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Biomedical subjects

Arshed A Quyyumi

Publications and source records attributed to Arshed A Quyyumi.

At least 19 recordsLinked to original sources

Multi-ancestry genetic architecture of heart failure subtypes.

Heart failure (HF) affects 6.7 million people in the US and includes two major subtypes, HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), with distinct genetic architectures. We meta-analyze genome-wide association studies (GWAS) of 38,781 HFrEF cases, 38,163 HFpEF cases, and 526,135 controls across European, African, Hispanic, and Asian ancestries using the Million Veteran Program and Vanderbilt University DNA Databank (BioVU). We identify 46 genome-wide significant loci for HFrEF (9 novel) and 3 loci for HFpEF (1 novel). Four HFrEF loci are detected in African ancestry participants near CD36, SPI1, TRIM48, and SPNS3, with lead SNPs showing low risk-allele frequencies in European populations. In the all-cause HF meta-analysis (200,070 cases, 2,076,466 controls), we identify 136 loci (12 novel). Gene-based tests, tissue enrichment, transcriptome-wide association, and fine-mapping implicate vascular, metabolic, and TGF-β/Smad signaling pathways and nominate candidate causal genes, clarifying shared and subtype-specific risk across ancestries.

Humans↗

Proteomics-Based Soluble Urokinase Plasminogen Activator Receptor Levels Are Associated With Adverse Cardiovascular Outcomes in the General Population: Insights From the UK Biobank.

BACKGROUND: Elevated soluble urokinase plasminogen activator receptor (suPAR) levels are associated with inflammation, immune activation, and major adverse cardiovascular events in coronary artery disease. Encoded by the PLAUR gene, suPAR levels are influenced by the rs4760 genetic variant. Whether proteomics-based suPAR levels predict adverse outcomes in the general population remains unknown. METHODS: Proteomics-based suPAR levels were measured using the Olink Immunoassay in 33&#x2009;963 UK Biobank participants without known coronary artery disease. Fine-Gray and Cox proportional hazards models assessed associations between suPAR and major adverse cardiovascular events (primary outcome: cardiovascular mortality, nonfatal myocardial infarction, or stroke), cardiovascular mortality, and all-cause mortality (secondary outcomes), after adjustment for demographic and clinical risk factors, hs-CRP (high-sensitivity C-reactive protein), and the rs4760 variant. Incremental discrimination was evaluated using C-statistics. RESULTS: Participants were aged 56.4 (SD, 8.2) years; 45% were men, and 93.4% were White. Over a median follow-up of 14&#x2009;years (476&#x2009;177 person-years), 10.7% experienced major adverse cardiovascular events, 2.6% experienced cardiovascular mortality, and 9.4% experienced all-cause mortality. Each 1-SD increment in proteomics-based suPAR was associated with significantly higher risk of major adverse cardiovascular events (hazard ratio [HR], 3.2 [95% CI, 2.9-4.5]), cardiovascular mortality (HR, 5.9 [95% CI, 5.1-6.9]), and all-cause mortality (HR, 5.0 [95% CI, 4.6-5.5]), independent of clinical risk factors and hs-CRP. Additional adjustment for rs4760 did not attenuate these associations. Proteomics-based suPAR significantly improved discrimination beyond clinical risk factors (C-statistic: 0.719 versus 0.732; P<0.001). CONCLUSIONS: Proteomics-based suPAR independently predicts adverse cardiovascular outcomes in the general population, beyond conventional risk factors, hs-CRP, and genetic predisposition to elevated suPAR levels.

Humans↗

The relationship between plasma levels of oxidized and reduced thiols and early atherosclerosis in healthy adults.

