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Abdel-Aziz AAM, El-Azab AS, Brogi S, Ayyad RR, Alkahtani HM, Abuelizz HA, Al-Suwaidan IA, Al-Obaid AM. Synthesis, enzyme inhibition assay, and molecular modeling study of novel pyrazolines linked to 4-methylsulfonylphenyl scaffold: antitumor activity and cell cycle analysis. RSC Adv 2024; 14:22132-22146. [PMID: 39005246 PMCID: PMC11240878 DOI: 10.1039/d4ra03902e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Accepted: 06/20/2024] [Indexed: 07/16/2024] Open
Abstract
Antitumor activity using 59 cancer cell lines and enzyme inhibitory activity of a newly synthesized pyrazoline-linked 4-methylsulfonylphenyl scaffold (compounds 18a-q) were measured and compared with those of standard drugs. Pyrazolines 18b, 18c, 18f, 18g, 18h, and 18n possessed significant antitumor activity, with a positive cytotoxic effect (PCE) of 22/59, 21/59, 21/59, 48/59, 51/59, and 20/59, respectively. The cancer cell lines HL60, MCF-7, and MDA-MB-231 were used to measure the IC50 values of derivatives 18c, 18g, and 18hvia the MTT assay method, and the results were compared with those of reference drugs. Derivatives 18g and 18h showed potent and broad-spectrum antitumor activities against HL60 (IC50 of 10.43, 8.99 μM, respectively), MCF-7 (IC50 of 11.7 and 12.4 μM, respectively), and MDA-MB-231 (IC50 of 4.07 and 7.18 μM, respectively). Compound 18c exhibited strong antitumor activity against HL60 and MDA-MB-231 cell lines with IC50 values of 8.43 and 12.54 μM, respectively, and moderate antitumor activity against MCF-7 cell lines with an IC50 value of 16.20 μM. Compounds 18c, 18g, and 18h remarkably inhibited VEGFR2 kinase (IC50 = 0.218, 0.168, and 0.135 μM, respectively) compared with the reference drug sorafenib (IC50 = 0.041 μM). Compounds 18g and 18h effectively inhibited HER2 kinase (IC50 = 0.496 and 0.253 μM, respectively) compared with erlotinib (IC50 = 0.085 μM). Compound 18h inhibited EGFR kinase (IC50 = 0.574 μM) with a potency comparable with that of the reference drug erlotinib (IC50 = 0.105 μM). Pyrazolines 18c, 18f, and 18h arrested the S/G2 phase of the cell cycle in HL-60 cells. In addition, derivatives 18c, 18f, and 18h revealed lower Bcl-2 protein expression anti-apoptotic levels and higher Bax, caspase-3, and caspase-9 expression levels. Molecular docking studies of derivative 18h into the binding sites of EGFR, HER2, and VEGFR2 kinases explored the interaction mode of these pyrazoline derivatives and their structural requirements for antitumor activity.
