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1.
Signal Transduct Target Ther ; 9(1): 169, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956074

RESUMO

More than 90% of hepatocellular carcinoma (HCC) cases develop in the presence of fibrosis or cirrhosis, making the tumor microenvironment (TME) of HCC distinctive due to the intricate interplay between cancer-associated fibroblasts (CAFs) and cancer stem cells (CSCs), which collectively regulate HCC progression. However, the mechanisms through which CSCs orchestrate the dynamics of the tumor stroma during HCC development remain elusive. Our study unveils a significant upregulation of Sema3C in fibrotic liver, HCC tissues, peripheral blood of HCC patients, as well as sorafenib-resistant tissues and cells, with its overexpression correlating with the acquisition of stemness properties in HCC. We further identify NRP1 and ITGB1 as pivotal functional receptors of Sema3C, activating downstream AKT/Gli1/c-Myc signaling pathways to bolster HCC self-renewal and tumor initiation. Additionally, HCC cells-derived Sema3C facilitated extracellular matrix (ECM) contraction and collagen deposition in vivo, while also promoting the proliferation and activation of hepatic stellate cells (HSCs). Mechanistically, Sema3C interacted with NRP1 and ITGB1 in HSCs, activating downstream NF-kB signaling, thereby stimulating the release of IL-6 and upregulating HMGCR expression, consequently enhancing cholesterol synthesis in HSCs. Furthermore, CAF-secreted TGF-ß1 activates AP1 signaling to augment Sema3C expression in HCC cells, establishing a positive feedback loop that accelerates HCC progression. Notably, blockade of Sema3C effectively inhibits tumor growth and sensitizes HCC cells to sorafenib in vivo. In sum, our findings spotlight Sema3C as a novel biomarker facilitating the crosstalk between CSCs and stroma during hepatocarcinogenesis, thereby offering a promising avenue for enhancing treatment efficacy and overcoming drug resistance in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Semaforinas , Microambiente Tumoral , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Microambiente Tumoral/genética , Semaforinas/genética , Semaforinas/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Camundongos , Transdução de Sinais/genética , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Neuropilina-1/genética , Neuropilina-1/metabolismo , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica/genética , Sorafenibe/farmacologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Progressão da Doença
2.
Invest Ophthalmol Vis Sci ; 65(6): 34, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38913005

RESUMO

Purpose: The aim of this study was to elucidate the role of Sema4D in the pathogenesis of senescence-associated choroidal neovascularization (CNV) and to explore its underlying mechanisms. Methods: In this study, we utilized a model of laser-induced CNV in both young (3 months old) and old (18 months old) mice, including those with or without Sema4D knockout. The expression and localization of Sema4D in CNV were assessed using PCR, Western blot, and immunostaining. Subsequently, the morphological and imaging examinations were used to evaluate the size of CNV and vascular leakage. Finally, the expression of M2 markers, senescence-related markers, and molecules involved in the RhoA/ROCK pathway was detected. Results: We found that Sema4D was predominantly expressed in macrophages within CNV lesions, and both the mRNA and protein levels of Sema4D progressively increased following laser photocoagulation, a trend more pronounced in old mice. Moreover, Sema4D knockout markedly inhibited M2 polarization in senescent macrophages and reduced the size and leakage of CNV, particularly in aged mice. Mechanistically, aging was found to upregulate RhoA/ROCK signaling, and knockout of Sema4D effectively suppressed the activation of this pathway, with more significant effects observed in aged mice. Conclusions: Our findings revealed that the deletion of Sema4D markedly inhibited M2 macrophage polarization through the suppression of the RhoA/ROCK pathway, ultimately leading to the attenuation of senescence-associated CNV. These data indicate that targeting Sema4D could offer a promising approach for gene editing therapy in patients with neovascular age-related macular degeneration.


