Sebag J, Nie S, Reiser K, Charles M A, Yu N T
University of Southern California School of Medicine, Los Angeles.
Invest Ophthalmol Vis Sci. 1994 Jun;35(7):2976-80.
Recent studies have demonstrated increased nonenzymatic glycation in vitreous from patients with diabetic retinopathy. The present study reports the use of Raman spectroscopy as a novel approach for investigating these molecular changes in human vitreous and experimental tissues.
Near-infrared laser-excited Fourier-transform (FT) Raman spectroscopy (RS) was performed on vitreous specimens obtained at surgery from seven patients with proliferative diabetic retinopathy and from 10 controls. Measurements were also obtained from samples of control and glycated (in vitro) rat tail tendon collagen and demineralized chick bone collagen.
Spectroscopy of vitreous samples from patients with diabetic retinopathy revealed two prominent peaks at 1604 cm-1 and 3057 cm-1, corresponding to aromatic C = C and C-H stretching vibrations in pi-conjugated and aromatic molecules. The peak at 1604 cm-1 was threefold higher in vitreous from patients with diabetes than from controls. Spectra obtained from experimental tissues provided evidence suggesting that the results obtained in human vitreous may be due to nonenzymatic glycation and not to the lysyl oxidase pathway.
These findings suggest that human vitreous obtained from subjects with diabetes may be distinguished from control vitreous by FT-RS and that the peaks characterizing the diabetic samples are possibly due to nonenzymatic glycation. Raman spectroscopy may provide a useful method to elucidate the molecular events underlying these abnormalities.
近期研究表明，糖尿病视网膜病变患者玻璃体中的非酶糖基化增加。本研究报告了使用拉曼光谱作为一种新方法来研究人类玻璃体和实验组织中的这些分子变化。
对7例增生性糖尿病视网膜病变患者和10例对照者手术时获取的玻璃体标本进行近红外激光激发傅里叶变换（FT）拉曼光谱（RS）检测。还对对照和糖化（体外）大鼠尾腱胶原蛋白以及脱矿鸡骨胶原蛋白样本进行了测量。
糖尿病视网膜病变患者玻璃体样本的光谱显示在1604 cm-1和3057 cm-1处有两个突出峰，分别对应于π共轭和芳香族分子中的芳香族C = C和C - H伸缩振动。糖尿病患者玻璃体中1604 cm-1处的峰比对照组高三倍。从实验组织获得的光谱提供了证据，表明在人类玻璃体中获得的结果可能是由于非酶糖基化而非赖氨酰氧化酶途径。
这些发现表明，通过FT - RS可以将糖尿病患者的人类玻璃体与对照玻璃体区分开来，并且表征糖尿病样本的峰可能是由于非酶糖基化。拉曼光谱可能提供一种有用的方法来阐明这些异常背后的分子事件。
