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Tate AR, Rao GHR. Inflammation: Is It a Healer, Confounder, or a Promoter of Cardiometabolic Risks? Biomolecules 2024; 14:948. [PMID: 39199336 PMCID: PMC11352362 DOI: 10.3390/biom14080948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2024] [Revised: 07/30/2024] [Accepted: 07/31/2024] [Indexed: 09/01/2024] Open
Abstract
Inflammation is the body's non-specific response to injury or infection. It is a natural defense mechanism that helps to maintain homeostasis and promotes tissue repair. However, excessive inflammation can lead to cellular, tissue, or organ dysfunction, as well as contribute to the development of acute vascular events and diseases like Crohn's disease, psoriasis, obesity, diabetes, and cancer. The initial response to injury involves the activation of platelets and coagulation mechanisms to stop bleeding. This is followed by the recruitment of immune cells and the release of cytokines to promote tissue repair. Over time, the injured tissue undergoes remodeling and returns to its pre-injury state. Inflammation is characterized by the activation of inflammatory signaling pathways involving cytokines, chemokines, and growth factors. Mast cells play a role in initiating inflammatory responses. Pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) and nucleotide-binding domain (NOD)-like receptors (NLRs) are involved in the activation of these inflammatory pathways. Inflammasomes, which are cytoplasmic complexes, also contribute to inflammation by activating cytokines. Inflammation can also be triggered by factors like dietary components and the composition of the gut microbiota. Dysregulation of the gut microbiome can lead to excessive inflammation and contribute to diseases like atherosclerosis and irritable bowel syndrome (IBS). The immune system and gut-associated lymphoid tissue (GALT) play crucial roles in the inflammatory response and the development of conditions like colorectal cancer. Anti-inflammatory therapy can play a significant role in reducing or inducing the remission of inflammatory diseases such as Crohn's disease and ulcerative colitis. The fetal origin of adult diseases theory suggests that conditions during fetal development, such as low birth weight and maternal obesity, can influence the risk of cardiometabolic diseases later in life. All of the known risk factors associated with cardiometabolic diseases such as hypertension, excess weight, obesity, type-2 diabetes, and vascular diseases are accompanied by chronic low-grade inflammation. Inflammation seems to have a role in precipitating even acute vascular events such as heart attacks and stroke. Common markers of inflammation associated with cardiometabolic disease include interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF-α), C-reactive protein (CRP), and soluble TNF receptors such as sTNFR1 and sTNFR2. These markers serve as indicators of systemic inflammation. However, these markers are not disease-specific but provide an insight into the overall chronic inflammatory status. In fact, inflammation has been identified as a potential target for future treatments to reduce or reverse the risk of atherosclerosis-related complications. The regulation of inflammation is complex, and further research is needed to better understand its mechanisms and develop strategies for managing inflammatory disorders. In summary, inflammation is a natural response to injury or infection, but excessive or prolonged inflammation can lead to the progression of various diseases. Understanding the underlying mechanisms of inflammation is important for developing treatments and preventive measures for inflammatory disorders.
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Affiliation(s)
- Amit R. Tate
- South Asian Society on Atherosclerosis and Thrombosis (SASAT), Minneapolis, MN 55455, USA;
| | - Gundu H. R. Rao
- Laboratory Medicine, and Pathology, Thrombosis Research, Lillehei Heart Institute, University of Minnesota, Minneapolis, MN 55455, USA
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Kawanishi H, Koremoto M, Franssen CFM, van Londen M. Clotting Propensity of Surface-Treated Membranes in a Hemodialysis Set-up That Avoids Systemic Anticoagulation. Semin Nephrol 2023; 43:151482. [PMID: 38262850 DOI: 10.1016/j.semnephrol.2023.151482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
The development of biocompatible membranes, aiming to limit the inflammatory response, oxidative stress, and coagulability during hemodialysis, has been an important step in reducing dialysis-related adverse outcomes. This includes a reduction in the risk of clotting of the extracorporeal circuit, thus enabling hemodialysis with a reduced dose or even without systemic anticoagulant drugs in patients with an increased bleeding risk. In this article, we summarize the in vitro research and clinical evidence on the antithrombotic properties of vitamin E- and heparin-coated membranes.
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Affiliation(s)
| | | | - Casper F M Franssen
- Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
| | - Marco van Londen
- Department of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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Mitsui T, Makino S, Tamiya G, Sato H, Kawakami Y, Takahashi Y, Meguro T, Izumino H, Sudo Y, Norota I, Ishii K, Hayasaka K. ALOX12 mutation in a family with dominantly inherited bleeding diathesis. J Hum Genet 2021; 66:753-759. [PMID: 33564083 DOI: 10.1038/s10038-020-00887-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 10/31/2020] [Accepted: 11/25/2020] [Indexed: 12/30/2022]
Abstract
The arachidonic acid (AA) cascade plays a significant role in platelet aggregation. AA released from membrane phospholipids is metabolized by cyclooxygenase (COX) pathway to thromboxane A2 (TXA2) or by 12S-lipoxygenase (ALOX12) to 12-hydroperoxyeicosatetraenoic acid (12-HPETE). In contrast to a well-known role of the COX pathway in platelet aggregation, the role of ALOX12 is not well understood. Platelets of ALOX12-deficient mice exhibit increased sensitivity for ADP-induced aggregation. However, recent evidence strongly suggests a significant role of ALOX12 in platelet aggregation and calcium signaling. 12-HPETE potentiates thrombin- and thromboxane-induced platelet aggregation, and calcium signaling. Inhibition experiments of ALOX12 demonstrated decreased platelet aggregation and calcium signaling in stimulated platelets. We studied a family with a dominantly inherited bleeding diathesis using next-generation sequencing analysis. Platelet aggregation studies revealed that the proband's platelets had defective aggregation responses to ADP, TXA2 mimetic U46619, collagen, and AA, normal affinity of TXA2 receptor for U46619, and normal induction of GTPase activity upon stimulation with U46619. However, the production of inositol 1,4,5-triphosphate (IP3) was only increased up to 30% of the control upon U46619 stimulation, suggesting a defect in phospholipase C-β2 (PLCB2) activation downstream from TXA2 receptors. Affected family members had no mutation of PLCB2, but had a heterozygous c.1946A > G (p.Tyr649Cys) mutation of ALOX12. ALOX12 activity in platelets from the affected members was decreased to 25-35% of the control. Our data strongly suggested that a heterozygous c.1946A > G ALOX12 mutation was a disease-causing mutation; however, further experiments are required to confirm the pathogenesis of ALOX12 mutation in platelet aggregation.
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Affiliation(s)
- Tetsuo Mitsui
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan.
| | - Satoshi Makino
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Gen Tamiya
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan. .,Statistical Genetics Team, RIKEN Center for Advanced Intelligence Project, Tokyo, Japan.
| | - Hiroko Sato
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan
| | - Yuki Kawakami
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Okayama, Japan
| | - Yoshitaka Takahashi
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Okayama, Japan
| | - Toru Meguro
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan
| | - Hiroko Izumino
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan
| | - Yosuke Sudo
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan
| | - Ikuo Norota
- Department of Pharmacology, Yamagata University School of Medicine, Yamagata, Japan
| | - Kuniaki Ishii
- Department of Pharmacology, Yamagata University School of Medicine, Yamagata, Japan
| | - Kiyoshi Hayasaka
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan. .,Department of Pediatrics, Miyukikai Hospital, Social Medical Corporation Miyuki, Kaminoyama, Japan.
