Changes in glomerular parietal epithelial cells in mouse kidneys with advanced age

Area of Science:

• Nephrology
• Gerontology
• Cell Biology

Background:

• Kidney aging involves glomerular changes, but effects on parietal epithelial cells (PECs) are unclear.
• It's unknown if aging patterns in human/rat glomeruli occur in aged mice.

Purpose of the Study:

• To investigate the impact of aging on glomerular PECs in aged mice.
• To determine if aged mice exhibit similar glomerular changes as aged humans and rats.

Main Methods:

• Descriptive analysis of glomeruli from young (3-mo) and aged (27-mo) C57B6 mice.
• Immunohistochemical staining for PEC density, matrix proteins, CD44, phosphorylated ERK, EMT markers, and mural cell markers.

Main Results:

• Aged mice showed significantly lower PEC density, particularly in juxtamedullary glomeruli.
• Increased collagen IV, heparan sulfate proteoglycan, and de novo CD44 expression in aged glomeruli.
• Aged PECs expressed α-smooth muscle, vimentin, neural/glial antigen 2, PDGF receptor-β, CD146, and Notch 3, indicating activation and mural cell phenotype.

Conclusions:

• Aged mice are a suitable model for studying kidney aging.
• PECs undergo significant age-related changes, particularly in juxtamedullary glomeruli.
• These PEC alterations may contribute to age-related decline in kidney structure and function.