Fig. 1. Iron is elevated during aging.

A Heat map displays the changes of differential gene expression in two groups. Data were derived from Gene Expression Omnibus (GEO) data sets GSE58137. B KEGG pathway analysis of upregulated genes. ARPE-19 cells were treated with TBH (100 μM) for 48 h to induce cell senescence models. C Images of SA-β-Gal staining of ARPE-19 cells (n = 3). Scale bars, 100 μm. D Immunofluorescence staining of p-H2AX and 8-OhdG. Scale bars, 25 μm. E Intracellular Fe²⁺ levels were detected by the FerroOrange probe (1 μM, 30 min) (n = 3). Scale bars, 25 μm. F SA-β-Gal staining of mouse retina. Scale bars, 100 μm. G Immunofluorescence staining of p-H2AX in mouse retina. Scale bars, 25 μm. H The protein content of IFN-β, TNF-α and IL-6 in mouse retina was assessed by Western blot (n = 3). Mean ± SD. I lillie’s Ferrous Iron stain showing Fe²⁺ deposition in mouse retina. Blue depositions represent the accumulation of Fe²⁺. Scale bars, 100 μm. Data are shown as Mean ± SD. *p < 0.05 vs. control group.