Cardioprotection during cardiac surgery.
Hausenloy Derek J,Boston-Griffiths Edney,Yellon Derek M
Coronary heart disease (CHD) is the leading cause of morbidity and mortality worldwide. For a large number of patients with CHD, coronary artery bypass graft (CABG) surgery remains the preferred strategy for coronary revascularization. Over the last 10 years, the number of high-risk patients undergoing CABG surgery has increased significantly, resulting in worse clinical outcomes in this patient group. This appears to be related to the ageing population, increased co-morbidities (such as diabetes, obesity, hypertension, stroke), concomitant valve disease, and advances in percutaneous coronary intervention which have resulted in patients with more complex coronary artery disease undergoing surgery. These high-risk patients are more susceptible to peri-operative myocardial injury and infarction (PMI), a major cause of which is acute global ischaemia/reperfusion injury arising from inadequate myocardial protection during CABG surgery. Therefore, novel therapeutic strategies are required to protect the heart in this high-risk patient group. In this article, we review the aetiology of PMI during CABG surgery, its diagnosis and clinical significance, and the endogenous and pharmacological therapeutic strategies available for preventing it. By improving cardioprotection during CABG surgery, we may be able to reduce PMI, preserve left ventricular systolic function, and reduce morbidity and mortality in these high-risk patients with CHD.
Unique morphological characteristics of mitochondrial subtypes in the heart: the effect of ischemia and ischemic preconditioning.
Kalkhoran Siavash Beikoghli,Munro Peter,Qiao Fan,Ong Sang-Bing,Hall Andrew R,Cabrera-Fuentes Hector,Chakraborty Bibhas,Boisvert William A,Yellon Derek M,Hausenloy Derek J
Discoveries (Craiova, Romania)
RATIONALE:Three subsets of mitochondria have been described in adult cardiomyocytes - intermyofibrillar (IMF), subsarcolemmal (SSM), and perinuclear (PN). They have been shown to differ in physiology, but whether they also vary in morphological characteristics is unknown. Ischemic preconditioning (IPC) is known to prevent mitochondrial dysfunction induced by acute myocardial ischemia/reperfusion injury (IRI), but whether IPC can also modulate mitochondrial morphology is not known. AIMS:Morphological characteristics of three different subsets of adult cardiac mitochondria along with the effect of ischemia and IPC on mitochondrial morphology will be investigated. METHODS:Mouse hearts were subjected to the following treatments (N=6 for each group): stabilization only, IPC (3x5 min cycles of global ischemia and reperfusion), ischemia only (20 min global ischemia); and IPC and ischemia. Hearts were then processed for electron microscopy and mitochondrial morphology was assessed subsequently. RESULTS:In adult cardiomyocytes, IMF mitochondria were found to be more elongated and less spherical than PN and SSM mitochondria. PN mitochondria were smaller in size when compared to the other two subsets. SSM mitochondria had similar area to IMF mitochondria but their sphericity measures were similar to PN mitochondria. Ischemia was shown to increase the sphericity parameters of all 3 subsets of mitochondria; reduce the length of IMF mitochondria, and increase the size of PN mitochondria. IPC had no effect on mitochondrial morphology either at baseline or after ischemia. CONCLUSION:The three subsets of mitochondria in the adult heart are morphologically different. IPC does not appear to modulate mitochondrial morphology in adult cardiomyocytes.
Realizing the clinical potential of ischemic preconditioning and postconditioning.
Yellon Derek M,Hausenloy Derek J
Nature clinical practice. Cardiovascular medicine
After an acute myocardial infarction (AMI), early reperfusion by thrombolysis or primary percutaneous coronary intervention remains the most-effective strategy for limiting the size of an evolving infarct. The mortality from AMI, however, remains significant, due partly to the lethal reperfusion injury that occurs on reperfusing the ischemic myocardium. Novel cardioprotective strategies are required to target this form of injury. In ischemic preconditioning transient, nonlethal episodes of myocardial ischemia and reperfusion before the index ischemic episode reduce infarct size. The cardioprotective potential of ischemic preconditioning has not been realized in clinical practice because it necessitates an intervention applied before the onset of AMI, which is difficult to predict. A more-amenable approach to cardioprotection is to intervene at the onset of reperfusion, the timing of which is under the control of the operator. In this regard, ischemic postconditioning, in which transient episodes of myocardial ischemia and reperfusion administered at the onset of reperfusion reduce infarct size, constitutes one such intervention. Interestingly, studies suggest that ischemic preconditioning and postconditioning activate the same signaling pathway at the time of reperfusion, thereby offering a common target for cardioprotection. Therefore, the pharmacologic recruitment of this signaling pathway at the time of myocardial reperfusion might allow one to harness the cardioprotective potential of ischemic preconditioning and postconditioning. In this review, we discuss the potential application of ischemic preconditioning and postconditioning in the clinical arena of myocardial ischemia and reperfusion, and examine the common signaling pathways by which this might be achieved.
Cardioprotective growth factors.
Hausenloy Derek J,Yellon Derek M
Many of the originally identified cardiovascular 'growth factors' have been demonstrated to exert a diverse variety of actions within the cardiovascular system, the majority of which are unrelated to their initially proposed mechanism of action. Interestingly, several of these growth factors have been demonstrated to protect the cardiomyocyte from the detrimental effects of acute ischaemia-reperfusion injury, through the activation of a variety of cell-surface receptors and the subsequent recruitment of a number of intracellular signal transduction pathways, which include components of the reperfusion injury salvage kinase pathway. This article will review several of these cardioprotective growth factors with respect to their ability to confer direct myocardial protection, focusing on the underlying signalling pathways involved and their potential for clinical application.
Preconditioning and postconditioning: united at reperfusion.
Hausenloy Derek J,Yellon Derek M
Pharmacology & therapeutics
Despite current optimal treatment, the morbidity and mortality of coronary heart disease (CHD), the leading cause of death worldwide, remains significant, paving the way for the development of novel cardioprotective therapies. Two potential strategies for protecting the heart are ischemic preconditioning (IPC) and ischemic postconditioning (IPost), which describe the cardioprotection obtained from applying transient episodes of myocardial ischemia and reperfusion either before or after the index ischemic event, respectively. Much progress has been made in elucidating the signal transduction pathway, which underlies their protection. Intriguingly, it is the first few minutes of myocardial reperfusion following the index ischemic period, which appear crucial to both IPC- and IPost-induced protection. Emerging evidence suggests that they appear to recruit a similar signaling pathway at time of myocardial reperfusion, comprising cell-surface receptors, a diverse array of protein kinase cascades including the reperfusion injury salvage kinase (RISK) pathway, redox signaling, and the mitochondrial permeability transition pore (mPTP). The common signaling pathway that appears to unite these 2 cardioprotective strategies at the time of reperfusion is the subject of this review. Importantly, this common cardioprotective pathway can be activated at the time of myocardial reperfusion in the clinical setting using pharmacological agents to target the essential signaling components, which should lead to the development of novel treatment strategies for improving the clinical outcomes of patients with CHD.
Effect of remote ischaemic conditioning on clinical outcomes in patients presenting with an ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.
