) with favorable renal outcomes. EXT-positive and EXT-negative groups had similar clinico-pathological characteristics at baseline and at the end of follow-up, with comparable numbers of RKB, median CI increase, class transition rates, and renal outcomes. After a median follow-up of 8.8years, 9 (32%) patients developed ESKD or glomerular filtration rate decrease > 40%. These patients exhibited higher median first biopsy CI (p = 0.04) and higher median serum creatinine level (p = 0.01), higher median CI (p = 0.02), and higher thrombotic microangiopathy (TMA) rate (p = 0.03) at second biopsy. TMA on any follow-up biopsy was more frequent in the adverse outcome group (p = 0.001). Not only EXT but also NCAM1 expression may vary in RKB during membranous LN. EXT-positive and EXT-negative patients had similar presentation and course, while TMA and CI compromised renal outcomes.