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Multifunctional Phytocompounds in Cotoneaster Fruits: Phytochemical Profiling, Cellular Safety, Anti-Inflammatory and Antioxidant Effects in Chemical and Human Plasma Models In Vitro. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:3482521. [PMID: 30510617 PMCID: PMC6230391 DOI: 10.1155/2018/3482521] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 08/30/2018] [Indexed: 12/20/2022]
Abstract
The work presents the results of an investigation into the molecular background of the activity of Cotoneaster fruits, providing a detailed description of their phytochemical composition and some of the mechanisms of their anti-inflammatory and antioxidant effects. GS-FID-MS and UHPLC-PDA-ESI-MS3 methods were applied to identify the potentially health-beneficial constituents of lipophilic and hydrophilic fractions, leading to the identification of fourteen unsaturated fatty acids (with dominant linoleic acid, 375.4–1690.2 mg/100 g dw), three phytosterols (with dominant β-sitosterol, 132.2–463.3 mg/100 g), two triterpenoid acids (10.9–54.5 mg/100 g), and twenty-six polyphenols (26.0–43.5 mg GAE/g dw). The most promising polyphenolic fractions exhibited dose-dependent anti-inflammatory activity in in vitro tests of lipoxygenase (IC50 in the range of 7.7–24.9 μg/U) and hyaluronidase (IC50 in the range of 16.4–29.3 μg/U) inhibition. They were also demonstrated to be a source of effective antioxidants, both in in vitro chemical tests (DPPH, FRAP, and TBARS) and in a biological model, in which at in vivo-relevant levels (1–5 μg/mL) they normalized/enhanced the nonenzymatic antioxidant capacity of human plasma and efficiently protected protein and lipid components of plasma against peroxynitrite-induced oxidative/nitrative damage. Moreover, the investigated extracts did not exhibit cytotoxicity towards human PMBCs. Among the nine Cotoneaster species tested, C. hjelmqvistii, C. zabelii, C. splendens, and C. bullatus possess the highest bioactive potential and might be recommended as dietary and functional food products.
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Yeung J, Li W, Holinstat M. Platelet Signaling and Disease: Targeted Therapy for Thrombosis and Other Related Diseases. Pharmacol Rev 2018; 70:526-548. [PMID: 29925522 PMCID: PMC6013590 DOI: 10.1124/pr.117.014530] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Platelets are essential for clotting in the blood and maintenance of normal hemostasis. Under pathologic conditions such as atherosclerosis, vascular injury often results in hyperactive platelet activation, resulting in occlusive thrombus formation, myocardial infarction, and stroke. Recent work in the field has elucidated a number of platelet functions unique from that of maintaining hemostasis, including regulation of tumor growth and metastasis, inflammation, infection, and immune response. Traditional therapeutic targets for inhibiting platelet activation have primarily been limited to cyclooxygenase-1, integrin αIIbβ3, and the P2Y12 receptor. Recently identified signaling pathways regulating platelet function have made it possible to develop novel approaches for pharmacological intervention in the blood to limit platelet reactivity. In this review, we cover the newly discovered roles for platelets as well as their role in hemostasis and thrombosis. These new roles for platelets lend importance to the development of new therapies targeted to the platelet. Additionally, we highlight the promising receptor and enzymatic targets that may further decrease platelet activation and help to address the myriad of pathologic conditions now known to involve platelets without significant effects on hemostasis.
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Affiliation(s)
- Jennifer Yeung
- Departments of Pharmacology (J.Y., W.L., M.H.) and Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor, Michigan
| | - Wenjie Li
- Departments of Pharmacology (J.Y., W.L., M.H.) and Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor, Michigan
| | - Michael Holinstat
- Departments of Pharmacology (J.Y., W.L., M.H.) and Internal Medicine, Division of Cardiovascular Medicine (M.H.), University of Michigan, Ann Arbor, Michigan
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Lagarde M, Guichardant M, Bernoud-Hubac N, Calzada C, Véricel E. Oxygenation of polyunsaturated fatty acids and oxidative stress within blood platelets. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:651-656. [PMID: 29555597 DOI: 10.1016/j.bbalip.2018.03.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 02/19/2018] [Accepted: 03/14/2018] [Indexed: 12/15/2022]
Abstract
The oxygenation metabolism of arachidonic acid (ArA) has been early described in blood platelets, in particular with its conversion into the potent labile thromboxane A2 that induces platelet aggregation and vascular smooth muscle cells contraction. In addition, the primary prostaglandins D2 and E2 have been mainly reported as inhibitors of platelet function. The platelet 12-lipoxygenase (12-LOX) product, i.e. the hydroperoxide 12-HpETE, appears to stimulate platelet ArA metabolism at the level of its release from membrane phospholipids through phospholipase A2 (cPLA2) and cyclooxygenase (COX-1) activities, the first enzymes in prostanoid production cascade. Also, 12-HpETE may regulate the oxygenation of other polyunsaturated fatty acids (PUFA) by platelets, especially that of eicosapentaenoic acid (EPA). On the other hand, the reduced product of 12-HpETE, 12-HETE, is able to antagonize TxA2 action. This is even more obvious for the 12-LOX end-products from docosahexaenoic acid (DHA), 11- and 14-HDoHE. In addition, 12-HpETE plays a key role in platelet oxidative stress as observed in pathophysiological conditions, but may be regulated by DHA with a bimodal way according to its concentration. Other oxygenated products of PUFA, especially omega-3 PUFA, produced outside platelets may affect platelet functions as well.
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Affiliation(s)
- Michel Lagarde
- Univ Lyon, INSA-Lyon, UMR 1060 Inserm, UMR 1397 Inra, CarMeN Lab, IMBL, F-69621 Villeurbanne, France.
| | - Michel Guichardant
- Univ Lyon, INSA-Lyon, UMR 1060 Inserm, UMR 1397 Inra, CarMeN Lab, IMBL, F-69621 Villeurbanne, France
| | - Nathalie Bernoud-Hubac
- Univ Lyon, INSA-Lyon, UMR 1060 Inserm, UMR 1397 Inra, CarMeN Lab, IMBL, F-69621 Villeurbanne, France
| | - Catherine Calzada
- Univ Lyon, INSA-Lyon, UMR 1060 Inserm, UMR 1397 Inra, CarMeN Lab, IMBL, F-69621 Villeurbanne, France
| | - Evelyne Véricel
- Univ Lyon, INSA-Lyon, UMR 1060 Inserm, UMR 1397 Inra, CarMeN Lab, IMBL, F-69621 Villeurbanne, France
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The expansive role of oxylipins on platelet biology. J Mol Med (Berl) 2017; 95:575-588. [PMID: 28528513 DOI: 10.1007/s00109-017-1542-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 04/29/2017] [Accepted: 05/04/2017] [Indexed: 02/07/2023]
Abstract
In mammals, three major oxygenases, cyclooxygenases (COXs), lipoxygenases (LOXs), and cytochrome P450 (CYP450), generate an assortment of unique lipid mediators (oxylipins) from polyunsaturated fatty acids (PUFAs) which exhibit pro- or anti-thrombotic activity. Over the years, novel oxylipins generated from the interplay of theoxygenase activity in various cells, such as the specialized pro-resolving mediators (SPMs), have been identified and investigated in inflammatory disease models. Although platelets have been implicated in inflammation, the role and mechanism of these SPMs produced from immune cells on platelet function are still unclear. This review highlights the burgeoning classes of oxylipins that have been found to regulate platelet function; however, their mechanism of action still remains to be elucidated.
