The role and mechanisms of microvascular damage in the ischemic myocardium.

Following myocardial ischemic injury, the most effective clinical intervention is timely restoration of blood perfusion to ischemic but viable myocardium to reduce irreversible myocardial necrosis, limit infarct size, and prevent cardiac insufficiency. However, reperfusion itself may exacerbate cell death and myocardial injury, a process commonly referred to as ischemia/reperfusion (I/R) injury, which primarily involves cardiomyocytes and cardiac microvascular endothelial cells (CMECs) and is characterized by myocardial stunning, microvascular damage (MVD), reperfusion arrhythmia, and lethal reperfusion injury. MVD caused by I/R has been a neglected problem compared to myocardial injury. Clinically, the incidence of microvascular angina and/or no-reflow due to ineffective coronary perfusion accounts for 5-50% in patients after acute revascularization. MVD limiting drug diffusion into injured myocardium, is strongly associated with the development of heart failure. CMECs account for > 60% of the cardiac cellular components, and their role in myocardial I/R injury cannot be ignored. There are many studies on microvascular obstruction, but few studies on microvascular leakage, which may be mainly due to the lack of corresponding detection methods. In this review, we summarize the clinical manifestations, related mechanisms of MVD during myocardial I/R, laboratory and clinical examination means, as well as the research progress on potential therapies for MVD in recent years. Better understanding the characteristics and risk factors of MVD in patients after hemodynamic reconstruction is of great significance for managing MVD, preventing heart failure and improving patient prognosis.

A prediction model to predict in-hospital mortality in patients with acute type B aortic dissection.

BACKGROUND: Acute type B aortic dissection (ABAD) is a life-threatening cardiovascular disease. A practicable and effective prediction model to predict and evaluate the risk of in-hospital death for ABAD is required. The present study aimed to construct a prediction model to predict the risk of in-hospital death in ABAD patients. METHODS: A total of 715 patients with ABAD were recruited in the first affiliated hospital of Xinjiang medical university from April 2012 to May 2021. The information on the demographic and clinical characteristics of all subjects was collected. The logistic regression analysis, receiver operating characteristic (ROC) curve analysis, and nomogram were applied to screen the appropriate predictors and to establish a prediction model for the risk of in-hospital mortality in ABAD. The receiver operator characteristic curve and calibration plot were applied to validate the performance of the prediction model. RESULTS: Of 53 (7.41%) subjects occurred in-hospital death in 715 ABAD patients. The variables including diastolic blood pressure (DBP), platelets, heart rate, neutrophil-lymphocyte ratio, D-dimer, C-reactive protein (CRP), white blood cell (WBC), hemoglobin, lactate dehydrogenase (LDH), procalcitonin, and left ventricular ejection fraction (LVEF) were shown a significant difference between the in-hospital death group and the in-hospital survival group (all P < 0.05). Furthermore, all these factors which existed differences, except CRP, were associated with in-hospital deaths in ABAD patients (all P < 0.05). Then, parameters containing LVEF, WBC, hemoglobin, LDH, and procalcitonin were identified as independent risk factors for in-hospital deaths in ABAD patients by adjusting compound variables (all P < 0.05). In addition, these independent factors were qualified as predictors to build a prediction model (AUC > 0.5, P < 0.05). The prediction model was shown a favorable discriminative ability (C index = 0.745) and demonstrated good consistency. CONCLUSIONS: The novel prediction model combined with WBC, hemoglobin, LDH, procalcitonin, and LVEF, was a practicable and valuable tool to predict in-hospital deaths in ABAD patients.

A prediction model based on platelet parameters, lipid levels, and angiographic characteristics to predict in-stent restenosis in coronary artery disease patients implanted with drug-eluting stents.

BACKGROUND: The present study was aimed to establish a prediction model for in-stent restenosis (ISR) in subjects who had undergone percutaneous coronary intervention (PCI) with drug-eluting stents (DESs). MATERIALS AND METHODS: A retrospective cohort study was conducted. From September 2010 to September 2013, we included 968 subjects who had received coronary follow-up angiography after primary PCI. The logistic regression analysis, receiver operator characteristic (ROC) analysis, nomogram analysis, Hosmer-Lemeshow χ2 statistic, and calibration curve were applied to build and evaluate the prediction model. RESULTS: Fifty-six patients (5.79%) occurred ISR. The platelet distribution width (PDW), total cholesterol (TC), systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), and lesion vessels had significant differences between ISR and non-ISR groups (all P < 0.05). And these variables were independently associated with ISR (all P < 0.05). Furthermore, they were identified as predictors (all AUC > 0.5 and P < 0.05) to establish a prediction model. The prediction model showed a good value of area under curve (AUC) (95%CI): 0.72 (0.64-0.80), and its optimized cut-off was 6.39 with 71% sensitivity and 65% specificity to predict ISR. CONCLUSION: The incidence of ISR is 5.79% in CAD patients with DES implantation in the Xinjiang population, China. The prediction model based on PDW, SBP, TC, LDL-C, and lesion vessels was an effective model to predict ISR in CAD patients with DESs implantation.

