Jiro Kasahara, Mohammed Emamussalehin Choudhury, Hironori Yokoyama, Naoto Kadoguchi and Masahiro Nomoto : Animal Models for the Study of Human Disease (Edited by Conn PM), --- Part VII: The Brain, Stroke, and Neuromuscular, Chapter 26: Neurotoxin 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Induced Animal Models for Parkinson's Disease ---, Academic Press, Jul. 2013.
Yukuto Ogawa, Sohei Tsugita, Yuka Torii, Hiten Iwamoto, Tsukasa Sato, Jiro Kasahara, Masaki Takeuchi, Tomohiko Kuwabara, Masamitsu Iiyama, Toshio Takayanagi and Hitoshi Mizuguchi : Microdialysis-integrated HPLC system with dual-electrode detection using track-etched membrane electrodes for in vivo monitoring of dopamine dynamics, Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences, Vol.1247, 124318, 2024.
(要約)
A capillary high-performance liquid chromatography (HPLC) system equipped with a dual-electrode detector utilizing track-etched membrane electrodes (TEMEs) was combined with a microdialysis sampling setup. The electrochemical detector benefits from the high electrolysis efficiency of TEMEs, allowing for calibration-free coulometric detection and simplifying data analysis to determine the dopamine recovery through a dialysis probe. Additionally, this system was used for in vivo monitoring of dopamine in the right striatum of a mouse brain. Temporal changes in dopamine levels, including an exponential decay immediately after the dialysis probe insertion and an excess release of dopamine induced by a high concentration of potassium ions, confirmed the system's proper operation. Furthermore, subsequent measurements following the intraperitoneal injection of mirtazapine showed no increase in dopamine levels in the right dorsal striatum. The dual-electrode system displayed characteristic dopamine detection behavior, with anodic and cathodic peak pairs indicative of reversible electrochemical reactions. This capability facilitated the identification of the dopamine peak within the complex chromatogram of the mouse brain dialysate. The consistency between dopamine collection efficiency from standard solutions and dialysate indicated the absence of interfering electroactive substances overlapping with the dopamine peak in the chromatogram. This integrated analysis system successfully tracked temporal fluctuations in dopamine concentration within the mouse brain.
Masatoshi Ogawa, Yu Zhou, Ryosuke Tsuji, Jiro Kasahara and Satoshi Goto : Intrastriatal Memantine Infusion Dampens Levodopa-Induced Dyskinesia and Motor Deficits in a Mouse Model of Hemiparkinsonism, Frontiers in Neurology, No.10, 1258, 2019.
(要約)
Although the administration of dopamine precursor levodopa remains as the mainstay for the treatment of Parkinson's disease, long-term exposure to levodopa often causes a disabling complication, referred to as levodopa-induced dyskinesias. Therefore, the development of new therapeutic interventions to dampen levodopa-induced dyskinesias and parkinsonian motor deficits is needed in the treatment of Parkinson's disease. Intracerebral brain infusion has the merit of being able to specifically deliver any drug into any brain part. By using an intracerebral infusion system equipped with implantable, programmable, and refillable pumps, we show herein that continuous intrastriatal administration of memantine (MMT), which is a non-competitive N-methyl-D-aspartate receptor antagonist, attenuates levodopa-induced dyskinesias and parkinsonian signs in 6-hydroxydopamine-lesioned hemiparkinsonian mice that received daily levodopa treatment. Corroborating the general thought that overactivation of the striatal N-methyl-D-aspartate receptor function might generate levodopa-induced dyskinesias and parkinsonism, our results suggest that a continuous intrastriatal MMT infusion can be beneficial for the management of Parkinson's disease with levodopa-induced dyskinesias. Our study also provides indications for the prototypic use of pharmacological deep-brain modulation through intracerebral infusion systems for treating medically intractable movement disorders.
Kazuhisa Miyake, Ayuko Sakane, Ikuko Sagawa, Yoko Tomida, Jiro Kasahara and Takuya Sasaki : Actin Cytoskeletal Reorganization Function of JRAB/MICAL-L2 Is Fine-tuned by Intramolecular Interaction between First LIM Zinc Finger and C-terminal Coiled-coil Domains, Scientific Reports, Vol.9, No.1, 12794, 2019.
(要約)
JRAB/MICAL-L2 is an effector protein of Rab13, a member of the Rab family of small GTPase. JRAB/MICAL-L2 consists of a calponin homology domain, a LIM domain, and a coiled-coil domain. JRAB/MICAL-L2 engages in intramolecular interaction between the N-terminal LIM domain and the C-terminal coiled-coil domain, and changes its conformation from closed to open under the effect of Rab13. Open-form JRAB/MICAL-L2 induces the formation of peripheral ruffles via an interaction between its calponin homology domain and filamin. Here, we report that the LIM domain, independent of the C-terminus, is also necessary for the function of open-form JRAB/MICAL-L2. In mechanistic terms, two zinc finger domains within the LIM domain bind the first and second molecules of actin at the minus end, potentially inhibiting the depolymerization of actin filaments (F-actin). The first zinc finger domain also contributes to the intramolecular interaction of JRAB/MICAL-L2. Moreover, the residues of the first zinc finger domain that are responsible for the intramolecular interaction are also involved in the association with F-actin. Together, our findings show that the function of open-form JRAB/MICAL-L2 mediated by the LIM domain is fine-tuned by the intramolecular interaction between the first zinc finger domain and the C-terminal domain.
Masatoshi Ogawa, Zhou Yu, Ryosuke Tsuji, Satoshi Goto and Jiro Kasahara : Video-based assessmens of the hind limb stepping in a mouse model of hemi-parkinsonism., Neuroscience Research, Vol.154, 56-59, 2019.
(要約)
Unilateral injection of 6-hydroxydopamine (6-OHDA) is commonly used to generate a rodent model of Parkinson's disease (PD). Although motor deficits of the lower extremities represent one of the major clinical symptoms in PD patients, validated tests for assessing motor impairments of the hind limb in 6-OHDA mice are currently unavailable. We here report the video-based assessments of the asymmetric use of hind limbs in 6-OHDA mice. A significantly decreased number of spontaneous hind limb stepping was observed in the contralateral-to-lesioned side, and was dose dependently reversed by levodopa, suggesting that it could be utilized for screening PD therapeutics.
Yu Zhou, Yukio Yamamura, Masatoshi Ogawa, Ryosuke Tsuji, Koichiro Tsuchiya, Jiro Kasahara and Satoshi Goto : c-Abl inhibition exerts symptomatic antiparkinsonian effects through a striatal postsynaptic mechanism., Frontiers in Pharmacology, Vol.9, 1311, 2018.
(要約)
Parkinson's disease (PD) is caused by a progressive degeneration of nigral dopaminergic cells leading to striatal dopamine deficiency. From the perspective of antiparkinsonian drug mechanisms, pharmacologic treatment of PD can be divided into symptomatic and disease-modifying (neuroprotective) therapies. An increase in the level and activity of the Abelson non-receptor tyrosine kinase (c-Abl) has been identified in both human and mouse brains under PD conditions. In the last decade, it has been observed that the inhibition of c-Abl activity holds promise for protection against the degeneration of nigral dopaminergic cells in PD and thereby exerts antiparkinsonian effects. Accordingly, c-Abl inhibitors have been applied clinically as a disease-modifying therapeutic strategy for PD treatment. Moreover, in a series of studies, including that presented here, experimental evidence suggests that in a mouse model of parkinsonism induced by -methyl-4-phenyl-1,2,3,6-tetrahydropyridine, c-Abl inhibition exerts an immediate effect improving motor impairments by normalizing altered activity in striatal postsynaptic signaling pathways mediated by Cdk5 (cyclin-dependent kinase 5) and DARPP-32 (dopamine- and cyclic AMP-regulated phosphoprotein 32 kDa). Based on this, we suggest that c-Abl inhibitors represent an ideal antiparkinsonian agent that has both disease-modifying and symptomatic effects. Future research is required to carefully evaluate the therapeutic efficacy and clinical challenges associated with applying c-Abl inhibitors to the treatment of PD.
Jiro Kasahara, Hiroto Uchida, Kenta Tezuka and Nanae Oka : Postischemic anhedonia associated with neurodegenerative changes in the hippocampal dentate gyrus of rats, Neural Plasticity, Vol.2016, No.2016, 5054275, 2016.
We demonstrate that activation-induced manganese-enhanced magnetic resonance imaging with quantitative determination of the longitudinal relaxation time (qAIM-MRI) reveals the severity of Parkinson's disease (PD) in mice. We first show that manganese ion-accumulation depends on neuronal activity. A highly active region was then observed by qAIM-MRI in the caudate-putamen in PD-model mice that was significantly correlated to the severity of PD, suggesting its involvement in the expression of PD symptoms.
Naoto Kadoguchi, Shinji Okabe, Yukio Yamamura, Misaki Shono, Fukano T, Akie Tanabe, Hironori Yokoyama and Jiro Kasahara : Mirtazapine has a therapeutic potency in 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP)-induced mice model of Parkinson's disease, BMC Neuroscience, Vol.15, No.79, 2014.
(要約)
Mirtazapine, a noradrenergic and specific serotonergic antidepressant (NaSSA), shows multiple pharmacological actions such as inhibiting presynaptic α2 noradrenaline receptor (NAR) and selectively activating 5-hydroxytriptamine (5-HT) 1A receptor (5-HT1AR). Mirtazapine was also reported to increase dopamine release in the cortical neurons with 5-HT dependent manner. To examine whether mirtazapine has a therapeutic potency in Parkinson's disease (PD), we examined this compound in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice model of PD. Male C57BL/6 mice were subjected to MPTP treatment to establish a PD model. Mirtazapine was administered once a day for 3 days after MPTP treatment. MPTP-induced motor dysfunction, assessed by beam-walking and rota-rod tests, was significantly improved by administration of mirtazapine. Biochemical examinations by high performance liquid chromatography and western blot analysis suggested mirtazapine facilitated utilization of dopamine by increasing turnover and protein expression of transporters, without affecting on neurodegenerative process by MPTP. These therapeutic effects of mirtazapine were reduced by administration of WAY100635, an inhibitor for 5HT1AR, or of clonidine, a selective agonist for α2-NAR, or of prazosin, an inhibitor for α1-NAR, respectively. Our results showed mirtazapine had a therapeutic potency against PD in a mouse model. Because PD patients sometimes show depression together, it will be a useful drug for a future PD treatment.
