Retinal oxidative stress at the onset of diabetes determined by synchrotron FTIR widefield imaging: towards diabetes pathogenesis.
Retinal oxidative stress at the onset of diabetes determined by synchrotron FTIR widefield imaging: towards diabetes pathogenesis.
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DOI：
10.1039/c6an02603f
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发表时间：
2017-03-27
期刊：
影响因子：
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通讯作者：
Hirschmugl CJ
中科院分区：
文献类型：
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作者：
Aboualizadeh E;Ranji M;Sorenson CM;Sepehr R;Sheibani N;Hirschmugl CJ
糖尿病视网膜病变是糖尿病的一种微血管并发症，可导致失明。在目前的研究中，我们的目标是确定糖尿病引起的、糖尿病发病时神经视网膜中高度局部性的生化变化的性质。采用高分辨率同步傅里叶变换红外光谱(S-FTIR)广域显微镜结合多变量分析技术，在细胞水平上以空间分辨率识别糖尿病视网膜病变的生物标志物。我们比较了6周大的Ins2Akita/+杂合子(Akita/+，N=6；糖尿病模型)雄性小鼠和野生型(对照，N=6)小鼠的视网膜组织。雄性秋田/+小鼠在4周大时患上糖尿病。与糖尿病和光谱分离相关的生物标志物的存在存在显著差异(P<；0.001)。在秋田/+样品和WT样品之间观察到了分别属于核酸(964、1051、1087、1226和1710 cm−1)、蛋白质(1662、1608 cm−1)和脂肪酸(2854、2923、2956和3012 cm−1)的红外光谱。视网膜的不同层，即光感受器视网膜层(PRL)、外网状层(OPL)、内核层(INL)和内网状层(IPL)之间的比较表明，在短期糖尿病中，光感受器层是氧化应激最敏感的层。空间分辨化学图像显示，与WT视网膜相比，糖尿病视网膜组织形态发生了异质性和氧化应激诱导的改变。在这项研究中，首次确定了糖尿病视网膜和特定层的光谱生物标志物和空间生化变化。我们相信，从这些研究中得出的结论将有助于弥合我们对糖尿病视网膜病变的分子和细胞机制的理解上的差距。
Diabetic retinopathy is a microvascular complication of diabetes that can lead to blindness. In the present study, we aimed to determine the nature of diabetes-induced, highly localized biochemical changes in the neuroretina at the onset of diabetes. High-resolution synchrotron Fourier transform infrared (s-FTIR) wide field microscopy coupled with multivariate analysis (PCA-LDA) was employed to identify biomarkers of diabetic retinopathy with spatial resolution at the cellular level. We compared retinal tissue prepared from 6-week-old Ins2Akita/+ heterozygous (Akita/+, N=6; a model of diabetes) male mice compared with the wild-type (control, N=6) mice. Male Akita/+ mice become diabetic at 4-weeks of age. Significant differences (P<0.001) in the presence of biomarkers associated with diabetes and segregation of spectra was achieved. Differentiating IR bands attributed to nucleic acids (964, 1051, 1087, 1226 and 1710 cm−1), proteins (1662, 1608 cm−1) and fatty acids (2854, 2923, 2956 and 3012 cm−1) were observed between the Akita/+ and the WT samples. Comparison between distinctive layers of the retina, namely the photoreceptor retinal layer (PRL), outer plexiform layer (OPL), inner nuclear layer (INL) and inner plexiform layer (IPL) suggested that the photoreceptor layer is the most susceptible layer to the oxidative stress in short-term diabetes. Spatially-resolved chemical images indicated heterogeneities and oxidative-stress induced alterations in the diabetic retina tissue morphology compared with WT retina. In this study, the spectral biomarkers and the spatial biochemical alterations in the diabetic retina and in specific layers were identified for the first time. We believe that the conclusions drawn from these studies will help to bridge the gap in our understanding of the molecular and cellular mechanism that contribute to pathobiology of diabetic retinopathy.