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1.
Onco Targets Ther ; 13: 9559-9571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061439

RESUMO

Background: Hepatocellular carcinoma (HCC) is an aggressive form of human liver cancer and the fifth most common malignancy worldwide. Novel effective treatment strategies for HCC are urgently in clinical because of its poor response to conventional therapies. G protein-coupled receptor kinases (GRKs), including GRK2 and GRK3, are known that involves in various essential cellular processes and regulates numerous signaling pathways. However, the role of GRK2/3 in invasion and metastasis of HCC still remains unclear. Materials and Methods: Immunohistochemistry, Western blot, laser confocal microscopy and qRT-PCR were used to detect the expression of GRK2/3 and EP2 in liver tissues of HCC patients and DEN-induced HCC mice. Wound healing and transwell assay were applied to measure the migration and invasion of HCC cells after transfected with GRK2 siRNA. The downstream pathway of Akt and ERK was verified by Western blot. Results: The expression of GRK2 was significantly decreased, while GRK3 was not significantly changed in HCC tissues compared with noncancerous tissues of HCC patients. Moreover, GRK2 expression was reduced during liver tumorigenesis in diethylnitrosamine-induced liver tumor model. In addition, our in vitro study showed that GRK2 expression was gradually decreased with increasing HCC cell line metastatic potential, and GRK2 knockdown significantly promoted the migration and invasion of HCC cells. Furthermore, low GRK2 expression was associated with increased expression of EP2 receptor translocation to HCC cell membrane, and the activation of Akt pathway. Conclusion: These data suggest that GRK2 inhibits HCC metastasis and invasion may be through regulating EP2 receptor translocation, and this effect appears to be mediated by Akt pathway.

2.
Acta Pharmacol Sin ; 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116250

RESUMO

Hepatic fibrosis is a disease characterized by excessive deposition of extracellular matrix (ECM) in the liver. Activation of hepatic stellate cells (HSCs) is responsible for most of ECM production. Oxidative stress and reactive oxygen species (ROS) may be important factors leading to liver fibrosis. NADPH oxidase 4 (NOX4) is the main source of ROS in hepatic fibrosis, but the mechanism by which NOX4 regulates oxidative stress is not fully understood. ß-Arrestin2 is a multifunctional scaffold protein that regulates receptor endocytosis, signaling and trafficking. In this study, we investigated whether ß-arrestin2 regulated oxidative stress in hepatic fibrosis. Both ß-arrestin2 knockout (Arrb2 KO) mice and wild-type mice were intraperitoneally injected with carbon tetrachloride (CCl4) to induce hepatic fibrosis. Arrb2 KO mice showed significantly attenuated liver fibrosis, decreased ROS levels and NOX4 expression, and reduced collagen levels in their livers. In vitro, NOX4 knockdown significantly inhibited ROS production, and decreased expression of alpha-smooth muscle actin in angiotensin II-stimulated human HSC cell line LX-2. Through overexpression or depletion of ß-arrestin2 in LX-2 cells, we revealed that decreased ß-arrestin2 inhibited ROS levels and NOX4 expression, and reduced collagen production; it also inhibited activation of ERK and JNK signaling pathways. These results demonstrate that ß-arrestin2 deficiency protects against liver fibrosis by downregulating ROS production through NOX4. This effect appears to be mediated by ERK and JNK signaling pathways. Thus, targeted inhibition of ß-arrestin2 might reduce oxidative stress and inhibit the progression of liver fibrosis.

