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TAGA Atsushi


FacultyDepartment of Pharmacy / Graduate School of Medicine / Pharmaceutical Research and Technology Institute
Commentator Guide
Last Updated :2020/08/10

Education and Career


  •  - 1992 , Kindai University, Graduate School of Pharmacy
  •  - 1990 , Kindai University, Faculty of Pharmacy
  •  - 1992 , Kinki University, Graduate School, Division of Pharmaceutical Sciences
  •  - 1990 , Kinki University, Faculty of Pharmaceutical Science

Research Activities

Research Areas

  • Life sciences, Pharmaceuticals - analytical and physicochemistry

Research Interests

  • Analytical Chemistry

Published Papers

  • Separation of Synephrine Enantiomers in Citrus Fruits by a Reversed Phase HPLC after Chiral Precolumn Derivatization., Tanaka S, Sekiguchi M, Yamamoto A, Aizawa SI, Sato K, Taga A, Terashima H, Ishihara Y, Kodama S, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, 35(4), 407 - 412, Apr. 2019 , Refereed
  • Dark-colored maple syrup treatment induces S-phase cell cycle arrest via reduced proliferating cell nuclear antigen expression in colorectal cancer cells., Yamamoto T, Nishita T, Taga A, Oncology letters, Oncology letters, 17(3), 2713 - 2720, Mar. 2019 , Refereed
  • Collagen peptides from soft‑shelled turtle induce calpain‑1 expression and regulate inflammatory cytokine expression in HaCaT human skin keratinocytes., Yamamoto T, Nakanishi S, Mitamura K, Taga A, International journal of molecular medicine, International journal of molecular medicine, 42(2), 1168 - 1180, Aug. 2018 , Refereed
  • Chiral separation of isoxanthohumol and 8-prenylnaringenin in beer, hop pellets and hops by HPLC with chiral columns., Moriya H, Tanaka S, Iida Y, Kitagawa S, Aizawa SI, Taga A, Terashima H, Yamamoto A, Kodama S, Biomedical chromatography : BMC, Biomedical chromatography : BMC, 32(10), e4289, May 2018 , Refereed
  • Instillation of Sericin Enhances Corneal Wound Healing through the ERK Pathway in Rat Debrided Corneal Epithelium., Nagai N, Fukuoka Y, Ishii M, Otake H, Yamamoto T, Taga A, Okamoto N, Shimomura Y, International journal of molecular sciences, International journal of molecular sciences, 19(4), Apr. 2018 , Refereed
  • Proteomic profile of the lens in a streptozotocin-induced diabetic rat model using shotgun proteomics., Nagai N, Yamamoto T, Mitamura K, Taga A, Biomedical reports, Biomedical reports, 7(5), 445 - 450, Nov. 2017 , Refereed
  • Shotgun label-free proteomic analysis for identification of proteins in HaCaT human skin keratinocytes regulated by the administration of collagen from soft-shelled turtle., Yamamoto T, Nakanishi S, Mitamura K, Taga A, Journal of biomedical materials research. Part B, Applied biomaterials, Journal of biomedical materials research. Part B, Applied biomaterials, 106(6), 2403 - 2413, Nov. 2017 , Refereed
  • Effect of dark-colored maple syrup on cell proliferation of human gastrointestinal cancer cell., Yamamoto T, Sato K, Kubota Y, Mitamura K, Taga A, Biomedical reports, Biomedical reports, 7(1), 6 - 10, Jul. 2017 , Refereed
  • Identification of aldolase A as a potential diagnostic biomarker for colorectal cancer based on proteomic analysis using formalin-fixed paraffin-embedded tissue., Yamamoto T, Kudo M, Peng WX, Takata H, Takakura H, Teduka K, Fujii T, Mitamura K, Taga A, Uchida E, Naito Z, Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine, Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine, 37(10), 1 - 12, Oct. 2016 , Refereed
  • Simultaneous Determination of Trigonelline, Caffeine, Chlorogenic Acid and Their Related Compounds in Instant Coffee Samples by HPLC Using an Acidic Mobile Phase Containing Octanesulfonate., Arai K, Terashima H, Aizawa S, Taga A, Yamamoto A, Tsutsumiuchi K, Kodama S, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, 31(8), 831 - 835, 2015 , Refereed
  • Simultaneous enantioseparation of monosaccharides derivatized with L-tryptophan by reversed phase HPLC., Akabane M, Yamamoto A, Aizawa S, Taga A, Kodama S, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry, 30(7), 739 - 743, 2014 , Refereed
  • Determination of α-hydroxy acids and their enantiomers in fruit juices by ligand exchange CE with a dual central metal ion system., Kodama S, Aizawa S, Taga A, Yamamoto A, Honda Y, Suzuki K, Kemmei T, Hayakawa K, Electrophoresis, Electrophoresis, 34(9/10), 1327 - 1333, May 2013 , Refereed
  • Enantioseparation of alpha-hydroxy acids by chiral ligand exchange CE with a dual central metal ion system, Shuji Kodama, Atsushi Yamamoto, Sen-ichi Aizawa, Yoshitaka Honda, Kentaro Suzuki, Tomoko Kemmei, Atsushi Taga, ELECTROPHORESIS, ELECTROPHORESIS, 33(18), 2920 - 2924, Sep. 2012 , Refereed
    Summary:Using two kinds of central metal ions in a background electrolyte, ligand exchange CE was investigated for the simultaneous enantioseparation of dl-malic, dl-tartaric, and dl-isocitric acids. Ligand exchange CE with 100 mM d-quinic acid as a chiral selector ligand and 10 mM Cu(II) ion as a central metal ion could enantioseparate dl-tartaric acid but not dl-malic acid or dl-isocitric acid. A dual central metal ion system containing 0.5 mM Al(III) ion in addition to 10 mM Cu(II) ion in the background electrolyte enabled the simultaneous enantioseparation of the three a-hydroxy acids. These results suggest that the use of a dual central metal ion system can be useful for enantioseparation by ligand exchange CE.
  • Direct enantioseparation of lipoic acid in dietary supplements by capillary electrophoresis using trimethyl-beta-cyclodextrin as a chiral selector, Shuji Kodama, Atsushi Taga, Sen-ich Aizawa, Tomoko Kemmei, Yoshitaka Honda, Kentaro Suzuki, Atsushi Yamamoto, ELECTROPHORESIS, ELECTROPHORESIS, 33(15), 2441 - 2445, Aug. 2012 , Refereed
