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Skryabin EB, De Jong KA, Subramanian H, Bork NI, Froese A, Skryabin BV, Nikolaev VO. CRISPR/Cas9 Knock-Out in Primary Neonatal and Adult Cardiomyocytes Reveals Distinct cAMP Dynamics Regulation by Various PDE2A and PDE3A Isoforms. Cells 2023; 12:1543. [PMID: 37296663 PMCID: PMC10253201 DOI: 10.3390/cells12111543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/15/2023] [Accepted: 06/02/2023] [Indexed: 06/12/2023] Open
Abstract
Cyclic nucleotide phosphodiesterases 2A (PDE2A) and PDE3A play an important role in the regulation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP)-to-cAMP crosstalk. Each of these PDEs has up to three distinct isoforms. However, their specific contributions to cAMP dynamics are difficult to explore because it has been challenging to generate isoform-specific knock-out mice or cells using conventional methods. Here, we studied whether the CRISPR/Cas9 approach for precise genome editing can be used to knock out Pde2a and Pde3a genes and their distinct isoforms using adenoviral gene transfer in neonatal and adult rat cardiomyocytes. Cas9 and several specific gRNA constructs were cloned and introduced into adenoviral vectors. Primary adult and neonatal rat ventricular cardiomyocytes were transduced with different amounts of Cas9 adenovirus in combination with PDE2A or PDE3A gRNA constructs and cultured for up to 6 (adult) or 14 (neonatal) days to analyze PDE expression and live cell cAMP dynamics. A decline in mRNA expression for PDE2A (~80%) and PDE3A (~45%) was detected as soon as 3 days post transduction, with both PDEs being reduced at the protein level by >50-60% in neonatal cardiomyocytes (after 14 days) and >95% in adult cardiomyocytes (after 6 days). This correlated with the abrogated effects of selective PDE inhibitors in the live cell imaging experiments based on using cAMP biosensor measurements. Reverse transcription PCR analysis revealed that only the PDE2A2 isoform was expressed in neonatal myocytes, while adult cardiomyocytes expressed all three PDE2A isoforms (A1, A2, and A3) which contributed to the regulation of cAMP dynamics as detected by live cell imaging. In conclusion, CRISPR/Cas9 is an effective tool for the in vitro knock-out of PDEs and their specific isoforms in primary somatic cells. This novel approach suggests distinct regulation of live cell cAMP dynamics by various PDE2A and PDE3A isoforms in neonatal vs. adult cardiomyocytes.
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Affiliation(s)
- Egor B. Skryabin
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
| | - Kirstie A. De Jong
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
- German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Hariharan Subramanian
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
- German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Nadja I. Bork
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
- German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Alexander Froese
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
- German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Boris V. Skryabin
- Core Facility Transgenic Animal and Genetic Engineering Models (TRAM), University of Münster, 48149 Münster, Germany;
| | - Viacheslav O. Nikolaev
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (E.B.S.); (K.A.D.J.); (H.S.); (N.I.B.); (A.F.)
- German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
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Glen C, Tan YY, Waterston A, Evans TRJ, Jones RJ, Petrie MC, Lang NN. Mechanistic and Clinical Overview Cardiovascular Toxicity of BRAF and MEK Inhibitors: JACC: CardioOncology State-of-the-Art Review. JACC CardioOncol 2022; 4:1-18. [PMID: 35492830 PMCID: PMC9040125 DOI: 10.1016/j.jaccao.2022.01.096] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/07/2022] [Indexed: 02/07/2023] Open
Abstract
Rapidly accelerated fibrosarcoma B-type (BRAF) and mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors have revolutionized melanoma treatment. Approximately half of patients with melanoma harbor a BRAF gene mutation with subsequent dysregulation of the RAF-MEK-ERK signaling pathway. Targeting this pathway with BRAF and MEK blockade results in control of cell proliferation and, in most cases, disease control. These pathways also have cardioprotective effects and are necessary for normal vascular and cardiac physiology. BRAF and MEK inhibitors are associated with adverse cardiovascular effects including hypertension, left ventricular dysfunction, venous thromboembolism, atrial arrhythmia, and electrocardiographic QT interval prolongation. These effects may be underestimated in clinical trials. Baseline cardiovascular assessment and follow-up, including serial imaging and blood pressure assessment, are essential to balance optimal anti-cancer therapy while minimizing cardiovascular side effects. In this review, an overview of BRAF/MEK inhibitor-induced cardiovascular toxicity, the mechanisms underlying these, and strategies for surveillance, prevention, and treatment of these effects are provided.
