Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kamigyo-ku, Kyoto, Japan.
Invest Ophthalmol Vis Sci. 2010 May;51(5):2450-8. doi: 10.1167/iovs.09-4618. Epub 2009 Dec 30.
Compounds regulating intracellular thiol redox status, such as N,N-diacetyl-L-cystine dimethylester (NM(2)), were shown to prolong corneal graft survival in a penetrating keratoplasty (PKP) model. However, the effect of NM(2) on hemangiogenesis and lymphangiogenesis has not been investigated. The effect of manipulating ambient thiol redox status on riskier (higher rejection rate) transplantation models, such as limbal graft survival and hemangiogenesis and lymphangiogenesis in a corneal suture model, were investigated.
C57BL/10 mice that received BALB/c corneas were treated by subconjunctival injection of NM(2), and limbal graft survival was assessed. Sutured C57BL/6 received daily intraperitoneal injections of NM(2), glutathione diethylester (GSH-OEt), or PBS. Lymphatic endothelial cell (LEC) and peritoneal mps were treated with NM(2) or GSHOEt, and then VEGFR3, neuropilin-2, podoplanin, and LYVE-1 expression were analyzed. Supernatants were collected for analysis of TNF-alpha and VEGF-A levels by ELISA.
Significantly less cellular infiltration was detected in mice with corneal limbal transplant-treated NM(2)-treated mice. Hemangiogenesis and lymphangiogenesis were suppressed in the NM(2)-treated mice. NM(2) treatment of mps led to reduced levels of VEGFR3, neuropilin-2, podoplanin, and LYVE-1 expression compared with PBS- or GSHOEt- treated mps, lower levels of TNF-alpha, and increased secretion of VEGF. Moreover, NM(2)-treated LECs had reduced levels of LYVE-1 and Prox-1.
Reduction of ambient redox status reduced inflammatory cell infiltrates. Consequently, reduced inflammatory response might have contributed to both the observed prolonged corneal limbal graft survival and the attenuated hemangiogenesis and lymphangiogenesis in cornea.
调节细胞内硫醇氧化还原状态的化合物，如 N,N-二乙酰-L-半胱氨酸二甲酯（NM（2）），已被证明可延长穿透性角膜移植（PKP）模型中的角膜移植物存活期。然而，NM（2）对血管生成和淋巴管生成的影响尚未得到研究。本研究旨在研究调节环境硫醇氧化还原状态对风险更高（排斥率更高）的移植模型的影响，如角膜缝线模型中的角膜缘移植物存活以及血管生成和淋巴管生成。
接受 BALB/c 角膜的 C57BL/10 小鼠通过结膜下注射 NM（2）进行治疗，并评估角膜缘移植物存活情况。接受缝线的 C57BL/6 小鼠每天接受腹腔内注射 NM（2）、谷胱甘肽二乙酯（GSH-OEt）或 PBS。用 NM（2）或 GSHOEt 处理淋巴管内皮细胞（LEC）和腹腔巨噬细胞（mps），然后分析 VEGFR3、神经纤毛蛋白-2、Podoplanin 和 LYVE-1 的表达。通过 ELISA 分析上清液中 TNF-α和 VEGF-A 的水平。
在 NM（2）处理的角膜缘移植物移植小鼠中，检测到的细胞浸润明显减少。NM（2）处理抑制了血管生成和淋巴管生成。与 PBS 或 GSHOEt 处理的 mps 相比，NM（2）处理的 mps 导致 VEGFR3、神经纤毛蛋白-2、Podoplanin 和 LYVE-1 的表达水平降低，TNF-α水平降低，VEGF 分泌增加。此外，NM（2）处理的 LEC 中 LYVE-1 和 Prox-1 的表达水平降低。
降低环境氧化还原状态减少了炎症细胞浸润。因此，炎症反应的减少可能有助于观察到的角膜缘移植物存活期延长以及角膜中血管生成和淋巴管生成的减弱。
