Over-expression of a retinol dehydrogenase (SRP35/DHRS7C) in skeletal muscle activates mTORC2, enhances glucose metabolism and muscle performance

Sci Rep. 2018 Jan 12;8(1):636. doi: 10.1038/s41598-017-18844-3.

Abstract

SRP-35 is a short-chain dehydrogenase/reductase belonging to the DHRS7C dehydrogenase/ reductase family 7. Here we show that its over-expression in mouse skeletal muscles induces enhanced muscle performance in vivo, which is not related to alterations in excitation-contraction coupling but rather linked to enhanced glucose metabolism. Over-expression of SRP-35 causes increased phosphorylation of AktS473, triggering plasmalemmal targeting of GLUT4 and higher glucose uptake into muscles. SRP-35 signaling involves RARα and RARγ (non-genomic effect), PI3K and mTORC2. We also demonstrate that all-trans retinoic acid, a downstream product of the enzymatic activity of SRP-35, mimics the effect of SRP-35 in skeletal muscle, inducing a synergistic effect with insulin on AKTS473 phosphorylation. These results indicate that SRP-35 affects skeletal muscle metabolism and may represent an important target for the treatment of metabolic diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Gene Expression
  • Glucose / metabolism*
  • Glucose Transporter Type 4 / metabolism
  • MAP Kinase Signaling System
  • Male
  • Mechanistic Target of Rapamycin Complex 2 / metabolism*
  • Mice
  • Mice, Transgenic
  • Muscle, Skeletal / physiology*
  • Oxidoreductases / genetics*
  • Oxidoreductases / metabolism*
  • Phosphorylation
  • Receptors, Retinoic Acid
  • Retinoic Acid Receptor alpha / metabolism

Substances

  • Glucose Transporter Type 4
  • Rara protein, mouse
  • Receptors, Retinoic Acid
  • Retinoic Acid Receptor alpha
  • Slc2a4 protein, mouse
  • retinoic acid receptor beta
  • DHRS7C protein, mouse
  • Oxidoreductases
  • Mechanistic Target of Rapamycin Complex 2
  • Glucose