RESUMO
Evodia rutaecarpa has been used to treat inflammatory digestive disorders in Asian countries. However, little is known about the antitumor activities of E. rutaecarpa and its bioactive constituent evodiamine (EVO). The aim of this study was to characterize the antitumor mechanisms of E. rutaecarpa and EVO in human hepatocytes. Human Chang liver cells were transfected with activator protein 1 (AP-1)-luciferase reporter gene and designated as Chang/AP-1 cells. The Chang/AP-1 cells were treated with E. rutaecarpa and its bioactive constituents, and challenged with the AP-1 stimulator 12-O-tetradecanoylphorbol-13- acetate (TPA). The present study showed that the methanol extract of E. rutaecarpa decreased the TPA-induced AP-1 transactivation in Chang/AP-1 cells, with an EC50 value of 24.72 µg/mL. EVO inhibited the TPA-induced AP-1 transactivation and colony formation, with EC50 values of 82 µM and 8.2 µM, respectively. Moreover, EVO significantly diminished the TPA-induced phosphorylation of extracellular signal-regulated kinases (ERKs). These results suggested that EVO treatment suppressed the TPA-induced AP-1 activity via the ERKs pathway. In conclusion, EVO inhibited the AP-1 activity and cellular transformation in human hepatocytes, suggesting that EVO was a potential agent for antitumor therapy.
Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Quinazolinas/farmacologia , Fator de Transcrição AP-1/metabolismo , Ativação Transcricional/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular , Evodia/química , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Humanos , Fosforilação , Extratos Vegetais/farmacologia , Acetato de Tetradecanoilforbol/efeitos adversos , TransfecçãoRESUMO
Enterotoxigenic Escherichia coli (ETEC) is responsible for millions of deaths in developing countries. Heat-labile enterotoxin (LT), the virulence factor of ETEC, induces diarrhea by initially binding to the G(M1) on the surface of intestinal epithelial cells and consequently leading to the massive loss of fluid and ions from cells. Fruit of Chaenomeles (FC), the dried fruit of Chaenomeles speciosa, has been used for diarrhea in China. However, the anti-diarrheal mechanism of FC is still unclear. In this study, we demonstrated that FC extract (FCE) inhibited the LT-induced diarrhea in mice by blocking the binding of the B subunit of LT (LTB) to G(M1). The ethyl acetate (EA) soluble fraction was the most active fraction of FC that significantly abolished the LTB and G(M1) interaction. Furthermore, the oleanolic acid, ursolic acid, and betulinic acid from EA fraction, blocked the toxin binding effects, resulting in the suppression of LT-induced diarrhea. Moreover, by docking techniques, these compounds fitted LTB well via hydrogen bonds and hydrophobic contacts with amino acid residues of LTB. In conclusion, our findings suggested that oleanolic acid, ursolic acid, and betulinic acid were the active constituents from FC and might be considered as lead therapeutic agents in the treatment of LT-induced diarrhea.
