A Thrombelastograph whole blood assay for clinical monitoring of NSAID-insensitive transcellular platelet activation by arachidonic acid (original) (raw)
Related papers
Drug/drug interaction of common NSAIDs with antiplatelet effect of aspirin in human platelets
European Journal of Pharmacology, 2013
Nonsteroidal anti-inflammatory drugs (NSAIDs) may interfere with the anti-platelet activity of aspirin at the level of the platelet cyclooxygenase-1 (COX-1) enzyme. In order to examine the interference of common NSAIDs with the anti-platelet activity of aspirin the human platelet rich plasma from voluntary donors was used for arachidonic acid-induced aggregation and determination of thromboxane synthesis. Further, docking studies were used to explain the molecular basis of the NSAID/aspirin interaction. The experimental results showed that celecoxib, dipyrone (active metabolite), ibuprofen, flufenamic acid, naproxen, nimesulide, oxaprozin, and piroxicam significantly interfere with the anti-platelet activity of aspirin, while diclofenac, ketorolac and acetaminophen do not. Docking studies suggested that NSAIDs forming hydrogen bonds with Ser530, Arg120, Tyr385 and other amino acids of the COX-1 hydrophobic channel interfere with antiplatelet activity of aspirin while non interfering NSAIDs do not form relevant hydrogen bond interactions within the aspirin binding site. In conclusion, docking analysis of NSAID interactions at the COX-1 active site appears useful to predict their interference with the anti-platelet activity of aspirin. The results, demonstrate that some NSAIDs do not interfere with the antiplatelet action of aspirin while many others do and provide a basis for understanding the observed differences among individual non-aspirin NSAIDs.
Thrombosis and Haemostasis, 2012
SummaryInhibition of platelet function by aspirin results from irreversible inhibition of platelet cyclooxygenase (COX)-1. While sufficient inhibition is obtained at antiplatelet doses (75–325 mg/day) in most (≥95%) treated patients, the antiplatelet effect of aspirin and subsequent cardiovascular risk reduction is much less in clinical settings and disease-dependent. Several reasons for this “high on treatment platelet reactivity” are known. This paper reviews the evidence for an interaction between aspirin and other COX inhibitors, namely non-steroidal antiinflammatory drugs (NSAIDs). Numerous experimental studies demonstrated a pharmacodynamic interaction between aspirin and NSAIDs. This likely occurs within the hydrophobic substrate channel of platelet COX-1 and might be explained by molecular competition between inhibitor drugs and substrate (arachidonic acid) at overlapping binding sites. This interaction is found with some compounds, notably ibuprofen and dipyrone (metamizole...
British Journal of Clinical Pharmacology, 1991
1 Four healthy male subjects received racemic ibuprofen (200, 400, 800 and 1200 mg), orally, on four occasions, 2 weeks apart, according to a four-way Latin-square design, in order to investigate the influence of increasing dose of ibuprofen on the magnitude and duration of its antiplatelet effect as well as on the relationship between such effect and drug concentration. 2 The antiplatelet effect of ibuprofen was assessed by measuring the inhibition of platelet thromboxane B2 (TXB2) generation during the controlled clotting of whole blood. The plasma unbound concentration of S(+)-ibuprofen, the enantiomer shown in an in vitro study to be responsible for the inhibitory effect of platelet TXB2 generation, was measured using an enantioselective method. 3 The maximum percentage inhibition of TXB2 generation increased significantly with dose from a mean ± s.d. of 93.4 ± 1.2% after the 200 mg dose to 98.8 ± 0.3% after the 1200 mg dose, and there was an increase with dose in the duration of inhibition of TXB2 generation. The effect of ibuprofen on platelet TXB2 generation was transient and mirrored the time-course of unbound S(+)-ibuprofen in plasma; on all but one of the 16 occasions, serum TXB2 concentrations returned to at least within 10% of the pretreatment concentrations within 24 h of ibuprofen administration. 4 For each subject, the relationship between the percentage inhibition of TXB2 generation and the unbound concentration of S(+)-ibuprofen in plasma was modelled according to a sigmoidal Emax equation. The mean plasma unbound concentration of S(+)-ibuprofen required to inhibit platelet TXB2 generation by 50% (EC50) was 9.8 + 1.0 ±g F'. 5 The results indicate that the intensity and duration of the antiplatelet effect of ibuprofen were dose-dependent. The antiplatelet effect was related to the plasma unbound concentration of S(+)-ibuprofen and the small degree of interindividual variability in the EC50 values suggests similar sensitivity among the subjects of platelet cyclo-oxygenase to the inhibitory action of S(+)-ibuprofen.