Assuntos
Neovascularização de Coroide , Modelos Animais de Doenças , Macrófagos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Semaforinas , Transdução de Sinais , Quinases Associadas a rho , Proteína rhoA de Ligação ao GTP , Animais , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/genética , Neovascularização de Coroide/patologia , Camundongos , Macrófagos/metabolismo , Quinases Associadas a rho/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Transdução de Sinais/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Antígenos CD/metabolismo , Antígenos CD/genética , Western Blotting , Masculino , Angiofluoresceinografia
3.
Dev Growth Differ ; 66(5): 308-319, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761018

RESUMO

One of the major functions of the semaphorin signaling system is the regulation of cell shape. In the nematode Caenorhabditis elegans, membrane-bound semaphorins SMP-1/2 (SMPs) regulate the morphology of epidermal cells via their receptor plexin, PLX-1. In the larval male tail of the SMP-PLX-1 signaling mutants, the border between two epidermal cells, R1.p and R2.p, is displaced anteriorly, resulting in the anterior displacement of the anterior-most ray, ray 1, in the adult male. To elucidate how the intercellular signaling mediated by SMPs regulates the position of the intercellular border, we performed mosaic gene expression analyses by using infrared laser-evoked gene operator (IR-LEGO). We show that PLX-1 expressed in R1.p and SMP-1 expressed in R2.p are required for the proper positioning of ray 1. The result suggests that SMP signaling promotes extension, rather than retraction, of R1.p. This is in contrast to a previous finding that SMPs mediate inhibition of cell extension of vulval precursor cells, another group of epidermal cells of C. elegans, indicating the context dependence of cell shape control via the semaphorin signaling system.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Epiderme , Semaforinas , Animais , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Semaforinas/metabolismo , Semaforinas/genética , Epiderme/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Transdução de Sinais , Comunicação Celular , Células Epidérmicas/metabolismo , Células Epidérmicas/citologia , Masculino
4.
Development ; 151(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38738602

RESUMO

Visual circuit development is characterized by subdivision of neuropils into layers that house distinct sets of synaptic connections. We find that, in the Drosophila medulla, this layered organization depends on the axon guidance regulator Plexin A. In Plexin A null mutants, synaptic layers of the medulla neuropil and arborizations of individual neurons are wider and less distinct than in controls. Analysis of semaphorin function indicates that Semaphorin 1a, acting in a subset of medulla neurons, is the primary partner for Plexin A in medulla lamination. Removal of the cytoplasmic domain of endogenous Plexin A has little effect on the formation of medulla layers; however, both null and cytoplasmic domain deletion mutations of Plexin A result in an altered overall shape of the medulla neuropil. These data suggest that Plexin A acts as a receptor to mediate morphogenesis of the medulla neuropil, and as a ligand for Semaphorin 1a to subdivide it into layers. Its two independent functions illustrate how a few guidance molecules can organize complex brain structures by each playing multiple roles.


Assuntos
Proteínas de Drosophila , Morfogênese , Proteínas do Tecido Nervoso , Neurópilo , Lobo Óptico de Animais não Mamíferos , Receptores de Superfície Celular , Semaforinas , Animais , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Semaforinas/metabolismo , Semaforinas/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Morfogênese/genética , Neurópilo/metabolismo , Lobo Óptico de Animais não Mamíferos/metabolismo , Lobo Óptico de Animais não Mamíferos/embriologia , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/genética , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/embriologia , Neurônios/metabolismo , Drosophila/metabolismo , Drosophila/embriologia , Mutação/genética
5.
Vascul Pharmacol ; 155: 107381, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795838

RESUMO

AIMS: Bone morphogenetic protein-9 (BMP9) is critical for bone morphogenetic protein receptor type-2 (BMPR2) signalling in pulmonary vascular endothelial cells. Furthermore, human genetics studies support the central role of disrupted BMPR2 mediated BMP9 signalling in vascular endothelial cells in the initiation of pulmonary arterial hypertension (PAH). In addition, loss-of-function mutations in BMP9 have been identified in PAH patients. BMP9 is considered to play an important role in vascular homeostasis and quiescence. METHODS AND RESULTS: We identified a novel BMP9 target as the class-3 semaphorin, SEMA3G. Although originally identified as playing a role in neuronal development, class-3 semaphorins may have important roles in endothelial function. Here we show that BMP9 transcriptional regulation of SEMA3G occurs via ALK1 and the canonical Smad pathway, requiring both Smad1 and Smad5. Knockdown studies demonstrated redundancy between type-2 receptors in that BMPR2 and ACTR2A were compensatory. Increased SEMA3G expression by BMP9 was found to be regulated by the transcription factor, SOX17. Moreover, we observed that SEMA3G regulates VEGF signalling by inhibiting VEGFR2 phosphorylation and that VEGF, in contrast to BMP9, negatively regulated SEMA3G transcription. Functional endothelial cell assays of VEGF-mediated migration and network formation revealed that BMP9 inhibition of VEGF was abrogated by SEMA3G knockdown. Conversely, treatment with recombinant SEMA3G partially mimicked the inhibitory action of BMP9 in these assays. CONCLUSIONS: This study provides further evidence for the anti-angiogenic role of BMP9 in microvascular endothelial cells and these functions are mediated at least in part via SOX17 and SEMA3G induction.


