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Slone S, Anthony SR, Green LC, Nieman ML, Alam P, Wu X, Roy S, Aube J, Xu L, Lorenz JN, Owens AP, Kanisicak O, Tranter M. HuR inhibition reduces post-ischemic cardiac remodeling by dampening acute inflammatory gene expression and the innate immune response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.17.524420. [PMID: 36711986 PMCID: PMC9882229 DOI: 10.1101/2023.01.17.524420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Myocardial ischemia/reperfusion (I/R) injury and the resulting cardiac remodeling is a common cause of heart failure. The RNA binding protein Human Antigen R (HuR) has been previously shown to reduce cardiac remodeling following both I/R and cardiac pressure overload, but the full extent of the HuR-dependent mechanisms within cells of the myocardium have yet to be elucidated. In this study, we applied a novel small molecule inhibitor of HuR to define the functional role of HuR in the acute response to I/R injury and gain a better understanding of the HuR-dependent mechanisms during post-ischemic myocardial remodeling. Our results show an early (two hours post-I/R) increase in HuR activity that is necessary for early inflammatory gene expression by cardiomyocytes in response to I/R. Surprisingly, despite the reductions in early inflammatory gene expression at two hours post-I/R, HuR inhibition has no effect on initial infarct size at 24-hours post-I/R. However, in agreement with previously published work, we do see a reduction in pathological remodeling and preserved cardiac function at two weeks post-I/R upon HuR inhibition. RNA-sequencing analysis of neonatal rat ventricular myocytes (NRVMs) at two hours post-LPS treatment to model damage associated molecular pattern (DAMP)-mediated activation of toll like receptors (TLRs) demonstrates a broad HuR-dependent regulation of pro-inflammatory chemokine and cytokine gene expression in cardiomyocytes. We show that conditioned media from NRVMs pre-treated with HuR inhibitor loses the ability to induce inflammatory gene expression in bone marrow derived macrophages (BMDMs) compared to NRVMs treated with LPS alone. Functionally, HuR inhibition in NRVMs also reduces their ability to induce endocrine migration of peripheral blood monocytes in vitro and reduces post-ischemic macrophage infiltration to the heart in vivo. In summary, these results suggest a HuR-dependent expression of pro-inflammatory gene expression by cardiomyocytes that leads to subsequent monocyte recruitment and macrophage activation in the post-ischemic myocardium.
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Molecular Mechanism of Sevoflurane Preconditioning Based on Whole-transcriptome Sequencing of Lipopolysaccharide-induced Cardiac Dysfunction in Mice. J Cardiovasc Pharmacol 2022; 79:846-857. [PMID: 35266915 DOI: 10.1097/fjc.0000000000001259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/22/2022] [Indexed: 11/27/2022]
Abstract
ABSTRACT Sevoflurane, a widely used inhalation anesthetic, has been shown to be cardioprotective in individuals with sepsis and myocardial dysfunction. However, the exact mechanism has not been completely explained. In this study, we performed whole-transcriptome profile analysis in the myocardium of lipopolysaccharide-induced septic mice after sevoflurane pretreatment. RNA transcriptome sequencing showed that 97 protein coding RNAs (mRNAs), 64 long noncoding RNAs (lncRNAs), and 27 microRNAs (miRNAs) were differentially expressed between the lipopolysaccharide and S_L groups. Functional enrichment analysis revealed that target genes for the differentially expressed mRNAs between the 2 groups participated in protein processing in the endoplasmic reticulum, antigen processing and presentation, and the mitogen-activated protein kinase signaling pathway. The bioinformatics study of differentially expressed mRNAs revealed that 13 key genes including Hsph1, Otud1, Manf, Gbp2b, Stip1, Gbp3, Hspa1b, Aff3, Med12, Kdm4a, Gatad1, Cdkn1a, and Ppp1r16b are related to the heart or inflammation. Furthermore, the competing endogenous RNA network revealed that 3 of the 13 key genes established the lncRNA-miRNA-mRNA network (ENSMUST00000192774 --- mmu-miR-7a-5p --- Hspa1b, TCONS_00188587 --- mmu-miR-204-3p --- Aff3 and ENSMUST00000138273 --- mmu-miR-1954 --- Ppp1r16b) may be associated with cardioprotection in septic mice. In general, the findings identified 11 potential essential genes (Hsph1, Otud1, Manf, Gbp2b, Stip1, Gbp3, Hspa1b, Aff3, Med12, Kdm4a, Gatad1, Cdkn1a, and Ppp1r16b) and mitogen-activated protein kinase signaling pathway involved in sevoflurane-induced cardioprotection in septic mice. In particular, sevoflurane may prevent myocardial injury by regulating the lncRNA-miRNA-mRNA network, including (ENSMUST00000192774-mmu-miR-7a-5p-Hspa1b, TCONS_00188587-mmu-miR-204-3p-Aff3, and ENSMUST00000138273-mmu-miR-1954-Ppp1r16b networks), which may be a novel mechanism of sevoflurane-induced cardioprotection.
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Zhang Y, Song C, Ni W, Pei Q, Wang C, Ying Y, Yao M. HSP70 Ameliorates Septic Acute Kidney Injury via Binding with TRAF6 to Inhibit of Inflammation-Mediated Apoptosis. J Inflamm Res 2022; 15:2213-2228. [PMID: 35411167 PMCID: PMC8994667 DOI: 10.2147/jir.s352717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/25/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose Methods Results Conclusion
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Affiliation(s)
- Yiqiu Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Chenlu Song
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Wei Ni
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, People’s Republic of China
| | - Qing Pei
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Caixia Wang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Youguo Ying
- Department of Intensive Care Unit, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
| | - Min Yao
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China
- Correspondence: Min Yao; Youguo Ying, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, 639 Zhizaoju Road, Shanghai, 200011, People’s Republic of China, Email ;
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Naryzhnaya NV, Maslov LN, Derkachev IA, Ma H, Zhang Y, Prasad NR, Singh N, Fu F, Pei JM, Sarybaev A, Sydykov A. The effect of adaptation to hypoxia on cardiac tolerance to ischemia/reperfusion. J Biomed Res 2022:1-25. [PMID: 37183617 PMCID: PMC10387748 DOI: 10.7555/jbr.36.20220125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The acute myocardial infarction (AMI) and sudden cardiac death (SCD), both associated with acute cardiac ischemia, are one of the leading causes of adult death in economically developed countries. The development of new approaches for the treatment and prevention of AMI and SCD remains the highest priority for medicine. A study on the cardiovascular effects of chronic hypoxia (CH) may contribute to the development of these methods. Chronic hypoxia exerts both positive and adverse effects. The positive effects are the infarct-reducing, vasoprotective, and antiarrhythmic effects, which can lead to the improvement of cardiac contractility in reperfusion. The adverse effects are pulmonary hypertension and right ventricular hypertrophy. This review presents a comprehensive overview of how CH enhances cardiac tolerance to ischemia/reperfusion. It is an in-depth analysis of the published data on the underlying mechanisms, which can lead to future development of the cardioprotective effect of CH. A better understanding of the CH-activated protective signaling pathways may contribute to new therapeutic approaches in an increase of cardiac tolerance to ischemia/reperfusion.
