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PURPOSE: Up to 30% of patients with Brugada syndrome (BrS) carry loss-of-function (LoF) variants in the cardiac sodium channel gene SCN5A encoding for the protein NaV1.5. Recent studies suggested that NaV1.5 can dimerize, and some variants exert dominant negative effects. In this study, we sought to explore the generality of missense variant NaV1.5 dominant negative effects and their clinical severity. METHODS: We identified 35 LoF variants (<10% of wild type [WT] peak current) and 15 partial LoF variants (10%-50% of WT peak current) that we assessed for dominant negative effects. SCN5A variants were studied in HEK293T cells, alone or in heterozygous coexpression with WT SCN5A using automated patch clamp. To assess the clinical risk, we compared the prevalence of dominant negative vs putative haploinsufficient (frameshift, splice, or nonsense) variants in a BrS consortium and the Genome Aggregation Database population database. RESULTS: In heterozygous expression with WT, 32 of 35 LoF and 6 of 15 partial LoF variants showed reduction to <75% of WT-alone peak current, showing a dominant negative effect. Individuals with dominant negative LoF variants had an elevated disease burden compared with the individuals with putative haploinsufficient variants (2.7-fold enrichment in BrS cases, P = .019). CONCLUSION: Most SCN5A missense LoF variants exert a dominant negative effect. This class of variant confers an especially high burden of BrS.
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Síndrome de Brugada , Canal de Sódio Disparado por Voltagem NAV1.5 , Síndrome de Brugada/genética , Células HEK293 , Humanos , Mutação de Sentido Incorreto/genética , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismoRESUMO
RATIONALE: Asymptomatic relatives of patients with familial interstitial pneumonia (FIP), the inherited form of idiopathic interstitial pneumonia, carry increased risk for developing interstitial lung disease. OBJECTIVES: Studying these at-risk individuals provides a unique opportunity to investigate early stages of FIP pathogenesis and develop predictive models of disease onset. METHODS: Seventy-five asymptomatic first-degree relatives of FIP patients (mean age, 50.8 yr) underwent blood sampling and high-resolution chest computed tomography (HRCT) scanning in an ongoing cohort study; 72 consented to bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsies. Twenty-seven healthy individuals were used as control subjects. MEASUREMENTS AND MAIN RESULTS: Eleven of 75 at-risk subjects (14%) had evidence of interstitial changes by HRCT, whereas 35.2% had abnormalities on transbronchial biopsies. No differences were noted in inflammatory cells in BAL between at-risk individuals and control subjects. At-risk subjects had increased herpesvirus DNA in cell-free BAL and evidence of herpesvirus antigen expression in alveolar epithelial cells (AECs), which correlated with expression of endoplasmic reticulum stress markers in AECs. Peripheral blood mononuclear cell and AEC telomere length were shorter in at-risk individuals than healthy control subjects. The minor allele frequency of the Muc5B rs35705950 promoter polymorphism was increased in at-risk subjects. Levels of several plasma biomarkers differed between at-risk subjects and control subjects, and correlated with abnormal HRCT scans. CONCLUSIONS: Evidence of lung parenchymal remodeling and epithelial dysfunction was identified in asymptomatic individuals at risk for FIP. Together, these findings offer new insights into the early pathogenesis of idiopathic interstitial pneumonia and provide an ongoing opportunity to characterize presymptomatic abnormalities that predict progression to clinical disease.
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Doenças Pulmonares Intersticiais/diagnóstico , Fenótipo , Adulto , Idoso , Doenças Assintomáticas , Biomarcadores/metabolismo , Biópsia , Lavagem Broncoalveolar , Broncoscopia , Estudos de Casos e Controles , DNA Viral/análise , Feminino , Frequência do Gene , Marcadores Genéticos , Herpesviridae/genética , Herpesviridae/isolamento & purificação , Humanos , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Doenças Pulmonares Intersticiais/genética , Doenças Pulmonares Intersticiais/metabolismo , Doenças Pulmonares Intersticiais/virologia , Masculino , Pessoa de Meia-Idade , Mucina-5B/genética , Polimorfismo Genético , Estudos Prospectivos , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: Patients with rheumatoid arthritis (RA) have accelerated atherosclerosis, but there is limited information about the genetic contribution to atherosclerosis in this population. Therefore, we examined the association between selected genetic polymorphisms and coronary atherosclerosis in patients with RA. METHODS: Genotypes for single-nucleotide polymorphisms (SNPs) in 152 candidate genes linked with autoimmune or cardiovascular risk were measured in 140 patients with RA. The association between the presence of coronary artery calcium (CAC) and SNP allele frequency was assessed by logistic regression with adjustment for age, sex, and race. To adjust for multiple comparisons, a false discovery rate (FDR) threshold was set at 20%. RESULTS: Patients with RA were 54±11 years old and predominantly Caucasian (89%) and female (69%). CAC was present in 70 patients (50%). A variant in rs2073618 that encodes an Asn3Lys missense substitution in the osteoprotegerin gene (OPG, TNFRSF11B) was significantly associated with the presence of CAC (OR=4.09, p<0.00026) and withstands FDR correction. CONCLUSION: Our results suggest that a polymorphism of the TNFRSF11B gene, which encodes osteoprotegerin, is associated with the presence of coronary atherosclerosis in patients with RA. Replication of this finding in independent validation cohorts will be of interest.
