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1.
Acta Pharmacol Sin ; 44(6): 1175-1190, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36635421

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF), an endoplasmic reticulum stress-inducible secreting protein, has evolutionarily conserved immune-regulatory function that contributes to the negative regulation of inflammation in macrophages. In this study, we investigated the profiles of MANF in the macrophages of the patients with active inflammatory bowel disease (IBD) and the mice with experimental colitis, which was induced in both myeloid cell-specific MANF knockout mice and wild-type mice by 3% dextran sodium sulfate (DSS) for 7 days. We found that MANF expression was significantly increased in intestinal macrophages from both the mice with experimental colitis and patients with active IBD. DSS-induced colitis was exacerbated in myeloid cell-specific MANF knockout mice. Injection of recombinant human MANF (rhMANF, 10 mg·kg-1·d-1, i.v.) from D4 to D6 significantly ameliorated experimental colitis in DSS-treated mice. More importantly, MANF deficiency in myeloid cells resulted in a dramatic increase in the number of Ly6ChiCX3CRint proinflammatory macrophages in colon lamina propria of DSS-treated mice, and the proinflammatory cytokines and chemokines were upregulated as well. Meanwhile, we demonstrated that MANF attenuated Th17-mediated immunopathology by inhibiting BATF2-mediated innate immune response and downregulating CXCL9, CXCL10, CXCL11 and IL-12p40; MANF functioned as a negative regulator in inflammatory macrophages via inhibiting CHOP-BATF2 signaling pathway, thereby protecting against DSS-induced mouse colitis. These results suggest that MANF ameliorates colon injury by negatively regulating inflammatory macrophage transformation, which shed light on a potential therapeutic target for IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Humanos , Camundongos , Animais , Colite/induzido quimicamente , Colite/tratamento farmacológico , Doenças Inflamatórias Intestinais/patologia , Transdução de Sinais , Macrófagos/metabolismo , Colo/metabolismo , Fatores de Crescimento Neural/genética , Camundongos Knockout , Sulfato de Dextrana/toxicidade , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Receptor 1 de Quimiocina CX3C
2.
Genes (Basel) ; 13(4)2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35456475

RESUMO

Many post-transcriptional mRNA processing steps play crucial roles in tumorigenesis and the progression of cancers, such as N6-methyladenosine (m6A) modification and alternative splicing. Upregulation of methyltransferase-like 3 (METTL3), the catalytic core of the m6A methyltransferase complex, increases m6A levels and results in significant effects on the progression of hepatocellular carcinoma (HCC). However, alternative splicing of METTL3 has not been fully investigated, and the functions of its splice variants remain unclear. Here, we analyzed both our and online transcriptomic data, obtaining 13 splice variants of METTL3 in addition to canonical full-length METTL3-A in HCC cell lines and tissues. Validated by RT-qPCR and Western blotting, we found that METTL3-D, one of the splice variants expressing a truncated METTL3 protein, exhibits higher levels than METTL3-A in normal human livers but lower levels than METTL3-A in HCC tumor tissues and cell lines. Further functional assays demonstrated that METTL3-D expression decreased cellular m6A modification, inhibited the proliferation, migration, and invasion of HCC cells, and was negatively associated with the malignancy of patient tumors, exhibiting functions opposite to those of full-length METTL3-A. This study demonstrates that the METTL3-D splice variant is a tumor suppressor that could potentially be used as a target for HCC therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenosina/genética , Adenosina/metabolismo , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Mensageiro/genética
3.
Biomed Pharmacother ; 150: 112943, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35405395

