45 results on '"Yasufumi Shirasaki"'
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2. The Post-ischemic Administration 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, Prevents Delayed Neuronal Death in Gerbil Hippocampus
- Author
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Akihito Hashiguchi, Shigetoshi Yano, Motohiro Morioka, Junichiro Hamada, Yasufumi Shirasaki, Masato Kochi, and Kohji Fukunaga
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Therapeutics. Pharmacology ,RM1-950 - Abstract
The novel calmodulin (CaM) antagonist DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate) with an apparent neuroprotective effect in vivo preferentially inhibits neuronal nitric oxide synthase (nNOS), Ca2+/CaM-dependent protein kinase IIα (CaMKIIα), and calcineurin in vitro. In the present study, we investigated the molecular mechanism underlying its neuroprotective effect with the gerbil transient forebrain ischemia model, by focusing on its inhibition of these Ca2+/CaM-dependent enzymes. Post-ischemic DY-9760e treatment (5 mg/kg, i.p.) immediately after 5-min ischemia significantly reduced the delayed neuronal death in the hippocampal CA1 region. CaMKIIα was transiently autophosphorylated immediately after reperfusion with concomitant sustained decrease in its total amounts in the Triton X-100-soluble fractions. Calcineurin activity, accessed by the phosphorylation state of dopamine- and cAMP-regulated phosphoprotein of Mr 32,000 (DARPP-32) at Thr34, was elevated at 6 h after reperfusion. Post-treatment of DY-9760e had no effects on both CaMKIIα and DARPP-32 phosphorylation at 6 h after reperfusion. However, DY-9760e significantly inhibited nitrotyrosine formation, as a biomarker of NO, and in turn, peroxynitrite (ONOO-) production. These results suggest that DY-9760e primarily inhibits Ca2+/CaM-dependent neuronal NOS, without any effects on CaMKII and calcineurin, and the inhibition of NO production possibly accounts for its neuroprotective action in brain ischemic injury. Keywords:: cerebral ischemia, nitric oxide synthase (NOS), Ca2+/calmodulin-dependent protein kinase II (CaMKII), calcineurin, dopamine- and cAMP-regulated phosphoprotein of Mr 32,000 (DARPP-32)
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- 2004
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3. CaMKIIδB mediates aberrant NCX1 expression and the imbalance of NCX1/SERCA in transverse aortic constriction-induced failing heart.
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Ying-Mei Lu, Jiyun Huang, Norifumi Shioda, Kohji Fukunaga, Yasufumi Shirasaki, Xiao-Ming Li, and Feng Han
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Medicine ,Science - Abstract
Ca²⁺/calmodulin-dependent protein kinase II δB (CaMKIIδB) is one of the predominant isoforms of CaMKII in the heart. The precise role of CaMKIIδB in the transcriptional cross-talk of Ca²⁺-handling proteins during heart failure remains unclear. In this work, we aim to determine the mechanism of CaMKIIδB in modulating the expression of sarcolemmal Na⁺-Ca²⁺ exchange (NCX1). We also aim to address the potential effects of calmodulin antagonism on the imbalance of NCX1 and sarcoendoplasmic reticulum Ca²⁺ ATPase (SERCA) during heart failure. Eight weeks after transverse aortic constriction (TAC)-induced heart failure in mice, we found that the heart weight/tibia length (HW/TL) ratio and the lung weight/body weight (LW/BW) ratio increased by 59% and 133%, respectively. We further found that the left ventricle-shortening fraction decreased by 40% compared with the sham-operated controls. Immunoblotting revealed that the phosphorylation of CaMKIIδB significantly increased 8 weeks after TAC-induced heart failure. NCX1 protein levels were also elevated, whereas SERCA2 protein levels decreased in the same animal model. Moreover, transfection of active CaMKIIδB significantly increased NCX1 protein levels in adult mouse cardiomyocytes via class IIa histone deacetylase (HDAC)/myocyte enhancer factor-2 (MEF2)-dependent signaling. In addition, pharmacological inhibition of calmodulin/CaMKIIδB activity improved cardiac function in TAC mice, which partially normalized the imbalance between NCX1 and SERCA2. These data identify NCX1 as a cellular target for CaMKIIδB. We also suggest that the CaMKIIδB-induced imbalance between NCX1 and SERCA2 is partially responsible for the disturbance of intracellular Ca²⁺ homeostasis and the pathological process of heart failure.
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- 2011
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4. A study of the properties of chlorine dioxide gas as a fumigant
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Toshiaki Hayashi, Masashi Uekusa, Yoshihiro Ito, Ayumi Matsuura, and Yasufumi Shirasaki
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0301 basic medicine ,Staphylococcus aureus ,Original ,030106 microbiology ,Sodium chlorite ,Fumigation ,Mixing (process engineering) ,Bacillus ,General Biochemistry, Genetics and Molecular Biology ,fumigant ,Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,Chlorides ,Escherichia coli ,chlorine dioxide gas ,Animals ,Relative humidity ,Phosphoric Acids ,bacteria ,Phosphoric acid ,Chlorine dioxide ,General Veterinary ,biology ,Dose-Response Relationship, Drug ,Humidity ,Oxides ,biological indicator ,General Medicine ,biology.organism_classification ,Housing, Animal ,animal facilities ,Disinfection ,Solutions ,Bacillus atrophaeus ,chemistry ,Animal Science and Zoology ,Gases ,Chlorine Compounds ,Nuclear chemistry - Abstract
Chlorine dioxide (ClO2) is a strong oxidant that possesses an antimicrobial activity. We demonstrated here that ClO2 gas is easily generated by mixing 3.35% sodium chlorite solution (Purogene) and 85% phosphoric acid at a 10:1 volume ratio without using an expensive machine. In a test room (87 m(3)), experiments were carried out using various amounts of sodium chlorite solution (0.25 ml/m(3) to 20.0 ml/m(3)). The gas concentration increased in a sodium chlorite volume-dependent manner and reached peak values of from 0.8 ppm to 40.8 ppm at 2 h-3 h, and then gradually decreased. No differences in gas concentrations were observed between 0.1 and 2.5 m above the floor, indicating that the gas was evenly distributed. Under high-humidity (approximately 80% relative humidity), colony formation of both Staphylococcus aureus and Escherichia coli was completely inhibited by ClO2 gas exposure at 1.0 ml/m(3) sodium chlorite solution (mean maximal concentration of 3.0 ppm). Exposure at 4.0 ml/m(3) sodium chlorite solution (mean maximal concentration of 10.6 ppm) achieved complete inactivation of Bacillus atrophaeus spores. In contrast, without humidification, the efficacy of ClO2 gas was apparently attenuated, suggesting that the atmospheric moisture is indispensable. Delicate electronic devices (computer, camera, etc.) operated normally, even after being subjected to more than 20 times of fumigation. Considering that our method for gas generation is simple, reproducible, and highly effective at decontaminating microbes, our approach is expected to serve as an inexpensive alternative method for cleaning and disinfecting animal facilities.
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- 2016
5. Bromocriptine, an ergot alkaloid, inhibits excitatory amino acid release mediated by glutamate transporter reversal
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Toshiyuki Sato, Yasufumi Shirasaki, and Masunobu Sugimura
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Agonist ,medicine.medical_specialty ,medicine.drug_class ,Excitatory Amino Acids ,Blotting, Western ,Glutamic Acid ,Transfection ,Dopamine agonist ,Cell Line ,Mice ,chemistry.chemical_compound ,Dopamine ,Internal medicine ,medicine ,Glutamate aspartate transporter ,Animals ,Humans ,Neurotransmitter ,Bromocriptine ,Pharmacology ,Dose-Response Relationship, Drug ,biology ,Glutamate receptor ,Glutamic acid ,Endocrinology ,Excitatory Amino Acid Transporter 2 ,chemistry ,Astrocytes ,Dopamine Agonists ,biology.protein ,Excitatory Amino Acid Antagonists ,medicine.drug - Abstract
Bromocriptine, a dopamine D(2) receptor agonist, has widely been used for patients with Parkinson's disease. The aim of the present study was to investigate the effect of bromocriptine on glutamate transporter. Since the astroglial glutamate transporter GLT-1 (EAAT2) is the predominant isoform in the forebrain, we generated EAAT2-expressing human embryonic kidney cells and immortalized mouse astrocytes. In the present studies, we observed a GLT-1-immunoreactive band and significant Na(+)-dependent d-[(3)H] aspartate uptake. Furthermore, the glutamate transporter inhibitors, dl-threo-beta-benzyloxyaspartic acid (TBOA) and dihydrokainate (DHK), displayed a dose-dependent reduction of d-[(3)H] aspartate uptake in both types of cells. In contrast, cells exposed to either chemical anoxia or high KCl elicited a marked release of d-[(3)H] aspartate, and the release was inhibited by TBOA and DHK, implying the contribution of glutamate transporter reversal. Interestingly, we found that bromocriptine dose-dependently inhibits d-[(3)H] aspartate release elicited by chemical anoxia or high KCl, while no changes occurred in the uptake. The inhibitory action of bromocriptine was not affected by sulpiride, a dopamine D(2) receptor antagonist. On the other hand, bromocriptine had no effect on swelling-induced d-[(3)H] aspartate release, which is mediated by volume-regulated anion channels. In vivo studies revealed that bromocriptine suppresses the excessive elevation of glutamate levels in gerbils subjected to transient forebrain ischemia in a manner similar to DHK. Taken together, these results provide evidence that bromocriptine inhibits excitatory amino acid release via reversed operation of GLT-1 without altering forward transport.