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Key Words
- ACE, angiotensin-converting enzyme
- AF, atrial fibrillation
- BRAF inhibitor
- BRAF, rapidly accelerated fibrosarcoma B-type
- CVAE, cardiovascular adverse event
- EGFR, epidermal growth factor receptor
- ERK, extracellular signal-regulated kinase
- LVSD, left ventricular systolic dysfunction
- MEK inhibitor
- MEK, mitogen-activated extracellular signal-regulated kinase
- RAF, rapidly accelerated fibrosarcoma
- VEGF, vascular endothelial growth factor
- cardio-oncology
- cardiovascular toxicity
- hypertension
- left ventricular systolic dysfunction
- melanoma
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Affiliation(s)
- Claire Glen
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Yun Yi Tan
- Beatson West of Scotland Cancer Centre, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Ashita Waterston
- Beatson West of Scotland Cancer Centre, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Thomas R. Jeffry Evans
- Beatson West of Scotland Cancer Centre, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
- Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Robert J. Jones
- Beatson West of Scotland Cancer Centre, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
- Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Mark C. Petrie
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ninian N. Lang
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
- Beatson West of Scotland Cancer Centre, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
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3
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Zhao L, Ma Z, Guo Z, Zheng M, Li K, Yang X. Analysis of long non-coding RNA and mRNA profiles in epicardial adipose tissue of patients with atrial fibrillation. Biomed Pharmacother 2019; 121:109634. [PMID: 31731197 DOI: 10.1016/j.biopha.2019.109634] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 10/26/2019] [Accepted: 11/01/2019] [Indexed: 12/12/2022] Open
Abstract
Accumulating studies have suggested that epicardial adipose tissue (EAT) play an important role in the pathogenesis of atrial fibrillation (AF), but few have characterized the underlying mechanism between their interactions. Recent evidence suggested that bioactive molecules secreted from EAT, including exosomes carrying long non-coding RNAs (lncRNAs), may modulate atrial remodeling. LncRNAs are associated with cardiovascular disorders, including AF, but their roles in EAT remain elusive. The aim of the present study was to investigate the expression profile of lncRNAs in EAT with AF. Differentially expressed lncRNAs and nearby mRNAs interaction networks were constructed. Epicardial adipose samples were collected from patients with persistent non-valvular AF (n = 6) and sinus rhythm (SR) (n = 6), and the expression of lncRNAs and mRNAs were profiled using RNA-sequencing method. A total of 46,577 transcripts, including 35,552 protein-coding pattern, corresponding to 15,404 genes in EAT, among which, 655 mRNAs (265 upregulated and 390 downregulated) and 57 lncRNAs (17 upregulated and 40 downregulated) were differentially expressed between AF and SR (P < 0.05; fold change>1.5). GO enrichment, KEGG pathway analysis and interaction network construction showed that these differentially expressed lncRNAs were enriched in functional categories, including metabolism and stress response, which might contribute to the pathogenesis of AF. Our study demonstrated a differentially expressed lncRNA profile in EAT with AF, and provide a novel insight into the interactions between EAT and AF.
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Affiliation(s)
- Lei Zhao
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Zheng Ma
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Zongsheng Guo
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Meili Zheng
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Kuibao Li
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
| | - Xinchun Yang
- Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
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Bronte E, Bronte G, Novo G, Rinaldi G, Bronte F, Passiglia F, Russo A. Cardiotoxicity mechanisms of the combination of BRAF-inhibitors and MEK-inhibitors. Pharmacol Ther 2018; 192:65-73. [PMID: 29964124 DOI: 10.1016/j.pharmthera.2018.06.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Many new drugs have appeared in last years in the oncological treatment scenario. Each drug carries an important set of adverse events, not less, cardiovascular adverse events. This aspect is even more important considering the increasing use of combination therapies with two drugs, or three drugs as in some ongoing clinical trials. Besides it represents a growing problem for Cardiologists, that face it in every day clinical practice and that will face it probably more and more in the coming years. This work reviews the mechanism of action of BRAF-inhibitors and MEK-inhibitors used together, the pathophysiological mechanisms that lead to cardiovascular toxicity. Particularly, it focuses on hypertension and ejection fraction reduction development. Then, it follows the examination of published data for each combination therapy. A Literature research was carried out using Pubmed selecting review articles, original studies and clinical trials, but mainly focusing on phase 3 studies. This work aims to summarize the knowledge about BRAF-inhibitor and MEK-inhibitor treatment and its cardiovascular toxicity to make it usable and give the basic tools to Cardiologists and Oncologists for a better management of cancer patient undergoing this treatment. Besides a deeper knowledge of the cardiovascular adverse events linked to this treatment and the magnitude of their expression and frequency can lead to a targeted cardiological treatment.
