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Phelan, M. M.

Publications and source records attributed to Phelan, M. M..

7 recordsLinked to original sources

Inhibition of glioblastoma cell proliferation and invasion by the choline-kinase inhibitor JAS239 varies with cell type and hypoxia

BackgroundElevated choline kinase alpha (ChoK) is observed in most solid tumours including glioblastomas (GBM), yet until recently, inhibitors of ChoK have demonstrated limited efficacy in GBM models. Given that hypoxia is associated with GBM therapy resistance, we hypothesised that tumour hypoxia could be responsible for such limitations. We therefore evaluated in GBM cells, the effect of hypoxia on the function of JAS239, a potent ChoK inhibitor. MethodsRodent (F98 and 9L) and human (U-87 MG and U-251 MG) GBM cell lines were subjected to 72 hours of hypoxia conditioning and treated with JAS239 for 24 hours. NMR metabolomic measurements and analyses were performed to evaluate the signalling pathways involved. In addition, cell proliferation, cell cycle progression and cell invasion were measured in cell monolayers and 3D spheroids, with or without JAS239 treatment in normoxic or hypoxic cells to assess how hypoxia affects JAS239 function. ResultsHypoxia and JAS239 treatment led to significant changes in the cellular metabolic pathways, specifically the phospholipid and glycolytic pathways associated with a reduction in cell proliferation via induced cell cycle arrest. Interestingly, JAS239 also impaired GBM invasion. However, JAS239 effects were variable depending on the cell line, reflecting the inherent heterogeneity observed in GBMs. ConclusionOur findings indicate that JAS239 and hypoxia can deregulate cellular metabolism, inhibit proliferation and alter cell invasion. These results may be useful for the design of new therapeutic strategies based on ChoK inhibition that can act on multiple pro-tumorigenic features.

cancer biology↗

A review of online learning strategies for biological NMR techniques a survey of educators

Disruption to teaching over the pandemic has led to a range of online and digital solutions. Given the utility of software and remote platforms for NMR teaching a UK-based survey for NMR educators in undergraduate and postgraduate teaching was rolled out Spring 2022 in order to establish what online tools and techniques are employed to teach NMR to biological sciences and appraise their relative efficacy. Based on the survey outcomes an overview of the breadth of methods employed as well as their perceived effectiveness is presented with a list of recommendations for common and successful strategies for online (and hybrid) teaching of NMR to the life sciences.

scientific communication and education↗

Determining predictive metabolomic biomarkers of meniscal injury in dogs with cranial cruciate ligament disease

ObjectivesThe objective of this study was to use for the first time proton nuclear magnetic resonance spectroscopy (1H NMR) to examine the metabolomic profile of stifle joint synovial fluid from dogs with cranial cruciate ligament rupture with and without meniscal injuries. We hypothesised this would identify biomarkers of meniscal injury. MethodsStifle joint synovial fluid was collected from dogs undergoing stifle joint surgery or arthrocentesis for lameness investigations at three veterinary hospitals in the North-West of England. Samples underwent 1H NMR spectroscopy and metabolite identification. We used multivariate and univariate statistical analysis to identify differences in the metabolomic profile between dogs with cranial cruciate ligament rupture and meniscal injury, cranial cruciate ligament rupture without meniscal injury, and neither cranial cruciate ligament rupture nor meniscal injury, taking into consideration specific clinical variables. Results154 samples of canine synovial fluid were included in the study. 64 metabolites were annotated to the 1H NMR spectra. Six spectral regions were found to be significantly altered between groups with cranial cruciate ligament rupture with and without meniscal injury, including three attributed to NMR mobile lipids (mobile lipid -CH3 [p=0.016], mobile lipid -n(CH3)3 [p=0.017], mobile unsaturated lipid [p=0.031]). Clinical SignificanceWe identified an increase in NMR mobile lipids in the synovial fluid of dogs with meniscal injury which are of interest as potential biomarkers of meniscal injury, as well as understanding the metabolic processes that occur with meniscal injury.

molecular biology↗

Replicative ageing perturbs the metabolic signature of murine C2C12 skeletal myotubes