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Sun J, Niu C, Ye W, An N, Chen G, Huang X, Wang J, Chen X, Shen Y, Huang S, Wang Y, Wang X, Wang Y, Jin L, Cong W, Li X. FGF13 Is a Novel Regulator of NF-κB and Potentiates Pathological Cardiac Hypertrophy. iScience 2020; 23:101627. [PMID: 33089113 PMCID: PMC7567043 DOI: 10.1016/j.isci.2020.101627] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 08/13/2020] [Accepted: 09/25/2020] [Indexed: 12/31/2022] Open
Abstract
FGF13 is an intracellular FGF factor. Its role in cardiomyopathies has been rarely investigated. We revealed that endogenous FGF13 is up-regulated in cardiac hypertrophy accompanied by increased nuclear localization. The upregulation of FGF13 plays a deteriorating role both in hypertrophic cardiomyocytes and mouse hearts. Mechanistically, FGF13 directly interacts with p65 by its nuclear localization sequence and co-localizes with p65 in the nucleus in cardiac hypertrophy. FGF13 deficiency inhibits NF-κB activation in ISO-treated NRCMs and TAC-surgery mouse hearts, whereas FGF13 overexpression shows the opposite trend. Moreover, FGF13 overexpression alone is sufficient to activate NF-κB in cardiomyocytes. The interaction between FGF13 and p65 or the effects of FGF13 on NF-κB have nothing to do with IκB. Together, an IκB-independent mechanism for NF-κB regulation has been revealed in cardiomyocytes both under basal and stressful conditions, suggesting the promising application of FGF13 as a therapeutic target for pathological cardiac hypertrophy and heart failure. Endogenous FGF13 is up-regulated in cardiomyocytes under pressure overload FGF13 directly interacts with p65 Forced FGF13 overexpression activates NF-κB in cardiomyocytes
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Affiliation(s)
- Jia Sun
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Chao Niu
- Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Weijian Ye
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Ning An
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Gen Chen
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Xiaozhong Huang
- Department of Pediatric Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Jianan Wang
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Xixi Chen
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Yingjie Shen
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Shuai Huang
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Ying Wang
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Xu Wang
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Yang Wang
- Department of Histology and Embryology, Institute of Neuroscience, Wenzhou Medical University Wenzhou, 325000, China
| | - Litai Jin
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Weitao Cong
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
| | - Xiaokun Li
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou 325000, China
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Fang Z, Sun Y, Zhang X, Wang G, Li Y, Wang Y, Zhang Z. Responses of HSP70 Gene to Vibrio parahaemolyticus Infection and Thermal Stress and Its Transcriptional Regulation Analysis in Haliotis diversicolor. Molecules 2019; 24:E162. [PMID: 30609869 PMCID: PMC6337134 DOI: 10.3390/molecules24010162] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/04/2018] [Accepted: 12/17/2018] [Indexed: 02/08/2023] Open
Abstract
Heat-shock protein 70 (HSP70) is a molecular chaperone that plays critical roles in cell protein folding and metabolism, which helps to protect cells from unfavorable environmental stress. Haliotis diversicolor is one of the most important economic breeding species in the coastal provinces of south China. To date, the expression and transcriptional regulation of HSP70 in Haliotis diversicolor (HdHSP70) has not been well characterized. In this study, the expression levels of HdHSP70 gene in different tissues and different stress conditions were detected. The results showed that the HdHSP70 gene was ubiquitously expressed in sampled tissues and was the highest in hepatopancreas, followed by hemocytes. In hepatopancreas and hemocytes, the HdHSP70 gene was significantly up-regulated by Vibrio parahaemolyticus infection, thermal stress, and combined stress (Vibrio parahaemolyticus infection and thermal stress combination), indicating that HdHSP70 is involved in the stress response and the regulation of innate immunity. Furthermore, a 2383 bp of 5'-flanking region sequence of the HdHSP70 gene was cloned, and it contains a presumed core promoter region, a CpG island, a (TG)39 simple sequence repeat (SSR), and many potential transcription factor binding sites. The activity of HdHSP70 promoter was evaluated by driving the expression of luciferase gene in HEK293FT cells. A series of experimental results indicated that the core promoter region is located between -189 bp and +46 bp, and high-temperature stress can increase the activity of HdHSP70 promoter. Sequence-consecutive deletions of the luciferase reporter gene in HEK293FT cells revealed two possible promoter activity regions. To further identify the binding site of the key transcription factor in the two regions, two expression vectors with site-directed mutation were constructed. The results showed that the transcriptional activity of NF-1 site-directed mutation was significantly increased (p < 0.05), whereas the transcriptional activity of NF-κB site-directed mutation was significantly reduced. These results suggest that NF-1 and NF-κB may be two important transcription factors that regulate the expression of HdHSP70 gene.
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Affiliation(s)
- Zhiqiang Fang
- Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, China.
| | - Yulong Sun
- College of Animal Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Xin Zhang
- College of Animal Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Guodong Wang
- Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, China.
| | - Yuting Li
- Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, China.
| | - Yilei Wang
- Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, China.
| | - Ziping Zhang
- College of Animal Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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Guerrero Orriach JL, Escalona Belmonte JJ, Ramirez Aliaga M, Ramirez Fernandez A, Raigón Ponferrada A, Rubio Navarro M, Cruz Mañas J. Anesthetic-induced Myocardial Conditioning: Molecular Fundamentals and Scope. Curr Med Chem 2018; 27:2147-2160. [PMID: 30259804 DOI: 10.2174/0929867325666180926161427] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 08/03/2018] [Accepted: 09/05/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND The pre- and post-conditioning effects of halogenated anesthetics make them most suitable for cardiac surgery. Several studies have demonstrated that the mechanism of drug-induced myocardial conditioning is enzyme-mediated via messenger RNA and miRNA regulation. The objective of this study was to investigate the role that miRNAs play in the cardioprotective effect of halogenated anesthetics. For such purpose, we reviewed the literature to determine the expression profile of miRNAs in ischemic conditioning and in the complications prevented by these phenomena. METHODS A review was conducted of more than 100 studies to identify miRNAs involved in anesthetic-induced myocardial conditioning. Our objective was to determine the miRNAs that play a relevant role in ischemic disease, heart failure and arrhythmogenesis, which expression is modulated by the perioperative administration of halogenated anesthetics. So far, no studies have been performed to assess the role of miRNAs in anesthetic-induced myocardial conditioning. The potential of miRNAs as biomarkers and miRNAs-based therapies involving the synthesis, inhibition or stimulation of miRNAs are a promising avenue for future research in the field of cardiology. RESULTS Each of the cardioprotective effects of myocardial conditioning is related to the expression of several (not a single) miRNAs. The cumulative evidence on the role of miRNAs in heart disease and myocardial conditioning opens new therapeutic and diagnostic opportunities. CONCLUSION Halogenated anesthetics regulate the expression of miRNAs involved in heart conditions. Further research is needed to determine the expression profile of miRNAs after the administration of halogenated drugs. The results of these studies would contribute to the development of new hypnotics for cardiac surgery patients.
