Yaoming Song

Baseline serum uric acid level as a predictor of cardiovascular disease related mortality and all-cause mortality: a meta-analysis of prospective studies.

OBJECTIVE Serum uric acid (SUA) levels have been used to predict cardiovascular and all-cause mortality event, but the data have yielded conflicting results. We investigated whether SUA was an independent predictor for cardiovascular or all-cause mortality with prospective studies by meta-analysis. METHODS Pubmed and Embase were searched without language restrictions for publications available till April 2013. Only prospective studies on cardiovascular or all-cause mortality related to SUA levels were included. Pooled adjust relative risk (RR) and corresponding 95% confidence intervals (CI) were calculated separately for the highest vs. lowest category or the lowest vs. middle category. RESULTS For the highest SUA, eleven studies with 172,123 participants were identified and analyzed. Elevated SUA increased risk of all-cause mortality (RR 1.24; 95% CI 1.09-1.42) and cardiovascular mortality (RR 1.37; 95% CI 1.19-1.57). Subgroup analyses showed that elevated SUA significantly increase the risk of all-cause mortality among men (RR 1.23; 95% CI 1.08-1.42), but not in women (RR 1.05; 95% CI 0.79-1.39). Risk of cardiovascular mortality appeared to be more pronounced among women (RR 1.35; 95% CI 1.06-1.72). The association between extremely low SUA and mortality was reported in three studies; we did not perform a pooled analysis because of high degree of heterogeneity in these studies. CONCLUSIONS Baseline SUA level is an independent predictor for future cardiovascular mortality. Elevated SUA appears to significantly increase the risk of all-cause mortality in men, but not in women. Whether low SUA levels are predictors of mortality is still inconclusive.

Beneficial effects of a polysaccharide from Salvia miltiorrhiza on myocardial ischemia–reperfusion injury in rats

In the present study, one water-soluble polysaccharide (SMP1) was isolated from the roots of Salvia miltiorrhiza. The cardio-protective potential of SMP1 was studied in the ischemia-reperfusion (I/R) model of rats in vivo. Results showed that 30 min of left anterior descending coronary artery occlusion (LAD) followed by 4 h of reperfusion markedly decreased myocardial superoxide dismutase (SOD), Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase activities and increased myocardial malondialdehyde (MDA) level and serum activities of creatine kinase (CK) and lactate dehydrogenase (LDH) in I/R rats. An increase in infarct size and high apoptosis index of cardiac cell were also observed in IR rats. Administration of SMP1 400 and 800 mg/kg significantly reversed these biochemical parameters in the I/R rats to the normal levels in sham control rats. The infarct sizes and the percent of TUNEL-positive cells were found significantly decreased in SMP1-treated groups compared to I/R rats. Taken together, the present study clearly suggests SMP1 has a protective effect against myocardial I/R injury in rats by ameliorating oxidative stress and inhibiting myocardial apoptosis.

Cardiovascular effects in vitro of a polysaccharide from Salvia miltiorrhiza.

A polysaccharide (SMP1) was isolated from the roots of Salvia miltiorrhiza. This study is designed to investigate whether SMP1 prevents H9c2 cells from hydrogen peroxide (H2O2)-induced apoptosis. The present study showed that exposure of H9c2 cells to 100mM H2O2 for 24h caused a significant increase in cell death and apoptosis, but pretreatment with SMP1 eliminated H2O2-induced apoptotic cell death. Furthermore, pretreatment with SMP1 significantly prevented the mitochondria disruption, cytochrome c release, the rise of the ratio between proapoptotic Bax and antiapoptotic Bcl-2 protein expression, and caspase-3 activation in H9c2 cells upon H2O2 stimulation. Moreover, the decline of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities together with the elevation of malondialdehyde (MDA) in PC12 cells exposed to H2O2 were remarkably reversed to normal levels by pretreatment with SMP1. These results suggest that SMP1 protects H9c2 cells from H2O2-induced apoptosis through inhibition of mitochondrial dysfunction, inactivation of caspase-3 cascade and enhancement of antioxidant capacity.

Protective effect of a polysaccharide from Salvia miltiorrhiza on isoproterenol (ISO)-induced myocardial injury in rats

In this study, we investigated the cardioprotective effect of one purified polysaccharide (SMP1) from Salvia miltiorrhiza on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. ISO-treated rats showed severe myocardial damage and high lipid peroxidation level, as well as decreased endogenous myocardial antioxidant function. Pretreatment with SMP1 (100 and 400mg/kg) for 30 days significantly increased the body weight, decreased the heart weight, attenuated the serum levels of creatine kinase (CK), creatine phospokinase-MB (CK-MB), dehydrogenase (LDH), alkaline phosphate (ALP), aspartate transaminase (AST), alanine transaminase (ALT), total cholesterol, triglyceride, and LDL-cholesterol (LDL-C), along with the increased concentration of HDL-cholesterol (HDL-C). In addition, SMP1 also enhanced myocardial superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities and elevated myocardial reduced glutathione (GSH) level, along with a decrease in thiobarbituric acid reactive substances (TBARS) concentration. Collectively, our results indicated that long-term oral administration of SMP1 offered significant protection against the damage induced by ISO in rat heart through enhancement of endogenous antioxidants and antihyperlipidemic activity.

