Comprehensive mendelian randomization reveals atrial fibrillation-breast cancer relationship and explores common druggable targets.

Background: Atrial fibrillation (AF) and breast cancer pose significant risks to human health. The reasons behind the concurrent occurrence of AF and breast cancer remain unclear, leading to complex treatment approaches. Mendelian Randomization (MR) analyses aim to offer genetic evidence supporting the causation of AF and breast cancer and to investigate common druggable genes associated with both conditions. Methods: We used two-samples of MR to sequentially explore the causal relationship between atrial fibrillation and breast cancer, and between atrial fibrillation and breast cancer therapeutic drugs, and verified the stability of the results through colocalization analysis. We utilized the Connectivity map database to infer the direction of drug effects on disease. Finally, we explored druggable genes that play a role in AF and breast cancer and performed a Phenome-wide MR analysis to analyze the potential side effects of drug targets. Results: We found 15 breast cancer therapeutic drugs that significantly support a causal association between AF and breast cancer through expression in blood and/or atrial appendage tissue. Among these, activation of ANXA5 by Docetaxel, inhibition of EIF5A by Fulvestrant, and inhibition of GNA12 by Tamoxifen increased the risk of AF, while inhibition of ANXA5 by Gemcitabine and Vinorebine and inhibition of PCGF6 by Paclitaxel reduced the risk of AF. Inhibition of MSH6 and SF3B1 by Cyclophosphamide, as well as inhibition of SMAD4 and PSMD2 and activation of ASAH1 and MLST8 by Doxorubicin can have bidirectional effects on AF occurrence. XBP1 can be used as a common druggable gene for AF and breast cancer, and there are no potential side effects of treatment against this target. Conclusion: This study did not find a direct disease causality between AF and breast cancer but identified 40 target genes for 15 breast cancer therapeutic drugs associated with AF, clarified the direction of action of 8 breast cancer therapeutic drugs on AF, and finally identified one common druggable target for AF and breast cancer.

The Noninvasive Sonothermogenetics Used for Neuromodulation in M1 Region of Mice Brain by Overexpression of TRPV1.

Sonogenetics is preferred for neuroregulation and the treatment of brain diseases due to its noninvasive properties. Ultrasonic stimulation produces thermal and mechanical effects, among others. Since transient receptor potential vanilloid 1 (TRPV1) could be activated at 42 °C, it is overexpressed in the M1 region of the mouse motor cortex to sense the change of temperature upon being stimulated by focused ultrasound. Whether the heat generated by ultrasonic stimulation could activate TRPV1 in the M1 region and induce changes in electromyography (EMG) signals collected from the mice's triceps was carefully verified. The position of the focused ultrasound and the temperature of the tissue at the location of the focused position were simulated using COMSOL software and verified via experiments. For Neuro-2a cells with TRPV1 overexpression, 42 °C could activate the TRPV1 and induce calcium influx. For mice with TRPV1 overexpression in the M1 region, tissue temperature of >42 °C in the M1 region induces an increased number of cfos, suggesting that neurons with overexpressed TRPV1 in the M1 region can be activated using focused ultrasound. Furthermore, when the temperature is >42 °C, the peak-to-peak value of the EMG signal for mice with TRPV1 overexpression in the M1 region was higher than that for mice without TRPV1 overexpression. The immunohistochemical results showed that ultrasound was not harmful to the stimulation site. The noninvasive ultrasound stimulation combined with thermosensitive protein TRPV1 overexpressed in neurocytes as sonothermogenetics technology has great potential to be used for the treatment of neurological diseases.

Mir-421 and mir-550a-1 are potential prognostic markers in esophageal adenocarcinoma.

