School of Biomedical Sciences & Pharmacy, The University of Newcastle Callaghan, NSW, 2308, Australia.
Hunter Medical Research Institute, New Lambton Heights, NSW, Australia.
J Neuroinflammation. 2024 Jun 15;21(1):158. doi: 10.1186/s12974-024-03150-3.
Respiratory infections are one of the most common causes of illness and morbidity in neonates worldwide. In the acute phase infections are known to cause wide-spread peripheral inflammation. However, the inflammatory consequences to the critical neural control centres for respiration have not been explored. Utilising a well characterised model of neonatal respiratory infection, we investigated acute responses within the medulla oblongata which contains key respiratory regions. Neonatal mice were intranasally inoculated within 24 h of birth, with either Chlamydia muridarum or sham-infected, and tissue collected on postnatal day 15, the peak of peripheral inflammation. A key finding of this study is that, while the periphery appeared to show no sex-specific effects of a neonatal respiratory infection, sex had a significant impact on the inflammatory response of the medulla oblongata. There was a distinct sex-specific response in the medulla coincident with peak of peripheral inflammation, with females demonstrating an upregulation of anti-inflammatory cytokines and males showing very few changes. Microglia also demonstrated sex-specificity with the morphology of females and males differing based upon the nuclei. Astrocytes showed limited changes during the acute response to neonatal infection. These data highlight the strong sex-specific impact of a respiratory infection can have on the medulla in the acute inflammatory phase.
呼吸道感染是全球新生儿疾病和发病的最常见原因之一。在急性期，感染已知会引起广泛的外周炎症。然而，对于呼吸的关键神经控制中心的炎症后果尚未得到探索。利用一种经过充分特征描述的新生儿呼吸道感染模型，我们研究了包含关键呼吸区域的延髓中的急性反应。新生小鼠在出生后 24 小时内通过鼻腔接种，接种肺炎衣原体或假感染，然后在出生后第 15 天（外周炎症高峰期）收集组织。这项研究的一个重要发现是，尽管在外周似乎没有新生儿呼吸道感染的性别特异性影响，但性别对延髓的炎症反应有显著影响。在与外周炎症高峰期相一致的延髓中存在明显的性别特异性反应，雌性表现出抗炎细胞因子的上调，而雄性则几乎没有变化。小胶质细胞也表现出性别特异性，雌性和雄性的形态因细胞核而异。星形胶质细胞在急性感染反应中表现出有限的变化。这些数据强调了呼吸道感染在急性炎症期对延髓的强烈性别特异性影响。
