Associations Between Insulin Resistance Indexes and Hyperuricemia in Hypertensive Population / 中国医学科学院学报

Objective To explore the relationship between insulin resistance (IR) indexes and hyperuricemia (HUA) among the people with hypertension. Methods From July to August in 2018,hypertension screening was carried out in Wuyuan county,Jiangxi province,and the data were collected through questionnaire survey,physical measurement,and biochemical test.Logistic regression was performed to analyze the relationship between HUA and IR indexes including metabolic score for IR (METS-IR),triglyceride-glucose (TyG) index,TyG-body mass index (BMI),TyG-waist circumference (WC),visceral adiposity index (VAI),triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C),and lipid accumulation product (LAP).The penalty spline method was used for the curve fitting between IR indexes and HUA.The area under the receiver operating characteristic curve (AUC) was employed to reveal the correlation between each index and HUA. Results The 14 220 hypertension patients included 6 713 males and 7 507 females,with the average age of (63.8±9.4) years old,the average uric acid level of (418.9±120.6) mmol/L,and the HUA detection rate of 44.4%.The HUA group had higher proportions of males,current drinking,current smoking,diabetes,and using antihypertensive drugs,older age,higher diastolic blood pressure,WC,BMI,homocysteine,total cholesterol,TG,low-density lipoprotein cholesterol,blood urea nitrogen,creatinine,aspartate aminotransferase,alanine aminotransferase,total protein,albumin,total bilirubin,direct bilirubin, METS-IR, TyG, TyG-BMI, TyG-WC, VAI, TG/HDL-C, and LAP, and lower systolic blood pressure and HDL-C than the normal uric acid group (all P<0.05).Multivariate Logistic regression showed that METS-IR (OR=1.049,95%CI=1.038-1.060, P<0.001), TyG (OR=1.639,95%CI=1.496-1.797, P<0.001), TyG-BMI (OR=1.008,95%CI=1.006-1.010, P<0.001), TyG-WC (OR=1.003,95%CI=1.002-1.004, P<0.001), lnVAI (OR=1.850, 95%CI=1.735-1.973, P<0.001), ln(TG/HDL-C) (OR=1.862,95%CI=1.692-2.048, P<0.001),and lnLAP (OR=1.503,95%CI=1.401-1.613,P<0.001) were associated with the risk of HUA.Curve fitting indicated that METS-IR,TyG,TYG-BMI,TYG-WC,lnVAI,ln(TG/HDL-C),and lnLAP were positively correlated with HUA (all P<0.001),and the AUC of TyG index was higher than that of other IR indexes (all P<0.05). Conclusion Increased IR indexes,especially TyG,were associated with the risk of HUA among people with hypertension.

Predictive Effects of Different Insulin Resistance Indexes on Diabetes Risk in Hypertensive Population / 中国医学科学院学报

Objective To explore the roles of different insulin resistance indexes[triglyceride-glucose (TyG),triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C),and metabolic score for insulin resistance (METS-IR)]and combinations of two indexes in predicting diabetes risk in hypertensive population. Methods The survey of hypertension was conducted for the residents in Wuyuan county,Jiangxi province from March to August in 2018.The basic information of hypertensive residents was collected by interview.Blood was drawn on an empty stomach in the morning and physical measurements were carried out.Logistic regression model was employed to analyze the relationship between different insulin resistance indexes and diabetes,and the area under the receiver operating characteristic curve was used for evaluating the predictive effects of each index on diabetes risk. Results A total of 14 222 hypertensive patients with an average age of (63.8±9.4) years old were included in this study,including 2616 diabetic patients.The diabetic hypertensive population had higher TyG (t=50.323,P<0.001),TG/HDL-C (Z=17.325,P<0.001),and METS-IR (t=28.839,P<0.001) than the non-diabetic hypertensive population.Multivariate analysis showed that each insulin resistance index was positively correlated with diabetes risk.The area under curve of each insulin index was in a descending order of TyG (0.770)> METS-IR (0.673)> TG/HDL-C (0.620).The difference in the area under curve between two indexes was statistically significant[TyG vs.TG/HDL-C (Z=42.325,P<0.001);TyG vs.METS-IR(Z=17.517,P<0.001);METS-IR vs.TG/HDL-C (Z=10.502,P<0.001)]. Conclusions Elevated insulin resistance indexes can increase the risk of diabetes.TyG and the combination of indexes outperform TG/HDL-C and METS-IR in the prediction of diabetes.

