|Synergistic effects of granulocyte-colony stimulating factor on bone marrow stromal cell transplantation for mice cerebral infarct.|
Masaaki Hokari,Satoshi Kuroda,Yasuhiro Chiba,Katsuhiko Maruichi,Yoshinobu Iwasaki
This study was aimed to assess whether ex vivo treatment with granulocyte-colony stimulating factor (G-CSF) modifies biological properties of bone marrow stromal cells (BMSC) and enhances functional recovery by BMSC transplantation into infarct brain. Immunohistochemistry was conducted to characterize the cultured BMSC. The pharmacological effects of G-CSF on their proliferation, cell cycle, and growth factor production were precisely analyzed, using FACS and ELISA techniques. Non-treated or G-CSF treated BMSC were stereotactically transplanted into the mice brain subjected to cerebral infarct, and its effects on functional and histological aspects were evaluated. The BMSC expressed the receptor for G-CSF. Treatment with 0.1muM of G-CSF significantly enhanced the proliferation of BMSC by increasing their population in S phase, and increased their production of SDF-1alpha, HGF, and NGF. When transplanted into infarct brain, G-CSF treated BMSC significantly improved motor function as early as 2 weeks after transplantation, whereas non-treated BMSC did 4 weeks after transplantation. These findings strongly suggest that G-CSF may enhance the proliferation and growth factor production of the cultured BMSC and accelerate functional restoration by BMSC transplantation. Such pharmacological activation of the BMSC may contribute to successful clinical application of BMSC transplantation therapy for ischemic stroke.
|Bone marrow stromal cells protect and repair damaged neurons through multiple mechanisms.|
Masaaki Hokari,Satoshi Kuroda,Hideo Shichinohe,Shunsuke Yano,Kazutoshi Hida,Yoshinobu Iwasaki
Journal of neuroscience research
A surprising shortage of information surrounds the mechanism by which bone marrow stromal cells (BMSC) restore lost neurologic functions when transplanted into the damaged central nervous system. To clarify the issue, the BMSC were cocultured with the neurons using two paradigms: the cell-mixing coculture technique and three-dimensional coculture technique. The green fluorescent protein (GFP)-expressing BMSC were cocultured with the PKH-26-labelled neurons, using cell mixing coculture technique. GFP-positive, PKH-26-negative cells morphologically simulated the neurons and significantly increased the expression of MAP-2, Tuj-1, nestin, and GFAP. GFP/nestin-positive, PKH-26-negative cells increased from 13.6% +/- 6.7% to 32.1% +/- 15.5% over 7 days of coculture. They further enhanced Tuj-1 expression when cocultured with neurons exposed to 100 microM of glutamate for 10 min. About 20-30% of GFP-positive cells became positive for PKH-26 through coculture with the neurons, but the doubly positive cells did not increase when cocultured with glutamate-exposed neurons. Alternatively, the BMSC significantly ameliorated glutamate-induced neuronal damage when cocultured with the three-dimensional coculture technique. The protective effect was more prominent when coculture was started prior to glutamate exposure than when coculture was started just after glutamate exposure. ELISA analysis revealed that the BMSC physiologically produce NGF, BDNF, SDF-1alpha, HGF, TGFbeta-1, and IGF-1 and significantly enhanced the production of NGF and BDNF when cocultured with glutamate-exposed neurons. These findings strongly suggest that the BMSC may protect and repair the damaged neurons through multiple mechanisms, including transdifferentiation, cell fusion, and production of growth factors.
|Peripheral levels of BDNF and NGF in primary headaches.|
F Blandini, L Rinaldi, C Tassorelli, G Sances, M Motta, A Samuele, R Fancellu, G Nappi, A Leon
Cephalalgia : an international journal of headache
Neurotrophins, such as brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), have been implicated in the generation and modulation of pain. To investigate whether alterations in neurotrophin levels can be detected in subjects suffering from nociceptive disorders, such as primary headaches, we determined the peripheral (platelet and plasma) levels of BDNF and NGF in patients suffering from migraine, with or without aura, or cluster headache (CH), in the interictal phase, and in healthy volunteers. All primary headaches patients studied showed significantly decreased platelet levels of BDNF (migraine vs. controls P0.001; CH vs. controls P0.01), while a selective reduction of platelet NGF was observed in migraine sufferers and not in CH patients compared with control subjects (migraine vs. controls P0.001). These changes were not accompanied by significant modifications of neurotrophin plasma levels. Our findings show for the first time that changes in peripheral levels of neurotrophines (BDNF and NGF) occur in patients suffering from different types of primary headaches, suggesting a potential involvement of BDNF and NGF in the pathophysiology of these disorders, and raising the possibility that differences in peripheral neurotrophins may help to distinguish migraine biologically from CH.
|Microglia-Müller glia cell interactions control neurotrophic factor production during light-induced retinal degeneration.|
Harada, Takayuki, et al.
J. Neurosci., 22: 9228-36 (2002)
Activation of microglia commonly occurs in response to a wide variety of pathological stimuli including trauma, axotomy, ischemia, and degeneration in the CNS. In the retina, prolonged or high-intensity exposure to visible light leads to photoreceptor cell apoptosis. In such a light-reared retina, we found that activated microglia invade the degenerating photoreceptor layer and alter expression of neurotrophic factors such as nerve growth factor (NGF), ciliary neurotrophic factor (CNTF), and glial cell line-derived neurotrophic factor (GDNF). Because these neurotrophic factors modulate secondary trophic factor expression in Müller glial cells, microglia-Müller glia cell interaction may contribute to protection of photoreceptors or increase photoreceptor apoptosis. In the present study, we demonstrate the possibility that such functional glia-glia interactions constitute the key mechanism by which microglia-derived NGF, brain-derived neurotrophic factor (BDNF), and CNTF indirectly influence photoreceptor survival, although the receptors for these neurotrophic factors are absent from photoreceptors, by modulating basic fibroblast growth factor (bFGF) and GDNF production and release from Müller glia. These observations suggest that microglia regulate the microglia-Müller glia-photoreceptor network that serves as a trophic factor-controlling system during retinal degeneration.