Akie Tanabe, Yukio Yamamura, Jiro Kasahara, Ryoma Morigaki, Ryuji Kaji and Satoshi Goto : A novel tyrosine kinase inhibitor AMN107 (nilotinib) normalizes striatal motor behaviors in a mouse model of Parkinson's disease., Frontiers in Cellular Neuroscience, Vol.8, No.50, 2014.
(要約)
Abnormal motor behaviors in Parkinson's disease (PD) result from striatal dysfunction due to an imbalance between dopamine and glutamate transmissions that are integrated by dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32). c-Abelson tyrosine kinase (c-Abl) phosphorylates cyclin-dependent kinase 5 (Cdk5) at Tyr15 to increase the activity of Cdk5, which reduces the efficacy of dopaminergic signaling by phosphorylating DARPP-32 at Thr75 in the striatum. Here, we report that in the mouse striatum, a novel c-Abl inhibitor, nilotinib (AMN107), inhibits phosphorylation of both Cdk5 at Tyr15 and DARPP-32 at Thr75, which is negatively regulated by dopamine receptor activation through a D2 receptor-mediated mechanism. Like a D2-agonist, nilotinib synergizes with a D1-agonist for inducing striatal c-Fos expression. Moreover, systemic administration of nilotinib normalizes striatal motor behaviors in a mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. These findings suggest that nilotinib could possibly serve as a new and alternative agent for treating PD motor symptoms.
Yukio Yamamura, Ryoma Morigaki, Jiro Kasahara, Hironori Yokoyama, Akie Tanabe, Shinya Ohkita, Hidetaka Koizumi, Shinji Nagahiro, Ryuji Kaji and Satoshi Goto : Dopamine signaling negatively regulates striatal phosphorylation of Cdk5 at tyrosine 15 in mice, Frontiers in Cellular Neuroscience, Vol.7, No.12, 1-10, 2013.
(要約)
Striatal functions depend on the activity balance between the dopamine and glutamate neurotransmissions. Glutamate inputs activate cyclin-dependent kinase 5 (Cdk5), which inhibits postsynaptic dopamine signaling by phosphorylating DARPP-32 (dopamine- and cAMP-regulated phosphoprotein, 32 kDa) at Thr75 in the striatum. c-Abelson tyrosine kinase (c-Abl) is known to phosphorylate Cdk5 at Tyr15 (Tyr15-Cdk5) and thereby facilitates the Cdk5 activity. We here report that Cdk5 with Tyr15 phosphorylation (Cdk5-pTyr15) is enriched in the mouse striatum, where dopaminergic stimulation inhibited phosphorylation of Tyr15-Cdk5 by acting through the D2 class dopamine receptors. Moreover, in the 1-methyl-4-phenyl-1,2,4,6-tetrahydropyridine (MPTP) mouse model, dopamine deficiency caused increased phosphorylation of both Tyr15-Cdk5 and Thr75-DARPP-32 in the striatum, which could be attenuated by administration of L-3,4-dihydroxyphenylalanine and imatinib (STI-571), a selective c-Abl inhibitor. Our results suggest a functional link of Cdk5-pTyr15 with postsynaptic dopamine and glutamate signals through the c-Abl kinase activity in the striatum.
Ryoma Morigaki, Wataru Sako, Shinya Okita, Jiro Kasahara, Hironori Yokoyama, Shinji Nagahiro, Ryuji Kaji and Satoshi Goto : Cyclin-dependent kinase 5 with phosphorylation of tyrosine 15 residue is enriched in striatal matrix compartment in adult mice, Neuroscience, Vol.189, 25-31, 2011.
(要約)
Accumulating evidence suggests that the striosome-matrix systems have a tight link with motor and behavioral brain functions and their disorders. Cyclin-dependent kinase 5 (Cdk5) is a versatile protein kinase that plays a role in synaptic functions and cell survival in adult brain, and its kinase activity is stimulated by phosphorylation at tyrosine 15 residue (pY15). In this study, we used an immunohistochemical method to show differential localization of Cdk5-pY15 in the striatal compartments of adult mice, with a heightened density of Cdk5-pY15 labeling in the matrix relative to the striosomes. Our findings indicate that Cdk5-pY15 can be a new marker for the striatal matrix compartment, and suggest a possible involvement of Cdk5-mediated signaling in compartment-specific neurotransmission and disease pathology in the striatum.
Hironori Yokoyama, Hayato Kuroiwa, Jiro Kasahara and Tsutomu Araki : Neuropharmacological approach against MPTP (1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine)-induced mouse model of Parkinson's disease., Acta Neurobiologiae Experimentalis, Vol.71, No.2, 269-280, 2011.
(要約)
Parkinson's disease (PD) is a common neurodegenerative disease that appears essentially as a sporadic condition. PD is well known to be a chronic and progressive neurodegenerative disease produced by a selective degeneration of dopaminergic neurons in the substantia nigra pars compacta. The main clinical features of PD include tremor, bradykinesia, rigidity and postural instability. Most insights into pathogenesis of PD come from investigations performed in experimental models of PD, especially those produced by neurotoxins. The biochemical and cellular alterations that occur after 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP) treatment are remarkably similar to that observed in idiopathic PD. Furthermore, it is well known that acute treatment with MPTP can cause a severe loss of tyrosine hydroxylase and dopamine transporter protein levels and dopamine contents in the striatum of mice, as compared to continuous MPTP treatment. Thus these findings may support the validity of acute MPTP treatment model for unraveling in the neurodegenerative processes in PD. In this review, we discuss the neuroprotective effects of various compounds against neuronal cell loss in an MPTP model of PD. This review may lead to a much better understanding of PD as well as provide novel clues to new targets for therapeutic interventions in PD patients.
(キーワード)
Animals / Antiparkinson Agents / Corpus Striatum / Disease Models, Animal / Dopamine / Dose-Response Relationship, Drug / Drug Interactions / Glial Fibrillary Acidic Protein / Mice / Models, Biological / Parkinsonian Disorders / Time Factors / Tyrosine 3-Monooxygenase
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 21731080
Hironori Yokoyama, Hiroto Uchida, Hayato Kuroiwa, Jiro Kasahara and Tsutomu Araki : Role of glial cells in neurotoxin-induced animal models of Parkinson's disease., Neurological Sciences, Vol.32, No.1, 1-7, 2011.
(要約)
Dopaminergic neurons are selectively vulnerable to oxidative stress and inflammatory attack. The neuronal cell loss in the substantia nigra is associated with a glial response composed markedly of activated microglia and, to a lesser extent, of reactive astrocytes although these glial responses may be the source of neurotrophic factors and can protect against oxidative stress such as reactive oxygen species and reactive nitrogen species. However, the glial response can also mediate a variety of deleterious events related to the production of pro-inflammatory, pro-oxidant reactive species, prostaglandins, cytokines, and so on. In this review, we discuss the possible protective and deleterious effects of glial cells in the neurodegenerative diseases and examine how these factors may contribute to the pathogenesis of Parkinson's disease. This review suggests that further investigation concerning glial reaction in Parkinson's disease may lead to disease-modifying therapeutic approaches and may contribute to the pathogenesis of this disease.
Minami Adachi, Manami Abe, Taeko Sasaki, Hiroyuki Kato, Jiro Kasahara and Tsutomu Araki : Role of inducible or neuronal nitric oxide synthase in neurogenesis of the dentate gyrus in aged mice, Metabolic Brain Disease, Vol.25, 419-424, 2010.
(要約)
We evaluated mainly the iNOS (inducible nitric oxide synthase) and nNOS (neuronal NOS) expression in the subgranular zone (SGZ) of the dentate gyrus of the hippocampus in young adult (8-week-old) and aged (60-week-old) mice. The present study demonstrates that the expression of nNOS was more pronounced than that of iNOS expression in the dentate gyrus of aged mice. Our study also suggests that aged mice exhibited a significant loss of motor activity as compared with young adult animals. Furthermore, our results provide that no significant change in the number of Neu N (Neuronal nuclei)-immunopositive neurons and GFAP (glial fibrillary acidic protein)-immunopositive astrocytes was observed in the dentate gyrus between young adult and aged mice. In contrast, a significant change in the number of Iba 1(ionized calcium-binding adaptor molecule 1)-immunopositive microglia in aged mice was observed in the dentate gyrus as compared to young adult animals. These results provide the novel evidence showing that the expression of nNOS may be crucial for the role of neurogenesis of the SGZ of the dentate gyrus in aged mice. Furthermore, our present findings demonstrate that the inhibition of nNOS expression in the SGZ of the dentate gyrus during aging processes may offer novel therapeutic strategies for anti-aging in humans.
(キーワード)
Aging / Animals / Calcium-Binding Proteins / Dentate Gyrus / Glial Fibrillary Acidic Protein / Immunohistochemistry / Locomotion / Male / Mice / Mice, Inbred ICR / Mice, Knockout / Microglia / Nerve Tissue Proteins / Neurogenesis / Neurons / Nitric Oxide Synthase Type I / Nitric Oxide Synthase Type II / Nuclear Proteins / Postural Balance
R Eto, M Abe, H Kimoto, E Imaoka, H Kato, Jiro Kasahara and Tsutomu Araki : Alterations of interneurons in the striatum and frontal cortex of mice during postnatal development, International Journal of Developmental Neuroscience, Vol.28, No.5, 359-370, 2010.
