Objective: To investigate the correlation of single nucleotide polymorphisms (SNPs) in autophage-related 5 ( ATG5 ) gene promoter with acute myocardial infarction (AMI). Methods: The SNPs of ATG5 gene promoter were detected by polymerase chain reaction (PCR) and Sanger sequencing. The typing and correlation of SNPs in 378 AMI patients and 374 healthy controls were analyzed by Chi-square test, Logistic regression analysis and haplotype analysis. Results: Two SNPs of ATG5 gene promoter, rs506027 (OR=1.4, 95% CI \[0.6-3.0\], P=0.411) and rs510432 (OR=1.6, 95% CI \[0.7-3.4\], P=0.275), were found. They didn′t increase the susceptibility of AMI, and the haplotype associated with AMI was not found in the two SNPs. Conclusion The polymorphism of ATG5 gene promoter isn′t associated with the susceptibility of AMI.

Objective To investigate the effect of noninvasive positive pressure ventilation treatment on patients with acute left heart failure and hyoxemia.Methods Sixty-two patients with acute left heart failure and hyoxemia were divided into control group (31 cases) and treatment group (31 cases).All patients were treated with a conventional therapy plan and patients in treatment were received noninvasive positive pressure ventilation beside conventional therapy.Blood gas analysis,plasma B-type natriuretic peptide (BNP) and clinical manifestation before and after treatment were monitored.Results The time of clinical manifestation al0leviation in treatment group was (33.7 ±7.9) min,shorter than that of control group ((55.9 ± 12.1) min,t =8.554,P ＜0.01).Compared with pre-treatment,heart rate (HR),respiratory rate(RR),mean arterial pressure(MAP),pH,oxygen saturation of blood (SaO2),arterial partial pressure of oxygen (PaO2),arterial partial pressure of carbon dioxide(PaCO2) and BNP in treatment group were improved significantly(HR:(133.89 ± 5.45) beat/ min vs.(87.27 ± 5.74) beat/min,t =32.794,P ＜ 0.01 ; RR:(34.25 ± 5.67) beat/min vs.(20.15 ± 2.54) beat/min,t =12.636,P ＜ 0.01 ; MAP:(104.52 ± 7.25) mmHg vs.(76.57 ± 3.76) mmHg,t =19.055,P ＜0.01; pH:(7.29±0.06) vs.(7.40 ±0.06),t=7.218,P＜0.01;SaO2:(81.52 ±5.01)％ vs.(97.16±1.27) ％,t =16.848,P ＜ 0.01 ; PaO2:(55.30 ± 7.14) mmHg vs.(92.80 ± 6.24) mmHg,t =22.019,P ＜0.01;PaCO2:(46.23 ±10.30) mmHg vs.(40.56 ±5.19) mmHg,t =2.737,P＜0.05;BNP:(831.59 ±292.65) ng/L vs.(265.52 ±65.39) ng/L,t =10.511,P ＜0.01).And after treatment,HR,RR,MAP,SaO2,PaO2,BNP in control group were improved compared with that before treatment (HR:(132.13 ± 5.31) beat/min vs.(92.15 ± 4.28) beat/min,t =32.638,P ＜ 0.01 ;RR:(34.96 ± 4.78) beat/min vs.(23.91 ± 3.27) beat/min,t=l0.634,P＜0.01;MAP:(102.56 ±7.14) mmHg vs.(82.83±3.52) mmHg,t =13.800,P＜0.01;SaO2:(82.15 ± 5.24) ％ vs.(93.16 ± 2.59) ％,t =10.488,P ＜ 0.01 ; PaO2:(54.56 ± 6.27) mmHg vs.(75.19 ±3.52) mmHg,t =15.974,P ＜0.01 ;BNP:(823.15 ±277.26) ng/L vs.(371.15 ±87.55) ng/L,t =8.656,P ＜0.01).Statistical differences of pH and PaCO2 were not found in the control group before and after treatment(pH:7.32 ± 0.05,t =1.426,P =0.159 ;PaCO2:(43.78 ± 6.74) mmHg,t =0.253,P =0.801).HR,RR,MAP,pH,SaO2,PaO2,PaCO2 and BNP in treatment group were more significantly improved than that of control group(t =3.795,5.056,6.767,5.703,7.721,13.686,2.107 respectively,P ＜ 0.01or P ＜ 0.05).Conclusion The therapy plan of noninvasive positive pressure ventilation on patients with acute left heart failure and hyoxemia can improve cardiac function and oxygenation quickly,and decrease the plasma BNP level.

