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1.
Elife ; 132024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38450720

RESUMO

Synapse is the fundamental structure for neurons to transmit information between cells. The proper synapse formation is crucial for developing neural circuits and cognitive functions of the brain. The aberrant synapse formation has been proved to cause many neurological disorders, including autism spectrum disorders and intellectual disability. Synaptic cell adhesion molecules (CAMs) are thought to play a major role in achieving mechanistic cell-cell recognition and initiating synapse formation via trans-synaptic interactions. Due to the diversity of synapses in different brain areas, circuits and neurons, although many synaptic CAMs, such as Neurexins (NRXNs), Neuroligins (NLGNs), Synaptic cell adhesion molecules (SynCAMs), Leucine-rich-repeat transmembrane neuronal proteins (LRRTMs), and SLIT and NTRK-like protein (SLITRKs) have been identified as synaptogenic molecules, how these molecules determine specific synapse formation and whether other molecules driving synapse formation remain undiscovered are unclear. Here, to provide a tool for synapse labeling and synaptic CAMs screening by artificial synapse formation (ASF) assay, we generated synaptotagmin-1-tdTomato (Syt1-tdTomato) transgenic mice by inserting the tdTomato-fused synaptotagmin-1 coding sequence into the genome of C57BL/6J mice. In the brain of Syt1-tdTomato transgenic mice, the tdTomato-fused synaptotagmin-1 (SYT1-tdTomato) signals were widely observed in different areas and overlapped with synapsin-1, a widely-used synaptic marker. In the olfactory bulb, the SYT1-tdTomato signals are highly enriched in the glomerulus. In the cultured hippocampal neurons, the SYT1-tdTomato signals showed colocalization with several synaptic markers. Compared to the wild-type (WT) mouse neurons, cultured hippocampal neurons from Syt1-tdTomato transgenic mice presented normal synaptic neurotransmission. In ASF assays, neurons from Syt1-tdTomato transgenic mice could form synaptic connections with HEK293T cells expressing NLGN2, LRRTM2, and SLITRK2 without immunostaining. Therefore, our work suggested that the Syt1-tdTomato transgenic mice with the ability to label synapses by tdTomato, and it will be a convenient tool for screening synaptogenic molecules.


Assuntos
Moléculas de Adesão Celular , Sinapses , Humanos , Camundongos , Animais , Camundongos Transgênicos , Células HEK293 , Camundongos Endogâmicos C57BL , Moléculas de Adesão Celular/metabolismo , Sinapses/fisiologia , Sinaptotagminas/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo
2.
Gen Physiol Biophys ; 43(1): 73-84, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38312036

RESUMO

This study investigated whether microbubbles activated by low-frequency ultrasound enhanced the anti-tumor effects of curcumin in glioma cells. CCK8 proliferation assay, scratch migration assay, and transwell invasion assay were performed to estimate the proliferation, migration, and invasion rates of the glioma cells in blank control and different treatment groups, respectively. Quantitative RT-PCR (qRT-PCR) analysis was performed to determine the relative expression levels of VEGF and NCAM mRNAs in the various experimental groups. Western blotting was performed to determine the activity status of the TGF-ß1/Smad signaling pathway in various groups of glioma cells by estimating the expression levels of p-SMAD2/3, VEGF, and NCAM proteins. Combined treatment (Cur-Us-MBs) with microbubbles activated by low-frequency ultrasound and curcumin significantly reduced the in vitro proliferation, migration, and invasiveness of glioma cells compared to the control and other treatment groups. Furthermore, Cur-Us-MBs significantly reduced the expression levels of VEGF and NCAM mRNAs and proteins and p-Smad2/3 proteins , including those cells stimulated with rhTGF-ß. These suggested that microbubbles activated by low-frequency ultrasound enhanced the inhibition of TGF-ß1/Smad/VEGF/NCAM signaling pathway by curcumin,and enhanced the antitumor effects of curcumin by significantly reducing in vitro proliferation, migration, and invasiveness of glioma cells through this pathway.