Overexpression of IκBα in cardiomyocytes alleviates hydrogen peroxide-induced apoptosis and autophagy by inhibiting NF-κB activation.

BACKGROUND: Inflammation and oxidative stress play predominant roles in the initiation and progression of ischaemia/reperfusion (I/R) injury, with nuclear factor kappa B (NF-κB) serving as a crucial mediator. Overexpression of the inhibitor of κB alpha (IκBα) gene is hypothesized to have protective effects against apoptosis and autophagy in cardiomyocytes subjected to hydrogen peroxide (H2O2) by inhibiting the NF-κB pathway. METHODS: The IκBαS32A, S36A gene was transfected via adeno-associated virus serotype 9 (AAV9) delivery into neonatal rat ventricular cardiomyocytes (NRVMs) prior to H2O2 treatment. NRVMs were divided into control, H2O2, GFP + H2O2, IκBα+H2O2, and pyrrolidine dithiocarbamate (PDTC) + H2O2 groups. Nuclear translocation of the NF-κB p65 subunit was evaluated by immunofluorescence and Western blotting. Cell viability was assessed by Cell Counting Kit-8 assay. Supernatant lactate dehydrogenase (LDH) and intracellular malondialdehyde (MDA) were measured to identify H2O2-stimulated cytotoxicity. Apoptosis was determined by Annexin V-PE/7-AAD staining, and the mitochondrial membrane potential (ΔΨm) was detected by JC-1 staining. Western blotting was used to detect apoptosis- and autophagy-related proteins. RESULTS: IκBα transfection significantly increased cell viability and ΔΨm but decreased the supernatant LDH and cellular MDA levels in cardiomyocytes exposed to H2O2. Meanwhile, IκBα overexpression decreased H2O2-induced apoptosis by upregulating the Bcl-2/Bax ratio and reduced autophagy by downregulating the expression of Beclin-1 and the LC3-II/LC3-I ratio. These effects partly accounted for the ability of IκBα to inhibit the NF-κB signalling pathway, as evidenced by decreases in p65 phosphorylation and nuclear translocation. Indeed, the effects of inactivation of NF-κB signalling with the specific inhibitor PDTC resembled the cardioprotective effects of IκBα during H2O2 stimulation. CONCLUSION: IκBα overexpression can ameliorate H2O2-induced apoptosis, autophagy, oxidative injury, and ΔΨm loss through inhibition of the NF-κB signalling pathway. These findings suggest that IκBα transfection can result in successful resistance to oxidative stress-induced damage by inhibiting NF-κB activation, which may provide a potential therapeutic target for the prevention of myocardial I/R injury.

Cardioprotective effects of constitutively active MEK1 against H2O2-induced apoptosis and autophagy in cardiomyocytes via the ERK1/2 signaling pathway.

Oxidative stress injury is one of the main mechanisms of ischemia-reperfusion (I/R) injury. The extracellular signal-regulated kinase (ERK1/2) pathway plays an important role in cardioprotective during acute myocardial infarction. In this study, we used constitutively active MEK1 gene (CaMEK) transfection strategy to investigate whether CaMEK provides a protective effect against apoptosis and autophagy induced by Hydrogen peroxide (H2O2) in neonatal rat cardiac ventricular cardiomyocytes (NCMs) and the underlying mechanisms. As a result, CaMEK attenuated H2O2-induced apoptosis and cytotoxicity in NCMs, evidenced by decreased apoptotic cells and the ratio of Bax/Bcl-2, increased the mitochondrial membrane potential (Δψm) and cell vitality and reduced the level of lactate dehydrogenase (LDH). Further studies revealed that CaMEK attenuated H2O2-induced autophagy, evidenced by the decreased LC3-Ⅱ/LC3-Ⅰratio and SQSTM1/p62 (p62) degradation. Furthermore, we demonstrated that CaMEK phosphorylated the ERK1/2 pathway-related proteins, ERK1/2, p70S6K and GSK3ß, in NCMs with H2O2 stimulation. In contrast, these effects could be reversed by co-treatment with the ERK1/2 inhibitor, PD98059. These results suggest that CaMEK plays an important role in protecting cardiomyocytes against H2O2-induced injury and autophagy in NCMs via ERK1/2 pathway. Therefore, transfection of CaMEK may provide a hopeful therapeutic strategy for I/R.

