Multi-omics in thoracic aortic aneurysm: the complex road to the simplification.

BACKGROUND: Thoracic aortic aneurysm (TAA) is a serious condition that affects the aorta, characterized by the dilation of its first segment. The causes of TAA (e.g., age, hypertension, genetic syndromes) are heterogeneous and contribute to the weakening of the aortic wall. This complexity makes treating this life-threatening aortopathy challenging, as there are currently no etiological therapy available, and pharmacological strategies, aimed at avoiding surgical aortic replacement, are merely palliative. Recent studies on novel therapies for TAA have focused on identifying biological targets and etiological mechanisms of the disease by using advanced -omics techniques, including epigenomics, transcriptomics, proteomics, and metabolomics approaches. METHODS: This review presents the latest findings from -omics approaches and underscores the importance of integrating multi-omics data to gain more comprehensive understanding of TAA. RESULTS: Literature suggests that the alterations in TAA mediators frequently involve members of pro-fibrotic process (i.e., TGF-ß signaling pathways) or proteins associated with cell/extracellular structures (e.g., aggrecans). Further analyses often reported the importance in TAA of processes as inflammation (PCR, CD3, leukotriene compounds), oxidative stress (chromatin OXPHOS, fatty acids), mitochondrial respiration and glycolysis/gluconeogenesis (e.g., PPARs and HIF1a). Of note, more recent metabolomics studies added novel molecular markers to the list of TAA-specific detrimental mediators (proteoglycans). CONCLUSION: It is increasingly clear that integrating data from different -omics branches, along with clinical data, is essential as well as complicated both to reveal hidden relevant information and to address complex diseases such as TAA. Importantly, recent progresses in metabolomics highlighted novel potential and unprecedented marks in TAA diagnosis and therapy.

Mercaptoalbumin Is Associated with Graft Patency in Patients Undergoing Coronary Artery Bypass Grafting.

Coronary artery bypass graft (CABG) surgery still represents the gold standard for patients with complex multivessel coronary artery disease. However, graft occlusion still occurs in a significant proportion of CABG conduits, and oxidative stress is currently considered to be a potential contributor. Human serum albumin (HSA) represents the main antioxidant in plasma through its reduced amino acid Cys34, which can efficiently scavenge several oxidants. In a nested case-control study including 36 patients with occluded grafts and 38 age- and sex-matched patients without occlusion, we assessed the levels of the native mercaptoalbumin (HSA-SH) and oxidized thiolated form of albumin (Thio-HSA) in relation with graft occlusion within 5 years after CABG. We found that the plasma level of preoperative HSA-SH was significantly lower in patients with occluded graft at 5 years follow-up than in patients with graft patency. Furthermore, low HSA-SH remained independently associated with graft occlusion even after adjusting for preoperative D-dimer, a well-known marker of activated coagulation recently found to be associated with graft occlusion. In conclusion, the preoperative level of HSA-SH is independently associated with graft occlusion in CABG and represents a measurable and potentially druggable predictor.

Long-term secondary cardiovascular prevention programme in patients subjected to coronary artery bypass surgery.

AIMS: Patients with coronary heart disease (CHD) are at very high risk of recurrent events. A strategy to reduce excess risk might be to deliver structured secondary prevention programmes, but their efficacy has been mostly evaluated in the short term and in experimental settings. This is a retrospective case-control study aimed at assessing, in the real world, the efficacy of a secondary prevention programme in reducing long-term coronary event recurrences after coronary artery bypass surgery (CABG). METHODS AND RESULTS: Programme participants (henceforth 'cases') were men and women aged <75 years subjected to CABG between 2002 and 2014, living within 100 km of the hospital. Key programme actions included optimization of treatments according to the most updated European preventive guidelines, surveillance of therapy adherence, and customized lifestyle counselling. Controls were analogous patients not involved in the programme because living farther than 100 km away, matched 1:1 with cases for gender, age at CABG, and year of CABG. Both groups (n = 1248) underwent usual periodic cardiology follow-up at our centre. Data on symptomatic or silent CHD recurrences were obtained from the hospital electronic health records. Cox analysis (adjusted for baseline differences between groups) shows that programme participation was associated with a significantly lower incidence throughout 5 years post-CABG of symptomatic [hazard ratio (95% confidence interval): 0.59 (0.38-0.94)] and silent [0.53 (0.31-0.89)] coronary recurrences. CONCLUSION: In a real-world setting, taking part in a structured longstanding secondary prevention programme, in addition to usual cardiology care, meaningfully lowers the risk of coronary recurrences.

