Comparative metabolomic analysis of human cancellous bone reveals the critical role of linoleic acid metabolism in femur head necrosis based on GC-MS

Abstract

Introduction Femur head necrosis (FHN) is a challengeable clinical disease with unclear underlying mechanism and a low rate of early diagnosis. Objectives To elucidate altered metabolism pathways in FHN and identify putative biomarkers for the detection of FHN. Methods we recruited 26 patients with femur head necrosis and 22 patients with femur neck fracture in this study. Cancellous bone tissues from the femoral heads were collected after the surgery and were analyzed using an untargeted metabolomics approach on the basis of gas chromatography-mass spectrometry (GC-MS). Results The resulting data were analyzed via uni- and multivariate statistical approaches, and we identified 38 metabolites distinctly changed in FHN group. Among them, 33 metabolites were upregulated and 5 were downregulated in FHN. The pathway analysis results showed that linoleic acid metabolism were the most relevant to FHN pathology. On the basis of metabolites network, L-lysine, L-glutamine and L-serine were deemed as the junctions of the whole metabolites. At last, we figured out that 9,12-octadecadienoic acid, inosine, L-proline and octadecanoic acid can be considered as the potential biomarkers of FHN. Conclusion Our study provided a new insight into the pathogenesis of FHN and identified 4 biomarkers in FHN. Linoleic acid metabolism could be considered as the core in FHN and 9,12-Octadecadienoic acid could be considered as the diagnostic marker.