Center for Translational Medicine Research and Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, Guangdong, China.
Shandong University of Traditional Chinese Medicine, Jinan, 250355, Shandong, China.
J Orthop Surg Res. 2024 Oct 7;19(1):632. doi: 10.1186/s13018-024-05110-2.
During the development of disease-modifying intervertebral disc degeneration (IDD) drugs, the rat model of IDD is frequently used for disease progression assessment. The aim of this study was to describe a magnetic resonance (MRI) scoring system for the assessment of different disc conditions in puncture-induced IDD, allowing standardization and comparison of results obtained by different investigators.
A total of 36 Sprague-Dawley rats were utilized in the present study. The animals were divided into two groups: a sham group and an IDD group caused by puncture. The rats in the IDD group were subsequently divided into six categories based on time frames, with five rats in each category. The sham group was divided into two sub-groups (n = 3) for 28 and 56 days, respectively. T2-weighted images of rats consecutively studied with MRI of the coccygeal discs were classified according to the time course using the corresponding histological data. Additional scoring of the micro-CT was employed to identify the progression of bone destruction of the rat model of IDD.
A comparison of the MRI results between the sham group and the IDD group revealed a significant reduction in NP height, area, T2WI value, and DHI in the latter group (P < 0.05). The micro-CT results demonstrated that following acupuncture, there was a notable decline in the BV, Tb.N, and height of the coccygeal vertebra, while the BS/BV and Tb.Sp exhibited a significant increase (P < 0.05). The histological results were analogous to the MRI results, indicating a progressive exacerbation of IDD and a corresponding increase in NP score (P < 0.05). The results of the MRI were found to be consistent with those of the micro-CT and histological analyses (P < 0.05). The results of the study demonstrate a robust correlation between MRI analysis and histological findings. Live animals are employed for MRI analysis to improve experiment comparability. The reliability of the MRI scoring system ensures assessment of disease progression in live animals, while promoting cost savings and animal welfare by avoiding the sacrifice of animals at different times.
The described scoring paradigm has quantitatively been found to differentiate IDD disease progression in an in vivo rat model. Hence, we suggest employing it to evaluate the rat IDD model and assess the effects of treatments in this model.
在开发治疗性椎间盘退变（IDD）的药物过程中，常使用大鼠模型来评估疾病进展。本研究旨在描述一种磁共振（MRI）评分系统，用于评估穿刺诱导的 IDD 中不同椎间盘状态，从而实现不同研究者之间的结果标准化和比较。
本研究共使用 36 只 Sprague-Dawley 大鼠。动物分为两组：假手术组和穿刺诱导的 IDD 组。IDD 组的大鼠随后根据时间框架分为六组，每组 5 只。假手术组分为 28 天和 56 天两个亚组（n=3）。连续对尾部椎间盘进行 MRI 检查的大鼠 T2 加权图像根据相应的组织学数据按时间进程进行分类。还对微 CT 评分进行了附加评分，以确定 IDD 大鼠模型的骨破坏进展情况。
假手术组和 IDD 组的 MRI 结果比较显示，后者的 NP 高度、面积、T2WI 值和 DHI 显著降低（P<0.05）。微 CT 结果表明，针刺后，尾部椎体的 BV、Tb.N 和高度明显下降，而 BS/BV 和 Tb.Sp 显著增加（P<0.05）。组织学结果与 MRI 结果相似，表明 IDD 逐渐加重，NP 评分相应增加（P<0.05）。MRI 结果与微 CT 和组织学分析结果一致（P<0.05）。研究结果表明 MRI 分析与组织学发现之间存在很强的相关性。对活动物进行 MRI 分析以提高实验可比性。MRI 评分系统的可靠性确保了对活动物疾病进展的评估，同时通过避免在不同时间处死动物来节省成本和提高动物福利。
所描述的评分方案已被证明可在体内大鼠模型中定量区分 IDD 疾病进展。因此，我们建议将其用于评估大鼠 IDD 模型并评估该模型中治疗效果。