OBJECTIVES: The study investigated the relationship between biomarkers of oxidative stress and early atherosclerosis. BACKGROUND: Oxidative stress is an important etiologic factor in the pathogenesis of vascular disease. We hypothesized that oxidative stress would predict early atherosclerosis in a relatively healthy population. METHODS: One hundred fourteen healthy non-smokers, without known clinical atherosclerosis, had carotid intima-media thickness (IMT) measured using ultrasound. Oxidative stress was estimated by measuring plasma levels of: 1) glutathione (GSH), an important intracellular antioxidant thiol, its oxidized disulfide form (GSSG), and their redox state (E(h) GSH/GSSG), and 2) cysteine (Cys), an important extracellular antioxidant thiol, its oxidized disulfide form cystine (CySS), and their redox state (E(h)Cys/CySS). RESULTS: The univariate predictors of IMT were age, body mass index, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein (hs-CRP), and Framingham risk score. Intima-media thickness was also higher in males and hypertensive subjects. Among the oxidative stress markers, GSH (r = -0.39, p < 0.0001), CySS (r = 0.18, p = 0.049), and E(h) GSH/GSSG (r = 0.34, p < 0.0002) correlated with IMT. After adjusting for traditional risk factors and hs-CRP, only E(h) GSH/GSSG remained an independent predictor of IMT. E(h) GSH/GSSG predicted IMT in a manner that was both independent of and additive to Framingham risk score. CONCLUSIONS: Glutathione redox state (E(h) GSH/GSSG), an in vivo measure of intracellular oxidative stress, is an independent predictor for the presence of early atherosclerosis in an otherwise healthy population. This finding supports a role for oxidative stress in the pathogenesis of premature atherosclerosis, and its measurement may help in the early identification of asymptomatic subjects at risk of atherosclerotic disease.

Adult↗

Women and ischemic heart disease: pathophysiologic implications from the Women's Ischemia Syndrome Evaluation (WISE) Study and future research steps.

The current review highlights gender-specific issues in ischemic heart disease (IHD) presentation, evaluation, and outcomes with a special focus on the results derived from the National Institutes of Health-National Heart, Lung, and Blood Institute-sponsored Women's Ischemia Syndrome Evaluation (WISE) study. New evidence on gender-based differences in vascular wall, atherosclerotic plaque deposition, pathophysiology, and innovative cardiovascular imaging techniques are reviewed. Critical areas of further inquiry needed to advance new gender-specific IHD understanding are detailed.

Coronary Artery Disease↗

Insights from the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study: Part II: gender differences in presentation, diagnosis, and outcome with regard to gender-based pathophysiology of atherosclerosis and macrovascular and microvascular coronary disease.

Coronary heart disease is the leading cause of death and disability in the U.S., but recent advances have not led to declines in case fatality rates for women. The current review highlights gender-specific issues in ischemic heart disease (IHD) presentation, evaluation, and outcomes with a special focus on the results derived from the National Institutes of Health-National Heart, Lung, and Blood Institute-sponsored Women's Ischemia Syndrome Evaluation (WISE) study. In the second part of this review, we will assess new evidence on gender-based differences in vascular wall or metabolic alterations, atherosclerotic plaque deposition, and functional expression on worsening outcomes of women. Additionally, innovative cardiovascular imaging techniques will be discussed. Finally, we identify critical areas of further inquiry needed to advance this new gender-specific IHD understanding into improved outcomes for women.

Atherosclerosis↗

Insights from the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE) Study: Part I: gender differences in traditional and novel risk factors, symptom evaluation, and gender-optimized diagnostic strategies.

Despite a dramatic decline in mortality over the past three decades, coronary heart disease is the leading cause of death and disability in the U.S. Importantly, recent advances in the field of cardiovascular medicine have not led to significant declines in case fatality rates for women when compared to the dramatic declines realized for men. The current review highlights gender-specific issues in ischemic heart disease presentation, evaluation, and outcomes with a special focus on the results published from the National Institutes of Health-National Heart, Lung, and Blood Institute-sponsored Women's Ischemia Syndrome Evaluation (WISE) study. We will present recent evidence on traditional and novel risk markers (e.g., high sensitivity C-reactive protein) as well as gender-specific differences in symptoms and diagnostic approaches. An overview of currently available diagnostic test evidence (including exercise electrocardiography and stress echocardiography and single-photon emission computed tomographic imaging) in symptomatic women will be presented as well as data using innovative imaging techniques such as magnetic resonance subendocardial perfusion, and spectroscopic imaging will also be discussed.