Macrophage migration inhibitory factor plays an essential role in ischemic preconditioning-mediated cardioprotection.

Ischemic preconditioning (IPC) is an endogenous protection strategy against myocardial ischemia-reperfusion (I/R) injury. Macrophage migration inhibitory factor (MIF) released from the myocardium subjected to brief periods of ischemia confers cardioprotection. We hypothesized that MIF plays an essential role in IPC-induced cardioprotection. I/R was induced either ex vivo or in vivo in male wild-type (WT) and MIF knockout (MIFKO) mice with or without proceeding IPC (three cycles of 5-min ischemia and 5-min reperfusion). Indices of myocardial injury, regional inflammation and cardiac function were determined to evaluate the extent of I/R injury. Activations of the reperfusion injury salvage kinase (RISK) pathway, AMP-activated protein kinase (AMPK) and their downstream components were investigated to explore the underlying mechanisms. IPC conferred prominent protection in WT hearts evidenced by reduced infarct size (by 33-35%), myocyte apoptosis and enzymatic markers of tissue injury, ROS production, inflammatory cell infiltration and MCP1/CCR2 expression (all P<0.05). IPC also ameliorated cardiac dysfunction both ex vivo and in vivo These protective effects were abolished in MIFKO hearts. Notably, IPC mediated further activations of RISK pathway, AMPK and the membrane translocation of GLUT4 in WT hearts. Deletion of MIF blunted these changes in response to IPC, which is the likely basis for the absence of protective effects of IPC against I/R injury. In conclusion, MIF plays a critical role in IPC-mediated cardioprotection under ischemic stress by activating RISK signaling pathway and AMPK. These results provide an insight for developing a novel therapeutic strategy that target MIF to protect ischemic hearts.

Apolipoprotein A1 is associated with SYNTAX score in patients with a non-ST segment elevation myocardial infarction.

BACKGROUND: The study was designed to investigate lipid profile and SYNTAX score in patients with non-ST segment elevation myocardial infarction (NSTEMI). METHODS: 311 patients with NSTEMI were enrolled. The demographic, clinical data, blood samples and SYNTAX score were documented. The Pearson linear correlation was used to detect confounding factors linearly correlated with SYNTAX score. The significantly correlated confounding factors were put into the multiple linear regressions. RESULTS: The Pearson linear correlation showed that high-density lipoprotein- cholesterol (HDL-C) and apolipoprotein A1 (ApoA1) were significantly correlated with Syntax Score (r = - 0.119, P = 0.044 and r = - 0.182, P = 0.002, respectively). The multiple linear regressions for Syntax Score were built using HDL-C and ApoA1, respectively. After the adjustment of other significantly correlated confounding factors such as white blood cell count (WBC), myohemoglobin (MB), glutamic-oxalacetic transaminase (AST) and creatinine, the ApoA1 still showed significant association with Syntax Score (ß = - 0.151, P = 0.028). The area under curve was (AUC) 0.624 and the optimal cutoff value is 1.07 g/L when using ApoA1 to predict moderate and severe coronary artery lesions. The patients with ApoA1 ≥ 1.07 g/L and < 1.07 g/L have the Syntax Scores of 12.21 ± 11.58 and 16.33 ± 11.53, respectively (P = 0.001). CONCLUSIONS: The ApoA1 is the only lipid factor significantly associated with complexity of coronary artery lesion in patients with NSTEMI, the patients with ApoA1 < 1.07 g/L may have more complex coronary artery lesions.

Targeting transgene to the heart and liver with AAV9 by different promoters.

