Switch in Laminin β2 to Laminin β1 Isoforms During Aging Controls Endothelial Cell Functions—Brief Report

Objective—Endothelial cells play important roles in tissue homeostasis and vascularization, a function that is impaired by aging. Here, we aim to decipher the role of the microenvironment underlying the impairment of endothelial cell functions by aging. Approach and Results—RNA sequencing of isolated cardiac endothelial cells derived from young and 18-month-old mouse hearts revealed that aging affects the endothelial expression of genes encoding extracellular matrix proteins, specifically the laminin β1 (Lamb1) and laminin β2 (Lamb2) chains. Whereas Lamb1 was upregulated, Lamb2 was decreased in endothelial cells in old mice compared with young controls. A similar change in expression patterns was observed after induction of acute myocardial infarction. Mimicking aging and injury conditions by plating endothelial cells on laminin β1–containing laminin 411 matrix impaired endothelial cell adhesion, migration, and tube formation and augmented endothelial-to-mesenchymal transition and endothelial detachment c...