Bupleurum chinense Roots: a Bioactivity-Guided Approach toward Saponin-Type NF-κB Inhibitors

Abstract

The roots of Bupleurum chinense have a long history in traditional medicine to treat infectious diseases and inflammatory disorders. Two major compounds, saikosaponins A and D, were reported to exert potent anti-inflammatory activity by inhibiting NF-κB. In the present study, we isolated new saikosaponin analogues from the roots of B. chinese interfering with NF-κB activity in vitro. The methanol-soluble fraction of the dichloromethane extract of Radix Bupleuri was subjected to activity-guided isolation yielding 18 compounds, including triterpenoids and polyacetylenes. Their structures were determined by spectroscopic methods as saikogenin D (1), prosaikogenin D (2), saikosaponins B₂ (3), W (4), B₁ (5), Y (6), D (7), A (8), E (9), B₄ (10), B₃ (11), and T (12), saikodiyne A (13), D (14), E (15) and F (16), falcarindiol (17), and 1-linoleoyl-sn-glycero-3-phosphorylcholine (18). Among them, 4, 15, and 16 are new compounds, whereas 6, previously described as a semi-synthetic compound, is isolated from a natural source for the first time, and 13–17 are the first reports of polyacetylenes from this plant. Nine saponins/triterpenoids were tested for inhibition of NF-κB signaling in a cell-based NF-κB-dependent luciferase reporter gene model in vitro. Five of them (1, 2, 4, 6, and 8) showed strong (> 50%, at 30 µM) NF-κB inhibition, but also varying degrees of cytotoxicity, with compounds 1 and 4 (showing no significant cytotoxicity) presenting IC₅₀ values of 14.0 µM and 14.1 µM in the cell-based assay, respectively.

Key words

Bupleurum chinense - Apiaceae - NF-κB - saponin - polyacetylene - lysophosphatidylcholine

^* These authors contributed equally to this work.

