Salidroside suppresses hypoxia-induced ocular angiogenesis by modulating the acetylation of PFKFB3 protein in endothelial cells and regulating glycolytic activity

Background: Pathological ocular angiogenesis represents a leading cause of severe vision impairment, predominantly mediated by hypoxia-induced activation of endothelial glycolysis. Salidroside, the principal bioactive constituent of Rhodiola rosea, has exhibited protective effects in multiple retinal disorders; however, its direct regulatory role in glycolytic metabolism remains poorly understood. This study investigates whether salidroside exerts anti-angiogenic effects through targeting PFKFB3, a key regulator of glycolysis.

Methods: Potential molecular targets were identified via network pharmacology analysis, followed by experimental validation of the interaction between salidroside and PFKFB3 using molecular docking and cellular thermal shift assay (CETSA). In vivo therapeutic efficacy was assessed in an oxygen-induced retinopathy (OIR) mouse model, with evaluation of retinal neovascularization, glycolytic activity, and post-translational modifications of PFKFB3. In vitro studies employed hypoxic human umbilical vein endothelial cells (HUVECs) to elucidate underlying mechanisms through functional assays and metabolic profiling. PFKFB3 overexpression and pharmacological inhibition of deacetylases were performed to confirm target specificity.

Results: Network pharmacology analysis highlighted PFKFB3 as a central intersecting target with high binding affinity for salidroside, which was subsequently confirmed experimentally. In OIR mice, salidroside treatment significantly reduced pathological retinal neovascularization, suppressed glycolytic activation, and attenuated PFKFB3 acetylation, phosphorylation at serine 461 (S461), and cytosolic translocation. In vitro, salidroside ameliorated hypoxia-induced endothelial dysfunction and inhibited glycolytic flux-effects that were reversed upon PFKFB3 overexpression. Significantly, concurrent administration of the deacetylase inhibitor nicotinamide (NAM) effectively nullified the effects of salidroside, which is associated with the inhibition of PFKFB3 modifications and glycolytic activity.

Conclusions: Salidroside directly binds to PFKFB3 and promotes its deacetylation, thereby inhibiting downstream phosphorylation, cytosolic translocation, and glycolytic activation in hypoxic endothelial cells. This mechanistic pathway underlies the anti-angiogenic effect of salidroside in the OIR model, supporting its potential as a promising therapeutic agent for neovascular ocular diseases.