Bace1as Role in Heart Failure (BACE1AS-HF)

Overview

The objective of this project is 1) to explore the clinical relevance of BACE1-AS and BACE1 as therapeutic targets and 2) to evaluate their potentiality as biomarkers in ischemic heart failure (HF). The first aim will be studied by validating in left ventricle biopsies in patients with post-ischemic heart failure the transcriptome and DNA methylation status data obtained in cell lines where the expression of BACE1-AS has been modulated. The investigation of BACE1-AS and BACE1 as biomarkers will be obtained by using peripheral blood mononuclear cells (PBMCs) from patients with acute coronary syndrome (ACS) treated with percutaneous angioplasty (PCI) procedure and undergoing to left ventricular remodeling. Furthermore, PBMCs from patients with chronic ischemic HF recruited from the Istituti Clinici Scientifici Maugeri Pavia will be also used. From the data obtained from these patients and from non-decompensated subjects, the levels of BACE1-AS and BACE1 in the blood will be measured and correlated with each other and with β-amyloid levels (βA), as well as with clinically relevant parameters.

1.1) Validation of transcriptomic data obtained in vitro: The transcriptome of the AC16 cardiomyocyte cell line in which the expression of BACE1-AS was induced by lentivirus vectors will be analyzed, thus identifying the transcripts specifically modulated by BACE1-AS. The data obtained in vitro will be validated by analyzing the RNAs extracted from 20 HF patients and 20 controls. These RNA samples are already available thanks to the RNA\_HF\_AS project "Study of the transcriptome in heart failure and aortic stenosis" (San Raffaele Hospital - Milan, Ethics Committee CE 85/int/2016). 1.2) Validation of epigenetic data: The effect of BACE1-AS on the state of DNA methylation will be studied in the AC16 cardiomyocyte cell line. In over-expressing BACE1-AS cells, DNA hypomethylation will be evaluated by MS-HRM and pyrosequencing studies of bisulfite-modified genomic DNA of 69 enhancer sequences identified by us as candidates in preliminary studies. The data thus obtained will be validated in 20 cardiac biopsies from patients with post-ischemic HF and in 20 controls. Left ventricular biopsies will be taken after obtaining informed consent from 20 patients suffering from non-terminal dilated cardiomyopathy (DCM) undergoing left ventricular reconstruction (SVR) surgery at the San Donato Policlinico. A sufficient number of samples with these characteristics have already been obtained from IRCCS Policlinico San Donato as part of the RNA\_HF\_AS project (San Raffaele Hospital - Milan, Ethics Committee CE 85/int/2016). and not completely used for the study. 1.3) Study of the expression levels of BACE1-AS, BACE1 in PBMC of patients with ischemic cardiomyopathy. The expression levels of BACE1 and BACE1-AS will be measured in PBMCs from the following groups: Group 1: 130 ACS patients with left ventricular systolic dysfunction (left ventricular ejection fraction (LVEF) \< 45%) at 12 months follow-up after PCI, as well as 100 control subjects, recruited from the Interventional Cardiology Unit of the IRCCS Policlinico San Donato. The measurements of BACE1, BACE1-AS and βA will be carried out at the Molecular Cardiology Laboratory of the IRCCS Policlinico San Donato. These activities are included among those approved in the RNA\_ACS protocol (Ethics Committee of the San Raffaele Hospital - Milan 14/int/2020) "RNA as prognostic biomarkers in patients with acute coronary syndrome" Group 2: 240 patients with chronic post-ischemic HF and 120 age/sex-matched healthy controls. The recruitment of this group and measurements of BACE1, BACE1-AS and βA will be carried out at the Istituti Clinici Scientifici Maugeri Pavia.