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Bacevich BM, Smith RDJ, Reihl AM, Mazzocca AD, Hutchinson ID. Advances with Platelet-Rich Plasma for Bone Healing. Biologics 2024; 18:29-59. [PMID: 38299120 PMCID: PMC10827634 DOI: 10.2147/btt.s290341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/17/2024] [Indexed: 02/02/2024]
Abstract
Despite significant advances in the understanding and delivery of osteosynthesis, fracture non-union remains a challenging clinical problem in orthopaedic surgery. To bridge the gap, basic science characterization of fracture healing provides a platform to identify and target biological strategies to enhance fracture healing. Of immense interest, Platelet-rich plasma (PRP) is a point of care orthobiologic that has been extensively studied in bone and soft tissue healing given its relative ease of translation from the benchtop to the clinic. The aim of this narrative review is to describe and relate pre-clinical in-vitro and in-vivo findings to clinical observations investigating the efficacy of PRP to enhance bone healing for primary fracture management and non-union treatment. A particular emphasis is placed on the heterogeneity of PRP preparation techniques, composition, activation strategies, and delivery. In the context of existing data, the routine use of PRP to enhance primary fracture healing and non-union management cannot be supported. However, it is acknowledged that extensive heterogeneity of PRP treatments in clinical studies adds obscurity; ultimately, refinement (and consensus) of PRP treatments for specific clinical indications, including repetition studies are warranted.
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Affiliation(s)
- Blake M Bacevich
- Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Brigham, Boston, MA, USA
| | - Richard David James Smith
- Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Brigham, Boston, MA, USA
| | - Alec M Reihl
- Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Brigham, Boston, MA, USA
| | - Augustus D Mazzocca
- Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Brigham, Boston, MA, USA
- Medical Director, Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Brigham, Boston, MA, USA
| | - Ian D Hutchinson
- Division of Sports Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Massachusetts General Brigham, Boston, MA, USA
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Li B, Chen C, Jia J, He L. Research progress on antineoplastic, antibacterial, and anti-inflammatory activities of seven-membered heterocyclic derivatives. Curr Med Chem 2022; 29:5076-5096. [PMID: 35345989 DOI: 10.2174/0929867329666220328123953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/20/2021] [Accepted: 12/30/2021] [Indexed: 11/22/2022]
Abstract
Abstract:
Seven-membered heterocyclic compounds are important drug scaffolds, because of their unique chemical structures. They widely exist in natural products and show a variety of biological activities. They have commonly been used in central nervous system drugs in the past 30 years. In the past decade, there are many studies on the activities of antitumor, antibacterial, etc. Herein, we summarize the research advances in different kinds of seven-membered heterocyclic compounds containing nitrogen, oxygen, and sulfur heteroatoms with antitumor, antisepsis, and anti-inflammation activities in the past ten years, which is expected to be beneficial to the development and design of novel drugs for the corresponding indications.
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Affiliation(s)
- Bin Li
- Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Chen Chen
- Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Jingjing Jia
- Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ling He
- Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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Liu XG, Lu X, Gao W, Li P, Yang H. Structure, synthesis, biosynthesis, and activity of the characteristic compounds from Ginkgo biloba L. Nat Prod Rep 2021; 39:474-511. [PMID: 34581387 DOI: 10.1039/d1np00026h] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Covering: 1928-2021Ginkgo biloba L. is one of the most distinctive plants to have emerged on earth and has no close living relatives. Owing to its phylogenetic divergence from other plants, G. biloba contains many compounds with unique structures that have served to broaden the chemical diversity of herbal medicine. Examples of such compounds include terpene trilactones (ginkgolides), acylated flavonol glycosides (ginkgoghrelins), biflavones (ginkgetin), ginkgotides and ginkgolic acids. The extract of G. biloba leaf is used to prevent and/or treat cardiovascular diseases, while many ginkgo-derived compounds are currently at various stages of preclinical and clinical trials worldwide. The global annual sales of G. biloba products are estimated to total US$10 billion. However, the content and purity of the active compounds isolated by traditional methods are usually low and subject to varying environmental factors, making it difficult to meet the huge demand of the international market. This highlights the need to develop new strategies for the preparation of these characteristic compounds from G. biloba. In this review, we provide a detailed description of the structures and bioactivities of these compounds and summarize the recent research on the development of strategies for the synthesis, biosynthesis, and biotechnological production of the characteristic terpenoids, flavonoids, and alkylphenols/alkylphenolic acids of G. biloba. Our aim is to provide an important point of reference for all scientists who research ginkgo-related compounds for medicinal or other purposes.
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Affiliation(s)
- Xin-Guang Liu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, #24 Tong Jia Xiang, Nanjing 210009, China.
| | - Xu Lu
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, #24 Tong Jia Xiang, Nanjing 210009, China.
| | - Wen Gao
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, #24 Tong Jia Xiang, Nanjing 210009, China.
| | - Ping Li
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, #24 Tong Jia Xiang, Nanjing 210009, China.
| | - Hua Yang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, #24 Tong Jia Xiang, Nanjing 210009, China.
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Smal MA, Baldo BA. Inhibition of platelet-activating factor (PAF)-induced platelet aggregation by fatty acids from human saliva. Platelets 2021; 33:562-569. [PMID: 34348059 DOI: 10.1080/09537104.2021.1961705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Experiments were undertaken to identify the nature of a previously identified inhibitor of PAF-induced platelet aggregation (PA) in human saliva. Human saliva fractionated by preparative thin layer chromatography (TLC) yielded a fraction that co-migrated with fatty acids (FAs) and inhibited PAF-induced aggregation of platelets. Synthetic FAs tested for their capacities to inhibit 0.1 nM PAF-induced PA showed that only the cis-unsaturated compounds were inhibitory with activities of some of the polyunsaturated FAs (PUFA) reaching almost 100% at 20 μM. Eicosapentanoic acid (EPA) and 8,11,14-eicosatrienoic acid also deaggregated the PAF-induced aggregates. With the exception of oleic acid (OLA), cis-monounsaturated FAs, and elaidic acid, the trans isomer of OLA, were poor inhibitors. In a direct comparison with other platelet agonists, ADP, thrombin, and ionophore A23187, the active saliva fraction and selected individual (FA) inhibited, to greater or lesser extent, PA induced by each of the agonists. EPA, OLA, linoleic acid (LNA), and the active saliva fraction were potent inhibitors of ADP-induced PA, EPA completely inhibited thrombin-induced PA and the saliva fraction showed only weak - moderate inhibitory activity to both thrombin- and ionophore A23187-induced PA. Other reports of endogenous PAF inhibitors in mammalian tissues are compared to the present results. PAF can trigger and amplify inflammatory cascades suggesting a possible modulation role for cis-unsaturated FAs in some diseases.
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Affiliation(s)
- Mary A Smal
- Kolling Institute of Medical Research, Royal North Shore Hospital of Sydney, St Leonards
| | - Brian A Baldo
- Kolling Institute of Medical Research, Royal North Shore Hospital of Sydney, St Leonards.,Department of Medicine, University of Sydney, NSW, Australia
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Abstract
The application of ginkgolides as a herbal remedy reaches ancient China. Over time many studies confirmed the neuroprotective effect of standard Ginkgo biloba tree extract—the only available ginkgolide source. Ginkgolides present a wide variety of neuroregulatory properties, commonly used in the therapy process of common diseases, such as Alzheimer’s, Parkinson’s, and many other CNS-related diseases and disorders. The neuroregulative properties of ginkgolides include the conditioning of neurotransmitters action, e.g., glutamate or dopamine. Besides, natural compounds induce the inhibition of platelet-activating factors (PAF). Furthermore, ginkgolides influence the inflammatory process. This review focuses on the role of ginkgolides as neurotransmitters or neuromodulators and overviews their impact on the organism at the molecular, cellular, and physiological levels. The clinical application of ginkgolides is discussed as well.
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Quiroga J, Alarcón P, Manosalva C, Taubert A, Hermosilla C, Hidalgo MA, Carretta MD, Burgos RA. Mitochondria-derived ATP participates in the formation of neutrophil extracellular traps induced by platelet-activating factor through purinergic signaling in cows. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 113:103768. [PMID: 32692996 DOI: 10.1016/j.dci.2020.103768] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/28/2020] [Accepted: 06/06/2020] [Indexed: 06/11/2023]
Abstract
Neutrophil extracellular trap (NET) formation eliminates/prevents the spread of infectious agents. Platelet activating factor (PAF) is involved in infectious diseases of cattle because it recruits and activates neutrophils. However, its ability to induce NET release and the role of metabolism in this process is not known. We investigated if inhibition of glycolysis, mitochondrial-derived adenosine triphosphate (ATP) synthesis and purinergic signaling though P2X1 purinoceptors interfered with NET formation induced by PAF. We inhibited bovine neutrophils with 2-deoxy-d-glucose, rotenone, carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and NF449 to evaluate PAF-mediated NET extrusion. PAF induced mitochondrial hyperpolarization and triggered extracellular ATP release via pannexin-1. Inhibition of mitochondrial metabolism prevented extracellular ATP release. Inhibition of glycolysis, complex-I activity and oxidative phosphorylation prevented NET formation induced by PAF. Inhibition of P2X1 purinergic receptors inhibited mitochondrial hyperpolarization and NET formation. We concluded that PAF-induced NET release is dependent upon glycolysis, mitochondrial ATP synthesis and purinergic signaling.
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Affiliation(s)
- John Quiroga
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Immunometabolism, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Pablo Alarcón
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Immunometabolism, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Carolina Manosalva
- Institute of Pharmacy, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Anja Taubert
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - Carlos Hermosilla
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - María Angélica Hidalgo
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Immunometabolism, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - María Daniella Carretta
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Immunometabolism, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Rafael Agustín Burgos
- Laboratory of Inflammation Pharmacology, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Immunometabolism, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile.
