A metabolomics approach shows that catechin-enriched green tea attenuates ultraviolet B-induced skin metabolite alterations in mice

In this study, catechin-enriched green tea (CGT) administration significantly attenuated ultraviolet (UV) B-induced mouse skin alterations, i.e., increases in wrinkle formation, thickness, erythema, and transepidermal water loss, and decreases in hydration, elasticity, and collagen fiber content. The metabolites in the mouse skin after UVB irradiation and CGT administration were profiled using comprehensive MS-based metabolomics techniques such as ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (TOF-MS), gas chromatography-TOF-MS, and NanoMate tandem-MS. From these analysis, we revel that Normal, UVB-irradiated, and UVB-irradiated with CGT administrated groups clearly discriminated from each other in partial least squares-discriminant analysis models, and CGT administration attenuated UVB-induced alteration of skin metabolites such as lysophospholipids, fatty acids, ceramides, amino acids, organic compounds, lipids, and nucleobases. Among them, purine nucleobases (inosine and hypoxanthine), ascorbic acid, and lactose were remarkably influenced by CGT administration, which indicated that these metabolites could be biomarkers to explain CGT effects on UVB-irradiated skin. Our results suggested that CGT administration was effective in reducing the levels of UVB-induced alterations of numerous mouse skin metabolites, and these metabolites were might highly relevant to observed changes in skin conditions.