Rosiglitazone, an agonist of peroxisome proliferator-activated receptor γ, decreases immunoreactivity of markers for cell proliferation and neuronal differentiation in the mouse hippocampus

In the present study, we investigated the regulating effects of rosiglitazone (RSG), a synthetic agonist of peroxisome proliferator-activated receptor γ, treatment for 28 days on the cell proliferation and neuronal differentiation in the mouse hippocampal dentate gyrus by 5-bromo-2′-deoxyuridine (BrdU), Ki67 and doublecortin (DCX) immunohistochemistry. These markers were detected in the subgranular zone (SGZ) of the dentate gyrus in vehicle- and RSG-treated groups. In the RSG-treated group, the number of BrdU-, Ki67- and DCX-immunoreactive cells was significantly decreased compared to those in the vehicle-treated group. In addition, brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor levels were significantly decreased in the dentate gyrus of the RSG-treated groups compared to the vehicle-treated group. These results indicate that RSG treatment decreases immunoreactivities of markers for cell proliferation and neuronal differentiation and levels of neurotrophic factors in the SGZ of the hippocampal dentate gyrus.