Fig. 4.

CNS inflammation is more sporadic with age in long-term clasping PPARα^mut/WT 2D2⁺ mice. PPARα^mut/WT 2D2⁺ females and sex-matched PPARα^mut/WT 2D2⁻ littermates (n = 5 mice per group) from the study in Fig. 3 were transcardially perfused with gadolinium and PFA fixative at 9 mo of age. Fixed spinal cord and brain specimens were then harvested for MR imaging within bone and then were decalcified, embedded in paraffin, and sectioned for histological analysis of inflammation. (A and B) Area of hyperintensity (designated by a white arrow) on a T2-weighted image of the spinal cord in 1 PPARα^mut/WT 2D2⁺ mouse in cross-section (A) or longitudinal (B) views. (C) The same structure in paraffin sections prepared from the imaged cord stained with LFB/H&E. (D–F) One focus of inflammation corresponded to an area of hyperintensity in another PPARα^mut/WT 2D2⁺ mouse stained with anti-CD3 (D), anti-IBA1 (E), or LFB/H&E (F). (G–I) Example of submeningeal inflammation in the spinal cord (G) and small perivascular cuffs in the cerebellum (H) or cerebral peduncle (I) in another PPARα^mut/WT 2D2⁺ mouse of similar age that had not been imaged by MR. (Scale bar, 100 µm.)