Rationale and design of the CV-PREVITAL study: an Italian multiple cohort randomised controlled trial investigating innovative digital strategies in primary cardiovascular prevention

INTRODUCTION

Prevention of cardiovascular disease (CVD) is of key importance in reducing morbidity, disability and mortality worldwide. Observational studies suggest that digital health interventions can be an effective strategy to reduce cardiovascular (CV) risk. However, evidence from large randomised clinical trials is lacking.

METHODS AND ANALYSIS

The CV-PREVITAL study is a multicentre, prospective, randomised, controlled, open-label interventional trial designed to compare the effectiveness of an educational and motivational mobile health (mHealth) intervention versus usual care in reducing CV risk. The intervention aims at improving diet, physical activity, sleep quality, psycho-behavioural aspects, as well as promoting smoking cessation and adherence to pharmacological treatment for CV risk factors. The trial aims to enrol approximately 80 000 subjects without overt CVDs referring to general practitioners' offices, community pharmacies or clinics of Scientific Institute for Research, Hospitalization and Health Care (Italian acronym IRCCS) affiliated with the Italian Cardiology Network. All participants are evaluated at baseline and after 12 months to assess the effectiveness of the intervention on short-term endpoints, namely improvement in CV risk score and reduction of major CV risk factors. Beyond the funded life of the study, a long-term (7 years) follow-up is also planned to assess the effectiveness of the intervention on the incidence of major adverse CV events. A series of ancillary studies designed to evaluate the effect of the mHealth intervention on additional risk biomarkers are also performed.

ETHICS AND DISSEMINATION

This study received ethics approval from the ethics committee of the coordinating centre (Monzino Cardiology Center; R1256/20-CCM 1319) and from all other relevant IRBs and ethics committees. Findings are disseminated through scientific meetings and peer-reviewed journals and via social media. Partners are informed about the study's course and findings through regular meetings.

TRIAL REGISTRATION NUMBER

NCT05339841.

Evaluation of Left Ventricle Function by Regional Fractional Area Change (RFAC) in a Mouse Model of Myocardial Infarction Secondary to Valsartan Treatment

Aim

Left ventricle (LV) regional fractional area change (RFAC) measured by cardiac magnetic resonance (CMR) allows the non-invasive localization and quantification of the degree of myocardial infarction (MI), and could be applied to assess the effectiveness of pharmacological or regenerative therapies. Here we investigate the ability of RFAC to identify regional dysfunction and discriminate the effect of pharmacological treatment with valsartan, a selective antagonist of angiotensin II type 1 receptor, in a model of MI.

Methods and Results

C57BL/6N mice, undergoing coronary artery ligation, were divided into two groups: untreated (MI) or treated with valsartan (MI+Val). Sham-operated mice were used as a control. Cardiac dimensions and function were assessed at baseline, 24 hours, 1 and 4 weeks post surgery by CMR and echocardiography. At sacrifice histology and whole-genome gene expression profiling were performed. RFAC was able to detect significant differences between treatment groups whereas the global ejection fraction was not. RFAC showed greater loss of regional contraction in remote non-infarcted myocardium in MI group than in MI+Val group. Consistently, in the same region MI+Val mice showed reduced myocyte hypertrophy, fibroblast proliferation, and fibrosis and modulation of target genes; in addition, left atrium volumes, appendage length and duct contraction were preserved.

Conclusion

In this study, RFAC effectively estimated the degree of systolic dysfunction and discriminated the regions preserved by pharmacological treatment. RFAC index is a promising tool to monitor changes in LV contraction and to assess the effectiveness of therapeutic regimens in clinical settings.