Adeno-associated virus (AAV) has become one of the most promising gene transfer tools for gene therapy. This work aims to evaluate tropism, gene transfer efficiency and safety of AAV9 vectors produced with recombinant baculovirus (rBac)-based system. AAV9-CMV-GFP and AAV9-CBA-GFP were produced using a rBac system, 1 × 10(11) particles of each vectors were administered intravenously (i.v.) into mice and animals were killed at 1, 2, 3, 4, 5 and 8 weeks after administration. The GFP expression in different organs was analyzed by fluorescence imaging and Western blot. Viral genomic quantities were measured using qPCR. In vitro transduction efficiency of AAV9 vectors in primary cardiomyocytes and hepatocytes was determined by flow cytometry. Toxicity of AAV9 vectors was evaluated by determining certain cardiac and liver injury biomarkers and renal function test in vivo and TUNEL analysis in vitro. The data showed that AAV9 viral particles packaged by the rBac system were fully functional in vivo and in vitro. The CMV promoter predominantly induced higher cardiac GFP transgene expression and DNA copy numbers while the CBA promoter resulted in robust GFP expression and high vector DNA copy numbers in mouse liver, both in a time-dependent increased manner. Such distinct preferential effects were also observed in the heart and liver as early as 3 and 5 days after co-infection. Both the AAV9-CMV and AAV9-CBA viral packages did not induce heart, liver and renal damage and cell apoptosis. These results indicated that AAV9-CMV can efficiently and safely direct cardiac gene transfer, whereas AAV9-CBA is preferential for liver gene delivery.

Relationship between CYP17A1 genetic polymorphism and coronary artery disease in a Chinese Han population.

BACKGROUND: CYP17A1 gene encodes P450c17 proteins, which is a key enzyme that catalyzes the formation of sex hormones. Many clinical studies showed that sex hormones levels play an important role in the pathogenesis of coronary artery disease (CAD). However, the relationship between CYP17A1 genetic polymorphisms and CAD remains unclear. The aim of this study was to investigate the association of CYP17A1 genetic polymorphisms with CAD in a Han population of China. METHODS: A total of 997 people include 490 patients and 507 controls were selected for the present study. Five single-nucleotide polymorphisms (SNPs) (rs4919686, rs1004467, rs4919687, rs10786712, and rs2486758) were genotyped by using the real-time PCR (TaqMan) method. RESULTS: For men, the rs10786712 was found to be associated with CAD in a recessive model (P=0.016), after adjustment of the major confounding factors, the significant difference was retained (OR=1.644, 95% confidence interval [CI]: 1.087-2.488, P=0.019). For women, the rs1004467 was also found to be associated with CAD in a dominant model (P=0.038), the difference remained statistically significant after multivariate adjustment (OR=1.623, 95% CI: 1.023-2.576, P=0.040). The distribution of rs4919687 genotypes showed a significant difference between CAD and control participants in a recessive model (P=0.019), the significant difference was retained after adjustment for covariates (OR=0.417, 95% CI: 0.188-0.926, P=0.032). CONCLUSION: Rs1004467, rs4919687, rs10786712 of CYP17A1 gene are associated with CAD in Han population of China. The TT genotype of rs10786712 could be a protective genetic marker of CAD in men. The CC genotype of rs1004467 and the AA genotype of rs4919687 could be risk genetic markers of CAD in women. However, large sample size study including other SNPs of CYP17A1 should be performed in future studies.

[An improved protocol for primary culture of cardiomyocyte from neonatal rat].

OBJECTIVE: The present study describes an improved in vitro culture method for obtaining high purity, vital and fully functional cardiomyocytes from neonatal rat. METHODS: After cutting ventricular tissue with improved method, ventricular tissues were digested with low concentrations of trypsin overnight at 4 °C, and then underwent collagenase II digestion. Thereafter, cardiomyocytes were purified by combined differential adhesion and chemical inhibition methods. RESULTS: Adherent cardiomyocytes were seen at 12 h after culture, spontaneously beating cardiomyocytes were observed at 24 h after culture, crosslinked cardiomyocytes were found at 48 h after culture, adhesion clustered cardiomyocytes were seen at 72 h after culture, dense network formed from inter-connected was evidenced together with radial arranged cell clusters and cell pseudopodia 96 h the mutual contact woven into and formed radically ordering cell clusters and island-like beating cardiomyocytes at 96 h after culture. The cell survival rate and purity were more than 98%. CONCLUSION: Fully functional spontaneous beating cardiomyocytes can be obtained by the use of this improved primary neonatal rat cardiomyocytes culture method.

The diagnostic and prognostic value of SAA1 as a novel biomarker for acute aortic dissection.

