A new cyclic diarylheptanoid from the bark of Myrica rubra / 药学学报

To study the chemical constituents from the bark of Myrica rubra, fourteen compounds were isolated from the methanolic extract using various chromatographic techniques, including silica gel, Sephadex LH-20 and preparative HPLC. Their structures were identified on the basis of chemical properties and spectroscopic data, as 3, 5-dimethoxy-4-hydroxymyricanol (1), myricanol (2), myricanone (3), myricanol 11-sulfate (4), myricitrin (5), quercetin (6), quercetin-3-rhamnoside (7), tamarixol (8), uvaol (9), ursolic acid (10), taraxerol (11), myricadiol (12), β-sitosterol (13) and β-daucosterol (14). Among them, compound 1 is a new compound, named as 3, 5-dimethoxy-4-hydroxymyricanol, compounds 8, 9 were isolated from the genus Myrica for the first time.

Protect effects and the underlying mechanisms of myricitrin against vascular endothelial cells apoptosis induced by oxidative stress / 药学学报

This study is to report the study of protective effects of myricitrin against oxidative stress-induced apoptosis of vascular endothelial cells and the investigation of the possible mechanisms of action of myricitrin. The model of H2O2-induced apoptosis of vascular endothelial cells was used to determine the protective effects of myricitrin. The levels of LDH, MDA and the activities of SOD, NO were measured using the respective kits. The H2O2-induced apoptosis of vascular endothelial cells was detected using MTT reduction, TUNEL assay, JC-1 and ROS staining. The activation of Caspase-3 was also measured by fluorometry. The expression of apoptosis-related proteins was determined with Western blotting assay. Myricitrin had significant protective effects against H2O2-induced apoptosis of vascular endothelial cells in a time- and dose-dependent manner. The results show that myricitrin could attenuate H2O2-induced decrease in the activities of SOD (P < 0.01). Myricitrin could decrease the levels of LDH, MDA and increase cell viability and the mitochondrial membrane potential (P < 0.01). Myricitrin had protective effects in a dose-dependent manner between 32 micromol x L(-1) to 64 micromol x L(-1). Myricitrin pretreatment could attenuate H2O2-induced increase of p-ERK. Moreover, myricitrin pretreatment could up-regulate the expression of the anti-apoptotic protein Bcl-2, down-regulate the expression of the pro-apoptotic protein Bax, and decrease the expression of Caspase-3, 9. In conclusion, myricitrin had significant protective effects against H2O2-induced apoptosis of vascular endothelial cells. Myricitrin can enhance the activities of anti-oxidative enzymes and decrease the production of free radicals. The possible mechanisms of action of myricitrin are due to myricitrin-mediated inhibition of phosphorylation of the apoptosis signaling pathways-related kinase ERK, up-regulation of the expression of the anti-apoptotic protein, and down-regulation of the expression of the pro-apoptotic protein.

Experimental Study on Antitumor Effects of Total Glycoside of Cimicifuga dahurica Maxim / 中国中医药信息杂志

Objective To investigate the antitumor effects of total glycoside of Cimicifuga dahurica (TGCD) in vivo and in vitro, and further explore its mechanisms. Methods The anti-tumor activity in vitro was determined by MTT assay and the anti-tumor activity in vivo was evaluated using experimental mouse tumor (S180) model and human tumor (A549) xenografts in nude mice. After treatment, A549 cell apoptosis and morphologic change were evaluated by Annexin V/PI flow cytometry and HE staining. Results Inhibitory concentration 50% (IC50) of TGCD on A549, HepG2, HL60, Eca-109 and MDA-MB231 cells were 20.3, 27.1, 21.2, 23.4 and 32.7 ?g/mL respectively. Administration of TGCD (100 or 200 mg/kg) inhibited S180 solid tumor development in mice, the inhibition rates were 42.8% and 54.6% respectively. Administration of TGCD (100 or 200 mg/kg) inhibited A549 tumor growth with a T/C (mean value of treated group/mean value of control group) value of 58.1% and 52.2% respectively. In addition, increased percentage of apoptotic cells induced by TGCD in human A549 nude mice xenografts and the histopathological changes including cell shrinkage and condensation of chromosomes were observed. Conclusion TGCD has demonstrated antitumor bioactivity both in vitro and in vivo, which may be related to its effects of inducing apoptosis activity.

Studies on the Peroxide Isoenzyme and the Soluble Protein of Various Types of Tall Gastrodia(Gastrodia elata) / 中草药

By means of polyacry1amide gel slab electrophoresis,the peroxide isoenzyme and the so1uble protein ofvarious types of Gastrodia elata in different growing periods were studied. The results revealed that the appar-ent varieties of G. elata are not stable in heredity.