SCARB1 downregulation in adrenal insufficiency with Allgrove syndrome

Orphanet J Rare Dis. 2023 Jun 19;18(1):152. doi: 10.1186/s13023-023-02763-w.

Abstract

Background: Allgrove disease is a rare genetic syndrome characterized by adrenal insufficiency, alacrimia, achalasia and complex neurological involvement. Allgrove disease is due to recessive mutations in the AAAS gene, which encodes for the nucleoporin Aladin, implicated in the nucleocytoplasmic transport. The adrenal insufficiency has been suggested to rely on adrenal gland-ACTH resistance. However, the link between the molecular pathology affecting the nucleoporin Aladin and the glucocorticoid deficiency is still unknown.

Results: By analyzing postmortem patient's adrenal gland, we identified a downregulation of Aladin transcript and protein. We found a downregulation of Scavenger receptor class B-1 (SCARB1), a key component of the steroidogenic pathway, and SCARB1 regulatory miRNAs (mir125a, mir455) in patient's tissues. With the hypothesis of an impairment in the nucleocytoplasmic transport of the SCARB1 transcription enhancer cyclic AMP-dependent protein kinase (PKA), we detected a reduction of nuclear Phospho-PKA and a cytoplasmic mislocalization in patient's samples.

Conclusions: These results shed a light on the possible mechanisms linking ACTH resistance, SCARB1 impairment, and defective nucleocytoplasmic transport.

Keywords: Adrenal cortex; Adrenal insufficiency; Allgrove syndrome; PKA; SCARB1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Insufficiency* / genetics
  • Adrenal Insufficiency* / metabolism
  • Adrenal Insufficiency* / pathology
  • Down-Regulation / genetics
  • Esophageal Achalasia* / genetics
  • Esophageal Achalasia* / metabolism
  • Esophageal Achalasia* / pathology
  • Humans
  • MicroRNAs*
  • Nerve Tissue Proteins / genetics
  • Nuclear Pore Complex Proteins / genetics
  • Nuclear Pore Complex Proteins / metabolism
  • Nuclear Proteins / genetics
  • Scavenger Receptors, Class B / genetics
  • Scavenger Receptors, Class B / metabolism

Substances

  • Nuclear Pore Complex Proteins
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • SCARB1 protein, human
  • Scavenger Receptors, Class B
  • MIRN455 microRNA, human
  • MicroRNAs

Supplementary concepts

  • Familial Glucocorticoid Deficiency 1
  • Achalasia Addisonianism Alacrimia syndrome