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BACKGROUND: Hepatic fibrosis, a prevalent chronic liver condition, involves excessive extracellular matrix production associated with aberrant wound healing. Hepatic stellate cells (HSCs) play a pivotal role in liver fibrosis, activated by inflammatory factors such as sphingosine 1-phosphate (S1P). Despite S1P's involvement in fibrosis, its specific role and downstream pathway in HSCs remain controversial. METHODS: In this study, we investigated the regulatory role of S1P/S1P receptor (S1PR) in Hippo-YAP activation in both LX-2 cell lines and primary HSCs. Real-time PCR, western blot, pharmacological inhibitors, siRNAs, and Rho activity assays were adopted to address the molecular mechanisms of S1P mediated YAP activation. RESULTS: Serum and exogenous S1P significantly increased the expression of YAP target genes in HSCs. Pharmacologic inhibitors and siRNA-mediated knockdowns of S1P receptors showed S1P receptor 2 (S1PR2) as the primary mediator for S1P-induced CTGF expression in HSCs. Results using siRNA-mediated knockdown, Verteporfin, and Phospho-Tag immunoblots showed that S1P-S1PR2 signaling effectively suppressed the Hippo kinases cascade, thereby activating YAP. Furthermore, S1P increased RhoA activities in cells and ROCK inhibitors effectively blocked CTGF induction. Cytoskeletal-perturbing reagents were shown to greatly modulate CTGF induction, suggesting the important role of actin cytoskeleton in S1P-induced YAP activation. Exogeneous S1P treatment was enough to increase the expression of COL1A1 and α-SMA, that were blocked by YAP specific inhibitor. CONCLUSIONS: Our data demonstrate that S1P/S1PR2-Src-RhoA-ROCK axis leads to Hippo-YAP activation, resulting in the up-regulation of CTGF, COL1A1 and α-SMA expression in HSCs. Therefore, S1PR2 may represent a potential therapeutic target for hepatic fibrosis.
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Factor de Crecimiento del Tejido Conjuntivo , Células Estrelladas Hepáticas , Lisofosfolípidos , Transducción de Señal , Esfingosina , Factores de Transcripción , Proteínas Señalizadoras YAP , Quinasas Asociadas a rho , Proteína de Unión al GTP rhoA , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/genética , Lisofosfolípidos/metabolismo , Lisofosfolípidos/farmacología , Humanos , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/genética , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Proteínas Señalizadoras YAP/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Receptores de Esfingosina-1-Fosfato/metabolismo , Receptores de Esfingosina-1-Fosfato/genética , Línea Celular , Cirrosis Hepática/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Familia-src Quinasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Receptores de Lisoesfingolípidos/metabolismo , Receptores de Lisoesfingolípidos/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Vía de Señalización HippoRESUMEN
The behavior and presence of actin-regulating proteins are characteristic of various clinical diseases. Changes in these proteins significantly impact the cytoskeletal and regenerative processes underlying pathological changes. Pituitary adenylate cyclase-activating polypeptide (PACAP), a cytoprotective neuropeptide abundant in the nervous system and endocrine organs, plays a key role in neuron differentiation and migration by influencing actin. This study aims to elucidate the role of PACAP as an actin-regulating polypeptide, its effect on actin filament formation, and the underlying regulatory mechanisms. We examined PACAP27, PACAP38, and PACAP6-38, measuring their binding to actin monomers via fluorescence spectroscopy and steady-state anisotropy. Functional polymerization tests were used to track changes in fluorescent intensity over time. Unlike PACAP27, PACAP38 and PACAP6-38 significantly reduced the fluorescence emission of Alexa488-labeled actin monomers and increased their anisotropy, showing nearly identical dissociation equilibrium constants. PACAP27 showed weak binding to globular actin (G-actin), while PACAP38 and PACAP6-38 exhibited robust interactions. PACAP27 did not affect actin polymerization, but PACAP38 and PACAP6-38 accelerated actin incorporation kinetics. Fluorescence quenching experiments confirmed structural changes upon PACAP binding; however, all studied PACAP fragments exhibited the same effect. Our findings indicate that PACAP38 and PACAP6-38 strongly bind to G-actin and significantly influence actin polymerization. Further studies are needed to fully understand the biological significance of these interactions.
