Abstract:Coronary atherosclerotic heart disease (CHD) is a common clinical chronic heart disease. Inflammation and immune response play pivotal roles in the development of atherosclerosis and ischemic myocardial diseases, and have become the focuses of cardiovascular disease research. Abnormal inflammatory immune response promotes atherogenesis and affects myocardial injury and tissue repair after acute myocardial infarction. Histidine decarboxylase (HDC) is the unique enzyme responsible for histamine generation. Histamine is a biogenic amine that has multiple functions through the activation of its widely distributed histamine receptors. Histamine regulates the differentiation and function of innate immune cells and adaptive immune cells. Recent studies have identified the new cellular source of histamine in immune cells and in ischemic myocardial injury. Targeting histamine and its downstream signaling molecules may provide new research strategies for the prevention and treatment of coronary heart disease.

Abstract:Aim By establishing methamphetamine (METH) poisoning model and myocardial cell poisoning model in SD rats, to detect the expressions of gap junction protein connexin 43 (Cx43) and its phosphorylation (p-Cx43) at S368 site. By examining the expressions of Cx43 and its S368 site p-Cx43 in human myocardial tissues after taking METH, to analyze the relationship between the expressions of Cx43, p-Cx43 and METH-induced myocardial toxicity, and to investigate the role of Cx43 and its S368 site p-Cx43 in myocardial toxicity induced by METH. Methods METH chronic poisoning animal model in SD rats and primary METH poisoning cell model of cardiac muscle in neonatal SD rats were established. The proteins were extracted and the expressions of Cx43 and p-Cx43 proteins were detected by Western blot. The relationship between the levels of Cx43 and its S368 site p-Cx43 and METH-induced myocardial toxicity was analyzed. The myocardial tissues of METH users confirmed by toxicity test in Forensic Judicial Appraisal Center of Guizhou Medical University were collected as experimental group and those without any drugs as control group. After routine paraffin section, HE staining was used to observe the structural changes of myocardium in two groups. Immunohistochemical staining and Western blot were used to detect the expressions of Cx43 and its S368 site p-Cx43. Results (1)Expressions of Cx43 and its S368 site p-Cx43 in METH chronic poisoning animal model was significantly lower than those in control group (P＜0.05). (2)Expressions of Cx43 and its S368 site p-Cx43 in METH poisoning cell concentration and time gradient model were significantly lower than those in control group (P＜0.05). (3)Compared with the control group, the atrophy, necrosis and focal hemorrhage of human cardiac myocytes were observed in the experimental group. (4)Compared with the control group, the expression levels of Cx43 and S368 site p-Cx43 in human myocardium in the experimental group were lower than those in the control group, mainly expressed as the decrease of brown-yellow staining at intercalated disc between cardiac myocytes, and some of them showed lateral membrane changes. (5)Expressions of Cx43 and S368 site p-Cx43 proteins of human myocardium in experimental group were lower than those in control group (P＜0.05). Conclusion METH can reduce the expressions of Cx43 and its S368 site p-Cx43 in myocardium, thus destroying the structure of myocardium and affecting the normal function of heart.

Abstract:Aim To investigate the role of interlekutin-10 (IL-10) in cardiomyocyte metabolism. MethodsCardiomyocyte lipotoxicity and glucose utilization reduction was induced by palmitate. Cardiomyocytes were treated with IL-10 and 2-NBDG uptake assay was adopted to assess the glucose utilization in cells. Lactic acid and oxidative phosphorylation were used to assess glycolysis and oxidation of glucose, respectively. Immuno-fluorescence was used to evaluate mitophagy in cardiomyocytes. RT-qPCR and Western blot were used to detect PINK1 expression. Results Compared with the control, IL-10 treatment approximately doubled the amount of 2-NBDG in cardiomyocytes. The supernatant and intracellular lactic acid were both reduced. Moreover, LC3-GFP was enhanced in mitochondrial aggregation and the PINK1 expression was up-regulated, which indicated mitophagy increase in cardiomyocytes. Conclusion IL-10 may re-balance cardiomyocytes metabolism substrates by increasing glucose utilization, glycolysis and oxidative phosphorylation through inducing mitophagy mediated by PINK1 up-expression.

