Long-lasting paracrine effects of human cord blood cells on damaged neocortex in an animal model of cerebral palsy.

Neonatal asphyxia is an important contributor to cerebral palsy (CP), for which there is no effective treatment to date. The administration of human cord blood cells (hUCBCs) is emerging as a therapeutic strategy for the treatment of neurological disorders. However, there are few studies on the application of hUCBCs to the treatment of neonatal ischemia as a model of CP. Experiments and behavioral tests (mainly motor tests) performed on neonatal hypoxia/ischemia have been limited to short-term effects of hUCBCs, but mechanisms of action have not been investigated. We performed a study on the use of hUCBCs in a rat model of neonatal hypoxia/ischemia and investigated the underlying mechanism for therapeutic benefits of hUCBC treatment. hUCBCs were intravenously transplanted into a rat model of neonatal hypoxia ischemia. hUCBCs increased microglia temporarily in the periventricular striatum in the early phase of disease, protected mature neurons in the neocortex from injury, paved the way for the near-normalization of brain damage in the subventricular zone (SVZ), and, in consequence, significantly improved performance in a battery of behavioral tests compared to the vehicle-treated group. Although the transplanted cells were rarely observed in the brain 3 weeks after transplantation, the effects of the improved behavioral functions persisted. Our preclinical findings suggest that the long-lasting positive influence of hUCBCs is derived from paracrine effects of hUCBCs that stimulate recovery in the injured brain and protect against further brain damage.

Granulocyte-macrophage colony-stimulating factor promotes survival of dopaminergic neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced murine Parkinson's disease model.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic cytokine that has the potential for clinical application. The biological effects of GM-CSF have been well characterized, and include stimulation of bone marrow hematopoietic stem cell proliferation and inhibition of apoptosis of hematopoietic cells. In contrast, the therapeutic effects of GM-CSF on the central nervous system in acute injury such as stroke and spinal cord injury have been reported only recently. To better understand the protective effect of GM-CSF on dopaminergic neurons in Parkinson's disease (PD), we investigated the effect of GM-CSF on the survival of dopamine neurons and changes in locomotor behavior in a murine PD model. We investigated the neuroprotective effects of GM-CSF in 1-methyl-4-phenylpyridinium (MPP+)-treated PC12 cells as well as in embryonic mouse primary mesencephalic neurons (PMNs) in vitro. To investigate the role of GM-CSF in vivo, we prepared a mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) PD model, and examined the effects of GM-CSF on dopaminergic neuron survival in the substantia nigra and on locomotor behavior. Treatment with GM-CSF significantly reduced MPP+-induced dopaminergic cell death in PC12 cells and PMNs in vitro. GM-CSF modulated the expression of apoptosis-related proteins, Bcl-2 and Bax, in vitro. Furthermore, administration of GM-CSF (50 microg/kg body weight/day) in vivo for 7 days protected dopaminergic neurons in the substantia nigra and improved locomotor behavior in a mouse MPTP model of PD.

GM-CSF inhibits glial scar formation and shows long-term protective effect after spinal cord injury.

OBJECT: This study investigated the effects of granulocyte macrophage-colony stimulating factor (GM-CSF) on the scar formation and repair of spinal cord tissues in rat spinal cord injury (SCI) model. METHODS: Sprague-Dawley male rats (8 weeks old) were randomly divided into the sham-operated group, spinal cord injury group, and injury with GM-CSF treated group. A spinal cord injury was induced at T9/10 levels of rat spinal cord using a vascular clip. GM-CSF was administrated via intraperitoneal (IP) injection or on the dural surface using Gelfoam at the time of SCI. The morphological changes, tissue integrity, and scar formation were evaluated until 4 weeks after SCI using histological and immunohistochemical analyses. RESULTS: The administration of GM-CSF either via IP injection or local treatment significantly reduced the cavity size and glial scar formation at 3-4 weeks after SCI. GM-CSF also reduced the expression of core proteins of chondroitin sulfate proteoglycans (CSPGs) such as neurocan and NG2 but not phosphacan. In particular, an intensive expression of glial fibriallary acidic protein (GFAP) and neurocan found around the cavity at 4 weeks was obviously suppressed by GM-CSF. Immunostaining for neurofilament (NF) and Luxol fast blue (LFB) showed that GM-CSF preserved well the axonal arrangement and myelin structure after SCI. The expression of GAP-43, a marker of regenerating axons, also apparently increased in the rostral grey matter by GM-CSF. CONCLUSION: These results suggest that GM-CSF could enhance long-term recovery from SCI by suppressing the glial scar formation and enhancing the integrity of axonal structure.