Female↗

A variant of the gene encoding leukotriene A4 hydrolase confers ethnicity-specific risk of myocardial infarction.

Variants of the gene ALOX5AP (also known as FLAP) encoding arachidonate 5-lipoxygenase activating protein are known to be associated with risk of myocardial infarction. Here we show that a haplotype (HapK) spanning the LTA4H gene encoding leukotriene A4 hydrolase, a protein in the same biochemical pathway as ALOX5AP, confers modest risk of myocardial infarction in an Icelandic cohort. Measurements of leukotriene B4 (LTB4) production suggest that this risk is mediated through upregulation of the leukotriene pathway. Three cohorts from the United States also show that HapK confers a modest relative risk (1.16) in European Americans, but it confers a threefold larger risk in African Americans. About 27% of the European American controls carried at least one copy of HapK, as compared with only 6% of African American controls. Our analyses indicate that HapK is very rare in Africa and that its occurrence in African Americans is due to European admixture. Interactions with other genetic or environmental risk factors that are more common in African Americans are likely to account for the greater relative risk conferred by HapK in this group.

Black or African American↗

Increased circulating endothelial progenitor cells are associated with survival in acute lung injury.

RATIONALE: Repair of damaged endothelium is important in recovery from acute lung injury. In animal models, bone marrow-derived endothelial progenitor cells differentiate into mature endothelium and assist in repairing damaged vasculature. OBJECTIVES: The quantity of endothelial progenitor cells in patients with acute lung injury is unknown. We hypothesize that increased numbers of circulating endothelial progenitor cells will be associated with an improved outcome in acute lung injury and the acute respiratory distress syndrome. METHODS: Peripheral blood mononuclear cells from the buffy coat of patients with early acute lung injury (n=45), intubated control subjects (n=10), and healthy volunteers (n=7) were isolated using Ficoll density gradient centrifugation, and plated on fibronectin-coated cellware. After 24 hours, nonadherent cells were removed and replated on fibronectin-coated cellware at a concentration of 1x10(6) cells/well. Colony-forming units were counted after 7 days' incubation. MEASUREMENTS/MAIN RESULTS: Endothelial progenitor cell colony numbers were significantly higher in patients with acute lung injury compared with healthy control subjects (p<0.05), but did not differ between patients with acute lung injury and intubated control subjects. However, in the 45 patients with acute lung injury, improved survival correlated with a higher colony count (p<0.04). Patients with acute lung injury with a colony count of >or= 35 had a mortality of 30%, compared with 61% in those with colony counts <35 (p<0.03), results that persisted in a multivariable analysis correcting for age, sex, and severity of illness. CONCLUSIONS: An increased number of circulating endothelial progenitor cells in acute lung injury is associated with improved survival.

Adult↗

Association between novel oxidative stress markers and C-reactive protein among adults without clinical coronary heart disease.

OBJECTIVE: Increases in the inflammatory marker C-reactive protein (CRP) have been associated with a higher risk of incident coronary heart disease (CHD). The causes of increased CRP, however, are not completely understood. Studies suggest that oxidative stress may have pro-inflammatory effects, but data on the relationship between oxidative stress and CRP in healthy persons is sparse. METHODS AND RESULTS: We conducted a cross-sectional study of oxidative stress markers and high sensitivity CRP (hsCRP) among 126 adults without CHD. Markers of oxidative stress included the free oxygen radical test (FORT), which reflects levels of organic hydroperoxides, and the redox potential of the reduced glutathione/glutathione disulfide couple, (Eh) GSH/GSSG. In a linear regression model that adjusted for age, sex, body mass index, and other potential hsCRP determinants, the FORT was positively associated with log-transformed hsCRP and explained 14% of log-transformed hsCRP variance (P < 0.001). In contrast, (Eh) GSH/GSSG showed little association with hsCRP. CONCLUSIONS: Among adults free of CHD, oxidative stress, as measured by the FORT, is significantly associated with higher hsCRP levels, independent of BMI and other CRP determinants. This result suggests that oxidative stress may be a determinant of CRP levels and promote pro-atherosclerotic inflammatory processes at the earliest stages of CHD development.

