[Dual-specificity Phosphatase 1 Suppresses Vascular Smooth Muscle Cell Calcification by Optical Atrophy 1-related Pathway].

Objective To investigate the effect of dual-specificity phosphatase 1/optical atrophy 1 (DUSP1/OPA1) signaling pathway on vascular smooth muscle cell (VSMC) calcification.Methods An in vitro model of VSMC calcification was induced by exposure to ß-glycerophosphate and calcium chloride.VSMC calcification was assessed by Alizarin Red S staining and calcium content by ELISA.Apoptosis was detected by TUNEL.Western blotting was employed to determine the protein levels of DUSP1,OPA1,Runt-related transcription factor 2 (Runx-2),bone morphogenetic protein 2 (BMP-2),and cysteinyl aspartate-specific proteinase-3 (Caspase-3).The effects of DUSP1 overexpression and OPA1 knockdown on cell calcification were investigated.Results Calcium chloride and ß-glycerolphosphate induced VSMC calcification and down-regulated the expression levels of DUSP1 (t=11.951,P<0.001) and OPA1 (t=8.487,P<0.001).DUSP1 overexpression promoted OPA1 expression (t=-8.921,P<0.001),attenuated VSMC calcification,reduced calcium content and apoptosis rate,and down-regulated the expression of Runx-2,BMP-2,and active Caspase-3 (all P<0.001).OPA1 knockdown increased calcium content and apoptosis rate,up-regulated the expression of Runx-2,BMP-2,and active Caspase-3,and promoted VSMC calcification (all P<0.001).Conclusion DUSP1 may inhibit the VSMC calcification through the OPA1 signaling pathway.

The association between plasma furin and cardiovascular events after acute myocardial infarction.

BACKGROUND: Furin is the key enzyme involved in the cleavage of pro-BNP and plays a critical role in the cardiovascular system through its involvement in lipid metabolism, blood pressure regulation and the formation of atheromatous plaques. NT-proBNP and recently, corin, also a key enzyme in the cleavage of pro-BNP, have been accepted as predictors of prognosis after acute myocardial infarction (AMI). This cohort study was conducted to investigate the relationship between plasma furin and the prognostic outcomes of AMI patients. METHODS: In total, 1100 AMI patients were enrolled in the study and their plasma furin concentrations were measured. The primary endpoint was major adverse cardiac events (MACE), a composite of cardiovascular (CV) death, non-fatal myocardial infarction (MI) and non-fatal stroke. The associations between plasma furin concentration and AMI outcomes were explored using Kaplan-Meier curves and multivariate Cox regression analysis. RESULTS: The results showed a slight increase in mean cTNT in patients with higher furin concentrations (P = 0.016). Over a median follow-up of 31 months, multivariate Cox regression analysis indicated that plasma furin was not significantly associated with MACE (HR 1.01; 95% CI 0.93-1.06; P = 0.807) after adjustment for potential conventional risk factors. However, plasma furin was associated with non-fatal MI (HR 1.09; 95% CI 1.01-1.17; P = 0.022) in the fully adjusted model. Subgroup analyses indicated no relationship between plasma furin and MACE in different subgroups. CONCLUSIONS: This study found no association between plasma furin and risk of MACE. Thus, plasma furin may not be a useful predictor of poor prognosis after AMI. However, higher levels of plasma furin may be associated with a higher risk of recurrent non-fatal MI.

Poor cardiovascular health status among Chinese women.

BACKGROUND: Systematic investigation and analysis of cardiovascular health status (CVHS) of Chinese women is rare. This study aimed to assess CVHS and atherosclerotic cardiovascular disease (ASCVD) burden in the Chinese women physicians (CWP) and community-based non-physician cohort (NPC). METHODS: In this prospective, multicenter, observational study, CVHS using the American Heart Association (AHA) defined 7 metrics (such as smoking and fasting glucose) and ASCVD risk factors including hypertension, hyperlipidemia and type-2 diabetes were evaluated in CWP compared with NPC. RESULTS: Of 5832 CWP with a mean age of 44 ± 7 years, only 1.2% achieved the ideal CVHS and 90.1% showed at least 1 of the 7 AHA CVHS metrics at a poor level. Total CVHS score was significantly decreased and ASCVD risk burden was increased in postmenopausal subjects in CWP although ideal CVHS was not significantly influenced by menopause. Compared to 2596 NPC, fewer CWP had ≥ 2 risk factors (8% vs. 27%, P < 0.001); CWP scored significantly higher on healthy factors, a composite of total cholesterol, blood pressure, fasting glucose (P < 0.001), but, poorly on healthy behaviors (P < 0.001), specifically in the physical activity component; CWP also showed significantly higher levels of awareness and rates of treatment for hypertension and hyperlipidemia, but, not for type-2 diabetes. CONCLUSION: Chinese women's cardiovascular health is far from ideal and risk intervention is sub-optimal. Women physicians had lower ASCVD burden, scored higher in healthy factors, but, took part in less physical activity than the non-physician cohort. These results call for population-specific early and improved risk intervention.