The purpose of the present study was to examine the effects of oxidative stress on ventricular arrhythmias in rabbits with adriamycin-induced cardiomyopathy and the relationship between oxidative stress and ventricular arrhythmia. Forty Japanese white rabbits were randomly divided into four groups (n=10 in each): control group, metoprolol (a selective β1 receptor blocker) group, carvedilol (a nonselective β blocker/α-1 blocker) group and adriamycin group. Models of adriamycin-induced cardiomyopathy were established by intravenously injecting adriamycin hydrochloride (1 mg/kg) to rabbits via the auri-edge vein twice a week for 8 weeks in the adriamycin, metoprolol and carvedilol groups. Rabbits in the control group were given equal volume of saline through the auri-edge vein. Rabbits in the metoprolol and carvedilol groups were then intragastrically administrated metoprolol (5 mg/kg/d) and carvedilol (5 mg/kg/d) respectively for 2 months, while those in the adriamycin and control groups were treated with equal volume of saline in the same manner as in the metroprolol and carvedilol groups. Left ventricular end diastolic diameter (LVEDd) and left ventricular ejection fraction (LVEF) were measured by echocardiography. Plasma levels of N-terminal pro B-type natriuretic peptide (NT-proBNP), malondialdehyde (MAD) and superoxide dismutase (SOD) were detected. The left ventricular wedge preparations were perfused with Tyrode's solution. The transmural electrocardiogram, transmural action potentials from epicardium (Epi) and endocardium (Endo), transmural repolarization dispersion (TDR) were recorded, and the incidences of triggered activity and ventricular arrhythmias were obtained at rapid cycle lengths. The results showed that TDR and the serum MDA and NT-proBNP levels were increased, and LVEF and the serum SOD level decreased in the adriamycin group compared with the control group. The incidences of triggered activity and ventricular arrhythmia were significantly higher in the adriamycin group than those in the control group (P<0.05). In the carvedilol group as compared with the adriamycin group, the serum SOD level and the LVEF were substantially increased; the TDR, and the serum MDA and NT-proBNP levels were significantly decreased; the incidences of triggered activity and ventricular arrhythmia were obviously reduced (P<0.05). There were no significant differences in the levels of MDA and SOD, LVEF, TDR and the incidences of triggered activity and ventricular arrhythmia between the adriamycin group and the metoprolol group. It was concluded that carvedilol may inhibit triggered activity and ventricular arrhythmias in rabbit with adriamycin-induced cardiomyopathy, which is related to the decrease in oxygen free radials.
Animals ; Anti-Arrhythmia Agents ; administration & dosage ; Antibiotics, Antineoplastic ; Carbazoles ; administration & dosage ; Cardiomyopathies ; chemically induced ; physiopathology ; prevention & control ; Doxorubicin ; Heart Rate ; drug effects ; Male ; Metoprolol ; administration & dosage ; Oxidative Stress ; drug effects ; Propanolamines ; administration & dosage ; Rabbits ; Treatment Outcome ; Ventricular Fibrillation ; chemically induced ; physiopathology ; prevention & control

Pim kinases contribute to tumor formation and development of lymphoma, which shows enhanced DNA replication, DNA recombination and repair. Endothelial cells^(ECs) express all the three members of Pim kinase gene family. We hypothesized that DNA repair gene would regulate Pim expression in ECs. Human umbilical vein endothelial cells (HUVECs) were isolated and maintained in M199 culture medium. The cellular distribution of Pim-3 in ECs was determined by immunofluorescent staining. The siRNA fragments were synthesized and transfected by using Lipofectamine LTX. The total cellular RNA was extracted from the cells by using Trizol reagent. cDNAs were quantified by semi-quantity PCR. The effects of LY294002 and wortmannin on RNA stability in ECs were also examined. Our data showed that LY294002 and wortmannin, phosphatidylinositol 3-kinase (PI3K) and PI3K-like kinase inhibitors, increased Pim mRNA expression in ECs without altering the mRNA stability. RNA interference (RNAi) targeting DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and ataxia telangiectasia mutated (ATM) increased mRNA expression of Pim-3 and Pim-1, respectively. Silencing of Akt decreased Pim-1 instead of Pm-2 and Pim-3 gene expression in ECs. But etoposide, a nucleoside analogue, which could activate DNA-PKcs and ATM, increased Pim expression in ECs. Our study indicates that the expression of Pim kinases is physiologically related to DNA-PKcs and ATM in ECs.