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Affiliation(s)
- Jose Luis Guerrero Orriach
- Institute of Biomedical Research in Malaga [IBIMA], Malaga, Spain.,Department of Cardio- Anaesthesiology, Virgen de la Victoria University Hospital, Malaga, Spain.,Department of Pharmacology and Pediatrics, School of Medicine, University of Malaga, Malaga, Spain
| | | | - Marta Ramirez Aliaga
- Department of Cardio- Anaesthesiology, Virgen de la Victoria University Hospital, Malaga, Spain
| | | | - Aida Raigón Ponferrada
- Department of Cardio- Anaesthesiology, Virgen de la Victoria University Hospital, Malaga, Spain
| | - Manuel Rubio Navarro
- Department of Cardio- Anaesthesiology, Virgen de la Victoria University Hospital, Malaga, Spain
| | - Jose Cruz Mañas
- Department of Cardio- Anaesthesiology, Virgen de la Victoria University Hospital, Malaga, Spain
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Song Y, Zhong C, Wang X. Heat shock protein 70: A promising therapeutic target for myocardial ischemia–reperfusion injury. J Cell Physiol 2018; 234:1190-1207. [DOI: 10.1002/jcp.27110] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/29/2018] [Indexed: 12/30/2022]
Affiliation(s)
- Yan‐Jun Song
- Guangdong Provincial Biomedical Engineering Technology Research Center for Cardiovascular Disease, Sino‐Japanese Cooperation Platform for Translational Research in Heart Failure, Laboratory of Heart Center, Department of Cardiology, Heart Center, Zhujiang Hospital Southern Medical University Guangzhou China
- School of Laboratory Medicine and Biotechnology Southern Medical University Guangzhou China
| | - Chong‐Bin Zhong
- Guangdong Provincial Biomedical Engineering Technology Research Center for Cardiovascular Disease, Sino‐Japanese Cooperation Platform for Translational Research in Heart Failure, Laboratory of Heart Center, Department of Cardiology, Heart Center, Zhujiang Hospital Southern Medical University Guangzhou China
| | - Xian‐Bao Wang
- Guangdong Provincial Biomedical Engineering Technology Research Center for Cardiovascular Disease, Sino‐Japanese Cooperation Platform for Translational Research in Heart Failure, Laboratory of Heart Center, Department of Cardiology, Heart Center, Zhujiang Hospital Southern Medical University Guangzhou China
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Exosomal miR-21a-5p mediates cardioprotection by mesenchymal stem cells. J Mol Cell Cardiol 2018; 119:125-137. [DOI: 10.1016/j.yjmcc.2018.04.012] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 04/02/2018] [Accepted: 04/21/2018] [Indexed: 12/22/2022]
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Aljakna A, Fracasso T, Sabatasso S. Molecular tissue changes in early myocardial ischemia: from pathophysiology to the identification of new diagnostic markers. Int J Legal Med 2018; 132:425-438. [DOI: 10.1007/s00414-017-1750-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 11/20/2017] [Indexed: 02/06/2023]
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The Slo(w) path to identifying the mitochondrial channels responsible for ischemic protection. Biochem J 2017; 474:2067-2094. [PMID: 28600454 DOI: 10.1042/bcj20160623] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/10/2017] [Accepted: 02/13/2017] [Indexed: 12/19/2022]
Abstract
Mitochondria play an important role in tissue ischemia and reperfusion (IR) injury, with energetic failure and the opening of the mitochondrial permeability transition pore being the major causes of IR-induced cell death. Thus, mitochondria are an appropriate focus for strategies to protect against IR injury. Two widely studied paradigms of IR protection, particularly in the field of cardiac IR, are ischemic preconditioning (IPC) and volatile anesthetic preconditioning (APC). While the molecular mechanisms recruited by these protective paradigms are not fully elucidated, a commonality is the involvement of mitochondrial K+ channel opening. In the case of IPC, research has focused on a mitochondrial ATP-sensitive K+ channel (mitoKATP), but, despite recent progress, the molecular identity of this channel remains a subject of contention. In the case of APC, early research suggested the existence of a mitochondrial large-conductance K+ (BK, big conductance of potassium) channel encoded by the Kcnma1 gene, although more recent work has shown that the channel that underlies APC is in fact encoded by Kcnt2 In this review, we discuss both the pharmacologic and genetic evidence for the existence and identity of mitochondrial K+ channels, and the role of these channels both in IR protection and in regulating normal mitochondrial function.
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Gidlöf O, Johnstone AL, Bader K, Khomtchouk BB, O'Reilly JJ, Celik S, Van Booven DJ, Wahlestedt C, Metzler B, Erlinge D. Ischemic Preconditioning Confers Epigenetic Repression of Mtor and Induction of Autophagy Through G9a-Dependent H3K9 Dimethylation. J Am Heart Assoc 2016; 5:JAHA.116.004076. [PMID: 28007739 PMCID: PMC5210409 DOI: 10.1161/jaha.116.004076] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background Ischemic preconditioning (IPC) protects the heart from prolonged ischemic insult and reperfusion injury through a poorly understood mechanism. Post‐translational modifications of histone residues can confer rapid and drastic switches in gene expression in response to various stimuli, including ischemia. The aim of this study was to investigate the effect of histone methylation in the response to cardiac ischemic preconditioning. Methods and Results We used cardiac biopsies from mice subjected to IPC to quantify global levels of 3 of the most well‐studied histone methylation marks (H3K9me2, H3K27me3, and H3K4me3) with Western blot and found that H3K9me2 levels were significantly increased in the area at risk compared to remote myocardium. In order to assess which genes were affected by the increase in H3K9me2 levels, we performed ChIP‐Seq and transcriptome profiling using microarray. Two hundred thirty‐seven genes were both transcriptionally repressed and enriched in H3K9me2 in the area at risk of IPC mice. Of these, Mtor (Mechanistic target of rapamycin) was chosen for mechanistic studies. Knockdown of the major H3K9 methyltransferase G9a resulted in a significant decrease in H3K9me2 levels across Mtor, increased Mtor expression, as well as decreased autophagic activity in response to rapamycin and serum starvation. Conclusions IPC confers an increase of H3K9me2 levels throughout the Mtor gene—a master regulator of cellular metabolism and a key player in the cardioprotective effect of IPC—leading to transcriptional repression via the methyltransferase G9a. The results of this study indicate that G9a has an important role in regulating cardiac autophagy and the cardioprotective effect of IPC.
