Simona Greco1, Germana Zaccagnini1, Paola Fuschi1, Christine Voellenkle1, Matteo Carrara1, Iman Sadeghi1, Claudia Bearzi2, Biagina Maimone1, Serenella Castelvecchio3, Konstantinos Stellos4, Carlo Gaetano5, Lorenzo Menicanti3, Fabio Martelli1. 1. Molecular Cardiology Laboratory, IRCCS Policlinico San Donato, Via Morandi, 30 20097 San Donato, Milanese, Milan, Italy. 2. Institute of Cell Biology and Neurobiology (IBCN), National Research Council of Italy (CNR), Monterotondo Scalo, Rome, Italy. 3. Department of Cardiac Surgery, IRCCS Policlinico San Donato, Milan, Italy. 4. Laboratory of RNA Metabolism and Vascular Inflammation, Institute of Cardiovascular Regeneration, Centre of Molecular Medicine, Goethe University Frankfurt, Frankfurt/Main, Germany. 5. Division of Cardiovascular Epigenetics, Department of Cardiology and Internal Medicine Clinic III, Department of Cardiology, Goethe University, Frankfurt/Main, Germany.
Abstract
AIMS: Antisense long noncoding RNAs (ncRNAs) are transcripts emerging from the opposite strand of a coding-RNA region and their role in heart failure (HF) is largely unknown. Additionally, HF and Alzheimer's disease (AD) share several non-genetic effectors and risk factors. We investigated the regulation of the β-secretase-1 (BACE1) gene and of its antisense transcript BACE1-AS in ischaemic HF. METHODS AND RESULTS: BACE1 and BACE1-AS expression was measured in left ventricle biopsies from 18 patients affected by non-end stage ischaemic HF and 17 matched controls. The levels of both transcripts were increased in HF patients. Likewise, both transcripts increased also in a mouse model of ischaemic HF, and their expression was directly correlated. BACE1-AS was expressed by all cardiac cell types and BACE1-AS up- or down-modulation in cultured cardiomyocytes and endothelial cells induced a concordant regulation of the cognate BACE1 transcript. Interestingly, BACE1 increase also induced the intracellular accumulation of its product β-amyloid. In keeping with these findings, higher BACE1 protein and β-amyloid peptide levels were also observed in HF. Moreover, increased β-amyloid 1-40 was also found in the plasma of HF patients. Transcriptomic changes of BACE1-AS overexpressing and β-amyloid 1-40 treated cells were largely overlapping and indicated changes of relevant biological process such as 'cell cycle and proliferation', 'apoptosis', and 'DNA repair' as well as 'TGFβ-, TNFα-, p38-, EGFR-signalling', suggesting a potential maladaptive role of the BACE1-AS/BACE1/β-amyloid axis. Accordingly, the administration of β-amyloid peptides decreased the cell viability in endothelial cells and in both human IPS-derived and mouse cardiomyocytes. Moreover, both β-amyloid treatment and BACE1-AS overexpression increased endothelial cell apoptosis, and this effect was prevented by BACE1 silencing. CONCLUSION: Given the neurotoxic role of β-amyloid in AD, dysregulation of the BACE1/BACE1-AS/β-amyloid axis might be relevant in HF pathogenesis, further implicating ncRNAs in the complex scenario of proteotoxicity in cardiac dysfunction. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: Antisense long noncoding RNAs (ncRNAs) are transcripts emerging from the opposite strand of a coding-RNA region and their role in heart failure (HF) is largely unknown. Additionally, HF and Alzheimer's disease (AD) share several non-genetic effectors and risk factors. We investigated the regulation of the β-secretase-1 (BACE1) gene and of its antisense transcript BACE1-AS in ischaemic HF. METHODS AND RESULTS: BACE1 and BACE1-AS expression was measured in left ventricle biopsies from 18 patients affected by non-end stage ischaemic HF and 17 matched controls. The levels of both transcripts were increased in HF patients. Likewise, both transcripts increased also in a mouse model of ischaemic HF, and their expression was directly correlated. BACE1-AS was expressed by all cardiac cell types and BACE1-AS up- or down-modulation in cultured cardiomyocytes and endothelial cells induced a concordant regulation of the cognate BACE1 transcript. Interestingly, BACE1 increase also induced the intracellular accumulation of its product β-amyloid. In keeping with these findings, higher BACE1 protein and β-amyloid peptide levels were also observed in HF. Moreover, increased β-amyloid 1-40 was also found in the plasma of HF patients. Transcriptomic changes of BACE1-AS overexpressing and β-amyloid 1-40 treated cells were largely overlapping and indicated changes of relevant biological process such as 'cell cycle and proliferation', 'apoptosis', and 'DNA repair' as well as 'TGFβ-, TNFα-, p38-, EGFR-signalling', suggesting a potential maladaptive role of the BACE1-AS/BACE1/β-amyloid axis. Accordingly, the administration of β-amyloid peptides decreased the cell viability in endothelial cells and in both human IPS-derived and mouse cardiomyocytes. Moreover, both β-amyloid treatment and BACE1-AS overexpression increased endothelial cell apoptosis, and this effect was prevented by BACE1 silencing. CONCLUSION: Given the neurotoxic role of β-amyloid in AD, dysregulation of the BACE1/BACE1-AS/β-amyloid axis might be relevant in HF pathogenesis, further implicating ncRNAs in the complex scenario of proteotoxicity in cardiac dysfunction. Published on behalf of the European Society of Cardiology. All rights reserved.