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Affiliation(s)
- Enrico Bronte
- Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy.
| | - Giuseppe Bronte
- Department of Medical Oncology, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy
| | - Giuseppina Novo
- Division of Cardiology, Department of Internal Medicine and Specialties, University of Palermo, Palermo, Italy
| | - Gaetana Rinaldi
- Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy
| | - Fabrizio Bronte
- U.O.C. di Gastroenterologia, Ospedali Riuniti Villa Sofia-Cervello, Palermo, Italy
| | - Francesco Passiglia
- Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy
| | - Antonio Russo
- Department of Surgical, Oncological and Oral Sciences, Section of Medical Oncology, University of Palermo, Palermo, Italy
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5
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Ren L, Wu C, Yang K, Chen S, Ye P, Wu J, Zhang A, Huang X, Wang K, Deng P, Ding X, Chen M, Xia J. A Disintegrin and Metalloprotease-22 Attenuates Hypertrophic Remodeling in Mice Through Inhibition of the Protein Kinase B Signaling Pathway. J Am Heart Assoc 2018; 7:JAHA.117.005696. [PMID: 29358191 PMCID: PMC5850139 DOI: 10.1161/jaha.117.005696] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Severe cardiac hypertrophy can lead to cardiac remodeling and even heart failure in the end, which is a leading cause of cardiovascular disease-related mortality worldwide. A disintegrin and metalloprotease-22 (ADAM22), a member of the transmembrane and secreted metalloendopeptidase family, participates in many biological processes, including those in the cardiovascular system. However, there is no explicit information on whether ADAM22 can regulate the process of cardiac hypertrophy; the effects that ADAM22 exerts in cardiac hypertrophy remain elusive. METHODS AND RESULTS We observed significantly increased ADAM22 expression in failing hearts from patients with dilated cardiomyopathy and hypertrophic cardiomyopathy; the same trend was observed in mice induced by transaortic constriction and in neonatal rat cardiomyocytes treated by angiotensin II. Therefore, we constructed both cardiac-specific ADAM22 overexpression and knockout mice. At 4 weeks after transaortic constriction, cardiac-specific ADAM22 knockout, by the CRISPR/Cas9 (clustered regularly interspaced palindromic repeat (CRISPR)-Cas9) system, deteriorated the severity of cardiac hypertrophy in mice, whereas cardiac-specific ADAM22 overexpression mitigated the degrees of cardiac hypertrophy in mice. Similarly, altered ADAM22 expression modulated the angiotensin II-mediated cardiomyocyte hypertrophy in neonatal rat cardiomyocytes. After screening several signaling pathways, we found ADAM22 played a role in inhibition of protein kinase B (AKT) activation. Under the cardiac-specific ADAM22 knockout background, AKT activation was enhanced in transaortic constriction-induced mice and angiotensin II-stimulated neonatal rat cardiomyocytes, with a severe degree of cardiac hypertrophy. Treatment of a specific AKT inhibitor attenuated the transaortic constriction-enhanced AKT activation and cardiac hypertrophy in mice. CONCLUSIONS The findings demonstrated that ADAM22 negatively regulates the AKT activation and the process of cardiac hypertrophy and may provide new insights into the pathobiological features of cardiac hypertrophy.
