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Circular RNA (circRNA) is thought to mediate the occurrence and development of human cancer and usually acts as a tiny RNA (miRNA) sponge to regulate downstream gene expression. However, it is not clear whether and how circACVR2A (hsa_circ_0001073) is involved in the progression of HCC. The purpose of this study is to clarify the potential role and molecular mechanism of circACVR2A in regulating the progression of hepatocellular carcinoma cells (HCC). The abundance of related proteins in circACVR2A, microRNA (miR511-5p) and PI3K-Akt signaling pathway was determined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) or Western blotting. Cell viability, invasion and apoptosis were analyzed by CCK-8, Transwell analysis and Tunel staining, respectively. The interaction between circACVR2A and microRNA was evaluated by double luciferase reporter gene assay. The results showed that circACVR2A was highly expressed in hepatocellular carcinoma cell lines. Our in vivo and in vitro data showed that circACVR2A promoted the proliferation, migration and invasion of HCC. In terms of mechanism, we found that circACVR2A can directly interact with miR511-5p and act as a miRNA sponge to regulate the expression of related proteins in PI3K-Akt signaling pathway.In HCC, circACVR2A can mediate miR-511-5p/mRNA network to activate PI3K signal pathway. This shows that the molecular regulatory network with circACVR2A as the core is a new potential target for diagnosis and treatment of hepatocellular carcinoma.
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Carcinoma Hepatocelular , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MicroRNAs , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , RNA Circular , Transdução de Sinais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , MicroRNAs/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , RNA Circular/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Movimento Celular/genética , Animais , Linhagem Celular Tumoral , Camundongos , Apoptose/genética , Progressão da Doença , MasculinoRESUMO
BACKGROUND: Cervicovaginal microbiome plays an important role in the persistence of HPV infection and subsequent disease development. However, cervicovaginal microbiota varied cross populations with different habits and regions. Identification of population-specific biomarkers from cervicovaginal microbiota and host metabolome axis may support early detection or surveillance of HPV-induced cervical disease at all sites. Therefore, in the present study, to identify HPV-specific biomarkers, cervicovaginal secretion and serum samples from HPV-infected patients (HPV group, n = 25) and normal controls (normal group, n = 17) in Xichang, China were collected for microbiome (16S rRNA gene sequencing) and metabolome (UHPLC-MS/MS) analysis, respectively. RESULTS: The results showed that key altered metabolites of 9,10-DiHOME, α-linolenic acid, ethylparaben, glycocholic acid, pipecolic acid, and 9,12,13-trihydroxy-10(E),15(Z)-octadecadienoic acid, correlating with Sneathia (Sneathia_amnii), Lactobacillus (Lactobacillus_iners), Atopobium, Mycoplasma, and Gardnerella, may be potential biomarkers of HPV infection. CONCLUSION: The results of current study would help to reveal the association of changes in cervicovaginal microbiota and serum metabolome with HPV infections.
Assuntos
Microbiota , Infecções por Papillomavirus , Feminino , Humanos , Vagina , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Metaboloma , Microbiota/genética , Biomarcadores/metabolismoRESUMO
Macrophages, crucial components of the human immune system, can be polarized into M1/M2 phenotypes, each with distinct functions and roles. Macrophage polarization has been reported to be significantly involved in the inflammation and fibrosis observed in kidney injury. MicroRNA (miRNA), a type of short RNA lacking protein-coding function, can inhibit specific mRNA by partially binding to its target mRNA. The intricate association between miRNAs and macrophages has been attracting increasing interest in recent years. This review discusses the role of miRNAs in regulating macrophage-mediated kidney injury. It shows how miRNAs can influence macrophage polarization, thereby altering the biological function of macrophages in the kidney. Furthermore, this review highlights the significance of miRNAs derived from exosomes and extracellular vesicles as a crucial mediator in the crosstalk between macrophages and kidney cells. The potential of miRNAs as treatment applications and biomarkers for macrophage-mediated kidney injury is also discussed.