The purpose of the present study was to examine the effects of oxidative stress on ventricular arrhythmias in rabbits with adriamycin-induced cardiomyopathy and the relationship between oxidative stress and ventricular arrhythmia. Forty Japanese white rabbits were randomly divided into four groups (n=10 in each): control group, metoprolol (a selective β1 receptor blocker) group, carvedilol (a nonselective β blocker/α-1 blocker) group and adriamycin group. Models of adriamycin-induced cardiomyopathy were established by intravenously injecting adriamycin hydrochloride (1 mg/kg) to rabbits via the auri-edge vein twice a week for 8 weeks in the adriamycin, metoprolol and carvedilol groups. Rabbits in the control group were given equal volume of saline through the auri-edge vein. Rabbits in the metoprolol and carvedilol groups were then intragastrically administrated metoprolol (5 mg/kg/d) and carvedilol (5 mg/kg/d) respectively for 2 months, while those in the adriamycin and control groups were treated with equal volume of saline in the same manner as in the metroprolol and carvedilol groups. Left ventricular end diastolic diameter (LVEDd) and left ventricular ejection fraction (LVEF) were measured by echocardiography. Plasma levels of N-terminal pro B-type natriuretic peptide (NT-proBNP), malondialdehyde (MAD) and superoxide dismutase (SOD) were detected. The left ventricular wedge preparations were perfused with Tyrode's solution. The transmural electrocardiogram, transmural action potentials from epicardium (Epi) and endocardium (Endo), transmural repolarization dispersion (TDR) were recorded, and the incidences of triggered activity and ventricular arrhythmias were obtained at rapid cycle lengths. The results showed that TDR and the serum MDA and NT-proBNP levels were increased, and LVEF and the serum SOD level decreased in the adriamycin group compared with the control group. The incidences of triggered activity and ventricular arrhythmia were significantly higher in the adriamycin group than those in the control group (P<0.05). In the carvedilol group as compared with the adriamycin group, the serum SOD level and the LVEF were substantially increased; the TDR, and the serum MDA and NT-proBNP levels were significantly decreased; the incidences of triggered activity and ventricular arrhythmia were obviously reduced (P<0.05). There were no significant differences in the levels of MDA and SOD, LVEF, TDR and the incidences of triggered activity and ventricular arrhythmia between the adriamycin group and the metoprolol group. It was concluded that carvedilol may inhibit triggered activity and ventricular arrhythmias in rabbit with adriamycin-induced cardiomyopathy, which is related to the decrease in oxygen free radials.

Pim kinases contribute to tumor formation and development of lymphoma,which shows enhanced DNA replication,DNA recombination and repair.Endothelial cells (ECs) express all the three members of Pim kinase gene family.We hypothesized that DNA repair gene would regulate Pim expression in ECs.Human umbilical vein endothelial cells (HUVECs) were isolated and maintained in M199 culture medium.The cellular distribution of Pim-3 in ECs was determined by immunofluorescent staining.The siRNA fragments were synthesized and transfected by using Lipofectamine LTX.The total cellular RNA was extracted from the cells by using Trizol reagent.cDNAs were quantified by semi-quantity PCR.The effects of LY294002 and wortmannin on RNA stability in ECs were also examined.Our data showed that LY294002 and wortmannin,phosphatidylinositol 3-kinase (PI3K) and PI3K-like kinase inhibitors,increased Pim mRNA expression in ECs without altering the mRNA stability.RNA interference (RNAi) targeting DNA-dependent protein kinase catalytic subunit (DNA-PKcs) and ataxia telangiectasia mutated (ATM) increased mRNA expression of Pim-3 and Pim-1,respectively.Silencing of Akt decreased Pim-1 instead of Pm-2 and Pim-3 gene expression in ECs.But etoposide,a nucleoside analogue,which could activate DNA-PKcs and ATM,increased Pim expression in ECs.Our study indicates that the expression of Pim kinases is physiologically related to DNA-PKcs and ATM in ECs.

