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Shinobu SAKAI

s-sakai@nihs.go.jp

Journal articles

2008
 
PMID 
Shinobu SAKAI, Rieko MATSUDA, Reiko ADACHI, Hiroshi AKIYAMA, Tamio MAITANI, Yasuo OHNO, Michihiro Oka, Akihisa Abe, Kohsuke SEIKI, Hiroshi Oda, Kazuo SHIOMI, Atsuo URISU (2008)  Interlaboratory evaluation of two enzyme-linked immunosorbent assay kits for the determination of crustacean protein in processed foods.   J AOAC Int 91: 1. 123-129 Jan/Feb  
Abstract: The labeling of foods containing material derived from crustaceans such as shrimp and crab is to become mandatory in Japan because of increases in the number of allergy patients. To ensure proper labeling, 2 novel sandwich enzyme-linked immunosorbent assay (ELISA) kits for the determination of crustacean protein in processed foods, the N kit (Nissui Pharmaceutical Co., Ltd, Ibaraki, Japan) and the M kit (Maruha Nichiro Holdings, Inc., Ibaraki, Japan), have been developed. Five types of model processed foods containing 10 and/or 11.9 microg/g crustacean soluble protein were prepared for interlaboratory evaluation of the performance of these kits. The N kit displayed a relatively high level of reproducibility relative standard deviation (interlaboratory precision; 4.0-8.4% RSDR) and sufficient recovery (65-86%) for all the model processed foods. The M kit displayed sufficient reproducibility (17.6-20.5% RSDR) and a reasonably high level of recovery (82-103%). The repeatability relative standard deviation (RSDr) values regarding the detection of crustacean proteins in the 5 model foods were mostly < 5.1% RSDr for the N kit and 9.9% RSDr for the M kit. In conclusion, the results of this interlaboratory evaluation suggest that both these ELISA kits would be very useful for detecting crustacean protein in processed foods.
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2007
 
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PMID 
Hiromu Taguchi, Satoshi Watanabe, Takashi Hirao, Hiroshi Akiyama, Shinobu Sakai, Takahiro Watanabe, Rieko Matsuda, Atsuo Urisu, Tamio Maitani (2007)  Specific detection of potentially allergenic kiwifruit in foods using polymerase chain reaction.   J Agric Food Chem 55: 5. 1649-1655 Mar  
Abstract: Kiwifruit (Actinidia deliciosa and Actinidia chinensis) is allergenic to sensitive patients, and, under Japanese regulations, it is one of the food items that are recommended to be declared on food labeling as much as possible. To develop PCR-based methods for the detection of trace amounts of kiwifruit in foods, two primer pairs targeting the ITS-1 region of the Actinidia spp. were designed using PCR simulation software. On the basis of the known distribution of a major kiwifruit allergen (actinidin) within the Actinidia spp., as well as of reports on clinical and immunological cross-reactivities, one of the primer pairs was designed to detect all Actinidia spp. and the other to detect commercially grown Actinidia spp. (i.e., kiwifruit, Actinidia arguta, and their interspecific hybrids) except for Actinidia polygama. The specificity of the developed methods using the designed primer pairs was verified by performing PCR experiments on 8 Actinidia spp. and 26 other plants including fruits. The methods were considered to be specific enough to yield target-size products only from the target Actinidia spp. and to detect no target-size products from nontarget species. The methods were sensitive enough to detect 5-50 fg of Actinidia spp. DNA spiked in 50 ng of salmon testis DNA used as a carrier (1-10 ppm of kiwifruit DNA) and 1700 ppm (w/w) of fresh kiwifruit puree spiked in a commercial plain yogurt (corresponding to ca. 10 ppm of kiwifruit protein). These methods would be expected to be useful in the detection of hidden kiwifruit and its related species in processed foods.
