ABSTRACT
Early diagnosis and treatment of chronic kidney disease (CKD) is a worldwide challenge. Subjects with albumin-to-creatinine ratio (ACR) ≥ 30 mg/g and preserved renal function are considered to be at no cardiorenal risk in clinical practice, but prospective clinical studies evidence increased risk, even at the high-normal (HN) ACR range (10-30 mg/g), supporting the need to identify other molecular indicators for early assessment of patients at higher risk. Following our previous studies, here we aim to stratify the normoalbuminuria range according to cardiorenal risk and identify the glycoproteins and N-glycosylation sites associated with kidney damage in subclinical CKD. Glycoproteins were analyzed in urine from hypertensive patients within the HN ACR range compared to control group (C; ACR < 10 mg/g) by mass spectrometry. A different cohort was analyzed for confirmation (ELISA) and sex perspective was evaluated. Patients' follow-up for 8 years since basal urine collection revealed higher renal function decline and ACR progression for HN patients. Differential N-glycopeptides and their N -glycosylation sites were also identified, together with their pathogenicity. N-glycosylation may condition pathological protein deregulation, and a panel of 62 glycoproteins evidenced alteration in normoalbuminuric subjects within the HN range. Haptoglobin-related protein, haptoglobin, afamin, transferrin, and immunoglobulin heavy constant gamma 1 (IGHG1) and 2 (IGHG2) showed increased levels in HN patients, pointing to disturbed iron metabolism and tubular reabsorption and supporting the tubule as a target of interest in the early progression of CKD. When analyzed separately, haptoglobin, afamin, transferrin, and IGHG2 remained significant in HN, in both women and men. At the peptide level, 172 N-glycopeptides showed differential abundance in HN patients, and 26 showed high pathogenicity, 10 of them belonging to glycoproteins that do not show variation between HN and C groups. This study highlights the value of glycosylation in subjects not meeting KDIGO criteria for CKD. The identified N-glycopeptides and glycosylation sites showed novel targets, for both the early assessment of individual cardiorenal risk and for intervention aimed at anticipating CKD progression.
Subject(s)
Glycopeptides , Renal Insufficiency, Chronic , Humans , Male , Female , Glycopeptides/urine , Renal Insufficiency, Chronic/urine , Middle Aged , Glycosylation , Aged , Biomarkers/urine , Creatinine/urine , Glycoproteins/urine , Disease Progression , Albuminuria/urine , Risk Factors , Haptoglobins/metabolismABSTRACT
Atherosclerosis is the predominant pathology associated to premature deaths due to cardiovascular disease. However, early intervention based on a personalized diagnosis of cardiovascular risk is very limited. We have previously identified metabolic alterations during atherosclerosis development in a rabbit model and in subjects suffering from an acute coronary syndrome. Here we aim to identify specific metabolic signatures which may set the basis for novel tools aiding cardiovascular risk diagnosis in clinical practice. In a cohort of subjects with programmed coronary artery bypass grafting (CABG), we have performed liquid chromatography and targeted mass spectrometry analysis in urine and plasma. The role of vascular smooth muscle cells from human aorta (HA-VSMCs) was also investigated by analyzing the intra and extracellular metabolites in response to a pro-atherosclerotic stimulus. Statistically significant variation was considered if p value < 0.05 (Mann-Whitney test). Urinary trimethylamine N-oxide (TMAO), arabitol and spermidine showed higher levels in the CVrisk group compared with a control group; while glutamine and pantothenate showed lower levels. The same trend was found for plasma TMAO and glutamine. Plasma choline, acetylcholine and valine were also decreased in CVrisk group, while pyruvate was found increased. In the secretome of HA-VSMCs, TMAO, pantothenate, glycerophosphocholine, glutathion, spermidine and acetylcholine increased after pro-atherosclerotic stimulus, while secreted glutamine decreased. At intracellular level, TMAO, pantothenate and glycerophosphocholine increased with stimulation. Observed metabolic deregulations pointed to an inflammatory response together with a deregulation of oxidative stress counteraction.