In order to investigate the influence of silencing soluble epoxide hydrolase (sEH) with double-stranded small interfering RNA (siRNA) on cardiomyocytes apoptosis induced by doxorubicin (DOX), two plasmids containing siRNA sequences specific to sEH were constructed and transfected into the primary cultured cardiomyocytes by using FuGENE HD transfection agents. The mRNA and protein expression levels of sEH were detected by semiquantitative RT-PCR and Western blotting respectively, and the plasmids that silenced sEH most significantly were selected, and renamed EH-R. The plasmids carrying a nonspecific siRNA coding sequence (PCN) served as the negative control. Cardiomyocytes were divided into four groups: control group, DOX group, PCN+DOX group, and EH-R+DOX group. Apoptosis of cardiomyocytes was induced by DOX at a concentration of 1 μmol/L. Apoptosis rate of cardiomyocytes was determined by flow cytometery. The protein expression levels of Bcl-2 and Bax were detected by Western blotting. The results showed that the expression of sEH was down-regulated by EH-R plasmid. The expression levels of sEH mRNA and protein in the EH-R+DOX group were significantly decreased as compared with other groups (P<0.01). As compared with the control group, the apoptosis rate of cardiomyocytes in three DOX-treated groups was obviously increased, the expression levels of Bax increased, and those of Bcl-2 decreased (P<0.01). However, the expression levels of Bax were decreased, those of Bcl-2 increased and the apoptosis rate of cardiomyocytes obviously decreased in EH-R+DOX group when compared with those in the DOX group and the PCN+DOX group (P<0.01 for each). It was concluded that the recombinant plasmids could be successfully constructed, and transfected into the primary cultured cardiomyocytes. They could ameliorate the DOX-induced cardiomyocytes apoptosis by selectively inhibiting the expression of sEH with RNAi and increasing the expression of Bcl-2.

In order to investigate the influence of silencing soluble epoxide hydrolase (sEH) with double-stranded small interfering RNA (siRNA) on cardiomyocytes apoptosis induced by doxorubicin (DOX),two plasmids containing siRNA sequences specific to sEH were constructed and transfected into the primary cultured cardiomyocytes by using FuGENE HD transfection agents.The mRNA and protein expression levels of sEH were detected by semiquantitative RT-PCR and Western blotting respectively,and the plasmids that silenced sEH most significantly were selected,and renamed EH-R.The plasmids carrying a nonspecific siRNA coding sequence (PCN) served as the negative control.Cardiomyocytes were divided into four groups:control group,DOX group,PCN+DOX group,and EH-R+DOX group.Apoptosis of cardiomyocytes was induced by DOX at a concentration of l μmol/L.Apoptosis rate of cardiomyocytes was determined by flow cytometery.The protein expression levels of Bcl-2 and Bax were detected by Western blotting.The results showed that the expression of sEH was down-regulated by EH-R plasmid.The expression levels of sEH mRNA and protein in the EH-R+DOX group were significantly decreased as compared with other groups (P＜0.01).As compared with the control group,the apoptosis rate of cardiomyocytes in three DOX-treated groups was obviously increased,the expression levels of Bax increased,and those of Bcl-2 decreased (P＜0.01).However,the expression levels of Bax were decreased,those of Bcl-2 increased and the apoptosis rate of cardiomyocytes obviously decreased in EH-R+DOX group when compared with those in the DOX group and the PCN+DOX group (P＜0.01 for each).It was concluded that the recombinant plasmids could be successfully constructed,and transfected into the primary cultured cardiomyocytes.They could ameliorate the DOX-induced cardiomyocytes apoptosis by selectively inhibiting the expression of sEH with RNAi and increasing the expression of Bcl-2.