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INTRODUCTION: Liuweizhiji Gegen-Sangshen (LGS) oral liquid is a Chinese patent medicine that is widely used for the prevention and treatment of alcoholic liver disease in clinical practice. However, the chemical complexity of LGS has not yet been investigated. OBJECTIVE: The aim of this study was to rapidly identify chemical constituents of LGS and establish a quality control method based on fingerprint and quantitative analysis. METHODOLOGY: A comprehensive strategy was used by combining qualitative analysis by ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and fingerprint analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD). RESULTS: A total of 162 chemical components in LGS, including 91 flavonoids, 31 organic acids, and 20 phenolic compounds, were identified or preliminarily characterized in both positive and negative ion modes based on the UPLC-Q-TOF-MS results. Of these, 37 were confirmed with the reference standards. In fingerprint analysis, 23 peaks were chosen as common peaks and used to evaluate the similarity of different batches of LGS. Subsequently, a rapid quantification method was optimized and validated for the simultaneous determination of multiple chemical markers in LGS. The validated quantitative method was successfully used to analyze different batches of LGS samples. CONCLUSION: The proposed comprehensive strategy combining HPLC-DAD fingerprinting and multi-component quantification demonstrated satisfactory results with high efficiency, accuracy, and reliability. This can be used as a reference for the overall quality consistency evaluation of Chinese patent medicines.
Assuntos
Medicamentos de Ervas Chinesas , Controle de Qualidade , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Flavonoides/análise , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Administração Oral , Fenóis/análiseRESUMO
Efficient and mild synthetic routes for bioactive natural product derivatives are of current interest for drug discovery. Herein, on the basis of the pharmacophore hybrid strategy, we report a two-step protocol to obtain a series of structurally novel oleanolic acid (OA)-dithiocarbamate conjugates in mild conditions with high yields. Moreover, biological evaluations indicated that representative compound 3e exhibited the most potent and broad-spectrum antiproliferative effects against Panc1, A549, Hep3B, Huh-7, HT-29, and Hela cells with low cytotoxicity on normal cells. In terms of the IC50 values, these OA-dithiocarbamate conjugates were up to 30-fold more potent than the natural product OA. These compounds may be promising hit compounds for the development of novel anti-cancer drugs.
Assuntos
Antineoplásicos , Ácido Oleanólico , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células HeLa , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de CélulasRESUMO
Adipocytes express several kinds of catecholamine receptors, including adrenergic receptors, and dopamine receptors. Signaling pathways mediated by catecholamine receptors, such as ß3-adrenergic receptor pathway, can induce body energy expenditure via activating thermogenesis of adipose tissue. However, the roles of adipose dopamine receptors on adipocytes are still unclear. Here, we investigate the role of dopamine receptor D1 (DRD1) on adipocytes. To this end, we use DRD1 agonist Fenoldopam and antagonist SCH23390 to stimulate and inhibit DRD1 signaling, respectively. We found that, compared with control group mice, Fenoldopam-treated and SCH23390-treated high-fat-diet (HFD)-fed mice showed smaller and bigger white adipose tissue/adipocyte sizes, respectively. Meanwhile, activating of DRD1 signaling enhanced intracellular levels of cAMP, phosphorylation levels of protein kinase A substrates, and hormone-sensitive lipase, a key enzyme for lipolysis in mature 3T3-L1 adipocytes and white adipose tissue of HFD-fed mice. As a result, the levels of free fatty acid or glycerol were increased, indicating stimulation of lipolysis by DRD1 activation. Moreover, activating DRD1 can induce the browning of adipocytes, as indicated by enhanced phosphorylation of P38 MAP kinase, increased expression of beige cell markers (PGC-1α, UCP-1, and CD81), mitochondrion content, and expression of ß-oxidation related genes. All of these effects were reduced after treating with SCH23390 both in vitro and in HFD-fed mice. Collectively, our study indicated that DRD1 signaling stimulates lipolysis and browning of white adipocytes in vitro and in vivo. Understanding the functions of DRD1 on human adipocytes and adipose tissues will help us to design novel strategies to treat obesity.