Assuntos
Movimento Celular , Células Endoteliais , Fator 2 de Diferenciação de Crescimento , Semaforinas , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular , Humanos , Movimento Celular/efeitos dos fármacos , Semaforinas/metabolismo , Semaforinas/genética , Fator 2 de Diferenciação de Crescimento/genética , Fator 2 de Diferenciação de Crescimento/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Proteína Smad5/metabolismo , Proteína Smad5/genética , Receptores de Ativinas Tipo I/metabolismo , Receptores de Ativinas Tipo I/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Proteína Smad1/metabolismo , Proteína Smad1/genética , Pulmão/metabolismo , Pulmão/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Células Cultivadas
6.
Cell Rep Med ; 5(5): 101554, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38729157

RESUMO

The axons of retinal ganglion cells (RGCs) form the optic nerve, transmitting visual information from the eye to the brain. Damage or loss of RGCs and their axons is the leading cause of visual functional defects in traumatic injury and degenerative diseases such as glaucoma. However, there are no effective clinical treatments for nerve damage in these neurodegenerative diseases. Here, we report that LIM homeodomain transcription factor Lhx2 promotes RGC survival and axon regeneration in multiple animal models mimicking glaucoma disease. Furthermore, following N-methyl-D-aspartate (NMDA)-induced excitotoxicity damage of RGCs, Lhx2 mitigates the loss of visual signal transduction. Mechanistic analysis revealed that overexpression of Lhx2 supports axon regeneration by systematically regulating the transcription of regeneration-related genes and inhibiting transcription of Semaphorin 3C (Sema3C). Collectively, our studies identify a critical role of Lhx2 in promoting RGC survival and axon regeneration, providing a promising neural repair strategy for glaucomatous neurodegeneration.


Assuntos
Axônios , Modelos Animais de Doenças , Glaucoma , Proteínas com Homeodomínio LIM , Regeneração Nervosa , Células Ganglionares da Retina , Fatores de Transcrição , Animais , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Proteínas com Homeodomínio LIM/metabolismo , Proteínas com Homeodomínio LIM/genética , Glaucoma/genética , Glaucoma/patologia , Glaucoma/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Axônios/metabolismo , Axônios/patologia , Camundongos , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Camundongos Endogâmicos C57BL , Sobrevivência Celular/genética , Semaforinas/metabolismo , Semaforinas/genética , N-Metilaspartato/metabolismo
7.
Commun Biol ; 7(1): 541, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714838

RESUMO

Age-related diseases pose great challenges to health care systems worldwide. During aging, endothelial senescence increases the risk for cardiovascular disease. Recently, it was described that Phosphatase 1 Nuclear Targeting Subunit (PNUTS) has a central role in cardiomyocyte aging and homeostasis. Here, we determine the role of PNUTS in endothelial cell aging. We confirm that PNUTS is repressed in senescent endothelial cells (ECs). Moreover, PNUTS silencing elicits several of the hallmarks of endothelial aging: senescence, reduced angiogenesis and loss of barrier function. Findings are validate in vivo using endothelial-specific inducible PNUTS-deficient mice (Cdh5-CreERT2;PNUTSfl/fl), termed PNUTSEC-KO. Two weeks after PNUTS deletion, PNUTSEC-KO mice present severe multiorgan failure and vascular leakage. Transcriptomic analysis of PNUTS-silenced HUVECs and lungs of PNUTSEC-KO mice reveal that the PNUTS-PP1 axis tightly regulates the expression of semaphorin 3B (SEMA3B). Indeed, silencing of SEMA3B completely restores barrier function after PNUTS loss-of-function. These results reveal a pivotal role for PNUTS in endothelial homeostasis through a SEMA3B downstream pathway that provides a potential target against the effects of aging in ECs.