Hausenloy Derek J,Kharbanda Rajesh,Rahbek Schmidt Michael,Møller Ulla Kristine,Ravkilde Jan,Okkels Jensen Lisette,Engstrøm Thomas,Garcia Ruiz Jose Manuel,Radovanovic Nebosja,Christensen Erica F,Sørensen Henrik Toft,Ramlall Manish,Bulluck Heerajnarain,Evans Richard,Nicholas Jennifer,Knight Rosemary,Clayton Tim,Yellon Derek M,Bøtker Hans Erik
European heart journal
The rationale and study design for the multicentre, randomized, controlled CONDI2/ERIC-PPCI study are discussed.
Effect of remote ischaemic preconditioning on myocardial injury in patients undergoing coronary artery bypass graft surgery: a randomised controlled trial.
Hausenloy Derek J,Mwamure Peter K,Venugopal Vinod,Harris Joanne,Barnard Matthew,Grundy Ernie,Ashley Elizabeth,Vichare Sanjeev,Di Salvo Carmelo,Kolvekar Shyam,Hayward Martin,Keogh Bruce,MacAllister Raymond J,Yellon Derek M
Lancet (London, England)
BACKGROUND:Whether remote ischaemic preconditioning, an intervention in which brief ischaemia of one tissue or organ protects remote organs from a sustained episode of ischaemia, is beneficial for patients undergoing coronary artery bypass graft surgery is unknown. We did a single-blinded randomised controlled study to establish whether remote ischaemic preconditioning reduces myocardial injury in these patients. METHODS:57 adult patients undergoing elective coronary artery bypass graft surgery were randomly assigned to either a remote ischaemic preconditioning group (n=27) or to a control group (n=30) after induction of anaesthesia. Remote ischaemic preconditioning consisted of three 5-min cycles of right upper limb ischaemia, induced by an automated cuff-inflator placed on the upper arm and inflated to 200 mm Hg, with an intervening 5 min of reperfusion during which the cuff was deflated. Serum troponin-T concentration was measured before surgery and at 6, 12, 24, 48, and 72 h after surgery. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00397163. FINDINGS:Remote ischaemic preconditioning significantly reduced overall serum troponin-T release at 6, 12, 24, and 48 h after surgery. The total area under the curve was reduced by 43%, from 36.12 microg/L (SD 26.08) in the control group to 20.58 microg/L (9.58) in the remote ischaemic preconditioning group (mean difference 15.55 [SD 5.32]; 95% CI 4.88-26.21; p=0.005). INTERPRETATION:We have shown that adult patients undergoing elective coronary artery bypass graft surgery at a single tertiary centre could benefit from remote ischaemic preconditioning, using transient upper limb ischaemia.
Inhibiting mitochondrial fission protects the heart against ischemia/reperfusion injury.
Ong Sang-Bing,Subrayan Sapna,Lim Shiang Y,Yellon Derek M,Davidson Sean M,Hausenloy Derek J
BACKGROUND:Whether alterations in mitochondrial morphology affect the susceptibility of the heart to ischemia/reperfusion injury is unknown. We hypothesized that modulating mitochondrial morphology protects the heart against ischemia/reperfusion injury. METHODS AND RESULTS:In response to ischemia, mitochondria in HL-1 cells (a cardiac-derived cell line) undergo fragmentation, a process that is dependent on the mitochondrial fission protein dynamin-related protein 1 (Drp1). Transfection of HL-1 cells with the mitochondrial fusion proteins mitofusin 1 or 2 or with Drp1(K38A), a dominant-negative mutant form of Drp1, increased the percentage of cells containing elongated mitochondria (65+/-4%, 69+/-5%, and 63+/-6%, respectively, versus 46+/-6% in control: n=80 cells per group; P<0.05), decreased mitochondrial permeability transition pore sensitivity (by 2.4+/-0.5-, 2.3+/-0.7-, and 2.4+/-0.3-fold, respectively; n=80 cells per group; P<0.05), and reduced cell death after simulated ischemia/reperfusion injury (11.6+/-3.9%, 16.2+/-3.9%, and 12.1+/-2.9%, respectively, versus 41.8+/-4.1% in control: n=320 cells per group; P<0.05). Treatment of HL-1 cells with mitochondrial division inhibitor-1, a pharmacological inhibitor of Drp1, replicated these beneficial effects. Interestingly, elongated interfibrillar mitochondria were identified in the adult rodent heart with confocal and electron microscopy, and in vivo treatment with mitochondrial division inhibitor-1 increased the percentage of elongated mitochondria from 3.6+/-0.5% to 14.5+/-2.8% (P=0.023). Finally, treatment of adult murine cardiomyocytes with mitochondrial division inhibitor-1 reduced cell death and inhibited mitochondrial permeability transition pore opening after simulated ischemia/reperfusion injury, and in vivo treatment with mitochondrial division inhibitor-1 reduced myocardial infarct size in mice subject to coronary artery occlusion and reperfusion (21.0+/-2.2% with mitochondrial division inhibitor-1 versus 48.0+/-4.5% in control; n=6 animals per group; P<0.05). CONCLUSIONS:Inhibiting mitochondrial fission protects the heart against ischemia/reperfusion injury, suggesting a novel pharmacological strategy for cardioprotection.
Myocardial reperfusion injury: looking beyond primary PCI.
Fröhlich Georg M,Meier Pascal,White Steven K,Yellon Derek M,Hausenloy Derek J
European heart journal
Coronary heart disease (CHD) is the leading cause of death and disability in Europe. For patients presenting with an acute ST-segment elevation myocardial infarction (STEMI), timely myocardial reperfusion using either thrombolytic therapy or primary percutaneous coronary intervention (PPCI) is the most effective therapy for limiting myocardial infarct (MI) size, preserving left-ventricular systolic function and reducing the onset of heart failure. Despite this, the morbidity and mortality of STEMI patients remain significant, and novel therapeutic interventions are required to improve clinical outcomes in this patient group. Paradoxically, the process of myocardial reperfusion can itself induce cardiomyocyte death-a phenomenon which has been termed 'myocardial reperfusion injury' (RI), the irreversible consequences of which include microvascular obstruction and myocardial infarction. Unfortunately, there is currently no effective therapy for preventing myocardial RI in STEMI patients making it an important residual target for cardioprotection. Previous attempts to translate cardioprotective therapies (antioxidants, calcium-channel blockers, and anti-inflammatory agents) for reducing RI into the clinic, have been unsuccessful. An improved understanding of the pathophysiological mechanisms underlying RI has resulted in the identification of several promising mechanical (ischaemic post-conditioning, remote ischaemic pre-conditioning, therapeutic hypothermia, and hyperoxaemia), and pharmacological (atrial natriuretic peptide, cyclosporin-A, and exenatide) therapeutic strategies, for preventing myocardial RI, many of which have shown promise in initial proof-of-principle clinical studies. In this article, we review the pathophysiology underlying myocardial RI, and highlight the potential therapeutic interventions which may be used in the future to prevent RI and improve clinical outcomes in patients with CHD.
Myocardial ischemia-reperfusion injury: a neglected therapeutic target.
