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Hosoi T, Ino S, Ohnishi F, Todoroki K, Yoshii M, Kakimoto M, Müller CE, Ozawa K. Mechanisms of the action of adenine on anti-allergic effects in mast cells. IMMUNITY INFLAMMATION AND DISEASE 2017; 6:97-105. [PMID: 29094492 PMCID: PMC5818451 DOI: 10.1002/iid3.200] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 12/19/2022]
Abstract
Introduction Mast cells play an important role in allergic responses. Methods We herein demonstrated the mechanisms of inhibitory effect of adenine on IgE/antigen‐induced degranulation and TNF‐α release in mast cells. Results We found that these effects were dependent on the amino group of adenine because purine only weakly inhibited degranulation. Adenine also inhibited Ca2+ ionophore‐ and thapsigargin‐induced degranulation, however, this inhibitory effect was weaker than that of the antigen. Therefore, the inhibitory effects of adenine on degranulation may be mediated before as well as after the Ca2+ raise under the antigen stimulus. Adenine inhibited antigen‐induced Syk and the subsequent induction of AKT and ERK activation under FcϵRI‐mediated signal. Adenine also attenuated antigen‐induced increase in Ca2+. Furthermore, adenine inhibited IgE/antigen‐induced IKKα/β activation, which is involved in degranulation. Finally, adenine protected mice against anaphylactic allergic responses in vivo. Conclusions The present study revealed a key role of adenine in the attenuation of allergic responses through the inhibition of Syk‐mediated signal transduction and IKK‐mediated degranulation.
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Affiliation(s)
- Toru Hosoi
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Shinsuke Ino
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Fumie Ohnishi
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kenichi Todoroki
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Michiko Yoshii
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Mai Kakimoto
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Christa E Müller
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
| | - Koichiro Ozawa
- Department of Pharmacotherapy, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
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Fukuda T, Majumder K, Zhang H, Matsui T, Mine Y. Adenine has an anti-inflammatory effect through the activation of adenine receptor signaling in mouse macrophage. J Funct Foods 2017. [DOI: 10.1016/j.jff.2016.11.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Adenine attenuates the Ca(2+) contraction-signaling pathway via adenine receptor-mediated signaling in rat vascular smooth muscle cells. Naunyn Schmiedebergs Arch Pharmacol 2016; 389:999-1007. [PMID: 27318925 DOI: 10.1007/s00210-016-1264-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 06/08/2016] [Indexed: 10/21/2022]
Abstract
Our previous study demonstrated that adenine (6-amino-6H-purine) relaxed contracted rat aorta rings in an endothelial-independent manner. Although adenine receptors (AdeRs) are expressed in diverse tissues, aortic AdeR expression has not been ascertained. Thus, the aims of this study were to clarify the expression of AdeR in rat vascular smooth muscle cells (VSMCs) and to investigate the adenine-induced vasorelaxation mechanism(s). VSMCs were isolated from 8-week-old male Wistar-Kyoto rats and used in this study. Phosphorylation of myosin light chain (p-MLC) was measured by western blot. AdeR mRNA was detected by RT-PCR. Intracellular Ca(2+) concentration ([Ca(2+)]i) was measured by using Fura-2/AM. Vasorelaxant adenine (10-100 μM) significantly reduced p-MLC by angiotensin II (Ang II, 10 μM) in VSMCs (P < 0.05). We confirmed the expression of aortic AdeR mRNA and the activation of PKA in VSMCs through stimulation of AdeR by adenine by ELISA. Intracellular Ca(2+) concentration ([Ca(2+)]i) measurement demonstrated that adenine inhibits Ang II- and m-3M3FBS (PLC agonist)-induced [Ca(2+)]i elevation. In AdeR-knockdown VSMCs, PKA activation and p-MLC reduction by adenine were completely abolished. These results firstly demonstrated that vasorelaxant adenine can suppress Ca(2+) contraction signaling pathways via aortic AdeR/PKA activation in VSMCs.
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Fukuda T, Majumder K, Zhang H, Turner PV, Matsui T, Mine Y. Adenine Inhibits TNF-α Signaling in Intestinal Epithelial Cells and Reduces Mucosal Inflammation in a Dextran Sodium Sulfate-Induced Colitis Mouse Model. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:4227-4234. [PMID: 27166765 DOI: 10.1021/acs.jafc.6b00665] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Adenine (6-amino-6H-purine), found in molokheiya (Corchorus olitorius L.), has exerted vasorelaxation effects in the thoracic aorta. However, the mode of action of the anti-inflammatory effect of adenine is unclear. Thus, we investigated to clarify the effect of adenine on chronic inflammation of the gastrointestinal tract. In intestinal epithelial cells, adenine significantly inhibited tumor necrosis factor-α-induced interleukin-8 secretion. The inhibition of adenine was abolished under the treatment of inhibitors of adenyl cyclase (AC) and protein kinase A (PKA), indicating the effect of adenine was mediated through the AC/PKA pathway. Adenine (5, 10, and 50 mg/kg BW/day) was administered orally for 14 days to female BALB/c mice, and then 5% dextran sodium sulfate (DSS) was given to induce colitis. Adenine (5 mg/kg BW/day) significantly prevented DSS-induced colon shortening, expression of pro-inflammatory cytokines, and histological damage in the colon. These results suggest that adenine can be a promising nutraceutical for the prevention of intestinal inflammation.
