JaLCDOI 10.18926/AMO/32307
フルテキストURL fulltext.pdf
著者 Wrobel, Maria| Ubuka, Toshihiko| Yao, Wen-Bin| Abe, Tadashi|
抄録 <p>The effect of exogenous thyroxine (T4) administration on the activity of rhodanese, cystathionase, and 3-mercaptopyruvate sulfurtransferase (MPST) in the mitochondrial and cytosolic fractions of mouse liver was investigated. Three groups of mice were treated for 6 consecutive days with subcutaneous injections of T4 (50 micrograms, 100 micrograms, and 250 micrograms per 100 g of body wt, respectively). The other 3 groups were given 100 micrograms of T4 per 100 g of body wt for 1, 2, or 3 days. The dose of 100 micrograms T4 per 100 g of body wt given for 6 days exerted the strongest effect on the activity of all of the investigated enzymes. In comparison to the control, rhodanese activity diminished in the mitochondrial fraction by 40% (P &#60; 0.05), cystathionase activity diminished in the cytosolic fraction by 15% (P &#60; 0.05), and MPST activity in the mitochondrial fraction was reduced by 34% (P &#60; 0.05), whereas cytosolic MPST activity was unaltered. Simultaneously, in the liver homogenate, elevated levels of ATP and sulfate were observed after 6 days of T4 administration. Thus, the present results seem to suggest that in the mouse liver, after 6 days of administration of 100 micrograms T4 per 100 g of body wt, the desulfuration metabolism of L-cysteine is diminished, which is probably accompanied by an increase in oxidative L-cysteine metabolism. The dose of 100 micrograms per 100 g of body wt administered for a shorter period, and the use of a lower dosage (50 micrograms T4 per 100 g of body wt) for 6 days had a stimulatory effect upon MPST activity level, and an increased level of sulfane sulfur was observed.</p>
キーワード thyroxine rhodanese 3-mercaptopyruvate sulfurtransferase cystathionase sulfane sulful
Amo Type Article
発行日 2000-02
出版物タイトル Acta Medica Okayama
54巻
1号
出版者 Okayama University Medical School
開始ページ 9
終了ページ 14
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 10709617
Web of Science KeyUT 000085526000002
JaLCDOI 10.18926/AMO/31647
フルテキストURL fulltext.pdf
著者 Kurozumi, Yoshiatsu| Abe, Tadashi| Yao, Wen-Bin| Ubuka, Toshihiko|
抄録 <p>Experimental beta-alaninuria was induced in rats by injection of (aminooxy)acetate (AOA), a potent inhibitor of aminotransferases, in order to elucidate the pathogenesis of hyper-beta-alaninemia. A 27-fold increase of beta-alanine (BALA) excretion was induced by subcutaneous injection of 1 5 mg of AOA per kg of body weight. A 13-fold and a 9-fold increase of beta-aminoisobutyric acid (BAIBA) and gamma-aminobutyric acid (GABA), respectively, were also induced simultaneously by the AOA injection. Identification of BALA and BAIBA isolated from the rat urine was performed by chromatographic and mass spectrometric analyses. The effects of AOA injection on the tissue levels of these amino acids were also studied. Contents of BALA in the liver and kidney and GABA in the brain increased significantly in response to AOA injection. The present study indicates that BALA transaminase is involved in hyper-beta-alaninemia.</p>
キーワード beta-alanine beta-aminoisobutyric acid ganma-amlnobutyric-acid (aminooxy)acetate aminotransferase
Amo Type Article
発行日 1999-02
出版物タイトル Acta Medica Okayama
53巻
1号
出版者 Okayama University Medical School
開始ページ 13
終了ページ 18
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
Web of Sience KeyUT 000078897700003
JaLCDOI 10.18926/AMO/31315
フルテキストURL fulltext.pdf
著者 Yukihiro, Keishi| Tomozawa, Masaru| Abe, Tadashi| Yao, Wen-Bin| Ohta, Jun| Ubuka, Toshihiko|
抄録 <p>Sulfate and taurine are the main metabolites of L-cysteine in mammals and are excreted in the urine. The effect of a high protein diet on the ratio of sulfate to taurine excretion was studied in rats using synthetic 25% (standard protein diet group, group A) and 40% (high protein diet group, group B) casein diets. Average taurine and sulfate excretions (mumol/kg of body weight per day) were 280.4 +/- 93.8 and 943.2 +/- 144.8 in group A and 553.4 +/- 124.5 and 2675.0 +/- 390.9 in group B, respectively. Thus, the average taurine/sulfate ratio in group A was 0.30 +/- 0.08. By a single administration of 5 mmol of L-cysteine/kg of body weight in group A, the average taurine and sulfate excretions increased to 1127.5 +/- 120.2 and 4043.0 +/- 305.6, respectively, but the taurine/sulfate ratio changed only slightly (0.28). The average taurine/sulfate ratio in group B was 0.22 +/- 0.07, a significantly lower ratio than that in group A, which means that daily intake of a high protein diet resulted in more sulfate excretion. The taurine/sulfate ratio in group B was affected only slightly (0.19) by the cysteine administration as well. These results suggest that the ratio of taurine and sulfate production was determined by dietary protein content and that the increase in sulfate production is larger than that of taurine production when the intake of dietary protein is increased.</p>