Adult↗

Circulating endothelial progenitor cells as novel biological determinants of vascular function and risk.

Endothelial progenitor cells (EPCs) are found in circulating mononuclear cells, bone marrow and cord blood, and have been shown to incorporate into areas of postnatal neovascularization stimulated by either ischemia or endothelial denudation. Endothelial cell injury is a hallmark of atherosclerotic plaque development triggered by a variety of cardiovascular risk factors, and the magnitude of endothelial dysfunction appears to be an independent predictor of cardiovascular risk. Several investigations have discovered that circulating levels of EPCs are diminished in individuals with cardiovascular risk factors which raises the possibility that this may contribute to endothelial dysfunction by impairing endothelial repair. In a study of adult men, it was found that the circulating EPC count was reduced in patients with multiple cardiovascular risk factors. Moreover, endothelial dysfunction was strongly correlated with EPC counts, such that subjects with risk factors developed endothelial dysfunction only if the EPC counts were low. EPCs of subjects with endothelial dysfunction were more senescent compared with an age-matched group without risk factors. These and other recent observations from experimental studies raise the possibility that vascular disease and dysfunction occur where injury is inflicted by exposure to risk factors in a setting of impaired repair capacity due to reduced availability of EPCs.

Journal Article↗

Association of serum antibodies to heat-shock protein 65 with coronary calcification levels: suggestion of pathogen-triggered autoimmunity in early atherosclerosis.

BACKGROUND: Previous studies demonstrated an association between antibodies to mycobacterial heat-shock protein 65 (mHSP65) and carotid artery thickening. We examined whether mHSP65 antibodies are associated with levels of coronary calcification that appear to reflect preclinical coronary artery disease (CAD). METHODS AND RESULTS: Serum specimens from 201 healthy asymptomatic subjects (52% male; mean age, 56.6 years) undergoing electron-beam computed tomographic imaging were used to measure levels of mHSP65 and human HSP60 antibodies and antibodies to several infectious pathogens. We found that 84% of the study subjects had anti-mHSP65 IgG antibodies. Mean titers of mHSP65 antibodies were higher (1:394 versus 1:267, P=0.012) in individuals with than in those without elevated levels of coronary calcium (calcium score > or =150). Increasing titers of mHSP65 antibodies were significantly associated, in a dose-response manner, with elevated levels of coronary calcification. Individuals with the highest titers of mHSP65 antibodies (> or =1:800) had an adjusted odds ratio (OR) of 14.3 for having elevated coronary calcium (P=0.004). Association of mHSP65 antibodies with elevated coronary calcification levels was independent of CAD risk factors after multivariate adjustment (P=0.037). Interestingly, mHSP65 antibody titers were correlated with Helicobacter pylori infection (P=0.004), which maintained significance after adjustment for CAD risk factors and seropositivities to other pathogens (adjusted OR, 3.1; 95% CI, 1.4 to 6.6). No association was found between antibodies to human HSP60 and levels of coronary calcification. CONCLUSIONS: Antibodies to mHSP65 are associated with elevated levels of coronary calcification and correlated with H pylori infection, suggesting that pathogen-triggered autoimmunity plays a role in early atherosclerosis.

Adult↗

Prognostic value of endothelial function.