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- 2010
6. Phenylephrine-Induced Cardiomyocyte Injury Is Triggered by Superoxide Generation through Uncoupled Endothelial Nitric-Oxide Synthase and Ameliorated by 3-[2-[4-(3-Chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxyindazole (DY-9836), a Novel Calmodulin Antagonist
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Kohji Fukunaga, Shigeki Moriguchi, Norifumi Shioda, Ying Mei Lu, Yasufumi Shirasaki, Feng Han, and Zheng-Hong Qin
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Cardiotonic Agents ,Indazoles ,Time Factors ,Nitric Oxide Synthase Type III ,Caveolin 3 ,Phalloidine ,Heart Ventricles ,Pharmacology ,Nitric Oxide ,Piperazines ,Nitric oxide ,Dystrophin ,Phenylephrine ,chemistry.chemical_compound ,Calmodulin ,Superoxides ,Enos ,medicine ,Animals ,Myocyte ,Myocytes, Cardiac ,Rats, Wistar ,Fluorescent Antibody Technique, Indirect ,Cells, Cultured ,Fluorescent Dyes ,biology ,Rhodamines ,Superoxide ,Antagonist ,biology.organism_classification ,Immunohistochemistry ,Rats ,Animals, Newborn ,chemistry ,Apoptosis ,Molecular Medicine ,medicine.drug - Abstract
The pathophysiological relevance of endothelial nitric-oxide synthase (eNOS)-induced superoxide production in cardiomyocyte injury after prolonged phenylephrine (PE) exposure remains unclear. The aims of this study were to define the mechanism of O2(*) production by uncoupled eNOS and evaluate the therapeutic potential of a novel calmodulin antagonist 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxyindazole (DY-9836) to rescue hypertrophied cardiomyocytes from PE-induced injury. In cultured rat cardiomyocytes, prolonged exposure for 96 h to PE led to translocation from membrane to cytosol of eNOS and breakdown of caveolin-3 and dystrophin. When NO and O2(*) production were monitored in PE-treated cells by 4-amino-5-methylamino-2',7'-difluorofluorescein and dihydroethidium, respectively, Ca(2+)-induced NO production elevated by 5.7-fold (p < 0.01) after 48-h PE treatment, and the basal NO concentration markedly elevated (16-fold; p < 0.01) after 96-h PE treatment. On the other hand, the O2(*) generation at 96 h was closely associated with an increased uncoupled eNOS level. Coincubation with DY-9836 (3 microM) during the last 48 h inhibited the aberrant O2(*) generation nearly completely and NO production by 72% (p < 0.01) after 96 h of PE treatment and inhibited the breakdown of caveolin-3/dystrophin in cardiomyocytes. PE-induced apoptosis assessed by TdT-mediated dUTP nick-end labeling staining was also attenuated by DY-9836 treatment. These results suggest that O2(*) generation by uncoupled eNOS probably triggers PE-induced cardiomyocyte injury. Inhibition of abnormal O2(*) and NO generation by DY-9836 treatment represents an attractive therapeutic strategy for PE/hypertrophy-induced cardiomyocyte injury.
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- 2008
7. Involvement of calmodulin in neuronal cell death
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Mitsuhiro Makino, Yoshito Kanazawa, Yoshiyuki Morishima, and Yasufumi Shirasaki
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Programmed cell death ,Calmodulin ,Neurotoxins ,Excitotoxicity ,Glutamic Acid ,Transfection ,medicine.disease_cause ,Brain Ischemia ,Membrane Potentials ,Potassium Chloride ,medicine ,Animals ,Humans ,Calcium Signaling ,Rats, Wistar ,Molecular Biology ,Cells, Cultured ,Binding Sites ,Cell Death ,biology ,General Neuroscience ,Neurotoxicity ,Brain ,Depolarization ,Cerebral Infarction ,medicine.disease ,Rats ,medicine.anatomical_structure ,Cytoprotection ,Mutation ,Nerve Degeneration ,biology.protein ,Calcium ,Neurology (clinical) ,Neuron ,Signal transduction ,Neuroscience ,Intracellular ,Developmental Biology - Abstract
A large body of evidence indicates that disturbances of Ca(2+) homeostasis may be a causative factor in the neurotoxicity following cerebral ischemia. However, the mechanisms by which Ca(2+) overload leads to neuronal cell death have not been fully elucidated. Calmodulin, a major intracellular Ca(2+)-binding protein found mainly in the central nervous system, mediates many physiological functions in response to changes in the intracellular Ca(2+) concentration, whereas Ca(2+) overload in neurons after excitotoxic insult may induce excessive activation of calmodulin signaling pathways, leading to neuronal cell death. To determine the role of calmodulin in the induction of neuronal cell death, we generated primary rat cortical neurons that express a mutant calmodulin with a defect in Ca(2+)-binding affinity. Neurons expressing the mutant had low responses of calmodulin-dependent signaling to membrane depolarization by high KCl and became resistant to glutamate-triggered excitotoxic neuronal cell death compared with the vector or wild-type calmodulin-transfected cells, indicating that blocking calmodulin function is protective against excitotoxic insult. These results suggest that calmodulin plays a crucial role in the processes of Ca(2+)-induced neuronal cell death and the possibility that the blockage of calmodulin attenuates brain injury after cerebral ischemia.
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- 2006
8. 3-[2-[4-(3-Chloro-2-methylphenylmethyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole Dihydro-chloride 3.5 Hydrate (DY-9760e) Is Neuroprotective in Rat Microsphere Embolism: Role of the Cross-Talk between Calpain and Caspase-3 through Calpastatin
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Feng Han, Kohji Fukunaga, and Yasufumi Shirasaki
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Pharmacology ,biology ,Calmodulin ,Chemistry ,Antagonist ,Calpain ,Caspase 3 ,Neuroprotection ,Enzyme activator ,Biochemistry ,biology.protein ,Molecular Medicine ,Caspase ,Calpastatin - Abstract
Microsphere embolism (ME)-induced cerebral ischemia can elicit various pathological events leading to neuronal death. Western blotting and immunohistochemical studies revealed that expression of calpastatin, an endogenous calpain inhibitor, decreased after ME induction. Calpain activation after ME was apparently due to, in part, a decrease in calpastatin in a late phase of neuronal injury. The time course of that decrease also paralleled caspase-3 activation. In vitro studies demonstrated that calpastatin was degraded by caspase-3 in a Ca(2+)/calmodulin (CaM)-dependent manner. Because CaM binds directly to calpastatin, we asked whether a novel CaM antagonist, 3-[2-[4-(3-chloro-2-methylphenylmethyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydro-chloride 3.5 hydrate (DY-9760e), inhibits caspase-3-induced calpastatin degradation during ME-induced neuronal damage. We also tested the effect of DY-9760e on degradation of fodrin, a calpain substrate. Consistent with our hypothesis, DY-9760e (25 or 50 mg/kg i.p.) treatment inhibited degradation of calpastatin and fodrin in a dose-dependent manner. Because DY-9760e showed powerful neuroprotective activity with concomitant inhibition of calpastatin degradation, cross-talk between calpain and caspase-3 through calpastatin possibly accounts for ME-induced neuronal injury. Taken together, both inhibition of caspase-3-induced calpastatin degradation and calpain-induced fodrin breakdown by DY-9760e in part mediate its neuroprotective action.
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- 2006
9. Serum S-100b protein as a biomarker for the assessment of neuroprotectants
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Yasufumi Shirasaki, Naoko Edo, and Toshiyuki Sato
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Male ,Pathology ,medicine.medical_specialty ,medicine.drug_class ,Ischemia ,Brain Edema ,Enzyme-Linked Immunosorbent Assay ,S100 Calcium Binding Protein beta Subunit ,Brain damage ,Pharmacology ,Neuroprotection ,Brain Ischemia ,Cerebral edema ,medicine ,Animals ,Nerve Growth Factors ,Molecular Biology ,Stroke ,business.industry ,General Neuroscience ,S100 Proteins ,Antagonist ,medicine.disease ,Receptor antagonist ,Microspheres ,Rats ,Disease Models, Animal ,Neuroprotective Agents ,Intracranial Embolism ,NMDA receptor ,Neurology (clinical) ,medicine.symptom ,business ,Biomarkers ,Developmental Biology - Abstract
The study of biomarkers associated with stroke has proved to be of considerable utility. The astroglial protein S-100b is a candidate marker for cerebral tissue damage. We used a rat embolic model produced by injection of microspheres to demonstrate that serum S-100b is a useful biochemical marker for ischemic brain injury. Serum S-100b levels were significantly increased following microsphere injection, which was closely correlated with the development of brain edema. We found that structurally and mechanistically independent neuroprotective agents, such as 3-[2-[4-(3-chloro-2-methylphenylmethyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e), a novel calmodulin antagonist, and the N-methyl-d-aspartate (NMDA) receptor antagonist MK-801, are capable of attenuating increased serum S-100b levels and brain edema. In contrast, the hyperosmolar agent glycerol, which has no direct neuroprotective action, had little effect on serum S-100b levels, despite a significant decrease in brain water content. These results suggest that lowering of serum S-100b is mediated by neuroprotection against ischemic brain injury. Thus, serum S-100b reflects the extent of brain damage following cerebral ischemia and serves as a useful biomarker for the assessment of neuroprotectants.