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Khiyani MF, Ahmadi M, Barbeau J, Feine JS, de Souza RF, Siqueira WL, Emami E. Salivary Biomarkers in Denture Stomatitis: A Systematic Review. JDR Clin Trans Res 2019; 4:312-322. [PMID: 30931724 DOI: 10.1177/2380084419830941] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVE Denture stomatitis (DS) is an oral biofilm-associated inflammation of the denture-bearing mucosa. The objective of this review was to identify and evaluate the quality of evidence on the association between the levels of salivary biomarkers and DS among adults with and without palatal DS. MATERIALS AND METHODS Following the PRISMA guidelines, Medline, PubMed, EMBASE, and the Cochrane Central Register for Controlled Trials were searched for eligible studies from the beginning of the archives until December 2018. Experimental and observational studies with adult participants were included that had a control group or subgroup analysis and provided data on salivary biomarkers and DS. Articles in languages other than English or French were excluded. The level of evidence and grades of recommendation were established with the 2011 scale of the Oxford Centre for Evidence-Based Medicine. Additionally, the assessment of methodological quality was conducted with the STROBE statement (Strengthening the Reporting of Observational Studies in Epidemiology) and graded according to the Olmos scale. RESULTS From 1,008 citations, 9 studies were included in the systematic review (8 observational, 1 clinical trial). Seven studies suggested a statistically significant difference in the levels of salivary cytokines (IL-6, CCL3, TGF-β, CXCL8, GM-CSF, and TNF-α) between participants with DS and controls (P < 0.05). In contrast, 2 studies concluded that the difference in the levels of several salivary cytokines (IL2, IL12, IFN-g, IL-4, IL-8, IL-10, IL-17, TNF-α, and ICAM-1) between the groups was not statistically significant. The level of evidence for the majority of studies was 3, while the grade of recommendation for all the studies was B, interpreted as "favorable." In terms of methodological quality, most studies met 50% to 80% of STROBE criteria and were graded B. CONCLUSION Palatal inflammation in DS is significantly associated with the levels of salivary cytokines. KNOWLEDGE TRANSFER STATEMENT The results of this study identified altered levels of specific salivary biomarkers associated with denture stomatitis, which may aid in the early diagnosis and treatment of this disease.
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Affiliation(s)
- M F Khiyani
- Faculty of Dental Medicine, Université de Montréal, Montreal, QC, Canada
| | - M Ahmadi
- Faculty of Dental Medicine, Université de Montréal, Montreal, QC, Canada
| | - J Barbeau
- Faculty of Dental Medicine, Université de Montréal, Montreal, QC, Canada
| | - J S Feine
- Faculty of Dentistry, McGill University, Montréal, QC, Canada
| | - R F de Souza
- Faculty of Dentistry, McGill University, Montréal, QC, Canada
| | - W L Siqueira
- Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, Canada
| | - E Emami
- Faculty of Dental Medicine, Université de Montréal, Montreal, QC, Canada.,Faculty of Dentistry, McGill University, Montréal, QC, Canada
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Hyland IK, O'Toole RF, Smith JA, Bissember AC. Progress in the Development of Platelet-Activating Factor Receptor (PAFr) Antagonists and Applications in the Treatment of Inflammatory Diseases. ChemMedChem 2018; 13:1873-1884. [DOI: 10.1002/cmdc.201800401] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/08/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Isabel K. Hyland
- School of Natural Sciences Chemistry; University of Tasmania; Hobart Australia
| | | | - Jason A. Smith
- School of Natural Sciences Chemistry; University of Tasmania; Hobart Australia
| | - Alex C. Bissember
- School of Natural Sciences Chemistry; University of Tasmania; Hobart Australia
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Tsoupras A, Lordan R, Zabetakis I. Inflammation, not Cholesterol, Is a Cause of Chronic Disease. Nutrients 2018; 10:E604. [PMID: 29757226 PMCID: PMC5986484 DOI: 10.3390/nu10050604] [Citation(s) in RCA: 161] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 05/03/2018] [Accepted: 05/09/2018] [Indexed: 12/17/2022] Open
Abstract
Since the Seven Countries Study, dietary cholesterol and the levels of serum cholesterol in relation to the development of chronic diseases have been somewhat demonised. However, the principles of the Mediterranean diet and relevant data linked to the examples of people living in the five blue zones demonstrate that the key to longevity and the prevention of chronic disease development is not the reduction of dietary or serum cholesterol but the control of systemic inflammation. In this review, we present all the relevant data that supports the view that it is inflammation induced by several factors, such as platelet-activating factor (PAF), that leads to the onset of cardiovascular diseases (CVD) rather than serum cholesterol. The key to reducing the incidence of CVD is to control the activities of PAF and other inflammatory mediators via diet, exercise, and healthy lifestyle choices. The relevant studies and data supporting these views are discussed in this review.
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Affiliation(s)
- Alexandros Tsoupras
- Department of Biological Sciences, University of Limerick, V94 T9PX Limerick, Ireland.
| | - Ronan Lordan
- Department of Biological Sciences, University of Limerick, V94 T9PX Limerick, Ireland.
| | - Ioannis Zabetakis
- Department of Biological Sciences, University of Limerick, V94 T9PX Limerick, Ireland.
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Brousseau-Nault M, Kizhakkedathu JN, Kim H. Chronic periodontitis is associated with platelet factor 4 (PF4) secretion: A pilot study. J Clin Periodontol 2017; 44:1101-1111. [DOI: 10.1111/jcpe.12771] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/02/2017] [Indexed: 01/22/2023]
Affiliation(s)
- Mathieu Brousseau-Nault
- Faculty of Dentistry; University of British Columbia; Vancouver BC Canada
- Centre for Blood Research; University of British Columbia; Vancouver BC Canada
| | - Jayachandran N. Kizhakkedathu
- Centre for Blood Research; University of British Columbia; Vancouver BC Canada
- Department of Pathology and Laboratory Medicine; University of British Columbia; Vancouver BC Canada
- Department of Chemistry; University of British Columbia; Vancouver BC Canada
| | - Hugh Kim
- Faculty of Dentistry; University of British Columbia; Vancouver BC Canada
- Centre for Blood Research; University of British Columbia; Vancouver BC Canada
- Department of Biochemistry and Molecular Biology; University of British Columbia; Vancouver BC Canada
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11
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Moschos MM, Nitoda E, Chatziralli IP, Panos GD, Demopoulos CA. Impact of prostaglandin glaucoma drops on platelet-activating factor action: an in vitro study. Drug Des Devel Ther 2016; 10:3977-3981. [PMID: 27994439 PMCID: PMC5153256 DOI: 10.2147/dddt.s117806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/30/2022] Open
Abstract
AIM The aim of this study was to investigate the effect of different prostaglandin analogs on platelet-activating factor (PAF) levels. METHODS Three prostaglandin analogs were selected: bimatoprost 0.3 mg/mL, latanoprost 50 μg/mL, and tafluprost 15 μg/mL. Each drug sample was tested for its ability to cause platelet aggregation, which was measured as PAF-induced aggregation, before and after the addition of various concentrations of the examined sample, creating a linear curve of percentage inhibition (ranging from 0% to 100%) versus different concentrations of the sample. The concentration of the sample that inhibited 50% PAF-induced aggregation was calculated based on this curve, and this value was defined as IC50. In addition, the effect of eye drops on PAF metabolism was examined, through an in vitro analysis on PAF basic metabolic enzymes (PAF-cholinephosphotransferase, PAF-acetyl-CoA:1-O-alkyl-sn-glycero-3-phosphocholine acetyltransferase, and PAF-acetylhydrolase). RESULTS The IC50 values for Lumigan UD® (bimatoprost 0.3 mg/mL), Monoprost® (latanoprost 50 μg/mL), and Saflutan (tafluprost 15 μg/mL) were 8.7, 0.28, and 1.4 μg/mL, respectively. DISCUSSION All three prostaglandin analogs suspended PAF, but bimatoprost induced the most potent inhibition, compared to tafluprost and to the weak effect of latanoprost.
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Affiliation(s)
- Marilita M Moschos
- 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Eirini Nitoda
- 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Irini P Chatziralli
- 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Georgios D Panos
- Department of Ophthalmology, Geneva University Hospitals (HUG), University of Geneva, Geneva, Switzerland
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Ji S, Choi Y. Point-of-care diagnosis of periodontitis using saliva: technically feasible but still a challenge. Front Cell Infect Microbiol 2015; 5:65. [PMID: 26389079 PMCID: PMC4558535 DOI: 10.3389/fcimb.2015.00065] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/21/2015] [Indexed: 12/14/2022] Open
Abstract
Periodontitis is a chronic inflammation of the periodontium caused by persistent bacterial infection that leads to the breakdown of connective tissue and bone. Because the ability to reconstruct the periodontium is limited after alveolar bone loss, early diagnosis and intervention should be the primary goals of periodontal treatment. However, periodontitis often progresses without noticeable symptoms, and many patients do not seek professional dental care until the periodontal destruction progresses to the point of no return. Furthermore, the current diagnosis of periodontitis depends on time-consuming clinical measurements. Therefore, there is an unmet need for near-patient testing to diagnose periodontitis. Saliva is an optimal biological fluid to serve as a near-patient diagnostic tool for periodontitis. Recent developments in point-of-care (POC) testing indicate that a diagnostic test for periodontitis using saliva is now technically feasible. A number of promising salivary biomarkers associated with periodontitis have been reported. A panel of optimal biomarkers must be carefully selected based on the pathogenesis of periodontitis. The biggest hurdle for the POC diagnosis of periodontitis using saliva may be the process of validation in a large, diverse patient population. Therefore, we propose the organization of an International Consortium for Biomarkers of Periodontitis, which will gather efforts to identify, select, and validate salivary biomarkers for the diagnosis of periodontitis.
