SGK1 induces vascular smooth muscle cell calcification through NF-κB signaling

  • Jakob Voelkl
  • Trang Td Luong
  • Rashad Tuffaha
  • Katharina Musculus
  • Tilman Auer
  • Xiaoming Lian
  • Christoph Daniel
  • Daniel Zickler
  • Beate Boehme
  • Michael Sacherer
  • Bernhard Metzler
  • Dietmar Kuhl
  • Maik Gollasch
  • Kerstin Amann
  • Dominik N Müller
  • Burkert Pieske
  • Florian Lang
  • Ioana Alesutan

Abstract

Medial vascular calcification, associated with enhanced mortality in chronic kidney disease (CKD), is fostered by osteo-/chondrogenic transdifferentiation of vascular smooth muscle cells (VSMCs). Here, we describe that serum- and glucocorticoid-inducible kinase 1 (SGK1) was upregulated in VSMCs under calcifying conditions. In primary human aortic VSMCs, overexpression of constitutively active SGK1S422D, but not inactive SGK1K127N, upregulated osteo-/chondrogenic marker expression and activity, effects pointing to increased osteo-/chondrogenic transdifferentiation. SGK1S422D induced nuclear translocation and increased transcriptional activity of NF-κB. Silencing or pharmacological inhibition of IKK abrogated the osteoinductive effects of SGK1S422D. Genetic deficiency, silencing, and pharmacological inhibition of SGK1 dissipated phosphate-induced calcification and osteo-/chondrogenic transdifferentiation of VSMCs. Aortic calcification, stiffness, and osteo-/chondrogenic transdifferentiation in mice following cholecalciferol overload were strongly reduced by genetic knockout or pharmacological inhibition of Sgk1 by EMD638683. Similarly, Sgk1 deficiency blunted vascular calcification in apolipoprotein E-deficient mice after subtotal nephrectomy. Treatment of human aortic smooth muscle cells with serum from uremic patients induced osteo-/chondrogenic transdifferentiation, effects ameliorated by EMD638683. These observations identified SGK1 as a key regulator of vascular calcification. SGK1 promoted vascular calcification, at least partly, via NF-κB activation. Inhibition of SGK1 may, thus, reduce the burden of vascular calcification in CKD.

Bibliografische Daten

OriginalspracheEnglisch
ISSN0021-9738
DOIs
StatusVeröffentlicht - 02.07.2018
PubMed 29889103