NIHRDataInsights/HRCSData huggingface dataset:
Title: Neurotoxicity of human serum amyloid P component
Funder: Medical Research Council

Abstract: We have lately demonstrated that exposure to the normal human plasma protein, serum amyloid P component (SAP), in vitro or in vivo, damages cerebral neurones causing major abnormalities of synaptic transmission. The cerebrospinal fluid (CSF) concentration of SAP is about 1/1000 of the plasma value but the SAP content of the brain is always abnormally increased in Alzheimer's disease (AD) by the avid but reversible binding of SAP to amyloid fibrils and neurofibrillary tangles. The local SAP concentration around these focal lesions must be greater than normal. We propose that long term exposure to even modestly increased levels of human SAP, and/or transient or intermittent exposure to higher levels, may contribute to neuronal damage responsible for cognitive loss. We have reported that our novel bis(D-proline) drug, CPHPC, which depletes circulating SAP, also removes all SAP from the CSF in patients with AD. We will now fully characterise the time and dose dependence, and the specificity, of the effects of our unique, GMP grade, 100% pure human SAP on paired pulse ratio, long term potentiation and neuronal viability in organotypic hippocampal slices, and study cellular binding and entry of SAP and its nuclear localisation. We will investigate the time and SAP dose dependence of abnormalities of cerebral synaptic transmission and cognitive function in two different lines of human SAP transgenic mice expressing, respectively, normal human range and five fold higher human SAP concentrations, and will characterise associated neuropathology compared to wild type littermates. Modulation by transgenic human SAP of abnormalities of synaptic transmission, cognition and neuropathology in the TASTPM mouse model of AD will also be studied. Finally we will assess the capacity of depletion of human SAP, produced by treatment with CPHPC, to abrogate any or all of the neurological abnormalities observed in human SAP transgenic mice.


Research activity codes: 5.1 PHARMACEUTICALS;2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Investigating the neuroprotective and neuroregenerative properties of bone marrow stem cell mobilising drugs in Friedreich ataxia.
Funder: Medical Research Council

Abstract: Recent studies have suggested that bone marrow-derived stem cells offer protection to neurons via multiple and diverse actions. Furthermore, stem cell derived factors are able to improve some of the metabolic deficiencies seen in cell models of the progressive neurological condition Friedreich ataxia (FRDA), suggesting that transplantation or mobilisation of stem cells may be a potential therapy. Here we propose an exploration of the mechanisms by which bone marrow stem cell mobilising drugs may provide neuroprotection and influence regeneration in FRDA. We hypothesise that these drugs act via multiple mechanisms, with direct neuroprotective effects and secondary reparative effects through facilitation of neuronal regeneration by both intrinsic neural stem cells and mobilised bone marrow cells. We propose to use a combination of cell culture models and FRDA animal models. We will study direct neuroprotective effects of stem cell mobilising drugs on neuronal cultures and inducible pluripotent stem (iPS) cells derived from patients with FRDA. Differentiation of FRDA iPS cells into a neuronal phenotype will allow an analysis of the effect of these drugs on frataxin and mitochondrial signalling pathways. We will also use mouse models of FRDA and analyse the effects of administration of stem cell mobilising drugs. We will determine whether these drugs influence neuronal pathology and whether this is dependent on stem cell mobilisation. We will establish whether administration of these drugs increases entry of stem cells into the brain and whether these cells integrate with endogenous neurons. Using ex vivo cerebellar slices with electrophysiological and single cell PCR, we will determine whether integration of stem cells with endogenous cerebellar cells alters electrical properties or gene expression within the cerebellum. Understanding these therapeutic mechanisms will potentially allow the development of a novel neuroprotective therapy in patients with FRDA.


Research activity codes: 5.2 CELLULAR AND GENE THERAPIES
Health categories: NEUROLOGICAL
Title: Investigation of glial and neuronal regenerative mechanisms in epilepsy utilising a surgical and post mortem tissue collection
Funder: Medical Research Council

