Journal: ACS Chemical Neuroscience

Article Title: Fluorescence Detection of Alpha-Synuclein Aggregates in the Gut Using a Peptide Probe

doi: 10.1021/acschemneuro.6c00069

Figure Lengend Snippet: Specific α-syn antibody and probe P1 labeling of entire GI tract (esophagus, stomach, duodenum, jejunum, ileum, and colon) in transgenic mice (JAX004479). (a) Aggregated α-syn is observed in the mucosa layers and stained by both pS129 α-syn antibody and P1 (annotated with white arrows). Tissue layers are indicated by black arrows: muscularis externa (ME), submucosa (SM), and mucosa (M). Nuclei are in blue, α-syn in green, pS129 α-syn in orange, and probe in red. Scale bar represents 200 μm; (b) Total expression areas of α-syn aggregates labeled by pS129 α-syn antibody and P1 were quantified, with the highest expressions observed in the esophagus and colon; (c) High degree of colocalization (average of 0.91) was observed between pS129 α-syn antibody and probe P1 channels across all the GI tract tissues, determined by the Costes method. Manders colocalization and correlation coefficients are shown in Figure S7a ; (d) Probe positive predictive values were consistent across the respective GI tract tissues. Values on graphs are given as the mean ± SEM ( n = 3 per group); (e) P1 labeling is observed in the enteric neurons in colon tissue, marked by neuronal marker TUBB3 (green).

Article Snippet: Two strains of transgenic mice were imported from the Jackson Laboratory: (i) M83 transgenic mouse JAX004479 and (ii) double transgenic mouse JAX010799.

Techniques: Labeling, Transgenic Assay, Staining, Expressing, Marker

Journal: Translational Psychiatry

Article Title: Impairment in stimulus-response learning as a cognitive biomarker in a model of synucleinopathy

doi: 10.1038/s41398-025-03795-5

Figure Lengend Snippet: A M83 mice underwent stereotaxic surgery for inoculation of aSyn PFF-1, aSyn PFF-2 or PBS control into the right dorsal striatum. At 8 weeks post injection, they subsequently underwent a motor test battery, including assessments of motor strength, motor coordination and gait. Following completion, they were assessed for the cognitive ability to acquire stimulus-response associations, with the ‘Visuomotor Conditional Learning’ at 9-12 weeks post injection. At 16 weeks post-injection, they repeated the motor test battery, and then were processed for pathology and biochemistry. B Brain homogenates from aSyn PFF-1 and PFF-2 inoculated mice both displayed resistance to proteinase K but exhibited variable banding patterns upon digestion, as assessed by Western Blot using an antibody for total aSyn. C, D Furthermore, the same brain homogenates were evaluated by dotblots using an antibody with high affinity for aggregated aSyn (chBIIB054), revealing that while both fibril types exhibited significant binding, aSyn PFF-2 brain homogenates presented with a stronger signal (Welch’s ANOVA test, W 2, 5.34 = 7.03, p < 0.05, in which Welch-corrected unpaired t-tests revealed to be driven by a significant difference between PBS control and PFF-2 (p < 0.05). Graphics made with Biorender.com.

Article Snippet: M83 hemizygous mice (M83 + /− mice; B6; C3H-Tg[SNCA]83Vle/J) were obtained from Jackson Laboratory (004479) and maintained in-house on a C57BL/C3H background.

