基于JAK/STAT信号通路探究黄连素对溃疡性结肠炎小鼠结肠皮细胞凋亡作用

Effects of berberine on colon dermal cell apoptosis in micewith ulcerative colitis based on JAK/STAT signaling pathway

目的探讨黄连素调控JAK/STAT信号通路对溃疡性结肠炎(ulcerative colitis,UC)小鼠结肠上皮细胞和外周血中性粒细胞(peripheral blood neutrophils,PMN)凋亡的影响。方法葡聚糖硫酸钠(dextran sulfact sodium,DSS)法构建UC小鼠模型,随机分为对照组、UC组、黄连素低、中、高剂量组和阳性药物组(美沙拉嗪肠溶片组),另将小鼠随机分为UC组、黄连素高剂量组、AG490组、黄连素高剂量+AG490组。比较各组血清肿瘤坏死因子α(TNF-α)、白介素6(IL-6)水平和结肠上皮细胞凋亡、PMN凋亡情况,Western blot检测结肠组织凋亡相关、JAK/STAT信号通路相关蛋白表达情况。结果黄连素各剂量组以及阳性药物组血清TNF-α、IL-6水平、结肠上皮细胞凋亡率、Fas、FasL、Bax、caspase-3、p-JAK2/JAK2、p-STAT3/STAT3蛋白表达明显低于UC组(P<0.05),且随黄连素剂量增加逐渐降低(P<0.05);黄连素各剂量组以及阳性药物组PMN凋亡率、Bcl-2蛋白表达明显高于UC组(P<0.05),且随黄连素剂量增加逐渐升高(P<0.05);AG490能逆转黄连素上述作用(P<0.05)。结论黄连素可通过调控JAK/STAT信号通路抑制UC小鼠结肠上皮细胞凋亡,促进PMN凋亡,进而发挥治疗UC的作用。

Aim To analyze the effects of berberine on the apoptosis of colon epithelial cells and polymorphonuclear neutrophils(PMNs)in mice with ulcerative colitis(UC)by regulating JAK/STAT signaling pathway.Methods The UC mouse models were established by dextran sulfate sodium(DSS)method and were randomly divided into control group,UC group,low-dose,middle-dose and high-dose berberine groups and positive drug group(mesalazine enteric-coated tablet group).In addition,the mice were randomly divided into UC group,high-dose berberine group,AG490 group,and high-dose berberine+AG490 group.Levels of serum tumor necrosis factorα(TNF-α)and interleukin 6(IL-6)and colon epithelial cell apoptosis and PMN apoptosis were compared among the groups.Western blot was used to detect the expressions of colon tissue apoptosis-related and JAK/STAT signaling pathway-related proteins.Results The levels of serum TNF-αand IL-6,apoptosis rate of colon epithelial cell and protein expressions of Fas,FasL,Bax,caspase-3,p-JAK2/JAK2 and p-STAT3/STAT3 in each dose berberine group and positive drug group were significantly lower than those in UC group(P<0.05),and the above indicators in berberine groups were reduced gradually(P<0.05).The PMN apoptosis rate and Bcl-2 protein expression were significantly higher in each dose berberine group and positive drug group than those in UC group(P<0.05),and the two indicators increased gradually in berberine groups(P<0.05).AG490 could reverse the above effects of berberine(P<0.05).Conclusions Berberine can inhibit the apoptosis of colon epithelial cell and promote the apoptosis of PMN in UC mice by regulating the JAK/STAT signaling pathway,and then play a role in the treatment of UC.