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Affiliation(s)
- Alaa A-M Abdel-Aziz
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
| | - Adel S El-Azab
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
| | - Simone Brogi
- Department of Pharmacy, University of Pisa Via Bonanno 6 56126 Pisa Italy
| | - Rezk R Ayyad
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-AzharUniversity Cairo Egypt
| | - Hamad M Alkahtani
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
| | - Hatem A Abuelizz
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
| | - Ibrahim A Al-Suwaidan
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
| | - Abdulrahman M Al-Obaid
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University P. O. Box 2457 Riyadh 11451 Saudi Arabia
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Sheng X, Yang Y, Liu J, Yu J, Guo Q, Guan W, Liu F. Down-regulation of miR-18b-5p protects against splenic hemorrhagic shock by directly targeting HIF-1α/iNOS pathway. Immunobiology 2022; 227:152188. [DOI: 10.1016/j.imbio.2022.152188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 01/14/2022] [Accepted: 02/05/2022] [Indexed: 01/15/2023]
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Battin C, De Sousa Linhares A, Paster W, Isenman DE, Wahrmann M, Leitner J, Zlabinger GJ, Steinberger P, Hofer J. Neuropilin-1 Acts as a Receptor for Complement Split Products. Front Immunol 2019; 10:2209. [PMID: 31572401 PMCID: PMC6753332 DOI: 10.3389/fimmu.2019.02209] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/02/2019] [Indexed: 01/07/2023] Open
Abstract
Complement split products (CSPs), such as the fragments C4d and C3d, which are generated as a consequence of complement regulatory processes, are established markers for disease activity in autoimmunity or antibody-mediated graft rejection. Since immunoglobulin-like transcript 4 (ILT4) was previously shown to interact with soluble CSPs, but not with CSPs covalently-bound to target surfaces following classical complement activation, the present study aimed to identify novel cellular receptors interacting with covalently-deposited CSPs. By applying an unbiased screening approach using a cDNA mammalian expression library generated from human monocyte-derived dendritic cells and probed with recombinant human C4d, we identified neuropilin-1 (NRP1) as a novel receptor for C4d, C3d, and iC3b. NRP1, a highly conserved type 1 transmembrane protein, plays important roles in the development of the nervous and cardiovascular system as well as in tumorigenesis through interaction with its established binding partners, such as vascular endothelial growth factor (VEGF) and semaphorin 3A (Sema3A). NRP1 is also expressed on immune cells and serves as a marker for murine Tregs. Although NRP1 contains domains homologous to ones found in some complement proteins, it has not been linked to the complement system. We demonstrate that binding of C4d to NRP1 expressing cells was dose-dependent and saturable, and had a KD value of 0.71 μM. Importantly, and in contrast to ILT4, NRP1 interacted with CSPs that were covalently bound to target surfaces in the course of complement activation, therefore representing a classical complement receptor. The binding site of CSPs was mapped to the b1 domain of the coagulation factor V/VIII homology domain of NRP1. Taken together, our results demonstrate a novel role for NRP1 as a receptor for CSPs deposited on surfaces during complement activation. Further work is required to elucidate the functional consequences of the NRP1-CSP interactions in immunity.
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Affiliation(s)
- Claire Battin
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Annika De Sousa Linhares
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Paster
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria.,Department of Clinical Cell Biology and FACS Core Unit, Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - David E Isenman
- Departments of Biochemistry and Immunology, University of Toronto, Toronto, ON, Canada
| | - Markus Wahrmann
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University Vienna, Vienna, Austria
| | - Judith Leitner
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Gerhard J Zlabinger
- Division of Clinical and Experimental Immunology, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Peter Steinberger
- Division of Immune Receptors and T Cell Activation, Center for Pathophysiology, Infectiology, and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - Johannes Hofer
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University Vienna, Vienna, Austria
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Hajighasemi F, Gheini MH. Lipopolysaccharide Effect on Vascular Endothelial Factor and Matrix Metalloproteinases in Leukemic Cell Lines In vitro. IRANIAN JOURNAL OF CANCER PREVENTION 2015; 8:e2327. [PMID: 26413247 PMCID: PMC4581372 DOI: 10.17795/ijcp2327] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 03/10/2015] [Indexed: 11/25/2022]
Abstract
Background: Angiogenesis, the process of new vessels generation, plays a critical role in tumor invasion and metastasis. Vascular Endothelial Growth Factor (VEGF), as a cytokine, and Matrix Metalloproteinases (MMPs), has been the important factors that involved in angiogenesis. Lipopolysaccharide (LPS) has an essential effect on angiogenesis. Objectives: In this study the effect of LPS on VEGF production and MMP-2/MMP-9 activity in two leukemic cell lines has been assessed in vitro. Materials and Methods: Human leukemic U937 and THP1 cells were cultured in complete RPMI medium. Then the cells at the exponential growth phase were incubated with different concentrations of LPS (0 - 4 μg/mL) for 48 hours. Then the level of VEGF production and MMP-2/MMP-9 activity in cell culture supernatants were evaluated with the ELISA standard kits and gelatin zymography respectively. Results: U937 cells have produced a large amount of VEGF without any stimulus and LPS has not shown any substantial effect on VEGF production by these cells. However THP1 cells have produced a small amount of VEGF without stimulation and LPS significantly has increased VEGF production in these cells dose-dependently. Moreover LPS significantly has augmented the MMP-2/MMP-9 activity in the both leukemic cell lines in a dose-dependent manner. Conclusions: Our results have shown that LPS might be a potential inducer/enhancer of VEGF production and MMP-2/MMP-9 activity (angiogenic factors) in leukemia. Moreover the LPS effect on angiogenesis might be in part, due to its stimulatory effects on VEGF and MMPs. Overall LPS-stimulated leukemic cells might be good models for study and planning the useful therapeutic approaches for angiogenesis- dependent diseases.
