The consequences of increased 4E-BP1 in polycystic kidney disease

Abstract

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary renal disease, characterized by cyst formation and growth. Hyperproliferation is a major contributor to cyst growth. At the nexus of regulating proliferation, is 4E-BP1. We demonstrate that ADPKD mouse and rat models, ADPKD patient renal biopsies and PKD1−/− cells exhibited hyperphosphorylated 4E-BP1, a biomarker of increased translation and proliferation. We hypothesized that expression of constitutively active 4E-BP1 constructs (4E-BP1F113A and 4E-BP1R13AF113A) would decrease proliferation and reduce cyst expansion. Utilizing the Pkd1RC/RC mouse, we determined the effect of 4E-BP1F113A on PKD. Unexpectedly, 4E-BP1F113A resulted in increased cyst burden and suppressed apoptosis markers, increased anti-apoptotic Bcl-2 protein and increased mitochondrial proteins. Exogenous 4E-BP1 enhanced proliferation, decreased apoptosis, increased anti-apoptotic Bcl-2 protein, impaired NADPH oxidoreductase activity, increased mitochondrial proteins and increased superoxide production in PKD patient-derived renal epithelial cells. Reduced 4E-BP1 expression suppressed proliferation, restored apoptosis and improved cellular metabolism. These findings provide insight into how cyst-lining cells respond to 4E-BP1.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 19, 2019
Source ID
10.1093/hmg/ddz244

Entities

People

  • Andrew M. Lombardi
  • Carolyn N. Brown
  • Charles L. Edelstein
  • Daniel J. Atwood
  • Deepak Pokhrel
  • Katharina Hopp
  • Khoa N. Nguyen
  • Mary C M Weiser-evans
  • Miguel Lanaspa
  • Ryan C Hill
  • Sara E Brown
  • Sara J. Holditch

Organizations

  • National Institutes of Health
  • Polycystic Kidney Disease Foundation
  • United States Department of Defense
  • United States Department of Veterans Affairs
  • University of Colorado
  • University of Colorado Denver

Tags

Fields of Study

  • Biology

Readers

  • Cellular and Molecular Pathways of Apoptosis.
  • Molecular and Cellular Biology