RESUMO

Acute lung injury (ALI) is an urgent respiratory disease without effective treatment. Mesencephalic astrocyte-derived neurotrophic factor (MANF)has been demonstrated to play a suppressive role in some inflammatory conditions. However, the effect of MANF on ALI has not yet been reported. In this study, we collected bronchoalveolar lavage fluid (BALF) from the patients with or without pulmonary inflammation, and used lipopolysaccharide (LPS) to induce mice ALI model. Mono-macrophage-specific MANF knockout (MKO) mice were constructed and recombinant human MANF protein was used to ALI mice. We found that the endogenous MANF protein in both human BALF and mice lung tissues was increased in inflammatory conditions. MANF level in the macrophages of inflammatory lung was higher than that in normal controls in both human and mice. MANF deficiency in macrophages induced lung inflammation and aggravated LPS-induced lung injury. MANF lowered LPS-induced lung injury, inhibited macrophage polarization to M1 functional type. Meanwhile, MANF inhibited-LPS induced activation of NF-κB signal pathway by down regulating phosphorylated p65in lung tissue and macrophages. These results indicate that MANF acts as a suppressor in ALI via negatively regulating NF-κB activation and macrophages polarization, which may be a novel potential target and shed light on ALI therapy.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Macrófagos , Fatores de Crescimento Neural , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/imunologia , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Modelos Animais de Doenças , Humanos , Lipopolissacarídeos/farmacologia , Pulmão , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/imunologia , Fatores de Crescimento Neural/metabolismo
4.
Acta Pharmacol Sin ; 41(3): 404-414, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31700088

RESUMO

Xanthatin is a natural sesquiterpene lactone purified from Xanthium strumarium L., which has shown prominent antitumor activity against a variety of cancer cells. In the current study, we investigated the effect of xanthatin on the growth of glioma cells in vitro and in vivo, and elucidated the underlying mechanisms. In both rat glioma C6 and human glioma U251 cell lines, xanthatin (1-15 µM) dose-dependently inhibited cell viability without apparent effect on the cell cycle. Furthermore, xanthatin treatment dose-dependently induced glioma cell apoptosis. In nude mice bearing C6 glioma tumor xenografts, administration of xanthatin (10, 20, 40 mg·kg-1·d-1, ip, for 2 weeks) dose-dependently inhibited the tumor growth, but did not affect the body weight. More importantly, xanthatin treatment markedly increased the expression levels of the endoplasmic reticulum (ER) stress-related markers in both the glioma cell lines as well as in C6 xenografts, including glucose-regulated protein 78, C/EBP-homologous protein (CHOP), activating factor 4, activating transcription factor 6, spliced X-box binding protein-1, phosphorylated protein kinase R-like endoplasmic reticulum kinase, and phosphorylated eukaryotic initiation factor 2a. Pretreatment of C6 glioma cells with the ER stress inhibitor 4-phenylbutyric acid (4-PBA, 7 mM) or knockdown of CHOP using small interfering RNA significantly attenuated xanthatin-induced cell apoptosis and increase of proapoptotic caspase-3. These results demonstrate that xanthatin induces glioma cell apoptosis and inhibits tumor growth via activating the ER stress-related unfolded protein response pathway involving CHOP induction. Xanthatin may serve as a promising agent in the treatment of human glioma.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Furanos/farmacologia , Glioma/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Relação Dose-Resposta a Droga , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Furanos/química , Furanos/isolamento & purificação , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Ratos , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Xanthium/química
5.
Pathol Res Pract ; 215(9): 152523, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300294

RESUMO

Mammary carcinoma (MC) is one of most common malignancy in women, and ring finger protein 2 (RNF2) possesses various roles in vast human tumors. In MC tissues as well as in cell lines RNF2 exhibited high expression, had significant association with tumor size, lymph node status, TNM stage, patients' poor survival, and promoted cell proliferation, colony formation, cell migration and invasion of MC cell lines which was mediated by downregulation of E-cadherin protein. These data reveal that RNF2 protein plays a vital role in the development of MC and may be a potential therapy target of MC.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Transição Epitelial-Mesenquimal/fisiologia , Complexo Repressor Polycomb 1/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Carcinoma/metabolismo , Carcinoma/mortalidade , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia
6.
Neurochem Res ; 44(4): 959-967, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30694428

