Secretory products from regulatory macrophages modulate senescence in human endothelial cells: implications for cardiovascular aging and diseases

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide and primarily affect older individuals, making CVDs a central concern in age-related and geriatric medicine. Senescent endothelial cells contribute to a pro-inflammatory environment that exacerbates cardiovascular pathology. Therapies targeting senescent cells, hold promise for treating/preventing CVDs and anti-inflammatory regulatory macrophages (Mreg) may represent a novel cell-based therapeutic approach. Here we investigated the impact of Mreg secretory products (SPMreg) on the early and late passage phenotype of human endothelial cells (HUVEC, human umbilical vein endothelial cells), with implications for cardiovascular aging and diseases. HUVEC were classified as early passage (HUVECep, passages 4–6) or late passage (HUVEClp, passages 10–13) and cultured for 10 days with or without SPMreg. Parameters associated with endothelial aging, including cell morphology, size and volume, β-galactosidase activity, CD105 expression, reactive oxygen species (ROS), and senescence-associated secretory phenotype (SASP) factor release, were analyzed. HUVECep exhibited a typical cobblestone-like morphology, whereas HUVEClp displayed a spindle-shaped appearance. Both cell types showed an elongated, fibroblast-like cell type after incubation with SPMreg. In HUVEClp, treatment with SPMreg significantly reduced cell size and volume at all time points (P < 0.05). In HUVECep, SPMreg increased β-galactosidase activity and the proportion of ROS-positive cells, while reducing secretion of the SASP factor PAI-1 (P < 0.05 for all). In HUVEClp SPMreg increased β-galactosidase activity, attenuated the time-dependent increase of ROS levels and secretion of SASP factor Activin A (P < 0.05 for all). Our findings demonstrate that SPMreg modulate several factors associated with endothelial senescence, highlighting a potential role for Mreg in processes related to cardiovascular aging.