Sha Cuilee, Van Brunt Trevor, Kudria Jacob, Schmidt Donna, Yurovsky Alisa, Bandovic Jela, Giarrizzo Michael, Lin Joyce, Tsirka Styliani-Anna, Bialkowska Agnieszka B, Wollmuth Lonnie P, Speer Esther M, Hsieh Helen
Renaissance School of Medicine, Stony Brook, New York, United States of America.
Center for Nervous System Disorders, SUNY-Stony Brook, Stony Brook, New York, United States of America.
PLoS One. 2025 May 30;20(5):e0323626. doi: 10.1371/journal.pone.0323626. eCollection 2025.
Necrotizing enterocolitis (NEC) is an inflammatory gastrointestinal process that afflicts approximately 10% of preterm infants born in the United States each year, with a mortality rate of 30%. NEC severity is graded using Bell's classification system, from stage I mild NEC to stage III severe NEC. Over half of NEC survivors present with neurodevelopmental impairment during adolescence, a long-term complication that is poorly understood. Although multiple animal models exist, none prospectively controls for NEC severity. We bridge this knowledge gap by characterizing a graded murine model of NEC and studying its relationship with neuroinflammation across a range of NEC severities. Postnatal day 3 (P3) C57BL/6 mice were fed a formula containing different concentrations (0% control, 0.25%, 1%, 2%, and 3%) of dextran sodium sulfate (DSS). P3 mice were fed every 3 hours for 72 hours. We collected data on weight gain and behavior (activity, response, body color) during feeding. At the end of feeding, we collected tissues (intestine, liver, plasma, brain) for immunohistochemistry, immunofluorescence, and cytokine and chemokine analysis. Throughout NEC induction, mice fed higher concentrations of DSS died sooner, lost weight faster, and became sick or lethargic earlier. Intestinal characteristics (dilation, color, friability) were worse in mice fed higher DSS concentrations. Histology revealed small intestinal disarray among all mice fed DSS, while higher DSS concentrations resulted in reduced small intestinal cellular proliferation and increased hepatic and systemic inflammation. In the brain, IL-2, G-CSF, and CXCL1 concentrations increased with higher DSS concentrations, and microglial branching in the hippocampus CA1 was significantly reduced in DSS-fed mice. In conclusion, we characterized a novel graded model of NEC that recapitulates the full range of NEC severities. We showed that mild NEC is sufficient to initiate neuroinflammation and microglia activation. This model will facilitate long-term studies on the neurodevelopmental effects of NEC.
坏死性小肠结肠炎（NEC）是一种炎症性胃肠道疾病，每年折磨着美国约10%的早产儿，死亡率为30%。NEC的严重程度采用贝尔分类系统进行分级，从I期轻度NEC到III期重度NEC。超过一半的NEC幸存者在青少年期出现神经发育障碍，这一长期并发症的发病机制尚不清楚。虽然存在多种动物模型，但没有一种能前瞻性地控制NEC的严重程度。我们通过构建一个分级的NEC小鼠模型并研究其在不同NEC严重程度下与神经炎症的关系，填补了这一知识空白。出生后第3天（P3）的C57BL/6小鼠被喂食含有不同浓度（0%对照、0.25%、1%、2%和3%）葡聚糖硫酸钠（DSS）的配方奶。P3小鼠每3小时喂食一次，持续72小时。我们收集了喂食期间体重增加和行为（活动、反应、体色）的数据。喂食结束时，我们收集组织（肠道、肝脏、血浆、大脑）用于免疫组织化学、免疫荧光以及细胞因子和趋化因子分析。在整个NEC诱导过程中，喂食较高浓度DSS的小鼠死亡更早，体重下降更快，且更早出现生病或嗜睡症状。喂食较高DSS浓度的小鼠肠道特征（扩张、颜色、易碎性）更差。组织学检查显示，所有喂食DSS的小鼠小肠均出现紊乱，而较高的DSS浓度导致小肠细胞增殖减少以及肝脏和全身炎症增加。在大脑中，IL-2、G-CSF和CXCL1的浓度随着DSS浓度的升高而增加，喂食DSS的小鼠海马CA1区的小胶质细胞分支明显减少。总之，我们构建了一种新型的分级NEC模型，该模型概括了NEC的全部严重程度范围。我们表明轻度NEC足以引发神经炎症和小胶质细胞激活。该模型将有助于对NEC的神经发育影响进行长期研究。
