Chronic PPARγ Stimulation Shifts Amyloidosis to Higher Fibrillarity but Improves Cognition.

We undertook longitudinal β-amyloid positron emission tomography (Aβ-PET) imaging as a translational tool for monitoring of chronic treatment with the peroxisome proliferator-activated receptor gamma (PPARγ) agonist pioglitazone in Aβ model mice. We thus tested the hypothesis this treatment would rescue from increases of the Aβ-PET signal while promoting spatial learning and preservation of synaptic density. Here, we investigated longitudinally for 5 months PS2APP mice (N = 23; baseline age: 8 months) and App NL-G-F mice (N = 37; baseline age: 5 months) using Aβ-PET. Groups of mice were treated with pioglitazone or vehicle during the follow-up interval. We tested spatial memory performance and confirmed terminal PET findings by immunohistochemical and biochemistry analyses. Surprisingly, Aβ-PET and immunohistochemistry revealed a shift toward higher fibrillary composition of Aβ-plaques during upon chronic pioglitazone treatment. Nonetheless, synaptic density and spatial learning were improved in transgenic mice with pioglitazone treatment, in association with the increased plaque fibrillarity. These translational data suggest that a shift toward higher plaque fibrillarity protects cognitive function and brain integrity. Increases in the Aβ-PET signal upon immunomodulatory treatments targeting Aβ aggregation can thus be protective

The macroscopic intestinal anatomy of a lowland tapir (Tapirus terrestris)

Tapirs are the only group among the perissodactyls for which no recent description of the gastrointestinal tract (GIT) exists. Historical depictions of the GIT of tapirs suggest a similarity to the GIT of equids, but do not resolve the question whether the isthmus at the caeco-colical junction, and at the transition from the proximal colon to the colon transversum—both evident in horses—occur in tapirs as well. Here, we describe the macroscopic anatomy of the GIT of a captive, adult lowland tapir (Tapirus terrestris). While similar to equids in terms of the overall design and, in particular, the two mentioned isthmuses, the proximal colon of the tapir appeared less pronounced than in other perissodactyls, resulting in a GIT in which the caecum appeared as the most voluminous fermentation chamber. This finding is supported by the particular location of the ileo-caecal junction, which does not visibly separate the caecum from the colon, or the caecum head from the caecum body, but enters the caecum body in its upper third

The macroscopic intestinal anatomy of a lowland tapir ( Tapirus terrestris )

Tapirs are the only group among the perissodactyls for which no recent description of the gastrointestinal tract (GIT) exists. Historical depictions of the GIT of tapirs suggest a similarity to the GIT of equids, but do not resolve the question whether the isthmus at the caeco-colical junction, and at the transition from the proximal colon to the colon transversum—both evident in horses—occur in tapirs as well. Here, we describe the macroscopic anatomy of the GIT of a captive, adult lowland tapir (Tapirus terrestris). While similar to equids in terms of the overall design and, in particular, the two mentioned isthmuses, the proximal colon of the tapir appeared less pronounced than in other perissodactyls, resulting in a GIT in which the caecum appeared as the most voluminous fermentation chamber. This finding is supported by the particular location of the ileo-caecal junction, which does not visibly separate the caecum from the colon, or the caecum head from the caecum body, but enters the caecum body in its upper third