BACKGROUND AND AIMS: Acute aortic dissection (AAD) is a serious life-threatening cardiovascular condition. It is necessary to find rapid and accurate biomarkers for the diagnosis of AAD. This study aimed to determine the efficacy of serum amyloid A1 (SAA1) in the diagnosis and prediction of long-term adverse events in AAD. MATERIALS AND METHODS: Four-dimensional label-free quantification (4D-LFQ) technique was used to identify the differentially expressed proteins (DEPs) in aortic tissues of AAD. After comprehensive analysis, SAA1 was identified as a potential biomarker of AAD. ELISA was used to confirm the expression of SAA1 in serum of AAD patients. Moreover, the source of SAA1 in serum was explored by constructing AAD mouse model. RESULTS: A total of 247 DEPs were identified, of which 139 were upregulated while 108 were downregulated. SAA1 was nearly 6.4-fold and 4.5-fold upregulated in AAD tissue and serum. ROC curve and Kaplan-Meier survival curve confirmed the good efficacy of SAA1 for the diagnosis and prediction of long-term adverse events in AAD. In vivo experiments revealed that SAA1 was mainly derived from the liver when AAD occurred. CONCLUSION: SAA1 can be used as a potential biomarker for AAD with effective diagnostic and prognostic value. SIGNIFICANCE: Despite the advances in medical technology in recent years, the mortality rate of acute aortic dissection (AAD) is still high. It is still challenging for clinicians to diagnose AAD patients on time and reduce the mortality rate. In this study, 4D-LFQ technology was used to identify serum amyloid A1 (SAA1) as a potential biomarker of AAD and was verified in subsequent work. The results of this study determined the efficacy of SAA1 in the diagnosis and prediction of long-term adverse events in patients with AAD.

Genetic polymorphism of the Dab2 gene and its association with Type 2 Diabetes Mellitus in the Chinese Uyghur population.

Objective: The human Disabled-2 (Dab2) protein is an endocytic adaptor protein, which plays an essential role in endocytosis of transmembrane cargo, including low-density lipoprotein cholesterol (LDL-C). As a candidate gene for dyslipidemia, Dab2 is also involved in the development of type 2 diabetes mellitus(T2DM). The aim of this study was to investigate the effects of genetic variants of the Dab2 gene on the related risk of T2DM in the Uygur and Han populations of Xinjiang, China. Methods: A total of 2,157 age- and sex-matched individuals (528 T2DM patients and 1,629 controls) were included in this case-control study. Four high frequency SNPs (rs1050903, rs2255280, rs2855512 and rs11959928) of the Dab2 gene were genotyped using an improved multiplex ligation detection reaction (iMLDR) genotyping assay, and the forecast value of the SNP for T2DM was assessed by statistical analysis of clinical data profiles and gene frequencies. Results: We found that in the Uygur population studied, for both rs2255280 and rs2855512, there were significant differences in the distribution of genotypes (AA/CA/CC), and the recessive model (CC vs. CA + AA) between T2DM patients and the controls (P < 0.05). After adjusting for confounders, the recessive model (CC vs. CA + AA) of both rs2255280 and rs2855512 remained significantly associated with T2DM in this population (rs2255280: OR = 5.303, 95% CI [1.236 to -22.755], P = 0.025; rs2855512: OR = 4.892, 95% CI [1.136 to -21.013], P = 0.033). The genotypes (AA/CA/CC) and recessive models (CC vs. CA + AA) of rs2855512 and rs2255280 were also associated with the plasma glucose and HbA1c levels (all P < 0.05) in this population. There were no significant differences in genotypes, all genetic models, or allele frequencies between the T2DM and control group in the Han population group (all P > 0.05). Conclusions: The present study suggests that the variation of the Dab2 gene loci rs2255280 and rs2855512 is related to the incidence of T2DM in the Uygur population, but not in the Han population. In this study, these variations in Dab2 were an independent predictor for T2DM in the Uygur population of Xinjiang, China.

Genetic variation of RNF145 gene and blood lipid levels in Xinjiang population, China.

