Neuroscience
Abstract
While clinical trials of human pluripotent stem cell–derived midbrain dopamine (mDA) neuron precursor grafts for Parkinson’s disease (PD) are ongoing, current protocols remain suboptimal. In particular, the yield of TH+ mDA neurons after in vivo grafting and the expression of certain mDA neuron and subtype-specific markers require improvement. Single-cell transcriptomic analyses of grafts have revealed low proportions of mDA neurons and substantial off-target contamination. Here, we present an optimized mDA neuron differentiation strategy that builds on our clinical-grade (“Boost”) protocol by adding FGF18 and IWP2 treatment (“Boost+”) at the neurogenesis stage. Boost+ mDA neurons show higher expression of EN1, PITX3, and ALDH1A1. Improvements in mDA neuron yield and transcriptional similarity to primary mDA neurons are observed in vitro and following transplantation. Single-nucleus RNA sequencing demonstrates enrichment of A9 mDA neurons within Boost+ grafts. Functional studies in vitro demonstrate increased dopamine production and release and improved electrophysiological properties. In vivo analyses show higher percentages of TH+ mDA neurons, resulting in efficient rescue of amphetamine-induced rotation behavior in the 6-OHDA rat model and rescue of deficits in some nondrug-induced assays, including the ladder rung assay, which are not improved by Boost mDA neurons. The Boost+ conditions present an optimized differentiation protocol with advantages for disease modeling and mDA neuron grafting paradigms.
Authors
Tae Wan Kim, Jinghua Piao, Vittoria D. Bocchi, So Yeon Koo, Se Joon Choi, Fayzan Chaudhry, Donghe Yang, Hyein S. Cho, Emiliano Hergenreder, Lucia Ruiz Perera, Subhashini Joshi, Zaki Abou Mrad, Nidia Claros, Shkurte Ademi Donohue, Yeong Eun Im, Hyo Jae Jeong, Anika K. Frank, Ryan M. Walsh, Eugene V. Mosharov, Doron Betel, Viviane Tabar, Lorenz Studer
Abstract
Skraban-Deardorff syndrome, a rare neurodevelopmental disorder caused by WD repeat domain 26 (WDR26) haploinsufficiency, is characterized by intellectual disability, seizures, autistic-like behaviors, and craniofacial anomalies. Despite its genetic association with variants disrupting the C-terminal to LisH (CTLH) E3 ubiquitin ligase complex, the molecular mechanisms linking WDR26 dysfunction to neurodevelopmental deficits remain unclear. Here, we demonstrate that Wdr26 heterozygous-KO mice (Wdr26+/–) recapitulated core clinical features of the syndrome, including learning and memory impairments, social dysfunction, heightened seizure susceptibility, and motor deficits, alongside rare craniofacial and dental abnormalities. Mechanistically, Wdr26 haploinsufficiency stabilized RUNX1 translocation partner 1 (RUNX1T1), a transcriptional coactivator critical for neuronal differentiation, by impairing its ubiquitination and proteasomal degradation, consequently disrupting the level of microtubule-associated protein 2 (MAP2), a key regulator of dendritic architecture and synaptic plasticity. Early intervention in neonatal Wdr26+/– mice (P0.5) using AAV-shRNA–mediated Runx1t1 knockdown reversed MAP2 overexpression and behavioral deficits. Notably, the antipsychotic risperidone ameliorated cognitive and social impairments in Wdr26+/– mice by upregulating WDR26 levels, suggesting a potential therapeutic avenue. Our findings not only establish the animal model as a robust preclinical tool but also define the WDR26/RUNX1T1/MAP2 regulatory axis as pivotal to the syndrome’s pathogenesis, while identifying actionable therapeutic targets.
Authors
Xingyun Xu, Yaohui Zhou, Shiyao Xu, Hongjie Zhou, Xuexia Lin, Yuhao Luo, Yu Xu, Zhigang Miao, Wei Ge, Hao Yang, Xingshun Xu
Abstract
Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disease marked by progressive motor deficits and Purkinje cell (PC) degeneration, driven by polyglutamine expansion in ataxin-1. While oligodendroglial dysfunction precedes PC loss, its direct contribution toward SCA1 pathogenesis remains unclear. Here, using an oligodendroglia-specific SCA1 conditional knock-in mouse model, we demonstrate that mutant ataxin-1 in oligodendrocytes is sufficient to drive aspects of SCA1-related pathology, including dysregulated myelination, PC axonal shrinkage, and torpedo formation, ultimately impairing motor coordination. Transcriptomic analysis uncovers cerebellar oligodendrocyte subtypes with distinct gene expression signatures and aberrant abundance that contribute to demyelination. This, compounded by a progressive decline in the neuroprotective functions of a cerebellar-specific oligodendrocyte subtype, establishes a critical link between demyelination, axo-myelinic dysfunction, and axonal pathology in SCA1. Upstream transcriptional regulator analysis in oligodendroglia identifies TCF7L2 and HTT as key mediators of oligodendroglial dysfunction in SCA1, suggesting shared pathogenic mechanisms with other polyglutamine diseases. Collectively, these findings establish oligodendroglia as key mediators of SCA1 pathogenesis and underscore their critical role in preserving PC axonal integrity.
