基于STAT3/SREBP1介导的脂质代谢探讨乌梅丸防治结肠炎相关结直肠癌作用机制

Regulatory mechanism of Wumei Pills on colitis-associated colorectal cancer via STAT3/SREBP1 for lipid metabolism

目的:探讨乌梅丸防治结肠炎相关结直肠癌(CAC)的潜在作用机制。方法:36只C57BL/6J小鼠随机分为空白组、模型组、乌梅丸组。通过偶氮甲烷(AOM)和葡聚糖硫酸钠(DSS)联合应用,建立CAC动物模型。第一循环DSS结束1周后,乌梅丸组小鼠予乌梅丸(6 g·kg^(-1)·d^(-1))灌胃,空白组、模型组小鼠给予等体积0.9%氯化钠溶液灌胃,连续给药8周。在第10周结束时计算小鼠存活率、肿瘤数量、结肠长度等;HE染色观察结肠组织病理学改变;q-PCR检测小鼠结肠组织中白介素(IL)-6、IL-1β、肿瘤坏死因子(TNF-α)mRNA水平;Western Blot检测固醇调节元件结合蛋白-1(SREBP1)信号转导和转录激活因子3(STAT3)及p-STAT3的表达;使用超高效液相色谱和串联质谱(UPLC-MS/MS)检测小鼠血清脂质代谢物,使用多变量统计工具筛选血清代谢物的变化。结果:乌梅丸组可提高CAC小鼠存活率,减少肿瘤数量(P<0.05),缩小肿瘤体积,改善结肠病理损伤,降低CAC小鼠结肠组织中炎症因子IL-6、IL-1β、TNF-α的水平(P<0.01,P<0.05);乌梅丸能显著下调SREBP1和p-STAT3的表达(P<0.05);靶向脂质代谢组学显示29种与CAC相关脂质代谢物能够被乌梅丸所回调。结论:乌梅丸能有效防治CAC,其机制可能与STAT3/SREBP1介导的脂质代谢相关。

Objective:To observe the effect of Wumei Pills on colitis-associated colorectal cancer(CAC)and explore its potential mechanism of action.Methods:Thirty-six C57BL/6J mice were randomly divided into a blank group,model group and Wumei Pills group.CAC model was established by the combination of azoxymethane(AOM)and dextran sodium sulfate(DSS).One week after the end of the first cycle of DSS,mice in the blank and model groups were treated with equal volume of normal saline,and mice in the Wumei Pills group were infused with Wumei ills(6 g·kg^(-1)·d^(-1))and administered for 8 weeks.Survival rate,tumor number,and colon length were calculated at the end of week 10;Colon histopathological changes were observed by HE staining;The levels of interleukin(IL)-6,IL-1β,and tumor necrosis factor-α(TNF-α)mRNA in mouse colon tissues were measured by q-PCR;Western Blot detected the expression of sterol-regulatory element-binding protein-1(SREBP1)signaling and activator of transcription 3(STAT3)and p-STAT3;Mice serum lipid metabolites were detected using ultra-highperformance liquid chromatography and tandem mass spectrometry(UPLC-MS/MS),changes in serum metabolites were screened using multivariate statistical tools.Results:Wumei Pills group improved the survival rate of the CAC mice,reduced the number of tumors(P<0.05)and tumor volume,relieved the pathological damage of colon tissues,and significantly reduce the levels of IL-6,IL-1β and TNF-α in the colon tissue of CAC mice(P<0.01,P<0.05);Wumei Pills group significantly downregulated the expression of SREBP1 and p-STAT3(P<0.05);targeting lipid metabolomics showed that 29 lipid metabolites related to CAC could be reversed by Wumei Pills,suggesting that Wumei Pills might prevent the development of CAC by regulating lipid metabolism.Conclusion:Wumei Pills can inhibit tumorigenesis and development in CAC mice,and partially regulate lipid metabolism through STAT3/SREBP1 pathway.