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Santilli F, Lapenna D, La Barba S, Davì G. Oxidative stress-related mechanisms affecting response to aspirin in diabetes mellitus. Free Radic Biol Med 2015; 80:101-10. [PMID: 25530150 DOI: 10.1016/j.freeradbiomed.2014.12.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 01/19/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is a major cardiovascular risk factor. Persistent platelet activation plays a key role in atherothrombosis in T2DM. However, current antiplatelet treatments appear less effective in T2DM patients vs nondiabetics at similar risk. A large body of evidence supports the contention that oxidative stress, which characterizes DM, may be responsible, at least in part, for less-than-expected response to aspirin, with multiple mechanisms acting at several levels. This review discusses the pathophysiological mechanisms related to oxidative stress and contributing to suboptimal aspirin action or responsiveness. These include: (1) mechanisms counteracting the antiplatelet effect of aspirin, such as reduced platelet sensitivity to the antiaggregating effects of NO, due to high-glucose-mediated oxidative stress; (2) mechanisms interfering with COX acetylation especially at the platelet level, e.g., lipid hydroperoxide-dependent impaired acetylating effects of aspirin; (3) mechanisms favoring platelet priming (lipid hydroperoxides) or activation (F2-isoprostanes, acting as partial agonists of thromboxane receptor), or aldose-reductase pathway-mediated oxidative stress, leading to enhanced platelet thromboxane A2 generation or thromboxane receptor activation; (4) mechanisms favoring platelet recruitment, such as aspirin-induced platelet isoprostane formation; (5) modulation of megakaryocyte generation and thrombopoiesis by oxidative HO-1 inhibition; and (6) aspirin-iron interactions, eventually resulting in impaired pharmacological activity of aspirin, lipoperoxide burden, and enhanced generation of hydroxyl radicals capable of promoting protein kinase C activation and platelet aggregation. Acknowledgment of oxidative stress as a major contributor, not only of vascular complications, but also of suboptimal response to antiplatelet agents in T2DM, may open the way to designing and testing novel antithrombotic strategies, specifically targeting oxidative stress-mediated mechanisms of less-than-expected response to aspirin.
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Affiliation(s)
- Francesca Santilli
- Center of Excellence on Aging, "G. d'Annunzio" University Foundation, and Department of Medicine and Aging, University of Chieti "G. d'Annunzio" School of Medicine, 66013 Chieti, Italy.
| | - Domenico Lapenna
- Center of Excellence on Aging, "G. d'Annunzio" University Foundation, and Department of Medicine and Aging, University of Chieti "G. d'Annunzio" School of Medicine, 66013 Chieti, Italy
| | - Sara La Barba
- Center of Excellence on Aging, "G. d'Annunzio" University Foundation, and Department of Medicine and Aging, University of Chieti "G. d'Annunzio" School of Medicine, 66013 Chieti, Italy
| | - Giovanni Davì
- Center of Excellence on Aging, "G. d'Annunzio" University Foundation, and Department of Medicine and Aging, University of Chieti "G. d'Annunzio" School of Medicine, 66013 Chieti, Italy
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Maskrey BH, Rushworth GF, Law MH, Treweeke AT, Wei J, Leslie SJ, Megson IL, Whitfield PD. 12-hydroxyeicosatetraenoic acid is associated with variability in aspirin-induced platelet inhibition. JOURNAL OF INFLAMMATION-LONDON 2014; 11:33. [PMID: 25349537 PMCID: PMC4209229 DOI: 10.1186/s12950-014-0033-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/08/2014] [Indexed: 02/02/2023]
Abstract
Background Aspirin is one of the most widely used non-steroidal anti-inflammatory drugs (NSAIDs). It is also a commonly used anti-platelet drug, which inhibits the formation of the platelet activator, thromboxane A2 (TxA2) via inhibition of cyclooxygenase-1 (COX-1). However, the presence of a patient subset that fails to respond to aspirin despite reduced TxA2 concentrations suggests that the effect of aspirin might be more complex than exclusive COX-1 inhibition. Methods In this study we evaluated the impact of in vivo oral administration of a standard anti-platelet dose (75 mg) of aspirin in healthy volunteers on the acute impact of in vitro collagen-mediated platelet aggregation and generation of platelet-derived TxA2 and the 12-lipoxygenase (LOX) metabolite 12-hydroxyeicosatetraenoic acid (12-HETE). The eicosanoids were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results Low-dose aspirin administration not only inhibited TxA2 generation but also decreased the production of 12-HETE. Furthermore, a significant correlation was observed between the levels of 12-HETE and collagen-induced platelet aggregation. Pre-treatment of platelets with the 12-LOX inhibitor, baicalein, prior to activation attenuated platelet aggregation. Conclusions These findings support a role for 12-HETE as a pro-aggregatory eicosanoid in platelet function and suggest a role for 12-HETE in variable sensitivity to aspirin. The study also highlights a potentially important mechanism by which aspirin impacts upon eicosanoid generation.
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Affiliation(s)
- Benjamin H Maskrey
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
| | | | - Matthew H Law
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
| | - Andrew T Treweeke
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
| | - Jun Wei
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
| | | | - Ian L Megson
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
| | - Phillip D Whitfield
- Department of Diabetes and Cardiovascular Science, University of the Highlands and Islands, Old Perth Road, Inverness, IV2 3JH UK
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Porro B, Songia P, Squellerio I, Tremoli E, Cavalca V. Analysis, physiological and clinical significance of 12-HETE: a neglected platelet-derived 12-lipoxygenase product. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 964:26-40. [PMID: 24685839 DOI: 10.1016/j.jchromb.2014.03.015] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 03/07/2014] [Accepted: 03/09/2014] [Indexed: 11/25/2022]
Abstract
While the importance of cyclooxygenase (COX) in platelet function has been amply elucidated, the identification of the role of 12-lipoxygenase (12-LOX) and of its stable metabolite, 12-hydroxyeicosatretraenoic acid (12-HETE), has not been clarified as yet. Many studies have analysed the implications of 12-LOX products in different pathological disorders but the information obtained from these works is controversial. Several analytical methods have been developed over the years to simultaneously detect eicosanoids, and specifically 12-HETE, in different biological matrices, essentially enzyme-linked immunosorbent assays (ELISA), radioimmunoassays (RIA), high performance liquid chromatography (HPLC) and mass spectrometry coupled with both gas and liquid chromatography methods (GC- and LC-MS). This review is aimed at summarizing the up to now known physiological and clinical features of 12-HETE together with the analytical methods used for its determination, focusing on the critical issues regarding its measurement.
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Affiliation(s)
| | | | | | - Elena Tremoli
- Centro Cardiologico Monzino-IRCCS, Milan, Italy; Università degli Studi di Milano, Dipartimento di Scienze Farmacologiche e Biomolecolari, Milan, Italy
| | - Viviana Cavalca
- Centro Cardiologico Monzino-IRCCS, Milan, Italy; Dipartimento di Scienze Cliniche e di Comunità, Milan, Italy.
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Lagarde M, Bernoud-Hubac N, Calzada C, Véricel E, Guichardant M. Lipidomics of essential fatty acids and oxygenated metabolites. Mol Nutr Food Res 2013; 57:1347-58. [PMID: 23818385 DOI: 10.1002/mnfr.201200828] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 05/02/2013] [Accepted: 05/02/2013] [Indexed: 01/12/2023]
Abstract
Polyunsaturated fatty acids in mammals may be oxygenated into a myriad of bioactive products through di- and monooxygenases, products that are rapidly degraded to control their action. To evaluate the phenotypes of biological systems regarding this wide family of compounds, a lipidomics approach in function of time and compartments would be relevant. The current review takes into consideration most of the diverse oxygenated metabolites of essential fatty acids at large and their immediate degradation products. Their biological function and life span are considered. Overall, this is a fluxolipidomics approach that is emerging.