Aortic Valve Sclerosis in High-Risk Coronary Artery Disease Patients.

Background: Current knowledge regarding the relationship between aortic valve sclerosis (AVSc), cardiovascular risk factors, and mortality in patients with known coronary artery disease (CAD) is still unclear. The present study aimed at investigating the prevalence of AVSc as well as its association with long-term all-cause mortality in high-risk CAD patients that has never been explored in large cohorts thus far. Methods and Results: In this retrospective and observational cohort study we enrolled high-risk CAD patients, hospitalized at Centro Cardiologico Monzino (CCM), Milan, Italy, between January 2006 and December 2016. The morphology and function of the aortic valve were assessed from the recorded echocardiographic images to evaluate the presence of AVSc, defined as a non-uniform thickening of the aortic leaflets with no consequences on hemodynamics. Data on 5-year all-cause mortality was retrieved from a Regional database. Of the 5,489 patients initially screened, 4,938 (mean age 67 ± 11 years, 3,954 [80%] men) were enrolled in the study. In the overall population, AVSc was detected in 2,138 (43%) patients. Multivariable LASSO regression revealed that age, female gender, diabetes mellitus, previous MI, and left ventricular ejection fraction were independently associated with AVSc. All-cause mortality (adjusted hazard ratio: 1.29, 95%CI: 1.05-1.58) was significantly higher in AVSc than in non-AVSc patients. Conclusions: AVSc is frequently detected in high-risk CAD patients and is associated with long-term mortality. Our findings corroborate the hypothesis that AVSc is an underestimated marker of systemic cardiovascular risk. Thus, AVSc detection may be used to improve long-term risk stratification of high-risk CAD patients.

Aortic Valve Sclerosis as an Important Predictor of Long-Term Mortality in Patients With Carotid Atheromatous Plaque Requiring Carotid Endarterectomy.

Background: A strong association between aortic valve sclerosis (AVSc), the earliest manifestation of calcific aortic valve disease, and atherosclerosis exists. The aim of the study was to evaluate the predictive capabilities of AVSc on long-term all-cause mortality, in patients requiring carotid endarterectomy (CEA). Methods and Results: 806 consecutive CEA patients were enrolled. Preoperative echocardiography was used to assess AVSc. Computed tomography angiography was applied for plaque characterization. Kaplan-Meier curves, Cox linear regression, and area under the receiving operator characteristic (AUC) curve analyses were used to evaluate the predictive capability of AVSc. Overall, 348 of 541 patients had AVSc (64%). Age, diabetes, and estimated glomerular filtration rate (eGFR) were associated with AVSc. In the 5-year follow-up, AVSc group had a mortality rate of 16.7% while in no-AVSc group was 7.8%. Independent predictors of all-cause mortality were age, sex, eGFR, left ventricular ejection fraction, and AVSc. After adjustments, AVSc was associated with a significant increase in all-cause mortality risk (hazard ratio, HR = 1.9; 95%CI: 1.04-3.54; p = 0.038). We stratify our cohort based on carotid atheromatous plaque-type: soft, calcified, and mixed-fibrotic. In patients with mixed-fibrotic plaques, the mortality rate of AVSc patients was 15.5% compared to 2.4% in no-AVSc patients. In this group, AVSc was associated with an increased long-term all-cause mortality risk with an adjusted HR of 12.8 (95%CI: 1.71-96.35; p = 0.013), and the AUC, combing eGFR and AVSc was 0.77 (p < 0.001). Conclusions: Our findings indicate that AVSc together with eGFR may be used to improve long-term risk stratification of patients undergoing CEA surgery.

Very Long-term Outcome of Minimally Invasive Direct Coronary Artery Bypass.

