Hypoxia sensing in resident cardiac macrophages regulates monocyte fate specification following ischemic heart injury.

Myocardial infarction initiates cardiac remodeling and is central to heart failure pathogenesis. Following myocardial ischemia-reperfusion injury, monocytes enter the heart and differentiate into diverse subpopulations of macrophages. Here we show that deletion of Hif1α, a hypoxia response transcription factor, in resident cardiac macrophages led to increased remodeling and overrepresentation of macrophages expressing arginase 1 (Arg1).

GPC3-mediated metabolic rewiring of diabetic mesenchymal stromal cells enhances their cardioprotective functions via PKM2 activation.

Mesenchymal stromal cells (MSC) are promising stem cell therapy for treating cardiovascular and other degenerative diseases. Diabetes affects the functional capability of MSC and impedes cell-based therapy. Despite numerous studies, the impact of diabetes on MSC myocardial reparative activity, metabolic fingerprint, and the mechanism of dysfunction remains inadequately perceived.

Phosphorylation of CRYAB Induces a Condensatopathy to Worsen Post-Myocardial Infarction Left Ventricular Remodeling.

Protein aggregates are emerging therapeutic targets in rare monogenic causes of cardiomyopathy and amyloid heart disease, but their role in more prevalent heart failure syndromes remains mechanistically unexamined. We observed mis-localization of desmin and sarcomeric proteins to aggregates in human myocardium with ischemic cardiomyopathy and in mouse hearts with post-myocardial infarction ventricular remodeling, mimicking findings of autosomal-dominant cardiomyopathy induced by R120G mutation in the cognate chaperone protein, CRYAB. In both syndromes, we demonstrate increased partitioning of CRYAB phosphorylated on serine-59 to NP40-insoluble aggregate-rich biochemical fraction.