维生素A对小鼠造血微环境影响的研究

EFFECTS OF VITAMIN A ON HEMATOPOIETIC MICROENVIRONMENT

目的： 探讨维生素Ａ（ＶＡ）对造血微环境的影响，揭示ＶＡ缺乏影响红系造血的机制。方法：免疫细胞化学（ＳＰ）法检测视黄酸受体（ＲＡＲａ）蛋白，原位杂交技术动态检测原癌基因ｃ－ｊｕｎ、ｃ－ｆｏｓ和粒－单集落刺激因子（ＧＭ－ＣＳＦ）ｍ ＲＮＡ 的表达，检测细胞因子生物活性和基质细胞层粘附能力。结果： （１）全反式视黄酸（ＡＴＲＡ）诱导的小鼠骨髓基质细胞条件培养液（ＢＭＳＣＣＭ）能显著促进红系早期祖细胞（ＢＦＵ－Ｅ）的增殖（Ｐ＜ ０．０１）。（２）ＡＴＲＡ明显促进基质细胞层的粘附能力。（３）ＲＡＲａ 蛋白在实验组和对照组ＢＭＳＣ持续表达，ＡＴＲＡ对其表达水平无影响。（４）实验组ＢＭＳＣ与对照组相比ｃ－ｆｏｓ、ｃ－ｊｕｎ ｍ ＲＮＡ的表达水平在３０ｍ ｉｎ 即有显著性差异（Ｐ＜ ０．０１），持续表达至６０ｍ ｉｎ，１２０ｍ ｉｎ 降至对照组水平。实验组ＧＭ－ＣＳＦｍ ＲＮＡ的表达在３０ｍ ｉｎ，６０ｍ ｉｎ 与对照组水平相比无显著性差别，直至１２０ｍ ｉｎ 才表现出显著性差异（Ｐ＜ ０．０１）。结论： ＶＡ促进小鼠ＢＭＳＣ分泌造血细胞生长因子并增强其粘附能力，通过调节ＢＭＳＣ中ｃ－ｊｕｎ。

Objective: To study the effects of vitamin A on hematopoietic microenvironment and to elucidate the mechanisms of vitamin A deficient anemia. Methods: Immunocytochemistry method and in situ hybridization technique were used to examine the retinoic acid receptor (RARa) and expression of pro oncogene c jun、 c fos and GM CSF mRNA as well as the biological activity of hematopoietic growth factor and adhesive function of BMSC. Results: (1) ATRA induced BMSC supernatant increased the numbers of BFU E clone and ATRA strengthened the adhesive function of BMSC layer. (2) RARa protein continued to express in both the experimental and control groups, ATRA did not affect the expression level of RARa, (3) c jun、 c fos mRNA began to express after 30min and continued until a peak was reached at 60min, both c jun、 c fos decreased repidly and returned to control level at 120min after exposure to ATRA, while GMCSF mRNA was not significantly different compared with the control group until 120min after following ATRA stimulation. Conclusion: Vitamin A can improve their microenvironment by promoting BMSC to secrete hematopoietic growth factors (HGF) and enhancing its adhesive function. The effects of of vitamin A on the amplification and differentiation of BFU E are via changing the expression of c jun、 c fos mRNA in BMSC and further regulating the secretion of HGF.