(要約)
We investigated the postnatal alterations of neuronal nuclei (NeuN)-positive neurons, parvalbumin (PV)-positive interneurons, neuronal nitric oxide synthase (nNOS)-positive interneurons, and neurotrophic factors in the mouse striatum and frontal cortex using immunohistochemistry. NeuN, PV, nNOS, nerve growth factor (NGF), and brain-derived neurotrophic factor (BDNF) immunoreactivity were measured in 1-, 2-, 4- and 8-week-old mice. Total number of NeuN-positive neurons was unchanged in the mouse striatum and frontal cortex from 1 up to 8 weeks of age. In contrast, a significant decrease in the number of PV-positive interneurons was observed in the striatum and frontal cortex of 1-, 2- and 4-week-old mice. Furthermore, a significant increase of nNOS-positive interneurons was found in the striatum and frontal cortex of 1- and/or 2-week-old mice. NGF-positive neurons were unchanged in the mouse striatum from 1 up to 8 weeks of age. In the frontal cortex, a significant increase in the number of NGF-positive neurons was observed only in 1-week-old mice. In contrast, a significant increase in the number of NGF-positive glia 1 cells was found in the striatum and frontal cortex of 4-week-old mice. Our double-labeled immunostaining showed that nNOS immunoreactivity was not found in PV-immunopositive interneurons. Furthermore, BDNF immunoreactivity was observed in both nNOS-positive and PV-positive interneurons in the striatum of 1- or 2-week-old mice. These results show that the maturation of nNOS-immunopositive interneurons precedes the maturation of PV-immunopositive interneurons in the striatum and frontal cortex during postnatal development. Furthermore, our results demonstrate that the expression of BDNF may play some role in the maturation of interneurons in the striatum and frontal cortex during postnatal development. Moreover, our findings suggest that the expression of NGF in glia cells may play some role in the maturation of glial cells and PV-positive interneurons in the striatum and frontal cortex during postnatal development.
M Abe, H Kimoto, R Eto, T Sasaki, H Kato, Jiro Kasahara and Tsutomu Araki : Postnatal Development of Neurons, Interneurons and Glial Cells in the Substantia Nigra of Mice, Cellular and Molecular Neurobiology, Vol.30, No.6, 917-928, 2010.
(要約)
We investigated postnatal alterations of neurons, interneurons and glial cells in the mouse substantia nigra using immunohistochemistry. Tyrosine hydroxylase (TH), neuronal nuclei (NeuN), parvalbumin (PV), neuronal nitric oxide synthase (nNOS), glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor molecule 1 (Iba 1), CNPase (2',3'-cyclic nucleotide 3'-phosphodiesterase), brain-derived neurotrophic factor (BDNF) and glial cell-line-derived neurotrophic factor (GDNF) immunoreactivity were measured in 1-, 2-, 4- and 8-week-old mice. In the present study, the maturation of NeuN-immunopositive neurons preceded the production of TH in the substantia nigra during postnatal development in mice. Furthermore, the maturation of nNOS-immunopositive interneurons preceded the maturation of PV-immunopositive interneurons in the substantia nigra during postnatal development. Among astrocytes, microglia and oligodendrocytes, in contrast, the development process of oligodendrocytes is delayed in the substantia nigra. Our double-labeled immunohistochemical study suggests that the neurotrophic factors such as BDNF and GDNF secreted by GFAP-positive astrocytes may play some role in maturation of neurons, interneurons and glial cells of the substantia nigra during postnatal development in mice. Thus, our findings provide valuable information on the development processes of the substantia nigra.
H Uchida, Y Fujita, M Matsueda, M Umeda, S Matsuda, H Kato, Jiro Kasahara and Tsutomu Araki : Damage to Neurons and Oligodendrocytes in the Hippocampal CA1 Sector after Transient Focal Ischemia in Rats, Cellular and Molecular Neurobiology, Vol.30, No.7, 1125-1134, 2010.
(要約)
Focal brain lesions such as transient focal cerebral ischemia can lead to neuronal damage in remote areas, including the ipsilateral substantia nigra and hippocampus, as well as in the ischemic core. In this study, we investigated acute changes in the ipsilateral hippocampus from 1 up to 7 days after 90 min of transient focal cerebral ischemia in rats, using anti-NeuN (neuronal nuclei), anti-Cu/Zn-superoxide dismutase (Cu/Zn-SOD), anti-Mn-SOD, anti-neuronal nitric oxide synthase (nNOS), anti-inducible NOS (iNOS), anti-glial fibrillary acidic protein (GFAP), anti-ionized calcium-binding adaptor molecule 1(Iba 1) and anti-2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) antibodies. In our western blot and histochemical analyses, present results show that transient focal cerebral ischemia in rats can cause a severe and acute damage of neurons and oligodendrocytes in the ipsilateral hippocampal CA1 sector. The present findings also demonstrate that the expression of iNOS produced by Iba 1-immunopositive microglia precedes the damage of neurons and oligodendrocytes in the ipsilateral hippocampal CA1 sector after transient focal cerebral ischemia. In contrast, our results suggest that increased reactive oxygen species (ROS) production during reperfusion cannot lead to damage of neurons and oligodendrocytes in the ipsilateral hippocampal CA1 sector after transient focal cerebral ischemia, because of an insufficient expression of Cu/Zn-SOD and Mn-SOD. Our double-labeled immunohistochemical study demonstrates that the overexpression of iNOS produced by Iba 1-immunopositive microglia may play a pivotal role in the damage of neurons and oligodendrocytes in the ipsilateral hippocampal CA1 sector at an acute stage after transient focal cerebral ischemia.
(キーワード)
2',3'-Cyclic-Nucleotide Phosphodiesterases / Animals / CA1 Region, Hippocampal / Calcium-Binding Proteins / Glial Fibrillary Acidic Protein / Ischemic Attack, Transient / Isoenzymes / Male / Microfilament Proteins / Neurons / Nitric Oxide Synthase Type I / Nitric Oxide Synthase Type II / Oligodendroglia / Rats / Rats, Sprague-Dawley / Superoxide Dismutase
Hironori Yokoyama, Ryohei Yano, Hayato Kuroiwa, Tatsuya Tsukada, Hiroto Uchida, Hiroyuki Kato, Jiro Kasahara and Tsutomu Araki : Therapeutic effect of a novel anti-parkinsonian agent zonisamide against MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)neurotoxicity in mice., Metabolic Brain Disease, Vol.25, No.2, 135-143, 2010.
(要約)
We investigated the therapeutic effect of zonisamide against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity in mice, using Western blot analysis, immunohistochemistry and behavioral test. Our Western blot analysis and immunohistochemical study showed that the post-treatment with zonisamide prevented significantly dopaminergic cell damage, the depletion of tyrosine-hydroxylase (TH) protein levels and the proliferation of microglia in the striatum and/or substantia nigra 8 days after MPTP treatment. Furthermore, our behavioral study showed that the post-treatment with zonisamide attenuated significantly the motor deficits 7 days after MPTP treatment. These results show that zonisamide has the therapeutic effect in the MPTP model of Parkinson's disease (PD) in mice. Our study also demonstrates the neuroprotective effect of zonisamide against dopaminergic cell damage after MPTP treatment in mice. Thus our present findings suggest that therapeutic strategies targeted to the activation of TH protein and/or the inhibition of microglial activation with zonisamide may offer a great potential for restoring the functional capacity of the surviving dopaminergic neurons in individuals affected with PD.
Calcium-calmodulin dependent protein kinase IV (CaMKIV) is a protein kinase that activates the transcription factor CREB, the cyclic AMP-response element binding protein. CREB is a key transcription factor in synaptic plasticity and memory consolidation. To elucidate the behavioral effects of CaMKIV deficiency, we subjected CaMKIV knockout (CaMKIV KO) mice to a battery of behavioral tests. CaMKIV KO had no significant effects on locomotor activity, motor coordination, social interaction, pain sensitivity, prepulse inhibition, attention, or depression-like behavior. Consistent with previous reports, CaMKIV KO mice exhibited impaired retention in a fear conditioning test 28 days after training. In contrast, however, CaMKIV KO mice did not show any testing performance deficits in passive avoidance, one of the most commonly used fear memory paradigms, 28 days after training, suggesting that remote fear memory is intact. CaMKIV KO mice exhibited intact spatial reference memory learning in the Barnes circular maze, and normal spatial working memory in an eight-arm radial maze. CaMKIV KO mice also showed mildly decreased anxiety-like behavior, suggesting that CaMKIV is involved in regulating emotional behavior. These findings indicate that CaMKIV might not be essential for fear memory or spatial memory, although it is possible that the activities of other neural mechanisms or signaling pathways compensate for the CaMKIV deficiency.
Miyohiko Takemura, Toshiaki Mishima, Yan Wang, Jiro Kasahara, Kohji Fukunaga, Kazumasa Ohashi and Kensaku Mizuno : Ca2+/calmodulin-dependent protein kinase IV-mediated LIM kinase activation is critical for calcium signal-induced neurite outgrowth., The Journal of Biological Chemistry, Vol.284, No.42, 28554-28562, 2009.
(要約)
Actin cytoskeletal remodeling is essential for neurite outgrowth. LIM kinase 1 (LIMK1) regulates actin cytoskeletal remodeling by phosphorylating and inactivating cofilin, an actin filament-disassembling factor. In this study, we investigated the role of LIMK1 in calcium signal-induced neurite outgrowth. The calcium ionophore ionomycin induced LIMK1 activation and cofilin phosphorylation in Neuro-2a neuroblastoma cells. Knockdown of LIMK1 or expression of a kinase-dead mutant of LIMK1 suppressed ionomycin-induced cofilin phosphorylation and neurite outgrowth in Neuro-2a cells. Ionomycin-induced cofilin phosphorylation and neurite outgrowth were also blocked by KN-93, an inhibitor of Ca(2+)/calmodulin-dependent protein kinases (CaMKs), and STO-609, an inhibitor of CaMK kinase. An active form of CaMKIV but not CaMKI enhanced Thr-508 phosphorylation of LIMK1 and increased the kinase activity of LIMK1. Moreover, the active form of CaMKIV induced cofilin phosphorylation and neurite outgrowth, and a dominant negative form of CaMKIV suppressed ionomycin-induced neurite outgrowth. Taken together, our results suggest that LIMK1-mediated cofilin phosphorylation is critical for ionomycin-induced neurite outgrowth and that CaMKIV mediates ionomycin-induced LIMK1 activation.
