The interaction of serum albumin with ginsenoside Rh2 resulted in the downregulation of ginsenoside Rh2 cytotoxicity

  • Lin, Yingjia (Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University) ;
  • Li, Yang (Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University) ;
  • Song, Zhi-Guang (College of Chemistry, Jilin University) ;
  • Zhu, Hongyan (Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University) ;
  • Jin, Ying-Hua (Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, College of Life Science, Jilin University)
  • Received : 2016.04.05
  • Accepted : 2016.06.23
  • Published : 2017.07.15


Background: Ginsenoside Rh2 (G-Rh2) is a ginseng saponin that is widely investigated because of its remarkable antitumor activity. However, the molecular mechanism by which (20S) G-Rh2 triggers its functions and how target animals avoid its cytotoxic action remains largely unknown. Methods: Phage display was used to screen the human targets of (20S) G-Rh2. Fluorescence spectroscopy and UV-visible absorption spectroscopy were used to confirm the interaction of candidate target proteins and (20S) G-Rh2. Molecular docking was utilized to calculate the estimated free energy of binding and to structurally visualize their interactions. MTT assay and immunoblotting were used to assess whether human serum albumin (HSA), bovine serum albumin (BSA), and bovine serum can reduce the cytotoxic activity of (20S) G-Rh2 in HepG2 cells. Results: In phage display, (20S) G-Rh2-beads and (20R) G-Rh2-beads were combined with numerous kinds of phages, and a total of 111 different human complementary DNAs (cDNA) were identified, including HSA which had the highest rate. The binding constant and number of binding site in the interaction between (20S)-Rh2 and HSA were $3.5{\times}10^5M^{-1}$ and 1, and those in the interaction between (20S) G-Rh2 and BSA were $1.4{\times}10^5M^{-1}$ and 1. The quenching mechanism is static quenching. HSA, BSA and bovine serum significantly reduced the proapoptotic effect of (20S) G-Rh2. Conclusion: HSA and BSA interact with (20S) G-Rh2. Serum inhibited the activity of (20S) G-Rh2 mainly due to the interaction between (20S) G-Rh2 and serum albumin (SA). This study proposes that HSA may enhance (20S) G-Rh2 water solubility, and thus might be used as nanoparticles in the (20S) G-Rh2 delivery process.