RESUMO

Iron overload is a common pathophysiological state underlying many diseases that has a detrimental influence on cells. The protective effects of Dexmedetomidine (Dex), a high selective alpha-2-adrenoceptor agonist, have been revealed through many experimental models, whereas no study reports its effects on an iron overload model. To elucidate these effects, we used FeCl2 with or without Dex to treat SH-SY5Y cells for 24 h and then detected indicators of oxidative stress, inflammation and apoptosis and investigated possible mechanisms further. After treatment with FeCl2 for 24 h, cell viability decreased in a dose dependent manner, and Dex promoted cell survival in FeCl2 incubation, also in a dose-dependent manner. Compared with the FeCl2 group, 20 µM Dex significantly attenuated ROS accumulation, reduced pro-inflammatory cytokine expression, and inhibited apoptosis. Furthermore, 20 µM concentration of Dex remarkably downregulated the expression of pro-apoptotic protein and activation of caspase 3 while increasing anti-apoptotic protein expression. Additionally, Dex also effectively suppressed the expression of NF-κB and its activation. In conclusion, Dex exerted anti-oxidative stress, anti-inflammation, and anti-apoptosis effects on FeCl2-treated SH-SY5Y cells, possibly by inhibiting NF-κB signaling pathway.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Cloretos/toxicidade , Dexmedetomidina/farmacologia , Compostos Férricos/toxicidade , Sobrecarga de Ferro/metabolismo , NF-kappa B/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Humanos , Sobrecarga de Ferro/prevenção & controle , NF-kappa B/antagonistas & inibidores , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
7.
Eur J Pharmacol ; 843: 1-11, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30389633

RESUMO

Hepatocellular carcinoma (HCC) has high incidence and mortality in patients with chronic liver diseases worldwide. However, there are limited chemotherapeutic agents for HCC in clinic. Xanthatin, a natural sesquiterpene lactone, has significant antitumor activity against a variety of cancers, but little is known about its effects on HCC and the underlying mechanism. Here, we evaluated the antitumor effects of xanthatin on human hepatoma cells. We found that xanthatin caused morphological changes and reduced cell viability in three HCC cell lines in concentration- and time-dependent manners. Xanthatin at 10 µM significantly arrested cell cycle at the G2/M checkpoint, and at 40 µM significantly arrested cell cycle at the S phase in hepatoma cells. Additionally, xanthatin induced apoptosis associated with activation of caspase-3 in hepatoma cells, but did not apparently induce apoptosis in human normal LO2 hepatocytes. We also demonstrated that the three primary signaling pathways of unfolded protein response (UPR) were activated by xanthatin to different extents. Notably, the PERK/eIF-2α/ATF4 axis was most significantly activated by xanthatin. More importantly, both xanthatin and tunicamycin, an endoplasmic reticulum stress (ERS) inducing compound, increased the levels of CHOP and cleaved-caspase-3 in HepG2 cells, but their effects were significantly abolished by siRNA-mediated knockdown of CHOP. Further experiments validated that xanthatin more potently activated ATF4 by promoting its nuclear translocation in hepatoma cells. Taken together, we discovered that xanthatin induced apoptosis in human hepatoma cells by activating ERS. Our current data revealed a novel mechanism for xanthatin as a promising anti-tumor candidate for HCC therapy.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Furanos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
8.
Phytother Res ; 33(1): 149-158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30346082

RESUMO

To investigate the suppressive effects of xanthatin on glioma growth in a nude mouse xenograft model and rat orthotopic implantation model using magnetic resonance imaging (MRI) to dynamically monitor the antitumour growth and antiangiogenesis effects of xanthatin. The nude mouse xenograft tumour model and rat orthotopic implantation model were established to observe the antitumour effects of xanthatin in vivo. In the rat orthotopic implanted tumour model, MRI scanning was used to dynamically monitor the antitumour growth effect and evaluate the antiangiogenesis effect of xanthatin. We found that xanthatin at a dose of 0.4 mg/10 g dramatically decreased the growth of xenograft tumours in nude mice. The antiangiogenesis effect of xanthatin C6 glioma was evaluated by dynamic contrast-enhanced (DCE) MRI via comparison of the volume transfer constant (Ktrans ) value, a parameter that reflects vessel permeability. We found that xanthatin at the doses of 8 and 16 mg/kg significantly decreased the Ktrans value, which suggests that xanthatin has antiangiogenesis effects. These data demonstrate the suppressive effects of xanthatin on C6 glioma occur via antiangiogenesis. Meanwhile, this study also provides evidence for the application of quantitative parameters of DCE-MRI for dynamically evaluating the growth and angiogenesis of intracranial tumours and for experimental and clinical research.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Meios de Contraste/uso terapêutico , Furanos/uso terapêutico , Glioma/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Animais , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/patologia , Modelos Animais de Doenças , Furanos/química , Furanos/farmacologia , Glioma/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica , Ratos
9.
Mol Med Rep ; 18(6): 5765-5774, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30365109

