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1.
Nat Commun ; 15(1): 3173, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609390

RESUMO

Semaphorin-3A (SEMA3A) functions as a chemorepulsive signal during development and can affect T cells by altering their filamentous actin (F-actin) cytoskeleton. The exact extent of these effects on tumour-specific T cells are not completely understood. Here we demonstrate that Neuropilin-1 (NRP1) and Plexin-A1 and Plexin-A4 are upregulated on stimulated CD8+ T cells, allowing tumour-derived SEMA3A to inhibit T cell migration and assembly of the immunological synapse. Deletion of NRP1 in both CD4+ and CD8+ T cells enhance CD8+ T-cell infiltration into tumours and restricted tumour growth in animal models. Conversely, over-expression of SEMA3A inhibit CD8+ T-cell infiltration. We further show that SEMA3A affects CD8+ T cell F-actin, leading to inhibition of immune synapse formation and motility. Examining a clear cell renal cell carcinoma patient cohort, we find that SEMA3A expression is associated with reduced survival, and that T-cells appear trapped in SEMA3A rich regions. Our study establishes SEMA3A as an inhibitor of effector CD8+ T cell tumour infiltration, suggesting that blocking NRP1 could improve T cell function in tumours.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Animais , Humanos , Actinas , Linfócitos T CD8-Positivos , Citoesqueleto , Semaforina-3A/genética
2.
J Cell Mol Med ; 28(8): e18201, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38568078

RESUMO

Sensory nerves play a crucial role in maintaining bone homeostasis by releasing Semaphorin 3A (Sema3A). However, the specific mechanism of Sema3A in regulation of bone marrow mesenchymal stem cells (BMMSCs) during bone remodelling remains unclear. The tibial denervation model was used and the denervated tibia exhibited significantly lower mass as compared to sham operated bones. In vitro, BMMSCs cocultured with dorsal root ganglion cells (DRGs) or stimulated by Sema3A could promote osteogenic differentiation through the Wnt/ß-catenin/Nrp1 positive feedback loop, and the enhancement of osteogenic activity could be inhibited by SM345431 (Sema3A-specific inhibitor). In addition, Sema3A-stimulated BMMSCs or intravenous injection of Sema3A could promote new bone formation in vivo. To sum up, the coregulation of bone remodelling is due to the ageing of BMMSCs and increased osteoclast activity. Furthermore, the sensory neurotransmitter Sema3A promotes osteogenic differentiation of BMMSCs via Wnt/ß-catenin/Nrp1 positive feedback loop, thus promoting osteogenesis in vivo and in vitro.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Osteogênese/genética , Semaforina-3A/genética , Retroalimentação , beta Catenina , Gânglios Espinais , Neuropilina-1/genética
3.
Cell Biochem Funct ; 42(3): e4012, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584583

RESUMO

Osteoarthritis (OA) is characterised by the deterioration of cartilage in the joints and pain. We hypothesise that semaphorin-3A (sema-3A), a chemorepellent for sensory nerves, plays a role in joint degradation and pain. We used the mechanical joint loading (MJL) model of OA to investigate sema-3A expression in the joint and examine its association with the development of OA and pain. We also analyse its effect on chondrocyte differentiation using the ATDC5 cell line. We demonstrate that sema-3A is present in most tissues in the healthy joint and its expression increases in highly innervated tissues, such as cruciate ligaments, synovial lining and subchondral bone, in loaded compared to nonloaded control joints. In contrast, sema-3A expression in cartilage was decreased in the severe OA induced by the application of high loads. There was a significant increase in circulating sema-3A, 6 weeks after MJL compared to the nonloaded mice. mRNA for sema-3A and its receptor Plexin A1 were upregulated in the dorsal root ganglia of mice submitted to MJL. These increases were supressed by zoledronate, an inhibitor of bone pain. Sema-3A was expressed at all stages of Chondrocyte maturation and, when added exogenously, stimulated expression of markers of chondrocyte differentiation. This indicates that sema-3A could affect joint tissues distinctively during the development of OA. In highly innervated joint tissues, sema-3A could control innervation and/or induce pain-associated neuronal changes. In cartilage, sema-3A could favour its degeneration by modifying chondrocyte differentiation.