Comparison of the effects of ketoprofen on platelet function in the presence and absence of aspirin
The American Journal of Medicine, 2001
Although aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) exert inhibitory effects on platelets in vitro and in vivo, there are insufficient data to substantiate the use of NSAIDs alone as antiplatelet drugs in patients already taking aspirin. We therefore sought to determine whether aspirin, added to NSAID therapy, further suppresses platelet function.
Journal of inflammation (London, England), 2014
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. 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). Low-dose aspirin administration not only inhibited TxA2 generation but also decreased the production of ...
Proceedings of the National Academy of Sciences, 2014
The cardiovascular safety of nonsteroidal antiinflammatory drugs (NSAIDs) may be influenced by interactions with antiplatelet doses of aspirin. We sought to quantitate precisely the propensity of commonly consumed NSAIDs—ibuprofen, naproxen, and celecoxib—to cause a drug-drug interaction with aspirin in vivo by measuring the target engagement of aspirin directly by MS. We developed a novel assay of cyclooxygenase-1 (COX-1) acetylation in platelets isolated from volunteers who were administered aspirin and used conventional and microfluidic assays to evaluate platelet function. Although ibuprofen, naproxen, and celecoxib all had the potential to compete with the access of aspirin to the substrate binding channel of COX-1 in vitro, exposure of volunteers to a single therapeutic dose of each NSAID followed by 325 mg aspirin revealed a potent drug-drug interaction between ibuprofen and aspirin and between naproxen and aspirin but not between celecoxib and aspirin. The imprecision of estimates of aspirin consumption and the differential impact on the ability of aspirin to inactivate platelet COX-1 will confound head-to-head comparisons of distinct NSAIDs in ongoing clinical studies designed to measure their cardiovascular risk.
Interactions between aspirin and COX-2 inhibitors or NSAIDs in a rat thrombosis model
Fundamental and Clinical Pharmacology, 2004
The possible prothrombotic effect of selective inhibitors of cyclo-oxygenase 2 (COX-2) and the possible interaction between aspirin used at cardioprotective doses and COX-2 selective or non-selective NSAIDs have been the object of much recent debate: during the VIGOR study comparing rofecoxib and naproxen [1] in patients with rheumatoid arthritis, there was an apparent doubling of the risk of myocardial infarction in the rofecoxib-treated patients, compared with the patients in the naproxen arm. This was not found in the CLASS trial comparing celecoxib and ibuprofen or diclofenac [2] in patients with osteoarthritis or rheumatoid arthritis. Concerns were raised about the cardiac safety of COX-2 inhibitors [3].