Independent and joint association of physical activity and sedentary behavior on all-cause mortality / 中华医学杂志(英文版)

BACKGROUNDS@#Physical activity (PA) and sedentary behavior (SB) have been associated with mortality, while the joint association with mortality is rarely reported among Chinese population. We aimed to examine the independent and joint association of PA and SB with all-cause mortality in southern China.@*METHODS@#A cohort of 12,608 China Hypertension Survey participants aged ≥35 years were enrolled in 2013 to 2014, with a follow-up period of 5.4 years. Baseline self-reported PA and SB were collected via the questionnaire. Kaplan-Meier curves (log-rank test) and Cox proportional hazards regression were performed to evaluate the associations of PA and SB on all-cause mortality.@*RESULTS@#A total of 11,744 eligible participants were included in the analysis. Over an average of 5.4 years of follow-up, 796 deaths occurred. The risk of all-cause mortality was lower among participants with high PA than those with low to moderate level (5.2% vs. 8.9%; hazards ratio [HR]: 0.75, 95% confidence interval [CI]: 0.61-0.87). Participants with SB ≥ 6 h had a higher risk of all-cause mortality than those with SB <6 h (7.8% vs. 6.0%; HR: 1.37, 95% CI: 1.17-1.61). Participants with prolonged SB (≥6 h) and inadequate PA (low to moderate) had a higher risk of all-cause mortality compared to those with SB < 6 h and high PA (11.2% vs. 4.9%; HR: 1.67, 95% CI: 1.35-2.06). Even in the participants with high PA, prolonged SB (≥6 h) was still associated with the higher risk of all-cause mortality compared with SB < 6 h (7.0% vs. 4.9%; HR: 1.33, 95% CI: 1.12-1.56).@*CONCLUSIONS@#Among Chinese population, PA and SB have a joint association with the risk of all-cause mortality. Participants with inadequate PA and prolonged SB had the highest risk of all-cause mortality compared with others.

Predictive value of four score systems on the bleeding risk in atrial fibrillation patients treated with dabigatran / 中华心血管病杂志

Objective: To compare the predictive value of HAS-BLED, HEMORR2HAGES, ATRIA and ORBIT scores on the bleeding risk in nonvalvular atrial fibrillation (NVAF) patients treated with dabigatran. Methods: Data of 942 NVAF patients participating a non-interventional prospective study of anticoagulant therapy with dabigatran, which was conducted in 12 centers from February 2015 to December 2017 in China, were analyzed. Complete HAS-BLED HEMORR2HAGES, ATRIA and ORBIT bleeding risk scores data and follow-up data were available in the enrolled patients. The endpoint of the study was bleeding events occurred during a 6 months follow-up. Cox proportional hazards models were constructed to analyze the associations between HAS-BLED, HEMORR2HAGES, ATRIA and ORBIT scores and risk of bleeding, and the area under the curve (AUC) of receiver operating characteristics curves (ROC) of each score was used to set the predictive value for bleeding risk. Results: Among the 942 patients, the mean age was (65.3±11.2) years old, 542 (57.5%) were males. A total of 93 (9.9%) bleeding events occurred during follow up, 89 (9.4%) events were minor bleeding, and 4 (0.4%) events were major bleeding. Patients with a high-risk HAS-BLED score had a 1.87-fold increased risk of bleeding compared with low-risk patients (HR = 2.87, 95% CI:1.26-6.51, P = 0.012). There was no statistically significant difference between low-medium-high-risk grading in other scoring systems and bleeding risk (all P>0.05). The AUC (95%CI) of HAS-BLED, HEMORR2HAGES, ATRIA and ORBIT bleeding risk scores were 0.558 (0.525-0.590), 0.520 (0.487-0.553), 0.513(0.480-0.545), 0.523(0.490-0.555), respectively. The AUC of all bleeding score systems were of ≤ 0.700. Conclusion: Among the NVAF patients taking dabigatran in China, the HAS-BLED bleeding risk score is superior to other 3 bleeding risk score on predicting the bleeding risk in these patients, but its predictive value is still relatively low.

Low deceleration capacity is associated with higher stroke risk in patients with paroxysmal atrial fibrillation / 中华医学杂志(英文版)

