Background: Aspirin, a commonly used antiplatelet agent, blocks platelet thromboxane A₂ (TXA₂) formation from arachidonic acid (AA) by acetylating platelet cyclooxygenase-1 (COX-1). Laboratory methods currently used to detect this antiplatelet effect of aspirin provide variable results. We have reported three methods that assess platelet COX-1 acetylation (inactivation) by aspirin and its direct consequences. The first and second assays use monoclonal anti-human-COX-1 antibodies that only detect acetylated (inactivated) COX-1 and active (non-acetylated) COX-1, respectively. The third method measures platelet production of TXB₂ (the stable metabolite of TXA₂) in vitro in response to AA. We compared the results of these three reference methods with other routinely used methods for assessing the functional consequences aspirin treatment.
Methods: 108 healthy volunteers were treated with low-dose aspirin for 7 days. On day 7 following aspirin treatment COX-1 in the platelets was fully acetylated whereas only non-acetylated COX-1 was present in the day 0 platelets. Further, TXB2 production by day 7 platelets was completely blocked. The following tests were performed on the samples obtained from study participants before and after seven days of aspirin treatment: PFA-100 closure time with collagen/epinephrine cartridge, VerifyNow (VN) Aspirin Assay, platelet aggregation and ATP secretion using AA, ADP, epinephrine and collagen as agonists.
Results: Comparing the pre-treatment and day 7 values, methods that use AA as platelet agonist (AA-induced platelet aggregation/secretion and VN Aspirin Assay) showed high discriminative power. In contrast, results of the other tests showed considerable overlap between day 7 and day 0 values.
Conclusions: Only assays that clearly distinguish between acetylated and non-acetylated platelet COX-1 are useful for establishing the antiplatelet effect of aspirin. The other tests are not suitable for this purpose.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.thromres.2013.10.008 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Development and validation of a five-year cardiovascular risk assessment tool for Asian adults aged 75 years and older.
BMC Geriatr
January 2025
Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, No. 33, Linsen S. Rd., Zhongzheng Dist., Taipei, 100025, Taiwan.
Background: To identify cardiovascular (CV) risk factors in Asian elderly aged 75 years and older and subsequently develop and validate a sex-specific five-year CV risk assessment tool for this population.
Methods: This study included 12,174 patients aged ≥ 75 years without a prior history of cardiovascular disease at a single hospital in Taiwan. Electronic health records were linked to the National Health Insurance Research Database and the National Death Registry to ensure comprehensive health information.
Long-term risk of adverse limb outcomes in older patients after endovascular femoral artery revascularization: The Boston femoral artery endovascular revascularization outcomes (Boston FAROUT) study.
Cardiovasc Revasc Med
December 2024
Veterans Affairs Boston Healthcare System, West Roxbury, MA, United States of America; Brigham and Women's Hospital, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America. Electronic address:
Introduction: Older patients may be denied endovascular revascularization of the superficial femoral artery (SFA) for peripheral artery disease (PAD) due to concerns of worse limb outcomes than younger patients.
Methods: We assessed adverse outcomes in patients after an index revascularization stratified by age (age < 65, 65-75 years, and > 75 years) from two centers between 2003 and 2011 and followed a median 9 (25 %-75 %: 7, 11) years. Outcomes included major adverse limb events (MALE) or minor repeat revascularization, death, and major adverse cardiac and cerebrovascular events (MACCE).
Prostanoids and Heart Failure: Friend or Foe?
J Am Coll Cardiol
January 2025
Department of Cardiology, British Heart Foundation Cardiovascular Research Centre, School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, Lanarkshire, United Kingdom. Electronic address:
Association of Systemic Thromboxane Generation With Risk of Developing Heart Failure.
J Am Coll Cardiol
January 2025
Division of Biostatistics and Health Services Research, Department of Population and Quantitative Health Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA.
Background: Systemic thromboxane A generation, which is readily assessed by quantifying thromboxane B metabolites (TXB-M) in the urine, is associated with impaired cardiac performance and mortality in aspirin (ASA) users with heart failure (HF).
Objectives: This study sought to determine the association of urinary TXB-M with the risk of developing HF in individuals without prior history of HF and with normal left ventricular function irrespective of ASA use.
Methods: Urine TXB-M were measured by immunoassay and adjusted to urine concentration and renal function (TXB-M) in 2,611 Framingham Heart Study participants (54.
Comparing Efficacy of Steroid Irrigation + Steroid-eluting Sinus Stent Versus Steroid Irrigation Alone for Maintaining Frontal Sinus Patency After Sinus Surgery: A Randomized Controlled Trial.
Int Forum Allergy Rhinol
January 2025
Department of Otolaryngology, Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, USA.
Background: Steroid rinses and steroid-eluting stents are both options for preventing postoperative stenosis after frontal sinus surgery. This study aimed to assess whether steroid-eluting stents offer added benefit over steroid rinses alone in postoperative healing and long-term frontal sinus patency.
Methods: A randomized controlled trial enrolled patients with CRS with nasal polyps (CRSwNP) who underwent surgery for bilateral and equal frontal sinusitis after failing prior medical therapy.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!