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Affiliation(s)
- Suk Ji
- Department of Periodontology, Anam Hospital, Korea University Seoul, South Korea
| | - Youngnim Choi
- Department of Oral Microbiology and Immunology, School of Dentistry and Dental Research Institute, Seoul National University Seoul, South Korea
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Mechanism by which nuclear factor-kappa beta (NF-kB) regulates ovine fetal pulmonary vascular smooth muscle cell proliferation. Mol Genet Metab Rep 2015; 4:11-8. [PMID: 26966681 PMCID: PMC4777924 DOI: 10.1016/j.ymgmr.2015.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Platelet activating factor (PAF) modulates ovine fetal pulmonary hemodynamic. PAF acts through its receptors (PAFR) in pulmonary vascular smooth muscle cells (PVSMC) to phosphorylate and induce nuclear translocation of NF-kB p65 leading to PVSMC proliferation. However, the interaction of NF-kB p65 and PAF in the nuclear domain to effect PVSMC cell growth is not clearly defined. We used siRNA-dependent translation initiation arrest to study a mechanism by which NF-kB p65 regulates PAF stimulation of PVSMC proliferation. Our hypotheses are: (a) PAF induces NF-kB p65 DNA binding and (b) NF-kB p65 siRNA attenuates PAF stimulation of PVSMC proliferation. For DNA binding, cells were fed 10 nM PAF with and without PAFR antagonists WEB 2170, CV 3988 or BN 52021 and incubated for 12 h. DNA binding was measured by specific ELISA. For NF-kB p65 siRNA effect, starved cells transfected with the siRNA were incubated for 24 h with and without 10 nM PAF. Cell proliferation was measured by DNA synthesis while expression of NF-kB p65 and PAFR protein was measured by Western blotting. In both studies, the effect of 10% FBS alone was used as the positive control. In general, PAF stimulated DNA binding which was inhibited by PAFR antagonists. siRNAs to NF-kB p65 and PAFR significantly attenuated cell proliferation compared to 10% FBS and PAF effect. Inclusion of PAF in siRNA-treated cells did not reverse inhibitory effect of NF-kB p65 siRNA on DNA synthesis. PAFR expression was inhibited in siRNA-treated cells. These data show that PAF-stimulation of PVSMC proliferation occurs via a PAFR-NF-kB p65 linked pathway.
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Nitoda E, Koutsilieris M, Brouzas D, Koutsandrea C, Philippou A, Ladas D, Moschos MM. Correlation of platelet activating factor and age-related macular degeneration. Expert Opin Ther Targets 2014; 18:987-97. [PMID: 25077601 DOI: 10.1517/14728222.2014.930439] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the role of Platelet Activating Factor (PAF) in the pathogenesis and development of Age-Related Macular Degeneration (ARMD). RESEARCH DESIGN AND METHODS Fifty six patients with ARMD (24 patients with dry ARMD and 32 patients with wet ARMD) and 25 age-matched control participants underwent ophthalmological examination, including visual acuity measurement and evaluation of the retina. The participants were classified into three groups according to their retinal status, based on indirect fundoscopy, Optical Coherence Tomography and fluorescein angiography findings. In order to evaluate the concentrations of PAF in serum, blood samples were collected from all participants and were analyzed with ELISA technique. RESULTS The concentrations of PAF differed significantly according to macular lesions and were found to be lower in patients with ARMD than control participants. CONCLUSIONS PAF levels are decreased along with the severity of ARMD. Understanding the role of PAF in pathogenesis of ARMD could be the impetus for the development of new therapies field of treatment of ARMD or even other retinal diseases.
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Affiliation(s)
- Eirini Nitoda
- National and Kapodistrian University of Athens, 1st Department of Ophthalmology, Medical School , Athens , Greece +306944887319 ; +302104122319 ;
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Johnston LK, Chien KB, Bryce PJ. The immunology of food allergy. THE JOURNAL OF IMMUNOLOGY 2014; 192:2529-34. [PMID: 24610821 DOI: 10.4049/jimmunol.1303026] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Food allergies represent an increasingly prevalent human health problem, and therapeutic options remain limited, with avoidance being mainstay, despite its adverse effects on quality of life. A better understanding of the key immunological mechanisms involved in such responses likely will be vital for development of new therapies. This review outlines the current understanding of how the immune system is thought to contribute to prevention or development of food allergies. Drawing from animal studies, as well as clinical data when available, the importance of oral tolerance in sustaining immunological nonresponsiveness to food Ags, our current understanding of why oral tolerance may fail and sensitization may occur, and the knowledge of pathways that may lead to anaphylaxis and food allergy-associated responses are addressed.
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Affiliation(s)
- Laura K Johnston
- Division of Allergy-Immunology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago IL 60611
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Flasiński M, Hąc-Wydro K, Wydro P, Dynarowicz-Łątka P. Influence of platelet-activating factor, lyso-platelet-activating factor and edelfosine on Langmuir monolayers imitating plasma membranes of cell lines differing in susceptibility to anti-cancer treatment: the effect of plasmalogen level. J R Soc Interface 2014; 11:20131103. [PMID: 24694892 DOI: 10.1098/rsif.2013.1103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Three structurally related but differing in biological activities single-chained ether phospholipids (PAF (platelet-activating factor) and lyso-PAF) and an anti-cancer drug (edelfosine (ED)) were investigated in Langmuir monolayers imitating natural membranes. The aim of the undertaken experiments was to study the influence of these lipids on monolayers mimicking plasma membranes of cell lines differing in susceptibility to the anti-cancer activity of ED, i.e. promyelocytic leukaemia cells (HL-60) and promyeloblastic leukaemia cells (K-562). As these cells differ essentially in the cholesterol/phospholipid ratio and plasmalogen concentration in the membrane, we have carried out systematic investigations in artificial systems of various compositions. The results for model leukaemia cell membrane were compared with data acquired for systems imitating normal leucocytes. Our results show that the level of plasmalogens significantly modulates the influence of the single-chained phospholipids on the investigated systems. The experiments confirmed also that the interactions of ether lipids with a model membrane of HL-60 cells (in biological tests sensitive to ED) have opposite character when compared with K-562, being resistant to ED. Moreover, the values of the parameters characterizing monolayers serving as membrane models (strength of interactions, monolayers fluidity and morphology) proved both sensitivity of these cells to ED and lack of their susceptibility towards PAF. Interestingly, it has been found that lyso-PAF, which is usually described as an inactive precursor of PAF, displays a stronger effect on HL-60 model membranes than ED.
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Affiliation(s)
- Michał Flasiński
- Faculty of Chemistry, Department of Environmental Chemistry, Jagiellonian University, , Gronostajowa 3, 30-387 Kraków, Poland
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Age-Related Macular Degeneration: Pathogenesis, Genetic Background, and the Role of Nutritional Supplements. J CHEM-NY 2014. [DOI: 10.1155/2014/317536] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Age-related macular degeneration (ARMD) is the leading cause of severe vision loss and blindness worldwide, mainly affecting people over 65 years old. Dry and wet ARDM are the main types of the disease, which seem to have a multifactorial background. The aim of this review is to summarize the mechanisms of ARMD pathogenesis and exhibit the role of diet and nutritional supplements in the onset and progression of the disease. Environmental factors, such as smoking, alcohol, and, diet appear to interact with mutations in nuclear and mitochondrial DNA, contributing to the pathogenesis of ARMD. Inflammatory mediators and oxidative stress, induced by the daily exposure of retina to high pressure of oxygen and light radiation, have been also associated with ARMD lesions. Other than medical and surgical therapies, nutritional supplements hold a significant role in the prevention and treatment of ARMD, eliminating the progression of macular degeneration.
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Interactions between single-chained ether phospholipids and sphingomyelin in mixed monolayers at the air/water interface—Grazing incidence X-ray diffraction and Brewster angle microscopy studies. Colloids Surf B Biointerfaces 2013; 111:43-51. [DOI: 10.1016/j.colsurfb.2013.05.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 05/12/2013] [Accepted: 05/15/2013] [Indexed: 11/19/2022]
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Renteria LS, Austin M, Lazaro M, Andrews MA, Lustina J, Raj JU, Ibe BO. RhoA-Rho kinase and platelet-activating factor stimulation of ovine foetal pulmonary vascular smooth muscle cell proliferation. Cell Prolif 2013; 46:563-75. [PMID: 24033386 PMCID: PMC3788060 DOI: 10.1111/cpr.12052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 05/17/2013] [Indexed: 01/02/2023] Open
Abstract
OBJECTIVES Platelet-activating factor (PAF) is produced by pulmonary vascular smooth muscle cells (PVSMC). We studied effects of Rho kinase on PAF stimulation of PVSMC proliferation in an attempt to understand the role of RhoA/Rho kinase on PAF-induced ovine foetal pulmonary vascular remodelling. Our hypothesis is that PAF acts through Rho kinase, as one of its downstream signals, to induce arterial (SMC-PA) and venous (SMC-PV) cell proliferation in the hypoxic lung environment of the foetus, in utero. MATERIALS AND METHODS Rho kinase and MAPK effects on PAF receptor (PAFR)-mediated cell population expansion, and PAFR expression, were studied by DNA synthesis, western blot analysis and immunocytochemistry. Effects of constructs T19N and G14V on PAF-induced cell proliferation were also investigated. RESULTS Hypoxia increased PVSMC proliferation and Rho kinase inhibitors, Y-27632 and Fasudil (HA-1077) as well as MAPK inhibitors PD 98059 and SB 203580 attenuated PAF stimulation of cell proliferation. RhoA T19N and G14V stimulated cell proliferation, but co-incubation with PAF did not affect proliferative effects of the constructs. PAFR protein expression was significantly downregulated in both cell types by both Y-27632 and HA-1077, with comparable profiles. Also, cells treated with Y-27632 had less PAF receptor fluorescence with significant disruption of cell morphology. CONCLUSIONS Our results show that Rho kinase non-specifically modulated PAFR-mediated responses by a translational modification of PAFR protein, and suggest that, in vivo, activation of Rho kinase by PAF may be a further pathway to sustain PAFR-mediated PVSMC proliferation.