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Artrite Reumatoide/complicações , Artrite Reumatoide/genética , Aterosclerose/genética , Doença da Artéria Coronariana/genética , Osteoprotegerina/genética , Adulto , Idoso , Artrite Reumatoide/etnologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , População Branca/genética , População Branca/estatística & dados numéricosAssuntos
Predisposição Genética para Doença/genética , Mucina-5B/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Síndrome do Desconforto Respiratório/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
AIMS: While variants in KCNQ1 are the commonest cause of the congenital long QT syndrome, we and others find only a small IKs in cardiomyocytes from human-induced pluripotent stem cells (iPSC-CMs) or human ventricular myocytes. METHODS AND RESULTS: We studied population control iPSC-CMs and iPSC-CMs from a patient with Jervell and Lange-Nielsen (JLN) syndrome due to compound heterozygous loss-of-function (LOF) KCNQ1 variants. We compared the effects of pharmacologic IKs block to those of genetic KCNQ1 ablation, using JLN cells, cells homozygous for the KCNQ1 LOF allele G643S, or siRNAs reducing KCNQ1 expression. We also studied the effects of two blockers of IKr, the other major cardiac repolarizing current, in the setting of pharmacologic or genetic ablation of KCNQ1: moxifloxacin, associated with a very low risk of drug-induced long QT, and dofetilide, a high-risk drug. In control cells, a small IKs was readily recorded but the pharmacologic IKs block produced no change in action potential duration at 90% repolarization (APD90). In contrast, in cells with genetic ablation of KCNQ1 (JLN), baseline APD90 was markedly prolonged compared with control cells (469 ± 20 vs. 310 ± 16â ms). JLN cells displayed increased sensitivity to acute IKr block: the concentration (µM) of moxifloxacin required to prolong APD90 100 msec was 237.4 [median, interquartile range (IQR) 100.6-391.6, n = 7] in population cells vs. 23.7 (17.3-28.7, n = 11) in JLN cells. In control cells, chronic moxifloxacin exposure (300â µM) mildly prolonged APD90 (10%) and increased IKs, while chronic exposure to dofetilide (5â nM) produced greater prolongation (67%) and no increase in IKs. However, in the siRNA-treated cells, moxifloxacin did not increase IKs and markedly prolonged APD90. CONCLUSION: Our data strongly suggest that KCNQ1 expression modulates baseline cardiac repolarization, and the response to IKr block, through mechanisms beyond simply generating IKs.
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Potenciais de Ação , Células-Tronco Pluripotentes Induzidas , Síndrome de Jervell-Lange Nielsen , Canal de Potássio KCNQ1 , Moxifloxacina , Miócitos Cardíacos , Fenetilaminas , Sulfonamidas , Canal de Potássio KCNQ1/genética , Canal de Potássio KCNQ1/metabolismo , Humanos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Potenciais de Ação/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Moxifloxacina/farmacologia , Fenetilaminas/farmacologia , Sulfonamidas/farmacologia , Síndrome de Jervell-Lange Nielsen/genética , Síndrome de Jervell-Lange Nielsen/metabolismo , Síndrome de Jervell-Lange Nielsen/fisiopatologia , Bloqueadores dos Canais de Potássio/farmacologia , Fluoroquinolonas/farmacologiaRESUMO
BACKGROUND: Brugada syndrome is an inheritable arrhythmia condition that is associated with rare, loss-of-function variants in SCN5A. Interpreting the pathogenicity of SCN5A missense variants is challenging, and ≈79% of SCN5A missense variants in ClinVar are currently classified as variants of uncertain significance. Automated patch clamp technology enables high-throughput functional studies of ion channel variants and can provide evidence for variant reclassification. METHODS: An in vitro SCN5A-Brugada syndrome automated patch clamp assay was generated and independently studied at Vanderbilt University Medical Center and Victor Chang Cardiac Research Institute. The assay was calibrated according to ClinGen Sequence Variant Interpretation recommendations using high-confidence variant controls (n=49). Normal and abnormal ranges of function were established based on the distribution of benign variant assay results. Odds of pathogenicity values were derived from the experimental results according to ClinGen Sequence Variant Interpretation recommendations. The calibrated assay was then used to study SCN5A variants of uncertain significance observed in 4 families with Brugada syndrome and other arrhythmia phenotypes associated with SCN5A loss-of-function. RESULTS: Variant channel parameters generated independently at the 2 research sites showed strong correlations, including peak INa density (R2=0.86). The assay accurately distinguished benign controls (24/25 concordant variants) from pathogenic controls (23/24 concordant variants). Odds of pathogenicity values yielded 0.042 for normal function and 24.0 for abnormal function, corresponding to strong evidence for both American College of Medical Genetics and Genomics/Association for Molecular Pathology benign and pathogenic functional criteria (BS3 and PS3, respectively). Application of the assay to 4 clinical SCN5A variants of uncertain significance revealed loss-of-function for 3/4 variants, enabling reclassification to likely pathogenic. CONCLUSIONS: This validated high-throughput assay provides clinical-grade functional evidence to aid the classification of current and future SCN5A-Brugada syndrome variants of uncertain significance.
