Project description:Intervertebral disc degeneration (IDD) leads to low back pain and disability globally. The pathophysiology of IDD is not entirely understood. There is increasing evidence that long noncoding RNAs (lncRNAs) play a key regulatory role in a wide range of biological processes. The purpose of this study was to comprehensively lncRNA and mRNA expression profiles of human intervertebral disc (IVD) tissues, specifically nucleus pulpous (NP) tissues, with early and advanced stages of disc degeneration. The overview of lncRNA and mRNA expression profiles in the current study revealed that differentially expressed lncRNAs and mRNAs were identified that have been reported to be relevant to IDD. Importantly, differentially expressed lncRNAs and mRNAs that regulate the major signaling pathways, such as NF-κB, MAPK, and Wnt signaling, that are well known to be responsible for the pathogenesis of IDD.
Project description:Disc Degeneration is a multifactorial disease which cause severe constant chronic pain. The development of disc degeneration could involve both genetic and environmental factors, so it's important to elucidate the difference in gene expression profiles between degenerative and non-degenerative discs from elderly patients and younger patients, respectively. Affymetrix GeneChip Human Genome U133A Array was used to derive gene expression profiles and identified genes that would express at significantly different levels between degenerative and non-degenerative samples. Human intervertebral disc tissues were harvested from elderly and younger patients with degenerative disc disease and adolescent idiopathic scoliosis, respectively, for RNA extraction and hybridization on Affymetrix microarrays. One degenerative sample was compared to one non-degenerative sample in the same microarray run, and comparative analyses were performed in triplicate. Gene whose expression levels varied across the samples with a log ratio >0.5 or <-0.5 were selected as the genes related to disc degeneration.
Project description:Failure of intervertebral disc components, e.g. the nucleus pulposus causes intervertebral disc disease and associated low-back pain. Despite the high prevalence of disc disease, the changes in intervertebral disc cells and their regenerative potential with ageing and degeneration are not fully elucidated. Understanding the cell lineage, cell differentiation and maintenance of nucleus pulposus may have therapeutic application for the regeneration of degenerative disc, with significant impact for healthy ageing. Here we found that TAGLN expressing cells are present in human healthy nucleus pulposus, but diminish in degenerative disc. By lineage analyses in mice, we found cells in the nucleus pulposus are derived from a peripherally located population of notochord-derived Tagln expressing cells (PeriNP cells). The PeriNP cells are proliferative and can differentiate into the inner part of the nucleus pulposus. The Tagln+ cells and descendants diminish during aging and puncture induced disc degeneration. The maintenance and differentiation of PeriNP cells is partially regulated by Smad4 dependent signaling. Removal of Smad4 by nucleus pulposus specific Cre (Foxa2mNE-Cre), results in decreased Tagln+ cells and abnormal disc morphology, leading to disc degeneration. Our findings propose that the PeriNP Tagln expressing cells are a pool of notochord-derived progenitors that are important for maintenance of the nucleus pulposus and provide insights for regenerative therapy against intervertebral disc degeneration.
Project description:The pathophysiology of intervertebral disc (IVD) degeneration is not entirely understood; however, environmental and endogenous factors under genetic predisposition are considered to initiate the degenerative changes of human IVDs. Aberrant epigenetic alterations play a pivotal role in several diseases, including osteoarthritis. However, epigenetic alternations, including DNA methylation, in IVD degeneration have not been evaluated. The purpose of this study was to comprehensively compare the genome-wide DNA methylation profiles of human IVD tissues, specifically nucleus pulpous (NP) tissues, with early and advanced stages of disc degeneration. We conducted, for the first time, a genome-wide DNA methylation profile comparative study and observed significant differences in DNA methylation profiles between early and advanced stages of human IVD degeneration. The overview of the DNA methylation profile in the current study revealed that differentially methylated loci were identified in many genes associated with known molecules that have been reported to be relevant to IVD degeneration. Importantly, changes in DNA methylation profiles were also found in genes that regulate the major signaling pathways, such as NF-κB, MAPK, and Wnt signaling, that are well known to be responsible for the pathogenesis of human disc degeneration.
Project description:Our studies show that TonEBP-deficiency causes pronounced degeneration of all three intervertebral disc compartments with greater incidence of herniation in the mouse. The disc phenotype is marked by extracellular matrix remodeling, actin cytoskeleton rearrangements, and suppressed proinflammatory gene expression, advancing our understanding of the contributions of TonEBP in intervertebral disc homeostasis and disease. We used microarray to explore the transcriptomics of differentially expressed genes of annulus fibrosus (AF) and nucleus pulposus (NP) tissue in TonEBP haploinsufficient mice on a C57BL/6 background.
