NIHRDataInsights/HRCSData huggingface dataset:
Title: Regulation of M-type K+ channel expression in sensory neurones as a novel mechanism contributing to chronic pain states
Funder: Medical Research Council

Abstract: Excitation of damage-sensing (nociceptive) neurons underlies nociceptive sensory transmission which signals the occurrence or threat of body damage. This pathway is crucial for avoiding harm, however, with the nerve injury or inflammation, electrical activity of nociceptors often persists beyond the duration of the stimulus and causes persistent pain. We seek to investigate the physiological and genetic mechanisms underlying this increased excitability of nociceptive neurons (peripheral sensitization). Our preliminary experiments revealed dramatic down-regulation of the gene encoding a subunit of M-type potassium channel (KCNQ2) in dorsal root ganglia (drG) neurons of rats developing a neuropathic pain condition. Our published data show that KCNQ2 expression can be suppressed by the transcription factor REST and as a consequence of the decrease in M channel expression the excitability of in drG neurons is increased. We have shown the relevance of this mechanism in response to inflammatory insult; interestingly, our preliminary data suggest that REST is also up-regulated under neuropathic pain conditions. These findings put forward the hypothesis for a novel mechanism contributing to peripheral sensitization: transcriptional suppression of M channels. We seek to investigate this novel mechanism. The proposal has three specific aims I) To characterise long-term changes in the expression of Kv7 channels in peripheral sensory neurons after nerve injury. We will provide a comprehensive characterization of the changes in the expression of individual M channel subunits in dorsal root ganglia (drG) neurons following the experimentally-induced nerve injury. II) To determine the role of transcriptional repressor REST in the development of chronic pain. We will generate a transgenic mouse line with tamoxifen-inducible knock-out of REST specifically in sensory neurones (RESTloxP/loxP/AdvCreER-T2 mice); we will characterize the effects of REST knockdown in vivo on the development of neuropathic pain. III) To determine the contribution of the suppression of the KCNQ genes by REST to the development of peripheral sensitization. We will determine how the KCNQ-REST interaction contributes to the development of neuropathic pain; this will include an investigation of the contribution of M channel downregulation to the excitability of neuropathic drG neurones and a study on the efficacy of M channel openers in neuropathic injury. To answer these questions we have developed a strategy incorporating genetic, biochemical, electrophysiological and behavioural methods. The results of this proposal will reveal a novel mechanism of peripheral sensitization, provide potential new targets for the pain management industry and generate new transgenic mice available for use in other pain-related research.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING;2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Mechanisms of autophagy regulation by the Fat/Hippo pathway
Funder: Medical Research Council

Abstract: Neurodegenerative diseases represent a significant human, societal and economic burden, and are a research priority in the biomedical sciences. Autophagy, a lysosomal catabolic process that disposes of unhealthy proteins and organelles, is currently considered essential for the development and progression of most neurodegenerative pathologies. Through advanced functional genomic studies in a drosophila model for the neurodegenerative disease Dentatorubral-pallidoluysian atrophy, we have identified the tumour suppressor Fat and the growth control Hippo pathway as essential for neuronal homeostasis via autophagy. We have established that its effect in neuroprotection is not a secondary consequence of proliferation control. Rather, we report that the Fat/Hippo pathway critically affects autophagy and cell size in neurons. We now plan to study the mechanisms through which the Fat/Hippo pathway impacts on autophagy, in developing and adult post-mitotic neurons. In particular we will establish its intersection with the Tor pathway, known to be a key regulator of both autophagy and cell size, and thus a natural candidate for interacting with the Fat/Hippo pathway in this system. Having pioneered the role of the Fat/Hippo pathway in neurodegeneration, we are ideally placed to perform these studies now, in a very supportive world-renown centre of excellence for neuroscience. The proposed research will have an important biomedical impact, as it will establish the action of the Fat/Hippo pathway, an entirely new player in autophagy and neuronal homeostasis that can be potentially involved in several neurodegenerative conditions.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: NEUROLOGICAL
Title: The neurophysiological basis of prolonged negative BOLD signals
Funder: Medical Research Council