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Brugada Syndrome (BrS) is an inheritable arrhythmia condition that is associated with rare, loss-of-function variants in the cardiac sodium channel gene, SCN5A. Interpreting the pathogenicity of SCN5A missense variants is challenging and ~79% of SCN5A missense variants in ClinVar are currently classified as Variants of Uncertain Significance (VUS). An in vitro SCN5A-BrS automated patch clamp assay was generated for high-throughput functional studies of NaV1.5. The assay was independently studied at two separate research sites - Vanderbilt University Medical Center and Victor Chang Cardiac Research Institute - revealing strong correlations, including peak INa density (R2=0.86). The assay was calibrated according to ClinGen Sequence Variant Interpretation recommendations using high-confidence variant controls (n=49). Normal and abnormal ranges of function were established based on the distribution of benign variant assay results. The assay accurately distinguished benign controls (24/25) from pathogenic controls (23/24). Odds of Pathogenicity values derived from the experimental results yielded 0.042 for normal function (BS3 criterion) and 24.0 for abnormal function (PS3 criterion), resulting in up to strong evidence for both ACMG criteria. The calibrated assay was then used to study SCN5A VUS observed in four families with BrS and other arrhythmia phenotypes associated with SCN5A loss-of-function. The assay revealed loss-of-function for three of four variants, enabling reclassification to likely pathogenic. This validated APC assay provides clinical-grade functional evidence for the reclassification of current VUS and will aid future SCN5A-BrS variant classification.
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BACKGROUND: Truncating variants in filamin C (FLNC) can cause arrhythmogenic cardiomyopathy (ACM) through haploinsufficiency. Noncanonical splice-altering variants may contribute to this phenotype. OBJECTIVE: The purpose of this study was to investigate the clinical and functional consequences of a recurrent FLNC intronic variant of uncertain significance (VUS), c.970-4A>G. METHODS: Clinical data in 9 variant heterozygotes from 4 kindreds were obtained from 5 tertiary health care centers. We used in silico predictors and functional studies with peripheral blood and patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). Isolated RNA was studied by reverse transcription polymerase chain reaction. iPSC-CMs were further characterized at baseline and after nonsense-mediated decay (NMD) inhibition, using quantitative polymerase chain reaction (qPCR), RNA-sequencing, and cellular electrophysiology. American College of Medical Genetics and Genomics (ACMG) criteria were used to adjudicate variant pathogenicity. RESULTS: Variant heterozygotes displayed a spectrum of disease phenotypes, spanning from mild ventricular dysfunction with palpitations to severe ventricular arrhythmias requiring device shocks or progressive cardiomyopathy requiring heart transplantation. Consistent with in silico predictors, the c.970-4A>G FLNC variant activated a cryptic splice acceptor site, introducing a 3-bp insertion containing a premature termination codon. NMD inhibition upregulated aberrantly spliced transcripts by qPCR and RNA-sequencing. Patch clamp studies revealed irregular spontaneous action potentials, increased action potential duration, and increased sodium late current in proband-derived iPSC-CMs. These findings fulfilled multiple ACMG criteria for pathogenicity. CONCLUSION: Clinical, in silico, and functional evidence support the prediction that the intronic c.970-4A>G VUS disrupts splicing and drives ACM, enabling reclassification from VUS to pathogenic.