BACKGROUND@#Deceleration capacity (DC) is a non-invasive marker for cardiac autonomic dysfunction; however, few studies have shown that the influence factors of cardiac autonomic dysfunction and the correlations between DC and stroke risk in paroxysmal atrial fibrillation (AF). We aimed to explore the influencing factors of abnormal DC and the relationships between DC and stroke risk in patients with paroxysmal AF.@*METHODS@#The study included hospitalized paroxysmal AF patients with DC measurements derived from 24-h Holter electrocardiography recordings taken between August 2015 and June 2016. Multivariable regression analysis was performed to evaluate the associations between correlated variables and abnormal DC values. The relationship between DC and ischemic stroke risk scores in patients with paroxysmal AF was analyzed.@*RESULTS@#We studied 259 hospitalized patients with paroxysmal AF (143 [55.2%] male, mean age 66.4 ± 12.0 years); 38 patients of them showed abnormal DC values. In the univariate analysis, age, hypertension, heart failure, and previous stroke/transient ischemic attack (TIA) were significantly associated with abnormal DC values. Among these factors, a history of previous stroke/TIA (odds ratio = 2.861, 95% confidence interval: 1.356-6.039) were independently associated with abnormal DC values in patients with paroxysmal AF. The abnormal DC group showed a higher stroke risk with the score of congestive heart failure, hypertension, age >75 years, diabetes mellitus, previous stroke and TIA (CHADS2) (2.25 ± 1.48 vs. 1.40 ± 1.34, t = -4.907, P = 0.001) and CHA2DS2-vascular disease, age 65-74 years and female category (VASc) (3.76 ± 1.95 vs. 2.71 ± 1.87, t = -4.847, P = 0.001) scores. Correlation analysis showed that DC was negatively correlated with CHADS2 scores (r = -0.290, P < 0.001) and CHA2DS2-VASc scores (r = -0.263, P < 0.001).@*CONCLUSIONS@#Lower DC is closely associated with previous stroke/TIA, and is also correlated negatively with higher stroke risk scores in patients with paroxysmal AF. It could be a potential indicator of stroke risk in paroxysmal AF patients.

Peripheral leukocyte count and risk of bleeding in patients with non-valvular atrial fibrillation taking dabigatran: a real-world study / 中华医学杂志(英文版)

BACKGROUND@#The association between peripheral leukocyte count and bleeding events in nonvalvular atrial fibrillation (NVAF) patients treated with dabigatran remains unclear. This study aimed to explore the association between leukocyte count and bleeding events after excluding other confounders in NVAF patients taking dabigatran.@*METHODS@#A total of 851 NVAF patients treated with dabigatran (110 mg bid) were recruited from 12 centers in China from February 2015 to December 2017. Follow-up was completed by May 2018. The exposure and outcome variables were leukocyte count measured at baseline and the number of bleeding events within the subsequent 6 months. Multivariate Cox proportional hazards models were constructed to analyze independent associations, and a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (penalized spline method) was used to address nonlinearity between leukocyte count and bleeding. The inflection point was calculated using a recursive algorithm, and then a two-piecewise Cox proportional hazards model for both sides of the inflection point was constructed.@*RESULTS@#During 6-month follow-up, 87 participants occurred bleeding events. For every 1 × 10/L increase in leukocyte count, the risk of bleeding increased by 11% (hazard ratio [HR]: 1.11, 95% confidence interval [CI]: 0.99-1.25). The smooth curve showed nonlinear relationship between leukocyte count and bleeding events. The inflection point of the leukocyte count was 6.75 × 10/L. For leukocyte counts < 6.75 × 10/L, the HR (95% CI) was 0.88 (0.69-1.13), and for leukocyte counts ≥ 6.75 × 10/L, the HR (95% CI) was 1.28 (1.09-1.51).@*CONCLUSION@#This study found a J-shaped association between baseline leukocyte count and risk of bleeding in NVAF patients treated with dabigatran.@*CLINICAL TRIAL REGISTRATION@#NCT02414035, https://clinicaltrials.gov.

Peripheral leukocyte count and risk of bleeding in patients with non-valvular atrial fibrillation taking dabigatran: a real-world study / 中华医学杂志(英文版)

Background@#The association between peripheral leukocyte count and bleeding events in nonvalvular atrial fibrillation (NVAF) patients treated with dabigatran remains unclear. This study aimed to explore the association between leukocyte count and bleeding events after excluding other confounders in NVAF patients taking dabigatran.@*Methods@#A total of 851 NVAF patients treated with dabigatran (110 mg bid) were recruited from 12 centers in China from February 2015 to December 2017. Follow-up was completed by May 2018. The exposure and outcome variables were leukocyte count measured at baseline and the number of bleeding events within the subsequent 6 months. Multivariate Cox proportional hazards models were constructed to analyze independent associations, and a Cox proportional hazards regression with cubic spline functions and smooth curve fitting (penalized spline method) was used to address nonlinearity between leukocyte count and bleeding. The inflection point was calculated using a recursive algorithm, and then a two-piecewise Cox proportional hazards model for both sides of the inflection point was constructed.@*Results@#During 6-month follow-up, 87 participants occurred bleeding events. For every 1 × 109/L increase in leukocyte count, the risk of bleeding increased by 11% (hazard ratio [HR]: 1.11, 95% confidence interval [CI]: 0.99–1.25). The smooth curve showed nonlinear relationship between leukocyte count and bleeding events. The inflection point of the leukocyte count was 6.75 × 109/L. For leukocyte counts < 6.75 × 109/L, the HR (95% CI) was 0.88 (0.69–1.13), and for leukocyte counts ≥ 6.75 × 109/L, the HR (95% CI) was 1.28 (1.09–1.51).@*Conclusion@#This study found a J-shaped association between baseline leukocyte count and risk of bleeding in NVAF patients treated with dabigatran.@*Clinical trial registration@#NCT02414035, https://clinicaltrials.gov.

