Planta Med 2014; 80(01): 97-104
DOI: 10.1055/s-0033-1351097
Biological Screening
Original Papers
Georg Thieme Verlag KG Stuttgart · New York

Screening of Natural Compounds as Activators of the Keap1-Nrf2 Pathway

Kai C. Wu
1   Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS, USA
,
Peter R. McDonald
2   High-Throughput Screening Core Facility, Structural Biology Center, University of Kansas, Lawrence, KS, USA
,
Jie Liu
3   Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS, USA
,
Curtis D. Klaassen
3   Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS, USA
› Author Affiliations
Further Information

Publication History

received 20 July 2012
revised 15 October 2013

accepted 24 October 2013

Publication Date:
05 December 2013 (online)

Abstract

Nuclear factor erythroid 2-related factor 2 is a master regulator that promotes transcription of cytoprotective genes in response to oxidative/electrophilic stress. A large number of natural dietary compounds are thought to protect against oxidative stress, and a few have been reported to induce genes involved in antioxidant defense through activating nuclear factor erythroid 2-related factor 2. Therefore, a library of 54 natural compounds were collected to determine whether they are nuclear factor erythroid 2-related factor 2 activators and to compare their efficacy and potency to activate nuclear factor erythroid 2-related factor 2. The assay utilized AREc32 cells that contain a luciferase gene under the control of antioxidant response element promoters. Each natural compound was tested at 13 concentrations between 0.02 and 30 µM. Known nuclear factor erythroid 2-related factor 2 activators tert-butylhydroquinone and 2-cyano-3,12-dioxooleana-1,9-diene-28-imidazolide were used as positive controls in parallel with the natural compounds. Among the 54 tested natural compounds, andrographolide had the highest efficacy, followed by trans-chalcone, sulforaphane, curcumin, flavone, kahweol, and carnosol, all of which had better efficacy than tert-butylhydroquinone. Among the compounds tested, 2-cyano-3,12-dioxooleana-1,9-diene-28-imidazolide was the most potent, having an EC50 of 0.41 µM. Seven of the natural compounds, namely andrographolide, trans-chalcone, sulforaphane, curcumin, flavone, kahweol, and cafestol had lower EC50 values than tert-butylhydroquinone but higher than 2-cyano-3,12-dioxooleana-1,9-diene-28-imidazolide. The present study provides insights into which natural compounds activate the Keap1-nuclear factor erythroid 2-related factor 2 pathway and thus might be useful for detoxifying oxidative/electrophilic stress.

