Project description:Subchondral insufficiency fracture of the knee (SIFK) is a common cause of knee joint pain that mainly afflicts the elderly. Yet its transcriptional profiles of cartilage in SIFK and OA patients are largely unknown. We performed single-cell RNA sequencing (scRNA-seq) on the cartilage of a SIFK patient, then compared with the processed scRNA-seq files of normal and OA cartilage tissues which were acquired from GSE169454. Cartilage samples from SIFK and OA patients were used to confirm some of the transcriptional expression.
Project description:Objective : To study molecular changes in the articular cartilage and subchondral bone of the tibial plateau from mice deficient in frizzled related protein (Frzb) compared to wild-type mice by transcriptome analysis. Methods : Gene-expression analysis of the articular cartilage and subchondral bone of 3 wild-type and 3 Frzb-/- mice was performed by microarray. Pathway analysis of differentially expressed genes between 3 wild-type and 2 Frzb-/- samples was explored with PANTHER, DAVID and GSEA bioinformatics tools. Activation of the WNT pathway was analyzed using western blot. The effects of Frzb gain and loss of function on chondrogenesis and cell proliferation was examined using ATDC5 micromasses and mouse ribcage chondrocytes. Results : Extracellular matrix-associated integrin and cadherin pathways, as well as WNT pathway genes were upregulated in Frzb-/- samples. Several WNT receptors, target genes, and other antagonists were upregulated, but no difference in active β-catenin was found. Analysis of ATDC5 cell micromasses overexpressing FRZB indicated an upregulation of aggrecan and Col2a1, and downregulation of molecules related to damage and repair in cartilage, Col3a1 and Col5a1. Silencing of Frzb resulted in downregulation of aggrecan and Col2a1. Pathways associated with cell cycle were downregulated. Ribcage chondrocytes derived from Frzb-/- mice showed decreased proliferation compared to wild-type cells. Conclusions : Our analysis provides evidence for tight regulation of WNT signaling, shifts in extracellular matrix components and effects on cell proliferation and differentiation in the articular cartilage - subchondral bone unit in Frzb-/- mice. These data further support an important role for FRZB in joint homeostasis and highlight the complex biology of WNT signaling in the joint. Gene-expression analysis of the articular cartilage and subchondral bone of 3 wild-type and 3 Frzb-/- mice was performed by microarray. Pathway analysis of differentially expressed genes between 3 wild-type and 2 Frzb-/- samples was explored with PANTHER, DAVID and GSEA bioinformatics tools.
Project description:To date, all of the prior osteoarthritic microarray studies in human tissue have focused on the overlying articular cartilage, meniscus, or synovium but not the underlying subchondral bone. In our previous study, our group developed a methodology for high quality RNA isolation from site-matched cartilage and bone from human knee joints, which allowed us to perform candidate gene expression analysis on the subchohndral bone (published on Osteoarthritis and Cartilage on Dec/5/2012 (doi: 10.1016/j.joca.2012.11.016). To the best of our knowledge, the current study is the first to successfully perform whole-genome microarray profiling analyses of human osteoarthritic subchondral bone. We believe our comprehensive microarray results can improve the understanding of the pathogenesis of osteoarthritis and could further contribute to the development of new biomarker and therapeutic strategies in osteoarthritis. Following histological assessment of the integrity of overlying cartilage and the severity of bone abnormality by microcomputed tomography, we isolated total RNA from regions of interest from human OA (n=20) and non-OA (n=5) knee lateral and medial tibial plateaus (LT and MT). A whole-genome profiling study was performed on an Agilent microarray platform and analyzed using Agilent GeneSpring GX11.5. Confirmatory quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis was performed on samples from nine OA individuals to confirm differential expression of 85 genes identified by microarray. Ingenuity Pathway Analysis (IPA) was used to investigate canonical pathways and immunohistochemical staining was performed to validate protein expression levels in samples.
Project description:To date, all of the prior osteoarthritic microarray studies in human tissue have focused on the overlying articular cartilage, meniscus, or synovium but not the underlying subchondral bone. In our previous study, our group developed a methodology for high quality RNA isolation from site-matched cartilage and bone from human knee joints, which allowed us to perform candidate gene expression analysis on the subchohndral bone (published on Osteoarthritis and Cartilage on Dec/5/2012 (doi: 10.1016/j.joca.2012.11.016). To the best of our knowledge, the current study is the first to successfully perform whole-genome microarray profiling analyses of human osteoarthritic subchondral bone. We believe our comprehensive microarray results can improve the understanding of the pathogenesis of osteoarthritis and could further contribute to the development of new biomarker and therapeutic strategies in osteoarthritis.
