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Hilgendorf I, Frantz S, Frangogiannis NG. Repair of the Infarcted Heart: Cellular Effectors, Molecular Mechanisms and Therapeutic Opportunities. Circ Res 2024; 134:1718-1751. [PMID: 38843294 PMCID: PMC11164543 DOI: 10.1161/circresaha.124.323658] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Accepted: 05/08/2024] [Indexed: 06/12/2024]
Abstract
The adult mammalian heart has limited endogenous regenerative capacity and heals through the activation of inflammatory and fibrogenic cascades that ultimately result in the formation of a scar. After infarction, massive cardiomyocyte death releases a broad range of damage-associated molecular patterns that initiate both myocardial and systemic inflammatory responses. TLRs (toll-like receptors) and NLRs (NOD-like receptors) recognize damage-associated molecular patterns (DAMPs) and transduce downstream proinflammatory signals, leading to upregulation of cytokines (such as interleukin-1, TNF-α [tumor necrosis factor-α], and interleukin-6) and chemokines (such as CCL2 [CC chemokine ligand 2]) and recruitment of neutrophils, monocytes, and lymphocytes. Expansion and diversification of cardiac macrophages in the infarcted heart play a major role in the clearance of the infarct from dead cells and the subsequent stimulation of reparative pathways. Efferocytosis triggers the induction and release of anti-inflammatory mediators that restrain the inflammatory reaction and set the stage for the activation of reparative fibroblasts and vascular cells. Growth factor-mediated pathways, neurohumoral cascades, and matricellular proteins deposited in the provisional matrix stimulate fibroblast activation and proliferation and myofibroblast conversion. Deposition of a well-organized collagen-based extracellular matrix network protects the heart from catastrophic rupture and attenuates ventricular dilation. Scar maturation requires stimulation of endogenous signals that inhibit fibroblast activity and prevent excessive fibrosis. Moreover, in the mature scar, infarct neovessels acquire a mural cell coat that contributes to the stabilization of the microvascular network. Excessive, prolonged, or dysregulated inflammatory or fibrogenic cascades accentuate adverse remodeling and dysfunction. Moreover, inflammatory leukocytes and fibroblasts can contribute to arrhythmogenesis. Inflammatory and fibrogenic pathways may be promising therapeutic targets to attenuate heart failure progression and inhibit arrhythmia generation in patients surviving myocardial infarction.
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Affiliation(s)
- Ingo Hilgendorf
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen and Faculty of Medicine at the University of Freiburg, Freiburg, Germany
| | - Stefan Frantz
- Medizinische Klinik und Poliklinik I, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Nikolaos G Frangogiannis
- The Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology), Albert Einstein College of Medicine, Bronx NY
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2
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Liu X, Yang M, Li J, Liu H, Dong Y, Zheng J, Huang Y. Identification of CFH and FHL2 as biomarkers for idiopathic pulmonary fibrosis. Front Med (Lausanne) 2024; 11:1363643. [PMID: 38784225 PMCID: PMC11111937 DOI: 10.3389/fmed.2024.1363643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Background Idiopathic pulmonary fibrosis (IPF) is a fatal disease of unknown etiology with a poor prognosis, characterized by a lack of effective diagnostic and therapeutic interventions. The role of immunity in the pathogenesis of IPF is significant, yet remains inadequately understood. This study aimed to identify potential key genes in IPF and their relationship with immune cells by integrated bioinformatics analysis and verify by in vivo and in vitro experiments. Methods Gene microarray data were obtained from the Gene Expression Omnibus (GEO) for differential expression analysis. The differentially expressed genes (DEGs) were identified and subjected to functional enrichment analysis. By utilizing a combination of three machine learning algorithms, specific genes associated with idiopathic pulmonary fibrosis (IPF) were pinpointed. Then their diagnostic significance and potential co-regulators were elucidated. We further analyzed the correlation between key genes and immune infiltrating cells via single-sample gene set enrichment analysis (ssGSEA). Subsequently, a