Circulating miRs-183-5p, -206-3p and -381-3p may serve as novel biomarkers for 4,4’-methylene diphenyl diisocyanate exposure

Background: Occupational exposure to the most widely used diisocyanate, 4,4’-methylene diphenyl diisocyanate (MDI), is a cause of occupational asthma (OA). Early recognition of MDI exposure and sensitization is essential for the prevention of MDI-OA. Objective: Identify circulating microRNAs (miRs) as novel biomarkers for early detection of MDI exposure and prevention of MDI-OA. Materials and methods: Female BALB/c mice were exposed to one of three exposure regimens: dermal exposure to 1% MDI in acetone; nose-only exposure to 4580 ± 1497 μg/m3 MDI-aerosol for 60 minutes; or MDI dermal exposure/sensitization followed by MDI-aerosol inhalation challenge. Blood was collected and miRCURY™ miRs qPCR Profiling Service was used to profile circulate miRs from dermally exposed mice. Candidate miRs were identified and verified from mice exposed to three MDI-exposure regimens by TaqMan® miR assays. Results: Up/down-regulation patterns of circulating mmu-miRs-183-5p, -206-3p and -381-3p were identified and verified. Circulating mmu-miR-183-5p was upregulated whereas mmu-miRs-206-3p and -381-3p were downregulated in mice exposed via all three MDI exposure regimens. Discussion and conclusion: Upregulation of circulating miR-183-5p along with downregulation of circulating miRs-206-3p and -381-3p may serve as putative biomarkers of MDI exposure and may be considered as potential candidates for validation in exposed human worker populations.