Biomedical Science Letters (대한의생명과학회지)

The Korean Society for Biomedical Laboratory Sciences (대한의생명과학회)
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Inhibitory Effects of EGCG on the Dopaminergic Neurons

  • Heo, Tag (Departments of Emergency Medicine, Chonnam National University Medical School) ;
  • Jang, Su-Jeong (Departments of Physiology, Chonnam National University Medical School) ;
  • Kim, Song-Hee (Departments of Physiology, Chonnam National University Medical School) ;
  • Jeong, Han-Seong (Departments of Physiology, Chonnam National University Medical School) ;
  • Park, Jong-Seong (Departments of Physiology, Chonnam National University Medical School)
  • ;
  • ;
  • ;
  • ;
  • 박종성 (전남대학교 의과대학 생리학교실)
  • Published : 2009.06.30
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Abstract

This study was designed to investigate the effects of high concentration of (-)-epigallocatechin-3-gallate(EGCG) on the neuronal activity of rat substantia nigra dopaminergic neurons. Sprague-Dawley rats aged 14 to 16 days were decapitated under ether anesthesia. After treatment with pronase and thermolysin, the dissociated dopaminergic neurons were transferred into a chamber on an inverted microscope. Spontaneous action potentials and potassium currents were recorded by standard patch-clamp techniques under current and voltage-clamp modes respectively. 18 dopaminergic neurons(80%) revealed inhibitory responses to 40 and 100 ${\mu}M$ of EGCG and 4 neurons(20%) did not respond to EGCG. The spike frequency and resting membrane potential of these cells were decreased by EGCG. The amplitude of afterhyperpolarization was increased by EGCG. Whole potassium currents of dopaminergic neurons were increased by EGCG(n=10). These experimental results suggest that high concentration EGCG decreases the neuronal activity of the dopaminergic neurons by altering the resting membrane potential and afterhyperpolarization.