single-cell RNA sequencing data (scRNA-seq) was used to explore which cell types expressed key genes in IPF samples. Finally, a series of in vivo and in vitro experiments were conducted to validate the expression of candidate genes by western blot (WB), quantitative real-time PCR (qRT-PCR), and immunohistochemistry (IHC) analysis. Results A total of 647 DEGs of IPF were identified based on two datasets, including 225 downregulated genes and 422 upregulated genes. They are closely related to biological functions such as cell migration, structural organization, immune cell chemotaxis, and extracellular matrix. CFH and FHL2 were identified as key genes with diagnostic accuracy for IPF by three machine learning algorithms. Analysis using ssGSEA revealed a significant association of both CFH and FHL2 with diverse immune cells, such as B cells and NK cells. Further scRNA-seq analysis indicated CFH and FHL2 were specifically upregulated in human IPF tissues, which was confirmed by in vitro and in vivo experiments. Conclusion In this study, CFH and FHL2 have been identified as novel potential biomarkers for IPF, with potential diagnostic utility in future clinical applications. Subsequent investigations into the functions of these genes in IPF and their interactions with immune cells may enhance comprehension of the disease's pathogenesis and facilitate the identification of therapeutic targets.
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Affiliation(s)
- Xingchen Liu
- Department of Pathology, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Meng Yang
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Jiayu Li
- Department of Breast and Thyroid Surgery, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Hangxu Liu
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Yuchao Dong
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Jianming Zheng
- Department of Pathology, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
| | - Yi Huang
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Naval Medical University, Navy Medical University, Shanghai, China
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Torimoto K, Elliott K, Nakayama Y, Yanagisawa H, Eguchi S. Cardiac and perivascular myofibroblasts, matrifibrocytes, and immune fibrocytes in hypertension; commonalities and differences with other cardiovascular diseases. Cardiovasc Res 2024; 120:567-580. [PMID: 38395029 DOI: 10.1093/cvr/cvae044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 02/02/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024] Open
Abstract
Hypertension is a major cause of cardiovascular diseases such as myocardial infarction and stroke. Cardiovascular fibrosis occurs with hypertension and contributes to vascular resistance, aortic stiffness, and cardiac hypertrophy. However, the molecular mechanisms leading to fibroblast activation in hypertension remain largely unknown. There are two types of fibrosis: replacement fibrosis and reactive fibrosis. Replacement fibrosis occurs in response to the loss of viable tissue to form a scar. Reactive fibrosis occurs in response to an increase in mechanical and neurohormonal stress. Although both types of fibrosis are considered adaptive processes, they become maladaptive when the tissue loss is too large, or the stress persists. Myofibroblasts represent a subpopulation of activated fibroblasts that have gained contractile function to promote wound healing. Therefore, myofibroblasts are a critical cell type that promotes replacement fibrosis. Although myofibroblasts were recognized as the fibroblasts participating in reactive fibrosis, recent experimental evidence indicated there are distinct fibroblast populations in cardiovascular reactive fibrosis. Accordingly, we will discuss the updated definition of fibroblast subpopulations, the regulatory mechanisms, and their potential roles in cardiovascular pathophysiology utilizing new knowledge from various lineage tracing and single-cell RNA sequencing studies. Among the fibroblast subpopulations, we will highlight the novel roles of matrifibrocytes and immune fibrocytes in cardiovascular fibrosis including experimental models of hypertension, pressure overload, myocardial infarction, atherosclerosis, aortic aneurysm, and nephrosclerosis. Exploration into the molecular mechanisms involved in the differentiation and activation of those fibroblast subpopulations may lead to novel treatments for end-organ damage associated with hypertension and other cardiovascular diseases.
