3081-62-7Relevant articles and documents
Antidiabetic activity of Zn(II) complexes with a derivative of L-glutamine
Matsumoto, Kinuyo,Yamamoto, Shuhei,Yoshikawa, Yutaka,Doe, Matsumi,Kojima, Yoshitane,Sakurai, Hiromu,Hashimoto, Hiroko,Kajiwara, Naemi M.
, p. 1077 - 1081 (2005)
The insulinomimetic activity of zinc(II) complexes Zn(gln-m)2 and Zn(gln-e)2, respectively, with L-γ-glutamyl-methylamide (gln-m) and -ethylamide (theanine: gln-e), components of green tea, were compared to that of Zn(gln)2 with L-glutamine (gin) in an in vitro study using isolated rodent adipocytes treated with epinephrine in the presence of glucose, expressed as the IC50 value (50% inhibition concentration) of free fatty acids (FFA) released from fat cells. The former were found to have higher inslinomimetic activity than that of the latter. The IC50 values of the former were 0.61 and 0.56, respectively. Then, the anti-diabetic activity of a zinc(II) complex, Zn(gln-e)2, was examined in an in vivo experiment on KK-Aγ mice, model animals of type-2 DM, by the intraperitoneal (ip) injection of 3-4 mg Zn/kg b.w./day for 13 days. The blood-glucose level of a group treated with a Zn complex, Zn(gln-e)2, decreased significantly after 13 days compared to those of non-treated and gln-e treated groups. The serum concentrations of triglyceride (TG) and HbA1C decreased significantly in Zn(gln-e) 2 treated KK-Aγ mice compared to those of the gln-e treated group, respectively. Furthermore, the improvement in glucose tolerance was confirmed by an oral glucose tolerance test.
Peptide Tyrosinase Activators
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, (2015/06/10)
Peptides that increase melanin synthesis are provided. These peptides include pentapeptides YSSWY, YRSRK, and their variants. The peptides may activate the enzymatic activity of tyrosinase to increase melanin synthesis. The pharmaceutical, cosmetic, and other compositions including the peptides are also provided. The methods of increasing melanin production in epidermis of a subject are provided where the methods include administering compositions comprising an amount of one or more peptides effective to increase the melanin production. The methods also include treating vitiligo or other hypopigmentation disorders with compositions including one or more peptides.
A novel catalytic ability of γ-glutamylcysteine synthetase of Escherichia coli and its application in theanine production
Miyake, Koichiro,Kakita, Shingo
experimental part, p. 2677 - 2683 (2010/09/11)
γ-Glutamylcysteine synthetase (γGCS, EC 6.3.2.2) catalyzes the formation of γ-glutamylcysteine from L-glutamic acid (Glu) and L-cysteine (Cys) in an ATP-dependent manner. While γGCS can use various amino acids as substrate, little is known about whether it can use non-amino acid compounds in place of Cys. We determined that γGCS from Escherichia coli has the ability to combine Glu and amines to form γ-glutamylamides. The reaction rate depended on the length of the methylene chain of the amines in the following order: n-propylamine > butylamine > ethylamine methylamine. The optimal pH for the reaction was narrower and more alkaline than for the reaction with an amino acid. The newly found catalytic ability of γGCS was used in the production of theanine (γ-glutamylethylamine). The resting cells of E. coli expressing γGCS, in which ATP was regenerated through glycolysis, synthesized 12.1 mm theanine (18 h) from 429 mm ethylamine.