    Summary:Lipoic acid, an antioxidant, naturally occurs as the (R)-enantiomer, while synthetic lipoic acid is racemic. It is thus of interest to know the (R)-enantiomer content of lipoic acid supplements. Here, we used capillary electrophoresis to directly enantioseparate lipoic acid in dietary supplements by using a sulfonated capillary with an effective voltage of +18 kV and direct detection at 200 nm. Factors affecting migration time and resolution of lipoic acid were investigated. The optimum background electrolyte was found to be 100 mM phosphate buffer (pH 7.0) containing 8 mM trimethyl-beta-cyclodextrin as a chiral selector at 20 degrees C. Under the proposed conditions, direct chiral resolution of lipoic acid in dietary supplements was conducted successfully.
  • Evaluation of brilliance and visibility of fluorescence and chemiluminescence solution for training of preparing injections., Ishiwata S, Taga A, Sano H, Kobayashi M, Nomiyama J, Harada S, Kita A, Takada M, Sugiura R, Yakugaku Zasshi, Yakugaku Zasshi, 131(9), 1361 - 1367, Jun. 2011 , Refereed
  • Mangiferin Induces Apoptosis by Suppressing Bcl-xL and XIAP Expressions and Nuclear Entry of NF-kappa B in HL-60 Cells, Kaori Shoji, Masanobu Tsubaki, Yuzuru Yamazoe, Takao Satou, Tatsuki Itoh, Yasuhiro Kidera, Yoshihiro Tanimori, Masashi Yanae, Hideaki Matsuda, Atsushi Taga, Haruyuki Nakamura, Shozo Nishida, ARCHIVES OF PHARMACAL RESEARCH, ARCHIVES OF PHARMACAL RESEARCH, 34(3), 469 - 475, Mar. 2011 , Refereed
    Summary:Mangiferin, 1,3,6,7-tetrahydroxyxanthone-C2-beta-D-glucoside (C-glucosylxanthone), is a xanthone derivative that is widely distributed in higher plants. Recently, mangiferin was found to exhibit potential antitumor effects. However, the molecular mechanisms of this effect have not been elucidated. In the present study, we attempt to clarify the mechanism of mangiferin-induced apoptosis in the human acute myeloid leukemia cell line HL-60; mangiferin was found to induce apoptosis. We also observed a concurrent increase in caspase-3 activity and DNA fragmentation. Furthermore, on examining the survival signals expressed during apoptotic induction, we observed that mangiferin caused a remarkable decrease in the nuclear entry of NF-kappa B p65. However, there were no changes in the expression of other survival signals, such as extracellular signal-regulated kinase 1/2, protein kinase B, and p38 mitogen-activated protein kinase. In addition, mangiferin suppressed the expressions of Bcl-xL and XIAP; however, we did not note any changes in the levels of Bcl-2, Bax, and Bim. These results indicate that mangiferin induces apoptosis by suppressing NF-kappa B activation and expressions of Bcl-xL and XAIP. These findings suggest that mangiferin may be useful as an anticancer agent and can be used in combination therapy with other anticancer drugs for the treatment of acute myeloid leukemia.
  • Role of the RNA-binding protein Nrd1 and Pmk1 mitogen-activated protein kinase in the regulation of myosin mRNA stability in fission yeast., Satoh R, Morita T, Takada H, Kita A, Ishiwata S, Doi A, Hagihara K, Taga A, Matsumura Y, Tohda H, Sugiura R, Molecular biology of the cell, Molecular biology of the cell, 20(9), 2473 - 2485, May 2009 , Refereed
  • Affinity capillary electrophoresis of oligosaccharides., Taga A, Honda S, Methods in molecular biology (Clifton, N.J.), Methods in molecular biology (Clifton, N.J.), 213, 121 - 130, 2003 , Refereed
  • Determination of association constant of carbohydrate-protein interaction., Taga A, Honda S, Methods in molecular biology (Clifton, N.J.), Methods in molecular biology (Clifton, N.J.), 213, 275 - 284, 2003 , Refereed
  • Studies of carbohydrate-protein interaction by capillary electrophoresis., Honda S, Taga A, Methods in enzymology, Methods in enzymology, 362, 434 - 454, 2003 , Refereed
  • A Proteomic Approach for Understanding the Mechanisms of Delayed Corneal Wound Healing in Diabetic Keratopathy Using Diabetic Model Rat, Tetsushi Yamamoto, Hiroko Otake, Noriko Hiramatsu, Naoki Yamamoto, Atsushi Taga, Noriaki Nagai, INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, 19(11), Nov. 2018 , Refereed
    Summary:Diabetes mellitus is a widespread metabolic disorder, and long-term hyperglycemia in diabetics leads to diabetic keratopathy. In the present study, we used a shotgun liquid chromatography/mass spectrometry-based global proteomic approach using the cornea of streptozotocin-induced diabetic (STZ) rats to examine the mechanisms of delayed corneal wound healing in diabetic keratopathy. Applying a label-free quantitation method based on spectral counting, we identified 188 proteins that showed expression changes of >2.0-fold in the cornea of STZ rats. In particular, the level of lumican expression in the cornea of STZ rats was higher than that of the normal rats. In the cornea of the normal rat, the expression level of lumican was elevated during the wound healing process, and it returned to the same expression level as before cornea injury after the wound was healed completely. On the other hand, a high expression level of lumican in the cornea of STZ rats was still maintained even after the wound was healed completely. In addition, adhesion deficiency in corneal basal cells and Bowman's membrane was observed in the STZ rat. Thus, abnormally overexpressed lumican may lead to adhesion deficiency in the cornea of STZ rats.
