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Kume H, Konishi Y, Murayama KS, Kametani F, Araki W. Expression of reticulon 3 in Alzheimer's disease brain. Neuropathol Appl Neurobiol 2009; 35:178-88. [PMID: 19284479 DOI: 10.1111/j.1365-2990.2008.00974.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
AIMS Reticulon 3 (RTN3), a member of the reticulon family of proteins, interacts with the beta-secretase, beta-site amyloid precursor protein-cleaving enzyme 1 (BACE1), and inhibits its activity to produce beta-amyloid protein. The aim of the present study was to clarify the biological role of RTN3 in the brain and its potential involvement in the neuropathology of Alzheimer's disease (AD). METHODS We performed immunohistochemical and biochemical analyses using a specific antibody against RTN3 to investigate the expression and subcellular localization of RTN3 in control and AD brain tissue samples. RESULTS Western blot analysis revealed no significant differences in the RTN3 levels between control and AD brains. Immunohistochemical staining showed that RTN3 immunoreactivity was predominantly localized in pyramidal neurones of the cerebral cortex. The patterns of RTN3 immunostaining were similar in control and AD cerebral cortices, and senile plaques were generally negative for RTN3. Biochemical subcellular fractionation disclosed that RTN3 colocalized with BACE1 in various fractions, including the endoplasmic reticulum and the Golgi apparatus. Double-immunofluorescence staining additionally indicated that RTN3 was localized in both endoplasmic reticulum and Golgi compartments in neurones. CONCLUSIONS These results show that RTN3 is primarily expressed in pyramidal neurones of the human cerebral cortex and that no clear difference of RTN3 immunoreactivity is observable between control and AD brains. Our data also suggest that there is considerable colocalization of RTN3 with BACE1 at a subcellular level.
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Sugiura Y, Konishi Y, Zaima N, Kajihara S, Nakanishi H, Taguchi R, Setou M. Visualization of the cell-selective distribution of PUFA-containing phosphatidylcholines in mouse brain by imaging mass spectrometry. J Lipid Res 2009; 50:1776-88. [PMID: 19417221 DOI: 10.1194/jlr.m900047-jlr200] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies have shown that MALDI-imaging mass spectrometry (IMS) can be used to visualize the distribution of various biomolecules, especially lipids, in the cells and tissues. In this study, we report the cell-selective distribution of PUFA-containing glycerophospholipids (GPLs) in the mouse brain. We established a practical experimental procedure for the IMS of GPLs. We demonstrated that optimization of the composition of the matrix solution and spectrum normalization to the total ion current (TIC) is critical. Using our procedure, we simultaneously differentiated and visualized the localizations of specific molecular species of GPLs in mouse brain sections. The results showed that PUFA-containing phosphatidylcholines (PCs) were distributed in a cell-selective manner: arachidonic acid- and docosahexaenoic acid-containing PCs were seen in the hippocampal neurons and cerebellar Purkinje cells, respectively. Furthermore, these characteristic localizations of PUFA-PCs were formed during neuronal maturation. The phenomenon of brain cell-selective production of specific PUFA-GPLs will help elucidate the potential physiological functions of PUFAs in specific brain regions.