Authors
Changwoo Lee, Rosalie M. Grijalva, Leon Tejwani, Eunwoo Bae, Alison Chase, Hannah Ro, Hannah Kim, Victor Olmos, James P. Orengo, Janghoo Lim
Abstract
Neuropathic pain affects over 20 million people in the United States, and painful diabetic neuropathy (PDN), a common complication of diabetes, is among its most prevalent and treatment-resistant forms. Although PDN is characterized by nociceptor dysfunction, the upstream peripheral mechanisms remain incompletely understood. While dorsal root ganglion (DRG) nociceptor hyperexcitability is a hallmark of PDN, emerging evidence suggests that non-neuronal skin cells may modulate nociceptor function. Here, we investigated whether epidermal Langerhans cells (LCs) contribute to neuropathic pain in PDN through neuroimmune signaling. Using a clinically relevant high-fat diet (HFD) mouse model, transgenic LC ablation, behavioral assays, human skin biopsies, and single-cell RNA sequencing of epidermis and DRG, we found that LC density increased in male diabetic mice in parallel with mechanical allodynia. In human PDN skin, LCs exhibited increased volume and dendritic complexity correlating with diabetes duration. Genetic depletion of LCs prevented mechanical allodynia and spontaneous pain-like behavior in male, but not female, HFD mice, revealing a sex-dependent contribution. Single-cell and interactome analyses identified male-specific inflammatory LC programs, including upregulation of chemokine signaling pathways. Consistently, LC secretome profiling showed increased CCL2 release, and local CCR2 blockade reversed allodynia. These findings identify epidermal LCs as peripheral regulators of PDN pain and highlight sex-dependent chemokine-mediated neuron-immune communication at the skin-nerve interface.
Authors
Paola Pacifico, Dale George, Nirupa D. Jayaraj, Dongjun Ren, James S. Coy-Dibley, Abdelhak A. Belmadani, Sofia Veronesi, Mirna Andelic, Daniele Cartelli, Grazia Devigili, Raffaella Lombardi, Giuseppe Lauria Pinter, Amy S. Paller, Richard J. Miller, Daniela M. Menichella
Abstract
Western diets (WD), high in saturated fats such as palmitic acid (PA), promote enteric neurodegeneration and motility disorders. Using murine models, in vitro systems, and human myenteric ganglia, we investigated whether WD and PA drive iron-dependent ferroptotic injury in the enteric nervous system. Mice were fed control diet (CD) or WD for 12 weeks, with or without systemic AAV9-MaCPNS2 delivery of Nfe2l2 to enteric neurons. Colonic motility was assessed by bead-expulsion assay. Ferroptosis was assessed using convergent readouts including iron dysregulation (TfR1, FTH-1, labile and mitochondrial Fe2+), lipid peroxidation (C11-BODIPY and 4-HNE), GPX4 suppression, and pharmacologic inhibition by ferrostatin-1 (Fer-1) in primary enteric neurons, murine myenteric plexuses, and human networks of myenteric ganglia (nhMPG). WD-fed mice exhibited delayed colonic transit, increased TfR1 and FTH-1, and vulnerability of nNOS neurons; these changes were reversed by Nfe2l2 overexpression. RNA-seq of PA-treated IM-FEN neuronal cells revealed disrupted of neurotransmitter signaling, reduced mitochondrial and antioxidant programs, and increased iron import and lipid peroxidation signatures. PA increased labile iron, mitochondrial ROS, membrane depolarization, Ca2+ dysregulation, 4-HNE, and Mfrn2, while Fer-1 preserved mitochondrial integrity, viability, and ENS function. In human nhMPG, PA induced enteric neuronal iron loading and ferroptosis, supporting translational relevance to diet-associated enteric neuropathy.