Abstract: The cases selected for inclusion will be appropriate to the question addressed in aims, but mainly comparing groups with similar pathology types, as cortical dysplasia, to control groups. The methodology employs use of human tissues. This includes surgical tissues surplus to diagnosis (banked as formalin fixed, paraffin-embedded tissues (FFPE), paraformaldehyde fixed/frozen samples (PFFS) and frozen tissue samples (FS)) and post mortem tissues (standardised block set from all cortical regions of both hemispheres banked as FFPE blocks with the remaining brain archived). All tissue samples are photographed, orientated and volume measurements taken. Standard clinical data is collected includes MRI, EEG, fMRI, neuropsychometry and follow-up information. Age-matched control tissues (post mortem and surgical tissues) are used. In addition comparison between 'lesional' and adjacent 'non-lesional cortex' in the same case avoids variations in tissues volumes and antigenicity due to differences in processing between cases and acts as an additional, internal control. Immunohistochemistry (IHC) and immunofluorescence (IF) methods will utilise established protocols, state-of-the-art methods including signal enhancement (tyramide signal amplification and catalysed signal amplification) where required, and using multiple layered signals for IF. We will use image analysis quantification methods within areas of interest as pre-defined. This will utilised unbiased field sampling methods, quantification of neuronal densities per area or volume using stereological methods and semi-automated analyses. Co-localisation of staining will be assessed through z stacks on IF microscopy, verified with confocal study. In addition, cell co-expression ratios using multichannel IF will be measured. Other cell measures as size, branching complexity, will be introduced as required. Western blots and in-situ hybridisation will be ccarried out using standard laboratory methods.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Investigation of alpha-synuclein pathogenic mechanisms with human stem cells and neurons
Funder: Medical Research Council

Abstract: Parkinson's disease (PD) is a progressive neurodegenerative disorder with no known cure. A prevailing model of PD progression suggests that the small pre-synaptic protein alpha-Synuclein (aSyn) misfolds and forms aggregates the cause neuronal dysfunction and death. Futhermore, these misfolded aggregates are proposed to travel through the brain in a prion-like manner. The exact mechanism of how aSyn causes neuronal death is not known, but significant evidence suggests it directly compromises mitochondrial function. Neuroprotective compounds that prevent or reduce aSyn toxicity halt or slow the progression of PD. Using iPSC lines from a patient with alpha-synuclein triplication, and hESCs engineered to overexpress aSyn, I propose to establish a robust, semi-automated fluorescence-based system to read-out alpha-synuclein phenotypes.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING;2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: AMPA- and GABA(A) receptor signalling and corticospinal motor neuron excitability in mouse models of ALS
Funder: Medical Research Council

Abstract: We will determine functional characteristics of excitatory and inhibitory influences on identified CSMNs in brain slices prepared from SOD1(G93A) 'ALS' mice at different stages of disease progression. Cells will be retrogradely labelled with FluoroGold or latex beads applied to the cervical spinal cord. We will determine the active and passive electrical properties of the neurons and establish any general alterations in their properties at different stages of the disease. We will then examine the contribution of calcium-permeable AMPARs and their auxiliary proteins (TARPs and CNIHs) to synaptic and extrasynaptic signalling. We will record pharmacologically isolated AMPAR-mediated macroscopic currents and synaptic currents. The contribution of specific proteins will be determined by comparing the kinetics, voltage-dependence, calcium-permeability, conductance and pharmacology of synaptic and extrasynaptic receptors with those of recombinant receptors expressed with specific auxiliary subunits in tsA201 cells. To determine how GABAergic signalling is altered during disease progression, we will quantify the relative contribution to charge transfer of phasic and tonic GABA(A)R activation. We will distinguish between pre- and postsynaptic changes by examining pharmacologically isolated mIPSCs (amplitude and kinetics, and the conductance of the underlying channels). To determine the origin of changes in tonic GABA(A)R-mediated currents will examine the properties of native receptors in outside-out somatic patches and compare these with those of recombinant GABA(A)Rs expressed in tsA201 cells. We will assess the impact of GABA(A)R activation on cell excitability and potential changes in chloride homeostasis in recordings using the gramicidin perforated-patch technique to preserve intracellular chloride. Our research will contribute to the understanding of normal brain function and highlight potential strategies for limiting excitotoxic damage of motor neurons in ALS.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: Dissection of the cellular mechanisms of functional MRI using targeted optogenetics
Funder: Medical Research Council

Abstract: Functional MRI (fMRI) has made a dramatic impact on clinical neurology and basic research but the cellular basis of haemodynamic responses underlying BOLD signals remain elusive. Understanding the origins of BOLD signal is essential to make connections between basic and clinical neuroscience. BOLD signals reflect changes in blood flow, volume and the rate of O2 consumption. They are underpinned by the "functional hyperemia" which couples delivery of oxygenated blood to neuronal activity. The emerging consensus is that the reactive hyperemia is not a compensatory response to depletion of O2 but a feed-forward phenomenon. The link between neuronal activity and brain microcirculation is indirect. Recent evidence strongly implicates astrocytes in neurovascular coupling. However, much of the current knowledge comes from in vitro slice work and the role of astrocytes in neurovascular coupling and generation of BOLD signals remains poorly understood. We propose to use optogenetics to study the cellular mechanisms of fMRI and focus on astrocytes. Optogenetics permits targeted manipulation of the specified cell populations using light sensitive proteins. We were first to apply optogenetics to study astrocytes (Science, 2010, 329, 571-5) and are in an excellent position to study role of astroglia neurovascular coupling and fMRI. Astrocytes and neurones will be made to express various optogenetic tools to enable us to monitor the impact of their selective activation or deactivation on cortical microcirculation and this will be paralleled with fMRI at 9.4T. Signalling molecules essential for neurone-to astrocyte-to blood vessels signalling will be identified using genetic and pharmacological tools. Optogenetic activation of neuronal projections and natural stimuli will be applied in order to reveal how compromised astrocitic signalling changes vascular responses and BOLD signals. Our hypothesis is that astrocytes are fundamentally important for generation of BOLD signals.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING;1.4 METHODOLOGIES AND MEASUREMENTS
Health categories: NEUROLOGICAL
Title: Role of HCN ion channels in neuropathic pain: a combined animal and human study
Funder: Medical Research Council