ABSTRACT
OBJECTIVE: A continuous association between albuminuria and cardiorenal risk exists further below moderately increased albuminuria ranges. If only based in albumin to creatinine ratio (ACR) higher than 30âmg/g, a significant percentage of individuals may be out of the scope for therapeutic management. Despite epidemiological outcomes, the identification of biochemical changes linked to early albuminuria is underexplored, and normoalbuminuric individuals are usually considered at no risk in clinical practice. Here, we aimed to identify early molecular alterations behind albuminuria development. METHODS: Hypertensive patients under renin-angiotensin system (RAS) suppression were classified as control, (ACRâ<â10âmg/g) or high-normal (ACRâ=â10-30âmg/g). Urinary protein alterations were quantified and confirmed by untargeted and targeted mass spectrometry. Coordinated protein responses with biological significance in albuminuria development were investigated. Immunohistochemistry assays were performed in human kidney and arterial tissue to in situ evaluate the associated damage. RESULTS: A total of 2663 identified proteins reflect inflammation, immune response, ion transport and lipids metabolism (P valueâ≤â0.01). A1AT, VTDB and KNG1 varied in high-normal individuals (P valueâ<â0.05), correlated with ACR and associated with the high-normal condition (odds ratio of 20.76, 6.00 and 7.04 were found, respectively (P valueâ<â0.001)). After 12 months, protein variations persist and aggravate in progressors to moderately increased albuminuria. At tissue level, differential protein expression was found in kidney from individuals with moderately increased albuminuria and atherosclerotic aortas for the three proteins, confirming their capacity to reflect subclinical organ damage. CONCLUSION: Early renal and vascular damage is molecularly evidenced within the normoalbuminuria condition.
Subject(s)
Albuminuria , Hypertension , Humans , Kidney , Renin-Angiotensin System , UrinalysisABSTRACT
Aims: Current cardiovascular (CV) risk prediction algorithms are able to quantify the individual risk of CV disease. However, CV risk in young adults is underestimated due to the high dependency of age in biomarker-based algorithms. Because oxidative stress is associated with CV disease, we sought to examine CV risk stratification in young adults based on oxidative stress to approach the discovery of new markers for early detection of pathology. Results: Young adults were stratified into (i) healthy controls, (ii) subjects with CV risk factors, and (iii) patients with a reported CV event. Plasma samples were analyzed using FASILOX, a novel approach to interrogate the dynamic thiol redox proteome. We also analyzed irreversible oxidation by targeted searches using the Uniprot database. Irreversible oxidation of cysteine (Cys) residues was greater in patients with reported CV events than in healthy subjects. These results also indicate that oxidation is progressive. Moreover, we found that glutathione reductase and glutaredoxin 1 proteins are differentially expressed between groups and are proteins involved in antioxidant response, which is in line with the impaired redox homeostasis in CV disease. Innovation: This study, for the first time, describes the oxidative stress (reversible and irreversible Cys oxidation) implication in human plasma according to CV risk stratification. Conclusion: The identification of redox targets and the quantification of protein and oxidative changes might help to better understand the role of oxidative stress in CV disease, and aid stratification for CV events beyond traditional prognostic and diagnostic markers. Antioxid. Redox Signal. 35, 602-617.