3.
Acta Pharmacol Sin ; 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855529

RESUMO

ß-arrestin2 (ß-arr2) is, a key protein that mediates desensitization and internalization of G protein-coupled receptors and participates in inflammatory and immune responses. Deficiency of ß-arr2 has been found to exacerbate collagen antibody-induced arthritis (CAIA) through unclear mechanisms. In this study we tried to elucidate the molecular mechanisms underlying ß-arr2 depletion-induced exacerbation of CAIA. CAIA was induced in ß-arr2-/- and wild-type (WT) mice by injection of collagen antibodies and LPS. The mice were sacrificed on d 13 after the injection, spleen, thymus and left ankle joints were collected for analysis. Arthritis index (AI) was evaluated every day or every 2 days. We showed that ß-arr2-/- mice with CAIA had a further increase in the percentage of plasma cells in spleen as compared with WT mice with CAIA, which was in accordance with elevated serum IgG1 and IgG2A expression and aggravating clinical performances, pathologic changes in joints and spleen, joint effusion, and joint blood flow. Both LPS stimulation of isolated B lymphocytes in vitro and TNP-LPS challenge in vivo led to significantly higher plasma cell formation and antibodies production in ß-arr2-/- mice as compared with WT mice. LPS treatment induced membrane distribution of toll-like receptor 4 (TLR4) on B lymphocytes, accordingly promoted the nuclear translocation of NF-κB and the transcription of Blimp1. Immunofluorescence analysis confirmed that more TLR4 colocalized with ß-arr2 in B lymphocytes in response to LPS stimulation. Depletion of ß-arr2 restrained TLR4 on B lymphocyte membrane after LPS treatment and further enhanced downstream NF-κB signaling leading to additional increment in plasma cell formation. In summary, ß-arr2 depletion exacerbates CAIA and further increases plasma cell differentiation and antibody production through inhibiting TLR4 endocytosis and aggravating NF-κB signaling.

4.
Cell Death Dis ; 11(5): 389, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439968

RESUMO

Hepatic fibrosis is a disease of the wound-healing response following chronic liver injury, and activated hepatic stellate cells (HSCs) play a crucial role in the progression of hepatic fibrosis. ß-arrestin2 functions as a multiprotein scaffold to coordinate complex signal transduction networks. Although ß-arrestin2 transduces diverse signals in cells, little is known about its involvement in the regulation of liver fibrosis. Our current study utilized a porcine serum-induced liver fibrosis model and found increased expression of ß-arrestin2 in hepatic tissues with the progression of hepatic fibrosis, which was positively correlated with collagen levels. Furthermore, changes in human fibrotic samples were also observed. We next used ß-arrestin2-/- mice to demonstrate that ß-arrestin2 deficiency ameliorates CCl4-induced liver fibrosis and decreases collagen deposition. The in vitro depletion and overexpression experiments showed that decreased ß-arrestin2 inhibited HSCs collagen production and elevated TßRIII expression, thus downregulating the TGF-ß1 pathway components Smad2, Smad3 and Akt. These findings suggest that ß-arrestin2 deficiency ameliorates liver fibrosis in mice, and ß-arrestin2 may be a potential treatment target in hepatic fibrosis.

5.
Biochem Biophys Res Commun ; 522(2): 485-491, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31780259

RESUMO

Acute liver injury can be caused by oxidative stress within a short period and is a common pathway to many liver diseases. The liver is vulnerable to reactive oxygen species (ROS) and free radical-mediated disorders. ß-arrestin2 was initially discovered to be a negative regulator of G protein-coupled receptor signaling. Recently, ß-arrestin2 has been found to act as a multifunctional adaptor protein and play new roles in regulating intracellular signaling networks. However, the role of ß-arrestin2 in the pathogenesis of acute liver injury is unclear. In this study, we hypothesize that ß-arrestin2 regulates acute liver injury via modulation of oxidative stress. ß-arrestin2 knockout mice were used to investigate the impacts of ß-arrestin2 on carbon tetrachloride (CCl4)-induced acute liver injury and oxidative stress. Results here suggested that ß-arrestin2 deficiency decreased serum activities of aminotransferase and alleviated liver injury induced by CCl4 injection as compared with wildtype mice. ß-arrestin2 knockout mice exhibited stronger tolerance in oxidative stress compared with wild-type mice, which was demonstrated by decreased ROS level and increased superoxide dismutase (SOD) and glutathione (GSH) in the liver. Furthermore, ß-arrestin2 deficiency significantly inhibited NOX4 (a major source of ROS) expression and the activation of the extracellular regulated kinase (ERK) and, c-Jun NH2-terminal kinase (JNK) pathways. These results suggest that ß-arrestin2 deficiency protects against CCl4-induced acute liver injury through attenuating oxidative damage and decreased ERK and JNK phosphorylation.


