雷帕霉素软膏对银屑病小鼠模型的治疗作用及相关机制研究

Effect of rapamycin ointment on psoriasis in mice and its possible mechanisms

目的探讨雷帕霉素(RAP)软膏对寻常型银屑病(PSO)小鼠皮肤的影响及相关机制。方法45只BALB/c小鼠分为3组:空白对照组、模型组和实验组,每组15只。模型组和实验组利用5%咪喹莫特乳膏建立银屑病小鼠动物模型,空白对照组不建模。实验组建模后连续给药0.1%雷帕霉素软膏涂抹14 d,其余两组给予生理盐水湿润皮肤,每日3次/d,连续涂抹14 d。三组小鼠于15 d检测血清细胞因子干扰素γ(IFN-γ),白介素4(IL-4)的表达;实时荧光定量PCR(q-PCR)检测酪氨酸蛋白激酶2(JAK2)、信号转导与转录因子1(STAT1)和信号转导与转录因子3(STAT3)mRNA表达;Western blotting检测磷酸化p-JAK2、p-STAT1和p-STAT3蛋白表达。结果与空白对照组比较,模型组血清细胞因子IFN-γ含量上调(P<0.05),用药后实验组血清中细胞因子IFN-γ水平明显低于模型组(P<0.05),IL-4水平三组比较差异无统计学意义(P>0.05);q-PCR显示,与空白对照组比较,模型组皮损区JAK2、STAT1和STAT3 mRNA表达显著升高(P<0.05),用药后实验组JAK2、STAT1和STAT3 mRNA表达显著低于模型组(P<0.05);Western blotting显示,与空白对照组比较,模型组皮损区皮损区p-JAK2、p-STAT1和p-STAT3表达显著升高(P<0.05),实验组p-JAK2、p-STAT1和p-STAT3表达显著低于模型组(P<0.05)。结论雷帕霉素可通过抑制JAK/STAT信号通路降低银屑病小鼠炎性因子表达,从而对银屑病小鼠起保护作用。

Objective To investigate the effect of rapamycin ointment( RAP) on psoriasis in mice and its possible mechanisms. Methods45 BALB/c mice were divided into 3 groups,the control group,model group and the test group. The model group and the test group mice were made by 5% propranolol emulsion. 0. 1% rapamycin ointment was used to treat psoriasis mice in the test group. The other two groups were given saline to moisturize the skin 3 times a day for 14 days. Then,the levels of several cytokines,including interleukin( IL)-5 and interferon( IFN)-γ from the serum samples were detected by Elisa kit at 15 days. Meanwhile,the mRNA expression of JAK2,STAT1 and STAT3 were detected by q-PCR. The protein expression of p-JAK2,p-STAT1 and p-STAT3 were valued by western blotting. Results Compared with the blank control group,the serum cytokine IFN-γ content in the model group was up-regulated( P < 0. 05). RAP markedly decreased the level of IFN-γ from the serum samples at 15 days( P < 0. 05),meanwhile,there was no significant difference in IL-4 levels between the three groups( P> 0. 05). q-PCR showed that compared with the blank control group,the expression of JAK2,STAT1 and STAT3 mRNA in the lesion group was significantly increased( P < 0. 05). The expression of JAK2,STAT1 and STAT3 mRNA in the experimental group was significantly lower than that in the model group( P < 0. 05). Western blotting showed that compared with the blank control group,the expression of p-JAK2,p-STAT1 and p-STAT3 in the lesion area of the model group was significantly increased( P < 0. 05),experimental group p-JAK2,p-STAT1 and p-STAT3 expression were significantly lower than the model group( P < 0. 05). Conclusion RAP may protect the psoriasis mice through suppressing the inflammatory reaction via JAK/STAT signaling pathway.