  • Simultaneous determination of alcohols including diols and triols by HPLC with ultraviolet detection based on the formation of a copper(II) complex, Sohei Tanaka, Takumi Dohi, Sen-ichi Aizawa, Tomoko Kemmei, Hiroyuki Terashima, Atsushi Taga, Atsushi Yamamoto, Shuji Kodama, JOURNAL OF SEPARATION SCIENCE, JOURNAL OF SEPARATION SCIENCE, 40(21), 4168 - 4175, Nov. 2017 , Refereed
    Summary:We developed a reversed-phase high-performance liquid chromatography method with ultraviolet detection using on-line complexation with Cu(II) ion for analysis of five alcohols including diols and triol (methanol, ethanol, 1,2-propanediol, 1,3-propanediol, and glycerol). The Cu(II) ion concentration in the mobile phase had a great influence on the peak areas of these alcohols, but not on their retention times. Column temperature (25-40 degrees C) and pH of the mobile phase did not affect the separation of analytes. The optimum separation conditions were determined as 5 mM CuSO4, 3 mM H2SO4, and 3 mM NaOH at 30 degrees C. The ratio of the peak areas for three alcohols (methanol, 1,2-propanediol, and glycerol) was in good agreement with that calculated from the obtained stability constants, molar absorption coefficients for the 1:1 Cu(II) complexes with the three alcohols, and the injected molar quantities. This fact strongly suggests that the observed high-performance liquid chromatography signals resulted from formation of the 1:1 Cu(II)-alcohol complexes. Using the proposed method, these five alcohols in spirit, liquid for electronic cigarette, mouthwash, and nail enamel remover samples were successfully analyzed with only a simple pretreatment.
  • HPLC Separation of Sulforaphane Enantiomers in Broccoli and Its Sprouts by Transformation into Diastereoisomers Using Derivatization with (S)-Leucine, Makiko Okada, Atsushi Yamamoto, Sen-ichi Aizawa, Atsushi Taga, Hiroyuki Terashima, Shuji Kodama, JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 65(1), 244 - 250, Jan. 2017 , Refereed
    Summary:Racemic sulforaphane, which was derivatized with (S)-leucine (L-leucine), was resolved by reversed phase HPLC with UV detection. The optimum mobile phase conditions were found to be 10 mM citric acid (pH 2.8) containing 22% methanol at 35 degrees C using detection at 254 nm. Sulforaphane enantiomers in florets and stems of five brands of broccoli and leaves and stems of three brands of broccoli sprouts were analyzed by the proposed HPLC method. Both sulforaphane enantiomers were detected in all of the samples. The S/R ratios of sulforaphane in broccoli samples were 1.5-2.6/97.4-98.5% for florets and 5.0-12.1/87.9-95.0% for stems. The S/R ratios in broccoli sprout samples were higher than those in broccoli samples and were found to be 8.3-19.7/80.3-91.7% for leaves and 37.0-41.8/58.2-63.0% for stems. (S)-Sulforaphane detected in the broccoli and its sprout samples was positively identified by separately using an HPLC with a chiral column (Chiralpak AD-RH) and mass spectrometry.
  • Optimization of Method to Extract Collagen from "Emperor" Tissue of Soft-shelled Turtles, Tetsushi Yamamoto, Kentaro Uemura, Yuki Sawashi, Kuniko Mitamura, Atsushi Taga, JOURNAL OF OLEO SCIENCE, JOURNAL OF OLEO SCIENCE, 65(2), 169 - 175, Feb. 2016 , Refereed
    Summary:Soft-shelled turtles (Pelodiscus sinensis) are widely distributed in some Asian countries, and parts of this turtle contain abundant collagen. In this study, we optimized a method for extracting collagen from the soft-shelled turtle. We used three types of solvent and four extraction conditions to determine an effective collagen extraction method, which was extraction at 37 degrees C with acetic acid after hydrochloric acid pretreatment. Next, we extracted collagen from three regions in the soft-shelled turtle: muscle, skin, and an area of soft tissue in the periphery of the turtle shell known in Japan and China as the "emperor." We determined that emperor tissue yielded the highest concentration and purity of collagen. We then optimized the pretreatment method for extraction from emperor tissue by using formic acid instead of hydrochloric acid, and the amount of extracted collagen increased by approximately 1.3-fold. Finally, we identified the optimal solvent out of four types of organic acid for collagen extraction from emperor tissue; the amount of extracted collagen from emperor tissue increased approximately 3-fold when citric acid was used as the extraction solvent instead of acetic acid. Emperor tissue can regenerate; thus, it is possible to obtain collagen from the emperor repeatedly without killing the turtle. Our findings suggest that the emperor tissue of soft-shelled turtles may be a good source of collagen for pharmaceutical and cosmetic applications.
  • Peripheral HMGB1-induced hyperalgesia in mice: Redox state-dependent distinct roles of RAGE and TLR4, Daichi Yamasoba, Maho Tsubota, Risa Domoto, Fumiko Sekiguchi, Hiroyuki Nishikawa, Keyue Liu, Masahiro Nishibori, Hiroyasu Ishikura, Tetsushi Yamamoto, Atsushi Taga, Atsufumi Kawabata, JOURNAL OF PHARMACOLOGICAL SCIENCES, JOURNAL OF PHARMACOLOGICAL SCIENCES, 130(2), 139 - 142, Feb. 2016 , Refereed
    Summary:Nuclear HMGB1 that contains 3 cysteine residues is acetylated and secreted to the extracellular space, promoting inflammation via multiple molecules such as RAGE and TLR4. We thus evaluated and characterized the redox state-dependent effects of peripheral HMGB1 on nociception. Intraplantar ( administration of bovine thymus-derived HMGB1 (bt-HMGB1), all-thiol HMGB1 (at-HMGB1) or disulfide HMGB1 (ds-HMGB1) caused long-lasting mechanical hyperalgesia in mice. The hyperalgesia following bt-HMGB1 or at-HMGB1 was attenuated by RAGE inhibitors, while the ds-HMGB1-induced hyperalgesia was abolished by a TLR4 antagonist. Thus, nociceptive processing by peripheral HMGB1 is considered dependent on its redox states. (C) 2016 Japanese Pharmacological Society. Production and hosting by Elsevier B.V.
