Fig. 3

Aβ-triggered inflammatory signals detected by in vivo PET with ¹¹C-PBR-28. a Whole-brain time activity curves in control versus obese mice 2 months post-treatment. Obesity significantly reduced brain ¹¹C-PBR-28 uptake, most likely reflecting altered whole body ¹¹C-PBR-28 distribution. b Group comparison of ¹¹C-PBR-28 accumulation at the infusion site at 2 and 3 months post-treatment (relative to individual baseline accumulation). Obesity combined with Aβ infusion synergistically increased radioligand accumulation at the infusion site, peaking at 2 months, but persisting at 3 months. c Time activity curves at the infusion site of vehicle versus Aβ-infused mice control mice at 2 months. d Time activity curves at the infusion site in vehicle versus Aβ-infused obese mice at 2 months. e Sagittal and coronal PET images in control and obese mice infused with vehicle or Aβ at 2 (T2) and 3 months post-treatment (T3). A marked increase in radioactivity was observed surrounding the Aβ infusion site in the lateral ventricle (indicated by dashed red outline) extending into the dorsal hippocampus (indicated by white dashed outline). Images were generated by summation of dynamic data between 40 and 60 min after injection of ¹¹C-PBR-28 and were overlaid on the MRI template. *p < 0.05