1537: LAMIFLO™ ENHANCES COLLATERAL FLOW AND REDUCES INFARCT AND BBB DAMAGE AFTER EXPERIMENTAL STROKE

Introduction: Current therapies for acute ischemic stroke (AIS) fail to address microvascular dysfunction. Lamiflo™, a high-molecular-weight drag-reducing polymer (DRP), enhances microvascular flow via hemodynamic modulation. We tested its efficacy when given 1 or 3 hours after transient middle cerebral artery occlusion (tMCAO). Methods: Wistar rats underwent 3.5-hour monofilament tMCAO. Lamiflo™ (5 ppm) or saline was administered i.v. at 1 or 3 h (n=5/group). At 3.5 h, Laser Speckle Contrast Imaging (LSCI) was used to evaluate cortical microcirculation. On day 1, neurobehavior was evaluated, followed by post-mortem infarct volume (TTC), and blood-brain barrier (BBB) permeability (Evans Blue) determination. Results: tMCAO progressively impaired cortical microcirculation, leading to tissue ischemia and BBB disruption. Lamiflo™ improved cortical microcirculation via collateral flow enhancement, thereby reducing infarct volume, BBB degradation, leading to improved functional outcome (all p< 0.05). DRP efficacy reduced with the time of application from 1 h to 3 hours after tMCAO, but remained significant Conclusions: Lamiflo™ preserves cerebral microcirculation via collateral flow enhancement, limits infarct and BBB damage, and improves outcomes up to 3 h post-tMCAO, supporting its use as a microcirculatory adjunct in AIS.