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Affiliation(s)
- Lingyun Ren
- Department of Anesthesiology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chuangyan Wu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kai Yang
- Department of Cardiology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shanshan Chen
- Key Laboratory for Molecular Diagnosis of Hubei Province, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ping Ye
- Department of Cardiology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jie Wu
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Anchen Zhang
- Department of Cardiology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaofan Huang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ke Wang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peng Deng
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiangchao Ding
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Manhua Chen
- Department of Cardiology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiahong Xia
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Francois AA, Obasanjo-Blackshire K, Clark JE, Boguslavskyi A, Holt MR, Parker PJ, Marber MS, Heads RJ. Loss of Protein Kinase Novel 1 (PKN1) is associated with mild systolic and diastolic contractile dysfunction, increased phospholamban Thr17 phosphorylation, and exacerbated ischaemia-reperfusion injury. Cardiovasc Res 2018; 114:138-157. [PMID: 29045568 PMCID: PMC5815577 DOI: 10.1093/cvr/cvx206] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 03/17/2017] [Accepted: 10/13/2017] [Indexed: 01/20/2023] Open
Abstract
Aims PKN1 is a stress-responsive protein kinase acting downstream of small GTP-binding proteins of the Rho/Rac family. The aim was to determine its role in endogenous cardioprotection. Methods and results Hearts from PKN1 knockout (KO) or wild type (WT) littermate control mice were perfused in Langendorff mode and subjected to global ischaemia and reperfusion (I/R). Myocardial infarct size was doubled in PKN1 KO hearts compared to WT hearts. PKN1 was basally phosphorylated on the activation loop Thr778 PDK1 target site which was unchanged during I/R. However, phosphorylation of p42/p44-MAPK was decreased in KO hearts at baseline and during I/R. In cultured neonatal rat ventricular cardiomyocytes (NRVM) and NRVM transduced with kinase dead (KD) PKN1 K644R mutant subjected to simulated ischaemia/reperfusion (sI/R), PhosTag® gel analysis showed net dephosphorylation of PKN1 during sI and early R despite Thr778 phosphorylation. siRNA knockdown of PKN1 in NRVM significantly decreased cell survival and increased cell injury by sI/R which was reversed by WT- or KD-PKN1 expression. Confocal immunofluorescence analysis of PKN1 in NRVM showed increased localization to the sarcoplasmic reticulum (SR) during sI. GC-MS/MS and immunoblot analysis of PKN1 immunoprecipitates following sI/R confirmed interaction with CamKIIδ. Co-translocation of PKN1 and CamKIIδ to the SR/membrane fraction during sI correlated with phospholamban (PLB) Thr17 phosphorylation. siRNA knockdown of PKN1 in NRVM resulted in increased basal CamKIIδ activation and increased PLB Thr17 phosphorylation only during sI. In vivo PLB Thr17 phosphorylation, Sarco-Endoplasmic Reticulum Ca2+ ATPase (SERCA2) expression and Junctophilin-2 (Jph2) expression were also basally increased in PKN1 KO hearts. Furthermore, in vivo P-V loop analysis of the beat-to-beat relationship between rate of LV pressure development or relaxation and end diastolic P (EDP) showed mild but significant systolic and diastolic dysfunction with preserved ejection fraction in PKN1 KO hearts. Conclusion Loss of PKN1 in vivo significantly reduces endogenous cardioprotection and increases myocardial infarct size following I/R injury. Cardioprotection by PKN1 is associated with reduced CamKIIδ-dependent PLB Thr17 phosphorylation at the SR and therefore may stabilize the coupling of SR Ca2+ handling and contractile function, independent of its kinase activity.
