Anticancer and anti-inflammatory effects of cysteine metabolites of the green tea polyphenol, (-)-epigallocatechin-3-gallate

J Agric Food Chem. 2010 Sep 22;58(18):10016-9. doi: 10.1021/jf102311t.


(-)-Epigallocatechin-3-gallate (EGCG) has been shown to have cancer preventive activity in vitro and in vivo. We have previously shown that EGCG can undergo conjugation to cysteine to form 2'-cysteinyl-EGCG and 2''-cysteinyl-EGCG. Studies of thiol-conjugated metabolites of methamphetamine indicate that such metabolites are not detoxified but retain biological activity. Here, we examined the growth inhibitory, pro-oxidant, and anti-inflammatory activities of the cysteine metabolites of EGCG. Both compounds dose-dependently inhibited the growth of colon cancer and intestinal cell lines. Both metabolites prevented aberrant arachidonic acid release and nitric oxide production by lipopolysaccharide-stimulated RAW264.7 cells. Under cell culture conditions, 2''-cysteinyl-EGCG produced H2O2 at a faster rate than EGCG. The results of the present study show that cysteine conjugates of EGCG retain the growth inhibitory, anti-inflammatory, and pro-oxidant activities of EGCG in vitro and may play a role in disease prevention in vivo. These results remain to be confirmed in vivo.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / chemistry
  • Anti-Inflammatory Agents, Non-Steroidal / metabolism
  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology*
  • Antineoplastic Agents, Phytogenic / chemistry
  • Antineoplastic Agents, Phytogenic / metabolism
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Catechin / analogs & derivatives*
  • Catechin / chemistry
  • Catechin / metabolism
  • Catechin / pharmacology
  • Cell Line, Transformed
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cysteine / analogs & derivatives*
  • Cysteine / metabolism*
  • Cysteine / pharmacology
  • Humans
  • Mice
  • Rats
  • Tea / chemistry*


  • 2''-cysteinyl-epigallocatechin-3-gallate
  • 2'-cysteinyl-epigallocatechin-3-gallate
  • Anti-Inflammatory Agents, Non-Steroidal
  • Antineoplastic Agents, Phytogenic
  • Tea
  • Catechin
  • epigallocatechin gallate
  • Cysteine