Abstract:

Methods SPF‑grade male C57BL/6J mice were randomly divided into a control group, model groups (1 h, 3 h, 6 h irradiation), and a 3 h formula intervention group (n=8). First, mice were exposed to blue light (467  nm LED, 5 000±200 lx) for 1, 3, and 6  h, respectively. Retinal histopathology and thickness were examined using hematoxylin‑eosin (HE) staining; serum malondialdehyde (MDA) and glutathione (GSH) levels were measured using commercial assay kits; and retinal inflammatory factor mRNA expression was assessed by RT‑qPCR. After confirming 3  h as the appropriate model, the compound formula (1 000 mg·kg⁻¹·d⁻¹) was administered by gavage for 14  days, followed by 3  h blue light irradiation, and the same indicators were evaluated. Results With prolonged irradiation time, the thickness of each retinal layer gradually decreased (P<0.01 to P<0.000 1) and cell arrangement became disordered; serum MDA levels progressively increased (P<0.01), while GSH levels gradually decreased (P<0.01). The mRNA expression of Interleukin-1 beta(IL-1β), Interleukin-6(IL-6), and Tumor Necrosis Factor-alpha(TNF-α) in retinal tissue was significantly upregulated with increasing irradiation time. The 1  h irradiation group showed only minor changes, whereas the 6 h irradiation group exhibited the most pronounced changes (P<0.000 1). Therefore, 3  h of blue light irradiation (P<0.001), which showed significant yet moderate differences in all indicators, was selected as the subsequent modeling condition. After formula intervention, compared with the model group, serum MDA level was significantly reduced (P<0.01), and serum GSH level was significantly increased (P<0.05). The expression levels of retinal inflammatory factors IL-1β (P<0.0001), IL-6 (P<0.001), and TNF-α (P<0.01) were significantly downregulated. Total retinal thickness (P<0.01), as well as the thicknesses of the inner plexiform layer (P<0.05), inner nuclear layer (P<0.05), outer plexiform layer (P<0.05), and outer nuclear layer (P<0.01), was significantly increased compared with the model group. Histopathological examination also showed that the regularity and density of retinal cell arrangement were markedly better than those in the model group. Conclusion Blue light irradiation at a specific intensity for 3  h can establish a stable mouse model of retinal injury. The compound formula alleviates retinal damage through antioxidant and anti-inflammatory pathways, providing an experimental basis for the development of related functional foods. Objective To investigate the time‑dependent pattern of blue light‑induced retinal damage in mice, establish a suitable animal model, and evaluate the protective effects of a compound formula containing lutein esters, DHA algal oil, Lycium ruthenicum, and other medicinal and food homologous ingredients on the retina.

Key words: Lutein, Blue light, Retina, Oxidative stress, Inflammation, Functional food, Mice