Keywords

References

  1. Bae JH, Mun KC, Park WK, Lee SR, Suh SI, Baek WK, Yim MB, Kwon TK, Song DK. EGCG attenuates AMPA-induced intracellular calcium increase in hippocampal neurons. Biochem Biophys Res Commun. 2002. 290: 1506-1512. https://doi.org/10.1006/bbrc.2002.6372
  2. Blum D, Torch S, Lambeng N, Nissou M, Benabid AL, Sadoul R, Verna JM. Molecular pathways involved in the neurotoxicity of 6-OHDA, dopamine and MPTP: contribution to the apoptotic theory in Parkinson's disease. Prog Neurobiol. 2001. 65: 135-172. https://doi.org/10.1016/S0301-0082(01)00003-X
  3. Campos-Toimil M, Orallo F. Effects of (-)-epigallocatechin-3- gallate in $Ca^{2+}$-permeable non-selective cation channels and voltage-operated $Ca^{2+}$ channels in vascular smooth muscle cells Life Sci. 2007. 80: 2147-2153. https://doi.org/10.1016/j.lfs.2007.04.005
  4. Cordey M, Gundimeda U, Gopalakrishna R, Pike CJ. Estrogen activates protein kinase C in neurons: role in neuroprotection. J Neurochem. 2003. 84: 1340-1348. https://doi.org/10.1046/j.1471-4159.2003.01631.x
  5. Deng HM, Yin ST, Yan D, Tang ML, Li CC, Chen JT, Wang M, Ruan DY. Effects of EGCG on voltage-gated sodium channels in primary cultures of rat hippocampal CA1 neurons. Toxicology 2008. 252: 1-8. https://doi.org/10.1016/j.tox.2008.07.053
  6. Graham HN. Green tea composition, consumption, and polyphenol chemistry. Prev Med. 1992. 21: 334-350. https://doi.org/10.1016/0091-7435(92)90041-F
  7. Gu X, Blatz AL, German DC. Subtypes of substantia nigra dopaminergic neurons revealed by apamin: autoradiographic and electrophysiological studies. Brain Res Bull. 1992. 28: 435-440. https://doi.org/10.1016/0361-9230(92)90044-X
  8. Homma T, Hirai K, Hara Y, Katayama Y. Tea catechin, (-)- epigallocatechin gallate, causes membrane depolarizations of myenteric neurons in the guinea-pig small intestine. Neurosci Lett. 2001. 309: 93-96. https://doi.org/10.1016/S0304-3940(01)02035-3
  9. Jeong HS, Jang S, Jang MJ, Lee SG, Kim TS, Heo T, Lee JH, Jun JY, Park JS. Effects of (-)-epigallocatechin-3-gallate on the activity of substantia nigra dopmainergic neurons. Brain Res. 2007. 1130: 114-118. https://doi.org/10.1016/j.brainres.2006.10.078
  10. Jeong HS, Kim YS, Park JS. Modulation of neuronal activity by EGCG. Brain Res. 2005. 1047: 267-270. https://doi.org/10.1016/j.brainres.2005.04.033
  11. Johnson SW, Seutin V. Bicuculline methiodide potentiates NMDAdependent burst firing in rat dopamine neurons by blocking apamin-sensitive $Ca^{2+}$-activated $K^+$currents. Neurosci Lett. 1997. 231: 13-16. https://doi.org/10.1016/S0304-3940(97)00508-9
  12. Johnston AR, MacLeod NK, Dutia MS. Ion conductances contributing to spike repolarization and afterpotential in ratmedial vestibular nucleus neurons. J Physiol. 1994. 481: 61-77.
  13. Kaplan DR, Miller FD. Neurotrophin signal transduction in the nervous system. Curr Opin Neurobiol. 2000. 10: 381-391. https://doi.org/10.1016/S0959-4388(00)00092-1
  14. Katayama Y, Homma T, Hara Y, Hirai K. Tea catechin, (-)- epigallocatechin gallate, facilitates cholinergic ganglion transmission in the myenteric plexus of the guinea-pig small intestine. Neurosci Lett. 2002. 319: 63-66. https://doi.org/10.1016/S0304-3940(01)02545-9
  15. Kay AR, Wong RK. Isolation of neurons suitable for patchclamping from adult mammalian central nervous systems. J Neurosci Methods 1986, 16: 227-238. https://doi.org/10.1016/0165-0270(86)90040-3
  16. Kim TH, Lim JM, Kim SS, Kim J, Park M, Song JH. Effects of (-) epigallocatechin-3-gallate on $Na^+$ currents in rat dorsal root ganglion neurons. Eur J Pharmacol. 2009. 604: 20-26 https://doi.org/10.1016/j.ejphar.2008.12.015
  17. Lee JH, Song DK, Jung CH, Shin DH, Park JW, Kwon TK, Jang BC, Mun KC, Kim SP, Suh SI, Bae JH. (-)-Epigallocatechin gallate attenuates glutamate-induced cytotoxicity via intracellular $Ca^{2+}$ modulation in PC12 cells. Clin Exp Pharmacol Physiol. 2004. 31: 530-536. https://doi.org/10.1111/j.1440-1681.2004.04044.x
  18. Levites Y, Weinreb O, Maor G, Youdim MB, Mandel S. Green tea polyphenol (-)-epigallocatechin-3-gallate prevents N-methyl- 4-phenyl-1,2,3,6-tetrahydropyridine-induced dopaminergic neurodegeneration. J Neurochem. 2001. 78: 1073-1082. https://doi.org/10.1046/j.1471-4159.2001.00490.x
  19. Maher P. How protein kinase C activation protects nerve cells from oxidative stress-induced cell death. J Neurosci. 2001. 21: 2929-2938.
  20. Mandel S, Weinreb O, Amit T, Youdim, MB. Cell signaling pathways in the neuroprotective actions of the green tea polyphenol (-)-epigallocatechin-3-gallate: implications for neurodegenerative diseases. J Neurochem. 2004. 88: 1555 -1569. https://doi.org/10.1046/j.1471-4159.2003.02291.x
  21. Nakagawa K, Miyazawa T. Absorption and distribution of tea catechin, (-)-epigallocatechin-3-gallate, in the rat. J Nutr Sci Vitaminol. (Tokyo) 1997, 43: 679-684. https://doi.org/10.3177/jnsv.43.679
  22. Overton PG, Clark D. Burst firing in midbrain dopaminergic neurons. Brain Res Brain Res Rev. 1997. 25: 312-334. https://doi.org/10.1016/S0165-0173(97)00039-8
  23. Pan MH, Lin-Shiau SY, Ho CT, Lin JH, Lin JK. Suppression of lipopolysaccharide-induced nuclear factor-kappaB activity by theaflavin-3,3'-digallate from black tea and other polyphenols through down-regulation of IkappaB kinase activity in macrophages. Biochem Pharmacol. 2000. 15: 357-367.
  24. Prisco S, Natoli S, Bernardi G, Mercuri NB. Group I metabotropic glutamate receptors activate burst firing in rat midbrain dopaminergic neurons. Neuropharmacology 2002. 42: 289 -296. https://doi.org/10.1016/S0028-3908(01)00192-7
  25. Sah P. $Ca(^{2+})$-activated $K^+$ currents in neurones: types, physiological roles and modulation. Trends Neurosci. 1996. 19:150-154. https://doi.org/10.1016/S0166-2236(96)80026-9
  26. Sah P, Faber ES. Channels underlying neuronal calcium-activated potassium currents. Prog Neurobiol. 2002. 66: 345-353. https://doi.org/10.1016/S0301-0082(02)00004-7
  27. Shepard PD, Bunney BS. Repetitive firing properties of putative dopamine-containing neurons in vitro: regulation by an apamin-sensitive $Ca(^{2+})$-activated $K^+$ conductance. Exp Brain Res. 1991. 86:141-150.
  28. Singer CA, Figueroa-Masot XA, Batchelor RH, Dorsa DM. The mitogen-activated protein kinase pathway mediates estrogen neuroprotection after glutamate toxicity in primary cortical neurons. J Neurosci. 1999. 19: 2455-2463.
  29. Suganuma M, Okabe S, Oniyama M, Tada Y, Ito H, Fujiki H. Wide distribution of $[^3H$](-)-epigallocatechin gallate, a cancer preventive tea polyphenol, in mouse tissue. Carcinogenesis 1998. 19: 1771-1776. https://doi.org/10.1093/carcin/19.10.1771
  30. Zaveri NT. Green tea and its polyphenolic catechins: medicinal uses in cancer and noncancer applications. Life Sci. 2006. 78: 2073-2080. https://doi.org/10.1016/j.lfs.2005.12.006