title: (-)-Epigallocatechin-3-gallate stimulates both AMP-activated protein kinase and nuclear factor-kappa B signaling pathways.
abstract: We previously reported that (-)-epigallocatechin-3-gallate (EGCG) increased the level of SHARP-1 mRNA via a phosphoinositide 3-kinase/atypical protein kinase C lambda signaling pathway in rat H4IIE hepatoma cells. In the present study, we investigated other signaling pathway(s). Treating with either compound-C, BAY11-7082, or both, partially blocked the up-regulation of the SHARP-1 gene by EGCG. This suggests that AMP-activated protein kinase (AMPK)- and nuclear factor-kappa B (NF-κB)-signaling pathways were additively involved in the induction mediated by EGCG. Indeed, an AMPK activator induced a level of SHARP-1 mRNA. Although actinomycin D partially blocked the EGCG-induction of that SHARP-1 mRNA level, the nucleotide sequence between -1501 and -1 in the rat SHARP-1 gene did not positively respond to EGCG and NF-κB, respectively. Thus, we conclude that EGCG stimulates multiple signaling pathways in the SHARP-1 gene expression at the transcriptional and post-transcriptional levels and that there is no regulatory region susceptible to EGCG and NF-κB in the examined region.
authors.affiliation: Department of Health and Nutritional Science, Faculty of Human Health Science, Matsumoto University, 2095-1 Niimura, Matsumoto, Nagano 390-1295, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Asano
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Takagi
authors.forename: Ayumi
authors.initials: A
authors.lastname: Haneishi
authors.forename: Soichiro
authors.initials: S
authors.lastname: Nakamura
authors.forename: Kazuya
authors.initials: K
authors.lastname: Yamada
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects*; D015854:Up-Regulation / Q000187:drug effects*
chemical_list: D055372:AMP-Activated Protein Kinases; D051792:Basic Helix-Loop-Helix Proteins; D002392:Catechin; D016328:NF-kappa B; C109509:Bhlhe41 protein, rat; C045651:epigallocatechin gallate