RESUMO
The roles of fibronectin leucine-rich transmembrane protein 2 (FLRT2) in physiological and pathological processes are not well known. Here, we identify a potentially novel function of FLRT2 in preventing endothelial cell senescence and vascular aging. We found that FLRT2 expression was lower in cultured senescent endothelial cells as well as in aged rat and human vascular tissues. FLRT2 mediated endothelial cell senescence via the mTOR complex 2, AKT, and p53 signaling pathway in human endothelial cells. We uncovered that FLRT2 directly associated with integrin subunit beta 4 (ITGB4) and thereby promoted ITGB4 phosphorylation, while inhibition of ITGB4 substantially mitigated the induction of senescence triggered by FLRT2 depletion. Importantly, FLRT2 silencing in mice promoted vascular aging, and overexpression of FLRT2 rescued a premature vascular aging phenotype. Therefore, we propose that FLRT2 could be targeted therapeutically to prevent senescence-associated vascular aging.
Assuntos
Células Endoteliais , Proteína Supressora de Tumor p53 , Animais , Humanos , Camundongos , Ratos , Envelhecimento , Células Endoteliais/metabolismo , Integrina beta4/genética , Integrina beta4/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Glicoproteínas de Membrana/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Immunomodulation is an essential consideration for cell replacement procedures. Unfortunately, lifelong exposure to nonspecific systemic immunosuppression results in immunodeficiency and has toxic effects on nonimmune cells. Here, we engineered hybrid spheroids of mesenchymal stem cells (MSCs) with rapamycin-releasing poly(lactic-co-glycolic acid) microparticles (RAP-MPs) to prevent immune rejection of islet xenografts in diabetic C57BL/6 mice. Hybrid spheroids were rapidly formed by incubating cell-particle mixture in methylcellulose solution while maintaining high cell viability. RAP-MPs were uniformly distributed in hybrid spheroids and sustainably released RAP for ~3 weeks. Locoregional transplantation of hybrid spheroids containing low doses of RAP-MPs (200- to 4000-ng RAP per recipient) significantly prolonged islet survival times and promoted the generation of regional regulatory T cells. Enhanced programmed death-ligand 1 expression by MSCs was found to be responsible for the immunomodulatory performance of hybrid spheroids. Our results suggest that these hybrid spheroids offer a promising platform for the efficient use of MSCs in the transplantation field.
Assuntos
Células-Tronco Mesenquimais , Esferoides Celulares , Animais , Humanos , Imunomodulação , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transplante HeterólogoRESUMO
OBJECTIVE: Human cervical cancer oncogene (HCCR)-1, previously identified in cervical cancer and its cell lines, has been reported to play an important role in tumor progression in several cancers as a suppressor of apoptosis. However, the role of HCCR-1 in the tumorigenesis of stomach cancer has not been identified. This study examined the role of HCCR-1 as a suppressor of apoptosis during tumorigenesis in gastric cancer, along with its possible regulatory pathway. METHODS: We employed several techniques including western blotting, semiquantitative reverse transcription polymerase chain reaction, diphenyltetrazolium bromide assay, chromatin immunoprecipitation assay, fluorescence-activated cell sorting, and HCCR-1 knockdown with short hairpin RNA to elucidate the role of HCCR-1. RESULTS: We observed that hepatocyte growth factor (HGF) upregulated HCCR-1 expression. In addition, the expression levels of ß-catenin, T cell factor-1 (TCF1), and B-cell lymphoma 2 (bcl2) were increased, whereas that of tumor protein 53 (p53) was decreased following HGF treatment. HCCR-1 knockdown in NUGC-3 and MKN-28 cells decreased the expression of TCF1 and phosphorylated ß-catenin and increased the binding activity on the binding site of the HCCR-1 promoter. This identifies the possible involvement of the Wnt/ß-catenin pathway in HGF-induced HCCR-1 regulation. We also confirmed the role of HCCR-1 in HGF-induced anti-apoptotic activity. p53 protein expression was increased, whereas that of bcl2 was decreased with HGF treatment in HCCR-1 knockdown cells, while the apoptotic activity was increased. CONCLUSION: Our study suggests the anti-apoptotic activity of HGF-induced HCCR-1 expression and that HGF may regulate HCCR-1 via TCF1/ß-catenin in stomach cancer.