  • Surface charge-transfer complex formation of catechol on titanium(IV) oxide and the application to bio-sensing, Yusuke Murata, Hiroshige Hori, Atsushi Taga, Hiroaki Tada, JOURNAL OF COLLOID AND INTERFACE SCIENCE, JOURNAL OF COLLOID AND INTERFACE SCIENCE, 458, 305 - 309, Nov. 2015 , Refereed
    Summary:Adsorption properties of 2-hydroxyphenol (catechol) on TiO2 particles has been studied at 298 K. The adsorption proceeds from the aqueous solution with the Langmuir type behavior. Diffuse reflectance infrared spectra of the catechol-adsorbed TiO2 suggested that catechol is adsorbed on TiO2 solution via the chelation to the surface Ti ions. The adsorption induces a strong absorption in the whole visible region, of which intensity increases with an increase in the adsorption amount. Photoelectrochemical experiments and molecular orbital calculations indicate that the absorption stems from the charge-transfer (CT) transition from the HOMO of catechol to the conduction band of TiO2. Time courses for the adsorption of catechol on mesoporous TiO2 nanocrystalline film-coated glass was traced by measuring the change in the absorbance of the CT band, and analyzed on the basis of the Langmuir model. This study would present a new simple technique for sensing of important biomolecules bearing the catechol moiety. (C) 2015 Published by Elsevier Inc.
  • Simultaneous Enantioseparation of Aldohexoses and Aldopentoses Derivatized With L-Tryptophanamide by Reversed Phase HPLC Using Butylboronic Acid as a Complexation Reagent of Monosaccharides, Mirei Shou, Hiroyuki Terashima, Sen-Ichi Aizawa, Atsushi Taga, Atsushi Yamamoto, Shuji Kodama, CHIRALITY, CHIRALITY, 27(7), 417 - 421, Jul. 2015 , Refereed
    Summary:Three aldohexoses, glucose, galactose, and mannose, and three aldopentoses, arabinose, xylose, and ribose, were derivatized with L-tryptophanamide (L-TrpNH(2)) under alkaline conditions. Using a basic mobile phase (pH9.2), the three aldohexoses or the three aldopentoses were simultaneously enantioseparated, respectively, but all the six monosaccharides could not be simultaneously enantioseparated. A large amount of nonreacted L-TrpNH(2) was detected after the derivatized monosaccharides. In order to widen the separation window, a large portion of nonreacted L-TrpNH(2) could be eliminated by liquid-liquid extraction with ethylacetate, and elution order of the derivatized monosaccharides and nonreacted L-TrpNH(2) was found to be reversed using a neutral mobile phase. All of the six monosaccharides were simultaneously enantioseparated by reversed phase high-performance liquid chromatography (HPLC) using InertSustainSwift C18 column (4.6mm i.d. x 150mm) and a mobile phase containing 180mM phosphate buffer (pH7.6), 1.5mM butylboronic acid, and 5% acetonitrile at 40 degrees C. Nomenclature of D and L for monosaccharides is based on the configurations of the asymmetric C4 center for aldopentoses and C5 center for aldohexoses. It was found that the enantiomer elution order of these six monosaccharides and fucose in the proposed method conformed to be the absolute configuration of the C2 center. Chirality 27:417-421, 2015. (c) 2015 Wiley Periodicals, Inc.
  • Inhibitory effect of maple syrup on the cell growth and invasion of human colorectal cancer cells, Tetsushi Yamamoto, Kentaro Uemura, Kaho Moriyama, Kuniko Mitamura, Atsushi Taga, ONCOLOGY REPORTS, ONCOLOGY REPORTS, 33(4), 1579 - 1584, Apr. 2015 , Refereed
    Summary:Maple syrup is a natural sweetener consumed by individuals of all ages throughout the world. Maple syrup contains not only carbohydrates such as sucrose but also various components such as organic acids, amino acids, vitamins and phenolic compounds. Recent studies have shown that these phenolic compounds in maple syrup may possess various activities such as decreasing the blood glucose level and an anticancer effect. In this study, we examined the effect of three types of maple syrup, classified by color, on the cell proliferation, migration and invasion of colorectal cancer (CRC) cells in order to investigate whether the maple syrup is suitable as a phytomedicine for cancer treatment. CRC cells that were administered maple syrup showed significantly lower growth rates than cells that were administered sucrose. In addition, administration of maple syrup to CRC cells caused inhibition of cell invasion, while there was no effect on cell migration. Administration of maple syrup clearly inhibited AKT phosphorylation, while there was no effect on ERK phosphorylation. These data suggest that maple syrup might inhibit cell proliferation and invasion through suppression of AKT activation and be suitable as a phytomedicine for CRC treatment, with fewer adverse effects than traditional chemotherapy.
  • Changes in Plasma Glucose in Otsuka Long-Evans Tokushima Fatty Rats After Oral Administration of Maple Syrup, Noriaki Nagai, Tetsushi Yamamoto, Wataru Tanabe, Yoshimasa Ito, Satoshi Kurabuchi, Kuniko Mitamura, Atsushi Taga, JOURNAL OF OLEO SCIENCE, JOURNAL OF OLEO SCIENCE, 64(3), 331 - 335, Mar. 2015 , Refereed
    Summary:We investigate whether maple syrup is a suitable sweetener in the management of type 2 diabetes using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The enhancement in plasma glucose (PG) and glucose absorption in the small intestine were lower after the oral administration of maple syrup than after sucrose administration in OLETF rats, and no significant differences were observed in insulin levels. These data suggested that maple syrup might inhibit the absorption of glucose from the small intestine and preventing the enhancement of PG in OLETF rats. Therefore, maple syrup might help in the prevention of type 2 diabetes.