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PMID 
Shinobu Sakai, Eri Otake, Toshihiko Toida, Yukihiro Goda (2007)  Identification of the origin of chondroitin sulfate in "health foods".   Chem Pharm Bull (Tokyo) 55: 2. 299-303 Feb  
Abstract: Twelve "health foods" products containing chondroitin sulfate (CS) were purchased from the Japanese market and the origin of the CS was investigated by conducting disaccharide compositional analysis after enzymatic depolymerization and by 1H-NMR spectroscopy. Nine of the 12 products had labels indicating that the origin of the CS was shark cartilage. However, two of them were found to contain mammalian CS. Next, we compared the ratio of the sulfate group to the galactosamine residue after the acid hydrolysis of CS. The results suggest that all of the CS from sharks had a ratio of more than 1.0, while the CS from mammals had a ratio of less than 1.0. Since this comparative analysis does not require expensive purified enzyme, it would be an economical way to identify the origin of CS in "health foods." Being able to determine the origin of the ingredients in natural products is very important for ensuring their quality, safety, and efficacy. Therefore, we think that regulatory requirements for accurately indicating the origin of "health foods" and effective enforcement of these requirements are needed.
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Kosuke SEIKI, Hiroshi Oda, Hisashi YOSHIOKA, Shinobu SAKAI, Atsuo URISU, Hiroshi AKIYAMA, Yasuo OHNO (2007)  A reliable and sensitive immunoassay for the determination of crustacean protein in processed foods.   Journal of Agricultural and Food Chemistry 55: 23. 9345-9350 Nov  
Abstract: Among food allergens, crustacea such as shrimps, crabs, and lobsters are a frequent cause of adverse food reactions in allergic patients. The major allergen has been identified as a muscular protein, tropomyosin. A novel sandwich enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of crustacean protein in processed foods was developed using the sample dilution buffer that is added to porcine tropomyosin. The sandwich ELISA method was highly specific for the Decapoda group, apart from minor cross-reactivities to other crustacea and mollusks. The recovery ranged from 85 to 141%, while the intra- and interassay coefficients of variation were less than 2.8 and 8.4%, respectively.
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Hirohito Yamakawa, Hiroshi Akiyama, Yumi Endo, Kiyoko Miyatake, Kozue Sakata, Shinobu Sakai, Tatsuya Moriyama, Atsuo Urisu, Tamio Maitani (2007)  Specific detection of soybean residues in processed foods by the polymerase chain reaction.   Biosci Biotechnol Biochem 71: 1. 269-272 Jan  
Abstract: A sensitive qualitative detection method for soybeans in foods by using the polymerase chain reaction (PCR) was developed. For specific detection of soybeans with high specificity, the primer pair of Gym 81/Gym 82 was designed on the gene encoding the Glycine max repetitive sequence. The trace amount of soybeans in commercial food products could be qualitatively detected by this method.
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Shinobu SAKAI, Kana HIRANO, Hidenao TOYODA, Robert J LINHARDT, Toshihiko TOIDA (2007)  Matrix assisted laser desorption ionization-time of flight mass spectrometry analysis of hyaluronan oligosaccharides.   Analytica Chimica Acta 593: 2. 207-213 Jun  
Abstract: A new method is presented for the identification of oligosaccharides obtained by enzymatic digestion of hyaluronan (HA) with bacterial hyaluronidase (E.C. 4.2.2.1, from Streptomyces hyalurolyticus) using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOFMS). Mixtures containing HA oligosaccharides of tetrasaccharide (4-mer)-34-mer were analyzed using this method. The carboxyl groups of the glucuronate residues in the prepared HA oligomers, were modified as the acidic form (-COOH), sodium salts (-COONa), organic ammonium salts, or methylesters before MALDI-TOFMS measurement. Among these samples, the methylester form of glucuronate residues in HA oligosaccharides, prepared by methylation using trimethylsilyl diazomethane, afforded high sensitivity for spectra. This simple modification method for carboxyl group methylation of acidic polysaccharides [Hirano et al., Carbohydr. Res., 340, (2005) 2297-2304] provides samples suitable for MALDI-TOF mass spectrometric analysis throughout a significantly enhanced range of masses.