OBJECTIVE: To identify the prognostic indicators of esophageal adenocarcinoma (EAC) for future EAC diagnosis and treatment. METHODS: The EAC dataset from The Cancer Genome Atlas was screened for differentially expressed microRNAs (miRNAs) and mRNAs associated with EAC. Weighted gene coexpression network analysis was performed to cluster miRNAs or mRNA with similar expression patterns to identify the miRNAs or mRNA that are highly associated with EAC. Prognostic miRNAs for overall survival (OS) were identified using Cox proportional-hazards regression analysis and least absolute shrinkage and selection operator based on survival duration and status. Two types of miRNAs were selected to develop a prognostic signature model for EAC using multiple Cox regression analysis. Furthermore, the signature was validated using internal validation sets 1 and 2. The receiver operating characteristic curve and concordance index were used to evaluate the accuracy of the signature and validation sets. The expression of miR-421, miR-550a-3p, and miR-550a-5p was assessed using quantitative polymerase chain reaction (qPCR). The proliferation, invasion, and migration of EAC cells were assessed using CCK8 and transwell assays. The OS of target mRNAs was assessed using Kaplan-Meier analysis. Functional enrichment analysis of the target mRNAs was performed using Metascape. RESULTS: The prognostic signature and validation sets comprising mir-421 and mir-550a-1 had favorable predictive power in OS. Compared with the patients with EAC in the high-expression group, those assigned to the low-expression group displayed increased OS according to survival analysis. Differential and qPCR analysis showed that miR-421, miR-550a-3p, and miR-550a-5p were highly expressed in the EAC tissues and cell lines. Moreover, the downregulation of miR-421 and miR-550a-3p with inhibitor markedly suppressed the proliferation, invasion, and migration in OE33 cells compared with the negative control. A total of 20 target mRNAs of three miRNAs were predicted, among which seven target mRNAs-ASAP3, BCL2L2, LMF1, PPM1L, PTPN21, SLC18A2, and NR3C2-had prognostic value; PRKACB, PDCD4, RPS6KA5, and BCL2L2 were enriched in the miRNA cancer pathway. CONCLUSION: Prognostic indicators of EAC may be useful in future EAC diagnosis and treatment.

Doxorubicin inhibits cholesterol efflux through the miR-33/ABCA1 pathway.

Doxorubicin (DOX) is extensively used for the treatment of kinds of cancers, and cardiovascular toxicity is one of the side effects. However, it is unclear whether DOX causes impairment of cardiac function by promoting atherosclerosis. Thus, we investigated the role of DOX in regulating the lipid deposition of macrophages and its molecular mechanism. RAW 264.7 cell line was stimulated with DOX in the presence or absence of low-density lipoprotein (LDL). We found that DOX increased miR-33 and reduced ATP binding cassette transporter A1 (ABCA1) protein. Moreover, cholesterol efflux was suppressed by DOX, which was more efficient under a high-cholesterol condition. After transfecting mimics or inhibitors of miR-33 into cells, ABCA1 protein was respectively decreased and increased, and intracellular lipid accumulation was correspondingly regulated. Overall, DOX suppresses the expression of ABCA1 protein by upregulating miR-33, promoting an intracellular lipid deposition in macrophages, which is a sign of early atherosclerosis. This provides new insights for clinical observation and evaluation of the side effects of DOX.

The relationship between ambulatory arterial stiffness index and left ventricular diastolic dysfunction in HFpEF: a prospective observational study.

BACKGROUND: The relationship between ambulatory arterial stiffness index (AASI) and left ventricular diastolic dysfunction (LVDD) in patients with heart failure with preserved ejection fraction (HFpEF) is unknown. We aimed to investigate the association between the AASI and LVDD in HFpEF. METHODS: We prospective enrolled consecutive patients with HFpEF in Chongqing, China. Twenty-four-hour ambulatory blood pressure monitoring (24 h-ABPM) and echocardiography were performed in each patient. AASI was obtained through individual 24 h-ABPM. The relationship between AASI and LVDD was analyzed. RESULTS: A total of 107 patients with HFpEF were included. The mean age was 68.45 ± 14.02 years and 63 (59%) were women. The patients were divided into two groups according to the upper normal border of AASI (0.55). AASI > 0.55 group were more likely to be older, to have higher mean systolic blood pressure and worsen left ventricular diastolic function than AASI group ≤ 0.55. AASI was closely positive related to the diastolic function parameters, including mean E/e' (r = 0.307, P = 0.001), septal E/e' (r = 0.290, P = 0.002), lateral E/e' (r = 0.276, P = 0.004) and E (r = 0.274, P = 0.004). After adjusting for conventional risk factors, AASI was still an independent risk factors of mean E/e' > 10 in patients with HFpEF (OR: 2.929, 95%CI: 1.214-7.064, P = 0.017), and the association between AASI and mean E/e' > 14 was reduced (OR: 2.457, 95%CI: 1.030-5.860, P = 0.043). AASI had a partial predictive value for mean E/e' > 10 (AUC = 0.691, P = 0.002), while the predictive value for mean E/e' > 14 was attenuated (AUC = 0.624, P = 0.034). CONCLUSION: AASI was positive related to E/e' in HFpEF and might be an independent risk factor for the increase of mean E/e'.