Increased expression of ryanodine receptor type-2 during atrial fibrillation by miR-106-25 cluster independent mechanism.

Atrial fibrillation (AF), the most frequently encountered cardiac arrhythmia in the clinical setting and the foremost cause of stroke, results from a progressive decrease in atrial refractoriness. In addition, defective calcium signaling has been shown to play a central role in AF pathogenesis. Recently it was shown that the miR-106b-25 cluster is suppressed in patients with AF, which increased ryanodine receptor 2 (RyR2) expression. Expression of the miR-106b-25 cluster and RyR2 protein were determined in our institutional series of patients with AF. Hemodynamic properties, RyR2 binding, suppression of ATP2A2 (encoding ATPase sarcoplasmic/endoplasmic reticulum Ca2 + transporting 2) were also determined. We found that all patients had elevated RyR2 protein expression; however, a cohort of patients with AF had high miR-93, miR-106b, and miR-25 expression. There was no difference in hemodynamic properties, RyR2 binding, or suppression of ATP2A2 in either cohort of patients with AF when compared to patients with normal sinus rhythm (NSR). Immunoblot assay showed hyperactive Akt, S6K, and S6 kinases in patients with AF as compared to patients with NSR. Protein kinase C activation, as measured by PKC phosphorylation, was also hyperactive in patients with AF. Cumulatively, our findings show that RyR2 expression is regulated by multiple mechanisms including the miR-106b-25, and that PKC activation might provide novel clues to increased intracellular calcium levels during AF pathogenesis.

Early Warning of Acute Altitude Sickness by Physiological Variables and Noninvasive Cardiovascular Indicators.

Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude. Methods One hundred and six Han nationality male individuals were recruited to this research. Dynamic electrocardiogram, treadmill exercise test, echocardiography, routine blood examination and biochemical analysis were performed when subjects at sea level and entering the plateau respectively. Then multiple regression analysis was performed to construct a multiple linear regression equation using the Lake Louise Score as dependent variable to predict the risk factors at sea level related to acute mountain sickness (AMS). Results Approximately 49.05% of the individuals developed AMS. The tricuspid annular plane systolic excursion (22.0±2.66 vs. 23.2±3.19 mm, t=1.998, P=0.048) was significantly lower in the AMS group at sea level, while count of eosinophil [(0.264±0.393)×109/L vs. (0.126±0.084)×109/L, t=-2.040, P=0.045], percentage of differences exceeding 50 ms between adjacent normal number of intervals (PNN50, 9.66%±5.40% vs. 6.98%±5.66%, t=-2.229, P=0.028) and heart rate variability triangle index (57.1±16.1 vs. 50.6±12.7, t=-2.271, P=0.025) were significantly higher. After acute exposure to high altitude, C-reactive protein (0.098±0.103 vs. 0.062±0.045 g/L, t=-2.132, P=0.037), aspartate aminotransferase (19.7±6.72 vs. 17.3±3.95 U/L, t=-2.231, P=0.028) and creatinine (85.1±12.9 vs. 77.7±11.2 mmol/L, t=-3.162, P=0.002) were significantly higher in the AMS group, while alkaline phosphatase (71.7±18.2 vs. 80.6±20.2 U/L, t=2.389, P=0.019), standard deviation of normal-to-normal RR intervals (126.5±35.9 vs. 143.3±36.4 ms, t=2.320, P=0.022), ejection time (276.9±50.8 vs. 313.8±48.9 ms, t=3.641, P=0.001) and heart rate variability triangle index (37.1±12.9 vs. 41.9±11.1, t=2.020, P=0.047) were significantly lower. Using the Lake Louise Score as the dependent variable, prediction equation were established to estimate AMS: Lake Louise Score=3.783+0.281×eosinophil-0.219×alkaline phosphatase+0.032×PNN50. Conclusions We elucidated the differences of physiological variables as well as noninvasive cardiovascular indicators for subjects after high altitude exposure compared with those at sea level. We also created an acute high altitude reaction early warning equation based on the physiological variables and noninvasive cardiovascular indicators at sea level.

