• YAKHAK HOEJI
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• v.54 no.6
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• pp.481-487
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• 2010

The proteasome plays a major role in the degradation of abnormal proteins within the cell. Therefore, repressed proteasome function is accepted as one of factors contributing the pathogenesis of multiple degenerative diseases. In the present study, we have observed that xanthohumol C, which is one of prenylated flavonoids from hops, increases the expression of the proteasome subunits through the Nrf2 pathway. Treatment of murine renal epithelial TCMK-1 cells with xanthohumol C and its methoxymethoxy-derivative elevated the expression of the Antioxidant Response Element (ARE)-driven reporter gene, as well as Nrf2-target genes including NAD(P)H: quinoneoxidoreductaes 1 (Nqo1). Transcript levels for the catalytic subunits of the proteasome Psmb5 and Psmb6 were increased by these compounds. The activation of the psmb5 promoter by xanthohumol C was abolished when the ARE in this promoter was mutated, indicating that proteasome induction was mediated by the Nrf2-ARE pathway. These results suggest that xanthohumol compounds from hops have a potential benefit on various oxidative stress-associated human diseases through the induction of the proteasome.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.422-429
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• 2009

Invasion and metastasis is the main cause of cancer mortality. Angiogenesis is a prerequisite for the tumor growth and metastasis. Matrix metalloproteinases (MMPs) are the key enzymes playing in the invasive growth and metastasis of cancer as well as angiogenesis. Xanthohumol, a prenylated chalcone of the Hop plant (Humulus lupulus L), has been reported to suppress cancer invasion and angiogenesis. In the present study, we investigated the antiinvasive effects of xanthohumol (1) and its synthetic derivatives, 4'-O-methylxanthohumol SEM ether (2), xanthohumol C (3), and xanthohumol C MOM ether (4) in relation to MMP expression in HT-1080 human fibrosarcoma cells. The compound 1 and its derivative, 3 and 4, significantly inhibited serum-induced HT-1080 cell invasion, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-enhanced activity and expression level of MMP-2 and MMP-9 in a concentration-dependant manner. In addition, they inhibited TPA-enhanced expression of MT1-MMP with relatively weak inhibition in tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 level. The compound 1 significantly decreased the cell viability, whereas the derivatives, 2 and 3 showed no cytotoxicity, and compound 4 showed slight cytotoxicity in the cells. Furthermore, in a chick chorioallantoic membrane (CAM) assay, the derivatives 3 and 4 dose-dependently suppressed vascular endothelial growth factor (VEGF)-induced angiogenesis, which is similar to that of compound 1. Taken together, the results indicate that compounds 3 and 4 may be valuable anti-angiogenic agents in the treatment of chronic diseases such as cancer and inflammation working through suppression of MMP-2 and MMP-9.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.35-36
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• 2001

Nutrition influences cancer incidence and offers a variety of preventive dietary factors including non-nutritive plant metabolites. To identify novel potential chemopreventive agents, we have set up cell- and enzyme-based in vitro marker systems relevant for prevention of carcinogenesis in vivo. This experimental approach led to the identification of Xanthohumol (Xn), a prenylated chalcone from hop (Humulus lupulus L.) as a most promising broad-spectrum chemopreventive agent.(omitted)