RESUMO
Background: Variations in several clopidogrel-pharmacogenes have been linked to clopidogrel response variability and clinical outcomes. We aimed to determine the frequency distribution of major polymorphisms on CYP2C19, PON1, ABCB1 and P2RY12 pharmacogenes in Puerto Ricans. Methods: This was a cross-sectional, population-based study of 200 unrelated "Guthrie" cards specimens from newborns registered in the Puerto Rican newborn screening program (PRNSP) between 2004 and 2014. Taqman® SNP assay techniques were used for genotyping. Results: Minor allele frequencies (MAF) were 46% for PON1 (rs662), 41% for ABCB1 (rs1045642), 14% for CYP2C19*17, 13% for CYP2C19*2, 12% for P2RY12-H2 and 0.3% for CYP2C19*4. No carriers of the CYP2C19*3 variants were detected. All alleles and genotype proportions were found to be in Hardyâ»Weinberg equilibrium (HWE). Overall, there were no significant differences between MAFs of these variants in Puerto Ricans and the general population (n = 453) of the 1000 Genome project, except when comparisons to each individual parental group were performed (i.e., Africans, Europeans and East-Asians; p < 0.05). As expected, the prevalence of these markers in Puerto Ricans most resembled those in the 181 subjects from reference populations of the Americas. Conclusions: These prevalence data provide a necessary groundwork for future clinical studies of clopidogrel pharmacogenetics in Caribbean Hispanics.
Assuntos
Arildialquilfosfatase/genética , Clopidogrel/farmacologia , Citocromo P-450 CYP2C19/genética , Inibidores da Agregação Plaquetária/farmacologia , Polimorfismo de Nucleotídeo Único , Receptores Purinérgicos P2Y12/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Clopidogrel/farmacocinética , Estudos Transversais , Feminino , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Recém-Nascido , Masculino , Triagem Neonatal , Farmacogenética , Inibidores da Agregação Plaquetária/farmacocinética , Porto RicoRESUMO
Adenine nucleotides through P2Y1 receptor stimulation are known to control retinal progenitor cell (RPC) proliferation by modulating expression of the p57KIP2, a cell cycle regulator. However, the role of Gi protein-coupled P2Y12 and P2Y13 receptors also activated by adenine nucleotides in RPC proliferation is still unknown. Gene expression of the purinergic P2Y12 subtype was detected in rat retina during early postnatal days (P0 to P5), while expression levels of P2Y13 were low. Immunohistochemistry assays performed with rat retina on P3 revealed P2Y12 receptor expression in both Ki-67-positive cells in the neuroblastic layer and Ki-67-negative cells in the ganglion cell layer and inner nuclear layer. Nonetheless, P2Y13 receptor expression could not be detected in any stratum of rat retina. Intravitreal injection of PSB 0739 or clopidogrel, both selective P2Y12 receptor antagonists, increased by 20 and 15%, respectively, the number of Ki-67-positive cells following 24 h of exposure. Moreover, the P2Y12 receptor inhibition increased cyclin D1 and decreased p57KIP2 expression. However, there were no changes in the S phase of the cell cycle (BrdU-positive cells) or in mitosis (phospho-histone-H3-positive cells). Interestingly, an increase in the number of cyclin D1/TUNEL-positive cells after treatment with PSB 0739 was observed. These data suggest that activation of P2Y12 receptors is required for the successful exit of RPCs from cell cycle in the postnatal rat retina.