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Affiliation(s)
- Fatemeh Hajighasemi
- Department of Immunology, Faculty of Medicine, Shahed University, Tehran, IR Iran
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Huo X, Zhang X, Yu C, Zhang Q, Cheng E, Wang DH, Pham TH, Spechler SJ, Souza RF. In oesophageal squamous cells exposed to acidic bile salt medium, omeprazole inhibits IL-8 expression through effects on nuclear factor-κB and activator protein-1. Gut 2014; 63:1042-52. [PMID: 24048734 PMCID: PMC3959621 DOI: 10.1136/gutjnl-2013-305533] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Oesophagitis might result from the effects of chemokines produced by oesophageal cells in response to gastro-oesophageal reflux, and not solely from the direct, caustic effects of refluxed gastric juice. Proton pump inhibitors (PPI) can block chemokine production through mechanisms independent of their antisecretory effects. We studied omeprazole effects on chemokine production by oesophageal epithelial cells exposed to acidic bile salts. DESIGN Human primary and telomerase-immortalised oesophageal squamous cells were exposed to acidic bile salt medium with or without omeprazole pretreatment. Interleukin (IL)-8 expression was determined by RT-PCR and ELISA. IL-8 promoter activity was measured by luciferase reporter assay. Binding of NF-κB and AP-1 subunits to the IL-8 promoter was assessed by chromatin immunoprecipitation (ChIP) assay. Immune cell migration induced by conditioned medium was determined by a double-chamber migration assay system. RESULTS Acidic bile salt medium caused oesophageal epithelial cells to express IL-8 mRNA and protein by activating the IL-8 promoter through NF-κB and AP-1 binding. Omeprazole inhibited that acidic bile salt-stimulated IL-8 expression by blocking the nuclear translocation of p65 (an NF-κB subunit), and by blocking the binding of p65, c-jun and c-fos (AP-1 subunits) to the IL-8 promoter. Omeprazole also blocked the ability of conditioned medium from cells exposed to acidic bile salts to induce immune cell migration. CONCLUSIONS In oesophageal squamous epithelial cells, omeprazole inhibits IL-8 expression through effects on NF-κB and AP-1 that are entirely independent of effects on gastric acid secretion. These previously unrecognised PPI effects might contribute to the healing of reflux oesophagitis.
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Affiliation(s)
- Xiaofang Huo
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Xi Zhang
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Chunhua Yu
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Qiuyang Zhang
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Edaire Cheng
- Department of Pediatrics, Children’s Medical Center and the University of Texas Southwestern Medical Center, Dallas, Texas
| | - David H. Wang
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Thai H. Pham
- Department of Surgery, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Stuart J. Spechler
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
| | - Rhonda F. Souza
- Department of Internal Medicine, VA North Texas Health Care System and the University of Texas Southwestern Medical School, Dallas, Texas
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Sroka IC, Sandoval CP, Chopra H, Gard JMC, Pawar SC, Cress AE. Macrophage-dependent cleavage of the laminin receptor α6β1 in prostate cancer. Mol Cancer Res 2011; 9:1319-28. [PMID: 21824975 DOI: 10.1158/1541-7786.mcr-11-0080] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The laminin-binding integrin α6β1 plays a major role in determining the aggressive phenotype of tumor cells during metastasis. Our previous work has shown that cleavage of the α6β1 integrin to produce the structural variant α6pβ1 on tumor cell surfaces is mediated by the serine protease urokinase plasminogen activator (uPA). Cleavage of α6β1 increases tumor cell motility, invasion, and prostate cancer metastasis, and blockage of uPA inhibits α6pβ1 production. In human tumors, uPA and uPAR are expressed in tumor cells and tumor-associated macrophages (TAM). TAMs localize to solid tumors and contribute to increased tumor growth and the metastatic phenotype. In this study, we utilized a coculture system of PC-3 prostate tumor cells and macrophages [12-O-tetradecanoylphorbol-13-acetate (TPA)-differentiated human leukemia HL-60 cells] to investigate the hypothesis that macrophages stimulate the production of the prometastatic variant α6pβ1 on human prostate cancer cells via the uPA/uPAR axis. Our results indicate that adherent macrophages cocultured with PC-3 cells increased PC-3 uPAR mRNA, uPAR cell surface protein expression and α6 integrin cleavage. The stimulation does not require macrophage/tumor cell contact because macrophage conditioned medium is sufficient for increased uPAR transcription and α6 cleavage-dependent PC-3 cell invasion. The increased cleavage was dependent on uPAR because production was blocked by silencing RNA-targeting uPAR. These results indicate that macrophages can stimulate uPA/uPAR production in tumor cells which results in α6 integrin cleavage. These data suggest that TAMs promote prometastatic integrin-dependent pericellular proteolysis.
