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Chabronova, A.

Publications and source records attributed to Chabronova, A..

3 recordsLinked to original sources

A New Approach to Monitoring Protein Transfer via Extracellular Vesicles

Extracellular vesicles (EVs) allow the exchange of protein, lipids and genetic material for communication between cells. We developed a method to track protein exchange between cells via EVs, using stable isotope labelling of amino acids in cell culture (SILAC). We compared EV isolation methods: ultracentrifugation and size exclusion chromatography (SEC) and undertook characterisation through nanoparticle tracking analysis (NTA), then optimised the requirement (0-10%) for foetal calf serum (FCS) and EV application concentration (6.5 million-200 EVs/cell seeded). We employed heavy amino acids L-Arg-HCl and L-Lys-2HCl to label donor cells and subsequent EV proteins. Unlabelled recipient cells were treated for 12 hours with EVs, at various concentrations. Mass spectrometry proteomics was used to assess uptake of heavy labelled EVs into recipient cells. A labelling efficiency of 62% was achieved. There was no relationship between the number of EVs applied to cells and the number of heavy proteins detected in the recipient cells. Pathway analysis indicated an inflammatory effect of applying EVs to cells, but the potential cause of this was unclear. We identified transferred protein cargo from EVs in recipient cells. Further optimisation of this method is still necessary.

molecular biology↗

Multi-omic temporal landscape of plasma and synovial fluid-derived extracellular vesicles using an experimental model of equine osteoarthritis

Extracellular vesicles contribute to osteoarthritis pathogenesis through their release into joint tissues and synovial fluid. Limited studies have profiled extracellular vesicles in osteoarthritic biofluids, such as plasma and synovial fluid. Due to the potential involvement in osteoarthritis pathogenesis, synovial fluid-derived extracellular vesicles have the potential to be direct biomarkers in the causal pathway of disease but also enable understanding of their role in disease progression. Utilizing a temporal model of early osteoarthritis, we defined the changes in matched synovial fluid and plasma-derived extracellular vesicle small non-coding RNA and protein cargo using small RNA sequencing and mass spectrometry proteomics. We explored the data with a multi-omic approach including time series clustering, factor analysis and gene enrichment interrogation. Chondrocyte signalling induced by temporal synovial fluid-derived extracellular vesicles derived from the model were analysed using luciferase-based transcription factor activity assays. Extracellular vesicle protein cargo appears to be more important during osteoarthritis progression than small non-coding RNA cargo. Cluster analysis revealed plasma-extracellular vesicles represented a time-dependant response to osteoarthritis induction, were principally derived from protein cargo and were associated with supramolecular complexes. Clusters for synovial fluid-derived extracellular vesicles were associated with an initial osteoarthritis response and represented immune/inflammatory pathways. Factor analysis revealed that plasma-derived extracellular vesicles correlated with day post induction and were primarily composed of proteins which may modulate lipid metabolism in osteoarthritis. Synovial fluid-derived extracellular vesicles significant factors represented intermediate filament and supramolecular complexes reflecting tissue repair responses to osteoarthritis induction. There was a significant interaction between time and osteoarthritis for cAMP response element, Nuclear factor-kappa B response element, serum response element and serum response factor response element reporters with a trend for osteoarthritis synovial fluid-derived EVs at later time points to have a more pronounced effect. Local and systemic osteoarthritis-associated changes in extracellular vesicle cargo profiles in this in vivo model provided a unique opportunity to understand their role in disease propagation and progression and may represent novel biomarkers to stage osteoarthritis.

molecular biology↗

SnoRNA signatures in cartilage ageing and osteoarthritis

ObjectivesOsteoarthritis (OA) presents as a change in the chondrocyte phenotype and an imbalance between anabolic and catabolic processes. Age affects its onset and progression. Small nucleolar RNAs (SnoRNAs) direct chemical modification of RNA substrates to fine-tune spliceosomal and rRNA function, accommodating changing requirements for splicing and protein synthesis during health and disease. This study was undertaken to examine how changes in snoRNAs expression may have a role in OA. MethodsArticular cartilage from young, old and OA knees was used in a microarray study to identify alterations in snoRNA expression. Changes in expression of snoRNAs in OA-like conditions were studied in chondrocytes using interleukin-1 and OA synovial fluid. SNORD26 and SNORD96A knockdown and overexpression were undertaken using antisense oligonucleotides and overexpression plasmids. ResultsWe identified panels of snoRNAs differentially expressed due to ageing (including SNORD96A, SNORD44) and OA (including SNORD26 and SNORD116) and findings were validated in an independent cohort. In vitro experiments using OA-like conditions affected snoRNA expression. Knockdown or overexpression of SNORD26 or SNORD96A resulted in changes in chondrogenic, hypertrophic, rRNA and osteoarthritis related gene expression. ConclusionWe demonstrate that snoRNA expression changes in cartilage ageing, and OA and in OA-like conditions, and when the expression of these snoRNAs is altered this affects chondrogenic and hypertrophic gene expression. Thus, we propose an additional dimension in the molecular mechanisms underlying cartilage ageing and OA through the dysregulation of snoRNAs.

genomics↗