• References

• 1 Baldwin AS. The transcription factor NF-κB and human disease. J Clin Invest 2001; 107: 3-6
• 2 Karin M. Nuclear factor-κB in cancer development and progression. Nature 2006; 441: 431-436
• 3 Wang CY, Cusack JC, Liu R, Baldwin AS. Control of inducible chemoresistance: enhanced anti-tumor therapy through increased apoptosis by inhibition of NF-κB. Nat Med 1999; 5: 412-417
• 4 Salminen A, Hyttinen JMT, Kaarniranta K. AMP-activated protein kinase inhibits NF-κB signaling and inflammation: impact on healthspan and lifespan. J Mol Med 2011; 89: 667-676
• 5 Tornatore L, Thotakura AK, Bennett J, Moretti M, Franzoso G. The nuclear factor kappa B signaling pathway: integrating metabolism with inflammation. Trends Cell Biol 2012; 22: 557-566
• 6 Gareus R, Kotsaki E, Xanthoulea S, van der Made I, Gijbels MJJ, Kardakaris R, Polykratis A, Kollias G, de Winther MPJ, Pasparakis M. Endothelial cell-specific NF-κB inhibition protects mice from atherosclerosis. Cell Metab 2008; 8: 372-383
• 7 Gilmore TD, Garbati MR. Inhibition of NF-κB signaling as a strategy in disease therapy. Curr Top Microbiol Immunol 2011; 349: 245-263
• 8 Bremner P, Heinrich M. Natural products as targeted modulators of the nuclear factor-kappaB pathway. J Pharm Pharmacol 2002; 54: 453-472
• 9 Salminen A, Lehtonen M, Suuronen T, Kaarniranta K, Huuskonen J. Terpenoids: natural inhibitors of NF-kappaB signaling with anti-inflammatory and anticancer potential. Cell Mol Life Sci 2008; 65: 2979-2999
• 10 Fakhrudin N, Waltenberger B, Cabaravdic M, Atanasov AG, Malainer C, Schachner D, Heiss EH, Liu R, Noha SM, Grzywacz AM, Mihaly-Bison J, Awad EM, Schuster D, Breuss JM, Rollinger JM, Bochkov V, Stuppner H, Dirsch VM. Identification of plumericin as a potent new inhibitor of the NF-κB pathway with anti-inflammatory activity in vitro and in vivo . Br J Pharmacol 2014; 171: 1676-1686
• 11 Tran TVA, Malainer C, Schwaiger S, Atanasov AG, Heiss EH, Dirsch VM, Stuppner H. NF-κB inhibitors from Eurycoma longifolia . J Nat Prod 2014; 77: 483-488
• 12 Zhao GP, Dai S, Chen RS. eds. Dictionary of Traditional Chinese Medicine. 2nd ed.. ed. Shanghai: Shanghai Scientific and Technical Publishers; 2006
• 13 Ashour ML, Wink M. Genus Bupleurum: a review of its phytochemistry, pharmacology and modes of action. J Pharm Pharmacol 2011; 63: 305-321
• 14 Benito PB, Martinez MJA, Sen AMS, Gomez AS, Matellano LF, Contreras SS, Lanza AMD. In vivo and in vitro antiinflammatory activity of saikosaponins. Life Sci 1998; 63: 1147-1156
• 15 Lu XL, He SX, Ren MD, Wang YL, Zhang YX, Liu EQ. Chemopreventive effect of saikosaponin-d on diethylinitrosamine-induced hepatocarcinogenesis: involvement of CCAAT/enhancer binding protein β and cyclooxygenase-2. Mol Med Rep 2012; 5: 637-644
• 16 Lu CN, Yuan ZG, Zhang XL, Yan R, Zhao YQ, Liao M, Chen JX. Saikosaponin a and its epimer saikosaponin d exhibit anti-inflammatory activity by suppressing activation of NF-κB signaling pathway. Int Immunopharmacol 2012; 14: 121-126
• 17 Ishii H, Nakamura M, Seo S, Tori K, Tozyo T, Yoshimura Y. Isolation, characterization, and nuclear magnetic resonance spectra of new saponins from the roots of Bupleurum falcatum L. Chem Pharm Bull 1980; 28: 2367-2373
• 18 Ogihara Y, Nose M. Novel cleavage of the glycosidic bond of saponins in alcoholic alkali metal solution containing a trace of water. J Chem Soc Chem Commun 1986; 1417
• 19 Kobayashi Y, Takeda T, Ogihara Y. New triterpenoid glycosides from the leaves of Bupleurum rotundifolium L. Chem Pharm Bull 1981; 29: 2222-2229
• 20 Shimizu K, Amagaya S, Ogihara Y. New derivatives of saikosaponins. Chem Pharm Bull 1985; 33: 3349-3355
• 21 Liang H, Zhao Y, Qiu H, Huang J, Zhang R. New saikosaponin from Bupleurum chinese DC. Acta Pharm Sin 1998; 33: 37-41
• 22 Shimaoka A, Seo S, Minato H. Saponins isolated from Bupleurum falcatum L.; components of saikosaponin b. J Chem Soc Perkin 1 1975; 2043-2048
• 23 Shimizu K, Amagaya S, Ogihara Y. Structural transformation of saikosaponins by gastric juice and intestinal flora. J Pharmacobiodyn 1985; 8: 718-725
• 24 Xu L, Tian JX, Song R, Liu GQ, Tian Y, Zhang ZJ. LC-MS/MS determination and comparison of saikosaponin a,b2,c,d in crude and processed Radix Bupleuri by vinegar. J China Pharm Univ 2012; 43: 334-340
• 25 Min J, Lee YJ, Kim YA, Park HS, Han SY, Jhon GJ, Choi W. Lysophosphatidylcholine derived from deer antler extract suppresses hyphal transition in Candida albicans through MAP kinase pathway. Biochim Biophys Acta 2001; 1531: 77-89
• 26 Houjou T, Yamatani K, Nakanishi H, Imagawa M, Shimizu T, Taguchi R. Rapid and selective identification of molecular species in phosphatidylcholine and sphingomyelin by conditional neutral loss scanning and MS3. Rapid Commun Mass Spectrom 2004; 18: 3123-3130
• 27 Morita M, Nakajima K, Ikeya Y, Mitsuhashi H. Polyacetylenes from roots of Bupleurum falcatum . Phytochemistry 1991; 30: 1543-1545
• 28 OʼNeill T, Johnson JA, Webster D, Gray CA. The Canadian medicinal plant Heracleum maximum contains antimycobacterial diynes and furanocoumarins. J Ethnopharmacol 2013; 147: 232-237
• 29 Ohta T, Uwai K, Kikuchi R, Nozoe S, Oshima Y, Sasakl K, Yoshizaki F. Absolute stereochemistry of cicutoxin and related toxic polyacetylenic alcohols from Cicuta virosa . Tetrahedron 1999; 55: 12087-12098
• 30 Fiandanese V, Bottalico D, Cardellicchio C, Marchese G, Punzi A. Stereoselective total synthesis of (S)-Virol C and (S)-1-dehydroxyvirol A. Tetrahedron 2005; 61: 4551-4556
• 31 Estevez-Braun A, Estevez-Reyes R, Moujir LM, Ravelo AG, Gonzalez AG. Antibiotic activity and absolute configuration of 8S-heptadeca-2(Z), 9(Z)-diene-4,6-diyne-1,8-diol from Bupleurum salicifolium . J Nat Prod 1994; 57: 1178-1182
• 32 Blunder M, Liu X, Kunert O, Winkler NA, Schinkovitz A, Schmiderer C, Novak J, Bauer R. Polyacetylenes from Radix et Rhizoma Notopterygii incisi with an inhibitory effect on nitric oxide production in vitro . Planta Med 2014; 80: 415-418
• 33 Xie LW, Atanasov AG, Guo DA, Malainer C, Zhang JX, Zehl M, Guan SH, Heiss EH, Urban E, Dirsch VM, Kopp B. Activity-guided isolation of NF-κB inhibitors and PPARγ agonists from the root bark of Lycium chinense Miller. J Ethnopharmacol 2014; 152: 470-477
• 34 Vogl S, Picker P, Mihaly-Bison J, Fakhrudin N, Atanasov AG, Heiss EH, Wawrosch C, Reznicek G, Dirsch VM, Saukel J, Kopp B. Ethnopharmacological in vitro studies on Austriaʼs folk medicine – an unexplored lore in vitro anti-inflammatory activities of 71 Austrian traditional herbal drugs. J Ethnopharmacol 2013; 149: 750-771
• 35 Stern ST, Zolnik BS, McLeland CB, Clogston J, Zheng J, McNeil SE. Induction of autophagy in porcine kidney cells by quantum dots: A common cellular cesponse to nanomaterials?. Toxicol Sci 2008; 106: 140-152