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Cardiomiopatias , Humanos , Cardiomiopatias/genética , Códon sem Sentido , Filaminas/genética , Mutação , Miócitos Cardíacos , RNA/genéticaRESUMO
OBJECTIVE: To examine the hypothesis that genetic variation in enzymes and transporters associated with synthesis, storage, release, and metabolism of catecholamines contributes to the interindividual variability in plasma catecholamine concentrations at rest and after exercise. METHODS: We measured plasma norepinephrine (NE) and epinephrine concentrations at rest and after a standardized exercise protocol in 165 healthy individuals (60% White, 40% African-American) and examined 29 functional or common variants in 14 genes involved in synthesis, transport, or metabolism of catecholamines. We examined the relationship between genotypes and NE concentrations at rest and the increase after exercise (ΔNE) by multiple linear regression with adjustment for covariates [age, race, sex, BMI, fitness, and resting NE (for ΔNE)]. As a secondary outcome, we carried out similar analyses for epinephrine concentrations. RESULTS: There was large interindividual variability in resting NE (mean, 204±102 pg/ml; range, 39-616 pg/ml) and ΔNE (mean, 256±206 pg/ml; range, -97 to 953 pg/ml). Resting NE was significantly associated with variants of four genes: CYB561 (P<0.001), VMAT2 (P=0.016), CHGA (P=0.039), and PNMT (P=0.038). ΔNE after exercise was associated with three variants of PNMT (P=0.041) and COMT (P=0.033 and 0.035), and resting and exercise epinephrine concentrations were associated with two variants each. CONCLUSION: The findings of this exploratory study suggest that variation in catecholamine pathway genes contributes to the interindividual variability in plasma NE and epinephrine concentrations at rest and after exercise.
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Catecolaminas/genética , Epinefrina/sangue , Redes e Vias Metabólicas , Norepinefrina/sangue , Adulto , População Negra/genética , Catecolaminas/biossíntese , Catecolaminas/metabolismo , Cromogranina A/genética , Ensaios Clínicos como Assunto , Grupo dos Citocromos b/genética , Exercício Físico/fisiologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Descanso/fisiologia , Proteínas Supressoras de Tumor/genética , Proteínas Vesiculares de Transporte de Monoamina/genética , População Branca/genéticaRESUMO
OBJECTIVE: The prevalence of subclinical coronary atherosclerosis is increased in patients with rheumatoid arthritis (RA), and the increased risk is associated with insulin resistance. Adipocytokines have been linked to obesity, insulin resistance, inflammation, and coronary heart disease in the general population. This study was undertaken to examine the hypothesis that adipocytokines affect insulin resistance and coronary atherosclerosis among patients with RA. METHODS: The coronary calcium score, homeostatic model assessment for insulin resistance (HOMA-IR) index, and serum adipocytokine (leptin, adiponectin, resistin, and visfatin) concentrations were determined in 169 patients with RA. The independent effect of each adipocytokine on insulin resistance according to the HOMA-IR index and on coronary artery calcification determined by electron beam computed tomography was assessed in models adjusted for age, race, sex, body mass index (BMI), traditional cardiovascular risk factors, and inflammation mediators. In addition, an interaction analysis was performed to evaluate whether the effect of the HOMA-IR index on the coronary calcium score is moderated by adipocytokines. RESULTS: Increased concentrations of leptin were associated with a higher HOMA-IR index, even after adjustment for age, race, sex, BMI, traditional cardiovascular risk factors, and inflammation mediators (P < 0.001), but concentrations of visfatin (P = 0.06), adiponectin (P = 0.55), and resistin (P = 0.98) showed no association with the HOMA-IR index. None of the adipocytokines was independently associated with the coronary calcium score (all P > 0.05). Serum leptin concentrations showed a significant interaction with the HOMA-IR index (P for multivariate interaction = 0.02). Increasing leptin concentrations attenuated the increased risk of coronary calcification related to insulin resistance. Serum concentrations of the other adipocytokines showed no significant interactions with the HOMA-IR index (each P > 0.05). CONCLUSION: Leptin is associated with insulin resistance in patients with RA but, paradoxically, attenuates the effects of insulin resistance on coronary calcification.
