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1.
Biochem Biophys Res Commun ; 705: 149736, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38447392

RESUMO

BACKGROUND: Orosomucoid (ORM) has been reported as a biomarker of carotid atherosclerosis, but the role of ORM 2, a subtype of ORM, in carotid atherosclerotic plaque formation and the underlying mechanism have not been established. METHODS: Plasma was collected from patients with carotid artery stenosis (CAS) and healthy participants and assessed using mass spectrometry coupled with isobaric tags for relative and absolute quantification (iTRAQ) technology to identify differentially expressed proteins. The key proteins and related pathways were identified via western blotting, immunohistochemistry, and polymerase chain reaction of carotid artery plaque tissues and in vitro experiments involving vascular smooth muscle cells (VSMCs). RESULTS: We screened 33 differentially expressed proteins out of 535 proteins in the plasma. Seventeen proteins showed increased expressions in the CAS groups relative to the healthy groups, while 16 proteins showed decreased expressions during iTRAQ and bioinformatic analysis. The reactive oxygen species metabolic process was the most common enrichment pathway identified by Gene Ontology analysis, while ORM2, PRDX2, GPX3, HP, HBB, ANXA5, PFN1, CFL1, and S100A11 were key proteins identified by STRING and MCODE analysis. ORM2 showed increased expression in patients with CAS plaques, and ORM2 was accumulated in smooth muscle cells. Oleic acid increased the lipid accumulation and ORM2 and PRDX6 expressions in the VSMCs. The recombinant-ORM2 also increased the lipid accumulation and reactive oxygen species (ROS) in the VSMCs. The expressions of ORM2 and PRDX-6 were correlated, and MJ33 (an inhibitor of PRDX6-PLA2) decreased ROS production and lipid accumulation in VSMCs. CONCLUSION: ORM2 may be a biomarker for CAS; it induced lipid accumulation and ROS production in VSMCs during atherosclerosis plaque formation. However, the relationships between ORM2 and PRDX-6 underlying lipid accumulation-induced plaque vulnerability require further research.


Assuntos
Aterosclerose , Estenose das Carótidas , Placa Aterosclerótica , Humanos , Estenose das Carótidas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Orosomucoide/metabolismo , Músculo Liso Vascular/metabolismo , Aterosclerose/metabolismo , Placa Aterosclerótica/metabolismo , Biomarcadores/metabolismo , Artérias Carótidas/metabolismo , Miócitos de Músculo Liso/metabolismo , Lipídeos , Profilinas/metabolismo
2.
Nat Commun ; 15(1): 2497, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509062

RESUMO

Microglia play a pivotal role in neurodegenerative disease pathogenesis, but the mechanisms underlying microglia dysfunction and toxicity remain to be elucidated. To investigate the effect of neurodegenerative disease-linked genes on the intrinsic properties of microglia, we studied microglia-like cells derived from human induced pluripotent stem cells (iPSCs), termed iMGs, harboring mutations in profilin-1 (PFN1) that are causative for amyotrophic lateral sclerosis (ALS). ALS-PFN1 iMGs exhibited evidence of lipid dysmetabolism, autophagy dysregulation and deficient phagocytosis, a canonical microglia function. Mutant PFN1 also displayed enhanced binding affinity for PI3P, a critical signaling molecule involved in autophagic and endocytic processing. Our cumulative data implicate a gain-of-toxic function for mutant PFN1 within the autophagic and endo-lysosomal pathways, as administration of rapamycin rescued phagocytic dysfunction in ALS-PFN1 iMGs. These outcomes demonstrate the utility of iMGs for neurodegenerative disease research and implicate microglial vesicular degradation pathways in the pathogenesis of these disorders.


Assuntos
Esclerose Amiotrófica Lateral , Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Humanos , Esclerose Amiotrófica Lateral/metabolismo , Microglia/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Profilinas/metabolismo , Mutação
3.
J Cell Mol Med ; 28(7): e18266, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38501838

