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Aminoshariae A, Donaldson M, Horan M, Kulild JC, Baur D. Perioperative Antiplatelet and Anticoagulant Management with Endodontic Microsurgical Techniques. J Endod 2021; 47:1557-1565. [PMID: 34265324 DOI: 10.1016/j.joen.2021.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/23/2021] [Accepted: 07/01/2021] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The purpose of this study was to review evidence-based recommendations for the safe perioperative management of patients undergoing endodontic microsurgery who are currently taking antiplatelet or anticoagulant medications. Using the PICO (Population, Intervention, Comparison, Outcome) format, the following scientific question was asked: In patients taking anticoagulant or antiplatelet agents, what is the available evidence in the management of endodontic microsurgery? METHODS MEDLINE, Scopus, Cochrane Library, and ClinicalTrials.gov databases were searched to identify current recommendations regarding the management of antiplatelet and anticoagulant medications in the context of outpatient dental surgical procedures. Additionally, the authors hand searched the bibliographies of all relevant articles, the gray literature, and textbooks. Because of the lack of clinical studies and evidence on this subject, articles and guidelines from other organizations and association position statements were included. RESULTS Because any minor surgery can become a major surgery, the treating doctor needs to best assess the risk of bleeding, especially if the surgery is anticipated to take longer than 45 minutes. Every patient should be stratified on a case-by-case basis. Consultation with the patient's physician is highly recommended. CONCLUSIONS In order to maximize the effects of these medications (to prevent thrombosis) while minimizing the potential risks (procedural hemorrhage), clinicians should be aware of the best available evidence when considering continuation or discontinuation of antiplatelet and anticoagulant agents perioperatively for endodontic microsurgery. Ideally, a joint effort from an expert panel for microsurgery would be warranted.
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Affiliation(s)
- Anita Aminoshariae
- Departments of Endodontics, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio.
| | - Mark Donaldson
- School of Pharmacy, University of Montana, Missoula, Montana; School of Dentistry, Oregon Health and Sciences University, Portland, Oregon
| | - Michael Horan
- Oral and Maxillofacial Surgery, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio
| | - James C Kulild
- UKMC Dental School, University of Missouri-Kansas City, Kansas City, Missouri
| | - Dale Baur
- Oral and Maxillofacial Surgery, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio
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2
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Titmarsh DM, Nurcombe V, Cheung C, Cool SM. Vascular Cells and Tissue Constructs Derived from Human Pluripotent Stem Cells for Toxicological Screening. Stem Cells Dev 2019; 28:1347-1364. [PMID: 31397206 DOI: 10.1089/scd.2018.0246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The ability of human stem cells to generate somatic cell lineages makes them ideal candidates for use in toxicological testing and eventually, preclinical drug development. Such resources would support an evolution away from human primary cells or research animal models, which suffer from variability and poor predictability, toward off-the-shelf assays of chemical toxicity and drug efficacy using human cells and tissues. To this end, we generated vascular cell populations (smooth muscle cells and endothelial cells) from human pluripotent stem cells (hPSCs), arranged them into 3D co-cultures within supportive gel matrices, and directed their propensity for self-organization resembling microvasculature. The resulting vascular cell populations and co-cultured constructs were then arrayed in high throughput and used for screening a library of environmental and clinical chemical agents for immunological and toxicological responses. The screen effectively stratified the chemicals into various levels of toxicity, with both cell type-specific and co-culture-dependent responses observed. Thus, hPSC-derived vascular cells and constructs could be progressed further toward use in toxicant and drug screening.
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Affiliation(s)
- Drew M Titmarsh
- Institute of Medical Biology and Agency for Science Technology and Research (A*STAR), Singapore, Singapore
| | - Victor Nurcombe
- Institute of Medical Biology and Agency for Science Technology and Research (A*STAR), Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University-Imperial College London, Singapore, Singapore
| | - Christine Cheung
- Lee Kong Chian School of Medicine, Nanyang Technological University-Imperial College London, Singapore, Singapore.,Institute of Molecular and Cell Biology, Agency for Science Technology and Research (A*STAR), Singapore, Singapore
| | - Simon M Cool
- Institute of Medical Biology and Agency for Science Technology and Research (A*STAR), Singapore, Singapore.,Department of Orthopaedic Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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Hoganson DM, Finkelstein EB, Owens GE, Hsiao JC, Eng KY, Kulig KM, Kim ES, Kniazeva T, Pomerantseva I, Neville CM, Turk JR, Fermini B, Borenstein JT, Vacanti JP. A bilayer small diameter in vitro vascular model for evaluation of drug induced vascular injury. BIOMICROFLUIDICS 2016; 10:054116. [PMID: 27795748 PMCID: PMC5065573 DOI: 10.1063/1.4964814] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 10/02/2016] [Indexed: 06/06/2023]
Abstract
In pre-clinical safety studies, drug-induced vascular injury (DIVI) is defined as an adverse response to a drug characterized by degenerative and hyperplastic changes of endothelial cells and vascular smooth muscle cells. Inflammation may also be seen, along with extravasation of red blood cells into the smooth muscle layer (i.e., hemorrhage). Drugs that cause DIVI are often discontinued from development after considerable cost has occurred. An in vitro vascular model has been developed using endothelial and smooth muscle cells in co-culture across a porous membrane mimicking the internal elastic lamina. Arterial flow rates of perfusion media within the endothelial chamber of the model induce physiologic endothelial cell alignment. Pilot testing with a drug known to cause DIVI induced extravasation of red blood cells into the smooth muscle layer in all devices with no extravasation seen in control devices. This engineered vascular model offers the potential to evaluate candidate drugs for DIVI early in the discovery process. The physiologic flow within the co-culture model also makes it candidate for a wide variety of vascular biology investigations.