Assuntos
Senescência Celular , Células Endoteliais da Veia Umbilical Humana , Semaforinas , Animais , Humanos , Camundongos , Envelhecimento/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Semaforinas/metabolismo , Semaforinas/genética
8.
Proc Natl Acad Sci U S A ; 121(22): e2400648121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38781210

RESUMO

After central nervous system injury, a rapid cellular and molecular response is induced. This response can be both beneficial and detrimental to neuronal survival in the first few days and increases the risk for neurodegeneration if persistent. Semaphorin4B (Sema4B), a transmembrane protein primarily expressed by cortical astrocytes, has been shown to play a role in neuronal cell death following injury. Our study shows that after cortical stab wound injury, cytokine expression is attenuated in Sema4B-/- mice, and microglia/macrophage reactivity is altered. In vitro, Sema4B enhances the reactivity of microglia following injury, suggesting astrocytic Sema4B functions as a ligand. Moreover, injury-induced microglia reactivity is attenuated in the presence of Sema4B-/- astrocytes compared to Sema4B+/- astrocytes. In vitro experiments indicate that Plexin-B2 is the Sema4B receptor on microglia. Consistent with this, in microglia/macrophage-specific Plexin-B2-/- mice, similar to Sema4B-/- mice, microglial/macrophage reactivity and neuronal cell death are attenuated after cortical injury. Finally, in Sema4B/Plexin-B2 double heterozygous mice, microglial/macrophage reactivity is also reduced after injury, supporting the idea that both Sema4B and Plexin-B2 are part of the same signaling pathway. Taken together, we propose a model in which following injury, astrocytic Sema4B enhances the response of microglia/macrophages via Plexin-B2, leading to increased reactivity.


Assuntos
Astrócitos , Camundongos Knockout , Microglia , Proteínas do Tecido Nervoso , Semaforinas , Animais , Camundongos , Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/genética , Comunicação Celular , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Semaforinas/metabolismo , Semaforinas/genética
9.
Nat Commun ; 15(1): 4564, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811591

RESUMO

Accurate non-invasive biomarkers to diagnose metabolic dysfunction-associated steatotic liver disease (MASLD)-related fibrosis are urgently needed. This study applies a translational approach to develop a blood-based biomarker panel for fibrosis detection in MASLD. A molecular gene expression signature identified from a diet-induced MASLD mouse model (LDLr-/-.Leiden) is translated into human blood-based biomarkers based on liver biopsy transcriptomic profiles and protein levels in MASLD patient serum samples. The resulting biomarker panel consists of IGFBP7, SSc5D and Sema4D. LightGBM modeling using this panel demonstrates high accuracy in predicting MASLD fibrosis stage (F0/F1: AUC = 0.82; F2: AUC = 0.89; F3/F4: AUC = 0.87), which is replicated in an independent validation cohort. The overall accuracy of the model outperforms predictions by the existing markers Fib-4, APRI and FibroScan. In conclusion, here we show a disease mechanism-related blood-based biomarker panel with three biomarkers which is able to identify MASLD patients with mild or advanced hepatic fibrosis with high accuracy.


Assuntos
Biomarcadores , Cirrose Hepática , Semaforinas , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Biomarcadores/sangue , Animais , Masculino , Camundongos , Feminino , Semaforinas/sangue , Semaforinas/genética , Semaforinas/metabolismo , Pessoa de Meia-Idade , Fígado Gorduroso/sangue , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/patologia , Fígado/patologia , Fígado/metabolismo , Modelos Animais de Doenças , Receptores de LDL/genética , Receptores de LDL/metabolismo , Transcriptoma , Camundongos Knockout , Adulto , Camundongos Endogâmicos C57BL , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina
10.
Scand J Immunol ; 99(5): e13360, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38605547

RESUMO

Myasthenia gravis (MG) is an autoantibody-mediated disease of the neuromuscular junction. Semaphorin 4A (Sema4A) is involved in the activation of T cells in various inflammatory disorders. In this study, we aimed to investigate whether Sema4A is involved in the pathogenesis of MG. We measured serum Sema4A concentrations in 30 treatment-naïve MG patients with acetylcholine receptor (AChR) antibodies, 7 with muscle-specific tyrosine kinase (MuSK) antibodies and 21 normal controls. As a result, serum Sema4A levels were significantly higher in patients with AChR antibody-positive MG and MuSK antibody-positive MG than in controls (p ≤ 0.0001 for both MG groups). Serum Sema4A levels were correlated with AChR antibody levels (Spearman's ρ = 0.39, p = 0.03) and MG Foundation of America clinical classification classes (Spearman's ρ = 0.38, p = 0.04) in patients with AChR antibody-positive MG. In conclusion, high serum Sema4A levels may reflect T-cell activation, and this molecule could be a potential marker of disease activity in MG.