Prophylactic Use of Mucosal Protective Agents and Proton Pump Inhibitors in Patients Undergoing Percutaneous Coronary Intervention: Real World Evidences of 36,870 Patients.

BACKGROUND: Prophylactic medications are believed to reduce risks of gastrointestinal (GI) bleeding after percutaneous coronary intervention (PCI). However, their true effectiveness in preventing GI bleeding is still unknown. METHODS: The clinical data of 36,870 patients treated with PCI from January 2010 to July 2017 were retrospectively analyzed. The trend in the prophylactic use of mucosal protective agents and proton pump inhibitors was analyzed. RESULTS: A total of 36,870 patients were included with a mean age of 60 ± 18 years. In patients treated with primary PCI for ST-segment elevation myocardial infarction, prophylactic medications were associated with a significantly lower incidence of postprocedure GI bleeding in comparison with no medication (1.072%, 52/4852 vs. 2.747%, 25/910; P < 0.001). In patients with CRUSADE scores >40, prophylactic medications were associated with a significantly lower incidence of postprocedure GI bleeding in comparison with not using prophylactic medications (0.679%, 21/3093 vs. 1.899%, 20/1053; P = 0.001). CONCLUSIONS: Prophylactic medications were associated with significantly lower incidence of postprocedure 30-day GI bleeding in patients with primary PCI for ST-segment elevation myocardial infarction or CRUSADE scores >40.

Validation of Single Centre Pre-Mobile Atrial Fibrillation Apps for Continuous Monitoring of Atrial Fibrillation in a Real-World Setting: Pilot Cohort Study.

BACKGROUND: Atrial fibrillation is the most common recurrent arrhythmia in clinical practice, with most clinical events occurring outside the hospital. Low detection and nonadherence to guidelines are the primary obstacles to atrial fibrillation management. Photoplethysmography is a novel technology developed for atrial fibrillation screening. However, there has been limited validation of photoplethysmography-based smart devices for the detection of atrial fibrillation and its underlying clinical factors impacting detection. OBJECTIVE: This study aimed to explore the feasibility of photoplethysmography-based smart devices for the detection of atrial fibrillation in real-world settings. METHODS: Subjects aged ≥18 years (n=361) were recruited from September 14 to October 16, 2018, for screening of atrial fibrillation with active measurement, initiated by the users, using photoplethysmography-based smart wearable devices (ie, a smart band or smart watches). Of these, 200 subjects were also automatically and periodically monitored for 14 days with a smart band. The baseline diagnosis of "suspected" atrial fibrillation was confirmed by electrocardiogram and physical examination. The sensitivity and accuracy of photoplethysmography-based smart devices for monitoring atrial fibrillation were evaluated. RESULTS: A total of 2353 active measurement signals and 23,864 periodic measurement signals were recorded. Eleven subjects were confirmed to have persistent atrial fibrillation, and 20 were confirmed to have paroxysmal atrial fibrillation. Smart devices demonstrated >91% predictive ability for atrial fibrillation. The sensitivity and specificity of devices in detecting atrial fibrillation among active recording of the 361 subjects were 100% and about 99%, respectively. For subjects with persistent atrial fibrillation, 127 (97.0%) active measurements and 2240 (99.2%) periodic measurements were identified as atrial fibrillation by the algorithm. For subjects with paroxysmal atrial fibrillation, 36 (17%) active measurements and 717 (19.8%) periodic measurements were identified as atrial fibrillation by the algorithm. All persistent atrial fibrillation cases could be detected as "atrial fibrillation episodes" by the photoplethysmography algorithm on the first monitoring day, while 14 (70%) patients with paroxysmal atrial fibrillation demonstrated "atrial fibrillation episodes" within the first 6 days. The average time to detect paroxysmal atrial fibrillation was 2 days (interquartile range: 1.25-5.75) by active measurement and 1 day (interquartile range: 1.00-2.00) by periodic measurement (P=.10). The first detection time of atrial fibrillation burden of <50% per 24 hours was 4 days by active measurement and 2 days by periodic measurementThe first detection time of atrial fibrillation burden of >50% per 24 hours was 1 day for both active and periodic measurements (active measurement: P=.02, periodic measurement: P=.03). CONCLUSIONS: Photoplethysmography-based smart devices demonstrated good atrial fibrillation predictive ability in both active and periodic measurements. However, atrial fibrillation type could impact detection, resulting in increased monitoring time. TRIAL REGISTRATION: Chinese Clinical Trial Registry of the International Clinical Trials Registry Platform of the World Health Organization ChiCTR-OOC-17014138; http://www.chictr.org.cn/showprojen.aspx?proj=24191.