BACKGROUND: Minimally invasive direct coronary artery bypass (MIDCAB) is a well-established, low-impact surgical procedure for revascularization of the left descending coronary artery with the left internal mammary artery. This study aimed to evaluate safety, overall survival, and freedom from major adverse cardiocerebral-related events (MACCE) after 20 years of MIDCAB. METHODS: This study retrospectively collected a series of 141 patients who underwent MIDCAB between 1997 and 2017, to assess long-term outcome. A total of 133 patients who underwent revascularization of the left descending coronary artery with the left mammary artery through a full median sternotomy were analyzed. RESULTS: Actuarial survival rates on a Kaplan-Meier curve were 100%, 95%, 90%, 83%, and 70% at 1, 5, 10, 15, and 20 years, respectively. Freedom from MACCE, defined as myocardial infarction, stroke, and cardiac death, was 97%, 90%, 79%, 75%, and 61% at 1,5,10,15, and 20 years, respectively. At Cox multivariable analysis, age, cancer, and chronic renal insufficiency were found to be independent predictors affecting long-term survival, with a hazard ratio of 1.12 (P = .007), 17.63 (P < .001), and 5.16 (P = .03), respectively. The MIDCAB group showed a significantly shorter hospital length of stay and significantly lower rates of blood transfusions, cardiac-related events, and all-cause events compared with the full sternotomy group (P = .02 and P = .001, respectively). CONCLUSIONS: The very long-term clinical outcome of MIDCAB is satisfactory in terms of survival and freedom from MACCE. MIDCAB significantly reduces hospital length of stay and blood transfusions when compared with full sternotomy bypass surgery on the left descending coronary artery and appears to improve prognosis in terms of cardiac-related events and all-cause events effectively.

Prospective Evaluation of Clinico-Pathological Predictors of Postoperative Atrial Fibrillation: An Ancillary Study From the OPERA Trial.

BACKGROUND: Postoperative atrial fibrillation (POAF) occurs in 30% to 50% of patients undergoing cardiac surgery and is associated with increased morbidity and mortality. Prospective identification of structural/molecular changes in atrial myocardium that correlate with myocardial injury and precede and predict risk of POAF may identify new molecular pathways and targets for prevention of this common morbid complication. METHODS: Right atrial appendage samples were prospectively collected during cardiac surgery from 239 patients enrolled in the OPERA trial (Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation), fixed in 10% buffered formalin, and embedded in paraffin for histology. We assessed general tissue morphology, cardiomyocyte diameters, myocytolysis (perinuclear myofibril loss), accumulation of perinuclear glycogen, interstitial fibrosis, and myocardial gap junction distribution. We also assayed NT-proBNP (N-terminal pro-B-type natriuretic peptide), hs-cTnT, CRP (C-reactive protein), and circulating oxidative stress biomarkers (F2-isoprostanes, F3-isoprostanes, isofurans) in plasma collected before, during, and 48 hours after surgery. POAF was defined as occurrence of postcardiac surgery atrial fibrillation or flutter of at least 30 seconds duration confirmed by rhythm strip or 12-lead ECG. The follow-up period for all arrhythmias was from surgery until hospital discharge or postoperative day 10. RESULTS: Thirty-five percent of patients experienced POAF. Compared with the non-POAF group, they were slightly older and more likely to have chronic obstructive pulmonary disease or heart failure. They also had a higher European System for Cardiac Operative Risk Evaluation and more often underwent valve surgery. No differences in left atrial size were observed between patients with POAF and patients without POAF. The extent of atrial interstitial fibrosis, cardiomyocyte myocytolysis, cardiomyocyte diameter, glycogen score or Cx43 distribution at the time of surgery was not significantly associated with incidence of POAF. None of these histopathologic abnormalities were correlated with levels of NT-proBNP, hs-cTnT, CRP, or oxidative stress biomarkers. CONCLUSIONS: In sinus rhythm patients undergoing cardiac surgery, histopathologic changes in the right atrial appendage do not predict POAF. They also do not correlate with biomarkers of cardiac function, inflammation, and oxidative stress. Graphic Abstract: A graphic abstract is available for this article.

Association of Microvesicles With Graft Patency in Patients Undergoing CABG Surgery.

