Tsuyoshi Sakamoto
Jikei University School of Medicine
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Featured researches published by Tsuyoshi Sakamoto.
Journal of Neuroscience Research | 2000
Kazuhiko Watabe; Toya Ohashi; Tsuyoshi Sakamoto; Yoko Kawazoe; Takao Takeshima; Kiyomitsu Oyanagi; Kiyoharu Inoue; Yoshikatsu Eto; Seung-Ki Kim
Glial cell line‐derived neurotrophic factor (GDNF) has been shown to protect cranial and spinal motoneurons, that suggests potential uses of GDNF in the treatment of spinal cord injury and motor neuron diseases. We examined neuroprotective effect of human GDNF encoded by an adenovirus vector (AxCAhGDNF) on the death of lesioned adult rat spinal motoneurons. The seventh cervical segment (C7) ventral and dorsal roots and dorsal root ganglia of adult Fisher 344 rats were avulsed, and AxCAhGDNF, AxCALacZ (adenovirus encoding β‐galactosidase gene) or PBS was inoculated in C7 vertebral foramen. One week after the avulsion and treatment with AxCALacZ, the animals showed expression of β‐galactosidase activity in lesioned spinal motoneurons. Animals avulsed and treated with AxCAhGDNF showed intense immunolabeling for GDNF in lesioned spinal motoneurons and expression of virus‐induced human GDNF mRNA transcripts in the lesioned spinal cord tissue. Nissl‐stained cell counts revealed that the treatment with AxCAhGDNF significantly prevented the loss of lesioned ventral horn motoneurons 2 to 8 weeks after avulsion, as compared to AxCALacZ or PBS treatment. Furthermore, the AxCAhGDNF treatment ameliorated choline acetyltransferase immunoreactivity in the lesioned motoneurons after avulsion. These results indicate that the adenovirus‐mediated gene transfer of GDNF may prevent the degeneration of motoneurons in adult humans with spinal cord injury and motor neuron diseases. J. Neurosci. Res. 60:511–519, 2000
Journal of Neuroscience Research | 2003
Tsuyoshi Sakamoto; Yoko Kawazoe; Jin-Song Shen; Yasuo Takeda; Yoshihiro Arakawa; Junko Ogawa; Kiyomitsu Oyanagi; Toya Ohashi; Kazutada Watanabe; Kiyoharu Inoue; Yoshikatsu Eto; Kazuhiko Watabe
We examined neuroprotective effects of recombinant adenoviral vectors encoding glial cell line‐derived neurotrophic factor (GDNF), brain‐derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), cardiotrophin‐1 (CT1), insulin‐like growth factor‐1 (IGF1), and transforming growth factor‐β2 (TGFβ2) on lesioned adult rat facial motoneurons. The right facial nerves of adult Fischer 344 male rats were avulsed and removed from the stylomastoid foramen, and adenoviral vectors were injected into the facial canal. Animals avulsed and treated with adenovirus encoding GDNF, BDNF, CNTF, CT1, IGF1 and TGFβ2 showed intense immunolabeling for these factors in lesioned facial motoneurons, respectively, indicating adenoviral induction of the neurotrophic factors in these neurons. The treatment with adenovirus encoding GDNF, BDNF, or TGFβ2 after avulsion significantly prevented the loss of lesioned facial motoneurons, improved choline acetyltransferase immunoreactivity and prevented the induction of nitric oxide synthase activity in these neurons. The treatment with adenovirus encoding CNTF, CT1 or IGF1, however, failed to protect these neurons after avulsion. These results indicate that the gene transfer of GDNF and BDNF and TGFβ2 but not CNTF, CT1 or IGF1 may prevent the degeneration of motoneurons in adult humans with motoneuron injury and motor neuron diseases.
Neuroreport | 2000
Tsuyoshi Sakamoto; Kazuhiko Watabe; Toya Ohashi; Yoko Kawazoe; Kiyomitsu Oyanagi; Kiyoharu Inoue; Yoshikatsu Eto
We examined neuroprotective effects of an adenoviral vector encoding glial cell line-derived neurotrophic factor (Ax-CAhGDNF) on the lesioned adult rat facial motoneurons. After facial nerve avulsion, animals locally injected into the facial canal with AxCALacZ (adenovirus encoding β-galactosidase gene) or AxCAhGDNF showed expression of β-galactosidase activity or intense immunolabeling for GDNF in lesioned facial motoneurons, respectively. The treatment with AxCAhGDNF after avulsion significantly prevented the loss of lesioned facial motoneurons, ameliorated choline acetyltransferase immunoreactivity, and suppressed the activity of nitric oxide synthase in these neurons. These results indicate that the adenovirus-mediated gene transfer of GDNF may prevent the degeneration of motoneurons in adult humans with peripheral nerve injury and motor neuron diseases.
