摘要
本试验旨在揭示桑叶多糖(MLP)对免疫抑制小鼠肠道损伤和微生物多样性的调节作用,初步阐明其作用机制。选择体重(20.0±0.5)g的5周龄雄性BALB/c小鼠60只,随机分为正常对照组(NC组)、环磷酰胺模型组(MC组)、桑叶多糖低剂量组(MLPL组)、桑叶多糖中剂量组(MLPM组)、桑叶多糖高剂量组(MLPH组)和药物对照组(LM组),每组10只小鼠。各组小鼠腹腔注射80 mg/kg BW环磷酰胺(除NC组外),每天1次,连续3 d,以诱导免疫抑制。第4天开始MLPL、MLPM、MLPH和LM组小鼠每天分别灌胃20、40、80 mg/kg BW的MLP和40 mg/kg BW的左旋咪唑,连续给药9 d;NC和MC组小鼠每天灌胃等量饮用水。试验期13 d。采用苏木精-伊红(HE)染色法、定量逆转录PCR(RT-qPCR)法、微生物扩增子法分别测定各组小鼠空肠组织形态学,结肠上皮紧密连接蛋白[闭合蛋白(Occludin)、闭锁小带蛋白-1(ZO-1)、封闭蛋白-5(Claudin-5)]、黏液素2(MUC2)、免疫相关因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-10(IL-10)、转化生长因子-β(TGF-β)]、免疫信号通路相关蛋白[Toll样受体4(TLR4)、髓样分化因子88(MyD88)、核因子-κB p65亚基(p65)]的mRNA表达以及盲肠微生物多样性。结果表明:1)与MC组比较,MLPL、MLPM和MLPH组小鼠空肠病理损伤明显减轻。2)与NC组相比,MC组Claudin-5、ZO-1、Occludin、MUC2的mRNA相对表达量显著降低(P<0.05)。与MC组相比,MLPM、MLPH和LM组Claudin-5、MUC2的mRNA相对表达量显著升高(P<0.05),MLPM和MLPH组Occludin的mRNA相对表达量显著升高(P<0.05),MLPH组ZO-1的mRNA相对表达量显著升高(P<0.05)。3)与NC组相比,MC组TNF-α、IL-1β的mRNA相对表达量显著降低(P<0.05),IL-10、TGF-β的mRNA相对表达量显著升高(P<0.05)。与MC组相比,MLPM、MLPH和LM组TNF-α、IL-1β的mRNA相对表达量升高(P<0.05),MLPL、MLPM、MLPH和LM组IL-10和TGF-β的mRNA相对表达量显著降低(P<0.05)。4)与NC组相比,MC组TLR4、MyD88、p65�
This experiment was conducted to reveal the regulating effects of mulberry leaf polysaccharide(MLP)on intestinal damage and microbial diversity of immunosuppressed mice,and to preliminarily clarify its mechanism.Sixty 5-week-old male BALB/c mice with body weight of(20.0±0.5)g were randomly divided into normal control group(NC group),cyclophosphamide model group(MC group),mulberry leaf polysaccharide low-dose group(MLPL group),mulberry leaf polysaccharide medium-dose group(MLPM group),mulberry leaf polysaccharide high-dose group(MLPH group)and drug control group(LM group),with 10mice in each group.Mice in all groups except NC group were injected intraperitoneally with 80 mg/kg BW cyclophosphamide once a day for three days to establish immunosuppressive model.From the fourth day,mice were administered intragastrically with 20,40 and 80 mg/kg BW of MLP in MLPL,MLPM and MLPH groups and 40 mg/kg BW of levamisole in LM group,continuous administration for 9 days;while the mice in MC and NC groups were administered intragastrically instead with equivalent drinking water.The jejunal histomorphology,colonic epithelium tight junction protein[(Occludin,zonula occludens protein-1(ZO-1)and Claudin-5)],mucin 2(MUC2),immune related factors[tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),interleukin-10(IL-10)and transforming growth factor-β(TGF-β)]and immune signaling pathway related proteins[Toll-like receptor 4(TLR4),myeloid differentiation protein 88(MyD88)and nuclear factor-κB p65 subunit(p65)]mRNA expression and cecal microbial diversity were measured by hematoxylin-eosin(HE)staining,quantitative reverse transcription PCR(RT-qPCR)and microbial amplicon sequencing.The results showed as follows:1)compared with the MC group,the jejunal pathological injury of mice of MLPL,MLPM and MLPH groups was obvious reduced.2)Compared with the NC group,the mRNA relative expression levels of Claudin-5,ZO-1,Occludin and MUC2 of the MC group were significantly decreased(P<0.05).Compared with the MC group,the mRNA relative expressi
作者
陈晓兰
宣嘉颖
王婧
冒玉娟
徐向萍
杨海峰
CHEN Xiaolan;XUAN Jiaying;WANG Jing;MAO Yujuan;XU Xiangping;YANG Haifeng(Jiangsu Agri-Animal Husbandry Vocational College,Taizhou 225300,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2022年第3期1996-2008,共13页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家自然科学基金项目(31702286)
2021年江苏省高校青蓝工程学术带头人资助项目
安徽省科技厅重点研发计划(S202104g01020016)
泰州市科技支撑计划(农业)项目(TN202006)
江苏农牧科技职业学院动物药品科技创新团队(NSF2021TC02)。
关键词
桑叶多糖
肠道损伤
微生物多样性
免疫抑制
环磷酰胺
mulberry leaf polysaccharide
intestinal damage
microbial diversity
immunosuppression
cyclophosphamide
