Abstract：
Fetal growth restriction (FGR) is a common outcome in human suboptimal gestation and is related to prenatal origins of cardiovascular dysfunction in offspring. Despite this, therapy of human translational potential has not been identified. Using human umbilical and placental vessels and the chicken embryo model, we combined cellular, molecular, and functional studies to determine whether N-acetylcysteine (NAC) and hydrogen sulphide (H2S) protect cardiovascular function in growth-restricted unborn offspring. In human umbilical and placental arteries from control or FGR pregnancy and in vessels from near-term chicken embryos incubated under normoxic or hypoxic conditions, we determined the expression of the H2S gene CTH (i.e. cystathionine γ-lyase) (via quantitative PCR), the production of H2S (enzymatic activity), the DNA methylation profile (pyrosequencing) and vasodilator reactivity (wire myography) in the presence and absence of NAC treatment. The data show that FGR and hypoxia increased CTH expression in the embryonic/fetal vasculature in both species. NAC treatment increased aortic CTH expression and H2S production and enhanced third-order femoral artery dilator responses to the H2S donor sodium hydrosulphide in chicken embryos. NAC treatment also restored impaired endothelial relaxation in human third-to-fourth order chorionic arteries from FGR pregnancies and in third-order femoral arteries from hypoxic chicken embryos. This NAC-induced protection against endothelial dysfunction in hypoxic chicken embryos was mediated via nitric oxide independent mechanisms. Both developmental hypoxia and NAC promoted vascular changes in CTH DNA and NOS3 methylation patterns in chicken embryos. Combined, therefore, the data support that the effects of NAC and H2S offer a powerful mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy. KEY POINTS: Gestation complicated by chronic fetal hypoxia and fetal growth restriction (FGR) increases a prenatal origin of cardiovascular disease in offspring, increasing interest in antenatal therapy to prevent against a fetal origin of cardiovascular dysfunction. We investigated the effects between N-acetylcysteine (NAC) and hydrogen sulphide (H2S) in the vasculature in FGR human pregnancy and in chronically hypoxic chicken embryos. Combining cellular, molecular, epigenetic and functional studies, we show that the vascular expression and synthesis of H2S is enhanced in hypoxic and FGR unborn offspring in both species and this acts to protect their vasculature. Therefore, the NAC/H2S pathway offers a powerful therapeutic mechanism of human translational potential against fetal cardiovascular dysfunction in complicated pregnancy.
摘要：
胎儿生长受限（FGR）是人类次优妊娠的常见结果，与后代心血管功能障碍的产前起源有关。尽管如此,人类翻译潜力的治疗尚未确定。使用人脐和胎盘血管和鸡胚模型，我们结合了细胞，分子，和功能研究，以确定N-乙酰半胱氨酸（NAC）和硫化氢（H2S）是否保护生长受限的未出生后代的心血管功能。在来自对照或FGR妊娠的人脐和胎盘动脉中，以及在常氧或低氧条件下孵育的近期鸡胚的血管中，我们确定了H2S基因CTH（即cystathionineγ-裂合酶）的表达（通过定量PCR），H2S的产生（酶活性），在存在和不存在NAC治疗的情况下，DNA甲基化谱（焦磷酸测序）和血管扩张剂反应性（线肌电图）。数据显示FGR和缺氧增加了两个物种中胚胎/胎儿脉管系统中的CTH表达。NAC治疗增加了鸡胚主动脉CTH表达和H2S产生，并增强了三级股动脉扩张器对H2S供体氢硫化钠的反应。NAC治疗还恢复了FGR妊娠引起的人类三至四阶绒毛膜动脉和低氧鸡胚胎引起的三阶股动脉中受损的内皮舒张。这种NAC诱导的对缺氧鸡胚内皮功能障碍的保护作用是通过一氧化氮独立的机制介导的。发育缺氧和NAC均促进鸡胚CTHDNA和NOS3甲基化模式的血管变化。合并,因此,数据支持NAC和H2S的作用提供了人类转化潜力对抗复杂妊娠中胎儿心血管功能障碍的强大机制.关键点：妊娠并发慢性胎儿缺氧和胎儿生长受限（FGR）增加了后代心血管疾病的产前起源，产前治疗的兴趣日益增加，以防止胎儿心血管功能障碍。我们研究了FGR人类妊娠和慢性低氧鸡胚胎中脉管系统中N-乙酰半胱氨酸（NAC）和硫化氢（H2S）之间的影响。组合蜂窝，分子，表观遗传和功能研究，我们表明，在这两个物种的缺氧和FGR未出生后代中，H2S的血管表达和合成均得到增强，这可以保护其血管系统。因此,NAC/H2S途径提供了人类转化潜力对复杂妊娠中胎儿心血管功能障碍的强大治疗机制。