Subject(s)
Cardiovascular Diseases , Cardiovascular Diseases/diagnosis , Cysteine/metabolism , Humans , Oxidation-Reduction , Oxidative Stress/physiology , Proteome/metabolism , Risk FactorsABSTRACT
BACKGROUND: Subclinical atherosclerosis may result in fatal cardiovascular (CV) events, but the underlying mechanisms and molecular players leading to disease are not entirely understood. Thus, novel approaches capable of identifying the factors involved in pathological progression and providing a better understanding of the subjacent mechanisms are needed. Extracellular vesicles (EVs) have been shown to have numerous biological functions, and their metabolome has recently generated interest as a source of novel biomarkers. The metabolic content of the exosomes has been so far unexplored in cardiovascular disease (CVD), and here, we developed an analytical strategy aimed at probing urinary exosomal metabolite content and its association to CV risk. RESULTS: Direct analysis of the exosomes without metabolite extraction was evaluated by high-resolution magic angle spinning (1H HR-MAS). Other two methodologies for the analysis of exosomal metabolites by 1H NMR were set up, based on methanol or organic solvents sequential extraction. The three methods were compared in terms of the number of detected signals and signal to noise ratio (S/N). The methanol method was applied to identify altered metabolites in the urinary exosomes of subjects with programmed coronary artery by-pass grafting (CABG) versus a control group. Target mass spectrometry (MS) was also performed for differential analysis. The clinical performance of exosomal metabolites of interest in CVD was investigated, and the added value of the exosomes compared to urine analysis was evaluated. Based on S/N ratio, simplicity, reproducibility, and quality of the spectrum, the methanol method was chosen for the study in CVD. A cardiometabolic signature composed by 4-aminohippuric acid, N-1-methylnicotinamide, and citric acid was identified in urinary exosomes. Directly in urine, 4-aminohippuric acid and citric acid do not show variation between groups and changes in N-1-methylnicotinamide are less pronounced, proving the added value of exosomes. CONCLUSIONS: We set up a novel methodology to analyze metabolic alterations in urinary exosomes and identified a cardiometabolic signature in these microvesicles. This study constitutes the first evidence of a role for the exosomal metabolism in CVD and demonstrates the possibility to evaluate the urinary exosomal metabolic content by NMR and MS.
Subject(s)
Cardiovascular Diseases/epidemiology , Exosomes/metabolism , Urinalysis/statistics & numerical data , Urine/chemistry , Adult , Aged , Female , Humans , Male , Middle Aged , Risk FactorsABSTRACT
The predictive value of traditional cardiovascular risk estimators is limited, and young and elderly populations are particularly underrepresented. We aimed to investigate the urine metabolome and its association with cardiovascular risk to identify novel markers that might complement current estimators based on age. Urine samples were collected from 234 subjects categorized into three age-grouped cohorts: 30-50 years (cohort I, young), 50-70 years (cohort II, middle-aged), and > 70 years (cohort III, elderly). Each cohort was further classified into three groups: (a) control, (b) individuals with cardiovascular risk factors, and (c) those who had a previous cardiovascular event. Novel urinary metabolites linked to cardiovascular risk were identified by nuclear magnetic resonance in cohort I and then evaluated by target mass spectrometry quantification in all cohorts. A previously identified metabolic fingerprint associated with atherosclerosis was also analyzed and its potential risk estimation investigated in the three aged cohorts. Three different metabolic signatures were identified according to age: 2-hydroxybutyrate, gamma-aminobutyric acid, hypoxanthine, guanidoacetate, oxaloacetate, and serine in young adults; citrate, cyclohexanol, glutamine, lysine, pantothenate, pipecolate, threonine, and tyramine shared by middle-aged and elderly adults; and trimethylamine N-oxide and glucuronate associated with cardiovascular risk in all three cohorts. The urinary metabolome contains a metabolic signature of cardiovascular risk that differs across age groups. These signatures might serve to complement existing algorithms and improve the accuracy of cardiovascular risk prediction for personalized prevention. KEY MESSAGES: ⢠Cardiovascular risk in the young and elderly is underestimated. ⢠The urinary metabolome reflects cardiovascular risk across all age groups. ⢠Six metabolites constitute a metabolic signature of cardiovascular risk in young adults. ⢠Middle-aged and elderly adults share a cardiovascular risk metabolic signature. ⢠TMAO and glucuronate levels reflect cardiovascular risk across all age groups.
