Background Our previous studies have demonstrated that Tongxinluo （TXL）, a traditional Chinese medicine, can protect hearts against no-reflow and reperfusion injury in a protein kinase A （PKA）-dependent manner. The present study was to investigate whether the PKA-mediated cardioprotection of TXL against no-reflow and reperfusion injury relates to the inhibition of myocardial inflammation, edema, and apoptosis. Methods In a 90-minute ischemia and 3-hour reperfusion model, minipigs were randomly assigned to sham, control, TXL （0.05 g/kg, gavaged one hour prior to ischemia）, and TXL ＋ H-89 （a PKA inhibitor, intravenously and continuously infused at 1.0 μg/kg per minute） groups. Myocardial no-reflow, necrosis, edema, and apoptosis were determined by pathological and histological studies. Myocardial activity of PKA and myeloperoxidase was measured by colorimetric method. The expression of PKA, phosphorylated cAMP response element-binding protein （p-CREB） （Ser133）, tumor necrosis factor a （TNF-a）, P-selectin, apoptotic proteins, and aquaporins was detected by Western blotting analysis. Results TXL decreased the no-reflow area by 37.4% and reduced the infarct size by 27.0% （P〈0.05）. TXL pretreatment increased the PKA activity and the expression of Ser133 p-CREB in the reflow and no-reflow myocardium （P 〈0.05）. TXL inhibited the ischemia-reperfusion-induced elevation of myeloperoxidase activities and the expression of TNF-a and P-selectin, reduced myocardial edema in the left ventricle and the reflow and no-reflow areas and the expression of aquaporin-4, -8, and -9, and decreased myocytes apoptosis by regulation of apoptotic protein expression in the reflow and no-reflow myocardium. However, addition of the PKA inhibitor H-89 counteracted these beneficial effects of TXL. Conclusion PKA-mediated cardioprotection of TXL against no-reflow and reperfusion injury relates to the inhibition of myocardial inflammation, edema, and apoptosis in the reflow and no-reflow myocardium.
LI Xiang-dongYANG Yue-jinCHENG Yu-tongDOU Ke-feiTIAN YiMENG Xian-min
Background The traditional Chinese medicine injury, but the mechanism of its action is not we protective role of Tongxinluo. Tongxinluo can protect myocardium against documented. We examined the involvement schaemia/reperfusion of nitric oxide in the Methods Miniswine were randomized to four groups of seven： sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor N^ωnitro-L-arginine （L-NNA, 10 mg/kg i.v.）. Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively. Results Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA. Conclusions Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase.
Background No-reflow after emergency percutaneous coronary intervention （PCI） for acute ST segment elevation myocardial infarction （STEMI） is related to the severe prognosis. The aim of this study was to evaluate the efficacy of Tongxinluo, a traditional Chinese medicine, on no-reflow and the infarction area after emergency PCI for STEMI.Methods A total of 219 patients （female 31, 14%） undergoing emergency PCI for STEMI from nine clinical centers were consecutively enrolled in this randomized, double-blind, placebo-controlled, multicenter clinical trial from January 2007 to May 2009. All patients were randomly divided into Tongxinluo group （n=108） and control group （n=111）, given Tongxinluo or placebo in loading dose 2.08 g respectively before emergency PCI with asprin 300 mg and clopidogrel 300 mg together, then 1.04 g three times daily for six months after PCI. The ST segment elevation was recorded by electrocardiogram at hospitalization and 1, 2, 6, 12, 24 hours after coronary balloon dilation to evaluate the myocardial no-flow; myocardial perfusion scores of 17 segments were evaluated on day 7 and day 180 after STEMI with static single-photon emission computed tomography （SPECT） to determine the infarct area.Results There was no statistical significance in sex, age, past history, chest pain, onset-to-reperfusion time, Killip classification, TIMI flow grade just before and after PCI, either in the medication treatment during the follow up such as statin, β-blocker, angiotensin converting enzyme inhibitor （ACEI） or angiotensin receptor blocker （ARB） between two groups. There was significant ST segment restoration in Tongxinluo group compared to the control group at 6 hours （（-0.22±0.18） mV vs. （-0.18±0.16） mV, P=0.0394）, 12 hours （（-0.24 ± 0.18） mV vs. （-0.18±0.15） mV, P=0.0158） and 24 hours （（-0.27±0.16） mV vs. （-0.20±0.16） mV, P=0.0021） reperfusion; and the incidence of myocardial no-reflow was also reduced significantly at 24-hour rep
