ETHNOPHARMACOLOGICAL RELEVANCE:Ophiopogonis Radix (Mai-Dong) has been widely used in traditional Chinese medicine for the treatment of cardiovascular diseases, particularly those associated with ischemia and impaired cardiac function. Methylophiopogonanone A (MOA), a bioactive homoisoflavonoid isolated from Ophiopogonis Radix, has demonstrated antioxidant and anti-inflammatory activities; however, its role and molecular mechanisms in myocardial ischemia-reperfusion injury (MIRI) remain unclear.
AIM OF THE STUDY:This study aimed to investigate the cardioprotective effects of MOA in MIRI and to determine whether VEGFR2-associated PI3K/Akt signaling, inhibitory phosphorylation of GSK-3β, and preservation of mitochondrial function contribute to these effects.
MATERIALS AND METHODS:MOA-VEGFR2 target engagement and stabilization were assessed using computational prediction and biochemical target-stability assays. The cardioprotective effects of MOA were evaluated in a rat myocardial ischemia-reperfusion model and in primary cardiomyocytes subjected to oxygen-glucose deprivation/reoxygenation (OGD/R), with emphasis on cardiac function, infarct size, mitochondrial injury, mitochondrial permeability transition pore (mPTP) opening, and VEGFR2/PI3K/Akt/GSK-3β signaling. The involvement of VEGFR2 and PI3K signaling was further examined using VEGFR2 siRNA, SU5416, and LY294002.
RESULTS:Integrative target screening prioritized VEGFR2/KDR as a functionally relevant candidate target of MOA in MIRI. Molecular docking and molecular dynamics simulations provided structural predictions; DARTS, CETSA, and ITDRF-CETSA supported VEGFR2 target engagement by MOA, whereas CHX-chase analysis showed a prolonged VEGFR2 protein half-life. In vivo, MOA reduced infarct size, improved cardiac function, lowered serum CK-MB, LDH, and cTnI levels, increased myocardial ATP content and SOD activity, enhanced phosphorylation of VEGFR2, PI3K, Akt, and GSK-3β, suppressed mPTP opening, and preserved mitochondrial ultrastructure. In vitro, MOA improved the viability of OGD/R-treated cardiomyocytes, decreased apoptosis and ROS accumulation, restored ΔΨm and ATP production, and inhibited mPTP opening. These protective effects were partially attenuated by VEGFR2 silencing, SU5416, or LY294002, supporting roles for VEGFR2-associated PI3K/Akt signaling and inhibitory phosphorylation of GSK-3β in MOA-mediated cardioprotection.
CONCLUSION:MOA attenuates acute MIRI and preserves mitochondrial function. The findings support a model in which MOA-associated VEGFR2 target engagement and increased VEGFR2 protein stability are accompanied by enhanced PI3K/Akt signaling and inhibitory phosphorylation of GSK-3β. However, direct physical binding to VEGFR2 and classical VEGFR2 agonism were not established.