Low deceleration capacity is associated with higher stroke risk in patients with paroxysmal atrial fibrillation / 中华医学杂志(英文版)

Background@#Deceleration capacity (DC) is a non-invasive marker for cardiac autonomic dysfunction; however, few studies have shown that the influence factors of cardiac autonomic dysfunction and the correlations between DC and stroke risk in paroxysmal atrial fibrillation (AF). We aimed to explore the influencing factors of abnormal DC and the relationships between DC and stroke risk in patients with paroxysmal AF.@*Methods@#The study included hospitalized paroxysmal AF patients with DC measurements derived from 24-h Holter electrocardiography recordings taken between August 2015 and June 2016. Multivariable regression analysis was performed to evaluate the associations between correlated variables and abnormal DC values. The relationship between DC and ischemic stroke risk scores in patients with paroxysmal AF was analyzed.@*Results@#We studied 259 hospitalized patients with paroxysmal AF (143 [55.2%] male, mean age 66.4 ± 12.0 years); 38 patients of them showed abnormal DC values. In the univariate analysis, age, hypertension, heart failure, and previous stroke/transient ischemic attack (TIA) were significantly associated with abnormal DC values. Among these factors, a history of previous stroke/TIA (odds ratio = 2.861, 95% confidence interval: 1.356–6.039) were independently associated with abnormal DC values in patients with paroxysmal AF. The abnormal DC group showed a higher stroke risk with the score of congestive heart failure, hypertension, age >75 years, diabetes mellitus, previous stroke and TIA (CHADS2) (2.25 ± 1.48 vs. 1.40 ± 1.34, t = -4.907, P = 0.001) and CHA2DS2-vascular disease, age 65–74 years and female category (VASc) (3.76 ± 1.95 vs. 2.71 ± 1.87, t = -4.847, P = 0.001) scores. Correlation analysis showed that DC was negatively correlated with CHADS2 scores (r = -0.290, P < 0.001) and CHA2DS2-VASc scores (r = -0.263, P > 0.001).@*Conclusions@#Lower DC is closely associated with previous stroke/TIA, and is also correlated negatively with higher stroke risk scores in patients with paroxysmal AF. It could be a potential indicator of stroke risk in paroxysmal AF patients.

Mitochondrial fusion-fission and heart failure / 基础医学与临床

Mitochondrial fusion,fission and dynamic transformation between the two are commonly known as mito-chondrial dynamics. Mitochondrial fusion-fission is related to a variety of biological functions of mitochondria inclu-ding regulation of energy metabolism, production of reactive oxygen species, maintenance of Ca2+homeostasis and influence of cellular death. Cardiac development,energy metabolism and ion homeostasis are closely related to the balance of mitochondrial fusion-fission.Mitochondrial fusion-fission disorders may cause myocardial cell dysfunction, damage and even the death of myocardial cells,which result in heart failure ultimately. Developing medicines tar-getting to reconstruct the balance of mitochondrial fusion-fission may provide new ideas and strategies for the treat-ment of chronic heart failure.

Rapamycin protects cardiomyocytes against anoxia/reoxygenation injury by inducing autophagy through the PI3k/Akt pathway / 华中科技大学学报（医学）（英德文版）

The purpose of this study was to investigate the potential cardioprotection roles of Rapamycin in anoxia/reoxygenation (A/R) injury of cardiomyocytes through inducing autophagy, and the involvement of PI3k/Akt pathway. We employed simulated A/R of neonatal rat ventricular myocytes (NRVM) as an in vitro model of ischemial/reperfusion (I/R) injury to the heart. NRVM were pretreated with four different concentrations of Rapamycin (20, 50, 100, 150 μmol/L), and pretreated with 10 mmol/L 3-methyladenine (3MA) for inhibiting autophagy during A/R. Then, Western blot analysis was used to examine variation in the expression of LC3-II, LC3-I, Bim, caspase-3, p-PI3KI, PI3KI, p-Akt and Akt. In our model, Rapamycin had a preferential action on autophagy, increasing the expression of LC3-II/LC3-I, whereas decreasing the expression of Bim and caspase-3. Moreover, our results also demonstrated that Rapamycin inhibited the activation of p-PI3KI and enhanced the activation of p-Akt. It is concluded that Rapamycin has a cardioprotection effect by inducing autophagy in a concentration-dependent manner against apopotosis through PI3K/Akt signaling pathway during A/R in NRVM.

