Imperatorin is responsible for the vasodilatation activity of Angelica Dahurica var. Formosana regulated by nitric oxide in an endothelium-dependent manner / 中国结合医学杂志

<p><b>OBJECTIVE</b>To demonstrate the vasodilatation activity of the coumarin-containing Angelica dahurica var. formosana and to further analyze active components in the herb extracts.</p><p><b>METHODS</b>(1) The vasodilatation effects induced by different extracts (cyclohexane, ethyl acetate, acetone, methanol, 95 % ethanol and water) of Angelica dahurica var. formosana on mouse thoracic aorta pre-contracted with phenylephrine were investigated. (2) The amount of imperatorin and isoimperatorin in each extract was measured by high-performance liquid chromatography. (3) The vasodilatation effects of imperatorin and isoimperatorin on mouse thoracic aorta were compared using the same in vitro method. (4) The vasodilatation mechanism of imperatorin in the mouse thoracic aorta pre-contracted with phenylephrine was studied using the methods of denuded endothelium, NG-nitro-L-arginine methylester (L-NAME, a nitric oxide synthase inhibitor), and propranolol.</p><p><b>RESULTS</b>(1) The cyclohexane and ethyl acetate extracts of Angelica dahurica var. formosana decreased the maximal response of phenylephrine-induced mouse thoracic aorta contraction dose-dependently, with 50% inhibiting concentration (IC(50)) values of 35.3+/-12.4 mg/L and 40.5+/-12.0 mg/L, respectively. The vasodilatation effect of imperatorin and isoimperatorin was dose-dependent. (2) The cyclohexane extract, showing the strongest vasodilatation effect, possessed the highest contents of imperatorin (4.09%) and isoimperatorin (0.27%, w/w). There was a correlation between the vasodilatation activity and the contents of imperatorin and isoimperatorin in the extracts. (3) The vasodilatation effect of imperatorin was about 4-fold stronger than that of isoimperatorin. (4) The vasodilatation effect of imperatorin was signifificantly attenuated to 24.88%+/-4.06% in the denuded endothelium group compared with the intact endothelium group. And 1 mmol/L L-NAME reduced the imperatorin-induced vasorelaxation by 32.18 %+/-11.29 %.</p><p><b>CONCLUSIONS</b>The principal effective component of Angelica dahurica var. Formosana was found to be imperatorin. Imperatorin-induced vasodilatation is at least partially regulated by nitric oxide, and has no correlation to beta-receptor.</p>

Analysis of anti-platelet aggregation components of Rhizoma Zingiberis using chicken thrombocyte extract and high performance liquid chromatography / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The conventional procedure for screening bioactive components from traditional Chinese medicine is time-consuming, expensive and low efficient. Therefore, some alternative strategies are needed urgently. A novel method for screening anti-platelet aggregation components from oleoresins was developed using chicken thrombocyte extract and high performance liquid chromatography.</p><p><b>METHODS</b>The anti-platelet aggregation components of oleoresins were combined with receptors, channels and enzymes of chicken thrombocytes under physiological environment. Unbound substances were washed away and bound compounds were eluted using specific phosphate buffered solution (PBS). Compounds released from target sites were collected and analyzed by high performance liquid chromatography and LC-MS. The activity of three compounds which were screened from this model was confirmed using platelet aggregation pharmacology in vivo.</p><p><b>RESULTS</b>There were four typical compounds that bound to the thrombocytes: 6-gingerol, 8-gingerol, 6-shogaol and 10-gingerol, and all had shown anti-platelet aggregation activities. Eight-gingerol displayed the best anti-platelet aggregation effect.</p><p><b>CONCLUSIONS</b>Chicken thrombocyte extract can be used to isolate chemicals that are ligands of the receptor or other bio-targets on the platelet. This may therefore be a simple and efficient method to screen for anti-platelet aggregation compounds from traditional Chinese medicine.</p>

Effect of gingerol on endotoxemia mouse model induced by heatstroke / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of Gingerol on endotoxemia mouse induced by heatstroke.</p><p><b>METHODS</b>Forty mice were randomly divided into five groups, the endotoxemia model group (A), the normal temperature group (B), the Gingerol treated group (C), the solvent control group (D), and the saline control group (E), 8 mice in each group. Group B to E was administered with saline, Gingerol, solvent and saline respectively. Mice in group B were placed at room temperature 25 +/- 0.5 degrees C , relative humidity 43 +/- 5 % for 2 hrs, while mice in the other groups were exposed under 35 +/- 0.5 degrees C and relative humidity 65 +/- 5 % for 2 hrs in an artificial hot-climate mimic cabin to establish heatstroke endotoxemia model. The energy metabolic level of celiomacrophage was detected with MTT; the phagocytic ability was examined with neutral red chromometry; the hepatocyte ultrastructure was observed with transmission electron microscopy, as well as the activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) in plasma was tested.</p><p><b>RESULTS</b>As compared with Group A, D and E, in Group C, energy metabolic levels of macrophage, phagocytic ability, and activity of SOD were significantly higher (P < 0.01), and the level of MDA was significantly lower respectively (P < 0.01), with the levels of SOD and MDA approaching to those in Group B (P >0.05). The pathologic changes of hepatocyte ultrastructure in group C were less than those in the other three endotoxemia groups.</p><p><b>CONCLUSION</b>Gingerol could raise the energy metabolic level of celio-macrophage to enhance its phagocytic ability, increase the activity of SOD and reduce the production of MDA in mouse with heatstroke endotoxemia, so as to alleviate the liver damage.</p>