Behavioral Neuroscience Program, Department of Psychology, Binghamton University, Binghamton, New York.
Alcohol Clin Exp Res. 2019 Apr;43(4):640-654. doi: 10.1111/acer.13963. Epub 2019 Feb 11.
Studies have demonstrated persistent changes in central nervous system (CNS) cytokine gene expression following ethanol (EtOH) exposure. However, the low endogenous expression and short half-lives of cytokines in the CNS have made cytokine protein detection challenging. The goal of these studies was to establish parameters for use of large-molecule microdialysis and sensitive multiplexing technology for the simultaneous detection of brain cytokines, corticosterone (CORT), and EtOH concentrations in the awake behaving rat.
Adult (P75+) male Sprague Dawley rats that were either naïve to EtOH (Experiment 1) or had a history of adolescent chronic intermittent EtOH (CIE; Experiment 2) were given an acute EtOH challenge during microdialysis. Experiment 1 examined brain EtOH concentrations, CORT and a panel of neuroimmune analytes, including cytokines associated with innate and adaptive immunity. The natural time course of changes in these cytokines was compared to the effects of an acute 1.5 or 3.0 g/kg intraperitoneal (i.p.) EtOH challenge. In Experiment 2, rats with a history of adolescent CIE or controls exposed to vehicle were challenged with 3.0 g/kg i.p. EtOH during microdialysis in adulthood, and a panel of cytokines was examined in parallel with brain EtOH concentrations and CORT.
The microdialysis procedure itself induced a cytokine-specific response that replicated across studies, specifically a sequential elevation of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and IL-10. Surprisingly, acute EtOH did not significantly alter this course of cytokine fluctuations in the hippocampus. However, a history of adolescent CIE showed drastic effects on multiple neuroimmune analytes when rechallenged with EtOH as adults. Rats with a history of adolescent EtOH displayed a severely blunted neuroimmune response in adulthood, evinced by suppressed IL-1β, IL-10, and TNF-α.
Together, these findings provide a methodological framework for assessment of cytokine release patterns, their modulation by EtOH, and the long-lasting changes to neuroimmune reactivity evoked by a history of adolescent CIE.
研究表明，在乙醇（EtOH）暴露后，中枢神经系统（CNS）细胞因子基因表达会发生持续变化。然而，CNS 中细胞因子的内源性表达水平低且半衰期短，使得细胞因子蛋白的检测具有挑战性。这些研究的目的是为使用大分子微透析和敏感的多重分析技术建立参数，以用于在清醒活动的大鼠中同时检测脑细胞因子、皮质酮（CORT）和 EtOH 浓度。
成年（P75+）雄性 Sprague Dawley 大鼠，或在实验 1 中对 EtOH 无反应，或在实验 2 中有青少年慢性间歇性 EtOH（CIE）史，在微透析期间接受急性 EtOH 挑战。实验 1 检查了脑 EtOH 浓度、CORT 和一组神经免疫分析物，包括与先天和适应性免疫相关的细胞因子。将这些细胞因子自然变化的时间过程与急性 1.5 或 3.0 g/kg 腹腔（i.p.）EtOH 挑战的影响进行了比较。在实验 2 中，有青少年 CIE 史或接受载体暴露的大鼠在成年期接受 3.0 g/kg i.p. EtOH 微透析时接受挑战，并同时平行检查了一组细胞因子，以及脑 EtOH 浓度和 CORT。
微透析过程本身会引起细胞因子特异性反应，这种反应在两项研究中都得到了复制，具体表现为白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）和 IL-10 的顺序升高。令人惊讶的是，急性 EtOH 并没有显著改变海马中细胞因子波动的这种过程。然而，青少年 CIE 的病史在成年时再次用 EtOH 挑战时对多种神经免疫分析物产生了剧烈影响。有青少年 EtOH 病史的大鼠在成年时表现出严重的神经免疫反应迟钝，表现为 IL-1β、IL-10 和 TNF-α 的抑制。
综上所述，这些发现为评估细胞因子释放模式及其被 EtOH 调节的情况以及青少年 CIE 病史引起的神经免疫反应的持久变化提供了方法学框架。