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Konishi Y. Muscle weakness of the quadriceps femoris of patients who underwent anterior cruciate ligament reconstructionremains bilaterally. J Sci Med Sport 2009. [DOI: 10.1016/j.jsams.2008.12.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Otsuka Y, Yamazaki Y, Konishi Y, Kanazawa S, Yamaguchi MK, Spehar B. The perception of illusory transparent surfaces in infancy: Early emergence of sensitivity to static pictorial cues. J Vis 2008; 8:6.1-12. [DOI: 10.1167/8.16.6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Accepted: 09/02/2008] [Indexed: 11/24/2022] Open
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Yang H, Takagi H, Konishi Y, Ageta H, Ikegami K, Yao I, Sato S, Hatanaka K, Inokuchi K, Seog DH, Setou M. Transmembrane and ubiquitin-like domain-containing protein 1 (Tmub1/HOPS) facilitates surface expression of GluR2-containing AMPA receptors. PLoS One 2008; 3:e2809. [PMID: 18665261 PMCID: PMC2474703 DOI: 10.1371/journal.pone.0002809] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 07/05/2008] [Indexed: 12/22/2022] Open
Abstract
Some ubiquitin-like (UBL) domain-containing proteins are known to play roles in receptor trafficking. Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) undergo constitutive cycling between the intracellular compartment and the cell surface in the central nervous system. However, the function of UBL domain-containing proteins in the recycling of the AMPARs to the synaptic surface has not yet been reported. Here, we report that the Transmembrane and ubiquitin-like domain-containing 1 (Tmub1) protein, formerly known as the Hepatocyte Odd Protein Shuttling (HOPS) protein, which is abundantly expressed in the brain and which exists in a synaptosomal membrane fraction, facilitates the recycling of the AMPAR subunit GluR2 to the cell surface. Neurons transfected with Tmub1/HOPS-RNAi plasmids showed a significant reduction in the AMPAR current as compared to their control neurons. Consistently, the synaptic surface expression of GluR2, but not of GluR1, was significantly decreased in the neurons transfected with the Tmub1/HOPS-RNAi and increased in the neurons overexpressing EGFP-Tmub1/HOPS. The altered surface expression of GluR2 was speculated to be due to the altered surface-recycling of the internalized GluR2 in our recycling assay. Eventually, we found that GluR2 and glutamate receptor interacting protein (GRIP) were coimmunoprecipitated by the anti-Tmub1/HOPS antibody from the mouse brain. Taken together, these observations show that the Tmub1/HOPS plays a role in regulating basal synaptic transmission; it contributes to maintain the synaptic surface number of the GluR2-containing AMPARs by facilitating the recycling of GluR2 to the plasma membrane.
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Bastos LFS, Angusti A, Vilaça MC, Merlo LA, Nascimento EB, Rocha LTS, Godin AM, Solano AGR, Jarussophon S, Nunan EA, Konishi Y, Coelho MM. A novel non-antibacterial, non-chelating hydroxypyrazoline derivative of minocycline inhibits nociception and oedema in mice. Br J Pharmacol 2008; 155:714-21. [PMID: 18660827 DOI: 10.1038/bjp.2008.303] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND AND PURPOSE Many in vitro and fewer in vivo studies have shown that tetracyclines present anti-inflammatory activity. We investigated if a novel non-antibacterial, non-chelating hydroxypyrazoline derivative of minocycline, 12S-hydroxy-1,12-pyrazolinominocycline (PMIN), also induced antinociceptive and anti-inflammatory effects. EXPERIMENTAL APPROACH Antibacterial effects against a minocycline-sensitive Staphylococcus aureus strain were evaluated by applying a cylinder-plate agar diffusion technique. Antibacterial effects of diluted serum from mice pre-treated with minocycline or PMIN were also evaluated. Ca2+ binding activity was assessed by spectrophotometry. Formalin-induced nociceptive responses and carrageenan-induced paw oedema were evaluated in mice. The rota-rod apparatus was used to evaluate motor coordination. KEY RESULTS Minocycline, but not PMIN, inhibited bacterial growth. Serum from mice treated with minocycline, but not with PMIN, also induced such an effect. The UV absorption spectrum of solutions of minocycline, but not those of PMIN, was markedly changed in the presence of Ca2+. Minocycline or PMIN inhibited both phases of formalin-induced nociception and carrageenan-induced paw oedema. It is unlikely that antinociception resulted from lack of motor coordination, as tetracycline did not impair the performance of mice on the rotating rod. CONCLUSIONS AND IMPLICATIONS These results indicate that inhibition of nociception and oedema by tetracyclines is neither necessarily linked to antibacterial nor to Ca2+ chelating activities. This study supports the evaluation of the potential usefulness of PMIN in the treatment of painful and inflammatory diseases, as its lack of antibacterial and Ca2+ chelating activities might confer greater safety over conventional tetracyclines.