RESUMO
Electrochemical biosensors have shown great potential for simple, fast, and cost-effective point-of-care diagnostic tools. However, direct analysis of complex biological fluids such as plasma has been limited by the loss of sensitivity caused by biofouling. By increasing the surface area, the nanostructured electrode can improve detection sensitivity. However, like a double-edged sword, a large surface area increases the nonspecific adsorption of contaminating proteins. The use of nanoporous structures may prevent fouling proteins. However, there is no straightforward approach for creating nanostructured and nanoporous surfaces compatible with microfabricated thin-film electrodes. Herein, the preferential etching of chloride and surfactant-assisted anisotropic gold reduction to create homogeneous, nanostructured, and nanoporous gold electrodes is demonstrated, yielding a 190 ± 20 times larger surface area within a minute without using templates. This process, "surfactant-based electrochemical etch-deposit interplay for nanostructure/nanopore growth" (SEEDING), on electrodes enhances the sensitivity and antibiofouling capabilities of amperometric biosensors, enabling direct analysis of tumor-derived extracellular vesicles (tEVs) in complex biofluids with a limit of detection of 300 tEVs µL-1 from undiluted plasma and good discrimination between patients with prostate cancer from healthy ones with an area under the curve of 0.91 in urine and 0.90 in plasma samples.
Assuntos
Técnicas Biossensoriais , Nanoporos , Biomarcadores , Técnicas Eletroquímicas , Eletrodos , Ouro/química , Humanos , Proteínas , TensoativosRESUMO
BACKGROUND/AIM: The 14-3-3 protein family has a variety of functions in cellular responses in different organisms, including cell-cycle regulation, apoptosis, and malignant transformation. 14-3-3 Sigma protein (14-3-3σ) induces G2 arrest, which enables repair of damaged DNA. The purpose of this study was to identify the role of 14-3-3σ up-regulation by hepatocyte growth factor (HGF) in cancer cell proliferation and invasion in gastric cancer. MATERIALS AND METHODS: In this study, cell culture, western blotting, real-time polymerase chain reaction, zymography, 14-3-3σ knock-down using short hairpin RNA (shRNA), electrophoresis mobility-shift assay, chromatin immunoprecipitation assay and standard two-chamber invasion assay were applied. RESULTS: Firstly, we confirmed that the expression of 14-3-3σ in gastric cancer cells was up-regulated by HGF. To identify how HGF-induced 14-3-3σ expression affects matrix metalloproteinase-1 (MMP1) expression, the cells were treated with the mitogen-activated protein kinase kinase inhibitor PD098059 and analyzed using western blotting. The HGF-mediated expression of MMP1 protein decreased in the presence of PD098059. The role of 14-3-3σ in MMP1 expression was determined through 14-3-3σ knockdown using shRNA. 14-3-3σ-shRNA cells showed reduced levels of MMP1, phosphorylated extracellular signal-regulated kinase, and pp38. HGF-mediated cell proliferation and in vitro invasion were reduced in 14-3-3σ knockdown cells. Serum 14-3-3σ levels were also significantly reduced following gastrectomy in patients with stage II or stage III gastric cancer (p<0.05). CONCLUSION: These results suggest that 14-3-3σ plays an important role in cell proliferation and metastasis in gastric cancer, and 14-3-3σ may be a novel target for detection and prevention of progression of gastric cancer. In addition, the serum 14-3-3σ level is associated with treatment status in patients with locally advanced gastric cancer.