Improved sintering performance of ß-SiAlON-Si3N4 and its osteogenic differentiation ability by adding ß-SiAlON.

To improve the sintering performance of silicon nitride bioceramics, we explored the effect of ß-SiAlON's Z-value on the physical, chemical, and biological properties of ß-SiAlON-Si3N4 composites. Results showed that the phase product was ß-Si3N4. As the Z-value increased, the X-ray diffraction peaks gradually shifted to a smaller angle, the material grains were more tightly packed, and the bulk density and compressive strength increased, reaching the highest values (2.71 g/cm3 and 1157 MPa, respectively) at Z = 4. Soaking and ion-release experiments show that in an aqueous environment, a small amount of Al and Si ions were released, and no obvious decomposition occurred on the surface of the material. The biological performance showed that the growth of cultured cells in each group was in good condition, there was no obvious difference in morphology and adhesion, and the materials had good biological performance. An increase in the Z-value promotes the formation of mineralized nodules and osteogenic differentiation of MC3T3-E1 cells, which may be because the release of Si can promote osteogenic differentiation. Therefore, the addition of ß-SiAlON could improve the sintering performance of ß-Si3N4 without degrading its biological properties. The prepared ß-SiAlON-Si3N4 composite ceramic is a latent bioceramic material.

ST-segment resolution as a marker for severe myocardial fibrosis in ST-segment elevation myocardial infarction.

OBJECTIVE: To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). METHODS: Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (> 75%) or non-transmural (< 75%) myocardial scars, according to previous study. RESULTS: The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.925. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR < 40.15% had a 170.90-fold higher probability of developing transmural scars compared with patients with STR ≥ 40.15%. Pearson correlation and linear regression analyses showed STR percentage was significantly associated with myocardial scar thickness and size. CONCLUSION: STR < 40.15% at 24 h after PCI may provide meaningful diagnostic information regarding the extent of myocardial scarification in STEMI patients.

TNAP is a novel regulator of cardiac fibrosis after myocardial infarction by mediating TGF-ß/Smads and ERK1/2 signaling pathways.

