Regulation of autophagy by tea polyphenols in diabetic cardiomyopathy / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

OBJECTIVE@#To investigate the effect of tea polyphenols on cardiac function in rats with diabetic cardiomyopathy, and the mechanism by which tea polyphenols regulate autophagy in diabetic cardiomyopathy.@*METHODS@#Sixty Sprague-Dawley (SD) rats were randomly divided into six groups: a normal control group (NC), an obesity group (OB), a diabetic cardiomyopathy group (DCM), a tea polyphenol group (TP), an obesity tea polyphenol treatment group (OB-TP), and a diabetic cardiomyopathy tea polyphenol treatment group (DCM-TP). After successful modeling, serum glucose, cholesterol, and triglyceride levels were determined; cardiac structure and function were inspected by ultrasonic cardiography; myocardial pathology was examined by staining with hematoxylin-eosin; transmission electron microscopy was used to observe the morphology and quantity of autophagosomes; and expression levels of autophagy-related proteins LC3-II, SQSTM1/p62, and Beclin-1 were determined by Western blotting.@*RESULTS@#Compared to the NC group, the OB group had normal blood glucose and a high level of blood lipids; both blood glucose and lipids were increased in the DCM group; ultrasonic cardiograms showed that the fraction shortening was reduced in the DCM group. However, these were improved significantly in the DCM-TP group. Hematoxylin-eosin staining showed disordered cardiomyocytes and hypertrophy in the DCM group; however, no differences were found among the remaining groups. Transmission electron microscopy revealed that the numbers of autophagosomes in the DCM and OB-TP groups were obviously increased compared to the NC and OB groups; the number of autophagosomes in the DCM-TP group was reduced. Western blotting showed that the expression of LC3-II/I and Beclin-1 increased obviously, whereas the expression of SQSTM1/p62 was decreased in the DCM and OB-TP groups (P<0.05).@*CONCLUSIONS@#Tea polyphenols had an effect on diabetic cardiomyopathy in rat cardiac function and may alter the levels of autophagy to improve glucose and lipid metabolism in diabetes.

Expression of extracellular matrix metalloproteinase inducer in the unstable plaque of patients with acute coronary syndrome / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) in the unstable plaque of patients with acute coronary syndrome (ACS), and the impact of leukotriene B4 (LTB4) on the EMMPRIN expression in macrophages.</p><p><b>METHODS</b>The EMMPRIN expression was detected by immunohistochemistry in 11 unstable plaques from patients with ACS. Protein expression of EMMPRIN was evaluated by Western blot on macrophages differentiated from THP-1 which were stimulated with LTB4 in the absence or presence of LTB4 antagonist U75302. There are 8 study groups: 1-THP-1, 2-8-the macrophages derived from THP-1, 2-6-macrophages were stimulated by LTB4 (0, 10(-10), 10(-9), 10(-8) and 10(-7) mol/L) for 24 h, 7-8-the macrophages were pretreated by 10(-6) mol/L or 10(-7) mol/L U75302 2 h before the LTB4 (10(-7) mol/L) stimulation.</p><p><b>RESULTS</b>Abundant EMMPRIN expression was detected in macrophages and smooth muscle cells of unstable plaques from ACS patients. As to the THP-1 derived macrophages, EMMPRIN expression was significantly upregulated in a concentration-dependent manner in LTB4 stimulated groups, which was significantly higher in group 3-6 than in the THP-1 group (group 1) and macrophages group (group 2) (all P < 0.05) and pretreatment with U75302 significantly reduced the LTB4 induced upregulation of EMMPRIN in a dose-dependent manner (P < 0.05).</p><p><b>CONCLUSION</b>EMMPRIN expression is enhanced in macrophages and smooth muscle cells on unstable coronary artery plaques from ACS patients. LTB4 could stimulate EMMPRIN expression on THP-1 derived macrophages suggesting that LTB4 and EMMPRIN might be both involved in the formation and progression of unstable plaques, future studies are warranted to explore if LTB4 and EMMPRIN antagonists are effective or not for treating patients with ACS.</p>