  • Comparison of the Enhancement of Plasma Glucose Levels in Type 2 Diabetes Otsuka Long-Evans Tokushima Fatty Rats by Oral Administration of Sucrose or Maple Syrup, Noriaki Nagai, Yoshimasa Ito, Atsushi Taga, JOURNAL OF OLEO SCIENCE, JOURNAL OF OLEO SCIENCE, 62(9), 737 - 743, Sep. 2013 , Refereed
    Summary:Maple syrup is used as a premium natural sweeter, and is known for being good for human health. In the present study, we investigate whether maple syrup is suitable as a sweetener in the management of type 2 diabetes using Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type 2 diabetes mellitus. OLETF rats develop type 2 diabetes mellitus by 30 weeks of age, and 60-week-old OLETF rats show hyperglycemia and hypoinsulinemia via pancreatic beta-cell dysfunction. The administration of sucrose or maple syrup following an OGT test increased plasma glucose (PG) levels in OLETF rats, but the enhancement in PG following the oral administration of maple syrup was lower than in the case of sucrose administration in both 30- and 60-week-old OLETF rats. Although, the insulin levels in 30-week-old OLETF rats also increased following the oral administration of sucrose or maple syrup, no increase in insulin levels was seen in 60-week-old OLETF rats following the oral administration of either sucrose or maple syrup. No significant differences were observed in insulin levels between sucrose- and maple syrup-administered OLETF rats at either 30 or 60 weeks of age. The present study strongly suggests that the maple syrup may have a lower glycemic index than sucrose, which may help in the prevention of type 2 diabetes.
  • Improvement of Dissolution Test Using Micro-controlled Roller Pump, Noriaki Nagai, Nahoko Konishi, Tadahisa Nitta, Atsushi Taga, Yoshimasa Ito, YAKUGAKU ZASSHI-JOURNAL OF THE PHARMACEUTICAL SOCIETY OF JAPAN, YAKUGAKU ZASSHI-JOURNAL OF THE PHARMACEUTICAL SOCIETY OF JAPAN, 132(11), 1307 - 1316, Nov. 2012 , Refereed
    Summary:The dissolution test is a core performance test in pharmaceutical development and quality control of solid drug products. The conventional HPLC dissolution method (batch-sampling method) involves many steps including the filtration, collection and replenishment of sample solutions. We previously reported a dissolution test that involved microdialysis methods (microdialysis-HPLC method) and allowed many steps to be omitted. However, the recovery rate of theophylline by the microdialysis-HPLC method was lower, and the decrease in the flow rate through the dialysis probe caused variation between each tablet. In this study, we have attempted to improve the dissolution test by using a precise micro-controlled roller pump and microfiltering probe (microfiltering-HPLC method). Sustained release preparations of Theodur (R) (100 mg) were used, and the test solutions used were water, buffer at pH 1.2 and pH 6.8, and pH 6.8-buffer containing 0.1-1% polysorbate 80 or sodium lauryl sulfate. In all test solutions, the microfiltering-HPLC method was able to accomplish continuous sampling of sample solutions, and the recovery rate of theophylline was over 90%. The dissolution behavior by the microfiltering-HPLC method tends to reflect the pharmaceutical design in comparison with the batch-sampling method, and the standard deviations by the microfiltering-HPLC are lower than with the batch-sampling method. In addition, the microfiltering-HPLC method allows many steps to be omitted, such as the filtration, collection and replenishment of sample solutions. These findings provide significant information that can be used in the pharmaceutical development and quality assessment of solid drug products.
  • Simple Determination of a Strongly Aromatic Compound, Sotolon, by Capillary Electrophoresis, Atsushi Taga, Atsushi Sato, Kentaro Suzuki, Manami Takeda, Shuji Kodama, JOURNAL OF OLEO SCIENCE, JOURNAL OF OLEO SCIENCE, 61(1), 45 - 48, Jan. 2012 , Refereed
    Summary:A strongly aromatic compound, sotolon, was assessed by capillary zone electrophoresis within 9 min without specific pre-sample treatment. The calibration curve comprised a straight line with good linearity (R = 0.997) over a relatively wide range of 3.13 to 100 ppm. The precision of this system was excellent with relative standard deviations of 1.39% for migration time and 2.96 % for peak response over 10 repetitions at a concentration of 12.5 ppm. The limit of quantitation and limit of detection values were 3.13 ppm (S/N = 9) and 0.781 ppm (S/N = 3), respectively. Using this system, sotolon was clearly detected from a maple-flavored food additive.
  • Role of the Small GTPase Rho3 in Golgi/Endosome Trafficking through Functional Interaction with Adaptin in Fission Yeast, Ayako Kita, Cuifang Li, Yang Yu, Nanae Umeda, Akira Doi, Mitsuko Yasuda, Shunji Ishiwata, Atsushi Taga, Yoshitaka Horiuchi, Reiko Sugiura, PLOS ONE, PLOS ONE, 6(2), e16842, Feb. 2011 , Refereed