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), a very aggressive tumour, is currently the third leading cause of cancer-related deaths. Unfortunately, many patients face the issue of inoperability at the diagnostic phase leading to a quite dismal prognosis. The onset of metastatic processes has a crucial role in the elevated mortality rates linked to PDAC. Individuals with metastatic advances receive only palliative therapy and have a grim prognosis. It is essential to carefully analyse the intricacies of the metastatic process to enhance the prognosis for individuals with PDAC. Malignancy development is greatly impacted by the process of macrophage efferocytosis. Our current knowledge about the complete range of macrophage efferocytosis activities in PDAC and their intricate interactions with tumour cells is still restricted. This work aims to resolve communication gaps and pinpoint the essential transcription factor that is vital in the immunological response of macrophage populations. We analysed eight PDAC tissue samples sourced from the gene expression omnibus. We utilized several software packages such as Seurat, DoubletFinder, Harmony, Pi, GSVA, CellChat and Monocle from R software together with pySCENIC from Python, to analyse the single-cell RNA sequencing (scRNA-seq) data collected from the PDAC samples. This study involved the analysis of a comprehensive sample of 22,124 cells, which were classified into distinct cell types. These cell types encompassed endothelial and epithelial cells, PDAC cells, as well as various immune cells, including CD4+ T cells, CD8+ T cells, NK cells, B cells, plasma cells, mast cells, monocytes, DC cells and different subtypes of macrophages, namely C0 macrophage TGM2+, C1 macrophage PFN1+, C2 macrophage GAS6+ and C3 macrophage APOC3+. The differentiation between tumour cells and epithelial cells was achieved by the implementation of CopyKat analysis, resulting in the detection and categorization of 1941 PDAC cells. The amplification/deletion patterns observed in PDAC cells on many chromosomes differ significantly from those observed in epithelial cells. The study of Pseudotime Trajectories demonstrated that the C0 macrophage subtype expressing TGM2+ had the lowest level of differentiation. Additionally, the examination of gene set scores related to efferocytosis suggested that this subtype displayed higher activity during the efferocytosis process compared to other subtypes. The most active transcription factors for each macrophage subtype were identified as BACH1, NFE2, TEAD4 and ARID3A. In conclusion, the examination of human PDAC tissue samples using immunofluorescence analysis demonstrated the co-localization of CD68 and CD11b within regions exhibiting the presence of keratin (KRT) and alpha-smooth muscle actin (α-SMA). This observation implies a spatial association between macrophages, fibroblasts, and epithelial cells. There is variation in the expression of efferocytosis-associated genes between C0 macrophage TGM2+ and other macrophage cell types. This observation implies that the diversity of macrophage cells might potentially influence the metastatic advancement of PDAC. Moreover, the central transcription factor of different macrophage subtypes offers a promising opportunity for targeted immunotherapy in the treatment of PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Análise da Expressão Gênica de Célula Única , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Macrófagos/metabolismo , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Domínio TEA , Profilinas/genética
4.
Front Cell Infect Microbiol ; 14: 1351737, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500508

RESUMO

Monkeypox (now Mpox), a zoonotic disease caused by the monkeypox virus (MPXV) is an emerging threat to global health. In the time span of only six months, from May to October 2022, the number of MPXV cases breached 80,000 and many of the outbreaks occurred in locations that had never previously reported MPXV. Currently there are no FDA-approved MPXV-specific vaccines or treatments, therefore, finding drugs to combat MPXV is of utmost importance. The A42R profilin-like protein of the MPXV is involved in cell development and motility making it a critical drug target. A42R protein is highly conserved across orthopoxviruses, thus A42R inhibitors may work for other family members. This study sought to identify potential A42R inhibitors for MPXV treatment using computational approaches. The energy minimized 3D structure of the A42R profilin-like protein (PDB ID: 4QWO) underwent virtual screening using a library of 36,366 compounds from Traditional Chinese Medicine (TCM), AfroDb, and PubChem databases as well as known inhibitor tecovirimat via AutoDock Vina. A total of seven compounds comprising PubChem CID: 11371962, ZINC000000899909, ZINC000001632866, ZINC000015151344, ZINC000013378519, ZINC000000086470, and ZINC000095486204, predicted to have favorable binding were shortlisted. Molecular docking suggested that all seven proposed compounds have higher binding affinities to A42R (-7.2 to -8.3 kcal/mol) than tecovirimat (-6.7 kcal/mol). This was corroborated by MM/PBSA calculations, with tecovirimat demonstrating the highest binding free energy of -68.694 kJ/mol (lowest binding affinity) compared to the seven shortlisted compounds that ranged from -73.252 to -97.140 kJ/mol. Furthermore, the 7 compounds in complex with A42R demonstrated higher stability than the A42R-tecovirimat complex when subjected to 100 ns molecular dynamics simulations. The protein-ligand interaction maps generated using LigPlot+ suggested that residues Met1, Glu3, Trp4, Ile7, Arg127, Val128, Thr131, and Asn133 are important for binding. These seven compounds were adequately profiled to be potential antivirals via PASS predictions and structural similarity searches. All seven potential lead compounds were scored Pa > Pi for antiviral activity while ZINC000001632866 and ZINC000015151344 were predicted as poxvirus inhibitors with Pa values of 0.315 and 0.215, and Pi values of 0.052 and 0.136, respectively. Further experimental validations of the identified lead compounds are required to corroborate their predicted activity. These seven identified compounds represent solid footing for development of antivirals against MPXV and other orthopoxviruses.