Assuntos
Osso e Ossos , Semaforina-3A , Animais , Camundongos , Osso e Ossos/metabolismo , Diferenciação Celular , Linhagem Celular , Dor , Semaforina-3A/genética , Semaforina-3A/metabolismo
4.
Neuromolecular Med ; 26(1): 13, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619671

RESUMO

Normal tension glaucoma (NTG) is a progressive neurodegenerative disease in glaucoma families. Typical glaucoma develops because of increased intraocular pressure (IOP), whereas NTG develops despite normal IOP. As a subtype of open-angle glaucoma, NTG is characterized by retinal ganglion cell (RGC) degeneration, gradual loss of axons, and injury to the optic nerve. The relationship between glutamate excitotoxicity and oxidative stress has elicited great interest in NTG studies. We recently reported that suppressing collapsin response mediator protein 2 (CRMP2) phosphorylation in S522A CRMP2 mutant (CRMP2 KIKI) mice inhibited RGC death in NTG mouse models. This study evaluated the impact of the natural compounds huperzine A (HupA) and naringenin (NAR), which have therapeutic effects against glutamate excitotoxicity and oxidative stress, on inhibiting CMRP2 phosphorylation in mice intravitreally injected with N-methyl-D-aspartate (NMDA) and GLAST mutant mice. Results of the study demonstrated that HupA and NAR significantly reduced RGC degeneration and thinning of the inner retinal layer, and inhibited the elevated CRMP2 phosphorylation. These treatments protected against glutamate excitotoxicity and suppressed oxidative stress, which could provide insight into developing new effective therapeutic strategies for NTG.


Assuntos
Alcaloides , Glaucoma de Ângulo Aberto , Glaucoma , Glaucoma de Baixa Tensão , Doenças Neurodegenerativas , Sesquiterpenos , Animais , Camundongos , Modelos Animais de Doenças , Glaucoma/tratamento farmacológico , Ácido Glutâmico/toxicidade , Fosforilação , Células Ganglionares da Retina , Semaforina-3A
5.
Cell Mol Biol (Noisy-le-grand) ; 70(2): 244-249, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38430015

RESUMO

Osteoarthritis (OA) is a major disease that causes disability in middle-aged and elderly people. A comprehensive understanding of its pathogenesis is of great significance in finding new clinical diagnosis and treatment schemes. The role of Semaphorin 3A (Sema3A) in OS has attracted attention recently, and the purpose of this study is to analyze the mechanisms underlying its impact on OS. First, a rat model of OS was established. Hematoxylin-eosin (HE) and TUNEL staining showed that the modeled rats presented typical pathological manifestations of OS, confirming the success of the modeling. Sema3A was significantly underexpressed in OS rats. Subsequently, Sema3A abnormal expression vectors were constructed to intervene in chondrocytes isolated from OS rats. It was found that the proliferation of chondrocytes was decreased, the apoptosis was increased, and the mitochondrial damage and autophagy were intensified after silencing Sema3A expression, while the above pathological processes were reversed when Sema3A expression was increased. In conclusion, Sema3A has an important influence on the pathological progression of OS, and molecular therapies targeting to increase Sema3A expression may become a new treatment for OS in the future.


Assuntos
Osteoartrite , Semaforina-3A , Animais , Ratos , Apoptose/genética , Condrócitos/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Semaforina-3A/genética , Semaforina-3A/metabolismo
6.
Neurobiol Dis ; 194: 106466, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38471625