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Yuan Z, Becker EBE, Merlo P, Yamada T, DiBacco S, Konishi Y, Schaefer EM, Bonni A. Activation of FOXO1 by Cdk1 in cycling cells and postmitotic neurons. Science 2008; 319:1665-8. [PMID: 18356527 DOI: 10.1126/science.1152337] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Activation of cyclin-dependent kinase 1 (Cdk1) has been linked to cell death of postmitotic neurons in brain development and disease. We found that Cdk1 phosphorylated the transcription factor FOXO1 at Ser249 in vitro and in vivo. The phosphorylation of FOXO1 at Ser249 disrupted FOXO1 binding with 14-3-3 proteins and thereby promoted the nuclear accumulation of FOXO1 and stimulated FOXO1-dependent transcription, leading to cell death in neurons. In proliferating cells, Cdk1 induced FOXO1 Ser249 phosphorylation at the G2/M phase of the cell cycle, resulting in FOXO1-dependent expression of the mitotic regulator Polo-like kinase (Plk). These findings define a conserved signaling link between Cdk1 and FOXO1 that may have a key role in diverse biological processes, including the degeneration of postmitotic neurons.
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Yalcin B, Ergungor Z, Konishi Y, Cakmak M, Batur C. Molecular origins of toughening mechanism in uniaxially stretched nylon 6 films with clay nanoparticles. POLYMER 2008. [DOI: 10.1016/j.polymer.2008.01.046] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Iizuka Y, Suzuki M, Yoshimura N, Ohno S, Konishi Y. Paravertebral Arteriovenous Fistulas Presenting Acute Epidural Hematoma Associated with Paraplegia. Neuroradiol J 2008; 21:93-9. [DOI: 10.1177/197140090802100113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2007] [Accepted: 10/14/2007] [Indexed: 11/15/2022] Open
Abstract
We report a unique case of paravertebral arteriovenous fistulas (PVAVF) presenting with acute epidural hematoma produced by dilated venous pouch. The involved level in this patient makes this an extremely rare case. The main feeding artery was the right thyrocervical trunk and the dilated venous pouch was the posterior internal venous plexus around the upper thoracic spine. The etiology of this abnormal arteriovenous communication remains unclear. This case demonstrates that a venous ectasic pouch comprises important etiological angioarchitecture of radiculopathy and myelopathy in PVAVF.
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Iizuka Y, Suzuki M, Komura S, Shimoji K, Tsutsumi Y, Konishi Y, Kaneko K. Hydrovenous Disorder in Vein of Galen Aneurysmal Dilatation: Special Focus on Tonsilar Prolapse. Neuroradiol J 2008; 21:57-64. [DOI: 10.1177/197140090802100107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Accepted: 12/12/2007] [Indexed: 11/17/2022] Open
Abstract
We analyzed five cases of vein of Galen aneurysmal dilatation (VGAD) and 12 cases of vein of Galen aneurysmal malformation (VGAM) using sagittal T1-weighted images. Tonsilar prolapse (TP) was confirmed in three cases, which were all VGAD. Two of these cases were treated by endovascular procedures. In one of these two cases, elevation of TP was observed after intervention. There were no signs of TP in the control group of 12 VGAMs. Venous hypertension interferes with cerebrospinal fluid (CSF) resorption resulting in increased brain fluid. TP frequently develops in high flow AVFs and is reversible if therapeutic intervention is performed by an experienced clinical team when appropriately indicated. We consider that TP in VGAD is mainly the result of cerebellar swelling due to chronic venous hypertension.
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Yamada MK, Konishi Y, Kakinoki B, Ikegami K, Setou M. Enhancement of Trk Signaling Pathways by the Cholestane Amide Conjugate MCC-257. J Pharmacol Sci 2008; 108:131-4. [DOI: 10.1254/jphs.08109sc] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Konishi Y, Tsukiyama T, Tachimi T, Saitoh N, Nomura T, Nagamine S. Microbial deposition of gold nanoparticles by the metal-reducing bacterium Shewanella algae. Electrochim Acta 2007. [DOI: 10.1016/j.electacta.2007.02.073 10.1016/j.electacta.2007.02.073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cho SJ, Roman G, Yeboah F, Konishi Y. The road to advanced glycation end products: a mechanistic perspective. Curr Med Chem 2007; 14:1653-71. [PMID: 17584071 DOI: 10.2174/092986707780830989] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Protein glycation is a slow natural process involving the chemical modification of the reactive amino and guanidine functions in amino acids by sugars and carbohydrates-derived reactive carbonyls. Its deleterious consequences are obvious in the case of long-lived proteins in aged people and are exacerbated by the high blood concentration of sugars in diabetic patients. The non-enzymatic glycation of proteins occurs through a wide range of concurrent processes comprising condensation, rearrangement, fragmentation, and oxidation reactions. Using a few well established intermediates such as Schiff base, Amadori product and reactive a-dicarbonyls as milestones and the results of in vitro glycation investigations, an overall detailed mechanistic analysis of protein glycation is presented for the first time. The pathways leading to several advanced glycation end products (AGEs) such as (carboxymethyl)lysine, pentosidine, and glucosepane are outlined, whereas other AGEs useful as potential biomarkers of glycation are only briefly mentioned. The current stage of the development of glycation inhibitors has been reviewed with an emphasis on their mechanism of action.
