HMGB1-mediated apoptosis and autophagy in ischemic heart diseases

Acute myocardial infarction (MI) and its consequences are the most common and lethal heart syndromes worldwide and represent a significant health problem. Following MI, apoptosis has been generally seen as the major contributor of the cardiomyocyte fate and of the resultant myocardial remodeling. However, in recent years, it has been discovered that, following MI, cardiomyocytes could activate autophagy in an attempt to protect themselves against ischemic stress and to preserve cardiac function. Although initially seen as two completely separate responses, recent works have highlighted the intertwined crosstalk between apoptosis and autophagy. Numerous researches have tried to unveil the mechanisms and the molecular players involved in this phenomenon and have identified in high-mobility group box 1 (HMGB1), a highly conserved non-histone nuclear protein with important roles in the heart, one of the major regulator. Thus, the aim of this mini review is to discuss how HMGB1 regulates these two responses in ischemic heart diseases. Indeed, a detailed understanding of the crosstalk between apoptosis and autophagy in these pathologies and how HMGB1 regulates them would be of tremendous help in developing novel therapeutic approaches aimed to promote cardiomyocyte survival and to diminish tissue injury following MI.