Authors
Arun Balasubramaniam, Dmitrii Pavlov, Yunpeng Du, Jeremy Reeves, Alan Harzman, Yunshan Liu, Francesca Cingolani, Xinxu Yuan, Jay M. Patel, Simon Musyoka Mwangi, Peijian He, C. Michael Hart, Wenhui Hu, Fievos L. Christofi, Shanthi Srinivasan
Abstract
BORCS5 encodes a subunit of the BLOC-One-Related Complex (BORC), which is known to promote anterograde movement and fusion of lysosomes. We identified 16 individuals from nine families with bi-allelic BORCS5 variants, revealing a spectrum of neurodevelopmental and neurodegenerative phenotypes. Carriers of homozygous protein-truncating variants (PTVs), resulting in complete loss of BORCS5, presented with prenatally lethal arthrogryposis multiplex congenita, brain malformations, and neuropathological evidence of neuroaxonal dystrophy. Individuals with missense or splice-site variants presented differently, with microcephaly, developmental epileptic encephalopathy, optic atrophy, spasticity, and progressive movement disorders. In this group, brain MRI showed diffuse hypomyelination, corpus callosum abnormalities, as well as progressive global cerebral atrophy, consistent with neurodegeneration. Borcs5 knockout in zebrafish exhibited microcephaly, motor deficits, and increased seizure susceptibility, mirroring the patients’ clinical presentation. At the cellular level, only BORCS5 PTVs, but not missense variants, led to perinuclear lysosomal clustering and impaired lysosomal axonal trafficking in induced pluripotential stem cell-derived forebrain neurons. However, both PTVs and missense variants were associated with reduced lysosomal proteolysis and activity of lysosomal hydrolases glucocerebrosidase and cathepsin B, indicating lysosomal dysfunction. Our study reveals a role for BORCS5 in modulation of lysosomal function, in addition to its known role in lysosome movement and fusion, possibly underlying the diverse clinical manifestations in individuals with BORCS5-related disorders.
Authors
Niccolò E. Mencacci, Georgia Minakaki, Reza Maroofian, Raffaella De Pace, Adeline Paimboeuf, Tiago Branco Fonseca, Tatiana Abramova, Patrick Shannon, David Chitayat, Francesca Magrinelli, Wesley J. Peng, Diptaman Chatterjee, Sara H. Eldessouky, Julia Baptista, Tamas Marton, Julie Vogt, Juan Dario Ortigoza-Escobar, Loreto Martorell, Marta Gómez-Chiari, Ingrid M. Wentzensen, Erik-Jan Kamsteeg, Maha S. Zaki, Annarita Scardamaglia, Giovanni Zifarelli, Zuhair Nasser Al-Hassnan, Elka Miller, Shiri Shinar, Lova S. Matsa, Sri Hari Chandan Appikonda, Ghada A. Otaify, Khalid Al-Thihli, Almundher Al-Maawali, Michael Schwake, Mariasavina Severino, Henry Houlden, Shunmoogum A. Patten, Juan S. Bonifacino, Kailash P. Bhatia, Dimitri Krainc
Abstract
Primary and metastatic brain tumors exhibit resistance to immunotherapies that demonstrate efficacy in peripheral cancer settings. While many immunotherapies aim to enhance CD8+ T cell infiltration and functionality in established tumors, identification of neoantigens support emerging immunopreventative tactics against brain cancer. Functionally potent tissue-resident memory CD8+ T cells (TRM) can be generated in the brain following peripheral infection or vaccination. However, the ability of brain TRM to prevent intracranial malignancy remains unknown. Here, mice were seeded with tumor-specific or bystander brain TRM via peripheral infection prior to depletion of circulating memory T cells (TCIRCM) and subsequent brain tumor challenge. Tumor-specific brain TRM durably protected mice against intracranial malignancy even in the absence TCIRCM. These brain TRM persisted in tumor-surviving mice and protected against a second antigen-matched challenge. Importantly, a translationally-relevant mRNA-lipid nanoparticle (LNP) vaccine phenocopied peripheral infection-induced outcomes, generating functional brain TRM that controlled tumor growth. Altogether, this work points to the utility of brain TRM in cancer immunoprevention, supporting the development of antitumor mRNA-LNP vaccines to bolster brain immunity.