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Affiliation(s)
- Olof Gidlöf
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| | - Andrea L Johnstone
- The Center for Therapeutic Innovation and Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL
| | - Kerstin Bader
- Department of Internal Medicine III/Cardiology, Innsbruck Medical University, Innsbruck, Austria
| | - Bohdan B Khomtchouk
- The Center for Therapeutic Innovation and Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL
| | - Jiaqi J O'Reilly
- The Center for Therapeutic Innovation and Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL
| | - Selvi Celik
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
| | - Derek J Van Booven
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL
| | - Claes Wahlestedt
- The Center for Therapeutic Innovation and Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL
| | - Bernhard Metzler
- Department of Internal Medicine III/Cardiology, Innsbruck Medical University, Innsbruck, Austria
| | - David Erlinge
- Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden
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Roles of HIF-1α, VEGF, and NF-κB in Ischemic Preconditioning-Mediated Neuroprotection of Hippocampal CA1 Pyramidal Neurons Against a Subsequent Transient Cerebral Ischemia. Mol Neurobiol 2016; 54:6984-6998. [DOI: 10.1007/s12035-016-0219-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 10/12/2016] [Indexed: 10/20/2022]
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14
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Ashton KJ, Reichelt ME, Mustafa SJ, Teng B, Ledent C, Delbridge LMD, Hofmann PA, Morrison RR, Headrick JP. Transcriptomic effects of adenosine 2A receptor deletion in healthy and endotoxemic murine myocardium. Purinergic Signal 2016; 13:27-49. [PMID: 27696085 DOI: 10.1007/s11302-016-9536-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 09/09/2016] [Indexed: 12/25/2022] Open
Abstract
Influences of adenosine 2A receptor (A2AR) activity on the cardiac transcriptome and genesis of endotoxemic myocarditis are unclear. We applied transcriptomic profiling (39 K Affymetrix arrays) to identify A2AR-sensitive molecules, revealed by receptor knockout (KO), in healthy and endotoxemic hearts. Baseline cardiac function was unaltered and only 37 A2AR-sensitive genes modified by A2AR KO (≥1.2-fold change, <5 % FDR); the five most induced are Mtr, Ppbp, Chac1, Ctsk and Cnpy2 and the five most repressed are Hp, Yipf4, Acta1, Cidec and Map3k2. Few canonical paths were impacted, with altered Gnb1, Prkar2b, Pde3b and Map3k2 (among others) implicating modified G protein/cAMP/PKA and cGMP/NOS signalling. Lipopolysaccharide (LPS; 20 mg/kg) challenge for 24 h modified >4100 transcripts in wild-type (WT) myocardium (≥1.5-fold change, FDR < 1 %); the most induced are Lcn2 (+590); Saa3 (+516); Serpina3n (+122); Cxcl9 (+101) and Cxcl1 (+89) and the most repressed are Car3 (-38); Adipoq (-17); Atgrl1/Aplnr (-14); H19 (-11) and Itga8 (-8). Canonical responses centred on inflammation, immunity, cell death and remodelling, with pronounced amplification of toll-like receptor (TLR) and underlying JAK-STAT, NFκB and MAPK pathways, and a 'cardio-depressant' profile encompassing suppressed ß-adrenergic, PKA and Ca2+ signalling, electromechanical and mitochondrial function (and major shifts in transcripts impacting function/injury including Lcn2, S100a8/S100a9, Icam1/Vcam and Nox2 induction, and Adipoq, Igf1 and Aplnr repression). Endotoxemic responses were selectively modified by A2AR KO, supporting inflammatory suppression via A2AR sensitive shifts in regulators of NFκB and JAK-STAT signalling (IκBζ, IκBα, STAT1, CDKN1a and RRAS2) without impacting the cardio-depressant gene profile. Data indicate A2ARs exert minor effects in un-stressed myocardium and selectively suppress NFκB and JAK-STAT signalling and cardiac injury without influencing cardiac depression in endotoxemia.
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Affiliation(s)
- Kevin J Ashton
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia
| | - Melissa E Reichelt
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - S Jamal Mustafa
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | - Bunyen Teng
- Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
| | | | - Lea M D Delbridge
- Department of Physiology, University of Melbourne, Parkville, VIC, Australia
| | - Polly A Hofmann
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - R Ray Morrison
- Division of Critical Care Medicine, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - John P Headrick
- Heart Foundation Research Center, Griffith University, Southport, QLD, 4217, Australia.
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15
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Yang B, Yan P, Gong H, Zuo L, Shi Y, Guo J, Guo R, Xie J, Li B. TWEAK protects cardiomyocyte against apoptosis in a PI3K/AKT pathway dependent manner. Am J Transl Res 2016; 8:3848-3860. [PMID: 27725864 PMCID: PMC5040682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 08/30/2016] [Indexed: 06/06/2023]
Abstract
Myocyte apoptosis is a key determinant of cardiac recovery and prognosis of patients with acute myocardial infarction (AMI). Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), a member of TNF superfamily, is a pro-inflammatory and pro-angiogenic cytokine implicated in physiological tissue regeneration and wound repair and is closely related to cardiac remodeling, dysfunction and fibrosis. However, the role of TWEAK and its receptor Fn14 in the cardiomyocyte apoptosis is still poorly understood. The present study aimed to investigate whether the TWEAK enhanced the cardiomyocyte apoptosis in AMI. The apoptosis of the cardiomyocyte cell line H9C2 was induced by hypoxia/reoxygenation. The apoptosis of H9C2 cells was evaluated by flow cytometry and caspase-3 activity assay under treatment with TWEAK at different concentrations. The phosphorylated signaling molecules and the expression involved in the surprising protection of TWEAK against the apoptosis with a dose-dependent manner (≥50 ng/ml). Furthermore, a rat myocardial ischemia and reperfusion (I/R) model was established by TWEAK preconditioning through injecting the TWEAK into the scar and border after ischemia immediately induced by ligating the left anterior descending coronary artery for 50 min and followed by different reperfusion times. The heart function was significantly improved in TWEAK preconditioning rats compared with controls as well as the infarct size was significantly reduced 21 days after reperfusion. Meanwhile, TWEAK protected the cardiac apoptosis by activation of cardioprotective signaling PI3K/AKT during I/R. Our findings suggest that TWEAK may represent a cardioprotective factor that inhibits the myocyte death of myocardial IRI.
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Affiliation(s)
- Bin Yang
- Shanxi Medical UniversityTaiyuan, China
- The Cardiovascular Disease Hospital of Shanxi Medical UniversityTaiyuan, China
| | - Ping Yan
- Shanxi Medical UniversityTaiyuan, China
- The First Hospital of Shanxi Medical UniversityTaiyuan, China
| | - Hui Gong
- Shanxi Medical UniversityTaiyuan, China
| | - Lin Zuo
- Shanxi Medical UniversityTaiyuan, China
| | - Ying Shi
- Shanxi Medical UniversityTaiyuan, China
- The Second Hospital of Shanxi Medical UniversityTaiyuan, China
| | - Jian Guo
- Senboll Biotechnology Inc.Toronto, Ontario, Canada
| | - Rui Guo
- Shanxi Medical UniversityTaiyuan, China
| | - Jun Xie
- Shanxi Medical UniversityTaiyuan, China
| | - Bao Li
- Shanxi Medical UniversityTaiyuan, China
- The Cardiovascular Disease Hospital of Shanxi Medical UniversityTaiyuan, China
- The Second Hospital of Shanxi Medical UniversityTaiyuan, China
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16
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Huang M, Pan D, Du Y, Zhu H, Zhang L, Xu T, Luo Y, Li D. Na(+)/Ca(2+) exchanger 1 (NCX-1) mediates the anti-apoptotic effect of Akt1 in neonatal rat cardiomyocytes during ischemia/reperfusion. Am J Transl Res 2016; 8:1369-1378. [PMID: 27186265 PMCID: PMC4859625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 02/23/2016] [Indexed: 06/05/2023]
Abstract
The purpose of this study was to investigate the anti-apoptotic role of Akt1 gene in neonatal rat cardiomyocytes and the relationship with Na(+)/Ca(2+) exchanger 1 (NCX1) during ischemia/reperfusion (IR). The cultured original rat cardiomyocytes were randomly divided into five groups: normal control group (C group), hypoxia/reoxygenation group (HR group), the control vector pLVX-EGFP-3FLAG group (CV group), the gene pLVX-EGFP-3FLAG-Akt1 transfection group (A group), and Akt1 inhibitor LY294002 group (LY group). Cardiomyocyte vitality was determined using MTT, and the apoptosis was determined by TUNEL to verify the anti-apoptotic role of Akt1. The mRNA levels of Akt1 and NCX1 were determined by RT-PCR, the protein expression of Akt1, p-Akt1, NCX1 and the apoptotic proteins of mitochondrial pathway cytochrome C (Cyto C) and caspase-9 were measured by Western blot. As a result, transfected Akt1 (A group) showed increased myocardial cell viability and reduced apoptosis, with increase in Akt1 expression and decrease in NCX1 expression. The levels of apoptotic proteins Cyto C and caspase-9 also declined. This study demonstrated that lentivirus-mediated transfection of Akt1 played an anti-apoptotic role during IR of rat cardiomyocytes, via inhibition of NCX1 and other mitochondrial proteins.