Shear stress and VEGF enhance endothelial differentiation of human adipose-derived stem cells

Herein we combine chemical and mechanical stimulation to investigate the effects of vascular endothelial growth factor (VEGF) and physiological shear stress in promoting the differentiation human adipose derived stem cells (ADSCs) into endothelial cells. ADSCs were isolated and characterized; endothelial differentiation was promoted by culturing confluent cells in 50 ng/ml VEGF under physiological shear stress for up to 14 days. Afterwards, endothelial cells were seeded onto collagen or acellular aortic valve matrices and exposed to four culture conditions: shear stress + VEGF; shear stress - VEGF; static + VEGF and static - VEGF. After 7 days, phenotype was investigated. ADSCs subjected to shear stress and VEGF express a comprehensive range of specific endothelial markers (vWF, eNOS and FLT-1 after 7 days and CD31, FLk-1 and VE-cadherin after 14 days) and maintain the phenotype when seeded onto scaffolds. Our protocol proved to be an efficient source of endothelial-like cells for tissue engineering based on autologous ADSC.

Expression of dual nucleotides/cysteinyl-leukotrienes receptor GPR17 in early trafficking of cardiac stromal cells after myocardial infarction

GPR17 is a G_i-coupled dual receptor activated by uracil-nucleotides and cysteinyl-leukotrienes. These mediators are massively released into hypoxic tissues. In the normal heart, GPR17 expression has been reported. By contrast, its role in myocardial ischaemia has not yet been assessed. In the present report, the expression of GPR17 was investigated in mice before and at early stages after myocardial infarction by using immunofluorescence, flow cytometry and RT-PCR. Before induction of ischaemia, results indicated the presence of the receptor in a population of stromal cells expressing the stem-cell antigen-1 (Sca-1). At early stages after ligation of the coronary artery, the receptor was expressed in Sca-1⁺ cells, and cells stained with Isolectin-B4 and anti-CD45 antibody. GPR17⁺ cells also expressed mesenchymal marker CD44. GPR17 function was investigated in vitro in a Sca-1⁺/CD31⁻ cell line derived from normal hearts. These experiments showed a migratory function of the receptor by treatment with UDP-glucose and leukotriene LTD4, two GPR17 pharmacological agonists. The GPR17 function was finally assessed in vivo by treating infarcted mice with Cangrelor, a pharmacological receptor antagonist, which, at least in part, inhibited early recruitment of GPR17⁺ and CD45⁺ cells. These findings suggest a regulation of heart-resident mesenchymal cells and blood-borne cellular species recruitment following myocardial infarction, orchestrated by GPR17.

Mechanical compliance and immunological compatibility of fixative-free decellularized/cryopreserved human pericardium

BACKGROUND

The pericardial tissue is commonly used to produce bio-prosthetic cardiac valves and patches in cardiac surgery. The procedures adopted to prepare this tissue consist in treatment with aldehydes, which do not prevent post-graft tissue calcification due to incomplete xeno-antigens removal. The adoption of fixative-free decellularization protocols has been therefore suggested to overcome this limitation. Although promising, the decellularized pericardium has not yet used in clinics, due to the absence of proofs indicating that the decellularization and cryopreservation procedures can effectively preserve the mechanical properties and the immunologic compatibility of the tissue.

PRINCIPAL FINDINGS

The aim of the present work was to validate a procedure to prepare decellularized/cryopreserved human pericardium which may be implemented into cardiovascular homograft tissue Banks. The method employed to decellularize the tissue completely removed the cells without affecting ECM structure; furthermore, uniaxial tensile loading tests revealed an equivalent resistance of the decellularized tissue to strain, before and after the cryopreservation, in comparison with the fresh tissue. Finally, immunological compatibility, showed a minimized host immune cells invasion and low levels of systemic inflammation, as assessed by tissue transplantation into immune-competent mice.

CONCLUSIONS

Our results indicate, for the first time, that fixative-free decellularized pericardium from cadaveric tissue donors can be banked according to Tissue Repository-approved procedures without compromising its mechanical properties and immunological tolerance. This tissue can be therefore treated as a safe homograft for cardiac surgery.