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Adipócitos Marrons/metabolismo , Adipócitos Brancos/metabolismo , Lipólise , Receptores de Dopamina D1/metabolismo , Transdução de Sinais , Células 3T3-L1 , Animais , Tamanho Celular , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dieta Hiperlipídica , Comportamento Alimentar , Teste de Tolerância a Glucose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteína Desacopladora 1/metabolismo , Regulação para Cima/genética , Aumento de Peso/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Lung cancer is the second leading cause of cancer-related death worldwide. In recent decades, investigators have found that microRNAs, a group of non-coding RNAs, are abnormally expressed in lung cancer, and play important roles in the initiation and progression of lung cancer. These microRNAs have been used as biomarkers and potential therapeutic targets of lung cancer. Polyphenols are natural and bioactive chemicals that are synthesized by plants, and have promising anticancer effects against several kinds of cancer, including lung cancer. Recent studies identified that polyphenols exert their anticancer effects by regulating the expression levels of microRNAs in lung cancer. Targeting microRNAs using polyphenols may provide a novel strategy for the prevention and treatment of lung cancer. In this review, we reviewed the effects of polyphenols on oncogenic and tumor-suppressive microRNAs in lung cancer. We also reviewed and discussed the potential clinical application of polyphenol-regulated microRNAs in lung cancer treatment.
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Anticarcinógenos , Neoplasias Pulmonares , MicroRNAs , Anticarcinógenos/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/prevenção & controle , MicroRNAs/metabolismo , Polifenóis/farmacologia , Polifenóis/uso terapêuticoRESUMO
Dynamin-Related-Protein 1 (DRP1) critically regulates mitochondrial and peroxisomal fission in multicellular organisms. However, the impact of DRP1 on other organelles, especially its direct influence on ER functions remains largely unclear. Here, we report that DRP1 translocates to endoplasmic reticulum (ER) in response to ß-adrenergic stimulation. To further investigate the function of DRP1 on ER-lipid droplet (LD) dynamics and the metabolic subsequences, we generated an adipose tissue-specific DRP1 knockout model (Adipo-Drp1flx/flx ). We found that the LDs in adipose tissues of Adipo-Drp1flx/flx mice exhibited more unilocular morphology with larger sizes, and formed less multilocular structures upon cold exposure. Mechanistically, we discovered that abnormal LD morphology occurs because newly generated micro-LDs fail to dissociate from the ER due to DRP1 ablation. Conversely, the ER retention of LDs can be rescued by the overexpressed DRP1 in the adipocytes. The alteration of LD dynamics, combined with abnormal mitochondrial and autophagy functions in adipose tissue, ultimately lead to abnormalities in lipid metabolism in Adipo-Drp1flx/flx mice.
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Tecido Adiposo/metabolismo , Dinaminas/metabolismo , Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Células 3T3 , Adipócitos/metabolismo , Animais , Autofagia/fisiologia , Linhagem Celular , Células HEK293 , Humanos , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Proteínas Mitocondriais/metabolismoRESUMO
Gastric cancer (GC) development is a complex process displaying polytropic cell and molecular landscape within gastric tumor microenvironment (TME). Stromal cells in TME, including fibroblasts, endothelial cells, mesenchymal stem cells, and various immune cells, support tumor growth, metastasis, and recurrence, functioning as the soil for gastric tumorigenesis. Importantly, exosomes secreted by either stromal cells or tumor cells during tumor-stroma crosstalk perform as crucial transporter of agents including RNAs and proteins for cell-cell communication in GC pathogenesis. Therefore, given the distinct roles of exosomes secreted by various cell types in GC TME, increasing evidence has indicated that exosomes present as new biomarkers for GC diagnosis and prognosis and shed light on novel approaches for GC treatment.
