Metabolites and Metabolic Functional Changes-Potential Markers for Endothelial Cell Senescence

Accumulation of senescent endothelial cells (ECs) in vasculature represents a key step in the development of vascular aging and ensuing age-related diseases. Given that removal of senescent ECs may prevent disease and improve health and wellbeing, the discovery of novel biomarkers that effectively identify senescent cells is of particular importance. As crucial elements for biological pathways and reliable bioindicators of cellular processes, metabolites demand attention in this context. Using senescent human brain microvascular endothelial cells (HBMECs) displaying a secretory phenotype and significant morphological, nuclear, and enzymatic changes compared to their young counterparts, this study has shown that senescent HBMECs lose their endothelial characteristics as evidenced by the disappearance of CD31/PECAM-1 from interendothelial cell junctions. The metabolic profiling of young versus senescent HBMECs also indicates significant differences in glucose, glutamine, and fatty acid metabolism. The analysis of intracellular and secreted metabolites proposes L-proline, L-glutamate, NAD⁺, and taurine/hypotaurine pathway components as potential biomarkers. However, further studies are required to assess the value of these agents as potential biomarkers and therapeutic targets.