Seeking Novel Personalized and Sex-Specific Strategies for the Prevention and Treatment of Heart Failure Based on the Assessment of β1-Adrenergic Receptor Desensitization: The Contribution to the HEAL ITALIA Project

<b>Background:</b> This study is part of the HEAL ITALIA partnership, funded by the National Recovery and Resilience Plan (PNRR) and the European Union. Heart failure (HF) is a serious health problem, with a reduced density of the β1-adrenergic receptor (β1-AR) in the myocardium as a hallmark. It is unclear whether this downregulation causes dysfunction or represents an epiphenomenon. Recent evidence implicates oxidative stress and mitochondrial signaling, particularly through the 18 kDa translocator protein (TSPO), in the regulation of the β1-AR, with possible modulation by estrogen. <b>Objectives:</b> To determine (1) the role of β1-AR desensitization in the onset and development of HF; (2) whether monocytes can represent a suitable ex vivo model for sex-oriented mechanistic studies in the cardiac field; (3) whether monocytes isolated from peripheral blood of patients can represent a diagnostic and/or therapy response biomarker by monitoring β1-AR density; (4) whether and how the mitochondrial receptor TSPO is involved in the β1-AR dysregulation observed in HF; and (5) whether the mechanisms linked to the onset of HF are regulated in a sex-specific manner through the effect of estrogen and/or the X chromosome on the expression of specific microRNAs. <b>Methods:</b> Using an integrated in vitro-ex vivo-in vivo methodological approach, we will evaluate the density of β1/β2-AR receptors, the downstream signaling (GRK2/β-arrestin), mitochondrial and redox parameters, and miRNA profiles in human monocytes and cardiomyocytes, and in mouse hearts after HF following pressure overload. <b>Conclusions:</b> The goal is to better understand the mechanisms underlying β1-AR desensitization, verify monocytes as peripheral markers of disease progression and response to therapy, and provide potentially useful information for the development of gender-specific therapies for heart failure.