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Exossomos , Neoplasias Gástricas , Células Estromais , Microambiente Tumoral , Animais , HumanosRESUMO
Breast cancer is the most frequently occurring cancer in women. Chemotherapy in combination with immunotherapy has been used to treat breast cancer. Atezolizumab targeting the protein programmed cell death-ligand (PD-L1) in combination with paclitaxel was recently approved by the Food and Drug Administration (FDA) for Triple-Negative Breast Cancer (TNBC), the most incurable type of breast cancer. However, the use of such drugs is restricted by genotype and is effective only for those TNBC patients expressing PD-L1. In addition, resistance to chemotherapy with drugs such as lapatinib, geftinib, and tamoxifen can develop. In this review, we address chemoresistance in breast cancer and discuss Akt as the master regulator of drug resistance and several oncogenic mechanisms in breast cancer. Akt not only directly interacts with the mitogen-activated protein (MAP) kinase signaling pathway to affect PD-L1 expression, but also has crosstalk with Notch and Wnt/ß-catenin signaling pathways involved in cell migration and breast cancer stem cell integrity. In this review, we discuss the effects of tyrosine kinase inhibitors on Akt activation as well as the mechanism of Akt signaling in drug resistance. Akt also has a crucial role in mitochondrial metabolism and migrates into mitochondria to remodel breast cancer cell metabolism while also functioning in responses to hypoxic conditions. The Akt inhibitors ipatasertib, capivasertib, uprosertib, and MK-2206 not only suppress cancer cell proliferation and metastasis, but may also inhibit cytokine regulation and PD-L1 expression. Ipatasertib and uprosertib are undergoing clinical investigation to treat TNBC. Inhibition of Akt and its regulators can be used to control breast cancer progression and also immunosuppression, while discovery of additional compounds that target Akt and its modulators could provide solutions to resistance to chemotherapy and immunotherapy.
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Antineoplásicos Imunológicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/enzimologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Feminino , Humanos , Imunoterapia , Terapia de Alvo Molecular , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Resultado do Tratamento , Hipóxia TumoralRESUMO
Natural killer (NK) cells are immune cells which are able to kill tumor and virus-infected cells and play an important role in both innate immunity and acquired immunity. Tumor immunotherapy is an emerging model of tumor treatment in the clinic. It is a re-emerging type of anticancer immunotherapy with the purpose of killing tumor cells by modulating the body's immune function and enhancing the antitumor immunity in tumor microenvironment. At present, many immune cells including lymphokine-activated killer cells, NK cells, cytokine-induced killer cells, and dendritic cells are involved in tumor immunotherapy studies. NK cells, which lyse tumor cells without prior stimulation, has become a research hotspot in cancer immunotherapy for clinical application. In this article, we discussed the surface receptors of NK cells and the anticancer function of NK cells. We also reviewed the biological characteristics and the current research status of NK cells, their clinical application in cancer immunotherapy and its future perspectives.
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Citocinas/uso terapêutico , Imunoterapia , Células Matadoras Naturais/imunologia , Neoplasias/terapia , Animais , Humanos , Neoplasias/imunologia , Receptores de Células Matadoras Naturais/imunologiaRESUMO
BACKGROUND: Fish immunity is not only affected by the innate immune pathways but is also triggered by stress. Transport and loading stress can induce oxidative stress and further activate the immune inflammatory response, which cause tissue damage and sudden death. Multiple genes take part in this process and some of these genes play a vital role in regulation of the immune inflammatory response and sudden death. Currently, the key genes regulating the immune inflammatory response and the sudden death caused by stress in Coilia nasus are unknown. RESULTS: In this study, we studied the effects of the Glo1 gene on stress, antioxidant expression, and immune-mediated apoptosis in C. nasus. The full-length gene is 4356 bp, containing six exons and five introns. Southern blotting indicated that Glo1 is a single-copy gene in the C. nasus genome. We found two single-nucleotide polymorphisms (SNPs) in the Glo1 coding region, which affect the three-dimensional structure of Glo1 protein. An association analysis results revealed that the two SNPs are associated with stress tolerance. Moreover, Glo1 mRNA and protein expression of the heterozygous genotype was significantly higher than that of the homozygous genotype. Na+ and sorbitol also significantly enhanced Glo1 mRNA and protein expression, improved the fish's antioxidant capacity, and reduced the immune inflammatory response, thus sharply reducing the mortality caused by stress. CONCLUSIONS: Glo1 plays a potential role in the stress response, antioxidant capacity, and immune-mediated apoptosis in C. nasus.
