Xu Fannia, Thomas Jennifer D, Goldowitz Dan, Hamre Kristin M
University of British Columbia, Centre for Molecular Medicine and Therapeutics, Vancouver, BC, Canada.
Center for Behavioral Teratology, San Diego State University, San Diego, CA, United States.
Front Neurosci. 2023 Sep 18;17:1203597. doi: 10.3389/fnins.2023.1203597. eCollection 2023.
Fetal alcohol spectrum disorders (FASD) are the leading preventable cause of intellectual disability, providing the impetus for evaluating various potential treatments to ameliorate ethanol's teratogenic effects, particularly in the nervous system. One treatment is the dietary supplement choline which has been shown to mitigate at least some of ethanol's teratogenic effects. The present study was designed to investigate the effects of genetics on choline's efficacy in ameliorating cell death in the developing neural tube. Previously, we examined BXD recombinant inbred mice, and their parental C57BL/6 J (B6) and DBA/2 J strains, and identified strains that were sensitive to ethanol's teratogenic actions. Thus, we used these strains to identify response to choline treatment.
Timed pregnant mice from 4 strains (B6, BXD51, BXD73, BXD2) were given either ethanol or isocaloric maltose-dextrin (5.8 g/kg in two administrations separated by 2 h) with choline at one of 3 doses: 0, 100 or 250 mg/kg. Subjects were exposed via intragastric gavage on embryonic day 9 and embryos were collected 7 h after the initial ethanol administrations. Cell death was analyzed using TUNEL staining in the developing forebrain and brainstem.
Choline ameliorated the ethanol-induced cell death across all 4 strains without causing enhanced cell death in control mice. Choline was effective in both the developing telencephalon and in the brainstem. Both doses diminished cell death, with some differences across strains and brain regions, although the 100 mg/kg dose was most consistent in mitigating ethanol-related cell death. Comparisons across strains showed that there was an effect of strain, particularly in the forebrain at the higher dose.
These results show that choline is effective in ameliorating ethanol-induced cell death at this early stage of nervous system development. However, there were some strain differences in its efficacy, especially at the high dose, providing further evidence of the importance of genetics in influencing the ability of choline to protect against prenatal alcohol exposure.
胎儿酒精谱系障碍(FASD)是导致智力残疾的首要可预防原因,这促使人们评估各种潜在治疗方法以减轻乙醇的致畸作用,尤其是在神经系统方面。一种治疗方法是膳食补充剂胆碱,它已被证明至少能减轻乙醇的部分致畸作用。本研究旨在调查遗传因素对胆碱改善发育中神经管细胞死亡功效的影响。此前,我们研究了BXD重组近交系小鼠及其亲本品系C57BL/6J(B6)和DBA/2J,并确定了对乙醇致畸作用敏感的品系。因此,我们使用这些品系来确定对胆碱治疗的反应。
来自4个品系(B6、BXD51、BXD73、BXD2)的定时怀孕小鼠,给予乙醇或等热量的麦芽糖糊精(5.8 g/kg,分两次给药,间隔2小时),同时给予3种剂量之一的胆碱:0、100或250 mg/kg。在胚胎第9天通过灌胃法使实验对象接触药物,在首次给予乙醇7小时后收集胚胎。使用TUNEL染色法分析发育中的前脑和脑干中的细胞死亡情况。
胆碱改善了所有4个品系中乙醇诱导的细胞死亡,且未在对照小鼠中导致细胞死亡增加。胆碱在发育中的端脑和脑干中均有效。两种剂量均减少了细胞死亡,不同品系和脑区存在一些差异,尽管100 mg/kg剂量在减轻与乙醇相关的细胞死亡方面最为一致。品系间比较表明存在品系效应,尤其是在高剂量时在前脑中。
这些结果表明,胆碱在神经系统发育的这一早期阶段能有效改善乙醇诱导的细胞死亡。然而,其功效存在一些品系差异,尤其是在高剂量时,这进一步证明了遗传因素在影响胆碱预防产前酒精暴露能力方面的重要性。