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Affiliation(s)
- Toshihiko Fukuda
- Division of Bioresources and Bioenvironmental Sciences, Faculty of Agriculture, Graduate School, Kyushu University , Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | | | | | | | - Toshiro Matsui
- Division of Bioresources and Bioenvironmental Sciences, Faculty of Agriculture, Graduate School, Kyushu University , Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
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Thimm D, Schiedel AC, Peti-Peterdi J, Kishore BK, Müller CE. The nucleobase adenine as a signalling molecule in the kidney. Acta Physiol (Oxf) 2015; 213:808-18. [PMID: 25627062 DOI: 10.1111/apha.12452] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 12/07/2014] [Accepted: 01/05/2015] [Indexed: 11/30/2022]
Abstract
In 2002, the first receptor activated by the nucleobase adenine was discovered in rats. In the past years, two adenine receptors (AdeRs) in mice and one in Chinese hamsters, all of which belong to the family of G protein-coupled receptors (GPCRs), were cloned and pharmacologically characterized. Based on the nomenclature for other purinergic receptor families (P1 for adenosine receptors and P2 for nucleotide, e.g. ATP, receptors), AdeRs were designated P0 receptors. Pharmacological data indicate the existence of G protein-coupled AdeRs in pigs and humans as well; however, those have not been cloned so far. Current data suggest a role for adenine and AdeRs in renal proximal tubules. Furthermore, AdeRs are suggested to be functional counterplayers of vasopressin in the collecting duct system, thus exerting diuretic effects. We are only at the beginning of understanding the significance of this new class of purinergic receptors, which might become future drug targets.
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Affiliation(s)
- D. Thimm
- PharmaCenter Bonn; Pharmaceutical Institute, Pharmaceutical Chemistry I; University of Bonn; Bonn Germany
| | - A. C. Schiedel
- PharmaCenter Bonn; Pharmaceutical Institute, Pharmaceutical Chemistry I; University of Bonn; Bonn Germany
| | - J. Peti-Peterdi
- Department of Physiology and Biophysics; Zilkha Neurogenetic Institute; University of Southern California; Los Angeles CA USA
- Department of Medicine; Zilkha Neurogenetic Institute; University of Southern California; Los Angeles CA USA
| | - B. K. Kishore
- Nephrology Research; Department of Veterans Affairs Salt Lake City Health Care System; Salt Lake City UT USA
- Department of Internal Medicine; University of Utah Health Sciences Center; Salt Lake City UT USA
- Center on Aging; University of Utah Health Sciences Center; Salt Lake City UT USA
| | - C. E. Müller
- PharmaCenter Bonn; Pharmaceutical Institute, Pharmaceutical Chemistry I; University of Bonn; Bonn Germany
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Knospe M, Müller CE, Rosa P, Abdelrahman A, von Kügelgen I, Thimm D, Schiedel AC. The rat adenine receptor: pharmacological characterization and mutagenesis studies to investigate its putative ligand binding site. Purinergic Signal 2013; 9:367-81. [PMID: 23413038 PMCID: PMC3757150 DOI: 10.1007/s11302-013-9355-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 01/23/2013] [Indexed: 12/20/2022] Open
Abstract
The rat adenine receptor (rAdeR) was the first member of a family of G protein-coupled receptors (GPCRs) activated by adenine and designated as P0-purine receptors. The present study aimed at gaining insights into structural aspects of ligand binding and function of the rAdeR. We exchanged amino acid residues predicted to be involved in ligand binding (Phe110(3.24), Asn115(3.29), Asn173(4.60), Phe179(45.39), Asn194(5.40), Phe195(5.41), Leu201(5.47), His252(6.54), and Tyr268(7.32)) for alanine and expressed them in Spodoptera frugiperda (Sf9) insect cells. Membrane preparations subjected to [(3)H]adenine binding studies revealed only minor effects indicating that none of the exchanged amino acids is part of the ligand binding pocket, at least in the inactive state of the receptor. Furthermore, we coexpressed the rAdeR and its mutants with mammalian Gi proteins in Sf9 insect cells to probe receptor activation. Two amino acid residues, Asn194(5.40) and Leu201(5.47), were found to be crucial for activation since their alanine mutants did not respond to adenine. Moreover we showed that-in contrast to most other rhodopsin-like GPCRs-the rAdeR does not contain essential disulfide bonds since preincubation with dithiothreitol neither altered adenine binding in Sf9 cell membranes, nor adenine-induced inhibition of adenylate cyclase in 1321N1 astrocytoma cells transfected with the rAdeR. To detect rAdeRs by Western blot analysis, we developed a specific antibody. Finally, we were able to show that the extended N-terminal sequence of the rAdeR constitutes a putative signal peptide of unknown function that is cleaved off in the mature receptor. Our results provide important insights into this new, poorly investigated family of purinergic receptors.