Hausenloy Derek J,Yellon Derek M
The Journal of clinical investigation
Acute myocardial infarction (MI) is a major cause of death and disability worldwide. In patients with MI, the treatment of choice for reducing acute myocardial ischemic injury and limiting MI size is timely and effective myocardial reperfusion using either thombolytic therapy or primary percutaneous coronary intervention (PPCI). However, the process of reperfusion can itself induce cardiomyocyte death, known as myocardial reperfusion injury, for which there is still no effective therapy. A number of new therapeutic strategies currently under investigation for preventing myocardial reperfusion injury have the potential to improve clinical outcomes in patients with acute MI treated with PPCI.
Clinical manifestations and basic mechanisms of myocardial ischemia/reperfusion injury.
Ci ji yi xue za zhi = Tzu-chi medical journal
Acute myocardial ischemia/reperfusion (I/R) injury is a significant, unsolved clinical puzzle. In the disease context of acute myocardial infarction, reperfusion remains the only effective strategy to salvage ischemic myocardium, but it also causes additional damage. Myocardial I/R injury is composed of four types of damage, and these events attenuate the benefits of reperfusion therapy. Thus, inventing new strategies to conquer I/R injury is an unmet clinical need. A variety of pathological processes and mediators, including changes in the pH, generation of reactive oxygen radicals, and intracellular calcium overload, are proposed to be crucial in I/R-related cell injury. Among the intracellular events that occur during I/R, we stress the importance of protein phosphorylation signaling and elaborate its regulation. A variety of protein kinase pathways could be activated in I/R, including reperfusion injury salvage kinase and survivor-activating factor enhancement pathways, which are critical to cardiomyocyte survival. In addition to serine/threonine phosphorylation signaling, protein tyrosine phosphorylation is also critical in multiple cell functions and survival. However, the roles of protein kinases and phosphatases in I/R have not been extensively studied yet. By better understanding the mechanisms of I/R injury, we may have a better chance to develop new strategies for I/R injury and apply them in the clinical patient care.
The Long Noncoding RNA Landscape of the Ischemic Human Left Ventricle.
Saddic Louis A,Sigurdsson Martin I,Chang Tzuu-Wang,Mazaika Erica,Heydarpour Mahyar,Shernan Stanton K,Seidman Christine E,Seidman Jon G,Aranki Sary F,Body Simon C,Muehlschlegel Jochen D
Circulation. Cardiovascular genetics
BACKGROUND:The discovery of functional classes of long noncoding RNAs (lncRNAs) has expanded our understanding of the variety of RNA species that exist in cells. In the heart, lncRNAs have been implicated in the regulation of development, ischemic and dilated cardiomyopathy, and myocardial infarction. Nevertheless, there is a limited description of expression profiles for these transcripts in human subjects. METHODS AND RESULTS:We obtained left ventricular tissue from human patients undergoing cardiac surgery and used RNA sequencing to describe an lncRNA profile. We then identified a list of lncRNAs that were differentially expressed between pairs of samples before and after the ischemic insult of cardiopulmonary bypass. The expression of some of these lncRNAs correlates with ischemic time. Coding genes in close proximity to differentially expressed lncRNAs and coding genes that have coordinated expression with these lncRNAs are enriched in functional categories related to myocardial infarction, including heart function, metabolism, the stress response, and the immune system. CONCLUSIONS:We describe a list of lncRNAs that are differentially expressed after ischemia in the human heart. These genes are predicted to function in pathways consistent with myocardial injury. As a result, lncRNAs may serve as novel diagnostic and therapeutic targets for ischemic heart disease. CLINICAL TRIAL REGISTRATION:URL: http://www.clinicaltrials.gov. Unique identifier: NCT00985049.
Transcriptome analysis reveals distinct patterns of long noncoding RNAs in heart and plasma of mice with heart failure.
Li Danhua,Chen Geng,Yang Jichun,Fan Xiaofang,Gong Yongsheng,Xu Guoheng,Cui Qinghua,Geng Bin
OBJECTIVE:To assess the global changes in and characteristics of the transcriptome of long noncoding RNAs (LncRNAs) in heart tissue, whole blood and plasma during heart failure (HF) and association with expression of paired coding genes. METHODS:Here we used microarray assay to examine the transcriptome of LncRNAs deregulated in the heart, whole blood, and plasma during HF in mice. We confirmed the changes in LncRNAs by quantitative PCR. RESULTS:We revealed and confirmed a number of LncRNAs that were deregulated during HF, which suggests a potential role of LncRNAs in HF. Strikingly, the patterns of expression of LncRNA differed between plasma and other tissue during HF. LncRNA expression was associated with LncRNA length in all samples but not in plasma during HF, which suggests that the global association of LncRNA expression and LncRNA length in plasma could be biomarkers for HF. In total, 32 LncRNAs all expressed in the heart, whole blood and plasma showed changed expression with HF, so they may be biomarkers in HF. In addition, sense-overlapped LncRNAs tended to show consistent expression with their paired coding genes, whereas antisense-overlapped LncRNAs tended to show the opposite expression in plasma; so different types of LncRNAs may have different characteristics in HF. Interestingly, we revealed an inverse correlation between changes in expression of LncRNAs in plasma and in heart, so circulating levels of LncRNAs may not represent just passive leakage from the HF heart but also active regulation or release of circulatory cells or other cells during HF. CONCLUSIONS:We reveal stable expression of LncRNAs in plasma during HF, which suggests a newly described component in plasma. The distinct expression patterns of circulatory LncRNAs during HF indicate that LncRNAs may actively respond to stress and thus serve as biomarkers of HF diagnosis and treatment.
Methylation of p15INK4b and expression of ANRIL on chromosome 9p21 are associated with coronary artery disease.
Zhuang Jianhui,Peng Wenhui,Li Hailing,Wang Wei,Wei Yidong,Li Weiming,Xu Yawei
BACKGROUND:Genome-wide association studies have identified that multiple single nucleiotide polymorphisms on chromosome 9p21 are tightly associated with coronary artery disease (CAD). However, the mechanism linking this risk locus to CAD remains unclear. METHODOLOGY/PRINCIPAL FINDINGS:The methylation status of six candidate genes (BAX, BCL-2, TIMP3, p14(ARF), p15(INK4b) and p16(INK4a)) in 205 patients and controls who underwent coronary angiography were analyzed by quantitative MethyLight assay. Rs10757274 was genotyped and expression of INK4/ARF and antisense non-coding RNA in the INK4 locus (ANRIL) was determined by real-time RT-PCR. Compared with controls, DNA methylation levels at p15(INK4b) significantly increased in CAD patients (p = 0.006). To validate and dissect the methylation percentage of each target CpG site at p15(INK4b), pyrosequencing was performed, finding CpG +314 and +332 remarkably hypermethylated in CAD patients. Further investigation determined that p15(INK4b) hypermethylation prevalently emerged in lymphocytes of CAD patients (p = 0.013). The rs10757274 genotype was significantly associated with CAD (p = 0.003) and GG genotype carriers had a higher level of ANRIL exon 1-5 expression compared among three genotypes (p = 0.009). There was a stepwise increase in p15(INK4b) and p16(INK4a) methylation as ANRIL exon 1-5 expression elevated (r = 0.23, p = 0.001 and r = 0.24, p = 0.001, respectively), although neither of two loci methylation was directly linked to rs10757274 genotype. CONCLUSIONS/SIGNIFICANCE:p15(INK4b) methylation is associated with CAD and ANRIL expression. The epigenetic changes in p15(INK4b) methylation and ANRIL expression may involve in the mechanisms of chromosome 9p21 on CAD development.
