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1.
PON1 Q192R is associated with high platelet reactivity with clopidogrel in patients undergoing elective neurointervention: A prospective single-center cohort study.
Tanaka, K, Matsumoto, S, Ainiding, G, Nakahara, I, Nishi, H, Hashimoto, T, Ohta, T, Sadamasa, N, Ishibashi, R, Gomi, M, et al
PloS one. 2021;(8):e0254067
Abstract
BACKGROUND AND PURPOSE The impact of the paraoxonase-1 (PON1) polymorphism, Q192R, on platelet inhibition in response to clopidogrel remains controversial. We aimed to investigate the association between carrier status of PON1 Q192R and high platelet reactivity (HPR) with clopidogrel in patients undergoing elective neurointervention. METHODS Post-clopidogrel platelet reactivity was measured using a VerifyNow® P2Y12 assay in P2Y12 reaction units (PRU) for consecutive patients before the treatment. Genotype testing was performed for PON1 Q192R and CYP2C19*2 and *3 (no function alleles), and *17. PRU was corrected on the basis of hematocrit. We investigated associations between factors including carrying ≥1 PON1 192R allele and HPR defined as original and corrected PRU ≥208. RESULTS Of 475 patients (232 men, median age, 68 years), HPR by original and corrected PRU was observed in 259 and 199 patients (54.5% and 41.9%), respectively. Carriers of ≥1 PON1 192R allele more frequently had HPR by original and corrected PRU compared with non-carriers (91.5% vs 85.2%, P = 0.031 and 92.5% vs 85.9%, P = 0.026, respectively). In multivariate analyses, carrying ≥1 PON1 192R allele was associated with HPR by original (odds ratio [OR] 1.96, 95% confidence interval [CI] 1.03-3.76) and corrected PRU (OR 2.34, 95% CI 1.21-4.74) after adjustment for age, sex, treatment with antihypertensive medications, hematocrit, platelet count, total cholesterol, and carrying ≥1 CYP2C19 no function allele. CONCLUSIONS Carrying ≥1 PON1 192R allele is associated with HPR by original and corrected PRU with clopidogrel in patients undergoing elective neurointervention, although alternative results related to other genetic polymorphisms cannot be excluded.
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2.
Anthocyanins in berries exhibited anti-atherogenicity and antiplatelet activities in a metabolic syndrome population.
Aboonabi, A, Meyer, RR, Gaiz, A, Singh, I
Nutrition research (New York, N.Y.). 2020;:82-93
Abstract
Metabolic syndrome (MetS) is a global challenge for atherosclerosis. It was hypothesized that a four-week consumption of anthocyanin supplements by MetS patients who had three or more risk factors linked with metabolic syndrome would have a greater improvement in cardiometabolic biomarkers and would also reduce the risk of thrombosis. A total of 55 participants in two groups of Normal healthy and MetS (age 25-75y) were given 320 mg anthocyanin supplements twice daily for 4 weeks. Platelet coagulant activities, lipid profiles, fasting blood glucose, and inflammatory and oxidative stress biomarkers were measured before and after supplementation to evaluate the atheroprotective effects of anthocyanins in the study subjects. Four weeks of anthocyanin supplementation significantly decreased cardiometabolic risk factors including the average serum fasting blood glucose (FBG) (by 13.3%, P < .05) and lipid profiles by significant reduction in triglyceride (by 24.9%, P < .05) and LDL-C (by 33.1%, P < .05) in the MetS group. Anthocyanin supplementation also decreased high sensitivity C-reactive protein (hs-CRP) level (by 28%, P < .05) in females. However, no significant differences in serum UA (uric acid) and HDL-C were observed between anthocyanin pre- and post-treatment in both groups. Moreover, Anthocyanin supplements decreased ADP-induced platelet activation configuration expressed as P-selectin by 40% (P < .05). There was a positive correlation between decreased hs-CRP values and the levels of LDL-C and FBG in the MetS group (P < .05). These results support the hypothesis that anthocyanin supplementation exerts anti-atherogenicity effects by improving cardiometabolic risk factors and reducing thrombogenicity in the MetS population.
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3.
Role of platelets in thrombin generation amongst patients with non-transfusion-dependent thalassaemia.
