A new bibenzyl compound from Dendrobium nobile / 药学学报

In this study, seven bibenzyl compounds were isolated from the stem of Dendrobium nobile by silica gel, MCI column chromatographic and preparative HPLC technology. By using spectroscopic techniques including NMR and MS, these compounds were identified as 4, α-dihydroxy-3, 5, 3'-trimethoxybibenzyl (1), 4, 5-dihydroxy-3, 3', α-trimethoxybibenzyl (2), 4, 4'-dihydroxy-3, 5, 3'-trimethoxybibenzyl (3), 4, 5-dihydroxy-3, 3'-dimethoxybibenzyl (4), 4, 3'-dihydroxy-3, 5-dimethoxybibenzyl (5), 5, 4'-dihydroxy-3, 3'-dimethoxybibenzyl (6) and 5, 3'-dihydroxy-3-methoxybibenzyl (7). Compound 1 is a new compound and compound 4 was isolated from this plant for the first time.

Advance in studies on hepatoprotective effect of Salvia miltiorrhiza and its main components / 中国中药杂志

Dried roots and rhizomes of Salvia miltiorrhiza (Danshen) are among the most commonly used traditional Chinese medicines in clinic. The material basis for its efficacy mainly includes hydrophobic tanshinones and hydrophilic salvianolic acids. The traditional effects of Danshen are "removing stasis and relieving pain, activating blood to promote menstruation, clearing heart fire and tranquilization". According to modern pharmacological studies, Danshen and its main components have cardiovascular and cerebrovascular protective effect. Recent studies showed that Danshen and its main components also demonstrated protective effects on liver injury models induced by carbon tetrachloride, D-galactosamine, acetaminophen and alcohol. In this paper, the hepatoprotective effect and mechanism of Danshen were summarized and studied.

Distinct effect of Wansheng Huafeng Dan containing ardisia crenata on renal transporters, mercury accumulation and Kim-1 expression from mercuric chloride / 中国中药杂志

To study the effect of Wansheng Huafeng Dan (WSHFD) and mercuric chloride on renal mercury (Hg) extraction transporters (Oat1, Oct2), renal mercury excretion transporters (Mrp4, Mate2K), renal mercury accumulation and kidney injury molecule-1 (Kim-1). The ancient prescription of WSHFD containing 10-fold Hg caused much lower renal mercury accumulation and renal toxicity than HgCl2 in rats, with less effect on renal transporters than HgCl2. The above indicators had no significant difference in WSHFDO, WSHFD2 and WSHFD3 groups, indicating no effect of WSHFD with reduced or no cinnabar.

Design, synthesis and vasorelaxant activity of R, S-1-(substituted phenyl)-4-3-(naphtha-1-yl-oxy)-2-hydroxypropyl-piperazine derivatives / 药学学报

According to the results of activity-structure relationship (SAR) studies of alpha1-adrenoceptor antagonists hydantoin-phenylpiperazine and benzimidazo-arypiperazine derivatves, to design and synthesize a series of novel phenylpiperazine alpha1-adrenoceptor antagonists with more potent vasorelaxant activity, active metabolites of naftopidil were used as lead compounds. Ten novel R,S-1-substituted phenyl-4-[3-(naphthal-yl-oxy)-2-hydroxy propyl]-piperazine were designed and synthesized, their vasorelaxant activity was evaluated by calculating inhibition rate of phenylephrine-induced vasocontration of rabbit artery trips. Five compounds exhibited vasorelaxant activity, and compound 16 showed significant vasorelaxant activity in vitro. At 0.01 and 1 micromol x L(-1), its inhibition rates were 7.03% and 22.72%, respectively. This compound possessed ideal vasorelaxant activity in vitro, and would be selected for further anti-hypertension evaluation in vivo. Moreover, by analyzing the primary activity and structure relationship of these compounds, it could be concluded that the SAR results of the reported phenylpiperazine alpha1-adrenoceptor antagonists could be used for reference in designing novel derivatives of naftopidil with optimal pharmacological properties.