BACKGROUND: Cardiac fibrosis is the most important pathogenesis leading to cardiac remodeling and heart failure after myocardial infarction (MI). Tissue nonspecific alkaline phosphatase (TNAP) has recently been recognized as a potential prognostic factor for MI. Nevertheless, the role of TNAP in cardiac fibrosis after MI has not been explicitly delineated. METHODS: A systematic review and meta-analysis was conducted to assess the effect of serum TNAP levels on mortality in patients with ischemic heart disease (IHD). A correlation analysis was performed to investigate the relationship between serum levels of TNAP and biomarkers of fibrosis. Heart biopsies from patients with MI and a mouse model of MI were used to detect the expression and distribution of TNAP. Furthermore, we established adenovirus-mediated knockdown and overexpression of TNAP, using a combination of in vivo and in vitro studies in mice, to determine the role and mechanism of TNAP in cardiac fibrosis after MI. In the in vitro studies, cardiac fibroblasts were cultured on soft plates. FINDINGS: After searching the main databases and performing a detailed assessment of the full-text articles, eight studies with 14,816 individuals were included in the quantitative analysis. We found that a high serum TNAP level was associated with an increased risk of mortality in patients with IHD and MI. The correlation analysis revealed a positive correlation between serum TNAP levels and the concentration of fibrosis biomarkers (PICP/PIIINP). The expression of TNAP was upregulated in the myocardium of patients with MI and in a mouse model of MI, accompanied by fibroblast activation and the deposition of collagen fibers. In the in vivo study, TNAP knockdown ameliorated cardiac fibrosis and improved cardiac function in mice. TNAP overexpression aggravated cardiac fibrosis and worsened cardiac function. In the in vitro study, TNAP promoted cardiac fibroblast differentiation, migration and proliferation. Mechanistically, the pro-fibrotic effect of TNAP on cardiac fibroblasts was at least partially achieved by activating the TGF-ß1/Smads and ERK1/2 signaling pathways. INTERPRETATION: Based on these findings, TNAP plays an important pro-fibrotic role in cardiac fibrosis after MI by activating TGF-ß/Smads and ERK1/2 signaling, indicating that it functions as a potential regulator of and therapeutic target in cardiac fibrosis. FUNDING: This work was supported by the National Natural Science Foundation of China.

[Corrigendum] Protective effects of exendin­4 on hypoxia/reoxygenation­induced injury in H9c2 cells.

Following the publication of the above article, the authors noted that an incorrect version of Fig. 8 had been included. Essentially, the data presented as panel (B) in this figure should not have been included; there is only one data panel in this figure. The corrected version of Fig. 8 is shown opposite. Secondly, the authors have realized that, in the main title and in the running title, exendin­4 was incorrectly spelt as "extendin­4". The correct version of the title, as it should have appeared in this paper, is shown above. Note that these errors do not alter the interpretation of the results and conclusions, and all the authors agree to this corrigendum. The authors apologize to the readership of the Journal for any confusion these errors have caused. [the original article was published in Molecular Medicine Reports 12: 3007-3016, 2015; DOI: 10.3892/mmr.2015.3682].

TNAP inhibition attenuates cardiac fibrosis induced by myocardial infarction through deactivating TGF-ß1/Smads and activating P53 signaling pathways.

Tissue nonspecific alkaline phosphatase (TNAP) is expressed widely in different tissues, modulating functions of metabolism and inflammation. However, the effect of TNAP on cardiac fibrosis remains controversial and needs to be further studied. The present study aims to investigate the role of TNAP on myocardial infarction (MI)-induced fibrosis and its mechanism. TNAP was upregulated in patients with MI, both in serum and injured hearts, and predicted in-hospital mortality. TNAP was also significantly upregulated after MI in rats, mostly in the border zone of the infarcted hearts combined with collagen synthesis. Administration of TNAP inhibitor, tetramisole, markedly improved cardiac function and fibrosis after MI. In the primary cultures of neonatal rat cardiac fibroblasts (CFs), TNAP inhibition significantly attenuated migration, differentiation, and expression of collagen-related genes. The TGF-ß1/Smads signaling suppression, and p-AMPK and p53 upregulation were involved in the process. When p53 inhibitor was administered, the antifibrotic effect of TNAP inhibition can be blocked. This study provides a direct evidence that inhibition of TNAP might be a novel regulator in cardiac fibrosis and exert an antifibrotic effect mainly through AMPK-TGF-ß1/Smads and p53 signals.

DNA hydroxymethylation combined with carotid plaques as a novel biomarker for coronary atherosclerosis.

