Vecchi e nuovi indici infiammatori nel monitoraggio dei dispositivi di assistenza ventricolare in pazienti con scompenso cardiaco grave

Introduzione. Lo scompenso cardiaco (SC), per l’alto grado di morbilità e mortalità, è la malattia cardiovascolare con il più elevato impatto socio-sanitario. A fronte di una sempre crescente disponibilità di nuovi trattamenti terapeutici, per i pazienti con SC in fase terminale spesso il trapianto d’organo rimane l’unico intervento possibile. Dato il limitato numero di donatori d’organo e il contemporaneo aumento di pazienti con questa patologia, i dispositivi di assistenza ventricolare sinistra (LVAD), che permettono di recuperare funzionalità contrattile, assumono sempre maggiore importanza, principalmente come ponte al trapianto. La conoscenza dei meccanismi molecolari associati al progressivo deterioramento della funzione cardiaca (rimodellamento cardiaco) costituisce la base per identificare biomarcatori da utilizzare sia nella pratica clinica per il monitoraggio in tempo reale del paziente con LVAD sia come indici prognostici. In questo contesto, il processo infiammatorio sembra avere un ruolo centrale ed essere strettamente correlato con la prognosi. Scopo. Questo lavoro di tesi si propone di valutare: 1. se l’impianto di LVAD in pazienti con SC grave è in grado di modulare il processo di flogosi, sia a livello cellulare cardiaco che sistemico; 2. se i livelli basali dei diversi indici di flogosi sono correlati con diagnosi e prognosi. Metodi. Campioni di tessuto cardiaco sono stati ottenuti da pazienti con SC in fase terminale sottoposti a impianto di LVAD come ponte al trapianto (classe NYHA III-IV; età 45±2 anni; LVEF%: 24±4). In base al momento del prelievo della biopsia sono stati suddivisi 2 gruppi: 1) gruppo pre-LVAD (n=22), al momento dell’impianto del LVAD dalla regione apicale; 2) gruppo post LVAD (n=7), al momento dell’espianto cardiaco da apice, parete anteriore e laterale. Oltre agli indici infiammatori classici, Interleuchina (IL)-6, IL-8 e Tumor Necrosis Factor (TNF)-, sono state valutate alcune cardiochine, fra cui IL-33 e il suo recettore ST2, e il sistema dell’adiponectina, una proteina con azione anti-infiammatoria e cardioprotettiva. RNA e proteine totali sono stati estratti simultaneamente dai campioni tessutali con il metodo del fenolo/cloroformio/guanidina-tiocianato; l’espressione a livello di mRNA dei marcatori in oggetto è stata valutata tramite Real time-PCR dopo selezione dei geni di riferimento. Saggi immunometrici specifici sono stati utilizzati per le determinazioni a livello proteico e nel circolo periferico. Risultati. Per la selezione dei geni di riferimento da utilizzare per la normalizzazione dei risultati sperimentali di Real-time PCR, sono stati analizzati nove possibili geni candidati; PPIA, YWHAZ, RPL13a sono risultati i geni più stabili per il sistema in studio. Dopo supporto con LVAD, è stato osservato un significativo aumento dell’espressione a livello di mRNA dei principali indici infiammatori (IL-6: 0.063 ± 0.013 vs 0.773 ± 0.281, media ± sem, p<0.001; IL-33: 025 ± 0.046, p<0.001; ST2: 0.035 ± 0.011 vs 0.824 ± 0.168, p<0.001). In parallelo, l’adiponectina e i suoi recettori sono risultati modificati dopo LVAD. Per quanto riguarda la correlazione dei diversi biomarcatori con la prognosi, è stata osservata un’associazioni significativa fra l’espressione tessutale pre-LVAD di ST2 e la permanenza in terapia intensiva, uno degli indici di prognosi considerati (p=0.04). Rimane da valutare la correlazione di questi stessi parametri con i livelli circolanti dei biomarcatori in oggetto, la cui determinazione è attualmente in corso. Conclusioni. I risultati di questo lavoro di tesi indicano che l’impianto di LVAD in pazienti con SC grave induce un aumento significativo dell’espressione cardiaca di marcatori del processo di flogosi e significative alterazioni del sistema dell’adiponectina. Sono state inoltre osservate correlazioni significative fra la prognosi e l’espressione basale di questi indici. La determinazione dei rispettivi livelli circolanti, basalmente e a vari tempi durante il primo mese di supporto meccanico, permetterà di meglio definirne il ruolo prognostico