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Peixes/fisiologia , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Animais , Antioxidantes/metabolismo , Peixes/imunologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Lactoilglutationa Liase/química , Polimorfismo de Nucleotídeo Único , Conformação Proteica , Sódio/farmacologia , Sorbitol/farmacologia , Estresse FisiológicoRESUMO
DNA damage contributes to renal tubular cell death during kidney injury, but how DNA damage in tubular cells is regulated is not fully understood. Lethal (3) malignant brain tumor-like 2 (L3MBTL2), a novel polycomb group protein, has been implicated in regulating chromatin architecture. However, the biological functions of L3MBTL2 are largely undefined. Here we found that L3MBTL2 was expressed in the nuclei of renal tubular epithelial cells in mice. Ablation of L3mbtl2 in renal tubular cells resulted in increases in nuclear DNA damage, p53 activation, apoptosis, tubular injury and kidney dysfunction after cisplatin treatment or unilateral ureteral obstruction. In vitro, inhibition of L3MBTL2 sequentially promoted histone γH2AX expression, p53 activation and apoptosis in cisplatin-treated mouse proximal tubular TKPTS cells. Inhibition of p53 activity attenuated the apoptosis induced by L3mbtl2 deficiency after cisplatin treatment both in vivo and in vitro. Intriguingly, unlike other polycomb proteins, L3MBTL2 was not recruited to DNA damage sites, but instead increased nuclear chromatin density and reduced initial DNA damage load. Thus, L3MBTL2 plays a protective role in kidney injury, in part by inhibiting the DNA damage-p53-apoptosis pathway.
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Injúria Renal Aguda/metabolismo , Apoptose , Dano ao DNA , Células Epiteliais/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas Nucleares/metabolismo , Insuficiência Renal Crônica/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Células Cultivadas , Montagem e Desmontagem da Cromatina , Cisplatino , Modelos Animais de Doenças , Células Epiteliais/patologia , Histonas/metabolismo , Túbulos Renais Proximais/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Transdução de Sinais , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Obstrução Ureteral/complicaçõesRESUMO
Over the past few decades, obesity has been recognized as low-grade chronic inflammatory disease and was contributed to systemic metabolic diseases such as type 2 diabetes (T2D). Accumulating evidence indicates that adipose tissue (AT) inflammation is a key event in the pathogenesis of obesity and obesity-associated diseases. While AT-resident immune cells play important roles in maintaining AT homeostasis, obesity changes their numbers and activities, which were accompanied by the activation of inflammatory responses. Recent investigations emphasized the contributions of adaptive immune cells, especially CD4+ T cells, in controlling immune-AT crosstalk in the progression of obesity and obesity-associated disorders. In this review, we focus on the current understandings of the roles of CD4+ T cells in obesity and obesity-associated diseases, and the effects of adipocytes as antigen presenting cells on regulating CD4+ T cell activity.
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Linfócitos T CD4-Positivos/imunologia , Obesidade/imunologia , Tecido Adiposo/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Homeostase/imunologia , Humanos , Inflamação/imunologiaRESUMO
Endotrophin is a cleavage product of collagen 6 (Col6) in adipose tissue (AT). Previously, we demonstrated that endotrophin serves as a costimulator to trigger fibrosis and inflammation within the unhealthy AT milieu. However, how endotrophin affects lipid storage and breakdown in AT and how different cell types in AT respond to endotrophin stimulation remain unknown. In the current study, by using a doxycycline-inducible mouse model, we observed significant upregulation of adipogenic genes in the white AT (WAT) of endotrophin transgenic mice. We further showed that the mice exhibited inhibited lipolysis and accelerated hypertrophy and hyperplasia in WAT. To investigate the effects of endotrophin in vitro, we incubated different cell types from AT with conditioned medium from endotrophin-overexpressing 293T cells. We found that endotrophin activated multiple pathological pathways in different cell types. Particularly in 3T3-L1 adipocytes, endotrophin triggered a fibrotic program by upregulating collagen genes and promoted abnormal lipid accumulation by downregulating hormone-sensitive lipolysis gene and decreasing HSL phosphorylation levels. In macrophages isolated from WAT, endotrophin stimulated higher expression of the collagen-linking enzyme lysyl oxidase and M1 proinflammatory marker genes. In the stromal vascular fraction isolated from WAT, endotrophin induced upregulation of both profibrotic and proinflammatory genes. In conclusion, our study provides a new perspective on the effect of endotrophin in abnormal lipid accumulation and a mechanistic insight into the roles played by adipocytes and a variety of other cell types in AT in shaping the unhealthy microenvironment upon endotrophin treatment.
