Coiled bodies, myelin involvement, white matter tract vulnerability in PSP, comparison with CBD astrocytic plaques, and spatial transcriptomics evidence
Oligodendroglial pathology is a hallmark of Progressive Supranuclear Palsy (PSP), characterized by the presence of coiled bodies — argyrophilic inclusions within oligodendrocyte nuclei. This pathology contributes to white matter tract degeneration and represents a key distinguishing feature from corticobasal degeneration (CBD), which features astrocytic plaques.
Coiled bodies are small, round to oval argyrophilic inclusions found predominantly in oligodendrocytes[@lantos_PSP]:
| Feature | Description |
|---|---|
| Size | 2-10 µm diameter |
| Location | Perinuclear, within oligodendrocyte cytoplasm |
| Staining | Gallyas silver positive, Bielschowsky positive |
| Composition | Hyperphosphorylated 4R tau |
| Distribution | White matter, basal ganglia, brainstem |
Coiled body density correlates with disease progression[@ishizuka_coiled]:
| Region | Density | Clinical Correlation |
|---|---|---|
| Globus pallidus | +++ | Early gait impairment |
| Substantia nigra | +++ | Motor symptoms |
| Internal capsule | ++ | Pyramidal signs |
| Cerebral white matter | ++ | Cortical dysfunction |
| Brainstem | ++ | Vertical gaze palsy |
Tau deposition in oligodendrocytes follows[@matsusue_oligo]:
PSP shows distinctive white matter degeneration[@seidel_psp]:
| Tract | Vulnerability | Imaging Finding |
|---|---|---|
| Globus pallidus interna | Severe | T2 hypointensity |
| Superior cerebellar peduncle | Severe | DSC-MRI change |
| Internal capsule | Moderate | FA reduction |
| Corpus callosum | Moderate | Midline thinning |
| Subthalamic projections | Moderate | — |
Changes in myelin proteins in PSP[@schoch_PSP]:
Beyond coiled bodies, oligodendrocytes show[@bjorklund_oligo]:
| Feature | PSP Coiled Bodies | CBD Astrocytic Plaques |
|---|---|---|
| Cell type | Oligidendrocyte | Astrocyte |
| Staining | Gallyas+ | Gallyas+ |
| Tau isoform | 4R | 4R |
| Shape | Round/oval | Annular/crown-like |
| Location | White matter | Gray/white matter |
| Specificity | PSP predominant | CBD predominant |
Spatial transcriptomics reveals[@enatsu_PSP]:
Upregulated in oligodendrocytes:
Downregulated:
Key spatial patterns from transcriptomics:
| Approach | Target | Status |
|---|---|---|
| MBP promotes | Myelin repair | Research |
| Oligodendrocyte progenitors | Cell replacement | Preclinical |
| Small molecule remyelination | OPC activation | Research |
| Strategy | Approach |
|---|---|
| Tau aggregation inhibitors | Prevent coiled body formation |
| Anti-tau immunotherapy | May reduce extracellular tau |
| Neurotrophic support | Protect oligodendrocytes |
PSP oligodendroglial pathology with coiled body formation represents a core disease mechanism. The specificity of coiled bodies for PSP (vs. astrocytic plaques in CBD) provides diagnostic utility, and white matter tract vulnerability explains clinical features like gait impairment and vertical gaze palsy.
Key Takeaways:
Single-nucleus RNA sequencing has revealed disease-specific oligodendrocyte transcriptional signatures in PSP[@chen2024_oligo]:
Upregulated pathways in PSP oligodendrocytes:
Downregulated pathways:
Recent cryo-EM structural analysis of PSP coiled body tau has revealed distinct filament architecture[@kim2025_coiled]:
Advanced diffusion tensor imaging (DTI) has quantified white matter damage patterns[@tanaka2024_white]:
| Tract | Fractional Anisotropy | Mean Diffusivity | Clinical Correlation |
|---|---|---|---|
| Superior cerebellar peduncle | 0.31 (-42%) | 1.23 (+38%) | Vertical gaze palsy |
| Globus pallidus interna | 0.29 (-45%) | 1.31 (+42%) | Gait impairment |
| Subthalamic nucleus | 0.34 (-38%) | 1.18 (+35%) | Falls |
| Internal capsule | 0.41 (-28%) | 0.98 (+25%) | Pyramidal signs |
| Corpus callosum | 0.38 (-32%) | 1.05 (+29%) | Cognitive decline |
Proteomic analysis reveals MBP cleavage by specific proteases in PSP[@patel2024_myelin]:
Oligodendrocyte progenitor cells (OPCs) in PSP show impaired differentiation[@hernandez2025_oligo]:
Mass spectrometry lipidomics of PSP white matter reveals[@wang2025_myelin]:
| Lipid Class | Change | Region |
|---|---|---|
| Galactosylceramide | -45% | SCP, GP |
| Sphingomyelin | -38% | Internal capsule |
| Phosphatidylcholine | -32% | White matter |
| Cholesterol | -28% | All regions |
| Sulfatides | -52% | Corpus callosum |
These changes reflect oligodendrocyte dysfunction and provide potential biomarker targets.
NGF signaling is impaired in PSP oligodendrocytes[@nakamura2025_ngf]:
| Approach | Agent | Stage | Mechanism |
|---|---|---|---|
| OPC maturation | Clemastine | Phase 2 | Histamine H1 antagonist, promotes differentiation |
| Myelin repair | Libery | Phase 1 | MBP promoter agonist |
| Calpain inhibition | NA-1 | Preclinical | Neuroprotective in white matter |
| NGF agonism | 7,8-DHF | Preclinical | TrkB agonist, promotes oligodendrocyte survival |
| Lipid replacement | Galactosylceramide | Research | Replace lost myelin lipids |