British Journal of Nutrition

Full Papers

Human and Clinical Nutrition

Oral green tea catechin metabolites are incorporated into human skin and protect against UV radiation-induced cutaneous inflammation in association with reduced production of pro-inflammatory eicosanoid 12-hydroxyeicosatetraenoic acid

Lesley E. Rhodesa1 c1, Gemma Darbya1, Karen A. Masseya2, Kayleigh A. Clarkea3, Tristan P. Dewa3, Mark D. Farrara1, Susan Bennetta1, Rachel E. B. Watsona1, Gary Williamsona3 and Anna Nicolaoua2

a1 Photobiology Unit, Dermatology Centre, Institute of Inflammation and Repair, University of Manchester, Manchester Academic Health Science Centre, Salford Royal NHS Foundation Hospital, Manchester M6 8HD, UK

a2 School of Pharmacy and Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, UK

a3 School of Food Science and Nutrition, University of Leeds, Leeds, UK

Abstract

Green tea catechins (GTC) reduce UV radiation (UVR)-induced inflammation in experimental models, but human studies are scarce and their cutaneous bioavailability and mechanism of photoprotection are unknown. We aimed to examine oral GTC cutaneous uptake, ability to protect human skin against erythema induced by a UVR dose range and impact on potent cyclo-oxygenase- and lipoxygenase-produced mediators of UVR inflammation, PGE2 and 12-hydroxyeicosatetraenoic acid (12-HETE), respectively. In an open oral intervention study, sixteen healthy human subjects (phototype I/II) were given low-dose GTC (540 mg) with vitamin C (50 mg) daily for 12 weeks. Pre- and post-supplementation, the buttock skin was exposed to UVR and the resultant erythema quantified. Skin blister fluid and biopsies were taken from the unexposed and the UVR-exposed skin 24 h after a pro-inflammatory UVR challenge (three minimal erythema doses). Urine, skin tissue and fluid were analysed for catechin content and skin fluid for PGE2 and 12-HETE by liquid chromatography coupled to tandem MS. A total of fourteen completing subjects were supplement compliant (twelve female, median 42·5 years, range 29–59 years). Benzoic acid levels were increased in skin fluid post-supplementation (P= 0·03), and methylated gallic acid and several intact catechins and hydroxyphenyl-valerolactones were detected in the skin tissue and fluid. AUC analysis for UVR erythema revealed reduced response post-GTC (P= 0·037). Pre-supplementation, PGE2 and 12-HETE were UVR induced (P= 0·003, 0·0001). After GTC, UVR-induced 12-HETE reduced from mean 64 (sd 42) to 41 (sd 32) pg/μl (P= 0·01), while PGE2 was unaltered. Thus, GTC intake results in the incorporation of catechin metabolites into human skin associated with abrogated UVR-induced 12-HETE; this may contribute to protection against sunburn inflammation and potentially longer-term UVR-mediated damage.

(Received September 20 2012)

(Revised November 26 2012)

(Accepted November 26 2012)

(Online publication January 28 2013)

Key Words:

  • Green tea catechins;
  • Bioavailability;
  • Skin;
  • 12-Hydroxyeicosatetraenoic acid

Correspondence

c1 Corresponding author: Professor L. E. Rhodes, fax +44 161 2061156, email lesley.e.rhodes@manchester.ac.uk

Footnotes

  Abbreviations: 12-HETE, 12-hydroxyeicosatetraenoic acid; COX, cyclo-oxygenase; EC, ( − )-epicatechin; ECG, ( − )-EC-3-O-gallate; EGC, ( − )-epigallocatechin; EGCG, ( − )-EGC-3-O-gallate; GTC, green tea catechins; LOX, lipoxygenase; M4, 5-(3′,4′,5′-trihydroxyphenyl)-γ-valerolactone; M6, 5-(3′,4′-dihydroxyphenyl)-valerolactone; M6′, 5-(3′,5′-dihydroxyphenyl)-valerolactone; MED, minimal erythema dose; UVR, UV radiation