Little is known about the diagnostic value of DNA methylation and hydroxymethylation for coronary atherosclerosis. Carotid plaque is a common marker for coronary atherosclerosis. Our aim is to determine whether DNA methylation and hydroxymethylation combined with carotid plaques can be useful to the diagnosis of coronary atherosclerosis. The 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) levels from peripheral blood mononuclear cells (PBMCs) were measured in 113 enrolled patients. Crouse score and Gensini score were used to evaluate the severity of carotid and coronary atherosclerosis, respectively. With the increasing of severity of carotid plaque, a stepwise upward trend was observed in 5-mC and 5-hmC levels from PBMCs, which were significantly correlated with the risk factors, Crouse score and Gensini score. Crouse score and 5-hmC, not 5-mC, were the risk factors for coronary atherosclerosis after adjustment for the risk factors (the history of diabetes, FPG and HbA1c). Receiver operating characteristic (ROC) analysis indicated that 5-hmC combined with Crouse score was the diagnostic biomarker for coronary atherosclerosis, with the highest areas under the curve (AUC) for 0.980 (0.933-0.997), valuable sensitivity for 96.23% and specificity for 91.67%. These findings suggest 5-hmC level combined with Crouse score may provide the meaningful information for coronary atherosclerosis diagnosis.

DNA methylation and hydroxymethylation are associated with the degree of coronary atherosclerosis in elderly patients with coronary heart disease.

AIMS: DNA methylation and hydroxymethylation are significantly related to the occurrence and development of coronary heart disease (CHD) and atherosclerosis (AS). 5-Methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) are used to assess DNA methylation and hydroxymethylation levels, respectively. However, 5-mC and 5-hmC levels associated with CHD remain controversial. In the present study, we aimed to investigate the association of the peripheral blood levels of 5-mC and 5-hmC and the degree of coronary atherosclerosis in elderly CHD patients. MAIN METHODS: 5-mC and 5-hmC levels in peripheral blood mononuclear cells (PBMCs) were measured in 44 CHD patients and 42 matched control subjects by ELISA and dot blot analysis. Immunohistochemical staining was used to observe 5-mC, 5-hmC and TET2 expression in human aortic tissue. Gensini score was used to evaluate the degree of coronary atherosclerosis. KEY FINDINGS: 5-mC and 5-hmC levels in PBMCs from CHD patients and in human aortic atherosclerosis plaque were both higher than those in control subjects and in tissue samples. TET2 expression was significantly upregulated in CHD patients compared with control subjects, while only an increasing trend in the expression of DNMT1, DNMT3A and all the other TET genes were found. Spearman correlation analysis demonstrated that 5-mC and 5-hmC levels were positively correlated with Gensini score. 5-mC and 5-hmC were considered as the risk factors for CHD after adjustment. SIGNIFICANCE: DNA methylation and hydroxymethylation levels in PBMCs from elderly CHD patients were significantly increased, showing a positive correlation with the degree of coronary atherosclerosis.

Factors that contribute to poor adherence to statin therapy in coronary heart disease patients from Chongqing and measures to improve their therapeutic outcomes.

To assess the efficacy and short-term outcomes of adherence to statin therapy among coronary heart disease (CHD) patients following their hospital discharge, we enrolled 615 CHD patients who were prescribed statins from The First Affiliated Hospital of Chongqing Medical University in China between February 1st and October 31st of 2013. Statin adherence was evaluated by identifying the proportion of patients who remained adherent or became non-adherent to statin therapy over 4-8 months post-discharge from the hospital. The composite outcomes included all-cause mortality and re-hospitalization with cardiovascular disease. We found that 15.9% patients were non-adherent to their statin therapies and that coronary artery stenosis<75% (OR = 3.433, 95% CI: 2.191-5.380, p < 0.001) and adverse effects (OR = 2.542, 95% CI: 1.327-4.869, p = 0.005) both clearly contributed to poor adherence. The primary self-reported reasons for non-adherence included a lack of knowledge about the benefits of statin therapy (36.7%), the treatment being halted at the advice of their doctor (19.4%), and the difficulty in obtaining statins (12.2%). Non-adherence to statin therapy was significantly associated with an increased risk of cardiovascular events (OR = 1.741, 95% CI: 1.035-2.929, p = 0.037). In conclusion, CHD patients with moderate stenosis or adverse effects tended to have poor statin adherence, and this was significantly associated with increased cardiovascular events. We should strengthen education of the importance of statin therapy for both patients and doctors and facilitate the ability of patients to obtain their statin medication. Clinical Study Register Code: ChiCTR-EPC-16007839.