Abstract: Recent experiments in the applicant lab have identified the ion channel HCN2 as an important initiator of neuropathic pain, which opens up the possibility of developing HCN2-selective blockers as novel analgesics with efficacy in neuropathic pain. Some aspects of this work need to be extended in animal models before this idea can be regarded as proven, as detailed below. We also propose to use a clinically approved non-selective HCN blocker, ivabradine, currently employed to treat stable angina, to investigate whether HCN block can in principle relieve neuropathic pain. The animal studies will address the following: 1) Our previous studies have shown that nociceptor-specific deletion of HCN2 prevents the onset of neuropathic pain. We use an inducible Cre-lox system to test whether deletion reverses established neuropathic pain. 2) In complementary experiments we will investigate pharmacological block of neuropathic pain using established non-selective HCN blockers. Are they able to reverse even long-established neuropathic pain? 3) Is there a therapeutic window which will allow suppression of neuropathic pain without interference with the cardiac rhythm through block of the cardiac isoform, HCN4? 4) Are genetic deletion or pharmacological block of HCN2 effective in animal models of common human neuropathic pain conditions e.g. diabetic neuropathy? Human studies will address the following: 5) Does ivabradine reverse mechanical allodynia in a model of neuropathic pain implemented in healthy human volunteers by application of a capsaicin patch? 6) Does ivabradine reverse neuropathic pain in patients? We do not expect a full effect because the dose will be limited by cardiac side effects caused by HCN4 block, but any effect will provide valuable proof of principle for the development of future HCN2-selective blockers.


Research activity codes: 5.1 PHARMACEUTICALS;5.2 CELLULAR AND GENE THERAPIES
Health categories: NEUROLOGICAL
Title: Template neuronal networks in developing neocortex
Funder: Medical Research Council

Abstract: Functional brain circuitry is generated early in life as experience-dependent plasticity shapes pre-existing template neuronal networks. The characteristics of these template networks inevitably constrain subsequent experience-dependent plasticity, yet very little is known about their structure, synaptic properties or development. In developing neuronal circuits of the neonatal cortex, NMDA receptor (NMDAR)-dependent synaptic and structural plasticity is crucial for experience-dependent circuit maturation. Therefore NMDAR-based synaptic connectivity is likely to underlie template networks that are the basis for experience-dependent plasticity. I previously showed that, early in neonatal life, the recurrent excitatory microcircuit in layer 4 of the barrel cortex becomes functionally connected through experience-dependent addition of AMPA receptors (AMPARs) to NMDAR-containing synapses, resulting in a highly inter-connected circuit. Preliminary data suggests that, before the emergence of AMPAR-based connectivity, there is substantial NMDAR-mediated synaptic connectivity that represents the template network. This proposal aims to define how and when the NMDAR-based neuronal template network emerges and relate its properties to the experience-dependent plasticity that subsequently acts upon it. 2-photon optical stimulation and patch clamp electrophysiology will be used to map NMDAR- and AMPAR-based synaptic connectivity in layer 4 of neonatal barrel cortex slices. Day-by-day analysis of postnatal template network development will provide information on connectivity levels and synaptic properties. Network analysis will measure the relationship between template and functional network architecture. In vivo imaging of neuronal structural dynamics will describe the link between anatomical and synaptic development. Defining the properties of template neuronal networks will reveal the basis of experience-dependent plasticity that underlies healthy brain development.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: NEUROLOGICAL
Title: Developmental Clinical Studies - Optimising STN-DBS stimulation for late-emerging
Funder: Medical Research Council