Assuntos
Fígado/lesões , Fígado/metabolismo , Substâncias Protetoras/metabolismo , beta-Arrestina 2/metabolismo , Animais , Antioxidantes/metabolismo , Tetracloreto de Carbono , Deleção de Genes , Glutationa/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Sistema de Sinalização das MAP Quinases , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , NADPH Oxidase 4/metabolismo , Especificidade de Órgãos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
6.
Onco Targets Ther ; 12: 5499-5513, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371988

RESUMO

Background: ß2-adrenoceptors (ß2-ARs) are expressed on the surface of immune cells, including tumor-associated macrophages (TAMs). Previous studies have demonstrated that the expression of ß2-ARs in hepatocellular carcinoma (HCC) is significantly increased in vitro. However, the role of ß2-AR in M2-polarized macrophages remains unclear. G protein-coupled receptor kinase 2 (GRK2) can regulate G protein-coupled receptor (GPCR). Previous studies showed that down-regulation of GRK2 in HCC contributes the HCC progression, but it still remains unclear whether the regulation of ß2-AR in M2-polarized macrophages by GRK2 can promote HCC. Purpose: The present study was designed to investigate the role of activated ß2-AR in M2-polarized macrophages in the HCC progression and GRK2 regulatory effect, as well as the underlying mechanisms involved. Results: The results demonstrated that the M2-polarized macrophages were increased with HCC progression. In vitro, the activation of ß2-AR by terbutaline in M2-polarized macrophages elevated the proliferative, migratory and invasive attributes of HCC cells. Furthermore, GRK2 down-regulation in ß2-AR activated M2-polarized macrophages activated the downstream cyclic adenosine monophosphate (cAMP)/protein kinase A/cAMP-response element binding protein and cAMP/interleukin-6/signal transducer and the activator of transcription 3 signaling pathways, contributing to the secretion of tumor-associated cytokines, and thus resulting in the promotion of malignant biological behavior in HCC cells. Conclusion: These findings suggest that the regulation of ß2-AR occurs through the silencing of GRK2 in M2-polarized macrophages, which is conducive to HCC development, through its engagement in the activation of downstream signaling.

7.
Acta Pharmacol Sin ; 39(11): 1699-1705, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29921886

RESUMO

G protein-coupled receptor kinases (GRKs) constitute seven subtypes of serine/threonine protein kinases that specifically recognize and phosphorylate agonist-activated G protein-coupled receptors (GPCRs), thereby terminating the GPCRs-mediated signal transduction pathway. Recent research shows that GRKs also interact with non-GPCRs and participate in signal transduction in non-phosphorylated manner. Besides, GRKs activity can be regulated by multiple factors. Changes in GRKs expression have featured prominently in various tumor pathologies, and they are associated with angiogenesis, proliferation, migration, and invasion of malignant tumors. As a result, GRKs have been intensively studied as potential therapeutic targets. Herein, we review evolving understanding of the function of GRKs, the regulation of GRKs activity and the role of GRKs in human malignant tumor pathophysiology.


Assuntos
Quinases de Receptores Acoplados a Proteína G/metabolismo , Neoplasias/fisiopatologia , Animais , Humanos , Transdução de Sinais/fisiologia
8.
Int J Mol Sci ; 19(5)2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29734668

RESUMO

Among a great variety of cell surface receptors, the largest superfamily is G protein-coupled receptors (GPCRs), also known as seven-transmembrane domain receptors. GPCRs can modulate diverse signal-transduction pathways through G protein-dependent or independent pathways which involve β-arrestins, G protein receptor kinases (GRKs), ion channels, or Src kinases under physiological and pathological conditions. Recent studies have revealed the crucial role of GPCRs in the tumorigenesis and the development of cancer metastasis. We will sum up the functions of GPCRs—particularly those coupled to chemokines, prostaglandin, lysophosphatidic acid, endothelin, catecholamine, and angiotensin—in the proliferation, invasion, metastasis, and angiogenesis of hepatoma cells and the development of hepatocellular carcinoma (HCC) in this review. We also highlight the potential avenues of GPCR-based therapeutics for HCC.


Assuntos
Carcinogênese/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Receptores Acoplados a Proteínas-G/genética , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Metástase Neoplásica , Transdução de Sinais/genética , beta-Arrestinas/genética
9.
Sci Rep ; 6: 35609, 2016 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-27759077