BACKGROUND: Graft patency is one of the major determinants of long-term outcome following coronary artery bypass graft surgery (CABG). Biomarkers, if indicative of the underlying pathophysiological mechanisms, would suggest strategies to limit graft failure. The prognostic value of microvesicles (MVs) for midterm graft patency has never been tested. OBJECTIVES: The aim of this study was to evaluate whether MV pre-operative signature (number, cellular origin, procoagulant phenotype) could predict midterm graft failure and to investigate potential functional role of MVs in graft occlusion. METHODS: This was a nested case-control substudy of the CAGE (CoronAry bypass grafting: factors related to late events and Graft patency) study that enrolled 330 patients undergoing elective CABG. Of these, 179 underwent coronary computed tomography angiography 18 months post-surgery showing 24% graft occlusion. Flow cytometry MV analysis was performed in 60 patients (30 per group with occluded [cases] and patent [control subjects] grafts) on plasma samples collected the day before surgery and at follow-up. RESULTS: Before surgery, cases had 2- and 4-fold more activated platelet-derived and tissue-factor positive MVs respectively than control subjects. The MV procoagulant capacity was also significantly greater. Altogether this MV signature properly classified graft occlusion (area under the curve 0.897 [95% confidence interval: 0.81 to 0.98]; p < 0.0001). By using an MV score (0 to 6), the odds ratio for occlusion for a score above 3 was 16.3 (95% confidence interval: 4.1 to 65.3; p < 0.0001). CONCLUSIONS: The pre-operative signature of MVs is independently associated with midterm graft occlusion in CABG patients and a cumulative MV score stratifies patients' risk. Because the MV signature mirrors platelet activation, patients with a high MV score could benefit from a personalized antiplatelet therapy.

A call to action becomes practice: cardiac and vascular surgery during the COVID-19 pandemic based on the Lombardy emergency guidelines.

OBJECTIVES: During the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pandemic, Northern Italy had to completely reorganize its hospital activity. In Lombardy, the hub-and-spoke system was introduced to guarantee emergency and urgent cardiovascular surgery, whereas most hospitals were dedicated to patients with coronavirus disease 2019 (COVID-19). The aim of this study was to analyse the results of the hub-and-spoke organization system. METHODS: Centro Cardiologico Monzino (Monzino) became one of the four hubs for cardiovascular surgery, with a total of eight spokes. SARS-CoV-2 screening became mandatory for all patients. New flow charts were designed to allow separated pathways based on infection status. A reorganization of spaces guaranteed COVID-19-free and COVID-19-dedicated areas. Patients were also classified into groups according to their pathological and clinical status: emergency, urgent and non-deferrable (ND). RESULTS: A total of 70 patients were referred to the Monzino hub-and-spoke network. We performed 41 operations, 28 (68.3%) of which were emergency/urgent and 13 of which were ND. The screening allowed the identification of COVID-19 (three patients, 7.3%) and non-COVID-19 patients (38 patients, 92.7%). The newly designed and shared protocols guaranteed that the cardiac patients would be divided into emergency, urgent and ND groups. The involvement of the telematic management heart team allowed constant updates and clinical discussions. CONCLUSIONS: The hub-and-spoke organization system efficiently safeguards access to heart and vascular surgical services for patients who require ND, urgent and emergency treatment. Further reorganization will be needed at the end of this pandemic when elective cases will again be scheduled, with a daily increase in the number of operations.

Preoperative neurological dysfunctions: what is their meaning in patients presenting with acute type A aortic dissection?

INTRODUCTION: Type A aortic dissection (AAD) is a life-threatening disease with very high mortality. The gold standard treatment is surgical, as medical treatment has been proven to be ineffective. It is still unclear the role of preoperative neurological dysfunction in the prognosis of the patient. Therefore, the choice of performing surgery in patients with neurological symptoms is still left to the surgeon at the time of the diagnosis. The aim of this study is to make a narrative review of the current literature about the management of patients with neurological symptoms in AAD patients. EVIDENCE ACQUISITION: A bibliographical research was performed on PubMed, looking for papers containing the words: "((preoperative neurological symptoms in type a aortic dissection) OR brain injury type A aortic dissection) AND ("2010"[Date - Publication]: "3000"[Date - Publication])". A total of 35 papers were found. EVIDENCE SYNTHESIS: A total of 6 papers were chosen to be reviewed. All of them concluded that even patients with severe neurological symptoms (up to comatose state) had a good chance to recover neurological functions after surgery if treated in the first hours from the onset of symptoms. Interestingly, a hemorrhagic stroke was rarely found. CONCLUSIONS: Preoperative neurological dysfunction have been long considered a contraindication to surgery. Nevertheless, several authors show neurological and survival good results in patients with preoperative neurological dysfunction. They also stress the importance of surgical timing finding in 5 to 10 hours the surgical time limit to improve neurological dysfunction. A preoperative neurological dysfunction could be considered a strong advice towards surgical intervention. It is time to change and consider prompt surgery not only for survival but also for cerebral protection.

