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Biology subjects

Kharaz, Y. A.

Publications and source records attributed to Kharaz, Y. A..

4 recordsLinked to original sources

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↗

Age-related changes in microRNAs expression in cruciate ligaments of wild-stock house mice

AimCruciate ligaments (CLs) of the knee joint are commonly injured following trauma or ageing. MicroRNAs (miRs) are potential therapeutic targets in musculoskeletal disorders. This study aimed to 1) identify if wild-stock house (WSH) mice are an appropriate model to study age-related changes of the knee joint and 2) investigate expression of miRs in ageing murine CLs. MethodsKnee joints were collected from 6 and 24 months old C57BL/6 and WSH mice (Mus musculus domesticus) for histological analysis. RNA extraction and qPCR gene expression were performed on CLs in 6, 12, 24, and 30 month WSH old mice. Expression of miR targets in CLs was determined, followed by analysis of predicted mRNA target genes and Ingenuity Pathway Analysis. ResultsHigher CL and knee OARSI histological scores were found in 24 month old WSH mice compared to 6 and 12 month old C57BL/6 and 6 month old WSH mice (p< 0.05). miR-29a and miR-34a were upregulated in 30 month-old WSH mice in comparison to 6, 12 and 24-month-old WSH mice (p<0.05). Ingenuity Pathway Analysis on miR-29a and 34a targets was associated with inflammation through interleukins, TGF{beta} and Notch genes and p53 signalling. Collagen type I alpha 1 chain (COL1A1) correlated negatively with both miR-29a (r= -0.35) and miR-34a (r= -0.33). ConclusionThe findings of this study support WSH house mice as an accelerated ageing model of the murine knee joint. This study also indicated that miR-29a and 34a may be important regulators of COL1A1 gene expression in murine CLs.

molecular biology↗

Scleraxis is required for the growth of adult tendons in response to mechanical loading

Scleraxis is a basic helix-loop-helix transcription factor that plays a central role in promoting tenocyte proliferation and matrix synthesis during embryonic tendon development. However, the role of scleraxis in the growth and adaptation of adult tendons is not known. We hypothesized that scleraxis is required for tendon growth in response to mechanical loading, and that scleraxis promotes the specification of progenitor cells into tenocytes. We conditionally deleted scleraxis in adult mice using a tamoxifen-inducible Cre-recombinase expressed from the Rosa26 locus (Scx{Delta}), and then induced tendon growth in Scx+ and Scx{Delta} adult mice via plantaris tendon mechanical overload. Compared to the wild type Scx+ group, Scx{Delta} mice demonstrated blunted tendon growth. Transcriptional and proteomic analyses revealed significant reductions in cell proliferation, protein synthesis, and extracellular matrix genes and proteins. Our results indicate that scleraxis is required for mechanically-stimulated adult tendon growth by causing the commitment of CD146+ pericytes into the tenogenic lineage, and by promoting the initial expansion of newly committed tenocytes and the production of extracellular matrix proteins.

cell biology↗

Evaluating Muscle Fiber Contractility and the Transcriptome, Proteome, Metabolome, and Lipidome of the mdx/mTR Mouse Model of Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disease characterized by extensive muscle weakness. Patients with DMD lack a functional dystrophin protein, which transmits force and organizes the cytoskeleton of skeletal muscle. Multiomic studies evaluate combined changes in the transcriptome, proteome, and metabolome, and have been proposed as a way to obtain novel insight about disease processes from preclinical models. We therefore sought to use this approach to study pathological changes in dystrophic muscles. We evaluated hindlimb muscles of male mdx/mTR mice, which lack a functional dystrophin protein and have deficits in satellite cell abundance and proliferative capacity. Wild type (WT) C57BL/6J mice served as controls. Muscle fiber contractility was measured, along with changes in the transcriptome using RNA sequencing, and in the proteome, metabolome, and lipidome using mass spectroscopy. While mdx/mTR mice displayed gross pathological changes and continued cycles of degeneration and regeneration, we found no differences in fiber contractility between strains. However, there were numerous changes in the transcriptome and proteome related to protein balance, contractile elements, extracellular matrix, and metabolism. There was only a 53% agreement in fold change data between the proteome and transcriptome, highlighting the need to study protein abundance along with gene expression measures. Numerous changes in markers of skeletal muscle metabolism were observed, with dystrophic muscles exhibiting elevated glycolytic metabolites. These findings highlight the utility of multiomics in studying muscle disease, and provide additional insight into the pathological changes in dystrophic muscles that might help to guide evidence-based exercise prescription in DMD patients.

physiology↗