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PMID 
Hirohito YAMAKAWA, Hiroshi AKIYAMA, Yumi ENDO, Kiyoko MIYATAKE, Kozue SAKATA, Shinobu SAKAI, Masatake TOYODA, Atsuo URISU (2007)  Specific detection of wheat residues in processed foods by polymerase chain reaction.   Bioscience, Biotechnology, and Biochemistry 71: 10. 2561-2564 Oct  
Abstract: A sensitive qualitative detection method for wheat in foods using polymerase chain reaction (PCR) was developed. Trace amounts of wheat in commercial food products could be qualitatively detected by this method. The sensitivity of the proposed PCR method appears to be similar to that of ELISA. The present method should be very useful for detecting wheat residues in processed foods.
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PMID 
Takeo YANO, Yumiko SAKAI, Kohji UCHIDA, Yoshiki NAKAO, Kimie ISHIHATA, Shigeru NAKANO, Toshihiro YAMADA, Shinobu SAKAI, Atsuo URISU, Hiroshi AKIYAMA, Tamio MAITANI (2007)  Detection of walnut residues in processed foods by polymerase chain reaction.   Bioscience, Biotechnology, and Biochemistry 71: 7. 1793-1796 Jul  
Abstract: A sensitive qualitative detection method for walnut (Juglans regia) using polymerase chain reaction (PCR) was developed. For detection of walnuts with high specificity, the primer pair WAL-F/WAL-R was designed based on walnut matK genes. Trace amounts of walnuts in commercial food products can be qualitatively detected using this method.
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Takashi OHTSUKI, Emiko YOKOSAWA, Takashi KOYANO, Srisomporn PREEPRAME, Thaworn KOWITHAYAKORN, Shinobu SAKAI, Toshihiko TOIDA, Masami ISHIBASHI (2007)  Quinic acid esters from Pluchea indica with collagenase, MMP-2 and MMP-9 inhibitory activities.   Phytotherapy Research 22: 2. 264-266 Aug  
Abstract: Investigation of collagenase inhibitory natural components afforded two quinic acid esters (1 and 2) and quercetin (3) from the leaves of Pluchea indica (Compositae). Of these, compounds 1 and 2 exhibited collagenase inhibitory activity (IC(50)) at a concentration of less than 10 microm, and 1 showed matrix metalloproteinase (MMP)-2 and -9 inhibitory activity (IC(50)) at 2.5 and 6.4 microm, respectively. Copyright (c) 2007 John Wiley & Sons, Ltd.
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PMID 
Shuichi KUSANO, Atsuko OOTANI, Shinobu SAKAI, Naoko IGARASHI, Atsuko TAKEGUCHI, Hidenao TOYODA, Toshihiko TOIDA (2007)  HPLC determination of chondrosine in mouse blood plasma after intravenous or oral dose.   Biological & Pharmaceutical Bulletin 30: 8. 1365-1368 Aug  
Abstract: The bioavailability of chondrosine was evaluated by its direct measurement as found in the blood plasma following removal of plasma proteins by perchloric acid. The postcolumn HPLC determination of chondrosine was performed on an SCX column (6 mm i.d.x 150 mm), 0.35 mol/l boric acid (pH 5.2 adjusted by 0.1 mol/l NaOH) as an eluent (0.9 ml/min), 0.5% 2-cyanoacetamide and 1.0 M NaOH as fluorogenic reagents (0.25 ml/min each) with a fluorescence detector (ex. 331nm, em. 383nm). Two separate animal studies were conducted. In study 1, adult male ddY mice (n=6) received i.v. chondrosine (1.0 mg/kg body weight) and the plasma samples were collected. In the second study, 6 adult male ddY mice received p.o. chondrosine (400 mg/kg body weight) and the plasma samples were collected. Blood plasma samples were deproteinized by perchloric acid, analyzed and the bioavailability of chondrosine was determined. Twenty five to fifty microliters of blood plasma were required for the assay. Chondrosine was absorbed after oral administration with two phases having two maximum values, 7.8+/-5.4 and 4.0+/-1.9 at 15 microg/ml and 120 min, respectively; it disappeared from the blood flow very quickly after intravenous administration. This study provides the first report of the bioavailability of orally administered chondrosine in mice.
