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Hoşgörler F, Keleş D, Tanrıverdi-Akhisaroğlu S, İnanç Ş, Akhisaroğlu M, Cankurt Ü, Aydoğdu Z, Uçar AD, Çetinayak O, Oktay G, Arda SG. Anti-inflammatory and Anti-apoptotic Effect of Valproic Acid and Doxycycline Independent from MMP Inhibition in Early Radiation Damage. Balkan Med J 2016; 33:488-495. [PMID: 27761275 DOI: 10.5152/balkanmedj.2016.151304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/07/2016] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Matrix metalloproteinase (MMP) inhibitors decrease inflammation in normal tissues and suppress cancer progress in normal tissues. Valproic acid (VA) and doxycycline (DX) are MMP inhibitors that have radio-protective effects. Their ability to inhibit MMPs in irradiated tissue is unknown and the role of MMPs in radio-protective effects has not been tested to date. AIMS The purpose of this study was to examine whether administration of VA and DX to rats before irradiation affects tissue inflammation and apoptosis in the early phase of radiation, and whether the effect of these drugs is mediated by MMP inhibition. STUDY DESIGN Animal experimentation. METHODS Twenty-six Wistar rats were randomized into four groups: control (CTRL), radiation (RT), VA plus radiation (VA+RT), and DX plus radiation (DX+RT). Three study groups were exposed to a single dose of abdominal 10 Gy gamma radiation; the CTRL group received no radiation. Single doses of VA 300 mg/kg and DX 100 mg/kg were administered to each rat before radiation and all rats were sacrificed 8 hours after irradiation, at which point small intestine tissue samples were taken for analyses. Levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) and matrix metal-loproteinases (MMP-2 and MMP 9) were measured by ELISA, MMP activities were measured by gelatin and casein zymography and apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. RESULTS VA decreased the levels of TNF-α and IL-1β proteins insignificantly and decreased apoptosis significantly in the irradiated tissue, but did not inhibit MMPs. In contrast, VA protected the basal MMP activities, which decreased in response to irradiation. No effect of DX was observed on the levels of inflammatory cytokines or activities of MMPs in the early phases of radiation apoptosis. CONCLUSION Our findings indicated that VA protects against inflammation and apoptosis, and DX exhibits anti-apoptotic effects in early radiation and these effects are independent from MMP inhibition.
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Affiliation(s)
- Ferda Hoşgörler
- Department of General Surgery, Bozyaka Training and Research Hospital, İzmir, Turkey
| | - Didem Keleş
- Department of Medical Biochemistry, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | | | - Şeniz İnanç
- Department of Medical Biochemistry, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | - Mustafa Akhisaroğlu
- Department of Physiology, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | - Ülker Cankurt
- Department of Histology and Embryology, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | - Zekiye Aydoğdu
- Department of Pathology, Dr. Suat Seren Teaching Hospital, İzmir, Turkey
| | - Ahmet Deniz Uçar
- Department of General Surgery, Bozyaka Training and Research Hospital, İzmir, Turkey
| | - Oğuz Çetinayak
- Department of Radiation Oncology, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | - Gülgün Oktay
- Department of Medical Biochemistry, Dokuz Eylül University School of Medicine, İzmir, Turkey
| | - Sevil Gönenç Arda
- Department of Physiology, Dokuz Eylül University School of Medicine, İzmir, Turkey
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Halle M, Christersdottir T, Bäck M. Chronic adventitial inflammation, vasa vasorum expansion, and 5-lipoxygenase up-regulation in irradiated arteries from cancer survivors. FASEB J 2016; 30:3845-3852. [PMID: 27530979 PMCID: PMC5067258 DOI: 10.1096/fj.201600620r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 07/27/2016] [Indexed: 12/31/2022]
Abstract
Radiation-induced cardiovascular disease is an emerging problem in a steadily increasing population of survivors of cancer. However, the underlying biology is poorly described, and the late onset, which occurs several years after exposure, precludes adequate investigations in animal and cell culture models. We investigated the role of the 5-lipoxygenase (5-LO)/leukotriene pathway in radiation-induced vascular changes. Use of paired samples of irradiated arteries and nonirradiated internal control arteries from the same patient that were harvested during surgery for cancer reconstruction ≤10 yr after radiotherapy provides a unique human model of chronic radiation–induced vascular changes. Immunohistochemical stainings and perioperative inspection revealed an adventitial inflammatory response, with vasa vasorum expansion and chronic infiltration of CD68+ macrophages. These macrophages stained positive for the leukotriene-forming enzyme 5-LO. Messenger RNA levels of 5-LO and leukotriene B4 receptor 1 were increased in irradiated arterial segments compared with control vessels. These results point to targeting the 5-LO/leukotriene pathway as a therapeutic adjunct to prevent late adverse vascular effects of radiotherapy.—Halle, M., Christersdottir, T., Bäck, M. Chronic adventitial inflammation, vasa vasorum expansion, and 5-lipoxygenase up-regulation in irradiated arteries from cancer survivors.