Assuntos
Miastenia Gravis , Semaforinas , Humanos , Miastenia Gravis/diagnóstico , Autoanticorpos
11.
Cells ; 13(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38607057

RESUMO

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases. Inflammation of the synovial fluid propagates the pathological process of angiogenesis. Semaphorins play a crucial role in the context of endothelial cell function, and their pleiotropic nature has various effects on the further development of RA. This narrative review summarises the various roles of semaphorins in the pathology of RA and whether they could play a role in developing novel RA treatment options.


Assuntos
Artrite Reumatoide , Doenças Autoimunes , Semaforinas , Humanos , Inflamação , Líquido Sinovial
12.
Int Immunopharmacol ; 132: 112035, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38603857

RESUMO

Hallmark features of the tumor microenvironment include immune cells, stromal cells, blood vessels, and extracellular matrix (ECM), providing a conducive environment for the growth and survival of tumors. Recent advances in the understanding of cancer biology have highlighted the functional role of semaphorins (SEMAs). SEMAs are a large and diverse family of widely expressed secreted and membrane-binding proteins, which were initially implicated in axon guidance and neural development. However, it is now clear that they are widely expressed beyond the nervous system and participate in regulating immune responses and cancer progression. In fact, accumulating evidence disclosed that different SEMAs can either stimulate or restrict tumor progression, some of which act as important regulators of tumor angiogenesis. Conversely, limited information is known about the functional relevance of SEMA signals in TME. In this setting, we systematically elaborate the role SEMAs and their major receptors played in characterized components of TME. Furthermore, we provide a convergent view of current SEMAs pharmacological progress in clinical treatment and also put forward their potential application value and clinical prospects in the future.


Assuntos
Neoplasias , Semaforinas , Microambiente Tumoral , Animais , Humanos , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/terapia , Neovascularização Patológica/imunologia , Semaforinas/metabolismo , Transdução de Sinais
13.
BMC Pediatr ; 24(1): 285, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678170

RESUMO

BACKGROUND: Kawasaki disease (KD) is a pediatric systemic vasculitis characterized by endothelial cell dysfunction. Semaphorin 7A (Sema7A) has been reported to regulate endothelial phenotypes associated with cardiovascular diseases, while its role in KD remains unknown. This study aims to investigate the effect of Sema7A on endothelial permeability and inflammatory response in KD conditions. METHODS: Blood samples were collected from 68 KD patients and 25 healthy children (HC). The levels of Sema7A and A Disintegrin and Metalloprotease 17 (ADAM17) in serum were measured by enzyme-linked immunosorbent assay (ELISA), and Sema7A expression in blood cells was analyzed by flow cytometry. Ex vivo monocytes were used for Sema7A shedding assays. In vitro human coronary artery endothelial cells (HCAECs) were cultured in KD sera and stimulated with Sema7A, and TNF-α, IL-1ß, IL-6, and IL-18 of HCAECs were measured by ELISA and qRT-PCR. HCAECs monolayer permeability was measured by FITC-dextran. RESULTS: The serum level of Sema7A was significantly higher in KD patients than in HC and correlated with disease severity. Monocytes were identified as one of the source of elevated serum Sema7A, which implicates a process of ADAM17-dependent shedding. Sera from KD patients induced upregulation of plexin C1 and integrin ß1 in HCAECs compared to sera from HC. Sema7A mediated the proinflammatory cytokine production of HCAECs in an integrin ß1-dependent manner, while both plexin C1 and integrin ß1 contributed to Sema7A-induced HCAEC hyperpermeability. CONCLUSIONS: Sema7A is involved in the progression of KD vasculitis by promoting endothelial permeability and inflammation through a plexin C1 and integrin ß1-dependent pathway. Sema7A may serve as a potential biomarker and therapeutic target in the prognosis and treatment of KD.