Abstract:Aim To investigate the effect of curcumin on the progression of atherosclerosis and macrophage polarization in vivo. Methods The apolipoprotein E deficient (ApoE－/－) mice were fed with high fat diet to establish atherosclerosis model. The aortas were isolated for haematoxylin and eosin, masson trichrome, picrosirus red, oil red O and immunofluorescence staining. Inducible nitric oxide synthase (iNOS) and CD206 were utilized as biomarkers of M1 and M2 phenotypes, respectively. Quantitative real-time polymerase chain reaction (PCR) was carried out to examine the gene expression of inflammatory factors. Results Curcumin significantly decreased atherosclerotic burden and plaque vulnerability in the experimental atherosclerosis model. Furthermore, curcumin decreased the ratio of M1/M2 macrophages together with the gene expressions of pro-inflammatory interleukin 1beta (IL-1β), inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), but promoted the levels of anti-inflammatory cytokines IL-10, Ym1, Fizz1 in the atherosclerotic plaque. Conclusion Curcumin could alleviate the progression of atherosclerosis by inhibiting macrophage polarizing towards M1 phenotype as well as inflammatory response.

Abstract:Aim To investigate the effect of microRNA-30b(miR-30b)on the migration of rat vascular smooth muscle cells (VSMC). Methods Rat VSMC were isolated and cultured in vitro. VSMC were randomly divided into normal control group (no transfection), miR-NC group (transfected miR-NC concentration 50 nmol/L), miR-30b mimics group (transfected miR-30b mimics, concentration 50 nmol/L). Real-time quantitative PCR was used to detect the expression of miR-30b and E-cadherin. The mobility of VSMC was detected by scratch healing test. The migration ability of VSMC was detected by Transwell assay. The expression of E-cadherin protein was detected by Western blot. Results Compared with the normal control group and the miR-NC group, the expression level of miR-30b was increased in the miR-30b mimics group (P<0.05). The results of the scratch-healing experiment showed that the migration ability of the miR-30b mimics group was significantly weaker than that of the normal control group and the miR-NC group (P<0.05). Transwell experiments showed that the migration ability of miR-30b mimics group was weakened (P<0.05). The expression of E-cadherin mRNA and protein in miR-30b mimics group was significantly higher than that in normal control group and miR-NC group (P<0.05). Conclusion miR-30b can up-regulate the expression of E-cadherin, thereby inhibiting the migration of rat VSMC.

Abstract:Aim To investigate whether proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates monocyte-endothelial cell adhesion through Toll-like receptor 4 (TLR4)/nuclear factor κB (NF-κB)/cyclooxygenase-2 (COX-2) pathway in human umbilical vein endothelial cells (HUVECs). Methods HUVECs were incubated with oxidized low density lipoprotein (ox-LDL), real-time PCR and Western blot assay for detection of PCSK9, TLR4, NF-κB, COX-2 mRNA and protein expression. After treatment with ox-LDL, recombinant PCSK9 protein was incubated or PCSK9 siRNA was transfected into HUVECs. Then the expression of TLR4, NF-κB p65, COX-2 mRNA and protein was detected. After treatment with ox-LDL, human recombinant PCSK9 protein was incubated with TLR4 inhibitor TAK-242 or NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) to detect mRNA and protein expression of NF-κB p65 and COX-2. After COX-2 inhibitor (NS398) and human recombinant PCSK9 protein were treated successively, THP-1 monocytes were added and monocyte-endothelial cell adhesion was detected. Results ox-LDL up-regulates the mRNA and protein expression of PCSK9, TLR4, NF-κB and COX-2 in HUVECs (all P＜0.05). Human recombinant PCSK9 protein up-regulated TLR4, NF-κB, COX-2 mRNA and protein expression on ox-LDL basis (all P＜0.05). PCSK9 siRNA transfection down-regulated the up-regulation of TLR4, NF-κB, COX-2 mRNA and protein expression by ox-LDL (all P＜0.05). TAK-242 inhibits the up-regulation of TLR4 and NF-κB mRNA and protein expression by human recombinant PCSK9 protein (all P＜0.05). PDTC inhibits the up-regulation of NF-κB and COX-2 mRNA and protein expression by human recombinant PCSK9 protein (all P＜0.05). NS398 inhibits monocyte-endothelial cell adhesion induced by human recombinant PCSK9 protein (all P＜0.05). Conclusion PCSK9 regulates monocyte-endothelial cell adhesion via TLR4/NF- κ B/COX-2 pathway.

