Comparison of Inhibitory Potency of Various Antioxidants on the Activation of BV2 Microglial Cell Lines Induced by LPS

  • Kong, Pil-Jae (Departments of Pharmacology, College of Medicine, Kangwon National University) ;
  • Park, Jong-Ik (Departments of Pharmacology, College of Medicine, Kangwon National University) ;
  • Kwon, Oh-Yoon (Departments of Pharmacology, College of Medicine, Kangwon National University) ;
  • Han, Yoon-Hee (Departments of Pharmacology, College of Medicine, Kangwon National University) ;
  • Kim, Soo-Young (Departments of Pharmacology, College of Medicine, Kangwon National University) ;
  • Lee, Su-Nam (Departments of Anesthesiology, College of Medicine, Kangwon National University) ;
  • Son, Hee-Jeong (Departments of Anesthesiology, College of Medicine, Kangwon National University) ;
  • Kim, Sung-Soo (Departments of Pharmacology, College of Medicine, Kangwon National University)
  • Published : 2007.02.28

Abstract

Antioxidant properties have been proposed as a mechanism for the putative anti-inflammatory effects of phenolic compounds. To reveal the relationship between antioxidant activity and anti-inflammatory effects of various antioxidants, we measured 1, 1-diphenyl-2-picryhydrazyl(DPPH)-reducing activity and examined the inhibitory effects on LPS-induced inflammation-related gene expression in the BV2 microglial cell line. Lipopolysaccharide(LPS)(0.2 ${\mu}g/ml$) was used with or without antioxidants to treat cells, and the regulation of iNOS and cytokine gene expression was monitored using an RNase protection assay(RPA). Although, all tested antioxidants had similar DPPH-reducing activity and inhibited nitrite production, but the curcuminoid antioxidants(ferulic acid, caffeic acid, and curcumin) inhibited LPS-induced gene expression(iNOS, $TNF-\alpha,\;IL-1{\beta}$, IL-6, and IL-1 Ra) in a concentration-dependent manner. Other tested antioxidants did not exhibit the same effects; N-acetylcysteine(NAC) only began to suppress $IL-1{\beta}$ gene expression just below the concentration at which cytotoxicity occurred. Moreover, the antioxidant potency of curcuminoids appeared to have no correlation with anti-inflammatory potency. Only curcumin could inhibit LPS-induced microglial activation at a micromolar level. These data suggest that curcumin may be a safe antioxidant possessing anti-inflammatory activity.

