Neutroprotective efficacy of sodium tanshinone B on hippocampus neuron in a rat model of focal cerebral ischemia / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the protective effects of sodium tanshinone B (STB) on brain damage following focal ischemia-reperfusion (I/R) injury through interfering with N-methyl-D-aspartic acid receptor (NMDAR) and excitatory and inhibitory amino acids, and evaluate the potential mechanisms of the neuroprotective activity of STB.</p><p><b>METHODS</b>Transient forebrain ischemia was induced by middle cerebral artery occlusion (MCAO). The rats were randomized into a sham operated group, a model group (I/R) and three STB different dose groups. Rats were pretreated with STB at the doses of 4, 8, 16 mg/kg (STB(1), STB(2), STB(3)) for 3 days before MCAO. The expression of NMDAR1 was detected by immunohistochemistry and Western blotting. The concentrations of glutamate and γ-aminobutyric acid (GABA) were analyzed using high performance liquid chromatography.</p><p><b>RESULTS</b>STB treatment reduced neurological defect scores, cerebral infarction volume and brain water content. The levels of NMDAR1 were significantly higher in the l/R and STB(1) groups than that of the sham and the STB(3) groups (P<0.01). Optical density of NMDAR1 was significantly increased in cornu ammonis (CA)1 region of the l/R group (P<0.05). STB treatment reduced NMDAR1 optical density in the CA1 region (P<0.01). The levels of glutamate were significantly lower in the hippocampus in the STB(3) group than that of the l/R, STB(1) and STB(2) groups (P<0.01).</p><p><b>CONCLUSION</b>Preconditioning with STB appears to be a simple and promising strategy to reduce or even prevent cerebral l/R injury and has potential for future clinical application.</p>

Effects of sodium tanshinone B on the protein expression of NMDAR1 in rat hippocampal subfields following focal ischemia/reperfusion injury / 中国中西医结合杂志

<p><b>UNLABELLED</b>OBJECTIVE To observe the changing laws of the protein expression of N-methyl D-aspartate receptor (NMDAR) in rat hippocampal subfields following focal ischemia/reperfusion injury, and to study the effects of sodium tanshinone B (STB) on it, thus exploring the possible mechanism of STB for treating cerebral ischemia.</p><p><b>METHODS</b>The rat model of focal cerebral ischemia/reperfusion injury was established using middle cerebral artery occlusion (MCAO) by reversibly inserting a nylon thread. The Wistar rats were randomly divided into the sham-operation group, the I/R model group, and the low, middle, and high dose STB groups. The neural functional disturbance was scored referring to the 5-grade Zea Longa EL standard. The protein expression of NMDAR1 in the ischemic side was detected using immunohistochemical assay.</p><p><b>RESULTS</b>There was statistical difference in the scores of the neural functional disturbance in the middle and high dose STB groups when compared with the model group (P < 0.01). Results of the immunohistochemical assay showed the expression of NMDAR1 in CA1 region was obviously higher in the I/R model group, the low and middle dose STB groups than in the sham-operation group (P < 0.01). The expression of NMDAR1 in CA1 region was obviously lower in the high dose STB group than in the I/R model group (P < 0.01), the low (P < 0.01) and middle dose STB groups (P < 0.05). The expression of NMDAR1 in CA3 region was obviously higher in the low dose STB group and the I/R model group than in the sham-operation group, the middle and high dose STB groups (P < 0.01). The expression of NMDAR1 in CA3 region was obviously higher in the high and middle dose STB groups than in the sham-operation group (P < 0.05).</p><p><b>CONCLUSIONS</b>STB could promote the recovery of neural functions in cerebral ischemia/reperfusion injury rats. STB fought against cerebral ischemia/reperfusion injury by lowering excitable neurotransmitter glumatic acid and reducing the protein expression of NMDAR1.</p>

Effects of salvianolic acid B preconditioning endothelial progenitor cells on expressions of myocardial genes in bone mesenchymal stem cells at the early cell differentiation stage of rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effects of Salvianolic acid B preconditioned endothelial progenitor cells (EPCs) on the Nkx2.5 and GATA-4 gene expressions at the early stage of cell differentiation of bone mesenchymal stem cells (BMSc) transplanted into infarcted myocardium, in order to find out the best synergism for co-transplantation of the two kinds of cells.</p><p><b>METHODS</b>BMSc and EPCs of rats were isolated and cultured, and rats were modeled into acute myocardial infarction (AMI) by left coronary artery ligation. Then the EPCs preconditioned with different concentrations of Salvianolic acid B and BMSc or DMEM medium were implanted into heart ischemia area. Expressions of Nkx2.5 and GATA-4 mRNA expressions in myocardium were detected by Real-time RT-PCR 4 weeks later.</p><p><b>RESULTS</b>Compared with those in the non-implanted model rats' myocardium, the gene expression of Nkx2.5 and GATA-4 mRNA were significantly higher in all the transplantation receptive groups, comparisons between the implanted groups showed that the highest value of expressions (2. 654 +/- 0.606 of Nkx2.5 and 1.573 +/- 0.372 of GATA-4) displayed in the group contained more EPCs, for 8-fold to BMSc in volume.</p><p><b>CONCLUSION</b>BMSc can differentiate into cardiac muscle like cells, and condition of their differentiation is related with the degree of the internal environment improved.</p>