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Affiliation(s)
| | - Eric B Finkelstein
- Syracuse Biomaterials Institute and Department of Biomedical and Chemical Engineering, Syracuse University , Syracuse, New York 13244, USA
| | - Gwen E Owens
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital , Boston, Massachusetts 02114, USA
| | - James C Hsiao
- Draper Laboratories , Cambridge, Massachusetts 02139, USA
| | - Kurt Y Eng
- Pfizer Inc. , Cambridge, Massachusetts 02139, USA
| | - Katherine M Kulig
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital , Boston, Massachusetts 02114, USA
| | - Ernest S Kim
- Draper Laboratories , Cambridge, Massachusetts 02139, USA
| | | | - Irina Pomerantseva
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital , Boston, Massachusetts 02114, USA
| | - Craig M Neville
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital , Boston, Massachusetts 02114, USA
| | | | | | | | - Joseph P Vacanti
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital , Boston, Massachusetts 02114, USA
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4
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Frazier KS, Engelhardt JA, Fant P, Guionaud S, Henry SP, Leach MW, Louden C, Scicchitano MS, Weaver JL, Zabka TS. Scientific and Regulatory Policy Committee Points-to-consider Paper*. Toxicol Pathol 2015; 43:915-34. [DOI: 10.1177/0192623315570340] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Drug-induced vascular injury (DIVI) is a recurrent challenge in the development of novel pharmaceutical agents. Although DIVI in laboratory animal species has been well characterized for vasoactive small molecules, there is little available information regarding DIVI associated with biotherapeutics such as peptides/proteins or antibodies. Because of the uncertainty about whether DIVI in preclinical studies is predictive of effects in humans and the lack of robust biomarkers of DIVI, preclinical DIVI findings can cause considerable delays in or even halt development of promising new drugs. This review discusses standard terminology, characteristics, and mechanisms of DIVI associated with biotherapeutics. Guidance and points to consider for the toxicologist and pathologist facing preclinical cases of biotherapeutic-related DIVI are outlined, and examples of regulatory feedback for each of the mechanistic types of DIVI are included to provide insight into risk assessment.
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Affiliation(s)
| | | | | | | | | | - Michael W. Leach
- Pfizer—Drug Safety Research and Development, Andover, Massachusetts, USA
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5
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Mikaelian I, Cameron M, Dalmas DA, Enerson BE, Gonzalez RJ, Guionaud S, Hoffmann PK, King NMP, Lawton MP, Scicchitano MS, Smith HW, Thomas RA, Weaver JL, Zabka TS. Nonclinical Safety Biomarkers of Drug-induced Vascular Injury. Toxicol Pathol 2014; 42:635-57. [DOI: 10.1177/0192623314525686] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Better biomarkers are needed to identify, characterize, and/or monitor drug-induced vascular injury (DIVI) in nonclinical species and patients. The Predictive Safety Testing Consortium (PSTC), a precompetitive collaboration of pharmaceutical companies and the U.S. Food and Drug Administration (FDA), formed the Vascular Injury Working Group (VIWG) to develop and qualify translatable biomarkers of DIVI. The VIWG focused its research on acute DIVI because early detection for clinical and nonclinical safety monitoring is desirable. The VIWG developed a strategy based on the premise that biomarkers of DIVI in rat would be translatable to humans due to the morphologic similarity of vascular injury between species regardless of mechanism. The histomorphologic lexicon for DIVI in rat defines degenerative and adaptive findings of the vascular endothelium and smooth muscles, and characterizes inflammatory components. We describe the mechanisms of these changes and their associations with candidate biomarkers for which advanced analytical method validation was completed. Further development is recommended for circulating microRNAs, endothelial microparticles, and imaging techniques. Recommendations for sample collection and processing, analytical methods, and confirmation of target localization using immunohistochemistry and in situ hybridization are described. The methods described are anticipated to aid in the identification and qualification of translational biomarkers for DIVI.
