Post-translational modifications (PTMs), such as O-GlcNAcylation and phosphorylation, are related to MR overactivation in diabetes and metabolic syndrome. Aldosterone binding promotes the proteasomal degradation of MR. Under conditions of high glucose, O-GlcNAcylation, and PKCβ-mediated MR phosphorylation are increased. Salt loading and oxidative stress also increase MR phosphorylation through the EGER/ERK pathway. PTMs inhibit ubiquitin attachment to the MR and interfere with the receptor’s aldosterone-induced proteasomal degradation. Consequently, they increase the sensitivity of the MR to aldosterone and exacerbate aldosterone-associated complications.
- Rie Jo
- Hiroshi Itoh
- Hirotaka Shibata