Shenuarin Md Bhuiyan, Yoko Takada, Norifumi Shioda, Shigeki Moriguchi, Jiro Kasahara and Kohji Fukunaga : Cardioprotective effect of vanadyl sulfate on ischemia/reperfusion-induced injury in rat heart in vivo is mediated by activation of protein kinase B and induction of FLICE-inhibitory protein., Cardiovascular Therapeutics, Vol.26, No.1, 10-23, 2008.
(要約)
Here we explored the mechanism of cardioprotective action of a tyrosine phosphatase inhibitor vanadyl sulfate on myocardial infarction and cardiac functional recovery in rats subjected to myocardial ischemia/reperfusion (MI/R) in vivo. Male Sprague-Dawley rats underwent 30 min heart ischemia by left coronary artery occlusion followed by 24-h reperfusion. Rats were randomized to receive either vehicle or vanadyl sulfate (1 and 5 mg/kg) intraperitoneally 0 min and 30 min after the start of reperfusion. Posttreatment with vanadyl sulfate significantly reduced the infarct size and significantly decreased the elevated left ventricular end diastolic pressure, improved left ventricular developed pressure, and left ventricular contractility (+/- dP/dt) after 72-h reperfusion in a dose-dependent manner. Moreover, treatment with vanadyl sulfate also significantly inhibited the apoptosis-related Caspase-3 and Caspase-9 processing, thereby elicited the antiapoptotic effect. The cardioprotective effect of vanadyl sulfate was closely associated with restoration of reduced protein kinase B (Akt) activity following MI/R injury. The recovered Akt activity correlated with increased phosphorylation of forkhead transcription factors, FKHR and FKHRL-1, thereby inhibiting apoptotic signaling. Furthermore, treatment with vanadyl sulfate significantly increased FLICE-inhibitory protein (FLIP) expression, and decreased expression of Fas ligand and Bim in cardiomyocytes. Taken together, rescue of cardiomyocytes by posttreatment with vanadyl sulfate from MI/R injury was mediated by increased FLIP expression and decreased Fas ligand and Bim expression via activation of Akt. These results demonstrate that treatment with vanadyl sulfate exerts significant cardioprotective effects along with cardiac functional recovery.
(キーワード)
Animals / Apoptosis / Blood Pressure / Blotting, Western / CASP8 and FADD-Like Apoptosis Regulating Protein / Cardiotonic Agents / Caspases / Cell Survival / Enzyme Activation / Fas Ligand Protein / Forkhead Transcription Factors / Heart Rate / Injections, Intraperitoneal / Male / Myocardial Reperfusion Injury / Myocardium / Oncogene Protein v-akt / Protein Tyrosine Phosphatases / Proto-Oncogene Proteins c-akt / Rats / Rats, Sprague-Dawley / Rats, Wistar / Signal Transduction / Vanadium Compounds
Ying-Mei Lu, Norifumi Shioda, Feng Han, Shigeki Moriguchi, Jiro Kasahara, Yasufumi Shirasaki, Zheng-Hong Qin and Kohji Fukunaga : Imbalance between CaM kinase II and calcineurin activities impairs caffeine-induced calcium release in hypertrophic cardiomyocytes., Biochemical Pharmacology, Vol.74, No.12, 1727-1737, 2007.
(要約)
Cardiac hypertrophy impairs Ca(2+) handling in the sarcoplasmic reticulum, thereby impairing cardiac contraction. To identify the mechanisms underlying impaired Ca(2+) release from the sarcoplasmic reticulum in hypertrophic cardiomyocytes, we assessed Ca(2+)-dependent signaling and the phosphorylation of phospholamban, which regulates Ca(2+) uptake during myocardial relaxation and is in turn regulated by Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and calcineurin. In cultured rat cardiomyocytes, treatment with endothelin-1, angiotensin II, and phenylephrine-induced hypertrophy and increased CaMKII autophosphorylation and calcineurin expression. The calcineurin level reached its maximum at 72h and remained elevated for at least 96h after endothelin-1 or angiotensin II treatment. By contrast, CaMKII autophosphorylation, phospholamban phosphorylation, and caffeine-induced Ca(2+) mobilization all peaked 48h after these treatments. By 96h after treatment, CaMKII autophosphorylation and phospholamban phosphorylation had returned to baseline, and caffeine-induced Ca(2+) mobilization was impaired relative to baseline. A similar biphasic change was observed in dystrophin levels in endothelin-1-induced hypertrophic cardiomyocytes, and treatment with the novel CaM antagonists DY-9760e and DY-9836 significantly inhibited the hypertrophy-induced dystrophin breakdown. Taken together, the abnormal Ca(2+) regulation in cardiomyocytes following hypertrophy is in part mediated by an imbalance in calcineurin and CaMKII activities, which leads to abnormal phospholamban activity.
Shenuarin Md Bhuiyan, Masatoshi Shibuya, Norifumi Shioda, Shigeki Moriguchi, Jiro Kasahara, Yosiharu Iwabuchi and Kohji Fukunaga : Cytoprotective effect of bis(1-oxy-2-pyridinethiolato)oxovanadiun(IV) on myocardial ischemia/reperfusion injury elicits inhibition of Fas ligand and Bim expression and elevation of FLIP expression., European Journal of Pharmacology, Vol.571, No.2-3, 180-188, 2007.
(要約)
VO(OPT), bis(1-oxy-2-pyridinethiolato)oxovanadium(IV), has been shown to increase tyrosine phosphorylation of proteins and promote the insulin receptor signaling, thereby elicit anti-diabetic action. We here investigated the cytoprotective action of VO(OPT) on myocardial infarction and cardiac functional recovery in rats subjected to myocardial ischemia/reperfusion and defined mechanisms underlying its cytoprotective action. Rats underwent 30 min myocardial ischemia by left anterior descending coronary artery occlusion followed by 24 h reperfusion. Post-ischemic treatment with VO(OPT) significantly reduced infarct size and improved cardiac function (left ventricular developed pressure and +/-dP/dt) after 72 h reperfusion and in a dose-dependent manner. Moreover, VO(OPT) treatment also dose-dependently significantly inhibited caspases-3, -9 and -7 processing, thereby elicited the anti-apoptotic effect. The cytoprotective effect of VO(OPT) was closely associated with restoration of Akt activity. The recovered Akt activity correlated with increased phosphorylation of Bad and forkhead transcription proteins, thereby inhibiting apoptotic signaling. Furthermore, treatment with VO(OPT) significantly increased FLIP expression, and decreased expression of Fas ligand and Bim in cardiomyocytes. Taken together, cardiomyocytes rescue following post-treatment with VO(OPT) from ischemia/reperfusion injury was mediated by increased FLIP expression and decreased Fas ligand and Bim expression via activation of Akt. These results demonstrate that treatment with VO(OPT) exerts significant cytoprotective effects along with improvement of cardiac functional recovery.
Daniela Tardito, Ettore Tiraboschi, Jiro Kasahara, Giorgio Racagni and Maurizio Popoli : Reduced CREB phosphorylation after chronic lithium treatment is associated with down-regulation of CaM kinase IV in rat hippocampus., The International Journal of Neuropsychopharmacology, Vol.10, No.4, 491-496, 2006.
(要約)
Lithium is widely used in the treatment of bipolar disorder, although its mechanism of action is not fully clear. This study was undertaken to assess the effects of prolonged lithium administration on cAMP responsive element-binding protein (CREB) phosphorylation and CaM kinase IV (CaMKIV), one of the main kinases phosphorylating CREB in neurons following synaptic activation. CREB total protein expression and phosphorylation (Ser133), as well as CaMKIV enzymatic activity, phosphorylation of Thr196 (the activator residue) and kinase expression level were assessed in total homogenates and nuclei from the hippocampus and prefrontal/frontal cortex following 5 wk lithium treatment. Whereas no significant effects were found in prefrontal/frontal cortex, lithium administration reduced CREB phosphorylation and at the same time down-regulated CaMKIV (enzymatic activity, phospho-Thr196 and protein expression level) in cell nuclei from the hippocampus. These data suggest for the first time the involvement of CaMKIV in the mechanism of action of lithium.
(キーワード)
Animals / Antimanic Agents / Calcium-Calmodulin-Dependent Protein Kinase Type 4 / Calcium-Calmodulin-Dependent Protein Kinases / Cell Nucleus / Cyclic AMP Response Element-Binding Protein / Down-Regulation / Hippocampus / Lithium Carbonate / Male / Phosphorylation / Prefrontal Cortex / Rats / Rats, Sprague-Dawley / Time Factors
Takuya Sasaki, Feng Han, Norifumi Shioda, Shigeki Moriguchi, Jiro Kasahara, Koichi Ishiguro and Kohji Fukunaga : Lithium-induced activation of Akt and CaM kinase II contributes to its neuroprotective action in a rat microsphere embolism model., Brain Research, Vol.1108, No.1, 98-106, 2006.
(要約)
Lithium used in bipolar mood disorder therapy protects neurons from brain ischemic cell death. Here, we documented that lithium administration under microsphere-embolism (ME)-induced brain ischemia restored decreased protein kinase B (Akt) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) activities 24 h after ischemia in rat brain. Akt activation was associated with increased phosphorylation of its potential targets forkhead transcription factor (FKHR) and glycogen synthase kinase-3beta (GSK-3beta). In parallel with decreased CaMKII autophosphorylation, we also found marked dephosphorylation of tau proteins 24-72 h after ME. Increased protein phosphatase 2A (PP2A) activity was found 24 h after ME. Inhibition of increased PP2A activity by lithium treatment apparently mediated restored tau phosphorylation. Taken together, activation of Akt and CaMKII by lithium was associated with neuroprotective activity in ME-induced neuronal injury.