IntroductionChronological ageing is associated with mitochondrial dysfunction and increased reactive oxygen species (ROS) production in skeletal muscle. However, the effects of replicative ageing on skeletal muscle cellular metabolism are not well known. Using an established myoblast model of cellular (replicative) ageing, we investigated the impact of ageing on energy metabolism in murine C2C12 myotubes. MethodsControl (P7-11) and replicatively aged (P48-51) C2C12 myoblasts were differentiated over 72-120 h. Mitochondrial bioenergetics were investigated by respirometry and mitochondrial superoxide and cellular ROS were measured in the absence and presence of antimycin A (AA). Genes related to mitochondrial remodelling and the antioxidant response were quantified by RT-qPCR. Intracellular metabolites were quantified using an untargeted 1H-NMR metabolomics pipeline. ResultsMitochondrial coupling efficiency (Control: 79.5 vs. Aged: 70.3%, P=0.006) and relative oxidative ATP synthesis (Control: 48.6 vs. Aged: 31.7%, P=0.022) were higher in control vs. aged myotubes, but rates of mitochondrial superoxide production were lower (Control: 2.4x10-5 {+/-} 0.4 x 10-5 vs. Aged: 9.7x10-5 {+/-} 1.6x10-5 RFU/sec/cell; P=0.035). Replicatively aged myotubes had greater mRNA expression of mfn2 and Tfam compared to control. Yet, Nrf2 and PGC-1 expression were 2.8-fold and 3.0-fold higher in control versus aged myotubes over 24 h and 48 h (P<0.05), respectively. Branched chain amino acids L-leucine, L-isoleucine and L-valine, and L-carnitine were less abundant in aged versus control myotubes. Conclusion(s)Replicative ageing is associated with bioenergetic uncoupling, increased ROS production and impaired amino acid metabolism. Our findings suggest that cellular mitochondrial dysfunction and altered energy metabolism may exacerbate the age-related decline in skeletal muscle mass and function.

cell biology↗

A robust method for performing 1H-NMR lipidomics in embryonic zebrafish

The embryonic zebrafish is an ideal system for lipid analyses with relevance to many areas of bioscience research, including biomarkers and therapeutics. Research in this area has been hampered by difficulties in extracting, identifying and quantifying lipids. We employed 1H-NMR at 700MHz to profile lipids in developing zebrafish embryos. The optimal method for lipidomics in embryonic zebrafish incorporated rapid lipid extraction using chloroform and an environment without oxygen depletion. Pools of 10 embryos gave the most acceptable signal-to-noise ratio, and the inclusion of chorions in the sample had no significant effect on lipid abundances. Embryos, bisected into cranial (head and yolk sac) and caudal (tail) regions, were compared by principal component analysis and analysis of variance. The lipid spectra (including lipid annotation) are available in the public repository MetaboLights (MTBLS2396).

biochemistry↗

Metabolomic and Proteomic Stratification of Equine Osteoarthritis

Osteoarthritis (OA) is characterised by loss of articular cartilage, synovial membrane dysfunction and subchondral sclerosis. Few studies have used a global approach to stratify equine synovial fluid (SF) molecular profiles according to OA severity. SF was collected from 58 metacarpophalangeal (MCP) and metatarsophalangeal joints of racing Thoroughbred horses (Hong Kong Jockey Club; HKJC) and 83 MCP joints of mixed breed horses from an abattoir and equine hospital (biobank). Joints were histologically and macroscopically assessed for OA severity. For proteomic analysis, native SF and SF loaded onto ProteoMiner equalisation columns, to deplete high abundant proteins, were analysed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and label-free quantification. Validation of selected differentially expressed proteins was undertaken using clinical SF collected during diagnostic investigations. Native SF metabolites were analysed using 1D 1H Nuclear Magnetic Resonance (NMR). 1,834 proteins and 40 metabolites were identified in equine SF. Afamin levels decreased with synovitis severity and four uncharacterised proteins decreased with OA severity. Gelsolin and lipoprotein binding protein decreased with OA severity and apolipoprotein A1 levels increased for mild and moderate OA. Within the biobank, glutamate levels decreased with OA severity and for the HKJC cohort, 2-aminobutyrate, alanine and creatine increased with severity. Proteomic and metabolomic integration was undertaken using linear regression via Lasso penalisation modelling, incorporating 29 variables (R2=0.82) with principal component 2 able to discriminate advanced OA from earlier stages, predominantly driven by H9GZQ9, F6ZR63 and alanine. Combining biobank and HKJC datasets, discriminant analysis of principal components modelling prediction was good for mild OA (90%). This study has stratified equine OA using both metabolomic and proteomic SF profiles and identified a panel of markers of interest which may be applicable to grading OA severity. This is also the first study to undertake computational integration of NMR metabolomic and LC-MS/MS proteomic datasets of any biological system.

molecular biology↗

Ex-Vivo Equine Cartilage Explant Osteoarthritis Model - A Metabolomics and Proteomics Study

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-/IL-1{beta} 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-/IL-1{beta} 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 innovative study has identified differentially abundant metabolites, proteins and extracellular matrix derived neopeptides, providing insightful information on OA pathogenesis, enabling potential translation for clinical markers and possible new therapeutic targets.

cell biology↗