Biology subjects

roybon, l.

Publications and source records attributed to roybon, l..

4 recordsLinked to original sources

bioRxiv2026

A convergent metabolic-kinase signaling axis links Parkinson s disease and multiple system atrophy

Parkinsons disease (PD) and multiple system atrophy (MSA) are alpha-synucleinopathies with overlapping clinical phenotypes but distinct cellular pathological hallmarks. Whether these disorders share upstream molecular changes beyond alpha-synuclein aggregation remains unresolved. Here, we generated induced pluripotent stem cell (iPSC)-derived midbrain spheroids containing dopaminergic neurons from individuals with monogenic PD, idiopathic PD, MSA, and controls, and applied integrated proteomics, metabolomics, and phosphoproteomics to define disease-associated biochemical programs and their regulatory architecture. Despite their distinct etiologies, PD and MSA spheroids displayed highly concordant molecular remodeling, with cellular metabolism emerging as the dominant shared disturbance. Network analyses identified coordinated changes in central carbon metabolism, oxidative phosphorylation, branched-chain amino acid catabolism, pantothenate/CoA metabolism, and lipid remodeling, coupled to phosphorylation-driven rewiring of MAPK, mTOR, AMPK, PKA/PKC, and second-messenger kinase programs. Importantly, these metabolic and signaling axes were also prominent in postmortem substantia nigra from PD and MSA donors, supporting conservation between patient-derived models and postmortem brain tissue. Together, these data identify metabolic dysregulation as a unifying molecular feature across PD and MSA and suggesting phosphorylation-linked metabolic control nodes as candidate entry points for therapeutic intervention. HighlightsO_LIPD and MSA exhibit molecular programs that extend beyond alpha-synuclein pathology. C_LIO_LIProteomics identifies metabolism as the dominant shared disease axis across PD and MSA. C_LIO_LIMetabolomics resolves a coupled glucose-TCA-BCAA-CoA-lipid remodeling program in PD and MSA. C_LIO_LIPhosphorylation-centered kinase networks link signaling rewiring to metabolic bottlenecks. C_LIO_LIShared metabolic features are conserved between patient iPSC-derived midbrain spheroids and substantia nigra. C_LI Graphic abstract (generated using BioRender) O_FIG O_LINKSMALLFIG WIDTH=191 HEIGHT=200 SRC="FIGDIR/small/731777v1_ufig1.gif" ALT="Figure 1"> View larger version (77K): org.highwire.dtl.DTLVardef@1748e51org.highwire.dtl.DTLVardef@12b8f91org.highwire.dtl.DTLVardef@de8893org.highwire.dtl.DTLVardef@1d89ea1_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2025

Redefining Parkinson's Disease by Dysregulated Genetic Networks in Distinct Cell Types

Parkinsons disease (PD) is classically linked to dopaminergic neuron loss, but emerging evidence suggests broader cellular involvement. Here we show that PD risk variants converge on distinct molecular networks across specific brain cell types, enabling stratification of patients into six subgroups: dopaminergic, oligodendrocyte progenitor cells (O), excitatory (E), dopaminergic/excitatory, dopaminergic/oligodendrocyte and other. While all subgroups exhibit motor symptoms, the E-group individuals also display more severe non-motor symptoms, including dementia, hyposmia, and REM sleep behavior disorder. The O-group individuals exhibit reduced myelin integrity, as demonstrated by diffusion tensor imaging, implicating NRG6 (formerly C1orf56), a previously uncharacterized high-risk PD gene. We show that NRG6 encodes a conserved epidermal growth factor-like domain structurally and functionally analogous to neuregulin-1, which is critical for oligodendrocyte development and myelination. These findings redefine the cellular architecture of PD vulnerability and identify neuregulin-like signaling in oligodendrocytes as a potential contributor to non-motor symptoms.

neuroscience↗

bioRxiv2023

TNFa hinders FGF4 efficacy to mitigate ALS astrocyte dysfunction and cGAS-STING pathway-induced innate immune reactivity

