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Huttner, A.

Publications and source records attributed to Huttner, A..

5 recordsLinked to original sources

Human-specific features of the cerebellum and ZP2-regulated synapse development

Understanding the unique features of the human brain compared to non-human primates has long intrigued humankind. The cerebellum refines motor coordination and cognitive functions, contributing to the evolutionary development of human adaptability and dexterity. To identify shared and divergent features across primates, we conducted single-nucleus transcriptomic and chromatin accessibility profiling of the adult cerebellar cortex in humans, chimpanzees, macaques, and marmosets. We revealed human-specific transcriptomic and regulatory features, particularly those involved in synaptogenesis. Notably, we identified an enrichment of the sperm receptor zona pellucida glycoprotein 2 (ZP2) and its potential interactors, known for their roles in gamete interaction, in human granule cells. Experimental data show that ZP2 expression in human granule cells is induced by pontine mossy fibers, reducing synaptic proteins at pontocerebellar glomerular synapses, and decreasing cerebellar neuron electrophysiological activity. This unexpected co-option of ZP2 in human-specific synapse regulation provides insights into the evolutionary specialization of the human cerebellum.

neuroscience↗

Chromosomal Aneuploidy in Normal, Non-Neuronal Brain Nuclei of Glioblastoma Patients is Not a Cancer Driver

Aneuploidy is a hallmark of cancers, including high-grade glioma (GBM), one of the most aggressive brain tumors. To assess whether increased aneuploidy already occurs in normal brain tissue of GBM patients, we performed single-nucleus whole-genome sequencing on 225 non-neuronal cortical nuclei from 12 disease-free individuals and 6 GBM patients, in the latter analyzing both tumor and non-tumor distal regions. Somatic aneuploidy was found in approximately 15% of non-neuronal nuclei in the adult human cortex, with recurrent chromosome 16p aneuploidy in up to 4% of nuclei. In contrast, about 51% of GBM tumor nuclei showed frequent aneuploidy of chromosomes 7 and 10, consistent with known GBM profiles. Notably, non-tumor brain regions from GBM patients exhibited aneuploidy frequencies and patterns similar to controls, including recurrent 16p involvement. These findings indicate that somatic aneuploidy in non-neuronal cells is a normal feature of the adult human brain and not linked to increased GBM risk.

cancer biology↗

Multi-omic Characterization of HIV Effects at Single Cell Level across Human Brain Regions

HIV infection exerts profound and long-lasting neurodegenerative effects on the central nervous system (CNS) that can persist despite antiretroviral therapy (ART). Here, we used single-nucleus multiome sequencing to map the transcriptomic and epigenetic landscapes of postmortem human brains from 13 healthy individuals and 20 individuals with HIV who have a history of treatment with ART. Our study spanned three distinct regions--the prefrontal cortex, insular cortex, and ventral striatum--enabling a comprehensive exploration of region-specific and cross-regional perturbations. We found widespread and persistent HIV-associated transcriptional and epigenetic alterations across multiple cell types. Detailed analyses of microglia revealed state changes marked by immune activation and metabolic dysregulation, while integrative multiomic profiling of astrocytes identified multiple subpopulations, including a reactive subpopulation unique to HIV-infected brains. These findings suggest that cells from people with HIV exhibit molecular shifts that may underlie ongoing neuroinflammation and CNS dysfunction. Furthermore, cell-cell communication analyses uncovered dysregulated and pro-inflammatory interactions among glial populations, underscoring the multifaceted and enduring impact of HIV on the brain milieu. Collectively, our comprehensive atlas of HIV-associated brain changes reveals distinct glial cell states with signatures of pro-inflammatory signaling and metabolic dysregulation, providing a framework for developing targeted therapies for HIV-associated neurological dysfunction.

bioinformatics↗

Interneuron loss and microglia activation by transcriptome analyses in the basal ganglia of Tourette syndrome