Assuntos
Antígenos CD , Integrina beta1 , Síndrome de Linfonodos Mucocutâneos , Receptores de Superfície Celular , Semaforinas , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Proteína ADAM17/metabolismo , Antígenos CD/metabolismo , Permeabilidade Capilar , Estudos de Casos e Controles , Células Cultivadas , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Proteínas Ligadas por GPI , Inflamação/metabolismo , Integrina beta1/metabolismo , Monócitos/metabolismo , Síndrome de Linfonodos Mucocutâneos/metabolismo , Síndrome de Linfonodos Mucocutâneos/sangue , Proteínas do Tecido Nervoso/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/sangue , Semaforinas/metabolismo , Semaforinas/sangue
14.
Am J Physiol Cell Physiol ; 326(6): C1659-C1668, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38646784

RESUMO

Idiopathic pulmonary fibrosis (IPF) is marked by the activation of fibroblasts, leading to excessive production and deposition of extracellular matrix (ECM) within the lung parenchyma. Despite the pivotal role of ECM overexpression in IPF, potential negative regulators of ECM production in fibroblasts have yet to be identified. Semaphorin class 3B (SEMA3B), a secreted protein highly expressed in lung tissues, has established roles in axonal guidance and tumor suppression. However, the role of SEMA3B in ECM production by fibroblasts in the pathogenesis of IPF remains unexplored. Here, we show the downregulation of SEMA3B and its cognate binding receptor, neuropilin 1 (NRP1), in IPF lungs compared with healthy controls. Notably, the reduced expression of SEMA3B and NRP1 is associated with a decline in lung function in IPF. The downregulation of SEMA3B and NRP1 transcripts was validated in the lung tissues of patients with IPF, and two alternative mouse models of pulmonary fibrosis. In addition, we show that transforming growth factor-ß (TGFß) functions as a negative regulator of SEMA3B and NRP1 expression in lung fibroblasts. Furthermore, we demonstrate the antifibrotic effects of SEMA3B against TGFß-induced ECM production in IPF lung fibroblasts. Overall, our findings uncovered a novel role of SEMA3B in the pathogenesis of pulmonary fibrosis and provided novel insights into modulating the SEMA3B-NRP1 axis to attenuate pulmonary fibrosis.NEW & NOTEWORTHY The excessive production and secretion of collagens and other extracellular matrix proteins by fibroblasts lead to the scarring of the lung in severe fibrotic lung diseases. This study unveils an antifibrotic role for semaphorin class 3B (SEMA3B) in the pathogenesis of idiopathic pulmonary fibrosis. SEMA3B functions as an inhibitor of transforming growth factor-ß-driven fibroblast activation and reduced levels of SEMA3B and its receptor, neuropilin 1, are associated with decreased lung function in idiopathic pulmonary fibrosis.


Assuntos
Proteínas da Matriz Extracelular , Fibroblastos , Fibrose Pulmonar Idiopática , Pulmão , Neuropilina-1 , Semaforinas , Fator de Crescimento Transformador beta , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Células Cultivadas , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/genética , Pulmão/metabolismo , Pulmão/patologia , Glicoproteínas de Membrana , Camundongos Endogâmicos C57BL , Neuropilina-1/metabolismo , Neuropilina-1/genética , Semaforinas/metabolismo , Semaforinas/genética , Fator de Crescimento Transformador beta/metabolismo
15.
Nat Commun ; 15(1): 2723, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548715

RESUMO

Integration of extracellular signals by neurons is pivotal for brain development, plasticity, and repair. Axon guidance relies on receptor-ligand interactions crosstalking with extracellular matrix components. Semaphorin-5A (Sema5A) is a bifunctional guidance cue exerting attractive and inhibitory effects on neuronal growth through the interaction with heparan sulfate (HS) and chondroitin sulfate (CS) glycosaminoglycans (GAGs), respectively. Sema5A harbors seven thrombospondin type-1 repeats (TSR1-7) important for GAG binding, however the underlying molecular basis and functions in vivo remain enigmatic. Here we dissect the structural basis for Sema5A:GAG specificity and demonstrate the functional significance of this interaction in vivo. Using x-ray crystallography, we reveal a dimeric fold variation for TSR4 that accommodates GAG interactions. TSR4 co-crystal structures identify binding residues validated by site-directed mutagenesis. In vitro and cell-based assays uncover specific GAG epitopes necessary for TSR association. We demonstrate that HS-GAG binding is preferred over CS-GAG and mediates Sema5A oligomerization. In vivo, Sema5A:GAG interactions are necessary for Sema5A function and regulate Plexin-A2 dependent dentate progenitor cell migration. Our study rationalizes Sema5A associated developmental and neurological disorders and provides mechanistic insights into how multifaceted guidance functions of a single transmembrane cue are regulated by proteoglycans.


