Targeting deubiquitinase OTUB1 protects vascular smooth muscle cells in atherosclerosis by modulating PDGFRß.

Atherosclerosis is a chronic artery disease that causes various types of cardiovascular dysfunction. Vascular smooth muscle cells (VSMCs), the main components of atherosclerotic plaque, switch from contractile to synthetic phenotypes during atherogenesis. Ubiquitylation is crucial in regulating VSMC phenotypes in atherosclerosis, and it can be reversely regulated by deubiquitinases. However, the specific effects of deubiquitinases on atherosclerosis have not been thoroughly elucidated. In this study, RNAi screening in human aortic smooth muscle cells was performed to explore the effects of OTU family deubiquitinases, which revealed that silencing OTUB1 inhibited PDGF-BB-stimulated VSMC phenotype switch. Further in vivo studies using Apoe-/- mice revealed that knockdown of OTUB1 in VSMCs alleviated atherosclerosis plaque burden in the advanced stage and led to a stable plaque phenotype. Moreover, VSMC proliferation and migration upon PDGF-BB stimulation could be inhibited by silencing OTUB1 in vitro. Unbiased RNA-sequencing data indicated that knocking down OTUB1 influenced VSMC differentiation, adhesion, and proliferation. Mass spectrometry of ubiquitinated protein confirmed that proteins related to cell growth and migration were differentially ubiquitylated. Mechanistically, we found that OTUB1 recognized the K707 residue ubiquitylation of PDGFRß with its catalytic triad, thereby reducing the K48-linked ubiquitylation of PDGFRß. Inhibiting OTUB1 in VSMCs could promote PDGFRß degradation via the ubiquitin-proteasome pathway, so it was beneficial in preventing VSMCs' phenotype switch. These findings revealed that knocking down OTUB1 ameliorated VSMCs' phenotype switch and atherosclerosis progression, indicating that OTUB1 could be a valuable translational therapeutic target in the future.

Prospective Advances of Extracellular Vesicles Investigation in Cardiovascular and Metabolic Research.

Extracellular vesicles (EVs) play an important role in cardiovascular and metabolic diseases through intercellular communication. Although there has been extensive research on EVs, there are still some unsolved problems in the technologies of investigation of EVs. In this chapter, we reviewed the current knowledge of EVs functions in cardiovascular and metabolic pathophysiology and EVs as biomarkers and therapeutic agents in cardiovascular and metabolic diseases. We also addressed the challenges in isolation and identification of EVs as well as challenges in visualization and tracking of EVs. By addressing these challenges, we hope to have a more in-depth understanding of the biological functions of EVs.

Identification of circRNAs and circRNA-miRNA-mRNA regulatory network in radiation-induced heart disease.

OBJECTIVE: Radiation-induced heart disease (RIHD) is one of the most common and serious long-term adverse effect after thoracic radiotherapy. Our aim was to investigate the potential molecular mechanism underlying RIHD using RNA-sequencing (RNA-seq) and bioinformatics methods. MATERIALS AND METHODS: An RIHD rat model was established and transcription profiles were identified using RNA-seq. Differentially expressed circRNAs, miRNAs and mRNAs were identified. Enrichment of functions and signaling pathways analysis were performed based on GO and the KEGG database. Potential circRNA-miRNA-mRNA regulatory network underlying RIHD was established. qRT-PCR was used to validate the associated genes. RESULTS: In total, 21 circRNAs, 26 miRNAs, and 178 mRNA transcripts were differentially expressed in RIHD. GO and KEGG pathway analyses identified that differentially expressed mRNAs were most enriched in pathways referring to endothelial function and vascular pathological processes. Nine circRNAs, 10 miRNAs, and 6 mRNA transcripts were most likely involved in vascular function and a candidate competitive endogenous RNA (ceRNA) network of circRNA-miRNA-mRNA was established, which were further validated by qRT-PCR. CONCLUSIONS: Our study revealed that vascular pathology plays an important role in the early stage of RIHD. Furthermore, a circRNA-miRNA-mRNA ceRNA network was found that may be involved in the regulation of vascular function and RIHD.