Techniques: Control, Injection, Battery, Western Blot, Binding Assay

Journal: Translational Psychiatry

Article Title: Impairment in stimulus-response learning as a cognitive biomarker in a model of synucleinopathy

doi: 10.1038/s41398-025-03795-5

Figure Lengend Snippet: A Schematic of Visuomotor Conditional Learning (VMCL) task. Cognitive assessments were conducted within touchscreen systems equipped with a touch-sensitive screen, a reward magazine attached to a reward pump for delivery of strawberry milkshake liquid reward and ABET cognition software ( above ). VMCL was employed to evaluate the acquisition of stimulus-response (S-R) contingencies, with subjects learning the conditional rule: “if visual stimulus A is presented, make motor response to the right-flanking window; if visual stimulus B is presented, make motor response to the flight-flanking window” ( below ). All subjects underwent VMCL testing for 20 sessions, 5-7 sessions per week. B M83 mice inoculated with aSyn PFF-1 and PFF-2 were significantly impaired at acquiring VMCL, as demonstrated by lower percent correct responses relative to PBS-inoculated mice (2-way RM ANOVA, Group x Session: main effect of group (F 2,60=10.53 , p < 0.001), main effect of session (F 2.686, 161.2=10.53 , p < 0.0001) and significant interaction (F 8,240=3.131 , p < 0.01), in which Šídák’s multiple comparisons revealed to be driven by a significant difference between PBS control and PFF-1 in sessions 2 (adj. p < 0.05), 4 (adj. p < 0.05) and 5 (adj. p < 0.05), and a significant difference between PBS control and PFF-2 in sessions 2 (adj. p < 0.01), 3 (adj. p < 0.001), 4 (adj. p < 0.01), and 5 (adj. p < 0.01)). C While all groups began at chance in Block 1 (1-way ANOVA, p > 0.05), (D) both aSyn-inoculated groups were significantly impaired relative to controls in Block 5 (1-way ANOVA, F 8.764 , p < 0.001, in which Šídák’s multiple comparisons revealed to be driven by a significant difference between PBS controls and PFF-1 (adj. p < 0.05), and between PBS controls PFF-2 (adj. p < 0.001)). E No significant difference was found in the percentage of missed trials across groups (RM Mixed-Effects Model, Group x Session: main effect of session (F 2.050,118.4= 20.55 , p < 0.0001), but no main effect of group or interaction (p > 0.05)), (F) but aSyn PFF-1 and PFF-2 mice exhibited a greater number of correction trials (2-way RM ANOVA, Group x Session: main effect of group (F 2,60= 6.008 , p < 0.01), main effect of session (F 3.240,194.4= 66.22 , p < 0.0001) but no interaction (p > 0.05)), and (G) an elevated perseveration index compared to controls (RM Mixed-Effects Model, Group x Session: main effect of group (F 2,60=4.648 , p < 0.05), main effect of session (F 3.191,171.5=24.48 , p < 0.0001), but no interaction (p > 0.05)). Furthermore, comparing task latencies, no significant difference was found in the latency to make correct choices (H) (2-way RM ANOVA: Group x Session: p > 0.05), but aSyn PFF-1 and PFF-2 mice took significantly longer to make incorrect choices (I) across VMCL acquisition compared to PBS controls (2-way RM ANOVA: Group x Session: main effect of group (F 2,60=5.384 , p < 0.01), main effect of session (F 3.202,192.1= 62.37 , p < 0.0001), and significant interaction (F 8,240=1.985 , p < 0.05), in which Šídák’s multiple comparisons revealed to be driven by a significant difference between PBS control and PFF-1 in sessions 2 (adj. p < 0.01), 3 (adj. p < 0.01) and 5 (adj. p < 0.05), and a significant difference between PBS control and PFF-2 in sessions 3 (adj. p < 0.05) and 5 (adj. p < 0.05)). No significant difference was found for the latency to collect rewards (J) (2-way RM ANOVA, Group x Session: main effect of session (F 2.275,135.9=17.67 , p < 0.0001), but no main effect of group or interaction (p > 0.05)). Data presented as Mean + SEM, * p < 0.05, ** p < 0.01, *** p < 0.001. Graphics made with Biorender.com.

Article Snippet: M83 hemizygous mice (M83 + /− mice; B6; C3H-Tg[SNCA]83Vle/J) were obtained from Jackson Laboratory (004479) and maintained in-house on a C57BL/C3H background.

Techniques: Software, Control, Blocking Assay