Effect of Paclitaxel and Mesenchymal Stem Cells Seeding on Ex Vivo Vascular Endothelial Repair and Smooth Muscle Cells Growth

Late thrombosis and neointima proliferation after paclitaxel-eluting stents implanting may be related to delayed endothelial cells (ECs) regeneration. This study was to investigate whether mesenchymal stem cells (MSCs) seeding can accelerate endothelial repair and attenuate late smooth muscle cells (SMCs) proliferation after paclitaxel intervention. An ex vivo model of endothelium repair was developed in which rabbit smooth muscle cells were inoculated in the upper chamber and rabbit endothelial cells/human mesenchymal stem cells in the lower chamber of a co-culture system. Paclitaxel (10 nmol/L, 20 min) inhibited smooth muscle cell growth of the confluent endothelial cell group during the observed period. However, increased smooth muscle cells growth was observed in the proliferative endothelial cells group 10 days after paclitaxel intervention. Mesenchymal stem cell seeding inhibited late smooth muscle cell growth incompatible with the effect of proliferative endothelial cells. However, no inhibition on smooth muscle cell growth was observed with mesenchymal stem cell seeding in comparison to the effect of confluent endothelial cells. No vWF but Flk-1 protein was observed in the 25.71% of mesenchymal stem cells after having been co-cultured with rabbit endothelial cells for 5 days. These results indicate that late smooth muscle cell proliferation is closely related to the delayed endothelial cells regeneration after paclitaxel application. Mesenchymal stem cell seeding partly attenuates the late smooth muscle cell proliferation. Mesenchymal stem cells co-cultured with mature endothelial cells have the ability to differentiate toward endothelial cells.

Isolation and Characterization of Human Coronary Artery-Derived Endothelial Cells in vivo from Patients Undergoing Percutaneous Coronary Interventions

Background/Aims: Human coronary artery-derived endothelial cells (ECs) seem to be the most appropriate cells for the pathogenesis study of coronary artery disease. But limited availability of endothelial tissue is a major constraint. In this study, we developed a method to isolate human coronary artery ECs in vivo from patients. Methods: Coronary guidewires were used to obtain EC samples from coronary arteries in 76 patients. Cells were eluted from wire tips and purified by immunomagnetic beads. Von Willebrand factor and CD31 were used as immunocytochemical markers to identify cells as endothelium. Cell viability was evaluated in terms of cell membrane integrity, energy-dependent uptake of DiI-labeled acetylated low-density lipoprotein, and apoptosis. Nitric oxide synthase (eNOS) expression and nitric oxide (NO) production of cells were detected to evaluate cell function. Results: About 96 coronary artery ECs were obtained per guidewire. Cells manifested endothelial morphology and immunoreactivity for von Willebrand factor and CD31 with good viability. But eNOS expression and NO production of cells were decreased. Conclusions: Viable coronary endothelium could be obtained during routine percutaneous coronary interventions combined with immunomagnetic beads. These cells may be used for advanced cellular functional analyses such as immunocytochemistry and molecular biology. Such information could aid in understanding mechanisms of coronary artery diseases.

Value of Myocardial Regional Perfusion on Long-Term Function in Collateral-Dependent Myocardium

Background: Collateral circulation is considered key for left ventricular (LV) function recovery in patients with chronic total occlusion (CTO). However, there are conflicting reports about the influence of collaterals on LV recovery after revascularization. Methods: Echocardiographic assessment of regional myocardial perfusion, wall motion score (WMS), and left ventricular ejection fraction (LVEF) were performed in patients with angiographically visible collateral circulation of grades 2 and 3. Results: The WMS and LVEF of group B (with presence of myocardial regional perfusion) were significantly improved at one month and six months compared to those of group A (with absence of myocardial regional perfusion). The correlation between myocardial regional blood flow and changes in WMS and LVEF was significant at 6 months in patients with angiographically visible collateral circulation of grade 2 and 3. Similar correlations were observed on myocardial contrast echocardiography (MCE) score index. Conclusion: Myocardial function recovery in patients with CTO is determined by myocardial regional perfusion. MCE has important value for prognosis and risk stratification in patients with CTO undergoing cardiac catheterization.

