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1.
Am J Hum Genet ; 110(1): 58-70, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36608685

RESUMO

Expression quantitative locus (eQTL) studies have paved the way in identifying genetic variation impacting gene expression levels. African Americans (AAs) are disproportionately underrepresented in eQTL studies, resulting in a lack of power to identify population-specific regulatory variants especially related to drug response. Specific drugs are known to affect the biosynthesis of drug metabolism enzymes as well as other genes. We used drug perturbation in cultured primary hepatocytes derived from AAs to determine the effect of drug treatment on eQTL mapping and to identify the drug response eQTLs (reQTLs) that show altered effect size following drug treatment. Whole-genome genotyping (Illumina MEGA array) and RNA sequencing were performed on 60 primary hepatocyte cultures after treatment with six drugs (Rifampin, Phenytoin, Carbamazepine, Dexamethasone, Phenobarbital, and Omeprazole) and at baseline (no treatment). eQTLs were mapped by treatment and jointly with Meta-Tissue. We found varying transcriptional changes across different drug treatments and identified Nrf2 as a potential general transcriptional regulator. We jointly mapped eQTLs with gene expression data across all drug treatments and baseline, which increased our power to detect eQTLs by 2.7-fold. We also identified 2,988 reQTLs (eQTLs with altered effect size after drug treatment). reQTLs were more likely to overlap transcription factor binding sites, and we uncovered reQTLs for drug metabolizing genes such as CYP3A5. Our results provide insights into the genetic regulation of gene expression in hepatocytes through drug perturbation and provide insight into SNPs that effect the liver's ability to respond to transcription upregulation.


Assuntos
Negro ou Afro-Americano , Locos de Características Quantitativas , Humanos , Locos de Características Quantitativas/genética , Negro ou Afro-Americano/genética , Regulação da Expressão Gênica , Fígado , Expressão Gênica , Polimorfismo de Nucleotídeo Único/genética , Estudo de Associação Genômica Ampla
2.
PLoS Genet ; 16(4): e1008662, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32310939

RESUMO

African Americans (AAs) are disproportionately affected by metabolic diseases and adverse drug events, with limited publicly available genomic and transcriptomic data to advance the knowledge of the molecular underpinnings or genetic associations to these diseases or drug response phenotypes. To fill this gap, we obtained 60 primary hepatocyte cultures from AA liver donors for genome-wide mapping of expression quantitative trait loci (eQTL) using LAMatrix. We identified 277 eGenes and 19,770 eQTLs, of which 67 eGenes and 7,415 eQTLs are not observed in the Genotype-Tissue Expression Project (GTEx) liver eQTL analysis. Of the eGenes found in GTEx only 25 share the same lead eQTL. These AA-specific eQTLs are less correlated to GTEx eQTLs. in effect sizes and have larger Fst values compared to eQTLs found in both cohorts (overlapping eQTLs). We assessed the overlap between GWAS variants and their tagging variants with AA hepatocyte eQTLs and demonstrated that AA hepatocyte eQTLs can decrease the number of potential causal variants at GWAS loci. Additionally, we identified 75,002 exon QTLs of which 48.8% are not eQTLs in AA hepatocytes. Our analysis provides the first comprehensive characterization of AA hepatocyte eQTLs and highlights the unique discoveries that are made possible due to the increased genetic diversity within the African ancestry genome.


Assuntos
Negro ou Afro-Americano/genética , Expressão Gênica/genética , Hepatócitos/metabolismo , Locos de Características Quantitativas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Processamento Alternativo/genética , Citocromo P-450 CYP3A/genética , Éxons/genética , Feminino , Predisposição Genética para Doença , Genética Médica , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Fígado/citologia , Masculino , Proteínas do Tecido Nervoso/genética , Medicina de Precisão
3.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37633519

RESUMO

BACKGROUND AND AIMS: Spontaneous ruptured hepatocellular carcinoma is an uncommon complication, and there are scarce data about non-cirrhotic patients. Tumor treatment is not standardized and the risk of peritoneal dissemination is unclear. AIM: we analyzed the treatment and survival in patients with rHCC on non-cirrhotic liver. METHODS: One hundred and forty-one non-cirrhotic patients with hepatocellular carcinoma diagnosed by histology were included in a multicenter prospective registry (2018-2022). Seven of them (5%) presented with hemoperitoneum due to spontaneous rupture. RESULTS: Liver disease was associated in three patients (42.9%). A single nodule was detected in three cases (42.9%). One patient had vascular invasion and none extrahepatic spread. Initial hemostatic therapy and sequential treatment was individualized. Patients with single nodule were treated: resection (one case) with recurrence at 4 months treated with TACE and sorafenib. TACE/TAE followed by surgery (two cases) one in remission 43 months later, the other had liver recurrence at 18 months and was transplanted. Patients with multiple lesions were treated: TAE/emergency surgery and subsequent systemic therapy (two cases), one received lenvatinib (1-year survival) and the other sorafenib (5-month survival). TAE and surgery with subsequent systemic therapy (one case). Initial hemostatic surgery, dying on admission (one case). No patient developed intraperitoneal metastasis. All patients with multiple lesions died by tumor. The 3-year survival rate was 42.9%. CONCLUSIONS: Initial hemostasis was achieved in all patients by TAE/TACE or surgery. Subsequent treatment was individualized, based on tumor characteristics, regardless of rupture. Long-time remission could be achieved in single nodule patients.