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Actinas , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Espectrometría de Fluorescencia , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/química , Actinas/metabolismo , Actinas/química , Animales , Espectrometría de Fluorescencia/métodos , Citoesqueleto/metabolismo , Unión Proteica , Citoesqueleto de Actina/metabolismo , Humanos , CinéticaRESUMEN
Trichloromethane (TCM), a commonly recognized disinfection by-product formed during the chlorination of water, has been associated with the onset of colorectal cancer (CRC) in humans. Despite this, the impact of TCM on the progression of CRC remains uncertain. In this investigation, it was observed that exposure to TCM could augment the migratory capabilities of CRC cells and facilitate the advancement of colorectal tumors. To delve deeper into the mechanism responsible for TCM-induced CRC progression, we performed RNA-Seq analysis at cellular and animal levels after TCM exposure. Both the KEGG and GO enrichment analyses indicated the activation of endoplasmic reticulum stress (ERS) and the regulation of the cytoskeleton. Subsequently, we confirmed the activation of the IRE1α/XBP1 pathway of ERS through western blot and RT-qPCR. Additionally, we observed the aggregation of cytoskeletal proteins F-actin and ß-tubulin at the cell membrane periphery and the development of cellular pseudopods using immunofluorescence following exposure to TCM in vitro. The downregulation of IRE1α and XBP1 through siRNA interference resulted in the disruption of cell cytoskeleton rearrangement and impaired cell migration capability. Conversely, treatment with TCM mitigated this inhibitory effect. Moreover, chronic exposure to low concentration of TCM also triggered CRC cell migration by causing cytoskeletal reorganization, a process controlled by the IRE1α/XBP1 axis. Our study concludes that TCM exposure induces cell migration through the activation of ERS, which in turn regulates cytoskeleton rearrangement. This study offers novel insights into the mechanism through which TCM facilitates the progression of CRC.
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Cloroformo , Neoplasias Colorrectales , Estrés del Retículo Endoplásmico , Proteínas Serina-Treonina Quinasas , Proteína 1 de Unión a la X-Box , Animales , Humanos , Ratones , Línea Celular Tumoral , Estrés del Retículo Endoplásmico/efectos de los fármacos , Endorribonucleasas/metabolismo , Endorribonucleasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Transducción de Señal/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Proteína 1 de Unión a la X-Box/metabolismo , Proteína 1 de Unión a la X-Box/genética , Cloroformo/toxicidad , Agua PotableRESUMEN
Cellular reprogramming technologies have been developed with different physicochemical factors to improve the reprogramming efficiencies of induced pluripotent stem cells (iPSCs). Ultrasound is a clinically applied noncontact biophysical factor known for regulating various cellular behaviors but remains uninvestigated for cellular reprogramming. Here, we present a new reprogramming strategy using low-intensity ultrasound (LIUS) to improve cellular reprogramming of iPSCs in vitro and in vivo. Under 3D microenvironment conditions, increased LIUS stimulation shows enhanced cellular reprogramming of the iPSCs. The cellular reprogramming process facilitated by LIUS is accompanied by increased mesenchymal to epithelial transition and histone modification. LIUS stimulation transiently modulates the cytoskeletal rearrangement, along with increased membrane fluidity and mobility to increase HA/CD44 interactions. Furthermore, LIUS stimulation with HA hydrogel can be utilized in application of both human cells and in vivo environment, for enhanced reprogrammed cells into iPSCs. Thus, LIUS stimulation with a combinatorial 3D microenvironment system can improve cellular reprogramming in vitro and in vivo environments, which can be applied in various biomedical fields.
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Rearrangement of the actin cytoskeleton is a prerequisite for carcinoma cells to develop cellular protrusions, which are required for migration, invasion, and metastasis. Fascin is a key protein involved in actin bundling and is expressed in aggressive and invasive carcinomas. Additionally, fascin appears to be involved in tubulin-binding and microtubule rearrangement. Pharmacophoric-based in silico screening was performed to identify compounds with better fascin inhibitory properties than migrastatin, a gold-standard fascin inhibitor. We hypothesized that monastrol displays anti-migratory and anti-invasive properties via fascin blocking in colorectal cancer cell lines. Biophysical (thermofluor and ligand titration followed by fluorescence spectroscopy), biochemical (NMR), and cellular assays (MTT, invasion of human tissue), as well as animal model studies (zebrafish invasion) were performed to characterize the inhibitory effect of monastrol on fascin activity. In silico analysis revealed that monastrol is a potential fascin-binding compound. Biophysical and biochemical assays demonstrated that monastrol binds to fascin and interferes with its actin-bundling activity. Cell culture studies, including a 3D human myoma disc model, showed that monastrol inhibited fascin-driven cytoplasmic protrusions as well as invasion. In silico, confocal microscopy, and immunoprecipitation assays demonstrated that monastrol disrupted fascin-tubulin interactions. These anti-invasive effects were confirmed in vivo. In silico confocal microscopy and immunoprecipitation assays were carried out to test whether monastrol disrupted the fascin-tubulin interaction. This study reports, for the first time, the in vitro and in vivo anti-invasive properties of monastrol in colorectal tumor cells. The number and types of interactions suggest potential binding of monastrol across actin and tubulin sites on fascin, which could be valuable for the development of antitumor therapies.