N-terminal pro-brain natriuretic peptide and cardiovascular or all-cause mortality in the general population: A meta-analysis

The prognostic role of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the general population remains controversial. We conducted this meta-analysis to investigate the association between baseline NT-proBNP concentrations and cardiovascular or all-cause mortality in the general population. PubMed and Embase databases were systematically searched from their inception to August 2016. Prospective observational studies that investigated the association between baseline NT-proBNP concentrations and cardiovascular or all-cause mortality in the general population were eligible. A summary of the hazard ratio (HR) and 95% confidence interval (CI) of mortality were calculated by the highest versus the lowest category of NT-proBNP concentrations. Eleven studies with a total of 25,715 individuals were included. Compared individuals in the highest with those in the lowest category of NT-proBNP, the pooled HR was 2.44 (95% CI 2.11–2.83) for all-cause mortality, 3.77 (95% CI 2.85–5.00) for cardiovascular mortality, and 2.35 (95% CI 1.45–3.82) for coronary heart disease mortality, respectively. Subgroup analyses indicated that the effects of NT-proBNP on the risk of cardiovascular mortality (RR 2.27) and all-cause mortality (RR 3.00) appeared to be slightly lower among men. Elevated NT-proBNP concentrations appeared to be independently associated with increased risk of cardiovascular and all-cause mortality in the general population.

Comparison of collagen versus adenosine diphosphate in detecting antiplatelet effect in patients with coronary artery disease.

Widely varying methods of assessing platelet aggregation have resulted in the absence of an established standard approach to assess the effects of antiplatelet drugs. The objective of this study was to compare the roles of collagen and adenosine diphosphate (ADP) in the assessment of effects of aspirin or clopidogrel on platelet aggregation. Sixty patients with documented coronary artery disease were assigned to receive aspirin alone (ASA 100 mg/d) (n=30) or aspirin-plus-clopidogrel (ASA 100 mg/d+C 75 mg/d) (n=30). Platelet aggregation assessment by the use of whole blood aggregation tests with collagen or ADP was performed in these patients and 30 age- and gender-matched normal volunteers. When compared with the control group, therapy with ASA or ASA+C resulted in significant inhibition of collagen-induced platelet aggregation (P<0.001 for each), but there was no statistically significant difference in the results between the ASA and ASA+C groups. When platelet aggregation was induced by ADP, the combined therapy with aspirin and clopidogrel decreased platelet aggregation significantly when compared with aspirin alone (P<0.001), and no significant difference in the results between the ASA and normal groups was observed. In conclusion, collagen may prove useful to study the effect of aspirin and ADP may be appropriate for assessing the inhibitory effect of clopidogrel.

Association between Low Free Triiodothyronine Levels and Poor Prognosis in Patients with Acute ST-Elevation Myocardial Infarction

Background Low free triiodothyronine (fT3) levels are generally associated with poor prognosis in patients with heart diseases, but this is controversial and there is a lack of data about ST-elevation myocardial infarction (STEMI) in Chinese patients. Objective To assess the association between fT3 levels and the prognosis of patients with STEMI. Methods This was a prospective observational study of 699 consecutive patients with STEMI treated at the Xinqiao Hospital between January 1, 2013, and December 31, 2014. The patients were divided into the low fT3 (fT3 < 3.1 pmol/L; n = 179, 27.5%) and normal fT3 (fT3 ≥ 3.1 pmol/L; n = 473, 72.5%) groups according to fT3 levels at admission. Patients were followed up at 1, 3, 6, and 12 months for all-cause death and major adverse cardiac events (MACE). Results During the 1-year follow-up, there were 70 all-cause deaths (39.1%) in the low fT3 group and 40 (8.5%) in the normal fT3 group (P < 0.001). MACE occurred in 105 patients (58.7%) in the low fT3 group and 74 (15.6%) in the normal fT3 group (P < 0.001). Multivariate Cox proportional hazards regression analysis indicated that fT3 levels were independently associated with 30-day and 1-year all-cause death [30-day: hazard ratio (HR) = 0.702, 95% confidence interval (95% CI): 0.501–0.983, P = 0.04; 1-year: HR = 0.557, 95% CI: 0.411–0.755, P < 0.001] and MACE (30-day: HR = 0.719, 95% CI: 0.528–0.979, P = 0.036; 1-year: HR = 0.557, 95% CI: 0.445–0.698, P < 0.001). Conclusion Low fT3 levels were strongly associated with poor prognosis in patients with STEMI. Measurement of fT3 levels may be a valuable and simple way to identify high-risk STEMI patients.