Assuntos
Curcumina , Glioma , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Curcumina/farmacologia , Glioma/tratamento farmacológico , Microbolhas , Moléculas de Adesão de Célula Nervosa/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas Smad/metabolismo
3.
J Chem Neuroanat ; 136: 102391, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38219812

RESUMO

BACKGROUND: Maternal diabetes during pregnancy can affect the neurological development of offspring. Glial cell-derived neurotrophic factor (GDNF), neurturin (NRTN), and neural cell adhesion molecules (NCAM) are three important proteins for brain development. Therefore, this study aimed to investigate the impacts of the mentioned neurotrophic factors in the hippocampal dentate gyrus (DG) of rat offspring born to diabetic mothers. METHODS: Wistar female rats were randomly allocated into diabetic (STZ-D) [(45 mg/kg BW, STZ (Streptozotocin), i.p)], diabetic + NPH insulin (STZ-INS) [(4-6 unit/kg/day SC)], and control groups. The animals in all groups were mated by non-diabetic male rats. Two weeks after birth, male pups from each group were sacrificed and then protein contents of GDNF, NRTN, and NCAM were evaluated using immunohistochemistry. RESULTS: The study found that the expression of GDNF and NRTN in the hippocampus of diabetic rat offspring was significantly higher compared to the diabetic+ insulin and control groups, respectively (P < 0.01, P < 0.001). Additionally, the expression of NCAM was significantly higher in the diabetic group the diabetic+ insulin and control groups (P < 0.01, P < 0.001). CONCLUSIONS: The results of the study revealed that diabetes during pregnancy significantly impacts the distribution pattern of GDNF, NRTN, and NCAM in the hippocampus of rat neonates.


Assuntos
Diabetes Gestacional , Insulinas , Humanos , Gravidez , Ratos , Animais , Masculino , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Neurturina/metabolismo , Neurturina/farmacologia , Ratos Wistar , Moléculas de Adesão de Célula Nervosa/metabolismo , Giro Denteado/metabolismo
4.
Transl Psychiatry ; 14(1): 31, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238328

RESUMO

Cognitive decline is a major health concern and identification of genes that may serve as drug targets to slow decline is important to adequately support an aging population. Whilst genetic studies of cross-sectional cognition have been carried out, cognitive change is less well-understood. Here, using data from the TOMMORROW trial, we investigate genetic associations with cognitive change in a cognitively normal older cohort. We conducted a genome-wide association study of trajectories of repeated cognitive measures (using generalised estimating equation (GEE) modelling) and tested associations with polygenic risk scores (PRS) of potential risk factors. We identified two genetic variants associated with change in attention domain scores, rs534221751 (p = 1 × 10-8 with slope 1) and rs34743896 (p = 5 × 10-10 with slope 2), implicating NCAM2 and CRIPT/ATP6V1E2 genes, respectively. We also found evidence for the association between an education PRS and baseline cognition (at >65 years of age), particularly in the language domain. We demonstrate the feasibility of conducting GWAS of cognitive change using GEE modelling and our results suggest that there may be novel genetic associations for cognitive change that have not previously been associated with cross-sectional cognition. We also show the importance of the education PRS on cognition much later in life. These findings warrant further investigation and demonstrate the potential value of using trial data and trajectory modelling to identify genetic variants associated with cognitive change.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Humanos , Idoso , Estudo de Associação Genômica Ampla , Estudos Transversais , Cognição , Disfunção Cognitiva/genética , Disfunção Cognitiva/psicologia , Moléculas de Adesão de Célula Nervosa/genética , Proteínas Adaptadoras de Transdução de Sinal/genética
5.
Cell Commun Signal ; 22(1): 85, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291468