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Adipocinas/sangue , Artrite Reumatoide/sangue , Artrite Reumatoide/epidemiologia , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Resistência à Insulina , Adiponectina/sangue , Calcinose/sangue , Calcinose/epidemiologia , Cálcio/metabolismo , Citocinas/sangue , Feminino , Humanos , Mediadores da Inflamação/sangue , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Nicotinamida Fosforribosiltransferase/sangue , Prevalência , Resistina/sangue , Fatores de RiscoRESUMO
OBJECTIVE: MicroRNAs (miRNAs) regulate gene expression and are disease biomarkers. Rheumatoid arthritis (RA) patients have accelerated atherosclerosis leading to excess cardiovascular morbidity and mortality, but traditional risk factors for cardiovascular risk stratification are inadequate. In the general population, miRNAs improve cardiovascular risk estimation beyond traditional risk factors. Our objective was to develop a miRNA panel that predicts coronary atherosclerosis in RA patients. METHODS: Plasma small RNA next-generation sequencing (NGS) was performed on 161 RA patients whose Agatston scores for coronary artery calcium were previously measured. Random forest analysis of plasma NGS miRNA expression was used to determine which miRNAs best differentiated between those patients with and without coronary artery calcium. Top predictive miRNAs were assayed by quantitative PCR (qPCR). Elastic net regression was used to develop the most parsimonious models with qPCR-measured miRNA concentrations and clinical variables (age, sex, ACC/AHA 10-year risk score, DAS28 score, and diabetes) separately to predict the presence of coronary artery calcium and high coronary artery calcium. C-statistics were used to assess performance model performance. RESULTS: The top miRNAs which differentiated those with and without coronary atherosclerosis based on random forest analysis included let-7c-5p, miR-30e-5p, miR-30c-5p, miR-4446-3p, miR-126-5p, miR-3168, miR-425-5p, miR-126-3p, miR-30a-5p, and miR-125a-5p. For coronary artery calcium prediction, addition of all miRNAs except miR-126-3p to clinical factors improved the c-statistic modestly from 0.86 to 0.87. For high coronary artery calcium prediction, addition of all miRNAs except miR-30c-5p to clinical factors improved the c-statistic from 0.75 to 0.80. CONCLUSION: A plasma miRNA panel improved the prediction of high coronary artery calcium beyond traditional risk factors and RA disease activity. Further evaluation of the miRNA panel for prediction of coronary events in RA is necessary. Key Point ⢠A plasma microRNA panel including let-7c-5p, miR-30a-5p, miR-30e-5p, miR-125a-5p, miR-126-3p, miR-126-5p, miR-425-5p, miR-3168, and miR-4446-3p improved the prediction of high coronary artery calcium beyond clinical factors in patients with rheumatoid arthritis.
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Artrite Reumatoide , Doença da Artéria Coronariana , MicroRNAs , Artrite Reumatoide/complicações , Artrite Reumatoide/genética , Doença da Artéria Coronariana/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Fatores de RiscoRESUMO
OBJECTIVE: Small RNA (sRNA) sequencing has revealed new sRNA classes beyond microRNAs (miRNAs). These sRNAs can regulate genes and act as biomarkers. The aim of this study was to determine if the endogenous plasma sRNA landscape is altered in patients with rheumatoid arthritis (RA) compared with control subjects and to determine its association with disease-related parameters in RA. METHODS: sRNA sequencing was performed on plasma from 165 RA and 90 control subjects who were frequency-matched for age, race, and sex. Endogenous sRNAs, such as miRNAs, isomiRs, sRNAs derived from small nuclear RNAs (snDRs), small nucleolar RNAs (snoDRs), Y RNAs (yDRs), transfer-derived RNAs (tDRs), long noncoding RNAs (lncDRs) as well as miscellaneous sRNAs (miscRNAs), were quantified using Tools for Integrative Genome analysis of Extracellular sRNAs (TIGER). Individual and categories of sRNAs were compared between RA and controls, and significantly altered sRNAs and sRNA categories were correlated with disease activity and general laboratory measures in RA. RESULTS: Patients with RA had more miRNAs (1.42-fold, P = 0.01), more tDRs (1.14-fold, P = 0.04), and fewer yDRs (-1.41-fold, P = 0.009) compared with control subjects. Disease duration was inversely associated with yDRs. Disease-related parameters, such as Disease Activity Score-28 (DAS28), swollen joint count, and inflammatory markers were significantly positively associated with tDRs and miscRNAs, and miR-22-3p and related sequences and isomiRs were most significantly associated with DAS28. CONCLUSION: Endogenous plasma sRNAs are altered in RA compared with control subjects. Although individual miRNAs have been well studied and many are excellent biomarkers in RA, several non-miRNA sRNAs were significantly associated with disease-related parameters as classes and may represent novel biomarkers for RA.
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OBJECTIVE: MicroRNA (miRNA) are short noncoding RNA that regulate genes and are both biomarkers and mediators of disease. We used small RNA (sRNA) sequencing and machine learning methodology to develop an miRNA panel to reliably differentiate between rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) and control subjects. METHODS: Plasma samples from 167 RA and 91 control subjects who frequency-matched for age, race, and sex were used for sRNA sequencing. TIGER was used to analyze miRNA. DESeq2 and random forest analyses were used to identify a prioritized list of miRNA differentially expressed in patients with RA. Prioritized miRNA were validated by quantitative PCR, and lasso and logistic regression were used to select the final panel of 6 miRNA that best differentiated RA from controls. The panel was validated in a separate cohort of 12 SLE, 32 RA, and 32 control subjects. Panel efficacy was assessed by area under the receiver operative characteristic curve (AUC) analyses. RESULTS: The final panel included miR-22-3p, miR-24-3p, miR-96-5p, miR-134-5p, miR-140-3p, and miR-627-5p. The panel differentiated RA from control subjects in discovery (AUC = 0.81) and validation cohorts (AUC = 0.71), seronegative RA (AUC = 0.84), RA remission (AUC = 0.85), and patients with SLE (AUC = 0.80) versus controls. Pathway analysis showed upstream regulators and targets of panel miRNA are associated with pathways implicated in RA pathogenesis. CONCLUSION: An miRNA panel identified by a bioinformatic approach differentiated between RA or SLE patients and control subjects. The panel may represent an autoimmunity signature, perhaps related to inflammatory arthritis, which is not dependent on active disease or seropositivity.