RESUMO

ß-arrestins, including ß-arrestin1 and ß-arrestin2, are multifunctional adaptor proteins. ß-arrestins have recently been found to play new roles in regulating intracellular signalling networks associated with malignant cell functions. Altered ß-arrestin expression has been reported in many cancers, but its role in hepatocellular carcinoma (HCC) is not clear. We therefore examined the roles of ß-arrestins in HCC using an animal model of progressive HCC, HCC patient samples and HCC cell lines with stepwise metastatic potential. We demonstrated that ß-arrestin2 level, but not ß-arrestin1 level, decreased in conjunction with liver tumourigenesis in a mouse diethylnitrosamine-induced liver tumour model. Furthermore, ß-arrestin2 expression was reduced in HCC tissues compared with noncancerous tissues in HCC patients. ß-arrestin2 down-regulation in HCC was significantly associated with poor patient prognoses and aggressive pathologic features. In addition, our in vitro study showed that ß-arrestin2 overexpression significantly reduced cell migration and invasion in cultured HCC cells. Furthermore, ß-arrestin2 overexpression up-regulated E-cadherin expression and inhibited vimentin expression and Akt activation. These results suggest that ß-arrestin2 down-regulation increases HCC cell migration and invasion ability. Low ß-arrestin2 expression may be indicative of a poor prognosis or early cancer recurrence in patients who have undergone surgery for HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , beta-Arrestina 2/metabolismo , Animais , Carcinogênese , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Dietilnitrosamina , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , beta-Arrestina 2/genética
10.
Int J Mol Med ; 38(3): 903-11, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27460897

RESUMO

Protein tyrosine kinases belonging to the Janus kinase (JAK) family are associated with many cytokine receptors, which, on ligand binding, regulate important cellular functions such as proliferation, apoptosis and differentiation. The protective effects of JAK inhibitors on fibrotic diseases such as myelofibrosis and bone marrow fibrosis have been demonstrated in previous studies. The JAK inhibitor SHR0302 is a synthetic molecule that potently inhibits all members of the JAK family, particularly JAK1. However, its effect on hepatic fibrosis has not been investigated to date, to the best of our knowledge. In the present study, the effects of SHR0302 on the activation, proliferation, migration and apoptosis of hepatic stellate cells (HSCs) as well as HSC collagen production were investigated. Our data demonstrated that treatment with SHR0302 (10-9-10-5 mol/l) exerted an inhibitory effect on the activation, proliferation and migration of HSCs. In addition, the expression of collagen I and collagen III were significantly decreased following treatment with SHR0302. Furthermore, SHR0302 induced the apoptosis of HSCs, which was demonstrated by Annexin V/PI staining. SHR0302 significantly increased the activation of caspase-3 and Bax in HSCs whereas it decreased the expression of Bcl-2. SHR0302 also inhibited the activation of Akt signaling pathway. The pharmacological inhibition of the JAK1/signal transducer and activator of transcription (STAT)3 pathway led to the disruption of functions essential for HSC growth. Taken together, these findings provide evidence that SHR0302 may have the potential to alleviate hepatic fibrosis by targeting HSC functions.


Assuntos
Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno/biossíntese , Células Estreladas do Fígado/efeitos dos fármacos , Janus Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Fator de Transcrição STAT3/metabolismo , Ácidos Sulfúricos/farmacologia , Animais , Western Blotting , Caspase 3/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Células Estreladas do Fígado/metabolismo , Janus Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
11.
Oncol Rep ; 35(5): 3068-74, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26936374

RESUMO

G protein-coupled receptor kinase 2 (GRK2) is a serine/threonine kinase that is involved in a variety of important signaling pathways and alternation of GRK2 protein level or activity causes diseases such as heart failure, rheumatoid arthritis, and obesity. However, the role and mechanism of GRK2 in hepatocellular carcinoma (HCC) progression is not fully investigated. In this study we found that GRK2 plays an inhibitory role in IGF1-induced HCC cell proliferation and migration. Overexpression of GRK2 causes a decrease in early growth response-1 (EGR1) expression, while knockdown of GRK2 leads to marked increase in EGR1 expression in the treatment of IGF1. Through co-immunoprecipitation and western blot assay, we confirmed that GRK2 can interact with insulin-like growth factor 1 receptor (IGF-1R) and inhibits IGF1-induced activation of IGF1R signaling pathway. Silencing EGR1 attenuates GRK2 overexpression-caused inhibition of cell proliferation, tumor colony number and migration activity, while overexpressing of EGR1 restores the anti-proliferative and migratory effect by GRK2 overexpression in HCCLM3 cells. Collectively, these results suggest that GRK2 may inhibit IGF1-induced HCC cell growth and migration through downregulation of EGR1 and indicate that enforced GRK2 may offer a potential therapeutic approach against HCC.