Keywords

References

  1. Araki E, Forster C, Dubinsky JM, Ross ME, Iadecola C. Cyclooxygenase- 2 inhibitor ns-398 protects neuronal cultures from lipopolysaccharide-induced neurotoxicity. Stroke 32: 2370- 2375, 2001 https://doi.org/10.1161/hs1001.096057
  2. Blasi E, Barluzzi R, Bocchini V, Mazzolla R, Bistoni F. Immortalization of murine microglial cells by a v-raf/v-myc carrying retrovirus. J Neuroimmunol 27: 229-237, 1990 https://doi.org/10.1016/0165-5728(90)90073-V
  3. Bocchini V, Mazzolla R, Barluzzi R, Blasi E, Sick P, Kettenmann H. An immortalized cell line expresses properties of activated microglial cells. J Neurosci Res 31: 616-621, 1992 https://doi.org/10.1002/jnr.490310405
  4. Boje KM, Arora PK. Microglial-produced nitric oxide and reactive nitrogen oxides mediate neuronal cell death. Brain Res 587: 250 -256, 1992 https://doi.org/10.1016/0006-8993(92)91004-X
  5. Bronstein DM, Perez-Otano I, Sun V, Mullis Sawin SB, Chan J, Wu GC, Hudson PM, Kong LY, Hong JS, McMillian MK. Glia-dependent neurotoxicity and neuroprotection in mesencephalic cultures. Brain Res 704: 112-116, 1995 https://doi.org/10.1016/0006-8993(95)01189-7
  6. Chao CC, Hu S, Molitor TW, Shaskan EG, Peterson PK. Activated microglia mediate neuronal cell injury via a nitric oxide mechanism. J Immunol 149: 2736-2741, 1992
  7. Chomczynski P, Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem 162: 156-159, 1987
  8. Frautschy SA, Hu W, Kim P, Miller SA, Chu T, Harris-White ME, Cole GM. Phenolic anti-inflammatory antioxidant reversal of Abeta-induced cognitive deficits and neuropathology. Neurobiol Aging 22: 993-1005, 2001 https://doi.org/10.1016/S0197-4580(01)00300-1
  9. Gonzalez-Scarano F, Baltuch G. Microglia as mediators of inflammatory and degenerative diseases. Annu Rev Neurosci 22: 219- 240, 1999 https://doi.org/10.1146/annurev.neuro.22.1.219
  10. Green LC, Wagner DA, Glogowski J, Skipper PL, Wishnok JS, Tannenbaum SR. Analysis of nitrate, nitrite, and [15N]nitrate in biological fluids. Anal Biochem 126: 131-138, 1982 https://doi.org/10.1016/0003-2697(82)90118-X
  11. Griffin WS. Inflammation and neurodegenerative diseases. Am J Clin Nutr 83: 470S-474S, 2006
  12. Haddad JJ. Antioxidant and prooxidant mechanisms in the regulation of redox(y)-sensitive transcription factors. Cell Signal 14: 879-897, 2002 https://doi.org/10.1016/S0898-6568(02)00053-0
  13. Huang MT, Lysz T, Ferraro T, Abidi TF, Laskin JD, Conney AH. Inhibitory effects of curcumin on in vitro lipoxygenase and cyclooxygenase activities in mouse epidermis. Cancer Res 51: 813 -819, 1991
  14. Hwang BY, Kim HS, Lee JH, Hong YS, Ro JS, Lee KS, Lee JJ. Antioxidant benzoylated flavan-3-ol glycoside from Celastrus orbiculatus. J Nat Prod 64: 82-84, 2001 https://doi.org/10.1021/np000251l
  15. Kim YS, Joh TH. Microglia, major player in the brain inflammation: their roles in the pathogenesis of Parkinson's disease. Exp Mol Med 38: 333-347, 2006 https://doi.org/10.1038/emm.2006.40
  16. Lim GP, Chu T, Yang F, Beech W, Frautschy SA, Cole GM. The curry spice curcumin reduces oxidative damage and amyloid pathology in an Alzheimer transgenic mouse. J Neurosci 21: 8370-8377, 2001 https://doi.org/10.1523/JNEUROSCI.21-21-08370.2001
  17. Liu B, Gao HM, Wang JY, Jeohn GH, Cooper CL, Hong JS. Role of nitric oxide in inflammation-mediated neurodegeneration. Ann N Y Acad Sci 962: 318-331, 2002 https://doi.org/10.1111/j.1749-6632.2002.tb04077.x
  18. McCarty MF. Down-regulation of microglial activation may represent a practical strategy for combating neurodegenerative disorders. Med Hypotheses 67: 251-269, 2006 https://doi.org/10.1016/j.mehy.2006.01.013
  19. McGuire SO, Ling ZD, Lipton JW, Sortwell CE, Collier TJ, Carvey PM. Tumor necrosis factor alpha is toxic to embryonic mesencephalic dopamine neurons. Exp Neurol 169: 219-230, 2001 https://doi.org/10.1006/exnr.2001.7688
  20. Ono K, Hasegawa K, Naiki H, Yamada M. Curcumin has potent anti-amyloidogenic effects for Alzheimer's beta-amyloid fibrils in vitro. J Neurosci Res 75: 742-750, 2004 https://doi.org/10.1002/jnr.20025
  21. Rahman I, Marwick J, Kirkham P. Redox modulation of chromatin remodeling: impact on histone acetylation and deacetylation, NF-kappaB and pro-inflammatory gene expression. Biochem Pharmacol 68: 1255-1267, 2004 https://doi.org/10.1016/j.bcp.2004.05.042
  22. Sawada M, Imamura K, Nagatsu T. Role of cytokines in inflammatory process in Parkinson's disease. J Neural Transm Suppl: 373-381, 2006