Journal of the Neurological Sciences | 2008
Masahiko Suzuki; Toshiaki Hirai; Yasuhiko Ito; Tsuyoshi Sakamoto; Hisayoshi Oka; Akira Kurita; Kiyoharu Inoue
We report a case of antecollis, or dropped head with Parkinsons disease (PD) induced by pramipexole, a nonergot dopamine agonist. An 80-year-old woman presented with progressively severe neck flexion, which developed within a few weeks of taking pramipexole at 3 mg/day. She had a disturbed gait and complained of difficulty in daily activity because of restricted visual field and severe stooped posture. Surface EMG showed disproportionate tonus of the neck muscles but needle EMG of the neck muscles was normal. Withdrawal of pramipexole resulted in immediate improvement; the patient could keep the head in natural position and walk normally. Pramipexole-induced antecollis may be serious, but is a reversible dystonia in patients with PD. Clinicians should be aware of such complication.
Neuroscience Letters | 2006
Isao Hozumi; Yoko Uchida; Kazuhiko Watabe; Tsuyoshi Sakamoto; Takashi Inuzuka
We examined the effect of growth inhibitory factor (GIF), also called metallothionein-III (MT-III), in brain damage using a stab wound model. The administration of 3 microM purified rat GIF (prGIF) provided significantly improved brain repair compared with controls, whereas the administration of 15 microM prGIF reduced brain repair compared with controls. To maintain the continuous effect of GIF, we generated an adenoviral vector encoding rat GIF and the myc epitope (AxCArGIFM) and administered an appropriate amount (1 x 10(8) pfu) of AxCArGIFM on the basis of the optimal dosage determined in a previous study on avulsion of the facial nerve. The administration of AxCArGIFM provided significantly improved histological and biochemical parameters of brain repair compared with controls administered AxCALacZ (adenovirus encoding bacterial beta-galactosidase gene as a reporter; 1 x 10(8) pfu). These results show that GIF can protect from brain damage in certain appropriate conditions in vivo and in vitro. The optimal dosage is very important for the treatment in vivo, particularly that for GIF. Our findings show the double-edged effects of GIF. MTs including MT-III are promising as therapeutic agents not only for tissue repair following acute brain injury, but also for some neurodegenerative diseases because they have multifunctional potential including anti-oxidation effects and may have some effect on neurogenesis.
Neuropathology | 2003
Kazuhiko Watabe; Tsuyoshi Sakamoto; Yoko Kawazoe; Makoto Michikawa; Katsuichi Miyamoto; Takashi Yamamura; Hideyuki Saya; Norie Araki
Previously, the authors have established spontaneously immortalized cell lines from long‐term cultures of normal adult mouse Schwann cells. Establishment of such Schwann cell lines derived from murine disease models may greatly facilitate studies of the cellular mechanisms of their peripheral nervous system lesions in the relevant diseases. Recently, the authors have established immortalized Schwann cell lines derived from Niemann–Pick disease type C mice (NPC; spm/spm) and globoid cell leukodystrophy mice (twitcher). In the present study, long‐term cultures were maintained of Schwann cells derived from dorsal root ganglia and consecutive peripheral nerves of another NPC mouse (npcnih/npcnih, npcnih/+), myelin P0 protein‐deficient mice (P0–/–, P0+/–) with their wild‐type littermates (P0+/+), and neurofibromatosis type 1 gene (NF1)‐deficient mice (Nf1Fcr/+) for 8–10 months, and immortalized cell lines from all these animals established spontaneously. These cell lines had spindle‐shaped Schwann cell morphology and distinct Schwann cell phenotypes and retained genomic and biochemical abnormalities, sufficiently representing the in vivo pathological features of the mutant mice. These immortalized Schwann cell lines can be useful in studies of nervous system lesions in these mutant mice and relevant human disorders.
Journal of The Peripheral Nervous System | 2001
Kazuhiko Watabe; Hiroyuki Ida; Keiko Uehara; Kiyomitsu Oyanagi; Tsuyoshi Sakamoto; Junichi Tanaka; William S. Garver; Shigeki Miyawaki; Kousaku Ohno; Yoshikatsu Eto
Abstract Niemann‐Pick disease type C (NPC) is characterized by an accumulation of unesterified cholesterol in the endosomal/lysosomal (E/L) system, resulting in progressive neurodegeneration and death during early childhood. To investigate the cellular pathomechanism of nervous system involvement in NPC, continuous neural cell lines are desirable. In this study, we obtained neuronal and Schwann cell cultures and established spontaneously immortalized Schwann cell lines from dorsal root ganglia and peripheral nerves of NPC model mouse (spm/spm). One of the cell lines, designated SPMS9, had distinct Schwann cell phenotypes and was maintained over 10 months without phenotypic alterations. The level of Npc1 mRNA was markedly decreased, and NPC1 protein was not detectable in SPMS9 cells. These cells contained intracytoplasmic granules positive for filipin cholesterol staining and immunoreactive for GM2 ganglioside. Electron‐microscopically, intracytoplasmic polymorphous membranous inclusions and vacuoles were demonstrated in SPMS9 cells. The treatment with an inhibitor of ceramide‐specific glucosyltransferase, N‐butyldeoxynojirimysin (NB‐DNJ) markedly reduced the intracytoplasmic granular immunofluorescence for GM2 ganglioside in SPMS9 cells, whereas the amount of filipin‐positive granules remained unchanged. The SPMS9 cells retained vesicular fluorescence of cationic dye acriflavine 16–24 hours after loading, indicating the defect of transmembrane efflux pump activity of NPC1 in the E/L compartment in these cells. These immortalized Schwann cells can be useful in studies on the nervous system lesions in NPC.
