Peripheral glucocorticoid receptor antagonism by relacorilant with modest HPA axis disinhibition

Glucocorticoid stress hormones are produced in response to hypothalamic-pituitary-adrenal (HPA) axis activation. Glucocorticoids are essential for physiology and exert numerous actions via binding to the glucocorticoid receptor (GR). Relacorilant is a highly selective GR antagonist currently undergoing a phase 3 clinical evaluation for the treatment of endogenous Cushing's syndrome. It was found that increases in serum adrenocorticotropic hormone (ACTH) and cortisol concentrations after relacorilant treatment were substantially less than the increases typically observed with mifepristone, but it is unclear what underlies these differences. In this study, we set out to further preclinically characterize relacorilant in comparison to the classical but non-selective GR antagonist mifepristone. In human HEK-293 cells, relacorilant potently antagonized dexamethasone- and cortisol-induced GR signaling, and in human peripheral blood mononuclear cells, relacorilant largely prevented the anti-inflammatory effects of dexamethasone. In mice, relacorilant treatment prevented hyperinsulinemia and immunosuppression caused by increased corticosterone exposure. Relacorilant treatment reduced the expression of classical GR target genes in peripheral tissues but not in the brain. In mice, relacorilant induced a modest disinhibition of the HPA axis as compared to mifepristone. In line with this, in mouse pituitary cells, relacorilant was generally less potent than mifepristone in regulating Pomc mRNA and ACTH release. This contrast between relacorilant and mifepristone is possibly due to the distinct transcriptional coregulator recruitment by the GR. In conclusion, relacorilant is thus an efficacious peripheral GR antagonist in mice with only modest disinhibition of the HPA axis, and the distinct properties of relacorilant endorse the potential of selective GR antagonist treatment for endogenous Cushing's syndrome.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:256

Enthalten in:

The Journal of endocrinology - 256(2023), 2 vom: 01. Feb.

Sprache:

Englisch

Beteiligte Personen:

Viho, Eva M G [VerfasserIn]
Kroon, Jan [VerfasserIn]
Feelders, Richard A [VerfasserIn]
Houtman, René [VerfasserIn]
van den Dungen, Elisabeth S R [VerfasserIn]
Pereira, Alberto M [VerfasserIn]
Hunt, Hazel J [VerfasserIn]
Hofland, Leo J [VerfasserIn]
Meijer, Onno C [VerfasserIn]

Links:

Volltext

Themen:

2158753C7E
320T6RNW1F
7S5I7G3JQL
9002-60-2
Adrenocorticotropic Hormone
Cushing’s syndrome
Dexamethasone
Glucocorticoid receptor
Glucocorticoids
HPA axis
Hydrocortisone
Journal Article
Mifepristone
Pituitary
Receptors, Glucocorticoid
Relacorilant
Research Support, Non-U.S. Gov't
WI4X0X7BPJ

Anmerkungen:

Date Completed 23.12.2022

Date Revised 31.03.2023

published: Electronic-Print

Citation Status MEDLINE

doi:

10.1530/JOE-22-0263

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM349581037