Protective effect of Ginkgo biloba leaf extract on learning and memory deficit induced by aluminum in model rats / 中国结合医学杂志

<p><b>OBJECTIVE</b>To examine the protective effect of Ginkgo biloba leaf extract (GbE) on learning and memory deficit induced by aluminum chloride (AlCl(3)), and explore its mechanisms.</p><p><b>METHODS</b>The rat models with learning and memory deficit were induced by administering via gastrogavage and drinking of AlCl(3) solution. And the model rats were treated with GbE at the dose of 50, 100, 200 mg/kg every day for 2 months accompanied with drinking of AlCl(3) solution, respectively. Their abilities of spatial learning and memory were tested by Morris water maze, and the acetylcholinesterase (AChE) activity in serum was assayed with chemical method, the AChE expression in hippocampus was observed by immunohistochemistry assay, and then quantitative analysis was done by BI 2000 image analysis system.</p><p><b>RESULTS</b>Learning and memory deficit of rats could be induced by AlCl(3) solution (P < 0.01), and AChE expressions in rats hippocampus were increased (P < 0.01); GbE ameliorated learning and memory deficit and reduced AChE expression in rats hippocampus in a dose-dependent manner, while GbE significantly increased serum AChE activity at the dose of 200 mg/kg each day (P < 0.05).</p><p><b>CONCLUSION</b>GbE can ameliorate learning and memory deficit induced by AlCl(3), which may be due to its inhibition of the AChE expression in hippocampus.</p>

Effects of protopine on intracellular calcium and the PKC activity of rat aorta smooth muscle / 生理学报

We have previously shown that the vasodilator effect of protopine (Pro) on rabbit aorta is related to the elevations of cAMP and cGMP. In the present study, the vasodilator mechanisms of Pro were further explored by recording the isotonic contraction of the rat aortic strips, detecting directly the intracellular free Ca(2+) concentration ([Ca(2+)](i)) with Fura-2/AM loaded vascular smooth muscle cells (VSMCs) of rat aorta, and determining the activity of protein kinase C (PKC) in rat aortic tissue with radioactive isotope gamma-32P -ATP-catalyzing assay. By recording the aortic strips contraction induced by noradrenaline (NA) and high potassium (K(+)), Pro shifted nonparallelly the concentration-response curves of NA and high K(+) to right, in which the maximal response was depressed in the presence of Pro (30 and 100 micromol/L), and the values of pD'(2) were 3.70-/+0.25 and 3.97-/+0.15 for NA and high K(+), respectively. In the Fura-2/AM loaded VSMCs, Pro (50 and 100 micromol/L) could not produce any significant change on the resting [Ca(2+)](i), but significantly decreased the [Ca(2+)](i) elevated by NA and high K(+). Pro (30 and 100 micromol/L) had no significant effect on the activity of the cytosolic and membrane PKC in the aortic strips inpretreated by NA. However, in the aortic strips pretreated by NA, the activity of membrane PKC was significantly increased and the activity of cytosolic PKC tended to be decreased by Pro, while the activity of total PKC did not change. These results suggest that Pro seems to promote the translocation of PKC from the cytosol to the membrane in the presence of NA, its vasodilator effect may be the comprehensive result of its decreasing effect on the [Ca(2+)](i) and the increasing effect on cAMP and cGMP, as well as its influence on the PKC.

