Bromhexine elevates REP2 expression to stimulate secretion from human primary conjunctiva fornix epithelial cells

Area of Science:

• Ophthalmology
• Cell Biology
• Pharmacology

Background:

• Bromhexine has shown potential in alleviating early-stage Sjogren Syndrome symptoms.
• The precise mechanism of bromhexine's action in ocular tissues is not fully understood.

Purpose of the Study:

• To investigate the cellular mechanisms by which low-dose bromhexine affects human primary conjunctival fornix epithelial cells.
• To explore bromhexine's potential as a therapeutic agent for dry eye disease.

Main Methods:

• Treatment of human primary conjunctival fornix epithelial cells with low-dose bromhexine.
• Analysis of MUC5AC secretion and lipid droplet production.
• Assessment of gene and protein expression, specifically focusing on CHML and REP2.

Main Results:

• Bromhexine treatment significantly stimulated MUC5AC secretion.
• Increased lipid droplet production was observed in the treated cells.
• Bromhexine upregulated the expression of the metabolism-related gene CHML, leading to the induction of its protein product, REP2.

Conclusions:

• Bromhexine promotes key factors involved in ocular surface health, such as MUC5AC secretion.
• The findings indicate that bromhexine may be a promising candidate for eye drop formulations.
• Bromhexine's therapeutic potential extends to various forms of dry eye disease beyond Sjogren Syndrome.