Dyslipidemia is one of the main risk factors for coronary heart disease (CHD). The E3 ubiquitin ligase which is encoded by the ring finger protein 145 (RNF145) gene is very important in the mediation of cholesterol synthesis and effectively treats hypercholesterolemia. Thus, the purpose of the present research is to investigate the connection between the polymorphism of the RNF145 gene and cholesterol levels in the populations in Xinjiang, China. A total of 1396 participants (Male: 628, Female: 768) were included in this study for genetic analysis of RNF145 gene, and we used the modified multiple connection detection response (iMLDR) technology to label two SNPs (rs17056583, rs12188266) of RNF145 genotyping. The relationship between the genotypes and the lipid profiles was analyzed with general linear model analysis after adjusting confounding variables. Through the analysis of the two SNPs in RNF145 gene, we discovered that both rs17056583 and rs12188266 were related to total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) concentrations (All P < 0.001). In addition, the association of rs17056583 and rs12188266 with lipid profiles concentrations is still statistically significant after multivariate adjustment of sex, age, smoking, obesity, drinking, diabetes, hypertension and lipid profiles. Meanwhile, we also found that rs17056583 was associated with high triglycerides concentrations before and after adjustment (All P < 0.001). Our study shows that both rs17056583 and rs12188266 SNPs of RNP145 gene are related to TC and LDL-C concentrations in Xinjiang population.

Polymorphisms of rs2483205 and rs562556 in the PCSK9 gene are associated with coronary artery disease and cardiovascular risk factors.

PCSK9 plays a crucial role in lipid metabolism. This case-control study explored the associations of novel single nucleotide polymorphisms (SNPs) of the PCSK9 gene with coronary artery disease (CAD) (≥ 1 coronary artery stenosis ≥ 50%) and its risk factors in the Han population in Xinjiang, China. Four tag SNPs (rs11583680, rs2483205, rs2495477 and rs562556) of the PCSK9 gene were genotyped in 950 CAD patients and 1082 healthy controls. The distributions of genotypes in rs2483205 and rs562556 were significantly different between the groups (all p < 0.05). The TT genotype of rs2483205, GG genotype of rs562556, and their H4 (T-G) haplotype were associated with CAD [odds ratio (OR) 0.65, confidence interval (CI) 0.45-0.95, p = 0.024; 0.63, 0.45-0.90, p = 0.011; 0.50, 0.35-0.70, p < 0.001, respectively]. Additionally, the model (TT + CT vs. CC) of rs2483205 was associated with increased risk of obesity, and the G allele of rs562556 was associated with lower low-density lipoprotein cholesterol (LDL-C), blood glucose, body mass index (BMI), and mean platelet volume (MPV) (all p < 0.05). rs2483205, rs562556, and their H4 haplotype of the PCSK9 gene were associated with CAD. Additionally, rs2483205 is associated with obesity, and rs562556 is associated with LDL-C, blood glucose, BMI, and MPV.

APLP2 gene polymorphisms are associated with high TC and LDL-C levels in Chinese population in Xinjiang, China.

Hyperlipidemia is one of the main risk factors for coronary artery disease (CAD). In the present study, we aimed to explore whether the single-nucleotide polymorphisms (SNPs) in amyloid precursor-like protein (APLP) 2 (APLP2) gene were associated with high lipid levels in Chinese population in Xinjiang, China. We recruited 1738 subjects (1187 men, 551 women) from the First Affiliated Hospital of Xinjiang Medical University, and genotyped three SNPs (rs2054247, rs3740881 and rs747180) of APLP2 gene in all subjects by using the improved multiplex ligation detection reaction (iMLDR) method. Our study revealed that the rs2054247 SNP was associated with serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) levels, and high-density lipoprotein cholesterol (HDL-C) in additive model (all P<0.05). The rs747180 SNP was associated with serum TC and LDL-C levels in additive model (all P<0.05). Our study revealed that both rs2054247 and rs747180 SNPs of the APLP2 gene were associated with high TC and LDL-C levels in Chinese subjects in Xinjiang.

[Experimental study of cardiac function by high-resolution ultrasound in sepsis rats with cecal ligation and puncture].