Protective effects of icariin on neurons injured by cerebral ischemia/reperfusion / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It is very important to search for novel anti-ischemia/reperfusion neuroprotective drugs for prevention or treatment of cerebrovascular diseases. Icariin, the major active component of traditional Chinese herb Yinyanghuo, may have a beneficial role for neurons in cerebral ischemia/reperfusion caused by accident. However, it was not clear yet. In this study, we observed the protective effects of icariin on neurons injured by ischemia/reperfusion in vitro and in vivo and investigated its protective mechanism.</p><p><b>METHODS</b>Cerebral cortical neurons of Wistar rats in primary culture were studied during the different periods of oxygen-glucose deprivation and reperfusion with oxygen and glucose. Cell viability was determined by methyl thiazoleterazolium (MTT) assay. The activity of lactate dehydrogenase (LDH) leaked from neurons, cell apoptosis and the concentration of intracellular free calcium were measured respectively. On the other hand, the mice model of transient cerebral ischemia/reperfusion was made by bilateral occlusion of common carotid arteries and ischemic hypotension/reperfusion. The mice were divided into several groups at random: sham operated group, model group and icariin preventive treatment group. The changes of mice behavioral, activities of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) were measured, respectively.</p><p><b>RESULTS</b>Treatment with icariin (final concentration 0.25, 0.5, and 1 mg/L) during ischemia/reperfusion-mimetic incubation in vitro concentration-dependently attenuated neuronal damage with characteristics of increasing injured neuronal absorbance of MTT, decreasing LDH release, decreasing cell apoptosis, and blunting elevation of intracellular calcium concentration. And in vivo the learning and memory abilities significantly decreased, activities of SOD were diminished and MDA level increased obviously in model group, compared with that in sham operated group. But pre-treatment of model mice with icariin (10, 30 and 100 mg/kg, i.g.) significantly blunted the decrease of mice learning, memory ability and SOD activity, and markedly decreased MDA level.</p><p><b>CONCLUSIONS</b>Icariin has protective effects on cerebral ischemia/reperfusion injured neurons. And decreasing cell apoptosis, preventing intracellular calcium concentration elevation and enhancing anti-oxidant capacity may contribute to its protective effects.</p>

Protective effect of ecdysterone on PC12 cells cytotoxicity induced by beta-amyloid25-35 / 中国结合医学杂志

<p><b>OBJECTIVE</b>To examine the protective effect of ecdysterone (ECR) against beta-amyloid peptide fragment(25-35) (Abeta(25-35))-induced PC12 cells cytotoxicity, and to further explore its mechanism.</p><p><b>METHODS</b>Experimental PC12 cells were divided into the Abeta group (treated by Abeta(25-35) 100 micromol/L), the blank group (untreated), the positive control group (treated by Vit E 100 micromol/L after induction) and the ECR treated groups (treated by ECR with different concentrations of 1, 50 and 100 micromol/L). The damaged and survival condition of PC12 cells in various groups was monitored by lactate dehydrogenase (LDH) release and MTT assay. The content of malondialdehyde (MDA) was measured by fluorometric assay to indicate the lipid peroxidation. And the antioxidant enzymes activities in PC12 cells, including superoxide dismutases (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), were detected respectively.</p><p><b>RESULTS</b>After PC12 cells were treated with Abeta(25-35) (100 micromol/L) for 24 hrs, they revealed a great decrease in MTT absorbance and activity of antioxidant enzymes, including SOD, CAT and GSH-Px as well as a significant increase of LDH activity and MDA content in PC12 cells (P < 0.01). When the cells was pretreated with 1-100 micromol/L ECR for 24 hrs before Abeta(25-35) treatment, the above-mentioned cytotoxic effect of Abeta(25-35) could be significantly attenuated dose-dependently, for ECR 50 micromol/L, P < 0.05 and for ECR 100 micromol/L, P < 0.01. Moreover, ECR also showed significant inhibition on the Abeta(25-35) induced decrease of SOD and GSH-Px activity, but not on that of CAT.</p><p><b>CONCLUSION</b>ECR could protect PC12 cells from cytotoxicity of Abeta(25-35), and the protective mechanism might be related to the increase of SOD and GSH-Px activities and the decrease of MDA resulting from the ECR-pretreatment.</p>

Cardiac hypertrophy induced by prostaglandin F(2alpha) may be mediated by calcineurin signal transduction pathway in rats / 生理学报