Assuntos
Proteínas 14-3-3/genética , Exorribonucleases/genética , Fator de Crescimento de Hepatócito/genética , Metaloproteinase 1 da Matriz/genética , Neoplasias Gástricas/genética , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transdução de Sinais , Neoplasias Gástricas/patologiaRESUMO
Cellular senescence is caused by a wide range of intracellular and extracellular stimuli and influences physiological functions, leading to the progression of age-related diseases. Many studies have shown that cellular senescence is related to phosphatase and tension homolog deleted on chromosome ten (PTEN) loss and mammalian target of rapamycin (mTOR) activation. Although it has been reported that mTOR complex 1 (mTORC1) is major anti-aging target in several cell types, the functions and mechanisms of mTOR complex 2 (mTORC2) during aging have not been elucidated in vascular smooth muscle cells (VSMCs). Therefore, the aim of this study was to reveal the relationship between PTEN and mTORC2 during VSMC senescence. We found adriamycin-induced VSMC senescence was accompanied by reduced PTEN protein expression and upregulation of the mTORC2-Akt (Ser 473) pathway and that fisetin treatment reduced VSMC senescence by increasing PTEN and decreasing mTORC2 protein levels. Furthermore, PTEN played a primary role in the anti-aging effect of fisetin, and fisetin-activated PTEN directly regulated the mTORC2-Akt (Ser 473) signaling pathway, and attenuated senescence phenotypes such as senescence-associated ß-galactosidase (SA-ß-gal) and the p53-p21 signaling pathway in VSMCs. In mouse aortas, fisetin delayed aging by regulating the PTEN-mTORC2-Akt (Ser473) signaling pathway. These results suggest PTEN and mTORC2 are associated with cellular senescence in VSMCs and that the mTORC2-Akt (Ser 473) signaling pathway be considered a new target for preventing senescence-related diseases.
Assuntos
Flavonóis/farmacologia , Músculo Liso Vascular , PTEN Fosfo-Hidrolase , Animais , Senescência Celular , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Camundongos , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
This study was undertaken to investigate immunohistochemical expression of the senescence-associated secretory phenotype (SASP) in invasive breast cancer (IBC) tissues and to determine relationships between SASP positivity and tumor microenvironments and the clinicopathological characteristics of IBC. Immunohistochemistry for senescence markers, that is, high mobility group box-1 (HMGB1), p16, p15, and decoy receptor 2 (DCR2), was performed in tissue microarrays of 1140 IBC samples. Cases positive for at least one of these four markers were considered SASP-positive. Relations between SASP and tumor characteristics, including immune microenvironments (stromal tumor-infiltrating lymphocytes [sTILs] density and numbers of intraepithelial CD103-positive [iCD103 + ] lymphocytes) and clinical outcomes were retrospectively evaluated. HMGB1, p16, p15, or DCR2 was positive in 6.7%, 26.6%, 21.1%, and 26.5%, respectively, of the 1,140 cases. Six hundred and five (53.1%) cases were SASP positive, and SASP positivity was significantly associated with histologic grade 3, high-sTIL and iCD103 + lymphocyte counts, absence of ER or PR, and a high Ki-67 index. Although SASP did not predict breast cancer-specific survival (BCSS) or disease-free survival (DFS) in the entire cohort, SASP positivity in luminal A IBC was associated with poor BCSS and DFS. However, patients with SASP-positive TNBC showed better survival than those with SASP-negative TNBC. In multivariate analysis, SASP positivity was an independent prognostic factor in both luminal A IBC and TNBC, although the effect on prognosis was the opposite. In conclusion, SASP would be involved in the modulation of immune microenvironments and tumor progression in IBC, and its prognostic significance depends on molecular subtype.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Linfócitos do Interstício Tumoral/imunologia , Fenótipo Secretor Associado à Senescência , Microambiente Tumoral , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/imunologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/cirurgia , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Selenoproteins containing selenium in the form of selenocysteine are critical for bone remodeling. However, their underlying mechanism of action is not fully understood. Herein, we report the identification of selenoprotein W (SELENOW) through large-scale mRNA profiling of receptor activator of nuclear factor (NF)-κΒ ligand (RANKL)-induced osteoclast differentiation, as a protein that is downregulated via RANKL/RANK/tumour necrosis factor receptor-associated factor 6/p38 signaling. RNA-sequencing analysis revealed that SELENOW regulates osteoclastogenic genes. SELENOW overexpression enhances osteoclastogenesis in vitro via nuclear translocation of NF-κB and nuclear factor of activated T-cells cytoplasmic 1 mediated by 14-3-3γ, whereas its deficiency suppresses osteoclast formation. SELENOW-deficient and SELENOW-overexpressing mice exhibit high bone mass phenotype and osteoporosis, respectively. Ectopic SELENOW expression stimulates cell-cell fusion critical for osteoclast maturation as well as bone resorption. Thus, RANKL-dependent repression of SELENOW regulates osteoclast differentiation and blocks osteoporosis caused by overactive osteoclasts. These findings demonstrate a biological link between selenium and bone metabolism.
