Showing papers by "Jian-Xun Liu published in 2009"

RNA interference-mediated downregulation of Beclin1 attenuates cerebral ischemic injury in rats

Abstract: To test the role of the Beclin 1-dependent autophagy pathway in brain damage during cerebral ischemia. Focal cerebral ischemia was established in rats using a middle cerebral artery occlusion (MCAO) model. A lentiviral vector-associated RNA interference (RNAi) system was stereotaxically injected into the ipsilateral lateral ventricle to reduce Beclin1 expression. We measured the ipsilateral infarct volume, autophagosome formation, neurogenesis and apoptosis, all of which could be modulated by Beclin1 RNAi. On the 14th day after MCAO, Beclin1 downregulation by RNAi increased the population of neural progenitor cells (BrdU+-DCX+), newborn immature cells (BrdU+-Tuj-1+) and mature neurons (BrdU+-MAP-2+), and reduced the apoptosis of immature neurons (caspase-3+-DCX+ and caspase-3+-Tuj-1+) surrounding the ischemic core of the ipsilateral hemisphere. Furthermore, RNAi-mediated downregulation of Beclin1 decreased infarct volume and inhibited histological injury and neurological deficits. RNAi-mediated downregulation of Beclin1 improves outcomes after transient MCAO.

[Protective effect of hawthorn leaf procyanidins on cardiomyocytes of neonatal rats subjected to simulated ischemia-reperfusion injury].

Abstract: OBJECTIVE To study the direct effect of hawthorn leaf procyanidins on cardiomyocytes subjected to ischemia-reperfusion injury and elucidate their therapeutic mechanism on ischemic heart diseases. METHOD Cultured cardiomyocytes of neonatal rats were subjected to anoxia-reoxia injury which simulated the ischemia-reperfusion injury in vivo, and hawthorn leaf procyanidins were applied. The therapeutic effect was valued by LDH leakage and MTT test. For a further mechanism study, contents of MDA and activities of SOD in cardiomyocytes were measured. RESULT Hawthorn leaf procyanidins in 24-60 mg x L(-1) significantly and dose-dependently inhibited LDH leakage (compared with the model group, all P<0.01 ) and cell viability decrease (compared with model group, 24-48 mg x L(-1) groups all P<0.05; 60 mg x L(-1) group, P<0.01) in cardiomyocytes induced by anoxia-reoxia injury. Furthermore, hawthorn leaf procyanidins in 24-60 mg x L(-1) significantly inhibited the increase of MDA content (compared with the model group, all P<0.01) and the decreased of SOD activity (compared with the model group, 24 mg x L(-1) group, P<0.05; other groups all P<0.01) in cardiomyocytes undergoing anoxia-reoxia injury. CONCLUSION Hawthorn leaf procyanidins have a significant therapeutic effect on the simulated ischemia-reperfusion injury of cultured neonatal rat cardiomyocytes, which may relate to their anti-oxidation effects. And the direct protective effect of hawthorn leaf procyanidins on cardiomyocytes subjected to ischemia-reperfusion injury may be one of the key mechanisms of its therapeutic effect on ischemic heart diseases.

Evaluation of different combinations of components of Chinese formulation shuangshentongguan by using AUC values

Abstract: A sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was applied for the quantification of each component: tetrahydropalmatine (THP), dehydrocorydaline (DHC), salvianolic acid B (SAB), ginsenoside Rg1, Re, Rb1 and Rd in the Chinese herbal component SSTG (Shuangshentongguan) with different combinations The pharmacokinetic data were analyzed with WinNonlin 52 software The results showed that combination can increase the THP AUC value while the AUC values of SAB, ginsenoside Rg1, Re, Rb1 and Rd were reduced These results showed significant differences The AUC value of ginsenoside Rb1 was increased when combined with Danshen or Yanhusuo, but reduced when combined with Danshen and Yanhusuo The DHC concentration in serum was too low to be determined