Subject(s)
Biomarkers/urine , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/urine , Metabolome , Metabolomics , Adult , Age Factors , Aged , Aged, 80 and over , Cardiovascular Diseases/etiology , Cross-Sectional Studies , Female , Heart Disease Risk Factors , Humans , Male , Mass Spectrometry , Metabolomics/methods , Middle Aged , Nuclear Magnetic Resonance, Biomolecular , Public Health Surveillance , ROC Curve , Risk Assessment , Risk Factors , Young AdultABSTRACT
ANTECEDENTES Y OBJETIVO: La albuminuria es un indicador de daño orgánico subclínico y un marcador de riesgo cardiovascular y de enfermedad renal. Un porcentaje de pacientes hipertensos desarrollan albuminuria a pesar de estar bajo supresión crónica del sistema renina-angiotensina (SRA). Previamente identificamos metabolitos en orina asociados al desarrollo de albuminuria. En este estudio, investigamos alteraciones metabólicas que reflejen distintos niveles dentro de la condición de normoalbuminuria. PACIENTES, MATERIALES Y MÉTODOS: Se analizó la orina de 48 pacientes hipertensos con supresión crónica del SRA. Se clasificaron según el cociente albúmina/creatinina (ACR) en 3 grupos: normoalbuminuria (< 10 mg/g); normal-alta (10-30 mg/g en varones, o 20-40 mg/g en mujeres) y albuminuria moderadamente elevada (microalbuminuria: 30-200 mg/g o 40-300 mg/g, respectivamente). El metaboloma se analizó mediante espectrometría de masas y se realizó un análisis de correlaciones entre los niveles de los metabolitos alterados y ACR. RESULTADOS: Oxalacetato, 3-ureidopropionato, guanidoacetato y malato muestran una variación significativa entre los grupos normo y micro. Además, estos metabolitos son capaces de diferenciar entre los pacientes normo y normal-alta. Igualmente se observó correlación significativa entre el nivel de los metabolitos identificados con el nivel de ACR. Las variaciones observadas señalan una alteración del metabolismo energético ya en pacientes con albuminuria en el rango normal-alta. CONCLUSIONES: Se confirma la asociación del panel molecular constituido por 3-ureidopropionato, oxalacetato, malato y guanidoacetato con distintos niveles de albuminuria. Así mismo, se ha identificado una huella metabólica capaz de mostrar variación dentro de la condición de normoalbuminuria, lo que permite una estratificación molecular más temprana de los pacientes
BACKGROUND AND AIM: Albuminuria is an indicator of sub-clinical organ damage and a marker of cardiovascular risk and renal disease. A percentage of hypertensive patients develop albuminuria despite being under chronic suppression of the renin-angiotensin system (RAS). We previously identified urinary metabolites associated with the development of albuminuria. In this study, we searched for metabolic alterations which reflect different levels within the condition of normoalbuminuria. PATIENTS, MATERIALS AND METHODS: Urine from 48 hypertensive patients under chronic RAS suppression was analysed. They were classified according to the albumin/creatinine ratio (ACR) into 3 groups: Normoalbuminuria (< 10 mg/g); high-normal (10-30 mg/g in men, or 20-40 mg/g in women); and moderately high albuminuria (microalbuminuria, 30-200 mg/g or 40-300 mg/g, respectively). The metabolome was analysed by mass spectrometry and a correlation analysis was performed between altered metabolite levels and ACR. RESULTS: Oxaloacetate, 3-ureidopropionate, guanidoacetate and malate show significant variation between the normo and micro groups. Additionally, these metabolites are able to differentiate between patients in the normo and high-normal range. A significant correlation between metabolites and ACR was found. Observed variations point to alterations in the energy metabolism already in patients with albuminuria in the high-normal range. CONCLUSIONS: The association between the molecular panel consisting of 3-ureidopropionate, oxaloacetate, malate and guanidoacetate and different levels of albuminuria is confirmed. A metabolic fingerprint was also identified showing variations within the condition of normoalbuminuria allowing an earlier molecular stratification of patients
Subject(s)
Humans , Male , Female , Middle Aged , Aged , Hypertension/metabolism , Albuminuria/metabolism , Renin-Angiotensin System , Creatinine/urine , Mass Spectrometry , Biomarkers/urineABSTRACT
Several models are available to calculate the risk of developing cardiovascular complications in mid-life. The estimation of lifetime risk in the long-term remains an unmet clinical need. We previously identified new molecular plasma signatures for cardiovascular risk stratification in a young population (30-50-years old). The aim of the present study was to determine if the specific signature found in young population changes with age. Proteomic analysis was performed in plasma samples obtained from different age groups, middle-age (50-70-years old, n = 63) and elderly (>70-years old, n = 61), which, in turn were classified into 3 subgroups according to cardiovascular risk. Our previous results in a young population clearly showed two different proteomic signatures. Building on these findings, targeted-mass spectrometry and turbidimetry analyses were used to test these signatures in middle-age and elderly populations. This strategy identified three common proteomic signatures between young and adult patients related to cardiovascular stratification, organ damage and risk prediction. Furthermore, receiver operating characteristic analysis revealed the potential value of these novel markers for lifetime risk stratification. Our results provide new insight into altered molecular mechanisms in the pathogenesis of cardiovascular disease and, more importantly, identify novel protein panels that can stratify patients throughout life. SIGNIFICANCE: Our results revealed three common proteomic signatures between young and adult patients related to cardiovascular stratification, organ damage and risk prediction. The results obtained provide a deeper insight into the pathogenesis of CV diseases and allow the identification of novel protein panels to stratify patients according to CV risk throughout life. While current estimators calculate the risk of having a CV event considering age as the most important factor to CV disease, our results represent an alternative to traditional CV risk factors, allowing the stratification of CV risk regardless of the age. Using a combination of traditional markers and established algorithms with these findings as a future preventive strategy, could facilitate an adequate assessment of CV risk.