Highly Purified Eicosapentaenoic Acid Alleviates the Inflammatory Response and Oxidative Stress in Macrophages during Atherosclerosis via the miR-1a-3p/sFRP1/Wnt/PCP-JNK Pathway.

Highly purified eicosapentaenoic acid (EPA) has shown great effects in the prevention of atherosclerosis. In a murine model, it significantly reduced plaque accumulation, lowered plasma lipid levels, and decreased inflammation levels, which was also observed in vitro. Using microRNA sequencing, we identified differentially expressed microRNAs, among which miR-1a-3p was selected for further validation. Overexpression of miR-1a-3p in RAW264.7 cells worsened lipid accumulation, increased oxidative stress, and exacerbated inflammatory responses whereas its downregulation produced the opposite results. Potential targets of miR-1a-3p were analyzed by prediction tools. Then, secreted frizzled-related protein 1 (sFRP1), an antagonist of the Wnt pathway, was confirmed as the target gene of miR-1a-3p by a dual-luciferase reporter assay. Further research showed that in macrophages, EPA influenced the activation of the Wnt/planar cell polarity-c-Jun N-terminal kinase (Wnt/PCP-JNK) axis, which is consistent with the phenomenon that miR-1a-3p has an impact on this same axis. Collectively, our findings suggest that EPA mitigates inflammatory responses and oxidative responses both in vivo and in vitro by targeting the miR-1a-3p/sFRP1/Wnt/PCP-JNK axis in macrophages, which may explain the cardioprotective role of EPA and promote the application of EPA in clinical practice.

Association of Controlling Nutritional Status Score With 2-Year Clinical Outcomes in Patients With ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention.

BACKGROUND: This study evaluated whether the Controlling Nutritional Status (CONUT) score could predict clinical outcomes in ST elevation myocardial infarction (STEMI) patients. METHODS: We performed a retrospective cohort study of STEMI patients after primary percutaneous coronary intervention (pPCI). The endpoint was major adverse cardiac event (MACE). Information was obtained from medical records and via telephone calls. Patients were divided into three groups: normal (CONUT score 0-1; n=278), mild-moderate (score 2-4; n=418), and severe (score ≥5; n=55) groups. RESULTS: During the 24.6±12 months follow-up, MACEs were observed in 65 (8.7%) patients. The incidence of MACEs was 6.1%, 5.5%, and 45.5% in the normal, mild-moderate, and severe group, respectively (p<0.001). Kaplan-Meier curves revealed that patients with a CONUT score ≥5 had the significantly highest rate of MACE, myocardial re-infarction, and vessel revascularisation. In three Cox proportional hazard models, the CONUT scores were unexceptionally associated with MACE, even after adjusting all other variables (hazard ratio, 12.09; 95% confidence interval [CI], 5.09-28.7; p<0.001). The C-statistic of the CONUT score for the prediction of MACE was 0.692 (95% CI, 0.613-0.771; p<0.001), which is close to that of Global Registry of Acute Coronary Events. CONCLUSIONS: The nutritional status evaluated by the CONUT score can independently predict clinical outcomes in STEMI patients, which suggests that active nutritional management is meaningful for these patients after PCI.

Trimedazidine alleviates pulmonary artery banding-induced acute right heart dysfunction and activates PRAS40 in rats.

The molecular mechanism underlying acute right heart failure (RHF) is poorly understood. We used pulmonary artery banding (PAB) to induce acute RHF characterized by a rapid rise of right ventricular pressure, and then a decrease in right ventricular pressure along with a decrease in blood pressure right after banding. We found higher brain natriuretic peptide (BNP) and beta-myosin heavy chain (ßMHC) levels and lower alpha-myosin heavy chain (αMHC) levels in RHF rats than sham-operated rats. Hemodynamic indexes in rats with acute RHF were slightly improved by trimedazidine TMZ, a key inhibitor of fatty acid (FA) oxidation. TMZ also reversed downregulation of peroxisome proliferator-activated receptor gamma coactivator 1-beta (PGC-1ß) and peroxisome proliferator-activated receptor alpha (PPARα) by PAB and up-regulates peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), peroxisome proliferator-activated receptor delta (PPARδ) and pyruvate dehydrogenase kinase isoform 4 (PDK4). In addition, TMZ reversed upregulation of phosphorylated Akt by PAB and increased phosphorylated proline-rich Akt-substrate 40 (PRAS40). Autophagy and apoptosis were not modified by PAB or TMZ. An acute RHF model was established in rats through 70% constriction of the pulmonary artery. TMZ treatment alleviated PAB-induced acute RHF by activating PRAS40 and upregulatingPGC-1α, PGC-1ß, PPARα, PPARδ, and PDK4.

miR-31a-5p promotes postnatal cardiomyocyte proliferation by targeting RhoBTB1.