Rapamycin protects cardiomyocytes against anoxia/reoxygenation injury by inducing autophagy through the PI3k/Akt pathway / 华中科技大学学报（医学）（英德文版）

The purpose of this study was to investigate the potential cardioprotection roles of Rapamycin in anoxia/reoxygenation (A/R) injury of cardiomyocytes through inducing autophagy, and the involvement of PI3k/Akt pathway. We employed simulated A/R of neonatal rat ventricular myocytes (NRVM) as an in vitro model of ischemial/reperfusion (I/R) injury to the heart. NRVM were pretreated with four different concentrations of Rapamycin (20, 50, 100, 150 μmol/L), and pretreated with 10 mmol/L 3-methyladenine (3MA) for inhibiting autophagy during A/R. Then, Western blot analysis was used to examine variation in the expression of LC3-II, LC3-I, Bim, caspase-3, p-PI3KI, PI3KI, p-Akt and Akt. In our model, Rapamycin had a preferential action on autophagy, increasing the expression of LC3-II/LC3-I, whereas decreasing the expression of Bim and caspase-3. Moreover, our results also demonstrated that Rapamycin inhibited the activation of p-PI3KI and enhanced the activation of p-Akt. It is concluded that Rapamycin has a cardioprotection effect by inducing autophagy in a concentration-dependent manner against apopotosis through PI3K/Akt signaling pathway during A/R in NRVM.

Selective beta-1 blockers deteriorate glucose metabolism. A meta-analysis

To provide an up-to-date synthesis of available data, and to quantify the effect of highly selective beta-1 blockers on glucose metabolism in patients with essential hypertension and type 2 diabetes mellitus [T2DM] by using pooled analysis techniques. Cochrane Library, PubMed, MEDLINE, and EMBASE databases were searched from inception to July 2013 in the Third Affiliated Hospital of Nanchang University, Nanchang, China. We collected randomized controlled trails reporting on the effect of highly selective beta-1 blockers on glucose metabolism in patients with hypertension and type 2 diabetes. Data was screened, evaluated, and extracted by 2 independent researchers according to the inclusion and exclusion criteria. Meta-analysis was conducted using RevMan5.0 software. Seven trials were enrolled in the meta-analysis including a total of 1354 patients. Meta-analysis results revealed that when compared with the control group, selective beta-1 blockers were associated with a higher fasting blood glucose [weighed mean difference: 0.21, 95% confidence interval [CI]: 0.16-0.27; p<0.00001]. But results revealed no significant difference in glycosylated hemoglobin [weighed mean difference: 0.13, 95% CI: -0.11 to 0.37; p=0.28], fasting insulin [weighed mean difference: -1.13, 95% CI: -4.27 to 2.01; p=0.48], and gain in body weight [weighed mean difference: 1, 95% CI: -1.08 to 3.08; p=0.35]. Selective beta-1 blockers were associated with elevated fasting blood glucose. Thus, it should not be used for patients with essential hypertension and diabetes

SCN5A mutation in patients with Brugada electrocardiographic pattern induced by fever / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the relationship between SCN5A, SCN1b, SCN3b and GPD1L genotypes and the risk of malignant arrhythmia in patients with Brugada electrocardiographic pattern induced by fever.</p><p><b>METHODS</b>The clinical data and peripheral blood of patients with Brugada electrocardiographic pattern induced by fever were collected. Patients with depolarization abnormality associated with hypertension, coronary heart disease, drugs and other factors were excluded. The direct DNA sequencing was used to screen the mutation of candidate gene SCN5A, SCN1b, SCN3b and GPD1L. If gene variation was found, mutation or polymorphism was then determined by comparison with 200 control individuals. The relationship between genotype and phenotype as well as the risk of malignant arrhythmia were analyzed.</p><p><b>RESULTS</b>Five eligible patients with fever-induced Brugada ECG pattern were included in this study. TypeI Brugada ECG was presented in all five patients in fibrile state and disappeared in normothermia. No sudden cardiac death (SCD) occurred and no ventricular arrhythmia was presented in Holter monitor during the 3 to 5 years follow-up period. Six gene variants were found including a novel missense mutation of base C to T, named Arg965 Cys (R965C), which located in 965 codon of the 17 exon in SCN5A, and five SCN5A polymorphisms including A29A (c.87A>G), R1193Q (c.3578G>A), D1819D (c.5457T>C), exon11 -24G>A, exon23 +4A>G.</p><p><b>CONCLUSION</b>SCN5A mutation is related to fever-induced Brugada ECG pattern. However, individuals with Brugada ECG pattern induced by fever bear low risk of malignant arrhythmia and SCD during fibrile state and follow up in this small patient cohort.</p>