Assuntos
Remodelação Óssea/genética , Osteoclastos/fisiologia , Osteogênese/genética , Osteoporose/genética , Selenoproteína W/metabolismo , Proteínas 14-3-3/metabolismo , Animais , Diferenciação Celular/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Fatores de Transcrição NFATC/metabolismo , Osteoporose/patologia , Ligante RANK/metabolismo , RNA-Seq , Selenoproteína W/genética , Transdução de Sinais/fisiologia , Fator 6 Associado a Receptor de TNF/metabolismoRESUMO
Senescent cells drive atherosclerosis at all stages and contribute to cardiovascular disease. However, the markers in these senescent aortic plaques have not been well studied, creating a huge obstacle in the exploration of a precise and efficient system for atherosclerosis treatment. Recently, CD9 has been found to induce cellular senescence and aggravated atherosclerotic plaque formation in apolipoprotein E knockout (ApoE-/-) mice. In the present study, this result has been leveraged to develop CD9 antibody-modified, hyaluronic acid-coated mesoporous silica nanoparticles with a hyaluronidase-responsive drug release profile. In invitro models of senescent foamy macrophages and senescent endothelial cells stimulated with oxidized high-density-lipoprotein, the CD9 antibody-modified mesoporous silica nanoparticles exhibit high cellular uptake; reduce the reactive oxygen species level, high-density lipoprotein oxidation, and production of TNF-α and IL-6; and attenuate the senescence process, contributing to improved cell viability. In vivo experiment demonstrated that these nanoparticles can successfully target the senescent lesion areas, deliver the anti-senescence drug rosuvastatin to the senescent atherosclerotic plaques (mainly endothelial cells and macrophages), and alleviate the progression of atherosclerosis in ApoE-/- mice. By providing deep insight regarding the markers in senescent atherosclerotic plaque and developing a nano-system targeting this lesion area, the study proposes a novel and an accurate therapeutic approach for mitigating atherosclerosis through senescent cell clearance.
Assuntos
Aterosclerose , Células Endoteliais , Macrófagos , Nanopartículas , Placa Aterosclerótica , Animais , Aorta , Aterosclerose/tratamento farmacológico , Modelos Animais de Doenças , Camundongos , Camundongos Knockout para ApoE , Placa Aterosclerótica/tratamento farmacológico , Dióxido de SilícioRESUMO
CD9 is a transmembrane glycoprotein belonging to the tetraspanin family. CD9 expression has been reported to be associated with cellular signaling, cell adhesion, cell migration, and tumor related processes. The aim of this study was to examine the immunohistochemical expression of CD9 in vascular senescence and atherosclerosis. One hundred and twenty samples of normal young arteries (obtained from individuals aged 0-60 years), 40 samples of normal old arteries (obtained from individuals aged 61-80 years), and 67 samples of atherosclerotic arteries were obtained from surgically resected specimens. Tissue microarray blocks were prepared for immunohistochemical staining. Immunohistochemical staining detected CD9 expression in 10.8% (13 of 120 samples) of normal young arteries and 30.0% (12 of 40 samples) of normal old arteries. CD9 expression was absent or mildly present in the smooth muscle cells and endothelial cells of normal arteries. Normal old arteries showed significantly higher expression of CD9 than normal young arteries (P<0.01). Atherosclerotic arteries showed moderate or strong CD9 expression (65 of 67 samples, 97.0%), which was observed in the smooth muscle cells, endothelial cells, macrophages, and atheromatous plaques. CD9 was significantly expressed in the atherosclerotic arteries compared to normal young and old arteries (P<0.01). The results suggest that CD9 expression may play an important role in the vascular senescence and pathogenesis of atherosclerosis.
