Nuclear and cytoplasmic expressions of the receptor for advanced glycation end products (RAGE) in the rat central nervous system.

Abstract

The receptor for advanced glycation end products (RAGE) is a transmembrane protein involved in the induction of inflammatory processes and oxidative stress after interacting with its ligands on the cell surface. Lo-calization on the cell surface is necessary for interaction with the ligands. This study aimed to determine the expression of RAGE in different parts of the nor-mal rat brain and cerebellum using the immunofluorescence technique. Sev-eralcerebral cortex layers (molecular/granular layers: M/GL; pyramidal layer: PL) and the hypothalamus were analyzed, as well as the molecular layer (CML) and the granular layer (CGL) of the cerebellum. Cells with RAGE-positive nu-clei were generally observed in the brain’s cerebral cortex and cerebellum. In the M/GL, cells with different degrees of positivity in the nucleus and cyto-plasm accompanied by RAGE-positive material in the adjacent extracellular space were observed, and RAGE-positive material in the neuropile. Pyramidal neurons presenting various degrees of nuclear RAGE-positive material budding and cells with different degrees of nuclear and cytoplasmic positivity were ob-served in PL. The hypothalamus showed a high number of cells with RAGE-positive granules adjacent to the nucleus and in the cytoplasm; nuclei remained negative. Many positive nuclei were observed in CML; they were scarce in CGL. These data suggest the storage of RAGE at the nuclear and cytoplasmic levels in healthy rats and hypothesize the possible translocation of this molecule to the cell surface in pathological conditions.