4.
Pharmacogenet Genomics ; 32(1): 1-9, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34380996

RESUMO

OBJECTIVES: Primary nonresponse (PNR) to antitumor necrosis factor-α (TNFα) biologics is a serious concern in patients with inflammatory bowel disease (IBD). We aimed to identify the genetic variants associated with PNR. PATIENTS AND METHODS: Patients were recruited from outpatient GI clinics and PNR was determined using both clinical and endoscopic findings. A case-control genome-wide association study was performed in 589 IBD patients and associations were replicated in an independent cohort of 293 patients. Effect of the associated variant on gene expression and TNFα secretion was assessed by cell-based assays. Pleiotropic effects were investigated by Phenome-wide association study (PheWAS). RESULTS: We identified rs34767465 as associated with PNR to anti-TNFα therapy (odds ratio: 2.07, 95% CI, 1.46-2.94, P = 2.43 × 10-7, [replication odds ratio: 1.8, 95% CI, 1.04-3.16, P = 0.03]). rs34767465 is a multiple-tissue expression quantitative trait loci for FAM114A2. Using RNA-sequencing and protein quantification from HapMap lymphoblastoid cell lines (LCLs), we found a significant decrease in FAM114A2 mRNA and protein expression in both heterozygous and homozygous genotypes when compared to wild type LCLs. TNFα secretion was significantly higher in THP-1 cells [differentiated into macrophages] with FAM114A2 knockdown versus controls. Immunoblotting experiments showed that depletion of FAM114A2 impaired autophagy-related pathway genes suggesting autophagy-mediated TNFα secretion as a potential mechanism. PheWAS showed rs34767465 was associated with comorbid conditions found in IBD patients (derangement of joints [P = 3.7 × 10-4], pigmentary iris degeneration [P = 5.9 × 10-4], diverticulum of esophagus [P = 7 × 10-4]). CONCLUSIONS: We identified a variant rs34767465 associated with PNR to anti-TNFα biologics, which increases TNFα secretion through mechanism related to autophagy. rs34767465 may also explain the comorbidities associated with IBD.


Assuntos
Estudo de Associação Genômica Ampla , Doenças Inflamatórias Intestinais , Estudos de Casos e Controles , Estudos de Coortes , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Fator de Necrose Tumoral alfa/genética
5.
Mol Cell Proteomics ; 19(6): 971-993, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32265294

RESUMO

The onset of obesity-linked type 2 diabetes (T2D) is marked by an eventual failure in pancreatic ß-cell function and mass that is no longer able to compensate for the inherent insulin resistance and increased metabolic load intrinsic to obesity. However, in a commonly used model of T2D, the db/db mouse, ß-cells have an inbuilt adaptive flexibility enabling them to effectively adjust insulin production rates relative to the metabolic demand. Pancreatic ß-cells from these animals have markedly reduced intracellular insulin stores, yet high rates of (pro)insulin secretion, together with a substantial increase in proinsulin biosynthesis highlighted by expanded rough endoplasmic reticulum and Golgi apparatus. However, when the metabolic overload and/or hyperglycemia is normalized, ß-cells from db/db mice quickly restore their insulin stores and normalize secretory function. This demonstrates the ß-cell's adaptive flexibility and indicates that therapeutic approaches applied to encourage ß-cell rest are capable of restoring endogenous ß-cell function. However, mechanisms that regulate ß-cell adaptive flexibility are essentially unknown. To gain deeper mechanistic insight into the molecular events underlying ß-cell adaptive flexibility in db/db ß-cells, we conducted a combined proteomic and post-translational modification specific proteomic (PTMomics) approach on islets from db/db mice and wild-type controls (WT) with or without prior exposure to normal glucose levels. We identified differential modifications of proteins involved in redox homeostasis, protein refolding, K48-linked deubiquitination, mRNA/protein export, focal adhesion, ERK1/2 signaling, and renin-angiotensin-aldosterone signaling, as well as sialyltransferase activity, associated with ß-cell adaptive flexibility. These proteins are all related to proinsulin biosynthesis and processing, maturation of insulin secretory granules, and vesicular trafficking-core pathways involved in the adaptation of insulin production to meet metabolic demand. Collectively, this study outlines a novel and comprehensive global PTMome signaling map that highlights important molecular mechanisms related to the adaptive flexibility of ß-cell function, providing improved insight into disease pathogenesis of T2D.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Hiperglicemia/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Obesidade/metabolismo , Proinsulina/biossíntese , Proteoma/metabolismo , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Modelos Animais de Doenças , Adesões Focais , Ontologia Genética , Glucose/metabolismo , Hiperglicemia/genética , Secreção de Insulina , Células Secretoras de Insulina/patologia , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proinsulina/metabolismo , Mapas de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Proteoma/genética , Proteômica , Sistema Renina-Angiotensina , Ácidos Siálicos/metabolismo , Espectrometria de Massas em Tandem , Ubiquitinação
6.
J Proteome Res ; 18(9): 3245-3258, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31317746

