Inhibition of microRNA-328 Increases Ocular Mucin Expression and Conjunctival Goblet Cells

Area of Science:

• Ophthalmology
• Molecular Biology
• MicroRNA Therapeutics

Background:

• Dry eye disease (DED) is often associated with decreased mucin secretion.
• MicroRNAs (miRNAs) play a role in regulating cellular processes relevant to DED.
• Previous work established anti-microRNA-328 (anti-miR-328) as a potential therapy for DED.

Purpose of the Study:

• To investigate the effect of anti-miR-328 on mucin expression and goblet cell function in DED.
• To elucidate the molecular mechanism by which anti-miR-328 influences mucin production.

Main Methods:

• Bioinformatic analysis to predict miR-328 targets.
• In vitro assays including transfection, luciferase reporter assays, qPCR, Western blot, and ELISA.
• In vivo studies using impression cytology in a rabbit model of DED induced by benzalkonium chloride (BAC).

Main Results:

• miR-328 levels were elevated in goblet cells under desiccating stress or BAC treatment.
• miR-328 was confirmed to target and inhibit the transcription factor CREB1.
• Anti-miR-328 treatment increased CREB1 and Mucin 5AC (MUC5AC) expression and secretion in cultured goblet cells.
• Anti-miR-328 therapy increased goblet cell numbers in the conjunctiva of DED rabbits.

Conclusions:

• Anti-miR-328 therapy enhances CREB1 expression, leading to increased MUC5AC production and secretion.
• Anti-miR-328 therapy also promotes an increase in conjunctival goblet cell numbers.
• These findings support the further development of anti-miR-328 as a therapeutic strategy for dry eye disease.