RESUMO

Mesencephalic astrocyte­derived neurotrophic factor (MANF) is an endoplasmic reticulum stress­inducible protein, which has been suggested to be upregulated in inflammatory diseases; however, how inflammation regulates its transcription remains unclear. Activator protein­1 (AP­1), which is a transcription factor complex composed of c­Fos and c­Jun, is activated during the inflammatory process. The present study aimed to investigate whether the AP­1 complex regulates MANF transcription. The results of a luciferase reporter assay revealed that one of three putative AP­1 binding sites in the MANF promoter region is essential for enhancement of MANF transcription. Mechanistically, AP­1 was revealed to directly bind to the promoter region of the MANF gene by chromatin immunoprecipitation assay. Furthermore, MANF was strongly expressed in the liver tissues of patients with hepatitis B virus (HBV) infection, compared with in normal liver tissues from patients with hepatic hemangioma. Furthermore, c­Fos and c­Jun were also upregulated in the nuclei of hepatocytes from patients with HBV infection. In mice treated with carbon tetrachloride, the expression patterns of MANF, c­Fos and c­Jun were similar to those in patients with HBV. These results suggested that the AP­1 complex may be a novel regulator of MANF transcription, which may be involved in liver inflammation and fibrosis.


Assuntos
Regulação da Expressão Gênica , Fatores de Crescimento Neural/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Imuno-Histoquímica , Hepatopatias/etiologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Ligação Proteica
10.
World Neurosurg ; 117: e117-e129, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29883817

RESUMO

BACKGROUND: Our previous studies have shown that mesencephalic astrocyte-derived neurotrophic factor (MANF) provides a neuroprotective effect against ischemia/reperfusion injury and is also involved in inflammatory disease models. This study investigates the potential role and mechanism of MANF in acute brain damage after traumatic brain injury (TBI). METHODS: The model of TBI was induced by Feeney free falling methods with male Sprague-Dawley rats. The expression of MANF, 24 hours after TBI, was detected by the immunohistochemistry, immunofluorescence, Western blot, and reverse transcription polymerase chain reaction techniques. After treatment with recombinant human MANF after TBI, assessment was conducted 24 hours later for brain water content, cerebral edema volume in magnetic resonance imaging, neurobehavioral testing, and Evans blue extravasation. Moreover, by the techniques of Western blot and reverse transcription polymerase chain reaction, the expression of inflammatory cytokines (interleukin 1ß and tumor necrosis factor α) and P65 was also analyzed to explore the underlying protective mechanism of MANF. RESULTS: At 24 hours after TBI, we found that endogenous MANF was widely expressed in the rat's brain tissues and different types of cells. Treatment with a high dose of recombinant human MANF (20 µg/20 µL) significantly increased the modified Garcia score, and reduced brain water content as well as cerebral edema volume on magnetic resonance imaging. Furthermore, MANF alleviated not only the permeability of the blood-brain barrier (BBB) but also the expressions of interleukin 1ß and tumor necrosis factor α messenger RNA and protein. Besides, the activation of P65 was also inhibited. CONCLUSIONS: These results suggest that MANF provides a neuroprotective effect against acute brain injury after TBI, via attenuating blood-brain barrier disruption and intracranial neuroinflammation; the inhibition of the NF-κB signaling pathway might be a potential mechanism.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas Traumáticas/prevenção & controle , Fatores de Crescimento Neural/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Masculino , Doenças do Sistema Nervoso/etiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia
11.
RSC Adv ; 8(71): 40554-40563, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-35557926

RESUMO

The facile fabrication of multifunctional nanocomposites (Fe3O4/HBC@F127) consisting of superparamagnetic Fe3O4 nanoparticles and fluorescent organic hexa-peri-hexabenzocoronene (HBC) molecules incorporated in block copolymer diacylphospholipid-polyethyleneglycol F127 have been demonstrated for dual mode imaging (fluorescent/MR) and drug delivery. The obtained nanocomposites were water-dispersible, stable and biocompatible, as confirmed by dynamic light scattering (DLS) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Relativity measurements showed a T 2 relaxivity (r 2) of 214.61 mM-1 s-1, which may be used as T 2-weighted MR imaging agents. In vitro imaging studies indicated that the nanocomposites had good MR and fluorescence imaging effects with low cytotoxicity. Besides, the developed nanocomposites could also be applied as drug delivery vehicles. Doxorubicin (DOX) loaded Fe3O4/HBC@F127 nanocomposites significantly inhibited the growth of human hepatoma cells (HepG2). These findings suggested that the facile synthesized multifunctional nanocomposites may be used as a platform for dual mode imaging (both MR and fluorescence) and drug delivery.