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Affiliation(s)
- Manman Huang
- Institute of Cardiovascular Disease Research, Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Defeng Pan
- Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Yinping Du
- Institute of Cardiovascular Disease Research, Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Hong Zhu
- Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Lin Zhang
- Institute of Cardiovascular Disease Research, Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Tongda Xu
- Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Yuanyuan Luo
- Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
| | - Dongye Li
- Institute of Cardiovascular Disease Research, Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
- Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221002, Jiangsu, China
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17
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TAK1 Regulates Myocardial Response to Pathological Stress via NFAT, NFκB, and Bnip3 Pathways. Sci Rep 2015; 5:16626. [PMID: 26564789 PMCID: PMC4643217 DOI: 10.1038/srep16626] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 10/16/2015] [Indexed: 01/19/2023] Open
Abstract
TAK1 (TGFβ-activated kinase-1) signaling is essential in regulating a number of important biological functions, including innate immunity, inflammatory response, cell growth and differentiation, and myocardial homeostasis. The precise role of TAK1 in the adult heart under pathological conditions remains largely unknown. Importantly, we observed that TAK1 is upregulated during compensatory hypertrophy but downregulated in end-stage heart failure. Here we generated transgenic mice with inducible expression of an active TAK1 mutant (TAK1ΔN) in the adult heart. TAK1ΔN transgenic mice developed greater cardiac hypertrophy compared with control mice after transverse aortic constriction (TAC), which was largely blocked by ablation of calcineurin Aβ. Expression of TAK1ΔN also promoted NFAT (nuclear factor of activated T-cells) transcriptional activity in luciferase reporter mice at baseline, which was further enhanced after TAC. Our results revealed that activation of TAK1 promoted adaptive cardiac hypertrophy through a cross-talk between calcineurin-NFAT and IKK-NFκB pathways. More significantly, adult-onset inducible expression of TAK1ΔN protected the myocardium from adverse remodeling and heart failure after myocardial infarction or long-term pressure overload, by preventing cardiac cell death and fibrosis. Mechanistically, TAK1 exerts its cardioprotective effect through activation of NFAT/NFκB, downregulation of Bnip3, and inhibition of cardiac cell death.
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18
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Blázquez-Prieto J, López-Alonso I, Amado-Rodríguez L, Batalla-Solís E, González-López A, Albaiceta GM. Exposure to mechanical ventilation promotes tolerance to ventilator-induced lung injury by Ccl3 downregulation. Am J Physiol Lung Cell Mol Physiol 2015; 309:L847-56. [DOI: 10.1152/ajplung.00193.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/14/2015] [Indexed: 01/22/2023] Open
Abstract
Inflammation plays a key role in the development of ventilator-induced lung injury (VILI). Preconditioning with a previous exposure can damp the subsequent inflammatory response. Our objectives were to demonstrate that tolerance to VILI can be induced by previous low-pressure ventilation, and to identify the molecular mechanisms responsible for this phenomenon. Intact 8- to 12-wk-old male CD1 mice were preconditioned with 90 min of noninjurious ventilation [peak pressure 17 cmH2O, positive end-expiratory pressure (PEEP) 2 cmH2O] and extubated. Seven days later, preconditioned mice and intact controls were submitted to injurious ventilation (peak pressure 20 cmH2O, PEEP 0 cmH2O) for 2 h to induce VILI. Preconditioned mice showed lower histological lung injury scores, bronchoalveolar lavage albumin content, and lung neutrophilic infiltration after injurious ventilation, with no differences in Il6 or Il10 expression. Microarray analyses revealed a downregulation of Calcb, Hspa1b, and Ccl3, three genes related to tolerance phenomena, in preconditioned animals. Among the previously identified genes, only Ccl3, which encodes the macrophage inflammatory protein 1 alpha (MIP-1α), showed significant differences between intact and preconditioned mice after high-pressure ventilation. In separate, nonconditioned animals, treatment with BX471, a specific blocker of CCR1 (the main receptor for MIP-1α), decreased lung damage and neutrophilic infiltration caused by high-pressure ventilation. We conclude that previous exposure to noninjurious ventilation induces a state of tolerance to VILI. Downregulation of the chemokine gene Ccl3 could be the mechanism responsible for this effect.
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Affiliation(s)
- Jorge Blázquez-Prieto
- Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Inés López-Alonso
- Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Laura Amado-Rodríguez
- Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
- Área de Gestión Clínica de Medicina Intensiva, Hospital Valle del Nalón, Langreo, Spain
| | - Estefanía Batalla-Solís
- Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
| | - Adrián González-López
- Department of Anesthesiology and Operative Intensive Care Medicine, Charité Universitätsmedizin, Berlin, Germany; and
| | - Guillermo M. Albaiceta
- Departamento de Biología Funcional, Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Oviedo, Spain
- Servicio de Medicina Intensiva, Hospital Universitario Central de Asturias, Oviedo, Spain
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19
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Abstract
Myocardial infarction is defined as sudden ischemic death of myocardial tissue. In the clinical context, myocardial infarction is usually due to thrombotic occlusion of a coronary vessel caused by rupture of a vulnerable plaque. Ischemia induces profound metabolic and ionic perturbations in the affected myocardium and causes rapid depression of systolic function. Prolonged myocardial ischemia activates a "wavefront" of cardiomyocyte death that extends from the subendocardium to the subepicardium. Mitochondrial alterations are prominently involved in apoptosis and necrosis of cardiomyocytes in the infarcted heart. The adult mammalian heart has negligible regenerative capacity, thus the infarcted myocardium heals through formation of a scar. Infarct healing is dependent on an inflammatory cascade, triggered by alarmins released by dying cells. Clearance of dead cells and matrix debris by infiltrating phagocytes activates anti-inflammatory pathways leading to suppression of cytokine and chemokine signaling. Activation of the renin-angiotensin-aldosterone system and release of transforming growth factor-β induce conversion of fibroblasts into myofibroblasts, promoting deposition of extracellular matrix proteins. Infarct healing is intertwined with geometric remodeling of the chamber, characterized by dilation, hypertrophy of viable segments, and progressive dysfunction. This review manuscript describes the molecular signals and cellular effectors implicated in injury, repair, and remodeling of the infarcted heart, the mechanistic basis of the most common complications associated with myocardial infarction, and the pathophysiologic effects of established treatment strategies. Moreover, we discuss the implications of pathophysiological insights in design and implementation of new promising therapeutic approaches for patients with myocardial infarction.
