Reference interval establishment and correlation research of urine thromboxane metabolites: Unveiling new possibilities in platelet activation.

BACKGROUND: Thromboxane metabolites could indirectly reflect platelet activation, among which 11-dehydro-thromboxane B2 (11dhTxB2) and 11-dehydro-2, 3-dinor thromboxane B2 (11dh23dinorTxB2) are two stable metabolites that are abundant in urine, and both are closely related to disease progression and drug use. However, most clinical application studies have focused on the single indicator of 11dhTxB2. We propose an LC-MS/MS method suitable for routine clinical screening with simultaneous determination of both metabolites and conduct preliminary studies in different populations. METHODS AND RESULTS: The thromboxane metabolites were extracted by liquid-liquid extraction and determined by LC-MS/MS. Reference intervals (RI) were established in 333 healthy adults and validated in 25 patients with coronary atherosclerosis (CA). This LC-MS/MS method was over a wide quantitative range (0.1-10 µmol/L), the imprecision and accuracy were 5.2 %-11 % and 89.3 %-106.5 %, and was suitable for clinical routine quantitative screening. The 95th percentile RI of unire 11dhTxB2 was 1220 (95 % CI: 1048, 1376) pg mg Cr -1, for 11dh23dinorTxB2, RI was 908 (95 % CI: 821, 1102) pg mg Cr -1. For the first time, we found a significant correlation between 11dhTxB2 and 11dh23dinorTxB2 in both healthy adults (r = 0.67, P < 0.001) and CA patients (r = 0.77, P < 0.001). CONCLUSION: The establishment of RI provides a reference for diseases related to platelet activation and the use of drugs, and the first discovery of the correlation between 11dhTxB2 and 11dh23dinorTxB2 in urine provides a new possibilitie for the diagnostic and prognostic of cardiovascular diseases.

Impacto de la función renal en el valor pronóstico del metabolismo mineral en pacientes con cardiopatía isquémica crónica / Impact of renal function on the prognostic value of mineral metabolism in patients with chronic ischaemic heart disease patients with chronic ischaemic heart disease

INTRODUCCION: La parathormona (PTH) es un componente del metabolismo mineral (MM) que ha demostrado aportar valor pronóstico en los pacientes con cardiopatía isquémica crónica (CIC) y función renal preservada. Sin embargo, la influencia de la función renal en el papel pronóstico de la PTH en los pacientes con CIC aún no se ha demostrado.ObjetivoEvaluar la influencia del filtrado glomerular renal estimado (FGRe) sobre el papel pronóstico de la PTH y otros marcadores del MM en los pacientes con CIC. MÉTODOS: Analizamos el valor pronóstico de distintos componentes del MM (PTH, klotho, fósforo, calcidiol y factor de crecimiento de fibroblastos-23 [FGF23]) en 964 pacientes con CIC incluidos en 5 hospitales de Madrid en función de si presentaban FGRe <60ml/min/1,73m2 (LFGR) o FGRe≥60ml/min/1,73m2 (HFGR). El objetivo primario fue la combinación de muerte con eventos isquémicos (cualquier síndrome coronario agudo, accidente cerebrovascular isquémico o accidente isquémico transitorio). El FGR se calculó mediante el método Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). RESULTADOS: La edad era de 60,0 (52,0-72,0) años y el 76,2% de los casos eran varones, con una mediana del FGRe de 80,4 (65,3-93,1)ml/min/1,73m2. El seguimiento fue de 5,39 (2,81-6,92) años. Setecientos noventa pacientes presentaron HGFR y 174 LGFR. En pacientes con HFGR, los predictores del endpoint combinado fueron los niveles plasmáticos de calcidiol (HR=0,023 [0,94-0,99], p=0,023); FGF23 (HR=1,00 [1,00-1,003], p=0,036); colesterol no-HDL (HR=1,01 [1,00-1,01], p=0,026) y troponina de alta sensibilidad (HR=5,12 [1,67-15,59], p=0,004), junto con la edad (HR=1,03 [1,01-1,05], p=0,01), el tratamiento con estatinas (HR=0,36 [0,19-0,68], p=0,002); nitratos (HR=1,13 [1,07-2,79], p=0,027); dihidropiridinas (HR=1,71 [1,05-2,77], p=0,032); verapamilo (HR=5,71 [1,35-24,1], p=0,018) e inhibidores de la bomba de protones (HR=2,23 [1,36-3,68], p=0,002). [...]