12.
Mater Sci Eng C Mater Biol Appl ; 77: 904-911, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28532109

RESUMO

Targeting delivery of drugs in a specific manner represents a potential powerful technology in gliomas. Herein, we prepared a multifunctional targeted delivery system based on graphene oxide (GO) that contains a molecular bio-targeting ligand and superparamagnetic iron oxide nanoparticles on the surface of GO for magnetic targeting. Superparamagnetic Fe3O4 nanoparticles was loaded on the surface of GO via chemical precipitation method to form GO@Fe3O4 nanocomposites. Lactoferrin (Lf), an iron-transporting serum glycoprotein that binds to receptors overexpressed at the surface of glioma cells and vascular endothelial cell of the blood brain barrier, was chosen as the targeted ligand to construct the targeted delivery system Lf@GO@Fe3O4 through EDC/NHS chemistry. With the confirmation of TEM, DLS and VSM, the resulting Lf@GO@Fe3O4 had a size distribution of 200-1000nm and exhibited a superparamagnetic behavior. The nano delivery system had a high loading capacity and exhibited a pH-dependent release behavior. Compared with free DOX and DOX@GO@Fe3O4, Lf@GO@Fe3O4@DOX displayed greater intracellular delivery efficiency and stronger cytotoxicity against C6 glioma cells. The results demonstrated the potential utility of Lf conjugated GO@Fe3O4 nanocomposites for therapeutic application in the treatment of gliomas.


Assuntos
Nanocompostos , Linhagem Celular Tumoral , Doxorrubicina , Compostos Férricos , Glioma , Grafite , Humanos , Lactoferrina , Óxidos
13.
Inflamm Res ; 63(5): 335-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24468888

RESUMO

OBJECTIVE: To explore the characteristic expression of endoplasmic reticulum (ER) stress protein in antigen-induced arthritis models and the role of ER stress in arthritis. METHODS: Effective animal models of rheumatoid arthritis in rabbits and rats were induced by methylated bovine serum albumin and Freund's complete adjuvant. Pathological changes were assessed by magnetic resonance imaging and histological analysis. The expression and localization of ER stress proteins in synovium and peritoneal macrophages (PMΦ) were analyzed by double immunofluorescence staining. RT-PCR was performed to detect mRNA expression of ER stress-related genes. Tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß) levels in synoviocytes were measured by RT-PCR and radioimmunoassay. RESULTS: We found that the ER stress marker BiP was highly up-regulated in arthritis synovium and extensively expressed in fibroblast-like synoviocytes (FLS) and macrophage-like synoviocytes (MLS). The expression of the pro-apoptotic factor CHOP/GADD153 was slightly elevated in inflammatory synovium and mainly localized in FLS, but insignificant in MLS. Unexpectedly, increased expression of CHOP was observed in PMΦ in arthritis rats. Likewise, cleaved caspase-3 was rarely expressed in MLS. In addition, induction of ER stress by tunicamycin resulted in significantly increased expression of pro-inflammatory molecules such as IL-1ß and TNF-α in cultured inflammatory FLS. CONCLUSION: Differential activation of the ER stress proteins in synovium MLS may contribute to the resistance of synoviocytes to ER stress-induced apoptosis. Furthermore, ER stress is a potential mediator of arthritis inflammation.


Assuntos
Apoptose , Artrite Experimental/patologia , Estresse do Retículo Endoplasmático , Macrófagos/fisiologia , Membrana Sinovial/citologia , Actinas/análise , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Caspase 3/metabolismo , Células Cultivadas , Feminino , Interleucina-1beta/genética , Ativação de Macrófagos , Imageamento por Ressonância Magnética , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley , Fator de Transcrição CHOP/análise , Fator de Necrose Tumoral alfa/genética
14.
Mol Cell Biochem ; 385(1-2): 179-90, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24068329