OBJECTIVE: To evaluate the cardiac function of cecal ligation and puncture (CLP) induced sepsis rats with high-resolution ultrasound. METHODS: According to the method of random number table, 48 adult male Sprague-Dawley (SD) rats were randomly divided into normal control group and sepsis 6, 12, 24, 30, 48 hours groups, with 8 rats in each group. The sepsis model was produced by CLP, and the rats in the normal control group were only anesthetized and resuscitated. The general situation after modeling in each group was observed, and the left ventricular function was assessed by high-resolution echocardiography at all the time points. The abdominal aorta blood of rats was collected, and the serum levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and MB isoenzyme of creatine kinase (CK-MB) were determined by enzyme-linked immunosorbent assay (ELISA). The myocardial tissue was harvested, and the pathological changes in myocardial tissue were observed by hematoxylin-eosin (HE) staining. RESULTS: The rats challenged to CLP displayed symptoms of sepsis, such as depression, ruffled fur, decreased diet and activity, and the symptoms became more obvious with the extension of time. High-resolution echocardiography could clearly show the structure of left ventricle in each group and obtain satisfactory M-mode echocardiography of left ventricle. The heart rate (HR) of rats in all sepsis groups was elevated with the increase in model time as measured by high-resolution ultrasound, and it was significantly higher than that in the normal control group at 12, 24, 30 hours (bpm: 359.66±23.33, 361.35±12.85, 392.67±11.33 vs. 306.24±29.79, all P < 0.05). Stroke volume (SV) and cardiac output (CO) in sepsis rats were decreased with the increase in model time, while left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were increased first and then decreased, and SV and LVEF in sepsis 48 hours group were significantly lower than those in the normal control group [SV (µL): 78.43±17.52 vs. 122.61±15.88, LVEF: 0.763±0.018 vs. 0.902±0.011, both P < 0.05]. Left ventricular weight (LVW) in all sepsis groups was increased to different degrees as compared with that in the normal control group, as well as the left ventricular anterior and posterior wall thickness increased in diastole and systole. Compared with the normal control group, the left ventricular posterior wall thickness was increased significantly at the end of diastolic and systolic period in the sepsis 12 hours group, and the left ventricular anterior wall thickness was also increased significantly at the end of diastolic period in the sepsis 48 hours group. The serum levels of TNF-α, IL-1ß and CK-MB in sepsis rats were increased first and then decreased with the extension of model making time. The above parameters in the sepsis 48 hours group were still significantly higher than those in the normal control group [TNF-α (ng/L): 61.59±3.99 vs. 16.87±4.89, IL-1ß (ng/L): 255.03±13.23 vs. 119.59±10.43, CK-MB (µg/L): 1.27±0.15 vs. 0.52±0.15, all P < 0.05]. HE staining showed that the myocardial striations of the rats in the normal control group were clear and complete, with normal morphology and orderly arrangement of cardiac cells. However in the sepsis groups, myocardial cells were swollen, ruptured and necrotic, and inflammatory cells were infiltrated, with myocardial fibers ruptured and necrosis dissolved, and the above pathological manifestations gradually increased with the extension of the model making time. CONCLUSIONS: High-resolution ultrasound can evaluate the cardiac function of CLP induced sepsis rat model more comprehensive, and the consequence of evaluation index is consistent with the expression level of myocardial enzyme and histopathologic manifestations.

TT genotype of rs2941484 in the human HNF4G gene is associated with hyperuricemia in Chinese Han men.

The aim of the study is to investigate the association between the human hepatocyte nuclear factor 4 gamma (HNF4G) gene and hyperuricemia in Chinese Han population. A total of 414 hyperuricemia patients and 406 gender and age-matched normouricemic controls were enrolled. Four single nucleotide polymorphisms were genotyped as genetic markers for the human HNF4G gene (rs2977939, rs1805098, rs2941484, rs4735692). Data were analyzed for two separate groups: men and women. For rs2941484, the genotype distribution frequency in hyperuricemic subjects and was significantly different from that in normouricemic controls in men (P = 0.038). Meanwhile, in recessive model of rs2941484, the distribution frequency of TT genotype and CC+CT genotypes also differed significantly between the hyperuricemia men and normouricemic men (P = 0.011). For the other 3 SNPs in both men and women, there was no difference in the genotype and allele and distribution frequency between the hyperuricemia patients and normouricemic controls. In men, after adjustments for BMI, SBP, DBP, fasting glucose, total cholesterol, triglycerides, low density lipoprotein cholesterol and creatinine, the men with the TT genotype of rs2941484 were found to have significantly higher probability of suffering from hyperuricemia than the ones with CT and CC genotypes (OR = 2.170, P < 0.001). Therefore, TT genotype of rs2941484 in the human HNF4G gene might be a gender-specific genetic marker for hyperuricemia in Chinese Han men.

CYP19A1 polymorphisms associated with coronary artery disease and circulating sex hormone levels in a Chinese population.