    Summary:Background: We had previously identified the mutant allele of apm1(+) that encodes a homolog of the mammalian mu 1A subunit of the clathrin-associated adaptor protein-1 (AP-1) complex, and we demonstrated the role of Apm1 in Golgi/endosome trafficking, secretion, and vacuole fusion in fission yeast. Methodology/Principal Findings: In the present study, we isolated rho3+, which encodes a Rho-family small GTPase, an important regulator of exocystosis, as a multicopy-suppressor of the temperature-sensitive growth of the apm1-1 mutant cells. Overexpression of Rho3 suppressed the Cl- sensitivity and immunosuppressant sensitivity of the apm1-1 mutant cells. Overexpression of Rho3 also suppressed the fragmentation of vacuoles, and the accumulation of v-SNARE Syb1 in Golgi/endosomes and partially suppressed the defective secretion associated with apm1-deletion cells. Notably, electron microscopic observation of the rho3-deletion cells revealed the accumulation of abnormal Golgi-like structures, vacuole fragmentation, and accumulation of secretory vesicles; these phenotypes were very similar to those of the apm1-deletion cells. Furthermore, the rho3-deletion cells and apm1-deletion cells showed very similar phenotypic characteristics, including the sensitivity to the immunosuppressant FK506, the cell wall-damaging agent micafungin, Cl-, and valproic acid. Green fluorescent protein (GFP)-Rho3 was localized at Golgi/endosomes as well as the plasma membrane and division site. Finally, Rho3 was shown to form a complex with Apm1 as well as with other subunits of the clathrin-associated AP-1 complex in a GTP- and effector domain-dependent manner. Conclusions/Significance: Taken together, our findings reveal a novel role of Rho3 in the regulation of Golgi/endosome trafficking and suggest that clathrin-associated adaptor protein-1 and Rho3 co-ordinate in intracellular transport in fission yeast. To the best of our knowledge, this study provides the first evidence of a direct link between the small GTPase Rho and the clathrin-associated adaptor protein-1 in membrane trafficking.
  • Recovery of molybdenum from fly ash by gibbsite, Fumihiko Ogata, Hisato Tominaga, Hitoshi Yabutani, Atsushi Taga, Naohito Kawasaki, TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY, TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY, 93(4), 635 - 642, 2011
    Summary:The effectiveness of gibbsite (GB), an amorphous aluminum oxide, for the recovery of Mo(VI) from eluates of fly ash of two coal-fired thermal power stations and of roof tile waste was investigated. Upon the qualitative analysis of an eluate of fly ash, 16 elements were detected. Greater amounts of these elements were eluted under acidic conditions (pH 2) than from the neutral or basic eluate of fly ash. GB was used for the adsorption of Mo(VI). Equilibrium adsorption was reached within 1 min. Optimal solution acidity for the adsorption of Mo(VI) onto GB400 (calcined at 400 degrees C) was pH 2. The main adsorption mechanism was ion exchange with a number of hydroxyl groups of GB400. For repeated ad- and desorption of Mo(VI), GB400 could be used at least four times and the recovery percentage of Mo(VI) with sodium hydroxide solution as eluent surpassed 90%. Our results showed that GB400 was very effective for the recovery of Mo(VI) from fly ash.
  • In vitro assay of the interaction between Rnc1 protein and Pmp1 mRNA by affinity capillary electrophoresis with a carboxylated capillary, Atsushi Taga, Ryosuke Satoh, Shunji Ishiwata, Shuji Kodama, Atsushi Sato, Kentaro Suzuki, Reiko Sugiura, JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS, JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS, 53(5), 1332 - 1337, Dec. 2010 , Refereed
    Summary:The interaction between Rnc1, an RNA interactive protein, and a Pmp1 mRNA was investigated by affinity capillary electrophoresis (ACE). Prior to the ACE experiments, the column performances of three capillaries (an untreated fused silica capillary, a polybrene-polyacrylic acid (PB-PAA) double layer coating capillary, and a carboxylated capillary with a covalent modification) were studied with model proteins including ribonuclease B (RNase B) and bovine serum albumin (BSA) Using an untreated fused silica and a PB-PAA double layer coating capillaries, both of the protein peaks were broad and tailing. However, using a carboxylated capillary, the protein peaks were sharp and symmetric, and migration times were repeatable (RSD < 0 4%) Further, the proteins in human serum also gave sharp peaks and its repeatability was kept at a high level by pre-treatment of a capillary inner wall with 1 M sodium chloride solution before each run. An Rnc1 protein was analyzed by ACE with background electrolytes containing various concentrations of Pmp1 sense mRNA using a carboxylated capillary. Increase in the concentration of the mRNA was found to delay the migration time of the protein. But the migration time of the protein was kept constant with increasing Pmp1 anti-sense mRNA instead of Pmp1 sense mRNA A straight line (r=0.987) was obtained by plotting 1/(migration time shift) versus 1/(Pmp1 sense mRNA concentration) and the association constant of Rnc1 protein with Pmp1 sense mRNA could be estimated to be 4 15 x 10(6) M(-1). These results suggest that the association constants of proteins with mRNAs as ligands were easily determined by the proposed method. (C) 2010 Elsevier B.V. All rights reserved.
  • Enantioseparation of DL-isocitric acid by a chiral ligand exchange CE with Ni(II)-D-quinic acid system, Shuji Kodama, Atsushi Taga, Atsushi Yamamoto, Yuji Ito, Yoshitaka Honda, Kentaro Suzuki, Tomohisa Yamashita, Tomoko Kemmei, Sen-ichi Aizawa, ELECTROPHORESIS, ELECTROPHORESIS, 31(21), 3586 - 3591, Oct. 2010 , Refereed
    Summary:The ratio of citric acid to D-isocitric acid can be used to distinguish authentic and adulterated fruit juices. To separate DL-isocitric acid enantiomers, we used ligand exchange CE. D-Quinic acid was used as a chiral selector ligand and Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) ions were used as the central ions of the chiral selector in the BGE. DL-Isocitric acid was found to be enantioseparated with the above metal ions except for Mn(II) ion. The optimum running conditions for the analysis of D- and L-isocitric acids along with citric acid, an isomer of isocitric acid, were found to be a BGE (pH 5.0) containing 30% ACN, 20 mM acetic acid, 20 mM NiSO(4), and 80 mM D-quinic acid. Under these conditions, DL-isocitric and citric acids in fruit juices were analyzed successfully.