Brain Research | 2006
Y.K. Hayashi; Yoko Kawazoe; Tsuyoshi Sakamoto; Miyoko Ojima; Wei Wang; Takanori Takazawa; Daisuke Miyazawa; Wakana Ohya; Hiroshi Funakoshi; Toshikazu Nakamura; Kazuhiko Watabe
Hepatocyte growth factor (HGF) exhibits strong neurotrophic activities on motoneurons both in vitro and in vivo. We examined survival-promoting effects of an adenoviral vector encoding human HGF (AxCAhHGF) on injured adult rat motoneurons after peripheral nerve avulsion. The production of HGF in COS1 cells infected with AxCAhHGF and its bioactivity were confirmed by ELISA, Western blot and Madin-Darby canine kidney (MDCK) cell scatter assay. The facial nerve or the seventh cervical segment (C7) ventral and dorsal roots of 3-month-old Fischer 344 male rats were then avulsed and removed from the stylomastoid or vertebral foramen, respectively, and AxCAhHGF, AxCALacZ (adenovirus encoding beta-galactosidase gene) or phosphate-buffered saline (PBS) was inoculated in the lesioned foramen. Treatment with AxCAhHGF after avulsion significantly prevented the loss of injured facial and C7 ventral motoneurons as compared to AxCALacZ or PBS treatment and ameliorated choline acetyltransferase immunoreactivity in these neurons. These results indicate that HGF may prevent the degeneration of motoneurons in adult humans with motoneuron injury and motor neuron diseases.
Journal of Neuroscience Research | 2005
Ken Ikeda; Masashi Aoki; Yoko Kawazoe; Tsuyoshi Sakamoto; Y.K. Hayashi; Aya Ishigaki; Makiko Nagai; Rieko Kamii; Shinsuke Kato; Yasuto Itoyama; Kazuhiko Watabe
We investigated motoneuron degeneration after proximal nerve injury in presymptomatic transgenic (tg) rats expressing human mutant Cu/Zn superoxide dismutase (SOD1). The right facial nerves of presymptomatic tg rats expressing human H46R or G93A SOD1 and their non‐tg littermates were avulsed, and facial nuclei were examined at 2 weeks postoperation. Nissl‐stained cell counts revealed that facial motoneuron loss after avulsion was exacerbated in H46R‐ and G93A‐tg rats compared with their non‐tg littermates. The loss of motoneurons in G93A‐tg rats after avulsion was significantly greater than that in H46R‐tg rats. Intense cytoplasmic immunolabeling for SOD1 in injured motoneurons after avulsion was demonstrated in H46R‐ and G93A‐tg rats but not in their littermates. Facial axotomy did not induce significant motoneuron loss nor enhance SOD1 immunoreactivity in these tg rats and non‐tg littermates at 2 weeks postoperation, although both axotomy and avulsion elicited intense immunolabeling for activating transcription factor‐3, phosphorylated c‐Jun, and phosphorylated heat shock protein 27 in injured motoneurons of all these animals. The present data indicate the increased vulnerability of injured motoneurons after avulsion in the presymptomatic mutant SOD1‐tg rats.
Muscle & Nerve | 2009
Takashi Shimoyama; Yohei Tamura; Tsuyoshi Sakamoto; Kiyoharu Inoue
We report a patient with uncontrolled Crohns disease who presented with progressive weakness of proximal muscles and a marked elevation of serum creatine kinase. Muscle biopsy from the left deltoid exhibited myositic changes with inflammatory infiltrates in the perimysium, endomysium, and perivascular locations. Most were stained as CD68‐positive macrophages, whereas some were CD4‐ and CD8‐positive T lymphocytes. Due to uncontrolled bowel inflammation, several fistulae were found in the descending colon, and partial colectomy was performed. An examination of the resected colon exhibited inflammation of the bowel structure surrounded mainly by CD68‐positive macrophages. The histopathological findings of the descending colon were analogous to those of the muscle. After an increased dose of mesalazine and partial colectomy, her muscle symptoms improved. These findings suggest that the myositis in Crohns disease is immune‐mediated and that treatment of bowel inflammation should be emphasized as opposed to steroid or other immunosuppressive therapy.