A limited number of microRNAs (miRNAs, miRs) have been reported to control postnatal cardiomyocyte proliferation, but their strong regulatory effects suggest a possible therapeutic approach to stimulate regenerative capacity in the diseased myocardium. This study aimed to investigate the miRNAs responsible for postnatal cardiomyocyte proliferation and their downstream targets. Here, we compared miRNA profiles in cardiomyocytes between postnatal day 0 (P0) and day 10 (P10) using miRNA arrays, and found that 21 miRNAs were upregulated at P10, whereas 11 were downregulated. Among them, miR-31a-5p was identified as being able to promote cardiomyocyte proliferation as determined by proliferating cell nuclear antigen (PCNA) expression, double immunofluorescent labeling for α-actinin and 5-ethynyl-2-deoxyuridine (EdU) or Ki-67, and cell number counting, whereas miR-31a-5p inhibition could reduce their levels. RhoBTB1 was identified as a target gene of miR-31a-5p, mediating the regulatory effect of miR-31a-5p in cardiomyocyte proliferation. Importantly, neonatal rats injected with a miR-31a-5p antagomir at day 0 for three consecutive days exhibited reduced expression of markers of cardiomyocyte proliferation including PCNA expression and double immunofluorescent labeling for α-actinin and EdU, Ki-67 or phospho-histone-H3. In conclusion, miR-31a-5p controls postnatal cardiomyocyte proliferation by targeting RhoBTB1, and increasing miR-31a-5p level might be a novel therapeutic strategy for enhancing cardiac reparative processes.

MicroRNA-222 Promotes the Proliferation of Pulmonary Arterial Smooth Muscle Cells by Targeting P27 and TIMP3.

BACKGROUND/AIMS: Aberrant vascular smooth muscle cell (VSMC) proliferation plays an important role in the development of pulmonary artery hypertension (PAH). Dysregulated microRNAs (miRNAs, miRs) have been implicated in the progression of PAH. miR-222 has a pro-proliferation effect on VSMCs while it has an anti-proliferation effect on vascular endothelial cells (ECs). As the biological function of a single miRNA could be cell-type specific, the role of miR-222 in pulmonary artery smooth muscle cell (PASMC) proliferation is not clear and deserves to be explored. METHODS: PASMCs were transfected with miR-222 mimic or inhibitor and PASMC proliferation was determined by Western blot for PCNA, Ki-67 and EdU staining, and cell number counting. The target genes of miR-222 including P27 and TIMP3 were determined by luciferase assay and Western blot. In addition, the functional rescue experiments were performed based on miR-222 inhibitor and siRNAs to target genes. RESULTS: miR-222 mimic promoted PASMC proliferation while miR-222 inhibitor decreased that. TIMP3 was identified to be a direct target gene of miR-222 based on luciferase assay. Meanwhile, P27 and TIMP3 were up-regulated by miR-222 inhibitor and down-regulated by miR-222 mimic. Moreover, P27 siRNA and TIMP3 siRNA could both attenuate the anti-proliferation effect of miR-222 inhibitor in PASMCs, supporting that P27 and TIMP3 are at least partially responsible for the regulatory effect of miR-222 in PASMCs. CONCLUSION: miR-222 promotes PASMC proliferation at least partially through targeting P27 and TIMP3.

Serum Irisin Predicts Mortality Risk in Acute Heart Failure Patients.

