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Emodin attenuates the impairment of LTP after traumatic brain injury in rat hippocampus
Abstracts P1-m13 Enhanced oligodendrogenesis and neurogenesis in the subventricular zone of neonatal mouse brain following Hypoxia/ischemia Eisuke Kako 1,3 , Naoko Kaneko 1 , Hideki Hida 2 , Kazuya Sobue 3 , Hajime Togari 4 , Kazunobu Sawamoto 1 1 Department of Dev. Regen. Biol., Nagoya City University Grad. Sch. Med. Sci., Nagoya, Japan; 2 Neurophysiol Brain Sci., Japan; 3 Anesthesiol Med. and Crisis Management, Japan; 4 Pediatrics, Japan
Subventricular zone (SVZ) in the postnatal brain contains neural stem cells that have the capacity to regenerate neural tissue after various lesions. Periventricular leukomalacia (PVL), a lesion of white matter around the cerebral ventricles in premature infants, induces long-term neurological deficits including cerebral palsy. Previous studies indicate that hypoxic-ischemic incidents are involved in the development of PVL. However, its precise mechanism remains unclear and currently there is no treatment for PVL. To understand the pathophysiology of PVL and possible molecular/cellular mechanisms for regeneration, we have established a mouse model of PVL using neonatal hypoxia-ischemia. BrdU-labeling and staining for cell-type specific markers revealed that neurogenesis and gliogenesis were activated in the SVZ, suggesting that SVZ-derived progenitors could contribute to the regeneration of damaged neural tissue after PVL. doi:10.1016/j.neures.2009.09.595
P1-m14 Real-time direct measurement of spinal cord blood flow at the point of compression Tadao Morino, Tadanori Ogata, Kei Morizane, Gotaro Yamaoka, Haruyasu Yamamoto Department Orthop. Surg., Ehime University, Ehime, Japan To evaluate the change in thoracic spinal cord blood flow by compression force, we developed real-time measurement system of spinal cord blood flow at the site of compression. The spinal blood flow decreased upon each increase in the compression force. Complete ischemia was reached using a 20 g weight. After decompression, the blood flow level in the 20 min complete ischemia group was significantly higher than that in the 40 min complete ischemia group. The hind-limb motor function, evaluated by the BBB scale and the frequency of voluntary standing, in the 40 min complete ischemia group was significantly less than that in the sham group (without compression), while no significant difference was observed between the 20 min ischemia group and the sham group. Extensive breakdown of blood-spinal cord barrier integrity and the following microglia proliferation and apoptotic cell death were detected in the 40 min complete ischemia group. Duration of ischemia/compression and blood flow recovery of the spinal cord are very important factors in the recovery of motor function after a spinal cord injury. doi:10.1016/j.neures.2009.09.596
P1-m15 Emodin attenuates the impairment of LTP after traumatic brain injury in rat hippocampus Mitsue Takeya, Hiroshi Hasuo, Takashi Akasu Department Physiol., Kurume University Sch. Med., Kurume, Japan Emodin is an active compound of Rhubarb extracts. We have previously shown that emodin suppresses glutamatergic synaptic transmission in CA1 pyramidal cells in vitro. In the present study, we investigated the effects of emodin (10 mg/kg, i.p.) applied 10 min after a moderate (4.2 atm) lateral fluid percussion injury (FPI). After a survival period of seven days, horizontal brain slices were obtained from FPI, FPI treated with emodin (FPI-emod) or sham-operated rats. Field EPSPs were evoked by stimulation of Schaffer collaterals (0.05 Hz) and two trains of high-frequency stimulation (HFS, 100 Hz, 1 s) were delivered to induce long-term potentiation (LTP). The magnitude of LTP determined 50–60 min after the HFS in FPI group (117% of control) was significantly smaller than that of sham group (160% of control). In FPI-emod group, the magnitude of LTP was 160% of control, indicating a significant improvement of LTP in CA1 area (p < 0.001). These results suggest that emodin may be effective therapeutic agents for traumatic brain injury.