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Konishi Y, Sato H, Fujimoto T, Tanaka H, Takahashi O, Tanaka T. A case of primary uterine angiosarcoma: magnetic resonance imaging and computed tomography findings. Int J Gynecol Cancer 2007; 17:280-4. [PMID: 17291268 DOI: 10.1111/j.1525-1438.2007.00800.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Primary uterine angiosarcoma is exceedingly rare and has a poor prognosis. Moreover, the radiologic findings of this disease have not been previously documented. We present a case of a 62-year-old woman with primary uterine angiosarcoma who underwent abdominal hysterectomy and bilateral salpingo-oophorectomy. Histologically, interlacing vascular spaces were lined by endothelial cells showing nuclear pleomorphism and mitotic activity. Immunohistochemical staining was positive for the endothelial cell markers CD31, CD34, and Factor VIII, supporting the diagnosis of primary uterine angiosarcoma. Magnetic resonance imaging (MRI) revealed a heterogeneous mass with high and low signal intensity (T2 weighted) in the uterus and an intense contrast-enhanced anterior area within the mass (gadolinium enhanced, T1 weighted). The lesion was also enhanced on computed tomography (CT). Radiologically, the most helpful sign in the characterization of uterine angiosarcoma is marked heterogeneity on T2-weighted MRI with focal areas of high signal intensity, known as the "cauliflower-like appearance." In addition, findings of a strongly enhanced lesion on gadolinium-enhanced T1-weighted MRI and contrast-enhanced CT also support the diagnosis of angiosarcoma.
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Konishi Y, Ikeda K, Nishino A, Sunaga M, Aihara Y, Fukubayashi T. Relationship between quadriceps femoris muscle volume and muscle torque after anterior cruciate ligament repair. Scand J Med Sci Sports 2007; 17:656-61. [PMID: 17331086 DOI: 10.1111/j.1600-0838.2006.00619.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study was performed to obtain evidence regarding bilateral hindrance of motor unit (MU) recruitment in the quadriceps femoris (QF) of patients with anterior cruciate ligament (ACL) reconstruction. The subjects included 70 patients who underwent ACL reconstruction and 35 healthy subjects. To identify the muscle torque per unit volume (MTPUV), the peak torque of each velocity of isokinetic performance was divided by muscle volume of the QF measured by a series of cross-sectional images obtained by magnetic resonance imaging scans. Tests revealed that the mean MTPUV of the uninjured (0.113+/-0.03 N m/cm3 at 60 degrees /s, 0.081+/-0.02 N m/cm3 at 180 degrees /s) and injured sides (0.109+/-0.03 N m/cm3 at 60 degrees /s, 0.079+/-0.023 N m/cm3 at 180 degrees /s) were significantly lower than those of the control group (0.144+/-0.05 N m/cm3 at 60 degrees /s, 0.096+/-0.04 N m/cm3 at 180 degrees /s). Previous studies suggested that MU recruitment in the QF of patients with ACL injury was hindered bilaterally. However, the design of their studies could not provide evidence of bilateral hindrance of MU recruitment in the QF. The results of the present study demonstrated that the MTPUV of both injured and uninjured sides of patients were significantly lower than those of the control group.