Assuntos
Glicosaminoglicanos , Semaforinas , Glicosaminoglicanos/metabolismo , Proteoglicanas/metabolismo , Heparitina Sulfato/metabolismo , Movimento Celular , Semaforinas/genética , Semaforinas/metabolismo
16.
Blood Adv ; 8(11): 2660-2674, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38489236

RESUMO

ABSTRACT: Pulmonary defense mechanisms are critical for host integrity during pneumonia and sepsis. This defense is fundamentally dependent on the activation of neutrophils during the innate immune response. Recent work has shown that semaphorin 7A (Sema7A) holds significant impact on platelet function, yet its role on neutrophil function within the lung is not well understood. This study aimed to identify the role of Sema7A during pulmonary inflammation and sepsis. In patients with acute respiratory distress syndrome (ARDS), we were able to show a correlation between Sema7A and oxygenation levels. During subsequent workup, we found that Sema7A binds to the neutrophil PlexinC1 receptor, increasing integrins, and L-selectin on neutrophils. Sema7A prompted neutrophil chemotaxis in vitro and the formation of platelet-neutrophil complexes in vivo. We also observed altered adhesion and transmigration of neutrophils in Sema7A-/-animals in the lung during pulmonary inflammation. This effect resulted in increased number of neutrophils in the interstitial space of Sema7A-/- animals but reduced numbers of neutrophils in the alveolar space during pulmonary sepsis. This finding was associated with significantly worse outcome of Sema7A-/- animals in a model of pulmonary sepsis. Sema7A has an immunomodulatory effect in the lung, affecting pulmonary sepsis and ARDS. This effect influences the response of neutrophils to external aggression and might influence patient outcome. This trial was registered at www.ClinicalTrials.gov as #NCT02692118.


Assuntos
Antígenos CD , Neutrófilos , Pneumonia , Semaforinas , Sepse , Semaforinas/metabolismo , Sepse/imunologia , Sepse/metabolismo , Neutrófilos/metabolismo , Neutrófilos/imunologia , Humanos , Animais , Camundongos , Antígenos CD/metabolismo , Pneumonia/metabolismo , Pneumonia/imunologia , Proteínas Ligadas por GPI/metabolismo , Masculino , Modelos Animais de Doenças , Camundongos Knockout , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/metabolismo , Feminino
17.
Int J Oral Sci ; 16(1): 26, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548747

RESUMO

SEMA7A belongs to the Semaphorin family and is involved in the oncogenesis and tumor progression. Aberrant glycosylation has been intricately linked with immune escape and tumor growth. SEMA7A is a highly glycosylated protein with five glycosylated sites. The underlying mechanisms of SEMA7A glycosylation and its contribution to immunosuppression and tumorigenesis are unclear. Here, we identify overexpression and aberrant N-glycosylation of SEMA7A in head and neck squamous cell carcinoma, and elucidate fucosyltransferase FUT8 catalyzes aberrant core fucosylation in SEMA7A at N-linked oligosaccharides (Asn 105, 157, 258, 330, and 602) via a direct protein‒protein interaction. A glycosylated statue of SEMA7A is necessary for its intra-cellular trafficking from the cytoplasm to the cytomembrane. Cytokine EGF triggers SEMA7A N-glycosylation through increasing the binding affinity of SEMA7A toward FUT8, whereas TGF-ß1 promotes abnormal glycosylation of SEMA7A via induction of epithelial-mesenchymal transition. Aberrant N-glycosylation of SEMA7A leads to the differentiation of CD8+ T cells along a trajectory toward an exhausted state, thus shaping an immunosuppressive microenvironment and being resistant immunogenic cell death. Deglycosylation of SEMA7A significantly improves the clinical outcome of EGFR-targeted and anti-PD-L1-based immunotherapy. Finally, we also define RBM4, a splice regulator, as a downstream effector of glycosylated SEMA7A and a pivotal mediator of PD-L1 alternative splicing. These findings suggest that targeting FUT8-SEMA7A axis might be a promising strategy for improving antitumor responses in head and neck squamous cell carcinoma patients.