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Affiliation(s)
- Michel Lagarde
- Université de Lyon, UMR 1060 Inserm, IMBL, INSA-Lyon, Villeurbanne, France.
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Burzaco J, Conde M, Parada LA, Zugaza JL, Dehaye JP, Marino A. ATP antagonizes thrombin-induced signal transduction through 12(S)-HETE and cAMP. PLoS One 2013; 8:e67117. [PMID: 23826207 PMCID: PMC3691129 DOI: 10.1371/journal.pone.0067117] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/15/2013] [Indexed: 11/18/2022] Open
Abstract
In this study we have investigated the role of extracellular ATP on thrombin induced-platelet aggregation (TIPA) in washed human platelets. ATP inhibited TIPA in a dose-dependent manner and this inhibition was abolished by apyrase but not by adenosine deaminase (ADA) and it was reversed by extracellular magnesium. Antagonists of P2Y1 and P2Y12 receptors had no effect on this inhibition suggesting that a P2X receptor controlled ATP-mediated TIPA inhibition. ATP also blocked inositol phosphates (IP1, IP2, IP3) generation and [Ca(2+)]i mobilization induced by thrombin. Thrombin reduced cAMP levels which were restored in the presence of ATP. SQ-22536, an adenylate cyclase (AC) inhibitor, partially reduced the inhibition exerted by ATP on TIPA. 12-lipoxygenase (12-LO) inhibitors, nordihidroguaretic acid (NDGA) and 15(S)-hydroxy-5,8,11,13-eicosatetraenoic acid (15(S)-HETE), strongly prevented ATP-mediated TIPA inhibition. Additionally, ATP inhibited the increase of 12(S)-hydroxy-5,8,10,14-eicosatetraenoic acid (12(S)-HETE) induced by thrombin. Pretreatment with both SQ-22536 and NDGA almost completely abolished ATP-mediated TIPA inhibition. Our results describe for the first time that ATP implicates both AC and 12-LO pathways in the inhibition of human platelets aggregation in response to agonists.
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Affiliation(s)
- Jaione Burzaco
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Bilbao, Spain
| | - Manuel Conde
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Bilbao, Spain
| | - Luis A. Parada
- Instituto de Patología Experimental, Universidad Nacional de Salta, Salta, Argentina
| | - José L. Zugaza
- Department Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, University of the Basque Country, Bilbao, Spain
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Jean-Paul Dehaye
- Biochemistry and Cellular Biology Laboratory, Institute of Pharmacy C.P. 205/3, Université Libre de Bruxelles, Brussels, Belgium
| | - Aida Marino
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Bilbao, Spain
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Kolodziejczyk-Czepas J, Wachowicz B, Moniuszko-Szajwaj B, Kowalska I, Oleszek W, Stochmal A. Antioxidative effects of extracts from Trifolium species on blood platelets exposed to oxidative stress. J Physiol Biochem 2013; 69:879-87. [PMID: 23749379 DOI: 10.1007/s13105-013-0264-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Accepted: 05/22/2013] [Indexed: 11/25/2022]
Abstract
Clovers (Trifolium) may possess a significant therapeutic potential, but the effects of compounds from these plants on blood platelets and haemostasis have been poorly recognized. The present study was designed to evaluate the antioxidative action of extracts from three species of clovers: Trifolium pratense, Trifolium pallidum and Trifolium scabrum in the protection of human blood platelets in vitro. Platelet suspensions were pre-incubated with crude extract and phenolic fraction of T. pratense or phenolic fractions of T. scabrum and T. pallidum, at the final concentrations of 0.5-50 μg/ml. Then, for the induction of oxidative stress, 100 μM peroxynitrite was added. The antioxidative activity of plant extracts was assessed by measurements of the level of 3-nitrotyrosine, thiol groups and lipid peroxidation products (hydroperoxides and thiobarbituric acid-reactive substances). Despite the significant differences in the composition of the investigated extracts, we observed antioxidative effects of all used mixtures. The presence of Trifolium extracts considerably reduced the peroxynitrite-mediated modifications of proteins and diminished peroxidation of lipids in platelets. Our results indicate on a strong antioxidative activity of the tested extracts-statistically significant effects were found even for the lowest concentrations (0.5 μg/ml) of all extracts. This action may be useful in the protection of blood components, very susceptible to oxidative modifications. The obtained results suggest that the examined clovers are a promising source of compounds, valuable for the protection against oxidative stress-induced damage to blood platelets.
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Affiliation(s)
- Joanna Kolodziejczyk-Czepas
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/3, 90-236, Lodz, Poland,
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Lagarde M, Calzada C, Guichardant M, Véricel E. Dose-effect and metabolism of docosahexaenoic acid: pathophysiological relevance in blood platelets. Prostaglandins Leukot Essent Fatty Acids 2013; 88:49-52. [PMID: 22520055 DOI: 10.1016/j.plefa.2012.04.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Accepted: 04/02/2012] [Indexed: 11/24/2022]
Abstract
Docosahexaenoic acid (DHA) is known as a major nutrient from marine origin. Considering its beneficial effect in vascular risk prevention, the effect of DHA on blood components, especially platelets, will be reviewed here. Investigating the dose-effect of DHA in humans shows that daily intake lower than one gram/day brings several benefits, such as inhibition of platelet aggregation, resistance of monocytes against apoptosis, and reinforced antioxidant status in platelets and low-density lipoproteins. However, higher daily intake may be less efficient on those parameters, especially by losing the antioxidant effect. On the other hand, a focus on the inhibition of platelet aggregation by lipoxygenase end-products of DHA is made. The easy conversion of DHA by lipoxygenases and the formation of a double lipoxygenation product named protectin DX, reveal an original way for DHA to contribute in platelet inhibition through both the cyclooxygenase inhibition and the antagonism of thromboxane A₂ action.
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Affiliation(s)
- M Lagarde
- Université de Lyon, UMR 1060 INSERM CarMeN, IMBL, INSA-Lyon, France.
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16
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Kumari P, Singh RP, Bijo AJ, Reddy CRK, Jha B. Estimation of Lipid Hydroperoxide Levels in Tropical Marine Macroalgae. JOURNAL OF PHYCOLOGY 2012; 48:1362-1373. [PMID: 27009988 DOI: 10.1111/j.1529-8817.2012.01208.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 06/05/2012] [Indexed: 06/05/2023]
Abstract
The incipient levels of lipid hydroperoxides (LHPOs) were determined in selected green, brown, and red macroalgae by the FOX assay using hydroperoxy HPLC mix. The LHPOs contents varied between the investigated species and showed relatively low values in this study. Among the greens, it varied from 12 ± 6.2 μg · g(-1) (Codium sursum) to 31.5 ± 2.8 μg · g(-1) (Ulva lactuca), whereas in reds, from 5.7 ± 1.6 μg · g(-1) (Gracilaria corticata) to 46.2 ± 6 μg · g(-1) (Sarconema filiforme), and in browns, from 4.6 ± 4.4 μg · g(-1) (Dictyota bartayresiana) to 79 ± 5.0 μg · g(-1) (Sargassum tenerrimum), on fresh weight basis. These hydroperoxides represented a minor fraction of total lipids and ranged from 0.04% (S. swartzii) to 1.1% (S. tenerrimum) despite being a rich source of highly unsaturated fatty acids. The susceptibility of peroxidation was assessed by specific lipid peroxidazibility (SLP) values for macroalgal tissues. The LHPO values were found to be independent of both the PUFAs contents and their degree of unsaturation (DBI), as evident from the PCA analysis. SLP values were positively correlated with the LHPOs and negatively with DBI. The FOX assay gave ≥20-fold higher values for LHPOs as compared to the TBARS method for all the samples investigated in this study. Furthermore, U. lactuca cultured in artificial seawater (ASW) enriched with nutrients (N, P, and NP) showed a sharp decline in LHPOs contents relative to those cultured in ASW alone P ≤ 0.05. It is inferred from this study that the FOX assay is an efficient, rapid, sensitive, and inexpensive technique for detecting the incipient lipid peroxidation in macroalgal tissues.
