Supplementary Material for: Transcriptomic Analysis Reveals that Atf3/c-Jun/Lgals3 axis is associated with Central Diabetes Insipidus after Hypothalamic Injury

Background: Hypothalamic injury causes several complicated neuroendocrine-associated disorders, such as water-electrolyte imbalance, obesity, and hypopituitarism. Among these, central diabetes insipidus (CDI), characterized by polyuria, polydipsia, low urine specific gravity, and deficiency of arginine vasopressin contents, is a typical complication after hypothalamic injury. Methods: CDI was induced by hypothalamic pituitary stalk injury in male animals. Behavioral parameters and blood sample were collected to evaluate the characteristics of body fluid metabolism imbalance. The brains were harvested for high-throughput RNA sequencing and immunostaining to identify pathophysiological changes in corresponding hypothalamic nuclei. Results: Based on transcriptomic analysis, we demonstrated the upregulation of the Atf3/c-Jun axis and identified Lgals3, a microglial activation related gene, as the most significant target gene in response to the body fluid imbalance in CDI. Furthermore, we found that the microglia possessed elevated phagocytic ability, which could promote the elimination of arginine vasopressin neurons after hypothalamic injury. Conclusion: Our findings suggested that the Atf3/c-Jun/Lgals3 axis was associated with the microglial activation, and might participate in the loss of functional arginine vasopressin neurons in CDI after hypothalamic injury.

背景：下丘脑损伤可引发多种复杂的神经内分泌相关疾病，如水电解质紊乱、肥胖及垂体功能减退症。其中，以多尿、烦渴、低尿比重及精氨酸加压素含量缺乏为特征的中枢性尿崩症（central diabetes insipidus, CDI），是下丘脑损伤后的典型并发症。
方法：通过对雄性动物实施下丘脑垂体柄损伤构建CDI模型。收集行为学参数与血液样本，以评估体液代谢失衡的特征；获取脑组织进行高通量RNA测序与免疫染色，以明确对应下丘脑核团的病理生理改变。
结果：通过转录组学分析，我们证实了Atf3/c-Jun信号轴的上调，并鉴定出与小胶质细胞激活相关的基因Lgals3为CDI体液失衡应答中最显著的靶基因。进一步研究发现，小胶质细胞的吞噬能力增强，可促进下丘脑损伤后精氨酸加压素能神经元的清除。
结论：本研究结果表明，Atf3/c-Jun/Lgals3信号轴与小胶质细胞激活相关，可能参与下丘脑损伤后CDI模型中功能性精氨酸加压素能神经元的丢失过程。