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Compared with stem cells, exosomes as a kind of nanoscale carriers intrinsically loaded with diverse bioactive molecules, which had the advantages of high safety, small size, and ethical considerations in the treatment of myocardial infarction, but there are still problems such as impaired stability and rapid dissipation. Here, we introduce a bioengineered injectable hyaluronic acid hydrogel designed to optimize local delivery efficiency of trophoblast stem cells derived-exosomes. Its hyaluronan components adeptly emulates the composition and modulus of pericardial fluid, meanwhile preserving the bioactivity of nanoscale exosomes. Additionally, a meticulously designed hyperbranched polymeric cross-linker facilitates a gentle cross-linking process among hyaluronic acid molecules, with disulfide bonds in its molecular framework enhancing biodegradability and conferring a unique controlled release capability. This innovative hydrogel offers the added advantage of minimal invasiveness during administration into the pericardial space, greatly extending the retention of exosomes within the myocardial region. In vivo, this hydrogel has consistently demonstrated its efficacy in promoting cardiac recovery, inducing anti-fibrotic, anti-inflammatory, angiogenic, and anti-remodeling effects, ultimately leading to a substantial improvement in cardiac function. Furthermore, the implementation of single-cell RNA sequencing has elucidated that the pivotal mechanism underlying enhanced cardiac function primarily results from the promoted clearance of apoptotic cells by myocardial fibroblasts., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

Background: Platelet activation and thrombus formation play critical roles in the pathogenesis of myocardial infarction (MI). In addition to their role in energy production, platelet mitochondria also regulate cellular functions related to apoptosis, oxidative stress, and inflammation. Epigenetic modifications of platelet mitochondrial DNA (mtDNA) may influence platelet function and are believed to be an important factor in MI. Therefore, the aim of this study was to investigate the differences in platelet mtDNA methylation levels between MI patients and controls., Methods: The present study utilized propensity score matching to generate 45 multivariate matched apparently healthy controls for 45 patients with newly-onset acute MI. Platelet mtDNA methylation levels were assessed through bisulfite-PCR pyrosequencing and compared between the two groups, with further adjustments made in the sensitivity analysis., Results: Among the measured mitochondrial genes (MT-COX1, MT-COX2, MT-COX3, MT-ND5, MT-ATP6 and tRNA&#95;Leu), patients with MI exhibited statistically significant differences in mtDNA methylation levels as compared to matched controls. Specifically, higher levels of mtDNA methylation were observed in MT-COX1, MT-COX3, and tRNA&#95;Leu, while a lower level was observed in MT-ATP6 (all p < 0.0001). These results remained robust in the sensitivity analysis., Conclusion: Our study demonstrated significant variations in platelet mtDNA methylation levels between patients with MI and controls. Platelet mtDNA methylation may serve as a novel biomarker for MI. This observation also provided some insights into the etiology of MI., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Mesenchymal stem cell (MSC)-based cardiac patches are envisioned to be a promising treatment option for patients with myocardial infarction. However, their therapeutic efficacy and duration are hampered due to their limited retention on the epicardium. We engineered a scaffold-free MSC sheet with an inherent ability to migrate into the infarcted myocardium, a strategy enabled by actively establishing a sustained intracellular hypoxic environment through the endocytosis of our FDA-approved ferumoxytol. This iron oxide nanoparticle stabilized hypoxia-induced factor-1α, triggering upregulation of the CXC chemokine receptor and subsequent MSC chemotaxis. Thus, MSCs integrated into 2/3 depth of the left ventricular anterior wall in a rat model of acute myocardial infarction and persisted for at least 28 days. This led to spatiotemporal delivery of paracrine factors by MSCs, enhancing cardiac regeneration and function. Ferumoxytol also facilitated the noninvasive MRI tracking of implanted MSCs. Our approach introduces a strategy for mobilizing MSC migration, holding promise for rapid clinical translation in myocardial infarction treatment.

Background: Patients with a history of hypertension have elevated inflammation and a worse prognosis after acute myocardial infarction (AMI). Regulatory T cells (Tregs) are reported to lose their immunosuppressive capacity under pathological conditions. However, whether hypertension leads to Treg dysfunction, thus accelerating myocardial ischemia-reperfusion injury, is still unknown., Methods: Studies were performed in hypertensive rats and mice with myocardial ischemia-reperfusion injury. The frequencies and phenotypes of Tregs were analyzed by flow cytometry and immunohistochemistry. Reconstruction Treg experiments were performed to evaluate the effect of Tregs on ischemia-reperfusion injury. Patients with AMI were enrolled to assess circulating Tregs, inflammatory cytokines, and cardiac function., Results: In this study, we found that hypertension leads to proinflammatory Th1 (T helper 1 cell)-like Treg subsets with compromised suppressive capacity. Reconstruction Treg experiments identified that dysfunctional Tregs induced by hypertension play a pathogenic role in the progression of myocardial ischemia-reperfusion injury. In particular, we identified HDAC6 (histone deacetylase 6) as a central regulator in the perturbed Tregs. Clinical studies revealed that the hypertension-induced reduction in circulating Tregs strongly correlated with the higher occurrence rate of microvascular obstruction in AMI patients with hypertension., Conclusions: Our study provided promising clues to explain the poor prognosis of hypertensive AMI patients due to alterations in Tregs. Targeting disturbed Tregs may be a new strategy to treat AMI patients with hypertension., Competing Interests: Disclosures None.

Purpose: Myocardial ischemia-reperfusion injury after myocardial infarction has always been a difficult problem in clinical practice. Endothelial cells and their secreted extracellular vesicles are closely related to inflammation, thrombosis formation, and other processes after injury. Meanwhile, low-molecular-weight gelators have shown great potential for nasal administration. This study aims to explore the therapeutic effects and significance of endothelial cell-derived extracellular vesicles combined with a hydrogel for nasal administration on myocardial ischemia-reperfusion injury., Methods: We chose a gel system composed of a derivative of glutamine amide and benzaldehyde as the extracellular vesicle delivery vehicle. This hydrogel was combined with extracellular vesicles extracted from mouse aortic endothelial cells and administered multiple times intranasally in a mouse model of ischemia-reperfusion injury to the heart. The delivery efficiency of the extracellular vesicle-hydrogel combination was evaluated by flow cytometry and immunofluorescence. Echocardiography, TTC Evan's Blue and Masson's staining were used to assess mouse cardiac function, infarct area, and cardiac fibrosis level. Flow cytometry, ELISA, and immunofluorescence staining were used to investigate changes in mouse inflammatory cells, cytokines, and vascular neogenesis., Results: The vesicles combined with the hydrogel have good absorption in the nasal cavity. The hydrogel combined with vesicles reduces the levels of pro-inflammatory Ly6C (high) monocytes/macrophages and neutrophils. It can also reduce the formation of microcirculation thrombi in the infarcted area, improve endothelial barrier function, and increase microvascular density in the injured area. As a result, the heart function of mice is improved and the infarct area is reduced., Conclusion: We first demonstrated that the combination of extracellular vesicles and hydrogel has a better absorption efficiency in the nasal cavity, which can improve myocardial ischemia-reperfusion injury by inhibiting inflammatory reactions and protecting endothelial function. Nasal administration of vesicles combined with hydrogel is a potential therapeutic direction., Competing Interests: The authors report no conflicts of interest in this work., (© 2023 Wang et al.)