Supported by : National Nature Science Foundation of China


  1. Lin Y, Jiang D, Li Y, Han X, Yu D, Park JH, Jin YH. Effect of sun ginseng potentiation on epirubicin and paclitaxel-induced apoptosis in human cervical cancer cells. J Ginseng Res 2015;39:22-8.
  2. Kim YJ, Zhang D, Yang DC. Biosynthesis and biotechnological production of ginsenosides. Biotechnol Adv 2015;33(6 Pt 1):717-35.
  3. Zhang JT, Qu ZW, Liu Y, Deng HL. Preliminary study on antiamnestic mechanism of ginsenoside Rg1 and Rb1. Chin Med J (Engl) 1990;103:932-8.
  4. Zhang G, Liu A, Zhou Y, San X, Jin T, Jin Y. Panax ginseng ginsenoside-Rg2 protects memory impairment via anti-apoptosis in a rat model with vascular dementia. J Ethnopharmacol 2008;115:441-8.
  5. Kennedy DO, Scholey AB. Ginseng: potential for the enhancement of cognitive performance and mood. Pharmacol Biochem Behav 2003;75:687-700.
  6. Baek KS, Hong YD, Kim Y, Sung NY, Yang S, Lee KM, Park JY, Park JS, Rho HS, Shin SS, et al. Anti-inflammatory activity of AP-SF, a ginsenoside-enriched fraction, from Korean ginseng. J Ginseng Res 2015;39:155-61.
  7. Yang Y, Lee J, Rhee MH, Yu T, Baek KS, Sung NY, Kim Y, Yoon K, Kim JH, Kwak YS, et al. Molecular mechanism of protopanaxadiol saponin fractionmediated anti-inflammatory actions. J Ginseng Res 2015;39:61-8.
  8. Kim SJ, Kim AK. Anti-breast cancer activity of Fine black ginseng (Panax ginseng Meyer) and ginsenoside Rg5. J Ginseng Res 2015;39:125-34.
  9. Nag SA, Qin JJ, Wang W, Wang MH, Wang H, Zhang RW. Ginsenosides as anticancer agents: in vitro and in vivo activities, structure-activity relationships, and molecular mechanisms of action. Front Pharmacol 2012;3.
  10. Yang Z, Gao S, Wang JR, Yin TJ, Teng Y, Wu BJ, You M, Jiang ZH, Hu M. Enhancement of oral bioavailability of 20(S)-Ginsenoside Rh2 through improved understanding of its absorption and efflux mechanisms. Drug Metab Disposition 2011;39:1866-72.
  11. Kim H, Kim JH, Lee PY, Bae KH, Cho S, Park BC, Shin H, Park SG. Ginsenoside Rb1 is transformed into Rd and Rh2 by Microbacterium trichothecenolyticum. J Microbiol Biotechnol 2013;23:1802-5.
  12. Chi H, Kim DH, Ji GE. Transformation of ginsenosides Rb2 and Rc from Panax ginseng by food microorganisms. Biol Pharm Bull 2005;28:2102-5.
  13. Yamasaki K, Chuang VT, Maruyama T, Otagiri M. Albumin-drug interaction and its clinical implication. Biochim Biophys Acta 2013;1830:5435-43.
  14. Curry S. Lessons from the crystallographic analysis of small molecule binding to human serum albumin. Drug Metab Pharmacokinet 2009;24:342-57.
  15. Ghuman J, Zunszain PA, Petitpas I, Bhattacharya AA, Otagiri M, Curry S. Structural basis of the drug-binding specificity of human serum albumin. J Mol Biol 2005;353:38-52.
  16. Wang ZM, Ho JX, Ruble JR, Rose J, Ruker F, Ellenburg M, Murphy R, Click J, Soistman E, Wilkerson L, et al. Structural studies of several clinically important oncology drugs in complex with human serum albumin. Biochim Biophys Acta 2013;1830:5356-74.
  17. Otagiri M. A molecular functional study on the interactions of drugs with plasma proteins. Drug Metab Pharmacokinet 2005;20:309-23.
  18. Xu H, Yao N, Xu H, Wang T, Li G, Li Z. Characterization of the interaction between eupatorin and bovine serum albumin by spectroscopic and molecular modeling methods. Int J Mol Sci 2013;14:14185-203.
  19. Miele E, Spinelli GP, Miele E, Tomao F, Tomao S. Albumin-bound formulation of paclitaxel (Abraxane ABI-007) in the treatment of breast cancer. Int J Nanomedicine 2009;4:99-105.
  20. Fasano M, Curry S, Terreno E, Galliano M, Fanali G, Narciso P, Notari S, Ascenzi P. The extraordinary ligand binding properties of human serum albumin. IUBMB Life 2005;57:787-96.
  21. Kratz F. Albumin as a drug carrier: design of prodrugs, drug conjugates and nanoparticles. J Control Release 2008;132:171-83.
  22. Bae S, Ma K, Kim TH, Lee ES, Oh KT, Park ES, Lee KC, Youn YS. Doxorubicinloaded human serum albumin nanoparticles surface-modified with TNFrelated apoptosis-inducing ligand and transferrin for targeting multiple tumor types. Biomaterials 2012;33:1536-46.
  23. Arango D, Morohashi K, Yilmaz A, Kuramochi K, Parihar A, Brahimaj B, Grotewold E, Doseff AI. Molecular basis for the action of a dietary flavonoid revealed by the comprehensive identification of apigenin human targets. Proc Natl Acad Sci USA 2013;110:E2153-62.
  24. Li D, Zhu M, Xu C, Chen J, Ji B. The effect of Cu2+ or Fe3+ on the noncovalent binding of rutin with bovine serum albumin by spectroscopic analysis. Spectrochim Acta A Mol Biomol Spectrosc 2011;78:74-9.
  25. Ware WR. Oxygen quenching of fluorescence in solution: an experimental study of the diffusion process. J Phys Chem 1962;66:455-8.
  26. Li D, Mei Z, Chen X, Ji B. Characterization of the baicalein-bovine serum albumin complex without or with Cu2+ or Fe3+ by spectroscopic approaches. Eur J Med Chem 2011;46:588-99.
  27. Lakowicz JR, Weber G. Quenching of fluorescence by oxygen. A probe for structural fluctuations in macromolecules. Biochemistry 1973;12:4161-70.
  28. Chen T, Zhu S, Cao H, Shang Y, Wang M, Jiang G, Shi Y, Lu T. Studies on the interaction of salvianolic acid B with human hemoglobin bymulti-spectroscopic techniques. Spectrochim Acta A Mol Biomol Spectrosc 2011;78:1295-301.
  29. Li Q, Li Y, Wang X, Fang X, He K, Guo X, Zhan Z, Sun C, Jin YH. Co-treatment with ginsenoside Rh2 and betulinic acid synergistically induces apoptosis in human cancer cells in association with enhanced capsase-8 activation, bax translocation, and cytochrome c release. Mol Carcinog 2011;50:760-9.
  30. Guo XX, Li Y, Sun C, Jiang D, Lin YJ, Jin FX, Lee SK, Jin YH. p53-dependent Fas expression is critical for Ginsenoside Rh2 triggered caspase-8 activation in HeLa cells. Protein Cell 2014;5:224-34.
  31. Li B, Zhao J, Wang CZ, Searle J, He TC, Yuan CS, Du W. Ginsenoside Rh2 induces apoptosis and paraptosis-like cell death in colorectal cancer cells through activation of p53. Cancer Lett 2011;301:185-92.
  32. Gu Y, Wang GJ, Sun JG, Jia YW, Wang W, Xu MJ, Lv T, Zheng YT, Sai Y. Pharmacokinetic characterization of ginsenoside Rh2, an anticancer nutrient from ginseng, in rats and dogs. Food Chem Toxicol 2009;47:2257-68.
  33. Rogers TL, Johnston KP, Williams 3rd RO. Solution-based particle formation of pharmaceutical powders by supercritical or compressed fluid CO2 and cryogenic spray-freezing technologies. Drug Dev Ind Pharm 2001;27:1003-15.