キーワード high protein diet sulfate taurine cysteine metabolism
Amo Type Article
発行日 1998-04
出版物タイトル Acta Medica Okayama
52巻
2号
出版者 Okayama University Medical School
開始ページ 71
終了ページ 75
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 9588221
Web of Science KeyUT 000073363000001
JaLCDOI 10.18926/AMO/31312
フルテキストURL fulltext.pdf
著者 Tomozawa, Masaru| Yukihiro, Keishi| Yao, Wen-Bin| Abe, Tadashi| Ohta, Jun| Ubuka, Toshihiko|
抄録 <p>The effects of a low protein diet on the excretion of sulfate and taurine, major metabolites of L-cysteine in mammals, were studied in rats fed with synthetic 10% (group A) and 25% (group B) casein diets. The average excretions of total taurine (taurine plus hypotaurine) and total sulfate (free plus ester sulfate) (mumol/kg of body weight per day after the adaptation to the synthetic diet) in group A were 14.2 +/- 13.4 and 122.3 +/- 39.6, respectively, which were very low compared with 280.4 +/- 93.8 and 943.2 +/- 144.8, respectively, in group B. The taurine/sulfate ratio in group A was 0.12 +/- 0.11, which was significantly lower than that (0.30 +/- 0.08) in group B. A single intraperitoneal injection of 5 mmol of L-cysteine per kg of body weight in group A resulted in an increase in average taurine and sulfate excretion to 693.4 +/- 195.6 and 2440.6 +/- 270.0, respectively, and thus the average taurine/sulfate ratio increased to 0.29. These increases were transient and low taurine excretion resumed again 24 h after the L-cysteine administration. L-Cysteine injection in group B resulted in a similar increase in taurine and sulfate excretion, but the ratio changed only slightly (0.28). The present results suggest that in vivo production of taurine is reduced preferentially over sulfate production when sulfur amino acid supply is limited. </p>
キーワード low protein diet taurine sulfate crstein metabolism
Amo Type Article
発行日 1998-04
出版物タイトル Acta Medica Okayama
52巻
2号
出版者 Okayama University Medical School
開始ページ 77
終了ページ 81
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 9588222
Web of Science KeyUT 000073363000002
JaLCDOI 10.18926/AMO/30413
フルテキストURL fulltext.pdf
著者 Zhao, Yuan-Qing| Kinuta, Masahiro| Abe, Tadashi| Yao, Wen-Bin| Ubuka, Toshihiko|
抄録 <p>The effects of intraperitoneal administration of 2-(4-carboxy-D-gluco-tetrahydroxybutyl)thiazolidine-4-carboxylic acid (CGUA), a cysteine derivative conjugated with glucuronic acid, on total glutathione and total cysteine contents in rat tissues were investigated. Total glutathione (GSH and GSSG) and total cysteine (cysteine and cystine) were determined by a new method consisting of preparation of S-carboxymethylglutathione (CMSG) and S-carboxymethylcysteine (CMC), respectively, and subsequent analyses with an amino acid analyzer. CGUA was determined by a coloration method employing an acidic ninhydrin reagent. Total cysteine contents in liver, kidney and plasma rapidly increased to 2.3, 2.7 and 6.5 times the levels of the controls, respectively, after CGUA administration at a dose of 5 mmol/kg of body weight. Total glutathione content did not change significantly in the liver or blood except for the kidney with a significant increase during the first 1-h period after administration. CGUA content increased markedly in these tissues, especially in the kidney, and 30% of administered CGUA was excreted in urine within 2h. These results indicate that CGUA is converted into cysteine in vivo, suggesting the usefulness of this compound for protection of the kidney and the liver.</p>
キーワード cysteine glutathione S-carboxymethylglutathione S-carboxymethylcysteine cysteineglucuronic acied
Amo Type Article
発行日 1995-02
出版物タイトル Acta Medica Okayama
49巻
1号
出版者 Okayama University Medical School
開始ページ 35
終了ページ 42
ISSN 0386-300X
NCID AA00508441
資料タイプ 学術雑誌論文
言語 English
論文のバージョン publisher
査読 有り
PubMed ID 7762408
Web of Sience KeyUT A1995QK32500006