Physiological Variables Associated with the Development of Acute Mountain Sickness.

Objective To identify the physiological variables associated with the development of acute mountain sickness (AMS).Methods Eighty four young Chinese men residing at low altitude were taken to an altitude of 4000 m within 40 hours. At sea level and at high altitude, we measured the heart rate, blood pressure, and peripheral oxygen saturation (SpO2) respectively. We also collect blood samples from each participants before and after the altitude elevation. The blood routine and biochemical examinations were performed for all blood samples. The revised Lake Louise Criteria was adopted to diagnose AMS after the subjects arrived at the target high altitude. The association between the presence of AMS and subjects' physiological variables were analysed statistically.Results Of 84 participants, 34 (40.5%) developed AMS. Compared with non AMS group, in the AMS group, the percentage of neutrophils was significantly higher (64.5%±11.2% vs. 58.1%±8.8%, P =0.014), while the level of SpO2 was significantly lower (79.4%±5.4% vs. 82.7%±5.6, P=0.008). Binary logistic regression analyses emphasized the association of neutrophils (OR: 1.06, 95% CI: 1.01-1.12, P=0.034) and SpO2 level (OR: 0.87, 95% CI : 0.79-0.95, P=0.004) with the development of AMS.Conclusion The ability to sustain SpO2 after altitude elevation and the increase of neutrophils were associated with the development of AMS in young males.

Melatonin Attenuates Myocardial Ischemia/Reperfusion Injury by Inhibiting Autophagy Via an AMPK/mTOR Signaling Pathway.

BACKGROUND/AIMS: Melatonin has been demonstrated to protect cardiac microvascular endothelial cells (CMECs) against ischemia/reperfusion injury (IRI). Autophagy plays different roles in the heart during ischemia and reperfusion. The AMP activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) pathway is associated with autophagy. This study sought to explore whether melatonin regulates CMEC autophagy through the AMPK/mTOR signaling pathway. METHODS: The effects of melatonin in IRI were investigated in vivo rat models and in vitro neonatal CMECs. Myocardial infarct size was achieved by Evans blue and triphenyltetrazolium chloride staining. The severity of cell injury was evaluated by cell vitality and lactate dehydrogenase (LDH) release assays, and autophagy was evaluated by transmission electron microscopy and the assessment of autophagy-related gene expression, such as that of Beclin 1 and light chain 3-II. RESULTS: In vivo, melatonin markedly reduced infarcted area, improved cardiac function and decreased LDH release. However, the AMPK activator AICAR and the mTOR inhibitor rapamycin reduced the protective effects of melatonin on IRI. In vitro, Beclin1 and light chain 3-II protein were found to be down-regulated and autophagosomes were found to be reduced in response to melatonin, together with an increase in cell vitality and a decrease in LDH. Treatment with AICAR or rapamycin ablated the benefit observed with melatonin treatment. CONCLUSIONS: Melatonin played an important and protective role in CMECs by inhibiting autophagy against IRI via the AMPK/mTOR system.

Activation of aldehyde dehydrogenase 2 slows down the progression of atherosclerosis via attenuation of ER stress and apoptosis in smooth muscle cells.

Aldehyde dehydrogenase 2 (ALDH2) is a key mitochondrial enzyme in the metabolism of aldehydes and may have beneficial cardiovascular effects for conditions such as cardiac hypertrophy, heart failure, myocardial I/R injury, reperfusion, arrhythmia, coronary heart disease and atherosclerosis. In this study we investigated the role of ALDH2 in the progression of atherosclerosis and the underlying mechanisms, with a focus on endoplasmic reticulum (ER) stress. A clinical study was performed in 248 patients with coronary heart disease. The patients were divided into two groups according to their ALDH2 genotype. Baseline clinical characteristics and coronary angiography were recorded, and the coronary artery Gensini score was calculated. Serum levels of 4-hydroxy-2-nonenal (4-HNE) were detected. The clinical study revealed that the mutant ALDH2 genotype was an independent risk factor for coronary heart disease. ALDH2 gene polymorphism is closely associated with atherosclerosis and the severity of coronary artery stenosis. Serum levels of 4-HNE were significantly higher in patients with the mutant ALDH2 genotype than in patients with the wild-type ALDH2 genotype. As an in vitro model of atherosclerosis, rat smooth muscle cells (SMCs) were treated with oxygenized low-density lipoprotein (ox-LDL), which significantly elevated the levels of ER markers glucose-regulated protein78 (GRP78), protein kinase R-like ER kinase (PERK), phosphorylated eukaryotic translation initiation factor α subunit (p-eIF2α), activating transcription factor-4 (ATF-4), CEBP homologous protein (CHOP) and 4-HNE in the cells. All the ox-LDL-induced responses were significantly attenuated in the presence of Alda-1 (an ALDH2 activating agent), and accentuated in the presence of daidzin (an ALDH2 inhibitor). Furthermore, pretreatment with ALDH2 activator Alda-1 significantly decreased ox-LDL-induced apoptosis. Similarly, overexpression of ALDH2 protected SMCs against ox-LDL-induced ER stress as well as ER stress-induced apoptosis. These findings suggest that ALDH2 may slow the progression of atherosclerosis via the attenuation of ER stress and apoptosis in smooth muscle cells.