RESUMO

For the treatment of patients with prediabetes or diabetes, clinical evidence has emerged that ß-cell function can be restored by glucose-lowering therapeutic strategies. However, little is known about the molecular mechanisms underlying this functional adaptive behavior of the pancreatic ß-cell. This study examines the dynamic changes in protein expression and phosphorylation state associated with (pro)insulin production and secretory pathway function mediated by euglycemia to induce ß-cell rest in obese/diabetic db/db islet ß-cells. Unbiased quantitative profiling of the protein expression and phosphorylation events that occur upon ß-cell adaption during the transition from hyperglycemia to euglycemia was assessed in isolated pancreatic islets from obese diabetic db/db and wild-type (WT) mice using quantitative proteomics and phosphoproteomics together with bioinformatics analysis. Dynamic changes in the expression and phosphorylation of proteins associated with pancreatic ß-cell (pro)insulin production and complementary regulated-secretory pathway regulation were observed in obese diabetic db/db islets in a hyperglycemic environment, relative to WT mouse islets in a normal euglycemic environment, that resolved when isolated db/db islets were exposed to euglycemia for 12 h in vitro. By similarly treating WT islets in parallel, the effects of tissue culture could be mostly eliminated and only those changes associated with resolution by euglycemia were assessed. Among such regulated protein phosphorylation-dependent signaling events were those associated with COPII-coated vesicle-dependent ER exit, ER-to-Golgi trafficking, clathrin-coat disassembly, and a particular association for the luminal Golgi protein kinase, FAM20C, in control of distal secretory pathway trafficking, sorting, and granule biogenesis. Protein expression and especially phosphorylation play key roles in the regulation of (pro)insulin production, correlative secretory pathway trafficking, and the restoration of ß-cell secretory capacity in the adaptive functional ß-cell response to metabolic demand, especially that mediated by glucose.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Proteínas da Matriz Extracelular/genética , Estado Pré-Diabético/tratamento farmacológico , Proteômica , Animais , Glicemia/efeitos dos fármacos , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/genética , Diabetes Mellitus Tipo 2/sangue , Modelos Animais de Doenças , Glucose/metabolismo , Complexo de Golgi/efeitos dos fármacos , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/genética , Insulina/biossíntese , Insulina/genética , Células Secretoras de Insulina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Obesidade/tratamento farmacológico , Obesidade/genética , Estado Pré-Diabético/sangue , Transporte Proteico/efeitos dos fármacos
7.
JAMA ; 320(16): 1670-1677, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30357299