Angiogenesis in chronic ischemic porcine myocardium after transfer of VEGF₁₆₅ and angiopoietin-1 mediated by recombinant adeno-associated viral vector / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study the effects of combination of angiopoietin-1 (ANG-1) and vascular endothelial growth factor₁₆₅ (VEGF₁₆₅) gene transfer mediated by recombinant adeno-associated viral vector on the neovascularization in chronic ischemic porcine myocardium.</p><p><b>METHODS</b>An ameroid constrictor was implanted around the left circumflex coronary artery (LCX) via endoscopy. Six weeks later, coronary angiography revealed that the myocardial ischemia was established by gradual occlusion of the left circumflex coronary artery (LCX). Sixteen swine with the total occlusion or partial stenosis (> 85 %) of the LCX were divided into 4 groups (4 in each group): group I, group II and group IV (control) received direct myocardium injection of rAAV₂ VEGF₁₆₅, rAAV₂ ANG-1 or PBS alone, respectively; group III received rAAV₂ VEGF₁₆₅ and rAAV₂ ANG-1. Selective coronary angiography and ultrasonography were performed perioperatively to evaluate the cardiac function and the formation of collateral circulation. The expression of VEGF₁₆₅ and ANG-1 proteins were assessed using ELISA or Western blot. The degree of angiogenesis was assessed by use of immunohistochemical analysis.</p><p><b>RESULT</b>Angiography showed that the occlusion of all LCX was completed or exceeded 95% 6 weeks after ameroid constrictor implantation, indicating the successful establishment of animal model. The expression levels of VEGF₁₆₅ in group I and III and ANG-1 in groups II and III began to increase at d7 after transfection and reached the peak at d14; then decreased gradually to the normal level after 3 months. The expression levels of VEGF₁₆₅ in group II and group IV or that of ANG-1 protein in group I and group IV had no markedly changes at different time after transfection. There were significant increase in capillary density and arteriole density and more side branch vessels formed in group III compared with other groups. Echocardiographic measurements showed that the left ventricular systolic function of animals in groups I, II and III increased significantly after gene transfection, especially in group III; but there was no changes in group IV.</p><p><b>CONCLUSION</b>Myocardial perfusion and the left ventricular systolic function are improved after rAAV₂ VEGF₁₆₅ or rAAV₂ ANG-1 transfection, which is associated with the angiogenesis in porcine model of chronic myocardial ischemia.</p>

Improvement in cardiac function after sarcoplasmic reticulum Ca2+-ATPase gene transfer in a beagle heart failure model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Heart failure (HF) is a major cause of morbidity and mortality worldwide, but current treatment modalities cannot reverse the underlying pathological state of the heart. Gene-based therapies are emerging as promising therapeutic modalities in HF patients. Our previous studies have shown that recombinant adeno-associated viral (rAAV) gene transfer of Sarco-endoplasmic reticulum calcium ATPase (SERCA2a) can be effective in treating rats with chronic heart failure (CHF). The aim of this study was to examine the effects of SERCA2a gene transfer in a large HF animal model.</p><p><b>METHODS</b>HF was induced in beagles by rapid right ventricular pacing (230 beats/min) for 30 days. A reduced rate ventricular pacing (180 beats/min) was continued for another 30 days. The beagles were assigned to four groups: (a) control group (n = 4); (b) HF group (n = 4); (c) enhanced green fluorescent protein group (n = 4); and (d) SERCA2a group (n = 4). rAAV1-EGFP (1 x 10(12) microg) and rAAV1-SERCA2a (1 x 10(12) microg) were delivered intramyocardially. SERCA2a expression was assessed by Western blotting and immunohistochemistry.</p><p><b>RESULTS</b>Following 30 days of SERCA2a gene transfer in HF beagles its protein expression was significantly higher than in the HF group than in the control group (P < 0.05). Heart function improved along with the increase in SERCA2a expression. Left ventricular systolic function significantly improved, including the ejection fraction, left ventricular systolic pressure, maximal rate of rise of left ventricular pressure (+dp/dt(max)), and the maximal rate of decline of left ventricular pressure (-dp/dt(max)) (P < 0.05). Left ventricular end-diastole pressure significantly decreased (P < 0.05). The expression of SERCA2a in the myocardial tissue was higher in the SERCA2a group than in the HF group (P < 0.05).</p><p><b>CONCLUSIONS</b>Intramyocardial injection of rAAV1-SERCA2a can improve the cardiac function in beagles induced with HF. We expect further studies on SERCA2a's long-term safety, efficacy, dosage and the optimization before using it in humans with HF.</p>