Abstract:Aim To investigate the effect of miR-224-5p on the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) and the lipid uptake of HepG2 cells. Methods The position, conservativeness and seed sequence of miR-224-5p gene were analyzed by bioinformatics method. The binding sites and binding free energies of miR-224-5p to PCSK9 were analyzed in databases such as Targetscan, miRanda, miRDB and RNAhybrid. Direct targeted binding of miR-224-5p to PCSK9 mRNA 3′UTR was verified by double luciferase reporter gene. Western blot was used to detect the effects of miR-224-5p mimic and miR-224-5p inhibitor on PCSK9 and low density lipoprotein receptor (LDLR) proteins. LDLR on the cell membrane was directly observed with cellular immunofluorescence. Oil red O staining and DiI-LDL were respectively used to observe the effects of miR-224-5p on lipid droplet content and lipid uptake in HepG2 cells. Results Bioinformatics analysis revealed that the human miR-224-5p gene was located in Xq28 and highly conserved among different species. MiR-224-5p and PCSK9 mRNA 3′UTR had the basis of targeted binding, and the binding free energy was low. The double luciferase reporter gene assay showed that miR-224-5p mimic could inhibit the luciferase activity of PCSK9-WT 3′UTR, but not PCSK9-Mut 3′UTR, suggesting that the PCSK9 mRNA 3′UTR was the target of miR-224-5p. Further experiments showed that the miR-224-5p mimic could significantly inhibit the expression of PCSK9 protein and increase the content of LDLR protein. The expression of PCSK9 increased and the level of LDLR decreased after the down-regulation of miR-224-5p. In addition, oil red O staining showed that lipid droplets in HepG2 cells decreased significantly in the miR-224-5p mimic group, while lipid droplets in HepG2 cells increased significantly in the miR-224-5p inhibitor group. High expression of miR-224-5p significantly promoted LDLC uptake by HepG2 cells. Conclusion miR-224-5p targeting PCSK9 mRNA 3′UTR inhibits the expression of PCSK9, thereby reducing the content of lipid droplets in HepG2 cells and increasing the uptake of lipid by HepG2 cells.

Abstract:Aim To study the regulatory effect and molecular mechanism of glucagon-like peptide-1 (GLP-1) on pyroptosis of umbilical vein endothelial cells (HUVEC) induced by oxidized low density lipoprotein (ox-LDL). Methods HUVEC was cultured and divided into control group, ox-LDL group, GLP-1 group (10 nmol/L, 100 nmol/L, 1 000 nmol/L), GLP-1+miR-22 inhibitor group, miR-22 inhibitor group, miR-22 mimic group, negative control (NC) inhibitor group and NC mimic group. Flow cytometry was used to detect apoptotic rate, fluorescence quantitative PCR was used to detect the expression of microRNA-22(miR-22), Western blot was used to detect the expression of NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing CARD (ASC) and caspase-1, enzyme-linked immunosorbent assay was used to detect the content of interleukin 1beta (IL-1β) and interleukin-18(IL-18). Results Compared with the control group, the apoptotic rate, the expression of NLRP3, ASC, caspase-1 in cells and the levels of IL-1β and IL-18 in the culture medium of ox-LDL group significantly increased, while the expression of miR-22 significantly decreased (P<0.05). Compared with ox-LDL group, the apoptotic rate, the expression of NLRP3, ASC, caspase-1 in cells and the levels of IL-1β and IL-18 in the culture medium of GLP-1 group significantly decreased, while the expression of miR-22 significantly increased (P<0.05). Compared with GLP-1 group, the apoptotic rate, the expression of NLRP3, ASC, caspase-1 in cells and the levels of IL-1β and IL-18 in the culture medium of GLP-1+miR-22 inhibitor group significantly increased, while the expression of miR-22 significantly decreased (P<0.05). The expression of NLRP3, ASC, caspase-1 in cells and the levels of IL-1β and IL-18 in the culture medium of miR-22 inhibitor group were significantly higher than those of NC inhibitor group, while the expression of NLRP3, ASC, caspase-1 in cells and the levels of IL-1β and IL-18 in the culture medium of miR-22 mimic group were significantly higher than those of NC mimic group. Conclusion GLP-1 can alleviate ox-LDL-induced endothelial cell pyroptosis through the miR-22/NLRP3 pathway.