Impact of Fractional Flow Reserve Derived From Coronary Computed Tomography Angiography on Heart Team Treatment Decision-Making in Patients With Multivessel Coronary Artery Disease: Insights From the SYNTAX III REVOLUTION Trial.

BACKGROUND: Fractional flow reserve (FFR) is a reliable tool for the functional assessment of coronary stenoses. FFR computed tomography (CT) derived (FFRCT) has shown to be accurate, but its clinical usefulness in patients with complex coronary artery disease remains to be investigated. The present study sought to determine the impact of FFRCT on heart team's treatment decision-making and selection of vessels for revascularization in patients with 3-vessel coronary artery disease. METHODS: The trial was an international, multicenter study randomizing 2 heart teams to make a treatment decision between percutaneous coronary interventions and coronary artery bypass grafting using either coronary computed tomography angiography or conventional angiography. The heart teams received the FFRCT and had to make a treatment decision and planning integrating the functional component of the stenoses. Each heart team calculated the anatomic SYNTAX score, the noninvasive functional SYNTAX score and subsequently integrated the clinical information to compute the SYNTAX score III providing a treatment recommendation, that is, coronary artery bypass grafting, percutaneous coronary intervention, or equipoise coronary artery bypass grafting-percutaneous coronary intervention. The primary objective was to determine the proportion of patients in whom FFRCT changed the treatment decision and planning. RESULTS: Overall, 223 patients were included. Coronary computed tomography angiography assessment was feasible in 99% of the patients and FFRCT analysis in 88%. FFRCT was available for 1030 lesions (mean FFRCT value 0.64±13). A treatment recommendation of coronary artery bypass grafting was made in 24% of the patients with coronary computed tomography angiography with FFRCT. The addition of FFRCT changed the treatment decision in 7% of the patients and modified selection of vessels for revascularization in 12%. With conventional angiography as reference, FFRCT assessment resulted in reclassification of 14% of patients from intermediate and high to low SYNTAX score tertile. CONCLUSIONS: In patients with 3-vessel coronary artery disease, a noninvasive physiology assessment using FFRCT changed heart team's treatment decision-making and procedural planning in one-fifth of the patients. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02813473.

Aortic Valve Sclerosis Adds to Prediction of Short-Term Mortality in Patients with Documented Coronary Atherosclerosis.

AIMS: Aortic valve sclerosis (AVSc), a non-uniform thickening of leaflets with an unrestricted opening, is characterized by inflammation, lipoprotein deposition, and matrix degradation. In the general population, AVSc predicts long-term cardiovascular mortality (+50%) even after adjustment for vascular risk factors and clinical atherosclerosis. We have hypothesized that AVSc is a risk-multiplier able to predict even short-term mortality. To address this issue, we retrospectively analyzed 90-day mortality of all patients who underwent isolated coronary artery bypass grafting (CABG) at Centro Cardiologico Monzino over a ten-year period (2006-2016). METHODS: We analyzed 2246 patients and 90-day all-cause mortality was 1.5% (31 deaths). We selected only patients deceased from cardiac causes (n = 29) and compared to alive patients (n = 2215). A cardiologist classified the aortic valve as no-AVSc (n = 1352) or AVSc (n = 892). Cox linear regression and integrated discrimination improvement (IDI) analyses were used to evaluate AVSc in predicting 90-day mortality. RESULTS: AVSc 90-day survival (97.6%) was lower than in no-AVSc (99.4%; p < 0.0001) with a hazard ratio (HR) of 4.0 (95%CI: 1.78, 9.05; p < 0.0001). The HR for AVSc, adjusted for propensity score, was 2.7 (95%CI: 1.17, 6.23; p = 0.02) and IDI statistics confirmed that AVSc significantly adds (p < 0.001) to the identification of high-risk patients than EuroSCORE II alone. CONCLUSION: Our data supports the hypothesis that a risk stratification strategy based on AVSc, added to ESII, may allow better recognition of patients at high-risk of short-term mortality after isolated surgical myocardial revascularization. Results from this study warrant further confirmation.