BACKGROUND/AIMS: Irisin is a peptide hormone cleaved from a plasma membrane protein fibronectin type III domain containing protein 5 (FNDC5). Emerging studies have indicated association between serum irisin and many major chronic diseases including cardiovascular diseases. However, the role of serum irisin as a predictor for mortality risk in acute heart failure (AHF) patients is not clear. METHODS: AHF patients were enrolled and serum was collected at the admission and all patients were followed up for 1 year. Enzyme-linked immunosorbent assay was used to measure serum irisin levels. To explore predictors for AHF mortality, the univariate and multivariate logistic regression analysis, and receiver-operator characteristic (ROC) curve analysis were used. To determine the role of serum irisin levels in predicting survival, Kaplan-Meier survival analysis was used. RESULTS: In this study, 161 AHF patients were enrolled and serum irisin level was found to be significantly higher in patients deceased in 1-year follow-up. The univariate logistic regression analysis identified 18 variables associated with all-cause mortality in AHF patients, while the multivariate logistic regression analysis identified 2 variables namely blood urea nitrogen and serum irisin. ROC curve analysis indicated that blood urea nitrogen and the most commonly used biomarker, NT-pro-BNP, displayed poor prognostic value for AHF (AUCs ≤ 0.700) compared to serum irisin (AUC = 0.753). Kaplan-Meier survival analysis demonstrated that AHF patients with higher serum irisin had significantly higher mortality (P<0.001). CONCLUSION: Collectively, our study identified serum irisin as a predictive biomarker for 1-year all-cause mortality in AHF patients though large multicenter studies are highly needed.

Qiliqiangxin Attenuates Adverse Cardiac Remodeling after Myocardial Infarction in Ovariectomized Mice via Activation of PPARγ.

BACKGROUND/AIMS: This study was designed to investigate the therapeutic effect of traditional Chinese medication Qiliqiangxin (QLQX) on adverse cardiac remodeling after myocardial infarction (MI) in bilateral ovariectomized (OVX) female mice. METHODS: Eight-week old female C57BL/6 mice were operated to ligate the left anterior descending coronary artery seven days after bilateral ovariectomy and were orally administered either QLQX or vehicle. 21 days after ligation, echocardiography was performed to evaluate the heart function of all mice. Masson's Trichrome staining was applied to evaluate myocardial fibrosis. Collagen deposition was determined by the mRNA level of Collagen I, Collagen III and α-SMA using real-time quantitative polymerase chain reaction (qPCR). Myocardial apoptosis was examined by the protein level of Bax, Bcl2 and the Bcl2/Bax ratio using western blotting. RESULTS: These mice displayed a significant reduction in heart function, increased myocardial fibrosis and apoptosis, and decreased expression of peroxisome proliferator activated receptor γ (PPARγ) in the heart tissue, which could be reversed by QLQX treatment. Inhibition of PPAR reduced QLQX-mediated cardio-protective effects, while PPARγ activation did not further enhance the beneficial effect of QLQX. Furthermore, QLQX upregulated 9 genes (Cd36, Fatp, Pdk4, Acadm, Acadl, Acadvl, Cpt1a, Cpt1b and Cpt2) facilitating energy metabolism in the MI hearts of the OVX mice and 5 (Acadm, Acadl, Cpt1a, Cpt1b, Cpt2) of the 9 genes were the downstream targets of PPARγ. CONCLUSION: The present study indicates that QLQX has a treatment effect on pathological remodeling post MI in bilateral OVX female mice via activation of PPARγ, suggesting that QLQX may be a promising prescription for the treatment of postmenopausal women suffering from MI.

Long Non-Coding RNAs in Cardiac Remodeling.

Cardiac remodeling occurs after stress to the heart, manifested as pathological processes, including hypertrophy and apoptosis of cardiomyocytes, dysfunction of vascular endothelial cells and vascular smooth muscle cells as well as differentiation and proliferation of fibroblasts, ultimately resulting in progression of cardiovascular diseases. Emerging evidence has revealed that long non-coding RNAs (lncRNAs) acted as powerful and dynamic modifiers of cardiac remodeling. LncRNAs including Chaer, Chast, Mhrt, CHRF, ROR, H19, and MIAT have been implicated in cardiac hypertrophy while NRF, H19, APF, CARL, UCA, Mhrt and several other lncRNAs (n379599, n379519, n384640, n380433 and n410105) in cardiomyocyte loss and extracellular matrix remodeling. In addition, MALAT1 and TGFB2-OT1 have been reported to contribute to vascular endothelial cells dysfunction while lincRNA-p21 and lnc-Ang362 to vascular smooth muscle cells proliferation. Thus, manipulation of lncRNA expression levels through either the inhibition of disease-up-regulated lncRNAs or increasing disease-down-regulated lncRNAs represents novel therapeutic strategies for cardiac remodeling.

