RESUMEN
The inhibition of aflatoxin B1 (AFB1) metabolism by a water extract of the root of Scutellaria baicalensis and its flavonoids was examined in liver microsomes. AFB1 is known to be metabolized to aflatoxin M1 (AFM1), aflatoxin Q1 (AFQ1), and AFB1-8,9-epoxide (AFBO). The water extract potently inhibited the production of AFM1 by cytochrome P450 (CYP)1A1/2 and slightly reduced AFBO formation by CYP1A1/2, CYP2B1, CYP2C11 and CYP3A1/2 in TCDD-treated rat liver microsomes. IC50 values for AFM1 and AFBO formation were 6.8 and 122.4 microg/ml, respectively. Wogonin showed the highest inhibitory activity towards AFM1 formation among the flavonoids isolated from the extract. On the other hand, the extract had no effects on the formation of AFBO and AFQ1 in human liver microsomes, and on the activities of CYP2B1, CYP2C11 and CYP3A1/2 which were detected by hydroxylation patterns of testosterone. These results demonstrated that the extract of the root of Scutellaria baicalensis has a specific inhibitory effect on CYP1A1/2 among CYP enzymes involved in AFB1 metabolism by rat and human microsomes.
Asunto(s)
Aflatoxina B1/metabolismo , Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Lamiaceae/química , Extractos Vegetales/farmacología , Animales , Antifúngicos/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Inhibidores Enzimáticos/química , Flavonoides/química , Flavonoides/aislamiento & purificación , Humanos , Hidroxitestosteronas/metabolismo , Cetoconazol/farmacología , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Extractos Vegetales/química , Raíces de Plantas , RatasRESUMEN
A human hepatoma cell line, Hep G2 cells, is a reliable system for the study of alcohol-induced hepatotoxicity. In this study, we investigated the effect of an aqueous extract of Asparagus cochinchinensis(MERRIL) (Liliaceae) roots (ACAE) on ethanol (EtOH)-induced cytotoxicity in Hep G2 cells. ACAE (1-100 microg/ml) dose-dependently inhibited the EtOH-induced tumor necrosis factor-alpha (TNF-alpha) secretion. ACAE (1-100 microg/ml) also inhibited the EtOH and TNF-alpha-induced cytotoxicity. Furthermore, we found that ACAE inhibited the TNF-alpha-induced apoptosis of Hep G2 cells. These results suggest that ACAE may prevent the EtOH-induced cytotoxicity through inhibition of the apoptosis of Hep G2 cells.
Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Etanol/toxicidad , Liliaceae , Neoplasias Hepáticas/metabolismo , Extractos Vegetales/uso terapéutico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Carcinoma Hepatocelular/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Etanol/antagonistas & inhibidores , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Raíces de Plantas , Células Tumorales Cultivadas/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A human hepatoma cell line, Hep G2 cells are reliable for the study of alcohol-induced hepatotoxicity. In this study, we investigated the effect of an aqueous extract of Polygala tenuifolia WILLDENOW (Polygalaceae) roots (PTAE) on ethanol (EtOH)-induced cytotoxicity in Hep G2 cells. PTAE (0.01-1 microg/ml) dose-dependently inhibited the EtOH-induced interleukin-1alpha (IL-1alpha) secretion. PTAE (0.01-1 microg/ml) also inhibited the EtOH- and IL-1alpha-induced cytotoxicity. Furthermore, we found that PTAE inhibited the IL-1alpha-induced apoptosis of Hep G2 cells. These results suggest that PTAE may prevent the EtOH-induced cytotoxicity through inhibition of the apoptosis of Hep G2 cells.
Asunto(s)
Apoptosis/efectos de los fármacos , Interleucina-1/farmacología , Plantas Medicinales , Rosales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Etanol/toxicidad , Humanos , Interleucina-1/metabolismo , Hígado/citología , Hígado/efectos de los fármacos , Hígado/inmunología , Extractos Vegetales/farmacología , Proteínas Recombinantes/farmacologíaRESUMEN
The effect of aqueous extract of Siegesbeckia glabrescence (Compositae) whole plants (SGWP) on systemic or local anaphylaxis was studied. SGWP inhibited compound 48/80-induced systemic anaphylaxis 100% with a dose of 1000 mg/kg. Oral administration of SGWP (100 mg/kg) showed a marked inhibition rate in local immunoglobulin E (IgE)-mediated passive cutaneous anaphylaxis reaction. When SGWP was pretreated at concentration ranging from 0.1 to 1000 mg/kg, the serum histamine levels were reduced in a dose-dependent manner. Moreover, SGWP dose-dependently inhibited the histamine release from peritoneal mast cells by compound 48/80. These results indicate that SGWP possess strong antianaphylactic activity by inhibition of histamine release from mast cells.