Publications by authors named "Helen Sanger"

A metabotropic glutamate receptor coupled to phospholipase D (PLD-mGluR) was discovered in the hippocampus over three decades ago. Its pharmacology and direct linkage to PLD activation are well established and indicate it is a highly atypical glutamate receptor. A receptor with the same pharmacology is present in spindle primary sensory terminals where its blockade can totally abolish, and its activation can double, the normal stretch-evoked firing.

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Background: Early mobilisation in critical care is recommended within clinical guidance; however, mobilisation prevalence across the UK is unknown. The study aimed to determine the proportion of patients mobilised out of bed within 48-72 h, to describe their physiological status, and to compare this to published consensus safety recommendations for out-of-bed activity.

Methods: A UK cross-sectional, multi-centre, observational study of adult critical care mobility practices was conducted.

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Using synaptosomes purified from the brains of two transgenic mouse models overexpressing mutated human tau (TgP301S and Tg4510) and brains of patients with sporadic Alzheimer's disease, we showed that aggregated and hyperphosphorylated tau was both present in purified synaptosomes and released in a calcium- and synaptosome-associated protein of 25 kDa (SNAP25)-dependent manner. In all mouse and human synaptosomal preparations, tau release was inhibited by the selective metabotropic glutamate receptor 2/3 (mGluR2/3) agonist LY379268, an effect prevented by the selective mGlu2/3 antagonist LY341495. LY379268 was also able to block pathologic tau propagation between primary neurons in an in vitro microfluidic cellular model.

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Article Synopsis
  • Researchers aimed to create new selective muscarinic M receptor agonists to treat symptoms of Alzheimer's disease.
  • They developed a unique receptor occupancy assay to optimize drug design while monitoring levels in the brain and plasma.
  • The compound SPP1 was identified as a potent, selective partial agonist, demonstrating effective engagement with M receptors in the brain, providing a new tool for studying M receptor roles in health and disease.
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Article Synopsis
  • The M muscarinic acetylcholine receptor (mAChR) presents a promising target for treating cognitive decline in Alzheimer's, leading to the identification of various ligands like GSK1034702, which shows potential benefits but also significant side effects.
  • GSK1034702 acts in a bitopic manner, meaning it interacts with both the orthosteric and allosteric sites on the M mAChR, which may be responsible for its adverse effects in clinical trials.
  • The findings suggest that safer, more selective "pure" positive allosteric modulators with minimal intrinsic activity are preferable for effective treatment with fewer side effects in clinical settings.
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In the search for improved symptomatic treatment options for neurodegenerative and neuropsychiatric diseases, muscarinic acetylcholine M1 receptors (M1 mAChRs) have received significant attention. Drug development efforts have identified a number of novel ligands, some of which have advanced to the clinic. However, a significant issue for progressing these therapeutics is the lack of robust, translatable, and validated biomarkers.

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Article Synopsis
  • The cholinergic signalling system is a key target for improving arousal, cognition, and attention, particularly in neurodegenerative and neuropsychiatric diseases.
  • The M1 and M4 muscarinic receptors, found in important brain areas like the cortex and hippocampus, have been the focus for drug development, but earlier drugs had side effects due to less selectivity.
  • Recent advances in drug screening and design have led to highly selective compounds for these receptors, with some showing promise for treating Alzheimer's disease and related disorders in early clinical trials.
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The current frontline symptomatic treatment for Alzheimer's disease (AD) is whole-body upregulation of cholinergic transmission via inhibition of acetylcholinesterase. This approach leads to profound dose-related adverse effects. An alternative strategy is to selectively target muscarinic acetylcholine receptors, particularly the M1 muscarinic acetylcholine receptor (M1 mAChR), which was previously shown to have procognitive activity.

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Metabotropic glutamate (mGlu) receptors are of considerable interest owing to their role in modulating glutamate transmission via presynaptic, postsynaptic and glial mechanisms. As part of our ongoing efforts to identify novel ligands for these receptors, we have discovered (1S,2R,3S,4S,5R,6R)-2-amino-3-[(3,4-difluorophenyl)sulfanylmethyl]-4-hydroxy-bicyclo[3.1.

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Muscarinic M1 acetylcholine receptors (M1Rs) are highly expressed in the hippocampus, and their inhibition or ablation disrupts the encoding of spatial memory. It has been hypothesized that the principal mechanism by which M1Rs influence spatial memory is by the regulation of hippocampal synaptic plasticity. Here, we use a combination of recently developed, well characterized, selective M1R agonists and M1R knock-out mice to define the roles of M1Rs in the regulation of hippocampal neuronal and synaptic function.

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As part of our ongoing research to identify novel agents acting at metabotropic glutamate 2 (mGlu2) and 3 (mGlu3) receptors, we have previously reported the identification of the C4α-methyl analog of mGlu2/3 receptor agonist 1 (LY354740). This molecule, 1S,2S,4R,5R,6S-2-amino-4-methylbicyclo[3.1.

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Background And Purpose: Transient receptor potential vanilloid subtype 3 (TRPV3) is implicated in nociception and certain skin conditions. As such, it is an attractive target for pharmaceutical research. Understanding of endogenous TRPV3 function and pharmacology remains elusive as selective compounds and native preparations utilizing higher throughput methodologies are lacking.

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The group II metabotropic glutamate (mGlu) receptors comprised of the mGlu2 and mGlu3 receptor subtypes have gained recognition in recent years as potential targets for psychiatric disorders, including anxiety and schizophrenia. In addition to studies already indicating which subtype mediates the anxiolytic and anti-psychotic effects observed in disease models, studies to help further define the preferred properties of selective group II mGlu receptor ligands will be essential. Comparison of the in vitro properties of these ligands to their in vivo efficacy and tolerance profiles may help provide these additional insights.

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