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Affiliation(s)
- Asvi A Francois
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Kofo Obasanjo-Blackshire
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - James E Clark
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Andrii Boguslavskyi
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Mark R Holt
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
| | - Peter J Parker
- Division of Cancer Studies, School of Cancer and Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
- Protein Phosphorylation Laboratory, Francis Crick Institute, Lincoln’s Inn Fields, London, UK
| | - Michael S Marber
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Richard J Heads
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
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Martínez-Martínez E, Ibarrola J, Fernández-Celis A, Santamaria E, Fernández-Irigoyen J, Rossignol P, Jaisser F, López-Andrés N. Differential Proteomics Identifies Reticulocalbin-3 as a Novel Negative Mediator of Collagen Production in Human Cardiac Fibroblasts. Sci Rep 2017; 7:12192. [PMID: 28939891 PMCID: PMC5610303 DOI: 10.1038/s41598-017-12305-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/06/2017] [Indexed: 01/18/2023] Open
Abstract
Cardiac fibrosis is characterized by an excessive accumulation of extracellular matrix components, including collagens. Galectin-3 (Gal-3) and Cardiotrophin-1 (CT-1) are two profibrotic molecules that mediate Aldosterone (Aldo)-induced cardiac fibrosis. However the underlying mechanisms are not well defined. Our aim is to characterize changes in the proteome of human cardiac fibroblasts treated with Aldo, Gal-3 or CT-1 to identify new common proteins that might be new therapeutic targets in cardiac fibrosis. Using a quantitative proteomic approach in human cardiac fibroblasts, our results show that Aldo, Gal-3 and CT-1 modified the expression of 30, 17 and 89 proteins respectively, being common the reticulocalbin (RCN) family members. RCN-3 down-regulation triggered by Aldo, Gal-3 and CT-1 was verified. Treatment with recombinant RCN-3 decreased collagens expression in human cardiac fibroblasts through Akt phosphorylation. Interestingly, CRISPR/Cas9-mediated activation of RCN-3 decreased collagen production in human cardiac fibroblasts. In addition, recombinant RCN-3 blocked the profibrotic effects of Aldo, Gal-3 and CT-1. Interestingly, RCN-3 blunted the increase in collagens expression induced by other profibrotic stimuli, angiotensin II, in human cardiac fibroblasts. Our results suggest that RCN-3 emerges as a new potential negative regulator of collagen production and could represent a therapeutic target in the context of cardiac fibrosis.
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Affiliation(s)
- Ernesto Martínez-Martínez
- Cardiovascular Translational Research. Navarrabiomed (Fundación Miguel Servet), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain.,INSERM UMRS 1138 Team 1, Centre de Recherche des Cordeliers, University Pierre and Marie Curie, Paris, France
| | - Jaime Ibarrola
- Cardiovascular Translational Research. Navarrabiomed (Fundación Miguel Servet), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
| | - Amaya Fernández-Celis
- Cardiovascular Translational Research. Navarrabiomed (Fundación Miguel Servet), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
| | - Enrique Santamaria
- Proteored-ISCIII, Proteomics Unit, Navarrabiomed, Departamento de Salud, Universidad Pública de Navarra, IDISNA, Navarra Institute for Health Research, Pamplona, Spain
| | - Joaquín Fernández-Irigoyen
- Proteored-ISCIII, Proteomics Unit, Navarrabiomed, Departamento de Salud, Universidad Pública de Navarra, IDISNA, Navarra Institute for Health Research, Pamplona, Spain
| | - Patrick Rossignol
- INSERM, Centre d'Investigations Cliniques- Plurithématique 1433, UMR 1116 Université de Lorraine, CHRU de Nancy, FCRIN INI-CRCT, France
| | - Frederic Jaisser
- INSERM UMRS 1138 Team 1, Centre de Recherche des Cordeliers, University Pierre and Marie Curie, Paris, France.,INSERM, Centre d'Investigations Cliniques- Plurithématique 1433, UMR 1116 Université de Lorraine, CHRU de Nancy, FCRIN INI-CRCT, France
| | - Natalia López-Andrés
- Cardiovascular Translational Research. Navarrabiomed (Fundación Miguel Servet), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain. .,INSERM, Centre d'Investigations Cliniques- Plurithématique 1433, UMR 1116 Université de Lorraine, CHRU de Nancy, FCRIN INI-CRCT, France.
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8
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Huang Y, Guo XX, Han B, Zhang XM, An S, Zhang XY, Yang Y, Liu Y, Hao Q, Xu TR. Decoding the full picture of Raf1 function based on its interacting proteins. Oncotarget 2017; 8:68329-68337. [PMID: 28978120 PMCID: PMC5620260 DOI: 10.18632/oncotarget.19353] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 06/18/2017] [Indexed: 01/10/2023] Open
Abstract
Raf1 is a member of the Raf kinase family and regulates many fundamental cell processes, including proliferation, differentiation, apoptosis, motility, and metabolism. However, the functions of Raf1 have not been completely elucidated. To better understand Raf1 function, we investigated the proteins that interacted with Raf1. We identified 198 Raf1 interacting proteins and our data suggested that Raf1 may regulate cell processes through these interactions. These interaction partners were involved in all ten hallmarks of cancer, suggesting that Raf1 is involved in different aspects of carcinogenesis. In addition, we showed that Raf1 interacting proteins were enriched in six signaling pathways and many human diseases. The interaction partners identified in this study may represent oncological candidates for future investigations into Raf1 function. Our findings have provided an overview of Raf1 function from a systems biology perspective.