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Affiliation(s)
- Martin Halle
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.,Department of Reconstructive Plastic Surgery, Karolinska University Hospital, Stockholm, Sweden
| | - Tinna Christersdottir
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Bäck
- Department of Medicine, Karolinska Institutet, Stockholm, Sweden; and .,Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden
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Abstract
Radiation-induced heart disease (RIHD) is becoming an increasing concern for patients and clinicians alike as the use of radiation therapy for the treatment of certain malignancies increases, and patient mortality secondary to neoplasms of the thorax, in particular Hodgkin's lymphoma and breast cancer, decreases. The spectrum of pathology affecting the heart spans from acute to chronic and can affect almost all facets of the heart, including but not restricted to the pericardial sac, coronary arteries, myocardium, and heart valves. Significant research has been conducted over the past 40 years to further understand the toxic effects of radiation therapy and those protective methods that could curtail these adverse reactions. This article will focus on RIHD, the pathophysiological mechanisms for RIHD, the clinical presentations, and current and future directions for attempting to reduce the incidence of this condition.
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Halle M, Hall P, Tornvall P. Cardiovascular disease associated with radiotherapy: activation of nuclear factor kappa-B. J Intern Med 2011; 269:469-77. [PMID: 21255133 DOI: 10.1111/j.1365-2796.2011.02353.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
There have been several recent reports of an increased risk of cardiovascular disease after radiotherapy. Hence, with an increasing number of cancer survivors, the incidence of cardiovascular disease caused by radiotherapy will increase. The existence of a type of vascular disease, or vasculopathy, induced by radiotherapy has been known for decades. It is important to identify and understand the molecular causes of this vasculopathy to determine preventive strategies. Recently, a chronic inflammation with similarities to atherosclerosis has been observed, with activation of the transcription factor nuclear factor kappa-B (NF-κB) as a possible cause. However, the trigger for NF-κB activation is unclear although it may be that reactive oxygen species or direct DNA damage is involved. To minimize the risk of cardiovascular disease in vulnerable patients, careful selection of patients, radiation dose and fractionation are important, together with the development of new techniques that reduce radiation dose to the blood vessels. In the light of the finding of an interaction between risk factors for cardiovascular disease and radiotherapy, it is reasonable to modify these factors including diabetes mellitus, hyperlipidaemia, hypertension and smoking. We believe that preventive strategies focusing on NF-κB can reduce the risk of future adverse cardiovascular events.
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Affiliation(s)
- M Halle
- Department of Molecular Medicine and Surgery, Section of Reconstructive Plastic Surgery, Karolinska Institutet, Stockholm, Sweden.
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Lee EK, Kim JM, Choi J, Jung KJ, Kim DH, Chung SW, Ha YM, Yu BP, Chung HY. Modulation of NF-κB and FOXOs by baicalein attenuates the radiation-induced inflammatory process in mouse kidney. Free Radic Res 2011; 45:507-17. [DOI: 10.3109/10715762.2011.555479] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Halle M, Ekström M, Farnebo F, Tornvall P. Endothelial activation with prothrombotic response in irradiated microvascular recipient veins. J Plast Reconstr Aesthet Surg 2010; 63:1910-6. [DOI: 10.1016/j.bjps.2009.12.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 09/23/2009] [Accepted: 12/02/2009] [Indexed: 10/19/2022]
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Sottnik JL, Hansen RJ, Gustafson DL, Dow SW, Thamm DH. Induction of VEGF by tepoxalin does not lead to increased tumour growth in a canine osteosarcoma xenograft. Vet Comp Oncol 2010; 9:118-30. [PMID: 21569197 DOI: 10.1111/j.1476-5829.2010.00240.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The purpose of this study was to determine the impact of the non-steroidal anti-inflammatory drug tepoxalin on canine tumour cell growth and describe the changes associated with tepoxalin treatment. In vitro experiments were performed to assess tepoxalin-associated alterations in tumour cell growth. Clinically achievable tepoxalin concentrations did not significantly alter tumour cell growth in vitro. Vascular endothelial growth factor (VEGF) production and hypoxia-inducible factor-1α dose-dependently increased in vitro in the presence of tepoxalin. A canine osteosarcoma xenograft was used to determine in vivo effects of tepoxalin on tumour growth and angiogenesis. Despite increased VEGF in vitro, there was a significant growth delay associated with tepoxalin treatment. Normal dogs were administered tepoxalin to assess effects on systemic VEGF production, but not found to have significantly increased VEGF. These data suggest that tepoxalin may moderately inhibit tumour growth and may be administered as an analgesic to tumour-bearing dogs.