Assuntos
Vírus da Varíola dos Macacos , Profilinas , Simulação de Acoplamento Molecular , Benzamidas , Antivirais/farmacologia
5.
Theranostics ; 14(4): 1561-1582, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389837

RESUMO

Rationale: The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) promotes pathological mitochondrial fission during septic acute kidney injury. The mitochondrial open reading frame of the 12S rRNA type-c (MOTS-c) is a mitochondria-derived peptide that exhibits anti-inflammatory properties during cardiovascular illnesses. We explored whether endotoxemia-induced myocardial microvascular injury involved DNA-PKcs and MOTS-c dysregulation. Methods: To induce endotoxemia in vivo, endothelial cell-specific DNA-PKcs-knockout mice were injected intraperitoneally with a single dose of lipopolysaccharide (10 mg/kg) and evaluated after 72 h. Results: Lipopolysaccharide exposure increased DNA-PKcs activity in cardiac microvascular endothelial cells, while pharmacological inhibition or endothelial cell-specific genetic ablation of DNA-PKcs reduced lipopolysaccharide-induced myocardial microvascular dysfunction. Proteomic analyses showed that endothelial DNA-PKcs ablation primarily altered mitochondrial protein expression. Verification assays confirmed that DNA-PKcs drastically repressed MOTS-c transcription by inducing mtDNA breaks via pathological mitochondrial fission. Inhibiting MOTS-c neutralized the endothelial protective effects of DNA-PKcs ablation, whereas MOTS-c supplementation enhanced endothelial barrier function and myocardial microvascular homeostasis under lipopolysaccharide stress. In molecular studies, MOTS-c downregulation disinhibited c-Jun N-terminal kinase (JNK), allowing JNK to phosphorylate profilin-S173. Inhibiting JNK or transfecting cells with a profilin phosphorylation-defective mutant improved endothelial barrier function by preventing F-actin depolymerization and lamellipodial degradation following lipopolysaccharide treatment. Conclusions: DNA-PKcs inactivation during endotoxemia could be a worthwhile therapeutic strategy to restore MOTS-c expression, prevent JNK-induced profilin phosphorylation, improve F-actin polymerization, and enhance lamellipodial integrity, ultimately ameliorating endothelial barrier function and reducing myocardial microvascular injury.


Assuntos
Endotoxemia , Traumatismos Cardíacos , Animais , Camundongos , Actinas , Domínio Catalítico , DNA , Proteína Quinase Ativada por DNA , Células Endoteliais , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases , Profilinas , Proteômica , Pseudópodes
6.
Sci Rep ; 14(1): 4479, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396092

RESUMO

The COVID-19 pandemic, triggered by severe acute respiratory syndrome coronavirus 2, has affected millions of people worldwide. Much research has been dedicated to our understanding of COVID-19 disease heterogeneity and severity, but less is known about recovery associated changes. To address this gap in knowledge, we quantified the proteome from serum samples from 29 COVID-19 convalescents and 29 age-, race-, and sex-matched healthy controls. Samples were acquired within the first months of the pandemic. Many proteins from pathways known to change during acute COVID-19 illness, such as from the complement cascade, coagulation system, inflammation and adaptive immune system, had returned to levels seen in healthy controls. In comparison, we identified 22 and 15 proteins with significantly elevated and lowered levels, respectively, amongst COVID-19 convalescents compared to healthy controls. Some of the changes were similar to those observed for the acute phase of the disease, i.e. elevated levels of proteins from hemolysis, the adaptive immune systems, and inflammation. In contrast, some alterations opposed those in the acute phase, e.g. elevated levels of CETP and APOA1 which function in lipid/cholesterol metabolism, and decreased levels of proteins from the complement cascade (e.g. C1R, C1S, and VWF), the coagulation system (e.g. THBS1 and VWF), and the regulation of the actin cytoskeleton (e.g. PFN1 and CFL1) amongst COVID-19 convalescents. We speculate that some of these shifts might originate from a transient decrease in platelet counts upon recovery from the disease. Finally, we observed race-specific changes, e.g. with respect to immunoglobulins and proteins related to cholesterol metabolism.