Qiliqiangxin attenuates isoproterenol-induced cardiac remodeling in mice.

BACKGROUND: To further explore the role of PPARγ in QL treatment, ISO-induced mice model and following methods were established. METHODS: Cardiac remodeling on mice model was induced by isoproterenol (ISO) infusion or saline infusion as control for two weeks then divided into 4 groups, after that divided in 5 different treatment methods to investigate the role of PPARγ in QL therapy. Echocardiography and Masson's trichrome staining were respectively used to determine cardiac function and fibrosis. Immunoblotting was applied to evaluate the expression levels of proliferator-activated receptor-γ (PPARγ), Bax, Bcl, phospho-Akt (Ser473), Akt, phospho-P38 and P38, phosphor-ERK and ERK. RESULTS: QL treatment improved left ventricular function, decreased apoptosis, and prevented myocardial fibrosis at the same time. Meanwhile, the PPARγ level was elevated with QL treatment in ISO-injected mice hearts. Inhibition of PPARγ activity blocked the protective effects of QL, while the activator of PPARγ did not provide additional benefit. Specifically, the results indicated a decline in PPARγ in ISO-infused mice and QL decreased the toxicity of ISO by improving the level of PPARγ. CONCLUSIONS: Our study demonstrated that QL treatment provided cardioprotection against ISO-induced cardiac remodeling by improving PPARγ level, which could be as the potential therapeutic target in reversing cardiac remodeling and heart failure.

Qiliqiangxin Attenuates Phenylephrine-Induced Cardiac Hypertrophy through Downregulation of MiR-199a-5p.

BACKGROUND/AIMS: Qiliqiangxin (QL), a traditional Chinese medicine, has long been used to treat chronic heart failure. Previous studies demonstrated that QL could prevent cardiac remodeling and hypertrophy in response to hypertensive or ischemic stress. However, little is known about whether QL could modulate cardiac hypertrophy in vitro, and (if so) whether it is through modulation of specific hypertrophy-related microRNA. METHODS: The primary neonatal rat ventricular cardiomyocytes were isolated, cultured, and treated with phenylephrine (PE, 50 µmol/L, 48 h) to induce hypertrophy in vitro, in the presence or absence of pretreatment with QL (0.5 µg/ml, 48 h). The cell surface area was determined by immunofluorescent staining for α-actinin. The mRNA levels of hypertrophic markers including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and ß-myosin heavy chain (MYH7) were assayed by qRT-PCRs. The protein synthesis of cardiomyocytes was determined by the protein/DNA ratio. The miR-199a-5p expression level was quantified in PE-treated cardiomyocytes and heart samples from acute myocardial infarction (AMI) mouse model. MiR-199a-5p overexpression was used to determine its role in the anti-hypertrophic effect of QL on cardiomyocytes. RESULTS: PE induced obvious enlargement of cell surface in cardiomyocytes, paralleling with increased ANP, BNP, and MYH7 mRNA levels and elevated protein/DNA ratio. All these changes were reversed by the treatment with QL. Meanwhile, miR-199a-5p was increased in AMI mouse heart tissues. Of note, the increase of miR-199a-5p in PE-treated cardiomyocytes was reversed by the treatment with QL. Moreover, overexpression of miR-199a-5p abolished the anti-hypertrophic effect of QL on cardiomyocytes. CONCLUSION: QL prevents PE-induced cardiac hypertrophy. MiR-199a-5p is increased in cardiac hypertrophy, while reduced by treatment with QL. miR-199a-5p suppression is essential for the anti-hypertrophic effect of QL on cardiomyocytes.

miR-21-3p controls sepsis-associated cardiac dysfunction via regulating SORBS2.

