Figure 1. Cross-talk evolution between cardiomyocytes and cardiac stromal cell subsets during aging. During aging, cardiomyocytes and cardiac mesenchymal stromal cells (cMSC) acquire specific senescence associated secretory phenotypes (SASP) which promote age-related changes in the heart. Pro-angiogenic factors expressed by aged cMSCs increased frequencies of non-classical CD31+ cMSCs expressing endothelial related genes. SASP related pro-inflammatory mediators from cMSCs promote recruitment of monocyte-derived CCR2+ macrophages, with IL-1ß production re-enforcing cMSC senescence, cardiomyocyte hypertrophy and altered contractility. Concomitant acquisition of a non-conventional SASP by aged cardiomyocytes stimulates cardiomyocyte hypertrophy and myofibroblast activation.