Assuntos
COVID-19 , Humanos , Pandemias , Fator de von Willebrand , Proteínas Sanguíneas , Inflamação , Colesterol , Profilinas
7.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338682

RESUMO

Pseudoexfoliation syndrome (PEX) is characterized by the accumulation of abnormal extracellular matrix material in ocular and non-ocular tissues, including blood vessel walls. Clot-forming dysfunction might be responsible for venous thrombosis in PEX. We investigated global coagulation, the proteome, and functions of platelets in PEX patients and aimed to determine prognostic biomarkers for thrombosis risk in PEX. Peripheral blood was collected from PEX and retinal vein occlusion (RVO) patients, and age-sex matched controls. Viscoelastic hemostasis was evaluated by rotational thromboelastometry (ROTEM). Platelet markers (CD41, CD42, CD61, and CD62p) and endothelial markers (P-selectin, E-selectin, and von Willebrand factor) were investigated by flow cytometry and ELISA, respectively. The platelet proteome was analyzed by 2D fluorescence difference gel electrophoresis followed by mass spectrometry. Clot formation time (CFT) is significantly reduced in PEX patients compared to the controls (p < 0.05). P-selectin levels were higher in PEX patients than in controls (p < 0.05); E-selectin and von Willebrand factor remained unchanged. The monitorization of CFT by ROTEM, and soluble P-selectin, may help assess thrombotic risk in PEX patients. Proteomic analysis revealed differential expression of Profilin-1 in platelets. Profilin-1 regulates the stability of actin-cytoskeleton and may contribute to impaired platelet hemostatic functions. Increased P-selectin levels together with impaired coagulation dynamics might be responsible for the thrombotic events in PEX disease.


Assuntos
Síndrome de Exfoliação , Trombofilia , Humanos , Selectina-P , Profilinas , Proteoma , Fator de von Willebrand/metabolismo , Proteômica
8.
J Allergy Clin Immunol Pract ; 12(3): 599-604, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280450

RESUMO

Oral allergy syndrome or pollen food allergy syndrome (PFAS) represents a common clinical conundrum when the reported trigger food is a tree nut (usually almond or hazelnut) or peanut. The PFAS may give rise to uncertainty about the potential severity of the future reactions, indications for prescribing epinephrine, and the extent of the necessary dietary avoidance. As a food allergy, secondary to cross-reactivity with airborne pollen, PFAS usually manifests toward the end of the first decade of life as contact urticaria of the oropharyngeal mucous membranes. Molecular allergology facilitates diagnosis and risk stratification by establishing the profile of sensitization. Exclusive sensitization to pathogenesis-related proteins family 10 (PR10) and profilins indicates that signs and symptoms are due to PFAS, whereas sensitization to seed storage proteins with or without sensitization to PR10 and profilins may indicate a more severe primary nut allergy phenotype. Management relies on avoidance of the specific nut trigger, advice on the likelihood of more severe local or systemic symptoms, and treatment of reactions according to the severity. Future studies are needed to better delineate the risk of systemic reactions in individuals with nut PFAS and to establish the role of food or pollen allergen immunotherapy for the prevention or moderation of this condition.


Assuntos
Fluorocarbonos , Hipersensibilidade Alimentar , Hipersensibilidade a Noz , Humanos , Nozes , Profilinas , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/terapia , Hipersensibilidade a Noz/diagnóstico , Hipersensibilidade a Noz/terapia , Alérgenos , Pólen , Dessensibilização Imunológica , Síndrome
9.
Clin Transl Gastroenterol ; 15(1): e00651, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37787436

RESUMO

INTRODUCTION: Currently, the diagnosis of achalasia mainly relies on invasive or radioactive examinations. This study aimed to develop a noninvasive diagnostic method for achalasia based on specific serum markers. METHODS: Serum levels of profilin-1, galectin-10, immunoglobulin heavy variable 3-9, vasodilator-stimulated phosphoprotein, and transgelin-2 were measured in patients with achalasia and controls by enzyme-linked immunosorbent assay. The diagnostic values and thresholds were determined by the receiver operating characteristic curve analysis. Then, patients with dysphagia were prospectively enrolled to validate the ability of these molecules for achalasia diagnosing. RESULTS: A total of 142 patients with achalasia and 50 nonachalasia controls (healthy volunteers and patients with reflux esophagitis) were retrospectively included. The serum levels of profilin-1, galectin-10, and transgelin-2 in patients with achalasia were significantly higher than those in healthy volunteers and patients with reflux esophagitis ( P all < 0.001). Profilin-1, galectin-10, and transgelin-2 were of good performance in diagnosing achalasia, with optimal thresholds of 2,171.2, 33.9, and 1,630.6 pg/mL, respectively. Second, 40 patients with dysphagia were prospectively enrolled to the validation of achalasia. For profilin-1, the positive predictive value, negative predictive value, sensitivity, and specificity were 100.0%, 64.5%, 45.0%, and 100.0%, respectively. The figures for transgelin-2 were 65.5%, 90.9%, 95.0%, and 50.0%. When both increased, the positive predictive value reached to 100.0%. When both indexes were normal, the negative predictive value was 100.0%. DISCUSSION: Profilin-1 and transgelin-2 were promising biomarkers for achalasia diagnosis and performed better in combination. Further multicenter studies are necessary to verify their application as preliminary screening tools for achalasia.