Clinical, Laboratory and Imaging Features of High Altitude Pulmonary Edema in Tibetan Plateau.

Objective To analyze characteristics of high altitude pulmonary edema (HAPE) in Chinese patients.Methods We performed a retrospective study of 98 patients with HAPE. We reviewed the medical records and summarized the clinical, laboratory and imaging characteristics of these cases, and compared the results on admission with those determined before discharge.Results Forty-eight (49.0%) patients developed HAPE at the altitude of 2800 m to 3000 m. Ninty-five (96.9%) patients were man. Moist rales were audible from the both lungs, and moist rales over the right lung were clearer than those over the left lung in fourteen patients. The white blood cells [(12.83±5.55) versus (8.95±3.23) ×10 9/L, P=0.001)] as well as neutrophil counts [(11.34±3.81) versus (7.49±2.83)×10 9/L, P=0.001)] were higher, whereas the counts of other subsets of white blood cells were lower on admission than those after recovery (all P<0.05). Serum levels of alkaline phosphatase (115.8±37.6 versus 85.7±32.4 mmol/L, P=0.020), cholinesterase (7226.2±1631.8 versus 6285.3±1693.3 mmol/L, P=0.040), creatinine (85.2±17.1 versus75.1±12.8 mmol/L, P=0.021), uric acid (401.9±114.2 versus 326.0±154.3 mmol/L, P=0.041), and uric glucose (7.20±1.10 versus 5.51±1.11 mmol/L, P=0.001) were higher, but carbondioxide combining power (CO2CP, 26.7±4.4 versus 28.9±4.5 mmol/L, P=0.042) and serous calcium (2.32±0.13 versus 2.41±0.10 mmol/L, P=0.006) were lower on admission. Arterial blood gas results showed hypoxemia and respiratory alkalosis on admission. Conclusions In the present research, men were more susceptible to HAPE than women, and in the process of HAPE, the lesions of the right lung were more serious than those of the left lung. Some indicators of routine blood test and blood biochemistry of HAPE patients changed.

Prognostic value of plasma DPP4 activity in ST-elevation myocardial infarction.

BACKGROUND: Dipeptidyl peptidase-4 (DPP4) regulates blood glucose levels and inflammation, and it is also implicated in the pathophysiological process of myocardial infarction (MI). Plasma DPP4 activity (DPP4a) may provide prognostic information regarding outcomes for ST-segment elevation MI (STEMI) patients. METHODS: Blood samples were obtained from 625 consecutively admitted, percutaneous coronary intervention-treated STEMI patients with a mean age of 57 years old. DPP4a was quantified using enzymatic assays. RESULTS: The median follow-up period was 30 months. Multivariate Cox-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase of DPP4a did not associate with risks of major adverse cardiac or cerebrovascular events (MACCE), cardiovascular mortality, MI, heart failure readmission, stroke, non-cardiovascular mortality and repeated revascularization. However, in a subset of 149 diabetic STEMI patients, DPP4a associated with an increased risk of MACCE (HR 1.16; 95% CI 1.04-1.30; p = 0.01). CONCLUSIONS: DPP4a did not associate with cardiovascular events and non-cardiovascular mortality in non-diabetic STEMI patients. However, DPP4a may be associated with future MACCE in diabetic STEMI patients. Trial registration NCT03046576, registered on 5 February, 2017, retrospectively registered.

Development and validation of clinical risk score to predict the cardiac rupture in patients with STEMI.