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2006
 
PMID 
Shuichi Kusano, Naoko Igarashi, Shinobu Sakai, Toshihiko Toida (2006)  Effect of orally administered chondrosine on uptake of 35S sulfate into rat cartilage   Yakugaku Zasshi 126: 4. 297-300 Apr  
Abstract: Chondroitin sulfate is widely distributed in animal tissues and possibly plays an important role in different types of metabolic reactions as well as protecting joints, the internal wall of blood vessels, skin, bone, etc. In cartilage, glycosaminoglycans have a protective function; in particular, chondroitin sulfate stabilizes fibrous and cellular elements of the connective tissue and, at the same time, lubricates and protects the membranes in joints. Recently, chondroitin sulfate has been used as a nutraceutical for the treatment of joint diseases such as osteoarthritis, although acidic and large molecules such as chondroitin sulfate might not be able to be absorbed through digestive apparatus such as the intestine. In this study, we investigated the effects of orally administered chondrosine derived from shark chondroitin sulfate on the uptake of inorganic (35)S sulfate into rat cartilage and found that chondrosine stimulates the incorporation of (35)S sulfate into cartilage compared with intact chondroitin sulfate.
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Shinobu Sakai, Hiroshi Akiyama, Yuji Sato, Yasuo Yoshioka, Robert J Linhardt, Yukihiro Goda, Tamio Maitani, Toshihiko Toida (2006)  Chondroitin sulfate intake inhibits the IgE-mediated allergic response by down-regulating Th2 responses in mice.   J Biol Chem 281: 29. 19872-19880 Jul  
Abstract: Chondroitin sulfate (CS) was administered orally to BALB/c mice immunized intraperitoneally with ovalbumin (OVA) and/or dinitrophenylated OVA. The titers of antigen-specific IgE and IgG1 in mouse sera were determined. The antigen-specific IgE production by mice fed ad libitum with CS was significantly inhibited. We also examined the effect of feeding CS on immediate-type hypersensitivity. One hour after antigen stimulation, the ears of mice fed with CS swelled less than those of the control mice. Furthermore, the rise in serum histamine in the mice fed with CS under active systemic anaphylaxis was significantly lower than that in the controls. We next examined the pattern of cytokine production by splenocytes from mice followed by re-stimulation with OVA in vitro. The splenocytes from the mice fed with CS produced less interleukin (IL)-5, IL-10, and IL-13 than those from the control group. In contrast, the production of interferon-gamma and IL-2 by the splenocytes of mice fed with CS was not significantly different from those in the control mice. In addition, the production of transforming growth factor-beta from the splenocytes of mice fed with CS was significantly higher than that of the control mice. Furthermore, we showed that the percentages of CD4(+) cells, CD8(+) cells, and CD4(+)CD25(+) cells in the splenocytes of mice fed with CS are significantly higher than those of the control. These findings suggest that oral intake of CS inhibits the specific IgE production and antigen-induced anaphylactic response by up-regulating regulatory T-cell differentiation, followed by down-regulating the Th2 response.
