摘要
【目的】从体外和体内研究Lactobacillus animalis LGM对Th细胞分化转录因子T-bet、GATA-3、ROR-γt和Foxp3的调节作用,以及探究L.animalis LGM对小鼠结肠炎的影响。【方法】本试验采用改良型的Hungate滚管技术从猪结肠内容物中分离一株L.animalis LGM,根据其16S rRNA序列进行鉴定。收集L.animalis LGM培养液上清,与细菌脂多糖(LPS,2μg/mL)同时孵育Caco-2细胞24 h,体外研究L.animalis LGM对Caco-2细胞内Th细胞分化转录因子(T-bet,GATA3,ROR-γt和Foxp3)mRNA表达的影响;配制L.animalis LGM细菌悬液,研究L.animalis LGM灌胃对DSS诱导结肠炎小鼠症状及结肠Th细胞分化转录因子和细胞因子(IFN-γ,IL-4,IL-17和IL-10)mRNA表达的影响,表达结果采用荧光定量PCR法检测。【结果】与对照组相比,L.animalis LGM培养液上清显著上调Caco-2细胞内ROR-γt与Foxp3 mRNA表达(P<0.05),显著下调GATA3、IL-4、IL-17和TGF-βmRNA表达(P<0.05)。L.animalis LGM灌胃显著上调小鼠结肠内ROR-γt和Foxp3的表达(P<0.05),显著降低了促炎因子IL-4和IL-17的表达(P<0.05),阻止了小鼠结肠长度缩短(P<0.05)。【结论】猪肠道分离L.animalis LGM表现出对Th细胞分化转录因子的选择性调节,显著上调Caco-2细胞及结肠炎小鼠ROR-γt与Foxp3 mRNA表达。降低DSS诱导结肠炎小鼠炎症水平,对DSS诱导结肠炎起保护作用,有助于维护肠道环境稳态。
[Objective]Investigating the relationship between Lactobacillus animalis LGM and transcription factors(T-bet,GATA3,ROR-γt and Foxp3)gene expressions in vivo or in vitro and observing the effects of L.animalis LGM gavage on DSS-induced colitis.[Methods]L.animalis LGM was isolated from pig colon contents using Hungate rolling tube technique.Bacterial supernatants were extracted and incubated Caco-2 cells with LPS(2μg/mL)simultaneously.Bacterial suspension was adjusted to 1×109 CFU/0.2 mL and gavaged to DSS-induced mice.Gene expressions of transcription factors(T-bet,GATA-3,ROR-γt and Foxp3)and intracellular cytokines(IL-4,IL-17,INF-γand IL-10)were analyzed by real-time PCR.[Results]In Caco-2 cells culture experiment,compared to control and LPS groups,L.animalis LGM supernatants treatment significantly downregulated the GATA-3,IL-4,IL-17 and TGF-βgene expressions and upregulated Foxp3 and ROR-γt gene expressions(P<0.05).In DSS-induced colitis mice,compared to the DSS group,L.animalis LGM administration restored the colonic length and increased ROR-γt and Foxp3 gene expressions(P<0.05).[Conclusion]L.animalis LGM isolated from pig colon contents in the present study have distinctive effects on transcription factors.ROR-γt and Foxp3 expressions were significantly upregulated both in Caco-2 cells and DSS-induced colitis mice.L.animalis LGM showed protection on DSS-induced colitis and gut inflammation.
作者
程颍州
慕春龙
朱伟云
Yingzhou Cheng;Chunlong Mu;Weiyun Zhu(National Center for International Research on Animal Gut Nutrition,Laboratory of Gastrointestinal Microbiology,Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,Jiangsu Province,China)
出处
《微生物学报》
CAS
CSCD
北大核心
2019年第9期1765-1777,共13页
Acta Microbiologica Sinica
基金
国家自然科学基金(31430082)~~
