Functional recovery of neuronal activity in rat whisker-barrel cortex sensory pathway from freezing injury after transplantation of adult bone marrow stromal cells

The effect of transplantation of adult bone marrow stromal cells (MSCs) into the freeze-lesioned left barrel field cortex in the rat was investigated by measurement of local cerebral glucose utilization (ICMRglc) in the anatomic structures of the whisker-to-barrel cortex sensory pathway. Bone marrow stromal cells or phosphate-buffered saline (PBS) were injected intracerebrally into the boundary zone 1 h after induction of the freezing cortical lesion. Three weeks after surgery, the 21 [C-14]deoxyglucose method was used to measure ICMRgfc during right whisker stimulation. The volume of the primary necrotic freezing lesion was significantly reduced (P < 0.05), and secondary retrograde degeneration in the left ventral posteromedial (VPM) thalamic nucleus was diminished in the MSC-treated group. Local cerebral glucose utilization measurements showed that the freezing cortical lesion did not alter the metabolic responses to stimulation in the brain stem trigeminal nuclei, but eliminated the responses in the left VPM nucleus and periphery of the barrel cortex in the PBS-treated group. The left/right (stimulated/unstimulated) ICMRglc ratios were significantly improved in both the VPM nucleus and periphery of the barrel cortex in the MSC-treated group compared with the PBS-treated group (P < 0.05). These results indicate that MSC transplantation in adults may stimulate metabolic and functional recovery in injured neuronal pathways.