Basic Neuroscience Division, Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, MA, USA.
Lurie Center for Autism, Department of Psychiatry, Harvard Medical School, Massachusetts General Hospital, Lexington, MA, USA.
Neuropsychopharmacology. 2018 Feb;43(3):482-491. doi: 10.1038/npp.2017.243. Epub 2017 Oct 6.
Increasing evidence suggests a role for inflammation in neuropsychiatric conditions, including autism spectrum disorder (ASD). Previous work in rodents has established that immune activation during critical developmental periods can cause phenotypes that reproduce core features of ASD, including decreased social interaction, aberrant communication, and increased repetitive behavior. In humans, ASD is frequently associated with comorbid medical conditions including sleep disorders, motor hyperactivity, and seizures. Here we use a 'two-hit' immune-activation paradigm to determine whether perinatal immune activation can also produce these comorbid features in mice. In this paradigm, we treated timed-pregnant mice with polyinosinic:polycytidylic acid (Poly I:C), which simulates a viral infection, on gestational day 12.5 according to an established maternal immune activation regimen. A subset of the offspring also received a second 'hit' of lipopolysaccharide (LPS), which simulates a bacterial infection, on postnatal day 9. At 6 weeks of age, mice were implanted with wireless telemetry transmitters that enabled continuous measurements of electroencephalography (EEG), electromyography (EMG), locomotor activity, and subcutaneous temperature. Effects at 7 and 12 weeks of age were compared. Both prenatal Poly I:C and postnatal LPS produced changes in locomotor activity and temperature patterns, increases in slow-wave sleep, and shifts in EEG spectral power, several of which persisted at 12 weeks of age. Postnatal LPS also produced persistent increases in spontaneous bursts of epileptiform activity (spike-wave discharges) that occurred predominantly during sleep. Our findings demonstrate that early-life immune activation can lead to long-lasting physiologic perturbations that resemble medical comorbidities often seen in ASD and other neuropsychiatric conditions.
越来越多的证据表明炎症在神经精神疾病中起作用,包括自闭症谱系障碍(ASD)。以前在啮齿动物中的研究已经证实,在关键的发育时期进行免疫激活会导致表现型类似于 ASD 的核心特征,包括社交互动减少、交流异常和重复行为增加。在人类中,ASD 通常与睡眠障碍、运动过度活跃和癫痫等合并症相关。在这里,我们使用“双打击”免疫激活范式来确定围产期免疫激活是否也会在小鼠中产生这些合并症特征。在该范式中,我们根据既定的母体免疫激活方案,在妊娠第 12.5 天用聚肌胞苷酸(Poly I:C)处理定时怀孕的小鼠,模拟病毒感染。一部分后代还在出生后第 9 天接受脂多糖(LPS)的第二次“打击”,模拟细菌感染。在 6 周龄时,将小鼠植入无线遥测发射器,以实现对脑电图(EEG)、肌电图(EMG)、运动活动和皮下温度的连续测量。比较了 7 周和 12 周龄时的效果。产前 Poly I:C 和产后 LPS 均导致运动活动和温度模式发生变化、慢波睡眠增加以及 EEG 频谱功率发生转变,其中一些变化持续到 12 周龄。产后 LPS 还导致自发性癫痫样活动(棘波放电)的爆发持续增加,主要发生在睡眠期间。我们的研究结果表明,早期生活中的免疫激活会导致持续时间较长的生理紊乱,这些紊乱类似于 ASD 和其他神经精神疾病中常见的合并症。