  • Metal(II)-ligand molar ratio dependence of enantioseparation of tartaric acid by ligand exchange CE with Cu(II) and Ni(II)-D-quinic acid systems, Shuji Kodama, Sen-ichi Aizawa, Atsushi Taga, Tomohisa Yamashita, Tomoko Kemmei, Kentaro Suzuki, Yoshitaka Honda, Atsushi Yamamoto, ELECTROPHORESIS, ELECTROPHORESIS, 31(6), 1051 - 1054, Mar. 2010 , Refereed
    Summary:Enantioseparation of tartaric acid by ligand exchange CE with a Cu(II)-D-quinic acid system was studied Racemic tartaric acid was enantioseparated by ligand exchange CE using BCEs containing relatively low Cu(II)-D-quinic acid molar ratios ranging from 1 1 to 1.3 and high molar ratios ranging from 1.8 to 1 12 but was not enantioseparated using BGEs with medium molar ratios ranging from 1 4 to 1 6 While the migration order of-D-tartaric acid was prior to L-tartaric acid at the lower Cu(II)-D-quinic acid molar ratios, the enantiomer migration order was reversed at the higher molar ratios. These results were compared with those for Ni(II)-D-quinic acid system The molar ratio dependence of enantiomer migration order can be attributed to a change in the coordination structure of Cu(II) ion with D-quinic acid.
  • Role of the RNA-binding Protein Nrd1 and Pmk1 Mitogen-activated Protein Kinase in the Regulation of Myosin mRNA Stability in Fission Yeast, Ryosuke Satoh, Takahiro Morita, Hirofumi Takada, Ayako Kita, Shunji Ishiwata, Akira Doi, Kanako Hagihara, Atsushi Taga, Yasuhiro Matsumura, Hideki Tohda, Reiko Sugiura, MOLECULAR BIOLOGY OF THE CELL, MOLECULAR BIOLOGY OF THE CELL, 20(9), 2473 - 2485, May 2009 , Refereed
    Summary:Myosin II is an essential component of the actomyosin contractile ring and plays a crucial role in cytokinesis by generating the forces necessary for contraction of the actomyosin ring. Cdc4 is an essential myosin II light chain in fission yeast and is required for cytokinesis. In various eukaryotes, the phosphorylation of myosin is well documented as a primary means of activating myosin II, but little is known about the regulatory mechanisms of Cdc4. Here, we isolated Nrd1, an RNA-binding protein with RNA-recognition motifs, as a multicopy suppressor of cdc4 mutants. Notably, we demonstrated that Nrd1 binds and stabilizes Cdc4 mRNA, thereby suppressing the cytokinesis defects of the cdc4 mutants. Importantly, Pmk1 mitogen-activated protein kinase (MAPK) directly phosphorylates Nrd1, thereby negatively regulating the binding activity of Nrd1 to Cdc4 mRNA. Consistently, the inactivation of Pmk1 MAPK signaling, as well as Nrd1 overexpression, stabilized the Cdc4 mRNA level, thereby suppressing the cytokinesis defects associated with the cdc4 mutants. In addition, we demonstrated the cell cycle-dependent regulation of Pmk1/Nrd1 signaling. Together, our results indicate that Nrd1 plays a role in the regulation of Cdc4 mRNA stability; moreover, our study is the first to demonstrate the posttranscriptional regulation of myosin expression by MAPK signaling.
  • Search for serum protein-binding disaccharides and disaccharide-binding serum proteins by affinity capillary electrophoresis, A Taga, Y Yamamoto, R Maruyama, S Honda, ELECTROPHORESIS, ELECTROPHORESIS, 25(6), 876 - 881, Mar. 2004 , Refereed
    Summary:The potential use of affinity capillary electrophoresis in a microscale search for mutually interacting substances in biological fluid is demonstrated. Some disaccharides, especially gentiobiose (Gen), derivatized with 1-phenyl-3-methyl-5-pyrazolone, caused peak retardation when electrophoresed in a neutral running buffer, containing human serum. Gen, the most significantly retarded disaccharide, was converted to its negatively charged bis-mercaptoethanesulfonate derivative (MerESGen), and a serum sample was analyzed in a neutral buffer containing the derivatized disaccharide. Two peaks, belonging to the beta-globulin fraction, were found to be remarkably retarded in the buffer containing MerES-Gen in a concentration-dependent way. These findings prove an interaction between disaccharides and serum proteins.
  • Colominic acid: a novel chiral selector for capillary electrophoresis of basic drugs, YX Du, A Taga, S Suzuki, WY Liu, S Honda, JOURNAL OF CHROMATOGRAPHY A, JOURNAL OF CHROMATOGRAPHY A, 962(1-2), 221 - 231, Jul. 2002 , Refereed
    Summary:We introduced colominic acid as a new chiral selector for capillary electrophoresis of basic drugs. Use of a low concentration phosphate buffer containing this polysaccharide and a Polybrene/colominic acid double coated capillary allowed excellent separation of the enantiomers of primaquine, chloroquine and tryptophan. Other drugs giving partial enantioseparation include laudanosine and salbutamol. Capillary coating with Polybrene followed by colominic acid eliminated the problems of peak tailing and low reproducibility of migration time in uncoated capillaries. The optimum pH was in the acidic region but varied among drugs. A low capillary temperature of 16 degreesC and a colominic acid concentration of 9 w/v% are recommended for practical analysis of these drugs. Colominic acid preparations having higher molecular masses gave better enantioseparation, and N-acletylneuraminic acid, the component monosaccharide, did not give any enantioseparation. (C) 2002 Elsevier Science B.V. All rights reserved.