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Bend J, Bolger M, Knaap AGAC, Kuznesof PM, Larsen JC, Mattia A, Meylan I, Pitt JI, Resnik S, Schlatter J, Vavasour E, Rao MV, Verger P, Walker R, Wallin H, Whitehouse B, Abbott PJ, Adegoke G, Baan R, Baines J, Barlow S, Benford D, Bruno A, Charrondiere R, Chen J, Choi M, DiNovi M, Fisher CE, Iseki N, Kawamura Y, Konishi Y, Lawrie S, Leblanc JC, Leclercq C, Lee HM, Moy G, Munro IC, Nishikawa A, Olempska-Beer Z, de Peuter G, Pronk MEJ, Renwick AG, Sheffer M, Sipes IG, Tritscher A, Soares LV, Wennberg A, Williams GM. Evaluation of certain food additives and contaminants. WORLD HEALTH ORGANIZATION TECHNICAL REPORT SERIES 2007:1-225, back cover. [PMID: 18551832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The Committee also evaluated the risk posed by two food contaminants, with the aim of advising on risk management options for the purpose of public health protection. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular flavouring agents) and contaminants. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (acidified sodium chlorite, asparaginase from Aspergillus oryzae expressed in Aspergillus oryzae, carrageenan and processed Eucheuma seaweed, cyclotetraglucose and cyclotetraglucose syrup, isoamylase from Pseudomonas amyloderamosa, magnesium sulfate, phospholipase A1 from Fusarium venenatum expressed in Aspergillus oryzae, sodium iron(III) ethylenediaminetetraacetic acid (EDTA) and steviol glycosides); eight groups of related flavouring agents (linear and branched-chain aliphatic, unsaturated, unconjugated alcohols, aldehydes, acids and related esters; aliphatic acyclic and alicyclic terpenoid tertiary alcohols and structurally related substances; simple aliphatic and aromatic sulfides and thiols; aliphatic acyclic dials, trials and related substances; aliphatic acetals; sulfur-containing heterocyclic compounds; aliphatic and aromatic amines and amides; and aliphatic alicyclic linear alpha, beta -unsaturated di- and trienals and related alcohols, acids and esters); and two food contaminants (aflatoxin and ochratoxin A). Specifications for the following food additives were revised: maltol and ethyl maltol, nisin preparation, pectins, polyvinyl alcohol, and sucrose esters of fatty acids. Specifications for the following flavouring agents were revised: maltol and ethyl maltol, maltyl isobutyrate, 3-acetyl-2,5-dimethylfuran and 2,4,5-trimethyl-delta-oxazoline (Nos 1482, 1506 and 1559), and monomenthyl glutarate (No. 1414), as well as the method of assay for the sodium salts of certain flavouring agents. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives and contaminants considered.
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Konishi Y, Setou M. Neural activity modifies microtubules by tubulin polyglutamylation. Neurosci Res 2007. [DOI: 10.1016/j.neures.2007.06.1392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Konishi Y. fÁ loop dysfunction in the quadriceps femoris of patients who underwent ACL reconstruction remains in the QF muscle on the uninjured side. J Sci Med Sport 2006. [DOI: 10.1016/j.jsams.2006.12.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kluczyk A, Kiyota T, Lazar C, Popek T, Roman G, Konishi Y. Drug evolution concept in drug design: 2. Chimera method. Med Chem 2006; 2:175-89. [PMID: 16787366 DOI: 10.2174/157340606776056214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The drug evolution method represents a novel approach towards efficient rational drug design by implementing the drug evolution concept to the creation and development of general chemical libraries with the purpose of allowing the identification of drug candidates with improved odds and lesser costs than the traditional drug design strategies. As another example of successful translation of the biological evolution into chemical evolution, the chimera method comprises the grafting of selected building blocks, identified through a basic search within a drug library, onto the same substitution sites on a rationally chosen scaffold. The method allows the creation of a library containing both drugs and prospective drug candidates without any priorly required knowledge on the pursued disease or molecular target. Two libraries having scaffolds derived from para-aminobenzoic acid and salicylic acid have exemplified the application of the chimera method. The validation of the method has been achieved through the high number of recognized drugs within the library, which exhibit in the same time a wide variety of therapeutic activities and interact with a broad spectrum of molecular targets. The drug-enriched chimera libraries are expected to provide a highly efficient access to novel drug candidates whose unspecified therapeutic effects should be further revealed through high-throughput screening.