RESUMO

K-Ras is the most frequently mutated Ras variant in pancreatic, colon and non-small cell lung adenocarcinoma. Activating mutations in K-Ras result in increased amounts of active Ras-GTP and subsequently a hyperactivation of effector proteins and downstream signaling pathways. Here, we demonstrate that oncogenic K-Ras(V12) regulates tumor cell migration by activating the phosphatidylinositol 3-kinases (PI3-K)/Akt pathway and induces the expression of E-cadherin and neural cell adhesion molecule (NCAM) by upregulation of Akt3. In vitro interaction and co-precipitation assays identified PI3-Kα as a bona fide effector of active K-Ras4B but not of H-Ras or N-Ras, resulting in enhanced Akt phosphorylation. Moreover, K-Ras(V12)-induced PI3-K/Akt activation enhanced migration in all analyzed cell lines. Interestingly, Western blot analyses with Akt isoform-specific antibodies as well as qPCR studies revealed, that the amount and the activity of Akt3 was markedly increased whereas the amount of Akt1 and Akt2 was downregulated in EGFP-K-Ras(V12)-expressing cell clones. To investigate the functional role of each Akt isoform and a possible crosstalk of the isoforms in more detail, each isoform was stably depleted in PANC-1 pancreatic and H23 lung carcinoma cells. Akt3, the least expressed Akt isoform in most cell lines, is especially upregulated and active in Akt2-depleted cells. Since expression of EGFP-K-Ras(V12) reduced E-cadherin-mediated cell-cell adhesion by induction of polysialylated NCAM, Akt3 was analyzed as regulator of E-cadherin and NCAM. Western blot analyses revealed pronounced reduction of E-cadherin and NCAM in the Akt3-kd cells, whereas Akt1 and Akt2 depletion upregulated E-cadherin, especially in H23 lung carcinoma cells. In summary, we identified oncogenic K-Ras4B as a key regulator of PI3-Kα-Akt signaling and Akt3 as a crucial regulator of K-Ras4B-induced modulation of E-cadherin and NCAM expression and localization.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Neoplasias Pancreáticas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Moléculas de Adesão de Célula Nervosa , Caderinas , Neoplasias Pulmonares/genética , Isoformas de Proteínas , Fosfatidilinositol 3-Quinases/metabolismo , Pulmão/metabolismo , Neoplasias Pancreáticas/patologia
6.
Mol Biotechnol ; 66(1): 90-101, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37031335

RESUMO

In the fight against glioblastoma, circular RNA is emerging as a functional molecule. However, how circular RNA (circRNA) is regulated and what role it plays is still a mystery. In this research, different bioinformatics approaches were used to evaluate glioblastoma circRNA sequencing and array data, with the goal of developing a putative molecular sponge mechanism control network. The circRNAs were obtained from the Gene Expression Omnibus datasets. MicroRNA-circRNA interactions were predicted using CircInteractome. The microRNAs' expression and survival trends were screened using the TCGA database. MicroRNA gene targets were predicted using the MiRnet database. Sponge network gene candidates were screened using data from the GEPIA. The roles of the targeted genes were to be explained by analyzing data from Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes. To build the network and display the outcomes, we utilized python program, and enrichment online Bioinformatics databases. The circRNAs hsa_circITGA4_002, hsa_circITGA4_001, hsa_circITGA4_003, hsa_circ_0030855, hsa_circ_0030857 were chosen from among GBM patients and control group. Upregulation of hsa-miR-1468, hsa-miR-3683, hsa-miR-1273c, and hsa-miR-4665-3p were associated with a poor prognosis in GBM. MicroRNA targets such as ITGA4, LAMA2, EGFR, PTEN, COL1A4, and NCAM2 were analyzed using expression and survival data. The Apoptosis, cell adhesion molecules, PI3K/AKT and P53 signaling pathways were the most abundant functional categories among gene targets. The circRNA molecular sponge regulatory network includes hsa-miR-1468 and hsa-miR-4665-3p. In this network, hs hsa_circITGA4_002, hsa_circITGA4_001, hsa_circ_0030857, EGFR, PTEN, and ITGA4 may represent GBM therapeutic targets. Their role in GBM needs additional study.


Assuntos
Glioblastoma , MicroRNAs , Humanos , RNA Circular/genética , Glioblastoma/genética , Fosfatidilinositol 3-Quinases , MicroRNAs/genética , MicroRNAs/metabolismo , Receptores ErbB/genética , Moléculas de Adesão de Célula Nervosa , PTEN Fosfo-Hidrolase/genética
7.
J Biomed Mater Res B Appl Biomater ; 112(1): e35310, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37950592

RESUMO

To provide a long-term solution for increasing the biocompatibility of neuroprosthetics, approaches to reduce the side effects of invasive neuro-implantable devices are still in need of improvement. Physical, chemical, and bioactive design aspects of the biomaterials are proven to be important for providing proper cell-to-cell, cell-to-material interactions. Particularly, modification of implant surfaces with bioactive cues, especially cell adhesion molecules (CAMs) that capitalize on native neural adhesion mechanisms, are promising candidates in favor of providing efficient interfaces. Within this concept, this study utilized specific CAMs, namely N-Cadherin (Neural cadherin, N-Cad) and neural cell adhesion molecule (NCAM), to enhance neuron-electrode contact by mimicking the cell-to-ECM interactions for improving the survival of cells and promoting neurite outgrowth. For this purpose, representative gold electrode surfaces were modified with N-Cadherin, NCAM, and the mixture (1:1) of these molecules. Modifications were characterized, and the effect of surface modification on both differentiated and undifferentiated neuroblastoma SH-SY5Y cell lines were compared. The findings demonstrated the successful modification of these molecules which subsequently exhibited biocompatible properties as evidenced by the cell viability results. In cell culture experiments, the CAMs displayed promising results in promoting neurite outgrowth compared to conventional poly-l-lysine coated surfaces, especially NCAM and N-Cad/NCAM modified surfaces clearly showed significant improvement. Overall, this optimized approach is expected to provide an insight into the action mechanisms of cells against the local environment and advance processes for the fabrication of alternative neural interfaces.