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Affiliation(s)
- L. S. Renteria
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
| | - M. Austin
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
| | - M. Lazaro
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
| | - M. A. Andrews
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
| | - J. Lustina
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
| | - J. U. Raj
- Department of PediatricsUniversity of Illinois ChicagoChicagoIL60612USA
| | - B. O. Ibe
- Division of NeonatologyDepartment of PediatricsLos Angeles Biomedical Research Institute at Harbor‐UCLA Medical CenterTorranceCA90502USA
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20
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The subcellular localization of the receptor for platelet-activating factor in neutrophils affects signaling and activation characteristics. Clin Dev Immunol 2013; 2013:456407. [PMID: 24069041 PMCID: PMC3773398 DOI: 10.1155/2013/456407] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/22/2013] [Indexed: 11/22/2022]
Abstract
The localization in neutrophils, of the receptor for platelet-activating factor (PAFR), has been determined using subcellular fractionation and a receptor mobilization protocol. We show that the PAFR is expressed primarily in the plasma membrane. Although activation of neutrophils by PAF induces responses typical also of agonists that bind the formyl peptide receptors (FPR), known to be stored in mobilizable organelles, some quantitative as well as qualitative differences were observed when neutrophils were activated through these receptors. PAF is equipotent to fMLF (high affinity agonist for FPR1) to cleave off L-selectin and to induce granule/vesicle secretion but is more potent than fMLF to induce a rise in intracellular Ca2+. Similar to fMLF, PAF induced also a robust release of reactive oxygen species, but with higher EC50 value and was less sensitive to a PI3K inhibitor compared to the fMLF response. Despite the lack of a granule localized storage pool of receptors, the PAF-induced superoxide production could be primed; receptor mobilization was, thus, not required for priming of the PAF response. The desensitized PAFR could not be reactivated, suggesting that distinct signaling pathways are utilized for termination of the responses triggered through FPR1 and PAFR.
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22
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Research progress in the mechanism of effect of PRP in bone deficiency healing. ScientificWorldJournal 2013; 2013:134582. [PMID: 23710132 PMCID: PMC3654280 DOI: 10.1155/2013/134582] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 02/27/2013] [Indexed: 12/19/2022] Open
Abstract
Platelet-rich plasma (PRP) therapy is a recently developed technique that uses a concentrated portion of autologous blood to try to improve and accelerate the healing of various tissues. There is a considerable interest in using these PRP products for the treatment used in bone deficiency healing. Because PRP products are safe and easy to prepare and administer, there has been increased attention toward using PRP in numerous clinical settings. The benefits of PRP therapy appear to be promising, and many investigators are exploring the ways in which this therapy can be used in the clinical setting. At present, the molecular mechanisms of bone defect repair studies have focused on three aspects of the inflammatory cytokines, growth factors and angiogenic factors. The role of PRP works mainly through these three aspects of bone repair. The purpose of this paper is to review the current evidence on the mechanism of the effect of PRP in bone deficiency healing.
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23
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Tsoupras AB, Papakyriakou A, Demopoulos CA, Philippopoulos AI. Synthesis, biochemical evaluation and molecular modeling studies of novel rhodium complexes with nanomolar activity against Platelet Activating Factor. J Inorg Biochem 2012; 120:63-73. [PMID: 23318288 DOI: 10.1016/j.jinorgbio.2012.12.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 12/10/2012] [Accepted: 12/10/2012] [Indexed: 12/18/2022]
Abstract
Two square planar Rh(I) organometallic complexes namely [Rh(L(1))(cod)]Cl (cod = cycloocta-1,5-diene, L(1)=2,2'-pyridylquinoxaline (1-Cl), [Rh(L1)(cod)](NO3) (1-NO(3)) and a series of novel octahedral rhodium(III) complexes of the general formulae mer-[Rh(L(1))Cl(3)(MeOH)] (2) and cis-[Rh(L(2))(2)Cl(2)]Cl (L(2)=4 carboxy 2 (2' pyridyl)quinoline (3), L(3)=2,2' bipyridine 4,4' dicarboxylic acid (4) were synthesized and characterized spectroscopically. All the synthesized compounds including the previously prepared cis-[Rh(L(1))(2)Cl(2)]Cl complex (5) were biologically evaluated as potential inhibitors of the Platelet Activation Factor (PAF) and thrombin induced aggregation. In particular compounds 1-Cl and 1-NO(3) were found to be strong inhibitors of PAF with IC(50) values in the range of 16 nM and 15 nM rendering them good candidates for further investigation. Their potency is comparable to that of the widely used PAF receptor antagonists WEB2170, BN52021, and Rupatadine (IC(50) of 20, 30 and 260 nM respectively). Molecular docking calculations suggest that 1-Cl, 1-NO3 and 2 can be accommodated within the ligand-binding site of PAF receptor and block the activity of PAF. On the other hand, the octahedral rhodium(III) complexes 3-5 that cannot fit the ligand-binding domain, could potentially exhibit their activity at the extracellular domain of the receptor.
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Affiliation(s)
- Alexandros B Tsoupras
- Laboratory of Biochemistry, Faculty of Chemistry, National and Kapodistrian University of Athens, Athens 15771, Greece
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Nitoda E, Moschos MM, Mavragani CP, Koutsilieris M. Ocular actions of platelet-activating factor: clinical implications. Expert Opin Ther Targets 2012; 16:1027-39. [DOI: 10.1517/14728222.2012.712961] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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25
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Flasiński M, Broniatowski M, Wydro P, Hąc-Wydro K, Dynarowicz-Łątka P. Behavior of platelet activating factor in membrane-mimicking environment. Langmuir monolayer study complemented with grazing incidence X-ray diffraction and Brewster angle microscopy. J Phys Chem B 2012; 116:10842-55. [PMID: 22834697 DOI: 10.1021/jp302907e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
1-O-octadecyl-2-acetyl-sn-glycero-3-phosphocholine (PAF) belonging to the class of single-chained ether phospholipids is widely known from its essential biological activities. There is a growing body of evidence that some significant aspects of PAF actions are connected with its capability to direct intercalation into biomembranes' environment. Although this mechanism is of great importance in the perspective of understanding PAF implications in various physiological processes, in the literature, there is a lack of studies devoted to this subject. It is still unknown which is the exact influence of membrane composition, molecular organization, and its other properties on the PAF impact on cells and tissues. Unfortunately, the biological studies carried out on cell cultures do not provide satisfactory results, mainly because of the complexity of natural systems. In order to obtain insight into the behavior of PAF in a lipid environment at the molecular level, the application of appropriate model systems is required. Among them, Langmuir monolayers are very often applied as a simple but very efficient platform for studies of the interactions between membrane lipids. In the present paper, special attention is focused on the issue concerning the interactions between PAF and two representatives of membrane components occurring mainly in the outer leaflet of natural bilayers, namely, cholesterol and DPPC. The application of Langmuir monolayers enabled us to construct the effective model mimicking the exogenous incorporation of PAF into membrane environment. On the basis of the obtained results, a thorough discussion was carried out and the conclusions derived from the traditional thermodynamic analysis were confronted with microscopic analysis of surface domains and the GIXD results. The selection of experimental techniques enables us to obtain information regarding the miscibility and interactions in the binary mixed films as well as the molecular organization of film-forming molecules on water surface. The experiments revealed that the addition of the investigated single-chained ether phospholipid into both cholesterol and DPPC monolayers causes a considerable decrease of monolayer condensation. On the basis of thermodynamic analysis, it was found that PAF mixes and consequently interacts strongly with cholesterol, whereas its interactions with DPPC are thermodynamically unfavorable. Differences between the PAF influence on cholesterol and DPPC monolayer found its corroboration in the results obtained with the GIXD technique. Namely, the monolayer of DPPC can incorporate more PAF than the model membrane containing cholesterol. The obtained results indicate that short chained sn-2 ether phospholipid is able to modify model membrane properties in a concentration-dependent way.
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Affiliation(s)
- Michał Flasiński
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland.
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26
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Chini M, Tsoupras AB, Mangafas N, Tsogas N, Papakonstantinou VD, Fragopoulou E, Antonopoulou S, Gargalianos P, Demopoulos CA, Lazanas MC. Effects of HAART on platelet-activating factor metabolism in naive HIV-infected patients I: study of the tenofovir-DF/emtricitabine/efavirenz HAART regimen. AIDS Res Hum Retroviruses 2012; 28:766-75. [PMID: 22050695 DOI: 10.1089/aid.2011.0202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Platelet-activating factor (PAF) is implicated in human immunodeficiency virus (HIV)-related manifestations. Increased PAF synthesis has been recently detected in HIV-infected patients. In this study, we examined in naive HIV-infected patients the in vivo effects of a highly active antiretroviral therapy (HAART) regimen, containing tenofovir-DF/emtricitabine/efavirenz, on PAF metabolism. The specific activities of PAF basic biosynthetic enzymes, PAF-cholinephosphotransferase (PAF-CPT) and lyso-PAF-acetyltransferase (lyso-PAF-AT), but also the ones of PAF-basic catabolic enzymes, PAF acetylhydrolase (PAF-AH) in leukocytes and platelets, and lipoprotein-associated-phospholipase-A(2) (LpPLA(2)) in plasma, were measured in blood samples of eight asymptomatic naive male HIV-infected patients just before and after 1, 3, and 6 months of treatment. CD4 cell counts, viral load, and several biochemical markers were also measured in the same blood samples of these patients. The repeated measures ANOVA and the Pearson r criterion were used to study statistical differences and correlations-partial correlations, while linear mixed models were conducted in order to estimate association(s) between time-dependent changes in these factors. Before treatment, the activities of PAF-CPT in leukocytes and LpPLA(2) in plasma were found to be inversely correlated with CD4 cell counts and positively correlated with the viral load. After 6 months of treatment, the activities of basic PAF-biosynthetic enzymes, PAF-CPT and lyso-PAF-AT, were both reduced in leukocytes. At 6 months, PAF-AH activity was also reduced in these cells, while LpPLA(2) remained stable. The reduction of PAF-CPT occurred even from the first month, while there is a time-dependent correlation between the increase of CD4 and the decrease of both viral load and PAF-CPT of leukocytes during treatment. Apart from its classical antiretroviral activities the tenofovir-DF/emtricitabine/efavirenz regimen also exhibited favorable effects on PAF metabolism and therefore may also display beneficial effects in some HIV-related conditions, such as cardiovascular disease (CVD), in which PAF is implicated.