Supporting Information

 
  • References

  • 1 Cullinan SB, Gordan JD, Jin J, Harper JW, Diehl JA. The Keap1-BTB protein is an adaptor that bridges Nrf2 to a Cul3-based E3 ligase: oxidative stress sensing by a Cul3-Keap1 ligase. Mol Cell Biol 2004; 24: 8477-8486
  • 2 Kensler TW, Wakabayashi N, Biswal S. Cell survival responses to environmental stresses via the Keap1-Nrf2-ARE pathway. Annu Rev Pharmacol Toxicol 2007; 47: 89-116
  • 3 Wang LJ, Zhou X, Wang W, Tang F, Qi CL, Yang X, Wu S, Lin YQ, Wang JT, Geng JG. Andrographolide inhibits oral squamous cell carcinogenesis through NF-kappaB inactivation. J Dent Res 2011; 90: 1246-1252
  • 4 Wu KC, Cui JY, Klaassen CD. Effect of graded Nrf2 activation on phase-I and -II drug metabolizing enzymes and transporters in mouse liver. PLoS One 2012; 7: e39006
  • 5 Reisman SA, Aleksunes LM, Klaassen CD. Oleanolic acid activates Nrf2 and protects from acetaminophen hepatotoxicity via Nrf2-dependent and Nrf2-independent processes. Biochem Pharmacol 2009; 77: 1273-1282
  • 6 Balstad TR, Carlsen H, Myhrstad MC, Kolberg M, Reiersen H, Gilen L, Ebihara K, Paur I, Blomhoff R. Coffee, broccoli and spices are strong inducers of electrophile response element-dependent transcription in vitro and in vivo – studies in electrophile response element transgenic mice. Mol Nutr Food Res 2011; 55: 185-197
  • 7 Surh YJ, Kundu JK, Na HK. Nrf2 as a master redox switch in turning on the cellular signaling involved in the induction of cytoprotective genes by some chemopreventive phytochemicals. Planta Med 2008; 74: 1526-1539
  • 8 Tanigawa S, Fujii M, Hou DX. Action of Nrf2 and Keap1 in ARE-mediated NQO1 expression by quercetin. Free Radic Biol Med 2007; 42: 1690-1703
  • 9 Martin D, Rojo AI, Salinas M, Diaz R, Gallardo G, Alam J, Ruiz de Galarreta CM, Cuadrado A. Regulation of heme oxygenase-1 expression through the phosphatidylinositol 3-kinase/Akt pathway and the Nrf2 transcription factor in response to the antioxidant phytochemical carnosol. J Biol Chem 2004; 279: 8919-8929
  • 10 Zhang DD, Hannink M. Distinct cysteine residues in Keap1 are required for Keap1-dependent ubiquitination of Nrf2 and for stabilization of Nrf2 by chemopreventive agents and oxidative stress. Mol Cell Biol 2003; 23: 8137-8151
  • 11 Zhang DD, Lo SC, Sun Z, Habib GM, Lieberman MW, Hannink M. Ubiquitination of Keap1, a BTB-Kelch substrate adaptor protein for Cul3, targets Keap1 for degradation by a proteasome-independent pathway. J Biol Chem 2005; 280: 30091-30099
  • 12 Yan D, Dong J, Sulik KK, Chen SY. Induction of the Nrf2-driven antioxidant response by tert-butylhydroquinone prevents ethanol-induced apoptosis in cranial neural crest cells. Biochem Pharmacol 2010; 80: 144-149
  • 13 Koh K, Cha Y, Kim S, Kim J. tBHQ inhibits LPS-induced microglial activation via Nrf2-mediated suppression of p 38 phosphorylation. Biochem Biophys Res Commun 2009; 380: 449-453
  • 14 Shih AY, Imbeault S, Barakauskas V, Erb H, Jiang L, Li P, Murphy TH. Induction of the Nrf2-driven antioxidant response confers neuroprotection during mitochondrial stress in vivo . J Biol Chem 2005; 280: 22925-22936
  • 15 Liby K, Hock T, Yore MM, Suh N, Place AE, Risingsong R, Williams CR, Royce DB, Honda T, Honda Y, Gribble GW, Hill-Kapturczak N, Agarwal A, Sporn MB. The synthetic triterpenoids, CDDO and CDDO-imidazolide, are potent inducers of heme oxygenase-1 and Nrf2/ARE signaling. Cancer Res 2005; 65: 4789-4798
  • 16 Reisman SA, Buckley DB, Tanaka Y, Klaassen CD. CDDO-Im protects from acetaminophen hepatotoxicity through induction of Nrf2-dependent genes. Toxicol Appl Pharmacol 2009; 236: 109-114
  • 17 Thimmulappa RK, Mai KH, Srisuma S, Kensler TW, Yamamoto M, Biswal S. Identification of Nrf2-regulated genes induced by the chemopreventive agent sulforaphane by oligonucleotide microarray. Cancer Res 2002; 62: 5196-5203
  • 18 Mishra K, Dash AP, Dey N. Andrographolide: a novel antimalarial diterpene lactone compound from Andrographis paniculata and its interaction with curcumin and artesunate. J Trop Med 2011; 2011: 579518
  • 19 Lu WJ, Lee JJ, Chou DS, Jayakumar T, Fong TH, Hsiao G, Sheu JR. A novel role of andrographolide, an NF-kappa B inhibitor, on inhibition of platelet activation: the pivotal mechanisms of endothelial nitric oxide synthase/cyclic GMP. J Mol Med (Berl) 2011; 89: 1261-1273
  • 20 Liu C, Nadiminty N, Tummala R, Chun JY, Lou W, Zhu Y, Sun M, Evans CP, Zhou Q, Gao AC. Andrographolide targets androgen receptor pathway in castration-resistant prostate cancer. Genes Cancer 2011; 2: 151-159
  • 21 Yu AL, Lu CY, Wang TS, Tsai CW, Liu KL, Cheng YP, Chang HC, Lii CK, Chen HW. Induction of heme oxygenase 1 and inhibition of tumor necrosis factor alpha-induced intercellular adhesion molecule expression by andrographolide in EA.hy926 cells. J Agric Food Chem 2010; 58: 7641-7648