RESUMO

In recent studies, brain stimulation has shown promising potential to alleviate chronic pain. Although studies have shown that stimulation of pain-related brain regions can induce pain-relieving effects, few studies have elucidated the mechanisms of brain stimulation in the insular cortex (IC). The present study was conducted to explore the changes in characteristic molecules involved in pain modulation mechanisms and to identify the changes in synaptic plasticity after IC stimulation (ICS). Following ICS, pain-relieving behaviors and changes in proteomics were explored. Neuronal activity in the IC after ICS was observed by optical imaging. Western blotting was used to validate the proteomics data and identify the changes in the expression of glutamatergic receptors associated with synaptic plasticity. Experimental results showed that ICS effectively relieved mechanical allodynia, and proteomics identified specific changes in collapsin response mediator protein 2 (CRMP2). Neuronal activity in the neuropathic rats was significantly decreased after ICS. Neuropathic rats showed increased expression levels of phosphorylated CRMP2, alpha amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR), and N-methyl-d-aspartate receptor (NMDAR) subunit 2B (NR2B), which were inhibited by ICS. These results indicate that ICS regulates the synaptic plasticity of ICS through pCRMP2, together with AMPAR and NR2B, to induce pain relief.


Assuntos
Neuralgia , Receptores de N-Metil-D-Aspartato , Semaforina-3A , Animais , Ratos , Hiperalgesia , Córtex Insular , Neuralgia/terapia , Neuralgia/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Semaforina-3A/metabolismo
7.
Nat Commun ; 15(1): 1962, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438384

RESUMO

Myelinated axons form long-range connections that enable rapid communication between distant brain regions, but how genetics governs the strength and organization of these connections remains unclear. We perform genome-wide association studies of 206 structural connectivity measures derived from diffusion magnetic resonance imaging tractography of 26,333 UK Biobank participants, each representing the density of myelinated connections within or between a pair of cortical networks, subcortical structures or cortical hemispheres. We identify 30 independent genome-wide significant variants after Bonferroni correction for the number of measures studied (126 variants at nominal genome-wide significance) implicating genes involved in myelination (SEMA3A), neurite elongation and guidance (NUAK1, STRN, DPYSL2, EPHA3, SEMA3A, HGF, SHTN1), neural cell proliferation and differentiation (GMNC, CELF4, HGF), neuronal migration (CCDC88C), cytoskeletal organization (CTTNBP2, MAPT, DAAM1, MYO16, PLEC), and brain metal transport (SLC39A8). These variants have four broad patterns of spatial association with structural connectivity: some have disproportionately strong associations with corticothalamic connectivity, interhemispheric connectivity, or both, while others are more spatially diffuse. Structural connectivity measures are highly polygenic, with a median of 9.1 percent of common variants estimated to have non-zero effects on each measure, and exhibited signatures of negative selection. Structural connectivity measures have significant genetic correlations with a variety of neuropsychiatric and cognitive traits, indicating that connectivity-altering variants tend to influence brain health and cognitive function. Heritability is enriched in regions with increased chromatin accessibility in adult oligodendrocytes (as well as microglia, inhibitory neurons and astrocytes) and multiple fetal cell types, suggesting that genetic control of structural connectivity is partially mediated by effects on myelination and early brain development. Our results indicate pervasive, pleiotropic, and spatially structured genetic control of white-matter structural connectivity via diverse neurodevelopmental pathways, and support the relevance of this genetic control to healthy brain function.


Assuntos
Conectoma , Adulto , Humanos , Estudo de Associação Genômica Ampla , Semaforina-3A , Genes Reguladores , Encéfalo/diagnóstico por imagem , Proteínas Quinases , Proteínas Repressoras , Proteínas dos Microfilamentos , Peptídeos e Proteínas de Sinalização Intracelular
8.
Neurosci Lett ; 824: 137691, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38373630

RESUMO

Enhancing axonal regeneration is one of the most important processes in treating nerve injuries. Both magnetic and electrical stimulation have the effect of promoting nerve axon regeneration. But few study has investigated the effects of trans-spinal magnetic stimulation (TsMS) combined with electroacupuncture (EA) on nerve regeneration in rats with sciatic nerve injury. In this study, we compared the improvement of neurological function in rats with sciatic nerve crush injuries after 4 weeks of different interventions (EA, TsMS, or TsMS combined with EA). We further explored the morphological and molecular biological alterations following sciatic nerve injury by HE, Masson, RT-PCR, western blotting, immunofluorescence staining and small RNA transcriptome sequencing. The results showed that TsMS combined with EA treatment significantly promoted axonal regeneration, increased the survival rate of neurons, and suppressed denervation atrophy of the gastrocnemius muscle. Subsequent experiments suggested that the combination treatment may play an active role by mediating the miR-539-5p/Sema3A/PlexinA1 signaling axis.


