柴胡皂苷A通过调节ERK/NF-κB信号通路减轻小鼠玫瑰痤疮样炎症反应

Saikosaponin A Attenuates Rosacea-like Inflammatory Response in Mice by Regulating ERK/NF-κB Signaling Pathway

目的探讨柴胡皂苷A(SSA)调节细胞外信号调节激酶(ERK)/核因子κB(NF-κB)信号通路对小鼠玫瑰痤疮样炎症反应的影响。方法按照随机数字表法将小鼠随机分为Ct组、Model组、低剂量SSA组(SSA-L组,37.5 mg/kg)、高剂量SSA组(SSA-H组,75 mg/kg)、盐酸多西环素(DH)组(30 mg/kg)、重组小鼠表皮生长因子(rmEGF)组(ERK激动剂,15μg/kg)、SSA-H+rmEGF组(75 mg/kg+15μg/kg),每组12只。除Ct组外,其他组小鼠均需构建玫瑰痤疮模型,Ct组小鼠背部注射4次等量的PBS。造模24 h后,进行给药处理,1次/d,持续8周。观察各组小鼠皮损变化,并进行红斑程度评分及红斑面积测定;HE染色检测小鼠背部注射部位皮肤病理损伤程度;甲苯胺蓝染色检测小鼠背部注射部位皮肤肥大细胞浸润情况;免疫荧光染色检测小鼠背部注射部位皮肤中血小板内皮细胞黏附分子1(CD31)的表达;ELISA实验检测小鼠背部注射部位皮肤中白细胞介素-6(IL-6)、S100钙结合蛋白A9(S100A9)、肿瘤坏死因子-α(TNF-α)表达;Western blot检测小鼠背部注射部位皮肤中p-ERK1/2、p-NF-κB p65蛋白表达。结果与Ct组比较,Model组红斑面积及红斑程度评分、IL-6、S100A9、TNF-α表达、p-ERK1/2、p-NF-κB p65蛋白表达升高,有大量炎性细胞浸润,肥大细胞数、CD31阳性毛细血管数增多(P<0.05);与Model组比较,SSA-L组、SSA-H组、DH组红斑面积及红斑程度评分、IL-6、S100A9、TNF-α表达、p-ERK1/2、p-NF-κB p65蛋白表达降低,病理损伤减轻,肥大细胞数、CD31阳性毛细血管数减少(P<0.05);rmEGF减弱了高剂量SSA对玫瑰痤疮小鼠炎症反应的抑制作用。结论SSA可能通过抑制ERK/NF-κB通路减轻玫瑰痤疮小鼠炎症反应。

Objective To investigate the impact of saikosaponin A(SSA)regulating extracellular signal-regulated kinase(ERK)/nuclear factorκB(NF-κB)signaling pathway on rosacea-like inflammatory response in mice.Methods Mice were randomly divided into Ct group,Model group,low-dose SSA group(SSA-L group,37.5 mg/kg),high-dose SSA group(SSA-H group,75 mg/kg),doxycycline hydrochloride(DH)group(30 mg/kg),recombinant mouse epidermal growth factor(rmEGF)group(ERK agonist,15μg/kg),and SSA-H+rmEGF group(75 mg/kg+15μg/kg)according to the random number table method,12 in each group.Except for the Ct group,mice in other groups were required to construct a rosacea model,and the mice in the Ct group were injected with the same amount of PBS on the back for 4 times.After 24 hours of modeling,drug administration was performed once a day for 8 weeks.The changes of the skin lesions of the mice in each group were observed,and the erythema degree score and the erythema area were measured;HE staining was used to detect the degree of skin pathological damage at the injection site on the back of the mice;Toluidine blue staining was used to detect the infiltration of mast cells in the skin of the mouse back injection site;immunofluorescence staining was used to detect the expression of platelet endothelial cell adhesion molecule 1(CD31)in the skin of the mouse back injection site;ELISA was used to detect the expressions of interleukin-6(IL-6),S100 calcium binding protein A9(S100A9)and tumor necrosis factor-α(TNF-α)in the skin at the back injection site of mice;Western blot was used to detect the protein expressions of p-ERK1/2 and p-NF-κB p65 in the skin of the back injection site of mice.Results Compared with the Ct group,the erythema area,erythema degree score,the expressions of IL-6,S100A9,TNF-α,and the protein expressions of p-ERK1/2 and p-NF-κB p65 in the Model group were increased,and a large number of inflammatory cells were infiltrated,the number of mast cells and the number of CD31 positive capillaries increased(P<0.05);compared with the Model group,the erythema area,erythema degree score,the expressions of IL-6,S100A9,TNF-α,and the protein expressions of p-ERK1/2 and p-NF-κB p65 in SSA-L group,SSA-H group,and DH group were decreased,the pathological damage was alleviated,and the number of mast cells and the number of CD31 positive capillaries decreased(P<0.05);rmEGF attenuated the inhibitory effect of high-dose SSA on inflammatory responses in mice with rosacea.Conclusion SSA may reduce the inflammatory response in rosacea mice by inhibiting the ERK/NF-κB pathway.