Identification of arginase in human placental villi
Identification of arginase in human placental villi
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DOI：
10.1016/j.placenta.2006.03.015
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发表时间：
2007-02-01
期刊：
影响因子：
3.8
通讯作者：
Aso, T.
中科院分区：
文献类型：
--
作者：
Ishikawa, T.;Harada, T.;Aso, T.
L-精氨酸是精氨酸酶和一氧化氮合酶的共同底物。精氨酸酶将L精氨酸转化为尿素和鸟氨酸，鸟氨酸是产生细胞增殖所需多胺的主要前体。人胎盘合体滋养层细胞表达内皮型一氧化氮合酶(ENOS)，但精氨酸酶的表达尚未完全阐明。本研究采用免疫组织化学、RT-PCR和免疫印迹方法研究精氨酸酶-I(A-I)和精氨酸酶-II(A-II)在早孕和足月人胎盘绒毛中的表达和分布规律。测定胎盘绒毛组织中精氨酸酶活性。免疫组织化学显示精氨酸酶亚型在妊娠过程中的分布模式不同：A-I仅在细胞滋养层细胞中表达，而A-II在细胞滋养层细胞和合体滋养层细胞中均有表达。RT-PCR和Western印迹分析显示A-I和A-II在早孕期和足月人胎盘绒毛中均有表达。A-II的表达和精氨酸酶活性在妊娠早期高于足月。细胞滋养层细胞向合体滋养层细胞的分化可能与L精氨酸代谢有关，其机制可能是通过调节L精氨酸对一氧化氮合酶和A-I的可用性。妊娠早期精氨酸酶活性升高可能通过增加多胺的产生而促进滋养细胞的增殖。这些结果表明，L-精氨酸-鸟氨酸-多胺和L-精氨酸-一氧化氮通路在胎盘的生长发育中起作用。(C)2006爱思唯尔有限公司。保留所有权利。
L-Arginine is the common substrate for arginase and nitric oxide synthase (NOS). Arginase converts L-arginine to urea and ornithine, which is the principal precursor for production of polyamines required for cell proliferation. Human placenta expresses endothelial NOS (eNOS) in syncytiotrophoblasts, but the expression of arginase has not been fully elucidated. Our aim was to investigate the expression and distribution patterns of arginase-I (A-I) and arginase-II (A-II) in human placental villi in the first trimester and at term using immunohistochemistry, RT-PCR and Western blot analysis. The arginase enzyme activity in placental villi was also measured. Immunohistochemistry showed different distribution patterns of the arginase isoforms during gestation: A-I was observed only in cytotrophoblasts, while A-II was observed in both cytotrophoblasts and syncytiotrophoblasts. RT-PCR and Western blot analysis showed expression of A-I and A-II in the first trimester and at term in human placental villi. Expression of A-II and arginase activity was greater in the first trimester than at term. Differentiation of cytotrophoblasts into syncytiotrophoblasts may be associated with L-arginine metabolism through modulation Of L-arginine availability foreNOS and A-I. And elevated arginase activity in the early gestational period may be responsible for proliferation of trophoblasts by increasing polyamines production. These results suggest that the L-arginine-ornithine-polyamine and L-arginine-nitric oxide pathways play a role in placental growth and development. (c) 2006 Elsevier Ltd. All rights reserved.