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2005
 
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PMID 
Kana Hirano, Shinobu Sakai, Tsutomu Ishikawa, Fikri Y Avci, Robert J Linhardt, Toshihiko Toida (2005)  Preparation of the methyl ester of hyaluronan and its enzymatic degradation.   Carbohydr Res 340: 14. 2297-2304 Oct  
Abstract: A methyl ester of hyaluronan in which the carboxyl groups were fully esterified was prepared using trimethylsilyl diazomethane. This derivative, while not depolymerized by hyaluronan lyases or hyaluronan hydrolases, was a substrate for both chondroitin ACI lyase (EC 4.2.2.5) from Flavobacterium heparinum and chondroitin ACII lyase (EC 4.2.2.5) from Arthrobacter aurescens. The major product isolated in these depolymerization reactions was methyl alpha-L-threo-hex-4-enepyranosyluronate-(1-->3)-2-acetamido-2-deoxy-alpha,beta-D-glucopyranoside as determined by 1H NMR spectroscopy and MALDITOF mass spectrometry.
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Kenji Hoshino, Emi Momiyama, Kaori Yoshida, Kazuhiro Nishimura, Shinobu Sakai, Toshihiko Toida, Keiko Kashiwagi, Kazuei Igarashi (2005)  Polyamine transport by mammalian cells and mitochondria: role of antizyme and glycosaminoglycans.   J Biol Chem 280: 52. 42801-42808 Dec  
Abstract: The role of antizyme (AZ) and glycosaminoglycans in polyamine uptake by mammalian cells and mitochondria was examined using NIH3T3 and FM3A cells and rat liver mitochondria. AZ is synthesized as two isoforms (29 and 24.5 kDa) due to the existence of two initiation codon AUGs in the AZ mRNA. Most AZ existed as the 24.5-kDa form translatable from the second AUG, but a portion of the 29-kDa AZ from the first AUG was associated with mitochondria because of the presence of a mitochondrial targeting signal between the first and the second methionine. The predominance of the 24.5-kDa isoform was mainly due to the presence of spermidine and a favorable sequence context (Kozak sequence) at the second initiation codon AUG. Spermine uptake by NIH3T3 cells was inhibited by both 29- and 24.5-kDa AZs, but uptake by rat liver mitochondria was not influenced by either form of AZ. Because spermine uptake by mitochondria caused a release of cytochrome c, an enhancer of apoptosis, we looked for inhibitors of mitochondrial spermine uptake other than AZ. Cations such as Na+, K+, and Mg2+ were inhibitors of the mitochondrial uptake. It has been reported that heparan sulfate on glypican-1 plays important roles in spermine uptake by human embryonic lung fibroblasts. Heparin, but not heparan sulfate, slightly inhibited spermine uptake by FM3A cells in the absence of Mg2+ and Ca2+ but had no effect under physiological conditions in the presence of Mg2+ and Ca2+.
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2004
 
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Hiroshi Akiyama, Shinobu Sakai, Robert J Linhardt, Yukihiro Goda, Toshihiko Toida, Tamio Maitani (2004)  Chondroitin sulphate structure affects its immunological activities on murine splenocytes sensitized with ovalbumin.   Biochem J 382: Pt 1. 269-278 Aug  
Abstract: Chondroitin sulphate (CS) is a glycosaminoglycan widely distributed in animal tissues, which has anti-inflammatory and chondroprotective properties. We reported previously that chondroitin 4-sulphate (CS-A) up-regulates the antigen-specific Th1 immune response of murine splenocytes sensitized with ovalbumin in vitro, and that CS suppresses the antigen-specific IgE responses. We now demonstrate that a specific sulphation pattern of the CS polysaccharide is required for the Th1-promoted activity, as other polysaccharides such as dextran and dextran sulphate do not significantly induce this activity. While the presence of some O-sulpho groups appear to be essential for activity, CS-A, and synthetically prepared, partially O-sulphonated CS, induce higher Th1-promoted activity than synthetically prepared, fully O-sulphonated CS. CS-A induces an activity greater than chondroitin sulphate B (CS-B) or chondroitin 6-sulphate (CS-C). In addition, chondroitin sulphate E (CS-E) induces greater activity than CS-A or CS-D. These results suggest that the GlcA(beta1-3)GalNAc(4,6-O-disulpho) sequence in CS-E is important for Th1-promoted activity. Furthermore, rat anti-mouse CD62L antibody, an antibody to L-selectin, inhibits the Th1-promoting activity of CS. These results suggest that the Th1-promoted activity could be associated with L-selectin on lymphocytes. These findings describe a new mechanism for the anti-inflammatory and chondroprotective properties of CS that may be useful in designing new therapeutic applications for CS used in the treatment of immediate-type hypersensitivity.