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Affiliation(s)
- J L Sottnik
- Department of Clinical Sciences, Animal Cancer Center, Colorado State University, 300 West Drake Road, Fort Collins, CO 80523, USA
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Halle M, Gabrielsen A, Paulsson-Berne G, Gahm C, Agardh HE, Farnebo F, Tornvall P. Sustained inflammation due to nuclear factor-kappa B activation in irradiated human arteries. J Am Coll Cardiol 2010; 55:1227-1236. [PMID: 20298930 DOI: 10.1016/j.jacc.2009.10.047] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2009] [Revised: 09/22/2009] [Accepted: 10/27/2009] [Indexed: 12/15/2022]
Abstract
OBJECTIVES The aim of this study was to investigate gene expression networks related to cardiovascular disease in radiated human arteries. BACKGROUND Recent epidemiological studies have shown that radiotherapy is associated with cardiovascular disease years after treatment. However, the molecular mechanisms underlying late effects of radiation are poorly described. METHODS Arterial biopsies from radiated and nonradiated human conduit arteries, from the same patient, were simultaneously harvested during microvascular free tissue transfer for cancer-reconstruction in 13 patients, 4 to 500 weeks from radiation treatment. Radiated and nonradiated arteries were compared, with Affymetrix (Santa Clara, California) microarrays on a subset of the material to generate candidate genes. A Taqman (Applied Biosystems, Foster City, California) low-density array of 45 selected genes was designed for analysis of the whole material. RESULTS Thirteen genes were synchronously expressed in all patients (p = 0.0015), including CCL8, CCL3, CXCL2, DUSP5, FGFR2, HMOX1, HOXA9, IL-6, MMP-1, PTX3, RDH10, SOD2, and TNFAIP3. A majority of differentially regulated genes related to the nuclear factor-kappa B (NF-kappaB) signaling pathway and were dysregulated even years after radiation. The NF-kappaB activation was confirmed by immunohistochemistry and immunofluorescence. CONCLUSIONS In the present study, we found sustained inflammation due to NF-kappaB activation in human radiated arteries. The results are supported by previous in vitro findings suggesting that deoxyribonucleic acid injury, after radiation, activates NF-kappaB. We also suggest that HOXA9 might be involved in the regulation of NF-kappaB activation. The observed sustained inflammatory response can explain cardiovascular disease years after radiation.
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Affiliation(s)
- Martin Halle
- Department of Molecular Medicine and Surgery, Section of Reconstructive Plastic Surgery, Karolinska Institute, Stockholm, Sweden; Department of Medicine, Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden.
| | - Anders Gabrielsen
- Department of Medicine, Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden; Department of Medicine, Section of Cardiology, Karolinska Institute, Stockholm, Sweden
| | | | - Caroline Gahm
- Department of ORL, Head and Neck Surgery, Karolinska Institute, Stockholm, Sweden
| | - Hanna E Agardh
- Department of Medicine, Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden
| | - Filip Farnebo
- Department of Molecular Medicine and Surgery, Section of Reconstructive Plastic Surgery, Karolinska Institute, Stockholm, Sweden
| | - Per Tornvall
- Department of Medicine, Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden; Department of Medicine, Section of Cardiology, Karolinska Institute, Stockholm, Sweden
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Abstract
Radiation induces an important inflammatory response in the irradiated organs, characterized by leukocyte infiltration and vascular changes that are the main limiting factor in the application of this therapeutic modality for the treatment of cancer. Recently, a considerable investigative effort has been directed at determining the molecular mechanisms by which radiation induces leukocyte recruitment, in order to create strategies to prevent intestinal inflammatory damage. In these review, we consider current available evidence on the factors governing the process of leukocyte recruitment in irradiated organs, mainly derived from experimental studies, with special attention to adhesion molecules, and their value as therapeutic targets.