Abstract: A significant proportion of PD patients develop severe axial problems within 5 years of STN-DBS. The primary objectives of this investigative study are to establish 1) whether these axial symptoms can be alleviated by altering stimulation parameters, 2) whether the optimal parameters are the same for different motor functions for individual patients, and 3) to what extent the optimised settings for each motor function varies across a cohort of patients with emergence of gait and/or balance problems and who have received STN-DBS for 3 years or more. To achieve this we will develop a series of laboratory-based tests to statistically determine for individual patients small changes that may occur in gait, freezing of gait, balance, posture, and upper limb movements. Motor performance will be measured using CODA motion analysis system, which determines the 3D whole body position in space. In an initial study, we will apply these methods to a cohort of 15 non-operated PD patients, studied on and off levodopa, and a group of age-matched healthy control subjects. Patients' clinical state will be rated using UPDRS. These data will establish a spectrum of values for each test and demonstrate they are sufficiently sensitive to reflect clinical state. We then will apply the tests to the cohort of 15 implanted patients with emerging axial symptoms in the following three stages: 1) Varying stimulation frequency from 50 to 150 Hz in 20 Hz steps using voltages with equivalent energy; 2) varying stimulation frequency in 10 Hz steps centred on the two 'best' frequencies from stage 1 tailored for each patient; 3) varying the stimulation voltage using frequencies determined in stages 1 and 2 for each patient. At each stage the patient and experimenter will be blinded to the DBS parameters until the data are measured. These data will provide a detailed picture of the relationship between STN-DBS parameters and motor function and will lead to improvements in PD management.


Research activity codes: 5.5 RADIOTHERAPY AND OTHER NON-INVASIVE THERAPIES;6.5 RADIOTHERAPY AND OTHER NON-INVASIVE THERAPIES
Health categories: NEUROLOGICAL
Title: Coordination of anti-epileptic inhibitory mechanisms in neocortex
Funder: Medical Research Council

Abstract: This project is part of a long-running research agenda to determine what stops focussed bursts of activity spreading out to become full epileptic seizures. Once recruited to an epileptic event, pyramidal cells fire intensely on the crest of large rhythmic depolarizations. Prior to this however, is a period when they experience similarly large depolarizations but do not fire, suggestive of a powerful restraint. This inhibitory veto is a strong candidate for regulating activity at this critical juncture in the evolution of a seizure. How is this inhibitory response to a network crisis coordinated? Undoubtedly synaptic mechanisms are involved, but an underexplored role is also likely played by gap-junctions (GJs). We hypothesize that the exact pattern of intense discharge of INs is determined by the electrotonic structure of the syncytia. We hypothesize also that the likelihood of activity spreading through the syncytial network is modulated by factors such as rising intracellular Ca2+, shifts in K+ balance and altered membrane K+ permeability. These factors will therefore determine the extent of the inhibitory surround effect. We will further explore the complementary role of discharges in syncytia of different interneuronal classes, and how these are coordinated. To test these hypotheses, we will establish: 1. The electrotonic structure of gap-junction coupled, interneuronal syncytia 2. How ionic concentrations and neuromodulators influence syncytial behaviour 3. How syncytial behaviour is altered in transgenic mouse models of myoclonic epilepsy. 4. Whether "signature" electrophysiological features of syncytia activity can be seen in human recordings.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING;2.1 BIOLOGICAL AND ENDOGENOUS FACTORS
Health categories: NEUROLOGICAL
Title: How the brain controls food intake: the emerging role of the brain GLP-1 system in energy balance and autonomic control
Funder: Medical Research Council

Abstract: This proposal aims at characterising the exact physiological role of GLP-1 expressing neurons in the control of energy balance and autonomic functions. We will experimentally silence or activate GLP-1-expressing neuronal populations in vivo by using viral gene transfer. Specific targeting will be achieved by combining a transgenic mouse line that expresses Cre-recombinase selectively in cells that express GLP-1 or glucagon, with viral expression vectors that are only active in cells expressing Cre-recombinase (FLEX-switch technique). The adeno-associated virus (AAV)-based vectors are injected stereotaxically into the brain region containing GLP-1-expressing neurons and 2-5 weeks after the infections the animals will be tested for effects of GLP-1 neuron modulation on food intake, blood glucose control, cardiovascular and circadian activities. AAV vectors produced for this purpose will include those that inactivate or ablate GLP-1 cells permanently (Tetanus toxin light chain; Diphteria toxin A subunit), and those that inactivate GLP-1 cells transiently (Allatostatin receptor; drEADD hM4D) or activate GLP-1 neurons transiently (Channelrhodopsin2, drEADD hM3Dq), when the appropriate agonist is applied (allatostatin, clozapine-N-oxide or light, respectively). Generation of these tools will also greatly facilitate physiological in vivo studies of other specific cell populations in the CNS. Food and water intake will be monitored using metabolic cages, blood glucose control will be evaluated with oral and intraperitoneal glucose tolerances tests, cardiovascular and respiratory activities will be assessed using standard physiological monitoring in anesthetised animals. Our results will further define the physiological role of the GLP-1 neurons and provide crucial data on the usefulness of a GLP-1 based therapy for metabolic disease. They will also address the question whether overactivation of this system leads to emesis as observed with GLP-1 injection.


Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: NEUROLOGICAL