BACKGROUND: Parathormone (PTH) is a component of the Mineral Metabolism (MM) system that has been shown recently to add prognostic value in pts. with stable coronary artery disease (SCAD) and average renal function. However, the influence of renal function on the prognostic role of PTH in pts. with SCAD has not been shown yet.PurposeTo assess the influence of estimated glomerular filtration rate (eGFR) on the prognostic role of PTH and other MM markers in pts. with SCAD. METHODS: We analyzed the prognostic value of MM markers (PTH, klotho, phosphate, calcidiol [25-hydroxyvitamin D], and fibroblast growth factor-23 [FGF23]) in 964 pts. with SCAD and eGFR<60ml/min/1.73 m2 (LGFR) vs pts. with eGFR≥60ml/min/1.73 m2 (HGFR) included in five hospitals of Madrid. The main outcome was the combination of death with ischemic events (any acute coronary syndrome, ischemic stroke or transient ischemic attack). eGFR was calculated by the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). RESULTS: Age was 60.0 (52.0-72.0) years, 76.2% of patients were men, and eGFR was 80.4 (65.3-93.1) ml/min/1,73 m2. Median follow-up was 5.39 (2.81-6.92) years. There were 790 pts. with HGFR and 174 with LGFR. In HGFR pts., predictors of ischemic events or death were plasma levels of calcidiol [HR=0.023 (0.94-0.99) p=0.023], FGF23 [HR=1.00 (1.00-1.003) p=0.036], non-HDL cholesterol [HR=1.01 (1.00-1.01) p=0.026] and high sensitivity troponin I [HR=5.12 (1.67-15.59) p=0.004], along with age [HR=1.03 (1.01-1.05) p=0.01], treatment with statins [HR=0.36 (0.19-0.68) p=0.002], nitrates [HR=1.13 (1.07-2.79) p=0.027], dihydropyridines [HR=1.71 (1.05-2.77) p=0.032], verapamil [HR=5.71 (1.35-24.1) p=0.018], and proton-pump inhibitors [HR=2.23 (1.36-3.68) p= 0.002]. [...]

Increased Collagen Turnover Is a Feature of Fibromuscular Dysplasia and Associated With Hypertrophic Radial Remodeling: A Pilot, Urine Proteomic Study.

Fibromuscular dysplasia (FMD), a nonatherosclerotic, noninflammatory disease of medium-sized arteries, is an underdiagnosed disease. We investigated the urinary proteome and developed a classifier for discrimination of FMD from healthy controls and other diseases. We further hypothesized that urinary proteomics biomarkers may be associated with alterations in medium-sized, but not large artery geometry and mechanics. The study included 33 patients with mostly multifocal, renal FMD who underwent in depth arterial exploration using ultra-high frequency ultrasound. The cohort was separated in a training set of 23 patients with FMD from Belgium and an independent test set of 10 patients with FMD from Italy. For each set, controls matched 2:1 were selected from the Human Urinary Proteome Database. The specificity of the classifier was tested in 700 additional controls from general population studies, patients with chronic kidney disease (n=66) and coronary artery disease (n=31). Three hundred thirty-five urinary peptides, mostly related to collagen turnover, were identified in the training cohort and combined into a classifier. When applying in the test cohort, the area under the receiver operating characteristic curve was 1.00, 100% specificity at 100% sensitivity. The classifier maintained a high specificity in additional controls (98.3%), patients with chronic kidney (90.9%) and coronary artery (96.8%) diseases. Furthermore, in patients with FMD, the proteomic score was positively associated with radial wall thickness and wall cross-sectional area. In conclusion, a proteomic score has the potential to discriminate between patients with FMD and controls. If confirmed in a wider and more diverse cohort, these findings may pave the way for a noninvasive diagnostic test of FMD.

Toxic Metals and Subclinical Atherosclerosis in Carotid, Femoral, and Coronary Vascular Territories: The Aragon Workers Health Study.