BACKGROUND: Cardiac rupture (CR) is a fatal complication of ST-elevation myocardial infarction (STEMI) with poor prognosis. The aim of this study was to develop and validate practical risk score to predict the CR after STEMI. METHODS: A total of 11,234 STEMI patients from 7 centers in China were enrolled in our study, we firstly developed a simplified fast-track CR risk model from 7455 STEMI patients, and then prospectively validated the CR risk model using receiver-operating characteristic (ROC) curves by the other 3779 consecutive STEMI patients. This trial is registered with ClinicalTrials.gov, number NCT02484326. RESULTS: The incidence of CR was 2.12% (238/11,234), and the thirty-day mortality in CR patients was 86%. We developed a risk model which had 7 independent baseline clinical predictors (female sex, advanced age, anterior myocardial infarction, delayed admission, heart rate, elevated white blood cell count and anemia). The CR risk score system differentiated STEMI patients with incidence of CR ranging from 0.2% to 13%. The risk score system demonstrated good predictive value with area under the ROC of 0.78 (95% CI 0.73-0.84) in validation cohort. Primary percutaneous coronary intervention decreased the incidence of CR in high risk group (3.9% vs. 6.2%, p<0.05) and very high risk group (8.0% vs. 15.2%, p<0.05). CONCLUSIONS: A simple risk score system based on 7 baseline clinical variables could identify patients with high risk of CR, for whom appropriate treatment strategies can be implemented.

Mechanisms of protection against diabetes-induced impairment of endothelium-dependent vasorelaxation by Tanshinone IIA.

BACKGROUND: Impairment of endothelium-dependent vasorelaxation has been suggested to play a principle role of endothelial dysfunction in the development of cardiovascular complications of diabetes. Recent studies have demonstrated a protective effect of Tanshinone IIA (Tan) on endothelial nitric oxide synthase (eNOS)-NO pathway. However, its role in endothelium-dependent vasorelaxation in diabetes and precise mechanisms remain elusive. METHODS: Sprague-Dawley rats were injected intraperitoneally with streptozotocin (STZ) to induce diabetes and then administered orally with Tan for 2 weeks. For the in vitro study, human umbilical vein endothelial cells (HUVECs) were co-incubated with Tan and high glucose for 48 h. RESULTS: eNOS expression and NO generation were significantly decreased in diabetic rats. These decreases were accompanied by an impairment of endothelium-dependent relaxation. Administration of Tan ameliorated the aberrant changes in eNOS expression, NO generation and endothelium-dependent relaxation in diabetic rats. Expectedly, Tan also inhibited high glucose-induced decrease of eNOS expression and NO generation in a concentration-dependent manner in HUVECs. Mechanistically, high glucose attenuated eNOS transcriptional activity through inhibiting the binding activity and nuclear translocation of Sp1 and AP-1. However, Tan did not prevent these effects. At post-transcriptional level, Tan increased eNOS expression and activity through multiple mechanisms including regulation of mRNA and protein half-life, degradation, coupling and serine 1177 phosphorylation. Rather than affecting protein phosphatase 2A (PP2A) expression and activity, Tan markedly inhibited the translocation of PP2A-A from cytosol to membrane and subsequently impaired PP2A-A/eNOS interaction, leading to prevent eNOS dephosphorylation. All these alterations underlie the protective role of Tan on eNOS expression following high glucose stimulation. CONCLUSIONS: Our data demonstrate that high glucose decreases eNOS expression initiating at a transcriptional level, whereas Tan prevents such effect through multiple ways of post-transcriptional mechanism. GENERAL SIGNIFICANCE: Our work provided novel mechanisms for Tan in regulating vasorelaxation and may help to better understand the cardiovascular protective action of Tan.

Nicorandil attenuates carotid intimal hyperplasia after balloon catheter injury in diabetic rats.

