摘要
目的探讨孕期维生素A(VA)缺乏对LPS诱导的仔鼠肠上皮屏障功能障碍的影响。方法构建孕期开始的VA正常(VAN)和VA缺乏(VAD)母鼠模型,其子代(仔鼠)于6周龄时给予脂多糖(LPS)灌胃诱导肠道感染。高效液相色谱法(HPLC)检测血清视黄醇水平;ELISA试剂盒检测仔鼠血清二胺氧化酶(DAO)浓度;采用RT-PCR和Western blot技术测定RA受体(RARβ)、Toll样受体4和紧密连接蛋白ZO-2的变化。结果 VA营养水平与LPS处理均是血清视黄醇的影响因素(P<0.000 1和P=0.035 9),但影响血清视黄醇水平的主要因素是VA营养水平(P<0.000 1)。同时,VA水平与LPS处理也均是血清DAO水平的影响因素(P=0.048 1和P<0.000 1),但LPS是引起DAO水平升高的主要因素(P<0.000 1)。此外,VAD仔鼠结肠黏膜组织中的RARβ、TLR4和ZO-2的mRNA和蛋白表达水平均较VAN组显著降低。LPS处理后,RARβ的表达水平在VAN组进一步降低,VAD仔鼠结肠黏膜组织中TLR4和ZO-2的表达水平始终低于VAN组。结论孕期开始的持续的VA缺乏主要降低血清视黄酸水平及ZO-2的表达,LPS处理上调血清DAO水平及肠上皮细胞TLR4的表达,而RARβ的表达水平受到VAD及LPS的交互作用,提示VA缺乏可能会降低仔鼠肠道的天然免疫调节能力,降低肠道屏障功能,从而影响肠道的抗感染能力。
To investigate the effect of vitamin A deficiency from the beginning of gestation on intestinalepithelial barrier function in the offspring with LPS treatment, pregnant rat models of vitamin A normal（VAN） andvitamin A deficiency（VAD） were constructed and the lipopolysaccharide（LPS） was intragastrically administrated tothe pups at 6-week old for inducing their intestinal infection. The levels of serum retinol were detected by highperformance liquid chromatography（HPLC）, and the intestinal epithelial permeability was tested by using theELISA kit of rat serum diamine oxidase（DAO）. The levels of RARβ, TLR4 and ZO-2 mRNA and protein expressionin the mucosal layer of colon tissues were analyzed by real-time PCR and Western blotting. The status of VAnutrition was the main influence factor to the serum retinol level（P〈0.000 1）, though both the VA nutritional leveland LPS treatment were the effect factors to the levels of serum retinol level（P〈0.000 1, P=0.035 9）. Meanwhile, thebonferroni post-tests found that the LPS challenge wasthe major factor leading to increase of serum DAOlevels（P〈0.000 1）, though both the serum retinol leveland LPS treatment were the effect factors to the levelsof DAO（P=0.048 1, P〈0.000 1）. Furthermore, ThePCR and Western blot results showed that both mRNA and protein levels of RARβ, TLR4 and ZO-2 in the mucosal layer of VAD colon tissues were significantly decreasedcompared with those of VAN pups. The LPS infection significantly down-regulated the level of RARβ mRNAexpression in the VAN group, while also statistically decreased the levels of TLR4 and ZO-2 expressions in theVAD colon tissues compared to those of the VAN group. Taken together, sustainable vitamin A deficiency from thebeginning of gestation markably reduces the levels of serum retinal and the expression of ZO-2 in intestinalepithelial cells, while LPS treatment up-regulates the serum DAO concentration and TLR4 expression in theintestinal epithelium. However, the level of RARβ expressio
出处
《免疫学杂志》
CAS
CSCD
北大核心
2017年第10期837-843,849,共8页
Immunological Journal
基金
国家自然科学基金(81070286
81470799)
重庆市渝中区科委项目(20120210)
