Abstract
Purpose :
Inflammation-driven scarring is associated with high rates of surgical failure in trabeculectomies and in minimally invasive glaucoma procedures alike. The current gold standard anti-scarring adjuvant mitomycin C (MMC) has variable effectiveness in controlling fibroproliferation and is associated with significant cytotoxic effects. Acetylsalicylic acid (ASA) is unique among non-steroidal anti-inflammatory drugs, exerting its effects through covalent enzyme modifications. When delivered locally, ASA repurposes the typically pro-inflammatory cyclooxygenase (COX-2) enzyme to resolve inflammation, rather than simply suppressing it. By resolving inflammation, it reduces likelihood of inflammation-mediated fibroproliferation and fibrosis.
The aim of this study is to determine whether ASA decreases inflammatory cytokine-induced scarring activity in human Tenon’s capsule fibroblasts (HTCFs) and to compare the effects of ASA to MMC in in vitro model of subconjunctival scarring.
Methods :
Glaucoma patient-derived HTCFs in 2D and 3D models were co-treated with inflammatory cytokine TGFβ1 with and without ASA (concentrations ranging 100-1600µg/ml), or MMC (0.05-0.2mg/mL), to assess their effects on HTCF activity via Western Blot, immunofluorescence, MTT, LDH and 3D collagen contraction assays. ASA-triggered lipid mediators were measured using liquid chromatography tandem mass spectrometry (LC-MS/MS).
Results :
ASA treatment decreased HTCF-mediated collagen contraction, TGFβ1-induced HTCF metabolic activity, and myofibroblast-associated protein expression, in the absence of cell necrosis. In comparison to MMC, ASA was as effective in reducing markers of inflammation and scarring, while being less cytotoxic.
Within cytokine-activated HTCFs, ASA significantly impaired prostaglandin production and significantly increased secretion of the pro-resolving lipid mediators 5-hydroxyeicosatetraenoic acid (HETE), 15-HETE and 18-hydroxyeicosapentaenoic acid (HEPE).
Conclusions :
ASA reduces cytokine-induced myofibroblast transdifferentiation in human Tenon’s capsule fibroblasts, being non-inferior to MMC in vitro. ASA’s unique effects are associated with unique lipid mediator expression profile. ASA-driven resolution of inflammation may be a promising strategy to mitigate cellular events associated with cytokine-mediated scarring.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.