UVB-induced DNA damage, generation of reactive oxygen species, and inflammation are effectively attenuated by the flavonoid luteolin in vitro and in vivo

作者：Woelfle Ute; Esser Philipp R; Simon Haarhaus Birgit; Martin Stefan F; Lademann Juergen; Schempp Christoph M

来源：Free Radical Biology and Medicine, 2011, 50(9): 1081-1093.

DOI：10.1016/j.freeradbiomed.2011.01.027

• UVB
• DNA damage
• Luteolin
• Prostaglandins
• Reactive oxygen species
• Free radicals

Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human keratinocytes resulting in skin inflammation, photoaging, and photocarcinogenesis. The flavonoid luteolin is one of the most potent antioxidative plant polyphenols. We investigated the UV protective and antioxidant properties of luteolin in human keratinocytes in vitro, ex vivo, and in vivo. Spectrophotometric measurements revealed extinction maxima of luteolin in the UVB and UVA range. UV transmission below 370 nm was < 10%. In human skin, luteolin effectively reduced the formation of UVB-induced cyclobutane pyrimidine dimers. The free radical scavenging activity of luteolin was assessed in various cell-free and cell-based assays. In the cell-free DPPH assay the half-maximal effective concentration (EC(50)) of luteolin (12 mu g/ml) was comparable to those of Trolox (25 mu g/ml) and N-acetylcysteine (32 mu g/ml). In contrast, in the H(2)DCFDA assay performed with UVB-irradiated keratinocytes, luteolin (EC(50) 3 mu g/ml) was much more effective compared to Trolox (EC(50) 12 mu g/ml) and N-acetylcysteine (EC(50) 847 mu g/ml). Luteolin also inhibited both UVB-induced skin erythema and the upregulation of cyclooxygenase-2 and prostaglandin E(2) production in human skin via interference with the MAPK pathway. These data suggest that luteolin may protect human skin from UVB-induced damage by a combination of UV-absorbing, DNA-protective, antioxidant, and anti-inflammatory properties.

• 出版日期2011-5-1