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- 2004
10. DY-9760e, a Novel Calmodulin Antagonist, Reduces Infarction after Permanent Focal Cerebral Ischemia in Rats
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Toshiyuki Sato, Hideo Takamori, and Yasufumi Shirasaki
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Male ,Middle Cerebral Artery ,Indazoles ,Time Factors ,Calmodulin ,Drug Evaluation, Preclinical ,Ischemia ,Infarction ,Pharmacology ,Loading dose ,Neuroprotection ,Drug Administration Schedule ,Brain Ischemia ,Japan ,medicine ,Animals ,Infusions, Intravenous ,Dose-Response Relationship, Drug ,biology ,business.industry ,Antagonist ,Infarction, Middle Cerebral Artery ,Recovery of Function ,General Medicine ,medicine.disease ,Rats, Inbred F344 ,Rats ,Disease Models, Animal ,Dy 9760e ,Neuroprotective Agents ,Anesthesia ,Infarct volume ,biology.protein ,business - Abstract
DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate), a novel calmodulin antagonist, provides effective protection against Ca2+ ionophore-induced cytotoxicity and brain injury induced by transient focal ischemia. In this study, we evaluated the effect of DY-9760e on ischemic infarct volume in rats subjected to permanent focal ischemia. DY-9760e (0.5 mg/kg/h for 6 h) significantly reduced the infarct volume when administered immediately after middle cerebral artery occlusion. Furthermore, this neuroprotection was also exerted by treatment with a 3-hour delay, implying that the therapeutic time window for this compound is at least 3 h. In addition, although treatment with 0.1 mg/kg/h for 24 h was ineffective, the combination of a loading dose of 0.3 mg/kg/h for 2 h followed by 0.1 mg/kg/h for 22 h yielded a significant reduction in infarct volume. Thus, prolonged infusion preceded by a loading dose is an efficacious dosing regimen for DY-9760e, especially at a low infusion rate. These data demonstrate the substantial neuroprotective effect of DY-9760e in a permanent focal ischemia model and indicate that this neuroprotectant may be of therapeutic value for the treatment of acute stroke.
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- 2004
11. 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, Reduces Brain Edema through the Inhibition of Enhanced Blood-Brain Barrier Permeability after Transient Focal Ischemia
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Toshiyuki Sato, Yoshiyuki Morishima, and Yasufumi Shirasaki
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Male ,Cell Membrane Permeability ,Indazoles ,Calmodulin ,Brain Edema ,Trifluoperazine ,Pharmacology ,chemistry.chemical_compound ,Animals ,Medicine ,Rats, Wistar ,Stroke ,Barrier function ,Evans Blue ,biology ,business.industry ,Antagonist ,Water ,medicine.disease ,Extravasation ,Rats ,Endothelial stem cell ,Disease Models, Animal ,chemistry ,Blood-Brain Barrier ,Ischemic Attack, Transient ,Anesthesia ,biology.protein ,Molecular Medicine ,Endothelium, Vascular ,business ,medicine.drug - Abstract
An alteration of the blood-brain barrier (BBB) permeability contributes to the development of brain edema after stroke. In this study, we evaluated 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 brain edema formation and BBB integrity in rats subjected to transient focal ischemia. DY-9760e (1 mg/kg/h) was intravenously infused for 6 h, starting immediately after reperfusion of a 1-h middle cerebral artery occlusion. Treatment with DY-9760e significantly suppressed the increase in water content and the extravasation of Evans blue dye after transient focal ischemia. Analysis of a magnetic resonance imaging method revealed that DY-9760e significantly prevented the development of brain edema in the cortical region of the ipsilateral hemisphere. Trifluoperazine, a calmodulin antagonist that is structurally different from DY-9760e, also attenuated brain edema elicited by transient focal ischemia. Furthermore, DY-9760e and trifluoperazine reduced tumor necrosis factor-alpha-induced hyperpermeability of inulin through a cultured brain microvascular endothelial cell monolayer, suggesting an involvement of calmodulin in the regulation of brain microvascular barrier function. The present results demonstrate that DY-9760e ameliorates brain edema formation and suggest that this effect may be mediated in part by the inhibition of enhanced BBB permeability after ischemic insults. Thus, DY-9760e is expected to be a therapeutic drug for treatment of acute stroke patients.
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- 2002
12. DY-9760e, a novel calmodulin antagonist, reduces brain damage induced by transient focal cerebral ischemia
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Yoshiyuki Morishima, Yasufumi Shirasaki, Toshiyuki Sato, Toshihiro Uchida, and Masunobu Sugimura
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Male ,medicine.medical_specialty ,Indazoles ,Cerebral arteries ,Central nervous system ,Ischemia ,Blood Pressure ,Nerve Tissue Proteins ,Constriction, Pathologic ,Brain damage ,Brain Ischemia ,Brain ischemia ,Calmodulin ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Infusions, Intravenous ,Cerebral Cortex ,Pharmacology ,business.industry ,Cerebral infarction ,Microfilament Proteins ,Antagonist ,Cerebral Arteries ,medicine.disease ,Corpus Striatum ,Rats ,Endocrinology ,medicine.anatomical_structure ,Cerebral cortex ,Anesthesia ,medicine.symptom ,Carrier Proteins ,business - Abstract
Perturbations in Ca2+ homeostasis have been proposed to lead to neuronal damage after cerebral ischemia. DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1- (4-imidazolylethyl)-1H-indazole dihydrochloride 3.5 hydrate) is a novel calmodulin antagonist. In this study, we examined the effects of DY-9760e on brain damage in rats subjected to transient (1 h) focal cerebral ischemia. DY-9760e (0.25-1.00 mg kg(-1) h(-1)) was intravenously infused for 6 h, starting 1 h after middle cerebral artery occlusion. Treatment with DY-9760e 0.25, 0.50 and 1.00 mg kg(-1) h(-1) reduced infarct volume by 30, 42 (P < 0.05), and 60% (P < 0.05), respectively. Furthermore, the effect of DY-9760e on ischemia-induced fodrin breakdown was examined in the same model. Pronounced fodrin breakdown was observed in the cerebral cortex and striatum at 24 h after ischemia. DY-9760e caused potent suppression of fodrin breakdown in the cerebral cortex at the same doses as those that had a protective action against cerebral infarction. From these results DY-9760e may have a therapeutic effect against cerebral ischemic damage in the acute stage.
- Published
- 1999
13. Effect of physical restraint on glucose tolerance in cynomolgus monkeys
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Kanpei Kanazawa, Naoya Yoshioka, Toshiaki Hayashi, Tadahiro Horikawa, Tsuyoshi Maekawa, and Yasufumi Shirasaki
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Blood Glucose ,Restraint, Physical ,medicine.medical_specialty ,Plasma glucose ,Glucose tolerance test ,General Veterinary ,medicine.diagnostic_test ,business.industry ,Glucose challenge ,Glucose Tolerance Test ,Macaca fascicularis ,Endocrinology ,Stress, Physiological ,Internal medicine ,medicine ,Animals ,Animal Science and Zoology ,Female ,business - Abstract
Background Physiologic stress has been demonstrated to impair glucose tolerance. Methods Glucose tolerance tests were performed using six cynomolgus monkeys. Results Chair-restrained subjects elicited higher elevations of plasma glucose and cortisol compared with squeezing device-restrained subjects. Conclusions The responses to a glucose challenge are altered by different restraint procedures.
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- 2013
14. Protection of Neurovascular Injury by Vasoprotective Agents: A Novel Therapeutic Strategy for Ischemic Brain Edema
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Feng Han, Norifumi Shioda, Yasufumi Shirasaki, and Kohji Fukunaga
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- 2012
15. Protein kinase C subspecies in hippocampus and striatum of reserpinized rat brain
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Katsuhiko Yanagisawa, Tadashi Miyatake, Yasufumi Shirasaki, and Hiroshi Komachi
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Male ,medicine.medical_specialty ,Reserpine ,Central nervous system ,Hippocampus ,Striatum ,Biology ,Western blot ,Biogenic amine ,Internal medicine ,medicine ,Animals ,Biogenic Monoamines ,Rats, Wistar ,Molecular Biology ,Protein Kinase C ,Protein kinase C ,chemistry.chemical_classification ,medicine.diagnostic_test ,General Neuroscience ,Corpus Striatum ,Rats ,Cytosol ,Endocrinology ,medicine.anatomical_structure ,nervous system ,chemistry ,Neurology (clinical) ,Developmental Biology ,medicine.drug - Abstract
Protein kinase C (PKC) (alpha) and (beta) immunoreactivities were determined in the cytosolic and particulate fractions of the hippocampus and striatum after single and repetitive, intraperitoneal administration of reserpine. Significant decrease of PKC(alpha) immunoreactivities was observed in the particulate fractions of both striatum and hippocampus. Compared with the alteration of PKC(alpha), the decreased immunoreactivity of PKC(beta) was only observed in the particulate fraction of the hippocampus, associated with the increase in the cytosolic fraction. These findings suggest a novel mechanism regulating the distribution of PKC. The topographical selectivity in the present study may indicate the importance of the alteration of PKC(beta) in the pathophysiological mechanism in Alzheimer's disease.