Subject(s)
Cardiovascular Diseases , Adult , Aged , Biomarkers , Cardiovascular Diseases/diagnosis , Humans , Middle Aged , Plasma , Proteomics , Risk FactorsABSTRACT
BACKGROUND AND AIM: Albuminuria is an indicator of sub-clinical organ damage and a marker of cardiovascular risk and renal disease. A percentage of hypertensive patients develop albuminuria despite being under chronic suppression of the renin-angiotensin system (RAS). We previously identified urinary metabolites associated with the development of albuminuria. In this study, we searched for metabolic alterations which reflect different levels within the condition of normoalbuminuria. PATIENTS, MATERIALS AND METHODS: Urine from 48 hypertensive patients under chronic RAS suppression was analysed. They were classified according to the albumin/creatinine ratio (ACR) into 3groups: Normoalbuminuria (<10mg/g); high-normal (10-30mg/g in men, or 20-40mg/g in women); and moderately high albuminuria (microalbuminuria, 30-200mg/g or 40-300mg/g, respectively). The metabolome was analysed by mass spectrometry and a correlation analysis was performed between altered metabolite levels and ACR. RESULTS: Oxaloacetate, 3-ureidopropionate, guanidoacetate and malate show significant variation between the normo and micro groups. Additionally, these metabolites are able to differentiate between patients in the normo and high-normal range. A significant correlation between metabolites and ACR was found. Observed variations point to alterations in the energy metabolism already in patients with albuminuria in the high-normal range. CONCLUSIONS: The association between the molecular panel consisting of 3-ureidopropionate, oxaloacetate, malate and guanidoacetate and different levels of albuminuria is confirmed. A metabolic fingerprint was also identified showing variations within the condition of normoalbuminuria allowing an earlier molecular stratification of patients.
Subject(s)
Albuminuria/metabolism , Hypertension/metabolism , Metabolome , Aged , Albuminuria/complications , Female , Humans , Hypertension/complications , Hypertension/urine , Male , Middle AgedABSTRACT
Resistant hypertension prevalence is progressively increasing, and prolonged exposure to suboptimal blood pressure control results in higher cardiovascular risk and end-organ damage. Among various antihypertensive agents, spironolactone seems the most effective choice to treat resistant hypertension once triple therapy including a diuretic fails. However success in blood pressure control is not guaranteed, adverse effects are not negligible, and no clinical tools are available to predict patient's response. Complementary to our previous study of resistant hypertension metabolism, here we investigated urinary proteome changes with potential capacity to predict response to spironolactone. Twenty-nine resistant hypertensives were included. A prospective study was conducted and basal urine was collected before spironolactone administration. Patients were classified in responders or nonresponders in terms of blood pressure control. Protein quantitation was performed by liquid chromatography-mass spectrometry; ELISA and target mass spectrometry analysis were performed for confirmation. Among 3310 identified proteins, HP (haptoglobin) and HPR (haptoglobin-related protein) showed the most significant variations, with increased levels in nonresponders compared with responders before drug administration (variation rate, 5.98 and 7.83, respectively). Protein-coordinated responses were also evaluated by functional enrichment analysis, finding oxidative stress, chronic inflammatory response, blood coagulation, complement activation, and regulation of focal adhesions as physiopathological mechanisms in resistant hypertension. In conclusion, protein changes able to predict patients' response to spironolactone in basal urine were here identified for the first time. These data, once further confirmed, will support clinical decisions on patients' management while contributing to optimize the rate of control of resistant hypertensives with spironolactone.