Assuntos
Artérias/imunologia , Aterosclerose/imunologia , Tetraspanina 29/análise , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artérias/patologia , Aterosclerose/patologia , Biomarcadores/análise , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica , Adulto JovemRESUMO
Cellular senescence is associated with inflammation and the senescence-associated secretory phenotype (SASP) of secreted proteins. Vascular smooth muscle cell (VSMC) expressing the SASP contributes to chronic vascular inflammation, loss of vascular function, and the developments of age-related diseases. Although VSMC senescence is well recognized, the mechanism of VSMC senescence and inflammation has not been established. In this study, we aimed to determine whether prednisolone (PD) attenuates adriamycin (ADR)-induced VSMC senescence and inflammation through the SIRT1-AMPK signaling pathway. We found that PD inhibited ADR-induced VSMC senescence and inflammation response by decreasing p-NF-κB expression through the SIRT1-AMPK signaling pathway. In addition, Western blotting revealed PD not only increased SIRT1 expression but also increased the phosphorylation of AMPK at Ser485 in ADR-treated VSMC. Furthermore, siRNA-mediated downregulation or pharmacological inhibitions of SIRT1 or AMPK significantly augmented ADR-induced inflammatory response and senescence in VSMC despite PD treatment. In contrast, the overexpression of SIRT1 or constitutively active AMPKα (CA-AMPKα) attenuated cellular senescence and p-NF-κB expression. Taken together, the inhibition of p-NF-κB by PD through the SIRT1 and p-AMPK (Ser485) pathway suppressed VSMC senescence and inflammation. Collectively, our results suggest that anti-aging effects of PD are caused by reduced VSMC senescence and inflammation due to reciprocal regulation of the SIRT1/p-AMPK (Ser485) signaling pathway.
Assuntos
Senescência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Prednisolona/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Regulação para Baixo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Aging is a major risk factor for hypertension and atherosclerosis, and vascular smooth muscle cell (VSMC) senescence can promote aging-related vascular diseases. Sirtuin-1 (SIRT1) and AMP-activated protein kinase (AMPK) were previously reported to modulate vascular senescence; however, its effects have not been well characterized. To determine the nature of the interaction between SIRT1 and AMPK in VSMC senescence, we investigated the effects of SRT1720 on its downstream targets of SIRT1 and the phosphorylation of AMPKα at Ser485. During Adriamycin-induced VSMC senescence, SRT1720 increased the activity of SIRT1 and AMPKα phosphorylation at Ser485 via the cAMP-protein kinase A (PKA) pathway. Telomere length and telomerase reverse transcriptase expression were increased by SIRT1 activation with SRT1720. Taken together, these data show that activation of the SIRT1/cAMP-PKA/p-AMPKα (Ser485) pathway may be an effective antisenescence mechanism for VSMCs.
Assuntos
Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Serina/antagonistas & inibidores , Sirtuína 1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Serina/metabolismoRESUMO
CD9, a 24 kDa tetraspanin membrane protein, is known to regulate cell adhesion and migration, cancer progression and metastasis, immune and allergic responses, and viral infection. CD9 is upregulated in senescent endothelial cells, neointima hyperplasia, and atherosclerotic plaques. However, its role in cellular senescence and atherosclerosis remains undefined. We investigated the potential mechanism for CD9-mediated cellular senescence and its role in atherosclerotic plaque formation. CD9 knockdown in senescent human umbilical vein endothelial cells significantly rescued senescence phenotypes, while CD9 upregulation in young cells accelerated senescence. CD9 regulated cellular senescence through a phosphatidylinositide 3 kinase-AKT-mTOR-p53 signal pathway. CD9 expression increased in arterial tissues from humans and rats with age, and in atherosclerotic plaques in humans and mice. Anti-mouse CD9 antibody noticeably prevented the formation of atherosclerotic lesions in ApoE-/- mice and Ldlr-/- mice. Furthermore, CD9 ablation in ApoE-/- mice decreased atherosclerotic lesions in aorta and aortic sinus. These results suggest that CD9 plays critical roles in endothelial cell senescence and consequently the pathogenesis of atherosclerosis, implying that CD9 is a novel target for prevention and treatment of vascular aging and atherosclerosis.