Assuntos
Neuritos , Neuroblastoma , Humanos , Neuritos/metabolismo , Neuroblastoma/metabolismo , Neurônios , Moléculas de Adesão Celular , Adesão Celular , Moléculas de Adesão de Célula Nervosa/metabolismo , Moléculas de Adesão de Célula Nervosa/farmacologia , Caderinas/metabolismo , Eletrodos
8.
J Biol Chem ; 300(1): 105564, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103644

RESUMO

The polysialyltransferases ST8SIA2 and ST8SIA4 and their product, polysialic acid (polySia), are known to be related to cancers and mental disorders. ST8SIA2 and ST8SIA4 have conserved amino acid (AA) sequence motifs essential for the synthesis of the polySia structures on the neural cell adhesion molecule. To search for a new motif in the polysialyltransferases, we adopted the in silico Individual Meta Random Forest program that can predict disease-related AA substitutions. The Individual Meta Random Forest program predicted a new eight-amino-acids sequence motif consisting of highly pathogenic AA residues, thus designated as the pathogenic (P) motif. A series of alanine point mutation experiments in the pathogenic motif (P motif) showed that most P motif mutants lost the polysialylation activity without changing the proper enzyme expression levels or localization in the Golgi. In addition, we evaluated the enzyme stability of the P motif mutants using newly established calculations of mutation energy, demonstrating that the subtle change of the conformational energy regulates the activity. In the AlphaFold2 model, we found that the P motif was a buried ß-strand underneath the known surface motifs unique to ST8SIA2 and ST8SIA4. Taken together, the P motif is a novel buried ß-strand that regulates the full activity of polysialyltransferases from the inside of the molecule.


Assuntos
Mutação , Sialiltransferases , Humanos , Motivos de Aminoácidos/genética , Substituição de Aminoácidos , Simulação por Computador , Complexo de Golgi/enzimologia , Complexo de Golgi/metabolismo , Moléculas de Adesão de Célula Nervosa/química , Moléculas de Adesão de Célula Nervosa/metabolismo , Mutação Puntual , Conformação Proteica em Folha beta , Transporte Proteico , Algoritmo Florestas Aleatórias , Ácidos Siálicos/metabolismo , Sialiltransferases/química , Sialiltransferases/genética , Sialiltransferases/metabolismo
9.
Arch Gerontol Geriatr ; 117: 105260, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37979338

RESUMO

OBJECTIVES: Exercise training plays a significant role in preventing the destruction of central nerve neurons and muscle atrophy. The purpose of the present study was to investigate the effect of a period of swimming training on the expression of Neural cell adhesion molecule (NCAM), Semaphorin 3A (SEMA3A), and Profilin-1 (PFN1) proteins in the gastrocnemius muscle of Alzheimer-like phenotype rats. METHODS & MATERIALS: 32 Wistar males were (6 weeks of age) divided into four groups: Healthy Control (HC), Alzheimer-like phenotype's Control (AC), Healthy Training (HT), and Alzheimer-like phenotype's Training (AT). Alzheimer-like phenotypes were induced by beta-amyloid injection in the hippocampus. The training program consisted of 20 swimming sessions. Gastrocnemius muscle was removed after the intervention, and NCAM, SEMA3A, and PFN1 proteins were measured by the immunohistoflorescent method. RESULTS: The results showed that SEMA3A was increased (p = 0.001), and NCAM (p = 0.001), and PFN1 (p = 0.001) were decreased in AC compared to the HC group. Also, the results showed that NCAM (p = 0.001) and Pfn1 (p = 0.002) increased in the HT group compared to HC, and the NCAM (p = 0.001) and Pfn1 (p = 0.002) in AT group compared to AC (p = 0.001) increased significantly, while SEMA3A was reduced in the HT group compared to HC (p = 0.001) and AT group compared to AC (p = 0.001) CONCLUSION: Swimming effectively improves axon regeneration and neuronal formation in motor neurons and, therefore, can be an effective intervention to prevent and control the complications of Alzheimer-like phenotype.


