Poloxamer 188 Modulates Cytoskeletal Dynamics and Mitochondrial Reassembly during Endothelial Repair in Vitro

Poloxamer 188 (P188), a membrane sealing triblock copolymer approved by the FDA, has shown potential in tissue repair. Although mechanisms mediating P188 induced repair are increasingly better understood, its intracellular effects remain elusive. This study investigated whether P188 influences cytoskeletal remodeling and mitochondrial recovery in a brain endothelium model. Primary mouse brain microvascular endothelial cells (mBECs) were subjected to a scratch wound assay. P188 uptake was tracked with a fluorophore conjugated analog, and actin dependence was tested with pharmacological disruption. Actin remodeling was assessed by phalloidin staining, mitochondrial integrity by BioTracker 488 following injury, and cellular ATP content by luminescence assay. P188 was internalized by mBECs in an actin dependent manner, with uptake abolished by cytoskeletal disruption. Treatment enhanced lamellipodia and stress fiber formation during wound closure. P188 preserved mitochondrial mass and promoted redistribution toward the wound edge in response to injury. ATP assays confirmed improved recovery of cellular energy levels 24 h post injury compared to controls. P188 enhances endothelial wound closure not only by stabilizing membranes but also by modulating intracellular processes. By supporting cytoskeletal organization, mitochondrial redistribution, and ATP recovery, P188 facilitates coordinated structural and metabolic repair mechanisms of the brain endothelium.