Assuntos
Neoplasias de Cabeça e Pescoço , Semaforinas , Humanos , Glicosilação , Carcinoma de Células Escamosas de Cabeça e Pescoço , Linfócitos T CD8-Positivos/metabolismo , Fucosiltransferases/metabolismo , Microambiente Tumoral , Proteínas de Ligação a RNA/metabolismo , Antígenos CD/metabolismo , Semaforinas/metabolismo , Proteínas Ligadas por GPI/metabolismo
18.
Integr Cancer Ther ; 23: 15347354241233544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469817

RESUMO

BACKGROUND: In the era of precision medicine, individual temperature sensitivity has been highlighted. This trait has traditionally been used for cold-heat pattern identification to understand the inherent physical characteristics, which are influenced by genetic factors, of an individual. However, genome-wide association studies (GWASs) on this trait are limited. METHODS: Using genotype data from 90 patients with advanced non-small cell lung cancer (NSCLC) and epidermal growth factor receptor mutations, we performed a GWAS to assess the association between single nucleotide polymorphisms (SNPs) and temperature sensitivity, such as cold and heat scores. The score of each participant was evaluated using self-administered questionnaires on common symptoms and a 15-item symptom-based cold-heat pattern identification questionnaire. RESULTS: The GWAS was adjusted for confounding factors, including age and sex, and significant associations were identified for cold and heat scores: SNP rs145814326, located on the intron of SORCS2 at chromosome 4p16.1, had a P-value of 1.86 × 10-7; and SNP rs79297667, located upstream from SEMA4D at chromosome 9q22.2, had a P-value of 8.97 × 10-8. We also found that the genetic variant regulates the expression level of SEMA4D in the main tissues, including the lungs and white blood cells, in NSCLC. CONCLUSIONS: SEMA4D was found to be significantly associated with temperature sensitivity in patients with NSCLC, suggesting an increased expression of SEMA4D in patients with higher heat scores. The potential role of temperature sensitivity as a prognostic or predictive marker of immune response in NSCLC should be further studied.


Assuntos
Antígenos CD , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Semaforinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Estudo de Associação Genômica Ampla , Temperatura
19.
Biomed Pharmacother ; 173: 116385, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460369

RESUMO

Lilii Bulbus (Lilium lancifolium Thunberg) has a proneurogenic effect on the hippocampus. However, its effects on epilepsy and associated pathological features remain unknown. In this study, we investigated the antiseizure effects of a water extract of Lilii Bulbus (WELB) in mouse model of pentylenetetrazol (PTZ)-induced seizure. Mice were injected with PTZ once every 48 h until full kindling was achieved. WELB (100 and 500 mg/kg) was orally administered once daily before PTZ administration and during the kindling process. We found that WELB treatment protected against PTZ-induced low seizure thresholds and high seizure severity. Further, WELB-treated mice showed attenuated PTZ kindling-induced anxiety and memory impairment. Immunostaining and immunoblots showed that hyperactivation and ectopic migration of dentate granule cells (DGCs) were significantly reduced by WELB treatment in PTZ kindling-induced seizure mice. Staining for mossy fiber sprouting (MFS) using Timm staining and ZnT3 showed that WELB treatment significantly decreased PTZ kindling-induced MFS. Furthermore, the increased or decreased expression of proteins related to ectopic DGCs (Reelin and Dab-1), MFS (Netrin-1, Sema3A, and Sema3F), and their downstream effectors (ERK, AKT, and CREB) in the hippocampus of PTZ kindling mice was significantly restored by WELB treatment. Overall, our findings suggest that WELB is a potential antiseizure drug that acts by reducing ectopic DGCs and MFS and modulating epileptogenesis-related signaling in the hippocampus.


Assuntos
Excitação Neurológica , Semaforinas , Animais , Camundongos , Netrina-1 , Pentilenotetrazol , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/metabolismo
20.
Cytokine Growth Factor Rev ; 76: 22-29, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38472041

RESUMO

The bone marrow is a haven for hematopoietic and non-hematopoietic cells, creating complex micro-anatomical regions called niches. These distinct niches all participate in an intricate orchestra of cellular interactions that regulates the hematopoietic stem cell and its progenies. In this review, we provide a detailed description of the three most well-known bone marrow niches and their participation in hematopoiesis. We use pre-clinical data, including different in vitro and in vivo studies to discuss how a group of proteins called Semaphorins could potentially modulate both hematopoietic and non-hematopoietic cells, establishing links between the niches, semaphorins, and hematopoietic regulation. Thus, here we provide a deep dive into the inner functioning of the bone marrow and discuss the overarching implications that semaphorins might have on blood formation.


Assuntos
Medula Óssea , Semaforinas , Humanos , Diferenciação Celular/fisiologia , Semaforinas/metabolismo , Nicho de Células-Tronco/fisiologia , Células-Tronco Hematopoéticas , Hematopoese/fisiologia , Células da Medula Óssea
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