Background: Sacubitril/Valsartan, a dual inhibitor of the neprilysin and angiotensin receptor, exerts cardioprotective effects in heart failure. Little is known on the impact of Sacubitril/Valsartan in hypertensive patients early post myocardial infarction., Methods: Spontaneously hypertensive rats (SHR) were pretreated by daily angiotensin receptor blocker (ARB; 30 mg/kg intraperitoneally), Sacubitril/Valsartan (ARNI; 60 mg/kg intraperitoneally) or the same dosage of physiological saline for 1 week. Then each group underwent myocardial infarction induction and received the same treatment for another week. The blood pressure and cardiac function were evaluated prior to sacrifice. We performed histological and molecular evaluation of fibrosis in vivo and in vitro., Results: The blood pressure was comparable between three groups both 1 week prior to and post myocardial infarction. ARNI and ARB restore the decreased ejection fraction (57.3 ± 7.6 vs. 42.9 ± 5.2%, P < 0.05; 54.3 ± 6.9 vs. 42.9 ± 5.2%, P < 0.01, respectively) and fractional shortening (31.6 ± 5.4 vs. 22.1 ± 3.1%, P < 0.05; 29.4 ± 4.5 vs. 22.1 ± 3.1%, P < 0.05, respectively) post myocardial infarction. The infarct size and collagen deposition were also significantly mitigated in ARNI and ARB groups. In addition, ARNI and ARB treatment reduced the expression of cardiac remodeling-related factors, such as Bnp, α-SMA, Vimentin, and Col1a1 (all P < 0.05 vs. MI group). Finally, ARNI and ARB decreased the expression of α-SMA in cardiac fibroblasts treated with Ang II., Conclusion: In conclusion, pretreatment with ARNI maintained cardiac function and reduced myocardial fibrosis in myocardial infarction, probably prior to any anti-hypertensive effect., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Dyslipidemia is an important risk factor for myocardial infarction (MI). This study aimed to examine the health-related quality of life (HRQoL) and its predictors of patients with MI combined with dyslipidemia in China. Methods: Information on patients' sociological characteristics, lifestyle, clinical characteristics, and quality of life were collected by electronic medical records and questionnaires. Tobit regression model was used to investigate the predictors of quality of life. Results: There were 756 patients responded. The average EQ-5D score of all the patients was 0.95 (SD: 0.11). For all patients, factors such as age, high-fat and high-cholesterol diet, sports, family history of dyslipidemia, history of peripheral artery disease significantly affected HRQoL. Conclusions: Post-discharge care of the elderly group should be paid more attention to and suggestions on the healthy lifestyle (fat control) of the patients should be encouraged to improve the quality of life of these population., Competing Interests: Amgen Biotech Consultation (Shanghai) Co., Ltd partly sponsored this study. However, The funder had no role in study design, data collection and analysis, and preparation of the manuscript. This study does not involve any specific products. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Chen, Zhang, Su, Chen, Xu, Tao, Wang, Li and Ma.)

Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) with anti-apoptotic and anti-inflammatory properties have been intensively studied. However, rapid clearance by the mononuclear phagocyte system remains a huge barrier for the delivery of extracellular vesicle contents into target organs and restricts its wider application, particularly in the heart. CD47 is a transmembrane protein that enables cancer cells to evade clearance by macrophages through CD47 - signal regulatory proteinα binding, which initiates a "don't eat me" signal. This study aimed to explore the biodistribution and delivery efficiency of EVs carrying the membrane protein CD47 and specific anti-apoptotic miRNAs. EVs were isolated from MSCs overexpressing CD47 (CD47-EVs) and identified. Fluorescence-labeled EVs were injected through the tail vein and tracked using fluorescence imaging. In silico analysis was performed to determine miRNA profiles in MSCs and in a heart-derived H9c2 cardiomyoblast cell line under hypoxia vs. normoxia conditions. Electro CD47-EV was constructed by encapsulating purified CD47-EV with miR-21a via electroporation. The effect of miR21-EVs on the pro-apoptotic gene encoding phosphatase and tensin homolog (PTEN) was evaluated by dual-luciferase assay, qPCR, and western blotting. Exogenous miR21 distribution, PTEN protein level, blood vessel density, anti-apoptotic effect by TdT-mediated dUTP nick-end labeling staining, and macrophage and leukocyte infiltration in the myocardium were assessed by immunofluorescence staining. Cardiac functional recovery during the early stage and recovery period was evaluated using echocardiography. The results showed that CD47-EVs were still detectable in the plasma 120 min after the tail vein injection, compared to the detection time of less than 30 min observed with the unmodified EVs. More strikingly, CD47-EVs preferentially accumulated in the heart in the ischemia-reperfusion (I/R) + CD47-EV group [heart total fluorescence radiance ( × 10 5 Photons/sec/cm 2 /sr) 51.62 ± 11.30 v.s. 10.08 ± 3.15 in the I/R + unmodified EVs group] 8 h post-injection. Exogenous miR-21 is efficiently internalized into cardiomyocytes, inhibits apoptosis, alleviates inflammation, and improves cardiac function. In conclusion, electro CD47-EVs efficiently improve biodistribution in the heart, shedding new light on the application of a two-step EV delivery method (CD47 genetic modification followed by therapeutic content electrotransfection) as a potential therapeutic tool for myocardial I/R injury that may benefit patients in the future., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objectives: Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been confirmed to reduce the rate of rehospitalization for heart failure and cardiovascular death in diabetic patients. The aim of our study was to investigate the cardioprotective role of SGLT2 inhibitors in early myocardial infarction (MI) of non-diabetic mice., Methods: C57BL/6 mice underwent left artery coronary artery descending (LAD) ligation to induce MI. Following the surgery, animals were randomized to receive saline or empagliflozin. Empagliflozin (EMPA) was administrated at 10 mg/kg per day by oral gavage for 2 weeks. Echocardiography, histological staining and qualitative RT-PCR were performed to assess the cardiac remodeling post MI. In vitro experiments were performed to evaluate the effect of empagliflozin on apoptosis, oxidative stress and mitochondrial membrane potential of cardiomyocyte subjected to hypoxic treatment., Results: Compared with MI group, the empagliflozin treatment group showed improved cardiac function, reduced infarct size and interstitial fibrosis. Empagliflozin also inhibited cardiomyocyte apoptosis by alleviating oxidative stress and restoring mitochondrial membrane potential. Immunoblotting analysis revealed activated AMP-activated protein kinase (AMPK) signaling may mediated the cardioprotective role of empagliflozin., Conclusions: In summary, empagliflozin could inhibit cardiomyocyte apoptosis and improve cardiac remodeling early MI, which provided insights into the benefic effect of empagliflozin on MI patients without diabetes., (Copyright © 2021. Published by Elsevier B.V.)

Background: Dyslipidemia is a common comorbidity and an important risk factor for myocardial infarction (MI). This study aimed to examine the economic burden of MI combined with dyslipidemia in China. Methods: Patients who were hospitalized due to MI combined with dyslipidemia in 2016 were enrolled. Costs were measured based on electronic medical records and questionnaires. The annual costs were analyzed by conducting descriptive statistics, univariable, and multivariable analyses. Results: Data of 900 patients were analyzed, and 144 patients were dead during the follow-up. The majority of patients were aged 51-70 years ( n = 563, 62.55%) and males ( n = 706, 78.44%). For all-cause costs, the median annual direct medical costs, direct non-medical costs, indirect costs, and total costs were RMB 13,168 (5,212-29,369), RMB 600 (0-1,750), RMB 676 (0-1,787), RMB 15,361 (6,440-33,943), respectively; while for cardiovascular-related costs, the corresponding costs were RMB 12,233 (3,795-23,746), RMB 515 (0-1,680), RMB 587 (0-1,655), and RMB 14,223 (4,914-28,975), respectively. Lifestyle and complications significantly affected both all-cause costs and cardiovascular-related costs. Conclusions: Increasing attention should be paid to encourage healthy lifestyle, and evidence-based medicine should focus on optimal precautions and treatments for complications, to reduce the economic burden among MI patients with a comorbid dyslipidemia., Competing Interests: Amgen Biotech Consultation (Shanghai) Co., Ltd partly sponsored this study. However, this study is an economic burden investigation, which does not involve any specific products. Therefore, the authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Chen, Zhang, Zhang, Su, Chen, Xu, Tao, Wang, Ma and Li.)