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Artrite Reumatoide/sangue , Biologia Computacional/métodos , Lúpus Eritematoso Sistêmico/sangue , MicroRNAs/sangue , MicroRNAs/genética , Adulto , Área Sob a Curva , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Análise de Sequência de RNARESUMO
Patients with systemic lupus erythematosus (SLE) have accelerated atherosclerosis, but the underlying mechanisms are unclear. The size and number of lipoprotein particles may be better predictors of atherosclerosis than conventional cholesterol measurements. We measured lipoprotein subclasses by nuclear magnetic resonance spectroscopy (NMR), coronary artery calcification by electron beam computed tomography, and insulin resistance by homeostasis model assessment in 105 patients with SLE and 77 control subjects. VLDL particles were larger (50.0+/-8.5 versus 47.7+/-8.5 nm, P=0.01) and concentrations of large high-density lipoprotein (HDL) particles lower (10.1+/-5.3 versus 11.3+/-5.1 nmol/L, P=0.03) in patients with SLE than controls. In patients with SLE, small LDL concentration was associated with body mass index (rho=0.27), insulin resistance (rho=0.34), C-reactive protein (CRP; rho=0.30), and erythrocyte sedimentation rate (ESR; rho=0.20); all P<0.05. Large HDL concentration was inversely associated with insulin resistance (rho=-0.29), disease activity (rho=-0.23), and ESR (rho=-0.39); all P<0.05. VLDL concentrations correlated with CRP (rho=0.22), ESR (rho=0.24), disease damage (rho=0.20), and corticosteroid exposure (rho=0.29); all P<0.05. Neither the concentration of lipoprotein subclasses nor particle size was associated with coronary artery atherosclerosis. There were only minor differences in the NMR lipid profiles of patients with SLE and controls. Lipoprotein subclasses were associated with metabolic variables, inflammatory markers, and corticosteroid use but not with coronary artery atherosclerosis in SLE.
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Aterosclerose/sangue , Lipoproteínas/sangue , Lúpus Eritematoso Sistêmico/sangue , Adulto , Aterosclerose/complicações , Estudos de Casos e Controles , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
Hypertension is highly prevalent in patients with rheumatoid arthritis (RA). In other populations, high sodium (Na+) and low potassium (K+) intake are associated with an increased risk of hypertension, and in animal models, a high salt intake exacerbated arthritis. Patients with RA have many comorbidities associated with salt sensitivity, but their salt intake and its relationship to blood pressure and inflammation is unknown. Using the Kawasaki formula, Na+ and K+ urinary excretion (reflecting intake) was estimated in 166 patients with RA and 92 controls, frequency matched for age, sex, and race. Inflammatory markers and disease activity were measured in RA patients. We tested the associations between blood pressure and Na+ and K+ excretion. Estimated 24-h Na+ excretion was similarly high in both RA (median [IQR] 5.1 g, [3.9-6.6 g]) and controls (4.9 g, [4.0-6.5 g]), p = 0.9, despite higher rates of hypertension in RA (54 vs. 39%, p = 0.03). The Na+:K+ excretion ratio was significantly higher in RA (2.0 [1.6-2.4]) vs. 1.7 [1.5-2.1]), p = 0.02] compared to controls. In RA, a lower K+ excretion was inversely correlated with diastolic blood pressure (adjusted ß = - 1.79, p = 0.04). There was no significant association between Na+ or K+ excretion and inflammatory markers. Despite a similar Na+ excretion, patients with RA had higher rates of hypertension than controls, a finding compatible with increased salt sensitivity. Patients with RA had a lower Na+:K+ excretion ratio than controls, and lower K+ excretion was associated with higher diastolic blood pressure in RA.