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Proteínas Portadoras , Neoplasias Colorrectales , Cinesinas , Proteínas de Microfilamentos , Invasividad Neoplásica , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Proteínas de Microfilamentos/metabolismo , Proteínas Portadoras/metabolismo , Cinesinas/metabolismo , Cinesinas/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Metástasis de la Neoplasia/prevención & control , Pirimidinas/farmacología , Transducción de Señal/efectos de los fármacos , Tionas/farmacología , Antineoplásicos/farmacologíaRESUMEN
Overexpression of epidermal growth factor receptor (EGFR) in cancer is a key cause of recurrence of cervical cancer (CC). Although the EGF-EGFR pathway has been studied for decades, preventing tumor growth and recurrence caused by peripheral EGF remains a great challenge. In this work, a strategy is proposed to reduce the stimulation of high concentration EGF on tumor growth by using a thermo-sensitive hydrogel. The hydrogel is a triblock copolymer composed of polyethylene glycol (PEG) and poly (lactide glycolide) (PLGA). Based on the excellent temperature sensitivity, carrier capacity, swelling property and biocompatibility, the hydrogel can absorb the liquid around the tumor by injection and release EGF continuously at low concentration. The inhibitory effect of hydrogel on tumor growth is fully confirmed by an implanted tumor mouse model with human cervical cancer cell lines (HeLa) using triple-immunodeficient NCG mice. Compared with free EGF, the EGF-loaded hydrogel can hardly induce surface plasmon resonance (SPR) response, which proves that hydrogel can effectively weaken cytoskeleton rearrangement and inhibit cell migration by continuously releasing low concentration EGF. In addition, the EGF-loaded hydrogel can reduce cell proliferation by delaying the progress of cell cycle progression. Taken together, the hydrogel can effectively protect tumor microenvironment from the stimulation of high concentration EGF, delay cancer cellular processes and tumor growth, and thus providing an approach for inhibiting tumor recurrence of CC.
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Poliésteres , Neoplasias del Cuello Uterino , Femenino , Ratones , Humanos , Animales , Neoplasias del Cuello Uterino/tratamiento farmacológico , Factor de Crecimiento Epidérmico , Preparaciones de Acción Retardada , Polietilenglicoles , Hidrogeles/farmacología , Materiales Biocompatibles , Células HeLa , Receptores ErbB , Microambiente TumoralRESUMEN
Angiotensin receptor blockers (ARBs) are the first-line treatment for hypertension; they act by inhibiting signaling through the angiotensin 1 receptor (AT1R). Recently, a novel biased AT1R agonist, TRV120027 (TRV), which selectively activates the ß-arrestin cascade and blocks the G-protein-coupled receptor pathway has been proposed as a potential blood pressure medication. Here, we explored the effects of TRV and associated ß-arrestin signaling in podocytes, essential cells of the kidney filter. We used human podocyte cell lines to determine ß-arrestin's involvement in calcium signaling and cytoskeletal reorganization and Dahl SS rats to investigate the chronic effects of TRV administration on glomerular health. Our experiments indicate that the TRV-activated ß-arrestin pathway promotes the rapid elevation of intracellular Ca2+ in a dose-dependent manner. Interestingly, the amplitude of ß-arrestin-mediated Ca2+ influx was significantly higher than the response to similar Ang II concentrations. Single-channel analyses show rapid activation of transient receptor potential canonical (TRPC) channels following acute TRV application. Furthermore, the pharmacological blockade of TRPC6 significantly attenuated the ß-arrestin-mediated Ca2+ influx. Additionally, prolonged activation of the ß-arrestin pathway in podocytes resulted in pathological actin cytoskeleton rearrangements, higher apoptotic cell markers, and augmented glomerular damage. TRV-activated ß-arrestin signaling in podocytes may promote TRPC6 channel-mediated Ca2+ influx, foot process effacement, and apoptosis, possibly leading to severe defects in glomerular filtration barrier integrity and kidney health. Under these circumstances, the potential therapeutic application of TRV for hypertension treatment requires further investigation to assess the balance of the benefits versus possible deleterious effects and off-target damage.