Assuntos
Organogênese , Receptores Purinérgicos P2Y12/metabolismo , Receptores Purinérgicos P2/metabolismo , Retina/metabolismo , Animais , Animais Recém-Nascidos , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Ratos , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2Y12/genética , Células-Tronco/citologia , Células-Tronco/metabolismoRESUMO
BACKGROUND: Antiplatelet therapy with clopidogrel is recommended to reduce cardiovascular events in patients with peripheral artery disease (PAD); however, clopidogrel efficacy has not been adequately studied in this patient population. Therefore, we aimed to determine the effects of cilostazol therapy on platelet reactivity among PAD patients on clopidogrel. METHODS: We performed a cross-sectional pilot study of 46 Puerto Rican patients diagnosed with PAD. The cohort was divided based on use of clopidogrel and cilostazol (n=24) or clopidogrel alone (n=22). Platelet function was measured ex vivo using the VerifyNow P2Y12 assay. Genomic DNA was extracted from peripheral blood samples using the QIAamp DNA Blood Midi Kit, which was subjected to candidate variant genotyping (CYP2C19, ABCB1, PON1 and P2RY12) using TaqMan quantitative polymerase chain reaction assays. All analyses were performed using SAS version 9.4 (SAS Institute). RESULTS: Among all enrolled patients, 18 (39%) had high on-treatment platelet reactivity (HTPR). The mean platelet reactivity was 207±53 (range, 78-325) with higher P2Y12 reaction units in the non-cilostazol group, 224±45 vs. 191±55 on the cilostazol group (p=0.03). No significant differences were observed in the clinical or genetic variables between the two groups. A multiple regression analysis determined that history of diabetes mellitus (p=0.03), use of cilostazol (p=0.03) and hematocrit (p=0.02) were independent predictors of platelet reactivity. CONCLUSIONS: In Puerto Rican PAD patients on clopidogrel therapy, history of diabetes mellitus, use of cilostazol and hematocrit are independent predictors of platelet reactivity. Adjunctive cilostazol therapy may enhance clopidogrel efficacy among PAD patients with HTPR.
Assuntos
Plaquetas/efeitos dos fármacos , Doença Arterial Periférica/complicações , Doença Arterial Periférica/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Tetrazóis/farmacologia , Ticlopidina/análogos & derivados , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Idoso , Arildialquilfosfatase/genética , Cilostazol , Clopidogrel , Estudos Transversais , Citocromo P-450 CYP2C19 , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Projetos Piloto , Testes de Função Plaquetária , Receptores Purinérgicos P2Y12/genética , Tetrazóis/uso terapêutico , Ticlopidina/farmacologia , Ticlopidina/uso terapêuticoRESUMO
Identifying new target molecules through which eosinophils secrete their stored proteins may reveal new therapeutic approaches for the control of eosinophilic disorders such as host immune responses to parasites. We have recently reported the expression of the purinergic P2Y12 receptor (P2Y12R) in human eosinophils; however, its functional role in this cell type and its involvement in eosinophilic inflammation remain unknown. Here, we investigated functional roles of P2Y12R in isolated human eosinophils and in a murine model of eosinophilic inflammation induced by Schistosoma mansoni (S. mansoni) infection. We found that adenosine 5'-diphosphate (ADP) induced human eosinophils to secrete eosinophil peroxidase (EPO) in a P2Y12R dependent manner. However, ADP did not interfere with human eosinophil apoptosis or chemotaxis in vitro. In vivo, C57Bl/6 mice were infected with cercariae of the Belo Horizonte strain of S. mansoni. Analyses performed 55 days post infection revealed that P2Y12R blockade reduced the granulomatous hepatic area and the eosinophilic infiltrate, collagen deposition and IL-13/IL-4 production in the liver without affecting the parasite oviposition. As found for humans, murine eosinophils also express the P2Y12R. P2Y12R inhibition increased blood eosinophilia, whereas it decreased the bone marrow eosinophil count. Our results suggest that P2Y12R has an important role in eosinophil EPO secretion and in establishing the inflammatory response in the course of a S. mansoni infection.
Assuntos
Eosinófilos/metabolismo , Receptores Purinérgicos P2Y12/metabolismo , Schistosoma mansoni/patogenicidade , Difosfato de Adenosina/farmacologia , Animais , Células da Medula Óssea/citologia , Sobrevivência Celular/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Peroxidase de Eosinófilo/metabolismo , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Humanos , Inflamação , Interleucina-13/análise , Interleucina-13/sangue , Interleucina-4/análise , Interleucina-4/sangue , Fígado/metabolismo , Fígado/parasitologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Purinérgicos P2Y12/química , Receptores Purinérgicos P2Y12/genética , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/patologia , Células Th2/imunologiaRESUMO
We investigated the correlation between genetic polymorphisms of cytochrome P450 enzyme genes and the outcome of clopidogrel treatment in 118 coronary disease patients after percutaneous coronary intervention at the Chinese PLA General Hospital. Patients were divided into an ischemia event relapse group (IERG) and a non-IERG group (NIERG) based on relapse of ischemia events within 6 months after percutaneous coronary intervention. Ischemia occurred in 26.27% of patients. Thromboelastogram platelet mapping results showed that compared with the NIERG, the ADP-induced platelet inhibition ratio in the IERG was significantly lower (31.33 ± 24.91% vs 54.68 ± 26.63%, P < 0.05). The platelet inhibition ratio of patients carrying mutant alleles CYP3A5*3 (41.98 ± 29.33% vs 52.89 ± 26.49%), CYP2C19*2 (43.15 ± 27.97% vs 55.89 ± 26.71%), and P2Y12*1 (38.74 ± 24.36% vs 52.19 ± 28.58%) was lower than patients with the wild-type alleles. The frequency of ischemia event relapse in patients with the mutant alleles CYP3A5*3 and CYP2C19*2 was significantly higher than patients carrying the G/G genotype; however, there was no significant difference between patients carrying the T/T genotype and C allele of P2Y12*1. Thus, coexisting polymorphisms of CYP3A5*3 and 2C19*2, but not P2Y12*1, play an important role in the variability of clopidogrel's curative effect.