Assuntos
Transtornos de Deglutição , Acalasia Esofágica , Esofagite Péptica , Humanos , Acalasia Esofágica/diagnóstico , Profilinas , Estudos Retrospectivos , Biomarcadores , Galectinas
10.
J Biol Chem ; 300(1): 105583, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141770

RESUMO

Membrane polyphosphoinositides (PPIs) are lipid-signaling molecules that undergo metabolic turnover and influence a diverse range of cellular functions. PPIs regulate the activity and/or spatial localization of a number of actin-binding proteins (ABPs) through direct interactions; however, it is much less clear whether ABPs could also be an integral part in regulating PPI signaling. In this study, we show that ABP profilin1 (Pfn1) is an important molecular determinant of the cellular content of PI(4,5)P2 (the most abundant PPI in cells). In growth factor (EGF) stimulation setting, Pfn1 depletion does not impact PI(4,5)P2 hydrolysis but enhances plasma membrane (PM) enrichment of PPIs that are produced downstream of activated PI3-kinase, including PI(3,4,5)P3 and PI(3,4)P2, the latter consistent with increased PM recruitment of SH2-containing inositol 5' phosphatase (SHIP2) (a key enzyme for PI(3,4)P2 biosynthesis). Although Pfn1 binds to PPIs in vitro, our data suggest that Pfn1's affinity to PPIs and PM presence in actual cells, if at all, is negligible, suggesting that Pfn1 is unlikely to directly compete with SHIP2 for binding to PM PPIs. Additionally, we provide evidence for Pfn1's interaction with SHIP2 in cells and modulation of this interaction upon EGF stimulation, raising an alternative possibility of Pfn1 binding as a potential restrictive mechanism for PM recruitment of SHIP2. In conclusion, our findings challenge the dogma of Pfn1's binding to PM by PPI interaction, uncover a previously unrecognized role of Pfn1 in PI(4,5)P2 homeostasis and provide a new mechanistic avenue of how an ABP could potentially impact PI3K signaling byproducts in cells through lipid phosphatase control.


Assuntos
Fosfatidilinositóis , Profilinas , Fator de Crescimento Epidérmico/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Fosfatidilinositóis/metabolismo , Humanos , Células HEK293 , Profilinas/metabolismo
11.
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
12.
J Cell Biol ; 222(12)2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37948068

RESUMO

Cellular actin networks exhibit a wide range of sizes, shapes, and architectures tailored to their biological roles. Once assembled, these filamentous networks are either maintained in a state of polarized turnover or induced to undergo net disassembly. Further, the rates at which the networks are turned over and/or dismantled can vary greatly, from seconds to minutes to hours or even days. Here, we review the molecular machinery and mechanisms employed in cells to drive the disassembly and turnover of actin networks. In particular, we highlight recent discoveries showing that specific combinations of conserved actin disassembly-promoting proteins (cofilin, GMF, twinfilin, Srv2/CAP, coronin, AIP1, capping protein, and profilin) work in concert to debranch, sever, cap, and depolymerize actin filaments, and to recharge actin monomers for new rounds of assembly.


