Cyanidin-3-glucoside Ameliorates Ocular Surface Dysfunction in Rats with Dry Eye Disease

Abstract:

[Objective]Studies have shown that cyanidin-3-glucoside (C3G), the main component of black rice anthocyanins, exhibits protective effects on retina and retinal pigment epithelium (RPE) cells. However, there is a lack of in vivo evidence regarding the efficacy of C3G in alleviating dry eye disease (DED), which limits its application in ocular surface disorders. This study aims to investigate the protective effects of C3G on DED in rats.[Method]24 Wistar rats were randomly assigned into control, model, and C3G groups. In model and C3G groups, a DED model was established by subcutaneous injection of scopolamine hydrobromide (4 times daily for 28 d). The C3G group was administered 50 mg/kg C3G by gavage during the modeling period. DED parameters, including tear secretion and fluorescein sodium staining, were measured weekly. On day 28, corneal and conjunctival tissue samples were collected to assess inflammatory cytokine levels and histopathological changes.[Result]Compared with the control group, the model group showed reduced tear secretion, increased corneal fluorescein staining scores, upregulated mRNA relative expression levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) genes(P<0.05), disarrangement of corneal cells, loose stromal layers, and decreased goblet cells in the conjunctival tissue. Compared with the model group, the C3G group showed elevated tear secretion, reduced fluorescein staining scores, downregulated mRNA relative expression levels of TNF-α and IL-6 genes (P<0.05), tightly arranged corneal cells and increased goblet cells in the conjunctival tissue.[Conclusion]C3G has the effect of alleviating corneal and conjunctival tissue damage in DED rats, which provides a theoretical basis for the development of functional food containing black rice anthocyanins for eye protection.