Tan, CW, Wong, WH, Idros, R, Chan, YH, Kaur, H, Tng, ARK, Lee, LH, Ng, HJ, Ang, AL
Annals of hematology. 2019;(4):861-868
Abstract
Non-transfusion-dependent thalassaemia (NTDT) is associated with a hypercoagulable state with thrombotic risk highest after splenectomy. Various mechanisms have been proposed. Although an antiplatelet agent is commonly recommended as thromboprophylaxis in NTDT, the role of platelets contributing to this hypercoagulable state is not well-defined. This study aims to evaluate the role of platelets contributing to hypercoagulability in NTDT patients using thrombin generation (TG). Platelet-rich (PRP) and platelet-poor plasma (PPP) were collected from NTDT patients (n = 30) and normal controls (n = 20) for TG measurement and compared. Controls had higher endogenous thrombin potential (ETP) in PPP (1204.97 nM.min vs 911.62 nM.min, p < 0.001) and PRP (1424.23 nM.min vs 983.99 nM.min, p < 0.001) than patients. Patients' mean normalized ETP ratio [{PRP ETP (patient)/PPP ETP (patient)}/{mean PPP ETP (controls)/mean PPP ETP (controls)}], demonstrated that the presence of platelet does not alter ETP (mean ratio 0.97, 95% CI 0.93-1.02, equivalence defined as 10%). Types of thalassaemia, splenectomy, and severity of liver iron overload did not significantly influence patients' ETP in PPP and PRP by multivariate analysis. Platelets did not increase the TG potential of NTDT patients. Instead of being hypercoagulable, our NTDT patients were hypocoagulable by ETP measurement, although this could not be conclusively demonstrated to correlate with their iron overloading state giving rise to reduced synthesis of coagulation factors. The guideline recommendations for thromboprophylaxis with antiplatelet agents in similar NTDT patients should be re-examined.
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4.
A high glucose level is associated with decreased aspirin-mediated acetylation of platelet cyclooxygenase (COX)-1 at serine 529: A pilot study.
Finamore, F, Reny, JL, Malacarne, S, Fontana, P, Sanchez, JC
Journal of proteomics. 2019;:258-266
Abstract
Diabetes is a major risk factor for cardiovascular diseases. Although aspirin is considered a cornerstone of the prevention and treatment of atherothrombotic-related ischemic events, this antiplatelet drug appears to be less effective in patients with poorly controlled diabetes. It has been suggested that the glycation of platelet proteins plays a pivotal role in poor responsiveness to aspirin. However, a direct effect on the critical residue (serine 529, or Ser 529) of the catalytic pocket of cyclooxygenase 1 (COX-1) has never been demonstrated. This pilot study aimed to elucidate the impact of hyperglycaemia on aspirin acetylation of COX-1 using a targeted mass spectrometry approach. We observed that high glucose concentration had a direct impact on the level of acetylation of the COX-1 Ser 529 residue, whereas it's overall acetylation level remained unchanged. Moreover, the functional aspirin-induced inhibition of COX-1 was dose-dependently impaired as glucose concentrations increased. These in vitro findings were in line with data obtained using platelets from diabetic patients. These data provide new insights into the interplay between glucose and aspirin on platelet proteins and their effects on platelet COX-1. They also suggest a potential mechanistic explanation for the phenomenon of poor response to aspirin in diabetic patients. Data are available via ProteomeXchange with identifier PXD011204. SIGNIFICANCE Deciphering the mutual interplay between glucose and aspirin-mediated acetylation on platelet COX-1, might be of great interest as there is still a lack of information of the mechanism underlying this process that may contribute to the less-than expected response of platelets to aspirin, often observed in diabetes.
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5.
Platelets harbor prostate cancer biomarkers and the ability to predict therapeutic response to abiraterone in castration resistant patients.
Tjon-Kon-Fat, LA, Lundholm, M, Schröder, M, Wurdinger, T, Thellenberg-Karlsson, C, Widmark, A, Wikström, P, Nilsson, RJA
The Prostate. 2018;(1):48-53
Abstract
BACKGROUND Novel therapies for castration resistant prostate cancer (CRPC) have been introduced in the clinic with possibilities for individualized treatment plans. Best practice of those expensive drugs requires predictive biomarker monitoring. This study used circulating biomarker analysis to follow cancer-derived transcripts implicated in therapy resistance. METHOD The isolated platelet population of blood samples and digital-PCR were used to identify selected biomarker transcripts in patients with CRPC prior chemo- or androgen synthesis inhibiting therapy. RESULTS Fifty patients received either docetaxel (n = 24) or abiraterone (n = 26) therapy, with therapy response rates of 54% and 48%, respectively. Transcripts for the PC-associated biomarkers kallikrein-related peptidase-2 and -3 (KLK2, KLK3), folate hydrolase 1 (FOLH1), and neuropeptide-Y (NPY) were uniquely present within the platelet fraction of cancer patients and not detected in healthy controls (n = 15). In the abiraterone treated cohort, the biomarkers provided information on therapy outcome, demonstrating an association between detectable biomarkers and short progression free survival (PFS) (FOLH1, P < 0.01; KLK3, P < 0.05; and NPY, P < 0.05). Patients with biomarker-negative platelets had the best outcome, while FOLH1 (P < 0.05) and NPY (P = 0.05) biomarkers provided independent predictive information in a multivariate analysis regarding PFS. KLK2 (P < 0.01), KLK3 (P < 0.001), and FOLH1 (P < 0.05) biomarkers were associated with short overall survival (OS). Combining three biomarkers in a panel (KLK3, FOLH1, and NPY) made it possible to separate long-term responders from short-term responders with 87% sensitivity and 82% specificity. CONCLUSION Analyzing tumor-derived biomarkers in platelets of CRPC patients enabled prediction of the outcome after abiraterone therapy with higher accuracy than baseline serum PSA or PSA response.