P1-m16 Involvement of glial and fibrotic scars in neural tissue repair after brain trauma Nozomu Yoshioka 1,2 , Shin-Ichi Hisanaga 2 , Hitoshi Kawano 1 Tokyo Metropolitan Inst. for Neurosci., Japan; Japan
By 14 days after traumatic brain injury (TBI), the fibrotic scar is formed in the lesion center, while the glial scar is formed surrounding the fibrotic scar. To examine the physiological role of the two scars, immunohistochemical analysis with Evans blue (EB) leakage experiment was performed in mice subjected to the TBI. EB was widely leaked around the lesion site at 3 days after TBI and restricted within the fibrotic scar by 14 days after. Reactive astrocytes increased at 3 days after TBI around the region of EB leaking and surrounded the fibrotic scar at 14 days after. Glucose transporter-1, a blood-brain barrier (BBB) marker, was localized in blood vessels outside the fibrotic scar, but not inside, indicating that the BBB was not repaired within the fibrotic scar. The glia limitans created by reactive astrocytes and the basal membrane elaborated by fibroblasts formed a distinct boundary between the two scars, which separated BBB+ and BBB− areas. It is, therefore, proposed that the glial scar is involved in the repair of BBB whereas the fibrotic scar encloses lesion site. doi:10.1016/j.neures.2009.09.598
P1-m17 Neurotrophic activities of transplanted neural progenitor cells expressing mutant NT3 in injured spinal cord Kazuo Kusano, Mitsuhiro Enomoto, Kenichi Shinomiya Department Orthop., Tokyo Medical and Dental University, Japan NT3 plays a protective role in injured CNS tissue through interaction with trk receptors. However, NT3 also binds to the p75 receptor (p75NTR), and NT3-p75NTR signaling mediates neural apoptosis and inhibition of axonal regeneration. We have generated a mutant NT3 (D15A/-p75) with a reduced ability to bind to p75NTR. We examined whether transplantation of neural progenitor cells (NPCs) expressing D15A/-p75 would be a successful therapy for the chronic phase of spinal cord injury. NPCs derived from E16 rat hippocampi were cultured and transfected with lentivirus containing D15A/-p75 or GFP. The cells were transplanted into the contused rat spinal cords 6 weeks after injury. We scored their behavior every week. Histological assessments were performed 8 weeks after the transplantation. We found that D15A/-p75 transplants displayed better survival than GFP transplants. Moreover, rats with D15A/-p75 transplants exhibited enhanced myelin formation and partially improved recovery of hindlimb function. We suggest that these effects result from the absence of negative signaling by NT3-p75NTR. doi:10.1016/j.neures.2009.09.599
P1-m18 The molecular mechanism of repairing spinal cord injury by 1-deoxy-nor-sominone (Denosomin) Aiko Nagata 1,2 , Kiyoshi Teshigawara 1 , Yuji Matsuya 3 , Hideo Nemoto 3 , Chihiro Tohda 1 1 Div. of Biofunctional Evaluation, Inst. of Natural Med., University of Toyama, Toyama, Japan; 2 Pathogenic Biochem., Inst. of Natural Med., University of Toyama, Toyama, Japan; 3 Organochem. Design and Synthesis, Fac. of Pharmaceu. Sci., University of Toyama, Toyama, Japan
We have found that oral administration of 1-deoxy-nor-sominone (Denosomin), improved hindlimb function and inflammation in spinal cord injured mice. In the present study, we aimed to investigate direct target molecules of Denosomin and subsequent transcriptional changes induced by Denosomin to identify key factors for functional recovery of the spinal neuronal network. Primary cultured spinal cord neurons (SD rat, E18) were stimulated by 1 M Denosomin or vehicle solution for 1 h. Phosphorylation profiles of two cell lysates were compared using tyrosine phosphorylated receptor arrays. In addition, gene profile changes after spinal cord injury and Denosomin treatment (10 mol/kg, p.o., for 3 days) in mice were investigated by DNA Array. We are now confirming that candidate factors shown in those approaches actually contribute to repairing signals in spinal cord injury. doi:10.1016/j.neures.2009.09.600
P1-m19 Identification of the full-length form of Prune2, a neuroblastoma-related protein Daisuke Tsuchimoto Div. Neurofunc Genomics, Med. Inst. Bioreg., Kyushu University, Fukuoka, Japan
