Kisspeptin-54 Restores Blood–Brain Barrier Integrity via GATA-4 in Ischemic Stroke

Abstract

Ischemic stroke damages the blood–brain barrier (BBB), worsening neuronal injury. Treatments to protect the BBB are limited. We evaluated the neurovascular protective capacity of Kisspeptin-54 in ischemic stroke using in vivo and in vitro models. In vivo, mice underwent middle cerebral artery occlusion (MCAO), and cerebral infarct volume, neurological function, and blood–brain barrier (BBB) permeability were evaluated. In vitro, human brain microvascular endothelial cells (HBMVECs) were exposed to oxygen–glucose deprivation/reperfusion (OGD/R) to assess the effects of Kisspeptin-54 on paracellular flux and transendothelial electrical resistance (TEER). Additionally, GATA-4 was silenced to investigate its role in mediating protection. Our results showed that cortical ischemia downregulated KISS-1 metastasis-suppressor (KISS1, 59% mRNA; 55% protein) and G protein-coupled receptor 54 (GPR54, 54% mRNA; 48% protein), with a 32% decline in circulating Kisspeptin-54. Prophylactic Kisspeptin-54 reduced cerebral infarct volume by 42%, enhanced neurological performance by 49%, and decreased BBB leakage by 26%, with near-complete occludin recovery. In vitro: Kisspeptin-54 treatment reduced paracellular flux by 48% and increased transendothelial resistance by 60%. GATA-4 silencing abolished Kisspeptin-54-induced occludin restoration, increasing permeability by 65% and diminishing barrier resistance by 28%. This study reveals Kisspeptin-54 modulates BBB stability via GATA-4-driven occludin expression, highlighting the KISS1/GPR54 pathway as a potential therapeutic target for ischemic stroke.