Assuntos
Doença de Alzheimer , Natação , Masculino , Humanos , Ratos , Animais , Ratos Wistar , Natação/fisiologia , Semaforina-3A/genética , Semaforina-3A/metabolismo , Semaforina-3A/farmacologia , Axônios/metabolismo , Regeneração Nervosa , Músculo Esquelético/metabolismo , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Moléculas de Adesão de Célula Nervosa/farmacologia , Profilinas/farmacologia
10.
Prog Neurobiol ; 232: 102560, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38097036

RESUMO

Damaged or dysfunctional neural circuits can be replaced after a lesion by axon sprouting and collateral growth from undamaged neurons. Unfortunately, these new connections are often disorganized and rarely produce clinical improvement. Here we investigate how to promote post-lesion axonal collateral growth, while retaining correct cellular targeting. In the mouse olivocerebellar path, brain-derived neurotrophic factor (BDNF) induces correctly-targeted post-lesion cerebellar reinnervation by remaining intact inferior olivary axons (climbing fibers). In this study we identified cellular processes through which BDNF induces this repair. BDNF injection into the denervated cerebellum upregulates the transcription factor Pax3 in inferior olivary neurons and induces rapid climbing fiber sprouting. Pax3 in turn increases polysialic acid-neural cell adhesion molecule (PSA-NCAM) in the sprouting climbing fiber path, facilitating collateral outgrowth and pathfinding to reinnervate the correct targets, cerebellar Purkinje cells. BDNF-induced reinnervation can be reproduced by olivary Pax3 overexpression, and abolished by olivary Pax3 knockdown, suggesting that Pax3 promotes axon growth and guidance through upregulating PSA-NCAM, probably on the axon's growth cone. These data indicate that restricting growth-promotion to potential reinnervating afferent neurons, as opposed to stimulating the whole circuit or the injury site, allows axon growth and appropriate guidance, thus accurately rebuilding a neural circuit.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Moléculas de Adesão de Célula Nervosa , Animais , Camundongos , Axônios/fisiologia , Cerebelo
11.
Cells ; 12(21)2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37947603

RESUMO

Cannabis is now one of the most commonly used illicit substances among pregnant women. This is particularly concerning since developmental exposure to cannabinoids can elicit enduring neurofunctional and cognitive alterations. This study investigates the mechanisms of learning and memory deficits resulting from prenatal cannabinoid exposure (PCE) in adolescent offspring. The synthetic cannabinoid agonist WIN55,212-2 was administered to pregnant rats, and a series of behavioral, electrophysiological, and immunochemical studies were performed to identify potential mechanisms of memory deficits in the adolescent offspring. Hippocampal-dependent memory deficits in adolescent PCE animals were associated with decreased long-term potentiation (LTP) and enhanced long-term depression (LTD) at hippocampal Schaffer collateral-CA1 synapses, as well as an imbalance between GluN2A- and GluN2B-mediated signaling. Moreover, PCE reduced gene and protein expression of neural cell adhesion molecule (NCAM) and polysialylated-NCAM (PSA-NCAM), which are critical for GluN2A and GluN2B signaling balance. Administration of exogenous PSA abrogated the LTP deficits observed in PCE animals, suggesting PSA mediated alterations in GluN2A- and GluN2B- signaling pathways may be responsible for the impaired hippocampal synaptic plasticity resulting from PCE. These findings enhance our current understanding of how PCE affects memory and how this process can be manipulated for future therapeutic purposes.


Assuntos
Canabinoides , Moléculas de Adesão de Célula Nervosa , Humanos , Ratos , Feminino , Animais , Gravidez , Adolescente , Moléculas de Adesão de Célula Nervosa/metabolismo , Canabinoides/farmacologia , Canabinoides/metabolismo , Plasticidade Neuronal/fisiologia , Hipocampo/metabolismo , Transtornos da Memória/metabolismo
12.
Bioorg Chem ; 140: 106828, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37690368