OBJECTIVE: Studies evaluating the association of metals with subclinical atherosclerosis are mostly limited to carotid arteries. We assessed individual and joint associations of nonessential metals exposure with subclinical atherosclerosis in 3 vascular territories. Approach and Results: One thousand eight hundred seventy-three Aragon Workers Health Study participants had urinary determinations of inorganic arsenic species, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten. Plaque presence in carotid and femoral arteries was determined by ultrasound. Coronary Agatston calcium score ≥1 was determined by computed tomography scan. Median arsenic, barium, cadmium, chromium, antimony, titanium, uranium, vanadium, and tungsten levels were 1.83, 1.98, 0.27, 1.18, 0.05, 9.8, 0.03, 0.66, and 0.23 µg/g creatinine, respectively. The adjusted odds ratio (95% CI) for subclinical atherosclerosis presence in at least one territory was 1.25 (1.03-1.51) for arsenic, 1.67 (1.22-2.29) for cadmium, and 1.26 (1.04-1.52) for titanium. These associations were driven by arsenic and cadmium in carotid, cadmium and titanium in femoral, and titanium in coronary territories and mostly remained after additional adjustment for the other relevant metals. Titanium, cadmium, and antimony also showed positive associations with alternative definitions of increased coronary calcium. Bayesian Kernel Machine Regression analysis simultaneously evaluating metal associations suggested an interaction between arsenic and the joint cadmium-titanium exposure. CONCLUSIONS: Our results support arsenic and cadmium and identify titanium and potentially antimony as atherosclerosis risk factors. Exposure reduction and mitigation interventions of these metals may decrease cardiovascular risk in individuals without clinical disease.

Effect of 1,5-anhydroglucitol levels on culprit plaque rupture in diabetic patients with acute coronary syndrome.

BACKGROUND: Postprandial hyperglycemia was reported to play a key role in established risk factors of coronary artery diseases (CAD) and cardiovascular events. Serum 1,5-anhydroglucitol (1,5-AG) levels are known to be a clinical marker of short-term postprandial glucose (PPG) excursions. Low serum 1,5-AG levels have been associated with occurrence of CAD. However, the relationship between 1,5-AG levels and coronary plaque rupture has not been fully elucidated. The aim of this study was to evaluate 1,5-AG as a predictor of coronary plaque rupture in diabetic patients with acute coronary syndrome (ACS). METHODS: A total of 144 diabetic patients with ACS were included in this study. All patients underwent intravascular ultrasound examination, which revealed 49 patients with plaque rupture and 95 patients without plaque rupture in the culprit lesion. Fasting blood glucose (FBG), hemoglobin A1c (HbA1c) and 1,5-AG levels were measured before coronary angiography. Fasting urinary 8-iso-prostaglandin F2α (8-iso-PGF2α) level was measured and corrected by creatinine clearance. RESULTS: Patients with ruptured plaque had significantly lower serum 1,5-AG levels, longer duration of diabetes, higher HbA1c and FBG levels than patients without ruptured plaque in our study population. In multivariate analysis, low 1,5-AG levels were an independent predictor of plaque rupture (odds ratio 3.421; P = 0.005) in diabetic patients with ACS. The area under the receiver-operating characteristic curve for 1,5-AG (0.658, P = 0.002) to predict plaque rupture was superior to that for HbA1c (0.587, P = 0.087). Levels of 1,5-AG were significantly correlated with urinary 8-iso-prostaglandin F2α levels (r = - 0.234, P = 0.005). CONCLUSIONS: Serum 1,5-AG may identify high risk for coronary plaque rupture in diabetic patients with ACS, which suggests PPG excursions are related to the pathogenesis of plaque rupture in diabetes.

microRNA-155 Is Decreased During Atherosclerosis Regression and Is Increased in Urinary Extracellular Vesicles During Atherosclerosis Progression.

Background: Atherosclerosis is a chronic inflammatory disease driven by macrophage accumulation in medium and large sized arteries. Macrophage polarization and inflammation are governed by microRNAs (miR) that regulate the expression of inflammatory proteins and cholesterol trafficking. Previous transcriptomic analysis led us to hypothesize that miR-155-5p (miR-155) is regulated by conjugated linoleic acid (CLA), a pro-resolving mediator which induces regression of atherosclerosis in vivo. In parallel, as extracellular vesicles (EVs) and their miR content have potential as biomarkers, we investigated alterations in urinary-derived EVs (uEVs) during the progression of human coronary artery disease (CAD). Methods: miR-155 expression was quantified in aortae from ApoE-/- mice fed a 1% cholesterol diet supplemented with CLA blend (80:20, cis-9,trans-11:trans-10,cis-12 respectively) which had been previously been shown to induce atherosclerosis regression. In parallel, human polarized THP-1 macrophages were used to investigate the effects of CLA blend on miR-155 expression. A miR-155 mimic was used to investigate its inflammatory effects on macrophages and on ex vivo human carotid endarterectomy (CEA) plaque specimens (n = 5). Surface marker expression and miR content were analyzed in urinary extracellular vesicles (uEVs) obtained from patients diagnosed with unstable (n = 12) and stable (n = 12) CAD. Results: Here, we report that the 1% cholesterol diet increased miR-155 expression while CLA blend supplementation decreased miR-155 expression in the aorta during atherosclerosis regression in vivo. CLA blend also decreased miR-155 expression in vitro in human THP-1 polarized macrophages. Furthermore, in THP-1 macrophages, miR-155 mimic decreased the anti-inflammatory signaling proteins, BCL-6 and phosphorylated-STAT-3. In addition, miR-155 mimic downregulated BCL-6 in CEA plaque specimens. uEVs from patients with unstable CAD had increased expression of miR-155 in comparison to patients with stable CAD. While the overall concentration of uEVs was decreased in patients with unstable CAD, levels of CD45+ uEVs were increased. Additionally, patients with unstable CAD had increased CD11b+ uEVs and decreased CD16+ uEVs. Conclusion: miR-155 suppresses anti-inflammatory signaling in macrophages, is decreased during regression of atherosclerosis in vivo and is increased in uEVs from patients with unstable CAD suggesting miR-155 has potential as a prognostic indicator and a therapeutic target.

