Biology subjects

Buffo, A.

Publications and source records attributed to Buffo, A..

7 recordsLinked to original sources

bioRxiv2026

Functional validation of allele-specific LMNB1 silencing in patient-derived astrocytes as a therapeutic option for Autosomal Dominant Leukodystrophy

Adult-onset Autosomal Dominant Leukodystrophy (ADLD) is a rare fatal leukodystrophy caused by increased LMNB1 gene dosage, most commonly resulting from duplication of the LMNB1 locus. Because ADLD is a gene dosage disorder, selective reduction of pathological LMNB1 expression represents a rational therapeutic strategy. Although allele-specific RNA interference has previously been shown to lower LMNB1 levels in patient-derived fibroblasts and directly reprogrammed neurons, its therapeutic effects have not been evaluated in disease-relevant human glial cells or using functional efficacy endpoints. Here, we established human induced pluripotent stem cell-derived astrocytes from ADLD patients as a human glial model in which to validate allele-specific LMNB1 silencing across molecular, cellular, and functional readouts. ADLD astrocytes recapitulated increased LMNB1 expression and characteristic nuclear abnormalities and displayed transcriptional alterations affecting extracellular matrix organization, calcium homeostasis, metabolism and RNA processing. Functionally, these cells also exhibited functional phenotypes suitable for therapeutic evaluation: astrocyte-conditioned medium impaired the viability of both murine and human oligodendroglial cultures, while conditioned-medium and direct astrocyte-seeding paradigms revealed impaired post-lesion myelin recovery in lysolecithin-treated cerebellar organotypic slices. Allele-specific LMNB1 silencing restored physiological LMNB1 levels, corrected nuclear abnormalities, attenuated astrocyte-mediated oligodendroglial toxicity, improved post-lesion myelin recovery, and was associated with selective transcriptional programs associated with extracellular support and cholesterol metabolism. Together, these findings provide molecular, cellular, and functional validation of allele-specific LMNB1 dosage correction in patient-derived human astrocytes and offer key support for LMNB1-lowering strategies in disease-relevant human glial cells.

neuroscience↗

bioRxiv2026

Oligodendroglial deletion of the microcephaly gene Cit-k disrupts cortical connectivity and cognitive function

Neurodevelopmental disorders (NDDs) are increasingly recognized as disorders of brain connectivity and circuit dysfunction. Growing evidence suggests that glial cell and myelin abnormalities may actively contribute to these alterations. Yet, they have been often considered secondary consequences of impaired neuronal development rather than primary drivers of circuit dysfunction. Primary autosomal recessive microcephaly type 17 (MCPH17) is a severe NDD caused by mutations in the CIT gene, encoding Citron kinase (CIT-K). The disease is associated with cognitive and motor deficits, epilepsy susceptibility, and marked hypomyelination in both patients and mouse models, suggesting a contribution of oligodendroglial dysfunction to disease pathophysiology. Here, we investigated the specific role of oligodendroglial Cit-k loss using Sox10Cre;Cit-kfl/fl mice, in which Cit-k is selectively deleted in oligodendrocyte-lineage cells. Mutant mice displayed impaired forebrain myelination at juvenile stages and persistent cortical hypomyelination in adulthood. Despite preserved gross motor function, adult mutants showed deficits in fine motor control, working and recognition memory, and auditory fear memory. These impairments were associated with altered cortico-cortical and cortico-hippocampal functional connectivity. Moreover, consistent with the clinical MCPH17 phenotype, mutant mice exhibited increased susceptibility to kainate-induced seizures. Together, our findings show that oligodendroglial Cit-k loss and the resulting hypomyelination are sufficient to produce long-lasting neurological and behavioral impairments independently of primary neuronal defects. These results identify oligodendrocytes as active contributors to MCPH17 and support a broader role for myelin abnormalities in NDDs. HighlightsO_LICit-k deletion in oligodendroglia disrupts forebrain myelination C_LIO_LICortical hypomyelination persists in adult mutant mice C_LIO_LIMutant mice show deficits in motor control and memory C_LIO_LICortico-cortical and cortico-hippocampal connectivity are altered C_LIO_LIligodendrocytes contribute to microcephaly-associated dysfunctions C_LI

neuroscience↗

bioRxiv2026

Transcranial direct current stimulation (tDCS) promotes myelin repair and plasticity in the mouse motor cortex

Cortical myelin loss and oligodendroglial dysfunction, hallmarks of numerous neurodegenerative and psychiatric disorders, compromise executive, sensory, and cognitive functions by altering circuit activity and integrity. Promoting cortical myelin repair therefore represents a critical therapeutic goal. In this frame, modulation of neuronal activity through non-invasive brain stimulation may represent a promising non-pharmacological approach to support remyelination. To address this issue, we investigated the effects of anodal transcranial direct current stimulation (A-tDCS) in a mouse model of unilateral myelin injury in the motor cortex. A-tDCS was delivered over the contralateral uninjured cortex during a bilateral motor task (locomotion), to enhance the physiological activity of interhemispheric M1-M1 projections and indirectly stimulate the lesioned cortex. When applied during the late phase of demyelination and the onset of repair, A-tDCS accelerated remyelination and increased oligodendroglial survival and maturation in the lesioned cortex, compared with unstimulated controls. Increased myelin was also detected in the directly stimulated uninjured cortex despite unchanged oligodendroglial cell numbers, suggesting de novo myelin formation or remodeling of existing internodes. These structural changes were accompanied by preservation of interhemispheric M1-M1 functional connectivity upon injury. Collectively, our findings demonstrate that A-tDCS promotes cortical myelin repair in vivo, supporting its therapeutic potential for disorders characterized by myelin damage. Notably, the observed effects of tDCS on myelin plasticity in the uninjured cortex - reported here for the first time - reveal a previously unrecognized mechanism underlying tDCS-mediated neuromodulation. HighlightsO_LIAnodal tDCS (A-tDCS) promotes remyelination in the mouse motor cortex (M1) and restores M1-M1 synchrony after demyelinating injury C_LIO_LIA-tDCS enhances oligodendroglial survival and maturation in the injured motor cortex C_LIO_LIA-tDCS induces myelin plasticity in the uninjured cortex C_LI

neuroscience↗

bioRxiv2025

Brain injury reactivates a developmental program driving genesis and integration of transient LGE-class interneurons

