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STUDY DESIGN An experimental laboratory study. OBJECTIVE To investigate the pathogenesis of intervertebral disc degeneration (IDD) in a murine model of type 1 diabetes mellitus (DM), namely non-obese diabetic (NOD) mouse. SUMMARY OF BACKGROUND DATA IDD is a leading contributor of low back pain, which represents one of the most disabling symptoms within the adult population. DM is a chronic metabolic disease currently affecting one in ten adults in the United States. It is associated with an increased risk of developing IDD, but the underlying process remains poorly understood. METHODS Total disc glycosaminoglycan (GAG) content, proteoglycan synthesis, aggrecan fragmentation, glucose transporter (mGLUT1) gene expression and apoptosis were assessed in NOD mice and wild-type euglycemic control mice. Spinal structural and molecular changes were analysed by micro-computed tomography (CT), histological staining (Safranin-O and fast green) and quantitative immunofluorescence (anti-ADAMTS-4 and -5 antibodies). RESULTS Compared to euglycemic controls, NOD mice showed increased disc apoptosis and matrix aggrecan fragmentation. Disc GAG content and histological features of NOD mice did not significantly differ from those of euglycemic littermates. CONCLUSIONS These data demonstrate that DM may contribute to IDD by increasing aggrecan degradation and promoting cell apoptosis, which may represent early indicators of the involvement of DM in the pathogenesis of IDD. LEVEL OF EVIDENCE N/A.