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Affiliation(s)
- Maria Chini
- 3rd Internal Medicine Department-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | | | - Nikos Mangafas
- 3rd Internal Medicine Department-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Nikos Tsogas
- 3rd Internal Medicine Department-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | | | | | | | - Panagiotis Gargalianos
- 1st Internal Medicine Department-Infectious Diseases Unit, “G. Gennimatas” Hospital, Athens, Greece
| | | | - Marios C. Lazanas
- 3rd Internal Medicine Department-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
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Bruserud Ø. Bidirectional crosstalk between platelets and monocytes initiated by Toll-like receptor: an important step in the early defense against fungal infections? Platelets 2012; 24:85-97. [PMID: 22646762 DOI: 10.3109/09537104.2012.678426] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Monocytes are important in the defense against fungal infections due to their phagocytic and immunoregulatory functions. Platelets also contribute in such immune responses through their release of soluble mediators, including chemokines as well as several other soluble mediators. Both monocytes and platelets express several Toll-like receptors (TLRs) that can recognize fungal molecules and thus initiate intracellular signaling events. TLR ligation on monocytes and platelets may thereby be an early immunological event and function as an initiator of a local proinflammatory crosstalk between platelets and monocytes resulting in (i) monocyte-induced increase of platelet activation and (ii) platelet-associated enhancement of the monocyte activation/function. These effects may have clinical implications both for the efficiency of antifungal treatment and for the predisposition to fungal infections, for example, increased predisposition in patients with thrombocytopenia/monocytopenia due to chemotherapy- or disease-induced bone marrow failure.
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Affiliation(s)
- Øyvind Bruserud
- Department of Heart Disease, Haukeland University Hospital, Bergen, Norway.
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28
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Flasiński M, Broniatowski M, Wydro P, Dynarowicz-Łątka P. Comparative Characteristics of Membrane-Active Single-Chained Ether Phospholipids: PAF and Lyso-PAF in Langmuir Monolayers. J Phys Chem B 2012; 116:3155-63. [DOI: 10.1021/jp2121092] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Michał Flasiński
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Marcin Broniatowski
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
| | - Paweł Wydro
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland
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29
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Doyle TJ, Kaur G, Putrevu SM, Dyson EL, Dyson M, McCunniff WT, Pasham MR, Kim KH, Dufour JM. Immunoprotective properties of primary Sertoli cells in mice: potential functional pathways that confer immune privilege. Biol Reprod 2012; 86:1-14. [PMID: 21900683 DOI: 10.1095/biolreprod.110.089425] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Primary Sertoli cells isolated from mouse testes survive when transplanted across immunological barriers and protect cotransplanted allogeneic and xenogeneic cells from rejection in rodent models. In contrast, the mouse Sertoli cell line (MSC-1) lacks immunoprotective properties associated with primary Sertoli cells. In this study, enriched primary Sertoli cells or MSC-1 cells were transplanted as allografts into the renal subcapsular area of naive BALB/c mice, and their survival in graft sites was compared. While Sertoli cells were detected within the grafts with 100% graft survival throughout the 20-day study, MSC-1 cells were rejected between 11 and 14 days, with 0% graft survival at 20 days posttransplantation. Nonetheless, the mechanism for primary Sertoli cell survival and immunoprotection remains unresolved. To identify immune factors or functional pathways potentially responsible for immune privilege, gene expression profiles of enriched primary Sertoli cells were compared with those of MSC-1 cells. Microarray analysis identified 2369 genes in enriched primary Sertoli cells that were differentially expressed at ±4-fold or higher levels than in MSC-1 cells. Ontological analyses identified multiple immune pathways, which were used to generate a list of 340 immune-related genes. Three functions were identified in primary Sertoli cells as potentially important for establishing immune privilege: suppression of inflammation by specific cytokines and prostanoid molecules, slowing of leukocyte migration by controlled cell junctions and actin polymerization, and inhibition of complement activation and membrane-associated cell lysis. These results increase our understanding of testicular immune privilege and, in the long-term, could lead to improvements in transplantation success.
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Affiliation(s)
- Timothy J Doyle
- Center for Reproductive Biology, School of Molecular Biosciences, Washington State University, Pullman, USA
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30
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Smit JJ, Willemsen K, Hassing I, Fiechter D, Storm G, van Bloois L, Leusen JHW, Pennings M, Zaiss D, Pieters RHH. Contribution of classic and alternative effector pathways in peanut-induced anaphylactic responses. PLoS One 2011; 6:e28917. [PMID: 22194949 PMCID: PMC3237567 DOI: 10.1371/journal.pone.0028917] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 11/17/2011] [Indexed: 12/11/2022] Open
Abstract
Food allergy affects approximately 5% of children and is the leading cause of hospitalization for anaphylactic reactions in westernized countries. However, the pathways of anaphylaxis in food allergy are still relatively unknown. We investigated the effector pathways of allergic and anaphylactic responses of different strains of mice in a clinical relevant model of peanut allergy. C3H/HeOuJ, C57BL/6 and BALB/c mice were sensitized by intragastric peanut extract and challenged by intragastric or intraperitoneal injection of peanut. Peanut-specific T cell responses, IgE, IgG1 and IgG2a and mucosal mast cell degranulation were induced to different extent in C3H/HeOuJ, C57BL/6 and BALB/c mice. Interestingly, anaphylactic symptoms after systemic challenge were highest in C3H/HeOuJ followed by C57BL/6 but were absent in BALB/c mice. Mechanistic studies showed that the food allergic systemic anaphylaxis was dependent on platelets, FcRγ and mast cells, and partially dependent on platelet activating factor and monocytes/macrophages, depending on mouse strain. These data demonstrate that in three mouse strains, components of the classic and alternative anaphylactic cascade are differently expressed, leading to differential outcomes in parameters of allergic disease and food induced systemic anaphylaxis.
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Affiliation(s)
- Joost J Smit
- Immunotoxicology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
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31
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Tsoupras AB, Demopoulos CA, Pappas KM. Platelet‐activating factor detection, metabolism, and inhibitors in the ethanologenic bacterium
Zymomonas mobilis. EUR J LIPID SCI TECH 2011. [DOI: 10.1002/ejlt.201000489] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alexandros B. Tsoupras
- Laboratory of Biochemistry, Faculty of Chemistry, National & Kapodistrian University of Athens, Panepistimioupolis, Zografou, Athens, Greece
- Center of Cardiovascular Sciences, Albany Medical Center/College, Albany, NY, USA
| | - Constantinos A. Demopoulos
- Laboratory of Biochemistry, Faculty of Chemistry, National & Kapodistrian University of Athens, Panepistimioupolis, Zografou, Athens, Greece
| | - Katherine M. Pappas
- Faculty of Biology, Department of Genetics and Biotechnology, National & Kapodistrian University of Athens, Panepistimioupolis, Zografou, Athens, Greece
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Silva IT, Mello APQ, Damasceno NRT. Antioxidant and inflammatory aspects of lipoprotein-associated phospholipase A₂ (Lp-PLA₂): a review. Lipids Health Dis 2011; 10:170. [PMID: 21955667 PMCID: PMC3204246 DOI: 10.1186/1476-511x-10-170] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 09/28/2011] [Indexed: 12/11/2022] Open
Abstract
The association of cardiovascular events with Lp-PLA2 has been studied continuously today. The enzyme has been strongly associated with several cardiovascular risk markers and events. Its discovery was directly related to the hydrolysis of the platelet-activating factor and oxidized phospholipids, which are considered protective functions. However, the hydrolysis of bioactive lipids generates lysophospholipids, compounds that have a pro-inflammatory function. Therefore, the evaluation of the distribution of Lp-PLA2 in the lipid fractions emphasized the dual role of the enzyme in the inflammatory process, since the HDL-Lp-PLA2 enzyme contributes to the reduction of atherosclerosis, while LDL-Lp-PLA2 stimulates this process. Recently, it has been verified that diet components and drugs can influence the enzyme activity and concentration. Thus, the effects of these treatments on Lp-PLA2 may represent a new kind of prevention of cardiovascular disease. Therefore, the association of the enzyme with the traditional assessment of cardiovascular risk may help to predict more accurately these diseases.
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Affiliation(s)
- Isis T Silva
- Departamento de Nutrição, Faculdade de Saúde Pública, Universidade de São Paulo, São Paulo, SP, Brazil
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Tsoupras AB, Chini M, Mangafas N, Tsogas N, Stamatakis G, Tsantila N, Fragopoulou E, Antonopoulou S, Gargalianos P, Demopoulos CA, Lazanas MC. Platelet-Activating Factor and Its Basic Metabolic Enzymes in Blood of Naive HIV-Infected Patients. Angiology 2011; 63:343-52. [DOI: 10.1177/0003319711420608] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
| | - Maria Chini
- 3rd Internal Medicine Department, Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Nikos Mangafas
- 3rd Internal Medicine Department, Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Nikos Tsogas
- 3rd Internal Medicine Department, Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - George Stamatakis
- Department of Chemistry, National and Kapodistrian University of Athens, Greece
| | - Nektaria Tsantila
- Department of Chemistry, National and Kapodistrian University of Athens, Greece
| | - Elizabeth Fragopoulou
- Department of Dietetics and Nutritional Science, Harokopio University, Athens, Greece
| | - Smaragdi Antonopoulou
- Department of Dietetics and Nutritional Science, Harokopio University, Athens, Greece
| | - Panagiotis Gargalianos
- 1st Internal Medicine Department, Infectious Diseases Unit, “G. Gennimatas” Hospital, Athens, Greece
| | | | - Marios C. Lazanas
- 3rd Internal Medicine Department, Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
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Perialveolar bacterial microbiota and bacteraemia after dental alveolitis in adult rats that had been subjected to neonatal malnutrition. Br J Nutr 2011; 107:996-1005. [PMID: 21816120 DOI: 10.1017/s000711451100393x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of the present study was to analyse the bacteriological factors during the process of dental alveolitis, relating it to a higher incidence of bacteraemia in adult rats subjected to neonatal malnutrition. We used forty male Wistar rats, suckled by mothers fed a diet during lactation containing 17 % protein in the nourished group (N) or 8 % protein in the undernourished group (UN). After weaning, the animals were given the Labina standard diet. After 90 d, these animals underwent upper right incisor extraction and induction of alveolitis. The oral microbiota was obtained using a swab and blood culture through venous blood. These procedures were performed before the extraction, 5 min after extraction, on the 21st day after alveolitis for groups N-21 and UN-21 and on the 28th day after alveolitis for groups N-28 and UN-28. Data were expressed as means and standard deviations for parametric data, and as medians and interquartile intervals for non-parametric data. Statistical significance was considered by assuming a critical level of 5 %. Before and after extraction, lower bacterial growth was observed per colony-forming unit (CFU) in the perialveolar region of the upper right incisors of undernourished animals, while the opposite was true after alveolitis, when a larger number of CFU was observed in these animals. The percentage of positive blood cultures obtained after alveolitis was greater in the undernourished animals. The present study thus demonstrated the influence of neonatal malnutrition in the perialveolar microbiota and in the development of bacteraemia after dental alveolitis.