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Takashi Ohtsuki, Takashi Koyano, Thaworn Kowithayakorn, Shinobu Sakai, Nobuo Kawahara, Yukihiro Goda, Naoto Yamaguchi, Masami Ishibashi (2004)  New chlorogenin hexasaccharide isolated from Agave fourcroydes with cytotoxic and cell cycle inhibitory activities.   Bioorg Med Chem 12: 14. 3841-3845 Jul  
Abstract: A new chlorogenin hexasaccharide (1) was isolated from leaves of Agave fourcroydes (Agavaceae). The structure of the new saponin was elucidated as chlorogenin 3-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside] (1) by spectroscopic analysis and the result of acidic hydrolysis. The new saponin (1) as well as known hexasaccharides (3 and 5) isolated here showed cytotoxicity against HeLa cells, and 1 exhibited a cell cycle inhibitory effect at the G2/M stage at the concentration of 7.5 and 10 microg/mL.
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2003
 
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Haruyo Okunuki, Reiko Teshima, Naoki Harikai, Shinobu Sakai, Hiroshi Akiyama, Tamio Maitani, Jun-Ichi Sawada (2003)  Oral sensitization of W/W(v) mice with ovalbumin and possible involvement of the decrease in gammadelta-T cells.   Biol Pharm Bull 26: 9. 1260-1265 Sep  
Abstract: Mast-cell-deficient WBB6F1-W/W(v) mice (W/W(v)) and congenic wild-type (+/+) mice were sensitized by oral administration of 0.1 or 1.0 mg ovalbumin (OVA) in the form of gavage every day for 9 weeks, and active systemic anaphylaxis (ASA) was induced by intraperitoneal injection of OVA. Production of OVA-specific IgG1 in response to oral sensitization of the W/W(v) mice was very high, and the production of IL-4, IL-5 and IL-10 by splenocytes re-stimulated with OVA in vitro was increased. These findings suggest that Th2-dominant helper T-cell activation had occurred. By contrast, production of OVA-specific IgG1 was low in +/+ mice, and no significant increase in production of Th2-type cytokines by the splenocytes of +/+ mice was observed. Population analysis in Peyer's patches by flow cytometry revealed that the proportion of the CD11c(+) cell in the W/W(v) mice was slightly increased after antigen stimulation. Analysis of the cell surface markers of intraepithelial lymphocytes (IELs) by flow cytometry showed that the proportion of TCRgammadelta-T cells was extremely lower in the W/W(v) mice, especially in the antigen sensitized group. The proportion of TCRgammadelta-T cells in the splenocytes of W/W(v) mice was also lower than in +/+ mice. Taken together, the above findings indicate that W/W(v) mice seems to be a good model not only for studying the induction mechanism of food allergy but for examining the role of TCRgammadelta-T cells in food-induced hypersensitivity.