Assuntos
Plaquetas/efeitos dos fármacos , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP3A/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Receptores Purinérgicos P2Y12/genética , Ticlopidina/análogos & derivados , Difosfato de Adenosina/química , Adulto , Idoso , Alelos , Coagulação Sanguínea , Plaquetas/citologia , China , Clopidogrel , Feminino , Genótipo , Humanos , Isquemia/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mutação , Intervenção Coronária Percutânea , Farmacogenética , Polimorfismo Genético , Medicina de Precisão , Recidiva , Tromboelastografia , Ticlopidina/uso terapêuticoRESUMO
The aim of the present study was to establish the gene frequency of six polymorphisms of the ABCB1, CYP3A5, CYP2C19, and P2RY12 genes in a population resident of Mexico City. The proteins encoded by these genes have been associated with the absorption, and biotransformation of clopidogrel. The ABCB1 T3435C, CYP3A5 V3 A6986G, P2RY12 G52T, P2RY12 C34T, CYP2C19 V2 and V3 (positions G681A and G636A, respectively), polymorphisms were analyzed by 5' exonuclease TaqMan genotyping assays in a group of 269 healthy unrelated Mexican Mestizo individuals. The CYP2C19 V3 G636A polymorphism was not detected in the Mexican Mestizos population. However, the studied population presented significant differences (P < 0.05) in the distribution of the T3435C, A6986G, G681A, G52T and C34T polymorphisms when compared to reported frequencies of Amerindian of South America, Caucasian, Asian, and African populations. In summary, the distribution of the ABCB1, CYP3A5, CYP2C19, and P2RY12 gene polymorphisms distinguishes to the Mexican Mestizos population from other ethnic groups.
Assuntos
Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP3A/genética , Etnicidade/genética , Receptores Purinérgicos P2Y12/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Alelos , Feminino , Frequência do Gene , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , México , Polimorfismo GenéticoRESUMO
INTRODUCTION: Clopidogrel is recommended in addition to aspirin to prevent atherothrombotic events in patients with acute coronary syndromes (ACS) and in those undergoing percutaneous coronary intervention (PCI). However, an interindividual variability in platelet inhibition response to clopidogrel has been demonstrated, and is associated with recurrent cardiovascular events. Multiple mechanisms have been associated with no response including genetics factors. MATERIALS AND METHODS: The present study enrolled 60 patients with ACS undergoing emergent PCI. Platelet aggregation to adenosine diphosphate and arachidonic acid was assessed by turbidimetric method at 24 hours after dual administration of 300 mg of clopidogrel and 300 mg of acetylsalicylic acid loading dose. Clopidogrel or acetylsalicylic acid resistance was defined by persistence of Platelet Reactivity (PR=ADP-Ag >70% or PR=Arachidonic Acid-Ag>20%) respectively. The CYP3A51*/5*, PIA1/A2, and T744C polymorphisms were determined in all participants by PCR-RFLP. RESULTS: The allelic frequencies were: CYP3A5*3 (71.65%), PIA2 (10.8%), and 744 C (15.0%). We founded high percent of clopidogrel resistance (60.0%), compared with 8.3% of acetylsalicylic acid in those patients. The genotype frequencies of those polymorphisms were similar between responders and non responders defined by PR. There was a high percent of coronary adverse events. CONCLUSIONS: We identified a high percent of clopidogrel resistance in Mexican patients with ACS undergoing PCI. However, a normal platelet response to acetylsalicylic acid was observed in most of them. There was no association between CYP3A5*1/*3, PIA1/A2, and T744C polymorphisms and clopidogrel resistance. More studies are needed to determine the possible interaction between genetics factors, platelet response to clopidogrel and cardiovascular adverse events.