From the Department of Anesthesiology.
McKnight Brain Institute, University of Florida College of Medicine, Gainesville, Florida.
Anesth Analg. 2020 Oct;131(4):1291-1299. doi: 10.1213/ANE.0000000000005097.
Neonatal exposure to sevoflurane induces neurobehavioral and neuroendocrine abnormalities in exposed male rats (generation F0) and neurobehavioral, but not neuroendocrine, abnormalities in their male, but not female, offspring (generation F1). These effects of sevoflurane are accompanied by a hypermethylated neuron-specific K-2Cl (Kcc2) Cl exporter gene in the F0 spermatozoa and the F1 male hypothalamus, while the gene's expression is reduced in the F0 and F1 hypothalamus. We investigated whether inhibition of deoxyribonucleic acid methyltransferases (DNMTs) before paternal sevoflurane exposure could alleviate the anesthetic's F0 and F1 effects.
Sprague-Dawley male rats were anesthetized with 2.1% sevoflurane for 5 hours on postnatal day (P) 5 and mated with control females on P90 to generate offspring. The nonselective DNMT inhibitor decitabine (0.5 mg/kg, intraperitoneally) was administered 30 minutes before sevoflurane exposure. The F0 and F1 male rats were evaluated in in vivo and in vitro tests in adulthood.
Paternal exposure to sevoflurane induced impaired prepulse inhibition of the acoustic startle response and exacerbated corticosterone responses to stress in F0 males and impaired prepulse inhibition of the startle responses in F1 males. These effects were accompanied in both generations by reduced and increased expressions of hypothalamic Kcc2 and Dnmt3a/b, respectively. Decitabine deterred the effects of paternal exposure to sevoflurane in F0 and F1 males.
These results suggest that similar decitabine-sensitive mechanisms regulating expression of multiple genes are involved in the mediation of neurobehavioral abnormalities in sires neonatally exposed to sevoflurane and in their future unexposed male offspring.
新生雄性大鼠接触七氟醚会导致其 F0 代雄性子代出现神经行为和神经内分泌异常,而仅雄性子代出现神经行为异常,雌性子代无异常(F1 代)。七氟醚的这些影响伴随着 F0 代精子和 F1 代雄性下丘脑中神经元特异性 K-2Cl(Kcc2)Cl 外排基因的超甲基化,而该基因在 F0 和 F1 代下丘脑的表达减少。我们研究了在父代接触七氟醚之前抑制脱氧核糖核酸甲基转移酶(DNMTs)是否可以减轻麻醉剂对 F0 和 F1 的影响。
新生第 5 天(P)的 Sprague-Dawley 雄性大鼠用 2.1%七氟醚麻醉 5 小时,并于 P90 日龄与对照雌性大鼠交配以产生子代。非选择性 DNMT 抑制剂地西他滨(0.5mg/kg,腹腔内注射)在接触七氟醚前 30 分钟给予。在成年期对 F0 和 F1 雄性大鼠进行体内和体外测试。
父代接触七氟醚导致 F0 代雄性大鼠的听觉惊跳反应的预脉冲抑制受损,对压力的皮质酮反应加剧,F1 代雄性大鼠的惊跳反应的预脉冲抑制受损。这两代大鼠的下丘脑 Kcc2 和 Dnmt3a/b 的表达分别减少和增加。地西他滨阻止了父代接触七氟醚对 F0 和 F1 代雄性大鼠的影响。
这些结果表明,调节多个基因表达的类似地西他滨敏感机制可能参与了新生雄性大鼠接触七氟醚后神经行为异常的介导作用,以及其未来未暴露的雄性子代的神经行为异常。