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Affiliation(s)
- Puja Kumari
- Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, Gujarat, India
| | - Ravindra Pal Singh
- Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, Gujarat, India
| | - A J Bijo
- Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, Gujarat, India
| | - C R K Reddy
- Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, Gujarat, India
| | - Bhavanath Jha
- Discipline of Marine Biotechnology and Ecology, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, 364002, Gujarat, India
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17
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Colas R, Sassolas A, Guichardant M, Cugnet-Anceau C, Moret M, Moulin P, Lagarde M, Calzada C. LDL from obese patients with the metabolic syndrome show increased lipid peroxidation and activate platelets. Diabetologia 2011; 54:2931-40. [PMID: 21847583 PMCID: PMC3367234 DOI: 10.1007/s00125-011-2272-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 07/14/2011] [Indexed: 10/17/2022]
Abstract
AIMS/HYPOTHESIS This study assessed oxidative stress in LDL from obese patients with the metabolic syndrome and compared it with that in LDL from type 2 diabetic patients or control volunteers. It also determined the effect on platelets of LDL from the three groups. METHODS The profiles of lipids, fatty acids and fatty acid oxidation products were determined in LDL isolated from plasma of patients with the metabolic syndrome, patients with type 2 diabetes and volunteers (n = 10 per group). The effects of LDL from the participant groups on the platelet arachidonic acid signalling cascade and aggregation were investigated. RESULTS Compared with LDL from control volunteers, LDL from obese metabolic syndrome and type 2 diabetic patients had lower cholesteryl ester, higher triacylglycerol and lower ethanolamine plasmalogen levels. Proportions of linoleic acid were decreased in phosphatidylcholine and cholesteryl esters in LDL from both patient groups. Among the markers of lipid peroxidation, oxidation products of linoleic acid (hydroxy-octadecadienoic acids) and malondialdehyde were increased by 59% and twofold, respectively in LDL from metabolic syndrome and type 2 diabetic patients. LDL from metabolic syndrome and type 2 diabetic patients were equally potent in activating the platelet arachidonic acid signalling cascade through increased phosphorylation of p38 mitogen-activated protein kinase and cytosolic phospholipase A(2), and through increased thromboxane B(2) formation. LDL from patients with the metabolic syndrome and type 2 diabetes potentiated platelet aggregation by threefold and 3.5-fold respectively, whereas control LDL had no activating effects on platelets. CONCLUSIONS/INTERPRETATION The metabolic syndrome in obese patients, without or with diabetes, is associated with increased oxidative stress in LDL, which triggers platelet activation.
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Affiliation(s)
- Romain Colas
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
| | - Agnès Sassolas
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
| | - Michel Guichardant
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
| | | | - Myriam Moret
- Fédération d'endocrinologie
Hospices Civils de LyonBron,FR
| | - Philippe Moulin
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
- Fédération d'endocrinologie
Hospices Civils de LyonBron,FR
| | - Michel Lagarde
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
| | - Catherine Calzada
- CARMEN, Laboratoire de recherche en cardiovasculaire, métabolisme, diabétologie et nutrition
INSERM : U1060INRAInstitut National des Sciences Appliquées de LyonUniversité Claude Bernard - Lyon IHospices Civils de LyonFaculté de Médecine Lyon Sud - BP 12 - 165 Chemin du Grand Revoyet - 69921 Oullins cedex INSA, Bât. IMBL, La Doua - 11 Avenue Jean Capelle - 69621 Villeurbanne Cedex,FR
- * Correspondence should be adressed to: Catherine Calzada
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18
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Lagarde M, Chen P, Véricel E, Guichardant M. Fatty acid-derived lipid mediators and blood platelet aggregation. Prostaglandins Leukot Essent Fatty Acids 2010; 82:227-30. [PMID: 20207119 DOI: 10.1016/j.plefa.2010.02.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Polyunsaturated fatty acids of nutritional value may affect cell functions after their release from cell lipid storage sites, especially phospholipids, and specific oxygenation by cyclooxygenases, lipoxygenases and cytochrome P(450). The end-products, namely prostanoids, leukotrienes, and mono-, di- and tri-hydroxy derivatives exhibit a variety of biological effects, especially on vascular cells, leukocytes and platelets. This paper reviews some results obtained with blood platelets as target cells, showing that various lipoxygenase end-products, mainly mono- and di-hydroxy derivatives, are inhibitors (IC(50) in microM range) of arachidonic acid-induced aggregation either at the cycloxygenase or thromboxane receptor site level.
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Affiliation(s)
- M Lagarde
- Université de Lyon, UMR 870 Inserm/Insa-Lyon, Villeurbanne, France.
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19
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Naseem KM, Bruckdorfer KR. The influence of organic peroxides on platelet aggregation and sensitivity to nitric oxide. Platelets 2010. [DOI: 10.1080/09537109909169178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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RUNX1/core binding factor A2 regulates platelet 12-lipoxygenase gene (ALOX12): studies in human RUNX1 haplodeficiency. Blood 2010; 115:3128-35. [PMID: 20181616 DOI: 10.1182/blood-2009-04-214601] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Haploinsufficiency of RUNX1 (also known as CBFA2/AML1) is associated with familial thrombocytopenia, platelet dysfunction, and predisposition to acute leukemia. We have reported on a patient with thrombocytopenia and impaired agonist-induced aggregation, secretion, and protein phosphorylation associated with a RUNX1 mutation. Expression profiling of platelets revealed approximately 5-fold decreased expression of 12-lipoxygenase (12-LO, gene ALOX12), which catalyzes 12-hydroxyeicosatetraenoic acid production from arachidonic acid. We hypothesized that ALOX12 is a direct transcriptional target gene of RUNX1. In present studies, agonist-induced platelet 12-HETE production was decreased in the patient. Four RUNX1 consensus sites were identified in the 2-kb promoter region of ALOX12 (at -1498, -1491, -708, -526 from ATG). In luciferase reporter studies in human erythroleukemia cells, mutation of each site decreased activity; overexpression of RUNX1 up-regulated promoter activity, which was abolished by mutation of RUNX1 sites. Gel shift studies, including with recombinant protein, revealed RUNX1 binding to each site. Chromatin immunoprecipitation revealed in vivo RUNX1 binding in the region of interest. siRNA knockdown of RUNX1 decreased RUNX1 and 12-LO proteins. ALOX12 is a direct transcriptional target of RUNX1. Our studies provide further proof of principle that platelet expression profiling can elucidate novel alterations in platelets with inherited dysfunction.