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Affiliation(s)
- Keiichi Torimoto
- Department of Cardiovascular Science, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Katherine Elliott
- Department of Cardiovascular Science, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Yuki Nakayama
- Department of Cardiovascular Science, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
| | - Hiromi Yanagisawa
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Japan
- Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Satoru Eguchi
- Department of Cardiovascular Science, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
- Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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Smolgovsky S, Theall B, Wagner N, Alcaide P. Fibroblasts and immune cells: at the crossroad of organ inflammation and fibrosis. Am J Physiol Heart Circ Physiol 2024; 326:H303-H316. [PMID: 38038714 PMCID: PMC11219060 DOI: 10.1152/ajpheart.00545.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/13/2023] [Accepted: 11/27/2023] [Indexed: 12/02/2023]
Abstract
The immune and fibrotic responses have evolved to work in tandem to respond to pathogen clearance and promote tissue repair. However, excessive immune and fibrotic responses lead to chronic inflammation and fibrosis, respectively, both of which are key pathological drivers of organ pathophysiology. Fibroblasts and immune cells are central to these responses, and evidence of these two cell types communicating through soluble mediators or adopting functions from each other through direct contact is constantly emerging. Here, we review complex junctions of fibroblast-immune cell cross talk, such as immune cell modulation of fibroblast physiology and fibroblast acquisition of immune cell-like functions, as well as how these systems of communication contribute to organ pathophysiology. We review the concept of antigen presentation by fibroblasts among different organs with different regenerative capacities, and then focus on the inflammation-fibrosis axis in the heart in the complex syndrome of heart failure. We discuss the need to develop anti-inflammatory and antifibrotic therapies, so far unsuccessful to date, that target novel mechanisms that sit at the crossroads of the fibrotic and immune responses.
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Affiliation(s)
- Sasha Smolgovsky
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States
- Immunology Graduate Program, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, United States
| | - Brandon Theall
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States
- Immunology Graduate Program, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, United States
| | - Noah Wagner
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States
| | - Pilar Alcaide
- Department of Immunology, Tufts University School of Medicine, Boston, Massachusetts, United States
- Immunology Graduate Program, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, United States
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Nelson AR, Christiansen SL, Naegle KM, Saucerman JJ. Logic-based mechanistic machine learning on high-content images reveals how drugs differentially regulate cardiac fibroblasts. Proc Natl Acad Sci U S A 2024; 121:e2303513121. [PMID: 38266046 PMCID: PMC10835125 DOI: 10.1073/pnas.2303513121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 11/30/2023] [Indexed: 01/26/2024] Open
Abstract
Fibroblasts are essential regulators of extracellular matrix deposition following cardiac injury. These cells exhibit highly plastic responses in phenotype during fibrosis in response to environmental stimuli. Here, we test whether and how candidate anti-fibrotic drugs differentially regulate measures of cardiac fibroblast phenotype, which may help identify treatments for cardiac fibrosis. We conducted a high-content microscopy screen of human cardiac fibroblasts treated with 13 clinically relevant drugs in the context of TGFβ and/or IL-1β, measuring phenotype across 137 single-cell features. We used the phenotypic data from our high-content imaging to train a logic-based mechanistic machine learning model (LogiMML) for fibroblast signaling. The model predicted how pirfenidone and Src inhibitor WH-4-023 reduce actin filament assembly and actin-myosin stress fiber formation, respectively. Validating the LogiMML model prediction that PI3K partially mediates the effects of Src inhibition, we found that PI3K inhibition reduces actin-myosin stress fiber formation and procollagen I production in human cardiac fibroblasts. In this study, we establish a modeling approach combining the strengths of logic-based network models and regularized regression models. We apply this approach to predict mechanisms that mediate the differential effects of drugs on fibroblasts, revealing Src inhibition acting via PI3K as a potential therapy for cardiac fibrosis.