BACKGROUND: Diabetic patients suffer from undesired intimal hyperplasia after angioplasty. Nicorandil has a trend to reduce the rate of target lesion revascularization. However, whether nicorandil inhibits intimal hyperplasia and the possible mechanisms underlying it remain to be determined. We aimed at assessing the effect of nicorandil on intimal hyperplasia in diabetic rats. METHODS: After intraperitoneal injection of streptozotocin (STZ, 50 mg/kg), balloon injury model was established in carotid arteries of diabetic rats. Rats were randomized to vehicle, nicorandil (15 mg/kg/day) or 5-hydroxydecanoate (5-HD, 10 mg/kg/day), a mitochondrial ATP-sensitive potassium channel (mitoKATP channel)-selective antagonist. Perivascular delivery of εPKC siRNA was conducted to determine the role of εPKC pathway in intimal hyperplasia. In hyperglycemia environment (25 mM glucose), primary culture of vascular smooth muscle cells (VSMCs) were treated with nicorandil or 5-HD. Cell proliferation and cell migration were analyzed. RESULTS: Intimal hyperplasia significantly increased 14 days after balloon injury in diabetic rats (p < 0.01). Nicorandil inhibited intima development, reduced inflammation and prevented cell proliferation in balloon-injured arteries (p < 0.01). The protective effects of nicorandil were reversed by 5-HD (p < 0.05). εPKC was activated in balloon-injured arteries (p < 0.01). Nicorandil inhibited εPKC activation by opening mitoKATP channel. Perivascular delivery of εPKC siRNA inhibited intimal hyperplasia, inflammation and cell proliferation (p < 0.01). High glucose-induced VSMCs proliferation and migration were inhibited by nicorandil. εPKC activation induced by high glucose was also inhibited by nicorandil and that is partially reversed by 5-HD. εPKC knockdown prevented VSMCs proliferation and migration (p < 0.01). CONCLUSIONS: Our study demonstrates that nicorandil inhibits intimal hyperplasia in balloon-injured arteries in diabetic rats. Nicorandil also prevents VSMCs proliferation and migration induced by high glucose. The beneficial effect of nicorandil is conducted via opening mitoKATP channel and inhibiting εPKC activation.

Endothelial Cell Autophagy in Atherosclerosis is Regulated by miR-30-Mediated Translational Control of ATG6.

BACKGROUND/AIMS: Endothelial cell injury and subsequent death play an essential role in the pathogenesis of atherosclerosis. Autophagy of endothelial cells has a protective role against development of atherosclerosis, whereas the molecular regulation of endothelial cell autophagy is unclear. MicroRNA-30 (miR-30) is a known autophagy suppressor in some biological processes, while it is unknown whether this regulatory axis may be similarly involved in the development of atherosclerosis. Here, we aimed to answer these questions in the current study. METHODS: We examined the levels of endothelial cell autophagy in ApoE (-/-) mice suppled with high-fat diet (HFD), a mouse model for atherosclerosis (simplified as HFD mice). We analyzed the levels of autophagy-associated protein 6 (ATG6, or Beclin-1) and the levels of miR-30 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-30 and 3'-UTR of ATG6 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-30 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs). RESULTS: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/-) mice that had received normal diet (simplified as NOR mice) did not. Compared to NOR mice, HFD mice had significantly lower levels of endothelial cell autophagy, resulting from decreases in ATG6 protein, but not mRNA. The decreases in ATG6 in endothelial cells were due to HFD-induced increases in miR-30, which suppressed the translation of ATG6 mRNA via 3'-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. CONCLUSION: Upregulation of miR-30 by HFD may impair the protective effects of endothelial cell autophagy against development of atherosclerosis through suppressing protein translation of ATG6.

Atherosclerosis-Associated Endothelial Cell Apoptosis by MiR-429-Mediated Down Regulation of Bcl-2.

BACKGROUND/AIMS: Endothelial cell injury and subsequent apoptosis play a key role in the development and pathogenesis of atherosclerosis, which is hallmarked by dysregulated lipid homeostasis, aberrant immunity and inflammation, and plaque-instability-associated coronary occlusion. Nevertheless, our understanding of the mechanisms underlying endothelial cell apoptosis is still limited. MicroRNA-429 (miR-29) is a known cancer suppressor that promotes cancer cell apoptosis. However, it is unknown whether miR-429 may be involved in the development of atherosclerosis through similar mechanisms. We addressed these questions in the current study. METHODS: We examined the levels of endothelial cell apoptosis in ApoE (-/-) mice suppled with high-fat diet (HFD), a mouse model for atherosclerosis (simplified as HFD mice). We analyzed the levels of anti-apoptotic protein Bcl-2 and the levels of miR-429 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-429 and 3'-UTR of Bcl-2 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-429 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs). RESULTS: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/-) mice that had received normal diet (simplified as NOR mice) did not. HFD mice had significantly lower percentage of endothelial cells and significantly higher percentage of mesenchymal cells in the aorta than NOR mice. Significantly higher levels of endothelial cell apoptosis were detected in HFD mice, resulting from decreases in Bcl-2 protein, but not mRNA. The decreases in Bcl-2 in endothelial cells were due to increased levels of miR-429, which suppressed the translation of Bcl-2 mRNA via 3'-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. CONCLUSION: Atherosclerosis-associated endothelial cell apoptosis may result from down regulation of Bcl-2, through increased miR-429 that binds and suppresses translation of Bcl-2 mRNA.

