Extra-adrenal glucocorticoid biosynthesis: implications for autoimmune and inflammatory disorders

Area of Science:

• Endocrinology
• Immunology
• Molecular Biology

Background:

• Glucocorticoid synthesis is a multistep process initiated by cholesterol delivery to mitochondria.
• Enzymes like CYP11A1, 3-βHSD, CYP17A1, CYP21A2, and CYP11B1 are crucial for converting cholesterol to cortisol.
• Glucocorticoids regulate immune responses via the glucocorticoid receptor (GR).

Purpose of the Study:

• To review the role of extra-adrenal glucocorticoid production in autoimmune diseases.
• To highlight the significance of local glucocorticoid biosynthesis and bioavailability in disease pathogenesis.
• To explore potential therapeutic avenues targeting local glucocorticoid metabolism.

Main Methods:

• Literature review of glucocorticoid synthesis and its role in immune regulation.
• Analysis of evidence linking extra-adrenal glucocorticoid dysregulation to autoimmune conditions.
• Synthesis of current understanding on glucocorticoid bioavailability and its modulation.

Main Results:

• Glucocorticoids are produced not only in the adrenal gland but also in extra-adrenal tissues like the immune system, skin, and brain.
• Extra-adrenal glucocorticoid production is influenced by hormones (ACTH, CRH) and cytokines (IL-1, IL-6, TNFα).
• Dysregulation of extra-adrenal glucocorticoid production is associated with autoimmune diseases such as multiple sclerosis, lupus erythematosus, rheumatoid arthritis, psoriasis, and atopic dermatitis.

Conclusions:

• Local glucocorticoid production and its bioavailability are critical factors in autoimmune disease development.
• Understanding the dysregulation of extra-adrenal glucocorticoid synthesis offers potential for new therapeutic strategies.
• Targeting local glucocorticoid production and bioavailability may provide novel treatments for autoimmune disorders.