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Affiliation(s)
- Anders R. Nelson
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, VA22903
| | - Steven L. Christiansen
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, VA22903
- Department of Biochemistry, Brigham Young University, Provo, UT84602
| | - Kristen M. Naegle
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, VA22903
| | - Jeffrey J. Saucerman
- Department of Biomedical Engineering, University of Virginia School of Medicine, Charlottesville, VA22903
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6
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Nelson AR, Christiansen SL, Naegle KM, Saucerman JJ. Logic-based mechanistic machine learning on high-content images reveals how drugs differentially regulate cardiac fibroblasts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.01.530599. [PMID: 36909540 PMCID: PMC10002757 DOI: 10.1101/2023.03.01.530599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Fibroblasts are essential regulators of extracellular matrix deposition following cardiac injury. These cells exhibit highly plastic responses in phenotype during fibrosis in response to environmental stimuli. Here, we test whether and how candidate anti-fibrotic drugs differentially regulate measures of cardiac fibroblast phenotype, which may help identify treatments for cardiac fibrosis. We conducted a high content microscopy screen of human cardiac fibroblasts treated with 13 clinically relevant drugs in the context of TGFβ and/or IL-1β, measuring phenotype across 137 single-cell features. We used the phenotypic data from our high content imaging to train a logic-based mechanistic machine learning model (LogiMML) for fibroblast signaling. The model predicted how pirfenidone and Src inhibitor WH-4-023 reduce actin filament assembly and actin-myosin stress fiber formation, respectively. Validating the LogiMML model prediction that PI3K partially mediates the effects of Src inhibition, we found that PI3K inhibition reduces actin-myosin stress fiber formation and procollagen I production in human cardiac fibroblasts. In this study, we establish a modeling approach combining the strengths of logic-based network models and regularized regression models, apply this approach to predict mechanisms that mediate the differential effects of drugs on fibroblasts, revealing Src inhibition acting via PI3K as a potential therapy for cardiac fibrosis.
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Affiliation(s)
- Anders R. Nelson
- University of Virginia School of Medicine, Charlottesville, VA 22903
| | - Steven L. Christiansen
- University of Virginia School of Medicine, Charlottesville, VA 22903
- Brigham Young University Department of Biochemistry, Provo, UT 84602
| | - Kristen M. Naegle
- University of Virginia School of Medicine, Charlottesville, VA 22903
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Garvin AM, Katwa LC. Primary cardiac fibroblast cell culture: methodological considerations for physiologically relevant conditions. Am J Physiol Heart Circ Physiol 2023; 325:H869-H881. [PMID: 37624100 DOI: 10.1152/ajpheart.00224.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/31/2023] [Accepted: 08/17/2023] [Indexed: 08/26/2023]
Abstract
Primary cardiac fibroblast (CF) tissue culture is a necessary tool for interrogating specific signaling mechanisms that dictate the phenotypic heterogeneity observed in vivo in different disease states. Traditional approaches that use tissue culture plastic and nutrient-rich medium have been shown to induce CF activation and, therefore, alter CF subpopulation composition. This shift away from in vivo phenotypes complicate the interpretation of results through the lens of the animal model. As the field works to identify CF diversity, these methodological flaws have begun to be addressed and more studies are focused on the dynamic interaction of CFs with their environment. This review focuses on the aspects of tissue culture that impact CF activation and, therefore, require consideration when designing in vitro experiments. The complexity of CF biology overlaid onto diverse model systems highlight the need for study-specific optimization and validation.
