mTORC1 activation in podocytes is a critical step in the development of diabetic nephropathy in mice

Ken Inoki, Hiroyuki Mori, Junying Wang, Tsukasa Suzuki, SungKi Hong, Sei Yoshida, Simone M. Blattner, Tsuneo Ikenoue, Markus A. Rüegg, Michael N. Hall, David J. Kwiatkowski, Maria P. Rastaldi, Tobias B. Huber, Matthias Kretzler, Lawrence B. Holzman, Roger C. Wiggins, Kun Liang Guan

Research output: Contribution to journalArticle

Abstract

Diabetic nephropathy (DN) is among the most lethal complications that occur in type 1 and type 2 diabetics. Podocyte dysfunction is postulated to be a critical event associated with proteinuria and glomerulosclerosis in glomerular diseases including DN. However, molecular mechanisms of podocyte dysfunction in the development of DN are not well understood. Here we have shown that activity of mTOR complex 1 (mTORC1), a kinase that senses nutrient availability, was enhanced in the podocytes of diabetic animals. Further, podocytespecific mTORC1 activation induced by ablation of an upstream negative regulator (PcKOTsc1) recapitulated many DN features, including podocyte loss, glomerular basement membrane thickening, mesangial expansion, and proteinuria in nondiabetic young and adult mice. Abnormal mTORC1 activation caused mislocalization of slit diaphragm proteins and induced an epithelial-mesenchymal transition-like phenotypic switch with enhanced ER stress in podocytes. Conversely, reduction of ER stress with a chemical chaperone significantly protected against both the podocyte phenotypic switch and podocyte loss in PcKOTsc1 mice. Finally, genetic reduction of podocyte-specific mTORC1 in diabetic animals suppressed the development of DN. These results indicate that mTORC1 activation in podocytes is a critical event in inducing DN and suggest that reduction of podocyte mTORC1 activity is a potential therapeutic strategy to prevent DN.

Original languageEnglish
Pages (from-to)2181-2196
Number of pages16
JournalJournal of Clinical Investigation
Volume121
Issue number6
DOIs
Publication statusPublished - Jun 1 2011

ASJC Scopus subject areas

  • Medicine(all)

Fingerprint Dive into the research topics of 'mTORC1 activation in podocytes is a critical step in the development of diabetic nephropathy in mice'. Together they form a unique fingerprint.

  • Cite this

    Inoki, K., Mori, H., Wang, J., Suzuki, T., Hong, S., Yoshida, S., Blattner, S. M., Ikenoue, T., Rüegg, M. A., Hall, M. N., Kwiatkowski, D. J., Rastaldi, M. P., Huber, T. B., Kretzler, M., Holzman, L. B., Wiggins, R. C., & Guan, K. L. (2011). mTORC1 activation in podocytes is a critical step in the development of diabetic nephropathy in mice. Journal of Clinical Investigation, 121(6), 2181-2196. https://doi.org/10.1172/JCI44771