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21
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Sill JC, Proper JA, Johnson ME, Uhl CB, Katusic ZS. Reactive oxygen species and human platelet GP IIb/IIIa receptor activation. Platelets 2009; 18:613-9. [DOI: 10.1080/09537100701481385] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Kranzhofer R, Ruef J. Aspirin resistance in coronary artery disease is correlated to elevated markers for oxidative stress but not to the expression of cyclooxygenase (COX) 1/2, a novel COX-1 polymorphism or the PlA1/2polymorphism. Platelets 2009; 17:163-9. [PMID: 16702043 DOI: 10.1080/09537100500441101] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Aspirin resistance (AR) is estimated to be present in 5-75% of patients and is related to increased cardiovascular mortality. However, the underlying mechanisms are mostly unknown. In the present study, AR was detected in 14 out of 55 patients (25%) with coronary artery disease. The presence of concomitant anti-inflammatory drugs did not affect AR. Plasma levels of thromboxane B(2) as well as the markers for oxidative stress and known platelet activators 8-isoprostane and lipid peroxidation products were significantly higher in aspirin-resistant individuals (349.3 pg/ml, 53.9 pg/ml, and 538 micromol/l) compared to controls (113.7 pg/ml, 10.3 pg/ml, and 32.2 micromol/l; P < 0.05, respectively). Platelet cyclooxygenase-1 (COX-1) and COX-2 mRNA and protein expression were without significant differences between the two groups. DNA sequencing detected a novel platelet COX-1 single nucleotide polymorphism (SNP) resulting in amino acid exchange at position 8 (Arg8/Trp8). The wild-type as well as the heterozygous and homozygous SNP were present in both patient groups without significant differences. The aspirin binding (Arg120) and acetylation site (Ser529) were unaffected in the samples tested. Neither was AR related to the platelet integrin PlA(1)/A(2) polymorphism. In conclusion, AR appears to be unrelated to differences in platelet COX-1 and COX-2 expression or to a novel platelet COX-1 SNP and the PlA(1)/A(2) SNP. However, a correlation exists to elevated eicosanoids generated by oxidative stress indicating COX-1-independent pathways for the generation of platelet activating molecules represent a potential cause for AR.
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Affiliation(s)
- Roger Kranzhofer
- Division of Cardiology, University of Heidelberg, Heidelberg, Germany
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23
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Abstract
BACKGROUND Platelets play a role in a number of inflammatory conditions including atherosclerosis; however, the mechanisms of platelet activation under these conditions are unclear. OBJECTIVES To investigate the presence of the vanilloid receptor, TRPV1, which is stimulated by noxious stimuli and by inflammatory mediators, in human platelets. METHODS Platelets loaded with fura-2 or sodium-binding benzofuran isophalate acetoxymethyl ester (SBFI) were used to monitor cytosolic calcium or sodium concentrations. 5-HT secretion was determined by fluorescence assay after conjugation with o-phthaldialdehyde. ATP secretion was determined using luciferin-luciferase. RESULTS TRPV1 was identified by Western blotting using a specific anti-hTRPV1 antibody. The TRPV1 agonist, capsaicin, evoked both Ca(2+) influx and Ca(2+) release from intracellular stores, responses that were blocked in a dose-dependent manner by the TRPV1 antagonists, 5'-Iodo-resiniferatoxin (5'-Iodo-RTX) and AMG 9810. Capsaicin also increased platelet cytosolic [Na(+)]. Capsaicin-evoked Ca(2+) release was abolished in the absence of extracellular Na(+) or by the 5-HT(2A) receptor antagonist, ketanserin. Capsaicin evoked 5-HT release from platelets, a response abolished in the absence of extracellular Na(+) or by 5'-Iodo-RTX. Thus capsaicin-evoked Ca(2+) release appeared to be mediated by Na(+)-dependent 5-HT release. TRPV1-dependent 5-HT release also contributed to ADP- and thrombin-evoked Ca(2+) entry and release. 5'-Iodo-RTX reduced ADP- and thrombin-evoked Ca(2+) signals, effects not additive with those of ketanserin, and 5'-Iodo-RTX inhibited agonist-evoked 5-HT and ATP release. CONCLUSION These results indicate that TRPV1 is present and functionally important in human platelets. The presence of this receptor may provide a link between inflammatory mediators and platelet activation in conditions such as atherosclerosis.
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Affiliation(s)
- A G S Harper
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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24
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Schildknecht S, van der Loo B, Weber K, Tiefenthaler K, Daiber A, Bachschmid MM. Endogenous peroxynitrite modulates PGHS-1-dependent thromboxane A2 formation and aggregation in human platelets. Free Radic Biol Med 2008; 45:512-20. [PMID: 18514074 DOI: 10.1016/j.freeradbiomed.2008.04.042] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Revised: 04/22/2008] [Accepted: 04/29/2008] [Indexed: 01/22/2023]
Abstract
Aggregation of activated platelets is considerably mediated by the autocrine action of thromboxane A2 (TxA2) which is formed in a prostaglandin endoperoxide H2 synthase-1 (PGHS-1 or COX-1)-dependent manner. The activity of PGHS-1 can be stimulated by peroxides, an effect termed "peroxide tone", that renders PGHS-1 the key regulatory enzyme in the formation of TxA2. Activated platelets release nitric oxide (*NO) and superoxide (O*2) but their interactions with the prostanoid pathway have been controversially discussed in platelet physiology and pathophysiology. The current study demonstrates that endogenously formed peroxynitrite at nanomolar concentrations, originating from the interaction of *NO and *O2, potently activated PGHS-1, which parallels TxA2 formation and aggregation in human platelets. Inhibition of the endogenous formation of either *NO or O*2 resulted in a concentration-dependent decline of PGHS-1 activity, TxA2 release, and aggregation. The concept of peroxynitrite as modulator of TxA2 formation and aggregation explains the interaction of *NO and O*2 with the PGHS pathway and suggests a mechanism by which antioxidants can regulate PGHS-1-dependent platelet aggregation. This may provide a molecular explanation for the clinically observed hyperreactivity of platelets in high-risk patients and serve as a basis for novel therapeutic interventions.
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Affiliation(s)
- Stefan Schildknecht
- Vascular Biology Unit, Boston University School of Medicine, Boston, MA, 02118, USA
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25
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Guo Y, Zhang X, Tan W, Miao X, Sun T, Zhao D, Lin D. Platelet 12-lipoxygenase Arg261Gln polymorphism: functional characterization and association with risk of esophageal squamous cell carcinoma in combination with COX-2 polymorphisms. Pharmacogenet Genomics 2007; 17:197-205. [PMID: 17460548 DOI: 10.1097/fpc.0b013e328010bda1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Aberrant arachidonic acid metabolism by 12-lipoxygenase (12-LOX) and cyclooxygenase-2 (COX-2) has been implicated in human carcinogenesis. Inherited polymorphisms in 12-LOX and COX-2 contributed to differential expression or activity of these enzymes might confer interindividual susceptibility to cancer. OBJECTIVE To examine the functional significance of 12-LOX 261 Arg> Gln polymorphism and its association, alone and in combination with COX-2 -1195G > A and -765G > C polymorphisms, with risk of developing esophageal squamous cell carcinoma (ESCC). METHODS The platelet 12-LOX activity was measured by quantifying 12-HETE in the lipoxygenation reaction. Genotypes of 12-LOX261Arg>Gln and COX-2 -1195G>A and -765G>C polymorphisms were determined in a case-control study consisting of 1026 patients and 1270 controls. Associations with the risk of ESCC were estimated by logistic regression. RESULTS Subjects with the 12-LOX Gln/Gln genotype had higher platelet 12-LOX activity (mean+/-SEM nmol/mg/min) than those with the Arg/Arg genotype (0.405+/-0.047 [n=10] versus 0.136+/-0.022 [n=6]; P=0.001). Genotyping data showed that the 12-LOX Gln/Gln genotype was associated with increased risk of developing ESCC (odds ratio [OR]=1.42, 95% confidence interval [CI]=1.12-1.81), compared with the Arg/Arg genotype adjusted for sex, age, and smoking. An increased risk of ESCC was also associated with the COX-2 -1195GA (OR=1.34, 95% CI=1.08-1.68; P=0.008), -1195AA (OR=1.72, 95% CI=1.35-2.20; P=<0.001), and -765GC (OR=2.24, 95% CI=1.59-3.16; P<0.001) genotypes. Furthermore, a multiplicative interaction between the 12-LOX Gln/Gln and COX-2 -1195AA or -765GC genotype in intensifying risk of ESCC was observed, with the ORs for the presence of both 12-LOX Gln/Gln and COX-2 -1195AA or -765GC genotypes being 3.21 (95% CI=1.93-5.34) and 3.33 (95% CI=1.59-6.98). A multiplicative interaction between the -765GC genotype and smoking was also evident (OR=4.45, 95% CI=2.71-7.29). CONCLUSION These observations suggest that inherited polymorphisms in arachidonic acid-metabolizing enzymes, which result in heightened gene expression or enzymatic activity, may confer host susceptibility to ESCC.
