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Kilcoyne, M.

Publications and source records attributed to Kilcoyne, M..

4 recordsLinked to original sources

Structural Analysis of Prostate Cancer N-Glycans Using Graph-Based Structural Metrics

The N-linked glycans are structurally complex carbohydrate modifications that regulate protein folding, immune recognition, and cellular signaling, and their expression is extensively remodeled during cancer progression, making them promising biomarkers. In this study, prostate cancer-associated N-glycans from a range of relevant peer-reviewed studies were curated and digitized to develop a versatile computational framework that quantitatively encodes their spatial complexity across diverse biological systems. We invented two indices--the Distance & Connectivity Index (DCI) and the Position & Composition Index (PCI)--to capture the spatial information in N-glycans as layered architectures, enabling calculation of residue-level path lengths, branching structure, and compositional diversity. DCI summarizes glycan structure as both a scalar and matrix representation, while PCI does the same but also captures monosaccharide diversity, linkage heterogeneity, and cross-layer branching features. These metrics were computed with GlycoAssessor, an open-source platform that extracts information for the DCI and PCI from glycans drawn via Symbol Nomenclature for Glycans (SNFG) notation. Principal Component Analysis (PCA) was applied to evaluate whether glycans from prostate cancer tissues cluster distinctly in a disease-relevant manner. Results show that the spatial information in N-glycans: (1) increased in a multi-dimensional, non-linear manner, (2) objectively segregated structural themes, (3) could function as a potential prostate cancer biomarker that is distinct from mass-to-charge ratio and relative abundance, and (4) could objectively quantify novel subtype classifications of glycans associated with disease states and progression.

bioinformatics↗

Micromotion derived fluid shear stress mediates peri-electrode gliosis through mechanosensitive ion channels

Clinical applications for neural implant technologies are steadily advancing. Yet, despite clinical successes, neuroelectrode-based therapies require invasive neurosurgery and can subject local soft-tissues to micro-motion induced mechanical shear, leading to the development of peri-implant scaring. This reactive glial tissue creates a physical barrier to electrical signal propagation, leading to loss of device function. Although peri-electrode gliosis is a well described contributor to neuroelectrode failure, the mechanistic basis behind the initiation and progression of glial scarring remains poorly understood. Here, we develop an in silico model of electrode-induced shear stress to evaluate the evolution of the peri-electrode fluid-filled void, encompassing a solid and viscoelastic liquid/solid interface. This model was subsequently used to inform an in vitro parallel-plate flow model of micromotion mediated peri-electrode fluid shear stress. Ventral mesencephalic E14 rat embryonic in vitro cultures exposed to physiologically relevant fluid shear exhibited upregulation of gliosis-associated proteins and the overexpression of two mechanosensitive ion channel receptors, PIEZO1 and TRPA1, confirmed in vivo in a neural probe induced rat glial scar model. Finally, it was shown in vitro that chemical inhibition/activation of PIEZO1 could exacerbate or attenuate astrocyte reactivity as induced by fluid shear stress and that this was mitochondrial dependant. Together, our results suggests that mechanosensitive ion channels play a major role in the development of the neuroelectrode micromotion induced glial scar and that the modulation of PIEZO1 and TRPA1 through chemical agonist/antagonist may promote chronic electrode stability in vivo. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=144 SRC="FIGDIR/small/523766v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@962f03org.highwire.dtl.DTLVardef@1e8a6adorg.highwire.dtl.DTLVardef@116cbb6org.highwire.dtl.DTLVardef@19830da_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIPeri-electrode void progression is mediated by fluid flow shear stress C_LIO_LIOscillatory fluid flow shear stress replicates neuroelectrode glial scarring in vitro C_LIO_LIAstrocyte PIEZO1 and TRPA1 are upregulated at the peri-electrode region in response to electrode micromotion C_LIO_LIPIEZO1 pharmaceutical activation diminishes shear stress-induced gliosis C_LIO_LIPIEZO1 chemical inhibition exacerbates gliosis and reduces mitochondrial functions C_LI

neuroscience↗

An insight into new glycotherapeutic in glial inflammation: Understanding the role of glycosylation from acute to chronic phase of inflammation

Glycosylation plays a critical role during inflammation and glial scar formation upon spinal cord injury (SCI) disease progression. Astrocytes and microglia are involved in this cascade to modulate the inflammation and tissue remodelling from acute to chronic phases. Therefore, understating the glycan changes in these glial cells is paramount. Herein a lectin microarray was undertaken using a cytokine-driven inflammatory MGC model, revealing considerable differential glycosylation from the acute to the chronic phase in a cytokine-combination generated inflamed MGC model. It was found that several N- and O-linked glycans associated with glia during SCI were differentially regulated. Pearsons correlation hierarchical clustering showed that groups were separated into several clusters, illustrating the heterogenicity among the control, cytokine combination, and LPS treated groups and the day on which treatment was given. Control and LPS treatments were observed to be in dense clusters. This was further confirmed with lectin immunostaining in which GalNAc, GlcNAc, mannose, fucose and sialic acid-binding residues were detected in astrocytes and microglia. However, this modification (upregulation of sialic acid expression) was inhibited by the sialyltransferase inhibitor which indeed modulates the mitochondrial functions. The present study is the first functional investigation of glycosylation modulation in a MGC (MGC) model which elucidates the role of the glycome in neuroinflammation and identified potential therapeutic targets for future glycol-therapeutics in neuroinflammation

neuroscience↗

Analysis of the Neurotropic and Anti-inflammatory Effects of Neuroelectrode Functionalization with a Heparan Sulphate Mimetic

Further in the search for biomimicry of the properties analogous to neural tissues, and with an ultimate goal of mitigating electrode deterioration via reactive host cell response and glial scar formation, the bio-functionalisation of PEDOT:PTS neural coating is here presented using a heparan mimetic termed (HM) F6. A sulphated mimetic polyanion, with a potential role in neuromodulation in neurodegenerative diseases, and used here for the first time as neural coating. This work acts as a first step towards the use of HM biological dopants, to enhance neuroelectrode functionality, to promote neural outgrowth and to maintain minimal glial scar formation in vitro at the neural-interface. Further, this study opens new possibilities for the evaluation of glycan mimetics in neuroelectrode functionalisation.

bioengineering↗