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6.
Effect of Regular Aerobic Activity in Young Healthy Athletes on Profile of Endothelial Function and Platelet Activity.
Podgórska, K, Derkacz, A, Szahidewicz-Krupska, E, Jasiczek, J, Dobrowolski, P, Radziwon-Balicka, A, Skomro, R, Szuba, A, Mazur, G, Doroszko, A
BioMed research international. 2017;:8715909
Abstract
The aim of the study was to assess the impact of regular professional sports activity on the endothelial and platelet function in young men. The studied group were 79 young men (18-40 y, 25 athletes and 54 without any regular physical activity). The nitric oxide (NO) metabolic pathway intermediates, oxidative stress markers, mediators of inflammation, and platelet aggregation were measured. Flow mediated dilation (FMD) was studied before and after intravenous 16,0 g L-arginine infusion, which was repeated after oral administration of acetylsalicylic acid (ASA-75 mg/day) for 4 days. Both groups had similar demographic characteristics. In the athletes, there was significantly higher hsCRP level, better serum lipid profile, and lower pulse pressure. Greater baseline FMD in athletes and in response to L-arginine disappeared following ASA treatment. There were no differences in the levels of the NO pathway metabolites. The control group was characterized by higher PAI-1 following ASA treatment and sICAM-1 both at baseline and after ASA, but no differences in MDA and 6-keto-PGF-1 alpha and platelet aggregation were noted. Regular professional physical activity modulates endothelial but not platelet function and may thus exert an effect on overall cardiovascular risk.
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7.
Randomised, double-blind, placebo-controlled study investigating the effects of inorganic nitrate on vascular function, platelet reactivity and restenosis in stable angina: protocol of the NITRATE-OCT study.
Rathod, KS, Jones, DA, Van-Eijl, TJ, Tsang, H, Warren, H, Hamshere, SM, Kapil, V, Jain, AK, Deaner, A, Poulter, N, et al
BMJ open. 2016;(12):e012728
Abstract
INTRODUCTION The mainstay treatment for reducing the symptoms of angina and long-term risk of heart attacks in patients with heart disease is stent implantation in the diseased coronary artery. While this procedure has revolutionised treatment, the incidence of secondary events remains a concern. These repeat events are thought to be due, in part, to continued enhanced platelet reactivity, endothelial dysfunction and ultimately restenosis of the stented artery. In this study, we will investigate whether a once a day inorganic nitrate administration might favourably modulate platelet reactivity and endothelial function leading to a decrease in restenosis. METHODS AND DESIGN NITRATE-OCT is a double-blind, randomised, single-centre, placebo-controlled phase II trial that will enrol 246 patients with stable angina due to have elective percutaneous coronary intervention procedure with stent implantation. Patients will be randomised to receive 6 months of a once a day dose of either nitrate-rich beetroot juice or nitrate-deplete beetroot juice (placebo) starting up to 1 week before their procedure. The primary outcome is reduction of in-stent late loss assessed by quantitative coronary angiography and optical coherence tomography at 6 months. The study is powered to detect a 0.22±0.55 mm reduction in late loss in the treatment group compared with the placebo group. Secondary end points include change from baseline assessment of endothelial function measured using flow-mediated dilation at 6 months, target vessel revascularisation (TVR), restenosis rate (diameter>50%) and in-segment late loss at 6 months, markers of inflammation and platelet reactivity and major adverse cardiac events (ie, myocardial infarction, death, cerebrovascular accident, TVR) at 12 and 24 months. ETHICS AND DISSEMINATION The study was approved by the Local Ethics Committee (15/LO/0555). Trial results will be published according to the CONSORT statement and will be presented at conferences and reported in peer-reviewed journals. TRIAL REGISTRATION NUMBERS NCT02529189 and ISRCTN17373946, Pre-results.
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8.
Desmopressin improves platelet function in uremic patients taking antiplatelet agents who require emergent invasive procedures.
