Abstract |
Alpha-hederin, a triterpenoid saponin, has been reported to induce hepatic metallothionein (MT). However, the mechanism underlying its effects is unknown. This study investigated the effects of alpha-hederin on the regulation of MT expression in an in vitro model using the murine hepatoma cell line, Hepa-1c1c7, and the murine macrophage cell line, RAW 264.7. Alpha-hederin that was added directly to Hepa-1c1c7 cells had no effect on MT induction. However, MT and its mRNA levels increased markedly when the Hepa-1c1c7 cells were cultured with the alpha-hederin-treated, conditioned medium from the RAW 264.7 cells. Co-treating the RAW 264.7 cells with alpha-hederin and pentoxifylline, a TNF-alpha synthesis inhibitor, resulted in decreased effects of alpha-hederin on MT induction. In the alpha-hederin-exposed RAW 264.7 cell cultures, production and mRNA levels of TNF-alpha and IL-6 were increased. Accordingly, it was found that the MT induction activity was inhibited when antibodies to TNF-alpha and/or IL-6 were added to the alpha-hederin-treated, conditioned medium from the RAW 264.7 cells. These results suggest that the upregulation of MT expression by alpha-hederin is mediated by TNF-alpha and IL-6.
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Authors | Ji Young Kim, Chul Yung Choi, Hye Gwang Jeong |
Journal | Planta medica
(Planta Med)
Vol. 71
Issue 8
Pg. 743-7
(Aug 2005)
ISSN: 0032-0943 [Print] Germany |
PMID | 16142639
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Cytokines
- Interleukin-6
- RNA, Messenger
- Saponins
- Tumor Necrosis Factor-alpha
- beta-hederin
- Oleanolic Acid
- Metallothionein
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Topics |
- Animals
- Cell Line, Tumor
(drug effects)
- Cell Survival
- Cytokines
(biosynthesis)
- Dose-Response Relationship, Drug
- Interleukin-6
(biosynthesis)
- Macrophages
(drug effects, metabolism)
- Metallothionein
(drug effects, metabolism)
- Mice
- Oleanolic Acid
(administration & dosage, analogs & derivatives, pharmacology, therapeutic use)
- Phytotherapy
- Plants, Medicinal
- RNA, Messenger
(metabolism)
- Reverse Transcriptase Polymerase Chain Reaction
- Saponins
(administration & dosage, pharmacology, therapeutic use)
- Tumor Necrosis Factor-alpha
(biosynthesis)
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