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Affiliation(s)
- Isis C Sroka
- Department of Pharmacology, The University of Arizona, Tucson, AZ 85724, USA
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Nishiura H, Zhao R, Yamamoto T. The role of the ribosomal protein S19 C-terminus in altering the chemotaxis of leucocytes by causing functional differences in the C5a receptor response. J Biochem 2011; 150:271-7. [DOI: 10.1093/jb/mvr067] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Denizot Y. Cyclooxygenase-2, prostaglandin E2 and acute myeloid leukemia. Carcinogenesis 2010; 31:953-953. [DOI: 10.1093/carcin/bgq060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Granata F, Frattini A, Loffredo S, Staiano RI, Petraroli A, Ribatti D, Oslund R, Gelb MH, Lambeau G, Marone G, Triggiani M. Production of vascular endothelial growth factors from human lung macrophages induced by group IIA and group X secreted phospholipases A2. THE JOURNAL OF IMMUNOLOGY 2010; 184:5232-41. [PMID: 20357262 DOI: 10.4049/jimmunol.0902501] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Angiogenesis and lymphangiogenesis mediated by vascular endothelial growth factors (VEGFs) are main features of chronic inflammation and tumors. Secreted phospholipases A(2) (sPLA(2)s) are overexpressed in inflammatory lung diseases and cancer and they activate inflammatory cells by enzymatic and receptor-mediated mechanisms. We investigated the effect of sPLA(2)s on the production of VEGFs from human macrophages purified from the lung tissue of patients undergoing thoracic surgery. Primary macrophages express VEGF-A, VEGF-B, VEGF-C, and VEGF-D at both mRNA and protein level. Two human sPLA(2)s (group IIA and group X) induced the expression and release of VEGF-A and VEGF-C from macrophages. Enzymatically-inactive sPLA(2)s were as effective as the active enzymes in inducing VEGF production. Me-Indoxam and RO092906A, two compounds that block receptor-mediated effects of sPLA(2)s, inhibited group X-induced release of VEGF-A. Inhibition of the MAPK p38 by SB203580 also reduced sPLA(2)-induced release of VEGF-A. Supernatants of group X-activated macrophages induced an angiogenic response in chorioallantoic membranes that was inhibited by Me-Indoxam. Stimulation of macrophages with group X sPLA(2) in the presence of adenosine analogs induced a synergistic increase of VEGF-A release and inhibited TNF-alpha production through a cooperation between A(2A) and A(3) receptors. These results demonstrate that sPLA(2)s induce production of VEGF-A and VEGF-C in human macrophages by a receptor-mediated mechanism independent from sPLA(2) catalytic activity. Thus, sPLA(2)s may play an important role in inflammatory and/or neoplastic angiogenesis and lymphangiogenesis.
