Photobiomodulation in photothrombotic stroke

Stroke is a leading cause of death both in the United States and overseas, and causes physical, emotional, and financial burdens for patients and their families. Treatment options are limited and require rapid administration to be effective. Photobiomodulation (PBM), which modulates mitochondrial function and cell signaling with near-infrared light, may hold promise as a treatment strategy. In our work, PBM was administered to rats undergoing a photothrombotic (PT) stroke model which generates reproducible cortical infarcts via a photochemical reaction. We found that PBM protected against neurological deficits after PT stroke, and prevented cellular injury and death in the peri-infarct area. PBM reduced reactive gliosis and inflammation, and shifted microglial polarization toward an antiinflammatory phenotype, all the while preventing mitochondrial dysfunction. These effects were accompanied by increasing neurogenesis in the penumbra. In this chapter, we detail these efforts and compare them to others to examine the potential of PBM in stroke.