Faseb Journal, 2006
Recent data have suggested that regular consumption of nonsteroid anti-inflammatory drugs (NSAIDs), particularly selective inhibitors of cyclooxygenase-2 (COX-2), is associated with an increased risk of thrombotic events. It has been suggested that this is due to NSAIDs reducing the release from the endothelium of the antithrombotic mediator prostaglandin I 2 as a result of inhibition of endothelial COX-2. Here, however, we show that despite normal human vessels and endothelial cells containing cyclooxygenase-1 (COX-1) without any detectable COX-2, COX-1 in vessels or endothelial cells is more readily inhibited by NSAIDs and COX-2-selective drugs than COX-1 in platelets (e.g., log IC 50 ؎SEM values for endothelial cells vs. platelets: naproxen -5.59؎0.07 vs. -4.81؎0.04; rofecoxib -4.93؎0.04 vs. -3.75؎0.03; n.)7؍ In broken cell preparations, the selectivities of the tested drugs toward endothelial cell over platelet COX-1 were lost. These observations suggest that variations in cellular conditions, such as endogenous peroxide tone and substrate supply, and not the isoform of cyclo-oxygenase present, dictate the effects of NSAIDs on endothelial cells vs. platelets. This may well be because the platelet is not a good representative of COX-1 activity within the body as it produces prostanoids in an explosive burst that does not reflect tonic release from other cells. The results reported here can offer an explanation for the apparent ability of NSAIDs and COX-2-selective inhibitors to increase the risk of myocardial infarction and stroke.-Mitchell, J. A., Lucas, R., Vojnovic, I., Hasan, K., Pepper, J. R., Warner, T. D. Stronger inhibition by nonsteroid anti-inflammatory drugs of cyclooxygenase-1 in endothelial cells than platelets offers an explanation for increased risk of thrombotic events. FASEB J. 20, 2468 -2475 (2006)
Journal of the American College of Cardiology, 2009
This study was conducted to assess the thromboxane (TX) dependence of biochemical and functional indexes used to monitor the effect of low-dose aspirin. Functional assays of the antiplatelet effects of low-dose aspirin variably reflect the TX-dependent component of platelet aggregation. Previous studies of aspirin resistance were typically based on a single determination of platelet aggregation. We assessed the TXB(2) dependence of biochemical and functional indexes, as well as their intersubject and intrasubject variability during administration of the drug and after its withdrawal in 48 healthy volunteers randomized to receive aspirin 100 mg daily for 1 to 8 weeks. Serum TXB(2) was uniformly suppressed by 99% of baseline. Urinary 11-dehydro-TXB(2), arachidonic acid-induced aggregation, and VerifyNow Aspirin (Accumetrics Inc., San Diego, California) showed stable, incomplete inhibition (65%, 80%, and 35%, respectively). Adenosine diphosphate- and collagen-induced aggregation was hi...
Background-The antiplatelet effect of aspirin is attributed to platelet cyclooxygenase-1 inhibition. Controversy exists on the prevalence of platelet resistance to aspirin in patients with coronary artery disease and effects of aspirin dose on inhibition. Our primary aim was to determine the degree of platelet aspirin responsiveness in patients, as measured by commonly used methods, and to study the relation of aspirin dose to platelet inhibition. Methods and Results-We prospectively studied the effect of aspirin dosing on platelet function in 125 stable outpatients with coronary artery disease randomized in a double-blind, double-crossover investigation (81, 162, and 325 mg/d for 4 weeks each over a 12-week period). At all doses of aspirin, platelet function was low as indicated by arachidonic acid (AA)-induced light transmittance aggregation, thrombelastography, and VerifyNow. At any 1 dose, resistance to aspirin was 0% to 6% in the overall group when AA was used as the agonist, whereas it was 1% to 27% by other methods [collagen and ADP-induced light transmittance aggregation, platelet function analyzer (PFA-100)]. Platelet response to aspirin as measured by collagen-induced light transmittance aggregation, ADP-induced light transmittance aggregation, PFA-100 (81 mg versus 162 mg, PՅ0.05), and urinary 11-dehydrothromboxane B 2 was dose-related (81 mg versus 325 mg, Pϭ0.003). No carryover effects were observed. Conclusions-The assessment of aspirin resistance is highly assay-dependent; aspirin is an effective blocker of AA-induced platelet function at all doses, whereas higher estimates of resistance were observed with methods that do not use AA as the stimulus. The observation of dose-dependent effects despite nearly complete inhibition of AA-induced aggregation suggests that aspirin may exert antiplatelet properties through non-cyclooxygenase-1 pathways and deserves further investigation. (Circulation. 2007;115:3156-3164.)