RESUMO

Importance: Major warfarin-related bleeding occurs more frequently in African Americans than in other populations. Identification of potential genetic factors related to this adverse event may help identify at-risk patients. Objective: To identify genetic factors associated with warfarin-related bleeding in patients of African descent at an international normalized ratio (INR) of less than 4. Design, Setting, and Participants: A case-control genome-wide association study involving patients of African descent taking warfarin was conducted in a discovery cohort (University of Chicago [2009-2011] and the University of Illinois at Chicago [2002-2011]), and associations were confirmed in a replication cohort (University of Chicago [2015-2016]). Potential population stratification was examined in the discovery cohort by principal component analysis. Odds ratios (ORs) and 95% CIs were computed for bleeding risk by logistic regression analysis. Summary statistics from the discovery and the replication cohorts were analyzed with a fixed effects meta-analysis. The potential influence of single-nucleotide polymorphisms (SNPs) on gene expression was studied by luciferase expression assays. Exposures: Single-nucleotide polymorphisms associated with warfarin-related bleeding. Main Outcomes and Measures: Major bleeding-defined as bleeding requiring hospitalization, causing a decrease in hemoglobin level of more than 2 g/dL, requiring blood transfusion, or any combination of the 3-while taking warfarin at an INR of less than 4. Results: The discovery cohort consisted of 31 cases (mean age, 60.1 years [SD, 14.9 years], 26 women [83.9%]) and 184 warfarin-treated controls (mean age, 57.1 years [SD, 15.7 years]) with no documented bleeding. The replication cohort consisted of 40 cases (mean age, 55.6 years [SD, 17.3 years], 27 women [67.5%]), and 148 warfarin-treated controls (mean age, 55.4 years [SD, 17.1 years]; 98 women [66.2%]) with no documented bleeding. In the discovery cohort, 4 SNPs in linkage disequilibrium on chromosome 6 (rs115112393, rs16871327, rs78132896, and rs114504854) were associated with warfarin-related bleeding but did not reach genome-wide significance. The SNP rs78132896 occurred in 11 cases (35.5%) and 9 controls (4.9%) in the discovery cohort (OR, 8.31; 95% CI, 3.2-21.5; P < 6.21 × 10-8), and the association was confirmed in the replication cohort (the SNP was present in 14 cases [35.0%] and 7 controls [4.8%]; OR, 8.24; 95% CI, 3.1-25.3, P = 5.64 × 10-5). Genome-wide significance of this SNP was achieved when the cohorts were combined via meta-analysis (OR, 8.27; 95% CI, 4.18-16.38; P = 2.05 × 10-11). These SNPs are found only in people of African descent. In vitro luciferase expression assays demonstrated that rs16871327 (enhancer SNP) and rs78132896 (promoter SNP) risk alleles together increased EPHA7 gene (Entrez Gene 2045) transcription by a mean of 14.95 (SD, 1.7) compared with wild-type alleles (mean, 9.56 [SD, 0.84]; difference, 5.39; 95% CI, 4.1-6.6; P < .001). Conclusions and Relevance: In this preliminary study involving patients of African descent taking warfarin, 4 single-nucleotide polymorphisms in linkage disequilibrium on chromosome 6 were associated with an increased risk of major bleeding at INR of less than 4. Validation of these findings in an independent prospective cohort is required.


Assuntos
Anticoagulantes/efeitos adversos , Negro ou Afro-Americano/genética , Cromossomos Humanos Par 6 , Hemorragia/genética , Polimorfismo de Nucleotídeo Único , Varfarina/efeitos adversos , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Razão de Chances
8.
Pac Symp Biocomput ; 29: 341-358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38160291

RESUMO

Gene imputation and TWAS have become a staple in the genomics medicine discovery space; helping to identify genes whose regulation effects may contribute to disease susceptibility. However, the cohorts on which these methods are built are overwhelmingly of European Ancestry. This means that the unique regulatory variation that exist in non-European populations, specifically African Ancestry populations, may not be included in the current models. Moreover, African Americans are an admixed population, with a mix of European and African segments within their genome. No gene imputation model thus far has incorporated the effect of local ancestry (LA) on gene expression imputation. As such, we created LA-GEM which was trained and tested on a cohort of 60 African American hepatocyte primary cultures. Uniquely, LA-GEM include local ancestry inference in its prediction of gene expression. We compared the performance of LA-GEM to PrediXcan trained the same dataset (with no inclusion of local ancestry) We were able to reliably predict the expression of 2559 genes (1326 in LA-GEM and 1236 in PrediXcan). Of these, 546 genes were unique to LA-GEM, including the CYP3A5 gene which is critical to drug metabolism. We conducted TWAS analysis on two African American clinical cohorts with pharmacogenomics phenotypic information to identity novel gene associations. In our IWPC warfarin cohort, we identified 17 transcriptome-wide significant hits. No gene reached are prespecified significance level in the clopidogrel cohort. We did see suggestive association with RAS3A to P2RY12 Reactivity Units (PRU), a clinical measure of response to anti-platelet therapy. This method demonstrated the need for the incorporation of LA into study in admixed populations.


Assuntos
Biologia Computacional , Estudo de Associação Genômica Ampla , Humanos , Estudo de Associação Genômica Ampla/métodos , Biologia Computacional/métodos , Varfarina , Transcriptoma , Polimorfismo de Nucleotídeo Único
9.
Children (Basel) ; 11(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38790532

RESUMO

Cancer poses significant emotional challenges for children and adolescents, despite improvements in survival rates due to new therapies. However, there is growing concern about the long-term effects, including fertility issues. This review examines recent advancements and future directions in fertility preservation within a pediatric population subjected to oncological therapies. Worldwide, there is variability in the availability of fertility preservation methods, influenced by factors like development status and governmental support. The decision to pursue preservation depends on the risk of gonadotoxicity, alongside factors such as diagnosis, treatment, clinical status, and prognosis. Currently, options for preserving fertility in prepubertal boys are limited compared to girls, who increasingly have access to ovarian tissue preservation. Adolescents and adults have more options available, but ethical considerations remain complex and diverse.

