黄连碱通过调控IκBα/NF-κB通路防治化疗相关性腹泻的实验研究

Coptisine Regulated IκBα/NF-κB Signaling Pathway to Treat Chemotherapy-induced Diarrhea Mice

目的观察黄连碱对化疗相关性腹泻(CID)裸鼠的保护作用,并探讨其作用机制。方法 32只裸鼠随机分为正常组、模型组、洛哌丁胺组、黄连碱组,每组8只;正常组腹腔注射1 m L生理盐水,模型组、洛哌丁胺组、黄连碱组均腹腔注射伊立替康溶液(剂量为350 mg/kg)进行造模。正常组、模型组均灌胃1 m L0.5%CMC-Na溶液,洛哌丁胺组灌胃洛哌丁胺混悬液(0.3 mg/kg),黄连碱组灌胃黄连碱混悬液(30 mg/kg),2次/天,共4天。观察裸鼠腹泻情况、小肠病理改变,ELISA法检测回肠组织中肿瘤坏死因子α(TNF-α)、白介素-6(IL-6)含量,Western blot法检测核因子κB(NF-κB)抑制蛋白α(IκBα)、NF-κB p65蛋白表达。结果正常组均未发生腹泻,模型组、洛哌丁胺组及黄连碱组均出现腹泻;与模型组比较,洛哌丁胺组、黄连碱组2~3分腹泻发生率及腹泻评分均明显下降(P<0.05,P<0.01)。洛哌丁胺组回肠破坏程度较模型组稍减轻,差异无统计学意义(P>0.05),黄连碱组裸鼠回肠黏膜损伤程度较模型组及洛哌丁胺组均明显减轻(P<0.01)。与正常组比较,模型组回肠组织中TNF-α、IL-6及NF-κB p65表达均升高(P<0.01),IκBα表达明显降低(P<0.01);与模型组和洛哌丁胺组比较,黄连碱组TNF-α、IL-6及NF-κB p65表达均明显降低(P<0.05,P<0.01),IκBα表达均明显升高(P<0.05,P<0.01)。结论黄连碱可降低伊立替康引起的CID发生率,减轻腹泻程度及回肠黏膜损伤,其机制可能与其上调IκBα表达,抑制NF-κB通路活化,减轻肠道炎症反应有关。

Objective To observe the therapeutic efficacy of coptisine on mice with chemotherapy-induced diarrhea（ CID）,and to study its underlying mechanisms of action. Methods Totally 32 nude mice were randomly divided into the normal group,the model group,the loperamide group,and the coptisine group,8 in each group. Irinotecan solution（ 350 mg/kg） was injected into the abdominal cavity to establish CID model to mice of all groups except the normal group. Physiological saline（ 1 m L） was injected into the abdominal cavity of mice in the normal group. Mice in the coptisine group were administered with coptisine（ 30 mg/kg） by gastrogavage. Mice in both normal group and model group were administered with1 m L physiological saline（ 0. 5% CMC-Na） by gastrogavage. Mice in the loperamide group were administered with loperamide（ 0. 3 mg/kg） by gastrogavage. All treat ments were performed twice per day for a total of 4 days. Diarrhea and pathological changes of small intestine were observed. Contents of cytokines（ TNF-α and IL-6） in ileum were detected using ELISA.Expressions of nuclear factor-κB α arrestin（ IκBα） and nuclear factor-κB p65（ NF-κB p65） were detected by Western blot.Results No diarrhea occurred in naked mice of the normal group. But diahhrea occurred in the rest 3 groups. The incidence of grade Ⅱ-Ⅲ diarrhea and diarrhea score were lower in the loperamide group and the coptisine group than in the model group（P〈0. 05,P〈0. 01）. The destruction of the ileum were slightly ameliorated in the loperamide group than in the model group,but with no statistical difference（P〉0. 05）. The degree of ileum mucosal damage in the coptisine group was significantly lessened,as compared with that in the model group and the loperamide group（P〈0. 01）. Compared with the normal group,the expressions of TNF-α and IL-6,NF-κB p65 in the model group increased significantly（P〈0. 01）,IκBα expression decreased significantly（P〈0. 01）. Compared with the model group and the loperamide group,the expressions of TNF-α and IL-6,NF-κB p65 in the coptisine group were significantly reduced（P〈0. 05,P〈0. 01）,and the expression of IκBαincreased significantly（P〈0. 01）. Conclusion Coptisine could reduce the incidence of CID induced by irinotecan,attenuate the degree of diarrhea and ileum mucosal damage,and its mechanisms might be associated with up-regulating IκBα expression,inhibiting the activation of NF-κB signaling pathway,and attenuating intestinal inflammatory response.