Astrocytes play an important role in the onset and progression of amyotrophic lateral sclerosis (ALS), a fatal disorder characterized by the relentless degeneration of motor neurons (MNs) in the central nervous system. Despite evidence showing that ALS astrocytes are toxic to MNs, little is understood about the earliest pathological changes that lead to their neurotoxic phenotype. In this study, we generated human astrocytes from induced pluripotent stem cells (iPSCs) harboring the ALS-associated A4V mutation in superoxide dismutase 1 (SOD1), to examine cellular pathways and network changes similar to early stages of the disease. By using proteomics as a molecular indicator, we observed significant alterations in the levels of proteins linked to ALS pathology and the cGAS-STING pathway-induced innate immunity. Interestingly, we found that the protein profile of reactive ALS astrocytes differed from that of wildtype astrocytes treated with the pro-inflammatory cytokine TNF. Notably, we showed that fibroblast growth factor 4 (FGF4) reversed ALS astrocyte dysfunction and reactivity, but failed to provide protection to MNs when expressed in the spinal cord of the SOD1G93A mouse model of ALS. Further analysis showed that ALS astrocyte reactivity which was rescued by FGF4 was abrogated by TNF. The latter is capable of exacerbating the dysfunction and reactivity of ALS astrocytes compared to control. Our data show that iPSC-derived ALS astrocytes are dysfunctional and spontaneously exhibit a reactive phenotype when generated from iPSCs. This suggests that this phenotype may resemble the early stages of the disease. Our data also demonstrate that reducing mutant astrocyte reactivity in vivo using FGF4 is not sufficient to prevent MN death in a mouse model of ALS. To mitigate ALS, future studies should investigate whether dual therapies that both lower astrocyte reactivity and reverse disease-associated cellular dysfunction could prevent MN death. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=193 SRC="FIGDIR/small/566131v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@9490b5org.highwire.dtl.DTLVardef@1a897e5org.highwire.dtl.DTLVardef@18c4578org.highwire.dtl.DTLVardef@24da7d_HPS_FORMAT_FIGEXP M_FIG C_FIG Highlights- ALS astrocytes are dysfunctional and reactive compared to wildtype astrocytes - FGF4 reverses ALS astrocyte dysfunction and reactivity - FGF4 lowers ALS astrocyte reactivity in vivo but fails to protect ALS motor neurons from death - ALS astrocyte reactivity rescued by FGF4 is attenuated by TNF

neuroscience↗

bioRxiv2023

Proteomic analysis across patient iPSC-based models and human post-mortem hippocampal tissue reveals early cellular dysfunction, progression, and prion-like spread of Alzheimer s disease pathogenesis

The hippocampus is a primary region affected in Alzheimers disease (AD). Because AD postmortem brain tissue is not available prior to symptomatic stage, we lack understanding of early cellular pathogenic mechanisms. To address this issue, we examined the cellular origin and progression of AD pathogenesis in patient-based model systems including iPSC-derived brain cells transplanted into the mouse brain hippocampus. Notably, proteomic analysis of the graft enabled the identification of proteomic alterations in AD patient brain cells, associated with increased levels of {beta}-sheet structures and A{beta}42 peptides. Interestingly, the host cells surrounding the AD graft also presented alterations in cellular biological pathways. Furthermore, proteomic analysis across human iPSC-based models and human post-mortem hippocampal tissue projected coherent longitudinal cellular changes indicative of disease progression from early to end stage AD. Our data showcase patient-based models to study the cellular origin, progression, and prion-like spread of AD pathogenesis. Highlights- AD patient iPSC-derived brain cells survive in the hippocampus of immunodeficient mice 6 months post-transplantation. - Proteomic analysis of the grafts reveals profound alterations in cellular biological pathways in iPSC-derived hippocampal cells despite absence of senile plaques. - Proteomic alterations within transplanted AD iPSC-derived hippocampal cells are reminiscent of early/prodromal AD. - AD-grafted cells induce proteomic changes in host mouse cells.

neuroscience↗