Hydroxytyrosol from Olive Oil Mitigates Endothelial Dysfunction in Diabetic Foot Ulcers via Redox, Inflammatory, and Survival Pathways

Diabetic foot ulcers (DFUs) remain a devastating complication of diabetes mellitus, with endothelial dysfunction playing a central role in their pathophysiology. Despite advances in wound care, current therapies often fail to address the complex molecular underpinnings of impaired healing. Here, we explored hydroxytyrosol (Hy), a phenolic compound mainly found in olive oil, as a potential therapeutic for hyperglycemia-induced endothelial dysfunction. Using network pharmacology, we identified 170 potential targets of Hy in DFU treatment, with Nrf2 (Nuclear factor erythroid 2-related factor 2), NF-κB (Nuclear Factor kappa-light-chain-enhancer of activated B cells), AKT (serine/threonine protein kinase), and caspase-3 emerging as crucial hub proteins. Molecular docking revealed strong binding affinities (<-6.27 kcal/mol), particularly with Nrf2. In human endothelial cells exposed to a hyperglycemic microenvironment (HGM), Hy (5-10 μM) significantly restored cell viability while promoting Nrf2 nuclear translocation. This activation enhanced downstream antioxidant enzymes Heme Oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1), Catalase (CAT) and suppressed oxidative stress markers p22phox, Thioredoxin Interacting Protein (TXNIP). Hy inhibited NF-κB signaling and pro-inflammatory cytokines interleukin-6 (IL-6), interleukin-18 (IL-18) under hyperglycemic conditions. The compound also reversed HGM-induced suppression of angiogenic factors, Vascular Endothelial Growth Factor (VEGF-A), Hypoxia-inducible factor 1-alpha (HIF-1α), improving tube formation and migration in functional assays. Mechanistically, Hy restored AKT phosphorylation and modulated the BAX/BCL2 ratio, protecting endothelial cells from apoptosis. Our findings highlight Hy's multifaceted action across redox, inflammatory, and survival pathways as a significant advantage over current single-target therapies. While in vitro results are promising, animal models are needed to validate Hy's efficacy in the complex DFU microenvironment. Nevertheless, Hy's favorable absorption-distribution-metabolism-excretion (ADME) profile and pleiotropic effects position it as an intriguing candidate for DFU management, potentially bridging preventive and regenerative approaches in diabetic wound healing.