Subject(s)
Antigens, Neoplasm/urine , Blood Pressure/drug effects , Drug Resistance , Haptoglobins/urine , Hypertension/drug therapy , Spironolactone/therapeutic use , Aged , Biomarkers/urine , Female , Humans , Hypertension/physiopathology , Hypertension/urine , Male , Middle Aged , Mineralocorticoid Receptor Antagonists/therapeutic use , Prognosis , Prospective StudiesABSTRACT
BACKGROUND AND AIMS: The predictive value of traditional CV risk calculators is limited. Novel indicators of CVD progression are needed particularly in the young population. The main aim of this study was the identification of a molecular profile with added value to classical CV risk estimation. METHODS: Eighty-one subjects (30-50 years) were classified in 3 groups according to their CV risk: healthy subjects; individuals with CV risk factors; and those who had suffered a previous CV event. The urine proteome was quantitatively analyzed and significantly altered proteins were identified between patients' groups, either related to CV risk or established organ damage. Target-MS and ELISA were used for confirmation in independent patients' cohorts. Systems Biology Analysis (SBA) was carried out to identify functional categories behind CVD. RESULTS: 4309 proteins were identified, 75 of them differentially expressed. ADX, ECP, FETUB, GDF15, GUAD and NOTCH1 compose a fingerprint positively correlating with lifetime risk estimate (LTR QRISK). Best performance ROC curve was obtained when ECP, GDF15 and GUAD were combined (AUCâ¯=â¯0.96). SBA revealed oxidative stress response, dilated cardiomyopathy, signaling by Wnt and proteasome, as main functional processes related to CV risk. CONCLUSIONS: A novel urinary protein signature is shown, which correlates with CV risk estimation in young individuals. Pending further confirmation, this six-protein-panel could help in CV risk assessment.
Subject(s)
Biomarkers/urine , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/prevention & control , Preventive Medicine/methods , Adrenodoxin/urine , Adult , Cardiology , Cardiovascular System , Eosinophil Cationic Protein/urine , Female , Fetuin-B/urine , Growth Differentiation Factor 15/urine , Guanine Deaminase/urine , Humans , Male , Middle Aged , Proteome , Receptor, Notch1/analysis , Risk Assessment , Risk Factors , Systems BiologyABSTRACT
The evaluation of cardiovascular (CV) risk is based on equations derived from epidemiological data in individuals beyond the limits of middle age such as the Framingham and SCORE risk assessments. Lifetime Risk calculator (QRisk®), estimates CV risk throughout a subjects' lifetime, allowing those. A more aggressive and earlier intervention to be identified and offered protection from the consequences of CV and renal disease. The search for molecular profiles in young people that allow a correct stratification of CV risk would be of great interest to adopt preventive therapeutic measures in individuals at high CV risk. To improve the selection of subjects susceptible to intervention with aged between 30-50 years, we have employed a multiple proteomic strategy to search for new markers of early CV disease or reported CV events and to evaluate their relationship with Lifetime Risk. Blood samples from 71 patients were classified into 3 groups according to their CV risk (healthy, with CV risk factors and with a previously reported CV event subjects) and they were analyzed using a high through quantitative proteomics approach. This strategy allowed three different proteomic signatures to be defined, two of which were related to CV stratification and the third one involved markers of organ damage.
