基于肠道菌群探讨维生素A缺乏对小鼠肠道屏障及炎症水平的影响  

Effect of vitamin A deficiency on intestinal barrier and inflammation in mice based on intestinal flora

作　　者：周俊明 李敏利[1] 孙博 吴晓尉[1] 王彬[1] 郭美霞[1] 王小敏 ZHOU Jun-ming;LI Min-li;SUN Bo;WU Xiao-wei;WANG Bin;GUO Mei-xia;WANG Xiao-min(Department of Cadre Gastroenterology,General Hospital of Eastern Theater Command,PLA,Nanjing 210002,Jiangsu,China;The Fifth Station Outpatient Department,General Hospital of Eastern Theater Command,PLA,Nanjing 210002,Jiangsu,China)

机构地区：[1]东部战区总医院(原南京军区南京总医院)干部消化内科,南京210002 [2]东部战区总医院第五派驻门诊部,南京210000

出　　处：《医学研究生学报》2021年第1期20-25,共6页Journal of Medical Postgraduates

基　　金：国家自然科学基金(81904041)。

摘　　要：目的肠道菌群失衡与炎症性肠病的炎症反应联系紧密,但维生素A是否通过影响肠道菌群参与肠道屏障和肠道炎症的病理生理过程仍不完全清楚。探究肠道菌群介导的维生素A缺乏(VAD)对小鼠肠道屏障及肠道炎症的影响。方法C57BL/6孕鼠抽签法分成维生素A正常饮食和VAD饮食。将雄性子鼠分为维生素A补充组(VAN组)、VAD组和维生素A缺乏补充组(VADN组),6只/组。VAN组和VAD组:分别自孕鼠VAN、VAD饮食,生后VAN、VAD孕鼠哺乳,断乳后予VAN、VAD饲料至11周龄;VADN组:11周龄VAD组子鼠改予VAN饮食继续喂养8周。评估各组小鼠体重;高效液相色谱法检测各组小鼠血清视黄醇水平;16s基因测序检测各组小鼠肠道菌群;HE染色、q-PCR和Elisa评价各组小鼠肠组织形态和隐窝深度,肠道屏障蛋白(Occludin和ZO-1)mRNA表达水平以及炎症因子(TNF-α和IL-6)蛋白表达水平。结果与VAN相比,VAD组小鼠血清视黄醇水平较VAN组和VADN组显著降低(P<0.01)。与VAN组相比,VAD组小鼠OTUs数量降低。VAD组较VAN组小鼠Chao、Shannon指数数值降低,Simpson指数数值升高(P<0.05)。β多样性-主成分分析(PCoA)坐标显示,组间差异分布离散,其中VAD小鼠细菌群落结构占总变化的46.09%。OUT分布的维恩(Venn)图提示组间菌群分布存在差异。与VAN组比较,VAD组小鼠厚壁菌门与拟杆菌门(F/B)丰度比值上升(P<0.05)。VAN组和VADN组Occludin mRNA表达水平(1.00±0.07、0.96±0.04)较VAD组(0.44±0.02)显著升高(P<0.01);ZO-1 mRNA表达水平(1.00±0.03、1.06±0.03)亦较VAD组(0.64±0.02)显著升高(P<0.01)。而VAN组和VADN组炎症因子TNF-α[(58.75±25.74、74.55±22.47)pg/mg]较VAD组[(210.77±56.13)pg/mg]明显降低(P<0.01),IL-6含量[(28.25±10.74、50.66±12.47)pg/mg]较VAD组[(115.74±21.20)pg/mg]明显降低(P<0.01)。结论VAD会导致小鼠肠道菌群失调,肠上皮黏膜通透性增强,促炎因子分泌增加,加重屏障功能损伤,是VAD导致肠道损伤的机制之�Objective Imbalance of intestinal flora is closely associated with inflammatory response in inflammatory bowel disease,but it is still not fully understood whether vitamin A(VA)participates in intestinal barrier and pathophysiological process of intestinal inflammation through influencing intestinal flora or not.To explore the effect of VA deficiency mediated by intestinal flora on intestinal barrier and intestinal inflammation in mice.Methods C57 BL/6 pregnant mice were divided into VA-normal(VAN)or VA-deficient(VAD)diets by lottery.Immature offspring male mice were divided into VAN group,VAD group and VA deficiency supplement(VADN)group,6 in each group.In VAN and VAD groups,the pregnant mice were fed with VAN and VAD diet.The baby mice were breast-fed until weaning and then fed with VAN/VAD diet to11-week old.In VADN group:the immature offspring mice in 11-week old were fed on VAN diet for 8 weeks.Weight of mice in each group was assessed.The levels of retinol were detected by high performance liquid chromatography(HPLC).16 S gene sequencing was performed to detect intestinal flora of mice in each group.Intestinal tissue morphology and crypt depth,intestinal barrier protein(Occludin and Zo-1)mRNA expression levels,and inflammatory factors(TNF-α and IL-6)protein expression levels were assessed by HE staining,Q-PCR and Elisa.Results The level of serum retinol in VAD group was significantly lower than that in VAN group and VADN group(P<0.01).Compared with the VAN group,the number of OTUs in the VAD group was reduced.The values of Chao and Shannon indexes in VAD group were lower than those in VAN group,while those of Simpson index were higher(P<0.05).The β-diversity principal component analysis(PCoA)coordinates showed that the distribution of differences between groups was discrete,and the bacterial community structure of VAD mice accounted for 46.09%in the total changes.The Venn diagram of OUT distribution indicated that there were differences in the microflora distribution between groups.Compared with VAN group

关 键 词：维生素A 肠道菌群 肠道屏障 肠道炎症 

分 类 号：R285.5[医药卫生—中药学]