Publications by authors named "Giuseppe Chiantia"

Glyphosate (Gly) is a broad-spectrum herbicide responsible for the inhibition of the enzyme 5-enolpyruvylshikimate-3-phosphate synthase known to be expressed exclusively in plants and not in animals. For decades Gly has been thought to be ineffective in mammals, including humans, until it was demonstrated that rodents treated with the Gly-based herbicide Roundup showed reduced content of neurotransmitters (e.g.

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Purpose: In this study, it was aimed to determine the dose-dependent effects of hippocampal amyloid beta (Aβ) on frontal EEG activity and to elucidate the possible non-invasive biomarkers by recording spontaneous EEG in free-moving rats.

Material And Methods: Male albino Wistar rats aged 3 months were randomly divided into 4 groups (n ​= ​8 for each group), obtained by intrahippocampal injection of saline or different doses of Aβ i.e.

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Purpose: RPH3A encodes a protein involved in the stabilization of GluN2A subunit of N-methyl-D-aspartate (NMDA)-type glutamate receptors at the cell surface, forming a complex essential for synaptic plasticity and cognition. We investigated the effect of variants in RPH3A in patients with neurodevelopmental disorders.

Methods: By using trio-based exome sequencing, GeneMatcher, and screening of 100,000 Genomes Project data, we identified 6 heterozygous variants in RPH3A.

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Research into the early impacts of Alzheimer's disease (AD) on synapse function is one of the most promising approaches to finding a treatment. In this context, we have recently demonstrated that the Abeta42 peptide, which builds up in the brain during the processing of the amyloid precursor protein (APP), targets the ryanodine receptors (RyRs) of mouse hippocampal neurons and potentiates calcium (Ca) release from the endoplasmic reticulum (ER). The uncontrolled increase in intracellular calcium concentration ([Ca]), leading to the development of Ca dysregulation events and related excitable and synaptic dysfunctions, is a consolidated hallmark of AD onset and possibly other neurodegenerative diseases.

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GTPases of the Rho family are components of signaling pathways linking extracellular signals to the control of cytoskeleton dynamics. Among these, RAC1 plays key roles during brain development, ranging from neuronal migration to neuritogenesis, synaptogenesis, and plasticity. RAC1 activity is positively and negatively controlled by guanine nucleotide exchange factors (GEFs), guanosine nucleotide dissociation inhibitors (GDIs), and GTPase-activating proteins (GAPs), but the specific role of each regulator is poorly known.

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The oligomeric form of the peptide amyloid beta 42 (Abeta42) contributes to the development of synaptic abnormalities and cognitive impairments associated with Alzheimer's disease (AD). To date, there is a gap in knowledge regarding how Abeta42 alters the elementary parameters of GABAergic synaptic function. Here we found that Abeta42 increased the frequency and amplitude of miniature GABAergic currents as well as the amplitude of evoked inhibitory postsynaptic currents.

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We recorded spontaneous extracellular action potentials (eAPs) from rat chromaffin cells (CCs) at 37 °C using microelectrode arrays (MEAs) and compared them with intracellularly recorded APs (iAPs) through conventional patch clamp recordings at 22 °C. We show the existence of two distinct firing modes on MEAs: a ~ 4 Hz irregular continuous firing and a frequent intermittent firing mode where periods of high-intraburst frequency (~ 8 Hz) of ~ 7 s duration are interrupted by silent periods of ~ 12 s. eAPs occurred either as negative- or positive-going signals depending on the contact between cell and microelectrode: either predominantly controlled by junction-membrane ion channels (negative-going) or capacitive/ohmic coupling (positive-going).

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Article Synopsis
  • CDKL5 deficiency disorder (CDD) is a severe neurodevelopmental condition caused by mutations in the CDKL5 gene, leading to symptoms like early-onset seizures, intellectual disabilities, and visual impairments.
  • The study focuses on the role of metabotropic glutamate receptors 5 (mGluR5) in CDD's pathology, indicating that the condition disrupts their function by affecting the binding and localization of the protein Homer1bc, essential for mGluR5 activity.
  • Using positive-allosteric-modulators (PAMs) to stimulate mGluR5 in mouse models corrected synaptic and behavioral deficits, suggesting mGluR5 could be a viable target for developing therapies for
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Cav1.2 L-type calcium channels play key roles in long-term synaptic plasticity, sensory transduction, muscle contraction, and hormone release. De novo mutations in the gene encoding Cav1.

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Key Points: NMDA receptors (NMDARs) are key molecules for controlling neuronal plasticity, learning and memory processes. Their function is impaired during Alzheimer's disease (AD) but the exact consequence on synaptic function is not yet fully identified. An important hallmark of AD onset is represented by the neuronal accumulation of Amyloid Beta42 oligomers (Abeta42) that we have recently shown to be responsible for the increased intracellular Ca concentration through ryanodine receptors (RyRs).

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