Effect of exosomes derived from multipluripotent mesenchymal stromal cells on functional recovery and neurovascular plasticity in rats after traumatic brain injury

Two groups of 8 Wistar rats were subjected to TBI, followed 24 hours later by tail vein injection of 100 μg protein of exosomes derived from MSCs or an equal volume of vehicle (phosphate-buffered saline). A third group of 8 rats was used as sham-injured, sham-treated controls. To evaluate cognitive and sensorimotor functional recovery, the modified Morris water maze, modified Neurological Severity Score, and foot-fault tests were performed. Animals were killed at 35 days after TBI. Histopathological and immunohistochemical analyses were performed for measurements of lesion volume, neurovascular remodeling (angiogenesis and neurogenesis), and neuroinflammation.

Compared with the saline-treated group, exosome-treated rats with TBI showed significant improvement in spatial learning at 34-35 days as measured by the modified Morris water maze test (p