Association of Circulating Heme Oxygenase-1, Lipid Profile and Coronary Disease Phenotype in Patients with Chronic Coronary Syndrome

Background. The NF-E2-related factor 2 (Nrf2)/Heme Oxygenase-1 (HO-1) pathway has an emerging role in atherosclerosis. Activated by oxidative stress, it is deemed to exert athero-protective effects. We aimed at evaluating the relationships between plasma HO-1, clinical/molecular profiles and coronary disease patterns in patients with chronic coronary syndromes (CCS). Methods. HO-1 was measured in 526 patients (60 +/- 9 years, 318 males) with CCS. Coronary computed tomography angiography (CTA) and stress imaging were used to assess the disease phenotype (coronary atherosclerosis and myocardial ischemia) in a subgroup of 347 patients. Results. In the overall population, HO-1 median value (25-75 percentile) was 5.195 (1.75-8.25) ng/mL. Patients with higher HO-1 were more frequently male, had a higher BMI and lower LVEF%, but otherwise similar risk factors than the other patients. Their bio-humoral profile was characterized by higher markers of endothelial/myocardial dysfunction, but lower levels of cholesterol lipoproteins. Coronary artery disease was characterized by more diffuse atherosclerosis, with mainly non-obstructive and calcified plaques, and a higher prevalence of functional ischemia. Conclusion: In patients with CCS, higher plasma HO-1 levels are associated with lower cholesterol and a more diffuse but mainly non-obstructive coronary atherosclerosis, confirming a potential role for the Nrf2/HO-1 pathway as a protective feedback

Epigenetic Regulation of Cardiac Troponin Genes in Pediatric Patients with Heart Failure Supported by Ventricular Assist Device

Ventricular Assist Device (VAD) therapy is considered as a part of standard care for end-stage Heart Failure (HF) children unresponsive to medical management, but the potential role of miRNAs in response to VAD therapy on molecular pathways underlying LV remodeling and cardiac function in HF is unknown. The aims of this study were to evaluate the effects of VAD on miRNA expression profile in cardiac tissue obtained from HF children, to determine the putative miRNA targets by an in-silico analysis as well as to verify the changes of predicated miRNA target in the same cardiac samples. The regulatory role of selected miRNAs on predicted targets was evaluated by a dedicated in vitro study. miRNA profile was determined in cardiac samples obtained from 13 HF children [median: 29 months; 19 LVEF%; 9 Kg] by NGS before VAD implant (pre-VAD) and at the moment of heart transplant (Post-VAD). Only hsa-miR-199b-5p, hsa-miR-19a-3p, hsa-miR-1246 were differentially expressed at post-VAD when compared to pre-VAD, and validated by real-time PCR. Putative targets of the selected miRNAs were involved in regulation of sarcomere genes, such as cardiac troponin (cTns) complex. The expression levels of fetal ad adult isoforms of cTns resulted significantly higher after VAD in cardiac tissue of HF pediatric patients when compared with HF adults. An in vitro study confirmed a down-regulatory effect of hsa-miR-19a-3p on cTnC expression. The effect of VAD on sarcomere organization through cTn isoform expression may be epigenetically regulated, suggesting for miRNAs a potential role as therapeutic targets to improve heart function in HF pediatric patients

Effects of cerium oxide nanoparticles on hemostasis: Coagulation, platelets, and vascular endothelial cells

Cerium oxide nanoparticles (nanoceria [NC]) have attracted much attention in biomedicine due to their surface composition that confers interesting redox activities and regenerative properties. Studies have demonstrated that the application of NPs in biomedicine can influence components of hemostatic system, inducing blood clotting, alterations of blood cells, and endothelial cell functions. NC were tested in vitro to assess their hemocompatibility and anticoagulant, anti-inflammatory, and anti-senescence activity in human endothelial cells. Hemocompatibility has been evaluated in vitro looking at the impact of NC on coagulation times, fibrinogen, and platelet aggregation. The effect of NC on vascular endothelial cells were assayed by testing cell viability, antioxidant activity, anticoagulant (tissue factor [TF]-mRNA expression) and anti-inflammatory properties (VCAM-1 exposure, cytokine release), and senescence (telomere shortening). NC did not show significant effects on coagulation process, hemolysis, or platelet aggregation. In endothelial cells, NC did not affect cell viability, reduced oxidative stress, inhibited mRNA-TF expression, VCAM-1 expression, and cytokine release. Moreover, NC reduce telomere shortening, possibly counteracting premature senescence. The hemocompatibility combined with anticoagulant and anti-inflammatory phenotype and the ability of counteract the premature senescence in vascular cells make NC a promising therapeutic tool in oxidative stress-related conditions. \ua9 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019