Assuntos
Citoesqueleto de Actina , Actinas , Citoesqueleto de Actina/metabolismo , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Profilinas/genética , Profilinas/metabolismo , Mamíferos , Animais
13.
Cell Biol Toxicol ; 39(6): 2569-2586, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37953354

RESUMO

BACKGROUND: Urinary extracellular vesicles (EVs) have gained increasing interest in recent years as a potential source of noninvasive biomarkers of diseases related to urinary organs, but knowledge of the mechanism is still limited. The current study sought to clarify the mechanism of urinary EVs behind di-(2-ethylhexyl) phthalate (DEHP)-induced hypospadias via PFN2 delivery. METHOD: PFN2 expression in hypospadias was predicted by bioinformatics analysis. Following the induction of a hypospadias rat model using DEHP, rats were injected with EVs and/or underwent alteration of PFN2 and TGF-ß1 to assess their effects in vivo. The extracted rat urothelial cells (UECs) were co-cultured with EVs extracted from urine for in vitro experiments. RESULT: Microarray analysis predicted poor PFN2 expression in hypospadias. Upregulated PFN2 was found in urinary EVs, and restrained epithelial-mesenchymal transition (EMT) was observed in DEHP-exposed rats. Urinary EVs or PFN2 overexpression increased SMAD2, SMAD3, and TGF-ß1 protein expression and SMAD2 and SMAD3 phosphorylation in UECs and DEHP-exposed rats. UEC migration, invasion, and EMT were augmented by EV co-culture or upregulation of PFN2. Of note, the silencing of TGF-ß1 counterweighed the effect of PFN2. Besides, EV co-culture or overexpression of PFN2 or TGF-ß1 elevated the body weight, anal-genital distance (AGD), anal-genital index (AGI), and EMT of DEHP-exposed rats. CONCLUSION: In summary, urinary EVs activated the SMAD/TGF-ß1 pathway to induce EMT via PFN2 delivery, thus protecting against DEHP-induced hypospadias. (1) EMT in epithelial cells inhibits DEHP-induced hypospadias. (2) Urine-derived EVs deliver PFN2 to promote EMT in epithelial cells. (3) PFN2 can activate the SMAD/TGF-ß1 signaling axis. (4) Urine-derived EVs can transmit PFN2 to activate the SMAD/TGF-ß1 signaling axis, thus promoting EMT and inhibiting the occurrence of hypospadias.


Assuntos
Dietilexilftalato , Hipospadia , Humanos , Masculino , Ratos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Transição Epitelial-Mesenquimal , Hipospadia/induzido quimicamente , Dietilexilftalato/toxicidade , Profilinas/farmacologia
14.
Mol Cell Probes ; 72: 101937, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820747

RESUMO

Doxorubicin (DOX) often causes acute or chronic cardiotoxicity during its application. LncRNA RMRP has been reported to be associated with several biological processes, such as cartilage-hair hypoplasia, but the relationship between RMRP and DOX-induced cardiotoxicity and chronic heart failure remains obscure. To test this hypothesis, GSE124401 and GSE149870 were processed for bioinformatics, and differentially expressed RMRP was then verified in the peripheral blood of 21 patients with heart failure compared with 7 controls. For in vitro validation, we used AC16 and HEK-293T cells. qPCR was used to detect the mRNA expression levels. The degree of apoptosis was detected by Western blot and TUNEL staining. Furthermore, the interaction between RMRP and PFN1 mRNA was verified by dual-luciferase reporter assays. In bioinformatics, RMRP showed significant downregulation, which was verified in clinical samples (p < 0.001) and DOX-treated AC16 models (p < 0.0001). Next, overexpression of RMRP could significantly alleviate DOX-induced apoptosis, and a potential downstream molecule of RMRP, PFN1, was also negatively associated with this change. RESCUE experiments further confirmed that PFN1 could be regulated by RMRP at both the RNA and protein levels, serving as a downstream mediator of RMRP's cardioprotective effects. This interaction was then confirmed to be a direct combination (p < 0.0001). Finally, we found that overexpression of RMRP could inhibit the expression of p53 and its phosphorylation level by suppressing PFN1. In summary, RMRP could exert cardioprotective effects via the PFN1/p53 axis, holding great promise for serving as a therapeutic target and potential biomarker.


Assuntos
Insuficiência Cardíaca , MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/genética , Cardiotoxicidade/metabolismo , Doxorrubicina/farmacologia , Apoptose/genética , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , RNA Mensageiro , Profilinas/metabolismo , Profilinas/farmacologia
15.
J Clin Invest ; 133(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37847555

