Research advances in chemical constituents and hepatoprotective effect of Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus / 中国中药杂志

Schisandrae has a long history of medicinal use in China. Domestic and foreign scholars have isolated a variety of chemical constituents from Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus, including lignans, volatile oils, polysaccharides, triterpenoids, organic acids, amino acids and so on. Pharmacological studies have shown that their alcohol extracts, water extracts, lignan monomers and polysaccharides could protect liver injury and reduce enzyme ability by a variety of hepatoprotective effects such as enzyme reducing, liver protecting, and antioxidant effect. In this paper, the researches on the chemical composition, hepatoprotective effect and pharmacokinetics of Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus in the past forty years were systematically collated, in order to provide useful enlightenment for the clinical application and new drug development of Schisandrae Sphenantherae Fructus and Schisandrae Chinensis Fructus in liver protection.

The myocardial protective effect of propofol on rats with experimental myocardial infarction and its mechanism / 生理学报

The aim of the present study was to investigate the protective effect of propofol on the experimental myocardial infarction in rats. The myocardial infarction model was established by ligating the anterior descending branch of left coronary artery in rats. Model rats were treated with propofol. Cardiac function was evaluated by echocardiography. Cardiac hemodynamic changes were detected by multiconductor biorecorder. Pathological changes in the infarcted myocardia were detected by HE staining. The expression levels of cardiac hypertrophy marker genes and fibrosis marker proteins were analyzed by real-time quantitative PCR and Western blot. The results showed that, compared with the sham surgery group, the model group exhibited larger infarct size (> 40%), impaired heart function, and significantly increased left ventricular end-diastolic pressure (LVEDP). Propofol reduced cardiac function impairment and decreased LVEDP in the model group. Propofol significantly reduced lung weight/body weight ratio, heart weight/body weight ratio, left ventricular weight/body weight ratio and left atrial weight/body weight ratio in the model group. Furthermore, after myocardial infarction, the administration of propofol significantly improved the diastolic strain rate, down-regulated the mRNA expression levels of myocardial hypertrophy markers, atrial natriuretic peptide and β-myosin heavy chain, and reversed the up-regulation of matrix metalloproteinase 2 (MMP2), MMP9 and tissue inhibitor of metalloproteinase-2 (TIMP-2) induced by myocardial infarction. These results suggest propofol can reduce adverse ventricular remodeling, cardiac dysfunction, myocardial hypertrophy and fibrosis after myocardial infarction, and has protective effect against the experimental myocardial infarction induced by coronary artery ligation in rats.

Effects of ginsenoside Rb1 on the mRNA expression of tyrosine kinase B in the hippocampus of acute immobilization stress rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effects of acute immobilization stress on the mRNA expression of tyrosine kinase B (TrkB) in rats' hippocampus.</p><p><b>METHODS</b>Eighteen SD rats were randomly divided into three groups, i.e., the normal control group, the model group, and the medication group, 6 in each group. The acute immobilization stress model was prepared in the model group using acute immobilization for 2 h. Ginsenoside Rb1 (40 mg/kg) was peritoneally injected to rats in the medication group 30 min before modeling, with the same procedure as those for rats in the model group. No treatment was performed to rats in the normal control group. The plasma adrenocorticotropic hormone (ACTH) and corticosterone (CORT) contents were detected using ELISA. The mRNA expression of TrkB in the rats' hippocampus was detected using real-time fluorescence quantitative RT-PCR.</p><p><b>RESULTS</b>Before modeling there was no statistical difference of plasma CORT or ACTH concentrations among three groups (P >0.05). The plasma CORT and ACTH concentrations increased in the model group and the medication group more significantly after modeling than before modeling, showing statistical difference (P <0.05). Besides, they were obviously higher in the model group than in the normal control group (P <0.05). They were obviously higher in the medication group than in the model control group (P <0.05). Compared with the normal control group, the mRNA expression of TrkB significantly decreased in the model group (87.73 +/- 7.62 vs 50.65 +/- 5.19, P < 0.05), showing statistical difference. The mRNA expression of TrkB was significantly higher in the medication group (78.91 +/- 18.07) than in the model group, showing statistical difference (P <0.05).</p><p><b>CONCLUSION</b>Pretreatment by ginsenoside Rb1 could increase the plasma CORT and ACTH concentrations, maintain the mRNA expression of TrkB, thus relieving injury induced by acute immobilization stress.</p>