RESUMO
Brazilein is reported to have immunosuppressive effect on cardiovascular and cerebral-vascular diseases. The essential roles of innate immunity in cerebral ischemia are increasingly identified, but no studies concerning the influence of brazilein on the innate immunity receptors have been reported. The present study was designed to investigate the regulation of NOD2 (Nucleotide-binding oligomerization domain-containing protein 2) by brazilein for its protection of neuron in cerebral ischemia in vivo and oxygen-glucose deprivation in vitro. The results showed that brazilein could reverse the elevated expression of NOD2 and TNFα (tumor necrosis factor alpha) elicited by cerebral ischemia and reperfusion. This reduction could also be detected in normal mice and C17.2 cells, indicating that this suppressive effect of brazilein was correlated with NOD2. The results from GFP reporter plasmid assay suggested brazilein inhibited NOD2 gene transcription. In conclusion, brazilein could attenuate NOD2 and TNFα expression in cerebral ischemia and NOD2 may be one possible target of brazilein for its immune suppressive effect in neuro-inflammation.
Assuntos
Benzopiranos/administração & dosagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/imunologia , Medicamentos de Ervas Chinesas/administração & dosagem , Indenos/administração & dosagem , Neurônios/efeitos dos fármacos , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Células Cultivadas , Glucose/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurônios/imunologia , Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Brazilein is an active small molecular compound extracted from Caesalpinia sappan L. with favorable pharmacological properties on immune system, cardiovascular system, and nervous system. C. sappan has been used as a traditional medicine in China for hundreds of years for various diseases. However, the general reproductive toxicity of brazilein is still unknown. The purpose of the present study was to thoroughly evaluate the general reproductive toxicity of brazilein in ICR mice to support the future drug development and modernization of this potent traditional Chinese medicine. The results showed that, although no apparent toxicity on the reproducibility of the male was observed, brazilein might cause considerable risks to the fetuses and females as indicated by the ratios of dead fetuses and reabsorptions. In conclusion, our results from the present study provided some useful insights about the safety profile of brazilein, suggesting that brazilein should be used with caution in pregnant women.
Assuntos
Benzopiranos/toxicidade , Caesalpinia/toxicidade , Medicamentos de Ervas Chinesas/toxicidade , Indenos/toxicidade , Reprodução/efeitos dos fármacos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , GravidezRESUMO
Brazilein, a natural small molecule, shows a variety of pharmacological activities, especially on nervous system and immune system. As a potential multifunctional drug, we studied the distribution and the transport behavior and metabolic behavior of brazilein in vivo and in vitro. Brazilein was found to be able to distribute in the mouse brain and transport into neural cells. A metabolite was found in the brain and in the cells. Positive and negative mode-MS/MS and Q-TOF were used to identify the metabolite. MS/MS fragmentation mechanisms showed the methylation occurred at the 10-hydroxyl of brazilein (10-O-methylbrazilein). Further, catechol-O- methyltransferase (COMT) was confirmed as a crucial enzyme correlated with the methylated metabolite generation by molecular docking and pharmacological experiment.
Assuntos
Benzopiranos/metabolismo , Indenos/metabolismo , Neurônios/metabolismo , Animais , Benzopiranos/administração & dosagem , Benzopiranos/química , Benzopiranos/farmacologia , Transporte Biológico/efeitos dos fármacos , Encéfalo/metabolismo , Catecol O-Metiltransferase/química , Catecol O-Metiltransferase/metabolismo , Morte Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Indenos/administração & dosagem , Indenos/química , Indenos/farmacologia , Masculino , Metilação/efeitos dos fármacos , Camundongos Endogâmicos ICR , Neurônios/efeitos dos fármacos , Células PC12 , Ratos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Temperatura , Raios UltravioletaRESUMO
Brazilein (6a,7-dihydro-3,6a,10-trihydroxy-benz[b]indeno[1,2-d]pyran-9(6H)-one) is a compound obtained in a large amount from Caesalpinia sappan ethanol extracts with a high purity of about 98%. In isolated cardiac tissues, we found that brazilein exhibited a positive inotropic action in a concentration-dependent manner with little effect on heart rate and coronary perfusion. To study its possible mode of action, isolated rat hearts were treated with propranolol. This treatment did not alter the cardiotonic effect of brazilein, suggesting that this effect does not involve stimulation of beta-adrenoceptors. On the other hand, an analysis of the interaction between Na(+),K(+)-ATPase and brazilein was carried out. Albino guinea pig erythrocytes (mainly alpha1-Na(+),K(+)-ATPase isoforms) enriched with Na(+),K(+)-ATPase isoforms were utilized to compare the inhibition promoted by brazilein with that of classical inhibitors such as the cardiac glycoside deslanoside. Analysis of inhibition curves revealed that unlike deslanoside, brazilein had a relatively low affinity for erythrocyte isoforms and failed to completely inhibit the Na(+),K(+)-ATPase activity. The extent of the maximum inhibition rate was about 50%. The inhibitory effect of brazilein was not antagonized by 10 mmol/l K(+), as observed with deslanoside. Electrocardiogram research in vivo showed that brazilein did not induce the ventricular arrhythmias observed with deslanoside, suggesting that brazilein might have a less adverse effect and higher therapeutic index than cardiac glycosides. In light of all the above-mentioned observations, it can be concluded that brazilein, a molecule with a non-steroidal skeleton, produced its positive inotropic effect through inhibiting Na(+),K(+)-ATPase and could thus serve as a structural paradigm to develop new inotropic drugs.