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Affiliation(s)
- Nikolaos G Frangogiannis
- The Wilf Family Cardiovascular Research Institute, Division of Cardiology, Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, USA
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20
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Caspase-1 cleavage of transcription factor GATA4 and regulation of cardiac cell fate. Cell Death Dis 2014; 5:e1566. [PMID: 25501827 PMCID: PMC4649840 DOI: 10.1038/cddis.2014.524] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 10/23/2014] [Accepted: 10/28/2014] [Indexed: 11/26/2022]
Abstract
Caspase-1 or interleukin-1β (IL-1β) converting enzyme is a pro-inflammatory member of the caspase family. An IL-1β-independent role for caspase-1 in cardiomyocyte cell death and heart failure has emerged but the mechanisms underlying these effects are incompletely understood. Here, we report that transcription factor GATA4, a key regulator of cardiomyocyte survival and adaptive stress response is an in vivo and in vitro substrate for caspase-1. Caspase-1 mediated cleavage of GATA4 generates a truncated protein that retains the ability to bind DNA but lacks transcriptional activation domains and acts as a dominant negative regulator of GATA4. We show that caspase-1 is rapidly activated in cardiomyocyte nuclei treated with the cell death inducing drug Doxorubicin. We also find that inhibition of caspase-1 alone is as effective as complete caspase inhibition at rescuing GATA4 degradation and myocyte cell death. Caspase-1 inhibition of GATA4 transcriptional activity is rescued by HSP70, which binds directly to GATA4 and masks the caspase recognition motif. The data identify a caspase-1 nuclear substrate and suggest a direct role for caspase-1 in transcriptional regulation. This mechanism may underlie the inflammation-independent action of caspase-1 in other organs.
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21
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Javan H, Szucsik AM, Li L, Schaaf CL, Salama ME, Selzman CH. Cardiomyocyte p65 nuclear factor-κB is necessary for compensatory adaptation to pressure overload. Circ Heart Fail 2014; 8:109-18. [PMID: 25480781 DOI: 10.1161/circheartfailure.114.001297] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Nuclear factor κB (NF-κB) is often implicated in contributing to the detrimental effects of cardiac injury. This ostensibly negative view of NF-κB competes with its important role in the normal host inflammatory and immune response. We have previously demonstrated that pharmacological inhibition of NF-κB at the time of acute pressure overload accelerates the progression of left ventricular hypertrophy to heart failure in mice. NF-κB regulates angiogenesis and other factors responsible for compensatory reaction to intracellular hypoxia. We hypothesized that impaired angiogenesis may be the trigger, not the result, of pathological left ventricular hypertrophy through NF-κB-related pathways. METHODS AND RESULTS Transgenic mice were generated with cardiomyocyte-specific deletion of the p65 subunit of NF-κB. Mice underwent transverse aortic constriction and serially followed up with echocardiography for 6 weeks. Cardiomyocyte p65 NF-κB deletion promoted maladaptive left ventricular hypertrophy and accelerated progression toward heart failure as measured by ejection fraction, left ventricular mass, and lung congestion. Transgenic mice had higher levels of fibrosis and periostin expression. Whole-field digital microscopy revealed increased capillary domain areas in knockout mice while concurrently demonstrating decreased microvessel density. This observation was associated with decreased expression of hypoxia-inducible factor 1α. CONCLUSIONS Rather than developing compensatory left ventricular hypertrophy, pressure overload in cardiomyocyte NF-κB-deficient mice resulted in functional deterioration that was associated with increased fibrosis, decreased hypoxia-inducible factor expression, and decreased microvessel density. These observations mechanistically implicate NF-κB, and its regulation of hypoxic stress, as an important factor determining the path between adaptive hypertrophy and maladaptive heart failure.
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Affiliation(s)
- Hadi Javan
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City
| | - Amanda M Szucsik
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City
| | - Ling Li
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City
| | - Christin L Schaaf
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City
| | - Mohamed E Salama
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City
| | - Craig H Selzman
- From the Division of Cardiothoracic Surgery, Department of Surgery and Molecular Medicine (H.J., A.M.S., L.L., C.L.S., C.H.S.) and Department of Pathology, ARUP Institute for Research and Development (M.E.S.), University of Utah, Salt Lake City.
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22
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Yu L, Zhao Y, Xu S, Jin C, Wang M, Fu G. Leptin confers protection against TNF-α-induced apoptosis in rat cardiomyocytes. Biochem Biophys Res Commun 2014; 455:126-32. [DOI: 10.1016/j.bbrc.2014.10.134] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 10/27/2014] [Indexed: 12/29/2022]
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Song MA, Paradis AN, Gay MS, Shin J, Zhang L. Differential expression of microRNAs in ischemic heart disease. Drug Discov Today 2014; 20:223-35. [PMID: 25461956 DOI: 10.1016/j.drudis.2014.10.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/16/2014] [Accepted: 10/15/2014] [Indexed: 01/02/2023]
Abstract
Recent studies provide evidence that ischemic preconditioning (IP) and ischemia/reperfusion (IR) injury lead to altered expression of microRNAs (miRNAs) that affect the survival and recovery of cardiomyocytes. These endogenous ∼22-nucleotide noncoding RNAs negatively regulate gene expression via degradation and translational inhibition of their target mRNAs. miRNAs are involved in differentiation, proliferation, electrical conduction, angiogenesis and apoptosis. These pathways can lead to physiological and pathological adaptations. This review intends to explore several facets of miRNA expression and the underlying mechanisms involved in IR injury, as well as IP as a cardioprotective strategy. In addition, we will investigate miRNA interaction with the renin-angiotensin system and the potential use of miRNAs in developing sensitive biomarkers for cardiovascular disease.
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Affiliation(s)
- Minwoo A Song
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
| | - Alexandra N Paradis
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
| | - Maresha S Gay
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
| | - John Shin
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
| | - Lubo Zhang
- Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
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24
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Thomas CM, Yong QC, Rosa RM, Seqqat R, Gopal S, Casarini DE, Jones WK, Gupta S, Baker KM, Kumar R. Cardiac-specific suppression of NF-κB signaling prevents diabetic cardiomyopathy via inhibition of the renin-angiotensin system. Am J Physiol Heart Circ Physiol 2014; 307:H1036-45. [PMID: 25085967 DOI: 10.1152/ajpheart.00340.2014] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Activation of NF-κB signaling in the heart may be protective or deleterious depending on the pathological context. In diabetes, the role of NF-κB in cardiac dysfunction has been investigated using pharmacological approaches that have a limitation of being nonspecific. Furthermore, the specific cellular pathways by which NF-κB modulates heart function in diabetes have not been identified. To address these questions, we used a transgenic mouse line expressing mutated IκB-α in the heart (3M mice), which prevented activation of canonical NF-κB signaling. Diabetes was developed by streptozotocin injections in wild-type (WT) and 3M mice. Diabetic WT mice developed systolic and diastolic cardiac dysfunction by the 12th week, as measured by echocardiography. In contrast, cardiac function was preserved in 3M mice up to 24 wk of diabetes. Diabetes induced an elevation in cardiac oxidative stress in diabetic WT mice but not 3M mice compared with nondiabetic control mice. In diabetic WT mice, an increase in the phospholamban/sarco(endo)plasmic reticulum Ca(2+)-ATPase 2 ratio and decrease in ryanodine receptor expression were observed, whereas diabetic 3M mice showed an opposite effect on these parameters of Ca(2+) handling. Significantly, renin-angiotensin system activity was suppressed in diabetic 3M mice compared with an increase in WT animals. In conclusion, these results demonstrate that inhibition of NF-κB signaling in the heart prevents diabetes-induced cardiac dysfunction through preserved Ca(2+) handling and inhibition of the cardiac renin-angiotensin system.