10.
Biol Reprod ; 89(3): 50, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23884645

RESUMO

For the past three decades, assisted reproductive technologies (ART) have revolutionized infertility treatments. The use of ART is thought to be safe. However, early investigations suggested that children born as a result of ART had higher risk of diseases with epigenetic etiologies, including imprinting disorders caused by a lack of maternal methylation at imprinting control elements. In addition, large epidemiology studies have highlighted an increased risk of obstetric complications, including severe intrauterine growth restriction (IUGR) in babies conceived using ART. It is plausible that the increased frequency of IUGR may be due to abnormal imprinting because these transcripts are key for normal fetal growth and development. To address this, we have collected a large cohort of placenta and cord blood samples from ART conceptions and compared the imprinting status with appropriate non-ART population. Using a custom DNA methylation array that simultaneously quantifies 25 imprinted differentially methylated regions, we observed similar epigenetic profiles between groups. A multiplex Sequenom iPLEX allelic expression assay revealed monoallelic expression for 11 imprinted transcripts in our placenta cohort. We also observe appropriate gestational age-dependent methylation dynamics at retrotransposable elements and promoters associated with growth genes in ART placental biopsies. This study confirms that children conceived by ART do not show variability in imprinted regulation and that loss-of-imprinting is not commonly associated with nonsyndromic IUGR or prematurity.


Assuntos
Metilação de DNA , Impressão Genômica , Instabilidade Genômica , Idade Gestacional , Complicações na Gravidez/genética , Técnicas de Reprodução Assistida/efeitos adversos , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Infertilidade/epidemiologia , Infertilidade/genética , Infertilidade/terapia , Masculino , Placenta/metabolismo , Placenta/patologia , Gravidez , Complicações na Gravidez/epidemiologia , Gravidez Múltipla/genética , Gravidez Múltipla/metabolismo , Técnicas de Reprodução Assistida/estatística & dados numéricos
11.
Clin Pharmacol Ther ; 113(3): 624-633, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36507737

RESUMO

The anticoagulant warfarin is commonly used to control and prevent thrombotic disorders, such as venous thromboembolism (VTE), which disproportionately afflicts African Americans. Despite the importance of copy number variants (CNVs), few studies have focused on characterizing and understanding their role in drug response and disease risk among African Americans. In this study, we conduct the first genome-wide analysis of CNVs to more comprehensively account for the contribution of genetic variation in warfarin dose requirement and VTE risk among African Americans. We used hidden Markov models to detect CNVs from high-throughput single-nucleotide polymorphism arrays for 340 African American participants in the International Warfarin Pharmacogenetics Consortium. We identified 11,570 CNVs resulting in 2,038 copy number variable regions (CNVRs) and found 3 CNVRs associated with warfarin dose requirement and 3 CNVRs associated with VTE risk in African Americans. CNVRs 1q31.2del and 6q14.1del were associated with increased warfarin dose requirement (ß = 11.18 and 4.94, respectively; Pemp  = < 0.002); CNVR 19p13.31del was associated with decreased warfarin dose requirement (ß = -1.41, Pemp  = 0.0004); CNVRs (2p22.1del and 5q35.1-q35.2del) were found to be associated with increased risk of VTE (odds ratios (ORs) = 1.88 and 14.9, respectively; Pemp ≤0.02); and CNVR 10q26.12del was associated with a decreased risk of VTE (OR = 0.6; Pemp  = 0.05). Modeling of the 10q26.12del in HepG2 cells revealed that this deletion results in decreased fibrinogen gene expression, decreased fibrinogen and WDR11 protein levels, and decreased secretion of fibrinogen into the extracellular matrix. We found robust evidence that CNVRs could contribute to warfarin dose requirement and risk of VTE in African Americans and for 10q26.3del describe a possible pathogenic mechanism.


Assuntos
Tromboembolia Venosa , Varfarina , Humanos , Varfarina/efeitos adversos , Negro ou Afro-Americano/genética , Tromboembolia Venosa/genética , Variações do Número de Cópias de DNA , Anticoagulantes/efeitos adversos , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
12.
Pac Symp Biocomput ; 28: 221-232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36540979

RESUMO

Pharmacogenomics has long lacked dedicated studies in African Americans, resulting in a lack of indepth data in this populations. The ACCOuNT consortium has collected a cohort of 167 African American patients on steady state clopidogrel with the goal of discovering population specific variation that may contribute to the response of this anti-platelet agent. Here we analyze the role of both global and local ancestry on the clinical phenotypes of P2Y12 reaction units (PRU) and high on-treatment platelet reactivity (HTPR) in this cohort. We found that local ancestry at the TSS of three genes, IRS-1, ABCB1 and KDR were nominally associated with PRU, and local ancestry-adjusted SNP association identified variants in ITGA2 associated to increased PRU. These finding help to explain the variability in drug response seen in African Americans, especially as few studies on genes outside of CYP2C19 has been conducted in this population.


