The green tea polyphenol (-)-epigallocatechin-3-gallate inhibits leukocyte activation by bacterial formylpeptide through the receptor FPR.
Although green tea polyphenol catechin is considered as a potential anti-inflammatory agent, its effect on bacterial component-induced inflammation has been poorly investigated. We examined the capacity of epigallocatechin gallate (EGCG) to regulate leukocyte responses to bacterial chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (fMLF), which is recognized by a human G protein-coupled receptor FPR on phagocytic leukocytes. Pretreatment of human monocytic cells or FPR-transfected rat basophilic leukemia cells (ETFR cells) with EGCG significantly inhibited fMLF-induced chemotaxis. Intraperitoneal administration of EGCG in mice suppressed fMLF-induced leukocyte infiltration into the air pouch created in the skin. Mechanistic studies revealed that EGCG dose-dependently suppressed fMLF-induced calcium flux in monocytic cells and ETFR cells. fMLF-induced ETFR cell migration was significantly inhibited by a specific MEK1/2 inhibitor, PD98059, which was associated with reduction in fMLF-induced ERK1/2 phosphorylation. These results suggest that EGCG inhibits FPR-mediated leukocyte activation thus is a promising anti-inflammatory compound.
Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, China.
Jingjing
J
Zhu
Oumei
O
Wang
Lingfei
L
Ruan
Xinwei
X
Hou
Youhong
Y
Cui
Ji Ming
JM
Wang
Yingying
Y
Le
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D028241:Camellia sinensis / Q000276:immunology; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000276:immunology; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007249:Inflammation; D007274:Injections, Intraperitoneal; D015471:Leukemia, Basophilic, Acute / Q000097:blood / Q000188:drug therapy / Q000276:immunology; D051379:Mice; D009000:Monocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000276:immunology / Q000378:metabolism*; D051381:Rats; D044042:Receptors, Formyl Peptide / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D014162:Transfection; D019076:Transgenes
D000975:Antioxidants; D005419:Flavonoids; D044042:Receptors, Formyl Peptide; D009240:N-Formylmethionine Leucyl-Phenylalanine; D002392:Catechin; C045651:epigallocatechin gallate; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one