Tourette syndrome (TS) is a disorder of high-order integration of sensory, motor, and cognitive functions afflicting as many as 1 in 150 children and characterized by motor hyperactivity and tics. Despite high familial recurrence rates, a few risk genes and no biomarkers have emerged as causative or predisposing factors. The syndrome is believed to originate in basal ganglia, where patterns of motor programs are encoded. Postmortem immunocytochemical analyses of brains with severe TS revealed decreases in cholinergic, fast-spiking parvalbumin, and somatostatin interneurons within the striatum (caudate and putamen nuclei). Here, we performed single cell transcriptomic and chromatin accessibility analyses of the caudate nucleus from 6 adult TS and 6 control post-mortem brains. The data reproduced the known cellular composition of the adult human striatum, including a majority of medium spiny neurons (MSN) and small populations of GABAergic and cholinergic interneurons. Comparative analysis revealed that interneurons were decreased by roughly 50% in TS brains, while no difference was observed for other cell types. Differential gene expression analysis suggested that mitochondrial function, and specifically oxidative metabolism, in MSN and synaptic function in interneurons are both impaired in TS subjects. Furthermore, such an impairment was coupled with activation of immune response pathways in microglia. Also, our data explicitly link gene expression changes to changes in cis-regulatory activity in the corresponding cell types, suggesting de-regulation as a factor for the etiology of TS. These findings expand on previous research and suggest that impaired modulation of striatal function by interneurons may be the origin of TS symptoms.

neuroscience↗

Anti-seed PNAs targeting multiple oncomiRs for brain tumor therapy

Glioblastoma (GBM) is one of the most lethal malignancies in the United States with poor survival and high recurrence rates, suggesting the need for approaches targeting the most important molecular drivers of tumor growth. Here, we aimed to simultaneously target oncomiRs 10b and 21, which have been reported to drive the aggressive growth and invasiveness of GBM. We designed short (8-mer bases) gamma-({gamma})-modified peptide nucleic acids (s{gamma}PNAs), which target the seed region of oncomiRs 10b and 21 with high affinity. We entrapped these anti-miR s{gamma}PNAs in nanoparticles (NPs) formed from a block copolymer of poly(lactic acid) and hyperbranched polyglycerol (PLA-HPG); the NPs were also functionalized with aldehydes to produce bioadhesive NPs. We have previously shown that these bioadhesive NPs (BNPs) produce superior transfection efficiency, with a tropism for tumor cells. The s{gamma}PNA BNPs showed superior anti-miR efficacy in comparison to the regular full length PNA BNPs in vitro. When combined with temozolomide, s{gamma}PNA BNPs administered via convention-enhanced delivery (CED) inhibited the growth of intracranial tumors and significantly improved the survival of animals (>120 days). RNA sequencing analysis revealed the role of vascular endothelial growth factor A (VEGFA) and integrin beta 8 (ITGB8), direct targets of both miR-10b and miR-21, in mediating the tumor growth. Hence, we established that BNPs loaded with anti-seed s{gamma}PNAs targeting multiple oncomiRs is a promising approach to improve the treatment of GBM, with a potential to personalize treatment based on tumor specific oncomiRs. SummaryO_ST_ABSTargeting oncomiRs 21 and 10b to improve GBM survivalC_ST_ABSGlioblastoma (GBM) is an aggressive malignant disorder with high recurrence rates and poor survival. Here, we aimed to simultaneously inhibit two aberrant oncomiRs--miR 21 and miR 10b--which have been previously associated with GBM invasiveness and progression. We synthesized short, gamma-modified peptide nucleic acids (s{gamma}PNA) targeted to the miR seed regions and loaded the s{gamma}PNAs into bioadhesive nanoparticles (BNPs). When the s{gamma}PNA-BNPs were added to cultured tumor cells, we observed significant reduction of target oncomiRs and increase of apoptosis in vitro. When delivered in vivo by convection-enhanced delivery, s{gamma}PNA BNPs dramatically increased the survival in two orthotopic (intracranial) mouse models of GBM. Moreover, the combination of s{gamma}PNA BNPs with temozolomide (TMZ) increased the survival of mice with GBM beyond the planned endpoint (120 days) with significant improvements in histopathology. The proposed strategy of s{gamma}PNA BNP with TMZ provides an alternative, promising approach for treatment of GBM.

cancer biology↗