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Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Tecido Adiposo/citologia , Colágeno Tipo VI/genética , Fibrose/genética , Inflamação/genética , Lipólise/genética , Fragmentos de Peptídeos/genética , Células 3T3-L1 , Tecido Adiposo Branco/patologia , Animais , Colágeno/genética , Células HEK293 , Humanos , Hiperplasia , Hipertrofia , Macrófagos/imunologia , Camundongos , Camundongos Transgênicos , Fosforilação/genética , Proteína-Lisina 6-Oxidase/genética , Esterol Esterase/genética , Regulação para CimaRESUMO
Fibroblast growth factor (FGF) 19 is a member of the FGF15/19 subfamily of FGFs that includes FGF15/19, FGF21, and FGF23. FGF19 has been shown to have profound effects on liver metabolism and regeneration. FGF19 binds to FGFR4 and its coreceptor ß-Klotho to activate intracellular kinases, including Erk1/2. Studies have shown that proinflammatory cytokines such as TNFα impair FGF21 signaling in adipose cells by repressing ß-Klotho expression. However, little is known about the effects of inflammation on the FGF19 pathway in the liver. In the present study, we found that lipopolysaccharide (LPS) inhibited ß-Klotho and Fgfr4 expression in livers in mice, whereas LPS had no effects on the two FGF19 receptors in Huh-7 and HepG2 cells. Of the three inflammatory cytokines TNFα, IL-1ß, and IL-6, IL-1ß drastically inhibited ß-Klotho expression, whereas TNFα and IL-6 had no or minor effects. None of the three cytokines had any effects on FGFR4 expression. IL-1ß directly inhibited ß-Klotho transcription, and this inhibition required both the JNK and NF-κB pathways. In addition, IL-1ß inhibited FGF19-induced Erk1/2 activation and cell proliferation. These results suggest that inflammation and IL-1ß play an important role in regulating FGF19 signaling and function in the liver.
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Fatores de Crescimento de Fibroblastos/farmacologia , Hepatócitos/efeitos dos fármacos , Interleucina-1beta/farmacologia , Lipopolissacarídeos/farmacologia , Proteínas de Membrana/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento de Fibroblastos 23 , Células Hep G2 , Humanos , Interleucina-6/farmacologia , Proteínas Klotho , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/efeitos dos fármacos , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Mutations in HFE are the most common cause of hereditary hemochromatosis (HH). HFE mutations result in reduced expression of hepcidin, a hepatic hormone, which negatively regulates iron absorption from the duodenum and iron release from macrophages. However, the mechanism by which HFE regulates hepcidin expression in hepatocytes is not well understood. It is known that the bone morphogenetic protein (BMP) pathway plays a central role in controlling hepcidin expression in the liver. Here we show that HFE overexpression increased Smad1/5/8 phosphorylation and hepcidin expression, whereas inhibition of BMP signaling abolished HFE-induced hepcidin expression in Hep3B cells. HFE was found to associate with ALK3, inhibiting ALK3 ubiquitination and proteasomal degradation and increasing ALK3 protein expression and accumulation on the cell surface. The 2 HFE mutants associated with HH, HFE C282Y and HFE H63D, regulated ALK3 protein ubiquitination and trafficking differently, but both failed to increase ALK3 cell-surface expression. Deletion of Hfe in mice resulted in a decrease in hepatic ALK3 protein expression. Our results provide evidence that HFE induces hepcidin expression via the BMP pathway: HFE interacts with ALK3 to stabilize ALK3 protein and increase ALK3 expression at the cell surface.
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Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Regulação da Expressão Gênica/fisiologia , Hepcidinas/biossíntese , Antígenos de Histocompatibilidade Classe I/metabolismo , Proteínas de Membrana/metabolismo , Substituição de Aminoácidos , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Células COS , Chlorocebus aethiops , Proteína da Hemocromatose , Células Hep G2 , Hepcidinas/genética , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Metaloproteinases da Matriz Secretadas/genética , Metaloproteinases da Matriz Secretadas/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Mutação de Sentido Incorreto , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Smad/metabolismo , Ubiquitinação/fisiologiaRESUMO
Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-ß in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.