RESUMO

Live ischemia-reperfusion injury is associated with endoplasmic reticulum (ER) stress-induced apoptosis. Activation of peroxisome proliferator-activated receptor-α (PPARα) may inhibit hepatocyte apoptosis induced by oxidative stress and protect against liver injury. This study aimed to investigate the effects of PPARα activation, through a specific agonist, on ER stress-induced apoptosis in human liver hepatocellular carcinoma (HepG2) cells. HepG2 cells were challenged with H2O2 and treated with WY14643, a selective PPARα agonist, in the presence or absence of the PPARα antagonist of MK886. Cell viable assay (MTT) and immunostaining were used to evaluate cell viability. The level of apoptotic cell death was quantified through Annexin V/PI staining. Alanine aminotransferase, asparatate aminotransferase, and malondialdehyde levels were measured to determine the presence of cellular injury and oxidative stress. RT-PCR and Western blot analysis were used to detect mRNA and protein expression of PPARα, BiP, and CHOP. Immunofluorescence was utilized to determine the intracellular localization of CHOP. H2O2 and MK886 both reduced the viability of HepG2 cells, increased oxidative stress and apoptosis, up-regulated the BiP and CHOP expression, and induced CHOP translocation from the cytoplasm to the nucleus. Compared with cells treated with H2O2 alone, pre-administration of WY14643 increased cell viability, attenuated apoptosis, improved cell function, down-regulated BiP and CHOP expression and inhibited CHOP translocation. The effects of WY14643 were completely abolished using the MK886 antagonist. PPARα activation protects against H2O2-induced HepG2 cell apoptosis. The underlying mechanisms may be associated with its activation to suppress excessive ER stress.


Assuntos
Apoptose , Citoproteção , Estresse do Retículo Endoplasmático , PPAR alfa/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular , Citoproteção/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Modelos Biológicos , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
15.
J Cereb Blood Flow Metab ; 30(1): 79-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19773801

RESUMO

Cerebral ischemia-induced accumulation of unfolded proteins in vulnerable neurons triggers endoplasmic reticulum (ER) stress. Arginine-rich, mutated in early stage tumors (ARMET) is an ER stress-inducible protein and upregulated in the early stage of cerebral ischemia. The purposes of this study were to investigate the characteristics and implications of ARMET expression induced by focal cerebral ischemia. Focal cerebral ischemia in rats was induced by right middle cerebral artery occlusion with a suture; ischemic lesions were assessed by magnetic resonance imaging and histology; neuronal apoptosis was determined by TUNEL staining; the expressions of proteins were measured by immunohistochemistry, immunofluorescent labeling, and Western blotting. ARMET was found to be extensively upregulated in ischemic regions in a time-dependent manner. The expression of ARMET was neuronal in all examined structures in response to the ischemic insult. We also found that ARMET expression is earlier and more sensitive to ischemic stimulation than C/EBP homologous protein (CHOP). ER stress agent tunicamycin induced ARMET and CHOP expressions in the primary cultured neurons. Treatment with recombinant human ARMET promoted neuron proliferation and prevented from neuron apoptosis induced by tunicamycin. These results suggest that cerebral ischemia-induced ARMET expression may be protective to the neurons.


Assuntos
Isquemia Encefálica/genética , Neurônios/patologia , Proteínas/metabolismo , Proteínas/fisiologia , Animais , Western Blotting , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Células Cultivadas , Corantes , Retículo Endoplasmático/patologia , Retículo Endoplasmático/ultraestrutura , Feminino , Imunofluorescência , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/patologia , Imageamento por Ressonância Magnética , Masculino , Fatores de Crescimento Neural , Gravidez , Proteínas/genética , Ratos , Ratos Sprague-Dawley , Sais de Tetrazólio
16.
Chin Med J (Engl) ; 122(14): 1650-4, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19719966