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Artrite Reumatoide/urina , Pressão Sanguínea/fisiologia , Hipertensão/urina , Inflamação/urina , Potássio/urina , Sódio/urina , Adulto , Idoso , Artrite Reumatoide/complicações , Artrite Reumatoide/fisiopatologia , Biomarcadores , Creatinina/urina , Feminino , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Inflamação/complicações , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Telomeres protect against chromosomal end damage and shorten with each cell division; their length may be a marker of cardiovascular and overall biological aging. We examined the hypothesis that reduced telomere length is associated with increased coronary atherosclerosis in rheumatoid arthritis (RA). METHODS: We performed a cross-sectional study in 145 patients with RA and 87 control subjects frequency-matched for age, race, and sex. Coronary artery calcium score was determined by noncontrast cardiac computed tomography. Telomere length was measured from whole blood DNA, using real-time quantitative polymerase chain reaction and expressed as telomeric product to a single-copy gene product ratio (T/S ratio). Associations between telomere length, coronary artery calcium score, and 28-joint Disease Activity Score (DAS28) were assessed with Spearman correlation, proportional odds logistic regression, and linear regression, adjusting for age, race, and sex. RESULTS: Telomere length was significantly inversely correlated with age in patients with RA (ρ = -0.37, p < 0.001) and control subjects (ρ = -0.39, p = 0.001). Among patients with RA, for every interquartile range (IQR) decrease in telomere length (T/S ratio), the odds of higher coronary artery calcium score increased by 38% (95% CI: 4-60) after adjusting for age, race, and sex (p adjusted = 0.03). Telomere length was not associated with DAS28 (p adjusted = 0.17). Telomere length was not significantly different in patients with RA [median (IQR): 1.02 units (0.9-1.11)] compared to control subjects [1.05 units (0.95-1.17); p = 0.10]. CONCLUSION: Telomere length is inversely associated with coronary artery calcium score, independent of age, race, and sex in patients with RA.
Assuntos
Artrite Reumatoide/complicações , Aterosclerose/etiologia , Doença da Artéria Coronariana/etiologia , Encurtamento do Telômero/fisiologia , Telômero , Envelhecimento/genética , Envelhecimento/metabolismo , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Biomarcadores , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Patients with rheumatoid arthritis (RA) have an increased risk of coronary heart disease (CHD). Some RA therapies may modify this risk, but the underlying mechanisms are unclear. The cholesterol efflux capacity of high-density lipoprotein (HDL) is associated with a reduced CHD risk in non-RA populations; however, inflammation may impair the function of HDL. The aim of this study was to evaluate whether reduced inflammation resulting from treatment with methotrexate (MTX), adalimumab (ADA), or tocilizumab (TCZ) would increase the net cholesterol efflux capacity of HDL in patients with RA. METHODS: A longitudinal multicenter study repository (Treatment Efficacy and Toxicity in Rheumatoid Arthritis Database and Repository) provided clinical information for and serum samples from 70 patients with RA before and 6 months after starting treatment with a new drug (MTX [n = 23], ADA [n = 22], or TCZ [n = 25]). Disease activity was measured using the Disease Activity Score in 28 joints using the erythrocyte sedimentation rate (DAS28-ESR). The net cholesterol efflux capacity was measured in paired serum samples using THP-1 macrophages, and total cellular cholesterol was measured by fluorometric assay. RESULTS: The DAS28-ESR decreased with all treatments (P < 0.001). Net cholesterol efflux capacity was not significantly changed after 6 months of new RA therapy (mean ± SD 36.9 ± 17.3% units at baseline versus 38.0% ± 16.9% units at 6 months [P = 0.58]). However, change in net cholesterol efflux capacity was associated with change in the DAS28-ESR (ρ = -0.25, P = 0.04). In a post hoc analysis of patients with impaired net cholesterol efflux capacity at baseline, treatment with TCZ resulted in significant improvement in net cholesterol efflux capacity (21.9 ± 14.7% units at baseline versus 31.3% ± 12.8% units at 6 months [P < 0.02]), but this was not observed with MTX or ADA. CONCLUSION: Net cholesterol efflux capacity of HDL cholesterol did not change significantly after 6 months of new RA therapy, except in patients with impaired baseline cholesterol efflux capacity who were receiving TCZ. Change in disease activity was associated with change in the net cholesterol efflux capacity.