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Affiliation(s)
- Igor Mikaelian
- Hoffmann-La Roche Inc, Nutley, New Jersey, USA
- Abbvie, Worcester, Massachusetts, USA
| | | | | | | | - Raymond J. Gonzalez
- Merck Research Laboratories, Merck and Co, Inc, West Point, Pennsylvania, USA
| | - Silvia Guionaud
- Shire, Hampshire International Business Park, Basingstoke, United Kingdom
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6
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Bendjama K, Guionaud S, Aras G, Arber N, Badimon L, Bamberger U, Bratfalean D, Brott D, David M, Doessegger L, Firat H, Gallas JF, Gautier JC, Hoffmann P, Kraus S, Padro T, Saadoun D, Szczesny P, Thomann P, Vilahur G, Lawton M, Cacoub P. Translation Strategy for the Qualification of Drug-induced Vascular Injury Biomarkers. Toxicol Pathol 2014; 42:658-71. [DOI: 10.1177/0192623314527644] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Drug-induced vascular injury (DIVI) is a common preclinical toxicity usually characterized by hemorrhage, vascular endothelial and smooth muscle damage, and inflammation. DIVI findings can cause delays or termination of drug candidates due to low safety margins. The situation is complicated by the absence of sensitive, noninvasive biomarkers for monitoring vascular injury and the uncertain relevance to humans. The Safer And Faster Evidence-based Translation (SAFE-T) consortium is a public–private partnership funded within the European Commission’s Innovative Medicines Initiative (IMI) aiming to accelerate drug development by qualifying biomarkers for drug-induced organ injuries, including DIVI. The group is using patients with vascular diseases that have key histomorphologic features (endothelial damage, smooth muscle damage, and inflammation) in common with those observed in DIVI, and has selected candidate biomarkers associated with these features. Studied populations include healthy volunteers, patients with spontaneous vasculitides and other vascular disorders. Initial results from studies with healthy volunteers and patients with vasculitides show that a panel of biomarkers can successfully discriminate the population groups. The SAFE-T group plans to seek endorsement from health authorities (European Medicines Agency and Food and Drug Administration) to qualify the biomarkers for use in regulatory decision-making processes.
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Affiliation(s)
| | | | | | - Nadir Arber
- Integrated Cancer Prevention Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Lina Badimon
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Uwe Bamberger
- Boehringer Ingelheim Pharma GmbH & Co. KG Nonclinical Drug Safety Biberach/Riss, Germany
| | | | - David Brott
- AstraZeneca Pharmaceuticals, Translational Patient Safety and Enabling Sciences, Wilmington, Delaware, USA
| | - Maayan David
- Integrated Cancer Prevention Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | | | | | | | | | - Peter Hoffmann
- Novartis Pharmaceuticals Corporation, Preclinical safety, East Hanover, New Jersey, USA
| | - Sarah Kraus
- Integrated Cancer Prevention Center, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Teresa Padro
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - David Saadoun
- Assistance Publique-Hôpitaux de Paris (AP-HP), Groupe Hospitalier Pitié-Salpêtrière, Department of Internal Medicine and Clinical Immunology, F-75013, Paris, France; Département Hospitalo-Universitaire I2B, UPMC Univ Paris 06, F-75005, Paris, France; INSERM UMR 7211, F-75005, Paris, France; INSERM, UMR_S 959, F-75013, Paris, France; CNRS, UMR 7211, F-75005, Paris, France
| | | | | | - Gemma Vilahur
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Michael Lawton
- Pfizer Worldwide Research & Development, Drug Safety Research & Development, Groton, Connecticut, USA
| | - Patrice Cacoub
- Assistance Publique-Hôpitaux de Paris (AP-HP), Groupe Hospitalier Pitié-Salpêtrière, Department of Internal Medicine and Clinical Immunology, F-75013, Paris, France; Département Hospitalo-Universitaire I2B, UPMC Univ Paris 06, F-75005, Paris, France; INSERM UMR 7211, F-75005, Paris, France; INSERM, UMR_S 959, F-75013, Paris, France; CNRS, UMR 7211, F-75005, Paris, France
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Swanson TA, Conte T, Deeley B, Portugal S, Kreeger JM, Obert LA, Joseph EC, Wisialowski TA, Sokolowski SA, Rief C, Nugent P, Lawton MP, Enerson BE. Hemodynamic Correlates of Drug-induced Vascular Injury in the Rat Using High-frequency Ultrasound Imaging. Toxicol Pathol 2014; 42:784-91. [DOI: 10.1177/0192623314525687] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Several classes of drugs have been shown to cause drug-induced vascular injury (DIVI) in preclinical toxicity studies. Measurement of blood flow and vessel diameter in numerous vessels and across various tissues by ultrasound imaging has the potential to be a noninvasive translatable biomarker of DIVI. Our objective was to demonstrate the utility of high-frequency ultrasound imaging for measuring changes in vascular function by evaluating blood flow and vessel diameter in the superior mesenteric arteries (SMA) of rats treated with compounds that are known to cause DIVI and are known vasodilators in rat: fenoldopam, CI-1044, and SK&F 95654. Blood flow, vessel diameter, and other parameters were measured in the SMA at 4, 8, and 24 hr after dosing. Mild to moderate perivascular accumulations of mononuclear cells, neutrophils in tunica adventitia, and superficial tunica media as well as multifocal hemorrhage and necrosis in the tunica media were found in animals 24 hr after treatment with fenoldopam and SK&F 95654. Each compound caused marked increases in blood flow and shear stress as early as 4 hr after dosing. These results suggest that ultrasound imaging may constitute a functional correlate for the microscopic finding of DIVI in the rat.
