pkh-26 and Brain-Injuries

Previous work from our group has shown that intranasal MSC-treatment decreases lesion volume and improves motor and cognitive behavior after hypoxic-ischemic (HI) brain damage in neonatal mice. Our aim was to determine the kinetics of MSC migration after intranasal administration, and the early effects of MSCs on neurogenic processes and gliosis at the lesion site. HI brain injury was induced in 9-day-old mice and MSCs were administered intranasally at 10days post-HI. The kinetics of MSC migration were investigated by immunofluorescence and MRI analysis. BDNF and NGF gene expression was determined by qPCR analysis following MSC co-culture with HI brain extract. Nestin, Doublecortin, NeuN, GFAP, Iba-1 and M1/M2 phenotypic expression was assessed over time. MRI and immunohistochemistry analyses showed that MSCs reach the lesion site already within 2h after intranasal administration. At 12h after administration the number of MSCs at the lesion site peaks and decreases significantly at 72h. The number of DCX(+) cells increased 1 to 3days after MSC administration in the SVZ. At the lesion, GFAP(+)/nestin(+) and DCX(+) expression increased 3 to 5days after MSC-treatment. The number of NeuN(+) cells increased within 5days, leading to a dramatic regeneration of the somatosensory cortex and hippocampus at 18days after intranasal MSC administration. Interestingly, MSCs expressed significantly more BDNF gene when exposed to HI brain extract in vitro. Furthermore, MSC-treatment resulted in the resolution of the glial scar surrounding the lesion, represented by a decrease in reactive astrocytes and microglia and polarization of microglia towards the M2 phenotype. In view of the current lack of therapeutic strategies, we propose that intranasal MSC administration is a powerful therapeutic option through its functional repair of the lesion represented by regeneration of the cortical and hippocampal structure and decrease of gliosis.

Topics: Administration, Intranasal; Animals; Animals, Newborn; Brain Injuries; Brain-Derived Neurotrophic Factor; Cell Differentiation; Cell Proliferation; Coculture Techniques; Doublecortin Protein; Fluorescent Dyes; Functional Laterality; Ischemia; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Nerve Growth Factor; Nerve Regeneration; Nerve Tissue Proteins; Neuroglia; Organic Chemicals; Time Factors

Stem cell tracking is essential for evaluation of its migration, transplantation and therapeutic response. The aim of this study was to evaluate early distribution of intravenously transplanted rat bone marrow mesenchymal stem cells (BMSCs) in rats with acute cerebral trauma by labeling with (99m)Tc-hexamethylpropyleneamine oxime ((99m)Tc-HMPAO).. (99m)Tc-HMPAO-labeled BMSCs were injected intravenously to trauma rats (n=14) and sham-operated controls (n=13). Gamma camera images were acquired at 4 h after injection, and then organs were removed for gamma counting. Confocal microscope was used to confirm the migration of (99m)Tc-BMSCs by co-labeling with PKH26. Cytometric analysis was performed to evaluate apoptotic or necrotic change until the seventh day after labeling.. (99m)Tc-BMSCs were distributed mostly to lungs, liver and spleen at 4 h, and uptake of these organs was not significantly different between traumatic rats and controls. Meanwhile, the cerebral uptake of (99m)Tc-BMSCs was significantly higher in the traumatic rats than in controls (0.40% vs. 0.20%; P=.0002). Additionally, (99m)Tc-BMSCs' uptake of traumatic hemisphere was significantly higher than that of contralateral ones (0.27% vs. 0.13%; P=.0001) in traumatic rats. Regardless of radiolabeling, BMSCs migrated to traumatic regions, but not to nontraumatic hemispheres. However, gamma camera failed to demonstrate (99m)Tc-BMSCs in traumatic hemispheres. No significant apoptotic or necrotic change was observed until 7 days after radiolabeling.. Early distribution of BMSCs in traumatic brain disease could be monitored by (99m)Tc-labeling, which does not induce cellular death. However, our data showed that the amount of migrated (99m)Tc-BMSCs was not enough to be demonstrated by clinical gamma camera.

Topics: Animals; Apoptosis; Brain; Brain Injuries; Case-Control Studies; Female; Fluorescent Dyes; Gamma Cameras; Liver; Lung; Mesenchymal Stem Cells; Microscopy, Polarization; Necrosis; Organic Chemicals; Radionuclide Imaging; Radiopharmaceuticals; Rats; Rats, Sprague-Dawley; Spleen; Technetium Tc 99m Exametazime; Tissue Distribution

Microglia isolated from a mixed glial culture drawn from neonatal Mongolian gerbils were demonstrated to produce high amounts of brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). The gerbil microglia retained the capability to migrate into the brain parenchyma after intra-arterial injection. We found that exogenously migrated microglia retained their BDNF and GDNF productive ability and expressed large amounts of BDNF and GDNF in damaged brain areas which suggests microglia's role as a protectant of damaged neurons. Since peripherally injected microglia exhibit specific affinity for areas of neural damage within the brain, we suggest that microglia are possible tools for cell therapy of brain damage.

Topics: Animals; Animals, Newborn; Blood-Brain Barrier; Brain; Brain Injuries; Brain Tissue Transplantation; Brain-Derived Neurotrophic Factor; Cell Movement; Cells, Cultured; Fluorescent Dyes; Gerbillinae; Glial Cell Line-Derived Neurotrophic Factor; Hippocampus; Immunohistochemistry; Interferon-gamma; Male; Microglia; Nerve Growth Factors; Nerve Tissue Proteins; Organic Chemicals