Effect of hypoxia inducible factor-1α on thermotolerance against hyperthemia induced cardiomyocytes apoptosis / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the expression changes and effects of hypoxia inducible factor-1α (HIF-1α) on non-lethal high temperature induced thermotolerance and its role on thermotolerance protection.</p><p><b>METHODS</b>H9c2 cardiomyocytes were cultured and pretreated with the HIF-1α inhibitor YC-1, the cells were then subjected to normal temperature (37 °C), thermotolerance induction (40 °C, 3 h), or hyperthermia (43 °C, 2 h). The cells were divided into 8 groups (n = 3 each): normal temperature control group; thermotolerance group; thermotolerance/hyperthermia group; hyperthermia group; DMSO+normal temperature group; YC-1+thermotolerance group; YC-1+thermotolerance/hyperthermia group; YC-1+hyperthermia group. Cell apoptotic rate was assessed by flow cytometry. Western blot was used to detect the expression of HIF-1α and caspase-3.</p><p><b>RESULTS</b>Flow cytometry results showed that apoptosis rate was similar between control group and thermotolerance group, between DMSO+normal temperature group and YC-1+thermotolerance group, between YC-1+thermotolerance/hyperthermia group and YC-1+hyperthermia group, but was significantly higher in hyperthermia group [(17.35 ± 1.07)%] than in control group [(7.52 ± 1.55)%, P < 0.01] which was partly reduced in thermotolerance/hyperthermia group [(12.58 ± 1.97)%, P < 0.01 vs. thermotolerance group]. Cell apoptosis rate of YC-1+thermotolerance/hyperthermia group (23.75 ± 1.92)% was significantly higher than that of thermotolerance/hyperthermia group [(12.58 ± 1.97)%, P < 0.01], and in YC-1+hyperthermia group [(24.89 ± 1.83)%] than in hyperthermia group [(17.35 ± 1.07)%, P < 0.01]. HIF-1α expression was obviously upregulated in thermotolerance cells compared with control cells, in thermotolerance/hyperthermia cells than in hyperthermia cells, in YC-1+thermotolerance group, YC-1+thermotolerance/hyperthermia group and YC-1+hyperthermia group than in DMSO group (all P < 0.05). Caspase-3 expression was similar between control group and thermotolerance group, but was significantly lower in thermotolerance/hyperthermia group than in hyperthermia group (P < 0.05), significantly higher in YC-1+thermotolerance group, YC-1+thermotolerance/hyperthermia group and YC-1+hyperthermia group than in DMSO group (all P < 0.05) and significantly higher in YC-1+thermotolerance/hyperthermia group than in thermotolerance/hyperthermia group (P < 0.01) and in YC-1+hyperthermia group than in hyperthermia group (P < 0.01).</p><p><b>CONCLUSION</b>Non-lethal high temperature induced thermotolerance can reduce heat stress-induced cardiomyocytes apoptosis rate via upregulating the expression of HIF-1α and inhibiting caspase-3 signalling pathways.</p>

Remote postconditioning induced by brief pulmonary ischemia and reperfusion attenuates myocardial reperfusion injury in rabbits / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The lung is one of the most important organs that are sensitive to ischemia. We hypothesized that remote postconditioning (RPostC) induced by brief occlusion and reperfusion of the pulmonary artery could attenuate myocardial reperfusion injury.</p><p><b>METHODS</b>Thirty rabbits were randomized into three groups. Group ischemia-reperfusion (IR) (n = 10) were anesthetized rabbits subjected to 30-minute occlusion of the left anterior descending coronary artery followed by 180-minute reperfusion. Group RPostC (n = 10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion, and the left anterior descending coronary artery (LAD) occluded for 30 minutes with a 180-minute reperfusion. Group L-N(w)-nitro-L-arginine methylester (L-NAME) + RPostC (n = 10) had the left pulmonary artery blocked for five minutes followed by a 5-minute reperfusion and intravenous infusion of L-NAME (10 mg/kg), and the LAD occluded for 30 minutes with a 180-minute reperfusion. Blood samples were taken for levels of creatine kinase (CK), superoxide dismutase (SOD) and malondialdehyde (MDA) at three different time points. At the end of the experiment, tissue samples of the infarcted region were harvested to calculate the cardiomyocyte apoptosis index (AI) by TUNEL. A piece of left and right lung tissue was harvested to evaluate the damage to the lung.</p><p><b>RESULTS</b>After reperfusion for 180 minutes, the concentration of CK was lower in group RPostC, (4.79 ± 0.27) U/ml, than that in group IR, (6.23 ± 0.55) U/ml (P < 0.01), and group L-NAME + RPsotC, (5.86 ± 0.42) U/ml (P < 0.01). The concentration of MDA was lower in group RPostC, (6.06 ± 0.36) nmol/ml, than that in group IR, (11.41 ± 0.91) nmol/ml (P < 0.01), and group L-NAME + RPostC, (11.06 ± 0.62) nmol/ml (P < 0.01). The activity of SOD was higher in group RPostC, (242.34 ± 25.02) U/ml, than that in group IR, (148.05 ± 18.24) U/ml (P < 0.01), and group L-NAME + RPostC, (160.66 ± 9.55) U/ml (P < 0.01). The apoptosis index was lower in group RPostC, (14.25 ± 5.20)%, than that in group IR, (35.77 ± 10.09)% (P < 0.01), and group L-NAME + RPostC, (30.37 ± 7.76)% (P < 0.01). No significant difference caused by pulmonary ischemia was found in the lung tissue among the three groups.</p><p><b>CONCLUSIONS</b>RPostC may attenuate myocardial ischemia-reperfusion injury connected to the activity of endothelial nitric oxide synthase. Brief pulmonary ischemia may not be harmful to lungs.</p>