RESUMO

BACKGROUND: Type 2 cytokine interleukin (IL)-13 and its decoy receptor, IL-13 receptor (R) alpha2 appear to play a major role in tissue fibrosis of schistosomiasis and asthma. IL-13 is a key regulator of the extracellular matrix (ECM). It is known to signal to cells by binding to the IL-13Ralpha1, which then heterodimerizes with IL-4Ralpha. In contrast, IL-13Ralpha2 binds IL-13 with high affinity but does not signal. IL-13Ralpha2 is known to down-regulate granulomatous inflammation and prolong host survival in Schistosoma mansoni (S. mansoni) infection, but little is known about the location and expression level of IL-13Ralpha2 in the context of S. japonicum infection. METHODS: We established S. japonicum-infected mouse models. Kinetic serum levels of IL-13Ralpha2 were examined with ELISA. IL-13Ralpha2 mRNA and protein of liver tissues were determined by PCR and immunoblotting analysis, respectively. Detection of IL-13Ralpha2 expression and location in macrophages was performed by TaqMan PCR and fluorescent immunocytochemistry technique, respectively. RESULTS: A marked elevation of mRNA and protein expression of IL-13Ralpha2 was observed in mice during S. japonicum infection. An enhanced expression of IL-13Ralpha2 was further demonstrated in primary macrophages of murine schistosomiasis. CONCLUSIONS: IL-13Ralpha2 in macrophages may be a critical contributor to pathogenesis of schistosomiasis. The data highlight the potential importance of cell signaling and antifibrotic gene therapeutics in T helper 2 cell (Th2)-mediated diseases.


Assuntos
Subunidade alfa2 de Receptor de Interleucina-13/metabolismo , Macrófagos/imunologia , Schistosoma japonicum/patogenicidade , Esquistossomose Japônica/imunologia , Animais , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esquistossomose Japônica/microbiologia
17.
Zhonghua Bing Li Xue Za Zhi ; 37(2): 109-13, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18681322

RESUMO

OBJECTIVE: To investigate the expression of a novel metastasis-inducing protein human anterior gradient-2 (AGR2) in breast cancer and its clinical and prognostic significance. METHODS: AGR2 expression was assessed in 160 cases of breast cancer and 20 cases of benign breast diseases by immunohistochemistry using tissue chip technology. In addition the expression of ERa, PR and c-erbB-2 in breast cancer was also evaluated. Follow-up information of 5-year duration was available in 127 patients with breast cancer. Kaplan-Meier analysis and COX regression model were used to analyze the correlation between AGR2 expression and the follow-up clinical data. RESULTS: The expression of AGR2 was significantly higher in breast cancers than that in benign diseases (68.3% vs. 25.0% , P < 0.01). There was a negative correlation between AGR2 expression and the histological grade of breast cancer (P <0.05) , whereas positive correlations was found between the expression of AGR2 and ERalpha (P <0.05), and between the expression of AGR2 and PR (P <0.01). In the subgroup of ERalpha-positive breast cancer, Logistic regression model demonstrated AGR2 and TNM stage were important factors affecting lymph node metastasis (both P < 0.01). Kaplan-Meier analysis demonstrated that a positive expression of AGR2 was associated with poor overall survival and relapse-free survival (both P <0.01). Moreover, COX regression model confirmed the expression of AGR2 as an independent prognostic factor among patients with ERa-positive breast cancer (P <0.01). CONCLUSIONS: The abnormal expression of AGR2 may play a role in the pathogenesis and progression of breast cancer. The metastasis-inducing capability of AGR2 may be partly regulated through the ER pathway. Therefore, AGR2 may be a useful molecular marker for prognostication for patient with hormone-responsive breast cancer.


Assuntos
Proteína BRCA2/metabolismo , Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Metástase Neoplásica/diagnóstico , Proteínas/metabolismo , Receptor ErbB-2/metabolismo , Antineoplásicos Hormonais/análise , Proteína BRCA2/genética , Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Mucoproteínas , Estadiamento de Neoplasias , Proteínas Oncogênicas , Prognóstico , Proteínas/genética , Receptor ErbB-2/análise
18.
Chin Med J (Engl) ; 121(7): 602-7, 2008 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-18466679

