Deficiency of ALADIN impairs redox homeostasis in human adrenal cells and inhibits steroidogenesis.

Abstract:

UNLABELLED:Triple A syndrome is a rare, autosomal recessive cause of adrenal failure. Additional features include alacrima, achalasia of the esophageal cardia, and progressive neurodegenerative disease. The AAAS gene product is the nuclear pore complex protein alacrima-achalasia-adrenal insufficiency neurological disorder (ALADIN), of unknown function. Triple A syndrome patient dermal fibroblasts appear to be more sensitive to oxidative stress than wild-type fibroblasts. To provide an adrenal and neuronal-specific disease model, we established AAAS-gene knockdown in H295R human adrenocortical tumor cells and SH-SY5Y human neuroblastoma cells by lentiviral short hairpin RNA transduction. AAAS-knockdown significantly reduced cell viability in H295R cells. This effect was exacerbated by hydrogen peroxide treatment and improved by application of the antioxidant N-acetylcysteine. An imbalance in redox homeostasis after AAAS knockdown was further suggested in the H295R cells by a decrease in the ratio of reduced to oxidized glutathione. AAAS-knockdown SH-SY5Y cells were also hypersensitive to oxidative stress and responded to antioxidant treatment. A further impact on function was observed in the AAAS-knockdown H295R cells with reduced expression of key components of the steroidogenic pathway, including steroidogenic acute regulatory and P450c11β protein expression. Importantly a significant reduction in cortisol production was demonstrated with AAAS knockdown, which was partially reversed with N-acetylcysteine treatment. CONCLUSION:Our in vitro data in AAAS-knockdown adrenal and neuronal cells not only corroborates previous studies implicating oxidative stress in this disorder but also provides further insights into the pathogenic mechanisms in triple A syndrome.

journal_name

Endocrinology

journal_title

Endocrinology

authors

Prasad R,Metherell LA,Clark AJ,Storr HL

doi

10.1210/en.2013-1241

subject

Has Abstract

pub_date

2013-09-01 00:00:00

pages

3209-18

issue

9

eissn

0013-7227

issn

1945-7170

pii

en.2013-1241

journal_volume

154

pub_type

杂志文章