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Hipertensión , Enfermedades Renales , Podocitos , Ratas , Animales , Humanos , Podocitos/metabolismo , Canal Catiónico TRPC6/metabolismo , Calcio/metabolismo , beta-Arrestinas/metabolismo , Antagonistas de Receptores de Angiotensina/farmacología , Ratas Endogámicas Dahl , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Enfermedades Renales/metabolismo , Hipertensión/metabolismo , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/farmacologíaRESUMEN
Swine coronaviruses include the following six members, namely porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine delta coronavirus (PDCoV), swine acute diarrhea syndrome coronavirus (SADS-CoV), porcine hemagglutinating encephalomyelitis virus (PHEV), and porcine respiratory coronavirus (PRCV). Clinically, PEDV, TGEV, PDCoV, and SADS-CoV cause enteritis, whereas PHEV induces encephalomyelitis, and PRCV causes respiratory disease. Years of studies reveal that swine coronaviruses replicate in the cellular cytoplasm exerting a wide variety of effects on cells. Some of these effects are particularly pertinent to cell pathology, including endoplasmic reticulum (ER) stress, unfolded protein response (UPR), autophagy, and apoptosis. In addition, swine coronaviruses are able to induce cellular changes, such as cytoskeletal rearrangement, alterations of junctional complexes, and epithelial-mesenchymal transition (EMT), that render enterocytes unable to absorb nutrients normally, resulting in the loss of water, ions, and protein into the intestinal lumen. This review aims to describe the cellular changes in swine coronavirus-infected cells and to aid in understanding the pathogenesis of swine coronavirus infections. This review also explores how the virus exerted subcellular and molecular changes culminating in the clinical and pathological findings observed in the field.
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Tire wear microplastic particles (TWMPs) are emerging microplastic pollutants that have gained increasing attention lately. However, the health effect of inhaled airborne TWMPs has never been explored before and may already be included in particulate matter morbidity and mortality. Here, we endeavored to address the preliminary study of TWMP inhalation-induced pulmonary toxic effects and its epigenetic mechanisms in C57BL/6 mice. As a result, restricted ventilatory dysfunction and fibrotic pathological changes were observed in TWMP-treaded mice. Further research found that attenuation of miR-1a-3p plays an important role in TWMP-induced lung injury. Results from in vitro study confirmed that cytoskeleton regulatory gene twinfilin-1 was one of the target genes of miR-1a-3p, and involved in cytoskeleton rearrangement caused by TWMP exposure. Mechanistically, miR-1a-3p inhibited the F-actin formation by targeting cytoskeletal regulatory proteins twinfilin-1, leading to TWMP-induced pulmonary fibrotic injury. While we are in the very early stages of explaining the role of epigenetics in TWMP-induced lung injury, the potential for the use of epigenetic marks as biomarkers is high and discoveries made in this field will likely bring us closer to better understanding this crucial mechanism.
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Lesión Pulmonar , MicroARNs , Animales , Citoesqueleto/metabolismo , Lesión Pulmonar/inducido químicamente , Lesión Pulmonar/metabolismo , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Microplásticos , Plásticos/metabolismoRESUMEN
Cytoskeletal proteins are essential in maintaining cell morphology, proliferation, and viability as well as internalizing molecules in phagocytic and non-phagocytic cells. Orderly aligned cytoskeletons are disturbed by a range of biological processes, such as the epithelial-mesenchymal transition, which is observed in cancer metastasis. Although many biological methods have been developed to detect cytoskeletal rearrangement, simple and quantitative in vitro approaches are still in great demand. Herein, we applied a flow cytometry-based nanoparticle uptake assay to measure the degree of cytoskeletal rearrangement induced by transforming growth factor ß1 (TGF-ß1). For the assay, silica nanoparticles, selected for their high biocompatibility, were fluorescent-labeled to facilitate quantification with flow cytometry. Human keratinocyte HaCaT cells were treated with different concentrations of TGF-ß1 and then exposed to FITC-labeled silica nanoparticles. Increasing concentrations of TGF-ß1 induced gradual changes in cytoskeletal rearrangement, as confirmed by conventional assays. The level of nanoparticle uptake increased by TGF-ß1 treatment in a dose-dependent manner, indicating that our nanoparticle uptake assay can be used as a quick and non-destructive approach to measure cytoskeletal rearrangement.