Assuntos
Adalimumab/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Colesterol/metabolismo , Lipoproteínas HDL/fisiologia , Metotrexato/uso terapêutico , Adalimumab/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Antirreumáticos/farmacologia , Transporte Biológico/efeitos dos fármacos , Sedimentação Sanguínea , Feminino , Humanos , Estudos Longitudinais , Masculino , Metotrexato/farmacologia , Pessoa de Meia-Idade , SoroRESUMO
OBJECTIVE: Patients with rheumatoid arthritis (RA) have increased risk of atherosclerotic cardiovascular disease that is underestimated by the Framingham Risk Score (FRS). We undertook this study to test the hypothesis that the 2013 American College of Cardiology/American Heart Association (ACC/AHA) 10-year risk score would perform better than the FRS and the Reynolds Risk Score (RRS) in identifying RA patients known to have elevated cardiovascular risk based on high coronary artery calcification (CAC) scores. METHODS: Among 98 RA patients eligible for risk stratification using the ACC/AHA risk score, we identified 34 patients with high CAC (defined as ≥300 Agatston units or ≥75th percentile of expected coronary artery calcium for age, sex, and ethnicity) and compared the ability of the 10-year FRS, RRS, and ACC/AHA risk scores to correctly assign these patients to an elevated risk category. RESULTS: All 3 risk scores were higher in patients with high CAC (P < 0.05). The percentage of patients with high CAC correctly assigned to the elevated risk category was similar among the 3 scores (FRS 32%, RRS 32%, ACC/AHA risk score 41%) (P = 0.223). The C statistics for the FRS, RRS, and ACC/AHA risk score predicting the presence of high CAC were 0.65, 0.66, and 0.65, respectively. CONCLUSION: The ACC/AHA 10-year risk score does not offer any advantage compared to the traditional FRS and RRS in the identification of RA patients with elevated risk as determined by high CAC. The ACC/AHA risk score assigned almost 60% of patients with high CAC to a low risk category. Risk scores and standard risk prediction models used in the general population do not adequately identify many RA patients with elevated cardiovascular risk.
Assuntos
Artrite Reumatoide/metabolismo , Calcificação Fisiológica/fisiologia , Cálcio/metabolismo , Doenças Cardiovasculares/epidemiologia , Vasos Coronários/metabolismo , Adulto , Idoso , American Heart Association , Artrite Reumatoide/fisiopatologia , Biomarcadores/metabolismo , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Estados UnidosRESUMO
INTRODUCTION: GlycA is a novel inflammatory biomarker measured using nuclear magnetic resonance (NMR). Its NMR signal primarily represents glycosylated acute phase proteins. GlycA was associated with inflammation and development of cardiovascular disease in initially healthy women. We hypothesized that GlycA is a biomarker of disease activity and is associated with coronary artery atherosclerosis in patients with rheumatoid arthritis (RA). METHODS: We conducted a cross-sectional study of 166 patients with RA and 90 control subjects. GlycA was measured from an NMR signal originating from N-acetylglucosamine residues on circulating glycoproteins. The relationship between GlycA and RA disease activity (Disease Activity Score based on 28 joints (DAS28)) and coronary artery calcium score was determined. RESULTS: GlycA concentrations were higher in patients with RA (median (interquartile range): 398 µmol/L (348 to 473 µmol/L)) than control subjects (344 µmol/L (314 to 403 µmol/L) (P < 0.001). In RA, GlycA was strongly correlated with DAS28 based on erythrocyte sedimentation rate (DAS28-ESR) and DAS28 based on C-reactive protein (DAS28-CRP) and their components, including tender and swollen joint counts, global health score, ESR and CRP (all P < 0.001). The area under the receiver operating characteristic curve for GlycA's ability to differentiate between patients with low versus moderate to high disease activity based on DAS28-CRP was 0.75 (95% confidence interval (CI): 0.68, 0.83). For each quartile increase in GlycA, the odds of having coronary artery calcium increased by 48% (95% CI: 4%, 111%), independent of age, race and sex (P = 0.03). CONCLUSION: GlycA is a novel inflammatory marker that may be useful for assessment of disease activity and is associated with coronary artery atherosclerosis in patients with RA.
Assuntos
Artrite Reumatoide/patologia , Biomarcadores/análise , Doença da Artéria Coronariana/patologia , Espectroscopia de Ressonância Magnética/métodos , Área Sob a Curva , Artrite Reumatoide/complicações , Doença da Artéria Coronariana/etiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROCRESUMO
Elevated concentrations of inflammatory mediators are characteristic of autoimmune disease accompanied by chronic or recurrent inflammation. We examined the hypothesis that mediators of inflammation known to be elevated in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are associated with genetic polymorphism previously identified in studies of inflammatory disease. Serum interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) concentrations in patients with SLE (n = 117) or RA (n = 164) and in inflammatory disease-free control subjects (n = 172) were measured by multiplex ELISA. Candidate genes were chosen from studies of autoimmune and inflammatory disease. Genotypes were determined for 345 SNP markers in 75 genes. Association between serum analytes and single alleles was tested by linear regression. Polymorphisms in several genes were associated with IL-6 levels (including IL10, TYK2, and CD40L in SLE and DRB1, NOD2, and CSF1 in RA) or with TNFα levels (including TNFSF4 and CSF2 in SLE and PTPN2, DRB1, and NOD2 in RA). Some associations were shared between disease and control groups or between IL-6 and TNFα within a group. In conclusion, variation in genes implicated in disease pathology is associated with serum IL-6 or TNFα concentration. Some genetic associations are more apparent in healthy controls than in SLE or RA, suggesting dysregulation of the principal mediators of chronic inflammation in disease. Susceptibility genes may affect inflammatory response with variable effect on disease etiology.