Systemic sclerosis and AHR: Shedding light on a hidden connections

Area of Science:

• Immunology
• Dermatology
• Molecular Biology

Background:

• Systemic sclerosis (SSc) is a severe autoimmune disorder characterized by fibrosis, inflammation, and vascular issues.
• Current understanding of SSc pathogenesis, particularly fibrogenesis and organ involvement, remains incomplete, limiting treatment options.
• The aryl hydrocarbon receptor (AHR) is a transcription factor implicated in immune responses, fibrosis, and drug metabolism, particularly in barrier tissues.

Purpose of the Study:

• To review the potential role of the aryl hydrocarbon receptor (AHR) in the pathogenesis of Systemic Sclerosis (SSc).
• To explore the dual role of AHR as a potential pro- and anti-fibrotic regulator in SSc.
• To discuss the therapeutic potential of targeting AHR for SSc treatment.

Main Methods:

• Literature review of AHR function in fibrosis, inflammation, and immune responses.
• Analysis of AHR expression and role in cutaneous cell populations.
• Examination of AHR's molecular mechanisms, including gene expression and signaling pathway interactions.

Main Results:

• AHR is highly expressed in skin cells and is crucial for skin homeostasis.
• AHR activation can influence fibrogenic pathways, including TGF-β and extracellular matrix remodeling.
• AHR exhibits context-dependent effects, acting as both a pro- and anti-fibrotic factor in SSc.

Conclusions:

• AHR's multifaceted role in SSc suggests it is a promising therapeutic target.
• Selective AHR modulation (agonists or antagonists) could restore immune and fibrotic balance in SSc.
• Targeting AHR may offer novel strategies to improve disease progression and patient outcomes in Systemic Sclerosis.