- Published
- 1994
16. CaMKIIδB mediates aberrant NCX1 expression and the imbalance of NCX1/SERCA in transverse aortic constriction-induced failing heart
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Xiao-Ming Li, Kohji Fukunaga, Feng Han, Ying Mei Lu, Norifumi Shioda, Ji-Yun Huang, and Yasufumi Shirasaki
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Male ,lcsh:Medicine ,Cardiovascular ,Biochemistry ,Mice ,Drug Discovery ,Molecular Cell Biology ,Myocyte ,lcsh:Science ,Lung ,Crosstalk ,Apoptotic Signaling Cascade ,Multidisciplinary ,biology ,Chemistry ,Mechanisms of Signal Transduction ,Heart ,Organ Size ,Immunohistochemistry ,Signaling Cascades ,Cytochemistry ,cardiovascular system ,Medicine ,Immunocytochemistry ,Research Article ,Signal Transduction ,Mef2 ,medicine.medical_specialty ,SERCA ,Calmodulin ,Blotting, Western ,Aortic Diseases ,Signaling Pathways ,Sodium-Calcium Exchanger ,Cardiovascular Pharmacology ,Sarcoplasmic Reticulum Calcium-Transporting ATPases ,Ca2+/calmodulin-dependent protein kinase ,Internal medicine ,Calcium-Mediated Signal Transduction ,medicine ,Animals ,Protein Interactions ,Biology ,Heart Failure ,Sodium-calcium exchanger ,Body Weight ,lcsh:R ,Proteins ,medicine.disease ,Transmembrane Proteins ,Endocrinology ,Calcium Signaling Cascade ,Heart failure ,biology.protein ,Calcium ,lcsh:Q ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 ,Homeostasis - Abstract
Ca2+/calmodulin-dependent protein kinase II δB (CaMKIIδB) is one of the predominant isoforms of CaMKII in the heart. The precise role of CaMKIIδB in the transcriptional cross-talk of Ca2+-handling proteins during heart failure remains unclear. In this work, we aim to determine the mechanism of CaMKIIδB in modulating the expression of sarcolemmal Na+–Ca2+ exchange (NCX1). We also aim to address the potential effects of calmodulin antagonism on the imbalance of NCX1 and sarcoendoplasmic reticulum Ca2+ ATPase (SERCA) during heart failure. Eight weeks after transverse aortic constriction (TAC)-induced heart failure in mice, we found that the heart weight/tibia length (HW/TL) ratio and the lung weight/body weight (LW/BW) ratio increased by 59% and 133%, respectively. We further found that the left ventricle-shortening fraction decreased by 40% compared with the sham-operated controls. Immunoblotting revealed that the phosphorylation of CaMKIIδB significantly increased 8 weeks after TAC-induced heart failure. NCX1 protein levels were also elevated, whereas SERCA2 protein levels decreased in the same animal model. Moreover, transfection of active CaMKIIδB significantly increased NCX1 protein levels in adult mouse cardiomyocytes via class IIa histone deacetylase (HDAC)/myocyte enhancer factor-2 (MEF2)-dependent signaling. In addition, pharmacological inhibition of calmodulin/CaMKIIδB activity improved cardiac function in TAC mice, which partially normalized the imbalance between NCX1 and SERCA2. These data identify NCX1 as a cellular target for CaMKIIδB. We also suggest that the CaMKIIδB-induced imbalance between NCX1 and SERCA2 is partially responsible for the disturbance of intracellular Ca2+ homeostasis and the pathological process of heart failure.
- Published
- 2011
17. Inhibition of dystrophin breakdown and endothelial nitric-oxide synthase uncoupling accounts for cytoprotection by 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e) in left ventricular hypertrophied Mice
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Hideyuki Hasegawa, Kohji Fukunaga, Hiroshi Kanai, Erika Hachimura, Yasufumi Shirasaki, Ying Mei Lu, and Feng Han
- Subjects
Male ,medicine.medical_specialty ,Cardiotonic Agents ,Indazoles ,Nitric Oxide Synthase Type III ,Caveolin 3 ,Mice, Inbred Strains ,Muscle hypertrophy ,Dystrophin ,chemistry.chemical_compound ,Mice ,Atrial natriuretic peptide ,Enos ,Internal medicine ,medicine ,Animals ,Glycoproteins ,Pharmacology ,Pressure overload ,Heart Failure ,biology ,Dose-Response Relationship, Drug ,Chemistry ,Myocardium ,Spectrin ,Calpain ,Heart ,biology.organism_classification ,medicine.disease ,Cytoprotection ,Disease Models, Animal ,Endocrinology ,Heart failure ,biology.protein ,Molecular Medicine ,Hypertrophy, Left Ventricular ,Peroxynitrite ,Atrial Natriuretic Factor - Abstract
Using a heart ischemia/reperfusion model in rats, we recently demonstrated that 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 calmodulin inhibitor, is a cardioprotective drug. Here, we examined cardioprotective mechanisms of DY-9760e in hypertrophy and heart failure using a mouse transverse aortic constriction (TAC) model. Mice were subjected to TAC and 2 weeks later they were administered DY-9760e for another 6 weeks (at 10 or 20 mg/kg/day p.o.). Chronic administration inhibited TAC-induced increased heart-to-body weight ratio dose-dependently. Consistent with inhibition of hypertrophy, fraction shortening, an indicator of heart contractile function, assessed by echocardiography was completely restored by DY-9760e (20 mg/kg/day) administration. Inhibition of TAC-induced atrial natriuretic peptide (ANP) up-regulation further confirmed an antihypertrophic effect of DY-9760e. It is noteworthy that we found that breakdown of dystrophin and spectrin by calpain was associated with heart failure in TAC mice. Caveolin-3 breakdown was closely associated with endothelial nitric-oxide synthase (eNOS) dissociation from the plasma membrane and its subsequent uncoupling. Uncoupled monomeric eNOS formation was associated with increased protein tyrosine nitration, suggesting peroxynitrite production and NO and superoxide formation. It is important to note that 6 weeks of DY-9760e treatment significantly blocked hypertrophic responses, such as increased heart weight and ANP induction. Overall, we show that inhibition of both dystrophin/spectrin breakdown and uncoupling of eNOS probably underlies the cardioprotective mechanisms of DY-9760e. The observed protection of sarcolemmal proteins and eNOS by DY-9760e during pressure overload suggests a novel therapeutic strategy to rescue the heart from hypertrophy-induced failure.
- Published
- 2009
18. DY-9760e inhibits endothelin-1-induced cardiomyocyte hypertrophy through inhibition of CaMKII and ERK activities
- Author
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Zheng-Hong Qin, Akifumi Kamata, Yasufumi Shirasaki, Kohji Fukunaga, Ying Mei Lu, Feng Han, and Norifumi Shioda
- Subjects
MAPK/ERK pathway ,Benzylamines ,Time Factors ,Muscle hypertrophy ,Atrial natriuretic peptide ,Natriuretic Peptide, Brain ,Medicine ,Pharmacology (medical) ,Myocytes, Cardiac ,Phosphorylation ,Extracellular Signal-Regulated MAP Kinases ,Calcimycin ,Cells, Cultured ,Sulfonamides ,biology ,Endothelin-1 ,Kinase ,MEK inhibitor ,General Medicine ,Cell biology ,Mitogen-activated protein kinase ,cardiovascular system ,Cardiology and Cardiovascular Medicine ,Atrial Natriuretic Factor ,DNA Replication ,medicine.medical_specialty ,Indazoles ,Cardiomegaly ,Transfection ,Internal medicine ,Ca2+/calmodulin-dependent protein kinase ,Nitriles ,Butadienes ,Animals ,Calcium Signaling ,RNA, Messenger ,Rats, Wistar ,Protein Kinase Inhibitors ,Cell Proliferation ,Cell Size ,Pharmacology ,Ionophores ,business.industry ,Endothelin 1 ,Rats ,Endocrinology ,Animals, Newborn ,biology.protein ,business ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 - Abstract
Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and extracellular signal-regulated kinase (ERK) have pivotal roles in endothelin-1 (ET-1)-induced cardiomyocyte hypertrophy. We here tested whether a novel CaM antagonist, DY-9760e inhibits ET-1-induced hypertrophy through inhibition of CaMKII and ERK activities. We first confirmed that Ca(2+) oscillation induced by ET-1 treatment elicits transient activation of CaMKII and ERK in cultured cardiomyocytes. DY-9760e treatment with 3 microM totally and partially inhibited the ET-1-induced CaMKII and ERK activation, respectively. The ET-1-induced ERK activation was also partially blocked by a CaMKII inhibitor, KN93. To confirm involvement of CaMKII activity in the ERK activation by ET-1 and A23187, cultured cardiomyocytes were transfected with a constitutively active CaMKII. The transfection with the active CaMKII elicited ERK activation in cultured cardiomyocytes and cotransfection with dominant negative CaMKII eliminated its ERK activation. Consistent with inhibitory actions of DY-9760e on the ET-1-induced CaMKII and ERK activation, induction of hypertrophy-related genes including atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) was significantly inhibited by DY-9760e treatment. Combination treatment with DY-9760e and U0126, a MEK inhibitor, totally blocked the ET-1-induced ANP and BNP expression. DY-9760e treatment (3 microM) significantly inhibited the ET-1-induced hypertrophy and combination treatment with DY-9760e and U0126 totally blocked the ET-1-induced hypertrophy in cultured cardiomyocytes. These results suggest that DY-9760e elicits antihypertrophic action on ET-1-induced cardiac hypertrophy through inhibition of CaMKII and ERK activation and that CaMKII activity in part mediates ET-1-induced ERK activation.
- Published
- 2009
19. Imbalance between CaM kinase II and calcineurin activities impairs caffeine-induced calcium release in hypertrophic cardiomyocytes
- Author
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Yasufumi Shirasaki, Shigeki Moriguchi, Kohji Fukunaga, Jiro Kasahara, Zheng-Hong Qin, Norifumi Shioda, Ying Mei Lu, and Feng Han
- Subjects
medicine.medical_specialty ,Indazoles ,Cardiomegaly ,Biochemistry ,Muscle hypertrophy ,Phenylephrine ,Ca2+/calmodulin-dependent protein kinase ,Internal medicine ,Calcium-binding protein ,medicine ,Animals ,Phosphorylation ,Rats, Wistar ,Cells, Cultured ,Pharmacology ,Endothelin-1 ,Chemistry ,Angiotensin II ,Calcineurin ,Autophosphorylation ,Calcium-Binding Proteins ,musculoskeletal system ,Immunohistochemistry ,Phospholamban ,Rats ,Endocrinology ,cardiovascular system ,Calcium ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 - Abstract
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.