Resequencing and clinical associations of the 9p21.3 region: a comprehensive investigation in the Framingham heart study.
Johnson Andrew D,Hwang Shih-Jen,Voorman Arend,Morrison Alanna,Peloso Gina M,Hsu Yi-Hsiang,Thanassoulis George,Newton-Cheh Christopher,Rogers Ian S,Hoffmann Udo,Freedman Jane E,Fox Caroline S,Psaty Bruce M,Boerwinkle Eric,Cupples L Adrienne,O'Donnell Christopher J
BACKGROUND:9p21.3 is among the most strongly replicated regions for cardiovascular disease. There are few reports of sequencing the associated 9p21.3 interval. We set out to sequence the 9p21.3 region followed by a comprehensive study of genetic associations with clinical and subclinical cardiovascular disease and its risk factors, as well as with copy number variation and gene expression, in the Framingham Heart Study (FHS). METHODS AND RESULTS:We sequenced 281 individuals (94 with myocardial infarction, 94 with high coronary artery calcium levels, and 93 control subjects free of elevated coronary artery calcium or myocardial infarction), followed by genotyping and association in >7000 additional FHS individuals. We assessed genetic associations with clinical and subclinical cardiovascular disease, risk factor phenotypes, and gene expression levels of the protein-coding genes CDKN2A and CDKN2B and the noncoding gene ANRIL in freshly harvested leukocytes and platelets. Within this large sample, we found strong associations of 9p21.3 variants with increased risk for myocardial infarction, higher coronary artery calcium levels, and larger abdominal aorta diameters and no evidence for association with traditional cardiovascular disease risk factors. No common protein-coding variation, variants in splice donor or acceptor sites, or copy number variation events were observed. By contrast, strong associations were observed between genetic variants and gene expression, particularly for a short isoform of ANRIL and for CDKN2B. CONCLUSIONS:Our thorough genomic characterization of 9p21.3 suggests common variants likely account for observed disease associations and provides further support for the hypothesis that complex regulatory variation affecting ANRIL and CDKN2B gene expression may contribute to increased risk for clinically apparent and subclinical coronary artery disease and aortic disease.
Identification of new susceptibility loci for type 2 diabetes and shared etiological pathways with coronary heart disease.
Zhao Wei,Rasheed Asif,Tikkanen Emmi,Lee Jung-Jin,Butterworth Adam S,Howson Joanna M M,Assimes Themistocles L,Chowdhury Rajiv,Orho-Melander Marju,Damrauer Scott,Small Aeron,Asma Senay,Imamura Minako,Yamauch Toshimasa,Chambers John C,Chen Peng,Sapkota Bishwa R,Shah Nabi,Jabeen Sehrish,Surendran Praveen,Lu Yingchang,Zhang Weihua,Imran Atif,Abbas Shahid,Majeed Faisal,Trindade Kevin,Qamar Nadeem,Mallick Nadeem Hayyat,Yaqoob Zia,Saghir Tahir,Rizvi Syed Nadeem Hasan,Memon Anis,Rasheed Syed Zahed,Memon Fazal-Ur-Rehman,Mehmood Khalid,Ahmed Naveeduddin,Qureshi Irshad Hussain,Tanveer-Us-Salam ,Iqbal Wasim,Malik Uzma,Mehra Narinder,Kuo Jane Z,Sheu Wayne H-H,Guo Xiuqing,Hsiung Chao A,Juang Jyh-Ming J,Taylor Kent D,Hung Yi-Jen,Lee Wen-Jane,Quertermous Thomas,Lee I-Te,Hsu Chih-Cheng,Bottinger Erwin P,Ralhan Sarju,Teo Yik Ying,Wang Tzung-Dau,Alam Dewan S,Di Angelantonio Emanuele,Epstein Steve,Nielsen Sune F,Nordestgaard Børge G,Tybjaerg-Hansen Anne,Young Robin, ,Benn Marianne,Frikke-Schmidt Ruth,Kamstrup Pia R, , , ,Jukema J Wouter,Sattar Naveed,Smit Roelof,Chung Ren-Hua,Liang Kae-Woei,Anand Sonia,Sanghera Dharambir K,Ripatti Samuli,Loos Ruth J F,Kooner Jaspal S,Tai E Shyong,Rotter Jerome I,Chen Yii-Der Ida,Frossard Philippe,Maeda Shiro,Kadowaki Takashi,Reilly Muredach,Pare Guillaume,Melander Olle,Salomaa Veikko,Rader Daniel J,Danesh John,Voight Benjamin F,Saleheen Danish
To evaluate the shared genetic etiology of type 2 diabetes (T2D) and coronary heart disease (CHD), we conducted a genome-wide, multi-ancestry study of genetic variation for both diseases in up to 265,678 subjects for T2D and 260,365 subjects for CHD. We identify 16 previously unreported loci for T2D and 1 locus for CHD, including a new T2D association at a missense variant in HLA-DRB5 (odds ratio (OR) = 1.29). We show that genetically mediated increase in T2D risk also confers higher CHD risk. Joint T2D-CHD analysis identified eight variants-two of which are coding-where T2D and CHD associations appear to colocalize, including a new joint T2D-CHD association at the CCDC92 locus that also replicated for T2D. The variants associated with both outcomes implicate new pathways as well as targets of existing drugs, including icosapent ethyl and adipocyte fatty-acid-binding protein.
Long noncoding RNAs in cardiac development and pathophysiology.
Schonrock Nicole,Harvey Richard P,Mattick John S
Heart function requires sophisticated regulatory networks to orchestrate organ development, physiological responses, and environmental adaptation. Until recently, it was thought that these regulatory networks are composed solely of protein-mediated transcriptional control and signaling systems; consequently, it was thought that cardiac disease involves perturbation of these systems. However, it is becoming evident that RNA, long considered to function primarily as the platform for protein production, may in fact play a major role in most, if not all, aspects of gene regulation, especially the epigenetic processes that underpin organogenesis. These include not only well-validated classes of regulatory RNAs, such as microRNAs, but also tens of thousands of long noncoding RNAs that are differentially expressed across the entire genome of humans and other animals. Here, we review this emerging landscape, summarizing what is known about their functions and their role in cardiac biology, and provide a toolkit to assist in exploring this previously hidden layer of gene regulation that may underpin heart adaptation and complex heart diseases.
LncRNA-mRNA competing endogenous RNA network depicts transcriptional regulation in ischaemia reperfusion injury.
Liu Hongying,Xu Danping,Zhong Xin,Xu Dongsheng,Chen Geng,Ge Junbo,Li Hua
Journal of cellular and molecular medicine
The study aimed to investigate time-course transcriptomes in myocardial ischaemia reperfusion injury (IRI) via RNA-Seq. Transcriptomes of 10 samples derived from patients with acute ST-segment elevation myocardial infarction (ASTEMI) who were assigned to percutaneous coronary intervention (PCI), were sequenced at the time of 0 (before PCI), 2, 12, 24 and 72 hours after PCI, respectively. Using the genefilter package in r, wgcna and stem, different expression lncRNA (DEL) and mRNA (DEM) were analysed. Out of 756 mRNAs and 206 lncRNAs shared by enrolled patients, 135 RNAs were screened to be significantly associated with the IRI. Furthermore, combined with lncRNA-mRNA, lncRNA-miRNA and miRNA-mRNA network, 51 RNAs and 131 relationship pairs were ascertained in the competing endogenous RNAs (ceRNA) network. Among these nodes, SH2D3C and GTF2H4 were significantly enriched in cellular response to stress and their interaction module were isolated from functional ceRNA network. Subsequently, their critical role was confirmed via down-regulation of SH2D3C and GTF2H4 expression in vitro model. These results identified that lncRNA-mRNA ceRNA network, associated significantly with IRI, functioned as critical regulative pivotal roles after PCI-AMI, and SH2D3C and GTF2H4 may be the most responsive transcriptional regulator in the early-phase of IRI.