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Affiliation(s)
- Ying Huang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China.,Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, China
| | - Xiao-Xi Guo
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Bing Han
- Institute of Biomedical Sciences, Minhang Hospital, Fudan University, Shanghai, China
| | - Xu-Min Zhang
- State Key Laboratory of Genetic Engineering, Department of Biochemistry, School of Life Sciences, Fudan University, Shanghai, China
| | - Su An
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Xin-Yu Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Yang Yang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Ying Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Qian Hao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Tian-Rui Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
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9
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Li X, Augustine A, Sun D, Li L, Fliegel L. Activation of the Na +/H + exchanger in isolated cardiomyocytes through β-Raf dependent pathways. Role of Thr 653 of the cytosolic tail. J Mol Cell Cardiol 2016; 99:65-75. [PMID: 27555478 DOI: 10.1016/j.yjmcc.2016.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 08/04/2016] [Accepted: 08/19/2016] [Indexed: 10/21/2022]
Abstract
The mammalian Na+/H+ exchanger isoform 1 (NHE1) is a ubiquitous plasma membrane protein that is a key regulator of intracellular pH in isolated cardiomyocytes. A 500 amino acid membrane domain removes protons and is regulated by a 315 amino acid cytosolic domain. In the myocardium, aberrant regulation of NHE1 contributes to ischemia reperfusion damage and to heart hypertrophy. We examined mechanisms of regulation of NHE1 in the myocardium by endothelin and β-Raf. Endothelin stimulated NHE1 activity and activated Erk-dependent pathways. Inhibition of β-Raf reduced NHE1 activity and Erk-pathway activation. We demonstrated that myocardial β-Raf binds to the C-terminal 182 amino acids of the NHE1 protein and that β-Raf is associated with NHE1 in intact cardiomyocytes. NHE1 was phosphorylated in vivo and the protein kinase inhibitor sorafenib reduced NHE1 phosphorylation levels. Immunoprecipitates of β-Raf from cardiomyocytes phosphorylated the C-terminal 182 amino acids of NHE1 and mass spectrometry analysis showed that amino acid Thr653 was phosphorylated. Mutation of this amino acid to Ala resulted in defective activity while mutation to Asp restored the activity. The results demonstrate that Thr653 is an important regulatory amino acid of NHE1 that is activated through β-Raf dependent pathways by phosphorylation either directly or indirectly by β-Raf, and this affects NHE1 activity.
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Affiliation(s)
- Xiuju Li
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Aruna Augustine
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Difei Sun
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
| | - Liang Li
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
| | - Larry Fliegel
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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10
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Suppressor of IKKɛ is an essential negative regulator of pathological cardiac hypertrophy. Nat Commun 2016; 7:11432. [PMID: 27249321 PMCID: PMC4895691 DOI: 10.1038/ncomms11432] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 03/23/2016] [Indexed: 12/22/2022] Open
Abstract
Although pathological cardiac hypertrophy represents a leading cause of morbidity and mortality worldwide, our understanding of the molecular mechanisms underlying this disease is still poor. Here, we demonstrate that suppressor of IKKɛ (SIKE), a negative regulator of the interferon pathway, attenuates pathological cardiac hypertrophy in rodents and non-human primates in a TANK-binding kinase 1 (TBK1)/AKT-dependent manner. Sike-deficient mice develop cardiac hypertrophy and heart failure, whereas Sike-overexpressing transgenic (Sike-TG) mice are protected from hypertrophic stimuli. Mechanistically, SIKE directly interacts with TBK1 to inhibit the TBK1-AKT signalling pathway, thereby achieving its anti-hypertrophic action. The suppression of cardiac remodelling by SIKE is further validated in rats and monkeys. Collectively, these findings identify SIKE as a negative regulator of cardiac remodelling in multiple animal species due to its inhibitory regulation of the TBK1/AKT axis, suggesting that SIKE may represent a therapeutic target for the treatment of cardiac hypertrophy and heart failure. Identifying pathways that cause pathological cardiac hypertrophy holds great therapeutic potential. Here the authors discover one such pathway and show that SIKE, an inhibitor of interferon signalling, prevents pathological but not physiological cardiac hypertrophy by interacting with TBK1 and modulating the TBK1/AKT signalling in rodents and monkeys.