Abstract:Aim To investigate the correlation between serum cystathionine-β-synthase(CBS), hydrogen sulfide (H₂S) levels and carotid intima-media thickness (CIMT) in patients with hypertension. Methods Between October 2017 and March 2018, a total of 116 patients with essential hypertension were enrolled from in-patient department of our hospital. The blood pressure, homocysteine (Hcy), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDLC) and low density lipoprotein cholesterol (LDLC) were measured in all selected hypertensive patients.At the same time, the levels of CIMT, CBS and H₂S were detected. According to the levels of Hcy, the patients with hypertension were divided into two groups:H hypertension group (Hcy≥10 μmol/L) and non H hypertension group (Hcy<10 μmol/L), and the differences of Hcy, blood lipids, CBS, H₂S and CIMT were compared. The correlation between the indexes and CIMT was analyzed by Pearson test. Results The CIMT of H hypertension group was higher than that of non H hypertension group (P<0.05), and the levels of H₂S and CBS in H hypertension group were lower than that in non H hypertension group (P<0.05). Correlation analysis showed that Hcy was positively correlated with CIMT in hypertensive patients (r=0.752, P<0.05). CBS and H₂S were negatively correlated with Hcy (r =－0.413, －0.698, P<0.05) and with CIMT (r=－0.518, －0.779, P<0.05). Conclusions Compared with non H hypertensive patients, the degree of carotid atherosclerosis is more pronounced in patients with H hypertension. In patients with hypertension, the levels of CBS and H₂S are closely related with carotid atherosclerosis, which is expected to be an early predictor of atherosclerosis in hypertensive patients.

Abstract:Aim Detection of relative expression levels of plasma miR-21 by a case-control study of acute aortic dissection (AAD), combined with receiver operating curve (ROC) and related clinical data to evaluate the diagnostic value of miR-21 for AAD. Methods 30 samples of AAD patients, 30 samples of angina patients, 29 patients with acute myocardial infarction (AMI) and 29 patients in the control group, clinical data of each group were also collected. The plasma levels of miR-21 and housekeeping gene miR-16 in each group were identified by quantitative reverse transcriptase polymerase amplification reaction, and the relative expression of miR-21 was calculated. Results Compared with the control group, the relative expression level of miR-21 in plasma of AAD group were significantly increased (P<0.05). There was no significant difference in plasma miR-21 expression between angina pectoralis group vs AAD group and AMI group vs AAD group (P>0.05). ROC curve analysis showed that the area under the curve (AUC) was 0.664.The 95% confidence interval was 0.520~0.809, and the sensitivity of plasma miR-21 to AAD diagnosis was 40%, and the specificity was 96.6%. When the comparative expression of miR-21 was 0.034, the sensitivity of plasma miR-21 to AAD diagnosis was 80%, and the specificity was 20.7%. Conclusion The detection of plasma miR-21 has definite clinical value for the diagnosis of AAD, but it is not enough to support miR-21 as an ideal molecular diagnostic marker for AAD.

Abstract:Aim To study the effects of first using amiodarone and then using ibutilide on efficacy and transmural dispersion of repolarization in cardioversion of new(7 d～90 d) persistent atrial fibrillation(PAF).Methods 76 patients of new PAF were randomly divided into two groups:ibutilide group (38 cases) and sequential group (38 cases). Patients(38 cases) in the ibutilide group were treated with ibutilide intravenous injection, initial dose 1 mg(or 0.01 mg/kg), slow injection after dilution; amiodarone group(50 cases) were treated with amiodarone intravenous injection on conversion, initial dose 150 mg, diluted uniform injection for 10 min. If it failed, the same dose and method were used for the second time at intervals of 10 min; Patients(38 cases) in the sequential group were first diluted with amiodarone at 150 mg and then injected with it at a constant rate for 10 min. If it failed, 1 mg (or 0.01 mg/kg) of ibutilide was used to dilute the solution and then inject at a constant rate for 10 min. The success rate of atrial fibrillation recovery within 24 h after second administration, the incidence of ventricular arrhythmia were compared between two groups, changes in the ratios of QT interval and Tpeak-end/QT interval ratio (30 min, 1 h, 3 h, 4 h) were detected. Results After the first injection, the success rate of atrial fibrillation was higher than that of amiodarone(P＜0.05); Total reinjection, comparison of the success rate of PAF reversion between the two groups (P＞0.05), showed no significant difference. In patients with successful outcome, the dosages of ibutilide individuals in the sequential group were significantly lower than that in the ibutilide group(P＜0.01); Tpeak-end/QT in the ibutilide group was higher than that in the sequential group immediately after medication and 30 min after medication(P＜0.01); The tpeak-end /QT of the ibutilide group was significantly increased immediately after the end of the treatment(P＜0.05), after 1 h of administration, the drug returned to the level before administration(P＞0.05); Comparison of each time point after administration and before administration showed that there was no statistically significant difference of the Tpeak-end/QT in the sequential group(P＞0.05). Conclusion The atrial fibrillation conversion rate of ibutilide was higher than that of amiodarone, however, the transmural dispersion of repolarization(Tpeak-end/QT) increased after ibutilide alone; for first using amiodarone and then using ibutilide, compared to the single usage of ibutilide for twice, the success rate of atrial fibrillation is comparable, the transmural dispersion of repolarization(Tpeak-end/QT)do not increase, there is a tendency to reduce the incidence of ventricular arrhythmia.