Increased urinary adiponectin level is associated with contrast-induced nephropathy in patients undergoing elective percutaneous coronary intervention.

BACKGROUND: Contrast-induced nephropathy (CIN) is one of major and serious complications in patients undergoing percutaneous coronary intervention (PCI). It is unknown whether increased urinary adiponectin (UAPN), a sensitive marker for early renal function impairment, is associated with an increased risk of CIN. Therefore, we prospectively investigate the association of UAPN with CIN. METHODS: We prospectively enrolled 208 patients who were undergoing elective PCI. The baseline UAPN was assessed prior to PCI. The ROC analysis was used to evaluate the predictive value of UAPN for CIN. Multivariate logistic regression analysis was performed to analyze the independent risk factors for CIN. RESULTS: Of 208 patients, CIN occurred in 19 patients (9.13%), and 6 of them (2.88%) required dialysis. Patients with CIN had a higher UAPN level than those without CIN (17.15 ± 12.36 vs. 10.29 ± 3.04 ng/ml, P < 0.01). ROC analysis showed that the optimal cutoff value of UAPN for predicting CIN was 12.24 ng/ml with 68.42% sensitivity and 76.72% specificity (AUC = 0.7204; 95% CI, 0.582-0.859; 푃< 0.01). Multivariate analysis demonstrated that UAPN (OR, 5.071; 95% CI,1.711-15.028; P < 0.01) and serum creatinine (Scr) > 124 µmol/L (OR, 4.210; 95% CI, 1.297-13.669; P < 0.01) were independently associated with CIN. CONCLUSIONS: Our present study showed that a higher baseline UAPN (≥12.24 ng/ml) level was significantly associated with an increased risk for developing CIN post PCI.

Metabolomics profiling and pathway analysis of human plasma and urine reveal further insights into the multifactorial nature of coronary artery disease.

BACKGROUND: Coronary artery disease (CAD) claims lives yearly. Nuclear magnetic resonance (1H NMR) metabolomics analysis is efficient in identifying metabolic biomarkers which lend credence to diagnosis. We aimed to identify CAD metabotypes and its implicated pathways using 1H NMR analysis. METHODS: We analysed plasma and urine samples of 50 stable CAD patients and 50 healthy controls using 1H NMR. Orthogonal partial least square discriminant analysis (OPLS-DA) followed by multivariate logistic regression (MVLR) models were developed to indicate the discriminating metabotypes. Metabolic pathway analysis was performed to identify the implicated pathways. RESULTS: Both plasma and urine OPLS-DA models had specificity, sensitivity and accuracy of 100%, 96% and 98%, respectively. Plasma MVLR model had specificity, sensitivity, accuracy and AUROC of 92%, 86%, 89% and 0.96, respectively. The MVLR model of urine had specificity, sensitivity, accuracy and AUROC of 90%, 80%, 85% and 0.92, respectively. 35 and 12 metabolites were identified in plasma and urine metabotypes, respectively. Metabolic pathway analysis revealed that urea cycle, aminoacyl-tRNA biosynthesis and synthesis and degradation of ketone bodies pathways were significantly disturbed in plasma, while methylhistidine metabolism and galactose metabolism pathways were significantly disturbed in urine. The enrichment over representation analysis against SNPs-associated-metabolite sets library revealed that 85 SNPs were significantly enriched in plasma metabotype. CONCLUSIONS: Cardiometabolic diseases, dysbiotic gut-microbiota and genetic variabilities are largely implicated in the pathogenesis of CAD.

Differential urinary proteins to diagnose coronary heart disease based on iTRAQ quantitative proteomics.