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Affiliation(s)
- Melanie Knospe
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Christa E. Müller
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Patrizia Rosa
- />CNR—Institute of Neuroscience and Department of Medical Biotechnologies and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Aliaa Abdelrahman
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Ivar von Kügelgen
- />PharmaCenter Bonn, Department of Pharmacology, University of Bonn, Sigmund-Freud-Straße 25, 53127 Bonn, Germany
| | - Dominik Thimm
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Anke C. Schiedel
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
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Thimm D, Knospe M, Abdelrahman A, Moutinho M, Alsdorf BBA, von Kügelgen I, Schiedel AC, Müller CE. Characterization of new G protein-coupled adenine receptors in mouse and hamster. Purinergic Signal 2013; 9:415-26. [PMID: 23608776 PMCID: PMC3757137 DOI: 10.1007/s11302-013-9360-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/26/2013] [Indexed: 10/26/2022] Open
Abstract
The nucleobase adenine has previously been reported to activate G protein-coupled receptors in rat and mouse. Adenine receptors (AdeR) thus constitute a new family of purine receptors, for which the designation "P0-receptors" has been suggested. We now describe the cloning and characterization of two new members of the AdeR family from mouse (MrgA10, termed mAde1R) and hamster (cAdeR). Both receptors were expressed in Sf9 insect cells, and radioligand binding studies were performed using [(3)H]adenine. Specific binding of the radioligand was detected in transfected, but not in untransfected cells, and K D values of 286 nM (mAde1R, B max 1.18 pmol/mg protein) and 301 nM (cAdeR, B max 17.7 pmol/mg protein), respectively, were determined. A series of adenine derivatives was investigated in competition binding assays. Minor structural modifications generally led to a reduction or loss of affinity, with one exception: 2-fluoroadenine was at least as potent as adenine itself at the cAdeR. Structure-activity relationships at all AdeR orthologs and subtypes investigated so far were similar, but not identical. For functional analyses, the cAdeR was homologously expressed in Chinese hamster ovary (CHO) cells, while the mAde1R was heterologously expressed in 1321N1 astrocytoma cells. Like the previously described AdeRs from rat (rAdeR) and mouse (mAde2R), the mAde1R (EC50 9.77 nM) and the cAdeR (EC50 51.6 nM) were coupled to inhibition of adenylate cyclase. In addition, the cAdeR from hamster expressed in CHO cells produced an increase in intracellular calcium concentrations (EC50 6.24 nM) and was found to be additionally coupled to Gq proteins.
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Affiliation(s)
- Dominik Thimm
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Melanie Knospe
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Aliaa Abdelrahman
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Miguel Moutinho
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Bernt B. A. Alsdorf
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Ivar von Kügelgen
- />PharmaCenter Bonn, Department of Pharmacology, University of Bonn, Sigmund-Freud-Straße 25, 53127 Bonn, Germany
| | - Anke C. Schiedel
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Christa E. Müller
- />PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
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Kishore BK, Zhang Y, Gevorgyan H, Kohan DE, Schiedel AC, Müller CE, Peti-Peterdi J. Cellular localization of adenine receptors in the rat kidney and their functional significance in the inner medullary collecting duct. Am J Physiol Renal Physiol 2013; 305:F1298-305. [PMID: 23986514 DOI: 10.1152/ajprenal.00254.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The Gi-coupled adenine receptor (AdeR) binds adenine with high affinity and potentially reduces cellular cAMP levels. Since cAMP is an important second messenger in the renal transport of water and solutes, we localized AdeR in the rat kidney. Real-time RT-PCR showed higher relative expression of AdeR mRNA in the cortex and outer medulla compared with the inner medulla. Immunoblots using a peptide-derived and affinity-purified rabbit polyclonal antibody specific for an 18-amino acid COOH-terminal sequence of rat AdeR, which we generated, detected two bands between ∼30 and 40 kDa (molecular mass of native protein: 37 kDa) in the cortex, outer medulla, and inner medulla. These bands were ablated by preadsorption of the antibody with the immunizing peptide. Immunofluorescence labeling showed expression of AdeR protein in all regions of the kidney. Immunoperoxidase revealed strong labeling of AdeR protein in the cortical vasculature, including the glomerular arterioles, and less intense labeling in the cells of the collecting duct system. Confocal immunofluorescence imaging colocalized AdeR with aquaporin-2 protein to the apical plasma membrane in the collecting duct. Functionally, adenine (10 μM) significantly decreased (P < 0.01) 1-deamino-8-d-arginine vasopressin (10 nM)-induced cAMP production in ex vivo preparations of inner medullary collecting ducts, which was reversed by PSB-08162 (20 μM, P < 0.01), a selective antagonist of AdeR. Thus, we demonstrated the expression of AdeR in the renal vasculature and collecting ducts and its functional relevance. This study may open a new avenue for the exploration of autocrine/paracrine regulation of renal vascular and tubular functions by the nucleobase adenine in health and disease.