Effects of liraglutide on left ventricular function in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

BACKGROUND: Several studies have shown that exenatide protects against ischemia-reperfusion injury and improves cardiac function in patients with acute ST-segment elevation myocardial infarction (STEMI). The effects of liraglutide, a glucagon-like peptide-1 analogue, on STEMI patients remain unclear. We planned to evaluate the effects of liraglutide on left ventricular function after primary percutaneous coronary intervention for STEMI. METHODS: A total of 92 patients were randomized 1:1 to receive either liraglutide or placebo for 7 days. Study treatment was commenced 30 minutes before intervention (1.8 mg) and maintained for 7 days after the procedure (0.6 mg for 2 days, 1.2 mg for 2 days, followed by 1.8 mg for 3 days). Eighty-five patients completed the trial. Transthoracic echocardiography was used to assess left ventricular function. RESULTS: At 3 months, the primary end point, a difference in change of left ventricular ejection fraction between the two groups was +4.1% (95% CI +1.1% to +6.9%) (P < .001). There was a tendency for a lower rate of no-reflow in liraglutide group that did not reach statistical significance (7% vs control group 15%, P = .20). Liraglutide could significantly improve stress hyperglycemia (P < .05). In addition, liraglutide elicited favorable changes in markers of inflammation and endothelial function. CONCLUSION: A short 7-day course of liraglutide in STEMI patients treated with primary percutaneous coronary intervention is associated with mild improvement in left ventricular ejection fraction at 3 months.

The difference between Asian and Western in the effect of LDL-C lowering therapy on coronary atherosclerotic plaque: a meta-analysis report.

BACKGROUND: The different effects of LDL-C levels and statins therapy on coronary atherosclerotic plaque between Western and Asian remain to be settled. METHODS: PubMed, EMBASE, and Cochrane databases were searched from Jan. 2000 to Sep. 2014 for randomized controlled or blinded end-points trials assessing the effects of LDL-C lowering therapy on regression of coronary atherosclerotic plaque (CAP) in patients with coronary heart disease by intravascular ultrasound. The significance of plaques regression was assessed by computing standardized mean difference (SMD) of the volume of CAP between the baseline and follow-up. RESULTS: Twenty trials (ten in the West and ten in Asia) were identified. For Westerns, Mean lowering LDL-C by 49.4% and/or to level 61.9 mg/dL in the group of patients with baseline mean LDL-C 123.2 mg/dL could significantly reduce the volume of CAP at follow up (SMD -0.156 mm(3), 95% CI -0.248 ~ -0.064, p = 0.001). LDL-C lowering by rosuvastatin (mean 40 mg daily) could significantly decrease the volumes of CAP at follow up. For Asians, Mean lowering LDL-C by 36.1% and/or to level 84.0 mg/dL with baseline mean LDL-C 134.2 mg/dL could significantly reduce the volume of CAP at follow up (SMD -0.211 mm(3), 95% CI -0.331 ~ -0.092, p = 0.001). LDL-C lowering by rosuvastatin (mean 14.1 mg daily) and atorvastatin (mean 18.9 mg daily) could significantly decrease the volumes of CAP at follow up. CONCLUSIONS: There was a different effect of LDL-C lowering on CAP between Westerns and Asians. For regressing CAP, Asians need lower dosage of statins or lower intensity LDL-C lowering therapy than Westerns.

Associations between plasma total homocysteine, blood pressure stages and pulse wave velocity in Chinese rural community population.

The aim of the study was to examine the associations among plasma total homocysteine (tHcy) and blood pressure (BP) stages and brachial-ankle pulse wave velocity (ba-PWV) in a Chinese rural community population. In this cross-sectional study, 2148 rural community subjects with normotension and mild hypertension (HTN) were classified into four groups according to ba-PWV level. Multivariate regression showed that ba-PWV was significantly and independently correlated with tHcy (ß = 5.32, p < 0.001) in the entire study population. Moreover, ba-PWV showed a significant increase with increasing plasma tHcy level in subjects with both high normal BP and grade 1 HTN (p < 0.05). Compared with optimal BP stage, ba-PWV was significantly associated with high normal BP stage (ß = 193, p < 0.001) and grade 1 HTN (ß = 413, p < 0.001).There was a statistical interaction effect between high normal BP stage and optimal BP stage (p = 0.045). The similar result was found between subjects with optimal BP and those with grade 1 HTN (p = 0.037). In conclusion, tHcy was independently correlated with ba-PWV in subjects with high normal BP and grade 1 HTN. High normal BP and grade 1 HTN may worsen the impact of tHcy on arterial stiffness in a Chinese rural community population.