RESUMO

BACKGROUND: Lumiracoxib is a highly selective cyclooxygenase-2 (COX-2) inhibitor with antiinflammatory, analgesic and antipyretic activities comparable with class specific drugs, but with much improved gastrointestinal safety. No studies have examined lumiracoxib for antitumorigenic activity on human nonsmall cell lung cancer cell lines in vitro or its possible molecular mechanisms. METHODS: The antiproliferative effect of lumiracoxib alone or combined with docetaxol on A549 and NCI-H460 lines was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Drug-drug interactions were analyzed using the coefficient of drug interaction (CDI) to characterize the interactions as synergism, additivity or antagonism. Morphological changes were observed by acridine orange fluorescent staining. Extent of apoptosis was determined by flow cytometry. RESULTS: Lumiracoxib (15 - 240 micromol/L) has an inhibitory effect on the proliferation of A549 and NCI-H460 cell lines in concentration- and time-dependent manners with the IC50 values of 2597 micromol/L and 833 micromol/L, respectively. The synergistic effect was prominent when lumiracoxib (15 - 240 micromol/L) was combined with docetaxol (0.2 - 2 micromol/L) (CDI < 1). Fluorescent staining showed that lumiracoxib could induce apoptosis in A549 and NCI-H460 cells. Lumiracoxib treatment also caused an increase of the sub-G1 fraction in each cell line and resulted in an increase of G0/G1-phase cells and a decrease of S-phase cells. CONCLUSIONS: Lumiracoxib had antiproliferative effect on the human nonsmall cell lung cancer cell lines A549 and NCI-H460 and had a significant synergy with docetaxol, which may be related to apoptotic induction and cell cycle arrest.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Diclofenaco/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Diclofenaco/farmacologia , Docetaxel , Humanos , Neoplasias Pulmonares/patologia , Taxoides/farmacologia
19.
Eur J Pharmacol ; 584(2-3): 246-52, 2008 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-18329639

RESUMO

Paeonol, a phenolic component from the root bark of Paeonia moutan, is traditionally used as a Chinese herbal medicine to activate the blood flow and remove blood stasis. Evidence shows that paeonol have anti-tumor, anti-inflammatory, and analgesic effects; however, the underlying mechanisms remain unknown. In this study, we investigated the molecular mechanisms by which paeonol exerts the anti-tumor effects by using a murine model of hepatoma established by in vivo injection of mouse HepA-hepatoma cells. Treatment of mice with 100, 200, or 400 mg/kg/day of paeonol significantly inhibited the growth of the HepA tumor in mice, induced HepA cell apoptosis as demonstrated by light microscopy and electron microscopy analyses, decreased the expression of Bcl-2 and increased the expression of Bax in HepA tumor tissues in a dose-related manner. Administration of paeonol in vivo also elevated serum levels of IL-2 and TNF-alpha in tumor-bearing mice. Moreover, splenocytes and macrophages isolated from paeonol-treated HepA tumor-bearing mice produced higher levels of IL-2 and TNF-alpha in response to concanavalin A and lipopolysaccharide stimulation, respectively, compared to these isolated from non-treated HepA tumor-bearing mice. In vitro treatment with paeonol was able to directly stimulate IL-2 and TNF-alpha production in splenocytes and macrophages from tumor-bearing mice, respectively. In conclusion, paeonol has the anti-tumor effect against hepatoma cells, which are likely mediated via induction of tumor cell apoptosis and stimulation of IL-2 and TNF-alpha production. Paeonol could be a promising drug to treat hepatocellular carcinoma.


Assuntos
Acetofenonas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Interleucina-2/metabolismo , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Acetofenonas/uso terapêutico , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Células Cultivadas , Relação Dose-Resposta a Droga , Interleucina-2/sangue , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/patologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Baço/efeitos dos fármacos , Baço/imunologia , Fator de Necrose Tumoral alfa/sangue , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
20.
J Pineal Res ; 43(3): 232-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17803519

RESUMO

Melatonin not only plays a major role in the regulation of circadian rhythms, but is also involved in antioxidative defense and immunomodulation. Circulating melatonin levels are derived primarily from the pineal gland while other sources of melatonin have also been reported. Here, we show for the first time that astrocytes from the rat cortex and glioma C6 cell line synthesize melatonin in vitro. In addition, we show the presence of serotonin, the precursor of melatonin and the two key enzymes in the pathway of melatonin synthesis, i.e. N-acetyltransferase and hydroxyndole-O-methyltransferase in the cultured rat cortical astrocytes. Release of melatonin into the culture medium showed no diurnal changes. These point to astrocytes as a local source of melatonin in the rat brain. Its exact physiological function remains a topic for future studies.


Assuntos
Astrócitos/metabolismo , Encéfalo/metabolismo , Melatonina/biossíntese , Acetilserotonina O-Metiltransferasa/genética , Acetilserotonina O-Metiltransferasa/metabolismo , Animais , Animais Recém-Nascidos , Arilamina N-Acetiltransferase/genética , Arilamina N-Acetiltransferase/metabolismo , Células Cultivadas , Ritmo Circadiano/fisiologia , Ratos , Ratos Sprague-Dawley , Serotonina/biossíntese
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