The protection of heme oxygenase-1 from acute cardiocyte injury in rats / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the protection of Heme oxygenase-1 (HO-1) from lipopolysaccharide (LPS)-induced cardiocyte injury and its mechanism.</p><p><b>METHODS</b>Cardiocyte was isolated from SD neonate rat and cultured in vitro, and was divided into control group (normal culture), LPS group (with stimulation of 30 micromoL/L LPS for 1 hour), LPS + Hemin group (with same treatment to LPS group after stimulation of 5 micromoL/L Hemin for 1 hour), and LPS + ZnPP group (with same treatment to LPS group after stimulation of 3 micromoL/L ZnPP for 1 hour). The level of lactic-dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD) were measured by thio-barbituric acid and xanthine oxidase techniques. The cell heart rhythm, survival rate and apoptosis rate were examined. The expressions of nuclear factor kappaB (NF-kappaB), HO-1 and tumor necrosis factor-alpha (TNF-alpha) were measured with Western blotting. The HO-1 mRNA was examined by RT-PCR.</p><p><b>RESULTS</b>The level of LDH and MDA in LPS, LPS + Hemin, and LPS + ZnPP groups were (113 +/- 15), (79 +/- 13), (154 +/- 22) U/L, and (1.88 +/- 0.36), (1.16 +/- 0.32), (2.84 +/- 0.44) mmoL/L respectively, which were all obviously higher than those in control group [(69 +/- 10) U/L, (0.87 +/- 0.25) mmol/L, P < 0.05]. The level of SOD in LPS, PS + Hemin, and LPS + ZnPP groups (17.8 +/- 1.8, 22.5 +/- 2.4, 13.4 +/- 1.5 U/mL, respectively) was all obviously lower than that in control group (24.3 +/- 3.6 U/mL, P < 0.05). The apoptosis rate and heart rhythm were obviously higher and survival rate significantly lower in LPS, LPS + Hemin, and LPS + ZnPP groups than those in control group (P < 0.05). The level of HO-1mRNA in LPS, LPS + Hemin, and LPS + ZnPP groups was higher than that in control group (P < 0.01), among which LPS + Hemin group was the highest. The level of HO-1, TNF-alpha and NF-kappaB in LPS, LPS + Hemin, and LPS + ZnPP groups was higher than those in control group (P < 0.05), among which the level of HO-1 protein in LPS + Hemin group was the highest, the level of TNF-alpha and NF-kappaB in LPS + ZnPP group was highest.</p><p><b>CONCLUSION</b>LPS can induce cardiocyte injury, which can be inhibited through the anti-inflammatory, anti-oxidant, and anti-apoptosis functions by HO-1.</p>

Same genotype and different phenotypes in a family with PRKAG2 gene mutation / 中华心血管病杂志

<p><b>OBJECTIVE</b>The gamma(2) subunit of AMP-activated protein kinase (PRKAG2) located in chromosome 7 plays an important role in regulating metabolic pathways, and patients with PRKAG2 mutations are associated with familial ventricular pre-excitation, hypertrophic cardiomyopathy and AV block. We observed the difference on the phenotypes in a large family with same PRKAG2 mutation.</p><p><b>METHOD</b>Direct DNA sequence was performed to screen the exons and exon-intron boundaries of PRKAG2 gene in a large family with 13 affected persons detected by electrocardiography (ECG).</p><p><b>RESULTS</b>Sinus bradycardia, short PR interval, right bundle bunch block (RBBB), complete AV block, atrial flutter, atrial fibrillation and sudden cardiac death were identified in this family. Hypertrophic cardiomyopathy was found in one family member. Genetic analysis revealed a missense mutation (Arg302Glu) in all affected family members. This mutation was previous described in patients with Wolff-Parkinson-White (WPW) syndrome and hypertrophic cardiomyopathy.</p><p><b>CONCLUSIONS</b>Besides WPW syndrome and hypertrophic cardiomyopathy, PRKAG2 mutations are responsible also for a diverse phenotypes. PRKAG2 gene mutation should be suspected with familial occurrence of RBBB, sinus bradycardia, and short PR interval.</p>