Characterization of porcine aortic valvular interstitial cell 'calcified' nodules

Valve interstitial cells populate aortic valve cusps and have been implicated in aortic valve calcification. Here we investigate a common in vitro model for aortic valve calcification by characterizing nodule formation in porcine aortic valve interstitial cells (PAVICs) cultured in osteogenic (OST) medium supplemented with transforming growth factor beta 1 (TGF-β1). Using a combination of materials science and biological techniques, we investigate the relevance of PAVICs nodules in modeling the mineralised material produced in calcified aortic valve disease. PAVICs were grown in OST medium supplemented with TGF-β1 (OST+TGF-β1) or basal (CTL) medium for up to 21 days. Murine calvarial osteoblasts (MOBs) were grown in OST medium for 28 days as a known mineralizing model for comparison. PAVICs grown in OST+TGF-β1 produced nodular structures staining positive for calcium content; however, micro-Raman spectroscopy allowed live, noninvasive imaging that showed an absence of mineralized material, which was readily identified in nodules formed by MOBs and has been identified in human valves. Gene expression analysis, immunostaining, and transmission electron microscopy imaging revealed that PAVICs grown in OST+TGF-β1 medium produced abundant extracellular matrix via the upregulation of the gene for Type I Collagen. PAVICs, nevertheless, did not appear to further transdifferentiate to osteoblasts. Our results demonstrate that 'calcified' nodules formed from PAVICs grown in OST+TGF-β1 medium do not mineralize after 21 days in culture, but rather they express a myofibroblast-like phenotype and produce a collagen-rich extracellular matrix. This study clarifies further the role of PAVICs as a model of calcification of the human aortic valve.

Induction of mesenchymal to endothelial transformation of adipose-derived stem cells

BACKGROUND AND AIM OF THE STUDY

Adipose tissue is a readily available source of multipotent adult stem cells for use in tissue engineering and regenerative medicine. Adipose-derived stem cells (ADSCs) are currently being investigated as a source of interstitial cells to populate tissue-engineered heart valve constructs. However, the ability of these cells to differentiate into endothelial cells that would be required to cover the surface of the valve cusps has not been fully investigated.

METHODS

ADSCs were isolated and characterized using immunofluorescence and flow cytometry. Endothelial differentiation was promoted by culturing confluent cells in the presence of 2% fetal calf serum and 50 ng/ml vascular endothelial growth factor. Differentiation was evaluated by immunofluorescence staining for endothelial markers, and an analysis of acetylated low-density lipoprotein (Ac-LDL) uptake. An assessment of tubular formation was performed using an in vitro angiogenesis assay.

RESULTS

Isolated ADSCs were positive for the mesenchymal markers CD105, CD73, CD29, CD90 and CD44, and negative for hematopoietic and endothelial markers. After a seven-day treatment period, approximately 15% of ADSCs expressed the endothelial marker von Willebrand factor, and 70% had lost the expression of smooth muscle a-actin. Treated cells also were able to incorporate Ac-LDL, and also to form tubular structures on Matrigel, unlike control cells.

CONCLUSION

Based on these results, ADSCs are capable of differentiating into cells with phenotypic and functional features of endothelial cells. These predifferentiated cells provide new options for the tissue engineering of heart valves, based on autologous mesenchymal stem cells.

NEU3 sialidase strictly modulates GM3 levels in skeletal myoblasts C2C12 thus favoring their differentiation and protecting them from apoptosis

Membrane-bound sialidase NEU3, often referred to as the "ganglioside sialidase," has a critical regulatory function on the sialoglycosphingolipid pattern of the cell membrane, with an anti-apoptotic function, especially in cancer cells. Although other sialidases have been shown to be involved in skeletal muscle differentiation, the role of NEU3 had yet to be disclosed. Herein we report that NEU3 plays a key role in skeletal muscle differentiation by strictly modulating the ganglioside content of adjacent cells, with special regard to GM3. Induced down-regulation of NEU3 in murine C2C12 myoblasts, even when partial, totally inhibits their capability to differentiate by increasing the GM3 level above a critical point, which causes epidermal growth factor receptor inhibition (and ultimately its down-regulation) and an higher responsiveness of myoblasts to the apoptotic stimuli.