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Tsoupras AB, Chini M, Tsogas N, Lioni A, Tsekes G, Demopoulos CA, Lazanas MC. In vitro anti-inflammatory and anti-coagulant effects of antibiotics towards Platelet Activating Factor and thrombin. J Inflamm (Lond) 2011; 8:17. [PMID: 21736752 PMCID: PMC3162514 DOI: 10.1186/1476-9255-8-17] [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: 08/23/2010] [Accepted: 07/07/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sepsis is characterized as a systemic inflammatory response that results from the inability of the immune system to limit bacterial spread during an ongoing infection. In this condition the significant mediator of inflammation Platelet Activating Factor (PAF) and the coagulant factor thrombin are implicated. In animal models, treatment with PAF-antagonists or co-administration of antibiotics with recombinant-PAF-Acetylhydrolase (rPAF-AH) have exhibited promising results. In order to examine the putative anti-inflammatory and/or antithrombotic interactions between antibiotic treatment used in sepsis with PAF and/or thrombin, we studied the in vitro effects of these compounds towards PAF or/and thrombin related activities and towards PAF basic metabolic enzymes. METHODS We assessed the inhibitory effect of these drugs against PAF or thrombin induced aggregation on washed rabbit platelets (WRPs) or rabbit Platelet Reach Plasma (rPRP) by evaluating their IC50 values. We also studied their effect on Cholinephosphotransferase of PAF (PAF-CPT)/Lyso-PAF-Acetyltransferase (Lyso-PAF-AT) of rabbit leukocytes (RLs), as well as on rabbit plasma-PAF-AH, the key enzymes of both de novo/remodelling PAF biosynthesis and PAF degradation, respectively. RESULTS Several antibiotics inhibited PAF-induced platelet aggregation of both WRPs and rPRP in a concentration-depended manner, with clarithromycin, azithromycin and amikacin exhibiting the higher inhibitory effect, while when combined they synergistically inhibited PAF. Higher concentrations of all antibiotics tested were needed in order to inhibit PAF induced aggregation of rPRP, but also to inhibit thrombin induced aggregation of WRPs. Concentrations of these drugs similar to their IC50 values against PAF activity in WRPs, inhibited also in vitro PAF-CPT and Lyso-PAF-AT activities of rabbit leukocytes, while only clarithromycin and azithromycin increased rabbit plasma-PAF-AH activity. CONCLUSIONS These newly found properties of antibiotics used in sepsis suggest that apart from their general actions, these drugs may present additional beneficial anti-inflammatory and anti-coagulant effects against the onset and establishment of sepsis by inhibiting the PAF/PAF-receptor and/or the thrombin/protease-activated-receptor-1 systems, and/or by reducing PAF-levels through both PAF-biosynthesis inhibition and PAF-catabolism induction. These promising in vitro results need to be further studied and confirmed by in vivo tests, in order to optimize the efficacy of antibiotic treatment in sepsis.
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Affiliation(s)
- Alexandros B Tsoupras
- Faculty of Chemistry, National & Kapodistrian University of Athens, Panepistimioupolis of Zografou, Athens, 15771, Greece
| | - Maria Chini
- 3rd Internal Medicine Dept.-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Nickolaos Tsogas
- 3rd Internal Medicine Dept.-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Athina Lioni
- 3rd Internal Medicine Dept.-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - George Tsekes
- 3rd Internal Medicine Dept.-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
| | - Constantinos A Demopoulos
- Faculty of Chemistry, National & Kapodistrian University of Athens, Panepistimioupolis of Zografou, Athens, 15771, Greece
| | - Marios C Lazanas
- 3rd Internal Medicine Dept.-Infectious Diseases Unit, Red Cross General Hospital, Athens, Greece
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Howard KM, Abdel-Al M, Ditmyer M, Patel N. Lipopolysaccharide and platelet-activating factor stimulate expression of platelet-activating factor acetylhydrolase via distinct signaling pathways. Inflamm Res 2011; 60:735-44. [PMID: 21432021 DOI: 10.1007/s00011-011-0326-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 02/22/2011] [Accepted: 03/03/2011] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES This study was designed to investigate and characterize the ability of platelet-activating factor (PAF) to induce the expression of platelet-activating factor acetylhydrolase (PAF-AH). METHODS Ribonuclease protection assays and quantitative real-time PCR were used to investigate the ability of lipopolysaccharide (LPS) and PAF to regulate PAF-AH mRNA expression in human monocyte-macrophage 6 (MM6) cells. Pharmacological inhibitors of mitogen activated protein kinases (MAPK) and PAF receptor antagonists were used to investigate the mechanism of regulation of PAF-AH. RESULTS PAF-AH mRNA levels were increased upon exposure to LPS or PAF in a dose-dependent manner. LPS elicited a more potent and rapid increase in PAF-AH expression than the PAF-stimulated response. However, when administered concomitantly, PAF augmented the LPS-stimulated response. LPS-stimulated PAF-AH expression was susceptible to partial inhibition by a p38 MAPK inhibitor and PAF receptor antagonists. PAF-induced up-regulation of PAF-AH levels was solely mediated via the PAF receptor and was p38 MAPK-independent. CONCLUSION The proinflammatory mediators, LPS and PAF, increased levels of PAF-AH mRNA via distinct signaling pathways.
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Affiliation(s)
- Katherine M Howard
- Department of Biomedical Sciences, University of Nevada Las Vegas School of Dental Medicine, 1001 Shadow Lane, Las Vegas, Nevada 89106, USA.
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Structurally diverse metal coordination compounds, bearing imidodiphosphinate and diphosphinoamine ligands, as potential inhibitors of the platelet activating factor. Bioinorg Chem Appl 2010. [PMID: 20689709 PMCID: PMC2905917 DOI: 10.1155/2010/731202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 05/03/2010] [Indexed: 11/18/2022] Open
Abstract
Metal complexes bearing dichalcogenated imidodiphosphinate [R2P(E)NP(E)R2′]− ligands (E = O, S, Se, Te), which act as (E,E) chelates, exhibit a remarkable variety of three-dimensional structures. A series of such complexes, namely, square-planar [Cu{(OPPh2)(OPPh2)N-O, O}2], tetrahedral [Zn{(EPPh2)(EPPh2)N-E,E}2], E = O, S, and octahedral [Ga{(OPPh2)(OPPh2)N-O,O}3], were tested as potential inhibitors of either the platelet activating factor (PAF)- or thrombin-induced aggregation in both washed rabbit platelets and rabbit platelet rich plasma. For comparison, square-planar [Ni{(Ph2P)2N-S-CHMePh-P, P}X2], X = Cl, Br, the corresponding metal salts of all complexes and the (OPPh2)(OPPh2)NH ligand were also investigated. Ga(O,O)3 showed the highest anti-PAF activity but did not inhibit the thrombin-related pathway, whereas Zn(S,S)2, with also a significant PAF inhibitory effect, exhibited the highest thrombin-related inhibition. Zn(O,O)2 and Cu(O,O)2 inhibited moderately both PAF and thrombin, being more effective towards PAF. This work shows that the PAF-inhibitory action depends on the structure of the complexes studied, with the bulkier Ga(O,O)3 being the most efficient and selective inhibitor.
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Philippopoulos AI, Tsantila N, Demopoulos CA, Raptopoulou CP, Likodimos V, Falaras P. Synthesis, characterization and crystal structure of the cis-[RhL2Cl2]Cl complex with the bifunctional ligand (L) 2-(2′-pyridyl)quinoxaline. Biological activity towards PAF (Platelet Activating Factor) induced platelet aggregation. Polyhedron 2009. [DOI: 10.1016/j.poly.2009.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Ibe BO, Abdallah MF, Portugal AM, Raj JU. Platelet-activating factor stimulates ovine foetal pulmonary vascular smooth muscle cell proliferation: role of nuclear factor-kappa B and cyclin-dependent kinases. Cell Prolif 2008; 41:208-29. [PMID: 18336468 DOI: 10.1111/j.1365-2184.2008.00517.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVE Platelet-activating factor (PAF) is implicated in pathogenesis of persistent pulmonary hypertension of the neonate (PPHN); PAF is a mitogen for lung fibroblasts. PAF's role in pulmonary vascular smooth muscle cell (PVSMC) proliferation and in hypoxia-induced pulmonary vein (PV) remodelling has not been established and mechanisms for PAF's cell-proliferative effects are not well understood. We investigated involvement of PAF and PAF receptors in PVSMC proliferation. MATERIALS AND METHODS Cells from pulmonary arteries (SMC-PA) and veins (SMC-PV) were serum starved for 72 h in 5% CO2 in air (normoxia). They were cultured for 24 h more in normoxia or 2% O(2) (hypoxia) in 0.1% or 10% foetal bovine serum with 5 microCi/well of [(3)H]-thymidine, with and without 10 nm PAF. Nuclear factor-kappa B (NF-kappaB), CDK2 and CDK4 protein expression, and their roles in cell proliferation control were studied. RESULTS PAF and hypoxia increased SMC-PA and SMC-PV proliferation. WEB2170 inhibited PAF-induced cell proliferation while lyso-PAF had no effect. SMC-PV proliferated more than SMC-PA and PAF plus hypoxia augmented NF-kappaB protein expression. NF-kappaB inhibitory peptide attenuated PAF-induced cell proliferation by 50% and PAF increased CDK2 and CDK4 protein expression. The data show that hypoxia and PAF up-regulate PVSMC proliferation via PAF receptor-specific pathway involving NF-kappaB, CDK2 and CDK4 activations. CONCLUSION They suggest that in vivo, in foetal lung low-oxygen environment, where PAF level is high, proliferation of PVSMC will occur readily to modulate PV development and that failure of down-regulation of PAF effects postnatally may result in PPHN.
