A highly efficient method for constructing indomethacin-peptide conjugates was developed using the natural amino acid tyrosine (Y) as the anchor for indomethacin (Idm). With pH = 6, Idm-YEE conjugate self-assembled in a low critical micelle concentration (CMC, 0.037 mg/mL) and formed a transparent hydrogel (0.4 wt%). The formed Idm-YEE hydrogel presented sustained drug release of indomethacin with a maximum of 40% during first 24 hours, which was superior to the reported Idm-containing supramolecular hydrogel systems. As kept at 4 °C, the Idm-YEE hydrogel showed good storage stability up to 30 days without obvious hydrolysis. As shown by MTT assay, the Idm-YEE hydrogel exhibited good cell compatibility against retinal pigment epithelial cells (ARPE-19) and Human corneal epithelial cells (HCEC). Ocular irritation test (i.e., clinical observations, fluorescein staining and H&E histological analysis) results showed good integrity of corneal architecture and no edema after Idm-YEE hydrogel treatment, which proved its good ocular biocompatibility. Besides, the LPS-stimulated levels of key inflammatory mediators, including NO, PGE₂ and IL-6, were greatly reduced by Idm-YEE hydrogel even in a low concentration (50 μM) in Raw264.7 cells, which indicated its comparable in vitro anti-inflammatory activity to indomethacin. Furthermore, the therapeutic efficacy of Idm-YEE hydrogel was evaluated in endotoxin-induced uveitis (EIU) rabbit model. By treating with dm-YEE hydrogel, the rabbit eyes had significantly lowered inflammation and exudation in the anterior chamber. The results of histological analysis, clinical score, inflammatory cell counts, aqueous protein concentration and immunohistochemical staining also demonstrated its good in vivo therapeutic activity towards ocular inflammation. Therefore, with good ocular biocompatibility and comparable anti-inflammatory effect towards ocular inflammation, the novel indomethacin-tripeptide hydrogel (Idm-YEE) developed in this work provides a potential treatment for anterior uveitis.

中文翻译：

---

一种抑制眼部炎症的新型吲哚美辛三肽水凝胶。

使用天然氨基酸酪氨酸 (Y) 作为吲哚美辛 (Idm) 的锚点，开发了一种构建吲哚美辛-肽缀合物的高效方法。在 pH = 6 时，Idm-YEE 缀合物以低临界胶束浓度（CMC，0.037 mg/mL）自组装并形成透明水凝胶（0.4 wt%）。形成的 Idm-YEE 水凝胶在前 24 小时内表现出最大 40% 的吲哚美辛持续药物释放，优于报道的含有 Idm 的超分子水凝胶系统。在 4°C 下，Idm-YEE 水凝胶显示出良好的储存稳定性，长达 30 天没有明显的水解。MTT实验表明，Idm-YEE水凝胶对视网膜色素上皮细胞（ARPE-19）和人角膜上皮细胞（HCEC）表现出良好的细胞相容性。眼刺激试验（即临床观察、荧光素染色和 H&E 组织学分析）结果显示，Idm-YEE 水凝胶处理后角膜结构完整性良好，无水肿，证明其良好的眼部生物相容性。此外，即使在低浓度（50μ M) 在 Raw264.7 细胞中，表明其体外抗炎活性与吲哚美辛相当。此外，在内毒素诱导的葡萄膜炎 (EIU) 兔模型中评估了 Idm-YEE 水凝胶的治疗效果。通过用 dm-YEE 水凝胶治疗，兔眼显着降低了前房的炎症和渗出。组织学分析、临床评分、炎症细胞计数、水性蛋白浓度和免疫组化染色的结果也证明了其在体内的良好对眼部炎症的治疗活性。因此，由于具有良好的眼部生物相容性和对眼部炎症的类似抗炎作用，这项工作中开发的新型吲哚美辛三肽水凝胶（Idm-YEE）为前葡萄膜炎提供了潜在的治疗方法。