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Affiliation(s)
- Terri A. Swanson
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
| | - Teri Conte
- FUJIFILM VisualSonics, Inc., Toronto, Ontario, Canada
| | - Ben Deeley
- FUJIFILM VisualSonics, Inc., Toronto, Ontario, Canada
| | - Susan Portugal
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
| | - John M. Kreeger
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
| | - Leslie A. Obert
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
| | - E. Clive Joseph
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
| | | | | | - Catherine Rief
- Pfizer Worldwide Research and Development, Andover, Massachusetts, USA
| | - Paul Nugent
- Pfizer Worldwide Research and Development, Groton, Connecticut, USA
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Bodié K, Decker JH. Incidental Histopathological Findings in Hearts of Control Beagle Dogs in Toxicity Studies. Toxicol Pathol 2013; 42:997-1003. [DOI: 10.1177/0192623313508480] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In preclinical studies of pharmaceutical agents, the beagle dog is a commonly used model for the detection of cardiotoxicity. Incidental findings, postmortem changes, and artifacts must be distinguished histopathologically from test item–related findings in the heart. In this retrospective analysis, cardiac sections from 88 control beagles (41 male, 47 female; ages 5–18 months) in preclinical studies were examined histopathologically. The most common finding was thickening of the tunica media of intramural coronary arteries, most likely a postmortem change. The second most common finding was the presence of vacuoles within Purkinje fibers. Dilated lymphatic and blood vessels at the insertion of chordae tendineae were noted more commonly in males than in females and were considered a normal anatomic feature. Mesothelial-lined papillary fronds along the epicardial surface of the atria were present in several dogs, as were small infiltrates of inflammatory cells usually within the myocardium. In summary, control beagles’ hearts frequently have incidental findings that must be differentiated from test item–related pathologic changes. Historical control data can be useful for the interpretation of incidental and test item–related findings in the beagle heart.
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Affiliation(s)
- Karen Bodié
- Preclinical Safety, AbbVie Deutschland GmbH & Co. KG, Ludwigshafen, Germany
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Brott DA, Richardson RJ, Louden CS. Evidence for the nitric oxide pathway as a potential mode of action in fenoldopam-induced vascular injury. Toxicol Pathol 2012; 40:874-86. [PMID: 22549976 DOI: 10.1177/0192623312444027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Fenoldopam, a dopaminergic DA1 agonist, induces vasodilatation via nitric oxide (NO), and this may be associated with mesenteric arterial injury. NO is produced from the enzymatic action of nitric oxide synthase (NOS), which is regulated by the shear-stress mediating protein caveolin-1. Profound vasodilatation and accompanied decreased shear are early events that could initiate vascular injury. Therefore, it is of interest to determine the role of caveolin-1 and the NO pathway in fenoldopam-induced vascular injury. At sites of fenoldopam-induced mesenteric arterial injury, decreased caveolin-1 expression and apoptosis were prominent immunohistochemical findings. An additional finding at these sites of injury were loss and/or reduced expression of caveolin-1 regulated structural proteins, connexin-43, (gap junction) ZO-1, and claudin (tight junctions). Because functional loss of caveolin-1 is associated with increased NOS activity and vasodilatation via NO, studies were conducted to show a NO donor produced vascular lesions in the mesenteric arteries morphologically similar to those induced by fenoldopam. Moreover, the incidence and severity of fenoldopam-induced vascular injury were reduced when an NOS inhibitor or a scavenger of NO-generated free radicals were coadministered with fenoldopam. Collectively, these data suggest that caveolin-1 and its regulated NO pathway may play an important role in vasodilatory drug-induced vascular injury.
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Affiliation(s)
- David A Brott
- AstraZeneca Pharmaceuticals, Wilmington, Delaware 19850, USA.
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Giembycz MA, Newton R. Harnessing the clinical efficacy of phosphodiesterase 4 inhibitors in inflammatory lung diseases: dual-selective phosphodiesterase inhibitors and novel combination therapies. Handb Exp Pharmacol 2011:415-446. [PMID: 21695651 DOI: 10.1007/978-3-642-17969-3_18] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Phosphodiesterase (PDE) 4 inhibitors have been in development as a novel anti-inflammatory therapy for more than 20 years, with asthma and chronic obstructive pulmonary disease (COPD) being primary indications. Despite initial optimism, only one selective PDE4 inhibitor, roflumilast (Daxas (®)), has been approved for use in humans and available in Canada and the European Union in 2011 for the treatment of a specific population of patients with severe COPD. In many other cases, the development of PDE4 inhibitors of various structural classes has been discontinued due to lack of efficacy and/or dose-limiting adverse events. Indeed, for many of these compounds, it is likely that the maximum tolerated dose is either subtherapeutic or at the very bottom of the efficacy dose-response curve. Thus, a significant ongoing challenge that faces the pharmaceutical industry is to synthesize compounds with therapeutic ratios that are superior to roflumilast. Several strategies are being considered, but clinically effective compounds with an optimal pharmacophore have not, thus far, been reported. In this chapter, alternative means of harnessing the clinical efficacy of PDE4 inhibitors are described. These concepts are based on the assumption that additive or synergistic anti-inflammatory effects can be produced with inhibitors that target either two or more PDE families or with a PDE4 inhibitor in combination with other anti-inflammatory drugs such as a glucocorticoid.
