Increased Levels of BAMBI Inhibit Canonical TGF-β Signaling in Chronic Wound Tissues

Area of Science:

• Biomedical Science
• Wound Healing Research
• Cellular Biology

Background:

• Chronic wounds affect over 2% of the global population, imposing a significant healthcare burden.
• Transforming growth factor beta (TGF-β) is a critical regulator of inflammation, extracellular matrix (ECM) formation, and revascularization in wound healing.
• Understanding disturbances in chronic wound healing is crucial for developing effective treatments.

Purpose of the Study:

• To characterize molecular differences in acute versus chronic wound tissues.
• To investigate the role of TGF-β signaling and its regulators in chronic wound pathophysiology.
• To identify potential therapeutic targets for chronic wound management.

Main Methods:

• Analysis of serum and tissue samples from 38 patients (20 acute, 18 chronic wounds).
• Measurement of angiogenesis, inflammation, ECM formation/degradation markers, and TGF-β signaling components.
• Utilized techniques including Western blots, immunostaining, reporter assays, and proteome profiler arrays.

Main Results:

• Chronic wounds exhibited increased MMP9 levels and activated TGF-β, but lacked TGF-β target gene regulation.
• Despite increased TGF-β1 and TGF-β3 expression, canonical TGF-β signaling was reduced in chronic wounds, suggesting an inhibitor.
• Elevated levels of the TGF-β pseudo-receptor BAMBI were found in chronic wound tissues (10.6-fold increase) and wounds that became chronic (9.5-fold increase).

Conclusions:

• BAMBI may play a regulatory role in the development of chronic wounds.
• Increased BAMBI expression is observed in both chronic wounds and acute wounds progressing to chronicity.
• BAMBI presents a potential therapeutic target for controlling scar formation and improving chronic wound healing.