Assuntos
Inibidores da Agregação Plaquetária , Ticlopidina , Humanos , Clopidogrel/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/uso terapêutico , Negro ou Afro-Americano/genética , Biologia Computacional , Citocromo P-450 CYP2C19/genética
13.
medRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106031

RESUMO

Clopidogrel, an anti-platelet drug, used to prevent thrombosis after percutaneous coronary intervention. Clopidogrel resistance results in recurring ischemic episodes, with African Americans suffering disproportionately. The aim of this study was to identify biomarkers of clopidogrel resistance in African American patients. We conducted a genome-wide association study, including local ancestry adjustment, in 141 African Americans on clopidogrel to identify associations with high on-treatment platelet reactivity (HTPR). We validated genome-wide and suggestive hits in an independent cohort of African American clopidogrel patients (N = 823) from the Million Veteran's Program (MVP) along with in vitro functional follow up. We performed differential gene expression (DGE) analysis in whole blood with functional follow-up in MEG-01 cells. We identified rs7807369, within thrombospondin 7A (THSD7A), as significantly associated with increasing risk of HTPR (p = 4.56 × 10-9). Higher THSD7A expression was associated with HTPR in an independent gene expression cohort of clopidogrel treated patients (p = 0.004) and supported by increased gene expression on THSD7A in primary human endothelial cells carrying the risk haplotype. Two SNPs (rs1149515 and rs191786) were validated in the MVP cohort. DGE analysis identified an association with decreased LAIR1 expression to HTPR. LAIR1 knockdown in a MEG-01 cells resulted in increased expression of SYK and AKT1, suggesting an inhibitory role of LAIR1 in the Glycoprotein VI pathway. Notably, the CYP2C19 variants showed no association with clopidogrel response in the discovery or MVP cohorts. In summary, these finding suggest that other variants outside of CYP2C19 star alleles play an important role in clopidogrel response in African Americans.

14.
medRxiv ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37873439

RESUMO

Background: High on-treatment platelet reactivity (HTPR) with clopidogrel is predictive of ischemic events in adults with coronary artery disease. Despite strong data suggesting HTPR varies with ethnicity, including clinical and genetic variables, no genome-wide association study (GWAS) of clopidogrel response has been performed among Caribbean Hispanics. This study aimed to identify genetic predictors of HTPR in a cohort of Caribbean Hispanic cardiovascular patients from Puerto Rico. Methods: Local Ancestry inference (LAI) and traditional GWASs were performed on a cohort of 511 clopidogrel-treated patients, stratified based on their P2Y12 reaction units (PRU) into responders and non-responders (HTPR). Results: The LAI GWAS identified variants within the CYP2C19 region associated with HTPR, predominantly driven by individuals of European ancestry and absent in those with native ancestry. Incorporating local ancestry adjustment notably enhanced our ability to detect associations. While no loci reached traditional GWAS significance, three variants showed suggestive significance at chromosomes 3, 14 and 22 (OSBPL10 rs1376606, DERL3 rs5030613, and RGS6 rs9323567). In addition, a variant in the UNC5C gene on chromosome 4 was associated with an increased risk of HTPR. These findings were not identified in other cohorts, highlighting the unique genetic landscape of Caribbean Hispanics. Conclusion: This is the first GWAS of clopidogrel response in Hispanics, confirming the relevance of the CYP2C19 cluster, particularly among those with European ancestry, and also identifying novel markers in a diverse patient population. Further studies are warranted to replicate our findings in other diverse cohorts and meta-analyses.

15.
Cell Metab ; 5(3): 221-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17339029

RESUMO

Insulin production in pancreatic beta cells is predominantly regulated through glucose control of proinsulin translation. Previously, this was shown to require sequences within the untranslated regions (UTRs) of the preproinsulin (ppI) mRNA. Here, those sequences were found to be sufficient for specific glucose-regulated proinsulin translation. Furthermore, an element 40-48 bp from the 5' end of the ppI mRNA specifically bound a factor present in islets of Langerhans. Glucose-responsive factor binding to this cis-element exhibited temporal and glucose-concentration-dependent patterns that paralleled proinsulin biosynthesis. Mutating this cis-element abolished the ability of ppI mRNA UTRs to confer glucose regulation upon translation. Like the rat 5'UTR, the human ppI 5'UTR conferred glucose regulation of translation. However alternative splicing of the human 5'UTR that disrupts the cis-element abolished glucose-regulated translation. These data indicate that glucose regulation of cis-element/trans-acting factor interaction is a key component of the mechanism by which glucose regulates insulin production.