Abstract: The changes in cerebral blood flow, volume and oxygenation that accompany increases in neural activity form the basis of non-invasive neuroimaging techniques such as blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) which allow human brain mapping. Understanding the relationship between cerebral hemodynamics and the underlying evoked neural activity is therefore vital for the interpretation of neuroimaging data. With a unique combination of optical, electrophysiological and MR techniques in a rodent model we have previously explored the quantitative relationships between increases in activity and the accompanying hemodynamics and positive fMRI signals. However, increasingly deactivations are inferred from prolonged negative BOLD signal changes with little evidence that negative neuroimaging signals ubiquitously reflect reductions in electrical activity. If correct, studies using negative signals to infer reductions in activity suggest that an inability to deactivate specific brain regions appears to be the hallmark of all major neurological and psychiatric conditions. Our recently established dedicated 7T rodent MRI has afforded the signal to noise ratio required to detect prolonged negative BOLD signals following presentation of somatosensory stimuli. Thus the current proposal seeks to use combinations of our established techniques to characterise negative BOLD responses. Concurrent optical imaging spectroscopy and fMRI will allow examination of spatio-temporal concordance between negative BOLD signals and the underlying hemodynamics and further parameterisation of models linking the magnitude of hemodynamics to actual fMRI signal changes. Combinations of optical imaging and laser Doppler techniques will provide multi-modal data with which to explore relationships between decreases in blood flow, volume and oxygen consumption. Quantitative ?negative? neurovascular coupling will be compared from cortical regions signals immediately adjacent to those exhibiting positive BOLD and with negative BOLD responses in the opposite cortex. This will reveal whether re-distribution of local vascular resources is in part responsible for negative BOLD responses in cortical areas that share a common local vasculature. Ex-vivo histological and anatomical tracing techniques will inform the underlying cortical connectivity required for stimulus evoked decreases in activity. We will also perform a series of experiments in the awake animal preparation to assess the effects of anaesthesia on the evoked responses. Finally concurrent measure of ?negative? hemodynamics response and reductions in electrical activity will be used to make dynamic models to predict the entire time series of the CBF response from the underlying neural activity.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: NEUROLOGICAL
Title: An investigation of the role of brain amyloid in cognition, brain atrophy and Alzheimer s disease in Down s syndrome
Funder: Medical Research Council

Abstract: Adults with Down?s syndrome (DS) are at high risk for developing Alzheimer s disease (AD) early in life. The extra-copy of the Amyloid Precursor Protein gene due to trisomy 21 leads to an increase in beta-amyloid production. It is widely accepted that beta-amyloid plays a central role in the pathogenesis of AD, but the nature of this is not fully understood. The study of AD in DS enables investigation of beta-amyloid and its impact on cerebral atrophy, cognition and dementia thereby informing the development of preventative therapies specifically those targeting cerebral amyloid turnover. A new technique that enables the in vivo measurement of cerebral deposition of beta-amyloid using Pittsburgh Compound-B (11C-PiB) with positron emission tomography (PET) has been extensively used in the study of sporadic AD, but not in DS. We have successfully completed a pilot study that has demonstrated that the technique is feasible and acceptable to people with DS and that beta-amyloid can be detected. We are now proposing a clinical study to measure cerebral beta-amyloid in vivo in adults with DS at different stages (pre-diagnosis and diagnosis stages) of AD. Using cross-sectional and longitudinal designs, dynamic 11C-PiB-PET-MRI scanning, MRI voxel-based measures of regional cerebral morphology, and diffusion tensor MRI to evaluate white matter pathways, our aims are to investigate the relationship between cerebral beta-amyloid distribution and load in people with DS in vivo with the following: ? Regional and generalised cerebral atrophy and white matter pathway integrity; ? Specific cognitive deficits ? Clinical evidence of: a) the pre-dementia state (defined as the ?frontal-like? dementia of DS), and b) AD. In this four-year study we will recruit 60 participants with DS between 35 and 55 years of age with mild to moderate degree of intellectual disability, where 30 will have no evidence of AD, 10 will have clinical evidence of AD and 20 will have symptoms suggestive of a pre-dementia state for AD. All will have full diagnostic and neuropsychological assessments specifically developed to assess dementia in people with intellectual disabilities and the above scans at the beginning of the study. In the second stage, we will re-scan two age-matched groups with DS without dementia divided based on being amyloid positive or negative to investigate cerebral and clinical change over time. Between and within participant analyses will be used to establish the relationship between cerebral amyloid deposition, atrophy, white matter tract integrity and clinical status.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Probing the molecular origins of Parkinsons disease using camel single domain antibodies
Funder: Medical Research Council

