5,6,7-Trimethoxyflavone protects from ischemic brain injury by attenuating BBB leakage

Ischemic stroke results from occlusion of a cerebral artery. According to current treatment guidelines, thrombolytic therapy and thrombectomy can effectively restore blood flow and salvage surviving neurons. However, ischemia-reperfusion injury post-stroke can lead to sustained neural dysfunction and blood-brain barrier (BBB) disruption, initiating an inflammatory cascade. 5,6,7-Trimethoxyflavone (TMF), a newly identified flavonoid with anti-inflammatory properties, has not been fully explored in the context of ischemic diseases or hypoxia-induced injury. In this study, TMF or a vehicle was intravenously administered to adult male C57BL/6 J mice subjected to 60-min middle cerebral artery occlusion (MCAO), followed by intraperitoneal injections 4.5 h after reperfusion and daily for an additional two days. Bulk RNA sequencing was conducted to investigate the molecular mechanisms of TMF in ischemic brain injury. Infarct size, BBB integrity, cerebral endothelial cell structure, and neurobehavioral outcomes were assessed to evaluate the effects of TMF treatment. TMF treatment significantly reduced neuronal death, preserved vascular integrity, decreased immune cell infiltration, inhibited the immune response, and alleviated post-stroke neurological deficits. Mechanistically, TMF mitigated BBB-associated protein loss, disrupted cytokine interactions linked to damage, and exhibited notable anti-inflammatory effects.