The adipose tissue presents structural and functional changes in obesity and type 1 diabetes (T1DM). In obesity, the size and number of adipocytes and the adipokines' secretion increase. In T1DM, a loss of adipose tissue suggests changes in the metabolic activity of this tissue. A significant challenge is to find alternative non-invasive methods to evaluate molecular changes in adipose tissue related to obesity and T1DM. Recently, Raman spectroscopy and chemometrics techniques have emerged as an alternative tool for biological tissue analysis. In this work, we propose the use of Raman spectroscopy to characterize spectral differences in adipose tissue from different rat groups (control, obese, and T1DM). The Raman spectra were analyzed using direct band analysis, ratiometric analysis, and chemometrics (principal component analysis and support vector machines). We found that the Raman spectra of obese rats showed significant spectral differences compared to control and diabetic groups related to fatty acids Raman bands. Also, the obese group has a significant decrease in the degree of unsaturation of lipids. The PCA-SVM model showed classification performance ranging from 71.43% to 71.79% accuracy for brown and white adipose tissue samples, respectively. In conclusion, the results show that Raman spectroscopy can be used as a non-destructive method to assess adipose tissue according to a metabolic condition.

中文翻译：

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EXPRESS：拉曼光谱在肥胖和 1 型糖尿病大鼠模型中用于脂肪组织评估

脂肪组织呈现肥胖和 1 型糖尿病 (T1DM) 的结构和功能变化。在肥胖症中，脂肪细胞的大小和数量以及脂肪因子的分泌增加。在 T1DM 中，脂肪组织的损失表明该组织的代谢活动发生了变化。一个重大挑战是寻找替代的非侵入性方法来评估与肥胖和 T1DM 相关的脂肪组织中的分子变化。最近，拉曼光谱和化学计量学技术已成为生物组织分析的替代工具。在这项工作中，我们建议使用拉曼光谱来表征来自不同大鼠组（对照、肥胖和 T1DM）的脂肪组织的光谱差异。拉曼光谱使用直接谱带分析、比率分析、和化学计量学（主成分分析和支持向量机）。我们发现，与脂肪酸拉曼谱带相关的对照组和糖尿病组相比，肥胖大鼠的拉曼光谱显示出显着的光谱差异。此外，肥胖组的脂质不饱和度显着降低。PCA-SVM 模型对棕色和白色脂肪组织样本的分类精度分别为 71.43% 到 71.79%。总之，结果表明，拉曼光谱可作为一种非破坏性方法，根据代谢状况评估脂肪组织。肥胖组血脂不饱和度明显下降。PCA-SVM 模型对棕色和白色脂肪组织样本的分类精度分别为 71.43% 到 71.79%。总之，结果表明，拉曼光谱可作为一种非破坏性方法，根据代谢状况评估脂肪组织。肥胖组血脂不饱和度明显下降。PCA-SVM 模型对棕色和白色脂肪组织样本的分类精度分别为 71.43% 到 71.79%。总之，结果表明，拉曼光谱可作为一种非破坏性方法，根据代谢状况评估脂肪组织。