Abstract:The process of atherosclerotic lesions is a proliferative response induced by arterial intimal injury, which occurs in the bifurcation and branching regions of the arteries with low shear stress (LSS). LSS regulates gene expression and phenotype transformation by activating membrane receptors and intracellular signal transduction on cells, and plays an important role in the occurrence and development of atherosclerosis. This article reviews the relationship between LSS and endothelial cell inflammation, endothelial-to-mesenchymal transition, endothelial cell autophagy and its regulatory mechanism, hoping to provide new ideas and strategies for the prevention and treatment of atherosclerosis.

Abstract:Cardiovascular and cerebrovascular diseases caused by atherosclerosis are the leading cause of morbidity and mortality worldwide, which has a great harm to human health. Macrophages under the vascular intima would uptake more cholesterol and efflux less in the state of dyslipidemia, oxidation and inflammation, leading to the accumulation of a large number of lipid droplets (LDs) and formation of foam cells, as a key step in the development of atherosclerotic plaques. Autophagy serves as a conserved degradation process to contribute to cellular metabolism homeostasis. With autophagy deficiency or abnormality, the ability of cell self-clearing decreases, leading to metabolic stress, oxidation, inflammation and cell death, which has a close relationship with atherosclerosis. This review focuses on the role of macrophage autophagy in cholesterol metabolism, inflammation, oxidative stress and apoptosis.

Abstract:The most ideal treatment for acute cerebral infarction is the recanalization of occlusive vessels as soon as possible. Intravenous thrombolytic therapy is an effective treatment for acute cerebral infarction. Bridging therapy improves the recanalization rate of occlusive vessels, but there are still some patients with residual vascular stenosis. Platelets are known to play an important role in the occurence and development of acute cerebral infarction. One of the key factors for reocclusion of blood vessels after thrombolytic / bridging treatment is the prohibition of antiplatelet aggregation within 24 hours after thrombolytic therapy. Platelet aggregation and activation make a part of the patients with residual artery stenosis reoccluded. Inorder to explore the feasibility and safety of using antiplatelet drugs within 24 hours after intravenous thrombolysis/bridging treatment and improving the prognosis of patients, this paper reviewed the mechanism of platelet activation and the platelet activation status after intravenous thrombolysis/bridging therapy in acute cerebral infarction and the related research of antiplatelet combined with intravenous thrombolysis/bridging therapy.

Abstract:The formation of atherosclerotic plaque is the main mechanism of coronary heart disease. The instability of plaque is significantly related to the occurrence of acute coronary syndrome. At present, the detection of plaque instability is mainly through intravascular ultrasound, optical coherence tomography and other invasive operations. The microRNA, apelin, galectin-3, endocan and other serological indicators are directly related to the stability of plaques, which can be used as biological indicators to predict the stability of plaques. This article reviews the research progress on the relationship between microRNA, apelin, galectin-3, endocan and atherosclerotic plaque stability.

Abstract:The development of cardiovascular disease is related to chronic inflammation. p38 mitogen activated protein kinase (p38MAPK) mediated signaling pathway plays an important role in cardiovascular cell inflammation, proliferation, differentiation, migration and metabolism. Inhibition of p38MAPK can effectively inhibit the expression of inflammatory mediators. In terms of safety, p38 inhibitors are unacceptable and it is necessary to study the downstream substrate. Mitogen-actitated protein kinase actitaved protein kinase 2 (MK2) is an important downstream substrate of p38MAPK and is involved in the development of cardiovascular diseases. Therefore, inhibition of MK2 activity is of great clinical significance in the treatment and prevention of cardiovascular diseases. This article mainly reviews the structure and function of MK2 and its role in cardiovascular diseases.