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Affiliation(s)
- B O Ibe
- Division of Neonatology, Harbor-UCLA Medical Center, Los Angeles Biomedical Institute, Harbor-UCLA Medical Center, 1124 West Carson Street, Torrance, CA 90502, USA.
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Grypioti AD, Kostopanagiotou G, Demopoulos CA, Roussos A, Mykoniatis M. Platelet activating factor (PAF) antagonism with ginkgolide B protects the liver against acute injury. importance of controlling the receptor of PAF. Dig Dis Sci 2008; 53:1054-62. [PMID: 17934819 DOI: 10.1007/s10620-007-9982-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 08/15/2007] [Indexed: 01/24/2023]
Abstract
Platelet activating factor (PAF) is an ubiquitous phospholipid that acts as a mediator of numerous pathophysiological conditions, including hepatotoxicity. The present study has been conducted to evaluate the eventual role of the platelet activating factor in post-acetaminophen intoxication of liver, using ginkgolide B, BN52021, a selective PAF receptor antagonist. One group of rats was treated with a toxic dose of acetaminophen (APAP) (3.5 g/kg b.w.) (control group) and a second one with the same dose of APAP followed by a dose of ginkgolide B, BN52021 (10 mg/kg b.w.) (BN52021-treated group). The animals were killed at 8, 16, 24, 32 and 40 h after treatment. APAP was found to cause an acute hepatic injury, evident by alterations of biochemical (serum enzymes: ALT, AST and ALP) and liver histopathological (degree of inflammation and apoptosis) indices, which was followed by liver regeneration evident by three independent indices ([3H] thymidine incorporation into hepatic DNA, liver thymidine kinase activity and hepatocyte mitotic index). Hepatic levels of malondialdehyde and serum cholesterol/HDL cholesterol fraction were also measured as parameters of oxidant-antioxidant balance. The protected effects of ginkgolide B were qualified during post treatment time by: (1) reduction of oxidative stress, (2) high decrease of hepatic injury, and (3) decrease of regenerating activity. These results indicate that PAF may play an important role in APAP-induced liver injury and regeneration, and that the use of ginkgolide B attenuates liver damage providing important means of improving liver function following acetaminophen intoxication.
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Affiliation(s)
- Agni D Grypioti
- Department of Experimental Pharmacology, Medical School, National and Kapodistrian University of Athens, 25, Idaspou Street, Ano Ilisia, Athens 157 72, Greece.
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LeBlanc CJ, Horohov DW, Bauer JE, Hosgood G, Mauldin GE. Effects of dietary supplementation with fish oil on in vivo production of inflammatory mediators in clinically normal dogs. Am J Vet Res 2008; 69:486-93. [DOI: 10.2460/ajvr.69.4.486] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
This review considers biochemical aspects of inflammation. The international literature until December 2006 has been analyzed, with the principal attention paid to the most dynamic problems: enzymology of inflammation, its regulation by hormones and signal transducers, and negative feedbacks, which underlie intensive current studies on pathogenesis, diagnostics, and therapy of inflammation. Such achievements as discoveries of defensins, toll-like receptors, interconnections of inflammation and iron metabolism, the roles of oxidative stress and antioxidant defense, lipoxins, inflammatory components of "non-inflammatory" diseases, and action mechanisms of effective drugs are discussed.
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Affiliation(s)
- V I Kulinsky
- Department of Biochemistry, Irkutsk State Medical University, Irkutsk 664003, Russia.
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43
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Schenkein HA, Barbour SE, Tew JG. Cytokines and inflammatory factors regulating immunoglobulin production in aggressive periodontitis. Periodontol 2000 2007; 45:113-27. [PMID: 17850452 DOI: 10.1111/j.1600-0757.2007.00214.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Harvey A Schenkein
- Department of Periodontics, Virginia Commonwealth University, School of Dentistry, Richmond, VA, USA
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Shin CR, Moores J, Best AM, Tew JG, Schenkein HA, Barbour SE. Differential platelet-activating factor synthesis by monocytes and polymorphonuclear leukocytes from subjects with localized aggressive periodontitis. J Periodontal Res 2007; 42:202-11. [PMID: 17451539 DOI: 10.1111/j.1600-0765.2006.00933.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVE Platelet-activating factor is elevated in localized aggressive periodontitis. We previously demonstrated that the elevated level of platelet-activating factor in localized aggressive periodontitis is at least partially attributable to low levels of platelet-activating factor acetylhydrolase, the enzyme that catabolizes platelet-activating factor. The objective of this study was to determine if platelet-activating factor synthesis was also elevated in localized aggressive periodontitis. To test this, platelet-activating factor synthesis was quantified in the monocytes and polymorphonuclear neutrophils of periodontally healthy patients and of subjects with localized aggressive periodontitis. MATERIAL AND METHODS Cells were labeled with [(3)H]acetate and treated with vehicle or stimulated with calcium ionophore A23187. Platelet-activating factor was extracted and quantified by scintillation counting. RESULTS For both subject groups, resting monocytes and polymorphonuclear neutrophils produced platelet-activating factor, and calcium ionophore A23187 stimulated platelet-activating factor production in both cell types. However, calcium ionophore A23187-activated monocytes from subjects with localized aggressive periodontitis produced less platelet-activating factor than did activated periodontally healthy monocytes (p < 0.0001), suggesting an aberrant calcium ionophore A23187 response in monocytes from subjects with localized aggressive periodontitis. Indeed, when the data were expressed as fold induction of platelet-activating factor synthesis in response to calcium ionophore A23187, monocytes from subjects with localized aggressive periodontitis exhibited only a fourfold increase in platelet-activating factor synthesis, whereas calcium ionophore A23187-stimulated monocytes from periodontally healthy, chronic periodontitis and generalized aggressive periodontitis subjects produced approximately 12 times more platelet-activating factor than did resting monocytes. In contrast, both resting and activated localized aggressive periodontitis polymorphonuclear neutrophils synthesized more platelet-activating factor than did periodontally healthy polymorphonuclear neutrophils. CONCLUSION These data suggest that high levels of platelet-activating factor in subjects with localized aggressive periodontitis result from both increased synthesis and reduced catabolism. While localized aggressive periodontitis polymorphonuclear neutrophils contribute to increased platelet-activating factor mass through synthesis, the contribution of monocytes is probably the result of reduced catabolism by platelet-activating factor acetylhydrolase.
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Affiliation(s)
- C R Shin
- Department of Biochemistry, Virginia Commonwealth University, Richmond, VA 23298-0614, USA
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Seo HS, Kim JH, Nahm MH. Platelet-activating factor-acetylhydrolase can monodeacylate and inactivate lipoteichoic acid. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2006; 13:452-8. [PMID: 16603612 PMCID: PMC1459642 DOI: 10.1128/cvi.13.4.452-458.2006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Bacterial lipoteichoic acid (LTA) shares a structural motif with platelet-activating factor (PAF). Both molecules are strong inflammatory agents and have a glycerol backbone with two lipid chains at the sn-1 and sn-2 positions. PAF is normally inactivated by PAF-acetylhydrolase (PAF-AH), a phospholipase A2 (PLA2), which removes a short acyl group at the sn-2 position. To investigate whether PAF-AH can similarly degrade LTA, we studied the effects of porcine PLA2, bee venom PLA2, and recombinant human PAF-AH on pneumococcal LTA (PnLTA) and staphylococcal LTA (StLTA). After incubation with a porcine or bee venom PLA2, a large fraction of PnLTA lost 264 Da, which corresponds to the mass of the oleic acid group at the sn-2 position. After incubation with recombinant human PAF-AH, PnLTA lost 264 Da; the reduction did not occur when PAF-AH was exposed to Pefabloc SC, an irreversible inhibitor of the PAF-AH active site. Following PAF-AH treatment, PnLTA and StLTA were not able to stimulate mouse RAW 264.7 cells to produce tumor necrosis factor alpha but could stimulate CHO cells expressing human TLR2. This stimulation pattern has been observed with monoacyl PnLTA prepared by mild alkali hydrolysis (22). Taking these data together, we conclude that PAF-AH can remove one acyl chain at the sn-2 position of LTA and produce a monoacyl-LTA that is inactive against mouse cells.
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Affiliation(s)
- Ho Seong Seo
- Department of Pathology, University of Alabama at Birmingham, 845 19th St. South (BBRB 614), Birmingham, AL 35249-7331, USA
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Tsoupras AB, Antonopoulou S, Baltas G, Samiotaki M, Panayotou G, Kotsifaki H, Mantzavinos Z, Demopoulos CA. Isolation and identification of hydroxyl-platelet-activating factor from natural sources. Life Sci 2006; 79:1796-803. [PMID: 16860827 DOI: 10.1016/j.lfs.2006.06.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Revised: 05/31/2006] [Accepted: 06/09/2006] [Indexed: 11/17/2022]
Abstract
Platelet-activating factor (PAF), a potent inflammatory mediator that has previously been detected in elevated levels in inflamed gingival tissues, in gingival crevicular fluid (GCF) and in saliva, is implicated in periodontal disease. The biologically active phospholipid detected in gingival crevicular fluid is a hydroxyl-PAF analogue. In a preliminary study this bioactive molecule was detected for the first time in human blood derived from volunteers with chronic periodontitis as well as from periodontally healthy volunteers. Compounds isolated from natural sources as well as synthetic ones have been reported as biologically active lipids with physiological importance based on the fact that they induce platelet aggregation with EC50 values ranging from 100 to 0.01 microM through interaction with G-protein-coupled receptors like the PAF receptor, leading to altered signal transduction. In this study, the existence of hydroxyl-PAF analogue in human blood was further studied as well as its distribution in plasma and in blood components. The existence of hydroxyl-PAF analogue was also investigated in samples from rabbit blood hen's egg yolk. The hydroxyl-PAF analogue was purified by high-performance liquid chromatography, detected by biological assays and identified by electrospray MS analysis. Quantitative determination of PAF and hydroxyl-PAF analogue (expressed as PAF-like activity) showed a statistically significant increase in the ratio of plasma hydroxyl-PAF analogue levels to plasma PAF levels in volunteers with periodontitis. Moreover, hydroxyl-PAF analogue was also detected in rabbit blood and hen's egg yolk samples. These data support that this bioactive lipid may play a role in oral inflammation and suggest PAF as a member of a lipid molecule family with different structures and from different sources which share the same or similar biological activities, apparently with different physiological roles in human and animals.