Coronary artery disease (CAD) is a manifestation of systemic atherosclerotic disease. It is assessed by intervention or traditional scoring risk factors. Diagnosis is limited by inaccurate and invasive methods. Developing noninvasive methods to screen for the risk of CAD is a major challenge. We aimed to identify urinary proteins associated with CAD. We utilized iTRAQ labeling followed by 2D LC-MS/MS to compare the urinary proteome of CAD patients to healthy cohorts. The multiple reaction monitoring (MRM) was used to verify the differential proteins. ROC analysis based on MRM data was used to evaluate the diagnostic application. A total of 876 proteins were quantified, and 100 differential proteins were found. Functional analysis revealed that the differential proteins were mainly associated with Liver X Receptor/Retinoid X Receptor (LXR/RXR) pathway activation, atherosclerosis signaling, production of nitric oxide and reactive oxygen species, and the top upstream regulator of the differential proteins by IPA analysis indicated to the APOE. Nineteen differential proteins were verified by MRM analysis. ROC based on MRM data revealed that the combination of two proteins (APOD and TFF1) could diagnose CAD with 85% sensitivity and 99% specificity (AUC 0.95). The urinary proteome might reflect the pathophysiological changes in CAD and be used for the clinical study of CAD.

Urinary excretion of homocysteine thiolactone and the risk of acute myocardial infarction in coronary artery disease patients: the WENBIT trial.

OBJECTIVES: No individual homocysteine (Hcy) metabolite has been studied as a risk marker for coronary artery disease (CAD). Our objective was to examine Hcy-thiolactone, a chemically reactive metabolite generated by methionyl-tRNA synthetase and cleared by the kidney, as a risk predictor of incident acute myocardial infarction (AMI) in the Western Norway B-Vitamin Intervention Trial. DESIGN: Single centre, prospective double-blind clinical intervention study, randomized in a 2 × 2 factorial design. SUBJECTS AND METHODS: Patients with suspected CAD (n = 2049, 69.8% men; 61.2-year-old) were randomized to groups receiving daily (i) folic acid (0.8 mg)/vitamin B12 (0.4 mg)/vitamin B6 (40 mg); (ii) folic acid/vitamin B12 ; (iii) vitamin B6 or (iv) placebo. Urinary Hcy-thiolactone was quantified at baseline, 12 and 38 months. RESULTS: Baseline urinary Hcy-thiolactone/creatinine was significantly associated with plasma tHcy, ApoA1, glomerular filtration rate, potassium and pyridoxal 5'-phosphate (positively) and with age, hypertension, smoking, urinary creatinine, plasma bilirubin and kynurenine (negatively). During median 4.7-years, 183 patients (8.9%) suffered an AMI. In Cox regression analysis, Hcy-thiolactone/creatinine was associated with AMI risk (hazard ratio = 1.58, 95% confidence interval = 1.10-2.26, P = 0.012 for trend; adjusted for age, gender, tHcy). This association was confined to patients with pyridoxic acid below median (adjusted HR = 2.72, 95% CI = 1.47-5.03, P = 0.0001; Pinteraction = 0.020). B-vitamin/folate treatments did not affect Hcy-thiolactone/creatinine and its AMI risk association. CONCLUSIONS: Hcy-thiolactone/creatinine ratio is a novel AMI risk predictor in patients with suspected CAD, independent of traditional risk factors and tHcy, but modified by vitamin B6 catabolism. These findings lend a support to the hypothesis that Hcy-thiolactone is mechanistically involved in cardiovascular disease.

Urinary 8-iso-prostaglandin F2α as a risk marker for the vulnerability of culprit plaque in diabetic patients with stable coronary artery disease.

We evaluated the association of urinary excretion of 8-iso-prostaglandin F2α (8-iso-PGF2α) with the vulnerability of culprit lesions in 156 age- and sex-matched diabetic stable coronary artery disease (CAD) patients with or without thin-capped fibroatheroma (TCFA) identified by iMAP intravascular ultrasound. Fasting urinary 8-iso-PGF2α level was measured and corrected by creatinine clearance. Compared to non-TCFA group, patients with TCFA had higher urinary 8-iso-PGF2α levels [114.6 (71.1, 181.5) vs. 83.0 (63.2, 138.2) pmol/mmolCr, P = 0.012]. Urinary 8-iso-PGF2α level was positively correlated with percent necrotic volume of culprit lesion (r = 0.218, P = 0.006). High urinary 8-iso-PGF2α level (OR 2.941, P = 0.009) was independently associated with the presence of TCFA and displayed a significant value in predicting TCFA plaques in study patients. The current study indicated that urinary 8-iso-PGF2α may be an important surrogate marker for the vulnerability of culprit lesion in diabetic patients with CAD.