In this paper, we studied the relationship between the prostaglandin F(2alpha) (PGF(2alpha))-induced cardiac hypertrophy and calcineurin (CaN) signal transduction pathway in vivo and in vitro. Male Sprague-Dawley rats were given a single i.p. injection with monocrotaline (MCT) (60 mg/kg) and then given orally with celecoxib (20 mg/kg) or vehicle once a day for 14 d before (from d 1 to d 14) or after (from d 15 to d 28) right ventricular hypertrophy (RVH) was formed. Body weight (BW), right ventricular weight (RV), left ventricular with septum weight (LV), as well as lung weight were determined. RVH index (RVHI=RV/LV), RV/BW, and lung weight/BW were calculated and histological changes were observed with transmission electron microscope. PGF(2alpha) level, atrial natriuretic peptide (ANP) and CaN mRNA expressions, expression of CaN and its downstream effectors, NFAT(3) and GATA(4) protein were assayed by EIA kit, RT-PCR, and Western blotting, respectively. The cardiomyocyte hypertrophy in primary culture induced by PGF(2alpha) (0.1 micromol/L) was evaluated by measuring the cell diameter, protein content, and ANP mRNA as well as CaN mRNA expressions. It was found that 14 d or 28 d after MCT was given, the RVHI, RV/BW, and lung weight/BW were significantly increased by 47%, 53% and 118%, and by 64%, 94% and 156%, respectively; at the same time PGF(2alpha) levels in RV tissue were increased by 44% and by 51% with increasing RVHI, and elevated expressions of ANP and CaN mRNA, as well as CaN, NFAT(3) and GATA(4) proteins in a positive correlation manner. Furthermore, some histological injuries were found in RV tissue. Celecoxib, a cyclooxygenase inhibitor, obviously blunted the elevation of RVHI, RV/BW, and lung weight/BW no matter it was given before or after RVH. In vitro experiments showed that 0.1 micromol/L PGF(2alpha) significantly increased the cardiomyocyte diameter and protein content, and promoted ANP and CaN mRNA expressions, which was blocked by cyclosporin A, a CaN inhibitor. Our results indicate that PGF(2alpha) may be involved in cardiac hypertrophy induced by MCT in rats through CaN signal transduction pathway.

Effect of ecdysterone on the expression of c-fos in the brain of rats induced by microinjection beta-AP25-35 into the hippocampus / 药学学报

<p><b>AIM</b>To observe the behavior in learning and memory and the expression of c-fos gene from the brain of rats induced by beta-AP25-35, and the intervention of ecdysterone, in order to explore the protective mechanism of ecdysterone on the dysfunction of learning and memory of the rat induced by beta-AP25-35.</p><p><b>METHODS</b>Microinjection of beta-AP25-35 into hippocampus induced learning and memory dysfunction of rats. The learning and memory of rats were observed by Morris Water Maze. The expression of c-fos gene in the brain was detected by immunohistochemistry.</p><p><b>RESULTS</b>The results of Morris Water Maze showed that after rats were microinjected beta-AP25-35 into hippocampus, the rats in model group took longer latency and searching distance compared with the ones in control group (P < 0.01), and the rats in treated group (ECR 4 mg x kg(-1), ECR 8 mg x kg(-1) and nimodipine 7.2 mg x kg(-1)) took shorter latency and searching distance, especially the ECR 8 mg kg(-1) group (P < 0.01). At the same time, after the 5 days training, there was a higher expression of c-fos in hippocampus and cortex from the rats in control group than that in model group (P < 0.01), but in the treated group, there was a relatively higher expression of c-fos, especially the ECR 8 mg x kg(-1) group (P < 0.01).</p><p><b>CONCLUSION</b>Microinjection of beta-AP25-35 into the rat hippocampus resulted in dysfunction of learning and memory. Ecdysterone was shown to improve the learning and memory of the rats and increase the expression of c-fos. Increasing the expression of c-fos is probably one of the most molecular mechanism of its protection.</p>