Magnetic Resonance Spectroscopy Lipids Peak May Serve as a Potential Biomarker for Back Pain in Intervertebral Disc Degeneration: An Integrative Metabolomics and Proteomics Study Investigating the Role of the Lipid Droplets-Interleukin-17 Inflammatory Axis.

OBJECTIVE

To explore and validate clinical magnetic resonance spectroscopy (MRS) biomarkers associated with patient-reported symptoms in intervertebral disc degeneration, and to further elucidate the pathogenic mechanisms linking these symptoms to MRS biomarkers via an integrative multiomics approach.

METHODS

Patients categorized into the predominant lipids peak (pLP) group and the non-pLP group based on MRS spectrum lipids peak. Nucleus pulposus cells underwent lipidomics, proteomics and functional experiments. Outcome measures compared, and Pearson correlation coefficient evaluated relationships between symptoms, interleukin (IL)-17 immune-positive cells, and lipid contents. Multivariate linear analysis was employed to analyze the contributions of various variables to patient-reported symptoms.

RESULTS

The pLP group exhibited significantly higher preoperative visual analogue scale (VAS)-back scores (6.5 vs. 4.7, p<0.01) and Oswestry Disability Index (ODI) scores (63.3% vs. 51.2%, p<0.01) compared to the non-pLP group. The multiomics analysis revealed the pLP group was characterized by lipid droplets accumulation in nucleus pulposus cells, and the activation of interleukin-17 (IL-17) inflammatory pathway. Preoperative VAS-back and ODI scores showed positive correlations with the expressions of IL-17 (r=0.555, p<0.001; r=0.566, p<0.001) and the relative lipid contents (r=0.567, p<0.001; r=0.561, p<0.001). Multivariate linear analysis revealed that percentage of IL-17 positive cells and the relative triglyceride contents were associated with preoperative VAS-back pain (p=0.021, p=0.046).

CONCLUSION

Patients with the MRS pLP spectrum showed reduced quality of life and upregulation of the lipid droplets-IL-17 inflammatory pathway in nucleus pulposus cells. Inflammatory factors contribute significantly to chronic low back pain development and progression, affecting patient-reported symptoms. The MRS lipids peak may serve as a potential biomarker for diagnosing and monitoring low back pain.