Optimal time for mesenchymal stem cell transplantation in rats with myocardial infarction

Background:Bone marrow mesenchymal stem cell (MSC) transplantation is a promising strategy in the treatment of myocardial infarction (MI). However, the time for transplanting cells remains controversial. The aim of this study was to find an optimal time point for cell transplantation. Methods: MSCs were isolated and cultured from Sprague-Dawley (SD) rats. MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery. MSCs were directly injected into the infarct border zone at 1 h, 1 week and 2 weeks after MI, respectively. Sham-operated and MI control groups received equal volume of phosphate buffered saline (PBS). At 4 weeks after MI, cardiac function was assessed by echocardiography; vessel density was analyzed on hematoxylin-eosin stained slides by light microscopy; the apoptosis of cardiomyocytes was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay; the expressions of proteins were analyzed by Western blot. Results: MSC transplantation improved cardiac function, reduced the apoptosis of cardiomyocytes and increased vessel density. These benefits were more obvious in 1-week group than in 1-h and 2-week groups. There are more obvious in-creases in the ratio of bcl-2/bax and the expression of vascular endothelial growth factor (VEGF) and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups. Conclusion: MSC transplantation was beneficial for the recovery of cardiac function. MSC transplantation at 1 week post-MI exerted the best effects on increases of cardiac function, anti-apoptosis and angiogenesis.

Acid Water-ground Nano-realgar Is Superior to Crude Realgar in Promoting Apoptosis of MCF-7 Breast Cancer Cells

Objective:Realgar is a traditional mineral Chinese medicine with antitumor effects,but it has high toxicity and low efficacy in its crude form.The purpose of this study was to optimize realgar to increase its efficacy and therapeutic potential.Methods:Crude realgar(CR)was mechanically ground to obtain nano-realgar(NR),and then nano-realgar processed products(NRPPs)were obtained using three different traditional Chinese medicine processing methods:grinding in water,acid water,and alkali water,respectively.Results:By analyzing the size distribution of nanoparticles and the content of arsenic trioxide(As_(2)O_(3);ATO),we found that acid water-ground NRPPs had the characteristics of high purity and low toxicity.The effects of CR,NR,and NRPPs on proliferation,cell cycle,and apoptosis of MCF-7 cells were detected,and the ability of NRPPs to induce apoptosis in MCF-7 cells was analyzed.The results showed that the average particle size of acid water-ground NRPPs was 137.7 nm,and the content of ATO was 2.83 mg/g.Acid water-ground NRPPs showed better effects on inhibiting proliferation,cell cycle,and apoptosis of MCF-7 cells than CR and NR.Western blot assays further confirmed that acid water-ground NRPPs upregulated the protein expression of TP53,Bax,cytochrome c,caspase-9,and caspase-3 in MCF-7 cells(P<0.05)and inhibited the expression of Bcl-2(P<0.05).Conclusion:These results suggest that acid water-ground NRPPs can induce apoptosis of MCF-7 cells through regulating mitochondrial-mediated apoptosis,providing evidence for the clinical application of realgar.

Effects of Percutaneous Coronary Intervention on Serum Angiopoietin-2 in Patients with Coronary Heart Disease

Background： Angiopoietin-2 （Ang-2） plays a crucial role in hypoxia-induced angiogenesis and is expressed only in sites of vascular remodeling. Ang-2 expression can be regulated by hypoxia inducible factors and other regulators with exposure to hypoxia. The objective of this study was to investigate the influence of percutaneous coronary intervention （PCI） on serum Ang-2 concentrations, and analyze the correlation between serum Ang-2 and the severity of coronary artery stenosis in patients with coronary heart disease （CHD）. Methods： Sixty-four patients with CHD were selected as the study group, each undergone PC1. Thirty-two healthy subjects were selected as the control group. Pre-PCI and post-PCl serum Ang-2 were measured by enzyme-linked immunosorbent assay. The severity of coronary artery stenosis was evaluated using angiographic Gensini scores, and the coronary collateral vessels were scored according to Rentrop＇s classification. Results： Concentrations of pre-PCI serum Ang-2 in the study group were significantly higher than those in the control group （4625.06 ~ 1838.06 vs. 1945.74 ：k 1588.17 pg/ml, P 〈 0.01 ）; however, concentrations of post-PCl serum Ang-2 were significantly lower than those of pre-PCI （3042.63 ＋ 1845.33 pg/ml vs. 4625.06 .k 1838.06 pg/ml, P 〈 0.01）. Concentrations of pre-PCl serum Ang-2 were significantly correlated with Gensini scores （r= 0.488, P〈 0.01）; however, the decrease in serum Ang-2 after PC1 was not correlated with Gensini scores, coronary collateral vessel grading, or left ventricular ejection fraction. Conclusions： Serum Ang-2 concentrations significantly increased in patients with CHD, and PCI treatment significantly decreased these concentrations. Serum Ang-2 concentrations, but not the decrease in serum Ang-2 concentrations, were significantly correlated with the severity of coronary artery stenosis. These results suggested that Ang-2 may be a biomarker of myocardial ischemia and vessel remodeling.