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11
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He B, Zhao YC, Gao LC, Ying XY, Xu LW, Su YY, Ji QQ, Lin N, Pu J. Ubiquitin-Specific Protease 4 Is an Endogenous Negative Regulator of Pathological Cardiac Hypertrophy. Hypertension 2016; 67:1237-48. [PMID: 27045030 DOI: 10.1161/hypertensionaha.116.07392] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 03/08/2016] [Indexed: 11/16/2022]
Abstract
Dysregulation of the ubiquitin proteasome system components ubiquitin ligases and proteasome plays an important role in the pathogenesis of cardiac hypertrophy. However, little is known about the role of another ubiquitin proteasome system component, the deubiquitinating enzymes, in cardiac hypertrophy. Here, we revealed a crucial role of ubiquitin specific protease 4 (USP4), a deubiquitinating enzyme prominently expressed in the heart, in attenuating pathological cardiac hypertrophy and dysfunction. USP4 levels were consistently decreased in human failing hearts and in murine hypertrophied hearts. Adenovirus-mediated gain- and loss-of-function approaches indicated that deficiency of endogenous USP4 promoted myocyte hypertrophy induced by angiotensin II in vitro, whereas restoration of USP4 significantly attenuated the prohypertrophic effect of angiotensin II. To corroborate the role of USP4 in vivo, we generated USP4 global knockout mice and mice with cardiac-specific overexpression of USP4. Consistent with the in vitro study, USP4 depletion exacerbated the hypertrophic phenotype and cardiac dysfunction in mice subjected to pressure overload, whereas USP4 transgenic mice presented ameliorated pathological cardiac hypertrophy compared with their control littermates. Molecular analysis revealed that USP4 deficiency augmented the activation of the transforming growth factor β–activated kinase 1 (TAK1)-(JNK1/2)/P38 signaling in response to hypertrophic stress, and blockage of TAK1 activation abolished the pathological effects of USP4 deficiency in vivo. These findings provide the first evidence for the involvement of USP4 in cardiac hypertrophy, and shed light on the therapeutic potential of targeting USP4 in the treatment of cardiac hypertrophy.
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Affiliation(s)
- Ben He
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yi-Chao Zhao
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ling-Chen Gao
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Xiao-Ying Ying
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Long-Wei Xu
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yuan-Yuan Su
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qing-Qi Ji
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Nan Lin
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jun Pu
- From the Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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12
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Huang J, Chen L, Yao Y, Tang C, Ding J, Fu C, Li H, Ma G. Pivotal Role of Regulator of G-protein Signaling 12 in Pathological Cardiac Hypertrophy. Hypertension 2016; 67:1228-36. [PMID: 27091895 DOI: 10.1161/hypertensionaha.115.06877] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 03/19/2016] [Indexed: 11/16/2022]
Abstract
Cardiac hypertrophy is a major predictor of heart failure and is regulated by diverse signaling pathways. As a typical multi-domain member of the regulator of G-protein signaling (RGS) family, RGS12 plays a regulatory role in various signaling pathways. However, the precise effect of RGS12 on cardiac hypertrophy remains largely unknown. In this study, we observed increased expression of RGS12 in the development of pathological cardiac hypertrophy and heart failure. We then generated genetically engineered mice and neonatal rat cardiomyocytes to investigate the effects of RGS12 during this pathological process. Four weeks after aortic banding, RGS12-deficient hearts showed decreased cardiomyocyte cross area (374.7±43.2 μm(2) versus 487.1±47.9 μm(2) in controls; P<0.05) with preserved fractional shortening (43.0±3.4% versus 28.4±2.2% in controls; P<0.05), whereas RGS12-overexpressing hearts exhibited increased cardiomyocyte cross area (582.4±46.7 μm(2) versus 474.8±40.0 μm(2) in controls; P<0.05) and reduced fractional shortening (20.8±4.1% versus 28.6±3.2% in controls; P<0.05). RGS12 also contributed to angiotensin II-induced hypertrophy in isolated cardiomyocytes. Mechanistically, our data indicated that the activation of MEK1/2-ERK1/2 signaling may be responsible for the prohypertrophic action of RGS12. In addition, the requirement of the MEK1/2-ERK1/2 signaling for RGS12-mediated cardiac hypertrophy was confirmed in rescue experiments using the MEK1/2-specific inhibitor U0126. In conclusion, our findings provide a novel diagnostic and therapeutic target for pathological cardiac hypertrophy and heart failure.
