Abstract
BackgroundDegeneration of intervertebral disc is a major cause of lower back pain and neck pain. Studies have tried to unveil the regulatory network using either transcriptomic or proteomic analysis. However, neither have fully elucidated the exact mechanism of degeneration process. Since post-transcriptional regulation may affect gene expression by modulating the translational process of mRNA to protein product, a combined transcriptomic and proteomic study may provide more insight into the key regulatory network of Intervertebral disc degeneration.MethodsIn order to obtain the proteomic and transcriptomic data, we performed label-free proteome analysis on freshly isolated nucleus pulposus cells and obtained transcriptome profiling data from the Gene Expression Omnibus repository. To identify the key regulatory network of intervertebral disc degeneration in nucleus pulposus cells, we performed bioinformatic analyses and established a protein-RNA interacting network. To validate the candidate genes, we performed in vitro experimentation and immunochemistry labeling to identify their potential function during nucleus pulposus degeneration.ResultsThe label-free proteome analysis identified altogether 656 proteins, and 503 of which were differentially expressed between nucleus pulposus cells from degenerated or normal disc cells. Using the existing nucleus pulposus transcriptomic profiling data, we integrated the proteomic and transcriptomic data of nucleus pulposus cells, and established a protein-RNA interacting network to show the combined regulatory network of intervertebral disc degeneration. In the network, we found 9 genes showed significant changes, and 6 of which (CHI3L1, KRT19, COL6A2, DPT, TNFAIP6 and COL11A2) showed concordant changes in both protein and mRNA level. Further functional analysis showed these candidates can significantly affect the degeneration of the nucleus pulposus cell when altering their expression.ConclusionsThis study is the first to use combined analysis of proteomic and transcriptomic profiling data to identify novel regulatory network of nucleus pulposus cells in intervertebral disc degeneration. Our established protein-RNA interacting network demonstrated novel regulatory mechanisms and key genes that may play vital roles in the pathogenesis of intervertebral disc degeneration.
Highlights
Degeneration of intervertebral disc is a major cause of lower back pain and neck pain
Three normal nucleus pulposus (NP) (Pfirrmann grade I, n = 3, age 45 to 49 years, mean age 47 years) and three intervertebral disc degeneration (IDD) NP (Pfirrmann grade IV–V, n = 3, age 46 to 50 years, mean age 48 years) tissue samples were collected from male patients of similar ages, The NP cells were initially isolated to exclude further influences of protein degradation, and cells were extracted for proteomic profiling
We identified 656 proteins, and 503 of which were identified as differentially expressed proteins (> 2 Fold change in expression with P value < 0.05, Additional file 2, Fig. 1a, b), Here we compared the proteome data with transcriptome data using the existing Gene Expression Omnibus (GEO) dataset GSE70362
Summary
Degeneration of intervertebral disc is a major cause of lower back pain and neck pain. Since post-transcriptional regulation may affect gene expression by modulating the translational process of mRNA to protein product, a combined transcriptomic and proteomic study may provide more insight into the key regulatory network of Intervertebral disc degeneration. IDD is initiated by a series of pathogenic processes including biological, biochemical and structural impairment that eventually causes imbalanced metabolism of the extracellular matrix (ECM) of the intervertebral disc, manifesting as collapsed disc and incapability of maintaining movement. Hindered by the poor understanding of its molecular mechanism, no effective non-surgical treatment has been developed to treat IDD. A better understanding of the pathophysiology and mechanism of IDD will provide fundamental basis on developing novel non-surgical treatments to prevent or cure degenerated NP cells from patients with IDD, and to increase the quality of life
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