Trimetazidine protects against myocardial ischemia/reperfusion injury by inhibiting excessive autophagy.

Trimetazidine (TMZ) has been demonstrated to have protective effects against myocardial ischemia/reperfusion (MI/R) injury. In the present study, we investigated the effects and the underlying mechanisms of TMZ on autophagy during MI/R in vivo and in vitro. In the in vivo study, an animal model of MI/R was induced by coronary occlusion. TMZ (20 mg/kg/day) protected the rat hearts from MI/R-induced heart failure by increasing ejection fraction and fractional shortening and decreasing end-systolic volume, end-diastolic volume, left ventricular (LV) internal diameter at systole, and LV internal diameter at diastole; it alleviated myocardial injury and oxidative stress by decreasing LDH, creatine kinase MB isoenzyme, ROS, and MDA levels and increasing SOD and glutathione peroxidase levels in plasma. TMZ also reduced myocardial infarct size and apoptosis. Moreover, TMZ markedly inhibited MI/R-induced autophagy by decreasing the protein and messenger RNA levels of LC3-II, Beclin1, ATG5, and ATG7 and the number of autophagosomes and by involving the AKT/mTOR pathway. Further, in the in vitro experiments, H9c2 cells were incubated with TMZ (40 µM) to explore the direct effects of TMZ following exposure to hypoxia and reoxygenation (H/R). TMZ increased cell viability and the concentration of intracellular SOD and inhibited H/R-induced cell apoptosis and ROS production. Moreover, TMZ decreased the number of autophagosomes and autophagy-related protein expression; it also upregulated p-AKT and p-mTOR expression. In addition, TMZ augmented Bcl-2 protein expression and diminished Bax protein expression, the Bax/Bcl-2 rate, and cleaved caspase-3 level. However, these effects on H9c2 cells were notably abolished by the PI3K inhibitor LY294002. In conclusion, our results showed that TMZ inhibited I/R-induced excessive autophagy and apoptosis, which was, at least partly, mediated by activating the AKT/mTOR pathway. KEY MESSAGES: TMZ improved cardiac function, alleviated myocardial injury and oxidative stress, and reduced the myocardial infarct area and apoptosis. TMZ inhibited MI/R-induced myocardial autophagy, H/R-induced H9c2 cell apoptosis, and autophagy flux. The effect of TMZ on autophagy was repressed by LY294002. TMZ protected against MI/R injury by inhibiting excessive autophagy via activating the AKT/mTOR pathway.

Vangl2 is essential for myocardial remodeling activated by Wnt/JNK signaling.

The Wnt/JNK pathway, responsible for tissue polarity in cardiogenesis in vertebrates, has been shown to play numerous roles during differentiation and development of cardiac myocytes. Van Gogh-like-2 (Vangl2) is a core component that regulates the induction of polarized cellular and tissue morphology during animal development. However, little is known about Wnt/JNK signaling pathway in the process of myocardial remodeling. In present study, we found that activation of Wnt/JNK signaling by Wnt5a stimulates enlargement of cardiomyocyte surface area. The hypertrophic features were inhibited in Vangl2 depleted cells. Meanwhile, Wnt/JNK activation induced cytoskeleton rearrangement but failed to activate these effects in cells lacking Vangl2. Moreover, Wnt/JNK activation significantly increased the cell apoptosis by mediating the mitochondrial permeability transition pore (mPTP) dysfunction, whereas knockdown of Vangl2 partly reversed these effects. These results suggest that activation of Wnt/JNK signaling stimulates myocardial remodeling (cell morphological changes, apoptosis and mitochondrial dysfunction), in which Vangl2 may play an essential role.

Cardioprotection by exenatide: A novel mechanism via improving mitochondrial function involving the GLP-1 receptor/cAMP/PKA pathway.

