Unraveling the role of podocyte turnover in glomerular aging and injury

TY - JOUR

T1 - Unraveling the role of podocyte turnover in glomerular aging and injury

AU - Wanner, Nicola

AU - Hartleben, Björn

AU - Herbach, Nadja

AU - Goedel, Markus

AU - Stickel, Natalie

AU - Zeiser, Robert

AU - Walz, Gerd

AU - Moeller, Marcus J

AU - Grahammer, Florian

AU - Huber, Tobias B

PY - 2014/4

Y1 - 2014/4

N2 - Podocyte loss is a major determinant of progressive CKD. Although recent studies showed that a subset of parietal epithelial cells can serve as podocyte progenitors, the role of podocyte turnover and regeneration in repair, aging, and nephron loss remains unclear. Here, we combined genetic fate mapping with highly efficient podocyte isolation protocols to precisely quantify podocyte turnover and regeneration. We demonstrate that parietal epithelial cells can give rise to fully differentiated visceral epithelial cells indistinguishable from resident podocytes and that limited podocyte renewal occurs in a diphtheria toxin model of acute podocyte ablation. In contrast, the compensatory programs initiated in response to nephron loss evoke glomerular hypertrophy, but not de novo podocyte generation. In addition, no turnover of podocytes could be detected in aging mice under physiologic conditions. In the absence of podocyte replacement, characteristic features of aging mouse kidneys included progressive accumulation of oxidized proteins, deposits of protein aggregates, loss of podocytes, and glomerulosclerosis. In summary, quantitative investigation of podocyte regeneration in vivo provides novel insights into the mechanism and capacity of podocyte turnover and regeneration in mice. Our data reveal that podocyte generation is mainly confined to glomerular development and may occur after acute glomerular injury, but it fails to regenerate podocytes in aging kidneys or in response to nephron loss.

AB - Podocyte loss is a major determinant of progressive CKD. Although recent studies showed that a subset of parietal epithelial cells can serve as podocyte progenitors, the role of podocyte turnover and regeneration in repair, aging, and nephron loss remains unclear. Here, we combined genetic fate mapping with highly efficient podocyte isolation protocols to precisely quantify podocyte turnover and regeneration. We demonstrate that parietal epithelial cells can give rise to fully differentiated visceral epithelial cells indistinguishable from resident podocytes and that limited podocyte renewal occurs in a diphtheria toxin model of acute podocyte ablation. In contrast, the compensatory programs initiated in response to nephron loss evoke glomerular hypertrophy, but not de novo podocyte generation. In addition, no turnover of podocytes could be detected in aging mice under physiologic conditions. In the absence of podocyte replacement, characteristic features of aging mouse kidneys included progressive accumulation of oxidized proteins, deposits of protein aggregates, loss of podocytes, and glomerulosclerosis. In summary, quantitative investigation of podocyte regeneration in vivo provides novel insights into the mechanism and capacity of podocyte turnover and regeneration in mice. Our data reveal that podocyte generation is mainly confined to glomerular development and may occur after acute glomerular injury, but it fails to regenerate podocytes in aging kidneys or in response to nephron loss.

KW - Aging

KW - Animals

KW - Flow Cytometry

KW - Hypertrophy

KW - Kidney Glomerulus

KW - Mice

KW - Podocytes

KW - Regeneration

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1681/ASN.2013050452

DO - 10.1681/ASN.2013050452

M3 - SCORING: Journal article

C2 - 24408871

VL - 25

SP - 707

EP - 716

JO - J AM SOC NEPHROL

JF - J AM SOC NEPHROL

SN - 1046-6673

IS - 4

ER -