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BACKGROUND: Endometrial cancer, one of the most common malignant tumors, is a serious threat to women's health. Endometrial hyperplasia is a precursor of endometrial cancer. S100 calcium binding protein P (S100P) has been found to play important roles in many types of cancer. The present study aimed to investigate the expression of S100P in endometrial cancer and its precursor lesions, and to explore the possible mechanisms. METHODS: We collected paraffin sections of normal endometrium, simple and complex non-atypical hyperplasia, atypical hyperplasia, and endometrioid carcinoma. The expression of S100P in endometrial cancer and its precancerous lesions was observed using immunohistochemistry. We also cultured primary endometrial cells and endometrial cancer cell lines (Ishikawa and RL95-2), and observed the expression of S100P in these cells. Laser confocal microscopy was used to observe the co-localization of S100P and its interacting protein Ezrin in RL95-2 cells. We employed lentiviruses to knockdown and overexpress S100P and then detected the F-actin distribution and cell invasion using phalloidin staining and Transwell assays. RESULTS: There was a gradual increase in the S100P signal as the disease progressed from normal endometrium and simple non-atypical hyperplasia, to complex non-atypical hyperplasia, atypical hyperplasia, and then to endometrial cancer. S100P was mainly distributed in the cytoplasm and co-localized with Ezrin in endometrial cancer cells. After knocking down S100P, F-actin aggregated in the nucleus or to the local cell membrane. Furthermore, knockdown of S100P in Ishikawa cells decreased their cell invasion capability. Meanwhile, S100P overexpression in endometrial stromal cells increased cell invasion. CONCLUSIONS: These data suggested that S100P might be involved in the occurrence and development of endometrial cancer via interaction with Ezrin and re-organization of F-actin to promote cell invasion.
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Proteínas de Unión al Calcio/metabolismo , Carcinoma Endometrioide/metabolismo , Progresión de la Enfermedad , Neoplasias Endometriales/metabolismo , Proteínas de Neoplasias/metabolismo , Lesiones Precancerosas/metabolismo , Actinas/metabolismo , Adulto , Proteínas de Unión al Calcio/genética , Carcinoma Endometrioide/patología , Línea Celular Tumoral , Proteínas del Citoesqueleto/metabolismo , Neoplasias Endometriales/patología , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Inmunohistoquímica , Invasividad Neoplásica/genética , Proteínas de Neoplasias/genética , Lesiones Precancerosas/patología , Transducción de Señal/genética , Transfección , Adulto JovenRESUMEN
Porcine hemagglutinating encephalomyelitis virus (PHEV) is a highly neurotropic virus that causes diffuse neuronal infection with neurological damage and high mortality. Virus-induced cytoskeletal dynamics are thought to be closely related to this type of nerve damage. Currently, the regulation pattern of the actin cytoskeleton and its molecular mechanism remain unclear when PHEV enters the host cells. Here, we demonstrate that entry of PHEV into N2a cells induces a biphasic remodeling of the actin cytoskeleton and a dynamic change in cofilin activity. Viral entry is affected by the disruption of actin kinetics or alteration of cofilin activity. PHEV binds to integrin α5ß1 and then initiates the integrin α5ß1-FAK signaling pathway, leading to virus-induced early cofilin phosphorylation and F-actin polymerization. Additionally, Ras-related C3 botulinum toxin substrate 1 (Rac1), cell division cycle 42 (Cdc42), and downstream regulatory gene p21-activated protein kinases (PAKs) are recruited as downstream mediators of PHEV-induced dynamic changes of the cofilin activity pathway. In conclusion, we demonstrate that PHEV utilizes the integrin α5ß1-FAK-Rac1/Cdc42-PAK-LIMK-cofilin pathway to cause an actin cytoskeletal rearrangement to promote its own invasion, providing theoretical support for the development of PHEV pathogenic mechanisms and new antiviral targets.IMPORTANCE PHEV, a member of the Coronaviridae family, is a typical neurotropic virus that primarily affects the nervous system of piglets to produce typical neurological symptoms. However, the mechanism of nerve damage caused by the virus has not been fully elucidated. Actin is an important component of the cytoskeleton of eukaryotic cells and serves as the first obstacle to the entry of pathogens into host cells. Additionally, the morphological structure and function of nerve cells depend on the dynamic regulation of the actin skeleton. Therefore, exploring the mechanism of neuronal injury induced by PHEV from the perspective of the actin cytoskeleton not only helps elucidate the pathogenesis of PHEV but also provides a theoretical basis for the search for new antiviral targets. This is the first report to define a mechanistic link between alterations in signaling from cytoskeleton pathways and the mechanism of PHEV invading nerve cells.