Accumulating evidence suggests that glucagon-like peptide-1 (GLP-1) and its analogues exert cardioprotective effects via modulating cardiomyocyte metabolism. Mitochondria play a pivotal role in the regulation of cell metabolism. It was hypothesized that treatment with exenatide, a GLP-1 analogue, may exert cardioprotective effects by improving mitochondrial function in an in vitro model of hypoxia/reoxygenation (H/R). H9c2 cells were employed to establish an in vitro model of H/R. Exenatide was added to the cells for 30 min prior to exposure to hypoxia. The GLP-1 receptor antagonist exendin­(9­39), the cyclic adenosine monophosphate (cAMP) inhibitor Rp-cAMPS and the protein kinase A (PKA) inhibitor H-89 were added to the cells for 10 min prior to treatment with exenatide. The release of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) and cardiomyocyte apoptosis were evaluated. The characteristics of mitochondrial morphology and functions, including ATP synthesis, membrane potential (ΔΨm), mitochondrial permeability transition pore (mPTP), mitochondrial ATPase activity and oxidative stress, were determined. the mitochondrial uncoupling protein-3 (UCP-3) and nuclear respiratory factor-1 (Nrf-1) were also investigated by western blot analysis. Exenatide pretreatment significantly decreased LDH and CK-MB release and cardiomyocyte apoptosis in H9c2 cells subjected to H/R. More importantly, to the best of our knowledge, this is the first report of exenatide pretreatment decreasing mitochondrial abnormalities and reducing oxidative stress, while enhancing ATP synthesis, mitochondrial ATPase activity and ΔΨm in H9c2 cells subjected to H/R. Exenatide pretreatment also decreased mitochondrial calcium overload and inhibited the opening of mPTP in H9c2 cells subjected to H/R. Furthermore, exenatide pretreatment upregulated UCP-3 and Nrf-1 expression in H9c2 cells subjected to H/R. However, the abovementioned observed effects of exenatide were all abolished when exenatide was co-administered with exendin­(9­39), Rp-cAMPS and̸or H-89. Therefore, the GLP-1 analogue exenatide was found to exert cardioprotective effects in an in vitro model of H/R, and this cardioprotection may be attributed to the improvement of mitochondrial function. These effects are most likely associated with the activation of the GLP-1 receptor/cAMP/PKA signaling pathway.

Comparative evaluation of copeptin and NT-proBNP in patients with severe acute decompensated heart failure, and prediction of adverse events in a 90-day follow-up period: A prospective clinical observation trial.

The present study compared the prognostic value of a marker, the C-terminal section of the arginine vasopressin prohormone (copeptin), with N-terminal B-type natriuretic peptide (NT-proBNP) in patients with severe acute decompensated heart failure. A prospective, observational cohort study was conducted in a tertiary care hospital and enrolled 129 patients with severe acute decompensated heart failure. Clinicians were blinded to investigational markers except NT-proBNP, and the study participants were followed up for 90 days. The end-point was a composite of cardiovascular death or re-hospitalization due to decompensated heart failure. Of the 129 patients enrolled, 47 reached the end-point and 82 were in a stable condition during follow-up. Receiver operating characteristic curve analysis revealed that the areas under curve for the prediction of adverse events within 90 days were similar for copeptin [0.602±0.052; 95% confidence interval (CI), 0.499-0.705], NT-proBNP (0.659±0.048; 95% CI, 0.565-0.753) and their combination (0.670±0.050; 95% CI, 0.573-0.767). Kaplan-Meier survival analysis showed that the predictive value of NT-proBNP regarding the probability of survival was superior compared with that of copeptin (log-rank test for trend, P=0.001 vs. 0.040). Furthermore, multivariate Cox proportional-hazards regression analysis revealed that increased NT-proBNP and copeptin plasma concentrations were significant independent predictors of adverse events. The present study provided evidence that copeptin has similar predictive properties compared with NT-proBNP regarding adverse events within 90-days in patients with severe acute decompensated heart failure, but that copeptin may not provide superior 90-day prediction compared to NT-proBNP.

15-Lipoxygenase-1 Is Involved in the Effects of Atorvastatin on Endothelial Dysfunction.