The cardiac repair after myocardial infarction (MI) involves two phases, namely, inflammatory response and proliferative response. The former is an inflammatory reaction, evoked by different kinds of pro-inflammatory leukocytes and molecules stimulated by myocardial necrosis, while the latter is a repair process, predominated by a magnitude of anti-inflammatory cells and cytokines, as well as fibroblasts. Cardiac remodeling post-MI is dependent on the balance of individualized intensity of the post-MI inflammation and subsequent cardiac fibrosis. During the past 30 years, enormous studies have focused on investigating immune cells and mediators involved in cardiac inflammation and fibrosis, which are two interacting processes of post-MI cardiac repair. These results contribute to revealing the mechanism of adverse cardiac remodeling after MI and alleviating the impairment of cardiac function. In this study, we will broadly discuss the role of immune cell subpopulation and the involved cytokines and chemokines during cardiac repair post-MI, particular in cardiac inflammation and fibrosis., (© 2020 Wiley Periodicals, Inc.)

Background: The angiogenesis post myocardial infarction (MI) is compromised in diabetes. MiR-144-3p is reported to be highly expressed in circulating exosomes of diabetic patients, implying its role in diabetic complications. However, whether circulating exosomes and enriched miR-144-3p are involved in the impaired neovascularization in diabetes and the underlying mechanism is unclear., Results: DMexo and miR-144-3p mimic-treated MSCs had elevated miR-144-3p levels and decreased MMP9, Ets1 and PLG expression. The percentage of EPCs were relatively lower in DMexo-treated or agomir-treated MI mice compared with MI mice. Finally, the luciferase assay confirmed the direct binding between miR-144-3p and Ets1., Conclusion: Exosomal miR-144-3p could impair the mobilization ability of EPCs, which was associated with impaired ischemia-induced neovascularization., Methods: Circulating exosomes were isolated from Streptozotocin (STZ)-induced mice. In vitro , mesenchymal stem cells (MSCs) were incubated with exosomes from diabetic mice (DMexo), and miR-144-3p mimic or inhibitor. miR-144-3p, and MMP9 pathway were measured using qPCR and immunoblotting. In vivo , MI mice induced by left anterior descending ligation were treated with DMexo, as well as miR-144-3p agomir. Flow cytometry was used to profile endothelial progenitor cells (EPCs) in peripheral blood and bone marrow post 24 hours respectively.

Mounting evidence has indicated that long non-coding RNA maternally expressed gene 3 (lncRNA MEG3) regulates cell apoptosis, and is involved in a variety of diseases. However, its exact role in myocardial infarction (MI) has not been fully elucidated. In the present study, we firstly observed that the expression levels of the lncRNA MEG3 in infarct hearts and hypoxic neonatal mice ventricular myocytes (NMVMs) were up-regulated by quantitative real-time PCR (qRT-PCR). Then, we knocked down lncRNA MEG3 by lentiviral delivery in the myocardial border region following multipoint injection. Following 28 days of MI, the lncRNA MEG3 knockdown mice indicated better cardiac function, and less cardiac remodelling by ultrasonic cardiogram and histological analysis. In addition, we indicated that lncRNA MEG3 knockdown reduced myocyte apoptosis and reactive oxygen species production in MI mice model and hypoxic NMVMs. Furthermore, we revealed that knockdown of lncRNA MEG3 protected against endoplasmic reticulum stress (ERS)-mediated myocardial apoptosis including the induction of PERK-eIF2α and caspase 12 pathways. At last, we provided evidence that p53 was identified as a protein target of lncRNA MEG3 to regulate NF-κB- and ERS-associated apoptosis. Taken collectively, our findings demonstrated that lncRNA MEG3 knockdown exerted cardioprotection by reducing ERS-mediated apoptosis through targeting p53 post-MI., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine.)

Aims: Mesenchymal stromal cells (MSCs) gradually become attractive candidates for cardiac inflammation modulation, yet understanding of the mechanism remains elusive. Strikingly, recent studies indicated that exosomes secreted by MSCs might be a novel mechanism for the beneficial effect of MSCs transplantation after myocardial infarction. We therefore explored the role of MSC-derived exosomes (MSC-Exo) in the immunomodulation of macrophages after myocardial ischaemia/reperfusion (I/R) and its implications in cardiac injury repair., Methods and Results: Exosomes were isolated from the supernatant of MSCs using gradient centrifugation method. Administration of MSC-Exo to mice through intramyocardial injection after myocardial I/R reduced infarct size and alleviated inflammation level in heart and serum. Systemic depletion of macrophages with clodronate liposomes abolished the curative effects of MSC-Exo. MSC-Exo modified the polarization of M1 macrophages to M2 macrophages both in vivo and in vitro. miRNA sequencing of MSC-Exo and bioinformatics analysis implicated miR-182 as a potent candidate mediator of macrophage polarization and toll-like receptor 4 (TLR4) as a downstream target. Diminishing miR-182 in MSC-Exo partially attenuated its modulation of macrophage polarization. Likewise, knock down of TLR4 also conferred cardioprotective efficacy and reduced inflammation level in a mouse model of myocardial I/R., Conclusion: Our data indicate that MSC-Exo attenuates myocardial I/R injury in mice via shuttling miR-182 that modifies the polarization status of macrophages. This study sheds new light on the application of MSC-Exo as a potential therapeutic tool for myocardial I/R injury., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Objective: This study aims to compare the clinical effects of selective interventional therapy (PCI) under the guidance of fractional flow reserve (FFR) and coronary arteriography., Methods: Patients with sub-acute ST-segment elevation myocardial infarction (sub-acute STEMI), who were under selective PCI treatment between April 2012 and June 2014, were included into this study. These patients were divided into two groups, based on FFR measurements: FFR-PCI group and radiography-PCI group. Then, differences in clinical symptoms, coronary angiography, intervention, and endpoint events were compared between these two groups., Results: A total of 592 patients with sub-acute STEMI were included in this study (207 patients in the FFR-PCI group and 385 patients in the radiography-PCI group). No statistical differences were observed in baseline clinical data and coronary angiography results between these two groups. Mean stent number was greater in the radiography-PCI group (1.22 ± 0.32) than in the FFR-PCI group (1.10 ± 0.29), and the difference was statistically significant (P = 0.019). During the follow-up period, 78 adverse events occurred (21 adverse events in the FFR-PCI group and 57 adverse events in the radiography-PCI group); and no statistical significance was observed between these two groups (log-rank P = 0.112)., Conclusion: Selective PCI treatment in patients with sub-acute STEMI under FFR acquired similar effects, compared to PCI treatment under the guidance of radiography, which can reduce the mean stent number.