Kohji Fukunaga, Feng Han, Norifumi Shioda, Shigeki Moriguchi, Jiro Kasahara and Yasufumi Shirasaki : DY-9760e, a novel calmodulin inhibitor, exhibits cardioprotective effects in the ischemic heart., Cardiovascular Drug Reviews, Vol.24, No.2, 88-100, 2006.
(要約)
DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride-3.5 hydrate) inhibits Ca(2+)/CaM-dependent nitric oxide synthase (NOS), thereby inhibiting nitric oxide (NO) production. In cardiomyocytes from ischemic rat heart NO and superoxide levels are increased causing protein tyrosine nitration. In hearts subjected to ischemia/reperfusion DY-9760e totally abolishes protein tyrosine nitration. Notably, DY-9760e also inhibits calpain and cas-pase-3 activation that occurs prior to apoptosis in cardiomyocytes. In ischemic hearts fodrin is the substrate for calpain. DY-9760e inhibits fodrin breakdown in the peri-infarct area rather than in the infarct core. In the ischemic rat brain DY-9760e inhibits caspase-3-induced proteolysis of calpastatin, an endogenous calpain inhibitor, suggesting that crosstalk between calpain and caspase-3 is mediated by calpastatin breakdown. Thus, DY-9760e rescues neurons and cardiomyocytes from ischemic injury by inhibiting crosstalk between calpain and caspase-3 as well as protein tyrosine nitration.
Hiroyuki Sakagami, Akifumi Kamata, Hideki Nishimura, Jiro Kasahara, Yuji Owada, Yusuke Takeuchi, Makoto Watanabe, Kohji Fukunaga and Hisatake Kondo : Prominent expression and activity-dependent nuclear translocation of Ca2+/calmodulin-dependent protein kinase Idelta in hippocampal neurons., The European Journal of Neuroscience, Vol.22, No.11, 2697-2707, 2005.
(要約)
Multifunctional Ca2+/calmodulin-dependent protein kinases (CaMKs) including CaMKI, II and IV, are thought to regulate a variety of neuronal functions. Unlike CaMKII, which is regulated by autophosphorylation, CaMKI as well as CaMKIV are activated by CaMKK. In this study, we examined the cellular and subcellular localization of CaMKIdelta, a recently identified fourth isoform of CaMKI, in the mature brain. In situ hybridization analysis demonstrated wide expression of CaMKIdelta mRNA in the adult mouse brain with prominent expression in the hippocampal pyramidal cells. FLAG-tagged CaMKIdelta was localized at the cytoplasm and neurites without nuclear immunoreactivity in approximately 80% of the transfected primary hippocampal neurons. The stimulation with either KCl depolarization or glutamate triggered the nuclear localization of FLAG-tagged CaMKIdelta by two-fold with a peak at 1 min. In contrast, the catalytically inactive mutants of CaMKIdelta remained cytoplasmic without nuclear translocation during KCl depolarization, indicating the requirement of its activation for the nuclear translocation. Furthermore, we showed that immunoprecipitated CaMKIdelta could phosphorylate cAMP response element binding protein (CREB)alphain vitro and that the over-expression of CaMKIdelta enhanced GAL4-CREB-luciferase activity in PC12 cells stimulated by KCl depolarization. Our present study provides the first evidence for the possible involvement of CaMKIdelta in nuclear functions through its nuclear translocation in response to stimuli that trigger intracellular Ca2+ influx.
(キーワード)
Animals / Calcium-Calmodulin-Dependent Protein Kinase Type 1 / Calcium-Calmodulin-Dependent Protein Kinases / Cell Nucleus / Cyclic AMP Response Element-Binding Protein / DNA, Complementary / Female / Genetic Vectors / Glutamic Acid / Hippocampus / In Situ Hybridization / Luciferases / Mice / Mice, Inbred C57BL / Neurons / Phosphorylation / Potassium Chloride / Pregnancy / Protein Transport / Rats / Rats, Wistar / Subcellular Fractions / Transfection
Hiroyuki Nagase, Tohru Yamakuni, Kentaro Matsuzaki, Yuji Maruyama, Jiro Kasahara, Yoshimi Hinohara, Shunzo Kondo, Yoshihiro Mimaki, Yutaka Sashida, William A Tank, Kohji Fukunaga and Yasushi Ohizumi : Mechanism of neurotrophic action of nobiletin in PC12D cells., Biochemistry, Vol.44, No.42, 13683-13691, 2005.
(要約)
Nobiletin is a nonpeptide compound with a low molecular weight from a citrus fruit and has the activity to rescue bulbectomy-induced memory impairment. Here we describe that nobiletin itself induces neurite outgrowth in PC12D cells, a rat pheochromocytoma cell line, like NGF, and the molecular mechanism of its neurotrophic action. As cultured in the presence of nobiletin or NGF for 48 h and then assayed using a scanning electron microscope, PC12D cells treated with nobiletin showed morphology with flatter and larger cell bodies than the cells cultured with NGF. Nobiletin-induced neurite outgrowth was inhibited by PD98059 and U0126 but not K252a. Consistently, nobiletin caused a concentration-dependent enhancement of Erk/MAP kinase phosphorylation and a sustained increment of phosphorylation of MEK and Erk/MAP kinase, resulting in a stimulation of CREB phosphorylation and CRE-mediated transcription. This compound also increased intracellular cAMP and CRE-mediated transcription in the presence of forskolin and enhanced PKA activity to stimulate phosphorylation of multiple PKA substrates in PC12D cells. Furthermore, nobiletin preferentially inhibited Ca2+/CaM-dependent phosphodiesterase in vitro. This compound failed to stimulate phosphorylation of Erk5, which is known to be induced by NGF/TrkA signaling. These results suggest that nobiletin induces neurite outgrowth by activating a cAMP/PKA/MEK/Erk/MAP kinase-dependent but not TrkA-dependent signaling pathway coupling with CRE-mediated gene transcription and may thus become a novel type of biochemical probe for elucidation of the molecular mechanism of neuronal differentiation.
Takashi Shirakura, Feng Han, Norifumi Shiota, Shigeki Moriguchi, Jiro Kasahara, Toshiyuki Sato, Yasufumi Shirasaki and Kohji Fukunaga : Inhibition of nitric oxide production and protein tyrosine nitration contribute to neuroprotection by a novel calmodulin antagonist, DY-9760e, in the rat microsphere embolism., Biological & Pharmaceutical Bulletin, Vol.28, No.9, 1658-1661, 2005.
(要約)
Microsphere embolism (ME)-induced ischemia model in rat resembles to multiple brain embolism in human with several clinical features. We here tested whether nitric oxide (NO) production contributes to the neuronal injury in the ME model. A novel calmodulin antagonist, DY-9760e, having a potent inhibitory effect on neuronal nitric oxide synthase (nNOS), reduced brain infarct size in the ME-induced brain ischemia. Consistent with our previous observation with gerbil ischemia/reperfusion model, DY-9760e completely inhibited NO production immediately after and 24 or 48 h after ME. Unlike the gerbil ischemia/reperfusion model, protein tyrosine nitration markedly increased 6-48 h after ME. DY-9760e treatment completely inhibited the marked increase in the protein tyrosine nitration at 24 h after ME. These results suggest that the inhibition of NO production and protein tyrosine nitration by DY-9760e contribute to its neuroprotective action in the ME-induced brain damage.
Masami Hashimoto, Yoko Takada, Yusuke Takeuchi, Jiro Kasahara, Hiroaki Hisa, Yasufumi Shirasaki and Kohji Fukunaga : Cytoprotective effect of 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e) against ischemia/reperfusion-induced injury in rat heart involves inhibition of fodrin breakdown and protein tyrosine nitration., Journal of Pharmacological Sciences, Vol.98, No.2, 142-150, 2005.
(要約)
We here assessed the effects of 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e), a novel calmodulin antagonist, on infarct size in the rat heart subjected to ischemia/reperfusion. Rats were subjected to a 30-min coronary occlusion followed by a 24-h reperfusion. DY-9760e was intravenously infused for 20 min, starting at 20 min after coronary occlusion. Treatment with DY-9760e (10 mg/kg) significantly reduced the infarct size in the risk area assessed by Evans Blue/TTC (triphenyltetrazolium chloride) staining. DY-9760e treatment also ameliorated contractile dysfunction of the left ventricle 72 h after reperfusion. DY-9760e significantly inhibited fodrin breakdown and caspase-3 activation. The inhibitory effect of DY-9760e on the fodrin breakdown was prominent in the rim rather than in the center of the risk area. DY-9760e also blocked protein tyrosine nitration associated with infarction. These results suggest that the cardioprotective effect of DY-9760e involved inhibition of calpain/caspase activation and protein tyrosine nitration.
Ettore Tiraboschi, Daniela Tardito, Jiro Kasahara, Stefania Moraschi, Paolo Pruneri, Massimo Gennarelli, Giorgio Racagni and Maurizio Popoli : Selective phosphorylation of nuclear CREB by fluoxetine is linked to activation of CaM kinase IV and MAP kinase cascades., Neuropsychopharmacology, Vol.29, No.10, 1831-1840, 2004.