- Published
- 2007
20. Microsphere embolism-induced endothelial nitric oxide synthase expression mediates disruption of the blood-brain barrier in rat brain
- Author
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Yasufumi Shirasaki, Kohji Fukunaga, and Feng Han
- Subjects
Indazoles ,Endothelium ,Nitric Oxide Synthase Type III ,Embolism ,Biology ,Blood–brain barrier ,Biochemistry ,Brain Ischemia ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,Calmodulin ,Enos ,medicine ,Animals ,Tyrosine ,Evans Blue ,Brain ,biology.organism_classification ,Molecular biology ,Immunohistochemistry ,Microspheres ,Rats ,Endothelial stem cell ,Nitric oxide synthase ,medicine.anatomical_structure ,chemistry ,Blood-Brain Barrier ,Cerebrovascular Circulation ,Enzyme Induction ,biology.protein ,Endothelium, Vascular ,Peroxynitrite - Abstract
Microsphere embolism (ME)-induced up-regulation of endothelial nitric oxide synthase (eNOS) in endothelial cells of brain microvessels was observed 2-48 h after ischemia. eNOS induction preceded disruption of the blood-brain barrier (BBB) observed 6-72 h after ischemia. In vascular endothelial cells, ME-induced eNOS expression was closely associated with protein tyrosine nitration, which is a marker of generation of peroxynitrite. Leakage of rabbit IgG from microvessels was also evident around protein tyrosine nitration-immunoreactive microvessels. To determine whether eNOS expression and protein tyrosine nitration in vascular endothelial cells mediates BBB disruption in the ME brain, we tested the effect of a novel calmodulin-dependent NOS inhibitor, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e), which inhibits eNOS activity and, in turn, protein tyrosine nitration. Concomitant with inhibition of protein tyrosine nitration in vascular endothelial cells, DY-9760e significantly inhibited BBB disruption as assessed by Evans blue (EB) excretion. DY-9760e also inhibited cleavage of poly (ADP-ribose) polymerase as a marker of the apoptotic pathway in vascular endothelial cells. Taken together with previous evidence in which DY-9760e inhibited brain edema, ME-induced eNOS expression in vascular endothelial cells likely mediates BBB disruption and, in turn, brain edema.
- Published
- 2006
21. Inhibition of nitric oxide production and protein tyrosine nitration contribute to neuroprotection by a novel calmodulin antagonist, DY-9760e, in the rat microsphere embolism
- Author
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Norifumi Shiota, Jiro Kasahara, Kohji Fukunaga, Takashi Shirakura, Shigeki Moriguchi, Toshiyuki Sato, Yasufumi Shirasaki, and Feng Han
- Subjects
Indazoles ,Microdialysis ,Blotting, Western ,Ischemia ,Pharmaceutical Science ,Brain damage ,Pharmacology ,Gerbil ,Nitric Oxide ,Neuroprotection ,Nitric oxide ,Brain ischemia ,chemistry.chemical_compound ,Calmodulin ,medicine ,Animals ,Nitrates ,Antagonist ,Brain ,General Medicine ,Cerebral Infarction ,medicine.disease ,Microspheres ,Rats ,Neostriatum ,Neuroprotective Agents ,chemistry ,Biochemistry ,Intracranial Embolism ,Tyrosine ,medicine.symptom ,Peroxynitrite ,Injections, Intraperitoneal - Abstract
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.
- Published
- 2005
22. 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
- Author
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Masami Hashimoto, Yasufumi Shirasaki, Kohji Fukunaga, Jiro Kasahara, Hiroaki Hisa, Yoko Takada, and Yusuke Takeuchi
- Subjects
Male ,Indazoles ,Calmodulin ,Blotting, Western ,Ischemia ,Caspase 3 ,Myocardial Reperfusion Injury ,Pharmacology ,Ventricular Function, Left ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,medicine ,Animals ,Evans Blue ,Indazole ,biology ,Chemistry ,lcsh:RM1-950 ,Microfilament Proteins ,Antagonist ,Proteins ,Calpain ,medicine.disease ,Caspase Inhibitors ,Rats ,Enzyme Activation ,lcsh:Therapeutics. Pharmacology ,Biochemistry ,Coronary occlusion ,Caspases ,biology.protein ,Molecular Medicine ,Tyrosine ,Carrier Proteins - Abstract
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. Keywords:: cardiomyocyte, coronary occlusion, calmodulin antagonist, calpain, caspase-3
- Published
- 2005
23. DY-9760e, a calmodulin antagonist, reduces brain damage after permanent focal cerebral ischemia in cats
- Author
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Hiromichi Fukushi, Hideo Takamori, Yoshito Kanazawa, Yutaka Kitano, Masunobu Sugimura, and Yasufumi Shirasaki
- Subjects
Male ,Telencephalon ,medicine.medical_specialty ,Indazoles ,Ischemia ,Pharmaceutical Science ,Brain damage ,Brain Ischemia ,Brain ischemia ,Calmodulin ,Internal medicine ,medicine.artery ,medicine ,Animals ,Hypoxia, Brain ,Pharmacology ,Dose-Response Relationship, Drug ,business.industry ,Cerebrum ,Penumbra ,Antagonist ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Cerebral cortex ,Anesthesia ,Middle cerebral artery ,Cardiology ,Cats ,medicine.symptom ,business - Abstract
DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate), a calmodulin antagonist, provides protection against Ca(2+) overload-associated cytotoxicity and brain injury after cerebral ischemia in rats. In this study, we assessed the effect of DY-9760e on ischemic infarct volume in cats subjected to permanent focal cerebral ischemia. DY-9760e was infused for 6 h, beginning 5 min after occlusion of the middle cerebral artery. The infarct volume was measured at the end of drug infusion. DY-9760e, at the dose of 0.25 but not 0.1 mg/kg/h, significantly reduced cerebral infarct volume without affecting any physiological parameters, and its protective effect was mainly evident in the cerebral cortex, where the penumbra, a salvageable zone, exists. The present study demonstrates that DY-9760e protects against brain injury after focal ischemia in a gyrencephalic animal as well as in the rodents reported previously and suggests its therapeutic value for the treatment of acute stroke.
- Published
- 2005
24. Protective effect of DY-9760e, a calmodulin antagonist, against neuronal cell death
- Author
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Hiromichi Takano, Yoshiyuki Morishima, Yoshito Kanazawa, Yasufumi Shirasaki, Masunobu Sugimura, and Toshihiro Uchida
- Subjects
Programmed cell death ,Thapsigargin ,Indazoles ,N-Methylaspartate ,Patch-Clamp Techniques ,Calmodulin ,Excitotoxicity ,Pharmaceutical Science ,Glutamic Acid ,Calcium-Transporting ATPases ,medicine.disease_cause ,Endoplasmic Reticulum ,Sodium Channels ,Potassium Chloride ,chemistry.chemical_compound ,medicine ,Animals ,Cells, Cultured ,Pharmacology ,Neurons ,Veratridine ,biology ,Cell Death ,Dose-Response Relationship, Drug ,Endoplasmic reticulum ,Glutamate receptor ,General Medicine ,Cell biology ,Rats ,Neuroprotective Agents ,chemistry ,biology.protein ,Calcium ,Calcium Channels ,Ion Channel Gating ,Intracellular - Abstract
An excessive elevation of intracellular Ca(2+) levels is known to play a key role in the pathological events following cerebral ischemia. DY-9760e, 3-[2-[4-(3-chloro-2-methylphenylmethyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, is a potent calmodulin antagonist that attenuates brain damage in focal ischemia models. In the present study, we investigated the effect of DY-9760e on neuronal cell death induced by a variety of cell-toxic stimuli that increase intracellular Ca(2+). Cell death was induced by the exposure of primary cultured neurons to excitotoxic agents such as glutamate and N-methyl-D-aspartate, membrane-depolarizing agents such as veratridine and high KCl, or thapsigargin an endoplasmic reticulum Ca(2+)-ATPase inhibitor. Treatment with DY-9760e resulted in a dose-dependent prevention of neuronal cell death elicited by excitotoxicity, voltage-gated channel opening, and inhibition of endoplasmic reticulum Ca(2+)-ATPase. These results indicate that DY-9760e can rescue neurons from various types of cell-toxic stimuli, which may contribute to attenuation of brain injury after cerebral ischemia.
