Anti‐inflammatory effect of mulberry anthocyanins on experimental dry eye

Abstract

Aims/Purpose: To investigate the anti‐inflammatory effects of mulberry anthocyanin on dry eye.Methods: HME‐DDS (Hot‐Melt Extrusion‐Drug Delivery System) was used to maximize the content of anthocyanin in mulberry. Experimental dry eye (EDE) was induced by topical 0.2% BAK (benzalkonium chloride) eye drops instilled twice a day for 1 week. The animals were randomly divided into those treated with and without the mulberry HME‐DDS products (10 g/kg/day). Ocular surface staining using fluorescein and Schirmer's test were performed. After 2 weeks of treatments, the animals were sacrificed, and tissues were harvested, and immunohistochemistry was performed to detect inflammatory response to compare with the control group.Results: After mulberry HME‐DDS treatments, the corneal staining score was significantly decreased compared to the untreated group (3.33 ± 0.83, 7.63 ± 1.00; p = 0.004). In addition, mulberry HME‐DDS treated group showed a significant increase in tear production compared with the untreated group (8.83 ± 2.29, 6.18 ± 2.44; p = 0.014). The mulberry HME‐DDS products decreased the expression of IL‐1, IL‐6 and IL‐17 in the cornea and lacrimal gland.Conclusions: Mulberry with HME‐DDS technology improved ocular surface findings and tear production. In addition, the mulberry HME‐DDS product reduced the expression of inflammatory cytokines in the cornea and lacrimal gland, and it was speculated that anthocyanins containing mulberry could improve clinical manifestations by suppressing inflammation.