(要約)
Regulation of gene expression is purported as a major component in the long-term action of antidepressants. The transcription factor cAMP-response element-binding protein (CREB) is activated by chronic antidepressant treatments, although a number of studies reported different effects on CREB, depending on drug types used and brain areas investigated. Furthermore, little is known as to what signaling cascades are responsible for CREB activation, although cAMP-protein kinase A (PKA) cascade was suggested to be a central player. We investigated how different drugs (fluoxetine (FLX), desipramine (DMI), reboxetine (RBX)) affect CREB expression and phosphorylation of Ser(133) in the hippocampus and prefrontal/frontal cortex (PFCX). Acute treatments did not induce changes in these mechanisms. Chronic FLX increased nuclear phospho-CREB (pCREB) far more markedly than pronoradrenergic drugs, particularly in PFCX. We investigated the function of the main signaling cascades that were shown to phosphorylate and regulate CREB. PKA did not seem to account for the selective increase of pCREB induced by FLX. All drug treatments markedly increased the enzymatic activity of nuclear Ca2+/calmodulin (CaM) kinase IV (CaMKIV), a major neuronal CREB kinase, in PFCX. Activation of this kinase was due to increased phosphorylation of the activatory residue Thr196, with no major changes in the expression levels of alpha- and beta-CaM kinase kinase, enzymes that phosphorylate CaMKIV. Again in PFCX, FLX selectively increased the expression level of MAP kinases Erk1/2, without affecting their phosphorylation. Our results show that FLX exerts a more marked effect on CREB phosphorylation and suggest that CaMKIV and MAP kinase cascades are involved in this effect.
(キーワード)
Adrenergic Agents / Animals / Antidepressive Agents, Second-Generation / Blotting, Western / Calcium-Calmodulin-Dependent Protein Kinase Type 4 / Calcium-Calmodulin-Dependent Protein Kinases / Cell Nucleus / Cyclic AMP Response Element-Binding Protein / Cyclic AMP-Dependent Protein Kinases / Fluoxetine / Hippocampus / Immunoprecipitation / Male / Mitogen-Activated Protein Kinases / Phosphorylation / Prefrontal Cortex / Rats / Rats, Sprague-Dawley / Reverse Transcriptase Polymerase Chain Reaction / Serotonin Uptake Inhibitors / Signal Transduction
Chiara Cavazzin, Cristian Bonvicini, Annachiara Nocera, Marco Racchi, Jiro Kasahara, Daniela Tardito, Massimo Gennarelli, Stefano Govoni, Giorgio Racagni and Maurizio Popoli : Expression and phosphorylation of delta-CaM kinase II in cultured Alzheimer fibroblasts., Neurobiology of Aging, Vol.25, No.9, 1187-1196, 2004.
(要約)
Dysregulation of calcium homeostasis is among the major cellular alterations in Alzheimer's disease (AD). We studied Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II), one of the major effectors regulating neuronal responses to changes in calcium fluxes, in cultured skin fibroblasts from subjects with sporadic AD. We found, by using PCR and Western analysis, that human fibroblasts express the delta-isoform of this kinase, and that CaM kinase II is the major Ca(2+)/calmodulin-dependent kinase in these cells. Protein expression level of the kinase was not significantly different in AD fibroblasts. However, the total activity of the kinase (stimulated by Ca(2+)/calmodulin) was significantly reduced in AD cell lines, whereas Ca(2+)-independent activity was significantly enhanced. The percent autonomy of the kinase (%Ca(2+)-independent/Ca(2+)-dependent activity) in AD cell lines was 62.8%, three-fold the corresponding percentage in control fibroblasts. The abnormal calcium-independent activity was not due to enhanced basal autophosphorylation of Thr(287). The observed abnormalities, if present in brain tissue, may be implicated either in dysfunction of neuroplasticity and cognitive functions or in dysregulation of cell cycle.
Yoko Takada, Masami Hashimoto, Jiro Kasahara, Kazuyuki Aihara and Kohji Fukunaga : Cytoprotective effect of sodium orthovanadate on ischemia/reperfusion-induced injury in the rat heart involves Akt activation and inhibition of fodrin breakdown and apoptosis., The Journal of Pharmacology and Experimental Therapeutics, Vol.311, No.3, 1249-1255, 2004.
(要約)
In a rat model of myocardial ischemic infarction, sodium orthovanadate rescued cells from ischemia/reperfusion injuries. Rats underwent 30 min of myocardial ischemia by occluding the left coronary artery followed by 24 h of reperfusion. Post-treatment with orthovanadate reduced infarct size in a dose-dependent manner. Orthovanadate treatment also ameliorated contractile dysfunction of the left ventricle 72 h after reperfusion. The cytoprotective action of orthovanadate treatment was closely associated with inhibition of fodrin breakdown. Since orthovanadate is a potent inhibitor for protein tyrosine phosphatases, thereby activating tyrosine kinases and phosphatidylinositol 3-kinase (PI3K) pathways, we investigated activities of protein kinase B (Akt), a downstream target of PI3K in cardiomyocytes. Orthovanadate-induced cytoprotection was associated with partial restoration of reduced Akt activity following myocardial infarction. Restoration of Akt activity by orthovanadate treatment correlated positively with increased phosphorylation of glycogen synthase kinase-3beta and Bad in cardiomyocytes. Furthermore, orthovanadate treatment inhibited caspase-3 activation induced by ischemia. Taken together, orthovanadate post-treatment rescued cardiomyocytes from ischemia/reperfusion injuries via Akt activation and inhibition of fodrin breakdown, thereby inhibiting apoptosis.
Eiko Iwahana, Masashi Akiyama, Kazuko Miyakawa, Ayumi Uchida, Jiro Kasahara, Kohji Fukunaga, Toshiyuki Hamada and Shigenobu Shibata : Effect of lithium on the circadian rhythms of locomotor activity and glycogen synthase kinase-3 protein expression in the mouse suprachiasmatic nuclei., The European Journal of Neuroscience, Vol.19, No.8, 2281-2287, 2004.
(要約)
A circadian clock located in the suprachiasmatic nucleus (SCN) regulates the period of physiological and behavioural rhythms to approximately 24 h. Lithium can lengthen the period of circadian rhythms in most organisms although little is known about the underlying mechanism. In the present study, we examined Drosophila shaggy ortholog glycogen synthase kinase-3 (GSK-3) protein expression in the SCN after lithium treatment. When locomotor activity was assessed, we found an association between the effect of lithium and the period of circadian oscillation as well as the level of GSK-3 protein expression. The decreased expression of GSK-3 and increased expression of phosphorylated GSK-3 (pGSK-3) resulted in an antiphasic circadian rhythm between the two in the SCN of lithium-treated mice housed under both light-dark and constant dark conditions. The enzyme activity of GSK-3 in the SCN was low when the level of pGSK-3 protein was high, as examined by immunoblotting analysis. Thus, GSK-3 enzyme activity has a correlation with the expression of GSK-3 protein in the SCN. Although both GSK-3 and pGSK-3 proteins are also expressed in the arcuate nucleus, lithium did not affect their expression. Based on the association that we found between lengthened circadian period and GSK-3 protein and GSK-3 activity in the SCN, we suggest that GSK-3 plays a role in regulating the period of the mammalian circadian pacemaker.
E Carlos Semino, Jiro Kasahara, Yasunori Hayashi and Shuguang Zhang : Entrapment of migrating hippocampal neural cells in three-dimensional peptide nanofiber scaffold., Tissue Engineering, Vol.10, No.3-4, 643-655, 2004.
(要約)
Isolation and expansion of self-renewing neural cells ex vivo are required for neural tissue repair in regenerative medicine. Neurogenesis occurs in restricted areas of postnatal mammalian brain including dentate gyrus and subventricular zone. We developed a simple method to entrap migrating neural cells (potential neuroprogenitors) from postnatal hippocampal organotypic cultures in three-dimensional (3-D) peptide nanofiber scaffolds. A few hours after placing the hippocampal slices in culture, cell proliferation activity at the "interface zone" between the tissue slice and the membrane culture surface was observed. Pulse-chase experiments using 5-bromodeoxyuridine (BrdU), which measures mitotic activity, showed that a number of cells incorporated BrdU at the interface zone. The number of BrdU(+) cells increased exponentially during the first 3 days of exposure to the label. The BrdU(+) cells also stained positive for glial fibrillary acidic protein (2.2 +/- 0.5%), a marker for astroglia; and for betaIII tubulin (7.3 +/- 2.8%) and nestin (2.7 +/- 0.9%), markers for neural progenitors. When hippocampal slices were cultured on a peptide nanofiber scaffold layer (~500 microm thick), a more extended interface zone between each tissue slice and the scaffold was formed. Moreover, the migrating BrdU(+) cell population entrapped in the 3-D peptide scaffold was readily isolated by mechanically disrupting the scaffold and then used for conventional 2-D culture systems for further studies. This simple method may be useful not only in developing technology for neural progenitor cell isolation and enrichment in vitro, but also for expanding cells for cell-based therapies of regenerative medicine.
Akiyoshi Uezu, Kohji Fukunaga, Jiro Kasahara and Eishichi Miyamoto : Activation of Ca2+/calmodulin-dependent protein kinase I in cultured rat hippocampal neurons., Journal of Neurochemistry, Vol.82, No.3, 585-593, 2002.
(要約)
We have focused on activation mechanisms of calcium/calmodulin-dependent protein kinase (CaM) kinase I in the hippocampal neurons and compared them with that of CaM kinase IV. Increased activation of CaM kinase I occurred by stimulation with glutamate and depolarization in cultured rat hippocampal neurons. Similar to CaM kinases II and IV, CaM kinase I was essentially activated by stimulation with the NMDA receptor. Although both CaM kinases I and IV seem to be activated by CaM kinase kinase, the activation of CaM kinase I was persistent during stimulation with glutamate in contrast to a transient activation of CaM kinase IV. In addition, CaM kinase I was activated in a lower concentration of glutamate than that of CaM kinase IV. Depolarization-induced activation of CaM kinase I was also evident in the cultured neurons and was largely blocked by nifedipine. In the experiment with 32P-labeled cells, phosphorylation of CaM kinase I was stimulated by glutamate treatment and depolarization. The glutamate- and depolarization-induced phosphorylation was inhibited by the NMDA receptor antagonist and nifedipine, respectively. These results suggest that, although CaM kinases I and IV are activated by the NMDA receptor and depolarization stimulation, these kinase activities are differently regulated in the hippocampal neurons.
Jiro Kasahara, K Fukunaga and E Miyamoto : Activation of calcium/calmodulin-dependent protein kinase IV in long term potentiation in the rat hippocampal CA1 region., The Journal of Biological Chemistry, Vol.276, No.26, 24044-24050, 2001.