Clinical evidence has indicated an increased myocardial infarction (MI) morbidity and mortality after exposure to air pollution (particulate matter<2.5 μm, PM2.5). However, the mechanisms by which PM2.5 aggravates MI remain unknown. Present study was to explore the adverse effect of PM2.5 on myocardium after MI and the potential mechanisms. Male mice with MI surgery were treated with PM2.5 by intranasal instillation. Neonatal mice ventricular myocytes (NMVMs) subjected to hypoxia were also incubated with PM2.5 to determine the role of PM2.5 in vitro. Exposure to PM2.5 significantly impaired the cardiac function and increased the infarct size in MI mice. TUNEL assay, flow cytometry and western blotting of Caspase 3, Bax and BCl-2 indicated that PM2.5 exposure could cause cellular apoptosis in vivo and in vitro. Besides, PM2.5 activated NFκB pathway and increased gene expression of IL-1β and IL-6 in NMVMs with hypoxia, which could be effectively reversed by SN-50-induced blockade of NFκB translocation to the nucleus. In summary, air pollution induces myocardium apoptosis and then impairs cardiac function and aggravates MI via NFκB activation., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Various stem cells have been explored for the purpose of cardiac repair. However, any individual stem cell population has not been considered as the ideal source. Recently, trophoblast stem cells (TSCs), a newly described stem cell type, have demonstrated extensive plasticity. The present study evaluated the therapeutic effect of TSCs transplantation for heart regeneration in a mouse model of myocardial infarction (MI) and made a direct comparison with the most commonly used mesenchymal stem cells (MSCs). Transplantation of TSCs and MSCs led to a remarkably improved cardiac function in contrast with the PBS control, but only the TSCs exhibited the potential of differentiation into cardiomyocytes in vivo. In addition, a significantly high proliferation level of both transplanted stem cells and resident cardiomyocytes was observed in the TSCs group. These findings primary revealed the therapeutic potential of TSCs in transplantation therapy for MI.

The effect of mesenchymal stem cell (MSCs)-based therapy on treating acute myocardial infarction (MI) is limited due to poor engraftment and limited regenerative potential. Here we engineered MSCs with integrin-linked kinase (ILK), a pleiotropic protein critically regulating cell survival, proliferation, differentiation, and angiogenesis. We firstly combined ferumoxytol with poly-L-lysine (PLL), and found this combination promisingly enabled MRI visualization of MSCs in vitro and in vivo with good safety. We provided visually direct evidence that intracoronary ILK-MSCs had substantially enhanced homing capacity to infarct myocardium in porcine following cardiac catheterization induced MI. Intracoronary transplantation of allogeneic ILK-MSCs, but not vector-MSCs, significantly enhanced global left ventricular ejection fraction (LVEF) by 7.8% compared with baseline, by 10.3% compared with vehicles, and inhibited myocardial remodeling compared with vehicles at 15-day follow-up. Compared with vector-MSCs, ILK-MSCs significantly improved regional LV contractile function, reduced scar size, fibrosis, cell apoptosis, and increased regional myocardial perfusion and cell proliferation. This preclinical study indicates that ILK-engineered MSCs might promote the clinical translation of MSC-based therapy in post-MI patients, and provides evidence that ferumoxytol labeling of cells combined with PLL is feasible in in vivo cell tracking.

Background: The prognostic significance of right bundle branch block (RBBB) is inconsistent across studies. We aimed to assess the association between RBBB (in general population and patients with heart disease) and risk of all-cause mortality, cardiac death, acute myocardial infarction (MI), and heart failure (HF)., Hypothesis: RBBB may be associated with increased risk of death., Methods: PubMed, EMBASE, and the Cochrane Library up to February 2015 were searched for prospective cohort studies that reported RBBB at baseline and all-cause mortality, cardiac death, MI, and HF at follow-up. A meta-analysis of published data was undertaken primarily by means of fixed-effects models., Results: Nineteen cohort studies including 201 437 participants were included with a mean follow-up period ranging from 1 to 246 months. For general population with RBBB, the pooled adjusted hazard ratio (HR) for all-cause mortality was 1.17 (95% confidence interval [CI]: 1.03-1.33) compared with no BBB. General population with RBBB had an increased risk of cardiac death (HR: 1.43, 95% CI: 1.17-1.74). For patients with RBBB and acute MI, the pooled risk ratio was 2.31 (95% CI: 2.13-2.49) for in-hospital mortality, 2.85 (95% CI: 2.46-3.30) for 30-day mortality, and 1.96 (95% CI: 1.59-2.42) for longer-term mortality. For acute HF patients, the pooled risk ratio of all-cause mortality was 1.11 (95% CI: 1.06-1.16), and for chronic HF patients it was 1.75 (95% CI: 1.38-2.22)., Conclusions: Right bundle branch block is associated with an increased risk of mortality in general population and patients with heart disease., (© 2015 Wiley Periodicals, Inc.)

In the present study, we investigated whether mesenchymal stem cells (MSCs) overexpressing integrin-linked kinase (ILK) might regulate ventricular remodeling and cardiac function in a porcine myocardial infarction model. ILK-modified MSCs (ILK-MSCs) (n = 8), MSCs (n = 8) or placebo (n = 8) were injected into peri-infarct myocardium 7 days after ligation of the left anterior descending coronary artery. ILK expression was confirmed by immunofluorescence, real-time PCR, Western blot analysis, and flow cytometry. In vitro assays indicated increased proliferation and reduced apoptosis of MSCs due to overexpression of ILK. Echocardiographic, single-photon emission computed tomography and positron emission tomography analyses demonstrated preserved cardiac function and myocardial perfusion. Reduced fibrosis, increased cardiomyocyte proliferation, and enhanced angiogenesis were observed in the ILK-MSC group. Reduced apoptosis, as demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling analysis, was also noted. In conclusion, ILK promotes MSC proliferation and suppresses apoptosis. ILK-MSC transplantation improves ventricular remodeling and cardiac function in pigs after MI. It is associated with increased angiogenesis, reduced apoptosis, and increased cardiomyocyte proliferation. This may represent a new approach to the treatment of post-infarct remodeling and subsequent heart failure.

