短期抗生素暴露对氧化偶氮甲烷诱导小鼠结直肠癌前病变相关指征变化的影响  

Effects of short-term antibiotic exposure on changes in indicators related to azomethane-induced colorectal precancerous lesions in mice

作　　者：林嘉玲 何夏梦 蒲芳芳 蒙婷 商正云 胡雯[2] 曾献春[1] Lin Jia-ing;He Xia-meng;Pu Fang-fang;Meng Ting;Shang Zheng-yun;Hu Wen;Zeng Xian-chun(School of Laboratory Medicine,Chengdu Medical College,Chengdu 610500;West China Hospital,Sichuan University,Chengdu 610041;West China School of Public Health,Sichuan University,Chengdu 610041)

机构地区：[1]成都医学院检验医学院,成都610500 [2]四川大学华西医院,成都610041 [3]四川大学华西公共卫生学院,成都610041

出　　处：《中国抗生素杂志》2023年第4期458-465,共8页Chinese Journal of Antibiotics

基　　金：四川省科技厅重点研发项目(No.2019YFS0260)。

摘　　要：目的探讨短期抗生素暴露对氧化偶氮甲烷(Azoxymethane,AOM)诱导小鼠结直肠癌前病变相关指征变化的影响。方法40只3~4周龄SPF级雄性ICR小鼠随机分为4组(10只/组):对照组(Control组)、AOM干预组(AOM组)、抗生素+AOM干预组(Antibiotics+Azoxymethane,AbxAOM组)以及抗生素组(Antibiotics,Abx组)。AbxAOM组和Abx组灌胃抗生素溶液(氨苄西林100 mg/kg+新霉素100 mg/kg+甲硝唑100 mg/kg+万古霉素50 mg/kg+两性霉素B 1 mg/kg),Control组和AOM组灌胃等体积纯水,2次/天,连续14 d。灌胃结束后,AOM组和AbxAOM组腹腔注射AOM溶液(10 mg/kg·bw),Control组和Abx组腹腔注射相应体积的无菌0.9%NaCl溶液,1次/周,连续4周。HE染色观察小鼠结直肠组织病理学改变;RT-qPCR法检测结直肠组织中VCAM-1、ICAM-1、Ki-67、IL-1β、IL-6、TNF-α、VEGF-A、TLR4、MyD88、NF-κB p65及COX-2的mRNA表达水平;免疫组化法观察结直肠组织中Ki-67、NF-κB p65蛋白表达。结果与Control组相比,AOM组小鼠结肠病理组织学评分显著升高(P<0.01),IL-6、TLR4、NF-κB p65及COX-2的mRNA表达显著升高(P<0.05)。与AOM组比较,AbxAOM组异常隐窝灶(Aberrant crypt foci,ACF)数量增多(P<0.05),ICAM-1、IL-1β、NF-κB p65的mRNA表达显著升高(P<0.05)。结论AOM处理可导致结肠病理损伤及ACF形成,可能与TLR4/MyD88/NF-κB信号通路的激活有关。抗生素暴露在短期内有加剧AOM所致结肠损伤和TLR4/MyD88/NF-κB信号通路进一步激活的趋势,但此变化趋势还需在长期实验基础上进一步探讨。Objective To investigate the effect of short-term antibiotic exposure on the changes of azoxymethane(AOM)-induced colorectal precancerous lesions in mice.Methods Forty 3-to 4-week-old SPF-grade male ICR mice were randomly divided into four groups(10 mice/group):Control group(Control group),AOM intervention group(AOM group),antibiotic+AOM intervention group(Antibiotics+Azoxymethane,AbxAOM group),and antibiotic group(Antibiotics,Abx group).The AbxAOM group and the Abx group were administered with antibiotic solution(ampicillin 100 mg/kg+neomycin 100 mg/kg+metronidazole 100 mg/kg+vancomycin 50 mg/kg+amphotericin B 1 mg/kg),The control group and the AOM group was given an equal volume of pure water,twice a day,for 14 consecutive days.After gavage,the AOM group and the AbxAOM group were intraperitoneally injected with AOM solution(10 mg/kg.bw),and the control group and the Abx group were intraperitoneally injected with the corresponding volume of sterile 0.9%NaCl solution,once a week for 4 consecutive weeks.HE staining was used to observe the pathological changes of colorectal tissue in mice.The expression of VCAM-1,ICAM-1,Ki-67,IL-1β,IL-6,TNF-α,VEGF-A,TLR4,MyD88,NF-κB p65,and COX-2 mRNA and the expression of Ki-67 and NF-κB p65 protein in colorectal tissues were detected by RT-qPCR and immunohistochemistry,respectively.Results Compared with the control group,mice in the AOM group had significantly higher colonic pathological histological scores(P<0.01)and significantly higher mRNA expression of IL-6,TLR4,NF-κB p65,and COX-2(P<0.05).Compared with the AOM group,the number of ACF was increased in the AbxAOM group(P<0.05),and the expression of mRNA for ICAM-1,IL-1β,and NF-κB p65 was significantly higher(P<0.05).Conclusion AOM treatment leads to colon pathological damage and ACF formation,which may be related to the activation of TLR4/MyD88/NF-κB signaling pathway.Antibiotic exposure tends to aggravate AOM-induced colon damage and further activate TLR4/MyD88/NF-κB signaling pathway in the short term.However,this

关 键 词：结直肠癌 抗生素 氧化偶氮甲烷 

分 类 号：R965[医药卫生—药理学]