Assuntos
Senescência Celular , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Tetraspanina 29/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Bloqueadores/farmacologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Criança , Pré-Escolar , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lactente , Camundongos Knockout , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Tetraspanina 29/deficiência , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Adulto JovemRESUMO
BACKGROUND/AIMS: Idiopathic pulmonary fibrosis (IPF) is a specific form of progressive and chronic interstitial lung disease of unknown cause. IPF is characterized by excessive deposition of extracellular matrix (ECM) and destructive pathological remodeling due to epithelial-to-mesenchymal transition (EMT). Eventually, lung interstitium thickens and stiffens and breathing becomes difficult. It has been well established that the transforming growth factor-ß1 (TGF-ß1)/Smad signaling pathway plays a critical role in the pathogenesis of pulmonary fibrosis. TGF-ß1-mediated activation of mitogen activated protein kinase (MAPK) family affects Smad signaling. p90RSK is a serine/threonine kinase and is activated by the extracellular signal-regulated kinase (ERK) signaling pathway. However, the roles played by p90RSK in TGF-ß1 signaling and the pathogenesis of pulmonary fibrosis remain unknown. METHODS: We investigated whether p90RSK regulates the pathogenesis of pulmonary fibrosis using in vitro and in vivo systems and Western blotting, real-time quantitative PCR, transcriptional activity assays and immunofluorescence studies. RESULTS: Pharmacological inhibition of p90RSK by FMK or inhibition of p90RSK with adenoviral vector encoding a dominant negative form of p90RSK suppressed TGF-ß1-induced ECM accumulation and EMT in lung epithelial cells and fibroblasts. Interestingly, FMK significantly inhibited TGF-ß1-induced Smad3 nuclear translocation and smad binding element-dependent transcriptional activity, but not Smad3 phosphorylation. Furthermore, in a mouse model of bleomycin-induced lung fibrosis, FMK ameliorated pulmonary fibrosis. CONCLUSION: These findings indicate that p90RSK plays critical roles in pulmonary fibrosis, which suggests it be viewed as a novel therapeutic target for the treatment of lung fibrosis.
Assuntos
Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteína Smad3/metabolismo , Animais , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Matriz Extracelular/metabolismo , Humanos , Isoquinolinas/farmacologia , Cetonas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Piridinas/farmacologia , Pirróis/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/genética , Ativação Transcricional/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismoRESUMO
Clinical intraportal pancreatic islet infusion is popular for treating type I diabetes. However, multiple doses of islets and anti-rejection protocols are needed to compensate for early large cell losses post-infusion due to the harsh hepatic environment. Thus, extrahepatic sites are utilized to enable efficient islet engraftment and reduce islet mass. Here, we reported an effective islet revascularization protocol that was based on the co-implantation of islet/fibrin gel construct with poly(lactic-co-glycolic) acid sheet releasing NECA (5'-(N-ethylcarboxamido) adenosine; a potent agonist of adenosine) into mouse epididymal fat pad. Thin, flexible sheets (d = 4 mm) prepared by simple casting exhibited sustained NECA release for up to 21 days, which effectively improved early islet engraftment with a median diabetic reversal time of 18.5 days. Western blotting revealed the facilitative effect of NECA on VEGF expression from islets in vitro and from grafts in vivo. In addition, NECA directly promoted the angiogenic activities of islet-derived endothelial cells by enhancing their proliferation and vessel-like tube formation. As a result, neovasculatures were effectively formed in the engrafted islet vicinity, as evidenced by vasculature imaging and immunofluorescence. Taken together, we suggest NECA-releasing PLGA sheets offer a safe and effective drug delivery system that enhances islet engraftment while reducing islet mass at extrahepatic sites for clinical relevance.