Heat shock protein 70 gene transfection protects rat myocardium cell against anoxia-reoxygeneration injury / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>A number of studies suggest that the expression of heat shock protein 70 (HSP(70)) induced by heat stress are associated with protection against ischemia-reperfusion injury. But the protective effects may be contaminated by other factors in the same stress. This study was conducted to explore the protective role of HSP(70) expression in acute myocardial anoxia/reoxygeneration (A/R) injury with a liposome-mediated gene transfer technique for the introduction of pCDNA HSP(70) into the neonatal rat myocardial cells. In addition, heat shock stress cytoprotection was also investigated for comparison.</p><p><b>METHODS</b>The cultured primary neonatal rat myocardiocytes with an acute myocardial A/R injury model and the HS-treated rat myocardiocyte model were used. Three-day cultured myocardiocytes were randomly divided into four groups (n = 8): control group, A/R group, HS + A/R group and pCDNA HSP(70) + A/R group. A liposome-coated HSP(70) pCDNA plasmid was transfected into the primary neonatal rat myocardiocytes; HSP(70) mRNA and its protein were confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. The cell viability was assayed by monotetrazolium (MTT) and the lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activity of cells during incubation and the changes in cells ultrastructure were examined. NF-kappaB activity in the primary neonatal rat myocardiocytes was measured with flow cytometry.</p><p><b>RESULTS</b>Compared with viability in the A/R group ((35.4 +/- 6.9)%) the cell viability in the HS + A/R group ((72.8 +/- 11.6)%) and the pCDNA HSP(70) + A/R group ((76.3 +/- 12.2)%) was improved significantly (P < 0.05). The activity of LDH and CPK was significantly elevated in the A/R group. However, in the HS + A/R group and pCDNA HSP(70) + A/R group, significant decreases in activity were observed. The cell ultrastructure of the A/R group cells was abnormal, whereas nearly normal ultrastructure was observed in HS + A/R group and pCDNA HSP(70) + A/R group. HSP(70) mRNA and protein were slightly expressed in the myocardiocytes of the A/R group. However, obvious overexpression was observed in the HS + A/R group and in the pCDNA HSP(70) + A/R group (P < 0.01). And there was a significant difference between the HS + A/R group and the pCDNA HSP(70) + A/R group in the expression of HSP(70) mRNA and protein (P < 0.01). A high activity of NF-kappaB (5.76 +/- 0.64) was detected in the A/R group. But in the HS + A/R group there was a statistically significant decrease in the activity of NF-kappaB compared with the A/R group (3.11 +/- 0.52 vs 5.76 +/- 0.64, P < 0.01). The same statistically significant difference was also observed in the pCDNA HSP(70) + A/R group and A/R group (2.83 +/- 0.49 vs 5.76 +/- 0.64, P < 0.01).</p><p><b>CONCLUSIONS</b>Overexpression of HSP(70) alone by gene transfection leads to protection for cardiac myocyte against anoxia-reoxygeneration. These cardioprotective effects were related to the reduction in activation of NF-kappaB.</p>

The Protective Role of Ebselen and VitE on Hypertensive Heart Damage in NO-deficient Rats / 中华高血压杂志

Background Chronic administration with inhibitor of nitric oxide synthase (N_?-nitro-L-arginine methyl ester,L-NAME) induces persistent hypertension,cardiovascular remodeling,surrounding vascular fibrosis, necrosis and hypertrophy of myocardium,and inflammation in cardiovascular system.Local RAS involves in hyper- tension and remodeling of cardiovascular system,via increasing production of oxygen free radicals (OFR).Objec- tive To elucidate the preventive and therapeutic effect of antioxidant Ebselen and/or VitE on hypertensive heart damage in NO~- deficient rats induced by L-NAME.Methods Thirty-two Wistar rats were administered with L- NAME 50 mg/(kg?d) by gavage for 8 weeks,and randomized to received a placebo(L),or Ebs(S,30 mg/kg?d), or VitE(V,40 mg/kg?d) or Ebs 30 mg/(kg?d)+VitE 40 mg/(kg?d),with 8 normal Wistar as control. Body mass and SBP were measured fortnightly.Plasma and homogenate of heart were collected for NO,Ang Ⅱ, GSH-PX,MDA and O_2~- determination.Results Eight weeks after L-NAME administration,SBP in experimental groups was obviously higher than that of control (P

Characteristics of Electrocardiography in Pressure Overload-induced Cardiac Hypertrophy Rats / 中华高血压杂志

Objective To analyze the electrocardiography(ECG)data of pressure overload-induced cardiac hy pertrophy rats.Methods Pressure overload cardiac hypertrophy was induced by abdominal aorta constriction. Echocardiogram and heart weight measurement demonstrated the occurrence of cardiac hypertrophy.Standardized ECG parameters of limb and chest were measured and statistically analyzed.Results Two weeks after hypertrophy models were established,echocardiogram showed greater LVPWTd,IVSTd,LVDd.ECG showed that left axis deviation and higher R waves in V_A,V_B,V_C(P