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Bernabucci, M.

Publications and source records attributed to Bernabucci, M..

3 recordsLinked to original sources

Meclizine and metabotropic glutamate receptor agonists attenuate severe pain and primary sensory neuron Ca2+ activity in chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) affects about 68% of patients undergoing chemotherapy and causes severe neuropathic pain which is debilitating health problem and greatly reduces quality of life. Cisplatin is a commonly used platinum-based chemotherapeutic drug known to cause CIPN, possibly by causing oxidative stress damage to primary sensory neurons. Metabotropic glutamate receptors (mGluRs) are widely hypothesized to be involved in pain processing. Meclizine is an H1 histamine receptor antagonist which is known to have neuroprotective effects including anti-oxidative effect. Here, we used a mouse model of cisplatin-induced CIPN to test agonists of mGluR8 and group II mGluR as well as meclizine as interventions to reduce cisplatin-induced pain. We performed behavioral pain tests and in vivo entire DRG neurons Ca2+ imaging using genetically-encoded Ca2+ indicator, Pirt-GCaMP3 to monitor different drug interventions on a populational ensemble level. CIPN induced increased spontaneous Ca2+ activity in DRG neurons, increased Ca2+ transient amplitudes, and hyperresponses to mechanical, thermal, and chemical stimuli. We found mGluR8 agonist, DCPG, group II mGluR agonist, LY379268, and Histamine1 receptor antagonist, meclizine all significantly attenuated mechanical and thermal pain caused by CIPN. LY379268 and meclizine, but not DCPG, attenuated DRG neuronal Ca2+ activity elevated by CIPN. Furthermore, meclizine attenuated cisplatin-induced weight loss. These results suggest group II mGluR agonist, mGluR8 agonist, and meclizine are excellent candidates to study for mechanisms and new treatment option for CIPN.

neuroscience

A multimodal cell census and atlas of the mammalian primary motor cortex

We report the generation of a multimodal cell census and atlas of the mammalian primary motor cortex (MOp or M1) as the initial product of the BRAIN Initiative Cell Census Network (BICCN). This was achieved by coordinated large-scale analyses of single-cell transcriptomes, chromatin accessibility, DNA methylomes, spatially resolved single-cell transcriptomes, morphological and electrophysiological properties, and cellular resolution input-output mapping, integrated through cross-modal computational analysis. Together, our results advance the collective knowledge and understanding of brain cell type organization: First, our study reveals a unified molecular genetic landscape of cortical cell types that congruently integrates their transcriptome, open chromatin and DNA methylation maps. Second, cross-species analysis achieves a unified taxonomy of transcriptomic types and their hierarchical organization that are conserved from mouse to marmoset and human. Third, cross-modal analysis provides compelling evidence for the epigenomic, transcriptomic, and gene regulatory basis of neuronal phenotypes such as their physiological and anatomical properties, demonstrating the biological validity and genomic underpinning of neuron types and subtypes. Fourth, in situ single-cell transcriptomics provides a spatially-resolved cell type atlas of the motor cortex. Fifth, integrated transcriptomic, epigenomic and anatomical analyses reveal the correspondence between neural circuits and transcriptomic cell types. We further present an extensive genetic toolset for targeting and fate mapping glutamatergic projection neuron types toward linking their developmental trajectory to their circuit function. Together, our results establish a unified and mechanistic framework of neuronal cell type organization that integrates multi-layered molecular genetic and spatial information with multi-faceted phenotypic properties.

neuroscience

Phenotypic variation within and across transcriptomic cell types in mouse motor cortex

Cortical neurons exhibit astounding diversity in gene expression as well as in morphological and electrophysiological properties. Most existing neural taxonomies are based on either transcriptomic or morpho-electric criteria, as it has been technically challenging to study both aspects of neuronal diversity in the same set of cells. Here we used Patch-seq to combine patch-clamp recording, biocytin staining, and single-cell RNA sequencing of over 1300 neurons in adult mouse motor cortex, providing a comprehensive morpho-electric annotation of almost all transcriptomically defined neural cell types. We found that, although broad families of transcriptomic types (Vip, Pvalb, Sst, etc.) had distinct and essentially non-overlapping morpho-electric phenotypes, individual transcriptomic types within the same family were not well-separated in the morpho-electric space. Instead, there was a continuum of variability in morphology and electrophysiology, with neighbouring transcriptomic cell types showing similar morpho-electric features, often without clear boundaries between them. Our results suggest that neural types in the neocortex do not always form discrete entities. Instead, neurons follow a hierarchy consisting of distinct non-overlapping branches at the level of families, but can form continuous and correlated transcriptomic and morpho-electrical landscapes within families.

neuroscience