Assuntos
Regiões 5' não Traduzidas , Glucose/metabolismo , Proinsulina/biossíntese , Proinsulina/genética , Biossíntese de Proteínas , Precursores de Proteínas/biossíntese , Precursores de Proteínas/genética , Processamento Alternativo , Animais , Regulação da Expressão Gênica , Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Transcrição Gênica
16.
Pac Symp Biocomput ; 26: 244-255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33691021

RESUMO

Epigenetics is a reversible molecular mechanism that plays a critical role in many developmental, adaptive, and disease processes. DNA methylation has been shown to regulate gene expression and the advent of high throughput technologies has made genome-wide DNA methylation analysis possible. We investigated the effect of DNA methylation on eQTL mapping (methylation-adjusted eQTLs), by incorporating DNA methylation as a SNP-based covariate in eQTL mapping in African American derived hepatocytes. We found that the addition of DNA methylation uncovered new eQTLs and eGenes. Previously discovered eQTLs were significantly altered by the addition of DNA methylation data suggesting that methylation may modulate the association of SNPs to gene expression. We found that methylation-adjusted eQTLs that were less significant compared to PC-adjusted eQTLs were enriched in lipoprotein measurements (FDR=0.0040), immune system disorders (FDR = 0.0042), and liver enzyme measurements (FDR=0.047), suggesting that DNA methylation modulates the genetic regulation of these phenotypes. Our methylation-adjusted eQTL analysis also uncovered novel SNP-gene pairs. For example, we found that the SNP, rs1332018, was associated to GSTM3. GSTM3 expression has been linked to Hepatitis B which African Americans suffer from disproportionately. Our methylation-adjusted method adds new understanding to the genetic basis of complex diseases that disproportionally affect African Americans.


Assuntos
Negro ou Afro-Americano , Metilação de DNA , Negro ou Afro-Americano/genética , Biologia Computacional , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
17.
Clin Pharmacol Ther ; 110(3): 702-713, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34255863

RESUMO

The African American (AA) population displays a 1.6 to 3-fold higher incidence of thrombosis and stroke mortality compared with European Americans (EAs). Current antiplatelet therapies target the ADP-mediated signaling pathway, which displays significant pharmacogenetic variation for platelet reactivity. The focus of this study was to define underlying population differences in platelet function in an effort to identify novel molecular targets for future antiplatelet therapy. We performed deep coverage RNA-Seq to compare gene expression levels in platelets derived from a cohort of healthy volunteers defined by ancestry determination. We identified > 13,000 expressed platelet genes of which 480 were significantly differentially expressed genes (DEGs) between AAs and EAs. DEGs encoding proteins known or predicted to modulate platelet aggregation, morphology, or platelet count were upregulated in AA platelets. Numerous G-protein coupled receptors, ion channels, and pro-inflammatory cytokines not previously associated with platelet function were likewise differentially expressed. Many of the signaling proteins represent potential pharmacologic targets of intervention. Notably, we confirmed the differential expression of cytokines IL32 and PROK2 in an independent cohort by quantitative real-time polymerase chain reaction, and provide functional validation of the opposing actions of these two cytokines on collagen-induced AA platelet aggregation. Using Genotype-Tissue Expression whole blood data, we identified 516 expression quantitative trait locuses with Fst values > 0.25, suggesting that population-differentiated alleles may contribute to differences in gene expression. This study identifies gene expression differences at the population level that may affect platelet function and serve as potential biomarkers to identify cardiovascular disease risk. Additionally, our analysis uncovers candidate novel druggable targets for future antiplatelet therapies.


Assuntos
Plaquetas/fisiologia , RNA Mensageiro/genética , Grupos Raciais/genética , Adolescente , Negro ou Afro-Americano/genética , Biomarcadores/sangue , Plaquetas/efeitos dos fármacos , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Citocinas/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Masculino , Inibidores da Agregação Plaquetária/uso terapêutico , Testes de Função Plaquetária/métodos
18.
Ann Pharmacother ; 43(4): 748-53, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19299535

RESUMO

The new vision for Canadian pharmacy practice, as outlined in the Blueprint for Pharmacy, drives for a more patient-centered and outcomes-focused approach to patient care than ever before. As of 2007 and 2009, pharmacists in Alberta and British Columbia, respectively, have the ability to adapt and renew existing prescriptions without prior approval from the physician. This necessarily puts a greater emphasis on the practice of pharmaceutical care, entailing the formation of a closer professional, more personalized bonding between pharmacist and patient. No one, however, seems to be paying much attention to the greater moral and ethical responsibility of pharmacists as they take on expanded roles. Not only are the greater expectations not coupled with greater respect for the pharmacist's freedom of conscience, but provincial jurisdictions across the country vary in degrees of tolerance toward pharmacists whose views differ from those held by the licensing authorities.


