Aging and the kidney
Schematic proposal for changes in glomerular parietal epithelial cels (PECs) in mice with advanced age
In young mice, confluent PECs (blue color with green nuclei) attach to Bowman’s capsule. With advanced age, there is a decrease in
PEC density (most pronounced in juxta-medullary glomeruli). Of the remaining PECs, a subset become activated and express CD44
(red color), and are likely pro-fibrotic.
Another subset undergoes EMT (purple color). These events are temporally associated with enhanced ERK activation and Notch 3
expression, andlikely further contribute to extracellular matrix production by PECs. The combination of reduced PEC density along
with enhanced activation andpossible EMT limit the capacity for PECs to function as podocyte progenitors in aging and contribute