Project description:Forty eight-week-old male SD-rats were randomly divided into four groups: control group (4 weeks), hypothermia group (4 weeks), control group (8 weeks) and hypothermia group (8 weeks). The hypothermia group was fed at 4±2℃, and the normal group was fed at 25±2℃. After 4 weeks and 8 weeks, Micro-CT and saffron solid green staining were performed to observe the conditions of subchondral bone and cartilage. At 4 weeks, rat subchondral bone tissue was cut for second generation high-throughput sequencing, differential gene screening and gene enrichment analysis, and PCR validation.
Project description:The aim of this study was to characterise the genome-wide DNA methylation profile of osteoathritis (OA) chondrocytes from both knee and hip cartilage, providing the first comparison of DNA methylation between OA and non-OA hip cartilage, and between OA hip and OA knee cartilage. The study was performed using the Illumina Infinium HumanMethylation450 BeadChip array. Genome-wide methylation was assesed in chondrocyte DNA extracted from 23 OA hip, 73 OA knee and 21 healthy hip controls (NOF - neck of femure samples). Keywords: Methylation profiling by array
Project description:Large scale RNA-Seq analysis was performed to investigate the transcriptomic response to osteoarthritis in cartilage and investigate potential subgroups of patients. Data were collected from intact knee cartilage (posterior lateral condyle) from at total of 60 patients with osteoarthritis (OA) following total knee replacement and 10 control non-OA patients following amputation.
Project description:Age as the primary rise factor could be play an important role in incidence and development of osteoarthritis. Several studies have confirmed some tissue specific microRNA were associated with development of osteoarthritis. But if age related microRNA or miRNA cluster would be involved in pivotal post-transcriptional gene regulation in osteoarthritis is unclear. In view of this, we have an idea that several age-related miRNAs would be screened from the rat knee cartilage at different development ages by miRNAs Microarray analysis. We used microarrays to detail the global programme of gene expression underlying the rat knee cartilage and identified distinct classes of age-related miRNAs during this process. The rat knee articular cartilage were selected at successive stages of the rat developmental for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain homogeneous populations of cartilage at each developmental stage in order to increase the temporal resolution of expression profiles. To that end, we hand-selected cartilage according to the rat developmental stages, i.e. seven time-points: newborn (T0), childhood (T1), youth(T2), adult (T3), middle-aged (T4) early-stage elderly(T5) and latter-stage elderly(T6). The objective of the study is to identify miRNA profile of knee articular cartilage at different developmental ages in rats. Total RNA were extracted from the knee articular cartilage of Sprague-Dawley rats at postnatal day 0(T0), week1(T1), week 4(T2), mon3(T3), mon 6(T4), mon 12(T5), and mon 18(T6). The microRNA profile in the specimens was detected with the Affymetrix GeneChip® miRNA 3.0 Array.
Project description:Objective : To study molecular changes in the articular cartilage and subchondral bone of the tibial plateau from mice deficient in frizzled related protein (Frzb) compared to wild-type mice by transcriptome analysis. Methods : Gene-expression analysis of the articular cartilage and subchondral bone of 3 wild-type and 3 Frzb-/- mice was performed by microarray. Pathway analysis of differentially expressed genes between 3 wild-type and 2 Frzb-/- samples was explored with PANTHER, DAVID and GSEA bioinformatics tools. Activation of the WNT pathway was analyzed using western blot. The effects of Frzb gain and loss of function on chondrogenesis and cell proliferation was examined using ATDC5 micromasses and mouse ribcage chondrocytes. Results : Extracellular matrix-associated integrin and cadherin pathways, as well as WNT pathway genes were upregulated in Frzb-/- samples. Several WNT receptors, target genes, and other antagonists were upregulated, but no difference in active β-catenin was found. Analysis of ATDC5 cell micromasses overexpressing FRZB indicated an upregulation of aggrecan and Col2a1, and downregulation of molecules related to damage and repair in cartilage, Col3a1 and Col5a1. Silencing of Frzb resulted in downregulation of aggrecan and Col2a1. Pathways associated with cell cycle were downregulated. Ribcage chondrocytes derived from Frzb-/- mice showed decreased proliferation compared to wild-type cells. Conclusions : Our analysis provides evidence for tight regulation of WNT signaling, shifts in extracellular matrix components and effects on cell proliferation and differentiation in the articular cartilage - subchondral bone unit in Frzb-/- mice. These data further support an important role for FRZB in joint homeostasis and highlight the complex biology of WNT signaling in the joint.
Project description:We report differential expression analysis of RNAseq data in joint-related tissues (articular cartilage and subchondral bone) in healthy foals (4 weeks of age or younger) and healthy adult horses. We find that 1115 genes are differentially expressed in cartilage and 3574 in bone between these two groups. Functional annotation suggests that differences primarily lie in genes involved in growth/turnover of tissue and cell signaling.