Assuntos
Carcinoma Hepatocelular/enzimologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Fator de Crescimento Insulin-Like I/fisiologia , Neoplasias Hepáticas/enzimologia , Carcinoma Hepatocelular/patologia , Movimento Celular , Proliferação de Células , Regulação para Baixo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Quinase 2 de Receptor Acoplado a Proteína G/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo
12.
Oncol Rep ; 35(4): 2373-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26882862

RESUMO

The transforming growth factor ß (TGF-ß) superfamily of cytokines is multifunctional and involved in the regulation of cell growth and differentiation. TGF-ß can induce an epithelial-mesenchymal transition (EMT) of both epithelial and endothelial cells. This has consequences for cancer progression in regards to both migration and invasion abilities. The type III TGF-ß receptor (TßRIII) is a ubiquitously expressed TGF-ß co-receptor which regulates TGF-ß signaling and the progression of various types of cancer. Previous studies have shown that TßRIII exhibits abnormal expression and plays an essential role in regulating cancer invasion and metastasis, while little is known in regards to its role in hepatocellular carcinoma (HCC) progression. In the present study, we designed the present research to study the role of TßRIII in the invasion and metastasis of HCC and the possible mechanisms involved. The results demonstrated decreased expression of TßRIII in HCC patient tissues and human HCC cell lines. TGF-ß1 stimulation led to the increased migratory ability and reduced expression of TßRIII in HCC cells. In addition, knockdown of TßRIII by small interfering RNA (siRNA) promoted the migration and invasion of HCC cells and induced activation of the Smad2 and Akt pathways. All the results suggest that TßRIII is a novel suppressor of HCC progression.


Assuntos
Carcinoma Hepatocelular/patologia , Regulação para Baixo , Neoplasias Hepáticas/patologia , Proteoglicanas/genética , Proteoglicanas/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteína Smad2/metabolismo
13.
Acta Pharmacol Sin ; 36(11): 1277-87, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26388156

RESUMO

ß-Arrestins and ß-arrestin2 are important adaptor proteins and signal transduction proteins that are mainly involved in the desensitization and internalization of G-protein-coupled receptors. Fibrosis is characterized by accumulation of excess extracellular matrix (ECM) molecules caused by chronic tissue injury. If highly progressive, the fibrotic process leads to organ malfunction and, eventually, death. The incurable lung fibrosis, renal fibrosis and liver fibrosis are among the most common fibrotic diseases. Recent studies show that ß-arrestins can activate signaling cascades independent of G-protein activation and scaffold many intracellular signaling networks by diverse types of signaling pathways, including the Hedgehog, Wnt, Notch and transforming growth factor-ß pathways, as well as downstream kinases such as MAPK and PI3K. These signaling pathways are involved in the pathological process of fibrosis and fibrotic diseases. This ß-arrestin-mediated regulation not only affects cell growth and apoptosis, but also the deposition of ECM, activation of inflammatory response and development of fibrotic diseases. In this review, we survey the involvement of ß-arrestins in various signaling pathways and highlight different aspects of their regulation of fibrosis. We also discuss the important roles of ß-arrestins in the process of fibrotic diseases by regulating the inflammation and deposit of ECM. It is becoming more evident that targeting ß-arrestins may offer therapeutic potential for the treatment of fibrotic diseases.


Assuntos
Arrestinas/imunologia , Doenças Cardiovasculares/patologia , Inflamação/patologia , Enteropatias/patologia , Hepatopatias/patologia , Pneumopatias/patologia , Transdução de Sinais , Animais , Arrestinas/análise , Doenças Cardiovasculares/imunologia , Sistema Cardiovascular/imunologia , Sistema Cardiovascular/patologia , Matriz Extracelular/imunologia , Matriz Extracelular/patologia , Fibrose , Humanos , Inflamação/imunologia , Enteropatias/imunologia , Intestinos/imunologia , Intestinos/patologia , Fígado/imunologia , Fígado/patologia , Hepatopatias/imunologia , Pulmão/imunologia , Pulmão/patologia , Pneumopatias/imunologia , beta-Arrestinas
14.
Pharmacol Res ; 85: 15-22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24844437

RESUMO

Transforming growth factor ß (TGF-ß) belongs to a class of pleiotropic cytokines that are involved in the processes of embryonic development, wound healing, cell proliferation, and differentiation. Moreover, TGF-ß is also regarded as a central regulator in the pathogenesis and development of various liver diseases because it contributes to almost all of the stages of disease progression. A range of liver cells are considered to secrete TGF-ß ligands and express related receptors and, consequently, play a crucial role in the progression of liver disease via different signal pathways. In this manuscript, we review the role of the TGF-ß signaling pathway in liver disease and the potential of targeting the TGF-ß signaling in the pharmacological treatment of liver diseases.