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Citoesqueleto de Actina/metabolismo , Factores Despolimerizantes de la Actina/metabolismo , Betacoronavirus 1/metabolismo , Quinasa 1 de Adhesión Focal/metabolismo , Integrina alfa5beta1/metabolismo , Degeneración Nerviosa/veterinaria , Animales , Línea Celular , Infecciones por Coronavirus/patología , Degeneración Nerviosa/virología , Porcinos , Proteína de Unión al GTP cdc42/metabolismo , Quinasas p21 Activadas/metabolismoRESUMEN
BACKGROUND: The breakdown of alveolar barrier dysfunction contributes to Lipopolysaccharide stimulated pulmonary edema and acute lung injury. Actin cytoskeleton has been implicated to be critical in regulation of epithelial barrier. Here, we performed in vivo and in vitro study to investigate role of TLR4-p38 MAPK-Hsp27 signal pathway in LPS-induced ALI. METHODS: For in vivo studies, 6-8-week-old C57 mice were used, Bronchoalveolar lavage Fluid /Blood fluorescent ratio, wet-to-dry lung weight ratio, as well as protein concentrations and neutrophil cell counts in BALF were detected as either directly or indirectly indicators of pulmonary alveolar barrier dysfunction. And hematoxylin and eosin staining was performed to estimate pulmonary injury. The in vitro explorations of transepithelial permeability were achieved through transepithelial electrical resistance measurement and testing of FITC-Dextran transepithelial flux in A549. In addition, cytoskeletal rearrangement was tested through F-actin immunostaining. And SB203580 was used to inhibit p38 MAPK activation, while siRNA was administered to genetically knockdown specific protein. RESULTS: We showed that LPS triggered activation of p38 MAPK, rearrangement of cytoskeleton which resulted in severe epithelial hyperpermeability and lung edema. A549 pretreated with TLR4 siRNAãp38 MAPK siRNA and its inhibitor SB203580 displayed a lower permeability and fewer stress fibers formation after LPS stimulation, accompanied with lower phosphorylation level of p38 MAPK and Hsp27, which verified the involvement of TLR4-p38 MAPK-Hsp27 in LPS-evoked alveolar epithelial injury. Inhibition of p38 MAPK activity with SB203580 in vivo attenuated pulmonary edema formation and hyperpermeability in response to LPS. CONCLUSIONS: Our study demonstrated that LPS increased alveolar epithelial permeability both in vitro and in vivo and that TLR4- p38 MAPK- Hsp27 signal pathway dependent actin remolding was involved in this process.
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Lesión Pulmonar Aguda/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Transducción de Señal , Receptor Toll-Like 4/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Células A549 , Lesión Pulmonar Aguda/inducido químicamente , Animales , Líquido del Lavado Bronquioalveolar , Células Cultivadas , Humanos , Imidazoles/farmacología , Lipopolisacáridos , Pulmón/patología , Masculino , Ratones , Permeabilidad , Fosforilación , Piridinas/farmacologíaRESUMEN
The excessive recruitment and improper activation of polymorphonuclear neutrophils (PMNs) often induces serious injury of host tissues, leading to inflammatory disorders. Therefore, to understand the molecular mechanism on neutrophil recruitment possesses essential pathological and physiological importance. In this study, we found that physiological shear stress induces c-Abl kinase activation in neutrophils, and c-Abl kinase inhibitor impaired neutrophil crawling behavior on ICAM-1. We further identified Vav1 was a downstream effector phosphorylated at Y174 and Y267. Once activated, c-Abl kinase regulated the activity of Vav1, which further affected Rac1/PAK1/LIMK1/cofilin signaling pathway. Here, we demonstrate a novel signaling function and critical role of c-Abl kinase during neutrophil crawling under physiological shear by regulating Vav1. These findings provide a promising treatment strategy for inflammation-related disease by inactivation of c-Abl kinase to restrict neutrophil recruitment.
