title: Phenolic acid concentrations in plasma and urine from men consuming green or black tea and potential chemopreventive properties for colon cancer.
abstract: METHODS
  Tea polyphenols are metabolized by the colonic microflora yielding phenolic metabolites, which may contribute to the health benefits of tea. We determined the serum and urine concentrations of phenolic acids, hippuric acid, and polyhydroxyphenyl-γ-valerolactones during green tea (GT) and black tea (BT) administration. The effects of (-)-epigallocatechin gallate (EGCG) and 3,4-dihydroxyphenylacetic acid (3,4-DHPAA) alone and in combination on bioavailability, intracellular metabolism, and antiproliferative activity were determined in HCT-116 colon cancer cells.
  
  
  RESULTS
  The concentration of phenolic metabolites was quantified by HPLC with electrochemical detection and MS. Urine concentrations of 4-hydroxyphenylacetic acid (4-HPAA), 3-hydroxyphenylacetic acid (3-HPAA), and polyhydroxy-γ-valerolactones were increased significantly in men drinking GT compared to control. Urine concentration of 3-O-methylgallic acid (3OMGA) was significantly increased in men drinking BT compared to control. Serum 3,4-DHPAA was significantly increased after consumption of GT and BT and 4-HPAA after GT consumption. In vitro treatment of HCT-116 colon cancer cells with 3,4-DHPAA and EGCG exhibited an additive antiproliferative effect, while methylation of 3,4-DHPAA was significantly decreased. 3OMGA exhibited the strongest antiproliferative activity among the phenolic acids.
  
  
  CONCLUSIONS
  The consumption of both, GT and BT, was associated with a significant increase in urinary and serum phenolic acids.
authors: Center for Human Nutrition, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. shenning@mednet.ucla.edu
authors: Susanne M
authors: SM
authors: Henning
authors: Piwen
authors: P
authors: Wang
authors: Narine
authors: N
authors: Abgaryan
authors: Roberto
authors: R
authors: Vicinanza
authors: Daniela Moura
authors: DM
authors: de Oliveira
authors: Yanjun
authors: Y
authors: Zhang
authors: Ru-Po
authors: RP
authors: Lee
authors: Catherine L
authors: CL
authors: Carpenter
authors: William J
authors: WJ
authors: Aronson
authors: David
authors: D
authors: Heber
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000493:pharmacokinetics / Q000494:pharmacology; D000368:Aged; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D028241:Camellia sinensis / Q000737:chemistry; D002392:Catechin / Q000031:analogs & derivatives / Q000493:pharmacokinetics / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D003110:Colonic Neoplasms / Q000517:prevention & control*; D005707:Gallic Acid / Q000031:analogs & derivatives / Q000097:blood / Q000652:urine; D045325:HCT116 Cells / Q000187:drug effects; D006626:Hippurates / Q000097:blood / Q000652:urine; D006801:Humans; D062385:Hydroxybenzoates / Q000097:blood / Q000652:urine; D007783:Lactones / Q000652:urine; D008297:Male; D008875:Middle Aged; D010648:Phenylacetates / Q000097:blood* / Q000652:urine*; D011471:Prostatic Neoplasms / Q000150:complications / Q000178:diet therapy; D013662:Tea / Q000737:chemistry*
chemical_list: C406787:(-)-5-(3',4',5'-dihydroxyphenyl)-valerolactone; D016588:Anticarcinogenic Agents; D006626:Hippurates; D062385:Hydroxybenzoates; D007783:Lactones; D010648:Phenylacetates; D013662:Tea; D015102:3,4-Dihydroxyphenylacetic Acid; C008070:4-hydroxyphenylacetic acid; D005707:Gallic Acid; C025525:3-O-methylgallic acid; D002392:Catechin; C045651:epigallocatechin gallate; C017616:phenolic acid; C008069:3-hydroxybenzeneacetic acid; C030514:hippuric acid