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Inflammation (infection, demyelination)T1-weighted (axial brain MRI)T2-weighted (axial brain MRI)Flair (axial brain MRI)
very sensitive to pathology and makes the differentiation between CSF and an abnormality much easier.

MRI in PD

{Booth, 2015 #1745} REVIEW
  • Structural abnormalities on MR imaging in PD are subtle and, other than nonspecific putaminal atrophy, are found in ~20% of patients with PD.21
  • There may be nonspecific abnormalities of SN, including "smudging" of the hypointensity in SN toward the red nucleus on T2-weighted sequences (Fig 3)22 or increased signal with gray matter-suppressed T1-weighted inversion recovery sequences (Fig 4).23
  • Voxel-based morphometry might reveal nonspecific gray matter loss of limbic, paralimbic, and prefrontal cortices.24
  • Pathologic diffusion imaging findings in patients with PD are very rare25;

MRS in PD

{Booth, 2015 #1745} REVIEW
  • elevated ADC (apparent diffusion coefficient) may be seen in the region of the olfactory tracts in patients with PD compared with healthy controls.251H-MRS studies are nonspecific, showing reduced NAA/Cr and NAA/choline ratios in the basal ganglia, reflecting neuronal loss.26

MSA

Good review: {Stefanova, 2023 #2300}

Animal models of MSA

promoter
(PLP)-hα-syn transgenic mouse ('Poewe MSA mouse model')PLP (proteolipid protein) Promoter, (transgenic protein was detected in oligodendrocytes but in no other brain cell type.),
=CSF aSyn level
- FIG2A) Overexpresses human WT α-syn specifically in oligodendrocytes
- (total) Asyn: ~6 fold increase in whole brain (ELISA) (vs WT)
- FIG2B) soluble/insoluble, monomer/oligomer 모두 ↑ (Syn1, wb)
,
- GCI-like structures (oligodendrocyte에는 확실, 그러나 neuron, astrocyte, microglia에는 겨우 작은 human aSyn반 보이는 정도임)

{Refolo, 2018 #1419} - GCI-like structures: with variable density and (wide-spread) distribution throughout the brain (Fig. 1f, striatum, SN, pontine nuclei, cbll cortex, inf olives 주:cerebral cortex는 안 감!) even at very early age (아마 2m부터?). at very early age. The GCI-load does not change with aging but caudal쪽이 더 심함.
- (fig 8) 6m부터 (Soluble) oligomeric aSyn 생기며, ↑microglia, ↓DA, ↓motor function
- the total level of (soluble & insoluble) monomeric aSyn is stable over time), -

- Olivopontocerebellar motor loops remained spared (의미?), Cerebellar Purkinje 와 pontine cell loss는 x (GCI는 있는데?)
- Demyelination is not typically found
- Brain wt loss since 9m old (fig 3b),
- ↓ neurons and oligodendrocytes in SC (FIG3)
- GCI O, asyn accumulations in neuropil (f, axonal spheroids in cortex (indicating axonal degeneration, fig4e), gliosis o, insoluble aSyn accumulation, demyelination,
- Remarkable gliosis in brain and spinal cord (fig 4g & h), axonal degeneration in cbll (GAP, fig4i, 24 m, cerebral WM)
- GCI like inclusion & aSyn accumulation in oligodendrocytes and neuropil in (fig4b, 24 m, cerebral WM)
- Axonal spheroids in cerebral cortex (24m, fig4e,f),
- Degenerated myelin sheaths with degenerating axons in spinal cord (fig 6e)
- Loss of myelinated axons in spinal cord (fig 6j)
(MGI:3604008) TSHO does not have a license and did not used in the past research.

{Heras-Garvin, 2020 #1121, 2nd}
{Yazawa, 2005 #1440, original'
M2 mice, (CNP)-hα-syn transgenic mouse2',3'-Cyclic-nucleotide 3'-phosphodiesterase CNP promoter [81 model under the ]. overexpresses human α-syn in oligodendrocytes,
- Fig1b: =total aSyn (SNL1, WB)

↓ ROTArod test, ↓ wire test (grip strength)
viral-based animal models overexpressing α-syn in oligodendrocytes in rats and NHPs [77,79]
mouse model of adult-onset MSA based on the Cre-loxP system, which expresses inducible α-syn in oligodendrocytes [82].
MBP-aSyn mouseUbhi K, Rockenstein E, Mante M, Inglis C, Adame A, Patrick C, Whitney K, Masliah E (2010) Neurodegeneration in a transgenic mouse model of MSA is associated with altered expression of oligodendroglial-derived neurotrophic factors. J Neurosci 30:6236-6246
(f) Hasegawa 2016)Mice injected with MSA brain homogenate develop neuronal a-syn pathology, but not in oligodendrocytes.

aSyn in MSA

Brain aSyn in MSA

{Schweighauser, 2020 #2060}
seeding capacity:
GCI-aSyn vs LB-aSyn
The cores of α-syn filaments extracted from the cerebellum of MSA patients or assembled from recombinant protein in vitro encompass around 70 amino acids, extending approximately from residues 30-100 (30).
In vitro:

GCI α-syn has been reported to be approximately three orders of magnitude more potent than Lewy body α-syn in seeding aggregation of α-syn (36). biologically distinct. 이의 원분 {Peng, 2018 #2062}: GCI-α-Syn forms more compact structures and is ~1,000-fold more potent than LB-α-Syn in seeding α-Syn aggregation
In vivo:
{Prusiner, 2015 #2063} Inoculation of a-syn aggregates from MSA but not PD cases induced deposition of phosphorylated a-syn
Solubility in SDS distinguishes a-syn filaments of MSA from those of DLB (44).

CSF aSyn in MSA

Js: CSF aSyn 은 MSA 에서 정상과 차이가 없고, exosome aSyn 은 결과가 inconsistent 하니, 유용없으나, tak-341 의 response 로서 감소를 보는 의미는 있겠다.
{Ateno, 2012 #1467} (boxplot of alpha-synuclein (pg/ml) 0-400 across Control n=11, AD n=9, DLB n=6, PD n=11, MSA n=12; significance brackets with * p<0.05, ** p<0.01, *** p<0.001).
FIGURE 1. Alpha-synuclein concentration in the cerebrospinal fluid in degenerative neurological diseases. Statistical analysis was made by the Mann-Whitney U test. AD indicates Alzheimer disease; DLB, dementia with Lewy bodies; MSA, multiple system atrophy; PD, Parkinson disease.
{Mavroudis, 2020 #1468}
anlysis
, CSF aSyn levels were significantly different in LBD compared with AD, but no statistical difference was found between PDD, MSA, PSP, and FTD. (HC와 비교는 안 함)
{ga, 2018 #1623} reviewTotal α-syn in CSF have been often examined, but with inconsistent results. Of nine studies using antemortem CSF, six revealed ↓ total α-syn in MSA patients vs control subjects, while three other studies did not show difference between the two groups (table 1).
{ulds, 2012 #2455} 76[Postmortem] ...

Uncertain Spans

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  • “{ga, 2018 #1623}” and “{ulds, 2012 #2455}” — the citation prefixes are clipped at the left edge of the page, only the trailing characters are visible.
  • “GCI O, asyn accumulations in neuropil (f,” — the trailing single character f, is likely a section/figure tag truncated at the row boundary; the actual figure number is not unambiguously readable.
  • “{Yazawa, 2005 #1440, original’” — the source line ends with a stray apostrophe in the rendered cell; whether the closing brace is present is unclear from the visible crop.