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Affiliation(s)
- Francescopaolo Granata
- Division of Clinical Immunology and Allergy and Center for Basic and Clinical Immunology Research, University of Naples Federico II, Naples
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Neuropilin-1 forms complexes with vascular endothelial growth factor receptor-2 during megakaryocytic differentiation of UT-7/TPO cells. Biochem Biophys Res Commun 2009; 390:1171-6. [DOI: 10.1016/j.bbrc.2009.10.110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Accepted: 10/21/2009] [Indexed: 11/22/2022]
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Roncal C, Buysschaert I, Gerdes N, Georgiadou M, Ovchinnikova O, Fischer C, Stassen JM, Moons L, Collen D, De Bock K, Hansson GK, Carmeliet P. Short-term delivery of anti-PlGF antibody delays progression of atherosclerotic plaques to vulnerable lesions. Cardiovasc Res 2009; 86:29-36. [PMID: 19952000 DOI: 10.1093/cvr/cvp380] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
AIMS Placental growth factor (PlGF), a homologue of vascular endothelial growth factor, is a pleiotropic cytokine with a pro-inflammatory activity. Previous gene-inactivation studies revealed that the loss of PlGF delays atherosclerotic lesion development and inhibits macrophage infiltration, but the activity of an anti-PlGF antibody (alphaPlGF mAb) has not been evaluated yet. METHODS AND RESULTS We characterized the potential of short-term delivery of alphaPlGF mAb in inhibiting lesion development in ApoE-deficient mice (apoE(-/-)) and in CD4:TGFbetaRII(DN) x apoE(-/-) mice, a more severe atherosclerosis model. Short-term treatment of alphaPlGF mAb reduces early atherosclerotic plaque size and inflammatory cell infiltration in the lesion. CONCLUSION These pharmacological alphaPlGF mAb results confirm previous genetic evidence that inhibition of PlGF slows down early atherosclerotic lesion development. Furthermore, the phenocopy of genetic and pharmacological loss-of-function strategies underscores that alphaPlGF acts by selectively neutralizing PlGF.
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Affiliation(s)
- Carmen Roncal
- Vesalius Research Center, VIB, KULeuven, Campus Gasthuisberg, Herestraat 49, Box 912, 3000 Leuven, Belgium
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Souza RF, Huo X, Mittal V, Schuler CM, Carmack SW, Zhang HY, Zhang X, Yu C, Hormi-Carver K, Genta RM, Spechler SJ. Gastroesophageal reflux might cause esophagitis through a cytokine-mediated mechanism rather than caustic acid injury. Gastroenterology 2009; 137:1776-84. [PMID: 19660463 DOI: 10.1053/j.gastro.2009.07.055] [Citation(s) in RCA: 274] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Revised: 07/17/2009] [Accepted: 07/22/2009] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Reflux esophagitis is believed to be caused by the caustic effects of refluxed gastric acid on esophageal epithelial cells. However, caustic chemical injuries develop rapidly whereas esophagitis might not appear until weeks after the induction of reflux in animal models. We studied early histologic events in the development of reflux esophagitis in a rat model and performed in vitro experiments to determine whether exposure to acidified bile salts causes esophageal epithelial cells to secrete chemokines that might contribute to inflammation. METHODS At various time points after esophagoduodenostomy, the rat esophagus was removed and inflammatory changes were analyzed by histologic analyses. Human esophageal squamous cell lines were exposed to acidified bile salts to evaluate their effects on cytokine production and immune-cell migration. RESULTS Reflux esophagitis started at postoperative day 3 with lymphocytic infiltration of the submucosa that progressed to the epithelial surface-these findings contradicted those expected from a caustic chemical injury. Basal cell and papillary hyperplasia preceded the development of surface erosions. Exposure of squamous cells to acidified bile salts significantly increased the secretion of interleukin-8 and interleukin-1beta; conditioned media from these cells caused significant increases in the migration rates of T cells and neutrophils. CONCLUSIONS These findings support, but do not prove, an alternative concept for the development of reflux esophagitis in which refluxed gastric juice does not directly damage the esophagus, but rather stimulates esophageal epithelial cells to secrete chemokines that mediate damage of esophageal tissue.
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Affiliation(s)
- Rhonda F Souza
- Department of Medicine, VA North Texas Health Care System and University of Texas Southwestern Medical School, Irving, Texas, USA.
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