Assuntos
Consciência , Farmácia/métodos , Farmácia/tendências , Padrões de Prática Médica/normas , Padrões de Prática Médica/tendências , Alberta , Colúmbia Britânica , Códigos de Ética/tendências , Humanos , Princípios Morais , Guias de Prática Clínica como Assunto/normas , Prescrições/normas , Resultado do Tratamento
19.
Mol Endocrinol ; 21(9): 2255-69, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17579214

RESUMO

Endocrine cells are continually regulating the balance between hormone biosynthesis, secretion, and intracellular degradation to ensure that cellular hormone stores are maintained at optimal levels. In pancreatic beta-cells, intracellular insulin stores in beta-granules are mostly upheld by efficiently up-regulating proinsulin biosynthesis at the translational level to rapidly replenish the insulin lost via exocytosis. Under normal circumstances, intracellular degradation of insulin plays a relatively minor janitorial role in retiring aged beta-granules, apparently via crinophagy. However, this mechanism alone is not sufficient to maintain optimal insulin storage in beta-cells when insulin secretion is dysfunctional. Here, we show that despite an abnormal imbalance of glucose/glucagon-like peptide 1 regulated insulin production over secretion in Rab3A(-/-) mice compared with control animals, insulin storage levels were maintained due to increased intracellular beta-granule degradation. Electron microscopy analysis indicated that this was mediated by a significant 12-fold up-regulation of multigranular degradation vacuoles in Rab3A(-/-) mouse islet beta-cells (P

Assuntos
Autofagia/fisiologia , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Animais , Secreção de Insulina , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proinsulina/biossíntese , Proteína rab3A de Ligação ao GTP/deficiência , Proteína rab3A de Ligação ao GTP/genética
20.
Artigo em Espanhol | LILACS | ID: biblio-1556402

RESUMO

Se plantea el problema educativo en el marco del currículo de la educación superior, cuestionando la relación que existe entre la descripción de los elementos curriculares, con la conceptuación propuestas en las teorías educativas. Objetivo: analizar el diseño curricular de la especialidad de Medicina Física y Rehabilitación para mejorar el modelo curricular como base para la creación de la Subespecialidad en Medicina de Rehabilitación Pediátrica. Método: el presente estudio desarrolla un enfoque cualicuantitativo de tipo observacional, descriptivo, transversal y documental. Busca analizar los elementos curriculares del Programa Académico de la Especialidad en Medicina Física y Rehabilitación y su fundamentación filosófica. Se realizó entrevistas estructuradas a 11 docentes instructores, 3 docentes responsables, 20 especialistas egresados y 4 expertos de la especialidad reconocidos en Bolivia. Análisis y revisión de la literatura, como de diferentes programas de la especialidad. De tipo propositivo porque plantea el rediseño curricular de la especialidad mediante un análisis socio-educativo y filosofía transcompleja. Resultados: los elementos curriculares de la especialidad de Medicina Física y Rehabilitación se encuentran fragmentados. La metodología curricular no muestra una relación clara entre la fundamentación, perfil profesional, organización y evaluación. Existe la necesidad de apertura de nuevos posgrados. Conclusiones: En base a los resultados obtenidos en la investigación se plantea un rediseño curricular bajo el paradigma educativo transcomplejo que propone las bases teóricas para la reforma del desarrollo curricular de la especialidad en estudio


The educational problem is raised within the framework of the higher education curriculum, questioning the relationship that exists between the description of the curricular elements with the conceptualization proposed in educational theories. Objective: to analyze the curricular design of the specialty of Physical Medicine and Rehabilitation to improve the curricular model as a basis for the creation of the Subspecialty in Pediatric Rehabilitation Medicine. Method: the present study develops a qualitative-quantitative approach of an observational, descriptive, cross-sectional and documentary type. It seeks to analyze the curricular elements of the Academic Program of the Specialty in Physical Medicine and Rehabilitation and its philosophical foundation. Structured interviews were conducted with 11 instructor teachers, 3 responsible teachers, 20 graduate specialists and 4 experts in the specialty recognized in Bolivia. Analysis and review of the literature, as well as of different specialty programs. Propositive because it proposes the curricular redesign of the specialty through a socioeducational analysis and transcomplex philosophy. Results: the curricular elements of the specialty of Physical Medicine and Rehabilitation are fragmented. The curricular methodology does not show a clear relationship between the foundation, professional profile, organization and evaluation. There is a need to open new postgraduate courses. Conclusions: Based on the results obtained in the research, a curricular redesign is proposed under the transcomplex educational paradigm that proposes the theoretical bases for the reform of the curricular development of the specialty under study

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