Fibrosis-Related Gene and Protein Expression in Normal and Glaucomatous Trabecular Meshwork Cells.

Area of Science:

• Ophthalmology
• Cell Biology
• Biochemistry

Background:

• Glaucomatous trabecular meshwork (GTM) exhibits excessive fibrotic extracellular matrices, impairing aqueous humor outflow.
• Endothelial-to-mesenchymal transition (EndMT) is a key process implicated in tissue fibrosis.

Purpose of the Study:

• To investigate the fibrotic gene and protein profiles of GTM cells compared to non-glaucomatous trabecular meshwork (NTM) cells.
• To determine if GTM cells exhibit characteristics of EndMT.

Main Methods:

• Primary NTM and GTM cells were cultured from human cadaver eyes.
• mRNA profiling using the human fibrosis panel (NanoString), quantitative PCR (qPCR), and Western blotting were performed.
• Matrix metalloproteinase (MMP) activity was assessed using a fluorogenic assay.

Main Results:

• GTM cells showed upregulated EndMT biomarkers (α-SMA, SNAI2, TWISTs, VIM) and increased TGFβ signaling.
• Increased deposition of fibronectin EDA (FN-EDA) and altered integrin expression were observed in GTM cells.
• GTM cells exhibited decreased levels of MMP2, CHI3L1, COL6A3, SERPINF1 proteins but increased MMP activity.

Conclusions:

• Upregulated EndMT markers and altered extracellular matrix components suggest GTM cells undergo EndMT.
• Cultured GTM cells represent a relevant in vitro model for investigating glaucoma-associated fibrosis.