- Published
- 2004
25. The post-ischemic administration 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, prevents delayed neuronal death in gerbil hippocampus
- Author
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Motohiro Morioka, Kohji Fukunaga, Shigetoshi Yano, Akihito Hashiguchi, Masato Kochi, Jun-ichiro Hamada, and Yasufumi Shirasaki
- Subjects
Male ,medicine.medical_specialty ,Indazoles ,Calmodulin ,Calcium-Calmodulin-Dependent Protein Kinase Kinase ,Protein Serine-Threonine Kinases ,Gerbil ,Neuroprotection ,Hippocampus ,Brain Ischemia ,chemistry.chemical_compound ,Internal medicine ,Ca2+/calmodulin-dependent protein kinase ,medicine ,Animals ,Pharmacology ,Neurons ,biology ,Cell Death ,Nitrotyrosine ,lcsh:RM1-950 ,Antagonist ,Calcineurin ,Endocrinology ,lcsh:Therapeutics. Pharmacology ,chemistry ,biology.protein ,Molecular Medicine ,Gerbillinae ,Peroxynitrite - Abstract
The novel calmodulin (CaM) antagonist DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate) with an apparent neuroprotective effect in vivo preferentially inhibits neuronal nitric oxide synthase (nNOS), Ca2+/CaM-dependent protein kinase IIα (CaMKIIα), and calcineurin in vitro. In the present study, we investigated the molecular mechanism underlying its neuroprotective effect with the gerbil transient forebrain ischemia model, by focusing on its inhibition of these Ca2+/CaM-dependent enzymes. Post-ischemic DY-9760e treatment (5 mg/kg, i.p.) immediately after 5-min ischemia significantly reduced the delayed neuronal death in the hippocampal CA1 region. CaMKIIα was transiently autophosphorylated immediately after reperfusion with concomitant sustained decrease in its total amounts in the Triton X-100-soluble fractions. Calcineurin activity, accessed by the phosphorylation state of dopamine- and cAMP-regulated phosphoprotein of Mr 32,000 (DARPP-32) at Thr34, was elevated at 6 h after reperfusion. Post-treatment of DY-9760e had no effects on both CaMKIIα and DARPP-32 phosphorylation at 6 h after reperfusion. However, DY-9760e significantly inhibited nitrotyrosine formation, as a biomarker of NO, and in turn, peroxynitrite (ONOO-) production. These results suggest that DY-9760e primarily inhibits Ca2+/CaM-dependent neuronal NOS, without any effects on CaMKII and calcineurin, and the inhibition of NO production possibly accounts for its neuroprotective action in brain ischemic injury. Keywords:: cerebral ischemia, nitric oxide synthase (NOS), Ca2+/calmodulin-dependent protein kinase II (CaMKII), calcineurin, dopamine- and cAMP-regulated phosphoprotein of Mr 32,000 (DARPP-32)
- Published
- 2004
26. The neuroprotective effect of a novel calmodulin antagonist, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, in transient forebrain ischemia
- Author
-
Motohiro Morioka, Yukitaka Ushio, Akihito Hashiguchi, Yasufumi Shirasaki, Kohji Fukunaga, Takayuki Kawano, T Sato, Shigetoshi Yano, and J. Hamada
- Subjects
Male ,Microdialysis ,Indazoles ,Time Factors ,Blotting, Western ,Carotid Artery, Internal, Dissection ,Pharmacology ,Nitric Oxide ,Neuroprotection ,Hippocampus ,Nitric oxide ,Brain Ischemia ,chemistry.chemical_compound ,Calmodulin ,In vivo ,Animals ,Enzyme Inhibitors ,Chromatography, High Pressure Liquid ,biology ,General Neuroscience ,Nitrotyrosine ,Antagonist ,Immunohistochemistry ,Nitric oxide synthase ,Disease Models, Animal ,NG-Nitroarginine Methyl Ester ,Neuroprotective Agents ,chemistry ,Ischemic Attack, Transient ,Anesthesia ,Reperfusion ,biology.protein ,Tyrosine ,Gerbillinae ,Peroxynitrite - Abstract
A novel calmodulin (CaM) antagonist DY-9760e, (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1 H -indazole dihydrochloride 3.5 hydrate), with an apparent neuroprotective effect in vivo , potently inhibits CaM-dependent nitric oxide synthase in situ . In the present study, we determined whether DY-9760e inhibits nitric oxide (NO) production and protein nitration by peroxynitrite (ONOO − ) formation in the hippocampal CA1 region of gerbils after transient forebrain ischemia. In freely moving gerbils, NO production after 10-minute forebrain ischemia was monitored consecutively with in vivo brain microdialysis. Pretreatment with DY-9760e (50 mg/kg i.p.) significantly decreased the increased levels of NO x − (NO metabolites, NO 2 − plus NO 3 − ) immediately after, 24 h after cerebral ischemia-reperfusion to the control levels of sham-operated animals. Western blot and immunohistochemical analyses using an anti-nitrotyrosine antibody as a marker of ONOO − formation indicated a marked increase in nitrotyrosine immunoreactivity in the pyramidal neurons of the CA1 region 2 h after reperfusion, and DY-9760e significantly inhibited increased nitrotyrosine immunoreactivity. Coincident with the inhibition of the NO production and protein tyrosine nitration, pretreatment with DY-9760e rescued the delayed neuronal death in the hippocampal CA1 region. These results suggest that the inhibitory effects of DY-9760e on the NO-ONOO − pathway partly account for its neuroprotective effects in cerebral ischemia.
- Published
- 2003
27. Calmodulin and calmodulin-dependent kinase II mediate neuronal cell death induced by depolarization
- Author
-
Yoshiyuki Morishima, Hiromichi Takano, Hiromichi Fukushi, and Yasufumi Shirasaki
- Subjects
medicine.medical_specialty ,Programmed cell death ,Benzylamines ,Calmodulin ,Nifedipine ,Biology ,Tacrolimus ,Membrane Potentials ,chemistry.chemical_compound ,Fetus ,Ca2+/calmodulin-dependent protein kinase ,Internal medicine ,1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine ,Nitriles ,Pyrethrins ,medicine ,Animals ,Enzyme Inhibitors ,Protein kinase A ,Molecular Biology ,Egtazic Acid ,Cells, Cultured ,Cerebral Cortex ,Neurons ,Sulfonamides ,Veratridine ,Cell Death ,General Neuroscience ,Depolarization ,Trifluoperazine ,Cell biology ,Rats ,Nitric oxide synthase ,Kinetics ,medicine.anatomical_structure ,Endocrinology ,NG-Nitroarginine Methyl Ester ,nervous system ,chemistry ,Calcium-Calmodulin-Dependent Protein Kinases ,biology.protein ,Neurology (clinical) ,Neuron ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 ,Developmental Biology - Abstract
Depolarization has been known to play an important role in the neuronal damage that occurs following cerebral ischemia. In the present study, we investigated the roles of calmodulin (CaM) and CaM-dependent enzymes in depolarization-induced neuronal cell death. Treatment of primary cortical neurons with 10 microM veratridine, a voltage sensitive Na(+) channel activator, induced cell death as indicated by lactate dehydrogenase leakage from neurons. CaM antagonists (calmidazolium, trifluoperazine, W-7, and W-5) inhibited cell death induced by veratridine in a concentration-dependent manner. CaM kinase II (CaMKII) inhibitors (KN-62, KN-93, and myristoylated autocamtide-2 related inhibitory peptide), but not inhibitors of nitric oxide synthase or calcineurin, prevented veratridine-induced neuronal cell death. Veratridine rapidly activated CaMKII in neurons, and CaM antagonists and a CaMKII inhibitor suppressed the CaMKII activation. These results suggest that the CaM-CaMKII pathway contributes to depolarization-evoked cell death in neurons.
- Published
- 2003
28. Reduced membrane-associated protein kinase C(β) immunoreactivity in the hippocampus of reserpinized rat brain
- Author
-
Katsuhiko Yanagisawa, Tadashi Miyatake, Yasufumi Shirasaki, and Hiroshi Komachi
- Subjects
Male ,medicine.medical_specialty ,Cerebellum ,Reserpine ,Immunoblotting ,Central nervous system ,Hippocampus ,Biology ,Western blot ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Protein kinase A ,Protein Kinase C ,Protein kinase C ,Membranes ,medicine.diagnostic_test ,General Neuroscience ,Brain ,Rats ,Cytosol ,medicine.anatomical_structure ,Endocrinology ,nervous system ,Subcellular Fractions ,medicine.drug - Abstract
Protein kinase C(β) immunoreactivity was determined in the membrane and cytosol fractions of the hippocampus, frontal cortex and cerebellum after repetitive, intraperitoneal administration of reserpine. A marked decrease in the immunoreactivity was observed in the membrane of the hippocampus, while no significant change was found in any other subfractions of the frontal cortex or cerebellum. These findings suggest a novel mechanism regulating the distribution of protein kinase C. The topographical selectivity in the present study may indicate the importance of the alteration of protein kinase C in the pathophysiological mechanism in Alzheimer's disease.
- Published
- 1993
29. β-Amyloid Induces Neuronal Apoptosis Via a Mechanism that Involves the c-Jun N-Terminal Kinase Pathway and the Induction of Fas Ligand
- Author
-
Hiromichi Takano, Yoshiyuki Morishima, Richard A. Flavell, Michael E. Greenberg, Yukiko Gotoh, Janine Zieg, Yasufumi Shirasaki, Roger J. Davis, and Tamera Barrett
- Subjects
Programmed cell death ,Fas Ligand Protein ,Transcription, Genetic ,Proto-Oncogene Proteins c-jun ,Apoptosis ,Mice, Inbred Strains ,Biology ,Fas ligand ,Mice ,Alzheimer Disease ,Mitogen-Activated Protein Kinase 10 ,Animals ,Rats, Long-Evans ,Senile plaques ,fas Receptor ,Cognitive decline ,ARTICLE ,Phosphorylation ,Transcription factor ,Cells, Cultured ,Mice, Knockout ,Neurons ,Amyloid beta-Peptides ,Membrane Glycoproteins ,General Neuroscience ,c-jun ,JNK Mitogen-Activated Protein Kinases ,Protein-Tyrosine Kinases ,Cell biology ,Rats ,Enzyme Activation ,Gene Expression Regulation ,Signal transduction ,Mitogen-Activated Protein Kinases ,Signal Transduction - Abstract
Elevated levels of beta-Amyloid (Abeta) are present in the brains of individuals with either the sporadic or familial form of Alzheimer's disease (AD), and the deposition of Abeta within the senile plaques that are a hallmark of AD is thought to be a primary cause of the cognitive dysfunction that occurs in AD. Recent evidence suggests that Abeta induces neuronal apoptosis in the brain and in primary neuronal cultures, and that this Abeta-induced neuronal death may be responsible in part for the cognitive decline found in AD patients. In this study we have characterized one mechanism by which Abeta induces neuronal death. We found that in cortical neurons exposed to Abeta, activated c-Jun N-terminal kinase (JNK) is required for the phosphorylation and activation of the c-Jun transcription factor, which in turn stimulates the transcription of several key target genes, including the death inducer Fas ligand. The binding of Fas ligand to its receptor Fas then induces a cascade of events that lead to caspase activation and ultimately cell death. By analyzing the effects of mutations in each of the components of the JNK-c-Jun-Fas ligand-Fas pathway, we demonstrate that this pathway plays a critical role in mediating Abeta-induced death of cultured neurons. These findings raise the possibility that the JNK pathway may also contribute to Abeta-dependent death in AD patients.