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Affiliation(s)
- Meritxell Molla
- Radioncology Department, Instituto Oncologico Teknon, c/Vilana 12, 08022 Barcelona, Spain.
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Sharma M, McCarthy ET, Sharma R, Fish BL, Savin VJ, Cohen EP, Moulder JE. Arachidonic acid metabolites mediate the radiation-induced increase in glomerular albumin permeability. Exp Biol Med (Maywood) 2006; 231:99-106. [PMID: 16380650 DOI: 10.1177/153537020623100112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Radiation-induced renal injury is characterized by proteinuria, hypertension, and progressive decline in renal function. We have previously shown that in vivo or in vitro irradiation of glomeruli with a single dose of radiation (9.5 Gy) increases glomerular albumin permeability (P(alb)) within 1 hr. The current studies tested the hypothesis that this early radiation-induced increase in P(alb) is caused by the release of arachidonic acid and by the generation of specific arachidonic acid metabolites. Glomeruli obtained from WAG/Rij/MCW rats and cultured rat glomerular epithelial and mesangial cells were studied after irradiation (9.5 Gy, single dose). Arachidonic acid release and eicosanoid synthesis by glomeruli or cultured glomerular cells were measured after irradiation, and the effect of inhibitors of phospholipase A2 (PLA2) and cyclooxygenase (COX) on the irradiation-induced increase in P(alb) was assessed. Arachidonic acid release was demonstrated within 10 mins of irradiation of isolated glomeruli and monolayer cultures of glomerular epithelial and mesangial cells. Prostaglandin F(2alpha) (PGF(2alpha)) and PGE2 release was increased after irradiation of isolated glomeruli. Blocking arachidonic acid release or COX activity before irradiation completely prevented the increase in P(alb). COX inhibition immediately after irradiation also diminished the radiation-induced increase in P(alb). We conclude that arachidonic acid and its COX metabolites play an essential role in the early cellular changes that lead to the radiation-induced increase in P(alb). Understanding of the early epigenetic effects of irradiation may lead to new intervention strategies against radiation-induced injury of normal tissues.
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Affiliation(s)
- Mukut Sharma
- Division of Nephrology and the Kidney Disease Center, Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
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Gaugler MH, Vereycken-Holler V, Squiban C, Vandamme M, Vozenin-Brotons MC, Benderitter M. Pravastatin limits endothelial activation after irradiation and decreases the resulting inflammatory and thrombotic responses. Radiat Res 2005; 163:479-87. [PMID: 15850408 DOI: 10.1667/rr3302] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Endothelial dysfunction has been implicated in the pathogenesis of atherosclerosis, fibrosis and vascular occlusion after radiation therapy. Statins have been reported to improve endothelial function; however, this beneficial effect on endothelial cells has never been investigated after irradiation. Therefore, using human microvascular endothelial cells from lung that had been irradiated with 5 or 10 Gy, we assessed the effect of pravastatin on endothelial activation by ELISA, cell-ELISA and electrophoretic mobility shift assay and increased blood-endothelial cell interactions by a flow adhesion assay. Pravastatin inhibited the overproduction of monocyte chemoattractant protein 1, IL6 and IL8 and the enhanced expression of intercellular adhesion molecule 1 but had no effect on platelet-endothelial cell adhesion molecule 1 expression. Moreover, pravastatin down-regulated the radiation-induced activation of the transcription factor activator protein 1 but not of nuclear factor-kappaB. Finally, an inhibition by pravastatin of increased adhesion of leukocytes and platelets to irradiated endothelial cells was observed. The effect of pravastatin was maintained up to 14 days after irradiation and was reversed by mevalonate. Pravastatin exerts persistent anti-inflammatory and anti-thrombotic effects on irradiated endothelial cells. Statins may be considered in therapeutic strategies for the management of patients treated with radiation therapy.
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Affiliation(s)
- Marie-Hélène Gaugler
- Institut de Radioprotection et de Sûreté Nucléaire, IRSN/DRPH/SRBE, F-92262 Fontenay-aux-Roses Cedex, France.