Subject(s)
Biomarkers/blood , Cardiovascular Diseases/blood , Cardiovascular Diseases/classification , Cardiovascular System/metabolism , Risk Assessment/methods , Adult , Cardiovascular Diseases/etiology , Female , Humans , Male , Middle Aged , Proteomics , Risk FactorsABSTRACT
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
ABSTRACT
Resistant hypertension (RH) affects 9% to 12% of hypertensive adults. Prolonged exposure to suboptimal blood pressure control results in end-organ damage and cardiovascular risk. Spironolactone is the most effective drug for treatment, but not all patients respond and side effects are not negligible. Little is known on the mechanisms responsible for RH. We aimed to identify metabolic alterations in urine. In addition, a potential capacity of metabolites to predict response to spironolactone was investigated. Urine was collected from 29 patients with RH and from a group of 13 subjects with pseudo-RH. For patients, samples were collected before and after spironolactone administration and were classified in responders (n=19) and nonresponders (n=10). Nuclear magnetic resonance was applied to identify altered metabolites and pathways. Metabolites were confirmed by liquid chromatography-mass spectrometry. Citric acid cycle was the pathway most significantly altered (P<0.0001). Metabolic concentrations were quantified and ranged from ng/mL malate to µg/mL citrate. Citrate and oxaloacetate increased in RH versus pseudoresistant. Together with α-ketoglutarate and malate, they were able to discriminate between responders and nonresponders, being the 4 metabolites increased in nonresponders. Combined as a prediction panel, they showed receiver operating characteristiccurve with area under the curve of 0.96. We show that citric acid cycle and deregulation of reactive oxygen species homeostasis control continue its activation after hypertension was developed. A metabolic panel showing alteration before spironolactone treatment and predicting future response of patients is shown. These molecular indicators will contribute optimizing the rate of control of RH patients with spironolactone.
Subject(s)
Citric Acid , Drug Resistance/physiology , Drug-Related Side Effects and Adverse Reactions , Hypertension , Spironolactone , Aged , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/adverse effects , Antihypertensive Agents/pharmacokinetics , Chromatography, Liquid/methods , Citric Acid/analysis , Citric Acid/metabolism , Drug-Related Side Effects and Adverse Reactions/diagnosis , Drug-Related Side Effects and Adverse Reactions/urine , Female , Humans , Hypertension/drug therapy , Hypertension/epidemiology , Hypertension/metabolism , Ketoglutaric Acids/analysis , Ketoglutaric Acids/metabolism , Male , Middle Aged , Predictive Value of Tests , Prognosis , Spain/epidemiology , Spironolactone/administration & dosage , Spironolactone/adverse effects , Spironolactone/pharmacokinetics , Urinalysis/methodsABSTRACT
Albuminuria development in hypertensive patients is an indicator of higher cardiovascular (CV) risk and renal damage. Chronic renin-angiotensin system (RAS) suppression facilitates blood pressure control but it does not prevent from albuminuria development. We pursued the identification of protein indicators in urine behind albuminuria development in hypertensive patients under RAS suppression. Urine was collected from 100 patients classified in three groups according to albuminuria development: (a) patients with persistent normoalbuminuria; (b) patients developing de novo albuminuria; (c) patients with maintained albuminuria. Quantitative analysis was performed in a first discovery cohort by isobaric labeling methodology. Alterations of proteins of interest were confirmed by target mass spectrometry analysis in an independent cohort. A total of 2416 proteins and 1223 functional categories (coordinated protein responses) were identified. Immune response, adhesion of immune and blood cells, and phagocytosis were found significantly altered in patients with albuminuria compared to normoalbuminuric individuals. The complement system C3 increases, while Annexin A1, CD44, S100A8 and S100A9 proteins showed significant diminishment in their urinary levels when albuminuria is present. This study reveals specific links between immune response and controlled hypertension in patients who develop albuminuria, pointing to potential protein targets for novel and future therapeutic interventions.
ABSTRACT
Albuminuria is an indicator of cardiovascular risk and renal damage in hypertensive individuals. Chronic renin-angiotensin system (RAS) suppression facilitates blood pressure control and prevents development of new-onset-albuminuria. A significant number of patients, however, develop albuminuria despite chronic RAS blockade, and the physiopathological mechanisms are underexplored. Urinary exosomes reflect pathological changes taking place in the kidney. The objective of this work was to examine exosomal protein alterations in hypertensive patients with albuminuria in the presence of chronic RAS suppression, to find novel clues underlying its development. Patients were followed-up for three years and were classified as: a) patients with persistent normoalbuminuria; b) patients developing de novo albuminuria; and c) patients with maintained albuminuria. Exosomal protein alterations between groups were identified by isobaric tag quantitation (iTRAQ). Confirmation was approached by target analysis (SRM). In total, 487 proteins were identified with high confidence. Specifically, 48 proteins showed an altered pattern in response to hypertension and/or albuminuria. Out of them, 21 proteins interact together in three main functional clusters: glycosaminoglycan degradation, coagulation and complement system, and oxidative stress. The identified proteins constitute potential targets for drug development and may help to define therapeutic strategies to evade albuminuria progression in hypertensive patients chronically treated.