Cardiac dysfunction with sepsis is a major cause of death in intensive care units. Several lines of evidence have revealed the potential of microRNAs (miRNAs, miRs) as biomarkers for detecting sepsis, though direct evidence of their functional roles in septic cardiac dysfunction is still lacking. In this study, C57BL/6 mice were exposed to lipopolysaccharide (LPS) to induce sepsis-associated cardiac dysfunction, as evidenced by reduced fractional shortening (FS) and ejection fraction (EF) and detrimental changes in cardiac contractility, inflammation, and energy metabolism. Microarray analysis and qRT-PCRs revealed that miR-21-3p was significantly induced in heart samples challenged with LPS. Impressively, pharmacological inhibition of miR-21-3p using antagomiR was able to preserve FS and EF and prevent mitochondria ultrastructural damage and autophagy in LPS-treated mice, while forced expression of miR-21-3p using agomiR aggravated that. Besides that, miR-21-3p antagomiR improved the survival of mice treated with LPS. Meanwhile, our data showed that SH3 domain-containing protein 2 (SORBS2) was inversely correlated with miR-21-3p expression level in mice hearts, and was repressed in hearts challenged with LPS, suggesting SORBS2 as a target gene of miR-21-3p. Additionally, plasma miR-21-3p was markedly elevated in septic patients with cardiac dysfunction as compared to septic patients without cardiac dysfunction. The ROC curve showed that plasma miR-21-3p could be a specific predictor of septic patients developing cardiac dysfunction with an area under the curve of 0.939. Collectively, the present study provides strong evidence that miR-21-3p controls sepsis-associated cardiac dysfunction via regulating SORBS2. Inhibition of miR-21-3p might be a protective strategy to treat sepsis-induced cardiac dysfunction.

The Metabolic Effects of Traditional Chinese Medication Qiliqiangxin on H9C2 Cardiomyocytes.

BACKGROUND/AIMS: A traditional Chinese medicine, Qiliqiangxin (QLQX) has been identified to perform protective effects on myocardium energy metabolism in mice with acute myocardial infarction, though the effects of QLQX on myocardial mitochondrial biogenesis under physiological condition is still largely elusive. METHODS: H9C2 cells were treated with different concentrations of QLQX (0.25, 0.5, and 1.0 µg/mL) from 6 to 48 hours. Oxidative metabolism and glycolysis were measured by oxygen consumption and extracellular acidification with XF96 analyzer (SeaHorse). Mitochondrial content and ultrastructure were assessed by Mitotracker staining, confocal microscopy, flow cytometry, and transmission electron microscopy. Mitochondrial biogenesis-related genes were measured by qRT-PCR and Western blot. RESULTS: H9C2 cells treated with QLQX exhibited increased glycolysis at earlier time points (6, 12, and 24 hours), while QLQX could enhance oxidative metabolism and mitochondrial uncoupling in H9C2 cells with longer duration of treatment (48 hours). QLQX also increased mitochondrial content and mitochondrial biogenesis-related gene expression levels, including 16sRNA, SSBP1, TWINKLE, TOP1MT and PLOG, with an activation of peroxisome proliferator-activated receptor coactivator 1 alpha (PGC-1α) and its downstream effectors. Silencing PGC-1α could abolish the increased mitochondrial content in H9C2 cells treated with QLQX. CONCLUSION: Our study is the first to document enhanced metabolism in cardiomyocytes treated with QLQX, which is linked to increased mitochondrial content and mitochondrial biogenesis via activation of PGC-1α.

Exercise Training Protects Against Acute Myocardial Infarction via Improving Myocardial Energy Metabolism and Mitochondrial Biogenesis.

