著者

Makoto Ozaki Motoshi Shimotsuma Takefumi Kuranaga Hideaki Kakeya Tsunehisa Hirose

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

pp.c23-00439, (Released:2023-08-24)

参考文献数

34

被引用文献数

1

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D-Amino acids, which are present in small amounts in living organisms, are responsible for a variety of physiological functions. Some bioactive/biomolecular peptides also contain D-amino acids in their sequences; such peptides express different functions than peptides composed only of L-form amino acids. Among the 20 amino acids that make up proteins, threonine (Thr) and isoleucine (Ile) have two chiral carbons and thus have two enantiomers and diastereomers. These stereoisomers have been previously analyzed through high-performance liquid chromatography using chiral columns or chiral resolution labeling reagents. However, the separation and identification of these stereoisomers are highly laborious and complicated. Herein, we propose an analytical method for the separation and identification of Ile stereoisomers through liquid chromatography–mass spectrometry using an original chiral resolution labeling reagent, 1-fluoro-2,4-dinitrophenyl-5-L-valine-N,N-dimethylethylenediamine-amide (L-FDVDA) and a PBr column packed with pentabromobenzyl-modified silica gel. Twenty DL-amino acids including Thr stereoisomers (41 amino acids including glycine) were separated and identified using C18 column. Ile stereoisomers could be separated using not a C18 column but a PBr column. Additionally, we showed that peptides containing Thr and Ile stereoisomers can be accurately detected through labeling with L-FDVDA.

著者

Hiroki Sasaki Yoichi Sunagawa Kenji Takahashi Atsushi Imaizumi Hiroyuki Fukuda Tadashi Hashimoto Hiromichi Wada Yasufumi Katanasaka Hideaki Kakeya Masatoshi Fujita Koji Hasegawa Tatsuya Morimoto

出版者

The Pharmaceutical Society of Japan

雑誌

Biological and Pharmaceutical Bulletin (ISSN:09186158)

巻号頁・発行日

vol.34, no.5, pp.660-665, 2011-05-01 (Released:2011-05-01)

参考文献数

26

被引用文献数

68 325

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Curcumin is a polyphenol that is commonly used for its perceived health benefits. However, the absorption efficacy of curcumin is too low to exhibit beneficial effects. We have successfully developed a highly absorptive curcumin dispersed with colloidal nano-particles, and named it THERACURMIN. The absorption efficacy of THERACURMIN was investigated and compared with that of curcumin powder. The area under the blood concentration–time curve (AUC) after the oral administration of THERACURMIN was found to be more than 40-fold higher than that of curcumin powder in rats. Then, healthy human volunteers were administered orally 30 mg of THERACURMIN or curcumin powder. The AUC of THERACURMIN was 27-fold higher than that of curcumin powder. In addition, THERACURMIN exhibited an inhibitory action against alcohol intoxication after drinking in humans, as evidenced by the reduced acetaldehyde concentration of the blood. These findings demonstrate that THERACURMIN shows a much higher bioavailability than currently available preparations. Thus, THERACURMIN may be useful to exert clinical benefits in humans at a lower dosage.

著者

Hitomi Ozawa Atsushi Imaizumi Yoshihiko Sumi Tadashi Hashimoto Masashi Kanai Yuji Makino Takanori Tsuda Nobuaki Takahashi Hideaki Kakeya

出版者

公益社団法人日本薬学会

雑誌

Biological and Pharmaceutical Bulletin (ISSN:09186158)

巻号頁・発行日

vol.40, no.9, pp.1515-1524, 2017-09-01 (Released:2017-09-01)

参考文献数

50

被引用文献数

35

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Curcumin, a polyphenol derived from the rhizome of the naturally occurring plant Curcuma longa, has various pharmacological actions such as antioxidant and anti-inflammatory effects. In this paper, we evaluated the role of its internal metabolite, curcumin β-D-glucuronide (curcumin monoglucuronide, CMG), by investigating curcumin kinetics and metabolism in the blood. Firstly, we orally administered highly bioavailable curcumin to rats to elucidate its kinetics, and observed not only the free-form of curcumin, but also, curcumin in a conjugated form, within the portal vein. We confirmed that curcumin is conjugated when it passes through the intestinal wall. CMG, one of the metabolites, was then orally administered to rats. Despite its high aqueous solubility compared to free-form curcumin, it was not well absorbed. In addition, CMG was injected intravenously into rats in order to assess its metabolic behavior in the blood. Interestingly, high levels of free-form curcumin, thought to be sufficiently high to be pharmacologically active, were observed. The in vivo antitumor effects of CMG following intravenous injection were then evaluated in tumor-bearing mice with the HCT116 human colon cancer cell line. The tumor volume within the CMG group was significantly less than that of the control group. Moreover, there was no significant loss of body weight in the CMG group compared to the control group. These results suggest that CMG could be used as an anticancer agent without the serious side effects that most anticancer agents have.