Subject(s)
Albuminuria/metabolism , Exosomes/metabolism , Hypertension/metabolism , Proteome , Proteomics , Aged , Biomarkers , Chromatography, Liquid , Humans , Hypertension/urine , Middle Aged , Protein Interaction Mapping , Protein Interaction Maps , Proteomics/methods , ROC Curve , Renin-Angiotensin System , Tandem Mass Spectrometry , WorkflowABSTRACT
Hypertension (HTN) is increasing in prevalence, and albuminuria is a strong indicator of cardiovascular risk and renal damage progression. Despite blood pressure control with chronic treatment, a relevant subgroup of patients develop albuminuria. However, the biological factors responsible for albuminuria development and progression are underexplored. We aimed to identify key metabolic targets and biological pathways involved in the negative progression of cardiovascular and renal damage in hypertensives undergoing chronic treatment. A series of 1533 patients were followed for 5 years to investigate the evolution of albuminuria. Patients were classified as: (1) patients with persistent normoalbuminuria; (2) patients developing de novo albuminuria; and (3) patients with maintained albuminuria. At the end of follow-up, urine from 30 nonhypertensive subjects (control group) and a representative cohort of 118 patients was collected for metabolomic analysis. Metabolic patterns of interest were identified in a first discovery phase by nuclear magnetic resonance and further confirmed by liquid chromatography-mass spectrometry. Metabolites corresponding to HTN or albuminuria were measured in a prospective study carried out in 35 individuals still in normoalbuminuria, to evaluate their potential as predictors of albuminuria development. Nine metabolites were significantly altered, linking ß-alanine metabolism, arginine and proline metabolism, and tricarboxylic acid cycle. The prospective study revealed a panel composed of guanidinoacetate, glutamate, and pantothenate, which was able to predict development of albuminuria. These metabolic signatures open new possibilities in hypertensive therapy and cardiovascular risk control, providing prompt and more efficient intervention, particularly in patients with worse cardiovascular prognosis.
Subject(s)
Albuminuria/metabolism , Albuminuria/urine , Disease Progression , Hypertension/metabolism , Hypertension/urine , Metabolome , Aged , Albuminuria/pathology , Albuminuria/physiopathology , Female , Glomerular Filtration Rate , Humans , Hypertension/complications , Hypertension/physiopathology , Male , Metabolic Networks and Pathways , Middle Aged , Proton Magnetic Resonance Spectroscopy , Renin-Angiotensin SystemABSTRACT
BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death globally, being atherosclerosis the main cause. Main risk factors are known and current effort is very much dedicated to improve prevention. However, the asymptomatic and silent course of atherosclerosis hampers an accurate and individualized risk evaluation. OBJECTIVES: Here we investigate subjacent molecular changes taking place in arterial tissue which can be ultimately translated in a measurable fingerprint in plasma. METHODS: First, we applied a combined approach to find out main molecular alterations at protein and metabolite level in response to early atherosclerosis development in a rabbit model. A potential reflection of all these alterations observed in aortic tissue was investigated in rabbit plasma and further analyzed in a translational study in human plasma from 62 individuals. RESULTS: Data link the structural remodeling taking place in atherosclerotic arteries in terms of loss of contractile properties and favored cellular migration, with an up-regulation of integrin linked kinase, tropomyosin isoform 2 and capping protein gelsolin-like, and a down-regulation of vinculin. A molecular response to oxidative stress is evidenced, involving changes in the glucose metabolism enzymes pyruvate kinase (PKM) and phosphoglycerate kinase (PGK), and pyruvate. Up-regulation of aspartate connects different changes observed in amino acid metabolism and, additionally, alterations in the phosphatidylcholine route of the glycerophospholipid metabolism were found. CONCLUSIONS: A specific molecular marker panel composed by PKM, valine and pyruvate is shown here linked to cardiovascular risk.