Keshari Kayvan R, Lotz Jeffrey C, Kurhanewicz John, Majumdar Sharmila
Department of Radiology, University of California, San Francisco, CA 94107, USA.
Spine (Phila Pa 1976). 2005 Dec 1;30(23):2683-8. doi: 10.1097/01.brs.0000188256.88859.9c.
A quantitative high-resolution magic angle spinning (HR-MAS) NMR study of human lumbar discs was conducted to determine biomarkers of disc degeneration.
To correlate HR-MAS quantification of compounds relevant to human lumbar disc degeneration to conventional methods of disc grading such as Thompson grading and biochemical analysis.
It has been shown that there is poor correlation between MRI and CT morphologic findings, spinal biomechanics, and patient symptoms in degenerative disc disease and low back pain. There is a need for an objective, quantitative measurement of biochemical status, morphology, and function.
A total of 17 cadaveric human lumbar intervertebral discs were harvested from patients ranging from 20 to 85 years of age. Quantitative HR-MAS data were acquired, and proteoglycan and collagen biochemical analyses were conducted on 3-mm biopsy punches taken from the anulus fibrosus and nucleus pulposus of each sample. HR-MAS data were fitted and analyzed for hydroxyproline (3.42 ppm), glycine (3.56 ppm), and the N-acetyl peak (2.04 ppm) associated with proteoglycans in comparison with an internal standard. These concentrations were then compared directly to biochemical analyses and Thompson grade.
HR-MAS data correlated well with Thompson grade (P < 0.001). An increase was seen in the levels of unbound hydroxyproline and glycine in annular tissue, which is directly associated to collagen breakdown. This trend also correlates with the changes of total collagen measured by a collagen biochemical assay. HR-MAS also detected a decrease in concentration of nucleus pulposus proteoglycans with degeneration. This proteoglycan decrease was verified by a standard proteoglycan biochemical assay.
Changes in disc chemical composition can be accurately quantified using quantitative HR-MAS NMR spectroscopy ex vivo. This noninvasive method of qualitatively and quantitatively assessing disc degeneration supports the utility of these biomarkers and underlines the need for developing in vivo magnetic resonance spectroscopic imaging (MRSI) for characterizing intervertebral disc degeneration.
进行了一项关于人类腰椎间盘的定量高分辨率魔角旋转（HR-MAS）核磁共振研究，以确定椎间盘退变的生物标志物。
将与人类腰椎间盘退变相关化合物的HR-MAS定量结果与传统的椎间盘分级方法（如汤普森分级和生化分析）进行关联。
已有研究表明，在椎间盘退变和下腰痛中，MRI与CT形态学表现、脊柱生物力学以及患者症状之间的相关性较差。因此，需要一种客观、定量的方法来测量生化状态、形态和功能。
从20至85岁的患者身上共采集了17个尸体人类腰椎间盘。获取了定量HR-MAS数据，并对每个样本的纤维环和髓核取出的3毫米活检组织进行了蛋白聚糖和胶原蛋白生化分析。将HR-MAS数据与内标相比，对与蛋白聚糖相关的羟脯氨酸（3.42 ppm）、甘氨酸（3.56 ppm）和N-乙酰峰（2.04 ppm）进行拟合和分析。然后将这些浓度直接与生化分析结果和汤普森分级进行比较。
HR-MAS数据与汤普森分级具有良好的相关性（P < 0.001）。在纤维环组织中，未结合的羟脯氨酸和甘氨酸水平有所增加，这与胶原蛋白分解直接相关。这一趋势也与胶原蛋白生化检测所测得的总胶原蛋白变化相关。HR-MAS还检测到髓核蛋白聚糖浓度随退变而降低。这种蛋白聚糖的减少通过标准的蛋白聚糖生化检测得到了验证。
使用定量HR-MAS核磁共振波谱法可以在体外准确量化椎间盘化学成分的变化。这种定性和定量评估椎间盘退变的非侵入性方法支持了这些生物标志物的实用性，并强调了开发用于表征椎间盘退变的体内磁共振波谱成像（MRSI）的必要性。