Assuntos
Eletroacupuntura , MicroRNAs , Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Ratos , Animais , Ratos Sprague-Dawley , Semaforina-3A/farmacologia , Axônios , Regeneração Nervosa/fisiologia , Nervo Isquiático/lesões , Neuropatia Ciática/terapia , Traumatismos dos Nervos Periféricos/terapia , MicroRNAs/genética , MicroRNAs/farmacologia
9.
J Zhejiang Univ Sci B ; 25(1): 38-50, 2024 Jan 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38163665

RESUMO

Gorham-Stout disease (GSD) is a sporadic chronic disease characterized by progressive bone dissolution, absorption, and disappearance along with lymphatic vessel infiltration in bone-marrow cavities. Although the osteolytic mechanism of GSD has been widely studied, the cause of lymphatic hyperplasia in GSD is rarely investigated. In this study, by comparing the RNA expression profile of osteoclasts (OCs) with that of OC precursors (OCPs) by RNA sequencing, we identified a new factor, semaphorin 3A (Sema3A), which is an osteoprotective factor involved in the lymphatic expansion of GSD. Compared to OCPs, OCs enhanced the growth, migration, and tube formation of lymphatic endothelial cells (LECs), in which the expression of Sema3A is low compared to that in OCPs. In the presence of recombinant Sema3A, the growth, migration, and tube formation of LECs were inhibited, further confirming the inhibitory effect of Sema3A on LECs in vitro. Using an LEC-induced GSD mouse model, the effect of Sema3A was examined by injecting lentivirus-expressing Sema3A into the tibiae in vivo. We found that the overexpression of Sema3A in tibiae suppressed the expansion of LECs and alleviated bone loss, whereas the injection of lentivirus expressing Sema3A short hairpin RNA (shRNA) into the tibiae caused GSD-like phenotypes. Histological staining further demonstrated that OCs decreased and osteocalcin increased after Sema3A lentiviral treatment, compared with the control. Based on the above results, we propose that reduced Sema3A in OCs is one of the mechanisms contributing to the pathogeneses of GSD and that expressing Sema3A represents a new approach for the treatment of GSD.


Assuntos
Vasos Linfáticos , Osteólise Essencial , Semaforina-3A , Animais , Camundongos , Células Endoteliais/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteólise Essencial/metabolismo , Osteólise Essencial/patologia , Semaforina-3A/metabolismo
10.
Sci Rep ; 14(1): 1969, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263416

RESUMO

Breast cancer is a major health concern, and its accurate diagnosis and management depend on identifying its histological type and biological subtype. Semaphorin-3A (SEMA3A) is a membrane protein with diverse roles in cellular processes, including cancer progression and angiogenesis regulation. However, its role in breast cancer remains poorly understood. This study aimed to evaluate SEMA3A expression in breast cancer and investigate its distribution across breast cancer subtypes: luminal A, luminal B, HER2-positive, and triple-negative breast cancer (TNBC). Immunohistochemical evaluation was performed on 98 breast cancer patients' tumor specimens, and SEMA3A expression was assessed in tumor cells and vessels. The study included the analysis of the Ki67 proliferation index, estrogen receptor (ER) expression, progesterone receptor (PR) expression, and HER2 status in conjunction with SEMA3A expression. Analysis indicated positive expression of SEMA3A in breast cancer cells in 60 out of 98 cases. SEMA3A expression correlated positively with Ki67 levels in tumor cells (p = 0.0005, R Spearman 0.338). Notably, a negative correlation was found between SEMA3A expression and ER and PR levels in tumor cells (p = 0.04, Spearman's R = - 0.21 and p = 0.016, Spearman's R = - 0.25 respectively). HER2 status did not significantly influence SEMA3A expression. The study demonstrated positive SEMA3A expression in tumor vessels across all subtypes in 91 out of 98 cases, suggesting its involvement in endothelial cell function. However, no significant differences in SEMA3A expression were observed between breast cancer subtypes either in vessels or tumor cells. These findings suggest that elevated SEMA3A expression may be associated with worse prognosis in breast cancer, especially in ER- and PR-negative tumors. Further investigations are warranted to fully comprehend the role of SEMA3A in breast cancer biology, which may lead to the identification of novel therapeutic targets and personalized treatment strategies for breast cancer patients.