Association between elevated urinary levels of kidney injury molecule type 1 and adverse cardiovascular events at 12 months in patients with coronary artery disease.

INTRODUCTION Contrast­induced nephropathy is associated with worse prognosis in patients with coronary artery disease (CAD); however, the prognostic role of urinary biomarkers of renal injury has not been fully established. OBJECTIVES We evaluated the clinical utility of urinary biomarkers for the prediction of major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing coronary angiography. PATIENTS AND METHODS This prospective study included 95 consecutive patients with stable and unstable CAD (men, 69.5%; median age, 65 years), referred for coronary angiography and monitored for MACCEs during 12-month follow-up. MACCEs were defined as cardiovascular death, myocardial infarction, myocardial revascularization, or stroke. Urine samples were collected 24 hours before and 6 hours after coronary angiography and assayed for kidney injury molecule type 1 (KIM-1), interleukin 18, liver fatty acid-binding protein, and renalase, using an enzyme-linked immunosorbent assay. The results were adjusted for urinary creatinine concentration. RESULTS MACCEs occurred in 10 patients (10.5%). These patients had a higher rate of postprocedural contrast­induced acute kidney injury than patients without MACCEs (30.0% vs 7.1%, P = 0.02), higher median SYNTAX score (25.5 points vs 11.5 points, P = 0.04), higher postprocedural KIM­1 concentrations (0.45 ng/mg vs 0.21 ng/mg, P = 0.03), and a larger absolute increase of urinary KIM­1 levels (ΔKIM­1; 0.41 ng/mg vs 0.10 ng/mg, P = 0.01). Preprocedural values of KI M­­1 and other biomarkers were comparable between groups. Patients with ΔKIM­1 levels above the 75th percentile had worse 12­month prognosis (P = 0.0004). ΔKIM­1 levels were an independent predictor of 12­month MACCEs (P = 0.001). MACCEs were accurately predicted by ΔKIM­1 levels exceeding 0.093 ng/mg (area under the curve, 0.752; P = 0.0001). CONCLUSIONS Excessive increase of urinary KIM­1 levels after coronary angiography may help identify CAD patients with poor 12­month prognosis.

Results, meta-analysis and a first evaluation of UNOxR, the urinary nitrate-to-nitrite molar ratio, as a measure of nitrite reabsorption in experimental and clinical settings.

We recently found that renal carbonic anhydrase (CA) is involved in the reabsorption of inorganic nitrite (NO2-), an abundant reservoir of nitric oxide (NO) in tissues and cells. Impaired NO synthesis in the endothelium and decreased NO bioavailability in the circulation are considered major contributors to the development and progression of renal and cardiovascular diseases in different conditions including diabetes. Isolated human and bovine erythrocytic CAII and CAIV can convert nitrite to nitrous acid (HONO) and its anhydride N2O3 which, in the presence of thiols (RSH), are further converted to S-nitrosothiols (RSNO) and NO. Thus, CA may be responsible both for the homeostasis of nitrite and for its bioactivation to RSNO/NO. We hypothesized that enhanced excretion of nitrite in the urine may contribute to NO-related dysfunctions in the renal and cardiovascular systems, and proposed the urinary nitrate-to-nitrite molar ratio, i.e., UNOxR, as a measure of renal CA-dependent excretion of nitrite. Based on results from clinical and experimental animal studies, here, we report on a first evaluation of UNOxR. We determined UNOxR values in preterm neonates, healthy children, and adults, in children suffering from type 1 diabetes mellitus (T1DM) or Duchenne muscular dystrophy (DMD), in elderly subjects suffering from chronic rheumatic diseases, type 2 diabetes mellitus (T2DM), coronary artery disease (CAD), or peripheral arterial occlusive disease (PAOD). We also determined UNOxR values in healthy young men who ingested isosorbide dinitrate (ISDN), pentaerythrityl tetranitrate (PETN), or inorganic nitrate. In addition, we tested the utility of UNOxR in two animal models, i.e., the LEW.1AR1-iddm rat, an animal model of human T1DM, and the APOE*3-Leiden.CETP mice, a model of human dyslipidemia. Mean UNOxR values were lower in adult patients with rheumatic diseases (187) and in T2DM patients of the DALI study (74) as compared to healthy elderly adults (660) and healthy young men (1500). The intra- and inter-variabilities of UNOxR were of the order of 50% in young and elderly healthy subjects. UNOxR values were lower in black compared to white boys (314 vs. 483, P = 0.007), which is in line with reported lower NO bioavailability in black ethnicity. Mean UNOxR values were lower in DMD (424) compared to healthy (730) children, but they were higher in T1DM children (1192). ISDN (3 × 30 mg) decreased stronger UNOxR compared to PETN (3 × 80 mg) after 1 day (P = 0.046) and after 5 days (P = 0.0016) of oral administration of therapeutically equivalent doses. In healthy young men who ingested NaNO3 (0.1 mmol/kg/d), UNOxR was higher than in those who ingested the same dose of NaCl (1709 vs. 369). In LEW.1AR1-iddm rats, mean UNOxR values were lower than in healthy rats (198 vs. 308) and comparable to those in APOE*3-Leiden.CETP mice (151).