Long Noncoding RNAs: From Clinical Genetics to Therapeutic Targets?
Boon Reinier A,Jaé Nicolas,Holdt Lesca,Dimmeler Stefanie
Journal of the American College of Cardiology
Recent studies suggest that the majority of the human genome is transcribed, but only about 2% accounts for protein-coding exons. Long noncoding RNAs (lncRNAs) constitute a heterogenic class of RNAs that includes, for example, intergenic lncRNAs, antisense transcripts, and enhancer RNAs. Moreover, alternative splicing can lead to the formation of circular RNAs. In support of putative functions, GWAS for cardiovascular diseases have shown predictive single-nucleotide polymorphisms in lncRNAs, such as the 9p21 susceptibility locus that encodes the lncRNA antisense noncoding RNA in the INK4 locus (ANRIL). Many lncRNAs are regulated during disease. For example, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and myocardial infarction-associated transcript (MIAT) were shown to affect endothelial cell functions and diabetic retinopathy, whereas lincRNA-p21 controls neointima formation. In the heart, several lncRNAs were shown to act as microRNA sponges and to control ischemia-reperfusion injury or act as epigenetic regulators. In this review, the authors summarize the current understanding of lncRNA functions and their role as biomarkers in cardiovascular diseases.
LncRNA MALAT1 Promotes Oxygen-Glucose Deprivation and Reoxygenation Induced Cardiomyocytes Injury Through Sponging miR-20b to Enhance beclin1-Mediated Autophagy.
Wang Shuang,Yao Tao,Deng Fan,Yu Wenqian,Song Yiting,Chen Jingyi,Ruan Zhihua
Cardiovascular drugs and therapy
BACKGROUND/AIMS:LncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is reported to be highly expressed in myocardial I/R injury and closely related to autophagy. However, the exact biological role of MALAT1 and its underlying mechanism in myocardial I/R injury remain to be elucidated. METHODS:We established incultured H9C2 cardiomyocytes an oxygen-glucose deprivation and reoxygenation (OGD/R) model for 6 h and then reoxygen-glucose for 4 h. We measured cell damage and autophagy levels after OGD/R by real-time quantitative PCR and Western blot. The relationships between miR-20b and MALAT1, beclin1 were confirmed by luciferase reporter assay. RESULTS:We found that the expression of MALAT1 and beclin1, cell damage levels (lactate dehydrogenase (LDH) release, 222.4 ± 29.4 vs. 577.5 ± 27.4 U/L; creatine kinase MB isoenzyme (CK-MB), 1.0 ± 0.2 vs. 4.3 ± 0.4; cardiac troponin I (cTn-I), 1.0 ± 0.3 vs. 3.0 ± 0.3; p < 0.05), and autophagy levels were significantly increased after OGD/R model, while cell viability (100.0 vs. 54.2 ± 2.2%, p < 0.05) and the expression of miR-20b and P62 were reduced; the trend of all the above data was significantly reversed by MALAT1 siRNA. In addition, the luciferase reporter assay results confirmed that MALAT1 directly binds to miR-20b-5p and functions as a ceRNA for miR-20b-5p to regulate beclin1. As a result, MALAT1 overexpression antagonized while MALAT1 knockdown enhanced the inhibitory effects of miR-20b-5p on beclin1-related cardiomyocytes autophagy in OGD/R injury. CONCLUSION:LncRNA MALAT1 promotes OGD/R-induced cardiomyocytes injury through sponging miR-20b to enhance beclin1-mediated autophagy.
LINC-PINT Activates the Mitogen-Activated Protein Kinase Pathway to Promote Acute Myocardial Infarction by Regulating miR-208a-3p.
Zhu Jianzhong,Gu Huimin,Lv Xiaolei,Yuan Chunying,Ni Ping,Liu Feng
Circulation journal : official journal of the Japanese Circulation Society
BACKGROUND:This study is performed to explore the differential expression of long intergenic non-coding-p53 induced non-coding transcript, miR-208a-3p and JUN in acute myocardial infarction (AMI) and their potential mechanisms. Methods and Results: Gene Expression Omnibus, R software, Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) analysis were used for analyzing the differentially expressed genes (DEGs) and pathways. The differential expressions of LINC-PINT and miR-208a-3p were examined by qRT-PCR. The expressions of JUN and the mitogen-activated protein kinase (MAPK) pathway-related proteins were analyzed by Western blot. The triphenyltetrazolium chloride (TTC) staining and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) staining methods were used to measure the myocardial infarction size and tissue apoptosis respectively. The targeted relationships between miR-208a-3p and LINC-PINT or JUN were confirmed using a dual luciferase reporter assay. DEGs were significantly enriched in the MAPK signaling pathway. LINC-PINT could sponge miR-208a-3p, which targeted and regulated JUN. LINC-PINT and JUN were confirmed to be overexpressed in AMI tissues. Silencing LINC-PINT and JUN could exert a protective influence against AMI. The expression of miR-208a-3p was significantly decreased in AMI tissues, and miR-208a-3p reduced myocardial ischemia-reperfusion injury and apoptosis. Downregulation of LINC-PINT facilitated miR-208a-3p expression and suppressed the protein level of JUN, contributing to the inactivation of the MAPK pathway in the AMI tissues and thus generating protective effects. CONCLUSIONS:Knockdown of LINC-PINT inactivated the MAPK pathway by releasing miR-208a-3p and suppressing the JUN, protecting the injury during the process of AMI.
Inhibition of LncRNA-HRIM Increases Cell Viability by Regulating Autophagy Levels During Hypoxia/Reoxygenation in Myocytes.