Assuntos
Semaforina-3A , Neoplasias de Mama Triplo Negativas , Humanos , Antígeno Ki-67 , Estrogênios , Progesterona
11.
eNeuro ; 11(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38262737

RESUMO

Spinal cord injury (SCI) often results in various long-term sequelae, and chronically injured spinal cords exhibit a refractory feature, showing a limited response to cell transplantation therapies. To our knowledge, no preclinical studies have reported a treatment approach with results surpassing those of treatment comprising rehabilitation alone. In this study of rats with SCI, we propose a novel combined therapy involving a semaphorin 3A inhibitor (Sema3Ai), which enhances axonal regeneration, as the third treatment element in combination with neural stem/progenitor cell transplantation and rehabilitation. This comprehensive therapeutic strategy achieved significant improvements in host-derived neuronal and oligodendrocyte differentiation at the SCI epicenter and promoted axonal regeneration even in the chronically injured spinal cord. The elongated axons established functional electrical connections, contributing to significant enhancements in locomotor mobility when compared with animals treated with transplantation and rehabilitation. As a result, our combined transplantation, Sema3Ai, and rehabilitation treatment have the potential to serve as a critical step forward for chronic SCI patients, improving their ability to regain motor function.


Assuntos
Células-Tronco Neurais , Traumatismos da Medula Espinal , Humanos , Ratos , Animais , Semaforina-3A , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco/métodos , Neurônios , Células-Tronco Neurais/transplante , Axônios , Medula Espinal , Regeneração Nervosa/fisiologia , Recuperação de Função Fisiológica/fisiologia
12.
Pathol Res Pract ; 254: 155148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277753

RESUMO

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary gland tumors. ACC is composed of myoepithelial and epithelial neoplastic cells which grow slowly and have a tendency for neural invasion. The long term prognosis is still relatively poor. Although several gene abnormalities, such as fusions involving MYB or MYBL1 oncogenes and the transcription factor gene NFIB, and overexpression of KIT have been reported in ACC, their precise functions in the pathogenesis of ACC remain unclear. We recently demonstrated that the elevated expression of Semaphorin 3A (SEMA3A), specifically expressed in myoepithelial neoplastic cells, might function as a novel oncogene-related molecule to enhance cell proliferation through activated AKT signaling in 9/10 (90%) ACC cases. In the current study, the patient with ACC whose tumor was negative for SEMA3A in the previous study, revisited our hospital with late metastasis of ACC to the cervical lymph node eight years after surgical resection of the primary tumor. We characterized this recurrent ACC, and compared it with the primary ACC using immunohistochemical methods. In the recurrent ACC, the duct lining epithelial cells, not myoepithelial neoplastic cells, showed an elevated Ki-67 index and increased cell membrane expression of C-kit, along with the expression of phosphorylated ERK. Late metastasis ACC specimens were not positive for ß-catenin and lymphocyte enhancer binding factor 1 (LEF1), which were detected in the nuclei of perineural infiltrating cells in primary ACC cells. In addition, experiments with the GSK-3 inhibitor revealed that ß-catenin pathway suppressed not only KIT expression but also proliferation of ACC cells. Moreover, stem cell factor (SCF; also known as KIT ligand, KITL) induced ERK activation in ACC cells. These results suggest that inactivation of Wnt/ß-catenin signaling may promote C-kit-ERK signaling and cell proliferation of in metastatic ACC.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Adenoide Cístico/patologia , beta Catenina/metabolismo , Cateninas/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Semaforina-3A , Recidiva Local de Neoplasia , Neoplasias das Glândulas Salivares/patologia , Via de Sinalização Wnt , Proteínas Proto-Oncogênicas c-kit/metabolismo
13.
Int J Oral Sci ; 16(1): 5, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38238300