Assuntos
Adenosina-5'-(N-etilcarboxamida) , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Próteses e Implantes , Animais , Células Endoteliais , Camundongos , Transplante de Órgãos , PolímerosRESUMO
Aging is one of the risk factors for the development of cardiovascular diseases. During the progression of cellular senescence, cells enter a state of irreversible growth arrest and display resistance to apoptosis. As a flavonoid, quercetin induces apoptosis in various cells. Accordingly, we investigated the relationship between quercetin-induced apoptosis and the inhibition of cellular senescence, and determined the mechanism of oxidative stress-induced vascular smooth muscle cell (VSMC) senescence. In cultured VSMCs, hydrogen peroxide (H2O2) dose-dependently induced senescence, which was associated with increased numbers of senescence-associated ß-galactosidase-positive cells, decreased expression of SMP30, and activation of p53-p21 and p16 pathways. Along with senescence, expression of the anti-apoptotic protein Bcl-2 was observed to increase and the levels of proteins related to the apoptosis pathway were observed to decrease. Quercetin induced apoptosis through the activation of AMP-activated protein kinase. This action led to the alleviation of oxidative stress-induced VSMC senescence. Furthermore, the inhibition of AMPK activation with compound C and siRNA inhibited apoptosis and aggravated VSMC senescence by reversing p53-p21 and p16 pathways. These results suggest that senescent VSMCs are resistant to apoptosis and quercetin-induced apoptosis attenuated the oxidative stress-induced senescence through activation of AMPK. Therefore, induction of apoptosis by polyphenols such as quercetin may be worthy of attention for its anti-aging effects.
RESUMO
BACKGROUND: Cuban sugarcane wax acids (SCWA) and policosanol (PCO) are mixtures of higher aliphatic acids and alcohols, respectively, purified from sugarcane wax with different chief components. Although it has been known that they have antioxidant and anti-inflammatory activities, physiological properties on molecular mechanism of SCWA have been less studied than PCO. METHODS: In this study, we compared antiatherogenic activities of SCWA and PCO via encapsulation with reconstituted high-density lipoproteins (rHDL). RESULTS: After reconstitution, SCWA-rHDL showed smaller particle size than PCO-rHDL with increase of content. PCO-rHDL or SCWA-rHDL showed distinct inhibition of glycation with similar extent in the presence of fructose. PCO-rHDL or SCWA-rHDL showed strong antioxidant activity against cupric ion-mediated oxidation of low-density lipoproteins (LDL), and inhibition of oxLDL uptake into macrophages. Although PCO-rHDL showed 1.2-fold stronger inhibition against cholesteryl ester transfer protein (CETP) activity than SCWA-rHDL, SCWA-rHDL enhanced 15% more brain cell (BV-2) growth and 23% more regeneration of tail fin in zebrafish. CONCLUSION: PCO and SCWA both enhance the beneficial functions of HDL to maximize its antioxidant, antiglycation, and antiatherosclerotic activities and the inhibition of CETP. These enhancements of HDL functionality by PCO and SCWA could exert antiaging and rejuvenation activity.
Assuntos
Ácidos/farmacologia , Anticolesterolemiantes/farmacologia , Proteínas de Transferência de Ésteres de Colesterol/antagonistas & inibidores , Álcoois Graxos/farmacologia , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saccharum/química , Ceras/química , Ácidos/isolamento & purificação , Nadadeiras de Animais/efeitos dos fármacos , Nadadeiras de Animais/crescimento & desenvolvimento , Animais , Anticolesterolemiantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Álcoois Graxos/isolamento & purificação , Humanos , Macrófagos/metabolismo , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Oxirredução , Extratos Vegetais/isolamento & purificação , Regeneração , Células THP-1 , Adulto Jovem , Peixe-Zebra/crescimento & desenvolvimentoRESUMO
Fibrosarcoma is a skin tumor that is frequently observed in humans, dogs, and cats. Despite unsightly appearance, studies on fibrosarcoma have not significantly progressed, due to a relatively mild tumor severity and a lower incidence than that of other epithelial tumors. Here, we focused on the role of a recently-found dermis zinc transporter, ZIP13, in fibrosarcoma progression. We generated two transformed cell lines from wild-type and ZIP13-KO mice-derived dermal fibroblasts by stably expressing the Simian Virus (SV) 40-T antigen. The ZIP13-/- cell line exhibited an impairment in autophagy, followed by hypersensitivity to nutrient deficiency. The autophagy impairment in the ZIP13-/- cell line was due to the low expression of LC3 gene and protein, and was restored by the DNA demethylating agent, 5-aza-2'-deoxycytidine (5-aza) treatment. Moreover, the DNA methyltransferase activity was significantly increased in the ZIP13-/- cell line, indicating the disturbance of epigenetic regulations. Autophagy inhibitors effectively inhibited the growth of fibrosarcoma with relatively minor damages to normal cells in xenograft assay. Our data show that proper control over autophagy and zinc homeostasis could allow for the development of a new therapeutic strategy to treat fibrosarcoma.