Association of MMP9 with adverse features of plaque progression and residual inflammatory risk in patients with chronic coronary syndrome (CCS)

BACKGROUND AND AIMS MMP-9 is a predictor of atherosclerotic plaque instability and adverse cardiovascular events, but longitudinal data on the association between MMP9 and coronary disease progression are lacking. This study is aimed at investigating whether MMP9 is associated with atherosclerotic plaque progression and the related molecular basis in stable patients with chronic coronary syndrome (CCS). METHODS MMP9 serum levels were measured in 157 CCS patients (58 ± 8 years of age; 66% male) undergoing coronary computed tomography angiography at baseline and after a follow up period of 6.5 ± 1.1 years to assess progression of Total, Fibrous, Fibro-fatty, Necrotic Core, and Dense Calcium plaque volumes (PV). Gene expression analysis was evaluated in whole blood using a transcriptomic approach by RNA-seq. RESULTS At multivariate analysis, serum MMP9 was associated with annual change of Total and Necrotic Core PV (Coefficient 3.205, SE 1.321, P = 0.017; 1.449, SE 0.690, P = 0.038, respectively), while MMP9 gene expression with Necrotic Core PV (Coefficient 70.559, SE 32.629, P = 0.034), independently from traditional cardiovascular risk factors, medications, and presence of obstructive CAD. After transcriptomic analysis, MMP9 expression was linked to expression of genes involved in the innate immunity. CONCLUSIONS Among CCS patients, MMP9 is an independent predictive marker of progression of adverse coronary plaques, possibly reflecting the activity of inflammatory pathways conditioning adverse plaque phenotypes. Thus, blood MMP9 might be used for the identification of patients with residual risk even with optimal management of classical cardiovascular risk factors who may derive the greatest benefit from targeted anti-inflammatory drugs

Effect of coronary atherosclerosis and myocardial ischemia on plasma levels of high-sensitivity Troponin T and NT-proBNP in patients with stable angina

OBJECTIVE: Circulating levels of high-sensitivity cardiac troponin T (hs-cTnT) and N terminal probrain natriuretic peptide (NT-proBNP) are predictors of prognosis in patients with coronary artery disease (CAD). We aimed at evaluating the effect of coronary atherosclerosis and myocardial ischemia on cardiac release of hs-cTnT and NT-proBNP in patients with suspected CAD. APPROACH AND RESULTS: Hs-cTnT and NT-proBNP were measured in 378 patients (60.1±0.5 years, 229 males) with stable angina and unknown CAD enrolled in the Evaluation of Integrated Cardiac Imaging (EVINCI) study. All patients underwent stress imaging to detect myocardial ischemia and coronary computed tomographic angiography to assess the presence and characteristics of CAD. An individual computed tomographic angiography score was calculated combining extent, severity, composition, and location of plaques. In the whole population, the median (25-75 percentiles) value of plasma hs-cTnT was 6.17 (4.2-9.1) ng/L and of NT-proBNP was 61.66 (31.2-132.6) ng/L. In a multivariate model, computed tomographic angiography score was an independent predictor of the plasma hs-cTnT (coefficient 0.06, SE 0.02; P=0.0089), whereas ischemia was a predictor of NT-proBNP (coefficient 0.38, SE 0.12; P=0.0015). Hs-cTnT concentrations were significantly increased in patients with CAD with or without myocardial ischemia (P<0.005), whereas only patients with CAD and ischemia showed significantly higher levels of NT-proBNP (P<0.001). CONCLUSIONS: In patients with stable angina, the presence and extent of coronary atherosclerosis is related with circulating levels of hs-cTnT, also in the absence of ischemia, suggesting an ischemia-independent mechanism of hs-cTnT release. Obstructive CAD causing myocardial ischemia is associated with increased levels of NT-proBNP