RESUMO

Bone formation and deposition are initiated by sensory nerve infiltration in adaptive bone remodeling. Here, we focused on the role of Semaphorin 3A (Sema3A), expressed by sensory nerves, in mechanical loads-induced bone formation and nerve withdrawal using orthodontic tooth movement (OTM) model. Firstly, bone formation was activated after the 3rd day of OTM, coinciding with a decrease in sensory nerves and an increase in pain threshold. Sema3A, rather than nerve growth factor (NGF), highly expressed in both trigeminal ganglion and the axons of periodontal ligament following the 3rd day of OTM. Moreover, in vitro mechanical loads upregulated Sema3A in neurons instead of in human periodontal ligament cells (hPDLCs) within 24 hours. Furthermore, exogenous Sema3A restored the suppressed alveolar bone formation and the osteogenic differentiation of hPDLCs induced by mechanical overload. Mechanistically, Sema3A prevented overstretching of F-actin induced by mechanical overload through ROCK2 pathway, maintaining mitochondrial dynamics as mitochondrial fusion. Therefore, Sema3A exhibits dual therapeutic effects in mechanical loads-induced bone formation, both as a pain-sensitive analgesic and a positive regulator for bone formation.


Assuntos
Osteogênese , Semaforina-3A , Humanos , Remodelação Óssea , Diferenciação Celular , Semaforina-3A/metabolismo , Semaforina-3A/farmacologia , Gânglio Trigeminal/metabolismo
14.
J Hypertens ; 42(5): 816-827, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38165021

RESUMO

Thoracic aortic aneurysm and dissection (TAAD) is a life-threatening disease and currently there is no pharmacological therapy. Sympathetic nerve overactivity plays an important role in the development of TAAD. Sympathetic innervation is mainly controlled by nerve growth factor (NGF, a key neural chemoattractant) and semaphoring 3A (Sema3A, a key neural chemorepellent), while the roles of these two factors in aortic sympathetic innervation and especially TAAD are unknown. We hypothesized that genetically manipulating the NGF/Sema3A ratio by the Ngf -driven Sema3a expression approach may reduce aortic sympathetic nerve innervation and mitigate TAAD progression. A mouse strain of Ngf gene-driven Sema3a expression (namely NgfSema3a/Sema3a mouse) was established by inserting the 2A-Sema3A expression frame to the Ngf terminating codon using CRISPR/Cas9 technology. TAAD was induced by ß-aminopropionitrile monofumarate (BAPN) both in NgfSema3a/Sema3a mice and wild type (WT) littermates. Contrary to our expectation, the BAPN-induced TAAD was severer in NgfSema3a/Sema3a mice than in wild-type (WT) mice. In addition, NgfSema3a/Sema3a mice showed higher aortic sympathetic innervation, inflammation and extracellular matrix degradation than the WT mice after BAPN treatment. The aortic vascular smooth muscle cells isolated from NgfSema3a/Sema3a mice and pretreated with BAPN in vivo for two weeks showed stronger capabilities of proliferation and migration than that from the WT mice. We conclude that the strategy of Ngf -driven Sema3a expression cannot suppress but worsens the BAPN-induced TAAD. By investigating the aortic phenotype of NgfSema3a/Sema3a mouse strain, we unexpectedly find a path to exacerbate BAPN-induced TAAD which might be useful in future TAAD studies.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Azidas , Desoxiglucose , Animais , Camundongos , Aminopropionitrilo/efeitos adversos , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/induzido quimicamente , Aneurisma da Aorta Torácica/metabolismo , Desoxiglucose/análogos & derivados , Modelos Animais de Doenças , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/efeitos adversos , Semaforina-3A/genética
15.
Sci Signal ; 17(819): eadh7673, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227686