Huang Zhouqing,Ye Bozhi,Wang Zhengxian,Han Jibo,Lin Lu,Shan Peiren,Cai Xueli,Huang Weijian
Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology
Backgrund/Aims: Ischemia reperfusion (I/R) promotes the severity of cardiomyocyte injury. Long noncoding RNAs (LncRNAs) are key regulators in cardiovascular diseases. However, the association between LncRNAs and myocardial I/R injury has not been thoroughly characterized to date. We attempted to clarify the potential biological role of a LncRNA (E230034O05Rik), which we named hypoxia/reoxygenation (H/R) injury-related factor in myocytes (HRIM), by investigating the differential expression of LncRNAs between groups of myocytes exposed to either a normal level of oxygen or to H/R. METHODS:Microarray analysis was used to determine analyze the global differential expression of LncRNAs in H9c2 myocytes exposed either to a normal level of oxygen or to H/R. Target LncRNA levels were further verified in vitro and ex vivo by real-time polymerase chain reaction (qPCR). Cell viability was analyzed using the Cell Counting Kit-8 assay. Autophagy levels were confirmed by Western blotting, transmission electron microscopy, and autophagic double-labeled (mRFP-GFP-LC3) adenovirus analyses. RESULTS:Gene expression profiling revealed that 797 LncRNAs and 1898 mRNAs were differentially expressed in the H/R group compared with the normal oxygen group. Among these LncRNAs and mRNAs, 6 upregulated LncRNAs and 2 downregulated LncRNAs in the H/R group were selected and further validated by qPCR in vitro and ex vivo. Additionally, LncRNA-HRIM was inhibited by specific siRNAs in H9c2 myocytes exposed to H/R. The inhibition of LncRNA-HRIM by siRNA prevented cell death by suppressing excessive autophagic activity in myocytes, This finding suggests a detrimental role of LncRNA-HRIM in the regulation of I/R injury. CONCLUSIONS:LncRNAs are involved in H/R injury of H9c2 myocytes. Inhibition of LncRNA-HRIM increased cell viability by reducing autophagy in myocytes during H/R.
Inhibition of lncRNA TUG1 upregulates miR-142-3p to ameliorate myocardial injury during ischemia and reperfusion via targeting HMGB1- and Rac1-induced autophagy.
Su Qiang,Liu Yang,Lv Xiang-Wei,Ye Zi-Liang,Sun Yu-Han,Kong Bing-Hui,Qin Zhen-Bai
Journal of molecular and cellular cardiology
BACKGROUND:Long non-coding RNAs (lncRNAs) play a central role in regulating heart diseases. In the present study, we examined the effects of lncRNA taurine up-regulated gene 1 (TUG1) in ischemia/reperfusion (I/R)- or hydrogen peroxide-challenged cardiomyocytes, with specific focus on autophagy-induced cell apoptosis. METHODS:The expressions of miR-142-3p and TUG1 in HO-challenged cardiomyocytes and I/R-injured heart tissue were measured by RT-qPCR. Cell death was measured by trypan blue staining assay. Cell apoptosis was determined by Annexin V/PI staining and TUNEL assay. Autophagy was examined by quantifying cells or tissues containing LC3 autophagic vacuoles by immunofluorescence, or by measuring the expressions of autophagy-related biomarkers by Western blot. The direct interaction between miR-142-3p and TUG1, high mobility group box 1 protein (HMGB1), or Ras-related C3 botulinum toxin substrate 1 (Rac1) was examined using luciferase reporter assay. The significance of miR-142-3p and TUG1 on cell apoptosis or autophagy was examined using both gain-of-function and loss-of-function approaches. The importance of HMGB1 or Rac1 was assessed using siRNA-mediated gene silencing. RESULTS:miR-142-3p was down-regulated, while TUG1 up-regulated in HO-challenged cardiomyocytes in vitro and I/R-injured heart tissues in vivo. Functionally, inhibition of TUG1 and overexpression of miR-142-3p inhibited cell apoptosis and autophagy in cardiomyocytes. The function of TUG1 were achieved by sponging miR-142-3p and releasing the suppression of the putative targets of miR-142-3p, HMGB1 and Rac1. Both HMGB1 and Rac1 essentially mediated cell apoptosis and autophagy induced by TUG1. CONCLUSIONS:TUG1, by targeting miR-142-3p and up-regulating HMGB1 and Rac1, plays a central role in stimulating autophagic cell apoptosis in ischemia/hypoxia-challenged cardiomyocytes. Down-regulating TUG1 or up-regulating miR-142-3p may ameliorate myocardial injury and protect against acute myocardial infarction.
LncRNA CAIF inhibits autophagy and attenuates myocardial infarction by blocking p53-mediated myocardin transcription.
Liu Cui-Yun,Zhang Yu-Hui,Li Rui-Bei,Zhou Lu-Yu,An Tao,Zhang Rong-Cheng,Zhai Mei,Huang Yan,Yan Kao-Wen,Dong Yan-Han,Ponnusamy Murugavel,Shan Chan,Xu Sheng,Wang Qi,Zhang Yan-Hui,Zhang Jian,Wang Kun
Increasing evidence suggests that long noncoding RNAs (lncRNAs) play crucial roles in various biological processes. However, little is known about the effects of lncRNAs on autophagy. Here we report that a lncRNA, termed cardiac autophagy inhibitory factor (CAIF), suppresses cardiac autophagy and attenuates myocardial infarction by targeting p53-mediated myocardin transcription. Myocardin expression is upregulated upon HO and ischemia/reperfusion, and knockdown of myocardin inhibits autophagy and attenuates myocardial infarction. p53 regulates cardiomyocytes autophagy and myocardial ischemia/reperfusion injury by regulating myocardin expression. CAIF directly binds to p53 protein and blocks p53-mediated myocardin transcription, which results in the decrease of myocardin expression. Collectively, our data reveal a novel CAIF-p53-myocardin axis as a critical regulator in cardiomyocyte autophagy, which will be potential therapeutic targets in treatment of defective autophagy-associated cardiovascular diseases.
The lncRNA ROR/miR-124-3p/TRAF6 axis regulated the ischaemia reperfusion injury-induced inflammatory response in human cardiac myocytes.
Liang Ying-Ping,Liu Qin,Xu Guo-Hai,Zhang Jing,Chen Yong,Hua Fu-Zhou,Deng Chang-Qing,Hu Yan-Hui
Journal of bioenergetics and biomembranes
Myocardial ischaemia reperfusion injury (MIRI) is considered the primary cause of death in patients with cardiovascular diseases. Recently, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have been found to be involved in the pathogenesis of MIRI. However, whether lncRNA ROR and miR-124-3p play roles in MIRI and the underlying mechanism remain undetermined. HCMs were exposed to hypoxic conditions for 2 h followed by re-oxygenation (H/R) treatment. Expression of miR-124-3p and lncRNA ROR in HCMs was measured by qRT-PCR. TRAF6 expression was evaluated by qRT-PCR and western blotting. ELISA and qRT-PCR were conducted to assess the production of TNF-α, IL-6, and IL-1β. The interaction between miR-124-3p and TRAF6, as well as between miR-124-3p and lncRNA ROR, was verified by dual-luciferase reporter assay. Cell apoptosis was detected by flow cytometry analysis. Our data revealed that miR-124-3p was significantly downregulated, while TRAF6 and lncRNA ROR were upregulated in both MIRI rat model and H/R treated HCMs. Overexpression of miR-124-3p reversed the H/R-induced cell apoptosis and upregulation of TNF-α, IL-6, and IL-1β. Mechanistically, miR-124-3p bound and negatively regulated TRAF6 expression in HCMs. Moreover, TRAF6 overexpression significantly blocked the effects of miR-124-3p mimics on cell apoptosis and inflammatory response of HCMs, which involved the NF-κB pathway. Further analysis showed that lncRNA ROR sponged and negatively regulated miR-124-3p in HCMs. Overexpression of IL-1β was demonstrated to promote H/R induced cell apoptosis in HCMs. In addition, overexpression of ROR further enhanced the H/R-induced inflammation and cell apoptosis through its action on miR-124-3p. The lncRNA ROR/miR-124-3p/TRAF6 axis regulated the H/R-induced cell apoptosis and inflammatory response of HCMs.