Construction of adeno-associated virus vector containing ANG-1 gene and its expression in pig mesenchymal stem cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct recombinant adeno-associated virus (rAAV) vector containing angiopoietin-1 (ANG-1) gene and to express the ANG-1 in targeting cells.</p><p><b>METHODS</b>ANG-1 cDNA was obtained from human spleen by RT-PCR and was inserted into AAV vectors to form rAAV ANG-1, the virus stocks in high titer were harvested. The rAAVANG-1 and rAAV GFP were transferred into pig mesenchymal stem cells and the expression of ANG-1 was detected by Western blot.</p><p><b>RESULTS</b>The cloned ANG-1 cDNA was 1515bp in length which was in accordance with that reported previously. Titration of rAAVANG-1 stock was 9 X 10(11)v.g/ml. The expression of ANG-1 gene was detected in transfected cells. Forty-eight hours after rAAV GFP was transfected into mesenchymal stem cells, 55% cells expressed GFP.</p><p><b>CONCLUSION</b>The constructed rAAV ANG-1 vector has successfully transfered and expressed in pig mesenchymal stem cells.</p>

Create a standard mini-swine model of chronic ischemic myocardium by thoracoscopy / 中华外科杂志

<p><b>OBJECTIVE</b>To create a standard mini-swine model of chronic ischemic myocardium by endoscopy for the research of gene transfer and stem cell.</p><p><b>METHODS</b>Twenty-three male China experimental minipigs were used, aged from 8 to 11 months with a mean of (9.3 +/- 1.8) months and weighed from 20 to 30 kg with a mean of (29.3 +/- 4.3) kg. The myocardial ischemia was established by gradual occlusion of the left circumflex coronary artery (LCX) with an Ameroid constrictor. The Ameroid constrictor was implanted around LCX by endoscopy. Selective coronary angiography, electrocardiogram and Echo-Doppler study were performed perioperatively to evaluate the degree of stenosis.</p><p><b>RESULTS</b>Chronic ischemic myocardial models were successfully generated in 20 of 23 swine by full-endoscopy. Ameroid constrictors were placed at the LCX accurately. Three swine died of anesthetic accident, cardiac arrhythmia at secondary coronary angiography, and pulmonary infection within 6 weeks after operation respectively. Operation time was 25 to 65 min with a mean of (46 +/- 9) min. The blood loss was 30 to 60 ml with a mean of (55 +/- 12) ml. Six weeks later, coronary angiography revealed the total occlusion and partial stenosis (> 85%) of the LCX occurred in 7 and 13 swine respectively. Cardiac systolic and diastolic dysfunction were found in all swine. The ejection fraction value was (65.0 +/- 6.3)% before operation and (41.0 +/- 9.3)% after operation (P = 0.008). The fractional shortening value was (36.2 +/- 4.3)% before operation and (34.2 +/- 2.3)% after operation (P = 0.027).</p><p><b>CONCLUSION</b>The endoscopic surgery is a less invasive way to create a standard mini-swine model of chronic ischemic myocardium with effective results.</p>

Study of relations between matrix metalloproteinase-9 polymorphism (C-1562T) and acute coronary syndrome in Han population of China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association between acute coronary syndrome (ACS) and functional matrix metalloproteinase-9 polymorphism (C-1562-T).</p><p><b>METHODS</b>This study was conducted with a case-control design including 101 patients with angiographically documented ACS and 105 control subjects who were free from coronary artery disease and had normal angiograms. Genotype was determined by polymerase chain reaction-restriction fragment length polymorphism for the common C-1562-T functional promoter polymorphism of the MMP-9 gene.The relationship between the polymorphism in the MMP-9 gene and the severity of coronary arterial stenosis was analyzed.</p><p><b>RESULTS</b>The results of individual polymorphisms analysis showed that the frequency of C/T and T/T genotypes of the C-1562-T polymorphism (27.2%) in patients with ACS was significantly higher than that in those with a normal angiogram (13.34%).The frequencies of -1562T allele were 14.9% and 7.2% in ACS group and control group respectively (Chi2 = 5.617, P = 0.018). The frequencies of C/T and T/T genotypes of the C-1562-T polymorphism were not statistically different among ACS patients with normal and one,two,three or more significantly diseased vessels (Chi2 = 0.601, P = 0.896).</p><p><b>CONCLUSION</b>The present findings suggest that the genetic polymorphism in MMP-9 promoter (C-1562-T) is associated with the susceptibility to ACS in the Han population of China. And the C-1562-T polymorphism may not be useful as a predictor of the severity of coronary atherosclerosis.</p>