Increased membrane localization of pannexin1 in human corneal synaptosomes causes enhanced stimulated ATP release in chronic diabetes mellitus.
Increased membrane localization of pannexin1 in human corneal synaptosomes causes enhanced stimulated ATP release in chronic diabetes mellitus.
复制标题
pannexin1在人角膜突触体中的膜定位增加导致慢性糖尿病刺激的ATP释放增强。
DOI：
10.1097/md.0000000000005084
复制
发表时间：
2016-12
期刊：
影响因子：
1.6
通讯作者：
Huang Y
中科院分区：
文献类型：
--
作者：
Cui H;Liu Y;Qin L;Wang L;Huang Y
在本研究中，我们调查了中度非胰岛素依赖型糖尿病患者角膜神经末梢的潜在变化。解剖的角膜进行超离心的协议，以获得感觉神经末梢的突触体。在这些神经静脉曲张中，检查了2种主要机制，即，机械敏感性通道pannexin 1和ATP释放的改变对这些终端的刺激。我们假设，改变的细胞位置和泛连接蛋白通道的功能可能有助于改变角膜的机械敏感性，这反过来又可能影响伤口愈合和角膜的主要视觉功能。集中检查泛连接蛋白通道的主要理由是由于其在机械敏感性中的作用以及其糖基化性质。与非糖尿病对照组相比，糖尿病受试者之间的Pannexin 1保持不变。然而，凝集素免疫分析表明，pannexin 1是显着更多的糖尿病角膜突触体糖基化。膜生物素化检测显示pannexin 1的膜定位在糖尿病样品中显著增强。此外，与从血糖正常受试者的角膜静脉曲张中获得的pannexin 1相比，糖-pannexin 1的S-亚硝基化显著降低。与对照组相比，糖尿病角膜突触体在氯化钾刺激后显示出增强的ATP释放。此外，我们已经表明，pannexin 1的S-亚硝基化实际上降低了pannexin 1释放ATP的能力。因此，与周围神经非常相似，角膜神经在慢性糖尿病中也表现出增加的超敏性。所有这些病理变化可累积改变糖尿病患者的角膜功能。
In the present study, we investigated the potential changes in the corneal nerve terminals in non–insulin-dependent diabetes mellitus of moderate duration. The dissected corneas were subjected to a protocol of ultracentrifugation to obtain synaptosomes of sensory nerve terminals. Within these nerve varicosities, 2 major mechanisms were examined, viz., alterations of the mechanosensitive channel pannexin1 and ATP release on stimulation of these terminals. We hypothesized that altered cellular location and function of the pannexin channel may contribute to altered mechanosensitivity of the cornea, which in turn may affect wound healing and primary visual function of the cornea. The chief rationale for focusing on examining the pannexin channel is due to its role in mechanosensitivity, as well as its glycosylation property. Pannexin1 remains unchanged between diabetic subjects in comparison to nondiabetic controls. However, lectin immunoassay showed that pannexin1 is significantly more glycosylated in diabetic corneal synaptosomes. Membrane biotinylation assay showed that membrane localization of pannexin1 is significantly enhanced in diabetic samples. Furthermore, S-nitrosylation of the glyco-pannexin1 is significantly decreased in comparison to pannexin1 obtained from corneal varicosities of normoglycemic subjects. The diabetic corneal synaptosomes show enhanced ATP release after potassium chloride stimulation, when compared to controls. Furthermore, we have shown that S-nitrosylation of pannexin1 actually diminishes the ability of pannexin1 to release ATP. Thus, much like the peripheral nerves, the corneal nerves also show increased hypersensitivity in diabetes of chronic duration. All of these pathological changes may cumulatively alter corneal function in diabetes.