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Affiliation(s)
- Alexandra M Garvin
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States
| | - Laxmansa C Katwa
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, United States
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8
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Angelini A, Trial J, Saltzman AB, Malovannaya A, Cieslik KA. A defective mechanosensing pathway affects fibroblast-to-myofibroblast transition in the old male mouse heart. iScience 2023; 26:107283. [PMID: 37520701 PMCID: PMC10372839 DOI: 10.1016/j.isci.2023.107283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 05/12/2023] [Accepted: 06/30/2023] [Indexed: 08/01/2023] Open
Abstract
The cardiac fibroblast interacts with an extracellular matrix (ECM), enabling myofibroblast maturation via a process called mechanosensing. Although in the aging male heart, ECM is stiffer than in the young mouse, myofibroblast development is impaired, as demonstrated in 2-D and 3-D experiments. In old male cardiac fibroblasts, we found a decrease in actin polymerization, α-smooth muscle actin (α-SMA), and Kindlin-2 expressions, the latter an effector of the mechanosensing. When Kindlin-2 levels were manipulated via siRNA interference, young fibroblasts developed an old-like fibroblast phenotype, whereas Kindlin-2 overexpression in old fibroblasts reversed the defective phenotype. Finally, inhibition of overactivated extracellular regulated kinases 1 and 2 (ERK1/2) in the old male fibroblasts rescued actin polymerization and α-SMA expression. Pathological ERK1/2 overactivation was also attenuated by Kindlin-2 overexpression. In contrast, old female cardiac fibroblasts retained an operant mechanosensing pathway. In conclusion, we identified defective components of the Kindlin/ERK/actin/α-SMA mechanosensing axis in aged male fibroblasts.
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Affiliation(s)
- Aude Angelini
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - JoAnn Trial
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Alexander B. Saltzman
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX, USA
| | - Anna Malovannaya
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Mass Spectrometry Proteomics Core, Baylor College of Medicine, Houston, TX, USA
| | - Katarzyna A. Cieslik
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, TX, USA
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Liu Q, Li C, Deng B, Gao P, Wang L, Li Y, Shiri M, Alkaifi F, Zhao J, Stephens JM, Simintiras CA, Francis J, Sun J, Fu X. Tcf21 marks visceral adipose mesenchymal progenitors and functions as a rate-limiting factor during visceral adipose tissue development. Cell Rep 2023; 42:112166. [PMID: 36857185 PMCID: PMC10208561 DOI: 10.1016/j.celrep.2023.112166] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 01/01/2023] [Accepted: 02/09/2023] [Indexed: 03/02/2023] Open
Abstract
Distinct locations of different white adipose depots suggest anatomy-specific developmental regulation, a relatively understudied concept. Here, we report a population of Tcf21 lineage cells (Tcf21 LCs) present exclusively in visceral adipose tissue (VAT) that dynamically contributes to VAT development and expansion. During development, the Tcf21 lineage gives rise to adipocytes. In adult mice, Tcf21 LCs transform into a fibrotic or quiescent state. Multiomics analyses show consistent gene expression and chromatin accessibility changes in Tcf21 LC, based on which we constructed a gene-regulatory network governing Tcf21 LC activities. Furthermore, single-cell RNA sequencing (scRNA-seq) identifies the heterogeneity of Tcf21 LCs. Loss of Tcf21 promotes the adipogenesis and developmental progress of Tcf21 LCs, leading to improved metabolic health in the context of diet-induced obesity. Mechanistic studies show that the inhibitory effect of Tcf21 on adipogenesis is at least partially mediated via Dlk1 expression accentuation.
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Affiliation(s)
- Qianglin Liu
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA
| | - Chaoyang Li
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA
| | - Buhao Deng
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA; Department of Animal Sciences, Shanxi Agricultural University, Taigu, Shanxi, China
| | - Peidong Gao
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA
| | - Leshan Wang
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA
| | - Yuxia Li
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA
| | - Mohammad Shiri
- Department of Computer Science, Old Dominion University, Norfolk, VA, USA
| | - Fozi Alkaifi
- Department of Computer Science, Old Dominion University, Norfolk, VA, USA
| | - Junxing Zhao
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA; Department of Animal Sciences, Shanxi Agricultural University, Taigu, Shanxi, China
| | - Jacqueline M Stephens
- Pennington Biomedical Research Center, Baton Rouge, LA, USA; Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | | | - Joseph Francis
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - Jiangwen Sun
- Department of Computer Science, Old Dominion University, Norfolk, VA, USA.
| | - Xing Fu
- School of Animal Sciences, AgCenter, Louisiana State University, Baton Rouge, LA, USA.
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