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Affiliation(s)
- Mark A Giembycz
- Airways Inflammation Research Group, Departments of Physiology and Pharmacology, Institute of Infection, Immunity and Inflammation, University of Calgary, 3280 Hospital Drive NW, Calgary, AB T2N 4N1, Canada.
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Ettlin RA, Kuroda J, Plassmann S, Hayashi M, Prentice DE. Successful drug development despite adverse preclinical findings part 2: examples. J Toxicol Pathol 2010; 23:213-34. [PMID: 22272032 PMCID: PMC3234630 DOI: 10.1293/tox.23.213] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 09/06/2010] [Indexed: 12/14/2022] Open
Abstract
To illustrate the process of addressing adverse preclinical findings (APFs) as
outlined in the first part of this review, a number of cases with unexpected APF
in toxicity studies with drug candidates is discussed in this second part. The
emphasis is on risk characterization, especially regarding the mode of action
(MoA), and risk evaluation regarding relevance for man. While severe APFs such
as retinal toxicity may turn out to be of little human relevance, minor findings
particularly in early toxicity studies, such as vasculitis, may later pose a
real problem. Rodents are imperfect models for endocrine APFs, non-rodents for
human cardiac effects. Liver and kidney toxicities are frequent, but they can
often be monitored in man and do not necessarily result in early termination of
drug candidates. Novel findings such as the unusual lesions in the
gastrointestinal tract and the bones presented in this review can be difficult
to explain. It will be shown that well known issues such as phospholipidosis and
carcinogenicity by agonists of peroxisome proliferator-activated receptors
(PPAR) need to be evaluated on a case-by-case basis. The latter is of particular
interest because the new PPAR α and dual α/γ agonists resulted in a change of
the safety paradigm established with the older PPAR α agonists. General
toxicologists and pathologists need some understanding of the principles of
genotoxicity and reproductive toxicity testing. Both types of preclinical
toxicities are major APF and clinical monitoring is difficult, generally leading
to permanent use restrictions.
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Affiliation(s)
- Robert A. Ettlin
- Ettlin Consulting Ltd., 14 Mittelweg, 4142 Muenchenstein,
Switzerland
| | - Junji Kuroda
- KISSEI Pharmaceutical Co., Ltd., 2320-1 Maki, Hotaka, Azumino,
Nagano 399-8305, Japan
| | - Stephanie Plassmann
- PreClinical Safety (PCS) Consultants Ltd., 7 Gartenstrasse, 4132
Muttenz, Switzerland
| | - Makoto Hayashi
- Biosafety Research Center, Foods, Drugs, and Pesticides (BSRC),
582-2 Shioshinden, Iwata, Shizuoka 437-1213, Japan
| | - David E. Prentice
- PreClinical Safety (PCS) Consultants Ltd., 7 Gartenstrasse, 4132
Muttenz, Switzerland
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12
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Ettlin RA, Kuroda J, Plassmann S, Prentice DE. Successful drug development despite adverse preclinical findings part 1: processes to address issues and most important findings. J Toxicol Pathol 2010; 23:189-211. [PMID: 22272031 PMCID: PMC3234634 DOI: 10.1293/tox.23.189] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 09/06/2010] [Indexed: 01/08/2023] Open
Abstract
Unexpected adverse preclinical findings (APFs) are not infrequently encountered during drug development. Such APFs can be functional disturbances such as QT prolongation, morphological toxicity or carcinogenicity. The latter is of particular concern in conjunction with equivocal genotoxicity results. The toxicologic pathologist plays an important role in recognizing these effects, in helping to characterize them, to evaluate their risk for man, and in proposing measures to mitigate the risk particularly in early clinical trials. A careful scientific evaluation is crucial while termination of the development of a potentially useful drug must be avoided. This first part of the review discusses processes to address unexpected APFs and provides an overview over typical APFs in particular classes of drugs. If the mode of action (MoA) by which a drug candidate produces an APF is known, this supports evaluation of its relevance for humans. Tailor-made mechanistic studies, when needed, must be planned carefully to test one or several hypotheses regarding the potential MoA and to provide further data for risk evaluation. Safety considerations are based on exposure at no-observed-adverse-effect levels (NOAEL) of the most sensitive and relevant animal species and guide dose escalation in clinical trials. The availability of early markers of toxicity for monitoring of humans adds further safety to clinical studies. Risk evaluation is concluded by a weight of evidence analysis (WoE) with an array of parameters including drug use, medical need and alternatives on the market. In the second part of this review relevant examples of APFs will be discussed in more detail.