doi:10.1016/j.neures.2009.09.597
1
S125
2
Tokyo Metro University,
Human Prune2 is a putative protein predicted by analysis of genome sequence. Its N-terminal region shows homology to Prune. C9orf65 encodes the N-terminal region and was reported to be highly expressed in leiomyosarcomas (LMS) compared to gastrointestinal stromal tumors (GIST). The C-terminal region was reported as BCHmotif-containing molecule at the C-terminal region 1 (BMCC1). The high expression of BMCC1 in neuroblastomas was shown to correlate with favorable prognosis. In this study, we have purified mouse proteins that bind 8-oxo-GTP, and identified an
Subventricular zone (SVZ) in the postnatal brain contains neural stem cells that have the capacity to regenerate neural tissue after various lesions. Periventricular leukomalacia (PVL), a lesion of white matter around the cerebral ventricles in premature infants, induces long-term neurological deficits including cerebral palsy. Previous studies indicate that hypoxic-ischemic incidents are involved in the development of PVL. However, its precise mechanism remains unclear and currently there is no treatment for PVL. To understand the pathophysiology of PVL and possible molecular/cellular mechanisms for regeneration, we have established a mouse model of PVL using neonatal hypoxia-ischemia. BrdU-labeling and staining for cell-type specific markers revealed that neurogenesis and gliogenesis were activated in the SVZ, suggesting that SVZ-derived progenitors could contribute to the regeneration of damaged neural tissue after PVL. doi:10.1016/j.neures.2009.09.595
P1-m14 Real-time direct measurement of spinal cord blood flow at the point of compression Tadao Morino, Tadanori Ogata, Kei Morizane, Gotaro Yamaoka, Haruyasu Yamamoto Department Orthop. Surg., Ehime University, Ehime, Japan To evaluate the change in thoracic spinal cord blood flow by compression force, we developed real-time measurement system of spinal cord blood flow at the site of compression. The spinal blood flow decreased upon each increase in the compression force. Complete ischemia was reached using a 20 g weight. After decompression, the blood flow level in the 20 min complete ischemia group was significantly higher than that in the 40 min complete ischemia group. The hind-limb motor function, evaluated by the BBB scale and the frequency of voluntary standing, in the 40 min complete ischemia group was significantly less than that in the sham group (without compression), while no significant difference was observed between the 20 min ischemia group and the sham group. Extensive breakdown of blood-spinal cord barrier integrity and the following microglia proliferation and apoptotic cell death were detected in the 40 min complete ischemia group. Duration of ischemia/compression and blood flow recovery of the spinal cord are very important factors in the recovery of motor function after a spinal cord injury. doi:10.1016/j.neures.2009.09.596
P1-m15 Emodin attenuates the impairment of LTP after traumatic brain injury in rat hippocampus Mitsue Takeya, Hiroshi Hasuo, Takashi Akasu Department Physiol., Kurume University Sch. Med., Kurume, Japan Emodin is an active compound of Rhubarb extracts. We have previously shown that emodin suppresses glutamatergic synaptic transmission in CA1 pyramidal cells in vitro. In the present study, we investigated the effects of emodin (10 mg/kg, i.p.) applied 10 min after a moderate (4.2 atm) lateral fluid percussion injury (FPI). After a survival period of seven days, horizontal brain slices were obtained from FPI, FPI treated with emodin (FPI-emod) or sham-operated rats. Field EPSPs were evoked by stimulation of Schaffer collaterals (0.05 Hz) and two trains of high-frequency stimulation (HFS, 100 Hz, 1 s) were delivered to induce long-term potentiation (LTP). The magnitude of LTP determined 50–60 min after the HFS in FPI group (117% of control) was significantly smaller than that of sham group (160% of control). In FPI-emod group, the magnitude of LTP was 160% of control, indicating a significant improvement of LTP in CA1 area (p < 0.001). These results suggest that emodin may be effective therapeutic agents for traumatic brain injury.