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Affiliation(s)
- Candice M Thomas
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas
| | - Qian Chen Yong
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas
| | - Rodolfo M Rosa
- Nephrology Division, Department of Medicine, Federal University of Sao Paulo, Sao Paulo, Brazil; and
| | - Rachid Seqqat
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas
| | - Shanthi Gopal
- Central Texas Veterans Health Care System, Temple, Texas
| | - Dulce E Casarini
- Nephrology Division, Department of Medicine, Federal University of Sao Paulo, Sao Paulo, Brazil; and
| | - W Keith Jones
- Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois
| | - Sudhiranjan Gupta
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas
| | - Kenneth M Baker
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas
| | - Rajesh Kumar
- Division of Molecular Cardiology, Department of Medicine, Texas A&M Health Science Center, College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas; Central Texas Veterans Health Care System, Temple, Texas;
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25
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Dungan JR, Hauser ER, Qin X, Kraus WE. The genetic basis for survivorship in coronary artery disease. Front Genet 2013; 4:191. [PMID: 24143143 PMCID: PMC3784965 DOI: 10.3389/fgene.2013.00191] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Accepted: 09/06/2013] [Indexed: 01/14/2023] Open
Abstract
Survivorship is a trait characterized by endurance and virility in the face of hardship. It is largely considered a psychosocial attribute developed during fatal conditions, rather than a biological trait for robustness in the context of complex, age-dependent diseases like coronary artery disease (CAD). The purpose of this paper is to present the novel phenotype, survivorship in CAD as an observed survival advantage concurrent with clinically significant CAD. We present a model for characterizing survivorship in CAD and its relationships with overlapping time- and clinically-related phenotypes. We offer an optimal measurement interval for investigating survivorship in CAD. We hypothesize genetic contributions to this construct and review the literature for evidence of genetic contribution to overlapping phenotypes in support of our hypothesis. We also present preliminary evidence of genetic effects on survival in people with clinically significant CAD from a primary case-control study of symptomatic coronary disease. Identifying gene variants that confer improved survival in the context of clinically appreciable CAD may improve our understanding of cardioprotective mechanisms acting at the gene level and potentially impact patients clinically in the future. Further, characterizing other survival-variant genetic effects may improve signal-to-noise ratio in detecting gene associations for CAD.
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26
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Zhang XQ, Tang R, Li L, Szucsik A, Javan H, Saegusa N, Spitzer KW, Selzman CH. Cardiomyocyte-specific p65 NF-κB deletion protects the injured heart by preservation of calcium handling. Am J Physiol Heart Circ Physiol 2013; 305:H1089-97. [PMID: 23913709 DOI: 10.1152/ajpheart.00067.2013] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NF-κB is a well-known transcription factor that is intimately involved with inflammation and immunity. We have previously shown that NF-κB promotes inflammatory events and mediates adverse cardiac remodeling following ischemia reperfusion (I/R). Conversely, others have pointed to the beneficial influence of NF-κB in I/R injury related to its anti-apoptotic effects. Understanding the seemingly disparate influence of manipulating NF-κB is hindered, in part, by current approaches that only indirectly interfere with the function of its most transcriptionally active unit, p65 NF-κB. Mice were generated with cardiomyocyte-specific deletion of p65 NF-κB. Phenotypically, these mice and their hearts appeared normal. Basal and stimulated p65 expression were significantly reduced in whole hearts and completely ablated in isolated cardiomyocytes. When compared with wild-type mice, transgenic animals were protected from both global I/R by Langendorff as well as regional I/R by coronary ligation and release. The protected, transgenic hearts had less cytokine activity and decreased apoptosis. Furthermore, p65 ablation was associated with enhanced calcium reuptake by the sarcoplasmic reticulum. This influence on calcium handling was related to increased expression of phosphorylated phospholamban in conditional p65 null mice. In conclusion, cardiomyocyte-specific deletion of the most active, canonical NF-κB subunit affords cardioprotection to both global and regional I/R injury. The beneficial effects of NF-κB inhibition are related, in part, to modulation of intracellular calcium homeostasis.
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Affiliation(s)
- Xiu Q Zhang
- Division of Cardiothoracic Surgery, Department of Surgery, University of Utah, Salt Lake City, Utah
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27
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Eapen DJ, Manocha P, Patel RS, Hammadah M, Veledar E, Wassel C, Nanjundappa RA, Sikora S, Malayter D, Wilson PWF, Sperling L, Quyyumi AA, Epstein SE. Aggregate risk score based on markers of inflammation, cell stress, and coagulation is an independent predictor of adverse cardiovascular outcomes. J Am Coll Cardiol 2013; 62:329-37. [PMID: 23665099 DOI: 10.1016/j.jacc.2013.03.072] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 03/19/2013] [Accepted: 03/26/2013] [Indexed: 12/22/2022]
Abstract
OBJECTIVES This study sought to determine an aggregate, pathway-specific risk score for enhanced prediction of death and myocardial infarction (MI). BACKGROUND Activation of inflammatory, coagulation, and cellular stress pathways contribute to atherosclerotic plaque rupture. We hypothesized that an aggregate risk score comprised of biomarkers involved in these different pathways-high-sensitivity C-reactive protein (CRP), fibrin degradation products (FDP), and heat shock protein 70 (HSP70) levels-would be a powerful predictor of death and MI. METHODS Serum levels of CRP, FDP, and HSP70 were measured in 3,415 consecutive patients with suspected or confirmed coronary artery disease (CAD) undergoing cardiac catheterization. Survival analyses were performed with models adjusted for established risk factors. RESULTS Median follow-up was 2.3 years. Hazard ratios (HRs) for all-cause death and MI based on cutpoints were as follows: CRP ≥3.0 mg/l, HR: 1.61; HSP70 >0.625 ng/ml, HR; 2.26; and FDP ≥1.0 μg/ml, HR: 1.62 (p < 0.0001 for all). An aggregate biomarker score between 0 and 3 was calculated based on these cutpoints. Compared with the group with a 0 score, HRs for all-cause death and MI were 1.83, 3.46, and 4.99 for those with scores of 1, 2, and 3, respectively (p for each: <0.001). Annual event rates were 16.3% for the 4.2% of patients with a score of 3 compared with 2.4% in 36.4% of patients with a score of 0. The C statistic and net reclassification improved (p < 0.0001) with the addition of the biomarker score. CONCLUSIONS An aggregate score based on serum levels of CRP, FDP, and HSP70 is a predictor of future risk of death and MI in patients with suspected or known CAD.