Assuntos
Autofagia , Proteínas de Transporte de Cátions/deficiência , Derme/metabolismo , Fibrossarcoma/patologia , Animais , Autofagia/efeitos dos fármacos , Azacitidina/farmacologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , DNA (Citosina-5-)-Metiltransferases/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Etilenodiaminas/farmacologia , Fibrossarcoma/genética , Humanos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Zinco/metabolismoRESUMO
Cell-based delivery platforms have received great interest in recent years and have been indicated as a promising strategy for cancer immunotherapy. Despite their wide applications in the clinical and preclinical stages, their concomitant viability and efficacy remain major issues. Herein, a strategy for harnessing regulatory T (Treg) cells is developed as an actively targeting drug-delivery system to transport drug-loaded liposomes to the desired tumor sites via conjugating liposomes on the surface of Treg cells. Under the guidance of tumor-oriented chemokines, liposome-anchored Treg cells can be leveraged to migrate and infiltrate the acidic tumor microenvironment, where pH-sensitive liposomes release the loaded cargos [comprising interleukin-2, programmed cell death ligand 1 antibody (PD-L1), and imiquimod], provoke dramatic dendritic cell maturation, block the PD-1/PD-L1 immune-checkpoint, elevate the frequency of infiltrating CD8+ effector T cells, and collectively contribute to potent inhibition of in situ and metastatic tumors. Here, the findings suggest a potential approach that offers a simple, robust, and safe insight into the tuning of Treg cells as an encouraging vector for augmenting cancer immunotherapy.
Assuntos
Lipossomos/química , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/imunologia , Animais , Quimiotaxia , Citotoxicidade Imunológica , Concentração de Íons de Hidrogênio , Imunoterapia , Neoplasias Pulmonares/secundário , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Distribuição TecidualRESUMO
Skeletal muscle atrophy reduces quality of life and increases morbidity and mortality in patients with chronic conditions. Oxidative stress is a key factor contributing to skeletal muscle atrophy by altering both protein synthesis and protein degradation pathways. Beta-lapachone (Beta-L) is known to act as a pro-oxidant in cancer cells but suppresses oxidative stress in normal cells and tissues. In the present study, we examined whether Beta-L (100â¯mg/kg body weight) prevents immobilization-induced skeletal muscle atrophy in male C57BL/6N mice. Skeletal muscle atrophy was induced by immobilization of left hindlimbs for two weeks, and right hindlimbs were used as controls. The muscle weights of gastrocnemius (0.132⯱â¯0.003â¯g vs. 0.115⯱â¯0.003â¯g in Beta-L and SLS, respectively, pâ¯<â¯0.01) and tibialis anterior (0.043⯱â¯0.001 vs. 0.027⯱â¯0.002 in Beta-L and SLS, respectively, pâ¯<â¯0.001) were significantly heavier in Beta-L-treated mice than that in SLS-treated mice in immobilization group, which was accompanied by improved skeletal muscle function as tested by treadmill exhaustion and grip strength test. Immobilization increased H2O2 levels, while Beta-L treatment normalized such levels (1.6⯱â¯0.16⯵M vs. 2.7⯱â¯0.44⯵M in Beta-L and vehicle, respectively, pâ¯<â¯0.05). Oxidative stress makers were also normalized by Beta-L treatment. Protein synthesis signaling pathways were unaltered in the case of both immobilization and Beta-L treatment. However, protein catabolic, ubiquitin-proteasomal, and autophagy-lysosomal pathways were stimulated by immobilization and were normalized by Beta-L treatment. Upregulation of transforming growth factor ß and Smad 2/3 after immobilization was significantly diminished by Beta-L treatment. These results suggest that Beta-L attenuates the loss of muscle weight and function induced by immobilization through suppression of oxidative stress.