Project description:Short-read NGS technology (SOLIDTM, Life Technologies) was used to establish a comprehensive repertoire of miRNA expressed in either equine cartilage or subchondral bone. Undamaged cartilage and subchondral bone samples from 10-month Anglo-Arabian foals affected by osteochondrosis (OC) were analyzed and compared with samples from healthy foals. Samples were also subjected or not to an experimental mechanical loading to evaluate the role of miRNAs in the regulation of mechano-transduction pathways. Epiphyseal cartilage and subchondral bone miRNome were defined, including about 300 new miRNAs. Differentially expressed miRNAs were identified between bone and cartilage from healthy and OC foals, as well as after the experimental mechanical loading, suggesting that miRNAs play a role in equine OC physiopathology and in the cellular response to biomechanical stress in cartilage and bone.
Project description:Osteoarthritis (OA) is an age-related degenerative musculoskeletal disease characterised by loss of articular cartilage, synovitis, abnormal bone proliferation and subchondral bone sclerosis. Underlying OA pathogenesis is yet to be fully elucidated with no OA specific biomarkers in clinical use. Ex-vivo equine cartilage explants (n=5) were incubated in TNF-α/IL-1β supplemented culture media for 8 days, with media removed and replaced at 2, 5 and 8 days. Acetonitrile metabolite extractions of 8 day cartilage explants and media samples at all time points underwent 1D 1H nuclear magnetic resonance metabolomic analysis with media samples also undergoing mass spectrometry proteomic analysis. Within the cartilage, metabolites glucose and lysine were elevated following TNF-α/IL-1β treatment whilst adenosine, alanine, betaine, creatine, myo-inositol and uridine levels decreased. Within the culture media, four, four and six differentially abundant metabolites and 154, 138 and 72 differentially abundant proteins, with > 2 fold change, were identified for 1-2 day, 3-5 day and 6-8 day time points respectively. Nine potential novel OA neopeptides were elevated in treated media. Our novel study identified metabolites, proteins and extracellular matrix derived neopeptides which provides insightful information on OA pathogenesis, enabling potential translation for clinical markers and possible novel therapeutic targets.
Project description:A tissue survey of gene expression was conducted using microarray-based transcriptional profiling to compare equine articular cartilage to 10 other normal adult horse tissues. The ten comparative tissues were bladder, cerebellum, kidney, liver, lung, lymph node, muscle, placental villous, spleen, and testis. Messenger RNA transcriptome comparisons were conducted between equine articular cartilage and ten other body tissues using a 9413 element equine-specific cDNA microarray and a two-color dye-swap experimental design. After scanning, the median intensities adjusted for background were entire chip Lowess-normalized for each individual slide. Quantile regression was used to estimate the conditional quantile of the M and A log ratios given the observed average log intensity. Briefly, a nonparametric approach was used to reveal the relationship between percentiles of M and A, where M is log2 (R/G) and A is 0.5 log2 (RG) with R representing expression in articular cartilage and G representing expression in the comparative tissue. The quantile regression was fit using a B-spline with 5 fixed nodes. The 1st, 5th, 10th, 20th, 50th, 80th, 90th, 95th, and 99th conditional quantiles were estimated. For each observed gene intensity in a given tissue comparison, the normal quantile was used as the cartilage-specificity in place of the corresponding estimated regression quantile.
Project description:The objective was to study the time-course effects of interleukin-1β (IL-1β) on equine articular cartilage, with the aim to identify genes of relevance for cartilage pathology in osteoarthritis. Changes in gene expression related to inflammation, extracellular matrix, and phenotypic alterations was studied.
Project description:A tissue survey of gene expression was conducted using microarray-based transcriptional profiling to compare equine articular cartilage to 10 other normal adult horse tissues. The ten comparative tissues were bladder, cerebellum, kidney, liver, lung, lymph node, muscle, placental villous, spleen, and testis.
Project description:Osteoarthritis (OA) is an age-related degenerative musculoskeletal disease characterised by loss of articular cartilage, synovitis, abnormal bone proliferation and subchondral bone sclerosis. The underlying pathogenesis of OA is yet to be fully elucidated with no OA specific biomarkers in clinical use. Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) allow identification of the global metabolome and proteome respectively. During this study, ex-vivo equine cartilage explants (n=5) were incubated in TNF-α/IL-1β supplemented culture media for 8 days, with media removed and replaced at 2, 5 and 8 days. Acetonitrile metabolite extractions of 8 day cartilage explants and media samples at all time points underwent 1H NMR metabolic analysis with media samples also undergoing MS proteomic analysis. Within the cartilage, metabolites glucose and lysine were elevated following TNF-α/IL-1β treatment whilst adenosine, alanine, betaine, creatine, myo-inositol and uridine levels decreased. Within the culture media, four, four and six metabolites were identified as being differentially abundant between control and treatment groups for 1-2 day, 3-5 day and 6-8 day time points respectively. Culture media proteomics identified 154, 138 and 72 proteins differentially abundant, with > 2 fold change, between control and treatment groups for 1-2 day, 3-5 day and 6-8 day time points respectively. Nine potential novel OA neopeptides were elevated in treated media. This is the first study to use a multi ‘omics’ approach to simultaneously investigate the metabolomic profile of ex-vivo cartilage and metabolomic/proteomic profiles of culture media using the TNF-α/IL-1β ex-vivo OA cartilage model. This study has identified a panel of metabolites, proteins and extracellular matrix derived neopeptides which are differentially abundant during an early phase of the OA model which may provide further information on underlying disease pathogenesis, allow potential translation for clinical markers and possible novel therapeutic targets.
Project description:Cells from the superficial (AACS), middle (AACM) and deep (AACD) adult articular cartilage zones and the intermediate (II) and outer (OI) interzone layers and the transient embryonic cartilage of the long bone anlagen (EC) at gestational day 40 were separately collected using laser capture microdissection and microarray analysis was performed to confirm appropriate layer selection.
Project description:Full thickness articular cartilage lesions with penetration into the subchondral bone fill with fibrocartilage-like repair tissue. However, the repair tissue has compromised structural and biomechanical properties relative to normal articular cartilage. The objective of this study was to evaluate transcriptome differences between normal articular cartilage and repair tissue. Bilateral one-cm2 full-thickness lesions were made in the articular surface of the distal femurs of four adult horses followed by subchondral microfracture. Four months postoperatively, repair tissue from the lesion site and grossly normal articular cartilage from each stifle were collected. Total RNA was isolated from tissue samples, linearly amplified, and applied to a 9367-probeset equine-specific cDNA microarray. Eight paired comparisons matched by limb and horse were made with a dye-swap experimental design. Comparisons were validated by histological analysis and quantitative real-time polymerase chain reaction (qPCR). Statistical analysis revealed 3,327 (35.2%) differentially expressed probesets. Biomarkers typically associated with normal articular cartilage and fibrocartilage repair tissue corroborate earlier studies. Other changes in gene expression previously unassociated with cartilage repair were also revealed and validated by qPCR. The magnitude of divergence in transcriptional profiles between normal chondrocytes and the cells that populate repair tissue reveal substantial functional differences between these two cell populations. At the four-month postoperative time point, the relative deficiency within repair tissue of transcripts from genes which typically define articular cartilage indicate that while cells occupying the lesion might be of mesenchymal origin, they have not recapitulated differentiation to the chondrogenic phenotype of normal articular chondrocytes.
Project description:Equine cartilage from young and old donors was used for RNA-Seq analysis. The aim of the study was to identify differentially expressed cartilage transcripts in ageing in order to to characterize molecular mechanisms associated with age-related changes in