RESUMO

The precise development of neuronal morphologies is crucial to the establishment of synaptic circuits and, ultimately, proper brain function. Signaling by the axon guidance cue semaphorin 3A (Sema3A) and its receptor complex of neuropilin-1 and plexin-A4 has multifunctional outcomes in neuronal morphogenesis. Downstream activation of the RhoGEF FARP2 through interaction with the lysine-arginine-lysine motif of plexin-A4 and consequent activation of the small GTPase Rac1 promotes dendrite arborization, but this pathway is dispensable for axon repulsion. Here, we investigated the interplay of small GTPase signaling mechanisms underlying Sema3A-mediated dendritic elaboration in mouse layer V cortical neurons in vitro and in vivo. Sema3A promoted the binding of the small GTPase Rnd1 to the amino acid motif lysine-valine-serine (LVS) in the cytoplasmic domain of plexin-A4. Rnd1 inhibited the activity of the small GTPase RhoA and the kinase ROCK, thus supporting the activity of the GTPase Rac1, which permitted the growth and branching of dendrites. Overexpression of a dominant-negative RhoA, a constitutively active Rac1, or the pharmacological inhibition of ROCK activity rescued defects in dendritic elaboration in neurons expressing a plexin-A4 mutant lacking the LVS motif. Our findings provide insights into the previously unappreciated balancing act between Rho and Rac signaling downstream of specific motifs in plexin-A4 to mediate Sema3A-dependent dendritic elaboration in mammalian cortical neuron development.


Assuntos
Moléculas de Adesão Celular , Proteínas Monoméricas de Ligação ao GTP , Proteínas do Tecido Nervoso , Semaforinas , Camundongos , Animais , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Semaforina-3A/genética , Semaforina-3A/metabolismo , Lisina/metabolismo , Neurônios/metabolismo , Dendritos/metabolismo , Semaforinas/metabolismo , Mamíferos/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
16.
Neuroscience ; 536: 36-46, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-37967738

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE) is an abnormal neurological condition caused by hypoxic-ischemic damage during the perinatal period. Human placenta derived mesenchymal stem cells (hPMSCs) have been shown to have protective and reparative effects in various neurological diseases; however, the research on HIE is insufficient. This study aimed to establish a rat model of HIE and transplant hPMSCs through the lateral ventricle after hypoxic-ishcemic (HI) brain damage to observe its protective effects and mechanisms, with a focus on brain apoptosis compared among groups. Differentially expressed apoptosis-related proteins were screened using a rat cytokine array and subsequent verification. Neuropilin-1 (NRP-1) and Semaphorin 3A (Sema 3A) were selected for further investigation. Western blotting was used to quantify the expression of Sema 3A and the proteins related to PI3K/Akt/mTOR signaling pathway. Exogenous Sema 3A was added to evaluate the effects of Sema 3A/NRP-1 on hPMSCs following HI injury. hPMSCs transplantation ameliorated HI-induced pathological changes, reduced apoptosis, and improved long-term neurological prognosis. Furthermore, Sema 3A/NRP-1 was a key regulator in reducing HI-induced apoptosis after hPMSCs transplantation. hPMSCs inhibited the expression of Sema 3A/NRP-1 and activated the PI3K/Akt/mTOR signaling pathway. Additionally, exogenous Sema 3A abolished the protective effects of hPMSCs against HI. In conclusion, hPMSCs transplantation reduced apoptosis and improved long-term neurological prognosis after HI by downregulating Sema 3A/NRP-1 expression and activating the PI3K/Akt/mTOR signaling pathway.


Assuntos
Células-Tronco Mesenquimais , Semaforina-3A , Feminino , Gravidez , Ratos , Humanos , Animais , Animais Recém-Nascidos , Neuropilina-1 , Proteínas Proto-Oncogênicas c-akt , Fosfatidilinositol 3-Quinases , Serina-Treonina Quinases TOR , Apoptose , Células-Tronco Mesenquimais/metabolismo
18.
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
19.
Cell Mol Biol (Noisy-le-grand) ; 69(10): 9-16, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37953590