Abstract: The aggregation of alpha-synuclein and its deposition into Lewy Bodies are key pathological hallmarks of Parkinson s disease. Despite the importance of these processes, however much remains to be understood about the specific mechanism of aggregation of alpha-synuclein and its relationship to the pathogenesis of Parkinson s disease. Our objective is to address these questions by modulating alpha-synuclein aggregation, both in vitro and in vivo, with conformation-specific antibody fragments. These molecules target different epitopes of the monomeric form of alpha-synuclein and alter the in vitro and in vivo aggregation properties of alpha-synuclein. The binding of each antibody fragment to alpha-synuclein will be characterised at atomic level detail by using a wide range of methods, including NMR spectroscopy, X-ray crystallography and advanced computational techniques. These structural studies will then be combined with biophysical investigations of the effects of each antibody fragment on the kinetics of the alpha-synuclein aggregation pathways, using single molecule fluorescence correlation spectroscopy and transmission electron microscopy. Together, these data will enable an accurate molecular level dissection of the mechanisms underlying the formation of different types of alpha-synuclein aggregates, ranging from oligomers to fibrils. In order to understand the relationship between alpha-synuclein aggregation and neurodegeneration, the effects of each antibody fragment on the in vivo neurotoxicity of alpha-synuclein aggregation will be investigated with in situ and in vivo models of Parkinson s disease with different levels of complexity, from neuronal cell-line models, to C. elegans and D. melanogaster models. Various state-of the art techniques will be used to image alpha-synuclein aggregation and to obtain structural information on the species populated in the cell, such as florescence lifetime imaging (FLIM) and fluorescence recovery after photobleaching (FRAP), which are established in the host laboratory. Analysis of the effecst of each antibody fragment on neurotoxicity combined with the knowledge of how each fragment affects alpha-synuclein in vitro will enable the determination of the key pathogenic steps in the alpha-synuclein aggregation process that underlie the development of Parkinson s disease. We believe that this project has a very high potential to succeed, as it builds on the exceptionally strong expertise of the host laboratory in the study protein aggregation, in particular for alpha-synuclein, and it is most timely, as all key technologies have now been established, either directly or through collaborations.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Novel pathogenic mechanisms implicated in defects of neuromuscular transmission
Funder: Medical Research Council

Abstract: Congenital myasthenic syndromes (CMS) are inherited neuromuscular transmission defects characterised by fluctuating muscle weakness and fatigability, leading to loss of mobility and respiratory failure. A distinct form of CMS, pyridostigmine-responsive limb-girdle CMS, has not previously been associated with any gene defect. Recently, we linked this condition to a locus on chromosome 2p12-15 by genome-wide mapping and identified mutations in the GFAT1 gene as the underlying genetic defect. Subsequently we established that GFAT1 mutations lead to a loss of GFAT1 expression in patient muscle. In contrast to all other CMS genes, GFAT1 is expressed in most tissues. This is the first association of CMS with a non-structural, ubiquitous protein, suggesting novel pathogenic mechanisms leading to NMJ dysfunction. The proposed project aims at understanding how GFAT1 mutations cause an impairment of neuromuscular transmission. The GFAT1 enzyme regulates the flux through the hexosamine biosynthetic pathway which yields the precursor substrates for protein and lipid glycosylation. This includes N- and O- glycosylation of transmembrane and secreted proteins as well as the posttranslational modification by one O-linked beta-N-Acetylglucosamine residue of nucleocytoplasmic proteins (O-GlcNAcylation). In this project we will investigate the consequence of GFAT1 deficiency on these two types of glycosylation for skeletal muscle and NMJ proteins. We will study glycosylation in GFAT1 deficient C2C12 muscle cells, in GFAT1 deficient zebrafish as an animal model and in patient material. Several NMJ transmembrane proteins such as the acetylcholine receptor and the muscle-specific kinase MuSK are glycosylated. We will determine whether GFAT1 deficiency results in a modification of glycosyl residues on these proteins and whether this affects acetylcholine receptor clustering at the NMJ and the NMJ structure in zebrafish. Moreover, O-GlcNAcylation of nuclear and cytoplasmic proteins has been linked to stress response in cells and is thought to have a cytoprotective function. Inability of GFAT1 deficient cells to regulate their stress response might leave them more prone to stress-related damage. We will identify which proteins are O-GlcNAcylated in C2C12 cells, which of these are most affected by GFAT1 deficiency, and how this relates to stress tolerance. Our findings will improve our understanding of posttranslational modifications of the neuromuscular junction. We will determine to what degree disturbed protein glycosylation constitutes a new basic pathogenic mechanism resulting in a synaptic defect.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Cerebral Energy Metabolism in Injured and Uninjured Brain
Funder: Medical Research Council