MicroRNA-103/107 Regulate Programmed Necrosis and Myocardial Ischemia/Reperfusion Injury Through Targeting FADD.
Wang Jian-Xun,Zhang Xiao-Jie,Li Qian,Wang Kun,Wang Yin,Jiao Jian-Qin,Feng Chang,Teng Sun,Zhou Lu-Yu,Gong Ying,Zhou Zhi-Xia,Liu Jia,Wang Jian-Ling,Li Pei-feng
RATIONALE:Necrosis is one of the main forms of cardiomyocyte death in heart disease. Recent studies have demonstrated that certain types of necrosis are regulated and programmed dependent on the activation of receptor-interacting serine/threonine-protein kinase (RIPK) 1 and 3 which may be negatively regulated by Fas-associated protein with death domain (FADD). In addition, microRNAs and long noncoding RNAs have been shown to play important roles in various biological processes recently. OBJECTIVE:The purpose of this study was to test the hypothesis that microRNA-103/107 and H19 can participate in the regulation of RIPK1- and RIPK3-dependent necrosis in fetal cardiomyocyte-derived H9c2 cells and myocardial infarction through targeting FADD. METHODS AND RESULTS:Our results show that FADD participates in H2O2-induced necrosis by influencing the formation of RIPK1 and RIPK3 complexes in H9c2 cells. We further demonstrate that miR-103/107 target FADD directly. Knockdown of miR-103/107 antagonizes necrosis in the cellular model and also myocardial infarction in a mouse ischemia/reperfusion model. The miR-103/107-FADD pathway does not participate in tumor necrosis factor-α-induced necrosis. In exploring the molecular mechanism by which miR-103/107 are regulated, we show that long noncoding RNA H19 directly binds to miR-103/107 and regulates FADD expression and necrosis. CONCLUSIONS:Our results reveal a novel myocardial necrosis regulation model, which is composed of H19, miR-103/107, and FADD. Modulation of their levels may provide a new approach for preventing myocardial necrosis.
The long noncoding RNA NRF regulates programmed necrosis and myocardial injury during ischemia and reperfusion by targeting miR-873.
Wang K,Liu F,Liu C-Y,An T,Zhang J,Zhou L-Y,Wang M,Dong Y-H,Li N,Gao J-N,Zhao Y-F,Li P-F
Cell death and differentiation
Emerging evidences suggest that necrosis is programmed and is one of the main forms of cell death in the pathological process in cardiac diseases. Long noncoding RNAs (lncRNAs) are emerging as new players in gene regulation. However, it is not yet clear whether lncRNAs can regulate necrosis in cardiomyocytes. Here, we report that a long noncoding RNA, named necrosis-related factor (NRF), regulates cardiomyocytes necrosis by targeting miR-873 and RIPK1 (receptor-interacting serine/threonine-protein kinase 1)/RIPK3 (receptor-interacting serine/threonine-protein kinase 3). Our results show that RIPK1 and RIPK3 participate in H2O2-induced cardiomyocytes necrosis. miR-873 suppresses the translation of RIPK1/RIPK3 and inhibits RIPK1/RIPK3-mediated necrotic cell death in cardiomyocytes. miR-873 reduces myocardial infarct size upon ischemia/reperfusion (I/R) injury in the animal model. In exploring the molecular mechanism by which miR-873 expression is regulated, we identify NRF as an endogenous sponge RNA and repress miR-873 expression. NRF directly binds to miR-873 and regulates RIPK1/RIPK3 expression and necrosis. Knockdown of NRF antagonizes necrosis in cardiomyocytes and reduces necrosis and myocardial infarction upon I/R injury. Further, we identify that p53 transcriptionally activates NRF expression. P53 regulates cardiomyocytes necrosis and myocardial I/R injury through NRF and miR-873.Our results identify a novel mechanism involving NRF and miR-873 in regulating programmed necrosis in the heart and suggest a potential therapeutic avenue for cardiovascular diseases.
Long Noncoding RNAs: New Players in Ischaemia-Reperfusion Injury.
Yu Si-Yang,Tang Liang,Zhou Sheng-Hua
Heart, lung & circulation
Long noncoding RNAs (lncRNAs) constitute a new class of noncoding RNAs that interfere with gene expression. It has been shown that lncRNAs exert comprehensive effects on biological processes and are associated with numerous diseases such as cancer. However, the possible role of lncRNAs in ischaemia/reperfusion (I/R) injury have received relatively little attention. Accumulating evidence indicates that lncRNAs are also involved in the progression of I/R injury such as myocardial, cerebral, hepatic, renal and mesenteric I/R injury. In this review, we summarise the current knowledge of lncRNAs in I/R injury, attempting to better explain the molecular mechanism of I/R injury and provide new directions for its therapy.
Suppression of long noncoding RNA NEAT1 attenuates hypoxia-induced cardiomyocytes injury by targeting miR-378a-3p.
Zhao Jiali,Chen Fudi,Ma Wei,Zhang Peng
BACKGROUND/AIMS:lncRNA NEAT1 is involved in the development of many diseases. However, the function of lncRNA NEAT1 in myocardial infarction is unclear. Therefore, this experimental design based on lncRNA NEAT1 to explore the pathogenesis of myocardial infarction. METHODS:RT-qPCR was used to detect the expression of lncRNA NEAT1 and miR-378a-3p in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. MTT assay, flow cytometry, Caspase-3 kit and transwell assay were used to detect the effects of lncRNA NEAT1 and miR-378a-3p on cardiomyocyte proliferation, apoptosis and migration. Target gene prediction and screening, luciferase reporter assays were used to verify downstream target genes for lncRNA NEAT1 and miR-378a-3p. Western blotting was used to detect the protein expression of Atg12 and related autophagy genes. RESULTS:lncRNA NEAT1 was highly expressed in peripheral blood and mouse cardiomyocytes of patients with myocardial infarction. Moreover, lncRNA NEAT1 significantly promoted cell proliferation and migration of cardiomyocytes. In addition, lncRNA NEAT1 inhibited miR-378a-3p expression, and miR-378a-3p inhibited Atg12 expression, while lncRNA NEAT1 regulated expression of Atg12 and related autophagic factors via miR-378a-3p. Knockout of microRNA-378-3p reversed the effects of NEAT1 silencing on cell damage. CONCLUSION:lncRNA NEAT1 can regulate the proliferation of cardiomyocytes by regulating miR-378-3p/Atg12 axis, thus accelerating the occurrence and development of cardiomyocytes.
Insight into long noncoding RNA-miRNA-mRNA axes in myocardial ischemia-reperfusion injury: the implications for mechanism and therapy.
Xiong Wei,Qu Yan,Chen Hongmei,Qian Jinqiao
Emerging evidence has demonstrated that regulatory noncoding RNAs (ncRNAs), such as long noncoding RNAs (lncRNAs) and miRNAs, play crucial roles in the initiation and progress of myocardial ischemia-reperfusion injury (MIRI), which is associated with autophagy, apoptosis and necrosis of cardiomyocytes, as well as oxidative stress, inflammation and mitochondrial dysfunction. LncRNAs serve as a precursor or host of miRNAs and directly/indirectly affecting miRNAs via competitive binding or sponge effects. Simultaneously, miRNAs post-transcriptionally regulate the expression of genes by targeting various mRNA sequences due to their imperfect pairing with mRNAs. This review summarizes the potential regulatory role of lncRNA-miRNA-mRNA axes in MIRI and related molecular mechanisms of cardiac disorders, also provides insight into the potential therapies for MIRI-induced diseases.