Urine Cotinine level with smoking history predicts a risk of coronary artery calcification.

We investigated whether urine cotinine level, alone or combined with smoking status and cumulative smoking amount, could predict coronary calcium (CAC) score increase over time. The study population included 10,980 subjects. We analysed an association between CAC score increase over time and single or combined smoking-related factors. Urine cotinine level of ≥100 ng/mL, current or ex-smokers, and cumulative smoking amount of ≥1 pack-years (PY) showed significantly higher odds ratios (ORs) for CAC score increase over time. A combination of current smokers with >10 PY and urine cotinine level of ≥100 ng/mL showed the highest OR. Irrespective of smoking status and cumulative smoking amount, all combinations with urine cotinine of ≥100 ng/mL showed higher ORs than other combinations with urine cotinine level of <100 ng/mL. Urine cotinine levels can be useful to predict coronary artery calcification and encourage smokers to quit smoking.

Urinary renalase concentration in patients with preserved kidney function undergoing coronary angiography.

AIM: The purpose of the study was to evaluate urinary renalase concentration before and after coronary angiography/percutaneous coronary interventions (CA/PCI) in patients with coronary artery disease (CAD) and preserved kidney function and verify its potential application as contrast-induced acute kidney injury (CI-AKI) diagnostic marker. METHODS: This prospective study comprised 95 consecutive patients (69.5% men; median age 65 years) with CAD submitted to elective or urgent CA/PCI. Data regarding 128 clinical variables were obtained. Urine samples were collected on admission and 6 h after CA/PCI and tested for urinary renalase using ELISA method, which was expressed as renalase-to-creatinine ratio. The CI-AKI diagnosis was based on ≥50% relative or ≥0.3 mg/dl absolute increase of serum creatinine concentration 48 h following the procedure. RESULTS: Nine patients developed CI-AKI (9.5%). In comparison to baseline values, urinary renalase-to-creatinine ratio significantly decreased 6 h following CA/PCI, (2843.6 vs.1540.7 ng/mg, P < 0.0001). Nine patients developed CI-AKI (9.5%).The reduction of renalase level was profound both in CI-AKI (2709.7 vs. 1585.7 ng/mg, P = 0.007) and non-CI-AKI group (2814.9 vs.1561.8 ng/mg, P < 0.0001). There was a trend towards a greater relative decrease of urinary renalase in CI-AKI group (-57.3 vs.-41.8%, P = 0.10). Univariate analysis revealed that both pre- and post-procedural urinary renalase did not predict CI-AKI onset; however, absolute decrease of renalase below 25 percentile was a predictor of CI-AKI (OR = 5.4, 95% CI:1.3-21.9, P = 0.027). CONCLUSION: Urinary renalase concentration is reduced in the aftermath of CA/PCI, which may be related to CI-AKI development. Further studies are warranted to elucidate the role of urinary renalase as a CI-AKI diagnostic marker.

Leukotriene biosynthesis in coronary artery disease. Results of the Leukotrienes and Thromboxane In Myocardial Infarction (LTIMI) study.