MicroRNAs are involved in the regulation of various cellular processes, including cell apoptosis and autophagy. Expression of microRNA-99a (miR-99a) is reduced in apoptotic neonatal mice ventricular myocytes (NMVMs) subjected to hypoxia. We hypothesize that miR-99a might restore cardiac function after myocardial infarction (MI) by up-regulation of myocyte autophagy and apoptosis. We observed down-regulated miR-99a expression in NMVMs exposed to hypoxia using TaqMan quantitative reverse transcriptase-polymerase chain reaction analysis (RT-PCR). We also observed that miR-99a overexpression decreased hypoxia-mediated apoptosis in cultured NMVMs. To investigate whether overexpression of miR-99a in vivo could improve cardiac function in ischaemic heart, adult C57/BL6 mice undergoing MI were randomized into two groups and were intra-myocardially injected with lenti-99a-green fluorescent protein (GFP) or lenti-GFP (control). Four weeks after MI, lenti-99a-GFP group showed significant improvement in both left ventricular (LV) function and survival ratio, as compared to the lenti-GFP group. Histological analysis, western blotting analysis and electron microscopy revealed decreased cellular apoptosis and increased autophagy in cardiomyocytes of lenti-99a-GFP group. Furthermore, western blotting analysis showed inhibited mammalian target of rapamycin (mTOR) expression in the border zones of hearts in miR-99a-treated group. Our results demonstrate that miR-99a overexpression improves both cardiac function and survival ratio in a murine model of MI by preventing cell apoptosis and increasing autophagy via an mTOR/P70/S6K signalling pathway. These findings suggest that miR-99a plays a cardioprotective role in post-infarction LV remodelling and increased expression of miR-99a may have a therapeutic potential in ischaemic heart disease., (© 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Background: This study was to investigate the effect of integrin-linked kinase (ILK) on the transplantation efficiency of stem cell antigen-1-positive cardiac progenitor cells (Sca-1 CPCs) in a mouse myocardial infarction (MI) model., Methods: Sca-1 CPCs were isolated from C57/BL6 mice heart tissues and genetically modified with adenovirus vector containing green fluorescent protein (GFP)/ILK or GFP. Cell viability, migration, DNA synthesis, proliferation, and apoptosis were assessed in vitro. Immediately after MI, treated animals received 5×10 GFP-CPC or ILK-CPC transplantation into the peri-infarct myocardium. Cardiac function, exercise ability, cardiac morphology, angiogenesis, cardiomyocyte apoptosis, as well as ILK-related protein expression were measured. Acute and long-term cell survival after cell transplantation was assessed., Results: Overexpression of ILK increased the viability, migration, DNA synthesis, proliferation, and survival of Sca-1 CPCs in vitro. Protein expression of phosphorylated Akt and cyclin D1 were up-regulated. In our in vivo experiment, more transplanted cells were found in the peri-infarct myocardium in ILK-CPC group 3 days after cell transplantation, but there was no difference between the two groups 4 weeks later. ILK-CPC group showed reduced infarct size 7 days after cell transplantation. Long-term observation showed improved cardiac function indicated by higher percent fractional shortening and lower left ventricular end systolic diameter/left ventricular end diastolic diameter, better exercise ability, increased angiogenesis, decreased fibrosis and apoptosis, as well as up-regulation of ILK, Cdc42, and Aurora B protein expression in ILK-CPC group 4 weeks after cell transplantation., Conclusions: ILK-overexpressed Sca-1 CPCs showed improved therapeutic efficacy in MI.

Objective: We aimed to assess the chemotactic response of endothelial progenitor cells to angiotensin-converting enzyme inhibitors in T2DM patients after acute myocardial infarction, as well as the associated prognosis., Methods: Sixty-eight T2DM patients with acute myocardial infarction were randomized to either receive or not receive daily oral perindopril 4 mg, and 36 non-diabetic patients with acute myocardial infarction were enrolled as controls. The numbers of circulating CD45-/low+CD34+CD133+KDR+ endothelial progenitor cells, as well as the stromal cell-derived factor-α and high-sensitivity C reactive protein levels, were measured before acute percutaneous coronary intervention and on days 1, 3, 5, 7, 14, and 28 after percutaneous coronary intervention. Patients were followed up for 6 months. Chinese Clinical Trial Registry: ChiCTR-TRC-12002599., Results: T2DM patients had lower circulating endothelial progenitor cell counts, decreased plasma vascular endothelial growth factor and α levels, and higher plasma high-sensitivity C reactive protein levels compared with non-diabetic controls. After receiving perindopril, the number of circulating endothelial progenitor cells increased from day 3 to 7, as did the plasma levels of vascular endothelial growth factor and stromal cell-derived factor-α, compared with the levels in T2DM controls. Plasma high-sensitivity C reactive protein levels in the treated group decreased to the same levels as those in non-diabetic controls. Furthermore, compared with T2DM controls, the perindopril-treated T2DM patients had lower cardiovascular mortality and occurrence of heart failure symptoms (p<0.05) and better left ventricle function (p<0.01)., Conclusions: The use of angiotensin-converting enzyme inhibitors represents a novel approach for improving cardiovascular repair after acute myocardial infarction in T2DM patients.

Syndecan-4 (synd4) is a heparan sulfate proteoglycan, involved in repair following tissue damage, through modulating neovascularization and inflammation. In acute myocardial infarction its myocardial expression is up-regulated in a time-dependent manner, and in synd4-deficient mice severe cardiac dysfunction and abnormal remodeling are observed following induction of myocardial infarction. Here we explored the therapeutic potential of sustained synd4 over-expression in the context of myocardial infarction. Adenovirus containing the synd4 gene (Ad-synd4), or corresponding control adenovirus (Ad-null), was administered intramyocardially in rats immediately after induction of myocardial infarction. Cardiac function was ascertained by echocardiography, hemodynamic assessment and brain natriuretic peptide level 28 days post-intervention. Hearts were excised for molecular and histological analyses at predetermined time points. We observed reduced mortality and improved cardiac function post-myocardial infarction in the Ad-synd4 as compared to the Ad-null group, with associated attenuation of cardiac remodeling, less myocyte loss and reduced fibrosis. Additionally, the Ad-synd4 group exhibited endothelial cell activation and increased angiogenesis and arteriogenesis in the myocardium. The Ad-synd4 group also showed evidence of reduced myocardial inflammation as compared with the Ad-null group, with reduced inflammatory cell (CD45+) and myofibroblast (α-SMA+) infiltration as well as suppressed collagen III deposition and iNOS expression. Our results suggest that sustained synd4 over-expression in the myocardium is of therapeutic benefit following experimental myocardial infarction, through inducing neovascularization, suppressing tissue inflammation and fibrosis, with resultant improvements in cardiac function and remodeling., (Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.)

Background: Melusin, a muscle-specific integrin-linked protein, has been reported to be a biomechanical sensor and to protect the heart from pressure overload. In the present study, we investigated the possible role that melusin plays during cardiac remodeling after myocardial infarction (MI)., Methods: We constructed a heart failure model of rats induced by left anterior descending coronary artery ligation. At different time points (1, 2, 3, 4, 6, and 8 weeks) following the operation, cardiac function was monitored by echocardiography and hemodynamic assessment; cardiac morphology was measured using hematoxylin-eosin-stained sections. Melusin expression, as well as p-Akt, Akt, and one of the Rho small GTPase family members, CDC42, was determined dynamically by Western blotting analysis during the postinfarction cardiac remodeling., Results: Progressive increase in left ventricular (LV) end-systolic dimension and LV end-diastolic dimension and decrease in percent LV fractional shortening (%FS) and LVdp/dt(max) demonstrated gradually deteriorated cardiac function in rats following MI operation. Morphological analysis revealed cardiac remodeling in MI animals, including increased LV diameter and decreased border zone thickness. We also showed a dynamic change in melusin during heart failure progression; it had an initial decline which was evident at 3 weeks and increased subsequently, reaching peak levels at 6 weeks. This dynamic change in melusin was significantly correlated with %FS and LVdp/dt(max.) p-Akt/Akt and CDC42 protein expression was correlated with melusin content., Conclusions: The altered melusin pathways and CDC42 parallel the cardiac function progression during cardiac remodeling post-MI. The dynamic change of them during this procedure may represent an important molecular mechanism underlying postinfarction cardiac remodeling and provide potential therapeutic targets., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Although the clinical outcome of acute myocardial infarction (AMI) in patients with type 2 diabetes mellitus (T2DM) is well established to be worse than for non-diabetic patients, the reasons for this remain unclear. We hypothesized that this may be related to impairment of bone marrow-derived endothelial progenitor cells (EPCs) mobilization., Methodology/principal Findings: We observed short term bone marrow EPCs mobilization and long term clinical outcomes in 62 AMI patients with or without T2DM and investigated EPCs levels as well as bone marrow pathway changes in a rat model of diabetes after AMI. Patients with T2DM exhibited a delay (peak time diabetics vs. non-diabetics: day 7 vs. day 5) and a decrease in EPCs mobilization (diabetics vs. non-diabetics: 285±56/10⁶ mononuclear cells (MNCs) vs. 431±88/10⁶ MNCs, p<0.05) within one month after AMI. Plasma levels of VEGF and SDF-1α as well as of hsCRP were higher in T2DM patients. Over a mean of 2.26 years follow-up, T2DM patients exhibited a pronounced decrease in LVEF as well as an increase in clinical events. Glucose (HR 2.01, 95% CI 1.42-2.85, p = 0.008), first day EPC (HR 0.974, 95% CI 0.952-0.997, p = 0.02) and seven day EPCs (HR 0.966, 95% CI 0.945-0.988, p = 0.003) were independent prognostic variables for cardiovascular mortality. In a diabetic rat model of AMI, decreased circulating EPCs was accompanied by lower expression of phospho-Akt, phospho-eNOS, HIF, MMP-9 and MMP-9 activity in the bone marrow as well as impaired cardiac function, angiogenesis and increased left ventricle remodeling., Conclusions/significance: Bone marrow EPCs mobilization is delayed and reduced in diabetes, with impaired HIF/p-Akt/p-eNOS/MMP-9 signaling. This is likely to contribute to the deterioration in cardiac function and worsened clinical outcome seen in patients with T2DM.