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Konishi Y, Ikeda K, Iwakura Y, Kawakami K. Six1 and Six4 promote survival of sensory neurons during early trigeminal gangliogenesis. Brain Res 2006; 1116:93-102. [PMID: 16938278 DOI: 10.1016/j.brainres.2006.07.103] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Revised: 07/16/2006] [Accepted: 07/28/2006] [Indexed: 10/24/2022]
Abstract
Survival of sensory neurons is tightly regulated in cell-type and developmental-stage-specific manners. The transcriptional regulatory mechanisms underlying this regulation remain to be elucidated. In the present study, we investigated the role of Six1 and Six4 in the development of trigeminal ganglia. Abundant expression of Six1 and Six4 was noted in sensory neurons during early trigeminal gangliogenesis. Loss of both Six1 and Six4 in mice caused severe defects in the trigeminal ganglia, wherein massive apoptosis accompanied by activation of caspase-3 was observed at early but not late stages of gangliogenesis. In Six1(-/-)Six4(-/-) mice, trigeminal sensory neurons were generated, but showed reduced expression of Bcl-x compared with the wild-type mice. Accordingly, neurons from the deficient mice could not survive in culture even in the presence of neurotrophins. Our results suggest a cell-intrinsic role of Six1 and Six4 in the survival of early-generated trigeminal sensory neurons.
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Okumura M, Masada M, Yoshida Y, Shintaku H, Hosoi M, Okada N, Konishi Y, Morikawa T, Miura K, Imanishi M. Decrease in tetrahydrobiopterin as a possible cause of nephropathy in type II diabetic rats. Kidney Int 2006; 70:471-6. [PMID: 16775605 DOI: 10.1038/sj.ki.5000431] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A decrease in renal synthesis of nitric oxide (NO) in the progression of diabetic nephropathy has been documented. As (6R)-5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor of NO synthase, we investigated whether BH4 deficiency is involved in the pathogenesis of nephropathy. Ten-week-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats were used as a type II diabetic model, and Long-Evans Tokushima Otsuka (LETO) rats as the healthy controls. OLETF rats were orally treated with BH4 (10 mg/kg daily) or with water from 10 to 61 weeks of age. In another experiment, OLETF rats were treated orally with a calcium channel blocker, benidipine (5 mg/kg daily), or with 0.3% carboxymethyl cellulose (nontreated) from 10 to 52 weeks of age. Proteinuria was observed periodically, and at the end of the study, BH4 level and GTP cyclohydrolase I (GTPCH) activity in the kidney were measured. Proteinuria was observed at 13 weeks of age in the OLETF rats, and deteriorated until 61 weeks of age. Supplemental BH4 reduced the proteinuria. At 52 weeks of age, GTPCH activity and the BH4 level were decreased in the plasma and kidneys of OLETF rats, whereas they were significantly higher in the benidipine group than in the nontreated group. Proteinuria was milder in the benidipine group than in the nontreated group, without a concomitant decrease in blood pressure. Histologically observed glomerulosclerosis was mild in the BH4 and benidipine groups. In type II diabetic rats, renal BH4 is considered to play a crucial role in the pathogenesis of diabetic nephropathy. Benidipine was found to preserve BH4 levels, suggesting therapeutic renoprotective effects.
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Konishi Y, Aihara Y, Sakai M, Ogawa G, Fukubayashi T. Gamma loop dysfunction in the quadriceps femoris of patients who underwent anterior cruciate ligament reconstruction remains bilaterally. Scand J Med Sci Sports 2006; 17:393-9. [PMID: 16805784 DOI: 10.1111/j.1600-0838.2006.00573.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Purpose of this study was to investigate the effects of anterior cruciate ligament (ACL) repair on the gamma loop of the bilateral quadriceps femoris (QF). Maximal voluntary contraction (MVC) of knee extension and integrated electromyogram (I-EMG) of vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) were examined in uninjured and injured limbs of 18 patients and 10 normal subjects, before and after 20-min vibration applied to the QF. Mean percentage changes were calculated as: (pre-vibration value-post-vibration value)/pre-vibration value x 100. Patients were divided into two groups: short-term-group (tested </=12 months after ACL repair, n=8), long-term-group (tested >/=18 months after ACL repair, n=10). Mean percentage changes of the four groups were compared with those of controls. Results indicated that changes of MVC and I-EMG on the uninjured and injured sides in short-term-group in response to vibration were significantly different from those of controls. There were no significant differences between uninjured sides in long-term and control groups. MVC and I-EMG of VM and RF of injured side in patients in the long-term-group in response to vibration were not different from those of controls. From these results, we concluded that this abnormality of the gamma loop in both injured and uninjured sides did not recover despite ACL reconstruction. However, the abnormality in uninjured side might recover >/=18 months after repair.