INTRODUCTION Leukotrienes (LTs) may be involved in atherosclerosis and may contribute to cardiovascular outcomes in CAD. OBJECTIVES    We aimed to compare the baseline LT production in patients with stable CAD (sCAD) and myocardial infarction (MI), and to assess whether an increased LT production is associated with major adverse cardiovascular events (MACEs) at 1 year after MI. PATIENTS AND METHODS    LTIMI (Leukotrienes and Thromboxane In Myocardial Infarction) was a single­center, prospective, observational study of patients with stable sCAD and MI. Urinary leukotriene E4 (LTE4) levels were measured on admission, at 1 month, and at 1 year, using high­performance liquid chromatography tandem mass spectrometry. RESULTS    Of the 404 patients screened, 289 were enrolled (110 with sCAD and 179 with MI; mean [SD] age, 63.9 [10.9] years). Patients with MI had higher median (interquartile range [IQR]) levels of log­transformed LTE4 (logLTE4) than those with sCAD (4.74 pg/mg creatinine [4-5.45] vs 4.51 pg/mg creatinine [3.99 4.86], respectively; P <0.001). Median (IQR) logLTE4 levels in patients with MI significantly decreased at 1 month to 4.37 pg/mg creatinine (3.81-4.95), and at 1 year to 4.16 pg/mg creatinine (3.55-4.85). The baseline urinary logLTE4 levels were similar in patients with MACEs and those without MACEs (median [IQR], 4.78 pg/mg creatinine [4.01-5.56]) and 4.68 pg/mg creatinine [3.97-5.28], respectively; P >0.05). Multiple regression showed no relation between LTE4 levels and the incidence of MACEs. CONCLUSIONS    LT production assessed by urinary LTE4 excretion is higher in patients with MI than in those with sCAD; however, LTE4 levels at baseline do not differ between patients with and without MACEs at 1 year after MI.

Prognostic value of urinary 11-dehydro-thromboxane B2 for mortality: A cohort study of stable coronary artery disease patients treated with aspirin.

AIM: There is a variable cardiovascular risk reduction attributable to aspirin because of individual differences in the suppression of thromboxane A2 and its downstream metabolite 11-dehydro-thromboxane B2 (11dhTxB2 ). The aim of this study is to evaluate the optimal cut point of urinary 11dhTxB2 for the risk of mortality in aspirin-treated coronary artery disease (CAD) patients. METHODS AND RESULTS: This was a prospective cohort study including stable CAD patients who visited the Baylor Heart and Vascular Hospital in Dallas or the Texas Heart Hospital Baylor Plano, TX between 2010 and 2013. The outcome of all-cause mortality was ascertained from chart review and automated sources. The 449 patients included in this analysis had a mean age of 66.1 ± 10.1 years. 67 (14.9%) patients died within 5 years; 56 (87.5%) of the 64 patients with known cause of death suffered a cardiovascular related mortality. Baseline ln(urinary 11dhTxB2 /creatinine) ranged between 5.8 and 11.1 (median = 7.2) with the higher concentrations among those who died (median: 7.6) than those who survived (median = 7.2, P < 0.001). Using baseline ln(11dhTxB2 ) to predict all-cause mortality, the area under the curve was 0.70 (95% CI: 0.64-0.76). The optimal cut point was found to be ln(7.38) = 1597.8 pg/mg, which had the following decision statistics: sensitivity = 0.67, specificity = 0.62, positive predictive value = 0.24, negative predictive value = 0.92, and accuracy = 0.63. CONCLUSION: Our data indicate the optimal cut point for urine 11dhTxB2 is 1597.8 (pg/mg) for the risk prediction of mortality over five years in stable patients with CAD patients treated with aspirin.

1H NMR based pharmacometabolomics analysis of urine identifies metabolic phenotype of clopidogrel high on treatment platelets reactivity in coronary artery disease patients.

Clopidogrel high on treatment platelets reactivity (HTPR) has burdened achieving optimum therapeutic outcome. Although there are known genetic and non-genetic factors associated with clopidogrel HTPR, which explain in part clopidogrel HTPR, yet, great portion remains unknown, often hindering personalizing antiplatelet therapy. Nuclear magnetic resonance (1H NMR) pharmacometabolomics analysis is useful technique to phenotype drug response. We investigated using 1H NMR analysis to phenotype clopidogrel HTPR in urine. Urine samples were collected from 71 coronary artery disease (CAD) patients who were planned for interventional angiographic procedure prior to taking 600mg clopidogrel loading dose (LD) and 6h post LD. Patients' platelets function testing was assessed with the VerifyNow® P2Y12 assay at 6h after LD. Urine samples were analysed using 1H NMR. Multivariate statistical analysis was used to identify metabolites associated with clopidogrel HTPR. In pre-dose samples, 16 metabolites were associated with clopidogrel HTPR. However, 18 metabolites were associated with clopidogrel HTPR in post-dose samples. The pathway analysis of the identified biomarkers reflected that multifactorial conditions are associated with clopidogrel HTPR. It also revealed the implicated role of gut microbiota in clopidogrel HTPR. Pharmacometabolomics not only discovered novel biomarkers of clopidogrel HTPR but also revealed implicated pathways and conditions.