Cardiovascular morbidity and mortality in patients with aortic valve calcification: A systematic review and meta-analysis.

BACKGROUND: Aortic valve calcification (AVC) is an active process that involves inflammation, disorganization of matrix disposition, lipid accumulation and lamellar bone formation. AVC without hemodynamic changes has been associated with cardiovascular (CV) risk factors and increased risk of coronary and CV events. Nowadays, echocardiography is the standard imaging technique to evaluate aortic valve pathologies. However, cardiac computed tomography (CT) allows high accuracy and reproducible measurement of AVC, without exposing the patients to excessive radiation or contrast administration. AIMS: To better understand if AVC assessment may improve CV risk-prediction, we performed a systematic search and meta-analysis of literature studies, evaluating the relationship among AVC, coronary artery disease (CAD), and overall mortality. METHODS AND RESULTS: A detailed search, according to PRISMA guidelines, was performed to identify all available studies investigating AVC, measured by CT scan, and CV events. Thirteen studies on 3,782 AVC patients and 32,890 controls were included in the final analysis. Patients with AVC have a higher risk of CAD (OR 1.7, 95%CI: 1.04-2.87; p = 0.04) when compared to controls. We also found an association between AVC and coronary artery calcification (OR 3.8; 95%CI: 2.4-6.0; p < 0.001.) Finally, AVC had 93.2% specificity for overall mortality (95%CI: 92.8-93.6) with a negative predictive value of 98.8% (95%CI: 98.7-98.8). CONCLUSION: AVC is associated with coronary artery calcification and overall mortality. The present data cannot support the use of cardiac CT over echocardiography for AVC assessment in all patients, but when cardiac CT is performed for suspected CAD, AVC evaluation may contribute to risk stratification and patient management. Ad hoc designed studies should address this issue in the next future.

Endothelial Dysfunction in Patients with Severe Mitral Regurgitation.

Mitral valve prolapse (MVP) is the most common cause of severe mitral regurgitation. It has been reported that MVP patients-candidates for mitral valve repair (MVRep)-showed an alteration in the antioxidant defense systems as well as in the L-arginine metabolic pathway. In this study, we investigate if oxidative stress and endothelial dysfunction are an MVP consequence or driving factors. Forty-five patients undergoing MVRep were evaluated before and 6 months post surgery and compared to 29 controls. Oxidized (GSSG) and reduced (GSH) forms of glutathione, and L-arginine metabolic pathway were analyzed using liquid chromatography-tandem mass spectrometry methods while osteoprotegerin (OPG) through the ELISA kit and circulating endothelial microparticles (EMP) by flow cytometry. Six-month post surgery, in MVP patients, the GSSG/GSH ratio decreased while symmetric and asymmetric dimethylarginines levels remained comparable to the baseline. Conversely, OPG levels significantly increased when compared to their baseline. Finally, pre-MVRep EMP levels were significantly higher in patients than in controls and did not change post surgery. Overall, these results highlight that MVRep completely restores the increased oxidative stress levels, as evidenced in MVP patients. Conversely, no amelioration of endothelial dysfunction was evidenced after surgery. Thus, therapies aimed to restore a proper endothelial function before and after surgical repair could benefit MVP patients.

Abnormal DNA Methylation Induced by Hyperglycemia Reduces CXCR 4 Gene Expression in CD 34+ Stem Cells.

