Freeze-Dried Extracts of Eruca sativa Selectively Inhibit Nuclear Factor-κB and Vascular Endothelial Growth Factor...

Diabetic retinopathy and age-related macular degeneration are driven by retinal pigment epithelium (RPE) dysfunction accompanied by chronic inflammation and an upregulation of vascular endothelial growth factor (VEGF). This study investigated the protective effects of Eruca sativa freeze-dried extract against metabolic and inflammatory stress in the ARPE-19 retinal epithelial cell line. Gene expression levels and protein contents were assessed via quantitative real-time polymerase chain reaction and Western blots. VEGF secretion and cell calcium levels were quantified using enzyme-linked immunosorbent assay and Fluo-4 NW calcium assay, respectively. Freeze-dried E. sativa extract (ESF) exposure did not induce any cytotoxicity across the concentration range tested. Under thapsigargin (Tg) stimulation, ESF at 1 mg/mL significantly reduced VEGF expression and protein secretion by 32% and 34%, respectively. Tg-induced calcium mobilization within cells and the expression of unfolded protein response markers, including CCAAT/enhancer-binding protein homologous protein, binding immunoglobulin protein, and X-box binding protein-1, remained unchanged following ESF exposure. Under lipopolysaccharide stimulation, in a dose-dependent manner, ESF suppressed nuclear factor-κB (NF-κB) phosphorylation, tumor necrosis factor-α, and interleukin-1β expression; however, c-Jun N-terminal kinase signaling was not affected. Hot-air-dried E. sativa extract demonstrated contrasting regulatory profiles, which exhibited a broader modulation of endoplasmic reticulum stress and mitogen-activated protein kinase signaling. Collectively, the findings demonstrate that ESF selectively attenuates inflammatory and angiogenic responses by specifically inhibiting the NF-κB-VEGF axis. Dehydration, therefore, is a critical method determining ESF bioactivity, preserving native phytochemicals that confer focused anti-inflammatory and anti-angiogenic efficacy in RPE cells.