The term endothelial dysfunction most commonly refers to impairment of endothelium-dependent vasodilation and implies presence of widespread abnormalities in endothelial integrity and homeostasis. This phenomenon, which can be measured by a number of invasive and noninvasive techniques, often marks an early stage in atherosclerosis and can be observed in coronary and peripheral arterial beds. Studies demonstrate that endothelial dysfunction in the coronary resistance or conductance vessels predict both hard (eg, acute ischemic events) and soft (eg, coronary revascularization) outcomes. Other studies demonstrate that endothelial dysfunction of the brachial artery also carries prognostic relevance for risk of coronary events. However, these studies included selected high-risk populations. Data are lacking on the prognostic value of endothelial dysfunction in low-risk populations. Further, the data do not permit the use of improvement in endothelial dysfunction as a surrogate marker for risk reduction. Nevertheless, assessment of endothelial function is a valuable research tool and, with further refinement, promises to be an important aid in applying the science of vascular biology to clinical practice.

Arteriosclerosis↗

Increased serum levels of heat shock protein 70 are associated with low risk of coronary artery disease.

OBJECTIVE: Previous studies suggest that heat shock protein (HSP) 60 has a contributory role in atherosclerosis development. We examined whether circulating HSP70 protein and anti-HSP70 antibodies are associated with coronary artery disease (CAD). METHODS AND RESULTS: Blood samples from 421 patients (62% men, mean age 57 years) evaluated for CAD by coronary angiography were tested. Serum HSP70 was detectable in 67% of study subjects with levels ranging from 0.2 to 27.1 ng/mL (mean, 1.08; median, 0.5). HSP70 levels were higher in non-CAD patients than CAD patients (median, 0.72 versus 0.34; P=0.0006). Individuals with HSP70 levels above the median (0.5 ng/mL) had half the risk of CAD than individuals with levels below the median (adjusted odds ratio, 0.52; 95% confidence limit, 0.32 to 0.86). The association of high HSP70 levels with low CAD risk was independent of traditional CAD risk factors (P=0.011). Disease severity (number of diseased vessels) was also inversely associated with HSP70 protein levels (P=0.010). The adjusted odds ratio of having multivessel disease for patients with high HSP70 protein levels was 0.54 (95% confidence limit, 0.36 to 0.81). In contrast, no association between anti-HSP70 IgG seropositivity and the prevalence of CAD was found (P=0.916). CONCLUSIONS: These data provide the first evidence that high levels of human HSP70 are associated with the low CAD risk, probably through its multiple protective effects on a cell's response to stress.

Adult↗

Circulating endothelial progenitor cells, vascular function, and cardiovascular risk.

BACKGROUND: Cardiovascular risk factors contribute to atherogenesis by inducing endothelial-cell injury and dysfunction. We hypothesized that endothelial progenitor cells derived from bone marrow have a role in ongoing endothelial repair and that impaired mobilization or depletion of these cells contributes to endothelial dysfunction and cardiovascular disease progression. METHODS: We measured the number of colony-forming units of endothelial progenitor cells in peripheral-blood samples from 45 men (mean [+/-SE] age, 50+/-2 years). The subjects had various degrees of cardiovascular risk but no history of cardiovascular disease. Endothelium-dependent and endothelium-independent function was assessed by high-resolution ultrasonography of the brachial artery. RESULTS: We observed a strong correlation between the number of circulating endothelial progenitor cells and the subjects' combined Framingham risk factor score (r=-0.47, P=0.001). Measurement of flow-mediated brachial-artery reactivity also revealed a significant relation between endothelial function and the number of progenitor cells (r=0.59, P<0.001). Indeed, the levels of circulating endothelial progenitor cells were a better predictor of vascular reactivity than was the presence or absence of conventional risk factors. In addition, endothelial progenitor cells from subjects at high risk for cardiovascular events had higher rates of in vitro senescence than cells from subjects at low risk. CONCLUSIONS: In healthy men, levels of endothelial progenitor cells may be a surrogate biologic marker for vascular function and cumulative cardiovascular risk. These findings suggest that endothelial injury in the absence of sufficient circulating progenitor cells may affect the progression of cardiovascular disease.

Adult↗