RESUMO

In drug discovery and development, the direct target identification of bioactive small molecules plays a significant role for understanding the mechanism of action, predicting the side effects, and rationally designing more potent compounds. However, due to the complicated regulatory processes in a cell together with thousands of biomacromolecules, target identification is always the major obstacle. New methods and technologies are continuously invented to tackle this problem. Nevertheless, the mainly used tools possess several disadvantages. High synthetic skills are typically required to laboriously synthesize a probe for protein enrichment. To detect the ligand-protein interaction by analyzing proteins' responses to proteolytic or thermal treatment, costly and precise instruments are always necessary. Therefore, convenient and practical techniques are urgently needed. Over the past decades, a strategy using native compounds without the requirement of chemical modification, also termed Native-compound-Coupled Affinity Matrix (NCAM), is developing continuously. Two practical tactics based on "label-free" compounds have been invented and used, that is Photo-cross-linked Small-molecule Affinity Matrix (PSAM) and Native-compound-Coupled CNBr-activated Beads (NCCB). Presently, we will elucidate the characteristics, coupling mechanism, advantages and disadvantages, and future prospect of NCAM in specific target identification and validation.


Assuntos
Descoberta de Drogas , Peptídeo Hidrolases , Proteólise , Moléculas de Adesão de Célula Nervosa
13.
Sci Adv ; 9(37): eadi3647, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713494

RESUMO

Neuron-derived extracellular vesicles (NDEVs) are potential biomarkers of neurological diseases although their reliable molecular target is not well established. Here, we demonstrate that ATPase Na+/K+ transporting subunit alpha 3 (ATP1A3) is abundantly expressed in extracellular vesicles (EVs) isolated from induced human neuron, brain, cerebrospinal fluid, and plasma in comparison with the presumed NDEV markers NCAM1 and L1CAM by using super-resolution microscopy and biochemical assessments. Proteomic analysis of immunoprecipitated ATP1A3+ brain-derived EVs shows higher enrichment of synaptic markers and cargo proteins relevant to Alzheimer's disease (AD) compared to NCAM1+ or LICAM+ EVs. Single particle analysis shows the elevated amyloid-ß positivity in ATP1A3+ EVs from AD plasma, providing better diagnostic prediction of AD over other plasma biomarkers. Thus, ATP1A3 is a reliable target to isolate NDEV from biofluids for diagnostic research.


Assuntos
Doença de Alzheimer , Vesículas Extracelulares , Humanos , Proteômica , Encéfalo , Moléculas de Adesão de Célula Nervosa , Neurônios , ATPase Trocadora de Sódio-Potássio
14.
Cereb Cortex ; 33(21): 10931-10948, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37724425

RESUMO

Adult neurogenesis persists in mammals in the neurogenic zones, where newborn neurons are incorporated into preexisting circuits to preserve and improve learning and memory tasks. Relevant structural elements of the neurogenic niches include the family of cell adhesion molecules (CAMs), which participate in signal transduction and regulate the survival, division, and differentiation of radial glial progenitors (RGPs). Here we analyzed the functions of neural cell adhesion molecule 2 (NCAM2) in the regulation of RGPs in adult neurogenesis and during corticogenesis. We characterized the presence of NCAM2 across the main cell types of the neurogenic process in the dentate gyrus, revealing different levels of NCAM2 amid the progression of RGPs and the formation of neurons. We showed that Ncam2 overexpression in adult mice arrested progenitors in an RGP-like state, affecting the normal course of young-adult neurogenesis. Furthermore, changes in Ncam2 levels during corticogenesis led to transient migratory deficits but did not affect the survival and proliferation of RGPs, suggesting a differential role of NCAM2 in adult and embryonic stages. Our data reinforce the relevance of CAMs in the neurogenic process by revealing a significant role of Ncam2 levels in the regulation of RGPs during young-adult neurogenesis in the hippocampus.


Assuntos
Neurogênese , Neurônios , Camundongos , Animais , Neurônios/fisiologia , Neurogênese/fisiologia , Diferenciação Celular/fisiologia , Moléculas de Adesão de Célula Nervosa/metabolismo , Hipocampo/metabolismo , Mamíferos/metabolismo
15.
Int J Biol Macromol ; 247: 125756, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37429340