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Affiliation(s)
- Robert A. Ettlin
- Ettlin Consulting Ltd., 14 Mittelweg, 4142 Muenchenstein,
Switzerland
| | - Junji Kuroda
- KISSEI Pharmaceutical Co., Ltd., 2320–1 Maki, Hotaka, Azumino,
Nagano 399-8305, Japan
| | - Stephanie Plassmann
- PreClinical Safety (PCS) Consultants Ltd., 7 Gartenstrasse, 4132
Muttenz, Switzerland
| | - David E. Prentice
- PreClinical Safety (PCS) Consultants Ltd., 7 Gartenstrasse, 4132
Muttenz, Switzerland
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14
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Weaver JL, Zhang J, Knapton A, Miller T, Espandiari P, Smith R, Gu YZ, Snyder RD. Early events in vascular injury in the rat induced by the phosphodiesterase IV inhibitor SCH 351591. Toxicol Pathol 2010; 38:738-44. [PMID: 20585143 DOI: 10.1177/0192623310374331] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Treatment with drugs from multiple classes induces vascular injury with medial necrosis, hemorrhage, endothelial damage, and inflammation. Previous research has suggested early events might be occurring well in advance of the full lesions that appear forty-eight to seventy-two hours after dosing with SCH 351591, a PDE IV inhibitor. This study was performed to study early events in detail. Rats were dosed with 20 mg/kg of drug by gavage and sacrificed at times between fifteen and 240 minutes after dosing. Tissues were collected for histopathological analysis and gene expression studies. Serum was collected for biomarker analysis. The data from biomarker analysis showed a three-part response with an early phase that was maximal at fifteen to thirty minutes, a second phase from forty-five to 180 minutes, and the third phase that was starting to rise at four hours. The first phase included increases in lymphocytes, serum histamine, and serum nitrite. The second phase shows continued elevation of serum nitrite. The third phase was marked by an increase in serum GRO/CINC-1. At fifteen minutes, histopathology showed activation of mast cells, but not degranulation. Increases in endothelial activation and perivascular inflammatory cells were first apparent at thirty minutes and increased through 240 minutes.
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Affiliation(s)
- James L Weaver
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993-0002, USA.
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15
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Banner KH, Press NJ. Dual PDE3/4 inhibitors as therapeutic agents for chronic obstructive pulmonary disease. Br J Pharmacol 2009; 157:892-906. [PMID: 19508401 DOI: 10.1111/j.1476-5381.2009.00170.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Phosphodiesterase (PDE)4, and to a lesser extent, PDE3/4 inhibitors have attracted considerable interest as potential therapeutic agents for diseases including chronic obstructive pulmonary disease. Indeed, ibudilast and theophylline are utilized clinically, and roflumilast is in late-stage clinical development. Unfortunately, however many PDE4 and dual PDE3/4 inhibitors have failed in early development due to low therapeutic ratios. The majority of these compounds are however orally administered and non-selective for either PDE3(A, B) or PDE4(A, B, C, D) subtypes. Developing an inhaled dual PDE3/4 inhibitor with subtype specificity may represent one strategy to improve the therapeutic index. Indeed combined inhibition of PDE3 and PDE4 inhibitor has additive and synergistic anti-inflammatory and bronchodilatory effects versus inhibition of either PDE3 or PDE4 alone. Given that synergy has been seen in terms of efficacy end points, an obvious concern is that synergy may also be observed in side effects. Interestingly, however, no synergy or additive effects with a combination of a PDE3 and PDE4 inhibitor in a cardiomyocyte assay were observed. This review will summarize the rationale for developing an inhaled dual PDE3/4 inhibitor, as a treatment for chronic obstructive pulmonary disease together with recent advances in trying to understand the pathogenesis of PDE inhibitor-induced mesenteric vasculitis (a key potential dose-limiting side effect of these agents), highlighting potential early and sensitive predictive biomarkers.
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Affiliation(s)
- Katharine H Banner
- Novartis Institute for Biomedical Research, Horsham, West Sussex, RH12 5AB, UK.
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16
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Weaver JL, Snyder R, Knapton A, Herman EH, Honchel R, Miller T, Espandiari P, Smith R, Gu YZ, Goodsaid FM, Rosenblum IY, Sistare FD, Zhang J, Hanig J. Biomarkers in Peripheral Blood Associated with Vascular Injury in Sprague-Dawley Rats Treated with the Phosphodiesterase IV Inhibitors SCH 351591 or SCH 534385. Toxicol Pathol 2008; 36:840-9. [DOI: 10.1177/0192623308322310] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Drug-associated vascular injury can be caused by phosphodiesterase (PDE) IV inhibitors and drugs from several other classes. The pathogenesis is poorly understood, but it appears to include vascular and innate immunological components. This research was undertaken to identify changes in peripheral blood associated with vascular injury caused by PDE IV inhibitors. We evaluated twelve proteins, serum nitrite, and leukocyte populations in peripheral blood of rats treated with experimental PDE IV inhibitors. We found that these compounds produced histological microvascular injury in a dose- and time-dependent manner. Measurement of these serum proteins showed changes in eight of the twelve examined. Changes were seen in the levels of: tissue inhibitor of metalloproteinase-1, α1-acid glycoprotein, GRO/CINC-1, vascular endothelial growth factor, C-reactive protein, haptoglobin, thrombomodulin, and interleukin-6. No changes were seen in levels of tumor necrosis factor-α, hepatocyte growth factor, nerve growth factor, and granulocyte-monocyte colony stimulating factor. Serum levels of nitrite were also increased. Circulating granulocyte numbers were increased, and lymphocyte numbers were decreased. The changes in these parameters showed both a dose- and time-dependent association with histopathologic changes. These biomarkers could provide an additional tool for the nonclinical and clinical evaluation of investigational compounds.