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Weder JE, Dillon CT, Hambley TW, Kennedy BJ, Lay PA, Biffin J, Regtop HL, Davies NM. Copper complexes of non-steroidal anti-inflammatory drugs: an opportunity yet to be realized. Coord Chem Rev 2002. [DOI: 10.1016/s0010-8545(02)00086-3] [Citation(s) in RCA: 360] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Morel E, Dublineau I, Lebrun F, Griffiths NM. Alterations of the VIP-stimulated cAMP pathway in rat distal colon after abdominal irradiation. Am J Physiol Gastrointest Liver Physiol 2002; 282:G835-43. [PMID: 11960780 DOI: 10.1152/ajpgi.00457.2001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ionizing radiation induces hyporesponsiveness of rat colonic mucosa to vasoactive intestinal peptide (VIP). Possible mechanisms responsible for this hyporesponsiveness of the cAMP communication pathway in rat colon were investigated. VIP- and forskolin-stimulated short-circuit current (I(sc)) responses were studied after a 10-Gy abdominal irradiation in Ussing chambers as well as in single, isolated crypts. Adenylyl cyclase (AC) activity and VIP receptor characteristics were determined in mucosal membrane preparations. In addition, alterations in crypt morphology were studied. Impaired secretory responses to VIP and forskolin were observed 4 days after irradiation (decrease of 80%). cAMP analog-stimulated I(sc) responses were unchanged. In isolated crypts, VIP- and forskolin-stimulated cAMP accumulation was markedly reduced by 80 and 50%, respectively. VIP-stimulated AC activity and VIP receptor number were decreased in membrane preparations. No major change of cellularity was associated with these functional alterations. In conclusion, the decreased secretory responses to VIP of rat colon are associated with reduced cAMP accumulation, decreased AC activity, and diminution of VIP receptor numbers without a marked decrease of crypt cell number.
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Affiliation(s)
- E Morel
- Institut de Protection et de Sûreté Nucléaire, Département de Protection et de la santé de l'Homme et de Dosimétrie, Section Autonome de Radiobiologie Appliquée à la Médecine, F-92265 Fontenay-aux-Roses Cedex, France
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Mollà M, Biete A, Piqué J, Panés J. [Intestinal lesions from radiotherapy]. GASTROENTEROLOGIA Y HEPATOLOGIA 2001; 24:454-60. [PMID: 11722824 DOI: 10.1016/s0210-5705(01)79002-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M Mollà
- Servicio de Oncología Radioterápica. Institut Clínic de Malalties Hemato-Oncològiques, Spain.
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Mollà M, Gironella M, Salas A, Miquel R, Pérez-del-Pulgar S, Conill C, Engel P, Biete A, Piqué JM, Panés J. Role of P-selectin in radiation-induced intestinal inflammatory damage. Int J Cancer 2001; 96:99-109. [PMID: 11291093 DOI: 10.1002/ijc.1009] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The aims of our study were to characterize the dose- and time-dependent changes in endothelial P-selectin expression and the role of this adhesion molecule as a mediator of radiation-induced inflammation. For that purpose, endothelial P-selectin expression was measured by the radiolabeled antibody technique in control and irradiated mice at 2, 6, and 24 hr following abdominal irradiation with 4 or 10 Gy; leukocyte endothelial cell interactions were assessed using intravital microscopy in intestinal venules following irradiation at the aforementioned doses and times in C57BL/6 and P-selectin-deficient mice. In wild-type mice, radiation induced a time- and dose-dependent up-regulation of P-selectin and a significant increase in the flux of rolling leukocytes 2 hr after irradiation. Irradiation induced a significant increase in leukocyte adhesion that was dose-dependent. Following irradiation, P-selectin-deficient mice did not show any increase in leukocyte rolling but did demonstrate a response in leukocyte adhesion similar to that of the wild-type mice. Radiation-induced dose-dependent histological inflammatory damage that did not differ between P-selectin-deficient and wild-type mice. We conclude that P-selectin is up-regulated following irradiation and is a key molecular determinant of leukocyte rolling but not leukocyte adhesion in this inflammatory condition. Therefore, isolated neutralization of this adhesion molecule is not an effective means for preventing radiation-induced inflammation.
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Affiliation(s)
- M Mollà
- Department of Gastroenterology, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pí i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
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