RESUMO

Neural cell adhesion molecules (NCAMs) are large cell-surface glycoproteins playing important roles in cell-cell and cell-extracellular matrix interactions in nervous system. Recent study identified a homologue of NCAM (CgNCAM) from the Pacific oyster Crassostrea gigas. Its ORF was of 2634 bp which encodes a protein (877 amino acids) consisting of five immunoglobulin domains and two fibronectin type III domains. CgNCAM transcripts were broadly distributed in oyster tissues especially in mantle, labial palp and haemolymph. CgNCAM showed up-regulated expression in haemocytes of oysters after Vibrio splendidus and Staphylococcus aureus stimulation. The recombinant CgNCAM protein (rCgNCAM) was able to bind manose, lipopolysaccharide and glucan, as well as different microbes including Gram-negative bacteria and fungi. rCgNCAM displayed bacterial agglutination and hemagglutination activity. CgNCAM improved the phagocytosis of haemocytes towards V. splendidus by regulating the expression of CgIntegrin, CgRho J and CgMAPKK. Moreover, CgNCAM was involved in the extracellular trap establishment of haemocytes after V. splendidus stimulation. The results collectively indicated that CgNCAM acted as a recognition receptor executing multiple immune functions to recognize and eliminate invading microorganisms in innate immunity of oysters.


Assuntos
Crassostrea , Animais , Crassostrea/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Imunidade Inata , Fagocitose , Bactérias Gram-Negativas , Proteínas Recombinantes/metabolismo , Hemócitos/microbiologia
16.
Cereb Cortex ; 33(18): 10047-10065, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37522285

RESUMO

The neural cell adhesion molecule 2 (NCAM2) regulates axonal organization in the central nervous system via mechanisms that have remained poorly understood. We now show that NCAM2 increases axonal levels of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), a protease that regulates axonal guidance. In brains of NCAM2-deficient mice, BACE1 levels are reduced in hippocampal mossy fiber projections, and the infrapyramidal bundle of these projections is shortened. This abnormal axonal organization correlates with impaired short-term spatial memory and cognitive flexibility in NCAM2-deficient male and female mice. Self-grooming, rearing, digging and olfactory acuity are increased in NCAM2-deficient male mice, when compared with littermate wild-type mice of the same sex. NCAM2-deficient female mice also show increased self-grooming, but are reduced in rearing, and do not differ from female wild-type mice in olfactory acuity and digging behavior. Our results indicate that errors in axonal guidance and organization caused by impaired BACE1 function can underlie the manifestation of neurodevelopmental disorders, including autism as found in humans with deletions of the NCAM2 gene.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Animais , Feminino , Humanos , Masculino , Camundongos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Hipocampo/metabolismo , Fibras Musgosas Hipocampais , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo
17.
Behav Brain Res ; 452: 114590, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37499910

RESUMO

Synaptic dysfunction underlies many neurodevelopmental disorders (NDDs). The membrane-associated mucin domain-containing glycosylphosphatidylinositol anchor proteins (MDGAs) regulate synaptic development by modulating neurexin-neuroligin complex formation. Since understanding the neurodevelopmental profile and the sex-based differences in the manifestation of the symptoms of NDDs is important for their early diagnosis, we tested a mouse model haploinsufficient for MDGA2 (MDGA2+/-) on a neurodevelopmental test battery, containing sensory, motor, and cognitive measures, as well as ultrasonic vocalizations. When male and female MDGA2+/- and wildtype (WT) C57BL/6 J mice were examined from 2 to 23 days of age using this test battery, genotype and sex differences in body weight, sensory-motor processes, and ultrasonic vocalizations were observed. The auditory startle reflex appeared earlier in the MDGA2+/- than in WT mice and the MDGA2+/- mice produced fewer ultrasonic vocalizations. The MDGA2+/- mice showed reduced locomotion and rearing than WT mice in the open field after 17 days of age and spent less time investigating a novel object than WT mice at 21 days of age. Female MDGA2+/- mice weighed less than WT females and showed lower grip strength, indicating a delay in sensory-motor development in MDGA2+/- mice, which appears to be more pronounced in females than males. The behavioural phenotypes resulting from MDGA2 haploinsufficiency suggests that it shows delayed development of motor behaviour, grip strength and exploratory behaviour, non-social phenotypes of NDDs.