- Published
- 2001
30. Post-ischemic administration of DY-9760e, a novel calmodulin antagonist, reduced infarct volume in the permanent focal ischemia model of spontaneously hypertensive rat
- Author
-
Akira Tamura, K. Narita, Toshiyuki Sato, Kiyoshi Takagi, Keiji Sano, and Yasufumi Shirasaki
- Subjects
Brain Infarction ,Male ,Indazoles ,Calmodulin ,Ischemia ,chemistry.chemical_element ,Glutamic Acid ,Calcium ,Brain Ischemia ,Brain ischemia ,Spontaneously hypertensive rat ,Rats, Inbred SHR ,medicine ,Animals ,cardiovascular diseases ,Cerebral Cortex ,biology ,business.industry ,Antagonist ,General Medicine ,medicine.disease ,Arterial occlusion ,Rats ,Neostriatum ,Disease Models, Animal ,medicine.anatomical_structure ,Neuroprotective Agents ,Neurology ,chemistry ,Cerebral cortex ,Anesthesia ,Cerebrovascular Circulation ,Nerve Degeneration ,cardiovascular system ,biology.protein ,Neurology (clinical) ,business - Abstract
We assessed the effect of a novel calmodulin antagonist, DY-9760e (3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate) in a spontaneously hypertensive rat (SHR) permanent focal cerebral ischemia. In experiment I, the left middle cerebral artery was permanently occluded in 62 SHRs. DY-9760e (0.5 mg kg(-1) h(-1)) or vehicle alone were administered continuously i.v. for 6 h, beginning 0, 30, or 60 min after the arterial occlusion. The infarct volume was measured 24 h of ischemia. In experiment II, the effect of DY-9760e on CBF was assessed in 10 SHRs. Administration without a delay resulted in a mean infarct volume of 166.7 +/- 21.0 mm3 (vehicle; n = 10) and 125.1 +/- 31.8 mm3 (DY-9760e; n = 9). Administration with a 30 min delay resulted in a mean infarct volume of 173.2 +/- 32.4 mm3 (vehicle; n = 12) and 143.3 +/- 35.3 mm3 (DY-9760e; n = 11). Dy-9760e significantly reduced the infarct under these conditions (p < 0.05). The administration with a 60 min delay failed to reduce the infarct. DY-9760e had no effect on the CBF. Continuous i.v. administration of DY-9760e reduced infarct volume in a SHR permanent focal ischemia without affecting ischemic CBF.
- Published
- 2001
31. DY-9760e, a novel calmodulin antagonist with cytoprotective action
- Author
-
Masao Omitsu, Koji Fukunaga, Masunobu Sugimura, Toshiyuki Sato, Yoshiyuki Morishima, Wakako Nakayama, Yasufumi Shirasaki, and Eishichi Miyamoto
- Subjects
Pharmacology ,Sulfonamides ,Myosin light-chain kinase ,Indazoles ,Calmodulin ,biology ,Cell Death ,Ionophores ,Calcineurin Inhibitors ,Antagonist ,Phosphodiesterase ,Calpain ,Neuroblastoma ,Biochemistry ,Mechanism of action ,Calcium-Calmodulin-Dependent Protein Kinases ,biology.protein ,medicine ,Tumor Cells, Cultured ,Calcium ,Myosin-light-chain phosphatase ,medicine.symptom ,Protein kinase A ,Calcimycin - Abstract
We report the pharmacological characterization and cytoprotective effect of DY-9760e, 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-( 4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate, a novel antagonist of calmodulin. DY-9760e inhibited calmodulin-dependent enzymes, including calmodulin-dependent protein kinase II and IV, calcineurin, [corrected] calmodulin-dependent phosphodiesterase and myosin light chain kinase with Ki values of 1.4, 12, 2.0, 3.8 and 133 microM, respectively. These antagonistic effects of DY-9760e were more potent than those of W-7, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, another calmodulin antagonist. This compound showed little or no effect on calmodulin-independent enzymes, such as protein kinase A and C and calpain I and II. Analysis of the hydrophobic interaction of DY-9760e with calmodulin by using 2-p-toluidinylnaphthalene-6-sulfonate and 9-anthroylcholine revealed that, like W-7, DY-9760e bound to the hydrophobic regions of calmodulin. The [14C]DY-9760e binding assay indicated that DY-9760e bound to calmodulin at one class of binding site. Finally, DY-9760e substantially protected N1E-115 neuroblastoma cells from cytotoxicity induced by the Ca2+ ionophore, A23187. These results indicate that DY-9760e, a novel calmodulin antagonist, possesses a cytoprotective action and suggest that calmodulin plays a critical role in mediating some of the biochemical events leading to cell death following Ca2+ overload.
- Published
- 1998
32. DY-9760e, a novel neuroprotective agent, inhibits neuronal nitric oxide synthase activity in vitro and in cultured neuroblastoma cells
- Author
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Yasufumi Shirasaki, Masao Ohmitsu, Kohji Fukunaga, Masunobu Sugimura, Toshihiro Uchida, Eishichi Miyamoto, and Toshiyuki Sato
- Subjects
Pharmacology ,Neuroblastoma cell ,Dy 9760e ,Chemistry ,Neuroprotection ,Neuronal Nitric Oxide Synthase ,In vitro ,Cell biology - Published
- 1999
33. Erratum to 'DY-9760e, a novel calmodulin antagonist with cytoprotective action' [Eur. J. Pharmacol. 336 (1997) 99–106]
- Author
-
Yasufumi Shirasaki, Koji Fukunaga, Eishichi Miyamoto, Wakako Nakayama, Masao Omitsu, Masunobu Sugimura, Toshiyuki Sato, and Yoshiyuki Morishima
- Subjects
Pharmacology ,Dy 9760e ,Calmodulin ,biology ,Chemistry ,Stereochemistry ,biology.protein ,Antagonist - Published
- 1998
34. DY-9760e, a novel calmodulin antagonist, attenuates neuronal damage
- Author
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Yasufumi Shirasaki, Toshiyuki Sato, Yoshiyuki Morishima, Toshihiro Uchida, Risako Motohashi, and Masunobu Sugimura
- Subjects
Pharmacology ,Dy 9760e ,Calmodulin ,biology ,Neuronal damage ,Chemistry ,biology.protein ,Biophysics ,Antagonist - Published
- 1997
35. Impairment effect of DM-9384, a new cognition enhancer, on learning deficits in cerebral embolized rats
- Author
-
Fusako Yamada, Yasufumi Shirasaki, Wakako Endo, Satoru Tanaka, and Shinichiro Ashida
- Subjects
Pharmacology ,business.industry ,Medicine ,Cognition ,Enhancer ,business ,Neuroscience - Published
- 1990
36. 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, reduces brain edema through the inhibition of enhanced blood-brain barrier permeability after transient focal ischemia.
- Author
-
Toshiyuki, Sato, Yoshiyuki, Morishima, and Yasufumi, Shirasaki
- Abstract
An alteration of the blood-brain barrier (BBB) permeability contributes to the development of brain edema after stroke. In this study, we evaluated 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 brain edema formation and BBB integrity in rats subjected to transient focal ischemia. DY-9760e (1 mg/kg/h) was intravenously infused for 6 h, starting immediately after reperfusion of a 1-h middle cerebral artery occlusion. Treatment with DY-9760e significantly suppressed the increase in water content and the extravasation of Evans blue dye after transient focal ischemia. Analysis of a magnetic resonance imaging method revealed that DY-9760e significantly prevented the development of brain edema in the cortical region of the ipsilateral hemisphere. Trifluoperazine, a calmodulin antagonist that is structurally different from DY-9760e, also attenuated brain edema elicited by transient focal ischemia. Furthermore, DY-9760e and trifluoperazine reduced tumor necrosis factor-alpha-induced hyperpermeability of inulin through a cultured brain microvascular endothelial cell monolayer, suggesting an involvement of calmodulin in the regulation of brain microvascular barrier function. The present results demonstrate that DY-9760e ameliorates brain edema formation and suggest that this effect may be mediated in part by the inhibition of enhanced BBB permeability after ischemic insults. Thus, DY-9760e is expected to be a therapeutic drug for treatment of acute stroke patients.