Abstract: This study aims to investigate derangements in cerebral energy metabolism following traumatic brain injury. While the concept of energy failure is well recognised as a mechanism of neuronal injury and ultimately poor clinical outcome, the specific abnormalities compared with normal metabolism remain unclear. We propose delivering specific 13C labelled substrates to the human brain following trauma using microdialysis, to sequentially interrogate the glycolytic pathway (glucose supplementation), the tricarboxcylic acid cycle (pyruvate supplementation) and oxidative phosphorylation (succinate supplementation). We will monitor the metabolic consequences using a combination of (1) microdialysis parameters (including the lactate/pyruvate ratio to determine the redox state of the cell), (2) high-resolution Nuclear Magnetic Resonance spectroscopy of the microdialysates to analyse the downstream metabolites and determine the positions of 13C-labelling within these molecules (to ascertain which biochemical pathways are functioning), and (3) in vivo 31P Magnetic Resonance Spectroscopy to assess energy status (phosphocreatine/inorganic phosphate ratio and phosphocreatine/adenosine triphosphate ratio) at a cellular level. In order to differentiate the consequences of injury from normal metabolism, we will carry out parallel microdialysis studies in uninjured human brain and muscle. Together, these studies will increase our understanding of metabolic impairment in the injured brain and determine whether supplementation of specific substrates can improve energy generation as a potential therapeutic avenue. This may ultimately lead to novel strategies to improve clinical outcome.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Accelerated Discovery of Molecules and Biological Pathways Perturbed in Mendelian Neurological Diseases
Funder: Medical Research Council

Abstract: Genomic studies of inherited brain malformations and neurodegenerative diseases have provided invaluable insights into molecules and biological pathways involved in human brain development and function. To circumvent limitations imposed by locus heterogeneity and diagnostic misclassifications, these studies have typically involved the investigation of large families with multiple affected individuals. However despite these molecular discoveries comparatively little remains known about the intricate molecular processes that orchestrate brain development, or that underlie neurodegenerative disease, and the identification of further neurological disease genes is desperately required. Recently, avant-garde genetic studies have indicated the potential for whole-exome re-sequencing of smaller families, involving just 2-3 affected cases, to identify novel disease genes. This approach offers great promise for the accelerated discovery of normal and pathological neurobiological processes. The Centre for Community Genomic Studies (CCGS) is a recently formed international consortium for the investigation of inherited diseases which occur amongst consanguineous communities (UK, Oman, Iran, Malaysia, India, and Amish) and the translation of research findings into scientific and community benefit. Through this consortium we have access to substantial numbers of families with forms of inherited neurological disease. By identifying and studying large patient groups of particular diseases which occur at high frequency in these communities we have been able to robustly position novel gene loci responsible for four neurodevelopmental conditions, as well as six forms of neurodegenerative disease. We have also identified large numbers of smaller consanguineous families with at least two or three individuals affected by variable degrees of developmental delay either in isolation, or involving other clinical features. In this proposal we aim to apply new sequencing technologies to discover the genes and mutations responsible for each of the 10 conditions which we have already mapped. In parallel with this we intend to undertake whole exome analysis in 20 smaller families with forms of neurological disease and demonstrate the efficacy of this approach to streamline gene discovery. By applying modern genomic technologies to accelerate the identification of genes responsible for a range of neurological conditions made accessible through the CCGS community genetics programs, this initiative offers considerable potential to increase our knowledgebase of both neurodevelopmental and neurodegenerative pathways.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Application of a human stem cell model of early Alzheimers disease pathology to drug discovery and testing
Funder: Medical Research Council

Abstract: There are currently no disease-modifying drugs in clinical use for Alzheimer?s disease (AD), of which there are 25 million cases worldwide. A human model of AD will be very useful for research and drug development, to complement available animal models. Any relevant disease model must use the cell type affected by the disease, and develop pathology on a useful timescale. To solve both of those problems, we developed a process to differentiate human pluripotent stem cells to cerebral cortex neurons, the part of the brain affected in AD. To model early stage Alzheimer?s disease, we used this process to generate cortical neurons from Down syndrome iPS cells (DS-iPS). Adults with Down syndrome develop early-onset Alzheimer?s disease, primarily due to increased expression of the amyloid precursor protein on chromosome 21. A key step in the development of Alzheimer?s disease in vivo is the increased generation and accumulation of the pathogenic Abeta42 peptide fragment of APP in the cerebral cortex. The generation of Abeta42, the formation of amyloid plaques and neuronal cell death occur in our system over a period of months, compared to typically several decades in vivo. Production of Abeta42 is abolished in this system by known gamma secretase inhibitors, demonstrating the utility of this system for identifying disease-modifying compounds. We propose to use this DS-iPS model of early-onset AD as an in vitro platform for screening and identifying compounds that alter Abeta production and accumulation and Abeta42-mediated cell death, using libraries of known bioactive molecules. This will both demonstrate the utility of systems such as this for disease modelling and drug testing/discovery, but also identify novel candidate disease-modifying compounds.


Research activity codes: 5.1 PHARMACEUTICALS;5.2 CELLULAR AND GENE THERAPIES
Health categories: NEUROLOGICAL