Assuntos
Transtornos do Neurodesenvolvimento , Camundongos , Feminino , Masculino , Animais , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Proteínas de Membrana , Reflexo de Sobressalto , Moléculas de Adesão de Célula Nervosa/metabolismo , Proteínas Ligadas por GPI/metabolismo
18.
Cell Biochem Biophys ; 81(3): 533-542, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37470932

RESUMO

Mucopolysaccharidosis type II (MPS II) is a disorder caused by a deficient activity of iduronate-2-sulfatase, a lysosomal enzyme responsible for degrading glycosaminoglycans (GAGs). The abnormal storage of GAGs within lysosomes disrupts cellular homeostasis and leads to a severe symptomatology. Patients present neuropsychiatric impairment characterized by mental retardation and impaired cognition. The aim of this study was to quantify four neurodegeneration biomarkers in plasma: brain-derived neurotrophic factor (BDNF), platelet-derived growth factor (PDGF-AA), neural cell adhesion molecule (NCAM) and cathepsin-D, as well as to identify possible correlations with urinary GAGs in seven patients undergoing treatment with ERT (Elaprase® 0.5 mg/kg of body weight). Patients with both severe and attenuated forms of MPS II showed signs of neurodegeneration in neuroimaging exams. Patients have a decrease in BDNF and PDGF-AA concentrations, and an increase in NCAM level compared to controls. No alterations in cathepsin-D concentration were seen. GAGs levels were higher in patients than in controls, but no significant correlations between GAGs and biomarkers were observed. These results evidence that patients have neurodegeneration and that monitoring these biomarkers might be useful for assessing this process. To this date, this is the first work to analyze these plasmatic markers of neurodegeneration in patients.


Assuntos
Mucopolissacaridose II , Humanos , Mucopolissacaridose II/complicações , Mucopolissacaridose II/tratamento farmacológico , Mucopolissacaridose II/diagnóstico , Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Terapia de Reposição de Enzimas , Glicosaminoglicanos/metabolismo , Glicosaminoglicanos/uso terapêutico , Biomarcadores , Moléculas de Adesão de Célula Nervosa/uso terapêutico
19.
Cell Rep ; 42(7): 112714, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37384525

RESUMO

Neurexin synaptic organizing proteins are central to a genetic risk pathway in neuropsychiatric disorders. Neurexins also exemplify molecular diversity in the brain, with over a thousand alternatively spliced forms and further structural heterogeneity contributed by heparan sulfate glycan modification. Yet, interactions between these modes of post-transcriptional and post-translational modification have not been studied. We reveal that these regulatory modes converge on neurexin-1 splice site 5 (S5): the S5 insert increases the number of heparan sulfate chains. This is associated with reduced neurexin-1 protein level and reduced glutamatergic neurotransmitter release. Exclusion of neurexin-1 S5 in mice boosts neurotransmission without altering the AMPA/NMDA ratio and shifts communication and repetitive behavior away from phenotypes associated with autism spectrum disorders. Thus, neurexin-1 S5 acts as a synaptic rheostat to impact behavior through the intersection of RNA processing and glycobiology. These findings position NRXN1 S5 as a potential therapeutic target to restore function in neuropsychiatric disorders.


Assuntos
Processamento Alternativo , Transtorno Autístico , Animais , Camundongos , Processamento Alternativo/genética , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Encéfalo/metabolismo , Heparitina Sulfato/metabolismo , Moléculas de Adesão de Célula Nervosa/genética , Sinapses/metabolismo , Transmissão Sináptica
20.
Nat Commun ; 14(1): 3770, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355690

RESUMO

De novo mutations and copy number deletions in NRXN1 (2p16.3) pose a significant risk for schizophrenia (SCZ). It is unclear how NRXN1 deletions impact cortical development in a cell type-specific manner and disease background modulates these phenotypes. Here, we leveraged human pluripotent stem cell-derived forebrain organoid models carrying NRXN1 heterozygous deletions in isogenic and SCZ patient genetic backgrounds and conducted single-cell transcriptomic analysis over the course of brain organoid development from 3 weeks to 3.5 months. Intriguingly, while both deletions similarly impacted molecular pathways associated with ubiquitin-proteasome system, alternative splicing, and synaptic signaling in maturing glutamatergic and GABAergic neurons, SCZ-NRXN1 deletions specifically perturbed developmental trajectories of early neural progenitors and accumulated disease-specific transcriptomic signatures. Using calcium imaging, we found that both deletions led to long-lasting changes in spontaneous and synchronous neuronal networks, implicating synaptic dysfunction. Our study reveals developmental-timing- and cell-type-dependent actions of NRXN1 deletions in unique genetic contexts.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/genética , Organoides , Prosencéfalo , Citoplasma , Complexo de Endopeptidases do Proteassoma , Proteínas de Ligação ao Cálcio/genética , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão Celular Neuronais/genética
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