QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Tsai, C.-W. Articles by Lii, C.-K. Search for Related Content PubMed PubMed Citation Articles by Tsai, C.-W. Articles by Lii, C.-K.

---

Nutrient-Gene Interactions

Garlic Organosulfur Compounds Upregulate the Expression of the Class of Glutathione S-Transferase in Rat Primary Hepatocytes¹

Chia-Wen Tsai, Jaw-Ji Yang^*, Haw-Wen Chen, Lee-Yan Sheen and Chong-Kuei Lii²

Department of Nutrition, Chung Shan Medical University, Taichung 402, Taiwan; ^* School of Dentistry, Chung Shan Medical University, Taichung 402, Taiwan; and Graduate Institute of Food Science and Technology, National Taiwan University, Taipei 106, Taiwan

²To whom correspondence should be addressed. E-mail: cklii{at}csmu.edu.tw.

The chemopreventive property of garlic is related in part to its induction of phase II detoxification enzymes. In the present study, we investigated the modulatory effect of 3 garlic organosulfur compounds, i.e., diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), which differ in their number of sulfur atoms, on the gene expression of the class of glutathione S-transferase (GSTP). Hepatocytes isolated from male Sprague-Dawley rats were cultured with 50–200 µmol/L of DAS, DADS, or DATS for 24 h. DADS and DATS increased GST activity toward ethacrynic acid by 40 and 66%, respectively (P < 0.05). Moreover, both garlic allyl sulfides dose dependently induced GSTP mRNA and protein expression. DATS increased the protein level more than DADS (P < 0.05). In contrast, DAS did not affect the activity or the protein or mRNA levels of this phase II drug-metabolizing enzyme. In Clone 9 liver cells, the pTA-luciferase reporter assay showed that luciferase activity in DADS- and DATS-treated cells was 2.8- and 3.9-fold higher than that in control cells, respectively (P < 0.05). Again, luciferase activity was not affected by treatment with DAS. Deletion of –2.7 to –2.6 kb in the GSTP promoter region, which contains the GSTP enhancer (GPE) I element, abolished the upregulation of GSTP transcription by DADS and DATS. Deletion of GPE II, however, did not affect the induction of reporter activity. In conclusion, the effectiveness of 3 garlic allyl sulfides on GSTP expression was related to the number of sulfur atoms in the molecules, and GPE I was responsible for this upregulation.

KEY WORDS: • garlic organosulfur compounds • class of glutathione S-transferase • gene expression • hepatocytes • rats

This article has been cited by other articles:

				Y.-P. Lei, H.-W. Chen, L.-Y. Sheen, and C.-K. Lii Diallyl Disulfide and Diallyl Trisulfide Suppress Oxidized LDL-Induced Vascular Cell Adhesion Molecule and E-Selectin Expression through Protein Kinase A- and B-Dependent Signaling Pathways J. Nutr., June 1, 2008; 138(6): 996 - 1003. [Abstract] [Full Text] [PDF]