Statins exert pleiotropic effects on endothelial cells in addition to lowering cholesterol. 15-Lipoxygenase-1 (ALOX15) has been implicated in vascular inflammation and disease. The relationship between atorvastatin and ALOX15 was investigated using a rat carotid artery balloon-injury model. Hematoxylin and eosin (HE) staining showed that ALOX15 overexpression increased the thickness of the intima-media (IMT). Immunohistochemistry and western blotting showed that atorvastatin increased the expression of cellular adhesion molecules (CAMs) but decreased the expression of endothelial nitric oxide synthase (eNOS); these effects of atorvastatin were blocked by ALOX15 overexpression. In human umbilical venous endothelial cells (HUVECs), silencing of ALOX15 enhanced the effects of atorvastatin on endothelial function. Expression levels of CAMs and Akt/eNOS/NO under oxidized low-density lipoprotein (ox-LDL) stimulation were modulated by ALOX15 inhibitor and ALOX15 small interfering RNA (siRNA). Atorvastatin abolished the activation of nuclear factor-kappa B (NF-κB) induced by ox-LDL. Exposure to ox-LDL induced upregulation of ALOX15 in HUVECs, but this effect was partially abolished by atorvastatin or the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC). These results demonstrate that regulation of ALOX15 expression might be involved in the effects of atorvastatin on endothelial dysfunction.

Geniposide Prevents Hypoxia/Reoxygenation-Induced Apoptosis in H9c2 Cells: Improvement of Mitochondrial Dysfunction and Activation of GLP-1R and the PI3K/AKT Signaling Pathway.

BACKGROUND/AIMS: Myocardial ischemia/reperfusion injury is a major cause of morbidity and mortality associated with coronary heart disease. Many studies have demonstrated that natural products are promising chemotherapeutic drugs counteracting the loss of cardiomyocytes. Thus, the purpose of the present study was to investigate the effects of geniposide, a traditional Chinese herb extract from Gardenia jasminoides J. Ellis, on cardiomyocyte apoptosis induced by hypoxia/reoxygenation (H/R) in H9c2 cells, and their underlying mechanisms. METHODS: Cell viability and apoptosis ratio were assessed using the cell counting kit-8 assay and Annexin V/propidium iodide (PI) staining. The concentrations of lactate dehydrogenase (LDH), intracellular total superoxide dismutase (T-SOD), and malondialdehyde (MDA) were detected by microplate reader. The production of reactive oxygen species/reactive nitrogen species (ROS/RNS), the level of mitochondrial calcium, and mitochondrial membrane potential depolarization were measured by confocal laser scanning microscopy. Mitochondrial morphology was visualized using transmission electron microscopy. The expressions of Bcl-2 mRNA and Caspase-3 mRNA were measured by reverse transcription-polymerase chain reaction (RT-PCR). The protein levels of cleaved caspase-3, Bcl-2, Bax, AKT, p-AKTserine473, cytochrome-c were detected by western bloting. RESULTS: Geniposide pretreatment increased cell viability, decreased LDH levels in the supernatant, and inhibited cardiomyocyte apoptosis caused by H/R. Furthermore, geniposide reversed mitochondrial dysfunction by decreasing oxidative stress products (ROS/RNS and MDA), increasing anti-oxidative enzyme (T-SOD) level, improving mitochondrial morphology, attenuating mitochondrial calcium overload and blunting depolarization of mitochondrial membrane. Moreover, geniposide pretreatment increased Bcl-2 level and decreased Bax level, thus enhancing the Bcl-2/Bax ratio. Consistent with the above result, Bcl-2 mRNA expression was upregulated and caspase-3 mRNA expression was downregulated by geniposide. In addition, geniposide decreased the protein expression of cleaved caspase-3 and cytochrome-c and increased the level p-AKTserine473. The protective effects of geniposide were partially reversed by glucagon-like pepitide-1 receptor antagonist exendin-(9-39) and the phosphatidylinositol 3 kinase (PI3K) inhibitor LY294002. CONCLUSIONS: Our results suggest that geniposide pretreatment inhibits H/R-induced myocardial apoptosis by reversing mitochondrial dysfunction, an effect in part due to activation of GLP-1R and PI3K/AKT signaling pathway.