Organic Hydroperoxide-Induced Activation of Liver Microsomal Glutathione S-Transferase of Rats In Vitro

The Japanese Journal of Pharmacology

Yoko Aniya¹  Ai Daido¹ 

[1] Laboratory of Physiology and Pharmacology, School of Health Sciences, Faculty of Medicine, University of the Ryukyus

关键词: Glutathione transferase (liver microsome);    t-Butyl hydroperoxide;    Cumene hydroperoxide;    Linoleic acid hydroperoxide;    Enzyme activation;   

DOI  :  10.1254/jjp.62.9

学科分类：药理学

来源: Nihon Yakuri Gakkai Henshuubu / Japanese Pharmacological Society

【 摘 要 】

References(30)Cited-By(4)The effect of t-butyl hydroperoxide (t-BuOOH), cumene hydroperoxide (CuOOH) or linoleic acid hydroperoxide (linoleic-OOH) on liver microsomal glutathione S-transferase of rats was studied in vitro. When microsomes were incubated with either 100 μM t-BuOOH or 25 μM CuOOH, glutathione S-transferase activity was increased 1.5-fold; activity was further increased to 2.2-fold in the presence of small amounts of glutathione. The same amounts of dithiothreitol or cysteine did not enhance the t-BuOOH or CuOOH-induced increase in transferase activity. The transferase activity was also increased 1.4-fold by 10 μM linoleic-OOH plus 1 M glutathione. The increase in microsomal glutathione S-transferase activity after treatment of microsomes with t-BuOOH in the presence of glutathione was completely reversed by addition of dithiothreitol, whereas the activation of the transferase caused by t-BuOOH in the absence of glutathione was not reversed. Although microsomal glutathione S-transferase also possesses glutathione peroxidase activity, only transferase activity was increased by t-BuOOH in either the presence or absence of glutathione. These data indicate that microsomal glutathione S-transferase is activated by organic hydroperoxides in either the absence or presence of small amounts of glutathione, suggesting an activation of the transferase by thiol oxidation of the cysteine residue.

【 授权许可】

Unknown