Brain lesions can unlock a latent neurogenic potential in parenchymal astrocytes. However, the identity of their neuronal progeny has remained unclear. Here, we show that neurons generated by striatal astrocytes following excitotoxic lesions are transient, yet they reach advanced stages of morphological and functional maturation and integrate into cortico-striatal-thalamic circuits. Single-cell RNA-seq mapping onto an embryonic reference revealed that these cells are not related to adult striatal neuron types but instead belong to the LGE-MEIS2/PAX6 interneuron class. Notch abrogation, which mimics neurogenic activation, drives both cortical and striatal astrocytes toward this same interneuron class, revealing a shared intrinsic commitment. In primates, LGE-MEIS2/PAX6 cells transiently populate the embryonic striatum and cortex, and through spatial transcriptomics, we reveal that in mice these cells are also present and widely distributed throughout the telencephalon during embryonic and postnatal development. Thus, unlike other vertebrates in which adult telencephalic astroglia preserve the potential to generate constitutive region-specific neurons, the homologous cells in mammals converge on the generation of a specific transient neuron class, possibly representing a reservoir for circuit plasticity in adult life.

neuroscience↗

bioRxiv2025

A single-cell transcriptomic atlas maps cerebellar astrocyte diversity and uncovers the transcriptional code underlying their maturation trajectories

Astrocytes are increasingly recognized as key regulators of neural circuit development and function, with mounting evidence revealing substantial heterogeneity within and across brain regions. Yet, the full extent of this diversity and its developmental mechanisms remain poorly understood. To address this, we leveraged the uniqueness of the mouse cerebellum, which hosts well-defined astrocyte types and established progenitor pools. Through complementary multi-modal omic approaches, including single-cell RNA sequencing, spatial transcriptomics, trajectory inference, clonal lineage reconstruction, and gene expression and regulatory network analyses, we systematically dissected the molecular diversity and ontogenesis of cerebellar astrocytes. We identified known types and uncovered new subtypes with functional specialization, inferring their developmental trajectories from multiple embryonic niches and postnatal progenitor sources with fate divergence, convergence, and restriction. We further predicted a hierarchical transcriptional regulator code governing this diversification, operating at multiple levels: distinct regulatory modules i) reflect embryonic regionalization and lineage; ii) determine broad astroglial identity; specify iii) Bergmann versus non-Bergmann fates; and guide iv) astrocyte type and v) subtype acquisition. Our findings map and temporally organize transcriptional programs that capture key determinants of astrocyte fate, integrating them along defined trajectories toward diverse astrocyte identities. This high-resolution framework for cerebellar glial diversification offers a model to be challenged across other brain regions.

neuroscience↗

bioRxiv2025

Acute particulate matter (PM10) exposure selectively triggers behavioral alterations in the presymptomatic Experimental Autoimmune Encephalomyelitis (EAE) mouse model of Multiple Sclerosis

Multiple Sclerosis (MS) is a chronic disease of the Central Nervous System, where neuroinflammation and autoimmune response against myelin lead to functional impairments, cognitive and psychiatric symptoms. Exposure to air pollution - in particular to peaks of particulate matter (PM) - has been associated with an increase of hospital admissions for MS onset and relapses and exacerbated neuroinflammation in MS patients. Here, in the MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) mouse model of MS, we tested the hypothesis that exposure to PM10 might influence the disease course and severity in individuals with a predisposing background. Short-term PM10 exposures - occurring either before immunization or during the pre-symptomatic phase - did not modify disease manifestation in EAE mice, as assessed by clinical and neuropathological analyses. Yet, presymptomatic EAE - but not healthy - mice selectively showed increased disinhibited, risk-taking and novelty-seeking behaviors early after being exposed to PM10. These data show a selective vulnerability of immunologically primed mice toward the effects of PM10, occurring before the emergence of overt motor impairment and presenting as specific behavioral alterations.

neuroscience↗

bioRxiv2024

Dynamic spatiotemporal activation of a pervasive neurogenic competence in striatal astrocytes supports continuous neurogenesis following injury

Adult brain neural stem cells (NSCs) are conventionally regarded as rare cells restricted to two niches: the subventricular zone (SVZ) and the subgranular zone. Parenchymal astrocytes can also contribute to neurogenesis after injury, however the prevalence, distribution, and behaviour of these latent NSCs remained elusive. To tackle these issues, we reconstructed the spatiotemporal pattern of striatal astrocytes neurogenic activation after excitotoxic lesion in mice. Our results indicate that a neurogenic potential is broadly distributed throughout the striatum but is focally activated at the lesion border. In this region, similarly to canonical niches, steady state neurogenesis is ensured by the continuous stochastic activation of local astrocytes. Activated astrocytes quickly return to quiescence, while their progeny locally proliferate for about 10 days following a stochastic behaviour that features an acceleration in differentiation propensity. Notably, striatal astrocytes activation rate matches that of SVZ astrocytes indicating a comparable prevalence of NSC potential.

neuroscience↗