Assuntos
Hepatopatias/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Humanos , Hepatopatias/tratamento farmacológico , Receptores de Fatores de Crescimento Transformadores beta/metabolismo
15.
Int J Oncol ; 43(5): 1643-51, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24002667

RESUMO

Paeonia lactiflora and Astragalus membranaceus are two traditional Chinese medicines, which are commonly used in Chinese herb prescription to treat liver diseases. The protective effects of the extract prepared from the roots of Paeonia lactiflora and Astragalus membranaceus (PAE) on liver fibrosis have been demonstrated in previous studies. However, its effect on hepatocellular carcinoma (HCC) has not been investigated to date. In this study, the effects of PAE on the apoptosis, proliferation, migration and invasion of the human hepatoma cell lines HepG2 and SMMC-7721 were investigated. Our data demonstrated that treatment with PAE (50-200 mg/l) caused an inhibitory effect on the proliferation of the hepatoma cell lines HepG2 and SMMC-7721. Furthermore, PAE induced apoptosis of HepG2 cells and SMMC-7721 cells, which was demonstrated by PI staining. In addition, immunocytochemistry and western blotting showed that PAE significantly decreased the expression of Bcl-2, while the expression of Bax and cleaved caspase-3 in HepG2 cells and SMMC-7721 cells was significantly increased after treatment with PAE. These results clearly demonstrated that PAE induced hepatoma cell apoptosis through increasing the Bax-to-Bcl-2 ratio and upregulating the activation of caspase-3. In addition, the results of wound healing assay and Matrigel invasion assay showed that PAE displayed inhibitory activity on the migration and invasion of HCC cells. Taken together, the present data provides evidence that PAE is a potent antineoplastic drug candidate for the treatment of HCC.


Assuntos
Apoptose/efeitos dos fármacos , Astragalus propinquus/química , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Paeonia/química , Fitoterapia , Extratos Vegetais/farmacologia , Western Blotting , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Adesão Celular , Citometria de Fluxo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Células Tumorais Cultivadas , Cicatrização
16.
Pharmacol Res ; 68(1): 38-45, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23178558

RESUMO

Anti-tumour necrosis factor-α (TNF-α) drugs are approved for the treatment of rheumatoid arthritis (RA). Many studies have investigated the effect of these drugs on the T cell response; however, some clues have indicated that it may also target B cells. This study was carried out to explore the potential effects and mechanisms of etanercept, a soluble TNF-α receptor, on the function of B cells and their development into memory B cells in type II collagen (CII)-induced arthritis (CIA). Beginning on day 24 after CII immunisation, the mice were evaluated every 2-3 days to determine two clinical parameters: their arthritis global assessment and swollen joint count (SJC). The serum concentrations of IgG1, IgG2a and anti-CII antibodies and the splenic pathology and proliferation of B cells were measured. The percentage of total memory B cells in the spleen was analysed with flow cytometry. BAFFR was detected by immunohistochemistry. In CIA mice, etanercept markedly suppressed the arthritis global assessment and the SJC, reduced the production of anti-CII, IgG1 and IgG2a antibodies, and prevented spleen histopathology to varying degrees; however, it had no obvious effect on splenic B cell proliferation. Etanercept also decreased the percentage of total CD27(+) memory B cells in the spleen. Treatment with etanercept was associated with a further increase in BAFFR expression, a significant reduction in CD27 expression, and a negative correlation between the levels of BAFFR and the percentage of memory B cells. Our findings showed that increased BAFFR expression has a regulatory effect on the activation of B cells and the generation of memory B cells, which may be one of the mechanisms of the therapeutic effects of etanercept.


