芜菁挥发油对紫外线诱导皮肤光老化大鼠的保护作用

Protective effect of Brassica rapa volatile oil on rat skin photo aging induced by UV

目的研究芜菁挥发油对紫外线(UV)诱导皮肤光老化大鼠的保护作用,并探讨氧化相关通路的作用机制。方法使用皮肤含水量测定仪测定经UV照射后大鼠皮肤的含水量,采用酶联免疫吸附(ELISA)法检测皮肤组织中透明质酸、Ⅰ型胶原蛋白、Ⅲ型胶原蛋白、弹性蛋白和脯氨酸的蛋白表达,化学法测定抗氧化指标,ELISA法和实时荧光PCR测定血清中氧化相关通路的蛋白和mRNA表达。将大鼠进行UV照射造模,波长为350~400 nm,每日照射60 min,光源与皮肤的距离为40 cm,持续造模50 d后。将大鼠分为对照组、模型组、芜菁挥发油高(40 g·kg^(-1))、低(20 g·kg^(-1))剂量组,芜菁挥发油高、低剂量组灌胃给予芜菁挥发油混悬液,对照组和模型组给予等量生理盐水,连续14 d。测定各组大鼠的皮肤含水量,观察大鼠皮肤组织中透明质酸、Ⅰ型胶原蛋白、Ⅲ型胶原蛋白、弹性蛋白、脯氨酸蛋白表达和抗氧化指标超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)的活力及丙二醛(MDA)的含量。探讨抗氧化通路中核因子-κB(NF-κB)、Toll样受体4(TLR4)、分裂原激活的蛋白激酶(P38-MAPK)、磷脂酰肌醇激酶(PI3K)蛋白和mRNA表达。结果芜菁挥发油可抑制皮肤光老化大鼠皮肤含水量的降低,升高透明质酸、Ⅰ型胶原蛋白、Ⅲ型胶原蛋白、弹性蛋白、脯氨酸的蛋白表达及抗氧化酶的活力,并可通过NF-κB、TLR4、P38-MAPK、PI3K通路降低大鼠体内的脂质过氧化。结论芜菁挥发油对皮肤光老化大鼠具有一定的保护作用,其机制可能是通过氧化应激通路清除体内自由基。

Objective To investigate the protective effect of Brassica rapa volatile oil on rat skin photo aging induced by ultraviolet light(UV),and to study the mechansim related to oxidation pathways.Methods The water content of skin was detected by skin water content tester in rats after irradiated by UV.The protein expressions of hyaluronic acid,typeⅠcollagen,typeⅢcollagen,elastin and proline in skin tissue were detected by ELISA.The antioxidant indexes were detected by chemical method.The expressions of protein and mRNA of oxidation-related pathway in serum were detected by ELISA and real-time PCR.The nude mouse models of subacute skin aging were established with 60 min UV exposure at the wavelength from 350 to 400 nm daily and 40 cm source-skin distance with continuous 50 days.The nude mice were randomly divided into the control group,model group,and Brassica rapa volatile oil high dose group(40 g·kg^(-1)),Brassica rapa volatile oil low dose group(20 g·kg^(-1)).Different doses of volatile oil suspension group were administered via gavage daily for continuous 14 days.The control group and model group were treated with saline for comparison.The water content of skin was detected in each group.The contents of hyaluronic acid,hydroxyproline,typeⅠcollagen,typeⅢcollagen and elastin in skin of each group were detected by kits.The water content in skin was also determined by drying method.The activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),catalase(CAT)and the content of malonaldehyde(MDA)were observed by chemical method.The expressions of nuclear factor kappa-B(NF-κB),Toll-like receptor 4(TLR4),P38-mitogen activated protein kinases(P38-MAPK),phosphatidylinositol 3-kinase(PI3K)proteins and mRNA in oxidation-related pathway were also investigated.Results The Brassica rapa volatile oil can inhibit the decrease of skin water content and increase the protein expression of hyaluronic acid,typeⅠcollagen,typeⅢcollagen,elastin and proline and the activity of antioxidant enzymes in photoaging rats,and may activate the NF-κB,TLR4,P38-MAPK,PI3K pathway to inhibit the lipid peroxidation.Conclusion The herbal group has certain anti-skin aging effect in vivo by the potential mechanism that scavenges free radicals through oxidative stress signaling pathway.