Neonatal encephalopathy (NE) impairs white matter development and results in long-term neurodevelopmental deficits. Leveraging prior findings of altered neuronal proteins carried by brain-derived extracellular vesicles (EVs) that are marked by a neural-specific cell surface glycoprotein Contactin-2 (CNTN2) in NE infants, the present study aimed to determine the correlation between brain and circulating CNTN2-EVs and whether NE alters circulating CNTN2-EV levels in mice. Brain tissue and plasma were collected from postnatal day (P)7, 10, 11, 15 mice to determine the baseline CNTN2 correlation between these two compartments ( = 4–7/time point/sex). NE was induced in P10 pups. Brain and plasma samples were collected at 1, 3, 6, 24, and 120 h ( = 4–8/time point/sex). CNTN2 from brain tissue and plasma EVs were quantified using ELISA. ANOVA and linear regression analyses were used to evaluate changes and correlations between brain and plasma CNTN2-EVs. In baseline experiments, CNTN2 in brain tissue and plasma EVs peaked at P10 with no sex-difference. Brain and plasma CNTN2-EV showed a positive correlation across early postnatal ages. NE pups showed an elevated CNTN2 in brain tissue and EVs at 1 h and only in brain tissue at 24 h. NE also abolished the positive plasma-brain correlation. The findings establish a link for central CNTN2 and its release into circulation during early postnatal life. The immediate elevation and release of CNTN2 following NE highlight a potential molecular response shortly after a brain injurious event. Our findings further support the utility of circulating brain-derived EVs as a possible bioindicator of NE.

中文翻译：

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新生儿缺氧缺血改变小鼠血浆中脑源性 Contactin-2 阳性细胞外囊泡

新生儿脑病（NE）会损害白质发育并导致长期神经发育缺陷。利用先前在 NE 婴儿中脑源性细胞外囊泡 (EV) 携带的改变的神经元蛋白的发现，这些蛋白以神经特异性细胞表面糖蛋白 Contactin-2 (CNTN2) 为标志，本研究旨在确定大脑和循环之间的相关性。 CNTN2-EV 以及 NE 是否改变小鼠体内循环 CNTN2-EV 水平。从出生后第 7、10、11、15 天的小鼠收集脑组织和血浆，以确定这两个区室之间的基线 CNTN2 相关性（= 4-7/时间点/性别）。在 P10 幼崽中诱导 NE。在 1、3、6、24 和 120 小时（= 4-8/时间点/性别）收集脑和血浆样本。使用 ELISA 对脑组织和血浆 EV 中的 CNTN2 进行定量。使用方差分析和线性回归分析来评估大脑和血浆 CNTN2-EV 之间的变化和相关性。在基线实验中，脑组织和血浆 EV 中的 CNTN2 在 P10 时达到峰值，没有性别差异。大脑和血浆 CNTN2-EV 在出生后早期表现出正相关。 NE幼仔在1小时时脑组织和EVs中显示出CNTN2升高，并且仅在24小时时脑组织中出现CNTN2升高。 NE还消除了血浆-大脑的正相关性。这些发现建立了中枢 CNTN2 及其在产后早期释放到循环中的联系。 NE 后 CNTN2 的立即升高和释放突显了脑损伤事件后不久的潜在分子反应。我们的研究结果进一步支持循环脑源性 EV 作为 NE 可能的生物指示剂的效用。