  • 22 Cavin C, Holzhaeuser D, Scharf G, Constable A, Huber WW, Schilter B. Cafestol and kahweol, two coffee specific diterpenes with anticarcinogenic activity. Food Chem Toxicol 2002; 40: 1155-1163
  • 23 Higgins LG, Cavin C, Itoh K, Yamamoto M, Hayes JD. Induction of cancer chemopreventive enzymes by coffee is mediated by transcription factor Nrf2. Evidence that the coffee-specific diterpenes cafestol and kahweol confer protection against acrolein. Toxicol Appl Pharmacol 2008; 226: 328-337
  • 24 Takahashi T, Tabuchi T, Tamaki Y, Takikawa Y, Satoh T. Carnosic acid and carnosol inhibit adipocyte differentiation in mouse 3 T3-L1 cells through induction of phase2 enzymes and activation of glutathione metabolism. Biochem Biophys Res Commun 2009; 382: 549-554
  • 25 Woo AY, Waye MM, Tsui SK, Yeung ST, Cheng CH. Andrographolide up-regulates cellular-reduced glutathione level and protects cardiomyocytes against hypoxia/reoxygenation injury. J Pharmacol Exp Ther 2008; 325: 226-235
  • 26 White EL, Ross LJ, Schmid SM, Kelloff GJ, Steele VE, Hill DL. Screening of potential cancer preventing chemicals for induction of glutathione in rat liver cells. Oncol Rep 1998; 5: 507-512
  • 27 Kumar V, Kumar S, Hassan M, Wu H, Thimmulappa RK, Kumar A, Sharma SK, Parmar VS, Biswal S, Malhotra SV. Novel chalcone derivatives as potent Nrf2 activators in mice and human lung epithelial cells. J Med Chem 2011; 54: 4147-4159
  • 28 Balogun E, Hoque M, Gong P, Killeen E, Green CJ, Foresti R, Alam J, Motterlini R. Curcumin activates the haem oxygenase-1 gene via regulation of Nrf2 and the antioxidant-responsive element. Biochem J 2003; 371: 887-895
  • 29 Hess A, Wijayanti N, Neuschafer-Rube AP, Katz N, Kietzmann T, Immenschuh S. Phorbol ester-dependent activation of peroxiredoxin I gene expression via a protein kinase C, Ras, p 38 mitogen-activated protein kinase signaling pathway. J Biol Chem 2003; 278: 45419-45434
  • 30 Lee Y, Shin DH, Kim JH, Hong S, Choi D, Kim YJ, Kwak MK, Jung Y. Caffeic acid phenethyl ester-mediated Nrf2 activation and IkappaB kinase inhibition are involved in NFkappaB inhibitory effect: structural analysis for NFkappaB inhibition. Eur J Pharmacol 2010; 643: 21-28
  • 31 Saracino MR, Lampe JW. Phytochemical regulation of UDP-glucuronosyltransferases: implications for cancer prevention. Nutr Cancer 2007; 59: 121-141
  • 32 Dinkova-Kostova AT. Phytochemicals as protectors against ultraviolet radiation: versatility of effects and mechanisms. Planta Med 2008; 74: 1548-1559
  • 33 Wruck CJ, Claussen M, Fuhrmann G, Römer L, Schulz A, Pufe T, Waetzig V, Peipp M, Herdegen T, Götz ME. Luteolin protects rat PC12 and C6 cells against MPP+ induced toxicity via an ERK dependent Keap1-Nrf2-ARE pathway. J Neural Transm Suppl 2007; 72: 57-67
  • 34 Tsai PY, Ka SM, Chang JM, Chen HC, Shui HA, Li CY, Hua KF, Chang WL, Huang JJ, Yang SS, Chen A. Epigallocatechin-3-gallate prevents lupus nephritis development in mice via enhancing the Nrf2 antioxidant pathway and inhibiting NLRP3 inflammasome activation. Free Radic Biol Med 2011; 51: 744-754
  • 35 Miyamoto N, Izumi H, Miyamoto R, Kondo H, Tawara A, Sasaguri Y, Kohno K. Quercetin induces the expression of peroxiredoxins 3 and 5 via the Nrf2/NRF1 transcription pathway. Invest Ophthalmol Vis Sci 2011; 52: 1055-1063
  • 36 Kode A, Rajendrasozhan S, Caito S, Yang SR, Megson IL, Rahman I. Resveratrol induces glutathione synthesis by activation of Nrf2 and protects against cigarette smoke-mediated oxidative stress in human lung epithelial cells. Am J Physiol Lung Cell Mol Physiol 2008; 294: L478-L488
  • 37 Rubiolo JA, Mithieux G, Vega FV. Resveratrol protects primary rat hepatocytes against oxidative stress damage: activation of the Nrf2 transcription factor and augmented activities of antioxidant enzymes. Eur J Pharmacol 2008; 591: 66-72
  • 38 Ungvari Z, Bagi Z, Feher A, Recchia FA, Sonntag WE, Pearson K, de Cabo R, Csiszar A. Resveratrol confers endothelial protection via activation of the antioxidant transcription factor Nrf2. Am J Physiol Heart Circ Physiol 2010; 299: H18-H24
  • 39 Luo Y, Eggler AL, Liu D, Liu G, Mesecar AD, van Breemen RB. Sites of alkylation of human Keap1 by natural chemoprevention agents. J Am Soc Mass Spectrom 2007; 18: 2226-2232
  • 40 Feng J, Zhang P, Chen X, He G. PI3K and ERK/Nrf2 pathways are involved in oleanolic acid-induced heme oxygenase-1 expression in rat vascular smooth muscle cells. J Cell Biochem 2011; 112: 1524-1531
  • 41 Roth M, Araya JJ, Timmermann BN, Hagenbuch B. Isolation of modulators of the liver-specific organic anion-transporting polypeptides (OATPs) 1B1 and 1B3 from Rollinia emarginata Schlecht (Annonaceae). J Pharmacol Exp Ther 2011; 339: 624-632
  • 42 Natsch A, Emter R. Skin sensitizers induce antioxidant response element dependent genes: application to the in vitro testing of the sensitization potential of chemicals. Toxicol Sci 2008; 102: 110-119