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Affiliation(s)
- James L. Weaver
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Ronald Snyder
- Schering-Plough Research Institute, Summit, New Jersey, USA
| | - Alan Knapton
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Eugene H. Herman
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Ronald Honchel
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Terry Miller
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Parvaneh Espandiari
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Roger Smith
- Schering-Plough Research Institute, Summit, New Jersey, USA
| | - Yi-Zhong Gu
- Schering-Plough Research Institute, Summit, New Jersey, USA
| | - Federico M. Goodsaid
- Office of Clinical Pharmacology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | | | | | - Jun Zhang
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Joseph Hanig
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
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17
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Hanton G, Sobry C, Daguès N, Provost JP, Le Net JL, Comby P, Chevalier S. Characterisation of the vascular and inflammatory lesions induced by the PDE4 inhibitor CI-1044 in the dog. Toxicol Lett 2008; 179:15-22. [DOI: 10.1016/j.toxlet.2008.03.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 03/04/2008] [Accepted: 03/04/2008] [Indexed: 01/28/2023]
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18
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Tesfamariam B, DeFelice AF. Endothelial injury in the initiation and progression of vascular disorders. Vascul Pharmacol 2006; 46:229-37. [PMID: 17218160 DOI: 10.1016/j.vph.2006.11.005] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Accepted: 11/27/2006] [Indexed: 01/23/2023]
Abstract
Endothelial cell dysfunction is considered to be an early event which subsequently leads to vascular wall disorders. Ultrastructural studies indicate that the endothelial cell changes involve membrane damage, increased permeability, swelling and necrosis. The endothelial cell loss of function could be as a result of changes in hemodynamic forces (shear and/or hoop stress), direct drug-induced cytotoxicity, mechanical device implant-induced injury and/or immune-mediated mechanisms. Drugs may perturb endothelial cell integrity by directly triggering inflammatory signaling cascades, enhancing expression of cellular adhesion molecules, activation of cytotoxic T cells and/or autoantibodies directed against endothelial cell membranes. Local release of inflammatory cytokines and chemokines activate endothelial cells to upregulate soluble adhesion molecules, activate neutrophils and generate reactive oxygen species which serve to amplify the initial inflammation leading to dysregulated apoptosis, secondary necrosis and overt vascular injury lesions. Considering the role of the endothelium in the initiation and propagation of vascular wall injury, there is a need for the discovery of validated biomarkers to serve as a predictor of activation of inflammatory cascades in the development of vascular injury. This article reviews some aspects of the multifaceted mechanisms that lead to the initial endothelial cell disruption and subsequent vascular wall injury.
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Affiliation(s)
- Belay Tesfamariam
- Division of Cardiovascular and Renal Products, Center for Drug Evaluation and Research, FDA, Bldg 22, Rm 4176, 10903 New Hampshire Ave, Silver Spring, MD 20993-0002, USA.
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19
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Zhang J, Herman EH, Robertson DG, Reily MD, Knapton A, Ratajczak HV, Rifai N, Honchel R, Blanchard KT, Stoll RE, Sistare FD. Mechanisms and biomarkers of cardiovascular injury induced by phosphodiesterase inhibitor III SK&F 95654 in the spontaneously hypertensive rat. Toxicol Pathol 2006; 34:152-63. [PMID: 16537294 DOI: 10.1080/01926230600588562] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The cardiovascular injury of the type III selective PDE inhibitor SK&F 95654 was investigated in SHR. Twenty-four hours after a single sc injection of 100 or 200 mg/kg of the drug, rats exhibited cardiomyocyte necrosis and apoptosis, interstitial inflammation, hemorrhage and edema, as well as mesenteric arterial hemorrhage and necrosis, periarteritis, EC and VSMC apoptosis, EC activation, and MC activation and degranulation. Elevated serum levels of cTnT and decreased cTnT immunoperoxidase staining on cardiomyocytes were detected in the drug-treated rats. Serum levels of alpha2-macroglobulin and IL-6 were significantly elevated following drug treatment. NMR spectral patterns of urine samples are significantly different between the drug-treated and control rats. These results indicate that measurement of serum cTnT, acute phase proteins, and cytokines as well as metabonomic urine profiles may serve as potential biomarkers for drug-induced cardiovascular injury in rats. Increased expression of CD63 on MC (tissue biomarker of MC), of nitrotyrosine on MC and EC (an indirect indicator of NO in vivo), and of iNOS on MC and EC (source of NO) suggest that NO produced by activated and degranulated MC as well as activated EC play an important role in SK&F 95654-induced mesenteric vascular injury.
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Affiliation(s)
- Jun Zhang
- Division of Applied Pharmacology Research (HFD-910), Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, USA.
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20
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Louden C, Brott D, Katein A, Kelly T, Gould S, Jones H, Betton G, Valetin JP, Richardson RJ. Biomarkers and mechanisms of drug-induced vascular injury in non-rodents. Toxicol Pathol 2006; 34:19-26. [PMID: 16507540 DOI: 10.1080/01926230500512076] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In preclinical safety studies, drug-induced vascular injury can negatively impact candidate-drug selection because there are no obvious diagnostic markers for monitoring this pathology preclinically or clinically. Furthermore, our current understanding of the pathogenesis of this lesion is limited. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary target cells, smooth muscle (SMC) and endothelial cell (EC), are unknown. Evaluation of potential novel markers for clinical monitoring with a mechanistic underpinning would add value in risk assessment and risk management. This mini review focuses on the efforts and progress to identify diagnostic markers as well as understanding the mechanism of action in nonrodent drug-induced vascular injury.