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Affiliation(s)
- Yongli Guo
- Department of Etiology, Cancer Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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26
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Chou DS, Hsiao G, Shen MY, Tsai YJ, Chen TF, Sheu JR. ESR spin trapping of a carbon-centered free radical from agonist-stimulated human platelets. Free Radic Biol Med 2005; 39:237-48. [PMID: 15964515 DOI: 10.1016/j.freeradbiomed.2005.03.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2004] [Revised: 02/21/2005] [Accepted: 03/10/2005] [Indexed: 01/14/2023]
Abstract
Several free radical intermediates formed during synthesis of prostaglandin H synthase (PGHS) catalyze the biosynthesis of prostaglandins from arachidonic acid (AA). We attempted to directly detect free radical intermediates of PGHS in cells. Studies were carried out using human platelets, which possess significant PGHS activity. Electron spin resonance (ESR) spectra showed a g = 2.005 signal radical, which was formed by the incubation of collagen, thrombin, AA, and a variety of peroxides with human platelets. The ESR spectra obtained using 5,5-dimethyl-1 pyrroline N-oxide (DMPO) and alpha-phenyl N-tert.-butylnitron (PBN) were typical of an immobilized nitroxide. Extensive Pronase digestion of both the DMPO and PBN adducts allowed us to deduce that it was a carbon-centered radical. The formation of this radical was inhibited by potassium cyanide and by desferroxamine. Peroxides stimulated formation of the g = 2.005 signal radical and inhibited platelet aggregation induced by AA. PGHS cosubstrates increased the intensity of the radical signal but inhibited platelet aggregation induced by AA. Both S-nitro-L-glutathione and reduced glutathione quenched the g = 2.005 radical but could not restore platelet aggregatory activity. These results suggest that the carbon-centered radical is a self-destructing free radical formed during peroxide-mediated deactivation of PGHS in human platelets.
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Affiliation(s)
- Duen-Suey Chou
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan
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27
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Zhao R, Shen GX. Functional modulation of antioxidant enzymes in vascular endothelial cells by glycated LDL. Atherosclerosis 2005; 179:277-84. [PMID: 15777542 DOI: 10.1016/j.atherosclerosis.2004.11.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Revised: 10/20/2004] [Accepted: 11/12/2004] [Indexed: 11/26/2022]
Abstract
Reactive oxygen species (ROS) have been implicated in atherogenesis. Previous studies demonstrated that oxidized LDL (oxLDL) or glycated LDL (gly-LDL) increased the generation of superoxide from vascular endothelial cells (EC). The present study examined the effects of gly-LDL on the activation of antioxidant enzymes for the metabolism of ROS in cultured human vascular endothelial cells in comparison to oxLDL and LDL without chemical modification. Treatment with LDL, oxLDL or gly-LDL significantly increased the release of hydrogen peroxide (H(2)O(2)) from EC following 2h of incubation and the release of superoxide after 24 h of treatment. The increased release of H(2)O(2), but not superoxide, was normalized in EC treated with LDL or its modified forms. Elevated activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase in EC were detected following a 24 h-treatment with the LDLs. The levels of GR activity and reduced/oxidized glutathione (GSH/GSSG) in EC treated with the lipoproteins were increased after 2 h, but were reduced after > or =24 h of incubation. Gly-LDL caused less increases in SOD, GPx or catalase activity, but more evident changes in GR activity and H(2)O(2) release compared to oxLDL or LDL. The findings suggest that exposure to glucose-modified LDL altered the activities of multiple antioxidant enzymes in cultured EC, which partially normalizes the excess generation of ROS, but reduced the intracellular reservoir of GSH.
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Affiliation(s)
- Ruozhi Zhao
- Department of Internal Medicine and Physiology, University of Manitoba, 835-715 McDermot Ave., Winnipeg, Manitoba, Canada R3E 3P4
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28
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Abstract
Hypercholesterolemia is the dominant risk factor associated with atherothrombotic disorders in the western world. Consequently, much attention has been devoted to defining its role in the pathogenesis of atherosclerosis. It is currently recognized that hypercholesterolemia induces phenotypic changes in the microcirculation that are consistent with oxidative and nitrosative stresses. Superoxide is generated via several cellular systems and, once formed, participates in a number of reactions, yielding various free radicals, such as hydrogen peroxide, peroxynitrite, or oxidized low-density lipoproteins. Once oxidant stress is invoked, characteristic pathophysiologic features ensue, such as platelet activation and lipid peroxidation, which are both involved in the initiation and progression of the atherosclerotic lesions. Thus, therapeutic strategies that act to maintain the normal balance in the oxidant status of the vascular bed may prove effective in reducing the deleterious consequences of hypercholesterolemia.
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Affiliation(s)
- Patrizia Ferroni
- Department of Experimental Medicine and Pathology, University La Sapienza, 00161 Rome, Italy
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29
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Coulon L, Calzada C, Moulin P, Véricel E, Lagarde M. Activation of p38 mitogen-activated protein kinase/cytosolic phospholipase A2 cascade in hydroperoxide-stressed platelets. Free Radic Biol Med 2003; 35:616-25. [PMID: 12957654 DOI: 10.1016/s0891-5849(03)00386-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
12-Hydroperoxy-eicosatetraenoic acid (12-HpETE), the main hydroperoxide formed in platelets from arachidonic acid (AA) by 12-lipoxygenase, has been shown to increase the sensitivity of platelets to agonists resulting in increased aggregation. The aim of the present study was to determine the direct effect of low concentrations of 12-HpETE on the signaling pathways leading to AA release from membrane phospholipids and thromboxane A2 (TxA2) formation. Exogenous 12-HpETE activated platelet p38 mitogen-activated protein kinase (p38 MAPK), as assessed by its phosphorylation, at a concentration as low as 100 nM and was much more potent than hydrogen peroxide. Moreover, the incubation of platelets with 100 nM 12-HpETE for 2 min led to the phosphorylation of cytosolic phospholipase A2 (cPLA2). It was associated with a significant decrease in the concentration of AA esterified in phospholipids and an increased concentration of thromboxane B2, the stable catabolite of TxA2. Additionally, decreasing glutathione peroxidase activity pharmacologically favored endogenous 12-HpETE formation and led to an increase in phosphorylated p38 MAPK, while a thiol-reducing agent such as N-acetyl-cysteine fully prevented it. Finally, significant activation of p38 MAPK was also observed in platelets from type 2 diabetic patients with mild hyperglycemia. In conclusion, our data provide a new insight into the mechanism of 12-HpETE-induced platelet priming, suggesting that hydroperoxide-induced p38 MAPK activation could play a relevant role in the exacerbated platelet activation associated with oxidative stress as found in diabetes.