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Affiliation(s)
- Danny J Eapen
- Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, GA 30322, USA
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Gupta A, Cooper ZA, Tulapurkar ME, Potla R, Maity T, Hasday JD, Singh IS. Toll-like receptor agonists and febrile range hyperthermia synergize to induce heat shock protein 70 expression and extracellular release. J Biol Chem 2012; 288:2756-66. [PMID: 23212905 DOI: 10.1074/jbc.m112.427336] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Heat shock protein (Hsp) 70 expression can be stimulated by febrile range temperature (FRT). Hsp70 has been shown to be elevated in serum of patients with sepsis, and when released from cells, extracellular Hsp70 exerts endotoxin-like effects through Toll-like receptor 4 (TLR4) receptors. Circulating TLR agonists and fever both persist for the first several days of sepsis, and each can activate Hsp70 expression; however, the effect of combined exposure to FRT and TLR agonists on Hsp70 expression is unknown. We found that concurrent exposure to FRT (39.5 °C) and agonists for TLR4 (LPS), TLR2 (Pam3Cys), or TLR3 (poly(IC)) synergized to increase Hsp70 expression and extracellular release in RAW264.7 macrophages. The increase in Hsp70 expression was associated with activation of p38 and ERK MAP kinases, phosphorylation of histone H3, and increased recruitment of HSF1 to the Hsp70 promoter. Pretreatment with the p38 MAPK inhibitor SB283580 but not the ERK pathway inhibitor UO126 significantly reduced Hsp70 gene modification and Hsp70 expression in RAW cells co-exposed to LPS and FRT. In mice challenged with intratracheal LPS and then exposed to febrile range hyperthermia (core temperature, ∼39.5 °C), Hsp70 levels in lung tissue and in cell-free lung lavage were increased compared with mice exposed to either hyperthermia or LPS alone. We propose a model of how enhanced Hsp70 expression and extracellular release in patients concurrently exposed to fever and TLR agonists may contribute to the pathogenesis of sepsis.
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Affiliation(s)
- Aditi Gupta
- Division of Pulmonary and Critical Care, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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Andersen NM, Tang R, Li L, Javan H, Zhang XQ, Selzman CH. Inhibitory kappa-B kinase-β inhibition prevents adaptive left ventricular hypertrophy. J Surg Res 2012; 178:105-9. [PMID: 22464396 DOI: 10.1016/j.jss.2012.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 02/28/2012] [Accepted: 03/01/2012] [Indexed: 01/13/2023]
Abstract
BACKGROUND Most cardiovascular studies have implicated the central transcription factor nuclear factor kappa-B (NF-κB) as contributing to the detrimental effects of cardiac injury. This ostensibly negative view of NF-κB competes with its important role in the normal host inflammatory and immune response. Pressure overload, left ventricular hypertrophy (LVH), and heart failure represent a spectrum of disease that has both adaptive and maladaptive components. In contrast to its known effects related to myocardial ischemia-reperfusion, we hypothesized that NF-κB is necessary for the compensatory phase of cardiac remodeling. METHODS C57BL6 mice underwent minimally invasive transverse aortic constriction with or without inhibition of the proximal NF-κB kinase, inhibitory kappa-B kinase-β. Isolated cardiomyocytes were cultured. Transthoracic echocardiography was performed on all mice. RESULTS Inhibitory kappa-B kinase-β inhibition successfully decreased cardiomyocyte expression of phosphorylated p65 NF-κB and decreased expression of hypertrophic markers with stimulation in vitro. Three weeks after transverse aortic constriction, the mice treated with inhibitory kappa-B kinase-β inhibition more aggressively developed LVH, as measured by heart weight/body weight ratio, left ventricular mass, and wall thickness. These mice also demonstrated a functional decline, as measured by decreased fractional shortening and ejection fraction. These findings were associated with decreased protein expression of p65 NF-κB. CONCLUSIONS Although short-term pressure-overload results in compensatory LVH with normal cardiac function, NF-κB inhibition resulted in increased LVH that was associated with functional deterioration. These observations suggest that NF-κB is an important part of the adaptive phase of LVH, and its inhibition detrimentally affects cardiac remodeling.
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Affiliation(s)
- Nancy M Andersen
- Department of Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Gally F, Minor MN, Smith SK, Case SR, Chu HW. Heat shock factor 1 protects against lung mycoplasma pneumoniae infection in mice. J Innate Immun 2011; 4:59-68. [PMID: 22042134 DOI: 10.1159/000333089] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 09/14/2011] [Indexed: 12/31/2022] Open
Abstract
Heat shock factor 1 (HSF1) is a transcriptional factor that controls the induction of heat shock proteins (e.g. HSP70) in response to stress. Bacterial infections contribute to the pathobiology of chronic lung diseases such as chronic obstructive pulmonary disease and asthma. Whether HSF1 is critical to lung bacterial infection remains unknown. This study is aimed at investigating the impact of HSF1 deficiency on lung Mycoplasma pneumoniae (Mp) infection and elucidating the underlying molecular mechanisms, such as Toll-like receptor 2 (TLR2) signaling. HSF1(-/-) and HSF1(+/+) mice were intranasally infected with Mp or saline and sacrificed 4, 24 and 72 h after treatment. HSF1(-/-) mice had a higher lung Mp load than HSF1(+/+) mice. Mp-induced lung TLR2, nuclear factor-κB and associated inflammation [e.g. keratinocyte-derived chemokine (KC), neutrophils and histopathology] were delayed in HSF1(-/-) mice as compared to HSF1(+/+) mice. HSP70 protein levels in bronchoalveolar lavage fluid of HSF1(-/-) mice were decreased. Furthermore, in response to Mp infection, HSF1(-/-) alveolar macrophages had less TLR2 mRNA expression and KC production than HSF1(+/+) counterparts. Nuclear factor-κB activity and KC production in HSF1(-/-) macrophages could be rescued by addition of exogenous HSP70 protein. These data suggest that HSF1 is necessary to initiate host defense against bacterial infection partly through promoting early TLR2 signaling activation.
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Affiliation(s)
- Fabienne Gally
- Department of Medicine, National Jewish Health, Denver, CO, USA
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Tranter M, Helsley RN, Paulding WR, McGuinness M, Brokamp C, Haar L, Liu Y, Ren X, Jones WK. Coordinated post-transcriptional regulation of Hsp70.3 gene expression by microRNA and alternative polyadenylation. J Biol Chem 2011; 286:29828-37. [PMID: 21757701 DOI: 10.1074/jbc.m111.221796] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Heat shock protein 70 (Hsp70) is well documented to possess general cytoprotective properties in protecting the cell against stressful and noxious stimuli. We have recently shown that expression of the stress-inducible Hsp70.3 gene in the myocardium in response to ischemic preconditioning is NF-κB-dependent and necessary for the resulting late phase cardioprotection against a subsequent ischemia/reperfusion injury. Here we show that the Hsp70.3 gene product is subject to post-transcriptional regulation through parallel regulatory processes involving microRNAs and alternative polyadenylation of the mRNA transcript. First, we show that cardiac ischemic preconditioning of the in vivo mouse heart results in decreased levels of two Hsp70.3-targeting microRNAs: miR-378* and miR-711. Furthermore, an ischemic or heat shock stimulus induces alternative polyadenylation of the expressed Hsp70.3 transcript that results in the accumulation of transcripts with a shortened 3'-UTR. This shortening of the 3'-UTR results in the loss of the binding site for the suppressive miR-378* and thus renders the alternatively polyadenylated transcript insusceptible to miR-378*-mediated suppression. Results also suggest that the alternative polyadenylation-mediated shortening of the Hsp70.3 3'-UTR relieves translational suppression observed in the long 3'-UTR variant, allowing for a more robust increase in protein expression. These results demonstrate alternative polyadenylation of Hsp70.3 in parallel with ischemic or heat shock-induced up-regulation of mRNA levels and implicate the importance of this process in post-transcriptional control of Hsp70.3 expression.
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Affiliation(s)
- Michael Tranter
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA
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