RESUMO

The progression of proteinuric kidney diseases is associated with podocyte loss, but the mechanisms underlying this process remain unclear. Podocytes reenter the cell cycle to repair double-stranded DNA breaks. However, unsuccessful repair can result in podocytes crossing the G1/S checkpoint and undergoing abortive cytokinesis. In this study, we identified Pfn1 as indispensable in maintaining glomerular integrity - its tissue-specific loss in mouse podocytes resulted in severe proteinuria and kidney failure. Our results suggest that this phenotype is due to podocyte mitotic catastrophe (MC), characterized histologically and ultrastructurally by abundant multinucleated cells, irregular nuclei, and mitotic spindles. Podocyte cell cycle reentry was identified using FUCCI2aR mice, and we observed altered expression of cell-cycle associated proteins, such as p21, p53, cyclin B1, and cyclin D1. Podocyte-specific translating ribosome affinity purification and RNA-Seq revealed the downregulation of ribosomal RNA-processing 8 (Rrp8). Overexpression of Rrp8 in Pfn1-KO podocytes partially rescued the phenotype in vitro. Clinical and ultrastructural tomographic analysis of patients with diverse proteinuric kidney diseases further validated the presence of MC podocytes and reduction in podocyte PFN1 expression within kidney tissues. These results suggest that profilin1 is essential in regulating the podocyte cell cycle and its disruption leads to MC and subsequent podocyte loss.


Assuntos
Nefropatias , Podócitos , Profilinas , Animais , Humanos , Camundongos , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Morte Celular/genética , Nefropatias/metabolismo , Glomérulos Renais/patologia , Podócitos/patologia , Profilinas/genética , Proteinúria/patologia
16.
J Biol Chem ; 299(12): 105367, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37863260

RESUMO

Cyclase-associated protein (CAP) has emerged as a central player in cellular actin turnover, but its molecular mechanisms of action are not yet fully understood. Recent studies revealed that the N terminus of CAP interacts with the pointed ends of actin filaments to accelerate depolymerization in conjunction with cofilin. Here, we use in vitro microfluidics-assisted TIRF microscopy to show that the C terminus of CAP promotes depolymerization at the opposite (barbed) ends of actin filaments. In the absence of actin monomers, full-length mouse CAP1 and C-terminal halves of CAP1 (C-CAP1) and CAP2 (C-CAP2) accelerate barbed end depolymerization. Using mutagenesis and structural modeling, we show that these activities are mediated by the WH2 and CARP domains of CAP. In addition, we observe that CAP collaborates with profilin to accelerate barbed end depolymerization and that these effects depend on their direct interaction, providing the first known example of CAP-profilin collaborative effects in regulating actin. In the presence of actin monomers, CAP1 attenuates barbed end growth and promotes formin dissociation. Overall, these findings demonstrate that CAP uses distinct domains and mechanisms to interact with opposite ends of actin filaments and drive turnover. Further, they contribute to the emerging view of actin barbed ends as sites of dynamic molecular regulation, where numerous proteins compete and cooperate with each other to tune polymer dynamics, similar to the rich complexity seen at microtubule ends.


Assuntos
Citoesqueleto de Actina , Actinas , Proteínas do Citoesqueleto , Forminas , Proteínas de Membrana , Animais , Camundongos , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Fatores de Despolimerização de Actina/genética , Fatores de Despolimerização de Actina/metabolismo , Actinas/química , Actinas/metabolismo , Forminas/metabolismo , Profilinas/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Polimerização , Domínios Proteicos/genética , Modelos Moleculares , Estrutura Terciária de Proteína
17.
Eur J Cell Biol ; 102(4): 151363, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37778219

RESUMO

In vitro reconstitution assays using purified actin have greatly improved our understanding of cytoskeletal dynamics and their regulation by actin-binding proteins. However, early purification methods consisted of harsh conditions to obtain pure actin and often did not include correct maturation and obligate modification of the isolated actin monomers. Novel insights into the folding requirements and N-terminal processing of actin as well as a better understanding of the interaction of actin with monomer sequestering proteins such as DNaseI, profilin and gelsolin, led to the development of more gentle approaches to obtain pure recombinant actin isoforms with known obligate modifications. This review summarizes the approaches that can be employed to isolate natively folded endogenous and recombinant actin from tissues and cells. We further emphasize the use and limitations of each method and describe how these methods can be implemented to study actin PTMs, disease-related actin mutations and novel actin-like proteins.