- Published
- 2003
37. Effect of an antihypertensive drug, budralazine, on glucose and lipid metabolism in diabetic SHR
- Author
-
Akira Akashi, Hidemi Masumura, and Yasufumi Shirasaki
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,Diabetes Mellitus, Experimental ,Impaired glucose tolerance ,Rats, Inbred SHR ,Internal medicine ,Diabetes mellitus ,Budralazine ,Animals ,Medicine ,cardiovascular diseases ,Antihypertensive Agents ,Pharmacology ,Triamterene ,business.industry ,Furosemide ,Rats, Inbred Strains ,Lipid metabolism ,Hydralazine ,musculoskeletal system ,Streptozotocin ,medicine.disease ,Lipids ,Rats ,Diabetes Mellitus, Type 1 ,Blood pressure ,Endocrinology ,Diabetes Mellitus, Type 2 ,Biochemistry ,Hypertension ,cardiovascular system ,Female ,business ,circulatory and respiratory physiology ,medicine.drug - Abstract
Budralazine was evaluated for its effects on glucose and lipid metabolism in diabetic SHR. SHR treated with 10% sucrose solution as drinking water for 3 months exhibited an impaired glucose tolerance with higher serum insulin levels and a reduction of sigma delta IRI/sigma delta BS. This model was, therefore, considered to resemble hypertensive patients with non-insulin-dependent diabetes (NIDD). Streptozotocin (30 mg/kg, i.v.)-treated SHR had a glucose intolerance with lower serum insulin levels and a reduction of sigma delta IRI/sigma delta BS, suggesting a similarity to hypertensive states with insulin-dependent diabetes (IDD) in humans. Repeated administration of budralazine (15-60 mg/kg/day, p.o.) had no effect on glucose tolerance, insulin secretion, serum electrolytes and lipid levels in Wistar rats, SHR, IDD-SHR and NIDD-SHR. Budralazine caused a significant decrease in systolic blood pressure in IDD-SHR and NIDD-SHR as well as in SHR. Repeated administration of furosemide (50-100 mg/kg/day, p.o.) resulted in a marked reduction in glucose tolerance, sigma delta IRI/sigma delta BS and serum potassium in Wistar rats. These effects of furosemide were more pronounced in SHR and IDD-SHR (IDD-SHR greater than SHR) and were reduced by either KC1 supplement or administration of triamterene. Thus, furosemide-induced glucose intolerance seems, at least partially, to be attributed to potassium loss which led to decreased insulin secretion. From these results, it is possible that budralazine may be useful for the treatment of hypertensive patients with diabetes.
- Published
- 1986
38. Fluctuation of Aortic Acid Cholesteryl Ester Hydrolase Activity due to Hypertension in the Rat
- Author
-
Yasufumi Shirasaki, Eiichi Hayashi, and Takako Tomita
- Subjects
Biochemistry ,Chemistry ,Acid Cholesteryl Ester Hydrolase - Published
- 1980
39. Aortic cholesterylester hydrolase activity of SHRSP, SHR and WKR, and hemodynamic effect on the enzyme activity [proceedings]
- Author
-
Takako Tomita, Eiichi Hayashi, Akiko Suzuki, and Yasufumi Shirasaki
- Subjects
Carboxylic Ester Hydrolases ,Male ,Aging ,biology ,Chemistry ,Hemodynamics ,Hormone-sensitive lipase ,Sterol Esterase ,Enzyme assay ,Rats ,Cerebrovascular Disorders ,Biochemistry ,Sterol esterase ,Hypertension ,biology.protein ,Animals ,Cardiology and Cardiovascular Medicine ,Antihypertensive Agents - Published
- 1979
40. Effects of phthalazinol (EG 626) and pyridinolcarbamate (Anginin) on lipolytic enzyme activities in rat adipose tissue -in vivo and in vitro
- Author
-
Ikumi Yonekura, Takako Tomita, Eiichi Hayashi, Fujio Numano, and Yasufumi Shirasaki
- Subjects
Male ,medicine.medical_specialty ,Epinephrine ,Lipolysis ,Adipose tissue ,Hormone-sensitive lipase ,Biology ,In Vitro Techniques ,Thromboxane A2 ,chemistry.chemical_compound ,In vivo ,Internal medicine ,medicine ,Animals ,Theophylline ,Phosphodiesterase inhibitor ,Pharmacology ,Pyridinolcarbamate ,Phosphodiesterase ,Sterol Esterase ,Lipids ,Rats ,Pyridazines ,Endocrinology ,chemistry ,Adipose Tissue ,3',5'-Cyclic-AMP Phosphodiesterases ,Phthalazines ,Carbamates ,Carboxylic Ester Hydrolases ,medicine.drug - Abstract
Effects of Phthalazinol (EG 626), a cyclic AMP phosphodiesterase inhibitor, a thromboxane A2 antagonist and an antiatherosclerotic agent was examined regarding lipolytic enzyme activities in rat epididymal adipose tissue. The effect of Pyridinolcarbamate (Anginin) was concomitantly examined. There was a significant decrease in serum triacylglycerol levels in rats given EG 626 (100-500 mg/kg), p.o. for 1-3 weeks. In adipose tissue from EG 626 treated rats, the basal and adrenalin induced lipolysis, and cholesterylester hydrolase activity were markedly enhanced, while the phosphodiesterase activity was decreased. Anginin treatment had no effect either on the serum lipid levels or the cholesterylester hydrolase activity. An elevation in cholesterylester hydrolase activity and lipolysis by EG 626 was observed both in vivo and in vitro. Incubation of the adipose tissue with 0.229 mM of EG 626 or 0.603 mM of theophylline induced a lipolysis equivalent to that seen with 2.7 x 10(-2) mM of adrenalin. These results indicate that EG 626 exerted marked effects on lipolysis and cholesterylester hydrolase activity, probably through inhibition of phosphodiesterase. Possible contributions of the enhanced cholesterylester hydrolase activities to the antiatherogenic effect were discussed.
- Published
- 1980
41. Changes by hypertension and hypercholesterolemia in arterial enzyme activities in the rat
- Author
-
Yasufumi Shirasaki, Takako Tomita, Eiichi Hayashi, Keizo Umegaki, Yoshiharu Takiguchi, and Norihisa Taniguchi
- Subjects
chemistry.chemical_classification ,medicine.medical_specialty ,Endocrinology ,Enzyme ,chemistry ,business.industry ,Internal medicine ,medicine ,Cardiology and Cardiovascular Medicine ,business - Published
- 1982
42. Effect of purine nucleotides on parasympathetic nerves (6) Effect of adenosine and morphine on 14C efflux from the guinea-pig ileum strips incubated with 14C-choline
- Author
-
Yasufumi Shirasaki, Shizuo Yamada, Motokuni Mori, and Eiichi Hayashi
- Subjects
Pharmacology ,chemistry.chemical_classification ,Purine ,Adenosine ,chemistry.chemical_compound ,chemistry ,Morphine ,medicine ,Choline ,Nucleotide ,Efflux ,Guinea pig ileum ,medicine.drug - Published
- 1975
43. Effect of an antihypertensive drug, budralazine, on glucose metabolism in SHR
- Author
-
Akira Akashi, Hidemi Masumura, and Yasufumi Shirasaki
- Subjects
Pharmacology ,medicine.drug_class ,business.industry ,medicine ,Budralazine ,Carbohydrate metabolism ,Antihypertensive drug ,business - Published
- 1985
44. Beneficai effect of cinepazide on cerebral circulation in spontaneously hypertensive rats(SHR) with cerebral lesions
- Author
-
Masanao Ishihara, Seiichi Shibamura, Satoru Tanaka, Yasufumi Shirasaki, Akira Akashi, Hidemasa Ogawa, Makoto Tanaka, and Ikuo Suzuki
- Subjects
Pharmacology ,medicine.medical_specialty ,business.industry ,Cinepazide ,Cerebral circulation ,Blood pressure ,medicine.artery ,Internal medicine ,Concomitant ,Basal ganglia ,Occlusion ,medicine ,Cardiology ,Common carotid artery ,business ,Salt loading - Abstract
Cinepazide(CP) was evaluated for its effect on cerebral circulation of SHR with acute and chronic cerebral lesions using a hydrogen clearance method. In the first experiment, CP(10 mg/ kg i.v.) increased regional cerebral blood flows(rCBFs) in the parietal cortex and basal ganglia, and reversed a decrease in rCBFs resulting from bilateral common carotid artery occlusion for 10 min followed by reperfusion. In the second experiment, in which SHR received 1% NaCl solution for 8 weeks, there was a rapid development of hypertension with a decrease in rCBFs and an acceleration of cerebral lesions, compared to salt-unloaded SHR. Repeated administration of CP(100 and 300 mg/kg p.o.) for 6-9 weeks, initiating at 9 weeks after salt loading, resulted in a dose-related improvement of reduction in rCBFs and of impairment of ocular vessels without remarkable concomitant alternation in systolic blood pressure. These effects were reflected by a low incidence of histo-pathological changes in the cerebral vasculature. These results suggest that improvement of cerebral lesions by CP may be at least in part related to its ability to protect against cerebral hypo -perf us ion.
- Published
- 1983
45. Changes in aortic lysosomal enzyme activities by DOCA-salt and renal hypertension in the rat-comparison with spontaneous hypertension
- Author
-
Eiichi Hayashi, Takako Tomita, Yasufumi Shirasaki, and Yoshiharu Takiguchi
- Subjects
chemistry.chemical_classification ,medicine.medical_specialty ,Enzyme ,Endocrinology ,chemistry ,business.industry ,Internal medicine ,Pathophysiology of hypertension ,medicine ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business ,Doca salt - Published
- 1980
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