Serum microRNAs in Systemic Sclerosis, Associations with Digital Vasculopathy and Lung Involvement

Area of Science:

• Immunology
• Genetics
• Biochemistry

Background:

• Systemic sclerosis (SSc) is a rare, multisystem autoimmune disease with unclear etiology.
• Epigenetic mechanisms, particularly circulating microRNAs, are increasingly implicated in SSc pathogenesis.
• MicroRNAs play a role in regulating Toll-like receptor (TLR) pathways and maintaining autoimmune balance.

Purpose of the Study:

• To investigate the expression profiles of selected circulating microRNAs (miR-126, -132, -143, -145, -155, -181a, -29a, -3148) in patients with Systemic Sclerosis (SSc) compared to healthy controls.
• To analyze microRNA expression in relation to SSc subtypes (diffuse and limited) and clinical parameters.

Main Methods:

• Serum samples were collected from 45 SSc patients and 57 healthy controls (HC).
• Expression levels of eight specific microRNAs were quantified.
• SSc patients were subcategorized into diffuse systemic sclerosis (dcSSc) and limited systemic sclerosis (lcSSc).

Main Results:

• Most analyzed microRNAs, except miR-126, miR-29a, and miR-181a, were significantly upregulated in SSc patients versus HC.
• miR-181a was detected only in limited SSc (lcSSc) patients.
• Correlations were observed between miR-143 and forced vital capacity (FVC), and between miR-126/miR-145 and carbon monoxide transfer factor (TLCO).
• miR-132 expression was higher in dcSSc with active lung lesions, and miR-155 was higher in early microangiopathy patterns.

Conclusions:

• Circulating cell-free microRNA expression profiles are significantly altered in SSc patients.
• Downregulation of miR-181a and overexpression of miR-132, miR-143, miR-145, and miR-155 may hold significance as potential biomarkers for SSc.