Kim, JH, Baek, CH, Min, JY, Kim, JS, Kim, SB, Kim, H
Annals of hematology. 2015;(9):1457-61
Abstract
Uremia is associated with platelet dysfunction and can cause a bleeding tendency resulting in a major bleeding event after an invasive procedure or surgery that may be aggravated by antiplatelet agents. We prospectively investigated the potential of desmopressin to improve platelet dysfunction and to lower bleeding risk after emergent invasive procedures in uremic patients taking antiplatelet drugs. Twenty-three patients were enrolled with a mean age of 60.2 ± 11.7 years. Baseline blood urea nitrogen and creatinine were 70.5 ± 29.4 and 10.02 ± 4.52 mg/dL, respectively. Twenty-one patients took aspirin. All patients were infused with desmopressin before their invasive procedures, which were a central catheter insertion for emergent hemodialysis in 13 patients, percutaneous nephrostomy in 7 patients, and angiography through arm or leg vessels in 3 patients. After desmopressin infusion, both the hematocrit and platelet count were slightly decreased without changes in prothrombin time or activated partial thrombin time. Collagen/epinephrine-closure time was significantly shortened from 252.7 ± 40.7 to 144.6 ± 51.0 s (p < 0.001). There were minimal bleeding in 20 patients and mild bleeding in 3 patients. None experienced severe bleeding event or required additional intervention for bleeding control. There were no adverse events including the decrease of serum sodium concentration. In conclusion, a single infusion of desmopressin before invasive procedures in uremic patients on antiplatelet drugs appeared to be well tolerated and improved platelet dysfunction measured by collagen/epinephrine-closure time.
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9.
Electron cryotomography reveals ultrastructure alterations in platelets from patients with ovarian cancer.
Wang, R, Stone, RL, Kaelber, JT, Rochat, RH, Nick, AM, Vijayan, KV, Afshar-Kharghan, V, Schmid, MF, Dong, JF, Sood, AK, et al
Proceedings of the National Academy of Sciences of the United States of America. 2015;(46):14266-71
Abstract
Thrombocytosis and platelet hyperreactivity are known to be associated with malignancy; however, there have been no ultrastructure studies of platelets from patients with ovarian cancer. Here, we used electron cryotomography (cryo-ET) to examine frozen-hydrated platelets from patients with invasive ovarian cancer (n = 12) and control subjects either with benign adnexal mass (n = 5) or free from disease (n = 6). Qualitative inspections of the tomograms indicate significant morphological differences between the cancer and control platelets, including disruption of the microtubule marginal band. Quantitative analysis of subcellular features in 120 platelet electron tomograms from these two groups showed statistically significant differences in mitochondria, as well as microtubules. These structural variations in the platelets from the patients with cancer may be correlated with the altered platelet functions associated with malignancy. Cryo-ET of platelets shows potential as a noninvasive biomarker technology for ovarian cancer and other platelet-related diseases.
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10.
Platelet distribution width and the risk of periprocedural myocardial infarction in patients undergoing percutaneous coronary intervention.
Verdoia, M, Barbieri, L, Schaffer, A, Cassetti, E, Di Giovine, G, Bellomo, G, Marino, P, Sinigaglia, F, De Luca, G
Journal of thrombosis and thrombolysis. 2014;(3):345-52
Abstract
Periprocedural myocardial infarction (PMI) still occurs in a large amount of percutaneous coronary interventions (PCI), mainly due to increased platelet activation. Platelet size has been suggested as an indicator of enhanced reactivity and platelet distribution width (PDW) could reflect morphologic changes in platelets, therefore affecting their function and potentially increasing the risk of complications after coronary stenting. Aim of the present study was to evaluate the relationship between PDW and PMI. We included 1,300 consecutive patients undergoing PCI. Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after PCI. Periprocedural myonecrosis was defined as troponin I increase by three times the ULN or by 50 % of an elevated baseline value, whereas PMI as CKMB increase by three times the ULN or 50 % of baseline. We grouped patients according to tertiles values of PDW (<12.1; ≥13.9). Higher PDW was associated with age (p = 0.03), diabetes (p < 0.001), previous cerebrovascular accidents (p = 0.04), therapy with statins (p = 0.001) and ARBs (p < 0.001), ASA (p = 0.02), nitrates (p = 0.006), calcium antagonists (p = 0.05) and lower pre-procedural clopidogrel bolus (p = 0.005). PDW related with haemoglobin levels (p < 0.001), while inversely to platelet count (p < 0.001) and glycaemia (p = 0.003). Patients with larger PDW had lower presence of coronary thrombus (p < 0.001), higher rate of coronary calcifications (p = 0.02), higher stenting rate (p = 0.03) and lower rate of distal embolization (p = 0.03). Larger PDW did not increase risk of PMI (p = 0.11; adjusted OR [95 % CI] = 0.94 [0.78-1.1], p = 0.55) or periprocedural myonecrosis (p = 0.73; adjusted OR [95 % CI] = 0.95 [0.82-1.1], p = 0.51). Results were confirmed even in higher-risk subgroups of patients. In patients undergoing coronary stenting, PDW does not increase the risk of periprocedural MI and therefore should not be considered a risk factor for thrombotic periprocedural complications after PCI.