University of Wisconsin-Madison, Madison, Wisconsin, United States.
Invest Ophthalmol Vis Sci. 2024 Oct 1;65(12):13. doi: 10.1167/iovs.65.12.13.
The optic nerve head (ONH) is well known to be the initial site of glaucomatous damage; however, the molecular mechanisms initiating this pathology are not fully understood. To further understand the initiating factors in glaucomatous damage we utilized a novel mouse model of glaucoma, B6.EDA+/+ mice, which constitutively express fibronectin containing the extra domain A (FN+EDA). FN+EDA is a known damage-associated molecular pattern (DAMP) that activates Toll-like receptor 4 and elicits a fibro-inflammatory response.
Eyes from B6.EDA+/+ and C57BL/6J mice were evaluated for retinal ganglion cell (RGC) death, retinal nerve fiber layer (RNFL) thickness, and optic nerve (ON) damage at 12 months and 22 months of age. ONH sections were isolated using laser capture microdissection for subsequent RNA-sequencing and Gene Set Enrichment Analysis (GSEA). GSEA results were confirmed using immunohistochemical (IHC) staining.
B6.EDA+/+ mice exhibit significantly higher intraocular pressure, loss of RGCs, thinning of the RNFL, and progressive levels of ON damage at 12 months and 22 months of age compared to C57BL/6J controls. Protein expression of DAMPs FN+EDA and biglycan was significantly increased in B6.EDA+/+ mice compared to C57BL/6J controls. GSEA analysis identified significantly up- and downregulated gene groupings at both 12 months and 22 months of age, and IHC staining at 12 and 18 months of age demonstrated significant increases of IFNα, IFNβ, and pSTAT1 expression in B6.EDA+/+ mice compared to C57BL/6J controls.
Our study characterizes glaucomatous changes to the retina, ON, and ONH over the course of 2 years and identifies novel molecular pathways associated with these pathophysiological changes. These data illustrate the effects of FN+EDA on the fibro-inflammatory response in the aging ONH in a novel mouse model of glaucoma.
众所周知，视神经头（ONH）是青光眼损伤的初始部位；然而，引发这种病变的分子机制尚不完全清楚。为了进一步了解青光眼损伤的起始因素，我们利用了一种新型青光眼小鼠模型，即 B6.EDA+/+ 小鼠，其持续表达含有外显子 A 的纤维连接蛋白（FN+EDA）。FN+EDA 是一种已知的损伤相关分子模式（DAMP），可激活 Toll 样受体 4 并引发纤维炎症反应。
在 12 个月和 22 个月大时，评估 B6.EDA+/+ 和 C57BL/6J 小鼠的视网膜神经节细胞（RGC）死亡、视网膜神经纤维层（RNFL）厚度和视神经（ON）损伤情况。使用激光捕获显微解剖术分离 ONH 切片，用于随后的 RNA 测序和基因集富集分析（GSEA）。使用免疫组织化学（IHC）染色证实 GSEA 结果。
与 C57BL/6J 对照相比，B6.EDA+/+ 小鼠在 12 个月和 22 个月大时表现出明显更高的眼内压、RGC 丧失、RNFL 变薄和进行性的 ON 损伤。与 C57BL/6J 对照相比，B6.EDA+/+ 小鼠 DAMPs FN+EDA 和 biglycan 的蛋白表达明显增加。在 12 个月和 22 个月大时，GSEA 分析确定了明显上调和下调的基因分组，在 12 个月和 18 个月大时，IHC 染色显示 B6.EDA+/+ 小鼠中 IFNα、IFNβ 和 pSTAT1 的表达明显增加与 C57BL/6J 对照相比。
我们的研究描述了在 2 年内视网膜、ON 和 ONH 的青光眼变化，并确定了与这些病理生理变化相关的新分子途径。这些数据说明了 FN+EDA 在新型青光眼小鼠模型中对衰老 ONH 中纤维炎症反应的影响。