Assuntos
Antirreumáticos/farmacologia , Artrite Experimental/imunologia , Linfócitos B/imunologia , Imunoglobulina G/farmacologia , Animais , Antirreumáticos/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Receptor do Fator Ativador de Células B/imunologia , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo II/imunologia , Etanercepte , Imunoglobulina G/sangue , Imunoglobulina G/uso terapêutico , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos DBA , Receptores do Fator de Necrose Tumoral/uso terapêutico , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
17.
J Cell Biochem ; 114(5): 1153-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23192415

RESUMO

ß-Arrestins are multifunctional adaptor proteins. Recently, some new roles of ß-arrestins in regulating intracellular signaling networks have been discovered, which regulate cell growth, proliferation, and apoptosis. Though, the role of ß-arrestins expression in the pathology of hepatic fibrosis remains unclear. In this study, the possible relationship between the expression of ß-arrestins with the experimental hepatic fibrosis and the proliferation of hepatic stellate cells (HSCs) were investigated. Porcine serum induced liver fibrosis was established in this study. At five time points, the dynamic expression of ß-arrestin1, ß-arrestin2, and α-smooth muscle actin (α-SMA) in rat liver tissues, was measured by immunohistochemical staining, double immunofluorescent staining, and Western blotting. This study showed that aggravation of hepatic fibrosis with gradually increasing expression of ß-arrestin2 in the hepatic tissues, but not ß-arrestin1. Further, as hepatic fibrosis worsens, ß-arrestin2-expressing activated HSCs accounts for an increasingly larger percentage of all activated HSCs. And the expression of ß-arrestin2 had a significant positive correlation with the expression of α-SMA, an activated HSCs marker. In vitro studies, the dynamic expression of ß-arrestin1 and ß-arrestin2 in platelet derived growth factor-BB (PDGF-BB) stimulated HSCs was assessed by Western blotting. The expression of ß-arrestin2 was remarkably increased in PDGF-BB stimulated HSCs. Furthermore, the small interfering RNA (siRNA) technique was used to explore the effect of ß-arrestins on the proliferation of HSCs and the activation of ERK1/2. Transfection of siRNA targeting ß-arrestin2 mRNA (siß-arrestin2) into HSCs led to a 68% and 70% reduction of ß-arrestin2 mRNA and protein expression, respectively. siß-arrestin2 abolished the effect of PDGF-BB on the proliferation of HSCs. In addition, siß-arrestin2 exerted the inhibition of the activation of ERK1/2 in HSCs. The present study provided strong evidence for the participation of the ß-arrestin2 in the pathogenesis of hepatic fibrosis. The ß-arrestin2 depletion diminishes HSCs ERK1/2 signaling and proliferation stimulated by PDGF-BB. Selective targeting of ß-arrestin2 inhibitors to HSCs might present as a novel strategy for the treatment of hepatic fibrosis.


Assuntos
Arrestinas/metabolismo , Células Estreladas do Fígado/enzimologia , Células Estreladas do Fígado/patologia , Sistema de Sinalização das MAP Quinases , Actinas/metabolismo , Animais , Arrestinas/antagonistas & inibidores , Becaplermina , Western Blotting , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Células Estreladas do Fígado/efeitos dos fármacos , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Proteínas Proto-Oncogênicas c-sis/farmacologia , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Wistar , Sus scrofa , Fatores de Tempo , beta-Arrestinas
18.
Planta Med ; 78(7): 665-71, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22411721

RESUMO

Paeoniflorin (Pae) is a monoterpene glucoside and the main component of the total glucosides of paeony (TGP) extracted from the roots of Paeonia lactiflora. Its anti-inflammatory effect is associated with regulating G-protein-coupled receptors (GPCRs) signaling. The aim of this study was to explore the expression change of G-protein-coupled receptor kinase 2 (GRK2) in fibroblast-like synoviocytes (FLS) and the effect of Pae. Pae was obtained and purified from the roots of Paeonia lactiflora. We investigated the expression of GRK2 in synovium during the inflammatory process and assessed the effects of a specific GRK2 inhibitor and Pae on proliferation, cAMP level, and protein kinase A (PKA) activity of FLS in vitro. Additionally, the effect of Pae on GRK2 expression in FLS was detected in vitro. Expression of GRK2 in synovium from CIA rats increased during the inflammatory process. The specific GRK2 inhibitor suppressed proliferation and increased the cAMP level as well as PKA activity of FLS, and Pae had the same effects. Furthermore, Pae decreased GRK2 expression in FLS in vitro. Our results indicate that a chronic inflammatory process in CIA induces upregulation of GRK2 expression in FLS, and Pae can reverse this change, which might be one of the important mechanisms for Pae regulating GPCRs signaling and suppressing the proliferation of FLS in CIA.


