A pleiotropic NO-releasing butylphthalide derivative attenuates ischemic stroke by preserving blood-brain barrier integrity via the eNOS/Cav-1/MMP-9 pathway.

Ischemic stroke is a leading cause of mortality and disability worldwide, and disruption of the blood-brain barrier (BBB) plays a critical role in its pathogenesis. Nitric oxide has been reported to exert neuroprotective effects, but its therapeutic application remains limited. This study aimed to evaluate the neuroprotective effects of a nitric oxide-releasing butylphthalide derivative and to elucidate its underlying mechanisms, particularly in relation to BBB preservation. We investigated compound 10 exhibited potent neuroprotective activity with favorable safety and BBB permeability. In a rat middle cerebral artery occlusion (MCAO) model, compound 10 significantly reduced infarct volume and alleviated histopathological damage. Mechanistically, compound 10 suppressed neuroinflammation and oxidative stress, as evidenced by reduced pro-inflammatory cytokine levels, inhibition of microglial activation, and restoration of antioxidant capacity. Notably, compound 10 effectively preserved BBB integrity, as demonstrated by decreased Evans blue extravasation and upregulation of tight junction proteins. Further investigation revealed that these protective effects were mediated through activation of endothelial nitric oxide synthase (eNOS) signaling, leading to increased Cav-1 expression and suppression of MMP-9-dependent BBB disruption. Pharmacological inhibition of eNOS abolished these effects, confirming the critical role of the eNOS/Cav-1/MMP-9 axis. This study identifies compound 10 as a promising multifunctional neuroprotective agent and highlights NO-mediated BBB protection as a viable therapeutic strategy for ischemic stroke.