Postoperative placement of an anti-fibrotic poly L-lactide electrospun fibrous membrane after sinus surgery.

Background: Endoscopic sinus surgery (ESS) is used to treat chronic rhinosinusitis. However, nasal adhesions often develop postoperatively, triggered by chronic inflammation and local fibrosis. A poly L-lactide (PLLA) electrospun microfibrous membrane is a functional biodegradable material that can be placed on the wound surface to protect the wound and prevent adhesions.

Methods: We divided 24 rabbits randomly into 2 groups, a control operation group (group A) and an operation+PLLA placement group (group B). We investigated the anti-fibrotic effects of the topical biomaterial after sinus surgery. We placed PLLA fibrous membranes in the sinus cavity of group B rabbits after sinus surgery, and then evaluated changes in the mucosa and in the levels of collagen fibers, interleukin 4 (IL-4), IL-8, tumor necrosis factor α (TNF-α), transforming growth factor β1 (TGF-β1), α-smooth muscle actin (α-SMA), and collagen I (Col I), using morphological and molecular biological methods.

Results: PLLA fibrous membranes did not inhibit the synthesis of messenger RNAs (mRNAs) encoding IL-4, IL-8, or TNF-α, or the protein levels, indicating that the membrane did not have an anti-inflammatory effect. However, the membrane inhibited the synthesis of mRNAs encoding TGF-β1, α-SMA, and Col I, and reduced collagen production. Thus, the nanostructured membrane inhibited fibroblast proliferation.

Conclusion: The PLLA membrane had anti-fibrotic effects, and may be used to prevent fibrosis and adhesions after ESS in human patients.