ABSTRACT
This study is to investigate the effect of the major chemical composition in rhizome of Pterocypsela elata, lactuside B, on expression of bcl-2, bax mRNA and their protein in rats' cerebral cortex after cerebral ischemia-reperfusion injury. First, middle cerebral artery ischemia-reperfusion injury model was established, and each group was treated with the corresponding medicines. Animals were separately sacrificed at 24 h and 72 h. The brain infarct volumes were detected by TTC dye, bcl-2 and bax mRNA expression was checked by RT-PCR, and the proteins of bcl-2 and bax were explored by two-step immunohistochemistry in cerebral cortex of rats. Lactuside B can reduce brain infarct volume of cerebral cortex of rats, increase the expression of bcl-2 mRNA and decrease that of bax mRNA. Moreover, the ratio of bcl-2 to bax mRNA is higher in 12.5 and 25 mg kg(-1) dose group, respectively, which is significantly different from that of model group (P < 0.05 or P < 0.01). Generally, either 12.5 or 25 mg kg(-1) dose group is better than positive control medicine nimodipine (P < 0.05 or P < 0.01). In addition, the expression of bcl-2 and bax protein is consistent with their gene expression. Infarct volume and the ratio of bcl-2 to bax mRNA expression are significantly different (P < 0.05 or P < 0.01) between 72 h and 24 h group. The results demonstrated that lactuside B could play a good role in resisting cerebral ischemia by upregulating the expression of bcl-2 mRNA and protein and downregulating that of bax mRNA and protein.
ABSTRACT
Objective To investigate the major chemical composition in rhizome of Pterocypsela elata and explore the activity of lactuside B against brain ischemia.Methods The compounds were isolated and purified by silica gel column chromatography and elucidated by spectroscopic experiments;The model of partial brain ischemia was used to detect water content,MDA and SOD levels in brain tissue in order to observe the activity of lactuside B against brain ischemia.Results Ten compounds were obtained and established as lactuside B(1),11?,13-dihydrolactucin acetate(2),?-sitosterol(3),daucosterol(4),(24R)-5?-stigrnast-7,22(E)-dien-3?-ol(5),3,3',4-trimethoxylellagic acid(6),?-amyrin(7),oleanolic acid(8),n-hexacosanic acid(9),and stearic acid(10).Lactuside B was a key component,and it's yield was 0.15%.Contents of water and MDA level in the brain tissue were significantly decreased,and the SOD content notably increased in all groups of lactuside B.Conclusion Ten compounds are all isolated from this plant for the first time.Compound 1 is a key component which possesses obvious activity against brain ischemia.