Assuntos
Apoptose , Caderinas/biossíntese , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Túbulos Renais Proximais/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Obstrução Ureteral/metabolismo , Animais , Caderinas/genética , Caspase 3/genética , Caspase 3/metabolismo , Moléculas de Adesão Celular Neuronais , Hipóxia Celular/genética , Linhagem Celular , Células Epiteliais/patologia , Proteínas Ligadas por GPI , Túbulos Renais Proximais/patologia , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Obstrução Ureteral/genética , Obstrução Ureteral/patologiaRESUMO
During inflammation, the liver becomes resistant to growth hormone (GH) actions, leading to downregulation of the GH target gene IGF-I and activation of catabolism. Proinflammatory cytokines IL-6, TNF-α, and IL-1ß are critically involved in the pathogenesis of hepatic GH resistance. However, the mechanisms used by endogenous IL-6, TNF-α, and IL-1ß to inhibit the hepatic GH-IGF-I pathway during inflammation are not fully understood. Here, we show that TNF-α and IL-1ß inhibited GH receptor (GHR) expression but had minor effects on the downstream suppressor of cytokine signaling (SOCS)3, while IL-6 induced SOCS3 expression but had no effect on GHR expression in Huh-7 cells. Consistent with the in vitro observations, neutralization of TNF-α and IL-1ß in mouse models of inflammation did not significantly alter SOCS3 expression stimulated by inflammation but restored GHR and IGF-I expression suppressed by inflammation. Neutralization of IL-6 did not alter inflammation-suppressed GHR expression but drastically reduced the inflammation-stimulated SOCS3 expression and restored IGF-I expression. Interestingly, when the GH-IGF-I pathway was turned off by maximal inhibition of GHR expression, IL-6 and SOCS3 were no longer able to regulate IGF-I expression. Taken together, our results suggest that TNF-α/IL-1ß and IL-6 use distinct mechanisms to induce hepatic GH resistance, with TNF-α and IL-1ß acting primarily on GHR and IL-6 acting primarily on SOCS3. IL-6 action may be superseded by factors such as TNF-α and IL-1ß that inhibit GHR expression.
Assuntos
Hormônio do Crescimento/metabolismo , Interleucina-1beta/farmacologia , Interleucina-6/farmacologia , Fígado/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Células Cultivadas , Humanos , Inflamação/genética , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Moléculas de Adesão de Célula Nervosa/genética , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Acacetin, one of the flavonoid compounds, is a natural product found in various plants, including Silver birch, and Damiana. Previous studies showed that acacetin has anti-cancer effects on many kinds of cancer cells, however, the role of and the mechanisms of actions of acacetin on non-small cell lung cancer (NSCLC) cells is still not fully understood. Herein, we found that, in vitro, acacetin inhibited the proliferation, invasion, and migration of NSCLC cells, A549 and H460, in a dose-dependent manner. Meanwhile, flow cytometry assay results showed that acacetin induced G2/M phase cell cycle arrest, and apoptosis of NSCLC cells. In vivo, acacetin suppressed tumor formation of A549-xenografted nude mice model with no obvious toxicities. Western blotting results showed that the protein levels of cell cycle-related proteins cyclin B1, cyclin D, and anti-apoptotic protein Bcl-2 had decreased, while the apoptosis-related protein Bak had increased both in NSCLC cells and in A549-xenografted tumor tissues. For investigating the molecular mechanism behind the biological effects of acacetin on NSCLC, we found that acacetin induced the expression levels of tumor suppressor p53 both in vitro and in vivo. MicroRNA, miR-34a, the direct target of p53, has been shown anti-NSCLC proliferation effects by suppressing the expression of its target gene programmed death ligand 1 (PD-L1). We found that acacetin upregulated the expression levels of miR-34a, and downregulated the expression levels of PD-L1 of NSCLC cells in vitro and of tumors in vivo. In vitro, knockdown p53 expression by siRNAs reversed the induction effects of acacetin on miR34a expression and abolished the inhibitory activity of acacetin on NSCLC cell proliferation. Furthermore, using agomir and antagomir to overexpress and suppress the expression miR-34a in NSCLC cells was also examined. We found that miR-34a agomir showed similar effects as acacetin on A549 cells, while miR-34a antagomir could partially or completely reverse acacetin's effects on A549 cells. In vivo, intratumor injection of miR-34a antagomir could drastically suppress the anti-tumor formation effects of acacetin in A549-xenografted nude mice. Overall, our results showed that acacetin inhibits cell proliferation and induces cell apoptosis of NSCLC cells by regulating miR-34a.