Background: Integrin linked kinase (ILK), as an important component of mechanical stretch sensor, can initiate cellular signaling response in the heart when cardiac preload increases. Previous work demonstrated increased ILK expression could induce angiogenesis to improved heart function after MI. However the patholo-physiological role of ILK in cardiac remodeling after MI is not clear., Method and Results: Hearts were induced to cardiac remodeling by infarction and studied in Sprague-Dawley rats. Until 4 weeks after infarction, ILK expression was increased in non-ischemic tissue in parallel with myocytes hypertrophy and compensatory cardiac function. 8 weeks later, when decompensation of heart function occurred, ILK level returned to baseline. Followed ILK alternation, vascular endothelial growth factor (VEGF) expression and phosphorylation of endothelial nitric oxide synthase (eNOS) was significantly decreased 8 weeks after MI. Histology study also showed significantly microvessel decreased and myocytes loss 8 weeks paralleled with ILK down-regulation. While ILK expression was maintained by gene delivery, tissue angiogenesis and cardiac function was preserved during cardiac remodeling., Conclusion: Temporally up-regulation of ILK level in non-ischemic myocytes by increased external load is associated with beneficial angiogenesis to maintain infarction-induced cardiac hypertrophy. When ILK expression returns to normal, this cardiac adaptive response for infarction is weaken. Understanding the ILK related mechanism of cardiac maladaptation leads to a new strategy for treatment of heart failure after infarction.

Background: Left ventricular (LV) remodeling is associated with the development of heart failure after myocardial infarction. Here we investigated whether integrin-linked kinase (ILK) may regulate LV remodeling and function after myocardial infarction., Methods and Results: Adenoviral vector expressing ILK (n=25) or empty adeno-null (n=25) was injected into rat peri-infarct myocardium after left anterior descending coronary artery ligation. ILK expression was confirmed by Western blotting and immunofluorescence. Echocardiographic and hemodynamic analyses demonstrated relatively preserved cardiac function in adeno-ILK animals. ILK treatment was associated with reduced infarct scar size, increased scar thinning ratio, and preserved LV diameter, wall thickness, cardiomyocyte size, and myofilament density. Enhanced angiogenesis and reduced fibrosis were observed in the adeno-ILK group, along with reduced apoptosis as demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling analysis. Moreover, increased cardiomyocyte proliferation was found in adeno-ILK animals, as measured by proliferating cell nuclear antigen, Ki-67, and phosphohistone-H3 staining. At long-term follow-up, most indices of cardiac function and hemodynamics showed no difference between adeno-ILK and control animals by 9 weeks, although LV end-systolic diameter and infarct scar size were reduced in the adeno-ILK group at this time point. Additionally, ILK overexpression was found to exert a rescue effect on remodeling when administered in a delayed fashion 1 week after coronary artery ligation., Conclusions: ILK gene therapy improves cardiac remodeling and function in rats after myocardial infarction and is associated with increased angiogenesis, reduced apoptosis, and increased cardiomyocyte proliferation. This may represent a new approach to the treatment of postinfarct remodeling and subsequent heart failure.

Background: Vascular endothelial growth factor (VEGF) is an important active protein for the induction of angiogenesis and improvement in cardiac function after myocardial ischemia; however, the lack of a delivery system targeted to the injured myocardium reduces the local therapeutic efficacy of VEGF and increases its possible adverse effects., Methods and Results: We produced a fusion protein (CBD-VEGF) consisting of VEGF and a collagen-binding domain (CBD). The fusion protein specifically bound to type I collagen in vitro. In addition, CBD-VEGF promoted human umbilical vein endothelial cell proliferation after binding to collagen, which indicates that it retained both growth factor activity and collagen-binding ability. When implanted subcutaneously in rats, collagen membranes loaded with CBD-VEGF were significantly vascularized. After it was injected into rats with acute myocardial infarction, CBD-VEGF was largely retained in the cardiac extracellular matrix, in which collagen I was rich. Four weeks after VEGF or CBD-VEGF was injected into the infarct border zone, cardiac function detected by echocardiography and hemodynamics was preserved in the CBD-VEGF group. Administration of CBD-VEGF also induced reduction of scar size, whereas native VEGF did not have these effects. In addition, a significant increase in the number of capillary vessels in infarcted hearts was found in the CBD-VEGF group., Conclusions: The injection of CBD-VEGF improved cardiac function in rats with induced acute myocardial infarction. This could potentially provide a new treatment option for myocardial infarction.

Erythropoietin (EPO), known for its role in stimulating erythropoiesis, has recently been shown to have a cardio-protective effect in animal models of myocardial ischemia-reperfusion (I-R) injury. The mechanism of the cardio-protective effect of EPO is unclear. Part of the mechanism for EPO-induced cardio-protection may involve inhibition of myocardial apoptosis and preservation of ATP levels in the ischemic myocardium. We studied the expression of heat shock protein 70 (Hsp70) and its possible links to the cardio-protective effect of EPO. A rat model of myocardial I-R injury was established by ligating the left descending coronary artery for 30 min and then reperfusing for 2 hr. Recombinant human EPO (rhEPO) was injected ip 24 hr before the ligation. The myocardial infarct size and the area at risk of ischemia were measured by staining with triphenyltetrazolium chloride (TTC) and Evans blue dye. Expression of Hsp70 in the left ventricle was analyzed by ELISA and that of nuclear factor-kappaB (NF-kappaB) was analyzed by electrophoretic mobility shift assay (EMSA). The results showed that a single ip injection of 3,000 units/kg of rhEPO at 24 hr pre-ligation enhanced the expression of Hsp70 and diminished the expression of NF-kappaB in rat myocardium, and that the myocardial infarct induced by I-R injury was remarkably reduced in size, compared to control rats that received an ip saline injection at 24 hr pre-ligation.