Background CD 34+ stem/progenitor cells are involved in vascular homeostasis and in neovascularization of ischemic tissues. The number of circulating CD 34+ stem cells is a predictive biomarker of adverse cardiovascular outcomes in diabetic patients. Here, we provide evidence that hyperglycemia can be "memorized" by the stem cells through epigenetic changes that contribute to onset and maintenance of their dysfunction in diabetes mellitus. Methods and Results Cord-blood-derived CD 34+ stem cells exposed to high glucose displayed increased reactive oxygen species production, overexpression of p66shc gene, and downregulation of antioxidant genes catalase and manganese superoxide dismutase when compared with normoglycemic cells. This altered oxidative state was associated with impaired migration ability toward stromal-cell-derived factor 1 alpha and reduced protein and mRNA expression of the C-X-C chemokine receptor type 4 ( CXCR 4) receptor. The methylation analysis by bisulfite Sanger sequencing of the CXCR 4 promoter revealed a significant increase in DNA methylation density in high-glucose CD 34+ stem cells that negatively correlated with mRNA expression (Pearson r=-0.76; P=0.004). Consistently, we found, by chromatin immunoprecipitation assay, a more transcriptionally inactive chromatin conformation and reduced RNA polymerase II engagement on the CXCR 4 promoter. Notably, alteration of CXCR 4 DNA methylation, as well as transcriptional and functional defects, persisted in high-glucose CD 34+ stem cells despite recovery in normoglycemic conditions. Importantly, such an epigenetic modification was thoroughly confirmed in bone marrow CD 34+ stem cells isolated from sternal biopsies of diabetic patients undergoing coronary bypass surgery. Conclusions CD 34+ stem cells "memorize" the hyperglycemic environment in the form of epigenetic modifications that collude to alter CXCR 4 receptor expression and migration.

Impact of Oxidative Stress and Protein S-Glutathionylation in Aortic Valve Sclerosis Patients with Overt Atherosclerosis.

Aortic valve sclerosis (AVSc) is characterized by non-uniform thickening of the leaflets without hemodynamic changes. Endothelial dysfunction, also caused by dysregulation of glutathione homeostasis expressed as ratio between its reduced (GSH) and its oxidised form (GSSG), could represent one of the pathogenic triggers of AVSc. We prospectively enrolled 58 patients with overt atherosclerosis and requiring coronary artery bypass grafting (CABG). The incidence of AVSc in the studied population was 50%. The two groups (No-AVSc and AVSc) had similar clinical characteristics. Pre-operatively, AVSc group showed significantly lower GSH/GSSG ratio than No-AVSc group (p = 0.02). Asymmetric dimethylarginine (ADMA) concentration was significantly higher in AVSc patients compared to No-AVSc patients (p < 0.0001). Explanted sclerotic aortic valves presented a significantly increased protein glutathionylation (Pr-SSG) than No-AVSc ones (p = 0.01). In vitro, inhibition of glutathione reductase caused ß-actin glutathionylation, activation of histone 2AX, upregulation of α2 smooth muscle actin (ACTA2), downregulation of platelet and endothelial cell adhesion molecule 1 (PECAM1) and cadherin 5 (CDH5). In this study, we showed for the first time that the dysregulation of glutathione homeostasis is associated with AVSc. We found that Pr-SSG is increased in AVSc leaflets and it could lead to EndMT via DNA damage. Further studies are warranted to elucidate the causal role of Pr-SSG in aortic valve degeneration.

Cell therapy for heart disease after 15 years: Unmet expectations.

Over the past two decades cardiac cell therapy (CCT) has emerged as a promising new strategy to cure heart diseases at high unmet need. Thousands of patients have entered clinical trials for acute or chronic heart conditions testing different cell types, including autologous or allogeneic bone marrow (BM)-derived mononuclear or selected cells, BM- or adipose tissue-derived mesenchymal cells, or cardiac resident progenitors based on their potential ability to regenerate scarred or dysfunctional myocardium. Nowadays, the original enthusiasm surrounding the regenerative medicine field has been cushioned by a cumulative body of evidence indicating an inefficient or modest efficacy of CCT in improving cardiac function, along with the continued lack of indisputable proof for long-term prognostic benefit. In this review, we have firstly comprehensively outlined the positive and negative results of cell therapy studies in patients with acute myocardial infarction, refractory angina and chronic heart failure. Next, we have discussed cell therapy- and patient-related variables (e.g. cell intrinsic and extrinsic characteristics as well as criteria of patient selection and proposed methodologies) that might have dampened the efficacy of past cell therapy trials. Finally, we have addressed critical factors to be considered before embarking on further clinical trials.