Authors
Madison R. Mix, Cassie M. Sievers, Mariah Hassert, Shravan Kumar Kannan, Lecia L. Pewe, Sunny C. Huang, Rui He, Cori E. Fain, Mohammad Heidarian, Lisa S. Hancox, Sahaana A. Arumugam, Terry G. Beltz, Fang Jin, Aaron J. Johnson, Calvin S. Carter, Noah S. Butler, Aliasger K. Salem, Vladimir P. Badovinac, John T. Harty
Abstract
Loss-of-function mutations in DNAJC6, encoding the co-chaperone auxilin (HSP40 family), cause familial juvenile-onset Parkinson’s disease (PD). Given the chaperone role of DNAJC6 in cellular homeostasis in adult neurons, we hypothesized that DNAJC6 dysfunction may not be limited to juvenile-onset disorders but could also be associated with adult-onset brain diseases. Here, we show that DNAJC6 expression is significantly downregulated in postmortem substantia nigra tissues and transcriptomic datasets from patients with late-onset sporadic PD. Consistently, human pluripotent stem cell–derived midbrain cultures exhibited reduced DNAJC6 expression under multiple PD-associated conditions. Mechanistically, DNAJC6 loss resulted from impaired transcription mediated by midbrain-specific factors NURR1/FOXA2 and reduced protein stability regulated by LRRK2. Beyond neurons, DNAJC6 was robustly expressed in astrocytes and similarly downregulated in sporadic PD contexts. Astrocytic DNAJC6 deficiency impaired phagocytic, autolysosomal, and mitochondrial functions while promoting a pro-inflammatory phenotype, thereby exacerbating neurodegenerative pathology. Importantly, epigenetic restoration of DNAJC6 in neurons and astrocytes using a CRISPRa-AAV9 system in the substantia nigra of an α-synuclein–induced PD mouse model alleviated behavioral deficits and neuropathology. These findings provide evidence that DNAJC6 dysregulation is associated with pathogenic processes in sporadic PD and suggest that targeting neuronal and astrocytic DNAJC6 could represent a potential disease-modifying strategy.
Authors
Wahyu Handoko Wibowo Darsono, Yeongran Hwang, Erica Valencia, Leonardo Tejo Gunawan, Seung Jae Hyeon, Hoon Ryu, Thor D. Stein, Mi-Yoon Chang, Noviana Wulansari, Sang-Hun Lee
Abstract
Traumatic brain injury (TBI) disproportionately affects the elderly, yet the underlying mechanisms remain unclear. Here, we demonstrate that aged TBI brains predominantly harbor pro-inflammatory NLRP3+ microglia, in stark contrast to the neuroprotective Lysozyme+ microglia prevalent in young TBI brains. This age-dependent microglial dichotomy correlates with elevated mortality and impaired recovery in aged TBI mice. By leveraging an integrative multi-omics approach combined with metabolomics and epigenome analysis, we identify a previously unrecognized link between enhanced glycolysis and pro-inflammatory chromatin landscape in NLRP3+ microglia. Further investigation identifies ELF1 as a key transcription factor driving NLRP3+ microglia formation. Importantly, ablation of ELF1 reverses age-associated microglial dysfunction and improves TBI outcomes. Finally, we discover that Imeglimin, a clinically approved antihyperglycemic agent capable of crossing the blood brain barrier, inhibits ELF1 and reverses microglial phenotype, reducing acute mortality rate and leading to improved functional recovery of aged TBI mice. Our work elucidates the mechanistic basis of age-dependent TBI outcomes, reveals the crosstalk between metabolic rewiring and epigenetic regulation in microglial aging, and identifies ELF1 as a promising therapeutic target for improving TBI outcome.
Authors
Zhichao Lu, Yi Shuai, Chenxing Wang, Zongheng Liu, Ziheng Wang, Qianqian Liu, Rui Jiang, Jue Zhu, Yongqi Zhu, Weiquan Liao, Xingjia Zhu, Jingwei Zhao, Kaibin Shi, Wei Shi, Peipei Gong
Abstract
Sleep disturbances are among the most prevalent clinical features of FOXP1 syndrome, yet their nature and underlying mechanisms remain unclear. Here, we report that individuals with FOXP1 syndrome suffer from insomnia with sleep maintenance problems and early waking. Consistently, common variants in FOXP genes were associated with insomnia symptoms and short sleep. These sleep disturbances were recapitulated in Drosophila FoxP mutants, which exhibit severely fragmented and reduced sleep. FoxP loss also led to circadian arrhythmicity and impaired the plasticity of neuropeptide pigment dispersing factor–secreting (PDF-secreting) neurons in a non-cell-autonomous manner. FoxP was required during development for adult sleep integrity, particularly in peptidergic neurons. Transcriptomic analyses revealed a dysregulation of genes involved in peptidergic signaling, including hugin. FoxP was expressed in hugin+ neurons (afferent to PDF-secreting neurons) during development, and its knockdown in these cells was sufficient to induce sleep fragmentation. Our findings establish an evolutionarily conserved role for FOXP proteins in the peptidergic regulation of sleep.
Authors
Mireia Coll-Tané, Ilse Eidhof, Jie Han, Nicholas Raun, Lara V. van Renssen, Simon E. Fisher, Matthew S. Kayser, Tjitske Kleefstra, Sigrid Pillen, Caitlin M. Hudac, Jordi Mayneris-Perxachs, Marieke Klein, Saskia Koene, Anna Castells-Nobau, Annette Schenck
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)