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Factores Despolimerizantes de la Actina/metabolismo , Movimiento Celular , Quinasas Lim/metabolismo , Neutrófilos/metabolismo , Proteínas Proto-Oncogénicas c-abl/metabolismo , Resistencia al Corte , Transducción de Señal , Quinasas p21 Activadas/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Femenino , Células HEK293 , Humanos , Masculino , Neutrófilos/citologíaRESUMEN
Intraglomerular mesangial cells (MCs) maintain structural and functional integrity of renal glomerular microcirculation and homeostasis of mesangial matrix. Following different types of injury, MCs change their phenotype upregulating the expression of α-smooth muscle actin (α-SMA), changing contractile abilities and increasing the production of matrix proteins, chemokines and cytokines. CCL2 is a chemokine known to be involved in the pathogenesis of renal diseases. Its glomerular upregulation correlates with the extent of renal damage. Bindarit is an indazolic derivative endowed with anti-inflammatory activity when tested in experimental diseases. It selectively inhibits the synthesis of inflammatory C-C chemokines including CCL2, CCL7 and CCL8. This work aims to analyse bindarit effects on ET1-, AngII- and TGFß-induced mesangial cell dysfunction. Bindarit significantly reduced AngII-, ET1- and TGFß-induced α-SMA upregulation. In a collagen contraction assay, bindarit reduced AngII-, ET1- and TGFß-induced HRMC contraction. Within 3-6h stimulation, vinculin organization and phosphorylation was significantly impaired by bindarit in AngII-, ET1- and TGFß-stimulated cells without any effect on F-actin distribution. Conversely, p38 phosphorylation was not significantly inhibited by bindarit. Our data strengthen the importance of CCL2 on ET-1, AngII- and TGFß-induced mesangial cell dysfunction, adding new insights into the cellular mechanisms responsible of bindarit protective effects in human MC dysfunction.
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Quimiocinas/metabolismo , Citoesqueleto/efectos de los fármacos , Indazoles/farmacología , Células Mesangiales/efectos de los fármacos , Propionatos/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Actinas/metabolismo , Angiotensina II/metabolismo , Antiinflamatorios/farmacología , Células Cultivadas , Citoesqueleto/metabolismo , Endotelina-1/metabolismo , Mesangio Glomerular/efectos de los fármacos , Mesangio Glomerular/metabolismo , Humanos , Ligandos , Células Mesangiales/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
The purpose of this study was to assess the cytotoxic potential of a novel piperazine derivative (PCC) against human liver cancer cells. SNU-475 and 423 human liver cancer cell lines were used to determine the IC50 of PCC using the standard MTT assay. PCC displayed a strong suppressive effect on liver cancer cells with an IC50 value of 6.98 ± 0.11 µM and 7.76 ± 0.45 µM against SNU-475 and SNU-423 respectively after 24 h of treatment. Significant dipping in the mitochondrial membrane potential and elevation in the released of cytochrome c from the mitochondria indicated the induction of the intrinsic apoptosis pathway by PCC. Activation of this pathway was further evidenced by significant activation of caspase 3/7 and 9. PCC was also shown to activate the extrinsic pathways of apoptosis via activation of caspase-8 which is linked to the suppression of NF-κB translocation to the nucleus. Cell cycle arrest in the G1 phase was confirmed by flow cytometry and up-regulation of glutathione reductase expression was quantified by qPCR. Results of this study suggest that PCC is a potent anti-cancer agent inducing both intrinsic and extrinsic pathways of apoptosis in liver cancer cell lines.
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In diabetic nephropathy (DN), podocyte cytoskeletal rearrangement occurs followed by podocyte effacement and the development of proteinuria. PTEN (phosphatase and tensin homologue) is a ubiquitously expressed phosphatase that plays a critical role in cell proliferation, cytoskeletal rearrangement, and motility. In mouse models of diabetes mellitus, PTEN expression is reportedly decreased in mesangial cells, contributing to expansion of the mesangial matrix, but how PTEN in the podocyte influences the development of DN is unknown. We observed that PTEN expression is down-regulated in the podocytes of diabetic db/db mice and patients with DN. In cultured podocytes, PTEN inhibition caused actin cytoskeletal rearrangement and this response was associated with unbalanced activation of the small GTPases Rac1/Cdc42 and RhoA. In mice treated with PTEN inhibitor, actin cytoskeletal rearrangement occurred in podocytes and was accompanied by increased albumin excretion. We also created mice with an inducible deletion of PTEN selectively in podocytes. These mice exhibited increased albumin excretion and moderate foot process effacement. When the mice were challenged with a high fat diet, podocyte-specific knockout of PTEN resulted in substantially increased proteinuria and glomeruloclerosis compared to control mice fed a high fat diet or mice with PTEN deletion fed a normal diet. These results indicate that PTEN is involved in the regulation of cytoskeletal rearrangement in podocytes and that loss of PTEN predisposes to the development of proteinuria and DN.