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30
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Lagarde M, Calzada C, Véricel E. Pathophysiologic role of redox status in blood platelet activation. Influence of docosahexaenoic acid. Lipids 2003; 38:465-8. [PMID: 12848295 DOI: 10.1007/s11745-003-1085-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Decrease of platelet glutathione peroxidase activity results in increased life span of lipid hydroperoxides, especially the 12-lipoxygenase product of arachidonic acid, 12-HpETE. Phospholipase A2 activity is subsequently enhanced with the release of arachidonic acid, which results in higher thromboxane formation and platelet function. Docosahexaenoic acid may either potentiate platelet lipid peroxidation or lower it when used at high or low concentrations, respectively. In the case of slowing down lipid peroxidation, docosahexaenoic acid was specifically incorporated in plasmalogen ethanolamine phospholipids. This could have a relevant pathophysiologic role in atherothrombosis.
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Affiliation(s)
- M Lagarde
- UMR 585 INSERM/INSA-Lyon, 69621 Villeurbanne, France.
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31
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Boutaud O, Aronoff DM, Richardson JH, Marnett LJ, Oates JA. Determinants of the cellular specificity of acetaminophen as an inhibitor of prostaglandin H(2) synthases. Proc Natl Acad Sci U S A 2002; 99:7130-5. [PMID: 12011469 PMCID: PMC124540 DOI: 10.1073/pnas.102588199] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acetaminophen has antipyretic and analgesic properties yet differs from the nonsteroidal antiinflammatory drugs and inhibitors of prostaglandin H synthase (PGHS)-2 by exhibiting little effect on platelets or inflammation. We find parallel selectivity at a cellular level; acetaminophen inhibits PGHS activity with an IC(50) of 4.3 microM in interleukin (IL)-1 alpha-stimulated human umbilical vein endothelial cells, in contrast with an IC(50) of 1,870 microM for the platelet, with 2 microM arachidonic acid as substrate. This difference is not caused by isoform selectivity, because acetaminophen inhibits purified ovine PGHS-1 and murine recombinant PGHS-2 equally. We explored the hypothesis that this difference in cellular responsiveness results from antagonism of the reductant action of acetaminophen on the PGHSs by cellular peroxides. Increasing the peroxide product of the PGHS-cyclooxygenase, prostaglandin G(2) (PGG(2)), by elevating the concentration of either enzyme or substrate reverses the inhibitory action of acetaminophen, as does the addition of PGG(2) itself. 12-Hydroperoxyeicosatetraenoic acid (0.3 microM), a major product of the platelet, completely reverses the action of acetaminophen on PGHS-1. Inhibition of PGHS activity by acetaminophen in human umbilical vein endothelial cells is abrogated by t-butyl hydroperoxide. Together these findings support the hypothesis that the clinical action of acetaminophen is mediated by inhibition of PGHS activity, and that hydroperoxide concentration contributes to its cellular selectivity.
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Affiliation(s)
- Olivier Boutaud
- Department of Medicine, Vanderbilt University, Nashville, TN 37232-6602, USA.
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32
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12(S)-Hydroperoxy-eicosatetraenoic acid increases arachidonic acid availability in collagen-primed platelets. J Lipid Res 2001. [DOI: 10.1016/s0022-2275(20)30280-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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33
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Williams JC, Forster LA, Tull SP, Ferns GA. Effects of vitamin E on human platelet and mononuclear cell responses in vitro. Int J Exp Pathol 1999; 80:227-34. [PMID: 10583632 PMCID: PMC2517775 DOI: 10.1046/j.1365-2613.1999.00118.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent epidemiological studies have provided evidence supporting the potential benefits of antioxidants in coronary prevention. We have investigated the effects of vitamin E on platelets, monocytes and endothelial cells in vitro. Pre-incubation of platelets with vitamin E inhibited subsequent thrombin- (P < 0.05, n = 5), collagen- (P < 0. 0001, n = 5) and ADP-(P < 0.05, n = 4) induced platelet aggregation measured using a microtitre plate method, or conventional aggregometry. The adhesion of thrombin-activated platelets to collagen was also inhibited by vitamin E (P < 0.05, n = 8), but not by vitamin C (P > 0.05, n = 8); nor was the adhesion of unstimulated platelets significantly affected (P > 0.05, n = 8). Pre-incubation of monocytes with vitamin E inhibited their subsequent adhesion to plastic (P < 0.05, n = 9), and was also associated with an 18% reduction in adhesion to EA.hy 926 endothelial cells (n = 8), although this failed to reach statistical significance. Pre-incubation of the endothelial cells with vitamin E also significantly reduced subsequent mononuclear cell adhesion by 56% (P < 0.05, n = 3).
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Affiliation(s)
- J C Williams
- Department of Chemical Pathology, Glenfield General Hospital, Leicester
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34
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Calzada C, Véricel E, Mitel B, Lagarde M. Stimulation of platelet aggregation in response to arachidonic acid hydroperoxide via phospholipase activation. Lipids 1999; 34 Suppl:S295. [PMID: 10419183 DOI: 10.1007/bf02562323] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C Calzada
- INSERM U 352, Biochimie et Pharmacologie, INSA-Lyon, Villeurbanne, France.
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35
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Lagarde M, Calzada C, Zakaroff A, Meskini N, Prigent AF, Véricel E. Biological relevance of the 12-lipoxygenase pathway for platelet and lymphocyte functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 447:87-93. [PMID: 10086185 DOI: 10.1007/978-1-4615-4861-4_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- M Lagarde
- INSERM U352, Biochimie & Pharmacologie INSA-Lyon, Villeurbanne, France
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36
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Lagarde M, Lemaitre D, Calzada C, Véricel E. Involvement of lipid peroxidation in platelet signalling. Prostaglandins Leukot Essent Fatty Acids 1997; 57:489-91. [PMID: 9430401 DOI: 10.1016/s0952-3278(97)90433-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A well-known signalling pathway in blood platelets consists in the release of arachidonic acid (AA) from membrane phospholipids and its specific oxygenation into bioactive derivatives. In particular, cyclic prostaglandin endoperoxides and thromboxane A2 are potent inducers of platelet functions and are produced in greater amounts when the level of lipid hydroperoxides is higher than normal, as 'physiological concentrations' of such peroxides activate the cyclooxygenation of AA. In this context, a lower activity of platelet glutathione peroxidase (GPx), the key-enzyme for the degradation of lipid hydroperoxides, has been reported in aging, which will ensure a longer life span to those peroxides. Accordingly, the biosynthesis of pro-aggregatory prostanoids is elevated in platelets from the elderly. On the other hand, fatty acids from marine origin have been recognized as inhibitors of platelet functions, and they may alter the redox status of cells. They may for instance increase the platelet GPx activity, an effect that can be prevented by antioxidants. Overall, these data point out the relevance of the redox status in platelet functions.
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Affiliation(s)
- M Lagarde
- INSERM U352, Biochimie et Pharmacologie INSA-Lyon, Villeurbanne, France
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