《生命科学》 2012, 24(1): 32-36

维生素A缺乏影响肠道屏障功能的研究进展

刘　霞，李廷玉，陈　洁^*

(重庆医科大学附属儿童医院儿童营养研究中心，儿童发育疾病研究省部共建教育部重点实验室，儿科学重点实验室，重庆市儿童发育重大疾病诊治与预防国际科技合作基地，重庆 400014)

摘　要：摘　要：维生素A(vitamin A， VA)在维持肠道黏膜上皮屏障功能的完整性、调节黏膜免疫反应以及抗感染中起到重要的作用。肠道相关树突状细胞(dendritic cells， DCs)可表达合成视黄酸(retinoic acid， RA)所必需的酶(retinal dehydrogenase， RALDH)，合成RA。RA通过诱导T、B细胞产生整合素α4β7、CCR9，使其归巢到肠道，并提高肠道黏膜sIgA的水平。RA可增强天然CD4+T细胞分化为Foxp3+ Treg细胞，抑制Th17细胞的生成。当机体VA缺乏时可降低肠道屏障功能，下调肠道黏膜免疫反应，增加肠道感染性疾病的易感性，容易导致腹泻。针对维生素A在肠道屏障功能的调节作用作一简要概述。
关键词：维生素A；肠道屏障功能；黏膜免疫应答

Progress of vitamin A deficiency affecting on intestinal epithelial barrier function

LIU Xia， LI Ting-Yu， CHEN Jie^*

(Children’s Nutrition Research Center， Key Laboratory of Developmental Diseases in Childhood of Ministry of Education， Key Laboratory of Pediatrics in Chongqing， Chongqing International Science and Technology Cooperation
    Center for Child Development and Disorder， Children’s Hospital of Chongqing Medical University， Chongqing 400014， China)

Abstract: Abstract: Vitamin A plays important roles on maintaining epithelial barrier integrity， regulating mucosal immune function against several infections. Retinoic acid synthesizing enzymes (RALDH) is expressed in the gut-associated dendritic cells to produce RA. RA can up-regulate expression levels of integrin α4β7、CCR9 of T and B lymphocytes， which enhance the T and B lymphocytes preferentially homing to the small intestine and induce secretion of immunoglobulin-A (IgA). RA also promotes the differentiation of native CD4+T cells into Foxp3+ inducible regulatory T cells (Treg)， and represses the proliferation of Th17 cells. Increasing evidences have demonstrated that vitamin A deficiency may decrease intestinal epithelial barrier function and down-regulate intestinal local mucosal immune responses， resulting in increased susceptibility of intestinal infection and risk of diarrhea. The current paper reviewed the regulatory effects of vitamin A on the intestinal barrier function.
Key words: vitamin A; intestinal barrier function; mucosal immune response