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Affiliation(s)
- Jia Huang
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Lijuan Chen
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Yuyu Yao
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Chengchun Tang
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Jiandong Ding
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Cong Fu
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Hongliang Li
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.)
| | - Genshan Ma
- From the Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, PR China (J.H., L.C., Y.Y., C.T., J.D., C.F., G.M.); Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, PR China (H.L.); and Cardiovascular Research Institute of Wuhan University, Wuhan, PR China (H.L.).
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13
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Stoppel WL, Kaplan DL, Black LD. Electrical and mechanical stimulation of cardiac cells and tissue constructs. Adv Drug Deliv Rev 2016; 96:135-55. [PMID: 26232525 DOI: 10.1016/j.addr.2015.07.009] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/16/2015] [Accepted: 07/25/2015] [Indexed: 12/19/2022]
Abstract
The field of cardiac tissue engineering has made significant strides over the last few decades, highlighted by the development of human cell derived constructs that have shown increasing functional maturity over time, particularly using bioreactor systems to stimulate the constructs. However, the functionality of these tissues is still unable to match that of native cardiac tissue and many of the stem-cell derived cardiomyocytes display an immature, fetal like phenotype. In this review, we seek to elucidate the biological underpinnings of both mechanical and electrical signaling, as identified via studies related to cardiac development and those related to an evaluation of cardiac disease progression. Next, we review the different types of bioreactors developed to individually deliver electrical and mechanical stimulation to cardiomyocytes in vitro in both two and three-dimensional tissue platforms. Reactors and culture conditions that promote functional cardiomyogenesis in vitro are also highlighted. We then cover the more recent work in the development of bioreactors that combine electrical and mechanical stimulation in order to mimic the complex signaling environment present in vivo. We conclude by offering our impressions on the important next steps for physiologically relevant mechanical and electrical stimulation of cardiac cells and engineered tissue in vitro.
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14
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Ding Y, Caberoy NB, Guo F, LeBlanc ME, Zhang C, Wang W, Wang F, Chen R, Li W. Reticulocalbin-1 facilitates microglial phagocytosis. PLoS One 2015; 10:e0126993. [PMID: 25992960 PMCID: PMC4436338 DOI: 10.1371/journal.pone.0126993] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 04/09/2015] [Indexed: 12/26/2022] Open
Abstract
Phagocytosis is critical to the clearance of apoptotic cells, cellular debris and deleterious metabolic products for tissue homeostasis. Phagocytosis ligands directly recognizing deleterious cargos are the key to defining the functional roles of phagocytes, but are traditionally identified on a case-by-case basis with technical challenges. As a result, extrinsic regulation of phagocytosis is poorly defined. Here we demonstrate that microglial phagocytosis ligands can be systematically identified by a new approach of functional screening. One of the identified ligands is reticulocalbin-1 (Rcn1), which was originally reported as a Ca2+-binding protein with a strict expression in the endoplasmic reticulum. Our results showed that Rcn1 can be secreted from healthy cells and that secreted Rcn1 selectively bound to the surface of apoptotic neurons, but not healthy neurons. Independent characterization revealed that Rcn1 stimulated microglial phagocytosis of apoptotic but not healthy neurons. Ingested apoptotic cells were targeted to phagosomes and co-localized with phagosome marker Rab7. These data suggest that Rcn1 is a genuine phagocytosis ligand. The new approach described in this study will enable systematic identification of microglial phagocytosis ligands with broad applicability to many other phagocytes.
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Affiliation(s)
- Ying Ding
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
| | - Nora B. Caberoy
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, 89154, United States of America
| | - Feiye Guo
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
| | - Michelle E. LeBlanc
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
| | - Chenming Zhang
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
- Jinan 2 People’s Hospital, Jinan, 250001, China
| | - Weiwen Wang
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
| | - Feng Wang
- Dept. of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX, 77030, United States of America
| | - Rui Chen
- Dept. of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX, 77030, United States of America
| | - Wei Li
- Bascom Palmer Eye Institute, Dept. of Ophthalmology, University of Miami School of Medicine, Miami, FL, 33136, United States of America
- Neuroscience Program, University of Miami School of Medicine, Miami, FL, 33136, United States of America
- * E-mail:
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