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MESH Headings
- Animals
- Biomarkers/analysis
- Biomarkers/metabolism
- Dogs
- Drug Evaluation, Preclinical
- Drugs, Investigational/adverse effects
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Nitric Oxide/analysis
- Nitric Oxide/metabolism
- Vascular Diseases/chemically induced
- Vascular Diseases/metabolism
- Vascular Diseases/pathology
- von Willebrand Factor/analysis
- von Willebrand Factor/metabolism
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Affiliation(s)
- Calvert Louden
- Department of Safety Assessment, AstraZeneca Pharmaceuticals, Cheshire, UK.
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21
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Dietsch GN, Dipalma CR, Eyre RJ, Pham TQ, Poole KM, Pefaur NB, Welch WD, Trueblood E, Kerns WD, Kanaly ST. Characterization of the inflammatory response to a highly selective PDE4 inhibitor in the rat and the identification of biomarkers that correlate with toxicity. Toxicol Pathol 2006; 34:39-51. [PMID: 16507543 DOI: 10.1080/01926230500385549] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The primary toxicity associated with repeated oral administration of the PDE4 inhibitor IC542 to the rat is an inflammatory response leading to tissue damage primarily in the gastrointestinal tract and mesentery. Although necrotizing vasculitis is frequently seen with other PDE4 inhibitors, blood vessel injury was rare following IC542 administration and was always associated with inflammation in the surrounding tissue. The incidence and severity of the histologic changes in these studies correlated with elevated peripheral blood leukocytes, serum IL-6, haptoglobin, and fibrinogen, and with decreased serum albumin. By monitoring haptoglobin, fibrinogen and serum albumin changes in IC542-treated rats, it was possible to identify rats with early histologic changes that were reversible. Since PDE4 inhibition is generally associated with anti-inflammatory activity, extensive inflammation in multiple tissues was unexpected with IC542. Co-administration of dexamethasone completely blocked IC542-induced clinical and histologic changes in the rat, confirming the toxicity resulted from inflammatory response. In addition, IC542 augmented release of the proinflammatory cytokine IL-6 in LPS-activated whole blood from rats but not monkeys or humans. The effect of IC542 on IL-6 release from rat leukocytes in vitro is consistent with the proinflammatory response observed in vivo and demonstrates species differences to PDE4 inhibition.
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22
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Kerns W, Schwartz L, Blanchard K, Burchiel S, Essayan D, Fung E, Johnson R, Lawton M, Louden C, MacGregor J, Miller F, Nagarkatti P, Robertson D, Snyder P, Thomas H, Wagner B, Ward A, Zhang J. Drug-induced vascular injury—a quest for biomarkers. Toxicol Appl Pharmacol 2005; 203:62-87. [PMID: 15694465 DOI: 10.1016/j.taap.2004.08.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Accepted: 08/02/2004] [Indexed: 11/23/2022]
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23
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Bian H, Zhang J, Wu P, Varty LA, Jia Y, Mayhood T, Hey JA, Wang P. Differential type 4 cAMP-specific phosphodiesterase (PDE4) expression and functional sensitivity to PDE4 inhibitors among rats, monkeys and humans. Biochem Pharmacol 2004; 68:2229-36. [PMID: 15498513 DOI: 10.1016/j.bcp.2004.08.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2004] [Accepted: 08/09/2004] [Indexed: 10/26/2022]
Abstract
It has been suggested that the rat is relatively more susceptible to toxicity induced by inhibitors for type 4 cAMP-specific phosphodiesterase (PDE4). In this study designed to elucidate possible biochemical basis for the higher susceptibility, we compared PDE4 expression levels and their functional relevance among rats, monkeys and humans. In several toxicologically relevant tissues and blood leukocytes, the mRNA expression levels of PDEs 4A, 4B, 4C and 4D were significantly higher in rats than in humans. We confirmed that higher PDE4 expression levels were correlated with a higher enzyme activity level in rat leukocytes. The PDE4 enzyme activity level of leukocytes in monkeys fell between that of rats and humans. Functionally, the potencies of the PDE4 inhibitors rolipram, SB 207499 and SCH 351591 in inhibiting tumor necrosis factor production from leukocytes were in the following order: rat > monkey > human. In addition, rolipram was about 10-fold more potent in rats than in humans in inhibiting phenylephrine-induced contraction of renal artery. These inhibitors were confirmed to be highly selective for PDE4 in comparison to all other PDE families, and to inhibit rat and human PDE4s with identical potencies. Taken together, these results suggest that the higher susceptibility of rats to PDE4 inhibitor-induced toxicity might be due to their higher expression levels of PDE4, and that PDE4 inhibitors may be safer in humans than in monkeys and, particularly, rats.
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Affiliation(s)
- Hong Bian
- Schering-Plough Research Institute, Kenilworth, NJ 07033, USA
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