(要約)
The importance of well characterized calcium/calmodulin-dependent protein kinase (CaMK) II in hippocampal long term potentiation (LTP) is widely well established; however, several CaMKs other than CaMKII are not yet clearly characterized and understood. Here we report the activation of CaMKIV, which is phosphorylated by CaMK kinase and localized predominantly in neuronal nuclei, and its functional role as a cyclic AMP-responsive element-binding protein (CREB) kinase in high frequency stimulation (HFS)-induced LTP in the rat hippocampal CA1 region. CaMKIV was transiently activated in neuronal nuclei after HFS, and the activation returned to the basal level within 30 min. Phosphorylation of CREB, which is a CaMKIV substrate, and expression of c-Fos protein, which is regulated by CREB, increased during LTP. This increase was inhibited mainly by CaMK inhibitors and also by an inhibitor for mitogen-activated protein kinase cascade, although to a lesser extent. Our results suggest that CaMKIV functions as a CREB kinase and controls CREB-regulated gene expression during HFS-induced LTP in the rat hippocampal CA1 region.
(キーワード)
Animals / Calcium-Calmodulin-Dependent Protein Kinase Type 4 / Calcium-Calmodulin-Dependent Protein Kinases / Calmodulin / Culture Techniques / Cyclic AMP Response Element-Binding Protein / Cyclic AMP-Dependent Protein Kinases / Electric Stimulation / Enzyme Activation / Enzyme Inhibitors / Hippocampus / Long-Term Potentiation / MAP Kinase Kinase 1 / Male / Mitogen-Activated Protein Kinase 1 / Mitogen-Activated Protein Kinase Kinases / Phosphorylation / Protein-Serine-Threonine Kinases / Proto-Oncogene Proteins c-fos / Rats / Rats, Wistar
Jiro Kasahara, K Fukunaga and E Miyamoto : Activation of CA(2+)/calmodulin-dependent protein kinase IV in cultured rat hippocampal neurons., Journal of Neuroscience Research, Vol.59, No.5, 594-600, 2000.
(要約)
Ca(2+)/calmodulin-dependent protein kinase IV (CaM kinase IV) is a multifunctional enzyme that is abundantly present in the nuclei of neurons. We report the properties of phosphorylation and activation of CaM kinase IV in comparison to CaM kinase II in cultured rat hippocampal neurons. Phosphorylation and activity of CaM kinase IV as well as CaM kinase II were increased by treatment of neurons either with glutamate or high K(+). Glutamate-induced phosphorylation and activity of CaM kinase IV were blocked by N-methyl-D-asparate (NMDA) antagonists, and NMDA application instead of glutamate did increase CaM kinase IV phosphorylation. CaM kinase IV phosphorylation was also increased by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA), and was blocked by an inhibitor of NMDA receptor. The AMPA-induced phosphorylation was blocked by tetrodotoxin, a Na(+) channel blocker, that was expected to block endogenous glutamate transmission indirectly. On the other hand, high K(+)-induced phosphorylation and activation were not blocked by inhibitors of glutamate receptors, and effectively blocked by nifedipine, an L-type Ca(2+) channel blocker. These properties were similar between CaM kinase IV and CaM kinase II.
(キーワード)
Animals / Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Calcium-Calmodulin-Dependent Protein Kinase Type 4 / Calcium-Calmodulin-Dependent Protein Kinases / Cells, Cultured / Enzyme Activation / Excitatory Amino Acid Agonists / Glutamic Acid / Hippocampus / Neurons / Phosphorylation / Potassium / Rats / Rats, Wistar
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 10686587
T Osaki, M Omotezako, R Nagayama, M Hirata, S Iwanaga, Jiro Kasahara, J Hattori, I Ito, H Sugiyama and S Kawabata : Horseshoe crab hemocyte-derived antimicrobial polypeptides, tachystatins, with sequence similarity to spider neurotoxins., The Journal of Biological Chemistry, Vol.274, No.37, 26172-26178, 1999.
(要約)
Antimicrobial peptides, named tachystatins A, B, and C, were identified from hemocytes of the horseshoe crab Tachypleus tridentatus. Tachystatins exhibited a broad spectrum of antimicrobial activity against Gram-negative and Gram-positive bacteria and fungi. Of these tachystatins, tachystatin C was most effective. Tachystatin A is homologous to tachystatin B, but tachystatin C has no significant sequence similarity to tachystatins A and B. Tachystatins A and B showed sequence similarity to omega-agatoxin-IVA of funnel web spider venom, a potent blocker of voltage-dependent calcium channels. However, they exhibited no blocking activity of the P-type calcium channel in rat Purkinje cells. Tachystatin C also showed sequence similarity to several insecticidal neurotoxins of spider venoms. Tachystatins A, B, and C bound significantly to chitin. A causal relationship was observed between chitin binding activity and antifungal activity. Tachystatins caused morphological changes against a budding yeast, and tachystatin C had a strong cell lysis activity. The septum between mother cell and bud, a chitin-rich region, was stained by fluorescence-labeled tachystatin C, suggesting that the primary recognizing substance on the cell wall is chitin. As horseshoe crab is a close relative of the spider, tachystatins and spider neurotoxins may have evolved from a common ancestral peptide, with adaptive functions.
Jiro Kasahara, K Fukunaga and E Miyamoto : Differential effects of a calcineurin inhibitor on glutamate-induced phosphorylation of Ca2+/calmodulin-dependent protein kinases in cultured rat hippocampal neurons., The Journal of Biological Chemistry, Vol.274, No.13, 9061-9067, 1999.
(要約)
Calcium/calmodulin-dependent protein kinases (CaM kinases) are major multifunctional enzymes that play important roles in calcium-mediated signal transduction. To characterize their regulatory mechanisms in neurons, we compared glutamate-induced phosphorylation of CaM kinase IV and CaM kinase II in cultured rat hippocampal neurons. We observed that dephosphorylation of these kinases followed different time courses, suggesting different regulatory mechanisms for each kinase. Okadaic acid, an inhibitor of protein phosphatase (PP) 1 and PP2A, increased the phosphorylation of both kinases. In contrast, cyclosporin A, an inhibitor of calcineurin, showed different effects: the phosphorylation and activity of CaM kinase IV were significantly increased with this inhibitor, but those of CaM kinase II were not significantly increased. Cyclosporin A treatment of neurons increased phosphorylation of Thr196 of CaM kinase IV, the activated form with CaM kinase kinase, which was recognized with an anti-phospho-Thr196 antibody. Moreover, recombinant CaM kinase IV was dephosphorylated and inactivated with calcineurin as well as with PP1, PP2A, and PP2C in vitro. These results suggest that CaM kinase IV, but not CaM kinase II, is directly regulated with calcineurin.
(キーワード)
Animals / Calcineurin / Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Calcium-Calmodulin-Dependent Protein Kinase Type 4 / Calcium-Calmodulin-Dependent Protein Kinases / Cells, Cultured / Cyclosporine / Enzyme Inhibitors / Glutamic Acid / Hippocampus / Neurons / Okadaic Acid / Phosphoprotein Phosphatases / Phosphorylation / Rats / Recombinant Proteins
(文献検索サイトへのリンク)
● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 10085155
Jiro Kasahara and H Sugiyama : Modulation of glutamate sensitivities by inhibitors of a protein kinase and a protein phosphatase in cultured rat Purkinje cells., Neuroscience Letters, Vol.247, No.2-3, 139-142, 1998.
(要約)
We examined the effects of inhibitors of calcium-calmodulin-dependent protein kinase II (CaM kinase II) and protein phosphatases on the glutamate (Glu) responses in cultured rat cerebellar Purkinje cells. CaM kinase II inhibitors significantly potentiated Glu responses, and activation of metabotropic Glu receptors facilitated this potentiation. In contrast, a phosphatase inhibitor calyculin A significantly reduced Glu responses. It was suggested that the Glu responsiveness of Purkinje cells may be regulated by the dynamic balance of phosphorylation and dephosphorylation of receptors or other relevant factors under basal conditions.
K Fujii, Jiro Kasahara, K Nakamura and H Sugiyama : Differential selectivity of M1 and M3 type muscarinic acetylcholine receptors in coupling with a G protein G01 alpha examined in Xenopus oocytes., Neuroscience Letters, Vol.215, No.2, 131-133, 1996.
(要約)
The coupling specificities between muscarinic acetylcholine receptors (porcine M1 and M3 subtypes) and a heterotrimeric GTP binding protein (bovine G01) were examined by analysing receptor-stimulated, phospholipase C (PLC)-mediated chloride current responses in Xenopus oocyte expression system. M1-stimulated responses were suppressed by G01 alpha, and this suppression was reversed by expressing exogenous G beta and G gamma, whereas M3-stimulated responses were enhanced by G01 alpha in the presence or absence of G beta and G gamma. G01 alpha itself, when activated directly by intracellular fluoride injection, efficiently activated PLC and stimulated chloride current responses. The results indicate that M1 receptor does not couple with G01, while M3 receptor activates G01 effectively.
(キーワード)
Animals / Cattle / Electrophysiology / Female / GTP-Binding Protein alpha Subunits, Gi-Go / GTP-Binding Proteins / Microinjections / Oocytes / Peptides / RNA, Messenger / Receptors, Muscarinic / Sensitivity and Specificity / Swine / Type C Phospholipases / Xenopus
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● PubMed @ National Institutes of Health, US National Library of Medicine (PMID): 8888013
Jiro Kasahara and H Sugiyama : Inositol phospholipid metabolism in Xenopus oocytes mediated by endogenous G(o) and Gi proteins., FEBS Letters, Vol.355, No.1, 41-44, 1994.