Books etc

  • Capillary Electrophoresis of Carbohydrate (Methods in Molecular Biology, Vol. 213) edited by P. Thibault and S. Honda, Humana Press Inc,   2003
  • Capillary Electrophoresis of Carbohydrate (Methods in Molecular Biology, Vol. 213) edited by P. Thibault and S. Honda, Humana Press Inc,   2003
  • Carbohydrate Analysis by modern Chromatography and Electrophoresis, Elsevier Science B. V.,   2002

Conference Activities & Talks

  • MAP kinase signaling regulates stress granule formation via the RNA-binding protein Nrd1,   2011 06
  • MAP kinase signaling-dependent regulation of stress granule formation mediated by the RNA-binding protein Nrd1 in fission yeast,   2011 06
  • MAP Kinase Signaling Dependent Regulation of Cell Fate Mediated by the RNA-binding protein Nrd1 in Fission yeast, The 19th CDB Meeting RNA Sciences in Cell and Developmental Biology,   2010 05 , The 19th CDB Meeting RNA Sciences in Cell and Developmental Biology
  • Observation of Interaction between RNA and GFP-Protein by Affinity Capillary Electrophoresis, 29 th International Symposium on the ?Separation of Proteins, Peptides and Polynucleotides,   2008 09 , 29 th International Symposium on the ?Separation of Proteins, Peptides and Polynucleotides
  • Study of RNA-protein interaction in MAP kinase signaling by affinity capillary electrophoresis with a carboxylated capillary, 28 th International Symposium on the ?Separation of Proteins, Peptides and Polynucleotides,   2008 09 , 28 th International Symposium on the ?Separation of Proteins, Peptides and Polynucleotides
  • Development of a novel type capillary for protein analysis by capillary electrophoresis, EUROanalysis XIV,   2007 09 , EUROanalysis XIV
  • Reproducible Analysis of Carbohydrate Derivatives by Capillary Electrophoresis, XXIIIrd International carbohydrate symposium (ICS2006),   2006 07 , XXIIIrd International carbohydrate symposium (ICS2006)
  • CAPILLARY ELECYTROPHORESIS OF NEUTRAL CARBOHYDRATES, 4th Separation in the BioScienses (SBS’05),   2005 09 , 4th Separation in the BioScienses (SBS’05)
  • Capillary Electrophoresis of Human Erythrocytes for Observation of Their Interaction with Lectins, ASIANALYSIS VII,   2004 07 , ASIANALYSIS VII


  • Analysis of interaction between nucleic acid and protein by affinity capillary electrophoresis, 特願2009-207005, 特開2011-055741
  • Trainig kit and methods for anti-tumor cancer injection mixing, 特願2009-249404

Awards & Honors

  •   2005 , クロマトグラフィー科学会奨励賞

Research Grants & Projects

  • Study of Microchip Electrophoresis
  • Study of Surface Plasmon Resonance
  • Study of High Performance Capillary Electrophoresis