Chisaka Hiroshi, Johnstone Jim F, Premyslova Marina, Manduch Zuzka, Challis John R G
CIHR Group in Development and Fetal Health, Department of Physiology and Obstetrics, Gynecology and Medicine, University of Toronto, Toronto, Ontario, Canada.
J Soc Gynecol Investig. 2005 Jul;12(5):303-9. doi: 10.1016/j.jsgi.2005.02.003.
11Beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) is thought to act as a placental barrier protecting the fetus from high levels of maternal cortisol. On the other hand, intrauterine infection is one of the main causes of preterm birth and adverse fetal outcome, and pro-inflammatory cytokines may contribute to these adverse effects. However, the effect of pro-inflammatory cytokines on 11beta-HSD2 is still not clear. Therefore, we have evaluated the effect of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) on 11beta-HSD2 in cultured human placental trophoblast and in human choriocarcinoma JEG-3 cells.
Placental trophoblast cells were isolated from human term placenta. Placental trophoblast cells and JEG-3 cells were treated with TNF-alpha (0.1-10 ng/mL) or IL-1beta (0.1-10 ng/mL). Real-time reverse transcription polymerase chain reaction and Western blot were used to study the regulation of 11beta-HSD2 expression. 11beta-HSD2 activity was determined by measuring the rate of cortisol to cortisone conversion in the culture medium using thin-layer chromatography (TLC).
In placental trophoblast, TNF-alpha and IL-1beta down-regulated 11beta-HSD2 mRNA expression and activity (both P <.05). The protein level was decreased only with IL-1beta (P <.05). In JEG-3 cells, 11beta-HSD2 mRNA was decreased by TNF-alpha but up-regulated by IL-1beta, with no significant change in protein expression and activity.
Our results suggest caution in interpreting data using JEG-3 cells. However, our studies with primary trophoblast suggest that TNF-alpha and IL-1beta may increase the amount of cortisol crossing to the placenta and fetal circulation by attenuating 11beta-HSD2 activity, potentially contributing to preterm labor and altered fetal outcome in uterine infection.
2型11β-羟基类固醇脱氢酶（11β-HSD2）被认为是一种胎盘屏障，可保护胎儿免受母体高水平皮质醇的影响。另一方面，宫内感染是早产和不良胎儿结局的主要原因之一，促炎细胞因子可能导致这些不良影响。然而，促炎细胞因子对11β-HSD2的影响仍不清楚。因此，我们评估了肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β）对培养的人胎盘滋养层细胞和人绒毛膜癌JEG-3细胞中11β-HSD2的影响。
从足月人胎盘中分离出胎盘滋养层细胞。胎盘滋养层细胞和JEG-3细胞用TNF-α（0.1-10 ng/mL）或IL-1β（0.1-10 ng/mL）处理。采用实时逆转录聚合酶链反应和蛋白质印迹法研究11β-HSD2表达的调节。使用薄层色谱法（TLC）通过测量培养基中皮质醇向可的松的转化速率来测定11β-HSD2活性。
在胎盘滋养层细胞中，TNF-α和IL-1β下调了11β-HSD2 mRNA表达和活性（均P<.05）。仅IL-1β使蛋白质水平降低（P<.05）。在JEG-3细胞中，TNF-α使11β-HSD2 mRNA减少，但IL-1β使其上调，蛋白质表达和活性无显著变化。
我们的结果提示在使用JEG-3细胞解释数据时应谨慎。然而，我们对原代滋养层细胞的研究表明，TNF-α和IL-1β可能通过减弱11β-HSD2活性增加进入胎盘和胎儿循环的皮质醇量，这可能导致早产和子宫感染时胎儿结局改变。