Assuntos
Actinas , Proteínas dos Microfilamentos , Animais , Actinas/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Profilinas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Mamíferos/metabolismo , Gelsolina/genética , Gelsolina/metabolismo
18.
Philos Trans R Soc Lond B Biol Sci ; 378(1890): 20220247, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37778386

RESUMO

Neutrophil adhesion to endothelia, entry into tissues and chemotaxis constitute essential steps in the immune response to infections that drive inflammation. Neutrophils bind to other cells and migrate via adhesion receptors, notably the αMß2 integrin dimer (also called Mac-1, CR3 or CD11b/CD18). Here, the response of neutrophils to integrin engagement was examined by monitoring the activity of peptidylarginine deiminase 4 (PAD4). Histone H3 deimination was strongly stimulated by manganese, an integrin-activating divalent cation, even in the absence of additional inflammatory stimuli. Manganese-induced cell attachment resulted in neutrophil swarm formation that paralleled histone deimination, whereas antibodies that impair integrin binding prevented both cell adhesion and histone deimination. Manganese treatment led to putative deimination of profilin, a protein that functions as an actin-organizing hub, as detected by two-dimensional gel electrophoresis and citrulline immunoblotting. Cl-amidine, a covalent inhibitor of PAD4, and GSK484, a specific PAD4 inhibitor, blocked profilin deimination. Neutrophil migration toward leukotriene B4 and toward synovial fluid from a rheumatoid arthritis patient were inhibited by chloramidine, thus supporting the contribution of deimination to chemotaxis. The data, based on a simplified system for integrin activation, imply a mechanism whereby integrin attachment coordinates neutrophil responses to inflammation and orchestrates deimination of nuclear and cytoskeletal proteins. This article is part of the Theo Murphy meeting issue 'The virtues and vices of protein citrullination'.


Assuntos
Histonas , Neutrófilos , Humanos , Histonas/metabolismo , Citrulinação , Profilinas/metabolismo , Integrinas/metabolismo , Manganês/metabolismo , Antígeno de Macrófago 1/genética , Antígeno de Macrófago 1/metabolismo , Inflamação/metabolismo
19.
Anal Chem ; 95(41): 15141-15145, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37787459

RESUMO

Profilin 1 (PFN1) is a cytoskeleton protein that modulates actin dynamics through binding to monomeric actin and polyproline-containing proteins. Mutations in PFN1 have been linked to the pathogenesis of familial amyotrophic lateral sclerosis (ALS). Here, we employed an unbiased proximity labeling strategy in combination with proteomic analysis for proteome-wide profiling of proteins that differentially interact with mutant and wild-type (WT) PFN1 proteins in human cells. We uncovered 11 mRNA splicing proteins that are preferentially enriched in the proximity proteomes of the two ALS-linked PFN1 variants, C71G and M114T, over that of wild-type PFN1. We validated the preferential interactions of the ALS-linked PFN1 variants with two mRNA splicing factors, hnRNPC and U2AF2, by immunoprecipitation, followed with immunoblotting. We also found that the two ALS-linked PFN1 variants promoted the exonization of Alu elements in the mRNAs of MTO1, TCFL5, WRN and POLE genes in human cells. Together, we showed that the two ALS-linked PFN1 variants interacted preferentially with mRNA splicing proteins, which elicited aberrant exonization of the Alu elements in mRNAs. Thus, our work provided pivotal insights into the perturbations of ALS-linked PFN1 variants in RNA biology and their potential contributions to ALS pathology.


Assuntos
Esclerose Amiotrófica Lateral , Humanos , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Profilinas/genética , Profilinas/metabolismo , Actinas/metabolismo , Proteômica , Mutação , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
20.
FASEB J ; 37(10): e23170, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37676718

RESUMO

Small cell lung cancer (SCLC) is one of the most malignant tumors that has an extremely poor prognosis. RNA-binding protein (RBP) and long noncoding RNA (lncRNA) have been shown to be key regulators during tumorigenesis as well as lung tumor progression. However, the role of RBP ELAVL4 and lncRNA LYPLAL1-DT in SCLC remains unclear. In this study, we verified that lncRNA LYPLAL1-DT acts as an SCLC oncogenic lncRNA and was confirmed in vitro and in vivo. Mechanistically, LYPLAL1-DT negatively regulates the expression of miR-204-5p, leading to the upregulation of PFN2, thus, promoting SCLC cell proliferation, migration, and invasion. ELAVL4 has been shown to enhance the stability of LYPLAL1-DT and PFN2 mRNA. Our study reveals a regulatory pathway, where ELAVL4 stabilizes PFN2 and LYPLAL1-DT with the latter further increasing PFN2 expression by blocking the action of miR-204-5p. Upregulated PFN2 ultimately promotes tumorigenesis and invasion in SCLC. These findings provide novel prognostic indicators as well as promising new therapeutic targets for SCLC.


Assuntos
Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Carcinoma de Pequenas Células do Pulmão , Humanos , RNA Longo não Codificante/genética , Profilinas/genética , Carcinoma de Pequenas Células do Pulmão/genética , Transformação Celular Neoplásica/genética , Carcinogênese/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteína Semelhante a ELAV 4
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