Sacerdoti Flavia, Amaral María M, Zotta Elsa, Franchi Ana M, Ibarra Cristina
Laboratorio de Fisiopatogenia, Departamento de Fisiología, Instituto de Fisiología y Biofísica Bernardo Houssay (IFIBIO Houssay-CONICET), Facultad de Medicina, Universidad de Buenos Aires, 2155 Paraguay street, Piso 6, 1121 Buenos Aires, Argentina.
CEFYBO-CONICET, Universidad de Buenos Aires, 2155 Paraguay Street, Piso 16, 1121 Buenos Aires, Argentina.
Biomed Res Int. 2014;2014:384645. doi: 10.1155/2014/384645. Epub 2014 May 5.
Shiga toxin type 2 (Stx2), a toxin secreted by Shiga toxin-producing Escherichia coli (STEC), could be one of the causes of maternal and fetal morbimortality not yet investigated. In this study, we examined the effects of Stx2 in rats in the early stage of pregnancy. Sprague-Dawley pregnant rats were intraperitoneally (i.p.) injected with sublethal doses of Stx2, 0.25 and 0.5 ng Stx2/g of body weight (bwt), at day 8 of gestation (early postimplantation period of gestation). Maternal weight loss and food and water intake were analyzed after Stx2 injection. Another group of rats were euthanized and uteri were collected at different times to evaluate fetal status. Immunolocalization of Stx2 in uterus and maternal kidneys was analyzed by immunohistochemistry. The presence of Stx2 receptor (globotriaosylceramide, Gb3) in the uteroplacental unit was observed by thin layer chromatography (TLC). Sublethal doses of Stx2 in rats caused maternal weight loss and pregnancy loss. Stx2 and Gb3 receptor were localized in decidual tissues. Stx2 was also immunolocalized in renal tissues. Our results demonstrate that Stx2 leads to pregnancy loss and maternal morbidity in rats in the early stage of pregnancy. This study highlights the possibility of human pregnancy loss and maternal morbidity mediated by Stx2.
2型志贺毒素（Stx2）是由产志贺毒素大肠杆菌（STEC）分泌的一种毒素，可能是尚未被研究的孕产妇和胎儿发病及死亡的原因之一。在本研究中，我们检测了Stx2在妊娠早期大鼠体内的作用。在妊娠第8天（妊娠植入后早期），将亚致死剂量的Stx2（0.25和0.5 ng Stx2/克体重）腹腔注射到Sprague-Dawley妊娠大鼠体内。注射Stx2后分析母鼠体重减轻情况以及食物和水的摄入量。另一组大鼠在不同时间点安乐死并收集子宫以评估胎儿状况。通过免疫组织化学分析Stx2在子宫和母鼠肾脏中的免疫定位。通过薄层色谱法（TLC）观察子宫胎盘单位中Stx2受体（球三糖神经酰胺，Gb3）的存在。亚致死剂量的Stx2导致大鼠母鼠体重减轻和妊娠丢失。Stx2和Gb3受体定位于蜕膜组织中。Stx2在肾组织中也有免疫定位。我们的结果表明，Stx2导致妊娠早期大鼠妊娠丢失和母鼠发病。本研究突出了Stx2介导人类妊娠丢失和母鼠发病的可能性。
