AIM: To investigate the mechanisms underlying the protective effects of sodium tanshinone IIA sulfonate (STS) in an ischemia-reperfusion (I/R)-induced rat myocardial injury model. METHODS: Male SD rats were iv injected with STS, STS+LY294002 or saline (NS) for 15 d. Then the hearts were subjected to 30 min of global ischemia followed by 2 h of reperfusion. Cardiac function, infarction size and area at risk were assessed. Cell apoptosis was evaluated with TUNEL staining, DNA laddering and measuring caspase-3 activity. In addition, isolated cardiomyocytes of neonatal rats were pretreated with the above drugs, then exposed to H2O2 (200 mol/L) for 1 h. Cell apoptosis was detected using flow cytometric assay. The levels of p-Akt, p-FOXO3A and Bim were examined with immunoblotting. RESULTS: Compared to NS group, administration of STS (20 mg/kg) significantly reduced myocardial infarct size (40.28%±5.36% in STS group vs 59.52%±7.28% in NS group), and improved the myocardial function as demonstrated by the increased values of dp/dtmax, LVDP and coronary flow at different reperfusion time stages. Furthermore, STS significantly decreased the rate of apoptotic cells (15.11%±3.71% in STS group vs 38.21%±7.83% in NS group), and reduced caspase-3 activity to nearly a quarter of that in NS group. Moreover, STS significantly increased the phosphorylation of Akt and its downstream target FOXO3A, and decreased the expression of pro-apoptotic gene Bim. Co-treatment with the PI3K inhibitor LY294002 (40 mg/kg) partially countered the protective effects induced by STS treatment. In isolated cardiomyocytes, STS exerted similar protective effects as shown in the ex vivo I/R model. CONCLUSION: STS pretreatment reduces infarct size and improves cardiac function in an I/R-induced rat myocardial injury model via activation of Akt/FOXO3A/Bim-mediated signal pathway.
AIM: To investigate the mechanisms underlying the protective effects of sodium tanshinone IIA sulfonate (STS) in an ischemia-reperfusion (I/R)-induced ratmyocardial injury model. METHODS: Male SD rats were iv injected with STS, STS+LY294002 or saline (NS) for 15 d. Then the hearts were subjected to 30 min of global ischemia followed by 2 h of reperfusion. Cardiac function, infarction size and area at risk were assessed. Cell apoptosis was evaluated with TUNEL staining, DNA laddering and measuring caspase-3 activity. In addition, isolated cardiomyocytes of neonatal rats were pretreated with the above drugs, then exposed to H2O2 (200 mol/L) for 1 h. Cell apoptosis was detected using flow cytometric assay. The levels of p-Akt, p-FOXO3A and Bim were examined with immunoblotting. RESULTS: Compared to NS group, administration of STS (20 mg/kg) significantly reduced myocardial infarct size (40.28%±5.36% in STS group vs 59.52%±7.28% in NS group), and improved the myocardial function as demonstrated by the increased values of dp/dtmax, LVDP and coronary flow at different reperfusion time stages. Furthermore, STS significantly decreased the rate of apoptotic cells (15.11%±3.71% in STS group vs 38.21%±7.83% in NS group), and reduced caspase-3 activity to nearly a quarter of that in NS group. Moreover, STS significantly increased the phosphorylation of Akt and its downstream target FOXO3A, and decreased the expression of pro-apoptotic gene Bim. Co-treatment with the PI3K inhibitor LY294002 (40 mg/kg) partially countered the protective effects induced by STS treatment. In isolated cardiomyocytes, STS exerted similar protective effects as shown in the ex vivo I/R model. CONCLUSION:STS pretreatment reduces infarct size and improves cardiac function in an I/R-induced ratmyocardial injury model via activation of Akt/FOXO3A/Bim-mediated signal pathway.
Authors: Carmen Urbich; Andrea Knau; Stephan Fichtlscherer; Dirk H Walter; Thomas Brühl; Michael Potente; Wolf K Hofmann; Sven de Vos; Andreas M Zeiher; Stefanie Dimmeler Journal: FASEB J Date: 2005-04-11 Impact factor: 5.191
Authors: B Freude; T N Masters; F Robicsek; A Fokin; S Kostin; R Zimmermann; C Ullmann; S Lorenz-Meyer; J Schaper Journal: J Mol Cell Cardiol Date: 2000-02 Impact factor: 5.000