BACKGROUND/AIMS: Acute myocardial infarction (AMI) represents a major cause of morbidity and mortality worldwide. Exercise has been proved to reduce myocardial ischemia-reperfusion (I/R) injury However it remains unclear whether, and (if so) how, exercise could protect against AMI. METHODS: Mice were trained using a 3-week swimming protocol, and then subjected to left coronary artery (LCA) ligation, and finally sacrificed 24 h after AMI. Myocardial infarct size was examined with triphenyltetrazolium chloride staining. Cardiac apoptosis was determined by TUNEL staining. Mitochondria density was checked by Mito-Tracker immunofluorescent staining. Quantitative reverse transcription polymerase chain reactions and Western blotting were used to determine genes related to apoptosis, autophagy and myocardial energy metabolism. RESULTS: Exercise training reduces myocardial infarct size and abolishes AMI-induced autophagy and apoptosis. AMI leads to a shift from fatty acid to glucose metabolism in the myocardium with a downregulation of PPAR-α and PPAR-γ. Also, AMI induces an adaptive increase of mitochondrial DNA replication and transcription in the acute phase of MI, accompanied by an activation of PGC-1α signaling. Exercise abolishes the derangement of myocardial glucose and lipid metabolism and further enhances the adaptive increase of mitochondrial biogenesis. CONCLUSION: Exercise training protects against AMI-induced acute cardiac injury through improving myocardial energy metabolism and enhancing the early adaptive change of mitochondrial biogenesis.

Qiliqiangxin Protects Against Cardiac Ischemia-Reperfusion Injury via Activation of the mTOR Pathway.

BACKGROUND/AIMS: Qiliqiangxin (QL) has been used for the treatment of chronic heart failure in China. Accumulating evidence suggests QL's cardio-protective effects on continuous myocardial ischemia. However, it is unclear whether QL has beneficial effects on cardiac ischemia-reperfusion (I/R) injury. METHODS: A mouse model of cardiac I/R was established by ligation of the left anterior descending coronary artery for 45 minutes followed by reperfusion. The mice were treated with QL for three days before surgery and continually after I/R. Triphenyltetrazolium chloride staining, echocardiography and Masson's trichrome staining were used to determine infarct size, cardiac function, and fibrosis, respectively. Expression levels of phospho-mTOR (Ser2448), mTOR, phospho-4EBP (Ser65), 4EBP, phospho-Akt (Ser473) and Akt were detected by Western blotting. RESULTS: At 1 day after I/R, QL treatment significantly reduced the infarct size of mice exposed to I/R. At 7 days after I/R, mortality was reduced in QL treated animals in comparison with the control group. In addition, QL treated mice showed increased left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) at 1 and 7 days after I/R. In agreement, Masson's trichrome staining demonstrated that interstitial fibrosis was less pronounced in QL treated mice compared with controls, suggesting that adverse left ventricular remodeling is attenuated in QL treated mice. Moreover, western blotting analysis demonstrated that QL activated the mTOR pathway, while mTOR inhibition via Rapamycin abolished the protective effects of QL against I/R injury. CONCLUSION: This study suggests that QL attenuates the progression of cardiac remodeling after I/R likely via mTOR activation. This represents a new application for QL in the prevention of I/R injury.

Common Variants for Heart Failure.

Heart failure (HF) is a common disease with high morbidity and mortality; however, none of the drugs available are now entirely optimal for the treatment of HF. In addition to various clinical diseases and environment influences, genetic factors also contribute to the development and progression of HF. Identifying the common variants for HF by genome-wide association studies will facilitate the understanding of pathophysiological mechanisms underlying HF. This review summarizes the recently identified common variants for HF risk and outcome and discusses their implications for the clinic therapy.

Tendency for age-specific mortality with hypertension in the European Union from 1980 to 2011.

Tendency for mortality in hypertension has not been well-characterized in European Union (EU). Mortality data from 1980 to 2011 in EU were used to calculate age-standardized mortality rate (ASMR, per 100,000), annual percentage change (APC) and average annual percentage change (AAPC). The Joinpoint Regression Program was used to compare the changes in tendency. Mortality rates in the most recent year studied vary between different countries, with the highest rates observed in Slovakia men and Estonia women. A downward trend in ASMR was demonstrated over all age groups. Robust decreases in ASMR were observed for both men (1991-1994, APC = -13.54) and women (1996-1999, APC = -14.80) aged 55-65 years. The tendency of systolic blood pressure (SBP) from 1980 to 2009 was consistent with ASMR, and the largest decrease was observed among Belgium men and France women. In conclusion, SBP associated ASMR decreased significantly on an annual basis from 1980 to 2009 while a slight increase was observed after 2009. Discrepancies in ASMR from one country to another in EU are significant during last three decades. With a better understanding of the tendency of the prevalence of hypertension and its mortality, efforts will be made to improve awareness and help strict control of hypertension.