Assuntos
Artrite Experimental/tratamento farmacológico , Benzoatos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Quinase 2 de Receptor Acoplado a Proteína G/antagonistas & inibidores , Glucosídeos/farmacologia , Fitoterapia , Membrana Sinovial/enzimologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Proliferação de Células/efeitos dos fármacos , Doença Crônica , Colágeno , Inibidores Enzimáticos/metabolismo , Fibroblastos/enzimologia , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Humanos , Masculino , Monoterpenos , Paeonia/química , Raízes de Plantas/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos
19.
Int Immunopharmacol ; 12(4): 701-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22333895

RESUMO

The aim of this study was to explore the expression and function of ß-arrestin 2 in human fibroblast-like synoviocytes (FLS) stimulated by IL-1ß and the effect of paeoniflorin (Pae). We isolated and cultured human FLS, which were stimulated by IL-1ß. The FLS proliferations were detected by [3H] thymidine incorporation. The level of cAMP stimulated by IL-1ß on different times was investigated by radioimmunoassay, and the activity of PKA was measured by luminescent kinase assay. The expression of ß-arrestin 2 was measured by western blot. We found that the human FLS proliferation increased apparently in 24 h, and the activities of PKA and cAMP accumulation increased significantly in 6 h after stimulated by IL-1ß, while cAMP accumulation and the activities of PKA decreased especially in 24 h when the expression of ß-arrestin 2 increased significantly. Decreased cAMP accumulation and the increased expression of ß-arrestin 2 may reveal a positive correlation with the FLS proliferation. Pae (10(-5), 10(-6), 10-7 mol•L(-1)) in vitro could suppress the FLS proliferation and the high expression of ß-arrestin 2. The expression of ß-arrestin 2 may have a positive correlation with the human FLS proliferation, while the activities of PKA and cAMP accumulation have a negative correlation with the proliferation. The increased ß-arrestin 2 may down-regulate cAMP-PKA signaling pathway and promote FLS proliferation. Pae may suppress the expression of ß-arrestin 2 and up-regulate cAMP-PKA signaling, which may be one of the mechanisms for the effects of Pae on inhibiting human FLS proliferation.


Assuntos
Arrestinas/metabolismo , Benzoatos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Glucosídeos/farmacologia , Interleucina-1beta/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Monoterpenos , Paeonia , Membrana Sinovial/citologia , Membrana Sinovial/metabolismo , beta-Arrestina 2 , beta-Arrestinas
20.
Int J Mol Med ; 29(3): 491-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22109673

RESUMO

Paeonia lactiflora and Astragalus membranaceus are two popular traditional Chinese medicines, commonly used in Chinese herb prescription to treat liver disease. The extract prepared from the roots of Paeonia lactiflora and Astragalus membranaceus (PAE) demonstrated better hepatoprotective activity than the herbs used individually as shown in our previous studies. This study was carried out to investigate the effects of PAE on liver fibrosis induced by porcine serum (PS) in rats and to explore its possible mechanisms. Liver fibrosis was induced in male Wistar rats by injection with PS intraperitoneally. The rats were randomly divided into a normal control group, a liver fibrosis model group and a PAE (40, 80, 160 mg•kg-1) treated group. After a 16-week treatment, PAE-treated rats showed significantly reduced liver damage and symptoms of liver fibrosis upon pathological examination. Administration of PAE significantly decreased serum HA, PC III levels, and content of hydroxyproline in the liver tissue of fibrotic rats. It also restored the decrease in SOD and GSH-Px activities and inhibited the formation of lipid peroxidative products during PS treatment. In vitro, PAE also significantly decreased [3H]-thymidine incorporation in hepatic stellate cells (HSCs) stimulated with platelet-derived growth factor-B subunit homodimer (PDGF-BB). Moreover, PAE significantly decreased the expression of PDGF receptor beta (PDGFR-ß) and p-ERK1/2, p-p38, p-JNK. The results showed that PAE displays antifibrotic effects in rats induced by PS, the mechanism by which might be associated with its ability to scavenge free radicals, decreasing the expression of PDGFR-ß, inhibition of HSC proliferation and MAPK activation. These findings indicate that PAE is a potential agent for the prevention of liver fibrosis.


Assuntos
Astragalus propinquus/química , Medicamentos de Ervas Chinesas/farmacologia , Cirrose Hepática Experimental/metabolismo , Paeonia/química , Extratos Vegetais/farmacologia , Animais , Becaplermina , Biomarcadores/sangue , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hidroxiprolina/análise , Metabolismo dos Lipídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/tratamento farmacológico , Testes de Função Hepática , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxirredutases/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-sis/farmacologia , Ratos , Ratos Wistar , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos
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