Assuntos
Toxinas Bacterianas/toxicidade , Diarreia/prevenção & controle , Enterotoxinas/toxicidade , Proteínas de Escherichia coli/toxicidade , Extratos Vegetais/farmacologia , Rosaceae/química , 1-Butanol/química , Acetatos/química , Animais , Antidiarreicos/química , Antidiarreicos/isolamento & purificação , Antidiarreicos/farmacologia , Toxinas Bacterianas/metabolismo , Diarreia/induzido quimicamente , Relação Dose-Resposta a Droga , Enterotoxinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Proteínas de Escherichia coli/metabolismo , Feminino , Frutas/química , Imunoglobulina M/análise , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Ácido Oleanólico/análise , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Triterpenos Pentacíclicos , Extratos Vegetais/química , Ligação Proteica/efeitos dos fármacos , Subunidades Proteicas/metabolismo , Triterpenos/análise , Triterpenos/química , Triterpenos/farmacologia , Ácido Betulínico , Ácido UrsólicoRESUMO
Glycyrrhizin, a major component of Glycyrrhiza uralensis (licorice) root, is a saponin and exhibits a number of pharmacological effects, including anti-inflammation, anti-ulcer, anti-allergy, and anticarcinogenesis. Activator protein I (AP-1), a nuclear transcription factor, consists of Jun/Fos heterodimers or Jun/Jun homodimers, and blocking of tumor promoter-induced AP-1 activity could inhibit induced cellular transformation. In order to elucidate the molecular mechanism of glycyrrhizin-induced anticarcinogenesis, effect of glycyrrhizin on the AP-1 activity in untreated and tumor promoter-12-O-tetradecanoylphorbol-13-acetate (TPA)-treated conditions was analyzed in this study. Glycyrrhizin induced the AP-1/TATA reporter activity in a dose-dependent fashion, which was judged by chloramphenicol acetyltransferase assay and electrophoretic mobility-shift assay. Similar results were observed in HepG2 and Vero cells, suggested that glycyrrhizin effect was cell type-independent. In addition, the cis element responsible for glycyrrhizin activity was AP-1 responsive element. Further analysis indicated that glycyrrhizin exhibited a different regulation on the AP-1 activity in untreated and TPA-treated cells. Glycyrrhizin induced the AP-1 activity in untreated cells, while it inhibited the TPA-induced AP-1 activation in TPA-treated cells. These results provide insight into the biological actions of glycyrrhizin and the molecular basis for the development of new chemoprotective agents for cancer.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Fator de Transcrição AP-1/genética , Animais , Anticarcinógenos/farmacologia , Carcinoma Hepatocelular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hepáticas , Regiões Promotoras Genéticas , Elementos de Resposta , TATA Box , Acetato de Tetradecanoilforbol/farmacologia , Fator de Transcrição AP-1/metabolismo , Transfecção , Células Tumorais Cultivadas , Células VeroRESUMO
Inflammatory bowel disease is a chronic colonic inflammation that displays symptoms like diarrhea and weight loss. Acupuncture has been widely accepted by Western countries for the treatment of pain. Here, we analyzed efficacy and mechanism of electroacupuncture (EA) on trinitrobenzene sulfonic acid- (TNBS-) induced colitis in mice. Mice were intrarectally administered with 250 mg/kg TNBS and electroacupunctured at Quze (PC3) and Neiguan (PC6) acupoints, which have been applied for gastrointestinal disorders. Gene expression profiles in colons and spleens were analyzed by microarray for the elucidation of mechanism of EA. Our data showed that EA at PC3 and PC6 improved macroscopic and microscopic features of colitis and the improvement displayed a frequency-dependent manner. Administration of TNBS upregulated the expression of most cytokine genes in colons, while EA downregulated the expression of TNBS-induced cytokine genes. Pathway analysis showed that EA significantly affected inflammatory pathways in colons and immunity-associated pathway in spleens. Immunohistochemical staining further showed that EA decreased the expression of interleukin-1 ß and nuclear factor- κ B. In conclusion, this is the first study reporting the global gene expression profiles of EA on TNBS-induced colitis. Our findings suggested that inflammatory and immunity pathways were involved in the anti-inflammatory mechanism of EA on colitis induced by TNBS.
RESUMO
Zuo-Jin-Wan (ZJW) has been used to treat hepatocellular carcinoma in Asia. This study was to determine whether ZJW and its components blocked activator protein 1 (AP-1) and nuclear factor-κB (NF-κB) activities as well as tumor promotion in hepatoblastoma HepG2 cells. ZJW and its components, Coptis chinensis and Evodia rutaecarpa, inhibited AP-1 and NF-κB activities, and suppressed anchorage-independent growth of HepG2 cells. The major alkaloidal ingredients, berberine and evodiamine, inhibited AP-1 activities and/or NF-κB activation, and further suppressed hepatocellular transformation. In conclusion, ZJW and its constituents, berberine and evodiamine, suppressed tumor promotion primarily through AP-1 and/or NF-κB pathways in HepG2 cells.