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Stegmüller J, Konishi Y, Huynh MA, Yuan Z, Dibacco S, Bonni A. Cell-intrinsic regulation of axonal morphogenesis by the Cdh1-APC target SnoN. Neuron 2006; 50:389-400. [PMID: 16675394 DOI: 10.1016/j.neuron.2006.03.034] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Revised: 09/12/2005] [Accepted: 03/27/2006] [Indexed: 11/22/2022]
Abstract
Axonal growth is fundamental to the establishment of neuronal connectivity in the brain. However, the cell-intrinsic mechanisms that govern axonal morphogenesis remain to be elucidated. The ubiquitin ligase Cdh1-anaphase-promoting complex (Cdh1-APC) suppresses the growth of axons in postmitotic neurons. Here, we report that Cdh1-APC operates in the nucleus to inhibit axonal growth. We also identify the transcriptional corepressor SnoN as a key target of neuronal Cdh1-APC that promotes axonal growth. Cdh1 forms a physical complex with SnoN and stimulates the ubiquitin-dependent proteasomal degradation of SnoN in neurons. Knockdown of SnoN in neurons significantly reduces axonal growth and suppresses Cdh1 RNAi enhancement of axonal growth. In addition, SnoN knockdown in vivo suggests an essential function for SnoN in the development of granule neuron parallel fibers in the cerebellar cortex. These findings define Cdh1-APC and SnoN as components of a cell-intrinsic pathway that orchestrates axonal morphogenesis in a transcription-dependent manner in the mammalian brain.
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Sato E, Konishi Y, Shimada A, Komatsubara K, Yazaki H, Fujitsuka M, Shiokawa Y. Applications and Roles of Coil Embolization and/or Clipping in the Treatment of Cerebral Aneurysm. Interv Neuroradiol 2006; 12:77-85. [PMID: 20569607 DOI: 10.1177/15910199060120s111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Accepted: 12/15/2005] [Indexed: 11/17/2022] Open
Abstract
SUMMARY We retrospectively analysed to demonstrate the selection of the treatment modality and its efficacy in our department. Subjects of the present study comprised patients in whom coil embolization was abandoned due to such reasons as broad neck, whom coil embolization was performed for residual aneurysm following incomplete clipping or recurrent cerebral aneurysm, whom coil embolization was performed after coil compaction, whom coil embolization and clipping were performed for the treatment of multiple cerebral aneurysms. In the treatment of cerebral aneurysm, selecting proper techniques by considering the characteristics of clipping and coil embolization is desirable. In other words, strategizing therapy by taking advantages of the merits of clipping and coil embolization is important.
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Uehara Y, Agematsu K, Kikuchi K, Matsuzaki S, Imai S, Takamoto M, Sugane K, Sugiura T, Konishi Y, Yoshino N, Takeuchi S, Seo H, Kuramoto S, Sugai M. Secretory IgA, salivary peroxidase, and catalase-mediated microbicidal activity during hydrogen peroxide catabolism in viridans streptococci: pathogen coaggregation. J Infect Dis 2006; 194:98-107. [PMID: 16741888 DOI: 10.1086/504439] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Accepted: 01/26/2006] [Indexed: 11/03/2022] Open
Abstract
Viridans streptococci can kill methicillin-resistant Staphylococcus aureus (MRSA) through the production of hydrogen peroxide (H2O2). However, several hundred viridans streptococci cells are necessary to kill 1 cfu of MRSA. We analyzed the potency of bactericidal and fungicidal effector molecules induced by catabolism of H2O2 in the oral cavity. Secretory IgA (SIgA) and an unidentified salivary component bound Streptococcus sanguinis, a viridans streprococcus, and MRSA into coaggregates. In these coaggregates, salivary peroxidase and the MRSA catalase produced singlet molecular oxygen (1O2) from H2O2 produced by viridans streptococci. SIgA converted 1O2 into ozone, which has potent bactericidal and fungicidal activity. We calculated that <10 cfu of Streptococcus sanguinis were necessary to kill 1 cfu of MRSA in the coaggregate. SIgA, Aspergillus niger catalase, and H2O2 in saliva killed Candida albicans, which is highly resistant to reagent H2O2. Together with indigenous bacteria and innate immunity, SIgA potentially constitutes a novel system that may sustain oral homeostasis.
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