BACKGROUND: The relationship between CYP19A1 genetic polymorphisms and coronary artery disease (CAD) remains unclear. Thus, the aim of the present study was to investigate the association of CYP19A1 genetic polymorphisms with CAD in Han and Uygur populations and to characterize the association between the levels of sex hormones and aromatase with single-nucleotide polymorphisms (SNPs) in CYP19A1 genes in Chinese women. RESULTS: There were significant differences in the genotype distributions of rs2236722 and rs4646 between CAD patients and control subjects in the Uygur population. The rs4646 was found to be associated with CAD in the dominant model (CC vs. CA + AA) and the additive model (CA vs. CC + AA) (both P ≤ 0.001). The difference remained statistically significant after multivariate adjustment (OR = 0.483, 95% CI: 0.338-0.690, P = 0.000; and OR = 1.844, 95% CI: 1.300-2.617, P = 0.001, respectively). In normal Uygur postmenopausal women, there were significant differences in the genotype distributions of rs4646 and the circulating hormone and aromatase levels between CAD patients and control subjects. The differences in estradiol and aromatase levels remained statistically significant after multivariate adjustment (OR = 0.889, 95% CI: 0.817-0.969, P = 0.007; and OR = 0.947, 95% CI: 0.936-0.957, P = 0.000, respectively). Additionally, there were differences in sex hormone levels between the different ethnicities among the Xinjiang Chinese population. MATERIALS AND METHODS: Among a total of 1,064 Han individuals (614 men and 450 women) and 790 Uygur individuals (484 men and 306 women), 498 postmenopausal women (265 Han and 233 Uygur individuals) were selected. Four SNPs (rs2236722, rs2304463, rs4646, and rs4275794) were genotyped using the improved multiplex ligation detection reaction (iMLDR) technique. The estradiol and testosterone levels were determined using a radioimmunoassay based on GC-2016γ. In addition, an enzyme-linked immunosorbent assay (ELISA) was performed to determine the serum P450 aromatase levels. CONCLUSIONS: The results of this study indicate that the rs2236722 and rs4646 of the CYP19A1 gene are associated with CAD and circulating sex hormone levels in the Xinjiang population of China.

[Isolation, culture and identification of human umbilical vein endothelial cells].

OBJECTIVE: To establish a simple, reliable and efficient isolation and culture method of human umbilical vein endothelial cells (HUVECs) in vitro. METHODS: Type 2 collagenase was used to digest umbilical cord and separate HUVECs. The cells were cultured in the endothelial cell culture medium (ECM). The cell morphology was observed under an inverted phase-contrast microscope. Immunofluorescence technique was applied to detect the expression of von Willebrand factor (vWF). Cell purity was determined by detecting CD31 level on cell surface with flow cytometry. Tube formation assay was used to test the function of the endothelial cells after cryopreservation in vitro. RESULTS: HUVECs successfully isolated were proved with high purity and good activity. HUVECs of primary generation could merge into a single layer one week after isolation. The cells showed a typical cobblestone-like arrangement. Immunofluorescence technique validated that the cells could widely express vWF and the expression frequency of CD31 was 93.1%. The cells were still capable of forming the lumen structure after cryopreservation, indicating that the standardized cryopreservation method could well maintain the cell function. CONCLUSION: This is a simple, reliable and efficient method of isolating and culturing HUVECs in vitro.

4-Phenylbutyric Acid Induces Protection against Pulmonary Arterial Hypertension in Rats.

BACKGROUND: Endoplasmic reticulum (ER) stress has been implicated in the pathophysiology of various pulmonary diseases via the activation of the unfolded protein response. However, the role of ER stress in pulmonary arterial hypertension (PAH) remains unclear. The well-known chemical chaperone 4-phenylbutyric acid (4-PBA) inhibits ER stress signaling. We hypothesized that known chemical chaperones, including 4-PBA, would inhibit the activation of ER stress and prevent and/or reverse PAH. METHODS AND RESULTS: Male Wistar rats were randomly divided into four groups: a normal control group (NORMAL group), a PAH group, and two PAH model plus 4-PBA treatment groups. The latter two groups included rats receiving 4-PBA by gavage each day as a preventive measure (the PRE group, with PBA starting on the day of PAH induction and continuing for 4 weeks) or as a reversal measure (the REV group, with PBA starting on the third week of PAH induction and continuing for 2 weeks). The PAH model was induced by intraperitoneally administering monocrotaline. The mean pulmonary artery pressure and mean right ventricular pressure were lower in the REV and PRE groups than in the NORMAL group. Furthermore, 4-PBA improved pulmonary arterial remodeling and suppressed the expression of ER stress indicators. CONCLUSION: Our findings indicate that PAH induces ER stress and provokes pulmonary arterial and right ventricular remodeling. Additionally, we show that attenuation of ER stress has the potential to be an effective therapeutic strategy for protecting pulmonary arteries.