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Shinobu Sakai, Wan Seok Kim, In Sun Lee, Yeong Shik Kim, Ayako Nakamura, Toshihiko Toida, Toshio Imanari (2003)  Purification and characterization of dermatan sulfate from the skin of the eel, Anguilla japonica.   Carbohydr Res 338: 3. 263-269 Jan  
Abstract: Glycosaminoglycans were isolated from the eel skin (Anguilla japonica) by actinase and endonuclease digestions, followed by a beta-elimination reaction and DEAE-Sephacel chromatography. Dermatan sulfate was the major glycosaminoglycan in the eel skin with 88% of the total uronic acid. The content of the IdoA2Salpha1-->4GalNAc4S sequence in eel skin, which shows anticoagulant activity through binding to heparin cofactor II, was two times higher than that of dermatan sulfate from porcine skin. The anti-IIa activity of eel skin dermatan sulfate was determined to be 2.4 units/mg, whereas dermatan sulfate from porcine skin shows 23.2 units/mg. The average molecular weight of dermatan sulfate was determined by gel chromatography on a TSKgel G3000SWXL column as 14 kDa. Based on 1H NMR spectroscopy, the presence of 3-sulfated and/or 2,3-sulfated IdoA residues was suggested. The reason why highly sulfated dermatan sulfate does not show anticoagulant activity is discussed. In addition to dermatan sulfate, the eel skin contained a small amount of keratan sulfate, which was identified by keratanase treatment.
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2002
 
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Shinobu Sakai, Jun-ichi Onose, Haruka Nakamura, Hidenao Toyoda, Toshihiko Toida, Toshio Imanari, Robert J Linhardt (2002)  Pretreatment procedure for the microdetermination of chondroitin sulfate in plasma and urine.   Anal Biochem 302: 2. 169-174 Mar  
Abstract: A new, simple, and rapid pretreatment method for the determination of chondroitin sulfate, dermatan sulfate, and hyaluronan from urine and blood plasma samples has been developed. Plasma proteins were first converted into small peptides by digestion using a nonspecific protease, actinase E, and the resulting small peptides were removed by centrifugal filtration. The retained, residual crude glycosaminoglycans, including chondroitin/dermatan sulfates and hyaluronan, were converted into unsaturated disaccharides through the action of chondroitin sulfate lyses. Next, these disaccharides were recovered and purified using centrifugal filtration together with DeltaDi-UA2S, added as an internal standard. The filtered disaccharide mixture was analyzed by HPLC with fluorometric postcolumn derivatization using 2-cyanoacetamide as a fluorogenic reagent. This method was applied to a pharmacokinetic study of chondroitin sulfate administered intravenously to mice. The half-life of the administered chondroitin sulfates, having molecular masses from 6 to 50 kDa, varied depending on their molecular sizes. This new method should be useful for studies on the metabolic fate of exogenously administered glycosaminoglycans in small experimental animals.
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Shinobu Sakai, Hiroshi Akiyama, Naoki Harikai, Hidenao Toyoda, Toshihiko Toida, Tamio Maitani, Toshio Imanari (2002)  Effect of chondroitin sulfate on murine splenocytes sensitized with ovalbumin.   Immunol Lett 84: 3. 211-216 Dec  
Abstract: Chondroitin sulfate (CS) is a glycosaminoglycan that is widely present in animals organisms, and it has anti-inflammatory and chondroprotective properties. To examine the effects of CS on the immune system, splenocytes obtained from ovalbumin (OVA)-sensitized BALB/c mice were challenged with OVA in the presence of CS, and cytokine levels in the medium of the cultured cells were measured. CS induced secretion of Th1-type cytokines (IFN-gamma, IL-2, and IL-12) by OVA-sensitized splenocytes but suppressed secretion of Th2-type cytokines (IL-5 and IL-10). Flow cytometric assay showed a significantly higher percentage of helper T cells (CD4(+)CD8(-) cells) among the splenocytes cultured with OVA and CS than with OVA alone. Analysis of the IFN-gamma mRNA level of the splenocytes by the real-time quantitative RT-PCR technique revealed higher levels in the splenocytes cultured with OVA and CS than in the splenocytes cultured with OVA alone. This is the first demonstration that CS inhibits antigen-induced IgE production through induction of cytokine secretion by Th1 cells, and this finding suggests a potential use of CS in preventing IgE-mediated allergy.
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1998
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