P1-m16 Involvement of glial and fibrotic scars in neural tissue repair after brain trauma Nozomu Yoshioka 1,2 , Shin-Ichi Hisanaga 2 , Hitoshi Kawano 1 Tokyo Metropolitan Inst. for Neurosci., Japan; Japan
By 14 days after traumatic brain injury (TBI), the fibrotic scar is formed in the lesion center, while the glial scar is formed surrounding the fibrotic scar. To examine the physiological role of the two scars, immunohistochemical analysis with Evans blue (EB) leakage experiment was performed in mice subjected to the TBI. EB was widely leaked around the lesion site at 3 days after TBI and restricted within the fibrotic scar by 14 days after. Reactive astrocytes increased at 3 days after TBI around the region of EB leaking and surrounded the fibrotic scar at 14 days after. Glucose transporter-1, a blood-brain barrier (BBB) marker, was localized in blood vessels outside the fibrotic scar, but not inside, indicating that the BBB was not repaired within the fibrotic scar. The glia limitans created by reactive astrocytes and the basal membrane elaborated by fibroblasts formed a distinct boundary between the two scars, which separated BBB+ and BBB− areas. It is, therefore, proposed that the glial scar is involved in the repair of BBB whereas the fibrotic scar encloses lesion site. doi:10.1016/j.neures.2009.09.598
P1-m17 Neurotrophic activities of transplanted neural progenitor cells expressing mutant NT3 in injured spinal cord Kazuo Kusano, Mitsuhiro Enomoto, Kenichi Shinomiya Department Orthop., Tokyo Medical and Dental University, Japan NT3 plays a protective role in injured CNS tissue through interaction with trk receptors. However, NT3 also binds to the p75 receptor (p75NTR), and NT3-p75NTR signaling mediates neural apoptosis and inhibition of axonal regeneration. We have generated a mutant NT3 (D15A/-p75) with a reduced ability to bind to p75NTR. We examined whether transplantation of neural progenitor cells (NPCs) expressing D15A/-p75 would be a successful therapy for the chronic phase of spinal cord injury. NPCs derived from E16 rat hippocampi were cultured and transfected with lentivirus containing D15A/-p75 or GFP. The cells were transplanted into the contused rat spinal cords 6 weeks after injury. We scored their behavior every week. Histological assessments were performed 8 weeks after the transplantation. We found that D15A/-p75 transplants displayed better survival than GFP transplants. Moreover, rats with D15A/-p75 transplants exhibited enhanced myelin formation and partially improved recovery of hindlimb function. We suggest that these effects result from the absence of negative signaling by NT3-p75NTR. doi:10.1016/j.neures.2009.09.599
P1-m18 The molecular mechanism of repairing spinal cord injury by 1-deoxy-nor-sominone (Denosomin) Aiko Nagata 1,2 , Kiyoshi Teshigawara 1 , Yuji Matsuya 3 , Hideo Nemoto 3 , Chihiro Tohda 1 1 Div. of Biofunctional Evaluation, Inst. of Natural Med., University of Toyama, Toyama, Japan; 2 Pathogenic Biochem., Inst. of Natural Med., University of Toyama, Toyama, Japan; 3 Organochem. Design and Synthesis, Fac. of Pharmaceu. Sci., University of Toyama, Toyama, Japan
We have found that oral administration of 1-deoxy-nor-sominone (Denosomin), improved hindlimb function and inflammation in spinal cord injured mice. In the present study, we aimed to investigate direct target molecules of Denosomin and subsequent transcriptional changes induced by Denosomin to identify key factors for functional recovery of the spinal neuronal network. Primary cultured spinal cord neurons (SD rat, E18) were stimulated by 1 M Denosomin or vehicle solution for 1 h. Phosphorylation profiles of two cell lysates were compared using tyrosine phosphorylated receptor arrays. In addition, gene profile changes after spinal cord injury and Denosomin treatment (10 mol/kg, p.o., for 3 days) in mice were investigated by DNA Array. We are now confirming that candidate factors shown in those approaches actually contribute to repairing signals in spinal cord injury. doi:10.1016/j.neures.2009.09.600
P1-m19 Identification of the full-length form of Prune2, a neuroblastoma-related protein Daisuke Tsuchimoto Div. Neurofunc Genomics, Med. Inst. Bioreg., Kyushu University, Fukuoka, Japan
doi:10.1016/j.neures.2009.09.597
1
S125
2
Tokyo Metro University,
Human Prune2 is a putative protein predicted by analysis of genome sequence. Its N-terminal region shows homology to Prune. C9orf65 encodes the N-terminal region and was reported to be highly expressed in leiomyosarcomas (LMS) compared to gastrointestinal stromal tumors (GIST). The C-terminal region was reported as BCHmotif-containing molecule at the C-terminal region 1 (BMCC1). The high expression of BMCC1 in neuroblastomas was shown to correlate with favorable prognosis. In this study, we have purified mouse proteins that bind 8-oxo-GTP, and identified an