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Affiliation(s)
- Bellamkonda K Kishore
- Nephrology Research (151M Veterans Affairs Salt Lake City Health Care System, 500 Foothill Drive, Salt Lake City, UT 84148.
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Zeng WQ, Zhang JQ, Li Y, Yang K, Chen YP, Liu ZJ. A new method to isolate and culture rat kupffer cells. PLoS One 2013; 8:e70832. [PMID: 23967115 PMCID: PMC3743898 DOI: 10.1371/journal.pone.0070832] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 06/23/2013] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Previous methods for Kupffer cells (KCs) isolation require sophisticated skills and tedious procedures. Few studies have attempted to explore the self-renewal capacity of KCs in vitro. Therefore, the aim of this study was to establish a simple method for rat KCs isolation and further investigate the mitotic potential of KCs in vitro. METHODS KCs were obtained by performing one-step perfusion, enzymatic tissue treatment, differential centrifugation and selective adherence. The proliferation ability of cultured KCs was determined by MTT assay and Propidium Iodide FACS analysis. Phagocytic assay and ED-1, ED-2 immunofluorescence were used to identify cell phenotype. After stimulation with LPS, the expression of surface antigens (MHCII, CD40, CD80, and CD86) and the production of cytokines (NF-κB, TNF-α, IL-6 and IL-10) were measured for cell function identification. RESULTS KCs were isolated with certain numbers and reasonable purities. The KCs were able to survive until at least passage 5 (P5), and at P3 showed equally strong phagocytic activity as primary KCs (P0). After stimulation with LPS, the change in the expression of surface antigens and the production of cytokines for P3 cells was similar to that for P0 cells. CONCLUSIONS Our study provides a simple and efficient method for KCs isolation, and reveals that self-renewing KCs have the same phagocytic activity and functions as primary KCs.
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Affiliation(s)
- Wei-qun Zeng
- Hepatobiliary Surgery Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ji-qin Zhang
- Anesthesia Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yue Li
- Hepatobiliary Surgery Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Kang Yang
- Hepatobiliary Surgery Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yu-pei Chen
- Anesthesia Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zuo-Jin Liu
- Hepatobiliary Surgery Department, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
- * E-mail:
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Translating an understanding of the pathogenesis of hepatic fibrosis to novel therapies. Clin Gastroenterol Hepatol 2013; 11:224-31.e1-5. [PMID: 23305825 PMCID: PMC4151461 DOI: 10.1016/j.cgh.2013.01.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The response to injury is one of wound healing and fibrogenesis, which ultimately leads to fibrosis. The fibrogenic response to injury is a generalized one across virtually all organ systems. In the liver, the injury response, typically occurring over a prolonged period of time, leads to cirrhosis (although it should be pointed out that not all patients with liver injury develop cirrhosis). The fact that many different diseases result in cirrhosis suggests a common pathogenesis. The study of hepatic fibrogenesis over the past 2 decades has been remarkably active, leading to a considerable understanding of this process. It clearly has been shown that the hepatic stellate cell is a central component in the fibrogenic process. It also has been recognized that other effector cells are important in the fibrogenic process, including resident fibroblasts, bone marrow-derived cells, fibrocytes, and even perhaps cells derived from epithelial cells (ie, through epithelial to mesenchymal transition). A key aspect of the biology of fibrogenesis is that the fibrogenic process is dynamic; thus, even advanced fibrosis (or cirrhosis) is reversible. Together, an understanding of the cellular basis for liver fibrogenesis, along with multiple aspects of the basic pathogenesis of fibrosis, have highlighted many exciting potential therapeutic opportunities. Thus, although the most effective antifibrotic therapy is simply treatment of the underlying disease, in situations in which this is not possible, specific antifibrotic therapy is likely not only to become feasible, but will soon become a reality. This review highlights the mechanisms underlying fibrogenesis that may be translated into future antifibrotic therapies and to review the current state of clinical development.
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