Background. The relationship between fasting blood glucose (FBG) and microvascular obstruction (MVO) after primary percutaneous coronary intervention (PCI) remains unclear in nondiabetic patients with ST-segment elevation myocardial infarction (STEMI). This study aimed to determine the predictive value of FBG in MVO in nondiabetic STEMI patients. Methods. A total of 108 nondiabetic STEMI patients undergoing primary PCI were enrolled in this study. The patients were classified into either the MVO group or non-MVO group based on cardiac magnetic resonance imaging (CMR). Results. FBG in the MVO group was higher than in the non-MVO group. Univariate analysis showed that FBG, peak high-sensitive troponin T (TnT), pre-PCI thrombolysis in myocardial infarction (pre-PCI TIMI) flow, left ventricular ejection fraction (LVEF), infarction size, left ventricular end-diastolic diameter (LVEDd), left ventricular end-diastolic volume (LVEDV), and global longitudinal strain (GLS) were likely predictive factors of MVO. After adjustment for other parameters, FBG, peak TnT, LVEF, and LVEDV remained independent predictors for MVO. Conclusion. FBG was independently associated with MVO in nondiabetic STEMI patients. [ABSTRACT FROM AUTHOR]

Myocardial ischemia–reperfusion (I/R) injury leads to intensive sympathetic nervous system (SNS) activation and inflammatory reactions. Whether renal sympathetic denervation (RDN) could be a new therapeutic strategy to modulate I/R inflammation and reduce infarct size after myocardial I/R injury needs to be explored. First, we investigated the correlation between plasma norepinephrine concentrations and circulating myeloid cell numbers in patients with acute myocardial infarction. And then, C57BL/6 mice underwent a "two-hit" operation, with 10% phenol applied to bilateral renal nerves to abrogate sympathoexcitation, and a 45-min ligation of the left coronary artery to induce myocardial I/R injury. The effects of RDN on the mobilization of immune cells in mice following myocardial I/R injury were explored. We observed a strong association between SNS overactivation and myeloid cell excessive accumulation in patients. In animal experiments, there was a significant reduction in infarct size per area at risk in the denervated-I/R group when compared to that of the innervated-I/R group (39.2% versus 49.8%; p < 0.005), and RDN also improved the left ventricular ejection fraction by 20% after 1 week. Furthermore, the denervated-I/R group showed a decrease in the number of neutrophils and macrophages in the blood and the myocardium as reflected by immunohistochemical staining and flow cytometry analysis (p < 0.05); the decrease was associated with a significant reduction in the circulating production of IL-1, IL-6 and TNF-α (p < 0.05). In summary, our study reveals a novel link between the SNS activity and inflammatory response undergoing myocardium I/R injury and identifies RDN as a potential therapeutic strategy against myocardium I/R injury via preserving the spleen immune cells mobilization. [ABSTRACT FROM AUTHOR]

Background: Many recent trials have investigated the long-term efficacy and safety of endarterectomy versus stenting in treating patients with carotid artery stenosis. We aimed to determine the long-term comparative efficacy and safety of both procedures by pooling this evidence in a meta-analysis. Methods: We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for studies published until May 6, 2016. Randomized controlled trials, which reported outcomes of interest with a median follow-up of at least 4-year, were included. Results: Eight trials involving 7005 patients and 41824 patient-years of follow-up were included. In terms of the periprocedural outcomes, stenting was associated with a lower risk of myocardial infarction (OR: 0.51; 95% CI: 0.33 to 0.80; P = 0.003) but a higher risk of death or stroke (the composite endpoint, OR: 1.76; 95% CI: 1.38 to 2.25; P < 0.0001), a result that was primarily driven by minor stroke (OR: 2.19; 95% CI: 1.59 to 3.01; P < 0.0001), less so by periprocedural death (OR: 1.68; 95% CI: 0.82 to 3.44; P = 0.16) and major stroke (OR: 1.41; 95% CI: 0.95 to 2.09; P = 0.09). In terms of the long-term outcomes, stenting was associated with a higher risk of stroke (OR 1.45; 95% CI: 1.22 to 1.73; P < 0.0001) and the composite outcome of death or stroke (OR 1.25; 95% CI: 1.05 to 1.48; P = 0.01). No difference was found in long-term all-cause mortality between stenting and endarterectomy (OR: 1.09; 95% CI: 0.95 to 1.26; P = 0.21) and restenosis (OR: 1.48 (95% CI: 0.93 to 2.35; P = 0.10). No evidence of significant heterogeneity was found in any of the analyses. Conclusions: Carotid endarterectomy was found to be superior to stenting for short- and long-term outcomes, although endarterectomy was associated with a higher risk of periprocedural myocardial infarction. Carotid endarterectomy should be offered as the first choice for carotid stenosis at present, however, more evidence is needed because rapid progress in concurrent devices and medical treatments is being made. [ABSTRACT FROM AUTHOR]

Objective: A number of studies have evaluated the efficacy and safety of fondaparinux versus low-molecular-weight heparin (LMWH) in patients with acute coronary syndrome (ACS), but the findings were not consistent across these studies. Methods: Electronic databases and article references were searched for studies that assessed fondaparinux versus LMWH in ACS patients. Results: Six studies met the inclusion criteria. There was a lower risk of major adverse cardiac events (MACE) with fondaparinux-based regimens both in randomized controlled trials (RCT; risk ratio, RR: 0.91, p = 0.04) and observational studies (RR: 0.85, p < 0.0001). Mortality decreased in fondaparinux-treated patients in RCT (RR: 0.84, p = 0.02), but not in observational studies (RR: 1.44, p = 0.64). For the analysis of myocardial infarction (MI), recurrent ischemia and stroke, none of the studies showed significant results. In addition, fondaparinux lowered the risk of major bleeding in RCT (RR: 0.62, p < 0.0001) and observational studies (RR: 0.65, p < 0.0001). The net clinical outcome also favored fondaparinux over LMWH in RCT (RR: 0.82, p < 0.0001) and observational studies (RR: 0.84, p < 0.0001). Conclusions: Among ACS patients, a fondaparinux-based regimen presented advantages regarding MACE and major bleeding, and a net clinical benefit compared with LMWH, although the benefit is minimal regarding MACE. For death, MI, recurrent ischemia and stroke, fondaparinux has not shown significant benefits. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Myocardial fibrosis is an essential hallmark of diabetic cardiomyopathy (DCM) contributing to cardiac dysfunctions. Resveratrol, an antioxidant, exerts its anti-fibrotic effect via inhibition of oxidative stress, while the underlying molecular mechanism remains largely elusive. Periostin, a fibrogenesis matricellular protein, has been shown to be associated with oxidative stress. In the present study, we investigated the role of periostin in anti-fibrotic effect of resveratrol in streptozocin (STZ)-induced diabetic heart and the underlying mechanisms.Methods: Diabetic mice were induced by STZ injection. After treatment with resveratrol (5 or 25 mg/kg/day i.g) or Saline containing 0.5% carboxymethyl cellulose (CMC) for 2 months, the hearts were detected for oxidative stress and cardiac fibrosis using western blot, Masson's trichrome staining and Dihydroethidium (DHE) staining. In in vitro experiments, proliferation and differentiation of fibroblasts under different conditions were investigated through western blot, 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay and immunofluorescence staining.Results: Administration of resveratrol significantly mitigated oxidative level, interstitial fibrosis and expressions of related proteins in STZ-induced diabetic hearts. In in vitro experiments, resveratrol exhibited anti-proliferative effect on primary mouse cardiac fibroblasts via inhibiting reactive oxygen species (ROS)/extracellular regulated kinase (ERK) pathway and ameliorated myofibroblast differentiation via suppressing ROS/ERK/ transforming growth factor β (TGF-β)/periostin pathway.Conclusion: Increased ROS production, activation of ERK/TGF-β/periostin pathway and myocardial fibrosis are important events in DCM. Alleviated ROS genesis by resveratrol prevents myocardial fibrosis by regulating periostin related signaling pathway. Thus, inhibition of ROS/periostin may represent a novel approach for resveratrol to reverse fibrosis in DCM. [ABSTRACT FROM AUTHOR]

