Endplate Lesions of the Lumbar Spine: Biochemistry and Genetics

Endplate lesions of the lumbar spine are often asymptomatic and frequently observed incidentally by radiological assessment. Variants in the vitamin D receptor gene (VDR) and an increase in some biochemical markers related to the osteo-cartilaginous metabolism were found in patients with endplate lesions. The aim of this study was to identify biochemical and genetic markers putatively associated with the presence of endplate lesions of the lumbar spine.

Quantification of circulating bone remodeling proteins was obtained from 10 patients with endplate lesions and compared with age- and sex-matched controls. Whole exome sequencing (WES) was performed on patient genomic DNA using the Novaseq 6000 platform (Illumina, San Diego, CA, USA), obtaining a median read depth of 117×-200×, with ≥98% of regions covering at least 20×. The sequencing product was aligned to the reference genome (GRCh38.p13-hg38) and analyzed with Geneyx software.

We observed modifications in the levels of circulating proteins involved in bone remodeling and angiogenesis. We identified variants of interest in aggrecan (ACAN), bone morphogenetic protein 4 (BMP4), cytochrome P450 family 3 subfamily A member 4 (CYP3A4), GLI family zinc finger 2 (GLI2), heparan sulfate proteoglycan 2 (HSPG2), and mesoderm posterior bHLH transcription factor 2 (MESP2). VDR polymorphism (rs2228570) was present in nine patients, with the homozygotic ones having more severe endplate lesions and higher levels of the analyzed circulating markers in comparison with heterozygotic patients.

These data represent interesting evidence of genetic variants, particularly in VDR, and altered levels of circulating markers of bone remodeling associated with endplate lesions, which should be confirmed in a larger population. The hypothesis suggested by our results is that the endplate lesions could be the consequence of an altered ossification mechanism at the vertebral level.