Strobel Klaus, van den Hoff Joerg, Pietzsch Jens
Institute of Radiopharmacy, Research Center Dresden-Rossendorf, Dresden, Germany.
J Lipid Res. 2008 Feb;49(2):473-80. doi: 10.1194/jlr.D700024-JLR200. Epub 2007 Nov 16.
We describe a localized proton magnetic resonance spectroscopy ((1)H-MRS) method for in vivo measurement of lipid composition in very small voxels (1.5 mm x 1.5 mm x 1.5 mm) in adipose tissue in mice. The method uses localized point-resolved spectroscopy to collect (1)H spectra from voxels in intra-abdominal white adipose tissue (WAT) and brown adipose tissue (BAT) deposits. Nonlinear least-squares fits of the spectra in the frequency domain allow for accurate calculation of the relative amount of saturated, monounsaturated, and polyunsaturated fatty acids. All spectral data are corrected for spin-spin relaxation. The data show BAT of NMRI mice to be significantly different from BAT of NMRI nu/nu mice in all aspects except for the fraction of monounsaturated fatty acids (FM); for WAT, only the FM is different. BAT and WAT of NMRI mice differ in the amount of saturated and di-unsaturated fatty acids. This method provides a potential tool for studying lipid metabolism in small animal models of disease during the initiation, progression, and manifestation of obesity-related disorders in vivo. Our results clearly demonstrate that localized (1)H-MRS of adipose tissue in vivo is possible at high spatial resolution with voxel sizes down to 3.4 ml.
我们描述了一种用于体内测量小鼠脂肪组织中非常小体素（1.5毫米×1.5毫米×1.5毫米）脂质组成的局部质子磁共振波谱（（1）H-MRS）方法。该方法使用局部点分辨波谱从腹内白色脂肪组织（WAT）和棕色脂肪组织（BAT）沉积物中的体素收集（1）H谱。频域中谱的非线性最小二乘拟合允许精确计算饱和、单不饱和和多不饱和脂肪酸的相对含量。所有光谱数据都进行了自旋-自旋弛豫校正。数据显示，除单不饱和脂肪酸分数（FM）外，NMRI小鼠的BAT在所有方面与NMRI nu/nu小鼠的BAT有显著差异；对于WAT，只有FM不同。NMRI小鼠的BAT和WAT在饱和和二不饱和脂肪酸含量上有所不同。该方法为在体内肥胖相关疾病的起始、进展和表现过程中研究疾病小动物模型中的脂质代谢提供了一种潜在工具。我们的结果清楚地表明，体内脂肪组织的局部（1）H-MRS在体素大小低至3.4毫升的高空间分辨率下是可行的。