RESUMO

Soluble epoxide hydrolase (sEH) inhibition has currently emerged as a therapeutic target in the treatment of various neuroinflammatory neurodegenerative diseases, including multiple sclerosis. Previously, we reported that treatment of mice with a sEH-selective inhibitor, 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl]urea; TPPU), ameliorated chronic experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein 35-55 peptide immunization followed by injection of pertussis toxin to mice via regulating pro-inflammatory and anti-inflammatory pathways in the central nervous system. This study tested the hypothesis that the pro-inflammatory G protein-coupled receptor (GPR) 75 and anti-apoptotic phospholipase C (PLC) signaling pathways also contribute to the ameliorating effect of TPPU on chronic EAE. Brains and spinal cords of phosphate-buffered saline-, dimethyl sulfoxide-, or TPPU (3 mg/kg)-treated mice were used for the measurement of sEH, GPR75, Gaq/11, activator protein (AP)-1, PLC ß4, phosphoinositide 3-kinase (PI3K) p85a, Akt1, mitogen-activated protein kinase kinase (MEK) 1/2, extracellular signal-regulated kinase (ERK) 1/2, cyclic adenosine monophosphate-response element-binding protein (CREB) 1, B-cell lymphoma (Bcl)-2, semaphorin (SEMA) 3A, and myelin proteolipid protein (PLP) expression and/or activity by using the immunoblotting method. Expression of sEH, GPR75, Gaq/11, c-jun, phosphorylated c-Jun, and SEMA3A was lower, while PLCß4, phosphorylated PI3K p85a, phosphorylated Akt1, phosphorylated MEK1/2, phosphorylated ERK1/2, phosphorylated CREB1, Bcl-2, and myelin PLP expression was higher in the tissues of TPPU (3 mg/kg)-treated mice as compared with the EAE and vehicle control groups. Inhibition of sEH by TPPU ameliorates chronic EAE through suppressing pro-inflammatory GPR75/Gaq/11/AP-1 pathway and reducing expression of the remyelination inhibitor, SEMA3A, as well as increasing anti-apoptotic PLC/PI3K/Akt1/MEK1/2/ERK1/2/CREB1/Bcl-2 pathway activity and myelin PLP expression.


Assuntos
Encefalomielite Autoimune Experimental , Fosfolipases , Receptores Acoplados a Proteínas G , Transdução de Sinais , Animais , Camundongos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Epóxido Hidrolases/antagonistas & inibidores , Epóxido Hidrolases/metabolismo , Camundongos Endogâmicos C57BL , Proteína Proteolipídica de Mielina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Semaforina-3A , Receptores Acoplados a Proteínas G/metabolismo
20.
Indian J Med Res ; 158(4): 432-438, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38006346

RESUMO

BACKGROUND OBJECTIVES: Semaphorins were initially characterized as axon guidance factors but were subsequently implicated in the regulation of immune responses, angiogenesis, organ formation and a variety of other physiological and developmental functions. Various semaphorins enhance or inhibit tumour progression through different mechanisms. The objective of this study was to assess the expression of various semaphorins and vascular endothelial growth factor (VEGF) gene transcripts as well as the serum level of Sema3A in individuals with laryngeal squamous cell carcinoma (LSCC). METHODS: Tissue expression of Sema3A, Sema3C, Sema4D, Sema6D and VEGF was determined in both tumour tissues and tissues around the tumour from 30 individuals with pathologically confirmed LSCC using quantitative real-time PCR. Furthermore, the serum level of Sema3A in these individuals was assessed using enzyme-linked immunosorbent assay. RESULTS: Sema3C gene transcript showed a significant increase (P=0.001), while Sema4D was observed with a significant decrease in tumour samples compared to non-tumoural tissues (P≤0.01). The expression of the Sema3C gene was found to be associated with the stage of LSCC tumour as it was statistically significant for tumours with stage IV (P<0.01). The serum level of Sema3A was not found to be significant between cases and controls. INTERPRETATION CONCLUSIONS: Increased expression of Sema3C but decreased expression of Sema4D in tumour tissue of LSCC may introduce these two growth factors as crucial mediators orchestrating tumour growth in individuals with LSCC. This result could open a new vision for the treatment of this malignancy.


Assuntos
Neoplasias de Cabeça e Pescoço , Semaforinas , Humanos , Semaforina-3A/genética , Semaforina-3A/metabolismo , Fator A de Crescimento do Endotélio Vascular , Carcinoma de Células Escamosas de Cabeça e Pescoço , Semaforinas/genética , Semaforinas/metabolismo
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