Background: The relative short-, long- and overall-term efficacy and safety of sirolimus-eluting stents (SES, Cypher) compared with paclitaxel-eluting stents (PES, Taxus) in large head-to-head comparisons still remain to be defined. Methods: We searched Pubmed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) for articles comparing outcomes of interest between SES and PES without language restriction. Short- (≤1 year), long- (>1 year), and overall-term (the longest follow-up of each study) outcomes were evaluated. The primary endpoint was target lesion revascularization (TLR). Other outcomes of interest were target vessel revascularization (TVR), myocardial infarction, all-cause death, cardiac death, stent thrombosis, major adverse cardiac events (MACEs), restenosis and late lumen loss. Results: Seventy-six studies including more than 15000 patients in randomized controlled trials and over 70000 patients in adjusted observational studies were included. At overall-term follow-up, SES significantly reduced TLR (relative risk [RR]: 0.61; 95% confidence interval [CI]: 0.49–0.76), TVR (RR: 0.67; 95% CI: 0.54–0.83), MACE (RR: 0.79; 95% CI: 0.72–0.87), myocardial infarction (RR: 0.85; 95% CI: 0.73–0.99), in-segment restenosis (RR: 0.50; 95% CI: 0.38–0.65), and in-segment late lumen loss (weighted mean difference [WMD]: −0.19; 95% CI: −0.24–−0.14) in randomized controlled trials compared with PES. In addition, lower rates of death (RR: 0.91; 95% CI: 0.83–1.00), any stent thrombosis (RR: 0.62; 95% CI: 0.45–0.86), definite stent thrombosis (RR: 0.59; 95% CI: 0.45–0.77) were found in patients receiving SES in adjusted observational studies. Largely similar results were found at short- and long-term follow-up, and in patients with diabetes, acute myocardial infarction or long lesions. Conclusions: SES significantly reduced the short-, long- and overall-term risk of TLR/TVR, MACE, and restenosis, and overall-term risk of myocardial infarction in randomized controlled trials, as compared with PES. Lower rates of death and stent thrombosis were also observed in observational studies in SES-treated patients. [ABSTRACT FROM AUTHOR]

Micro RNAs are involved in the regulation of various cellular processes, including cell apoptosis and autophagy. Expression of micro RNA-99a (miR-99a) is reduced in apoptotic neonatal mice ventricular myocytes ( NMVMs) subjected to hypoxia. We hypothesize that miR-99a might restore cardiac function after myocardial infarction ( MI) by up-regulation of myocyte autophagy and apoptosis. We observed down-regulated miR-99a expression in NMVMs exposed to hypoxia using TaqMan quantitative reverse transcriptase-polymerase chain reaction analysis ( RT- PCR). We also observed that miR-99a overexpression decreased hypoxia-mediated apoptosis in cultured NMVMs. To investigate whether overexpression of miR-99a in vivo could improve cardiac function in ischaemic heart, adult C57/BL6 mice undergoing MI were randomized into two groups and were intra-myocardially injected with lenti-99a-green fluorescent protein ( GFP) or lenti- GFP (control). Four weeks after MI, lenti-99a- GFP group showed significant improvement in both left ventricular ( LV) function and survival ratio, as compared to the lenti- GFP group. Histological analysis, western blotting analysis and electron microscopy revealed decreased cellular apoptosis and increased autophagy in cardiomyocytes of lenti-99a- GFP group. Furthermore, western blotting analysis showed inhibited mammalian target of rapamycin (m TOR) expression in the border zones of hearts in miR-99a-treated group. Our results demonstrate that miR-99a overexpression improves both cardiac function and survival ratio in a murine model of MI by preventing cell apoptosis and increasing autophagy via an m TOR/P70/S6K signalling pathway. These findings suggest that miR-99a plays a cardioprotective role in post-infarction LV remodelling and increased expression of miR-99a may have a therapeutic potential in ischaemic heart disease. [ABSTRACT FROM AUTHOR]

Abstract: This study was designed to determine the levels of early endothelial progenitor cells (EPCs), apelin, vascular endothelial growth factor (VEGF) and stromal cell-derived growth factor-1 (SDF-1) after acute myocardial infarction (AMI), and to investigate the relationships between these cytokines and early EPCs. Early EPCs, defined as CD133+, KDR+, and CD34+ cells, were quantified by flow cytometry. The levels of early EPCs and those cytokines in AMI patients were significantly different from those with coronary artery disease or controls (P < 0.05). Plasma apelin levels were inversely correlated with Gensini score and early EPCs (both P < 0.01). Early EPCs, VEGF and SDF-1 showed different patterns of changes in AMI patients during the first 24 h. The trend in the change of early EPCs was proportionally correlated with that of VEGF (P < 0.05). AMI patients exhibited increased early EPCs with remarkably decreased apelin levels and enhanced VEGF levels. [Copyright &y& Elsevier]

The inflammation modulation effects of mesenchymal stromal cell-derived exosomes (MSC-EXO) are well established. We aimed to explore the mechanism behind the inflammatory responses of numerous exosomal cargo molecules that have been neglected in molecular biology research, and to develop an exosomal cargo delivery system that can exert a stronger therapeutic effect on myocardial ischemia-reperfusion (I/R) injury. Computational approaches were used to identify key exosomal miRNAs and their downstream mRNAs that are expressed in the inflammatory response. Direct interactions between miRNA-181a and the c-Fos mRNA complex were confirmed by luciferase reporter assay. MSC-EXO carrying miRNA-181a-overexpressing lentiviruses were intramyocardially injected into a mouse model of myocardial I/R injury. I/R progression was evaluated through echocardiography and immunofluorescence microscopy. miRNA-181a provided substantial coverage against a host of immune-related genes through the miRNA-mRNA network. miRNA-181a delivery by MSC-EXO combined the immune-suppressing effect of miRNA-181a and the cell targeting capability of MSC-EXO to exert a stronger therapeutic effect on myocardium I/R injury. We showed the potential of MSC-EXO as a tool for the specific delivery of small RNAs in vivo. This study shed new light on the potential application of miRNA-181a-overexpressing MSC-EXO as a therapeutic strategy for myocardial I/R injury. [ABSTRACT FROM AUTHOR]

Background: The relationship between elastolytic matrix metalloproteinases (MMPs) (such as MMP-2, MMP-9) and thoracic aortic dissection (TAD) has been described, but little is known regarding the role of collagenolytic MMPs in thoracic aortic dissection. The aim of this study was to determine the role of MMP-8 in acute thoracic aortic dissection. Materials and Methods: Forty-five patients affected by TAD and 40 with acute myocardial infarction (AMI) were recruited into this study. Blood samples within 72 h of the onset of symptoms were available for all the 85 patients. Healthy individuals were selected from the out-patients who complained of chest pain but in whom no cardiovascular diseases were found. Plasma levels of MMP-1, -8, -13 were measured by enzyme-linked immunosorbent assay (ELISA) technique in all subjects. Aortic tissue samples obtained during surgery were evaluated by Western blot for MMP-8 and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression. Results: Plasma MMP-8 levels in patients affected by TAD and AMI were both higher than that in healthy subjects (284.35 ± 96.32 ng/mL and 88.57 ± 26.71 ng/mL versus 75.39 ± 23.36 ng/mL). The difference of the MMP-8 level between TAD patients and healthy subjects was significant (P = 0.000). No significant differences were found in MMP-1 and MMP-13 plasma levels among the three groups. Conclusions: The acute phase of TAD is characterized by a prominent increase of MMP-8 plasma level, which may play a key role in the occurrence of TAD. MMP-8 could be involved in the acute inflammatory reaction and may be a useful marker for the diagnosis of acute TAD. [ABSTRACT FROM AUTHOR]