Asunto(s)
Citoesqueleto/patología , Nefropatías Diabéticas/metabolismo , Fosfohidrolasa PTEN/metabolismo , Podocitos/metabolismo , Albuminuria/metabolismo , Animales , Citoesqueleto/metabolismo , Nefropatías Diabéticas/patología , Modelos Animales de Enfermedad , Mesangio Glomerular/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Ratones , Podocitos/patologíaRESUMEN
Osteoporosis is an aging-associated disease requiring better therapeutic modality. Eupatilin is a major flavonoid from Artemisia plants such as Artemisia princeps and Artemisia argyi which has been reported to possess various beneficial biological effects including anti-inflammation, anti-tumor, anti-cancer, anti-allergy, and anti-oxidation activity. Complete blockade of RANK-dependent osteoclastogenesis was accomplished upon stimulation prior to the receptor activator of nuclear factor κB (RANK)-ligand (RANKL) treatment or post-stimulation of bone marrow macrophages (BMCs) in the presence of RANKL with eupatilin. This blockade was accompanied by inhibition of rapid phosphorylation of Akt, GSK3ß, ERK and IκB as well as downregulation of c-Fos and NFATc1 at protein, suggesting that transcriptional suppression is a key mechanism for anti-osteoclastogenesis. Transient reporter assays or gain of function assays confirmed that eupatilin was a potent transcriptional inhibitor in osteoclasts (OC). Surprisingly, when mature osteoclasts were cultured on bone scaffolds in the presence of eupatilin, bone resorption activity was also completely blocked by dismantling the actin rings, suggesting that another major acting site of eupatilin is cytoskeletal rearrangement. The eupatilin-treated mature osteoclasts revealed a shrunken cytoplasm and accumulation of multi-nuclei, eventually becoming fibroblast-like cells. No apoptosis occurred. Inhibition of phosphorylation of cofilin by eupatilin suggests that actin may play an important role in the morphological change of multinucleated cells (MNCs). Human OC similarly responded to eupatilin. However, eupatilin has no effects on osteoblast differentiation and shows cytotoxicity on osteoblast in the concentration of 50 µM. When eupatilin was administered to LPS-induced osteoporotic mice after manifestation of osteoporosis, it prevented bone loss. Ovariectomized (OVX) mice remarkably exhibited bone protection effects. Taken together, eupatilin is an effective versatile therapeutic intervention for osteoporosis via; 1) transcriptional suppression of c-Fos and NFATc1 of differentiating OC and 2) inhibition of actin rearrangement of pathogenic MNCs.
RESUMEN
Human periodontal ligament cells (hPDLCs) form specialised connective tissues that influence the lifespan of the tooth. Periodontal disease is a chronic infectious disease of the periodontal supporting tissues caused by a variety of factors, particularly the loss of hPDLCs. Transforming growth factor-ß1 (TGF-ß1) is a multifunctional cytokine known to play an important role in periodontal disease, but little is known about the effects of TGF-ß1 on human PDL cells. To determine how TGF-ß1 mediates the changes in hPDLCs, we characterised the effects of TGF-ß1 treatment on hPDLCs. We then elucidated the signalling pathway that mediates these effects. Serum-starved hPDLCs were incubated with 10ng/mL TGF-ß1, and their proliferation was examined using the Cell Counting Kit-8, while their morphological changes were examined by phase-contrast microscopy. F-actin reorganisation was visualised by phalloidin staining and confocal microscopy. Protein expression was analysed by western blotting. We found that TGF-ß1 treatment induced proliferation and cytoskeletal reorganisation, decreased Rho-GDIa protein expression, activated ROCK protein expression, and increased the phosphorylation of LIM kinase and cofilin. Proliferation and cytoskeletal rearrangement were suppressed by pre-treatment with the ROCK inhibitor Y-27632; additionally, expression of ROCK protein and phosphorylation of LIM kinase and cofilin were decreased by Y-27632, while Rho-GDIa knockdown by targeted siRNA transfection causes opposite effects. Therefore, we propose that TGF-ß1 induces proliferation and cytoskeletal rearrangement in hPDLCs via Rho GTPase-dependent pathways that modulate ROCK, LIM kinase, and cofilin activity.