(要約)
To characterize G-proteins which mediate the signal transduction from ligand stimulated receptor to phospholipase C (PLC), we injected antisense DNAs complementary to Xenopus G(o) alpha or Gi-l alpha to suppress these endogenous G-proteins, together with the mRNAs encoding metabotropic glutamate receptor 1 (mGluR1), 5 (mGluR5) or with M1 type muscarinic receptor into oocytes. Receptor-stimulated chloride current responses were reduced by the suppression of Xenopus G(o) alpha regardless of the types of receptors. However, injection of Gi-1 antisense DNA resulted in the reduction of M1-stimulated responses but not mGluR-stimulated responses. These results suggested that all these receptors could use G(o) alpha, and M1 receptors, but not mGluRs, could also use Gi-1 proteins, to activate PLC in Xenopus oocytes.
Calcium signaling plays a critical role in various cell types by activation of receptors and Ca2+ channels in response to neurotransmitters, hormones, growth, factors etc. Although a variety of functions of intracellular Ca2+ are reported, Ca2+/calmodulin-dependent protein kinases (CaMK) are involved in their mediation. We have been studying on CaMK I, II, III, IV and K in the dynamic regulation in the cells in relation to functions. In this study, we elucidated the structures of the isoforms of CaMKII subunits with nuclear translocation signal (NTS). NTS is included in the variable domain following the regulatory domain with a sequence of KKRK. The isoforms of CaMK subunits such as alpha B, gamma A, gamma A.B, delta 3 and delta 7 contain NTS in the sequences of the structures. Transfection of the isoforms with NTS into NG108-15 cells stimulated the expression of brain-derived neurotrophic factor in the cytoplasm. Activation of CaMKII and IV and mitogen-activated protein kinase (MAPK) was observed during long-term potentiation (LTP) induction in the CA1 area of hippocampus. The activation of CaMKII was sustained for a long period, whereas that of CaMKIV and MAPK was transient. The results suggest that CaMKII is involved in LTP induction, while CaMKIV and MAPK are rather involved in LTP maintenance. We present and discuss our recent studies on regulation of CaMKs in neuronal functions.
Yuka Torii, Sohei Tsugita, Yukuto Ogawa, Hiten Iwamoto, Jiro Kasahara, Masaki Takeuchi, Masamitsu Iiyama, Toshio Takayanagi and Hitoshi Mizuguchi : Dopamine monitoring in a mouse brain using a microdialysis-integrated HPLC equipped with a track-etched membrane double-electrode detector, 10th International Conference on Advanced Materials Development and Performance (AMDP2024), Tokushima, Sep. 2024.
2.
Hitoshi Mizuguchi, Yuka Torii, Sohei Tsugita, Yukuto Ogawa, Hiten Iwamoto, Masaki Takeuchi, Masamitsu Iiyama, Toshio Takayanagi and Jiro Kasahara : A Microdialysis-Integrated HPLC System Constructed Using Track-Etched Membrane Electrodes for Dopamine Monitoring in Mouse Brain, 19th Asia-Pacific International Symposium on Microscale Separations and Analysis 2023 (APCE 2023), Kuala Lumpur, Oct. 2023.
3.
Yuka Torii, Sohei Tsugita, Yukuto Ogawa, Hiten Iwamoto, Jiro Kasahara, Masaki Takeuchi, Masamitsu Iiyama, Toshio Takayanagi and Hitoshi Mizuguchi : Dopamine monitoring in a mouse brain using a microdialysis-integrated HPLC equipped with a track-etched membrane double-electrode detector, Royal Society of Chemistry Tokyo International Conference 2023 (RSC-TIC 2023), Chiba, Sep. 2023.
4.
Ryoma Morigaki, Maya Anzai, Joji Fujikawa, Teruo Oda, Hayasawa Hiroaki, Matsuda Taku, Jiro Kasahara and Yasushi Takagi : Changes in phosphodiesterase 10A in mice model of levodopa-induced dyskinesia, The 13th Scientific meeting of Asian Australasian Society for Stereotactic and Functional Neurosurgery (AASSFN 2023), Osaka, Apr. 2023.
5.
Jiro Kasahara, 政宗 宏子, 多田羅 瑞樹 and 村上 夏子 : Imipramine ameliorates cognitive dysfunction with facilitatiing differentiation of the hippocampal CA1 neurons in a rat model of cerebral ischemia., Neuro2019, Niigata, Jul. 2019.
6.
Jiro Kasahara : Post-ischemic depression and the hippocampal neurodegeneration, WCP2018, Kyoto, Jul. 2018.
Jiro Kasahara : KAMIKATSU, a tiny rural village with plentiful resources for health and wellness in Tokushima, Japan, Botanicals for Nutrition and Health: from Nagoya protocol to the international cooperation, Jul. 2015.
9.
Jiro Kasahara, Yamamura Yukio, Tanabe Akie, Ryoma Morigaki, Ryuji Kaji and Satoshi Goto : Inhibition of c-Abelson tyrosine kinase (c-Abl) as a possible strategy for treatment of PD: Study in MPTP-induced mice model, The 12th International Conference on Alzheimers's and Parkinson;s Disease: AD/PD 2015, Mar. 2015.
10.
Jiro Kasahara : Neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model for Parkinson's disease, 6th International Conference on Drug Discovery & Therapy, Dubai, UAE, Feb. 2014.
11.
Jiro Kasahara, Adachi Minami, Ohmura Koji, Fukunaga Kohji and Tsutomu Araki : Serotonin (5-HT)-induced CREB phosphorylation in the cortical neurons of mice, Soc. Abst. Neurosci., Vol.40, 741-18, Nov. 2010.
12.
Jiro Kasahara, Kohji Fukunaga and Hiroyuki Sakagami : Requirement of calcium/calmodulin-dependent protein kinase IV (CaMKIV)-activity for the effects of antidepressants in mouse brain., Soc.Neurosci.Abst., Vol.37, 807.7, Nov. 2007.
13.
Jiro Kasahara, Kohji Fukunaga and Hiroyuki Sakagami : Calcium/calmodulin-dependent protein kinase IV is important to regulate depression-related behaviors and sensitivity to antidepressants, Soc.Neurosci.Abst., Vol.36, 768.18, Oct. 2006.
14.
Jiro Kasahara and Kohji Fukunaga : CaMKK activities in the hippocampal neurons, Soc.Neurosci.Abst., Vol.34, 298.11, Nov. 2004.
15.
Jiro Kasahara, Akiyoshi Uezu, Kohji Fukunaga and Eishichi Miyamoto : Subtype specific profiles of phosphorylation and activation of calcium/calmodulin-dependent protein kinases in rat hippocampal neurons., XII International Symposium on Calcium-Binding Proteins and Calcium Function in Healh and Disease, Vol.12, 79, Feb. 2002.
16.
Jiro Kasahara, Kohji Fukunaga and Eishichi Miyamoto : Characterization of CaM kinase IV in rat hippocampal neurons and LTP., Soc.Neurosci.Abst., Vol.30, 262.2, Nov. 2000.
17.
Jiro Kasahara, Akiyoshi Uezu, Kohji Fukunaga and Eishichi Miyamoto : CaM kinases in hippocampal neurons: localization and phosphorylation., International Symposium on Neuronal Signaling and Protein Phosphorylation-Dephosphorylation, May 2000.
18.
Jiro Kasahara, Kohji Fukunaga and Eishichi Miyamoto : Acication and regulation of CaM kinase IV in neurons., International Symposium on Calcium-Binding Proteins and Calcium Function in Healh and Disease, Vol.11, IV-6, Oct. 1999.
Jiro Kasahara, 小川 允利, 周 禹, 辻 諒佑 and 後藤 惠 : Intrastriatal infusion of memantine with a programmable pump in a mouse model of hemi-parkinsonism, 第43回 日本神経科学大会, Jul. 2020.
<p>Parkinson's disease is a neurodegenerative disorder cased by loss of nigrostriatal dopaminergic neurons. For over 40 years, levodopa had been established as a gold standard for PD treatment. However, long-term treatment with levodopa is often complicated by the development of adverse effects such as abnormal involuntary movements (AIMs), referred to as levodopa-induced dyskinesia (LIDs). We here report the pharmacological effects of the intrastriatal infusion of memantine, a non-competitive <i>N</i>-methyl-D-aspartate (NMDA) receptor antagonist, in a 6-OHDA-lesioned mouse model of hemiparkinsonism. Spontaneous and apomorphine-induced rotational activities with an abnormal hind limb stepping were assessed as Parkinsonian symptoms. Daily intraperitoneal injection of levodopa (15 mg/kg) was performed for 21 days, with assessing AIMs score as an index of LID development. Intrastriatal memantine infusion targeted into the right dorsal striatum, using an iPRECIO<sup>TM</sup> programmable micro infusion pump with a brain infusion kit, was examined with 4 doses (3 days/dose). Infusion of memantine significantly alleviated Parkinsonian symptoms, and it also reduced AIMs score with a dose-dependent manner. These results support the idea that over-activation of the striatal NMDA receptor function might generate both Parkinsonian symptoms and LIDs.</p>
田邉 彬恵, 山村 行生, Jiro Kasahara, 森垣 龍馬, 梶 龍兒, 永廣 信治 and 後藤 惠 : A novel target for PD therapeutics: A c-Abl inhibitor improved striatal motor dysfunction in MPTP mice, 第87回日本薬理学会年会, Mar. 2014.
Jiro Kasahara, Hiroyuki Sakagami and Kohji Fukunaga : CaMKIV is important to regulate the sensitivity to antidepressants., 神経化学, Vol.45, No.2,3, IS2-6, Sep. 2006.
Jiro Kasahara, Kohji Fukunaga and Hiroyuki Sakagami : Assessments of depression and the sensitivity to antidepressants in calcium/calmodulin-dependent protein kinase IV-knockout mice, Japan. J. Physiol., Vol.3S, 42H2, Mar. 2006.
Jiro Kasahara, Akiyoshi Uezu and Kohji Fukunaga : The regulatory mechanisms of CaM kinases I and IV in the hippocampal neurons, 神経化学, Vol.42, No.2,3, N148-MS6-3, Sep. 2003.