Pal Harish Chandra, Athar Mohammad, Elmets Craig A, Afaq Farrukh
Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL.
Photochem Photobiol. 2015 Jan-Feb;91(1):225-34. doi: 10.1111/php.12337. Epub 2014 Oct 7.
Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations and alterations in signaling pathways eventually leading to skin cancer. In this study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB-exposed SKH-1 hairless mouse skin. Mice were exposed to 180 mJ cm(-2) of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB-exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX-2, PGE2 as well as its receptors (EP1-EP4) and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL-1β and IL-6 in UVB-exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB-induced expression of PI3K, phosphorylation of AKT and activation of the NFκB signaling pathway in mouse skin. Overall, these data suggest that fisetin may be useful against UVB-induced cutaneous inflammation and DNA damage.
太阳紫外线B(UVB)辐射已被证明可诱发炎症、DNA损伤、p53突变以及信号通路改变,最终导致皮肤癌。在本研究中,我们调查了非瑟酮是否能减轻UVB照射的SKH-1无毛小鼠皮肤中的炎症反应,并调节PI3K/AKT/NFκB细胞存活信号通路。小鼠每隔一天接受180 mJ/cm²的UVB辐射,共照射七次,每次UVB照射15分钟后局部应用非瑟酮(250和500 nmol)。对UVB照射的小鼠进行非瑟酮治疗可减少增生并减少炎症细胞浸润。非瑟酮治疗还降低了炎症介质如COX-2、PGE2及其受体(EP1-EP4)以及MPO活性。此外,非瑟酮降低了UVB照射皮肤中炎症细胞因子TNFα、IL-1β和IL-6的水平。非瑟酮治疗还减少了细胞增殖标志物以及DNA损伤,p53和p21蛋白表达增加证明了这一点。进一步研究表明,非瑟酮抑制了UVB诱导的小鼠皮肤中PI3K的表达、AKT的磷酸化和NFκB信号通路的激活。总体而言,这些数据表明非瑟酮可能对UVB诱导的皮肤炎症和DNA损伤有效。