RESUMO
AIM: The application of strychnine (S) is limited due to its toxicity; strychnine N-oxide (SNO) is a derivative of strychnine. The aim was to employ zebrafish embryos to investigate and compare the developmental toxicity induced by S and SNO. METHODS: The toxicity of S and SNO was examined through the hatching rate and survival rate. Morphological changes of the zebrafish were observed with a dissecting microscope. Apoptosis was detected through acridine orange (AO) staining and flow cytometry. Apoptotic genes were measured by RT-PCR. RESULTS: Embryo malformation was observed in the embryos exposed to S at 200 µmol·L(-1). When SNO concentration was increased to 1 mmol·L(-1), scoliolosis, and pericardial edema could be seen in some embryos. Results from fluorescence microscopy and flow cytometry analysis showed that S at 200 µmol·L(-1) induced apoptosis, whereas the apoptotic rate in the SNO-treated group (200 µmol·L(-1)) was much lower than that in the S group. RT-PCR analysis showed that p53 mRNA expression and the ratio of Bax/Bcl-2 in the S group were significantly altered compared with the control group (*P < 0.05). Moreover, Bax mRNA expression in both S and SNO group were significantly different from that in the control group (**P < 0.01). CONCLUSION: These results lead to the conclusion that SNO has significantly lower toxicity than S in zebrafish embryos.
Assuntos
Óxidos N-Cíclicos/toxicidade , Medicamentos de Ervas Chinesas/toxicidade , Estricnina/análogos & derivados , Estricnina/toxicidade , Strychnos/química , Peixe-Zebra/embriologia , Animais , Apoptose/efeitos dos fármacos , Feminino , Masculino , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2 , Strychnos/efeitos adversos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
Recently, the renal injury caused by Semen strychni and its major toxic constituents, strychnine and brucine, was reported in many clinical cases. Hence, this study was conducted to investigate the renal injury induced by Semen Strychni and the protective effects of Radix Glycyrrhizae and Rhizoma Ligustici. The protective mechanisms were related to the comparative toxicokinetics of strychnine and brucine. Serum and urine uric acid and creatinine were used as renal function markers to evaluate the condition of kidney, and renal injury was directly reflected by histopathological changes. Compared with rats in blank group and protective herb groups, rats in Semen Strychni high-dose group showed significant differences in the results of renal function markers, and various glomerular and tubular degenerations were found in the histopathological study. The decreased AUC (only strychnine) and Cmax, the increased Tmax by Radix Glycyrrhizae and the decreased T1/2 by Radix Glycyrrhizae and Rhizoma Ligustici were found in model groups. Results indicated that high dose of Semen Strychni might induce renal injury. Radix Glycyrrhizae and Rhizoma Ligustici might work together and have effects on the elimination of strychnine and brucine. The protective effects of Radix Glycyrrhizae might also be explained by the slow absorption of the alkaloids.