Long non-coding RNA-ROR aggravates myocardial ischemia/reperfusion injury.
Zhang Weiwei,Li Ying,Wang Peng
Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas
Long non-coding RNAs (lncRNAs) play an important role in the pathogenesis of cardiovascular diseases, especially in myocardial infarction and ischemia/reperfusion (I/R). However, the underlying molecular mechanism remains unclear. In this study, we determined the role and the possible underlying molecular mechanism of lncRNA-ROR in myocardial I/R injury. H9c2 cells and human cardiomyocytes (HCM) were subjected to either hypoxia/reoxygenation (H/R), I/R or normal conditions (normoxia). The expression levels of lncRNA-ROR were detected in serum of myocardial I/R injury patients, H9c2 cells, and HCM by qRT-PCR. Then, levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) were measured by kits. Cell viability, apoptosis, apoptosis-associated factors, and p38/MAPK pathway were examined by MTT, flow cytometry, and western blot assays. Furthermore, reactive oxygen species (ROS) production was determined by H2DCF-DA and MitoSOX Red probes with flow cytometry. NADPH oxidase activity and NOX2 protein levels were measured by lucigenin chemiluminescence and western blot. Results showed that lncRNA-ROR expression was increased in I/R patients and in H/R treatment of H9c2 cells and HCM. Moreover, lncRNA-ROR significantly promoted H/R-induced myocardial injury via stimulating release of LDH, MDA, SOD, and GSH-PX. Furthermore, lncRNA-ROR decreased cell viability, increased apoptosis, and regulated expression of apoptosis-associated factors. Additionally, lncRNA-ROR increased phosphorylation of p38 and ERK1/2 expression and inhibition of p38/MAPK, and rescued lncRNA-ROR-induced cell injury in H9c2 cells and HCM. ROS production, NADPH oxidase activity, and NOX2 protein levels were promoted by lncRNA-ROR. These data suggested that lncRNA-ROR acted as a therapeutic agent for the treatment of myocardial I/R injury.
Long Noncoding RNA AK12348 is Involved in the Regulation of Myocardial Ischaemia-Reperfusion Injury by Targeting PARP and Caspase-3.
Zheng Chengfei,Wu Ziheng,Tian Lu,Li Donglin,Wang Xiaohui,He Yunjun,He Yangyan,Jin Wei,Li Ming,Zhu Qianqian,Shang Tao,Zhang Hongkun
Heart, lung & circulation
BACKGROUD:Recently long non-coding RNAs (lncRNAs) have attracted attention in several biomedical fields. The purpose of this study is to investigate the profile of myocardial lncRNAs and their potential roles in myocardial ischaemia-reperfusion injury (IRI). METHODS:EdgeR bioconductor package was used to screen differentially expressed lncRNAs in myocardial IRI, and lncRNA AK12348 was selected. The mRNA levels of lncRNA AK12348 in normal and anoxia/reoxygenation (A/R) cardiomyocytes were determined by qRT-PCR. After transfection with siRNA-lncRNA, AK12348, LDH release and cell apoptotic rates in normal and A/R cardiomyocytes were determined. The protein expression values of PARP and Caspase-3 were also determined by western blotting. RESULTS:The relative level of lncRNA AK12348, LDH release and cell apoptotic rate in A/R cardiomyocytes was significantly higher than that in normal cardiomyocytes. After transfection with siRNA-lncRNA AK12348, LDH release and cell apoptotic rates in A/R cardiomyocytes were reduced, while the values in normal cardiomyocytes had almost no change. The protein expression values of PARP and Caspase-3 in A/R cardiomyocytes were much higher than the Control. After knockdown of lncRNA AK12348, the values decreased. CONCLUSION:Long non-coding RNAs AK12348 could be potential therapeutic targets for the treatment of myocardial IRI.
Expression profiling and ontology analysis of long noncoding RNAs in post-ischemic heart and their implied roles in ischemia/reperfusion injury.
Liu Youbin,Li Guangnan,Lu Huimin,Li Wei,Li Xianglu,Liu Huimin,Li Xingda,Li Tianyu,Yu Bo
Long noncoding RNAs (lncRNAs) play important regulatory roles in cellular physiology. The contributions of lncRNAs to ischemic heart disease remain largely unknown. The aim of this study was to investigate the profile of myocardial lncRNAs and their potential roles at early stage of reperfusion. lncRNAs and mRNAs were profiled by microarray and the expression of some highly-dysregulated lncRNAs was further validated using polymerase chain reaction. Our results revealed that 64 lncRNAs were up-regulated and 87 down-regulated, while 50 mRNAs were up-regulated and 60 down-regulated in infarct region at all reperfusion sampled. Gene ontology analysis indicated that dysregulated transcripts were associated with immune response, spermine catabolic process, taxis, chemotaxis, polyamine catabolic process, spermine metabolic process, chemokine activity and chemokine receptor binding. Target gene-related pathway analysis showed significant changes in cytokine-cytokine receptor interaction, the chemokine signaling pathway and nucleotide oligomerization domain (NOD)-like receptor signaling pathway which have a close relationship with myocardial ischemia/reperfusion injury (MI/RI). Besides, a gene co-expression network was constructed to identify correlated targets of 10 highly-dysregulated lncRNAs. These lncRNAs may play their roles by this network in post-ischemic heart. Such results provide a foundation for understanding the roles and mechanisms of myocardial lncRNAs at early stage of reperfusion.
Non-coding RNAs as therapeutic targets for preventing myocardial ischemia-reperfusion injury.
Ong Sang-Bing,Katwadi Khairunnisa,Kwek Xiu-Yi,Ismail Nur Izzah,Chinda Kroekkiat,Ong Sang-Ging,Hausenloy Derek J
Expert opinion on therapeutic targets
INTRODUCTION:New treatments are required to improve clinical outcomes in patients with acute myocardial infarction (AMI), for reduction of myocardial infarct (MI) size and preventing heart failure. Following AMI, acute ischemia/reperfusion injury (IRI) ensues, resulting in cardiomyocyte death and impaired cardiac function. Emerging studies have implicated a fundamental role for non-coding RNAs (microRNAs [miRNA], and more recently long non-coding RNAs [lncRNA]) in the setting of acute myocardial IRI. Areas covered: In this article, we discuss the roles of miRNAs and lncRNAs as potential biomarkers and therapeutic targets for the detection and treatment of AMI, review their roles as mediators and effectors of cardioprotection, particularly in the settings of interventions such as ischemic pre- and post-conditioning (IPC & IPost) as well as remote ischemic conditioning (RIC), and highlight future strategies for targeting ncRNAs to reduce MI size and prevent heart failure following AMI. Expert opinion: Investigating the roles of miRNAs and lncRNAs in the setting of AMI has provided new insights into the pathophysiology underlying acute myocardial IRI, and has identified novel biomarkers and therapeutic targets for detecting and treating AMI. Pharmacological and genetic manipulation of these ncRNAs has the therapeutic potential to improve clinical outcomes in AMI patients.