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Affiliation(s)
- Alexandros B Tsoupras
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimioupolis, Athens, Greece
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Han SH, Kim JH, Seo HS, Martin MH, Chung GH, Michalek SM, Nahm MH. Lipoteichoic acid-induced nitric oxide production depends on the activation of platelet-activating factor receptor and Jak2. THE JOURNAL OF IMMUNOLOGY 2006; 176:573-9. [PMID: 16365452 PMCID: PMC1364485 DOI: 10.4049/jimmunol.176.1.573] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
NO production by macrophages in response to lipoteichoic acid (LTA) and a synthetic lipopeptide (Pam3CSK4) was investigated. LTA and Pam3CSK4 induced the production of both TNF-alpha and NO. Inhibitors of platelet-activating factor receptor (PAFR) blocked LTA- or Pam3CSK4-induced production of NO but not TNF-alpha. Jak2 tyrosine kinase inhibition blocked LTA-induced production of NO but not TNF-alpha. PAFR inhibition blocked phosphorylation of Jak2 and STAT1, a key factor for expressing inducible NO synthase. In addition, LTA did not induce IFN-beta expression, and p38 mitogen-activated protein serine kinase was necessary for LTA-induced NO production but not for TNF-alpha production. These findings suggest that Gram-positive bacteria induce NO production using a PAFR signaling pathway to activate STAT1 via Jak2. This PAFR/Jak2/STAT1 signaling pathway resembles the IFN-beta, type I IFNR/Jak/STAT1 pathway described for LPS. Consequently, Gram-positive and Gram-negative bacteria appear to have different but analogous mechanisms for NO production.
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Affiliation(s)
- Seung Hyun Han
- Department of Pathology, University of Alabama at Birmingham, AL 35294, USA
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Grypioti AD, Theocharis SE, Demopoulos CA, Papadopoulou-Daifoti Z, Basayiannis AC, Mykoniatis MG. Effect of platelet-activating factor (PAF) receptor antagonist (BN52021) on acetaminophen-induced acute liver injury and regeneration in rats. Liver Int 2006; 26:97-105. [PMID: 16420515 DOI: 10.1111/j.1478-3231.2005.01186.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Platelet-activating factor (PAF) is an endogenous lipid mediator that plays a key role in catalyzing various pro-inflammatory processes associated with acute liver injury. In the present study, the possible influence of PAF-R antagonist (BN52021) on the protection of liver injury after 4-hydroxyacetanilide, N-acetyl-p-aminophenol, paracetamol (APAP) intoxication was investigated. METHODS Thereby, one group of rats was treated with a toxic dose of APAP (3.5 g/kg body weight (b.w.). The animals were killed at 56, 66, 72, 84 and 96 h after treatment. RESULTS APAP was found to cause an acute hepatic injury, evident by alterations of biochemical (serum enzymes: aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase) and liver histopathological (degree of necrosis and apoptosis) indices, which was followed by liver regeneration, evident by three independent indices ([3H] thymidine incorporation into hepatic DNA, liver thymidine kinase activity and hepatocyte mitotic index). The protective effects of BN52021 were qualified during post-treatment time by: (1) significant reduction of hepatic injury as showed by all biochemical and histological parameters, (2) high decrease of regenerating activity showed by three regenerative markers and (3) remarkable increase of PAF-acetylhydrolase (PAF-AH) activity. CONCLUSION These results suggest that PAF may play an important role in APAP-induced liver injury and regeneration, and PAF-R antagonist (BN52021) attenuates liver damage.
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Affiliation(s)
- A D Grypioti
- Department of Experimental Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
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Hudry-Clergeon H, Stengel D, Ninio E, Vilgrain I. Platelet-activating factor increases VE-cadherin tyrosine phosphorylation in mouse endothelial cells and its association with the PtdIns3'-kinase. FASEB J 2005; 19:512-20. [PMID: 15791001 PMCID: PMC4848345 DOI: 10.1096/fj.04-2202com] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Platelet-activating factor (PAF), a potent inflammatory mediator, is involved in endothelial permeability. This study was designed to characterize PAF receptor (PAF-R) expression and its specific contribution to the modifications of adherens junctions in mouse endothelial cells. We demonstrated that PAF-R was expressed in mouse endothelial cells and was functionally active in stimulating p42/p44 MAPK and phosphatidylinositol 3-kinase (PtdIns3'-kinase)/Akt activities. Treatment of cells with PAF induced a rapid time- and dose-dependent (10(-7) to 10(-10) M) increase in tyrosine phosphorylation of a subset of proteins ranging from 90 to 220 kDa, including the VE-cadherin, the latter effect being prevented by the tyrosine kinase inhibitors herbimycin A and bis-tyrphostin. We demonstrated that PAF promoted formation of multimeric aggregates of VE-cadherin with PtdIns3'-kinase, which was also inhibited by herbimycin and bis-tyrphostin. Finally, we show by immunostaining of endothelial cells VE-cadherin that PAF dissociated adherens junctions. The present data provide the first evidence that treatment of endothelial cells with PAF promoted activation of tyrosine kinases and the VE-cadherin tyrosine phosphorylation and PtdIns3'-kinase association, which ultimately lead to the dissociation of adherens junctions. Physical association between PtdIns3'-kinase, serving as a docking protein, and VE-cadherin may thus provide an efficient mechanism for amplification and perpetuation of PAF-induced cellular activation.
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Affiliation(s)
- Hélène Hudry-Clergeon
- Laboratoire de développement et vieillissement de l'endothélium
Université Joseph FourierINSERMCEA
| | - Dominique Stengel
- Génétique épidémiologique et moléculaire des pathologies cardiovasculaires
Université Pierre et Marie Curie - Paris 6INSERMIFR14Faculté de Médecine Pitié-Salpétrière 91, Boulevard de L'hôpital 75634 Paris cedex 13
| | - Ewa Ninio
- Génétique épidémiologique et moléculaire des pathologies cardiovasculaires
Université Pierre et Marie Curie - Paris 6INSERMIFR14Faculté de Médecine Pitié-Salpétrière 91, Boulevard de L'hôpital 75634 Paris cedex 13
| | - Isabelle Vilgrain
- Laboratoire de développement et vieillissement de l'endothélium
Université Joseph FourierINSERMCEA
- * Correspondence should be addressed to Isabelle Vilgrain
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Vardar S, Buduneli E, Baylas H, Berdeli AH, Buduneli N, Atilla G. Individual and combined effects of selective cyclooxygenase-2 inhibitor and omega-3 fatty acid on endotoxin-induced periodontitis in rats. J Periodontol 2005; 76:99-106. [PMID: 15830643 DOI: 10.1902/jop.2005.76.1.99] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND The present study was planned to evaluate the individual and combined effects of selective cyclooxygenase-2 (COX-2) inhibitor, celecoxib, and omega-3 fatty acid on the gingival tissue levels of prostaglandin E2 (PGE2), prostaglandin F2alpha (PGF2alpha), leukotriene B4 (LTB4), and platelet activating factor (PAF) in endotoxin-induced periodontitis in rats. METHODS Experimental periodontitis was induced by repeated injection of Escherichia coli endotoxin (LPS). Forty-four adult male Sprague-Dawley rats were divided into five study groups: saline control, LPS, celecoxib, omega-3 fatty acid, and combination celecoxib and omega-3 fatty acid. Celecoxib and omega-3 fatty acid were given either as a single agent or as a combination therapy during 14 days of the study period. At the end of the 2-week protocol, the rats were sacrificed, the gingival tissues were dissected and extracted, and the extracts were analyzed for PGE2, PGF2alpha, and LTB4 levels by enzyme immunoassay and for PAF levels by radioimmunoassay. The defleshed jaws were analyzed morphometrically for alveolar bone loss. Data were evaluated statistically by using parametric tests. RESULTS LPS injection resulted in significantly more bone loss than the saline controls (P<0.05) and significant elevations in the gingival tissue levels of all the analyzed mediators except PGF2alpha. Individual administration of celecoxib revealed significant reductions in PGE2 and PAF levels (P <0.05), while omega-3 fatty acid provided significant reduction in PGE2, PGF2alpha, and LTB4 levels compared to the LPS group (P <0.05). Combined administration of celecoxib and omega-3 fatty acid exhibited significantly lower values than those of the LPS group in all the analyzed membrane phospholipid mediators (P <0.05), which approximated the levels in the saline control group (P>0.05). CONCLUSIONS The results of the present study indicate that celecoxib and omega-3 fatty acid, when used individually, show a rather partial effect on the control of the analyzed mediators, but when combined they show a synergic effect and provide significant reductions in the gingival tissue levels of PGE2, PGF2alpha, LTB4, and PAF in LPS-induced experimental periodontitis. These findings may pioneer further clinical human studies investigating the possible place of celecoxib and omega-3 fatty acid in periodontal treatment.
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Affiliation(s)
- Saynur Vardar
- School of Dentistry, Department of Periodontology, Ege University, Izmir, Turkey.
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