Plaque rupture,platelet aggregation,and thrombogenesis are the main mechanisms of acute coronary syndrome (ACS),and inflammation factors play key roles in plaque unstability.Psychological stress promotes acute inflammatory response,leading to increased circulating levels of C-reactive protein (CRP),IL-6,and serum intercellular adhesion molecule (sICAM)-1.But it is not clear that whether psychological stress has a direct effect on atherosclerotic plaque stability.The purpose of this study was to investigate effects of chronic psychological stress on inflammatory marker (ICAM-1 ) in atherosclerotic plaque,and inflammatory markers in peripheral blood.Materials and methods Sixty male rabbits were randomized into 2 groups:the control group (n =10) and the atherosclerotic group (n =50).The latter were fed on high fatty diet and were given a large dose of vitamin D3 (3 600 000IU/kg) via intraperitoneal injection.After 8 weeks,the atherosclerotic model was estaslished.Then the 50 atherosclerotic model rabbits were divided into 3 subgroups:no-stress subgroup (n = 16),physiological stress subgroup (n = 16) and psychological stress subgroup (n =18).In physiological stress subgroup and psychological stress subgroup,drinking was cut from twice a day to once a day.At the same time,psychological stress subgroup was given empty bottle stress,and this process lasted for 2 weeks.One hour after the last stress,the blood samples were collected and the serum levels of CRP,IL-6 amd ICAM-1 were tested by radioimmunoassay or enzyme linked immunosorbent assay.The aorta and heart were extracted for pathology examination,and the express of ICAM-1 was tested by immunohistochemical examination.Results (1) After effective atherosclerotic animal model construction,the expression of ICAM-1 in aorta was higher in atherosclerotic group than that in control group (P＜0.01),and was notably higher in psychological stress subgroup than that in no-stress subgroup or in physiological stress subgroup (2.18±0.17 vs 1.58±0.22,1.22±0.15,P＜0.001,respectively).The expression in physiological stress subgroup was higher than that in no-stress subgroup (584±0.22 vs 1.22±0.15,P=0.001).(2) The serum level of IL-6 (51.80±4.60 pg/ml vs 27.60±4.19 pg/ml,8.01±1.39 pg/ml,7.83±1.37 pg/ml),sICAM-1 ( 1.24±0.25 vs 0.85±0.09,0.62±0.17,0.57±0.11),CRP ( 1.004±0.37 vs 0.90±0.29,1.01±0.22,0.71±0.13) in psychological stress group were significantly higher than that in other groups (All P＜0.05).There was a positive relationship between the serum level of CRP,IL-6 and ICAM-1 and the expression of ICAM-1 in aorta wall ( r =0.59,r =0.75,r =0.87,P＜0.01,respectively).Conclusions Psychological stress induces an increased expression of ICAM-1 in aortic atherosclerotic plaque,a higher serum level of CRP,IL-6,and sICAM-1 expression.Psychologial stress has a direct effect on the transition from stability to unstability through in-plaque and out-plaque inflammation.The serum level of CRP,IL-6 and ICAM-1 can reflex the inflammatory degree in atherosclerotic plaque.(J Geriatr Cardiol 2008;5:235-242)

Intracellular Ca2+ and Ca2+-dependent signaling molecule play an essential role in the genesis of long-QT (LQT) syndrome-related ventricular arrhythmias. The effect of calcium-channel antagonist verapamil on repolarization heterogeneity of ventricular myocardium was assessed in an in vitro rabbit model of LQT syndrome. By using the monophasic action potential (MAP) recording technique, MAPs of epicardium, mid-myocardium and endocardium were simultaneously recorded by specially designed plunge-needle electrodes across the left ventricular free wall in rabbit hearts purfused by Langendorff method with standard Tyrode's solution. Bradycardia was induced by com-plete ablation of atrioventrtcular node. A catheter was introduced into the right ventricle to pace at the cycle lengths (CLs) of 1500, 1000, and 500 ms, successively. Quinidine (2 μol/L) prolonged QT in-terval and ventricular MAP duration (MAPD), and increased transmural dispersion of repolarization (TDR) in a reverse rate-dependent fashion in isolated rabbit heart. No polymorphic ventricular tachycardias were induced under this condition. The effective free therapeutic plasma concentrations of verapamil (0.01-0.05 μmol/L) used in this experiment had no effect on quinidine-induced changes of QT interval, MAPD and TDR. This study demonstrated that, in this model of LQT syn- drome, blockade of calcium-channel with verapmil had no effect on quinidine-induced changes of repolatiation heterogeneity of ventricular myocardium.